Search results for "Migration"

Electron beam induced growth of silver nanowhiskers

2015

Abstract In this paper we report an electron beam induced rapid (up to several tens of nm/s) growth of silver nanowhiskers from silver nanowire networks coated with TiO 2 by sol–gel method. Different growth conditions are tested and it is demonstrated that growth is optimal for samples with the film thickness in the range 50–200 nm and previously annealed at 400 °C for 5–10 min. Growth mechanism is attributed to cooperative effect of several factors including diffusion of Ag into TiO 2 matrix during annealing, electromigration of Ag atoms caused by strong electric field, and presence of mechanical stresses at interfaces enhanced by thermal expansions due to local heating under e-beam illumi…

Emotions and epistemology: a path for reconsideration in the 21st century

2017

The present paper explores the gap between sensations and emotions in the global capitalism. We held the thesis that there are diverse ways to systematise the theoretical orientations on which the studies on the body/emotion are based; a possible one, having in mind the Latin American context and without intent of exhaustiveness, is the following: a) a line of work connected to Foucault and his concepts of control, discipline, and technologies of the self; b) an approach connected to Bourdieu and his notions of habitus, body hexis, and social fields; c) a set of investigations in the field of biopolitics referring to Esposito and Agamben on the one hand, and to Negri and Hardt on the other;…

Narrating Migration

2017

Numerous studies evidence how migration represents a critical event in the subject’s life (Akhtar , 1999; Baptiste , 1987; Scabini & Rossi , 2008). Such an event is characterised by various phases, some of which reflect the loss of culture, family of origin, language and some of which concern adaptation to the new environment (Hertz, 1981, 1993; Kaёs, 1993; Sluzky, 1992). To foster routes of growth and constructive interaction with the new environment, it is necessary for immigrants to strengthen the process of self-awareness. This is fundamental if learning is to be considered transformative (Freire, 1970). According to what is proposed in this paper, such a process of self-awareness i…

Spazi e narrazione: un'odissea

2011

Cooperation and cultural transmission in a coordination game

2009

Abstract The aim of this paper is to analyze if cooperation can be the product of cultural evolution in a two-stage coordination game, consisting of a production stage followed by a negotiation phase. We present an overlapping generations model with cultural transmission of preferences where the distribution of preferences in the population and the strategies are determined endogenously and simultaneously. There are several groups in the society; some of them play cooperatively and others do not. Socialization takes place inside the group, but there is a positive rate of migration among groups which parents anticipate. Our main result shows that all groups converge to the cooperative equili…

Identity, origin, and migration of peripheral glial cells in the Drosophila embryo.

2008

Glial cells are crucial for the proper development and function of the nervous system. In the Drosophila embryo, the glial cells of the peripheral nervous system are generated both by central neuroblasts and sensory organ precursors. Most peripheral glial cells need to migrate along axonal projections of motor and sensory neurons to reach their final positions in the periphery. Here we studied the spatial and temporal pattern, the identity, the migration, and the origin of all peripheral glial cells in the truncal segments of wildtype embryos. The establishment of individual identities among these cells is reflected by the expression of a combinatorial code of molecular markers. This allows…

Netrins guide migration of distinct glial cells in the Drosophila embryo

2010

Development of the nervous system and establishment of complex neuronal networks require the concerted activity of different signalling events and guidance cues, which include Netrins and their receptors. In Drosophila, two Netrins are expressed during embryogenesis by cells of the ventral midline and serve as attractant or repellent cues for navigating axons. We asked whether glial cells, which are also motile, are guided by similar cues to axons, and analysed the influence of Netrins and their receptors on glial cell migration during embryonic development. We show that in Netrin mutants, two distinct populations of glial cells are affected: longitudinal glia (LG) fail to migrate medially …

Neurogenesis in adult subventricular zone

2002

Much excitement has been generated by the identification of adult brain regions harboring neural stem cells and their continual generation of new neurons throughout life. This is an important departure from traditional views of the germinal potential of the postnatal brain. However, a more profound

L-selectin regulates human neutrophil transendothelial migration

2021

ABSTRACT The migration of circulating neutrophils towards damaged or infected tissue is absolutely critical to the inflammatory response. L-selectin is a cell adhesion molecule abundantly expressed on circulating neutrophils. For over two decades, neutrophil L-selectin has been assigned the exclusive role of supporting tethering and rolling – the initial stages of the multi-step adhesion cascade. Here, we provide direct evidence for L-selectin contributing to neutrophil transendothelial migration (TEM). We show that L-selectin co-clusters with PECAM-1 – a well-characterised cell adhesion molecule involved in regulating neutrophil TEM. This co-clustering behaviour occurs specifically during …

The evolution of the European Union law on the criminalization of humanitarian assistance to irregular migrants: From the council directive 2002/90/C…

2021

With the new Pact on Migration and Asylum, the European Commission published the Guidance C(2020) 6470 of 23 September 2020 on the implementation of EU rules on definition and prevention of the facilitation of unauthorised entry, transit and residence. The present contribution shows as this guidance proposes an interpretation of the article 1 of the Council Directive 2002/90/CE, which only partially meets the problem of the criminalization of humanitarian assistance to irregular migrants, since it has shortcomings both at material and at formal level. After an analysis concerning the guidance capacity to impact on the Court of Justice and national judges case-law, the article ends with some…