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Urbanization reduces resource use efficiency of phytoplankton community by altering the environment and decreasing biodiversity

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Journal of Environmental Sciences 2022年第2期34卷 140-151页

作者： yigang yang Huihuang Chen Mamun Abdullah Al Jean Claude Ndayishimiye Jun R yang Alain Isabwe Anqi Luo Jun yang Aquatic EcoHealth Group Fujian Key Laboratory of Watershed EcologyKey Laboratory of Urban Environment and HealthInstitute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Engineering Research Center of Ecology and Agricultural Use of Wetland(Ministry of Education) College of AgricultureYangtze UniversityJingzhou 434025China

Urbanization often exerts multiple effects on aquatic and terrestrial organisms,including changes in biodiversity,species composition and ecosystem ***,the impacts of urbanization on river phytoplankton in subtropical urbanizing watersheds remain largely ***,we explored the effects of urbanization on phytoplankton community structure(i.e.,biomass,community composition and diversity)and function(i.e.,resource use efficiency)in a subtropical river at watershed scale in southeast China over 6 years.A total of 318 phytoplankton species belonging into 120 genera and 7 phyla were identified from 108 *** biomass showed an increasing trend with increasing urbanization *** phytoplankton community shifted from Chlorophyta dominance in rural upstream waters to Bacillariophyta dominance in urbanized downstream ***,phytoplankton diversity and resource use efficiency(RUE=phytoplankton biomass/total phosphorus)were significantly decreased with increasing urbanization level from upstream to *** RUE exhibited a significant positive correlation with species richness,but a negative correlation with phytoplankton *** variation in environmental factors(turbidity,total nitrogen,NH_(4)^(+)-N,total phosphorus,PO_(4)^(3-)-P and percentage urbanized area)was significantly correlated with phytoplankton diversity and ***,our results revealed the influence of urbanization on phytoplankton community structure and ecosystem function was due to its altering the environmental ***,human-driven urbanization may play crucial roles in shaping the structure and function of phytoplankton communities in subtropical rivers,and the mechanism of this process can provide important information for freshwater sustainable uses,watershed management and conservation.

关键词： Plankton Community functioning Subtropical river Urbanization gradient Land use Watershed ecology

Djrho2 is involved in regeneration of visual nerves in Dugesia japonica

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Journal of Genetics and Genomics 2010年第11期37卷 713-723页

作者： Changxin Ma yang Gao Guoliang Chai Hanxia Su Niejun Wang yigang yang Chunbo Li Di Miao Wei Wu Protein Science Laboratory of the Ministry of Education School of Life Sciences Tsinghua University Beijing 100084 China School of Medicine Nankai University Tianjin 300071 China Department of Engineering Physics Ministry of Education Key Laboratory of Particle & Radiation Imaging Tsinghua University Beijing 100084 China Center of Biomedical Analysis Tsinghua University Beijing 100084 China

The freshwater planarian is a powerful animal model for studying regeneration and stem cell activity in vivo. During regeneration, stem cells （neoblasts in planarian） migrated to the wounding edge to re-build missing parts of the body. However, proteins involved in regulating cell migration during planarian regeneration have not been studied extensively. Here we report two small GTPase genes （Djrho2 and Djrho3） of Dugesiajaponica （strain Pek-1）. In situ hybridization results indicated that Djrho2 was expressed throughout the body with the exception of thc pharynx region while Djrho3 was specifically expressed along the gastro-vascular system. Djrho2 was largely expressed in neoblasts since its expression was sensitive to X-ray irradiation. In Djrho2-RNAi planarians, smaller anterior blastemas were observed in tail fragments during regeneration. Consistently, defective regeneration of visual nerve was detected by immunostairming with VC-1 antibody. These results suggested that Djrho2 is required for proper anterior regeneration in planairan. In contrast, no abnormality was observed after RNAi of Djrho3. We compared protein compositions of control and Djrho2-RNAi planarians using an optimized proteomic approach. Twenty-two up-regulated and 26 de-regulated protein spots were observed in the two-dimensional elec- trophoresis gels, and 17 proteins were successfully identified by Mass Spectrometry （MS） analysis. Among them, 6 actin-binding or cytoskeleton-related proteins were found de-expressed in Djrho2-RNAi animals, suggesting that abnormal cytoskeleton assembling and cell migration were likely reasons of defected regeneration.

关键词： planar/an Dugesiajaponica RNAi Rho GTPase proteomics

Monte-Carlo simulation of cement neutron field distribution characteristics in PGNAA

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Nuclear Science and Techniques 2012年第6期23卷 337-343页

作者： yang Jianbo yang yigang LI Yuanjing TUO Xianguo LI Zhe LIU Mingzhe CHENG Yi MU Keliang WANG Lei Department of Engineering Physics Tsinghua University Chengdu University of Technology State Key Laboratory of Geohazard prevention & Geoenvironment Protection Nuclear Power Institute of China

The distribution characteristics of the neutron field in cement was simulated using the MCNP code to comply with the requirements of an online Prompt Gamma Neutron Activation Analysis *** results showed that the neutron relative flux proportion reduced with increasing cement *** the cement thickness remains unchanged,the reduced proportion of thermal neutrons increases to a small extent,but the epithermal, intermediate,and fast neutrons will decrease according to the geometric progression.H element in the cement mainly affects the reduction of fast neutrons and other single-substance elements,e.g.,O,Ca,56Fe,Si,and *** also slows down the reduction of the fast neutrons via inelastic scattering.O contributes more than other elements in the reduction of fast *** the H content affects the thermal,epithermal,intermediate,and fast neutrons, while changing the Ca,Fe,and Si contents only influences the thermal,epithermal,and intermediate neutrons;hence, there is little effect on the reduction of fast neutrons.

关键词：蒙特卡罗模拟中子活化 PGNAA 水泥特征场分布在线分析系统 MCNP程序

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光中子爆炸物成像的一种还原方法

核技术 2012年第1期35卷 31-36页

作者：羊奕伟杨祎罡辐射物理及探测实验室清华大学工程物理系北京100084 粒子技术与辐射成像教育部重点实验室北京100084

针对光中子成像中的模糊图像还原问题,研究了模糊来源,建立了一种物理数学模型。在此基础上,分别使用非约束条件下以及约束条件下的迭代算法,对数学模型进行求解。模拟及实验数据反解结果表明,约束条件下的反解算法能有效地消除成像中... 详细信息

针对光中子成像中的模糊图像还原问题,研究了模糊来源,建立了一种物理数学模型。在此基础上,分别使用非约束条件下以及约束条件下的迭代算法,对数学模型进行求解。模拟及实验数据反解结果表明,约束条件下的反解算法能有效地消除成像中的模糊重叠现象,有利于更加清晰准确地判断被探测物的性质。

关键词：中子成像反解算法

Mixed-Oligosaccharides Promote Seedling Growth of Direct-Seeded Rice under Salt and Alkaline Stress

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Rice science 2024年第6期31卷 712-724,I0016-I0022页

作者： yang yigang XU Ya’nan BAI Yeran ZHANG Yuanpei HAN Wei Makoto SAITO LÜGuohua SONG Jiqing BAI Wenbo Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China Institute of Crop Research Ningxia Academy of Agriculture and Forestry SciencesYinchuan 750002China Shandong General Station of Agricultural Technology Extension Ji’nan 250100China Resonac Corporation(Showa Denko K.K.) Tokyo 105-8518Japan China National Rice Research Institute Hangzhou 311400China

Rice direct seeding technology is an appealing alternative to traditional transplanting because it conserves labor and irrigation ***,there are two main issues,salt stress and alkaline stress,which contribute to poor emergence and seedling growth,thereby preventing the widespread adoption and application of this technique in the Ningxia Region of ***,to determine whether germination can be promoted by mixed-oligosaccharide(KP)priming(in which seeds are soaked in a KP solution before sowing)under salt and alkaline stress,a proteomics study was ***-priming significantly mitigated abiotic stress,such as salt and alkaline stress,by inhibiting root elongation,ultimately improving seedling *** comparing the proteomics analyses,we found that energy metabolic pathway was a vital factor in KP-priming,which explains the alleviation of salt and alkaline *** proteins involved in starch mobilization,pyruvate mobilization,and ATP synthesis,were up-regulated by KP-priming,significantly blocking salt and alkaline-triggered starch accumulation while enhancing pyruvate ***-priming also up-regulated ATP synthase to improve energy efficiency,thereby improving ATP *** addition,it enhanced antioxidant enzymatic activities and reduced the accumulation of reactive oxygen *** of these factors contributed to a better understanding of the energy regulatory pathway enhanced by KP-priming,which mediated the promotion of growth under salt and alkaline ***,this study demonstrated that KP-priming can improve rice seed germination under salt and alkaline stress by altering energy metabolism.

关键词： rice salt and alkaline stress mixed-oligosaccharide metabolic adjustment starch mobilization seed priming

A Lightweight Multiscale Feature Fusion Network for Solar Cell Defect Detection

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Computers, Materials & Continua 2025年第1期82卷 521-542页

作者： Xiaoyun Chen Lanyao Zhang Xiaoling Chen yigang Cen Linna Zhang Fugui Zhang School of Mechanical Engineering Guizhou UniversityGuiyang550025China School of Computer Science and Technology Beijing Jiaotong UniversityBeijing100044China

Solar cell defect detection is crucial for quality inspection in photovoltaic power generation *** the production process,defect samples occur infrequently and exhibit random shapes and sizes,which makes it challenging to collect defective ***,the complex surface background of polysilicon cell wafers complicates the accurate identification and localization of defective *** paper proposes a novel Lightweight Multiscale Feature Fusion network(LMFF)to address these *** network comprises a feature extraction network,a multi-scale feature fusion module(MFF),and a segmentation ***,a feature extraction network is proposed to obtain multi-scale feature outputs,and a multi-scale feature fusion module(MFF)is used to fuse multi-scale feature information *** order to capture finer-grained multi-scale information from the fusion features,we propose a multi-scale attention module(MSA)in the segmentation network to enhance the network’s ability for small target ***,depthwise separable convolutions are introduced to construct depthwise separable residual blocks(DSR)to reduce the model’s parameter ***,to validate the proposed method’s defect segmentation and localization performance,we constructed three solar cell defect detection datasets:SolarCells,SolarCells-S,and *** and SolarCells-S are monocrystalline silicon datasets,and PVEL-S is a polycrystalline silicon *** results show that the IOU of our method on these three datasets can reach 68.5%,51.0%,and 92.7%,respectively,and the F1-Score can reach 81.3%,67.5%,and 96.2%,respectively,which surpasses other commonly usedmethods and verifies the effectiveness of our LMFF network.

关键词： Defect segmentation multi-scale feature fusion multi-scale attention depthwise separable residual block

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高层建筑物地基沉降测量及有效控制方法研究

中国测试 2021年第6期47卷 95-100页

作者：杨义刚罗伟兵江西财经职业学院江西九江332000 华东交通大学江西南昌330013

为提高对建筑地基沉降计算的准确性并有效控制地基沉降,提出基于Duncan-Chang本构模型的高层建筑物地基沉降测量及有效控制方法。利用建筑传感器节点分布模块、传感网络模块、通信模块、上位机监测模块构建建筑地基沉降监测系统,采集地... 详细信息

为提高对建筑地基沉降计算的准确性并有效控制地基沉降,提出基于Duncan-Chang本构模型的高层建筑物地基沉降测量及有效控制方法。利用建筑传感器节点分布模块、传感网络模块、通信模块、上位机监测模块构建建筑地基沉降监测系统,采集地基沉降信息数据并对异常情况进行实时报警;利用上述采集到的建筑沉降数据,引入Duncan-Chang本构模型,结合分层总和法计算高层建筑物地基沉降量。在此基础上,分别从强化建筑框架整体刚度、积极开展沉降监测、选用科学施工方案三方面给出沉降控制对策。实验结果表明所提方法的测量结果与实际值拟合度较高,证明该方法具有较强的实用性,能够有效控制高层建筑物地基沉降。

关键词：高层建筑物地基沉降沉降量测量 Duncan-Chang本构模型沉降控制

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遵循工程逻辑构建一体化的课程体系

高等工程教育研究 2019年第1期67卷 44-51页

作者：杨毅刚唐浩宋庆北京邮电大学北京邮电大学经济管理学院

回归工程,服务社会,对接工程实际,满足工程需求,是工程教育改革的出发点和落脚点。工程教育要做到适应、支撑和引领新经济、新技术、新产业、新业态和新模式发展,应按照工程逻辑组织教学活动,培养学生遵循工程逻辑解决复杂工程问题的能... 详细信息

回归工程,服务社会,对接工程实际,满足工程需求,是工程教育改革的出发点和落脚点。工程教育要做到适应、支撑和引领新经济、新技术、新产业、新业态和新模式发展,应按照工程逻辑组织教学活动,培养学生遵循工程逻辑解决复杂工程问题的能力。本文从企业的视角出发,深入剖析了企业设计/开发解决方案的内在规律和逻辑,明确了全周期、全流程工程逻辑的内涵和要求,分析了《华盛顿协议》与工程逻辑的关系,提出通过一体化的课程体系来体现工程逻辑,并给出了构建一体化课程体系的一整套课程设计理念、设计方法论和实施措施的建议。

关键词：工程逻辑工程教育改革新工科复杂工程问题课程体系 IPD

工程教育专业认证与CDIO模式异同分析与相互借鉴

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高等工程教育研究 2018年第5期66卷 45-51页

作者：杨毅刚宋庆唐浩北京邮电大学北京邮电大学经济管理学院

第四次工业革命的时代背景下,新产业、新业态、新技术和新模式层出不穷,并进一步加速新经济的发展,而新经济发展离不开高质量的工程科技人才队伍的有效支撑,作为培养工程科技人才的源头,工程教育如何培养支撑和引领新经济和新兴产业发... 详细信息

第四次工业革命的时代背景下,新产业、新业态、新技术和新模式层出不穷,并进一步加速新经济的发展,而新经济发展离不开高质量的工程科技人才队伍的有效支撑,作为培养工程科技人才的源头,工程教育如何培养支撑和引领新经济和新兴产业发展的人才受到社会各界的广泛重视。同时,各类高校对工程教育的重视程度也是日渐高涨,专业认证和CDIO模式作为全球公认的两大主流工程教育阵营,各类高校为有效提升工程教育水平在两者之间如何做选择?本文将从两者的发展愿景、价值理念、目标、实施思路、实施方案、评估评价体系和改进体系等多个方面进行比较分析,深挖两者的相同点和不同点,并揭示造成这些异同点的根本原因——定位差异,最后着眼工程教育发展趋势,提出专业认证和CDIO模式如何相互借鉴的关键点,以期为高校深化工程教育改革提供新思路。

关键词：工程教育改革工程教育专业认证 CDIO 华盛顿协议