检索结果-南通市图书馆

SPSI:A Novel Composite Index for Estimating Panicle Number in Winter Wheat before Heading from UAV Multispectral Imagery

在线全文

学校读者我要写书评

暂无评论

Plant Phenomics 2023年第3期5卷 642-656页

作者： Yapeng Wu Wenhui Wang Yangyang gu Hengbiao zheng Xia Yao Yan Zhu Weixing Cao tao Cheng National Engineering and Technology Center for Information Agriculture(NETCIA) MARA Key Laboratory for Crop System Analysis and Decision MakingMOE Engineering Research Center of Smart AgricultureJiangsu Key Laboratory for Information AgricultureNanjing Agricultural UniversityOne WeigangNanjingJiangsu 210095PR China Langfang Normal University 100 Aimin West RoadLangfangHebei 065000PR China

Rapid and accurate estimation of panicle number per unit ground area(PNPA)in winter wheat before heading is crucial to evaluate yield potential and regulate crop growth for increasing the final yield.The accuracies of existing methods were low for estimating PNPA with remotely sensed data acquired before heading since the spectral saturation and background effects were ignored.This study proposed a spectral-textural PNPA sensitive index(SPSI)from unmanned aerial vehicle(UAV)multispectral imagery for reducing the spectral saturation and improving PNPA estimation in winter wheat before heading.The effect of background materials on PNPA estimated by textural indices(TIs)was examined,and the composite index SPSI was constructed by integrating the optimal spectral index(SI)and TI.Subsequently,the performance of SPSI was evaluated in comparison with other indices(SI and TIs).The results demonstrated that green-pixel TIs yielded better performances than all-pixel TIs apart from TI_([HOM]),TI_([ENT]),and TI_([SEM])among all indices from 8 types of textural features.SPSI,which was calculated by the formula DATT_([850,730,675])+NDTICOR_([850,730]),exhibited the highest overall accuracies for any date in any dataset in comparison with DATT_([850,730,675]),TINDRE_([MEA]),and NDTICOR_([850,730]).For the unified models assembling 2 experimental datasets,the RV^(2) values of SPSI increased by 0.11 to 0.23,and both RMSE and RRMSE decreased by 16.43%to 38.79%as compared to the suboptimal index on each date.These findings indicated that the SPSI is valuable in reducing the spectral saturation and has great potential to better estimate PNPA using high-resolution satellite imagery.

关键词： heading Wheat indices

Spatiotemporal Changes of Snow Depth in Western Jilin,China from 1987 to 2018

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Geographical Science 2024年第2期34卷 357-368页

作者： WEI Yanlin LI Xiaofeng gu Lingjia zheng Zhaojun zheng Xingming JIANG tao Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Changchun Jingyuetan Remote Sensing Experiment Site Chinese Academy of SciencesChangchun 130102China College of Electronic Science and Engineering Jilin UniversityChangchun 130012 National Meteorological Satellite Meteorological Center Beijing 100081China

Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming conditions.However,the spatiotemporal snow cover patterns are challenging in western Jilin,China due to natural condi-tions and sparse observation.Hence,this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive mi-crowave(PMW)snow depth(SD)data from 1987 to 2018,and revealed the potential influence of climate factors on SD variations.The results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend(P>0.05)at a rate of 0.009 cm/yr.In snowmelt periods,the snow cover contributed to an increase in volumetric soil water,and the change in SD was significantly affected by air temperature.The correlation between SD and air temperature was negative,while the correlation between SD and precipitation was positive during December and March.In March,the correlation coefficient exceeded 0.5 in Zhenlai,Da’an,Qianan,and Qianguo counties.However,the SD and precipitation were neg-atively correlated over western Jilin in October,and several subregions presented a negative correlation between SD and precipitation in November and April.

关键词： snow cover snow depth(SD) climate changes passive microwave(PMW) western Jilin,China

Effect of Mn Modification on the Corrosion Susceptibility of Mg–Mn Alloys by Magnesium Scrap

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2021年第1期34卷 1-11页

作者： Dong-Dong gu Jian Peng Jia-Wen Wang zheng-tao Liu Fu-Sheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Chongqing Research Center for Advanced Materials Chongqing Academy of Science and TechnologyChongqing 401123China

The microstructure and anti-corrosion behavior of Mg–Mn alloys by magnesium scrap have been investigated in this study.The results show that the size of the Fe-rich particles in magnesium scrap decreases but the quantity increases with the Mn addition.Although the presence of Mn-containing Fe-rich particles with unique symbiotic structure can eff ectively weaken the micro-galvanic corrosion,the presence of more free Fe(Fe-rich particles)does not necessarily lead to severe corrosion of the alloy.The corrosion susceptibility of Mg–Mn–Fe alloy primarily depends on the solubility of iron in the Mg matrix,while it can be significantly reduced by suitable Mn addition.Besides,the tolerance limit of the Fe impurity can be expressed as Femax=0.0083 Mn(relative to the iron solubility).Only when the Fe/Mn ratio is below 0.0083 can the alloy have excellent corrosion resistance,with the corrosion rate changing in the scope of 0.38±0.09 to 0.54±0.15 mg/cm^(2) day and icorr from 3 to 9×10^(–4) A/cm^(2).

关键词： Magnesium scrap Mn modification Fe impurity Corrosion susceptibility Corrosion resistance

A novel fine-resolution snow depth retrieval model to revealdetailed spatiotemporal patterns of snow cover in NortheastChina

在线全文

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2023年第1期16卷 1164-1185页

作者： Yanlin Wei Xiaofeng Li Lingjia gu Xingming zheng tao Jiang Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchunPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Changchun Jingyuetan Remote Sensing Experiment Site Chinese Academy of SciencesChangchunPeople’s Republic of China College of Electronic Science&Engineering Jilin UniversityChangchunPeople’s Republic of China

Seasonal snow cover is a key component of the global climate and hydrological system,it has drawn considerable attention under global warming conditions.Although several passive microwave(PMW)snow depth(SD)products have been developed since the 1970s,they inherit noticeable errors and uncertainties when representing spatial distributions and temporal changes of SD,especially in complex mountainous regions.In this paper,we developed afine-resolution SD retrieval model(FSDM)using machine learning to improve SD estimation quality for Northeast China and produced a long-term,fine-resolution,daily SD dataset.The accuracies of the FSDM dataset were evaluated against in-situ SD data along with existing SD products.The results showed the FSDM dataset provided satisfactory inversion accuracy in spatiotemporal evaluation,with the root-mean-square error(RMSE),bias,and correlation coefficient(R)of 7.10 cm,-0.13 cm,and 0.60.Additionally,we analyzed the spatiotemporal variations of SD in Northeast China and found that snow cover was mainly distributed in the Greater Khingan Range,Lesser Khingan Mountains,and Changbai Mountain regions.The SD exhibited high-low distribution patterns with the increased latitude.The annual mean SD slightly increased at the rate of 0.029 cm/year during 1987-2018.

关键词： Passive microwave remote sensing snow depth inversion machine learning fine resolution Northeast China

A systematic survey on the diagnosis strategy and patient management of type 1 diabetes by Chinese physicians

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2018年第3期61卷 318-327页

作者： Yong gu Hsiang-Ting Hsu Jing Zhu Xuqin zheng Hemin Jiang Hongqi Fan tao Yang Department of Endocrinology & Metabolism First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China Jiangsu Medical Quality Control Center (Endocrinology and Metabolism) Nanjing 210008 China

The qualification of physicians is a key factor in controlling type 1 diabetes(T1 D) since they provide crucial information to their patients about self-management. To investigate whether Chinese physicians' medical strategies influence the control of T1 D in their patients, we designed a questionnaire to survey Chinese physicians, which covered their diagnosis and patient-management strategies for T1 D. A total of 442 completed questionnaires were received from 35 public hospitals in 12 cities. The results showed Chinese physicians mainly diagnosed T1 D based on the clinical features and islet dysfunction. One-third of physicians in this study still prescribed non-basal-bolus insulin regimens to their T1 D patients. More than 80% of the doctors prescribed alpha-glucosidase inhibitors as adjunctive therapy, in addition to insulin therapy. Moreover, most of the physicians in China did not pay attention to identify coexistent autoimmune diseases. T1 D patients in China were not armed with self-management knowledge and skills, which should be provided by their doctors. One of the circumstances leading to insufficient disease control in Chinese T1 D patients is the ineffective therapeutic strategy prescribed by their physicians. We need to promote knowledge of efficient strategies among physicians in China to achieve better disease control in Chinese T1 D patients in the future.

关键词：诊断策略自我管理糖尿病医生中国类型疾病控制系统

Polydatin prevents the induction of secondary brain injury after traumatic brain injury by protecting neuronal mitochondria

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2019年第9期14卷 1573-1582页

作者： Li Li Hong-Ping Tan Cheng-Yong Liu Lin-tao Yu Da-Nian Wei Zi-Chen Zhang Kui Lu Ke-Sen Zhao Marc Maegele Dao-Zhang Cai Zheng-Tao Gu Department of Treatment Center for Traumatic Injuries the Third Affiliated Hospital of Southern Medical UniversityAcademy of Orthopedics·Guangdong ProvinceGuangzhouGuangdong ProvinceChina Department of Pathophysiology Southern Medical UniversityGuangdong Provincial Key Laboratory of Shock and Microcirculation ResearchGuangzhouGuangdong ProvinceChina Department of Epilepsy Surgery Guangdong Sanjiu Brain HospitalGuangzhouGuangdong ProvinceChina Department of Emergency the Third Affiliated Hospital of Southern Medical UniversityAcademy of Orthopedics·Guangdong ProvinceGuangzhouGuangdong ProvinceChina Department of Traumatology and Orthopedic Surgery Cologne-Merheim Medical Center(CMMC)University Witten/Herdecke(UW/H)Campus Cologne-MerheimCologneGermany Department of Orthopedics the Third Affiliated Hospital of Southern Medical UniversityAcademy of Orthopedics·Guangdong ProvinceGuangzhouGuangdong ProvinceChina

Polydatin is thought to protect mitochondria in different cell types in various diseases.Mitochondrial dysfunction is a major contributing factor in secondary brain injury resulting from traumatic brain injury.To investigate the protective effect of polydatin after traumatic brain injury,a rat brain injury model of lateral fluid percussion was established to mimic traumatic brain injury insults.Rat models were intraperitoneally injected with polydatin(30 mg/kg)or the SIRT1 activator SRT1720(20 mg/kg,as a positive control to polydatin).At 6 hours post-traumatic brain injury insults,western blot assay was used to detect the expression of SIRT1,endoplasmic reticulum stress related proteins and p38 phosphorylation in cerebral cortex on the injured side.Flow cytometry was used to analyze neuronal mitochondrial superoxide,mitochondrial membrane potential and mitochondrial permeability transition pore opened.Ultrastructural damage in neuronal mitochondria was measured by transmission electron microscopy.Our results showed that after treatment with polydatin,release of reactive oxygen species in neuronal mitochondria was markedly reduced;swelling of mitochondria was alleviated;mitochondrial membrane potential was maintained;mitochondrial permeability transition pore opened.Also endoplasmic reticulum stress related proteins were inhibited,including the activation of p-PERK,spliced XBP-1 and cleaved ATF6.SIRT1 expression and activity were increased;p38 phosphorylation and cleaved caspase-9/3 activation were inhibited.Neurological scores of treated rats were increased and the mortality was reduced compared with the rats only subjected to traumatic brain injury.These results indicated that polydatin protectrd rats from the consequences of traumatic brain injury and exerted a protective effect on neuronal mitochondria.The mechanisms may be linked to increased SIRT1 expression and activity,which inhibits the p38 phosphorylation-mediated mitochondrial apoptotic pathway.This study was approved by the Animal Care and Use Committe

关键词： nerve regeneration traumatic brain injury polydatin mitochondria endoplasmic reticulum stress SIRT1 reactive oxygen species p38 mitochondrial membrane potential mitochondrial permeability transition pore lateral fluid percussion neural regeneration

Current status and outlook of biodegradable metals in neuroscience and their potential applications as cerebral vascular stent materials

在线全文

学校读者我要写书评

暂无评论

Bioactive Materials 2022年第5期7卷 140-153页

作者： Ming Li Miaowen Jiang Yuan Gao Yufeng zheng Zhi Liu Chen Zhou tao Huang Xuenan gu Ang Li Jiancheng Fang Xunming Ji School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing100191China China-America Institute of Neuroscience Xuanwu HospitalCapital Medical UniversityBeijing100053China School of Materials Science and Engineering Peking UniversityBeijing100871China Department of Cardiology Xuanwu HospitalCapital Medical UniversityBeijing100053China Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijing100053China Department of Neuroscience Xuanwu HospitalCapital Medical UniversityBeijing100053China Department of Biomedical Engineering University of MelbourneParkvilleVIC3010Australia Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical EngineeringBeihang UniversityBeijing100083China Department of Biomedical Engineering Columbia UniversityNew YorkNY10032USA

Over the past two decades,biodegradable metals(BMs)have emerged as promising materials to fabricate temporary biomedical devices,with the purpose of avoiding potential side effects of permanent implants.In this review,we first surveyed the current status of BMs in neuroscience,and briefly summarized the representative stents for treating vascular stenosis.Then,inspired by the convincing clinical evidence on the in vivo safety of Mg alloys as cardiovascular stents,we analyzed the possibility of producing biodegradable cerebrovascular Mg alloy stents for treating ischemic stroke.For these novel applications,some key factors should also be considered in designing BM brain stents,including the anatomic features of the cerebral vasculature,hemodynamic influences,neuro-cytocompatibility and selection of alloying elements.This work may provide insights into the future design and fabrication of BM neurological devices,especially for brain stents.

关键词： Biodegradable metals Neuroscience Mg alloys Brain stents Ischemic stroke

Application of Intraoperative Contrast-Enhanced Ultrasound in the Resection of Brain Tumors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Medical Science 2022年第1期42卷 169-176页

作者： An-yu tao Xu CHEN Ling-yun ZHANG Yong CHEN Dan CAO zheng-qian guO Jian CHEN Department of Medical Ultrasound Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:To investigate the value of routine intraoperative ultrasound(IU)and intraoperative contrast-enhanced ultrasound(ICEUS)in the surgical treatment of brain tumors,and to explore the utilization of ICEUS for the removal of the remnants surrounding the resection cavity.Methods:In total,51 patients who underwent operations from 2012 to 2018 due to different tumors in the brain were included in this study.The clinical data were evaluated retrospectively.IU was performed in all patients,among which 28 patients underwent ICEUS.The effects of IU and ICEUS on tumor resection and recurrence were evaluated.

关键词： intraoperative ultrasound intraoperative contrast-enhanced ultrasound brain tumor hypervascular glioma

Thermally Conductive and Insulating Epoxy Composites by Synchronously Incorporating Si-sol Functionalized Glass Fibers and Boron Nitride Fillers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2020年第7期38卷 730-739,I0006页

作者： Rui-Han Zhang Xue-tao Shi Lin Tang zheng Liu Jun-Liang Zhang Yong-Qiang guo Jun-Wei gu Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi'an 710072China

Glass fibers(GFs)/epoxy laminated composites always present weak interlaminar shear strength(ILSS)and low cross-plane thermal conductivity coefficient(λ⊥).In this work,silica-sol,synthesized from tetraethyl orthosilicate(TEOS)and KH-560 via sol-gel method,was employed to functionalize the surface of GFs(Si-GFs).Together with a spherical boron nitride(BNN-30),the thermally conductive BNN-30/Si-GFs/epoxy laminated composites were then fabricated.Results demonstrate that Si-sol is beneficial to the improvement of mechanical properties for epoxy laminated composites(especially for ILSS).The BNN-30/Si-GFs/epoxy laminated composites with 15 wt%BNN-30 fillers display the optimal comprehensive properties.In-planeλ(λ//)andλ⊥reach the maximum of 2.37 and 1.07 W.m-1.K-1,146.9%and 132.6%higher than those of SiGFs/epoxy laminated composites(λ//=0.96 W.m-1.K-1 andλ⊥=0.46 W.m-1K-1),respectively,and also about 10.8 and 4.9 times those of pure epoxy resin(λ//=λ⊥,0.22 W.m-1.K-1).And the heat-resistance index(THRI),dielectric constant(ε),dielectric loss(tanδ),breakdown strength(E0),surface resistivity(ρs)as well as volume resistivity(ρv)are 197.3℃,4.95,0.0046,22.3 kV.mm-1,1.8×1014Ω,and 2.1×1014Ω.cm,respectively.

关键词： Thermally conductive composites Glass fibers Epoxy resin Silica-sol Surface functionalization