Hasil untuk "Colonies and colonization. Emigration and immigration. International migration"

Yolanda López García, Maria Catarina Chitolina Zanini, Asmara González Rojas

Resumen: Este artículo aborda temas actuales dentro del campo de los estudios migratorios contemporáneos, busca reflexionar sobre el cuidado, las reinvenciones y las nuevas formas de investigación, así como compartir los resultados de estas con y entre los interlocutores. Al cuestionar el rol tanto del investigador como del investigado en contextos de investigación, buscamos ampliar la comprensión de los límites de las metodologías y los análisis que se centran en gran medida en constructos epistemológicos eurocentrados. Enfatizamos cómo las nuevas tecnologías y los contextos neoliberales exigen una mirada más atenta y vigilante al conocimiento que producimos y cómo se produce. Presentar los escenarios en los que se desenvuelven las migraciones, tanto a los individuos como a sus colectivos, requiere una escucha atenta y la observación de sus especificidades, así como datos cuantitativos que nos permitan obtener una visión panorámica de ciertos fenómenos y de sus lógicas.

Erika Gubrium, Laia Colomer

The study investigates how adult migrants to Norway develop a sense of belonging through both attachment and mobility. Building on transnational and mobilities perspectives, it emphasizes embodied affect—the sensory and emotional experiences arising from everyday routines, movements, and interactions with place. Drawing on a three-stage, mixed-method design (life-history interviews, mapping, and walking interviews) and through narrative inquiry focused on two ‘telling cases’, the analysis shows that belonging evolves in the interplay of physical environments, personal and family relationships, and one’s broader social and cultural context. Rather than viewing belonging as solely rooted in fixed locations, the findings highlight how the research participants negotiate a sense of belonging ‘on the move’, across multiple sites. These negotiations entail recalling memories of origin, managing daily routines in Norway, and anticipating future transnational ties. By foregrounding the embodied and affective dimensions of belonging, the paper contributes to a nuanced understanding of migrants’ experiences and underscores how movement and place-based attachment coexist and continually reshape one another.

Mateusz Ratman, Jimmy Gonzalez Nuñez, Daniel A. Beller

Mechanical interactions among cells in a growing microbial colony can significantly influence the colony's spatial genetic structure and, thus, evolutionary outcomes such as the fates of rare mutations. Here, we computationally investigate how this spatial genetic structure changes as a result of heritable phenotypic variations in cell shape. By modeling rod-like bacterial cells as lengthening and dividing circo-rectangles in a 2D Brownian dynamics framework, we simulate the growth of a colony containing two populations with different aspect ratios. Compared to monodisperse colonies, such bidisperse colonies exhibit diminished intermixing between sub-populations when the less elongated cells are too short to nematically order, instead forming large clusters. We find that the cells with longer aspect ratio gradually segregate to the colony periphery. We present evidence that this demixing is related to nematic order in the bulk and to active nematic mixing dynamics near the periphery. These findings are qualitatively robust across different growth rate protocols and initial conditions. Because the periphery is often an advantageous position when nutrients are limited, our results suggest a possible evolutionary selective pressure of mechanical origin that favors large cell aspect ratio.

Aleksandar Mijatović, Benjamin Povar, Gerónimo Uribe Bravo

We establish the joint scaling limit of a critical Bienaymé-Galton-Watson process with immigration (BGWI) and its (counting) local time at zero to the corresponding self-similar continuous-state branching process with immigration (CBI) and its (Markovian) local time at zero for balanced offspring and immigration laws in stable domains of attraction. Using a general framework for invariance principles of local times~\cite{MR4463082}, the problem reduces to the analysis of the structure of excursions from zero and positive levels, together with the weak convergence of the hitting times of points of the BGWI to those of the CBI. A key step in the proof of our main limit theorem is a novel Yaglom limit for the law at time $t$ of an excursion with lifetime exceeding $t$ of a scaled infinite-variance critical BGWI. Our main result implies a joint septuple scaling limit of BGWI $Z_1$, its local time at $0$, the random walks $X_1$ and $Y_1$ associated to the reproduction and immigration mechanisms, respectively, the counting local time at $0$ of $X_1$, an additive functional of $Z_1$ and $X_1$ evaluated at this functional. In the septuple limit, four different scaling sequences are identified and given explicitly in terms of the offspring generating function (modulo asymptotic inversion), the local extinction probabilities of the BGWI and the tails of return times to zero of $X_1$.

Jonathan Bauermann, David R. Nelson

We study the genetic interfaces between two species of an expanding colony that consists of individual microorganisms that reproduce and undergo diffusion, both at the frontier and in the interior. Within the bulk of the colony, the genetic interface is controlled in a simple way via interspecies interactions. However, at the frontier of the colony, the genetic interface width saturates at finite values for long times, both for neutral strains and interspecies interactions such as antagonism. This finite width arises from geometric effects: genetic interfaces drift toward local minima at an undulating colony frontier, where a focusing mechanism induced by curvature impedes diffusive mixing. Numerical simulations support a logarithmic dependence of the genetic interface width on the strength of the number fluctuations.

William Incacutipa, Laymir Apaza, Clever Mamani et al.

This study examines the low population presence in the Community Campesina de Antacahua, aiming to identify migration drivers and assess their correlation with rural-to-urban migration trends. Employing a mixed approach, including surveys, normative, and bibliographic analysis, the research reveals that emigration is propelled by factors like dissatisfaction with inadequate services (34.4%), economic support deficiency (23.4%), low crop productivity (15.6%), study-related reasons (18.8%), and land scarcity (7.8%). Emigrants, comprising teenagers (12.5%), young adults (17.2%, 43.7%), and adults (26.6%), prefer destinations like Juliaca (40.0%), Puno (23.0%), Ananea and Cojata mines (25.0%), and other locations (12.0%). Literature analysis highlights insufficient government policies, suggesting solutions like promoting basic services through land allocation and enhancing economic opportunities by integrating new members into the Communal Directive.

Jiayan Guo, Wenming Hong

We focus on the partial sum $S_{n}=X_{1}+\cdots+X_{n}$ of the critical branching process with immigration $\{X_{n}\}$, when the offspring $ξ$ is regularly varying with index $ν+1$ and the immigration $η$ is regularly varying with index $δ$ $(0\leq ν<δ<1)$. The precise large deviation probabilities for $S_{n}$ are specified, that is, for some appropriate sequences $\{x_{n}\}$ and $\{y_{n}\}$, uniformly for $x_{n}\leq x\leq y_{n}$, $P(S_{n}>x)\sim nx^{-δ/(1+ν)}L(x)$, where $L(x)$ is a slowly varying function. Different from that of the subcritical case, here the upper bound $y_n$ is needed. Essentially, this is because the tail probability of the stationary distribution is determined by the offspring or the immigration in the subcritical case. But it is determined by both when the process is critical.

Francisco Rodríguez

This paper examines the potential impact of different US economic sanctions policies on Venezuelan migration flows. I consider three possible departures from the current status quo in which selected oil companies are permitted to conduct transactions with Venezuela's state-owned oil sector: a return to maximum pressure, characterized by intensive use of secondary sanctions, a more limited tightening that would revoke only the current Chevron license, and a complete lifting of economic sanctions. I find that sanctions significantly influence migration patterns by disrupting oil revenues, which fund imports critical to productivity in the non-oil sector. Reimposing maximum pressure sanctions would lead to an estimated one million additional Venezuelans emigrating over the next five years compared to a baseline scenario of no economic sanctions. If the US aims to address the Venezuelan migrant crisis effectively, a policy of engagement and lifting economic sanctions appears more likely to stabilize migration flows than a return to maximum pressure strategies.

Xausa, Chiara

This article proposes a reading of How Beautiful We We Were, a timely novel about intergenerational justice and politics published in 2021 by Cameroonian-American author Imbolo Mbue. The first part of the article introduces the field of postcolonial ecocriticism and examines the historical and contemporary impacts of colonialism on the environment as represented in the novel. My reading then foregrounds the voices of resistance and activism of How Beautiful We Were’s young protagonists and their coming-of-age as postcolonial eco-citizens, and finally moves to highlight the urgency for environmental justice and decolonization in the face of ongoing global environmental challenges.

Jakub A. Kochanowski, Bobby Carroll, Merrill E. Asp et al.

Bacteria build multicellular communities termed biofilms, which are often encased in a self-secreted extracellular matrix that gives the community mechanical strength and protection against harsh chemicals. How bacteria assemble distinct multicellular structures in response to different environmental conditions remains incompletely understood. Here, we investigated the connection between bacteria colony mechanics and the colony growth substrate by measuring the oscillatory shear and compressive rheology of bacteria colonies grown on agar substrates. We found that bacteria colonies modify their own mechanical properties in response to shear and uniaxial compression with the increasing agar concentration of their growth substrate. These findings highlight that mechanical interactions between bacteria and their microenvironment are an important element in bacteria colony development, which can aid in developing strategies to disrupt or reduce biofilm growth.

Nane Aleksanyan

This article comparatively analyzes the manifestations and various factors of political populism in the European post-transitional periphery. The main difficulty in mapping political populism in the European post-transitional periphery and defining populist parties most accurately is that, unlike most political forces in developed democracies, such parties do not belong to traditional parties. Moreover, their ideology combines the positions of both right and left parties, which makes it extremely difficult to place them on the classical right-left scale of the party spectrum. The political agenda of the populist parties of the European post-transition peripheral countries has a different content, but it usually comes down to updating issues that are hushed up by the political establishment: protecting national and cultural identity, taking tough measures aimed at combating corruption and crime, protecting traditional family values, and even harsh criticism of the Council of Europe, the OSCE and the EU and their institutions. A distinctive feature of the populist forces was also that in their majority they called for the protection of the rights and interests of ordinary people and the wider use of the instruments of direct democracy, and thus directly opposed one of the fundamental principles of liberal democracy, taking into account the opinion of the minority. The article analyzes the emergence of a populist environment, where the responsibility, trust and dignity of politicians are distorted, which in turn leads to a crisis of understanding and civiliarchic culture. The influence of populist parties has grown and most European post-transitional peripheral countries have at least one successful populist party, and populists are among the most influential parties. It is noteworthy that civil society organizations have identified the activities of populist leaders and their parties as the main threat facing the Eastern Partnership countries. Using populist technologies, mainly in the context of an election campaign, leaders and their political groups seek to manipulate public opinion and change the alignment of political parties in the European post-transitional periphery.

Mulugeta Dinbabo

Rebekah Hall, Daniel A. Charlebois

Yeasts exist in communities that expand over space and time to form complex structures and patterns. We developed a computational lattice-based framework to perform spatial-temporal simulations of budding yeast colonies exposed to different nutrient and magnetic field conditions. The budding patterns of haploid and diploid yeast cells were incorporated into the framework, as well as the filamentous growth that occurs in yeast colonies under nutrient limiting conditions. Simulation of the lattice-based model predicted that magnetic fields decrease colony growth rate, density, and roundness. Magnetic field simulations further predicted that colony elongation and boundary fluctuations increase in a nutrient- and ploidy-dependent manner. These in-silico predictions are an important step towards understanding the effects of the physico-chemical environment on microbial colonies and for informing bioelectromagnetic experiments on yeast colony biofilms and fungal pathogens.

Jesús Rivera-Navarro, Elisa Brey, Manuel Franco

The analysis of urban health transformations must include the study of how neighbourhoods are influenced by demographic changes such as immigration. The objective of this study was to analyse how the relationship between native and immigrant residents in neighbourhoods with different socio-economic levels influenced the use of urban health assets, such as public spaces and food stores. Three Madrid neighbourhoods of different socio-economic levels were selected and studied by conducting 37 semi-structured interviews and 29 focus groups. Data analysis was based on qualitative sequential discourse.The main finding was that the presence of immigrants in Madrid neighbourhoods, especially with low and medium socio-economic levels, was perceived negatively, affecting the use of public spaces and food stores. This negative perception unfolded in three dimensions: (1) difficulties for natives and immigrants to live together; (2) limitations on using public spaces caused by a feeling of insecurity; (3) criticism of immigrant food stores, especially Chinese-run food stores. Our findings showed a worrisome lack of social contact between immigrants and native residents, which affected the use of urban health assets, such as public spaces and food stores.

Masoud Ghods, Zahra Rostami

In the article, we review and critique the Corollary and Theorem of Wiener index of a fuzzy graph and application to illegal immigration networks, and in addition to providing examples of violations.

Fernando Cesar Sossai, Ilanil Coelho, Samira Peruchi Moretto

Marlene de Fáveri, Fernanda Arno

Martin Friesen, Peng Jin, Barbara Rüdiger

In this article we provide a sufficient condition for a continuous-state branching process with immigration (CBI process) to not hit its boundary, i.e. for non-extinction. Our result applies to arbitrary dimension $d \geq 1$ and is formulated in terms of an integrability condition for its immigration and branching mechanisms $F$ and $R$. The proof is based on a suitable comparison with one-dimensional CBI processes and an existing result for one-dimensional CBI processes. The same technique is also used to provide a sufficient condition for transience of multi-type CBI processes.

Martin Friesen

In this work we study the long-time behavior for subcritical measure-valued branching processes with immigration on the space of tempered measures. Under some reasonable assumptions on the spatial motion, the branching and immigration mechanisms, we prove the existence and uniqueness of an invariant measure for the corresponding Markov transition semigroup. Moreover, we show that it converges with exponential rate to the unique invariant measure in the Wasserstein distance as well as in a distance defined in terms of Laplace transforms. Finally, we consider an application of our results to super-Lévy processes as well as branching particle systems on the lattice with noncompact spins.

Samira Peruchi Moretto