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In 1926, Haldane, in "The Origin of Life," wrote that "the cell consists of numerous half-living chemical molecules suspended in water and enclosed in an oily film.  When the whole sea was a vast chemical laboratory the conditions for the formation of such films must have been relatively favorable" (Haldane 1926:3).  [added 02/01/03]
In 1926, James Batcheller Sumner crystallized urease (Sumner 1926).
In 1926, Sturtevant found the first gene inversion in Drosophila.
In 1926, Warburg discovered a carbon monoxide-sensitive iron porphyrIn enzyme which catalyses cell respiration.
In 1926, Volterra published his deduction of the nonlinear differential equation which describes the fluctuating balance of prey/predator populations: If prey increase, predators will also until prey decrease. As the predators starve, the prey increase. The two populations fluctuate out of phase with each other due to the length of the gestation period delaying the population peaks; i.e., the predator population is still growing after the prey population has begun to decline. This equation is similar to Lotka's logistic growth equation, although based on classical mechanics and W. R. Hamilton's principle of least growth. It is sometimes called the Lotka-Volterra equation.
In 1926, Dirac solved the derivation of Planck's law and called Heisenberg's quantity symbols q-numbers and ordinary numbers c-numbers (Dirac 1926:561-569).
In 1926, Erwin Rudolf Josef Alexander Schrödinger initiated the development of the final quantum theory by describing wave mechanics, which predicted the positions of the electrons, vibrating as Bohr's standing waves. The mathematics itself is the deterministic 'classical' mathematics of classical waves. It in no way acknowledges the actual phenomena, a minute flash which propagates the wave, or indeterminism, which enters when the intensity of the mathematically the dual wave-particle nature of such things as electrons through their wave function, or eigenfunction, involving the coordinates of a particle in space, e.g., y(x,y,z). This 'wave mechanics' predicted the positions of the electrons, vibrating as Bohr's standing waves. It in no way acknowledges the actual phenomena, a minute flash which propagates the wave, or indeterminism, which enters when the intensity of the wave is related to the probable location of the flash. While the mathematics itself is the deterministic 'classical' mathematics of classical waves, the results show complete mathematical equivalence to matrix mechanics.
Later in 1926, Born, in "Quantenmechanik der Stossvorgînge," considering that the wave does not describe the exact behavior of any particle, interpreted the equation in terms of Bohr-Kramers-Slater probability. This added the arrow of time to Schrödinger's classical, i.e., 'reversible,' mathematics, and 'quantum mechanics' was completed (Born 1926:52-55).
Still later in 1926, Heisenberg, in "Über die Spektra von Atomsystemen mit zwei Elektronen," using the unified quantum mechanics, quickly calculated the spectrum of several states of the helium atom.
In 1926, de Broglie attempted to obviate the quantum mechanical conundrum 'wave or particle' by maintaining instead that it is 'wave and particle,' reasoning that "quantum phenomena do not exclude a uniform description of the micro and macro worlds..., system and apparatus" (Bell 1987:175). Waves may have a corpuscular aspect and particles may have a wave aspect, depending on the properties of the model to be explained. For example, photon particles can be described as concentrated packets of waves, called 'wave packets,' with zero mass energy and electric charge and without well-defined edges.
In 1926, Oskar Klein, attempting to explain what happened to Kaluza's fifth dimension, proposed that we do not notice it because it is "'rolled up' to a very small size [and that] what we normally think of as a point in three-dimensional space is in reality a tiny circle going round the fourth dimension" (Davies and Brown 1988:49). He also suggested that "the origin of Planck's quantum may be sought just in this periodicity in the fifth dimension" (Klein 1926:516).
In 1926, Klein and, independently, Walter Gordon developed an equation in relativistic quantum mechanics for spin-zero particles.
In 1926, Gregor Wentzel, Kramers, and Leon Brillouin, each independently, invented the 'semiclassical, or WKB, approximation,' a technique in quantum mechanics, wherein "the wave function is written as an asymptomatic series with ascending powers of the Planck constant h, with the first term being purely classical" (Dictionary of Physics 2000:444).
In 1926, Robert Alexander Watson-Watt proposed the name 'ionosphere' for the conducting atmospheric layer.
In 1926, Eddington, in The Internal Constitution of the Stars, a summary of his work, said that all stars must maintain a temperature of at least forty million degrees in order to maintain their fuel supply.
In 1926, Ralph Howard Fowler, in "On Dense Stars," using the statistical description of atoms published the previous year by Fermi, showed the correct relation of energy and temperature in a white dwarf, leading to the conclusion that they "do not shine by thermonuclear reactions and that their light must come from the slow leakage of heat contained in the nondegenerate nuclei" (Lang and Gingerich 1979:573).
In 1926, Donald Howard Menzel, in "The Planetary Nebulae," raised the possibility that the Balmer emission lines, lines in the hydrogen spectrum created when electrons drop back to a lower energy level, are "the result of photoionization by ultraviolet star light, followed by recombination of free electrons and protons" (Lang and Gingerich 1979:573).
In 1926, Gregory Breit and Merle Tuve measured the distance to the ionosphere by measuring the time needed for a radio signal to bounce back.
In 1926, [?] Busch focused a beam of electrons with a magnetic lens, laying the foundations of electron optics.
In 1926, Lorentz modelled the damming of the Zuiderzee as the head of a Dutch government committee (Cercignani 1998:202). [added 02/01/03]
In 1926, Jan-Christian Smuts coined 'holism in order to give a name to "the view that an intergrated or organic whole has a reality independent of and greater than the sum of its parts" (Webster's 1979:867).
In 1927, Muller demonstrated that the X-irradiation of sex cells in Drosophila causes an increased number of mutations, enabling mutations to be created experimentally.
In 1927, Landsteiner discovered the M and N blood groups.
In 1927, Martin Heidegger published Sein und Zeit, an original analysis of human existence. Unnoticed at the time in psychiatric circles, it later became the basis for 'existential analysis.'
In 1927, Heisenberg, in "Über den anschaulichen Inhalt der quantentheoretischen Kinematik und Mechanik," said electrons do not possess both a well-defined position and a well-defined momentum, simultaneously; i.e., "Even in principle we cannot know the present in all detail" (Heisenberg 1927:83). This uncertainty has nothing to do with the limitations of human observers; it is intrinsic, and converts absolute certainties into relative probabilities. Expressed as an inequality, one may say that the smaller the uncertainty about position, the greater the uncertainty about momentum, and vice-versa. "Quantum uncertainty makes it impossible to define any set of conditions precisely for the atoms" (Gribben 1998:19), and thus refutes, in principle, any possibility of, say, a gas in a box reversing itself to its original position over any amount of time, in the manner of Poincaré's ideal 'cycle times.' Quantum uncertainty also provides the loophole to the law of the conservation of energy through which the forces embodied in photons make their brief appearances. Born and Pasqual Jordan collaborated with Heisenberg setting up the matrix algebra to describe this 'uncertainty principle.'
In 1927, Bohr, after discussions with Heisenberg, took the position, which came to be known as the Copenhagen interpretation, that the impossibility of simultaneously measuring a particle's position and its momentum, the 'complementarity principle' as he called it, is engendered by the measurement process in a specific experimental situation; i.e., measurement is inseparable from wave function reduction, or 'collapse.' "Wave-packet the only irreversible feature of quantum mechanics and the one extraneous to the basic equations of this theory, which are perfectly time-reversible" (Cercignani 1998:118).  Measurement is also a means of communication, and communication requires a common time.  "Every atomic phenomena is closed in the sense that its observation is based on a recording...with irreversible functions" (Bohr, quoted in Prigogine 1996:156).  The complementary principle itself implies closure: The microworld "part has no meaning except in relation to the [macroworld] whole, the total context....  What Bohr's philosophy suggests is that words like electron, photon, or atom should be regarded [like energy as a useful model that consolidates] in our imagination what is actually only a set of mathematical relations connecting observations" (Davies and Brown 1986:12,26).  
In 1927, Born and Julius Robert Oppenheimer devised an adiabatic approximation in which "the motion of atomic nuclei is taken to be so much slower than the motion of the electrons that, when calculating the motions of electrons, the nuclei can be taken to be fixed positions" (Dictionary of Physics 2000:47). An adiabatic approximation occurs when the time dependence of parameters are slowly varying.
In 1927, George Paget Thomson diffracted electrons by passing them In a vacuum through a thin foil, thus verifying de Broglie's wave hypothesis.
In 1927, Clinton Joseph Davisson and Lester Halbert Germer measured the length of a de Broglie wave by observing the diffraction of electrons by single crystals of nickel.
In 1927, Paul Ehrenfest proved the theorem that "the motion of a wave packet is in accord with the motion of the corresponding classical particle, if the potential energy change across the dimensions of the packet is very small" (Dictionary of Physics 2000:529).
In 1927, Walter Heitler and Fritz London showed that chemical bonding, the force which holds atoms together, is electrical and a consequence of quantum mechanics.
In 1927, Dirac described a method of quantizing the electromagnetic field (Dirac 1927:243-265, 710-728).
In 1927, Einstein and Leo Szilard applied for a patent on a pump for liquid metals using a magnetic field to induce a ponderomotive force on a closed current loop in the fluid conductor. These pumps are used to circulate liquid sodium coolant in nuclear reactors.
In 1927, Georges Lemaître proposed, independently of Friedman, an expanding model of the universe from an initial singularity and consistent with Einstein's General Theory. The main difference from Friedman was that Lemaître included both the redshift-distance relation and radiation pressure. This enabled him to show the importance of the early stages of the expansion: When the "primeval atom" exploded outwards, "the expansion [had] been set up by the radiation itself," and "the receding velocities of extragalactic nebulae are a cosmical effect of the expansion of the universe" (Lemaître 1931:490). One important implication is that the universe is not infinite, which incidently explains away Olbers' paradox.
In 1927, Jan H. Oort, confirming Lindblad's hypothesis that the Milky Way is rotating, concluded the "stars closer to the galaxy's nucleus will generally revolve faster than the Sun, and hence those inner stars in the direction of the Sun's motion will be pulling away from the Sun, whereas those inner stars symmetrically opposite the direction to the nucleus will be catching up" (Lang and Gingerich 1979:555).
In 1927, Menzel obtained accurate measurements of the surface temperatures of Mars and Mercury.
In 1927, Vannevar Bush started construction on the 'Differential Analyzer,' an analog computer, which measured the rotation of various rods by mechanical means, in order to speed the solution of problems related to the electric power network.
In 1927, Richard Buckminster Fuller began the exploration of geodesics, "the most economical relationship between two events" (Fuller 1975:373), such as spherical great circles. This led to the development of geodesic domes, in the early 1940s, and the dymaxion map, patented In 1946.
In 1928, Albert Szent-Györgi showed that hexuronic acid was vitamIn C and proposed the name L-ascorbic acid.
In 1928, Heinrich Otto Wieland and Adolf Otto Reinhold Windaus determined the structure of the cholesterol molecule.
In 1928, Lewis Stadler induced mutations in maize using ultraviolet light.
In 1928, Alexander Fleming discovered penicillin, a relatively innocuous antibiotic because it interfered with the synthesis of cells walls, a process specific to bacteria, rather than with metabolism.
In 1928, Frederick Griffith discovered that live pneumococci could acquire genetic traits from other, dead pneumococci (Griffith 1928).
In 1928, Linus Carl Pauling, in "The Shared Electron Chemical Bond," wrote that "in the case of two hydrogen atoms in the normal state brought near each other, the eigenfunction...corresponds to a potential [that] causes the two atoms to combine to form a molecule. This potential [involves] an interchange of position of the two electrons forming the bond, so that each electron is partially associated with one nucleus and partially with the other. [This] leads to the result that the number of shared bonds possible for an atom of the first row is not greater than four, and for hydrogen not greater than one" (Pauling 1928:359-360). An eigenfunction is a function of an operator which yields a state that when acted on by that operator yields the same state multiplied by a number.
In 1928, George Gamow explained the lifetimes of alpha radiation using the Schrödinger equation. Alpha decay is a 'tunnelling process.' The tunnelling effect involves the waviness of an alpha particle, or any electron, which makes it finitely probable it will tunnel through what would have been an insurmountable obstacle if it were a classical particle. Having tunnelled, the alpha particle is no longer held by the 'strong nuclear force' and is repelled or radiated away. Gamow also pointed out that the edges of wave packets can interact over distances at which particles would be repelled, making nuclear fusion possible at temperatures that exist inside the Sun and other stars.
In 1928, Gamow devised the 'liquid drop model' of the atomic nucleus, implying that it is held together by something like surface tension.  "The success of the model has been associated with the fact that the binding forces in both the nucleus and the liquid drop are essentially short-ranged" (Issacs 2000:271).
In 1928, Rolf Wideröe and, independently, Szilard invented linear accelerators of a more advanced design than the one G. Ising had proposed. In his patent application, Szilard said, "The electric field can be conceived of as a combination of an electric field in accelerated motion from left to right and an electric field of decelerated motion from right to left. The device is operated in such a way that the velocity of the accelerated ion equals, at each point, the local velocity of the field moving from left to right" (Szilard, quoted in Telegdi 2000:26).
In 1928, Chandrasekhara Raman observed weak, inelastic scattering of light from liquids. This effect, known as 'Raman scattering,' arises from vibrating molecules.
In 1928, Albrecht Unsöld, using a spectroscope, investigated light from the Sun and "interpreted the strength of the hydrogen lines an implying that there are roughly a million times as many hydrogen atoms as anything else" (Gribbin and Gribbin 2000:94).
In 1928, Weyl, in Gruppentheorie und Quantenmechanik, created a matrix theory of continuous groups and discovered many of the regularities of quantum phenomena could best be understood by means of group theory (Weyl 1928).
In 1928, John von Neumann conceived 'game theory.'
In 1928, London revived Weyl's work on symmetry but showed that local gauge symmetry applies not to space but to the electromagnetic field which enforces the conservation of electric charge between local areas.
In the late 1920s, it was found that deoxyribonucleic acid (DNA) was located exclusively in the chromosomes, whereas ribonucleic acid (RNA) was located mainly outside the nucleus.
In 1929, Haldane showed that the development of organic compounds took place before the first living things. He also pointed out that ultraviolet radiation could have been the spark which animated the "hot, dilute soup" (Haldane 1933:149).
As early as 1929, Frank MacFarland Burnet came to believe that "resistant [to viruses] bacterial variants are produced by mutation in the culture prior to the addition of virus [and that] the virus merely brings the variants into prominence by eliminating all sensitive bacteria" (Luria and Delbrück 1943:491-492). "Where the mutational change to resistence is correlated to a change of phase, from smooth to rough or vice-versa, the change of the [antigenic make-up of the cellular] surface must be a direct result of the mutation" (Luria and Delbrück 1943:510; Burnet 1930).
In 1929, Fisher, in The Genetical Theory of Natural Selection, provided a mathematical analysis of how the distribution of genes In a population will change as a result of natural selection, and maintained that once a species' fitness is at a maximum, any mutation will lower it.
In 1929, David Keilin, having discovered 'cytochromes,' proteins that function as electron-carriers, four years earlier, formulated the "fundamental idea of aerobic energy systems: the concept of the respiratory chain" (Mitchell 1978; Keilin 1929). [added 02/01/03]
In 1929, K. Lohmann, Cyrus Hartwell Fiske, and Y. Subbarow, in muscle extracts, isolated 'adenosine triphosphate' (ATP), the phosphate bonds of which, when hydrolysed, release energy, and 'phosphocreatine,' from which some of the phosphorus in ATP in obtained.
In 1929, Adolf Friedrich Johann Butenandt and, independently, Edward Adelbert Doisy isolated 'estrone,' a sex hormone, from urine.
In 1929, Jung, in a commentary on Das Geheimnis der goldenen Blüte, translated as The Secret of the Golden Flower, began an exploration of the significance of alchemical symbolism in depth psychology for the resolution of conflicts of opposites. Over the following 25 years, he expanded the study of mandorlas, noticing analogies between quadripartite schemes, e.g., father-son-spirit-mother, black-green-red-gold, etc., and taking them to be archetypal ideas.
In 1929, Robert Jemison van de Graaf developed an electrostatic particle accelerator.
In 1929, Szilard, in "Über die Entropieverminderung in einem thermodynamischen System bei Eingriffen intelligenter Wesen, "disputed Maxwell, showing that 'inspection,' or information, is inevitably associated with a decrease in entropy; that is, the energy gained by the discriminations of the Demon will be wholly offset by the energy spent in acquiring the information on which the discriminations are based (Szilard 1929:539-541).
In 1929, Dirac published his 'relativistic wave equation' which describes the electron's spin and led to the prediction of the electron's antiparticle, the 'positron.'. This more or less completed quantum field theory which combined quantum mechanics with Einstein's special relativity: "Just as photons were particles--the quanta--associated with the electromagnetic field, so the electron was associated with an electron field and the proton with a proton field. Every kind of particle was intimately intertwined with a field, and every kind of field with a particle. Since there were gravitational fields, [the prediction was made that] there must be particles called gravitons.... In the picture provided by quantum field theory, the particles influence each other by bouncing photons back and forth" (Johnson 1999:61-62).
In 1929, Nevill F. Mott, in "The Wave Mechanics of a-Ray Tracks," analyzed the "wave functions [of the tracks] in the multispace formed by the co-ordinates both of the a-particle and of every atom" on a photographic plate in a cloud chamber..., [with the nuclei] considered effectively at rest" (Mott 1929:79-80), that is, stationary. The equation he used is similar to Born's first probability equation which is time-independent.
In 1929, Hubble, in "A Relation between Distance and Radial Velocity among Extra-Galactic Nebulae," observed that all galaxies are moving away from each other. Correlating the distance of a particular galaxy and the speed with which it is receding by an analysis of the light spectra, he noted a persistent cosmological redshift, and explained this in terms of the Doppler effect: The light is receding and the farther away the larger the 'gravitational redshift.'  It is the product of the stretching of the color wavelength by gravity; i.e., when an object has a very strong gravitational pull, what starts out relatively short wave (blue) will become relatively long wave (red).  
In 1929, Robert d'Escourt Atkinson and Franz Houtermans, inspired by Gamow's work, published calculations of how the tunnel effect might operate in stars and showed that even with the tunnel effect only the fastest-moving particles with the smallest positive charge, i.e., protons from hydrogen nuclei, could penetrate the barriers. Their conclusion, and Unsöld's and Menzel's, regarding the preponderance of hydrogen on the Sun was ignored by most astronomers who preferred to believe that heavy elements prepondered, as on the Earth.
In 1929, Frank Whittle, combining the concepts of rocket propulsion and gas turbines, invented jet propulsion. Independently, Hans von Ohain put together the same combination in 1933.
In 1930, Friedrich Breinl and Felix Haurowitz published a proposal for a template theory of antibody production (Breinl and Haurowitz 1930).
In 1930, Gavin de Beer formalized the morphological modes in which ontogenetic acceleration and retardation could produce evolution.
In 1930, Fisher discussed stable, or equilibrium, states of the sex ratio in terms which later came to be called game theory. Taking random fluctuation of allelic populations into account and treating the processes of gene frequency as stochastic processes, he concluded that chance effects were negligible.
By 1930, Phoebus Aaron Levene had "elucidated the structure of mononucleotides and [shown them to be] the building blocks of nucleic acids. He also isolated the carbohydrate portion of nucleic acids and distinquished deoxyribose from ribose" (German Life Science Information Service 1993:14; Levene and Bass 1931).
In 1930, Léon Rosenfeld, in "Zur Quantelung der Wellenfelder," applied quantum field theory to the gravitational field and was able to compute the gravitational self-energy of a photon, but obtained a quadratically divergent result.
In 1930, Dirac, in the first edition of his textbook The Principles of Quantum Mechanics, defined the 'superposition' of states by saying that a "state A may be formed by the superposition of states B and C when, if any observation is made on the system In state A leading to any result, there is a finite probability for the same result being obtained when the same observation is made on the system in one (at least) of the two states B and C. The Principle of Superposition says that when any two states B and C may be superposed in accordance with this definition to form a state A and indeed an infinite number of different states A may be formed by superposing B and C in different ways" (Dirac 1930:15-16). Dirac went on to say that this principle forms the foundation of quantum mechanics, and is completely opposed to classical mechanics since this principle requires indeterminacy in the results of observations. On the other hand, superposition is thought to only occur at the unobservable microscopic level; it theoretically could but "does not happen in the world we know," the macroscopic world (Park 1990:426).
In 1930, Ernest Orlando Lawrence published the principle of the cyclotron which is using a magnetic field to curl up the particle trajectory of a linear accelerator into into a spiral. This permitted acceleration of atoms to high speeds and the creation of nuclear reactions.  
In 1930, Subrahmanyan Chandrasekhar calculated that "white dwarfs more massive than 1.4 suns would collapse under their own weight, paving the way for the theoretical prediction of neutron stars and black-holes" (Begelman and Rees 1996:30).
In 1930, Menzel, using Stoney's argument, inferred the presence of hydrogen on the giant planets.
In the early 1930s, the Theoretical Biology Club, at Cambridge University, adopted the process philosophy of Whitehead, in which the metaphysics of static substances is replaced by an ontology in which 'things' are actually emerging processes (Depew and Weber 1995:416). John Desmond Bernal, Joseph Needham, and Conrad Hal Waddington were members.
Beginning in the 1930s, K. Lorenz, Nikos Tinbergen, and Irenäus Eibl-Eibesfeldt investigated natural, as opposed to contrived, animal behavior, and were able, by using comparative analysis of closely related species, to discern stereotyped natural behavior structures or episodes (thus making the notion of 'instinct' respectable). This study of innate and learned responses and the interaction between them is called ethology.
In the 1930s, Rupert Wildt, building on Very's suggestion that Venus's atmosphere is mainly carbon dioxide, proposed that since that is highly opaque to surface radiation a considerable greenhouse effect would be produced.
In 1931, Harriet B. Creighton and Barbara McClintock, working with maize, and Curt Stern, working with Drosophila, provided the first visual confirmation of genetic 'crossing-over.' (Creighton and McClintock 1931).
In 1931, Sewall Wright concluded that 'random drift,' or chance fluctuation of allelic populations, was a significant factor in evolution. This opposed Fisher's opinion. (It should be noted that at this period the assumptions necessary in order to quantify genes resulted in much over-simplification).
In 1931, Ulf Svante von Euler isolated the peptide 'substance P.'
In 1931, Pauling published The Nature of the Chemical Bond and the Structure of Molecules and Crystals, detailing the rules of covalent bonding.
IIn 1931, John Howard Northrop and Moses Kunitz, applying the phase rule solubility test for the homogeneity of dissolved solids, corroborated J. B. Sumner's belief that enzymes are proteins. [added 02/01/03]
In 1931, Ernst August Friedrich Ruska and colleagues invented the prototype of the transmission electron microscope. [added 02/01/03]
In 1931, Hans Albrecht Bethe provided a solution to the one-dimensional Ising model on which most subsequent solutions to the two-dimensional model depend.
In 1931, Pauli, in order to solve the question of where the energy went in beta decay, predicted the existence of a 'little neutral thing,' the 'neutrino.'  
In 1931, Kurt Gödel published his proof that the axiomatic method has inherent limitations, namely, because the consistency of a set of axioms cannot be derived from itself, it is incomplete, thus showing that the aims of Frege , Hilbert, and B. Russell could never have been achieved.
In 1931, Herbert Butterfield characterized the 'Whig interpretation of history' as "the tendency in many historians to write on the side of the Protestants and Whigs, to praise revolutions provided they have been successful, to emphasize certain principles of progress In the past and to produce a story which is the ratification if not the glorification of the the present" (Butterfield 1931:v).
In 1931, Atkinson suggested that "the abundance of elements [in stars] might be explained by the synthesis of heavy nuclei from hydrogen and helium by successive proton captures, [which protons] would be absorbed by nuclei until they become unstable and ejected alpha particles" (Lang and Gingerich 1979:303).
In 1931, Bernhard V. Schmidt invented a new type of telescopic optical system which made possible sharp photographs of wide areas of the sky.
In 1932, Haldane introduced the term 'altruist.'
In 1932, A. Bethe conceptualized 'pheromones,' chemicals secreted by animals and insects for communication.
In 1932, Hans Adolf Krebs and Kurt Henseleit discovered the 'urea cycle,' a circular pathway in liver cells in which excess ammonia, produced by the breakdown of amino acids, and carbon dioxide react together creating urea, which is filtered by the kidneys and excreted. [added 02/01/03]
In 1932, Axel Hugo Teodor Theorell isolated myoglobin and therefore was able to show its oxygen absorption and carrying capacities. [added 02/01/03]
In 1932, Franz Moewus initiated studies on sexuality in a flagellated protozoa, the green algae Chlamydomonas, and subsequently demonstrated that unicellular organisms possessed genes that behave in the classical Mendelian way.
In 1932, Walter Cannon, in The Wisdom of the Body, maintained that the body's steady state is regulated by negative feedback mediated by the autonomic nervous system through the sympathetic and parasympathetic divisions of the hypothalamus.
In 1932, Frits Zernike invented the phase-contrast telescope (Zernike 1934). By 1935, he was applying the same principles to microscopes, but was unable to get them produced commercially until 1941. This development allowed unstained living cells to to be seen in detail for the first time. [added 02/01/03]
Early in 1932, Irène Curie and Frédéric Joliot bombarded nonradioactive beryllium with alpha particles, transmuting it briefly into a radioactive element.  
In 1932, James Chadwick described the helium alpha particles which created the Curie-Joliet effect as consisting of two protons and two neutrons, thus isolating the neutron, the first particle discovered with zero electrical charge. It has almost the same mass as a proton. Atoms with identical chemical properties but different numbers of neutrons, and thus different masses, are called isotopes.
In 1932, Harold Clayton Urey along with his teacher G. N. Lewis and colleagues demonstrated the existence of deuterium, or heavy hydrogen, spectroscopically.  Subsequently, he isolated isotopes of heavy oxygen, nitrogen, carbon, and sulphur.  
In 1932, Fermi succeeded in intensifying the Curie-Joliet effect by using the newly discovered and very massive neutrons in beta rays instead of alpha rays.
In 1932, Carl David Anderson, using a cloud chamber in the study of cosmic rays, discovered the positron, or positive electron, fulfilling Dirac's prediction.  
In 1932, Heisenberg proposed a model of the atom in which protons and neutrons exchange electrons to achieve stability.
In 1932, John Douglas Cockcroft and Ernest T. S. Walton built the first linear accelerator with which they bombarded lithium with protons, producing helium and achieving the first artificial nuclear reaction.
In 1932, Peter Joseph Wilhelm Debye and others independently observed the diffraction of light by ultrasonic waves.
In 1932, von Neumann, in Mathematische Grundlagen der Quanten Mechanik, dealt with the dualistic paradox by emphasizing the role of the observer, saying that it is we, and our consciousness, who produce the collapse of the wave function, not 'hidden variables.'
[The dualistic paradox may be thought of on analogy to the field anthropologist's problem: After meeting the anthropologist, 'primitive' people are changed by the encounter; or, as Bohr thought, analogous to the partition between subject and object, the movability of which enables us to talk about ourselves (Petersen 1968:3-4). However, in practice the distinction between wave and particle, between classical and quantum, makes very little difference to the experimenter. The distinction is made for a particular application depending on how much accuracy or completeness is desired. "It is the toleration of such an ambiguity, not merely provisionally but permanently, and at the most fundamental level, that is the real break with the classical ideal.... Indeed good taste and discretion, born of experience, allow us largely to forget, in most calculations, the instruments of observation" (Bell 1987:188-189)].
In 1932, Einstein and de Sitter put forth a revised cosmological model, which was a solution to the Friedman equations, took account of Hubble's proof of the expansion of the Universe, and tentatively implied an initial singularity.
In 1932, Shapley published the first edition of the Shapley-Ames Catalogue of galaxies.
In 1932, Edward H. Land invented polarizing film.
In 1932, George Kingsley Zipf published the scaling relationships which are now known as Zipf's law, namely, that ordered quantities are apt to be inversely proportional to their rank, that is, proportional to 1, 1/2, 1/3, 1/4, etc.
In 1933, Goldschmidt concluded that evolution was the result of sudden changes by successful mutations that act on early embryological processes (Goldschmidt 1933) .
In 1933, John Howard Northrop isolated and crystallized the protein-splitting enzymes pepsin, trypsin, and chymotrypsin (Northrop 1935). [revised 02/01/03]
In 1933, M. Goldblatt and von Euler discovered 'prostaglandins.'
In 1933, Theorell isolated the 'yellow enzyme,' separated it into a catalytic coenzyme and apoenzyme, and found the main ingredient to be albumin. This led to Theorell's discovery of the chemical chain reaction known as 'cellular respiration' in which food is translated into energy. [added 02/01/03]
In 1933, I. Curie and Joliet, using polonium plus beryllium In a cloud chamber, proved that "hard gamma rays...produce electron-positron pairs by materialization....  They also noted single positrons in addition to pairs" (Segrè 1976:193).  
In 1933, Fermi developed a theory of decay and weak interactions in which a neutron changed into a proton, emitting a neutron and a neutrino.  The following year, Heisenberg and others extended it in terms of the strong nuclear force.  
In 1933, Karl Jansky, in the course of investigating atmospheric static which was interfering with radio communications, established that the radio source he had been hearing since the previous year came from outside the solar system.
In 1933, Fritz Zwicky discerned that a "considerable fraction of the mass had been missed" in measuring the velocities of certain galaxies (Peebles 1993:419). What was first known as 'missing mass' became known as 'dark matter,' and today is discerned mainly through its gravitational effects. "The nature of this dark matter is unknown.... Exotic [i.e., undetected] particles such as axions, massive neutrinos or other weakly interacting massive particles (collectively known as WIMPs) have been proposed.... A less exotic alternative is normal matter in the form of bodies with masses ranging from that of a large planet to a few solar masses. Such objects, known collectively as massive compact halo objects (MACHOs), might be brown dwarfs...(bodies too small to produce their own energy through fusion), neutron stars, old white dwarfs or black holes" (Alcock et al. 1993:621).
In 1934, Bernal and Dorethy Crowfoot began the structural analysis of proteins (Bernal and Crowfoot 1934) and, later, William Thomas Astbury established that the orderliness of cells was a structural, or crystalline, orderliness. This conception was revolutionary, marking the disappearance of the 'colloidal' conception of vital organization, itself a sophisticated variant of the older doctrine of 'protoplasm.'
In 1934, Warburg discovered the coenzyme nicotinamide and, the following year, that it is a constituent of cells.
In 1934, Butenandt and colleagues isolated the hormone progesterone. [added 02/01/03]
In 1934, U.v. Euler discovered a fatty acid which he called 'prostaglandin,' in the mistaken belief that it was produced by the prostate gland. [added 02/01/03]
In 1934, Henrik Dam , working with baby chickens, isolated and identified a hemorrhagic factor which he called Koagulations Vitamine, or vitamin K. Two years later, Doisy synthesized it. [revised 02/01/03]
In 1934, de Beer and Julian Sorell Huxley published The Elements of Experimental Embryology in which the central concept is that of a dominant region in relation to which other regions are specified.
In 1934, Pavel Alekseyevich Cherenkov discovered that when high-energy charged gamma ray particles pass through a transparent medium at a speed greater than the speed of light in that medium they emit light at certain angles. This is known as Cherenkov (sometimes Cerenkov) radiation.
In 1934, Szilard filed the first patent application for the idea of a neutron chain reaction. The following year, in order to keep the patent a secret, he assigned it to the British Admiralty.
In 1934, I. Curie and Joliot announced the discovery of "artificial radiation obtained by bombarding certain nuclei with alpha particles" (Segrè 1976:198).  
In 1934, Fermi, Edoardo Amaldi, Bruno Pontecorvo, Franco Racetti, and Emilio Segrè, while improving on the Curie-Joliet artificial radiation technique by using neutrons to bombard uranium, established that "slow neutrons [having passed through paraffin] were much more efficient than fast ones in producing certain nuclear reactions" (Segrè 1976:205; Fermi et al 1934).  In other words, they showed how nuclear reactions could be controlled.  
In 1934, I. Noddack expressed scepticism at Fermi's transuranic elements, insisting that "it was necessary to compare the chemistry with the chemistry of all the known elements because it would be conceivable that the nucleus could break into several large fragments" (Malley 2000:947).  In other words, she questioned whether the transformed uranium was not heavier, as Fermi supposed, but in fact lighter.  At the time nobody else realized that this was possible and Noddack did not do the experiment which would have proved that her conjecture was correct.  
In the five years subsequent to 1934, Glenn Seaborg and Jack Livingood discovered or characterized the radioisotopes iodine-131, cobalt-60, and several others.
In 1934, Wheeler and Breit calculated the probability that two colliding photons would create an elctron-positron pair. This prediction was confirmed in 1997 at the Stanford Linear Accelerator Center.
In 1934, Hubble and Milton Humason, in the course of adding more galaxy spectra, determined photographically that there were at least as many galaxies in the Universe as there are stars in the Milky Way. Hubble also reformulated his law log(V)=0.2m+B, where V is radial velocity, m is the apparent magnitude of the object and B is a constant which depends on Hubble's constant, or parameter, H, which is at present considered to be 50 to 100 kilometers per second per Megaparsec, the speed of an object's recession to its distance, plus the absolute magnitude of the object. It doesn't matter that the value of H is still controversial because the relative distances stay the same. A plot of this equation is known as a Hubble diagram and the slope 0.2 obtains the expected results for the laws of Einstein's General Theory of Relativity. It's also consistent with Friedman's model.
In 1934, Zwicky and Wilhelm Henrich Walter Baade advanced the idea that "a super-nova represents the transition of an ordinary star into a neutron star, consisting mainly of neutrons. Such a star may possess a very small radius and an extremely high density.... A neutron star would therefore represent the most stable configuration of matter as such" (Zwicky and Baade 1934:263).
Beginning in 1934, Konrad Zuse built a series of computers, Z1 through Z4, utilizing binary arithmetic and stored programs. "Along the way..., he invented the first programming language--the 'Plan Calculus,' or Plankalcül--and began to analyze methods by which a computer could play chess" (Waldrop 2001:40n).
In 1934, Gaston Bachelard, in Le Nouvel Esprit Scientifique, declared that "one may imagine the spin of an isolated electron, for example, but one does not think it. Thinking...depends on mathematical relations.... Objects have a reality only in their relations" (Bachelard 1934:132). All else is imagination.
In 1934, Karl R. Popper, in Logik der Forschung, advanced the theory that the test of an empirical system, the demarcation of the limit of scientific knowledge, is its 'falsifiability' and not its 'verifiability,' his aim being "to select the one which is by comparison the fittest, by exposing them all to the fiercest struggle for survival" (Popper 1934:42). To be falsifiable systems of statements must be logically precise and unambiguous, i.e., capable of being "subjected to tests which might result in their refutation" (ibid.:314).
In 1935, Boris Ephrussi and George Wells Beadle, by transplanting Drosophila parts, invented a general method of developmental genetics (Ephrussi and Beadle 1935). [added 02/01/03]
In 1935, Wendell Stanley and Northrop crystallized the tobacco-mosaic virus (Stanley 1935).
In 1935, N. Timoféeff-Ressovsky, K. G. Zimmer, and Max Delbrück wrote a paper entitled "On the nature of gene mutation and gene structure" (Timoféeff-Ressovsky 1935). In his theoretical contribution to this paper (which Schrödinger popularized ten years later), Delbrück pointed out that "whereas in physics all measurements must in principle be traced back to measurements of place and time, there is hardly a case in which the fundamental concept of genetics, the character difference, can be expressed meaningfully in terms of absolute units.... [And] the stability of [the well-defined union of atoms] must be especially great vis-à-vis the chemical reactions that normally proceed in the living cell; the genes can participate in general metabolism only catalytically" (quoted in Stent 1982:353-354). [revised 02/01/03]
By 1935, John Tileston Edsall and A. von Muralt isolated 'myosin' from muscle.
In 1935, William Cumming Rose recognized the essential amino acid 'threonine.'
In 1935, Szent-Györgi demonstrated the catalytic effect of dicarboxylic acids on respiration.
In 1935, Hugh Davson and James Frederick Danielli proposed a 'protein-lipid sandwich' model for the structure of cell membranes (Danielli 1935; Davson and Danielli 1943).
In 1935, [?] Knoll demonstrated the feasibility of a scanning electron microscope. [added 02/01/03]
In 1935, Gerhard Domagk discovered the efficacy of prontosil, the forerunner of sulfa drugs, in the course of treating streptococcal infections.
In 1935, Hideki Yukawa attempted to model the fundamental 'strong' nuclear force by analogy with quantum electrodynamics. This led to the prediction of the existence of the 'pion,' or 'pi-meson.'
In 1935, Einstein, Boris Podolsky, and Nathan Rosen, In "Can quantum-mechanical description of physical reality be considered complete?," proposed "a Gedanken-Experiment designed to show that the physical system had simultaneous properties that quantum theory could not determine, thereby demonstrating that the theory was 'incomplete,'" which allowed Einstein, et. al., to continue to adhere to the classical framework (Folse 1985:143). The implication of being incomplete is the need for additional, or hidden, variables. The goal is to have 'objective reality' "localized on each particle[:] If A and B have flown a very long way apart then..., at the very least, A cannot be directly affected instantaneously [by any disturbance of B], physical signal or influence can travel faster than light" (Davies and Brown 1986:15,14; Einstein et al. 1935:138-141).
In 1935, Watson-Watt designed the first workable 'radio direction finding,' or RDF, device for locating moving objects by bouncing radio waves off them and calculating the range by transmitted pulses. Independently, Rudolph Kühnold was working on a similar system, but only realized that pulse transmission was necessary some months later. It began to be called 'radar,' for 'radio detection and ranging,' after 1940.
In 1935, Albert W.Stevens and Orvil J. Anderson carried photographic plates on a balloon into the stratisphere, setting a record for manned flights. The developed plates showed the tracks of cosmic rays.
In 1935, IBM introduced a punch card machine with an arithmetic unit based on relays which could do multiplication.
In 1936, Pauling and Charles Coryell reported that hemoglobin undergoes a profound structural change when it combines with oxygen (Pauling and Coryell 1936).
In 1936, André Lwoff and Marquerite Lwoff, having discovered that bacterium required nutritional factors much like higher organisms and in the course of producing chemically defined media for their growth, discovered that growth factors, or vitamins, act as coenzymes, i.e., small molecules which assist enzymes in the performance of catalysis. [added 02/01/03]
In 1936, Carl Ferdinand Cori and Gerti Theresa Radnitz Cori discovered and isolated a new phosphorylated intermediate, glucose-1-phosphate, in carbohydrate metabolism (Cori and Cori 1936). [added 02/01/03]
In 1936, Edward Calvin Kendall and Phillip Showalter Hench discovered 'cortisone.'
In 1936, Egas Moniz designed the first prefrontal leucotomy to treat anxiety and agitation accompanying psychiatric conditions in humans.
In 1936, Gregory Bateson, in Naven, coined the term 'schismogenesis' to refer to escalating cycles in living systems that oscillate uncontrollably: "a process of differentiation in the norms of individual behavior resulting from cumulative interaction between individuals" (Bateson 1936:175).  
Beginning in 1936, Fritz Zwicky, using a Schmidt telescope, discovered twenty supernovas and identified the two main types. Supernovas are violent events, and only at this time did the peaceful, harmonius, Aristotelian view of the stars begin to change.
In 1936, Hubble, in The Realm of the Nebulae, described the Universe as extending out about 500 million light years. Subsequently, this distance has been revised upward several times, such that if our galaxy were represented by an aspirin the entire Universe would be a kilometer across (Gribbin 1998a:68).
In 1936, Felix Wankel designed a motor which revolved around a central shaft.
In 1936, Alan M. Turing published "On Computable Numbers," in which he developed the Turing machine, the abstact precursor of the computer. A Turing machine consists of a finite set of logical and mathematical rules and a tape of infinite length.
In 1936, Alonzo Church proved the thesis that any mental process, such as the brain or a computer, which divides numbers into two sorts can be described by some general recursive function. It is sometimes called the Church-Turing thesis.
In 1936, or earlier, Moritz Schlick, in Die Philosophie der Natur, noted that "one may not, for example, say that...the momentary state of actual present wanders along the time-axis through the four-dimensional world. For a wandering of this kind would have to take place In time; and time is already represented within the model and cannot be introduced again from the outside" (Schlick 1936:43).
In 1937, Edouard Chatton pointed out the cytological differences between organisms such as bacteria and blue-green algae, which he named 'prokaryotes,' and all other organisms, which he called 'eukaryotes.' [added 02/01/03]
In 1937, Neil Kensington Adam showed that elastic surface films are ubiquitous at the air-water interface (Adam 1937).
In 1937, Krebs discovered the citrus acid cycle, also known as the tricarboxylic acid cycle and the Krebs cycle. The citric acid cycle , that is, the breakdown of the carbohydrate pyruvic acid which citric acid catalyzes, accounts for about two-thirds of the total oxidation of carbon compounds in most cells. The process is cyclical because citric acid is regenerated and replenished. Its end products are CO2 and high-energy electrons, which pass via NADH and FADH2 to the respiratory chain (Krebs and Johnson 1937). [revised 02/01/03]
In 1937, James Papez proposed that the group of neurons that made up the anatomical substrate of the emotions was located in the limbic system (Papez 1937).
In 1937, Landsteiner put forth the view that when a foreign substance entered the body it was taken up by phagocytic cells where it served as a template against which globulin molecules could be synthesized. This theory was later falsified, i.e., disproved, but was appealing at the time because it explained away the paradox that a finite number of genes could generate a comparably vast diversity of antibodies.
In 1937, Tracy Morton Sonneborn worked out how to mate different strands of Paramecium, a ciliated protozoa, and detailed the interaction of the cytoplasm and the nucleus. By this time, hybridization techniques made the study of microorganisms accessible. Since they reproduced rapidly and did not undergo the complexity of tissue differentiation, they were superior subjects for the study of the chemistry of the organism.
In 1937, Haldane, influenced by Landsteiner's ABO blood groups, developed the 'one-gene, one-antigen' hypothesis, which entailed that distinctions between antigens could be traced to the encoding by specific genes of different alleles (Haldane 1937).
In 1937, Arne Wilhelm Kaurin Tiselius invented an electrophoresis apparatus which permitted the obtaining of much higher resolutions and the separation of charged molecules (Tiselius 1937a). The first experiments, carried out with horse serum, allowed the globulins to separate into three parts, alpha, beta, and gamma and further investigation showed they were different chemically and that the antibodies, or immunoglobulins, were found in the gamma globulin or between the beta and gamma globulins ( Tiselius 1937b). [added 02/01/03]
In 1937, Theodosius Dobzhansky's book, Genetics and the OrigIn of Species, detailed Wright's position on genetic drift, and echoed Sergei Chetverikov's position, from the 1920s, that nature uses heterozygotes to 'soak up' and preserve variation. Dobzhansky held that the unit of evolution was the population and that this fact greatly reduced the time required to respond to environmental changes.
In 1937, Warburg demonstrated how the formation of ATP is coupled with the removal of hydrogen atoms from glyceraldehyde 3-phosphate.
In 1937, Eugen Werle and colleagues discovered 'cytokinin,' a plant hormone which promotes cell division.
In 1937, P. A. Gorer discovered the first 'histocompatibility' antigens in lab mice (Gorer 1937).
In 1937, George William Marshall Findley and F. O. MacCullum discovered 'interferon,' a glycoprotein produced by cells in response to viral attack.
In 1937, V. M. Goldschmidt, in "Geochemische Verteilungsgesetze der Elemente," provided data on the relative abundance of chemical elements in meteors and stellar spectra.
In 1937, Zwicky calculated that "extragalactic nebulae offer a much better chance than stars for the observation of the gravitational lens effects" (Zwicky 1937:290). A gravitational lens is an intervening space-warping mass which acts as a virtual telescope as it amplifies the light from the more distant target.
In 1937, investigations into the properties of petrochemical polyamides by Wallace Hume Carothers resulted in the production of nylon fibers. His employer, DuPont, allied with the pulp wood industry, orchestrated a campaign to suppress competition from hemp fibers in the United States, under the guise of suppressing Cannabis sativa, and succeeded in making it illegal to grow that same year.
In 1937, Ivan Matveevich Vinogradov, in "Some theorems concerning the theory of prime numbers," proved that every sufficiently large integer can be expressed as the sum of three odd primes.
In 1937, Claude Shannon, in his Master's thesis, showed that relay circuits, being switches, resemble the operations of symbolic logic: two relays in series are and, two relays in parallel are or, and a circuit which can embody not and or can embody if/then. This last meant that a relay circuit could decide. Since switches are either on or off, binary mathematics was therefore possible (Shannon 1938).
In 1937, George Stibitz , working with the telephone companies electromechanical relays, demonstrated a one-bit binary adding machine.
In 1938, Herbert F. Copeland added a fourth domain, bacteria, to the taxonomy of the living world (Copeland 1938).
In 1938, McClintock described the bridge-breakage-fusion-bridge cycle in maize and predicted special structures on the ends of broken chromosomes, called 'telomeres' (McClintock 1938).
In 1938, the Coris described the catalytic process by which the body converts surplus sugar into storable glucogen by demonstrating the existence of a new enzyme, phosphorylase, that catalyzes the cleavage and synthesis of the glycosidic bonds of polysaccharides. Eventually, they were able to synthesize glycogen in a test tube. [added 02/01/03]
In 1938, Jean Louis Brachet demonstrated that ribonucleic acids are accumulated in regions of high morphogenetic development.
In 1938, a coelacanth, latimeria chalumnae, a primitive bony fish, known from Devonian fossils, was caught off Southeast Africa.
In 1938, Hans Spemann proposed the concept of cloning and insisted that cell differentiation was the outcome of an orderly sequence of specific stimuli, namely, chemical inductive agents, which were predominantly cyto-plasmic in operation (Spemann 1938).
In 1938, Warren Weaver coined the term 'molecular biology' (Weaver 1938).
In 1938, Otto Hahn and Lise Meitner, with their colleague Fritz Strassman, bombarded uranium nuclei with slow speed neutrons.  Meitner, after fleeing the Nazis and working with Otto Frisch, interpreted the Hahn-Strassman results to be 'nuclear fission,' the term fission being borrowed from biology.  They explained what happened in the nucleus by reference to the liquid drop model: "As the nucleus gets bigger, with more and more protons, the protons are farther apart, and the repulsive strength grows in comparison with the strong nuclear force, [and eventually] just enough to tip the balance in favor of the repulsive forces and split the nucleus" (Seaborg 2001:58-59).  They also calculated that vast amounts of energy would be released by a sustained chain reaction.  
In 1938, Carl F. von Weizsächer and, independently, H. Bethe proposed the existence of two chains of reaction by which the celestial conversion of hydrogen to helium is effected. These are the proton-proton cycle in less massive and luminous stars, and the carbon-nitrogen-oxygen cycle, in the most brilliant stars, where a minute amount of carbon acts as a catalyst, producing the nitrogen which is essential for life, i.e., the very same nitrogen nuclei which are now in your body (GribbIn and Gribbin 2000:108). After either of these processes has converted most of the star's hydrogen to helium, 'helium-burning' is initiated, and by the addition of helium the heavier elements are built up (through iron-56 and ultimately beyond that through bismuth-209 and the radioactive elements).
In 1938, Einstein, Leopold Infeld, and B. Hoffman, in their theory of the interaction of point masses with gravity, showed that the laws of motion of such particles follow from gravitational field equations.
In 1938, Pyotr Kapitsa and John F. Allen discovered that helium, when cooled within 2.2 kelvins of absolute zero, becomes a 'superfluid,' able to flow without friction. This effect occurs because up to about 10 percent of the helium atoms undergo Bose-Einstein condensation.
In 1938, Compton demonstrated that cosmic radiation consists of charged particles.
In 1939, J. Huxley introduced the notion to evolutionary studies of gradual change in a character, say size or color, over a geographic or ecological area. He termed this a 'cline.'
In 1939, Theorell isolated 'cytochrome c,' an enzyme responsible for energy reactions in mitochondria. [added 02/01/03]
In 1939, Siemens began production of commercial transmission electron microscopes. [added 02/01/03]
In 1939, Just, in The Biology of the Cell Surface, emphasized the changes in the ectoplasm during and after fertilization (Just 1939).
In 1939, C. Anderson discovered the 'mu-meson,' or 'muon,' one of a class of elementary particles, known as 'leptons.'
In 1939, Isadore Isaac Rabi and collaborators J. M. B. Kellogg, N. F. Ramsay, and J. R. Zacharias developed the "molecular-beam magnetic resonance method for measuring nuclear magnetic moments" (Kellogg et al. 1939:728).  This forms part of the basis for lasers, atomic clocks, and the measurement of the Lamb shift.  
In 1939, Szilard and Eugene Paul Wigner visited Einstein to discuss methods of averting a German atomic bomb. This led to Einstein's letter to the President of the United States.
In 1939, Szilard proposed stacking alternate layers of graphite and uranium in a lattice, the geometry of which would define neutron scattering and subsequent fission events.
In 1939, Grote Reber, with a 31 foot parabolic reflector in his back yard, confirmed Jansky's discovery of cosmic static.
In 1939, Oppenheimer and George Volkoff, in "On Massive Neutron Cores," concluded that stable neutron stars could only exist if they had masses in a range from 10 to 70 percent of the Sun. For masses, greater than this limit, "the star will continue to contract indefinitely, never reaching equilibrium" (Oppenheimer and Volkoff 1939:381).
In 1939, Gamow, using a Hertzsprung-Russell diagram, suggested that stars evolve upward along the diagram as they slowly deplete their hydrogen fuel.
In 1939, Oppenheimer and Hartland Snyder, in "On Continued Gravitational Contraction," using Schwarzschild's solution to Einstein's equation, described the formation of black-holes: "When all the thermonuclear sources of energy are exhausted a sufficiently heavy star will collapse.... The radius of the star approaches [its Schwarzschild] radius [and] light from the star is progressively reddened" (Oppenheimer and Snyder 1939:455). They also pointed out that there were two incompatible views, inside and outside, of black-hole formation: For an observer outside the black-hole the collapse takes almost forever, while inside a co-mover perceives the collapse as "finite, and...of the order of a day" (ibid.:455).
In 1939, Bush proposed an associative information retrieval system which he called 'Memex' and which is ancestor to 'hypertext' and the 'World Wide Web.' He foresaw this operating on an electric analog computer, which was completed in 1942.
In 1939, Stibitz and Samuel B. Williams designed and built the binary 'Complex Computer,' actually more of a desktop calculator, "equiped with 450 relays and three modified Teletype machines for entering problems and printing out the answers" (Waldrop 2001:35).
In 1939, John Vincent Atanasoff and Clifford Edward Berry began to build a protp-type 16-bit adding machine which used vacuum tubes and had a circuit that could store binary numbers until needed.
In 1939, Nikolai Sergei Trubetzkoy's Grundzüge der Phonologie, which contains his theory of distinctive phonemic oppositions, was published posthumously (Trubetzkoy 1939).
In 1940, Pauling suggested, in support of the immunochemical template theory, that the specificity of an antibody is the result of complementariness between its structure and a portion of the surface of the homologous antigen. In other words, this complementariness is induced by the antigen into the variable folding patterns and noncovalent bonds of the antibody after protein systhesis has already taken place (Pauling 1940).
In 1940, Herman Moritz Kalckar and Vladimir Aleksandrovitch Belitser discovered 'oxidative phosphorylation,' a coupled electron-transfer reaction by which ATP is regenerated (de Duvé 1991:13-14).  
In 1940, Ernst Boris Chain and Howard Walter Florey extracted and purified penicillin and demonstrated its therapeutic utility.
From the work of Torbjörn Caspersson, published in 1940 and 1941, and Brachet, published in 1942, the association of RNA with cell growth was established (Judson 1979:641n236; Caspersson 1946; Brachet 1946).
In 1940, Landsteiner and colleagues found the Rhesus factor, a variant on the surface of red blood cells of most human beings, i.e., those that are Rh+ (Landsteiner and Weiner 1940).
In 1940, de Beer wrote Embryos and Ancestors, a refutation of Haeckel's biogenetic law.
In 1940, Edwin M. McMillan and Phillip H. Abelson discovered the first transuranium element 'neptunium,' a byproduct of uranium decay.
In 1940, Georgii Flerov and Konstantin Petrzhak discovered the spontaneous fission of uranium.
In 1940, Urey became director of the United States government program to separate uranium isotopes. In the course of this, he developed statistical methods of isotope separation which permitted large scale production of uranium235.
In 1940, Norbert Wiener proposed building vacuum-tube electronic computers which would make totally preprogrammed digital calculations using binary mathematics on magnetic tape (Wiener 1940).
In 1940, Igor Sikorsky invented the heliocopter.
Beginning about 1940 [?], Roman Jakobson propounded the theory that the sounds of all human languages are composed of atomic units, which he called 'features,' that all human beings innately possess the biological bases of these features, and individual languages are subsets of them. Language acquisition involves the "activation of the particular features that a given language uses; as people mature, they lose the unused ones" (Lieberman 1991:37).
In the 1940s, Wilhelm Reich proposed that cancer results from repressed emotions, especially those related to sexual desires.
In 1941, Haldane speculated that the self-reproduction of the gene could be demonstrated by labelling the gene and then seeing if the copy gene contained the label while the original did not (Haldane 1941:44).
In 1941, Fritz Albert Lipmann, using a bacterium that clots milk, proposed that adenosine triphosphate takes energy out of the metabolic flow and conducts it to reactions where needed. This was a radical sharpening of the idea of specificity (Lipmann 1941).
In 1941, Astbury established the DNA has a crystalline structure.
In 1941, George Wells Beadle and Edward Lawrie Tatum, using the bread mold Neurospora crassa, published the assertion that genes control cells by controlling the specificity of enzymes, i.e., one gene controls one enzyme so a mutation in a gene will change the enzymes available, causing the blockage of a metabolic step. A major advantage of Neurospora over Paramecium is that the former can be grown on defined, preferably, synthetic medium, e.g., manufactured vitamins and amino acids, whereas the latter must have bacteria (Beadle and Tatum 1941).
In 1941, Burnet, reviving ideas of Metchnikoff, focused on two experimental facts incompatible with the template hypothesis: "the continued production of antibody in the absence of antigen, and the presence of the secondary response, in which a second inoculation with an antigen elicits a host response qualitatively more rapid than that which followed the first inoculation" (Podolsky and Tauber 1997:27).
IIn 1941, Northrop produced a crystalline antibody to diphtheria. [added 02/01/03]
In 1941, Bush became director of the United States Office of Scientific Research and Development where he directed such programs as the mass production of sulfa drugs and penicillin, the development of the atomic bomb, and the perfection of radar. As part of the latter effort, Karl Lark-Horowitz, Seymour Benzer, and others developed germanium crystal rectifiers, the semiconducter later used in transistors. Atomic bomb development was known as the Manhattan Project with Oppenheimer in overall charge of the scientists involved.  
In 1941, Seaborg, McMillan, Joe Kennedy, and Arthur Wahl deduced from secondary evidence the existence of a trace amount of 'plutonium,' transuranium element 94, which they made from uranium-238.  "That increased the potential material available for a bomb by a hundredfold" (Seaborg 2001:78).  Moreover, its fission rate was greater than U-235 and a fissionable isotope employed in the bomb dropped on Nagasaki.
Beginning in 1941, Lev Davidovic Landau constructed a complete theory of the quantum liquids at very low temperatures.
In 1942, Waddington described 'canalization,' the capacity to respond to an external stimulus by some developmental reaction, such as the formation of an ostrich's calloses, which are under genetic control. "Once a developmental response to an environmental stimulus has become canalized, it should not be too difficult to switch development into that the internal mechanism of a genetic factor...; the same considerations which render the canalization advantageous will favor the supercession of the environmental stimulus by a genetic one. By such a series of steps, then, it is possible that an adaptive response can be fixed without waiting for the occurrence of a mutation which...mimics the response well enough to enjoy a selective advantage" (Waddington 1942:565).
In 1942, J. Huxley wrote Evolution, The Modern Synthesis, which lent its name to the 'modern synthesis' of evolutionary studies created by Fisher, Haldane, and Wright. It received its name because it "gathered under one theory--with population genetics at its core--the events in many sub-fields that had previously been explained by special theories unique to that discipline. Such an occurrence marks scientific 'progress' in its truest sense--the replacement of special explanations carrying little power in prediction or extension with general theories, rich in implications and capable of unifying a diverse set of phenomena that had seemed unrelated" (Eldredge and Gould 1971:108).
In 1942, Ernst Mayr, in writing Systematics and the Origin of Species against the 'typological' species concept, did for systematics what Dobzhansky had done for genetics. Later, he came to deny the likelihood of any gene remaining selectively neutral, i.e., available for random drift, for any length of time.
In 1942, Szent-Györgi and colleagues showed that myosin was not the sole structural protein in muscle, but shared that role with 'actin,' the complex of the two being named actomyosin. They also showed that threads of actomyosin, in the presence of magnesium and potassium ions, contracted with the addition of adenosine triphosphate (ATP).
In 1942, J. Weiss discovered ionic 'charge transfer.'
In 1942, Fermi, pursuant to scaling-up the creation of plutonium 239, created the first controlled, self-sustaining nuclear chain reaction from 'piles,' Szilard's lattice, of uranium and graphite.  The term pile has been superseded by 'reactor.'  This was accomplished as part of the Manhattan Project, of which Compton was in charge of the Metallurgical Laboratory and under him Fermi commanded the physicists and Seaborg the chemists.  
In 1942, Rudolph Minkowski, in "The Crab Nebulae," pointed out that "sufficient mass is blown off from the stellar envelope during the supernova explosion to allow the remnant star to stop its collapse at the white dwarf stage" (Lang and Gingerich 1979:482).
In 1942, Wiener, Julian Bigelow, and Arturo Rosenblueth explained that all voluntary action involved feedback, that "the processes of communication and control are based on the much more fundamental notion of message, [that] the nervous system [is an] array of feedback loops in active communication with the environment, [and that] through feedback...a mechanism could embody purpose" (Waldrop 2001:56). In other words, the mind, purposeful spirit, is inextricably bound up with the body, with matter.
In 1943, bacterial genetics was born with the publication of the paper by Eduardo Salvatore Luria and Delbrück, the core of the so-called 'phage group,' reporting evidence that mutation, not adaption, was how bacteria acquired resistance to phage and that mutation was revealed through its selection: "When a pure bacterial culture is attacked by a bacterial virus, the culture will clear after a few hours due to destruction of the sensitive cells by the virus. However, after further incubation for a few hours, or sometimes days, the culture will often become turbid again, due to the growth of a bacterial variant which is resistent to the action of the virus" (Luria and Delbrück 1943:491). Nine months later Jacques Lucien Monod and Alice Audureau demonstrated similar results which were published at the end of the war(Monod and Audreau 1946). Many people believed the resistance of bacteria to antibiotics was the result of some sort of adaption induced by the antibiotic, which implied that acquired characteristics could be inherited (Monod et Audureau 1946).
In 1943, Sonneborn discovered the cytoplasmic factor Kappa, which he was able to control through effecting the environment (Sonneborn 1943).
In 1943, Thomas Francis and Jonas Edward Salk developed a formalin-killed-virus vaccine against type A and B influenzas. [added 02/01/03]
In 1943, Albert Hofmann ingested the ergotomine molecule, lysergic acid 25 (LSD-25), which he had synthesized in 1938.
In 1943, Kenneth Craik, in The Nature of Explanation, said "the brain functions like a simulator [which] gives to thought its power to predict events and to anticipate their sequence in time" (Changeux 1983:134). [added 02/01/03]
In 1943, Warren S. McCulloch and Walter H. Pitts published "A Logical Calculus of the Ideas Immanent in Nervous Activity," where they claimed that the brain could be modelled as a network of logical operators on a Turing machine. This initiated discussions which led to the use of computational metaphors and Boolean functions in the study of cognition.
[In the early, mid-1940s, there were two distinct approaches to understanding the nature of life, functional and structural. The proponents of a functional description were biochemists--Avery and Erwin Chargaff--and geneticists--Luria, Delbrück, Alfred Hershey, and Monod. The chief proponents of the structural approach, that is, characterizing the chemical sequences of the large, long-chain protein molecules and, stereochemically, reconstructing their three-dimensional architecture, were Bragg, Pauling, Astbury, and Bernal].
In 1944, through the experiments of Oswald T. Avery, Colin MacLeod, and Maclyn McCarty, it was established that the material of heredity, specifically in Griffith's dead pneumococci, was deoxyribonucleic acid. In other words, even though they were dead, the cells could transfer their genes as long as their DNA remained intact. Up to this time, most biologists thought genes were probably protein and nucleic acid was some sort of skeletal material for the chromosomes (Avery et al. 1944).
In 1944, Peter B. Medawar proved the immunological nature of graft-rejection (Medawar 1944).
In 1944, Selman Waksman discovered streptomycin.
In 1944, George Gaylord Simpson, in Tempo and Mode in Evolution, argued that no observations in the fossil record required 'inherent forces,' or orthogenesis, toward 'desired ends,' e.g., large size.
In 1944, Robert Burns Woodward and William E. Doering announced the 'total synthesis' of quinine. Total synthesis occurs when a molecule is built up from the smallest, most common compounds. Over the next eighteen years, Woodward synthesized, in 1951, cholesterol and cortisone, in 1954, strychnine and lysergic acid, in 1956, reserpine, in 1960, chlorophyll, and, in 1962, a tetracycline antibiotic. [added 02/01/03]
In 1944, Archer John Porter Martin and Richard Synge devised, 'paper partition chromatography,' in which solutions move in columns on sheets of paper instead of in tubes packed with absorbent materials. [added 02/01/03]
In 1944, Seaborg proposed a second 'lanthanide group' as an addition to the periodic table of the elements.  Lanthanum is element 57 and the lanthanide group consists of elements 58 through 71.  Actinium, immediately below lanthanum in the periodic table, is element 89 and Seaborg proposed the existence of a similar series, 90 through 103, or 'actinide group.'  This led, in the course of the next twenty years, to the isolation of elements 95 through 106 and about 150 isotopes, in each case with the participation or under the leadership of Albert Ghiorso.
In 1944, L. Onsager published a complete solution for the two-dimensional Ising model.
In 1944, Szilard proposed the term 'breeder' to describe a reactor able to generate more fuel than it consumed.
In about 1944, Stanislaw Marcin Ulam and Edward Teller, both working on the Manhattan Project, suggested a two-stage radiation implosion design, employing both fusion and fission, permitting the detonation of thermonuclear weapons.
In 1944, Reber found discrete sources of radio emission in the direction of Cynus and Cassiopeia.
In 1944, Hendrick van de Hulst and Jan H. Oort pointed out that radio telescopes can sample more distant regions of the Universe than optical telescopes. Radio telescopes usually have a parabolic reflector, which works in a manner similar to the main mirror of an optical telescope.
In 1944, Howard W. Aiken and a team of engineers from IBM displayed a huge programmable calculator, the 'Automatic Sequence Controlled Calculator,' later known as the 'Mark I.'
In 1944, von Neumann and Oskar Morgenstern, using zero-sum parlor games like poker and chess, published their formulation of game theory in reference to human economic behavior.  The central assumptions are that the players are able to foresee the consequences of their actions and will behave rationally, and according to some criterion of their self-interest.  About the same time, von Neumann applied game theory to United States nuclear strategy, which led to his being characterized, along with Teller, as Dr. Strangelove in Stanley Kubrick's movie.
In 1944, Hayek, in The Road to Serfdom, argued that no central economic planner could possibly command the countless bits of localized and individual information necessary and that only the unorganized price system in a free market enables order to arise from the myriad of individual plans.
In 1945, Schrödinger, in What is Life?, asked questions about replication, structure, aperiodicity, coding, and metabolism which set biology's agenda for 30 years.
In 1945, Ray Owen demonstrated that identical cattle twins, i.e., who had shared an in utero circulatory system, were unable, in adulthood, to mount an immune response to antigens produced by the twin. This was the first demonstration of immune tolerance.
In 1945, Michael James Denham White, in Animal Cytology and Evolution, the first monograph on cytogenetics, gathered together prior research on chromosomes and the various sorts of mitotic and meiotic mechanism. New editions kept this synthesis together through 1971 (White 1973).
In 1945, Wright devised the 'Coefficient of Relationship', which represents in numerical form the genetic probabilities for related members of a population to carry replica genes. There are just three possible conditions of this in an individual, namely, that both, one only, and neither of his genes, at a given locus, are identical by descent, or c2+c1+c0=1. The relationship is completely specified by any two of them, e.g., 2c2+c1. One-half of this number, c2+1/2c1, may therefore be called the expected fraction of genes identical by descent in a relative.
In 1945, Maurice Merleau-Ponty, in the Phénoménologie de la Perception, asserted that the foundations of science entail the primacy of perception as against the older 'retinal image + judgement = perception as hypothesis.'
In 1945, van de Hulst, in "Heromst der radiogolven uit het wereldruim," discussed the possibility of discrete lines in the spectrum of cold, neutral, interstellar hydrogen and correctly predicted its appearance at 21 cm.
In 1946, Joshua Lederberg and Tatum discovered that the bacteria Escherichia coli sometimes exchange genes (Lederberg and Tatum 1946).
In 1946, L. Michaelis proposed that free radicals were obligate intermediaries in metabolic pathways in living cells.
In 1946, U.v. Euler deteched a neurotransmitter, 'noradrenaline,' in the sympathetic nervous system. [added 02/01/03]
In 1946, Landau postulated an attenuation, or 'damping,' of wave motion when the velocity of a wave is comparable to the velocity of electrons in 'plasmas.' A plasma forms when electrons are separated from their nuclei by heat.
In 1946, Willard Frank Libby developed radioactive carbon-14 dating, employing the known rate of decay, measured by its half-life, and relative proportion of its decay products.
In 1946, Martin Ryle and Derek D. Vonberg were "the first In radio astronomy to employ an antenna configuration analogous to Michelson's optical interferometer. They soon demonstrated how source sizes in radio astronomy may be estimated by measuring the fringe amplitudes associated with various spacings of the receiving elements" (Sullivan 1982:182), or, in other words, "two aerial systems were used [to observe the sun] with a horizontal separation of several wave-lengths, and their combined output was fed into the receiving equipment" (Ryle and Vonberg 1946:339). "The maximum resolution of the array is...determined not by the size of the individual elements, but by their maximum separation. Interferometers are [used] also in infared and optical astronomy [where] the incoming beam is split and then recombined with itself to form an interference pattern" (Dictionary of Astronomy 1997:238).
In 1946, Robert H. Dicke, in order to reduce the noise from a radio telescopic receiver, described an alternating on-off switch which produces "greatly improved accuracy and effective sensitivity" (Sullivan 1982:105).
In 1946, James S. Hey, S. J. Parsons, and J. W. Phillips, in "Fluctuations in Cosmic Radiation at Radio Frequencies," announced their discovery of a discrete radio source from the direction of the constellation Cygnus A.
In 1946, Gamow suggested that the relative abundances of the elements were determined by nonequilibrium nucleosynthesis during the early stages of the Universe's expansion.
In 1946, Fred Hoyle suggested that collapsing stars will continue until, reaching Chandrasekhar's limit, they become rotationally unstable and throw off the heavy elements which they have built up and that "the observed intensity of cosmic rays can be explained by means of such an association" (Hoyle 1946:384).
In 1946, John Mauchly and John Presper Eckert, trying to more quickly ascertain artillery shell trajectories for the United States War Department, demonstrated ENIAC, or Electronic Numerical Integrator and Computer. Its components were entirely electronic.
In 1946, von Neumann, Arthur W. Burks, and Herman Goldstine, in "Preliminary Discussion of the Logical Design of an Electronic Computing Instrument," going out of their way to use biological metaphors, defined the concept of a software program and showed how a computer could execute such a program by , stored in a binary-code random-access memory unit, by obeying instructions of a central control unit. This ' von Neumann architecture,' drawing its circuit designs using McCulloch-Pitts neural-net notation with its sharp distinction between software and hardware, is the basis for almost all computers today.
In 1947, Bernal, in a speech on "The Physical Basis of Life," proposed that the lagoons and pools at the edge of the oceans served to concentrate the chemical building blocks and raised the possibility of these chemicals being further concentrated by being absorbed on particles of clay (Bernal 1947).
In 1947, Paul Weiss published his concept of 'molecular ecology,' which involves the functional role of the cell surface and 'fields' of chemical and physical conditions: "Let the number of [molecules] keep on increasing..., and all of a sudden a critical stage arises at which some of the [molecules] find themselves...cut off completely from contact with their former vital environment by an outer layer of their fellows.... Thus would ensue a train of sequelae of ever-mounting, self-ordering complexity.... The fate of a given unit would be determined by its response to the specific conditions..., [which vary] locally as functions of the total configuration of the system--its 'field pattern,' for short" (Weiss 1967:819-820).
In 1947, John Tyler Bonner published a study of chemotaxis in slime mold, demonstrating that the interaction of chemical messages and receptors produces their aggregation in a complex organization.
In 1947, Ilya Prigogine, inÉtude thermodynamique des phénomènes irrèversibles, dealt with the constructive role of time, i.e., irreversibility, and self-organization in open thermodynamic systems.
In 1947, Louis Werner and Israel Perlman isolated element 96, curium.  
In 1947, John Bardeen, Walter H. Brattain, and William Schockley invented the point-contact transistor amplifier, a voltage and current amplifier, which, in contrast to the vacuum tube it replaced, is an arrangement of semiconductor materials sharing common physical boundaries. A semiconductor is a solid material, e.g., silicon, in which certaIn induced impurities enhance its conductive properties.
In 1947, Willis Eugene Lamb and R. C. Retherford found a slight difference of energy between the state of zero angular momentum and the first excited state of hydrogen. Known as the 'Lamb shift,' it results from the quantum interaction between an electron and atomic radiation.
Later in 1947, H. Bethe noticed that calculations of mass and energy, for example, for the Lamb shift, in the theory of quantum electrodynamics (QED), Dirac's equation of 1929, conformed more closely to their experimental values the closer to zero distance the calculation of the 'coupling points' is carried.
In 1947, George Rochester and C. C. Butler discovered a cosmic particle which they named ' V.'
In 1947, Dennis Gabor invented 'holography,' a method of displaying a three-dimensional image of an object by splitting a coherent light beam so that some of it falls on a photographic plate and the rest on the object which reflects back onto the photographic plate. The two beams form an interference pattern on the plate with alternating light and dark. "The light is where the two images both relect light back and reinforce each other, while the dark is where the images do not match" (van Dulkin 2000:112). The plate is then developed, creating a 'hologram,' Greek for 'completely written.'
In 1947, Langmuir proposed that non-linearities in weather phenomena made them unstable when subjected to small changes in their energy cycles.
In 1948, Burnet and Frank Fenner hypothesized that the immune system discriminated between 'self' and 'nonself' (Burnet and Fenner 1949).
In 1948, George David Snell and Peter Gorer, transplanting tissues between mice, discovered a genetic factor, which they called H-2, for 'histocompatibility two.' [added 02/01/03]
In 1948, William Howard Stein and Stanford Moore isolated amino acids by passing a solution through through a chromatographic column filled with potato starch. [added 02/01/03]
In 1948, Sin-itiro Tomonaga, Victor Weisskopf, Julian Seymour Schwinger, and Richard Feynman, each independently, invented different methods of making precise the renormalization calculations of the QED. These methods invoved various ways of smothering the unwanted infinities in calculating the Lamb shift. "The essence of renormalization is to make the transition from one level of description to the next.... It is when you solve the field equations that you see the emergence of particles. But the properties--the mass and the charge--that you ascribe to a particle are not those inherent in the original equation" (Schwinger, quoted in Gleick 1992:262). Continuing into 1949, Feynmann published numerous papers in which he completed the mathematics of QED with 'Feynman diagrams,' applicable, for example, In the chemistry "to those problems in which the heavy nuclei can be approximated as fixed point particlescarrying an electric charge" (Gell-Mann 1994:110). In the late 1960s, Feynman diagrams proved essential in quanticizing gauge theories (Feynman 1985:127-128).
In 1948, Marya Goeppert-Meyer and, independently, Hans Jensen proposed the 'shell' structure of the nucleus in which the nucleons are assumed to move in shells analogous to atomic electron shells, or levels.
In 1948, Gamow and Ralph A. Alpher, in "The Origin of Chemical Elements," predicted that an adiabatic thermodynamic radiation event would have produced a background of microwave radiation with a temperature of five degrees K and would have provided the non-equilibrium conditions necessary for the successive captures of neutrons by protons which formed the elements. Gamow assumed the cosmic ylem, the primordial matter, consisted of neutrons with a temperature of ten billion degrees (Alpher et al. 1948:803-804). Later that year, the theory was further developed by Alpher and Robert C. Herman. Also, the same year, in opposition to this theory, Herman Bondi, Thomas Gold, and, independently, Hoyle promulgated a 'Steady-State' theory of the Universe, i.e., there is no beginning and matter is continuously created to fill in the gaps left between the old galaxies. The standard form of de Sitter's 1917 solution reappears as the line element in this theory. In other words, they rationalized Hubble's redshift as a local phenomena (Bondi and Gold 1948:258, 262; Hoyle 1948:379-380). However, they did not account for the possibility of background radiation temperature.
In 1948, von Neumann observed that replication and metabolism are logically separable, and, in fact, are analogous processes to software (nucleic acid) and hardware (protein).
In 1948, Shannon, in A Mathematical Theory of Communication, proposed a linear schematic model of communications, defining the fundamental problem of communication as the task of reproducing at one point In space a message created at another point. He worked out how such a message could be reliably sent, the theoretical limit of the amount of information it could contain, and contributed the notion of negentropy as a measure of information, thereby creating 'information theory.' The word 'bit,' short for binary digit, and credited to John Tukey, was used in print for the first time.
In 1948, Wiener, in Cybernetics, or Control and Communication in the Animal and Machine, which dealt with general communications problems, said that living organisms are metastable Maxwell demons whose "stable state is to be dead" (Weiner 1948:72).  Weiner coined 'cybernetics,' in honor of Maxwell's paper "On Governors," from the Greek for 'steersman,' from which the word 'governor' is descended.
In 1949, Victor Negus and Arthur Keith reconstructed the supralaryngeal airways of a Neanderthal fossil and concluded that its tongue was closer to that of a chimpanzee than a human and that it lacked a pharynx, or soft palate.
In 1949, Ivan Ivanovich Schmalhausen's Factors of Evolution: The Theory of Stabilizing Selection was translated into English by Dobzhansky and so associated with the 'modern synthesis.' He offered two versions of stabilizing selection. The first, which the modern synthesis adopted, built up "the mean or average form by selecting against the extremes at both ends of the distribution" (Gottlieb 1992:133). The second saw evolution as a process where, in the course of severe environmental pruning and breeding among the survivors, the traits which enabled survival, the 'adaptibilities,' might be assimilated genetically. This is similar to the Baldwin effect and Waddington's 'genetic assimilation.'
In 1949, Sven Furberg ,in his dissertation for Birbeck College, London,drew a model of DNA, setting sugar at right angles to base, with the correct three-dimensional configuration of the individual nucleotide.
In 1949, Frederick Sanger made the claim that proteins are uniquely specified, the implication being that, as there is no general law for their assembly, a code was necessary.
In 1949, Szent-Györgyi showed the isolated myofibrils from muscle cells contract upon the addition of ATP.
In 1949, Pauling discovered the molecular nature of sickle-cell anaemia (Pauling et al. 1949).
In 1949, Donald Hebb suggested in Organization of Behavior that selective reinforcement of neural connecions accounts for learning and memory. Moreover, this reinforcement causes the brain to organize itself into 'cell assemblages,' the building blocks of information. Since any given neuron would belong to several such assemblages, the activation of one assemblage would activate others, creating larger concepts and more complex behaviors.
In 1949, Jerzy Konorski suggested that memory is the result of functional transformations, or plastic changes, in neurons.
In 1949, George A. Miller and Frederick Frick, writing on the uses of information theory in psychology, noted that "what a person expects to hear is critical to what he does hear" (Miller, quoted in Waldrop 2001:97).
In 1949, Brillouin proposed an information theoretical refutation of Maxwell.
In 1949, Freeman Dyson, in several papers, unified Feynman's and Schwinger's radiation theories, emphasizing the so-called 'scattering matrix,' which contained the different routes from the initial state to a given end-point.
In 1949, Francis Bacon invented a fuel cell employing only hydrogen and water.
In 1949, John G. Bolton, Gordon J. Stanley, and O. B. Slee identified three discrete radio sources: Taurus A in the Crab Nebulae, Virgo A, and Centaurus A.
In 1949, another Hale telescope, the 200-inch mirror on Mount Palomar, was completed.
In 1949, Gödel, in "A Remark about the Relationship between Relativity Theory and Idealistic Philosophy," reported his discovery of solutions for the field equations of General Relativity that described worlds, which he calls 'rotating universes,' in which it is possible to travel into the past "exactly as it is possible in other worlds to travel to distant parts of space" (Gödel 1949:560).  
In 1949, Gilbert Ryle, in Concept of Mind, held that the mind is part of the body's activity, not a separate and theoretically equivalent counterpart to the body, not "a ghost in a machine" (Ryle 1949:15).
In 1950, Chargaff showed that the tetranucleotide theory was wrong, In other words, that DNA did not consist of a monotonous succession of nucleotides (in a fixed order in sets of four), and that the molecule to molecule "ratio of total purines to total pyrimidines, and also of adenine to thymine and of quanine to cytosine, were not far from 1" (Chargaff 1950:13). The collapse of the tetranucleotide theory made it highly likely that nucleic acids were also sequentially specific.
In 1950, Cyril Hinshelwood published his derivation of the biological activity of a three-dimensional protein strictly from its one-dimensional sequence (Caldwell and Hinshelwood 1950).
In papers of 1950 and 1951, McClintock, working in the genetics of maize, reported finding control elements, providing the first evidence that genetic regulation might be universal. She found evidence that some genes move from place to place and often affect nearby genes. In the mid-1970s, these genes were isolated and named transposons (McClintock 1950; McClintock 1951).
In 1950, George Ledyard Stebbins wrote Variation and Evolution in Plants.
In 1950, Lwoff , Louis Siminovitch, and Niels Kjeldgaard, succeeded in 'inducing' Bacillus megaterium, a lysogenic bacteria, to produce virions, or bacteriophage, by irradiation. This established that viruses have a dormant or noninfective stage, which they called 'prophage,' reproducing along with each cycle, and are thus intimately associated with the genetic material of their hosts (Lwoff et al. 1950; Lwoff 1992). Lwoff speculated that animal-cell viruses function in the same way. [revised 02/01/03]
About 1950, Boris Belousov discovered serendipitously a non-living chemical oscillator which came to be known as the Belousov-Zhabotinsky reaction.
In 1950, Karl von Frisch discerned the code which is conveyed by the dance of bees (Frisch 1951; Frisch 1965).
In 1950, Ernst L. Wynder and Evarts A. Graham published, in the Journal of the American Medical Association, a survey indicating a strong correlation between contracting lung cancer and smoking tobacco.
In 1950, Leo Rainwater combined the liquid drop and shell models of the atomic nucleus.
In 1950, Chushiro Hayashi showed that neutrons will interact with thermally excited positrons to form protons and antineutrinos and "determined the value of the proton-neutron ratio resulting from spontaneous and induced beta processes" (Alpher et al. 1953:1348).
In 1950, Fred L. Whipple, in "A Comet Model. I: The Acceleration of Comet Encke," hypothesized a great difference between comets and meteors: "A model comet nucleus...consists of a matrix of meteoric material with little structural strength, mixed together with frozen gases, a true conglomerate.... We know very little about the meteoric material except the pieces seem to be small [and] physically the meteoric material is strong enough to withstand some shock in the atmosphere.... As our model comet nucleus approaches perihelion, the solar radiation will vaporize the ices near the surface [and] meteoric material below some limiting size will be blown away" (Whipple 1950:376-377).
In 1950, Karl Otto Kiepenheuer and, independently, Hannes Alfvén and Nicolai Herlofson hypothesized that cosmic radio emissions come from discrete electromagetic sources with magnetic fields moving at extremely high speeds, close to that of light. Such radiation is known as 'synchrotron radiation.' Until this time, most assumed that radio interference was only a type of decelerating thermal radiation, known as 'bremsstrahlung,' which is German for 'breaking radiation.'
In 1950, Fermi and A. Turkevich, having examined all the thermonuclear reactions that might have led to element formation, concluded that no element heavier than helium could have been produced in a nonequilibrium primal fireball.
In 1950, Oort proposed that comets originate in a cloud of particles, perhaps, a light-year from the Sun and that upon occasion are deflected into the Solar System after being gravitationally perturbed by a passing star.
In 1950, Hoyle claims to have coined 'big-bang' for the primal fireball, disparaging the notion that such ever occurred (Hoyle 1994:255).
In 1950, John Forbes Nash, in "Non-cooperative Games," introduced "the concept of the non-cooperative game and develope[d] methods for the mathematical analysis of such games" (Nash, quoted in Kuhn et al 1995:5).  Generalizing the minimax solution introduced by von Neumann in 1928 for the two-person zero-sum game, Nash proved that "every non-cooperative game has at least one equilibrium point..., such that no player can improve his payoff by changing his mixed stategy unilaterally" (Ibid.:5).  In other words, the basic requirement for constituting an equilibrium is the stabilization of the frequencies with which the various stategies are played.  
In 1950, David Huffman devised an algorithm by which any set of symbols can be compressed in everything from compact discs to interplanetary spacecraft (Waldrop 2001:94n).
In the 1950s, John Robinson distinquished between gracile and robust Australopithecus in functional terms, which he suggested are somewhat analogous to the differences between chimpanzees and gorillas, and suggested that the gracile type was ancestral to hominids.
In 1951, Pauling discovered by crystallography that an alpha helix, a twisted polypeptide chain, is the basic structure of many proteins. Successive turns of the helix are linked by hydrogen bonds (Pauling et al. 1951).
In 1951, Lederberg and Norton Zinder announced that in order to become lysogenic bacteria need not wait for a mutation to arise if they can pick up a gene for resistence from another strain, a phenomena they called 'transduction' (Zinder and J. Lederberg 1952). In the same year, Esther Lederberg proved that lysogeny could be transmitted in bacterial crosses like any other genes (E. Lederberg 1951).
Later in 1951, Monod, Germaine Cohen-Bazire, and Melvin Cohn, with an array of artificial b-galactosides, learned to decouple the production of the enzyme from its natural stimulus and from the natural substrate, lactose, and called the process 'induced enzyme synthesis,' or just 'induction.' Subsequent work established that enzyme induction consists in the actual synthesis from amino acids of the entire enzyme molecule, and that this protein is stable, not 'dynamic,' as many thought(Monod et al. 1951).
In 1951, Carl Djerassi synthesized 19-nor-17a-ethynyltesterone, or norethindrone, an inhibitor of ovulation when taken orally.
In 1951, Erwin Mueller invented the field-ionization microscope.
In 1951, Otto Struve suggested the transit method of planet detection: In stars with a fortuitous alignment with the Earth, when a planet transits, or eclipses, the star, it will dim slightly.
In 1951, Ryle described a phase-switched, or Dicke-switched, radio interferometer which "enables the radiation from a weak 'point' source such as a radio star to be recorded independently of the radiation of much greater intensity from an extended source.... It also has important applications to the measurement of the angular diameter and polarization of a weak source of radiation" (Ryle 1952:351).
In 1951, George H. Herbig and, independently, Guillermo Haro reported finding faint gas clouds within the constellation Orion. These are known now as Herbig-Haro objects.
In 1951, Ernst Öpik and, independently, the following year, EdwIn E. Salpeter presented arguments for the synthesis of carbon and other heavy elements by helium burning in the interiors of stars: Under suitable temperatures, beryllium 8 is "formed momentarily by the collision of two [helium] alpha particles [that] can capture a third one before breaking up [back] into two alpha particles, and thus carbon 12 can be synthesized" (Lang and Gingerich 1979:375).
In 1951, Francis Graham Smith, using the Cambridge interferometer, was able to communicate highly accurate positions for discrete radio sources to Baade and Minkowsky who, using the Mount Palomar optical telescope and a spectroscope, unambiguously confirmed the identity of the two strongest radio sources in the sky, Cassiopeia A and Cygnus A.
In 1951, Ludwig F. Biermann suggested that the ion tails of comets, which always stream away from the Sun, "are accelerated by a moving plasma of solar origin and proposed that the Sun emits a continuous flow of solar corpuscles of the same type as those causing geomagnetic storms" (Lang and Gingerich 1979:147).
In 1951, Jay Forrester and Robert Everett, working for the United States Navy, completed the construction of ' Whirlwind,' a 'real-time computer,' taking twice the space of ENIAC, which could constantly monitor its inputs, making it suitable for simulations. In the course of its development, Forrester devised 'magnetic-core memory.' Whirlwind's success caused the U. S. Air Force to fund Project Lincoln, which used Whirlwind as the test bed for the air defense system. This system required analog-digital tele-communication and its engineers built a device called a modulator-demodulator, or 'modem.'
In 1951, Willard Van Orman Quine, in "Two Dogmas of Empiricism," said the distinction between 'analytic' and 'synthetic,' roughly that between ideas and fact, and 'reductionism,' which holds that logical constructs are meaningful if they refer to immediate experience, are each ill-founded dogmas. The real "unit of empirical significance is the whole of science" (Quine 1953:42).
In 1952, Alan Lloyd Hodgkin and Andrew Fielding Huxley, using microelectrodes applied to the gigantic axon of a squid, demonstrated the ionic workings of nerve impulses and described them in a series of mathematical formulas (Hodgkin and Huxley 1952). [revised 02/01/03]
In 1952, Alexander R. Stokes worked out the mathematics of helical diffraction, important in interpreting X-ray crystallographs.
In 1952, Lederbergs and Luca Cavelli-Sforza and William Hayes, working independently, announced that bacteria differentiated into genetic donors and recipients. Hayes said further that when the doner passed a copy of its genes to the recipient, it could also pass the genetic ability to be a donor (J. Lederberg et al. 1952; Hayes 1952).
In 1952, Alexander L Dounce said that the order of amino acids in each specific protein derives from the order of nucleotides in the corresponding RNA molecules which were templated by the DNA molecules (Dounce 1952).
In 1952, Guido Pontocorvo assembled evidence that the gene as the minimum unit of heritable physiological function had considerable length along the chromosome. The gene as the minimum unit in which mutations can be induced is much smaller. Therefore, mutations could occur at different points along a single physiological gene (Pontecorvo 1952).
In 1952, Hershey and Martha Chase showed that when a phage particle infects its bacterial host cell, only the DNA from the phage enters the cell and the protein of the phage remains outside. Combining Chargaff's result with that of the Hershey-Chase experiment meant that the repeating elements of Schrödinger's codescript could be identified as the nucleotides carrying adenine, quanine, thymine, or cytosine (Hershey and Chase 1952).
By 1952, Turing had noticed that patterns are formed by the rates at which interacting chemicals diffuse and react. This "theory can, In principle, account for the specification of most (possibly of all) biological patterns, although the mathematical obstacles are often formidable" (Harold 1990:415). The mathematics involves "the [non-linear] bifurcation properties of the solutions of differential equations. Applied mathematicians had been aware for many years that when a parameter of a system passes through a certain critical value there can be a qualitative change in behavior as a previously stable state becomes unstable. The archetypal example, first studied by Euler more than two centuries earlier, is the sudden buckling of a beam when it is overloaded" (Saunders 1992:xiv). This theory accounts for certain organizational features in plants (e.g., the frequency of five petals and the scarcity of seven petals), but it is also compatible with physiological genetics (Turing 1952).
In 1952, Humphrey Osmond and John Smythies theorized that schizophrenia was the result of a chemical chain reaction, the cycle of which could only be broken by a retreat from 'reality.' Osmond later coined the term 'psychodelic.'
In 1952, Jay Haley and G. Bateson recognized that the symptoms of schizophrenia are suggestive of an inability to discriminate logical types and described it in terms of a double-bind hypothesis (Bateson 1954).
In 1952, R. S. Mulliken worked out and systemized the quantum mechanics of 'charge transfer.'
In 1952, David Bohm , in "A suggested interpretation of the quantum theory in terms of hidden variables, I and II," extended and completed de Broglie's ideas concerning a unified description of quantum mechanics; that is to say, by making certain assumptions, e.g., that the field was objectively real, and, by hiding certain variables, he gave a plausible account of how to eliminate the indeterminism of having more than one point of view (Bohm 1952:369-396).
In 1952, Gian Carlo Wick, Arthur S. Wightman, and Wigner suggested several 'superselection rules' governing unobservable quantum mechanical states (Wick et al. 1952:103; Wightman 1995:754).
In 1952, Donald Arthur Glaser invented the 'bubble chamber,' a device for detecting ionizing radiation, wherein a liquid gas is kept slightly above its boiling point under sufficient pressure to prevent its boiling.  Just before the ionizing particles are released, the pressure is lowered and the particles become the centers of bubbles.  
In 1952, Urey, in The Planets: Their Origin and Development, argued that the cold, original atmosphere of the Earth must have been composed of the stable molecules of methane, ammonia, water, and hydrogen.
In 1952, Baade showed that the Cepheid period-luminosity relation was in error, thereby increasing the Hubble expansion time constant by a factor of two.
In 1952, Michael George Francis Ventris deciphered so-called 'Linear B,' an extremely archaic form of Greek>, probably written by the South Achaeans in the late second millenium bce.
In 1953, G. Mueller reported finding amino acids in a carbonaceous chondrite, a meteorite, but his finding was discounted because of the possibility of contamination.
In 1953, William Maurice Ewing published evidence to support his theory that the sea floors are spreading from central ridges and that the continents consist of plates in motion with respect to each other. This led to the acceptance of Wegener's continental drift hypothesis. With Bruce Heezen, Ewing invented the seismograph which is now standard.
In 1953, Sanger, using dinitrophenol which binds to one end of an amino acid, determined the sequence of the glycyl chain of the amino acid bases in bovine insulin, the first protein to be so analyzed (Sanger and Thompson 1953). The other chain was sequenced by 1955 and revealed that there was a sequence unique to bovine insulin, that it was not a repetitive series, and, in hind site, confirmed that a code would be required for protein synthesis. [added 02/01/03]
In 1953, George E. Palade, Keith Roberts Porter, and Albert Claude developed methods of fixation and thin sectioning that enabled many intracellular structures, which they named 'endoplasmic reticulum,' to be seen in electron microscopes (Porter 1953). [added 02/01/03]
In 1953, Lwoff postulated that the protein coats on viruses are carcinogenic when activated by outside factors such as ultraviolet light (Lwoff 1953; Judson 1978:375). [added 02/01/03]
In 1953, James Dewey Watson and Francis Harry Compton Crick built a model of DNA showing that the structure was two paired, complementary strands, helical and anti-parallel, associated by secondary, noncovalent bonds. This discovery made apparent the mechanism of replication. Their effort brought together the functional and the structural approaches to the study of life: Watson's background was with the phage group and Crick was a physicist learning X-ray crystallography (Watson and Crick 1953). The two approaches combined to become, as Crick called it in 1947, "the chemical physics of biology" (quoted in Judson 1979:110) and, finally, molecular biology. Maurice H. F. Wilkens' and Rosalind Franklin's X-ray crystallographs of DNA supported the discovery of the structure (Wilkens et al. 1953; FranklIn and Gosling 1953).
[In 1953, in working out the structure of the double helix, Watson and Crick had "for the first time introduced genetic reasoning into structural determination by demanding that the evidently highly regular structure of DNA must be able to accomodate the informational element" (Stent 1980:xvii). In other words, "the basis of heredity switched from one based on location to one based on information encoded in the structure of macromolecules" (Sapp 1987:193). Watson and Crick employed 'information,' the recently popularized cybernetic term, differently than cyberneticists: Genetic information is functional whereas cybernetic information is defined as the mathematical converse of entropy].
In 1953, Szilard and Aaron Novick proposed that a cell's synthesis of some enzymes was not stimulated by the presence of an inducer, but by the absence of the enzyme's end product, a classic example of feedback control (Novick and Szilard 1954).
In 1953, Gamow began the attempts to explain the coding problem, that is, how the sequential structure of DNA could directly, physically order the sequential structure of proteins. In Gamow's scheme, several different base sequences could code for one amino acid (Gamow 1954).
In 1953, Konrad Emil Bloch and, independently, Feodor Lynen discovered the mechanics and regulation of cholesterol and fatty acid metabolism: Acetic acid, or acetyl coenzyme A, is converted to mevalonic acid, which is converted to isoprene, a hydrocarbon, which converts into a symmetrical C30 hydrocarbon, squalene. This is converted into lanosterol, and finally into cholesterol (Bloch and Langdon 1957). [revised 02/01/03]
In 1953, G. C. Willis noticed that atherosclerotic plaques keep forming in the same places on the ground substance of the arterial intima and, subsequently, did studies which implicated mechanical stresses, such as high blood pressure and heart beats. That the lesions of scurvy occur in the intimal ground led to Willis's hypothesis that ascorbic acid is a treatment for atherosclerosis (Willis 1953:17-22).
In 1953, Stanley L. Miller, in Urey's lab, bombarded a mixture of ammonia, water vapor, hydrogen, and methane with an electrical discharge to simulate lightening and produced the amino acids alanine and glycine (S. Miller 1953:528-529). "Not since Friedrich Wöhler synthesized urea in 1828 had a chemical experiment been hailed as a comparable milestone" (de Duvé 1991:109-110).  Since that time, a number of experiments have been performed in which these molecules are converted to greater complexity by ultraviolet light and ionizing radiation.
In 1953, Medawar, Leslie Brent, and Rupert E. Billingham established in principle that immunological tolerance could be acquired by injecting hemopoietic cells from a genetically different donor into rodents in utero or at birth. Not having evolved the immunolgical equipment to reject them, the engrafted cells perpetuated themselves, and endowed the recipient with the donor immune system (Billingham et al. 1953).
In 1953 and 1954, Vincent du Vigneaud synthesized the peptide hormones oxytocin and vasopressin.
In 1953, Eugene Aserinsky and Nathaniel Kleitman noticed regularly occurring periods of rapid eye movement (REM) during sleep and correlated this with when dreams are particularly vivid and emotionally charged. This opened a new era of research in the relation of brain to mind.
In 1953, Andrei Sakharov invented a fusion and fission detonator which was the basis for the first thermonuclear bomb built by the Soviet Union. His work was independent of that of Ulam and Teller.
In 1953, Ernst Carl Gerlach Stueckelberg and André Petermann, in "La Normalization des Constantes," reported their discovery of the 'renormalization group,' a group of transformations exploiting the finite arbitrariness arising in scattering-matrix elements after the removal of certain divergences. This theory was first used in quantum electrodynamics: When there occurs an infinite number of parameters, some must be removed, usually by taking the observed mass and charges of the electron as 'renormalized' parameters. Good agreement is obtained with experimental results, despite the apparent impossibility of making the procedure mathematically sound.
In 1953, Iosif S. Shkovskii, arguing that both optical and radio emissions in the Crab Nebulae come from synchrotron radiation, hypothesized that high energy electrons radiate optically visible light whereas lower energy electons radiate at radio wave lengths in the same magnetic field. Because the high energy electrons lose their energy faster, this accounts for the much more intense radio emissions.
In 1953, An Wang invented the magnetic core computer memory.
In 1953, Wittgenstein published his Philosophical Investigations in which he held, among other things, that the mind categorizes on the basis of 'family resemblances:' "How is the concept of a game bounded? What still counts as a game and what no longer does?... We do not know the boundaries because none have been drawn" (WittgensteIn 1953:I, 68-69).
In 1954, Marthe Vogt recognized that noradrenaline was present in the hypothalmus.
In 1954, Rita Levi-Montalcini and associates showed that nerve growth factor stimulated the growth of axons in tissue culture.
In 1954, Paul Zamecnik, working with rat liver, developed and refined the cell-free system, a biochemical cocktail, for protein synthesis. The basic constituents are molecules of RNA containing amino acids, enzymes, ATP, and microsomal particles, or ribozymes.
In 1954, Benzer, working with mutant rII viruses in bacteria, proved that mutations occurred within genes and devised a technique by which one could locate mutations at the scale of a single nucleotide. This enabled him to sequence, or map, the parts of the gene, the amino acids, that is to say, the 200,000 letters of the phage virus genetic code (Benzer 1955).
In 1954, Hugh E. Huxley and Jean Hanson and, independently, A. Huxley and R. Niedergerke observed in X-ray crystallographs that, when muscles contract, the areas built exclusively of actin filaments are comparatively narrow. To explain this, they hypothesized that bridges occur between the actin, or thin, filaments and the thick, or myosin, filaments and that these bridges pull thin filaments past the thick filaments in a racheting action. It is known as the 'sliding filament, moving cross-bridge model.'
In 1954, Anthony C. Allison provided evidence that individuals heterozygous for the sickle-cell gene are protected against malaria.
In 1954, Jean Dausset observed that some recipients of blood transfusions formed antibodies. These antibodies defined the first 'human leukocyte antigens' (HLA) and led to the definition of the 'major histocompatibility complex' (MHC). H-2, an antigen similar to HLA, had been discovered earlier by Snell. HLA can be typed and thus blood tests can determine the compatibility of transplant tissue. MHC is a genetically controlled system by which the body distinquishes material it deems harmful. [revised 02/01/03]
In 1954, Salk developed an injectable killed-virus vaccine against poliomyelytis, the incidence of which began to decline after mass immunization began the following year. [revised 02/01/03]
In 1954, Andrei N. Kolmogorov outlined a theorem, subsequently proved by Vladimir Igorevich Arnold and Jürgen Kurt Moser, and known as KAM theory, which dealt with the influence of Poincaré resonances on trajectories, showed their frequencies to depend on the values of dynamic variables, and provided the starting point for understanding the appearance of chaos in Hamiltonian systems.
In 1954, Chen Ning (Frank) Yang and Richard Mills and others proposed that if there were as many as eight different electromagnetic fields which interacted with each other and with electrons proposed to be of three types of charge, then the charges would be able to change in different places and times. This introduced the idea of non-Abelian gauge fields. A gauge field is a symmetry group. An Abelian group is a symmetry group which commutes, e.g., ab = ba or the aspects of a round ball, whereas non-Abelian groups depend on the direction of rotation for their symmetry, e.g., a book, and are therefore non-communitive.
In 1954, Charles Hard Townes , J. P. Gordon, and H. J. Zieger, in "Molecular microwave oscillator and new hyperfine structures in the microwave spectrum of NH3," developed the theory of the maser, or 'microwave amplification by stimulated emission of radiation.' The maser is an oscillator in which the basic frequency control arises from atomic resonance rather than a resonant electric circuit. The waves are coherent; that is, they're all the same frequency, in the same direction, and the same phase relationship. The following year, Nikolai Gennediyevitch Basov, independently, also developed a maser.
Between 1954 and 1957, Robert Hofstadter used the Mark III Stanford Linear Accelerator and the electron-scattering method, i.e., he bounced electrons off protons or neutrons and measured the recoil angle, to find the size, charge and magnetic moment distribution, and surface thickness parameters of atomic nuclei.
In 1954, Robert Hanbury Brown and Richard Q. Twiss, using a total-intensity interferometer at Jodrell Bank, developed a mathematical theory supporting the idea that basis information from radio telescopes could be gained from correlation after detection.
In 1954, at the time of his death, von Neumann was writing Theory of Self-Reproducing Automata, where he proved, in theory, that a 'cellular automaton' could reproduce itself provided it exceeds a certaIn threshold of complexity. This formalism was suggested to him by Ulam: Each cell in a lattice would be occupied by an automaton in one of a finite number of states. At each tick of a cosmic clock, the automaton would change to a new state, determined by its current state and the states of its neighbors. Automata theory is known as recursion theory among logicians. The book, edited by Burks, was published in 1966.
In 1954, Needham published the seven volumes of Science and Civilization in China.
In 1955, Gold proposed that the Earth's axis sometimes changed by 90 degrees, triggered by movements of its mass.  
In 1955, Walter Sampson Vincent announced experiments which suggested that a small fractional portion of RNA transfers nuclear information to the cytoplasm. This fraction was later given the name transfer RNA, or tRNA. Later that year, Crick hypothesized the existence of an intermediate nuclear product which he called an 'adaptor,' and ultimately came to be recognized as tRNA.
In 1955, Neils Kaj Jerne suggested a natural selection theory of immunity in which cells, while still in the embryo, produce a wide variety of antibodies. Any antibodies which made contact with the embryo's own antigens would be permanently lost. "The early removal of a specific fraction of molecules [would] lead to the permanent disappearance of this type of specificity.... The absent specificities would include, beside auto-antibodies, natural antibody against antigens implanted in the animal during embryonic life" (Jerne 1955:853-854). Later, foreign antigens would select the best fit among the remaining antibodies, bind to them, and be delivered up for dissociation and elimination. The formation of this complex also stimulated the production, i.e., cloning, of more of the selected antibody, which is then capable of a more rapid secondary response.
In 1955, Élie Leo Wollman and François Jacob found that, by agitating a bacterial culture, mating could be stopped when only part of the genes had been piped across, permitting the manipulation of a few genes at a time (Wollman and Jacob 1955).
In 1955, Arthur Pardee and Rose Littman reported that 5-bromouracil, an analogue of the base thymine, causes a high proportion of mutants in phage (Littman and Pardee 1956).
In 1955, Severo Ochoa and Marianne Grunberg-Manago isolated the first enzyme involved in the synthesis of a nucleic acid, an RNA-like molecule in a cell-free system (Grunberg-Manago and Ochoa 1955).
In 1955, Christian René de Duvé and colleagues, using a centrifuge, isolated a new subcellular particle, which they named lysosome to emphasize the hydrolytic, or water-releasing, properties of its enzymes.Lysosomes play a pivotal role in cellular and metabolic processes (de Duvé 1963). Subsequently de Duvé discovered another organelle which he called a peroxisome. Peroxisomes use oxygen to digest or neutralize certain types of molecules (de Duvé 1969).[revised 02/01/03]
In 1955, after Oliver Smithies used starch gels to separate the alleles of inherited protein variations by electrophoresis. Only then were extensive studies of wild species possible.
In 1955, Leo Hurvich and Dorethea Jameson formulated the opponent-process color theory: There are three color 'channels' in the visual system, one channel is achromatic and signals differences in brightness; the other two are chromatic and signal differences in hue. Also, in the retina there are three mosaics of cone cells, the so-called long-wave (L), the middle-wave (M), and the short-wave (S) receptors. The difference between the the signals from the L and M receptors generates the red-green channel, and the difference between the sum of the signals from the L and M receptors and the signals from the S receptors generates the blue-yellow channel (Jameson and Hurvich 1955).
In 1955, Kazuhiko Nishijima and, independently, Murray Gell-Mann identified V particles as an additive quantum number, isospin +1, which Gell-Mann called 'strangeness.'
In 1955, Nicolai Nicolaevich Bogoliubov and Dmitrij V. Shirkov, "using the group properties of finite Dyson transformations for coupling constants and field functions,...obtained group functional equations for QED propagators and vertices in the general (i.e., massive) case," and introduced the term 'renormalization group' (Shirkov 1997:255).
In 1955, Segrè discovered 'anti-protons.'
In 1955, Wheeler described a hypothetical object, a 'geon,' constructed out of electromagnetic radiation varying in size from the smallest field to an entire universe, but "most easily visualized as a standing electromagnetic wave, or beam of light, bent into a closed toroid," and so massive that it will hold itself together by its own gravity (Wheeler 1955:133). "Such an object, viewed from a distance, produces the same gravitational attraction as any 'real' mass, moves in an orbit of its own, and manifests inertia. However, examined in detail..., it proves to contain nothing but empty space" (Wheeler 1962a:57); i.e., a geon "provides a completely geometric model for mass" (Wheeler 1962b:xii).
In 1956, Waddington in Principles of Embryology, defined epigenetics in the broadest possible sense as those interactions of genes with their environment that bring the phenotype into being and demonstrated with Drosophila that selection for the ability to acquire a trait that appears in response to an environmental stimulus may, if it is selectively advantageous, become genetically assimilated after a certain number of generations (Waddington 1957) .
In 1956, Heinz Fraenkel-Conrat and Gerhard Schramm, independently, demonstrated that tobacco-mosaic virus RNA is self-replicating and alone gives the disease.
In 1956, Wollman and F. Jacob published a first, rudimentary genetic map of the E. coli chromosome, and established that when the donor's chromosome entered the recipient, the recipient became endowed with two sets of genes for several hours until resuming cell division.
In 1956, Vernon M. Ingram, using electrophoresis and chromatography, showed that human normal and sickle-cell hemoglobins have different 'fingerprints,' i.e., their amino acids differed due to a mutated gene (Ingram 1958).
In 1956, Paul Berg noticed that the enzyme specific to an amino acid required something more to permit the enzyme to recycle and determined it was (Berg 1956). At about the same time, Zamecnik, Mahlon Hoagland, Robert William Holley, and others made the same determination (Hoagland et al. 1957; Holley 1957). Berg led the way to the enumeration of separate enzymes and species of tRNA for all twenty amino acids (Berg and Ofengand 1958). Zamecnik's lab discovered that tRNA carried, at one end, the three nucleotide sequence cytosine-cytosine-adenine where the amino acid hooked on (Hecht et al. 1958). [revised 02/01/03]
IIn 1956, Arthur Kornberg discovered DNA polymerase, the first of a group of three enzymes responsible for DNA synthesis, that is, the attachment of nucleotides onto the unzipped DNA molecule during DNA replication, and, of the three, the one which repairs damaged DNA. It is the enzyme now used to make DNA probes (Kornberg 1956). [added 02/01/03]
In 1956, Elliot Volkin and Lazarus Astrachan published data which suggested that cells possess a high-turnover RNA, which later proved to be messenger RNA (mRNA)(Volkin and Astrachan 1956).
In 1956, Christian Boehmer Anfinsen, by breaking the various bonds connecting a whole protein, concluded that its three-dimensional conformation is dictated by its amino acid sequence. [revised 02/01/03]
In 1956, Jo Hin Tjio and Albert Levan determined that the human genome has 23 chromosomes.
In 1956, Al Hubbard developed the rule in the therapeutic use of LSD-25 that it was contingent on the mindset of the person taking the drug and the setting in which the experience occurred.
In 1956, Steven Szara synthesized dimethyltryptamine, or DMT, which is closely related to serotonin and best known for its psychotropic properties.
In 1956, Tsung Dao Lee and Yang published the suggestion that the law of parity conservation, or space-reflection symmetry, is violated by the 'weak' force, one of the four fundamental forces. Chien-Shiung Wu and a team led by Ernest Ambler then performed an experiment which showed that parity is not conserved in beta decay, and thus there can be physically lawful asymmetry, or preferred handedness. A team led by Leon Max Lederman and Richard Garvin confirmed this result. A team led by Valentine Telegdi, on the basis of the Lee-Yang paper and without knowledge of the Wu-Ambler results, also showed that parity is not conserved in beta decay (Crease and Mann 1986:208-209).
In 1956, Clyde Cowan and Frederick Reines confirmed the existence of the neutrino.
In 1956, Leon Cooper showed that in superconductivity the current is carried in bound pairs of electrons, or 'Cooper pairs.'
In 1956, Hans E. Suess and Urey provided detailed data on the abundance of elements and isotopes.(Suess and Urey 1956:53-74)
In 1956, Beno Gutenberg and Charles Richter pointed out that earthquake tremors follow a power law: In any given area in a year, the number of earthquakes that release a certain amount of energy is inversely proportional to that energy.
In 1956, G. Miller, dealing with conscious perception and short-term memory in the context of information theory, published "The Magical Number Seven, plus or minus Two: Some Limits on Our Capacity for Processing Information." In it, he measured the 'amount of information' by equating it with ' variance:' "Anything that increases the variance also increases the amount of information" (G. Miller 1956:81).
In 1956, Herbert A. Simon, Allen Newell,and J. Clifford Shaw demonstrated 'Logic Theorist,' their complex information, i.e., not standard algorithmic, but rather 'heuristic procedure,' at a conference on 'artificial intelligence,' or 'AI,' a term invented by John McCarthy (Waldrop 2001:133-139).
In 1956, Wesley Clark, Ken Olsen, and Harlan Anderson finished a transistor-driven interactive computer, the TX-0, the ancestor of the Digital Equipment Corporation's, or DEC's, TX-2.
In 1956, Nathaniel Rochester and John H. Holland published computer programs which simulated neural networks.
In 1957, Matthew Meselson and Franklin Stahl developed density-gradient centrifugation for separating nucleic acids in order to confirm that DNA reproduces itself in the manner predicted by the Watson-Crick model (Meselson et al. 1958).
In 1957, Melvin Calvin, in The Path of Carbon in Photosynthesis, reported his observation of unpaired electron spins, i.e., free radicals, induced by light in photosynthetic systems. The carbon cycle is also known as the Calvin cycle and was determined by using a tracer isotope of carbon-14 in combination with paper chromatography. [revised 02/01/03]
In Earl Wilbur Sutherland isolated cyclic adenosine 5'-monophosphate, or cAMP and explained how it is released through the binding of a hormone to the outside of a cell membrane and goes on to perform many roles in the cell's metabolism (Sutherland 1966). [revised 02/01/03]
In 1957, David W. Talmadge modified Jerne's hypothesis, giving it a cellular orientation, so that lymphocytes, that is, receptor-carrying cells, rather than serum, served as the source of immunological memory and selection (Talmadge 1957). Independently, Burnet seems to have arrived at the same revision. The essence of this theory is fourfold: Each clone is produced somatically by genetic hypermutation; each clone produces antibodies which have the ability to react immunologically with a very small number of chemical configurations on the surface of an antigen; the immune system is able to distinguish self from non-self; and self-tolerance is set up early in life by the elimination of self-reactive lymphocytes (Burnet 1957). [revised 02/01/03]
In 1957, Feynman and Murray Gell-Mann proposed a law tying together the weak interactions at work in strange-particle decay and in beta decay which were permitted by the previous year's Lee-Yang-Wu proof. When a particle decays by a weak interaction, e.g., neutron into proton or pion into muon, one sort of wave is transformed into another sort. The possible transformations include scalar, vector, axial vector, pseudoscalar, and tensor, or S, V, A, P, and T; Feynman and Gell-Mann identified V and A as the wave transformations produced by weak interactions. Robert Marshak and E. C. George Sudarshan drew similar conclusions at about the same time (Gleick 1992:335-338; Johnson 1999:151-153).
In 1957, Bardeen, Cooper, and John Schreiffer formulated the 'BCS theory' of superconductivity according to which a pair of negatively-charged electrons moving through a positively-charged elastic crystal lattice as a result of Coulomb forces.
In 1957, Herbert Kroemer showed theoretically that heterostructural transistors, made by laying down thin layers of semiconductors such as gallium arsenide, should be superior to conventional transitors built from specially modified pieces of a single material such as silicon.
In 1957, Charles W. Misner, while evaluating Feyman's quantization of General Relativity, proved that "the Hamiltonian operator is zero" (Misner 1957:497).
In 1957, Misner and Wheeler proposed that gravity is not a force but rather a manifestation of geometry, i.e., that the entities of geometry are a kind of physical reality. According to quantum 'geometrodynamics,' space is multiply connected by 'wormholes' at the smallest Planck-length distances and therefore has a foamlike structure (Misner and Wheeler 1957:225-307).
In 1957, Hugh Everett, III, proposed a "pure wave mechanics" formulation of quantum mechanics in which the "unique relative-state" of the universe, a closed system, should be taken as coinciding with reality (Everett 1957:454). Reality is taken to be a composite system in which the state vector has many branches and "all possible [measurements] are realized every time, each in a different edition of the universe, which is therefore continually multiplying.... There is no association of the particular present with any particular past (Bell 1981:133). Each automaton, i.e., apparatus cum memory sequence, in each superposed 'branch' sees the world obey the familiar quantum laws, while this 'branching' corresponds to the collapse of the wave function. Memories and records are in fact present phenomena" (ibid.:135-136). If this "theory were correct..., we could safely assume that all possible arrangements of matter and energy are represented somewhere among the infinite ensemble of universes.  Only in a minute proportion of the total would things be arranged so precisely that living organisms, hence observers, arise....  In short, our universe is remarkable because we have selected it by our own existence" (Davies and Brown 1986:38).  Everett considered his theory a metatheory to quantum mechanics. John Stuart Bell considered "the really novel element" to be Everett's repudiation of the 'past,' on a par with Einstein's repudiation of absolute simultaneity (ibid.:118). This has come to be known as the 'many worlds interpretation,' where each instant is a different world.
In 1957, Rudolf L. Mössbauer discovered that when the emitting nucleus of a gamma-ray photon is "held by strong forces in the lattice of a solid, the recoil energy is shared by all the nuclei in the lattice [and] typically...the recoil will be negligible" (Dictionary of Physics 2000:309).
In 1957, E. Margaret Burbidge, Geoffrey R. Burbidge, William A. Fowler, and Hoyle, in "Synthesis of Elements in Stars," or "B2FH," said that "in order to explain all the features of the [element] abundance curve, at least eight different types of synthesizing processes are demanded" (Burbidge et al. 1957:551): Hydrogen burning, responsible for most energy production; helium burning, responsible for carbon synthesis and other syntheses with the capture of additional alpha particles; alpha process, where various elements are synthesized by the addition of alpha particles to Ne20; e, or equilibrium, process, where under very high temperature and density the elements comprising the iron peak are synthesized; s, or slow, process, where neutron capture with the emission of gamma radiation takes place on a long-time scale; r, or rapid, process, where neutron captures occur quickly compared to beta decay; p process, where proton capture is responsible for the synthesis of proton-rich isotopes; and x process, or various processes, responsible for the synthesis of deuterium, lithium, beryllium, and boron, all unstable at the temperatures of stellar interiors. At the same time, Alastair G. W. Cameron, independently, discussed many of the same topics and argued that many of these elements are formed during fast reactions of supernova explosions.
About 1957, Martin Kruskal developed "a coordinate system in which the structure of a black-hole could be described in one smooth set of equations, joining the flat spacetime far outside the hole on to the highly curved spacetime inside without even a hint of a singularity at the Schwarzschild horizon" (Gribbin 1995:129). Wormholes, which topologists call 'handles,' are continuous lines of force that exit and re-enter the observer's world.
In 1957, Kees Boeke, in Cosmic View: The Universe in Forty Jumps, a book intended for children, illustrated what one would see by adding a zero, or power, to the scale of a square picture of two people on a picnic blanket, moving in and out twenty times.
In 1957, the United States government formed the Advanced Research Agency, or ARPA, in response to the Soviet Union's Sputnik, the first artificial satellite.
In 1957, John Backus led the team which created 'Fortran,' the Formula Translation language for the IBM 704 computer.
In 1957, Noam Chomsky, in Syntactic Structures, attacked behaviorism and proved that linquistic grammars are analogous to Turing machines and that both are hierarchical: word strings below phrase structures below transformations between sentence structures.
In 1958, R. J. Goldacre, in "Surface films, their collapse on compression, the shapes and sizes of cells and the origin of life," proposed the possibility that amphipathic lipo-protein films at the air-water interface of the 'primal soup' under the stress of waves formed membrane tubes and then collapsed forming permeable bags "bearing many resemblances to the properties of the membranes of living cells" (Goldacre 1958:287-288).  
By 1958, David L. Nanney, working with ciliated protozoa, Tetrahymena, recognized the existence of two systems: genes and epigenetic mechanisms which regulate 'gene expression,'.
In 1958, Albert H. Coons , coupling antibodies to fluorescent dyes, showed experimentally that one cell made only one antibody (Coons 1958). Later that year, Gustave J. V. Nossal and Lederberg, working together in Burnet's lab, verified the clonal selection theory's requirement that there could only be one antibody type produced by any given lymphocyte; this came to be known as 'allelic exclusion' (Nossal and Lederberg 1958). The same year, Lederberg recognized that, in the context of random drift, it was necessary to postulate the continuation throughout life of the diversification of antibody-producing cells. Lederberg also postulated that two signals initiated by a single interaction but separated in time were necessary to distinguish between inactivation of self and activation of nonself. Further, he introduced the rhetorical dichotomy between the terms selective and instructive, representing respectively the clonal and template models (Lederberg 1959). Until Jerne's theory, all immunologists were agreed that the antigen impressed its mark on, or instructed, the antibody producing cells. [revised 02/01/03]
In 1958, Crick enunciated the legendary 'Central Dogma': "Once information has passes into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible" (Crick 1958:153). [added 02/01/03]
In 1958, Stein and Moore invented the automatic fraction collector and contibuted to the development of the automated amino acid analyzer. [added 02/01/03]
In 1958, F. Jacob and Wollman named and described 'episomes,' which are "circular, extrachromosomal sequences of DNA that possess the capacity to integrate into, as well as dissociate from, the chromosome of a cell. They can replicate either autonomously or while inserted within the chromosome" (Podolsky and Tauber 1997:392n24; Jacob and Wollman 1958).
In 1958, Hofman isolated the active ingredient of the mushroom Psilocybe and synthesized psilocybin, which he noted had a marked similarity to serotonin.
In 1958, Phillip W. Anderson showed that the effect in a metal of strong 'disorder,' or irregularity, perhaps arising from a high concentration of atomic impurities, would localize all the electron wave functions; i.e., each quantum state would be confined to a certain region, falling off exponentially with the distance outside that region.
In 1958, Townes and Arthur L. Schawlow published their idea for an optical mazur, or 'laser.' Gordon Gould, independently, developed a similar idea.
In 1958, Jack St. Clair Kilby built the first integrated circuit.
In 1958, Ryle and colleagues found the first real evidence that the Universe is evolving. By counting the numbers of galaxies of different apparent intensities, "the number of [weak] sources was found to be about twice that expected from counts of intense sources [and thus] there appears to be a real discrepancy between the observations and the predictions of the steady-state model" (Ryle 1958:306). "This [is] compatible with an evolving Universe if galaxies were more prone to undergo violent outbursts in the remote past, when they were young" (Rees 1995:5-6).
In 1958, Cornell H. Mayer and colleagues reported the surface of Venus is around 600 degrees K.
In 1958, Eugene N. Parker proposed the 'solar wind' theory: There is a flow of atomic particles from the Sun's corona, following from hydrodynamic equations of a million degree corona, which carries with it magnetic field lines that form into a spiral pattern as the Sun rotates.
In 1958, Michael Polanyi, in Personal Knowledge, asserted that there is an interpretative ingredient in scientific knowledge.
In 1958, Heisenberg, in Physics and Philosophy, wrote: "If actually all our knowledge is derived from perception, there is no meaning in the statement that the things 'really exist;' because if we have perceptions of things it cannot possibly make any difference whether the things exist or do not exist. Therefore, to be perceived is identical with to be existing" (Heisenberg 1958:84).
In 1958, Herbert Gelernter devised 'Geometry Theorem Prover' In Fortran List Processing Language.
In 1958, a joint United States and European committee, including among its members, Backus, Alan Perlis, and McCarthy, was formed to create a universal programming language, 'Algorithmic Language,' or 'Algol.' In the course of creating Algol, Backus and Peter Naur invented 'Backus-Naur notation' for giving the formal definition of a programming language. Although little used after its completion in 1960, Algol was the precursor of 'Pascal.'
In 1959, R. H. Whittaker added a fifth domain, fungi, to the taxonomy of living things (Whittaker 1959).
In 1959, Noel L. Warner and Aleksander Szenberg performed the experiments which led to the concept of T (for thymus) cells and B (for bursa In birds, but produced in the bone marrow of adult mammals) cells (Szenberg and Warner 1962).
In 1959, Pardee, F. Jacob, and Monod published an experiment establishing a generalized model of the synthesis of enzymes. That this occurs in the absence of genetically determined repressors is due to exogamous induction; that is, the immunity of lysogenic cells corresponds exactly to inductibility and, if regulation occurs at the gene and not later in the process, then regulation is completed at the level of the ribosome (Pardee et al. 1959).
In 1959, Edmond H. Fischer and Edwin Gerhard Krebs isolated and purified the first protein kinase and described 'reversible protein phosphorylation.' Protein kinase takes phosphate from adenosine triphosphate and adds it to phosphorylase, turning it on. Another enzyme, protein phosphatase, reverses this process, deactivating the phosphorylase (E. G. Krebs et al. 1959). [revised 02/01/03]
In 1959, Porter showed that the antibody molecule could be cut into three pieces by utilizing an enzyme which cuts bonds within the peptide chain. Of the three pieces, two would still combine with antigen. These he named antigen-binding fragment, or Fab, and the third piece, crystallizable fragment, or Fc. The Fc region corresponds to different types of effector function. Also, he showed that the whole antibody could be divided into different functional classes, i.e., IgA, IgD, etc (Porter 1959).
In 1959, Gerald M. Edelman demonstrated, by using reducing agents to split sulphide bonds between the peptide chains, that the immunoglobulin gamma G, or IgG, molecule, the most prevalent class in mammals, was a multi-chaIn structure. This showed that the chains were a reasonable size for determination of their amino acid sequence. Edelman also showed that antibodies are constructed in a modular fashion from domains, with the light chain composed of a variable and a constant domain and the heavy chain composed of four domains, three variable and one constant. Furthermore, he showed that the variable domains share homologous regions as do the constant domains (Edelman 1959).
By 1959, Stein and Moore determined the amino acid sequence of pancreatic ribonuclease (RNase) which breaks down RNA so that its components can be reused. This was the first enzyme to have its function and structure to be completely described and confirmed that the amino acid sequence is a three-dimensional, chain-like structure which folds and bends in causing a catalytic reaction (Stein and Moore 1961). [added 02/01/03]
In 1959, Bengt Ingemar Samuelsson and Sune K. Bergström isolated prostaglandins. Samuelsson deduced the process by which arachidonic acid is converted into endoperoxides and that into prostaglandins.
In 1959, Albert Bruce Sabin developed a oral, live-virus vaccine against poliomyelitus.
In 1959, H. Sherwood Lawrence proposed that infectious agents complex with transplantation antigens (self + x) and triggered lymphocytes to produce a soluble, specific receptor for this complex (Lawrence 1959).
In 1959, Konstantin Gringauz, employing Soviet Luniks Satellites, observed the first signs of the solar wind.
In 1959, Luna III, a Soviet satellite, photographed the far side of the moon.
In 1959, James A. Van Allen, Carl E. McIlwain, and George H. Ludwig, in "Radiation Observations with Satellite 1958e," established the existence of geometrically trapped electrons and protons in a belt 2000 km from the surface of the Earth. The following year, Van Allen arranged for a rocket with a particle detector aboard which found another radiation belt higher above the Earth. Today, these are known as the inner and outer Van Allen belts.
In 1959, George B. Field, Frank D. Drake, and S. Hvatum suggested that the planet Jupiter's radio emission is caused by synchrotron radiation of magnetically trapped electrons.
In 1959, Robert Noyce devised a way to "mass-produce integrated circuits by etching thousands of transistors simultaneously onto the surface of a single silicon wafer" (Waldrop 2001:339).
In 1959, students in Rochester's and McCarthy's computer programming class at the Massachusett Institute of Technology called elaborate switching networks for model railroads 'hacks,' and, tranferring the usage to programming, the designers of elaborate software solutions 'hackers.' (Waldrop 2001:187).
In 1960, Sidney W. Fox converted amino acids into polymer proteinoid microspheres by heating them.  They showed a wide variety of catalytic ability, albeit extremely weakly (Fox 1965:361-373).  
In 1960, Crick, Sydney Brenner, and F. Jacob predicted the existence of messenger RNA, the substance that gets repressed. The latter two and Meselson soon isolated it (Brenner et al. 1961).
In 1960, F. Jacob, David Perrin, Carmen Sanchez, and Monod developed the 'operon model,' which showed that "the discovery of regulator and operator genes, and of repressive regulation of the activity of structural genes, reveal that the genome contains...a coordinated program of protein synthesis and the means of controlling its execution" (Jacob and Monod 1961:354). The rate of information transfer from genes to proteins could be controlled by oscillation, that is, turned 'on' and 'off' at a specific speed. The exogamous inducer was almost invariably the end-product so this model did much to popularize the notion of feedback among molecular biologists (Jacob et al. 1960).
In 1960, Jerne introduced the terms 'epitope' and 'paratope' to represent antigenic determinants and antibody-combining sites, respectively (Jerne 1960:342).
In 1960, Julius Marmur and Paul Doty reported that denatured, that is, unfolded, polypeptides could be renatured, regaining their original structure, provided that the two single strands were perfectly complementary (Doty et al. 1960).
In 1960, Max Perutz and John Kendrew worked out the crystallographic structure of the oxygen-carrying proteins, hemoglobin and myoglobin, a labor that Perutz had begun 23 years previously (Perutz 1960; Kendrew 1960).
In 1960, Juan Oró, using concentrated solutions of ammonium cyanide in water, produced the nucleotide adenine. [added 02/01/03]
In 1960, Yoichiro Nambu and Giovanni Jona-Lasinio constructed a quantum field model in which the pion is a composite of fermion and anti-fermion of small, but non-zero, mass. This mass is obtained through the spontaneous breaking of chiral symmetry.
In 1960, Wheeler showed that "a completely geometric model [could be constructed] for electricity, as lines of force trapped in the topology of a multiply connected manifold" (Wheeler 1962b:xii). He also said that elementary particles "represent a first-order correction to vacuum physics [which is the physics of zero-point energy at absolute 0 degrees]. That vacuum, that zero-order state of affairs, with its enormous densities of virtual photons and virtual positive-negative pairs and virtual wormholes, has to be properly described before one has a fundamental starting point for a proper perturbation-theoretic analysis" (Wheeler 1960:129). Perturbation theory may be applied to the study of the orbits of planets, in classical physics, or to calculate the energy level of molecules, in quantum mechanics.
In 1960, Theodore H. Maiman described the first laser, which used a synthetic ruby rod as the lasing medium.
In 1960, Allan R. Sandage and Thomas A. Matthews isolated optically an intense radio source, 3C-48, which, a couple of years later, turned out to be a 'quasar.'
In 1960, Eugene Merle Shoemaker proved that an asteroid created the 1.2-mile diameter crater near Flagstaff, AR, and theorized that the moon's craters had a similar origin. This was confirmed by Apollo 17 in 1972.
In 1960, McCarthy invented a new language for AI, 'List Processor,' or 'Lisp,' in which every list defined a recursive mathematical function, e.g., plus, which could then be nested inside other functions, e.g., (times (plus 2 2)(minus 5 3)) becomes (times 4 2) becomes 8.
In 1960, Joseph Carl Robnett 'Lick' Licklider, in "Man-Computer Symbiosis," pictured "a network of [online 'thinking'] centers, connected to one another by wide-band communications lines and to individual users by leased-wire services" (Licklider, quoted in Waldrop 2001:177).
In 1960, Quine suggested a strategy for discussing disparate conceptual schemes by a 'semantic ascent,' arguing that "words, or their inscriptions, unlike points, miles, classes, and the rest, are tangible objects of the size so popular in the marketplace, where men of unlike conceptual schemes communicate at their best" (Quine 1960:272); i.e., don't talk about things, talk about the way we talk about things.

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