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Detour for the inexperienced? Migration count data suggest mostly juvenile Greater Spotted Eagles appear in coastal peninsulas in China
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作者 Xu Shi xiaoping wang +2 位作者 Qian Wei Qiwei Lin Lei Zhu 《Avian Research》 SCIE CSCD 2024年第2期249-254,共6页
Soaring bird migration often relies on suitable terrain and airflow;therefore,route selection is vital for successful migration.While age and experience have been identified as key factor influencing migration route s... Soaring bird migration often relies on suitable terrain and airflow;therefore,route selection is vital for successful migration.While age and experience have been identified as key factor influencing migration route selection among soaring raptors in the African-Eurasian Flyway,how they shape the migration route of soaring raptors in East Asia is still largely unknown.In this study,we investigated potential variations in the routes and timing in autumn migration of juvenile and older soaring birds,using count data of Greater Spotted Eagles(Clanga clanga)from two coastal sites and two inland sites in China.From 2020 to 2023,we recorded a total of 340 individuals,with the highest site averaging over 90 individuals per autumn,making it one of the world’s top single-season counts and thus a globally important site for this species.We found that 82% and 61% records from coastal sites were juveniles,significantly higher than inland sites(15% and 24%).Juveniles at all four sites exhibited markedly earlier median passage time than non-juveniles,with brief overlapping in their main migration periods.Both coastal sites are located on the tip of peninsulas stretching southwest,requiring long overwater flights if crossing the Bohai Bay or Beibu Gulf,which would be energetically demanding and increase mortality risk.Experienced individuals may have learned to avoid such terrain and subsequent detour,while juveniles are more prone to enter these peninsulas due to lack of experience and opportunities for social learning,or following other raptor species that are more capable of powered flight.Our findings highlight the importance of age and experience in migration route selection of large soaring birds. 展开更多
关键词 Clanga clanga East Asia Greater Spotted Eagle JUVENILE Migration route Social learning
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Laser speckle contrast imaging to predict the effect of temporary spinal cord stimulation in postherpetic neuralgia patients: A prospective observational study
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作者 Xiang Huang Dacheng Tang +3 位作者 Pan Chen Lumiao Chen Xiaohong Li xiaoping wang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期69-75,共7页
Temporary spinal cord stimulation(tSCS)can effectively reduce the pain and severity of postherpetic neuralgia(PHN).However,there are no effective and objective methods for predicting the effects of tSCS on PHN.Laser s... Temporary spinal cord stimulation(tSCS)can effectively reduce the pain and severity of postherpetic neuralgia(PHN).However,there are no effective and objective methods for predicting the effects of tSCS on PHN.Laser speckle contrast imaging(LSCI)is frequently used in neurology to evaluate the effectiveness of treatment.To assess the accuracy of LSCI in predicting the impact of tSCS on PHN,14 adult patients receiving tSCS treatments for spinal nerve-innervated(C6-T2)PHN participated in this observational study.Visual analog scale(VAS)assessments and LSCI bloodflow images of the-ngers were recorded after the tSCS procedure.The results showed that the VAS scores of all patients decreased signi-cantly.Moreover,the bloodflow index(BFI)values were signi-cantly higher than they were before the procedure.Increased bloodflow and pain alleviation were positively correlated.The-ndings indicated that spinal nerve PHN(C6-T2)was signi-cantly reduced by tSCS.Pain alleviation by tSCS was positively correlated with increased bloodflow in the hand.The effect of tSCS on PHN may thus be predicted using an independent and consistent indicator such as LSCI. 展开更多
关键词 Laser speckle contrast imaging temporary spinal cord stimulation postherpetic neuralgia
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Integrating linear and nonlinear models to assess the built environment’s impact on older adults’behaviors in China
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作者 xiaoping wang Zeyan Li +2 位作者 Fang Wu Meng Zhang Hongyong Liu 《Chinese Journal of Population,Resources and Environment》 2024年第2期146-156,共11页
China is experiencing rapid population aging.The one contributing factor affecting senior citizens’lives is the disconnect between the built environment in urban and rural areas and the behavioral preferences of olde... China is experiencing rapid population aging.The one contributing factor affecting senior citizens’lives is the disconnect between the built environment in urban and rural areas and the behavioral preferences of older adults.However,research on the relation between the built environment and the behavior of older individuals has been limited.Thus,this paper uses the most recent health tracking data on factors influencing aging in China released in 2020(China Senior Health Survey Tracking Survey).Applying traditional regression,least absolute shrinkage and selection operator regression,and two decision tree optimization models from machine learning,a comprehensive comparative study is carried out to investigate the correlation between the built environment and the physical activity,dietary habits,and social interactions of older age groups.The findings reveal that built environment variables most significantly impact physical activity,accounting for 52.525%,followed by social interaction behaviors at 50.202%and dietary intake at 47.991%.Furthermore,the authors identify population density and greenness rate as the built environment factors having considerable effects on the behavior of older adults.Thus,this study establishes a theoretical foundation for developing age-friendly community environments for older adults. 展开更多
关键词 Built environment Behavioral activity AGING Machine learning
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本征型自愈合聚合物材料的研究进展 被引量:9
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作者 王小萍 程炳坤 +1 位作者 梁栋 贾德民 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第6期183-190,共8页
自愈合材料是一种具有自主修复机械损伤功能的特殊功能材料,最有研究前景的是具有完全自主型、无需外界刺激的本征型自愈合聚合物材料。这种材料实现自愈合的基础是分子链间存在着能够在温和条件下重复键合的、具有可逆性质的化学作用... 自愈合材料是一种具有自主修复机械损伤功能的特殊功能材料,最有研究前景的是具有完全自主型、无需外界刺激的本征型自愈合聚合物材料。这种材料实现自愈合的基础是分子链间存在着能够在温和条件下重复键合的、具有可逆性质的化学作用力。文中围绕多种可逆键在自愈合功能化聚合物中的应用研究,着重介绍了近年可逆共价键、氢键、离子键及其它可逆键型自愈合聚合物材料的发展现状,从材料的制备、机理与性能等方面进行了阐述,并对本征型自愈合聚合物的未来发展进行了展望。 展开更多
关键词 本征型 自愈合 聚合物 可逆键
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Clinical Application and Exploration on Steps Progressively Corrections and Gradual Shortening Combined with Total Spinal Osteotomy for Angular Kyphosis—Basic Research and Clinical Application
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作者 Ming Lu xiaoping wang +1 位作者 Dongyun Ren Huasong Ma 《Surgical Science》 2016年第1期39-47,共9页
Introduction: This study is designed to explore the biomechanical principles of posterior bilateral pedicle screw on steps progressively and tight closure on every step for severe angular kyphosis and the indication c... Introduction: This study is designed to explore the biomechanical principles of posterior bilateral pedicle screw on steps progressively and tight closure on every step for severe angular kyphosis and the indication conditions and clinical pathways of above new technique. Materials and Methods: A total of 90 patients have severe angular kyphosis, 37 males and 53 females, with an average age of 47 years. All patients were treated with posterior bilateral pedicle screw and step tight closure for gradual shortening and orthopedic technology. Results: Average intraoperative blood loss was 2089 ml. Average operation time was 326 minutes. Kyphotic angle changed from 90.1° averagely preoperatively to 41.6° averagely postoperatively with an improvement rate of 65%. The distance from C<sub>7</sub> plumb line to posterior upper edge of the S<sub>1</sub> vertebral body was averagely 5.2 mm postoperatively, with a correction rate of 73%. Neurological complications occurred in 2 cases, accounting for 6%. Non-neurological complications occurred in 2 cases, accounting for 6%. Anatomical parameters were significantly improved postoperatively (P < 0.05). All patients were averagely followed up for 28 months. Segments undergoing osteotomy achieved bone fusion, without loss of orthopedic angle. Conclusions: The orthopedic technology of bilateral pedicle screw and step tight closure designed by human physiology and biomechanical principles can protect spinal cord cells from injury to the utmost. To choose an appropriate osteotomy plane during pre-surgical planning can make the repair results closer to the normal function of the spine. Intraoperative nerve root protection, full release and bone graft fusion are effective safeguards to ensure kyphosis correction and to avoid spine lateral offset. 展开更多
关键词 Angular Kyphosis Total Spinal Osteotomy Biomechanical Analysis Clinical Outcome
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北京市生鲜农产品宅配优化对策探究
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作者 王晓平 闫飞 卢怀宇 《电子商务评论》 2017年第2期27-31,共5页
近年来随着电子商务的普及和快递业务的快速发展,北京市生鲜农产品宅配需求迅速增长,生鲜农产品宅配市场有很大发展空间。但是目前北京市生鲜农产品宅配不仅存在诸如宅配企业规模小、供应链不完善、信息技术不成熟等问题,还在需求群体... 近年来随着电子商务的普及和快递业务的快速发展,北京市生鲜农产品宅配需求迅速增长,生鲜农产品宅配市场有很大发展空间。但是目前北京市生鲜农产品宅配不仅存在诸如宅配企业规模小、供应链不完善、信息技术不成熟等问题,还在需求群体信任、空载问题,以及市场扩散等方面,面临挑战。本文将着重根据这三个问题,采用实地调研、问卷调查、查阅大量文献和会议资料的方法进行分析和研究,并结合北京市独特的环境分析,提出适合北京市生鲜农产品宅配的优化对策:建立宅配标准化、搭建共享宅配信息平台以及构建O2O生鲜智慧模式。 展开更多
关键词 生鲜农产品 宅配 优化对策
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哺乳动物滑翔和飞行性状适应性演化研究进展
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作者 高珊珊 李金良 +4 位作者 杨佳妮 周通 刘瑞 王晓萍 于黎 《遗传》 CAS CSCD 北大核心 2022年第1期46-58,共13页
运动形式的适应性演化与生物的捕食、防御、繁殖和通讯等生存行为紧密相关。哺乳动物演化出的多种多样的运动方式对占领新栖息地和获取新生存资源有着举足轻重的作用,其中滑翔和飞行能力是哺乳动物为适应环境而演化出的特殊运动形式,该... 运动形式的适应性演化与生物的捕食、防御、繁殖和通讯等生存行为紧密相关。哺乳动物演化出的多种多样的运动方式对占领新栖息地和获取新生存资源有着举足轻重的作用,其中滑翔和飞行能力是哺乳动物为适应环境而演化出的特殊运动形式,该类群动物已成为适应性演化研究的热点模型之一。为了适应生存,滑翔和飞行哺乳动物在形态、生理和行为方面都发生了一系列的适应性改变。近年来,随着基因组和转录组等高通量测序技术的日益发展,适应性演化研究进入了组学时代,能够更系统更全面地揭示适应性演化背后的分子基础。本文对哺乳动物滑翔和飞行能力的起源、适应性形态特征,包括翼膜和肢体演化,以及能量代谢等生理特征及其分子机制方面的研究进展进行了综述,以期为今后开展哺乳动物运动方式适应性演化的分子机制研究提供理论基础,同时对该类群研究所面临的挑战和未来的研究方向进行了展望。 展开更多
关键词 哺乳动物 飞行 滑翔 适应性演化 分子机制
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Clinical significance of main pancreatic duct dilation on computed tomography: Single and double duct dilation 被引量:9
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作者 Mark D Edge Maarouf Hoteit +3 位作者 Amil P Patel xiaoping wang Deborah A Baumgarten Qiang Cai 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第11期1701-1705,共5页
AIM: To study the patients with main pancreatic duct dilation on computed tomography (CT) and thereby to provide the predictive criteria to identify patients at high risk of significant diseases, such as pancreatic ca... AIM: To study the patients with main pancreatic duct dilation on computed tomography (CT) and thereby to provide the predictive criteria to identify patients at high risk of significant diseases, such as pancreatic cancer, and to avoid unnecessary work up for patients at low risk of such diseases. METHODS: Patients with dilation of the main pancreatic duct on CT at Emory University Hospital in 2002 were identified by computer search. Clinical course and ultimate diagnosis were obtained in all the identified patients by abstraction of their computer database records. RESULTS: Seventy-seven patients were identified in this study. Chronic pancreatitis and pancreatic cancer were the most common causes of the main pancreatic duct dilation on CT. Although the majority of patients with isolated dilation of the main pancreatic duct (single duct dilation) had chronic pancreatitis, one-third of patients with single duct dilation but without chronic pancreatitis had pancreatic malignancies, whereas most of patients with concomitant biliary duct dilation (double duct dilation) had pancreatic cancer. CONCLUSION: Patients with pancreatic double duct dilation need extensive work up and careful followup since a majority of these patients are ultimately diagnosed with pancreatic cancer. Patients with single duct dilation, especially such patients without any evidence of chronic pancreatitis, also need careful follow-up since the possibility of pancreatic malignancy, including adenocarcinoma and intraductal papillary mucinous tumors, is still high. 展开更多
关键词 Pancreatic duct Common bile duct Intrahepatic duct Chronic pancreatitis Pancreatic cancer
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Numerical analysis for viscoelastic fluid flow with distributed/variable order time fractional Maxwell constitutive models 被引量:5
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作者 Yanli QIAO xiaoping wang +1 位作者 Huanying XU Haitao QI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第12期1771-1786,共16页
Fractional calculus has been widely used to study the flow of viscoelastic fluids recently,and fractional differential equations have attracted a lot of attention.However,the research has shown that the fractional equ... Fractional calculus has been widely used to study the flow of viscoelastic fluids recently,and fractional differential equations have attracted a lot of attention.However,the research has shown that the fractional equation with constant order operators has certain limitations in characterizing some physical phenomena.In this paper,the viscoelastic fluid flow of generalized Maxwell fluids in an infinite straight pipe driven by a periodic pressure gradient is investigated systematically.Consider the complexity of the material structure and multi-scale effects in the viscoelastic fluid flow.The modified time fractional Maxwell models and the corresponding governing equations with distributed/variable order time fractional derivatives are proposed.Based on the L1-approximation formula of Caputo fractional derivatives,the implicit finite difference schemes for the distributed/variable order time fractional governing equations are presented,and the numerical solutions are derived.In order to test the correctness and availability of numerical schemes,two numerical examples are established to give the exact solutions.The comparisons between the numerical solutions and the exact solutions have been made,and their high consistency indicates that the present numerical methods are effective.Then,this paper analyzes the velocity distributions of the distributed/variable order fractional Maxwell governing equations under specific conditions,and discusses the effects of the weight coefficient(α)in distributed order time fractional derivatives,the orderα(r,t)in variable fractional order derivatives,the relaxation timeλ,and the frequencyωof the periodic pressure gradient on the fluid flow velocity.Finally,the flow rates of the distributed/variable order fractional Maxwell governing equations are also studied. 展开更多
关键词 distributed order time fractional derivative variable order time fractional derivative finite difference scheme viscoelastic fluid
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OsABA8ox2, an ABA catabolic gene, suppresses root elongation of rice seedlings and contributes to drought response 被引量:5
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作者 Yan Zhang xiaoping wang +6 位作者 Yanzhong Luo Lan Zhang Yuan Yao Lu Han Zhenhua Chen Lei wang Yubin Li 《The Crop Journal》 SCIE CAS CSCD 2020年第3期480-491,共12页
In rice, OsABA8ox encodes abscisic acid(ABA) 8′-hydroxylase, which catalyzes the committed step of ABA catabolism. The contribution of ABA catabolism in root development remains unclear. We investigated the role of O... In rice, OsABA8ox encodes abscisic acid(ABA) 8′-hydroxylase, which catalyzes the committed step of ABA catabolism. The contribution of ABA catabolism in root development remains unclear. We investigated the role of OsABA8ox2 in root growth and development and drought response. GUS staining results showed that OsABA8ox2 was expressed mainly in roots at seedling stage and was strongly expressed in the meristematic zone of the radicle. OsABA8ox2 expression in roots was markedly decreased after 0.5 h polyethylene glycol(PEG) treatment and increased after 0.5 h rehydration, implying that OsABA8ox2 is a drought-responsive gene.OsABA8ox2 knockout mediated by the CRISPR-Cas9 system increased drought-induced ABA and indole-3-acetic acid accumulation in roots, conferred increased ABA sensitivity, and promoted a more vertically oriented root system architecture(RSA) beneficial to drought tolerance.OsABA8ox2 overexpression suppressed root elongation and increased stomatal conductance and transpiration rate. Consequently, OsABA8ox2 knockout dramatically improved rice drought tolerance, whereas OsABA8ox2 overexpression seedlings were hypersensitive to drought stress,suggesting that OsABA8ox2 contributes to drought response in rice. Compared with wild type,functional leaves of OsABA8ox2 knockout seedlings showed higher ABA levels, whereas overexpression lines showed lower ABA levels, suggesting that OsABA8ox2, as an ABA catabolic gene, modulates ABA concentration through ABA catabolism. OsABA8ox2 and OsABA8ox3 were both localized in the endoplasmic reticulum. Together, these results indicate that OsABA8ox2 suppresses root elongation of rice seedlings, increases water transpiration, and contributes to drought response through ABA catabolism, and that OsABA8ox2 knockout dramatically improves rice drought tolerance. They highlight the key role of ABA catabolism mediated by OsABA8ox2 on root growth and development. OsABA8ox2, as a novel RSA gene, would be a potential genetic target for the improvement of rice drought tolerance. 展开更多
关键词 ABA suppresses root elongation of rice seedlings and contributes to drought response OsABA8ox2 an ABA catabolic gene
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Anterior limb lesions in bilateral internal capsules and memory function in patients with refractory obsessive-compulsive disorder 被引量:3
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作者 Yumei Jiang Bomin Sun +3 位作者 xiaoping wang Weifeng Zhang Xinfeng Zhao Lassonde MO 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第12期948-953,共6页
BACKGROUND: Previous studies have shown that lesions in the anterior limb of the internal capsule contribute to obsessive-compulsive symptoms in patients with refractory obsessive-compulsive disorder (OCD). However... BACKGROUND: Previous studies have shown that lesions in the anterior limb of the internal capsule contribute to obsessive-compulsive symptoms in patients with refractory obsessive-compulsive disorder (OCD). However, few reports have addressed the effects of lesions in the anterior limb of the internal capsule on cognition, learning, and memory functions in patients with refractory OCD. OBJECTIVE: To investigate the degree of damage to memory tasks in refractory OCD patients following lesions to the anterior limb of the internal capsule. DESIGN, TIME AND SETTING: A case-controlled, observational study was performed at the Department of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao-Tong University, China from May 2007 to March 2008. PARTICIPANTS: A total of 10 refractory OCD patients were admitted to the Department of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao-Tong University, China from May 2007 to March 2008 and were recruited for this study. The OCD patients were of equal gender, with an average age of (25.1 ± 9.6) years. An additional 10 healthy volunteers were enrolled from a community of Shanghai City as controls; they were of equal gender and aged (25.1 ± 8.6) years. METHODS: A total of 10 refractory OCD patients were subjected to lesions in the anterior limbs of the bilateral internal capsules. Wechsler Memory Scale-Chinese Revision (WMS-CR, as a task of explicit memory) and the Nissen Version (serial reaction time task) software (SRTT, as a task of implicit memory) were applied to determine memory functions and learning performance in pre- and post-operative OCD patients and controls. MAIN OUTCOME MEASURES: WMS scores, reaction time in SRTT, and Yale-Brown obsessive compulsive scale scores were measured in pre- and post-operative OCD patients and controls. RESULTS: Compared to controls, the pre-operative OCD patients exhibited reduced memory task scores (P = 0.005), whereas scores for reciting numbers of backwards digits were greater (P = 0.000). Figure recall and associative memory were less in OCD patients at 1 week following surgery than in the pre-operative OCD patients (P = 0.042, P = 0.002, respectively). Reaction time in implicit SRTT was significantly longer in pre-operative OCD patients compared with controls and post-operative OCD patients (P = 0.01, P = 0.03, respectively). These results suggested ameliorated SRTT following neurosurgery. Yale-Brown Obsessive Compulsive Scale results revealed significantly improved OCD following lesions in the internal capsule (P = 0.04). Some post-operative OCD patients suffered from deficits in short-term memory and implicit memory. CONCLUSION: Lesions in anterior limbs of bilateral internal capsules improve obsessive- compulsive symptoms and implicit memory in OCD patients, but result in aggravated short-term memory deficits. 展开更多
关键词 obsessive-compulsive disorder functional neurosurgery basal ganglia COGNITION implicit memory
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Effect of high-voltage discharge non-thermal plasma on g-C_3N_4 in a plasma-photocatalyst system 被引量:3
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作者 xiaoping wang Yixia Chen +2 位作者 Min Fu Zihan Chen Qiulin Huang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第10期1672-1682,共11页
The synergistic effect of high voltage discharge non‐thermal plasma(NTP)and photocatalysts on contaminant removal has repeatedly confirmed by plenty of researches.Most previous plasma‐photocatalyst synergistic syste... The synergistic effect of high voltage discharge non‐thermal plasma(NTP)and photocatalysts on contaminant removal has repeatedly confirmed by plenty of researches.Most previous plasma‐photocatalyst synergistic systems focused on the utilization of the ultraviolet light but ignored the visible light generated by high voltage discharge.Graphitic carbon nitride(g‐C3N4),a metal‐free semiconductor that exhibits high chemical stability,can utilize both the ultraviolet and visible light from high voltage discharge.However,the synergistic system of NTP and g‐C3N4 has been researched little.In this paper,the effect of NTP generated by dielectric barrier discharge(DBD)on g‐C3N4 is studied by comparing the photocatalytic activities,the surface physical structure and the surface chemical characteristics of pristine and plasma treated g‐C3N4.Experimental results indicate that the DBD plasma can change the physical structure and the chemical characteristics and to further affect the photocatalytic activity of g‐C3N4.The effect of NTP on g‐C3N4 is associated with the discharge intensity and the discharge time.For a long time scale,the effect of NTP on g‐C3N4 photocatalysts presents a periodic change trend. 展开更多
关键词 g‐C3N4 Non‐thermal plasma Photocatalytic activity Physical structure Chemical characteristic
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Robust H_∞ control for neutral stochastic uncertain systems with time-varying delay 被引量:3
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作者 Guici Chen xiaoping wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期658-665,共8页
The problem of robust H_∞ control for uncertain neutral stochastic systems with time-varying delay is discussed.The parameter uncertaintie is assumed to be time varying norm-bounded.First,the stochastic robust stabil... The problem of robust H_∞ control for uncertain neutral stochastic systems with time-varying delay is discussed.The parameter uncertaintie is assumed to be time varying norm-bounded.First,the stochastic robust stabilization of the stochastic system without disturbance input is investigated by nonlinear matrix inequality method.Then,a full-order stochastic dynamic output feedback controller is designed by solving a bilinear matrix inequality(BMI),which ensures a prescribed stochastic robust H_∞ performance level for the resulting closed-loop system with nonzero disturbance input and for all admissible uncertainties.An illustrative example is provided to show the feasibility of the controller and the potential of the proposed technique. 展开更多
关键词 stochastic robust H_∞ control neutral stochastic system uncertain system stochastic dynamic output feedback controller bilinear matrix inequality(BMI).
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Ultrastructure of focal cerebral cortex tissue from rats with focal cortical dysplasia 被引量:3
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作者 Xuntai Ma Yong Yan +5 位作者 Xuefeng wang Chunyang Luo xiaoping wang Ning Yan Xiangqin Liu Yan Li 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第12期705-708,共4页
BACKGROUND: Developing a model of focal cortical dysplasia in microgyrus and observing the ultrastructure of focal tissue is of important significance for analyzing the pathology of cortical developmental disorder an... BACKGROUND: Developing a model of focal cortical dysplasia in microgyrus and observing the ultrastructure of focal tissue is of important significance for analyzing the pathology of cortical developmental disorder and the factors of structural changes. OBJECTIVE: This study was to observe the pathological characteristics of focal tissue around the microgyrus of rats with cortical developmental disorder using an electron microscope, so as to analyze the causes associated with cerebral cortical developmental disorder. DESIGN: A randomized controlled animal experiment. SETTING: The First Affiliated Hospital of Chongqing Medical University. MATERIALS: This study was carried out in the Chongqing Key Laboratory of Neurology, Room for Electron Microscope of Chongqing Medical University, and Laboratory Animal Center, Research Institute of Surgery, Daping Hospital, Third Military Medical University of Chinese PLA between January 2004 and August 2006. Eighteen healthy newborn male Wistar rats, weighing 3.0 - 6.0 g, provided by the Laboratory Animal Center, Daping Hospital, Third Military Medical University of Chinese PLA, were involved in this study. The protocol was carried out in accordance with animal ethics guidelines for the use and care of animals. Probes (Chongqing Wire & Cable Factory, China) were made of copper core wire with diameter of 1mm. METHODS: The rats were randomly divided into 3 groups with 6 in each: normal control group, liquid nitrogen injured group and sham-operation group. (1)In the liquid nitrogen injured group, a blunt probe frozen by liquid nitrogen was placed on fronto-parietal crinial bone of rats for 8 s. A 3 - 5 cm of microgyrus was induced in the unilateral cerebral sensory cortical area. In the sham-operation group, probe was placed at the room temperature. In the normal control group, rats were untouched. (2) The conscious state and electrical activity of brain of rats in each group were observed. (3) 2 - 3 mm thickness of hippocampal tissue with coronary section was taken for observing its ultrastructure under a transmission electron microscope. MAIN OUTCOME MEASURES: (1) The ultrastructure of hippocampal tissue. (2)The conscious state and electrical activity of brain of rats. RESULTS: Eighteen rats were enrolled in the final analysis. (1) Observation of hippocampal ultrastructure: Electromicroscopic pathological findings showed that for each rat of the liquid nitrogen injured group, mitochondrium in the pyramidal neuron around the microgyrus was swelled, endoplasmic reticulum was expanded, glial cells were swelled, water gathered around the blood capillary, partial medullary sheath was degenerated, neuropilem was normal and no obviously abnormal synapse was found. (2) Changes in conscious state of rats: Rats in the normal control group and sham-operation group had no convulsive seizure, but those in the liquid nitrogen injured group had occasionally. Most of them showed increased activities, excitation and restlessness, scratching and frequent " watching face-like activities". (3)Electrical activity of brain of rats: Electroencephalogram recording of liquid nitrogen injured group showed that small wave amplitude of rhythm took the main part. No typical sharp wave, V wave, sharp and slow wave, V and slow waves were discharged. CONCLUSION: Liquid nitrogen can lead to cerebral cortical developmental disorder. Pathological changes of ultrastructure of focal tissue around the microgyrus can provide pathological basis for epilepsy associated with focal cortical developmental disorder. 展开更多
关键词 cortical developmental disorder focal electromicroscopic pathology RATS
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Expression of netrin-1 and its receptors, deleted in colorectal cancer and uncoordinated locomotion-5 homolog B, in rat brain following focal cerebral ischemia reperfusion injury 被引量:1
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作者 Xiaodan wang Jinming Xu +2 位作者 Jieqin Gong Hui Shen xiaoping wang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第1期64-69,共6页
Netrin-1 is currently one of the most highly studied axon guidance factors. Netrin-1 is widely expressed in the embryonic central nervous system, and together with the deleted in colorectal cancer and uncoordinated lo... Netrin-1 is currently one of the most highly studied axon guidance factors. Netrin-1 is widely expressed in the embryonic central nervous system, and together with the deleted in colorectal cancer and uncoordinated locomotion-5 homolog B receptors, netrin-1 plays a guiding role in the construction of neural conduction pathways and the directional migration of neuronal cells. In this study, we established a rat middle cerebral artery ischemia reperfusion model using the intraluminal thread technique. Immunofluorescence microscopy showed that the expression of netrin-1 and deleted in colorectal cancer in the ischemic penumbra was upregulated at 1 day after reperfusion, reached a peak at 14 days, and decreased at 21 days. There was no obvious change in the expression of uncoordinated locomotion-5 homolog B during this time period. Double immunofluorescence labeling revealed that netrin-1 was expressed in neuronal cells and around small vessels, but not in astrocytes and microglia, while deleted in colorectal cancer was localized in the cell membranes and protrusions of neurons and astrocytes. Our experimental findings indicate that netrin-1 may be involved in post-ischemic repair and neuronal protection via deleted in colorectal cancer receptors. 展开更多
关键词 neural regeneration brain injury cerebral ischemia and reperfusion NETRIN-1 uncoordinatedlocomotion-5 homolog B deleted in colorectal cancer neuron brain injury grant-supported paper photographs-containing paper NEUROREGENERATION
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“新农科”背景下农林卓越班有机化学(英文)课程内涵新体系的构建和实践 被引量:3
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作者 汤江江 袁茂森 +2 位作者 王凤 王小平 王俊儒 《大学化学》 CAS 2022年第8期179-184,共6页
面对“新农科”背景下农林卓越一流人才培养挑战,课程组在全英文有机化学教学前期实践基础上,稳步推进理念更新、环节精细设计、内容模块优化、优质资源支撑和综合考核等教学实践,实现了新教学策略下融入反馈优化机制的新型体系构建,支... 面对“新农科”背景下农林卓越一流人才培养挑战,课程组在全英文有机化学教学前期实践基础上,稳步推进理念更新、环节精细设计、内容模块优化、优质资源支撑和综合考核等教学实践,实现了新教学策略下融入反馈优化机制的新型体系构建,支撑课程内涵提升,并从帮助学生建立学术宽视野主动吸收分子科技营养、提升教师的认知理论意识和能力运用、构建课程三维图谱助个性化发展等3个方面提出课程创新展望。 展开更多
关键词 新农科 有机化学 学科交叉 课程内涵 英文教学
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Interaction between Bax and Bcl-XL proteins confirmed by partial acceptor photobleaching-based FRET imaging 被引量:1
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作者 Fangfang Yang Mengyan Du +1 位作者 xiaoping wang Tongsheng Chen 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2020年第3期81-91,共11页
Exact interaction mechanism between Bax and Bcl-XL,two key Bcl-2 family proteins,is an interesting and controversial issue.Partial acceptor photobleaching-based quantitative fluores-cence resonance energy transfer(FRE... Exact interaction mechanism between Bax and Bcl-XL,two key Bcl-2 family proteins,is an interesting and controversial issue.Partial acceptor photobleaching-based quantitative fluores-cence resonance energy transfer(FRET)measurement,PbFRET,is a widely used FRET quantification method in living cells.In this report,we implemented pixel-to-pixel PbFRET imaging on a wide-field microscope to map the FRET efficiency(E)images of single living HepG2 cells co-expressing CFP-Bax and YFP-Bcl-XL.The E value between CFP-Bax and YFP-Bcl-XL was 4.59%in cytosol and 11.31%on mitochondria,conclusively indicating the direct interaction of the two proteins,and the interaction of the two proteins was strong on mitochondria and modest in cytosol. 展开更多
关键词 BAX BCL-XL protein-protein interaction FRET imaging living cells
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Feasibility study of miniature near-infrared spectrometer for the measurement of solar irradiance within Arctic snow-cover sea ice 被引量:1
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作者 Liwen Nan xiaoping wang +2 位作者 Hangzhou wang Hongliang Zhou Ying Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第9期115-124,共10页
The extremely low temperature,high humidity and limited power supply pose considerable challenges when using spectrometers within the Arctic sea ice.The feasibility of using a miniature low-power near-infrared spectro... The extremely low temperature,high humidity and limited power supply pose considerable challenges when using spectrometers within the Arctic sea ice.The feasibility of using a miniature low-power near-infrared spectrometer module to measure solar radiation in Arctic sea ice environments was investigated in this study.Temperature and integration time dependences of the spectrometer module were examined over the entire target operating range of–50°C to 30°C,well below the specified operating range of this spectrometer.Using these observations,a dark output prediction model was developed to represent dark output as a function of temperature and integration time.Temperature-induced biases in the saturation output and linear operating range of the spectrometer were also determined.Temperature and integration time dependences of the signal output were evaluated.Two signal output correction models were developed and compared,to convert the signal output at any temperature within the operating temperature range and integration time to that measured at the reference temperature and integration time.The overall performance of the spectrometer was evaluated by integrating it into a refined fiber optic spectrometry system and measuring solar irradiance distribution in the ice cover with thickness of 1.85 m in the Arctic during the 9th Chinese National Arctic Research Expedition.The general shape of the measured solar irradiance above the snow surface agreed well with that measured by other commercial oceanographic spectroradiometers.The measured optical properties of the sea ice were generally comparable to those of similar ice measured using other instruments.This approach provides a general framework for assessing the feasibility of using spectrometers for applications in cold environments. 展开更多
关键词 near-infrared spectrometer LOW-TEMPERATURE Arctic sea ice
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Polyoxymethylene dimethyl ethers synthesis from methanol and formaldehyde solution over one-pot synthesized spherical mesoporous sulfated zirconia
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作者 Xiangjun Li Shujun Li +2 位作者 xiaoping wang Muhammad Asif Nawaz Dianhua Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第6期161-172,共12页
The synthesis of polyoxymethylene dimethyl ethers as an ideal diesel fuel additive is the current hot topic of modern petrochemical industry for their expedient properties in mitigating air pollutants emission during ... The synthesis of polyoxymethylene dimethyl ethers as an ideal diesel fuel additive is the current hot topic of modern petrochemical industry for their expedient properties in mitigating air pollutants emission during combustion.In this work,a series of spherical sulfated zirconia catalysts were prepared by a one-pot hydrothermal method assisted with surfactant cetyltrimethylammonium bromide(CTAB).The prepared sulfated zirconia catalysts were used to catalyze PODEn synthesis from methanol and formaldehyde solution.Various characterization(XRD,BET,SEM,TGA,NH_(3)-TPD,FTIR,and Py-IR)were employed to elaborate the structure–activity relationship of the studied catalytic system.The results demonstrated that S/Zr molar ratio in precursor solution played an effective role on catalyst morphology and acidic properties,where the weak Brønsted acid sites and strong Lewis acid sites were favorable to the conversion of methanol and formation of long-chain PODEn,respectively.The reaction parameters such as catalyst amount,molar ratio of FA/MeOH,reaction time,temperature and pressure were optimized.The speculated reaction pathway for PODEn synthesis was proposed based on the synergy of Brønsted and Lewis acid sites,which suggested that Brønsted and Lewis acid sites might be advantageous to the activation of polyoxymethylene hemiformals[CH_(3)(OCH_(2))_(n)OH]and methylene glycol(HOCH_(2)OH),respectively. 展开更多
关键词 Polyoxymethylene dimethyl ethers Spherical sulfated zirconia METHANOL FORMALDEHYDE Reaction pathway Synergistic effect
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High-Throughput Powder Diffraction Using White X-Ray Beam and a Simulated Energy-Dispersive Array Detector
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作者 xiaoping wang Weiwei Dong +6 位作者 Peng Zhang Haoqi Tang Lanting Zhang Tieying Yang Peng Liu Hong wang X.-D.Xiang 《Engineering》 SCIE EI 2022年第3期81-88,共8页
High-throughput powder X-ray diffraction(XRD)with white X-ray beam and an energy-dispersive detector array is demonstrated in this work on a CeO;powder sample on a bending magnet synchrotron beamline at the Shanghai S... High-throughput powder X-ray diffraction(XRD)with white X-ray beam and an energy-dispersive detector array is demonstrated in this work on a CeO;powder sample on a bending magnet synchrotron beamline at the Shanghai Synchrotron Radiation Facility(SSRF),using a simulated energy-dispersive array detector consisting of a spatially scanning silicon-drift detector(SDD).Careful analysis and corrections are applied to account for various experimental hardware-related and diffraction angle-related factors.The resulting diffraction patterns show that the relative strength between different diffraction peaks from energy-dispersive XRD(EDXRD)spectra is consistent with that from angle-resolved XRD(ARXRD),which is necessary for analyzing crystal structures for unknown samples.The X-ray fluorescence(XRF)signal is collected simultaneously.XRF counts from all pixels are integrated directly by energy,while the diffraction spectra are integrated by d-spacing,resulting in a much improved peak strength and signal-to-noise(S/N)ratio for the array detector.In comparison with ARXRD,the diffraction signal generated by a white X-ray beam over monochromic light under the experimental conditions is about 104 times higher.The full width at half maximum(FWHM)of the peaks in q-space is found to be dependent on the energy resolution of the detector,the angle span of the detector,and the diffraction angle.It is possible for EDXRD to achieve the same or even smaller FWHM as ARXRD under the energy resolution of the current detector if the experimental parameters are properly chosen. 展开更多
关键词 High-throughput experiment White beam X-ray diffraction Energy-dispersive array detector Energy-dispersive X-ray diffraction Angle-resolved X-ray diffraction
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