migration pattern
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Author(s):  
Nevena Daković

The aim of this paper is to map manifold notions of migrant cinema and its history, in other words, film narratives about migrations from, across, and to the Balkans. The analysis looks at broader Balkan cinema that features as the context for focusing the changes of the migration pattern from and to Belgrade. The paper takes Practical Guide to Belgrade with Singing and Crying (Praktičan vodič kroz Beograd sa pevanjem i plakanjem, Bojan Vuletić, 2011) as its case study to show the recent reversal of migrant narratives in which the Balkans are the desired destination, in itself an exception to the rule. The analyses are based on the appropriated definition of migrant cinema and complemented with notions of inner exile and accented cinema.


2022 ◽  
Vol 208 ◽  
pp. 109505
Author(s):  
Kabir Shola Ahmed ◽  
Keyu Liu ◽  
Harouna Moussa ◽  
Jiangliang Liu ◽  
Hafizullah Abba Ahmed ◽  
...  

2021 ◽  
Author(s):  
Miaomiao Huang ◽  
Taiguo Liu ◽  
Shiqin Cao ◽  
Jonathan Yuen ◽  
Jiasui Zhan ◽  
...  

Puccinia striiformis f. sp. tritici is the causal agent of wheat yellow rust with records of regular and severe epidemics in China. This study explored the population dynamics of the yellow rust pathogen in Gangu, northwestern China. In Gangu, the Weihe River runs from west to east and divides Gangu into three regions: North and South mountain, with the valley in between. To study the genetic structure of the pathogen in local populations, samples were collected over 3 years from the three regions at different altitudes both within and between the wheat cropping seasons. A total of 811 P. striiformis f. sp. tritici isolates were successfully genotyped using 16 simple sequence repeat markers. The results suggest that P. striiformis f. sp. tritici can survive year-round in Gangu. The P. striiformis f. sp. tritici populations migrated among the regions, and the migration pattern was not related to altitude. The oversummering populations in the North and South mountain regions were genetically different from each other; and the P. striiformis f. sp. tritici populations collected from the lower altitude in the valley had no relationship with any of the populations collected in the spring or fall, indicating that they too have a different origin. Signatures of random mating were found in the populations collected in both North and South mountain regions, but not in the valley populations.


2021 ◽  
Vol 2 ◽  
Author(s):  
Rafael Jose Vivero-Gomez ◽  
Gustavo Bedoya Mesa ◽  
Jorge Higuita-Castro ◽  
Sara M. Robledo ◽  
Claudia X. Moreno-Herrera ◽  
...  

Gram-negative bacteria are known to use a quorum sensing system to facilitate and stimulate cell to cell communication, mediated via regulation of specific genes. This system is further involved in the modulation of cell density and metabolic and physiological processes that putatively either affect the survival of insect vectors or the establishment of pathogens transmitted by them. The process of quorum sensing generally involves N-acyl homoserine lactones and 2-alkyl-4-quinolones signaling molecules. The present study aimed to detect and identify quorum sensing signaling molecules of AHLs and AHQs type that are secreted by intestinal bacteria, and link their production to their extracellular milieu and intracellular content. Isolates for assessment were obtained from the intestinal tract of Pintomyia evansi (Leishmania insect vector). AHLs and AHQs molecules were detected using chromatography (TLC) assays, with the aid of specific and sensitive biosensors. For identity confirmation, ultra-high-performance liquid chromatography coupled with mass spectrometry was used. TLC assays detected quorum sensing molecules (QSM) in the supernatant of the bacterial isolates and intracellular content. Interestingly, Pseudomonas otitidis, Enterobacter aerogenes, Enterobacter cloacae, and Pantoea ananatis isolates showed a migration pattern similar to the synthetic molecule 3-oxo-C6-HSL (OHHL), which was used as a control. Enterobacter cancerogenus secreted C6-HSL, a related molecules to N-hexanoyl homoserine lactone (HHL), while Acinetobacter gyllenbergii exhibited a migration pattern similar to 2-heptyl-4-quinolone (HHQ) molecules. In comparison to this, 3-oxo-C12-HSL (OdDHL) type molecules were produced by Lysobacter soli, Pseudomonas putida, A. gyllenbergii, Acinetobacter calcoaceticus, and Pseudomonas aeruginosa, while Enterobacter cloacae produced molecules similar to 2-heptyl-3-hydroxy-4-quinolone (PQS). For Pseudomonas putida, Enterobacter aerogenes, P. ananatis, and Pseudomonas otitidis extracts, peak chromatograms with distinct retention times and areas, consistent with the molecules described in case of TLC, were obtained using HPLC. Importantly, P. ananatis produced a greater variety of high QSM concentration, and thus served as a reference for confirmation and identification by UHPLC-MRM-MS/MS. The molecules that were identified included N-hexanoyl-L-homoserine lactone [HHL, C10H18NO3, (M + H)], N-(3-oxohexanoyl)-L-homoserine lactone [OHHL, C10H16NO4, (M + H)], N-(3-oxododecanoyl)-L-homoserine lactone [OdDHL, C16H28NO4, (M + H)], and 2-heptyl-3-hydroxy-4(1H)-quinolone [PQS, C16H22NO2, (M + H)]. Besides this, the detection of diketopiperazines, namely L-Pro-L-Tyr and ΔAla-L-Val cyclopeptides was reported for P. ananatis. These molecules might be potentially associated with the regulation of QSM system, and might represent another small molecule-mediated bacterial sensing system. This study presents the first report regarding the detection and identification of QSM and diketopiperazines in the gut sand fly bacteria. The possible effect of QSM on the establishment of Leishmania must be explored to determine its role in the modulation of intestinal microbiome and the life cycle of Pi. evansi.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12412
Author(s):  
Keita Koeda ◽  
Hideyuki Touma ◽  
Katsunori Tachihara

Background Although the biomass of the nocturnal fishes is almost same as that of diurnal fishes, most of the ecological studies that examine feeding or reproductive behaviors are on diurnal fishes. Therefore, there is limited ecological information regarding the nocturnal fishes. This fact may be attributed to the difficulty in observing them during darkness. Members of the genus Pempheris (Pempheridae) are one of the most abundant nocturnal fishes on coral reefs. Methods The nighttime migrations of Pempheris schwenkii were observed by attaching a chemical luminescent tag. Tagged fishes were followed by an observer without torch and SCUBA, and their positions and estimated depths were plotted on an underwater topographic map. Aquarium tank observation was carried out to further describe their habits during the night. Results The new tagging method provided good data for observing the migration behavior. In all five observations, the target fishes started nighttime migration from the entrance of their cave within 1 h after sunset. All of them immediately left the inner reef and spent most of the observation time near the surface (0–5 m depth) or shallow (5–15 m depth) water-columns of the outer reef. Their migration pattern varied between days, but they migrated long distance (379–786 m/h) during each observation. The behavior observed in the aquarium tank was categorized into five patterns: schooling, shaking, migrating, spawning, and feeding. Shaking and spawning were observed during one of three observation days. Discussion The present study firstly clarified the small-scale but dynamic nocturnal migration pattern of P. schwenkii in nature by a new method using chemical luminescent tags. In addition, combined observations from nature and an aquarium could be used to estimate the behavior of this species. Pempheris schwenkii may reduce their predation risk of eggs and adults by spawning at outer reef in nighttime. It was estimated that they can potentially migrate 4–7 km/night. The rapid growth known for this species may have been supported by their feeding behavior where they can fill up their stomach every night with rich zooplankton in outer reefs. Furthermore, the behavior of this species indicates the possibility that they make an important contribution to the flow of energy and materials in their coral reef ecosystem.


Geosphere ◽  
2021 ◽  
Author(s):  
Jacob A. Covault ◽  
Zoltán Sylvester ◽  
Can Ceyhan ◽  
Dallas B. Dunlap

Submarine channels are conduits for sediment delivery to continental margins, and channel deposits can be sandy components of the fill in tectonically active salt basins. Examples of salt-withdrawal basin fill commonly show successions of sandy channelized or sheet-like systems alternating with more mud-rich mass-transport complexes and hemipelagites. This alternation of depositional styles is controlled by subsidence and sediment-supply histories. Salt-basin fill comprising successions of largely uninterrupted meandering-channel deposition are less commonly recognized. This begs the questions: can sediment supply be large enough to overwhelm basin subsidence and result in a thick succession of channel deposits, and, if so, how would such a channel system evolve? Here, we use three-dimensional seismic-reflection data from a >1500 km2 region with salt-influenced topography in the Campos Basin, offshore Brazil, to evaluate the influence of salt diapirs on an Upper Cretaceous–Paleogene giant meandering submarine-channel system (channel elements >1 km wide; meander wavelengths several kilometers to >10 km). The large scale of the channels in the Campos Basin suggests that sediment discharge was large enough to sustain the meandering channel system in spite of large variability in subsidence across the region. We interpreted 22 channel centerlines to reconstruct the detailed kinematic evolution of this depositional system; this level of detail is akin to that of recent studies of meandering fluvial channels in time-lapse Landsat satellite images. The oldest channel elements are farther from salt diapirs than many of the younger ones; the centerlines of the older channel elements exhibit a correlation between curvature and migration rate, and a spatial delay between locations of peak curvature and maximum migration distance, similar to that observed in rivers. As many of the younger channel centerlines expanded toward nearby salt diapirs, their migration pattern switched to downstream translation as a result of partial confinement. Channel segments that docked against salt diapirs became less mobile, and, as a result, they do not show a correlation between curvature and migration rate. The channel migration pattern in the Campos Basin is different compared to that of a tectonically quiescent continental rise where meander evolution is unobstructed. This style of channelized basin filling is different from that of many existing examples of salt-withdrawal minibasins that are dominated by overall less-channelized deposits. This difference might be a result of the delivery of voluminous coarse sediment and high discharge of channel-forming turbidity currents to the Campos Basin from rivers draining actively uplifting coastal mountains of southeastern Brazil. Detailed kinematic analysis of such well-preserved channels can be used to reconstruct the impact of structural deformation on basin fill.


2021 ◽  
Author(s):  
Stephan J. Holtkamp ◽  
Louise M. Ince ◽  
Coline Barnoud ◽  
Madeleine T. Schmitt ◽  
Flore Sinturel ◽  
...  

AbstractMigration of leukocytes from the skin to lymph nodes (LNs) via afferent lymphatic vessels (LVs) is pivotal for adaptive immune responses1,2. Circadian rhythms have emerged as important regulators of leukocyte trafficking to LNs via the blood3,4. Here, we demonstrate that dendritic cells (DCs) have a circadian migration pattern into LVs, which peaks during the rest phase in mice. This migration pattern is determined by rhythmic gradients in the expression of the chemokine CCL21 and of adhesion molecules in both mice and humans. Chronopharmacological targeting of the involved factors abrogates circadian migration of DCs. We identify cell-intrinsic circadian oscillations in skin lymphatic endothelial cells (LECs) and DCs that cogovern these rhythms, as their genetic disruption in either cell type ablates circadian trafficking. These observations indicate that circadian clocks control the infiltration of DCs into skin lymphatics, a process that is essential for many adaptive immune responses and relevant for vaccination and immunotherapies.


2021 ◽  
Vol 45 (2) ◽  
pp. 229-253
Author(s):  
Jovana Mastilovic ◽  
Marco Zoppi

Abstract This article examines a migration pattern which has been overshadowed by the ‘security turn’ dominating European discourses: depopulation. Across Europe, emigration is responsible for significant demographic transformations, especially in rural and remote areas. Depopulation leads to the reduction of services provided to citizens, further diminishing the attractiveness of these territories. Against this background, migration can counterbalance depopulation as part of a strategy for rural regeneration. This article analyses the case of Riace, an Italian town that has been hosting people seeking asylum and refugees for decades, and compares it to the Serbian town of Sjenica, where increasing numbers of non-EU migrants are settling after the ‘closure’ of the Western Balkans route. Our empirical findings indicate that there is both an opportunity and a political will to implement a similar model to that of Riace in Sjenica and in the southwest Sandžak region.


2021 ◽  
Author(s):  
Daniel A. Rende

Jewish Thornhill, located in Vaughan, York Region, was intentionally designed and planned as a walkable Jewish suburb. Though it is an auto-oriented suburb, Thornhill is also a walkable neighbourhood that caters to the distinct needs of its large Jewish community. Orthodox Jews require ready access to kosher food; they also require synagogues within walking distance as they do not drive cars or take transit on the Sabbath or Jewish holidays. The master planning of Thornhill was made possible by developers who recognized the Jewish community’s predictable migration pattern along Bathurst Street and purchased land in Thornhill two decades before the Jewish community had reached Thornhill. Topics that were researched for this paper included walkability, Toronto’s Jewish history, the intersection of religion and urban planning, and smart growth.


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