Hypersonic boundary layers in strong pressure gradients

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The male predominance in oesophageal adenocarcinoma and the role of sex hormones

Oesophageal adenocarcinoma is a subtype of oesophageal cancer with rapidly rising incidence over the last decades. This rise in incidence is strongest in western countries and more among men than in women, with a male predominance of up to 9:1 in some countries. Despite several risk factors for oesophageal adenocarcinoma being uncovered, the male predominance is largely unexplained. The aim of this thesis was to investigate the aetiology behind oesophageal adenocarcinoma and its male predominance, with focus on sex hormones. Study I was a systematic review and meta-analysis investigating the association between obesity-related serum biomarkers and the risk of oesophageal adenocarcinoma and its precursor condition, Barrett's oesophagus. A literature search in MEDLINE and EMBASE was conducted, covering studies published until October 2018. Out of 7,641 studies, 19 were included (12 cross-sectional, 2 nested case-control, and 5 cohort studies). Random-effects meta-analysis pooled the odds ratios comparing the highest and lowest categories of biomarker levels. No associations were found for adiponectin, ghrelin, insulin-like growth factor 1, insulin-like growth factor-binding protein 3, triglycerides, Interleukin 8, or tumour necrosis factor alpha. Higher levels of leptin, glucose, insulin, C-reactive protein, interleukin 6, and soluble tumour necrosis factor receptor 2 were potentially linked with an increased risk of oesophageal adenocarcinoma or Barrett's oesophagus Study II was a nested case-control study in 1972-2016 examining how circulating sex hormone levels influence the risk of oesophageal adenocarcinoma. The source population was the Norwegian Janus Serum Bank Cohort, and this study included 244 male patients with oesophageal adenocarcinoma and 244 male age-matched control participants. Associations between prediagnostic circulating levels of 12 sex hormones and risk of oesophageal adenocarcinoma were analysed using conditional logistic regression. Associations were observed for testosterone, testosterone:oestradiol ratio and luteinizing hormone, but not for sex hormone–binding globulin, dehydroepiandrosterone sulfate, follicle-stimulating hormone, prolactin, 17-OH progesterone, progesterone, androstenedione, or free testosterone index. In addition, a random-effects meta-analysis, combining the results of this study with a similar prospective study, revealed an inverse association between testosterone levels and the risk of oesophageal adenocarcinoma (pooled OR = 0.60, 95% CI 0.38–0.97). No associations were found for androstenedione, sex hormone–binding globulin, oestradiol, or testosterone:oestradiol ratio in the meta-analysis. Study III was a nationwide Swedish population-based cohort study between 2005 and 2018 comparing the risk of oesophageal and gastric tumours among 191,156 users and 1,911,560 (10 times as many) non-users of 5α-reductase inhibitors (5-ARIs). Multivariable Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, calendar year, smoking, non-steroidal anti-inflammatory drugs/aspirin use, and statins use. Further adjustments were made depending on the tumour analysed. Users of 5-ARIs had a substantially decreased risk of developing oesophageal or cardia adenocarcinoma among those obese or diabetic (adjusted HR 0.55, 95% CI 0.39-0.80), and a decreased risk of oesophageal squamous cell carcinoma (adjusted HR 0.49, 95% CI 0.37-0.65). Study IV was a nationwide Swedish population-based cohort study hypothesizing that the use of 5-ARIs improves survival in patients with oesophago-gastric cancer. The study included men who underwent surgery for oesophageal or gastric cancer between 2006 and 2015, with follow-up until the end of 2020. Out of the 1769 patients diagnosed with oesophago-gastric cancer, 64 (3.6%) had a history of using 5-ARIs. Multivariable Cox regression estimated HRs for associations between 5-ARIs use and 5-year all-cause mortality (main outcome) and 5-year disease-specific mortality (secondary outcome) with adjustment for confounders. Compared to non-users, users of 5-ARIs were not at any decreased risk of 5-year all-cause mortality (adjusted HR 1.13, 95% CI 0.79-1.63) or 5-year disease-specific mortality (adjusted HR 1.10, 95% CI 0.79-1.52) in gastro-oesophageal cancer

Design of a Model Rocket Flight Logging System and In-Air Deployable Rover

The goal of the project laid out in this paper is to develop a model rocket range and altitude tracking system and a payload for said rocket which conducts an experiment of some scientific merit. The requirements for the project are defined by the rules of an international model rocket design and build competition for undergraduate and graduate students. This paper presents a design to accomplish the specified goals to the standards of the competition rule set, for use by the Union College Rocket Team at the competition. First, an off-the-shelf flight computer is purchased to implement the range and altitude tracking requirements. The selected component is researched thoroughly and tested to ensure it performs as expected. Next, a design is developed for a scientific payload known as the Habitability Assessing Research Vehicle, or HARVe for short. HARVe is a rover which is stored within a model rocket and, depending on the rocket’s capabilities, can be deployed while in flight or on the ground after the rocket has landed. Once it is free of the rocket and on the ground, it will roam the landing zone and assess the habitability of the area through imaging and air quality tests. As of the submission of this report, HARVe has been prototyped to complete a number of its final functions, yet testing and further implementation of these abilities continues as the design is iteratively improved

Legal Anarchism: Does Existence Need to Be Regulated by the State

This thesis asks does existence need to be regulated by the State? The answer relies on legal anarchism, an interdisciplinary, particularly criminal law and philosophy, and unconventional research project based on multiple methodologies with a specific language. It critically analyzes and consequently rejects State law because of its unjustified and unnecessary nature founded on unlimited violence and white-collar crime (Chapters 1-4), on the one hand, and suggests some alternatives to the Governmental legal system founded on agreement and peace (Chapter 5), on the other hand. It furthermore takes into account the elements of time and space, which means the ecological, local, national, regional, and international aspects of the legal system, in its analysis, critiques, and models

The Origins of Common Identity: Division, Homogenization Policies and Identity Formation in Alsace-Lorraine

We exploit the fact that disagreements in the German leadership after the Franco-Prussian War in 1870 led to a quasi-exogenous division of Alsace and Lorraine to provide rare evidence of group identity formation within historically homogeneous regions. In line with the rejection-identification hypothesis, people in the treated area which experienced a change in nation-status and were exposed to repressive homogenization policies express a stronger regional identity and support more regional autonomy today. On average, subjects with a stronger regional also express a stronger European identity, which we exploit in a regression discontinuity design at the municipal level to reveal whether these identity differences are causal. We find that support for the European Union is significantly stronger in two crucial referenda, a result that is robust across different specifications and bandwidths, and not driven by language differences, large agglomerations or distance to foreign countries. The effect seems to be the strongest for the first two age cohorts after World War II and diminishes for later generations

Explaining the model of comprehensive waste management in urban and rural areas and intermediate spaces (Case study: Khorasan Razavi province)

One of the main topics of sustainable development is environmental issues. Waste management is one of the most important environmental programs in the world. Today, statesmen have come to the conclusion that in order to achieve an ideal and sustainable society, it is necessary to pay attention to waste management. This study was conducted to identify the current status of waste management in Khorasan Razavi province and provide an optimal management model. This is a descriptive-analytical study. The sample population includes all cities and villages of Khorasan Razavi province. The sample size in cities with waste management organization was in full and in other cities and districts using random sampling method using Cochran's formula. The results were classified and analyzed using SPSS, Excel and GIS software. Data collection tools were library resources, field resources including interviews with experts, managers and professors of technology. Preparation and completion of questionnaires from urban and rural areas is the preparation of checklists and field visits. Based on the SWOT model strategy and internal and external environment analysis, the most important strength is the reduction of entrepreneurship in the implementation of waste management activities and the lack of a comprehensive plan for waste management is the most important weakness. In assessing the external environment, the existence of industries and markets for the consumption of recycled materials in the province and the region is the most important opportunity and the existence of economic crises in urban and rural communities and industrial areas in the region is the most important threat. The results of the study indicate the need to improve the framework and infrastructure of waste management in the province and the development of laws and detailed monitoring systems to implement the findings and scientific and practical experiences of other countries to achieve economic, social and environmental goals

Improving thermostability of tryptophan 2-monooxygenase by semi-rational engineering

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