Generality of shear thickening in suspensions

Suspensions are of wide interest and form the basis for many smart fluids. For most suspensions, the viscosity decreases with increasing shear rate, i.e. they shear thin. Few are reported to do the opposite, i.e. shear thicken, despite the longstanding expectation that shear thickening is a generic type of suspension behavior. Here we resolve this apparent contradiction. We demonstrate that shear thickening can be masked by a yield stress and can be recovered when the yield stress is decreased below a threshold. We show the generality of this argument and quantify the threshold in rheology experiments where we control yield stresses arising from a variety of sources, such as attractions from particle surface interactions, induced dipoles from applied electric and magnetic fields, as well as confinement of hard particles at high packing fractions. These findings open up possibilities for the design of smart suspensions that combine shear thickening with electro- or magnetorheological response.Comment: 11 pages, 9 figures, accepted for publication in Nature Material

On the source, site and modes of domination

This article seeks to examine how domination manifests in social relationships and institutions. It does this by examining two debates in republican literature. The first of which is whether domination requires institutionalisation? This addresses the source of domination. The second debate is on the nature of arbitrary power. This raises questions about the site of domination. It will be argued that the source of domination can be personally or socially constituted and that the site can be interactional or systemic. This yields four modes of domination that can be used to examine social institutions and relationships

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

The Chameleon-Like Properties of Psychoactive Drugs: Examinations with HR LC-MS/MS Technology of Patients Presenting at the Emergency Department Following the Use of Synthetic Cannabinoids: A Case Series and Literature Review

The chameleon can disguise itself in nature by taking on different colors and forms. As synthetic cannabinoids (SC) have clinically similar effects to those of several psychoactive agents, they are one of the most difficult intoxications to diagnose. The reasons for this are due to clinical variations throughout the world and the differences in symptoms having not been determined due to their similarity to the intoxication of several other drugs. The aim of this study was to obtain prospective data of patients presenting at the Emergency Department (ED) with suspected SC intoxication, and as a result of prospective examination of samples, to determine a new generation of SC use, SC types, clinical findings, and treatments. Method: A total of a 15 patients with suspected SC intoxication who presented at the ED of the Health Sciences University Kayseri Training and Research Hospital between January 2017 and January 2018 were examined. Samples taken prospectively from patients who were followed-up for a diagnosis of SC intoxication were examined with the HR LC-MS/MS method; SC were determined, and the test results of other psychoactive agents that were used concurrently were examined. Conclusions: Three significant findings emerged as a result of this study. Firstly, due to the different clinical forms of presentation at ED associated with SC use and the range of intoxications that cannot be diagnosed, advanced laboratory tests are required, in addition to routine tests for the determination of SC. Secondly, those diagnosed as having taken SC were also determined to have used it concurrently with substances that have a high potential for addiction, such as amphetamines and quetiapine. Thirdly, in regard to examples of cases presented in the literature, anti-psychotics, fluid hydration, and anxiolytics can be used as treatment options for those diagnosed with SC use