Migration Patterns Research Articles

The Impact of Artificial Barriers on the Varuna litterata Migration Route in the Lower Serayu River, Central Java and Its Molecular Identification

The Serayu River is one of the longest rivers in Central Java. Dams built in the lower reaches of the Serayu River are thought to block the migration paths of fish and aquatic macrocrustaceans. This study aimed to determine the effect of dam on Varuna litterata migration and its molecular identification. This research was conducted using the observation method. Migration observations were made on vertical paths while molecular identification of V. litterata in the lower reaches of the Serayu River was compared with existing data in GenBank. The study covered the freshwater area above the Serayu Dam, the open area with freshwater below the Serayu Dam, and the open area with brackish water at the estuary of the Serayu River, with a study length of 33.37 km. The results showed that the presence of dams in the lower reaches of the Serayu River inhibited the migration pattern of V. litterata. The vertical shape of the dam causes only a few V. litterata to migrate to the top of the dam. The dam in the lower reaches of the Serayu River resulted in not many V. litterata being able to migrate to the top of the dam, so there were very few V. litterata found in the population upstream of the dam (115 ind). The results of molecular identification of V. litratata using the cytochrome C oxidase subunit I (COI) gene show that this crab is 100% the same as the data in GenBank and is closely related to Varuna yui and other Varunidae crab species.Keywords: Dams, Molecular, Migration, Serayu River, Varuna litterata

Sensitivity of development goals to water scarcity of Iraq and transboundary regions

Iraq and its transboundary regions have significant challenges from water scarcity in combination with other social and environmental factors. There are short- and long-term implications for vulnerable demographics, such as youth. With Iraq's dependence on upstream water management, there is a need to address several critical factors of transboundary watersheds such as the Haditha, Mosul, Dokan, and Euphrates-Tigris basin. This paper develops the use of particular social, hydrological, and other environmental factors in a risk register of basins and vulnerable populations, where societal priorities vary across scenarios of hydrology and water. Social data (i.e., gridded youth population data) and hydrological observations (i.e., precipitation, temperature, root zone soil moisture, and Normalized Difference Vegetation Index (NDVI)) are obtained from publicly available satellite-based Earth observations and global models. Risk is defined and quantified as the disruption of basin order and spatial plots are provided to improve understanding of the spatial distribution of water scarcity challenges in the region with regard to vulnerable populations. The results feature identification of the most and least disruptive scenarios including: 1) population density is lowest in basins exposed to the highest air temperatures, 2) an urban-to-rural migration pattern (such as prompted by a public health crisis) would significantly disrupt basin order, and 3) populations with greatest exposure to extreme hydrological conditions of water scarcity are found in the southern basins of Iraq in or near the Al-Muthanna governorate. The impacts of this work are to steer future investments that mitigate risk of disrupted system orders and to increase system resilience of vulnerable populations to water scarcity.

Industrial robot applications and individual migration decision: evidence from households in China

The integration of industrial robot application (IRA) into various sectors has catalyzed significant transformations in the labor market, reshaping the dynamics of individual migration decision (IMD). As industries increasingly adopt automation, the implications for workforce distribution and migration patterns become critical areas of study. Based on the conditional logit model and using CMDS data, this paper explores the relationship between IRA and IMD, as well as the heterogeneity effect and influencing mechanism. The findings indicate that IRA reduces the probability of the floating population choosing the city, and the results are robust after considering endogeneity and further robustness test. The impact of IRA on IMD is heterogeneous. Relatively speaking, the floating population with high education levels, health, younger, unmarried, female, agricultural household registration, state-owned enterprises, and non-routine task work does not over-think the impact of IRA during the migration process. In addition, the floating population also considers geographical location, city size, marketization level, wage level, and environmental quality when making migration decisions. the mechanism test shows that IRA attracts or suppresses the floating population through factors such as wage levels, housing price level, difficulty in finding a job, etc., depending on the result of individual utility maximization. These insights reveal the complex interplay between technological advancements in robotics and labor migration, emphasizing the need for comprehensive policy frameworks to manage these transformations effectively.

Evaluating the Role of GDP Per Capita in Shaping Internal Migration Patterns in China: A Spatial Econometric and Regression Analysis Approach

Evaluating the Role of GDP Per Capita in Shaping Internal Migration Patterns in China: A Spatial Econometric and Regression Analysis Approach

Effect of environmental drivers on the spatiotemporal distribution of mackerel at age in the Nordic Seas during 2010−20

Abstract A joint spatio–temporal distribution model of mackerel (ages 3–10) was developed to investigate the age-based responses of mackerel to three environmental drivers: sea surface temperature (SST), mixed layer depth, and chlorophyll-a concentration during the summer months 2010–20 in the Nordic Seas. The study showed that SST was the most important variable amongst the ones tested and had the strongest impact on the distribution of the younger age classes (3–5), which had a narrower range of favourable SST and a stronger aversion to cold temperatures than older individuals. Consequently, the impact of SST differed regionally; in the polar front regions, SST explained up to 61% of the variability in the observed density of young individuals, where Arctic water masses likely acted as a barrier to these young individuals. That said, part of it could be confounded with the limited migration capability of young mackerels, which could not reach the furthest frontal regions. In warmer southern waters, the same environmental variables had less explanatory power for mackerel of all ages. Individuals in the south were likely not constrained by temperature and perhaps more influenced by other variables, such as food availability or ocean current (throughout their migration path), for which appropriate data are lacking. Moreover, the model showed that older mackerel were distributed more to the north and west, and their migration pattern changed when the 2013 year-class no longer migrated to the west compared to previous year-classes. Additionally, all-year classes started migrating more eastward from summer 2018.

Glenoid wear and migration pattern of a humeral head resurfacing implant: a prospective study using radio stereometric analysis

Background and purposeThe humeral head resurfacing arthroplasty (HHR) is normally used as a hemi shoulder arthroplasty and has been in use for the treatment of Gleno-Humeral osteoarthritis of the shoulder (OA) for more than 30 years. Some studies, however, shows that anatomical total shoulder arthroplasty provides better improvement in function than a HHR for patients with OA. Reasons for this may be a progressive glenoid wear (GW) or loosening of the HHR. We therefore wanted to investigate the migration pattern (MP) of the HHR and also GW by using Radio Stereometric Analysis (RSA). Patients and methods21 patients (21 shoulders) with OA and a mean age of 64 years were enrolled in the study. They all received the Copeland humeral resurfacing head and were followed for 2 years with RSA. We evaluated the clinical outcome at 2 years with Western Ontario Osteoarthritis of the Shoulder (WOOS), EuroQol 5 dimension 3L (EQ-5D) and Constant Shoulder Score (CSS). In addition, we assessed data on WOOS and revisions until 5 years follow-up by using the local clinic data within the Swedish Shoulder Arthroplasty Register. ResultsAfter an initial migration at two months the implants were stable in relation to the humerus with no statistically significant difference between the 2 months and the 2 years value (p=0.23). The GW continued to increase during the study period with an initial migration of mean 2.3 mm and at 2 years 3.5 mm with a statistically difference between the 6 months and 2 years value (p=0.046). The WOOS, EQ-5D and CSS were all improved at 2 years compared to the preoperative values. We found a weak correlation between GW at 2 years and the WOOS score at 2 and 5 years, but these did not reach statistical significance. There were 4 revisions within 5 years after the primary operation, all due to pain. ConclusionThe marker-free RSA can be used in clinical studies for assessing migration in HHR implants and was also for the first time used to measure GW. The Copeland HHR seems to obtain a secure fixation in the humerus but shows continuous GW up to two years.

“Something Miraculous about Them”: ‘Indian Doctors’ and quacks in White Australia, 1880-1930

Delving into the historical narrative of medicine in colonial India and Australia, this article sheds light on a neglected aspect: the role of ‘Indian doctors,’ encompassing oculists and hakims, practitioners of indigenous Indian medicine, within the Australian landscape. Often marginalized in discussions of migration patterns and colonial medical history, these ‘Indian doctors’ possess a rich history intricately interwoven with the complex networks of the British Empire. Drawing upon the insights of scholars who have highlighted the mobility of ‘Indian doctors’ in Britain and Australia, this article underscores their significant presence and impact during the period spanning from 1880 to 1930. Through an analysis of contemporary Australian newspaper reports, the article unveils the popular representations of these practitioners and explores their influence across both regional outposts and urban centres within the confines of White Australia. By bringing the stories of these oft-forgotten healers to the forefront, this article aims to enrich our understanding of colonial medical dynamics and transnational networks.

Rare and highly destructive wildfires drive human migration in the U.S.

The scale of wildfire impacts to the built environment is growing and will likely continue under rising average global temperatures. We investigate whether and at what destruction threshold wildfires have influenced human mobility patterns by examining the migration effects of the most destructive wildfires in the contiguous U.S. between 1999 and 2020. We find that only the most extreme wildfires (258+ structures destroyed) influenced migration patterns. In contrast, the majority of wildfires examined were less destructive and did not cause significant changes to out- or in-migration. These findings suggest that, for the past two decades, the influence of wildfire on population mobility was rare and operated primarily through destruction of the built environment.

Improving spatial exposure data for everyone - lifecourse social context and ascertaining residential history.

Measuring age-specific, contextual exposures is crucial for lifecourse epidemiology research. Longitudinal residential data offers a "golden ticket" to cumulative exposure metrics and can enhance our understanding of health disparities. Residential history can be linked to myriad spatiotemporal databases to characterize environmental, socioeconomic, and policy contexts that a person experienced throughout life. However, obtaining accurate residential history is challenging in the United States due to the limitations of administrative registries and self-reports. Xu et al. (Am J Epidemiol. 2024; 193(2):348-359) detail an approach to linking residential history sourced from LexisNexis ® Accurint ® to a Wisconsin-based research cohort, offering insights into challenges with residential history collection. Researchers must analyze the magnitude of selection and misclassification biases inherent to ascertaining residential history from cohort data. A lifecourse framework can provide insights into why the frequency and distance of moves is patterned by age, birth cohort, racial/ethnic identity, socioeconomic status, and urbanicity. Historic and contemporary migration patterns of marginalized people seeking economic and political opportunities must guide interpretations of residential history data. We outline methodologic priorities for use of residential history in health disparities research, including contextualizing residential history data with determinants of residential moves, triangulating spatial exposure assessment methods, and transparently quantifying measurement error.

Aberrant migration features in primary skin fibroblasts of Huntington's disease patients hold potential for unraveling disease progression using an image based machine learning tool

Huntington's disease (HD) is a complex neurodegenerative disorder with considerable heterogeneity in clinical manifestations. While CAG repeat length is a known predictor of disease severity, this heterogeneity suggests the involvement of additional genetic and environmental factors. Previously we revealed that HD primary fibroblasts exhibit unique features, including distinct nuclear morphology and perturbed actin cap, resembling characteristics seen in Hutchinson-Gilford Progeria Syndrome (HGPS). This study establishes a link between actin cap deficiency and cell motility in HD, which correlates with the HD patient disease severity. Here, we examined single-cell motility imaging features in HD primary fibroblasts to explore in depth the relationship between cell migration patterns and their respective HD patients' clinical severity status (premanifest, mild and severe). The single-cell analysis revealed a decline in overall cell motility in correlation with HD severity, being most prominent in severe HD subgroup and HGPS. Moreover, we identified seven distinct spatial clusters of cell migration in all groups, which their proportion varies within each group becoming a significant HD severity classifier between HD subgroups. Next, we investigated the relationship between Lamin B1 expression, serving as nuclear envelope morphology marker, and cell motility finding that changes in Lamin B1 levels are associated with specific motility patterns within HD subgroups. Based on these data we present an accurate machine learning classifier offering comprehensive exploration of cellular migration patterns and disease severity markers for future accurate drug evaluation opening new opportunities for personalized treatment approaches in this challenging disorder.

Introduction to the special issue on the consequences of immigration policies on children, youth, and families who experience migration-related trauma.

We are excited to introduce this special issue on the consequences of immigration policies on children, youth, and families who experience migration-related trauma. International migration has increased over the last 5 decades. Recent estimates suggest that 281 million people live in a country other than the one in which they were born (McAuliffe & Triandafyllidou, 2021). These migratory patterns are complex and present both challenges and opportunities for trauma psychologists and professionals from diverse disciplines who approach their work with immigrants from a trauma-informed perspective. In this 21st century, a variety of stressors and crises continue to propel the movement of children, youth, and families across the globe. Trauma often pervades the experiences that cause people to leave their homes. They may need to escape oppressive political systems; criminal gangs, war, or disasters; or simply to survive. Migration itself can lead to exposure to additional traumatic events, such as physical and sexual violence, kidnapping, and trafficking. Finally, upon arrival in a host country, individuals may experience further stressors as they struggle to navigate immigration systems with discriminatory processes and inadequate resources. In this special issue, 14 articles illustrate various ways by which migration-related traumatic experiences can inform assessment and treatment, public health policy, and human rights advocacy. Focusing primarily on children and families, unaccompanied youth, and adult migrants from Latin America and other regions, the authors explore premigration, migration itself, and postmigration issues that arise when individuals migrate to survive. The articles highlight how the resiliency and strength of individuals and families can be called upon to empower them in their journey toward healing and the critical need for cross-disciplinary treatment and advocacy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Seasonal migration patterns of Siberian Rubythroat (Calliope calliope) facing the Qinghai–Tibet Plateau

BackgroundSmall songbirds respond and adapt to various geographical barriers during their annual migration. Global flyways reveal the diverse migration strategies in response to different geographical barriers, among which are high-elevation plateaus. However, few studies have been focused on the largest and highest plateau in the world, the Qinghai–Tibet Plateau (QTP) which poses a significant barrier to migratory passerines. The present study explored the annual migration routes and strategies of a population of Siberian Rubythroats (Calliope calliope) that breed on the north-eastern edge of the QTP.MethodsOver the period from 2021 to 2023, we applied light-level geolocators (13 deployed, seven recollected), archival GPS tags (45 deployed, 17 recollected), and CAnMove multi-sensor loggers (with barometer, accelerometer, thermometer, and light sensor, 20 deployed, six recollected) to adult males from the breeding population of Siberian Rubythroat on the QTP. Here we describe the migratory routes and phenology extracted or inferred from the GPS and multi-sensor logger data, and used a combination of accelerometric and barometric data to describe the elevational migration pattern, flight altitude, and flight duration. All light-level geolocators failed to collect suitable data.ResultsBoth GPS locations and positions derived from pressure-based inference revealed that during autumn, the migration route detoured from the bee-line between breeding and wintering grounds, leading to a gradual elevational decrease. The spring route was more direct, with more flights over mountainous areas in western China. This different migration route during spring probably reflects a strategy for faster migration, which corresponds with more frequent long nocturnal migration flights and shorter stopovers during spring migration than in autumn. The average flight altitude (1856 ± 781 m above sea level) was correlated with ground elevation but did not differ between the seasons.ConclusionsOur finding indicates strong, season-dependent impact of the Qinghai–Tibet Plateau on shaping passerine migration strategies. We hereby call for more attention to the unexplored central-China flyway to extend our knowledge on the environment-migration interaction among small passerines.

Parables for planetary crisis: storytelling and multispecies migration in Amitav Ghosh’s Gun Island

Throughout his oeuvre, Amitav Ghosh deals with storytelling and migration. Exploring legacies of empire and entanglements between the human and non-human world, his writing is driven by an ethical imperative to excavate “forgotten” stories, and, especially in his later texts, to find new forms of storytelling suited to capture pasts, presents, and futures shaped by a growing sense of planetary crisis. Gun Island (2019), a generic mix of personal quest narrative, thriller, romance, and folk tale, depicts a world disrupted by different forms of multispecies migration. Linking the Indian subcontinent, the US, and Europe, it chronicles voluntary and forced journeys of humans and animals between the Global North and South, intertwining refugee and climate crises in the Mediterranean and Bangladesh with the morally charged legend of the gun merchant, a seventeenth-century world traveller. The text brings current and historical links between migration and climate change, which are comparatively rarely treated in literary fiction, into sharp focus. As this essay argues, it highlights specifically the need to broaden the notion of migration literature and its subgenres to include both human and animal migration and the impact of globalization and current realities of climate change. Exploring genre and poetics in Gun Island, this essay reads the novel against the broader aesthetic and cultural-historical arguments made in Ghosh’s The Great Derangement (2016) and The Nutmeg’s Curse (2021). To explore Ghosh’s poetics, which fuse everyday realism with the uncanny, the improbable, and the mythical, this essay also draws on Thom van Dooren and Deborah Bird Rose’s notions of “ethography”. It argues that Gun Island, as a multispecies climate migration novel, responds to the author’s call for a rediscovery of storytelling beyond Western-style realism or SF, as a means to capture human and non-human subjectivities and to undo demarcations between rationality and spirituality.

Migration and accumulation patterns of plastic waste in the environment: A comprehensive simulation study

Plastic waste is commonly littered in the environment due to insufficient waste management practices. Mismanaged plastic waste may migrate and accumulate in terrestrial and aquatic environments. Plastic waste in the terrestrial environment is our topic of interest, as it can significantly contribute to the broader issue of plastic waste pollutants. Wind and surface runoff are the main factors affecting plastic movement in the terrestrial environment. On the other hand, land surfaces, as the resisting factors, have a role in facilitating the unique movement patterns. Our objectives are to simulate the motion rate and pattern of plastic movement by exposing five varieties of plastics to these driving and resisting variables. As foundational data, this study can be utilized to ascertain the probability of migration and accumulation in the terrestrial environment. Each plastic travels differently across different ground surfaces at various wind speed thresholds. For example, a plastic bag can be moved at 0.8 m/s on paved and bare terrain, while it requires 1.6 m/s to move a plastic bag on cutting grass. A plastic by surface runoff may already be in motion when driven at a 1 L/s rate. However, wind power will be more frequently encountered in the environment than runoff, which only occurs on rainy days. The data also shows varied patterns across various ground surfaces, i.e., how plastic waste is retained in vegetated regions, travels with soil particles in bare terrain, and is easily transported on paved terrain.

Safety assessment of silicone molds for food use: A comprehensive analysis of migration patterns and volatile compound release in European markets

Silicones can contain oligomers known as siloxanes, which are either by-products of the polymerization process or arise from chemical reactions during processing. They may also have both intentionally and non-intentionally added substances, making it crucial to verify that silicone molds are safe and appropriate for food use. In this study 44 silicone molds available in the market from different European countries were studied. Triple sequential migration assays at 100 ºC for 8 h each using food simulants (3 % acetic acid, 20 % ethanol, and 50 % ethanol) were conducted. Some samples were also tested 4 h at 100 ºC. Global migration assessments were only conducted on turbid samples, while qualitative and quantitative analyses of volatile compounds were performed using solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) in total immersion mode. During the screening analysis of samples of 50 % ethanol at 100 ºC for 8 h a total of 112 different volatile compounds were tentatively identified by MS spectra and quantitatively estimated (LODs = 0.00005–0.014 mg/kg). However, there was no observable migration in the case of 3 % acetic acid and 20 % ethanol. All samples comply with the legislation (Royal Decree 847/2011) in the case of siloxanes. Some samples exceeded specific migration limits for volatile compounds other than siloxanes after third migration in 50 % EtOH at 100 ºC for 8 h.

Fleeing a failing state: Self-selection, earnings, and migration costs

Three-quarters of the global migrant population have fled fragile contexts, with 64 percent hosted by similarly vulnerable countries. These contexts account for about 75 percent of those living in extreme poverty. Despite the scale of this phenomenon, the extent to which the self-selection of South–South migrants differs from those migrating to more developed countries remains poorly understood. In this paper, I investigate the self-selection of Venezuelan migrants during the 2015–2021 crisis, which led to greater migration to less developed countries such as Colombia and Peru, compared to more developed ones like the United States and Chile. Using individual-level data representative of the Venezuelan population and similar data on Venezuelan migrants in these key destination countries, the study finds that migrants are generally positively selected in terms of education compared to those who remain in Venezuela, with migrants to developed countries being positively sorted with respect to those to developing countries. However, comparing the cumulative distribution functions of pre-migration predicted earnings reveals that migrants to developing countries are negatively selected relative to stayers, while migrants to developed countries are positively selected. This highlights the significant role of unobserved abilities in shaping South–South migration patterns. Furthermore, a discrete choice model shows that women and college graduates face lower migration costs, independent of expected earnings at the destination. Factors such as the distance to the destination country and pre-crisis networks also play a crucial role in shaping migration decisions.

Counterurbanization in China? A case study of counties in Huang-Huai-Hai area from the perspective of urban-rural relations

For decades, China's urbanization has primarily involved trans-regional migration from inland areas to major city regions along the coast or within the interior. As urban-rural disparities diminish, China has transitioned to intra-regional urbanization. However, there remains a gap in understanding the effects of this transition of urban-rural relations within China. This study focuses on counties as the fundamental research unit, examining net migration of the Huang-Huai-Hai Area. The spatial differentiation and its influencing factors were analyzed using ArcGIS and linear regression techniques. The results indicated a shift in the net migration trend of counties' populations in the Huang-Huai-Hai Area around 2010. The phenomenon of “counterurbanization” after 2010 changed the underlying rationale for population net migration. Counties' net migration was affected by both their relationship with cities and internal county factors. The close connection with cities promoted population growth in the counties. In-situ urbanization was vital for county development. The industrial structural adjustments were pivotal in population retention. The healthcare and education resources affected the migration patterns. The “counterurbanization” in this area could create new urban-rural dynamics. The revitalization of county populations meant significant implications for rural revitalization. This study, which is one of the first studies ever of the phenomenon of counterurbanization in a developing country, can provide insights for the development of integrated urban-rural areas and rural revitalization efforts.

Broad-scale seasonal climate tracking is a consequence, not a driver, of avian migratory connectivity.

Tracking climatic conditions throughout the year is often assumed to be an adaptive behaviour underlying seasonal migration patterns in animal populations. We investigate this hypothesis using genetic markers data to map migratory connectivity for 27 genetically distinct bird populations from 7 species. We found that the variation in seasonal climate tracking across our suite of populations at a continental scale is more likely a consequence, rather than a direct driver, of migratory connectivity, which is primarily shaped by energy efficiency-i.e., optimizing the balance between accessing available resources and movement costs. However, our results also suggest that regional-scale seasonal precipitation tracking affects population migration destinations, thus revealing a potential scale dependency of ecological processes driving migration. Our results have implications for the conservation of these migratory species under climate change, as populations tracking climate seasonally are potentially at higher risk if they adapt to a narrow range of climatic conditions.

Establishing species boundaries in Bornean geckos.

Species delimitation using mitochondrial DNA (mtDNA) remains an important and accessible approach for discovering and delimiting species. However, delimiting species with a single locus (e.g. DNA barcoding) is biased towards overestimating species diversity. The highly diverse gecko genus Cyrtodactylus is one such group where delimitation using mtDNA remains the paradigm. In this study, we use genomic data to test putative species boundaries established using mtDNA within three recognized species of Cyrtodactylus on the island of Borneo. We predict that multi-locus genomic data will estimate fewer species than mtDNA, which could have important ramifications for the species diversity within the genus. We aim to (i) investigate the correspondence between species delimitations using mtDNA and genomic data, (ii) infer species trees for each target species, and (iii) quantify gene flow and identify migration patterns to assess population connectivity. We find that species diversity is overestimated and that species boundaries differ between mtDNA and nuclear data. This underscores the value of using genomic data to reassess mtDNA-based species delimitations for taxa lacking clear species boundaries. We expect the number of recognized species within Cyrtodactylus to continue increasing, but, when possible, genomic data should be included to inform more accurate species boundaries.

Migration across the urban hierarchy: Has China’s urbanisation transitioned from the primate city stage to the secondary city stage?

The population density in megacities in China gives rise to challenges, such as traffic congestion and soaring housing prices. A trend of leaving primate cities can be observed as well as a population increase in secondary cities. These trends might point to an urbanisation transition from the primate city stage to the secondary city stage. Research is needed to determine at which stage of urbanisation China currently resides, and who are migrating across the different levels of cities in this stage. In order to answer these questions, the current study combines the theory of differential urbanisation and migrant selectivity, and analyses city-level migration patterns and demographic characteristics of migrants across the urban hierarchy. The findings indicate that China is currently in the intermediate primate city stage, where the upward migration across the urban hierarchy is driven by younger adults with higher education and income, and a lower likelihood of marriage or parenthood. Building upon global evidence, this research further extends the theory of differential urbanisation by incorporating migrant selectivity into the interpretation of urbanisation stages. It reveals that educated migrants tend to concentrate and move up the urban hierarchy in the primate city stage but might deconcentrate during the secondary and small city stages. This study offers practical insights for policymakers at the national and city levels to develop population growth plans, adjust targeted migration policies and respond to future urbanisation processes.