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美国目前和未来的保育猪饲养方案

饲料工业 2013年第12期34卷 60-64页

作者： Bob Goodband Jon Bergstrom mike tokach Joel deRouchey Steve dritz Jim Nelssen 美国堪萨斯州立大学

在过去的20年内美国的猪产业发生了翻天覆地的变化。多址生产系统对畜群的健康和控制断奶仔猪链产生了极大的作用。然而一个成功的断奶仔猪营养方案其基本原则对于任何日龄断奶的仔猪来讲都是相似的。可以归纳成三点：①在断奶时，仔猪... 详细信息

在过去的20年内美国的猪产业发生了翻天覆地的变化。多址生产系统对畜群的健康和控制断奶仔猪链产生了极大的作用。然而一个成功的断奶仔猪营养方案其基本原则对于任何日龄断奶的仔猪来讲都是相似的。可以归纳成三点：①在断奶时，仔猪尽可能的体重大；②尽可能快的将日粮从复合日粮转化为简单日粮；③重点关注保育仔猪管理。此外，在关国过去的10年通过遗传选育的手段，使窝产仔数大约增加了1．5头，仔猪断奶的日龄也相应地增加到平均为19-23d。当每头母猪产仔数增加以后，由于初生活仔数的增加，有更多体重轻的仔猪出生，这将是生产者所面临的挑战。因此，对生产者来说，了解影响初生体重轻的仔猪一生的生产性能以及收益的因素是非常必要的。

关键词：保育猪饲养方案断奶日龄窝产仔数

Large-scale destress blasting for seismicity control in hard rock mines:A case study

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International Journal of Mining Science and Technology 2020年第2期30卷 141-149页

作者： Isaac Vennes Hani Mitri damodara Reddy Chinnasane mike Yao department of Mining and Materials Engineering McGill UniversityMontrealQuebec H3A 0E8Canada Copper Cliff Mine Vale Canada LtdSudbury P0M 1N0Canada

destress blasting is a rockburst control technique where highly stressed rock is blasted to reduce the local stress and stiffness of the rock,thereby reducing its burst *** technique is commonly practiced in deep hard rock mines in burst prone developments,as well as in sill or crown pillars which become burst-prone as the orebody is ***-scale destressing is a variant of destress blasting where panels are created parallel to the orebody strike with a longhole,fanning blast pattern from cross cut drifts situated in the host *** aim of panel destressing is to reduce the stress concentration in the ore blocks or pillars to be *** paper focuses on the large-scale destress blasting program conducted at Vale's Copper Cliff Mine(CCM)in Ontario,*** merits of panel destressing are examined through field measurements of mining induced stress changes in the *** destressing mechanism is simulated with a rock fragmentation factor(a)and stress reduction/dissipation factor(b).A 3d model is built and validated with measured induced stress *** is shown that the best correlation between the numerical model and field measurements is obtained when the combination of a and b indicates that the blast causes high fragmentation(a=0.05)and high stress release(b=0.95)in the destress *** is demonstrated that the burst proneness of the ore blocks in the panel stress shadow is reduced in terms of the brittle shear ratio(BSR)and the burst potential index(BPI).

关键词： destress blasting Preconditioning Rockbursts Strainbursts Numerical modeling

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新疆高粱种质资源萌发期抗旱性综合评价

草地学报 2024年第2期32卷 553-561页

作者：岳丽山其米克王卉再吐尼古丽·库尔班毛红艳刘敏新疆农业科学院粮食作物研究所新疆乌鲁木齐830091 新疆农业科学院农业质量标准与检测技术研究所新疆乌鲁木齐830091

为研究新疆本土高粱(Sorghum)种质资源的抗旱性并筛选萌发期有效抗旱指标,以来源于不同地区的207份高粱种质资源为研究对象,采用PEG-6000溶液模拟干旱胁迫条件,对高粱萌发相关的10个指标进行分析,在主成分分析基础上采用隶属函数法对各... 详细信息

为研究新疆本土高粱(Sorghum)种质资源的抗旱性并筛选萌发期有效抗旱指标,以来源于不同地区的207份高粱种质资源为研究对象,采用PEG-6000溶液模拟干旱胁迫条件,对高粱萌发相关的10个指标进行分析,在主成分分析基础上采用隶属函数法对各高粱品种的抗旱性进行综合评价。结果表明:在干旱胁迫下,高粱的各萌发指标均受到影响。其中,相对发芽势与萌发抗旱指数相关性最强,前3个主成分累计贡献率为78.328%,分别反映高粱在干旱胁迫下的生长、萌发及发育情况。根据综合得分将207份种质划分为5类,即高度抗旱种质12份、抗旱种质28份、中等抗旱种质87份、干旱敏感种质64份和高度敏感种质16份。筛选出高粱萌发期抗旱性鉴定的重要指标为相对芽鲜重、萌发抗旱指数、相对干物质转运率,建立了可准确评估高粱萌发期抗旱性的回归方程,为高粱萌发期抗旱性种质筛选提供理论依据。

关键词：高粱种质干旱胁迫主成分分析萌发期综合评价

Regeneration status of riparian tree species in two sites that differ in land-use in the Okavango delta,Botswana

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Journal of Forestry Research 2017年第5期28卷 1073-1082页

作者： Gaolathe Tsheboeng mike Murray-Hudson Keotshephile Kashe Okavango Research Institute

Human communities from the Okavango delta benefit from the services and goods provided by the wetland ecosystem through its riparian vegetation. These include food and timber products used for the construction of shelter and canoes. despite the importance of riparian tree species in the delta, their regeneration structure is currently unknown. For riparian trees to be managed sustainably, information on the current regeneration status of the trees under different land uses is needed. The Moremi game reserve (protected area) and Seronga (communal area) were selected for this study on the regeneration of riparian tree species of Croton megalobotrys Müll. Arg, Philenoptera violacea (Klotzsch) Schrire, Senegalia nigrescens (Acacia nigrescens) Oliv and diospyros mespiliformis Hochst. ex A. dc. The height of each individual tree was estimated in randomly selected 30 plots (15 from each site) of 20 × 50 m for assignment to five regeneration classes: 0-0.5, 0.5-1, 1-2, 2-4 and >4 m. Linear regression was used to infer regeneration status of each species. An independent-sample Student’s t test was used to determine any significance differences in seedling density/ha and sapling density/ha between different sites at p diospyros mespiliformis populations had an unstable regeneration structure in both sites, while P. violacea regeneration was stable regardless of land-use type. Croton megalobotrys and S. nigrescens had an unstable regeneration pattern in Seronga, while in Moremi it was stable; thus, the regeneration structure of C. megalobotrys and S. nigrescens is affected by land-use. This result implies that intervention is needed to conserve the two species in Seronga where the current land-use appears to be incompatible with regeneration; d. mespiliformis also needs to be conserved in both Moremi and Seronga.

关键词： Conservation Regeneration Riparian Okavango and wetlands

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想象难以设想的事物:艺术镜头下的深时

装饰 2024年第8期 49-61页

作者： [美]J.d.塔拉塞克汪芸(译) 美国国家科学院《装饰》

J.d.塔拉塞克是一位策展人、研究者和作家,他热衷于通过协作与综合性的工作探索艺术与科学的交叉点。他是美国国家科学院文化项目的负责人,该项目专注于探索科学、医学、技术和文化之间的相互关系;同时,他是《莱奥纳多》(麻省理工学院出... 详细信息

J.d.塔拉塞克是一位策展人、研究者和作家,他热衷于通过协作与综合性的工作探索艺术与科学的交叉点。他是美国国家科学院文化项目的负责人,该项目专注于探索科学、医学、技术和文化之间的相互关系;同时,他是《莱奥纳多》(麻省理工学院出版)的主编。塔拉塞克是dASER (华盛顿特区艺术科学晚会)的创始人和主持人,dASER是每个月在美国国家科学院举办的沙龙,他主持该系列活动已逾13载。此外,塔拉塞克还担任亚利桑那州立大学和美国国家科学院联合出版的《科学技术杂志》(Science and Technology Magazine)的艺术顾问。塔拉塞克在美国国家科学院策划了多个展览,其中包括“想象深时”(Imagining deep Time,2014年)、“梦幻解剖学”(Visionary Anatomies,在2004年至2006年期间在史密森学会巡展)、“吸收+传输:迈克与道格·斯塔恩的作品”(Absorption+Transmission:Work by mike and doug Starn)。本文即塔拉塞克为“想象深时”展览撰写的文章,展览中的艺术家以代表了个人艺术探索的多样化的形式探索了“深时”理念。

关键词：美国国家科学院史密森学会联合出版麻省理工学院华盛顿特区塔拉艺术与科学艺术顾问

Improvements in Inversion of Magnetic Resonance Exploration-Water Content, decay Time, and Resistivity

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Journal of China University of Geosciences 2009年第3期20卷 592-605页

作者： Ugur Yaramanci mike Müller-Petke Leibniz Institute of Applied Geophysics Stilleweg 2 Hannover D-30655 Germany Berlin University of Technology Ackerstrasse 71-76 Berlin D-13355 Germany

In this review article, we present recent developments and improvements in magnetic resonance sounding （MRS）, a newly established geophysical exploration method that provides unique information about hydrogeophysical properties due to its direct sensitivity to hydrogen protons and proton dynamics. Starting with the most sophisticated and complete MRS formulation, we give a detailed view on how to solve the equation, i.e., inverting exactly for all model parameters： water content, decay time, and resistivity. Giving a short review of general inversion schemes used in geophysics, the special properties of MRS inversion are evaluated and the development of MRS inversion over recent years is shown. We present the extension of MRS to magnetic resonance tomography （MRT）, i.e., the extension to two-dimensional investigations and appropriate inversions. Finally, we address restrictions, limitations, and inconsistencies as well as future developments.

关键词： magnetic resonance sounding (MRS) magnetic resonance tomography (MRT) inversion modeling water content decay time resistivity.

Ron receptor-dependent gene regulation in a mouse model of endotoxin-induced acute liver failure

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Hepatobiliary & Pancreatic diseases International 2012年第4期11卷 383-392页

作者： Rishikesh M Kulkarni Louis W Kutcher William d Stuart daniel J Carson mike A Leonis Susan E Waltz departments of Cancer and Cell Biology University of CincinnatiCincinnatiOH 45267-0521USA Biology University of CincinnatiCincinnatiOH 45267-0521USA division of Gastroenterology Hepatology and NutritionCincinnati Children's Hospital Medical CenterCincinnatiOH 45229USA department of Research Shriner's Hospital for Children and Cincinnati Veterans Affairs Medical CenterCincinnatiOH 45267-0521USA

BACKGROUNd:Prior experimentation has shown that loss of the tyrosine kinase(TK) signaling domain of the Ron receptor leads to marked hepatocyte protection in a model of lipopolysaccharideinduced acute liver failure(ALF) in d-galactosamine(GalN)sensitized *** aim of this study was to identify the role of Ron in the regulation of hepatic gene ***:Microarray analyses were performed on liver RNA isolated sequentially from wild-type(WT) and TK-/mice during the progression of *** array data were validated using Western and immunohistochemistry analyses as well as with ex vivo culture ***:At baseline,101 genes were differentially expressed between WT and TK-/-livers,which regulate processes involved in hypoxia,proliferation,apoptosis and *** hour after ALF induction,WT livers exhibited increased cytokine expression compared to TK-/-livers,and after 4 hours,an induction of suppressor of cytokine signaling(SOCS) genes as well as JAK-STAT pathway activation were prominent in TK-/livers compared to ***:Our studies suggest a novel hepato-protective mechanism in Ron TK-/-mice wherein increased and sustained SOCS production and JAK-STAT activation in the hepatocyte may inhibit the destructive proinflammatory milieu and promote survival factors which blunt hepatic death and the ensuing development of ALF.

关键词： Mst1R suppressors of cytokine signaling Met receptor hepatocyte growth factor-like protein

Mitigation of Blast Effects on Aluminum Foam Protected Masonry Walls

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Transactions of Tianjin University 2008年第B10期14卷 558-562页

作者： GRIFFITH mike School of Civil Environmental and Mining Engineering The University of Adelaide SA 5005 Australia

Terrorist attacks using improvised explosive devices （IEd） can result in unreinforced masonry （URM） wall collapse. Protecting URM wall from IEd attack is very complicated. An effective solution to mitigate blast effects on URM wall is to retrofit URM wails with metallic foam sheets to absorb blast energy. However, mitigation of blast effects on metallic foam protected URM walls is currently in their infancy in the world. In this paper, numerical models are used to simulate the per- formance of aluminum foam protected URM walls subjected to blast loads. A distinctive model, in which mortar and brick units of masonry are discritized individually, is used to model the perform- ance of masonry and the contact between the masonry and steel face-sheet of aluminum foam is modelled using the interface element model. The aluminum foam is modelled by a nonlinear elas- toplastic material model. The material models for masonry, aluminum foam and interface are then coded into a finite element program LS-dYNA3d to perform the numerical calculations of response and damage of aluminum foam protected URM walls under airblast loads. discussion is made on the effectiveness of the aluminum foam protected system for URM wall against blast loads.

关键词： mitigation blast loads aluminium foam masonry

A comparison of animal color measurements using a commercially available digital color sensor and photograph analysis

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Current Zoology 2020年第6期66卷 601-606页

作者： Alex d.Potash daniel U.Greene Gabrielle A.Foursa Verity L.Mathis L.mike Conner Robert A.McCleery department of Wildlife Ecology and Conservation University of Florida Institute of Food and Agricultural ScienceGainesvilleFL 32611USA Weyerhaeuser Company Environmental Research SouthColumbusMS 39701USA department of Biology University of FloridaGainesvilleFL 32611USA Florida Museum of Natural History University of FloridaGainesvilleFL 32611USA The Jones Center at Ichauway NewtonGA 39870USA

An animal's pelage,feather,or skin color can serve a variety of functions,so it is important to have multiple standardized methods for measuring *** of the most common and reliable methods for measuring animal coloration is the use of standardized digital photographs of *** tech no logy in the form of a commercially available handheld digital color sensor could provide an alter native to photography-based animal color *** determine whether a digital color sensor could be used to measure animal coloration,we tested the ability of a digital color sensor to measure coloration of mammalian,avian,and lepidopteran museums *** compared results from the sensor to measurements taken using traditional photography *** study yielded significant differences between photography-based and digital color sensor measurements of brightness(light to dark)and colors along the green to red *** was no difference between photographs and the digital color sensor measurements for colors along the blue to yellow *** average difference in recorded color(AE)by the 2 methods was above the threshold at which humans can perceive a *** were sign讦icant correlations between the sensor and photographs for all measurements indicating that the sensor is an effective animal coloration measuring ***,the sensor's small aperture and narrow light spectrum range designed for human-vision limit its value for ecological *** discuss the conditions in which a digital color sensor can be an effective tool for measuring animal coloration in both laboratory settings and in the field.

关键词： animal coloration color measurement comparative method digital photography museum specimens Nix color sensor