WorldWideScience

Sample records for internal migration flows

  1. Quantifying global international migration flows.

    Science.gov (United States)

    Abel, Guy J; Sander, Nikola

    2014-03-28

    Widely available data on the number of people living outside of their country of birth do not adequately capture contemporary intensities and patterns of global migration flows. We present data on bilateral flows between 196 countries from 1990 through 2010 that provide a comprehensive view of international migration flows. Our data suggest a stable intensity of global 5-year migration flows at ~0.6% of world population since 1995. In addition, the results aid the interpretation of trends and patterns of migration flows to and from individual countries by placing them in a regional or global context. We estimate the largest movements to occur between South and West Asia, from Latin to North America, and within Africa.

  2. Multiregional estimation of gross internal migration flows.

    Science.gov (United States)

    Foot, D K; Milne, W J

    1989-01-01

    "A multiregional model of gross internal migration flows is presented in this article. The interdependence of economic factors across all regions is recognized by imposing a non-stochastic adding-up constraint that requires total inmigration to equal total outmigration in each time period. An iterated system estimation technique is used to obtain asymptotically consistent and efficient parameter estimates. The model is estimated for gross migration flows among the Canadian provinces over the period 1962-86 and then is used to examine the likelihood of a wash-out effect in net migration models. The results indicate that previous approaches that use net migration equations may not always be empirically justified."

  3. National and international graduate migration flows.

    Science.gov (United States)

    Mosca, Irene; Wright, Robert E

    2010-01-01

    This article examines the nature of national and international graduate migration flows in the UK. Migration equations are estimated with microdata from a matched dataset of Students and Destinations of Leavers from Higher Education, information collected by the Higher Education Statistical Agency. The probability of migrating is related to a set of observable characteristics using multinomial logit regression. The analysis suggests that migration is a selective process with graduates with certain characteristics having considerably higher probabilities of migrating, both to other regions of the UK and abroad.

  4. International migration flows. Framework for understanding and current features.

    Directory of Open Access Journals (Sweden)

    Colectivo IOÉ

    2016-10-01

    Full Text Available The present article aims to outline a framework for the understanding of the present international migratory flows as well as to outline their main traits. In order to do this, we first group together the different migratory flows produced since the sixteenth century up to the mid seventies in the twentieth  century, stopping then for a closer look at the present situation which register the impact of economic globalization, translating it into an increase of said flows and, above all, to their enormous diversification. To end, we make a brief balance of the present period and a critical evaluation on the meaning of one of the flows which attracts most attention, economic migrations south-north, because these are the ones which have the most impact on developed countries.

  5. From places to flows. International secondary migration and birth outcomes.

    Science.gov (United States)

    Urquia, Marcelo L; Frank, John W; Glazier, Richard H

    2010-11-01

    Research on the health status of international migrants to industrialised countries in general, and on perinatal outcomes in particular, has assumed an interpretative model based on primary migration, characterised by one permanent cross-border movement from the migrant's country of birth. However, many migrants experience more complex migration patterns that may also be associated with human health. Secondary migration, defined as a migration from a country of residence other than the country where the immigrant was born, has been growing during the last two decades, favoured by globalisation. The purpose of this study was to examine the association between secondary migration and preterm birth (PTB) and infant birthweight at term (BW) using a Canadian official immigration database to build a cohort of immigrants to Ontario, Canada, who obtained their permanent residence in the years 1985-2000. The study population comprised 320,398 singleton live infants born to immigrant women during 1988-2007. Primary and secondary migrants were categorised according to whether they were born in an industrialised country or not. Secondary migrants were further subdivided according to whether the country from which they migrated to Canada was industrialised or not. We found that compared to primary migrants, secondary migrants to Canada born in non-industrialised countries had lower odds of PTB and higher mean BW at term. However, such a protective effect was not observed among secondary migrants born in industrialised countries. In a cross-classified multilevel model restricted to secondary migrants, 5.2% of the variation in birthweight was explained by migrants' countries of birth and 0.8% by migrants' countries of last permanent residence. These findings are consistent with the so-called healthy migrant effect, implying that selective migration from non-industrialised countries is associated with protective individual characteristics.

  6. [Internal migration].

    Science.gov (United States)

    Borisovna, L

    1991-06-01

    Very few studies have been conducted that truly permit explanation of internal migration and it repercussions on social and economic structure. It is clear however that a profound knowledge of the determinants and consequences of internal migration will be required as a basis for economic policy decisions that advance the goal of improving the level of living of the population. the basic supposition of most studies of the relationship of population and development is that socioeconomic development conditions demographic dynamics. The process of development in Mexico, which can be characterized by great heterogeneity, consequently produces great regional disparities. At the national level various studies have estimated the volume of internal migration in Mexico, but they have usually been limited to interstate migration because the main source of data, the census, is classified by states. But given the great heterogeneity within states in all the elements related to internal migration, it is clear that studies of internal migration within states are also needed. Such studies are almost nonexistent because of their technical difficulty. National level studies show that interstate migration increased significantly between 1940-80. The proportion of Mexicans living outside their states of birth increased by 558% in those years, compared to the 342% increase in the total Mexican population. Although Puebla has a high rate of increase, migration has kept it below Mexico's national growth rate. Migration between Puebla and other states and within Puebla has led to an increasing unevenness of spatial distribution. Between 1970-80, 57 of Puebla's municipios had growth rates above the state average of 2.8%/year, 6 had growth rates equal to the average, and 129 had growth rates that were below the average but not negative. 25 states with negative growth rates that were considered strongly expulsive. In 1980, 51.7% of the population was concentrated in the 57 municipios

  7. Linked migration systems: immigration and internal labor flows in the United States.

    Science.gov (United States)

    R. Walker; M. Ellis; R. Barff

    1992-01-01

    We investigate the relationship between immigration and internal labor movements in the US. Wedding the literatures on immigration and internal migration, we develop a mobility model linking these various flows on the basis of occupational status of worker, producction and institutional relations in the economy, and economic restructuring.

  8. Overcoming the Problems of Inconsistent International Migration data: A New Method Applied to Flows in Europe.

    Science.gov (United States)

    de Beer, Joop; Raymer, James; van der Erf, Rob; van Wissen, Leo

    2010-11-01

    Due to differences in definitions and measurement methods, cross-country comparisons of international migration patterns are difficult and confusing. Emigration numbers reported by sending countries tend to differ from the corresponding immigration numbers reported by receiving countries. In this paper, a methodology is presented to achieve harmonised estimates of migration flows benchmarked to a specific definition of duration. This methodology accounts for both differences in definitions and the effects of measurement error due to, for example, under reporting and sampling fluctuations. More specifically, the differences between the two sets of reported data are overcome by estimating a set of adjustment factors for each country's immigration and emigration data. The adjusted data take into account any special cases where the origin-destination patterns do not match the overall patterns. The new method for harmonising migration flows that we present is based on earlier efforts by Poulain (European Journal of Population, 9(4): 353-381 1993, Working Paper 12, joint ECE-Eurostat Work Session on Migration Statistics, Geneva, Switzerland 1999) and is illustrated for movements between 19 European countries from 2002 to 2007. The results represent a reliable and consistent set of international migration flows that can be used for understanding recent changes in migration patterns, as inputs into population projections and for developing evidence-based migration policies.

  9. Monitoring international migration flows in Europe. Towards a statistical data base combining data from different sources

    OpenAIRE

    Willekens, F.J.

    1994-01-01

    The paper reviews techniques that have been developed in demography, geography and statistics, and that are useful for bridging the gap between available data on international migration flows and the information required for policy making and research. The basic idea of the paper is that, in order to establish a coherent and consistent data base that contains sufficiently detailed, up-to-date and accurate information, data from several sources should be combined. That raises issues of definit...

  10. Estimates of internal migration flows for the UK, 2000-2007.

    Science.gov (United States)

    Dennett, Adam; Rees, Phil

    2010-01-01

    Statistics on migration flows year by year within the UK are produced by the Office for National Statistics, the General Register Office for Scotland and the Northern Ireland Statistics Research Agency for migration within England and Wales, within Scotland and within Northern Ireland respectively. However, these flow statistics are not integrated across the UK. As there was a need for such integrated flow statistics at a sub-national scale known as NUTS2 for an EU sponsored project, the authors developed a synthetic estimate of migration flows for the calendar years 2000 to 2007 and the mid-year to midyear intervals 1999-2000 to 2006-07. The estimates were controlled by the migration flows published at NUTS1 scale from the UK wide NHS Central Register to which country specific flows between NUTS2 regions from the various patient registers were fitted. The gaps, flows between regions in different devolved territories, were filled by adjusting comprehensive flow data from the 2001 Census to the published NHSCR flows. Age detail was added only to the total out-migration and in-migration flows from each region using a fixed national profile of migration rates by age from the 2001 Census. The resulting time series of flow data provide, therefore, the three matrix faces of an origin-destination-age array for each time period. The paper describes the details of the estimation process and reports on some of the trends that the time series show.

  11. Exploring Links between Internal and International Migration in Albania : a View from Internal Migrants

    NARCIS (Netherlands)

    Caro, Erka; Bailey, Ajay; Van Wissen, Leo J. G.

    Over the last 20years, Albania has experienced sweeping economic and social changes, caused in part by increasing internal and international migration flows. Migration trajectories of Albanians represent a combination of internal, international, and return migration. Whereas scholars have previously

  12. Overcoming the problems of inconsistent international migration data: a new method applied to flows in Europe

    NARCIS (Netherlands)

    de Beer, J.A.A.; Raymer, J.; van der Erf, R.F.; van Wissen, L.J.G.

    2010-01-01

    Due to differences in definitions and measurement methods, crosscountry comparisons of international migration patterns are difficult and confusing. Emigration numbers reported by sending countries tend to differ from the corresponding immigration numbers reported by receiving countries. In this pap

  13. A theory of international migration flows: United States immigration from Mexico.

    Science.gov (United States)

    Graves, P E; Knapp, T A

    1984-01-01

    The relevance of concepts of equilibrium to the analysis of migration between Mexico and the United States is examined. A theoretical model applicable to this type of international migration is first developed. The next section "presents some limited and tentative empirical observations and suggests the knowledge which might be needed for a more precise understanding of the utility differentials between countries which give rise to migration, legal or illegal." A final section is devoted to the policy implications of this approach to migration analysis.

  14. International migration in Serbia: Facts and policies

    OpenAIRE

    Bobić Mirjana; Babović Marija

    2013-01-01

    In the absence of comprehensive, systematic and precize data on international migration in Serbia, and consequently the analysis of migration trends, their drivers and outcomes, the objective of this paper is to offer the review of contemporary migration flows in Serbia. International migration flows are observed in the context of semi-peripheral position of Serbia in the global system, and hindered transformation and development. Migrations are analyzed at the macro level, according to...

  15. MONITORING INTERNATIONAL MIGRATION FLOWS IN EUROPE - TOWARDS A STATISTICAL-DATA BASE COMBINING DATA FROM DIFFERENT SOURCES

    NARCIS (Netherlands)

    WILLEKENS, F

    1994-01-01

    The paper reviews techniques developed in demography, geography and statistics that are useful for bridging the gap between available data on international migration flows and the information required for policy making and research. The basic idea of the paper is as follows: to establish a coherent

  16. MONITORING INTERNATIONAL MIGRATION FLOWS IN EUROPE - TOWARDS A STATISTICAL-DATA BASE COMBINING DATA FROM DIFFERENT SOURCES

    NARCIS (Netherlands)

    WILLEKENS, F

    1994-01-01

    The paper reviews techniques developed in demography, geography and statistics that are useful for bridging the gap between available data on international migration flows and the information required for policy making and research. The basic idea of the paper is as follows: to establish a coherent

  17. Challenges for Schools in Communities with Internal Migration Flows: Evidence from Turkey

    Science.gov (United States)

    Akar, Hanife

    2010-01-01

    Turkey is a country that has experienced and continues to experience a dramatic degree of both rural-to-urban and inter-regional internal migration. Migrants tend to settle in "gecekondu" areas in either established inner-city neighborhoods or in newer squatter settlements built on undeveloped land bordering rural areas on the urban…

  18. Overcoming the Problems of Inconsistent International Migration data : A New Method Applied to Flows in Europe

    NARCIS (Netherlands)

    de Beer, Joop; Raymer, James; van der Erf, Rob; van Wissen, Leo

    2010-01-01

    Due to differences in definitions and measurement methods, cross-country comparisons of international migration patterns are difficult and confusing. Emigration numbers reported by sending countries tend to differ from the corresponding immigration numbers reported by receiving countries. In this pa

  19. International Migration of Couples

    DEFF Research Database (Denmark)

    Junge, Martin; Munk, Martin D.; Poutvaara, Panu

    2017-01-01

    Migrant self-selection is important to both origin and destination countries. We develop a theoretical model regarding the migration of dual-earner couples and test it in the context of international migration, using population-wide administrative data from Denmark. Our model predicts...

  20. Population commission discusses international migration.

    Science.gov (United States)

    1997-01-01

    At the 30th session of the Commission on Population and Development during February 24-28, 1997, international migration was the main topic, with special linkages between migration and development and on gender issues and the family. New and emerging issues were also considered. Members stressed the need for more reliable data on migration, the direction of migrants flows, and the characteristics of migrants. The Commission requested a task force on basic social services to hold a technical symposium of experts on international migration in 1998. Its chair, Dr. Nafis Sadik, said that migration issues should based on the reality of choice not on coercive measures or quotas. Almost half of the migrants globally are women. The Commission was given a new impetus by the International Conference on Population and Development held at Cairo in 1994. Migration pressures intensified in the second half of the 1980s and in the early 1990s, creating areas of concern: the negative impact of short-term migration on working conditions in host countries; migration pressures emanating from climatic change; the protection of migrant women and their children; the right of receiving countries to regulate access to their territory; the adverse consequences of forced migration; the situation of persons whose asylum claims have been rejected; the trafficking in women and children, prostitution and coercive adoption; and the sudden and massive arrival of refugees in need of international protection. The 1998 session of the Commission will feature the theme of health and mortality, with special emphasis on the linkages between health and development and on gender and age.

  1. International migration: a global challenge.

    Science.gov (United States)

    Martin, P; Widgren, J

    1996-04-01

    Trends in international migration are presented in this multiregional analysis. Seven of the world's wealthiest countries have about 33% of the world's migrant population, but under 16% of the total world population. Population growth in these countries is substantially affected by the migrant population. The migration challenge is external and internal. The external challenge is to balance the need for foreign labor and the commitment to human rights for those migrants seeking economic opportunity and political freedom. The internal challenge is to assure the social adjustment of immigrants and their children and to integrate them into society as citizens and future leaders. Why people cross national borders and how migration flows are likely to evolve over the next decades are explained. This report also presents some ways that countries can manage migration or reduce the pressures which force people to migrate. It is recommended that receiving nations control immigration by accelerating global economic growth and reducing wars and human rights violations. This report examines the impact of immigration on international trade, aid, and direct intervention policies. Although migration is one of the most important international economic issues, it is not coordinated by an international group. The European experience indicates that it is not easy to secure international cooperation on issues that affect national sovereignty. It is suggested that countries desiring control of their borders should remember that most people never cross national borders to live or work in another country, that 50% of the world's migrants move among developing countries, and that countries can shift from being emigration to immigration countries. The author suggests that sustained reductions in migration pressure are a better alternative than the "quick fixes" that may invite the very much feared mass and unpredictable movements.

  2. Biometrics and international migration.

    Science.gov (United States)

    Redpath, Jillyanne

    2007-01-01

    This paper will focus on the impact of the rapid expansion in the use of biometric systems in migration management on the rights of individuals; it seeks to highlight legal issues for consideration in implementing such systems, taking as the starting point that the security interests of the state and the rights of the individual are not, and should not be, mutually exclusive. The first part of this paper briefly describes the type of biometric applications available, how biometric systems function, and those used in migration management. The second part examines the potential offered by biometrics for greater security in migration management, and focuses on developments in the use of biometrics as a result of September 11. The third part discusses the impact of the use of biometrics in the management of migration on the individual's right to privacy and ability to move freely and lawfully. The paper highlights the increasing need for domestic and international frameworks to govern the use of biometric applications in the migration/security context, and proposes a number of issues that such frameworks could address.

  3. ILO - International Migration Programme.

    Science.gov (United States)

    Boudraa, Miriam

    2011-01-01

    In a wide International Context characterised not only by the economical development but also by the social, cultural, political and individual development, we witness more and more to a exchange between the developed and the developing countries, which can be translated especially in the migration of the work force. In theory, all countries are either countries of origin either countries of transit or destination, and they are all responsible for the rights of migrant workers by promoting the rights, by monitoring and by preventing the abusive conditions. The process of migration of the workforce can be divided into three stages: the first coincides with the period prior to departure, the second is represented by the aftermath of the departure and the period of stay in the country of destination, the third stage corresponds to the return in the country of origin. The workers must be protected throughout this process by the international organizations that perform the catalytic role of communication and exchange between countries, for the only purpose of protecting the rights of immigrant and/or immigrants workers. The responsibility for the protection of workers is divided among the various players in the International Labour Organisation. Every country has to apply measures according to the international standards regarding workers' rights, standards that guide the various countries in the formulation and implementation of their policies and legislation. These standards are suggested by International Conventions, the ILO Conventions and other international instruments such as the human rights instrument. There has been a big step forward once the ILO Fundamental Conventions and Conventions on Migrant Workers where implemented and this implementation represented the use of the Guidelines "ILO Multilateral Framework on Labour Migration".

  4. INTERNATIONAL MIGRATION, GLOBALIZATION AND DEMOGRAPHIC DEVELOPMENT OF THE RUSSIAN FEDERATION

    OpenAIRE

    Aleshkovski, Ivan

    2012-01-01

    In the article, the author analyzes the impact of globalization on the transformation of international migration flows in the Russian Federation. The author considers the features of global trends in international migration in Russia: increasing involvement of Russia and its regions in the international migration, the qualitative changes in the structure of migration flows, the increasing role of international migration as a factor of the country's demographic development.

  5. Internal migration transition in Romania?

    OpenAIRE

    Horváth, István

    2016-01-01

    This paper is an overview of the shifts in the internal migration patterns in Romania for the last six decades. In the first part a literature-based brief overview of the trends and patterns of internal migration during communism will be presented. In the second (more extensive) part, a statistical-data based analysis of the internal migration trends and patterns over the last 25 years will be provided.

  6. International migration statistics in Mexico.

    Science.gov (United States)

    Garcia Y Griego, M

    1987-01-01

    During the past decade, Mexico has experienced both large-scale emigration directly, mostly to the US, and the mass immigration of Central American refugees. The implementation of the US Immigration and Control Act of 1986 and the possible escalation of armed conflicts in Central America may result in expanded inflows either of returning citizens or of new refugee waves. To develop appropriate policy responses, Mexico needs reliable information on international migration flows. This research note reviews available sources of that information--arrival and departure statistics, population censuses, refugee censuses, and survey data--and concludes that most of them are relatively weak. Currently, the published data on entries and departures provide little information on the demographic impact of legal migration, although they suggest that the inflow of foreigners is small. The census corroborates such findings, but it yields inadequate demographic detail. The movement of Mexican nationals, on the other hand, is poorly reflected by both sources. The void they leave has been palliated somewhat by surveys, but the only nationally representative survey on emigration was carried out in the late 1970s and might be a less than ideal basis for current policy formulation. It is hoped that as the relevance of international migration becomes more evident, steps towards the improvement of existing statistical systems may be undertaken. In the absence of such measures, policy-makers and researchers will have to continue relying on ad hoc surveys to answer the most pressing questions on the subject.

  7. Incentives and disincentives: international migration.

    Science.gov (United States)

    Bhagwati, J N

    1984-01-01

    International migration is largely controlled by disincentives, or quotas, on immigration rather than checks on emigrations. Societies generally feel they have a right to exclude others from their boundaries, but they also usually feel that they do not have a right to control emigration. The single-planetary approach holds that people have the right to live wherever they like on the planet, and the cosmopolitan-utilitarian approach believes the same for reasons of world efficiency. The current feeling that societies have the right to exclude others may be explained best by territoriality in human animals. People also believe that their culture will be diluted if too many outsiders enter. In many cases, immigration systems cannot really control immigration, as in the cases of long landlocked borders between the US and Mexico and between Bangladesh and Assam. Immigration systems also contain legal loopholes. For example, in the US it is easier to get a student visa and convert to immigrant status than to gain immigrant status directly. Loopholes lead to plugs, which lead in turn to more loopholes. An upsurge in requests for political asylum followed increased restrictions on immigration in Western Europe. The US has investigated foreign aid and foreign investments to Mexico and Haiti to curb the flow of illegal migrants. The author suggests that foreign investments may lead to more migration because of the creation of a new proletariat used to the ways of developed countries. An estimate of what would happen if all immigration control were removed worldwide concludes that efficiency and income distribution would improve worldwide. Most migration from developing to developed countries currently consists of the migration of skilled professionals, the brain drain. The author proposes a tax on these professionals to be paid to the country of origin to compensate them for the loss in education and training. The author summarizes the differences between the West German

  8. Globalization of international migration: Social challenges and policy implication

    Directory of Open Access Journals (Sweden)

    I A Aleshkovski

    2017-12-01

    Full Text Available In the second half of the XX century, the humankind witnessed the insurmountable and irreversible power of globalization processes, which influence all spheres of social life and establish a global system of interdependency between countries and nations. Globalization within impetuous changes in global political, social and economic systems has determined dramatic shifts in the international migration processes that lead to the new stage of migration history. In nowadays globalized world, international migration has become a reality for almost all corners of the globe. The author considers features of the recent trends of international migration: the unprecedented growth of the international migration flows; the widening geography of international migration that involves nearly all countries of the world; qualitative changes in the structure of international migration flows; the key role of economic migration; the permanent growth and structural intricateness of irregular migration; the increasing scale and geographical widening of forced migration; the growing importance of international migration for the demographic development of the world, countries of both origin and destination. All these trends combined prove that the international migration patterns have become more complex. The author analyzes the legal framework of the international migration processes, and gives recommendations on the ways to improve the control and regulation of migration processes. Specific issues related to the social challenges of international migration are also discussed in the article.

  9. Towards an integrated model of international migration

    Directory of Open Access Journals (Sweden)

    Douglas S. MASSEY

    2012-12-01

    Full Text Available Demographers have yet to develop a suitable integrated model of international migration and consequently have been very poor at forecasting immigration. This paper outlines the basic elements of an integrated model and surveys recent history to suggest the key challenges to model construction. A comprehensive theory must explain the structural forces that create a supply of people prone to migrate internationally, the structural origins of labour demand in receiving countries, the motivations of those who respond to these forces by choosing to migrate internationally, the growth and structure of transnational networks that arise to support international movement, the behaviour states in response to immigrant flows, and the influence of state actions on the behaviour of migrants. Recent history suggests that a good model needs to respect the salience of markets, recognize the circularity of migrant flows, appreciate the power of feedback effects, and be alert unanticipated consequences of policy actions.

  10. International Migration of Couples

    DEFF Research Database (Denmark)

    Junge, Martin; Munk, Martin D.; Nikolka, Till

    2017-01-01

    Migrant self-selection is important to labor markets and public finances in both origin and destination countries. We develop a theoretical model regarding the migration of dual-earner couples and test it using population-wide administrative data from Denmark. Our model predicts that the probabil......Migrant self-selection is important to labor markets and public finances in both origin and destination countries. We develop a theoretical model regarding the migration of dual-earner couples and test it using population-wide administrative data from Denmark. Our model predicts...

  11. Interregional migration flows in Indonesia

    NARCIS (Netherlands)

    Wajdi, N.; van Wissen, L.J.G.; Mulder, C.H.

    2015-01-01

    Population Census and Intercensal Population Survey data permit description of the origin–destination patterns that characterize interregional migration flows in Indonesia. Application of the framework of population redistribution proposed by Long (1985) results in indications of over-urbanization,

  12. Reinventing US Internal Migration Studies in the Age of International Migration.

    Science.gov (United States)

    Ellis, Mark

    2012-03-01

    I argue that researchers have sidelined attention to issues raised by US internal migration as they shifted focus to the questions posed by the post-1960s rise in US immigration. In this paper, I offer some reasons about why immigration has garnered more attention and why there needs to be greater consideration of US internal migration and its significant and myriad social, economic, political, and cultural impacts. I offer three ideas for motivating more research into US internal geographic mobility that would foreground its empirical and conceptual connections to international migration. First, there should be more work on linked migration systems investigating the connections between internal and international flows. Second, the questions asked about immigrant social, cultural, and economic impacts and adaptations in host societies should also be asked about internal migrants. Third, and more generally, migration researchers should jettison the assumption that the national scale is the pre-eminent delimiter of migration types and processes. Some groups can move easily across borders; others are constrained in their moves within countries. These subnational scales and constraints will become more visible if migration research decentres the national from its theory and empirics.

  13. Forecasting of Interregional Migration Flows

    Directory of Open Access Journals (Sweden)

    Yuriy Davydovich Shmidt

    2017-03-01

    Full Text Available The article explores the problem of interregional migration flows modelling. As a rule, the existing models of interregional migration flows use the aggregated data and do not take into consideration the fact that a decision to relocate is formed and taken at the micro-level, at the level of households. The purpose of the present research is to develop the forecasting method for interregional migration flows of the region taking into consideration the behaviour of households at the micro-level. The research tests the hypothesis that the modelling of household behaviours at the local level as regards taking a decision to relocate to other regions, which takes into account the existing interactions with relatives and other communities, allows to obtain adequate forecasts of interregional migration flows. To forecast the interregional migration flows of the region, we develop a methodological approach and software solution, based on cellular automaton model modification proposed in the current work and on econometric models of birth and death processes, which have been tested on the Primorsky Krai data. The authors’ model of the cellular automaton is a kind of the combined probabilistic cellular automaton in which the condition of each cell changes depending on a condition of four closest neighbours (von Neumann vicinity and four cells chosen in a random way. The article builds a mid-term forecast of Primorsky Krai interregional migration flows. The research demonstrates the possibility and reasonability of modelling the interregional migration flows by cellular automatons. The highly perspective direction of the research is the modelling of other macroeconomic processes based on modelling by cellular automatons of a behaviour of households, companies and other economic entities at the local level.

  14. The International-Migration Network

    CERN Document Server

    Fagiolo, Giorgio

    2012-01-01

    This paper studies international migration from a complex-network perspective. We define the international-migration network (IMN) as the weighted-directed graph where nodes are world countries and links account for the stock of migrants originated in a given country and living in another country at a given point in time. We characterize the binary and weighted architecture of the network and its evolution over time in the period 1960-2000. We find that the IMN is organized around a modular structure characterized by a small-world pattern displaying disassortativity and high clustering, with power-law distributed weighted-network statistics. We also show that a parsimonious gravity model of migration can account for most of observed IMN topological structure. Overall, our results suggest that socio-economic, geographical and political factors are more important than local-network properties in shaping the structure of the IMN.

  15. International migration, international relations and foreign policy.

    Science.gov (United States)

    Mitchell, C

    1989-01-01

    Recent literature on migration, international relations, and foreign policy is reviewed in this article, stressing applications of global systems paradigms, studies of state entry and exit rules, and anatomies of domestic policy-setting processes on migration. After a concise assessment of the contemporary theory of global political economy, the paper argues for seeking mid-range generalizations on the international relations of migration. It also suggests that analysis begin with the policy-setting processes of the state. Especially through the use of comparative perspectives available from domestic policy making studies and from the field of international comparative public policy, this approach offers the opportunity to fix empirically the political roles of transnational social forces, which often present themselves as participants in domestic policy contests. Promising future directions in the study of state-to-state relations are also evaluated, with the anticipation that verifying regional or other intermediate patterns of world migration politics may contribute to more general theories of international political economy.

  16. The role of language in international migration

    DEFF Research Database (Denmark)

    Adsera, Alicia; Pytlikova, Mariola

    Fluency in (or ease to quickly learn) the language of the destination country plays a key role in the transfer of human capital from the source country to another country and boosts the immigrant’s rate of success at the destination’s labor market. This suggests that the ability to learn and speak...... a foreign language might be an important factor in the migration decision. We use a novel dataset on immigration flows and stocks of foreigners in 30 OECD destination countries from 223 source countries for the years 1980–2009 and a wide range of linguistic indicators to study the role of language...... in shaping international migration. Specifically, we investigate how both linguistic distance and linguistic diversity, as a proxy for the “potential” ease to learn a new language and to adapt to a new context, affect migration. We find that migration rates increase with linguistic proximity and the result...

  17. World Migration Degree Global migration flows in directed networks

    CERN Document Server

    Porat, Idan

    2015-01-01

    In this article we analyze the global flow of migrants from 206 source countries to 145 destination countries (2006-2010) and focus on the differences in the migration network pattern between destination and source counters as represented by its degree and weight distribution. Degree represents the connectivity of a country to the global migration network, and plays an important role in defining migration processes and characteristics. Global analysis of migration degree distribution offers a strong potential contribution to understanding of migration as a global phenomenon. In regard to immigration, we found that it is possible to classify destination countries into three classes: global migration hubs with high connectivity and high migration rate; local migration hubs with low connectivity and high migration rate; and local migration hubs with opposite strategy of high connectivity and low migration rate. The different migration strategies of destination countries are emerging from similar and homogenies p...

  18. International Migration ‒ Economic Implications

    Directory of Open Access Journals (Sweden)

    Raluca Mariana Grosu

    2017-08-01

    Full Text Available The desire to discover, to explore new horizons has always been an important characteristic of the human being. Ever since ancient times, people have sought different economic and social opportunities beyond the borders of their territories of origin, mainly driven by the desire for a better living, taking into account various aspects such as work, education, political rights, personal safety, or healthcare. An extremely dynamic, complex and multidimensional phenomenon, migration is an integral part of human development. As a particular case, international migration is a reality that will continue to exist as long as there are discrepancies in terms of wealth and development between different regions of the world, as there are economic, political or social issues. As it allows people to realize their aspirations and it represents an important factor of human and economic exchanges, this phenomenon may represent a great opportunity for development.

  19. International relations and transnational migration: the case of China

    Directory of Open Access Journals (Sweden)

    Xiang Biao

    2005-01-01

    Full Text Available By examining how China became part of the modern world system historically and how it perceives migration in relation to its diplomacy strategy, this paper seeks to shed light on the relationship between transantional migration (supposedly not directly subject to national regulations and international relations (still based on the national sovereignty. The paper suggests that the current international regime can no longer direct transnationalmigration flows, but remains critical in affecting migration in its patterns and its implications for social and economic development. China evidently does not want migration to complicate its international relations, and migrant receiving countries shouldbe cautious in using leverage of international relations when seeking China���s cooperation for migration. The interplay between international relations and transnational migration deserves more research.

  20. Migration Flows in Europe: Space and Time Transformation

    Directory of Open Access Journals (Sweden)

    Zhitin Dmitry

    2016-06-01

    Full Text Available One of the key manifestations of globalisation is an increase in the spatial mobility of population involving growing numbers of people into international migration processes. This article is an attempt to assess the density of migration connections between European states based on the 1990—2015 quantitative data. An analysis of migration flows and relevant net migration and net migration and migration localisation at the national and regional levels makes it possible to identify key trends in the spatial and temporal transformation of this phenomenon on the European continent. Calculations suggest that an increase in migration has not narrowed the gap between source and recipient countries but, on the contrary, it has made it more pronounced over the recent decades. The article presents an attempt at classifying European countries by the direction and intensity of migration connections and stresses the impact of international migration on the demographic and sociocultural situation in different European states.

  1. Les questions de migrations internationales (Questions of International Migrations).

    Science.gov (United States)

    Samman, Mouna Liliane

    1993-01-01

    Education about international migration should (1) utilize a framework of historical evolution; (2) stress the growing interdependence of nations; (3) emphasize universal moral values and the role of the individual in human rights; and (4) consider the complementary or competing portraits of international migration presented by the media. (DMM)

  2. Diaspora Effects in International Migration : Key Questions and Methodological Issues

    OpenAIRE

    Beine, Michel; Docquier, Frederic; Ozden, Caglar

    2011-01-01

    This paper reviews the existing literature on the impact of migrants networks on the patterns of international migration. It covers the theoretical channels at stake in the global effect of the networks. It identifies the key issues, namely the impact on size, selection and concentration of the migration flows. The paper also reviews the empirical hurdles that the researchers face in asses...

  3. World Migration Degree Global migration flows in directed networks

    OpenAIRE

    2015-01-01

    In this article we analyze the global flow of migrants from 206 source countries to 145 destination countries (2006-2010) and focus on the differences in the migration network pattern between destination and source counters as represented by its degree and weight distribution. Degree represents the connectivity of a country to the global migration network, and plays an important role in defining migration processes and characteristics. Global analysis of migration degree distribution offers a...

  4. [Urban employment and internal migration in Peru].

    Science.gov (United States)

    Cotlear, D

    1984-06-01

    The relationship between internal migration and employment problems in Peru is examined. The author argues that regional differences in income distribution are the primary causes of migration, particularly to urban areas. A model of the migration process is developed and tested using data from official sources, surveys, and the published literature.

  5. Migration of South African health workers: the extent to which financial considerations influence internal flows and external movements.

    Science.gov (United States)

    George, Gavin; Atujuna, Millicent; Gow, Jeff

    2013-08-06

    The loss of human resource capacity has had a severe impact on the health system in South Africa. This study investigates the causes of migration focussing on the role of salaries and benefits. Health professionals from public, private and non-governmental (NGO) health facilities located in selected peri-urban and urban areas in KwaZulu-Natal, South Africa were surveyed about their current positions and attitudes toward migration. The study uses cross-sectional data collected in 2009. A total of 694 health professionals (430 in the public sector, 133 in the NGO sector and 131 in the private sector) were surveyed. An additional 11 health professionals were purposively selected for in-depth interviews. Odds ratios with 95% confidence intervals were calculated to determine whether salaries influenced HWs decisions to migrate. HWs decision to move was not positively associated with lower salaries. It was found, instead, that the consideration to move was determined by other factors including age, levels of stress experienced and the extent to which they were satisfied at their current place of work. The OSD appears to have lowered the risk of HWs migrating due to low salaries. However, the results also indicate that the South African Department of Health needs to improve working conditions for HWs within the public health sector to assist in retention.

  6. International migration under the microscope

    NARCIS (Netherlands)

    Willekens, F.J.; Massey, D.; Raymer, J.; Beauchemin, C.

    2016-01-01

    Although humanitarian crises, such as the ongoing mass exodus from Syria toward Europe, tend to focus global attention on migration, each year millions of people migrate to and from affected countries throughout the world. Progress has been made in understanding drivers of migration, and we have

  7. International relations and transnational migration: the case of China

    OpenAIRE

    2005-01-01

    By examining how China became part of the modern world system historically and how it perceives migration in relation to its diplomacy strategy, this paper seeks to shed light on the relationship between transantional migration (supposedly not directly subject to national regulations) and international relations (still based on the national sovereignty). The paper suggests that the current international regime can no longer direct transnationalmigration flows, but remains critical in affectin...

  8. Cultural values in international migration and remittances

    OpenAIRE

    Inna Čábelková

    2014-01-01

    In this paper we study the effects of cultural determinants on the migration flows across countries and the financial flows back to the country of origin of the migrants in the form of remittances. We present econometric models for migration and remittances and test the relations between migration and remittances on one hand and cultural dimensions on the other hand. We find that collectivist countries produce more migrants per one inhabitant. This finding corresponds to social reason for mig...

  9. International migration. World order or disorder?

    Science.gov (United States)

    Marmora, L

    1998-06-01

    This is a general review of global trends in international migration. Topics covered include the internationalization of the global economy, the new international political order, the globalization of culture, the increase in the migration of the more highly qualified, the growth of bias against foreigners, and the lack of social and political response to migration. Although the author maintains "that in comparative terms, current international movements are considerably less than movements in the early stages of the century and that migratory impacts are overrated", he suggests that there is a need to develop strategies and policies to manage migration better in a humane and ethical manner. (EXCERPT)

  10. International migration: concepts, models and state policies

    Directory of Open Access Journals (Sweden)

    J.A. A. Cebrián

    2016-10-01

    Full Text Available The intensification of international migratory flows in recent years has provoked much thinking as to what might be an appropriate national migratory policy. Following this tendency, in this article we present several considerations relating to the ethical implications of migratory policies. Our point of departure for this discussion consists in the analysis of two concepts, which we believe differ in meaning. We refer to the terms solidarity and citizenship, whose function and meaning in «politically correct» discourse (undefined and undefinable we study in this article. Following this we deal with the different models of the state in the Western world. In this way the understanding of the cultural and political factors of international migration which we analyse in the final section of the article is made easier.

  11. Migration Flows: Measurement, Analysis and Modeling

    NARCIS (Netherlands)

    Willekens, F.J.; White, Michael J.

    2016-01-01

    This chapter is an introduction to the study of migration flows. It starts with a review of major definition and measurement issues. Comparative studies of migration are particularly difficult because different countries define migration differently and measurement methods are not harmonized. Insigh

  12. Migration Flows: Measurement, Analysis and Modeling

    NARCIS (Netherlands)

    Willekens, F.J.; White, Michael J.

    2016-01-01

    This chapter is an introduction to the study of migration flows. It starts with a review of major definition and measurement issues. Comparative studies of migration are particularly difficult because different countries define migration differently and measurement methods are not harmonized.

  13. Migration Flows: Measurement, Analysis and Modeling

    NARCIS (Netherlands)

    Willekens, F.J.; White, Michael J.

    2016-01-01

    This chapter is an introduction to the study of migration flows. It starts with a review of major definition and measurement issues. Comparative studies of migration are particularly difficult because different countries define migration differently and measurement methods are not harmonized. Insigh

  14. Internal and International Migration Across the Urban Hierarchy in Albania.

    Science.gov (United States)

    Lerch, Mathias

    2016-01-01

    The interactions between the processes of urbanization and international migration in less developed and transition countries have important repercussions for socioeconomic development, but are not well understood. Based on the retrospective data from the Albanian Living Standards Measurement Survey 2008, we first assess the geography of migration in terms of the rural-urban continuum, the urban hierarchy and the outside world since 1990. We then investigate the spatio-temporal diffusion of rural-to-urban and international movements using survival models. Results reveal an immediate onset of large-scale rural exodus, despite the post-communist crisis. Internal migrants mainly moved to the capital, bypassing secondary cities, and were predominantly female. Initially, international migrants were primarily men who tended to originate from the main urban agglomerations. The diffusion of opportunities to emigrate down the urban hierarchy and across the sexes then redirected the rural exodus abroad, despite domestic economic development. This evolution in population mobility is related to the gendered patterns and interlinkages of the two flows, as well as to rising inequalities within the urban hierarchy.

  15. Developing a new resource on international nurse migration: the international centre on nurse migration.

    Science.gov (United States)

    Nichols, Barbara; Oulton, Judith

    2005-08-01

    A new collaborative project on nurse migration was recently launched by the International Council of Nurses and the Commission on Graduates of Foreign Nursing Schools. This collaboration, the International Centre on Nurse Migration, guided by the principles of ethical recruitment and equitable treatment of migrating nurses, focuses on promoting, collecting, creating, and disseminating data and information on nurse migration; acting as a resource center; tracking trends and patterns of global health care workforce migration; analyzing policy; generating policy options; advocating for sound policy concerning nurse migration; promoting, undertaking, and disseminating research; providing consultant and expert advice; and offering continuing education about migration.

  16. Labor market conditions of leading countries of international migration movement

    Directory of Open Access Journals (Sweden)

    Дмитро Станіславович Чепеленко

    2015-05-01

    Full Text Available In this work the labor markets of the leaders of international migration are considered, it is found an acyclicity of movement indicators of the labor market and their impact on the economic and demographic situation of countries that are the most influential of the global labor market. It is found that indicators, characterizing the labor market, have acyclic nature depending on the direction of migration flows

  17. Diaspora Effects in International Migration : Key Questions and Methodological Issues

    OpenAIRE

    Beine, Michel; Docquier, Frederic; Ozden, Caglar

    2010-01-01

    This paper reviews the existing literature on the impact of migrants networks on the patterns of international migration. It covers the theoretical channels at stake in the global effect of the networks. It identifies the key issues, namely the impact on size, selection and concentration of the migration flows. The paper also reviews the empirical hurdles that the researchers face in assessing the importance of networks. The key issues concern the choice of micro vs a macro approach, the defi...

  18. High-Level Dialogue on International Migration

    Directory of Open Access Journals (Sweden)

    UNHCR

    2006-08-01

    Full Text Available UNHCR wishes to bring the following observations andrecommendations to the attention of the High-LevelDialogue (HLD on International Migration and Development,to be held in New York, 14-15 September 2006:

  19. [Moroccan international migration: recent trends].

    Science.gov (United States)

    Lazaar, M

    1995-01-01

    Recent trends in emigration from Morocco are analyzed. The author describes the policies developed by the Moroccan government regarding emigration and the changing characteristics of the emigrants, as emigrants are becoming younger and are increasingly female. The author concludes that the increasing demand for migrant labor in Europe will result in increased emigration despite the development of restrictive migration policies.

  20. Migration Flows from the Perspective of Sending and Receiving Countries

    DEFF Research Database (Denmark)

    Pytlikova, Mariola

    -based selectivity effects" in international migration. We test whether immigrants from low-income countries, where the educational level is relatively low, tend to go to countries with higher welfare and lower income inequality and whether immigrants from high-income countries tend to go to countries with a lower......There are two specific phenomena that have had a large influence on the development in international migration during the last decades. First, while labor migration flows were dominating in the past, refugee immigrants and family reunion migrants from less developed non-Western countries have been......, the former communist countries have become a relatively new and large source of immigration. In my PhD thesis I analyze the recent developments in international migration by using a rich dataset, which I collected myself by contacting national statistical offices. I use state-of-art econometric tools in my...

  1. Internal migration in Mexico and its determinants

    Directory of Open Access Journals (Sweden)

    Rogelio Varela Llamas

    2016-12-01

    Full Text Available This paper presents an analysis of internal migration in Mexico. Using micro data from the National Survey on Occupation and Employment (enoe, we estimate a multinomial logit model for the case of intrastate and interstate migration. We also conduct estimations for municipalities of different sizes. The results suggest that the probability of migrating increases with the number of weeks spent searching for a job, regardless of whether the search is conducted while the individual is employed or unemployed. In addition, we find that as the number of hours of work per week increases, the probability of migrating rises. The search process does not increase the probability of migrating in rural communities as it does in urban centers.

  2. Processes of Internal and International Migration from Chitwan, Nepal.

    Science.gov (United States)

    Bohra, Pratikshya; Massey, Douglas S

    2009-01-01

    In this study we examine which factors predict internal and international migration from Chitwan, a flat valley located in the South-Central region of Nepal, seeking to measure the effect of theoretically specified variables such as human capital, social capital, physical capital, and neighborhood socioeconomic conditions while controlling for demographic variables. We use data from the Chitwan Valley Family Study (CVFS) to estimate a series of discrete time event history models of first and repeat migration to three competing destinations: other locations within Chitwan, other districts within Nepal, and places outside of Nepal. Results support hypotheses derived from neoclassical economics, the theory of new economics of migration, social capital theory, and cumulative causation theory. Our results underscore the need for a synthetic theoretical model that incorporates factors operating at the individual, household, and community levels. The use of multiple explanatory models yields a clearer picture of the forces driving internal and international migration from rural districts in developing nations such as Nepal.

  3. Cultural values and international migration

    Directory of Open Access Journals (Sweden)

    Miryam Rodríguez Monter

    2009-05-01

    Full Text Available Immigration is one of the most controversial social issues debated nowadays. It is an undeniable fact that the phenomenon is lived in Europe with concern because of its consequences. People who live and coexist in Europe represent a huge cultural variety. Therefore, social and cultural gaps that can affect the basic values of the western societies seem to be inevitable due to the dimensions of the current migration phenomenon. The present studies are based on the European Social Survey Questionnaire (2002, and the Portrait Values Questionnaire (Schwartz, 1992, 2001 and focuses on the relevance of cultural values to explain the acceptance or rejection of the immigrant.. Finally, we emphasize the importance of cultural values -like Harmony or Egalitarianism- for any initiative or social policy which aimes at reducing the problems concerning inmigration in the European context.

  4. [Internal migration changes from 1980 to 1990].

    Science.gov (United States)

    Corona Vazquez, R

    1991-01-01

    From 1930 to the 1970s, internal migration in Mexico consisted mostly of permanent movement from rural areas to cities, and especially to the 3 metropolitan areas of Mexico City, Monterrey, and Guadalajara. The migrations highlighted the developmental disparities between different regions. Their main consequence was the transformation of Mexico from a predominantly rural to a predominantly urban country. The regions expelling population were primarily densely populated and relatively unproductive areas in the center and south. Migrant destinations were the more developed and urban states. By 1980-90, there were a number of changes in migratory patterns that, along with participation of a greater number of household members in marginal economic activities, represented alternative survival strategies adopted by large population sectors in the face of declining living standards, natural disasters such as the earthquakes of 1985, and increasing ecological and safety problems in the large cities. Changes in migratory behavior during the 1980s included appearance and growing importance of new destinations, and the combination of permanent and temporary migration and of internal and international migration in the same localities, households, or even individuals. Greater distances were covered by migrants in the 1980s, and the relationship between socioeconomic status and migration became more varied. Another change was the decreased importance of migration to the 3 metropolitan areas. Metropolitan Mexico City even became a net expeller of population. At the same time, many medium-sized cities such as Orizaba, Matamoros, Juarez, and Tiajuana have become attractive destinations for migrants from surrounding areas and from Mexico City. The case of Baja California illustrates the combined occurrence of different types of migrations. Baja California in past decades had a high rate in-migration, but its growth has slowed. A greater diversity of origins and destinations is

  5. [International migration in the Americas: intraregional migration grows].

    Science.gov (United States)

    Zlotnik, H

    1992-01-01

    The principal destinations for intraregional migrants in South America in recent decades have been Argentina, Brazil, and Venezuela, while in North America the U.S. has exerted a growing attraction since 1965. Intraregional migration in Latin America has been irregular and difficult to quantify, and reliable statistics on migratory flows are nonexistent. Census data indicate that most migration to Argentina and Brazil occurred before 1960, while most migration to Venezuela occurred during the 1970s. Between 1960 and 1980, the proportion of migrants from other Latin American countries showed a tendency to increase, despite decreases in the overall level of immigration. The effect of the economic crisis of the 1980s on immigration from Latin American countries will become more apparent as census data for the 1990s become available. Selectivity according to country of origin is an important characteristic of intraregional migration in South America. The U.S. has, however, been the principal destination of Latin American migrants for the past three decades. Between 1965 and 1991 the U.S. granted resident status to more than 7.4 million persons of Latin American and Caribbean origin, and they constituted 47% of immigrants during those years. The great majority of the Latin American immigrants in the U.S. are Mexican. The 3.5 million Mexicans admitted to the U.S. as immigrants between 1965 and 1991 accounted for 22% of all immigrants during this period.

  6. International migration links of the Middle Ural

    Directory of Open Access Journals (Sweden)

    Andrey Aleksandrovich Nosov

    2011-03-01

    Full Text Available Based on statistical data, international migration is considered as a complex relations of Sverdlovsk region, a quantitative and qualitative assessment of these relationships is given. Based on the evaluation of statistical data, as well as by studying the analytic literature, the role and place of Sverdlovsk region in the Ural Federal District is substantiated. A country, for which the region is an attractive region of migration, is designated. The dynamics of migration in recent years is disclosed and explained. An attempt to explain the qualitative composition of migrants, namely, migrants from the former Soviet Union and immigration from abroad, is made. Detailed statistics for these countries is provided. Based on the findings on thr dynamics and qualitative composition of people arriving and departing, a forecast of the migration situation in Sverdlovsk region as a key region in the Federal District is made.

  7. International migration network: topology and modeling.

    Science.gov (United States)

    Fagiolo, Giorgio; Mastrorillo, Marina

    2013-07-01

    This paper studies international migration from a complex-network perspective. We define the international migration network (IMN) as the weighted-directed graph where nodes are world countries and links account for the stock of migrants originated in a given country and living in another country at a given point in time. We characterize the binary and weighted architecture of the network and its evolution over time in the period 1960-2000. We find that the IMN is organized around a modular structure with a small-world binary pattern displaying disassortativity and high clustering, with power-law distributed weighted-network statistics. We also show that a parsimonious gravity model of migration can account for most of observed IMN topological structure. Overall, our results suggest that socioeconomic, geographical, and political factors are more important than local-network properties in shaping the structure of the IMN.

  8. Walls Won’t Work : International law for sustainable migration

    NARCIS (Netherlands)

    Brus, Marcel

    2016-01-01

    In this essay I argue that to find sustainable solutions for handling international migration it is necessary to develop fundamental international principles on migration as a basis for global governance and international law. The essay briefly discusses general aspects of migration and migration la

  9. Walls Won’t Work : International law for sustainable migration

    NARCIS (Netherlands)

    Brus, Marcel

    2016-01-01

    In this essay I argue that to find sustainable solutions for handling international migration it is necessary to develop fundamental international principles on migration as a basis for global governance and international law. The essay briefly discusses general aspects of migration and migration la

  10. International Student Migration: Outcomes and Implications

    Science.gov (United States)

    McGill, Jenny

    2013-01-01

    The present study examined the possible correlation between six life circumstances of international students (N = 124) admitted entry into the United States for the purpose of academic study and their geographic choice of location upon graduation. This paper improves upon the current literature by offering actual migration outcomes (rather than…

  11. Internal Migration. UNITAR News, Vol. 8, 1976.

    Science.gov (United States)

    Isaacs, Laurel, Ed.; McDougall, Christina, Ed.

    This UNITAR News Issue presents the background and working papers prepared and utilized by the participants in a workshop on Planning for Internal Migration held in Jamaica and Cuba in April 1976. This workshop, attended by planners and government officials from the Caribbean and some Latin American countries, convened to discuss mutual problems…

  12. The Role of Language in Shaping International Migration

    DEFF Research Database (Denmark)

    Adsera, Alicia; Pytlikova, Mariola

    in shaping international migration. Specifically, we investigate how both linguistic distance and linguistic diversity, as a proxy for the “potential” ease to learn a new language and to adapt to a new context, affect migration. We find that migration rates increase with linguistic proximity and the result......Fluency in (or ease to quickly learn) the language of the destination country plays a key role in the transfer of human capital from the source country to another country and boosts the immigrant’s rate of success at the destination’s labor market. This suggests that the ability to learn and speak...... a foreign language might be an important factor in the migration decision. We use a novel dataset on immigration flows and stocks of foreigners in 30 OECD destination countries from 223 source countries for the years 1980–2009 and a wide range of linguistic indicators to study the role of language...

  13. [The foundation of international migration policies in Latin America].

    Science.gov (United States)

    Marmora, L

    1988-12-01

    A government's international migration policies are intended to influence the size, composition, direction, destination, or integration of international migratory flows. The justification for migratory policies has been based on a series of themes that have had varied weights in different stages of Latin American history. Migrations as population settlement, the desired or undesired characteristics of migrants, the economic impact of migration, the role of migration in relations between countries, and the ethical dimensions of migratory movement have been the major policy issues. The 1st migration policies in Latin America saw international migration as a means of settling the colonies. After independence, migratory policies oriented toward massive settlement became common. Although the stated goals were to settle entire territories with immigrants, the usual result was to absorb immigrants in certain economic sectors with high demand for labor. In the colonial period both Spain and Portugal attempted to restrict immigration to the Catholic segment of their own populations. After independence, the criteria were liberalized somewhat but still reflected prejudices about the racial superiority of certain types of European immigration. The selection principals which appeared most clearly during the 19th century were overwhelmed to the extent that immigration was tranformed into provision of labor to meet unsatisfied needs for workers. Indiscriminate admissions and recourse to nontraditional elements such as Chinese and Japanese was strongest in countries needing labor for tropical agriculture or extractive industries. The economic argument that migration contributed to development was widespread economic argument that migration contributed to development was widespread in the 19th and early 20th centuries, but new rules were made to restrict immigration to protect local labor markets during the worldwide depression of the 1930s. In recent decades, migration policies

  14. Internal migration in India in the seventies: a demo-economic analysis.

    Science.gov (United States)

    Nair, P S

    1986-01-01

    "This paper is aimed to address mainly the following three aspects of spatial mobility within India during the last inter-censal decade of 1971-1981: (i) Levels of inmigration, outmigration and net migration in the major states (ii) estimates of state-to-state migration flows and (iii) some insights on the socio-economic determinants of internal migration."

  15. Towards understanding international migration determinants today: Theoretical perspective

    Directory of Open Access Journals (Sweden)

    Predojević-Despić Jelena

    2010-01-01

    Full Text Available In times of global migration flows and ever increasing mobility of the workforce in the world, the necessity for constant deepening of theoretical knowledge is imposed as a basis for understanding main determinants of this phenomenon, and with an aim of directing the focus of migration researches towards more efficient overcoming of challenges and making use of the advantages which international migrations could bring both to origin, destination and transit countries. The main goal of this paper is to give a critical review on the development of the economic migrations theory, to state the main similarities and differences between various approaches and to point out to the main drawbacks and problems which the theoretical perspective is facing when studying the determinants of contemporary international labor migrations. The focus of the study refers to voluntary labor migrations with reference to migrations of the highly educated population, while the stress is on economic theories, although some of them are closely connected to sociological, geographical and anthropological theories. The development of the theory on international migrations has been started by micro theoretical models, namely, through the conceptualization of theories which place the individual in the focal point of research, who estimates the positive, namely negative sides of moving from one location to another. Economic models on the micro theoretical level cede more space to models of macro structure which research the social and economic structure within and between countries. There are many theoretical models which offer possible answers to the question on what are the main determinants of international migrations on the macro analytical level. Although every one of them tries to give an answer to the same question, they use different concepts, assumptions and frameworks of research. The reasons which bring about the initiation of international migrations can be

  16. The role of language in shaping international migration

    Science.gov (United States)

    Adserà, Alícia; Pytliková, Mariola

    2016-01-01

    This paper examines the importance of language in international migration from multiple angles by studying the role of linguistic proximity, widely spoken languages, linguistic enclaves and language-based immigration policy requirements. To this aim we collect a unique dataset on immigration flows and stocks in 30 OECD destinations from all world countries over the period 1980–2010, and construct a set of linguistic proximity measures. Migration rates increase with linguistic proximity and with English at destination. Softer linguistic requirements for naturalization and larger linguistic communities at destination encourage more migrants to move. Linguistic proximity matters less when local linguistic network are larger. PMID:27330195

  17. International migration and New Zealand labour markets.

    Science.gov (United States)

    Farmer, R S

    1986-06-01

    "This paper seeks to assess the value of the overseas-born members of the labour force in ensuring a flexible labour supply in New Zealand since the beginning of the 1970s. Three main issues are considered: first, the role of the labour market in New Zealand's immigration policy; second, international migration trends and the labour market; and third, the evidence on migration and labour market segmentation in New Zealand." Data used are from official external migration statistics, quinquennial censuses, and recent research. The author notes that "in New Zealand immigration measures are currently being taken that emphasize that immigration continues to add to the flexibility of the labour market while uncontrolled emigration is a major cause of labour market instability." (SUMMARY IN FRE AND SPA) excerpt

  18. Impacts on International Migration and Remittances Growth

    Directory of Open Access Journals (Sweden)

    Ferdous Alam

    2011-01-01

    Full Text Available Problem statement: This study provided a brief discussion of the international migration, an age old common phenomenon is an emerging economic development issue and remittances growth. Approach: Each year Bangladesh exports huge number of labours abroad for foreign currency, called remittance. In the last four decades remittances played a major role to eradicate the poverty level in Bangladesh and it has experienced positive economic changes in Bangladesh. Now a day’s migration has been a common livelihood strategy of Bangladeshi people. Results: It contributed for the development of both sending and receiving countries as well as contributed at family level and community level. At family level, migration may improve household earnings, food, health, housing and educational standards. At the community level, improvement could be noticed in health, education, sanitation and infrastructure benefiting both migrants and non-migrant households. Conclusion: The aim of this study was to highlight and clarify the impacts on international migration and remittances growth in Bangladesh.

  19. Friendship and Internal Migration in Brazil: Vulnerability and Coping

    National Research Council Canada - National Science Library

    Agnaldo Garcia; Tayssa Grassi Rodrigues; Lorena Schettino Lucas; Daniela Marisol Pérez-Angarita

    2017-01-01

    Friendship has been investigated in the context of international migration, but little is known about the subject in relation to internal migration, a phenomenon of great social importance in Brazil...

  20. Institutional Determinants of International Migration from Central-Eastern Europe

    Directory of Open Access Journals (Sweden)

    Agnieszka FIHEL

    2007-04-01

    Full Text Available The aim of this paper is to present the role of institutional determinants for international migration from Central and Eastern Europe. In the whole post-war period international mobility has been stimulated by economic incentives, such as income disparities and unemployment, and also by particular solutions in migration policies in the receiving countries. Ethnic and asylum procedures, selective labor recruitments, visas barriers, regularization programs have mostly directed and intensified labor migration from CEE countries.Recently the EU enlargement (and, consequently, opening of member states’ labor markets became another institutional enhancement for migrating. The 2004 accession of eight CEE countries has been followed by a massive flow from CEE to the UK and Ireland that, together with Sweden, opened their labor markets for migrant workers. In 2007 Bulgaria and Romania will gain the access into EU, but the directions of mobility has been already established for Romanian and Bulgarian citizens: the main destination countries are Italy and Spain. The dynamics of migration from Romania and Bulgaria to South Europe has been extraordinary high since around 2000, mainly due to low legislative barriers and high demand for low-paid work. Again, the institutional determinant, such as overall acceptance towards illegal, foreign workers and regularization programs, turned out to be decisive.

  1. International Migration and its Effects on Family

    Directory of Open Access Journals (Sweden)

    Cornel Constantinescu

    2008-03-01

    Full Text Available The crises period that still cross Romania explain, between others, the apparition and development of international migration, after 1990. In a world marked by globalization, migration can not disappear, contrary, it grows bigger ant it remains an interesting subject in future. A study about migration consequences on family, specially on children’s personality left in the country, is justified because migration is a present phenomena in Romanian space at the beginning of the XXIth century. We try to analyse the effects of this phenomenon on family. Related to these goal we offer the conclusions obtained from a research realized in Campulung Muscel municipality, Arges county, on a lot of pupils that have parents left in foreign countries and the results to the investigation made in Pitesti municipality. The research showed that it is a relationship between children’s marks at school and parent’s leaving; children’s perceptions on parent’s leaving; identifies school’s interest level in diminution of the low school performance effects caused by this socio-economical phenomena.

  2. Domestic and International Climate Migration from Rural Mexico.

    Science.gov (United States)

    Nawrotzki, Raphael J; Runfola, Daniel M; Hunter, Lori M; Riosmena, Fernando

    2016-12-01

    Evidence is increasing that climate change and variability may influence human migration patterns. However, there is less agreement regarding the type of migration streams most strongly impacted. This study tests whether climate change more strongly impacted international compared to domestic migration from rural Mexico during 1986-99. We employ eight temperature and precipitation-based climate change indices linked to detailed migration histories obtained from the Mexican Migration Project. Results from multilevel discrete-time event-history models challenge the assumption that climate-related migration will be predominantly short distance and domestic, but instead show that climate change more strongly impacted international moves from rural Mexico. The stronger climate impact on international migration may be explained by the self-insurance function of international migration, the presence of strong migrant networks, and climate-related changes in wage difference. While a warming in temperature increased international outmigration, higher levels of precipitation declined the odds of an international move.

  3. The Role of Language in Shaping International Migration

    DEFF Research Database (Denmark)

    Pytlikova, Mariola; Adsera, Alicia

    and/or widely spoken languages (or ease to quickly learn it) plays a key role in the transfer of human capital from the source country to another country and boosts the immigrant’s success at the destination’s labor market. We use data on immigration flows and stocks of foreigners in 27 OECD...... and climate shocks, migrant networks, language and aspects of “cultural distance”. In that regard, the more “foreign” or distant the new culture and the larger the language barriers, the higher the costs are for an individual to migrate to a particular destination. Fluency in destination country’s language...... destination countries from 130 source countries for the years 1985–2006 to study the role of language in shaping international migration. In addition to standard covariates from gravity models, we include a set of indices of language proximity to study their association to the observed flows: (1) a newly...

  4. International Migration with Heterogeneous Agents: Theory and Evidence

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Brücker, Herbert

    of German migration stocks and flows since 1967. We find that (i) panel-unit root tests reject the hypothesis that migration flows and the explanatory variables are integrated of the same order, while migration stocks and the explanatory variables are all I(1) variables, and (ii) the hypothesis......Temporary migration, though empirically relevant, is often ignored in formal models. This paper proposes a migration model with heterogeneous agents and persistent cross country income differentials that features temporary migration. In equilibrium there exists a positive relation between the stock...... of migrants and the income differential, while the net migration flow becomes zero. Consequently, existing empirical migration models, estimating net migration flows, instead of stocks, may be misspecified. This suspicion appears to be confirmed by our investigation of the cointegration relationships...

  5. Migration in far west Nepal: intergenerational linkages between internal and international migration of rural-to-urban migrants.

    Science.gov (United States)

    Poertner, Ephraim; Junginger, Mathias; Müller-Böker, Ulrike

    2011-01-01

    In Nepal, international labor migration to India and overseas, as well as internal migration to the rural Nepalese lowlands, is of high socioeconomic significance. Scholarly debates about migration in Nepal have gradually shifted from an economic to a more holistic perspective, also incorporating social dimensions. However, little evidence has been generated about internal migration to urban destinations and the potential linkages between international and internal migration. This article draws on Bourdieu's “Theory of Practice” and sees migration as a social practice. Accordingly, migration practice is regarded as a strategy social agents apply to increase or transfer capitals and ultimately secure or improve their social position. Evidence for this argument is based on a qualitative case study of rural to urban migrants in Far West Nepal conducted in July and August 2009. The study at hand addresses linkages between internal and international migration practices and provides insight about a social stratum that is often neglected in migration research: the middle class and, more precisely, government employees. The authors show that social relations are crucial for channeling internal migration to a specific destination. Furthermore, they unveil how internal migration is connected to the international labor migration of former generations. Finally, the authors examine how migration strategies adopted over generations create multi-local social networks rooted in the family's place of origin.

  6. Mapping internal connectivity through human migration in malaria endemic countries.

    Science.gov (United States)

    Sorichetta, Alessandro; Bird, Tom J; Ruktanonchai, Nick W; Zu Erbach-Schoenberg, Elisabeth; Pezzulo, Carla; Tejedor, Natalia; Waldock, Ian C; Sadler, Jason D; Garcia, Andres J; Sedda, Luigi; Tatem, Andrew J

    2016-08-16

    Human mobility continues to increase in terms of volumes and reach, producing growing global connectivity. This connectivity hampers efforts to eliminate infectious diseases such as malaria through reintroductions of pathogens, and thus accounting for it becomes important in designing global, continental, regional, and national strategies. Recent works have shown that census-derived migration data provides a good proxy for internal connectivity, in terms of relative strengths of movement between administrative units, across temporal scales. To support global malaria eradication strategy efforts, here we describe the construction of an open access archive of estimated internal migration flows in endemic countries built through pooling of census microdata. These connectivity datasets, described here along with the approaches and methods used to create and validate them, are available both through the WorldPop website and the WorldPop Dataverse Repository.

  7. The International Organization for Migration in Global Migration Governance

    OpenAIRE

    2011-01-01

    This project focuses on the IOM, the notion of global governance of migration and the interaction between these two. The point of departure has been an attempt to grasp the current global approach to migration and comprehend whether, or to what degree, there is governance of migration issues taking place at a global level.

  8. International migration and development in Mexican communities.

    Science.gov (United States)

    Durand, J; Kandel, W; Parrado, E A; Massey, D S

    1996-05-01

    The theoretical and empirical literature generally regards international migration as producing a cycle of dependency and stunted development in sending communities. Most migrants' earnings are spent on consumption; few funds are channeled into productive investment. We argue that this view is misleading because it ignores the conditions under which productive investment is likely to be possible and profitable. We analyze the determinants of migrants' savings and remittance decisions, using variables defined at the individual, household, community, and macroeconomic levels. We identify the conditions under which U.S. earnings are repatriated to Mexico as remittances and savings, and indicate the factors leading to their productive investment.

  9. Internal Migration and Citizenship Education in China's Shenzhen City

    Science.gov (United States)

    Ye, Wangbei

    2016-01-01

    Migration's influences on citizenship education were widely discussed in the literature. However, most studies were based on international migration that drew experience from, for example, North America and Europe. Less attention was paid to internal migration or developing areas. This article takes China as an example, which is a country that has…

  10. Internal Migration and Citizenship Education in China's Shenzhen City

    Science.gov (United States)

    Ye, Wangbei

    2016-01-01

    Migration's influences on citizenship education were widely discussed in the literature. However, most studies were based on international migration that drew experience from, for example, North America and Europe. Less attention was paid to internal migration or developing areas. This article takes China as an example, which is a country that has…

  11. Nursing shortages and international nurse migration.

    Science.gov (United States)

    Ross, S J; Polsky, D; Sochalski, J

    2005-12-01

    The United Kingdom and the United States are among several developed countries currently experiencing nursing shortages. While the USA has not yet implemented policies to encourage nurse immigration, nursing shortages will likely result in the growth of foreign nurse immigration to the USA. Understanding the factors that drive the migration of nurses is critical as the USA exerts more pull on the foreign nurse workforce. To predict the international migration of nurses to the UK using widely available data on country characteristics. The Nursing and Midwifery Council serves as the source of data on foreign nurse registrations in the UK between 1998 and 2002. We develop and test a regression model that predicts the number of foreign nurse registrants in the UK based on source country characteristics. We collect country-level data from sources such as the World Bank and the World Health Organization. The shortage of nurses in the UK has been accompanied by massive and disproportionate growth in the number of foreign nurses from poor countries. Low-income, English-speaking countries that engage in high levels of bilateral trade experience greater losses of nurses to the UK. Poor countries seeking economic growth through international trade expose themselves to the emigration of skilled labour. This tendency is currently exacerbated by nursing shortages in developed countries. Countries at risk for nurse emigration should adjust health sector planning to account for expected losses in personnel. Moreover, policy makers in host countries should address the impact of recruitment on source country health service delivery.

  12. Does human migration affect international trade? A complex-network perspective.

    Directory of Open Access Journals (Sweden)

    Giorgio Fagiolo

    Full Text Available This paper explores the relationships between international human migration and merchandise trade, using a complex-network approach. We firstly compare the topological structure of worldwide networks of human migration and bilateral trade over the period 1960-2000. Next, we ask whether the position of any pair of countries in the migration network affects their bilateral trade flows. We show that: (i both weighted and binary versions of the networks of international migration and trade are strongly correlated; (ii such correlations can be mostly explained by country economic/demographic size and geographical distance; and (iii pairs of countries that are more central in the international-migration network trade more. Our findings suggest that bilateral trade between any two countries is not only affected by the presence of migrants from either countries but also by their relative embeddedness in the complex web of corridors making up the network of international human migration.

  13. Does human migration affect international trade? A complex-network perspective.

    Science.gov (United States)

    Fagiolo, Giorgio; Mastrorillo, Marina

    2014-01-01

    This paper explores the relationships between international human migration and merchandise trade, using a complex-network approach. We firstly compare the topological structure of worldwide networks of human migration and bilateral trade over the period 1960-2000. Next, we ask whether the position of any pair of countries in the migration network affects their bilateral trade flows. We show that: (i) both weighted and binary versions of the networks of international migration and trade are strongly correlated; (ii) such correlations can be mostly explained by country economic/demographic size and geographical distance; and (iii) pairs of countries that are more central in the international-migration network trade more. Our findings suggest that bilateral trade between any two countries is not only affected by the presence of migrants from either countries but also by their relative embeddedness in the complex web of corridors making up the network of international human migration.

  14. Heterogeneous effects of international migration: evidences from Bangladesh.

    OpenAIRE

    Traverso, Silvio

    2016-01-01

    Despite the general consensus regarding the important role played by international migration in the development of Bangladesh, little has been done to quantitatively estimate its effects. Within the framework of Rubin's causal model, this paper contributes to the literature estimating the net impact of international migration on the welfare of the members of households with migration experience. By taking advantage of the non-parametric nature of matching estimators, the effect of migration i...

  15. Internal migration, regional labor markets and the role of agglomeration economies

    DEFF Research Database (Denmark)

    Mitze, Timo Friedel; Schmidt, Torben Dall

    2015-01-01

    with human capital as well as the region’s employment share of knowledge-intensive services are positively correlated with the region’s net in-migration rate. Regarding the regional implications of internal migration flows, the results hint at a process of cumulative causation for the time period of analysis...

  16. Comparing internal migration across the countries of Latin America: A multidimensional approach.

    Science.gov (United States)

    Bernard, Aude; Rowe, Francisco; Bell, Martin; Ueffing, Philipp; Charles-Edwards, Elin

    2017-01-01

    While considerable progress has been made in understanding the way particular aspects of internal migration, such as its intensity, age profile and spatial impact, vary between countries around the world, little attention to date has been given to establishing how these dimensions of migration interact in different national settings. We use recently developed measures of internal migration that are scale-independent to compare the overall intensity, age composition, spatial impact, and distance profile of internal migration in 19 Latin American countries. Comparisons reveal substantial cross-national variation but cluster analysis suggests the different dimensions of migration evolve systematically to form a broad sequence characterised by low intensities, young ages at migration, unbalanced flows and high friction of distance at lower levels of development, trending to high intensities, an older age profile of migration, more closely balanced flows and lower friction of distance at later stages of development. However, the transition is not linear and local contingencies, such as international migration and political control, often distort the migration-development nexus, leading to unique migration patterns in individual national contexts.

  17. THE MULTI-LEVEL GOVERNANCE OF INTERNATIONAL MIGRATION

    OpenAIRE

    2015-01-01

    The article provides the history of legal framework of regulating migration processes on the global level. The author analyzes the dual nature of migration policy on the regional, national and global levels, which occurs when interests of different parties involved in international relations do not coincide. Recommendations are given on ways to improve the regulation of migration processes.

  18. International Family Migration and the Dual-Earner Model

    DEFF Research Database (Denmark)

    Munk, Martin D.; Nikolka, Till; Poutvaara, Panu

    2017-01-01

    We study the impact of international migration on labor force participation and household economies of couples, based on a survey of Danish emigrants. We find that migration is associated with reduced female labor force participation, especially among couples migrating to the United States. Most...

  19. The measurement of international migration in Belgium.

    Science.gov (United States)

    Poulain, M

    1987-01-01

    This article examines legislation affecting international migration in Belgium from the perspective of 2 questions: 1) What types of migrants are definable by legislation? and 2) What kinds of documents may be utilized to compile statistics on international migration? The following are some of the article's main points. 1) Since January 1, 1847 each communal administration in Belgium has maintained a national population register that details births, deaths, marriages and household structures, and all movements within 1 commune, from 1 commune to another, and movements between states. 2) When a Belgian citizen leaves for a foreign destination with the intention of settling there, his name is struck from the registers. 3) To enter Belgian territory, the alien must possess the documents required under bilateral agreements between Belgium and each of the states concerned. Generally, the alien must obtain a visa to his passport from 1 of the diplomatic or consular offices of Benelux before entering Belgium. The alien must have sufficient means of subsistence to avoid being considered in need. He must not be listed as an undesirable alien in Belgium, he must not have been convicted of a crime, and he must not constitute a danger to public order or national security, The alien also should not have been expelled from Belgium less than 10 years earlier. 4) Absence from Belgium and the right to return is granted to aliens holding a valid certificate of enrollment or a settlement card. 5) Any individual who has reason to fear persecution can obtain refugee status; his stay is protected until his application is declared to be unfounded by the High Commission. 6) The National Statistical Institute issues various types of data from which international population movements can be identified. The 2 main sources of these statistics are the population censuses held every 10 years and the annual demographic statistics. 7) In 1967, the Belgian Council of Ministers authorized the

  20. Internal migration, international migration, and physical growth of left-behind children: A study of two settings.

    Science.gov (United States)

    Lu, Yao

    2015-11-01

    Parental out-migration has become a common experience of childhood worldwide and tends to have important ramifications for child development. There has been much debate on whether overall children benefit or suffer from parental out-migration. The present study examines how the relationship between parental out-migration and children's growth differs by the type of migration (internal vs. international). This comparison is conducted in two diverse settings, Mexico and Indonesia. Data are from two national longitudinal surveys: the Mexican Family Life Survey and the Indonesian Family Life Survey. Results from fixed-effect regressions show that international migration tends to have a less beneficial, sometimes even more detrimental, impact on the growth of children left behind than internal migration. Results also reveal contextual differences in the role of parental out-migration. Possible explanations are discussed.

  1. A probe into reasons for international migration in Fujian Province.

    Science.gov (United States)

    Zhu, G

    1990-01-01

    In this paper, the author discusses the extent of international migration from China's Fujian Province and considers the reasons behind the migration. The most recent estimates place China's overseas population at 22.1 million, 19 million (88%) of which are concentrated in Southeast Asia. According to the author's calculations, at least 7 million of the Chinese overseas population are of Fujian descent. Indonesia alone holds some 3.3 million Fujianese. Malaysia, Singapore, and the Philippines account for most of the remaining Fujianese overseas population. Having established the extent of international migration from the Fujian Province, the author attempts to establish the reasons behind it. The author first considers the historical origins of Fujianese international migration, from its early states (end century B.C.-17th century) to modern times *18-early 20th century) to the current period (1949-present). The author then examines the reasons behind the migration, primarily the social environment and individual behavior. Finally, the author provides categories of international migration, stressing that these categories often overlap or coincide. Most of the early migration was "spontaneous" -- essentially, an unplanned occurrence. During the modern period, most migration was "forced" by the contract labor system instituted by colonialists. Political and social upheaval also prompted "provoked" international migration. And following the Chinese Revolution, "free" migration allowed many to return home or to join relative abroad.

  2. Migration, relationship capital and international travel : theory and evidence

    NARCIS (Netherlands)

    McCann, Philip; Poot, Jacques; Sanderson, Lynda

    2010-01-01

    In this article we consider how international migration is related to the frequency and duration of trips to the home country. For many migrants, international migration triggers a series of trips to visit the home country that allow for a replenishment of the depleted relationship capital with fami

  3. Epigenetic signatures of internal migration in Italy.

    Science.gov (United States)

    Campanella, Gianluca; Polidoro, Silvia; Di Gaetano, Cornelia; Fiorito, Giovanni; Guarrera, Simonetta; Krogh, Vittorio; Palli, Domenico; Panico, Salvatore; Sacerdote, Carlotta; Tumino, Rosario; Elliott, Paul; Matullo, Giuseppe; Chadeau-Hyam, Marc; Vineis, Paolo

    2014-10-15

    Observational studies have suggested that the risks of non-communicable diseases in voluntary migrants become similar to those in the host population after one or more generations, supporting the hypothesis that these diseases have a predominantly environmental (rather than inherited) origin. However, no study has been conducted thus far to identify alterations at the molecular level that might mediate these changes in disease risk after migration. Using genome-wide DNA methylation profiles from more than 1000 Italian participants, we conducted an epigenome-wide association study (EWAS) to identify differences between south-to-north migrants and their origin (southern natives) and host (north-western natives) populations. We identified several differentially methylated CpG loci, in particular when comparing south-to-north migrants with north-western natives. We hypothesise that these alterations may underlie an adaptive response to exposure differentials that exist between origin and host populations. Our study is the first large agnostic investigation of DNA methylation changes linked to migratory processes, and shows the potential of EWAS to investigate their biological effects. © The Author 2014; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

  4. Bayesian Probabilistic Projection of International Migration.

    Science.gov (United States)

    Azose, Jonathan J; Raftery, Adrian E

    2015-10-01

    We propose a method for obtaining joint probabilistic projections of migration for all countries, broken down by age and sex. Joint trajectories for all countries are constrained to satisfy the requirement of zero global net migration. We evaluate our model using out-of-sample validation and compare point projections to the projected migration rates from a persistence model similar to the method used in the United Nations' World Population Prospects, and also to a state-of-the-art gravity model.

  5. Theoretical foundations of international migration process studies: analysis of key migration theories development

    Directory of Open Access Journals (Sweden)

    Shymanska K.V.

    2017-03-01

    Full Text Available The need for transformation of Ukraine's migration policy based on globalized world development trends and in response to the challenges of European integration transformations causes the need of researching the theoretical and methodological basis of migration studies, and the regulations of existing theories of international migration. The bibliometric analysis of scientific publications on international migration in cites indexes found that the recent researches on these problems acquire interdisciplinary character. It necessitates the transformation of migration study approaches basing on economic, social, institutional theories and concepts synthesis. The article is devoted to the study of theoretical regulations of existing international migration theories in the context of the evolution of scientists’ views on this phenomenon. The author found that the existing theories of international migration should be divided into three categories (microeconomic, macroeconomic, globalizational that contributes to their understanding in the context of implementation possibilities in migrational public administration practice. It allows to determine the theories which should be used for Ukrainian state migration policy constructing and eliminating or reducing the external migration negative effects.

  6. Socio-Economic Determinants of International Migration

    Directory of Open Access Journals (Sweden)

    Yaroslav PRYTULA

    2012-05-01

    Full Text Available Since economic factors cannot fully explain the determinants of bilateral migration, this study explores the social and cultural determinants that influence an individual’s decision to migrate. Values, norms and interests in a given culture, may determine whether an individual’s intention to move translates into actual migration. Work values inherent in different cultures could explain why people move or do not move under the condition of perceived economic advantages of migration. A gravity type migration model is used to incorporate variables related both to economic indicators and work values. It is perhaps the first migration study to use the World Value Survey (WVS and the European Value Survey (EVS. We use 2000 stock bilateral migration dataset collected by the World Bank. Our findings indicate that if more aspects of work are valued in a country, this country sends more migrants. Also we show that countries with higher extrinsic work value orientation tend to send more migrants, while countries with higher intrinsic work value orientation tend to send fewer migrants. Our finding shows that the value of work and the level of job security in a country may significantly change migration decision.

  7. International nurse migration: lessons from the Philippines.

    Science.gov (United States)

    Brush, Barbara L; Sochalski, Julie

    2007-02-01

    Developed countries facing nursing shortages have increasingly turned to aggressive foreign nurse recruitment, primarily from developing nations, to offset their lagging domestic nurse supplies and meet growing health care demands. Few donor nations are prepared to manage the loss of their nurse workforce to migration. The sole country with an explicit nurse export policy and the world's leading donor of nurse labor - the Philippines - is itself facing serious provider maldistribution and countrywide health disparities. Examining the historical roots of Philippines nurse migration provides lessons from which other nurse exporting countries may learn. The authors discuss factors that have predicated nurse migration and policies that have eased the way. Furthermore, the authors analyze how various stakeholders influence migratory patterns, the implications of migration for nurses and the public in their care, and the challenges that future social policy and political systems face in addressing global health issues engendered by unfettered recruitment of nurses and other health workers.

  8. Gender and Internal Migration dynamics in Ghana

    African Journals Online (AJOL)

    Agribotix GCS 068

    Gender roles, relations and inequalities affects who migrates and why ... roles and responsibilities to women's benefit. However ..... of lower and middle level officers in Ghana's public service and certainly several times higher than what they ...

  9. Nurses across borders: foregrounding international migration in nursing history.

    Science.gov (United States)

    Choy, Catherine Ceniza

    2010-01-01

    Although the international migration of nurses has played a formative role in increasing the racial and ethnic diversity of the health care labor force, nursing historians have paid very little attention to the theme of international migration and the experiences of foreign-trained nurses, A focus on international migration complements two new approaches in nursing history: the agenda to internationalize its frameworks, and the call to move away from "great women, great events" and toward the experiences of "ordinary" nurses. This article undertakes a close reading of the life and work of Filipino American nurse Ines Cayaban to reconceptualize nursing biography in an international framework that is attentive to issues of migration, race, gender, and colonialism. It was a Hannah keynote lecture delivered by the author on June 5, 2008, as part of the CAHN/ACHN (Canadian Association for the History of Nursing/Association Canadienne pour l'Histoire du Nursing) International Nursing History Conference.

  10. International migration: an assessment for the '90s.

    Science.gov (United States)

    Tomasi, S M

    1989-01-01

    A quarter century ago, the world of international migration looked much different than it does today. International migration was then favorable regarded in many parts of the world. Today, this mood has soured. Guestworkers in Germany in 1989, particularly Turks, are the subject of widespread hostility and a growing anti-immigrant political party. France, too, has developed a significant anti-immigrant political party and now facilitates the repatriation of unemployed Algerian nationals with cash assistance. In the US, a chapter thought closed forever in 1964 might well be reopened as the federal government, in 1989, will decide whether or not to admit replenishment agricultural workers. In the Arab region, the Palestine Liberation Organization was created in 1964 to represent one of the world's largest refugee population - the 1 million Palestinians who fled during the 1'947-1949 fighting and their offspring. Today, Africa contains an estimated 4-5 million refugees. In Asia, the Gulf of Tonkin crisis in 1964 served as a pretext to escalate the war in Indochina that would create millions of refugees. Little concern was expressed 25 years ago about illegal migration from developing countries. Asia, Africa, and Latin America seemed to lie outside the usual path of international migration. A conference on international migration was held at Bellagio, Italy, in July 1988. The contributions comprising this volume were presented at the Bellagio Conference. Each contribution approaches the subject matter of international migration from a distinctive theoretical, disciplinary, or thematic perspective. This volume therefore reflects a large measure of the scholarly diversity that coexists in international migration studies. One of the themes of the conference is the realization that states vitally affect international migration and are greatly affected by the phenomenon. The Bellagio conferees also agreed on the importance of comparative research to greater scientific

  11. Native Internal Migration and the Labor Market Impact of Immigration

    Science.gov (United States)

    Borjas, George J.

    2006-01-01

    This paper presents a theoretical and empirical study of how immigration influences the joint determination of the wage structure and internal migration behavior for native-born workers in local labor markets. Using data from the 1960-2000 decennial censuses, the study shows that immigration is associated with lower in-migration rates, higher…

  12. Native Internal Migration and the Labor Market Impact of Immigration

    Science.gov (United States)

    Borjas, George J.

    2006-01-01

    This paper presents a theoretical and empirical study of how immigration influences the joint determination of the wage structure and internal migration behavior for native-born workers in local labor markets. Using data from the 1960-2000 decennial censuses, the study shows that immigration is associated with lower in-migration rates, higher…

  13. Empirical research on international environmental migration: a systematic review.

    Science.gov (United States)

    Obokata, Reiko; Veronis, Luisa; McLeman, Robert

    2014-01-01

    This paper presents the findings of a systematic review of scholarly publications that report empirical findings from studies of environmentally-related international migration. There exists a small, but growing accumulation of empirical studies that consider environmentally-linked migration that spans international borders. These studies provide useful evidence for scholars and policymakers in understanding how environmental factors interact with political, economic and social factors to influence migration behavior and outcomes that are specific to international movements of people, in highlighting promising future research directions, and in raising important considerations for international policymaking. Our review identifies countries of migrant origin and destination that have so far been the subject of empirical research, the environmental factors believed to have influenced these migrations, the interactions of environmental and non-environmental factors as well as the role of context in influencing migration behavior, and the types of methods used by researchers. In reporting our findings, we identify the strengths and challenges associated with the main empirical approaches, highlight significant gaps and future opportunities for empirical work, and contribute to advancing understanding of environmental influences on international migration more generally. Specifically, we propose an exploratory framework to take into account the role of context in shaping environmental migration across borders, including the dynamic and complex interactions between environmental and non-environmental factors at a range of scales.

  14. The influence of attitudes toward immigrants on international migration

    DEFF Research Database (Denmark)

    Gorinas, Cedric; Pytlikova, Mariola

    2015-01-01

    We investigate whether anti-immigrant attitudes reduce migrant inflows in OECD countries. Using comprehensive data on international migration and natives’ attitudes, we find that natives’ hostility, when captured with natives’ propensity to discriminate against immigrants on the labor market...

  15. The Analysis of International Migration towards Economic Growth

    OpenAIRE

    Ferdous Alam; Chamhuri Siwar; Basri Talib; Rabiul Islam

    2011-01-01

    Problem statement: This study discusses the analysis of international migration towards economic growth in Bangladesh. International migration refers to the cross-border movement of people from a mother country to a location outside that mother country, with the purpose of taking up higher income employment, better living conditions, higher education get access to civic amenities and conducting a daily existence there for an extended period of time. The exports of labor, human capital, play a...

  16. A new area classification for understanding internal migration in Britain.

    Science.gov (United States)

    Dennett, Adam; Stillwell, John

    2011-01-01

    This article details the development of a new area classification for Britain based on internal migration variables taken from the 2001 Census. An explanation of why general-purpose area classifications already in existence are not ideal for internal migration analysis is provided, before an account of the construction of the new classification is given. The latter involves justification of the choice of variables, explanation of the methodology adopted and presentation of the final typology.

  17. India–EU engagement and international migration: Historical perspectives, future challenges, and policy imperatives

    Directory of Open Access Journals (Sweden)

    Basant Kumar Potnuru

    2015-03-01

    Full Text Available In the absence of a multilateral framework and a rule based global structure for the governance of international migration of people in all its complexities, countries engage in bilateral or regional cooperation in an attempt to engage and harmonize international movements and work towards a win–win situation. The current paper examines if and how the bilateral relationship or engagement between India and the EU has historically evolved and influenced international migration flows between them, and what potential future challenges and policy options they face for a successful engagement and facilitation of movement of people.

  18. [Dentists' workforce in Hungary and international migration].

    Science.gov (United States)

    Balázs, Péter

    2012-06-01

    In Hungary, cross-national migration in dental care was performed rather by patients from abroad instead of the domestic dentists' migration for working abroad. Actually, this tacitly realized and so-called dental tourism experienced two basic changes. The National Medical Tourism Ltd. arranged the First Conference for Development of Dental Tourism on 21 April 2011. Hungary's prime minister addressed the meeting and finally signed an agreement with the organizing Ltd. about governmental financial support for development of dental tourism. On the other hand, Germany and Austria deleted all restrictions against the free cross-national workforce migration since 1 May this year. For understanding and prognosis of dentists' future migration, it is inevitable to collect and analyse relevant data of the previous years. This study is presenting data obtained from January 1, 2006 to December 31, 2010. According to the net outcome, the dentists' human resource system was balanced down to the end of 2010. However, this state is unsure even for the near future, thus preventing the deficit of dentists all necessary measures must be taken to keep up the present level of the domestic dentral service.

  19. STRUCTURAL ECONOMIC CHANGE AND INTERNATIONAL MIGRATION FROM MEXICO AND POLAND.

    Science.gov (United States)

    Massey, Douglas S; Kalter, Frank; Pren, Karen A

    2008-01-01

    In this article we use uniquely comparable data sets from two very different settings to examine how exogenous economic transformations affect the likelihood and selectivity of international out-migration. Specifically, we use data from the Mexican Migration Project to construct event history files predicting first U.S. trips from seven communities in the state of Veracruz, which until recently sent very few migrants abroad. Similarly, using data from the Polish Migration Project, we derive comparable event history files predicting first trips to Germany from four Polish communities, which also sent few migrants abroad before the 1980s. Our analyses suggest that the onset of structural adjustment in both places had a significant effect in raising the probability of international migration, even when controlling for a set of standard variables specified by other theories to influence migration propensity, such as the size of the binational income gap and various indicators of human and social capital.

  20. The Analysis of International Migration towards Economic Growth

    Directory of Open Access Journals (Sweden)

    Ferdous Alam

    2011-01-01

    Full Text Available Problem statement: This study discusses the analysis of international migration towards economic growth in Bangladesh. International migration refers to the cross-border movement of people from a mother country to a location outside that mother country, with the purpose of taking up higher income employment, better living conditions, higher education get access to civic amenities and conducting a daily existence there for an extended period of time. The exports of labor, human capital, play a major role to minimize the poverty level in Bangladesh. In the last four decades, Bangladesh exports the huge number of labors abroad for economic growth through remittances. Remittances affect poverty eradication most directly by increasing the income of households which have a family member working abroad. Because income from remittances is usually larger than that which could have been earned by migrants they stayed at home. Approach: The aim of this study is to highlight the policy implications for the maximization of international migration and the analysis of economic growth in Bangladesh. The data for analysis is perceived from the secondary sources. The significant manipulations for acquired data are migration of employment and remittances for economic growth in Bangladesh. Results: Migration contributed for the development of macro and micro level in Bangladesh. Conclusion: There would be potential benefits to world's poor if more international attention were focused on integrating migration policy to within the larger global dialogue economic development and poverty reduction. Strong institutions and good policies will enhance the benefits of human capital migration for Bangladesh.

  1. Human Insecurity: Understanding International Migration from A Human Security Perspective

    Directory of Open Access Journals (Sweden)

    Francesca Vietti

    2013-07-01

    Full Text Available This article examines contemporary, mass migration from the perspective of human security. It tracks the development of the human security model of international relations, and compares it to the well-established state security model that has served as the dominant paradigm for international relations since the seventeenth century. The article argues that human security offers a more effective approach to many of the underlying problems and threats associated with mass migration, than does the traditional state-security model.  It challenges national and international authorities to address threats to human security, in order to minimize forced migration and to create the conditions for migration by choice, not necessity.

  2. Characterizing the International Migration Barriers with a Probabilistic Multilateral Migration Model.

    Science.gov (United States)

    Li, Xiaomeng; Xu, Hongzhong; Chen, Jiawei; Chen, Qinghua; Zhang, Jiang; Di, Zengru

    2016-09-06

    Human migration is responsible for forming modern civilization and has had an important influence on the development of various countries. There are many issues worth researching, and "the reason to move" is the most basic one. The concept of migration cost in the classical self-selection theory, which was introduced by Roy and Borjas, is useful. However, migration cost cannot address global migration because of the limitations of deterministic and bilateral choice. Following the idea of migration cost, this paper developed a new probabilistic multilateral migration model by introducing the Boltzmann factor from statistical physics. After characterizing the underlying mechanism or driving force of human mobility, we reveal some interesting facts that have provided a deeper understanding of international migration, such as the negative correlation between migration costs for emigrants and immigrants and a global classification with clear regional and economic characteristics, based on clustering of migration cost vectors. In addition, we deconstruct the migration barriers using regression analysis and find that the influencing factors are complicated but can be partly (12.5%) described by several macro indexes, such as the GDP growth of the destination country, the GNI per capita and the HDI of both the source and destination countries.

  3. Characterizing the International Migration Barriers with a Probabilistic Multilateral Migration Model

    Science.gov (United States)

    Li, Xiaomeng; Xu, Hongzhong; Chen, Jiawei; Chen, Qinghua; Zhang, Jiang; di, Zengru

    2016-09-01

    Human migration is responsible for forming modern civilization and has had an important influence on the development of various countries. There are many issues worth researching, and “the reason to move” is the most basic one. The concept of migration cost in the classical self-selection theory, which was introduced by Roy and Borjas, is useful. However, migration cost cannot address global migration because of the limitations of deterministic and bilateral choice. Following the idea of migration cost, this paper developed a new probabilistic multilateral migration model by introducing the Boltzmann factor from statistical physics. After characterizing the underlying mechanism or driving force of human mobility, we reveal some interesting facts that have provided a deeper understanding of international migration, such as the negative correlation between migration costs for emigrants and immigrants and a global classification with clear regional and economic characteristics, based on clustering of migration cost vectors. In addition, we deconstruct the migration barriers using regression analysis and find that the influencing factors are complicated but can be partly (12.5%) described by several macro indexes, such as the GDP growth of the destination country, the GNI per capita and the HDI of both the source and destination countries.

  4. Characterizing the International Migration Barriers with a Probabilistic Multilateral Migration Model

    Science.gov (United States)

    Li, Xiaomeng; Xu, Hongzhong; Chen, Jiawei; Chen, Qinghua; Zhang, Jiang; Di, Zengru

    2016-01-01

    Human migration is responsible for forming modern civilization and has had an important influence on the development of various countries. There are many issues worth researching, and “the reason to move” is the most basic one. The concept of migration cost in the classical self-selection theory, which was introduced by Roy and Borjas, is useful. However, migration cost cannot address global migration because of the limitations of deterministic and bilateral choice. Following the idea of migration cost, this paper developed a new probabilistic multilateral migration model by introducing the Boltzmann factor from statistical physics. After characterizing the underlying mechanism or driving force of human mobility, we reveal some interesting facts that have provided a deeper understanding of international migration, such as the negative correlation between migration costs for emigrants and immigrants and a global classification with clear regional and economic characteristics, based on clustering of migration cost vectors. In addition, we deconstruct the migration barriers using regression analysis and find that the influencing factors are complicated but can be partly (12.5%) described by several macro indexes, such as the GDP growth of the destination country, the GNI per capita and the HDI of both the source and destination countries. PMID:27597319

  5. 2007 Estimated International Energy Flows

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C A; Belles, R D; Simon, A J

    2011-03-10

    An energy flow chart or 'atlas' for 136 countries has been constructed from data maintained by the International Energy Agency (IEA) and estimates of energy use patterns for the year 2007. Approximately 490 exajoules (460 quadrillion BTU) of primary energy are used in aggregate by these countries each year. While the basic structure of the energy system is consistent from country to country, patterns of resource use and consumption vary. Energy can be visualized as it flows from resources (i.e. coal, petroleum, natural gas) through transformations such as electricity generation to end uses (i.e. residential, commercial, industrial, transportation). These flow patterns are visualized in this atlas of 136 country-level energy flow charts.

  6. Migration Trends in the Kansas Ogallala Region and the Internal Colonial Dependency Model.

    Science.gov (United States)

    White, Stephen E.

    1998-01-01

    Examines population change in the High Plains of western Kansas in terms of an internal colonialism-dependency model. Identifies a wide range of colonial dependent characteristics, including long-term population decline, high median age, highly channelized migration flows, and continuing outmigration of the region's most educated inhabitants.…

  7. International and internal migration measured from the School Census in England.

    Science.gov (United States)

    Simpson, Ludi; Marquis, Naomi; Jivraj, Stephen

    2010-01-01

    The School Census is the only regularly updated dataset covering almost all of the population of a specific age, which records changes of address along with ethnicity and some family economic circumstances. It can be used to measure internal and international family migration as shown in this report. The School Census is suited to identify and quantify new local migration streams between censuses, successfully identifying the local distribution of Eastern European immigration in the decade since 2000. The measures do not provide a complete measure of migration, either internally or internationally. The exclusion of those outside the state school system means that internal migration is under-estimated, and international migration is approximately measured. The advantages of the School Census are its frequent updates, its fine geographical information, and its indicators of ethnicity and low family income, which powerfully complement other sources.

  8. International labor migration and external debt.

    Science.gov (United States)

    Bustamante, J A

    1987-01-01

    The prevailing Mexican and US definitions of undocumented migration are poles apart. The US views it as a criminal problem. Mexicans view the undocumented migrants as actors in an economic game in which the rules are extremely disadvantageous to these migrants. Migrants themselves and their communities view the undocumented as a positive element. It is necessary to move toward a bilateral focus and bilateral negotiation on the issue of migratory workers. This proposal derives from several assumptions: 1) the external debt is a bilateral or multilateral issue, 2) it is important to avoid forcing debtor countries to choose between stimulating economic growth or making payment on their foreign debt, 3) prevailing public opinion in the US favors halting undocumented migration, 4) the US views the migration of undocumented Mexicans as the result of forces endogenous to Mexico and exogenous to the US, 5) the US views both Mexico's ability to make payment on its external debt and to halt emigration as tied to the Mexican government's ability or inability to reconcile political stability with scarce monetary resources, and 6) political instability in Mexico could augment emigration to the US and undermine Mexico's ability to address its foreign debt. The following proposal suggests means to link negotiation on the external debt to that of undocumented migration: 1) The Mexican government could reach an accord with the US to channel a portion of the actual interest on the external debt as a fund to be invested in Mexico to construct a system of labor intensive agroindustrial productive units designed to attract former or potential migratory workers; 2) the total amount of these funds would be deducted from interest payments on the principal of the actual external debt and redefined as an ad hoc loan to Mexico to finance these production units; 3) part of the production from these units would be incorporated into ongoing US food relief and food assistance programs; 4) the

  9. Internal migration, regional labor markets and the role of agglomeration economies

    DEFF Research Database (Denmark)

    Mitze, Timo Friedel; Schmidt, Torben Dall

    2015-01-01

    for the role of space–time dynamic adjustment processes and simultaneity among migration and labor market variables and finally test for heterogeneity in the migration response to regional labor market disparities among low- and high-skilled migrants. Our results support the view that agglomeration economies......We analyze the determinants and regional implications of internal migration flows across Danish municipalities in 2006–2012. Besides assessing the role of labor market and housing market factors in driving a region’s net migration rate, we particularly focus on agglomeration factors identified...... by “new” migration theories related to regional growth models and the new economic geography. The work contributes to the field in the following way: we extend the scarce literature on the different channels through which agglomeration economies act as an attractor for mobile labor. Moreover, we account...

  10. Impact of European Legislation in Migration Flows across EU borders

    OpenAIRE

    Mikes, Antonin Bernard Thompson

    2008-01-01

    This work outlines issues related to migratory policy in the European Union. The aim o f the work is to determine whether or not the European Union has been successful in reducing the push factors that lead to migratory flows. This work outline the historical situation o f migration in Europe from early post war migrations o f guest workers to the imposition o f restrictive policies intended to reduce migratory flows. General theories related to migration are discussed as are some o f the pro...

  11. Balancing the act: The international migration of medical graduates.

    Science.gov (United States)

    Zubaran, Carlos

    2011-03-01

    In this article I examine the phenomenon of international migration of medical graduates. The debate involving the ethical aspects of medical migration as well as the obstacles faced by doctors to practice unreservedly in their host countries are addressed. The situation of Australia in this context is also scrutinised. Finally, I propose a series of strategies aimed at minimising the unfavourable consequences of the international migration of doctors. This commentary favours a reform in the way institutions and society respond to the process of medical migration and to the needs of migrant doctors. Continued research on this health care topic is required in order to identify the major factors that play a role in this process.

  12. In Search of Peace: Structural Adjustment, Violence, and International Migration.

    Science.gov (United States)

    Alvarado, Steven Elías; Massey, Douglas S

    2010-07-01

    The authors analyze the effects of structural adjustment and violence on international migration from selected countries in Latin America by estimating a series of event history models that predicted the likelihood of initial migration to the United States as a function of the murder rate, economic openness, and selected controls in the country of origin. Although several theories posit a connection between structural economic change and violence, such a pattern held only in Nicaragua, where the homicide rate increased as the economy was opened to trade and average incomes deteriorated. Moreover, only in Nicaragua was lethal violence positively related to out-migration. In Mexico, Costa Rica, and Guatemala, rising violence reduced the likelihood of emigration. Violence does not appear to have uniform effects on patterns of international migration but depends on broader social and political conditions within particular countries.

  13. Seamless Flow Migration on Smartphones without Network Support

    CERN Document Server

    Rahmati, Ahmad; Tossell, Chad; Nicoara, Angela; Zhong, Lin; Kortum, Phil; Singh, Jatinder

    2010-01-01

    This paper addresses the following question: Is it possible to migrate TCP/IP flows between different networks on modern mobile devices, without infrastructure support or protocol changes? To answer this question, we make three research contributions. (i) We report a comprehensive characterization of IP traffic on smartphones using traces collected from 27 iPhone 3GS users for three months. (ii) Driven by the findings from the characterization, we devise two novel system mechanisms for mobile devices to sup-port seamless flow migration without network support, and extensively evaluate their effectiveness using our field collected traces of real-life usage. Wait-n-Migrate leverages the fact that most flows are short lived. It establishes new flows on newly available networks but allows pre-existing flows on the old network to terminate naturally, effectively decreasing, or even eliminating, connectivity gaps during network switches. Resumption Agent takes advantage of the functionality integrated into many mod...

  14. Migration Flows from the Perspective of Sending and Receiving Countries

    DEFF Research Database (Denmark)

    Pytlikova, Mariola

    , the former communist countries have become a relatively new and large source of immigration. In my PhD thesis I analyze the recent developments in international migration by using a rich dataset, which I collected myself by contacting national statistical offices. I use state-of-art econometric tools in my...... by and the migration propensity decreases with the distance between two districts. Overall, the scale of interregional migration in the Czech Republic is very low given the large interregional disparities, indicating relatively low migration propensity of Czechs. But the behavior is driven strongly by wages. While......-based selectivity effects" in international migration. We test whether immigrants from low-income countries, where the educational level is relatively low, tend to go to countries with higher welfare and lower income inequality and whether immigrants from high-income countries tend to go to countries with a lower...

  15. Internal Migration, Regional Labour Market Dynamics and Implications for German East-West Disparities – Results from a Panel VAR

    DEFF Research Database (Denmark)

    Alecke, Björn; Mitze, Timo; Untiedt, Gerhard

    This paper analyses the causal linkages between regional labour market variables and internal migration flows among German states between 1991–2006. We adopt a Panel VAR approach to identify the feedback effects among the variables and analyse the dynamic properties of the system through...... impulseresponse functions.We also use the model to track the evolution of the particular East-West migration since re-unification aiming to shed more light on the East German “empirical puzzle”, characterized by lower migration responses than expected from the regional labour market position relative to the West......, this supports the view of “repressed” migration flows for that period....

  16. International Migration and Development: A review in light of the crisis

    OpenAIRE

    2011-01-01

    Increasing international migratory flows in the last four decades is one of the most visible manifestations of the globalization process. In spite of its potential positive effect on global efficiency and well-being, little progress has been made in designing and promoting a normative and institutional framework to allow a better global governance of international migration. The current crisis has added new concerns in relation to migrant situation particularly in the countries more affected ...

  17. The international migration of dentists: directions for research and policy.

    Science.gov (United States)

    Balasubramanian, Madhan; Brennan, David Simon; Spencer, A John; Short, Stephanie Doris

    2016-08-01

    In 2010, the World Health Organization Global Code of Practice for International Recruitment of Health Personnel (the WHO Code) was adopted by the 193 Member States of the WHO. The WHO Code is a tool for global diplomacy, providing a policy framework to address the challenges involved in managing dentist migration, as well as improving the retention of dental personnel in source countries. The WHO Code recognizes the importance of migrant dentist data to support migration polices; minimum data on the inflows, outflows and stock of dentists are vital. Data on reasons for dentist migration, job satisfaction, cultural adaptation issues, geographic distribution and practice patterns in the destination country are important for any policy analysis on dentist migration. Key challenges in the implementation of the WHO Code include the necessity to coordinate with multiple stakeholders and the lack of integrated data on dentist migration and the lack of shared understanding of the interrelatedness of workforce migration, needs and planning. The profession of dentistry also requires coordination with a number of private and nongovernmental organizations. Many migrant dentist source countries, in African and the South-Asian WHO Regions, are in the early stages of building capacity in dentist migration data collection and research systems. Due to these shortcomings, it is prudent that developed countries take the initiative to pursue further research into the migration issue and respond to this global challenge.

  18. Migrant networks and international migration: testing weak ties.

    Science.gov (United States)

    Liu, Mao-Mei

    2013-08-01

    This article examines the role of migrant social networks in international migration and extends prior research by testing the strength of tie theory, decomposing networks by sources and resources, and disentangling network effects from complementary explanations. Nearly all previous empirical research has ignored friendship ties and has largely neglected extended-family ties. Using longitudinal data from the Migration between Africa and Europe project collected in Africa (Senegal) and Europe (France, Italy, and Spain), this article tests the robustness of network theory-and in particular, the role of weak ties-on first-time migration between Senegal and Europe. Discrete-time hazard model results confirm that weak ties are important and that network influences appear to be gendered, but they do not uphold the contention in previous literature that strong ties are more important than weak ties for male and female migration. Indeed, weak ties play an especially important role in male migration. In terms of network resources, having more resources as a result of strong ties appears to dampen overall migration, while having more resources as a result of weaker ties appears to stimulate male migration. Finally, the diversity of resources has varied effects for male and female migration.

  19. Modern Gravity Models of Internal Migration. The Case of Romania

    Directory of Open Access Journals (Sweden)

    Daniela BUNEA

    2012-04-01

    Full Text Available Internal migration, although less investigated than international migration, is a key mechanism for adjustment to regional economic shocks, especially when other tools prove useless. But this process has very complex factors of determination which can be economic, social, demographic, environmental, etc. Based on previous international studies, in the case of Romania the robust variables proved to be the population size, the per capita gross domestic product, the road density, an amenity index and the crime rate from a static perspective, and the previous migration, the population size and the amenity index from a dynamic perspective. The techniques I have employed in making this study are the Least Square Dummy Variables (LSDV, or the fixed effects method and the Generalized Method of Moments (GMM, or the dynamic method both applied to panel data.

  20. Measuring perinatal health equity and migration indicators for international comparisons.

    Science.gov (United States)

    Gagnon, Anita J; Small, Rhonda; Sarasua, Irene; Lang, Carly

    2015-01-01

    An international research collaboration answered, "Can equity in perinatal health for migrant women be measured for comparison across countries?" In nine countries, perinatal databases were assessed for the availability of equity indicators. Equity data were also sought from women and health records. Optimal sources of data differed depending on the migrant perinatal health equity indicator. Health and migration data, required to capture equity, were often not reported in the same location. Migration indicators other than country of birth were underreported. Perinatal health equity can be measured for international comparisons, although a standardized protocol is required to capture all indicators.

  1. Post-War Migration Flows and Disparities in Mortality from Age 50 Years Onwards

    DEFF Research Database (Denmark)

    Zarulli, Virginia

    2016-01-01

    Compositional changes due to internal migration can modify the distribution of health outcomes, death rates, and socio-economic characteristics of a specific geographical area. Migration flows may affect patterns of socio-economic inequalities in mortality as well. However, despite...... these inequalities being an important social and geopolitical feature of an area, there is still little empirical evidence on this effect. This paper contributes to deepening the knowledge about this phenomenon by investigating whether post-war internal migration in Italy affected the pattern of mortality inequality...... by socio-economic status, from age 50 years onwards, in Turin, one of the main industrial areas of the country, to which many low-educated individuals from the southern regions migrated, seeking jobs in the car factories. Migrants might be selected in terms of robustness because of the healthy migrant...

  2. International immigration, internal migration, and homicide in Canadian provinces.

    Science.gov (United States)

    Andresen, Martin A

    2013-05-01

    The relationship between immigration and crime is politically charged and often fueled by the presence (or lack) of xenophobia. Many theoretical and empirical assessments of this relationship indicate that immigration does indeed lead to increased crime, but more recent (and very early) research investigating homicide calls this finding into question. The current analysis investigates the relationship between immigration and homicide using multiple measures of migration and Canadian provinces as the unit of analysis. It is found that the link between immigration and homicide is complex and dependent on the measure of migration used. Generally speaking, the results presented here are consistent with the more recent and very early research. Immigration, in and of itself, does not increase homicide. Rather it is the increase in the most criminogenic subpopulation that matters, that is young males.

  3. Population perspectives on the causes of international migration.

    Science.gov (United States)

    Stahl, C

    1987-06-01

    The paper considers the causes of international voluntary labor migration from the economic perspective of supply of and demand for labor force. Changing global economic forces figure in the relevant decisions of individuals, industries, and countries. The author 1st examines global economic forces responsible for creating an unlimited supply of migrant labor within the 3rd world ready to work abroad. Reasons why a marked proportion of international labor migration is sourced in a limited number of countries are then discussed, followed by consideration of selectivity factors for laborers coming from certain subpopulations within given countries. Economic forces supporting demand for labor in countries of immigration are then discussed, with attention to the limits of growth in demand. The author concludes that immigration policies of comparatively wealthy countries determine the magnitude of international labor migration. These policies, however, are developed on the basis of perceived labor needs of the country, and are subject to become more restrictive as foreign workers increasingly impose upon the cultural space of the indigenous population. Restricting further immigration to workers only, not their dependents, is not encouraged as viable policy. Further discussion is included on increasing international economic inequalities resulting from international labor migration, and the role of source countries in ensuring the provision of suitable working conditions for immigrant workers.

  4. Identity Change in the World of International Migration

    Directory of Open Access Journals (Sweden)

    Carmen Cornelia BALAN

    2015-12-01

    Full Text Available In this new publication, Cristina Cormoş professionally addresses a sensitive issue, complex and difficult in the same time, and ambitiously manages to give us a picture of international migration viewed through identity change. Starting from the hypothesis that "migration is a change that simultaneously occurs in both physical and socio-cultural realms, which implies not only movement from one community to another, but also the disintegration of structural bonds in the departure area, paralleled by a cultural assimilation of the destination environment", the author analyzes identity changes of the emigrants throughout the entire migration process, the factors underlying these changes, as well as the consequences and implications of these factors in the return migration. The issues addressed within this book also cover the changes occurred in the family and community of origin as a result of the absence of one of its members and of the manifestation of identity changes respectively.

  5. A preliminary study of international migration of the Chinese people.

    Science.gov (United States)

    Zhu, G

    1994-01-01

    International Chinese migration has spanned five periods: 1) an initial period of random and short-term migration dating back to the Qing and Han dynasties; 2) a spontaneous period since the Sui and Tang dynasties along trade routes; 3) a transition period during the Ming dynasty and the early Qing dynasty with war, poverty, and population growth as push factors; 4) peak migration during the Opium War period due to economic depression, population pressure, and the "coolie" trade; and 5) continuous development between the 1920s and 1949. Migration tended to occur between Guangdong and Fujian provinces and other southeast Asian countries. Four factors were identified as necessary for international migration to occur: the origin of migration, the destination factor, the middle link factor, and the immigrant characteristics. The origins of early Chinese migration appeared in a country of political corruption, population pressure, a backward economy, and social chaos. The pull factors at destination end were demand for labor. The middle link was the short distance between Guangdong and Fujian provinces and southeast Asian countries and longstanding nongovernmental exchanges. Other links were the similarity of climate, similar racial features, cultural lifestyle similarities, and convenient transportation. The people in these two provinces had a history of migration and a personality suitable for the spirit of adventure. Peak migration occurred during the late Qing dynasty and during the continuous development period. Between 1840 and 1911 there were about 10 million Chinese immigrants and during 1911 and 1949 there were about 6 million. In general, over 20 million immigrated prior to 1949, of which about 50% migrated during the peak period, 33% during the continuous period, and 20% before 1840. This amounted to about 33% of European migration and two times African migration. 60% were from Guangdong, and 30% were from Fujian province, of whom most were from counties

  6. Common and Specific Features of Migration Flows In Russia, CIS and Far Abroad

    Directory of Open Access Journals (Sweden)

    Tamara Vladimirovna Kuprina

    2015-06-01

    Full Text Available The article discusses the features of migration flows in Russia, CIS and abroad in terms of transnationality and translocality. Special attention is paid to migration flows from Asia, depending on the gender perception. During the analysis, the preferences of migrants of different age groups are determined. It shows their desire for a more independent financial and professional life, relationship with family responsibilities, plans for the future. The data obtained by the method of continuous selection have led to the following conclusions: migration is a multidimensional phenomenon that requires multidisciplinary research; the heterogeneity of migration flows to the socio-cultural and gender features must be taken into account; the problem of illegal migration requires special solutions; in connection with the emigration of highly skilled professionals and immigration of low-skilled personnel, a professional important indicator of migratory replacement and attracting compatriots from abroad are important. The data obtained can be used for ethnic and cultural planning in order to improve production activities that affect the quality of solving of production tasks and programming adaptation of migrants as the significant impact of intangible factors on the development of society has been noted by economists for a long time. Thus, the economic sustainability requires new thinking based on socio-cultural sustainability determined by such global phenomena as international migration flows.

  7. The workforce for health in a globalized context--global shortages and international migration.

    Science.gov (United States)

    Aluttis, Christoph; Bishaw, Tewabech; Frank, Martina W

    2014-01-01

    The 'crisis in human resources' in the health sector has been described as one of the most pressing global health issues of our time. The World Health Organization (WHO) estimates that the world faces a global shortage of almost 4.3 million doctors, midwives, nurses, and other healthcare professionals. A global undersupply of these threatens the quality and sustainability of health systems worldwide. This undersupply is concurrent with globalization and the resulting liberalization of markets, which allow health workers to offer their services in countries other than those of their origin. The opportunities of health workers to seek employment abroad has led to a complex migration pattern, characterized by a flow of health professionals from low- to high-income countries. This global migration pattern has sparked a broad international debate about the consequences for health systems worldwide, including questions about sustainability, justice, and global social accountabilities. This article provides a review of this phenomenon and gives an overview of the current scope of health workforce migration patterns. It further focuses on the scientific discourse regarding health workforce migration and its effects on both high- and low-income countries in an interdependent world. The article also reviews the internal and external factors that fuel health worker migration and illustrates how health workforce migration is a classic global health issue of our time. Accordingly, it elaborates on the international community's approach to solving the workforce crisis, focusing in particular on the WHO Code of Practice, established in 2010.

  8. Network Dependency in Migration Flows – A Space-time Analysis for Germany since Re-unification

    DEFF Research Database (Denmark)

    Mitze, Timo

    The contribution of this paper is to analyse the role of network interdependencies in a dynamic panel data model for German internal migration fl ows since re-unification. So far, a capacious account of spatial patterns in German migration data is still missing in the empirical literature....... In the context of this paper, network dependencies are associated with correlations of migration flows strictly attributable to proximate flows in geographic space. Using the neoclassical migration model, we start from its aspatial specification and show by means of residual testing that network dependency eff...

  9. Network Dependency in Migration Flows – A Space-time Analysis for Germany since Re-unification

    DEFF Research Database (Denmark)

    Mitze, Timo

    . In the context of this paper, network dependencies are associated with correlations of migration flows strictly attributable to proximate flows in geographic space. Using the neoclassical migration model, we start from its aspatial specification and show by means of residual testing that network dependency eff...... equation and at the same time qualify the model to pass essential IV diagnostic tests. The basic message for future research is that space-time dynamics is highly relevant for modelling German internal migration flows.......The contribution of this paper is to analyse the role of network interdependencies in a dynamic panel data model for German internal migration fl ows since re-unification. So far, a capacious account of spatial patterns in German migration data is still missing in the empirical literature...

  10. Concepts, definitions and classifications for internal migration statistics in Africa.

    Science.gov (United States)

    1983-01-01

    This brief discussion of the various data collection systems used in Africa represents the data situation with regard to African migration statistics. Population censuses are increasingly becoming the most popular source for migration statistics in Africa. The derivation of internal migration information from surrogate measures such as age and sex distributions is predicated on the assumption that the movement is selective with respect to these variables. The part attributable to migration after taking into account natural increases is made difficult in Africa because the correct levels of birth and death rates are not usually known with certainty, nationally or locally. The population census data are useful for the investigation of the national volumes and rates of migration; this provides information on broad patterns of migration for countries. However, it is not suitable for migration studies that intend to investigate in-depth such topics as determinants and impact and delineate various types of migratory movements. African countries should, in addition to the birthplace question, include at least 1 of the following supplementary questions: 1) duration of residence, 2) place of previous residence, and 3) place of residence at a fixed prior date. It is increasingly noted that sample surveys are where most of the new data required for policy ought to come from. Longitudinal surveys on migration are also required to advance our present knowledge about the various types of mobility and their seasonal character and about the consequences of the movement. Data collection systems must also be improved in the concepts, definitions, and classifications. This applies to the definition of migration as well as the spatial classifications used as the reference units for the collection of data and the definitions of rural and urban.

  11. International Student Migration and Social Stratification in China

    Science.gov (United States)

    Xiang, Biao; Shen, Wei

    2009-01-01

    During the late 1990s China moved from a period of "wealth creation" that benefited the majority of the population to a period of "wealth concentration" that benefited a minority. This essay focuses on the role of international student migration from China to other countries in this process. In particular the authors delineate…

  12. Internal migration and household living conditions in Ethiopia

    Directory of Open Access Journals (Sweden)

    Blessing Uchenna Mberu

    2006-06-01

    Full Text Available Using the 1998 Migration, Gender and Health Survey in Five Regions of Ethiopia, and multivariate regression techniques, this paper examines the relationship between internal migration and household living conditions. The analysis finds significant living condition advantage of permanent and temporary migrants over non-migrants. These advantages are primarily linked to migration selectivity by education and non-agricultural income. Once the independent effects of these variables are controlled, no statistical significant independent association exists between migration status and living conditions. Government policies of resettlement in the 1980s and ethnic federalism of the 1990s may have engendered stress migration and exacerbated poor living outcomes for return migrants. The resort to migration and/or resettlement as an individual or government policy response to periodic unfavorable conditions in places of origin is not strongly supported by this analysis as the key to improved living conditions. Promoting higher education and opportunities for employment outside the agricultural sector are more likely to yield improved living conditions in Ethiopia.

  13. MODELING HEADCUT DEVELOPMENT AND MIGRATION IN UPLAND CONCENTRATED FLOWS

    Institute of Scientific and Technical Information of China (English)

    Sean J. BENNETT; Carlos V. ALONSO

    2005-01-01

    On hillslopes and agricultural fields, discrete areas of intense, localized soil erosion commonly take place in the form of migrating headcuts. These erosional features significantly increase soil loss and landscape degradation, yet the unsteady, transient, and migratory habits of headcuts complicate their phenomenological and erosional characterization. Here a unique experimental facility was constructed to examine actively migrating headcuts typical of upland concentrated flows. Essential components of the facility include a deep soil cavity with external drainage, rainfall simulator, capacity for overland flow, and a video recording technique for data collection. Results from these experiments show that:(1) after a short period of adjustment, headcut migration attained a steady-state condition, where the rate of migration, scour hole geometry, and sediment discharge remain constant with time; (2)boundary conditions of higher rates of overland flow, steeper bed slopes, and larger initial headcut heights produced systematically larger scour holes with higher rates of soil erosion; and (3) during migration, the turbulent flow structure within the scour hole remained unchanged, consisting of an overfall nappe at the brink transitioning into a reattached wall jet with two recirculation eddies within the plunge pool. The systematic behavior of headcut development and migration enabled the application of modified jet impingement theory to predict with good success the characteristics of the impinging jet, the depth of maximum scour, the rate of headcut migration, and the rate of sediment erosion. These laboratory data and the analytical formulation can be used in conjunction with soil erosion prediction technology to improve the management of agricultural areas impacted by headcut development and ephemeral gully erosion.

  14. Lateral migration of a capsule in a parabolic flow.

    Science.gov (United States)

    Nix, S; Imai, Y; Ishikawa, T

    2016-07-26

    Red blood cells migrate to the center of the blood vessel in a process called axial migration, while other blood cells, such as white blood cells and platelets, are disproportionately found near the blood vessel wall. However, much is still unknown concerning the lateral migration of cells in the blood; the specific effect of hydrodynamic factors such as a wall or a shear gradient is still unclear. In this study, we investigate the lateral migration of a capsule using the boundary integral method, in order to compute exactly an infinite computational domain for an unbounded parabolic flow and a semi-infinite computational domain for a near-wall parabolic flow in the limit of Stokes flow. We show that the capsule lift velocity in an unbounded parabolic flow is linear with respect to the shear gradient, while the lift velocity in a near-wall parabolic flow is dependent on the distance to the wall. Then, using these relations, we give an estimation of the relative effect of the shear gradient as a function of channel width and distance between the capsule and the wall. This estimation can be used to determine cases in which the effect of the shear gradient or wall can be neglected; for example, the formation of the cell-free layer in blood vessels is determined to be unaffected by the magnitude of the shear gradient. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Global migration of internationally educated nurses: Experiences of employment discrimination

    Directory of Open Access Journals (Sweden)

    Salimah R. Walani

    2015-01-01

    Discrimination and unequal treatment faced by migrant nurses is one of the most important issues related to international migration of nurses. This article present a discussion of the broad topics surrounding nurse migration followed by a synthesis of 15 published qualitative and quantitative research articles related to specifically to the subject of employment discrimination experiences of internationally educated nurses in Canada, United Kingdom and the United States. Evidence shows that international nurses often encounter covert and overt discrimination in the workplace. It is important for nurses to be aware of the extent and nature of employment discrimination encountered by migrant nurses. Nursing leaders and policy makers need to ensure that all nurses are treated equally in the workplace.

  16. South-North migration policies. Recent international achievements.

    Science.gov (United States)

    Camilleri, R

    1997-06-01

    "This article aims at assessing migration policies pursued recently by countries surrounding the Mediterranean basin and other European states as they affect and influence South to North migratory movements. It concentrates on South/North migration, limiting the discussion mainly to the Maghreb group of countries. Without disregarding or in any way minimising the intensity of existing problems whose solution may not be in sight, the intention is to trace the positive developments in the debate on such issues through the individual and collective efforts of scholars, planners, politicians, governmental and non-governmental organisations, the Churches, and international organisations." (EXCERPT)

  17. European Integration, Labour Market Dynamics and Migration Flows

    Directory of Open Access Journals (Sweden)

    Martinoia, Michela

    2011-06-01

    Full Text Available The paper has two objectives. Firstly, we wish to evaluate whether a greater economic integration has effects, and of what type, on migration flows from Central and Eastern Europe (New Member States of the EU, NMS towards the fifteen countries of the European Union (EU-15. Secondly, we wish to understand what effect the migration flows from the NMS have on the labour market of the receiving countries in the EU-15. The most suitable theoretical context that seems to summarise European labour market characteristics is that of the insider/outsider model by Layard, Nickell and Jackman (Layard et al., 1991. We have modified the above mentioned model by introducing two innovations. Firstly, we constructed three measures that act as a proxy for economic integration: the Intra Regional Trade Index (IRTI, Global Trade Index (GTI and Financial Market Integration (FMI. Then we placed the three indicators into the insider/outsider model to arrive at a modified version of Layard, Nickell and Jackman (Layard et al., 1991. The second innovative contribution was the introduction of an equation modelling migration flows. The creation of this equation is inspired by the neo-classical approach to migration theory (Harris-Todaro, 1970. The theoretical model, based on rational expectations, has been solved to find the equilibrium solution and the impact multipliers. We then carried out an empirical analysis, which involved estimating a Structural Vector Autoregression Model (SVAR. The aim of this estimation was to evaluate, on the one hand, the effect that greater European integration (a positive shock to the integration indicators has on migration flows, and, on the other, to measure the type of effect that migration flows could have on the labour market of the EU-15 countries, considered as a single entity. The results of our empirical evidence show that economic integration does generate significant effects on migration flows from the enlargement countries

  18. International migration and the propagation of HIV in sub-Saharan Africa.

    Science.gov (United States)

    Docquier, F; Vasilakis, Ch; Tamfutu Munsi, D

    2014-05-01

    In this paper, we identify and quantify the role of international migration in the propagation of HIV across sub-Saharan African countries. We use panel data on bilateral migration flows and HIV prevalence rates covering 44 countries after 1990. Controlling for unobserved heterogeneity, reverse causality, reflection issues, incorrect treatment of country fixed effects and spatial autocorrelation, we find evidence of a highly robust emigration-induced propagation mechanism. On the contrary, immigration has no significant effect. Numerical experiments reveal that the long-run effect of emigration accounts for more than 4 percent of the number of HIV cases in 15 countries (and more than 20 percent in 6 countries).

  19. [Internal and middle-distance migration in Italy, 1500-1900].

    Science.gov (United States)

    Corsini, C A

    1993-01-01

    This is a general review of trends in migration in Italy from 1500 to 1900. The author examines questions concerning the definition of migration, problems with data sources, the characteristics of internal migration, and the factors influencing emigration.

  20. Suspension flow modelling in particle migration and microfiltration

    NARCIS (Netherlands)

    Vollebregt, H.M.; Sman, van der R.G.M.; Boom, R.M.

    2010-01-01

    We review existing mixture models for shear-induced migration (SIM) in flowing viscous, concentrated particle suspensions via an analysis of the models from the perspective of a two-fluid formulation. Our analysis shows that particle suspensions in strong non-linear shear fields are a prime example

  1. Social Capital and International Migration from Latin America

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    Douglas S. Massey

    2011-01-01

    Full Text Available We combine data from the Latin American Migration Project and the Mexican Migration Project to estimate models predicting the likelihood of taking of first and later trips to the United States from five nations: Mexico, the Dominican Republic, Costa Rica, Nicaragua, and Peru. The models test specific hypotheses about the effects of social capital on international migration and how these effects vary with respect to contextual factors. Our findings confirm the ubiquity of migrant networks and the universality of social capital effects throughout Latin America. They also reveal how the sizes of these effects are not uniform across settings. Social capital operates more powerfully on first as opposed to later trips and interacts with the cost of migration. In addition, effects are somewhat different when considering individual social capital (measuring strong ties and community social capital (measuring weak ties. On first trips, the effect of strong ties in promoting migration increases with distance whereas the effect of weak ties decreases with distance. On later trips, the direction of effects for both individual and community social capital is negative for long distances but positive for short distances.

  2. Social Capital and International Migration from Latin America.

    Science.gov (United States)

    Massey, Douglas S; Aysa-Lastra, María

    2011-01-01

    We combine data from the Latin American Migration Project and the Mexican Migration Project to estimate models predicting the likelihood of taking of first and later trips to the United States from five nations: Mexico, the Dominican Republic, Costa Rica, Nicaragua, and Peru. The models test specific hypotheses about the effects of social capital on international migration and how these effects vary with respect to contextual factors. Our findings confirm the ubiquity of migrant networks and the universality of social capital effects throughout Latin America. They also reveal how the sizes of these effects are not uniform across settings. Social capital operates more powerfully on first as opposed to later trips and interacts with the cost of migration. In addition, effects are somewhat different when considering individual social capital (measuring strong ties) and community social capital (measuring weak ties). On first trips, the effect of strong ties in promoting migration increases with distance whereas the effect of weak ties decreases with distance. On later trips, the direction of effects for both individual and community social capital is negative for long distances but positive for short distances.

  3. The health impacts of international migration on Mexican women.

    Science.gov (United States)

    Ullmann, S Heidi

    2012-01-01

    Mexican migration to the USA is a phenomenon that affects a significant number of Mexican households. In the area of health, considerable research has been devoted to international migrants, but less is known about the health impacts of migration on other household members, particularly the wives of migrants. I used data from the Mexican Migration Project to investigate the health impacts of having a migrant husband. As part of my analysis I explored the relationship between the husbands' migration and several health conditions and behaviours among the wives. In contrast to existing research on the subject, I also considered whether the amount of time the husband spent in the US mediates the relationship between migration and health. Finally, I addressed the possibility that the wives of migrants differ in their initial health endowments from the wives of non-migrants. I found that despite having similar initial health endowments, the wives of migrants have poorer mental health, a higher prevalence of heart disease, and they are more likely to be obese or overweight than the wives of non-migrants.

  4. Port catheter fracture and migration in Internal Jugular Vein.

    Science.gov (United States)

    Doley, Rudra Prasad; Brar, Preetinder; Chaudhary, Sanchit; Bedi, Rajeev; Swami, Adarsh Chander; Wig, Jai Dev

    2012-01-01

    Central venous access devices for chemotherapy are being used extensively in patients with cancer. Spontaneous fracture and migration of the catheter is uncommon. We present the uncommon occurrence of a fracture and spontaneous migration of the fragment into the internal jugular vein as a delayed complication of a central venous access catheter implanted for chemotherapy administration. A patient with Ewing's sarcoma of the humerus with metastasis in the lungs underwent placement of a totally implantable venous access device. The port was in place for 1 year. The patient presented with pain in the right side of the neck. A chest X-ray demonstrated complete transection of the catheter and migration of the catheter fragment in the internal jugular vein. Both the migrated catheter fragment and the proximal part of the catheter were retrieved surgically. He had an uneventful recovery. Catheter fracture remains a potential complication, which must be recognized and treated promptly. Periodic chest imaging is recommended for detection and timely removal of the catheter.

  5. IJEPA: Gray Area for Health Policy and International Nurse Migration.

    Science.gov (United States)

    Efendi, Ferry; Mackey, Timothy Ken; Huang, Mei-Chih; Chen, Ching-Min

    2017-05-01

    Indonesia is recognized as a nurse exporting country, with policies that encourage nursing professionals to emigrate abroad. This includes the country's adoption of international principles attempting to protect Indonesian nurses that emigrate as well as the country's own participation in a bilateral trade and investment agreement, known as the Indonesia-Japan Economic Partnership Agreement that facilitates Indonesian nurse migration to Japan. Despite the potential trade and employment benefits from sending nurses abroad under the Indonesia-Japan Economic Partnership Agreement, Indonesia itself is suffering from a crisis in nursing capacity and ensuring adequate healthcare access for its own populations. This represents a distinct challenge for Indonesia in appropriately balancing domestic health workforce needs, employment, and training opportunities for Indonesian nurses, and the need to acknowledge the rights of nurses to freely migrate abroad. Hence, this article reviews the complex operational and ethical issues associated with Indonesian health worker migration under the Indonesia-Japan Economic Partnership Agreement. It also introduces a policy proposal to improve performance of the Indonesia-Japan Economic Partnership Agreement and better align it with international principles focused on equitable health worker migration.

  6. Forced migration and mental health: prolonged internal displacement, return migration and resilience.

    Science.gov (United States)

    Siriwardhana, Chesmal; Stewart, Robert

    2013-03-01

    Forced internal displacement has been rising steadily, mainly due to conflict. Many internally displaced people (IDP) experience prolonged displacement. Global research evidence suggests that many of these IDP are at high risk for developing mental disorders, adding weight to the global burden of disease. However, individual and community resilience may act as protective factors. Return migration may be an option for some IDP populations, especially when conflicts end, although return migration may itself be associated with worse mental health. Limited evidence is available on effects of resettlement or return migration following prolonged forced internal displacement on mental health. Also, the role of resilience factors remains to be clarified following situations of prolonged displacement. The public health impact of internal displacement is not clearly understood. Epidemiological and interventional research in IDP mental health needs to look beyond medicalised models and encompass broader social and cultural aspects. The resilience factor should be integrated and explored more in mental health research among IDP and a clearly focused multidisciplinary approach is advocated.

  7. International flow of Zambian nurses

    Directory of Open Access Journals (Sweden)

    McPake Barbara

    2009-11-01

    Full Text Available Abstract This commentary paper highlights changing patterns of outward migration of Zambian nurses. The aim is to discuss these pattern changes in the light of policy developments in Zambia and in receiving countries. Prior to 2000, South Africa was the most important destination for Zambian registered nurses. In 2000, new destination countries, such as the United Kingdom, became available, resulting in a substantial increase in migration from Zambia. This is attributable to the policy of active recruitment by the United Kingdom's National Health Service and Zambia's policy of offering Voluntary Separation Packages: early retirement lump-sum payments promoted by the government, which nurses used towards migration costs. The dramatic decline in migration to the United Kingdom since 2004 is likely to be due to increased difficulties in obtaining United Kingdom registration and work permits. Despite smaller numbers, enrolled nurses are also leaving Zambia for other destination countries, a significant new development. This paper stresses the need for nurse managers and policy-makers to pay more attention to these wider nurse migration trends in Zambia, and argues that the focus of any migration strategy should be on how to retain a motivated workforce through improving working conditions and policy initiatives to encourage nurses to stay within the public sector.

  8. China’s Internal Migration, Public Policies, and Economic Growth

    Science.gov (United States)

    2012-12-01

    the 40 Ibid. 41 Justin Yifu Lin, The China Miracle (Hong Kong: The Chinese University of Hong Kong...Chinese Economy Transitions and Growth, 69. 77 Dorothy J. Solinger, Contesting Citizenship in Urban, 41. 78 Justin Yifu Lin, The China Miracle, 69...76 Liang, Zai, and Michael J. White. “Internal Migration in China, 1950–1988.” Demography 33, no. 3 (August 1996): 375–384. Lin, Justin

  9. Particle migration in two-phase, viscoelastic flows

    Science.gov (United States)

    Jaensson, Nick; Hulsen, Martien; Anderson, Patrick

    2014-11-01

    Particles suspended in creeping, viscoelastic flows can migrate across stream lines due to gradients in normal stresses. This phenomenon has been investigated both numerically and experimentally. However, particle migration in the presence of fluid-fluid interfaces is hardly studied. We present results of simulations in 2D and 3D of rigid spherical particles in two-phase flows, where either one or both of the fluids are viscoelastic. The fluid-fluid interface is assumed to be diffuse and is described using Cahn-Hilliard theory. The particle boundary is assumed to be sharp and is described by a boundary-fitted, moving mesh. The governing equations are solved using the finite element method. We show that differences in normal stresses between the two fluids can induce a migration of the particle towards the interface in a shear flow. Depending on the magnitude of the surface tension and the properties of the fluids, particle migration can be halted due to the induced Laplace pressure, the particle can be adsorbed at the interface, or the particle can cross the interface into the other fluid. Dutch Polymer Institute (DPI), P.O. Box 902, 5600 AX Eindhoven, The Netherlands.

  10. MIGRATE: A FOSS WEB MAPPING APPLICATION FOR EDUCATING AND RAISING AWARENESS ABOUT MIGRATION FLOWS IN EUROPE

    Directory of Open Access Journals (Sweden)

    M. A. Brovelli

    2017-07-01

    Full Text Available Recent years have seen a noticeable growth in migration flows from Africa and Middle East to Southern Europe, thus generating a remarkable increase of attention on media and public opinion, sometimes resulting in stereotypes and prejudices. Funded by the European Commission – Joint Research Centre through the MYGEOSS program, MIGRation pATtterns in Europe (MIGRATE aims at educating the citizens about migration fluxes in Europe using a gamification approach based on a trivia game. MIGRATE is completely developed with Free and Open Source Software. On the server-side Django is used to define the models that handle all the required data and tables are created in a PostgreSQL database. Questions and answers are sent in JSON format to the client, while the geospatial layers in GeoJSON format are rendered on the map interface using OpenLayers 3. Bootstrap, HTML5 and CSS3 are used for responsive design, while the jQuery library is used to ease the JavaScript programming. All the data sources used within MIGRATE are available as full and open access with no restrictions for reuse, except for the obligation to mention the source of the input data. Exploited data sources include OpenStreetMap for geospatial information, and UNHCR, IOM, Eurostat and The Migrant’s Files project for non-geospatial information. Overall, data shows how the users’ perceptions change while playing and that players’ awareness of migration-related problems increases with the number of games played. The source code of MIGRATE and the collected data are available respectively under the EU Public License (EUPL and the CC BY 4.0 license.

  11. Management of migration flows in the European Union

    Directory of Open Access Journals (Sweden)

    Dana Larisa Drugă

    2011-12-01

    Full Text Available International migration can contribute to the economic growth of the European Union (EU as a whole, as well as provide resources for migrants and their home countries, and thus contribute to their development. It can be an opportunity, because it is a factor of human and economic exchange and enables people to achieve what they aspire to. However, there is a need to manage migration in a manner that takes account of Europe's reception capacity in terms of its labour market, housing and health, education and social services, while protecting migrants against possible exploitation by criminal networks.

  12. Height convergence and internal migration in mid-twentieth-century Italy.

    Science.gov (United States)

    Lanari, Donatella; Bussini, Odoardo

    2014-01-01

    Height convergence across Italian regions during the second half of the twentieth century is a widely recognized fact. However, it has been suggested that this process was partly affected by the massive migratory flow of people from southern to northern Italy in the 1950s and 1960s, which greatly slowed the height growth rate in the receiving regions, since immigrants were on average shorter than the receiving northern population. The main aims of this study were to estimate the speed of height convergence of Italian military conscripts in the second half of the twentieth century, and to estimate the contribution of internal migration from the south to the north of Italy to height convergence. We hypothesized that migrants from southern Italy reduced height levels among northerners relative to what they would have been without considering migration. We used cohort data on Italian conscripts born in 1951 and 1980. Results indicate that internal migration may explain from 24 to 32.7 percent of height convergence, meaning that ignoring migration flows yields an overestimation of the height changes for conscripts living in the south of Italy.

  13. Analysis of a South-South International Migration: Chinese Newcomers in Antananarivo and Dakar

    Directory of Open Access Journals (Sweden)

    Julien Rajaoson

    2015-07-01

    Full Text Available South-South dynamic migrations offer the opportunity to some impoverished countries to establish a Diaspora outside their territorial bases in the perspective to address the issues raised by this phenomenon of extreme poverty from abroad. First of all, it is noteworthy that the volume of South-South dynamic migrations rises to more than 61 million people, versus 62 million people in the South-North dynamic migrations. In other words, this increased propensity to mobility, which represents almost one billion people, nowadays concerns parts of the world that face extreme poverty respectively. The analysis of South-South dynamic migrations will focus our attention on one aspect of globalization that studies and expertise tend to avoid by focusing only on trading, goods and capital services. Apart from these various elements that contribute to globalization, it is necessary to include international migration to make the analysis more comprehensive. To paraphrase the words of the analyst Bruno Hérault, there is a new trend emerging in the context of the occurring exchanges between the two countries. However, according to the authors of the report posted by the UNDP in 2009, migration flows can be understood as a major vector for human development. In this regard, the report in question requires States to remove barriers in order to promote human development and allow human mobility.

  14. Coordination of contractility, adhesion and flow in migrating Physarum amoebae

    Science.gov (United States)

    Lewis, Owen L.; Zhang, Shun; Guy, Robert D.; del Álamo, Juan C.

    2015-01-01

    This work examines the relationship between spatio-temporal coordination of intracellular flow and traction stress and the speed of amoeboid locomotion of microplasmodia of Physarum polycephalum. We simultaneously perform particle image velocimetry and traction stress microscopy to measure the velocity of cytoplasmic flow and the stresses applied to the substrate by migrating Physarum microamoebae. In parallel, we develop a mathematical model of a motile cell which includes forces from the viscous cytosol, a poro-elastic, contractile cytoskeleton and adhesive interactions with the substrate. Our experiments show that flow and traction stress exhibit back-to-front-directed waves with a distinct phase difference. The model demonstrates that the direction and speed of locomotion are determined by this coordination between contraction, flow and adhesion. Using the model, we identify forms of coordination that generate model predictions consistent with experiments. We demonstrate that this coordination produces near optimal migration speed and is insensitive to heterogeneity in substrate adhesiveness. While it is generally thought that amoeboid motility is robust to changes in extracellular geometry and the nature of extracellular adhesion, our results demonstrate that coordination of adhesive forces is essential to producing robust migration. PMID:25904525

  15. Inertial Particle Migration in the Presence of a Permeate Flow

    Science.gov (United States)

    Garcia, Mike; Singelton, Amanda; Pennathur, Sumita

    2016-11-01

    Tangential Flow Filtration (TFF) is a rapid and efficient method for the filtration and separation of suspensions of particles such as viruses, bacteria or cellular material. Enhancing the efficacy of TFF not only requires a detailed understanding of particle transport mechanisms, but also the interactions between these mechanisms and a porous wall. In this work, we numerically and experimentally explore the mechanisms of inertial particle migration in the presence of a permeate flow through the porous walls of a microchannel. Numerically, we develop a force balance model to understand the competition between permeate and inertial forces and the resultant consequences on the particle equilibrium location. Experimentally, we fabricated MEMS TFF devices to study the migration of 5, 10 and 15 µm fluorescent polystyrene beads in straight channels with perpendicular permeate flow rates up to 90% of the inlet flow rate. We find that the permeate flow directly influences the inertial focusing position of the particles, both as a function of downstream channel position and ratio of inlet to outlet flow rate. Comparing experiments to our model, we can identify inertial, viscous and a co-dominant regimes.

  16. The role of language in shaping international migration

    DEFF Research Database (Denmark)

    Pytlikova, Mariola; Adsera, Alicia

    In addition to economic determinants in line with neoclassical economics and the "human capital investment" framework, a number of non-economic factors are also relevant to explain migration decisions. Beside classic factors such as "love and wars", these include random events such as environment...... and climate shocks, migrant networks, language and aspects of "cultural distance". In that regard, the more "foreign" or distant the new culture is and the larger the language barrier is, the higher are the costs of an individual to migrate to a particular destination. Fluency in destination country......'s language and/or widely spoken languages (or ease to quickly learn it) plays a key role in the transfer of human capital from the source country to another country and boosts the immigrant's success at the destination's labor market. We use data on immigration flows and stocks of foreigners in 27 OECD...

  17. The Role of Language in Shaping International Migration

    DEFF Research Database (Denmark)

    Pytlikova, Mariola; Adsera, Alicia

    In addition to economic determinants in line with neoclassical economics and the “human capital investment” framework, a number of non-economic factors are also relevant to explain migration decisions. Beside classic factors such as “love and wars”, these include random events such as environment...... and climate shocks, migrant networks, language and aspects of “cultural distance”. In that regard, the more “foreign” or distant the new culture and the larger the language barriers, the higher the costs are for an individual to migrate to a particular destination. Fluency in destination country’s language...... and/or widely spoken languages (or ease to quickly learn it) plays a key role in the transfer of human capital from the source country to another country and boosts the immigrant’s success at the destination’s labor market. We use data on immigration flows and stocks of foreigners in 27 OECD...

  18. DESCRIPTIVE ANALYSIS OF THE INTERNATIONAL MIGRATION PHENOMENON IN ROMANIA BETWEEN 1991 AND 2008

    Directory of Open Access Journals (Sweden)

    Bac Dorin Paul

    2011-07-01

    Full Text Available Migration represented and represents a very important phenomenon at global level, taking into consideration besides its demographic implications, its extremely diverse implications such as socio-economic, socio-cultural, territorial, or environmental. This represents, probably, the main reason why the research on migration is interdisciplinary, having strong connections with sociology, political sciences, history, economics, geography, demography, psychology, or low, among others. All these disciplines target different aspects of population migration, and a proper comprehension of the phenomenon implies a contribution from the part of all of them. Although migration represents a phenomenon manifested since ancient times, it has never been such an universal or significant phenomenon from the socio-economical or political perspective, as it is in present times. International migration has both a negative and positive impact on both provider and receiving countries, in general playing a very important role in the structure and dimension of the population of a country. Romania is not an exception to the previously expressed statement; furthermore, after the fall of the communist regime, migration became for Romania one of the most important socio-economical phenomena. The present paper aims at analyzing in a descriptive manner the international migration phenomenon in Romania between 1991 and 2008, from quantitative perspective. Based on data identified in the "Statistical Yearbook of Romania - 2008 and 2009 editions - the analysis revealed the fact that both immigration and emigration flows registered oscillatory evolutions in the analysed period, but the general trend of immigration was of increasing, while the one of emigration was of decreasing. Immigration was dominated by the presence of males, of persons aged between 26 and 40 and of persons coming from the Republic of Moldova. On the other side, in the case of emigration the significant

  19. Ligand migration between internal docking sites in photodissociated carbonmonoxy neuroglobin.

    Science.gov (United States)

    Lutz, Stephan; Nienhaus, Karin; Nienhaus, G Ulrich; Meuwly, Markus

    2009-11-19

    Neuroglobin (Ngb) belongs to the large family of globular heme proteins capable of binding small gaseous ligands such as O(2), CO, or NO within their active site. In this work, we have analyzed CO migration pathways in photolyzed NgbCO using molecular dynamics (MD) simulations in combination with Fourier transform infrared temperature derivative spectroscopy (FTIR-TDS). A total of 55 ns of MD simulation was analyzed to explore the approximately 300 A(3) internal Ngb cavity. Overall, the simulations differentiated between eight possible docking sites, three of which were also identified experimentally. Low-temperature FTIR-TDS experiments on wild-type (wt) and F28W mutant NgbCO revealed that a small fraction of ligands migrates from site B to site C from which they rebound after slow cool illumination. For the F28L mutant, however, population of site C was not observed. In agreement with these findings, the simulations at 20 K showed ligand transfer between sites B and C for wt Ngb, but not for the F28L mutant. The ligand migration network could be mapped out and two key gate residues, Phe28 and Pro52, were identified. Ligand population analysis from the MD simulations revealed a direct relation between the size of the B10 side chain (Phe28 in wild-type Ngb) and the barrier against migration. Barriers for the transition of photodissociated CO from the distal pocket to the Xe4 site in Ngb are lower by up to 4 kcal/mol compared to myoglobin, suggesting that ligand migration between different docking sites is more facile in Ngb than in myoglobin.

  20. Definition of Household Membership in International Migration Surveys

    Directory of Open Access Journals (Sweden)

    Turgay Ünalan

    2005-01-01

    Full Text Available Using data from national surveys conducted within the scope of the Eurostat project titled “Push and Pull Factors of International Migration”, analyses are presented using different definitions (narrow versus wide of household membership in migrant-sending countries (Egypt, Ghana, Morocco, Senegal and Turkey to see if different definitions are helpful in identifying and increasing the number of migrants who are or was a part of those households. When broad definition was used, the increase in the international migrant members was especially considerable in recent and current migrant households. The findings demonstrated that it was possible to trace an important number of international migrants back in their country of origin and to collect data using proxy interviews. However, it was still impossible to survey emigrants who left the country as a household, those who were not expected to return to the household, those belonging to some dissolved households, or those who died.

  1. Recent International and Domestic Migration in the Maltese Archipelago: An Economic Review

    Directory of Open Access Journals (Sweden)

    Rose Marie Azzopardi

    2012-05-01

    Full Text Available Migration strategies often permit densely populated island territories to alleviate unemployment, ease pressure on limited resources, and compensate for the absence of economic diversification. This paper evaluates two types of recent migratory flows affecting the Maltese archipelago: international migration to and from the islands triggered or intensified by European Union membership; and domestic, inter-island movements between the ‘mainland’ (Malta and the smaller island (Gozo.The descriptive statistics used are based on published data, whilst the qualitative evaluation is derived from focus groups and interviews with stakeholders. Conclusions suggest that emigration remains an overall positive experience at the individual level, with constructive spill-over effects, mingling of cultures and better use of resources at the national level. Such benefits can be expected to increase if authorities design policies which encourage rather than discourage migratory flows.

  2. International Migration with Heterogeneous Agents: Theory and Evidence for Germany, 1967-2009

    DEFF Research Database (Denmark)

    Brücker, Herbert; Schröder, Philipp

    2012-01-01

    of German migration stocks and flows since 1967. We find that (i) panel-unit root tests reject the hypothesis that migration flows and the explanatory variables are integrated of the same order, while migration stocks and the explanatory variables are all I(1) variables, and (ii) the hypothesis......Temporary migration, though empirically relevant, is often ignored in formal models. This paper proposes a migration model with heterogeneous agents and persistent cross country income differentials that features temporary migration. In equilibrium there exists a positive relation between the stock...... of migrants and the income differential, while the net migration flow becomes zero. Consequently, existing empirical migration models, estimating net migration flows, instead of stocks, may be misspecified. This suspicion appears to be confirmed by our investigation of the cointegration relationships...

  3. Does International Migration Lead to Divorce? Ghanaian Couples in Ghana and Abroad

    NARCIS (Netherlands)

    Caarls, K.; Mazzucato, V.

    2015-01-01

    This article examines the effects of international migration on the probability of divorce among Ghanaian couples in 2009. Couples that experienced joint migration, and those where the husband and/or the wife migrated alone are compared with couples with no migration experience. The relationship

  4. Does International Migration Lead to Divorce? Ghanaian Couples in Ghana and Abroad

    NARCIS (Netherlands)

    Caarls, K.; Mazzucato, V.

    2015-01-01

    This article examines the effects of international migration on the probability of divorce among Ghanaian couples in 2009. Couples that experienced joint migration, and those where the husband and/or the wife migrated alone are compared with couples with no migration experience. The relationship bet

  5. Post war migration flows and disparities in mortality from age 50 onwards

    DEFF Research Database (Denmark)

    Zarulli, Virginia

    Compositional changes due to internal migration can modify the distribution of health outcomes, death rates and socioeconomic characteristics of a specific geographical area. Migration flows may affect patterns of socioeconomic inequalities in mortality as well. However, despite these inequalities...... status, from age 50 onwards, in Turin, one of the main industrial areas of the country, where many low educated individuals from the southern regions migrated to Turin with seeking jobs in the car factories. Migrants might be selected in terms of robustness because of the healthy migrant effect. However......, lowly educated individuals are employed in heavier and riskier jobs. They thus undergo a faster health selection due to exposure to higher mortality risk that selects the most robust individuals. This paper hypothesized that the interplay of these mechanisms might have produced a homogenization process...

  6. Internal migration and health: premarital sexual initiation in Nigeria.

    Science.gov (United States)

    Mberu, Blessing Uchenna; White, Michael J

    2011-04-01

    The high rates of youth migration to urban and economic centers, in the context of persistent poverty and devastating HIV/AIDS burden, have raised intricate social policy challenges in developing countries. Using the 2008 Nigeria Demographic and Health Survey data, descriptive statistics, Kaplan-Meier survival curves and discrete-time hazard regression models, this study examines the patterns of internal migration and sexual initiation among never-married Nigerian youth aged 15-24. We find that migrants generally show stronger association than non-migrants, and urban-rural and rural-rural migrants particularly show the strongest independent association with premarital sexual initiation. Other significant covariates are age, religion, ethnic origin, educational attainment, independent living arrangement, formal employment and exposure to the mass media. The findings highlight the direct importance of youth migration in understanding and addressing the challenges of premarital sexual behavior and the need for behavior change policies and programs to be sensitive to the complex contextual nuances across youth groups in one country. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. The role of language in shaping international migration

    DEFF Research Database (Denmark)

    Pytlikova, Mariola; Adsera, Alicia

    's language and/or widely spoken languages (or ease to quickly learn it) plays a key role in the transfer of human capital from the source country to another country and boosts the immigrant's success at the destination's labor market. We use data on immigration flows and stocks of foreigners in 27 OECD...... and climate shocks, migrant networks, language and aspects of "cultural distance". In that regard, the more "foreign" or distant the new culture is and the larger the language barrier is, the higher are the costs of an individual to migrate to a particular destination. Fluency in destination country...... destination countries from 130 source countries for the years 1985-2006. In addition to standard covariates from gravity models, we include a set of indices of language distance to study their association to the observed flows: (1) an index ranging from 0 to 1 that measures the distance between the family...

  8. Embedding international migration: the response of Bolivian local governments and NGOs to international migraton.

    NARCIS (Netherlands)

    Nijenhuis, G.

    2010-01-01

    International migration is an integral part of the lives of many people in the South, and many households add remittances to their income in order to finance the daily costs of living that cannot be met by their traditional source of income. In the literature, a debate has emerged on the impacts of

  9. International Migration with Heterogeneous Agents: Theory and Evidence

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Brücker, Herbert

    Temporary migration, though empirically relevant, is often ignored in formal models. This paper proposes a migration model with heterogeneous agents and persistent cross country income differentials that features temporary migration. In equilibrium there exists a positive relation between the stock...

  10. Construction of the migration flows forecasting into Russian regions

    Directory of Open Access Journals (Sweden)

    Aleksandr Aleksandrovich Tarasyev

    2013-06-01

    Full Text Available This paper presents a dynamic model that can predict the dynamics of migration flows between source countries and host regions, as well as the dynamics of wage levels there. The model is constructed within the framework of neoclassical economics and human capital theory in continuous time. Thanks to liberalization of migration policy in Russia in 2007, the model could be successfully employed to Russian regions and the Commonwealth of Independent States (CIS, which have visa-free entry regulations with the Russian Federation. Employing the model on statistical data, we forecast the number and origin composition of foreign labor force from the CIS into Russian regions for 2010-2016. The purpose of our further research is to classify migrants by skills

  11. E.U. VERSUS O.E.C.D. - MIGRATION FLOW UNDER THE LABOUR TAXATION IMPACT

    Directory of Open Access Journals (Sweden)

    LAZAR PAULA

    2015-07-01

    Full Text Available In a world governed by the freedom of movement, production factors – capital, labour and consumption – can “run” from on territory to another bringing along positive and negative effects, just as well. Labour, the second in line of “run away” production factors, has a great impact upon a state economy generating sustainable growth or increasing budgetary revenues This paper presents for a period of 7 years, for both European (UE-28 and international (OECD level, the migration flow under the labour taxation impact (it is well known that more than 75% of the migration flow is work force related. The authors found that even if both areas are attracting labour force the reasons for doing that are completely different – while for the OECD member states and non-EU member states there will always be the “occident fascination” in the Europeans are “voting with their feet”.

  12. Does Migration Make You Happy? A Longitudinal Study of Internal Migration and Subjective Well-Being (discussion paper)

    NARCIS (Netherlands)

    Nowok, B.; Van Ham, M.; Findlay, A.; Gayle, V.

    2011-01-01

    The majority of modelling studies on consequences of internal migration focus almost exclusively on the labour market outcomes and the material well-being of migrants. We investigate whether individuals who migrate within the UK become happier after the move than they were before it and whether the

  13. International Migration from the Dominican Republic: Findings from a National Survey.

    Science.gov (United States)

    Ugalde, Antonio; And Others

    1979-01-01

    A profile of international Dominican migrants, most of whom come to the United States, is provided. Reasons for migration by age, sex, and social status are discussed and return migration patterns are examined. (Author/MC)

  14. Flow-induced differential lateral migration of deformable particles by inner/outer viscosity ratio

    Science.gov (United States)

    Chen, Yeng-Long; Wang, Shih-Hao; Yeh, Wei-Ting

    2016-11-01

    We investigate the practicality of flow-driven separation of deformable particles (DP) such as cells, droplets, and capsules in microfluidic flow. We use lattice Boltzmann-immersed boundary method to model the hydrodynamic coupling between DP and the fluid. We find that whether a DP migrates towards the wall or to the center at steady state depends strongly on particle Reynolds number Re, capillary numbers Ca, and viscosity ratio λ. The lateral steady state position d* and velocity is determined by the competition between the inertia- and deformation-driven forces. In the deformation-dominated regime (Ca >> Re), DP migrates towards the channel centerline and flow faster for sufficiently small λ. In the inertia-dominated regime (Ca<flow slower for small λ. For sufficiently large λ, DP migrates towards the wall as the inertia-driven lift effects increase and the particle velocity decreases. In the intermediate regime (Ca Re), we find that d* has non-monotonic dependence on λ, leading to complicated dependence of particle velocity. We find that the non-monotonic trend is a consequence of inertia-deformation coupling, and only occurs if the inertia- and deformation-driven lift effects are comparable. This result could provide be further utilized for separating soft particles with different internal fluid property. MOST Taiwan, NCTS.

  15. Age and Educational Selectivity among Migration and Human Capital Flows in the West.

    Science.gov (United States)

    Evenson, James A.

    This paper quantifies and analyzes the total flows of human capital moving in and out of the West over time as a result of interregional migration. Particular emphasis is placed on analyzing the "age-education" interaction effect of migration on flows of human capital. Migration was highly selective of the young and/or highly educated…

  16. International human rights law aspects of forced migrations, evictions and displacement: current issues and challenges

    OpenAIRE

    Scholten, Andrew

    2016-01-01

    The aim of this paper is an analysis of the categories of evictions, forced migrations and internal displacement in the context of international human rights law. Forced migrations and selected categories of internal displacement are important issues of international human rights law and international humanitarian law for more than forty years. The UDHR, adopted in 1948, does not contain any provisions related to forced human mobility and internal displacement. Despite this fact ...

  17. Boundary element method for internal axisymmetric flow

    Directory of Open Access Journals (Sweden)

    Gokhman Alexander

    1999-01-01

    Full Text Available We present an accurate fast method for the computation of potential internal axisymmetric flow based on the boundary element technique. We prove that the computed velocity field asymptotically satisfies reasonable boundary conditions at infinity for various types of inlet/exit. Computation of internal axisymmetric potential flow is an essential ingredient in the three-dimensional problem of computation of velocity fields in turbomachines. We include the results of a practical application of the method to the computation of flow in turbomachines of Kaplan and Francis types.

  18. Scottish emigration in the 1980s: a migration channels approach to the study of skilled international migration.

    Science.gov (United States)

    Findlay, A M; Garrick, L

    1990-01-01

    "British emigration is now dominated by skilled transient movements rather than traditional settler emigration movements. This switch requires new frameworks for migration analysis. A migration channels approach is advocated with attention focused on the roles of the internal labour markets of multi-national companies, international recruitment agencies and international skill transfers by small- and intermediate-sized companies in moulding contemporary skilled migration. The migration processes which have emerged in relation to the operation of these three channels can be differentiated in terms of migrant characteristics, the status of migration contracts and patterns of movement. The regional dimension is highlighted in this article by contrasting the experience of recent Scottish emigration with that of the South-East of England. Three data sources (the International Passenger Survey, the results of a survey questionnaire, and company case study material) are employed to illustrate the nature of Britain's main migration channels. It is argued that the three channels are responsible for a selective structuring of the British migration system." excerpt

  19. Internal migration and maternal health service utilisation in Jiangsu, China.

    Science.gov (United States)

    Gu, Hai; You, Hua; Ning, Weiqing; Zhou, Hua; Wang, Jianming; Lu, Ying; Sun, Jun; Kou, Yun; Dong, Hengjin

    2017-02-01

    To investigate the use of maternal health care services by internal migrants in view of their migration status. Cross-sectional household survey in two cities of Jiangsu Province. Questions elicited data on socioeconomic information and MHC service use (pre-natal examination, post-natal visit, pre-natal health education). Chi-square tests and multivariate logistic regression analyses were used to identify factors associated with MHC service use. A total of 946 married women were recruited, of whom 22.3% were internal migrants. Compared to local residents, migrants were five times less likely to attend pre-natal examinations (84.4% vs. 91.7%; OR = 0.49, P = 0.002), three times less likely to have post-natal visits (15.6% vs. 50.2%; OR = 0.18, P Internal migrants in Jiangsu Province underuse MHC services to a significant degree. More attention needs to be paid to pregnant migrant women, as they are vulnerable group in society. © 2016 John Wiley & Sons Ltd.

  20. [New international migrations and migratory models in South European countries].

    Science.gov (United States)

    De Filippo, E; Pugliese, E

    1996-01-01

    Trends in international migration in the Mediterranean European countries over the course of the 1980s are reviewed. "Particular attention is paid to the different factors that explain the arrival of these migratory fluxes during a period of economic recession and in areas where there is a co-presence of immigration, emigration and unemployment. The involvement of southern European countries as target countries for immigration is not seen as a simple consequence of the [restrictive policies] practiced in the Seventies by European countries with traditional immigration; the push towards these countries as well as the pull to the same are also considered, particularly the acceleration of the internationalization process of the labor markets, the characteristics of the labor markets, and processes of segmentation and tertiarization." (EXCERPT)

  1. International migration and the "moral" economy of the "Barani" peasantry.

    Science.gov (United States)

    Khan, A F

    1991-01-01

    International migration and the "barani" peasantry are explained in terms of a subsistence ethic in rainfed agricultural areas of northern Pakistan. It is postulated that economic decisions of the "barani" are rational and are part of a willed order which reflects the economic, political, social and cultural aspects of a deliberately organized style of living. This functional structure is discussed in terms of the motivational concerns of the "biraderi" and the kinship and worksharing patterns and the household structure. There is selectivity in the migration pattern and the decision is made with the collective welfare of the household in mind. The migrant profile is one of single, young males about 24-35 years; most fall in the 26-32 age group. 67% are unmarried, but there is motivation to marry in order to make claims on fathers' lands and fulfill dowry payments and become more marriageable. Also, villagers desire to expand the number of "biraderi" which strengthens the socioeconomic foundation. Marriage is also related to earning potential. The migration impact is felt in terms of the absence, which results in a loss of labor, but usually households cope effectively. Another impact was one of remittances, which make a considerable difference in household income. From a sample of households taken in 1980-1984, over 65% of migrant households received over 75% of their income from migrant labor. Only 1 household received 50% of their income from migrant labor. It is estimated that 64% of annual migrant's earnings and 87% of migrant's savings were remitted. The impact was also felt in the use of remittances, which in order to importance, satisfied the needs of the households, their aspirations, and access to investment opportunities. A significant portion of income was spent on basic needs: food, clothing/footwear, and other related items, and health. A portion also went to savings. This occurred in order to achieve security and a measure of control over their lives

  2. Migration and Adult Language Learning: Global Flows and Local Transpositions

    Science.gov (United States)

    Burns, Anne; Roberts, Celia

    2010-01-01

    In the 21st century, global flows politically, socially, economically, and environmentally are creating widespread movements of people around the world and giving rise to increased resettlements of immigrants and refugees internationally. The reality in most countries worldwide is that contemporary populations are multifaceted, multicultural,…

  3. An Exploratory Study of Internal Migration and Substance Use Among an Indigenous Community in Southern Mexico.

    Science.gov (United States)

    Pinedo, Miguel; Sim, D Eastern Kang; Giacinto, Rebeca Espinoza; Luisa Zuñiga, Maria

    2016-01-01

    The primary aim of this study was to explore the association between internal migration experience within Mexico and lifetime substance use among a sample of 442 indigenous persons from Yucatan, Mexico. Adjusting for potential confounding, correlates of lifetime substance use were assessed among participants with and without internal migration experience. Internal migration to a tourist destination was independently associated with higher odds (adjusted odds ratio: 2.1; 95% confidence interval: 1.3-3.4) of reporting lifetime substance use. Findings suggest that environmental contexts of internal migration may be of importance in shaping vulnerability to substance use.

  4. Immigration and Internal Migration "Flight" from US Metropolitan Areas: Toward a New Demographic Balkanisation.

    Science.gov (United States)

    Frey, William H.

    1995-01-01

    Examines migration dynamics for metropolitan areas that suggest immigration and internal migration processes are leading to a greater demographic balkanization--a spatial segmentation of the population by race, ethnicity, and socioeconomic status across metropolitan areas. A brief overview of migration at the state level is also provided. (GR)

  5. Immigration and Internal Migration "Flight" from US Metropolitan Areas: Toward a New Demographic Balkanisation.

    Science.gov (United States)

    Frey, William H.

    1995-01-01

    Examines migration dynamics for metropolitan areas that suggest immigration and internal migration processes are leading to a greater demographic balkanization--a spatial segmentation of the population by race, ethnicity, and socioeconomic status across metropolitan areas. A brief overview of migration at the state level is also provided. (GR)

  6. Internal Migration Determinants: Evidence from Northern Region of ...

    African Journals Online (AJOL)

    2016-05-01

    May 1, 2016 ... important determinants of migration decisions, while gender is not. ..... the result of the data analysis revealed that majority of both current and .... of females in migration is perhaps due to changes in gender roles at the study.

  7. Financial Flows and the International Monetary System

    OpenAIRE

    Passari, Evgenia; Rey, Hélène

    2015-01-01

    Le fichier attaché est le working paper daté du 18 décembre 2014.; International audience; We review the findings of the literature on the benefits of international financial flows and find that they are quantitatively elusive. We then present evidence on the existence of a global cycle in gross cross-border flows, asset prices and leverage and discuss its impact on monetary policy autonomy across different exchange rate regimes. We focus in particular on the effect of US monetary policy shoc...

  8. Costs and benefits of the international labor migration

    Directory of Open Access Journals (Sweden)

    Alina Hagiu

    2007-05-01

    Full Text Available Migration has been an important part of the transition process and it's effects are complex including significant changes in attitudes and norms that are relevant for democratic processes. Migration changes the way of life, leads to social-economical and cultural modification, at a continuous readjustment of social organization and assimilation and rejection problems.The amplitude and intensity of migrating fluxes, its dynamic as well as the peculiarity of migrating persons (social level, professional preparation, age, sex is different according with the scope of migration ( work, obliged change of home, refugee, making or gathering the family.

  9. The relationship between international migration, trade, and development: some paradoxes and findings

    OpenAIRE

    J. Edward Taylor

    2006-01-01

    The interactions among trade, international migration, and economic development in migrant-sending areas are complex, and paradoxes abound. This paper summarizes global trends in world migration and remittances, discusses some paradoxes surrounding the trade-migration-development relationship, and reports findings from new research on Mexico-to-U.S. migration, using data from rural Mexico. It concludes with some thoughts about designing policies to raise the development potential of remittanc...

  10. Occupational change, employer change, internal migration, and earnings.

    Science.gov (United States)

    Krieg, R G

    1997-02-01

    "In this paper I use microdata from the [U.S.] Panel Study of Income Dynamics to measure the financial returns to intercounty and interstate migration for individuals in a temporal framework accounting for gains that accrue over time.... To account for the indirect effects of migration on earnings, explanatory variables are created by interacting migration status with: (1) occupational change, (2) employer change and (3) changes in both occupation and employer. These interaction terms are then included in the earnings functions. Earnings are estimated for three years subsequent to the migration decision to account for the financial returns to migration accruing over time. Results indicate that, when estimating earnings, the use of a simple migration dummy variable will mask the indirect effects of migration on earnings."

  11. Internal Migration, Regional Labour Market Dynamics and Implications for German East-West Disparities – Results from a Panel VAR

    DEFF Research Database (Denmark)

    Alecke, Björn; Mitze, Timo; Untiedt, Gerhard

    :That is, along with a second wave of East-West movements around 2001 net flows out of East Germany were much higher than expected after controlling for its weak labour market and macroeconomic performance. Since this second wave is also accompanied by a gradual fading out of economic distortions......This paper analyses the causal linkages between regional labour market variables and internal migration flows among German states between 1991–2006. We adopt a Panel VAR approach to identify the feedback effects among the variables and analyse the dynamic properties of the system through...... impulseresponse functions.We also use the model to track the evolution of the particular East-West migration since re-unification aiming to shed more light on the East German “empirical puzzle”, characterized by lower migration responses than expected from the regional labour market position relative to the West...

  12. Migration and international relations: cooperation and control in the European Community.

    Science.gov (United States)

    Hollifield, J F

    1992-01-01

    "In this article I have developed a political-economic framework for understanding international migration in postwar Europe and the United States." The author begins by reviewing four theories of international relations and gives a short critique of their main assumptions. He "finds that international migration reveals a contradiction between the main economic purpose of the postwar international order--to promote exchange--and the national perquisites of sovereignty and citizenship."

  13. [Agricultural structures and internal migration in a historical perspective: Latin American case studies].

    Science.gov (United States)

    Balan, J

    1981-01-01

    This study is concerned with the ways in which changes in the structure of rural life influence internal migration in Latin America. The author describes how changes such as the abolition of slavery affected Peru and Bolivia and how the expansion of the international grain market affected Argentina, particularly regarding migration. Recent changes considered include the mechanization of agriculture and the decline of immigration.

  14. Networks and selection in international migration to Spain

    OpenAIRE

    Neubecker, Nina; Smolka, Marcel; Steinbacher, Anne

    2012-01-01

    This paper provides new evidence on migrant networks as determinants of the total size (scale) and skill structure of migration, using aggregate data from a recent migration boom to Spain. We draw upon McFadden (1984, 1422-1428) in order to develop and apply a three-level nested multinomial logit migration model. Our model accommodates varying degrees of similarity of destinations located in the same region (or the same country), allowing for a rich structure of substitutability across altern...

  15. Networks and Selection in International Migration to Spain

    DEFF Research Database (Denmark)

    Neubecker, Nina; Smolka, Marcel; Steinbacher, Anne

    This paper provides new evidence on migrant networks as determinants of the scale and skill structure of migration, using aggregate data from a recent migration boom to Spain. We develop a three-level nested multinomial logit migration model. Our model accommodates varying degrees of similarity...... of destinations located in the same region (or the same country), allowing for a rich structure of substitutability across alternative destinations. We find strong positive network effects on the scale of migration and a strong negative effect on the ratio of high-skilled to low-skilled migrants. Simplifying...

  16. The benefits and caveats of international nurse migration

    Directory of Open Access Journals (Sweden)

    Hongyan Li

    2014-09-01

    Full Text Available Worldwide, there is a dramatic shortage of nurses. An increase in the migration of nurses from their home countries to recipient countries is having a global effect on the healthcare system. This global phenomenon stems from historical, economical, social, and political factors. Migration has a significant impact on both the individual and national level. This article summarizes the factors that contribute to nurse migration form the perspective of the source and recipient countries. Additionally, the impacts and issues surrounding nurse migration were also analyzed.

  17. The national and international implications of a decade of doctor migration in the Irish context.

    LENUS (Irish Health Repository)

    Bidwell, Posy

    2012-12-17

    BACKGROUND: Between 2000 and 2010, Ireland became increasingly dependent on foreign-trained doctors to staff its health system. An inability to train and retain sufficient doctors to meet demand is the primary reason for the dependence on foreign-trained doctors. By 2008 the proportion of foreign-trained doctors was the second highest in the OECD. This increased dependence on international medical migration has both national and international policy implications. METHODS: Registration data were obtained from the Medical Council of Ireland (MCI) for a 10-year period: 2000-2010. Data indicate country of qualification but not nationality. The total number of registrants and entrants (n) was determined for each year. Immigration data were also obtained on the number of work visas issued to doctors. Registration and visa data were then compared in order to estimate doctor migration to Ireland 2000-2010. RESULTS: The proportion of foreign-trained doctors rose from 13.4% of all registered doctors in 2000 to 33.4% by 2010. The largest increase was in foreign-trained doctors from outside the EU, rising from 972 (7.4%) in 2000 to 4740 (25.3%) of registered doctors in 2010. The biggest source country in 2000 was Pakistan. By 2010, South Africa had become the biggest source country. The number of foreign-trained doctors from other EU countries doubled from 780 in 2000 to 1521 in 2010. CONCLUSIONS: Registration data are likely to over-estimate and visa data under-estimate the numbers of doctors actively working in Ireland. However, they serve to illustrate Ireland\\'s rapidly increasing and potentially unsustainable reliance on foreign-trained doctors; and to highlight the need for better data to measure migratory flows. Improved measurement of health worker migration is necessary both for national workforce planning and to fulfil the requirements of the WHO Global Code on the International Recruitment of Health Personnel.

  18. Relative deprivation and internal migration in the United States: A comparison of black and white men.

    Science.gov (United States)

    Flippen, Chenoa

    2013-03-01

    While the link between geographic and social mobility has long been a cornerstone of sociological approaches to migration, recent research has cast doubt on the economic returns to internal U.S. migration. Moreover, important racial disparities in migration patterns remain poorly understood. Drawing on data from the 2000 census, I reappraise the link between migration and social mobility by taking relative deprivation into consideration. I examine the association between migration, disaggregated by region of origin and destination, and absolute and relative earnings and occupational prestige, separately by race. Findings lend new insight into the theoretical and stratification implications of growing racial disparities in migration patterns; while both blacks and whites who move north-south generally average lower absolute incomes than their stationary northern peers, they enjoy significantly higher relative social position. Moreover, the relative "gains" to migration are substantially larger for blacks than whites. The opposite patterns obtain for south-north migration.

  19. Migration and depressive symptoms in migrant-sending areas: findings from the survey of internal migration and health in China.

    Science.gov (United States)

    Lu, Yao; Hu, Peifeng; Treiman, Donald J

    2012-08-01

    China has experienced large-scale internal migration and growing mental health disorders. Limited research has examined the relationship between the two processes. We examined the association between labor out-migration and depressive symptoms of family members left behind in migrant-sending areas. We conducted a multistage probability sample survey of Chinese adults in 2008 ("Internal Migration and Health in China"), including 787 people in rural migrant-sending areas. To study whether adults in out-migrant households were more likely to experience depressive symptoms (CES-D) than were adults in non-migrant households, we used multivariate regressions and adjusted for a wide range of confounding factors and for the complex sampling design. Adults in households with labor out-migrants were more likely to report depressive symptoms than those in households without out-migrants, presumably a result of the absence of family members. However, monetary remittances from labor migrants buffered the mental health costs of out-migration. Labor out-migration has important consequences for the mental health in migrant-sending communities. There is an urgent need to address the psychological costs of migration and to promote regular remittances.

  20. International Migration and Transnational Ethics of Well-Being

    NARCIS (Netherlands)

    D.R. Gasper (Des)

    2009-01-01

    textabstract__Abstract__ Migration involves a search for well-being and security, but is not guaranteed to bring either. In the short run it quite often reduces both. What are the hoped for benefits for which the risks are undertaken? Insecurity can generate migration, and in the case of refugees f

  1. [A historical survey of international migration of China population].

    Science.gov (United States)

    Zhu, G

    1987-07-01

    Chinese migration trends in various periods of China's history are discussed. From the earliest times to the present, migration patterns seem unique to each period: 1) Early period of emigration (Qin-Tang Dynasties): The earliest recorded instance of emigration occurred during the Qin dynasty when a traveler went to what is now the Philippines. In the following dynasties, even though migration was limited to religious men and merchants who went abroad and returned to China, the process of migrating was established. 2) Tang to Ming Dynasties (Self-initiated migration): Tang Dynasty records show the beginnings of Chinese residence abroad in Arabia. Land and sea travel developed further, and majority of emigres left China for political, religious or economic reasons. 3) Post-Ming Dynasty (Forced migration): This is a period beginning with the Opium War, where 2 groups, indentured servants and those who were able to purchase their own fare, emigrated as laborers because of necessity. The population on the coast, which had risen dramatically by the 1900's, was subject to war, official corruption, poverty and disease. Migration reached a peak between 1851-1875 when 1,280,000 Chinese left the country, settling mostly in Southeast Asia. Between 1847-1873, it is estimated that between 22%-64% perished along the way. 4) WWI-1949 (Motivated migration): The consequences of 2 world wars and the Great Depression were cause for another mass migration from China for political and economic reasons. This time, however, emigres were not limited to the very poor; also, a large number of overseas Chinese eventually returned to the mainland. Between 1930-34, 350,000 more Chinese returned than left. 5) Post-1949 (A new era): In the 1950s large numbers of overseas Chinese returned to the mainland. In 1978-82, over 4000 Chinese returned to Guangdong alone. A new phenomenon has appeared: migration tends to be limited to visits to relatives or to travel for pleasure or education.

  2. Development of international labor migration in the dynamics of globalization processes

    Directory of Open Access Journals (Sweden)

    Rubinskaya Eteri, D.

    2015-03-01

    Full Text Available The current characteristics of international migration caused by the qualitative changes that occur in the global economy under influence of increasing globalization. The paper attempts to suggest periodization of the global economy development and to identify features of international labor migration occurred under the influence of deep changes in the world economy. During this period, the author identifies three stages in the formation of globalization, the transition criterion from one to other is the degree of world economy changes under the influence of the productive forces development and the major social and political transformations resulted in qualitative changes in the processes of international labor migration. At the same time in the context of globalization the place and role of international labor migration changes in the global economy system: migration becomes a means of promoting the globalization of countries and regions, the most important factor of demographic development and economic growth.

  3. Piezoelectric Energy Harvesting in Internal Fluid Flow

    Directory of Open Access Journals (Sweden)

    Hyeong Jae Lee

    2015-10-01

    Full Text Available We consider piezoelectric flow energy harvesting in an internal flow environment with the ultimate goal powering systems such as sensors in deep oil well applications. Fluid motion is coupled to structural vibration via a cantilever beam placed in a converging-diverging flow channel. Two designs were considered for the electromechanical coupling: first; the cantilever itself is a piezoelectric bimorph; second; the cantilever is mounted on a pair of flextensional actuators. We experimentally investigated varying the geometry of the flow passage and the flow rate. Experimental results revealed that the power generated from both designs was similar; producing as much as 20 mW at a flow rate of 20 L/min. The bimorph designs were prone to failure at the extremes of flow rates tested. Finite element analysis (FEA showed fatigue failure was imminent due to stress concentrations near the bimorph’s clamped region; and that robustness could be improved with a stepped-joint mounting design. A similar FEA model showed the flextensional-based harvester had a resonant frequency of around 375 Hz and an electromechanical coupling of 0.23 between the cantilever and flextensional actuators in a vacuum. These values; along with the power levels demonstrated; are significant steps toward building a system design that can eventually deliver power in the Watts range to devices down within a well.

  4. Ligand-Occupied Integrin Internalization Links Nutrient Signaling to Invasive Migration

    Directory of Open Access Journals (Sweden)

    Elena Rainero

    2015-01-01

    Full Text Available Integrin trafficking is key to cell migration, but little is known about the spatiotemporal organization of integrin endocytosis. Here, we show that α5β1 integrin undergoes tensin-dependent centripetal movement from the cell periphery to populate adhesions located under the nucleus. From here, ligand-engaged α5β1 integrins are internalized under control of the Arf subfamily GTPase, Arf4, and are trafficked to nearby late endosomes/lysosomes. Suppression of centripetal movement or Arf4-dependent endocytosis disrupts flow of ligand-bound integrins to late endosomes/lysosomes and their degradation within this compartment. Arf4-dependent integrin internalization is required for proper lysosome positioning and for recruitment and activation of mTOR at this cellular subcompartment. Furthermore, nutrient depletion promotes subnuclear accumulation and endocytosis of ligand-engaged α5β1 integrins via inhibition of mTORC1. This two-way regulatory interaction between mTORC1 and integrin trafficking in combination with data describing a role for tensin in invasive cell migration indicate interesting links between nutrient signaling and metastasis.

  5. Rush to the border? Market liberalization and urban- and rural-origin internal migration in Mexico.

    Science.gov (United States)

    Villarreal, Andrés; Hamilton, Erin R

    2012-09-01

    In this study we examine the social and economic factors driving internal migration flows in Mexico. We pay particular attention to the effect that economic liberalization has had in encouraging migration to border cities. Our analysis of the origin and destination of migrants is carried out at a finer level of geographical detail than ever before. Microdata files from the 2000 population census allow us to distinguish urban- and rural-origin migrants to the largest 115 cities and metropolitan areas in the country. Our results indicate that economic liberalization, measured by the level of foreign investment and employment in the maquiladora export industry, strongly influences migrants' choice of destinations. However, economic liberalization fails to fully account for the attraction of the border, as do the higher emigration rates to the United States from border cities. Our analysis also reveals that migrants to the border region and to cities with high levels of foreign investment are younger, less educated and more likely to be men than migrants to other parts of Mexico. Rural migrants are significantly more likely to move to the border and to cities with high levels of foreign investment than urban migrants. The results of our study have important implication for other countries opening their economies to foreign investment and international trade.

  6. International Workshop on Traffic and Granular Flow

    CERN Document Server

    Herrmann, Hans; Schreckenberg, Michael; Wolf, Dietrich; Social, Traffic and Granular Dynamics

    2000-01-01

    "Are there common phenomena and laws in the dynamic behavior of granular materials, traffic, and socio-economic systems?" The answers given at the international workshop "Traffic and Granular Flow '99" are presented in this volume. From a physical standpoint, all these systems can be treated as (self)-driven many-particle systems with strong fluctuations, showing multistability, phase transitions, non-linear waves, etc. The great interest in these systems is due to several unexpected new discoveries and their practical relevance for solving some fundamental problems of today's societies. This includes intelligent measures for traffic flow optimization and methods from "econophysics" for stabilizing (stock) markets.

  7. Religion and International Migration: A Case Study of Ukraine

    Directory of Open Access Journals (Sweden)

    Wadim Strielkowski

    2016-06-01

    Full Text Available This paper studies the relationships between religion and migration in modern-day Ukraine. We focus on Ukraine’s numerous churches and their attitude toward the phenomenon of emigration, their relevant activities with regard to the outward migration from the country, and the migration experiences and intentions of the believers. We find that the Greek Catholic Church has put special attention on the emigration phenomenon in its social doctrine, while the doctrines of other churches have been less elaborate, both in general terms and with regard to the issue of external migration in particular. Moreover, we demonstrate that worshippers belonging to the different churches have very similar growing concerns about the negative effects of Ukraine’s economic development—social divide and unemployment in particular.

  8. Improved measures for the cross-national comparison of age profiles of internal migration.

    Science.gov (United States)

    Bernard, Aude; Bell, Martin; Charles-Edwards, Elin

    2014-01-01

    We develop and demonstrate the application of a concise set of measures intended to encapsulate key features of the age profile of internal migration and highlight the significant differences that exist between nations in these profiles. Model schedules have been the most common method of comparing internal migration patterns but issues related to the estimation and interpretation of their parameters hinder their use for cross-national comparison. We demonstrate that the interpretation of exponential coefficients as rates of ascent and descent does not best reflect the slopes of migration age profiles, and we propose more consistent measures based on the rate of change in migration intensity. We demonstrate, through correlation and factor analysis, that most of the inter-country variance in migration age profiles is captured by the age at and intensity of peak migration. The application of these two indicators to 25 countries reveals significant differences between regions.

  9. Monetary policy games and international migration of labor in interdependent economies.

    Science.gov (United States)

    Agiomirgianakis, G M

    1998-01-01

    "In this paper we incorporate the possibility of international migration into a monetary policy game played by governments in unionized interdependent economies. We show that contrary to usual presumptions, established by earlier studies that ignore the possibility of international migration, inter-government cooperation in the monetary field may well turn out to be advantageous. This has important implications for the European economies, since it suggests that measures taken towards encouraging international migration within EU [the European Union] will not only harmonize the European labor markets but will also make monetary policy cooperation within Europe, as required by the Maastrict Treaty, more advantageous." excerpt

  10. On Problems with Downscaling in Internal Flows

    Institute of Scientific and Technical Information of China (English)

    Rudolf DVO(R)(A)K

    2005-01-01

    Problems that may accompany downscaling in internal flows are discussed. Non-dimensional similarity parameters (like Re, M, etc.) depend on parameters that scale down fully (e.g., length), or that are specified by design (velocities, cascade geometry), or that are scale invariant (like thermophysical and transport properties of fluids).This fact has to be taken into acount in the similarity considerations. With decreasing Reynolds number the surface forces become of growing importance, however, if not going down directly to microflows the main problems are connected with the three-dimensional flow structure affecting the skin friction, and with the fact that some of the flow phenomena (e.g. vortical structures) cannot fully develop.

  11. Short-term international migration trends in England and Wales from 2004 to 2009.

    Science.gov (United States)

    Whitworth, Simon; Loukas, Konstantinos; McGregor, Ian

    2011-01-01

    Short-term migration estimates for England and Wales are the latest addition to the Office for National Statistics (ONS) migration statistics. This article discusses definitions of short-term migration and the methodology that is used to produce the estimates. Some of the estimates and the changes in the estimates over time are then discussed. The article includes previously unpublished short-term migration statistics and therefore helps to give a more complete picture of the size and characteristics of short-term international migration for England and Wales than has previously been possible. ONS have identified a clear user requirement for short-term migration estimates at local authority (LA) level. Consequently, attention is also paid to the progress that has been made and future work that is planned to distribute England and Wales short-term migration estimates to LA level.

  12. National and International Migration:Reflections on Literature and Some Current Research1

    Institute of Scientific and Technical Information of China (English)

    Nicholas Tapp(Wang Fuwen)

    2013-01-01

    This article gives a review on literature and some current research relevant to na-tional and international migration , and examines the connections between such research in a na-tional context , and the research on international migration .The approaches to migration in migra-tion studies are very complex , and the author suggested that we need to pay attention to all three approaches contrasted by Solinger:the one based on rational calculation , the one based on stress-ing the historico-structural conditions and the one based on social networking analysis .The au-thor also stresses the importance of a network approach taken from the sociology of John Urry in the studies of both national and international migration , and the need to see movement as prima-ry, and productive of place , as much recent anthropological literature has stressed .

  13. Measuring Polycentricity of Mega-City Regions in China Based on the Intercity Migration Flows

    Science.gov (United States)

    Mu, Xiaoyan; Yeh, Anthony G. O.

    2016-06-01

    This paper uses the intercity migration flows to examine relations between Chinese cities, identify the important mega-city regions and measure each region's polycentricity from an interaction perspective. Data set contains the long-term residential migration trajectories of three million Sina weibo users across 345 cities. Cities with close connectivity deployed around one or several mega cities are identified as mega-city regions. Features of the mega-city regions are characterized by the strength of migration flows, density of connections, and regional migration patterns. The results show that the disparities exist in different mega-city regions; most mega-city regions are lack of polycentricity.

  14. MEASURING POLYCENTRICITY OF MEGA-CITY REGIONS IN CHINA BASED ON THE INTERCITY MIGRATION FLOWS

    Directory of Open Access Journals (Sweden)

    X. Mu

    2016-06-01

    Full Text Available This paper uses the intercity migration flows to examine relations between Chinese cities, identify the important mega-city regions and measure each region's polycentricity from an interaction perspective. Data set contains the long-term residential migration trajectories of three million Sina weibo users across 345 cities. Cities with close connectivity deployed around one or several mega cities are identified as mega-city regions. Features of the mega-city regions are characterized by the strength of migration flows, density of connections, and regional migration patterns. The results show that the disparities exist in different mega-city regions; most mega-city regions are lack of polycentricity.

  15. Measuring Gravity in International Trade Flows

    Directory of Open Access Journals (Sweden)

    E. Young Song

    2004-12-01

    Full Text Available The purpose of this paper is two-fold. One is to clarify the concept of gravity in international trade flows. The other is to measure the strength of gravity in international trade flows in a way that is consistent with a well-defined concept of gravity. This paper shows that the widely accepted belief that specialization is the source of gravity is not well grounded on theory. We propose to define gravity in international trade as the force that makes the market shares of an exporting country constant in all importing countries, regardless of their sizes. In a stochastic context, we should interpret it as implying that the strength of gravity increases i as the correlation between market shares and market sizes gets weaker and ii as the variance of market shares gets smaller. We estimate an empirical gravity equation thoroughly based on this definition of gravity. We find that a strong degree of gravity exists in most bilateral trade, regardless of income levels of countries, and in trade of most manThe purpose of this paper is two-fold. One is to clarify the concept of gravity in international trade flows. The other is to measure the strength of gravity in international trade flows in a way that is consistent with a well-defined concept of gravity. This paper shows that the widely accepted belief that specialization is the source of gravity is not well grounded on theory. We propose to define gravity in international trade as the force that makes the market shares of an exporting country constant in all importing countries, regardless of their sizes. In a stochastic context, we should interpret it as implying that the strength of gravity increases i as the correlation between market shares and market sizes gets weaker and ii as the variance of market shares gets smaller. We estimate an empirical gravity equation thoroughly based on this definition of gravity. We find that a strong degree of gravity exists in most bilateral trade, regardless of

  16. The possibilities of least-squares migration of internally scattered seismic energy

    KAUST Repository

    Aldawood, Ali

    2015-05-26

    Approximate images of the earth’s subsurface structures are usually obtained by migrating surface seismic data. Least-squares migration, under the single-scattering assumption, is used as an iterative linearized inversion scheme to suppress migration artifacts, deconvolve the source signature, mitigate the acquisition fingerprint, and enhance the spatial resolution of migrated images. The problem with least-squares migration of primaries, however, is that it may not be able to enhance events that are mainly illuminated by internal multiples, such as vertical and nearly vertical faults or salt flanks. To alleviate this problem, we adopted a linearized inversion framework to migrate internally scattered energy. We apply the least-squares migration of first-order internal multiples to image subsurface vertical fault planes. Tests on synthetic data demonstrated the ability of the proposed method to resolve vertical fault planes, which are poorly illuminated by the least-squares migration of primaries only. The proposed scheme is robust in the presence of white Gaussian observational noise and in the case of imaging the fault planes using inaccurate migration velocities. Our results suggested that the proposed least-squares imaging, under the double-scattering assumption, still retrieved the vertical fault planes when imaging the scattered data despite a slight defocusing of these events due to the presence of noise or velocity errors.

  17. The world economic system and international migration in less developed countries: an ecological approach.

    Science.gov (United States)

    Amankwaa, A A

    1995-01-01

    "This paper analysed net migration within the context of [the] world economic system and urban ecological framework using the structural equation model." The author "employs linear structural equation modelling to examine determinants of international migration, using data from the World Bank World Tables, World Development Reports and the World Bank." (SUMMARY IN FRE AND SPA)

  18. Language Assessment in the Management of International Migration: A Framework for Considering the Issues

    Science.gov (United States)

    Saville, Nick

    2009-01-01

    Given the scope and importance of migration in the 21st century, a comprehensive and cooperative approach to "the management of international migration" is required to provide benefits for both individuals and societies alike; to be successful this cannot be undertaken unilaterally or by governments alone. In this article, the need for…

  19. Microvascular blood flow resistance: Role of red blood cell migration and dispersion.

    Science.gov (United States)

    Katanov, Dinar; Gompper, Gerhard; Fedosov, Dmitry A

    2015-05-01

    Microvascular blood flow resistance has a strong impact on cardiovascular function and tissue perfusion. The flow resistance in microcirculation is governed by flow behavior of blood through a complex network of vessels, where the distribution of red blood cells across vessel cross-sections may be significantly distorted at vessel bifurcations and junctions. In this paper, the development of blood flow and its resistance starting from a dispersed configuration of red blood cells is investigated in simulations for different hematocrit levels, flow rates, vessel diameters, and aggregation interactions between red blood cells. Initially dispersed red blood cells migrate toward the vessel center leading to the formation of a cell-free layer near the wall and to a decrease of the flow resistance. The development of cell-free layer appears to be nearly universal when scaled with a characteristic shear rate of the flow. The universality allows an estimation of the length of a vessel required for full flow development, lc ≲ 25D, for vessel diameters in the range 10 μm red blood cell dispersion at vessel bifurcations and junctions on the flow resistance may be significant in vessels which are shorter or comparable to the length lc. Aggregation interactions between red blood cells generally lead to a reduction of blood flow resistance. The simulations are performed using the same viscosity for both external and internal fluids and the RBC membrane viscosity is not considered; however, we discuss how the viscosity contrast may affect the results. Finally, we develop a simple theoretical model which is able to describe the converged cell-free-layer thickness at steady-state flow with respect to flow rate. The model is based on the balance between a lift force on red blood cells due to cell-wall hydrodynamic interactions and shear-induced effective pressure due to cell-cell interactions in flow. We expect that these results can also be used to better understand the flow

  20. Policy Options for Managing International Student Migration: The Sending Country's Perspective

    Science.gov (United States)

    Gribble, Cate

    2008-01-01

    A consequence of the dramatic rise in international student mobility is the trend for international students to remain in the country in which they study after graduation. Countries such as Australia, the UK and Canada stand to benefit from international student migration, as they are able to fill skill shortages with locally trained foreign…

  1. Investigation of organic matter migrating from polymeric pipes into drinking water under different flow manners.

    Science.gov (United States)

    Zhang, Ling; Liu, Shuming; Liu, Wenjun

    2014-02-01

    Polymeric pipes, such as unplasticized polyvinyl chloride (uPVC) pipes, polypropylene random (PPR) pipes and polyethylene (PE) pipes are increasingly used for drinking water distribution lines. Plastic pipes may include some additives like metallic stabilizers and other antioxidants for the protection of the material during its production and use. Thus, some compounds can be released from those plastic pipes and cast a shadow on drinking water quality. This work develops a new procedure to investigate three types of polymer pipes (uPVC, PE and PPR) with respect to the migration of total organic carbon (TOC) into drinking water. The migration test was carried out in stagnant conditions with two types of migration processes, a continuous migration process and a successive migration process. These two types of migration processes are specially designed to mimic the conditions of different flow manners in drinking water pipelines, i.e., the situation of continuous stagnation with long hydraulic retention times and normal flow status with regular water renewing in drinking water networks. The experimental results showed that TOC release differed significantly with different plastic materials and under different flow manners. The order of materials with respect to the total amount of TOC migrating into drinking water was observed as PE > PPR > uPVC under both successive and continuous migration conditions. A higher amount of organic migration from PE and PPR pipes was likely to occur due to more organic antioxidants being used in pipe production. The results from the successive migration tests indicated the trend of the migration intensity of different pipe materials over time, while the results obtained from the continuous migration tests implied that under long stagnant conditions, the drinking water quality could deteriorate quickly with the consistent migration of organic compounds and the dramatic consumption of chlorine to a very low level. Higher amounts of TOC

  2. The European Refugee Crisis from the Perspective of International Migration Governance

    Directory of Open Access Journals (Sweden)

    Xie Tingting

    2015-11-01

    Full Text Available The influx of refugees in Europe in 2015 has greatly increased, which not only affects the stability and unity of European society, but also exerts certain pressure on its economic development. In the face of the refugee crisis, it is a dilemma for the European countries to choose either humanitarian or national interests. Starting from the impact and challenge that international migration has had on effective governance within national boundaries, this paper uses the theories of international migration to analyze the three basic choices. Further, the authors provide a new way of thinking about the European refugee crisis from the perspective of international migration governance mechanisms. Of course, China should seize the opportunity to become an advocate of the international migration governance mechanism and rule maker of the global governance.

  3. Reasons for internal migration in Estonia 1989-2000 / Mare Ainsaar

    Index Scriptorium Estoniae

    Ainsaar, Mare

    2004-01-01

    Autor tutvustab oma uurimust "Reasons for move: a study on trends and reasons of internal migration with particular interest in Estonia 1989-2000" (Turku University, 2004) Eesti elanikkonna migratsioonist ja selle põhjustest. Skeemid

  4. Migration, international relations and the new Europe: theoretical perspectives from institutional political sociology.

    Science.gov (United States)

    Heisler, M O

    1992-01-01

    The author examines the sociopolitical effects of recent political transformations in Eastern and Central Europe and the formation of the European Community on migration and international relations. Some policy implications are discussed.

  5. Reasons for internal migration in Estonia 1989-2000 / Mare Ainsaar

    Index Scriptorium Estoniae

    Ainsaar, Mare

    2004-01-01

    Autor tutvustab oma uurimust "Reasons for move: a study on trends and reasons of internal migration with particular interest in Estonia 1989-2000" (Turku University, 2004) Eesti elanikkonna migratsioonist ja selle põhjustest. Skeemid

  6. Flow-driven cell migration under external electric fields

    Science.gov (United States)

    Li, Yizeng; Mori, Yoichiro; Sun, Sean X.

    2016-01-01

    Electric fields influence many aspects of cell physiology, including various forms of cell migration. Many cells are sensitive to electric fields, and can migrate toward a cathode or an anode, depending on the cell type. In this paper, we examine an actomyosin-independent mode of cell migration under electrical fields. Our theory considers a one-dimensional cell with water and ionic fluxes at the cell boundary. Water fluxes through the membrane are governed by the osmotic pressure difference across the cell membrane. Fluxes of cations and anions across the cell membrane are determined by the properties of the ion channels as well as the external electric field. Results show that without actin polymerization and myosin contraction, electric fields can also drive cell migration, even when the cell is not polarized. The direction of migration with respect to the electric field direction is influenced by the properties of ion channels, and are cell-type dependent. PMID:26765031

  7. [International migration: global issue, local impact: the example of two parasites].

    Science.gov (United States)

    Jackson, Y

    2009-05-06

    International migration profoundly affects the world's economy and social situation. This global phenomenon modifies the epidemiology of numerous diseases and exposes countries to new challenges in public health. Migrants may export pathologies specific of their country of origin but also develop health problems typical of the country of residence. This article presents some key figures on international migration and explores some of its consequences concerning Chagas disease and malaria epidemiology in Switzerland.

  8. Human Capital Theory and Internal Migration: Do Average Outcomes Distort Our View of Migrant Motives?

    Science.gov (United States)

    Korpi, Martin; Clark, William A W

    2017-05-01

    By modelling the distribution of percentage income gains for movers in Sweden, using multinomial logistic regression, this paper shows that those receiving large pecuniary returns from migration are primarily those moving to the larger metropolitan areas and those with higher education, and that there is much more variability in income gains than what is often assumed in models of average gains to migration. This suggests that human capital models of internal migration often overemphasize the job and income motive for moving, and fail to explore where and when human capital motivated migration occurs.

  9. International migration in Paraguay and the integration of the Southern Cone: a research programme.

    Science.gov (United States)

    Maletta, H

    1992-01-01

    "The purpose of this paper is to bring together some of the general problems that arise in the study of international migration between Paraguay and the countries of the Southern Common Market (with special reference to Argentina, which is the most frequent destination of Paraguayan migration).... The paper first reviews the known information about the emigration of Paraguayans, in general, and to Argentina, in particular, with some references to immigration to Paraguay from bordering countries, as well....A brief survey is made of the impact of the Southern Common Market (Mercosur) on employment and migration, and, finally, some specific problems related to the economic analysis of these migrations are discussed...."

  10. Migration

    NARCIS (Netherlands)

    Gienapp, P.; Candolin, Ulrika; Wong, Bob

    2012-01-01

    This chapter examines how human-induced environmental changes affect migration. It explores how such changes affect conditions along the migration route, as well as the cues that are used in the timing of migration such as the celestial bodies and the planet's magnetic field. It emphasizes the effec

  11. An Introduction to International Migration Studies: European Perspectives

    NARCIS (Netherlands)

    Martiniello, M.; Rath, J.; Martiniello, M.; Rath, J.

    2012-01-01

    No country in Europe is unaffected by migration, although its impact varies from place to place. Immigration is often associated with undermined social cohesion, urban crime, domestic insecurity and public health issues. Immigrants are increasingly regarded as a liability for the welfare state, for

  12. An Introduction to International Migration Studies: European Perspectives

    NARCIS (Netherlands)

    Martiniello, M.; Rath, J.; Martiniello, M.; Rath, J.

    2012-01-01

    No country in Europe is unaffected by migration, although its impact varies from place to place. Immigration is often associated with undermined social cohesion, urban crime, domestic insecurity and public health issues. Immigrants are increasingly regarded as a liability for the welfare state, for

  13. Internal Displacement and Forced Migration within Zimbabwe: An ...

    African Journals Online (AJOL)

    ... in many sub Saharan African countries and Kadane (2011, p.49) contends that ... fact that the mobility and migration of IDPS are rendered invisible in Zimbabwe, ... of IDPs and the children of the IDPs such as their right to (access)education, ...

  14. How job characteristics affect international migration: the role of informality in Mexico.

    Science.gov (United States)

    Villarreal, Andrés; Blanchard, Sarah

    2013-04-01

    Despite the importance given to employment opportunities as a primary motive for migration, previous studies have paid insufficient attention to the kinds of jobs that are more likely to retain workers in their countries of origin. We use information from a panel survey of Mexican adults to examine how job characteristics affect the risk of international migration. The sampling strategy and overall size of the survey allow us to analyze the effect of employment characteristics on migration from urban areas, which have much greater labor market diversity, and to separate our analysis by gender. We also distinguish migrants according to whether they migrate for work or for other reasons. We find informality to be a significant predictor of international migration. Even after controlling for individual factors including workers' wages, as well as various household- and community-level predictors, we find that workers employed in the informal sector have significantly higher odds of migrating than their counterparts in the formal sector. The pervasive nature of informality in many developing countries from which a high proportion of international migrants originate may therefore create a constant supply of workers who are predisposed to migrate. Our findings thus have important implications for a proper understanding of the effects of economic development on migration.

  15. Internal migration effectiveness and income effectiveness in the most populous cities in the United States.

    Science.gov (United States)

    Ambinakudige, Shrinidhi; Parisi, Domenico

    2010-01-01

    In this study, migration data compiled by the Internal Revenue Serve (IRS) and the US Census Bureau for 2006-07 were used to analyse internal migration patterns using migration and income effectiveness for the counties containing the 25 most populous cities in the United States. The results indicated that both large metropolitan and rural counties have lost population and income due to migration. Small metropolitan and non-metropolitan counties closer to cities gained population and income. Counties in South Florida attracted a large number of higher-income migrants from the largest cities in the US. In the last 13 years, New York, Los Angeles and Chicago, the three most populous cities in the US, had negative migration effectiveness. Suburban areas and second-tier cities continued to attract people from large metropolitan areas.

  16. The International Migration in the EU. A Descriptive Analysis Focused on Romania

    Directory of Open Access Journals (Sweden)

    Raluca Mariana Grosu

    2013-08-01

    Full Text Available Migration represents one of the main means humans have chosen for improving their standards of living. Even though it is an important phenomenon manifested since ancient times, migration has never been so much in the attention of scholars and policy makers as it is in present times, especially for its implications in different areas such as demography, economy, sociology, politics, etc. As well, migration is a vital component of the contemporary society and in the same time plays a key role in the development of regions, from various perspectives such as economic, social, or cultural. Taking into consideration the previously outlined framework, the present paper aims at analyzing in a descriptive manner the international migration phenomenon in the European Union (EU countries between 2006 and 2010, in order to highlight the frame in which Romania is placed from the perspective of the quantitative dimension of international migration.

  17. Smoothing internal migration age profiles for comparative research

    Directory of Open Access Journals (Sweden)

    Aude Bernard

    2015-05-01

    Full Text Available Background: Age patterns are a key dimension to compare migration between countries and over time. Comparative metrics can be reliably computed only if data capture the underlying age distribution of migration. Model schedules, the prevailing smoothing method, fit a composite exponential function, but are sensitive to function selection and initial parameter setting. Although non-parametric alternatives exist, their performance is yet to be established. Objective: We compare cubic splines and kernel regressions against model schedules by assessingwhich method provides an accurate representation of the age profile and best performs on metrics for comparing aggregate age patterns. Methods: We use full population microdata for Chile to perform 1,000 Monte-Carlo simulations for nine sample sizes and two spatial scales. We use residual and graphic analysis to assess model performance on the age and intensity at which migration peaks and the evolution of migration age patterns. Results: Model schedules generate a better fit when (1 the expected distribution of the age profile is known a priori, (2 the pre-determined shape of the model schedule adequately describes the true age distribution, and (3 the component curves and initial parameter values can be correctly set. When any of these conditions is not met, kernel regressions and cubic splines offer more reliable alternatives. Conclusions: Smoothing models should be selected according to research aims, age profile characteristics, and sample size. Kernel regressions and cubic splines enable a precise representation of aggregate migration age profiles for most sample sizes, without requiring parameter setting or imposing a pre-determined distribution, and therefore facilitate objective comparison.

  18. CFD investigation of flow through internally riffled boiler tubes

    DEFF Research Database (Denmark)

    Rasmussen, Christian; Houbak, Niels; Sørensen, Jens Nørkær

    1997-01-01

    In this paper we show how to model the swirling flow in an internally riffled boiler tube. The flow field is visualized and the results are compared with measurements.......In this paper we show how to model the swirling flow in an internally riffled boiler tube. The flow field is visualized and the results are compared with measurements....

  19. Flow-accelerated corrosion 2016 international conference

    Science.gov (United States)

    Tomarov, G. V.; Shipkov, A. A.

    2017-05-01

    The paper discusses materials and results of the most representative world forum on the problems of flow-accelerated metal corrosion in power engineering—Flow-Accelerated Corrosion (FAC) 2016, the international conference, which was held in Lille (France) from May 23 through May 27, 2016, sponsored by EdF-DTG with the support of the International Atomic Energy Agency (IAEA) and the World Association of Nuclear Operators (WANO). The information on major themes of reports and materials of the exhibition arranged within the framework of the congress is presented. The statistics on operation time and intensity of FAC wall thinning of NPP pipelines and equipment in the world is set out. The paper describes typical examples of flow-accelerated corrosion damage of condensate-feed and wet-steam pipeline components of nuclear and thermal power plants that caused forced shutdowns or accidents. The importance of research projects on the problem of flow-accelerated metal corrosion of nuclear power units coordinated by the IAEA with the participation of leading experts in this field from around the world is considered. The reports presented at the conference considered issues of implementation of an FAC mechanism in single- and two-phase flows, the impact of hydrodynamic and water-chemical factors, the chemical composition of the metal, and other parameters on the intensity and location of FAC wall thinning localized areas in pipeline components and power equipment. Features and patterns of local and general FAC leading to local metal thinning and contamination of the working environment with ferriferous compounds are considered. Main trends of modern practices preventing FAC wear of NPP pipelines and equipment are defined. An increasing role of computer codes for the assessment and prediction of FAC rate, as well as software systems of support of the NPP personnel for the inspection planning and prevention of FAC wall thinning of equipment operating in singleand two

  20. U.S. internal migration and occupational attainment: Assessing absolute and relative outcomes by region and race.

    Science.gov (United States)

    Flippen, Chenoa

    2014-02-01

    This paper investigates the occupational implications of contemporary migration flows by region and race. Even though the expectation of a positive link between geographic and social mobility is a central tenet in the stratification literature, empirical assessments are rare and have produced inconsistent results. Our analysis departs from traditional frameworks by integrating both absolute and relative notions of occupational standing for evaluating migration outcomes, comparing migrants against non-migrant peers both at origin and destination. Results document that for whites migration is associated with higher occupational attainment both in absolute and relative terms, irrespective of the regional direction of the move. For blacks, on the other hand, absolute occupational gains are markedly absent for migration to the South, which is instead characterized by significant improvement in relative terms. The differences in absolute and relative gains by race and direction of the move helps contextualize the considerable black over representation in north-south migration and highlights the implications of current internal mobility for racial stratification.

  1. Selective internal migration. Does it explain Glasgow's worsening mortality record?

    Science.gov (United States)

    Popham, Frank; Boyle, Paul J; O'Reilly, Dermot; Leyland, Alastair H

    2011-11-01

    The mortality difference between Glasgow and the rest of Scotland has been increasing and mortality rates are higher than Glasgow's excess deprivation would suggest. One plausible explanation for this excess is selective migration. A sample of 137,073 individuals aged 15 to 64 in 1991 from the Scottish Longitudinal Study was used to test this explanation. Three geographic areas were compared: Glasgow; Aberdeen, Dundee and Edinburgh cities combined and the rest of Scotland. The impact of selective migration was assessed by calculating age and sex standardised mortality rates for 2001/03 by residence in 2001 and by residence in 1991. Glasgow experienced the greatest loss of population (-7.1%) between 1991 and 2001 but this was not strongly related to deprivation. It had the highest mortality at baseline and the difference between it and the other areas increased over the ten years. This pattern was not significantly affected by calculating death rates according to area of residence at 1991 or in 2001. Our results suggest that the increasing difference in mortality rates between Glasgow and the rest of Scotland over this period was probably not caused by selective migration. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. An integrative review of the role of remittances in international nurse migration

    Directory of Open Access Journals (Sweden)

    Squires A

    2014-12-01

    Full Text Available Allison Squires,1 Angela Amico2 1College of Nursing, 2Global Institute of Public Health, New York University, New York, NY, USA Abstract: This review seeks to understand the role of remittances in international nurse migration within the context of three theories of international migration: equilibrium approaches, social networks, and globalization. To analyze the phenomenon, an integrative review of the literature was conducted. Search terms sought articles discussing, either directly or indirectly, remittances and international nurse migration. The initial search returned 369 articles, and further screening decreased the total to 65. Full text screening reduced the final number for the analysis to 48. A directed content analysis structured the analytic approach by examining how authors discussed remittances in the content and context of the paper. The final analysis showed the majority of papers were policy analyses (five; opinion papers, reviews, or editorials that indirectly discussed remittances (27; or were qualitative and quantitative studies (16, either with primary data collection (14 or secondary data analyses (two. Overall, a nurse’s individual motivation for sending remittances home stemmed from familial factors but was never a primary driver of migration. Domestic labor market factors were more likely to drive nurses to migrate. The nurse’s country of origin also was a factor in the remittance dynamic. The identity of the author of the paper played a role in how they discussed remittances in the context of international nurse migration. The three theories of migration helped explain various aspects of the role of remittances in international nursing migration. While the phenomenon has changed since the 2008 global economic crisis and the passing of the World Health Organization’s Global Code of Practice on the International Recruitment of Health Personnel in 2010, future research around the role of remittances needs to

  3. Migration of Internal Pancreaticojejunostomy Stents into the Bile Ducts in Patients Undergoing Pancreatoduodenectomy.

    Science.gov (United States)

    Park, So Hyun; Kim, Jin Hee; Noh, Seung Yeon; Byun, Jae Ho; Lee, Seung Soo; Kim, Hyoung Jung; Park, Seong Ho; Lee, Sung Koo; Hwang, Dae Wook; Kim, Song Cheol; Han, Duck Jong; Lee, Moon-Gyu

    2015-11-01

    To investigate the incidence, complications, and risk factors of the migration of internal pancreaticojejunostomy (PJ) stents into the bile ducts in patients undergoing pancreatoduodenectomy. Postoperative computed tomography (CT) and clinical data of 802 patients with CT-detectable internal PJ stents were reviewed to assess the occurrence of stent migration into the bile ducts and stent-induced complications with their clinical significance. Risk factors for stent migration and stent-induced complications were determined. Stent migration into the bile ducts occurred in 135 patients (16.8 %); 40 of these (29.6 %) showed stent-induced complications including bile duct stricture, stone, and liver abscess. Clinically significant complications were identified in only eight patients. Neither the stent length nor diameter was associated with stent migration. A small stent diameter, peripheral location of the stent, absence of stent remigration from the bile ducts to the intestine, and longer stent retention time in the bile ducts were risk factors of stent-induced complications. The incidence of internal PJ stent migration into the bile ducts was 16.8 %. Migrated stents frequently caused complications, although they were mostly subclinical. Stent-induced complications were associated with stent diameter and location, stent remigration to the intestine, and stent retention time in the bile ducts.

  4. Internal migration and the health of the returned population: a nationally representative study of China.

    Science.gov (United States)

    Zhang, Luwen; Liu, Shuaishuai; Zhang, Guoying; Wu, Shaolong

    2015-07-28

    China had 236 million internal migrants in 2012 and the majority of them migrated from rural to urban areas. The research based on medical and epidemical records found that the migrants had worse health than the urban residents, but the household and working place investigations reported better health status. The sick or unhealthy migrants are likely to return to their hometowns, which in turn may cause a report bias or over-estimation of the health status of rural-to-urban migrants in China. This paper explores the association of migration status and the physical and psychological health of Chinese internal migrants. Nationally representative household survey data from the China Labor-force Dynamics Survey 2012 (CLDS) were used to analyze the association between the migration status and the health status of internal migrants in China. Migration status of the respondents was measured by hukou status and migration experience and all respondents were divided into four groups: returned population, migrant population, urban residents, and rural residents. Health status of respondents was measured by self-reported physical and psychological health. Migration experience was associated with the physical health of the returned population. The physical health of the returned population was worse than the migrant population and was distinguished by age and sex. The physical health status of migrant population was significantly better than rural residents, but not significantly better than urban residents. However, the association between migration status and psychological health was not statistically significant. Besides migration status, the socioeconomic status (SES) had a positive correlation with both physical and psychological health status, while occupational hazards exerted negative influence. The results indicate a tight association between migration experience and health status. The internal unhealthy migrants were more likely to return to their hometown and the

  5. Selection or network effects? Migration flows into 27 OECD countries, 1990-2000

    DEFF Research Database (Denmark)

    Pedersen, Peder J.; Pytlikova, Mariola; Smith, Nina

    patterns may be affected by the relatively generous welfare schemes in most OECD countries, but also network effects and migration policy changes may be important factors behind the observed development. This paper presents empirical evidence on immigration flows into 27 OECD countries during a period...... of 11 years, 1990- 2000. Using a panel data model, we analyze the determinants of the migration flows. Our results indicate that traditional factors as cultural and linguistic distance are important. Network effects are also strong, but vary between source and destination countries. We do not find clear......Recent migration patterns show growing migration pressure and changing composition of immigrants in many Western countries. During the latest decade, an increasing proportion of the OECD immigrants have been from poor countries, where the educational level of the population is low. The migration...

  6. Selection or Network Effects? Migration Flows into 27 OECD Countries, 1990-2000

    DEFF Research Database (Denmark)

    Pedersen, P.J.; Pytlikova, Mariola; Smith, Nina

    patterns may be affected by the relatively generous welfare schemes in most OECD countries, but also network effects and migration policy changes may be important factors behind the observed development. This paper presents empirical evidence on immigration flows into 27 OECD countries during a period...... of 11 years, 1990- 2000. Using a panel data model, we analyze the determinants of the migration flows. Our results indicate that traditional factors as cultural and linguistic distance are important. Network effects are also strong, but vary between source and destination countries. We do not find clear......Recent migration patterns show growing migration pressure and changing composition of immigrants in many Western countries. During the latest decade, an increasing proportion of the OECD immigrants have been from poor countries, where the educational level of the population is low. The migration...

  7. Selection or Network Effects? Migration Flows into 27 OECD Countries, 1990-2000

    DEFF Research Database (Denmark)

    Pedersen, P.J.; Pytlikova, Mariola; Smith, Nina

    patterns may be affected by the relatively generous welfare schemes in most OECD countries, but also network effects and migration policy changes may be important factors behind the observed development. This paper presents empirical evidence on immigration flows into 27 OECD countries during a period...... of 11 years, 1990-2000. Using a panel data model, we analyze the determinants of the migration flows. Our results indicate that traditional factors as cultural and linguistic distance are important. Network effects are also strong, but vary between source and destination countries. We do not find clear......Recent migration patterns show growing migration pressure and changing composition of immigrants in many Western countries. During the latest decade, an increasing proportion of the OECD immigrants have been from poor countries, where the educational level of the population is low. The migration...

  8. Lived Experiences of Indian International Students: Migration, Acculturation, and Resilience

    Science.gov (United States)

    Mukthyala, Suguna

    2013-01-01

    The student demographics in American universities have been changing in recent years and the result is a rapidly increasing enrollment of international students. In particular, the Indian international student population has grown to be the second largest, with over 100,000 students enrolling at post-secondary educational institutions across the…

  9. International migration and the global agenda: reflections on the 1998 UN Technical Symposium.

    Science.gov (United States)

    Castles, S

    1999-01-01

    This article reviews the nature of discussions at the 1998 UN Technical Symposium on International Migration and Development. The Symposium reviewed the literature linking migration and development and successful policy approaches. Several themes emerged. A research framework is needed for accounting for all types of population mobility at all stages of the migratory process. Research should integrate contributions from a range of disciplines. The influence of social networks and cultural capital has grown in importance. Strategies need to account for women's experiences, which involve both empowerment and exploitation. Strategies need to consider return migration and better public information on migration and settlement. It was agreed that there is a need for a variety of quantitative and qualitative approaches and multidimensional analysis. The links between migration and development are complex, but sufficient information is available to greatly improve policy formation and international cooperation. National level responses have occasionally eroded the rights and protection of migrants. Few countries have adopted the 1990 UN Convention on the Rights of Migrant Workers and their Families and ILO Conventions 97 and 143. A prominent realization was that international cooperation did matter. International migration should be viewed as an opportunity for cooperation and development.

  10. Exposure to international migration and its effect on childbearing in Turkey.

    Science.gov (United States)

    White, Kari; Buckley, Cynthia J

    2011-01-01

    International migration alters social norms, family structures, and population development in sending regions. Each of these factors affects fertility, making the impact of international migration on childbearing an increasingly important area of study. In many sending regions, the Demographic and Health Surveys (DHS) provide a promising, but underutilized, source of data for understanding the relationship between international migration and childbearing. Using the household and individual questionnaires in the 2003 Turkish DHS, we develop a multi-layered approach for measuring international migration. We then use these measures to examine differences in childbearing among women in migrant and non-migrant households, assessing the effects of migrant selection and migration-related roles and attitudes on the number of children born. After adjusting for selection characteristics, we find return female migrants and migrant wives are not significantly different from women in non-migrant households; role and attitude differences have only modest impacts on the association between women’s exposure to migration and childbearing.

  11. Visualizing breathing motion of internal cavities in concert with ligand migration in myoglobin.

    Science.gov (United States)

    Tomita, Ayana; Sato, Tokushi; Ichiyanagi, Kouhei; Nozawa, Shunsuke; Ichikawa, Hirohiko; Chollet, Matthieu; Kawai, Fumihiro; Park, Sam-Yong; Tsuduki, Takayuki; Yamato, Takahisa; Koshihara, Shin-Ya; Adachi, Shin-Ichi

    2009-02-24

    Proteins harbor a number of cavities of relatively small volume. Although these packing defects are associated with the thermodynamic instability of the proteins, the cavities also play specific roles in controlling protein functions, e.g., ligand migration and binding. This issue has been extensively studied in a well-known protein, myoglobin (Mb). Mb reversibly binds gas ligands at the heme site buried in the protein matrix and possesses several internal cavities in which ligand molecules can reside. It is still an open question as to how a ligand finds its migration pathways between the internal cavities. Here, we report on the dynamic and sequential structural deformation of internal cavities during the ligand migration process in Mb. Our method, the continuous illumination of native carbonmonoxy Mb crystals with pulsed laser at cryogenic temperatures, has revealed that the migration of the CO molecule into each cavity induces structural changes of the amino acid residues around the cavity, which results in the expansion of the cavity with a breathing motion. The sequential motion of the ligand and the cavity suggests a self-opening mechanism of the ligand migration channel arising by induced fit, which is further supported by computational geometry analysis by the Delaunay tessellation method. This result suggests a crucial role of the breathing motion of internal cavities as a general mechanism of ligand migration in a protein matrix.

  12. [Internal migration. Geographic mobility: search for well-being].

    Science.gov (United States)

    Corona Vazquez, R

    1988-01-01

    Interstate migrations have increased in the past 4 decades in Mexico. The number of Mexicans living in a state other than that of origin increased from slightly over 2 million in 1940 to 5 million in 1960 and 11.6 in 1980. The 558% in migrants exceeded the growth of national population of 342% in the same years. 10.7% of the residents of Mexico were migrants in 1940, 14.5% in 1960, and 17.5% in 1980. There were 89.6 male per 100 female migrants in 1940 and 92.4 males per 100 females in 1980. Most migrants are in the early working years. Among interstate migrants in 1979 for example, 43.5% were aged 15-29. Baja California Sur, Nuevo Leon, Tamaulipas, Morelos, and Quintana Roo are strong attractions for migrants, with positive annual net migration rates from 1940-80. The Federal District and State of Mexico have been the most important migrant destinations in recent decades because metropolitan Mexico city is located within their borders. Nevertheless, the Federal District lost more than 1/2 million inhabitants between 1970-80. The state of Mexico had negative annual net migration rates before the midcentury and positive rates thereafter. 10 Mexican states have usually been net expellers of population since 1940: Durango, Zacatecas, San Luis Potosi, Guanajuato, Hidalgo, Tlaxcala, Puebla, Michoacan, Guerrero, and Oaxaca. Together they account for slightly less than 1/2 of interstate outmigrants and receive about 10% of inmigrants. The proportion of the Mexican population living in these 10 states declined from 41.7% in 1940 to 29.6% in 1980. The principal destinations of outmigrants from the 10 states were the Federal District and the state of Mexico, which absorbed 45.5% in 1960 and 49.0% in 1980.

  13. Optimization of internal migration as a mechanism for solving the problems of monotowns in Sverdlovsk region

    Directory of Open Access Journals (Sweden)

    Evgeniya Vladimirovna Nekrasova

    2012-06-01

    Full Text Available The problems of single-industry towns and their solutions are reviewed in this paper. The analysis of internal mobility of the population of Russia on the basis of sociological research and Gallup International Research Institute of the family is made. The necessity of optimization of commuting between the territories of the municipal level to address the one-company towns is underlined. A mathematical model for the optimization of the problem of migration flows between the territories of the municipal level for commuting by road was developed. Testing was conducted on a model example of the six type-representative singleindustry towns of Sverdlovsk region (Revdinskiy district, VerkhnyayaPyshma, towns of Krasnoturinsk, Krasnouralsk, Serov and Sukhoi Log. Taking into account the current situation on the labor market and future labor requirements, a division of municipalities in the territory of employment and departure of migrants was performed under consideration. An optimal plan was constructed in areas of employment in company towns of Sverdlovsk region, which is designed to implement the scheme of traffic from the north to the south of Sverdlovsk region with the organization of interchange hub in the city of Yekaterinburg.

  14. International parental migration and the psychological well-being of children in Ghana, Nigeria, and Angola.

    Science.gov (United States)

    Mazzucato, Valentina; Cebotari, Victor; Veale, Angela; White, Allen; Grassi, Marzia; Vivet, Jeanne

    2015-05-01

    When parents migrate, leaving their children in the origin country, transnational families are formed. Transnational family studies on children who are "left behind" indicate that children suffer psychologically from parental migration. Many of the factors identified as affecting children's responses to parental migration however are not considered in child psychology and family sociology studies. This study aims to bridge these areas of knowledge by quantitatively investigating the association between transnational families and children's psychological well-being. It analyzes a survey conducted in three African countries in 2010-11 (Ghana N = 2760; Angola N = 2243; Nigeria N = 2168) amongst pupils of secondary schools. The study compares children in transnational families to those living with their parents in their country of origin. Children's psychological well-being is measured through the Strengths and Difficulties Questionnaire. Multiple regression analyses reveal that children in transnational families fare worse than their counterparts living with both parents but not in Ghana where living conditions mediate this relationship. This paper also looks at four characteristics of transnational families and finds that specific characteristics of transnational families and country contexts matter: (1) changing caregivers is associated with poorer well-being in all countries; (2) which parent migrates does not make a difference in Ghana, when mothers migrate and fathers are caregivers results in poorer well-being in Nigeria, and both mother's and father's migration result in worse outcomes in Angola; (3) the kin relationship of the caregiver is not associated with poorer well-being in Ghana and Nigeria but is in Angola; (4) children with parents who migrate internationally do not show different results than children whose parents migrate nationally in Ghana and Nigeria but in Angola international parental migration is associated with poorer psychological well

  15. Co-national and Transnational Networks in International Migration to Spain

    OpenAIRE

    Neubecker, Nina; Smolka, Marcel

    2012-01-01

    This paper provides evidence that transnational networks, defined as networks operating across nationalities, are shaping observed patterns of international migration. In a stylized model of migration with random friendship formation, individuals from a given origin country are attracted to destinations hosting large migrant communities from countries which are culturally and geographically close to their own origin country. In addition, the attracting force of a large community of co-nationa...

  16. Exploring multi-layer flow network of international trade based on flow distances

    CERN Document Server

    Shen, Bin; Zheng, Qiuhua

    2015-01-01

    Based on the approach of flow distances, the international trade flow system is studied from the perspective of multi-layer flow network. A model of multi-layer flow network is proposed for modelling and analyzing multiple types of flows in flow systems. Then, flow distances are introduced, and symmetric minimum flow distance is presented. Subsequently, we discuss the establishment of the multi-layer flow networks of international trade from two coupled viewpoints, i.e., the viewpoint of commodity flow and that of money flow. Thus, the multi-layer flow networks of international trade is explored. First, trading "trophic levels" are adopted to depict positions that economies occupied in the flow network. We find that the distributions of trading "trophic levels" have the similar clustering pattern for different types of commodity, and there are some regularities between money flow network and commodity flow network. Second, we find that active and competitive countries trade a wide spectrum of products, while ...

  17. International and return migration: the experience of Yemen.

    Science.gov (United States)

    1993-01-01

    "This study deals with the impact of...return migrants (or returnees) on the social and economic development of the Republic of Yemen in both the short and long terms, and assesses the possibility of their integration into the society and economy of the new Republic. The first section offers a brief history of Yemeni migration and description of the demographic and economic characteristics of the returnees compared with those of the non-migrant population. It also discusses the volume of remittances.... The second section...discusses the problems encountered in integrating [returnees] into the socio-economic fabric of the new State, the absorptive capacity of the various economic sectors, and the prospects for their employment in the short and medium run."

  18. The Landscape changes of the city of Shkodra as a consequence of Internal Migration

    Directory of Open Access Journals (Sweden)

    Bresena Kopliku

    2015-07-01

    Full Text Available Shkodra city landscape has changed dramatically after 1990. Not only the economic transition from a centralized to a free market economy and political change from totalitarism to democracy, but the whole Albanian society and landscape was transformed. Population movement displayed in all migration typologies- international migration, internal migration, recently return migration and circular movements - has played a significant role in changing the economy, social and cultural life, the environment and also the landscape. The analysis of the internal migration and its impact in the urban areas is the main objective of this paper. It tries to define the way that in-come movements have affected the urban landscape of the city of Shkodra in a way that can also be found in other urban areas of Albania. These movements were chaotic. Their main outcome was the creation of informal areas with new and quite big dwellings, based on the help of financial remittances coming from international migration. Despite the different intensity, their typologie has been almost the same in the main cities of the western coast of Albania. It resulted in the enlargement of suburban areas, occupation of agricultural land and industrial areas, changing of demographic structure, opening of new economic activities and in the creation of new social problems. These peripheral areas have changed during the transition period. Another objective of this paper includes the statistical data collected from in-depth interviews and participant observation based on the immigrants background, their movement experience and the way integration has affected the landscape. The article also argues that the city’s landcape cannot be understood without taking into consideration internal migration.

  19. NUMERICAL SIMULATION OF DROP MIGRATION IN CHANNEL FLOW UNDER ZERO-GRAVITY

    Institute of Scientific and Technical Information of China (English)

    LIU Tao; LU Xiyun

    2004-01-01

    The migration of deformable drops in the channel flow neglecting the gravity influence is investigated numerically by solving the incompressible Navier-Stokes equations using the finitedifference method coupled with the front-tracking technique. The objectives of this study are to examine the effectiveness of the present approach for predicting the migration of drops in a shear flow and to investigate the behavior of the drop migration in the channel flow under zero-gravity. To validate the present calculation, some typical results are compared with available computational and theoretical data, which confirms that the present approach is reliable in predicting the drop migration.With respect to the drop migration in the channel flow at finite Reynolds numbers, the drops either move to an equilibrium lateral position or undergo an oscillatory motion under different conditions.The effects of some typical parameters, e.g., the Reynolds number, the Weber number, the viscosity ratio and the density ratio of the drop fluid to the suspending medium, and the drop size, on the migration of drops are discussed and analyzed.

  20. Particle migration and sorting in microbubble streaming flows

    Science.gov (United States)

    Thameem, Raqeeb; Hilgenfeldt, Sascha

    2016-01-01

    Ultrasonic driving of semicylindrical microbubbles generates strong streaming flows that are robust over a wide range of driving frequencies. We show that in microchannels, these streaming flow patterns can be combined with Poiseuille flows to achieve two distinctive, highly tunable methods for size-sensitive sorting and trapping of particles much smaller than the bubble itself. This method allows higher throughput than typical passive sorting techniques, since it does not require the inclusion of device features on the order of the particle size. We propose a simple mechanism, based on channel and flow geometry, which reliably describes and predicts the sorting behavior observed in experiment. It is also shown that an asymptotic theory that incorporates the device geometry and superimposed channel flow accurately models key flow features such as peak speeds and particle trajectories, provided it is appropriately modified to account for 3D effects caused by the axial confinement of the bubble. PMID:26958103

  1. Particle migration and sorting in microbubble streaming flows.

    Science.gov (United States)

    Thameem, Raqeeb; Rallabandi, Bhargav; Hilgenfeldt, Sascha

    2016-01-01

    Ultrasonic driving of semicylindrical microbubbles generates strong streaming flows that are robust over a wide range of driving frequencies. We show that in microchannels, these streaming flow patterns can be combined with Poiseuille flows to achieve two distinctive, highly tunable methods for size-sensitive sorting and trapping of particles much smaller than the bubble itself. This method allows higher throughput than typical passive sorting techniques, since it does not require the inclusion of device features on the order of the particle size. We propose a simple mechanism, based on channel and flow geometry, which reliably describes and predicts the sorting behavior observed in experiment. It is also shown that an asymptotic theory that incorporates the device geometry and superimposed channel flow accurately models key flow features such as peak speeds and particle trajectories, provided it is appropriately modified to account for 3D effects caused by the axial confinement of the bubble.

  2. Migration to Risk Spectrum PSA Level 2 internal events

    Energy Technology Data Exchange (ETDEWEB)

    Crusells Girona, M.

    2012-07-01

    The paper is part of the APS model development level 2 internal events. According to the Spanish regulatory requirements and especially the recent safety instruction IS-25, Level 2 models are becoming increasingly important within the probabilistic safety analysis of the Spanish nuclear power plants, thus requiring accurate and efficient implementation such models, together with a systematic analysis thereof.

  3. Projected Population Size and Age Structure for Canada and Provinces: With and Without International Migration

    Directory of Open Access Journals (Sweden)

    Loh, Shirley

    2007-01-01

    Full Text Available EnglishThis paper examines the effect of net international migration on prospectivepopulation growth and age structure in Canada for the next 50 years. It alsoexamines the impact of international migration on provincial growth anddistribution. The procedure used in this study is by comparing two projectedpopulation scenarios, one with international migration and the other withoutinternational migration, based on the latest 2005-based population projections.The analysis of the scenarios shows that the assumed level of internationalmigration which is higher than the current level contributes to a continuousincrease in population over the next 50 years, but has limited effect to prevent oroffset the overall aging trend.FrenchCe document examine l’effet de la migration internationale sur la croissanceprospective de la population et la structure par âge au Canada pour les 50prochaines années. Il examine aussi l’impact de la migration internationale surla croissance et la distribution provinciales. La démarche utilisée dans cetteétude est de comparer les deux scénarios de population projetée l’un avecmigration internationale et l’autre sans migration internationale, selon lesdernières projections de population de 2005. L’analyse des scénarios démontreque le niveau présumé de migration internationale, plus élevé que le niveauactuel, contribue à une croissance continuelle de la population au cours des 50prochaines années, mais a peu d’effet quand à la prévention ou la tendance auvieillissement.

  4. Community Evolution in International Migration Top1 Networks.

    Science.gov (United States)

    Peres, Mihaela; Xu, Helian; Wu, Gang

    2016-01-01

    Focusing on each country's topmost destination/origin migration relation with other countries, this study builds top1 destination networks and top1 origin networks in order to understand their skeletal construction and community dynamics. Each top1 network covers approximately 50% of the complete migrant network stock for each decade between 1960 and 2000. We investigate the community structure by implementing the Girvan-Newman algorithm and compare the number of components and communities to illustrate their differences. We find that (i) both top1 networks (origin and destination) exhibited communities with a clear structure and a surprising evolution, although 80% edges persist between each decade; (ii) top1 destination networks focused on developed countries exhibiting shorter paths and preferring more advance countries, while top1 origin networks focused both on developed as well as more substantial developing nations that presented a longer path and more stable groups; (iii) only few countries have a decisive influence on community evolution of both top1 networks. USA took the leading position as a destination country in top1 destination networks, while China and India were the main Asian emigration countries in top1 origin networks; European countries and the Russian Federation played an important role in both.

  5. Community Evolution in International Migration Top1 Networks.

    Directory of Open Access Journals (Sweden)

    Mihaela Peres

    Full Text Available Focusing on each country's topmost destination/origin migration relation with other countries, this study builds top1 destination networks and top1 origin networks in order to understand their skeletal construction and community dynamics. Each top1 network covers approximately 50% of the complete migrant network stock for each decade between 1960 and 2000. We investigate the community structure by implementing the Girvan-Newman algorithm and compare the number of components and communities to illustrate their differences. We find that (i both top1 networks (origin and destination exhibited communities with a clear structure and a surprising evolution, although 80% edges persist between each decade; (ii top1 destination networks focused on developed countries exhibiting shorter paths and preferring more advance countries, while top1 origin networks focused both on developed as well as more substantial developing nations that presented a longer path and more stable groups; (iii only few countries have a decisive influence on community evolution of both top1 networks. USA took the leading position as a destination country in top1 destination networks, while China and India were the main Asian emigration countries in top1 origin networks; European countries and the Russian Federation played an important role in both.

  6. International labor migration and financial crisis in Korea.

    Science.gov (United States)

    Hyunho, S

    1999-06-01

    Although the Korean economy became severely depressed because of the financial crisis in November 1997, most foreign migrant workers in the country opted to stay rather than return to their home countries. This study examined the causes of their relative immobility at both the macro- and microlevel through the use of government statistics and survey data. The first section of this study explored in- and outflows of migrant workers in relation to labor market conditions and government interventions before and after the crisis. The second section looked into the effects of the crisis on the companies employing migrant workers, while the final section investigated the effects of the crisis on migrant workers. The findings of this study indicated that the amnesty measure, which was a major government policy to reduce the number of illegal sojourners, exerted some positive effect in the first months after the crisis. Employment and income opportunities at origin countries are important factors determining mobility. Moreover, manufacturing companies still prefer to hire migrant workers before native workers because of cheaper wages for the former. Overall, most migrant workers, regardless of their sojourn status, desire to stay in Korea because of two main reasons: 1) their total earnings are less than their migration costs; 2) they cannot get a job in their home country.

  7. Exploration of International Migration of Teachers in South Africa%南非教师国际流动探析

    Institute of Scientific and Technical Information of China (English)

    周志发

    2012-01-01

    在全球化时代,教师国际流动为南非教育发展带来了机遇和挑战。20世纪90年代,教师国际流动很大程度上缓解了南非国内教师的就业压力,但也导致其优质教育的流失。21世纪初,教师国际流动使得南非教师短缺现象更为严重。南非教师国际流动有“推力与拉力”双重因素。其动因主要包括“国际教师劳动力供求失衡、经济因素以及教育政策、政治和社会安全等非经济因素”。南非本土教师国际流动的对策关键在于政府能否掌握话语权,为教师国际流动制定必要的协议以保护自身的利益。以南非为首的非洲国家需要协调好全球化与民族主义之间的关系,从而达到利用全球化优化师资、教育理念与教育制度,并用爱国主义等方式吸引智力回流。%In the era of globalization, the international migration of teachers is great opportunities and chal lenges for the development of education in South Africa. In the 1990s, international teacher migration largely alle viated the pressure of domestic employment of teachers in South Africa, hut also resulted in the loss of quality ed ucation. At the beginning of the 21st century, the international flow of teachers made teacher shortage more serious in South Africa. International teacher migration in South African includes two factors : the influence of push and pull. The motivation mainly includes three factors: disequilibrium of international teachers' labor in supply and demand, salaries, as well as education policy, politics and social security and other non-economic factors. The key measure of local teacher migration in South Africa lies in the Government's ability to have the discourse fight in the field of international migration of teachers to make the necessary protocols in order to protect their own in- terests.

  8. Endothelial Myocyte Enhancer Factor 2c Inhibits Migration of Smooth Muscle Cells Through Fenestrations in the Internal Elastic Lamina.

    Science.gov (United States)

    Lu, Yao Wei; Lowery, Anthony M; Sun, Li-Yan; Singer, Harold A; Dai, Guohao; Adam, Alejandro P; Vincent, Peter A; Schwarz, John J

    2017-07-01

    Laminar flow activates myocyte enhancer factor 2 (MEF2) transcription factors in vitro to induce expression of atheroprotective genes in the endothelium. Here we sought to establish the role of Mef2c in the vascular endothelium in vivo. To study endothelial Mef2c, we generated endothelial-specific deletion of Mef2c using Tie2-Cre or Cdh5-Cre-ER(T2) and examined aortas and carotid arteries by en face immunofluorescence. We observed enhanced actin stress fiber formation in the Mef2c-deleted thoracic aortic endothelium (laminar flow region), similar to those observed in normal aortic inner curvature (disturbed flow region). Furthermore, Mef2c deletion resulted in the de novo formation of subendothelial intimal cells expressing markers of differentiated smooth muscle in the thoracic aortas and carotids. Lineage tracing showed that these cells were not of endothelial origin. To define early events in intimal development, we induced endothelial deletion of Mef2c and examined aortas at 4 and 12 weeks postinduction. The number of intimal cell clusters increased from 4 to 12 weeks, but the number of cells within a cluster peaked at 2 cells in both cases, suggesting ongoing migration but minimal proliferation. Moreover, we identified cells extending from the media through fenestrations in the internal elastic lamina into the intima, indicating transfenestral smooth muscle migration. Similar transfenestral migration was observed in wild-type carotid arteries ligated to induce neointimal formation. These results indicate that endothelial Mef2c regulates the endothelial actin cytoskeleton and inhibits smooth muscle cell migration into the intima. © 2017 American Heart Association, Inc.

  9. Were rivers flowing across the Sahara during the last interglacial? Implications for human migration through Africa.

    Science.gov (United States)

    Coulthard, Tom J; Ramirez, Jorge A; Barton, Nick; Rogerson, Mike; Brücher, Tim

    2013-01-01

    Human migration north through Africa is contentious. This paper uses a novel palaeohydrological and hydraulic modelling approach to test the hypothesis that under wetter climates c.100,000 years ago major river systems ran north across the Sahara to the Mediterranean, creating viable migration routes. We confirm that three of these now buried palaeo river systems could have been active at the key time of human migration across the Sahara. Unexpectedly, it is the most western of these three rivers, the Irharhar river, that represents the most likely route for human migration. The Irharhar river flows directly south to north, uniquely linking the mountain areas experiencing monsoon climates at these times to temperate Mediterranean environments where food and resources would have been abundant. The findings have major implications for our understanding of how humans migrated north through Africa, for the first time providing a quantitative perspective on the probabilities that these routes were viable for human habitation at these times.

  10. Magnetic Control of Lateral Migration of Ellipsoidal Microparticles in Microscale Flows

    Science.gov (United States)

    Zhou, Ran; Sobecki, Christopher A.; Zhang, Jie; Zhang, Yanzhi; Wang, Cheng

    2017-08-01

    Precise manipulations of nonspherical microparticles by shape have diverse applications in biology and biomedical engineering. Here, we study lateral migration of ellipsoidal paramagnetic microparticles in low-Reynolds-number flows under uniform magnetic fields. We show that magnetically induced torque alters the rotation dynamics of the particle and results in shape-dependent lateral migration. By adjusting the direction of the magnetic field, we demonstrate versatile control of the symmetric and asymmetric rotation of the particles, thereby controlling the direction of the particle's lateral migration. The particle rotations are experimentally measured, and their symmetry or asymmetry characteristics agree well with the prediction from a simple theory. The lateral migration mechanism is found to be valid for nonmagnetic particles suspended in a ferrofluid. Finally, we demonstrate shape-based sorting of microparticles by exploiting the proposed migration mechanism.

  11. Fluorescein thiocarbamyl amino acids as internal standards for migration time correction in capillary sieving electrophoresis.

    Science.gov (United States)

    Pugsley, Haley R; Swearingen, Kristian E; Dovichi, Norman J

    2009-04-10

    A number of algorithms have been developed to correct for migration time drift in capillary electrophoresis. Those algorithms require identification of common components in each run. However, not all components may be present or resolved in separations of complex samples, which can confound attempts for alignment. This paper reports the use of fluorescein thiocarbamyl derivatives of amino acids as internal standards for alignment of 3-(2-furoyl)quinoline-2-carboxaldehyde (FQ)-labeled proteins in capillary sieving electrophoresis. The fluorescein thiocarbamyl derivative of aspartic acid migrates before FQ-labeled proteins and the fluorescein thiocarbamyl derivative of arginine migrates after the FQ-labeled proteins. These compounds were used as internal standards to correct for variations in migration time over a two-week period in the separation of a cellular homogenate. The experimental conditions were deliberately manipulated by varying electric field and sample preparation conditions. Three components of the homogenate were used to evaluate the alignment efficiency. Before alignment, the average relative standard deviation in migration time for these components was 13.3%. After alignment, the average relative standard deviation in migration time for these components was reduced to 0.5%.

  12. Selection and network effects - Migration flows into OECD countries 1990-2000

    DEFF Research Database (Denmark)

    Pedersen, Peder J.; Pytlikova, Mariola; Smith, Nina

    2008-01-01

    This paper presents empirical evidence on immigration flows into the OECD countries during the period 1990-2000. Our results indicate that network effects are strong, but vary between different groups of welfare states and between countries according to the type of immigration policy being applie...... a major influence on the observed migration patterns until now. This may partly be explained by restrictive migration policies which may have dampened the potential selection effects....

  13. Migration of Air Flow in Non-Fixed Saturated Porous Medium

    Science.gov (United States)

    Kong, X.; Fritz, S.; Kinzelbach, W.

    2008-12-01

    Two phase flow in porous media is of importance in a number of processes relevant in environmental engineering. The study of gas movement following injection into liquid saturated porous media is an active area of exploration for theoretical and practical reasons, e.g., in air-sparging, oil recovery, and bio-filter. A set of two-dimensional laboratory visualization experiments reveals a previously unrecognized gas-flow instability in a liquid-saturated porous medium packed by its own weight. The medium is made of crushed fused silica glass and saturated with a glycerine-water solution for refractive-index-matching. The interaction of the air flow injected at the bottom and the matrix (porous medium) structure leads to mobilization of the matrix and an instability, which causes the air channel to migrate. The instability of air-channel migration differs significantly from the gas-flow instability in a fixed matrix described in previous research. The migration of the air channel appears as a sequence of former channels collapsing and new channels opening. This process is characterized by the reorganization of the matrix, and the switching between channelized flow and pulsating slug flow. The channel migration comes to a stop after some time, leaving one thin and stable channel. The process is studied by calculating the cumulated lateral movement distance of channel and the lateral width of the area affected by the migration. A dimensionless number is defined to describe the migration. It is observed to be a function of grain size, height of bed, and air flow rate.

  14. Three dimensional boundary layers in internal flows

    Science.gov (United States)

    Bodonyi, R. J.

    1987-01-01

    A numerical study of the effects of viscous-inviscid interactions in three-dimensional duct flows is presented. In particular interacting flows for which the oncoming flow is not fully-developed were considered. In this case there is a thin boundary layer still present upstream of the surface distortion, as opposed to the fully-developed pipe flow situation wherein the flow is viscous across the cross section.

  15. Stouffer's model of migration: a comparison of interstate and metropolitan flows.

    Science.gov (United States)

    Wadycki, W J

    1975-02-01

    The objectives of this paper are (1) to evaluate the accuracy of the intervening opportunities-competing migrants hypothesis (Stouffer, 1960) in estimating 1955-1960 interstate migration streams in the United States and (2) to compare the results with those obtained by Galle and Taeuber (1966) for metropolitan migration. Our results strongly confirm Stouffer's hypothesis and yield parameter estimates highly comparable to those obtained for metropolitan migration, except that competing migrants exert a stronger influence than intervening opportunities in interstate migration. Our study is based on 2,256 interstate migration flows in the continental United States, whereas Stouffer's intercity study and Galle and Taeuber's metropolitan study were each based on 116 migration flows. Our results indicate that Stouffer's theory holds for different levels of aggregation with remarkable consistency. Several theoretical models of the migration process are more compatible with Stouffer's original 1940 formulation of intervening opportunities than his 1960 reformulation. Estimates for interstate data indicate that the 1940 definition provides slightly better results. For both these reasons, it would seem that the 1940 formulation should be given serious consideration in future tests of Stouffer's hypothesis.

  16. The International Postal Network and Other Global Flows As Proxies for National Wellbeing

    CERN Document Server

    Hristova, Desislava; Anson, Jose; Luengo-Oroz, Miguel; Mascolo, Cecilia

    2016-01-01

    The digital exhaust left by flows of physical and digital commodities provides a rich measure of the nature, strength and significance of relationships between The digital exhaust left by flows of physical and digital commodities provides a rich measure of the nature, strength and significance of relationships between countries in the global network. With this work, we examine how these traces and the network structure can reveal the socioeconomic profile of different countries. We take into account multiple international networks of physical and digital flows, including the previously unexplored international postal network. By measuring the position of each country in the Trade, Postal, Migration, International Flights, IP and Digital Communications networks, we are able to build proxies for a number of crucial socioeconomic indicators such as GDP per capita and the Human Development Index ranking along with twelve other indicators used as benchmarks of national wellbeing by the United Nations and other int...

  17. New evidence on the effects of international migration on the risk of low birthweight in Mexico.

    Science.gov (United States)

    Sunil, Thankam S; Flores, Miguel; Garcia, Ginny E

    2012-04-01

    The purpose of this article is to provide new empirical evidence linking migration of Mexican households to the USA with infant health outcomes. By using new data for Mexico, the Encuesta Nacional de la Dinamica Demografica 2006, this research focuses on the effect of migration on birth weight. Multivariate logistic regression methods are used to model low birth weight (LBW) as a function of a set of proximate, intermediate and socioeconomic determinants. In analyzing the channels through which migration affects birth outcomes, the findings provide no conclusive evidence for remittances as the only mechanism associated with lowering the odds of LBW. Given the limitations of the data, the study results showed new empirical evidence explaining the significance of both financial and social remittances associated with international migration and infant health outcomes in Mexico.

  18. International migration in Western Europe: reflections on the past five years.

    Science.gov (United States)

    Bohning, W R

    1979-01-01

    Five significant developments have occurred since 1974 with regard to the European labor force: 1) growth of return migration; 2) adoption of a new ILO Convention and Recommendation on return migration; 3) the movement towards a New International Economic Order; 4) the holding of the World Employment Conference in 1976; and 5) growing support for the idea that countries of origin should be compensated for out-migration of its citizens. About 1.5-2 million migrant workers have returned to their country of origin since the early 1970's when about 6 million workers and dependents were in Western Europe. The inequity that pervades international economic relations in general and migration in particular stems from the unequal bargaining power of the partners and the absense of corrective international social policies. The developing countries' wish for a new economic order questions the distributional aspects of the old liberal order. While raw materials and trade are covered comprehensively, labor movement is neglected. The growing realization that migration is a resource drain has led many poor countries to request compensation.

  19. Internal wave-mediated shading causes frequent vertical migrations in fishes

    KAUST Repository

    Kaartvedt, Stein

    2012-04-25

    We provide evidence that internal waves cause frequent vertical migrations (FVM) in fishes. Acoustic data from the Benguela Current revealed that pelagic scattering layers of fish below ~140 m moved in opposite phases to internal waves, ascending ~20 m towards the wave trough and descending from the wave crest. At the trough, the downward displacement of upper waters and the upward migration of fish created an overlapping zone. Near-bottom fish correspondingly left the benthic boundary zone at the wave trough, ascending into an acoustic scattering layer likely consisting of zooplankton and then descending to the benthic boundary zone at the wave crest. We suggest that this vertical fish migration is a response to fluctuations in light intensity of 3 to 4 orders of magnitude caused by shading from a turbid surface layer that had chlorophyll a values of 3 to 4 mg m−3 and varied in thickness from ~15 to 50 m at a temporal scale corresponding to the internal wave period (30 min). This migration frequency thus is much higher than that of the common and widespread light-associated diel vertical migration. Vertical movements affect prey encounters, growth, and survival. We hypothesize that FVM increase the likelihood of prey encounters and the time for safe visual foraging among planktivorous fish, thereby contributing to efficient trophic transfer in major upwelling areas.

  20. Coil migration after endovascular coil occlusion of internal carotid artery pseudoaneurysms within the sphenoid sinus.

    Science.gov (United States)

    Struffert, T; Buhk, J H; Buchfelder, M; Rohde, V; Doerfler, A; Knauth, M

    2009-04-01

    We report two cases of coil migration after endovascular treatment of pseudoaneurysm of the internal carotid artery within the sphenoid sinus with coils and noncovered stents. Two patients underwent sphenoid sinus exposure for pituitary adenoma and chronic infection, respectively. As a complication pseudoaneurysms of the internal carotid artery within the sphenoid sinus developed. One patient was treated with stent and coils, the second with coils alone. Both patients experienced coil migration after 9 and 26 months, respectively, with the necessity for further treatment. Imaging was performed using flat detector computed tomography (FD-CT). Literature review revealed two additional cases of coil migration and four patients with the same treatment in stable condition. Pseudoaneurysms of the internal carotid artery are a special entity and the environment of the aneurysm within the sphenoid sinus may change over a long time. Coil embolization may lead to the late onset complication of coil migration with the possible risk of acute epistaxis. As a consequence, these patients need a careful and prolonged follow up. FD-CT is an appropriate technique to visualize the implanted coils and if present the migration of coil material.

  1. Internal flows of organism. Seitainai no nagare

    Energy Technology Data Exchange (ETDEWEB)

    Ryumae, S. (Tokyo Inst. of Technology, Tokyo (Japan). Faculty of Engineering)

    1993-08-15

    Introduction is given about features of flows in living things and about some flow phenomena that have been subjects of current researches, and methodological problems involved in the researches are explained. There are some different features of the flow in living things from those in artificial flow. The structural elements of the former flow (channels, fluid, flow change) vary in accordance with environment, activity state and health conditions. Explanation is given about features of the blood flow in the human body, with figures and a table of blood state on being pulsed out from the left cardiac, mean flow phases in the human systemic circulation, change of wave shapes of blood pressure, viscosity of blood, characteristics of vessel elasticity and collapsible flow, representative values of blood dynamics in each blood vessel. With regard to the respiratory system, features of air flow in human lung respiration are explained with figures of a branching model of air ways, a model of respiratory mechanism, relation between inner pressure and inner volume in the lung, total resistance of the air way in each branched generation, flow rate distribution formed by vibration flow and Pendelluft effect. Three problems in handling the flow in living things are pointed out, namely measurement of the state in living things as it is, by non-invasive means, analysis of phenomenon occuring in non-steady fluctuation and individual difference in the flow. 5 refs., 12 figs., 1 tab.

  2. Healthy or unhealthy migrants? Identifying internal migration effects on mortality in Africa using health and demographic surveillance systems of the INDEPTH network.

    Science.gov (United States)

    Ginsburg, Carren; Bocquier, Philippe; Béguy, Donatien; Afolabi, Sulaimon; Augusto, Orvalho; Derra, Karim; Herbst, Kobus; Lankoande, Bruno; Odhiambo, Frank; Otiende, Mark; Soura, Abdramane; Wamukoya, Marylene; Zabré, Pascal; White, Michael J; Collinson, Mark A

    2016-09-01

    Migration has been hypothesised to be selective on health but this healthy migrant hypothesis has generally been tested at destinations, and for only one type of flow, from deprived to better-off areas. The circulatory nature of migration is rarely accounted for. This study examines the relationship between different types of internal migration and adult mortality in Health and Demographic Surveillance System (HDSS) populations in West, East, and Southern Africa, and asks how the processes of selection, adaptation and propagation explain the migration-mortality relationship experienced in these contexts. The paper uses longitudinal data representing approximately 900 000 adults living in nine sub-Saharan African HDSS sites of the INDEPTH Network. Event History Analysis techniques are employed to examine the relationship between all-cause mortality and migration status, over periods ranging from 3 to 14 years for a total of nearly 4.5 million person-years. The study confirms the importance of migration in explaining variation in mortality, and the diversity of the migration-mortality relationship over a range of rural and urban local areas in the three African regions. The results confirm that the pattern of migration-mortality relationship is not exclusively explained by selection but also by propagation and adaptation. Consequences for public health policy are drawn.

  3. The effect of internal migration, individual and contextual characteristics on contraceptive use among Nigerian women.

    Science.gov (United States)

    Akinyemi, Joshua O; Odimegwu, Clifford O; Adebowale, Ayo S

    2017-06-23

    We investigated the relation of internal migration to contraceptive use and adjusted for individual and contextual (community) characteristics. Multilevel logistic regression models were fitted to nationally representative data of 28,876 women from 884 communities in Nigeria. Only about one out of every 10 women (10.4%) currently used a contraceptive method. Contraceptive prevalence according to the migration status were rural-urban (12.5%), urban-rural (13.8%), rural nonmigrants (6.2%) and urban nonmigrants (17.1%). The relationship between internal migration and contraceptive use was fully explained by individual and community characteristics. Programs aimed at increasing contraceptive prevalence should address contextual challenges alongside socioeconomic factors.

  4. LABOUR MARKET FLEXIBILITY IN TERMS OF INTERNAL MIGRATION

    Directory of Open Access Journals (Sweden)

    BUNEA DANIELA

    2010-07-01

    Full Text Available Modern economies have a high dynamics because of the rapid fluctuations of macroeconomic variables and parameters. Moreover, globalization emphasises the interdependencies among national economies, increasing their production capacities but, at the same time, making them more vulnerable to external perturbations. Shocks resulting from this turmoil can be absorbed depending on the degree of macromarket flexibility: goods market, labour market and money market. This flexibility becomes even more important for the member states of some optimal currency areas (OCA because it considers both the mobility of production factors and the symmetry of business cycle transmission; i.e. the correlation of macroeconomic policies. The authors of this paper intend to analyse the situation of the internal mobility of workers as a basis for labour market flexibility.

  5. On the role of high performance computing for simulating subsurface flow and chemical migration

    Energy Technology Data Exchange (ETDEWEB)

    Tompson, A.; Ashby, S.; Falgout, R.; Smith, S.

    1993-06-01

    The use of large-scale computing for simulating fluid flow and chemical migration in subsurface formations is reviewed. Increasingly, intensive, highly-resolved model calculations are being used experimentally to study the impacts of small-scale material heterogeneities on coupled flow and transport phenomena, and are becoming easier to carry out with advanced computing hardware. These issues are illustrated through an example problem focused on the calculation of steady fluid flow and chemical migration in a detailed, three-dimensional formation with synthetically-derived nonuniformities in material properties. Here the interest is in examining the coupled impacts on chemical mobility induced by nonuniform sorption reactions and heterogeneous flow fields. Ongoing activities are now emphasizing parallel computations for larger, dynamic, and nonlinear (two-phase) flow problems, improved interpretive methods for defining detailed material property distributions, as well as specific applications at real field sites.

  6. Bending the urban flow: a construction-migration strategy.

    Science.gov (United States)

    Shaw, R P

    1980-01-01

    The excess rate of migration to urban centers is a problem affecting over 50 developing countries and 18 developed ones (68% of the world's population). Policies that rely on compulsion or disincentives have mostly failed because they do not deal with the cause of the problem. This paper proposes a strategy of increasing or decreasing the rate of housing construction in different urban areas as a means of stimulating or reducing migration to those areas; in most developing areas priority is given to residential construction in already congested metropolitan areas. 5 assumptions are the basis for this approach: 1) migrants tend to gravitate to the most powerful growth poles; 2) residential construction is a leading sector of regional and urban economies; 3) the encouragement of construction activity will make itself felt indirectly via its effect on construction-related employment; 4) rates of residential construction may be manipulated through government policy affecting the cost of materials, availability of loans, level of unionization, and price of housing; and 5) residential construction is amenable to quick policy action. The central idea of the strategy is that an increase in residential construction will exercise a pull on migrants, increasing job opportunities, raising incomes, lowering housing costs, and improving the chances of home ownership. This idea has been verified by various projects in Hong Kong, Ghana, Venezuela, Brazil, Bahrain, Mexico, Colombia, Poland, USSR, and the UK. In Bahrain low-income housing programs have been used to relocate Bahraini nationals in new outlying suburbs and to promote population growth in rural villages. In Mexico self-help and low-income housing programs have helped to redirect migrants headed for small towns toward smaller communities. There is also evidence to show that building construction has the potential to expand and contribute to economic growth. Some problems of implementation might be finding an adequate

  7. Harmonization by simulation: a contribution to comparable international migration statistics in Europe

    NARCIS (Netherlands)

    Nowok, B.

    2010-01-01

    In today's globalized world, there is increasing demand for reliable and comparable statistics on international migration. This book contributes to a more profound understanding of the effect of definitional variations on the figures that are reported.The framework developed here for the harmonizati

  8. Rethinking International Migration of Human Capital and Brain Circulation: The Case of Chinese-Canadian Academics

    Science.gov (United States)

    Blachford, Dongyan Ru; Zhang, Bailing

    2014-01-01

    This article examines the dynamics of brain circulation through a historical review of the debates over international migration of human capital and a case study on Chinese-Canadian academics. Interviews with 22 Chinese-Canadian professors who originally came from China provide rich data regarding the possibilities and problems of the contemporary…

  9. Internal Migration and Depressive Symptoms among Migrant Factory Workers in Shenzhen, China

    Science.gov (United States)

    Mou, Jin; Cheng, Jinquan; Griffiths, Sian M.; Wong, Samuel Y. S.; Hillier, Sheila; Zhang, Dan

    2011-01-01

    There has been a dramatic increase in rural-urban migration in China over the last two decades but there are few studies on the mental health of Chinese internal migrants. This study assesses the prevalence of depressive symptoms (DS) and their associated factors among migrant factory workers in Shenzhen, China. A questionnaire survey was sent to…

  10. Rethinking International Migration of Human Capital and Brain Circulation: The Case of Chinese-Canadian Academics

    Science.gov (United States)

    Blachford, Dongyan Ru; Zhang, Bailing

    2014-01-01

    This article examines the dynamics of brain circulation through a historical review of the debates over international migration of human capital and a case study on Chinese-Canadian academics. Interviews with 22 Chinese-Canadian professors who originally came from China provide rich data regarding the possibilities and problems of the contemporary…

  11. What's wrong with the global migration of health care professionals? Individual rights and international justice.

    Science.gov (United States)

    Dwyer, James

    2007-01-01

    When health care workers migrate from poor countries to rich countries, they are exercising an important human right and helping rich countries fulfill obligations of social justice. They are also, however, creating problems of social justice in the countries they leave. Solving these problems requires balancing social needs against individual rights and studying the relationship of social justice to international justice.

  12. Health Workforce and International Migration: Can New Zealand Compete? OECD Health Working Papers No. 33

    Science.gov (United States)

    Zurn, Pascal; Dumont, Jean-Christophe

    2008-01-01

    This paper examines health workforce and migration policies in New Zealand, with a special focus on the international recruitment of doctors and nurses. The health workforce in New Zealand, as in all OECD countries, plays a central role in the health system. Nonetheless, maybe more than for any other OECD country, the health workforce in New…

  13. Migration of international students and mobilizing skills in the MENA Region

    NARCIS (Netherlands)

    Nour, S.

    2014-01-01

    This paper uses both the descriptive and comparative approaches to provide an overview of migration of international students from the Middle East and North Africa (MENA) region and mobilizing skills in the MENA Region. We fill the gap in the MENA literature and present a more comprehensive and

  14. Economic determinants of internal migration rates : A comparison across five European countries

    NARCIS (Netherlands)

    Van Der Gaag, Nicole; Van Wissen, Leo

    2008-01-01

    This paper addresses the issue of the relationship between internal migration rates at NUTS 2 level and economic developments. For five European countries, several hypotheses were tested on three groups of economic variables: general business cycle indicators, financial variables as well as

  15. Migration and self-esteem: A qualitative study among internal migrant girls in Turkey

    NARCIS (Netherlands)

    Altinyelken, H.K.

    2009-01-01

    This article examining the impact of migration experience on self-esteem of girls enrolled at primary schools in Turkey. It is based on a broader study that explored edueational and coping strategies of internal migrant girls living in a suburban town in the western part of Turkey. The study showed

  16. Economic determinants of internal migration rates: a comparison across five European countries

    NARCIS (Netherlands)

    van der Gaag, N.L.; van Wissen, L.J.G.

    2008-01-01

    This paper addresses the issue of the relationship between internal migration rates at NUTS 2 level and economic developments. For five European countries, several hypotheses were tested on three groups of economic variables: general business cycle indicators, financial variables as well as

  17. Internal Migration and Depressive Symptoms among Migrant Factory Workers in Shenzhen, China

    Science.gov (United States)

    Mou, Jin; Cheng, Jinquan; Griffiths, Sian M.; Wong, Samuel Y. S.; Hillier, Sheila; Zhang, Dan

    2011-01-01

    There has been a dramatic increase in rural-urban migration in China over the last two decades but there are few studies on the mental health of Chinese internal migrants. This study assesses the prevalence of depressive symptoms (DS) and their associated factors among migrant factory workers in Shenzhen, China. A questionnaire survey was sent to…

  18. Migration and self-esteem: A qualitative study among internal migrant girls in Turkey

    NARCIS (Netherlands)

    Altinyelken, H.K.

    2009-01-01

    This article examining the impact of migration experience on self-esteem of girls enrolled at primary schools in Turkey. It is based on a broader study that explored edueational and coping strategies of internal migrant girls living in a suburban town in the western part of Turkey. The study showed

  19. Step-Flow Growth on Vicinal GaAs Surfaces by Migration-Enhanced Epitaxy

    Science.gov (United States)

    Yamaguchi, Hiroshi; Horikoshi, Yoshiji

    1989-08-01

    The mechanism of step-flow growth on vicinal GaAs substrates during migration-enhanced epitaxy are studied using the reflection high-energy electron diffraction technique. Results show that the low As pressure during migration-enhanced epitaxy growth accelerates step-flow growth. In addition, it is also shown that monolayer terraces composed of surface Ga atoms are formed from step edges during the Ga deposition process. A GaAs/AlAs tilted superlattice is established using this growth technique. X-ray diffraction measurement and transmission electron microscopy observations show that the fabricated structure has periodic composition modulation along the axis tilted from the substrate azimuth.

  20. Are international fund flows pro- or counter-cyclical?

    NARCIS (Netherlands)

    Li, Suxiao; de Haan, Jakob; Scholtens, Bert; Yang, Haizhen

    2015-01-01

    We investigate whether international fund flows are pro-or counter-cyclical by employing a concordance index. International fund flows are investments in bond and equity markets by institutional investors, such as mutual funds, exchange traded funds, closed-end funds and hedge funds. We find that fu

  1. Effects of migration flows on the host country labour market following the 2004 EU enlargement

    Directory of Open Access Journals (Sweden)

    Peković Drinka

    2011-01-01

    Full Text Available This paper examines the effects of migration flows on unemployment, employment probabilities and native wages. The analysis contains the evaluation of migration effects of labour from Central and Eastern European countries which became European Union member states in 2004, on old member's labour market. Particular emphasis was placed on evidence of the migration flows impact from the new EU member states on the labour market performances in the United Kingdom and Ireland, the countries which did not restrict the access of new member immigrants to their labour markets. The analysis was realized for the period of 2004 to 2008 when the migration inflow was the largest. The empirical literature suggests that the migration effects on unemployment and employment probabilities of natives are very small. The young and low skilled native workers are more affected by migration flows than other groups of workers. Also, most empirical studies show small negative wage effects of immigration. Although the results of public researches and econometric studies have shown the modest potential labour migration flows from new member states and the small potential effects on EU-15 labour market, twelve out of fifteen old member states decided to apply transitional arrangements. The evidence presented in the report of the European Commission pointed out positive EU labour market impact of modest inflow of immigrants from new member states. Sectoral and skill composition of immigrants from new member states suggests their complementary role on EU labour market. The majority of immigrants from new member states are men, aged between 18 and 34, mediumlevel of education. Most immigrants have been employed in service sector, manufacturing and construction. The high employment rate of immigrants from new member states (78% and low unemployment rate (6% in the post-enlargement period have confirmed positive migration impact on EU labour market performances. The unemployment

  2. Sexual orientation, internal migration, and mental health during the transition to adulthood.

    Science.gov (United States)

    Ueno, Koji; Vaghela, Preeti; Ritter, Lacey J

    2014-12-01

    Previous research has suggested that sexual minorities may have higher rates of migration than heterosexuals, indicating their effort to escape stigma in the currently residing areas. However, direct evidence for the migration pattern has been lacking, and mental health implications of such coping effort have been unclear. This study seeks to fill these gaps in the literature by analyzing the Add Health data, which include longitudinal measures of residential locations, sexual orientation, and mental health. The analysis focuses on the transition to adulthood, when the rate of internal migration peaks. Among women, sexual minorities have a higher rate of migration than heterosexuals, but men do not show such a difference. Sexual minorities show better mental health when they migrate to counties with higher proportions of people living in urban areas whereas heterosexuals do not show such an association. Among sexual minority men, migration to counties with higher population density and higher proportions of college-educated residents is also linked to better mental health. © American Sociological Association 2014.

  3. Globalization, Development and International Migration: A Cross-National Analysis of Less-Developed Countries, 1970-2000

    Science.gov (United States)

    Sanderson, Matthew R.; Kentor, Jeffrey D.

    2009-01-01

    It is widely argued that globalization and economic development are associated with international migration. However, these relationships have not been tested empirically. We use a cross-national empirical analysis to assess the impact of global and national factors on international migration from less-developed countries. An interdisciplinary…

  4. Globalization, Development and International Migration: A Cross-National Analysis of Less-Developed Countries, 1970-2000

    Science.gov (United States)

    Sanderson, Matthew R.; Kentor, Jeffrey D.

    2009-01-01

    It is widely argued that globalization and economic development are associated with international migration. However, these relationships have not been tested empirically. We use a cross-national empirical analysis to assess the impact of global and national factors on international migration from less-developed countries. An interdisciplinary…

  5. Global migration topology analysis and modeling of bilateral flow network 2006-2010

    Science.gov (United States)

    Porat, I.; Benguigui, L.

    2016-07-01

    Migration is one of the most dramatic and vast human processes in modern times. Migration is defined as people that leave their home and home-land and move to a new country. In this research we address the pattern of this massive human movement with the tools of network theory. The undirected global flow migration network (2006-2010) was identified as an exclusive disassortative network which combines two types of defined groups of large- and small-degree (D) countries with betweeness (Be) of Be˜D 3. This structure was modeled and simulated with synthetic networks of similar characteristics as the global flow migration network, and the results suggest that small-degree nodes have the topology of random networks, but the dominant part of the large-degree hubs controls this topology and shapes the network into an ultra-small world. This exclusive topology and the difference of the global flow migration network from scale-free and from Erdös-Rényi networks may be a result of two defined and different topologies of large- and small-degree countries.

  6. Leading tip drives soma translocation via forward F-actin flow during neuronal migration.

    Science.gov (United States)

    He, Min; Zhang, Zheng-hong; Guan, Chen-bing; Xia, Di; Yuan, Xiao-bing

    2010-08-11

    Neuronal migration involves coordinated extension of the leading process and translocation of the soma, but the relative contribution of different subcellular regions, including the leading process and cell rear, in driving soma translocation remains unclear. By local manipulation of cytoskeletal components in restricted regions of cultured neurons, we examined the molecular machinery underlying the generation of traction force for soma translocation during neuronal migration. In actively migrating cerebellar granule cells in culture, a growth cone (GC)-like structure at the leading tip exhibits high dynamics, and severing the tip or disrupting its dynamics suppressed soma translocation within minutes. Soma translocation was also suppressed by local disruption of F-actin along the leading process but not at the soma, whereas disrupting microtubules along the leading process or at the soma accelerated soma translocation. Fluorescent speckle microscopy using GFP-alpha-actinin showed that a forward F-actin flow along the leading process correlated with and was required for soma translocation, and such F-actin flow depended on myosin II activity. In migrating neurons, myosin II activity was high at the leading tip but low at the soma, and increasing or decreasing this front-to-rear difference accelerated or impeded soma advance. Thus, the tip of the leading process actively pulls the soma forward during neuronal migration through a myosin II-dependent forward F-actin flow along the leading process.

  7. International medical graduates in the USA: a qualitative study on perceptions of physician migration.

    Science.gov (United States)

    Chen, P G; Nunez-Smith, M; Berg, D; Gozu, A; Rulisa, S; Curry, L A

    2011-01-01

    Objectives Physician migration from low-income to high-income nations is a global concern. Despite the centrality of understanding the perspectives of international medical graduates (IMGs) who have experienced migration to understanding the causes and consequences of this phenomenon, empirical literature is limited. The authors sought to characterise the experiences of IMGs from limited resource nations currently practicing primary care in the USA, with a focus on their perspectives on physician migration. Design The authors conducted a qualitative study utilising in-depth, in-person interviews and a standardised interview guide. The sample comprised a diverse, purposeful sample of IMGs (n=25) from limited resource nations (defined as having ≤2 physicians per 1000 population). Results Analyses revealed four recurrent and unifying themes reflecting the perspectives of IMGs in the USA on physician migration: (1) decisions to migrate were pragmatic decisions made in the context of individual circumstance; (2) the act of migration ultimately affected participants' ability to return home in multiple, unpredictable ways; (3) the ongoing process of acclimation was coupled with inherent conflicts surrounding the decision to remain in the USA; and (4) the effects of policies in both the home country and in the USA occurred at multiple levels. Conclusion The perspectives of IMGs who have migrated to the USA are an important addition to the ongoing discussion surrounding the global health workforce. Our findings highlight the effects of workforce policies which are often developed and discussed in abstraction, but have real, measurable impacts on the lives of individuals. Future efforts to address physician migration will need to acknowledge the immediate needs of the health workforce as well as the long-term needs of individuals within health systems.

  8. Empirical Evidence for Impacts of Internal Migration on Vegetation Dynamics in China from 1982 to 2000.

    Science.gov (United States)

    Song, Conghe; Lord, Jackson W; Zhou, Liming; Xiao, Jingfeng

    2008-08-27

    Migration is one of the major socio-economic characteristics of China since the country adopted the policy of economic reform in late 1970s. Many studies have been dedicated to understand why and how people move, and the consequences of their welfare. The purpose of this study is to investigate the environmental impacts of the large scale movement of population in China. We analyzed the trend in the Normalized Difference Vegetation Index (NDVI) from the Advanced Very High Resolution Radiometer (AVHRR) along with China migration data from the 1 percent national survey during 1982-1987, the 4(th) national census during 1985-1990 and the 5(th) national census during1995~2000. We found that the internal migration in China has a statistically significant negative impact on vegetation growth at the provincial scale from 1982 to 2000 even though the overall vegetation abundance increased in China. The impact from migration (R²=0.47, P=0.0001) on vegetation dynamics is the second strongest as among the factors considered, including changes in annual mean air temperature (R²=0.50, P=0.0001) and annual total precipitation (R²=0.30, P=0.0049) and gross domestic production (R²= 0.25, P=0.0102). The negative statistical relationship between the rate of increase in total migration and the change in vegetation abundance is stronger (R²=0.56, P=0.0000) after controlling for the effects of changes in temperature and precipitation. In-migration dominates the impacts of migration on vegetation dynamics. Therefore, it is important for policy makers in China to take the impacts of migration on vegetation growth into account while making policies aiming at sustainable humanenvironment relations.

  9. ELDERLY PARENTS AND INTERNATIONAL MIGRATION OF SONS: E VIDENCE FROM PAKISTA N AND AZAD JAMMU & KASHMIR

    Directory of Open Access Journals (Sweden)

    Asia ASHFAQ

    2016-05-01

    Full Text Available This paper aims to explore the relation between international migration of male children and the the parents left behind. The premise was to investigate how the international migration of male children affects the family and social life, financial security and health of the parents left behind. For this purpose, using qualitative research design In-Depth Interviews (IDI were conducted with four parents selected purposively whose male children had migrated abroad. Moreover, interview guide was used as research instrument for collecting the data and narrative analysis has been done to make sense of the data. Two cities namely Gujrat (Pakistan and Mirpur (Azad Jammu & Kashmir were selected on the basis of existing higher trend of international migration in these regions. The findings reveal that the respondents’ children were living abroad for more than 15 years and their children were involved in skilled labour work. The parents reported to have feelings of sadness, isolation, depression and loneliness in the absence of their children. The findings also unleashed the coping strategies used by left behind parents for lessening their suffering.

  10. International Migration and Gender Discrimination among Children Left Behind”

    Science.gov (United States)

    Antman, Francisca M.

    2012-01-01

    This paper considers how international migration of the head of household affects the allocation of resources toward boys relative to girls within households remaining in the home country. I address the endogeneity of migration with a differences-in-differences style regression model that compares those households in which migrants have already returned home with those in which migrants are still away. The evidence suggests that while the head of household is away a greater fraction of resources are spent on girls relative to boys, but upon his return, this pattern is reversed. PMID:23239896

  11. The Price of Rights: Regulating International Labor Migration (by Martin Ruhs, Princeton University Press, 2013

    Directory of Open Access Journals (Sweden)

    Susan Gzesh

    2014-03-01

    Full Text Available Migrant workers, particularly those classified as “low-skilled,” find that the denial of their rights is the “price of admission” to labor immigration programs. This is the global phenomenon described and analyzed by Martin Ruhs in The Price of Rights: Regulating International Labor Migration.  This book review provides an in-depth discussion of Ruhs’s comprehensive study of labor immigration policies and the substantial questions it raises for the global migration debate.  

  12. Impacts and Risks of Migration and Refugee Flows in Africa

    Science.gov (United States)

    2012-03-12

    mechanisms, perpetrators have been able to enter camps and commit sexual assaults against girls and women. Many cases of rape have not been...reported because of the associated shame , and there are few support services for victims (IRIN, 11 November 2011; Oxfam, 10 September 2010; CRIN, 13 August...displaced persons from returning home. For example, Somalia is the worst offender for refugees and internally displaced persons, economic decline, human

  13. Functional city zoning. Environmental assessment of eco-geological substance migration flows.

    Science.gov (United States)

    Dubrova, Stanislav V; Podlipskiy, Ivan I; Kurilenko, Vitaliy V; Siabato, Willington

    2015-02-01

    One of the unsolved problems today is that of the division of the natural (geochemical background) and anthropogenic components of substance migration flows, such as complex integrated systems in the supergene zone. Not only qualitative, but also quantitative assessment of each component allows greater understanding of the correlation between the processes within the geological body and their impact on the environment. This study is based on academic knowledge in the field of geological sciences and study group research-developments aimed at the detailed examination of the migration of pollutants in anthropogenically modified city soils and the creation of a methodological framework in the field of the geochemical zoning of substance migration flows in the hypergenesis zone. We demonstrate that certain parameters of "zero-level" pollutant concentration for functional area land use can be developed for each city - the state of the environment before the beginning of a new stage of technogenesis.

  14. On the Mutual Dynamics of Interregional Gross Migration Flows in Space and Time

    DEFF Research Database (Denmark)

    Mitze, Timo

    2016-01-01

    . Using a time-dynamic spatial Durbin model as preferred empirical specification, the results indicate that regional differences in real income growth, the labor participation rate and real-estate prices impact on interregional out-migration flows. The estimated coefficients signs of the obtained space...

  15. Selection or Network Effects? Migration Flows into 27 OECD Countries, 1990-2000

    DEFF Research Database (Denmark)

    Pedersen, P.J.; Pytlikova, Mariola; Smith, Nina

    of 11 years, 1990- 2000. Using a panel data model, we analyze the determinants of the migration flows. Our results indicate that traditional factors as cultural and linguistic distance are important. Network effects are also strong, but vary between source and destination countries. We do not find clear...

  16. Interntional Migration with Heterogeneous Agents: Theory and Evidence

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Brücker, Herbert

    Two puzzling facts of international migration are that only a small share of a sending country's population emigrates and that net migration rates tend to cease over time. This paper addresses these issues in a migration model with heterogeneous agents that features temporary migration....... In equilibrium a positive relation exists between the stock of migrants and the income differential, while the net migration flow becomes zero. Consequently, empirical migration models, estimating net migration flows instead of stocks, may be misspecified. This suspicion appears to be confirmed by our empirical...... investigation of cointegration relationships of flow and stock migration models....

  17. Interntional Migration with Heterogeneous Agents: Theory and Evidence

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Brücker, Herbert

    Two puzzling facts of international migration are that only a small share of a sending country's population emigrates and that net migration rates tend to cease over time. This paper addresses these issues in a migration model with heterogeneous agents that features temporary migration....... In equilibrium a positive relation exists between the stock of migrants and the income differential, while the net migration flow becomes zero. Consequently, empirical migration models, estimating net migration flows instead of stocks, may be misspecified. This suspicion appears to be confirmed by our empirical...... investigation of cointegration relationships of flow and stock migration models....

  18. The Impact of International Migration on the Labor Market – A Case Study from Hungary

    Directory of Open Access Journals (Sweden)

    Judit Oláh

    2017-08-01

    Full Text Available The economic, political and social changes experienced globally in recent years have influenced international migration in various countries. The aim of our study is to present the economic and non-economic aspects which determine the quantitative evaluation of migration and to reveal which of the two main factor groups is more dominant. In January 2017, an online questionnaire survey was conducted on the subject of migration. The group of respondents consisted of 438 full-time BSc, MSc and PhD students in Hungarian higher education institutions. Based on these questionnaires, two independent samples t-test, and one-way ANOVA, factor analysis and binary logistic regression procedures were performed. Based on the findings obtained, it was concluded that anti-migration behaviour cannot be explicitly explained by its economic impacts on the labour market. The rejecting attitudes observed on behalf of certain respondents were not in significant correlation with their highest educational levels or their given social class. As a result of the statistical analysis performed, it was concluded that the integration of foreigners is hindered by the so-called socio-cultural barriers, which cannot be removed solely by economic policy measures. Social conflicts of interest have to be eliminated in order for migration to have an active and permanently positive impact on the economy.

  19. Healthy migrant and salmon bias hypotheses: a study of health and internal migration in China.

    Science.gov (United States)

    Lu, Yao; Qin, Lijian

    2014-02-01

    The existing literature has often underscored the "healthy migrant" effect and the "salmon bias" in understanding the health of migrants. Nevertheless, direct evidence for these two hypotheses, particularly the "salmon bias," is limited. Using data from a national longitudinal survey conducted between 2003 and 2007 in China, we provide tests of these hypotheses in the case of internal migration in China. To examine the healthy migrant effect, we study how pre-migration self-reported health is associated with an individual's decision to migrate and the distance of migration. To test the salmon bias hypothesis, we compare the self-reported health of migrants who stay in destinations and who return or move closer to home villages. The results provide support for both hypotheses. Specifically, healthier individuals are more likely to migrate and to move further away from home. Among migrants, those with poorer health are more likely to return or to move closer to their origin communities. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Building Responsive Health Systems to Help Communities Affected by Migration: An International Delphi Consensus

    Science.gov (United States)

    Pottie, Kevin; Hui, Charles; Rahman, Prinon; Ingleby, David; Akl, Elie A.; Russell, Grant; Ling, Li; Wickramage, Kolitha; Mosca, Davide; Brindis, Claire D.

    2017-01-01

    Persons affected by migration require health systems that are responsive and adaptable to the needs of both disadvantaged migrants and non-migrant populations. The objective of this study is to support health systems for populations affected by migration. Materials and Methods: An international Delphi consensus process was used to identify policy approaches to improve health systems for populations affected by migration. Participants were leading migrant health experts from Americas, Europe, Middle East, Asia, and Australasia. We calculated average ranking scores and qualitatively analyzed open-ended questions. Results: Participants identified the following key areas as priorities for policy development: health inequities, system discrimination, migrant related health data, disadvantaged migrant sub-groups, and considerations for disadvantaged non-migrant populations. Highly ranked items to improve health systems were: Health Equity Impact Assessment, evidence based guidelines, and the International Organization for Migration annual reports. Discussion: Policy makers need tools, data and resources to address health systems challenges. Policies need to avoid preventable deaths of migrants and barriers to basic health services. PMID:28165380

  1. Internal Migration of Canadian Immigrants, 1993-2004: Evidence from the Survey of Labour and Income Dynamics

    Directory of Open Access Journals (Sweden)

    K. Bruce Newbold

    2011-01-01

    Full Text Available Combining the 1993, 1996, and 1999 six-year panels of the Survey of Labour and Income Dynamics Master Files, the purpose of the paper is twofold. First, it examines the migration and distribution patterns of the foreign-born across Census Metropolitan Areas (CMAs. Second, it examines how internal migration modeling results may differ whether pre- and post-migration measures are used. Results suggest that internal migration of the foreign-born generally does not increase their dispersion across Canada, with the foreign-born primarily choosing one of the three immigrant gateway cities of Toronto, Montreal and Vancouver, or moving to other relatively large CMAs.

  2. Cross-stream migration of a surfactant-laden deformable droplet in a Poiseuille flow

    Science.gov (United States)

    Das, Sayan; Mandal, Shubhadeep; Chakraborty, Suman

    2017-08-01

    The motion of a viscous deformable droplet suspended in an unbounded Poiseuille flow in the presence of bulk-insoluble surfactants is studied analytically. Assuming the convective transport of fluid to be negligible, we perform a small-deformation perturbation analysis to obtain the droplet migration velocity. The droplet dynamics strongly depends on the distribution of surfactants along the droplet interface, which is governed by the relative strength of convective transport of surfactants as compared with the diffusive transport of surfactants. The present study is focused on the following two limits: (i) when the surfactant transport is dominated by surface diffusion and (ii) when the surfactant transport is dominated by surface convection. In the first limiting case, it is seen that the axial velocity of the droplet decreases with an increase in the advection of the surfactants along the surface. The variation of cross-stream migration velocity, on the other hand, is analyzed over three different regimes based on the ratio of the viscosity of the droplet phase to that of the carrier phase (λ). In the first regime (˜λ migration velocity decreases with an increase in surface advection of the surfactants, although there is no change in the direction of droplet migration. For the second regime (˜0.75 migration of the droplet changes (which means the droplet moves either towards the flow centerline or away from it) depending on different parameters. In the third regime (˜λ > 11), the migration velocity is merely affected by any change in the surfactant distribution. For the other limit of higher surface advection in comparison with surface diffusion of the surfactants, the droplet always moves towards the flow centerline and the axial velocity of the droplet is found to be independent of the surfactant distribution. However, the cross-stream velocity is found to decrease with an increase in nonuniformity in surfactant distribution.

  3. Groundwater flow and tritium migration from the SRS Old Burial Ground to Fourmile Branch

    Energy Technology Data Exchange (ETDEWEB)

    Flach, G.P.; Hamm, L.L.; Harris, M.K. [and others

    1996-04-01

    The objectives of this investigation are twofold. The initial goal is to devise and demonstrate a technique for directly incorporating fine-scale lithologic data into heterogeneous hydraulic conductivity fields, for improved groundwater flow and contaminant transport model accuracy. The ultimate goal is to rigorously simulate past and future tritium migration from the SRS Old Burial Ground towards Fourmile Branch, to better understand the effects of various remediation alternatives such as no action and capping. Large-scale variability in hydraulic conductivity is usually the main influence on field-scale groundwater flow patterns and dispersive transport, following the relative locations of recharge and discharge areas. Incorporating realistic hydraulic conductivity heterogeneity into flow and transport models is paramount to accurate simulations, particularly for contaminant migration. Sediment lithologic descriptions and geophysical logs typically offer finer spatial resolution, and therefore more potential information about heterogeneity, than other site characterization data.

  4. Nurse migration and health workforce planning: Ireland as illustrative of international challenges.

    Science.gov (United States)

    Humphries, Niamh; Brugha, Ruairi; McGee, Hannah

    2012-09-01

    Ireland began actively recruiting nurses internationally in 2000. Between 2000 and 2010, 35% of new recruits into the health system were non-EU migrant nurses. Ireland is more heavily reliant upon international nurse recruitment than the UK, New Zealand or Australia. This paper draws on in-depth interviews (N=21) conducted in 2007 with non-EU migrant nurses working in Ireland, a quantitative survey of non-EU migrant nurses (N=337) conducted in 2009 and in-depth interviews conducted with key stakeholders (N=12) in late 2009/early 2010. Available primary and secondary data indicate a fresh challenge for health workforce planning in Ireland as immigration slows and nurses (both non-EU and Irish trained) consider emigration. Successful international nurse recruitment campaigns obviated the need for health workforce planning in the short-term, however the assumption that international nurse recruitment had 'solved' the nursing shortage was short-lived and the current presumption that nurse migration (both emigration and immigration) will always 'work' for Ireland over-plays the reliability of migration as a health workforce planning tool. This article analyses Ireland's experience of international nurse recruitment 2000-2010, providing a case study which is illustrative of health workforce planning challenges faced internationally.

  5. Global economic restructuring and international migration: some observations based on the Mexican and Central American experience.

    Science.gov (United States)

    Hamilton, N; Chinchilla, N S

    1996-01-01

    "The purpose of this article is to explore the relationship between processes of global economic restructuring and international migration through an examination of Mexican and Central American immigration to the U.S. and the experiences of Central American and Mexican immigrants in the U.S. This relationship is analysed as one of mutual causation: on the one hand, global restructuring affects conditions in both sending and receiving countries (it is not only a factor in emigration but also in the economic and political receptivity to immigrants at their point of destination); on the other, international migration in turn has an important impact on countries of origin, receiving countries, and the relationship between them." (SUMMARY IN FRE AND SPA) excerpt

  6. 5th International Conference on Jets, Wakes and Separated Flows

    CERN Document Server

    2016-01-01

    This volume collects various contributions from the 5th International Conference on Jets, Wakes and Separated Flows (ICJWSF2015) that took place in Stockholm during June 2015. Researchers from all around the world presented their latest results concerning fundamental and applied aspects of fluid dynamics. With its general character, the conference embraced many aspects of fluid dynamics, such as shear flows, multiphase flows and vortex flows, for instance. The structure of the present book reflects the variety of topics treated within the conference i.e. Jets, Wakes, Separated flows, Vehicle aerodynamics, Wall-bounded and confined flows, Noise, Turbomachinery flows, Multiphase and reacting flows, Vortex dynamics, Energy-related flows and a section dedicated to Numerical analyses.

  7. Fuel cell with internal flow control

    Science.gov (United States)

    Haltiner, Jr., Karl J.; Venkiteswaran, Arun [Karnataka, IN

    2012-06-12

    A fuel cell stack is provided with a plurality of fuel cell cassettes where each fuel cell cassette has a fuel cell with an anode and cathode. The fuel cell stack includes an anode supply chimney for supplying fuel to the anode of each fuel cell cassette, an anode return chimney for removing anode exhaust from the anode of each fuel cell cassette, a cathode supply chimney for supplying oxidant to the cathode of each fuel cell cassette, and a cathode return chimney for removing cathode exhaust from the cathode of each fuel cell cassette. A first fuel cell cassette includes a flow control member disposed between the anode supply chimney and the anode return chimney or between the cathode supply chimney and the cathode return chimney such that the flow control member provides a flow restriction different from at least one other fuel cell cassettes.

  8. Four essays in international trade: Trade flows in food products

    OpenAIRE

    Straume, Hans-Martin

    2015-01-01

    This thesis consists of four essays within the field of international trade economics, as well as an introduction chapter. All four papers are empirical studies of trade flows in food products using transaction data. The first chapter introduces the data used in the papers, and provides a brief review of the general literature. During the last decades, the focus in international economics has shifted from studies of trade flows using aggregated data to studies of firm behavior. Historic...

  9. Fluid-flow-induced mesenchymal stem cell migration: role of focal adhesion kinase and RhoA kinase sensors.

    Science.gov (United States)

    Riehl, Brandon D; Lee, Jeong Soon; Ha, Ligyeom; Lim, Jung Yul

    2015-03-01

    The study of mesenchymal stem cell (MSC) migration under flow conditions with investigation of the underlying molecular mechanism could lead to a better understanding and outcome in stem-cell-based cell therapy and regenerative medicine. We used peer-reviewed open source software to develop methods for efficiently and accurately tracking, measuring and processing cell migration as well as morphology. Using these tools, we investigated MSC migration under flow-induced shear and tested the molecular mechanism with stable knockdown of focal adhesion kinase (FAK) and RhoA kinase (ROCK). Under steady flow, MSCs migrated following the flow direction in a shear stress magnitude-dependent manner, as assessed by root mean square displacement and mean square displacement, motility coefficient and confinement ratio. Silencing FAK in MSCs suppressed morphology adaptation capability and reduced cellular motility for both static and flow conditions. Interestingly, ROCK silencing significantly increased migration tendency especially under flow. Blocking ROCK, which is known to reduce cytoskeletal tension, may lower the resistance to skeletal remodelling during the flow-induced migration. Our data thus propose a potentially differential role of focal adhesion and cytoskeletal tension signalling elements in MSC migration under flow shear.

  10. The Migration of Romanian Health Personnel and the Ethics of InternationalRecruitment

    Directory of Open Access Journals (Sweden)

    IRINA CEHAN

    2013-07-01

    Full Text Available In the last decade the phenomenon of international migration of healthcare personnel had increased, emphasizing the global crisis of workforce. In this context, the international recruitment of health personnel became a common practice for many states. In order to set some principles of an ethical recruitment, in 2010 the World Health Organization adopted The Global Code of Practice on the International Recruitment of Health Personnel. This was meant to be a reference tool for establishing and improving the necessary legal frame on the international recruitment of health personnel, but it did not defined the notion of ethical recruitment. This study is a qualitative one, based on interviews to highlight the concept of ethical recruitment in the opinion of representatives of foreign recruitment agencies which participated at fair jobs in Romania and of Romanian doctors who practice abroad.

  11. Migration and security : history, practice, and theory

    OpenAIRE

    Aslan, Nazlı Sinem

    2010-01-01

    Cataloged from PDF version of article. Receiving states viewed international migration as a means of economic development well until late 20th century. Since then policy makers around the world have increasingly associated migration to security and sought to meet this ‘threat’ through ‘control’. In the 21st century, the significance of international migration increased further as migration flows increased and took on new forms affecting the world as a whole. This thesis look...

  12. International labor migration in the social and economic development of Ukraine: trends, negative consequences and possible solutions

    Directory of Open Access Journals (Sweden)

    K.V. Shymanska

    2015-03-01

    Full Text Available The article describes the prerequisites for the development of labor migration in Ukraine. The main trends and negative consequences of international migration for Ukraine, including the growing problem of human trafficking, national aging, loss of fiscal revenues and increased strain on the pension fund have been defined. Statistics on labor migration indicators and the number of Ukrainian victims of trafficking in the world have been analyzed. In the conclusions possible solutions of overcoming social and economic problems associated with external labor migration, have been grounded, including monitoring internal and external migration data on its changes, signing international agreements on migrant workers’ abroad employment and social protection, improving higher education targeting to the needs of national and regional labor markets.

  13. Chagas disease at the crossroad of international migration and public health policies: why a national screening might not be enough.

    Science.gov (United States)

    Di Girolamo, C; Bodini, C; Marta, B L; Ciannameo, A; Cacciatore, F

    2011-09-15

    Since the year 2000, Chagas disease, traditionally known as a rural Latin American affliction, has been rising in the ranking of international health priorities due to the growing migration flows from endemic areas to non-endemic ones. Using the example of Italy and reporting preliminary results of a study carried out in the district of Bologna, the paper will argue that a disease-centred public health approach might be inadequate when dealing with complex and uncertain situations, in which complete statistical data are not available or not reliable, and in which the involved actors, health professionals on the one side, migrants on the other, appear to be unaware of the issue, or might even be denying it. In such a context, an effective public health approach should be capable of crossing disciplinary boundaries and bridging the gap between health services and communities, as well as between health and social issues.

  14. Computational methods for internal flows with emphasis on turbomachinery

    Science.gov (United States)

    Mcnally, W. D.; Sockol, P. M.

    1981-01-01

    Current computational methods for analyzing flows in turbomachinery and other related internal propulsion components are presented. The methods are divided into two classes. The inviscid methods deal specifically with turbomachinery applications. Viscous methods, deal with generalized duct flows as well as flows in turbomachinery passages. Inviscid methods are categorized into the potential, stream function, and Euler aproaches. Viscous methods are treated in terms of parabolic, partially parabolic, and elliptic procedures. Various grids used in association with these procedures are also discussed.

  15. Determinants of Mexico-U.S. Outward and Return Migration Flows: A State-Level Panel Data Analysis.

    Science.gov (United States)

    Chort, Isabelle; de la Rupelle, Maëlys

    2016-10-01

    Using a unique panel data set of state-to-state outward and return migration flows between Mexico and the United States from 1995 to 2012, this study is the first to analyze Mexico-U.S. migration at the state level and explore simultaneously the effect of economic, environmental, and social factors in Mexico over two decades. Pairing origin and destination states and controlling for a rich structure of fixed effects, we find that income positively impacts migration outflows, especially for Mexican states of origin with a recent migration history and for low-educated migrant flows, suggesting the existence of credit constraints. We find evidence that drought causes more out-migration, while other climatic shocks have no effect. Violence is found to increase out-migration flows from border states and to decrease migration from other Mexican states, especially where violence is directed at migrants. Last, return flows are larger when income growth at destination is lower, consistent with the accumulation of savings as a primary motivation of migrants. Exploring the impact of the crisis, we find evidence of significant changes in the geography of migration flows. Traditional flows are drying up, and new migration corridors are rising, with implications on the composition of the Mexican population in the United States. Although the effect of income on flows in both directions is unchanged by the crisis, the negative effect of violence on out-migration tends to reverse at the end of the period. Overall, this study emphasizes the interest of analyzing disaggregated flows at the infra-country level.

  16. Fluid migration in the subduction zone: a coupled fluid flow approach

    Science.gov (United States)

    Wang, Hongliang; Huismans, Ritske; Rondenay, Stéphane

    2016-04-01

    Subduction zone are the main entry point of water into earth's mantle and play an important role in the global water cycle. The progressive release of water by metamorphic dehydration induce important physical-chemical process in the subduction zone, such as hydrous melting, hydration and weakening of the mantle wedge, creation of pore fluid pressures that may weaken the subduction interface and induce earthquakes. Most previous studies on the role of fluids in subduction zones assume vertical migration or migration according to the dynamic pressure in the solid matrix without considering the pore fluid pressure effect on the deformation of the solid matrix. Here we investigate this interaction by explicitly modeling two-phase coupled poro-plastic flow during subduction. In this approach, the fluid migrates by compaction and decompaction of the solid matrix and affects the subduction dynamics through pore fluid pressure dependent frictional-plastic yield. Our preliminary results indicate that: 1) the rate of fluid migration depends strongly on the permeability and the bulk viscosity of the solid matrix, 2) fluid transfer occurs preferentially along the slab and then propagates into the mantle wedge by viscous compaction driven fluid flow, 3) fluid transport from the surface to depth is a prerequisite for producing high fluid pore pressures and associated hydration induced weakening of the subduction zone interface.

  17. Paternal Absence and International Migration: Stressors and Compensators Associated with the Mental Health of Mexican Teenagers of Rural Origin

    Science.gov (United States)

    Aguilera-Guzman, Rosa Maria; de Snyder, V. Nelly Salgado; Romero, Martha; Medina-Mora, Maria Elena

    2004-01-01

    Mexico-U.S. migration creates situations that may cause psychological distress. The purpose of this research project was to study the impact of father's physical absence due to international migration (FPAIM) on adolescent offspring of rural immigrants from Zacatecas, Mexico. Stressors and compensators were studied from the adolescent's…

  18. Russian periphery is dying in movement: A cohort assessment of Russian internal youth migration based on census data

    NARCIS (Netherlands)

    Kashnitsky, I.; Mkrtchyan, N.

    2014-01-01

    In this paper we study youth migration in Russia at the sub-regional level of administrative division. The aim of the research is to assess the volume of internal youth migration. The task is only doable with the use of census data, which not only allows us to research at the sub-regional level, but

  19. Direct Numerical Simulation of Particle Migration in a Simple Shear Flow

    Institute of Scientific and Technical Information of China (English)

    LV Hong; TANG Sheng-Li; ZHOU Wen-Ping

    2011-01-01

    @@ Motion of a rectangular particle in a two-dimensional vertical shear flow of Newtonian fluid and viscoelastic fluid with different parameters is studied using the finite element arbitrary Lagrangian-Eulerian domain method.The results show that the centerline of the channel is a stable equilibrium position for the neutrally buoyant rectangular particle in a vertical shear flow.Inertia causes the particle to migrate towards the centerline of the channel.In addition, a critical elasticity number exists.When the elasticity number is below the critical value,the rectangular particle migrates to the centerline; otherwise the centerline of the channel is apparently no longer a global attractor of trajectories of the particle.

  20. Surviving utopia: Energy, social capital, and international migration in Ixcan, Guatemala

    Science.gov (United States)

    Taylor, Matthew John

    Mounting peasant impoverishment in Guatemala comes face to face with growing ecological impoverishment. Abysmal living standards for Guatemala's majority results from highly skewed land distribution, rapid population growth, and a brutal civil war, which lasted almost four decades and laid waste to many rural communities and fields. In the face of such adversity, Guatemalans migrate to remaining forested frontiers and make longer journeys to North America in search of work. In an attempt to understand and improve natural resource use, especially firewood, I uncover how networks of social relations (social capital) and international migration influence livelihoods in agricultural communities along a forested frontier. I used both qualitative and quantitative methods to gather information about the lives of residents in four agricultural villages in Ixcan, Guatemala. The results from extended fieldwork illustrate how high levels of social capital can benefit the lives of rural residents. I argue that development programs can take advantage of existing high levels of social capital and take measures to create social capital where it is lacking to ensure the successful implementation of development programs. I also discuss firewood management in each community and demonstrate the disjuncture between local firewood use and national energy plans. Finally, I show how migrants and the money they send home from North America radically alter land use and land distribution in this part of rural Guatemala. My study reveals the need to examine the linkages between large-scale international migration, social capital, and the environment in communities that rely on the land for survival.

  1. Augmenting flows for the consistent migration of multi-commodity single-destination flows in SDNs

    DEFF Research Database (Denmark)

    Brandt, Sebastian; Förster, Klaus-Tycho; Wattenhofer, Roger

    2017-01-01

    Updating network flows in a real-world setting is a nascent research area, especially with the recent rise of Software Defined Networks. While augmenting s-t flows of a single commodity is a well-understood concept, we study updating flows in a multi-commodity setting: Given a directed network wi...

  2. Inertia-driven particle migration and mixing in a wall-bounded laminar suspension flow

    Energy Technology Data Exchange (ETDEWEB)

    Loisel, V.; Abbas, M., E-mail: micheline.abbas@ensiacet.fr; Masbernat, O. [Université de Toulouse INPT-UPS: Laboratoire de Génie Chimique and CNRS, Fédération de Recherche FERMaT, Toulouse (France); Climent, E. [Université de Toulouse INPT-UPS: Institut de Mécanique des Fluides de Toulouse and CNRS, Fédération de Recherche FERMaT, Toulouse (France)

    2015-12-15

    Laminar pressure-driven suspension flows are studied in the situation of neutrally buoyant particles at finite Reynolds number. The numerical method is validated for homogeneous particle distribution (no lateral migration across the channel): the increase of particle slip velocities and particle stress with inertia and concentration is in agreement with former works in the literature. In the case of a two-phase channel flow with freely moving particles, migration towards the channel walls due to the Segré-Silberberg effect is observed, leading to the development of a non-uniform concentration profile in the wall-normal direction (the concentration peaks in the wall region and tends towards zero in the channel core). The particle accumulation in the region of highest shear favors the shear-induced particle interactions and agitation, the profile of which appears to be correlated to the concentration profile. A 1D model predicting particle agitation, based on the kinetic theory of granular flows in the quenched state regime when Stokes number St = O(1) and from numerical simulations when St < 1, fails to reproduce the agitation profile in the wall normal direction. Instead, the existence of secondary flows is clearly evidenced by long time simulations. These are composed of a succession of contra-rotating structures, correlated with the development of concentration waves in the transverse direction. The mechanism proposed to explain the onset of this transverse instability is based on the development of a lift force induced by spanwise gradient of the axial velocity fluctuations. The establishment of the concentration profile in the wall-normal direction therefore results from the combination of the mean flow Segré-Silberberg induced migration, which tends to stratify the suspension and secondary flows which tend to mix the particles over the channel cross section.

  3. Influence of flow velocity and spatial heterogeneity on DNAPL migration in porous media: insights from laboratory experiments and numerical modelling

    Science.gov (United States)

    Zheng, Fei; Gao, Yanwei; Sun, Yuanyuan; Shi, Xiaoqing; Xu, Hongxia; Wu, Jichun

    2015-12-01

    Understanding the migration of dense non-aqueous phase liquids (DNAPLs) in complex subsurface systems is important for evaluating contamination source zones and designing remediation schemes after spill events. Six sandbox experiments were performed to explore the individual effect of flow velocity, and the combined effect of flow velocity and layered lenses on a DNAPL (PCE) migration in porous media. DNAPL saturation was measured using a light transmission system, and saturation distribution was quantified by spatial moments. The experimental results show that large flow velocity significantly promotes lateral and vertical migration of the low-viscosity DNAPL, while when layered lenses exist, the infiltration rate decreases and horizontal spread increases. Migration processes were numerically simulated, and the modelling results tested against experimental results. Furthermore, migration of DNAPLs with different viscosities was simulated to explore the combined effects of flow velocity and geological heterogeneity. Simulation results show that enhanced heterogeneity makes low-viscosity DNAPLs migrate along preferential pathways, resulting in irregular DNAPL morphology. Layered lenses combined with heterogeneity complicate the effect of flow velocity on the migration of low-viscosity DNAPLs by changing percolation paths. Results also demonstrate that flow velocity exhibits relatively little influence on the migration of medium/high-viscosity DNAPLs, which is predominantly controlled by viscosity and heterogeneity. Enhanced heterogeneity has a larger effect on migration behavior. Findings indicate that the migration paths and position of the source zone could change significantly, due to the combined effect of groundwater flow velocity and geological heterogeneity; thus, comprehensive hydrogeological investigation is needed to characterize the source zone.

  4. Human capital on the move: Education as a determinant of internal migration in selected INDEPTH surveillance populations in Africa

    National Research Council Canada - National Science Library

    Ginsburg, Carren; Beguy, Donatien; Augusto, Orvalho; Odhiambo, Frank; Soura, Abdramane; White, Michael J; Bocquier, Philippe; Afolabi, Sulaimon; Derra, Karim; Otiende, Mark; Zabre, Pascal; Collinson, Mark A

    2016-01-01

    BACKGROUND Education, as a key indicator of human capital, is considered one of the major determinants of internal migration, with previous studies suggesting that human capital accumulates in urban...

  5. International Migration, US Immigration Law and Civil Society: From the Pre-Colonial Era to the 113th Congress (Edited by Leonir Mario Chiarello and Donald Kerwin, Scalabrini International Migration Network, 2014

    Directory of Open Access Journals (Sweden)

    Breana George

    2014-09-01

    Full Text Available International Migration, US Immigration Law and Civil Society: From the Pre-Colonial Era to the 113th Congress, published by the Scalabrini International Migration Network in collaboration with the Center for Migration Studies of New York, offers an overview of immigration law and policy that contextualizes the present challenges in reaching policy consensus in the immigration debate. This book review highlights the debate on executive action in relation to a chapter on the evolution of US immigration laws by Charles Wheeler and a chapter on the role of civil society in immigration policymaking by Sara Campos. 

  6. Internally displaced "victims of armed conflict" in Colombia: the trajectory and trauma signature of forced migration.

    Science.gov (United States)

    Shultz, James M; Garfin, Dana Rose; Espinel, Zelde; Araya, Ricardo; Oquendo, Maria A; Wainberg, Milton L; Chaskel, Roberto; Gaviria, Silvia L; Ordóñez, Anna E; Espinola, Maria; Wilson, Fiona E; Muñoz García, Natalia; Gómez Ceballos, Angela Milena; Garcia-Barcena, Yanira; Verdeli, Helen; Neria, Yuval

    2014-10-01

    While conflict-induced forced migration is a global phenomenon, the situation in Colombia, South America, is distinctive. Colombia has ranked either first or second in the number of internally displaced persons for 10 years, a consequence of decades of armed conflict compounded by high prevalence of drug trafficking. The displacement trajectory for displaced persons in Colombia proceeds through a sequence of stages: (1) pre-expulsion threats and vulnerability, (2) expulsion, (3) migration, (4) initial adaptation to relocation, (5) protracted resettlement (the end point for most forced migrants), and, rarely, (6) return to the community of origin. Trauma signature analysis, an evidence-based method that elucidates the physical and psychological consequences associated with exposures to harm and loss during disasters and complex emergencies, was used to identify the psychological risk factors and potentially traumatic events experienced by conflict-displaced persons in Colombia, stratified across the phases of displacement. Trauma and loss are experienced differentially throughout the pathway of displacement.

  7. μ-PIV measurements of the ensemble flow fields surrounding a migrating semi-infinite bubble.

    Science.gov (United States)

    Yamaguchi, Eiichiro; Smith, Bradford J; Gaver, Donald P

    2009-08-01

    Microscale particle image velocimetry (μ-PIV) measurements of ensemble flow fields surrounding a steadily-migrating semi-infinite bubble through the novel adaptation of a computer controlled linear motor flow control system. The system was programmed to generate a square wave velocity input in order to produce accurate constant bubble propagation repeatedly and effectively through a fused glass capillary tube. We present a novel technique for re-positioning of the coordinate axis to the bubble tip frame of reference in each instantaneous field through the analysis of the sudden change of standard deviation of centerline velocity profiles across the bubble interface. Ensemble averages were then computed in this bubble tip frame of reference. Combined fluid systems of water/air, glycerol/air, and glycerol/Si-oil were used to investigate flows comparable to computational simulations described in Smith and Gaver (2008) and to past experimental observations of interfacial shape. Fluorescent particle images were also analyzed to measure the residual film thickness trailing behind the bubble. The flow fields and film thickness agree very well with the computational simulations as well as existing experimental and analytical results. Particle accumulation and migration associated with the flow patterns near the bubble tip after long experimental durations are discussed as potential sources of error in the experimental method.

  8. Exosome Adherence and Internalization by Hepatic Stellate Cells Triggers Sphingosine 1-Phosphate-dependent Migration.

    Science.gov (United States)

    Wang, Ruisi; Ding, Qian; Yaqoob, Usman; de Assuncao, Thiago M; Verma, Vikas K; Hirsova, Petra; Cao, Sheng; Mukhopadhyay, Debabrata; Huebert, Robert C; Shah, Vijay H

    2015-12-25

    Exosomes are cell-derived extracellular vesicles thought to promote intercellular communication by delivering specific content to target cells. The aim of this study was to determine whether endothelial cell (EC)-derived exosomes could regulate the phenotype of hepatic stellate cells (HSCs). Initial microarray studies showed that fibroblast growth factor 2 induced a 2.4-fold increase in mRNA levels of sphingosine kinase 1 (SK1). Exosomes derived from an SK1-overexpressing EC line increased HSC migration 3.2-fold. Migration was not conferred by the dominant negative SK1 exosome. Incubation of HSCs with exosomes was also associated with an 8.3-fold increase in phosphorylation of AKT and 2.5-fold increase in migration. Exosomes were found to express the matrix protein and integrin ligand fibronectin (FN) by Western blot analysis and transmission electron microscopy. Blockade of the FN-integrin interaction with a CD29 neutralizing antibody or the RGD peptide attenuated exosome-induced HSC AKT phosphorylation and migration. Inhibition of endocytosis with transfection of dynamin siRNA, the dominant negative dynamin GTPase construct Dyn2K44A, or the pharmacological inhibitor Dynasore significantly attenuated exosome-induced AKT phosphorylation. SK1 levels were increased in serum exosomes derived from mice with experimental liver fibrosis, and SK1 mRNA levels were up-regulated 2.5-fold in human liver cirrhosis patient samples. Finally, S1PR2 inhibition protected mice from CCl4-induced liver fibrosis. Therefore, EC-derived SK1-containing exosomes regulate HSC signaling and migration through FN-integrin-dependent exosome adherence and dynamin-dependent exosome internalization. These findings advance our understanding of EC/HSC cross-talk and identify exosomes as a potential target to attenuate pathobiology signals.

  9. Computation of Internal Fluid Flows in Channels Using the CFD Software Tool FlowVision

    CERN Document Server

    Kochevsky, A N

    2004-01-01

    The article describes the CFD software tool FlowVision (OOO "Tesis", Moscow). The model equations used for this research are the set of Reynolds and continuity equations and equations of the standard k - e turbulence model. The aim of the paper was testing of FlowVision by comparing the computational results for a number of simple internal channel fluid flows with known experimental data. The test cases are non-swirling and swirling flows in pipes and diffusers, flows in stationary and rotating bends. Satisfactory correspondence of results was obtained both for flow patterns and respective quantitative values.

  10. Cohort profile: internal migration in sub-Saharan Africa—The Migration and Health in Malawi (MHM) study

    Science.gov (United States)

    Anglewicz, Philip; VanLandingham, Mark; Manda-Taylor, Lucinda; Kohler, Hans-Peter

    2017-01-01

    Purpose The Migration and Health in Malawi (MHM) study focuses on a key challenge in migration research: although it has long been established that migration and health are closely linked, identifying the effect of migration on various health outcomes is complicated by methodological challenges. The MHM study uses a longitudinal panel premigration and postmigration study design (with a non-migrant comparison group) to measure and/or control for important characteristics that affect both migration and health outcomes. Participants Data are available for two waves. The MHM interviewed 398 of 715 migrants in 2007 (55.7%) and 722 of 1013 in 2013 (71.3%); as well as 604 of 751 (80.4%) for a non-migrant reference group in 2013. The total interviewed sample size for the MHM in both waves is 1809. These data include extensive information on lifetime migration, socioeconomic and demographic characteristics, sexual behaviours, marriage, household/family structure, social networks and social capital, HIV/AIDS biomarkers and other dimensions of health. Findings to date Our result for the relationship between migration and health differs by health measure and analytic approach. Migrants in Malawi have a significantly higher HIV prevalence than non-migrants, which is primarily due to the selection of HIV-positive individuals into migration. We find evidence for health selection; physically healthier men and women are more likely to move, partly because migration selects younger individuals. However, we do not find differences in physical or mental health between migrants and non-migrants after moving. Future plans We are preparing a third round of data collection for these (and any new) migrants, which will take place in 2018. This cohort will be used to examine the effect of migration on various health measures and behaviours, including general mental and physical health, smoking and alcohol use, access to and use of health services and use of antiretroviral therapy. PMID

  11. Three musketeers: A dynamic model of capital inflow (FDI), the real wage rate and the net migration flow with empirical application

    OpenAIRE

    Peter Simmons; Yuanyuan Xie

    2013-01-01

    This paper develops a time continuous dynamic model of a system of piecewise differential equations to study the simultaneous interactions between capital flows (FDI), the real wage rate and the net migration flow allowing for immigration, return migration and immobility. Theoretically, we claim three contributions: this paper is the first one to recognize the inherent regime shifts in migration due to fixed migration costs, the chance of getting a job and two way migration; for non-zero movi...

  12. Flow induced particle migration in fresh concrete: Theoretical frame, numerical simulations and experimental results on model fluids

    DEFF Research Database (Denmark)

    Spangenberg, J.; Roussel, N.; Hattel, J.H.;

    2012-01-01

    In this paper, we describe and compare the various physical phenomena which potentially lead to flow induced particle migration in concrete. We show that, in the case of industrial casting of concrete, gravity induced particle migration dominates all other potential sources of heterogeneities ind...

  13. THEORETICAL ASPECT OF INTERNATIONAL COMMODITY & LOGISTIC FLOW MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Ishkhanov A. V.

    2015-10-01

    Full Text Available The reasons for the transformation of logistics systems of international trading companies are becoming the processes of integration of national economies into the world economy now, which contribute to the expansion of trading companies at the expense of the foreign markets development. In this regard, especially updated become theoretical developments in the field of commodity flows on an international caliber. The article analyzes the interpretations of scholars of various economic scientists of the concept of "commodity flow" explores theoretical approaches for building goods distribution management at the level of international companies. Particular attention is paid to the risks assessment in the process of changing the output of trading companies at the international level. The role of the international net brokers is determining in the logistic system of goods distribution. The front most methods of risk management of major trade companies are highly investigating. The authors conclude that in entering the international markets trading companies are often unable to develop an effective risk management system due to lack of information, difficulty adapting to the new business environment. Many aspects of international goods distribution require further study with the aim of improving the efficiency of inventory management and logistics network trade flows of businesses

  14. School-Age Children Obesity in Rural Communities with International Migration in Central Mexico.

    OpenAIRE

    Carmona González, Maricela; Viczcarra Bordi., Ivonne

    2009-01-01

    The objective of the study was to evaluate the prevalence of obesity in school children between 6 and 12 years old. The study was carried out in communities with international migration tradition in the south of the Mexico state. Changes on food habits and life style were also evaluated. The Index of Corporal Mass (ICM) of 276 students was recorded. The 276 students were divided into two groups according to migrant or non-migrant father and by gender to identify differences between groups. Pa...

  15. International migration, economic policy and human capital accumulation: a simulation study.

    Science.gov (United States)

    Van Dalen, H P

    1993-10-01

    "This paper examines the economic policy implications of international migration and human capital accumulation within a dynamic general equilibrium model. Each country produces by means of physical and human capital of two types (skilled and unskilled labour). Along optimal growth paths in a world of diverging population growth rates immigration can only be beneficial when the free rider effect (i.e., not paying for training costs) exceeds the capital dilution effect of an increase in population growth. Under quite general conditions the optimal immigration rate is zero."

  16. Parallel genetic algorithms with migration for the hybrid flow shop scheduling problem

    Directory of Open Access Journals (Sweden)

    K. Belkadi

    2006-01-01

    Full Text Available This paper addresses scheduling problems in hybrid flow shop-like systems with a migration parallel genetic algorithm (PGA_MIG. This parallel genetic algorithm model allows genetic diversity by the application of selection and reproduction mechanisms nearer to nature. The space structure of the population is modified by dividing it into disjoined subpopulations. From time to time, individuals are exchanged between the different subpopulations (migration. Influence of parameters and dedicated strategies are studied. These parameters are the number of independent subpopulations, the interconnection topology between subpopulations, the choice/replacement strategy of the migrant individuals, and the migration frequency. A comparison between the sequential and parallel version of genetic algorithm (GA is provided. This comparison relates to the quality of the solution and the execution time of the two versions. The efficiency of the parallel model highly depends on the parameters and especially on the migration frequency. In the same way this parallel model gives a significant improvement of computational time if it is implemented on a parallel architecture which offers an acceptable number of processors (as many processors as subpopulations.

  17. The International Postal Network and Other Global Flows as Proxies for National Wellbeing.

    Science.gov (United States)

    Hristova, Desislava; Rutherford, Alex; Anson, Jose; Luengo-Oroz, Miguel; Mascolo, Cecilia

    2016-01-01

    The digital exhaust left by flows of physical and digital commodities provides a rich measure of the nature, strength and significance of relationships between countries in the global network. With this work, we examine how these traces and the network structure can reveal the socioeconomic profile of different countries. We take into account multiple international networks of physical and digital flows, including the previously unexplored international postal network. By measuring the position of each country in the Trade, Postal, Migration, International Flights, IP and Digital Communications networks, we are able to build proxies for a number of crucial socioeconomic indicators such as GDP per capita and the Human Development Index ranking along with twelve other indicators used as benchmarks of national well-being by the United Nations and other international organisations. In this context, we have also proposed and evaluated a global connectivity degree measure applying multiplex theory across the six networks that accounts for the strength of relationships between countries. We conclude by showing how countries with shared community membership over multiple networks have similar socioeconomic profiles. Combining multiple flow data sources can help understand the forces which drive economic activity on a global level. Such an ability to infer proxy indicators in a context of incomplete information is extremely timely in light of recent discussions on measurement of indicators relevant to the Sustainable Development Goals.

  18. Polymer Stress-Gradient Induced Migration in Thin Film Flow Over Topography

    Science.gov (United States)

    Tsouka, Sophia; Dimakopoulos, Yiannis; Tsamopoulos, John

    2014-11-01

    We consider the 2D, steady film flow of a dilute polymer solution over a periodic topography. We examine how the distribution of polymer in the planarization of topographical features is affected by flow intensity and physical properties. The thermodynamically acceptable, Mavrantzas-Beris two-fluid Hamiltonian model is used for polymer migration. The resulting system of differential equations is solved via the mixed FE method combined with an elliptic grid generation scheme. We present numerical results for polymer concentration, stress, velocity and flux of components as a function of the non-dimensional parameters of the problem (Deborah, Peclet, Reynolds and Capillary numbers, ratio of solvent viscosity to total liquid viscosity and geometric features of the topography). Polymer migration to the free surface is enhanced when the cavity gets steeper and deeper. This increases the spatial extent of the polymer depletion layer and induces strong banding in the stresses away from the substrate wall, especially in low polymer concentration. Macromolecules with longer relaxation times are predicted to migrate towards the free surface more easily, while high surface tension combined with a certain range of Reynolds numbers affects the free surface deformations. Work supported by the General Secretariat of Research & Technology of Greece through the program ``Excellence'' (Grant No. 1918) in the framework ``Education and Lifelong Learning'' co-funded by the ESF.

  19. International Trade Modelling Using Open Flow Networks: A Flow-Distance Based Analysis.

    Science.gov (United States)

    Shen, Bin; Zhang, Jiang; Li, Yixiao; Zheng, Qiuhua; Li, Xingsen

    2015-01-01

    This paper models and analyzes international trade flows using open flow networks (OFNs) with the approaches of flow distances, which provide a novel perspective and effective tools for the study of international trade. We discuss the establishment of OFNs of international trade from two coupled viewpoints: the viewpoint of trading commodity flow and that of money flow. Based on the novel model with flow distance approaches, meaningful insights are gained. First, by introducing the concepts of trade trophic levels and niches, countries' roles and positions in the global supply chains (or value-added chains) can be evaluated quantitatively. We find that the distributions of trading "trophic levels" have the similar clustering pattern for different types of commodities, and summarize some regularities between money flow and commodity flow viewpoints. Second, we find that active and competitive countries trade a wide spectrum of products, while inactive and underdeveloped countries trade a limited variety of products. Besides, some abnormal countries import many types of goods, which the vast majority of countries do not need to import. Third, harmonic node centrality is proposed and we find the phenomenon of centrality stratification. All the results illustrate the usefulness of the model of OFNs with its network approaches for investigating international trade flows.

  20. STATE AID AND PARTICIPATION TO INTERNATIONAL TRADE FLOWS. ROMANIAS CASE

    Directory of Open Access Journals (Sweden)

    Pavel Elena Mihaela

    2010-12-01

    Full Text Available This article focuses on the Romanian state aid and participation to the international trade flows. The purpose of this research was to determine whether the state aid offered takes into account the evolution and the requirements of the new market conditions generated by the economic and financial crisis. Our main conclusion was that regarding Romanias participation to the international trade flows, as the state aid measures focused mainly on sectors with high social impact, trade came second on the governments concern.

  1. Internal characteristics of refractive-index matched debris flows

    Science.gov (United States)

    Gollin, Devis; Bowman, Elisabeth; Sanvitale, Nicoletta

    2016-04-01

    Debris flows are channelized masses of granular material saturated with water that travel at high speeds downslope. Their destructive character represents a hazard to lives and properties, especially in regions of high relief and runoff. The characteristics that distinguish their heterogeneous, multi-phase, nature are numerous: non-uniform surge formation, particle size ranging from clay to boulders, flow segregation with larger particles concentrating at the flow front and fluid at the tail making the composition and volume of the bulk varying with time and space. These aspects render these events very difficult to characterise and predict, in particular in the area of the deposit spread or runout - zones which are generally of most interest in terms of human risk. At present, considerable gaps exist in our understanding of the flow dynamics of debris flows, which originates from their complex motion and relatively poor observations available. Flume studies offer the potential to examine in detail the behaviour of model debris flows, however, the opaque nature of these flows is a major obstacle in gaining insight of their internal behaviour. Measurements taken at the sidewalls may be poorly representative leading to incomplete or misleading results. To probe internally to the bulk of the flow, alternative, nonintrusive techniques can be used, enabling, for instance, velocities and solid concentrations within the flowing material to be determined. We present experimental investigations into polydisperse granular flows of spherical immersed particles down an inclined flume, with specific attention directed to their internal behavior. To this end, the refractive indices of solids and liquid are closely matched allowing the two phases to be distinguished. Measurements are then made internally at a point in the channel via Plane Laser Induced Fluorescence, Particle Tracking Velocimetry, PTV and Particle Image Velocimetry, PIV. The objective is to to increase our

  2. Migration and religious (intolerance: Contribution to the studies regarding the impact of international migration and the perception of religious diversity

    Directory of Open Access Journals (Sweden)

    Olga Odgers Ortiz

    2005-07-01

    Full Text Available Mexicans migrating to the United Status confront a very different social space which forces them to re-elaborate multiple identity references, among which religious beliefs and practices stand out. A number of studies have shown that among those who migrate, some on occasion turn to practices of popular religiosity in order to create bridges and maintain links with their communities of origin, in other cases, the migratory experience favors the processes of religious conversion. The subject is reopened in this article in order to bring up a third expression of the impact of migration on religious conversion: the transformation of the idea of religious diversity among those who migrate and consequently, the modification of some attitudes of religious tolerance and intolerance.

  3. Linking international student mobility to skilled migration: the case of Denmark

    DEFF Research Database (Denmark)

    Mosneaga, Ana

    2010-01-01

    agenda for solidifying the country’s position as a knowledge society. Looking at the Danish case, this paper illustrates the policy areas as well as the central issues that come to the fore when a host country seeks to link international student mobility and skilled migration. The discussion provides...... of internationalisation of higher education by harmonising diverse institutional structures. At the same time states are also in competition to attract and retain international students as future knowledge workers. Denmark is one of such countries where internationalisation of higher education stands high on the national...... an insight into some of the key challenges surrounding the internationalisation of higher education in the quest for highly skilled labour in the context of knowledge economy....

  4. 2nd International Conference on Multiphase Flow - ICMF '95

    CERN Document Server

    Fukano, T; Bataille, Jean

    1995-01-01

    There is increasing world-wide interest in obtaining an understanding of various multiphase flow phenomena and problems in terms of a common language of multiphase flow. This volume contains state-of-the-art papers which have been contributed from all over the world by experts working on all aspects of multiphase flows. The volume also highlights international technology-sharing in the fields of energy, environment and public health, in order to create a brighter and sustainable future for man and for all life in the next century. It is intended that this volume will serve as a major source of

  5. International medical migration: a critical conceptual review of the global movements of doctors and nurses.

    Science.gov (United States)

    Bradby, Hannah

    2014-11-01

    This paper critically appraises the discourse around international medical migration at the turn of the 21st century. A critical narrative review of a range of English-language sources, including grey literature, books and research reports, traces the development and spread of specific causative models. The attribution of causative relations between the movement of skilled medical workers, the provision of health care and population health outcomes illustrates how the global reach of biomedicine has to be understood in the context of local conditions. The need to understand migration as an aspect of uneven global development, rather than a delimited issue of manpower services management, is illustrated with reference to debates about 'brain drain' of Africa's health-care professionals, task-shifting and the crisis in health-care human resources. The widespread presumed cause of shortages of skilled health-care staff in sub-Saharan Africa was overdetermined by a compelling narrative of rich countries stealing poor countries' trained health-care professionals. This narrative promotes medical professional interests and ignores historical patterns of underinvestment in health-care systems and structures. Sociological theories of medicalization suggest that the international marketization of medical recruitment is a key site where the uneven global development of capital is at work. A radical reconfiguration of medical staffing along the lines of 'task-shifting' in rich and poor countries' health-care systems alike offers one means of thinking about global equity in access to quality care.

  6. Cohort profile: internal migration in sub-Saharan Africa-The Migration and Health in Malawi (MHM) study.

    Science.gov (United States)

    Anglewicz, Philip; VanLandingham, Mark; Manda-Taylor, Lucinda; Kohler, Hans-Peter

    2017-05-17

    The Migration and Health in Malawi (MHM) study focuses on a key challenge in migration research: although it has long been established that migration and health are closely linked, identifying the effect of migration on various health outcomes is complicated by methodological challenges. The MHM study uses a longitudinal panel premigration and postmigration study design (with a non-migrant comparison group) to measure and/or control for important characteristics that affect both migration and health outcomes. Data are available for two waves. The MHM interviewed 398 of 715 migrants in 2007 (55.7%) and 722 of 1013 in 2013 (71.3%); as well as 604 of 751 (80.4%) for a non-migrant reference group in 2013. The total interviewed sample size for the MHM in both waves is 1809. These data include extensive information on lifetime migration, socioeconomic and demographic characteristics, sexual behaviours, marriage, household/family structure, social networks and social capital, HIV/AIDS biomarkers and other dimensions of health. Our result for the relationship between migration and health differs by health measure and analytic approach. Migrants in Malawi have a significantly higher HIV prevalence than non-migrants, which is primarily due to the selection of HIV-positive individuals into migration. We find evidence for health selection; physically healthier men and women are more likely to move, partly because migration selects younger individuals. However, we do not find differences in physical or mental health between migrants and non-migrants after moving. We are preparing a third round of data collection for these (and any new) migrants, which will take place in 2018. This cohort will be used to examine the effect of migration on various health measures and behaviours, including general mental and physical health, smoking and alcohol use, access to and use of health services and use of antiretroviral therapy. © Article author(s) (or their employer(s) unless otherwise

  7. Illegal migration flows through the Strait of Gibraltar / Los flujos migratorios ilegales en el Estrecho de Gibraltar

    Directory of Open Access Journals (Sweden)

    Jamal Benamar

    2007-10-01

    Full Text Available The migrations constitute an important factor in the international interchanges because they generate wealth for both populations of origin and of reception. In order that his perverse effects disappear it is necessary to seek to reduce like between all the existing abysses between the economies of the rich countries and those of Africa. The perverse effect of these movements, the illegal or clandestine immigration, is not a new phenomenon. This way of emigrating was tolerated by many countries of destiny, from the 50s up to the economic crisis and the crisis of the oil of the 70s. The permissiveness owed a lack to itself in the juridical regulation of the migratory flows (absence of laws and of a frontier strict control that was justifying itself for the need of growth of the European economies in a context of post-war period. This article tries to value the phenomenon of the illegal migrations today for the Strait of Gibraltar.

  8. Numerical Investigation of the Internal Flow in a Banki Turbine

    Directory of Open Access Journals (Sweden)

    Jesús De Andrade

    2011-01-01

    Full Text Available The paper refers to the numerical analysis of the internal flow in a hydraulic cross-flow turbine type Banki. A 3D-CFD steady state flow simulation has been performed using ANSYS CFX codes. The simulation includes nozzle, runner, shaft, and casing. The turbine has a specific speed of 63 (metric units, an outside runner diameter of 294 mm. Simulations were carried out using a water-air free surface model and k-ε turbulence model. The objectives of this study were to analyze the velocity and pressure fields of the cross-flow within the runner and to characterize its performance for different runner speeds. Absolute flow velocity angles are obtained at runner entrance for simulations with and without the runner. Flow recirculation in the runner interblade passages and shocks of the internal cross-flow cause considerable hydraulic losses by which the efficiency of the turbine decreases significantly. The CFD simulations results were compared with experimental data and were consistent with global performance parameters.

  9. Internal Flow of Contra-Rotating Small Hydroturbine at Off- Design Flow Rates

    Science.gov (United States)

    SHIGEMITSU, Toru; TAKESHIMA, Yasutoshi; OGAWA, Yuya; FUKUTOMI, Junichiro

    2016-11-01

    Small hydropower generation is one of important alternative energy, and enormous potential lie in the small hydropower. However, efficiency of small hydroturbines is lower than that of large one. Then, there are demands for small hydroturbines to keep high performance in wide flow rate range. Therefore, we adopted contra-rotating rotors, which can be expected to achieve high performance. In this research, performance of the contra-rotating small hydroturbine with 60mm casing diameter was investigated by an experiment and numerical analysis. Efficiency of the contra-rotating small hydroturbine was high in pico-hydroturbine and high efficiency could be kept in wide flow rate range, however the performance of a rear rotor decreased significantly in partial flow rates. Then, internal flow condition, which was difficult to measure experimentally, was investigated by the numerical flow analysis. Then, a relation between the performance and internal flow condition was considered by the numerical analysis result.

  10. International Conference on Instability and Control of Massively Separated Flows

    CERN Document Server

    Soria, Julio

    2015-01-01

    This book contains the outcome of the international meeting on instability, control and noise generated by massive flow separation that was organized at the Monash Center, in Prato, Italy, September 4-6, 2013. The meeting served as the final review of the EU-FP7 Instability and Control of Massively Separated Flows Marie Curie travel grant and was supported by the European Office of Aerospace Research and Development. Fifty leading specialists from twelve countries reviewed the progress made since the 50s of the last century and discussed modern analysis techniques, advanced experimental flow diagnostics, and recent developments in active flow control techniques from the incompressible to the hypersonic regime. Applications involving massive flow separation and associated instability and noise generation mechanisms of interest to the aeronautical, naval and automotive industries have been addressed from a theoretical, numerical or experimental point of view, making this book a unique source containing the stat...

  11. International migration and national development in sub-Saharan Africa : viewpoints and policy initiatives in the countries of origin

    NARCIS (Netherlands)

    Adepoju, Aderanti; Naerssen, Ton van; Zoomers, Annelies

    2008-01-01

    This book aims at achieving a better understanding of the implications of international migration for national development from the perspective of the sending countries, with an emphasis on sub-Saharan Africa. More specifically, the volume explores (1) current perceptions of the links between intern

  12. International migration and national development in sub-Saharan Africa : viewpoints and policy initiatives in the countries of origin

    NARCIS (Netherlands)

    Adepoju, Aderanti; Naerssen, Ton van; Zoomers, Annelies

    2008-01-01

    This book aims at achieving a better understanding of the implications of international migration for national development from the perspective of the sending countries, with an emphasis on sub-Saharan Africa. More specifically, the volume explores (1) current perceptions of the links between intern

  13. Emotional Problems and Victimisation among Youth with National and International Migration Experience Living in Austria and Turkey

    Science.gov (United States)

    Strohmeier, Dagmar; Dogan, Aysun

    2012-01-01

    Young people with international migration experiences constitute an increasing proportion of the population in many European countries. In Austria, a substantial proportion of these international migrants come from Turkey. In Turkey, many adolescents are national migrants, having moved from the eastern part to the western part of the country. This…

  14. Electrohydrodynamic migration of a spherical drop in a general quadratic flow

    CERN Document Server

    Mandal, Shubhadeep; Chakraborty, Suman

    2015-01-01

    We investigate the motion of a spherical drop in a general quadratic flow acted upon by an arbitrarily oriented externally applied uniform electric field. The drop and media are considered to be leaky dielectrics. The flow field affects the distribution of charges on the drop surface, which leads to alteration in the electric field, thereby affecting the velocity field through the Maxwell stress on the fluid-fluid interface. The two-way coupled electrohydrodynamics is central towards dictating the motion of the drop in the flow field. We analytically address the electric potential distribution and Stokesian flow field in and around the drop in a general quadratic flow for small electric Reynolds number (which is the ratio of the charge relaxation time scale to the convective time scale). As a special case, we consider a drop in an unbounded cylindrical Poiseuille flow and show that, an otherwise absent, cross-stream drop migration may be obtained in the presence of a uniform electric field. Depending on the d...

  15. OECD migration, welfare and skill selectivity

    DEFF Research Database (Denmark)

    Pedersen, Peder; Pytlikova, Mariola; Smith, Nina

    into 27 OECD countries over the period of 12 years, 1989-2000. Using a fixed effects panel data model, we analyze the determinants of the migration flows during the latest decade. We study whether there are significant selectivity effects in international migration flows, i.e. whether the countries...

  16. FFF 92: Third international symposium on field-flow fractionation

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This is a collection of abstracts from the Third International Symposium on Field-Flow Fractionation. Topics were covered in the areas of environmental analysis, pharmaceutical applications, polymer analysis, particle characterization, and theory and optimization. Individual articles are abstracted and indexed separately.

  17. International fund flows: surges, sudden stops, and cyclicality

    NARCIS (Netherlands)

    Li, Suxiao

    2017-01-01

    International fund flows are cross-border investments in domestic equity and bond markets by global investment funds. They have increased dramatically since the 1990s and played an increasingly important role in the transmission of shocks. In this thesis, we examine the drivers of large changes in

  18. International fund flows: surges, sudden stops, and cyclicality

    NARCIS (Netherlands)

    Li, Suxiao

    2017-01-01

    International fund flows are cross-border investments in domestic equity and bond markets by global investment funds. They have increased dramatically since the 1990s and played an increasingly important role in the transmission of shocks. In this thesis, we examine the drivers of large changes in f

  19. International fund flows: surges, sudden stops, and cyclicality

    NARCIS (Netherlands)

    Li, Suxiao

    2017-01-01

    International fund flows are cross-border investments in domestic equity and bond markets by global investment funds. They have increased dramatically since the 1990s and played an increasingly important role in the transmission of shocks. In this thesis, we examine the drivers of large changes in f

  20. Coordination of Flow and Traction in Migration of Amoeboid Physarum polycephalum: Model and Measurement

    Science.gov (United States)

    Lewis, Owen; Guy, Robert; Zhang, Shun; Del Alamo, Juan Carlos

    2014-11-01

    In this research, we develop a computational model of crawling Physarum based on the Immersed Boundary Method. Our model incorporates the effects of cell cytoplasm, the internal cytoskeleton and adhesions to the substrate. Cytoplasmic flows and traction stresses predicted by the model are compared to experimentally measured values obtained using simultaneous Traction Force Microscopy (TFM) and Particle Image Velocimetry (PIV). Of particular interest are stresses generated by flow and how transmission of stresses to the substrate is coordinated. We identify methods of adhesion-flow coordination which are consistent with experiments. Certain consisten coordinations are seen to be ``optimal'' with regards to crawling speed, and robust to perturbations in the extracellular environment.

  1. Effect of dextran 500 on radial migration of erythrocytes in postcapillary venules at low flow rates.

    Science.gov (United States)

    Kim, Sangho; Ong, Peng Kai; Johnson, Paul C

    2009-06-01

    Recently, we reported that collision efficiency (fraction of total collisions that result in the formation of aggregates) between red blood cells was an important factor in the formation of aggregates in postcapillary venules. In the present study, we focus on how high molecular weight dextran influences the overall radial migration trend of red blood cells in the postcapillary venule along a longitudinal distance of 50 microm from the bifurcation which would in turn affect collision behavior of these cells. A radial migration index, which defines the extent of radial migration of individual cells relative to the vessel center, was found to have a larger magnitude after infusion of dextran (1.9 +/- 2.73) compared to that before dextran infusion (1.48 +/- 3.89). This implied that dextran-induced aggregation might provide an external force to actively move cells towards the centerline of the vessel, which could contribute to the greater number of red blood cells participating in collision (16% increase) and aggregate formation. Further analysis of the collision behavior of individual red blood cells revealed that collision frequencies of individual cells decreased from a wide range (1 to 14) to a narrow range (1 to 5) after dextran treatment, indicating the alteration of collision behavior of red blood cells by the presence of aggregates along the flow stream.

  2. The migration and growth of nuclei in an ideal vortex flow

    Science.gov (United States)

    Zhang, Lingxin; Chen, Linya; Shao, Xueming

    2016-12-01

    Tip vortex cavitation occurs on ship propellers which can cause significant noise compared to the wet flow. In order to predict the inception of tip vortex cavitation, numerous researches have been investigated about the detailed flow field around the tip. According to informed studies, the inception of tip vortex cavitation is affected by many factors. To understand the effect of water quality on cavitation inception, the motion of nuclei in an ideal vortex flow, i.e., the Rankine vortex flow, was investigated. The one-way coupling point-particle tracking model was employed to simulate the trajectory of nuclei. Meanwhile, Rayleigh-Plesset equation was introduced to describe the growth of nuclei. The results show that the nucleus size has a significant effect on nucleus' trajectory. The capture time of a nucleus is approximately inversely proportional to its radius. The growth of nucleus accelerates its migration in the vortex flow and shortens its capture time, especially for the case of explosive growth.

  3. Globalization and formal sector migration in Brazil

    OpenAIRE

    Aguayo-Tellez, Ernesto; Muendler, Marc-Andreas; Poole, Jennifer Pamela

    2008-01-01

    We use novel linked employer–employee data to study the relationship between globalization and formal sector interstate migration for Brazil. We estimate the worker’s multichoice migration problem and document that previously unobserved employer covariates are significant predictors associated with migration flows. Our results provide support for the idea that globalization acts on internal migration through the growth of employment opportunities at locations with a high concentration of fore...

  4. Modeling Particle Concentration In Slurry Flows Using Shear-Induced Migration: Theory vs. Experiments

    Science.gov (United States)

    Lin, Kanhui; Latterman, Paul; Koch, Trystan; Hu, Vincent; Ho, Joyce; Mata, Matthew; Murisic, Nebojsa; Bertozzi, Andrea

    2009-11-01

    Different flow regimes observed in our experimental study of particle-laden thin film flows are characterized by differing particle concentration profiles. We develop a theoretical model for particle concentration in order to capture our experimental observations. Our model is based on equilibrium assumption and it incorporates all relevant physical mechanisms, including shear-induced particle migration and settling due to gravity. It leads to a coupled system of ordinary differential equations for particle volume fraction and shear, which are solved numerically for various parameter sets. We find excellent agreement between our numerical results and experimental data. Our model is not only successful in reproducing the experimentally observed regimes, but also in capturing the connection between these regimes and the experimental parameters.

  5. Migration, foraging, and residency patterns for Northern Gulf loggerheads: implications of local threats and international movements.

    Directory of Open Access Journals (Sweden)

    Kristen M Hart

    Full Text Available Northern Gulf of Mexico (NGoM loggerheads (Caretta caretta make up one of the smallest subpopulations of this threatened species and have declining nest numbers. We used satellite telemetry and a switching state-space model to identify distinct foraging areas used by 59 NGoM loggerheads tagged during 2010-2013. We tagged turtles after nesting at three sites, 1 in Alabama (Gulf Shores; n = 37 and 2 in Florida (St. Joseph Peninsula; n = 20 and Eglin Air Force Base; n = 2. Peak migration time was 22 July to 9 August during which >40% of turtles were in migration mode; the mean post-nesting migration period was 23.0 d (±13.8 d SD. After displacement from nesting beaches, 44 turtles traveled to foraging sites where they remained resident throughout tracking durations. Selected foraging locations were variable distances from tagging sites, and in 5 geographic regions; no turtles selected foraging sites outside the Gulf of Mexico (GoM. Foraging sites delineated using 50% kernel density estimation were located a mean distance of 47.6 km from land and in water with mean depth of -32.5 m; other foraging sites, delineated using minimum convex polygons, were located a mean distance of 43.0 km from land and in water with a mean depth of -24.9 m. Foraging sites overlapped with known trawling activities, oil and gas extraction activities, and the footprint of surface oiling during the 2010 Deepwater Horizon oil spill (n = 10. Our results highlight the year-round use of habitats in the GoM by loggerheads that nest in the NGoM. Our findings indicate that protection of females in this subpopulation requires both international collaborations and management of threats that spatially overlap with distinct foraging habitats.

  6. From surnames to linguistic and genetic diversity: five centuries of internal migrations in Spain.

    Science.gov (United States)

    Rodríguez-Díaz, Roberto; Blanco-Villegas, María José; Manni, Franz

    2017-09-01

    In a previous study concerning 33,753 single Spanish surnames (considered as tokens) occurring 51,419,788 times we have shown that the present-day geography of contemporary surname variability in Spain still corresponds to the political geography of the country at the end of the Middle Ages. Here we reprocess the same database, by clustering surnames with Self-Organizing Maps (SOMs) according to their geographic distribution, to identify the monophyletic surnames showing a geo-historical origin in one of the 47 provinces of continental Spain. They are 25,714, and they occur 12,348,109 times, meaning that about 75% of the Spanish population bears a surname that had a polyphyletic origin. From monophyletic surnames we compute migration matrices accounting for the internal migrations that took place since five centuries ago, when Spanish surnames started to be patrilineally inherited. The mono/ polyphyletic classification we obtain fits ancient census data and is compatible with published molecular diversity of the Y-chromosomes associated to selected Spanish surnames. Monophyletic surnames indicate that i) the provinces exhibiting a higher percentage of autochthonous surnames are also ii) those from which emigration corresponds to a local isolation-by-distance model of diffusion and iii) those that attracted a lower number of immigrants. These are also the provinces where languages other than Castilian are spoken. We suggest that demographic stability explains linguistic resilience, as people prefer to move to areas in which the linguistic variety is more similar to their own. So far the reciprocal influence of migration and language has been investigated at local scales, here we outline how to investigate it at national scales and for time-depths of centuries.

  7. Migration, foraging, and residency patterns for Northern Gulf loggerheads: implications of local threats and international movements.

    Science.gov (United States)

    Hart, Kristen M; Lamont, Margaret M; Sartain, Autumn R; Fujisaki, Ikuko

    2014-01-01

    Northern Gulf of Mexico (NGoM) loggerheads (Caretta caretta) make up one of the smallest subpopulations of this threatened species and have declining nest numbers. We used satellite telemetry and a switching state-space model to identify distinct foraging areas used by 59 NGoM loggerheads tagged during 2010-2013. We tagged turtles after nesting at three sites, 1 in Alabama (Gulf Shores; n = 37) and 2 in Florida (St. Joseph Peninsula; n = 20 and Eglin Air Force Base; n = 2). Peak migration time was 22 July to 9 August during which >40% of turtles were in migration mode; the mean post-nesting migration period was 23.0 d (±13.8 d SD). After displacement from nesting beaches, 44 turtles traveled to foraging sites where they remained resident throughout tracking durations. Selected foraging locations were variable distances from tagging sites, and in 5 geographic regions; no turtles selected foraging sites outside the Gulf of Mexico (GoM). Foraging sites delineated using 50% kernel density estimation were located a mean distance of 47.6 km from land and in water with mean depth of -32.5 m; other foraging sites, delineated using minimum convex polygons, were located a mean distance of 43.0 km from land and in water with a mean depth of -24.9 m. Foraging sites overlapped with known trawling activities, oil and gas extraction activities, and the footprint of surface oiling during the 2010 Deepwater Horizon oil spill (n = 10). Our results highlight the year-round use of habitats in the GoM by loggerheads that nest in the NGoM. Our findings indicate that protection of females in this subpopulation requires both international collaborations and management of threats that spatially overlap with distinct foraging habitats.

  8. Geography of European Migration

    Directory of Open Access Journals (Sweden)

    Zhitin Dmitry V.

    2016-08-01

    Full Text Available In recent decades, the role of international migration has increased dramatically in most European countries. The growth in migration has made some authors proclaim the beginning of a second Migration Period that could transform the social and cultural identity of Europe. The article presents an analysis of international migration geography in Europe in the last twenty-five years. The authors identify the main trends in migration, provide migration profiles of European countries, and propose a classification based on the recent changes in the migrant stock. Changes in the migrant stock (total emigration and immigration reflect the level of involvement in international and global processes. They can serve as an indicator of a country’s attractiveness for both foreigners and the country’s citizens. The study shows that European countries are increasingly split into ‘immigrant’ and ‘emigrant’ states. The authors describe spatial patterns of migration. The volume and localisation of migration flows in Europe are affected not only by cultural and historical circumstance, such as a colonial past or a common language. The scale of immigrant influx often does not depend on a donor country’s demographic potential or the level of its socio-economic development. The links between the place of origin and destination are often more complex than it might initially seem. The authors stress the importance of a differentiated immigration policy taking into account ethnic and cultural features of host societies.

  9. Observations of shear-induced particle migration for oscillatory flow of a suspension within a tube

    Science.gov (United States)

    Butler, Jason E.; Majors, Paul D.; Bonnecaze, Roger T.

    1999-10-01

    Suspensions of noncolloidal, neutrally buoyant, spherical particles were subjected to oscillating displacements at low Reynolds number along the axis of a circular tube. Using nuclear magnetic resonance imaging (NMRI), the phase distribution of a suspension with a particle volume fraction 0.4 was assessed for a variety of conditions. The variables studied included ratio of particle to tube diameter, amplitude of oscillation, and number of oscillations. Consistent with macroscopic theories of shear-induced particle migration, the particles preferentially moved away from the walls and to the center of the pipe for amplitudes of oscillation much greater than the particle diameter when the ratios of particle radius to tube radius were 6.4×10-3 and 1.48×10-2. However, for a ratio of particle radius to tube radius of 6.4×10-3, the images showed that the suspension was not uniform along the tube length for an amplitude of oscillation equivalent to one pipe diameter. For a larger ratio of particle radius to tube radius of 1.48×10-2, the suspension remained uniform along the pipe for similar conditions. For the smaller ratio of particle to tube radius of 6.4×10-3 and an amplitude of oscillation of five particle radii, the particles migrated to the wall of the pipe as predicted by the Stokesian dynamics simulations of Morris ["Anomalous particle migration in oscillatory pressure-driven suspension flow," presented at the 1997 Annual Meeting of the AICHE (unpublished)]. These phenomena, which have not previously been observed experimentally, are not described by any existing theories of shear-induced particle migration.

  10. Return migration.

    Science.gov (United States)

    Gmelch, G

    1980-01-01

    The author reviews the findings of the growing literature on return migration. Topics covered include typologies of return migrants, reasons for return, adaptation and readjustment of returnees, and the impact of return migration on the migrants' home societies. The focus of the study is on international return migration, migration to Northern Europe and northeastern North America, and return migration to the southern and eastern fringes of Europe and the Caribbean

  11. Novel elution strategy for monitoring DNA counter-migration in the presence of electroosmotic flow.

    Science.gov (United States)

    Zabzdyr, Jennifer L; Lillard, Sheri J

    2004-06-25

    The migration behavior of native (i.e., unlabelled) DNA in the presence of electroosmotic flow (EOF) was investigated in bare fused-silica capillaries. Employing a novel elution strategy, the influence of EOF on the net mobility of DNA was assessed by collecting the DNA that migrated anodically (i.e., against EOF) and out of the capillary inlet. Various conditions of pH and buffer-zone continuity were employed to characterize this phenomenon. Tris acid (TA, pH 5.14) and Tris base (TB, pH 9.36) were used as buffers in continuous systems, in which the capillary and the inlet reservoir contain the same buffer, and discontinuous systems, in which the capillary contains either TA or TB, and the inlet reservoir contains water. DNA that was ejected into the inlet vial was subsequently analyzed by capillary electrophoresis-laser-induced fluorescence. Both phiX174/HaeIII DNA and the beta-actin product of single-cell reverse transcriptase-polymerase chain reaction were used as DNA samples in this study. The mechanism of elution was found to depend on bulk flow, in the case of continuous solutions. However, with the discontinuous system, a localized decrease in EOF generated in the capillary tip appeared to impact elution. These findings serve to introduce an alternative approach for characterizing the mobility of highly charged species.

  12. FOREWORD: International Symposium of Cavitation and Multiphase Flow (ISCM 2014)

    Science.gov (United States)

    Wu, Yulin

    2015-01-01

    The International Symposium on Cavitation and Multiphase Flow (ISCM 2014) was held in Beijing, China during 18th-21st October, 2014, which was jointly organized by Tsinghua University, Beijing, China and Jiangsu University, Zhenjiang, China. The co-organizer was the State Key Laboratory of Hydroscience and Engineering, Beijing, China. Cavitation and multiphase flow is one of paramount topics of fluid mechanics with many engineering applications covering a broad range of topics, e.g. hydraulic machinery, biomedical engineering, chemical and process industry. In order to improve the performances of engineering facilities (e.g. hydraulic turbines) and to accelerate the development of techniques for medical treatment of serious diseases (e.g. tumors), it is essential to improve our understanding of cavitation and Multiphase Flow. For example, the present development towards the advanced hydrodynamic systems (e.g. space engine, propeller, hydraulic machinery system) often requires that the systems run under cavitating conditions and the risk of cavitation erosion needs to be controlled. The purpose of the ISCM 2014 was to discuss the state-of-the-art cavitation and multiphase flow research and their up-to-date applications, and to foster discussion and exchange of knowledge, and to provide an opportunity for the researchers, engineers and graduate students to report their latest outputs in these fields. Furthermore, the participants were also encouraged to present their work in progress with short lead time and discuss the encountered problems. ISCM 2014 covers all aspects of cavitation and Multiphase Flow, e.g. both fundamental and applied research with a focus on physical insights, numerical modelling and applications in engineering. Some specific topics are: Cavitating and Multiphase Flow in hydroturbines, pumps, propellers etc. Numerical simulation techniques Cavitation and multiphase flow erosion and anti-erosion techniques Measurement techniques for cavitation and

  13. Interregional Migration in Spain: A Semiparametric Analysis

    OpenAIRE

    Maza Fernández, Adolfo Jesús; Villaverde Castro, José

    2004-01-01

    This paper analyses the determinants of internal migration in Spain between 1995 and 2002. After a brief descriptive study, we present an analytical model of internal migration flows. Subsequently, we estimate this model by applying semiparametric techniques. The general conclusion that we come to is that net migration rates are influenced mainly by income and climatic condition differentials between the regions of origin and destination; in addition, unemployment and housin...

  14. Analysis of receptor tyrosine kinase internalization using flow cytometry.

    Science.gov (United States)

    Li, Ning; Hill, Kristen S; Elferink, Lisa A

    2008-01-01

    The internalization of activated receptor tyrosine kinases (RTKs) by endocytosis and their subsequent down regulation in lysosomes plays a critical role in regulating the duration and intensity of downstream signaling events. Uncoupling of the RTK cMet from ligand-induced degradation was recently shown to correlate with sustained receptor signaling and increased cell tumorigenicity, suggesting that the corruption of these endocytic mechanisms could contribute to increased cMet signaling in metastatic cancers. To understand how cMet signaling for normal cell growth is controlled by endocytosis and how these mechanisms are dysregulated in metastatic cancers, we developed flow cytometry-based assays to examine cMet internalization.

  15. Inertial migration in dilute and semidilute suspensions of rigid particles in laminar square duct flow

    Science.gov (United States)

    Kazerooni, H. Tabaei; Fornari, W.; Hussong, J.; Brandt, L.

    2017-08-01

    We study the inertial migration of finite-size neutrally buoyant spherical particles in dilute and semidilute suspensions in laminar square duct flow. We perform several direct numerical simulations using an immersed boundary method to investigate the effects of the bulk Reynolds number Reb, particle Reynolds number Rep, and duct to particle size ratio h /a at different solid volume fractions ϕ , from very dilute conditions to 20 % . We show that the bulk Reynolds number Reb is the key parameter in inertial migration of particles in dilute suspensions. At low solid volume fraction (ϕ =0.4 % ), low bulk Reynolds number (Reb=144 ), and h /a =9 particles accumulate at the center of the duct walls. As Reb is increased, the focusing position moves progressively toward the corners of the duct. At higher volume fractions, ϕ =5 % , 10 % , and 20 % , and in wider ducts (h /a =18 ) with Reb=550 , particles are found to migrate away from the duct core toward the walls. In particular, for ϕ =5 % and 10 % , particles accumulate preferentially at the corners. At the highest volume fraction considered, ϕ =20 % , particles sample all the volume of the duct, with a lower concentration at the duct core. For all cases, we find that particles reside longer times at the corners than at the wall centers. In a duct with lower duct to particle size ratio h /a =9 (i.e., with larger particles), ϕ =5 % , and high bulk Reynolds number Reb=550 , we find a particle concentration pattern similar to that in the ducts with h /a =9 regardless of the solid volume fraction ϕ . Instead, for lower Bulk Reynolds number Reb=144 , h /a =9 , and ϕ =5 % , a different particle distribution is observed in comparison to a dilute suspension ϕ =0.4 % . Hence, the volume fraction plays a key role in defining the final distribution of particles in semidilute suspensions at low bulk Reynolds number. The presence of particles induces secondary cross-stream motions in the duct cross section, for all ϕ . The

  16. Integrated modeling of European migration

    OpenAIRE

    Raymer, James; Wiśniowski, Arkadiusz; Forster, Jonathan J.; Peter W. F. Smith; Bijak, Jakub

    2013-01-01

    International migration data in Europe are collected by individual countries with separate collection systems and designs. As a result, reported data are inconsistent in availability, definition and quality. In this paper, we propose a Bayesian model to overcome the limitations of the various data sources. The focus is on estimating recent international migration flows amongst 31 countries in the European Union and European Free Trade Association from 2002 to 2008, using data collated by Euro...

  17. Adaptive computational methods for SSME internal flow analysis

    Science.gov (United States)

    Oden, J. T.

    1986-01-01

    Adaptive finite element methods for the analysis of classes of problems in compressible and incompressible flow of interest in SSME (space shuttle main engine) analysis and design are described. The general objective of the adaptive methods is to improve and to quantify the quality of numerical solutions to the governing partial differential equations of fluid dynamics in two-dimensional cases. There are several different families of adaptive schemes that can be used to improve the quality of solutions in complex flow simulations. Among these are: (1) r-methods (node-redistribution or moving mesh methods) in which a fixed number of nodal points is allowed to migrate to points in the mesh where high error is detected; (2) h-methods, in which the mesh size h is automatically refined to reduce local error; and (3) p-methods, in which the local degree p of the finite element approximation is increased to reduce local error. Two of the three basic techniques have been studied in this project: an r-method for steady Euler equations in two dimensions and a p-method for transient, laminar, viscous incompressible flow. Numerical results are presented. A brief introduction to residual methods of a-posterior error estimation is also given and some pertinent conclusions of the study are listed.

  18. Portal vein blood flow is related to characteristics of the migrating motor complex of the gastrointestinal tract

    DEFF Research Database (Denmark)

    Qvist, Niels; Rafaelsen, Søren Rafael; Troensegaard, P.

    1994-01-01

    Objective: To measure variation in portal blood flow during the interdigestive state in relation to the migrating motor complex (MMC) in healthy volunteers. Design: Portal blood flow was measured by a duplex and colour Doppler technique with 5-min intervals during an entire MMC cycle. Total....... Conclusion: Blood flow in the portal vein varies with the characteristics of the MMC, a relationship which must be considered in future studies in health and disease....

  19. Internal Acoustics of a Pintle Valve with Supercritical Helium Flow

    Science.gov (United States)

    Fishbach, Sean R.; Davis, R. Benjamin

    2010-01-01

    Large amplitude flow unsteadiness is a common phenomenon within the high flow rate ducts and valves associated with propulsion systems. Boundary layer noise, shear layers and vortex shedding are a few of the many sources of flow oscillations. The presence of lightly damped acoustic modes can organize and amplify these sources of flow perturbation, causing undesirable loading of internal parts. The present study investigates the self-induced acoustic environment within a pintle valve subject to high Reynolds Number flow of helium gas. Experiments were conducted to measure the internal pressure oscillations of the Ares I Launch Abort System (LAS) Attitude Control Motor (ACM) valve. The AGM consists of a solid propellant gas generator with eight pintle valves attached to the aft end. The pintle valve is designed to deliver variable upstream conditions to an attache( converging diverging nozzle. In order to investigate the full range of operating conditions 28 separate tests were conducted with varying pintle position and upstream pressure. Helium gas was utilized in order to closely mimic the speed of sound of the gas generator exhaust, minimizing required scaling during data analysis. The recordec pressure measurements were interrogated to multiple ends. The development of root mean square (RMS) value! versus Reynolds Number and Pintle position are important to creating bounding unsteady load curves for valve internal parts. Spectral analysis was also performed, helping to identify power spectral densities (PSD) of acoustic natural frequencies and boundary layer noise. An interesting and unexpected result was the identification of an acoustic mode within the valve which does not respond until the valve was over 60% open. Further, the response amplitude around this mode can be as large or larger than those associated with lower frequency modes.

  20. EU Migration Policy

    OpenAIRE

    Kleinschmidt, Harald

    2004-01-01

    I shall confine myself in this paper to international migration as migration across international borders.I do so despite the fact that,still today,international migration accounts only for a small share of migration at large.Likewise,I shall deal widh voluntary migration and shall thus exclude,deportation ...

  1. Internal flow measurements of drop impacting a solid surface

    Science.gov (United States)

    Kumar, S. Santosh; Karn, Ashish; Arndt, Roger E. A.; Hong, Jiarong

    2017-03-01

    Understanding the fundamental physical process involved in drop impacts is important for a variety of engineering and scientific applications. Despite exhaustive research efforts on the dynamics of drop morphology upon impact, very few studies investigate the fluid dynamics induced within a drop upon impact. This study employs planar particle image velocimetry (PIV) with fluorescent particles to quantify the internal flow field of a drop impact on a solid surface. The image distortion caused by the curved liquid-air interface at the drop boundary is corrected using a ray-tracing algorithm. PIV analysis using the corrected images has yielded interesting insights into the flow initiated within a drop upon impact. Depending on the pre-impact conditions, characterized by impact number, different vortex modes are observed in the recoil phase of the drop impact. Further, the strength of these vortices and the kinetic energy of the internal flow field have been quantified. Our studies show a consistent negative power law correlation between vortex strength, internal kinetic energy and the impact number.

  2. Capillary channel flow experiments aboard the International Space Station

    Science.gov (United States)

    Conrath, M.; Canfield, P. J.; Bronowicki, P. M.; Dreyer, M. E.; Weislogel, M. M.; Grah, A.

    2013-12-01

    In the near-weightless environment of orbiting spacecraft capillary forces dominate interfacial flow phenomena over unearthly large length scales. In current experiments aboard the International Space Station, partially open channels are being investigated to determine critical flow rate-limiting conditions above which the free surface collapses ingesting bubbles. Without the natural passive phase separating qualities of buoyancy, such ingested bubbles can in turn wreak havoc on the fluid transport systems of spacecraft. The flow channels under investigation represent geometric families of conduits with applications to liquid propellant acquisition, thermal fluids circulation, and water processing for life support. Present and near future experiments focus on transient phenomena and conduit asymmetries allowing capillary forces to replace the role of gravity to perform passive phase separations. Terrestrial applications are noted where enhanced transport via direct liquid-gas contact is desired.

  3. Capillary channel flow experiments aboard the International Space Station.

    Science.gov (United States)

    Conrath, M; Canfield, P J; Bronowicki, P M; Dreyer, M E; Weislogel, M M; Grah, A

    2013-12-01

    In the near-weightless environment of orbiting spacecraft capillary forces dominate interfacial flow phenomena over unearthly large length scales. In current experiments aboard the International Space Station, partially open channels are being investigated to determine critical flow rate-limiting conditions above which the free surface collapses ingesting bubbles. Without the natural passive phase separating qualities of buoyancy, such ingested bubbles can in turn wreak havoc on the fluid transport systems of spacecraft. The flow channels under investigation represent geometric families of conduits with applications to liquid propellant acquisition, thermal fluids circulation, and water processing for life support. Present and near future experiments focus on transient phenomena and conduit asymmetries allowing capillary forces to replace the role of gravity to perform passive phase separations. Terrestrial applications are noted where enhanced transport via direct liquid-gas contact is desired.

  4. Tail dependence and information flow: Evidence from international equity markets

    Science.gov (United States)

    Al Rahahleh, Naseem; Bhatti, M. Ishaq; Adeinat, Iman

    2017-05-01

    Bhatti and Nguyen (2012) used the copula approach to measure the tail dependence between a number of international markets. They observed that some country pairs exhibit only left-tail dependence whereas others show only right-tail. However, the flow of information from uni-dimensional (one-tail) to bi-dimensional (two-tails) between various markets was not accounted for. In this study, we address the flow of information of this nature by using the dynamic conditional correlation (DCC-GARCH) model. More specifically, we use various versions of the DCC models to explain the nexus between the information flow of international equity and to explain the stochastic forward vs. backward dynamics of financial markets based on data for a 15-year period comprising 3,782 observations. We observed that the information flow between the US and Hong Kong markets and between the US and Australian markets are bi-directional. We also observed that the DCC model captures a wider co-movement structure and inter-connectedness compared to the symmetric Joe-Clayton copula.

  5. Analysis of diabatic flow modification in the internal boundary layer

    DEFF Research Database (Denmark)

    Floors, Rogier; Gryning, Sven-Erik; Pena Diaz, Alfredo

    2011-01-01

    is controlled by a combination of both downstream and upstream stability and surface roughness conditions. A model based on a diffusion analogy is able to predict the internal boundary layer height well. Modeling the neutral and long-term wind profile with a 3 layer linear interpolation scheme gives good......Measurements at two meteorological masts in Denmark, Horns Rev in the sea and Høvsøre near the coastline on land, are used to analyze the behaviour of the flow after a smooth-to-rough change in surface conditions. The study shows that the wind profile within the internal boundary layer...... results at Høvsøre. Based on a comparison with a numerical model and the measurements, the constants in the interpolation scheme are slightly adjusted, which yields an improvement for the description of the wind profile in the internal boundary layer....

  6. Medical migration: A qualitative exploration of the atypical path of Japanese international medical graduates.

    Science.gov (United States)

    Heist, Brian S; Torok, Haruka Matsubara

    2017-08-25

    International Medical Graduates (IMGs) are commonly understood to move from low to high resource countries with motivations including improved financial situations and cultures of emigration. A presumable exception to the above themes would be the Japanese IMG population. The aim of this study was to develop an understanding of the Japanese IMG experience. Using a grounded theory approach, we interviewed 19 Japanese IMGs working in the US and 16 Japanese IMGs working in Japan who had completed US clinical training. Questions addressed decision-making to pursue US clinical training, goals for the training, and career decision-making upon completing the training. Data collection and constant comparative analysis were conducted iteratively to identify emerging themes. The emerging model of the Japanese IMG experience is focused around pivotal experiences that often include dissatisfaction with the quality of Japanese clinical training and personal exposures to US clinical education. Further decision-making in the pursuit of US residency is influenced by educator training quality, and clinical training and career opportunities. The desire to improve Japanese clinical training commonly influences career decision-making after US training. The Japanese IMG experience contrasts numerous perceptions of international physician migration and, in turn, enhances understanding of this paradigm.

  7. Changes in dietary habits following temporal migration. The case of international students in Belgium.

    Science.gov (United States)

    Perez-Cueto, Federico; Verbeke, Wim; Lachat, Carl; Remaut-De Winter, Anne Marie

    2009-02-01

    This paper reports findings from a cross-sectional survey carried out in April-May 2006 among international students enrolled at Ghent University in Belgium. The aim of the study was to assess their knowledge and attitudes related to nutrition, perceived changes in dietary habits, perceived barriers to healthy eating and the determinants of dietary changes since their arrival in Belgium. In total, 235 students from 60 countries participated. Following the reported dietary changes, which were factor-analyzed into "less energy-dense" foods, "more fruits and vegetables" and "less processed" foods, three clusters could be identified. Cluster 1 composed of students who increased their fruits, vegetables and fiber intake. Cluster 2, the largest, reported dietary changes overall and in particular towards less processed foods. Cluster 3 composed of students who changed in the main towards less energy-dense foods. Gender differences were observed in healthy dietary changes, particularly in males. Healthier choices were hindered by a perceived unavailability of healthy food products. Gender and availability of healthy foods should be taken into consideration when informing temporal migration populations, such as international students in this study, about the healthy food options available during their stay in a different cultural, food and dietary environment.

  8. Migration of health workers.

    Science.gov (United States)

    Buchan, James

    2008-01-01

    The discussion and debate stimulated by these papers focused across a range of issues but there were four main areas of questioning: "measuring" and monitoring migration (issues related to comparability, completeness and accuracy of data sets on human resources); the impact of migration of health workers on health systems; the motivations of individual health workers to migrate (the "push" and "pull" factors) and the effect of policies designed either to reduce migration (e.g "self ufficiency") or to stimulate it (e.g active international recruitment). It was recognised that there was a critical need to examine migratory flows within the broader context of all health care labour market dynamics within a country, that increasing migration of health workers was an inevitable consequence of globalisation, and that there was a critical need to improve monitoring so as to better inform policy formulation and policy testing in this area.

  9. The 'global interconnectedness' of dentist migration: a qualitative study of the life-stories of international dental graduates in Australia.

    Science.gov (United States)

    Balasubramanian, Madhan; Brennan, David S; Spencer, A John; Short, Stephanie D

    2015-05-01

    The migration of dentists is a major challenge contributing to the oral health system crisis in many countries. This paper explores the origins of the dentist migration problem through a study on international dental graduates, who had migrated to Australia. Life-stories of 49 international dental graduates from 22 countries were analysed in order to discern significant themes and patterns. We focused on their home country experience, including stories on early life and career choice; dental student life; professional life; social and political life; travels; and coming to Australia. Our participants exhibited a commitment to excellence in earlier stages of life and had cultivated a desire to learn more and be involved with the latest technology. Dentists from low- and middle-income countries were also disappointed by the lack of opportunity and were unhappy with the local ethos. Some pointed towards political unrest. Interestingly, participants also carried prior travel learnings and unforgettable memories contributing to their migration. Family members and peers had also influenced participants. These considerations were brought together in four themes explaining the desire to migrate: 'Being good at something', 'Feelings of being let down', 'A novel experience' and 'Influenced by someone'. Even if one of these four themes dominated the narrative, we found that more than one theme, however, coexisted for most participants. We refer to this worldview as 'Global interconnectedness', and identify the development of migration desire as a historical process, stimulated by a priori knowledge (and interactions) of people, place and things. This qualitative study has enriched our understanding on the complexity of the dental migration experience. It supports efforts to achieve greater technical co-operation in issues such as dental education, workforce surveillance and oral health service planning within the context of ongoing global efforts on health professional

  10. Movements of the ‘we’ : International and transnational migration and the capabilities approach

    NARCIS (Netherlands)

    D.R. Gasper (Des); T-D. Truong (Thanh-Dam)

    2010-01-01

    textabstractWe consider cross-border migration through the lens of the capabilities approach, with special reference to transnational migration and to implications for the approach itself. Cross-border migration has profound and diverse effects, not least because it accelerates change in the nature

  11. International cross-border migration in the South-East Baltic: factors, structure, consequences

    Directory of Open Access Journals (Sweden)

    Yemelyanova Larisa

    2010-12-01

    Full Text Available This article presents the results of an integrated research encompassing both the study of migration processes in the South-East Baltic (volume, structure, directions and the analysis of factors affecting migration mobility of the population as well as the assessment of migration influence on the socioeconomic development of three border territories.

  12. The formation and migration of sand ripples in closed conduits: experiments with turbulent water flows

    CERN Document Server

    Florez, Jorge Eduar Cardona

    2016-01-01

    The transport of solid particles by a fluid flow is frequently found in nature and industry. Some examples are the transport of sand in rivers and hydrocarbon pipelines. When the shear stresses exerted by a fluid flow on a granular bed remain moderate, some grains are set in motion without fluidizing the bed; the moving grains form a layer, known as bed load, that moves while maintaining contact with the fixed part of the bed. Under bed load conditions, the granular bed may become unstable, generating ripples and dunes. Sand ripples are commonly observed in closed conduits and pipes such as in petroleum pipelines, sewer systems, and dredging lines. Although of importance for many scientific domains and industrial applications, the formation of ripples in closed conduits is not well understood, and the problem is still open. This paper presents an experimental study on the formation and migration of sand ripples under a turbulent closed-conduit flow and bed-load conditions. In our experiments, fully-developed ...

  13. Nanoparticle Migration in a Fully Developed Turbulent Pipe Flow Considering the Particle Coagulation

    Institute of Scientific and Technical Information of China (English)

    林建忠; 刘淞; 陈达良

    2012-01-01

    Numerical simulations of nanoparticle migration in a fully developed turbulent pipe flow are performed.The evolution of particle number concentration,total particle mass,polydispersity,particle diameter and geometric standard deviation is obtained by using a moment method to approximate the particle general dynamic equation.The effects of Schmidt number and Damkhler number on the evolution of the particle parameters are analyzed.The results show that nanoparticles move to the pipe center.The particle number concentration and total particle mass are distributed non-uniformly along the radial direction.In an initially monodisperse particle field,the particle clusters with various sizes will be produced because of coagulation.As time progresses,the particle cluster diameter grows from an initial value at different rates depending on the radial position.The largest particle clusters are found in the pipe center.The particle cluster number concentration and total particle mass decrease with the increase of Schmidt number in the region near the pipe center,and the particles with lower Schmidt number are of many dif-ferent sizes,i.e.more polydispersity.The particle cluster diameter and geometric standard deviation increase with the increase of Damkhler number at the same radial position.The migration properties for nano-sized particles are different from that for micro-sized particles.

  14. Analysing the Demography and Migration Related Challenges within the Internal Periphery of South-Heves

    Directory of Open Access Journals (Sweden)

    Tunde Bogardi

    2015-04-01

    Full Text Available The purpose of my study is to perform an analysis with the application of regional statistical data, in order to understand the changes within the number of the population at South-Heves in the past period, and to the reveal its special characteristics compared to regional, national trends. The examined area is a classic internal periphery, a region “hit severely by social, economic and environmental crisis” (according to the draft proposal of Heves county’s regional development concept (2014-2020. Considering such regions, besides the examination of the intention to migrate, it is also important to see who will remain in the region. Experiences show that in case of regions with a more disadvantageous situation than average, generally classes of lower social statuses will become dominant, while as it is described by Győri-Nagy (2003, “the escape of competent classes of the population” can be observed. It results in a contra-selected local society which is unable to retain the young and ambitious. The future of the affected regions, settlements is largely determined by the perspectives perceived by young people who live there, and who shall start their families and careers there in the near future. I have conducted an empirical research amongst high-school students living and studying at South-Heves, focusing on issues such as whether the high-school age-group of this classic periphery is considering migration; if so, then what are the reasons, destinations, and as an important question from the aspect of the national strategy as well, how could these young people who are longing to go elsewhere manage their lives here, and how could we make them stay in their homeland (in a narrow sense. By investigating the intention to migrate, we also receive indirect answers for questions such as how could significant regional differences be reduced, and how could we close the gap in case of the most disadvantageous regions.

  15. Comparison of lattice-Boltzmann and brownian-dynamics simulations of polymer migration in confined flows.

    Science.gov (United States)

    Kekre, Rahul; Butler, Jason E; Ladd, Anthony J C

    2010-07-01

    This paper compares results from lattice-Boltzmann and brownian-dynamics simulations of polymer migration in confined flows bounded by planar walls. We have considered both a uniform shear rate and a constant pressure gradient. Lattice-Boltzmann simulations of the center-of-mass distribution agree quantitatively with brownian-dynamics results, contradicting previously published results. The mean end-to-end distance of the extended polymer is more sensitive to grid resolution Δx and time-step Δt. Nevertheless, for sufficiently small Δx and Δt, convergent results for the polymer stretch are obtained which agree with brownian dynamics within statistical uncertainties. The brownian-dynamics simulations incorporate a mobility matrix for a confined polymer that is both symmetric and positive definite for all physically accessible configurations.

  16. Changing Academic Mobility Patterns and International Migration: What Will Academic Mobility Mean in the 21St Century?

    Science.gov (United States)

    Hoffman, David M.

    2009-01-01

    Several scholars have underlined connections between academic mobility and international migration. This qualitative study explores a spectrum of academic mobility articulated by Teichler that empirically contributes to consideration of these connections. This analysis of e-mail excerpts from 20 migrant academics, living in seven countries,…

  17. Selection or network effects? Migration flows into 27 OECD countries, 1990-2000

    DEFF Research Database (Denmark)

    Pedersen, Peder J.; Pytlikova, Mariola; Smith, Nina

    Recent migration patterns show growing migration pressure and changing composition of immigrants in many Western countries. During the latest decade, an increasing proportion of the OECD immigrants have been from poor countries, where the educational level of the population is low. The migration ...... evidence that selection effects have had a major influence on the observed migration patterns until now. This may partly be explained by restrictive migration policies in many OECD countries which may have dampened the potential selection effects....

  18. Selection or Network Effects? Migration Flows into 27 OECD Countries, 1990-2000

    DEFF Research Database (Denmark)

    Pedersen, P.J.; Pytlikova, Mariola; Smith, Nina

    Recent migration patterns show growing migration pressure and changing composition of immigrants in many Western countries. During the latest decade, an increasing proportion of the OECD immigrants have been from poor countries, where the educational level of the population is low. The migration ...... evidence that selection effects have had a major influence on the observed migration patterns until now. This may partly be explained by restrictive migration policies in many OECD countries which may have dampened the potential selection effects....

  19. Modeling the meander morphodynamics with internal boundary conditions given by a localized variation in the flow field

    Science.gov (United States)

    Lanzoni, S.; Bogoni, M.; Nittrouer, J. A.; Cantelli, A.

    2016-12-01

    Modeling of long-term evolution of meander planforms is usually applied to river reaches characterized by a uniform flow perturbed by the effects of the curvature and width distributions. However, in nature meandering rivers may be characterized by localized variations due to external conditions, e.g. changes in floodplain slope (geologic variation), confluence of a tributary into the main river (hydrologic variation), or backwater effects (hydrodynamic variation). As a consequence, the hypothesis of a sufficiently long reach having constant forcing characteristic could limit the reliability of the numerical simulations. We developed a mathematical extension of a well-known fully coupled two-dimensional morphodynamic model (i.e., the ZS model) able to manage an internally localized boundary condition which affects the characteristic of the main flow. The resulting modular model computes the flow field in the two meandering sub-reaches determined by the presence of a section entailing prescribed changes in external conditions, and simulates the long-term lateral migration above the floodplain surface due to erosion and deposition processes at the banks, and the possible occurrence of neck cutoffs. Calibration runs and simulations based on real test cases show that internal variations in the parameters controlling the flow field might strongly affect the morphodynamic behavior of the migrating planforms. Future research shall provide an extension of this approach in order to manage multiple internal boundary conditions within the investigated river reach. The aim is to relax the common hypothesis of a unique formative uniform flow, exploiting the less restrictive assumption of a sequence of uniform flows to describe the flow field that establishes in the river and controls its morphodynamic behaviour.

  20. Intensity and patterns redistributive effect of internal migration in Cuba and the Dominican Republic. According DAM and DAME. 2000 and 2010 census rounds

    Directory of Open Access Journals (Sweden)

    Arelis Rosalén Mora Pérez

    2016-07-01

    Full Text Available Aware of the differences and similarities in the socioeconomic and demographic contexts that characterize Cuba and the Dominican Republic, is made from the information collected in the Census of Population and Housing of the two countries in the rounds 2000 and 2010, a study on migration internal. A summary of the management of census questions regarding the recruitment of absolute internal migration of lifetime and recent migration fixed date five years ago. The research is conducted in order to identify how has been the evolution of the intensity, the redistributive effect and profile of internal migration in Cuba and the Dominican Republic as Administrative Divisions Major and Minor (DAM and DAME. Different migration indicators: net migration, proportion of non-migrants, net migration rate (TMN, overall intensity (rate of internal mobility, immigration effectiveness index (IEM, and aggregate net migration rate (TAMN are used to explain behavior. Migrant profile analysis are performed by age, sex and educational level and regularities are articulated in the redistributive and intensity of internal migration effect generating attractive specialization of these administrative units. Generally, it can be seen in Cuba, the migration intensity between the two census moments remained constant level DAM, while among DAME a decrease of this intensity is appreciated. In the case of the Dominican Republica, reduction stands.

  1. International Migration and Human Development in Destination Countries: A Cross-National Analysis of Less-Developed Countries, 1970-2005

    Science.gov (United States)

    Sanderson, Matthew

    2010-01-01

    Contemporary levels of international migration in less-developed countries are raising new and important questions regarding the consequences of immigration for human welfare and well-being. However, there is little systematic cross-national evidence of how international migration affects human development levels in migrant-receiving countries in…

  2. International Migration and Human Development in Destination Countries: A Cross-National Analysis of Less-Developed Countries, 1970-2005

    Science.gov (United States)

    Sanderson, Matthew

    2010-01-01

    Contemporary levels of international migration in less-developed countries are raising new and important questions regarding the consequences of immigration for human welfare and well-being. However, there is little systematic cross-national evidence of how international migration affects human development levels in migrant-receiving countries in…

  3. Modeling performance of a two-dimensional capsule in a microchannel flow: long-term lateral migration.

    Science.gov (United States)

    Li, Hua; Ma, Gang

    2010-08-01

    The long-term lateral migration of a two-dimensional elastic capsule in a microchannel is studied numerically in this paper. The numerical method combines a finite volume technique for solving the fluid problem with a front tracking technique for capturing and tracking the capsule membrane. The capsule is modeled as a liquid medium enclosed by a thin membrane which has linear elastic properties. The capsule, whose initial shape is circle and which starts from a near-center position or a near-wall position, experiences tilting and membrane tank-treading, and migrates laterally when moving along the surrounding flow. The lateral migration demonstrates the existence of lift effect of surrounding flow on moving capsule. Before capsule approaches to the microchannel centerline closely, lower membrane dilation modulus and lower viscosity ratio tend to result in faster lateral migration. The initial position also influences the performance behavior of capsule, despite the lateral migration of capsule is a quasisteady process. Small difference in capsule behavior when capsule is not near to the microchannel centerline might lead to significant difference in capsule behavior when capsule approaches closely to the centerline. When capsules are near to microchannel wall, the effect of the wall on capsule behavior might dominate, leading to relatively faster lateral migration. When capsules are not far from microchannel centerline, the effect of the nonlinearity of Poiseuille flow might dominate, resulting in relatively slower lateral movement. When capsules are located closely to the centerline, they behave differently, where the reason still remains poorly understood and it will be one of our future studies. The comparison between the capsule behavior from the present simulation and that by the migration law proposed by Coupier [Phys. Fluids 20, 111702 (2008)] shows that the behavioral agreement for near-wall capsule is better than that for near-center capsule, and the best

  4. International Capital Flows and Yields of Public Debt Bonds

    OpenAIRE

    Márcia Saraiva Leon

    2014-01-01

    The paper analyzes nominal yields of five-year fixed-rate Brazilian Domestic Federal Public Debt (DFPD) bonds in response to fluctuations in international net capital flows to Brazil for the period January 2007 to July 2012. The results show that estimation in differences with error correction obtains a long-run relationship between the yield, the foreign participation in the DFPD and the target Selic rate that reproduces previous results. When the ratio of net foreign long-term fixed-income ...

  5. International student mobility and highly skilled migration: a comparative study of Canada, the United States, and the United Kingdom.

    Science.gov (United States)

    She, Qianru; Wotherspoon, Terry

    2013-12-01

    Against the backdrop of demographic change and economic reconfiguration, recruiting international students, especially those at tertiary level, has drawn growing attention from advanced economies as part of a broad strategy to manage highly skilled migration. This comparative study focuses on three English speaking countries receiving international students: Canada, the United States, and the United Kingdom. International student policies, in particular entry and immigration regulations, and the trends in student mobility since the late 1990s are examined drawing on secondary data. By exploring the issue from the political economy perspectives, this study identifies distinct national strategies for managing student mobility, determines key factors shaping the environment of student migration in each nation, and addresses the deficiency of human capital theory in the analysis of global competition for high skills.

  6. Migration of a droplet in a cylindrical tube in the creeping flow regime

    Science.gov (United States)

    Nath, Binita; Biswas, Gautam; Dalal, Amaresh; Sahu, Kirti Chandra

    2017-03-01

    The migration of a neutrally buoyant droplet in a tube containing another immiscible liquid is investigated numerically in the creeping flow regime. A fully developed velocity profile is imposed at the inlet of the tube. The interface between the two immiscible fluids is captured using a coupled level-set and volume-of-fluid approach. The deformation and breakup dynamics of the droplet are investigated in terms of three dimensionless parameters, namely, the ratio between the radius of the undeformed droplet and the radius of the capillary tube, the viscosity ratio between the dispersed and the continuous phases, and the capillary number that measures the relative importance of the viscous force over the surface tension force. It has been observed that the droplet, while traversing through the tube, either approaches a steady bulletlike shape or develops a prominent reentrant cavity at its rear. Depending on the initial droplet size, there exists a critical capillary number for every flow configuration beyond which the drop fails to maintain a steady shape and breaks into fragments. The deformation and breakup phenomena depend primarily on the droplet size, the viscosity ratio, and the capillary number. Special attention has been given to the case where the drop diameter is comparable with the tube diameter. A thorough computational study has been conducted to find the critical capillary number for a range of droplets of varied sizes suspended in systems having different viscosity ratios.

  7. Migration experiences, employment status and psychological distress among Somali immigrants: a mixed-method international study

    Directory of Open Access Journals (Sweden)

    Warfa Nasir

    2012-09-01

    Full Text Available Abstract Background The discourse about mental health problems among migrants and refugees tends to focus on adverse pre-migration experiences; there is less investigation of the environmental conditions in which refugee migrants live, and the contrasts between these situations in different countries. This cross-national study of two samples of Somali refugees living in London (UK and Minneapolis, Minnesota, (USA helps to fill a gap in the literature, and is unusual in being able to compare information collected in the same way in two cities in different countries. Methods There were two parts to the study, focus groups to gather in-depth qualitative data and a survey of health status and quantifiable demographic and material factors. Three of the focus groups involved nineteen Somali professionals and five groups included twenty-eight lay Somalis who were living in London and Minneapolis. The quantitative survey was done with 189 Somali respondents, also living in London and Minneapolis. We used the MINI International Neuropsychiatric Interview (MINI to assess ICD-10 and DSM-IV mental disorders. Results The overall qualitative and quantitative results suggested that challenges to masculinity, thwarted aspirations, devalued refugee identity, unemployment, legal uncertainties and longer duration of stay in the host country account for poor psychological well-being and psychiatric disorders among this group. Conclusion The use of a mixed-methods approach in this international study was essential since the quantitative and qualitative data provide different layers and depth of meaning and complement each other to provide a fuller picture of complex and multi-faceted life situations of refugees and asylum seekers. The comparison between the UK and US suggests that greater flexibility of access to labour markets for this refugee group might help to promote opportunities for better integration and mental well-being.

  8. International migration, sex ratios, and the socioeconomic outcomes of nonmigrant Mexican women.

    Science.gov (United States)

    Raphael, Steven

    2013-06-01

    This article assesses whether international migration from Mexico affects the marital, fertility, schooling, and employment outcomes of the Mexican women who remain behind by exploiting variation over time as well as across Mexican states in the demographic imbalance between men and women. I construct a gauge of the relative supply of men for women of different age groups based on state-level male and female population counts and the empirically observed propensity of men of specific ages to marry women of specific ages. Using Mexican census data from 1960 through 2000, I estimate a series of models in which the dependent variable is the intercensus change in an average outcome for Mexican women measured by state and for specific age groups, and the key explanatory variable is the change in the relative supply of men to women in that state/age group. I find that the declining relative supply of males positively and significantly affects the proportion of women who have never been married as well as the proportion of women who have never had a child. In addition, states experiencing the largest declines in the relative supply of men also experience relatively large increases in female educational attainment and female employment rates. However, I find little evidence that women who do marry match to men who are younger or less educated than themselves.

  9. Accidental subretinal brilliant blue G migration during internal limiting membrane peeling surgery.

    Science.gov (United States)

    Almeida, Felipe P P; De Lucca, Ana Claudia; Scott, Ingrid Ursula; Jorge, Rodrigo; Messias, Andre

    2015-01-01

    This case report describes a man who developed retinal changes in his right eye associated with brilliant blue G migration into the subretinal space during 2 years of follow-up. The patient's best-corrected visual acuity in the right eye was 20/70 before surgery, and it improved to 20/25 at 1 year after surgery. Fluorescein angiography showed staining during the late phase in the central macula at all follow-up visits after surgery. Multifocal electroretinography demonstrated normal amplitude and implicit times before surgery but decreased amplitudes and increased implicit times in at least 5 contiguous hexagons after surgery on all 3 examinations performed during the 2-year follow-up period. These functional changes were not topographically correlated with the area of fluorescein staining or with the internal limiting membrane peeled area, but were matched to the area where brilliant blue G accidentally entered the subretinal space. Microperimetry demonstrated reduced retinal threshold sensitivity, particularly in areas with decreased multifocal electroretinography amplitude. Despite the visual acuity improvement observed in this case, multifocal electroretinography and microperimetry indicate that subretinal brilliant blue G might cause focal macular damage with a decrease of macular function suggestive of a toxic effect.

  10. Risk of psychosis and internal migration: Results from the Bologna First Episode Psychosis study.

    Science.gov (United States)

    Tarricone, Ilaria; Boydell, Jane; Kokona, Arnisa; Triolo, Federico; Gamberini, Lisa; Sutti, Enrico; Marchetta, Michela; Menchetti, Marco; Di Forti, Marta; Murray, Robin M; Morgan, Craig; Berardi, Domenico

    2016-05-01

    Incidence of psychotic disorders is higher in many migrant groups; however little is known about internal migrants (IM). This study aims to describe the IR in natives (NA), IM and external migrants (EM). All patients aged 18-64years, with First Episode Psychosis (FEP), who made contact with the Bologna West psychiatric services, between 2002 and 2010, were included. 187 cases were included. Age and sex adjusted IR of psychosis per 100,000per year were: 12.6 for NA, 25.3 for IM and 21.4 for EM. The IRR was 1.93 (1.19-3.13, P=0.007) for IM and 1.79 (1.06-3.02, P=0.03) for EM compared to NA. Rates of psychosis were significantly elevated in IM as well as in EM. This result adds evidence as to the role of migration itself (versus ethnicity) on the risk of psychosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Analysis of the migration characteristics of tracers in a heterogeneous flow field through a natural fracture of a domestic granite

    Energy Technology Data Exchange (ETDEWEB)

    Kum, Y. S.; Park, J. K.; Han, P. S. [KAERI, Taejon (Korea, Republic of)

    2001-05-01

    Tracers migration experiment was performed in a natural fracture of a domestic granite. The scale of rock fracture was 100x60x40(cm). In order to observe the migration characteristics, two kinds of nonsorbing tracers were used; as high molecular organic dyes, Eosine, and NaLS, and as anions, Bromide and Chloride. Tracers was injected in a borehole as a band funtion and collected at the opposite borehole. A variable aperture channel model with particle tracking method was used to characterize the aperture width of the fracture and to simulate solute transport. The heterogeneous flow field was modeled by a variable aperture channel model after characterizing aperture distribution by hydraulic tests through boreholes. The particle tracking method applied effectively in simulating tracers transport through a heterogeneous flow field in the rock fracture. Simulated results show that tracers do not migrate through the shortest straight line between inlet and outlet, but migrate through the paths having lowest flow resistance. that is channeling flow.

  12. Migration and environmental change in international governance: the case of the European Union

    OpenAIRE

    2012-01-01

    With this paper we analyse and assess the role of the European Union (EU) in the governance of migration linked to environmental change. We trace the emergence of migration linked to environmental change as an issue on the EU agenda and examine both issue definition and the institutional location of EU responses. The EU is identified as a particularly significant potential actor in the broader debate about environmental change and migration, as it is the world’s most developed form of regiona...

  13. CONSIDERATIONS ON THE TRENDS OF INTERNATIONAL TOURIST FLOWS

    Directory of Open Access Journals (Sweden)

    Agatha POPESCU

    2014-12-01

    Full Text Available The paper purpose was the purpose to analyze the flow of international tourists in the period 1980-2012 uisng the empirical data provided by UNWTO. In 2012, tourist arrivals reached 1,035 and in 2030 it is expected to exceed 1,800 million. The market share of main geographical regions in 2012 was the following one: Europe 51.61 %, Asia and the Pacific 22.57 %, the Americas 15.75 %, Africa 5.06 % and the Middle East 5.01 %. The top 10 countries receiving tourists and their market share at world level was the following one: France 8.21 %, the USA 6.63 %, China 5.71 %, Spain 5.71 %, Italy 4.59 %, Turkey 3.53 %, Germany 3 %, United Kingdom 2.90 %, Russia 2.54 %, Malayezia 2.47 %. All these 10 countries were visited by 457.9 million tourists in 2012, representing 45.75 % of the world tourist arrivals. Europe is the main source of international tourists, supplying over 50 % of the world tourists, followed by Asia and the Pacific with 23 %, the Americas with 17 %, the Middle East with 3 % and Africa with 3 %. Europe generates the most important tourism flows

  14. A Solution to Two Paradoxes of International Capital Flows

    Institute of Scientific and Technical Information of China (English)

    JIANDONG; JU; SHANG-JIN; WEI

    2014-01-01

    International capital flows from rich to poor countries can be regarded as either too small(the Lucas paradox in a one-sector model)or too large(when compared with the logic of factor price equalization in a two-sector model).To resolve the paradoxes,we introduce a non-neoclassical model which features financial contracts and firm heterogeneity.In our model,free trade in goods does not imply equal returns to capital across countries.In addition,rich patterns of gross capital flows emerge as a function of financial and property rights institutions.A poor country with an inefficient financial system may simultaneously experience an outflow of financial capital but an inflow of FDI,resulting in a small net flow.In comparison,a country with a low capital-to-labor ratio but a high risk of expropriation may experience an outflow of financial capital without a compensating inflow of FDI.

  15. Nutrient flows in international trade: Ecology and policy issues

    Energy Technology Data Exchange (ETDEWEB)

    Grote, Ulrike [Center for Development Research (ZEF), University of Bonn, Walter-Flex Str. 3, 53113 Bonn (Germany)]. E-mail: u.grote@uni-bonn.de; Craswell, Eric [Center for Development Research (ZEF), University of Bonn, Walter-Flex Str. 3, 53113 Bonn (Germany); Vlek, Paul [Center for Development Research (ZEF), University of Bonn, Walter-Flex Str. 3, 53113 Bonn (Germany)

    2005-10-01

    Impacts of increasing population pressure on food demand and land resources has sparked interest in nutrient balances and flows at a range of scales. West Asia/North Africa, China, and sub-Saharan Africa are net importers of NPK in agricultural commodities. These imported nutrients do not, however, redress the widely recognized declines in fertility in sub-Saharan African soils, because the nutrients imported are commonly concentrated in the cities, creating waste disposal problems rather than alleviating deficiencies in rural soils. Countries with a net loss of NPK in agricultural commodities are the major food exporting countries-the United States, Australia, and some Latin American countries. In the case of the United States, exports of NPK will increase from 3.1 Tg in 1997 to 4.8 Tg in 2020. The results suggest that between 1997 and 2020, total international net flows of NPK in traded agricultural commodities will double to 8.8 million tonnes. Against this background, the paper analyses the impact of different policy measures on nutrient flows and balances. This includes not only the effects of agricultural trade liberalization and the reduction of subsidies, but also the more direct environmental policies like nutrient accounting schemes, eco-labeling, and nutrient trading. It finally stresses the need for environmental costs to be factored into the debate on nutrient management and advocates more inter-disciplinary research on these important problems.

  16. Fleeing through the Globalised Education System: The Role of Violence and Conflict in International Student Migration

    Science.gov (United States)

    Kirkegaard, Ane Marie Ørbø; Nat-George, Sisse Mari-Louise Wulff

    2016-01-01

    This article connects directly to the globalisation of both education and conflict, and attends to the intersection between these phenomena, by focusing on conflict-induced student migration, an area, which has until recently been neglected in studies of higher education and migration, and peace and conflict research. The focus is on the very…

  17. Inactive supply wells as conduits for flow and contaminant migration: conditions of occurrence and suggestions for management

    Science.gov (United States)

    Gailey, Robert M.

    2017-05-01

    Water supply wells can act as conduits for vertical flow and contaminant migration between water-bearing strata under common hydrogeologic and well construction conditions. While recognized by some for decades, there is little published data on the magnitude of flows and extent of resulting water quality impacts. Consequently, the issue may not be acknowledged widely enough and the need for better management persists. This is especially true for unconsolidated alluvial groundwater basins that are hydrologically stressed by agricultural activities. Theoretical and practical considerations indicate that significant water volumes can migrate vertically through wells. The flow is often downward, with shallow groundwater, usually poorer in quality, migrating through conduit wells to degrade deeper water quality. Field data from locations in California, USA, are presented in combination with modeling results to illustrate both the prevalence of conditions conducive to intraborehole flow and the resulting impacts to water quality. Suggestions for management of planned wells include better enforcement of current regulations and more detailed consideration of hydrogeologic conditions during design and installation. A potentially greater management challenge is presented by the large number of existing wells. Monitoring for evidence of conduit flow and solute transport in areas of high well density is recommended to identify wells that pose greater risks to water quality. Conduit wells that are discovered may be addressed through approaches that include structural modification and changes in operations.

  18. The effects of integration and transnational ties on international return migration intentions

    Directory of Open Access Journals (Sweden)

    Hein de Haas

    2011-12-01

    Full Text Available While return migration is receiving increasing attention, there is still insufficient insight into the factors which determine migrants' intentions and decisions to return. It is often assumed that integration in receiving countries and the concomitant weakening of transnational ties decreases the likelihood of returning. However, according to alternative theoretical interpretations, return migration can also be the outflow of successful integration in receiving countries. Drawing on a data set of four African immigrant groups in Spain and Italy, this articlereviews these conflicting hypotheses by assessing the effects of integration and transnational ties on return migration intentions. The results of the analysis suggest that socio-cultural integration has a negative effect on return migration intentions, while economic integration and transnational ties have more ambiguous and sometimes positive effects. The results provide mixed support for the different hypotheses but question theoretical perspectives that unequivocally conceptualizereturn migration and transnationalism as causes and/or consequences of "integration failure".

  19. The Impact of Internal Migration on under-Five Mortality in 27 Sub-Saharan African Countries.

    Science.gov (United States)

    Issaka, Abukari I; Agho, Kingsley E; Renzaho, Andre M N

    2016-01-01

    The literature on the impact of internal migration on under-five mortality in sub-Saharan Africa has been limited. This study examined the impact of internal migration on under-five mortality rate in 27 sub-Saharan African countries. The analysis used cross-sectional data from the most recent Demographic and Health Surveys of 27 sub-Saharan African countries. Information on the number of live births and the number of under-five deaths in the five years preceding the surveys in these countries was examined. Using variables from which migration data were generated, four migration statuses were computed, and the impact of each migration status on under-five mortality was analysed by using multivariate Cox proportional hazards regression models. Of the 96333 live births, 7036 deaths were reported. In the unadjusted model, we found that, compared to urban non-migrant mothers, hazard of under-five mortality was 20% [HR: 1.20; 95% confidence interval (CI): (1.06–1.35)], 40% [HR: 1.40; 95% CI: (1.29–1.53)], and 43% [HR: 1.43; 95% CI: (1.30–1.58)] higher among urban-rural migrant, rural non-migrant, and rural-urban migrant mothers respectively. The likelihood of children dying did not change considerably when country and demographic variables were adjusted for. However, after controlling for health care service utilization factors, the results remained consistently significant for rurality. That is, mortality rates remained significantly higher among children of rural non-migrant [(HR: 1.20; 95% CI: (1.08–1.33), P-value (p) internal migrant mothers.

  20. From Migration Corridors to Clusters: The Value of Google+ Data for Migration Studies

    CERN Document Server

    Messias, Johnnatan; Weber, Ingmar; Zagheni, Emilio

    2016-01-01

    Recently, there have been considerable efforts to use online data to investigate international migration. These efforts show that Web data are valuable for estimating migration rates and are relatively easy to obtain. However, existing studies have only investigated flows of people along migration corridors, i.e. between pairs of countries. In our work, we use data about "places lived" from millions of Google+ users in order to study migration "clusters", i.e. groups of countries in which individuals have lived. For the first time, we consider information about more than two countries people have lived in. We argue that these data are very valuable because this type of information is not available in traditional demographic sources which record country-to-country migration flows independent of each other. We show that migration clusters of country triads cannot be identified using information about bilateral flows alone. To demonstrate the additional insights that can be gained by using data about migration c...

  1. THE CONTEMPORARY METHODOLOGICAL APPROACHES AND THEORIES EXPLAINING INTERNATIONAL TOURISM FLOWS

    Directory of Open Access Journals (Sweden)

    Zorina SISCAN

    2017-08-01

    Full Text Available Proceeding from the fact that international tourism is in permanent growth the last decades, and contributes signi­ficantly to the development of contemporary national economies, the authors of the article have focused on methodo­logical and theoretical frame that allows deeper understanding of the touristic flows from various aspects. In doing so, the first author has launched some methodological approaches that allow deepening a perspective research on touristic flows while the second author has concentrated upon grouping and analysis of existing theories used to explain touristic flows. As an outcome, the authors recommend a blend of those approaches and theories to be used for an adequate understanding and managing the existing and perspective touristic flows.ABORDDĂRI METODOLOGICE ȘI TEORII CONTEMPORANE CARE EXPLICĂ FLUXURILE DE TURISM INTERNAȚIONALPornind de la faptul că turismul internațional manifestă permanentă creștere în ultimele decenii, precum și contribuie semnificativ la dezvoltarea economiilor naționale contemporane, autorii articolului s-au axat pe cadrul metodologic și teoretic ce ar permite conceperea aprofundată a fluxurilor de turism internațional. Primul autor a lansat unele abordări metodologice care ar contribui la aprofundarea cercetărilor de perspectivă ale fluxurilor turistice, iar cel de-al doilea autor și-a concentrat atenția asupra grupării și analizei teoriilor existente în care se explică natura fluxurilor de turism. Ca rezultat, autorii recomandă utilizarea îmbinării organice a abordărilor și teoriilor considerate pentru perceperea și gestionarea adecvată a fluxurilor de turism existente și de perspectivă.

  2. Internal migration, mental health, and suicidal behaviors in young rural Chinese

    Science.gov (United States)

    Dai, Jing; Zhong, Bao-Liang; Xiang, Yu-Tao; Chiu, Helen F. K.; Chan, Sandra S. M.; Yu, Xin; Caine, Eric D.

    2015-01-01

    Purpose There is a dearth of data on the association of internal migration with mental health in young rural Chinese. This study aims to explore the associations between migrant status, mental health, and suicidal behaviors in young rural Chinese. Methods We recruited 1,646 rural subjects aged 16–34 years, of whom 756 were migrant workers and 890 non-migrants, from ten representative villages in rural Sichuan Province, the southwestern part of China. To assess subject's depressive symptoms and general psychological quality of life (psycho-QOL), the study protocol included the Centre for Epidemiological Studies Depression Scale, and psycho-QOL subscale of the World Health Organization's QOL Questionnaire-Brief Version, in addition to structured questions regarding one-year suicidal thoughts and behaviors (serious ideation, plan, and attempt), socio-demographic, social support, and physical health information. Results After adjustment for confounders, migrant workers had relative to non-migrant rural residents a decreased risk for depression (OR = 0.69, P = 0.026), but comparable risk for poor psycho-QOL (OR = 0.91, P = 0.557) and one-year suicidal behaviors (OR = 0.59–1.10, P = 0.19–0.90). Migrant status only accounted for 0.5, 2.8, 4.7, 9.8, and 12.6 % of the total explainable variance for suicide attempt, poor psycho-QOL, suicide plan, depression and serious suicide ideation, respectively. Conclusion Our findings suggested that among young rural Chinese there were no significant associations involving migrant status and poor psycho-QOL or one-year suicidal behaviors, while migrant status significantly correlated with a decreased risk of depression. The unique contribution of migrant status to mental health among young rural Chinese participants in this study was very small. PMID:25403568

  3. Internal migration, mental health, and suicidal behaviors in young rural Chinese.

    Science.gov (United States)

    Dai, Jing; Zhong, Bao-Liang; Xiang, Yu-Tao; Chiu, Helen F K; Chan, Sandra S M; Yu, Xin; Caine, Eric D

    2015-04-01

    There is a dearth of data on the association of internal migration with mental health in young rural Chinese. This study aims to explore the associations between migrant status, mental health, and suicidal behaviors in young rural Chinese. We recruited 1,646 rural subjects aged 16-34 years, of whom 756 were migrant workers and 890 non-migrants, from ten representative villages in rural Sichuan Province, the southwestern part of China. To assess subject's depressive symptoms and general psychological quality of life (psycho-QOL), the study protocol included the Centre for Epidemiological Studies Depression Scale, and psycho-QOL subscale of the World Health Organization's QOL Questionnaire-Brief Version, in addition to structured questions regarding one-year suicidal thoughts and behaviors (serious ideation, plan, and attempt), socio-demographic, social support, and physical health information. After adjustment for confounders, migrant workers had relative to non-migrant rural residents a decreased risk for depression (OR = 0.69, P = 0.026), but comparable risk for poor psycho-QOL (OR = 0.91, P = 0.557) and one-year suicidal behaviors (OR = 0.59-1.10, P = 0.19-0.90). Migrant status only accounted for 0.5, 2.8, 4.7, 9.8, and 12.6% of the total explainable variance for suicide attempt, poor psycho-QOL, suicide plan, depression and serious suicide ideation, respectively. Our findings suggested that among young rural Chinese there were no significant associations involving migrant status and poor psycho-QOL or one-year suicidal behaviors, while migrant status significantly correlated with a decreased risk of depression. The unique contribution of migrant status to mental health among young rural Chinese participants in this study was very small.

  4. A meta-analysis of the impacts of internal migration on child health outcomes in China.

    Science.gov (United States)

    Sun, Xiaoyue; Chen, Mengtong; Chan, Ko Ling

    2016-01-22

    According to China's 2010 population census, 38.81 million children migrated from rural to urban areas in Mainland China, a phenomenon that has attracted much scholarly attention. Due to the lack of quantitative synthesis of migrant children's developmental outcomes, we undertook a meta-analysis to compare their developmental outcomes with those of their urban counterparts. We searched Applied Social Sciences Index and Abstracts (ASSIA), Australian Education Index, British Education Index, ERIC, ProQuest Education Journals, PsycINFO, Social Services Abstracts, Family & Society Studies Worldwide, Medline, Women's Studies International databases and the Chinese CNKI database to identify relevant studies. Studies reporting physical and mental health outcomes of migrant children as well as potential protective and risk factors of child developmental outcomes were included. We assessed study quality using a quality assessment checklist. We selected 25 studies from a total of 1592. Our results reveal that migrant children in public schools present significantly greater mental health problems and lower well-being than their urban counterparts, while migrant children in migrant schools do not present significantly different outcomes. In addition, migrant children were found to be more likely to be exposed to physical health risks due to limited utilization of health services. The disadvantageous health outcomes of migrant children were found to be related to a series of individual and social factors, including academic performance, social relationships, and discrimination. Migrant children are disadvantaged by the sociocultural circumstances in urban areas. Government should target them and provide appropriate support in order to improve their developmental status, which will have a positive impact on the stability and development of society.

  5. International migration and educational assortative mating in Mexico and the United States.

    Science.gov (United States)

    Choi, Kate H; Mare, Robert D

    2012-05-01

    This paper examines the relationship between migration and marriage by describing how the distributions of marital statuses and assortative mating patterns vary by individual and community experiences of migration. In Mexico, migrants and those living in areas with high levels of out-migration are more likely to be in heterogamous unions. This is because migration increases the relative attractiveness of single return migrants while disproportionately reducing the number of marriageable men in local marriage markets. In the United States, the odds of homogamy are lower for migrants compared with nonmigrants; however, they do not vary depending on the volume of migration in communities. Migrants are more likely than nonmigrants to "marry up" educationally because the relatively small size of this group compels them to expand their pool of potential spouses to include nonmigrants, who tend to be better educated than they are. Among migrants, the odds of marrying outside of one's education group increase the most among the least educated. In Mexican communities with high rates of out-migration, the odds of marrying outside of one's education group are highest among those with the highest level of education. These findings suggest that migration disrupts preferences and opportunities for homogamy by changing social arrangements and normative climates.

  6. International importance of the eastern Chukchi Sea as a staging area for migrating king eiders

    Science.gov (United States)

    Oppel, S.; Dickson, D.L.; Powell, A.N.

    2009-01-01

    The evaluation of habitats used by arctic birds on migration is crucial for their conservation. We explored the importance of the eastern Chukchi Sea (ECS) as a staging area for king eiders (Somateria spectabilis) migrating between breeding areas in Siberia and western North America and wintering areas in the Bering Sea. We tracked 190 king eiders with satellite transmitters between 1997 and 2007. In late summer, 74% of satellite-tracked king eiders migrating south staged in the ECS for 13 ?? 13 (SD) days between late June and early November. During spring migration, king eiders staged in the ECS between mid-April and early June for 21 ?? 10 days. All instrumented birds migrating to breeding grounds in western North America (n = 62), and 6 of 11 males migrating to breeding grounds in Siberia, used this area for at least 1 week during spring migration. The importance of this staging area renders it possible that industrial development could adversely affect king eider populations in both Siberia and North America. ?? 2009 US Government.

  7. Determinants and consequences of internal and international migration: The case of rural populations in the south of Veracruz, Mexico

    Directory of Open Access Journals (Sweden)

    Luis Alberto del Rey Poveda

    2007-04-01

    Full Text Available This paper analyzes the current migration in rural population in the south of Veracruz state (Mexico. We identify three different spaces of migration, traditional markets, the northern border and the United States. Applying a multinomial logistic model and taking into account individual, family, and local characteristics of the migrants, we find different determinants in each space. These determinants are related to the objectives, needs and means of the migrants and their families. Otherwise, each space involves different consequences to the family in terms of the relationships between migrants and the rest of their relatives.

  8. Fracture and migration into the coronary sinus of a totally implantable catheter introduced via the right internal jugular vein.

    Science.gov (United States)

    Pignataro, Bruno Soriano; Nishinari, Kenji; Wolosker, Nelson; Bomfim, Guilherme Andre Zoteli

    2014-12-01

    There has been an increase in the use of totally implantable devices. Catheter fractures are rare but known complications. This case report presents a rare migration site of the catheter fragment into the coronary sinus. The totally implantable catheter was introduced into the right internal jugular vein to deliver chemotherapy. Although it was an unusual site, the catheter fragment was removed without complications using loop-snare technique. 2014 BMJ Publishing Group Ltd.

  9. An economic analysis of migration in Mexico.

    Science.gov (United States)

    Greenwood, M J; Ladman, J R

    1978-07-01

    This paper analyzes internal migration in Mexico over the 1960-70 period. A model of the determinants of migration is specified and estimated for aggregated interstate migration flows. Results show that distance serves as a significant deterrent to migration, that higher destination earning levels are attractive to migrants, and that regions with high unemployment rates experience lower rates of inmigration. An unanticipated finding is that regions with higher earning levels have greater rates of outmigration. The data are disaggregated to examine separate migration relationships for each state. The results are that distance is a lesser deterrent for those migrants with more accessible alternatives, that higher earning levels reduce the deterring effects of distance, and that regions with higher earning levels have lower associated elasticities of migration. It is concluded that economic factors have played a crucial role in internal migration and thus in the changing occupational and geographic structure of the Mexican labor force.

  10. A rotational compressible inverse design method for internal flow configurations

    Science.gov (United States)

    Dedoussis, V.; Chaviaropoulos, P.; Papailiou, K. D.

    The development of a rotational inviscid compressible inverse design method for two-dimensional internal flow configurations is described. Rotationality is due to an incoming entropy gradient, while total enthalpy is considered to be constant throughout the flowfield. The method is based on the potential function-streamfunction formulation. A novel procedure based on differential geometry arguments is employed to derive the governing equation for velocity by requiring the curvature of the two-dimensional Euclidean space to be zero. The velocity equation solved in conjunction with a transport equation for a thermal drift function provide the flowfield without any geometry feedback. An auxiliary orthogonal computational grid adapted to the solution is employed. Geometry is determined by integrating Frenet equations of the grid lines. Inverse calculation results are compared with results of direct reproduction calculations.

  11. Investigating droplet internal flow in concentrated emulsion when flowing in microchannel using micro-PIV

    Science.gov (United States)

    Leong, Chia Min; Gai, Ya; Tang, Sindy K. Y.

    2016-11-01

    Droplet microfluidics has enabled a wide variety of high throughput applications through the use of monodisperse droplets. Previous fluid studies of droplet microfluidics have focused on single drops or emulsions at low volume fractions. The study of concentrated emulsions at high volume fractions is important for increasing the throughput, but the fluid dynamics of such emulsions in confined channels is not well understood. Here we describe two-dimensional, mid-height measurements of the flow inside individual drops within a concentrated emulsion using micro-PIV. The emulsion has 85% volume fraction and flows as a monolayer in a straight microfluidic channel. The effects of confinement and viscosity ratio on the internal flow patterns inside the drops were studied. The results show rotational structures inside the drops always exist, and are independent of viscosity ratio for the conditions tested. The structures depend on droplet mobility which in turn, depends on the confinement of the emulsion and the location of the drops in the channel. To our best knowledge, no work has probed the flow field inside droplets of concentrated emulsions at high volume fractions in confined channels. Current work is in progress to measure the three-dimensional flow field in such system.

  12. EU Enlargement: Migration flows from Central and Eastern Europe into the Nordic countries - exploiting a natural experiment

    DEFF Research Database (Denmark)

    Pedersen, Peder J.; Pytlikova, Mariola

    , and Finland and Iceland from year 2006, the other Nordic countries chose a transition period in relation to the "new" EU members. The results based on a differences-in-differences estimator show that the estimated effect of the opening of the Swedish, Finnish and Icelandic labour markets on migration from......In this paper we look at migration flows from 10 Central and Eastern European Countries (CEEC) to 5 Nordic countries over the years 1985 - 2007. We exploit a natural experiment that arose from the fact that while Sweden opened its labour market from the day one of the 2004 EU enlargement...... the CEECs that entered the EU in 2004 is not significantly different from zero. However, the effect of the opening of the Swedish and Finnish labour markets in 2007 on migration from the 2007 EU entrants, Bulgaria and Romania, is significantly positive. Further, we are interested in the overall effect...

  13. Migration and population genetics of the grain aphid Macrosiphum miscanti (Takahashi) in relation to the geographic distance and gene flow

    Institute of Scientific and Technical Information of China (English)

    GUO Wei; SHEN Zuorui; LI Zhihong; GAO Lingwang

    2005-01-01

    The population genetics of the grain aphid Macrosiphum miscanti (Takahashi) is analyzed by microsatellite markers.Samples collected from 15 locations in China have been examined at 5 polymorphic microsatellite loci. Overall, genetic diversity displays a relation between the migration and gene flow in the grain aphid: a free and frequent gene flow is found in the eastern populations, and gene isolation occurs in the two western populations, especially Datong population and Guiyang population. The natural barriers may present an insurmountable obstacle preventing gene flow and aphid migration. However, a spatial genetic differentiation between populations is correlated with their geographical separation, indicating the geographic differentiation may play an important role in shaping the genetic structure of M. miscanti populations. In addition, most populations of grain aphids are out of Hardy-Weinberg equilibrium and there is heterozygote deficit. Based on F statistics, the average genetic differentiation among different geographical populations is relatively low. It seems that the long distance migration of the grain aphid may enhance gene flow and decrease genetic differentiation among different populations.

  14. Studies on groundwater flow and radionuclide migration at underground environments. Final report of collaboration research between JAERI and AECL

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Hiromichi; Nagao, Seiya; Yamaguchi, Tetsuji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    2001-01-01

    The Japan Atomic Energy Research Institute (JAERI) conducted a collaboration program Phase II with the Atomic Energy of Canada Limited (AECL) from 1994 to 1998. The program was started to contribute the establishment of safety assessment methodology for the geological disposal of high-level radioactive wastes on the basis of the results from the Phase I program (1987-1993). The Phase II program consisted of following experimental items: (1) radionuclide migration experiments for quarried blocks (1m x 1m x 1m) of granite with natural fracture under in-situ geochemical conditions at 240 m level of Underground Research Laboratory of AECL; (2) study on the effects of dissolved organic materials extracted from natural groundwaters on radionuclide migration; (3) study on groundwater flow using environmental isotopes at two different geologic environments; (4) development of groundwater flow and radionuclide transport model for heterogeneous geological media. The mobility of radionuclides was retarded in the fracture by the deep geological conditions and the fracture paths. The groundwater humic substances with high molecular size were enhanced for the mobility of radionuclides in the sand and granitic media due to the complexation. The application of {sup 36}Cl and {sup 129}I for the analysis on the long-term groundwater flow can be validated on the basis of investigation at the URL site. Moreover, the geostatistical model for the analysis on groundwater flow and radionuclide migration was developed, and was able to describe the groundwater flow and the migration of environmental tracers at AECL sites. This report summaries the results of the Phase II program between JAERI and AECL. (author)

  15. Analyzing the international exergy flow network of ferrous metal ores.

    Science.gov (United States)

    Qi, Hai; An, Haizhong; Hao, Xiaoqing; Zhong, Weiqiong; Zhang, Yanbing

    2014-01-01

    This paper employs an un-weighted and weighted exergy network to study the properties of ferrous metal ores in countries worldwide and their evolution from 2002 to 2012. We find that there are few countries controlling most of the ferrous metal ore exports in terms of exergy and that the entire exergy flow network is becoming more heterogeneous though the addition of new nodes. The increasing of the average clustering coefficient indicates that the formation of an international exergy flow system and regional integration is improving. When we contrast the average out strength of exergy and the average out strength of currency, we find both similarities and differences. Prices are affected largely by human factors; thus, the growth rate of the average out strength of currency has fluctuated acutely in the eleven years from 2002 to 2012. Exergy is defined as the maximum work that can be extracted from a system and can reflect the true cost in the world, and this parameter fluctuates much less. Performing an analysis based on the two aspects of exergy and currency, we find that the network is becoming uneven.

  16. Analyzing the International Exergy Flow Network of Ferrous Metal Ores

    Science.gov (United States)

    Qi, Hai; An, Haizhong; Hao, Xiaoqing; Zhong, Weiqiong; Zhang, Yanbing

    2014-01-01

    This paper employs an un-weighted and weighted exergy network to study the properties of ferrous metal ores in countries worldwide and their evolution from 2002 to 2012. We find that there are few countries controlling most of the ferrous metal ore exports in terms of exergy and that the entire exergy flow network is becoming more heterogeneous though the addition of new nodes. The increasing of the average clustering coefficient indicates that the formation of an international exergy flow system and regional integration is improving. When we contrast the average out strength of exergy and the average out strength of currency, we find both similarities and differences. Prices are affected largely by human factors; thus, the growth rate of the average out strength of currency has fluctuated acutely in the eleven years from 2002 to 2012. Exergy is defined as the maximum work that can be extracted from a system and can reflect the true cost in the world, and this parameter fluctuates much less. Performing an analysis based on the two aspects of exergy and currency, we find that the network is becoming uneven. PMID:25188407

  17. Internal and vorticity waves in decaying stratified flows

    Science.gov (United States)

    Matulka, A.; Cano, D.

    2009-04-01

    Most predictive models fail when forcing at the Rossby deformation Radius is important and a large range of scales have to be taken into account. When mixing of reactants or pollutants has to be accounted, the range of scales spans from hundreds of Kilometers to the Bachelor or Kolmogorov sub milimiter scales. We present some theoretical arguments to describe the flow in terms of the three dimensional vorticity equations, using a lengthscale related to the vorticity (or enstrophy ) transport. Effect of intermittent eddies and non-homogeneity of diffusion are also key issues in the environment because both stratification and rotation body forces are important and cause anisotropy/non-homogeneity. These problems need further theoretical, numerical and observational work and one approach is to try to maximize the relevant geometrical information in order to understand and therefore predict these complex environmental dispersive flows. The importance of the study of turbulence structure and its relevance in diffusion of contaminants in environmental flows is clear when we see the effect of environmental disasters such as the Prestige oil spill or the Chernobil radioactive cloud spread in the atmosphere. A series of Experiments have been performed on a strongly stratified two layer fluid consisting of Brine in the bottom and freshwater above in a 1 square meter tank. The evolution of the vortices after the passage of a grid is video recorded and Particle tracking is applied on small pliolite particles floating at the interface. The combination of internal waves and vertical vorticity produces two separate time scales that may produce resonances. The vorticity is seen to oscilate in a complex way, where the frecuency decreases with time.

  18. Internal migration, area effects and health: Does where you move to impact upon your health?

    Science.gov (United States)

    Green, Mark A; Subramanian, S V; Vickers, Daniel; Dorling, Danny

    2015-07-01

    Evidence surrounding the importance of neighbourhood on health has been mostly restricted to observational data analyses. However, observational data are often the only source of information available to test this association and can fail to accurately draw out casual effects. This study employs a pseudo-experimental design to provide a novel test for the evidence of neighbourhood effects on health, using migration as a mechanism for assessing the role of neighbourhood. Coarsened exact matching was employed on the British Household Panel Survey (2006-2008) to analyse the association between migration (by area type, measured using a classification of mortality patterns) and health. Although an overall significant positive association between migration and health was observed, once the effect was disaggregated by location and destination it disappeared. Rather, evidence of health selective migration was found whereby individuals of poorer health migrated to areas that displayed poorer health and social characteristics (and vice versa). Migration is an important process that through the social sorting of individuals in terms of their health, contributes to the growing polarisation and inequality in health patterns. The study helps to build upon previous research through providing a new and stronger form of analysis that reduces the influence of bias on results. Incorporating this under-utilised methodology and research design in future studies could help develop public health and geographical research. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Changes and Challenges in the Flow of International Human Capital: China's Experience

    Science.gov (United States)

    Pan, Su-Yan

    2010-01-01

    This article tracks the changes in the directions of the international flow of Chinese human capital between the 1870s and 2000s. Although many studies on international academic flow adopt the pull-and-push approach, this article argues that the direction of human capital flow is not determined solely by an individual's choice when faced with a…

  20. Route optimisation and solving Zermelo’s navigation problem during long distance migration in cross flows

    DEFF Research Database (Denmark)

    Hays, Graeme C.; Christensen, Asbjørn; Fossette, Sabrina

    2014-01-01

    not follow the optimum (Zermelo's) route. Even though adult marine turtles regularly complete incredible long-distance migrations, these vertebrates primarily rely on course corrections when entering neritic waters during the final stages of migration. Our work introduces a new perspective in the analysis...

  1. Flow-induced particle migration in microchannels for improved microfiltration processes

    NARCIS (Netherlands)

    van Dinther, A.M.C.; Schroën, C. G. P. H.; Imhof, A.; Vollebregt, H. M.; Boom, R. M.

    2013-01-01

    Microchannels can be used to induce migration phenomena of micron sized particles in a fluid. Separation processes, like microfiltration, could benefit from particle migration phenomena. Currently, microfiltration is designed around maximum flux, resulting in accumulation of particles in and on the

  2. Internal flow in droplets within a concentrated emulsion flowing in a microchannel

    Science.gov (United States)

    Leong, Chia Min; Gai, Ya; Tang, Sindy K. Y.

    2016-11-01

    Droplet microfluidics has enabled a wide variety of high-throughput biotechnical applications through the use of monodisperse micro-droplets as bioreactors. Previous fluid dynamics studies of droplet microfluidics have focused on single droplets or emulsions at low volume fractions. The study of concentrated emulsions at high volume fractions is important for further increasing the throughput of droplet microfluidics, but the fluid dynamics of such emulsions in confined microchannels is not well understood. This paper describes the use of microscopic particle image velocimetry to quantify the flow inside individual droplets within a concentrated emulsion having volume fraction φ ˜ 85% flowing as a monolayer in a straight microfluidic channel. The effects of confinement (namely, the number of rows of droplets across the width of the channel) and viscosity ratio on the internal flow patterns inside the drops at a fixed capillary number of 10-3 and a Reynolds number of 10-2 to 10-1 are studied. The results show that rotational structures inside the droplets always exist and are independent of viscosity ratio for the conditions tested. The structures depend on droplet mobility, the ratio of the velocity of the droplet to the velocity of the continuous phase. These values, in turn, depend on the confinement of the emulsion and the location of the droplets in the channel. Although this work presents two-dimensional measurements at the mid-height of the microchannel only, the results reveal flow patterns that are never described before in single drops or dilute emulsions.

  3. The Internal Migration and Spatial Redistribution of the Foreign-Born Population in the United States: 1965-70 and 1975-80.

    Science.gov (United States)

    Belanger, Alain; Rogers, Andrei

    1992-01-01

    Examines the importance of place of birth on the internal migration and spatial redistribution patterns of the foreign-born population in the United States for 1965-70 and 1975-80, relying mainly on the Public Use Microdata sample. Age patterns of migration are also analyzed for different groups. (SLD)

  4. Movements of Croatian Labour Supply and Their Implications on Migration Flows

    Directory of Open Access Journals (Sweden)

    Alka Obadić

    2008-06-01

    Full Text Available The Croatian labour market is characterised by a low degree of activity on the part of the population, a high unemployment rate, a pronounced problem with long-term unemployment and a high structural disproportion between supply and demand. Because of the relatively high share of the unofficial economy, there is a large difference between the administrative unemployment rate and that shown by surveys. Analysis of the situation on the Croatian labour market shows that significant structural issues still remained unsolved (such as inflexibility, mismatch between supply and demand with respect to profession and education, and similar. There is still very limited creation of new jobs. The employment rates of men and women and the employment of young people are among the lowest in comparison with the EU-27 and are far from attainment of the Lisbon objectives. The high rate of economic inactivity indicates the lack of utilisation of the existing work force potential. The conducted research shows that the continued advised needs for workers is 25 time higher than the annual number of approved work permits to foreigners from 1992 to 2006, while that number was negligible in 1991. Due to this situation, Croatia still has a very strict protectionist orientation towards employing foreigners, although the fact is that this situation will have to change very quickly with accession to the EU. It can be concluded that no major changes in migration flows or any significant shifts in em¬ployment and unemployment rates can be expected until the year 2010. Although opening the borders could mean, on the one hand, the possibility of increased emigration of the Croatian work force, the expectations are that such movements, nonetheless, will not occur. It is more likely that opening borders would be connected with greater mobility of workers, both from Croatia into other countries and from other countries towards Croatia.

  5. The importance of workforce surveillance, research evidence and political advocacy in the context of international migration of dentists.

    Science.gov (United States)

    Balasubramanian, M; Brennan, D S; Spencer, A J; Watkins, K; Short, S D

    2015-03-01

    The international migration of dentists is an issue of pressing significance that poses several complex policy challenges. Policy-making is mainly constrained by the lack of workforce surveillance, research evidence and political advocacy - all three are required to work together, yet with different purposes. We first discuss the inconsistencies in migrant dentist surveillance in major country-level governmental systems (immigration departments, dentist registration authorities and workforce agencies). We argue that the limitations in surveillance collections affect independent research and in turn scholarly contributions to dental workforce policy. Differences in country-level surveillance collections also hinder valid cross-country comparisons on migrant dentist data, impeding global policy efforts. Due to these limitations, advocacy, or the political process to influence health policy, suffers, but is integral to future challenges on dentist migration. Country-level advocacy is best targeted at improving migrant dentist surveillance systems. Research interest can be invigorated through targeted funding allocations for migration research and by improving the availability of dentist surveillance data for research purposes. At the global level, the WHOs global code of practice for international recruitment of health personnel (a crucial advocacy tool) needs to be strengthened. Global organisations such as the FDI World Dental Federation have an important role to play in advocating for improved migrant dentist workforce surveillance and research evidence, especially in low- and middle-income countries.

  6. Analysis of Migration Flows of the Population of the Vologda Oblast Districts

    Directory of Open Access Journals (Sweden)

    Mikhail Mikhailovich Panov

    2015-09-01

    Full Text Available The article presents the research on the main directions and scale of migration in municipal districts of the Vologda Oblast and considers the main types of migration and the specifics of their statistical accounting. The data by Rosstat served as a basis upon which a general analysis of migration dynamics in the Vologda Oblast districts was carried out; and the article presents its periodization. Three main periods are defined: the “migration shock” of 1991–1999 after the collapse of the Soviet Union, the migration stability of 2000–2008 and the post-crisis rural out-migration that began in 2009 and is increasing year by year. At the same time, gross migration indicators have shown high sensitivity to significant socioeconomic change, in particular, to the economic crises of 1999 and 2008. The article describes the main age and gender characteristics of migrants, it has been determined that the most active migrants are girls aged 15–29, who move from rural to urban settlements. In general, it is the young people aged 15–34 who are most likely to migrate. The author has found out that most of the Vologda Oblast districts are characterized by a higher outflow of the population, which is in some places restrained by a relative migration attractiveness of a number of areas. The author has found out that most districts of the Oblast are characterized by a higher outflow of the population, which is sometimes restrained by relative migration attractiveness of some areas. The author highlights the region’s territories with the highest migration attraction; in the long run they can play the role of “growth points” in the region; these territories comprise Velikoustyugsky and Chagodoshchensky districts, as well as several districts of the central part of the Vologda Oblast – Ust-Kubinsky and Vologodsky. The author also points out the territories that suffered the most from out-migration: Kichmengsko-Gorodetsky, Vashkinsky

  7. The impact of origin region and internal migration on Italian fertility

    Directory of Open Access Journals (Sweden)

    Michael White

    2007-12-01

    Full Text Available We examine the impact of population distribution on fertility in a nationally representative sample. We exploit detailed life-history data to conduct an event-history analysis of transition to first birth, examining mechanisms that might link migration and fertility: socialization, adaptation, selection, and disruption. Our multivariate analysis examines various socio-demographic traits, the place of birth, and interregional migration. Differences by region and migration stream are partly explained by compositional factors, such as female employment, union type, and education. The analysis presents much evidence for demographic selection and socialization and less for adaptation or disruption. The persistence of the region of origin differentials points to the continuing importance of the context.

  8. Old-Age Pension and Extended Families: How is Adult Children's Internal Migration Affected?

    Science.gov (United States)

    Chen, Xi

    2016-10-01

    This paper makes use of the most recent social pension reform in rural China to examine whether receipt of the pension payment equips adult children of pensioners to migrate. Employing a regression discontinuity (hereafter RD) design to a primary longitudinal survey, this paper overcomes challenges in the literature that households eligible for pension payment might be systematically different from ineligible households and that it is difficult to separate the effect of pension from that of age or cohort heterogeneity. Around the pension eligibility age cut-off, results reveal large and significant increase among adult sons (but not daughters) to migrate out of their home county. Meanwhile, adult children are more likely to migrate out if their parents are healthy. Our Fuzzy RD estimations survive a standard set of key placebo tests and robustness checks.

  9. Economy, Ethnicity and International Migration. The Comparison of Finland, Hungary and Russia

    Directory of Open Access Journals (Sweden)

    Annika Forsander

    2008-01-01

    Full Text Available The focus of this paper is to compare present migration situation, history, economy and migration regulation in an European Union country (Finland, and, an EU accessing country (Hungary and a major non - EU country (Russia. Our material and methods base on literature survey, policy analysis and analysis of the existing statistics and legislation. The results show that even in the era of globalisation that is often claimed to erode states regulatory power over the ? ows of capital and people, some regulatory power still exists. Instead of developing their policies in accordance with the largely self-regulating migration process, according to our data, the countries sought to regain political control through reproducing economic, ethnic and national hierarchies.

  10. NICCOLO MACHIAVELLI, THE BARON DE MONTESQUIEU AND THE DESTABILIZING EFFECTS OF INTERNATIONAL MIGRATION

    Directory of Open Access Journals (Sweden)

    William Barclay

    2017-01-01

    Full Text Available This essay demonstrates that, although modern liberals incessantly promote the EU as a living exemplar for the virtues of contemporary liberalism and basic, unrestrictive, migration policies, the experiences of innumerable contemporary EU states, such as France, contradict these spurious claims, since, instead of becoming enriched or improved, countless EU states have deteriorated and become fraught with social conflict, insecurity, and instability, as a result of their minimally restrictive, liberal, migration policies and consequent penetration with foreign, inherently contradictory ideology. Furthermore, this essay demonstrates that, despite the ignorant exclamations of modern liberals, the inviolable patriarch of liberalism, the Baron de Montesquieu, in addition to the pre-eminent, indispensable, paterfamilias of realism, Niccolo Machiavelli, explicitly confirm that, if any state fails to adequately restrict the migration of people and ideas across its borders, then that state will inevitably become penetrated by a foreign, inherently contradictory, ideology, and, consequently, eviscerated by an unrelenting insecurity.

  11. Flow Boiling and Condensation Experiment (FBCE) for the International Space Station

    Science.gov (United States)

    Mudawar, Issam; Hasan, Mohammad M.; Kharangate, Chirag; O'Neill, Lucas; Konishi, Chris; Nahra, Henry; Hall, Nancy; Balasubramaniam, R.; Mackey, Jeffrey

    2015-01-01

    The proposed research aims to develop an integrated two-phase flow boiling/condensation facility for the International Space Station (ISS) to serve as primary platform for obtaining two-phase flow and heat transfer data in microgravity.

  12. Solid rocket booster internal flow analysis by highly accurate adaptive computational methods

    Science.gov (United States)

    Huang, C. Y.; Tworzydlo, W.; Oden, J. T.; Bass, J. M.; Cullen, C.; Vadaketh, S.

    1991-01-01

    The primary objective of this project was to develop an adaptive finite element flow solver for simulating internal flows in the solid rocket booster. Described here is a unique flow simulator code for analyzing highly complex flow phenomena in the solid rocket booster. New methodologies and features incorporated into this analysis tool are described.

  13. [The southern border and international migration from the perspective of NAFTA].

    Science.gov (United States)

    Flores, C

    1993-01-01

    "Constitution of a trade bloc between Mexico, the United States and Canada through the North American Free Trade Agreement (NAFTA) in this decade has called attention to...the role of Mexico's southern border, Central American conflicts and migrations from that era. Relevant adjustments have been made to Mexico's policy in approaching problems regarding its southern neighbors. These changes respond largely to the perception held by larger economic blocs and migration generated by unequal development levels within these regions and countries." (SUMMARY IN ENG) excerpt

  14. Recovery Migration After Hurricanes Katrina and Rita: Spatial Concentration and Intensification in the Migration System.

    Science.gov (United States)

    Curtis, Katherine J; Fussell, Elizabeth; DeWaard, Jack

    2015-08-01

    Changes in the human migration systems of the Gulf of Mexico coastline counties affected by Hurricanes Katrina and Rita provide an example of how climate change may affect coastal populations. Crude climate change models predict a mass migration of "climate refugees," but an emerging literature on environmental migration suggests that most migration will be short-distance and short-duration within existing migration systems, with implications for the population recovery of disaster-stricken places. In this research, we derive a series of hypotheses on recovery migration predicting how the migration system of hurricane-affected coastline counties in the Gulf of Mexico was likely to have changed between the pre-disaster and the recovery periods. We test these hypotheses using data from the Internal Revenue Service on annual county-level migration flows, comparing the recovery period migration system (2007-2009) with the pre-disaster period (1999-2004). By observing county-to-county ties and flows, we find that recovery migration was strong: the migration system of the disaster-affected coastline counties became more spatially concentrated, while flows within it intensified and became more urbanized. Our analysis demonstrates how migration systems are likely to be affected by the more intense and frequent storms anticipated by climate change scenarios, with implications for the population recovery of disaster-affected places.

  15. Recovery Migration after Hurricanes Katrina and Rita: Spatial Concentration and Intensification in the Migration System

    Science.gov (United States)

    Fussell, Elizabeth; DeWaard, Jack

    2015-01-01

    Changes in the human migration systems of Hurricane Katrina- and Rita-affected Gulf of Mexico coastline counties provide an example of how climate change may affect coastal populations. Crude climate change models predict a mass migration of “climate refugees,” but an emerging literature on environmental migration suggests most migration will be short-distance and short-duration within existing migration systems, with implications for the population recovery of disaster-struck places. In this research, we derive a series of hypotheses on recovery migration predicting how the migration system of hurricane-affected coastline counties in the Gulf of Mexico was likely to have changed between the pre-disaster and the recovery periods. We test these hypotheses using data from the Internal Revenue Service on annual county-level migration flows, comparing the recovery period migration system (2007–2009) to the pre-disaster period (1999–2004). By observing county-to-county ties and flows we find that recovery migration was strong, as the migration system of the disaster-affected coastline counties became more spatially concentrated while flows within it intensified and became more urbanized. Our analysis demonstrates how migration systems are likely to be affected by the more intense and frequent storms anticipated by climate change scenarios with implications for the population recovery of disaster-affected places. PMID:26084982

  16. Cross-shelf transport of pink shrimp larvae: Interactions of tidal currents, larval vertical migrations and internal tides

    Science.gov (United States)

    Criales, Maria M.; Browder, Joan A.; Mooers, C.N.K.; Robblee, M.B.; Cardenas, H.; Jackson, Thomas L.

    2007-01-01

    Transport and behavior of pink shrimp Farfantepenaeus duorarum larvae were investigated on the southwestern Florida (SWF) shelf of the Gulf of Mexico between the Dry Tortugas spawning grounds and Florida Bay nursery grounds. Stratified plankton samples and hydrographic data were collected at 2 h intervals at 3 stations located on a cross-shelf transect. At the Marquesas station, midway between Dry Tortugas and Florida Bay, internal tides were recognized by anomalously cool water, a shallow thermocline with strong density gradients, strong current shear, and a high concentration of pink shrimp larvae at the shallow thermocline. Low Richardson numbers occurred at the pycnocline depth, indicating vertical shear instability and possible turbulent transport from the lower to the upper layer where myses and postlarvae were concentrated. Analysis of vertically stratified plankton suggested that larvae perform vertical migrations and the specific behavior changes ontogenetically; protozoeae were found deeper than myses, and myses deeper than postlarvae. Relative concentrations of protozoea in the upper, middle and bottom layers were consistent with a diel vertical migration, whereas that of postlarvae and myses were consistent with the semidiurnal tides in phase with the flood tide. Postlarvae, the shallowest dwellers that migrate with a semidiurnal periodicity, experienced the largest net onshore flux and larval concentrations were highly correlated with the cross-shelf current. These results provide the first evidence of an onshore tidal transport (a type of selective tidal stream transport, STST), in decapod larvae migrating in continental shelf waters offshore, ca. 100 km from the coast and at a depth of 20 m, while approaching the coastal nursery grounds. Longer time series would be necessary to establish whether internal tides play any role in the larval onshore transport of this species and determine if the STST is the dominant onshore transport mechanism.

  17. International migration of doctors, and its impact on availability of psychiatrists in low and middle income countries.

    Directory of Open Access Journals (Sweden)

    Rachel Jenkins

    Full Text Available BACKGROUND: Migration of health professionals from low and middle income countries to rich countries is a large scale and long-standing phenomenon, which is detrimental to the health systems in the donor countries. We sought to explore the extent of psychiatric migration. METHODS: In our study, we use the respective professional databases in each country to establish the numbers of psychiatrists currently registered in the UK, US, New Zealand, and Australia who originate from other countries. We also estimate the impact of this migration on the psychiatrist population ratios in the donor countries. FINDINGS: We document large numbers of psychiatrists currently registered in the UK, US, New Zealand and Australia originating from India (4687 psychiatrists, Pakistan (1158, Bangladesh (149, Nigeria (384, Egypt (484, Sri Lanka (142, Philippines (1593. For some countries of origin, the numbers of psychiatrists currently registered within high-income countries' professional databases are very small (e.g., 5 psychiatrists of Tanzanian origin registered in the 4 high-income countries we studied, but this number is very significant compared to the 15 psychiatrists currently registered in Tanzania. Without such emigration, many countries would have more than double the number of psychiatrists per 100,000 population (e.g. Bangladesh, Myanmar, Afghanistan, Egypt, Syria, Lebanon; and some countries would have had five to eight times more psychiatrists per 100,000 (e.g. Philippines, Pakistan, Sri Lanka, Liberia, Nigeria and Zambia. CONCLUSIONS: Large numbers of psychiatrists originating from key low and middle income countries are currently registered in the UK, US, New Zealand and Australia, with concomitant impact on the psychiatrist/population ratio n the originating countries. We suggest that creative international policy approaches are needed to ensure the individual migration rights of health professionals do not compromise societal population rights to

  18. Flow Visualization of Forced and Natural Convection in Internal Cavities

    Energy Technology Data Exchange (ETDEWEB)

    John Crepeau; Hugh M. Mcllroy,Jr.; Donald M. McEligot; Keith G. Condie; Glenn McCreery; Randy Clarsean; Robert S. Brodkey; Yann G. Guezennec

    2002-01-31

    The report descries innovative flow visualization techniques, fluid mechanics measurements and computational models of flows in a spent nuclear fuel canister. The flow visualization methods used a fluid that reacted with a metal plate to show how a local reaction affects the surrounding flow. A matched index of refraction facility was used to take mean flow and turbulence measurements within a generic spent nuclear fuel canister. Computational models were also made of the flow in the canister. It was determined that the flow field in the canister was very complex, and modifications may need to be made to ensure that the spent fuel elements are completely passivated.

  19. Carbon and Noble Gas Isotope Banks in Two-Phase Flow: Changes in Gas Composition During Migration

    Science.gov (United States)

    Sathaye, K.; Larson, T.; Hesse, M. A.

    2015-12-01

    In conjunction with the rise of unconventional oil and gas production, there has been a recent rise in interest in noble gas and carbon isotope changes that can occur during the migration of natural gas. Natural gas geochemistry studies use bulk hydrocarbon composition, carbon isotopes, and noble gas isotopes to determine the migration history of gases from source to reservoir, and to trace fugitive gas leaks from reservoirs to shallow groundwater. We present theoretical and experimental work, which helps to explain trends observed in gas composition in various migration scenarios. Noble gases are used as tracers for subsurface fluid flow due to distinct initial compositions in air-saturated water and natural gases. Numerous field studies have observed enrichments and depletions of noble gases after gas-water interaction. A theoretical two-phase gas displacement model shows that differences in noble gas solubility will cause volatile gas components will become enriched at the front of gas plumes, leaving the surrounding residual water stripped of dissolved gases. Changes in hydrocarbon gas composition are controlled by gas solubility in both formation water and residual oil. In addition to model results, we present results from a series of two-phase flow experiments. These results demonstrate the formation of a noble gas isotope banks ahead of a main CO2 gas plume. Additionally, we show that migrating hydrocarbon gas plumes can sweep biogenic methane from groundwater, significantly altering the isotope ratio of the gas itself. Results from multicomponent, two-phase flow experiments qualitatively agree with the theoretical model, and previous field studies. These experimentally verified models for gas composition changes can be used to aid source identification of subsurface gases.

  20. Characteristics of Migration Flows and Integration of New Immigrant Groups in the Labour Market in Southern European EU Member States

    Directory of Open Access Journals (Sweden)

    Snježana Gregurović

    2011-04-01

    Full Text Available In the early 1990s, and especially after the accession to the European Union, southern European countries were faced with an increased influx of immigration, particularly by third country citizens. The majority of migration flows refers to illegal migration. In this paper, the integration of new immigrant groups in the labour market has been analysed by using the theory of the segmented labour market. A high degree of labour market segmentation and irregularities in the analyzed countries is particularly present in the construction, agricultural and service sectors (households, hotels and catering. Illegal recruitment is an important attractive factor for illegal migrants, and encourages the development of illegal migration. Frequent implementation of control programmes solves the problem of illegal migrants only partially while, at the same time, an increasing number of new immigrants is being “attracted”. Due to special features of more recent migration flows in southern European countries, it is possible to apply the “South European immigration model” by King and Ribas-Mateos, portraying these flows triangularly. In this model the mass influx of immigration is connected to a high level of irregularities in the economic sector and a weak welfare state. The uneven economic development of sending and receiving countries, as well as the perception of new immigrants (third country citizens exclusively through the prism of homo economicus, does not inspire too much optimism that their position in the labour market and in society will significantly improve in the foreseeable future. On behalf of more equitable treatment of new immigrant groups, their greater recognition should be demanded from receiving countries’ governments as well as the regulation of their position by introducing new and different norms and standards, based in the first place on universal human rights.