955 resultados para International Labor Migration
Resumo:
This paper uses data collected from migrants' wives in the Nyeri district of Kenya. The main objective is to determine whether migration and remittances contribute to the development of agriculture. Our results suggest that most migrants are pushed out of rural areas, belong to the group of low-paid workers in urban areas, send little and irregular remittances to their wives back in rural areas and that these remittances are mainly used for consumption purposes and do not contribute to any significant development in agriculture. Our results also indicate that altruism or social obligation might be the main reason for migrants sending remittances back to their rural wives.
Resumo:
We report here the existence of a novel subset of langerin (CD207)-positive, immature dendritic cells (DCs) (CD83(neg)) abundantly infiltrating Epstein Barr virus (EBV)-infected areas in tonsil, Hodgkin lymphoma and nasopharyngeal carcinoma. These CD207(+) DCs differ from conventional epidermal Langerhans cells in their lack of CD1a and CCR6 and their unusual tissue localization. CD207(+) DC infiltration strongly correlates with EBV infection because it was neither detected in EBV negative specimens nor in tissues infected with other human viruses. These immature DCs might represent good candidates for induction of the EBV-specific immune response.
Resumo:
The humpback whales that migrate along the east coast of Australia were hunted to near-extinction in the 1950s and early 1960s. Two independent series of land-based surveys conducted over the last 25 years during the whales’ northward migration along the Australian coastline have demonstrated a rapid increase in the size of the population. In 2004 we conducted a survey of the migratory population as a continuation of these series of surveys. Two methods of data analysis were used in line with the previous surveys, both for calculation of absolute and relative abundance. We consider the best estimates for 2004 to be 7,090 ± 660 (95% CI) whales with an annual rate of increase of 10.6 ± 0.5% (95% CI) for 1987 – 2004. The rate of increase agrees with those previously obtained for this population and demonstrates the continuation of a strong post-exploitation recovery. While there are still some uncertainties concerning the absolute abundance estimate and structure of this population, the rate of annual increase should be independent of these and highly robust.
Resumo:
Growing economic globalisation by extending the operation of markets is a two-edged sword as far as nature conservation is concerned. In some circumstances, it threatens the conservation of nature and in other cases, it provides economic incentives that foster the conservation of biodiversity. This article shows how global policy directions have altered in that regard. Initially the World Conservation Union (IUCN) favoured bans on trade in endangered species. This view was enshrined in the Convention on International Trade in Endangered Species (CITES). Subsequently, with the upsurge of support for market-based economic liberalism, IUCN recognised that economic and market incentives, if linked to appropriate property rights, could foster biodiversity conservation. This is reflected in the International Convention on Biological Diversity. While there is conflict between this convention and CITES, its extent has been exaggerated. As explained, in certain cases, trade restrictions of the type adopted in CITES are appropriate for nature conservation whereas the market-oriented policy of the Convention on Biological Diversity can be effective in some different situations. Whether or not the extension of markets in wildlife and wildlife products and growing economic globalisation favours nature conservation varies according to the circumstances.
Resumo:
Paracoccidioidomycosis, a debilitating pulmonary mycosis, is caused by the dimorphic fungus Paracoccidioides brasiliensis. The infection results in the formation of granulomas containing viable yeast cells that are the fungal sources for disease reactivation. Because CD4(+)CD25(+) regulatory T cells (Tregs) are in the lesions of patients with paracoccidioidomycosis, the migration of Treg cells is dependent on the axis chemokine-chemokine receptors, and CCR5 ligands are produced in P. brasiliensis-induced lesions, we investigated the role of CCR5 in the control of the infection. The results showed that CCR5(-/-) mice are more efficient in controlling fungal growth and dissemination and exhibited smaller granulomas than wild-type (WT) mice. In the absence of CCR5, the percentage of CD4(+)CD25(+) T cells expressing Foxp3, glucocorticoid-induced TNFR (GITR), CD103, CD45(low), and CTLA-4 in the granulomas was significantly decreased. Interestingly, P. brasiliensis infection resulted in an absence of T cell proliferation in response to Con A in WT but not CCR5(-/-) mice that was abrogated by anti-CTLA-4 mAb and anti-GITR mAb. Moreover, the adoptive transfer of CD4(+)CD25(+) but not CD4(+)CD25(-) T cells from infected WT to infected CCR5(-/-) mice resulted in a significant increase in fungal load. Overall, CCR5 is a key receptor for the migration of Treg cells to the site of P. brasiliensis infections leading to down-modulation of effector immune response and the long-term presence of the fungus in the granulomas. Thus, a tight control of Treg cell migration to the granulomatous lesions could be an important mechanism for avoiding exacerbation and reactivation of the disease.
Resumo:
The need for methods of indirectly estimating migration flows is particularly important in developing countries, where migration data are often incomplete and inaccurate. This paper focuses on the use of an indirect internal migration estimation method applied to Mexican and Indonesian census data. It shows that the mobility propensities of infants can be used to infer the corresponding propensities of all other age groups. However, the promise of this method is reduced in instances of inadequate data, and great care must be taken to identify outlying values in the data and to correct obviously erroneous patterns. Future work increasingly will be directed to this issue.