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基于混合像元分解的分蘖期水稻基本苗数量估测方法研究

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农业机械学报 2024年第6期55卷 202-209页

作者：朱文静戴世元冯展康段凯文邵长锋魏新华江苏大学农业工程学院镇江212013 江苏大学现代农业装备与技术教育部重点实验室镇江212013

基本苗数量是反映水稻健康水平的重要依据,在分蘖期精准估测水稻基本苗数量可以指导后期的施肥量,从而调控水稻的最佳分蘖数。同时,对水稻长势监测和产量预测具有非常重要的意义。针对传统田间人工统计基本苗数量耗时长、成本高等问题,... 详细信息

基本苗数量是反映水稻健康水平的重要依据,在分蘖期精准估测水稻基本苗数量可以指导后期的施肥量,从而调控水稻的最佳分蘖数。同时,对水稻长势监测和产量预测具有非常重要的意义。针对传统田间人工统计基本苗数量耗时长、成本高等问题,以江苏大学附属农场镇江润果农场分蘖期水稻为研究对象,利用大疆无人机(M600 pro型)搭载多光谱相机(Rededge-MX型)获取水稻分蘖期多光谱数据,对原始图像进行图像拼接、辐射校正、几何校正等预处理操作,根据像元纯度系数提取土壤端元和植被端元,建立波谱库,然后按照完全约束最小二乘法的方法执行混合像元分解,构建植被覆盖度和水稻基本苗数量的回归模型。该研究方法获得的模型决定系数R^(2)为0.891,均方根误差RMSE为4.6株/m^(2)。而传统的像元二分法模型(基于NDVI、VDVI和GNDVI植被指数计算植被覆盖度),其决定系数R2为0.834、0.744、0.642,其RMSE为5.7、7.1、8.4株/m^(2)。试验结果表明,基于完全约束最小二乘法的混合像元分解模型评价指标均优于像元二分法模型。本文基于混合像元分解方法有效提高了水稻基本苗统计精度,并且生成了水稻基本苗数量反演图,可以直观统计基本苗数量,为分蘖期水稻补苗、间苗提供指导。

关键词：水稻基本苗混合像元分解完全约束最小二乘法像元二分法

不同材质瑜伽垫对女性垫上运动生物力学关键指标的影响研究

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浙江体育科学 2024年第4期46卷 78-86页

作者：刘鑫严翝钧但林飞陆毅琛李建设宁波大学体育学院浙江宁波315211 宁波市博瀚工艺品有限公司浙江宁波315300 浙江药科职业大学浙江宁波315599

目的:通过对比EVA、NBR、pU+NR及TpE四种不同材质的瑜伽垫,分析不同材质瑜伽垫对女性垫上健身动作的下肢生物力学影响,并探讨不同材质瑜伽垫的缓震性和支撑稳定性。方法:选取24名健康女性大学生,近半年内无任何下肢损伤,跳箱单腿着地试... 详细信息

目的:通过对比EVA、NBR、pU+NR及TpE四种不同材质的瑜伽垫,分析不同材质瑜伽垫对女性垫上健身动作的下肢生物力学影响,并探讨不同材质瑜伽垫的缓震性和支撑稳定性。方法:选取24名健康女性大学生,近半年内无任何下肢损伤,跳箱单腿着地试验用于缓震性测试评估,瑜伽单腿支撑试验用于稳定性测试评估。采用Vicon三维运动捕捉系统、AMTI三维测力台测试系统对着地动作的下肢运动学和动力学参数c进行同步采集;使用Footscan平板式足底压力测试系统对单腿支撑动作的足底各区域压力参数进行采集。结果:①在不同材质瑜伽垫上着地,膝、踝关节的若干运动学和动力学参数存在显著性差异(ppU+NR垫,pU+NR垫的膝内收力矩显著小于NBR垫和TpE垫,膝内旋力矩显著小于TpE垫。②不同材质瑜伽垫对足底压力、压强峰值及压力中心位移量的影响存在显著性差异(ppU+NR垫和TpE垫;第2~5趾骨区,NBR垫压力峰值显著小于pU+NR垫;足跟内侧区,NBR垫压力峰值显著大于EVA、pU+NR及TpE垫;EVA瑜伽垫在Y轴的身体前-后侧平均位移量最小,与其他3种瑜伽垫存在显著性差异。结论:①NBR瑜伽垫过大的踝外翻角度、膝外展力矩及垂直地面反作用力均可能造成更大的下肢关节损伤风险。pU+NR瑜伽垫良好的缓震性能可以更大程度地吸收着地冲击力,有助于降低膝关节着地负荷。②NBR瑜伽垫最大压强峰值出现在足跟内侧,足外翻过度风险更大;pU+NR瑜伽垫的最大压强峰值主要分布在趾骨区、跖骨区及足跟区,该支撑方式有利于足底肌群协调发力;EVA瑜伽垫的压力中心在前后方向的位移幅度较小,有助于保持单腿支撑动作的稳定性。

关键词：瑜伽垫材质垫上运动下肢生物力学运动损伤

MADS Box Transcript Amount is Affected by Ethylene during Abscission

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American Journal of plant Sciences 2011年第3期2卷 308-317页

作者： Valeriano dal cin Angelo Ramina 不详

Thinning of young fruit is an important agronomical practice to ensure the maximum economic production. This practice is based on the control of the natural self thinning process occurring during fruit development. At the early stages of fruit development (fruitlet), the vegetative part of the tree is competing with the reproductive part of the tree and within the fruit clusters the different fruitlets are competing with each other. As a result the least fit organ abscises, Ethylene and auxin play a central role in this event but the role of ethylene is not thoroughly understood because in other systems abscission occurs partly with ethylene independent processes. We have followed the early development of fruitlets and studied the transcription patterns of MADS-box and ethylene related transcripts. Furthermore, we verified that ethylene has an effect on the expression of some ethylene related and MADS BOX genes. We propose that the ethylene burst during abscission induction is similar to a stage 2 ethylene system and it is related to fruitlet growth by affecting transcript amount of MADS-BOXes which modulate seed development and cortex growth.

关键词： Apple MADS-BOX Ethylene Fruit Ripening

Cavity effect on Rayleigh wave dispersion and p-wave refraction

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 79-88页

作者： Hossein Rahnema Sohrab Mirassi Giancarlo dal Moro Department of Civil and Environmental Engineering Shiraz University of TechnologyShirazIran Department of Civil Engineering Shahrekord BranchIslamic Azad UniversityShahrekordIran Institute of Rock Structure and Mechanics Academy of Sciences of the Czech RepublicPragueCzech Republic

Sinkholes and cavities can represent serious hazards to human safety and urban infrastructures,cause roadbed subsidence,and so *** is therefore essential to evaluate various sinkholes in different depths and sizes to assess the risk of *** paper evaluates the effect of different cavities on Rayleigh-wave propagation and body(p)wave ***(R)wave propagation is analyzed according to the classical multi-channel analysis of surface waves(MASW)method also considering the R-wave *** seismic traces are computed by means of finite element modeling(FEM)for cavity and intrusion at different depths and ***,field acquisition data is used to verify the detection effect of a cavity on R-and *** results show that the presence of backscattered R-waves and the changes in the R-wave velocity spectrum can help in cavity *** possible evidence is represented by significant changes in the refraction travel times over the cavity *** can be concluded that the field data are in good agreement with the synthetic,and it could be effective to consider the results of both R-and p-wave analysis in order to efficiently identify the cavities.

关键词： R-wave velocity spectrum p-wave refraction cavity intrusion backscattered waves finite element modeling(FEM) MASW method

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容错计算机系统的可用性分析

航空计算技术 1981年第3期 43-53页

作者： Mario dal cin 刘学君

本文应用网络排队论来决定容错多重处理机计算机系统的可用性。计算了系统装置的平均修复时间及利用率。子系统的可用性是通过对网络排队论进行分解的方法取得的。

关键词：尺口排队论数学理论可用性

Molecular mechanisms of liver preconditioning

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World Journal of Gastroenterology 2010年第48期16卷 6058-6067页

作者： Elisa Alchera Caterina dal ponte Chiara Imarisio Emanuele Albano Rita Carini Department of Medical Sciences University of East Piedmont "A. Avogadro"

Ischemia/reperfusion (I/R) injury still represents an important cause of morbidity following hepatic surgery and limits the use of marginal livers in hepatic transplantation. Transient blood flow interruption followed by reperfusion protects tissues against damage induced by subsequent I/R. This process known as ischemic pre-conditioning (Ip) depends upon intrinsic cytoprotective systems whose activation can inhibit the progression of irreversible tissue damage. Compared to other organs,liver Ip has additional features as it reduces inflammation and promotes hepatic regeneration. Our present understanding of the molecular mechanisms involved in liver Ip is still largely incomplete. Experimental studies have shown that the protective effects of liver Ip are triggered by the release of adenosine and nitric oxide and the subsequent activation of signal networks involving protein kinases such as phosphatidylinositol 3-kinase,protein kinase C δ/ε and p38 MAp kinase,and transcription factors such as signal transducer and activator of transcription 3,nuclear factor-κB and hypoxia-inducible factor 1. This article offers an overview of the molecular events underlying the preconditioning effects in the liver and points to the possibility of developing pharmacological approaches aimed at activating the intrinsic protective systems in patients undergoing liver surgery.

关键词： Apoptosis Hepatocyte Hypoxia Ischemia/ reperfusion Liver surgery Necrosis pharmacological preconditioning preconditioning Survival pathways

CCSD主孔高Ti榴辉岩非耦合的高Ti、低Nb(Zr)特征:对玄武质岩浆房中磁铁矿分离结晶作用的指示

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岩石学报 2005年第2期21卷 339-346页

作者：刘勇胜张泽明 Lee cin-Ty 高山宗克清中国地质大学地质过程与矿产资源国家重点实验室中国地质科学院地质研究所北京100037 Department of Earth Science

利用XRF和HR-ICp-MS对中国大陆科学钻探工程(CCSD)主孔<700m深度高Ti榴辉岩进行了准确分析研究。结果表明高Ti榴辉岩以TFeO和Eu异常之间的相关性及非耦合的高TiO2(2.4-5.7%)、低Nb(<5.5μg/g)和Zr(<98μg/g)为特征。而且,这些榴辉岩的T... 详细信息

利用XRF和HR-ICp-MS对中国大陆科学钻探工程(CCSD)主孔p=2.61-2.76g/cm3)低于正常玄武岩熔体(p=2.8-3.0g/cm3),因此玄武岩岩浆房中结晶出的斜长石在岩浆演化早期不会和熔体分离而形成堆晶岩。磁铁矿的密度(p=5.1-5.2g/cm3)远远高于玄武岩熔体。磁铁矿的结晶分离会显著降低玄武岩熔体的局部密度而诱发斜长石晶体分离下沉并形成富集斜长石的高Fe堆晶岩。这种机制很好地解释了高Ti榴辉岩所具有的TFeO和Eu异常之间的相关性及非耦合的高TiO2(2.4-5.7%)、低Nb(<5.5μg/g)和Zr(<98μg/g)特征。本文研究表明在CCSD中的高Ti榴辉岩原岩应是由同一玄武岩岩浆房中富磁铁矿结晶作用形成的堆晶岩。高Ti榴辉岩的Ti矿化本质上源于磁铁矿结晶作用,而与其经历的超高压变质作用无关。

关键词：高-Ti榴辉岩原岩 CCSD 高场强元素磁铁矿

pulmonary administration of functionalized nanoparticles significantly reduces beta-amyloid in the brain of an Alzheimer＇s disease murine model

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Nano Research 2016年第7期9卷 2190-2201页

作者： Giulio Sancini Roberta dal Magro Francesca Ornaghi Claudia Balducci Gianluigi Forloni Marco Gobbi Mario Salmona Francesca Re Nanomedicine Center School of Medicine and Surgery University of Milano-Bicocca via Cadore 48 20900 Monza (MB) Italy Department ofNeuroscience IRCCS-Istituto di Ricerche Farmacologiche Mario Negri via La Masa 19 20159 Milano Italy Department of Biochemistry and Molecular pharmacology IRCCS-Istituto di Ricerche Farmacologiche Mario Negri via La Masa 19 20159 Milano Italy

Treatment options for Alzheimer＇s disease （AD） are limited because of the inability of drugs to cross the blood-brain barrier （BBB）. A promising strategy to overcome this obstacle is the use of nanoparticles （Nps）. previously, we showed that intraperitoneal administration of liposomes functionalized with phosphatidic acid and an ApoE-derived peptide （mApoE-pA-LIp） reduces brain beta-amyloid （A） burden and ameliorates impaired memory in AD mice. Here, we investigated lung administration as an alternative, non-invasive Np delivery route for reaching the brain. Our results show that mApoE-pA-LIp were able to cross the pulmonary epithelium （[C]-pA permeability = 6.5 ＋ 2.0 × 10^4 cm/min） in vitro and reach the brain （up to 0.6 μg pA/g brain） following in vivo intratracheal instillations. Lung administration of mApoE-pA-LIp to AD mice significantly decreased total brain Aβ （-60%; p 〈 0.05） compared to untreated mice. These results suggest that pulmonary administration could be exploited for brain delivery of Nps designed for AD therapy.

关键词： ApoE-derived peptide lung administration nanoparticles Alzheimer's disease liposomes

Effects of a multimodal exercise protocol on functional outcomes,epigenetic modulation and brain-derived neurotrophic factor levels in institutionalized older adults:a quasi-experimental pilot study

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Neural Regeneration Research 2021年第12期16卷 2479-2485页

作者： Iasmin Fraga Camila Weber Wériton Baldo Galiano Lucio Iraci Mariana Wohlgemuth Gabriela Morales Camila Cercato Juliana Rodriguez Daniela pochmann Caroline Dani pérsia Menz Adriane dal Bosco Viviane Rostirola Elsner programa de pós-Graduação em Ciências Biológicas:Fisiologia Universidade Federal do Rio Grande do SulPorto AlegreRSBrasil Curso de Fisioterapia do Centro Universitário Metodista-IpA Porto AlegreRSBrasil programa de pós-Graduação em Biociências e Reabilitação Centro Universitário Metodista-IPAPorto AlegreRSBrasil physiotherapist working in Long-Term InstitutionsPorto AlegreRSBrasil

Epigenetic changes have been shown to be associated with both aging process and aging-related *** is evidence regarding the benefits of physical activity on the functionality,cognition,and quality of life of institutionalized older adults,however,the molecular mechanisms involved are not *** purpose of this pilot study was to investigate the effects of a multimodal exercise intervention on functional outcomes,cognitive performance,quality of life(QOL),epigenetic markers and brain-derived neurotrophic factor(BDNF)levels among institutionalized older adult ***(n=8)without dementia who were aged 73.38±11.28 years and predominantly female(87.5%)were included in this quasi-experimental pilot study.A multimodal exercise protocol(cardiovascular capacity,strength,balance/agility andﬂexibility,perception and cognition)consisted of twice weekly sessions(60 minutes each)over 8 ***(Berg Scale),mobility(Timed Up and Go test),functional capacity(Six-Minute Walk test),cognitive function(Mini-Mental State Examination)and QOL(the World Health Organization Quality of Life-BREF Scale questionnaire)were evaluated before and after the *** sample(15 mL)was also collected before and after intervention for analysis of biomarkers global histone H3 acetylation and brain-derived neurotrophic factor *** improvements were observed in cognitive function,balance,mobility,functional capacity and QOL after the *** addition,a tendency toward an increase in global histone H3 acetylation levels was observed,while brain-derived neurotrophic factor level remained *** study provided evidence that an 8-week multimodal exercise protocol has a significant effect on ameliorating functional outcomes and QOL in institutionalized older adult *** addition,it was also able to promote cognitive improvement,which seems to be partially related to histone hyperacetylation *** Ethics Research Com

关键词： aging balance brain-derived neurotrophic factor cognition epigenetics physical exercise quality of life risk of falling