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The volume dependence of the Gruneisen parameter has been used to calculate the pressure dependence of melting temperature using Lindemann law. The volume dependence of the Gruneisen parameter for some transition metals viz, Cu, Ni, Pd, and Pt has been determined using Shanker reciprocal relationship between γ and the ratio of pressure and bulk modulus. In this study, volume dependence of the Gruneisen parameter for some transition metals using the Stacey and Davis formulations for infinite pressure. The results for γ have been found similar from both the formulations given by Shanker and Stacey-Davis. The values of melting temperature are calculated and different pressures and Equation of state compared with the available data reported in the literature.

We have investigated the volume effects on hydrogen diffusion properties in both sorption and desorption processes by employing a volumetric analysis technique. The total uptake (𝐶∞), total desorbed content (𝐶0), sorption diffusion coefficient (Ds), desorption diffusion coefficient (Dd), sorption and desorption equilibrium time of hydrogen in two rubbery polymers are determined relative to the diameter and thickness of the cylindrical sample in the two processes. 𝐶∞ and 𝐶0 do not demonstrate the appreciable volume dependence for all rubbers. The identical values in 𝐶∞ and 𝐶0 indicate the reversibility between sorption and desorption, which is interpreted by the occurrence of physisorption rather than chemisorption by introducing hydrogen molecules. The larger Dd values in the desorption process than Ds may be attributed to increased amorphous phase and volume swelling caused by increased hydrogen voids and polymer chain scission after decompression. The time to reach equilibrium in both sorption and desorption processes was found to be linearly proportional to the square of thickness above an aspect ratio of 3.7, which is consistent with the numerical simulations based on the solution of Fick’s law. This finding could be used to predict the equilibrium adsorption time depending on the sample size in the polymer.

We have used a method for determining volume dependence of the Grüneisen parameter in the Lindemann law to study the pressure dependence of melting temperatures in case of 10 metals viz. Cu, Mg, Pb, Al, In, Cd, Zn, Au, Ag and Mn. The reciprocal gamma relationship has been used to estimate the values of Grüneisen parameters at different volumes. The results for melting temperatures of metals at high pressures obtained in this study using the Lindemann law of melting are compared with the available experimental data and also with the values calculated from the instability model based on a thermal equation of state. The analytical model used in this study is much simpler than the accurate DFT calculations and molecular dynamics.

This paper presents a quantitative method for predicting the experimental value of the tensile strength of a polymer material by using molecular dynamics (MD) simulation. Because the tensile strength obtained by MD simulation is almost always higher than the experimental value, a solution is suggested in the present study. Several simulations varying simulation volumes (i.e., number of molecules) and tensile loading speeds (i.e., strain rate) were implemented; the results confirmed that the tensile strength decreases with increasing simulation volume and decreasing strain rate. Firstly, strength as a function of the simulation volume was determined based on Weibull statistics and then the relationship was extrapolated to a much higher number of molecules, which was equivalent to a real specimen. Secondly, the relationship between the tensile strength and strain rate was determined and it was extrapolated to match the strain rate in actual experiments. Consequently, a predicted strength was close to the experimental result.

In chemical reaction networks, bistability can only occur far from equilibrium. It is associated with a first-order phase transition where the control parameter is the thermodynamic force. At the bistable point, the entropy production is known to be discontinuous with respect to the thermodynamic force.We show that the fluctuations of the entropy production have an exponential volume-dependence when the system is bistable. At the phase transition, the exponential prefactor is the height of the effective potential barrier between the two fixed-points. Our results obtained for Schl\"ogl's model can be extended to any chemical network., Comment: 9 pages, 2 figures

PURPOSE Dose painting techniques based on dose escalation to hypoxic regions are usually governed by the spatial distribution of Oxygen Enhancement Ratio (OER) derived from PET or MRI images. The goal of this article is to show that the volume of the hypoxic region is also a parameter which may affect the radiobiological effectiveness of hypoxia-targeted dose escalation. METHODS Our analysis is performed using the equation for Tumor Control Probability (TCP) derived from Poisson statistics. A tumor response model based on two levels of oxygenated and hypoxic cells with the survival curves described by the Linear Quadratic (LQ) model was used in the calculations. The model allows for analytical solutions which can be used for additional validation of our numerical simulations. The model was used to compute the average tumor cell survival that defines TCP. Dependence of average tumor cell survival on the relative hypoxic volume and dose escalation was computed for the conventional 30 × 2 Gy and hypofractionated 4 × 12 Gy dose regimens in a model problem with radiobiological parameters for nonsmall cell lung cancer. RESULTS We show that equal average tumor cell survival and TCP can be achieved with smaller hypoxia-targeted dose escalation for smaller relative hypoxic volumes if the dose escalation does not exceed 50% of dose in the oxygenated region. This effect is explained by the dependence of average tumor cell survival and TCP mostly on the hypoxic tumor volume in this dose escalation range. Assuming a linear relationship between the number of clonogens and the hypoxic volume, smaller hypoxic volumes have smaller number of clonogens, therefore, smaller doses are needed to eradicate them. CONCLUSIONS The theoretical analysis performed in this article predicts that tumors with smaller relative hypoxic volumes may require smaller hypoxia-targeted dose escalation to maintain equal TCP. The results of this research can be used for dose de-escalation strategies in dose painting techniques which may reduce dose to normal tissue and normal tissue complications without deterioration of TCP.

Long-term thermal stability of nickel line patterns was investigated. 5 μm-wide patterns and 20 μm-wide patterns were deposited with four different thicknesses, and their morphological change was compared after heat treatment. Displaced volume was calculated by post-annealing image analysis. Opposite coarsening trends were found for the two tested widths. 20 μm-wide patterns show deviation from predictions of previous models, but they still behave as expected: thinner pattern shows higher mobility. This is reversed for 5 μm-wide patterns. Surface tension at the metal-gas interface, the usual driving force behind coarsening, can still explain the unexpected displaced volume dependence on thickness.

The theoretical models recently used by Chandra [Computational Condensed Matter 27 (2021) e00556] for computing the Gruneisen parameter are not valid at extreme compression but are valid at small compressions. Values of critical pressure for the validity of the Chandra models are about 24 GPa for e -Fe and 3.5 GPa for NaCl. It is emphasized that the third order Gruneisen parameter assumed by Chandra to remain constant for materials under the effect of pressure is not consistent with the recent investigations. We have developed a method for determining the volume dependence of Gruneisen parameter by taking into account the pressure dependence of third order Gruneisen parameter. The results have been obtained for e -Fe and NaCl which differ appreciably at high pressures from those computed by Chandra taking a constant value of third order Gruneisen parameter.

This paper examines the return–volume dependence structure across six major international stock markets using a dependence-switching copula model. The model allows the return–volume dependence to switch between positive and negative dependence regimes. The empirical results indicate that the return–volume (tail) dependence is asymmetric under the negative and positive dependence regimes, respectively. Next, there is a larger return–volume (tail) dependence for downward price ticks than for upward price ticks when trading volumes are large for most countries, supporting the view of heterogeneous investors with short-sale constraints and negative skewness in returns. Finally, both the intensity of information flow and liquidity trading are important driving forces of the time-varying, return–volume dependence.

Nowadays Bitcoin as cryptocurrency takes a significant place on the global financial markets. This paper analyzes the Bitcoin closing prices and traded volume during the period from December 28, 2013 to January 22, 2019. This period is known as a period with rapid increasing of the Bitcoin closing prices, mainly in the second half of the year 2017. The aim of this paper is twofold. First, we compute the Hurst coefficient to discover the close price dynamics and traded volume using a fractal point of view. We have discovered an anti-persistent behavior in the traded volume and random character of bitcoin closing prices. Second, we propose an analysis of the relationship between the close prices and traded volume. Our findings show how changes in the high-price period differ from changes in the low-price period. We also found that high prices caused investors to be afraid to trade due to possible rapid decrease in bitcoin closing prices.

We have analyzed in the two different models of volume dependence of Gruneisen parameter (γ). The initial Gruneisen parameter γ0 and its logarithmic volume derivatives so called the third order Gruneisen parameter (λ) are obtained from the fitting of experimental data in e-Fe, NaCl, K, Li, and Na solids. We also determined the second order Gruneisen parameter ( q 0 ) using the initial and third order Gruneisen parameters. The calculated results of γ 0 are in good agreement with the experimental data for the case of different solids. The results of q 0 parameter are compared with the other methods of calculation. A comparison result of the two parameters q 0 and λ based on the two models has been presented for the different solids.

We develop a multivariate return and trading volume model, where each stock’s system is driven by latent information arrivals in continuous time. The arrivals contain idiosyncratic and cross-relevant information, which provides both return and trading volume dependence. Conditional on the accumulated information, returns are jointly normal and correlated, which implies a second layer of dependence in the return dimension. Using a sample of nine common stocks, we show that trading volume significantly adds to the operationalization of the latent information flow process driving the contemporaneous return distribution. The dependence parameter estimates provide significant and interpretable degrees of information flow dependence across all results. Portfolio risk measurement applications are extended by conditioning on the level of trading volume, e.g. reflecting stress, leading to an accurate risk quantification.

The bond ionicity in seventy two A N B 8− N compounds is investigated according to the recently introduced first-principles ionicity scale, based on the centers of the maximally localized Wannier functions, which has several interesting features. The obtained bond ionicities ( q i ) are found to exhibit the expected trends, according to electronegativity arguments. In particular, the bond ionicity in the alkaline-earth oxides increases by going from MgO to BaO. A strong crystal structure dependence of q i is observed. A critical value of q i (of 0.91) that separates between the tetrahedrally and octahedrally coordinated systems is inferred directly from the calculated values of q i . The volume dependence of q i is investigated for all the considered compounds and found to reduce by volume decrease for most of the studied systems. The adopted ionicity scale is established as a very strong competitor to the most widely accepted Phillips and Pauling ionicity measures.

We compare two expressions for the volume dependence of the Gruneisen parameter γ for fcc Al presented by Burakovsky and Preston (2004) [3] and Jacobs and Schmid-Fetzer (2010) [4], respectively. It’s found that both calculated results of the melting temperature Tm are in good agreement with experimental data. But the higher order Gruneisen parameters are different. We obtain the values of the third order Gruneisen parameter λ∞ and the pressure derivative of bulk modulus K′∞ at extreme pressure, and the parameter f in the generalized free volume formula for the two models. The results show that the Jacobs’s expression of Gruneisen parameter is more suitable for fcc Al.

Marija Damjanovska,1 Tatjana Stopar Pintaric,1,2 Erika Cvetko,2 Kamen Vlassakov3 1Clinical Department of Anesthesiology and Intensive Therapy, University Medical Centre Ljubljana, Ljubljana, Slovenia; 2Institute of Anatomy, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia; 3Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA Purpose: The ultrasound-guided retrolaminar block is one of the newer and simpler alternatives to the traditional, often technically challenging, paravertebral (PV) block. Its feasibility, safety, and efficacy have already been clinically demonstrated in patients with multiple rib fractures using higher volumes of local anesthetic, when compared with the traditional approach. The primary aim of this observational anatomical study was to assess the spread of local anesthetic from the retrolaminar injection point to the PV space and its volume dependence. Second, we assessed the incidence of epidural and contralateral PV spread in the both groups.Methods: Ten fresh porcine cadavers were randomized into 2 groups (n=5 each) to receive ultrasound-guided retrolaminar injections at Th4-Th5 level with either 10 mL (low-volume group) or 30 mL (high-volume group) of 2% lidocaine and methylene blue mixture. After the procedure, the cadavers were dissected and frozen. Cross-section cuts (~1 cm thick) were performed to evaluate the injectate spread.Results: In the high-volume group, injectate spread from the retrolaminar to the PV space was observed in all specimens (5 out of 5; 100%), while in the low-volume group, no apparent spread to the PV space was found (0 out of 5; 0%). No epidural or contralateral PV spread was observed in any of the specimens.Conclusion: Following ultrasound-guided retrolaminar injections in fresh porcine cadavers, injectate spread from the retrolaminar tissue plane to the PV space is strongly volume dependent, suggesting that, clinically, high local anesthetic volumes maybe critical for achieving regional anesthesia and analgesia consistent with traditional PV blockade. Keywords: paravertebral space, vertebral lamina, local anesthetic, injections&nbsp

Airway obstruction is the main feature of asthma but the precise intrathoracic localization may be difficult to assess using standard lung function. The flow and volume dependence of respiratory resistance (Rrs) by forced oscillations during respiratory cycle may provide an insight. The aim of this study was to describe the pattern of within-breath variations of Rrs in children with exercice-induced bronchoconstriction. Children undergoing an exercise testing were recruited between 2014 and 2016. Rrs at 12 Hz and spirometry were measured at baseline and 5 min after challenge. The volume and flow dependence of Rrs were analyzed by least square regression (Rrs = K1 + K2|V’| + K3V, where K1 and K2 are Rohrer’s constants and K3 expresses the negative volume dependence of Rrs) and assessed separately in inspiration (i) and expiration (e). The different parameters at baseline and after exercise were compared between children with a positive response (Ex+, decrease in forced expiratory volume in 1s >8% from baseline) and a negative response (Ex-). Rrsi, e, K1i, e and K2i, e were not different between the 2 groups at baseline (4±2 hPa.s/L in Ex+ vs 5±2 hPa.s/L in Ex- for Rrsi, respectively 4.7±2 hPa.s/L in Ex+ vs 5.5±2 hPa.s/L in Ex- for Rrse) or after challenge (6±3 hPa.s/L in Ex+ vs 5±2 hPa.s/L in Ex- for Rrsi, respectively 6±3 hPa.s/L in Ex+ vs 5±2 hPa.s/L in Ex- for Rrse). K3i, e was significantly more negative in Ex+ group after challenge but not at baseline, vs Ex- group (p It is concluded that volume dependence of Rrs rather than Rrs is associated with exercise induced flow limitation, and appears as a specific indicator of the intrathoracic airway response to exercise.

The magnetic properties tuning and volume dependence in the series of quaternary full Heusler alloys with formula Co2Cr1−xYxGa (Y=Ti, V, Mn, Fe, Co, Ni) were studied with a detailed first-principles exploration. We employ the density functional KKR method with the coherent potential approximation, estimating effective Heisenberg exchange constants via the magnetic force theorem together with mean-field Curie temperature (TC) and magnetic moment for compositions in the whole concentration range. The volumetric dependency of these magnetic properties is studied, particularly the pressure derivatives of TC at equilibrium. Our ternary alloy calculations show good agreement with local-density and generalized gradient approximations in the literature. The quaternary alloys show a wide range of tunable magnetic properties, where magnetic moments range from 0.8 to 4.9 μB, TC from 130 K to 1250 K, and dTC/dV values range from −7 to +6.3KÅ−3 published

A new computing model on the volume dependence of the product αKT of the thermal expansion coefficient α and the isothermal bulk modulus KT is proposed straightforward in this paper. Based on this revised formula, the volume dependence of Grüneisen parameter, entropy, Anderson-Grüneisen parameter, and first pressure derivative of bulk modulus, respectively, are thus investigated. The calculated results agree well with the previous work for magnesium oxide, sodium chloride, lithium, sodium, and potassium.

We studied the shape of water droplets deposited using an inkjet nozzle on a chemically striped patterned substrate consisting of alternating hydrophobic and hydrophilic stripes. The droplet dimensions are comparable to the period of the stripes, typically covering up to 13 stripes. As such, our present results bridge the gap linking two regimes previously considered: (i) droplets on single stripes and (ii) droplets covering more than 50 stripes. In line with previous work on markedly smaller water droplets, the exact deposition position is important for the final shape of the droplets. A droplet with its center deposited on a hydrophobic stripe reaches a shape that is different than when it is deposited on a hydrophilic stripe. Experimental results of different droplet configurations on the same surface are in agreement with simulations using the lattice Boltzmann model. In addition, the simulations enable a detailed analysis of droplet free energies and the volume dependence. The latter reveals scaling properties of shape parameters in terms of droplet radius scaled to the period of the stripe pattern, which have remained unexplored until now.

A comprehensive and systematic study of superconducting state parameters (SSPs) of Bi-based binary alloys of the form [Formula: see text] has been carried out in the framework of pseudopotential theory at different concentrations ([Formula: see text]) of impurity atom-[Formula: see text] in host atom Bi which varies from 0 to 1. Impurity atom [Formula: see text] has been replaced by In, Tl, Sb and Pb to form four alloy systems. The density-based local form of the pseudopotential proposed by Fiolhais et al. has been used in this study to compute SSPs such as electron–phonon coupling strength ([Formula: see text]), Coulomb pseudopotential ([Formula: see text]), transition temperature ([Formula: see text]), effective interaction strength ([Formula: see text] and isotopic effect parameter ([Formula: see text]) of Bi-based binary alloy systems. Computed results of SSPs of alloys under study are in good agreement with available experimental and other theoretical results. In order to investigate the effect of pressure on SSPs of alloys under study, a theoretical calculation of SSPs as a function of compressed volume is reported. The volume dependence of Debye temperature has been accounted by using Debye–Gruneisen model which involves the Gruneisen parameter. Thus, to describe the effect of pressure on SSPs accurately, the value of Gruneisen parameter should be as accurate as possible. But reported results of Gruneisen parameter in the literature are highly scattered. Due to this reason, we have used two sets of Gruneisen parameter obtained by different methods to understand its role in the computation of SSPs as a function of compressed volume. Further, critical volumes for all alloys at different concentration have been predicted at which electron–phonon coupling strength and Coulomb pseudopotential are equal ([Formula: see text]). At critical volume, superconductivity quenches where transition temperature, [Formula: see text], and effective interaction strength, [Formula: see text], become zero. It is observed that critical volumes predicted by all approaches used in this study are in excellent agreement with each other.

To study the formation mechanism of the long-period stacking ordered (LPSO) structures, the reaction pathways of solid–solid transformations from a hexagonal close-packed (HCP) structure to LPSO structures in Mg-Y-Zn alloys were calculated using the generalized solid-state nudged elastic band method. The energy increases along the transition from HCP to 18R, and the peak positions represent the activation energy for the transition. Y substitution hardly changes the activation energy but makes the 18R-type LPSO structure more stable than HCP. In contrast, Zn or Y + Zn substitution results in higher activation energy and makes the 18R-type LPSO structure less stable than HCP. The calculated results for 14H and 24R LPSO structures also show similar activation energy and LPSO stability to the HCP-18R transition. Therefore, Y substitution plays an important role in stabilizing the stacking faults in LPSO systems. For the microscopic mechanism, the volume dependence of the total energy in pure FCC and HCP Y were examined, and the result suggests that FCC-Y is stable than HCP-Y under pressure. Therefore, the effect of substitution of Y in HCP Mg can be explained by the characteristics of Y under the chemical pressure exerted by the small size of Mg lattice.

Volumetric capnography is a standard method to determine pulmonary dead space. Hereby, measured carbon dioxide (CO2) in exhaled gas volume is analyzed using the single-breath diagram for CO2. Unfortunately, most existing CO2 sensors do not work with the low tidal volumes found in small animals. Therefore, in this study, we developed a new mainstream capnograph designed for the utilization in small animals like rats. The sensor was used for determination of dead space volume in healthy and surfactant-depleted rats ( n = 62) during spontaneous breathing (SB) and mechanical ventilation (MV) at three different tidal volumes: 5, 8, and 11 ml/kg. Absolute dead space and wasted ventilation (dead space volume in relation to tidal volume) were determined over a period of 1 h. Dead space increase and reversibility of the increase was investigated during MV with different tidal volumes and during SB. During SB, the dead space volume was 0.21 ± 0.14 ml and increased significantly at MV to 0.39 ± 0.03 ml at a tidal volume of 5 ml/kg and to 0.6 ± 0.08 ml at a tidal volume of 8 and 11 ml/kg. Dead space and wasted ventilation during MV increased with tidal volume. This increase was mostly reversible by switching back to SB. Surfactant depletion had no further influence on the dead space increase during MV, but impaired the reversibility of the dead space increase.

SrS (rocksalt and CsCl structures). Volume dependence of the Brillouin-zone center phonon frequencies in the low-pressure rocksalt (B1) and high-pressure CsCl (B2) structures from PP-PW-GGA calculations [11S]

We consider a recent T-matrix analysis by Albaladejo et al. (Phys Lett B 755:337, 2016), which accounts for the $$J/\psi \pi $$ and $$D^*\bar{D}$$ coupled-channels dynamics, and which successfully describes the experimental information concerning the recently discovered $$Z_c(3900)^\pm $$ . Within such scheme, the data can be similarly well described in two different scenarios, where $$Z_c(3900)$$ is either a resonance or a virtual state. To shed light into the nature of this state, we apply this formalism in a finite box with the aim of comparing with recent Lattice QCD (LQCD) simulations. We see that the energy levels obtained for both scenarios agree well with those obtained in the single-volume LQCD simulation reported in Prelovsek et al. (Phys Rev D 91:014504, 2015), thus making it difficult to disentangle the two possibilities. We also study the volume dependence of the energy levels obtained with our formalism and suggest that LQCD simulations performed at several volumes could help in discerning the actual nature of the intriguing $$Z_c(3900)$$ state.

The Nie expression is amended in such a way that the expression follows the infinite pressure behaviour, i.e., $P\to \infty $ or V → 0. A new empirical relationship is developed to predict the values of volume dependence of Gruneisen parameter. NaCl and e-Fe have been employed to test the suitability of the expression. The results obtained reveal that the relationship is reliable as there is a good agreement between the calculated and the experimental data.

A revised model of volume dependence of Anderson–Gruneisen parameter for lower mantle under adiabatic condition is presented in this study, and the volume dependence of (α T/C P =α ′) is then discussed. It is shown that the results are in good agreement with seismic data of the Earth.

Using first-principles calculations based on density functional theory, we investigated systematically the electronic structures and magnetic properties of Fe 16 N 2 system and their unit cell volume dependence. It has been found that total magnetic moment increases as increasing unit cell volume of Fe 16 N 2 . In addition, it also has been found that the d electron number on Fe I, Fe II and Fe III atoms decreases as increasing unit cell volume and the local magnetic moment on Fe atoms increases with the decrease of d electron number. The present study provides a clear insight into the numerous conflicting experimental results on the magnetic properties of Fe 16 N 2 system.

We derive a relation for computing volume dependence of entropy at selected isotherms. This formula is based on the Al'tshuler et al. model (J. Appl. Mech. Tech. Phys.28 (1987) 129) for volume dependence of Grüneisen parameter. The formula for entropy obtained in the present study has been used to determine the results for MgO down to a volume ratio 0.50 at selected isotherms. The obtained results for entropy present a general agreement with those calculated by Cynn et al. (J. Phys. Chem.99(9) (1995) 7813). We also formulate a relationship between Debye temperature and entropy. And it is found that Debye temperature increases exponentially as entropy decreases.

International audience; Synchrotron microtomography was used for in-situ characterization of high-temperature creep damage in leaded brass. Applying image registration to subsequent tomographic reconstructions, the volumetric growth rate of single cavities with equivalent radii between 2 and 4.3 mu m was assessed. We conclude from the volume dependence of the growth rates that both the viscous flow and grain boundary (GB) diffusion mechanisms influence void growth. We show that void growth in leaded brass is retarded by negative stress triaxiality, which develops in the matrix during heating the specimen to the deformation temperature.