7 research outputs found

    Processing of ultrafine-size particulate metal matrix composites by advanced shear technology

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    Copyright @ 2009 ASM International. This paper was published in Metallurgical & Materials Transactions A 40A(3) and is made available as an electronic reprint with the permission of ASM International. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplications of any material in this paper for a fee or for commercial purposes, or modification of the content of this paper are prohibited.Lack of efficient mixing technology to achieve a uniform distribution of fine-size reinforcement within the matrix and the high cost of producing components have hindered the widespread adaptation of particulate metal matrix composites (PMMCs) for engineering applications. A new rheo-processing method, the melt-conditioning high-pressure die-cast (MC-HPDC) process, has been developed for manufacturing near-net-shape components of high integrity. The MC-HPDC process adapts the well-established high shear dispersive mixing action of a twin-screw mechanism to the task of overcoming the cohesive force of the agglomerates under a high shear rate and high intensity of turbulence. This is followed by direct shaping of the slurry into near-net-shape components using an existing cold-chamber die-casting process. The results indicate that the MC-HPDC samples have a uniform distribution of ultrafine-sized SiC particles throughout the entire sample in the as-cast condition. Compared to those produced by conventional high-pressure die casting (HPDC), MC-HPDC samples have a much improved tensile strength and ductility.EP-SR

    Associations of autozygosity with a broad range of human phenotypes

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    In many species, the offspring of related parents suffer reduced reproductive success, a phenomenon known as inbreeding depression. In humans, the importance of this effect has remained unclear, partly because reproduction between close relatives is both rare and frequently associated with confounding social factors. Here, using genomic inbreeding coefficients (FROH) for >1.4 million individuals, we show that FROH is significantly associated (p < 0.0005) with apparently deleterious changes in 32 out of 100 traits analysed. These changes are associated with runs of homozygosity (ROH), but not with common variant homozygosity, suggesting that genetic variants associated with inbreeding depression are predominantly rare. The effect on fertility is striking: FROH equivalent to the offspring of first cousins is associated with a 55% decrease [95% CI 44–66%] in the odds of having children. Finally, the effects of FROH are confirmed within full-sibling pairs, where the variation in FROH is independent of all environmental confounding

    Turnover in information systems development projects - Managing forgetting

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    PACIS 2008 - 12th Pacific Asia Conference on Information Systems: Leveraging ICT for Resilient Organizations and Sustainable Growth in the Asia Pacific Regio

    Erratum to: Cross-ancestry genome-wide association analysis of corneal thickness strengthens link between complex and Mendelian eye diseases (Nature Communications, (2018), 9, 1, (1864), 10.1038/s41467-018-03646-6)

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    10.1038/s41467-018-07819-1Nature Communications10115

    Colorectal Endoscopic Stenting Trial (CReST) for obstructing left-sided colorectal cancer: randomized clinical trial

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    Background Colorectal cancer often presents with obstruction needing urgent, potentially life-saving decompression. The comparative efficacy and safety of endoluminal stenting versus emergency surgery as initial treatment for such patients is uncertain. Methods Patients with left-sided colonic obstruction and radiological features of carcinoma were randomized to endoluminal stenting using a combined endoscopic/fluoroscopic technique followed by elective surgery 1–4 weeks later, or surgical decompression with or without tumour resection. Treatment allocation was via a central randomization service using a minimization procedure stratified by curative intent, primary tumour site, and severity score (Acute Physiology And Chronic Health Evaluation). Co-primary outcome measures were duration of hospital stay and 30-day mortality. Secondary outcomes were stoma formation, stenting completion and complication rates, perioperative morbidity, 6-month survival, 3-year recurrence, resource use, adherence to chemotherapy, and quality of life. Analyses were undertaken by intention to treat. Results Between 23 April 2009 and 22 December 2014, 245 patients from 39 hospitals were randomized. Stenting was attempted in 119 of 123 allocated patients (96.7 per cent), achieving relief of obstruction in 98 of 119 (82.4 per cent). For the 89 per cent treated with curative intent, there were no significant differences in 30-day postoperative mortality (3.6 per cent (4 of 110) versus 5.6 per cent (6 of 107); P = 0.48), or duration of hospital stay (median 19 (i.q.r. 11–34) versus 18 (10–28) days; P = 0.94) between stenting followed by delayed elective surgery and emergency surgery. Among patients undergoing potentially curative treatment, stoma formation occurred less frequently in those allocated to stenting than those allocated to immediate surgery (47 of 99 (47.5 per cent) versus 72 of 106 (67.9 per cent); P = 0.003). There were no significant differences in perioperative morbidity, critical care use, quality of life, 3-year recurrence or mortality between treatment groups. Conclusion Stenting as a bridge to surgery reduces stoma formation without detrimental effects. Registration number: ISRCTN13846816 (http://www.controlled-trials.com)

    Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

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    From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions. © Copyright
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