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61.
Based on a qualitative methodology that includes in‐depth interviews with 90 Mexican migrant smugglers and 45 Central American farmworkers, this article analyzes the three separate elements of trafficking in US agriculture, namely acts, means, and purposes. We conclude that some US employers participate in human trafficking by financing or helping to recruit and transport Mexican and Central American migrants to the US by means of “abuse of a position of vulnerability” for the purposes of involuntary servitude, debt bondage, and sex exploitation.  相似文献   
62.
Psalm 129 depicts the distress of the people in exile. The common understanding is that vv. 6-8 is a lament for the downfall of its present adversaries. This article proves that this is not the meaning of the second half of the Psalm. It contains no appeal to God for salvation or thanksgiving for an ameliorated situation. Verses 6-8 depict the transience of the peoples exilic existence. The psalmist likens the people to the roof-top grass that withers rapidly. The rooftop grass evokes the poverty and the landlessness of the people that compel them to utilize their rooftops to grow crops that yield so little that there is almost nothing to harvest. This situation stands in contrast to the divine blessing of the agriculture in the Land of Israel. The psalmist’s objective is to convey the harsh reality of the exile. He juxtaposes this situation against the much awaited future and against the abundant Divine blessing of the past.  相似文献   
63.
Spiro Mounds was a ceremonial complex located on the Arkansas River, situated in a natural corridor between the Southeast, the Plains, and the Southwestern United States. Considered a quintessential Mississippian site (ad 1000–ad 1450), Spiro was strategically placed as a cultural gateway. Here, dental evidence is presented to aid in the determination of dietary regime and overall population health. The hypothesis regarding the delayed transition to maize agriculture in the Arkansas River Valley will be tested through population comparisons of dental remains. This study will expand the bioarchaeological investigation of a region that has had limited systematic examination. Statistical analysis showed a significant difference between Alluvial, Upland, and Plains environmental zones, and the pattern of dental pathology. Assaults on the dentition at Spiro are moderate. Caries and hypoplasia rates fall just under but approaching those expected for agricultural populations (57% and 49%, respectively). The high number of occlusal caries indicates slower cariogenic destruction and a slower attrition rate. Ante mortem tooth loss was low (18%), with moderate dental attrition (61%). The dental analysis of Spiro Mounds reveals a population with little generalised stress resulting from environmental or sociocultural influences. Comparisons of Spiro to other larger sites in the Mississippian sphere is revealing regarding widespread cultural traditions and their affect on population health; Spiro's unique circumstances give evidence of a population in transition to maize agriculture, but not fully committed to it. Higher status individuals were slower to change from the subsistence strategies that had made them biologically successful. Recent isotope data support this conclusion. The delayed role of maize agriculture at Spiro Mounds, as well as its ideal location within the Mississippian sphere, indicates a different social evolution than other influential Mississippian centres. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
64.
近代以来,农科留美学生引进了美国先进的畜牧兽医科技,促进了我国的畜牧兽医科技近代化进程。中美两国畜牧科技的交流与合作,表现在引进了优良畜禽品种并对国内的畜禽品种进行改良;引进并发展了近代家畜繁殖技术和畜禽饲养管理技术;从发展畜牧业的角度对草原和草地进行调查研究,对牧草进行栽培、选育、贮藏试验,从而揭开了中国近代牧草科技发展的序幕。中美两国兽医科技的交流与合作,则主要侧重于西兽医技术的引进与发展,其主要内容包括动物检疫事业的创建及发展、畜禽传染病的防治与研究等。  相似文献   
65.
三国西晋的越窑青瓷,品质、器类、装饰皆臻于顶峰。同时,生产工艺也达到极高的水准。文章以尼姑婆山窑址为例,从龙窑与窑具、装饰、成型、修坯、上釉、烧成等多个方面,论述了越窑青瓷的生产工艺,认为装饰、模制成型工艺最能代表当时的水平。这些复杂工艺在东晋以后失传,与北人南迁破坏了当地的制瓷传统,从而导致窑业萎缩的历史背景密切相关。  相似文献   
66.
This paper summarizes phytolith analyses from four pre-Columbian agricultural raised-field sites of the coastal savannahs of French Guiana—Savane Grand Macoua, Piliwa, Bois Diable and K-VIII—and carbon isotope analyses from the first-named site. The combined phytolith and 13C isotope analyses evidence the transformation of the landscape from a relatively homogeneous wetland vegetation comprised of a mixture of C4 and C3 plants (the latter including Cyperaceae and other herbaceous monocots such as Marantaceae and Heliconia, Oryzoideae grasses, and other plants typical of frequently flooded areas) to the construction of raised fields that were dominated by C4 plants (maize and other Panicoideae grasses). Our analysis proves the utility of phytoliths for tracing the agricultural history of landscapes, showing that, as in other parts of the Central and South American lowlands, maize (Zea mays) was one important crop cultivated in raised fields. We also estimated the productivity of raised-field agriculture, showing that in combination with other subsistence activities, it certainly had the capacity to sustain sizeable populations.  相似文献   
67.
张卉 《攀登》2010,29(2):107-110
加快现代特色农业的发展是农村经济发展的核心和关键。现代特色农业是海东农业和农村经济发展中最具竞争优势和发展潜力的产业。随着我国农业产业结构调整的不断深化,海东现代特色农业的发展必须立足区情,突出重点,实施农业结构战略性调整,大力培育独具特色的主导产业。  相似文献   
68.
乾卦六龙态的天文含义研究--《左传》"龙纪"历法钩沉   总被引:2,自引:0,他引:2  
《左传》昭公四年的“龙纪”,是上古以苍龙星为历象的太阳历的记载。这个苍龙星星象在《易经》乾卦六爻爻辞中有形象的描述,根据寅月“见龙”、午月“跃龙”等记载,可知其观测年代当在夏代以前。这种借龙“以喻天之阳气”的龙纪历法流传至先秦秦汉,或称“易历”、“气历”;或称“律历”、“甲历”。它以天干记日,十日为旬,六旬为甲,六甲为岁,一岁360日;并通过不记在日序之内的56日的过年日使历年长度略等于回归年长度,从而形成了原始社会晚期一部较实用的历法。  相似文献   
69.
Phytolith analysis is now sufficiently mature to provide an independent source of data in tropical paleoethnobotany and paleoecology. At the same time, ongoing studies of phytoliths from tropical plants and sediments are discovering new applications. There are, to be sure, problems in interpreting prehistoric plant use and paleoecology which cannot be addressed through phytolith analysis; some of the more important ones are listed. Through a review of recent studies in the New World tropics, this paper presents some contributions to, problems of, and prospects for phytolith analysis to inform the archaeological community about such issues as (1) the origins and dispersals of domesticated plants, (2) the development of tropical forest agriculture, (3) the uses of tropical plants in prehistory, and (4) the distribution and composition of past plant communities.  相似文献   
70.
This study analyzes the nitrogen isotope composition of individual amino acids in collagen extracted from human bone samples from the Gaoshan, Yingpanshan, and Xinyicun sites in Sichuan, where the isotope baseline is unavailable or incomparable with the isotopic data derived from human remains. It aims to understand the food compositions of the inhabitants at these sites, spanning the period from the late Neolithic to the middle Bronze Age, during which time agriculture and domestication of animals were introduced to the region and became increasingly important. The δ15N values of two amino acids, phenylalanine (δ15NPhe) and glutamic acid (δ15NGlu), indicate that the peoples on the Chengdu Plain mainly consumed terrestrial foods. The contribution of aquatic resources to their diet was limited. A possible explanation for the low dependence on aquatic foods is that the developed agriculture and domestication of animals offered sufficient foods. Such subsistence economies and dietary patterns were shaped in the early Baodun period (ca. 2,500–2000 BCE) at the latest and did not seem to change when transiting to the Bronze Age. This study also assesses the significance of these subsistence practices in supporting the social development of the Chengdu Plain.  相似文献   
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