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61.
Land grabbing has gained momentum in Latin America and the Caribbean during the past decade. The phenomenon has taken different forms and character as compared to processes that occur in other regions of the world, especially Africa. It puts into question some of the assumptions in the emerging literature on land grabbing, suggesting these are too food-centered/too food crisis-centered, too land-centred, too centred on new global food regime players – China, South Korea, Gulf States and India – and too centred on Africa. There are four key mechanisms through which land grabbing in Latin American and the Caribbean has been carried out: food security initiatives, energy/fuel security ventures, other climate change mitigation strategies, and recent demands for resources from newer hubs of global capital. The hallmark of land grabbing in the region is its intra-regional character: the key investors are (Trans-)Latin American companies, often in alliance with international capital and the central state. Initial evidence suggests that recent land investments have consolidated the earlier trend away from (re)distributive land policies in most countries in the region, and are likely to result in widespread reconcentration of land and capital.  相似文献   
62.
Using an innovative survey of protest participants and nonparticipants from five major street demonstrations in Mexico City in 2011 and 2012, this study tests the assumption that influences on protest participation vary across different types of events; namely, ritual demonstrations and reactive protests. The comparison is based on two assumptions: that these are two of the dominant forms of protest in contemporary Latin America, and that specifying the context for different types of social movement participation provides a better understanding of the individual mobilization process for groups seeking to defend their rights or gain new benefits. The comparative analyses reveal some crucial differences. Political interest and previous political experience are more influential in the decision to take part in reactive demonstrations. For ritual demonstrations, the decision to participate tends to be driven more by personal and organizational connections.  相似文献   
63.
宁夏羊胃肠道线虫对现行驱虫药的抗药性调查   总被引:2,自引:2,他引:2  
采用粪便虫卵减少试验对宁夏地区所属灵武、贺兰、盐池、吴忠、中宁、中卫、永宁和银川市郊8个县(市)的12个绵羊场、6个山羊场进行了丙硫苯咪唑和阿维菌素抗药性的随机调查。结果表明:在用丙硫苯咪唑调查的10个绵羊场和6个山羊场中,虫卵减少率在95%以下和95%的置信域下限在90%以下的有山羊场2个、绵羊场2个,证明对丙硫苯咪唑有抗药性;1个绵羊场和1个山羊场的虫卵减少率是96.3%、95.9%,但95%置信域的下限在90%以下,具有抗药性可疑;山羊群中丙硫苯咪唑的抗药性为33.3%,绵羊群为20.0%。用同样的方法调查了1个山羊场和5个绵羊场(其中有4个羊场曾执行了丙硫苯咪唑的试验),查出1个山羊场和1个绵羊场对阿维菌素具有抗药性可疑,其虫卵减少率分别为97.3%和95.5%,置信域下限在90%以下。揭示了宁夏地区羊消化道线虫对现行驱虫药的抗药状态,为今后防治提供了依据。  相似文献   
64.
Gene and genotype frequencies in relation to the D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, and D7S820 loci were determined in a sample of 290 unrelated individuals (204 Caucasians and 86 mulattoes) living in the city of S?o Paulo, Brazil. The sex test Amelogenin was also performed in all subjects from our sample, revealing the expected sex in all instances. Allele frequency data obtained from the analysis of these samples were in the usual range of other population groups with similar racial background. In the sample of Caucasian individuals, panmictic proportions were ruled out in relation to TPOX and CSF1PO loci, but only in the latter was the overall frequency of heterozygotes significantly less than expected. In the sample of mulattoes, Hardy-Weinberg proportions were rejected in relation to FGA and CSF1PO loci, but in no instance were the overall numbers of heterozygotes different from the corresponding expected ones under panmixia. Taking into account all this and also the number of tests performed, the degree of genetic heterogeneity of Brazilian populations, and the critical level reached by the significant results (1% < alpha<5%), the departures from panmixia here observed can be considered to be negligible in altering significantly biologic relationship odds calculated under the assumption of random matings.  相似文献   
65.
66.
Research into maximizing the speed, precision, and reliability of estimating the postmortem interval (PMI) has been a recurring object of investigation and methodologies based on the vitreous humor (VH) have provided good results. However, contamination from causes not readily apparent, such as blood, can occur, and thus lead not only to an erroneous estimation of PMI, but also interfere with the correct identification of other substances in the VH. We have developed a flow cytometry method which quantifies blood contamination and is able to detect erythrocytes in 1:750,000 dilution of contaminated VH which affects the results of hypoxanthine. It is an improvement on the previous more complex mass spectrometry method, being faster, more sensitive, and readily available. As such, it could be proposed for the rapid screening of appropriate samples by detecting and eliminating blood contaminated samples from PMI estimation.  相似文献   
67.
68.
我国乡村干部的腐败问题及其治理对策研究   总被引:4,自引:0,他引:4  
乡村干部处在农村工作的第一线,是农业生产和农村社会活动的组织者和领导者,是党的路线、方针、政策在农村的宣传者、推动者和执行者,是团结带领农民群众建设社会主义新农村的带头人.近年来中国乡村干部腐败问题越来越严重,在有些地方已成为"常态".腐败案件越来越多,并且呈现逐年上升的趋势,引起了广大农民群众的强烈不满.从分析乡村干部腐败案件入手,揭示了造成乡村干部腐败的五个因素:乡村干部权力观的严重扭曲,手中掌握的权力"含金量"高,权力运行缺乏有效监督,腐败的预期成本低,以及财务管理混乱等.指出了乡村干部腐败的严重性:乡村干部腐败损害了党和政府的形象,侵害了农民群众的切身利益,制约了农村集体经济的发展,破坏了农村的社会稳定.最后,有针对性地提出了治理乡村干部腐败的对策.  相似文献   
69.
70.
The authors evaluated the usefulness of the postmortem biochemical analysis of ionic ratios in different parts of the heart and their relation to cardiac damage caused by chest trauma, as observed by anatomopathologic study. Fifty-nine 59 cases were studied, selected from routine necropsies, and samples were taken from different sites of cardiac tissue. The cause of death was trauma in 40 cases and nontraumatic causes in 19 cases. The object of this study was to analyze the levels of Na+, K+, Ca+2, Mg+2, and Zn+2 in different zones of the heart, and the relationship between intracellular and extracellular ion ratios and the different causes of death and any anatomopathologic alterations observed. The biochemical tests revealed a possible relation between the ionic values and cause of death. Alterations in cell membrane permeability and corresponding modification of the ionic ratios were produced earlier than histologic alterations, which need longer to establish themselves whether or not they follow a traumatic process.  相似文献   
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