scholarly journals The Cytoskeleton—A Complex Interacting Meshwork

Cells ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 362 ◽  
Author(s):  
Hohmann ◽  
Dehghani
Keyword(s):  
Intermediate Filaments ◽  
Cellular Transport ◽  
Force Transmission ◽  
Animal Cells ◽  
Cytoskeletal Organization ◽  
Cellular Behavior ◽  
Cytoskeletal Filament ◽  
And Migration ◽  
External Forces ◽  
The Impact

The cytoskeleton of animal cells is one of the most complicated and functionally versatile structures, involved in processes such as endocytosis, cell division, intra-cellular transport, motility, force transmission, reaction to external forces, adhesion and preservation, and adaptation of cell shape. These functions are mediated by three classical cytoskeletal filament types, as follows: Actin, microtubules, and intermediate filaments. The named filaments form a network that is highly structured and dynamic, responding to external and internal cues with a quick reorganization that is orchestrated on the time scale of minutes and has to be tightly regulated. Especially in brain tumors, the cytoskeleton plays an important role in spreading and migration of tumor cells. As the cytoskeletal organization and regulation is complex and many-faceted, this review aims to summarize the findings about cytoskeletal filament types, including substructures formed by them, such as lamellipodia, stress fibers, and interactions between intermediate filaments, microtubules and actin. Additionally, crucial regulatory aspects of the cytoskeletal filaments and the formed substructures are discussed and integrated into the concepts of cell motility. Even though little is known about the impact of cytoskeletal alterations on the progress of glioma, a final point discussed will be the impact of established cytoskeletal alterations in the cellular behavior and invasion of glioma.

Cytoplasmic Intermediate Filaments in Cell Biology

2018 ◽  
Vol 34 (1) ◽  
pp. 1-28 ◽  
Author(s):  
Sandrine Etienne-Manneville
Keyword(s):  
Intermediate Filaments ◽  
Cell Biology ◽  
Expression Patterns ◽  
Major Elements ◽  
Cell Cortex ◽  
Cellular Functions ◽  
Specific Expression ◽  
Molecular Scaffold ◽  
And Migration ◽  
External Forces

Intermediate filaments (IFs) are one of the three major elements of the cytoskeleton. Their stability, intrinsic mechanical properties, and cell type–specific expression patterns distinguish them from actin and microtubules. By providing mechanical support, IFs protect cells from external forces and participate in cell adhesion and tissue integrity. IFs form an extensive and elaborate network that connects the cell cortex to intracellular organelles. They act as a molecular scaffold that controls intracellular organization. However, IFs have been revealed as much more than just rigid structures. Their dynamics is regulated by multiple signaling cascades and appears to contribute to signaling events in response to cell stress and to dynamic cellular functions such as mitosis, apoptosis, and migration.

Syrian Crisis and Migration

2015 ◽  
Vol 12 (3) ◽  
pp. 181-192 ◽  
Author(s):  
Pinar Yazgan ◽  
Deniz Eroglu Utku ◽  
Ibrahim Sirkeci
Keyword(s):  
Human Mobility ◽  
Special Issue ◽  
Host Countries ◽  
Syrian Crisis ◽  
Mass Migration ◽  
Large Numbers ◽  
And Migration ◽  
Europe Today ◽  
The Impact ◽  
Near Future

With the growing insurrections in Syria in 2011, an exodus in large numbers have emerged. The turmoil and violence have caused mass migration to destinations both within the region and beyond. The current "refugee crisis" has escalated sharply and its impact is widening from neighbouring countries toward Europe. Today, the Syrian crisis is the major cause for an increase in displacement and the resultant dire humanitarian situation in the region. Since the conflict shows no signs of abating in the near future, there is a constant increase in the number of Syrians fleeing their homes. However, questions on the future impact of the Syrian crisis on the scope and scale of this human mobility are still to be answered. As the impact of the Syrian crisis on host countries increases, so does the demand for the analyses of the needs for development and protection in these countries. In this special issue, we aim to bring together a number of studies examining and discussing human mobility in relation to the Syrian crisis.

Race, Gender, and Border Control in the Western Balkans

2018 ◽  
Author(s):  
Sanja Milivojević
Keyword(s):  
Knowledge Production ◽  
Asylum Seekers ◽  
Former Yugoslavia ◽  
Border Control ◽  
Western Balkans ◽  
Irregular Migrants ◽  
Criminological Inquiry ◽  
Gender And Migration ◽  
And Migration ◽  
The Impact

This chapter looks at the intersection of race, gender, and migration in the Western Balkans. Immobilizing mobile bodies from the Global South has increasingly been the focus of criminological inquiry. Such inquiry, however, has largely excluded the Western Balkans. A difficult place to research, comprising countries of the former Yugoslavia and Albania, the region is the second-largest route for irregular migrants in Europe (Frontex 2016). Indeed, EU expansion and global developments such as wars in Syria, Afghanistan, and Iraq have had a major impact on mobility and migration in the region. The chapter outlines racialized hierarchies in play in contemporary border policing in the region, and how these racialized and gendered practices target racially different Others and women irregular migrants and asylum seekers. Finally, this chapter maps the impact of such practices and calls for a shift in knowledge production in documenting and addressing such discriminatory practices.

scholarly journals Does Emancipation Matter? Fertility of Chinese International Migrants to the United States and Nonmigrants during China’s One-child Policy Period

2021 ◽  
pp. 019791832199478
Author(s):  
Wanli Nie ◽  
Pau Baizan
Keyword(s):  
United States ◽  
International Migration ◽  
Chinese Women ◽  
The United States ◽  
Selection Effects ◽  
Birth Cohorts ◽  
Family Policies ◽  
Chinese Migrants ◽  
And Migration ◽  
The Impact

This article investigates the impact of international migration to the United States on the level and timing of Chinese migrants’ fertility. We compare Chinese women who did not leave the country (non-migrants) and were subject to restrictive family policies from 1974 to 2015 to those who moved to the United States (migrants) and were, thus, “emancipated” from these policies. We theoretically develop and empirically test the emancipation hypothesis that migrants should have a higher fertility than non-migrants, as well as an earlier timing of childbearing. This emancipation effect is hypothesized to decline across birth cohorts. We use data from the 2000 US census, the 2005 American Community Survey, the 2000 Chinese census, and the 2005 Chinese 1 percent Population Survey and discrete-time event history models to analyze first, second, and third births, and migration as joint processes, to account for selection effects. The results show that Chinese migrants to the United States had substantially higher childbearing probabilities after migration, compared with non-migrants in China, especially for second and third births. Moreover, our analyses indicate that the migration process is selective of migrants with lower fertility. Overall, the results show how international migration from China to the United States can lead to an increase in migrant women’s fertility, accounting for disruption, adaptation, and selection effects. The rapidly increased fertility after migration from China to the United States might have implications on other migration contexts where fertility in the origin country is dropping rapidly while that in the destination country is relatively stable.

scholarly journals Analysis on Force Transmission Characteristics of Two-Legged Shield Support under Impact Loading

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Qing-liang Zeng ◽  
Zhao-sheng Meng ◽  
Li-rong Wan ◽  
Cheng-long Wang
Keyword(s):  
Structural Design ◽  
Load Transfer ◽  
Impact Load ◽  
Force Transmission ◽  
Full Account ◽  
Flexible Bodies ◽  
Powered Support ◽  
Structural Design Optimization ◽  
Hinge Points ◽  
The Impact

To study the load transfer characteristics of a two-legged shield powered support, a numerical simulation model of the support was established using the multibody dynamics software ADAMS. The model took full account of the hydraulic-elastic deformation characteristics of the support, as a series spring-damper system was used to replace the leg and the equilibrium jack. The canopy, goaf shield, lemniscate bars, and equilibrium jack are equivalent to flexible bodies. The setting force of the leg was provided by the preload of the equivalent spring, the static roof load was simulated using a slope signal, and the impact load was simulated using a step signal. Using the model, the impact and excitation effects of each hinge joint of the support were analyzed under different impact load conditions across the canopy. The results show that the location of the impact load affects the force transmissions of all hinge points of the support. Both the impact effect and the excitation effect are at a minimum when the impact force is located near the leg action line. These results are useful for the adaptive control and structural design optimization of the support.

Ciguapas in New York: Transcultural Ethnicity and Transracialization in Dominican American Performance

2012 ◽  
Vol 46 (1) ◽  
pp. 139-153 ◽  
Author(s):  
EMILIA MARÍA DURÁN-ALMARZA
Keyword(s):  
New York ◽  
Dominican Republic ◽  
Identity Formation ◽  
The Usa ◽  
And Migration ◽  
The 1960S ◽  
Definition Of ◽  
Dominican Women ◽  
The Impact ◽  
Dominican American

The Dominican American community in New York is perhaps one of the best examples of how processes of transculturation are affecting traditional definitions of ethnic identification. Given the intense economic, social and cultural transnational exchanges between the island and the USA from the 1960s, Dominicanyorks have been challenging the illusion of homogeneity in the definition of Americanness for decades, creating transnational social networks that transcend traditional national and ethnographic boundaries. The theatrical works of Josefina Báez, a Dominican American performer living in New York, and Sherezada (Chiqui) Vicioso, a Dominican poet and playwright who lived and worked in the US metropolis for decades before moving back to the Dominican Republic, lyrically explore issues of diaspora, identity and migration and the impact these phenomena might have in the lives of migrant Dominican women. Presenting diasporic experiences from two differing but interconnected locales – New York and the Dominican Republic – these plays offer two complementary views on the ways in which ethnicity, race, social class, age and geopolitical location interact in the formation of transcultural identities, thus contributing to develop a hemispheric approach to the study of identity formation in the Americas.

scholarly journals Effects of mechanical tension on protrusive activity and microfilament and intermediate filament organization in an epidermal epithelium moving in culture.

1986 ◽  
Vol 102 (4) ◽  
pp. 1400-1411 ◽  
Author(s):  
J Kolega
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Intermediate Filaments ◽  
Intermediate Filament ◽  
Mechanical Tension ◽  
Cytoskeletal Organization ◽  
Structural Support ◽  
Transmission Electron ◽  
Locomotive Activity ◽  
Filament Surface

Mechanical tension influences tissue morphogenesis and the synthetic, mitotic, and motile behavior of cells. To determine the effects of tension on epithelial motility and cytoskeletal organization, small, motile clusters of epidermal cells were artificially extended with a micromanipulated needle. Protrusive activity perpendicular to the axis of tension was dramatically suppressed. To determine the ultrastructural basis for this phenomenon, cells whose exact locomotive behavior was recorded cinemicrographically were examined by transmission electron microscopy. In untensed, forward-moving lamellar protrusions, microfilaments appear disorganized and anisotropically oriented. But in cytoplasm held under tension by micromanipulation or by the locomotive activity of other cells within the epithelium, microfilaments are aligned parallel to the tension. In non-spreading regions of the epithelial margin, microfilaments lie in tight bundles parallel to apparent lines of tension. Thus, it appears that tension causes alignment of microfilaments. In contrast, intermediate filaments are excluded from motile protrusions, being confined to the thicker, more central part of the cell. They roughly follow the contours of the cell, but are not aligned relative to tension even when microfilaments in the same cell are. This suggests that the organization of intermediate filaments is relatively resistant to physical distortion and the intermediate filaments may act as passive structural support within the cell. The alignment of microfilaments under tension suggests a mechanism by which tension suppresses protrusive activity: microfilaments aligned by forces exerted through filament-surface or filament-filament interconnections cannot reorient against such force and so cannot easily extend protrusions in directions not parallel to tension.

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