Background. The growing population of migrants (including sub-Saharan Africans) in the United Kingdom poses challenges to British general practice. First, migrants tend to seek health care at times of crisis rather than for preventive measures. This is despite being at increased risk of certain chronic conditions compared with the indigenous population. For sub-Saharan Africans this includes hypertension-related diseases and some cancers. Little has been published about Africans’ awareness of this risk or their knowledge of associated causative factors. Second, discordant health beliefs and healthcare expectations between migrants and doctors in the UK have been found to undermine trust during consultations with general practitioners and to lead to poor patient satisfaction. Little is known about the health behaviours of African migrants whose expectations are not met by primary care in the UK. A related area where health beliefs and practices differ between African migrants and their GPs is in the use of traditional medicines. A final challenge lies in considering the wider issues that GPs must address when consulting with migrant patients, including time pressures, organisational factors and the complex nature of problems presented by migrant patients. These issues are the focus of this study. Aims. To examine African migrants’ perceptions of chronic disease and their experience of seeking primary health care in the UK. To explore the impact upon GPs of caring for migrants. Objectives. To explore: 1) perceptions of chronic disease risk facing African migrants and their underlying explanatory models; 2) experiences of consultations about antibiotic prescriptions; 3) traditional African medicine use in the UK; and (4) to consider the effect of workload and work patterns on GP consultations with migrants. Design. In-depth interviews were conducted with 19 Africans from French- or Swahili- speaking countries, one African key informant and 13 GPs working with migrants. African participant recruitment was from community organisations and GPs were approached via an informal network of doctors. Interviews were transcribed and ten were translated by the principal investigator (three Swahili and seven French). Data analysis was undertaken following the approach of applied thematic analysis using the Nvivo software package. Data collection and analyses were underpinned by the following theoretical frameworks: Kleinman’s explanatory models of illness and of cultural health care systems and Lipsky’s street-level bureaucracy. Results. Narratives suggested low awareness of chronic disease risk amongst Africans. Infectious diseases were considered the dominant health threat for African migrants, mainly HIV but also tuberculosis and ‘flu’. Chronic diseases were sometimes described by Africans as contagious. Explanatory models of chronic disease included bodily/dietary imbalance, stress/exertion, heredity/predisposition and food contamination. Cancer was feared but not considered a major threat. Cancer was considered more common in Europe than in Africa and was attributed by Africans to chemical contamination from fertilizers, food preservatives and industrial pollution. Evidence cited for these chemicals was rapid livestock/vegetable production, large size of farmed products (e.g. fish), softness of meat and flavourless food. Chemicals were reported to circulate silently inside the body and cancer to develop in the part where they deposit, sometimes years later. Africans’ belief in infective explanations of disease extended to minor illnesses and was manifested in an expectation of antibiotics from GPs for problems such as a sore throat. This arose from participants’ experience in Africa, witnessing life-threatening infectious diseases and experience of unregulated access to antibiotics. Africans described various alternative measures to fulfil their unmet expectations, including approaching other National Health Service doctors, importing medication, and using private healthcare services in London, francophone Europe and east Africa. A further option was the use of traditional African medicine, reported by one quarter of African participants. Traditional African herbal medicine use was based upon a perception of its purity and natural origin in African soil and a deep belief in its efficacy. Consulting traditional African healers in the UK was reported to be undertaken in secret. Some GPs and Africans described consultations in terms of pressure, processing and conflict. Migrants were reported to present with complex health problems that were frequently compounded by language barriers. GPs described a need to remain in control of consultations and this included some use of personal discretion to render their tasks easier to complete. The most common example was accepting patients’ family and friends as informal interpreters – a choice that ran contrary to formal policy of only using professional interpreters. Burnout was reported to be one consequence of excessive workload for patient-centred GPs working with vulnerable groups like asylum seekers. Conclusions. There is a need to improve health literacy amongst African migrants in order to promote preventive behaviours for chronic disease and alternatives to antibiotics for minor illnesses. As part of this, further research is required into the use and properties of traditional African medicine. Interventions should be built upon participants’ existing knowledge of disease causation, their self-reliance in the pursuit of a healthy lifestyle and desire to retain cultural practices. One challenge to improving migrant health lies in the service dilemmas facing GPs, including excessive workload, the complex nature of migrants’ presenting problems and professional dilemmas. GPs who act as advocates for vulnerable migrant patients may be at increased risk of burnout and greater consideration should be given to providing them with appropriate support.

This thesis deals with enhancing the performance of Fuzzy Logic (FL) based PI controllers for High Voltage Direct Current Transmission Systems (HVDC) by optimizing the key parameters i.e. membership functions (MFs) and fuzzy rule base in the controllers design. In the first part of the thesis, an adaptive Fuzzy PI controller is designed and the effect of various MF shapes, widths and distribution on the performance of a FL controlled HVDC system under different system conditions is studied with the aim of selecting a MF which minimizes the total control error. Simulated results show that the shape, width and distribution of a MF influences the performance of the FL controller and concludes that nonlinear MFs (i.e. Gaussian) offer a more better choice than linear (i.e. Triangular) MFs as the former provides a smoother transition at the switching points and thus propose a better controller. In the second part of the thesis, a Neuro-Fuzzy (NF) controller to update the fuzzy rule base with changing system conditions is proposed, which in turn adjusts the PI gains of a conventional PI controller. Results from simulations illustrate the potential of the proposed control scheme as the NF controller successfully adapts to different system conditions and is able to minimize the total current error. / UOIT

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Epidemiological studies indicate that there is an inverse relationship between consumption of cruciferous vegetables and risk of cancer. As a result there is much interest in understanding the anticancer potential not only of cruciferous vegetables themselves but also of the key phytochemicals contained in them. This project focuses on the potential anticancer properties of watercress, a cruciferous vegetable which is cultivated around the world and eaten raw as a salad vegetable as well as in cooked dishes. Watercress is the most abundant source of gluconasturtiin, a precursor to the phytochemical phenethyl isothiocyanate (PEITC), and is also a rich source of indole-3- carbinol (13C) and quercetin. This project addressed the hypothesis that the in vitro anticancer activity of watercress can be enhanced by altering the growth environment. To investigate this it was necessary to develop assays that can be used to assess the in vitro anticancer activity of watercress-derived compounds, to explore the mechanisms by which PEITC exhibits its anticancer effects, and to determine potential effects of altered growth conditions on in vitro anticancer properties. The activity of watercress-derived phytochemicals was analysed in a series of in vitro assays. Based on these results, inhibition of MCF7 cell growth and activation of Nrf2-dependent transcription were selected as potential assays for subsequent analysis of watercress extracts. Mechanistic studies demonstrated that PEITC inhibited the transcriptional activity of hypoxia inducible factor (HIF), a key positive regulator of angiogenesis in malignant cells. Inhibition of HIF function was associated with inhibition of mammalian target of rapamycin complex 1 (mTORC1) activity and decreased HIF1 a mRNA translation, and was dependent on the presence of the mTORC1 regulator, tuberous sclerosis complex 2 (TSC2). I also demonstrated that, in addition to effects on HIF1 a mRNA translation, PEITC inhibited general protein synthesis and modulated two other key regulators of translation, eukaryotic initiation factor 2 (eIF2) and eukaryotic elongation factor 2 (eEF2). In proof-of-principle experiments, I demonstrated that growth inhibition and Nrf2 activation assays were suitable for the analysis of crude watercress extracts and that a natural variety of "red" watercress displayed approximately 10-fold more potent in vitro anticancer activity than standard, commercial "green" watercress. However, in a series of field trials, modulation of time of harvest, water availability or sulfur fertilisation did not alter the in vitro effects of watercress extracts in growth inhibition/Nrf2 activation assays. In conclusion, this study suggests that, rather than altering environmental factors, selective breeding might be a better approach to increase the in vitro anticancer activity of watercress. Moreover, my findings have increased our understanding of the mechanisms underlying the anticancer activity of PEITC, uncovering a novel role for PEITC in inhibiting HIF1 a and total protein synthesis, and identifying several key regulators of these processes that are modulated by PEITC

This document describes design of regulator of gripping force for robotic gripper Schunk PG70. In the first part of this document there is described electircal connection, interconnection with control systém and testing of robotic gripper. The second part of document desribes design of software regulator of gripping force and material recognition with robotic gripper. Document also describes experiments with implementet regulator and sumarizes real measured values of atributes of the regulator.

Background: Type 2 Diabetes (T2D) is growing in prevalence worldwide over the last century. T2D incidence is linked to numerous complications, increased risk of heart disease, and oncology outcomes. This highlights the importance of preventive measures for T2D, wherein genetic predisposition can serve as an early warning sign. The role of rare variants (RVs) in T2D pathogenesis has not been adequately explored due to study size limitations, therefore we hypothesized that new associations could be found using publicly available data repositories. Methods: Significant RV gene burden for T2D risk was discovered using exome sequences obtained from the United Kingdom Biobank (UKB) (n=162,215), then tested for replication in the Korean Association Resource project (n=973), the Metabolic Syndrome in Men Study (n=969), the San Antonio Mexican American Family Studies (n=309), and a pooled meta-analysis of the latter three cohorts. RV gene burden was reassessed in secondary analyses using T2D cases from each cohort and summary level data from the Genome Aggregation Database (GnomAD) (n=125,748). Results: UKB exome wide significant associations were found in GCK (OR=2.44, p=8.91×10-11) and PAM (OR=1.32, p=1.39×10-6), and suggestive associations (p<0.001) were found in 33 additional genes. Replication was limited in KARE, METSIM, SAMAFS and in the secondary analyses with GnomAD because of limited sample sizes and miscalibration with the external control, respectively. Follow-up analyses include exploration of RV gene burden in additional diabetes subtypes, evaluation of clinical features between RV carriers and non-carriers, comparing the ability to predict T2D with rare variant, polygenic, and phenotypic risk scores. Methodological improvements include the incorporation of robust analytic tools and increasing access to a greater diversity and number of samples. Conclusion: Publicly available exome sequencing data has identified genes where RV burden affects T2D pathogenesis and risk. The study of rare genetic variation in diabetes is just beginning. / Thesis / Master of Science (MSc)

Covid19 hit the world’s financial markets by surprise in March 2020 and ensuing volatility marked an end to the prior low-volatility environment. This Black Swan engendered numerous publications establishing how the equity market responded to the exogenous shock. However, there is no applicable comparison to Nasdaq100 regarding how models perform during extreme conditions such as ante, amid and post Covid19. Furthermore, goodness of fit together with forecasting accuracy are further examined in the light of new intra-day data from Oxford Man Institute covering this time-period. This thesis presents a comparison of volatility models incorporating economic intuition, sentiment, historical values of volatility and stochastics. By exploiting intra-day at 5 min interval the trade-off between noise and loss of valuable information effectively kept at a minimum yielding considerable robustness to the thesis’ result. Linear ARCH-models, Implied Volatility and HARRV applied with the addition of several different combinations of hold-out periods enable multiple vantagepoints for evaluation. This thesis finds HARRV’s series of one-step ahead prediction of future conditional volatility to be superior throughout all hold-out periods. I am able to present empirical evidence supporting the idea that HARRV’s additive cascades of volatility is superior to sentiment-driven implied volatility and ARCH-models pertaining to Nasdaq100.

<p>Due to the advancements in computing power and the availability of high-frequency data, the analyses of the high frequency stock data and market microstructure has become more and more important in econometrics. In the high frequency data setting, volatility is a very important indicator on the movement of stock prices and measure of risk. It is a key input in pricing of assets, portfolio reallocation, and risk management. In this thesis, we use the Heterogeneous Autoregressive model of realized volatility, combined with Bayesian inference as well as Markov chain Monte Carlo method’s to estimate the innovation density of the daily realized volatility. A Dirichlet process is used as the prior in a countably infinite mixture model. The semi-parametric model provides a robust alternative to the models used in the literature. I find evidence of thick tails in the density of innovations to log-realized volatility.</p> / Master of Science (MSc)