Analysis of sand asphalt mixtures

The objective or this investigation was to determine the optimum percent of asphalt which should be added to the sand asphalt mixture. Also the effects of filler on the properties or the sand-asphalt mixture were evaluated. The variables in this study were mineral filler, asphalt cement, and asphalt content. The sand used in this study was sub-rounded, and uniformly graded. The asphalt was asphalt cement with two different penetrations, one of 85-100 penetration grade and the other of 120-150 penetration grade. Three different groups of mixtures of sand-asphalt were prepared. The first group consisted of adding 85-100 penetration asphalt to a mixture of sand and filler. The second group consisted of adding 85-100 penetration asphalt to sand only. The third group consisted of adding 120-150 penetration asphalt to sand. All mixes were prepared by the Harvard Compaction machine and tested in an unconfined compression machine. The physical properties analyzed were compressive strengths, unit weight and air voids in the mineral aggregate. It was found that an asphalt content of four percent appears to be an optimum percentage for the three groups of mixtures tested. It was found also that filler increased the desirable properties or sand-asphalt mixture --Abstract, page ii

Transpiration cooling of a porous plate

Transpiration cooling has long been known as an effective way of removing heat from porous materials. This thesis is a new approach to one of the problems of transpiration cooling in the steady state. The specific problem considered here is that of a uniform porous plate through which a liquid is forced. This liquid vaporizes at a short distance from the surface through which it is forced and leaves the porous plate at the other surface which is exposed to hot gases. It also protects the hot surface by forming an insulating layer between that surface and the hot gases. Pumping liquid rather than vapor is particularly efficient because of its absorption of heat in evaporation. It is assumed that there exists a finite temperature difference between the solid particles and the coolant in the adjacent pores. The solution of the problem is illustrated by an example employing high alumina refractory plate having a thickness slightly more than 0.1 ft. Cooling is provided by a uniform flow of water in a direction counter to the flow of heat, while one surface of the plate was heated by convection heat transfer by a hot gas. The temperature of the coolant leaving the plate is determined by the amount of heat flux, coolant mass rate of flow and the specific heat of the coolant. The temperature distribution in the coolant was calculated by solving the equations derived in this thesis on the Missouri School of Mines and Metallurgy LGP-30 Royal McBee Digital Computer. The result of this investigation proves that transpiration cooling is an effective way of cooling and that the temperature drop of the coolant near the hot face is larger than that near the other end allowing the use of relatively thin plates for transpiration cooling. It was also shown that values of film coefficient of 2 or greater than 2 give discontinuities in the temperature distribution curve of the coolant within the porous plate and that low thermal conductivities of the solid material give better effectiveness to this method of cooling --Abstract, pages 2-3

Macalester at Home and Abroad, Reel 2

Dr. Yahya Armajani interviewed Barkley Acheson Professor of International Studies Fayez Sayegh about the effects of change in the Middle East. Reel #13, run time 28:5

Fungal infections in renal transplant patients

Organ transplantation has always been considered to be the standard therapeutic interventions in patients with end-stage organ failure. In 2008, more than 29,000 organ transplants were performed in US. Survival rates among transplant recipients have greatly improved due to better understanding of transplant biology and more effective immunosuppressive agents. After transplant, the extent of the immune response is influenced by the amount of interleukin 2 (IL-2) being produced by the T-helper cells. Transplant immunosuppressive therapy primarily targets T cell-mediated graft rejection. Calcineurin inhibitor, which includes cyclosporine, pimecrolimus and tacrolimus, impairs calcineurin-induced up-regulation of IL-2 expression, resulting in increased susceptibility to invasive fungal diseases. This immunosuppressive state allows infectious complication, leading to a high mortality rate. Currently, overall mortality due to invasive fungal infections (IFIs) in solid organ transplant recipients ranges between 25% and 80%. The risk of IFI following renal transplant is associated with the dosage of immunosuppressive agents given, environmental factors and post-transplant duration. Most fungal infections occur in the first 6 months after transplant because of the use of numerous immunosuppressors. Candida spp. and Cryptococcus spp. are the yeasts most frequently isolated, while most frequent filamentous fungi (molds) isolated are Aspergillus spp. The symptoms of systemic fungal infections are non-specific and early detection of fungal infections and proper therapy are important in improving survival and reducing mortality. This article will provide an insight on the risk factors and clinical presentation, compare variation in treatment of IFIs in renal transplant patients, and evaluate the role of prophylactic therapy in this group of patients. We also report the course and management of two renal transplant recipients admitted to Staten Island University Hospital, both of whom developed pulmonary complications secondary to Aspergillus infection

Effect of a pedometer-based walking challenge on increasing physical activity levels amongst hospital workers

Background: More than 50% of Qatari adults are physically inactive. The workplace is an excellent environment to implement cost-effective, efficient behavioural physical activity (PA) interventions to increase PA. This study evaluated whether a pedometer-based walking challenge would increase PA levels amongst hospital workers. Methods: A pedometer-based workplace walking intervention was implemented in April-August 2017. Amongst 800 recruited full-Time hospital workers, a cross-sectional sample of 212 workers completed the online questionnaires Quality of Life Questionnaire, International Physical Activity Questionnaire (IPAQ), and Workforce Sitting Questionnaire. A sub-sample of participants (n = 54) wore a pedometer for 3 months. They recorded their daily step count through an online web platform linked to the pedometer. Another cross-sectional sample (n = 194) in the same target population completed online questionnaires at post intervention. Results: The IPAQ assessed physical activity at post-intervention was higher compared to pre-intervention. In a sub-sample (n = 54) that provided pedometer data, workers' step count during intervention was significantly higher (9270) from pre-intervention (7890) (p = 0.048). Conclusions: Although self-reported PA was higher post-intervention, the subsample showed objectively assessed physical activity did not exceed the threshold recommended for optimal health. Therefore, encouraging participation and maintaining motivation amongst workers in a work-based PA programme is challenging. - 2019 The Author(s).The publication of this article was funded by the Qatar National Library. We would like to acknowledge, Mr. Manaf Kamil, Application Architect in assisting us to extract pedometer data for analysis. Also we would like to thank Mr. Christopher Mengelt, Director of planning and performance for his assistance in dissemination of e-surveys. Finally, we are grateful to Dr. Nathan Riding for English language editing

Justice in a Non-Ideal World

This doctoral thesis, titled Justice in a Non-Ideal World, explores the methodology and the content of a non-ideal theory of justice. It puts forward a methodology for theorising about politics according to which ideal theory does not have analytical primacy over non-ideal theory. Non-ideal theory is not a matter of implementing ideal principles, but rather a field of inquiry that seeks balance between moral values and real world considerations that constrain the realisation of justice. I argue that although there is value in ideal theorising, the specific task of guiding political action is better carried by non-ideal theory. This thesis highlighted the contribution of a non-ideal approach to our theorising about politics and explored the action guiding potential of non-ideal theory by identifying its defining features. This contribution is exemplified in the contexts of tax competition, climate justice and carbon pricing. This thesis explores ways through which the non-ideal theorist contributes to the normative weightlifting of political philosophy by gathering knowledge from other disciplines (in particular social sciences, economics, climate sciences) without presupposing ideal theory. I argue that non-ideal theorising provides not only non- normative supplementations to political theory, in terms of elements that counted as empirical and social scientific input, but also some of its core normative components. The problem this thesis sets out to fix is centrally a problem with the normative incompleteness of ideal theory. I found that non-ideal theory provides valuable insights to formulate an action guiding political theory – especially with regard to compliance, feasibility, fact-sensitivity and path dependence – in order to address issues such as tax competition, climate justice and carbon pricing, which require the collaboration of researchers across a range of disciplines

Treatment of Hydrothermal-Liquefaction Wastewater with Crossflow UF for Oil and Particle Removal

This study aims to evaluate the application of ceramic ultrafiltration membranes in the crossflow mode for the separation of particles and oil in water emulsions (free oil droplets and micelles) from hydrothermal-liquefaction wastewater (HTL-WW) from the hydrothermal liquefaction of municipal sewage sludge. The experiments were carried out using one-channel TiO$_{2}$ membranes with pore sizes of 30, 10 and 5 nm. The results showed that the highest stable permeability could be achieved with a membrane-pore size of 10 nm, which experienced less fouling, especially through pore blockage, in comparison to the two other pore sizes. Instead of observing an increase in the permeability, the application of a higher feed temperature as well as backwash cycles led to a clear increase in irreversible fouling due to the presence of surfactants in the HTL-WW. Among several physical and chemical cleaning methods, alkaline cleaning at pH 12 proved to be the most efficient in removing fouling and maintaining stable performance on a long-term basis. Ceramic-membrane ultrafiltration can be considered as an adequate first-stage treatment of real HTL wastewater

An Overlapping Case of Lupus Nephritis and IgG4-Related Kidney Disease

We report a case of a 71-year-old Filipino female who was admitted to the hospital for abdominal pain, vomiting and diarrhea of 8 days duration. The patient was found to have marked acute kidney injury (AKI), which required hemodialysis in the next 3 days. Extensive workup revealed hematuria, subnephrotic range proteinuria, elevated anti-nuclear antibody (ANA) and elevated total immunoglobulin G (IgG) levels, with normal IgG4 and anti-dsDNA levels. On kidney biopsy, mild membranous glomerulonephritis was found, along with autoimmune tubulointerstitial nephritis (TIN) with a full-house pattern of immune deposits. These findings were suggestive of lupus interstitial nephritis. However, IgG4+ plasma cells were detected in the interstitium by immunostaining, favoring a diagnosis of IgG4-related kidney disease (IgG4-RKD). Our case highlights the difficulty in differentiating lupus nephritis (LN) from IgG4-RKD in some patients, raising the suspicion that these two entities can co-exist

Suppressing scratch-induced brittle fracture in silicon by geometric design modification of the abrasive grits

The overarching goal of this research was to investigate the application of spherically shaped abrasive particles in achieving ductile-mode cutting. Scratching experiments were carried out to assess the differences between arbitrarily and spherically shaped diamond and tungsten carbide (WC) grits in inducing brittle fracture or ductile plasticity in single-crystal silicon. It was observed that the arbitrarily shaped particles produce brittle fracture in contrast to the spherically shaped grits. The sharp edges and corners of grits result in high tensile stress-concentrated regions causing cracking and spalling. Contrary to this, spherically shaped WC particles induce uniform cutting pressure, which suppresses the extent of the brittle fracture and the mode of material removal was completely dominated by ductile-cutting until a threshold load for ductile-to-brittle transition (the first cracks appearance). These observations are expected to provide a suitable pathway in making the Diamond Wire Sawing machining operations more robust by providing a control on brittle damage