984 resultados para Migration. Selectivity. Income Differential


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We investigated the relationship between the fusion selectivity of the envelope glycoprotein (env) and the tropism of different human immunodeficiency virus type 1 (HIV-1) isolates for CD4+ human T-cell lines vs. primary macrophages. Recombinant vaccinia viruses were prepared encoding the envs from several well-characterized HIV-1 isolates with distinct cytotropisms. Cells expressing the recombinant envs were mixed with various CD4+ partner cell types; cell fusion was monitored by a quantitative reporter gene assay and by syncytia formation. With CD4+ continuous cell lines as partners (T-cell lines, HeLa cells expressing recombinant CD4), efficient fusion occurred with the envs from T-cell line-tropic isolates (IIIB, LAV, SF2, and RF) but not with the envs from macrophage-tropic isolates (JR-FL, SF162, ADA, and Ba-L). The opposite selectivity pattern was observed with primary macrophages as cell partners; stronger fusion occurred with the envs from the macrophage-tropic than from the T-cell line-tropic isolates. All the envs showed fusion activity with peripheral blood mononuclear cells as partners, consistent with the ability of this cell population to support replication of all the corresponding HIV-1 isolates. These fusion selectivities were maintained irrespective of the cell type used to express env, thereby excluding a role for differential host cell modification. We conclude that the intrinsic fusion selectivity of env plays a major role in the tropism of a HIV-1 isolate for infection of CD4+ T-cell lines vs. primary macrophages, presumably by determining the selectivity of virus entry and cell fusion.

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This paper deals with the determinants of labour out-migration from agriculture across 149 EU regions over the 1990–2008 period. The central aim is to shed light on the role played by payments from the common agricultural policy (CAP) on this important adjustment process. Using static and dynamic panel data estimators, we show that standard neoclassical drivers, like relative income and the relative labour share, represent significant determinants of the intersectoral migration of agricultural labour. Overall, CAP payments contributed significantly to job creation in agriculture, although the magnitude of the economic effect was rather moderate. We also find that pillar I subsidies exerted an effect approximately two times greater than that of pillar II payments.

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In order to stabilise and improve their income situation, rural households are strongly encouraged to diversify their activities both within and outside the agricultural sector. Often, however, this advice is only moderately pursued. This paper addresses issues of rural household income diversification in the case of Poland. It investigates returns from rural household income strategies using propensity score matching methods and extensive datasets spanning 1998-2008. Results suggest that returns from combining farm and off-farm activities were lower than returns from concentrating on farming or on self-employment outside agriculture. This differential is stable over time although returns from diversification have relatively improved after Poland’s accession to the EU. This is also visible in the fact that since 2006 returns from combining farm and off-farm activities have evened with returns from relying solely on hired off-farm labour, thus smoothing the difference observed before the accession. Further, over the analysed period, households pursuing the diversification strategy performed better than those relying solely on unearned income. Finally, in general, the income in households combining farm and off-farm activities was higher than in those combining two off-farm income sources.

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requirements for Filipino performing artists, effectively closing this migration channel. I employ a difference-in-differences estimation strategy using the share of performing artists at baseline in each Philippine province as a continuous policy variable. International migration falls in response to the policy change by 1.2%. The effect on international migration is larger than the policy change itself would suggest, indicating the importance of spillovers across migrant occupations. Domestically, more children are employed, and adults are more likely to be unemployed or engaged in short-term work.

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Little is known of the structure of the international migration of skilled health professionals. Accelerated migration of doctors and nurses from the Pacific island states of Fiji, Samoa and Tonga to the Pacific periphery is part of the globalization of health care. The findings from a recent survey of 251 doctors and nurses from the three island countries are reported here. Key determinants of both present migration status and future migration intentions were analyzed using econometric methods. Nurses' and doctors' propensities to migrate are influenced by both income and non-income factors, including ownership of businesses and houses. Migrants also tend to have more close relatives overseas, to have trained there, and so experienced superior working conditions. Migration propensities vary between countries, and between nurses and doctors within countries. Tongan nurses have a higher propensity to migrate, mainly because of greater relative earnings differentials, but are also more likely to return home. The role of kinship ties, relative income differentials and working conditions is evident in other developing country contexts. Remittances and return migration, alongside business investment, bring some benefits to compensate for the skill drain. National development policies should focus on encouraging return migration, alongside retention and recruitment, but are unlikely to prevent out migration. (C) 2003 Elsevier Ltd. All rights reserved.

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Examines the European Court of Justice ruling in Test Claimants in the FII Group Litigation v Inland Revenue Commissioners (C-35/11) on whether the differential tax treatment of domestic and foreign-sourced dividends in the UK was compatible with the freedom of establishment and free movement of capital principles. Outlines its guidance on how to assess this compatibility. Considers the ruling's implications for the UK tax system, the relationship between tax sovereignty and the internal market and the third-country dimension of the free movement of capital principle.

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Pd(II) and Pd(0) catalysts supported onto titanate nanotubes (H2Ti3O7) were prepared by an ion-exchange technique. The catalysts are characterised by narrow size distribution of metal nanoparticles on the external surface of the nanotubes. Pd(II) catalysts show high selectivity toward double-bond migration reaction versus hydrogenation in linear olefins. The catalytic activity exhibits a volcano-type dependence on the metal loading, with the maximum activity observed at ca. 8 wt%. The Pd(II) was shown to be rapidly reduced to Pd(0) by appropriate choice of solvent. Prereduced Pd(0) catalysts were found to be less active toward double-bond migration and more selective toward hydrogenation. The DBM reaction was faster in protic solvents, such as methanol or ethanol. © 2006 Elsevier Inc. All rights reserved.

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The presence of inflammatory cells and MPO (myeloperoxidase) in the arterial wall after vascular injury could increase neointima formation by modification of phospholipids. The present study investigates how these phospholipids, in particular oxidized and chlorinated species, are altered within injured vessels and how they affect VSMC (vascular smooth muscle cell) remodelling processes. Vascular injury was induced in C57BL/6 mice and high fat-fed ApoE-/- (apolipoprotein E) mice by wire denudation and ligation of the left carotid artery (LCA). Neointimal and medial composition was assessed using immunohistochemistry and ESI-MS. Primary rabbit aortic SMCs (smooth muscle cells) were utilized to examine the effects of modified lipids on VSMC proliferation, viability and migration at a cellular level. Neointimal area, measured as intima-to-media ratio, was significantly larger in wire-injured ApoE-/- mice (3.62±0.49 compared with 0.83±0.25 in C57BL/6 mice, n=3) and there was increased oxidized low-density lipoprotein (oxLDL) infiltration and elevated plasma MPO levels. Relative increases in lysophosphatidylcholines and unsaturated phosphatidylcholines (PCs) were also observed in wire-injured ApoE-/- carotid arteries. Chlorinated lipids had no effect on VSMC proliferation, viability or migration whereas chronic incubation with oxidized phospholipids stimulated proliferation in the presence of fetal calf serum [154.8±14.2% of viable cells at 1 μM PGPC (1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphocholine) compared with control, n=6]. In conclusion, ApoE-/- mice with an inflammatory phenotype develop more neointima in wire-injured arteries and accumulation of oxidized lipids in the vessel wall may propagate this effect.

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The 1996 welfare reform, for the first time in U.S. history, set a five-year residence requirement for immigrants to be eligible for federal welfare benefits. This dissertation assessed the impact of the 1996 welfare reform, specifically the immigrant provisions, on the economic well-being of low-income immigrants. This dissertation also explored the roles that migration selection theory and social capital theory play in the economic well-being of low-income immigrants. ^ This dissertation was based on an analysis of the March 1995, March 2002, and March 2006 Annual Demographic Supplement Files of the Current Population Survey (CPS). Both logistic regression and multiple regression were used to analyze economic well-being, comparing low-income immigrants with low-income citizens. Economic well-being was measured in the current survey year and the year before on the following variables: employment status, full-time status (35 or more hours per week), the number of weeks worked, and the total annual wage or salary.^ The major findings reported in this dissertation were that low-income immigrants had advantages over low-income citizens in the labor market. This may be due to immigrants' stronger motivation to obtain success, consistent with migration selection theory. Also, this research suggested that immigrant provisions had not ameliorated employment outcomes of low-income immigrants as policymakers may have expected.^ The study also confirmed the role of social capital in advancing the economic well-being of qualified immigrants. Ultimately, this dissertation contributed to our understanding of low-income immigrants in the U.S. The study questioned the claim that immigrants are attracted to the U.S. by welfare benefits. This dissertation suggested that immigrants come to the U.S., to a large extent, to pursue the goal of upward mobility. Consequently, immigrants may employ greater initiative and work harder than native-born Americans.^

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Oesophageal cancer is an aggressive tumour which responds poorly to both chemotherapy and radiation therapy and has a poor prognosis. Thus, a greater understanding of the biology of oesophageal cancer is needed in order to identify novel therapeutic targets. Among these targets p38 MAPK isoforms are becoming increasingly important for a variety of cellular functions. The physiological functions of p38α and -β are now well documented in contrast to -γ and -δ which are comparatively under-studied and ill-defined. A major obstacle to deciphering the role(s) of the latter two p38 isoforms is the lack of specific chemical activators and inhibitors. In this study, we analysed p38 MAPK isoform expression in oesophageal cancer cell lines as well as human normal and tumour tissue. We observed specifically differential p38δ expression. The role(s) of p38δ and active (phosphorylated) p38δ (p-p38δ) in oesophageal squamous cell carcinoma (OESCC) was delineated using wild-type p38δ as well as active p-p38δ, generated by fusing p38δ to its upstream activator MKK6b(E) via a decapeptide (Gly-Glu)5 linker. OESCC cell lines which are p38δ-negative (KE-3 and -8) grew more quickly than cell lines (KE-6 and -10) which express endogenous p38δ. Re-introduction of p38δ resulted in a time-dependent decrease in OESCC cell proliferation which was exacerbated with p-p38δ. In addition, we observed that p38δ and p-p38δ negatively regulated OESCC cell migration in vitro. Finally both p38δ and p-p38δ altered OESCC anchorage-independent growth. Our results suggest that p38δ and p-p38δ have a role in the suppression of OESCC. Our research may provide a new potential target for the treatment of oesophageal cancer.

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This article analyses the motivations for return migration among the Ecuadorians and Bolivians who, after living in Spain, returned to their countries of origin during the economic crisis that started in 2008. From the analysis of 22 interviews in-depth which took place in Ecuador and 38 in Bolivia to women, men and young people from migrant families, this decision-making process is shown to be embedded into a gendered dynamics of relationships. Particular detail is given to affective and economic elements that had an influence on the decision to return, as well as to the strategies deployed to project their readjustment back in origin. Males and females occupy differential positions within the family, work and social circle, their expectations being built in a gendered manner. Despite the fact migration has brought women greater economic power within the family group, their reintegration upon return redefines their role as main managers in the household and the dynamics that allow their social reproduction. Men, for their part, aspire to refresh their role as providers in spite of their frail labour position upon return. Social mobility for females is passed on through generations by a strong investment on education for their daughters and sons, while for males this mobility revolves around setting up family businesses and around their demonstrative abilities.

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This paper analyzes the impact of Spain’s economic crisis on social reproduction strategies of Ecuadorian migrant families in Madrid and Quito. The paper analyzes circular migration experiences and more permanent returns to Ecuador. I argue that these strategies and migrants' greater or lesser capabilities to move between different migration destinations show significant gender differences. On the one hand, men and women make a differential use of their migratory status to deploy transnational strategies and expand their mobility. On the other hand, migrants’ degree of mobility and flexibility with regard to the labor market and transnational social reproduction are derivative of a specific gendered order and sexual division of labor.

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Doutoramento em Economia.

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The essential oil from the leaves of Ocimum kilimandscharicum (EOOK), collected in Dourados-MS, was investigated for anticancer, anti-inflammatory and antioxidant activity and chemical composition. The essential oil was extracted by hydrodistillation, and the chemical composition was performed by gas chromatography-mass spectrometry. The essential oil was evaluated for free radical-scavenging activity using the DPPH assay and was tested in an anticancer assay against ten human cancer cell lines. The response parameter (GI50) was calculated for the cell lines tested. The anti-inflammatory activity was evaluated using carrageenan-induced pleurisy in mice. The chemical composition showed 45 components with a predominance of monoterpenes, such as camphor (51.81%), 1,8 cineole (20.13%) and limonene (11.23%). The EOOK exhibited potent free radical-scavenging activity by the DPPH assay with a GI50 of 8.31 μg/ml. The major constituents, pure camphor (IC50=12.56 μg/ml) and mixture of the limonene: 1, 8 cineole (IC50=23.25 μg/ml) displayed a potent activity. The oral administration of EOOK (at 30 and 100 mg kg(-1)), as well as the pure camphor or a mixture of 1,8 cineole with limonene, significantly inhibited the carrageenan (Cg) induced pleurisy, reducing the migration of total leukocytes in mice by 82 ± 4% (30 mg kg(-1) of EOOK), 95 ± 4% (100 mg kg(-1) of EOOK), 83 ± 9% (camphor) and 80 ± 5% (mixture of 1,8 cineole:limonene 1:1). In vitro cytotoxicity screening against a human ovarian cancer cell line displayed high selectivity and potent anticancer activity with GI50=31.90 mg ml(-1). This work describes the anti-inflammatory, anticancer and antioxidant effects of EOOK for the first time. The essential oil exhibited marked anti-inflammatory, antioxidant and anticancer effects, an effect that can be attributed the presence of majorital compounds, and the response profiles from chemical composition differed from other oils collected in different locales.

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Palpable mass is a common complaint presented to the breast surgeon. It is very uncommon for patients to report breast mass associated with palpable masses in other superficial structures. When these masses are related to systemic granulomatous diseases, the diagnosis and initiation of specific therapy can be challenging. The purpose of this paper is to report a case initially assessed by the breast surgeon and ultimately diagnosed as granulomatous variant of T-cell lymphoma, and discuss the main systemic granulomatous diseases associated with palpable masses involving the breast.