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塔额盆地草原蝗虫空间生态位研究

环境昆虫学报 2024年第3期46卷 625-634页

作者：宋占云万育欣查绪栋陈冉杨静 ROMAN Jashenko 季荣新疆师范大学生命科学学院新疆特殊环境物种保护与调控生物学实验室中亚区域跨境有害生物联合控制国际研究中心乌鲁木齐830054 哈萨克斯坦科学院动物研究所阿拉木图050038

本文分析塔额盆地草原蝗虫的生态位,旨在为当地的蝗灾监控、治理及生态平衡保护提供理论依据。本研究对塔额盆地冲积平原、山前洪积倾斜平原、山地3种地形的草原蝗虫的空间生态位进行分析,统计得出了蝗虫优势度、群落组成差异、Levins... 详细信息

本文分析塔额盆地草原蝗虫的生态位,旨在为当地的蝗灾监控、治理及生态平衡保护提供理论依据。本研究对塔额盆地冲积平原、山前洪积倾斜平原、山地3种地形的草原蝗虫的空间生态位进行分析,统计得出了蝗虫优势度、群落组成差异、Levins生态位宽度和Shannon生态位宽度、Pianka生态位重叠等相关参数。结果表明:3种地形共采集蝗虫6科19种1023头,不同地形优势种、常见种及稀有种均存在差异。山地与山前洪积倾斜平原、冲积平原的蝗虫群落组成差异较大。黑条小车蝗Oedaleus decorus decorus、蓝胫戟纹蝗Dociostaurus tartarus、意大利蝗Calliptamus italicus、红胫戟纹蝗Dociostaurus kraussi kraussi、伪星翅蝗Calliptamus coelesyriensis的生态位较宽且与其他蝗虫存在生态位重叠。塔额盆地草原蝗虫发生种类较多,绝大部分优势种蝗虫对空间资源的利用能力较强、竞争较激烈,对优势危害种加大监测力度,而针对山前洪积倾斜平原中的稀有种类,应加以保护以确保生物多样性。

关键词：塔额盆地生态位宽度生态位重叠草原蝗虫

Tautening effect mechanism of titanium-alloy InterTAN nail

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Rare Metals 2023年第12期42卷 4226-4233页

作者： Xiang-Sheng Gao Sheng-Kai Ma Wang-Ao-ran chen Min Wang Qi Pan Zi-Yu Liu Beijing Key Laboratory of Advanced Manufacturing Technology Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China The Fourth People's Hospital of Jinan Jinan 250031China School of Engineering Medicine Beihang UniversityBeijing 100191China Division of Surgery&Interventional Science University College LondonRoyal National Orthopaedic HospitalLondon HA74LPUK

Although InterTAN(IT)nails are widely employed to treat femoral intertrochanteric fractures,the mechanism behind the tautening effect of titanium-alloy IT nails is not well *** study aimed to reveal the mechanism of this effect.A torque test experiment was conducted,with the torque value recorded and transformed to obtain the tautening ***,theoretical and finite element analyses were performed to further understand the *** influence of age and pitch-difference on the tautening effect was also examined in the study,the results attributed to the pitch-varying integrated interlocking lag *** torque and the corresponding tautening effect drastically increase as the screw is inserted deeper during the second stage,while the torque measured in the first stage is always ***,the tautening force increases with increasing age,this relationship helps evaluate the effect at different *** tautening effect also increases nearly linearly with the pitch difference,which can be adjusted during the IT design stage to select or design IT in engineering practice.

关键词： Tautening effect InterTAN nail Finite element analysis Torque

横江流域pH值时空变化特征与浮游植物关系研究

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环境科学与管理 2024年第5期49卷 107-112页

作者：汪伯伦陈然罗毅胡军钱丽萍黄山市生态环境执法监测站安徽黄山245041 黄山学院生命与环境科学学院安徽黄山245021

文章以横江流域pH值为研究对象,分析了pH值的时空变化特征,以及浮游植物群落对pH值的影响,探讨了pH值变化的影响因素以及内在的机理。研究结果表明:横江流域pH值从上游到下游逐渐升高的趋势,7、8月份pH值最高为9.1,4-6月份最低为7.5。影... 详细信息

文章以横江流域pH值为研究对象,分析了pH值的时空变化特征,以及浮游植物群落对pH值的影响,探讨了pH值变化的影响因素以及内在的机理。研究结果表明:横江流域pH值从上游到下游逐渐升高的趋势,7、8月份pH值最高为9.1,4-6月份最低为7.5。影响pH值变化主要因素是溶解氧、叶绿素a、水温。横江流域主要的浮游植物的种属7门60属,其中硅藻门最为丰富,优势种也是以硅藻门为主;春季以硅藻为主,夏季以蓝藻为主,秋季以绿藻、硅藻为主,可以看出浮游植物群落变化导致了水体pH值的季节性的变化,因此,生物作用是横江流域pH值变化的主要因素。

关键词：横江流域河流pH值浮游植物相关性研究

In-depth analysis of the genome of Trypanosoma evansi, an etiologic agent of surra

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Science China(Life Sciences) 2019年第3期62卷 406-419页

作者： Lili Zheng Ning Jiang Xiaoyu Sang Naiwen Zhang Kai Zhang Hongyu chen Na Yang Ying Feng ran chen Xun Suo Qijun chen Key Laboratory of Zoonosis College of Animal Science and Veterinary Medicine Shenyang Agricultural University Department of Food Science Shenyang Agricultural University Department of Parasitology College of Veterinary Medicine Chinese Agricultural University

Trypanosoma evansi is the causative agent of the animal trypanosomiasis surra, a disease with serious economic burden worldwide. The availability of the genome of its closely related parasite Trypanosoma brucei allows us to compare their genetic and evolutionarily shared and distinct biological features. The complete genomic sequence of the T. evansi YNB strain was obtained using a combination of genomic and transcriptomic sequencing, de novo assembly, and bioinformatic analysis. The genome size of the T. evansi YNB strain was 35.2 Mb, showing 96.59% similarity in sequence and 88.97% in scaffold alignment with T. brucei. A total of 8,617 protein-coding genes, accounting for 31% of the genome, were predicted. Approximately 1,641 alternative splicing events of 820 genes were identified, with a majority mediated by intron retention, which represented a major difference in post-transcriptional regulation between T. evansi and T. brucei. Disparities in gene copy number of the variant surface glycoprotein, expression site-associated genes, microRNAs, and RNA-binding protein were clearly observed between the two parasites. The results revealed the genomic determinants of T. evansi, which encoded specific biological characteristics that distinguished them from other related trypanosome species.

关键词： Trypanosoma trypanosomiasis genome annotation function

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矿用提升机钢丝绳换绳车同步齿轮特性分析

矿山机械 2024年第5期52卷 19-24页

作者：陈然李金龙张景亮邓海顺安徽理工大学机电工程学院安徽淮南232001

针对当前矿用提升钢丝绳换绳车出现的两链轮速度不同步引起的问题,提出在链轮轴上加装一对同步齿轮的方法,分析同步齿轮受到转矩波动时对其啮合特性的影响。首先,进行静强度分析,结合赫兹理论进行对比验证;然后,考虑液压马达输出转矩波... 详细信息

针对当前矿用提升钢丝绳换绳车出现的两链轮速度不同步引起的问题,提出在链轮轴上加装一对同步齿轮的方法,分析同步齿轮受到转矩波动时对其啮合特性的影响。首先,进行静强度分析,结合赫兹理论进行对比验证;然后,考虑液压马达输出转矩波动,设置3种不同的波动系数。结果表明:齿轮接触面所受接触压力随所受转矩变化而变化,转矩波动越大,齿轮面接触压力波动也越大;齿轮齿面与齿根面的最大等效应力变化趋势,基本与恒定转矩时的最大等效应力变化趋势一致,但是其最大等效应力的幅值,会随转矩波动的增大而变大。

关键词：钢丝绳换绳车同步齿轮转矩特性

多层卷积网络目标识别算法在烟丝宽度检测中的应用研究

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机械设计与制造工程 2024年第6期53卷 127-132页

作者：刘鑫谢真成关文锦陈然邝素琴广东中烟工业有限责任公司广州卷烟厂广东广州510385 广东中烟工业有限责任公司广东广州510385

为了提高烟丝宽度检测效率,提出一种多层卷积网络目标识别算法。该算法以YOLOv3为基础结构,通过添加特征层、注意力机制、空间金字塔结构、改进聚类函数和损失函数的方式,实现了对传统识别算法的改进优化。基于多层卷积网络目标识别算... 详细信息

为了提高烟丝宽度检测效率,提出一种多层卷积网络目标识别算法。该算法以YOLOv3为基础结构,通过添加特征层、注意力机制、空间金字塔结构、改进聚类函数和损失函数的方式,实现了对传统识别算法的改进优化。基于多层卷积网络目标识别算法构建烟丝宽度检测模型,通过获取图像中目标烟丝宽度,完成对烟丝宽度的精准检测。烟丝的主客观识别效果与宽度检测结果表明:该算法能够较好地保留烟丝轮廓细节,具有较强的识别能力和较高的检测精度,交并比、精准度、AUC分别达到了0.966、0.969、0.963,且检测最大误差为-0.073 mm,相对误差较低。实验结果证实该算法对烟丝宽度检测具有较高的实用价值,大大提高了检测精度。

关键词：烟丝宽度检测 YOLOv3 多层卷积网络目标识别翻转宽度算法

胎儿心脏定量分析技术对肺动脉狭窄及肺动脉闭锁胎儿心脏形态及功能的初步研究

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中华超声影像学杂志 2024年第6期33卷 489-496页

作者：张小敏赵博文潘美彭晓慧陈冉毛彦恺马明明田园诗张铭旋邓妍浙江大学医学院附属邵逸夫医院超声科、浙江省胎儿心脏超声诊断技术指导中心、浙江大学邵逸夫临床医学研究所杭州310016 浙江省杭州市临平区第一人民医院超声科杭州311100

目的应用胎儿心脏定量分析技术(fetal HQ)定量分析肺动脉狭窄(PS)和肺动脉闭锁(PA)胎儿心脏形态及左、右心室收缩功能,评估不同程度右心室流出道梗阻(RVOTO)对胎儿左、右心室收缩功能的影响,为构建一种胎儿PS及PA进展预测模型和临床决... 详细信息

目的应用胎儿心脏定量分析技术(fetal HQ)定量分析肺动脉狭窄(PS)和肺动脉闭锁(PA)胎儿心脏形态及左、右心室收缩功能,评估不同程度右心室流出道梗阻(RVOTO)对胎儿左、右心室收缩功能的影响,为构建一种胎儿PS及PA进展预测模型和临床决策工具进行早期的数据积累和参数探索。方法回顾性选取2020年7月至2021年12月在浙江大学医学院附属邵逸夫医院超声科行胎儿超声心动图检出的轻中度PS胎儿42例和重度PS或PA胎儿23例作为病例组,选取与其孕周相匹配的正常胎儿195例作为对照组,利用fetal HQ技术测量两组胎儿整体球形指数(GSI),左心室射血分数(LVEF),左、右心室面积变化率(LVFAC、RVFAC)和左、右心室纵向应变(LVGLS、RVGLS)以及左心室和右心室各自的24节段球形指数(SI)、短轴缩短率(FS),分析比较病例组与对照组及病例组内的差异。结果与对照组比较,病例组GSI、LVGLS、LVEF、LVFAC、RVGLS、RVFAC均减低,轻中度PS组差异有统计学意义(均P<0.05),重度PS/PA组差异有统计学意义(均P<0.01);轻中度PS组左心室第2节段、右心室第24节段SI和左心室第1~13节段、右心室第1~16节段、右心室第20~24节段FS与对照组比较差异有统计学意义(均P<0.05);重度PS/PA组右心室第1~22节段SI和左心室第6~13节段、左心室第21~24节段、右心室第1~14节段FS减低,与对照组比较差异有统计学意义(均P<0.05);重度PS/PA组RVGLS、RVFAC、右心室第1~17节段SI较轻中度PS组减低(均P<0.05)。结论初步研究结果显示fetal HQ提供的定量指标可以用于罹患PS/PA胎儿的心脏形态及功能的评估,为进一步深入了解此类胎儿的心脏形态与功能改变提供参考信息。

关键词：超声心动描记术胎儿心脏定量分析技术肺动脉狭窄肺动脉闭锁球形指数

Isolation of phloridzin-degrading,IAA-producing bacterium Ochrobactrum haematophilum and its effects on the apple replant soil environment

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Horticultural Plant Journal 2023年第2期9卷 199-208页

作者： Weitao Jiang ran chen Lei Zhao Yanan Duan Haiyan Wang Zhubing Yan Xiang Shen Xuesen chen chengmiao Yin Zhiquan Mao State Key Laboratory of Crop Biology College of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandongChina

We isolated and identified a bacterium that could produce IAA and degrade phloridzin in the rhizosphere soil of healthy replanted apple(the rootstock is M9T337 and the scion is Yanfu 3),providing a theoretical basis for reducing the obstacles associated with apple replant disease(ARD).Isolates were screened using Salkowski colorimetry and screening medium for *** isolate of interest(W6)was identified as Ochrobactrum haematophilum based on morphological analysis,physiological and biochemical tests,and 16S rDNA *** a laboratory experiment,W6 produced auxin and promoted the growth of Arabidopsis thaliana roots,and its degradation rate of 100 mg.L^(-1 )phloridzin was 62.0%.In a pot experiment,W6 significantly reduced the phenolic acid contents of replanted soil,lowered the abundance of the harmful fungus Fusarium solani,and increased soil enzyme activities,thereby improving the micro-ecological environment of replant soil.W6 increased the root antioxidant enzyme activity and leaf photosynthetic pigment content of replanted Malus hupehensis ***,effectively alleviating the decrease in net photosynthetic rate,transpiration rate and stomatal conductance caused by *** a field experiment,W6 also promoted the growth of replanted apple(the rootstock is M9T337 and the scion is Yanfu 3)***,W6 can promote apple growth and degrade phenolic acids,and it can be used as an effective treatment for the reduction of ARD.

关键词： Malus hupehensis Rehd. Apple Apple replant disease Ochrobactrum haematophilum Phloridzin Rhizosphere soil

The impact of D&O insurance on excess corporate leverage

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China Journal of Accounting Research 2022年第4期15卷 66-88页

作者： Jiamin Liu Yalin Jiang Shengdao Gan ran chen School of Economics and Management Hubei University of TechnologyWuhanChina School of Social Audit Nanjing Audit UniversityNanjingChina Business School Sichuan UniversityChengduChina Postdoctoral Research Workstation Anhui Rural Credit UnionHefeiChina

The governance effects of directors’and officers’liability insurance(D&O insurance),an important tool for risk diversification,are of strong concern in the capital *** a sample of Chinese A-share listed firms from2009 to 2018,we examine the impact of D&O insurance on excess corporate *** find that D&O insurance is negatively associated with excess corporate leverage and that this result is consistent with a series of robustness *** analyses show that D&O insurance impedes excess corporate leverage mainly because of its effect on external *** effect is more pronounced for firms that are state-owned,have political connections and are located in provinces with low marketization than for other firms.

关键词： D&O insurance Excess leverage Monitoring effect Government interventions