Sulfur vacancies and heterogeneous interfaces promote high performance sodium storage of bimetallic chalcogenide hollow nanospheres

Transition metal sulfides have high theoretical capacities and are considered as potential anode materials for sodium-ion batteries.However,due to low inherent conductivity and significant volume expansion,the electrochemical performance is greatly limited.In this study,a nickel/manganese sulfide material(Ni_(0.96)S_(x)/MnS_(y)-NC)with adjustable sulfur vacancies and heterogeneous hollow spheres was prepared using a simple method.The introduction of a concentration-adjustable sulfur vacancy enables the generation of a heterogeneous interface between bimetallic sulfide and sulfur vacancies.This interface collectively creates an internal electric field,improving the mobility of electrons and ions,increasing the number of electrochemically active sites,and further optimizing the performance of Na~+storage.The direction of electron flow is confirmed by Density functional theory(DFT)calculations.The hollow nano-spherical material provides a buffer for expansion,facilitating rapid transfer kinetics.Our innovative discovery involves the interaction between the ether-based electrolyte and copper foil,leading to the formation of Cu_9S_5,which grafts the active material and copper current collector,reinforcing mechanical supporting.This results in a new heterostructure of Cu_9S_5 with Ni_(0.96)S_(x)/MnS_(y),contributing to the stabilization of structural integrity for long-cycle performance.Therefore,Ni_(0.96)S_(x)/MnS_(y)-NC exhibits excellent electrochemical properties following our modification route.Regarding stability performance,Ni0_(.96)S_(x)/MnS_(y)-NC demonstrates an average decay rate of 0.00944%after 10,000 cycles at an extremely high current density of 10000 mA g^(-1),A full cell with a high capacity of 304.2 mA h g^(-1)was also successfully assembled by using Na_(3)V_(2)(PO_(4))_(3)/C as the cathode.This study explores a novel strategy for interface/vacancy co-modification in the fabrication of high-performance sodium-ion batteries electrode.

Cognitive Navigation for Intelligent Mobile Robots:A Learning-Based Approach With Topological Memory Configuration

Autonomous navigation for intelligent mobile robots has gained significant attention,with a focus on enabling robots to generate reliable policies based on maintenance of spatial memory.In this paper,we propose a learning-based visual navigation pipeline that uses topological maps as memory configurations.We introduce a unique online topology construction approach that fuses odometry pose estimation and perceptual similarity estimation.This tackles the issues of topological node redundancy and incorrect edge connections,which stem from the distribution gap between the spatial and perceptual domains.Furthermore,we propose a differentiable graph extraction structure,the topology multi-factor transformer(TMFT).This structure utilizes graph neural networks to integrate global memory and incorporates a multi-factor attention mechanism to underscore elements closely related to relevant target cues for policy generation.Results from photorealistic simulations on image-goal navigation tasks highlight the superior navigation performance of our proposed pipeline compared to existing memory structures.Comprehensive validation through behavior visualization,interpretability tests,and real-world deployment further underscore the adapt-ability and efficacy of our method.

GLP-1 receptor agonists and myocardial metabolism in atrial fibrillation

Atrial fibrillation(AF)is the most common cardiac arrhythmia.Many medical conditions,including hypertension,diabetes,obesity,sleep apnea,and heart failure(HF),increase the risk for AF.Cardiomyocytes have unique metabolic characteristics to maintain adenosine triphosphate production.Significant changes occur in myocardial metabolism in AF.Glucagon-like peptide-1 receptor agonists(GLP-1RAs)have been used to control blood glucose fluctuations and weight in the treatment of type 2 diabetes mellitus(T2DM)and obesity.GLP-1RAs have also been shown to reduce oxidative stress,inflammation,autonomic nervous system modulation,and mitochondrial function.This article reviews the changes in metabolic characteristics in cardiomyocytes in AF.Although the clinical trial outcomes are unsatisfactory,the findings demonstrate that GLP-1 RAs can improve myocardial metabolism in the presence of various risk factors,lowering the incidence of AF.

Non-parallel double-crack propagation in rock-like materials under uniaxial compression

Coalescence among fractures would have influence on the stability of rock masses. Deep understanding of mechanical behavior of fractured rock masses is an important mean to identify failure mechanism of geological disaster. In this study, crack propagation processing was studied through loading pre-fractured specimens of concrete block, termed as rock-like material, in uniaxial compression tests. New non-parallel double-crack geometry was introduced to observe crack coalescence. The flaw combinations are different from the normally used flaw configurations. In addition, ultrasonic detection tests were performed on the test blocks. The stress and strain data of these tests and characteristic parameters of sound wave were recorded. The stress-strain curves of each test block under the uniaxial compression test were drawn, relations among deformation characteristics and crack angle of the crack specimens, and their overall strength were analyzed. It is found that strength of the specimen decreases as crack inclination increases under two crack inclinations. The highest uniaxial compressive strength is found in the specimen with the cracks at the same angle in different directions. Based on description of the crack initiation location, crack surface and the ultimate failure patterns, failure modes of eight subtype for test blocks are divided into three categories. It is expected that the study results could be beneficial for engineering application of jointed rock masses.

MXenes for Solar Cells

Application of two-dimensional MXene materials in photovoltaics has attracted increasing attention since the first report in 2018 due to their metallic electrical conductivity,high carrier mobility,excellent transparency,tunable work function and superior mechanical property.In this review,all developments and applications of the Ti3C2Tx MXene(here,it is noteworthy that there are still no reports on other MXenes’application in photovoltaics by far)as additive,electrode and hole/electron transport layer in solar cells are detailedly summarized,and meanwhile,the problems existing in the related studies are also discussed.In view of these problems,some suggestions are given for pushing exploration of the MXenes’application in solar cells.It is believed that this review can provide a comprehensive and deep understanding into the research status and,moreover,helps widen a new situation for the study of MXenes in photovoltaics.

Self-Catalyzed Rechargeable Lithium-Air Battery by in situ Metal Ion Doping of Discharge Products: A Combined Theoretical and Experimental Study

Lithium-air battery has emerged as a viable electrochemical energy technology;yet a substantial overpotential is typically observed,due to the insulating nature of the discharge product Li_(2)O_(2) that hinders the reaction kinetics and device performance.Furthermore,finite solid–solid/-liquid interfaces are formed between Li_(2)O_(2) and catalysts and limit the activity of the electrocatalysts in battery reactions,leading to inadequate electrolytic efficiency.Herein,in-situ doping of Li_(2)O_(2) by select metal ions is found to significantly enhance the lithium-air battery performance,and Co^(2+)stands out as the most effective dopant among the series.This is ascribed to the unique catalytic activity of the resulting Co-O_(x) sites towards oxygen electrocatalysis,rendering the lithium-air battery self-catalytically active.Theoretical studies based on density functional theory calculations show that structural compression occurs upon Co^(2+)doping,which lowers the energy barrier of Li_(2)O_(2) decomposition.Results from this study highlight the significance of in situ electrochemical doping of the discharge product in enhancing the performance of lithium-air battery.

Protective effects of catalpol on cardio-cerebrovascular diseases: A comprehensive review

Catalpol,an iridoid glucoside isolated from Rehmannia glutinosa,has gained attention due to its potential use in treating cardio-cerebrovascular diseases(CVDs).This extensive review delves into recent studies on catalpol's protective properties in relation to various CVDs,such as atherosclerosis,myocardial ischemia,infarction,cardiac hypertrophy,and heart failure.The review also explores the compound's anti-oxidant,anti-inflammatory,and anti-apoptotic characteristics,emphasizing the role of vital signaling pathways,including PGC-1a/TERT,PI3K/Akt,AMPK,Nrf2/HO-1,estrogen receptor(ER),Nox4/NF-kB,and GRP78/PERK.The article discusses emerging findings on catalpol's ability to alleviate diabetic cardiovascular complications,thrombosis,and other cardiovascular-related conditions.Although clinical studies specifically addressing catalpol's impact on CVDs are scarce,the compound's established safety and well-tolerated nature suggest that it could be a valuable treatment alternative for CVD patients.Further investigation into catalpol and related iridoid derivatives may unveil new opportunities for devising natural and efficacious CVD therapies.

The Analysis of an SIRS Epidemic Model with Discrete Delay on Scale-Free Network

A new epidemic SIRS model with discrete delay on scale-free network is presented. We give the formula of the basic reproductive number for the model and prove that the disease dies out when the basic reproductive number is less than unity, while the disease is uniformly persistent when the basic reproductive number is more than unity. Numerical simulations are given to demonstrate the main results.

Hollow sphere of heterojunction(NiCu)S/NC as advanced anode for sodium-ion battery

Metal sulfide is considered as a potential anode for sodium-ion batteries(SIBs),due to the high theoretical capacity,strong thermodynamic stability and low-cost.However,their cycle capacity and rate performance are limited by the excessive expansion rate and low intrinsic conductivity.Herein,heterogeneous hollow sphere NiS-Cu_(9)S_(5)/NC(labeled as(NiCu)S/NC)based on Oswald ripening mechanism was prepared through a simple and feasible methodology.From a structural perspective,the hollow structure provides an expansion buffer and raises the electrochemical active area.In terms of electron/ion during the cycles,Na^(+)storage mechanism is optimized by NiS/Cu_(9)S_(5)heterogeneous interface,which increases the storage sites and shortens the migration path of Na^(+).The formation of built-in electric field strengthens the electron/ion mobility.Based on the first principle calculations,it is further proved the formation of heterogeneous interfaces and the direction of electron flow.As the anode for SIBs,the synthesized(NiCu)S/NC delivers high reverse capacity(559.2 mA h g^(-1)at 0.5 A g^(-1)),outstanding rate performance(185.3 mA h g^(-1)at 15 A g^(-1)),long-durable stability(342.6 mA h g^(-1)at 4 A g^(-1)after 1500cycles,150.0 m A h g^(-1)at 10 A g^(-1)after 20,000 cycles with 0.0025%average attenuation rate).The matching cathode electrode Na_(3)V_(2)(PO_(4))_(3)/C is assembled with(NiCu)S/NC for the full-battery that achieves high energy density(253.7 W h kg^(-1))and reverse capacity(288.7 mA h g^(-1)).The present work provides a distinctive strategy for constructing electrodes with excellent capacity and stability for SIBs.

A Giant Right Atrial Myxoma with Blood Supply from the Left and Right Coronary Arteries:Once in a Blue Moon

Cardiac myxomas,the commonest primary benign cardiac tumors,are extremely rare,with an incidence ranging from 0.0017 to 0.19%and only about one-fi fth of them originating from the right chambers of the heart.A 60-year-old woman was admitted because of recurrent attacks of chest tightness and shortness of breath.Transthoracic echocardiography detected a giant mass in the right atrium;myxoma was indicated by[18 F]fl uorodeoxyglucose PET/CT.Preoperative selective coronary angiography was performed to assess the extent and severity of coronary stenosis,and showed a strongly neovascularized right atrial mass supplied by two feeding vessels with multiple branches from the left and right coronary arteries.The myxoma was successfully excised with open heart surgery and the patient was free of myxoma recurrence during the 3-year follow-up.

Similarities and Differences of CT Features between COVID-19 Pneumonia and Heart Failure

Aims:During the COVID-19 epidemic,chest computed tomography(CT)has been highly recommended for screen-ing of patients with suspected COVID-19 because of an unclear contact history,overlapping clinical features,and an overwhelmed health system.However,there has not been a full comparison of CT for diagnosis of heart failure or COVID-19 pneumonia.Methods:Patients with heart failure(n=23)or COVID-19 pneumonia(n=23)and one patient with both diseases were retrospectively enrolled.Clinical information and chest CT images were obtained and analyzed.Results:There was no difference in ground-glass opacity,consolidation,crazy paving pattern,the lobes affected,and septal thickening between heart failure and COVID-19 pneumonia.However,a less rounded morphology(4%vs.70%,P=0.00092),more peribronchovascular thickening(70%vs.35%,P=0.018)and fi ssural thickening(43%vs.4%,P=0.002),and less peripheral distribution(30%vs.87%,P=0.00085)were found in the heart failure group than in the COVID-19 group.Importantly,there were also more patients with upper pulmonary vein enlargement(61%vs.4%,P=0.00087),subpleural effusion(50%vs.0%,P=0.00058),and cardiac enlargement(61%vs.4%,P=0.00075)in the heart failure group than in the COVID-19 group.Besides,more fi brous lesions were found in the COVID-19 group,although there was no statistical difference(22%vs.4%,P=0.080).Conclusions:Although there is some overlap of CT features between heart failure and COVID-19,CT is still a useful tool for differentiating COVID-19 pneumonia.

Periodic Solutions of Cohen-Grossberg-Type BAM Neural Networks with Time-Varying Delays

Sufficient conditions to guarantee the existence and global exponential stability of periodic solutions of a Cohen-Grossberg-type BAM neural network are established by suitable mathematical transformation.

Female urinary incontinence in China after 15 years’efforts:Resultsfrom large-scale nationwide surveys

Urinary incontinence(UI)is a disease that quietly yet seriously impacts women's health and represents a global health burden that is often neglected.This study aims to systematically assess the prevalence and dynamics of female UI in China,and can inform further policies and have international implications.This study used three nationwide investigations:A national cross-sectional survey in 2021;another nationwide cross-sectional survey in 2006;and data regarding the institutions and physicians providing pelvic floor rehabilitation services from 2005 to 2019.The weighted prevalence of female UI and its subtypes,including stress UI(SUI),urgency UI(UUI),and mixed UI(MUI),were estimated as primary outcomes.Knowledge,attitude and care-seeking behaviors of UI were evaluated.It was found that the weighted prevalence of female UI was 16.0%(95%CI,13.3%–19.1%)with SUI remaining the predominant subtype(7.0%)in 2021,followed by MUI(6.5%)and UUI(1.9%).The estimated absolute number of Chinese adult women with UI was 85.8 million in 2021.52.7%(95%CI,45.9%–59.4%)of women were aware that UI was a medical condition,and only 10.1%of women with UI sought health care.After 15 years of development,there were 8400 pelvic floor rehabilitation institutions and nearly 10,000 relevant physicians in ChinaDthey were found to be associated with UI prevalence.The UI prevalence in China was significantly lower in 2021 compared to that in 2006.Despite the achievement,UI remains a public health problem,especially given China's fast aging and three-child policy.More innovations,especially those that can facilitate care seeking,are needed to address this prevalent yet treatable condition.

Learning from Neighbors and Differentiating Export Quality

This paper explores how learning from neighboring firms affects new exporters' product quality. It builds a Bayesian learning model to study how new exporters revise their prior beliefs about foreign customers' preferences for product quality from neighboring pioneering exporters. The model shows that a new exporter improves its product quality when it receives a positive quality-preference signal from its neighbors. The learning process of a firm depends on the number of neighbors, the level and heterogeneity of their export quality, and its own prior knowledge of the market. Highly disaggregated firm–product–country level transaction data provide robust evidence for this. The results also suggest that the impact of neighboring signals on a new exporter's quality can be channeled through the importation of high-quality intermediate inputs and more fixed investment. Learning effects are heterogeneous across firms and learning can influence other aspects of export performance.

滇中高原亚热带半湿润常绿阔叶林植物群落多样性特征

森林动态监测样地是研究群落构建和物种多样性维持机制的重要平台。半湿润常绿阔叶林是滇中高原的地带性植被类型。但由于人类活动的长期影响,半湿润常绿阔叶林天然群落当前仅呈片断化状态,零星分布于偏远山地。参照美国史密森热带研究院热带森林研究中心的样地建设标准,我们分别在云南省曲靖珠江源(ZJY)、楚雄雕翎山(DLS)和大理鸡足山(JZS)建立了面积为10 ha (500 m×200 m)、8.24 ha (1个260 m×240 m的小样地和2个100 m×100 m的小样地)和20.16 ha (720 m×280 m)的3个森林动态监测样地。本文以这3个样地的植物群落为研究对象,运用背包式激光雷达、激光测距仪等获取相关基础数据,并对各样地的植物群落进行物种鉴定、区系分析、群落分类及群落结构分析。结果表明:(1) 3个样地共发现维管植物619种,隶属于120科355属,其中珠江源样地70科120属157种,雕翎山样地92科224属319种,鸡足山样地100科255属353种;(2)DBH≥1 cm的木本植物存活个体共有103,951株,其中珠江源样地24,932株、雕翎山样地25,222株、鸡足山样地53,797株,活个体密度分别为2,493.2株/ha、3,060.9株/ha、2,689.9株/ha;(3)样地群内所有维管植物在属和种水平上的温带区系成分合计占比分别为51.3%和24.7%,中国特有种的比例为33.0%;(4)样地群内的植物群落可分为8个群系,分别为元江栲(Castanopsis orthacantha)群系、高山栲(C.delavayi)群系、白穗石栎(Lithocarpus craibianus)群系、滇石栎(L.dealbatus)群系、云南松(Pinus yunnanensis)群系、黄毛青冈(Cyclobalanopsis delavayi)群系、光叶石栎(L.mairei)群系和灰背栎(Quercus senescens)群系;雕翎山样地群系类型最多、珠江源样地最少;(5)鸡足山样地和雕翎山样地乔木树种的径级结构呈倒“J”型,珠江源样地呈单峰型;鸡足山样地在80–100年以前经历过一次局部性的严重干扰,雕翎山样地在50–80年前后经历过一次普遍性的轻中度干扰迹象,珠江源样地在37年前曾经历过一次覆盖性的火干扰,样地间森林群系类型和径级结构的差异主要取决于群落演替程度和地形差异。

云南鸡足山半湿润常绿阔叶林群落木本植物多样性格局与环境解释

生物多样性格局是生物群落构建过程的反映,有助于理解生态系统的物种共存机制。半湿润常绿阔叶林是亚热带西部半湿润气候下的地带性植被类型,对其群落内物种多样性的空间异质格局及影响因子的认识还比较缺乏,基于大样地的研究还未见报道。本文基于鸡足山20.16 ha森林动态监测样地504个样方的木本植物调查数据和TWINSPAN群落分类结果,分析了样方尺度上α多样性和β多样性的空间分布格局及其环境影响因子。结果表明:(1)样地内云南松(Pinus yunnanensis)群落及其乔木和灌木的物种丰富度均高于高山栲(Castanopsisdelavayi)群落和元江栲(C.orthacantha)群落;高山栲群落及其灌木物种丰富度低于元江栲群落,乔木物种丰富度则高于元江栲群落。相反,元江栲群落的Shannon-Wiener多样性指数最高,其次为高山栲群落,云南松群落的最低。基于净种间亲缘关系指数,元江栲群落、高山栲群落、云南松群落的谱系结构分别为聚集、随机、发散。(2)对物种丰富度存在普遍性影响的因子有土壤总氮、pH值、相对海拔高度、木本植物的胸高断面积之和;导致乔木种丰富度变化的主要因子有土壤总氮、pH值、胸高断面积之和;导致灌木种丰富度变化的主要因子是相对海拔高度、土壤总氮、坡度和地形湿度指数。(3)物种β多样性格局显示,随着空间距离和环境距离的增大,物种差异性和物种周转率增大,即环境越相似,群落越相似。上述结果表明,鸡足山样地中先锋性的云南松群落与稳定的元江栲群落和高山栲群落在物种多样性和构成上存在显著差异,指示了半湿润常绿阔叶林异质斑块所对应的物种共存和物种多样性维持特征,为进一步的机理性研究提供了有效证据。

云南鸡足山半湿润常绿阔叶林的林隙干扰格局与成因

林隙(forest gap,FG)是森林干扰中的一种常见形式。作为森林景观流动镶嵌结构的基础,林隙对森林群落更新和物种共存具有重要作用。本文基于2022年对云南大理鸡足山半湿润常绿阔叶林动态监测样地的植物群落调查结果,统计了所有活立木和粗木质残体(coarsewoodydebris,CWD)的物种组成和径级结构,分析了样地内所有木本植物胸高断面积和林隙形成木(forestgapmaker,FGM)数量的空间格局,并利用广义线性回归模型结合方差分解对林隙形成木定义的林隙干扰强度进行了定量环境解析。结果表明:(1)样地内粗木质残体的数量和胸高断面积之和分别相当于全部活立木的13.6%和15.8%;全部粗木质残体属于57种木本植物,共计12,317株;形成林隙形成木的有12个物种,共计2,280株。(2)活立木和粗木质残体的径级结构均呈倒“J”形,即小径级数量多、大径级数量少,反映了样地群落中的树木死亡主要源自群落演替前期的自疏过程。(3)林隙形成木的数量和平均密度按折干木、枯倒木、枯立木、活倒木依次减少。活立木、粗木质残体和林隙形成木的胸高断面积之和在样地内的分布差异显著:沟谷两侧的山坡较高,底部较低;各类林隙形成木均在浅沟沟谷侧坡数量最多,沟谷最少,除活倒木外其余3类在深沟沟谷及侧坡上均有分布。(4)环境因子对枯立木、枯倒木、折干木、活倒木的数量的解释率依次为16.7%、25.6%、37.2%和76.0%;生物竞争和自疏过程主导了枯立木和枯倒木的形成,对活倒木数量贡献最大的因子是土壤养分,而折干木的形成则由地形因子和生物因子共同驱动。

Ductile and ultrahigh-strength eutectic high-entropy alloys by large-volume 3D printing

1.Introduction Additive manufacturing or 3D printing outweighs conventional casting methods in the aspect of complex parts fabrication,which can realize one-step formation without the need of complicated cast dies.3D printing significantly promotes industrial production for making near-net shaped components.However,this promising technique is not always ideally applicable for metals and alloys.For example,titanium alloys prepared by 3D printing often suf-fer from poor plasticity,and usually require further complex heat treatment or hot isostatic pressing treatment,in order to remove internal stress and regulate plasticity and strength[1,2],which de-feats the original intention of employing additive manufacturing.One of the fundamental causes for such issues is the low fluidity of the alloys upon melting,leading to great chemical heterogeneity,high porosity content and residual stresses.This limitation hinders further design and fabrication of high-performance printable alloys from large scale production and application.

柔性抗结冰表面的制备及其性能

冰的附着和累积是常见自然现象,但给人类社会带来诸多不便甚至发生重大事故。抗结冰表面是当前研究的热点课题之一,其表面特性是影响结冰最为关键的因素。但是结冰条件的复杂性及结冰类型的多样性致使抗结冰材料的研究面临很大挑战,存在的稳定性差、应用条件局限性等诸多问题尚未解决,不能满足实际应用的需求。本文根据表面分子的柔性或滑移性对抗结冰性能的影响,提出了柔性抗结冰表面的概念,总结了柔性抗结冰表面的种类(本征柔性表面、缓释柔性表面、润滑柔性表面)及其抗结冰机理和近年来取得的一些重要研究成果,并对柔性抗结冰表面存在的问题进行了分析,以期为抗结冰材料的研究提供新的研究思路和方法。

Rapid preparation of carbon-supported ruthenium nanoparticles by magnetic induction heating for efficient hydrogen evolution reaction in both acidic and alkalinemedia

Ruthenium has been hailed as a competitive alternative for platinum toward hydrogen evolution reaction(HER),a critical process in electrochemical water splitting.In this study,we successfully prepare metallic Ru nanoparticles supported on carbon paper by utilizing a novel magnetic induction heating(MIH)method.The samples are obtained within seconds,featuring a Cl-enriched surface that is unattainable via conventional thermal annealing.The best sample within the series shows a remarkable HER activity in both acidic and alkaline media with an overpotential of only-23 and-12 mV to reach the current density of 10 mA/cm^(2),highly comparable to that of the Pt/C benchmark.Theoretical studies based on density functional theory show that the excellent electrocatalytic activity is accounted by the surface metal-Cl species that facilitate charge transfer and downshift the d-band center.Results from this study highlight the unique advantages of MIH in rapid sample preparation,where residual anion ligands play a critical role in manipulating the electronic properties of the metal surfaces and the eventual electrocatalytic activity.