Being in limbo: Digital Habitus and Contemporary Colonialism in the Case of Syrian Refugees in Turkey, Greece, and Germany

This study discusses Syrian refugees’ migration trajectories and narratives, based on the fieldwork conducted among Syrian refugees in Turkey, Greece, and Germany as three major geo-political countries particularly concerning Syrian refugee communities. The research adopts a qualitative research map, using the Grounded Theory research approach, ethnography and semi-structured interview methods, in six cities and eight refugee protection centres and camps. The research findings obtained and generated during the field studies are evaluated and analysed using theoretical toolboxes derived from sociology and political science. Especially important are three theoretical frameworks: Power Relations, Digital Habitus, and Political and Social Subjectivities, through which I analysed the Syrian refugees’ practices of mobilities, migration routes, and perception of targeted countries in detail. These theoretical frameworks assist in understanding the implications and limitations of power relations in refugees’ lives, as well as refugees’ use of the internet and media and the influence of these uses on their refugee’s perceptions and desires while being in limbo in refugee camps. Also, the importance of varying capital forms and women refugee’s gender experiences in forced migration and displacement are foregrounded and evaluated. The research proposes a new methodological system that helps to understand contemporary colonialism while addressing current colonial and exploitation relations - Semi-Autonomous Colonialism. This system considers three mechanisms as (co)-operating drivers: Power relations as pushing and formative forces, Subjectivity as individuals’ agencies, actions, and representations within the scope of their own capacity and capital, and Digital Habitus as a new connecting interface, that assist in understanding refugees’ use of the internet and media and its influence of on the refugee's perception and desires. In the research, in which the active participation of individuals by consenting to the changing and digitalising systems is discussed, semi-autonomy stands out as a unique character. Contemporary colonialism appears in peoples' agenda even in the daily practices and decisions, particularly when they immigrate, establish a new life and become unseen actors in economic and social relationships. Consequently, Semi-Autonomous Colonialism is a model of modern colonialism in which the strategies and mechanisms of exploitation become invisible. Keywords: Migration, Forced Displacement, Syrian Refugees, Colonialism, Habitus, Power Relations, Subjectivit

How coenzyme B12 radicals are generated: the crystal structure of methylmalonyl-coenzyme A mutase at 2 å resolution

AbstractBackground: The enzyme methylmalonyl-coenzyme A (CoA) mutase, an αβ heterodimer of 150 kDa, is a member of a class of enzymes that uses coenzyme B12 (adenosylcobalamin) as a cofactor. The enzyme induces the formation of an adenosyl radical from the cofactor. This radical then initiates a free-radical rearrangement of its substrate, succinyl-CoA, to methylmalonyl-CoA.Results Reported here is the crystal structure at 2 å resolution of methylmalonyl-CoA mutase from Propionibacterium shermanii in complex with coenzyme B12 and with the partial substrate desulpho-CoA (lacking the succinyl group and the sulphur atom of the substrate). The coenzyme is bound by a domain which shares a similar fold to those of flavodoxin and the B12-binding domain of methylcobalamin-dependent methionine synthase. The cobalt atom is coordinated, via a long bond, to a histidine from the protein. The partial substrate is bound along the axis of a (β/α)8 TIM barrel domain.Conclusion The histidine–cobalt distance is very long (2.5 å compared with 1.95–2.2 å in free cobalamins), suggesting that the enzyme positions the histidine in order to weaken the metal–carbon bond of the cofactor and favour the formation of the initial radical species. The active site is deeply buried, and the only access to it is through a narrow tunnel along the axis of the TIM barrel domain

T-Cell Receptor/CD28-Mediated Activation of Human T Lymphocytes Induces Expression of Functional -Opioid Receptors

ABSTRACT Opiates function as immunomodulators, partly by their effects on T cells. Opioids act via -, ␦-, and -opioid receptors, among which the -type is of particular interest, because morphine-like opioids preferentially bind to it. Here we report that -opioid receptor mRNA was induced after CD3/28-mediated activation of primary human T lymphocytes and Jurkat T cells, neither of which expresses the gene constitutively. Moreover, a reporter gene construct containing 2624 base pairs of the -opioid receptor promoter was transactivated by CD3/28 stimulation. Transcriptional induction of the -opioid receptor gene was mediated by activator protein-1 (AP-1), nuclear factor-B, and nuclear factor of activated T cells (NFAT). NFAT was found to bind to three sequences of the -opioid receptor promoter, located at nucleotides Ϫ1064, Ϫ785, and Ϫ486. Although the Ϫ486 element is in close proximity to a putative AP-1 site, there was no evidence for a combined AP-1/NFAT site. Furthermore, we demonstrated that the induction of interleukin-2 mRNA and protein in activated T cells was inhibited by morphine in cells, in which -opioid receptors had been induced by CD3/28 monoclonal antibodies (mAbs), and that this effect was blocked by the -opioid receptor-specific antagonist D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH 2 . CD3/28 mAb-induced interleukin-2 transcription was also inhibited by the opioids fentanyl and loperamide. This indicates that the induced -opioid receptor mRNA is translated into functional receptor protein. Furthermore, a -opioid receptor-enhanced green fluorescent protein-fusion protein was localized in membranes of Jurkat cells and internalized in response to [D-Ala 2 ,NMe-Phe 4 ,Gly 5 -ol]-enkephalin but not morphine. In conclusion, these data emphasize the role of opioids in the modulation of T lymphocyte signaling

Direct and inverse pumping in flows with homogeneous and non-homogeneous swirl

The conditions in which meridional recirculations appear in swirling flows above a fixed wall are analysed. In the classical Bodew\"adt problem, where the swirl tends towards an aysmptotic value away from the wall, the well-known "tea-cup effect" drives a flow away from the plate at the centre of the vortex. Simple dimensional arguments applied to a single vortex show that if the intensity of the swirl decreases away from the wall, the sense of the recirculation can be inverted, and that the associated flow rate scales with the swirl gradient. Only if the flow is quasi-2D, does the classical tea-cup effect take place. This basic theory is confirmed by numerical simulations of a square array of steady, electrically driven vortices. Experiments in the turbulent regimes of the same configuration reveal that these mechanisms are active in the average flow and in its fluctuating part. The mechanisms singled out in this letter provide an explanation for previously observed phenomena in electrolyte flows. They also put forward a possible mechanism for the generation of helicity in flows close to two-dimensionality, which plays a key role in the transition between 2D and 3D turbulence

A Performant, Misuse-Resistant API for Primality Testing

Primality testing is a basic cryptographic task. But developers today are faced with complex APIs for primality testing, along with documentation that fails to clearly state the reliability of the tests being performed. This leads to the APIs being incorrectly used in practice, with potentially disastrous consequences. In an effort to overcome this, we present a primality test having a simplest-possible API: the test accepts a number to be tested and returns a Boolean indicating whether the input was composite or probably prime. For all inputs, the output is guaranteed to be correct with probability at least 1 - 2-128. The test is performant: on random, odd, 1024-bit inputs, it is faster than the default test used in OpenSSL by 17%. We investigate the impact of our new test on the cost of random prime generation, a key use case for primality testing. The OpenSSL developers have adopted our suggestions in full; our new API and primality test are scheduled for release in OpenSSL 3.0

A vector-valued ground motion intensity measure incorporating normalized spectral area

A vector-valued intensity measure is presented, which incorporates a relative measure represented by the normalized spectral area. The proposed intensity measure is intended to have high correlation with specific relative engineering demand parameters, which collectively can provide information regarding the damage state and collapse potential of the structure. Extensive dynamic analyses are carried out on a single-degree-of-freedom system with a modified Clough–Johnston hysteresis model, using a dataset of 40 ground motions, in order to investigate the proposed intensity measure characteristics. Response is expressed using the displacement ductility, and the normalized hysteretic energy, both of which are relative engineering demand parameters. Through regression analysis the correlation between the proposed intensity measure and the engineering demand parameters is evaluated. Its domain of applicability is investigated through parametric analysis, by varying the period and the strain-hardening stiffness. Desirable characteristics such as efficiency, sufficiency, and statistical independence are examined. The proposed intensity measure is contrasted to another one, with respect to its correlation to the engineering demand parameters. An approximate procedure for estimating the optimum normalized spectral area is also presented. It is demonstrated that the proposed intensity measure can be used in intensity-based assessments, and, with proper selection of ground motions, in scenario-based assessments