bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of local orthorhombic distortion in tetragonal double lithium-rare earth molybdates
Authors: Kalinin P. S. , Skorobogatova I. V. , Zvyagin A. I. , Khat'sko E. N. , Yurko V. G.
Published: November 2024

The temperature dependence of the magnetic susceptibility X∥(T) (7) over the range 4.2–100°K has been measured for lithium-praesodymium and lithium-samarium molybdates, which have the scheelite structure. Also, X∥(T) has been calculated taking into account the admixture into the ground states 6H5/2 for Sm3+ and 3H4 for Pr3+ of the excited states 6H7/2 and 3H5, respectively. It is found that the structural disorder in the double scheelites results in small orthorhombic distortions in the local symmetry of the rare earth positions.
Soft phonon mode behavior in the KMnF3 crystal
Authors: Eremenko V. V. , Fomin V. I. , Popkov Yu. A. , Sergienko N. A.
Published: November 2024

The low-frequency region of the Raman spectrum is studied in KMnF3 over the temperature range 4.2–300°K. At low temperatures four lines with frequencies 28, 39.5, 50, and 66 cm−1 were observed. Changes in the spectrum with temperature allow these lines to be ascribed to components of the soft phonon modes Γ25 and M3, which are responsible for phase transitions at 187.6 and 102 °K, respectively. Moreover, an abrupt change in Raman spectrum line frequencies was observed at the temperature of antiferromagnetic ordering, TN = 88°K. Group-theoretical analysis of the spectrum is performed with consideration of condensation of the oscillatory modes Γ25 and M3. On the basis of theoretical and experimental data conclusions are reached as to the symmetry of the KMnF3 crystal in low temperature phases.
On dimensional cyclotron resonance
Authors: Lur’e M. A. , Peschanskii V. G.
Published: November 2024

Cyclotron resonance (CR) in a metal plate whose thickness d is less than the charge-carrier mean free path l and the maximum diameter 2r of the electron orbits in a magnetic field, but considerably greater than the depth δ of electromagnetic wave penetration into the metal is investigated. New resonance frequencies originate in such conductors, which are determined by the characteristics of electrons with an orbit diameter equal to the plate dimension. The influence of the slope of the magnetic field on this dimensional CR is studied for all angles at which it can occur. For quite small slopes φ<δ/l to which CR is not generally sensitive in bulk conductors, in thin specimens d≪δl in the range of angles (d/l)2≪δ/l CR is possible only in higher approximations in the small parameter (d/l)2φ−1. In the domain of larger angles δ/l≪φ≪δ/r Doppler frequency splitting of the dimensional CR occurs. Cyclotron resonance in an oblique magnetic field has the greatest intensity in sufficiently thick conductors when d>(δl)1/2. As φ increases in such conductors, doubling of the resonance frequencies occurs in the range of angles δ/r≪φ<d/l.
The minimum in the thermal conductivity of tantalum
Authors: Ermolaev A. M. , Zlobintsev G. M. , Krasnokutskii A. V. , Merisov B. A. , Khotkevich V. I.
Published: November 2024

Measured values of the thermal conductivity of tantalum samples of various purities at 14–220°K are presented. A minimum is discovered on the thermal-conductivity/temperature curve. The position of the minimum is determined for the pure metal, and so is its displacement under the influence of impurities or lattice defects. The results of the calculations are in excellent agreement with experiment.
Magnetostriction of antiferromagnetic MnF2 in a strong field
Authors: Semenenko L. M. , Dudko K. L.
Published: November 2024

The magnetostriction of a uniaxial MnF2 antiferromagnet is measured at 10°K in a field up to 150 kOe. A jump in the deformation along the axis of crystal symmetry and subsequent quadratic growth are observed in a magnetic field (Hc = 91.7 kOe) parallel to this axis. The deformation grows quadratically in H in a perpendicular field. The jumplike change in the crystal dimensions at H = Hc agrees with the concept of a sublattice-flipped phase transition which occurs in this field. The magnetostriction of MnF2 is explained by the dependence on the anisotropy energy and the exchange energy whose contributions are separated. The experimental results are in good agreement with estimates of the magnitudes of these contributions, obtained on the basis of magnetic dipole and indirect exchange interactions.
Magnetic-field dependence of the electron-phonon interaction in cadmium
Authors: Naberezhnykh V. P. , Naberezhnykh V. V. , Selyakov Β. I.
Published: November 2024

Measurements have been made in a parallel-sided cadmium plate of the temperature dependence of the amplitude of impedance-derivative oscillations produced by the excitation of standing-wave dopplerons. It is shown that the electron-phonon collision frequency increases with the magnetic field.
Superconductivity of metal and metal-polymer organosols
Authors: Khimchenko Yu. I. , Pan V. M. , Berlin A. A. , Fil’ T. I. , Popov A. G. , Khvorov Μ. M. , Zhelibo E. P. , Kushnir V. G.
Published: November 2024

The superconducting properties of granular compounds of a new type, namely electrolytical organosols of metals and metal-polymers, have been investigated. An increase in Tc of the specimens studied as compared with the bulk material and a number of other features characteristic of granular superconductors are found.
Behavior of ErFeO3 magnetic structure at low temperatures
Authors: Klochan V. A. , Kovtun N. M. , Khmara V. M.
Published: November 2024

Spin reorientation in ErFeO3 at low temperatures is studied. It is shown that this process occurs in two stages. In the first stage continuous reorientation of Er3+ spins to the c axis occurs, while in the second these spins are ordered in the configuration Cz, causing reorientation of Fe3+ spins in the plane bc in accordance with the rule sin⁡θ∼μR. Expressions are obtained for Fe57 nuclear magnetic resonance branching and their mean value: Δf=Asin⁡2θ and fav=fo−Bsin2⁡θ, which agree well with experiment. Using experimental data on the value of sinθ the dependence of erbium ion magnetic moment μR on temperature is determined, which near TN has the form characteristic of critical phenomena μR∼(TN2−T)β with exponent β = 0.50 ±0.07.
Spin diffusion in the bcc phase of concentrated 3He-4He solutions
Authors: Grigor’ev V. N. , Esel’son Β. N. , Mikheev V. A.
Published: November 2024

Experimental results are obtained for the diffusion coefficient of 3He, which indicate fairly rapid 3He-4He tunnel exchange in the bcc phase of concentrated 3He-4He solutions. It is found that the diffusion coefficient is dependent on the length of the diffusion path.
Effect of the surface on the electrical conductivity of thin wires
Authors: Pavlov S. D.
Published: November 2024

The electrical conductivity of a cylindrical wire is calculated for an arbitrary angular dependence of the electron specular reflection coefficient q(φ). Asymptotic equations are obtained for the electrical conductivity of an extremely thin specimen which enable one, in particular, to determine the angular dependence q(φ) from measurements of the electrical resistance of thin wires.
The angular dependence of the periods of “high-temperature” oscillations in the magnetoresistance of bismuth
Authors: Bogod Yu. A. , Gerasimechko V. G. , Krasovitskii Vit. B.
Published: November 2024

The angular dependence of the periods of the “high-temperature” oscillations of the magnetoresistance in the three principal crystallographic planes is studied. It is found that several periods can occur for a given direction of the magnetic field, and the angular dependence of the main period of the high-temperature oscillations (HTO) in all planes is similar to the angular dependence of the Shubnikov-de Haas effect for the largest cross section and cyclotron mass. The effect of crystal structure defects (arising during plastic deformation) on the HTO amplitude has been studied. An analysis has been made of the experimental results. A program is mentioned for studies which can uniquely determine the parameters of the energy spectrum of bismuth responsible for the HTO.
Nucleation in first-order phase transitions in magnetic materials
Authors: Nechiporenko I. N.
Published: November 2024

The problem of inhomogeneous states of magnets in the neighborhood of the temperature of a first-order phase transition is considered. Besides the magnetic parameters of the system, the interatomic spacings of the crystal lattice also vary at such a phase transition; hence, the magnetoelastic and elastic energies are taken into account in the thermodynamics of the system. The structure and energy of the interphase transition layer are found. It is shown that the paramagnet-antiferromagnet transitions are accompanied by the appearance of spherical nuclei; estimates are carried out of the nucleation parameters as a result of quantum tunneling. It is shown that the interdomain boundary of an uniaxial ferromagnet is converted into a paramagnetic nucleus at the equilibrium temperature for the ferromagnet-paramagnet transition and an intermediate domain structure of alternating ferromagnetic and paramagnetic phases can exist at this temperature. The paramagnet-ferromagnet and antiferromagnet- ferrimagnet transitions are accompanied by the appearance of nuclei of spherical or extended (along the magnetization) shape. The shape and size of the critical nuclei are determined.
Magnetic and electrical properties of the chalcogenide compound Cd1−XGaXCr2S4
Authors: Belov K. P. , Koroleva L. I. , Batorova S. D. , Gordeev I. V. , Alferova V. A.
Published: November 2024

A study was made of the field dependence of the magnetization at 4.2°K and in the neighborhood of the Curie point, and also of the temperature dependence of the paramagnetic susceptibility of the polycrystalline compound Cd1−x GaxCr2S4 (0.01 ≤ x ≤ 0.15). For a composition with x = 0.15 the temperature dependence of the Hall emf, and of the magneto- and electrical resistance was studied. An absence of saturation on the magnetization curves was observed. The maximum of the resistance in the neighborhood of the Curie point for x = 0.15 is smoothed and is displaced in the high-temperature direction by about 60°. The given phenomena are explained by fluctuations of the magnetic moment connected with fluctuations of the number of carriers.
The effect of magnetic fields on the resistance minimum in praseodymium
Authors: Semenenko E. E. , Tutov V. I.
Published: November 2024

The magnetic field necessary for elimination of the resistance mmtmum in praseodymium containing 0.045% of the magnetoactive impurity iron is determined experimentally. The field value is 93,000 Oe. A new phenomenon has been discovered-a dependence of the resistance minimum temperature on external magnetic field. It has been established that the minimum temperature increases sharply with the increase in external magnetic field from zero to 40,000 Oe (from 3.8 to 4.4°K), tending to saturation upon further increase. A possible cause for the difference in magnetic field needed to eliminate the resistance minimum in chromium and praseodymium is discussed.
A quantum theory of metamagnetism
Authors: Boroviko V. S. , Frishman A. M.
Published: November 2024

Metamagnetic transitions in laminated antiferromagnets are investigated quantum-mechanically. It is shown that in contrast to the results of classical theory the field variations of the magnetization and the phase diagram depend essentially on the spin per lattice site. For s = 1/2, the phase diagrams obtained are similar to those observed for FeCO3.
Acoustic relaxation in liquid methane and tetrafluoromethane
Authors: Mikhailenko S. A. , Dudar' B. G.
Published: November 2024

The absorption α and velocity u of sound are measured in liquid CH4 and CF4 along the saturation line at frequencies from 5 to 126 MHz and temperatures from 90 to 210°K. Dispersion of the quantity α/f2 is observed in CF4 over the entire investigated range of temperatures and frequencies, and slight dispersion of the velocity of sound is observed at low temperatures. Dispersion of α/f2 is observed in CH4 only for T > 140°K. Over the entire temperature range the absorption greatly exceeds the dissipative losses associated with the external thermal degrees of freedom. It is inferred from an analysis of the results that the effects observed in both substances are related to the excitation of intramolecular vibrational degrees of freedom. The resulting vibrational relaxation curves evince different kinetics for this process in the two liquids in connection with the different nature of the rotational motion of the particles.
Many-body and inelastic tunnel spectroscopy of quasiparticle excitations in normal metals (Survey)
Authors: Ivanchenko Yu. N. , Medvedev Yu. V.
Published: November 2024

The review presents modern advances towards the solution of many-body tunneling in metals. The extent to which the fine structure of the current-voltage characteristics can be used for spectroscopy of different types of excitations in electrodes forming a junction is discussed. Theoretical and experimental results are presented for the excess tunnel current components appearing due to self-energy, inelastic, and interference effects.
Effect of topological changes in the Fermi surface on superconducting characteristics of metallic films
Authors: Belogolovskii M. A.
Published: November 2024

The dependence of the energy gap and the critical temperature of thin superconducting films is found in terms of an external parameter, varying with the topology of the Fermi surface. It is shown that the shape of the corresponding curves depends strongly on the type of topological change.
Effect of a constant magnetic field on the yield stress of nickel at 4.2 °K
Authors: Kononenko V. I. , Pustovalov V. V.
Published: November 2024

The effect of the domain structure on the magnitude of the yield stress of 99.8% pure single crystals of nickel is investigated at 4.2°K. The investigation is carried out by means of deformation by extension in longitudinal, transverse, and alternating magnetizing fields which enables us to vary the relative orientation of slip bands and magnetic domain walls. An increase in the yield stress is observed when the extension axis is in the same direction as the magnetization field. A considerably larger hardening effect ( ∼ 20%) is obtained in the loading of crystals in alternating longitudinal and transverse magnetization fields; this can be connected with the fine subdivision of the domain structure during magnetic reversal and its partial pinning during deformation up to the yield stress.
Exciton states in liquid and crystalline xenon
Authors: Kink R. A. , Lôhmus A. É.
Published: November 2024

On the basis of reflection spectra at temperatures 10−168°K, a study is made of exciton states in crystalline and liquid xenon. In both phases excitons of large radius are observed. The reduced mass (μ = 0.27 me) and the exciton radius (r1 = 4.0 Å) and also the energy gap (Eg = 9.28 eV) are determined for crystals from the hydrogen-like series in the spectra. It is found that the first term of the г(3/2) series consists of three subbands: An interpretation of these states is given. It is postulated that in the shortwave region of the absorption band of the “pure” exciton, the exciton state appears together with a defect (vacancy), while in the longwave tail a forbidden transition to the 3P2 level is observed.
Exciton luminescence of solid xenon
Authors: Fugol' I. Ya. , Belov A. G. , Poltoratskii Yu. B. , Savchenko E. V.
Published: November 2024

We have detected free-exciton luminescence in perfect xenon crystals. We observed two new luminescence bands, one of which coincides in resonance with the first band of the Γ(3/2) exciton absorption series, while the other corresponds to intrinsic absorption in the Γ′(3/2) band. We have determined the properties of the exciton luminescence bands and established the basic mechanism of the luminescence in inert-gas crystals.
Spin fluctuations and superconductivity (properties of PdH solutions)
Authors: Kulik I. O.
Published: November 2024

Using a self-consistent treatment of deformation, Coulomb, and exchange effects within the isotropic approximation, a criterion for superconductivity of metals is obtained ps2<N2vFx0x, where ρs2 = c11 is the lattice elastic coefficient, N is the electron concentration, νf is the electron density of states at the Fermi surface, χ is the spin paramagnetic susceptibility of the metal, and χ0=μB2vF is the Pauli paramagnetism. This criterion applies not only to nontransition, but also to transition metals with strong exchange interactions (though not including interband transitions). This is demonstrated on the example of the appearance of superconductivity in solid solutions of hydrogen in palladium PdHx when the hydrogen concentration x is varied.
Pitch angle and altitude control for unmanned helicopter based on new approximation-free control
Authors: Jiang Haixiang , Yang Hao , Cen Jian , Gou Xinpan , Chen Yuji
Published: November 2024

This article introduces an enhanced non-approximated control technique for the pitch and altitude control systems of unmanned helicopters. It takes into account unpredictable external disturbances and system dynamics. The integration of prescribed performance control into unmanned helicopter systems significantly improves the transient and steady-state response capabilities. This approach avoids the computational complexities often associated with neural networks and fuzzy control methods. By avoiding the need for function approximation, which can introduce inaccuracies and computational overhead, the controller design process is streamlined. This method’s simplicity and ability to handle unknown disturbances make it highly suitable for real-world implementation, where robustness and efficiency are paramount. Finally, simulations are conducted to showcase the improved transient and steady-state response capabilities achieved by the proposed approach.
The angular distribution of characteristic parameters in eccentric magnetically insulated transmission lines
Authors: Liu Laqun , Wang Haiyang , Wang Huihui , Liu Dagang
Published: November 2024

In pulse power modules designed with linear transformer driver (LTD) and magnetically insulated inductive voltage adder (MIVA) technologies, the phenomenon of electrode eccentricity in long-distance magnetically insulated transmission lines (MITLs) cannot be overlooked due to its impact on pulse power transmission. The paper conducts a theoretical analysis of the distribution of electromagnetic fields, vacuum impedance, and characteristic parameters such as self-limited flow in eccentric MITLs with respect to the angular direction. Additionally, it constructs an eccentric MITL model to validate the theoretical findings.
Dark gap solitons in bichromatic optical superlattices under cubic–quintic nonlinearities
Authors: Chen Junbo , Mihalache Dumitru , Belić Milivoj R. , Shi Jincheng , Zhu Danfeng , Deng Dingnan , Qiu Shaobin , Liao Riwei , Zhu Xing , Zeng Liangwei
Published: November 2024

We demonstrate the existence of two types of dark gap solitary waves—the dark gap solitons and the dark gap soliton clusters—in Bose–Einstein condensates trapped in a bichromatic optical superlattice with cubic–quintic nonlinearities. The background of these dark soliton families is different from the one in a common monochromatic linear lattice; namely, the background in our model is composed of two types of Gaussian-like pulses, whereas in the monochromatic linear lattice, it is composed of only one type of Gaussian-like pulses. Such a special background of dark soliton families is convenient for the manipulation of solitons by the parameters of bichromatic and chemical potentials. The dark soliton families in the first, second, and third bandgap in our model are studied. Their stability is assessed by the linear-stability analysis, and stable as well as unstable propagation of these gap solitons are displayed. The profiles, stability, and perturbed evolution of both types of dark soliton families are distinctly presented in this work.
The encounter of English and Chinese lexicographical traditions
Authors: Li Rui
Published: November 2024

The publication of Wilhelm Lobscheid’s (1822–1893) English and Chinese Dictionary, with the Punti and
Mandarin Pronunciation (1866–1869) marked a turning point in the history
of English-Chinese lexicography. This article traces the genealogy of Lobscheid’s English and Chinese Dictionary
by examining its multiple sources and discusses how the lexicographical tradition of English-Chinese dictionaries was built on
previous dictionaries in the East and the West.
Application of the hybrid integration displacement algorithm based on CEEMDAN and wavelet threshold denoising in vibration screening equipment
Authors: Zhou Jiacheng , Wu Zhi , Duan Zhongwei , Zhang Libin , Liu Fang , Wang Zhen , Zhao Guochao , Hu Chao
Published: November 2024

Vibration screening equipment has an extensive application profile in material screening, in which the displacement parameters can reveal the motion state of the material and affect the screening efficiency. These displacement parameters can be obtained by integrating the acceleration signal of the equipment. In this paper, to prevent the noise in the acceleration signal from further amplifying its negative effects on the subsequent integration, the acceleration signal is preprocessed by the complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and wavelet threshold denoising. Besides, a hybrid integration displacement algorithm is utilized to mitigate the influence of integration errors. The consistent results between simulation and platform experiments demonstrate that CEEMDAN in combination with wavelet threshold denoising can effectively remove noise while retaining the main frequency signal. In addition, the displacement signal obtained by the hybrid integration algorithm proposed in this paper is closer to the original displacement signal. Compared with the 2nd time-domain integration, the 2nd frequency-domain integration, and the empirical mode decomposition integration methods, the integration method proposed in this paper achieves a smaller peak error, mean absolute error, and root mean square error. The experimental results corroborate the superiority of this method in the application of vibration screening equipment.
Dynamic modeling and analysis of brucellosis on metapopulation network: Heilongjiang as cases
Authors: Pei 裴 Xin 鑫 , Wu 武 Xuan-Li 绚丽 , Pei 裴 Pei 沛 , Li 李 Ming-Tao 明涛 , Zhang 张 Juan 娟 , Zhan 詹 Xiu-Xiu 秀秀
Published: November 2024

Livestock transportation is a key factor that contributes to the spatial spread of brucellosis. To analyze the impact of sheep transportation on brucellosis transmission, we develop a human–sheep coupled brucellosis model within a metapopulation network framework. Theoretically, we examine the positively invariant set, the basic reproduction number, the existence, uniqueness, and stability of disease-free equilibrium and the existence of the endemic equilibrium of the model. For practical application, using Heilongjiang province as a case study, we simulate brucellosis transmission across 12 cities based on data using three network types: the BA network, the ER network, and homogeneous mixing network. The simulation results indicate that the network’s average degree plays a role in the spread of brucellosis. For BA and ER networks, the basic reproduction number and cumulative incidence of brucellosis stabilize when the network’s average degree reaches 4 or 5. In contrast, sheep transport in a homogeneous mixing network accelerates the cross-regional spread of brucellosis, whereas transportation in a BA network helps to control it effectively. Furthermore, the findings suggest that the movement of sheep is not always detrimental to controlling the spread of brucellosis. For cities with smaller sheep populations, such as Shuangyashan and Qitaihe, increasing the transport of sheep outward amplifies the spatial spread of the disease. In contrast, in cities with larger sheep populations, such as Qiqihar, Daqing, and Suihua, moderate sheep outflow can help reduce the spread. In addition, cities with large livestock populations play a dominant role in the overall transmission dynamics, underscoring the need for stricter supervision in these areas.
Time and its arrow from quantum geometrodynamics?
Authors: Kiefer Claus , Chataignier Leonardo , Tyagi Mritunjay
Published: November 2024

We discuss how quantum geometrodynamics, a conservative approach to quantum gravity, might explain the emergence of classical spacetime and, with it, the emergence of classical time and its arrow from the universal quantum state. This follows from a particular but reasonable choice of boundary condition motivated by the structure of the Hamiltonian of the theory. This condition can also be seen as defining a quantum version of Penrose’s Weyl curvature hypothesis. We comment on the relation of this picture to the ‘past hypothesis’ and the different observed arrows of time, and we consider how quantum geometrodynamics could serve as a unifying and more fundamental framework to explain these observations.
Intertwined Quantum Phase Transitions in Bose and Bose-Fermi Systems
Authors: Leviatan A.
Published: November 2024

Pronounced structural changes within individual configurations (Type I QPT), superimposed on an abrupt crossing of these configurations (Type II QPT), define the notion of intertwined quantum phase transitions (QPTs). We discuss and present evidence for such a scenario in finite Bose and Bose-Fermi systems. The analysis is based on algebraic models with explicit configuration mixing, where the two types of QPTs describe shape-phase transitions in-between different dynamical symmetries and shape-coexistence with crossing.
Theoretical studies on anharmonic effect and reaction mechanism of reaction CMP+OH
Authors: Luo Lei , Che Li , Xia Wenwen , Yao Li
Published: November 2024

The reaction rate constants between 3-chloro-2-methylpropene (CMP) and OH radical were calculated utilizing the Yao-Lin (YL) method, which concluded harmonic and anharmonic values. In this paper, the anharmonic effect and reaction mechanism of the title reaction and its subsequent reactions were supplied with a detailed analysis. In the CMP+OH reaction, there are two reaction complexes, eight intermediate complexes, nine transition states, and seven products. The optimizations and frequencies of all molecular configurations were calculated at the M06-2X/6-311++G(2d,p) level, and the single-point energies of them were more accurately calculated at the CCSD(T)/6-311++G(2d,p) level. Five main reaction pathways were determined by calculation, including two OH radical addition reactions and three hydrogen atom abstraction reactions. The obtained data show that the values of rate constant increase with the increasing calculation temperature and energy, whether they are harmonic or anharmonic. Furthermore, the kinetic parameters of the CMP+OH reaction and its subsequent reaction steps containing anharmonic effect were fitted. From a series of results, it can be seen that the anharmonic effect in this reaction cannot be simply ignored, and these results can provide theoretical reference for the related research of chemical reaction between CMP and OH radical.
Research on dynamic behaviour of a co-sintered steel-tungsten alloy material
Authors: Ke Ming , Fan Ruyu , Qian Bingwen , Hu Yutao , Wang Changli , Yao Hang , Li Xian , Zhou Gang
Published: November 2024

The newly proposed co-sintering method was used to fabricate reliably connected steel-tungsten alloy layered material. To study the dynamic mechanical properties of steel and tungsten alloy made by co-sintering conditions and interaction between the two matrices of the co-sintered steel-tungsten alloy material, intensive experiments were conducted by the SHPB technique. Experimental results show that temperature rise from 298K to 1073K will cause an 80% loss in strength of the sintered steel, and 50% in tungsten alloy. Strain rates hardening is less prominent, with 18% increase in strength for sintered steel and 15% for tungsten alloy, from 1000/s to 5000/s. The sintered steel shows considerable ductility with high strain rates. However, the tungsten alloy shows great plasticity up to 5000/s at room temperature, thus contributing to the intact of the sintered steel in the bi-layered samples. Engineering applications of co-sintered material should take into account such results. Furthermore, to help numerical analysis of the co-sintered material, a reasonable treatment of the interface of co-sintered structures with incorporation of the dynamic compression behaviour of the bi-layered samples was suggested, but requires further exploration. Even though the experimental data was fitted by altering the meaning of the dimensionless temperature in the Johnson-Cook constitutive model, the reason to the shit between the experimental data and the fitted curves by dimensionless temperature should also be further studied.
The mophology control of hollow tubular cobalt-manganese spinel toward catalytic oxidation of toluene
Authors: Liu Chengchao , Deng Jian , Zheng Yongtao , Wei Siyu , Wang Chunhao , Peng Shanbi
Published: November 2024

In today’s context, the production of nanomaterials with different morphologies is a crucial concern, holding significant importance for catalytic efficiency and real-world usage. In this study, hollow tubular cobalt-manganese spinel prepared by electrospinning technology was used for the catalytic oxidation process of toluene. The lower calcination temperature (single phase) has lower crystallinity, and can provide better catalytic activity, where the sample calcined at 600°C can reach 90% toluene conversion rate with 1000 ppm toluene concentration at 310°C. This study provides a new understanding of the effect of spinel oxide morphology control on the oxidation ability of toluene, and provides a new structural control method for improving the oxidation ability of VOCs.
A Study on the influence of indenter shape for small punch test of non-metallic materials
Authors: Tang Tingting , Xu Lei , Zhao Bo , Wang Lixian , Dai Qiang , Li Ningning
Published: November 2024

Small punch test (SPT) is a type of advanced method for material mechanical property obtain with small-invasive test, which has a good application prospect for judging the mechanical properties of materials at the local position of service components. However, at present, there is a lack of data and engineering basis for the applicability of the two commonly used ball shaped and hemisphere shaped indenters of the SPT method to flexible non-metallic materials, resulting in the lack of universal adaptability standards for the SPT method of non-metallic materials, which is one of the core shackles of the current engineering application of this method. Therefore, based on the results of the traditional uniaxial tensile test, the SPT of polyamide (PA) was carried out by using two shapes of indenters, ball shaped and hemisphere shaped indenter, and the differences between material deformation and fracture caused by the two shapes of indenters were analyzed by the methods of material mechanical properties, macro and micro fracture morphology and numerical simulation. The experimental results show that the top of the indenter has obvious friction with the material during the small punch test, and the maximum deformation position of the material occurs at the diameter of the indenter rounding. Due to the viscoelastic characteristics of high flexibility and large deformation of PA, the shaped part of the indenter is bonded due to plastic deformation rebound during the fracture process. For the spherical indenter, the maximum deformation of the material can wrap the gap formed between the spherical indenter and the punch platform, which will cause the maximum deformation position of the specimen to change during continuous loading, which will affect the authenticity of the data. The maximum deformation position of the hemisphere shaped indenter remains stable, which has a more accurate positioning for evaluating the performance of the material. The test results screen out the SPT indenter shape suitable for flexible non-metallic materials, which provides theoretical guidance and basis for the formulation of SPT test method standards.
Study on mechanical properties of natural rubber and influencing factors of heat generation under compression
Authors: Bi Honghua , Wang Xiaotian , Liu Jincai , Wang Wenfei
Published: November 2024

The effects of different curing systems and fillers on mechanical properties and fatigue heat production of natural rubber were studied by adjusting the sulfur promotion ratio and the type and amount of carbon black in the curing formula. The results show that the natural rubber vulcanized by CV system has the characteristics of high strength and low loss, but the heat yield is still 18.6%. Although large particle size carbon black N770 is not dominant in mechanical properties, it can show excellent effect of reducing fatigue heat production, only 11.3%, which will have certain guiding significance for the design of low heat generation rubber materials for vibration damping components.
“SAVE”—Shock-Assisted Viable Extraction: A Minimally Manipulative Method of Processing Regenerative Cells for Clinical Use
Authors: Del Vecchio Daniel , Vranis Neil , Alevrogianni Korina , Theodorou Spero
Published: November 2024

Background

Extraction of adipose-derived stem cells (ASCs) from the stromal vascular fraction (SVF) has gained significant attention lately in the realm of regenerative medicine. However, finding highly efficient methods of extraction that also comply with the US regulations has prevented widespread clinical use.

Objectives

The objective of this study was to evaluate a novel ASC extraction device to quantify viable ASC extraction and processing efficiency.

Methods

SVF extracted from abdominal fat samples and processed using a novel shock-assisted viable extraction (SAVE) device was tested for stem-cell count and viability. Additionally, time required for processing was recorded.

Results

Twelve adipose samples were utilized for this study. After a mean time of 3 min, cell count yield ranged of 47,400 to 189,400 of viable regenerative cells per cc, with an average of 122,464 viable regenerative cells per cc.

Conclusions

SAVE is a novel fat-processing technique with high stem-cell extraction that shows promise from a regulatory, yield, time efficiency, and cost perspective.

Level of Evidence: 5 (Therapeutic)
Facilitating phenotyping from clinical texts: the medkit library
Authors: Neuraz Antoine , Vaillant Ghislain , Arias Camila , Birot Olivier , Huynh Kim-Tam , Fabacher Thibaut , Rogier Alice , Garcelon Nicolas , Lerner Ivan , Rance Bastien , Coulet Adrien
Published: November 2024

Phenotyping consists in applying algorithms to identify individuals associated with a specific, potentially complex, trait or condition, typically out of a collection of Electronic Health Records (EHRs). Because a lot of the clinical information of EHRs are lying in texts, phenotyping from text takes an important role in studies that rely on the secondary use of EHRs. However, the heterogeneity and highly specialized aspect of both the content and form of clinical texts makes this task particularly tedious, and is the source of time and cost constraints in observational studies.

 

To facilitate the development, evaluation and reproducibility of phenotyping pipelines, we developed an open-source Python library named medkit. It enables composing data processing pipelines made of easy-to-reuse software bricks, named medkit operations. In addition to the core of the library, we share the operations and pipelines we already developed and invite the phenotyping community for their reuse and enrichment.

Availability and implementation

medkit is available at https://github.com/medkit-lib/medkit.
Beyond exclusion: revisiting exploitative abuses in digital platform markets
Authors: Balasingham Baskaran , D’Amico Alessia S
Published: November 2024

With the rapid expansion of digital platforms, concerns regarding exploitative practices have gained prominence, necessitating a closer examination of the possibilities available to competition authorities to address them. In light of the higher error costs of enforcement compared to exclusionary abuses, scholars have come up with structured approaches to identify in which situations exploitative abuse actions are justified. However, these approaches are mostly geared towards excessive prices and have not been adapted to digital platform markets, where customers and consumers are more likely to encounter unfair trading conditions. The aim of this article is to examine the extent to which the structured approaches developed in the literature are applicable to cases of unfair trading conditions by digital platforms. In order to do so, we first review the literature to establish the most widely supported conditions under which intervening against excessive price is justified. We identify the following conditions: (i) the presence of high and non-transitory barriers to entry; (ii) an enhanced dominant position; (iii) the absence of sector-specific regulation; and (iv) enhanced consumer harm. We then apply those conditions to exploitative abuse cases in digital platform markets and propose adjustments to ensure they are appropriate to guide competition authorities’ intervention.
Three-dimensional numerical calculation and case application of IP five-directional well logging
Authors: Zhao Rongchun , Lv Yuzeng , Zhang Zhi , Wei Liuye , Hou Xiying
Published: November 2024

Conventional well logging can effectively detect the vertical distribution range of ore bodies near the well by placing detectors in the well. However, its detection capability for the horizontal extension of ore bodies is limited. Therefore, starting from the differential equations satisfied by the point source in three-dimensional structures, this paper deduces the variational problem satisfied by the total potential under three-dimensional complex conditions. By focusing on well logging, tetrahedral cross-grid partitioning technology is employed to achieve high-precision three-dimensional finite element forward modeling. Simulations are carried out for different forms of ore bodies using the induced polarization five-direction observation method, considering the presence of ore bodies near the well and the case where the measurement well passes through the ore body. The paper analyzes and summarizes the induced polarization anomaly patterns formed by ore bodies with low resistance and high polarization in different horizontal extension directions under induced polarization five-direction logging with power supply measurements from different directions. Based on this, a human–computer interaction system is constructed to perform forward fitting and inversion interpretation of the measured induced polarization data, resulting in a good application effect.
The causal arrows from genotype, environment, and management to plant phenotype are double headed
Authors: Sadras Victor O , Hayman Peter T
Published: November 2024

Cause-and-effect arrows are drawn from genotype (G), environment (E), and agronomic management (M) to the plant phenotype in crop stands in a useful but incomplete framework that informs research questions, experimental design, statistical analysis, data interpretation, modelling, and breeding and agronomic applications. Here we focus on the overlooked bidirectionality of these arrows. The phenotype-to-genotype arrow includes increased mutation rates in stressed phenotypes, relative to basal rates. From a developmental viewpoint, the phenotype modulates gene expression, returning multiple cellular phenotypes with a common genome. The phenotype-to-environment arrow is captured in the process of niche construction, which spans from persistent and global to transient and local. Research on crop rotations recognizes the influence of the phenotype on the environment but is divorced from niche construction theory. The phenotype-to-management arrow involves, for example, a diseased crop that may trigger fungicide treatment. Making explicit the bidirectionality of the arrows in the G×E×M framework contributes to narrowing the gap between data-driven technologies and integrative theory, and is an invitation to think cautiously of the internal teleonomy of plants in contrast to the view of the phenotype as the passive end of the arrows in the current framework.
Adverse Events Reported During Weekly Isoniazid-Rifapentine (3HP) Tuberculosis Preventive Treatment Among People With Human Immunodeficiency Virus in Uganda
Authors: Kadota Jillian L , Musinguzi Allan , Aschmann Hélène E , Akello Lydia , Welishe Fred , Nakimuli Jane , Berger Christopher A , Kiwanuka Noah , Phillips Patrick P J , Katamba Achilles , Dowdy David W , Cattamanchi Adithya , Semitala Fred C
Published: November 2024

Background

Short-course tuberculosis (TB) prevention regimens, including 12 weeks of isoniazid and rifapentine (3HP), are increasingly used in high-TB-burden countries. Despite established safety and tolerability in efficacy trials, 3HP-related adverse events (AEs) could differ in routine settings. Real-world data on AE type, frequency, and timing are crucial for health systems considering 3HP programmatic scale-up.

Methods

We reviewed AEs among people with human immunodeficiency virus (HIV) participating in a pragmatic implementation trial of facilitated 3HP taken by directly observed therapy (DOT) or self-administered therapy (SAT) in Kampala, Uganda, and classified them using the Common Terminology Criteria for Adverse Events. We assessed AE timing and summarized related clinical actions including laboratory tests, diagnoses made, medications prescribed, and treatment interruptions.

Results

Among 1655 people with HIV treated between July 2020 and September 2022, 270 (16.3%) reported 451 events; main issues included general (7%), nervous system (6%), musculoskeletal (5%), gastrointestinal (5%), and dermatologic (3%) disorders. Most (61%) occurred within 6 weeks of initiating 3HP. Among those with events, 211 (78%) required further clinician evaluation, 202 (75%) required laboratory testing, 102 (38%) had medications prescribed, 40 (15%) had treatment paused, and 14 (5%) discontinued 3HP. Women, those multidimensionally impoverished, and DOT recipients were more likely to report an AE. SAT users and later enrollees were more likely to have 3HP interrupted or stopped due to an AE.

Conclusions

In a routine setting, 3HP was safe, with 16% of people with HIV reporting AEs and only 3% requiring temporary or permanent treatment interruption. These findings support 3HP expansion in routine HIV/AIDS care settings for TB prevention.

Clinical Trials Registration. NCT03934931.
The Riddle of the Good Faith Purchaser
Authors: Crawford Michael J R
Published: November 2024

A purchaser unwittingly buys stolen goods. The owner from whom they were stolen demands their return. The purchaser refuses. How should the law resolve their dispute? This article argues that the law’s primary objective in resolving disputes between owners and good faith purchasers should not be to achieve ‘justice’ between the parties but to disincentivise theft. With some categories of goods, it is difficult to see how the legal attribution of liability can achieve this end. However, where goods are amenable to registration, the rules of good faith purchase can discourage theft by conditioning an owner’s success over a good faith purchaser on the fact of prior registration. In the absence of a register, there seems little to choose between the parties. However, because the favoured party will frequently be a monopolist, the danger of holdouts warrants employing innovations from auction theory, the effect of which is to force the parties to reveal otherwise private information about their subjective valuations of the disputed goods.
Metagenomics data of a historical Ophiovirus citri isolate infecting citrus in Australia and its findings for RT-qPCR detection
Authors: Donovan Nerida J. , Maina Solomon , Englezou Anna , Chambers Grant A.
Published: November 2024

Ophiovirus citri is a graft-transmissible citrus virus and is the presumed causal agent of citrus psorosis disease. Australian historical isolate CL222 induces symptoms typically associated with psorosis of oakleaf patterns and leaf flecking on inoculated Symons sweet orange biological indicator plants. Genomic analysis of CL222 revealed a nucleotide match of 99.8-99.9% to Chinese CPsV genomes (CH3 isolate; GenBank accessions MG673944, MG673945 and MG673946). The detection of a single nucleotide variation in the coat protein gene of the Australian isolate CL222 led to the design of an improved RT-qPCR probe to enable virus detection of Australian and other isolates. O. citri is rarely detected in field trees in Australia, likely due to the widespread use of pathogen-free propagation material.
TAD‐dependent sub‐TAD is required for enhancer–promoter interaction enabling the β‐globin transcription
Authors: Lee Dasoul , Kang Jin , Kim AeRi
Published: November 2024

Topologically associating domains (TADs) are chromatin domains in the eukaryotic genome. TADs often comprise several sub‐TADs. The boundaries of TADs and sub‐TADs are enriched in CTCF, an architectural protein. Deletion of CTCF‐binding motifs at one boundary disrupts the domains, often resulting in a transcriptional decrease in genes inside the domains. However, it is not clear how TAD and sub‐TAD affect each other in the domain formation. Unaffected gene transcription was observed in the β‐globin locus when one boundary of TAD or sub‐TAD was destroyed. Here, we disrupted β‐globin TAD and sub‐TAD by deleting CTCF motifs at both boundaries in MEL/ch11 cells. Disruption of TAD impaired sub‐TAD, but sub‐TAD disruption did not affect TAD. Both TAD and sub‐TAD disruption compromised the β‐globin transcription, accompanied by the loss of enhancer–promoter interactions. However, histone H3 occupancy and H3K27ac were largely maintained across the β‐globin locus. Genome‐wide analysis showed that putative enhancer–promoter interactions and gene transcription were decreased by the disruption of CTCF‐mediated topological domains in neural progenitor cells. Collectively, our results indicate that there is unequal relationship between TAD and sub‐TAD formation. TAD is likely not sufficient for gene transcription, and, therefore, sub‐TAD appears to be required. TAD‐dependently formed sub‐TADs are considered to provide chromatin environments for enhancer–promoter interactions enabling gene transcription.