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Multiplicity and uniqueness of Positive Solutions for nonhomogeneous Semilinear Elliptic Equation with Critical Exponent

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Acta Mathematicae Applicatae Sinica 2016年第1期32卷 81-94页

作者： na ba Yan-yan WAng Lie ZHEng School of Science Hubei University of Technology Department of Mathematics Zhoukou Normal University

In this paper,we consider the following problem {-Δu（x）＋u（x）=λ（u^p（x）＋h（x））,x∈R^n,u（x）∈h^1（R^n）,u（x）〉0,x∈R^n,（＊）where λ 〉 0 is a parameter,p =（n＋2）/（n—2）.We will prove that there exists a positive constant 0 〈 A＊〈＋00such that（＊） has a minimal positive solution for λ∈（0,λ＊）,no solution for λ 〉 λ＊,a unique solution for λ = λ＊.Furthermore,（＊） possesses at least two positive solutions when λ∈（0,λ＊） and 3 ≤ n ≤ *** n ≥ 6,under some monotonicity conditions of h we show that there exists a constant 0 〈λ＊＊〈 λ＊ such that problem（＊）possesses a unique solution for λ∈（0,λ＊＊）.

关键词： nonhomogeneous semilinear elliptic problems multiplicity uniqueness

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不同粒色大麦萌发期抗旱性鉴定

分子植物育种 2024年第8期22卷 2648-2655页

作者：邓贵仲代欢程田田彭玉琳旦巴昌西西藏农牧学院植物科学学院林芝860000

为考察大麦种子颜色与抗旱性的相关性,本研究以16份有色大麦为材料,通过测定正常和15%PEg胁迫下的发芽势、发芽率、萌发活力指数、发芽指数、苗长、根长和种皮颜色指标Y (颜色亮度)和u (颜色浓度)值,利用相关性分析、主成分分析和聚类... 详细信息

为考察大麦种子颜色与抗旱性的相关性,本研究以16份有色大麦为材料,通过测定正常和15%PEg胁迫下的发芽势、发芽率、萌发活力指数、发芽指数、苗长、根长和种皮颜色指标Y (颜色亮度)和u (颜色浓度)值,利用相关性分析、主成分分析和聚类分析等方法进行抗旱性综合比较。结果表明,发芽势和萌发活力指数对干旱胁迫最敏感,根长和芽长的变化量最小;种皮颜色亮度与抗旱性综合F值呈负相关关系,颜色浓度与综合抗旱性F值呈正相关关系;综合各指标信息分析表明:16份材料呈现出籽粒颜色越浓、越亮抗旱性越强的趋势;深色大麦萌发期抗旱性大于浅色大麦;发现强耐旱性材料包括‘黄青稞’和‘乌西金青稞’,中度抗旱的材料包括‘普巴村农家种’和‘琼结野生大麦’,抗旱性相对最弱的材料为‘康青3号’、‘紫青稞’、‘日喀则17’等共12份。本研究将为有色大麦抗逆性研究提供最新理论参考。

关键词：有色大麦 PEg-6000 耐旱性综合排序

Characterizing robustness and sensitivity of convolutional neural networks for quantitative analysis of mitochondrial morphology

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Frontiers of Electrical and Electronic Engineering in China 2018年第4期6卷 344-358页

作者： Xiaoqi Chai Qinle ba ge Yang Department of Biomedical Engineering Carnegie Mellon UniversityPittsburghPA 15213USA Department of Computational Biology Carnegie Mellon UniversityPittsburghPA 15213USA

Quantitative analysis of mitochondrial morphology plays important roles in studies of mitochondrial biology. The analysis depends critically on segmentation of mitochondria, the image analysis process of extracting mitochondrial morphology from images. The main goal of this study is to characterize the performance of convolutional neural networks (Cnns) in segmentation of mitochondria from fluorescence microscopy images. Recently, Cnns have achieved remarkable success in challenging image segmentation tasks in several disciplines. So far, however, our knowledge of their performance in segmenting biological images remains limited. In particular, we know little about their robustness, which defines their capability of segmenting biological images of different conditions, and their sensitivity, which defines their capability of detecting subtle morphological changes of biological objects. We have developed a method that uses realistic synthetic images of different conditions to characterize the robustness and sensitivity of Cnns in segmentation of mitochondria. using this method, we compared performance of two widely adopted Cnns: the fully convolutional network (FCn) and the u-net. We further compared the two networks against the adaptive active-mask (AAM) algorithm, a representative of high-performance conventional segmentation algorithms. The FCn and the u-net consistently outperformed the AAM in accuracy, robustness, and sensitivity, often by a significant margin. The u-net provided overall the best performance. Our study demonstrates superior performance of the u-net and the FCn in segmentation of mitochondria. It also provides quantitative measurements of the robustness and sensitivity of these networks that are essential to their applications in quantitative analysis of mitochondrial morphology.

关键词： convolutional neural network mitochondrial morphology image segmentation robustness sensitivity

基于高光谱的退化高寒草甸土壤碳氮磷含量反演研究

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中国土壤与肥料 2024年第6期 241-251页

作者：柴瑜李希来马盼盼徐文印段成伟把熠晨青海大学农牧学院青海西宁810016

以黄河源区为研究区域,选取退化高寒草甸作为研究样地,通过野外调查采样,结合室内土壤养分与土壤高光谱数据测量,分析退化高寒草甸土壤植被及养分特征,对土壤高光谱数据进行数学变换与土壤养分含量相关系数计算,采用偏最小二乘回归(PLSR... 详细信息

以黄河源区为研究区域,选取退化高寒草甸作为研究样地,通过野外调查采样,结合室内土壤养分与土壤高光谱数据测量,分析退化高寒草甸土壤植被及养分特征,对土壤高光谱数据进行数学变换与土壤养分含量相关系数计算,采用偏最小二乘回归(PLSR)和反向传播神经网络(BPnn)方法分别建立土壤有机碳、全氮、全磷含量的反演模型。结果表明:PLSR建立的土壤有机碳和土壤全磷含量预测模型优于BPnn模型,预测效果更好,其中,土壤有机碳含量PLSR预测模型建模集R^(2)=0.9585,RMSE=0.1079,验证集R^(2)=0.9493,RMSE=0.1210,模型精度较高,可以进行准确估算,土壤全磷含量PLSR预测模型建模集R^(2)=0.7497,RMSE=0.2391,验证集R^(2)=0.5977,RMSE=0.2445,达到基本估算要求;BPnn建立的土壤全氮含量预测模型优于PLSR模型,其建模集R^(2)=0.8772,RMSE=0.7663,验证集R^(2)=0.6887,RMSE=0.8556,模型精度较好,达到基本估算要求。

关键词：黄河源区退化高寒草甸土壤碳氮磷高光谱遥感反演模型

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高寒草甸斑块化空间分异性及其地形因子影响

草地学报 2024年第2期32卷 570-578页

作者：王祎明李国荣李希来把熠晨王克钰姚文治张静青海大学地质工程系青海西宁810016 青海大学农牧学院青海西宁810016

青藏高原高寒草甸在国家生态环境保护战略中占据重要位置,近几十年来,气候变化和人为因素导致大面积高寒草甸发生斑块化退化。为探究高寒草甸斑块化空间分异性及各斑块类型间(裸地斑块、短期恢复斑块和长期恢复斑块)的分布规律以及其地... 详细信息

青藏高原高寒草甸在国家生态环境保护战略中占据重要位置,近几十年来,气候变化和人为因素导致大面积高寒草甸发生斑块化退化。为探究高寒草甸斑块化空间分异性及各斑块类型间(裸地斑块、短期恢复斑块和长期恢复斑块)的分布规律以及其地形因子的影响,本研究通过3S(RS,gIS,gnSS)技术获取位于青海省河南县和玛多县4个典型研究区的斑块类型分布及地形因子数据,利用景观生态指数探究不同斑块的空间分布差异。结果表明,研究区植被覆盖度随着海拔升高呈现先增加后减小的趋势,斑块景观的破碎化程度呈现先减小后增大的趋势。不同海拔地区斑块化程度最高的斑块类型都是长期恢复斑块。地形因子显著影响着不同斑块的分布,长期恢复斑块和健康草甸主要分布在阳坡平缓区域。

关键词：斑块化植被覆盖度景观格局地形因子空间差异

Microstructure design of C/C composites through electrochemical corrosion for brazing to nb

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Journal of Materials Science & Technology 2022年第9期104卷 33-40页

作者： Jin ba Xu Ji Bin Wang Peixin Li Jinghuang Lin Jian Cao Junlei Qi State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

Surface structure of C/C composites has been regulated through electrochemical corrosion at room temperature to modify the residual stress and improve the joining strength when brazed to *** unique crevice corrosion in C/C composites is investigated to reveal the change of corrosion depth and fiber *** interlacing zone of carbon fiber reinforced brazing alloy replaces the reaction layer in the original *** area is increased dramatically and the continuous crack will be *** interlacing zone eliminates the stress concentration and relieves the residual stress through reducing the property *** advantages contribute to the joining quality of C/C–*** strength of C/C–nb joint with 80μm depth reached 37.7 MPa,which was 1.2 times higher than that of original *** structure design of C/C composites not only expands the application in structure component,but also exhibits the promising application in energy field.

关键词： Thermal corrosion Electrochemical corrosion C/SiC composites Braze

肝硬化失代偿期继发肝性脑病的危险因素及预后分析

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临床和实验医学杂志 2024年第1期23卷 9-12页

作者：胡向党巴晓彤朱萍北京市大兴区人民医院急诊内科北京102600

目的分析肝硬化失代偿期(DLC)继发肝性脑病的危险因素及预后。方法回顾性选择2019年1月至2022年1月在北京市大兴区人民医院诊治的131例DLC患者作为研究对象,根据患者是否继发肝性脑病分为肝硬化失代偿期组(DLC组)和DLC继发肝性脑病组(DL... 详细信息

目的分析肝硬化失代偿期(DLC)继发肝性脑病的危险因素及预后。方法回顾性选择2019年1月至2022年1月在北京市大兴区人民医院诊治的131例DLC患者作为研究对象,根据患者是否继发肝性脑病分为肝硬化失代偿期组(DLC组)和DLC继发肝性脑病组(DLC+HEC组)。分析并比较DLC组和DLC+HEC组患者临床资料的差异。单因素和多因素Logistics回归分析DLC继发肝性脑病的危险因素。采用受试者工作特征(ROC)曲线分析预测DLC继发肝性脑病1年死亡的敏感度及特异度。结果DLC+HEC组患者的年龄、住院时间、ALT、AST、TBIL、APACHEⅡ评分、Child-Pugh分级C级比例及血氨分别为(64.5±8.2)岁、(18.7±2.6)d、(98.1±8.5)u/L、(82.4±7.3)u/L、(23.9±3.2)分、60.00%、(72.1±8.3)μmol/L,均显著高于DLC组[(57.4±7.5)岁、(11.5±1.8)d、(71.4±7.2)u/L、(67.1±6.6)u/L、(17.3±3.5)分、18.60%、(54.4±6.9)μmol/L],差异均有统计学意义(Pgistics回归分析发现患者年龄、ALT、AST、TBIL、APACHEⅡ评分、Child-Pugh分级及血氨与肝DLC继发肝性脑病风险显著相关(Pgistics回归分析发现年龄、APACHEⅡ评分、Child-Pugh分级及血氨为DLC继发肝性脑病的独立危险因素(Pugh分级预测DLC肝性脑病1年死亡截断值C级,敏感度为0.782,特异度为0.824;血氨预测DLC肝性脑病1年死亡截断值为75.3μmol/L,敏感度为0.855,特异度为0.863。结论年龄、APACHEⅡ评分、Child-Pugh分级及血氨为DLC继发肝性脑病的独立危险因素,且与患者预后相关。年龄≥66.7岁、APACHEⅡ评分≥24.5分、Child-Pugh分级C级及血氨≥75.3μmol/L提示预后不良。

关键词：肝硬化失代偿期肝性脑病危险因素预后

商品有机肥对不同坡向退化高寒草甸土壤特性的影响

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草地学报 2024年第8期32卷 2638-2647页

作者：徐文印马昀峤柴瑜段成伟把熠晨张静李希来青海大学农牧学院青海西宁810016 嘉峪关市林业和草原局甘肃嘉峪关735100

为研究有机肥施用量对黄河源区斑块化退化高寒草甸土壤特征的影响,我们在青海省河南蒙古族自治县多松乡阳坡和阴坡样地的斑块化退化高寒草甸,分别设置0 g·m^(-2)(CK),150 g·m^(-2)(M 1),450 g·m^(-2)(M 2),750 g·m^(-2)(M 3),1050 g... 详细信息

为研究有机肥施用量对黄河源区斑块化退化高寒草甸土壤特征的影响,我们在青海省河南蒙古族自治县多松乡阳坡和阴坡样地的斑块化退化高寒草甸,分别设置0 g·m^(-2)(CK),150 g·m^(-2)(M 1),450 g·m^(-2)(M 2),750 g·m^(-2)(M 3),1050 g·m^(-2)(M 4),1350 g·m^(-2)(M 5)6个商品有机肥施用量梯度,测定土壤养分、微生物生物量、酶活性以及微生物多样性的变化特征。结果显示:阳坡退化高寒草甸土壤呈弱碱性,有机肥不同处理下的土壤理化性质无显著变化。阴坡退化高寒草甸土壤pH值呈中性,土壤有机碳、土壤全氮和土壤全磷含量M 4处理较CK处理显著提高。在试验样地中土壤微生物生物量碳、氮、磷含量在有机肥不同施用量下无显著变化。阳坡样地土壤β-1,4-葡萄糖苷酶在M 5处理下达到最大值。通过灰色关联度综合分析得出在阳坡样地最佳商品有机肥施用量为450 g·m^(-2),阴坡样地有机肥最佳施用量为1050 g·m^(-2),该用量在恢复斑块化退化高寒草甸土壤理化性质、酶活性和微生物多样性方面具有明显的效果。

关键词：有机肥高寒草甸土壤理化性质土壤微生物生物量土壤酶活性微生物多样性灰色关联度

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Pathological and immunohistochemical findings of lungs,heart,liver,and kidneys,and unexpected findings of fungi and parasites in lungs of deceased COVID-19 patients:A case series

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Journal of Acute Disease 2023年第5期12卷 204-212,I0001-I0003页

作者： Mehmet n.Yakar Bişar Ergün Aylin Erol Özde gökbayrak TekincanÇ.Aktaş Özlem ulusan bağcı Fırat bayraktar Eyüp S.uçan Begüm Ergan Bilgin Cömert Ayşe Caner Safiye Aktaş Ali n.gökmen Division of Intensive Care Department of Anaesthesiology and ReanimationFaculty of MedicineDokuz Eylül UniversityİzmirTurkey Division of Intensive Care Department of Internal MedicineFaculty of MedicineDokuz Eylül UniversityİzmirTurkey Department of basic Oncology Institute of OncologyDokuz Eylül UniversityİzmirTurkey Department of basic Oncology Institute of Health SciencesEge UniversityİzmirTurkey Department of Parasitology Faculty of MedicineEge UniversityİzmirTurkey Division of Endocrinology and Metabolic Diseases Department of Internal MedicineFaculty of MedicineDokuz Eylül UniversityİzmirTurkey Department of Chest Diseases Faculty of MedicineDokuz Eylül UniversityİzmirTurkey

Objective:To define histopathologic and immunohistochemical features of the lungs,heart,liver,and kidneys in patients who died from coronavirus disease 2019(COVID-19),and to determine the presence of SARS-CoV-2 in all tissues,as well as the presence of fungi and parasites in lung ***:This retrospective case study was conducted in the intensive care units of Dokuz Eylül university Hospital,and patients(≥18 years)who died due to COVID-19 between October 2020 and April 2021 were *** biopsy samples of the patient’s lung,heart,liver,and kidney tissues were ***:In the study,we enrolled 12 patients(mean age:70 years;50%male).Alveolar epithelial cell damage and diffuse alveolar damage were predominant in lung *** lymphocyte infiltration,centrilobular sinusoidal dilatation,and microvesicular steatosis in the liver,together with pigmented cast,non-isometric vacuolar degeneration,and capillary plugging in the kidneys,were commonly found among the ***-CoV-2 nucleocapsid protein antibodies were detected in three lung and two kidney tissues,and so did angiotensin-converting enzyme 2 receptor positivity in one lung and more than half of the kidney *** RT-PCR tests were positive in three lungs and one kidney *** DnA isolation from lung tissues,Pneumocystis jirovecii was detected in nine patients,Aspergillus fumigatus in two,Microsporidia in three,and Cryptosporidium in ***:SARS-CoV-2 is a multisystemic *** and parasites should be investigated in critically ill COVID-19 patients prescribed corticosteroids.

关键词： Biopsy COVID-19 Histopathology Immunohisto-chemistry Opportunistic infections SARS-CoV-2