Flow past an elliptic cylinder

AbstractA theoretical investigation of the unsteady two-dimensional flow of a viscous, incompressible fluid normal to a thin elliptic cylinder is described. The cylinder, which is started impulsively from rest in an open field, continues to move with uniform velocity for the remainder of the problem. Using a vorticity-streamfunction formulation of the full Navier-Stokes equations, transformation techniques are employed to find the initial flow. Strategies which employ boundary layer theory and series expansions of the flow variables to find flow solutions for small values of time are outlined

Viscous Fluid Flow Past An Impulsively-started Flat Plate

The problem of studying the behaviour of a fluid moving past a body constitutes a classical area of research in fluid dynamics. In this work, the unsteady and steady flow of a viscous, incompressible fluid past a flat plate, situated normal to the flow and started impulsively from rest, is considered. The Navier-Stokes equations and the continuity equation are formulated in terms of the streamfunction and the vorticity.;For the case of flow in an unbounded region, transformational and perturbational techniques are used to obtain exact solutions for initial and small time values. These solutions are valid for large values of the Reynolds numbers.;Finite-differencing techniques are employed in solving the problem of channel-contained steady flow of a viscous, incompressible fluid past an impulsively-started flat plate. These solutions were found to be in close agreement with experimental work done on the same problem. Calculations were carried out for small values of the Reynolds number, ranging from 5 to 20

Empowering through Light: Women and Solar Home Systems in Rural Bihar, India

In rural India, women in poor households spend a large part of their day performing basic tasks such as collecting fuel wood or kerosene, which keeps them away from employment or education opportunities and makes their lives more difficult. Access to electricity is therefore increasingly regarded as a means to improve their status in society. Although a large number of small-scale and community-based off-grid renewable energy projects are in place to provide access to electricity with a women-centric approach, research on the benefits to women has been largely anecdotal. A review of the evidence for the impact of rural electrification on women’s lives concluded that electricity access has a positive effect on women’s practical needs by reducing drudgery and providing better health, time-savings and income generation

Prediction of disease severity in patients with febrile illnesses in resource-limited settings

Febrile illnesses present unique challenges for health systems with scarce resources. Large volumes of mostly self-limiting diseases accompanied by high case-fatality rates for the small proportion of serious infections mean that risk stratification tools must have high sensitivities and/or specificities according to their proposed contexts of use. Unfortunately, accuracy and reliability of existing tools are sub-optimal and they are often impractical for deployment in resource-limited settings. This thesis explores the development and application of prediction tools for the management of febrile illnesses across a range of resource-constrained settings in South and Southeast Asia. It aims to combine the best prediction model science with a pragmatic field-based reality to address locally-important health issues. Recognising that evaluation of prediction tools should be set in their intended contexts of use, each analysis is framed in a particular clinical use-case, yet draws upon approaches to allow exploration of the generalisability of the findings. Using a variety of research methodologies, this thesis identifies prognostic factors amongst febrile children presenting to different levels of the health system, and uses these data to externally validate existing severity scores and develop new clinical prediction models suitable for resource-limited settings. Prospective work evaluates the relative contributions of clinical and biomarker-based approaches for the referral of children with respiratory infections from a resource-limited community setting on the Thailand-Myanmar border, whilst retrospective work develops a prognostic model for critically ill children on admission to a paediatric intensive care unit in northern Cambodia. Finally, in response to the arrival of the SARS-CoV-2 pandemic, this thesis reports the development and external validation of prognostic models at two sites in India to support the safe outpatient management of patients presenting with moderate Covid-19. Important challenges and potential solutions to developing prediction tools in resource-limited settings are discussed, including application of the classical prediction paradigm to the assessment of disease severity, comparative analyses of the clinical utility of different models, and the differential importance of various predictors for identifying both patients who are sick at the time of clinical assessment and those whose illnesses will progress later in their disease course

Spatial Boundaries, Abounding Spaces

Colonial expansion and spatial grammar in French-language works from different historical and national contexts Colonialism advanced its project of territorial expansion by changing the very meaning of borders and space. The colonial project scripted a unipolar spatial discourse that saw the colonies as an extension of European borders. In his monograph, Mohit Chandna engages with narrations of spatial conflicts in French and Francophone literature and film from the nineteenth to the early twenty-first century. In literary works by Jules Verne, Ananda Devi, and Patrick Chamoiseau, and film by Michael Haneke, Chandna analyzes the depiction of ever-changing borders and spatial grammar within the colonial project. In so doing, he also examines the ongoing resistance to the spatial legacies of colonial practices that act as omnipresent enforcers of colonial borders. Literature and film become sites that register colonial spatial paradigms and advance competing narratives that fracture the dominance of these borders. Through its analyses Spatial Boundaries, Abounding Spaces shows that colonialism is not a finished project relegated to our past. Colonialism is present in the here and now, and exercises its power through the borders that define us

Disruption of RAGE signaling prevents sympathetic neuron malfunction in high glucose conditions

Diabetes, which is characterized by elevated plasma glucose, can have a devastating effect on peripheral nerves frequently leading to the clinical symptoms of neuropathy. Diabetic autonomic neuropathy (DAN) results from damage to autonomic nerves, and the most troubling forms of DAN often lead to cardiovascular abnormalities and premature death. Despite the prevalence of DAN and the impact to quality and life expectancy, the precise mechanisms underlying these pathologies are poorly understood. Recently, a new model for the onset of DAN was proposed where hyperglycemia-induced oxidative stress inactivates nicotinic acetylcholine receptors (nAChRs), the main receptor driving autonomic synaptic transmission at sympathetic ganglia. This inactivation leads to the depression of synaptic transmission, and consequently triggers the onset of autonomic neuropathy in diabetic mice. However, the source and pathways contributing to the elevation of reactive oxygen species (ROS) and oxidative stress remained unclear. In recent years it has been shown that the accelerated formation of advanced glycation end products (AGEs) and activation of their receptor (RAGE) in diabetes play a major role in the induction of oxidative stress in sensory nerve damage. Thus we hypothesized that the activation and up-regulation of RAGE during high glucose conditions is a major source of ROS production in sympathetic neurons leading to the inactivation of nAChRs and autonomic malfunction. In this thesis we show for the first time that RAGE is expressed in cultured sympathetic neurons and is also up-regulated during high glucose conditions. Our results further demonstrate that direct RAGE activation by its natural ligands leads to an increase in cytoplasmic ROS which in turn induces the inactivation of nAChRs in sympathetic neurons. We also report that high glucose-induced ROS generation and subsequent inactivation of nAChRs is prevented in sympathetic neurons from RAGE knock-out mice. The results of this dissertation suggest RAGE to be a pivotal source of ROS production leading to the functional deficits observed in sympathetic neurons during high glucose conditions

Statistical Properties of the Estimator of the Rotary Coefficient

Accepted versio

eCodicology: The Computer and the Mediaeval Library

Through digitisation a large amount of mediaeval manuscript collection became publicly available, but the resources in time and human attention have not grown in proportion of digitised sources. Therefore, the question arises whether the computer can help to evaluate larger amounts of material like this. The project eCodicology has focused its research on the detection and measuring of the different layout features by using methods of pattern recognition for further analyses. The present paper gives insights into the developed software, SWATI – the Software Workflow for the Automatic Tagging of Images, and CodiVis, a visualisation framework for high-dimensional data sets, and how it can help the codicologist to explore the massive amount of heterogeneous datasets. The paper also focusses the various challenges, such as uncertain data due to irregularities and missing information in the manuscript’s catalogues, as well as the accuracy of the image processing results

When your eye patient is a child

In this issue of the journal, we address the eye health needs of young children, focusing on those aged less than six years old. All of you who have tried to examine or measure the visual acuity of young children will know that this can be very challenging and difficult; it can be very tempting to give up and send the child home, particularly if the clinic is busy. We hope that, after reading this edition of the journal and putting into practice some of the practical suggestions, you will feel more confident in managing young children. Also, if referral is needed, you will have a better idea of the degree of urgency required and how this should be communicated to parents