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渔业合作社产权:它们如何运作(及运作效果)

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世界银行经济评论 2017年第2期31卷 1-50页

作者：奥克塔瓦·阿布尔托-奥洛佩齐亚希瑟·M.莱斯利奥斯汀·麦克-克莱恩西里尼其斯·纳迦瓦拉普西拉·M.W.雷迪雷拉·思凡内加利福尼亚圣迭戈大学斯克里普斯海洋研究所缅因大学达令海洋中心布鲁金斯学院社会动力学和政策中心 Acumen有限公司美国自然保育协会可持续发展加利福尼亚海洋科学信托基金会

将产权转移给当地机构已经逐步成为发展中国家自然资源管理中的一种强制性策略。加利福尼亚墨西哥湾渔业合作社运营中对产权的使用,为理论和实证分析提供了一种良好的背景。动态理论模型论证了产权的存在、资源的流动性和可预见的环境... 详细信息

将产权转移给当地机构已经逐步成为发展中国家自然资源管理中的一种强制性策略。加利福尼亚墨西哥湾渔业合作社运营中对产权的使用,为理论和实证分析提供了一种良好的背景。动态理论模型论证了产权的存在、资源的流动性和可预见的环境波动是如何影响渔业合作社管理选择的。有一种较积极的管理形式:合作社领导对合作社成员的捕捞物支付更低的价格,因为低价会降低捕捞努力量。通过加利福尼亚湾三个合作社关于价格和渔获量的三年航海日志数据,我们对该模型的启示进行了实证检验。其中一个合作社享有产权,而另外两个合作社则未享有产权。

关键词：产权转移合作社运作效果渔业自然资源管理加利福尼亚发展中国家墨西哥湾

Integrated Design of a Compact and Lightweight S-Band Traveling-Wave Tube Amplifier for a New Class of Microwave Power Module

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Journal of Electromagnetic Analysis and Applications 2013年第3期5卷 96-102页

作者： heather Song leslie Tekamp Frank Francisco Ming-Chieh Lin Peter H. Stoltz David Smith Gil Wong Choi Jin Joo Choi Department of Electrical and Computer Engineering University of Colorado Colorado Springs USA Department of Electrical and Computer Engineering University of Colorado Colorado Springs USA Department of Electronics Convergence Engineering Kwangwoon University Seoul South Korea. Samsung Thales Co. Yongin-Si South Korea Tech-X Co. Boulder USA Triton Services Inc. Breinigsville USA

A new class of compact and lightweight S-band 1 kW traveling-wave tube (TWT) is being developed for a microwave power module (MPM) that will be used for phased antenna array radar applications. The proposed S-band MPM provides a tenfold peak power increase compared to state-of-the-art S-band MPMs. In this paper, the design of the vacuum power booster TWT part of the MPM is presented. The compact and lightweight S-band TWT is driven by a 6 kV, 0.9 A electron beam. The amplifier is predicted by large-signal simulations to generate over 1 kW at S-band with 25 dB saturated gain and over 40% efficiency. The stability from unwanted oscillations has been investigated. To suppress the oscillations, the helix circuit has been coated with carbon composite material. The coaxial input and output antennas have been fabricated. For efficiency enhancement, a multi-stage depressed collector (MDC) has been designed using a 3D particle-in-cell (PIC) simulator, VORPAL. The collector design makes use of a current loop based on a feedback mechanism for effective design process. The integrated designs of a helix circuit, an electron gun, a periodic permanent magnet (PPM), antennas, and a collector are presented.

关键词： TWT MPM Compact Lightweight Feedback Current Loop Multi-Stage Collector

Social-epigeneticmediators for racial disparities in pulmonary impairment among childhood cancer survivors

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Cancer Communications 2023年第2期43卷 290-293页

作者： Nan Song Qian Dong Cheng Chen Qian Li heather Mulder Emily Plyler John Easton Emily Walker Scott Olson Geoffrey Neale Kevin RKrull Deo Kumar Srivastava Kirsten K.Ness Jinghui Zhang Melissa M.Hudson leslie L.Robison I-Chan Huang Zhaoming Wang Department of Epidemiology and Cancer Control St.Jude Children’s Research HospitalMemphisTN 38105USA College of Pharmacy Chungbuk National UniversityCheongjuChungbuk 28160South Korea School of Public Health Shanghai Jiaotong UniversityShanghai 200025P.R.China Department of Biostatistics St.Jude Children’s Research HospitalMemphisTN 38105USA Department of Computational Biology St.Jude Children’s Research HospitalMemphisTN 38105USA Hartwell Center St.Jude Children’s Research HospitalMemphisTN 38105USA Department of Oncology St.Jude Children’s Research HospitalMemphisTN 38105USA

Dear Editor Previous research found that childhood cancer survivors of African ancestry have significantly higher morbidity and mortality than those of European ancestry[1].However,after adjusting for socio-economic factors,the magnitudes of racial health disparities are either substantially decreased or become statistically non-significant[1],suggesting that social and economic determinants may contribute to racial health ***,we conducted epigenome-wide association studies(EWAS)for three key social determinants of health(SDOHs),namely,personal educational attainment,personal income,and neighborhood deprivation among survivors of childhood cancer,where 130 epigenome-wide significant SDOH-CpG associationswere identified among European ancestry survivors,and 25 of which were also validated in African ancestry survivors[2].Notably,many SDOH-associated CpG sites are also associated with tobacco use.

关键词： vivo cancer mortality

Milk Replacer Acidification for Free-Access Feeding: Effects on the Performance and Health of Veal Calves

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Open Journal of Animal Sciences 2016年第3期6卷 234-246页

作者： Cynthia G. Todd Ken E. leslie Suzanne T. Millman Jan M. Sargeant heather Migdal Kathleen Shore Neil G. Anderson Trevor J. DeVries Department of Population Medicine Ontario Veterinary College University of Guelph Guelph ON Canada Department of Veterinary Diagnostic & Production Animal Medicine Iowa State University Ames IA USA Centre for Public Health and Zoonoses University of Guelph Guelph ON Canada Department of Animal Biosciences University of Guelph Guelph ON Canada Grober Nutrition Cambridge ON Canada Ontario Ministry of Agriculture Food and Rural Affairs Veterinary Science and Policy Unit Elora ON Canada

Objectives of this study were to investigate the effects of milk replacer (MR) acidification for free- access feeding on pre- and post-weaning performance, morbidity and mortality of calves. Calves were randomly assigned to free-access feeding of acidified (ACID, n = 31) or non-acidified (NON, n = 31) MR, and weaned at 42 days. ACIDMR was prepared to pH 4.0 - 4.5 using formic acid. Intakes were measured daily and weights weekly. Samples of ACID and NON MR were analyzed for coliform and aerobic bacterial growth. After weaning, calves transitioned to a grain-fed veal diet, weighed every 2 weeks. At slaughter (approximately 6 months of age), lungs were evaluated for gross pathological changes and dressed carcass weights were obtained. Generalized linear mixed models were constructed to examine the effects of MR acidification. Differences by treatment group for pre- and post-weaning morbidity and mortality were tested using Pearson’s χ2 and Fisher’s exact tests. ACID calves consumed less MR than NON (10.6 vs. 11.7 L/d, P = 0.02). Acidification tended to promote earlier onset of starter ration consumption (32.0 vs. 39.5 d, hazard ratio = 1.5, P = 0.07), but did not affect average daily starter ration or water intakes across the pre-weaning period. ACID and NON calves did not differ for BW at weaning, pre- or post-weaning ADG or dressed carcass weight. ACID MR had less coliform (P < 0.001) and aerobic bacterial growth (P < 0.001) than NON MR, but odds of disease treatment and mortality did not differ. ACID calves tended to have lower odds of pulmonary lesions during post-mortem inspection than NON calves (OR = 0.3, P = 0.07). These results indicate that under free-access feeding conditions, acidification limited bacterial growth and MR intake, but there were no long-term impacts of acidification on calf performance or health. In conclusion, acidification to pH 4.0 - 4.5 will significantly reduce bacterial growth in milk fed to calves.

关键词： Acidified Milk Feeding Free-Access Milk Feeding Health Growth Veal Calves

母乳喂养史和子宫内膜异位症发生的风险：前瞻性队列研究

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英国医学杂志中文版 2018年第3期21卷 177-178页

作者： leslie V Farland A heather Eliassen Rulla M Tamimi Donna Spiegelman Karin B Michels Stacey A Missmer 龚丽云王淑珍不详首都医科大学附属北京朝阳医院妇产科

目的研究经产妇母乳喂养、纯母乳喂养、产后闭经时间与子宫内膜异位症发病率的关系。设计前瞻胜队列研究。

关键词：内膜增生学习历史风险子宫事件母乳