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合成生物学策略发现新型核糖体肽Xenopeptide

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科学通报 2024年第10期69卷 1361-1372页

作者：莫天录曾丹丹马溯泽贾一飞韩沅均丁伟张琪上海理工大学健康科学与工程学院上海200093 复旦大学化学系上海200433 上海交通大学生命科学技术学院微生物代谢国家重点实验室上海200240

S-腺苷甲硫氨酸自由基(rSAM)酶家族是目前已知的最大酶超家族之一,由22000多个成员组成.这些酶在大自然中广泛存在,被认为是地球上最早的生物催化剂之一.随着大量的微生物基因组信息被解析,分析显示,微生物中大量核糖体肽类天然产物的... 详细信息

S-腺苷甲硫氨酸自由基(rSAM)酶家族是目前已知的最大酶超家族之一,由22000多个成员组成.这些酶在大自然中广泛存在,被认为是地球上最早的生物催化剂之一.随着大量的微生物基因组信息被解析,分析显示,微生物中大量核糖体肽类天然产物的生物合成基因簇中含有rSAM酶;其中Xenorhabdus、Yersinia和Erwinia三个属的基因组中均含有一个高度保守的rSAM酶负责其相邻核糖体肽的前体修饰,此类前体肽和rSAM酶构成的XYE系统所合成的化合物鲜有报道.本研究合成一个来源于Xenorhabdus ***12.1的XYE系统的前体肽和rSAM修饰酶基因,在大肠杆菌中进行共表达,得到新型核糖体肽Xenopeptide,通过结构解析发现,rSAM酶XenB负责分子内2个碳碳键的形成.本研究为微生物中此类化合物的深度挖掘和合成生物学改造提供了理论支撑.

关键词： S-腺苷甲硫氨酸自由基酶核糖体肽翻译后修饰合成生物学

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基于小样本学习的精分患者脑电信号分析方法

太原师范学院学报（自然科学版） 2024年第2期23卷 35-41页

作者：贾亦非尹梦真王懋云王佳明太原学院计算机科学与技术系山西太原030032 太原师范学院计算机科学与技术学院山西晋中030619

目前很多机器学习方法都建立在大量数据的需求上,但在实际的生产生活中,有时很难获得大批量的数据.本文提出将小样本学习技术应用于脑电信号分析上,以增强分类精度,提高分析性能.实验通过对采集到的脑电信号进行预处理,再将其通过预训... 详细信息

目前很多机器学习方法都建立在大量数据的需求上,但在实际的生产生活中,有时很难获得大批量的数据.本文提出将小样本学习技术应用于脑电信号分析上,以增强分类精度,提高分析性能.实验通过对采集到的脑电信号进行预处理,再将其通过预训练模型的卷积层和池化层输出的高维特征向量作为输入数据进行特征提取,最后用小样本学习训练模型,实现在数据集规模较小的情况下达到较好的分类或预测效果.该方法结合了卷积神经网络和元学习的思想,通过在少量标记数据上进行训练,实现了对未标记数据的快速适应.实验结果表明,该方法在小样本情况下具有更好的分类精度和泛化能力,相较于传统的机器学习方法,具有更高的应用价值,可以为精神分裂症疾病的诊断提供参考.

关键词：小样本学习脑电信号卷积神经网络分类精度精神分裂症

Habitat selection and food choice of White-naped Cranes(Grus vipio)at stopover sites based on satellite tracking and stable isotope analysis

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Avian Research 2022年第4期13卷 468-476页

作者： Yunzhu Liu Lan Wu jia Guo Shengwu jiao Sicheng Ren Cai Lu Yuyu Wang yifei jia Guangchun Lei Li Wen Liying Su Centre for East Asian-Australasian Flyway Studies Beijing Forestry UniversityBeijing100083China School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing100083China Research Institute of Subtropical Forestry Chinese Academy of ForestryWetland Ecosystem Research Station of Hangzhou BayHangzhou311400China Science Economics and Insights DivisionNSW Department of PlanningIndustry and EnvironmentSydney2150Australia Department of Earth and Environmental Sciences Macquarie UniversitySydney2109Australia International Crane Foundation BarabooWI53913USA

By combining satellite tracking,land-cover extracted from Landsite 8 images,and the traditional stable isotope analysis,we studied the habitat selection and food preference of a vulnerable migratory waterbird,the Whitenaped Crane(Grus vipio),in one of its key stagging sites,the Shandian River Basin in the semi-arid northern China,to provide knowledge that is critical for its conservation in the *** results showed that the White-naped Cranes used both uplands and natural wetlands in the stopover *** the cranes used farmland and natural land cover equally as night-time roosting grounds,they spent most daytime foraging at *** the extensive usage of croplands as their foraging ground,the Bayesian mixing models based on stable isotopic analysis revealed that crop residues after harvesting,such as Maize(Zea mays)and Naked Oat(Avena chinensis),were only a small fraction of the White-naped Cranes’diet(~19%),and their diet composited mainly natural plants,such as Allium ledebourianum,Potentilla anserina,and ***,more than 20%of the total wetlands in the region were modelled as home range of the *** contrast,less than 10%of croplands and about 1%of the unused uplands were identified as home *** addition,the entire core habitats were located in natural *** findings demonstrated the importance of natural wetlands for the survival of the threatened ***,the satellite-derived land cover data showed that croplands increased rapidly in the last decade in this area,at the expense of natural *** the sharp decrease of White-naped Crane population in China,the conservation of stopover sites becomes *** on our analysis,we recommend the following management actions:conserving adequate natural wetland area,regulating anthropogenic pressures such as the use of herbicides,expanding the duration and extent of current conservation regulations,establishing a comprehensive monitoring progr

关键词： Biased random bridge Food resource Stopover Utilization distribution White-naped Crane

Global population estimate and conservation gap analysis for the Nordmann's Greenshank(Tringa guttifer)

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Avian Research 2023年第2期14卷 250-256页

作者： Ranxing Cao Waner Liang jia Guo Hongyan Yang Lili Sun Qing Chen Tao Yu Sicheng Ren Cai Lu Guangchun Lei yifei jia School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing100083China Center for East Asian-Australasian Flyway Studies Beijing Forestry UniversityBeijing100083China Shenzhen Mangrove Wetlands Conservation Foundation Shenzhen518040China Qingdao Birding Association Qingdao266100China

Nordmann's Greenshank(Tringa guttifer)is a globally endangered species that has received little research *** is threatened by rapid habitat loss,an incomplete network of protected sites,and lack of long-term data on population *** science data can be combined with survey data to support population estimation and conservation gap *** 2020 to 2021,Nordmann's Greenshank was surveyed in Tiaozini,Xiaoyangkou,and Dongling on the southern coast of jiangsu Province,China,and the global population of the species was re-evaluated using the data *** integrated citizen science data from eBird and the China Bird Report from 2000 to 2020 with the survey results to identify important habitats harboring over 1%of its total population,and compared this data with existing protected areas to identify gaps in its global *** survey found that Tiaozini supported at least 1194 ***,its global population was reestimated to be ***,45 important habitats were identified based on citizen data and survey *** 44.4%and 50.0%of the priority sites in the world and China,respectively,are located outside protected areas,the Conservation Effectiveness Index(C)is 68.4%and 71.1%,respectively,showing that the current coverage of protected areas for this part of its range is *** study presents the most complete and recent population data to *** is the most important migration stopover site for Nordmann's *** species is under threat in terms of breeding,wintering,and stopover ***,we suggest improving monitoring,establishing new protected sites to complete the habitat protection network,and improving the effectiveness of existing habitat protection strategies,including further developing high tide roosting sites.

关键词： Citizen science Conservation gaps Nordmann's Greenshank Population estimate

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车用燃料电池散热性能实验研究

储能科学与技术 2024年第2期13卷 390-395页

作者：白静范惠芳崔四齐许闯张毅关斯泽杨涵斐贾一飞耿树伟郑慧凡中原工学院能源与环境学院河南郑州451191

质子交换膜燃料电池(PEMFC)作为能效转换率高、清洁可靠的发电装置,在交通、储能、航天及军事等领域有着广泛应用。为了解决质子交换膜燃料电池散热密度高、发热量大、散热效率低等突出问题,本文针对散热量为15 kW的质子交换膜燃料电池... 详细信息

质子交换膜燃料电池(PEMFC)作为能效转换率高、清洁可靠的发电装置,在交通、储能、航天及军事等领域有着广泛应用。为了解决质子交换膜燃料电池散热密度高、发热量大、散热效率低等突出问题,本文针对散热量为15 kW的质子交换膜燃料电池,设计并搭建了一套具有四种不同流程换热器的车用燃料电池散热系统实验台。分别使用两相冷却工质HFE-7100和乙二醇水溶液作为冷却工质,探究了在35℃的高温环境中,两种工质在不同流程换热器和不同工质流量下的散热性能和系统能效比(Energy Efficiency Rating, EER)。结果表明,在相同的流程下,采用HFE-7100两相散热方式相对于采用乙二醇水溶液液冷散热方式散热量提升率在81.2%~98.8%之间,系统EER提升率在68.2%~88.6%之间。且在4种不同流程下,3流程的系统散热效果和节能效果最佳,两相工质HFE-7100散热量和系统EER分别达到14.4 kW和20.5 kW/kW,液冷工质乙二醇水溶液散热量和系统EER分别达到7.7 kW和12.1 kW/kW。冷却工质流量为4 L/min时,系统节能效果较好,其两相和液冷散热系统EER分别能达到20.9 kW/kW和10.5 kW/kW。

关键词：质子交换膜燃料电池不同流程换热器两相冷却工质 EER

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大数据背景下本科院校学生群体画像构建与应用分析

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数字通信世界 2024年第3期 108-110页

作者：潘琛董国珍李奇泽付国霞贾亦非太原学院山西太原030032

近年来,大数据技术越来越成熟,本科院校普遍利用它来辅助教学,因此,以大数据技术为支撑的学生群体画像出现在了大众的视野中。一些学校通过构建数字模型、设计数字系统和建立预警机制建构了比较健全的学生群体画像,收集、存储、整合、... 详细信息

近年来,大数据技术越来越成熟,本科院校普遍利用它来辅助教学,因此,以大数据技术为支撑的学生群体画像出现在了大众的视野中。一些学校通过构建数字模型、设计数字系统和建立预警机制建构了比较健全的学生群体画像,收集、存储、整合、分析学生的相关数据,形成了标签化的学生画像,并将其应用到了思想政治教育、就业指导等人才培养方面,不仅简化了学校及教师的学生教育、管理工作,还提高了学生的自律自勉能力。

关键词：大数据本科院校学生群体画像

基于肠-脑-皮轴理论探讨从肝肺论治成年女性青春期后痤疮

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内蒙古中医药 2024年第7期43卷 81-84页

作者：曾言敏贾一飞郎朗谢晶杰史邢田成都中医药大学四川成都610032

青春期后痤疮以成年女性为主要发病人群,本病作为一种慢性炎症性皮肤病具有一定的损容性且容易反复,易对患者身心造成较大的不良影响。近年来研究发现肠-脑-皮轴理论在痤疮的发病机制中有较大作用。而本病中医病机与气机失调、津液输布... 详细信息

青春期后痤疮以成年女性为主要发病人群,本病作为一种慢性炎症性皮肤病具有一定的损容性且容易反复,易对患者身心造成较大的不良影响。近年来研究发现肠-脑-皮轴理论在痤疮的发病机制中有较大作用。而本病中医病机与气机失调、津液输布障碍关系密切,这与肝肺之功能关系密切,肝、肺、大肠、皮肤之间的协同作用与肠-脑-皮轴理论有一定的相关性。故本文通过分析肠-脑-皮轴理论解释从肝肺论治成年女性青春期后痤疮的可行性,为中医临床辨治成年女性青春期后痤疮提供理论支持。

关键词：肠-脑-皮轴肠道菌群精神心理青春期后痤疮

Online Consensus Control of Nonlinear Affine Systems From Disturbed Data

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 551-553页

作者： yifei Li Wenjie Liu jian Sun Chen Chen jia Zhang Gang Wang National Key Laborary of Autonomous Intelligent Unmanned Systems Beijing Institute of TechnologyBeijing 100081 Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Dear Editor,In this letter, we introduce a novel online distributed data-driven robust control approach for learning controllers of unknown nonlinear multi-agent systems(MASs) using state-dependent representations.

关键词： agent online Online

Water regulation： a Sword of Damocles for migratory waterbirds in China？

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Science China(Life Sciences) 2017年第5期60卷 548-550页

作者： yifei jia Guangchun Lei Xiubo Yu Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China School of Nature Conservation Beijing Forestry University Beijing 100083 China University of Chinese Academy of Sciences Beijing 100049 China

Dams and reservoirs,regulating water levels for irrigation,hydropower and flood control,are sometimes considered as artificial managed *** research has shown that increased water surface of reservoirs have become habitats for some species of migratory ***,hydraulic engineering can be a Sword of Damocles for *** water levels may dramatically alter a wetland

关键词：栖息地水调节中国候鸟水库调节人工管理水利工程大坝