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猪育种中的应激综合征(上)

中国畜牧兽医 1984年第2期 11-14页

作者：陈润生 a.j.webb

猪应激综合征(PSS)是指那些在应激因子的作用下以异常高的频率产生灰白颜色、质地松软和水分渗出的肌肉,并伴随突然死亡的猪所表现的征候群。继各种活体预测应激易感性的方法之后,近年来日益重视对 PSS 的遗传研究。首先是在荷兰(Eikele... 详细信息

猪应激综合征(PSS)是指那些在应激因子的作用下以异常高的频率产生灰白颜色、质地松软和水分渗出的肌肉,并伴随突然死亡的猪所表现的征候群。继各种活体预测应激易感性的方法之后,近年来日益重视对 PSS 的遗传研究。首先是在荷兰(Eikelenboom 和 Min-kema,1974)而后在其他地方的研究都证明幼猪对氟烷麻醉的反应是呈单一隐性基因遗传。这一隐性基因似乎既能提高胴体产量,又同时减少窝仔数和增加 PSS 所造成的损失。因此,有必要控制其基因频率以提高经济效益。本文旨在将 PSS 的遗传方面的近代知识,尤其是有关氟烷敏感性方面加以综述,并探讨将这些知识应用于猪育种计划和未来研究工作中的若

关键词：猪育种母猪屠宰率公猪 PTH 产肉性能氟烷麻醉眼肌面积 HP 周龄大白猪窝仔数皮特兰背膘厚 PSE 应激

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氟烷测验在猪改良中的作用

国外畜牧科技 1981年第5期 28-32页

作者：陈俊英 a.j.webb

近年来,猪应激综合征(PSS)的问题日益引起注意。患应激综合征的猪只很容易发生苍白、松软、液汁渗出的(PSE)猪肉和因应激而突然死亡。最近在几个国家的试验表明,麻醉用的氟烷能捡出单个隐性基因纯合体的猪只,该基因对PSS的易感性及其他... 详细信息

近年来,猪应激综合征(PSS)的问题日益引起注意。患应激综合征的猪只很容易发生苍白、松软、液汁渗出的(PSE)猪肉和因应激而突然死亡。最近在几个国家的试验表明,麻醉用的氟烷能捡出单个隐性基因纯合体的猪只,该基因对PSS的易感性及其他重要经济性状都有重大影响。因此在易感猪群中,现在有可能通过氟烷筛选迅速降低PSS的发生率。氟烷测验在农场条件下很容易进行氟烷测验。让8至12周龄的猪通过面罩吸入混在氧气中的氟烷3～5分钟。作者等人(1978)在爱丁堡动物育种研究组织所作的标准的3分钟测验中,调节氟烷和氧气的吸入量,刚好使猪只在第一分钟内进入麻醉状态,麻醉维持2分钟。在3分钟内后腿发生明显强直的猪只定为氟烷阳性(HP)或“应激敏感”。而在试验期间始终放松的猪只定为氟烷阴性(HN)或“抗应激”。

关键词：氟烷基因公猪母猪皮特兰猪长白猪兰德瑞斯猪

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猪繁育计划的结构和组织

国外畜牧学(猪与禽) 1987年第3期 25-27页

作者：陈润生 a.j.webb Cotswold猪发展公司英国

猪的选择计划需要在养猪设施和技术专长方面投入大量资金。因此,重要的任务是将所取得的遗传改良尽快地传递到最大多数屠宰肉猪。本文讨论适用于广大地区的猪遗传改良计划的结构。遗传改良设计遗传改良方案包括三个不同的步骤:(1)选择... 详细信息

猪的选择计划需要在养猪设施和技术专长方面投入大量资金。因此,重要的任务是将所取得的遗传改良尽快地传递到最大多数屠宰肉猪。本文讨论适用于广大地区的猪遗传改良计划的结构。遗传改良设计遗传改良方案包括三个不同的步骤:(1)选择最优的基础品种,(2)确定基础品种间的最佳

关键词：核心群纯种繁殖群基础群拓扑群

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猪育种中的应激综合征(下)

中国畜牧兽医 1984年第3期 29-33页

作者：陈润生 a.j.webb A.E.Carden

氟烷位点的利用鉴于氟烷位点对生产性能的巨大作用以及HP 反应频率的可改变性,究竟怎样利用氟烷位点来提高经济效益呢?控制该基因频率的成本效益取决于以下几种因素。(1)对性能的经济效应通过改变基因频率获得的利益主要取决于对性能的... 详细信息

氟烷位点的利用鉴于氟烷位点对生产性能的巨大作用以及HP 反应频率的可改变性,究竟怎样利用氟烷位点来提高经济效益呢?控制该基因频率的成本效益取决于以下几种因素。(1)对性能的经济效应通过改变基因频率获得的利益主要取决于对性能的利、害效应间的经济平衡。虽然这些效应在一些品种,(如荷兰兰德瑞斯)已经比较充分地加以证明(Eikelenboom 等,1980),但对其他品种则完全无知。从已报道的表现型和基因型的差异范围(表1和表2)来看,不

关键词：氟烷基因频率血型肌酸激酶位点连锁群杂合体 HP 公猪人工授精丙酮酸激酶受精兰德瑞斯猪长白猪大白猪应激

Error field penetration in j-TEXT tokamak based on two-fluid drift-MHD model

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j-TEXT team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly jumps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

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Fast and Balanced Charge Transport Enabled by Solution-Processed Metal Oxide Layers for Efficient and Stable Inverted Perovskite Solar Cells

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Energy & Environmental Materials 2024年第2期7卷 240-248页

作者： jing Zhang james Mcgettrick Kangyu ji jinxin Bi Thomas webb Xueping Liu Dongtao Liu Aobo Ren Yuren Xiang Bowei Li Vlad Stolojan Trystan Watson Samuel D.Stranks Wei Zhang Advanced Technology Institute(ATI) University of SurreyGuildfordSurrey GU27XHUK SPECIFIC College of EngineeringSwansea UniversityBay Campus SA18ENSwansea UK Cavendish Laboratory University of CambridgeJ JThomson AvenueCambridge CB30HEUK Department of Chemical Engineering&Biotechnology University of CambridgePhilippa Fawcett DriveCambridge CB30ASUK

Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocols,high-temperature heating process,incompatible solvents,etc.),it is still challenging to achieve efficient and reliable all-metal-oxide-based ***,we developed efficient inverted PSCs(IPSCs)based on solution-processed nickel oxide(NiO_(x))and tin oxide(SnO_(2))nanoparticles,working as hole and electron transport materials respectively,enabling a fast and balanced charge transfer for photogenerated charge *** further understanding and optimizing the perovskite/metal oxide interfaces,we have realized an outstanding power conversion efficiency(PCE)of 23.5%(the bandgap of the perovskite is 1.62 eV),which is the highest efficiency among IPSCs based on all-metal-oxide charge transport *** to these stable metal oxides and improved interface properties,ambient stability(retaining 95%of initial PCE after 1 month),thermal stability(retaining 80%of initial PCE after 2 weeks)and light stability(retaining 90%of initial PCE after 1000 hours aging)of resultant devices are enhanced *** addition,owing to the low-temperature fabrication procedures of the entire device,we have obtained a PCE of over 21%for flexible IPSCs with enhanced operational stability.

关键词： fast and balanced charge transfer inverted perovskite solar cells long-term stability low-temperature processing metal oxides

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Storing Freshwater Versus Storing Electricity in Power Systems with High Freshwater Electric Demand

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journal of Modern Power Systems and Clean Energy 2024年第2期12卷 323-333页

作者： Mubarak j.Al-Mubarak Antonio j.Conejo Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOHUSA Department of Electrical Engineering Kuwait UniversityP.O.Box 5969Safat 13060Kuwait Department of Integrated Systems Engineering and the Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOH 43210USA IEEE

We consider a power system whose electric demand pertaining to freshwater production is high(high freshwater electric demand),as in the Middle East,and investigate the tradeoff of storing freshwater in tanks versus storing electricity in batteries at the day-ahead operation *** storing freshwater and storing electricity increase the actual electric demand at valley hours and decrease it at peak hours,which is generally beneficial in term of cost and ***,to what extent?We analyze this question considering three power systems with different generation-mix configurations,i.e.,a thermal-dominated mix,a renewable-dominated one,and a fully renewable *** generation-mix configurations are inspired by how power systems may evolve in different countries in the Middle *** production uncertainty is compactly modeled using chance *** draw conclusions on how both storage facilities(freshwater and electricity)complement each other to render an optimal operation of the power system.

关键词： Power system operation freshwater production and transportation coordination day-ahead scheduling

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Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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