bluuebunny/crossref_metadata_2025_split huggingface dataset:
Host isotope effects on the oxygen local vibrations in CdTe
Authors: Tarhan Enver , Ramdas Anant K 
Published: September 2023

Abstract
Strong absorption peak observed near 350 cm−1 in the infrared spectrum of CdTe is assigned to a localized vibrational mode of 16O impurity atoms at tellurium sites. In this work, we studied the nature of these vibrations in terms of the effect of isotopic mass variations in the nearest neighbor Cd atoms. We showed that Cd atoms with 8 stable natural isotopes of varying abundances cause the observed line shape in the observed localized vibrational absorption peak. To calculate the effect of isotopic mass variations, we used the XY4 molecular model, X being the impurity atom at a host Te atom site and Y’s are various isotopes of the host Cd atoms. Corresponding frequencies of local modes were calculated for each possible combinations of neighboring Cd atoms. For an XY4 molecule with Td symmetry, only the triply degenerate

Γ

5

mode is infrared active. The energies of this mode are higher than those of the others. This mode is possible only when all neigboring Cd atoms are the same isotope. To simulate the absorption data, we used a dynamical matrix approach where a force constant is given for each of the bending and stretching potential energy terms. By diagonalization of the dynamical matrix we were able to fit the calculated spectrum to the data with a proper choice of the bending and stretching force constants. A good agreement with the experiment as well as reported force constants for other impurities in CdTe is obtained.
Broadband and precise reconfiguration of megahertz electromagnetic metamaterials for wireless power transfer
Authors: Zhang Rui , Wang Kaiqi , Wang Xiaole , Luo Xudong , Zhao Chunyu 
Published: September 2023

Abstract
It is a significant challenge to construct reconfigurable electromagnetic metamaterials that can precisely manipulate broadband megahertz electromagnetic waves. Herein, we report a reconfigurable electromagnetic metamaterial (REMM) composed of a two-dimensional periodic array of spiral copper-clad unit cells, each paralleled with a micro-tunable capacitor, which has nearly linear voltage-controlled properties. Moreover, the on-board integrated sample-and-hold modules, linked to all the REMM unit cells, are activated sequentially to perform precise voltage regulation of micro-tunable capacitors for controlling the electromagnetic properties of each unit cell. The experiment results demonstrate that the REMM sample has a maximum frequency adjustment range of 2.1 MHz, ranging from 8.7 MHz to 10.9 MHz with less than 0.1 MHz adjustment step. Furthermore, in a wireless power transfer system, the proposed REMM can achieve the desirable magnetic-field manipulation by precisely adjusting the permeability distribution compared with the traditional metamaterial slab merely capable of full-negative permeability. As a result, the power transfer efficiency (PTE) can be increased from 9.53% to 11.51% (1.69% for the case without the metamaterial slab), and approximately 3.5-fold improvement (from 0.28% to 0.98%) can be achieved when coils are misaligned. This work lays the foundation for the control of electromagnetic waves through using broadband and precise reconfiguration of megahertz electromagnetic metamaterials.
First-principles study of potassium-based novel chalcogenide materials for optoelectronic and thermoelectric devices
Authors: Gul Banat , Khan Muhammad Salman , lfseisi Ahmad A , Ahmad Hijaz 
Published: September 2023

Abstract
The structural, electronic, optical, and thermoelectric natures of potassium-based ternary KAuY (Y = S, Se, and Te) materials are studied by employing density functional theory calculations. The LDA and PBE-GGA approximations were used to properly address the strongly correlated electron complexes. The ground-state energies, cohesive energies, and specifically the computed formation energy calculation predicted their stable nature. The calculated electron-effective mass of KAuTe was lower as compared to KAuS and KAuSe suggesting the presence of non-uniformity in energy bands at the conduction band minimum (CBM). The broader energy band gaps display the existence of firmly covalent bonds. The computed band structures calculation well supports their density of states calculations and validates the semiconductor nature of these materials. Moreover, optical constants such as the two components of the complex dielectric function, energy loss functions, absorption coefficients, reflectivity, and refractive index spectra are calculated and also explained for their potential usage in optoelectronic devices. The vital thermoelectric features are computed that suggest the studied material systems’ potential in the thermoelectric application. Principally, the present work would aid in the advancement of integrated and diverse semiconductors for high technological devices.
S-wave heavy pentaquark production in direct fragmentation of heavy quark
Authors: Moosavi Nejad S Mohammad , Farashahian R 
Published: September 2023

Abstract
Study of exotic hadrons with configurations beyond the naive quark model has attracted a lot of interests in recent years. Due to their complicated configuration many theoretical models have been designed for describing their structure. Understanding the production mechanism of exotic hadrons could be helpful to find out their inner structure and to test the theory of QCD as well. It is well-known that the dominant production mechanism for conventional heavy hadrons with large transverse momentum is fragmentation so as this mechanism could also be extended to heavy pentaquarks production. This work is a first effort to study the direct fragmentation of heavy quarks into ground state heavy pentaquarks in leading order of perturbative QCD. Considering the picture of compact pentaquark states, through the Suzuki approach we will compute the fragmentation function of heavy quarks into S-wave heavy pentaquarks. The production cross section of heavy pentaquarks through pair annihilation will also be estimated at lowest order of perturbative QCD.
Role of O2 and N2 addition on low-reflectance Si surface formation using moderate-pressure (3.3 kPa) hydrogen plasma
Authors: Nomura Toshimitsu , Kakiuchi Hiroaki , Ohmi Hiromasa 
Published: September 2023

Abstract
We prepared ‘black Si’ with Si nanocone structures using a moderate-pressure H2 plasma at 3.3 kPa with a minor air addition. The roles of N2 and O2 as additives in Si-nanocone formation were investigated. Air additives in H2 gas are required to form Si oxynitride micromasks on the surface, and the O2 concentration in the additive modifies the chemical and physical characteristics of the micromasks. When the additive in the H2 gas was only O2, a relatively smooth sample surface or a low-aspect-ratio nanocone structure was formed. In contrast, the N2-only additive of H2 gas resulted in a fine nanopillar structure with a low height. An O2 concentration in the additives of approximately 20% is desirable for black Si fabrication. In addition, the etching rate of the SiO2 film using moderate-pressure H2 plasma was three times higher than that of the SiNx film. In addition, an adequate additive O2 concentration in the H2 gas increased the atomic H density in the plasma. As a result, a Si surface with a very low light reflectance of less than 0.5% in the wavelength range of 380–830 nm was obtained.
Electromagnetic fluctuation and collective modes in relativistic bosonic superfluid in mixed dimensions
Authors: Hsiao Wei-Han 
Published: September 2023

Abstract
In Gaussian approximation, we investigate the marginal electromagnetic fluctuation in models of charged relativistic bosonic superfluids in three and two spatial dimensions at zero temperature. The electromagnetism is modeled by the ordinary Maxwell term and the non-local pseudo-electrodynamics action in these dimensions respectively. We explore the collective excitations in these systems by integrating the superfluid velocity fields. We unveil that different collectives mode dispersions are results of the competition between different characteristic scales of speed and that between short-ranged and long-ranged interactions. In (3+1) dimensions, we derive the roton mode reminiscent of what was discovered in the context of the free relativistic Bose–Einstein condensate as a generalization of the Higgs mode and determine the necessary and sufficient condition for the roton to exist. In (2+1) dimensions, besides solving the dispersion relation for the surface plasmon, we prove there cannot be roton-like excitation in this model as opposed to its (3+1) dimensional counterpart, and additionally derive the asymptotic lines of the dispersion in the limits of long wavelength and short distance. These asymptotic dispersions are supplied with alternative perspective using duality.
Transition from MAR to EIR of deuterium plasma detachment in NAGDIS-II
Authors: Shi Jielin , Kaizawa Hideki , Tanaka Hirohiko , Kajita Shin , Ohno Noriyasu , Ding Hongbin 
Published: September 2023

Abstract
Volumetric plasma recombination in a detached deuterium (D) plasma was experimentally studied in the linear plasma device NAGDIS-II. The radial distributions of the electron temperature (T

e
) and the electron density (n

e
) were measured by upstream and downstream laser Thomson scattering (LTS) systems and D-atom excited states of the Balmer series (n = 3–7) were measured by optical emission spectroscopy (OES). The results indicated that the electron static pressure, particle flux and heat flux present a two-step reduction with an increasing neutral pressure, suggesting that molecule activated recombination (MAR) and electron–ion recombination (EIR) were activated, respectively. The difference in the distributions of the atomic state population densities was observed to be a feature of the transition from the MAR-dominant phase to the EIR-dominant phase. The transition between the two phases had a distinct boundary at T

e
∼0.7 eV, which was considered a transition point between the phases. The ratios of the atomic state population densities showed different features in the two phases, and are expected to be useful in characterizing the phase and degree of plasma detachment.
Multiple-wavelength Correlation and Variation Study for 3C 279 at Various Timescales
Authors: Chen Mingtai , Jiang Yunguo 
Published: September 2023

Abstract
The study on variation phenomena of blazars can shed light on the jet activity and structures. We collect nearly ten years γ-ray, X-ray, optical, and radio light curves of the target 3C 279, and use the local cross-correlation function to perform the correlation analysis among them. Based on lags among different wavelengths, we obtain that the optical as well as the X-ray emitting regions are

32.5

−
0.9

+
2.9

and

8.4

−
4.4

+
7.7

pc away from the jet base, and are upstream of the radio core region. The optical and γ-ray emitting regions are not completely co-spatial. We select several periods to study various variation phenomena at long-term, short-term, and very-short-term timescales. We find a redder when brighter trend of the optical color index at the quiescent state and a bluer when brighter trend at the active state. We also find a softer when brighter trend of the γ-ray at low luminosity and a possible harder when brighter trend at high luminosity. The correlation between the optical polarization and fluxes is complex. We find an anticorrelation for one long-term flare, and positive correlations for two short-term flares. The stack of the multiple optical components can explain the anticorrelation, while the appearance of a dominating component can explain the positive correlations. The disk plus many jet components scenario can explain the complex optical variation behaviors for 3C 279. As a remarkable intermediate synchrotron peaked blazar target, 3C 279 play an important role to understand the classification and transition between the low synchrotron peaked and high synchrotron peaked subclass of blazars, since its variation phenomena shows the indication of connection between these two categories.
Efficient Lossless Compression of Integer Astronomical Data
Authors: Maireles-González Òscar , Bartrina-Rapesta Joan , Hernández-Cabronero Miguel , Serra-Sagristà Joan 
Published: September 2023

Abstract
Each new generation of telescope produces increasingly larger astronomical data volumes, which are expected to reach the order of exabytes in the next decade. Effective and fast data compression methods are paramount to help the scientific community contain storage costs and improve transmission times. Astronomical data differs significantly from natural and Earth-observation images, asking for specifically tailored compression approaches. This paper presents a novel lossless compression technique that employs the discrete Haar wavelet transform within the JPEG 2000 standard. Its performance is compared to that of a comprehensive selection of compressors, including fpack, the most common technique in astronomical observatories, as well as other algorithms highly competitive for other types of data. Experiments are performed on a large data set of 16 bit integer images, produced by telescopes around the world and representative of a wide variety of astronomical scenarios. The proposed technique has two modes. The first mode outperforms all the other tested techniques in terms of compression performance. It surpasses the most competitive configuration of fpack by, respectively, 5.3% (about 0.3 bits per sample), having also 4.5% lower compression and decompression times. The second mode is the fastest among all tested techniques. Its compression and decompression times are 2.5 and 3.5 times faster than the fastest configuration of fpack, while also yielding a 2.4% better compression performance (0.15 bits per sample).
Simulating progressive motor neuron degeneration and collateral reinnervation in motor neuron diseases using a dynamic muscle model based on human single motor unit recordings
Authors: Sleutjes Boudewijn T H M , Stikvoort García Diederik J L , van Doorn Pieter A , Goedee H Stephan , van den Berg Leonard H 
Published: September 2023

Abstract

Objective. To simulate progressive motor neuron loss and collateral reinnervation in motor neuron diseases (MNDs) by developing a dynamic muscle model based on human single motor unit (MU) surface-electromyography (EMG) recordings. Approach. Single MU potentials recorded with high-density surface-EMG from thenar muscles formed the basic building blocks of the model. From the baseline MU pool innervating a muscle, progressive MU loss was simulated by removal of MUs, one-by-one. These removed MUs underwent collateral reinnervation with scenarios varying from 0% to 100%. These scenarios were based on a geometric variable, reflecting the overlap in MU territories using the spatiotemporal profiles of single MUs and a variable reflecting the efficacy of the reinnervation process. For validation, we tailored the model to generate compound muscle action potential (CMAP) scans, which is a promising surface-EMG method for monitoring MND patients. Selected scenarios for reinnervation that matched observed MU enlargements were used to validate the model by comparing markers (including the maximum CMAP and a motor unit number estimate (MUNE)) derived from simulated and recorded CMAP scans in a cohort of 49 MND patients and 22 age-matched healthy controls. Main results. The maximum CMAP at baseline was 8.3 mV (5th–95th percentile: 4.6 mV–11.8 mV). Phase cancellation caused an amplitude drop of 38.9% (5th–95th percentile, 33.0%–45.7%). To match observations, the geometric variable had to be set at 40% and the efficacy variable at 60%–70%. The Δ maximum CMAP between recorded and simulated CMAP scans as a function of fitted MUNE was −0.4 mV (5th–95th percentile = −4.0 – +2.4 mV). Significance. The dynamic muscle model could be used as a platform to train personnel in applying surface-EMG methods prior to their use in clinical care and trials. Moreover, the model may pave the way to compare biomarkers more efficiently, without directly posing unnecessary burden on patients.
X-ray spectroscopy with a photon-counting SiPM-based scintillation detector
Authors: Ceravolo S. , Gargiulo R. , Paesani D. , Russo A. , Sarra I. 
Published: September 2023

Abstract
A new low-energy X-ray detector was built and operated, using a plastic scintillator coupled to a large area SiPM.
The signal is amplified with a low-noise, high gain, custom circuit providing excellent photon-counting capabilities and allowing a quasi-digital measurement.
The detector was tested using X-rays coming from molybdenum K lines (17.4 and 19.6 keV), and an energy resolution of 28% is obtained with 20 photoelectrons per X-ray photon on average.
Finite element analysis of ball burnishing: evolution of residual stresses and surface profile in Ti-6Al-7Nb alloy
Authors: Chaudhary Abhishek , Baral Subrat Kumar , Tiwari Gaurav , Dumpala Ravikumar 
Published: September 2023

Abstract
In the present study, the effect of feed on the residual stress distribution and surface profile generated during the ball burnishing of titanium alloy (Ti-6Al-7Nb) was investigated using finite element simulation. The elastic-plastic material model with isotropic hardening was used for performing the simulations. The created finite element model containing a rigid ball and deformable specimen was optimized and validated using experimental data. It was observed that the effect of burnishing feed is significant on the surface profile compared to residual stresses. The maximum residual stress obtained during the simulation of the process was achieved for the burnishing feed of 0.2 mm. This confirmed the variation of residual stress when the burnishing feed is varied. Whereas the surface roughness was the least for the 0.05 mm burnishing feed which was due to uniform deformation of the surface during the process.
The effect of Dunaliella tertiolecta supplementation on diet-induced obesity in UCP1-deficient mice
Authors: Yamashita Yukari , Takeuchi Tamaki , Endo Yuki , Goto Ayumi , Uno Misa , Sakaki Setsuko , Yamaguchi Yuji , Takenaka Hiroyuki , Yamashita Hitoshi 
Published: September 2023

ABSTRACT
We previously demonstrated that dietary supplementation with Dunaliella tertiolecta (DT) increases uncoupling protein 1 (UCP1) expression in brown adipose tissue (BAT) and improves diet-induced obesity (DIO) in C57BL/6 J mice at thermoneutrality (30 °C). Here, we investigated whether DT improves DIO in a thermoneutral UCP1-deficient (KO) animal. KO mice were fed a high-fat diet supplemented with DT for 12 weeks. Compared to control group without DT, body weight was significantly reduced in DT group with no difference in food intake. Dunaliella tertiolecta-supplemented mice exhibited lower adiposity and well-maintained multilocular morphology in BAT, in which a significant increase in gene expression of PR domain containing 16 was detected in DT group compared to control group. Moreover, increase in UCP2 level and/or decrease in ribosomal protein S6 phosphorylation were detected in adipose tissues of DT group relative to control group. These results suggest that DT supplementation improves DIO by stimulating UCP1-independent energy dissipation at thermoneutrality.
Bacterial community structure and assembly dynamics hinge on plant litter quality
Authors: Min Kaikai , Zheng Tiantian , Zhu Xuefeng , Bao Xuelian , Lynch Laurel , Liang Chao 
Published: September 2023

Abstract
Litter decomposition is a fundamental ecosystem process controlling the biogeochemical cycling of energy and nutrients. Using a 360-day lab incubation experiment to control for environmental factors, we tested how litter quality (low C/N deciduous vs. high C/N coniferous litter) governed the assembly and taxonomic composition of bacterial communities and rates of litter decomposition. Overall, litter mass loss was significantly faster in soils amended with deciduous (DL) rather than coniferous (CL) litter. Communities degrading DL were also more taxonomically diverse and exhibited stochastic assembly throughout the experiment. By contrast, alpha-diversity rapidly declined in communities exposed to CL. Strong environmental selection and competitive biological interactions induced by molecularly complex, nutrient poor CL were reflected in a transition from stochastic to deterministic assembly after 180 days. Constraining how the diversity and assembly of microbial populations modulates core ecosystem processes, such as litter decomposition, will become increasingly important under novel climate conditions, and as policymakers and land managers emphasize soil carbon sequestration as a key natural climate solution.
Stagnant-lid convection: comparison of viscosity laws and uniform scaling approach for temperature and heat flux prediction
Authors: Grigné Cécile 
Published: September 2023

SUMMARY
Numerical simulations of stagnant-lid convection in a 2-D Cartesian fluid heated from below are carried out in order to study how the temperature dependence of the viscosity affects the vertical profile of temperature in the model. I test different viscosity laws, including the Arrhenius law with realistic parameters for the Earth’s mantle or for icy bodies. No approximation is made, which leads to extremely high viscosity contrasts. Results are compared to different approximations, in particular the Frank–Kamenetskii (FK) one. I propose a new approach for the scaling of the temperature drop across the convective part of the layer beneath the stagnant lid. The vertical profile of temperature as a function of the viscosity law is predicted, with a uniform scaling approach for all formulations of the temperature-dependent viscosity. The predicted profiles are in very good agreement with results of 2-D numerical simulations in Cartesian geometry. The complete scaling given here provides a rapid way to compare viscosity laws and to check how approximations affect the results, in terms of interior temperature, stagnant lid thickness and heat flux, compared to the real Arrhenius law for rocky mantles and for the icy outer shells of satellites. In particular, in the context of 2-D Cartesian convection heated from below, in the stagnant-lid regime, I propose a new approach to properly scale the FK formulation when it is used as an approximation of the Arrhenius law.