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A flat-foldable equiangular spiral folding pattern inspired by sunflowers for deployable structures

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Chinese Journal of Aeronautics 2024年第6期37卷 425-438页

作者： Shuangqing yu Jinguo liu Pengyuan ZHAO Yingying TANG State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China

Flasher origami pattern has been widely utilized to improve the stowage efficiency of deployable ***,flasher origami cannot be folded fully flat,and they still have great potential for optimization in terms of storage volume and folding *** this paper,a flat foldable equiangular spiral folding pattern inspired by the sunflower disk is ***,a parametric design method for this equiangular spiral crease diagram is introduced in ***,a kinematic model of the equiangular spiral folding pattern is established based on the kinematic equivalence between rigid origami and spherical linkages.A simulation of the developed model demonstrates that the equiangular spiral folding pattern can be folded *** the folded ratio as an evaluation index,the calculated results and experiments show that the equiangular spiral crease pattern can yield fewer creases and improve stowage efficiency in comparison to flasher origami *** spiral folding pattern can save a considerable amount of space and provide a new approach to spatially deployable structures.

关键词： Flasher origami Sunflower-inspired Deployable structures Flat-foldability Equiangular spiral folding pattern

MAVS Antagonizes Human Stem Cell Senescence as a Mitochondrial Stabilizer

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Research 2024年第2期2023卷 239-257页

作者： Cui Wang Kuan Yang Xiaoqian liu si Wang Moshi Song Juan Carlos Izpisua Belimonte Jing Qu Guang-Hui liu Weiqi Zhang CAS Key Laboratory of Genomic and Precision Medicine Beijng Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China sino-Danish College University of Chinese Academy of SciencesBeijing 101408China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of Sciences Beijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Bejing 100101China Advanced Innovation Center for Human Brain Protection National Clinical Research Center for Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Altos Labs Inc.San DiegoCA 94022USA

Mitochondrial dysfunction is a hallmark feature of cellular senescence and organ ***,we asked whether the mitochondrial antiviral signaling protein(MAVS),which is essential for driving antiviral response,also regulates human stem cell *** answer this question,we used CRISPR/Cas9-mediated gene editing and directed differentiation techniques to generate various MAVS-knockout human stem cell *** found that human mesenchymal stem cells(hMSCs)were sensitive to MAVS deficiency,as manifested by accelerated senescence *** uncovered that the role of MAVS in maintaining mitochondrial structural integrity and functional homeostasis depends on its interaction with the guanosine triphosphatase optic atrophy type 1(OPA1).Depletion of MAVS or OPA1 led to the dysfunction of mitochondria and cellular senescence,whereas replenishment of MAVS or OPA1 in MAVS-knockout hMSCs alleviated mitochondrial defects and premature senescence *** together,our data underscore an uncanonical role of MAVS in safeguarding mitochondrial homeostasis and antagonizing human stem cell senescence.

关键词： CRISPR/Cas9 homeostasis Mitochondrial

Spatiotemporal variation of land surface temperature and its driving factors in Xinjiang,China

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Journal of Arid Land 2024年第3期16卷 373-395页

作者： ZHANG Mingyu CAO yu ZHANG Zhengyong ZHANG Xueying liu Lin CHEN Hongjin GAO yu yu Fengchen liu Xinyi College of Sciences Shihezi UniversityShihezi 832000China Key Laboratory of Oasis Town and Mountain-Basin System Ecology Xinjiang Production and Construction CorpsShihezi 832000China Yantai Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264003China

Land surface temperature(LST) directly affects the energy balance of terrestrial surface systems and impacts regional resources, ecosystem evolution, and ecosystem structures. Xinjiang Uygur Autonomous Region is located at the arid Northwest China and is extremely sensitive to climate change. There is an urgent need to understand the distribution patterns of LST in this area and quantitatively measure the nature and intensity of the impacts of the major driving factors from a spatial perspective, as well as elucidate the formation mechanisms. In this study, we used the MOD11C3 LST product developed on the basis of Moderate Resolution Imaging Spectroradiometer(MODIS) to conduct regression analysis and determine the spatiotemporal variation and differentiation pattern of LST in Xinjiang from 2000 to 2020. We analyzed the driving mechanisms of spatial heterogeneity of LST in Xinjiang and the six geomorphic zones(the Altay Mountains, Junggar Basin, Tianshan Mountains, Tarim Basin, Turpan-Hami(Tuha) Basin, and Pakakuna Mountain Group) using geographical detector(Geodetector) and geographically weighted regression(GWR) models. The warming rate of LST in Xinjiang during the study period was 0.24℃/10a, and the spatial distribution pattern of LST had obvious topographic imprints, with 87.20% of the warming zone located in the Gobi desert and areas with frequent human activities, and the cooling zone mainly located in the mountainous areas. The seasonal LST in Xinjiang was at a cooling rate of 0.09℃/10a in autumn, and showed a warming trend in other seasons. Digital elevation model(DEM), latitude, wind speed, precipitation, normalized difference vegetation index(NDVI), and sunshine duration in the single-factor and interactive detections were the key factors driving the LST changes. The direction and intensity of each major driving factor on the spatial variations of LST in the study area were heterogeneous. The negative feedback effect of DEM on the spatial differentiation o

关键词： land surface temperature MOD11C3 climate change geographical detector(Geodetector) geographically weighted regression(GWR) source-sink effect Xinjiang

Development of Fixture Layout Optimization for Thin-Walled Parts:A Review

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 15-39页

作者： Changhui liu Jing Wang Binghai Zhou Jianbo yu Ying Zheng Jianfeng liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao Shipbuilding Co. Ltd.Shanghai 200137China

An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past ***,few papers systematically review these *** analyzing existing literature,this paper summarizes the process of fixture layout optimization and the methods *** process of optimization is made up of optimization objective setting,assembly variation/deformation modeling,and fixture layout *** paper makes a review of the fixture layout for thin-walled parts according to these three ***,two different kinds of optimization objectives are *** usually consider in-plane variations or out-of-plane deformations when designing ***,modeling methods for assembly variation and deformation are divided into two categories:Mechanism-based and data-based *** common methods are discussed *** that,optimization algorithms are reviewed *** are two kinds of optimization algorithms:Traditional nonlinear programming and heuristic ***,discussions on the current situation are *** research direction of fixture layout optimization in the future is discussed from three aspects:Objective setting,improving modeling accuracy and optimization ***,a new research point for fixture layout optimization is *** paper systematically reviews the research on fixture layout optimization for thin-walled parts,and provides a reference for future research in this field.

关键词： Thin-walled parts Assembly quality Fixture layout optimization Modeling methods Optimization algorithms

Mechanical characteristics and reservoir stimulation mechanisms of the Gulong shale oil reservoirs, the northern Songliao Basin

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Petroleum Science 2024年第3期21卷 2023-2036页

作者： si-Wei Meng Jia-Ping Tao Tian-Jiao Li Dong-Xu Li Su-Ling Wang liu Yang Xin liu Li-Hao Liang He liu PetroChina Research Institute of Petroleum Exploration Development Beijing100083China National Key Laboratory of Continental Shale Oil Daqing 163002HeilongjiangChina Dalian University of Technology Dalian116024LiaoningChina PetroChina Daqing Oilfield Co.Ltd. Daqing163002HeilongjiangChina Northeast Petroleum University Daqing163002HeilongjiangChina China University of Mining and Technology(Beijing) Beijing100083China

Shale oil of the Qingshankou Formation of the Gulong Sag,the northern Songliao Basin,represents the first attempt at large-scale development of pure-shale-type shale oil in *** integrating the multiscale refined reservoir characterization with macro-micro-scale mechanical testing,it is clarified that the Gulong shale is characterized by high clay mineral content,high rock plasticity,highly-developed bedding,and prominent mechanical anisotropy.A three-dimensional(3D)fracture propagation model of hydraulic fracturing was built for the Gulong shale,which fully captures the hydraulic fracture distribution pattern affected by the high bedding density,in-situ stress,and fracturing treatment *** research showed that due to influences of bedding,hydraulic fracturing in the Gulong shale forms a complex fracture morphology featuring the main fracture with multiple perpendicular branches that have different lengths(like the outdoor directional TV antenna);however,the vertical propagation of fractures is inhibited,and the fracture height is commonly less than 10 *** limited stimulated reservoir volume(SRV)is the main problem facing the fracturing stimulation of the Gulong shale *** density has vital effects on fracture morphology,so case-specific fracturing designs shall be developed for shale intervals with different bedding development *** reservoirs with welldeveloped bedding,it is suggested to properly increase the perforation cluster spacing and raise the volume and proportions of viscous fluids of the pad,so as to effectively promote vertical fracture propagation and improve reservoir stimulation *** study integrates multi-scale fine reservoir characterization and macro-micro-scale mechanical testing,as well as the construction and numerical simulation of hydraulic fracturing models for high-density layered shale reservoirs,providing a new approach and methodological framework for the fracturing research of high-density layer

关键词： Shale oil Hydraulic fracturing High bedding density Fracture propagation model

Characterization of the pheromone receptors in Mythimna loreyi reveals the differentiation of sex pheromone recognition in Mythimna species

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Insect Science 2024年第1期31卷 173-185页

作者： Chan Wang Lei liu Tian-yu Huang yu Zhang Yang liu Gui-Rong Wang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina Guangdong Laboratory of Lingnan Modern Agriculture ShenzhenGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenChina School of Forestry Northeast Forestry UniversityHarbinChina Key Laboratory of Biohazard Monitoring Green Prevention and Control for Artificial GrasslandMinistry of Agriculture and Rural AffairsInstitute of Grassland Research of Chinese Academy of Agricultural SciencesInner Mongolia HohhotChina

Pheromone receptors(PRs)are key proteins in the molecular mechanism of pheromone recognition,and exploring the functional differentiation of PRs between closely related species helps to understand the evolution of moth mating *** components of the agricultural pest Mythimna loreyi have turned into(Z)-9-tetradecen-1-yl acetate(Z9-14:OAc),(Z)-7-dodecen-1-yl acetate(Z7-12:OAc),and(Z)-11-hexadecen-1-yl acetate,while the composition differs from that of *** in the genus *** understand the molecular mechanism of pheromone recognition,we sequenced and analyzed antennal transcriptomes to identify 62 odorant receptor(OR)*** expression levels of all putative ORs were analyzed using differentially expressed gene *** candidate PRs were quantified and functionally characterized in the Xenopus oocytes ***6 and MlorPR3 were determined to be the receptors of major and minor components Z9-14:OAc and Z7-12:***1 and female antennae(FA)-biased MlorPR5 both possessed the ability to detect pheromones of sympatric species,including(Z,E)-9,12-tetradecadien-1-ol,(Z)-9-tetradecen-1-ol,and(Z)-*** on the comparison of PR functions between *** and ***,we analyzed the differentiation of pheromone recognition mechanisms during the evolution of the mating systems of 2 Mythimna species.

关键词： antennal transcriptome Mythimna loreyi pheromone receptor sex pheromone Xenopus oocyte

Optimization of Fixture Number in Large Thin-Walled Parts Assembly Based on IPSO

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 213-227页

作者： Changhui liu Jing Wang Ying Zheng Ke Jin Jianbo yu Jianfeng liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao Shipbuilding Co. Ltd.Shanghai 200137China

There are lots of researches on fixture layout optimization for large thin-walled *** researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of ***,how to determine the number of fixtures is *** most cases,the number of fixtures located on large thin-walled parts is determined based on engineering experience,which leads to huge fixture number and extra ***,this paper constructs an optimization model to minimize the number of *** constraints are set in the optimization model to ensure that the part deformation is within the surface profile *** addition,the assembly gap between two parts is also *** conduct the optimization,this paper develops an improved particle swarm optimization(IPSO)algorithm by integrating the shrinkage factor and adaptive inertia *** the algorithm,particles are encoded according to the fixture *** dimension of the particle is assigned to a sub-region by constraining the optional position range of each fixture to improve the optimization ***,a case study on ship curved panel assembly is provided to prove that our method can optimize the number of fixtures while meeting the assembly quality *** research proposes a method to optimize the number of fixtures,which can reduce the number of fixtures and achieve deformation control at the same time.

关键词： Assembly quality Large thin-walled parts Fixture layout PSO FEM

Preoperative serum cortisone levels are associated with cognition in preschool‑aged children with tetralogy of Fallot after corrective surgery:new evidence from human populations and mice

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World Journal of Pediatrics 2024年第2期20卷 173-184页

作者： si-yu Ma yu-Ting liu yue-Shuang Cun Qiang Wang Ming-Cui Fu Ke-De Wu Xin-yu Cai Shu-Ting Cheng Nishant Patel Min Da Liang Hu Zhuoga Deqin Xue-Jun Kang Ming Yang Xu-Ming Mo Department of Cardiothoracic Surgery Children’s Hospital of Nanjing Medical University72 Guangzhou RoadNanjing 210008China Department of Radiology Children’s Hospital of Nanjing Medical University72 Guangzhou RoadNanjing 210008China Key Laboratory of Child Development and Learning Science Research Center For Learning ScienceSchool of Biological Sciences&Medical EngineeringMinistry of EducationSoutheast UniversityNanjing 210096China Medical School of Nanjing University Nanjing 210093China

Background Tetralogy of Fallot(TOF)is the most common cyanotic congenital heart *** with TOF would be confronted with neurological impairment across their *** study aimed to identify the risk factors for cerebral morphology changes and cognition in postoperative preschool-aged children with *** We used mass spectrometry(MS)technology to assess the levels of serum metabolites,Wechsler preschool and primary scale of intelligence-Fourth edition(WPPsi-Ⅳ)index scores to evaluate neurodevelopmental levels and multimodal magnetic resonance imaging(MRI)to detect cortical morphological *** Multiple linear regression showed that preoperative levels of serum cortisone were positively correlated with the gyrification index of the left inferior parietal gyrus in children with TOF and negatively related to their lower visual spaces index and nonverbal ***,preoperative SpO_(2) was negatively correlated with levels of serum cortisone after adjusting for all ***,after intervening levels of cortisone in chronic hypoxic model mice,total brain volumes were reduced at both postnatal(P)11.5 and P30 *** Our results suggest that preoperative serum cortisone levels could be used as a biomarker of neurodevelopmental impairment in children with *** study findings emphasized that preoperative levels of cortisone could influence cerebral development and cognition abilities in children with TOF.

关键词： Cognition Cortisone MRI Neurodevelopment Tetralogy of Fallot

Climate warming is likely to weaken the performance of two-phase closed thermosyphon on the Qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第1期15卷 90-100页

作者： Guan-Li JIANG Zi-Teng FU Xin-yu MEN Hong-Ting ZHAO si-Ru GAO Yong-Zhi LI Qing-Bai WU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Beiluhe Observation and Research Station on Frozen Soil Engineering and Environment in the Qinghai-Tibet Plateau Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Muli Field Scientific Observation and Research Station for Gas Hydrate China Geological SurveyBeijing 100083China University of Chinese Academy of Sciences Beijing 100049China School of Civil Engineering and Architecture Jiaxing Nanhu UniversityJiaxing 314001China

Over the years,numerous geotechnical approaches have been implemented to mitigate the adverse effects of climate warming on various infrastructures in the permafrost region of the Qinghai-Tibet Plateau(QTP),such as the Qinghai-Tibet Highway and Railway,and achieved the expected engineering ***,little attention has been given to whether the performance of these geotechnical approaches has changed during the ongoing process of climate *** investigate the performance variation of one of these geotechnical approaches,which is two-phase closed thermosyphon(TPCT),during sustained climate warming,we conducted a statistical analysis of soil temperature monitoring data in 2003-2020 from eight regular embankments and six TPCT embankments in our permafrost monitoring *** results indicate that TPCT undeniably has a cooling effect on the permafrost beneath embankments,even rapidly eliminated previously formed taliks beneath ***,further analysis reveals that the performance of TPCT has been weakening during sustained climate warming,which has confirmed by the re-forming of the taliks beneath embankment where they had been previously *** on the current understanding,we attributed the weakening of thermosyphon performance to a significant reduction in the air temperature freezing index caused by ongoing climate *** this study,we aimed to draw attention to the evolving performance of geotechnical approaches in permafrost regions amid climate warming,prompting necessary engineering innovations to address this situation and ensure the sustainable development of the permafrost region on the QTP.

关键词： Two-phase closed thermosyphon Climate warming Supra-permafrost talik Permafrost degradation Qinghai-Tibet Highway