bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced single-phase heat transfer performance via vortex secondary flow in hypervapotron configuration
Authors: Lim Ji Hwan , Park Minkyu 
Published: December 2021

Abstract
As the hypervapotron (HV) heat sink is used to cool many areas inside the fusion tokamak, it is essential to understand its heat transfer performance to calculate the thermal efficiency of the power generation system. Therefore, in this study, the single-phase (SP) heat transfer performance of HV heat sink was evaluated through sub-cooled flow boiling experiments under one-side high-heat load conditions. When vapor is generated inside the heat sink, flow instability and a potential risk of reaching the critical heat flux are created. Therefore, in commercial power plants, cooling systems tend to operate in the SP regime. System parameters that can be adjusted in the power generation system include the system pressure, mass flow rate, and subcooling, and the effect of these three parameters on the heat transfer performance in the SP regime was analyzed. It was experimentally observed that the mass flow rate was the most influential variable. The prediction performance of the SP forced convection heat transfer correlations of the existing conventiaonl channel were evaluated. The results revealed that they tended to under-predict the heat transfer performance of the HV heat sink. In addition, the same trends were found when the forced convection heat transfer correlation of the curved channel was evaluated. The reasons for the former and the latter are that the heat transfer enhancement effect by the vortex flow occurring between the fins of the HV heat sink is not reflected in the correlations, and the vortex effect of the HV heat sink is not expressed as a variable. Therefore, a new vortex forced convection heat transfer correlation was developed through the newly defined Dean number of the HV heat sink. The developed correlation recorded an average error rate of 0.48%.
Theoretical study of electronic properties and chemical stability of cubic phase zirconia nanowires
Authors: Cuevas F J L , Courel Piedrahita M , Feddi E , Rentería T V M , Ojeda M M L , Velásquez O C , Mowbray D J , Ojeda M M 
Published: December 2021

Abstract
Zirconia bulk is one of the most studied materials around the world due to different properties such as a high melting temperature, biocompatibility and high thermal expansion, among many others. However, there is little experimental research about Zirconia nanowires and until now there are few theoretical papers on the subject. In this work, Density Functional Theory (DFT) calculations on bare ZrO2 nanowires with diameter variation were performed. In order to get the more accurate parameters for calculation on nanowires, we employed the Murnaghan equation of state in a perfect cubic crystal of ZrO2 (c-ZrO2) and we compared the results obtained with some experimental data as well as the lattice parameter and the bulk modulus. The nanowires were grown along the [1 1 1] direction with five different diameters. All calculations were carried out by DFT implemented in SIESTA code. According to our results, the functional PBE of the Generalized Gradient Approximation (GGA-PBE) is the more accurate functional for describing the E
xc
on ZrO2. The calculation of formation and surface energies shows that these nanowires are chemically stable. Furthermore, nanowires larger than 8.78 Å present a direct band gap. These results indicate the possibility of applying ZrO2 nanowires in the optoelectronic field.
Nonlinear structures: soliton, shocklike and explosive waves in quantum semiconductor plasma
Authors: Al-Yousef Haifa A 
Published: December 2021

Abstract
The properties and conditions for the appearance of some nonlinear waves in a three-dimensional semiconductor plasma are discussed, by studying the described plasma fluid system with quantum gradient forces and degraded pressures. Our analytical procedure is built on the reductive perturbation theory to obtain the Kadomtsev-Petvashvili equation for the fluid model and solving it using the direct integration method and the Bäcklund transform. Through different solution methods we got different nonlinear solutions describing different pulse profiles such as soliton, kink and explosive pulses. This model can be used to identify the potential disturbances in a semiconductor plasma.
A mechanism for spin electron acoustic soliton observed in a spin-polarized nanosized electron-hole plasma
Authors: Afify M S , Iqbal Z , Murtza G 
Published: December 2021

Abstract
The formation and the characteristics of spin electron acoustic (SEA) soliton in a beam interacting spin-polarized electron-hole plasma are investigated. These wavepackets are supposed to be the source of heating during the excitation process. We have used the separate spin evolution-quantum hydrodynamic (SSE-QHD) model along with Maxwell equations and derived the Korteweg–de Vries (KdV) equation by using the reductive perturbation method (RPM). We note that the larger values of beam density and spin polarization can change the soliton nature from rarefactive to compressive. Our findings may be important to understand the characteristics of localized spin-dependent nonlinear waves in nanosized semiconductor devices.
Nonlinear oscillations in a constant gravitational field
Authors: Kontomaris S V , Malamou A 
Published: December 2021

Abstract
Exploring non-linear oscillations is a challenging task since the related differential equations cannot be directly solved in terms of elementary functions. Thus, complicated mathematical or numerical methods are usually employed to find accurate or approximate expressions that describe the behavior of the system with respect to time. In this paper, the vertical oscillations of an object under the influence of its weight and an opposite force with magnitude F = cyn, where n > 0 are being explored. Accurate and approximate simple solutions regarding the object’s position with respect to time are presented and the dependence of the oscillation’s period from the oscillation’s range of displacements and the exponent n is revealed. In addition, the special case in which n = 3/2 (which describes the oscillation of a rigid sphere on an elastic half space) is also highlighted. Lastly, it is shown that similar cases (such as the case of a force with magnitude F = kx + λ×2) can be also treated using the same approach.
Cosmology at high redshift — a probe of fundamental physics
Authors: Sailer Noah , Castorina Emanuele , Ferraro Simone , White Martin 
Published: December 2021

Abstract
An observational program focused on the high redshift (2<z<6) Universe has the opportunity to dramatically improve over upcoming LSS and CMB surveys on measurements of both the standard cosmological model and its extensions. Using a Fisher matrix formalism that builds upon recent advances in Lagrangian perturbation theory, we forecast constraints for future spectroscopic and 21-cm surveys on the standard cosmological model, curvature, neutrino mass, relativistic species, primordial features, primordial non-Gaussianity, dynamical dark energy, and gravitational slip. We compare these constraints with those achievable by current or near-future surveys such as DESI and Euclid, all under the same forecasting formalism, and compare our formalism with traditional linear methods. Our Python code FishLSS — used to calculate the Fisher information of the full shape power spectrum, CMB lensing, the cross-correlation of CMB lensing with galaxies, and combinations thereof — is publicly available.
Unlocking the synergy between CMB spectral distortions and anisotropies
Authors: Fu Hao , Lucca Matteo , Galli Silvia , Battistelli Elia S. , Hooper Deanna C. , Lesgourgues Julien , Schöneberg Nils 
Published: December 2021

Abstract
Measurements of the cosmic microwave background (CMB) spectral distortions (SDs) will open a new window on the very early universe, providing new information complementary to that gathered from CMB temperature and polarization anisotropies. In this paper, we study their synergy as a function of the characteristics of the considered experiments. In particular, we examine a wide range of sensitivities for possible SD measurements, spanning from FIRAS up to noise levels 1000 times better than PIXIE, and study their constraining power when combined with current or future CMB anisotropy experiments such as Planck or LiteBIRD plus CMB-S4. We consider a number of different cosmological models such as the ΛCDM, as well as its extensions with the running of the scalar spectral index, the decay or the annihilation of dark matter (DM) particles. While upcoming CMB anisotropy experiments will be able to decrease the uncertainties on inflationary parameters such as As and ns by about a factor 2 in the ΛCDM case, we find that an SD experiment 100 times more sensitive than PIXIE (comparable to the proposed Super-PIXIE satellite) could potentially further contribute to constrain these parameters. This is even more significant in the case of the running of the scalar spectral index. Furthermore, as expected, constraints on DM particles decaying at redshifts probed by SDs will improve by orders of magnitude even with an experiment 10 times worse than PIXIE as compared to CMB anisotropies or Big Bang Nucleosynthesis bounds. On the contrary, DM annihilation constraints will not significantly improve over CMB anisotropy measurements. Finally, we forecast the constraints obtainable with sensitivities achievable either from the ground or from a balloon.
Performance of passive decoy-state quantum key distribution with mismatched local detectors
Authors: Yu Kai , Zhang Chun-Hui , Zhou Xing-Yu , Wang Qin 
Published: December 2021

Abstract
In quantum key distribution (QKD), the passive decoy-state method can simplify the intensity modulation and reduce some of side-channel information leakage and modulation errors. It is usually implemented with a heralded single-photon source. In Wang et al 2016 (Phys. Rev. A 96 032312), a novel passive decoy-state method is proposed by Wang et al, which uses two local detectors to generate more detection events for tightly estimating channel parameters. However, in the original scheme, the two local detectors are assumed to be identical, including the same detection efficiency and dark count rate, which is often not satisfied in the realistic experiment. In this paper, we construct a model for this passive decoy-state QKD scheme with two mismatched detectors and explore the effect on QKD performance with certain parameters. We also take the finite-size effect into consideration, showing the performance with statistical fluctuations. The results show that the efficiencies of local detectors affect the key rate more obviously than dark count rates.
Effect of atmospheric turbulence on orbital angular momentum entangled state
Authors: Yan Xiang , Zhang Peng-Fei , Fan Cheng-Yu , Zhang Jing-Hui 
Published: December 2021

Abstract
The entangled orbital angular momentum (OAM) photons propagating across a weakly turbulent atmosphere are investigated. Here, the paper uses the single-phase screen model based on the Kolmogorov theory of turbulence, and focuses on the influence of the backward scattering on OAM evolution. The results indicate that backward scattering plays an important role in the analysis of OAM entanglement evolution in the turbulent atmosphere. It cannot be negligible especially for higher-order OAM mode. Moreover, when OAM mode is greater than 4, entangled photon pairs composed of higher OAM modes are not more robust in turbulence within the weak scintillation regime. These results will be useful in future investigations of OAM-based optical wave propagation through turbulent atmosphere.
Motor imagery practice and feedback effects on functional connectivity
Authors: Stefano Filho Carlos Alberto , Attux Romis , Castellano Gabriela 
Published: December 2021

Abstract

Objective. The use of motor imagery (MI) in motor rehabilitation protocols has been increasingly investigated as a potential technique for enhancing traditional treatments, yielding better clinical outcomes. However, since MI performance can be challenging, practice is usually required. This demands appropriate training, actively engaging the MI-related brain areas, consequently enabling the user to properly benefit from it. The role of feedback is central for MI practice. Yet, assessing which underlying neural changes are feedback-specific or purely due to MI practice is still a challenging effort, mainly due to the difficulty in isolating their contributions. In this work, we aimed to assess functional connectivity (FC) changes following MI practice that are either extrinsic or specific to feedback. Approach. To achieve this, we investigated FC, using graph theory, in electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data, during MI performance and at resting-state (rs), respectively. Thirty healthy subjects were divided into three groups, receiving no feedback (control), ‘false’ feedback (sham) or actual neurofeedback (active). Participants underwent 12–13 hands-MI EEG sessions and pre- and post-MI training fMRI exams. Main results. Following MI practice, control participants presented significant increases in degree and in eigenvector centrality for occipital nodes at rs-fMRI scans, whereas sham-feedback produced similar effects, but to a lesser extent. Therefore, MI practice, by itself, seems to stimulate visual information processing mechanisms that become apparent during basal brain activity. Additionally, only the active group displayed decreases in inter-subject FC patterns, both during MI performance and at rs-fMRI. Significance. Hence, actual neurofeedback impacted FC by disrupting common inter-subject patterns, suggesting that subject-specific neural plasticity mechanisms become important. Future studies should consider this when designing experimental NFBT protocols and analyses.
Reduced health burden and economic benefits of cleaner fuel usage from household energy consumption across rural and urban China
Authors: Lu Chenxi , Zhang Shaohui , Tan Chang , Li Yun , Liu Zhu , Morrissey Karyn , Adger W Neil , Sun Taochun , Yin Hao , Guo Jiahong 
Published: December 2021

Abstract
Energy consumption in the residential sector is increasing rapidly in China. This study applies an integrated assessment model to investigate the adverse impacts of household energy consumption by various fuel types across rural and urban areas on age- and sex-specific premature deaths associated with PM2.5 pollution at provincial levels for 2015. We further estimate the economic and health co-benefits of a switch from solid fuels to electricity within households. We find that energy consumed by Chinese urban households is nearly 1.6 times than that of rural households. However, premature deaths due to household energy usage is 1.1 times higher in rural areas compared to urban areas due to direct use of coal for heating in rural households. The majority of household consumption-related premature deaths are predominately in the Southern area of China due to the population size and aging population. By replacing coal and biomass with electricity, this paper estimates economic benefits equal to 0.09% (95% CI: 0.08%–0.1%) GDP for rural areas and 0.006% (0.005%–0.007%) of GDP for urban areas of China. The results suggest that mitigation measures such as the promotion and subsidization of cleaner fuels, modern stove within rural households would yield these potential significant economic benefits.
Physical modeling of water-retention capacity of soils
Authors: Moiseev K , Terleev V , Turutina T , Surinsky D 
Published: December 2021

Abstract
The function of the water-retention capacity of the soil is necessary, for example, when calculating irrigation norms in irrigation agriculture. Various mathematical models are used to approximate the water-retention capacity, which have a number of disadvantages inherent in these models. For example, the absence of physically adequate analytical descriptions for the coefficients of a given function. The use of physical fractal models for predicting and calculating the water-retention capacity of soils seems promising. Application of the fractal model Pore-Solid-Fractal is necessary to perform the calculation of desorption curves of water-retention capacity of some types of alpha-humus and texture-differentiated soils of light particle size distribution has been performed. The calculated data for the drying branches of the WRC are compared with the experimental data. The study of statistical differences between samples (data convergence) was carried out using the Mann-Whitney test (U). The empirical values of the U-test are from 17.5 to 20. The critical value of the U-test for a given number of compared data series at a probability level of 0.99 is 8. The critical value of the U-test for a given sample size is less than the calculated one, respectively, the difference between the series of empirical and the calculated data in the sample are not statistically significant. The fractal model allows calculating the water-retention capacity function of soils with high accuracy.
Methods of using non-traditional types of physical exercises when working with pathologies that have arisen under the influence of environmental degradation
Authors: Ryzhkin Nikolay , Ivanova Anna 
Published: December 2021

Abstract
The article presents an experimental method of using game forms of classes aimed at improving the level of physical development of students with poor health and low level of physically fit. We worked with students with excessive weight gain not associated with health abnormalities. The group of students who, as a result of a medical examination, were found to have diseases of the endocrine glands, where excess weight is a concomitant sign of a serious disease did not include in the research. One of the objectives of the study was to identify changes in the students’ state of health and increase interest in classes, activating physical education classes for first-year students with various degrees of disorders of physically fit. The analysis of the impact of the proposed program on students, taking into account the specifics of the faculties and various specialties, will allow us to enrich the curriculum in physical culture. As well as, this will allow us to include in the program of classes non-traditional types of physical exercises while working with special medical groups, taking into account the pedagogical orientation of the faculties of the university.
Study of the properties of the ovarian fluid of the Russian sturgeon (Acipenser gueldenstaedtii Brandt, 1833) during freezing
Authors: Firsova Angelina , Ponomareva Elena , Krasilnikova Aleksandra , Belaya Maria 
Published: December 2021

Abstract
The process of freezing the ovarian fluid of the Russian sturgeon (Acipenser gueldenstaedtii Brandt, 1833) was analyzed. With gradual cooling from 22°C to -196°C at a rate of 10° per minute, the process of freezing, formation and change of ice microparticles was observed. The ovarian liquid was glazed at -5°C and only at -70°. With the microparticles of ice began to form. From that moment, up to the temperature of liquid nitrogen (-196°C), the microparticles were crushed into smaller ones. The high content of intracellular water in the ovarian fluid of female Russian sturgeon contributes to the formation of the bulk of microparticles of ice, which is confirmed by their shape. These particles, which have sharp edges, are able to damage the thin shells of eggs during deep freezing.
Trichinosis in the Rostov oblast
Authors: Lipilkina Tatyana , Popov Igor , Lipilkin Pavel , Ermakov Alexey 
Published: December 2021

Abstract
In the Russian Federation, cases of infection with trichinosis in a population of people or animals are annually recorded. Trichinosis is intestinal and tissue helminthiasis of humans and a number of mammals, caused all over the world by nematodes. A person becomes infected with the parasite by eating meat containing live encapsulated Trichinella larvae. Mating takes place in the gastrointestinal tract, fertilized females are introduced into the intestinal mucosa with their anterior thinned ends. The clinical picture of trichinosis is accompanied by the development of myositis, degeneration of muscle fibers, and multiple edema. Deaths are not uncommon due to necrotic ulcerative lesions of the intestine and internal bleeding.
Bioactive materials in the traumatology of small pets
Authors: Krotova O , Bashkatova N , Savenkov K , Sklyarov S , Manjikova A 
Published: December 2021

Abstract
The effect of the biocomposition material was studied on the basis of synthetic hydroxyapatite, collagen and antibiotic for reparative histogenesis of bone tissue during shoulder bone fractures and forearm in dogs and implants for the tissue regeneration of the new generation Xenograft Collagen.It has been established that remodeling of the primary bone corn into the secondary in the region of the fracture in the dogs studied was diverse. During the experiment, it was revealed that a month after the operation on radiographs in the control group of dogs, there was a defect in which the formation of a weak periosal bone corn was observed. Endostal bone corn has not been detected. The most pronounced process proceeded by dogs in experienced groups. In the first experimental defect, a collapan was filled with a drug, and in the second used the implant in the form of the xenograft collagen granules. In animals of the first experienced group, the primary bone-cartilage corn had a more mature and developed character, intermediary and periosal corns were formed.
Application of information technologies in solving environmental problems
Authors: Eskov A V , Kiryushin I I , Medvedev Yu S , Zhuchkova V V 
Published: December 2021

Abstract
The examples of software and hardware solutions used in the Russian Federation, which can be used to monitor the environmental situation in various territories, are given. The possibility of using mathematical models in the fight against environmental problems, in particular, for tracking animal populations, is shown.
Environmental management system and its impact on productivity
Authors: Ushakov D , Cherkasova L , Shatila Kh 
Published: December 2021

Abstract
The environmental aspect is now a significant element in polluting companies’ management choices. The laws defined by the establishment of standards and requirements to guarantee a minimally contaminated environment are applicable to these companies. These standards have encouraged companies to implement environmental management systems. According to these concepts, our research aimed at assessing the improvement in productivity of companies working in the industrial sector by adopting an environment management system. We evaluated productivity by defining and estimating the manufacturing function using a sample consisting of Thailand businesses, and then utilized the panel data to test its effect upon manufacturing companies’ productivity by adopting the environmental management system. The installation of an EMS and productivity have been favourable and significantly correlated