bluuebunny/crossref_metadata_2025 huggingface dataset:
Silicon quantum dot (SQD)-catalyzed visible-light-induced ATRP and its application in controlled surface modification
Authors: Qiao Xiaoguang , Wang Qi , shi Ge , He Yanjie , Pang Xinchang
Published: October 2022

SiQD-catalyzed visible light induced ATRP provides not only good control of polymerization, but also has the potential for application in controlled surface modification through surface grafting photoATRP (SG-ATRP) with the assistance of MPS.
Photochemistry of pyruvic acid is governed by photo-induced intermolecular electron transfer through hydrogen bonds
Authors: Lewis Jennifer S. , Gaunt Adam P. , Comment Arnaud
Published: October 2022

When supercooled pyruvic acid is photo-irradiated, a radical detectable by ESR forms following the transfer of an electron from a molecule in its keto form to a molecule in its hydrated form. The latter subsequently degrades to CO2and acetic acid.
Concurrent Predictors of Supplementary Sign Use in School-Aged Children With Childhood Apraxia of Speech
Authors: Chenausky Karen V. , Verdes Alison , Shield Aaron
Published: October 2022

Purpose:

Manual sign is a common alternative mode of communication taught to children with childhood apraxia of speech (CAS). Gesture use is positively related to later increases in vocabulary and syntactic complexity in typical development, but there is little evidence supporting the use of manual sign for children with CAS. We sought to identify the communicative functions of signs and gestures produced by children with CAS and to identify concurrent factors suggesting which children are more likely to benefit from sign-supported speech intervention.

Method:

Measures of receptive and expressive language were gathered from 19 children (ages 3.8–11.1 years) with CAS in a school-based sign-supported speech program. Fourteen of the children produced a total of 145 manual signs, which included both gestures and signs from American Sign Language (M= 10.4 per child,SD= 11.6). Manual signs were coded according to whether they conveyed information that was semantically redundant with (complemented) or added information to (supplemented) their speech.

Results:

Children produced 107 complementary manual signs (75.4%) and 38 supplemental (24.6%) manual signs. Of the 38 supplemental signs, 24 (63.2%) provided additional information in the presence of unintelligible or no speech and 14 (36.8%) provided additional information in the presence of intelligible speech. Children's expressive language scores significantly predicted and accounted for 38.4% of the variance in the number of supplemental signs that children used.

Conclusion:

Children with CAS whose oral expressive language was relatively more impaired produced the most supplementary signs, suggesting that children with oral expressive language challenges are more likely to rely on them for communicating words they cannot yet speak.

Supplemental Material:

https://doi.org/10.23641/asha.21217814
Origin of eclipsing time variations in post-common-envelope binaries: Role of the centrifugal force
Authors: Navarrete Felipe H. , Schleicher Dominik R. G. , Käpylä Petri J. , Ortiz-Rodríguez Carolina A. , Banerjee Robi
Published: October 2022

Eclipsing time variations in post-common-envelope binaries were proposed to be due to the time-varying component of the stellar gravitational quadrupole moment. This is suggested to be produced by changes in the stellar structure due to an internal redistribution of angular momentum and the effect of the centrifugal force. We examined this hypothesis and present 3D simulations of compressible magnetohydrodynamics performed with the PENCIL CODE. We modeled the stellar dynamo for a solar-mass star with angular velocities of 20 and 30 times solar. We included and varied the strength of the centrifugal force and compared the results with reference simulations without the centrifugal force and with a simulation in which its effect is enhanced. The centrifugal force causes perturbations in the evolution of the numerical model, so that the outcome in the details becomes different as a result of nonlinear evolution. While the average density profile is unaffected by the centrifugal force, a relative change in the density difference between high latitudes and the equator of ∼10−4 is found. The power spectrum of the convective velocity is found to be more sensitive to the angular velocity than to the strength of the centrifugal force. The quadrupole moment of the stars includes a fluctuating and a time-independent component, which vary with the rotation rate. As very similar behavior is produced in absence of the centrifugal force, we conclude that it is not the main ingredient for producing the time-averaged and fluctuating quadrupole moment of the star. In a real physical system, we thus expect contributions from both components, that is, from the time-dependent gravitational force from the variation in the quadrupole term and from the spin-orbit coupling that is due to the persistent part of the quadrupole.
Novel Biomarkers of AKI in Cirrhosis
Authors: Juanola Adrià , Ma Ann T. , Pose Elisa , Ginès Pere
Published: October 2022

Acute kidney injury (AKI) is a frequent complication in patients with cirrhosis that is associated with poor outcomes and decreased survival. The definition of AKI in cirrhosis is currently based on changes of serum creatinine levels with respect to baseline values. Differential diagnosis of the causes of AKI is of major relevance, considering that some causes of AKI, such as hepatorenal syndrome, have specific treatment options and different prognosis. Prediction of kidney function recovery and patients' survival is also crucial in this patient population to guide clinical decisions. AKI biomarkers in cirrhosis have emerged as a promising tool for differential diagnosis and prognosis in this situation. There are consistent data showing that some urine biomarkers, particularly neutrophil gelatinase-associated lipocalin, may be useful in daily clinical practice for the differential diagnosis of the cause of AKI in cirrhosis. AKI biomarkers may constitute a useful tool for use in differential diagnosis, prognosis of renal function, and survival in patients with cirrhosis. This review focuses on the current state of knowledge and future perspective of novel biomarkers of AKI in cirrhosis.
Searching for the Genus Epidemicus in Chinese Patients: Findings from the Clificol COVID-19 Clinical Case Registry
Authors: Tournier Alexander , Fok Yvonne , van Haselen Robbert , To Aaron
Published: October 2022

Background The Clificol COVID-19 Support Project is an innovative international data collection project aimed at tackling some of the core questions in homeopathy. This paper reports on the further investigation of the genus epidemicus concept during the first wave of the pandemic in the Chinese population.

Methods The design is an observational clinical case registry study of Chinese patients with confirmed or suspected coronavirus disease 2019 (COVID-19). The symptoms were prospectively collected via a 150-item questionnaire. The concept of genus epidemicus, including the role of treatment individualization, was investigated by analyzing whether presenting symptoms clustered into distinct groups. Two standard statistical analysis techniques were utilized: principal component analysis for extracting the most meaningful symptoms of the dataset; the k-means clustering algorithm for automatically assigning groups based on similarity between presenting symptoms.

Results 20 Chinese practitioners collected 359 cases in the first half of 2020 (766 consultations, 363 prescriptions). The cluster analysis found two to be the optimum number of clusters. These two symptomatic clusters had a high overlap with the two most commonly prescribed remedies in these sub-populations: in cluster 1 there were 297 prescriptions, 95.6% of which were Gelsemium sempervirens; in cluster 2 there were 61 prescriptions, 95.1% of which were Bryonia alba.

Conclusion This is the first study to investigate the notion of genus epidemicus by using modern statistical techniques. These analyses identified at least two distinct symptom pictures. The notion of a single COVID-19 genus epidemicus did not apply in the studied population.
A artroplastia total de joelhos bilateral simultânea pode ser segura
Authors: Gali Julio Cesar , Brotto Anna Flavia de Crescenzo , de Mello Danilo Pássaro Pires , Mauad Juliana Ribeiro , Gali Filho Julio Cesar
Published: October 2022

Objetivos Os objetivos deste estudo foram analisar a segurança da artroplastia total bilateral de joelho simultânea (ATJBS) e investigar a satisfação dos pacientes com o procedimento realizado de forma concomitante.

Métodos Em um estudo prospectivo, avaliamos 45 pacientes submetidos à ATJBS feita por duas equipes cirúrgicas. A idade média dos pacientes foi 66,9 anos, sendo 33 do gênero feminino (73,3%) e 12 (26,6%) do gênero masculino. No período intra- e pós-operatório foi seguido um protocolo de medidas visando a segurança do procedimento. Avaliamos o tempo de cirurgia, a perda sanguínea pelo hematócrito (Ht) e hemoglobina (Hb), obtidos no primeiro dia de pós-operatório, a porcentagem de pacientes que receberam transfusão de concentrado de hemácias e quantidade de unidades que foram necessárias. Verificamos as complicações no período perioperatório e, ao final de três meses, inquirimos aos pacientes sobre a preferência entre o procedimento simultâneo ou estagiado.

Resultados O tempo médio de cirurgia foi de 169 minutos; no pós-operatório houve um decréscimo médio de 28,2% do Ht e de 27,0% da Hb. Ao todo, 16 pacientes (35,5%) receberam transfusão de concentrado de hemácias (média de 1,75 unidades por paciente que precisou de reposição). Tivemos 12 complicações menores (26,6%) e 2 complicações maiores (4,4%); além disso, nenhum paciente teve o diagnóstico clínico de trombose venosa profunda e não houve mortes.

Conclusões A ATJBS pode ser considerada um procedimento seguro, se realizada em pacientes selecionados e com um protocolo de cuidados para prevenir complicações. Esse procedimento teve a aprovação unânime dos pacientes.
Dual-comb ranging yields reliable surface acoustic wave amplitude measurements
Authors: Green Leigh Ann
Published: October 2022

Quantitative evaluation of mechanical movement at the picometer level found to be precise and accurate.
A generalized method for the Darboux transformation
Authors: Aktosun Tuncay , Unlu Mehmet
Published: October 2022

A method is presented to obtain the change in the potential and in the relevant wavefunction of a linear system of ordinary differential equations containing a spectral parameter, when that linear system is perturbed and a finite number of discrete eigenvalues are added to or removed from the spectrum. Some explicit formulas are derived for those changes by introducing certain fundamental linear integral equations for the corresponding unperturbed and perturbed linear systems. This generalized method is applicable in a unified manner on a wide class of linear systems. This is in contrast to the standard method for a Darboux transformation, which is specific to the particular linear system on which it applies. A comparison is provided in some special cases between this generalized method and the standard method for the Darboux transformation. In particular, when a bound state is added to the discrete spectrum, some Darboux transformation formulas are presented for the full-line Schrödinger equation, where those formulas resemble the Darboux transformation formulas for the half-line Schrödinger equation. The theory presented is illustrated with some explicit examples.
Experimental observation of the transition between hose and self-modulation instability regimes
Authors: Del Dotto A. , Berceanu A. C. , Biagioni A. , Ferrario M. , Fortugno G. , Pompili R. , Romeo S. , Rossi A. R. , Santangelo P. , Shpakov V. , Zigler A.
Published: October 2022

Plasma-based acceleration is one of the most promising technologies for the development of compact accelerators providing high-quality beams for research, medical, and industrial applications. The interaction with the plasma, however, can produce detrimental effects on the particle beam, such as the hose-instability, and ultimately limit its implementation. Several methods have been proposed to suppress such a process, for instance, by triggering and bringing to saturation the self-modulation instability. In the framework of plasma acceleration, we present, for the first time, the experimental observation of the transition from hose to self-modulation instability regimes. The measurements are obtained by using an ultra-relativistic electron beam interacting with the plasma confined in a capillary. The results provide a more comprehensive picture of the beam–plasma interaction and are validated with complete particle-in-cell simulations.
Internal rotation of ELM filaments on NSTX
Authors: Lampert M. , Diallo A. , Myra J. R. , Zweben S. J.
Published: October 2022

Edge localized modes (ELMs) are a threat to tokamaks due to their high heat and particle loads on plasma facing components. A significant portion of this energy is carried and deposited by the emerging ELM filaments, whose dynamics are directly connected to their impact. Therefore, understanding their underlying physics is important for the operation of future fusion reactors. Our paper extends our knowledge of ELM filaments by reporting on their internal rotation (spinning) around the magnetic field lines along which they are extended. Our analysis of gas-puff imaging data on National Spherical Torus Experiment shows that ELM filaments are characterized by internal rotation in the direction of the ion-gyromotion with ω=15.2 krad/s median angular velocity, which is approximately three times faster than the blob rotation in the background turbulence. The characteristic size of the ELM filament was also assessed and found to be similar to the blobs. A nearly linear trend was found between the angular velocity and the radial velocity of the ELM filament. The angular velocity was found to be linearly dependent on the distance of the filament from the separatrix, as well. An analytical model called the shear-induced rotation model was identified as a candidate for explaining the physics of the observations. Our results show that the modeled mechanism could significantly influence the rotation of the ELM filament; however, it cannot be a sole contributor.
Three-dimensional phase-field lattice-Boltzmann simulations of a rising bubble interacting with obstacles: Shape quantification and parameter dependence
Authors: Zhang Ang , Su Dongbo , Li Chuangming , Gao Yuyang , Dong Zhihua , Bai Shengwen , Jiang Bin , Pan Fusheng
Published: October 2022

Exploring the bubble dynamics in the presence of obstacles can improve understanding of mechanism, design, and operation of multiphase flow. However, large deformation and complex hydrodynamics during the bubble–obstacle interaction pose challenges for shape quantification and parameter dependence. In this work, the bubble–obstacle interaction is investigated by employing a conservative phase-field lattice-Boltzmann model implemented on a parallel platform. Two shape parameters, which are the combination of the bubble geometrical parameters, are defined to characterize the bubble deformation during rising, impacting, and sliding process. The effects of the flow parameters (Reynolds, Eötvös, and Morton numbers) and the obstacle geometry settings (size and layout) are discussed, and a multilinear correlation is established to obtain a thorough evaluation. The difference induced by spatial dimension is further discussed to illustrate the necessity of simulating three-dimensional liquid–gas flow. The results can help decode the intricate bubble dynamics and lay a foundation for developing physically informed models for predicting the bubble–obstacle interaction.
High-performance multiple-doped In2O3 transparent conductive oxide films in near-infrared light region
Authors: Chen Shuyi , Meng Fanying , Shi Jianhua , Yan Zhu , Liu Yiyang , Liu Zhengxin
Published: October 2022

High-quality W, Mo, Ti, Zr, and Ga-doped indium oxide (multiple-doped In2O3) films are deposited at room temperature by direct current magnetron sputtering process under different oxygen proportion, with 200 °C annealing. A maximum Hall mobility of 71.6 cm2 V−1 s−1 is obtained at a middle oxygen proportion of 2%, thanks to the reduction of impurity scattering center, which is nearly three times higher than an ITO film of 23.6 cm2 V−1 s−1. The multiple-doped In2O3 films showed a remarkable 30% improvement of the optical transmittance (>80%) in the near-infrared (NIR) region compared to the ITO film (about 60%), which is mainly attributed to the decrement of free carrier absorption due to low carrier concentration (<2 × 1020 cm−3), an order magnitude lower than the ITO film (1.56 × 1021 cm−3). Additionally, x-ray diffraction results confirm that the films have a polycrystalline structure with preferential orientation growth in the <100> direction. In the NIR region, the multiple-doped In2O3 films have a superior figure of merit of 5.02 × 10−3 Ω−1, which is an order magnitude higher than the ITO film (5.31 × 10−4 Ω−1). This work reports a new In2O3-based material with both high electrical and optical performance, which is suitable for the application of advanced optoelectronic devices.
Analytical models for phonon mean free path in polycrystalline nanostructures based on mean square displacement
Authors: Hori Takuma , Dames Chris
Published: October 2022

In this study, a numerical simulation method and analytical models for predicting the boundary scattering mean free path (MFP) of phonons in polycrystalline nanostructures are developed. The grain morphologies are assumed to be approximately equiaxed, i.e., forbidding needle-like or pancake-like morphologies. Adapting a technique from rarefied gas dynamics, the method evaluates the MFP from the mean square displacements of phonons that experience random motion and interface collisions in nanostructures. We confirm that the MFP in simple cubic polycrystalline nanostructures obtained by the simulations agrees with that reported in a previous study; this result supports the validity of the method. Two analytical models for high and low interfacial transmission probabilities at the crystal interfaces are also derived by considering the mean square displacements. We find that the grain-boundary intercept length distribution of polycrystalline structures is an essential parameter for determining this boundary scattering MFP. These analytical models reproduce the MFPs in simple cubic and Voronoi diagram polycrystalline nanostructures calculated by the numerical simulations. This result indicates that the boundary scattering MFP of phonons in polycrystalline nanostructures can be obtained once the intercept length distribution is evaluated, without any additional numerical simulations.
Unusually strong, tunable, and nonreciprocal light trapping and absorption in helically structured magnetoactive media
Authors: Gevorgyan A. H.
Published: October 2022

We investigated the absorption properties of photonic structures with both large optical activity and magneto-optical activity parameters. The photonic structure is a periodic helical 1D medium in an external magnetic field. The magneto-optical activity parameter g change effects on the absorption nonreciprocity spectra for both linear and circular polarizations and those for unpolarized (natural) light were investigated. We showed that in certain cases, the external magnetic field leads to a strong increase in light trapping, absorption, and absorption nonreciprocity. This system can operate as a powerful light source and asymmetric and tunable wide range high absorber as well. We also investigated the dependence of Q (total energy absorbed in a finite spectral range) and its density on the layer thickness for different values of magneto-optical activity parameter g. With a change in the parameter g, the value of Q changes over a wide range (increasing or decreasing over 40 or more times), i.e., we have a broadly tunable and nonreciprocal integral absorption, again, for both polarized and unpolarized light. We showed that there are values of the parameter of magneto-optical activity at which the integral absorption does not depend on the polarization of the incident light.
Airy coherent vortices: 3D multilayer self-accelerating structured light
Authors: Pan Jing , Wang Hao , Shen Yijie , Fu Xing , Liu Qiang
Published: October 2022

We propose and generate a class of structured light fulfilling the mathematical form of a SU(2) coherent state based on a set of circular Airy vortex modes. Such wave packets possess strong focus with both radial and angular self-accelerations, which exploit more general 3D inhomogeneous velocity control with global spatial symmetry of multilayer rotation akin to galactic kinematics, termed galaxy waves. Galaxy waves are endowed with higher degrees of freedom to control strong focusing and acceleration, which opens a direction of multi-dimensional accelerating of 3D structured light field, promising numerous applications in optical trapping, manufacturing, and nonlinear optics.
Dependence of the radiative lifetime on the type-II band offset in GaAsxSb1−x/GaAs quantum dots including effects of photoexcited carriers
Authors: Oteki Yusuke , Shoji Yasushi , Miyashita Naoya , Okada Yoshitaka
Published: October 2022

In quantum dot (QD) heterostructures that have a type-II band alignment, either the electron or the hole is confined inside the QD. Due to smaller electron–hole overlap in such structures, relatively long radiative lifetimes can be realized, which is beneficial for devices such as intermediate-band solar cells. The use of GaAsxSb1−x/GaAs QDs allows us to control the energy level of the confined state by changing the type-II conduction-band offset (CBO) without the need of changing the QD size. However, the dependence of the radiative lifetime τr on the CBO needs to be considered to achieve optimum device performance. In this work, GaAsxSb1−x/GaAs QDs were grown by molecular beam epitaxy. The amount of deposition was controlled to obtain QDs with approximately the same size even for different values of As composition x, and the carrier lifetime was determined by time-resolved photoluminescence measurements. Since the CBO becomes smaller for larger values of x, a simple model would predict a larger electron–hole overlap for larger x values, and thus, the lifetime should decrease monotonically. However, the experimentally obtained lifetime does not decrease monotonically, which has interesting implications for applications. We explain the observed trend by the effect of photoexcited carriers; a triangular potential well is formed around the QDs in the case of high excitation densities, and thus, electrons are localized near the QDs. We also calculated τr considering the effect of photoexcited carriers to confirm our model, and a similar tendency was obtained.
Radiation-induced conductivity in polystyrene at extremely low (79 K) temperature
Authors: Tyutnev Andrey , Saenko Vladimir , Mullakhmetov Ilshat , Abrameshin Andrey
Published: October 2022

Radiation-induced conductivity (RIC) of polystyrene has been studied experimentally and numerically in a broad time range from milliseconds to seconds at 79 K, which seems to have been done for the first time. It has been established that the hole dispersive transport is still operative but unlike the room temperature behavior it features an extremely small frequency factor (4 × 103 s−1) and accordingly low dispersion parameter (0.09). It has been shown that prompt conductivity per unit dose rate does not depend on temperature (290 or 79 K) and is equal to Kp=3.5×10−15Ω−1m−1Gy−1s (±20%) at 4 × 107 V/m. At 79 K, current–voltage characteristics of both prompt and delayed components are close enough and non-linear. Due to the contribution of the thermalized charge carriers, the RIC even at 79 K can be satisfactorily described by the semi-empirical Rose–Fowler–Vaisberg model based on the quasi-band multiple trapping mechanism just as it happens at room temperature.
Kirkwood–Buff integrals: From fluctuations in finite volumes to the thermodynamic limit
Authors: Simon J.-M. , Krüger P. , Schnell S. K. , Vlugt T. J. H. , Kjelstrup S. , Bedeaux D.
Published: October 2022

The Kirkwood–Buff theory is a cornerstone of the statistical mechanics of liquids and solutions. It relates volume integrals over the radial distribution function, so-called Kirkwood–Buff integrals (KBIs), to particle number fluctuations and thereby to various macroscopic thermodynamic quantities such as the isothermal compressibility and partial molar volumes. Recently, the field has seen a strong revival with breakthroughs in the numerical computation of KBIs and applications to complex systems such as bio-molecules. One of the main emergent results is the possibility to use the finite volume KBIs as a tool to access finite volume thermodynamic quantities. The purpose of this Perspective is to shed new light on the latest developments and discuss future avenues.
A network mechanics method to study the mechanism of the large-deformation fracture of elastomers
Authors: Lei Jincheng , Liu Zishun
Published: October 2022

This work presents a network mechanics method to reveal the fracture mechanism of the inhomogeneous polymer network of elastomers. The polymer network in elastomers is abstracted as a network model composed of cross-linkers, polymer chains, and volume elements. The hyperelastic deformation of the network model is characterized using the total energy composed by the free energy of all polymer chains and the volumetric deformation energy of all volume elements. The fracture behavior of the network model is described by the fracture criterion of polymer chains. By comparing the large-deformation fracture simulations of homogeneous and inhomogeneous network models, we find that the network inhomogeneity is one important fundamental cause of the ductile fracture and the low notch sensitivity of elastomers. We also find that the widely used Lake–Thomas model underestimates the intrinsic fracture energy of elastomers, because the intrinsic fracture energy of an elastomer network includes the elastic energy stored not only in the broken polymer chains, but also in the newly created dangling chains on a crack surface. Our simulations show that the intrinsic fracture energy of a four-armed elastomer network is about three times of that predicted by the Lake–Thomas model. This result agrees quite well with the previous experimental results.
Interfacial band parameters of ultrathin ALD–Al2O3, ALD–HfO2, and PEALD–AlN/ALD–Al2O3 on c-plane, Ga-face GaN through XPS measurements
Authors: Gong Jiarui , Zheng Zheyang , Vincent Daniel , Zhou Jie , Kim Jisoo , Kim Donghyeok , Ng Tien Khee , Ooi Boon S. , Chen Kevin J. , Ma Zhenqiang
Published: October 2022

Ultrathin oxides (UOs) and ultrathin nitrides (UNs) play a crucial role in forming lattice-mismatched semiconductor heterostructures that are fabricated by using semiconducting grafting approach. The grafting approach has shown its great potential to realize GaN-based heterojunction bipolar transistors by fulfilling the missing high-performance p-type nitrides with other p-type semiconductors. A handful of UO and UN dielectrics readily available by atomic layer deposition (ALD) satisfy the requirements of double-sided surface passivation and quantum tunneling for semiconductor grafting. Due to the states existing between the UO or UN conduction band and that of the GaN, the ALD deposited UO or UN layer can generate significant effects on the surface band-bending of GaN. Understanding the band parameters of the interface between UO or UN and c-plane Ga-face GaN can guide the selection of interfacial dielectrics for grafted GaN-based devices. In this study, we performed x-ray photoelectron spectroscopy measurements to obtain the band-bending properties on c-plane, Ga-face GaN samples coated by different ALD cycles of ultrathin-HfO2 or ultrathin AlN. The valence band spectra of GaN coated with ultrathin-ALD–Al2O3, ALD–HfO2, or PEALD–AlN/ALD–Al2O3 were further analyzed to calculate the valence and conduction band offsets between the ALD dielectrics and the Ga-face GaN under different thicknesses and post-deposition annealing conditions of the dielectrics.
Phonon physics in twisted two-dimensional materials
Authors: Ren Weijun , Chen Jie , Zhang Gang
Published: October 2022

As one of the most effective manipulation means to control the physical properties of two-dimensional van der Waals stacking materials, the twisted angle periodically regulates the interlayer interaction potential by generating moiré patterns. The decrease in Brillouin zone size and the change of high symmetry direction caused by the interlayer twisted angle lead to the emergence of the hybrid folded phonons—moiré phonons, which have noticeable impacts on phonon properties. This paper reviews the recent developments and discoveries on phonon properties in twisted two-dimensional stacking homogeneous and heterogeneous systems and focuses on the impacts of the interlayer twisted angle on phonon dispersion, such as interlayer coupling phonon modes and moiré phonons. Meanwhile, we introduced the recent research on the influence of the interlayer twisted angle on phonon transport behavior along the in-plane and out-of-plane directions. In addition, the theoretical and experimental open questions and challenges faced in the phonon characteristics of twisted two-dimensional materials are discussed, and some possible solutions are put forward.
Tailoring small-scale plasticity of nanotwined-copper micropillars via microstructures
Authors: Yan Shaohua , Zhong Zheng , Qin Qing. H.
Published: October 2022

Nanotwined (nt) copper is attractive in applications such as microbumps in the microelectronics industry because nt-copper presents sound mechanical and physical properties. To date, most studies of the mechanical properties of nt-copper have been performed at macroscales. However, different stories are told at micro/nanoscales, e.g., smaller size leads to higher strength. Understanding the mechanical properties of nt-copper at micro/nanoscales is crucial for improving the reliability and endurability of microdevices. In this paper, we fabricated nt-copper film with tailored microstructures, i.e., twin boundaries (TBs) with different spacings and orientations (parallel or slanted to loading direction). Then, we applied micro-compression testing, atomistic simulation, and theoretical analysis to investigate the influence of vertical twin-boundary spacing λ and orientation on the deformation behavior of nt-micropillars. Results show that the yield stress is increased with decreasing vertical λ. Micropillars with slanted λ = 15.5 nm TBs present the greatest strength, which may be attributed to a finer λ. The phenomenon, strength increasing with decreasing λ, was well explained by the Hall–Petch and confined layer slip models. Large-scale molecular dynamics simulations were used to uncover the atomistic and real-time deformation mechanisms. This microscale research on nt-micropillars may provide insights on designing advanced microelectronics.
Influence of quantum particles on self-gravitational magnetic dust acoustic double layers
Authors: Mirghassemzadeh Nasim , Dorranian Davoud , Saviz Shahrooz
Published: October 2022

The impact of Fermi–Dirac distributed electrons and ions on the features of dust acoustic double layers in a four-component magnetized dusty plasma was investigated. In this model, the plasma consists of Fermi–Dirac distributed electrons and ions and negative and positive dust particles. The plasma species experience electrical, magnetical, and self-gravitational forces as well as the degeneracy pressure force that is caused by the Pauli exclusion law and the quantum tunneling force due to Bohm force. Employing a reductive perturbation method, the quantum extended Korteweg-de Vries equation was extracted from the set of fluid equations. The results show that the energy of generated dust acoustic double layers is extremely smaller than that in similar classical plasmas. The ratio of the Fermi temperature of ions to electrons is an effective parameter in the structure of double layers. With the variation of this parameter, the structure of double layers changes from compressive to rarefactive, and its polarity switches from negative to positive.
Na2FeF4 as a stable cathode material for Na-ion batteries
Authors: Yan Qi , Xu Huan , Hoang Khang , Zhou Xiaolong , Kidkhunthod Pinit , Lightfoot Philip , Yao Wenjiao , Tang Yongbing
Published: October 2022

In the search of cathode materials for Na-ion batteries, iron-based compounds have attracted much attention due to the abundant resource, easy access, and environmental friendliness of iron. Herein, we report the synthesis, structure, and electrochemistry of a previously unknown compound in the Na–Fe–F system, formulated as Na2FeF4. It is prepared by an easy and mild hydrothermal reaction with oxalate as a Fe2+ protector. Based on the single crystal x-ray diffraction analysis, it crystallizes in space group Pmcb with a = 3.255 (3) Å, b = 5.591(7) Å, and c = 9.557(1) Å. The crystal structure features edge-sharing FeF6 octahedra to form [FeF4]∞ chains with Na+ ions located between chains. In electrochemical investigations, it is demonstrated that the material can deliver a reversible capacity of ∼90 mAh g−1 for 300 cycles in the window of 1.5–4.3 V with redox reactions at ∼3.0 V (vs Na+/Na). Such an activity originates from the Fe3+/Fe2+ redox couple, confirmed by x-ray absorption spectra and first-principles calculations.
The dynamics of a bubble in the internal fluid flow of a pipeline
Authors: Luo X. , Chen T. , Xiao W. , Yao X. L. , Liu J. L.
Published: October 2022

In the aeronautical and marine engineering fields, bubbles are often carried in the pipelines of filling systems and marine risers. Under the action of internal flow, air bubbles seriously threaten device security. Therefore, to analyze the motion and deformation of a bubble in the internal fluid flow of a pipeline, we establish a corresponding boundary element numerical model based on the potential flow theory. A comparison of the numerical model results with the experimental results verifies the accuracy of the model. Subsequently, we simulate the dynamics of a bubble under the action of the internal flow, and the influence of the velocity, pipe radius, and surface tension on the bubble movement are discussed. When the dimensionless flow velocity exceeds 0.3, the bubbles will be seriously deformed. Different flow velocity directions cause different deformations of the annular bubbles in the later stages. Additionally, the channel limits bubble deformation. If the pipe radius is greater than 5, the effect of the pipe on the bubble is negligible. We also find that surface tension keeps the bubbles morphologically stable under internal flow. When the surface tension coefficient exceeds 2.45 × 10−4, it will not make the bubble toroidal.
Pressure-sensitive ion conduction in a conical channel: Optimal pressure and geometry
Authors: Boon Willem Q. , Veenstra Tim E. , Dijkstra Marjolein , van Roij René
Published: October 2022

Using both analytic and numerical analyses of the Poisson–Nernst–Planck equations, we theoretically investigate the electric conductivity of a conical channel which, in accordance with recent experiments, exhibits a strong non-linear pressure dependence. This mechanosensitive diodic behavior stems from the pressure-sensitive build-up or depletion of salt in the pore. From our analytic results, we find that the optimal geometry for this diodic behavior strongly depends on the flow rate with the ideal ratio of tip-to-base-radii being equal to 0.22 at zero-flow. With increased flow, this optimal ratio becomes smaller and, simultaneously, the diodic performance becomes weaker. Consequently an optimal diode is obtained at zero-flow, which is realized by applying a pressure drop that is proportional to the applied potential and to the inverse square of the tip radius, thereby countering electro-osmotic flow. When the applied pressure deviates from this ideal pressure drop the diodic performance falls sharply, explaining the dramatic mechanosensitivity observed in experiments.
Oil and gas exploration and development in the Lake Eyre Basin: distribution and consequences for rivers and wetlands, including the Coongie Lakes Ramsar Site
Authors: Kingsford R. T. , Walburn A. J. D.
Published: October 2022

Context Altered flooding regimes and pollution threaten the world’s wetlands, including floodplains of the largely free-flowing rivers. Aims We investigated the distribution of current and future oil and gas production and exploration on the floodplains of the Lake Eyre Basin. Methods We compiled these data and their associated infrastructure across the basin floodplains, including the Coongie Lakes Ramsar Site. Key results There were 831 oil and gas wells across the Lake Eyre Basin, predominantly (98.6%) on Cooper Creek floodplains, with 296 wells in the Coongie Lakes Ramsar Site, with 281 well pads, roads (870 km) and 440 storages. Only eight referrals occurred under the Environment Protection and Biodiversity Conservation Act 1999, despite potential Ramsar wetland impacts. Future oil and gas production licences, primarily unconventional gas production, covered ∼2.91 × 106 ha (Cooper Creek), 0.63 × 106 ha (Diamantina) and 1.03 × 106 ha (Georgina) of the floodplains. Conclusions and implications Oil and gas production and exploration disrupt flooding regimes, with pollution (spills and greenhouse gas emissions). Little rigorous environmental assessment existed to protect the Lake Eyre Basin rivers and Coongie Lakes Ramsar Site, despite state and Commonwealth legislation and policy for protection, which remain largely ineffective in controlling oil and gas development on this free-flowing river.
Computationally guided conversion of the specificity of E-selectin to mimic that of Siglec-8
Authors: Wang Xiaocong , Hanes Melinda S. , Cummings Richard D. , Woods Robert J.
Published: October 2022

Sulfated glycans have been found to be associated with various diseases and therefore have significant potential in molecular pathology as biomarkers. Although lectins are useful reagents for detecting glycans, there is a paucity of sulfate-recognizing lectins, and those that exist, such as from
Maackia amurensis
, display mixed specificities. Recombinant lectin engineering offers an emerging tool for creating novel glycan recognition by altering and/or enhancing endogenous specificities. The present study demonstrated the use of computational approaches in the engineering of a mutated form of E-selectin that displayed highly specific recognition of 6′-sulfo-sialyl Lewis X (6′-sulfo-sLe
x
), with negligible binding to its endogenous nonsulfated ligand, sLe
x
. This new specificity mimics that of the unrelated protein Siglec-8, for which 6′-sulfo-sLe
x
is its preferred ligand. Molecular dynamics simulations and energy calculations predicted that two point mutations (E92A/E107A) would be required to stabilize binding to the sulfated oligosaccharide with E-selectin. In addition to eliminating putative repulsions between the negatively charged side chains and the sulfate moiety, the mutations also abolished favorable interactions with the endogenous ligand. Glycan microarray screening of the recombinantly expressed proteins confirmed the predicted specificity change but also identified the introduction of unexpected affinity for the unfucosylated form of 6′-sulfo-sLe
x
(6′-sulfo-sLacNAc). Three key requirements were demonstrated in this case for engineering specificity for sulfated oligosaccharide: 1) removal of unfavorable interactions with the 6′-sulfate, 2) introduction of favorable interactions for the sulfate, and 3) removal of favorable interactions with the endogenous ligand.
A balance between vector survival and virus transmission is achieved through JAK/STAT signaling inhibition by a plant virus
Authors: Wang Yu-Meng , He Ya-Zhou , Ye Xin-Tong , Guo Tao , Pan Li-Long , Liu Shu-Sheng , Ng James C. K. , Wang Xiao-Wei
Published: October 2022

Viruses pose a great threat to animal and plant health worldwide, with many being dependent on insect vectors for transmission between hosts. While the virus–host arms race has been well established, how viruses and insect vectors adapt to each other remains poorly understood. Begomoviruses comprise the largest genus of plant-infecting DNA viruses and are exclusively transmitted by the whitefly
Bemisia tabaci
. Here, we show that the vector Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway plays an important role in mediating the adaptation between the begomovirus tomato yellow leaf curl virus (TYLCV) and whiteflies. We found that the JAK/STAT pathway in
B. tabaci
functions as an antiviral mechanism against TYLCV infection in whiteflies as evidenced by the increase in viral DNA and coat protein (CP) levels after inhibiting JAK/STAT signaling. Two STAT-activated effector genes,
BtCD109-2
and
BtCD109-3
, mediate this anti-TYLCV activity. To counteract this vector immunity, TYLCV has evolved strategies that impair the whitefly JAK/STAT pathway. Infection of TYLCV is associated with a reduction of JAK/STAT pathway activity in whiteflies. Moreover, TYLCV CP binds to STAT and blocks its nuclear translocation, thus, abrogating the STAT-dependent transactivation of target genes. We further show that inhibition of the whitefly JAK/STAT pathway facilitates TYLCV transmission but reduces whitefly survival and fecundity, indicating that this JAK/STAT-dependent TYLCV–whitefly interaction plays an important role in keeping a balance between whitefly fitness and TYLCV transmission. This study reveals a mechanism of plant virus–insect vector coadaptation in relation to vector survival and virus transmission.
Early death in a mouse model of Alzheimer’s disease exacerbated by microglial loss of TAM receptor signaling
Authors: Huang Youtong , Lemke Greg
Published: October 2022

Recurrent seizure is a common comorbidity in early-stage Alzheimer’s disease (AD) and may contribute to AD pathogenesis and cognitive decline. Similarly, many mouse models of Alzheimer’s disease that overproduce amyloid beta are prone to epileptiform seizures that may result in early sudden death. We studied one such model, designated
APP/PS1
, and found that mutation of the TAM receptor tyrosine kinase (RTK) Mer or its ligand Gas6 greatly exacerbated early death. Lethality was tied to violent seizures that appeared to initiate in the dentate gyrus (DG) of the hippocampus, where Mer plays an essential role in the microglial phagocytosis of both apoptotic and newborn cells normally generated during adult neurogenesis. We found that newborn DG neurons and excitatory synapses between the DG and the cornu ammonis field 3 (CA3) field of the hippocampus were increased in TAM-deficient mice, and that premature death and adult neurogenesis in these mice were coincident. In contrast, the incidence of lethal seizures and the deposition of dense-core amyloid plaques were strongly anticorrelated. Together, these results argue that TAM-mediated phagocytosis sculpts synaptic connectivity in the hippocampus, and that seizure-inducing amyloid beta polymers are present prior to the formation of dense-core plaques.
Escape from breast tumor dormancy: The convergence of obesity and menopause
Authors: Roy Roopali , Yang Jiang , Shimura Takaya , Merritt Lauren , Alluin Justine , Man Emily , Daisy Cassandra , Aldakhlallah Rama , Dillon Deborah , Pories Susan , Chodosh Lewis A. , Moses Marsha A.
Published: October 2022

Obesity is associated with an increased risk of, and a poor prognosis for, postmenopausal (PM) breast cancer (BC). Our goal was to determine whether diet-induced obesity (DIO) promotes 1) shorter tumor latency, 2) an escape from tumor dormancy, and 3) an acceleration of tumor growth and to elucidate the underlying mechanism(s). We have developed in vitro assays and PM breast tumor models complemented by a noninvasive imaging system to detect vascular invasion of dormant tumors and have used them to determine whether obesity promotes the escape from breast tumor dormancy and tumor growth by facilitating the switch to the vascular phenotype (SVP) in PM BC. Obese mice had significantly higher tumor frequency, higher tumor volume, and lower overall survival compared with lean mice. We demonstrate that DIO exacerbates mammary gland hyperplasia and neoplasia, reduces tumor latency, and increases tumor frequency via an earlier acquisition of the SVP. DIO establishes a local and systemic proangiogenic and inflammatory environment via the up-regulation of lipocalin-2 (LCN2), vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) that may promote the escape from tumor dormancy and tumor progression. In addition, we show that targeting neovascularization via a multitargeted receptor tyrosine kinase inhibitor, sunitinib, can delay the acquisition of the SVP, thereby prolonging tumor latency, reducing tumor frequency, and increasing tumor-free survival, suggesting that targeting neovascularization may be a potential therapeutic strategy in obesity-associated PM BC progression. This study establishes the link between obesity and PM BC and, for the first time to our knowledge, bridges the dysfunctional neovascularization of obesity with the earliest stages of tumor development.
Flux coupling, not specificity, shapes the transport and phylogeny of SLC6 glycine transporters
Authors: Le Guellec Bastien , Rousseau France , Bied Marion , Supplisson Stéphane
Published: October 2022

ATB

0
,
+

(
SLC6A14
) is a member of the amino acid transporter branch of the SLC6 family along with GlyT1 (
SLC6A9
) and GlyT2 (
SLC6A5
), two glycine-specific transporters coupled to 2:1 and 3:1 Na

+

:Cl

−

, respectively. In contrast, ATB

0
,
+

exhibits broad substrate specificity for all neutral and cationic amino acids, and its ionic coupling remains unsettled. Using the reversal potential slope method, we demonstrate a 3:1:1 Na

+

:Cl

−

:Gly stoichiometry for ATB

0
,
+

that is consistent with its 2.1
e
/Gly charge coupling. Like GlyT2, ATB

0
,
+

behaves as a unidirectional transporter with virtually no glycine efflux at negative potentials after uptake, except by heteroexchange as remarkably shown by leucine activation of NMDARs in
Xenopus
oocytes coexpressing both membrane proteins. Analysis and computational modeling of the charge movement of ATB

0
,
+

reveal a higher affinity for sodium in the absence of substrate than GlyT2 and a gating mechanism that locks Na

+

into the apo-transporter at depolarized potentials. A 3:1 Na

+

:Cl

−

stoichiometry justifies the concentrative transport properties of ATB

0
,
+

and explains its trophic role in tumor growth, while rationalizing its phylogenetic proximity to GlyT2 despite their extreme divergence in specificity.