50 research outputs found
A Scalarizing One-Stage Algorithm for Efficient Multi-Objective Optimization
No full textA novel kriging-assisted algorithm is proposed for computationally expensive multi-objective optimization problems, such as those which arise in electromagnetic design. The algorithm combines the multiple objectives into a single objective, which it then optimizes using a one-stage method from singleobjective optimization. Its efficiency is demonstrated by comparison to a random search on a difficult test function
Birmingham News sleeve BN0029827
No full textR. R. Hawes murder case / Copies / Henderson / May, age 11 / Irene, [age] 8 / Emma Hawes / Richard Hawe
Evidence of admixture from haplotyping in an epidemiological study of UK Caucasian males: implications for association analyses
No full textObjective: Cohort and case-control genetic association studies offer the greatest power to detect small genotypic influences on disease phenotypes, relative to family-based designs. However, genetic subdivisions could confound studies involving unrelated individuals, but the topic has been little investigated. We examined geographical and interallelic association of SNP and microsatellite haplotypes of the Y chromosome, of regions of chromosome 11, and of autosomal SNP genotypes relevant to cardiovascular risk traits in a UK-wide epidemiological survey. Results: We show evidence (p = 0.00001) of the Danelaw history of the UK, marked by a two-fold excess of a Viking Y haplotype in central England. We also found evidence for a (different) single-centre geographical over-representation of one haplotype, both for APOC3-A4-A5 and for IGF2. The basis of this remains obscure but neither reflect genotyping error nor correlate with the phenotypic associations by centre of these markers. A panel of SNPs relevant to cardiovascular risks traits showed neither association with geographical location nor with Y haplotypes. Conclusion: Combinations of Y haplotyping, autosomal haplotyping, and genome-wide SNP typing, taken together with phenotypic2 associations, should improve epidemiological recognition and interpretation of possible confounding by genetic subdivision.<br/
MNGAZANA- 'N NUWE HAWE VIR DIE TRANSKEI
No full textThe Transkeian government plans to build a port at the mouth of the Mngazana river. This new port will be controlled and operated by the government and will handle both imports and exports. It has also been announced that this harbour will be a free port. In this article the author points out why Port St John's was not chosen. The terms free port and free zone are explained, while the whole situation is evaluated
Plasma fibrinogen concentration predicts the risk of myocardial infarction differently in various parts of Europe: effects of beta-fibrinogen genotype and environmental factors. The HIFMECH Study.
No full textThe propensity to atherothrombotic disease differs in Europe, with high-risk regions located in the North of Europe and lowrisk regions in the South of Europe. The HIFMECH study (Hypercoagulability and Impaired Fibrinolytic function MECHanisms predisposing to myocardial infarction (MI) study) was undertaken to elucidate genetic and environmental mechanisms underlying MI based on investigations of postinfarction patients and healthy individuals recruited from Stockholm, Sweden, London, England (North of Europe), Marseille, France and San Giovanni Rotondo, Italy (South of Europe). In the present report, emphasis was placed on fibrinogen, a multifunctional protein, widely recognized as an independent predictor of atherothrombotic disease. The adjusted plasma fibrinogen concentration was an independent discriminator between cases and controls in London (SOR 3.58; 95% CI 1.31; 9.83), but not in the other centres. Genotyping for six beta-fibrinogen promoter single nucleotide polymorphisms was performed of which -249C/T, -455G/A and -854G/A were used in analysis as a consequence of the linkage disequilibrium pattern. Four haplotypes, with similar distribution across Europe, were detected: CGG (46.7%), CAG (20.3%), TGG (18.2%) and CGA (14.8%). A significant haplotype effect on plasma fibrinogen concentration was observed in patients (p < 0.001) but not in controls (p = 0.08).The -455G/A genotype related to plasma fibrinogen concentration amongst patients along with centre and IL-6 concentration (together explaining 11.5% of the variation), whereas predictors amongst controls included centre, body mass index, IL-6 and smoking habit (explaining 15.7%). Thus, plasma fibrinogen concentration contributes differently to MI across Europe, and a disease-related stimulus is required to evoke allele-specific regulation of fibrinogen synthesi
Apolipoprotein AIV gene variant S347 is associated with increased risk of coronary heart disease and lower plasma apolipoprotein AIV levels
No full textThe impact of common variants in the apolipoprotein gene cluster (APOC3-A4-A5) on prospective coronary heart disease (CHD) risk was examined in healthy UK men. Of the 2808 men followed over 9 years, 187 had a clinically defined CHD event. Examination of 9 single nucleotide polymorphisms (SNPs) in this group revealed that homozygotes for APOA4 S347 had significantly increased risk of CHD [hazard ratio (HR) of 2.07 (95%CI 1.04 to 4.12)], whereas men homozygous for APOC3 1100T were protected [HR 0.28 (95%CI 0.09 to 0.87)]. In stepwise multiple regression analysis, after entering all the variants and adjusting for established risk factors APOA4 T347S alone remained in the model. Using all nine SNPs, the highest risk-estimate haplotypes carried APOA4 S347 and rare alleles of the two flanking intergenic markers. The protective effect of APOC3 1100T could be explained by negative linkage disequilibrium with these alleles. To determine the association of APOA4 T347S with apoAIV levels, the relationship was examined in 1600 healthy young European men and women. S347 homozygotes had significantly lower apoAIV plasma levels (13.64±0.59 mg/dL) compared with carriers of the T347 allele (14.90±0.12 mg/dL) (P=0.035). These results demonstrate that genetic variation in and around APOA4, independent of the effects of triglyceride, is associated with risk of CHD and apoAIV levels, supporting an antiatherogenic role for apoAIV
The efficacy, safety, and immunogenicity of plague vaccines: A systematic literature review
No full textPlague remains endemic in many parts of the world, and despite efforts, no preventative vaccine is available. We performed a systemic review of available randomised controlled trials (RCTs) of live, attenuated, or killed plague vaccines vs. placebo, no intervention, or other plague vaccine to evaluate their efficacy, safety, and immunogenicity. Data sources included MEDLINE, Embase, and the Cochrane Library; clinical trial registers; and reference lists of included studies. Primary outcomes were efficacy, safety, and immunogenicity. Risk of bias was assessed using the Cochrane Collaborations tool. Only 2 RCTs, both on subunit vaccines, were included out of the 75 screened articles. The 2 trials included 240 participants with a follow-up of 3 months and 60 participants with a follow-up of 13 months, respectively. Safety evidence was limited, but both vaccines were well tolerated, with only mild to moderate adverse events. Both vaccines were immunogenic in a dose-dependent manner. However, given the limited data identified in this systematic review, we are unable to quantify the efficacy of vaccines to prevent plague, as well as their long-term safety and immunogenicity. More trials of plague vaccines are needed to generate additional evidence of their long-term effects
Analysis of Passive Attitude Stabilisation and Deorbiting of Satellites in Low Earth Orbit
No full textOrbital debris poses a serious threat to ongoing operations in space. Recognising this threat, the European Commission has funded the three-year Technology for Self Removal (TeSeR) project with the goal of developing a standard scalable Post Mission Disposal (PMD) module to remove satellites from orbit following the completion of their mission. As the project coordinator and key member of the TeSeR Project, Airbus Defence and Space Germany will invest significant resources in achieving this goal over the course of the project. This thesis details the initial analysis of potential PMD module designs conducted by the author during an internship within the AOCS/GNC department of Airbus Defence and Space Friedrichshafen between 1 April 2016 and 31 August 2016. Three main concepts, drag sails, drag balloons and Electrodynamic Tethers (EDTs), were evaluated during this time with an emphasis on determining the ability of each design to permit passive attitude stabilisation of the satellite during PMD. Following the required modification of a pre-existing MATLAB/Simulink model, several key findings were made for each device concept. It was found that no drag sail designs investigated permitted passive aerodynamic attitude stabilisation at orbit heights above 550 km. When deorbiting from 800 km, however, the lack of the desired and stable attitude was not found to have a significant increase on the deorbit time or the area‑time product. Drag balloon designs were predicted to be comparatively unstable and less mass efficient for deorbiting purposes, with area‑time products up to approximately 50 per cent higher than the equivalent mass drag sail designs. In spite of this, unstable drag balloons were found to provide shorter deorbit times than stable balloons due to the contribution of the satellite body and solar array to the total frontal area of the satellite. This indicated that attitude stabilisation is not required for satellites equipped with drag balloon devices. Modelling of bare EDTs suggested that tethers with lengths of 1000 metres or more would not permit passive attitude stabilisation at an orbit height of 800 km. Simulation of a 500 metre EDT, however, indicated that passive attitude stabilisation can be achieved with EDT devices and proved that EDTs can generate significantly higher drag forces than aerodynamic devices while possessing a significantly lower device mass. Following the analysis of these results, a recommendation was made for future work to be aimed at improving the EDT model used in this investigation
First-year students working with exemplars: Promoting self-efficacy, self-monitoring and self-regulation
No full textIf students are to become independent learners they must be provided with opportunities to develop the capacity to monitor and regulate their learning from the outset of their academic careers. In this paper we explore first year undergraduate students’ experiences and perceptions regarding the use of exemplars, with reference to the development of student self-regulation. The study was carried out at a tertiary education institution in a large city in New Zealand where the second author was employed as a lecturer. In her role as a teacher, this author used exemplars with two classes of first year students enrolled in a core introductory paper taught as part of the students undergraduate business studies degree. Data were gathered from these students through three complementary approaches: responses to a short anonymous survey at the end of each of the four sessions where exemplars were used, written notes in the teacher’s Teaching journal and semi- structured interviews at the end of the course with student volunteers. When strategically employed as part of the teaching design, it was found that exemplars have the capacity to motivate, enhance students’ self-efficacy, promote understanding of task requirements, expand knowledge, understanding and skills in relation to the structure of academic tasks, support and advance subject knowledge, and develop evaluative and productive knowledge and expertise. It was concluded the use of exemplars with these students demonstrated their potential as tools for the promotion of student self-efficacy, self-monitoring and to a lesser extent, self-regulation
Effects of wastewater pre-treatment on clogging of an intermittent sand filter
No full textIntermittent sand filters (ISFs) are widely used in rural areas to treat domestic and dilute agricultural wastewater due to their simplicity, efficacy and relative low cost. However, filter clogging reduces their operational lifetime and sustainability. To reduce the potential of filter clogging, this study examined pre-treatment of dairy wastewater (DWW) by coagulation with ferric chloride (FeCl3) prior to treatment in replicated, pilot-scale ISFs and monitored their performance over an entire milking season (301 days). Over the study duration and at the end of the study, the extent of clogging across hybrid coagulation-ISFs was quantified and the results were compared to ISFs treating raw DWW without a coagulation pre-treatment, but otherwise operated under the same conditions. During operation, biomass growth/extent of clogging was higher in ISFs treating raw DWW, which were fully clogged after 280 days of operation. The hybrid coagulation-ISFs remained fully operational until the end of the study. Examination of the filter media in both filter types showed that the ISFs treating raw DWW lost approximately 85% of their initial infiltration capacity in the uppermost layer due to biomass build-up versus 40% loss for hybrid coagulation-ISFs. Furthermore, ISFs treating raw DWW retained more organic matter and proportionally higher amounts of phosphorus, nitrogen and sulphur than the pre-treated DWW, with values decreasing with depth below the filter surface. Overall, hybrid coagulation-ISFs are likely to sustain infiltration capacity for a longer period than filters treating raw wastewater; therefore, requiring smaller surface area for treatment and minimal maintenance.The authors would like to acknowledge Teagasc for the grant of a Walsh Fellowship to the first author [funding number: RMIS-0386]. The authors appreciate the help of technical staff: Seamus McShane, Adrian Hawe, Tomas Condon & John Paul Murphy (Teagasc Moorepark), Denis Brennan (Teagasc Johnstown Castle), and Emma McDermott (Centre for Microscopy and Imaging, University of Galway).peer-reviewe
