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1986-01-01
Research on silicon dioxide has developed in several distinct, nearly independent patterns. The electronic band structure of crystalline SiO_2 is well established, and progress is being made on amorphous SiO_2. Thus the transport of electrons and holes may be understood and mechanisms for defect creation by ionizing ra...
Electronic Properties of SiO_2 and Models for its Point Defects
null
1986-01-01
The main emphasis in this chapter is on two types of magnetic systems: on the percolation problem which corresponds to a zero-temperature dilute quenched ferro-magnet; and on the spin glass problem, where the interactions between nearest-neighbor Ising spins can be both ferromagnetic and antiferromagnetic. In both prob...
Monte Carlo Studies of Systems with Disorder
null
1986-01-01
Ce chapitre traite de la théorie du glissement double dans le domaine de l’écoulement des matériaux avec frottement. Cette théorie avait été formulée par Mandel (1947) et ensuite développée par Spencer (1964). Nous la réexaminons dans le contexte des théories de glissement relatives à la plasticité des métaux, et en pa...
Generalization of the Mandel—Spencer Double-slip Model
null
1986-01-01
Attaining an understanding of the mechanisms controlling the aging process has proven to be a uniquely difficult biological problem. Many hypotheses have been advanced offering explanations for the phenomenon of senescence at a variety of different operational levels, ranging from the molecular to the evolutionary. Ind...
Genetics of Aging: Effective Selection for Increased Longevity in Drosophila
null
1986-01-01
This song cycle has an exceptionally strong and immediate appeal to the widest possible variety of listener. Despite its length, it never fails to hold the attention, largely because the words are set so that they can be heard with complete clarity and never fail to make their full impact. The audience can thus easily ...
Evening Land (1981)
null
1986-01-01
This skilful and attractive work is written in a continuous span but it contains many contrasting sections and can either be considered as a cycle or a short cantata. The voice is used in the most imaginative and colourful way and the singer’s tone must be light and flexible enough to move speedily. The staccato passag...
A Vision of Time and Eternity op. 61 (1972)
null
1985-12-01
For zero and intermediate applied external fields, the dynamics of the static spin polarization associated with muons which have thermalized in the allowed stopping sites of a given solid is expressed in terms of counter and crystal frame spherical harmonic tensor expansions of the second-rank dynamical motion tensor. ...
On the observables associated with zero and intermediate applied external field muon spin rotation
null
1985-12-01
A quantum mechanical solution to the problem of stimulated emission in axial and flat magnetic undulators, including electron spin properties, is presented.
Stimulated emission by relativistic electrons in magnetic undulators
null
1985-12-01
Yearly population fluctuations of M. pustulae were investigated at 19 sites in Kyushu. In sites where a platygastrid is the only parasitoid of the midge, the percentage parasitism was very low in the incipient stage of the outbreak of the midge populations. After the number of midges reached a peak, the midge populatio...
Population regulation of the euonymus gall midgeMasakimyia pustulae Yukawa andSunose (Diptera: Cecidomyiidae) by hymenopterous parasitoids
null
1985-12-01
A spin label study has been carried out on bipolar lipids extracted from Sulfolobus solfataricus , an extreme thermophilic archaebacterium growing at about 85°C and pH 3. These lipids are cyclic diisopranyl tetraether molecules, quite different from the usual fatty acid lipids. Two hydrolytic fractions of the membrane ...
A spin label ESR and saturation transfer-ESR study of archaebacteria bipolar lipids
null
1985-11-01
A comparative study of crystalline and amorphous DyAg using^161Dy Mössbauer spectroscopy is presented as a way to gain insight into the changes in electronic structure and spin dynamical properties of the rare-earth ion when its local surrounding is randomly distorted. It can be seen, especially in the paramagnetic reg...
Electron structure and spin dynamical properties of crystalline and amorphous rare-earth intermetallics from Mössbauer and μSR experiments
null
1985-11-01
The method of μSR is briefly described and its potential in the field of solidstate physics (especially metal physics) is discussed. Some examples from the fields of magnetism, spin relaxation and particle diffusion in metals are shown and comparisons with conventional hyperfine interaction methods are made for some ar...
Some examples from muon spin rotation
null
1985-11-01
Heavy-ion reactions using pulsed beams have had a strong impact on the study of hyperfine interactions. Unique advantages offered by this technique have considerably extended the scope, detail and systematic range of its applications beyond that possible with radioactivity or light-ion reactions. This survey will cover...
Hyperfine interaction studies with pulsed heavy-ion beams
null
1985-09-01
In this paper the ‘class of near homoaxial rotations’ is defined, being suitable for treatment of problems of nonuniform rotation of stars. This class is represented by a proper form of the so-called ‘velocity tensor’, the latter describing efficiently the motion of a deformable finite material continuum in the common ...
Rotational dynamics of celestial bodies
null
1985-09-01
Dynamics of spin systems in rapidly oscillating external fields
null
1985-09-01
Although a number of theories of law stress the importance of examining the characteristics of deviance processing agents for understanding criminal sanctioning, empirical studies have generally neglected these variables. Using data from a sample of convicted felons, this study looks at (1) both the additive and intera...
Legal outcomes and legal agents
null
1985-09-01
A review of the maximum longevity of bivalves and gastropods indicates that a greater than average number of life spans coincide with the periods of long-term cycles in marine communities. Apparently, long-term cycles exert an important influence on marine communities by affecting the life spans of constituent species....
Are molluscan maximum life spans determined by long-term cycles in benthic communities?
null
1985-08-01
We analyse recent ESR measurements on Ca^2+ ATPase and Myelin proteolipid apoprotein reconstituted in phosphatidylcholine bilayer membranes. Our intention is to discover whether the measurements indicate significant protein-protein repulsive or attractive interactions. In order to do so we have studied a model of a lip...
Protein lateral distribution in lipid bilayer membranes
null
1985-07-01
Bounded flow sound a supercavitating wing of finite span
null
1985-07-01
Particles with variable spin and a composite hadron model
null
1985-07-01
Realization of the Poincaré group as a subgroup of GL (5, R ) that maps an affine set into itself is shown to lead to a well-defined minimal replacement operator when the Poincaré group is allowed to act locally. The minimal replacement operator is obtained by direct application of the Yang-Mills procedure without the ...
Direct gauging of the Poincaré group
null
1985-04-01
A theoretical study of the effects of multipulsed NMR on the angular distribution of radiations from oriented nuclei is reported. The perturbation factors of the angular correlation function may be written in general form for any scheme of multipulsed excitation of a nuclear spin system. The irreversible relaxation is ...
On the theory of multipulsed excitation of spin-echo and free-induction decay signals in angular distribution of oriented nuclei radiation
null
1985-04-01
The ambiguity in the application of the principle of dynamic scaling to spin waves in dilute ferromagnets is resolved by taking account of the fractal nature of the infinite percolation cluster.
Dynamical scaling for spin waves in dilute ferromagnets
null
1985-04-01
Formally exact equations are written down, describing the translational and rotational diffusion of an anisotropic tagged particle in a fluid of anisotropic particles. These equations are tractable in the long-time limit, and reduce to the solution of ordinary hydrodynamic equations supplemented by slip boundary condit...
Translational and rotational diffusion of an anisotropic particle in a molecular liquid: Long-time tails and Brownian limit
null
1985-03-01
Recruitment, life span and growth rate were investigated in field and experimental populations of Abra alba (Wood) in Kiel Bay, FRG (55°N) from 1975 to 1978 to determine production to biomass ( P:B ) ratios and to assess the importance of A. alba to production by commercial fish. Life span and growth rates were determi...
Population dynamics and production of the bivalve Abra alba and implications for fisheries production
null
1985-02-01
A model has been developed for 5-nitroxide stearate, I(12,3), distribution in human erythrocyte ghosts which accurately predicts ESR spectral alterations observed with increased probe/total lipid (P/L) at 37°C. This spin probe occupies a class of high-affinity, noninteracting sites at low loading. Saturation occurs wit...
Spin probe clustering in human erythrocyte ghosts
null
1985-01-01
In this review we show that Electron Spin Resonance (ESR) can be used to investigate the time scale and specificity of lipid-lipid and lipid—protein contacts in membranes. Details are given of the simulation of the spectra obtained with labeled lipids either covalently attached to the boundary of rhodopsin or freely di...
Simulation of the Electron Spin Resonance Spectra of Spin-Labeled Fatty Acids in Protein-Containing Model Membranes
null
1985-01-01
Describing a scene or object can be done at several different levels. Lower levels involve chiefly local features or attributes while at higher levels one tends to focus on relations between parts of the object. It is a major concern of today’s cognitive sciences and artificial intelligence to devise frameworks for the...
Dynamics of the Central Nervous System
null
1985-01-01
Saturation kinetics of inhomogeneous resonance lines has been investigated in very dilute ruby samples at T=4.2°K by the saturation transient technique. Experimental evidence of the effectiveness of intraline spectral diffusion is reported. Satisfactory agreement is found between the experimental results and a theoreti...
The Effect of Spectral Diffusion on the Saturation Transient Regime
null
1985-01-01
Spin glasses are disordered magnetic materials with unusual magnetic properties. The complicated structure of the phase space, especially the existence of infinitely many metastable states, leads to long time relaxational processes. Important experiments and models are briefly outlined. Analytical and numerical results...
Spin Glasses as Model Systems for Neural Networks
null
1985-01-01
Even the most general conception of the protein molecule — which is imagined as a homopolymer with a linear memory — necessarily involves its capability of fluctuation (Lifshits, 1968; Lifshits and Grosberg, 1973). Statistical analysis indicates that the homopolymeric coil executes continuous macroscopic pulsations, an...
Conformational Mobility of Proteins
null
1985-01-01
A short review of disorder induced effects in magnetic media is presented. Novel concepts essential to non-collinear magnetic structures and their dynamics are briefly discussed and illustrated by experimental examples.
Magnetic Order in Disordered Media
null
1985-01-01
Conventional electron spin resonance (ESR) spectroscopy of nitroxide radicals is sensitive to motions corresponding to correlation times in the range 10^−11–10^−7 sec. If the motion is anisotropic, with a fast component in the 10^−9–10^−11 sec. range, an order parameter can be measured; the latter is indicative of the ...
Conventional ESR Spectroscopy of Membrane Proteins: Recent Applications
null
1985-01-01
The spin rate distributions of comet nuclei and small asteroids are compared, and it is shown that Whipple’s (1982) finding of a faster average rotation for the asteroid sample was due to observational biases. In fact, the presently available rotational data do not exhibit any clear differentiation among comet nuclei a...
On the Rotation of Cometary Nuclei and Small Asteroids
null
1985-01-01
The ρ meson spin alignment is studied in $$ \bar pp $$ interactions at 22.4 GeV/c and in the reaction $$ \bar pp \to 2\pi ^ + 2\pi ^ - $$ + neutrals at 5.7 GeV/c. An essential ρ^O meson spin alignment is observed. The values of the ρ^T _OO element of the meson spin density matrix in the transversity frame are equal to ...
Polarisation Effect of ρ Produced in $$ \bar pp $$ Interactions at 5.7, 12 and 22.4 GeV/c
null
1985-01-01
A statistical treatment is used to calculate the correlation functions and the spectral densities for the secular and nonsecular parts of the dipolar relaxation processes when molecular diffusion is bounded to finite two-dimensional planar surfaces. This leads to convergent formulas for spin-spin T _2 ^-1 and spin-latt...
Theory of Spin Relaxation by Translational Diffusion in Two-Dimensional Systems
null
1985-01-01
In our discussion of the applications of the dynamic model as a description of the properties of biopolymers and their hydrate shells, we have not so far dealt with their functional significance. We shall now attempt to apply the fundamental assumptions which underlie the dynamic model of behavior of proteins in water ...
Dynamic Model of Association and Dissociation of Specific Complexes
null
1985-01-01
In this paper we review recent experimental results and ideas about pressure effects on the behaviour of proteins and lipids. The approach will be physico-chemical. The interested reader is referred to other papers presented in this volume (see also Paton et al.,1984) for the biological background to these studies. For...
Pressure Effects on Phospholipids and Proteins
null
1985-01-01
The concept that biomembranes are built on a lipid bilayer matrix is now commonly accepted. Suggestions have been made that non-lamellar regions may also occur within the structure of natural biomembranes^l, although this view is presently somewhat controversial^2,3. The proteins associated with biomembranes are locate...
The Interaction of Intrinsic Proteins and Lipids in Biomembranes
null
1985-01-01
On the Ising spin glass I. Mean field
null
1985-01-01
Magnetic Resonance Imaging (MRI) allows the display of anatomical heart structures at a temporal resolution in the magnitude of 20 ms. Several pictures may be taken in one scanning process or with consecutive measurements at varying trigger delay times. By comparison of the positions of certain myocardial regions at ce...
Principles for the Study of Heart Dynamics with Magnetic Resonance Imaging
null
1985-01-01
When we try to understand living organisms, biological membranes present a problem of considerable interest. Over the years it has become clear that these lamellar structures not only form boundaries between different subcellular environments but that they also fulfill many other functions of great importance, both obv...
Physical Methods on Biological Membranes and Their Model Systems: A Perspective
null
1985-01-01
The use of nuclear spin relaxation measurements in the study of liquid crystal dynamics goes back only to 1969, to work by Doane (1), Blinc (2), Cabane (3) and their coworkers. Practically all of the early work relied upon proton relaxation measurements (4,5), and several major mechanisms and relaxation pathways were i...
Nuclear Spin Relaxation
null
1985-01-01
The concentration dependences of dipolar homogeneous broadenigs and cross-relaxation rates in condensed media are analyzed by means of effective reduced distributions. Elimination of interacting species due to either clustering or recombination processes, which do not participate to the processes under study, leads to ...
Concentration Dependences of Homogeneous Broadenings and Cross-Relaxation Rates in Condensed Media: The Role of Pair Distributions
null
1985-01-01
In a liquid crystal phase several kinds of motion take place simultaneously, some of them occurring essentially at the molecular level (rotations, translations, conformational changes) some others involving large numbers of molecules (collective order fluctuations). These last motions are typical of the liquid crystall...
Diffusive and Collective Motions in Liquid Crystal Phases
null
1985-01-01
The detection in absorption lines of gas clouds outside the galactic plane at high velocities by Münch and Zirin (1961), high velocities then defined as velocities differing by more than 20 km/s from the LSR, showed that the space outside the Milky-Way disk contains not just stars. Of course, from a continuity argument...
The Milky Way: A Halo, a Corona, or Both?
null
1985-01-01
The dynamics of the Heisenberg ferromagnetic spin chain is of fundamental importance in soliton theory, as it is a typical model system which is completely integrable under suitable circumstances and is endowed with interesting geometrical aspects [1,2]. In particular, the one-dimensional continuum limit of the classic...
On the Nonlinear Excitations in One-Dimensional Uniaxial Anisotropic Heisenberg Ferromagnetic Spin Chain in External Magnetic Fields
null
1985-01-01
Some results from measurements of multibody photoproduction at medium incident photon energy (2.8 to 4.8 GeV) are presented and discussed. Particular emphasis is placed on topics which are not well understood and which therefore motivate experiments with the upgraded electron accelerator and storage ring ELSA at the Un...
Hadron photoproduction at medium energy
null
1985-01-01
An enigma facing investigators who seek to explain the pathogenesis of ethanol-induced diseases is the wide variety of tissues and organs affected by this compound. Moreover, the effects of acute and chronic ethanol intoxication are not only different, but often of an opposite nature. Whereas acute ethanol intoxication...
Ethanol and Biological Membranes: Experimental Studies and Theoretical Considerations
null
1985-01-01
The interaction of poly(vinyl acetate) with modified aluminum surfaces has been investigated using the spin label technique to monitor motion at the polymer-metal interface as a function of temperature, coating thickness and exposure to water. The modified aluminum surfaces used for adhesive bonding, designated CAA and...
Surface Modified Aluminum-Poly (Vinyl Acetate) Interaction in the Presence of Water
null
1985-01-01
On the Ising spin glass II. Fluctuations
null
1985-01-01
In quantum mechanics, a physical observable is described by a (linear) operator Q on a Hilbert space H and a (pure) state is described by a unit vector Ψ in H. The expectation value (the average of measured values for a large number of repeated measurements) of the observable Q in the State Ψ is given by 1.1.1 <m:math ...
Dynamic and Ergodic Properties of the XY-Model
null
1985-01-01
Exchange scattering can be separated from direct scattering processes by using polarized electrons and/or atoms and observing the polarization of the scattered electrons or of the recoil atoms. The mechanism underlying the polarization effects is discussed.
Polarization Effects Caused by Exchange Processes in Electron-Atom Scattering
null
1985-01-01
The special pair model for the primary donor of bacterial photosynthesis which was originally proposed on the basis of EPR spectroscopy [1] has now been confirmed by x-ray structural data [2]. The initial interpretation of the EPR linewidth of the donor cation was based on a symmetrical sharing of the unpaired electron...
Triplet State Investigation of Charge Separation and Symmetry in Single Crystals of R. viridis Reaction Centers
null
1985-01-01
We have studied the ^93Nb NMR in single crystals of (NbSe_4)_10/3I (1.8 mg) and (NbSe_4)_3I (20 mg). In the first compound, the onset of the CDW has been followed through the temperature dependence of the (1/2,−1/2) transition. Using computer simulation of the lineshapes, we have determined the temperature dependence o...
^93Nb NMR study of CDW in (NbSe_4)_10/3I single crystal
null
1985-01-01
The functional model of enzymatic activity which will be presented is really a development of the association and dissociation mechanisms of specific complexes, such as the mechanism described in the preceding chapter. Käiväräinen (1979c) derived expressions interconnecting the rate of enzymatic reaction and the Michae...
Dynamic Model of Protein Behavior and Mechanism of Enzymatic Function
null
1985-01-01
The development of Dirac Phenomenology is reviewed. The systematic features of the model are compared with the relativistic treatments of nuclear reactions and nuclear structure. The standard Lorentz scalar - Lorentz vector Dirac optical potentials are used in the analysis of proton, neutron and anti-proton scattering....
A review of phenomenological Dirac analyses
null
1985-01-01
The fluidity of a fluid is the reciprocal of its viscosity which in turn is a measure of the resistance of the fluid to movement within it ^1, 2. The unit of viscosity is the Poise (P) and, measured by the motion of various physical probes, membranes at ambient temperatures seem to be far more viscous or far less fluid...
Membrane Fluidity and Lipid Composition
null
1985-01-01
We shall now consider, from the aspect of the dynamic model of behavior of proteins in water, the effect on proteins of agents which, when present in small doses, perturb the system protein+water as one whole without, however, impairing its native properties. We shall assume, for the sake of simplicity, that all the pr...
Effect of Perturbing Agents on the Dynamic Properties of Proteins
null
1985-01-01
It has been known for many years that the membranes of living cells can flow. Hydrodynamic flow of a biological membrane in the liquid crystal state can be expected, and its quantitative analysis is the province of fluid dynamics. In this chapter we will be mainly concerned with rather different kinds of motion that ha...
Motion
null
1985-01-01
New vistas of the shapes and structures of nuclei far off stability
null
1985-01-01
A new Graphic Differential (GD) suggested by French (1977) may be used as a language-free alternative to the Semantic Differential (Osgood, Suci, & Tannenbaum, 1957). The new GD (which is based on prior attempts by other writers) consists of 5 pictographic scales for each semantic dimension: Evaluation, Potency, and Ac...
A cross-cultural investigation of the graphic differential
null
1985-01-01
There are few molecules that are not either adsorbed onto or dissolved in lipid bilayers, and the literature is replete with studies on contaminated phospholipids. In natural membranes the main “impurities” are proteins, glycoproteins, and cholesterol. In this chapter we look at the way in which such molecules perturb ...
Proteins, Cholesterol, and the Lipid Bilayer
null
1985-01-01
Field-cycling and conventional proton relaxation spectroscopy in the frequency range 10^4 ≤ v ≤ 3·10^8 Hz have been applied to diverse lyophilized and D_2O-hydrated globular proteins and poly-L-alanine. An overall T _1-dispersion T _1 ∼ v ^0.75±0.05 has been found.This v ^3/4-law is tentatively interpreted by a double-...
Double-diffuisve fluctuations and the v ^3/4-law of proton spin-lattice relaxation in biopolymers
null
1985-01-01
The model studies presented here seek to probe possible effects that the protein environment may induce or impose on the conformation and electronic configuration of photo-synthetic chromophores. Results are presented for the effect (or lack of it) of axial ligation and hydrogen bonding on the electron spin resonance (...
Experimental, Structural and Theoretical Models of Bacteriochlorophylls a, d and g
null
1985-01-01
A large number of different measurements which are sensitive to gap states in hydrogenated amorphous silicon have been analyzed over the past few years in an attempt to determine the generic form of the density of states function within the mobility gap of this material. These results tend to support one or the other o...
Is the DLTS Density of States for Amorphous Silicon Correct?
null
1985-01-01
Although it is generally the case that thermodynamic concepts can be derived from detailed statistical mechanical considerations (and not vice versa) and therefore statistical mechanics is more general than thermodynamics, one can still learn a lot from thermodynamics. As one example, standard manipulations of partial ...
Introduction and Guide to This Text
null
1985-01-01
C*-algebras are known to provide a proper mathematical framework for quantum Statistical mechanics of spin systems on an infinitely extended lattice in the same way as Hilbert spaces for quantum mechanics. In the present article, we try to show that theory of C*-algebras is useful not only for a general formulation but...
C*-Algebra Approach to Ground States of the XY-Model
null
1985-01-01
Interaction of domain wall with a spin wave in the framework of an integrable case of the Landau-Lifshitz equations
null
1985-01-01
Since membranes are constructed of molecules and belief in vital forces is unfashionable, it can be safely assumed that the forces within membranes are no different from the familiar electrostatic and van der Waals forces used to account for the properties of all molecular ensembles. If this is so, the devotion of a co...
Forces
null
1984-12-01
The reproductive patterns of two different age classes of Leptocarabus kumagaii adults, i.e. young beetles which were in the first year of adult stage and old ones which survived for more than two years, were studied in the field. The numbers of eggs laid were compared between young and old females and the effects of f...
Long adult life spain and polyphagy of a carabid beetle,Leptocarabus kumagaii in relation to reproduction and survival
null
1984-11-01
We show that both charmonium and upsilon spectra can be simultaneously fitted by an effective non-coulombic power-law potential with lowest order relativistic corrections. The fine-hyperfine splittings of these spectra can be well understood without considering the short distance coulombic part of the potential as sugg...
Charmonium and upsilon systems with fine-hyperfine splittings
null
1984-10-01
Coherent neutron scattering lengths and total cross sections were measured on elemental Ga, Ga-compounds and on isotopically enriched samples at neutron energies from 0.5 meV up to 143 keV using different techniques. From the experimental data the following quantities could be obtained: the coherent scattering length o...
Interactions of neutrons with gallium and its isotopes
null
1984-10-01
The spin hydrodynamic equations for superfluid^3He-B have been obtained for the case of external, time-dependent fields. On the basis of a microscopic approach, expressions are found for additional terms in equations containing these fields. Considering the linear response of the system to the switching on of external ...
Spin hydrodynamic equations with external disturbances and suitable Green's functions for superfluid^3He-B. New onsager relations
null
1984-09-01
Ferromagnetic spin chains with planar single ion anisotropy, exchange anisotropy and with an external field b applied in the easy plane are considered in classical continuum approximation. It is pointed out that in the static case the sine-Gordon approximation is only accidentally exact: it breaks down in the neighborh...
Planar ferromagnets: Low-velocity kink dynamics near to the easy plane and static solitary spin structures bifurcating from the azimuthal kink
null
1984-09-01
The regeneration process of a subalpine coniferous forest, a mixed forest of Tsuga diversifolia (dominant species), Abies veitchii, Abies mariessi , and Picea jezoensis var. hondoensis , was studied on the basis of annual ring data. The age class distribution was discontinuous and four age groups occurred in the study ...
Regeneration in subalpine coniferous forests
null
1984-09-01
The reactions K ^− p → π ^∓ Σ (1385)^± are studied at an incident laboratory momentum of 8.25 GeV/c using data from a high statistics (≃180 events/μb) bubble chamber experiment. In the case of the reaction K ^− p → π ^− Σ (1385)^+ an amplitude analysis is performed and the complete Σ(1385)^+ spin density matrix is extr...
The reactionsK ^− p→π ^∓ Σ(1385)^± at 8.25 GeV/c
null
1984-09-01
We review evidence that biological aging is a genetic process related to development and cytodifferentiation and thus may involve alterations of DNA structure and gene expression. We conclude that although determined to a high degree aging also involves stochastic features which lead to progressive somatic cell diversi...
Genetic modifications during cellular aging
null
1984-04-01
Lines homozygous for the Adh ^S and Adh ^F alleles were extracted from a French and an African natural population of D. melanogaster . The lines from each geographic region were then crossed and the Mendelian F_2 constituted the first generation subjected to selection for an increase in adult survival in the presence o...
Extension of life duration by dietary ethanol in Drosophila melanogaster: response to selection in two strains of different origins
null
1984-03-01
A new approach to quaternions and to one-index spinors in the Euclidean three-space is offered, directly derived from the vector formulation of the Euler's theorem on the general displacement of a rigid body with a fixed point. A linear and injective correspondence between quaternions and one-index spinors is introduce...
Development of spinor descriptions of rotational mechanics from Euler's rigid body displacement theorem
null
1984-03-01
Recent developments in the theory of spin glasses are discussed. There has been considerable progress, due to Parisi, Sompolinsky, and others, towards understanding the infinite range (mean field) model of Sherrington and Kirkpatrick. Relaxation times diverge in the thermodynamic limit, and this nonergodic behavior is ...
Spin glasses
null
1984-03-01
Free radical and radical ion intermediates in the photochemical reactions of carbonyl compounds with organometals
null
1984-02-01
Among the various models proposed so far to account for the properties of neural networks, the one devised by Little and the one derived by Hopfield prove to be the most interesting because they allow the use of statistical mechanics techniques. The link between tween the Hopfield model and the statistical mechanics is...
Collective properties of neural networks: A statistical physics approach
null
1984-02-01
Electron spin resonance (ESR) studies of human erythrocyte ghosts labeled with 5-nitroxide stearate, I(12,3), indicate that a temperature-dependent lipid phase separation occurs with a high onset at 38°C. Cooling below 38°C induces I(12,3) clustering. Similar phase separations were previously identified in human platel...
Thermotropic lipid phase separations in human erythrocyte ghosts and cholesterol-enriched rat liver plasma membranes
null
1984-02-01
Spectral and relaxation characteristics of the HMBA Cr^V complex for polarized nuclear targets have been performed. Long time stability of the HMBA Cr^V complex in I.2 propylene glycol solution is investigated. Spin-lattice relaxation time and spectral diffusion rate versus concentration have been obtained.
Spectral and relaxation-time measurements in the HMBA Cr^V radical at 150 GHz
null
1984-01-01
We outline some of the theoretical tools that are now available for studying rare-gas solids (RGS) in which low concentrations of atoms or molecules have been embedded. Our main emphasis is on the changes in the lattice dynamics of the host RGS caused by the presence of such impurities and the dynamics of the atoms and...
Dynamics of Impure Rare-Gas Crystals
null
1984-01-01
Let us now draw some conclusions for the two-dimensional Ising model with short range random interactions and a relaxational dynamics: - The model describes experiments qualitatively - It has no static transition - Nevertheless in the field H, temperature T and observation time t diagram, Fig. 6, there is a rather well...
Static and dynamic properties of short range Ising spin glasses
null
1984-01-01
Muon spin relaxation ( μ SR) and neutron spin echo (NSE) measurements of magnetic ion correlation times and correlation functions in the spin glass systems Cu Mn, Ag Mn, and Au Fe are compared. It is found that the μ SR and NSE measurements are in excellent agreement both above and below the spin-glass freezing tempera...
Spin-glass dynamics determined from muon spin relaxation and neutron spin echo measurements
null
1984-01-01
In this paper the results obtained by using TEMPOL, TM-TEMPAMINE^+, Octanoyl-, Dodecanoyl-, and Hexadecanoyl -TEMPO as spin labels for micellar solutions of C_8—SO_4 Na, C_12-SO_4Na and C_16-SO_4Na are reported. The analysis of ESR lineshape, of reorientational correlation time, τ, and hyperfine coupling constant, <A_N...
ESR Study of Spin Labels in Surfactant Micelles
null
1984-01-01
When normal lymphocytes are incubated in tissue culture medium with certain substances, they are stimulated to differentiate into blast cells which may then proliferate. This process of activation in vitro can be induced by at least five different types of agents: (1) specific antigens which may stimulate lymphocytes f...
Glycosphingolipid Domain Formation and Lymphocyte Activation
null
1984-01-01
In recent years biomembrane fluidity has become the object of intense research.* Fluidity is fundamentally linked to membrane structure. For an elucidation of structure-related questions, such as drug action, membrane transport, and enzymatic activities, a variety of biophysical methods have been acquired. Referring to...
Fluidity of Cell Membranes in the Presence of Some Drugs and Inhibitors
null
1984-01-01
We show that a straightforward generalization of Wigner theorem, or of Dirac's superposition principle, allows to introduce deterministic frictional forces in quantum dynamics. These dissipative evolutions are fully compatible with the Hilbert space structure of quantum kinematics, and provide a description of damped q...
A model of irreversible deterministic quantum dynamics
null
1984-01-01
First-row transition metal complexes with d^4 up to d^7 electron configuration in octahedral ligand fields (and d^8 electron configuration in six-coordinate complexes of lower symmetry) may undergo temperature dependent high spin (HS) ⇌ low spin (LS) transition, provided the ligand field strength (Δ), including low sym...
Spin Transition in Iron Compounds
null
1984-01-01
Exact nonlinear differential equations are developed for large motions of articulated rigid body systems such as mechanisms, vehicles, robots etc.. Parameters entering the equations are, among other quantities, the number of bodies, the number and location of joints interconnecting the bodies and the kinematical charac...
Analytical Methods in Mechanical System Dynamics
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1984-01-01
The field ( H ) dependence of the muon longitudinal spin-lattice relaxation rate well below the spin glass temperature in Ag Mn is found to obey an algebraic form given by ( H )^ v −1 with v =0.54±0.05. This suggests that Mn spin correlations decay with time as t ^− v , in agreement with mean field theories of spin-gla...
Muon spin relaxation measurements of spin-correlation decay in spin-glassAgMn
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1984-01-01
The measurement of polarized fluorescence from a fluorescent ATP or ADP analog, ɛ-ATP or ɛ-ADP (1, N^8 -Etheno-ATP or ADP) bound to myosin heads in a glycerinated muscle fiber revealed that during isometric contraction at low concentrations of Mg-ɛ-ATP the bound nucleotides are highly oriented with respect to the fiber...
Angles of Fluorescently Labelled Myosin Heads and Actin Monomers in Contracting and Rigor Stained Muscle Fiber
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1984-01-01
Muon spin rotation (µSR) has been used to probe the dynamics of rare-earth ions in situations where the crystal field splittings have important effects. This paper outlines the theory of spin dynamics in such cases and discusses its application to µSR studies in two specific systems: erbium in noble metals and holmium ...
Spin Dynamics of Rare Earth Ions in Crystal Fields Probed by Muon Spin Rotation
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1984-01-01
The effects of the charge exchange process on muon spin dynamics have been investigated using a density operator formalism with special interest placed upon the diamagnetic muon and paramagnetic muonium signals observed after thermalization. In the charge exchange region the dynamics of the spin density operator is ass...
Charge exchange of muons in gases: Experimental implications from rate theory
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1984-01-01
The purpose of this talk is to discuss some results obtained from the Monte Carlo (M.C.) simulation of the combined production and decay process e^+e^−→τ^+τ^− (γ), τ→υ e(μ, π, ρ …) based on the O(α^3) QED calculations, including Z_0 exchange (in the low energy approximation). The effects due to finite mass of τ, and to...
Monte Carlo Simulation of the Process e^+e^−→τ^+τ^− (γ)^+
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1984-01-01
Phase transitions (PT’s) are announced dynamically, by a critical slowing-down phenomenon which manifests itself in general by “softening” of a normal-mode frequency. Thus, bulk PT’s both in lattice dynamics and in magnetism are associated with an extended soft mode (soft phonon and soft magnon, respectively), announci...
Dynamics of Phase Transitions in Ferromagnetic Domain-Wall Structures
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