X-Ray Spectral Study of AGN Sources Content in Some Deep Extragalactic XMM-Newton Fields

We undertake a spectral study of a sample of bright X-ray sources taken from six XMM-Newton fields at high galactic latitudes, where AGN are the most populous class. These six fields were chosen such that the observation had an exposure time more than 60 ksec, had data from the EPIC-pn detector in the full-Frame mode and lying at high galactic latitude $|b| > 25^o$ . The analysis started by fitting the spectra of all sources with an absorbed power-law model, and then we fitted all the spectra with an absorbed power-law with a low energy black-body component model.The sources for which we added a black body gave an F-test probability of 0.01 or less (i.e. at 99% confidence level), were recognized as sources that display soft excess. We perform a comparative analysis of soft excess spectral parameters with respect to the underlying power-law one for sources that satisfy this criterion. Those sources, that do not show evidence for a soft excess, based on the F-test probability at a 99% confidence level, were also fitted with the absorbed power-law with a low energy black-body component model with the black-body temperature fixed at 0.1 and 0.2 keV. We establish upper limits on the soft excess flux for those sources at these two temperatures. Finally we have made use of Aladdin interactive sky atlas and matching with NASA/IPAC Extragalactic Database (NED) to identify the X-ray sources in our sample. For those sources which are identified in the NED catalogue, we make a comparative study of the soft excess phenomenon for different types of systems

Why Do States Develop Multi-tier Emigrant Policies? Evidence from Egypt

Why do states vary their policies towards their citizens abroad, and why are some emigrant groups treated preferentially to others? The literature on the politics of international migration has yet to explore this as a separate field of inquiry, assuming that states adopt a single policy that encourages, sustains or prevents emigration abroad. Yet, in the case of Egypt, the state developed a multi-tiered policy that distinctly favoured specific communities abroad over others. I hypothesise that policy differentiation is based upon the perceived utility of the emigrant group remaining abroad versus the utility of its return. This utility is determined by two factors: the sending state’s domestic political economy priorities and its foreign policy objectives

Egyptian Satirical Graphics on Social Media after the Arab Spring

This paper investigates Egyptian digital forms of satirical graphics mostly published on Social Media by cartoonists and amateurs after the Arab Spring. These include: webcomics memes, and Graphic Interchange Format (GIF). The paper will focus on two Facebook pages as a case study: Asa7be Sarcasm Society and Islam Gawish's Elwarka/The Paper. With this aim in mind, I will show how these forms of political satire incorporate, cinema, theatre, religion, western elements and pan-Arabism to express a political view in a creative manner to appeal to a more diverse and broad audience. The first part of the paper provides a brief discussion of Arabic/Egyptian satire with specific reference to political cartoons and Egyptian youth activism on social media (specifically Facebook). It will also introduce the concept of satirical graphics and some of its concrete applications. The second part describes the methodology and provides an analysis of the case study

Angst Springs Eternal:Dangerous Times and the Dangers of Timing the “Arab Spring”

Various reflections on the ‘Arab Spring’ evince a common view of the relationship between change and time that imbues events with a sense of intrinsic peril. Based on a framework developed from Norbert Elias’s concept of timing, this article elaborates the relationship between time and the ‘Arab Spring’ by unpacking and explaining three rhetorical tropes prevalent in academic responses to the revolts. The first two construct a problem to which the third proffers a solution. First, analysts treat time itself as a problematic force confounding stability and progress. Second, they deploy fluvial metaphors to present dynamic events as inherently insecure. Third, they use temporal Othering to retrofit the ‘Arab Spring’ to the familiar arc of liberal democracy, which renders the revolts intelligible and amenable to external intervention. These moves prioritize certainty and order over other considerations and constrain open-ended transformations within a familiar rubric of political progress. They also constitute an active timing effort based on a conservative standard, with important implications for our understanding of security and for scholarly reflexivity. The article concludes with three temporal alternatives for engaging novel changes like the ‘Arab Spring’

Polymeric Nanocomposite Hydrogel Scaffolds in Craniofacial Bone Regeneration: A Comprehensive Review

Nanocomposite biomaterials combine a biopolymeric matrix structure with nanoscale fillers. These bioactive and easily resorbable nanocomposites have been broadly divided into three groups, namely natural, synthetic or composite, based on the polymeric origin. Preparing such nanocomposite structures in the form of hydrogels can create a three-dimensional natural hydrophilic atmosphere pivotal for cell survival and new tissue formation. Thus, hydrogel-based cell distribution and drug administration have evolved as possible options for bone tissue engineering and regeneration. In this context, nanogels or nanohydrogels, created by cross-linking three-dimensional polymer networks, either physically or chemically, with high biocompatibility and mechanical properties were introduced as promising drug delivery systems. The present review highlights the potential of hydrogels and nanopolymers in the field of craniofacial tissue engineering and bone regeneration