Showing papers in "Journal of Theoretical Biology in 1964"

TL;DR: A genetical mathematical model is described which allows for interactions between relatives on one another's fitness and a quantity is found which incorporates the maximizing property of Darwinian fitness, named “inclusive fitness”.

TL;DR: A number of experimental results are found to be consistent with the possible existence of a physiological inertial system of either a pure or hybrid form, and further investigation of the problems of animal navigation from the standpoint of inertial navigation appears merited.

TL;DR: It is expected that groups in which there is low individual tolerance of suboptimal environment will have high levels of static polymorphism based on epistatic complexes, a high degree of F2 breakdown, and a high rate of speciation.

TL;DR: An attempt to develop logically the basic premises that tissue fractionation is a chemical method to be conducted according to the ground rules which govern chemical fractionation in general.

TL;DR: It is suggested that, in some circumstances, biological membranes may be composed of both kinds of globular subunits, and that this arrangement would provide a means of localizing enzymic and hormonal activity within the plane of the lipid layer of the membrane.

TL;DR: The expressions of the present theory of the ion transport through the cell membrane could be reduced to those of theories presented by several other authors, by introducing appropriate assumptions.

TL;DR: Though, of course, its predictions are sometimes only rough approximations to biological data, the model strikes a useful compromise between accuracy and simplicity, thus providing a convenient means for interrelating existing experiments and suggesting new ones.

TL;DR: A simple model of determination proposed to explain the similar arrangement of abdominal sensory hairs in the bug, Rhodnius prolixus, has been examined quantitatively and found to account satisfactorily for the regular pattern of central primary follicles.

TL;DR: An attempt at a “time-statistical” approach is outlined, in terms of time-averages of certain tracer properties, which results in an ergodic theorem, which gives a general and simple relationship between the tracer and the mother substance.

TL;DR: It is suggested that the water permeability properties of cells are not as diverse as they appear to be when judged by means of their widely different conventional permeability coefficients, which ignore the possible rate-limiting effect of water diffusion in the cell interior.

TL;DR: It is shown that the plaque diameter increases linearly and depends primarily on the squareroot of the diffusion constant divided by the square root of the lag period.

TL;DR: Almost arbitrary combinations of steady state density gradients with gradients of composition, conductivity, pH, etc., can be established in STAFLO experiments without the usual gradient mixing devices.

TL;DR: A model for the photochemical steps in photosynthesis is described in which only one type of reaction center participates in the chemical conversion of excitation energy and the nature of chlorophyll in the two pigment systems is identified on the basis of spectroscopic evidence.

TL;DR: A number of preparative and analytical problems of complex biological mixtures can be advantageously attacked by the stable-flow free boundary (STAFLO) method, and necessary and sufficient conditions for the steady state and for a “normal” flow-pattern configuration are given.

TL;DR: Experimental and theoretical aspects of STAFLO migration, fractionation and concentration are analyzed, particularly with reference to cell mixtures, and an electrophoretic mobility of a dye is estimated from the slope of a steady state STAFLo-electrophoresis migration pattern.

TL;DR: It appears that cellular locomotive pressure is an important quantity in the physical analysis of initial contact between Chaos chaos cells.

TL;DR: A model system for the regulation of enzyme activities is proposed, which belongs to the class of allosteric inhibitions, is not limited to end product inhibition and is complementary to other systems.

TL;DR: It is hypothesized that some of these cells, believed to be small lymphocytes, have a dormant life-span which may last for several years in vivo and that these long-lived small lymphocyte are immunologically ‘committed’ and that they are an important basis of long-term immunity.

TL;DR: A simple method of determining precursor order from data relating input and output to time is presented and the problem of selecting a limit is discussed and related to the general characteristics of models and synthesis of models.

TL;DR: The results suggest that model-systems can be usefully applied to explore the basic mechanisms of enzyme synthesis as well as the effect of various pool concentrations and rate constants on the rate of enzymes synthesis.

TL;DR: It was found that in the case of the G — C base pair one excitation having a large probability, produces changes in the π electron distribution, which makes the G—C→G ∗ —C ∗ simultaneous tautomeric rearrangement more probable thus giving a possible interpretation of the mutagenic effect of ultraviolet radiation.

TL;DR: The dimensions of the α helix are such that certain simple repeats of a small number of amino acids within a helical protein can generate ninefold symmetry, accounting for the pattern of nine seen in electron microscope images of α keratin microfibrils.

TL;DR: The importance of factors influencing both specificity and selectivity of action are critically discussed, and it is suggested that specificity of action only is concerned with adrenergic blocking action, but that both selectivity and specificity are of importance in the design of effective anti-tumor agents.

TL;DR: By further studying the axial and equatorial overlap of the A-protein models, possible explanations for the radial density pattern and axial repeat dimensions of TMV protein have been presented.

TL;DR: This method showed that DNA synthesized during only part of a cycle is considerably more stable, and the constants relating the syntheses of structural RNA and structural ribosomes appeared to be rigidly determined over the range of solutions tested.

TL;DR: The problem of the stability of cellular systems to environmental changes is reviewed with particular reference to bacteria, and a model system, “the biochemical vat” is proposed to study metabolic stability.

TL;DR: From the numerical results obtained it is possible to interpret qualitatively the lowering of the absorption maxima of the single bases from the first transition of the appropriate single bases.

TL;DR: A model of the duplication of a cyclic chromosome in Escherichia coli is presented, which assumes two forms of DNA polymerase, by whose action polynucleotide is elongated in both directions of the chain with definite polarity, and an exact matching of the rates at which these enzymes travel along the two template strands of the mother chromosome.

TL;DR: The theory developed over a number of years by this author is here surveyed in a concise form, there being a sequence of definitions, assumptions and propositions, with connecting and explanatory text.