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The legacy effects of rubber defoliation period on the refoliation phenology,leaf disease,and latex yield

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Plant Diversity 2023年第1期45卷 98-103页

作者： De-Li Zhai jian-chu Xu Center for Mountain Futures Kunming Institute of BotanyKunming 650201YunnanChina Institute of Environment and Ecology School of the Environment and Safety EngineeringJiangsu University301 Xuefu RoadZhenjiang212013Jiangsu ProvinceChina Key Laboratory for Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming 650201YunnanChina East and Central Asia Regional Office World Agroforestry(ICRAF)Kunming 650201YunnanChina

The leaf phenology of trees has received particular attention for its crucial role in the global water and carbon balances,ecosystem,and species ***,current studies on leaf phenology have mainly focused on temperate trees,while few studies including tropical *** attention has been paid to globally extensive industrial *** plantations are important to both the local and global *** this study,we investigated the legacy effects of defoliation phenology on the following year’s leaf flushing,leaf disease,and also latex yield of rubber trees,an economically important tree to local people and the *** show that extended duration of defoliation increased the subsequent duration of refoliation and rates of infection by powdery mildew disease,but led to reduced latex yield in *** legacy effect of rubber defoliation may relate to the carbohydrate reserved in the trees.A longer duration of defoliation would consume more reserved carbohydrates,reducing available reserves for disease defense and latex *** duration of defoliation period was associated with either a lower temperature before the cessation of latex tapping in October-November and/or a higher temperature after the cessation of latex tapping in *** falling signals the end of photosynthetic activities in deciduous ***,the leaf falling phenology will impact ecological processes involving rubber *** findings indicated that the inclusion of defoliation periods in future rubber trees’ research,will be crucial to furthering our understanding of leaf flushing,powdery mildew disease,and latex yield.

关键词： Carbohydrate Defoliation Legacy effect Phenology rubber trees

紫苏叶总黄酮对APAP诱导的急性肝损伤的保护作用

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食品工业科技 2024年第14期45卷 344-351页

作者：孟庆霖褚齐宋健董红畅李贺林珈羽赵南晰北华大学药学院吉林吉林132000 吉林市中心医院病理科吉林吉林132011

目的:本文主要研究紫苏叶总黄酮(Perilla flavone,PF)纯化的最佳方法,以及其对对乙酰氨基酚(Paracetamol,APAP)诱导的急性肝损伤的保护作用及可能的作用机制。方法:采用单因素实验确定大孔树脂纯化紫苏叶总黄酮的最佳条件。将BALB/c雄... 详细信息

目的:本文主要研究紫苏叶总黄酮(Perilla flavone,PF)纯化的最佳方法,以及其对对乙酰氨基酚(Paracetamol,APAP)诱导的急性肝损伤的保护作用及可能的作用机制。方法:采用单因素实验确定大孔树脂纯化紫苏叶总黄酮的最佳条件。将BALB/c雄性小鼠随机分为6组,空白对照组(CON)、模型组(MOD)、联苯双酯组(DDB)、PF低剂量组(L-PF,12.5 mg/kg)、PF中剂量组(M-PF,25 mg/kg)、PF高剂量组(H-PF,50 mg/kg),连续灌胃给药15 d。末次给药1 h后,除CON组外,每组腹腔注射APAP建立肝损伤模型。测定小鼠血清中谷草转氨酶(AST)、谷丙转氨酶(ALT)水平;测定小鼠肝脏中丙二醛(MDA)、超氧化物歧物酶(SOD)、还原型谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-PX)的水平;对小鼠肝脏进行HE染色观察病理学变化;Western Blot法检测小鼠肝脏中Nrf2、Keap1和HO-1蛋白表达。结果:最佳纯化条件:D101树脂10 g,上样溶液浓度为2.0 mg/mL,上样体积为30 mL,50 mL的80%乙醇溶液洗脱,纯化后黄酮含量为70.32%±1.49%。与CON组比较,MOD组小鼠血清中AST、ALT表达显著升高(P<0.01),说明肝损伤造模成功。与MOD组比较,给予PF组小鼠肝脏指数、AST、ALT、MDA、GSH水平和Keap 1蛋白表达显著降低25%~60%(P<0.01或P<0.05),SOD、GSH-PX水平和Nrf2、HO-1蛋白表达水平显著升高15%~35%(P<0.01或P<0.05)。HE染色结果显示PF可有效改善APAP引起的肝损伤。结论:紫苏叶总黄酮对APAP诱导的急性肝损伤有一定的保护作用,其机制与调控氧化应激的Nrf2/HO-1信号通路相关。

关键词：紫苏总黄酮对乙酰氨基酚肝损伤

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寰椎压迫致颈内静脉狭窄的彩色多普勒超声表现

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中华神经外科杂志 2024年第6期40卷 602-605页

作者：褚桐苇杨敏刘旭东董健胡志强吉训明首都医科大学附属北京世纪坛医院超声科北京100038 首都医科大学附属北京世纪坛医院放射科北京100038 首都医科大学附属北京世纪坛医院神经外科北京100038 首都医科大学脑重大疾病研究中心北京脑重大疾病研究院北京100069

目的探讨脑鸣和(或)耳鸣患者寰椎压迫致颈内静脉狭窄的彩色多普勒超声表现.方法回顾性分析2020年9月至2023年3月首都医科大学附属北京世纪坛医院超声科行颈内静脉彩色多普勒超声检查的25例存在寰椎横突压迫致颈内静脉狭窄的脑鸣和(或)... 详细信息

目的探讨脑鸣和(或)耳鸣患者寰椎压迫致颈内静脉狭窄的彩色多普勒超声表现.方法回顾性分析2020年9月至2023年3月首都医科大学附属北京世纪坛医院超声科行颈内静脉彩色多普勒超声检查的25例存在寰椎横突压迫致颈内静脉狭窄的脑鸣和(或)耳鸣患者的临床资料.25例患者均经头颈部CT静脉成像(CTV)和手术证实为单侧寰椎横突压迫颈内静脉.对比分析其双侧颈内静脉各节段的管腔内径、面积、最高流速、最高压力梯度及平均血流量.结果患侧颈内静脉J1、J2、J3节段的内径和面积均小于健侧,差异均具有统计学意义(均P0.05);与健侧相比,患侧颈内静脉J2、J3段最高流速和最高压力梯度均较小,各节段的平均血流量均较小,差异均具有统计学意义(均P<0.05).结论寰椎压迫致颈内静脉狭窄在彩色多普勒超声上表现为患侧颈内静脉全段管腔内径、面积和平均血流量减小,J2、J3段最高流速减慢、最高压力梯度减小,可间接反映颈内静脉回流的通畅性.

关键词：静脉颈寰椎超声检查血流动力学脑鸣颈内静脉外源性狭窄

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Progress and prospect for high temperature single-phased magnetic ferroelectrics

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Chinese Science Bulletin 2008年第14期53卷 2097-2112页

作者： YU jian chu JunHao Functional Materials Research Laboratory Tongji University Shanghai 200092 China National Laboratory for Infrared Physics Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China

Magnetic ferroelectrics are one of the most important functional materials. The present bottleneck lim- iting applications of them is lacking of high-temperature single-phased ferromagnetic-ferroelectric multiferroics with strong magnetoelectric coupling effect. Here, those progresses of the mechanism for coexistence of ferroelectric and magnetic order, experimental and theoretical studies on single-phased magnetic ferroelectrics, and the relationship between magnetic structure and crystal symmetry are summarized. With examples of BiFeO3, BiMnO3 and Bi2FeCrO6, the difficulties encountered in this field are analyzed. At last, some prospects to develop high-temperature single-phased ferromagnetic-ferro- electric multiferroics are also presented.

关键词：磁电效应单相位复合物磁铁电质高温条件 BiFeO3 BiMnO3 Bi2CrFeO6

Recent development in biogeotechnology and its engineering applications

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Frontiers of Structural and Civil Engineering 2021年第5期15卷 1073-1096页

作者： Hanjiang LAI Shifan WU Mingjuan CUI jian chu Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China School of Civil and Environmental Engineering Nanyang Technological UniversitySingapore 639798Singapore College of Civil Engineering Fuzhou UniversityFuzhou 350108China

Microbial geotechnology or biogeotechnology is a new branch of geotechnical *** involves the use of microbiology for traditional geotechnical *** new innovative soil improvement methods have been developed in recent years based on this approach.A proper understanding of the various approaches and the performances of different methods can help researchers and engineers to develop the most appropriate geotechnical *** present,most of the methods can be categorized into three major types,biocementation,bioclogging,and biogas *** and differences of different approaches and their potential applications are *** affecting the different processes are also *** of up-scaled model tests and pilot trials are presented to show the emerging *** challenges and problems of biogeotechnology are also discussed.

关键词： biogeotechnology biocementation bioclogging biogas strength enhancement liquefaction mitigation seepage control

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无人机高电压输电线路障碍物检测方法

电子设计工程 2024年第15期32卷 133-136,141页

作者：储剑贾云飞南京理工大学机械工程学院江苏南京210095

针对电力巡检无人机在高电压输电线路遇到的各种障碍物及其特点,该文提出了一种基于视觉TF-Net障碍物检测算法。该算法通过巡检无人机上的双目摄像头获取图像,并利用障碍物的几何形状和图像特征确定障碍物类型,结合摄像头和障碍物之间... 详细信息

针对电力巡检无人机在高电压输电线路遇到的各种障碍物及其特点,该文提出了一种基于视觉TF-Net障碍物检测算法。该算法通过巡检无人机上的双目摄像头获取图像,并利用障碍物的几何形状和图像特征确定障碍物类型,结合摄像头和障碍物之间的位置关系计算出障碍物到无人机的距离,以判断是否会影响无人机的正常飞行。研究采用了局部敏感提取、Ghost-Group卷积单元等方法,并对神经网络进行了轻量化处理,以最大化降低功耗。实验结果表明,相对于传统的卷积算法,该算法FPS提升了10 frames/s,平均精度(mAP)提升了6%。该算法在检测精度和检测速度上较普通算法框架都有一定提升。

关键词：无人机电力巡检障碍物检测视觉

彩色多普勒超声对颈内静脉骨性压迫性狭窄所致脑鸣或耳鸣手术疗效的初步观察

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中华神经外科杂志 2024年第7期40卷 708-711页

作者：刘旭东杨敏褚桐苇董健胡志强吉训明首都医科大学附属北京世纪坛医院超声科北京100038 首都医科大学附属北京世纪坛医院放射科北京100038 首都医科大学附属北京世纪坛医院神经外科北京100038 首都医科大学脑重大疾病研究中心北京脑重大疾病研究院北京100069

目的初步探讨彩色多普勒超声(CDU)对寰椎横突或茎突压迫所致颈内静脉(IJV)狭窄引起脑鸣或耳鸣患者的手术效果的评估价值。方法回顾性分析2020年9月至2023年3月于首都医科大学附属北京世纪坛医院神经外科收治的8例IJV狭窄所致脑鸣或耳鸣... 详细信息

目的初步探讨彩色多普勒超声(CDU)对寰椎横突或茎突压迫所致颈内静脉(IJV)狭窄引起脑鸣或耳鸣患者的手术效果的评估价值。方法回顾性分析2020年9月至2023年3月于首都医科大学附属北京世纪坛医院神经外科收治的8例IJV狭窄所致脑鸣或耳鸣患者的临床资料。所有患者均经CT静脉成像(CTV)确诊,证实均存在因寰椎横突或茎突压迫导致的IJV狭窄。8例患者行寰椎横突或茎突部分磨除减压术后,于术前1周、术后1周内、术后3~6个月行CDU检查,分析IJV管径、平均血流量(FVm)和最大血流速度(Vmax)的变化。结果8例患者术后1周内的IJV各节段管径和FVm与术前的差异无统计学意义(均P>0.05)。术后3~6个月,IJV J1和J2段的管径较术前显著增加[J1段:(9.52±2.09)mm对比(7.45±2.10)mm;J2段:(6.75±1.74)mm对比(5.52±1.91)mm](均P0.05);IJV各节段的FVm均较术前改善[J1段:(349.20±188.99)ml/min对比(204.60±118.50)ml/min;J2段:(193.10±91.32)ml/min对比(124.50±81.57)ml/min;J3段:(152.70±95.71)ml/min对比(61.90±53.23)ml/min](均P0.05)。结论初步观察显示,寰椎横突或茎突部分磨除手术可改善IJV骨性压迫性狭窄所致脑鸣或耳鸣患者IJV狭窄段的管径及血流动力学,CDU可作为IJV骨性压迫性狭窄病变手术疗效的客观评估手段。

关键词：颈静脉减压术,外科超声检查,多普勒,彩色脑鸣治疗结果

指向高阶思维培养的PBL学习活动模型设计研究

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黑河学院学报 2024年第8期15卷 89-92页

作者：谢建周涵婕褚丹阜阳师范大学教育学院安徽阜阳236000

随着人工智能技术的快速发展,高阶思维能力成为个体竞争力的关键。基于问题的学习(PBL)作为一种有效的教学方法,旨在通过引导学生主动探索、合作与交流,培养其问题解决能力、创新思维和自主学习能力。然而,当前PBL实践研究对高阶思维的... 详细信息

随着人工智能技术的快速发展,高阶思维能力成为个体竞争力的关键。基于问题的学习(PBL)作为一种有效的教学方法,旨在通过引导学生主动探索、合作与交流,培养其问题解决能力、创新思维和自主学习能力。然而,当前PBL实践研究对高阶思维的影响研究不足。深入分析高阶思维及问题解决理论,构建面向高阶思维培养的学生问题解决能力模型。通过探索数字化学习中的自主、探究、合作途径,为PBL教学实践提供理论支持和实践指导,旨在培养具备高阶思维能力的创新人才。

关键词：基于问题的学习 PBL 高阶思维学习模型

Reliable H-infinity filtering for linear systems with sensor saturation

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控制理论与应用（英文版） 2013年第1期11卷 80-85页

作者： Ting SHI Hongye SU jian chu Institute of Automation Hangzhou Dianzi University State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and Control Zhejiang University (Yuquan Campus)

In this paper, a new reliable H-infinity filter design problem is proposed for a class of continuous-time sys- tems with sensor saturation and failures. Attention is focused on the analysis and synthesis problems of a full order reliable H-infinity filter such that the filtering error dynamics is asymptotically stable with a guaranteed disturbance rejection atten- uation level -y. It is shown that the filtering error dynamics obtained from the original system plus the filter can be modeled by a linear system with sector bounded nonlinearity. The design conditions are given in terms of solutions to a set of linear matrix inequalities （LMIs）. These conditions are then considered in a convex optimization problem with LMIs constraints in order to design an optimal reliable H-infinity filter. A numerical example is given to illustrate the effectiveness of the proposed results.

关键词： H-infinity filtering Reliable filtering Sensor saturation Sensor failures Linear matrix inequality