Investigating the influence of a powder compact's geometry on its pore structure and optical properties using terahertz spectroscopy

In this study, terahertz time domain spectroscopy (THz-TDS) is used to analyze how the geometry of a compact affects its pore structure (pore shape and orientation). By using flat-faced and biconvex compacts, it was evident from our analysis that pores tend to assume specific shapes and orientations based on the compact's geometry and this was found to significantly affect the extracted optical properties of samples prepared by mixing a material with polyethylene (PE) as diluent and subsequent compaction. However, such sensitivity to the pore properties opens a number of industrial applications such as for quality testing of pharmaceutical tablets. A comparison made between the PE based compacts and a set of pharmaceutical tablets prepared from the same formulation has revealed that flatfaced and biconvex compacts possess different pore geometries and hence different optical properties

3D Bioelectronic Model of the Human Intestine

Organ on chip (OoC) technologies have the potential to improve the translation of promising therapies currently failing in clinical trials at great expense and time due to dissimilarities between animal and human biology. Successful OoC models integrate human cells within 3D tissues with surrounding biomolecular components, and have benefited from the use of inert 3D gels and scaffolds used as templates, prompting tissue formation. However, monitoring technologies used to assess tissue integrity and drug effects are ill adapted to 3D biology. Here, a tubular electroactive scaffold serves as a template for a 3D human intestine, and enables dynamic electrical monitoring of tissue formation over 1 month. Cell- and extracellular matrix component-invoked changes in the properties of the scaffold alleviate the need for posthoc placement of invasive metallic electrodes or downstream analyses. Formation of in vivo-like stratified and polarized intestinal tissue compete with lumen contrasts with other quasi3D models of the intestine using rigid porous membrane to separate cell types. These results provide unprecedented real-time information on tissue formation with highly sensitive multimodal operation, thanks to dual electrode and transistor operation. This device and the methodology for tissue growth within it represents a paradigm shift for disease modeling and drug discover

Management of Extremity Venous Thrombosis in Neonates and Infants: An Experience From a Resource Challenged Setting

We aimed to evaluate the outcome of different treatment modalities for extremity venous thrombosis (VT) in neonates and infants, highlighting the current debate on their best tool of management. This retrospective study took place over a 9-year period from January 2009 to December 2017. All treated patients were referred to the vascular and pediatric surgery departments from the neonatal intensive care unit. All patients underwent a thorough history-taking as well as general clinical and local examination of the affected limb. Patients were divided into 2 groups: group I included those who underwent a conservative treated with the sole administration of unfractionated heparin (UFH), whereas group II included those who were treated with UFH plus warfarin. Sixty-three patients were included in this study. They were 36 males and 27 females. Their age ranged from 3 to 302 days. Forty-one (65%) patients had VT in the upper limb, whereas the remaining 22 (35%) had lower extremity VT. The success rate of the nonsurgical treatment was accomplished in 81% of patients. The remaining 19% underwent limb severing, due to established gangrene. The Kaplan-Meier survival method revealed a highly significant increase in both mean and median survival times in those groups treated with heparin and warfarin compared to heparin-only group (P < .001). Nonoperative treatment with anticoagulation or observation (ie, wait-and-see policy) alone may be an easily applicable, effective, and a safe modality for management of VT in neonates and infants, especially in developing countries with poor or highly challenged resource settings

Shear stress distribution within narrowly constrained structured grains and granulated powder beds

An experimental study is presented here to understand the stress transmission characteristics under different geometrical arrangements of particulates inside a narrow chamber subjected to axial compression loading. The multi-grain systems considered here are face-centred, simple cubic and poly-dispersed structures, as well as inclusions embedded inside seeded, unseeded and cohesive powder bed of Durcal (calcium carbonate). The distribution of the maximum shear stress, direction of the major principal stress and shear stress concentration factor were obtained using photo stress analysis tomography (PSAT). The results show that the maximum shear stress distribution in the simple cubic structure is chain-like and self-repetitive, i.e, a single grain behaviour is representative of the whole system. This is not the case in the case of other granular packing. In the case of the inclusion surrounded by powder media, the maximum shear stress distribution in the inclusion occurs through ring-like structures, which are different from those observed in the structured granular packing. This tendency increases for an increase in the cohesivity of the surrounding particulates. In the granular systems, the direction of the major principal stress is mostly orthogonal to the direction of loading except in some particles in the random granular packing. In the case of inclusion surrounded by Durcal particulates, the directional of the major principal stress acts along the direction of the axial loading except in the ring region where this tends to be oblique to the direction of axial loading. Estimates of the shear stress concentration factor (k) show that, k tends to be independent of the structural arrangement of granular packing at higher load levels. In the case of inclusion surrounded by powder bed, k for the seeded granulated particulate bed is mostly independent of the external load levels. In the case of unseeded particulate (granulated) bed, a fluctuation in k is observed with the loading level. This suggests that the seeded granules could distribute stresses in a stable manner without much change in the nature of shear stress-transmitting fabric of the particulate contacts under external loading. An increase in the cohesion of particulate bed results in more plastic deformation as shown by the differential shear stress concentration factor. The results reported in this study show the usefulness of optical stress analysis to shed some scientific lights on unravelling some of the complexities of particulate systems under different structural arrangements of grains and surrounding conditions of the inclusions in particulate media

The Patriarchal Bargain in a Context of Rapid Changes to Normative Gender Roles: Young Arab Women’s Role Conflict in Qatar

Social norms in patriarchal countries in the Middle East are changing at differing rates. In Qatar, expectations about education have shifted, and women’s participation in higher education is normative. However, women’s participation in the workforce remains relatively low, and women still are expected to perform all household and child-rearing activities. Interviews with 27 18–25 year-old Qatari women enrolled in college in Qatar are used to illustrate the conflict between norms about education, workforce, and family. Many young women resolve this normative conflict by giving preference to family over work and education. Other women hold conflicting norms and goals for their future without acknowledging the normative conflict. Overall, young women in this sample feared divorce, were uncertain about customary family safety nets, and thus desired financial independence so they would be able to support themselves if they were left alone later in life due to divorce, or the death of their husband. The Qatari government should revisit the appropriateness of continuing to emphasize the patriarchal family structure and socially conservative family norms, if they desire to advance women in their society

Exploring Takfir, Its Origins and Contemporary Use: The Case of Takfiri Approach in Daesh’s Media

Muslims have been the primary targets of Daesh’s attacks since 2014 in different countries such as Afghanistan, Iraq, and Syria. These attacks were based on its takfiri ideology. As Daesh official media and documents indicate, kufr (unbelief, infidelity) in Daesh’s approach is not limited to non-Muslims (original disbelievers), but Muslims are the most significant parts of kuffar (unbelievers) in its view and defined as incidental disbelievers. Through studying Daesh’s official documents and various Arabic, English, and Persian media productions, in an explanatory research, this article attempts to display Daesh’s takfiri approach toward Muslims and explains its historical and ideological roots, difference with Al-Qaeda’s takfiri approach, different approaches to takfir inside Daesh, main targets of Daesh’s takfir, and the reasons behinds its takfiri view. This article displays that for Daesh, the Muslims are limited only to Sunni Muslims who are accepting and following its approach. Other Sunni and non-Sunni Muslims are thus kuffar. This study also shows that the assertion of takfir has become a method for Daesh to discredit its opponents, such as Shi’a Muslims and other Muslim groups

Some psychosocial and cultural factors in the Arab-Israeli conflict: a review of the literature

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66497/2/10.1177_002200277201600210.pd

Contextualizing privilege and disadvantage: lessons from women expatriates in the Middle East

This article explores how the simultaneity of privilege and disadvantage shapes the experiences of women expatriates in the Middle East. The article problematizes the simultaneity of being an elite group (e.g. expatriates) and a disadvantaged group (e.g. women) within the context of Gulf Cooperation Council countries. Drawing on the literature about women and work expatriation, the article analyses the narratives of women expatriates to highlight the complexity and multidimensionality of their experiences, positioning the discussion within the framework of gendered institutions. The article concludes that privilege and disadvantage are inseparable to the way the experiences of women expatriates unfold in the Middle East, and that institutional settings articulate this inseparability in order to regulate and help to maintain the gender social order. The article contributes a nuanced understanding of the experiences of women expatriates, challenging dominant views that present this group as generally privileged by virtue of their skilled and mobile status