Showing papers in "Biophysical Journal in 1965"

TL;DR: The assumptions of the model are relaxed and the effects of such experimentally found phenomena as relative refractory and supernormal periods, adaptation, potentiation, and rhythmic slow potentials are discussed.

TL;DR: The theory is compared with all the available crystallographic data on simple (di- and tri-) peptides, cyclic peptide, polypeptide and protein structures, and the observed data fully support the conclusions from theory.

TL;DR: The x-ray and ultraviolet responses for component stages of the cell cycle were respectively compounded into expected survival data for a log phase asynchronous population of hamster cells and found to agree well with direct experiment.

TL;DR: A theoretical analysis of the voltage-current relationship is carried out in a membrane consisting of two fixed charge regions, of opposite sign, in contact and it is shown that the system displays the property of rectification and is very similar in many respects to a solid state P-N junction diode.

TL;DR: It is found that most biological cells may be treated as dielectric particles whose capacitive effects are negligible and the current pulse may be made conductivity-independent when observed with a zero input impedance amplifier.

TL;DR: Calculations are reported of the time-dependent Nernst-Planck equations for a thin permeable membrane between electrolytic solutions for charge neutrality and boundary effects that occur when charge neutrality does not hold in the steady-state case.

TL;DR: Ultraviolet light action spectra in the range 2250 to 3020 A have been determined for the plaque-forming ability of the following bacteriophage and animal viruses: T-2, varphix-174, R-17, fr, MS2, 7-S, fd, vesicular stomatitis, vaccinia, encephalomyocarditis, reovirus-3, and polyoma.

TL;DR: In this paper, a possible correlation between certain amino acids in the sequence and the location of the helical and non-helical parts of the structure is suggested, based on the known sequences and structures of myoglobin, and alpha and beta hemoglobin.

TL;DR: New statistical techniques are employed to further analyze the flight control system of grasshoppers and confirm some hypotheses which arise from previous studies of this system.

TL;DR: Detailed observations of the tail movement of non-rotating and rotating bull spermatozoa have been carried out and model calculations indicate that the stiffness of thetail originates in the fibrous sheath, which has a Young's modulus of 3 x 10 dynes/cm(2).

TL;DR: The data provide the first evidence for two distinct types of photoreactivation of cell killing, one of which appears not to involve photoenzymes, and photoprotection results from intracellular events that can be induced by treatment after, as well as before, far ultraviolet irradiation.

TL;DR: An attempt is made to repeat, under standard conditions and with as much care as possible, five of the more definitive types of experiments previously performed on the biological transport system of monosaccharides in human erythrocytes.

TL;DR: The respiratory system exhibits the properties of a control system of the regulator type and equations describing this biological control system have been derived and further extensions of the model are suggested.

TL;DR: It is found that the average frequency inside the sections of Poisson shower remains unchanged in all cases examined, and a mathematical model is developed which characterises the signal of any one neurone with a number of simple parameters.

TL;DR: Interspike interval histograms of spontaneous and stimulated activity were computed from spike discharges of single units in the cochlear nucleus and indicate that a number of different types of spontaneous discharge patterns exist in the nucleus.

TL;DR: Effective conductivities are reported for the bacteria Escherichia coli and Micrococcus lysodeikticus over a range of environmental conductivity and the model points to the usefulness of dielectric techniques in studies of the properties of intact cell walls.

TL;DR: An asymmetry in the quadrupole splitting observed in hemoglobin is attributed to a directional dependence of the recoil-free fraction which establishes the sign of the electric field gradient in the molecule and indicates that the lowest lying d orbital of the Fe atoms is |xy>.

TL;DR: The results show that for a step change in solution composition the observable potential across a membrane having fixed, but not necessarily uniformly spaced, sites becomes independent of time once equilibria are established at the boundaries of the membrane and attains its steady-state value even while the ionic concentration profiles and the electric potential profile within the membrane are changing with time.

TL;DR: A probabilistic method of analysis of spike trains is presented which provides a complete statistical description of spike sequences and allows the elucidation of some of the properties of the neural interconnections producing the output patterns.

TL;DR: The chromatographic detection and isolation of DNA-RNA hybrids on columns of methylated albumin coated on kieselguhr (MAK) is described, which is uniquely effective in experiments involving hybridization with small DNA fragments.

TL;DR: The properties of the steady states of a system composed of two solutions separated by a quite general type of ion exchange membrane having fixed sites are derived as functions of the compositions of the solutions and of the difference of electric potential between the two solutions.

TL;DR: The constancy of the Moffitt optical rotatory dispersion parameters for polypeptides in differentsolvents was tested by dispersion measurements on poly-gamma-benzyl-L-glutamate in fifty-five solvents and solvent mixtures and variation in b(0) can be interpreted as an effect of solvent polarizability on the frequencies of optically active transitions.

TL;DR: It was found that the birefringence of aqueous solutions of sodium DNA is anomalous when electric fields of high intensity (>/=10(4) v/cm) are applied), and it is proposed that the electric field may cause aggregation of the macromolecules and then produce a structural transition concomitant with theElectric field orientation effect.

TL;DR: The Moffitt b(0) parameter of poly-L-glutamic acid in the presumed helical state varied with solvent composition, ranging in magnitude from less than 600 degrees in aqueous solution to 800 degrees in methanol, demonstrating uncertainty in the helical content of proteins and polypeptides determined by rotatory dispersion measurements.

TL;DR: The only model that is self-consistent and agrees with all of the experimental facts is the one based on the concept that the entire living cell represents a proteinaceous fixed-charge system; this model correctly predicts all four types of interaction observed.

TL;DR: A formula is derived which extends the solid angle potential formulation for an active cell in a volume conductor to the case of unequal internal and external conductivities.

TL;DR: The segregation of label among progeny isolated by micromanipulation from such starved cells supports the view that the chromosomes are brought to a state of completed synthesis with different cell classes containing different integral numbers of chromosomes.

TL;DR: It is shown that fluctuations introduce no independent components into the relaxation spectrum when a dissolved macromolecule is in chemical equilibrium with a free ionic species.

TL;DR: The model presented here comprises a feedback loop involving only a proportional control in thyroparathyroidectomized, and a combination of proportional and integral controls in normal animals that accounts for the variations observed when the system was subjected to a variety of experimental constraints.

TL;DR: Equations describing the movement of sugars during induced uphill transport were derived on the assumption of a simple carrier transport mechanism and subjected to experimental verification, finding good agreement between the experimental points and the theoretical curves.