857 resultados para Migration flows
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics
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Dissertation presented to Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa for obtaining the master degree in Membrane Engineering
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Dissertação para obtenção do Grau de Mestre em Engenharia Civil – Perfil de Estruturas
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Fundação para a Ciência e a Tecnologia - SFRH/BD/42848/2008, através do Programa MIT_Portugal em Sistemas de Bioengenharia; projectos PTDC/SAUNEU/104415/2008 e Projecto ref. 96542 da Fundação Caloust Gulbenkian
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Does return migration affect entrepreneurship? This question has important implications for the debate on the economic development effects of migration for origin countries. The existing literature has, however, not addressed how the estimation of the impact of return migration on entrepreneurship is affected by double unobservable migrant self-selection, both at the initial outward migration and at the final inward return migration stages. This paper uses a representative household survey conducted in Mozambique in order to address this research question. We exploit variation provided by displacement caused by civil war in Mozambique, as well as social unrest and other shocks in migrant destination countries. The results lend support to negative unobservable self-selection at both and each of the initial and return stages of migration, which results in an under-estimation of the effects of return migration on entrepreneurial outcomes when using a ‘naïve’ estimator not controlling for self-selection. Indeed, ‘naïve’ estimates point to a 13 pp increase in the probability of owning a business when there is a return migrant in the household relative to non-migrants only, whereas excluding the double effect of unobservable self-selection, this effect becomes significantly larger - between 24 pp and 29 pp, depending on the method of estimation and source of variation used.
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Crisis-affected communities and global organizations for international aid are becoming increasingly digital as consequence geotechnology popularity. Humanitarian sector changed in profound ways by adopting new technical approach to obtain information from area with difficult geographical or political access. Since 2011, turkey is hosting a growing number of Syrian refugees along southeastern region. Turkish policy of hosting them in camps and the difficulty created by governors to international aid group expeditions to get information, made such international organizations to investigate and adopt other approach in order to obtain information needed. They intensified its remote sensing approach. However, the majority of studies used very high-resolution satellite imagery (VHRSI). The study area is extensive and the temporal resolution of VHRSI is low, besides it is infeasible only using these sensors as unique approach for the whole area. The focus of this research, aims to investigate the potentialities of mid-resolution imagery (here only Landsat) to obtain information from region in crisis (here, southeastern Turkey) through a new web-based platform called Google Earth Engine (GEE). Hereby it is also intended to verify GEE currently reliability once the Application Programming Interface (API) is still in beta version. The finds here shows that the basic functions are trustworthy. Results pointed out that Landsat can recognize change in the spectral resolution clearly only for the first settlement. The ongoing modifications vary for each case. Overall, Landsat demonstrated high limitations, but need more investigations and may be used, with restriction, as a support of VHRSI.
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Double Degree. A Work Project, presented as part of the requirements for the Award of a Master’s Degree in Management from NOVA – School of Business and Economics and a Masters Degree in Economics from Louvain School of Management
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Are return migrants more productive than non-migrants? If so, is it a causal effect or simply self-selection? Existing literature has not reached a consensus on the role of return migration for origin countries. To answer these research questions, an empirical analysis was performed based on household data collected in Cape Verde. One of the most common identification problems in the migration literature is the presence of migrant self-selection. In order to disentangle potential selection bias, we use instrumental variable estimation using variation provided by unemployment rates in migrant destination countries, which is compared with OLS and Nearest Neighbor Matching (NNM) methods. The results using the instrumental variable approach provide evidence of labour income gains due to return migration, while OLS underestimates the coefficient of interest. This bias points towards negative self-selection of return migrants on unobserved characteristics, although the different estimates cannot be distinguished statistically. Interestingly, migration duration and occupational changes after migration do not seem to influence post-migration income. There is weak evidence that return migrants from the United States have higher income gains caused by migration than the ones who returned from Portugal.
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Taking a Media Anthropology’s approach to dynamics of mediated selfrepresentation in migratory contexts, this thesis starts by mapping radio initiatives produced by, for and/or with migrants in Portugal. To further explore dynamics of support of initial settlement in the country, community-making, cultural reproduction, and transnational connectivity - found both in the mapping stage and the minority media literature (e.g. Kosnick, 2007; Rigoni & Saitta, 2012; Silverstone & Georgiou, 2005) - a case study was selected: the station awarded with the first bilingual license in Portugal. The station in question caters largely to the British population presenting themselves as “expats” and residing in the Algarve. The ethnographic strategy to research it consisted of “following the radio” (Marcus, 1995) beyond the station and into the events and establishments it announces on air, so as to relate production and consumption realms. The leading research question asks how does locally produced radio play into “expats” processes of management of cultural identity – and what are the specificities of its role? Drawing on conceptualizations of lifestyle migration (Benson & O’Reilly, 2009), production of locality (Appadurai 1996) and the public sphere (Butsch, 2007; Calhoun & et al, 1992; Dahlgren, 2006), this thesis contributes to valuing radio as a productive gateway to research migrants’ construction of belonging, to inscribe a counterpoint in the field of minority media, and to debate conceptualizations of migratory categories and flows. Specifically, this thesis argues that the station fulfills similar roles to other minority radio initiatives but in ways that are specific to the population being catered to. Namely, unlike other minority stations, radio facilitates the process of transitioning between categories along on a continuum linking tourists and migrants. It also reflects and participates in strategies of reterritorialization that rest on functional and partial modes of incorporation. While contributing to sustain a translocality (Appadurai, 1996) it indexes and fosters a stance of connection that is symbolically and materially connected to the UK and other “neighborhoods” but is, simultaneously, oriented to engaging with the Algarve as “home”. Yet, besides reifying a British cultural identity, radio’s oral, repetitive and ephemeral discourse particularly trivializes the reproduction of an ambivalent stance of connection with place that is shared by other “expats”. This dynamic is related to migratory projects driven by social imaginaries fostered by international media that stimulate the search for idealized ways of living, which the radio associates with the Algarve. While recurrently localizing and validating the narrative projecting an idealized “good life”, radio amplifies dynamics among migrants that seem to reaffirm the migratory move as a good choice.
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This thesis explores the development and employment of microfluidic devices as a tool for studying the effect of the surrounding environment on embryonic stem cells during the migration phenomena. Different single-cell microchips were designed and manufactured to study mouse embryonic fibroblasts (MEFs) migration towards an environmental variation (increase of serum concentration in the culture medium) that was expected to function as a motility stimuli. Considering the experimental, cells were injected into the microchips chambers and individually isolated by dedicated cell traps with view to a single-cell analysis. Once fribroblasts were attached to the surface, culture medium with an increased serum level was subsequently injected in an adjacent chamber to promote the formation of a serum concentration gradient. The gradient established between the chambers could be sensed by the fibroblasts and thus triggered the cells mobilization towards and in the direction of the richer serum medium. Additionally, the experiment allowed the observation of MEFs’ structural reorganization when migrating through micro-tunnels containing widths below the cell size, suggesting a cytoskeleton rearrangement on account of the nutritional stimulus introduced. Furthermore, results indicate that fibronectin promotes MEFs adhesion to the substrate and that MEFs migration is characterized as haptotactic.
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Os séculos XX e XXI corresponderam ao agudizar de processos globalizantes potenciados pelas novas tecnologias, quer no âmbito comunicacional, quer industrial, sublinhando dinâmicas de desruralização e de construção de tecidos urbanos densos onde o anonimato se tornou possível na vivência de experiências, outrora reconduzidas ao silêncio do sujeito socialmente isolado. A diferença, enquanto experiência vivida, tornou-se comunitariamente possível, surgindo grupos que delimitam geograficamente determinadas áreas urbanas a que correspondem afinidades eróticas ou de práticas sexuais, inicialmente de gays e lésbicas. Quebra-se na prática a uni-direccionalidade entre sexo e género, entre sexo e sexualidade, questionando-se esquemas de relações assimétricas e modelos de pensamento enraizados (heterossexualidade, patriarcado, machismo, etc.). Rubin (1975 in Lewin 2006, in Vance, 1984) propõe a existência de dois sistemas diferenciados de sexo e género que tornam plausível, sob o ponto de vista analítico, a não correspondência entre sexo, género e sexualidade. O paradigma máximo desta autonomia sistémica alcança-se na construção de uma identidade travesti. Esta identidade mutante, mutável e instável parece acompanhar um mundo de fluxos intensos e interdependências múltiplas. É na sociedade global que as travestis encontram espaço para a vivência comunitária da sua experiência, constituindo-se como um grupo com práticas transnacionais, marcado pela mobilidade de género e geográfica, primeiramente dentro das fronteiras brasileiras e depois para a Europa. Cidade, prostituição e migração surgem como factores chave da disseminação geográfica e identitária desta comunidade. Este projecto tomado sob uma perspectiva global mantêm ou reinventa relações com a estrutura, que aparentemente as apaga enquanto actores sociais e da qual, aparentemente, se auto-excluem.
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This work presents a numerical study of the 4:1 planar contraction flow of a viscoelastic fluid described by the simplified Phan-Thien–Tanner model under the influence of slip boundary conditions at the channel walls. The linear Navier slip law was considered with the dimensionless slip coefficient varying in the range ½0; 4500. The simulations were carried out for a small constant Reynolds number of 0.04 and Deborah numbers (De) varying between 0 and 5. Convergence could not be achieved for higher values of the Deborah number, especially for large values of the slip coefficient, due to the large stress gradients near the singularity of the reentrant corner. Increasing the slip coefficient leads to the formation of two vortices, a corner and a lip vortex. The lip vortex grows with increasing slip until it absorbs the corner vortex, creating a single large vortex that continues to increase in size and intensity. In the range De = 3–5 no lip vortex was formed. The flow is characterized in detail for De ¼ 1 as function of the slip coefficient, while for the remaining De only the main features are shown for specific values of the slip coefficient.
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[Excerpt] A large number of constitutive equations were developed for viscoelastic fluids, some empirical and other with strong physical foundations. The currently available macroscopic constitutive equations can be divided in two main types: differential and integral. Some of the constitutive equations, e.g. Maxwell are available both in differential and integral types. However, relevant in tegral models, like K - BKZ, just possesses the integral form. (...)
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OBJECTIVE: Brazil is the country with the largest community of Japanese descendants in the world, from a migration movement that started in 1908. However, more recently (1988), a movement in the opposite direction began. Many of these descendants went to Japan for work purposes and suffered mental distress. Some of them sought treatment in Japan, while others returned to Brazil to seek treatment. The aim of the present study was to compare the sociodemographic profile and diagnoses of Japanese Brazilian psychiatric outpatients in Japan (remaining group) and in Brazil (returning group). METHOD: All consecutive Japanese Brazilian outpatients who received care from the psychiatric units in Japan and Brazil from April 1997 to April 2000 were compared. The diagnoses were based on ICD-10 and were made by psychiatrists. Sociodemographic data and diagnoses in Brazil and Japan were compared by means of the Chi-Squared Test. RESULTS: The individuals who returned to Brazil were mostly male and unmarried, had lived alone in Japan, had stayed there for short periods and were classified in the schizophrenia group. The individuals who remained in Japan were mostly female and married, were living with family or friends, had stayed there for long periods and were classified in the anxiety group. Logistic regression showed that the most significant factors associated with the returning group were that they had lived alone and stayed for short periods (OR = 0.93 and 40.21, respectively). CONCLUSION: We conclude that living with a family and having a network of friends is very important for mental health in the context evaluated.
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In this paper we consider the approximate computation of isospectral flows based on finite integration methods( FIM) with radial basis functions( RBF) interpolation,a new algorithm is developed. Our method ensures the symmetry of the solutions. Numerical experiments demonstrate that the solutions have higher accuracy by our algorithm than by the second order Runge- Kutta( RK2) method.