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121.
Malika Abdelali-Martini Patricia Goldey Gwyn Jones Elizabeth Bailey 《The Journal of peasant studies》2013,40(2):71-94
Smallholdings in the rural areas of northwest Syria are a result of land fragmentation that is due to inheritance. Because of rapid population growth combined with land fragmentation, these smallholdings are increasing and cannot sustain the rural households whose sizes and needs are also increasing rapidly This situation has led to increasing numbers of males migrating to urban areas in Syria and to neighbouring countries looking for work opportunities. In addition, recent agricultural intensification trends seem to have led to the emergence of a waged labour force which, in the absence of male workers owing to significant rates of migration, is now predominantly female. Agricultural labour use depends upon household characteristics and resources (type of labour used, gender of labour waged/exchanged/familial). The article attempts to present a comprehensive analysis of household labour use in distinctive farming systems in one region of Syria that has undergone great change in recent decades, and examines the changes in the composition of the agricultural labour force. Secondary information, rapid ural appraisals and formal farm surveys were used to gather information on the households in a study area where different farming systems coexist. The results show that the decrease in landholding size, the resulting male migration, and land intensification have resulted in the expansion offemale labour in agriculturalproduction, which has been termed in this research a 'feminization of agricultural labour'. This suggests that agricultural research and extension services will have to work more with women farmers and farm workers, seek their wisdom and involve them in technology and transfer. This is not easy in conservative societies but requires research and extension institutions to take this reality into consideration in their programmes. 相似文献
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Michael D. Schulman Patricia M. Garrett Barbara A. Newman 《The Journal of peasant studies》2013,40(4):523-541
This article addresses theoretical issues concerning differentiation and class formation using North American data. It explores how socio‐economic characteristics vary and impact survival in agriculture. The study is based on panel data collected from a sample of smallholders in three Piedmont North Carolina counties. Factor analysis reveals five major dimensions of differentiation: scale, household labour, off‐farm family labour and income, demographic characteristics, and land tenure. An index of propensity to survive in agriculture, constructed from three waves of panel data is regressed upon five indices measuring the underlying dimensions of differentiation. Land tenure manifests a statistically significant net effect on survival in agriculture. These empirical results support theoretical arguments in favour of integrating analyses of socio‐economic and demographic differentiation in the study of agricultural enterprises. 相似文献
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Catarina Ochôa Rodrigues Maria Teresa Ferreira Vítor Matos David Gonçalves 《Science & justice》2021,61(1):26-36
The true impact of heat-induced changes in human bone regarding their sex estimation has not been comprehensively documented having a potentially negative impact on forensic anthropology. The objective of this paper was to evaluate how heat exposure affects sex estimation based on both morphological and metric features. The study focused in both low-to-medium intensity burns and high intensity burns. Selected sexually dimorphic features were analysed in 51 experimentally burnt skeletons from the 21st Century Identified Skeletal Collection. Bones were burnt to maximum temperatures between 450 °C and 1050 °C achieved after 75 to 257 min. Morphological methods tested in this study comprised the recommendations for hipbone features from Buikstra and Ubelaker (1994) and from Bruzek (2002). On the other hand, metric references tested here were the ones from Wasterlain (2000), Curate et al. (2016) and Gonçalves et al. (2013) focused on the humerus, femur, calcaneus and talus. Agreement was tested with Gwet’s AC1 test and was further assessed by calculating the relative amount of perfect agreements. Results demonstrated that heat-induced changes affected not only the scoring of morphological features burnt at high temperatures but also the scoring of features burnt at lower intensities. On the other hand, metric features were only considerably affected in high intensity burns, no major changes being documented for low-to-medium intensity burns. For low-to-medium intensity burns, the Bruzek and Curate et al. methods revealed a better agreement between the pre- and post-burning scores. For high intensity burns, better agreement was obtained by using the Bruzek (2002) and Gonçalves et al. (2013) methods. As expected, heat-induced warping, fracture and metric change had a major impact on the pre- and post-observations’ agreement. Contrary to what has been systematically assumed over the years, this impact is also quite substantial in bones burnt at low-to-medium burn intensities so caution is advised during the analysis of this kind of burnt skeletal material. 相似文献
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THE CURRENTS BENEATH THE “RISING TIDE” OF SCHOOL CHOICE: AN ANALYSIS OF STUDENT ENROLLMENT FLOWS IN THE CHICAGO PUBLIC SCHOOLS 下载免费PDF全文
Roger Guimerà Uri Wilensky Luís A. Nunes Amaral 《Journal of policy analysis and management》2015,34(2):358-377
Existing research highlights that families face geographic, social, and psychological constraints that may limit the extent to which competition can take hold in school choice programs. In this paper, we address the implications of such findings by creating a network of student flows from 11 cohorts of eighth‐grade students in the Chicago Public Schools (CPS). We applied a custom algorithm to group together schools with similar sending and receiving patterns, and calculated the difference in mean achievement between a student's attended and assigned high schools. For all identified school groupings, we found that the students were on average moving to higher achieving schools. We also found that the movement toward higher achieving schools of the top achievement quartile of students was over twice as large as that of the bottom quartile, but that the flows of both the highest and lowest achieving student quartiles were toward higher achieving destinations. Our results suggest that student movements in CPS between the years of 2001 to 2005 were consistent with creating market pressure for improvement as well as increasing segregation by achievement. However, further research into how schools responded to those movements is required to make inferences about the level or consequences of competition generated by choice‐related reforms during that time. 相似文献
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