Migration Process Research Articles

Ultrafast Imaging of Jahn-Teller Distortion and the Correlated Proton Migration in Photoionized Cyclopropane.

The Jahn-Teller (JT) distortion is one of the fundamental processes in molecules and condensed phase matters. For photoionized organic molecules with high symmetry, the JT effect leads to geometric instability in certain electron configurations and thus has a significant effect on the subsequent isomerization and proton migration processes. Utilizing the femtosecond pump-probe Coulomb explosion method, we probe the isomerization dynamics process of a monovalent cyclopropane cation (C3H6+) caused by proton migration and reveal the relationship between proton migration and JT distortion. We found that the C3H6+ cation evolves from the D3h symmetric equilateral triangle geometry either to the acute triangle via two elongated C-C bonds (JT1) or to the obtuse triangle via a single elongated C-C bond (JT2). The JT1 pathway does not involve proton migration, while the JT2 pathway drives proton migration and can be mapped into the indirect dissociation channel of Coulomb explosion. The time-resolved experiment indicates that the delay time between those two JT pathways can be as large as ∼600 fs. After the JT distortion, the cyclopropane cation undergoes a subsequent structural evolution, which brings a greater variety of dissociation channels.

The role of dispersal limitation in the forest biome shifts of Europe in the last 18,000 years

AbstractAimHow the ability of plants to move towards newly favourable habitats (dispersal limitation) impacts the change of biome distribution and transition under fast climate warming is still debated. Analysing vegetation change in the past may help to clarify the relative importance of underlying ecological processes such as climate, biotic interactions, and dispersal. In this study, we investigated how dispersal limitation affected the distribution of European forests in the last 18,000 years.LocationSouthern and Central Europe.TaxonSpermatophyta.MethodsUsing the LPJ‐GM 2.0 model (an extension of LPJ‐GUESS), we simulated European vegetation from the end of the Last Glacial Maximum (18.5 ka) to the current time (0 ka). Using biome reconstructions from pollen data as reference, we compared the performance of two dispersal modes: with no migration constraints or seed limitation (free dispersal mode), and with plant establishment depending on seed dynamics and dispersal (dispersal limitation mode).ResultsThe model run, including migration processes, was better at capturing the post‐glacial expansion of European temperate forests (and the longer persistence of boreal forests) than the setting assuming free dispersal, especially during periods of rapid warming. This suggests that a number of (temperate) tree taxa experienced delayed occupancy of climatically suitable habitats due to a limited dispersal capacity, i.e., post‐glacial migration lags.Main ConclusionsOur results show that including migration processes in model simulations allows for more realistic reconstructions of forest patterns under rapid climate change, with consequences for future projections of carbon sequestration and climate reconstructions with vegetation feedback, assisted migration and forest conservation.

ETHNOSTATISTICAL STUDIES OF MULTINATIONAL RUSSIA IN THE WORKS OF VIKTOR IVANOVICH KOZLOV (on the 100th Anniversary of the Scientist’s Birth)

The purpose of the article is to analyze the ethnographic monographs of Viktor Ivanovich Kozlov, one of the famous and outstanding researchers of multinational Russia. In 1975, V.I. Kozlov’s book “Nationalities of the USSR (Ethno-demographic review)” was published, the uniqueness of which is explained by the fact that it was the first empirical experience of ethnostatistical studying the country’s population. Later, in 1982, V.I. Kozlov’s book “Nationalities of the USSR: an Ethnogeographic Review” was published, which presents scientific material on the Mordvins in the context of the Volga region peoples. V.I. Kozlov analyzed and illustrated the main patterns of demographic development and the reasons for the change in the quantitative indicator of population. In the ethnogeographic review, Viktor Ivanovich singled out a semi-ethnic, semi-estates group of “Teptyars”, representing immigrants from the Volga region, formed from a mixture of mainly the Tatars and the Mordvins. He explained the introduction of the term “Mordovian dialect” in the 1897 census, which took into account the ethno-lingual and religious composition of the population. Viktor Ivanovich is also known for his contribution to the development of Russian cartography and preservation of ethnographic maps when developing the scientific research topic dedicated to the settlement of the Mordovian people. The settlement of the Erzya and the Moksha in the Volga region in 1926 is shown on an ethnographic map, which reflects the results of migrations of the Mordvins over the entire previous period. Materials and methods. With the help of the historical and ethnographic method, a comprehensive analysis of demographic processes, the history of forming the national composition of the population, the geography of settlement of various nationalities across the country, and the features of demographic development was carried out. Study results. The published works of V.I. Kozlov’s works reflect the history of forming the ethnic composition of the population, the geography of settlement of various nationalities on the territory of Russia, and the peculiarities of demographic development. In migration of the peoples of Russia, it is necessary to focus also on multinationality formation in the Republic of Mordovia, as one of the regions of the Volga Region in the Russian Federation. In the Republic of Mordovia, scientists are studying the migration processes of the Eastern Slavs, the peoples of Central Asia and Transcaucasia, ethnographic expeditions have been conducted, but in general this aspect has not been fully understood. Conclusions. Small-numbered peoples live in Mordovia, which have been studied in fragments and require additional research, including according to the All-Russian Census of 2020. Methodology of V.I. Kozlov provided significant assistance in collecting, analyzing and typologizing the formation of multinationality, including foreign population in the Republic of Mordovia.

Risk-based approach in external migration public management

The presence of risks emergence problem of socio-political conflict, threats to the preservation of Russian identity in the process of including foreign cultural groups of international migrants in Russian society is a consequence of public administration insufficient efficiency when implementing state migration and national policy. Applying the structural-functional method, the authors study public administration in the external migration sphere for compliance with its essential characteristics. The predominant focus of state management in the migration sphere on ensuring the human resources component of the Russian labor market, as well as on control over migration flows is combined with the state management model shortcomings in the sphere of migrants’ inclusion in the host community. External migration state management should be aimed at solving the socio-economic development problems in Russia and ensuring national security and at the same time should minimize potential risks of social and cultural nature. The authors propose a risk-oriented approach in the migration processes state management, based on a comprehensive consideration of tensions that arise both in the labor market of foreign workers and the foreigners’ inclusion in the Russian society. In order to implement the proposed method, it is advisable to define a single subject of state management, which will be able to exercise authority considering the migration process integrity.

Abstract 4128: Biofield therapy suppressed invasion and metastases of human pancreatic cancer

Abstract The NIH categorizes Biofield Therapy (BT) as therapeutic approaches within energy medicine that involve using the body's energy field (biofield) for therapeutic benefit. Although controversial, in some cases devices have been developed that mimic the electromagnetic fields (EMF) that are emitted from people when delivering BTs. We previously reported that BT significantly inhibited the growth of pancreatic cancer cells and liver metastasis in their relevant animal models mediated in part through modification of the cell cycle, reductions in cell voltage potentials, and down regulation of PI3K/Akt pathways. We expanded this research to examine the potential role of BT in anti-invasiveness in human pancreatic ductal adenocarcinoma (PDAC) cells and animal models. We found that PANC-1 cells treated with BT (15 min) displayed 55% less invading cells than that of untreated incubator control and sham control cells (P < 0.001). Similar results were observed in human PDAC L3.7 cells and mouse pancreatic cancer KPCY cells. These experiments were replicated 8 times for Panc-1 cells and 4 times for L3.7 cells. Additionally, migration capacity was tested using the transwell migration and scratch assays. Consistent with the result of cell invasion assays, BT treatment also led to significant reduction of migration of PANC-1 and L3.7 cells by 34% and 41%, respectively, compared to sham controls. Two additional therapists independently replicated the anti-invasiveness and anti-migratory effects of BT on these PDAC cells. This suggests the replicability of these findings across studies and therapists. In a repeated PANC-1 mouse orthotopic model, we found that only a third of BT treated mice had visible liver nodules whereas liver metastasis was observed in more than half of mice in the untreated colony control and sham control groups. Furthermore, BT treatment significantly reduced liver tumor burden by 73% compared to that of the sham control group (p < 0.05), which was similar to that observed in the previous study. Similar to the prior PANC-1 mouse model, in the current study BT treatment had only a moderate impact on the growth of primary pancreatic tumor. We assessed certain markers indicative of cell status as well as pathways associated with migration and invasion and these will be presented at the meeting. Our findings suggest that exposure to BT reduced cellular invasion and migration processes and profoundly reduced metastasis of pancreatic tumor in an animal model. This study is in part supported by Emerald Gate Charitable Trust. Citation Format: Peiying Yang, Sharmistha Chakraborty, Phuong Nguyen, Defeng Deng, Andrew Cusimano, Daoyan Wei, Lorenzo Cohen. Biofield therapy suppressed invasion and metastases of human pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4128.

Abstract 1648: RB represses cohesin-dependent loop formation and activates E2F-independent transcription

Abstract The retinoblastoma protein (RB) suppresses the activity of the E2F transcription factor family, controlling cellular proliferation. Recent studies, however, indicate that RB's role in chromatin organization, which is not yet fully understood, might be distinct from this E2F-dependent regulation. Employing chromosome conformation capture at a single nucleosome resolution, we identified RB as a cell cycle-regulated repressor of cohesin-dependent loop formation at topologically associating domain (TAD) boundaries. RB depletion increased the number and size of cohesin-dependent loops and strengthened topologically associating domains (TADs). This phenomenon was specific to the G1 phase and was not observed in the S phase, indicating that this novel RB function is regulated by the cell cycle. Mechanistically, RB showed extensive colocalization with cohesin in the human genome, and it impacted cohesin’s distribution on the chromatin. Active RB reduced cohesin from RB-bound TAD boundaries and decreased cohesin activity therein, as assessed by the increased K105/106 acetylation of the cohesin subunit SMC3. This led to reduced insulation in chromosome conformation capture assays. Importantly, by weakening the insulation activity of the adjacent insulators, RB non-canonically enhanced the expression of non-E2F target genes salient for cell adhesion and extracellular matrix organization. When RB was lost, cells showed a more rapid cellular detachment rate and an elevated migration rate, indicating that this novel RB function controls specific transcriptional programs rather than arbitrary genes to regulate the process of cell adhesion and migration. Overall, we conclude that RB has a central role in the interplay between cell cycle and chromatin organization, by repressing the cohesin-dependent loop formation at TAD boundaries. This RB function safeguards E2F-independent transcriptional programs driven by active enhancers and helps maintain cellular adhesion to the extracellular matrix. Citation Format: Hanjun Lee, Ioanna-Maria Gkotinakou, Badri Krishnan, Nicholas J. Dyson, Michael S. Lawrence, Ioannis Sanidas. RB represses cohesin-dependent loop formation and activates E2F-independent transcription [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1648.

Spatial-temporal distribution of visceral leishmaniasis in Rio de Janeiro, Brazil, 2001-2020: expansion and challenges.

Visceral leishmaniasis results from complex interactions among humans, dogs and environment. Brazil accounts for 97% of cases in the Americas. Twenty years (2001-2020) of the endemic disease in the state of Rio de Janeiro were studied. Incidence, lethality, sociodemographic and clinical characteristics were investigated, complemented with spatial methodologies (kernel and clusters). Ninety-seven human cases and 625 dogs were reported. Of the 92 cities, 22 were human endemic areas. The state had a low incidence level (0.6 per 100 000). Lethality was higher compared with the Brazilian average. More than 90% of infections occurred in urban areas. Most cases (66%) occurred in men. The predominant age groups were 0-4 y (28.7%) and 20-39 y (32.9%). Fever (89.5%), splenomegaly (83.2%) and hepatomegaly (76.8%) were the main clinical manifestations. Spatial analysis showed a displacement of the human endemic: in the first decade (2001-2010), cases were concentrated in the Metropolitan region, and in the second decade (2011-2020) in the Médio Paraíba region of the state. Most of the endemic area (56.4%) had canine infections without reported human cases. Disorderly urbanisation and precarious living conditions favour the transmission of the disease. Changes in the environment and migratory processes contribute to its expansion.

Soil Contamination by Heavy Metals and Radionuclides and Related Bioremediation Techniques: A Review

The migration of heavy metals and radionuclides is interrelated, and this study focusses on the interaction and complex influence of various toxicants. The rehabilitation of radioactively contaminated territories has a complex character and is based on scientifically supported measures to restore industrial, economic, and sociopsychological relations. We aim for the achievement of pre-emergency levels of hygienic norms of radioactive contamination of output products. This, in its sum, allows for further economic activity in these territories without restrictions on the basis of natural actions of autoremediation. Biosorption technologies based on bacterial biomass remain a promising direction for the remediation of soils contaminated with radionuclides and heavy metals that help immobilise and consolidate contaminants. A comprehensive understanding of the biosorption capacity of various preparations allows for the selection of more effective techniques for the elimination of contaminants, as well as the overcoming of differences between laboratory results and industrial use. Observation and monitoring make it possible to evaluate the migration process of heavy metals and radionuclides and identify regions with a disturbed balance of harmful substances. The promising direction of the soil application of phosphogypsum, a by-product of the chemical industry, in bioremediation processes is considered.

Deep-unrolling architecture for image-domain least-squares migration

Deep-image prior (DIP) is a novel approach to solving ill-posed inverse problems whose solution is parameterized with an untrained deep neural network and cascaded with the forward modeling operator. A key component to the success of such a method is represented by the choice of the network architecture, which must act as a natural prior to the inverse problem at hand and provide a strong inductive bias toward the desired solution. Inspired by the close link between neural networks and iterative algorithms in classical optimization, we apply an unrolled version of the gradient descent (GD) algorithm as our DIP network architecture, denoted as the deep-unrolling (DU) architecture. Each layer of the unrolled network is comprised of two parts: the first part corresponds to the GD step of the data-fidelity term, whereas the second part, formed by a six-layer convolutional neural network (CNN), plays the role of a regularizer in the associated objective function. The developed DU architecture is applied to the problem of image-domain least-squares migration (IDLSM) to invert migrated seismic images for their underlying reflectivity and is denoted as DU-IDLSM. As such, the DU architecture parameterizes the reflectivity, and the input of each layer of the unrolled network is the reflectivity at the previous layer. Similar to the classical DIP approach, the parameters of the DU architecture are optimized in an unsupervised fashion by minimizing the data misfit function itself. Through experiments with a part of the Sigsbee2A model and a marine field data set, we test the effectiveness of the DU-IDLSM approach and highlight two key benefits. First, the DU architecture can effectively regularize the inversion process, resulting in reflectivity estimates with fewer artifacts and higher image resolution than those produced by conventional IDLSM approaches. Second, we indicate that by including dropout layers in the CNN architecture, DU-IDLSM can produce a qualitative measure of the uncertainty associated with the least-squares migration process.

Research Advances in Neuroblast Migration in Traumatic Brain Injury.

Neuroblasts were first derived from the adult mammalian brains in the 1990s by Reynolds et al. Since then, persistent neurogenesis in the subgranular zone (SGZ) of the hippocampus and subventricular zone (SVZ) has gradually been recognized. To date, reviews on neuroblast migration have largely investigated glial cells and molecular signaling mechanisms, while the relationship between vasculature and cell migration remains a mystery. Thus, this paper underlines the partial biological features of neuroblast migration and unravels the significance and mechanisms of the vasculature in the process to further clarify theoretically the neural repair mechanism after brain injury. Neuroblast migration presents three modes according to the characteristics of cells that act as scaffolds during the migration process: gliophilic migration, neurophilic migration, and vasophilic migration. Many signaling molecules, including brain-derived neurotrophic factor (BDNF), stromal cell-derived factor 1 (SDF-1), vascular endothelial growth factor (VEGF), and angiopoietin-1 (Ang-1), affect vasophilic migration, synergistically regulating the migration of neuroblasts to target areas along blood vessels. However, the precise role of blood vessels in the migration of neuroblasts needs to be further explored. The in-depth study of neuroblast migration will most probably provide theoretical basis and breakthrough for the clinical treatment of brain injury diseases.

DI CƯ ĐÔ THỊ VÀ HIỆU ỨNG ĐẾN CÔNG NHÂN LAO ĐỘNG Ở THÀNH PHỐ HỒ CHÍ MINH HIỆN NAY

The article mentions the migration factor associated with the movement of labor in Ho Chi Minh City, specifically the number of workers by urban and rural areas by economic sector and enterprise sector. There have been both positive and negative impacts, especially on immigrant workers. Research methods of dialectical materialism, historical materialism along with the approach of historical science were used. In addition, data collection methods and data analysis methods combined with sociological approaches are also applied. The research results reconstruct the overall migration process in Ho Chi Minh City and its impacts. Simultaneously, the article offers a number of recommendations to improve policies for this group with the purpose of advising the government to promote migrant workers in the coming years

Early developmental changes in a rat model of malformations of cortical development: Abnormal neuronal migration and altered response to NMDA-induced excitotoxic injury

Malformations of cortical development (MCDs) are caused by abnormal neuronal migration processes during the fetal period and are a major cause of intractable epilepsy in infancy. However, the timing of hyperexcitability or epileptogenesis in MCDs remains unclear. To identify the early developmental changes in the brain of the MCD rat model, which exhibits increased seizure susceptibility during infancy (P12–15), we analyzed the pathological changes in the brains of MCD model rats during the neonatal period and tested NMDA-induced seizure susceptibility.Pregnant rats were injected with two doses of methylazoxymethanol acetate (MAM, 15 mg/kg, i.p.) to induce MCD, while controls were administered normal saline. The cortical development of the offspring was measured by performing magnetic resonance imaging (MRI) on postnatal days (P) 1, 5, and 8. At P8, some rats were sacrificed for immunofluorescence, Golgi staining, and Western analysis. In another set of rats, the number and latency to onset of spasms were monitored for 90 min after the NMDA (5 mg/kg i.p.) injection at P8.In MCD rats, in vivo MR imaging showed smaller brain volume and thinner cortex from day 1 after birth (p < 0.001). Golgi staining and immunofluorescence revealed abnormal neuronal migration, with a reduced number of neuronal cell populations and less dendritic arborization at P8. Furthermore, MCD rats exhibited a significant reduction in the expression of NMDA receptors and AMPAR4, along with an increase in AMPAR3 expression (p < 0.05). Although there was no difference in the latency to seizure onset between MCD rats and controls, the MCD rats survived significantly longer than the controls.These results provide insights into the early developmental changes in the cortex of a MCD rat model and suggest that delayed and abnormal neuronal development in the immature brain is associated with a blunted response to NMDA-induced excitotoxic injury. These developmental changes may be involved in the sudden onset of epilepsy in patients with MCD or prenatal brain injury.

A general micromechanics-based model for precipitate strengthening and fracture toughness in polycrystal high entropy alloys

High-entropy alloys (HEAs) usually exhibit exceptional mechanical properties attributed to one of important core effects for serious lattice strain to impede dislocation motion compared to the traditional alloys. However, their roles on the quantitative measurement for precipitate strengthening and fracture toughness are lack using the existing physical model. Here, we propose a mechanistic modelling to study effect of heterogeneous strain caused by lattice distortion on the precipitate strengthening and fracture toughness in the HEAs, and then verify this role using atomic simulation. The results indicate that the lattice distortion and precipitate synergistically impede the grain boundary migration, increasing the strength. In the dilute alloy with a low lattice distortion, the grain boundary migration process is less sensitive to the precipitate size. The stress field generated by the lattice distortion relieves the stress concentration at the crack tip under external force. This in turn alleviates the accumulation of dislocations and reduces the probability of crack extension. Furthermore, the heterogeneous strain caused by lattice distortion counteracts some of the applied stress and raises the critical stress for crack extension, which enhances the plasticity and the critical stress intensity factor. The developed unified model would be applicable to high entropy ceramics in similar scenario.

Tunable Neuromorphic Switching Dynamics via Porosity Control in Mesoporous Silica Diffusive Memristors.

In response to the growing need for efficient processing of temporal information, neuromorphic computing systems are placing increased emphasis on the switching dynamics of memristors. While the switching dynamics can be regulated by the properties of input signals, the ability of controlling it via electrolyte properties of a memristor is essential to further enrich the switching states and improve data processing capability. This study presents the synthesis of mesoporous silica (mSiO2) films using a sol-gel process, which enables the creation of films with controllable porosities. These films can serve as electrolyte layers in the diffusive memristors and lead to tunable neuromorphic switching dynamics. The mSiO2 memristors demonstrate short-term plasticity, which is essential for temporal signal processing. As porosity increases, discernible changes in operating currents, facilitation ratios, and relaxation times are observed. The underlying mechanism of such systematic control was investigated and attributed to the modulation of hydrogen-bonded networks within the porous structure of the silica layer, which significantly influences both anodic oxidation and ion migration processes during switching events. The result of this work presents mesoporous silica as a unique platform for precise control of neuromorphic switching dynamics in diffusive memristors.

Riboflavin protects against pancreatic cancer metastasis by targeting TGF-β receptor 1

The inhibition of transforming growth factor-β1 (TGF-β1) signaling by targeting TGF-β receptor 1 (TβR1) has been considered as an ideal approach for the prevention of pancreatic cancer metastasis. Utilizing a pharmacophore model for TβR1 inhibitors, candidate compounds with the potential TβR1 binding ability were screened from the U.S. Food and Drug Administration (FDA) database, and riboflavin (RF) with a highest fit value was chosen to investigate its binding ability to TβR1 and effect on TGF-β1 signaling in pancreatic cancer cells. Molecular docking and cellular thermal shift assay (CETSA) proved that RF at pharmacological concentrations could directly bind to TβR1. Further studies showed that pharmacological concentrations of RF in vitro could block TGF-β1 signaling, suppress the migration and invasion, and prevent epithelial-mesenchymal transition (EMT) process of pancreatic cancer cells in the absence or presence of TGF-β1 stimulation, indicating that RF presented anti-metastatic effect in pancreatic cancer cells. Knockdown of TβR1 could significantly attenuate the effects of RF on the migration and EMT process in pancreatic cancer cells, further confirming that the anti-metastatic effect of RF was achieved by blocking TGF-β1 signaling after binding to TβR1. Moreover, in a mouse model of pancreatic cancer metastasis, it was certified that RF administration could block lung and liver metastases, TGF-β1 signaling and EMT process of pancreatic cancer in vivo. In summary, our findings showed that RF could block TGF-β1 signaling by directly binding to TβR1, thereby suppressing the metastasis of pancreatic cancer cells by inhibiting EMT process both in vitro and in vivo.

Migration processes and their management in South Asian countries on the example of India, Bangladesh and Pakistan

South Asia is a subregion of the world characterized by high migration mobility of the population. The number of emigrants from this region is more than 43 million people, and the number of immigrants is almost 14 million people. Most of them occur in the country’s three largest subregions by population: India, Bangladesh and Pakistan. The purpose of the study is to study the management of migration processes in South Asia. For this purpose, the following tasks were solved: territorial analysis of the direction of migration processes in the largest states of South Asia; studying the features of the regulatory framework in the field of migration policy in the region; analysis of approaches and methods for managing migration processes in India, Bangladesh and Pakistan. The directions of migration processes have been studied through territorial analysis: in the context of emigration and immigration. The author’s maps were compiled based on current migration data. The regulatory framework related to the implementation of migration policies in India, Bangladesh and Pakistan is analyzed. The features of the approaches and methods that are used in each of the three countries in relation to the regulation of migration processes both within South Asia and beyond its borders are identified. The following territorial specificity of migration processes in South Asia can be noted: the subregion is more a donor of international migrants (more than 43 million people) than a recipient (almost 14 million people); emigration is growing most rapidly in India, while in Bangladesh and Pakistan it is more regulated by the state and used as a factor in socio-economic development; Immigration processes are completely different in India, Bangladesh and Pakistan. India is characterized by a concentration of international flows, especially from neighboring countries, while Bangladesh and Pakistan are becoming new homes for refugees from Myanmar and Afghanistan, respectively. Migration processes in the countries of South Asia are characterized by intensive and multidirectional nature. Larger numbers of emigrants come from other subregions of the world, while immigration processes affect nearby countries. If we talk about intraregional migration processes, then India is the country that receives the largest number of immigrants from neighboring South Asian countries. Migration policy is an important part of the dynamic development of any modern state; currently India, Bangladesh and Pakistan are making efforts to formalize and institutionalize this process.

Assessment of the migration processes on the example of Kazakhstan

Today's migration is a rather complex and controversial process. Having a number of advantages and positive results for the development of the receiving and sending countries, it also leads to negative consequences. The more a country's population is involved in migration processes, the more acutely its consequences manifest. The situation is also aggravated by the increasing economic and political crises, which negatively affect the ability of third countries to maintain internal stability. The issue does not exclude the Central Asian region in the context of the intensification of local armed conflicts in adjacent territories and current geopolitical aspects. The study purpose is to assess migration processes and their impact on the Republic of Kazakhstan as the one of the ‘host’ countries in Central Asia. A chronology of key economic events regarding strategic opportunities in the migration processes was carried out. Taking into account the current regional and global challenges, it has been established that the current trends in migration processes have a positive effect on the development of the labor market as an important component of the national economy, contributing to an increase in the welfare of the country. At the same time, the policy of Kazakhstan is also trying to pursue a pragmatic immigration policy to prevent the negative impact of immigrants on the local population.

Language as a Factor in Access to Education for School-Age Migrants

The article discusses access to education in view of the needs of students from migrant families. Linguistic problems related to migration processes in the countries of the European Union and beyond are highlighted. An emphasis is placed on the Bulgarian language training of students coming from foreign educational systems who have enrolled in Bulgarian schools. Opportunities to implement additional training in Bulgarian as a second language for students entering different secondary school grades are analyzed, with a view to the successful continuation of their education. The EU language policy to stimulate multilingualism, which is also discussed as a global trend, is focused on. Based on the experience in South Korea, opportunities for the development of multicultural education are presented.

Diasporas of Ethnic Minorities in the Towns of Tobolsk Governorate in the Late XIX - Early XX Century: Demographic and Social Features

The authors present a comparative description, some socio-demographic features and migration processes of the ethnic groups of the Tobolsk Governorate in order to assess the level of the formation of ethno-confessional communities and diasporas there, to determine strategies for their adaptation and/or integration with local urban society at the turn of the XX century. Special attention is paid to representatives of the Jewish, Polish and German populations. The sources of the study are both the published results of the 1897 First General Census of the Russian Empire for the Tobolsk Governorate and census forms. Using the comprehensive analysis of personal data, there was obtained a sample based on the criterion of native language (Polish, Jewish, German) which included 308 Germans, 1840 Poles and 1876 Jews. The authors come to the conclusion that the number of local natives, the registered population, the structure of their families, and the religious buildings indicate the presence of Jewish and Polish diasporas in Tobolsk, a Jewish community in Yalutorovsk, and a Polish community in Ishim. At the same time, it was established that the German population in the towns was sparse; the Jewish community was the most closed one; mixed marriages were more common in the Polish and German communities and they were actively replenished by immigrants from the Kingdom of Poland and Baltic provinces.

An analysis of migration processes in the Murmansk Oblast: Problems and strategic prospects of single-industry towns

Subject. This article examines the single-industry town as a factor determining the economic situation in the Far North of Russia. Objectives. The article aims to analyze migration processes in the Far North and assess the impact of migration processes on population changes. Methods. For the study, we used the methods of comparative and systems analyses. Results. The analysis of the changes in demographic indicators of the Murmansk Oblast shows a high level of resistance of the region to changes in the external environment. The trends in birth and death rates in the Murmansk Oblast generally corresponds to the trends in these indicators in the country as a whole. Conclusions. Initiatives to unlock the economic potential of the Murmansk Oblast should be linked to federal development strategies and programmes.