bluuebunny/crossref_metadata_2025 huggingface dataset:
Long-range charge transport in homogeneous and alternating-rigidity chains
Authors: Lai Liang Francisco , Segal Dvira
Published: September 2022

We study the interplay of intrinsic-electronic and environmental factors in long-range charge transport across molecular chains with up to N ∼ 80 monomers. We describe the molecular electronic structure of the chain with a tight-binding Hamiltonian. Thermal effects in the form of electron decoherence and inelastic scattering are incorporated with the Landauer–Büttiker probe method. In short chains of up to ten units, we observe the crossover between coherent (tunneling, ballistic) motion and thermally-assisted conduction, with thermal effects enhancing the current beyond the quantum coherent limit. We further show that unconventional (nonmonotonic with size) transport behavior emerges when monomer-to-monomer electronic coupling is made large. In long chains, we identify a different behavior, with thermal effects suppressing the conductance below the coherent-ballistic limit. With the goal to identify a minimal model for molecular chains displaying unconventional and effective long-range transport, we simulate a modular polymer with alternating regions of high and low rigidity. Simulations show that, surprisingly, while charge correlations are significantly affected by structuring environmental conditions, reflecting charge delocalization, the electrical resistance displays an averaging effect, and it is not sensitive to this patterning. We conclude by arguing that efficient long-range charge transport requires engineering both internal electronic parameters and environmental conditions.
Granular flow around a cylindrical obstacle in an inclined chute
Authors: Cui Xinjun , Harris Matthew , Howarth Martin , Zealey Daisy , Brown Reegan , Shepherd Jonny
Published: September 2022

Shock waves and granular vacua are important phenomena for studying the behavior of granular materials due to the dramatic change in flow properties across shock wave and the particle-free feature at the boundary of granular vacuum. In this paper, we use experiment and numerical simulation to study the granular free-surface flow past a cylindrical obstacle in an inclined chute, where the time-dependent development of the granular flow impacting the obstacle is analyzed at both microscopic and macroscopic scales using the discrete element method (DEM) and the depth-averaged granular model, respectively. Using high-speed camera results as a benchmark solution, the shock solutions are compared between experiment and simulation. The DEM simulation shows better agreement for its shock formation as it is capable of capturing solid, liquid, and gas behaviors for the shock region, while the depth-averaged model provides closer and simpler agreement for the jump solution across the shock. It is shown from the experiment and simulation that the granular shock wave can give rise to a solid–liquid–gas behavior following the propagation of the flow around the obstacle, where, at the front of the obstacle, the shock region can be regarded as a solid regime as the flow becomes stationary during the primary course of the granular flow. With the flow propagating to the downstream, the shock region extends significantly and exhibits strong liquid and gas behavior. Another mixed liquid and gas behavior of granular flow is also observed following the appearance of the granular vacuum, where a localized μ(I)-rheology is shown to be effective in resolving the vacuum boundary in the numerical simulation.
Understanding efficiency improvements of betavoltaic batteries based on 4H-SiC, GaN, and diamond
Authors: Zheng Renzhou , Lu Jingbin , Wang Yu , Chen Ziyi , Zhang Xue , Li Xiaoyi , Liang Lei , Qin Li , Zeng Yugang , Chen Yongyi , Liu Yumin
Published: September 2022

Wide-bandgap semiconductors are more advantageous for betavoltaic batteries due to their high conversion efficiency and strong radiation resistance. However, there has been little comprehensive analysis of how wide-bandgap semiconductors lead to efficiency improvements. In this work, we proposed a simulation model to predict the output performance of betavoltaic batteries based on 4H-SiC, hexagonal-GaN, and diamond, in which the Monte Carlo code and COMSOL Multiphysics software were combined. The energy deposition of a 63Ni source in semiconductors and the electrical characteristics of p–n junctions were investigated and compared. Our simulation results showed that the mass density and atomic number of semiconductor materials will cause the difference in energy deposition distribution, further leading to the different electron–hole pair generation rates. Then, the internal efficiency of batteries is co-determined by the energy band structure, depletion region width, built-in potential barrier, and minority carrier lifetime. The batteries based on wide-bandgap semiconductors can achieve the larger open-circuit voltage, further leading to higher efficiency. Additionally, to optimize the energy converter structure, the output parameters were calculated with a variation of doping concentrations and thicknesses of each region. Under the irradiation of a 63Ni source, the diamond-based battery with a p–n junction structure has the highest internal efficiency of 31.3%, while the GaN-based battery has the lowest one (16.8%), which can be attributed to the larger carrier recombination rate.
Diffusio-osmosis of oil–CO2 mixture in inorganic nanopores
Authors: Zhang Hongwei , Moh Do Yoon , Wang Shihao , Qiao Rui
Published: September 2022

Diffusio-osmosis is the interfacial transport induced by solute density gradient and plays an essential role in many micro/nanofluidic systems. Here, we report the molecular dynamics simulations of the diffusio-osmosis of oil–CO2 mixture in silica and calcite nanopores. We show that, under the high solute (CO2) density considered, although the enrichment of CO2 near calcite walls is substantially higher than that near silica walls, the diffusio-osmosis in calcite pores is only marginally stronger. This phenomenon is attributed to the significantly different molecular structures and hydrodynamic properties of interfacial fluids in the two pores caused by the CO2 adsorption on their walls, which is in turn traced to the different physical chemistry of the silica and calcite walls. Using continuum simulations parameterized by the diffusio-osmosis characteristics obtained in our molecular modeling, we show that, for the oil transport through slit pores driven by pressurized CO2, the diffusio-osmosis becomes important compared to the Poiseuille flow when the pore width decreases below a few tens of nanometers and its significance compared to the Poiseuille flow increases quadratically as the pore width decreases.
The dynamics of cylinder-wake/boundary-layer interaction revealed by turbulent transports
Authors: Li Jiang-Hua , Wang Bo-Fu , Qiu Xiang , Wu Jian-Zhao , Zhou Quan , Fu Shi-Xiao , Liu Yu-Lu
Published: September 2022

The flow past a cylinder near a plane wall for small gap ratios (G/D=0.1, 0.3, and 0.9) and fixed ReD = 1000 is numerically studied. The fundamental flow features are characterized by the instantaneous and mean fields. Then, the dynamics of cylinder-wake/boundary-layer interaction are revealed by the turbulent momentum transport and kinetic energy production. The turbulent fluctuations caused by the secondary vortex (SV) (at G/D=0.3, 0.9) and the novel tertiary vortex (TV) (at G/D=0.9) can be observed in the distributions of Reynolds stresses. For G/D=0.1 and G/D=0.3, the wake/boundary-layer interaction is dominated by ejection and sweep events, which are related to the generation of the hairpin vortex. These two bursting events lead to the momentum transport between the high- and low-speed sides. For G/D=0.9, the ejection event is not found in the interaction region because the head of the hairpin vortex is entrained into the wake. The upper roller (RU) helps to transport high-momentum fluid toward the wall in this case, although it does not take part in the interaction directly. The shedding of RU, the lower roller (RL), SV (at G/D=0.3 and 0.9), and KH (Kelvin–Helmholtz) vortex (at G/D=0.1) and the generation of the hairpin vortex are crucial to turbulent kinetic energy (TKE) production. The RU, KH vortex, and SV transfer ⟨u′u′⟩ out to ⟨v′v′⟩ and ⟨w′w′⟩ resulting redistribution of the TKE. While RL, surviving for a shorter time, transfers ⟨v′v′⟩ out to ⟨u′u′⟩ and ⟨w′w′⟩, helping explain why it disappears quickly, TV only transfers out ⟨v′v′⟩ out to ⟨u′u′⟩, and its TKE comes from other terms rather than the production term. The redistribution of TKE due to the generation of the hairpin vortex can result in the slower growth rate of the secondary disturbance growth stage, promoting the wall boundary layer transition.
Virial equation of state as a new frontier for computational chemistry
Authors: Schultz Andrew J. , Kofke David A.
Published: September 2022

The virial equation of state (VEOS) provides a rigorous bridge between molecular interactions and thermodynamic properties. The past decade has seen renewed interest in the VEOS due to advances in theory, algorithms, computing power, and quality of molecular models. Now, with the emergence of increasingly accurate first-principles computational chemistry methods, and machine-learning techniques to generate potential-energy surfaces from them, VEOS is poised to play a larger role in modeling and computing properties. Its scope of application is limited to where the density series converges, but this still admits a useful range of conditions and applications, and there is potential to expand this range further. Recent applications have shown that for simple molecules, VEOS can provide first-principles thermodynamic property data that are competitive in quality with experiment. Moreover, VEOS provides a focused and actionable test of molecular models and first-principles calculations via comparison to experiment. This Perspective presents an overview of recent advances and suggests areas of focus for further progress.
Does toxicity test variability support bioavailability model predictions being within a factor of 2?
Authors: Price Gwilym A. V. , Stauber Jenny L. , Stone Sarah , Koppel Darren J. , Holland Aleicia , Jolley Dianne
Published: September 2022

Environmental context Having appropriate and robust models used for developing water quality guidelines is critical for sound environmental management. Methods used to validate models have only been demonstrated appropriate for a small portion of data types used in these models. This study has found that models using certain data types would be more appropriately validated using alternative evaluation criteria. This study serves as an important reference for developing and evaluating robust models. Rationale Bioavailability-based toxicity models for metals often have performance assessed by whether it can predict toxicity data within a factor of 2 of their paired observed toxicity data. This method has only been verified for median effect values (EC50) for acute fish and daphnia data, however toxicity models have been developed for a much broader range of effect levels (i.e. EC10/EC20) and species (e.g. microalga). This study tested whether the factor-of-2 rule is appropriate for a wider range of organisms and effect concentrations than previously studied. Methodology Toxicity estimate data from repeated tests conducted under the same conditions were collated to assess variation in results and compare this variation to a range of 4 (a factor of 2 above and below the mean) and a range of 9 (a factor of 3 above and below the mean) to assess if a factor-of-3 rule may be more appropriate for some species and effect levels. Results and discussion Overall, the factor-of-2 rule is broadly applicable for metal toxicity to a range of species for EC50 data. The EC10 datasets highlighted that larger variability exists in low effect levels and supported the use of a factor-of-3 rule, while the either the factor-of-2 or factor-of-3 rule could be applied to microalgae. The level of performance evaluation chosen may depend on the application of the bioavailability model. This study also found that while repeated toxicity test data is routinely generated, it is rarely published. Publication of such data would enable expansion of the present study to include inter-laboratory comparisons, an important consideration as most bioavailability models are based on data pooled from multiple sources.
Effects of age composition of Pacific bluefin tuna on their spatiotemporal distribution of active breeding in the south-western North Pacific and on its recruitment strength
Authors: Ishihara Taiki , Shimose Tamaki , Uematsu Yuki
Published: September 2022

Context The south-western North Pacific is one of the main spawning grounds of the Pacific bluefin tuna (Thunnus orientalis) and is targeted by Japanese longline fisheries. Aims This study evaluated the influence of age composition of spawning groups in this area on the strength of recruitment through the spatiotemporal distribution of active breeding. Methods The variation in the recent year-class strength in the area was estimated on the basis of the otolith age estimation and catch data from 2007 to 2016. Key results In the age–frequency distribution, 9 years was the most frequent age class. The instantaneous total mortality after 9 years of age was 0.32. Conclusions On the basis of catch locations and age estimation results, the bias toward young individuals influenced the spatiotemporal pattern of active breeding to shifts to higher latitudes and earlier breeding. In this area, the abundance of the main spawning group (9- and 10-year-old fish) may affect the recruitment of 0-year-old fish, and the older fish are considered to serve as a ‘seed bank’. Implications These results are expected to contribute to the development of appropriate management strategies for spawning stocks in the area and demonstrate the magnitude of the influence of age composition on population fluctuations.
Simulating respiratory disease transmission within and between classrooms to assess pandemic management strategies at schools
Authors: Endo (遠藤彰) Akira ,   CMMID COVID-19 Working Group, Uchida (内田満夫) Mitsuo , Liu (刘扬) Yang , Atkins Katherine E. , Kucharski Adam J. , Funk Sebastian , Abbas Kaja , van Zandvoort Kevin , Bosse Nikos I , Waterlow Naomi R , Tully Damien C , Meakin Sophie R , Quaife Matthew , Russell Timothy W , Jit Mark , Foss Anna M , Rosello Alicia , Quilty Billy J , Prem Kiesha , Knight Gwenan M , Abbott Sam , Klepac Petra , Brady Oliver , Pearson Carl A B , Medley Graham , Clifford Samuel , Jarvis Christopher I , Munday James D , Sandmann Frank G , Sun Fiona Yueqian , Jombart Thibaut , Hellewell Joel , Gibbs Hamish P , Barnard Rosanna C , Eggo Rosalind M , Gimma Amy , Williams Jack , Davies Nicholas G. , Nightingale Emily S , Procter Simon R , Edmunds W John , Showering Alicia , Lowe Rachel , Sherratt Katharine , Villabona-Arenas C Julian , Simons David , Chan Yung-Wai Desmond , Flasche Stefan
Published: September 2022

The global spread of coronavirus disease 2019 (COVID-19) has emphasized the need for evidence-based strategies for the safe operation of schools during pandemics that balance infection risk with the society’s responsibility of allowing children to attend school. Due to limited empirical data, existing analyses assessing school-based interventions in pandemic situations often impose strong assumptions, for example, on the relationship between class size and transmission risk, which could bias the estimated effect of interventions, such as split classes and staggered attendance. To fill this gap in school outbreak studies, we parameterized an individual-based model that accounts for heterogeneous contact rates within and between classes and grades to a multischool outbreak data of influenza. We then simulated school outbreaks of respiratory infectious diseases of ongoing threat (i.e., COVID-19) and potential threat (i.e., pandemic influenza) under a variety of interventions (changing class structures, symptom screening, regular testing, cohorting, and responsive class closures). Our results suggest that interventions changing class structures (e.g., reduced class sizes) may not be effective in reducing the risk of major school outbreaks upon introduction of a case and that other precautionary measures (e.g., screening and isolation) need to be employed. Class-level closures in response to detection of a case were also suggested to be effective in reducing the size of an outbreak.
ISL1 is necessary for auditory neuron development and contributes toward tonotopic organization
Authors: Filova Iva , Pysanenko Kateryna , Tavakoli Mitra , Vochyanova Simona , Dvorakova Martina , Bohuslavova Romana , Smolik Ondrej , Fabriciova Valeria , Hrabalova Petra , Benesova Sarka , Valihrach Lukas , Cerny Jiri , Yamoah Ebenezer N. , Syka Josef , Fritzsch Bernd , Pavlinkova Gabriela
Published: September 2022

A cardinal feature of the auditory pathway is frequency selectivity, represented in a tonotopic map from the cochlea to the cortex. The molecular determinants of the auditory frequency map are unknown. Here, we discovered that the transcription factor ISL1 regulates the molecular and cellular features of auditory neurons, including the formation of the spiral ganglion and peripheral and central processes that shape the tonotopic representation of the auditory map. We selectively knocked out
Isl1
in auditory neurons using

Neurod1
Cre

strategies. In the absence of
Isl1
, spiral ganglion neurons migrate into the central cochlea and beyond, and the cochlear wiring is profoundly reduced and disrupted. The central axons of
Isl1
mutants lose their topographic projections and segregation at the cochlear nucleus. Transcriptome analysis of spiral ganglion neurons shows that
Isl1
regulates neurogenesis, axonogenesis, migration, neurotransmission-related machinery, and synaptic communication patterns. We show that peripheral disorganization in the cochlea affects the physiological properties of hearing in the midbrain and auditory behavior. Surprisingly, auditory processing features are preserved despite the significant hearing impairment, revealing central auditory pathway resilience and plasticity in
Isl1
mutant mice. Mutant mice have a reduced acoustic startle reflex, altered prepulse inhibition, and characteristics of compensatory neural hyperactivity centrally. Our findings show that ISL1 is one of the obligatory factors required to sculpt auditory structural and functional tonotopic maps. Still, upon
Isl1
deletion, the ensuing central plasticity of the auditory pathway does not suffice to overcome developmentally induced peripheral dysfunction of the cochlea.
L2 acquisition of the Chinese plural marker -men by English and Korean speakers
Authors: Su Jiajia
Published: September 2022

This article investigates the L2 acquisition of the Chinese plural maker -men by English and Korean speakers within the framework of the Feature Reassembly Hypothesis (FRH) (Lardiere, 2009). The Chinese plural suffix -men, the Korean plural suffix -tul, and the English plural suffix -s share some properties and differ on others. Thirty-two English-speaking learners and thirty-five Korean-speaking learners of Chinese of advanced and intermediate proficiency were tested using a truth value judgment task and a grammaticality judgment task. Results show that: (i) all the L2 groups have acquired the target feature set of -men (i.e., [plural, specific, human]); (ii) the two English groups and the advanced Korean group but not the intermediate Korean group have acquired the conditions on the overt realization of -men (i.e., optionality with demonstratives and prohibition with classifiers). The results are consistent with the FRH: differences in how features are assembled in lexical items and differences in conditions on feature realization between the L1 and L2 lead to acquisition difficulty; such difficulty can be overcome, though native-like performance is not guaranteed.
Tensin3 interaction with talin drives the formation of fibronectin-associated fibrillar adhesions
Authors: Atherton Paul , Konstantinou Rafaella , Neo Suat Peng , Wang Emily , Balloi Eleonora , Ptushkina Marina , Bennett Hayley , Clark Kath , Gunaratne Jayantha , Critchley David , Barsukov Igor , Manser Edward , Ballestrem Christoph
Published: September 2022

The formation of healthy tissue involves continuous remodeling of the extracellular matrix (ECM). Whilst it is known that this requires integrin-associated cell-ECM adhesion sites (CMAs) and actomyosin-mediated forces, the underlying mechanisms remain unclear. Here, we examine how tensin3 contributes to the formation of fibrillar adhesions (FBs) and fibronectin fibrillogenesis. Using BioID mass spectrometry and a mitochondrial targeting assay, we establish that tensin3 associates with the mechanosensors such as talin and vinculin. We show that the talin R11 rod domain binds directly to a helical motif within the central intrinsically disordered region (IDR) of tensin3, whilst vinculin binds indirectly to tensin3 via talin. Using CRISPR knock-out cells in combination with defined tensin3 mutations, we show (i) that tensin3 is critical for the formation of α5β1-integrin FBs and for fibronectin fibrillogenesis, and (ii) the talin/tensin3 interaction drives this process, with vinculin acting to potentiate it.
The miR-181 family regulates colonic inflammation through its activity in the intestinal epithelium
Authors: Jimenez Monica T. , Clark Megan L. , Wright Jasmine M. , Michieletto Michaël F. , Liu Suying , Erickson Isabel , Dohnalova Lenka , Uhr Giulia T. , Tello-Cajiao John , Joannas Leonel , Williams Adam , Gagliani Nicola , Bewtra Meenakshi , Tomov Vesselin T. , Thaiss Christoph A. , Henao-Mejia Jorge
Published: September 2022

The intestinal epithelium is a key physical interface that integrates dietary and microbial signals to regulate nutrient uptake and mucosal immune cell function. The transcriptional programs that regulate intestinal epithelial cell (IEC) quiescence, proliferation, and differentiation have been well characterized. However, how gene expression networks critical for IECs are posttranscriptionally regulated during homeostasis or inflammatory disease remains poorly understood. Herein, we show that a conserved family of microRNAs, miR-181, is significantly downregulated in IECs from patients with inflammatory bowel disease and mice with chemical-induced colitis. Strikingly, we showed that miR-181 expression within IECs, but not the hematopoietic system, is required for protection against severe colonic inflammation in response to epithelial injury in mice. Mechanistically, we showed that miR-181 expression increases the proliferative capacity of IECs, likely through the regulation of Wnt signaling, independently of the gut microbiota composition. As epithelial reconstitution is crucial to restore intestinal homeostasis after injury, the miR-181 family represents a potential therapeutic target against severe intestinal inflammation.
Intertwiner entanglement excitation and holonomy operator
Authors: Chen Qian , Livine Etera R
Published: September 2022

In the loop quantum gravity framework, spin network states carry entanglement between quantum excitations of the geometry at different space points. This intertwiner entanglement is gauge-invariant and comes from quantum superposition of spins and intertwiners. Bipartite entanglement can be interpreted as a witness of distance, while multipartite entanglement reflects the curvature of the quantum geometry. The present work investigates how the bipartite and multipartite intertwiner entanglement changes under the action of the holonomy operator, which is the basic building block of loop quantum gravity’s dynamics. We reveal the relation between entanglement excitation and the dispersion of the holonomy operator. This leads to a new interesting connection between bulk geometry and boundary observables via the dynamics of entanglement.
Two-photon IR pumped UV–Vis transient absorption spectroscopy of Dirac fermions in the topological insulator Bi2Se3
Authors: Glinka Yuri D , He Tingchao , Sun Xiao Wei
Published: September 2022

It is often taken for granted that in pump-probe experiments on the topological insulator (TI) Bi2Se3 using IR pumping with a commercial Ti:sapphire laser [∼800 nm (1.55 eV photon energy)], the electrons are excited in the one-photon absorption regime, even when pumped with absorbed fluences in the mJ cm−2 range. Here, using UV–Vis transient absorption (TA) spectroscopy, we show that even at low-power Infrared (IR) pumping with absorbed fluences in the μJ cm−2 range, the TA spectra of the TI Bi2Se3 extend across a part of the UV and the entire visible region. This observation suggests unambiguously that the two-photon pumping regime accompanies the usual one-photon pumping regime even at low laser powers applied. We attribute the high efficiency of two-photon pumping to the giant nonlinearity of Dirac fermions in the Dirac surface states (SS). On the contrary, one-photon pumping is associated with the excitation of bound valence electrons in the bulk into the conduction band. Two mechanisms of absorption bleaching were also revealed since they manifest themselves in different spectral regions of probing and cause the appearance of three different relaxation dynamics. These two mechanisms were attributed to the filling of the phase-space in the Dirac SS and bulk states, followed by the corresponding Pauli blocking.
Traceable calibration of a broadband seismometer down to 5 mHz
Authors: Shimoda Tomofumi , Kokuyama Wataru , Nozato Hideaki
Published: September 2022

Broadband seismometers have been widely employed in geophysical observation and disaster prevention. To ensure the reliability of the measurement, traceable calibration of their sensitivities following ISO 16063-11 down to 8 mHz is required. However, the calibration accuracy generally degrades below 0.1 Hz due to tilt-coupling error. In this paper, two tilt-coupling correction methods are investigated: one is a dynamic tilt measurement method using an autocollimator, and the other is a comparison method using a reference accelerometer. These methods were introduced to the primary calibration system to calibrate a seismometer between 5 mHz and 200 Hz. As a result, the tilt-coupling error was corrected with an estimated uncertainty of less than 2% at 5 mHz, and the bandpass response of the seismometer sensitivity was confirmed with the traceable method.
Analysis of electromagnetic-thermal coupling braking properties of combined electromagnetic friction and shape memory alloy brake
Authors: Gong Hang , Xiong Yang , Huang Jin
Published: September 2022

To address the problems of severe heat generation and poor stability of traditional electromagnetic friction brakes, combined electromagnetic friction and shape memory alloy (SMA) braking method is proposed. This novel brake solves the traditional electric brake thermal decay problem based on the temperature sensing ability of SMA, which improves its working stability in a high-temperature environment. Based on Ampere’s law of magnetic field, the relationship between current and electromagnetic force was established, and the equation of electromagnetic force braking torque was derived. Based on the thermodynamic model of a SMA, the relationship between the frictional torque of SMA and parameters such as temperature, squeezing pressure, and structure size was established. The magnetic and thermal fields of this brake were analyzed by the finite element method to obtain the magnetic field distribution and the magnitude of electromagnetic force at different currents and to derive the temperature distribution of the brake at different currents. The brake was analyzed by the SMA squeezing pressure test platform and the braking performance test platform. The results show that the electromagnetic torque grows non-linearly with temperature, and the squeezing force generated by the SMA spring increases with temperature. When the current is 0.7 A, the braking torque generated by electromagnetism is 170.3 N m, while the maximum braking torque generated by the combination of electromagnetism and SMA is 212.6 N m, which is 20.4% higher than that of the traditional electromagnetic friction brake. This novel brake improves braking performance and ensures stable braking performance under temperature rise.
Reducing cross-field demagnetization of superconducting stacks by soldering in pairs
Authors: Dadhich Anang , Li Shuo , Solovyov Mykola , Šouc Ján , Mošat’ Marek , Pardo Enric
Published: September 2022

Superconducting stacks can be used as strong permanent magnets in several applications. One of their uses is to build light and compact superconducting motors for aviation, where these magnets can be used in the rotor, but they can demagnetize quickly in the presence of cross fields. In this article, we propose a new configuration of soldered stacks face-to-face, which can be constructed by relatively simple joining techniques. Based on numerical modeling of the cross-field demagnetization of stacks of two and 16 tapes, we show that such a sample can withstand around twice as high ripple field amplitudes than isolated stacks. This is due to the increase in the parallel penetration field by around a factor 2. For cross-field amplitudes below this value, a soldered stack can retain higher permanent magnetization than isolated stacks. This method of reducing cross-field demagnetization does not decrease the power or torque rating of a motor, compared to other strategies like the increase in the gap between rotor and stator.
Optimal navigation of microswimmers in complex and noisy environments
Authors: Piro Lorenzo , Mahault Benoît , Golestanian Ramin
Published: September 2022

We design new navigation strategies for travel time optimization of microscopic self-propelled particles in complex and noisy environments. In contrast to strategies relying on the results of optimal control theory or machine learning approaches, implementation of these protocols can be done in a semi-autonomous fashion, as it does not require control over the microswimmer motion via external feedback loops. Although the strategies we propose rely on simple principles, they show arrival time statistics strikingly close to optimality, as well as performances that are robust to environmental changes and strong fluctuations. These features, as well as their applicability to more general optimization problems, make these strategies promising candidates for the realization of optimized semi-autonomous navigation.
A measure of complexity for axial self-gravitating static fluids
Authors: Farwa U , Yousaf Z , Bhatti M Z
Published: September 2022

One of the feasible potential candidates for illustrating the accelerating expansion of the cosmos can be taken through the notion of modified gravity. Within the context of metric f(R) gravity, the contribution of this work features a better understanding of complexity factors for anisotropic static fluid composition in axially symmetric spacetime. This is a generalization of the work done by Herrera et al (2019, Phys. Rev. D
99, 044 049). We formulate generalized dynamical and field equations for anisotropic sources in our analysis. We will compute three distinct complexity factors (Y

TF1, Y

TF2, Y

TF3) after incorporating structure scalars via orthogonal breakdown of the curvature tensor. The differential equations for the conformal tensor are assessed in terms of these complexity factors for the physical illustration. It is inferred that all these factors vanish for the matter spheroid provided with energy homogeneity and isotropic pressure. Nonetheless, the vanishing of these factors might be observed in different scenarios. This happened because energy inhomogeneity and pressure anisotropy cancel out each other in the description of complexity factors. Certain exact solutions of this nature have been reported and studied. All of the outcomes would reduce to general relativity within usual limits.
Photonic crystal for efficiency enhancement of the semitransparent organic solar cells
Authors: Ahmadi Neda
Published: September 2022

We have designed the semitransparent organic solar cells (STOSCs) with two fullerene materials as active layers. we have used the two-dimensional(2D) photonic crystals (PCs) inside the active layer and investigated the optical and electrical parameters of solar cells. We have utilized the Finite-difference time-domain (FDTD) method for our simulation and have shown the effect of 2D photonic crystals in transmission, absorption, short-circuit current density (Jsc), generation rate, and electrical current. We also found that the polymer donorpoly[2,60-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b[dithiophene]-alt-[3-fluoro-2[(2-ethylhexyl)carbonyl]thieno[3,4-b[thiophenediyl] (PTB7- Th) with the visible absorbing fullerene acceptor [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), PTB7-Th:PC71BM, can be a better choice as an active layer compared with the poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methylester (PCBM), P3HT:PCBM. This study can be useful for light management in STOSCs.
Realistic photon-number resolution in generalized Hong-Ou-Mandel experiment
Authors: Len V Ye , Byelova M M , Uzunova V A , Semenov A A
Published: September 2022

We consider realistic photodetection in a generalization of the Hong-Ou-Mandel experiment to the multimode case. The basic layout of this experiment underlies boson sampling—a promising model of nonuniversal quantum computations. Peculiarities of photocounting probabilities in such an experiment witness important nonclassical properties of electromagnetic field related to indistinguishability of boson particles. In practice, these probabilities are changed from their theoretical values due to the imperfect ability of realistic detectors to distinguish numbers of bunched photons. We derive analytical expressions for photocounting distributions in the generalized Hong-Ou-Mandel experiment for the case of realistic photon-number resolving (PNR) detectors. It is shown that probabilities of properly postselected events are proportional to probabilities obtained for perfect PNR detectors. Our results are illustrated with examples of arrays of on/off detectors and detectors affected by a finite dead time.
A prototype biospecklemeter for microbiological analysis: a starting point for a potential digital-image laser antibiotic susceptibility test
Authors: Grassi Hilda Cristina , Andrades Efrén De Jesús , Lobo María Lorena , Andrades Jesús Enrique
Published: September 2022

This work describes the design and construction of a low-cost prototype biospecklemeter. In this first report of its applications a microbiological analysis was performed. The relationship between microorganism density, motility and biospeckle activity was evaluated. The aim is to produce a device for research and for student use. The biospecklemeter was constructed on an antivibration table with low-cost materials and accessories and assayed using different microorganisms grown in Mueller–Hinton broth and/or agar as well as urine samples. Three lasers were installed (blue, green and red) as well as two webcams and a charge-coupled device camera. The samples were carried within the wells of a VDRL plate and 5–30 s videos or photographs of reflected light were taken. Video or photo processing was carried out using the method of temporal differences (ImageJ) or generalized differences (ImageDP). It was possible to establish a direct relationship between spectrophotometric absorption, the microbial count and the biospeckle intensity; changes in motility and the effect of antibiotics on bacterial laboratory samples as well as on urine samples were also detected. Finally, with this method colonies of different microorganisms on Mueller–Hinton agar were studied.
Solid–gas interface thermal conductance for the thermal barrier coating with surface roughness: The confinement effect
Authors: Zhao Xue , Jiang Jin-Wu
Published: September 2022

The yttria-stabilized zirconia (YSZ) is a famous thermal barrier coating material to protect hot-end components of an engine. As a characteristic feature of the YSZ, the surface roughness shall play an important role in the interface thermal conductance between the YSZ and gas, considering that the gas is typically at an extremely high temperature. We investigate the effect of the surface roughness on the thermal conductance of the YSZ–gas interface with surface roughness described by nanoscale pores on the surface of the YSZ. We reveal two competitive mechanisms related to the microstructure of the pore, i.e., the actual contact area effect and the confinement effect. The increase of the pore depth will enlarge the actual contact area between the YSZ and gas, leading to enhancement of the solid–gas interface thermal conductance. In contrast to the positive actual contact area effect, the geometry-induced confinement effect greatly reduces the interface thermal conductance. These findings shall offer some fundamental understandings for the microscopic mechanisms of the YSZ–gas interface thermal conductance.
Complete hyperentangled Greenberger-Horne-Zeilinger state analysis for polarization and time-bin hyperentanglement
Authors: Zeng Zhi
Published: September 2022

We present an efficient scheme for the complete analysis of hyperentangled Greenberger–Horne–Zeilinger (GHZ) state in polarization and time-bin degrees of freedom with two steps. Firstly, the polarization GHZ state is distinguished completely and nondestructively, resorting to the controlled phase flip (CPF) gate constructed by the cavity-assisted interaction. Subsequently, the time-bin GHZ state is analyzed by using the preserved polarization entanglement. With the help of CPF gate and self-assisted mechanism, our scheme can be directly generalized to the complete N-photon hyperentangled GHZ state analysis, and it may have potential applications in the hyperentanglement-based quantum communication.
Hall conductance of a non-Hermitian two-band system with k-dependent decay rates
Authors: Wang Junjie , Li Fude , Yi Xuexi
Published: September 2022

Two-band model works well for Hall effect in topological insulators. It turns out to be non-Hermitian when the system is subjected to environments, and its topology characterized by Chern numbers has received extensive studies in the past decades. However, how a non-Hermitian system responses to an electric field and what is the connection of the response to the Chern number defined via the non-Hermitian Hamiltonian remains barely explored. In this paper, focusing on a k-dependent decay rate, we address this issue by studying the response of such a non-Hermitian Chern insulator to an external electric field. To this aim, we first derive an effective non-Hermitian Hamiltonian to describe the system and give a specific form of k-dependent decay rate. Then we calculate the response of the non-Hermitian system to a constant electric field. We observe that the environment leads the Hall conductance to be a weighted integration of curvature of the ground band and hence the conductance is no longer quantized in general. And the environment induces a delay in the response of the system to the electric field. A discussion on the validity of the non-Hermitian model compared with the master equation description is also presented.
Interface-induced topological phase and doping-modulated bandgap of two-dimensioanl graphene-like networks
Authors: Yang Ningjing , Yang Hai , Jin Guojun
Published: September 2022

Biphenylene is a new topological material that has attracted much attention recently. By amplifying its size of unit cell, we construct a series of planar structures as homogeneous carbon allotropes in the form of polyphenylene networks. We first use the low-energy effective model to prove the topological three periodicity for these allotropes. Then, through first-principles calculations, we show that the topological phase has the Dirac point. As the size of per unit cell increases, the influence of the quaternary rings decreases, leading to a reduction in the anisotropy of the system, and the Dirac cone undergoes a transition from type II to type I. We confirm that there are two kinds of non-trivial topological phases with gapless and gapped bulk dispersion. Furthermore, we add a built-in electric field to the gapless system by doping with B and N atoms, which opens a gap for the bulk dispersion. Finally, by manipulating the built-in electric field, the dispersion relations of the edge modes will be transformed into a linear type. These findings provide a hopeful approach for designing the topological carbon-based materials with controllable properties of edge states.
Global gyrokinetic simulations of electrostatic microturbulent transport using kinetic electrons in LHD stellarator
Authors: Singh Tajinder , Nicolau Javier H. , Lin Zhihong , Sharma Sarveshwar , Sen Abhijit , Kuley Animesh
Published: September 2022

Global gyrokinetic simulations of ion temperature gradient (ITG) and trapped electron mode (TEM) in the LHD stellarator are carried out using the gyrokinetic toroidal code (GTC) with kinetic electrons. ITG simulations show that kinetic electron effects increase the growth rate by more than 50% and more than double the turbulent transport levels compared with simulations using adiabatic electrons. Zonal flow dominates the saturation mechanism in the ITG turbulence. Nonlinear simulations of the TEM turbulence show that the main saturation mechanism is not the zonal flow but the inverse cascade of high to low toroidal harmonics. Further nonlinear simulations with various pressure profiles indicate that the ITG turbulence is more effective in driving heat conductivity whereas the TEM turbulence is more effective for particle diffusivity.
A SECI Method Based on Improved YOLOv4 for Traffic Sign Detection and Recognition
Authors: Zuo Jing , Han Fengchun , Meng Qingda
Published: September 2022

Traffic sign detection and recognition (TSDR) has become extraordinarily significant in autonomous driving. To trade-off between high accuracy and fast detection speed, a four-stage method, Selecting-Extracting-Cleaning and Identifying (SECI) based on improved algorithm of You Only Look Once version 4 (YOLOv4) is proposed, including selecting the anchor boxes of traffic signs by using k-means++ clustering algorithm, extracting traffic sign features by using subsampled layer, cleaning the redundant information by amending structure of the Spatial Pyramid Pooling (SPP) and identifying traffic signs by adding auxiliary branches and multi-scale feature fusion. Compared to the origin YOLOv4, the results show that, the SECI method improves the mean average precision (mAP) by 6.71%, the detection speed is improved by 37%, and the F1 score is improved by 13%.
Multi-sensor Resource Management and Intelligent Target Tracking Strategy Generation and Evaluation Based on Ant Colony Algorithm
Authors: Ma Chen , Shang Xia , Wan Yujun , Du Wei , ZhuanSun Shaoshuai
Published: September 2022

This paper studies the multi-sensor resource management and intelligent tracking strategy generation for different targets. Firstly, the multi-sensor resource management methods are analyzed and compared with each other to specify the planning and information theories as the basis for this research. Then, a functional model is established according to the sensor resource updates, target visibility analysis, sensor performance analysis and sensor-to-target assignments. And the multi-sensor intelligent target tracking workflow is designed based on the function model. Thirdly, the corresponding multi-sensor intelligent target tracking strategy generation is designed based on ant colony algorithm. Finally, the evaluation analysis on the strategy generation is completed. This study provides a reference for the future studies on multi-sensor intelligent target tracking and multi-sensor system design.
Functional mobility decline and incident mild cognitive impairment and early dementia in community-dwelling older adults: the Singapore Longitudinal Ageing Study
Authors: Ng Tze Pin , Lee Tih Shih , Lim Wee Shiong , Chong Mei Sian , Yap Philip , Cheong Chin Yee , Rawtaer Iris , Liew Tau Ming , Gwee Xinyi , Gao Qi , Yap Keng Bee
Published: September 2022

Background

Motor and gait disturbances are evident in early Alzheimer and non-Alzheimer dementias and may predict the likelihood of mild cognitive impairment (MCI) or progression to dementia.

Objective

We investigated the Timed-Up-and-Go (TUG) measure of functional mobility in predicting cognitive decline and incident MCI or early dementia (MCI–dementia).

Design

Prospective cohort study with 4.5 years follow-up.

Setting

Population based.

Participants

2,544 community-dwelling older adults aged 55+ years.

Methods

Participants with baseline data on TUG, fast gait speed (GS), knee extension strength (KES) and performance-oriented mobility assessment (POMA) gait and balance were followed up for cognitive decline (Mini-Mental State Exam; MMSE drop of ≥2, among 1,336 dementia-free participants) and incident MCI–dementia (among 1,208 cognitively normal participants). Odds ratio (OR) and 95% confidence intervals (95% CI) were adjusted for age, sex, education, smoking, physical, social and productive activity, multi-morbidity, metabolic syndrome and MMSE.

Results

Per standard deviation increase in TUG, POMA, GS and KES were significantly associated with incident MCI–dementia: TUG (OR = 2.84, 95% CI = 2.02–3.99), GS (OR = 2.17, 95% CI = 1.62–2.91), POMA (OR = 1.88, 95% CI = 1.22–2.92) and KES (OR = 1.52, 95% CI = 1.15–2.02). Adjusted OR remained significant only for TUG (OR = 1.52, 95% CI = 1.01–2.31) and GS (OR = 1.53, 95% CI = 1.08–2.16). Areas under the curve (AUC) for TUG (AUC = 0.729, 95% CI = 0.671–0.787) were significantly greater than GS (AUC = 0.683, 95% CI = 0.619–0.746), KES (AUC = 0.624, 95% CI = 0.558–0.689) and POMA (AUC = 0.561, 95% CI = 0.485–0.637). Similar associations with cognitive decline were significant though less pronounced, and adjusted ORs remained significant for TUG, GS and POMA.

Conclusion

Functional mobility decline precedes incident MCI and early dementia. The TUG appears to be especially accurate in predicting the future risks of adverse cognitive outcomes.

Trial Registration

ClinicalTrials.gov NCT03405675. Registered 23 January 2018 (retrospectively registered).
The levels of plasma plasmalogen in retired female rats decrease by ovariectomy and intake of cholesterol-diet
Authors: Hashiguchi Kiwa , Kikuchi Takuma , Mizokami Takuya , Sato Masao , Nishimukai Megumi
Published: September 2022

Plasmalogens are functional glycerophospholipids that play important biological roles in the human body and are associated with various diseases. In our previous study, plasma choline plasmalogen level was reported to be strongly associated with factors of atherosclerosis and decreases with age. In this study, we created an animal model of low plasma plasmalogen and clarified the effect of aging on plasma plasmalogen metabolism and other plasma lipids in ovariectomized rats. Consequently, in the ovariectomized model using retired rats (Retire + OVX rats), we found a reduction in the ratio of plasmalogen in total phospholipids and an increase in cholesterol in plasma. Furthermore, this was more pronounced with the intake of a high-cholesterol diet in the Retire + OVX rats and is similar to the changes in plasmalogen and cholesterol levels in human atherosclerosis. In summary, this suggests that the ovariectomy model using retired rats is a useful model for low plasma plasmalogen levels.