migration patterns
Recently Published Documents

AbstractThe repair of photosystem II is a key mechanism that keeps the light reactions of oxygenic photosynthesis functional. During this process, the PSII central subunit D1 is replaced with a newly synthesized copy while the neighbouring CP43 antenna with adjacent small subunits (CP43 module) is transiently detached. When the D2 protein is also damaged, it is degraded together with D1 leaving both the CP43 module and the second PSII antenna module CP47 unassembled. In the cyanobacterium Synechocystis sp. PCC 6803, the released CP43 and CP47 modules have been recently suggested to form a so-called no reaction centre complex (NRC). However, the data supporting the presence of NRC can also be interpreted as a co-migration of CP43 and CP47 modules during electrophoresis and ultracentrifugation without forming a mutual complex. To address the existence of NRC, we analysed Synechocystis PSII mutants accumulating one or both unassembled antenna modules as well as Synechocystis wild-type cells stressed with high light. The obtained results were not compatible with the existence of a stable NRC since each unassembled module was present as a separate protein complex with a mutually similar electrophoretic mobility regardless of the presence of the second module. The non-existence of NRC was further supported by isolation of the His-tagged CP43 and CP47 modules from strains lacking either D1 or D2 and their migration patterns on native gels.

The final destination country for refugees heading to Europe may be a changing one depending on various factors, such as the relocation program at the EU level, their ability to make decisions, geographic factors, finances, available routes, visa options, networks, chance, labor markets, etc., but for many of them their choices are limited. The purpose of this paper is to show how refugees select their destination countries, by looking at similarities across European countries. We aim to explain how country-specific factors may relate to the magnitude of migration flows, employing cluster and network analysis, and connecting meso- and macro-levels. The variables considered in our analysis fall under the four types of factors for host countries described by Van Hear, Bakewell, and Long (2012). Our analysis reveals that host countries in Europe can be grouped into four clusters: (i) Top Destination Economically Performing Countries; (ii) Emergent Destination Countries; (iii) Periphery and Less Economically Performing Countries; and (iv) Outlier Countries.

The aim is to explain the link between climate-related issues and violent patterns in Colombia after the 2016 peace agreements. The main premise is that the effects of an erratic climate has an indirect but relevant influence in the emergence of new forms of violence. In other words, the climatic change and environmental degradation act as a “stressor” in different forms of violence in this commodity-based economy recovering from more than 50 years of internal armed conflict. The qualitative approach is based on semi-structured interviews with government representatives and academics to track different perspectives. It is argued that key environmental and climate-related issues in new forms of conflict after the peace deal are linked to the fragmentary distribution and control of land, the ongoing forced migration patterns, and expansion of a new and more lucrative illicit economy.

Background: Mixed results for functional outcomes and long-term fixation have been reported for first metatarsophalangeal arthroplasty. This prospective study was designed to evaluate the migration of the BioPro metatarsophalangeal-1 (MTP-1) joint hemiprosthesis with Roentgen stereophotogrammetric analysis (RSA). Migration patterns of the prosthesis, prosthesis-induced erosion of the metatarsal bone, and clinical outcomes were evaluated sequentially to 5 years postoperation (PO). Methods: Eleven female patients received the BioPro-1 hemiprosthesis. Prosthesis translation and metatarsal erosion were measured with RSA at immediately PO, 6 weeks, and 3, 6, 12, 36, and 60 months postoperatively. Clinical assessment was done by patient questionnaires. Results: RSA data of 9 patients were available for analysis. Median (range) number of markers used in RSA analysis, condition number, and mean error of markers around the prosthesis were 4 (3-7), 320 (208-862), and 0.13 (0.02-0.28), respectively. Progressive subsidence was seen up to 3 years PO (mean 2.1 mm, SE 0.32). Progressive metatarsal erosion was found from 1 year PO (mean 0.49 mm, SE 0.15). Pain, function, and quality scores improved after surgery and did not deteriorate at later follow-up moments. Conclusion: Model-based RSA of the BioPro-1 prosthesis shows nonstabilizing medial and distal translation and metatarsal erosion. Despite the measured migration and erosion, clinical outcomes improved and remained similar up to 5 years postoperation.

Abstract Human mobility is very important in understanding complex social and economic systems. With massive empirical datasets from the China Household Finance Survey and the National Statistics in the UK, we construct a migration probability matrix, and analyze the heterogeneous migration patterns. We then develop a random walk model to dynamically simulate the population distribution. In the stationary state, the resulting population distribution is in good agreement with the real statistical data. For comparison, simulations with an optimized gravity model and other datasets such as the census data in China are also performed. Further, the model simulation is applied to predict the demographic trend with different education levels. Our method could be generally extended to other real communities and internet worlds.

Part 3: Beyond the Songs contains three chapters. “Culturally Responsive and Sustaining Pedagogies” presents summaries of these teaching approaches alongside strategies to responsibly integrate the repertoire into school curriculums. “Music in Central America” is a brief overview of the diverse and rich music genres of the region and how historic events introduced, shaped, and eradicated music traditions. Genres described include music in the classic Mayan period, folkloric dance, Spanish music, the marimba, Nueva Canción, Garifuna music, Miskitu music, and current traditions. “A Brief History of Central America” provides a historical context for the song collection. Beginning with the first civilizations and ending with current events, this chapter chronicles the political history of the region, including the involvement of the U.S. government in business affairs and civil wars. This overview allows the reader to develop an awareness of the effects of colonization, continued foreign involvement, current political situations, and a basic understanding of human migration patterns from Central America to North America.

The commercially important Norwegian spring spawning herring is characterized by its extensive annual migrations and, on a decadal timescale, large shifts in migration patterns. These changes are not well understood, but have previously been linked to temperature, food availability, and size and age composition of the stock. Acoustic and trawl data from the International Ecosystem Surveys in the Nordic Seas, carried out annually in May since 1996, were used to analyze the spatial distribution of herring in the period 1996–2020. The dataset was disaggregated into age classes, and information about where the different age classes feed in May was derived. The analysis of herring feeding patterns in May confirms that the youngest age classes are generally found close to the Norwegian shelf, whereas the older age classes display larger variations in where they are distributed. During the period 1996–1998, the oldest age classes were found in the central and western Norwegian Sea. During the period 1999–2004, the whole stock migrated north after spawning, leaving the regions in the southern Norwegian Sea void of herring. Since 2005 the oldest herring has again congregated in the south-western Norwegian Sea, in the frontal zone between the cooler East Icelandic water and the warmer Atlantic water. There was a significant positive relationship both between stock size and distribution area and between stock size and density. Moreover, it is likely that the strong year classes 1991/1992 and 1998/1999, which were relatively old when the respective changes in migration patterns occurred, were important contributors to the changes observed in 1999 and 2005, respectively.

Experimental results on the immune response to cancer indicate that activation of cytotoxic T lymphocytes (CTLs) through interactions with dendritic cells (DCs) can trigger a change in CTL migration patterns. In particular, while CTLs in the pre-activation state move in a non-local search pattern, the search pattern of activated CTLs is more localised. In this paper, we develop a kinetic model for such a switch in CTL migration modes. The model is formulated as a coupled system of balance equations for the one-particle distribution functions of CTLs in the pre-activation state, activated CTLs and DCs. CTL activation is modelled via binary interactions between CTLs in the pre-activation state and DCs. Moreover, cell motion is represented as a velocity-jump process, with the running time of CTLs in the pre-activation state following a long-tailed distribution, which is consistent with a Lévy walk, and the running time of activated CTLs following a Poisson distribution, which corresponds to Brownian motion. We formally show that the macroscopic limit of the model comprises a coupled system of balance equations for the cell densities, whereby activated CTL movement is described via a classical diffusion term, whilst a fractional diffusion term describes the movement of CTLs in the pre-activation state. The modelling approach presented here and its possible generalisations are expected to find applications in the study of the immune response to cancer and in other biological contexts in which switch from non-local to localised migration patterns occurs.

Migration is a global phenomenon. From time immemorial, man has been moving from one place to another for temporary or permanent settlements. This is largely facilitated by natural or artificial factors. The former include nat­ural disasters such as ecological change and draught, while the latter can be in­stigated by wars and search for better fortunes. This study examines the nature of the movements of the Okun-Yoruba people from the western region of Ni­geria to the confluence of the Niger and Benue rivers in the Central Geograph­ical Zone of Nigeria. It reveals how their long years of interactions with peoples of the confluence region were aided by the European delimitation of the area as part of the North, which has been the basis of sociopolltical agitation. The study reveals that Okun-Yoruba people, despite their geographical delimitation as northerners, see themselves more as southerners.