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Development of Wave Water Simulator for Path Planning of Autonomous Robots in Constrained Environments
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作者 hui chen Mohammed A.H.Ali +6 位作者 Bushroa Abd Razak Zhenya Wang Yusoff Nukman Shikai Zhang Zhiwei Huang Ligang Yao Mohammad Alkhedher 《Computers, Materials & Continua》 2026年第4期2357-2385,共29页
Most existing path planning approaches rely on discrete expansions or localized heuristics that can lead to extended re-planning,inefficient detours,and limited adaptability to complex obstacle distributions.These iss... Most existing path planning approaches rely on discrete expansions or localized heuristics that can lead to extended re-planning,inefficient detours,and limited adaptability to complex obstacle distributions.These issues are particularly pronounced when navigating cluttered or large-scale environments that demand both global coverage and smooth trajectory generation.To address these challenges,this paper proposes a Wave Water Simulator(WWS)algorithm,leveraging a physically motivated wave equation to achieve inherently smooth,globally consistent path planning.In WWS,wavefront expansions naturally identify safe corridors while seamlessly avoiding local minima,and selective corridor focusing reduces computational overhead in large or dense maps.Comprehensive simulations and real-world validations-encompassing both indoor and outdoor scenarios-demonstrate that WWS reduces path length by 2%-13%compared to conventional methods,while preserving gentle curvature and robust obstacle clearance.Furthermore,WWS requires minimal parameter tuning across diverse domains,underscoring its broad applicability to warehouse robotics,field operations,and autonomous service vehicles.These findings confirm that the proposed wave-based framework not only bridges the gap between local heuristics and global coverage but also sets a promising direction for future extensions toward dynamic obstacle scenarios and multi-agent coordination. 展开更多
关键词 PDE-based wave propagation robot path planning obstacle avoidance wave water simulator laser simulator(LS)and generalized laser simulator(GLS) A*algorithm
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ZmCRK5A kinase enhances drought tolerance in maize via phosphorylation-dependent inhibition of ZmSMH4
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作者 Aifang Ma Yuemei Zhang +9 位作者 Yu Wang He Ma hui chen Yuanpeng Qi Manman Zhang Ziting Zhong Jinkui cheng Junsheng Qi Shuhua Yang Zhizhong Gong 《Journal of Integrative Plant Biology》 2026年第1期23-38,共16页
Drought stress orchestrates a phosphorylation-dependent signaling cascade that reprograms transcriptional networks to enhance crop resilience.Through a large-scale transgenic screening,we identified ZmCRK5A,a Ca^(2+)-... Drought stress orchestrates a phosphorylation-dependent signaling cascade that reprograms transcriptional networks to enhance crop resilience.Through a large-scale transgenic screening,we identified ZmCRK5A,a Ca^(2+)-independent calcium-dependent protein kinase(CDPK)-related kinase,as a master regulator of drought tolerance in maize.Mechanistically,ZmCRK5A directly phosphorylates the MYB transcriptional repressor ZmSMH4(Single MYB Histone 4)at three conserved serine residues(Ser42/43/59)within its SANT domain,as demonstrated by in vitro kinase assays and site-directed mutagenesis.This post-translational modification abolishes Zm SMH4's DNA-binding capacity to ACC cis-elements,thereby de-repressing the potassium influx channel gene Zm KCH1(K^(+)Channel 1).Functional validation revealed that Zm KCH1 overexpression confers drought resilience through optimized stomatal dynamics and water retention,whereas clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-generated zmkch1 mutants display hypersensitivity to water deficit.Crucially,field evaluations demonstrated preserved grain yield alongside enhanced drought tolerance in plants with activated Zm CRK5A-Zm SMH4-Zm KCH1 signaling.Our findings delineate a kinase-transcription factor-ion channel axis that dynamically fine-tunes drought responses while maintaining productivity,providing a strategic framework for engineering stress-adapted crops without yield penalties. 展开更多
关键词 drought response MAIZE PHOSPHORYLATION transcription factor ZmCRK5A ZmSMH4
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Dynamic pH-responsive DNA cube nanopores for adaptive transmembrane transport
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作者 Xiang chen hui chen +4 位作者 Yinfeng Li Shuangna Liu Jing Zheng Zhen Zou Jianbo Liu 《Science China Chemistry》 2026年第2期1002-1007,共6页
Developing lipid vesicles capable of self-regulation to adapt dynamically to environmental changes remains a significant challenge.In this study,we introduce a pH-responsive DNA-based transmembrane channel(p-cube)inte... Developing lipid vesicles capable of self-regulation to adapt dynamically to environmental changes remains a significant challenge.In this study,we introduce a pH-responsive DNA-based transmembrane channel(p-cube)integrated into lipid vesicles,enabling adaptive environmental responses.This nanopore,comprising four DNA strands,is anchored within lipid membranes via cholesterol modifications,with two semi-i-motif sequences strategically positioned at the apex.The i-motif structure exhibits pH-dependent folding behavior,allowing the DNA cube to reversibly open or close the nanopore in response to ambient pH variations.Fluorescence kinetic experiments demonstrated efficient,reversible modulation of transmembrane transport triggered by pH fluctuations.Furthermore,the capability of autonomous regulation under non-equilibrium conditions was validated by encapsulating glucose oxidase within vesicles and externally supplying glucose.The resulting proton generation from glucose oxidation induced pH-driven structural switching of the DNA nanopores,demonstrating environmental sensing and adaptive behavior reminiscent of natural cellular membranes.This intelligent and responsive transmembrane system holds significant potential for applications in targeted drug delivery,biosensing,and synthetic biology,providing novel approaches for precise environmental responsiveness and dynamic signaling regulation. 展开更多
关键词 SELF-REGULATION DNA nanostructures bionic transmembrane channe intelligent response regulation of substance transport
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Role of echinacoside in alleviating depressive-like symptoms in chronic unpredictable mild stressed mice via PI3K/AKT/Nrf2/HO-1 signaling pathway
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作者 Jin-Dong Mao hui chen +8 位作者 Min Wang Ye Wang Qian Zhang Qin-Fei Wang Kun Zhang Le Yang Xue Ma Chuan Wang Yu-Mei Wu 《Traditional Medicine Research》 2026年第6期60-72,共13页
Background:Depression,a prevalent mental health disorder,benefits from traditional Chinese medicine(TCM).Echinacoside(ECH),a natural phenolic compound extracted from Cistanche tubulosa and Echinacea angustifolia,exhib... Background:Depression,a prevalent mental health disorder,benefits from traditional Chinese medicine(TCM).Echinacoside(ECH),a natural phenolic compound extracted from Cistanche tubulosa and Echinacea angustifolia,exhibits neuroprotective and antioxidant properties.However,research on the potential mechanism of ECH’s antidepressant activity is limited.This study explored the antidepressant potential of ECH in mice subjected to chronic unpredictable mild stress(CUMS)and its underlying molecular mechanisms.Methods:Mice received ECH(10,20,40 mg/kg/d,i.p.)during the last 14 days of a 28-day CUMS protocol.The therapeutic effect was assessed via the sucrose preference test(SPT),tail suspension test(TST)and forced swim test(FST).Hematoxylin-eosin(H&E)and Nissl staining were employed to evaluate the changes of neuronal injury in hippocampus.Network pharmacology was used to explore the potential targets and pathway enrichment in ECH-mediated antidepression.The expression changes of PI3K/AKT/Nrf2/HO-1 were evaluated by Western blotting.Furthermore,the neuroprotection effects of ECH were assessed on cultured primary neurons injured by corticosterone(CORT)using CCK-8 assay.Results:The results indicated that ECH significantly alleviated depression-like behaviors in CUMS mice characterized as the improved sucrose intake in SPT,reduced immobility duration in TST and FST,reversed weight loss and hippocampal neuronal injury induced after CUMS.PI3K/AKT was selected as core targets by network pharmacology and supported by molecular docking and dynamics simulations.WB results indicated that ECH administration offered neuroprotection by recovering the expression levels of p-PI3K,p-AKT,Nrf2,and HO-1 in CUMS mice hippocampus.Moreover,ECH rescued CORT-induced neuron death in vitro by activating PI3K/AKT/Nrf2/HO-1 pathway,which was abolished by PI3K inhibitor LY294002.Conclusion:These findings demonstrated that ECH alleviated depressive-like behaviors via PI3K/AKT/Nrf2/HO-1 activation,highlighting its potential as a novel antidepressant. 展开更多
关键词 ECHINACOSIDE CUMS PI3K/AKT Nrf2/HO-1 neuroprotection
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In-situ visual microdamage detection in lead-based perovskite solar cells
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作者 Youzi Zhang Tong Wang +12 位作者 hui chen Jiabao Yang Yijin Wang Ranhao Yin Weizhe chen Jie Su Xiaotian Hu Wencheng Zhong Li Shang Feng Yan Maria-Magdalena Titirici Bingqing Wei Xuanhua Li 《Science China Chemistry》 2026年第2期1016-1022,共7页
Although lead(Pb)-based perovskite solar cells(PSCs)have garnered intense attention for their remarkable photovoltaic conversion efficiency,their commercial process is urgently in need of an effective damage-evaluatio... Although lead(Pb)-based perovskite solar cells(PSCs)have garnered intense attention for their remarkable photovoltaic conversion efficiency,their commercial process is urgently in need of an effective damage-evaluation system for the early diagnosis of faulty PSCs.The main cause of microdamage in perovskite films is the outflow of Pb,which significantly impacts device performance.However,no reliable correlation has been established between classical damage detection techniques and Pb detection,resulting in limited detection sensitivity.Here,we report an in situ visual microdamage evaluation method of PSCs by coating the device surface with a silica gel encapsulation layer containing porphyrin molecules.This detection technology enables high selectivity and sensitivity based on the strong complexation between the porphyrin ring and trace Pb outflow from degraded PSCs.By establishing the linear relationship between the fluorescence intensity and Pb concentration in PSCs,trace Pb outflow is pinpointed and quantified with a low detection limit of 0.65μg cm^(-2).An applet is developed for the insitu visual fluorescence detection method to facilitate the continuous real-time monitoring of series-type PSCs,thereby enabling the prompt identification and replacement of damaged PSCs and ensuring the swift restoration of high efficiency. 展开更多
关键词 perovskite solar cells microdamage evaluation in-situ visualization lead outflow fluorescence detection
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Exotic superconductivity in new topological kagome metal CsTi_(3)Bi_(5)
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作者 Jiali Liu Zhen Zhao +11 位作者 Hongqin Xiao Yuhang Zhang Zouyouwei Lu Jihu Lu Feng Wu chengjie Xu Hua Zhang hui chen Haitao Yang Ziyi Liu Xiaoli Dong Hongjun Gao 《Chinese Physics B》 2026年第2期264-270,共7页
We present a systematic investigation of the superconductivity in high-quality CsTi_(3)Bi_(5) single crystals by combining bulk property characterization and local-probe spectroscopy.Two successive superconducting tra... We present a systematic investigation of the superconductivity in high-quality CsTi_(3)Bi_(5) single crystals by combining bulk property characterization and local-probe spectroscopy.Two successive superconducting transitions are observed in this newly discovered kagome material.In the first stage,the diamagnetic response strengthens significantly from T_(c)~4.9 K to 4.6 K,followed by a broad transition below 4.6 K in the second stage.Moreover,different magnetic field dependences are observed for the two stages,where the first stage is field-insensitive while the second stage exhibits strong field dependence.The ultra-low magnetic field measurements indicate that the lower critical field H_(c1)(T)exhibits small anisotropy.Based on a comparative study of the superconducting state in CsBi2 and microscopic verification via scanning tunneling microscopy(STM),our results suggest the emergence of exotic and intrinsic superconductivity in this new titanium-based kagome superconductor,establishing it as a promising platform for further exploring the complexity of electronic states in the kagome lattice. 展开更多
关键词 kagome metal titanium-based material SUPERCONDUCTIVITY critical field
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In-situ Si particle-reinforced joints of hypereutectic Al−60Si alloys by ultrasonic-assisted soldering 被引量:2
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作者 Yuan-xing LI Xiang-bo ZHENG +3 位作者 Chao-zheng ZHAO Zong-tao ZHU Yu-jie BAI hui chen 《Transactions of Nonferrous Metals Society of China》 2025年第1期77-90,共14页
To improve the wettability of hypereutectic Al−60Si alloy and enhance the mechanical properties of the joints,Al−60Si alloy was joined by ultrasonic soldering with Sn-9Zn solder,and a sound joint with in-situ Si parti... To improve the wettability of hypereutectic Al−60Si alloy and enhance the mechanical properties of the joints,Al−60Si alloy was joined by ultrasonic soldering with Sn-9Zn solder,and a sound joint with in-situ Si particle reinforcement was obtained.The oxide film of Al−60Si alloy at the interface was identified by transmission electron microscopy(TEM)analysis as amorphous Al_(2)O_(3).The oxide of Si particles in the base metal was also alumina.The oxide film of Al−60Si alloy was observed to be removed by ultrasonic vibration instead of holding treatment.Si particle-reinforced joints(35.7 vol.%)were obtained by increasing the ultrasonication time.The maximum shear strength peaked at 99.5 MPa for soldering at 330℃with an ultrasonic vibration time of 50 s.A model of forming of Si particles reinforced joint under the ultrasound was proposed,and ultrasonic vibration was considered to promote the dissolution of Al and migration of Si particles. 展开更多
关键词 hypereutectic Al−60Si alloy ultrasonic-assisted soldering Si particle reinforcement Sn−9Zn solder
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Current status of endoscopic resection for small rectal neuroendocrine tumors 被引量:1
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作者 Jian-Ning Liu hui chen Nian Fang 《World Journal of Gastroenterology》 2025年第19期10-27,共18页
Rectal neuroendocrine tumor(rNET)is an indolent malignancy often detected during colonoscopy screening.The incidence of rNET has increased approximately 10-fold over the past 30 years.Most rNETs detected during screen... Rectal neuroendocrine tumor(rNET)is an indolent malignancy often detected during colonoscopy screening.The incidence of rNET has increased approximately 10-fold over the past 30 years.Most rNETs detected during screening endoscopy are small,measuring<10 mm.Current guidelines recommend endoscopic resection for small,well-differentiated rNET using modified endoscopic submucosal resection(mEMR)or endoscopic submucosal dissection.However,the optimal endoscopic treatment method remains uncertain.This paper summarizes the evidence on mEMR with submucosal stretching,mEMR without submucosal stretching,endoscopic submucosal dissection and endoscopic full-thickness resection.Given that rNETs often exhibit submucosal invasion,achieving adequate resection depth is crucial to ensure histological complete resection.mEMR with submucosal stretching appears favorable due to its high rate of histological complete resection,safety and convenience.Risk factors associated with lymph node and distant metastases are also discussed.A treatment algorithm is proposed to facilitate clinical decision-making. 展开更多
关键词 Rectal neuroendocrine tumor Endoscopic resection Endoscopic submucosal dissection Modified endoscopic mucosal resection Histological complete resection Resection depth Risk factor Treatment algorithm
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Enhancing efficiency and stability of inverted perovskite solar cells through synergistic suppression of multiple defects via poly(ionic liquid)-buried interface modification 被引量:1
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作者 Yijun Bai Tong Wang +9 位作者 Jiabao Yang Xingyu Pu Bingxiu Xue hui chen Xilai He Guangpeng Feng Shiyao Jia Jianbo Yin Qi Cao Xuanhua Li 《Journal of Materials Science & Technology》 2025年第9期281-288,共8页
The stability of perovskite solar cells(PSCs)is adversely affected by nonradiative recombination resulting from buried interface defects.Herein,we synthesize a polyionic liquid,poly(p-vinylbenzyl trimethylam-monium he... The stability of perovskite solar cells(PSCs)is adversely affected by nonradiative recombination resulting from buried interface defects.Herein,we synthesize a polyionic liquid,poly(p-vinylbenzyl trimethylam-monium hexafluorophosphate)(PTA),and introduce it into the buried interface of PSCs.The quaternary ammonium cation(N(-CH_(3))^(3+))in PTA can fill the vacancies of organic cations within the perovskite structure and reduce shallow energy level defects.Additionally,the hexafluorophosphate(PF6−)in PTA forms a Lewis acid-base interaction with Pb^(2+)in the perovskite layer,effectively passivating deep en-ergy level defects.Furthermore,hydrogen bonding can be established between organic cations and the PF6−anion,preventing the formation of shallow energy level defects.Through this synergistic mecha-nism,the deep and shallow energy level defects are effectively mitigated,resulting in improved device performance.As a result,the resulting treated inverted PSC exhibits an impressive power conversion ef-ficiency(PCE)of 24.72%.Notably,the PTA-treated PSCs exhibit remarkable stability,with 88.5%of the original PCE retained after undergoing heat aging at 85℃ for 1078 h,and 89.1%of the initial PCE main-tained following continuous exposure to light for 1100 h at the maximum power point.Synergistically suppressing multiple defects at the buried interface through the use of polyionic liquids is a promising way to improve the commercial viability of PSCs. 展开更多
关键词 Polyionic liquid Inverted perovskite solar cells Defect passivation High efficiency Operational stability
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Revealing effects of creep damage on high-temperature fatigue behavior for HfNbTiZr refractory high-entropy alloys:Experimental investigation and crystal-plasticity modelling 被引量:1
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作者 Long Xu hui chen +6 位作者 Yuefei Jia Dongpeng Wang Shiwei Wu Yandong Jia Gang Wang Zixu Guo Yilun Xu 《Journal of Materials Science & Technology》 2025年第28期134-150,共17页
Refractory high-entropy alloys(RHEAs)are promising for high-temperature applications due to their ex-ceptional mechanical properties at high temperatures.However,limited studies on their high-temperature fatigue behav... Refractory high-entropy alloys(RHEAs)are promising for high-temperature applications due to their ex-ceptional mechanical properties at high temperatures.However,limited studies on their high-temperature fatigue behavior hinder further development.This study systematically investigates the low-cycle fatigue(LCF)behavior of HfNbTiZr RHEA at room temperature(25℃)and elevated temperatures(350,450,and 600℃)through a combination of experimental analyses and dislocation-based damage-coupled crystal plasticity finite element(CPFE)simulations,to unveil the effects of creep damage on LCF behavior at varying temperatures.The results indicate that the LCF life dramatically decreases at an increased tem-perature,shifting from transgranular fatigue damage at lower temperatures(25-350℃)to a dual damage mechanism involving both intergranular fatigue and creep damage at higher temperatures(450-600℃).At 600℃,creep damage notably contributes to the accumulation of geometrically necessary dislocations(GNDs),crack initiation,and propagation at grain boundaries,and thus accelerates LCF failure.Compara-tive CPFE simulations reveal that creep damage significantly contributes to cyclic softening and reduction in elastic modulus,which also amplifies the strain localization under the LCF loading.The contribution of creep damage to the total stored energy density(SED)representing the overall damage increases with temperatures,accounting for 11%at 600℃.Additionally,CPFE simulations indicate that the creep dam-age notably influences the magnitude of GND density localized at grain boundaries.This study provides critical insights into the fatigue damage mechanisms of RHEAs,offering valuable guidance for their ap-plication in high temperatures. 展开更多
关键词 Refractory high-entropy alloys Elevated-temperature low-cycle fatigue Crystal plasticity finite element simulation Fatigue damage mechanisms Creep damage effect
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Mental Disorder Spectrum in Children and Adolescents from 2014-2022:A Nine-year Epidemiological and Clinical Trend 被引量:1
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作者 Xin-yi Ren Qi Jiang +1 位作者 hui chen Jun Tang 《Current Medical Science》 2025年第1期146-153,共8页
Objective This study aimed to analyse the trend of the mental disorder spectrum in children and adolescents from 2014 to 2022 in one city in Central China and to provide actionable recommendations for the prevention a... Objective This study aimed to analyse the trend of the mental disorder spectrum in children and adolescents from 2014 to 2022 in one city in Central China and to provide actionable recommendations for the prevention and management of mental disorders.Methods In this hospital-based retrospective study,we utilized child and adolescent medical records data from the Wuhan Mental Health Center from January 2014 to December 2022 and examined the top 5 mental disorders(schizophrenia,depressive episode,bipolar disorder,pervasive developmental disorder,and unspecified mood disorder)that accounted for the overall proportion of patients admitted.The rank and proportion of these mental disorders,demographic characteristics and disease indicators were analysed.Results There was a significant upwards trend in the number of children and adolescents diagnosed with mental disorders over the past 9 years,with a sharp decline in 2020 due to the COVID-19 pandemic,followed by a rebound in 2021 and a sustained level above prepandemic figures by 2022.The average age of hospitalization decreased significantly from 20.7 to 16.2 years,with a marked increase in the 12-17-year-old age group.The proportion of female hospitalizations increased from 39.2%to 55.2%,with a corresponding decrease in male hospitalizations.There was a notable decrease in the proportion of schizophrenia cases and an ascent of depressive episode to the most prevalent position.Conclusion This study emphasizes the critical need for targeted interventions and resources for severe mental disorders in children and adolescents and the importance of early detection and management of mental disorders to mitigate long-term effects on well-being and development. 展开更多
关键词 Mental disorders Adolescents Children HOSPITALIZATION
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鄂尔多斯盆地西南部致密砂岩储层微观裂缝特征及控制因素——以红河油田长8储层为例 被引量:35
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作者 吕文雅 曾联波 +4 位作者 周思宾 吉园园 梁丰 惠晨 尉加盛 《天然气地球科学》 EI CAS CSCD 北大核心 2020年第1期37-46,共10页
以鄂尔多斯盆地西南部红河油田长8致密砂岩储层为例,根据铸体薄片、扫描电镜分析,结合岩心和测井资料,采用地质学统计的方法,对微观裂缝的发育特征及控制因素进行系统分析,在此基础上,分析典型区块Q1井区的微观裂缝分布特征。结果表明:... 以鄂尔多斯盆地西南部红河油田长8致密砂岩储层为例,根据铸体薄片、扫描电镜分析,结合岩心和测井资料,采用地质学统计的方法,对微观裂缝的发育特征及控制因素进行系统分析,在此基础上,分析典型区块Q1井区的微观裂缝分布特征。结果表明:从地质成因上,该区致密砂岩储层的微观裂缝可以分为构造、成岩、构造-成岩和异常高压成因4种类型,其中以构造成因的微裂缝和构造-成岩成因的微裂缝为主,该区微观裂缝大部分为有效裂缝,少量无效裂缝被方解石、石英及炭质等充填。该区微观裂缝的发育程度受沉积作用、成岩作用、构造作用及异常高压作用控制。云母、岩屑等塑性成分含量越高,杂基含量越多,岩石颗粒越细,微裂缝发育程度越差;压实作用越强,越有利于构造-成岩成因的粒内缝、粒缘缝发育;随着胶结强度增强,粒内缝和粒缘缝发育程度降低,利于发育构造成因的微裂缝。典型区块Q1井区,在细砂岩强压实方解石强胶结相中,微观裂缝发育程度最强;其次为细砂岩强压实相和中-细砂岩方解石中胶结相;在细砂岩高岭石胶结相和绿泥石胶结中溶解相中,微观裂缝发育程度较弱;在泥岩中微观裂缝发育程度最弱。 展开更多
关键词 微观裂缝 成因类型 发育特征 控制因素 致密砂岩储层 鄂尔多斯盆地
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致密低渗透砂岩储层多尺度天然裂缝表征方法 被引量:41
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作者 吕文雅 曾联波 +5 位作者 陈双全 吕鹏 董少群 惠晨 李睿琦 王浩南 《地质论评》 CAS CSCD 北大核心 2021年第2期543-556,共14页
本文利用地表露头、岩芯、测井、三维地震和微观分析资料,根据多尺度裂缝的发育特征及不同资料的精度,探讨了多尺度裂缝的表征方法。致密低渗透砂岩储层发育多尺度天然裂缝,根据天然裂缝规模以及限制天然裂缝扩展延伸的岩石力学层界面,... 本文利用地表露头、岩芯、测井、三维地震和微观分析资料,根据多尺度裂缝的发育特征及不同资料的精度,探讨了多尺度裂缝的表征方法。致密低渗透砂岩储层发育多尺度天然裂缝,根据天然裂缝规模以及限制天然裂缝扩展延伸的岩石力学层界面,将天然裂缝分为大尺度裂缝、中尺度裂缝、小尺度裂缝和微尺度裂缝4级,不同尺度裂缝的发育特征存在较大差异。其中大尺度裂缝主要应用三维地震资料的叠后属性进行检测和表征;中小尺度裂缝在单井上可以应用岩芯、成像测井和常规测井相结合的方法进行表征,在平面上采用基于地质和测井约束的三维地震叠前各向异性分析以及储层地质力学相结合的方法进行综合预测和评价;微尺度裂缝一般应用铸体薄片、普通薄片、扫描电镜和三维CT扫描等微观分析方法进行观察描述,通过主控因素约束的方法进行预测。利用本文提出的多尺度裂缝表征方法实现了对鄂尔多斯盆地西南部致密砂岩储层多尺度裂缝表征,可为其它致密低渗透砂岩储层多尺度裂缝表征提供借鉴。 展开更多
关键词 天然裂缝 多尺度裂缝 表征方法 发育特征 致密低渗透砂岩储层
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隐源性缺血性脑卒中合并卵圆孔未闭的临床及影像学检查分析 被引量:21
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作者 王豪 孙园园 +5 位作者 邓雅琴 宋嫣 夏生根 陈晖 罗丽华 汪前洲 《中国现代医学杂志》 CAS 2019年第1期67-70,共4页
目的探讨卵圆孔未闭(PFO)伴隐源性缺血性脑卒中(CS)临床特点及不同影像学检查方法的优劣,研究卵圆孔未闭与隐源性脑卒中的相关性。方法选取2013年1月—2017年10月南昌大学第三附属医院收治的不明原因急性CS患者156例作为观察组,同时选... 目的探讨卵圆孔未闭(PFO)伴隐源性缺血性脑卒中(CS)临床特点及不同影像学检查方法的优劣,研究卵圆孔未闭与隐源性脑卒中的相关性。方法选取2013年1月—2017年10月南昌大学第三附属医院收治的不明原因急性CS患者156例作为观察组,同时选取与观察组年龄、性别相匹配的健康体检者148例作为对照组。两组均行经胸右心声学造影和经颅多普勒对比增强试验(cTCD)诊断PFO,并比较两组PFO及PFO合并房间隔瘤(ASA)的发病率。以手术封堵结果为金标准,分析观察组中经胸右心声学造影和经颅c TCD两种检测方法有无差异。结果观察组的PFO及PFO合并ASA检出率与对照组比较,差异有统计学意义(P<0.05),观察组高于对照组;以手术结果为金标准,cTCD检出PFO的敏感性、特异性、准确性分别为75.8%(50/66)、88.9%(80/90)和83.3%(130/156);经胸右心声学造影检出PFO的敏感性、特异性、准确性分别为90.9%(60/66)、94.4%(85/90)和92.9%(145/156)。经胸右心声学造影在不明原因急性CS患者中检出PFO的敏感性、准确性均优于c TCD(P<0.05)。结论不明原因急性CS患者PFO发病率高于正常健康人群,其检查方法首选右心声学造影。经胸右心声学造影及c TCD诊断卵圆孔未闭具有确切的临床应用价值。 展开更多
关键词 脑卒中 心血管造影术 超声检查 多普勒 经颅 卵圆孔未闭
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鄂尔多斯盆地合水地区长6致密砂岩储层现今地应力分布特征及其开发建议 被引量:18
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作者 刘建 惠晨 +4 位作者 樊建明 吕文雅 王继伟 尹陈 王浩南 《地质力学学报》 CSCD 北大核心 2021年第1期31-39,共9页
致密油藏物性差,非均质性强,现今地应力分布特征影响着致密油藏钻井施工、井网部署、压裂改造和注水管理等方面。文章根据微地震监测法分析了鄂尔多斯盆地合水地区长6储层单井现今地应力的方向,利用水力压裂资料分析了研究区单井现今地... 致密油藏物性差,非均质性强,现今地应力分布特征影响着致密油藏钻井施工、井网部署、压裂改造和注水管理等方面。文章根据微地震监测法分析了鄂尔多斯盆地合水地区长6储层单井现今地应力的方向,利用水力压裂资料分析了研究区单井现今地应力大小。在单井现今应力分析的基础上,结合合水地区长6储层构造、沉积、岩相特点建立了三维非均质地质模型,通过室内三轴岩石力学试验与施工数据,得到不同岩相的岩石物理参数,由此建立三维力学模型。利用Ansys进行有限元数值模拟,得到了研究区长6储层三维现今地应力分布模型,模拟结果表明水平最大主应力范围为34~42 MPa;水平最小主应力范围为25~36 MPa;水平差应力范围为3~10 MPa,并将结果与实际测量的井点应力大小进行对比,误差小于10%,模拟结果可信。分析模拟结果可知研究区现今地应力的分布主要受到了岩石物理力学性质差异的影响,而构造格架的影响较小。在结果分析的基础上,建议研究区布井时,不仅考虑地应力的影响,还应将天然裂缝作为影响因素考虑,同时,为尽可能地降低开发成本,在差应力相等的区域,油气工业井一般部署在应力值低的地方。 展开更多
关键词 现今地应力 三维数值模拟 致密储层 合水地区 开发建议
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Atomic Visualization of Bulk and Surface Superconductivity in Weyl Semimetal γ-PtBi_(2)
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作者 Hao Zhang hui chen +8 位作者 Zichen Huang Zi-Ang Wang Guangyuan Han Ruisong Ma Xiangde Zhu Wei Ning chengmin Shen Qing Huan Hong-Jun Gao 《Chinese Physics Letters》 2025年第12期307-313,共7页
A bulk superconductor hosting intrinsic surface superconductivity provides a unique platform for exploring Majorana bound states.Trigonal γ-PtBi_(2),a superconductor,is a promising candidate,as both surface supercond... A bulk superconductor hosting intrinsic surface superconductivity provides a unique platform for exploring Majorana bound states.Trigonal γ-PtBi_(2),a superconductor,is a promising candidate,as both surface superconducting gaps and topological surface states have been observed.However,the simultaneous presence of bulk and surface superconductivity has remained unresolved.In this study,we directly visualize coexisting bulk and surface superconducting gaps in trigonal PtBi_(2) using ultra-low-temperature scanning tunneling microscopy/spectroscopy.The bulk gap,Δ,is∼0.053 meV,with a critical temperature(T_(c))of∼0.5K and a critical field below 0.01 T,accompanied by a vortex lattice and vortex bound states and yielding a coherence length of∼200 nm.Remarkably,certain surface regions exhibit a much larger gap(Δ)of∼0.42 meV,persisting up to a T_(c)value of∼3K and surviving magnetic fields of up to 2 T,yet lacking a static vortex lattice.This coexistence of robust surface and bulk superconductivity establishes γ-PtBi_(2)as a unique platform for exploring the interplay between bulk and surface Cooper pairings in topological superconductors. 展开更多
关键词 bulk superconductor exploring majorana bound statestrigonal bulk superconductivity bulk surface superconductivity surface superconducting gaps surface superconductivity trigonal ptbi bulk surface superconducting gaps
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Tuning the Charge Density Wave and Low-Energy Magnetic States with Nanoscale Strains in GdTe_(3)
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作者 Zhong-Yi Cao hui chen +5 位作者 Guo-Jian Qian Yan-Hao Shi Qi Qi Xiang-He Han Hai-Tao Yang Hong-Jun Gao 《Chinese Physics Letters》 2025年第10期166-185,共20页
Recent advances in strain engineering have enabled unprecedented control over quantum states in strongly correlated magnetic systems.However,nanoscale strain modulation of charge density waves(CDWs)and magnetically ex... Recent advances in strain engineering have enabled unprecedented control over quantum states in strongly correlated magnetic systems.However,nanoscale strain modulation of charge density waves(CDWs)and magnetically excited states,which is crucial for atomically precise strain engineering and practical spintronic applications,remains unexplored.Here,we report the nanoscale strain effects on CDWs and low-energy electronic states in the van der Waals antiferromagnetic metal GdTe_(3),utilizing scanning tunneling microscopy/spectroscopy.Lowtemperature cleavage introduces local strains,resulting in the formation of nanoscale wrinkles on the GdTe_(3)surface.Atomic displacement analysis reveals two distinct types of wrinkles:Wrinkle-I,originating from unidirectional strain,and Wrinkle-II,dominated by shear strain.In Wrinkle-I,the tensile strain enhances the CDW gap,while the compressive strain induces a single low-energy magnetic state.Wrinkle-II switches the orientation of CDW,leading to the formation of an associated CDW domain wall.In addition,three low-energy magnetic states that exhibit magnetic field-dependent shifts and intensity variations emerge within the CDW gap around Wrinkle-II,indicative of a strain-tuned coupling between CDW order and localized 4f-electron magnetism.These findings establish nanoscale strain as a powerful tuning knob for manipulating intertwined electronic and magnetic excitations in correlated magnetic systems. 展开更多
关键词 nanoscale strain effects strain modulation charge density waves cdws control quantum states strain engineering practical spintronic applicationsremains scanning tunneling van der waals antiferromagnetic metal
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Integrating Internet Search Data and Surveillance Data to Construct Influenza Epidemic Thresholds in Hubei Province:A Moving Epidemic Method Approach
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作者 Caixia Dang Feng Liu +6 位作者 Hengliang Lyu Ziqian Zhao Sijin Zhu Yang Wang Yuanyong Xu Yeqing Tong hui chen 《Biomedical and Environmental Sciences》 2025年第9期1150-1154,共5页
Influenza,an acute respiratory infectious disease caused by the influenza virus,exhibits distinct seasonal patterns in China,with peak activity occurring in winter and spring in northern regions,and in winter and summ... Influenza,an acute respiratory infectious disease caused by the influenza virus,exhibits distinct seasonal patterns in China,with peak activity occurring in winter and spring in northern regions,and in winter and summer in southern areas[1].The World Health Organization(WHO)emphasizes that early warning and epidemic intensity assessments are critical public health strategies for influenza prevention and control.Internet-based flu surveillance,with real-time data and low costs,effectively complements traditional methods.The Baidu Search Index,which reflects flu-related queries,strongly correlates with influenza trends,aiding in regional activity assessment and outbreak tracking[2]. 展开更多
关键词 internet search data public health strategies moving epidemic method acute respiratory infectious disease early warning Hubei province epidemic intensity assessments surveillance data
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Smart gradient coating suitable for bone growth prepared on plasma-electrolytically oxidised Mg and its sequential degradation behaviour
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作者 Jiaping Han Kai Fu +6 位作者 Zhiqiang Jiang Hao Zhang Hongshan San hui chen Xiaopeng Lu Carsten Blawert Mikhail.L.Zheludkevich 《Journal of Magnesium and Alloys》 2025年第1期356-378,共23页
A gradient coating containing collagen and inorganic strontium/calcium phosphate(Sr/CaP)was fabricated on plasma-electrolytically oxidised magnesium via one-step cathodic electrodeposition.First,Sr-doped dicalcium pho... A gradient coating containing collagen and inorganic strontium/calcium phosphate(Sr/CaP)was fabricated on plasma-electrolytically oxidised magnesium via one-step cathodic electrodeposition.First,Sr-doped dicalcium phosphate dihydrate and hydroxyapatite(DCPD and HA)was deposited,followed by a collagen/CaP layer.The morphological evolution,sequential degradation behaviour,and in vitro bio-properties of the coatings were investigated.The incorporation of collagen remarkably refined the morphology of the CaP,and a more aggregated nano-spherical morphology was observed with increasing collagen concentration.Sr could partially replace Ca in the CaP crystals.Collagen combined with CaP formed a relatively stable skeletal frame,which provided sufficient barrier properties and more sites for the re-precipitation of bone tissue,as well as a more promising proliferation and differentiation ability of osteoblasts.A gradient coating that matches the requirements of bone growth at various periods is suggested for implantation. 展开更多
关键词 Biomedical magnesium alloys Gradient coating Sequential degradation Barrier property Bone formation BIOCOMPATIBILITY
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Yeast culture in weaned lamb feed:a proteomic journey into enhanced rumen health and growth
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作者 Xueqiang Li Xiaolin Yang +7 位作者 hui chen Shixiong Liu Puguo Hao Jie Ning Yingga Wu Xi Liang Yufei Zhang Dacheng Liu 《Journal of Animal Science and Biotechnology》 2025年第5期2389-2416,共28页
Background Using yeast culture as additives in ruminant feed prevents rumen microbial dysbiosis,enhances performance,and regulates rumen pH.The yeast culture used in this study was developed in-house,and has been show... Background Using yeast culture as additives in ruminant feed prevents rumen microbial dysbiosis,enhances performance,and regulates rumen pH.The yeast culture used in this study was developed in-house,and has been shown to promote rumen epithelial growth in several sheep trials.Changes in protein expression associated with the promotion of rumen epithelial development following the addition of yeast culture,along with the associated molecular mechanisms,remain unknown.We used 2045-day-old weaned lambs to investigate the specific proteins and molecular mechanisms involved in these processes.Half of the lambs were fed yeast culture,and the other half were used as controls.Results Yeast culture enhanced growth performance,facilitated rumen fermentation,and promoted rumen papilla development in weaned lambs.Proteomics data identified 4,831 proteins in the rumen epithelial tissue of lambs,comprising 87 upregulated and 425 downregulated proteins.Administration of yeast culture activated multiple molecular functions within rumen epithelial cells,including oxidative phosphorylation,glutathione metabolism,apoptosis,cell cycle,and vitamin digestion and absorption.The expression of proteins associated with cell cycle regulation increased,whereas those associated with apoptosis decreased.Administration of yeast culture also reduced the duration of the G0/G1 phase of rumen epithelial cells and accelerated the cell cycle.Furthermore,yeast culture showed increased cyclin D1,cyclin-dependent kinase(CDK)2,CDK4,CDK6,and cyclin E1 expressions and decreased cytochrome C(Cyto-c),Bcl-2-related X protein(Bax),cleaved caspase 3(C-caspase 3),caspase 3,and cleaved caspase 7(C-caspase 7)protein expressions.Yeast culture upregulated the insulin-like growth factor-1 receptor(IGF-1R)and insulin-like growth factor-binding protein 5(IGFBP-5)mRNA expressions in rumen epithelial cells.Conclusions Yeast culture facilitates rumen epithelial development by regulating the cell cycle and IGF-1 signaling and reducing the expression of proteins associated with apoptosis in rumen epithelial cells.The findings of this study provide novel insights into the molecular mechanisms through which yeast culture promotes rumen epithelial development in weaned lambs. 展开更多
关键词 Apoptosis Cell cycle PROTEOME Rumen epithelial Weaned lamb Yeast culture
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