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International audience; As recently recalled in this journal, Einstein based in 1905 his argument for the existence of quanta on the volume dependence of the black-body entropy in the Wien limit. A similar analysis, starting from the (physically correct) Planck 1900 radiation law, is reputed to be highly complicated. We show that, in contrast, it can be made simple and instructive, if one introduces the notion of volume of coherence. In particular, it gives an additional opportunity to acknowledge the importance of the notion of mode and to discuss the distinguishability of quanta. This paper is intended for physicists interested in the history of quanta and graduate students.

Aim. To investigate the direct relationship between tumour hypoxia and lactate dehydrogenase (Ldh) levels in serum and tumour in two different pre-clinical murine models. Materials and methods. Experiments were performed in CDF1 or C3H/Km mice implanted with a C3H mammary carcinoma and SCCVII squamous cell carcinoma, respectively. Low oxygen breathing for 1-72 h was used to increase tumour hypoxia. Ldh activity was measured in the serum and tumour cytosole with a colorimetric method. Tumour Ldha mRNA levels were assessed with RT-PCR. Results. The serum Ldh in non-tumour bearing CDF1 mice and C3H/km mice was 10.5+/-2 U/ml and 12+/-2 U/ml, respectively. For C3H mammary carcinoma bearing mice, a positive correlation between tumour volume and tumour and serum Ldh was found. Tumour Ldh in SCCVII carcinomas also increased with increasing tumour volume, but no volume dependence of serum Ldh was found. Low oxygen breathing caused a 2-3 fold increase in tumour Ldha mRNA in both tumour models. In C3H mammary carcinoma bearing mice, serum and tumour Ldh significantly increased after 48 and 72 hours of hypoxia, respectively. Low oxygen breathing did not change serum and tumour Ldh in SCCVII carcinoma bearing mice. Reoxygenation for 4 or 24 hours had no additional effect on Ldh activity in any of the models. Discussion. Serum Ldh activity can be a marker for tumour burden in certain types of cancer. The relationship between serum and tumour Ldh and tumour hypoxia has not been confirmed. However, Ldha mRNA may be a potential new marker of tumour hypoxia and should be further investigated.

The mass and volume dependence of the Mori coefficients and of the self-diffusion coefficient has been studied in a two- dimensional system for a Brownian particle in a (T, p, N) ensemble. The 2D Mori coefficients are affected differently from the 3D results. The 2D self-diffusion coefficient is mass independent as it is also in 1D and 3D when the Brownian particle has the same volume as the solvent particle, but if the volume is changed, the weak mass dependence found in 3D is not present in 2D.

Les deux frequences de reseau non nulles decroissent lineairement avec la temperature. Rien ne confirme le comportement anormal, observe anterieurement, de la compressibilite pres de la raie du melange. Indication par les parametres de Gruneisen d'un mode translationnel de la raie a basse frequence et d'un mode librationnel a haute frequence

In this work, a study of the volume dependence of refractive index and electronic polarizability of MgO, under hydrostatic pressure up to 10 GPa, is presented. The experimental results obtained show a decrease of the refractive index with pressure, and enable the calculation of the change of the polarizability a with volume V. The classical Lorentz-Lorenz approach describes well the results and gives a linear dependence between a and V. The results in the whole pressure range yielded a constant Mueller parameter of 1.28, that is in good agreement with a previous work in the low pressure range.

This work revisits the pentaquark episode, particularly in reference to lattice QCD, to collect in one place the lessons that have been or should be learnt. This also examines whether, and if yes, where, there might be any prospect for future studies of pentaquarks and the role of lattice QCD in it. Tests such as volume dependence, and hybrid boundary conditions to distinguish bound and scattering states are identified as the positives to take forward from this episode. On the other hand it is also observed that pentaquarks with heavier quark content and in the $SU(3)_f$ limit may still be worth not forgetting, and in that case lattice QCD may have an important role to play., 7 pages, 4 figures, presented at Lattice 2007, Regensburg, Germany, 30 July - 4 August 2007

Step instability and surface mass transport strongly influence the kinetics of the two- to three-dimensional (2D-3D) transition in InAs/GaAs self-assembly epitaxy. In this paper we report evidence of the step erosion of quantum dots (QDs) nucleated on step edges for samples having different surface morphologies and the explosive nucleation of 3D QDs triggered by it. Related issues such as the temperature dependence of the critical thickness, the volume dependence of the surface mass transport, and the scaling behaviour are illustrated by means of RHEED and AFM measurements and data analysis for small increments of InAs coverage throughout the 2D-3D transition.

The phase boundary between β-Si3N4 and γ-Si3N4 is investigated at high-pressure and high-temperature using first-principles lattice dynamics calculations within the quasi-harmonic approximation. We find a positive slope of the phase boundary. It turns out that the thermal expansion of the spinel-type γ-phase is larger than that of the phenacite-type β-phase. On the other side, pressure affects more the volume of β-Si3N4 than of γ-Si3N4, reflected in the higher bulk modulus of γ-Si3N4. The origin of the different temperature behavior of these phases, consequently, goes along with a larger volume dependence of the zero point energy in γ-Si3N4 in comparison to β-Si3N4.

Low temperature wavelength-modulated reflectivity measurements of isotopically engineered $\mathrm{ZnO}$ samples have yielded the dependence of their A, B, and C excitonic band gaps on the isotopic masses of Zn and O. The observed dependence is analyzed in terms of the band gap renormalization by zero-point vibrations via electron-phonon interaction and the volume dependence on isotopic mass. A simplified, two-oscillator model, employed in the analysis, yields zero-point renormalizations of the band gaps, $\ensuremath{-}154\ifmmode\pm\else\textpm\fi{}14\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$ (A), $\ensuremath{-}145\ifmmode\pm\else\textpm\fi{}12\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$ (B), and $\ensuremath{-}169\ifmmode\pm\else\textpm\fi{}14\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$ (C), for $\mathrm{ZnO}$ with natural isotopic composition.

The solid solution YbCu5−xAgx maintains the cubic AuBe5 structure for 0.15 ⩽ x ⩽ 1. The variation of the physical properties can be described by a volume change due to the Cu/Ag substitution, which is confirmed additionally from applied external pressure.

We have investigated the structures and the elastic constants of hcp $\mathrm{Mg}{\mathrm{B}}_{2}$ at high pressures using the full-potential linearized muffin-tin orbital (FP-LMTO) scheme within the generalized gradient approximation correction (GGA) in the frame of density functional theory (DFT). The obtained normalized volume dependence of the resulting pressure is in excellent agreement with experiment. The elastic constants and acoustic anisotropy as a function of the applied pressure are presented. An analysis for the calculated parameters has been made to reveal the anisotropy of $\mathrm{Mg}{\mathrm{B}}_{2}$.

Pressure strongly depresses the superconducting transition temperature ${\mathit{T}}_{\mathit{c}}$ of both the doped fullerenes and the \ensuremath{\beta}-ET[(BEDT-TTF${)}_{\mathit{nX}\mathit{m}}$, (BEDT-TTF)=bis(ethylenedithio)tetrathiofulvalene)] organic superconductors. An outstanding puzzle in these materials is the weak variation ${\mathit{dT}}_{\mathit{c}}$/dP across families of compounds with large variations in ${\mathit{T}}_{\mathit{c}}$. This property has been used to argue against phonon-induced pairing. However, closer examination of the volume dependence of ${\mathit{T}}_{\mathit{c}}$ reveals that the weak variation of ${\mathit{dT}}_{\mathit{c}}$/dP is consistent with moderate (but not weak) electron-phonon coupling. \textcopyright{} 1996 The American Physical Society.

Properties of relevance for the equation of state for a high‐density glass are discussed. We review the effects of failure waves, comminuted phase, and compaction on the validity of the Mie‐Gruneisen EOS. The specific heat and the Gruneisen parameter at standard conditions for a ρ0 = 5.085 g/cm3 glass (“Glass A”) is then estimated to be 522 mJ/g/K and 0.1 – 0.3, respectively. The latter value is substantially smaller than the value of 2.1751 given in the SESAME tables for a high‐density glass with ρ0 = 5.46 g/cm3. The present unusual value of the Gruneisen parameter is confirmed from the volume dependence determined from fitting the Mie‐Gruneisen EOS to shock data in Ref. [2].

X-ray-diffraction measurements for fluid mercury up to the supercritical region have been carried out using synchrotron radiation at SPring-8. We obtained the structure factor $S(Q)$ with good signal-to-noise ratio, and the pair distribution functions $g(r)$ for expanded fluid Hg from the liquid to the dense vapor. To see the volume dependence of the local structure in fluid Hg in detail, we tried to reproduce $4\ensuremath{\pi}{n}_{0}{r}^{2}g(r)$ of fluid Hg using Gaussian peaks. The optimized parameters show that the asymmetrical first peak in $g(r)$ of liquid Hg consists of atomic distributions at short and long distances of about $3\mathrm{\AA{}}$ and $3.5\mathrm{\AA{}}.$ Volume dependence of the parameters suggests that decrease of the atoms coordinated at the short distance is strongly correlated with the metal-nonmetal transition in fluid Hg.

After bronchoconstriction, deep inspiration (DI) causes dilatation followed by airway re-narrowing. Re-narrowing may be faster in asthmatic than nonasthmatic subjects. This study investigated the relationship between re-narrowing and the magnitude of both DI-induced dilatation and the volume-dependence of respiratory system resistance ( R rs ) during tidal breathing. In 25 asthmatic and 18 nonasthmatic subjects the forced oscillation technique was used to measure R rs at baseline and after methacholine challenge, during 1 min of tidal breathing, followed by DI to total lung capacity (TLC) and passive return to functional residual capacity (FRC). Dilatation was measured as the decrease in R rs between end tidal inspiration and TLC, re-narrowing as R rs at FRC immediately after DI, as per cent R rs at end-tidal expiration, and volume dependent tidal fluctuation as the difference between mean R rs at end-expiration and end-inspiration. Asthmatic subjects had greater re-narrowing, less dilatation, and greater tidal fluctuations both at baseline and after challenge. Re-narrowing correlated with baseline tidal fluctuation and inversely with dilatation. Both baseline tidal fluctuation and dilatation were significant independent predictors of re-narrowing. Following deep inspiration-induced dilatation, faster airway re-narrowing in asthmatic than nonasthmatic subjects is associated not only with reduced deep inspiration-induced dilatation but also with some property of the airways that is detectable prior to challenge as an increased volume dependence of resistance.

We explore applications of the maximum entropy method (MEM) to determine properties of unstable particles using the four-dimensional O(4) $\phi^4$ theory as a laboratory. The spectral function of the correlation function of the unstable $\sigma$ particle is calculated with MEM, and shown to yield reliable results for both the mass of $\sigma$ and the energy of the two-pion state. Calculations are also made for the case in which $\sigma$ is stable. Distinctive differences in the volume dependence of the $\sigma$ mass and two-pion energy for the stable and unstable cases are analyzed in terms of perturbation theory.

This paper presents the development, testing, and application to experimental data of a new model to: (1) estimate the degree of sequential filling during inhalation, and (2) the dependence of the diffusing capacity (D/sub L/) on alveolar volume (V/sub A/). The model assesses sequential filling through a single parameter, k, where k=0 represents complete alveolar mixing, and k=1 represents no alveolar mixing (sequential filling). A linear (a+bV/sub A/) and an exponential (/spl alpha/V/sub A//sup /spl beta//) dependence of D/sub L/ are used to describe the volume dependence of D/sub L/ for carbon monoxide (CO) and nitric oxide (NO), respectively. Application of the model to experimental data from 7 normal humans predicts k=0.51 (0.35), b=0.69 (0.79), and /spl beta/=0.65 (0.19) (mean(SD)). We conclude: (1) D/sub L/ depends on lung volume (strongly for NO, weakly for CO), and (2) the effect of sequential filling must be considered when estimating D/sub L/.

After a short presentation of KMS states and modular theory as the unifying description of thermalizing systems we propose the absence of transverse vacuum fluctuations in the holographic projections as the mechanism for an area behavior (the transverse area) of localization entropy as opposed to the volume dependence of ordinary heat bath entropy. Thermalization through causal localization is not a property of QM, but results from the omnipresent vacuum polarization in QFT and does not require a Gibbs type ensemble avaraging (coupling to a heat bath)., 10 pages, based on talk given at the 2002 Londrina Winter School

The aim of the GRAL project is to simulate full QCD with standard Wilson fermions at light quark masses on small to medium-sized lattices and to obtain infinite-volume results by extrapolation. In order to establish the functional form of the volume dependence we study systematically the finite-size effects in the light hadron spectrum. We give an update on the status of the GRAL project and show that our simulation data for the light hadron masses depend exponentially on the lattice size., Comment: 3 pages, 1 figure, Lattice2003(spectrum)

This paper reconsiders return-volume dependence for the U.S. and six international equity markets. We contribute to previous work by proposing surprise volume as a new proxy for private information flow and apply extreme value theory in studying dependence for large volume and return, i.e. under situations of market stress. Results from a GARCH-M model indicate that surprise volume is superior in explaining conditional variance and reveals a positive market risk premium. Under conditions of market stress, the return-volume dependence is weaker, albeit mostly significant. The results for the U.S. market are most pronounced in that surprise volume explains ARCH- as well as leverage- effects and, under market stress, the return-volume dependence remains significant and symmetric. For the European and Asian markets, however, the dependence is weaker with asymmetry under market stress, i.e. small minimal returns show lower volume dependence than large maximal returns. We argue that our results are more consistent with a Gennotte and Leland (1990) misinterpretation hypothesis for market crashes than with cascade or behavioral explanations which associate high volume with steep price declines.

We study the spatial volume dependence of electric flux energies for SU(2) Yang-Mills fields on the torus with twisted boundary conditions. The results approach smoothly the rotational invariant Confinement regime. The would-be string tension is very close to the infinite volume result already for volumes of $(1.2 \ {\rm fm.})^3$. We speculate on the consequences of our result for the Confinement mechanism., 6p, ps-file (uuencoded). Contribution to Lattice'93 Conference (Dallas, 1993). Preprint INLO-PUB 18/93, FTUAM-93/40

Vibrational properties of Ba doped Si clathrate are investigated at high pressures up to 20 GPa by Raman spectroscopy. Vibrations related with Ba encaged in the Si cages are observed below $100\text{ }\text{ }{\mathrm{c}\mathrm{m}}^{\ensuremath{-}1}$ by low-frequency Raman measurements of ${\mathrm{B}\mathrm{a}}_{8}{\mathrm{S}\mathrm{i}}_{46}$ and ${\mathrm{B}\mathrm{a}}_{6.6}{\mathrm{S}\mathrm{i}}_{46}$ clathrates. The high-pressure Raman spectra obtained for both compression and decompression processes reveal a new phase transition at 7 GPa, and the reversibility of the phase transition at 15 GPa. We investigate the mechanisms of these phase transitions, the interaction between the guest and host frame, and the volume dependence of the vibrational modes.

The domain wall fermion (DWF) method, with its almost perfectly preserved chiral symmetry on the lattice, makes the calculation of the nucleon axial charge particularly easy. By maintaining chiral symmetry and using the Ward-Takahashi (WT) identity, one has Z_A = Z_V and the bare lattice calculation yields the physical value without explicit renormalization. The DBW2 improved gauge action provides further enhancement of the symmetry and hence a more accurate WT identity at coarse lattice spacing. Taking advantage of these methods, we confirmed a significant volume dependence of the nucleon axial charge on (1.2 fm)^3 and (2.4 fm)^3 lattice volumes., For the RBC Collaboration, Lattice2002(matrixel)

This study was carried out in order to derive the radiobiological parameters of the dose–response relation for the obliteration of arteriovenous malformation (AVM) following single fraction stereotactic radiotherapy. Furthermore, the accuracy by which the linear Poisson model predicts the probability of obliteration and how the haemorrhage history, location and volume of the AVM influence its radiosensitivity are investigated. The study patient material consists of 85 patients who received radiation for AVM therapy. Radiation-induced AVM obliterations were assessed on the basis of post-irradiation angiographies and other radiological findings. For each patient the dose delivered to the clinical target volume and the clinical treatment outcome were available. These data were used in a maximum likelihood analysis to calculate the best estimates of the parameters of the linear Poisson model. The uncertainties of these parameters were also calculated and their individual influence on the dose–response curve was studied. AVM radiosensitivity was assumed to be the same for all the patients. The radiobiological model used was proved suitable for predicting the treatment outcome pattern of the studied patient material. The radiobiological parameters of the model were calculated for different AVM locations, bleeding histories and AVM sizes. The range of parameter variability had considerable effect on the dose–response curve of AVM. The correlation between the dosimetric data and their corresponding clinical effect could be accurately modelled using the linear Poisson model. The derived response parameters can be introduced into the clinical routine with the calculated accuracy assuming the same methodology in target definition and delineation. The known volume dependence of AVM radiosensitivity was confirmed. Moreover, a trend relating AVM location with its radiosensitivity was observed.

Depth, number, and shape of the basins of the potential energy landscape are the key ingredients of the inherent structure thermodynamic formalism introduced by Stillinger and Weber [F. H. Stillinger and T. A. Weber, Phys. Rev. A 25, 978 (1982)]. Within this formalism, an equation of state based only on the volume dependence of these landscape properties is derived. Vibrational and configurational contributions to pressure are sorted out in a transparent way. Predictions are successfully compared with data from extensive molecular dynamics simulations of a simple model for the fragile liquid orthoterphenyl., Comment: RevTeX4, 4 pages, 5 figures

A tight-binding model is fit to first-principles calculations for copper that include structures distorted according to elastic constants and high-symmetry phonon modes. With the resulting model the first-principles-based phonon dispersion and the free energy are calculated in the quasi-harmonic approximation. The resulting thermal expansion, the temperature- and volume-dependence of the elastic constants, the Debye temperature, and the Gruneisen parameter are compared with available experimental data., submitted to Physical Review B

We present excitation spectra for Ce metal obtained with an ab initio scheme combining local density approximation and dynamical mean-field theory including itinerant spd and correlated f states. The local interactions among the f electrons lead to typical many-body resonances in the f density of states (DOS), such as lower and upper Hubbard bands and the Kondo resonance. The spd DOS show weak renormalization effects due to hybridization. We observe different Kondo temperatures for alpha- and gamma-Ce due to strong volume dependence of the effective hybridization strength for the localized f electrons. Finally we compare our results with a variety of experimental data.

The volume dependence of respiratory resistance (Rrs), usually observed during normal breathing, is expected to be accentuated during expiratory flow limitation (EFL). In order to quantify this dependence we studied the pressure, flow, and volume data obtained from eight New Zealand rabbits, artificially ventilated at different levels of applied expiratory pressure (0-10 hPa), before and during histamine i. v. infusion. EFL was provoked by lowering the expiratory pressure and was detected by the application of an additional negative expiratory pressure and by forced oscillations. The analysis of respiratory system mechanics was performed by multiple regression, using the classical linear first-order model and also a nonlinear model, accounting for volume dependence of Rrs. Both models satisfactorily fitted the data in the absence of EFL. The nonlinear model proved to be more appropriate in the presence of EFL. The coefficient expressing the volume dependence of Rrs (Rvd) was significantly more negative during EFL. Rvd values were highly correlated with the fraction of the tidal volume left to be expired at the onset of EFL. A threshold Rvd value of -1,000 (hPa x s x l(-2)) detected EFL with high sensitivity and specificity. We conclude that a strongly negative volume dependence of Rrs is a reliable and noninvasive index of EFL during artificial ventilation.

We investigate the large distance behavior of the electric and magnetic propagators of hot SU(2) gauge theory in different gauges using lattice simulations of the full 4d theory and the effective, dimensionally reduced 3d theory. A comparison of the 3d and 4d data for the propagators suggests that dimensional reduction works surprisingly well down to temperatures T=2 T_c. A detailed study of the volume dependence of magnetic propagators is performed. The electric propagators show exponential decay at large distances in all gauges considered and a possible gauge dependence of the electric screening mass turns out to be statistically insignificant., Comment: Submitted to Proceedings of Lattice 2000 and Workshop "Strong and Electroweak Matter 2000". LaTeX uses espcrc2.sty

The onset critical temperature T co, of CaLaBaCu3O7, is measured as a function of pressure by means of a cryogenic diamond anvil cell. We find ∂T co/∂p = 0.14 ± 0.02K/GPa. The pressure dependence of the upper critical field B c2 as a function of pressure is determined for T/Tc , = 0.96. From this we found the corresponding volume dependence of the number of charge carriers to be much smaller than the value derived from Hall effect measurements in YBa2Cu3O7. Les derivees par rapport a la pression de la temperature critique superieure Tco , (avec ∂T co,⊟∂p = 0.14 ± 0.02K/GPa) et du champs critique B c2 a T/Tc , = 0.96 ont ete determine a l'aide d'une presse a diamants. Pour le compose CaLaBaCu3O7, la variation de la densite de charges en fonction du volume est beaucoup plus faible que celle determiee par effet Hall dans YBa2Cu3O7.

We present hadron mass spectrum results for valence Wilson fermions obtained from simulations on the GF11. We performed high statistic runs on three physical volumes, 8 3 × 32, 16 3 × 32, and 24 3 × 32, all with the same coarse lattice spacing, β = 5.7. We see no systematic difference between our 8 3 and 16 3 results at the large quark masses we could simulate on 8 3 . Our 16 3 and 24 3 results also agree at the small quark masses we simulated on these larger volumes.

The superconducting transition temperature ${\mathit{T}}_{\mathit{c}}$ of metallic glasses ${\mathrm{Fe}}_{20}$${\mathrm{Zr}}_{80}$, ${\mathrm{Fe}}_{25}$${\mathrm{Zr}}_{75}$, and ${\mathrm{Cu}}_{25}$${\mathrm{Zr}}_{75}$ were measured under quasihydrostatic pressure up to 10 GPa. The volume (pressure) dependence of the electron-phonon coupling parameter, ${\ensuremath{\lambda}}_{\mathit{e}\mathrm{\ensuremath{-}}\mathrm{ph}}$, for ${\mathrm{Cu}}_{25}$${\mathrm{Zr}}_{75}$ was calculated using the McMillan equation. Using this volume dependence of ${\ensuremath{\lambda}}_{\mathit{e}\mathrm{\ensuremath{-}}\mathrm{ph}}$ and the modified McMillan equation, which incorporates spin fluctuations, we determined the volume dependence of the spin-fluctuation parameter, ${\ensuremath{\lambda}}_{\mathrm{SF}}$, in ${\mathrm{Ni}}_{25}$${\mathrm{Zr}}_{75}$ and ${\mathrm{Fe}}_{100\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Zr}}_{\mathit{x}}$ (x=80, 75). It was found that with increasing pressure spin fluctuations are suppressed at a faster rate in ${\mathrm{Fe}}_{100\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Zr}}_{\mathit{x}}$ as the Fe concentration is increased. The rate of suppression of spin fluctuations with pressure was also found to be higher in the Fe-Zr glasses than in Ni-Zr glasses of similar composition.

The magnetic phase diagram $T_c(P)$ of the weak itinerant helimagnetic compound MnSi is reviewed upon a Nuclear Magnetic Resonance (NMR) experiment. We present a systematic study on the evolution of the NMR spin echo signal at $T=1.4$ K of the non-magnetic silicone sites, $^{29}$Si, up to 17.8 kbar. The pressure effect is interpreted as a weak variation of the local electronic spin polarization and the coexistence of magnetic and non magnetic Mn atoms under pressure. From the volume dependence of $f_0$ ($P$), we show notably that a local magnetic order remains above the critical pressure of $P_c=14.8$ kbar., 9 pages, 2 figures. To be published in the Review of High Pressure Science and Technology

The magnetization M(H) has been measured in the weakly helimagnetic itinerant compound MnSi under high pressure up to 10.2 kbar and high magnetic field up to 9 Tesla. We interpret the simultaneous decrease under pressure of the saturated magnetization, $p_s$, and the Curie temperature, $% T_c$ in the frame of the self-consistent renormalization theory (SCR) of spin fluctuations. From the analysis of the so-called Arrot-plot ($H/p [ H,T ] $ versus $p^2[ H,T ] $) and the respective volume dependence of $p_s$ and $T_c$, we estimate the evolution of the characteristic spin fluctuation temperatures, $T_0$ and $T_A$ when the system approaches its critical pressure, $P_c$=15 kbar, corresponding to the disappearance of the long range magnetic order at T=0., Comment: 12 pages, 5 figures. Submitted to Phys. Rev. B

Hydrophobicity values for amino acids obtained from protein unfolding experiments are about twice as large as those obtained from data on the partitioning of amino acids between water and octanol. Quantitative analyses of several data sets, presented here, indicate that the difference is best explained by the most direct hypothesis, i.e. that the environment of hydrophobic groups in the interior of a protein is poorly modeled by octanol. Instead, we propose--and provide supporting evidence--that hydrocarbons are a more suitable model. First, we reanalyze data from both solute partitioning and protein unfolding experiments, taking account of the effects that were omitted previously, by introducing a volume dependence in the former and a full free energy analysis in the latter. Both changes in evaluation methodology decrease the discrepancy, but the differences remain substantial. The hydrophobicity parameter obtained from side-chain transfers between octanol and water increases from 16.7 to 22 cal/mol/Angstrom2, while that obtained from protein unfolding decreases from 34.9 to 31.2 cal/mol/Angstrom2. On the other hand, our analysis of the solubilities of pure hydrocarbons in water provides a hydrophobicity parameter of 30.8 cal/mol/Angstrom2. This apparent hydrocarbon-like environment of a protein's interior is also suggested more directly by an analysis of the contact environment of hydrophobic side chains in mutation/unfolding experiments, which have polar contact areas that are

We extract scattering phases for fermion-fermion scattering from Monte Carlo simulations of the two-dimensional Gross-Neveu model. This is done by means of L\"uscher's method, which exploits the volume dependence of the energies of two-particle states. The results are compared with the analytical predictions., Comment: 4 pages, uuencoded compressed Postscript, contribution to Lattice 95, also available at ftp://thphys.physik.rwth-aachen.de/pub/scat/lat95-prep.ps.gz

Theoretical development on the magnetic isotherm in itinerant electron ferromagnets is briefly reviewed in comparison with observed magnetization measurements. Itinerant electron metamagnetic transitions originate from the magnetization curve derived from the negative fourth expansion coefficient of the free energy in magnetization. In our view, however, it is difficult to expect the negative coefficient of the magnetic origin. We therefor propose a new mechanism of the metamagnetic transition, by taking an explicit account of volume dependence of the free energy, which is consistent with our spin fluctuation theory of magnetic isotherms.

To obtain the temperature T and volume V (or pressure P) dependence of the Anderson-Gruneisen parameter δ T , measurements with high sensitivity are required. We show two examples: P, V, T measurements of NaCl done with the piston cylinder and elasticity measurements of MgO using a resonance method. In both cases, the sensitivity of the measurements leads to results that provide information about δ T (η, T), where η ≡ V/V 0 and V 0 is the volume at zero pressure. We demonstrate that determination of δ T leads to understanding of the volume and temperature dependence of q = (∂ ln γ/∂ ln V) T over a broad V, T range, where γ is the Gruneisen ratio.

The Gruneisen ratio, γ, is defined as γy=αKTV/Cv. The volume dependence of γ(V) is solved for a wide range in temperature. The volume dependence of αKT is solved from the identity (∂ ln(αKT)/∂ ln V)T ≡ δT-K′. α is the thermal expansivity; KT is the bulk modulus; CV is specific heat; and δTand K′ are dimensionless thermoelastic constants. The approach is to find values of δT and K′, each as functions of T and V. We also solve for q=(∂ ln γ/∂ ln V) where q=δT-K′+ 1-(∂ ln CV/∂ ln V)T. Calculations are taken down to a compression of 0.6, thus covering all possible values pertaining to the earth's mantle, q=∂ ln γ/∂ ln V; δT=∂ ln α/∂ ln V; and K′= (∂KT/∂P)T. New experimental information related to the volume dependence of δT, q, K′ and CV was used. For MgO, as the compression, η=V/V0, drops from 1.0 to 0.7 at 2000 K, the results show that q drops from 1.2 to about 0.8; δT drops from 5.0 to 3.2; δT becomes slightly less than K′; ∂ ln CV/∂ In V→0; and γ drops from 1.5 to about 1. These observations are all in accord with recent laboratory data, seismic observations, and theoretical results.

To elucidate the influence of hydrogenation on the volume dependence of the Curie temperature TC and the entropy change ΔSm in La(Fe0.86Si0.14)13, magnetic properties under hydrostatic pressure have been investigated. In the thermomagnetization curves of La(Fe0.86Si0.14)13H1.1, the first-order phase transition becomes clearer due to the decrease of volume, as observed before hydrogenation. By hydrogenation, the reduction of the pressure dependence of TC by about 20% is caused by the magnetovolume contribution to the free energy. Meanwhile, the maximum value of ΔSm is increased in magnitude from -9 to -18 J/kgK by applying pressure of 1 GPa. Accordingly, the decrease of volume is also effective to enhance ΔSm after hydrogenation.

I develop a diagrammatic method for calculating chiral logarithms in the quenched approximation. While not rigorous, the method is based on physically reasonable assumptions, which can be tested by numerical simulations. The main results are that, at leading order in the chiral expansion, (a) there are no chiral logarithms in quenched $f_\pi$, for $m_u=m_d$; (b) the chiral logarithms in $B_K$ and related kaon B-parameters are, for $m_d=m_s$, the same in the quenched approximation as in the full theory; (c) for $m_\pi$ and the condensate, there are extra chiral logarithms due to loops containing the $\eta'$, which lead to a peculiar non-analytic dependence of these quantities on the bare quark mass. Following the work of Gasser and Leutwyler, I discuss how there is a predictable finite volume dependence associated with each chiral logarithm. I compare the resulting predictions with numerical results: for most quantities the expected volume dependence is smaller than the errors, but for $B_V$ and $B_A$ there is an observed dependence which is consistent with the predictions., Comment: 43 page latex file, 16 postscript figures included

The passive exhalation flow-volume plots of preterm lambs exhibit curvature. To explain this curvature, we proposed two mathematical models that could predict the measured passive exhalation flow-volume data well. One model takes into account the flow and volume dependence of resistance and compliance. The second model emphasizes the time dependence of lung mechanics and considers the respiratory system viscoelastic properties and the analogy of the lung to two electronic resistor-capacitor circuits connected in parallel. We attempted to determine which of the two models is more valid by analyzing passive exhalation flow-volume data that were obtained while briefly obstructing flow midway through deflation. In 14 preterm lambs (130 d gestation), the flow of exhaled gas increased from 76 ± 35 mL/s when measured just before obstruction to 90 + 30 mL/s when measured immediately after release of the obstruction (p < 0.0001). This finding suggests that a time-dependent phenomenon was taking place during obstruction and is inconsistent with the model based upon the flow and volume dependence of resistance and compliance. We made similar measurements in four near-term (143–146 d gestation) and four full-term lambs (9–12 d of age). Their flow-volume curves were relatively linear, and they showed no increases in flow after removal of the obstruction. The results of this study strongly suggest that time-dependent phenomena caused the curvilin earity in the passive exhalation flow-volume plots of preterm lambs. We suspect that the time-dependent phenomena is associated with the premature lung and with parenchymal lung disease. The models of viscoelastance and of parallel inhomogeneities in the lung are consistent with our observations.

The rate of increase of outflow facility (the wash-out rate) was measured in bovine eyes at 6 and 15 mm Hg. The time-rate-of-change of facility was less at 6 mm Hg (0.20: delta facility/hour) than at 15 mm Hg (0.44). However, when the data was analyzed as a function of volume passing through the outflow system, the volume-rate-of-change of facility was the same at 6 (0.35: delta facility/ml) and 15 mm Hg (0.34). This was consistent with the hypothesis of macromolecules "washing-out" of the aqueous outflow system, if these macromolecules were saturable in the perfusate.

The experimental investigation of low-frequency noise properties in new materials is very useful for the understanding of the involved physical transport mechanisms. In this paper it is shown that, when contact noise is present, the experimental values of the normalized Hooge parameter show a fictitious linear dependence on the volume of the analyzed samples. Experimental data on noise measurements of La0.7Sr0.3MnO3 thin films are reported to demonstrate the validity of the analysis performed. (C) 2008 American Institute of Physics.