bluuebunny/crossref_metadata_2025 huggingface dataset:
A Review of the Effect of Classroom Sound-Field Amplification on Children in Primary School
Authors: Mealings Kiri
Published: March 2022

Purpose:

Being able to hear the teacher clearly is an important factor for children's learning. However, classrooms often have suboptimal listening conditions. Sound-field amplification systems (SFAS) can help improve classroom listening conditions by increasing the level of the teacher's speech compared to the background noise throughout the classroom. The aim of this review article was to review the effect of SFAS on children in primary school.

Method:

A comprehensive search of four online databases (ERIC, PubMed, Scopus, and Web of Science) was conducted. The search terms were
classroom sound-field amplification
and
classroom amplified distribution system.
Twenty-one articles were deemed relevant for the review plus an additional six from their references.

Results:

Most articles were published between 1996 and 2015. Only one article was published since 2016. A range of child populations were studied including typically developing children and children with difficulties and disabilities such as hearing loss, developmental language disorders, attention-deficit/hyperactivity disorder, emotional and behavior disorders, Down syndrome, and developmental disabilities. There were several different measures that were used to evaluate the effectiveness of SFAS including speech perception assessments, language assessments, academic and comprehension assessments, classroom observations, interviews, and questionnaires. Improvements with SFAS were found for speech perception, listening comprehension and auditory analysis, language outcomes, academic outcomes, and behavior.

Conclusion:

SFAS can benefit children's listening and learning; however, the child's background, classroom reverberation time (limit to < 1 s), and layout and type of learning activities, especially in modern classrooms, need to be taken into consideration.
Psychomotricité ou la résistance au clivage corps psyché
Authors: Potel Catherine
Published: March 2022

Dans son introduction, Catherine Potel repart des origines de la psychomotricité qui, dès l’énoncé de son titre, met au centre de son objet d’étude toute la question de la complexité de l’humain. Elle insiste sur la première des mises en sens de ce « métier à tisser » - quasi artisanal » par la simplicité des médiations psychocorporelles proposées aux patients - celle d’une résistance au clivage corps psyché qui menace tous ceux qui souffrent, dans leur corps ou dans leur psyché. La globalité de l’être est l’ancrage même de la psychomotricité.
Anorexie mentale et psychomotricité : parcours atypique d’une jeune femme de 18 ans
Authors: Védérine Florian
Published: March 2022

Aditi, 18 ans, est hospitalisée à temps complet en service de psychiatrie pour troubles des conduites alimentaires. Notre rencontre se fait dans le cadre d’une thérapie psychomotrice. Ce soin, corrélé aux suivis psychologiques, psychiatriques, infirmiers et diététiques a permis à cette jeune femme d’extérioriser ses émotions et d’accepter un avenir qui l’effrayait. Cet article retrace certaines étapes de régression utiles à Aditi pour s’autoriser des comportements qu’elle considérait comme honteux et ainsi accepter sa majorité et son rôle de femme de façon singulière, loin des injonctions sociétales paralysantes. L’alliance thérapeutique co-créée s’inscrit dans la psychiatrie transférentielle où le soin ne s’entend pas seulement comme l’application d’une technique mais où il s’élabore autour d’une adaptation conjointe et une compréhension des besoins non verbalisés.
Schwindel und Tinnitus
Authors: Bonacker Michael
Published: March 2022

In diesem Artikel werden die Untersuchung und Behandlung von Schwindel und/oder Tinnitus nach fachärztlicher Abklärung erläutert. Dabei wird auf die ausführliche Anamnese, neurologische
Tests, ganzkörperliche osteopathische Untersuchung und ursachenbezogene Behandlungsmethoden eingegangen. Kraniale und zervikoenzephale Funktionsstörungen können nach entsprechender
Behandlung zu einer Symptomverbesserung führen. Sollte nach osteopathischer Intervention keine Besserung eintreten, müssen weitere fachärztliche Untersuchungen erfolgen.
Brønsted Acidic Ionic Liquid Catalyzed Three-Component Friedel–Crafts Reaction for the Synthesis of Unsymmetrical Triarylmethanes
Authors: Sirion Uthaiwan , Rinkam Suttida , Senapak Warapong , Watchasit Sarayut , Saeeng Rungnapha
Published: March 2022

A convenient and practical method for the synthesis of unsymmetrical triarylmethanes was demonstrated through a one-pot three-component double Friedel–Crafts reaction of various aliphatic, aromatic, or heteroaromatic aldehydes with N,N-dialkylanilines and indoles by using a Brønsted acidic ionic liquid as the catalyst. This method was successfully applied under metal- and solvent-free conditions at 80 °C, affording the corresponding unsymmetrical triarylmethane products in moderate to high yields from a broad range of substrates. In addition, the mechanism of this reaction was studied by quantitative NMR analysis.
Study of a position-sensitive scintillator neutron detector prototype based on 6LiF/ZnS scintillator and silicon photomultiplier arrays readout
Authors: Tang Mengjiao , Yu Qian , Huang Chang , Tang Bin , Sun Zhijia , Zhao Weijuan , Wei Guangyou , Cai Xiaojie , Yue Xiuping , Zhou Shihui
Published: March 2022

Due to the shortage of the 3He gas and its rapidly increasing price, scintillator detectors, the advantages of which are high spatial resolution and capability of detection in real time, become widely used in many neutron instruments. In this work, a position-sensitive neutron detector consisting of a 6LiF/ZnS scintillation screen and a silicon photomultiplier array linked to a capacitive network to detect the positions of incident neutrons, is constructed and tested. To evaluate the detector performance, a series of neutron beam experiments with the detector prototype were performed in the BL20 at the China Spallation Neutron Source. The spatial resolution was measured, and the energy-selective neutron imaging and Bragg edge measurements of a 316L stainless steel sample were performed. A sub-millimeter spatial resolution could be obtained for the detector prototype under study. The detector with such a high spatial resolution is promising for applications in neutron scattering experimental installations, especially for neutron single-crystal diffractometers.
Design and experimental research of a 28 GHz TE01 mode 160° miter bend for electron cyclotron resonance ion source
Authors: Liu Jianwei , Guo Junwei , Wang Lina , Niu Xinjian , Qi Lanyue , Sun Xu
Published: March 2022

In this paper, a 28 GHz TE01 mode 160° miter bend employing two plane mirrors is proposed based on the quasi-optical technique and the coupled wave theory to realize high-efficiency transmission for the electron cyclotron resonance ion source. First, the TE01 mode was converted to TE0n hybrid modes with Gaussian beam characteristics by means of the designed mode converter. Second, the phase shift section was implemented to eliminate the phase difference of the hybrid modes. Then, upon reflection of two plane mirrors, the propagation direction of a wave beam is deviated by 160°. Finally, the hybrid modes were converted to the TE01 mode using the same structures of the phase shift section and the mode converter. The simulation results reveal that the TE01 mode transmission efficiency reaches 95.22% at the central frequency of 28 GHz. Additionally, the designed 160° miter bend has been fabricated, installed, and measured. The experimental results show that the power transmission efficiency reaches 98.54% including diffraction losses and ohmic losses.
Rayleigh wave and super-shear evanescent wave excited by laser-induced shock at a soft solid–liquid interface observed by photoelasticity imaging technique
Authors: Nguyen Thao Thi Phuong , Tanabe-Yamagishi Rie , Ito Yoshiro
Published: March 2022

We investigated laser-induced shock excitation of elastic surface waves at a free surface and a soft solid–liquid interface using a custom-designed photoelasticity imaging technique. Epoxy-resin and pure water were selected as the solid and liquid media. The elastic surface waves were excited via a shock process induced by focusing a single nanosecond laser pulse on the solid surface. To confirm the experimental observations, the roots of the Rayleigh and Stoneley equations were calculated. For a free surface, we present an entire-field observation of elastic surface waves, which includes a super-shear evanescent wave (SEW) that propagates faster than the shear wave but slower than the longitudinal wave. For a soft solid–liquid interface, we demonstrate the presence of a non-leaky Rayleigh wave that corresponds to a real root of the Stoneley equation. We also evidence the existence of a SEW that propagates 1.7 times faster than the shear speed in the solid and corresponds to a complex conjugate root of the Stoneley equation. These results correct the previously accepted notion that the Scholte wave is the only surface wave that can be generated at a soft solid–liquid interface.
Disordering effect of the ammonium cation accounts for anomalous enhancement of heterogeneous ice nucleation
Authors: Whale Thomas F.
Published: March 2022

Heterogeneous nucleation of ice from supercooled water is the process responsible for triggering nearly all ice formation in the natural environment. Understanding of heterogeneous ice nucleation is particularly key for understanding the formation of ice in clouds, which impacts weather and climate. While many effective ice nucleators are known, the mechanisms of their actions remain poorly understood. Some inorganic nucleators have been found to nucleate ice at warmer temperatures in dilute ammonium solution than in pure water. This is surprising, analogous to salty water melting at a warmer temperature than pure water. Here, the magnitude of this effect is rationalized as being due to thermodynamically favorable ammonium-induced disordering of the hydrogen bond network of ice critical clusters formed on inorganic ice nucleators. Theoretical calculations are shown to be consistent with new experimental measurements aimed at finding the maximum magnitude of the effect. The implication of this study is that the ice-nucleating sites and surfaces of many inorganic ice nucleators are either polar or charged and, therefore, tend to induce formation of hydrogen-ordered ice clusters. This work corroborates various literature reports, indicating that some inorganic ice nucleators are most effective when nominally neutral, and implies a commonality in mechanism between a wide range of inorganic ice nucleators.
Understanding the coexistence of unipolar and bipolar resistive switching in NiFe2O4 resistive memory devices
Authors: Li Jiacheng , Yao Chuangye , Ke Yifu , Huang Wenhua , Thatikonda Santhosh Kumar , Qin Ni , Bao Dinghua
Published: March 2022

In this Letter, spinel ferrite NiFe2O4 films prepared through pulsed laser deposition are used to fabricate Pt/NiFe2O4/Pt devices with the coexistence of unipolar resistive switching (URS) and bipolar resistive switching (BRS). The device demonstrated nonvolatile and stable resistive switching (RS) properties under URS and BRS modes. The current–voltage (I–V) fitting analysis and temperature dependence measurements suggested that one Pt/NiFe2O4/Pt RRAM cell follows two significantly different RS and carrier transport mechanisms under URS and BRS modes. Under URS mode, the carrier mechanism alternates between the high resistance state (HRS) with Schottky emission and low resistance state (LRS) with the Ohmic mechanism. In contrast, under BRS mode, carrier transport at HRS and LRS is dominated by space-charge-limited current and nearest-neighboring hopping, respectively. Finally, a physical model, combining oxygen ion (O2−) migration and electric field distribution simulated by COMSOL Multiphysics, is proposed to further clarify the coexistence of two distinct RS and carrier transport mechanisms in the single Pt/NiFe2O4/Pt RRAM device.
Hybrid quantum-classical simulations of magic angle spinning dynamic nuclear polarization in very large spin systems
Authors: Perras Frédéric A. , Carnahan Scott L. , Lo Wei-Shang , Ward Charles J. , Yu Jiaqi , Huang Wenyu , Rossini Aaron J.
Published: March 2022

Solid-state nuclear magnetic resonance can be enhanced using unpaired electron spins with a method known as dynamic nuclear polarization (DNP). Fundamentally, DNP involves ensembles of thousands of spins, a scale that is difficult to match computationally. This scale prevents us from gaining a complete understanding of the spin dynamics and applying simulations to design sample formulations. We recently developed an ab initio model capable of calculating DNP enhancements in systems of up to ∼1000 nuclei; however, this scale is insufficient to accurately simulate the dependence of DNP enhancements on radical concentration or magic angle spinning (MAS) frequency. We build on this work by using ab initio simulations to train a hybrid model that makes use of a rate matrix to treat nuclear spin diffusion. We show that this model can reproduce the MAS rate and concentration dependence of DNP enhancements and build-up time constants. We then apply it to predict the DNP enhancements in core–shell metal-organic-framework nanoparticles and reveal new insights into the composition of the particles’ shells.
High-throughput single nucleotide polymorphism genotyping reveals population structure and genetic diversity of tall fescue (
Authors: Shahabzadeh Zeynab , Darvishzadeh Reza , Mohammadi Reza , Jafari Morad , Alipour Hadi
Published: March 2022

Single nucleotide polymorphisms (SNPs) are the most abundant form of genetic variation in eukaryote genomes and may be useful for selection of genetically distant parents for crossing in breeding programs. In this study, genome-wide SNPs of tall fescue (Festuca arundinacea Schreb.) were genotyped by using double-digest restriction-site-associated DNA sequencing to determine the genetic variation and differentiation among and within forage, turf and hybrid populations. After filtering, 16 036 SNPs were used to investigate genetic diversity and for structure analysis. SNP markers clearly differentiated the populations from each other. However, the hybrid population had a higher genetic similarity with the turf population than with the forage population. The results were confirmed by genetic differentiation (fixation index, Fst) and gene flow (Nm) statistics, so that low Fst and high Nm were observed between turf and hybrid groups, indicating less genetic distance and a high similarity between them. Based on the results of the weighted pair group method with arithmetic mean clustering, discriminant analysis of principal components and analysis of molecular variance, greater genetic differentiations were found among diverse turf, forage and hybrid populations, especially between turf and forage ones. In conclusion, numerous informative SNPs, natural allelic diversity-led domestication patterns, basic genetic variation statistics (e.g. Fst and heterozygosity) and population structures have multidimensional applicability for tall fescue genomics-assisted breeding.
Thermal imaging outshines spotlighting for detecting cryptic, nocturnal mammals in tropical rainforests
Authors: Underwood Avril H. , Derhè Mia A. , Jacups Susan
Published: March 2022

Context Thermal imaging has been shown to be a valuable technique for detecting a range of terrestrial mammals across different environments. The limited studies looking at its effectiveness in detecting arboreal mammals in rainforest ecosystems have had mixed success due to the complexity of the environment and limitations of the technology itself. Aims We investigated whether using a hand-held thermal imaging device would detect more individuals of six species of nocturnal arboreal mammal in tropical rainforests than the most-used detection method of spotlighting. We determined whether environmental variables effecting either equipment operation or mammal behaviour would influence these results. Methods We surveyed eight transects across the Wet Tropics of northern Queensland for six species of arboreal mammals using both a hand-held thermal imager and a spotlight. We used a measure of underestimation to compare counts of individual species, and then modelled total mammal counts with detection method and environmental variables to find the best approximating model. Key results Spotlighting underestimated the total number of each species by between 33 and 100% when compared with thermal imaging. Detection method alone without any environmental interaction term provided the best approximating model (AICc = 275.58, marginal pseudo R2 = 0.286), with thermal imaging technology detecting almost double the number of our target individuals (12.3 ± 1.76) compared with spotlighting (6.7 ± 1.02). Conclusions Despite recorded operational limitations, thermal imaging technology greatly improved our ability to locate both small and large nocturnal, arboreal mammals, including a species that is rarely observed in the wild. Implications The potential to not only improve detection of nocturnal, arboreal mammals but also improve cryptic species distribution and abundance measures suggests thermal imaging technology is an important tool for use globally across rainforests environments.
Dynamic gene expression and growth underlie cell-to-cell heterogeneity in
Escherichia coli
stress response
Authors: Sampaio Nadia M. V. , Blassick Caroline M. , Andreani Virgile , Lugagne Jean-Baptiste , Dunlop Mary J.
Published: March 2022

Significance

Individual bacteria that share identical genomes and growth environments can display substantial cell-to-cell differences in expression of stress-response genes and single-cell growth rates. This phenotypic heterogeneity can impact the survival of single cells facing sudden stress. However, the windows of time that cells spend in vulnerable or tolerant states are often unknown. We quantify the temporal expression of a suite of stress-response reporters, while simultaneously monitoring growth. We observe pulsatile expression across genes with a range of stress-response functions, finding that single-cell growth rates are often anticorrelated with reporter levels. These dynamic phenotypic differences have a concrete link to function, in which individual cells undergoing a pulse of elevated expression and slow growth are predisposed to survive antibiotic exposure.
Cytokinin–CLAVATA cross-talk is an ancient mechanism regulating shoot meristem homeostasis in land plants
Authors: Cammarata Joseph , Morales Farfan Christopher , Scanlon Michael J. , Roeder Adrienne H. K.
Published: March 2022

Significance

Plants grow from their tips. The gametophore (shoot-like organ) tip of the moss
Physcomitrium patens
is a single cell that performs the same functions as those of multicellular flowering plants, producing the cells that make leaves and regenerating new stem cells to maintain the shoot tip. Several pathways, including CLAVATA and cytokinin hormonal signaling, regulate stem cell abundance in flowering plants and in mosses, although the mechanisms whereby these pathways regulate stem cell abundance and their conservation between these plant lineages is poorly understood. Using moss, we investigated how
Pp
CLAVATA and cytokinin signaling interact. Overall, we found evidence that
Pp
CLAVATA and cytokinin signaling interact similarly in moss and flowering plants, despite their distinct anatomies, life cycles, and evolutionary distance.
Exploring global changes in agricultural ammonia emissions and their contribution to nitrogen deposition since 1980
Authors: Liu Lei , Xu Wen , Lu Xiankai , Zhong Buqing , Guo Yixin , Lu Xiao , Zhao Yuanhong , He Wei , Wang Songhan , Zhang Xiuying , Liu Xuejun , Vitousek Peter
Published: March 2022

Significance

Agricultural systems are already major forces of ammonia pollution and environmental degradation. How agricultural ammonia emissions affect the spatio-temporal patterns of nitrogen deposition and where to target future mitigation efforts, remains poorly understood. We develop a substantially complete and coherent agricultural ammonia emissions dataset in nearly recent four decades, and evaluate the relative role of reduced nitrogen in total nitrogen deposition in a spatially explicit way. Global reduced nitrogen deposition has grown rapidly, and will occupy a greater dominant position in total nitrogen deposition without future ammonia regulations. Recognition of agricultural ammonia emissions on nitrogen deposition is critical to formulate effective policies to address ammonia related environmental challenges and protect ecosystems from excessive nitrogen inputs.
Pedagogical devices
Authors: Sterk Darryl
Published: March 2022

The “partial translation” of Inuktitut-language lyrics in the Indigenous filmAtanarjuat: The Fast Runner(directed by Zacharias Kunuk, 2001) has been interpreted as a means of challenging outsiders to understand the film “emically,” meaning from insiders’ perspectives. On this interpretation,Atanarjuatis linguistically exclusionary, because the challenge of partial translation effectively excludes most outsiders from a full understanding. But given the problem of language shift in Indigenous communities, we should not expect Indigenous films to be linguistically exclusionary in general, or they would exclude young Indigenous insiders along with outsiders. We should instead expect Indigenous films to adopt an inclusionary approach to subtitling, consistent with projects of language revitalization. To see what form such an approach might take, I analyzed three Indigenous films from Taiwan in which speech in Atayalic languages is subtitled in Mandarin. Staggered over three-and-a-half decades, these three films index the subtitling approach as a function of concern about language shift. I found that all three films were fully, not partially translated, but that the two films made in a context of concern about language shift were subtitled pedagogically. The two pedagogically subtitled films are “devices” for the pedagogy of Atayal, the most widely spoken Atayalic language. This result from Taiwan suggests that a pedagogical approach might be common in the subtitling of Indigenous films in settler societies around the world.
Theoretical investigation on un-doped and doped TiO2 for solar cell application
Authors: Dharmale Neerja , Chaudhury Saurabh , Kumar Pandey Chandan
Published: March 2022

Enhancing solar cell efficiency is one of the most challenging and demanding topics for PV researchers. An ab initio study is done here on the structure of crystal, formation energies, electronic structure, the density of states, effective mass, and optical properties of pure and S-doped, Fe-doped, and Fe-/S-doped anatase TiO2. Co-doping causes a significant reduction in the bandgap, suppresses the charge carrier’s recombination rate, and shifted absorption spectra from UV to the visible region. Hence, co-doped anatase TiO2 with Fe and S is more favorable as a buffer layer of the solar cell compared to S-doped and Fe-doped TiO2. The forecasted values of all quantities will benefit researchers to examine these materials for further photovoltaic applications.
Synthesis of silver/K-Caragenan nanocomposites assisted with microwave iradiation as a potential antibacterial material
Authors: Pramesti E S , Febriani N A , ‘Aisy R N , Salsabila S , Rachmawati V P N , Susilowati E
Published: March 2022

In this research, a silver/K-carrageenan nanocomposite was synthesized using a chemical reduction method assisted by microwave irradiation using NaOH as an accelerator. The aims of this research is to determine the optimum conditions for the preparation of silver nanoparticles with NaOH variations, microwave irradiation time and, AgNO3 concentration. AgNO3 compounds function as precursors and K-carrageenan as a reducing agent, stabilizer and also a matrix in silver-K-Carrageenan nanocomposites. The formation of silver nanoparticles was identified using a UV-Vis spectrophotometer which is associated with the LSPR phenomenon. Testing of antibacterial activity using the diffusion method against S.Aureus bacteria. The results showed that the silver nanoparticles formed on the silver/K-Carrageenan nanocomposite were characterized by the appearance of an absorption band in the 400 nm region. NaOH concentration, irradiation time and AgNO3 concentration affect the absorbance value at the maximum absorption, which indicates the effect on the amount of silver nanoparticles. The optimal condition for the synthesis of silver nanoparticles is the use of NaOH 0,014 M with an irradiation time of 6 minutes. The concentration of AgNO3 precursor is directly proportional to the amount of silver nanoparticles formed in the nanocomposite. Silver/K-Carrageenan nanocomposite has high antibacterial activity and potential as antibacterial material.
Preparation and characterization of microcrystalline cellulose from lembang (Typha angustifolia L. )
Authors: Adawiyah R , Suryanti V , Pranoto
Published: March 2022

The study of preparation and characterization of microcrystalline cellulose from the Lembang / narrowleaf cattail(Typha angustifoliaL.) has been carried out. Alkalinization was done to remove lignin and hemicellulose compounds. The bleaching process was done by adding 4 M HCl at 65 oC for 3 hours and then sonicated for 10 minutes. The cellulose yield obtained was 32.2%. The Fourier Transform Infrared (FTIR) spectra indicated the appearance of some specific functional groups (O-H, -C-H, =C-H and C-O, and C-O-C). Scanning Electron Microscope (SEM) showed that the structure of cellulose is a long crystalline with a diameter of 3.1 µm. Thermogravimetric analysis (TGA) showed decomposition at higher temperatures of 349.13, 366.66 and 353.24 oC for cellulose after hydrolysis, cellulose before hydrolysis, and TaL powder. Crystalline index and crystalline size of microcrystalline cellulose analyzed by X-Ray Diffraction (XRD) were 71.1% and 2.4 nm, respectively.
Development and validation of analytical methods for multicomponent crystals of ibuprofen with malic and tartaric acid using spectrophotometry
Authors: Susilo S P , Pertiwi S H , Ainurofiq A
Published: March 2022

Various chemical substances have been used as pharmaceutical active ingredients, such as ibuprofen, which is an analgesic. The validity of an analytical method of a pharmaceutical active ingredient combined with co-formers into one single phase should be confirmed so that the analysis can be well received. Therefore, this study aims to validate the analytical method of ibuprofen in multicomponent crystals using a UV spectrophotometer with the parameters of linearity, accuracy, precision, and placebo interference. Ibuprofen was dissolved in phosphate buffer with a pH of 7.2 using ethanol as co-solvent. The solution was diluted and analyzed to obtain the maximum wavelength. The calibration curve was analyzed to obtain the linear regression equation for ibuprofen to determine linearity. The accuracy and precision parameters were measured by the results of replications. Meanwhile, placebo interference was determined using an equimolar ratio of 1:1 between ibuprofen with malic acid and tartaric acid. The results of the analysis showed that ibuprofen had a maximum wavelength of 265 nm. The linearity, accuracy, precision, and placebo interference fulfilled the requirement. Based on the validation parameter performed, the analytical method used was valid for the analysis of ibuprofen multicomponent crystals with malic acid and tartaric acid as co-formers.
Synthesized and release study of labelled small mesoporous silica nanoparticle as theranostic material
Authors: Safitriono W N , Lestari W A , Wahyuningsih S , Suryanti V , Gomez-Ruiz S , Wibowo F R
Published: March 2022

Combination of diagnosis and therapy, which is called theranostic, became great concern to treat cancer. Mesoporous silica nanoparticle (MSN) has several features, such as high surface area, biocompatible, and non-toxic, which support as potential theranostic materials. In this study, we have successfully synthesized small MSN and modification by addition of imaging agent. The small particle size and porosity were beneficial for its high colloidal stability and high surface area to accommodate drugs. Labelled small MSN (LMSN) can emit the energy which will be useful for diagnosis matter. In addition, we functionalized LMSN by polyelectrolyte addition to increase its sensitivity. The drug released showed that functionalization on the surface produced more sensitive drug release profile which is triggered by pH.
Corrections to scaling in geometrical clusters of the 2D Ising model
Authors: Akritidis Michail , Fytas Nikolaos G , Weigel Martin
Published: March 2022

We study the scaling of the average cluster size and percolation strength of geometrical clusters for the two-dimensional Ising model. By means of Monte Carlo simulations and a finite-size scaling analysis we discuss the appearance of corrections to scaling for different definitions of cluster sets. We find that including all percolating clusters, or excluding only clusters that percolate in one but not the other direction, leads to smaller corrections to scaling for the average cluster size as compared to the other definitions considered. The percolation strength is less sensitive to the definitions used.
Study of diluted kinetic Ising model under sinusoidal external field
Authors: Chattopadhyay Sourav , Santra S. B.
Published: March 2022

The ferromagnet to paramagnet phase transition temperature depends on the dilution concentration in the site diluted Ising ferromagnet. Though this model is a bistable system, few studies reported dynamic phase transition (DPT) in diluted Ising ferromagnet. We study dilution-dependent DPT in diluted Ising ferromagnet via Monte Carlo simulation under a time-varying external field tuning the system’s temperature on several system sizes. The nature of the transition is characterized by employing the finite-size scaling study.
Quantifying uncertainty with stochastic collocation in the kinematic magentohydrodynamic framework
Authors: Rajbhandari E. , Gibson N.L. , Woodside C. R.
Published: March 2022

We discuss an efficient numerical method for the uncertain kinematic magnetohydrodynamic system. We include aleatoric uncertainty in the parameters, and then describe a stochastic collocation method to handle this randomness. Numerical demonstrations of this method are discussed. We find that the shape of the parameter distributions affect not only the mean and variance, but also the shape of the solution distributions.
Diffusional characteristics of a Newtonian event-chain Monte Carlo in hard disk systems
Authors: Banno H , Mugita D , Isobe M
Published: March 2022

The equilibration and relaxation times of the physical properties of time correlation functions have historically been of fundamental importance in terms of molecular simulation. An efficient algorithm for the acceleration of equilibration, termed the ‘event-chain Monte Carlo’ has been investigated over the past decade. Recently, by adding the collision rule often used in event-driven molecular dynamics, a Newtonian event-chain Monte Carlo was developed. In this event-chain Monte Carlo and variants thereof, optimal performance strongly depends on chain length, physical properties, and system size; the microscopic mechanism in play remains elusive. To identify key factors affecting equilibration, we investigated the diffusional characteristics per event (collision) for each algorithm, focusing systematically on the diffusion coefficients and pair dispersions in two-dimensional hard disk systems.
Theoretical Study of Complex Aspirin and Hydroxypropyl-β-cyclodextrin in Solvent Phase
Authors: Jayyinunnisya H , Solihat L S , Sugimori K , Kawaguchi K , Nagao H
Published: March 2022

We estimate the configuration of complex ASA/HPCD in the gas phase by using PM3 and B3LYP methods. Some physical properties in the gas phase, such as complexation energy, deformation energy, dipole moment, etc., are calculated by using PM3 and B3LYP methods. We investigate the dependence of physical properties such as complexation energy, etc., on solvation by using PM3 and B3LYP methods with the PCM method. Complex ASA/HPCD becomes more stable than the dissociation state. The present results suggest that the effect of solvent can be increasing the energy complexation, LUMO energy, HOMO energy, HOMO-LUMO gap energy, electronic potential, and chemical hardness, whereas the electrophilicity decrease.
Simulation study of the function of domain swapping in the HSP90 chaperone cycle
Authors: Matsukura L , Miyashita N
Published: March 2022

HSP90 is one of the molecular chaperones, and it is known as an anti-cancer drug target. In the HSP90 chaperone cycle, when the ATP binds to the HSP90NTD, the HSP90 dimer forms a domain swapping in NTD. The stability of the HSP90 dimer is essential to the HSP90 chaperon cycle process. We have performed several molecular dynamics simulations of the HSP90 dimer to investigate how ATP binding and domain swapping have affected the stability. We analysed the fluctuation of critical residues for ATP binding and ATP hydrolysis in the HSP90NTD dimer conformation. As a result, we found that domain swapping is essential to the stability of the HSP90 dimer, while ATP is not so essential for the stability of the dimer conformation.
Quantum Game Theory approach for data network routing: a solution for the congestion problem
Authors: Agustin Silva , Omar G. Zabaleta , Constancio M. Arizmendi
Published: March 2022

Because of the sustained growth of information and mobile users transmitting a great amount of data packets, modern network performances are being seriously affected by congestion problems. In fact, congestion management is a challenging task that can be roughly summarized as a trade off between transmission latency and cost. In this context, a novel framework is proposed for solving the congestion problem on communication networks using a quantum game theory model, where network packets compete selfishly for the shortest route. Simulations show that final network routing and traveling times achieved with the quantum game version outperform those obtained classically. This leads to the opportunity of developing full-stack protocols that may be capable of taking advantage of the quantum properties for optimizing communication systems. Due to its generality, the game theoretic approach can be applied both in local networks and in more complex networks such as 5G or LTE-A.
Predicting the Expansion of Supernova Shells for High-Resolution Galaxy Simulations Using Deep Learning
Authors: Hirashima K. , Moriwaki K. , Fujii M. S. , Hirai Y. , Saitoh T. , Makino J.
Published: March 2022

Small integration timesteps for a small fraction of the particles become a bottleneck for future galaxy simulations with a higher resolution, especially for massively parallel computing. As we increase the resolution, we must resolve physics on a smaller timescale while the total integration time is fixed as the universe age. The small timesteps for a small fraction of the particles worsen the scalability. More specifically, the regions affected by supernovae (SN) have the smallest timestep in the whole galaxy. Using a Hamiltonian splitting method, we calculate the SN regions with small timesteps using a few thousand CPU cores but integrate the entire galaxy using a shared timestep. For this approach, we need to pick up particles in regions, which will be affected by SN (the target particles) by the next global step (the integration timestep for the entire galaxy) in advance. In this work, we developed the deep learning model to predict the region where the shell due to a supernova explosion expands during one global step. In addition, we identify the target particles using image processing of the density distribution predicted by our deep learning model. Our algorithm could identify the target particles better than the method based on the analytical solution. This particle selection method using deep learning and the Hamiltonian splitting method will improve the performance of galaxy simulations with extremely high resolution.
ISTEDDAS: a new direct N-Body code to study merging compact-object binaries
Authors: Mencagli Mattia , Nazarova Natalia , Spera Mario
Published: March 2022

On September 14, 2015, the two detectors of the Laser Interferometer Gravitational wave Observatory (LIGO) reported the first detection of gravitational waves, a signal generated from the coalescence of two stellar-mass black holes. The discovery represented the beginning of an entirely new way to investigate the Universe. From the theoretical point of view, the formation and evolution of compact-object binaries are still very uncertain. One of the main issues is that most stars form in dense stellar environments, and numerical simulations of merging compact-object binaries in such crowded stellar systems are very challenging. In this work, we review the main numerical bottlenecks that hamper our knowledge on merging binaries in dense environments and we present a new GPU-accelerated N-body code, which is currently under development, called isteddas, that can overcome most of the obstacles.
General purpose lattice QCD code set Bridge++ 2.0 for high performance computing
Authors: Akahoshi Yutaro , Aoki Sinya , Aoyama Tatsumi , Kanamori Issaku , Kanaya Kazuyuki , Matsufuru Hideo , Namekawa Yusuke , Nemura Hidekatsu , Taniguchi Yusuke
Published: March 2022

Bridge++ is a general-purpose code set for a numerical simulation of lattice QCD aiming at a readable, extensible, and portable code while keeping practically high performance. The previous version of Bridge++ is implemented in double precision with a fixed data layout. To exploit the high arithmetic capability of new processor architecture, we extend the Bridge++ code so that optimized code is available as a new branch, i.e., an alternative to the original code. This paper explains our strategy of implementation and displays application examples to the following architectures and systems: Intel AVX-512 on Xeon Phi Knights Landing, Arm A64FX-SVE on Fujitsu A64FX (Fugaku), NEC SX-Aurora TSUBASA, and GPU cluster with NVIDIA V100.
Machine learning the 2D percolation model
Authors: Bayo Djénabou , Honecker Andreas , Römer Rudolf A.
Published: March 2022

We use deep-learning strategies to study the 2D percolation model on a square lattice. We employ standard image recognition tools with a multi-layered convolutional neural network. We test how well these strategies can characterise densities and correlation lengths of percolation states and whether the essential role of the percolating cluster is recognised.
Characteristics of the growth and composition of AlxGa1-xN/AlN/Si heterostructures with the use of the buffer layer of porous silicon
Authors: Lenshin A , Zolotukhin D , Beltyukov A , Seredin P , Mizerov A
Published: March 2022

The work is concerned with the efficiency of inclusion of the additional layer of por-Si applied as a buffer into the growth technology of AlxGa1-xN/AlN/Si as well as its influence on the morphological parameters and composition of surface of the grown heterostructures. In the course of the study, it was found that the heterostructure grown using a nanoporous por-Si buffer layer on a Si(111) n-type monocrystalline silicon wafer has a more homogeneous structure of the epitaxial layer and its surface morphology.
CVD synthesis of boron nitride from a solid precursor
Authors: Kondrashov I I , Pereyaslavtsev A Y , Obraztsova E D , Rybin M G
Published: March 2022

Here we report on the studies of the controllable synthesis of large area boron nitride films by the resistive heating method on a metal substrate without using a dangerous boron and nitrogen containing gases. In our original home-made CVD setup, we used the copper foil as a metal catalytic substrate. With the solid precursor of ammonia borane, the boron nitride films were synthesized under low pressure conditions and at a growth temperature of about 1000°C. We obtained the films with an area of up to 1x1 cm2 by varying the synthesis parameters. The quality of boron nitride films was characterized using Raman spectroscopy and X-ray spectroscopy.
Theory of electron states in two-dimensional Wigner clusters
Authors: Mahmoodian Mehrdad , Entin M V
Published: March 2022

The results of modeling a finite system of interacting two-dimensional electrons placed at zero temperature into an external parabolic potential well are presented. The structure of the 2D Wigner cluster is found. The distribution functions of interelectron distances and the coordination numbers of internal and external electrons are obtained. The ”string-zigzag” transition is analyzed. The low-temperature specific heat of the system is determined. An electronic Wigner crystal on a sphere is also considered.
Synthesis and study of gas sensitive ZnFe2O4-modified ZnO nanowires
Authors: Aubekerov K , Punegova K N , Sergeenko R , Kuznetsov A , Kondratev V M , Kadinskaya S A , Nalimova S S , Moshnikov V A
Published: March 2022

Currently, new nanostructured materials based on composite metal oxides is of great interest for the development of gas sensors with improved functional characteristics. In this work, zinc oxide nanowires were synthesized by hydrothermal method. Hierarchical ZnO/ZnFe2O4 nanostructures were obtained by immersion of zinc oxide layers in ferrous sulphate aqueous solution. The mechanism of zinc ferrite formation during the interaction of zinc oxide with iron sulphate is considered. The crystal structure of ZnO and ZnO/ZnFe2O4 were studied by Raman spectroscopy. The sensitivity of ZnO and ZnO/ZnFe2O4 nanostructures to isopropyl alcohol vapors was analyzed. It was shown that there is an optimal concentration of ferrous sulphate used to modify zinc oxide nanowires and synthesize ZnO/ZnFe2O4 composite nanostructures.
Resonant Activation of Resistance Switching in Memristors Based on YSZ Films with Au Nanoparticles
Authors: Ryabova M A , Filatov D O , Shenina M E , Koryazhkina M N , Antonov I N , Baranova V N , Gorshkov O N
Published: March 2022

The resonant activation of resistance switching (RS) of a memristor based on an yttria stabilized zirconia (YSZ) film with embedded Au nanoparticles (NPs) was investigated. The switching was made by triangular pulses with high frequency (HF) sinusoid added. A non-monotonous dependence a ratio of the electric current through the memristor in the low resistive state to the current in the high resistive one on the HF sinusoid frequency was found. The effect was explained by a finite electron tunneling time between the Pt electrode and Au NPs. This conclusion was supported by measuring a dependence of HF memristor capacitance on the probing signal frequency.
Simulation of liquid meniscus formation in the ionic liquid electrospray process
Authors: LIU Xinyu , DENG Hanwen , SUN Yiming , KANG Xiaoming
Published: March 2022

Though tremendous efforts have been made to investigate electrospray, some aspects, such as the evolution of the menisci on the micropores of porous emitter tips and the transient response of the meniscus during the polarity alternation, need to be further understood. This paper presents a computation fluid dynamics (CFD) model to describe the meniscus formation in the ionic liquid electrospray process. The CFD model, based on the Taylor–Melcher leaky dielectric fluid theory and the volume of fluid (VOF) method, is validated by experiments. The evolution of the meniscus on the basis of a micropore is presented using two typical ionic liquids, EMI-BF4 and EMI-Im. The influences of the pore size, flow rate and applied voltage on the formation of the meniscus have been studied. Results show that a larger pore is more likely to start emission, and the time consumed for liquid meniscus formation decreases with increasing applied voltage and flow rate. Further, it is found that alternation of polarity does not destroy the structure of the meniscus but retards the formation process, and a faster polarity alteration leads to a shorter delay in meniscus formation time.
Characterization of Occupational Lifting Patterns with Exposure Variation Analysis. Cross-sectional Workplace Study among Blue-Collar Workers
Authors: Jakobsen Markus Due , Sundstrup Emil , Brandt Mikkel , Persson Roger , Andersen Lars L
Published: March 2022

Objectives

To investigate and characterize the influence of sex, age, muscle strength, and cardiovascular fitness on manual lifting patterns using exposure variation analysis (EVA) during a full working day among blue-collar workers.

Methods

Muscular activity (surface electromyography [sEMG]) of the thigh, low-back, and shoulder was measured throughout the working day in 173 employees with manual lifting tasks from 14 workplaces. Relative sEMG loading was expressed as % of maximal voluntary contraction (MVC). As an additional and more practically oriented analysis, calibration of load from standardized box lifts (5, 10, 20, and 30 kg) identified corresponding sEMG values in kg. Using an EVA ‘lifting periods’ of [1 to 5, >5 to 10, >10 to 20, >20 to 30, and >30] kg in time intervals [0 to 0.5, >0.5 to 1, >1 to 2, >2 to 5, >5 to 10, and >10] s were identified. Arm elevation and back inclination were measured using accelerometers.

Results

Females and older workers (≥50 years) primarily used the thighs for lifting and were exposed to more frequent thigh muscle ‘lifting periods’ of varying duration and load and performed more thigh lifts >30 kg and >60% of MVC compared with males and younger workers (P < 0.05). Females had less brief shoulder lifting periods and more work with bent back >30° than the males (P < 0.05), whereas stronger workers performed more work with elevated arm >60° and >90° than workers with low muscle strength (P < 0.05). However, besides a single difference where workers with lower cardiovascular fitness were exposed to more light (1–5 kg) and moderate duration (5–10 s) trapezius loading, the number of lifting periods was not affected by muscle strength nor cardiovascular fitness (P > 0.05).

Conclusions

This EVA demonstrated sex- and age-related differences in exposure to lifting periods involving shoulder and thigh muscles.
Clinical and Virological Characteristics of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) B.1.617.2 (Delta) Variant: A Prospective Cohort Study
Authors: Park Sunghee , Lim So Yun , Kim Ji Yeun , Park Heedo , Lim Joon Seo , Bae Seongman , Kim Jeonghun , Jung Jiwon , Kim Min Jae , Chong Yong Pil , Choi Sang Ho , Lee Sang Oh , Kim Yang Soo , Park Man Seong , Kim Sung Han
Published: March 2022

Background

Data on the clinical and virological characteristics of the Delta variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are limited. This prospective cohort study compared the characteristics of the Delta variant to other variants.

Methods

Adult patients with mild coronavirus disease 2019 (COVID-19) who agreed to daily saliva sampling at a community isolation facility in South Korea between July and August 2021 were enrolled. Scores of 28 COVID-19-related symptoms were recorded daily. The genomic RNA and subgenomic RNA from saliva samples were measured by real-time reverse-transcription polymerase chain reaction (PCR). Cell cultures were performed on saliva samples with positive genomic RNA results.

Results

A total of 141 patients (Delta group, n = 108 [77%]; non-Delta group, n = 33 [23%]) were enrolled. Myalgia was more common in the Delta group than in the non-Delta group (52% vs 27%, P = .03). Total symptom scores were significantly higher in the Delta group between days 3 and 10 after symptom onset. Initial genomic RNA titers were similar between the 2 groups; however, during the late course of disease, genomic RNA titers were higher in the Delta group. Negative conversion of subgenomic RNA was slower in the Delta group (median 9 vs 5 days; P < .001). The duration of viral shedding in terms of positive viral culture was also longer in the Delta group (median 5 vs 3 days; P = .002).

Conclusions

COVID-19 patients infected with the Delta variant exhibited prolonged viable viral shedding with more severe symptoms than those infected with non-Delta variants.