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Caseinolytic mitochondrial matrix peptidase X is essential for homologous chromosome synapsis and recombination during meiosis of male mouse germ cells

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Asian Journal of Andrology 2024年第2期26卷 165-174页

作者： Hai-Wei feng Yu Zhao Yan-ling Gao dong-Teng Liu Li-Jun Huo Key Laboratory of Agricultural Animal Genetics Breeding and ReproductionEducation Ministry of ChinaCollege of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China Shenzhen Key Laboratory of Fertility Regulation Reproductive Medicine CenterThe University of Hong Kong-Shenzhen HospitalShenzhen 518053China Maternal-Fetal Medicine Institute Department of Obstetrics and GynaecologyShenzhen Baoan Women's and Children's HospitalJinan UniversityShenzhen 518100China Department of Obstetrics and Gynaecology Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong SARChina

Meiosis is the process of producing haploid gametes through a series of complex chromosomal events and the coordinated action of various proteins.The mitochondrial protease complex(ClpXP),which consists of caseinolytic mitochondrial matrix peptidase X(ClpX)and caseinolytic protease P(ClpP)and mediates the degradation of misfolded,damaged,and oxidized proteins,is essential for maintaining mitochondrial homeostasis.ClpXP has been implicated in meiosis regulation,but its precise role is currently unknown.In this study,we engineered an inducible male germ cell-specific knockout caseinolytic mitochondrial matrix peptidase X(Clpx^(cKO))mouse model to investigate the function of ClpX in meiosis.We found that disrupting Clpx in male mice induced germ cell apoptosis and led to an absence of sperm in the epididymis.Specifically,it caused asynapsis of homologous chromosomes and impaired meiotic recombination,resulting in meiotic arrest in the zygotene-to-pachytene transition phase.The loss of ClpX compromised the double-strand break(DSB)repair machinery by markedly reducing the recruitment of DNA repair protein RAD51 homolog 1(RAD51)to DSB sites.This dysfunction may be due to an insufficient supply of energy from the aberrant mitochondria in Clpx^(cKO) spermatocytes,as discerned by electron microscopy.Furthermore,ubiquitination signals on chromosomes and the expression of oxidative phosphorylation subunits were both significantly attenuated in Clpx^(cKO) spermatocytes.Taken together,we propose that ClpX is essential for maintaining mitochondrial protein homeostasis and ensuring homologous chromosome pairing,synapsis,and recombination in spermatocytes during meiotic prophase I.

关键词： ClpX homologous chromosome meiosis mitochondrial recombination synapsis

Functionalization design of zinc anode for advanced aqueous zinc-ion batteries

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SusMat 2024年第2期4卷 89-124页

作者： Ziyi feng Yang feng Fangfang Fan Dezhao Deng Han dong Shude Liu ling Kang Seong Chan Jun ling Wang Jing Zhu Lei Dai Zhangxing He School of Chemical Engineering North China University of Science and TechnologyTangshanChina State Key Laboratory of Advanced Chemical Power Sources College of ChemistryNankai UniversityTianjinChina Shanghai Frontiers Science Center of Advanced Textiles College of TextilesDonghua UniversityShanghaiChina Shanghai Key Laboratory of Multidimensional Information Processing East China Normal UniversityShanghaiChina School of Mechanical Engineering Yonsei UniversitySeoulSouth Korea

Rechargeable aqueous zinc-ion batteries(AZIBs)offer high energy density,low cost,and are environmentally friendly,rendering them potential energy storage devices.However,dendrite growth on the zinc anode and numerous side reac-tions during operation challenge their commercialization.Recent advancements have introduced various materials for the functionalization of zinc anodes.These developments effectively mitigate the performance degradation of zinc anode,enhancing both its cycle stability and the overall performance of AZIBs.Herein,the construction of functionalized zinc anodes is discussed,current materials(including organic,inorganic and their composites)for modified zinc anodes are categorized,and the protective mechanism behind functionalized zinc anodes is analyzed.The study concludes by outlining the characteristics of materials suitable for dendritic-free zinc anode construction and the prospects for future development directions of functionalized zinc anodes in AZIBs.

关键词： anode functionalization inorganic materials organic materials zinc-ion batteries

New black-to-white hole solutions with improved geometry and energy conditions

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 30-43页

作者： Zhongwen feng Yi ling Xiaoning Wu Qingquan Jiang School of Physics and Astronomy China West Normal UniversityNanchong 637009China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China Institute of Mathematics Academy of Mathematics and System Science and Hua Loo-Keng Key Laboratory of MathematicsChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China

We construct new black-to-white hole solutions which connect the geometry of spacetime at some gluing surface inside the horizon.The continuity of the metric can be guaranteed up to the arbitrary order which is controlled by the power factor n.This sort of black-to-white holes is characterized by the sub-Planckian scalar curvature,independent of the mass of black-to-white holes.More importantly,we show that the energy condition is only violated within a small region near the gluing surface.The geodesics of particles within the region from black hole to white hole is also analyzed.It turns out that the matter falling into the black hole may pass through the center without singularity and come out from the white hole.This scenario provides novel ideas for understanding the information loss paradox in traditional black hole physics.

关键词： regular black hole energy condition singularity quantum gravity

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Development of an automatic measurement system using atmospheric pressure photoionization ultrahigh-resolution mass spectrometry and application for on-line analysis of particulate matter

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Journal of Environmental Sciences 2024年第4期138卷 516-530页

作者： Yayuan dong Ranran Liu ling Xie Xiaole Pan Yele Sun Lin Wu ZifaWang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional Atmospheric Environment Chinese Academy of SciencesInstitute of Urban EnvironmentXiamen 361021China

On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real time.Here we describe the development and application of an automatic measurement system that incorporates PM_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRMS analysis.Molecular formulas of detected organic compounds were deducted from the accurate(±10 ppm)molecular weights obtained at a mass resolution of 100,000,allowing the identification of small organic compounds in PM_(2.5).Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 pg.As a proof of principle,PM_(2.5)samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the system.The automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 hr.The detected organic compounds comprised mainly CHON and CHN compounds below 350 m/z.Pronounced seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in winter.This result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in summer.Diurnal variation in signal intensity of each formula provides crucial information to reveal its source and formation pathway.In summary,the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM_(2.5).

关键词： PM_(2.5) Chemical composition On-line measurement technique High resolution mass spectrometry

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Enhanced cyclic stability of partially disordered spinel cathodes through direct fluorination with gaseous fluorine

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Rare Metals 2024年第4期43卷 1635-1646页

作者： Yong-Nian Ma ling-Chen Kong Shao-Shan Chen Yong Wang Li-dong Sun Cong Peng Meng-Meng Qin Yu Li Wei feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin University Institute of Advanced Technology and Equipment Beijing University of Chemical Technology

Spinel-type cathodes are considered an optimal substitute for conventional layered oxide cathodes owing to their use of inexpensive and earth-abundant manganese as the redox-active element.Moreover,the introduction of cation disorder can effectively suppress the detrimental two-phase reaction to realize high capacities in a wide voltage range.However,the continuous capacity decay during cycles has hindered the widespread application of these cathode materials.Inorganic fluorides exhibit excellent electrochemical stability at high voltage;therefore,in this study,the direct F2 gas reaction with a partially disordered spinel cathode(Li1.6Mn1.6O3.7F0.3,LMOF1.6) was initially applied to investigate the impacts of fluorination on the surface structure and electrochemical performances.The inorganic fluorinated layer,mainly containing LiF,was distributed uniformly on the surface of LMOF1.6nanoparticles after fluorination for an appropriate time without the turbulence caused by the valency of manganese cation,which improved the capacity retention and rate capability by the suppression of structural damage,parasitic reaction,and cation dissolution.The LMOF1.6cathode fluorinated for 0.5 h exhibited a capacity of283.6 mAh·g-1at 50 mA·g-1and an enhanced capacity retention of 29.6% after 50 cycles in the voltage range of1.5-4.8 V,as compared to the pristine LMOF1.6 with only27.9% capacity retention.

关键词： Spinel-type cathodes Direct fluorination Capacity retention ability High rate capability

Tomographic particle image velocimetry measurement on three-dimensional swirling flow in dual-stage counter-rotating swirler

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Chinese Journal of Aeronautics 2024年第3期37卷 7-20页

作者： Yuyang ZHOU ling dong Mingtao SHANG Jibao LI Akira RINOSHIKA Key Laboratory of Fluid Mechanics of Ministry of Education Beihang UniversityBeijing 100191China School of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai 201620China AECC Commercial Aircraft Engine Co. Ltd.Shanghai 200241China Department of Mechanical Systems Engineering Yamagata UniversityYamagata 992-8510Japan

Three-Dimensional(3D)swirling flow structures,generated by a counter-rotating dualstage swirler in a confined chamber with a confinement ratio of 1.53,were experimentally investigated at Re=2.3×10^(5)using Tomographic Particle Image Velocimetry(Tomo-PIV)and planar Particle Image Velocimetry(PIV).Based on the analysis of the 3D time-averaged swirling flow structures and 3D Proper Orthogonal Decomposition(POD)of the Tomo-PIV data,typical coherent flow structures,including the Corner Recirculation Zone(CRZ),Central Recirculation Zone(CTRZ),and Lip Recirculation Zone(LRZ),were extracted.The counter-rotating dual-stage swirler with a Venturi flare generates the independence process of vortex breakdown from the main stage and pilot stage,leading to the formation of an LRZ and a smaller CTRZ near the nozzle outlet.The confinement squeezes the CRZ to the corner and causes a reverse rotation flow to limit the shape of the CTRZ.A large-scale flow structure caused by the main stage features an explosive breakup,flapping,and Precessing Vortex Core(PVC).The explosive breakup mode dominates the swirling flow structures owing to the expansion and construction of the main jet,whereas the flapping mode is related to the wake perturbation.Confinement limits the expansion of PVC and causes it to contract after the impacting area.

关键词： Coherent structures Dual-stage counter-rotating swirler cup Precessing vortex core Proper orthogonal decomposition Swirling flow Tomographic particle image velocimetry

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Differences in insomnia-related self-reported outcomes among elderly hospitalized patients

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World Journal of Psychiatry 2024年第5期14卷 686-694页

作者： Xia Ding ling-Xia Qi dong-Yun Sun Department of Gangzha General Medical Center The Affiliated Hospital of Nantong UniversityNantong 226000Jiangsu ProvinceChina Department of Anesthesiology and Surgery The Affiliated Hospital of Nantong UniversityNantong 226000Jiangsu ProvinceChina Department of Ophthalmic Surgery Room The Affiliated Hospital of Nantong UniversityNantong 226000Jiangsu ProvinceChina

Insomnia is among the most common sleep disorders worldwide.Insomnia in older adults is a social and public health problem.Insomnia affects the physical and mental health of elderly hospitalized patients and can aggravate or induce physical illnesses.Understanding subjective feelings and providing reasonable and standardized care for elderly hospitalized patients with insomnia are urgent issues.AIM To explore the differences in self-reported outcomes associated with insomnia among elderly hospitalized patients.METHODS One hundred patients admitted to the geriatric unit of our hospital between June 2021 and December 2021 were included in this study.Self-reported symptoms were assessed using the Athens Insomnia Scale(AIS),Generalized Anxiety Disorder Scale-7(GAD-7),Geriatric Depression Scale-15(GDS-15),Memorial University of Newfoundland Scale of Happiness(MUNSH),Barthel Index Evaluation(BI),Morse Fall Scale(MFS),Mini-Mental State Examination,and the Short Form 36 Health Survey Questionnaire(SF-36).Correlation coefficients were used to analyze the correlation between sleep quality and self-reported symptoms.Effects of insomnia was analyzed using Logistic regression analysis.RESULTS Nineteen patients with AIS≥6 were included in the insomnia group,and the incidence of insomnia was 19%(19/100).The remaining 81 patients were assigned to the non-insomnia group.There were significant differences between the two groups in the GDA-7,GDS-15,MUNSH,BI,MFS,and SF-36 items(Pling(P<0.05).Subjective well-being and quality of life were poorer in the insomnia group than in the control group.The AIS scores positively correlated with the GAD-7,GDS-15,and MFS scores in elderly hospitalized patients with insomnia(P<0.05).Logistic regression analysis showed that GDS-15≥5 was an independent risk factor for insomnia in elderly hospitalized patients(P<0.05).C

关键词： Elderly hospitalized patients Insomnia Self-reported outcomes Symptoms Subjective feelings Correlation

Reinforcement Learning-Based Dynamic Order Recommendation for On-Demand Food Delivery

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Tsinghua Science and Technology 2024年第2期29卷 356-367页

作者： Xing Wang ling Wang Chenxin dong Hao Ren Ke Xing Department of Automation Tsinghua UniversityBeijing 100080China School of Mechanical and Automotive Engineering Qingdao Hengxing University of Science and TechnologyQingdao 266100China Meituan Beijing 100015China

On-demand food delivery(OFD)is gaining more and more popularity in modern society.As a kernel order assignment manner in OFD scenario,order recommendation directly influences the delivery efficiency of the platform and the delivery experience of riders.This paper addresses the dynamism of the order recommendation problem and proposes a reinforcement learning solution method.An actor-critic network based on long short term memory(LSTM)unit is designed to deal with the order-grabbing conflict between different riders.Besides,three rider sequencing rules are accordingly proposed to match different time steps of the LSTM unit with different riders.To test the performance of the proposed method,extensive experiments are conducted based on real data from Meituan delivery platform.The results demonstrate that the proposed reinforcement learning based order recommendation method can significantly increase the number of grabbed orders and reduce the number of order-grabbing conflicts,resulting in better delivery efficiency and experience for the platform and riders.

关键词： on-demand food delivery order recommendation reinforcement learning actor-critic network long short term memory

Numerical study on the effective thermal conductivity and thermal tortuosity of porous media with different morphologies

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Science China Technological Sciences 2024年第6期67卷 1685-1694页

作者： DU Shen LI dong LI Meng-Jie HE Ya-ling Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power Engineering Xi’an Jiaotong University

Effective thermal conductivity and thermal tortuosity are crucial parameters for evaluating the effectiveness of heat conduction within porous media. The direct pore-scale numerical simulation method is applied to investigate the heat conduction processes inside porous structures with different morphologies. The thermal conduction performances of idealized porous structures are directly compared with real foams across a wide range of porosity. Real foam structures are reconstructed using X-ray computed tomography and image processing techniques, while Kelvin and Weaire-Phelan structures are generated through periodic unit cell reconstruction. The detailed temperature fields inside the porous structures are determined by solving the heat conduction equation at the pore scale. The results present that the equivalent thermal conductivity of Kelvin and Weaire-Phelan structures is similar to and greater than that of the real foam structure with the same strut porosity. The thermal tortuosity of real foam structure is relatively larger and the heat conduction path becomes straighter by adopting the anisotropic design. The thermal tortuosity of the fluid channels for Kelvin, Weaire-Phelan, and real foam structures is close to one. The thermal conductivity of porous structures with heat transfer fluid increases as the thermal conductivity ratio of fluid to solid becomes larger. A small porosity of porous media leads to a larger equivalent thermal conductivity due to the dominant contribution of porous skeleton in the heat conduction process. Correlations derived from parallel and series models, as well as the Maxwell-Eucken models,provide decent predictions of effective thermal conductivity, with an average error of less than 8% in the entire range of thermal conductivity ratio.

关键词： volumetric solar receiver porous morphology direct pore-scale simulation equivalent thermal conductivity thermal tortuosity empirical correlation