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基于深度学习方法荒漠草原典型植物花朵计数

环境生态学 2024年第2期6卷 1-8页

作者：王永财万华伟高吉喜胡卓玮首都师范大学资源环境与旅游学院北京100048 生态环境部卫星环境应用中心北京100094

草原植物花朵计数可以帮助我们了解草原植物的生长状况、繁殖能力、群落结构等信息,通过人工计数方法获取草原上不同物种花朵丰度是一个费时费力的过程。本研究基于深度学习目标检测方法,在鄂尔多斯荒漠草原上10个样地和50个样方上开展... 详细信息

草原植物花朵计数可以帮助我们了解草原植物的生长状况、繁殖能力、群落结构等信息,通过人工计数方法获取草原上不同物种花朵丰度是一个费时费力的过程。本研究基于深度学习目标检测方法,在鄂尔多斯荒漠草原上10个样地和50个样方上开展检测模型训练、评估和应用。从YOLOv7的3个模型整体表现来看,YOLOv7-E6E的F1-sorce和mAP@0.5均可达到0.7以上,具有较高的识别精度。从YOLOv7的3个模型在5种花朵检测的表现来看,YOLOv7-X、YOLOv7-E6E模型在北芸香、蒙古韭、细叶韭的检测上mAP@0.5高于0.8,而3个模型中仅有YOLOv7-E6E在蒺藜、兔唇花的mAP@0.5超过0.6。从模型在50个样方的花朵计数应用来看,YOLOv7-E6E模型花朵计数的总体正确率为0.91,能满足这5种草原开花植物检测和计数的需要。综上所述,通过深度学习花朵快速计数可以提高样方尺度花期植物调查效率,但为满足大规模物种调查和计数的任务需求,仍需扩大样本量和不断改进模型结构,以提高模型植物花朵检测的整体性能。

关键词：深度学习目标检测花朵计数草地植物

双腹板工字型GFRP腰梁机械连接力学性能试验研究

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科学技术与工程 2024年第4期24卷 1433-1439页

作者：郝增明王忠胜白晓宇章伟张鹏飞孙培富包希吉李明闫楠自然资源部滨海城市地下空间地质安全重点实验室青岛266000 青岛理工大学土木工程学院青岛266520 中建八局第二建设有限公司济南250014 青岛中建联合集团有限公司青岛266100 江苏海川新材料科技有限公司句容212400

为深入研究双腹板工字型玻璃纤维增强复合材料(glass fiber reinforced polymer,GFRP)腰梁机械连接节点的力学性能,基于无连接和有机械连接2种类型GFRP腰梁的静载试验,分析双腹板工字型GFRP腰梁在三分点对称加荷下的受力特征,明确2种类... 详细信息

为深入研究双腹板工字型玻璃纤维增强复合材料(glass fiber reinforced polymer,GFRP)腰梁机械连接节点的力学性能,基于无连接和有机械连接2种类型GFRP腰梁的静载试验,分析双腹板工字型GFRP腰梁在三分点对称加荷下的受力特征,明确2种类型腰梁的极限状态和破坏形式。结果表明:GFRP腰梁采用双腹板工字型截面型式,截面的最大应力为183 MPa,是GFRP腰梁纵向抗拉强度的62%,纵向抗压强度的73%(容许压缩承载力的205%),可以使GFRP材料强度得到充分发挥,腰梁稳定性能良好;GFRP腰梁容易出现局部破坏,首先在翼缘板处发生局部失稳,随即引起腹板产生屈曲破坏,翼缘和腹板连接处出现面层剥离和鼓起,腰梁连接处增设的缀板和螺栓可有效地抑制该局部破坏变形;采用螺栓机械连接并在连接处增设同材质缀板,可降低螺栓钻孔对梁体本身截面的削弱作用,使GFRP腰梁的刚度和极限承载能力分别提高17.9%和44.9%,是GFRP腰梁的合理连接方式。研究成果可为GFRP腰梁的推广应用提供参考和借鉴。

关键词：玻璃纤维增强复合材料(GFRP)腰梁机械连接静载试验力学性能破坏形式

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区域生态学基本理论探索

中国环境科学 2013年第7期33卷 1252-1262页

作者：高吉喜环境保护部南京环境科学研究所江苏南京210042

全球经济一体化、区域发展一体化,以及生态服务转移引发的区域生态问题越来越受到人们的关注,区域生态问题也直接影响到区域的可持续发展.因此,构建一门针对区域生态问题的系统学科成为当务之急.本文基于生态学、地理学、经济学及其它... 详细信息

全球经济一体化、区域发展一体化,以及生态服务转移引发的区域生态问题越来越受到人们的关注,区域生态问题也直接影响到区域的可持续发展.因此,构建一门针对区域生态问题的系统学科成为当务之急.本文基于生态学、地理学、经济学及其它相关学科理论,尝试从学科发展角度探讨建立区域生态学学科理论框架.文章提出区域生态学是研究区域生态结构、过程、功能,以及区域间生态要素耦合和相互作用机理的学科,生态介质是区域生态的联系纽带和核心要素.根据生态系统构成要素和当前人类活动,影响区域的突出生态介质有水、风和资源,通过这3种介质,分别形成流域、风域和资源圈3大类型生态区域.区域生态学的主要研究范畴和要点有:区域生态结构、过程与功能、区域生态完整性和生态分异规律、区域生态演变规律及其驱动力、区域生态承载力和生态适宜性、区域生态联系和生态资产流转,以及区域生态补偿和环境利益共享机制.

关键词：区域生态学学科理论研究范畴学科特点

Novel miRNA, miR-sc14, promotes Schwann cell proliferation and migration

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Neural Regeneration Research 2019年第9期14卷 1651-1656页

作者： xi-Meng ji Shan-Shan Wang xiao-Dong Cai xing-Hui Wang Qian-Yan Liu Pan Wang Zhang-Chun Cheng Tian-Mei Qian Key Laboratory of Neuroregeneration of jiangsu and Ministry of Education Co-innovation Center of NeuroregenerationNantong UniversityNantongJiangsu ProvinceChina Nonnasality Clinical Medicine Nanjing Medical UniversityNanjingJiangsu ProvinceChina Affiliated Hospital of Nantong University NantongJiangsu ProvinceChina

MicroRNAs refer to a class of endogenous,short non-coding RNAs that mediate numerous biological *** regulate various physiological and pathological activities of peripheral nerves,including peripheral nerve repair and ***,using a rat sciatic nerve injury model,we identified many functionally annotated novel microRNAs,including ***,we used real-time reverse transcription-polymerase chain reaction to examine miR-sc14 expression in rat sciatic nerve *** results show that miRsc14 is noticeably altered following sciatic nerve injury,being up-regulated at 1 day and diminished at 7 *** and transwell chamber assay results showed that miR-sc14 mimic promoted proliferation and migration of Schwann cells,while miR-sc14 inhiThe study was approved by the jiangsu Provincial Laboratory Animal Management Committee,China on March 4,2015(approval No.20150304-004).bitor suppressed their proliferation and ***,bioinformatic analysis examined potential target genes of miR-sc14,and found that fibroblast growth factor receptor 2 might be a potential target ***,our results show changes of miR-sc14 expression in the sciatic nerve of rats at different time points after nerve ***,up-regulation of miR-sc14 promoted proliferation and migration of Schwann ***,miR-sc14 may be an intervention target to promote repair of peripheral nerve *** study was approved by the jiangsu Provincial Laboratory Animal Management Committee,China on March 4,2015(approval No.20150304-004).

关键词： nerve regeneration novel microRNAs miR-sc14 peripheral nerve injury cell proliferation cell migration Schwann cells fibroblast growth factor receptor 2 biological functions peripheral nerve regeneration regulatory mechanisms neural regeneration

Constant charge method or constant potential method:Which is better for molecular modeling of electrical double layers?

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Journal of Energy Chemistry 2024年第7期94卷 54-60页

作者： Liang Zeng xi Tan xiangyu ji Shiqi Li jinkai Zhang jiaxing Peng Sheng Bi Guang Feng State Key Laboratory of Coal Combustion Schoolof Energy and PowerEngineeringHuazhong Universityof Science and Technology(HUST)Wuhan 430074HubeiChina Sorbonne Universite CNRSPhysico-chimie des Electrolytes et Nanosystemes InterfaciauxPHENIXF-75005 ParisFrance

In molecular modeling of electrical double layers(EDLs),the constant charge method(CCM)is prized for its computational efficiency but cannot maintain electrode equipotentiality like the more resourceintensive constant potential method(CPM),potentially leading to *** certain scenarios,CCM can yield results identical to ***,there are no clear guidelines to determine when CCM is sufficient and when CPM is ***,we conduct a series of molecular simulations across various electrodes and electrolytes to present a comprehensive comparison between CCM and CPM under different charging *** reveal that CCM approximates CPM effectively in capturing equilibrium EDL and current-driven dynamics in open electrode systems featuring ionic liquids or regular concentration aqueous electrolytes,while CPM is indispensable in scenarios involving organic and highly concentrated aqueous electrolytes,nanoconfinement effects,and voltage-driven *** work helps to select appropriate methods for modeling EDL systems,prioritizing accuracy while considering computationalefficiency.

关键词： Electrochemical interface Molecular dynamics Electrode polarization modeling Nanoconfinement effect

Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

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Petroleum Science 2024年第4期21卷 2839-2848页

作者： Yong Hu xi Lu Hai-Bo Wang ji-Chao Fang Yi-Ning Wu jian Fang Sun SINOPEC Petroleum Exploration and Production Research Institute Shandong Key Laboratory of Oilfield Chemistry School of Petroleum Engineering China University of Petroleum (East China)

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in *** the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still *** this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy *** show that molecules in pure wax are arranged in a paralleled *** wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged *** the mass fraction of asphaltenes in asphaltene-wax system(ωasp) is 0-25 wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase of ω*** ωaspincreases from 0 to 25 wt%,and the attraction between asphaltene-wax is stronger than that among *** causes that the wax precipitation point changes from 353 to 333 *** the ωaspincreases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to *** causes that the ordered crystal structure of waxes can't be formed at normal ***,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax ***,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger *** results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

关键词： Heavy oil Interaction mechanism Asphaltenes Waxes Molecular dynamics

Analysis of Water Resources Supply and Demand and Security of Water Resources Development in Irrigation Regions of the Middle Reaches of the Heihe River Basin, Northwest China

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Agricultural Sciences in China 2006年第2期5卷 130-140页

作者： ji xi-bin KANG Er-si CHEN Ren-sheng ZHAO Wen-zhi XlAO Sheng-chun jiN Bo-wen Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 P.R.China Linze Inland River Basin Comprehensive Research Station Chinese Ecosystem Network Research Linze 734200 P.R.China

Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance of water supply and demand in the region was established, and the security of water resource was assessed, from which the results that the effects of unified management of water resources in the Heihe River basin between Gansu Province and Inner Mongolia on regional hydrology are significant with a decrease in water supply diverted from Heihe River and an increase in groundwater extracted. In addition, it was found that the groundwater level has been steadily decreasing due to over pumping and decrease in recharges. In present year （2003）, the volume of potential groundwater in the irrigation districts is far small because of the groundwater overdraft; even in the particular regions, there is no availability of groundwater resources for use. By 2003, water supply is not sufficient to meet the water demand in the different irrigation districts, the sustainable development and utilization of water resources are not secured, and the water supply crisis occurs in Pingchuan irrigation district. Achieving water security for the sustainable development of society, agriculture, economy, industry, and livelihoods while maintaining or improving the abilities of the management and planning of water resources, determining of the reasonable percentage between water supply and groundwater utilization and water saving in agricultural irrigation are taken into account. If this does not occur, it is feared that the present performance of water development and planning may further aggravate the problem of scarcities of water resources and further damage the fragile ecological system.

关键词： middle reaches of Heihe River irrigation region water resources supply and demand balance evaluation of the security of water resources

SERPINH1 promoted the proliferation and metastasis of colorectal cancer by activating PI3K/Akt/mTOR signaling pathway

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1890-1907页

作者： xiao-Sheng jin Lu-xi Chen Ting-Ting ji Rong-Zhou Li Department of Gastroenterology The Third Affiliated Hospital of Wenzhou Medical UniversityRuian 325000Zhejiang ProvinceChina

BACKGROUND Serpin peptidase inhibitor clade H member 1(SERPINH1)was initially recognized as an oncogene implicated in various human ***,the clinical relevance and functional implications of SERPINH1 in colorectal cancer(CRC)remain largely *** To investigate the effects of SERPINH1 on CRC cells and its specific *** Quantitative real-time polymerase chain reaction,western blotting analysis,The Cancer Genome Atlas data mining and immunohistochemistry were employed to examine SERPINH1 expression in CRC cell lines and tissues.A series of in-vitro assays were performed to demonstrate the function of SERPINH1 and its possible mechanisms in *** SERPINH1 demonstrated elevated expression levels in both CRC cells and tissues,manifested at both mRNA and protein *** SERPINH1 levels correlated closely with advanced T stage,lymph node involvement,and distant metastasis,exhibiting a significant association with poorer overall survival among CRC *** investigations unveiled that SERPINH1 overexpression notably bolstered CRC cell proliferation,invasion,and migration in vitro,while conversely,SERPINH1 knockdown elicited the opposite *** set enrichment analysis underscored a correlation between SERPINH1 upregulation and genes associated with cell cycle *** findings underscored the capacity of heightened SERPINH1 levels to expedite G1/S phase cell cycle progression via phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin pathway activation,thereby facilitating CRC cell invasion and *** These findings imply a crucial involvement of SERPINH1 in the advancement and escalation of CRC,potentially positioning it as a novel candidate for prognostic assessment and therapeutic intervention in CRC management.

关键词： Serpin peptidase inhibitor clade H member 1 Colorectal cancer Proliferation Cell cycle Phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin

Isolation and Identification of Different Sources of Salmonella and Comparisons on the Drug Resistance Spectrum Types

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Animal Husbandry and Feed Science 2013年第2期5卷 65-67,72页

作者： CHEN Chao-xi xi Ge-ji TANG Cheng College of Life Science and Technology Southwest University for Nationalities Animal Husbandry and Veterinary Bureau of Heishui County

[ Objective] In order to make out differences between drug resistance spectrum types of different animal sources of Salmonella. [ Meth- otis] Selenite cystine broth, Salmonella- Shigella genus agar medium, CHROMagar Salmonella chromogenic culture, Reveal Salmonella detection kit and molecular biology methods were used for isolation and identification of Salmonella from different animal feces samples. Antibacterialantimi- crobial susceptibility tests of 17 kinds of drugs such as enrofloxacin, apramycin and florfenicol were done on isolated strains with broth microdilution method, and test data was analysed with WHOnet 5.4 software. [ Results ] 699 feces samples from different animals were separated, and 53 strains of Salmonella were achieved with separation rate of 7.58%, among which those of yak, poultry, and pet sources were respectively 4.33%, 9.06% and 8.37%. [ Condusions] Separation rates and drug resistance spectrum types of different animal origin Salmonella varied greatly, among which separation rates and drug resistance spectrum types of yak source Salmonella were the lowest, there was little difference between separation rates of poultry and dog source Salmonella, however there were large differences on drug resistance spectrum types.

关键词： Salmonella Isolation and identification Drug resistance spectrum type