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Dysfunction of synaptic endocytic trafficking in Parkinson's disease 被引量:1
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作者 Xin Yi Ng Mian Cao 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2649-2660,共12页
Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the striatum.The precise reasons behind the specific degeneration of t... Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the striatum.The precise reasons behind the specific degeneration of these dopamine neurons remain largely elusive.Genetic investigations have identified over 20 causative PARK genes and 90 genomic risk loci associated with both familial and sporadic Parkinson's disease.Notably,several of these genes are linked to the synaptic vesicle recycling process,particularly the clathrinmediated endocytosis pathway.This suggests that impaired synaptic vesicle recycling might represent an early feature of Parkinson's disease,followed by axonal degeneration and the eventual loss of dopamine cell bodies in the midbrain via a"dying back"mechanism.Recently,several new animal and cellular models with Parkinson's disease-linked mutations affecting the endocytic pathway have been created and extensively characterized.These models faithfully recapitulate certain Parkinson's disease-like features at the animal,circuit,and cellular levels,and exhibit defects in synaptic membrane trafficking,further supporting the findings from human genetics and clinical studies.In this review,we will first summarize the cellular and molecular findings from the models of two Parkinson's disease-linked clathrin uncoating proteins:auxilin(DNAJC6/PARK19)and synaptojanin 1(SYNJ1/PARK20).The mouse models carrying these two PARK gene mutations phenocopy each other with specific dopamine terminal pathology and display a potent synergistic effect.Subsequently,we will delve into the involvement of several clathrin-mediated endocytosis-related proteins(GAK,endophilin A1,SAC2/INPP5 F,synaptotagmin-11),identified as Parkinson's disease risk factors through genome-wide association studies,in Parkinson's disease pathogenesis.We will also explore the direct or indirect roles of some common Parkinson's disease-linked proteins(alpha-synuclein(PARK1/4),Parkin(PARK2),and LRRK2(PARK8))in synaptic endocytic trafficking.Additionally,we will discuss the emerging novel functions of these endocytic proteins in downstream membrane traffic pathways,particularly autophagy.Given that synaptic dysfunction is considered as an early event in Parkinson's disease,a deeper understanding of the cellular mechanisms underlying synaptic vesicle endocytic trafficking may unveil novel to rgets for early diagnosis and the development of interventional therapies for Parkinson's disease.Future research should aim to elucidate why generalized synaptic endocytic dysfunction leads to the selective degeneration of nigrostriatal dopamine neurons in Parkinson's disease. 展开更多
关键词 AUTOPHAGY auxilin/park19 clathrin-mediated endocytosis dopamine neurons NEURODEGENERATION nigrostriatal pathway parkinson's disease synaptic vesicle recycling synaptojanin1/park20
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Smart Parking Management System “MOTAH”
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作者 Iman Alansari Ghadah Alnamlah +2 位作者 Razan Abduallah Jumana Alluqmani Alaa Alzahrani 《Journal of Software Engineering and Applications》 2024年第6期541-552,共12页
With a surge in the university’s student and staff population, parking problems and congestion have rapidly intensified. The recent inclusion of women drivers, particularly during official working hours, has exacerba... With a surge in the university’s student and staff population, parking problems and congestion have rapidly intensified. The recent inclusion of women drivers, particularly during official working hours, has exacerbated these challenges. This pressing issue underscores the critical necessity for a structured approach to managing university entries and overseeing parking at the gates. The proposed smart parking management system aims to address these concerns by introducing a design concept that restricts unauthorized access and provides exclusive parking privileges to authorized users. Through image processing, the system identifies available parking spaces, relaying real-time information to users via a mobile application. This comprehensive solution also generates detailed reports (daily, weekly, and monthly), aiding university safety authorities in future gate management decisions. 展开更多
关键词 Car parking Traffic Density Estimation Intelligent Transportation CONGESTION CONTROL parking Arrangement parking Behavior
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Path Planning and Tracking Control for Parking via Soft Actor-Critic Under Non-Ideal Scenarios 被引量:1
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作者 Xiaolin Tang Yuyou Yang +3 位作者 Teng Liu Xianke Lin Kai Yang Shen Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期181-195,共15页
Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adja... Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adjacent parking lots, which poses a safety threat to vehicles parked in these parking lots. However, previous studies have not addressed this issue. In this paper, we aim to evaluate the impact of parking deviation of existing vehicles next to the target parking lot(PDEVNTPL) on the automatic ego vehicle(AEV) parking, in terms of safety, comfort, accuracy, and efficiency of parking. A segmented parking training framework(SPTF) based on soft actor-critic(SAC) is proposed to improve parking performance. In the proposed method, the SAC algorithm incorporates strategy entropy into the objective function, to enable the AEV to learn parking strategies based on a more comprehensive understanding of the environment. Additionally, the SPTF simplifies complex parking tasks to maintain the high performance of deep reinforcement learning(DRL). The experimental results reveal that the PDEVNTPL has a detrimental influence on the AEV parking in terms of safety, accuracy, and comfort, leading to reductions of more than 27%, 54%, and 26%respectively. However, the SAC-based SPTF effectively mitigates this impact, resulting in a considerable increase in the parking success rate from 71% to 93%. Furthermore, the heading angle deviation is significantly reduced from 2.25 degrees to 0.43degrees. 展开更多
关键词 Automatic parking control strategy parking deviation(APS) soft actor-critic(SAC)
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Practical Experience of Management of Urban Parks at Home and Abroad
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作者 Wenqian LING Yong ZHU Qinhuai XU 《Meteorological and Environmental Research》 2024年第1期30-37,共8页
By systematically reviewing the practical experience of management of urban parks at home and abroad,the advanced experience in organization,management system,operation mechanism and social participation were summariz... By systematically reviewing the practical experience of management of urban parks at home and abroad,the advanced experience in organization,management system,operation mechanism and social participation were summarized,and the optimization and improvement measures for the construction and management of urban parks in Chengdu were proposed to provide reference for the high-level construction,high-quality experience and efficient management of urban parks in the construction of park city demonstration zone in Chengdu. 展开更多
关键词 Urban parks Management and operation Domestic and foreign experience Chengdu park city
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PARK2介导的帕金森病中帕金蛋白对α-突触核蛋白的作用 被引量:2
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作者 肖琪 樊慧杰 +8 位作者 李艳荣 范丽珊 和璐璐 谢良骐 贾璐 王青 肖保国 马存根 柴智 《中国老年学杂志》 CAS 北大核心 2024年第4期999-1005,共7页
帕金森病(PD)是常见的神经退行性疾病之一,主要表现为运动障碍,伴有主要运动症状,如运动迟缓、僵直性和静息性震颤,还可能表现为多种非运动症状,如自主神经功能障碍、认知障碍、睡眠障碍和神经精神症状〔1〕。
关键词 帕金森病 帕金蛋白 Α-突触核蛋白 park2基因突变
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高分辨MRI在肛瘘诊断及Parks分型中的应用价值
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作者 罗项超 周永进 +3 位作者 程淑芳 应海峰 陈玲 王祖飞 《医学影像学杂志》 2024年第4期159-161,共3页
目的 探讨高分辨MRI在肛瘘诊断及Parks分型中的应用价值。方法 选取肛瘘接受手术治疗患者108例,均行MRI检查,以手术结果为金标准,分析患者MRI特征及Parks分型。结果 108例中总计检出内口112个、瘘管124个、外口112个、肛周脓肿35个,与... 目的 探讨高分辨MRI在肛瘘诊断及Parks分型中的应用价值。方法 选取肛瘘接受手术治疗患者108例,均行MRI检查,以手术结果为金标准,分析患者MRI特征及Parks分型。结果 108例中总计检出内口112个、瘘管124个、外口112个、肛周脓肿35个,与手术确诊结果对比差异无统计学意义(P>0.05),其中括约肌间型64例、经括约肌型30例、括约肌上型11例、括约肌外型3例,与手术确诊结果对比差异无统计学意义(P>0.05)。结论 MRI应用于肛瘘诊断并进行Parks分型,能清晰显示出内口、外口、瘘管、脓肿位置以及数目信息。 展开更多
关键词 肛瘘 parks分型 磁共振成像
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PARK7基因对氧化应激的调控研究进展
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作者 樊庆灿 王倩倩 +2 位作者 杨虎 郑路程 胡威 《中国畜牧杂志》 CAS CSCD 北大核心 2024年第5期8-12,共5页
在规模化养殖模式下,畜禽在生长过程中会不可避免地面对各种不利因素,导致体内产生氧化应激,严重影响其生长发育。畜禽体内存在多种抗氧化因子来应对氧化应激。其中,帕金森相关蛋白7(Parkinson’s Disease-Associated Protein 7,PARK7)... 在规模化养殖模式下,畜禽在生长过程中会不可避免地面对各种不利因素,导致体内产生氧化应激,严重影响其生长发育。畜禽体内存在多种抗氧化因子来应对氧化应激。其中,帕金森相关蛋白7(Parkinson’s Disease-Associated Protein 7,PARK7)基因是细胞氧化应激中重要的调控因子之一。PARK7通过自身半胱氨酸的氧化水平感受氧化应激信号,并通过Nrf2、ERK1/2和PI3K/Akt等途径促进抗氧化酶的生成,提高细胞的抗氧化能力,从而减轻氧化应激引起的损伤。本文对PARK7基因在氧化应激中的调控作用和通路进行综述,将有助于畜禽氧化应激的调节机制研究。 展开更多
关键词 park7 DJ-1 氧化应激 Nrf2通路
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PARK9基因rs207663位点突变与早期帕金森病认知改善治疗应答相关性
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作者 王俊英 王静 +1 位作者 李亚萍 张永志 《中华老年心脑血管病杂志》 CAS 北大核心 2024年第6期670-673,共4页
目的探讨PARK9基因rs207663位点突变与早期帕金森病认知改善治疗应答相关性。方法选取2020年10月至2023年10月于邯郸市第四医院神经内科接受治疗的100例早期帕金森病患者为研究组,以100例健康体检者为对照组。检测PARK9基因rs207663位... 目的探讨PARK9基因rs207663位点突变与早期帕金森病认知改善治疗应答相关性。方法选取2020年10月至2023年10月于邯郸市第四医院神经内科接受治疗的100例早期帕金森病患者为研究组,以100例健康体检者为对照组。检测PARK9基因rs207663位点基因多态性,比较2组等位基因、基因型分布,以及分析不同基因型患者经治疗后的疗效情况。结果PARK9基因rs207663位点存在3种基因型:GG、GA、AA,研究组GG基因型、G等位基因频率高于对照组(40.0%vs 26.0%,P<0.05;63.0%vs 50.0%,P<0.01)。治疗后,3种基因型简易智能状态检查量表(MMSE)、蒙特利尔认知评估量表(MoCA)评分均呈增加趋势,其中GG基因型MMSE评分低于GA基因型[(22.95±1.34)分vs(23.89±1.68)分,P<0.05],GG基因型MoCA评分低于GA基因型[(24.86±1.83)分vs(25.12±1.48)分,P<0.05]。GA基因型总资产、安全选项次数、负反馈利用率均高于GG基因型[(-1541.50±537.24)元vs(-3102.00±1274.38)元,P<0.01;(9.24±3.27)次vs(7.11±2.14)次,P<0.05;(0.51±0.23)vs(0.35±0.15),P<0.05];AA基因型风险选项次数低于GA基因型,GA基因型风险选项次数低于GG基因型,差异有统计学意义(P<0.05)。结论PARK9基因rs207663位点多态性与早期帕金森病认知改善治疗应答存在显著相关性,其中GG基因型患者治疗应答较差,GG基因型患者偏爱高风险和高回报选项,负反馈利用率较低。 展开更多
关键词 帕金森病 认知 数据相关性 park9基因 rs207663位点突变
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Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China 被引量:1
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作者 HAN Nianlong YU Miao +2 位作者 JIA Peihong ZHANG Yucheng HU Ke 《Chinese Geographical Science》 SCIE CSCD 2024年第3期519-532,共14页
Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding s... Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the region.Based on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)model.System dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their relationships.The results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the two.Second,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural factors.The simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)scenarios.To maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened. 展开更多
关键词 human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National park(HTRNP)of China
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改良Park法重睑术治疗上睑松弛的疗效观察
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作者 许杰 张建文 《中国医疗美容》 2024年第7期37-40,共4页
目的探讨改良Park法重睑术治疗上睑松弛的临床疗效。方法以2023年1月至2023年12月在郑州缔莱美医疗美容医院就诊的31例上睑松弛患者为研究对象,所有患者均行改良Park法重睑术治疗,分析手术效果和手术并发症发生情况。结果31例患者中手... 目的探讨改良Park法重睑术治疗上睑松弛的临床疗效。方法以2023年1月至2023年12月在郑州缔莱美医疗美容医院就诊的31例上睑松弛患者为研究对象,所有患者均行改良Park法重睑术治疗,分析手术效果和手术并发症发生情况。结果31例患者中手术效果为完全改善18例,明显改善12例,有改善1例,无效0例,明显改善率为96.77%。术后感染2例(6.45%)、血瘀3例(9.68%)、重睑皱褶过窄2例(6.45%)、重睑线不对称1例(3.23%)。结论改良Park法重睑术治疗上睑松弛临床疗效较好,且不会造成严重的术后并发症,其临床应用价值较高。 展开更多
关键词 上睑松弛 改良park法重睑术 手术效果 并发症
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内眦开大术联合改良Park法重睑成形术在双侧单睑伴内眦赘皮患者中的应用效果观察 被引量:1
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作者 杜兴隆 张远其 《中国医疗美容》 2024年第2期11-15,共5页
目的观察内眦开大术联合改良Park法重睑成形术在双侧单睑伴内眦赘皮患者中的应用效果。方法选取82例于2020年9月至2023年9月在贵州医科大学附属乌当医院就诊的有求美需求的双侧单睑伴内眦赘皮患者,均为女性,按照治疗方式不同分为研究组... 目的观察内眦开大术联合改良Park法重睑成形术在双侧单睑伴内眦赘皮患者中的应用效果。方法选取82例于2020年9月至2023年9月在贵州医科大学附属乌当医院就诊的有求美需求的双侧单睑伴内眦赘皮患者,均为女性,按照治疗方式不同分为研究组和对照组,各41例(82只眼)。对照组采取内眦开大术联合传统Park重睑成形术,研究组采取内眦开大术联合改良Park法重睑成形术。比较两组患者术中出血量、瘢痕消失时间、术后满意度和临床疗效。结果研究组术中出血量少于对照组,手术时间短于对照组,瘢痕消失时间早于对照组,术后总满意度高于对照组患者,术后7天眼睑宽度小于对照组,眼裂高度大于对照组,术后半年上睑提肌肌力大于对照组,临床疗效总有效率高于对照组,并发症总发生率小于对照组,差异有统计学意义(P均<0.05)。结论内眦开大术联合改良Park法重睑成形术用于治疗双侧单睑伴内眦赘皮临床疗效较好,术中出血量少,术后并发症少,瘢痕消失时间早,恢复速度快,重睑形态对称自然,患者满意度高,值得临床应用。 展开更多
关键词 改良park 重睑成形术 内眦开大术 单睑 内眦赘皮
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改良Park法重睑术与传统切开法重睑术治疗上睑松弛伴臃肿患者的效果对比 被引量:1
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作者 史迅 周彦鹏 李九旭 《临床医学工程》 2024年第4期431-432,共2页
目的探讨改良Park法重睑术与传统切开法重睑术治疗上睑松弛伴臃肿患者的效果。方法45例上睑松弛伴臃肿患者按治疗方法的不同分为对照组(传统切开法重睑术)和观察组(改良Park法重睑术),比较两组的手术情况、眼睑形态、修复满意度及并发... 目的探讨改良Park法重睑术与传统切开法重睑术治疗上睑松弛伴臃肿患者的效果。方法45例上睑松弛伴臃肿患者按治疗方法的不同分为对照组(传统切开法重睑术)和观察组(改良Park法重睑术),比较两组的手术情况、眼睑形态、修复满意度及并发症。结果观察组的手术时间、拆线时间及术后恢复时间均短于对照组,术后3个月的眼睑形态评分及修复满意度评分均高于对照组(P<0.05)。两组的并发症总发生率相比,差异无统计学意义(P>0.05)。结论与传统切开法重睑术相比,改良Park法重睑术治疗上睑松弛伴臃肿的效果更显著,安全性更高,可改善患者眼睑形态,提高修复满意度。 展开更多
关键词 上睑松弛 臃肿 改良park法重睑术 眼睑形态
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显微镜下改良Parks切口斜视矫正术治疗水平共同性斜视患儿的效果及其对泪膜功能的影响
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作者 高锦展 王素萍 何利 《实用防盲技术》 2024年第1期41-43,F0003,共4页
目的探探讨显微镜下改良Parks切口斜视矫正术治疗水平共同性斜视患儿的效果及其对泪膜功能的影响。方法选取我科2017年6月至2019年11月期间95例水平共同性斜视患儿作为研究对象,按照随机数字表法分成两组,均行斜视矫正术,对照组47例给... 目的探探讨显微镜下改良Parks切口斜视矫正术治疗水平共同性斜视患儿的效果及其对泪膜功能的影响。方法选取我科2017年6月至2019年11月期间95例水平共同性斜视患儿作为研究对象,按照随机数字表法分成两组,均行斜视矫正术,对照组47例给予术中作角膜缘梯形结膜瓣切口,观察组48例给予显微镜下改良Parks切口,1个月后对比两组患儿视功能改善效果、手术效果、泪膜功能。结果观察组治疗后总有效率95.83%高于对照组89.36%(χ^(2)=0.6632,P=0.4154);观察组水平共同性斜视患儿手术时间明显短于对照组(t=11.9892,P=0.0000);观察组患儿治疗后泪液分泌量高于对照组(t=15.0051,P=0.0000),泪膜破裂时间较对照组上升(t=9.2228,P=0.0000),角膜荧光染色评分较对照组降低(t=10.7815,P=0.0000)。结论显微镜下改良Parks切口斜视矫正术治疗水平共同性斜视效果确切,能够显著矫正眼部,改善患儿视功能及泪膜功能,安全可靠,值得应用。 展开更多
关键词 微镜下改良parks切口斜视矫正术 水平共同性斜视 泪膜功能
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改良Park法重睑成形术与传统切开重睑术用于单睑伴内眦赘皮的疗效和安全性对比研究
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作者 黄积荣 李守春 +2 位作者 赵丽丽 陈树 洪丽容 《大医生》 2024年第7期39-41,共3页
目的探讨改良Park法重睑成形术与传统切开重睑术用于单睑伴内眦赘皮的疗效和安全性,为临床提供参考。方法选取2021年11月至2023年1月贵港市人民医院收治的80例行重睑成形术的单睑伴内眦赘皮患者,按照随机数字表法分为对照组与观察组,各4... 目的探讨改良Park法重睑成形术与传统切开重睑术用于单睑伴内眦赘皮的疗效和安全性,为临床提供参考。方法选取2021年11月至2023年1月贵港市人民医院收治的80例行重睑成形术的单睑伴内眦赘皮患者,按照随机数字表法分为对照组与观察组,各40例。给予对照组患者传统切开重睑术进行治疗,给予观察组患者改良Park法重睑成形术进行治疗。比较两组患者临床效果、手术相关指标、温哥华瘢痕评分量表(VSS)评分和并发症发生情况。结果观察组患者整体疗效优于对照组,总有效率较对照组更高(均P<0.05)。观察组患者手术时间、拆线时间和术后恢复时间比对照组更短,术中出血量比对照组更少(均P<0.05)。两组VSS评分具有时间、组间、交互效应差异;两组术后6个月低于术后3个月和术后1个月,术后3个月低于术后1个月,且观察组低于对照组(P<0.05)。观察组患者并发症总发生率比对照组更低(P<0.05)。结论与传统切开重睑术比较,改良Park法重睑成形术治疗单睑伴内眦赘皮效果更好,同时手术时间、拆线时间和术后恢复时间均更短,术中出血量更少,同时可改善患者术后的瘢痕情况,安全性好。 展开更多
关键词 改良park法重睑成形术 传统切开重睑术 单睑伴内眦赘皮 安全性
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Terrain or climate factor dominates vegetation resilience?Evidence from three national parks across different climatic zones in China
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作者 Shuang Liu Lingxin Wu +3 位作者 Shiyong Zhen Qinxian Lin Xisheng Hu Jian Li 《Forest Ecosystems》 SCIE CSCD 2024年第4期526-542,共17页
Vegetation resilience(VR),providing an objective measure of ecosystem health,has received considerable attention,however,there is still limited understanding of whether the dominant factors differ across different cli... Vegetation resilience(VR),providing an objective measure of ecosystem health,has received considerable attention,however,there is still limited understanding of whether the dominant factors differ across different climate zones.We took the three national parks(Hainan Tropical Rainforest National Park,HTR;Wuyishan National Park,WYS;and Northeast Tiger and Leopard National Park,NTL)of China with less human interference as cases,which are distributed in different climatic zones,including tropical,subtropical and temperate monsoon climates,respectively.Then,we employed the probabilistic decay method to explore the spatio-temporal changes in the VR and their natural driving patterns using Geographically Weighted Regression(GWR)model as well.The results revealed that:(1)from 2000 to 2020,the Normalized Difference Vegetation Index(NDVI)of the three national parks fluctuated between 0.800 and 0.960,exhibiting an overall upward trend,with the mean NDVI of NTL(0.923)>HTR(0.899)>WYS(0.823);(2)the positive trend decay time of vegetation exceeded that of negative trend,indicating vegetation gradual recovery of the three national parks since 2012;(3)the VR of HTR was primarily influenced by elevation,aspect,average annual temperature change(AATC),and average annual precipitation change(AAPC);the WYS'VR was mainly affected by elevation,average annual precipitation(AAP),and AAPC;while the terrain factors(elevation and slope)were the main driving factors of VR in NTL;(4)among the main factors influencing the VR changes,the AAPC had the highest proportion in HTR(66.7%),and the AAP occupied the largest area proportion in WYS(80.4%).While in NTL,elevation served as the main driving factor for the VR,encompassing 64.2%of its area.Consequently,our findings indicated that precipitation factors were the main driving force for the VR changes in HTR and WYS national parks,while elevation was the main factors that drove the VR in NTL.Our research has promoted a deeper understanding of the driving mechanism behind the VR. 展开更多
关键词 National parks Vegetation resilience NDVI Probabilistic decay model Driving factors
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Exploring impacts of COVID-19 on spatial and temporal patterns of visitors to Canadian Rocky Mountain National Parks from social media big data
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作者 Dehui Christina Geng Amy Li +4 位作者 Jieyu Zhang Howie W.Harshaw Christopher Gaston Wanli Wu Guangyu Wang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期13-33,共21页
COVID-19 posed challenges for global tourism management.Changes in visitor temporal and spatial patterns and their associated determinants pre-and peri-pandemic in Canadian Rocky Mountain National Parks are analyzed.D... COVID-19 posed challenges for global tourism management.Changes in visitor temporal and spatial patterns and their associated determinants pre-and peri-pandemic in Canadian Rocky Mountain National Parks are analyzed.Data was collected through social media programming and analyzed using spatiotemporal analysis and a geographically weighted regression(GWR)model.Results highlight that COVID-19 significantly changed park visitation patterns.Visitors tended to explore more remote areas peri-pandemic.The GWR model also indicated distance to nearby trails was a significant influence on visitor density.Our results indicate that the pandemic influenced tourism temporal and spatial imbalance.This research presents a novel approach using combined social media big data which can be extended to the field of tourism management,and has important implications to manage visitor patterns and to allocate resources efficiently to satisfy multiple objectives of park management. 展开更多
关键词 Tourism management Social media big data National parks COVID-19 Geographical weighted regression
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Path Tracking Controller Design of Automated Parking Systems via NMPC with an Instructible Solution
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作者 Liang Chen Zhaobo Qin +2 位作者 Manjiang Hu Yougang Bian Xiaoyan Peng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期353-367,共15页
Parking difficulties have become a social issue that people have to solve.Automated parking system is practicable for quick par operations without a driver which can also greatly reduces the probability of parking acc... Parking difficulties have become a social issue that people have to solve.Automated parking system is practicable for quick par operations without a driver which can also greatly reduces the probability of parking accidents.The paper proposes a Lyapunov-based nonlinear model predictive controller embedding an instructable solution which is generated by the modified rear-wheel feedback method(RF-LNMPC)in order to improve the overall path tracking accuracy in parking conditions.Firstly,A discrete-time RF-LNMPC considering the position and attitude of the parking vehicle is proposed to increase the success rate of automated parking effectively.Secondly,the RF-LNMPC problem with a multi-objective cost function is solved by the Interior-Point Optimization,of which the iterative initial values are described as the instructable solutions calculated by combining modified rear-wheel feedback to improve the performance of local optimal solution.Thirdly,the details on the computation of the terminal constraint and terminal cost for the linear time-varying case is presented.The closed-loop stability is verified via Lyapunov techniques by considering the terminal constraint and terminal cost theoretically.Finally,the proposed RF-LNMPC is implemented on a selfdriving Lincoln MKZ platform and the experiment results have shown improved performance in parallel and vertical parking conditions.The Monte Carlo analysis also demonstrates good stability and repeatability of the proposed method which can be applied in practical use in the near future. 展开更多
关键词 Automated parking Path tracking controller Nonlinear model predictive control Monte Carlo analysis
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Collision-free parking recommendation based on multi-agent reinforcement learning in vehicular crowdsensing
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作者 Xin Li Xinghua Lei +1 位作者 Xiuwen Liu Hang Xiao 《Digital Communications and Networks》 SCIE CSCD 2024年第3期609-619,共11页
The recent proliferation of Fifth-Generation(5G)networks and Sixth-Generation(6G)networks has given rise to Vehicular Crowd Sensing(VCS)systems which solve parking collisions by effectively incentivizing vehicle parti... The recent proliferation of Fifth-Generation(5G)networks and Sixth-Generation(6G)networks has given rise to Vehicular Crowd Sensing(VCS)systems which solve parking collisions by effectively incentivizing vehicle participation.However,instead of being an isolated module,the incentive mechanism usually interacts with other modules.Based on this,we capture this synergy and propose a Collision-free Parking Recommendation(CPR),a novel VCS system framework that integrates an incentive mechanism,a non-cooperative VCS game,and a multi-agent reinforcement learning algorithm,to derive an optimal parking strategy in real time.Specifically,we utilize an LSTM method to predict parking areas roughly for recommendations accurately.Its incentive mechanism is designed to motivate vehicle participation by considering dynamically priced parking tasks and social network effects.In order to cope with stochastic parking collisions,its non-cooperative VCS game further analyzes the uncertain interactions between vehicles in parking decision-making.Then its multi-agent reinforcement learning algorithm models the VCS campaign as a multi-agent Markov decision process that not only derives the optimal collision-free parking strategy for each vehicle independently,but also proves that the optimal parking strategy for each vehicle is Pareto-optimal.Finally,numerical results demonstrate that CPR can accomplish parking tasks at a 99.7%accuracy compared with other baselines,efficiently recommending parking spaces. 展开更多
关键词 Incentive mechanism Non-cooperative VCS game Multi-agent reinforcement learning Collision-free parking strategy Vehicular crowdsensing
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Spatial-temporal Patterns of Urban Parks’Effects on the Sentiments and Their Associated Factors Based on Social Media Data——a Case Study in Beijing
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作者 YUAN Yuting WANG Juan +3 位作者 WEI Yali ZHU Yanrong SHI Changsheng MENG Bin 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第2期95-110,共16页
As the pivotal green space,urban parks play an important role in urban residents’daily activities.Thy can not only bring people physical health,but also can be more likely to elicit positive sentiment to those who vi... As the pivotal green space,urban parks play an important role in urban residents’daily activities.Thy can not only bring people physical health,but also can be more likely to elicit positive sentiment to those who visit them.Recently,social media big data has provided new data sources for sentiment analysis.However,there was limited researches that explored the connection between urban parks and individual’s sentiments.Therefore,this study firstly employed a pre-trained language model(BERT,Bidirectional Encoder Representations from Transformers)to calculate sentiment scores based on social media data.Secondly,this study analysed the relationship between urban parks and individual’s sentiment from both spatial and temporal perspectives.Finally,by utilizing structural equation model(SEM),we identified 13 factors and analyzed its degree of the influence.The research findings are listed as below:①It confirmed that individuals generally experienced positive sentiment with high sentiment scores in the majority of urban parks;②The urban park type showed an influence on sentiment scores.In this study,higher sentiment scores observed in Eco-parks,comprehensive parks,and historical parks;③The urban parks level showed low impact on sentiment scores.With distinctions observed mainly at level-3 and level-4;④Compared to internal factors in parks,the external infrastructure surround them exerted more significant impact on sentiment scores.For instance,number of bus and subway stations around urban parks led to higher sentiment scores,while scenic spots and restaurants had inverse result.This study provided a novel method to quantify the services of various urban parks,which can be served as inspiration for similar studies in other cities and countries,enhancing their park planning and management strategies. 展开更多
关键词 urban parks sentiment analysis social media data SEM BEIJING
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Exploration of Operation and Maintenance Management Mode and Innovation Mechanism of Pilot Base of Chemical Park
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作者 Shenggan ZHU Tengfei SHANG 《Asian Agricultural Research》 2024年第9期16-18,22,共4页
Based on the current situation of the operation and maintenance management of the pilot base in many chemical parks in China,this paper conducts an in-depth exploration of the operation and maintenance management and ... Based on the current situation of the operation and maintenance management of the pilot base in many chemical parks in China,this paper conducts an in-depth exploration of the operation and maintenance management and innovation mode of the pilot base from the aspects of the evaluation of the pilot project entering the park,safety and environmental protection supervision,pilot mode,and industrialization mode of the pilot test results,so as to provide solutions for accelerating the process and industrialization of the pilot project and realizing the innovation value of the pilot base. 展开更多
关键词 CHEMICAL parks PILOT BASE Operation and maintenance Mode INDUSTRIALIZATION EXPLORATION
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