Migration Tendencies Research Articles

Genomic analysis of a reef-building coral, Acropora digitifera, reveals complex population structure and a migration network in the Nansei Islands, Japan.

Understanding the structure and connectivity of coral populations is fundamental for developing marine conservation policies, especially in patchy environments such as archipelagos. The Nansei Islands, extending more than 1000 km in southwestern Japan, are characterized by high levels of biodiversity and endemism, supported by coral reefs, which make this region ideal for assessing genetic attributes of coral populations. In this study, we conducted population genomic analyses based on genome-wide, single-nucleotide polymorphisms (SNPs) of Acropora digitifera, a common species in the Nansei Islands. By merging newly obtained genome resequencing data with previously published data, we identified more than 4 million genome-wide SNPs in 303 colonies collected at 22 locations, with sequencing coverage ranging from 3.91× to 27.41×. While population structure analyses revealed genetic similarities between the southernmost and northernmost locations, separated by >1000 km, several subpopulations in intermediate locations suggested limited genetic admixture, indicating conflicting migration tendencies in the Nansei Islands. Although migration networks revealed a general tendency of northward migration along the Kuroshio Current, a substantial amount of southward migration was also detected, indicating important contributions of minor ocean currents to coral larval dispersal. Moreover, heterogeneity in the transition of effective population sizes among locations suggests different histories for individual subpopulations. The unexpected complexity of both past and present population dynamics in the Nansei Islands implies that heterogeneity of ocean currents and local environments, past and present, have influenced the population structure of this species, and similar unexpected population complexities may be expected for other marine species with similar reproductive modes.

Tersine Göç Eğilimi ve Diaspora Ağları: Almanya'daki Yüksek Nitelikli Türklerin Tersine Göç Eğilimlerini Etkileyen Faktörler

The study aims at revealing the remigration trends of the skilled Turkish immigrants in Germany especially towards Turkey by examining international emigrational trends and the factors that cause these trends. In this context of study, a field of study was carried out between the period of 15/11/2018 and 30/04/2019, and 1,127 participants, 451 students (40%), and 676 graduates (60%) were reached across Germany under the fieldwork. The logistic regression analysis was used to analyze the data via regression coefficients when interpreting continuous variables. Additionally, Odds Ratio (OR) values were used while interpreting categorical variables and so the differences between reference categories were revealed. According to the results of the research, the immigrants who cannot economically integrate into the country of immigration and face negative situations such as xenophobia while looking for a job and tend to return to their countries. The return trend of immigrants who try to follow the developments in their countries, which keep their relations with their countries strong, is higher than the other immigrants. In addition, there are differences for the evaluation of sociopolitical conditions besides international migration tendencies of immigrants who complete socialization process in their own country and those who end this process in the immigrant country.

Evaluation of agricultural policies implemented with respect to less favoured area’s: evidence from Turkey

There have been many different agricultural support tools varying by countries. These agricultural support tools are determined according to different indicators such as the policies, expectations, regions, and economic levels of the countries and may differ from each other. One of these agricultural support tools is Less Favoured Area (LFAs) that has been applied for a long time. Turkey has many geographically different regions and many different agricultural support tools like those in the other counties However, considering the EU full membership process policies, a specified support tool for the LFAs, which are widely used in the EU, has not been implemented in Turkey. Mersin province is one of the areas where that is an issue and so was selected for this study. The province has a dual structure, with high mountains (Taurus) and wide plains. People in the mountainous areas make a living from animal production, especially goat breeding. The study framework was based on the logistic regression model, which was compared farmers' descriptive statistics and socio-economic features in villages in the mountainous/semi-mountainous areas and on the plains of Mersin province. Farmers’ intentions for land allocation and livestock and their migration tendencies were analysed in different scenarios. Age, experience, number of small ruminants, land size and credit usage were found to have a statistically significant effect on farmers’ decisions about continuing farming. Their decisions changed across the policy scenarios provided, and a policy that considers regional differences was found to be significant in their decisions. The paper shows agricultural support policies should consider regional differences to compensate for income losses due to physical conditions.

Mobility trends in Psychiatry trainees: an Italian perspective.

Psychiatry has been affected by the 'Brain Drain' phenomenon for decades, with professionals usually migrating from lower- to higher-income countries. Whilst Italy faces a decreasing Psychiatric workforce in the near future, little is known about the factors that influence migration of Psychiatry trainees in Italy. To explore the migration tendencies of Psychiatry trainees training in Italy. A cross-sectional survey was disseminated to Psychiatry trainees in Italy. The vast majority (84.2%) of the trainees had 'ever' considered leaving Italy, and more than half (60.4%) considered leaving the country 'now'. Only a quarter (25.3%) had taken 'practical steps' towards migration. Male trainees were more likely to have 'ever' considered leaving Italy. Trainees without children were more likely to have 'ever' considered leaving and more likely to consider leaving 'now'. More southern Italian trainees were considering leaving the country 'now' compared to those from the centre-north. 'Academic' and 'work' reasons were the two most cited factors given both as a reason for wanting to leave Italy and as conditions that should be improved in the country. The main reason cited to remain in the country was personal. Several Psychiatry trainees in Italy consider migration as a possibility, mainly driven by work and academic reasons. The main factor keeping trainees in Italy was personal reasons. Highlighting the reasons why trainees leave is crucial to facing these issues and either finding ways to encourage trainees to remain or finding other solutions for the medical shortage.

Doping Process of 2D Materials Based on the Selective Migration of Dopants to the Interface of Liquid Metals

The introduction of trace impurities within the doping processes of semiconductors is still a technological challenge for the electronics industries. By taking advantage of the selective enrichment of liquid metal interfaces, and harvesting the doped metal oxide semiconductor layers, the complexity of the process can be mitigated and a high degree of control over the outcomes can be achieved. Here, a mechanism of natural filtering for the preparation of doped 2D semiconducting sheets based on the different migration tendencies of metallic elements in the bulk competing for enriching the interfaces is proposed. As a model, liquid metal alloys with different weight ratios of Sn and Bi in the bulk are employed for harvesting Bi2 O3 -doped SnO nanosheets. In this model, Sn shows a much stronger tendency than Bi to occupy surface sites of the Bi-Sn alloys, even at the very high concentrations of Bi in the bulk. This provides the opportunity for creating SnO 2D sheets with tightly controlled Bi2 O3 dopants. By way of example, it is demonstrated how such nanosheets could be made selective to both reducing and oxidizing environmental gases. The process demonstrated here offers significant opportunities for future synthesis and fabrication processes in the electronics industries.

THE IMPACT OF REGIONAL INEQUALITY ON MIGRATION TRENDS IN LATVIA

The topic of current research and key findings are topical, taking into the consideration the territorial development tendencies of Latvia, which is characterized by the long-term regional inequalities and the tendencies of the migration of the population. The aim of the research is to analyse the impact of the regional inequalities on the migration tendencies of population in Latvia. The following research methods have been used in the research- logically constructive method, content analysis, monographic method, synthesis method, statistical analysis of interrelations, integral index method. Within the research, by using the selected research methods, authors have evaluated the influence of migration indicators-stimulators and indicators-de-stimulators on the migration trends in Latvia over time.

IMPACT OF COVID-19 ON EXTERNAL LABOR MIGRATION OF UKRAINIANS

According to the International Labor Organization (ILO), there are about 164 million migrant workers in the world. This shows that the main motive for the migration movement is job search. About three-quarters of all migrant labor flows come from high-income countries, where one in six workers is an immigrant. Conversely, the highest level of emigration is from those areas that have a high level of poverty and virtually no social protection. The spread of the coronavirus has led to the rapid closure of national borders, and the vast majority of migrant workers have found themselves without income and in difficulty, prompting the ILO to call the situation a “crisis within a crisis.” The COVID-19 pandemic has had a negative impact on migrant workers, regardless of their job status and qualifications. While workers in the hotel and restaurant and retail sectors lost their jobs, those employed in health care and agriculture, on the contrary, were in demand and at risk of infection. Thus, the pandemic has sharply exacerbated the scale, degree of risk and uncertainty inherent in migrant workers, leading to even greater vulnerability. The article examines the impact of COVID-19 on the scale of external labor migration of Ukrainians and its economic and social consequences for the country. The peculiarities of international labor migration in the conditions of COVID-19 are clarified and probable prospects of transformation of migration tendencies are determined. Most migrants are currently in a state of uncertainty. On the one hand, they are temporarily cut off from foreign earnings, on the other hand, even in conditions of impossibility of migration, they are not interested in vacancies offered on the labor market of Ukraine. Based on the above study, we can conclude that most likely in the near future the volume of emigration will remain at the current level, and if the economic downturn continues, the number of emigration flows from Ukraine will increase.

The Challenges of Climate Change forMigration

Nowadays, when we want to describe environmental conditions, terms like air, water and soil pollution, melting glaciers, devastating drought, rising sea levels, population problems or the decrease of biodiversity are among the first ones to come up. The environment has always been a driver of migration. The estimation on the total number of environmental migrants due to global factors such as population growth, poverty, governance, human security and conflict, which have a huge impact, is quite challenging. As for the predictions, this amount may range from 25 million to one billion by the year 2050.2 Europe has become one of the most important immigration destinations in recent decades, and migratory pressures are increasing. Furthermore, the continent is affected not only by external exodus, but also by internal migration, as a result of environmental degradation, which can also be observed there, further accelerating the process of internal migration. The immigration policies of most destination countries are not conducive to receiving large numbers of environmental migrants, unless they enter through already existing admission categories. Thus typically, the purpose of the residence is employment, education and family reunification, but what about the people who had to leave their homes because of the environmental degradation? During the coronavirus pandemic economic activity slowed down, causing a reduction in carbon emissions, but due to the constant deterioration of the environmental conditions there are a lot of discussions about the term sustainable development. The aim of this study is to demonstrate how climate change has a major role to play in the migration tendencies, as it may amplify the existing political, social or economic problems. Discussing this topic, it is inevitable to use the term environmental refugee. After an overview of the relevant scientific literature, the author looks for the answer to the question whether there have been any changes in the regulations since the introduction of this concept.

The role of Poland's eastern border in global migration systems

While Poland has been perceived as a country that mainly receives migrants from the neighbouring Eastern Europe, it is also increasingly now representing an attractive place to work or study for migrants from other countries completely foreign from Poland in terms of their language and culture. However, as data on such international migrations are affected by numerous errors but can be supplemented by long-term statistics on border traffic, the work detailed here has sought: (a) to evaluate longterm trends to the structure of foreign traffic incoming across the country’s eastern border; (b) to identify causes of change in the composition of incoming cross-border traffic in terms of nationality, in relation to the geopolitical situation (pertaining both in Europe and the countries of origin); (c) to define the roles particular sections of Poland’s eastern border play in the migration-pressure context. The study was based on statistical data for the period 1994-2019 obtained from the Polish Border Guard. In an effort to encapsulate current migration tendencies, particular attention was paid to the citizens of Syria, Somalia, Nigeria, Iraq, Bangladesh and India. However, analysis also extended to the inflow of citizens of relatively closer migration origin, i.e. from countries like Moldova, Georgia, Armenia and Kazakhstan. In the period under investigation, Poland’s eastern border was found to have been subject to the impact of economic factors (influencing cross-border traffic), while also – over time – becoming ever-more susceptible to geopolitical events (e.g. the crisis in Ukraine and the migration crisis in Europe as a whole). Significant growth was to observed, not only (obviously) in numbers incoming from neighbouring countries, but also where other, non-European countries were concerned. Looked at long-term (over the last 30 years), Poland’s eastern border can be seen to have changed in nature several times, transcending local status in favour of global, but also moving in the opposite direction.

Alloying induces directionally-dependent mobility and alters migration mechanisms of faceted grain boundaries

Faceted grain boundaries exhibit unusual segregation and migration tendencies. To gain a deeper understanding of how solute atoms interact with faceted interfacial structures during migration, this study probes the migration behavior of a faceted Σ11 boundary in Cu doped with Ag atoms. The solutes are found to segregate to the facet with more free volume and strongly reduce boundary velocity in one migration direction, but not the other, due to the presence of a directionally-dependent motion mechanism that can escape solute pinning and therefore speed up migration. Hence, a new mechanism of chemically-induced anisotropy in grain boundary mobility is uncovered by these simulations.

Correlation between bonding, vacancy migration mechanisms, and creep in model binary and ternary hcp-Mg solid solutions

High temperature creep deformation of hcp-Mg alloys is dominated by dislocation climb driven by out-of-plane (OOP) vacancy migration. Past experiments and atomistic simulations have indicated that Zn addition reduces vacancy migration tendencies and improves creep resistance. Here, we have compared in-plane (IP) and out-of-plane (OOP) vacancy migration mechanisms in binary Mg–X (Ca, Y, and Gd) and ternary Mg–X (Ca, Y, and Gd)–Zn alloys using density functional theory based first principles computations. Irrespective of Zn addition, the migration barrier for OOP diffusion was consistently higher than IP in our prototype binary and ternary alloys. The presence of Zn in ternary systems, however, substantially increases the OOP activation barrier relative to binary alloys. The higher OOP barrier in Mg–X–Zn was attributed to favorable local relaxation, enhanced charge localization, higher interplanar bond stiffness, and greater s orbital electron occupancy in the peak saddle state. Combined, these factors restrict non-conservative dislocation climb by impeding out-of-plane vacancy movement and improve the creep resistance of ternary Mg–X (Ca, Y, and Gd)–Zn alloys.

DYNAMICS OF ATTITUDES OF POPULATION LIVING IN THE ALTAI KRAI TOWARDS INTER-ETHNIC RELATIONS AND MIGRATION SITUATION IN THE REGION

Migration issues are today one of most discussed and acute. Attention towards migration processes increases with its growing magnitude and consequences, having positive and negative character. International migration has acquired greater prominence in border regions of Russia where it become related to inter-ethnic relations. The article presents the results of a multi-year sociological survey (2016-2020, n = 6250), aimed at studying the migration situation and the social integration of representatives of different ethnic groups living in the Altai region. Especially, attitudes of population towards migration, migrants and migration policy, ethnic relations, tendencies and different aspects of changes in these attitudes are in the focus of the analysis.

Estimation and prediction of the oscillation pattern of meandering geometry in a sub-catchment basin of Bhagirathi-Hooghly river, West Bengal, India

Meandering is the winding curve or bends in a river within the floodplain area. Though it is a natural process, it affects the populace by the resultant effect of lateral migration with bank erosion in the floodplain area. The present sub-catchment basin (Nabadwip–Kalyani stretch) of the Bhagirathi-Hooghly river is a vital lifeline of southern West Bengal, which offers adequate water for irrigation, industrialisation, and human habitation. This region is experiencing a favourable geomorphic change through river bank line changing with bank erosion and sinuous meandering. Illegal sand mining and monsoonal flood enhances the meandering process and triggers the reduction of settlement and cropland. The present study elaborates on the migration tendencies and meandering geometry of this zone and tries to predict the future river centerline position in a sinuous course. The study area is divided into 30 cross-sections, which reveals the increasing trend of lateral migration and erosion behaviour towards the eastward section of this region. The spatial and temporal shifting of river centerline and resultant migration observes and predicts through the migration coefficient approach (Hasegawa in Proceedings of the Hokkaido Branch, Japan Society of Civil Engineering, pp 197–202, 1977; Ikeda et al. in J Fluid Mech 112:363–377, 1981. https://doi.org/10.1017/S0022112081000451 ; Motta et al. in Geomorphology 163–164:10–25, 2012. https://doi.org/10.1016/j.geomorph.2011.06.036 ) by Arc GIS v 9.3.1. This model indicates the trend of channel width decreasing, with increasing near bank velocity in the crescent of meandering bend in future. The simulated and predicted centerline validates by positive linear relation (R2) and lowest RMSE value in few cross-sectional areas. The oscillation character of meander signifies the amount of discharge in the sub-catchment basin. The unpredictable behaviour of the migration shows a rapid change of meandering geometry through the increasing nature of bank erosion possibilities with peak discharge during monsoon. The study predicts future centerline of the meandering channel and the information on river migration, which will contribute to the plan on bank erosion and denote the vulnerable zonation.

An econometric analysis of Hispanic migration in the United States

ABSTRACT This paper investigates the spatial redistribution pattern of Hispanics driven by internal migration tendencies in the United States, using American Community Survey (ACS) Public Use Microdata Sample (PUMS) data. We formulate three econometric models to study the internal migratory behaviour of Hispanics. More importantly, to uncover potential congestion and spillover effects, we introduce a novel variable into migration research, namely, the Neighbouring Hispanic Community. Our findings indicate that domestic migration of Hispanics leads to agglomeration of Hispanics, with the strongest agglomeration occurring in the states bordering the most concentrated states. While the congestion effect tends to weaken the agglomeration in the most concentrated states, the Hispanic-sparse states do not tend to receive Hispanics. The underlying force of potential dispersion is congestion and spillover from the highly concentrated states to their nearby states. Incorporating personal attributes into the analysis has provided some support for the spatial assimilation theory.

Earthquake Migration and Hidden Faults in the Priamurye Region

The detection of tectonic fracturing zones in the form of hidden faults, which are not exposed at the surface but are capable of generating intense seismic oscillations and causing hazardous geological phenomena, is a vital problem to be solved in the Priamurye region. We propose a comprehensive approach following which the earthquake migration data are taken as a basis for the detection of hidden faults, while the geophysical and morphostructural data are involved as the additional information for validating the obtained results. In our study, we detail the earthquake migration tendencies and estimate the migration direction and velocity. Based on these data, tectonic fracturing zones are identified and the hidden faults and their segments where persistent earthquake migration is manifested are revealed in the Priamurye region. The data that establish the direction and velocity of the earthquake epicenter migration will provide forecasting and assessment of natural hazards in the Priamurye region.

Attitudes towards migration from the eastern coast of the Baltic Sea: similar history but different psychiatric trainees?

This article aimed to describe and compare migration tendencies between junior doctors training in psychiatry in the Baltic countries. A cross-sectional survey was circulated in Estonia, Latvia and Lithuania in 2013–2014 as part of the Brain Drain study. The 61-item, anonymous questionnaire covered participants’ demographic data, experiences of short-term mobility, long-term migration and trainees’ attitudes towards migration. In this sample (n = 95) of psychiatric trainees in the Baltic countries, the majority were female (79.1%), training in adult psychiatry (77.9%). A vast majority (87.0%) of psychiatric trainees in the Baltic countries have ‘ever’ considered leaving the country; almost half (in Estonia) or more than a half (in Lithuania and Latvia) were considering leaving ‘now’; yet a minority took ‘practical steps’ towards migration. For all trainees in the Baltic states, personal reasons were the most important to stay in their country. Whilst regarding reasons to leave, financial was top in Lithuania, while trainees from Estonia and Latvia indicated personal reasons as key to emigrate. Several psychiatric trainees in the Baltic countries had considered migration, with many calling for improvements in their salaries. These findings call for further investigation and action to support the workforce in the Baltics.

Migration kinetics of fluorescent whitening agents from polyethylene food packaging to food simulants

The fluorescent whitening agents (FWAs) could be used in polyethylene (PE) packaging to increase whiteness, little work is done to explore the pollution form PE additives to food. Therefore, this study investigated the migration of FWAs from PE food packaging to a fatty food simulant (corn oil) and aqueous ethanol food simulant. Using the determined migration data, both a Crank monolayer migration model based on Fick’s second law and a Weibull migration model were established for the FWAs. We compared the applicability of the two models to the migration tendencies of the FWAs. Both models could describe the migration behaviors of the FWAs into corn oil, the Weibull model predictions were closer to the actual migration trends. The migration behaviors of the FWAs into 95% ethanol could only be described by Crank model. In the Weibull model, the values of the parameters τ and β were positively correlated with temperature and negatively correlated with the thickness of the food packaging. In the Crank model, the partition coefficient values were positively correlated with the boiling points and negatively correlated with the polarity values. The storage conditions of the food including temperature, the thickness of PE had a tremendous impact on the migration of the FWAs in the PE. We hope this study can promote a deeper understanding of additive pollution from packaging materials to food.

Compensatory growth offsets poor condition in native trout populations

Abstract Compensatory growth—when individuals in poor condition grow rapidly to catch up to conspecifics—may be a mechanism that allows individuals to tolerate stressful environmental conditions, both abiotic and biotic. This phenomenon has been documented fairly widely in laboratory and field experiments, but evidence for compensatory growth in the wild is scarce. Cutthroat trout (Oncorhynchus clarkii subsp.) are cold‐water specialists that inhabit montane streams in western North America where seasonal conditions can be harsh and growth rates vary greatly among seasons. Understanding if individuals compensate for periods of reduced growth and body condition will improve understanding of the requirements of fish throughout their life‐cycle and across freshwater habitats. We quantified compensatory growth of juvenile cutthroat trout using extensive mark–recapture data from 11 stream populations (1,125 individuals) and two subspecies inhabiting a wide range of ecological settings in the northern Rocky Mountains, U.S.A. Our objectives were to determine how growth was linked across seasons and whether individuals behaviourally compensated for depressed body condition via emigration. Fish in relatively poor condition consistently demonstrated compensatory growth in mass during subsequent seasons. In contrast, fish in relatively better condition responded with positive growth in length during the summer signalling these fish may be better suited to headwater environments; no compensatory growth in length was found during the winter. Furthermore, there was no evidence that individual condition mediated migration tendencies of fish to seek more favourable habitat. Across a wide range of environmental conditions, we found consistent empirical support for compensatory growth in mass in the wild. A critical next step is to quantify how changing abiotic and biotic conditions influence the ability of stream fishes to compensate for locally or seasonally challenging conditions, thereby affecting long‐term resiliency, viability, and adaptation in the face of changing environmental conditions.

THE EVOLUTION OF MIGRATION: THE CASE OF COASTAL SANDY ZONE IN THUA THIEN HUE PROVINCE, VIETNAM

By using the baseline data of Hao (2009) with 110 households, this study aimed to evaluate migration tendencies, reasons for migrations, contributions of migration and the factors affecting immigration waves. Two types of models were used, the Difference and Differences method applied to carry out the change of total income caused by the decision to migrate; the logistic models applied to identify the factors affecting on migration decision of household. The results showed that migration had a vital role in livelihood outcome and the positive trends in migration issues included diversification of jobs, higher level of education and higher wage for migrants. From the research findings and the problem statements, some well-orientated policies need to be focused on taking advantage of migration issues and reducing its negative impacts in the long term (Deshingkar, 2006; Paes Herrera et al.

Use of Citizen Science Data for Characterizing Patterns and Drivers of Avian Altitudinal Migration

Altitudinal migration, the seasonal and repeateing movement of animal individuals between breeding and non-breeding areas at different elevations, is a common and important but understudied behavior in birds. Difficulty in characterizing avian altitudinal migration has prevented a comprehensive understanding of both patterns and drivers of this behavior. To fill this knowledge gap, we investigated altitudinal migration patterns and underlying mechanisms for a major proportion (~70%) of an entire resident bird community on a subtropical island with an almost 4000-m elevational gradient. We quantified migration tendency of individual bird species based on the seasonal shift in the elevational distribution of their occurrence records in the eBird database. We then built phylogeny-controlled regression models to examine the associations between the birds’ migration tendencies and their functional traits to test major hypotheses on the mechanisms of altitudinal migration. The results showed a common but variable altitudinal migration behavior among the 118 species examined, with 40 and 11 species conducting post-breeding downhill and uphill migration, respectively. The species that have a narrower thermal tolerance range, can tolerate lower temperatures, have a smaller body size, have a more diverse or invertebrate-rich diet, or use an open nest had a higher downhill migration tendency. In contrast, no traits examined showed consistent associations with the uphill migration tendency. This suggests that post-breeding downhill and uphill migrations are driven by different processes and current hypotheses can only explain the former, but not the latter. This relatively comprehensive study demonstrated the power of citizen science data to provide new insights into an old research question from a novel perspective. Using the same approach, we are investigating the behavior in mountain regions around the world. With the global analysis, we will be able to understand the general patterns and mechanisms of avian altitudinal migration and also investigate their variation among mountain regions in different climate zones. In the face of rapid environmental changes in mountain ecosystems, the approach used in this study may also provide essential information for the conservation of mountainous biodiversity.