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Prevalence of prolonged grief disorder and its symptoms among bereaved individuals in China:a systematic review and meta-analysis

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General Psychiatry 2024年第2期37卷 177-188页

作者： Meng-di Yuan Jun-Fa liu Bao-Liang zhong Research Center for Psychological and Health Sciences China University of Geosciences(Wuhan)WuhanHubeiChina Department of Psychiatry Wuhan Mental Health CentreWuhanHubeiChina

Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary considerably.Aims This meta-analysis aims to estimate the prevalence of PGD and its symptoms among bereaved individuals in China.Methods We conducted a literature search in major Chinese and English databases from their inception to 4 October 2023,for cross-sectional studies on the prevalence of PGD or its symptoms in bereaved Chinese individuals.The risk of bias of the included studies and certainty of the evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data(‘JBI checklist’)and the Grading of Recommendations,Assessment,Development and Evaluations(GRADE),respectively.The‘metaprop’package in R V.4.1.2 was used to synthesise the prevalence.Results A total of 28 studies involving 10994 bereaved individuals were included in the analysis,with JBI checklist scores between 3 and 7.The combined prevalence(95%confidence interval)of PGD and its symptoms was 8.9%(4.2%to 17.6%)and 32.4%(18.2%to 50.8%),respectively.PGD and its symptoms were most prevalent among those who had lost their only child(22.7%)and those bereaved by earthquakes(80.4%),respectively.The GRADE system assigned a very low certainty level to the evidence for the pooled prevalence of PGD and its symptoms.Conclusions The pooled prevalence of PGD and its symptoms indicate a potential high need for grief counselling services among bereaved individuals in China.This need is particularly pronounced in those who have lost their only child and those bereaved due to earthquakes.Further methodologically rigorous studies are needed to provide more accurate prevalence estimates.PROSPERO registration number CRD42023432553.

关键词： symptoms prevalence analysis

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Predictability of the upper ocean heat content in a Community Earth System Model ensemble prediction system

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Acta Oceanologica Sinica 2024年第1期43卷 1-10页

作者： Ting liu Wenxiu zhong State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Atmospheric Sciences Sun Yat-Sen UniversityZhuhai 519082China

Upper ocean heat content(OHC)has been widely recognized as a crucial precursor to high-impact climate variability,especially for that being indispensable to the long-term memory of the ocean.Assessing the predictability of OHC using state-of-the-art climate models is invaluable for improving and advancing climate forecasts.Recently developed retrospective forecast experiments,based on a Community Earth System Model ensemble prediction system,offer a great opportunity to comprehensively explore OHC predictability.Our results indicate that the skill of actual OHC predictions varies across different oceans and diminishes as the lead time of prediction extends.The spatial distribution of the actual prediction skill closely resembles the corresponding persistence skill,indicating that the persistence of OHC serves as the primary predictive signal for its predictability.The decline in actual prediction skill is more pronounced in the Indian and Atlantic oceans than in the Pacific Ocean,particularly within tropical regions.Additionally,notable seasonal variations in the actual prediction skills across different oceans align well with the phase-locking features of OHC variability.The potential predictability of OHC generally surpasses the actual prediction skill at all lead times,highlighting significant room for improvement in current OHC predictions,especially for the North Indian Ocean and the Atlantic Ocean.Achieving such improvements necessitates a collaborative effort to enhance the quality of ocean observations,develop effective data assimilation methods,and reduce model bias.

关键词： ocean heat content prediction skill retrospective forecast experiment

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Tuning mechanical behaviors of highly entangled hydrogels with the random distribution of mobile entanglements

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 277-294页

作者： Jinlong liu di LU Bin CHEN Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China Beijing System Design Institute of Electro-Mechanic Engineering Beijing 100854China Intelligent Robotic Research Center Zhejiang LaboratoryHangzhou 310027China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Hangzhou 311100China

Highly entangled hydrogels exhibit excellent mechanical properties,including high toughness,high stretchability,and low hysteresis.By considering the evolution of randomly distributed entanglements within the polymer network upon mechanical stretches,we develop a constitutive theory to describe the large stretch behaviors of these hydrogels.In the theory,we utilize a representative volume element(RVE)in the shape of a cube,within which there exists an averaged chain segment along each edge and a mobile entanglement at each corner.By employing an explicit method,we decouple the elasticity of the hydrogels from the sliding motion of their entanglements,and derive the stress-stretch relations for these hydrogels.The present theoretical analysis is in agreement with experiment,and highlights the significant influence of the entanglement distribution within the hydrogels on their elasticity.We also implement the present developed constitutive theory into a commercial finite element software,and the subsequent simulations demonstrate that the exact distribution of entanglements strongly affects the mechanical behaviors of the structures of these hydrogels.Overall,the present theory provides valuable insights into the deformation mechanism of highly entangled hydrogels,and can aid in the design of these hydrogels with enhanced performance.

关键词： highly entangled hydrogel constitutive theory entanglement gamma distribution

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Mg-doped,carbon-coated,and prelithiated SiO_(x) as anode materials with improved initial Coulombic efficiency for lithium-ion batteries

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Carbon Energy 2024年第3期6卷 204-214页

作者： Bin liu Jie liu Cheng zhong Wenbin Hu Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) School of Materials Science and EngineeringTianjin UniversityTianjinChina Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjinChina Joint School of National University of Singapore and Tianjin University TianjinChina International Campus of Tianjin University Binhai New CityFuzhouChina

Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium silicates during the first cycle.In this work,we modify SiO_(x) by solid-phase Mg doping reaction using low-cost Mg powder as a reducing agent.We show that Mg reduces SiO_(2) in SiO_(x) to Si and forms MgSiO_(3) or Mg_(2)SiO_(4).The MgSiO_(3) or Mg_(2)SiO_(4) are mainly distributed on the surface of SiO_(x),which suppresses the irreversible lithium-ion loss and enhances the ICE of SiO_(x).However,the formation of MgSiO_(3) or Mg_(2)SiO_(4) also sacrifices the capacity of SiO_(x).Therefore,by controlling the reaction process between Mg and SiO_(x),we can tune the phase composition,proportion,and morphology of the Mg-doped SiO_(x) and manipulate the performance.We obtain samples with a capacity of 1226 mAh g^(–1) and an ICE of 84.12%,which show significant improvement over carbon-coated SiO_(x) without Mg doping.By the synergistical modification of both Mg doping and prelithiation,the capacity of SiO_(x) is further increased to 1477 mAh g^(–1) with a minimal compromise in the ICE(83.77%).

关键词： initial Coulombic efficiency lithium-ion batteries magnesium doping prelithiation silicon suboxide

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Weakly Polarized Organic Cation-Modified Hydrated Vanadium Oxides for High-Energy Efficiency Aqueous Zinc-Ion Batteries

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Nano-Micro Letters 2024年第7期16卷 169-186页

作者： Xiaoxiao Jia Chaofeng liu Zhi Wang di Huang Guozhong Cao Department of Materials Science and Engineering University of WashingtonSeattleWA 98195USA School of Materials Science and Engineering Tongji UniversityShanghai 201804People’s Republic of China

Vanadium oxides,par-ticularly hydrated forms like V_(2)O_(5)·nH_(2)O(VOH),stand out as promising cathode candidates for aqueous zinc ion batteries due to their adjustable layered structure,unique electronic characteristics,and high theoretical capacities.However,challenges such as vanadium dissolution,sluggish Zn^(2+)diffusion kinetics,and low operating voltage still hinder their direct application.In this study,we present a novel vanadium oxide([C_(6)H_(6)N(CH_(3))_(3)]_(1.08)V_(8)O_(20)·0.06H_(2)O,TMPA-VOH),developed by pre-inserting trimethylphenylammonium(TMPA+)cations into VOH.The incorporation of weakly polarized organic cations capitalizes on both ionic pre-intercalation and molecular pre-intercalation effects,resulting in a phase and morphology transition,an expansion of the interlayer distance,extrusion of weakly bonded interlayer water,and a substantial increase in V^(4+)content.These modifications synergistically reduce the electrostatic interactions between Zn^(2+)and the V-O lattice,enhancing structural stability and reaction kinetics during cycling.As a result,TMPA-VOH achieves an elevated open circuit voltage and operation voltage,exhibits a large specific capacity(451 mAh g^(-1)at 0.1 A g^(-1))coupled with high energy efficiency(89%),the significantly-reduced battery polarization,and outstanding rate capability and cycling stability.The concept introduced in this study holds great promise for the development of high-performance oxide-based energy storage materials.

关键词： Zinc-ion battery Vanadium oxide V_(2)O_(5)·nH_(2)O Pre-intercalation Interlayer engineering

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Resource Allocation in Multi-User Cellular Networks:A Transformer-Based Deep Reinforcement Learning Approach

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China Communications 2024年第5期21卷 77-96页

作者： Zhao di Zheng zhong Qin Pengfei Qin Hao Song Bin State Key Laboratory of Integrated Services Networks Xidian University710071China China Academy of Space Technology Beijing 100081China

To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing importance.In this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlink cellular scenario with the aim of maximizing system spectral efficiency while guaranteeing user fairness.We first model the MSMURA problem as a dual-sequence decision-making process,and then solve it by a novel Transformerbased deep reinforcement learning(TDRL)approach.Specifically,the proposed TDRL approach can be achieved based on two aspects:1)To adapt to the dynamic wireless environment,the proximal policy optimization(PPO)algorithm is used to optimize the multi-slot RA strategy.2)To avoid co-channel interference,the Transformer-based PPO algorithm is presented to obtain the optimal multi-user RA scheme by exploring the mapping between user sequence and resource sequence.Experimental results show that:i)the proposed approach outperforms both the traditional and DRL methods in spectral efficiency and user fairness,ii)the proposed algorithm is superior to DRL approaches in terms of convergence speed and generalization performance.

关键词： dynamic resource allocation multi-user cellular network spectrum efficiency user fairness

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Risk factors for brain injury in patients with exertional heatstroke:A 5-year experience

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Chinese Journal of Traumatology 2024年第2期27卷 91-96页

作者： Li zhong Ming Wu Zhe-Ying liu Yan liu Zhi-Feng liu Department of Traditional Chinese Medicine The First Affiliated HospitalGuizhou University of Chinese MedicineGuiyang550001China Department of Infection and Critical Care Medicine The Second People's Hospital of Shenzhen&First Affiliated Hospital of Shenzhen UniversityHealth Science CenterShenzhenGuangdong province518035China Department of Medical Critical Care Medicine General Hospital of Southem Theatre Command of PLA.Guangzhou510010China Guangdong Branch Center National Clinical Research Center for Geriatric Diseases(Chinese PLA General Hospital)Guangzhou510010China

Purpose:Minimal data exist on brain injury in patients with exertional heatstroke(EHS)in developing country.In this study,we explored the risk factors for brain injury induced by EHS 90-day after onset.Methods:A retrospective cohort study of patients with EHS was conducted in the intensive care unit of the General Hospital of Southern Theater Command of PLA in China from April 2014 to June 2019.Patients were divided into non-brain injury(fully recovered)and brain injury groups(comprising deceased patients or those with neurological sequelae).The brain injury group was further subdivided into a death group and a sequela group for detailed analysis.General information,neurological performance and information on important organ injuries in the acute stage were recorded and analysed.Multivariable logistic regression was used to identify risk factors for brain injury after EHS and mortality risk factors for brain injury,and Kaplan-Meier survival curve was used to evaluate the effect of the neurological dysfunction on survival.Results:Out of the 147 EHS patients,117 were enrolled,of which 96(82.1%)recovered,13(11.1%)died,and 8(6.8%)experienced neurological sequelae.Statistically significant differences were found between non-brain injury and brain injury groups in age,hypotension,duration of consciousness disorders,time to drop core body temperature below 38.5℃,lymphocyte counts,platelet counts,procalcitonin,alanine aminotransferase,aspartate aminotransferase,creatinine,cystatin C,coagulation parameters,international normalized ratio,acute physiology and chronic health evaluation II scores,sequential organ failure assessment(SOFA)scores,and Glasgow coma scale scores(all p<0.05).Multivariate logistic regression showed that age(OR=1.090,95%CI:1.02-1.17,p=0.008),time to drop core temperature(OR=8.223,95%CI:2.30-29.40,p=0.001),and SOFA scores(OR=1.676,95%CI:1.29-2.18,p<0.001)are independent risk factors for brain injury induced by EHS.The Kaplan-Meier curves suggest significantly prolonged survival(p<0.001)in patients with

关键词： Exertional heatstroke Brain injury Sequela Risk factors disorders of consciousness

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Q-homotopy analysis method for time-fractional Newell–Whitehead equation and time-fractional generalized Hirota–Satsuma coupled KdV system

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Communications in Theoretical Physics 2024年第3期76卷 70-83页

作者： di liu Qiongya Gu Lizhen Wang Center for Nonlinear Studies School of MathematicsNorthwest UniversityXi'an710127China

In this paper,two types of fractional nonlinear equations in Caputo sense,time-fractional Newell–Whitehead equation(FNWE)and time-fractional generalized Hirota–Satsuma coupled KdV system(HS-cKdVS),are investigated by means of the q-homotopy analysis method(q-HAM).The approximate solutions of the proposed equations are constructed in the form of a convergent series and are compared with the corresponding exact solutions.Due to the presence of the auxiliary parameter h in this method,just a few terms of the series solution are required in order to obtain better approximation.For the sake of visualization,the numerical results obtained in this paper are graphically displayed with the help of Maple.

关键词： fractional Newell-Whitehead equation fractional generalized Hirota-Satsuma coupled KdV system approximate solution q-homotopy analysis method

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Superior comprehensive properties of LaFe_(11.8)Si_(1.2)/Ce_(60)Co_(40) magnetocaloric composites

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Journal of Rare Earths 2024年第6期42卷 1073-1086,I0003页

作者： Xichun zhong Yuanxin Li Yucai Wu Jiaohong Huang Cuilan liu Jian liu zhongwu liu Minglong zhong Zhenchen zhong R.V.Ramanujan School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Baotou Research Institute of Rare Earths Baotou014030China Center for Advanced Solidification Technology School of Materials Science and EngineeringShanghai UniversityShanghai200444China Jiangxi KeyLaboratory for Rare Earth Magnetic Materials and Devices&Institute for Rare Earth Magnetic Materials and Devices(IREMMD) Jiangxi University of Science and TechnologyGanzhou341000China School of Materials Science and Engineering Nanyang Technological University639798Singapore Singapore-HUJ Alliance for Research and Enterprise(SHARE) The Smart Grippers for Soft Robotics(SGSR)ProgrammeCampus for Research Excellence and Technological Enterprise(CREATE)138602Singapor

LaFe_(11.8)Si_(1.2)/Ce_(60)Co_(40) composites were prepared by spark plasma sintering and subsequent diffusion annealing.A novel core-shell structure is observed with the LaFe11.8Si1.2 particles as the core and the(La,Ce)_(2)(Fe,Co,Si)_(17)(2:17)phase as the shell.As diffusion annealing time(t_(a))increases,this core-shell structure is replaced by the formation of the(La,Ce)_(1)(Fe,Co,Si)_(13) phase.Annealing at 1323 K for 12 h results in samples with(-ΔSM)^(max) of 9.30 J/(kg·K)(Δμ0H=2 T),good mechanical properties((σbc)^(max)=402 MPa,ε=4.21%)and thermal conductivity of 8.7 W/(m·K).Thus,bulk composites with excellent comprehensive properties for magnetic refrigeration are obtained in this work.

关键词： LaFe_(11.8)Si_(1.2)/Ce_(60)Co_(40)composites Spark plasma sintering diffusion annealing Microstructure evolution Magnetocaloric effect Rareearths

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Design method and experimental study of a cathode tool with an extremely high leveling ratio for electrochemical machining of blisk

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Chinese Journal of Aeronautics 2024年第4期37卷 593-608页

作者： Moqi SHEN Jia liu Jingtao WANG di ZHU College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To obtain final parts with the desired dimensional accuracy and repeatability via electrochemical machining(ECM), the machining process must enter an ECM balanced state. However,for the ECM processing of blisk, a key component of aerospace engines, the surface of the blade blank often has an uneven allowance distribution due to the narrow passage of the cascade. It is difficult to remedy this issue in subsequent processing steps, which is necessary to ensure the dimensional accuracy and repeatability of the final blade profile. To solve this problem, electrolytic machining must be preceded by electrolytic shaping, which requires cathode tools with large leveling ratios to quickly homogenize the blank surface of the blade. In this study, to obtain a cathode tool with an extremely high leveling ratio, a design method based on the variation in the electrode gap in the non-equilibrium electrolytic state is proposed, and a dissolution model based on the nonequilibrium state is established. In this design method, the allowance on the blank to be machined is first divided into many discrete allowances with the normal direction. The initial machining clearance, feed rate, and total machining time are then calculated using classical ECM equilibrium state theory based on the maximum allowance. Meanwhile, the point coordinates of the cathode tool at maximum allowance can be determined. The non-equilibrium model can then be used to calculate the relative coordinate positions corresponding to the remaining discrete allowances. Finally, the entire cathode tool profile is designed. Simulations, fundamental experiments, and blisk unit workpiece experiments were carried out to validate the design approach. In the simulated processing of the plane workpiece, the leveling ratio of the cathode tool designed by the proposed method(0.77)was 83% higher than that of the cathode tool designed using the traditional method. The simulation results were confirmed by processing experiments. In the machining of blisk unit workpieces with compl

关键词： Electrochemical machining(ECM) Non-equilibrium machining Large leveling ratios Cathode design Finite element simulation Blisk

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