Training Gaussian Mixture Models at Scale via Coresets

How can we train a statistical mixture model on a massive data set? In this work we show how to construct coresets for mixtures of Gaussians. A coreset is a weighted subset of the data, which guarantees that models fitting the coreset also provide a good fit for the original data set. We show that, perhaps surprisingly, Gaussian mixtures admit coresets of size polynomial in dimension and the number of mixture components, while being independent of the data set size. Hence, one can harness computationally intensive algorithms to compute a good approximation on a significantly smaller data set. More importantly, such coresets can be efficiently constructed both in distributed and streaming settings and do not impose restrictions on the data generating process. Our results rely on a novel reduction of statistical estimation to problems in computational geometry and new combinatorial complexity results for mixtures of Gaussians. Empirical evaluation on several real-world datasets suggests that our coreset-based approach enables significant reduction in training-time with negligible approximation error

The influence of globalization on medical regulation: a descriptive analysis of international medical graduates registered through alternative licensure routes in Ontario

The increasing globalization of the medical profession has influenced health policy, health human resource planning, and medical regulation in Canada. Since the early 2000s, numerous policy initiatives have been created to facilitate the entry of international medical graduates (IMGs) into the Canadian workforce. In Ontario, the College of Physicians and Surgeons of Ontario (CPSO) developed alternative licensure routes to increase the ability of qualified IMGs to obtain licenses to practice. The current study provides demographic and descriptive information about the IMGs registered through the CPSO’s alternative licensure routes between 2000 and 2012. An analysis of the characteristics and career trajectories of all IMGs practicing in the province sheds light on broader globalization trends and raises questions about the future of health human resource planning in Canada. As the medical profession becomes increasingly globalized, health policy and regulation will continue to be influenced by trends in international migration, concerns about global health equity, and the shifting demographics of the Canadian physician workforce. Implications for future policy development in the complex landscape of medical education and practice are discussed

Adipogenic and energy metabolism gene networks in longissimus lumborum during rapid post-weaning growth in Angus and Angus × Simmental cattle fed high-starch or low-starch diets

<p>Abstract</p> <p>Background</p> <p>Transcriptional networks coordinate adipocyte differentiation and energy metabolism in rodents. The level of fiber and starch in diets with adequate energy content fed to young cattle has the potential to alter intramuscular adipose tissue development in skeletal muscle. Post-weaning alterations in gene expression networks driving adipogenesis, lipid filling, and intracellular energy metabolism provide a means to evaluate long-term effects of nutrition on longissimus muscle development across cattle types.</p> <p>Results</p> <p><it>Longissimus lumborum </it>(LL) from Angus (n = 6) and Angus × Simmental (A × S; n = 6) steer calves (155 ± 10 days age) fed isonitrogenous high-starch (HiS; 1.43 Mcal/kg diet dry matter; n = 6) or low-starch (LoS; 1.19 Mcal/kg diet dry matter; n = 6) diets was biopsied at 0, 56, and 112 days of feeding for transcript profiling of 31 genes associated with aspects of adipogenesis and energy metabolism. Intake of dietary energy (9.44 ± 0.57 Mcal/d) across groups during the study did not differ but feed efficiency (weight gain/feed intake) during the first 56 days was greater for steers fed HiS. Expression of <it>PPARG </it>increased ca. 2-fold by day 56 primarily due to HiS in A × S steers. Several potential <it>PPARG</it>-target genes (e.g., <it>ACACA</it>, <it>FASN</it>, <it>FABP4</it>, <it>SCD</it>) increased 2.5-to-25-fold by day 56 across all groups, with responses (e.g., <it>FASN</it>, <it>FABP4</it>) being less pronounced in A × S steers fed LoS. This latter group of steers had markedly greater blood plasma glucose (0.99 vs. 0.79 g/L) and insulin (2.95 vs. 1.17 μg/L) by day 112, all of which were suggestive of insulin resistance. Interactions were observed for <it>FABP4</it>, <it>FASN</it>, <it>GPAM</it>, <it>SCD</it>, and <it>DGAT2</it>, such that feeding A × S steers high-starch and Angus steers low-starch resulted in greater fold-changes by day 56 or 112 (<it>GPAM</it>). Marked up-regulation of <it>INSIG1 </it>(4-to-8-fold) occurred throughout the study across all groups. <it>SREBF1 </it>expression, however, was only greater on day 112 namely due to LoS in A × S steers. The lipogenic transcription factor <it>THRSP </it>was 6-to-60-fold greater by day 56 primarily due to HiS in A × S steers, constituting the greatest response among all genes.</p> <p>Conclusion</p> <p>Results involving gene markers of mature adipocytes (e.g., <it>PPARG</it>, <it>THRSP</it>, <it>SCD</it>) provided evidence of intramuscular adipose tissue differentiation during the early portion of the growing phase. The resulting gene networks underscored a central role for <it>PPARG </it>in controlling transcription of genes which are known to co-ordinately regulate adipocyte differentiation and lipid filling in non-ruminants. Unlike rodents, <it>INSIG1 </it>appears to play an important role in cattle muscle adipogenesis. We propose that a network of transcription regulators and nuclear receptors including <it>PPARG</it>-target genes,<it> INSIG1</it>, and <it>THRSP</it>, coordinate activation of adipocyte differentiation and lipid filling at an early age.</p

National Program for Genetic Improvement of Feed Efficiency in Beef Cattle

Our goal is to sustainably reduce feed resources required to produce beef via the rapid development and deployment of novel nutritional, genomic and genetic improvement technologies. We will strengthen the international competitiveness of US agriculture and enable increased food production by increasing the animal protein produced without additional feed inputs and with a reduced greenhouse gas footprint

Relationship Between Morbidity and Performance in Feedlot Cattle

Five datasets from Canada, Oklahoma, Illinois, and Nebraska were used to determine the impact of bovine respiratory disease (BRD) on performance, with emphasis on dry matter intake (DMI) and feed to gain ratio (F:G). Data included pens and individually fed cattle. In general, cattle treated for BRD had lower DMI and average daily gain (ADG) with little to no effect on F:G. When BRD occured early in the feeding period (days), little change in performance was observed

1972: Abilene Christian College Bible Lectures - Full Text

THE CHURCH AND THE FUTURE Being the Abilene Christian College Annual Bible Lectures 1972 Published by ABILENE CHRISTIAN COLLEGE BOOK STORE ACC Station Abilene, Texas 7960

Developing a core outcome set for the health outcomes for children and adults with congenital oesophageal atresia and/or tracheo-oesophageal fistula:OCELOT task group study protocol

Introduction Heterogeneity in reported outcomes of infants with oesophageal atresia (OA) with or without tracheo-oesophageal fistula (TOF) prevents effective data pooling. Core outcome sets (COS) have been developed for many conditions to standardise outcome reporting, facilitate meta-analysis and improve the relevance of research for patients and families. Our aim is to develop an internationally-agreed, comprehensive COS for OA-TOF, relevant from birth through to transition and adulthood. Methods and analysis A long list of outcomes will be generated using (1) a systematic review of existing studies on OA-TOF and (2) qualitative research with children (patients), adults (patients) and families involving focus groups, semistructured interviews and self-reported outcome activity packs. A two-phase Delphi survey will then be completed by four key stakeholder groups: (1) patients (paediatric and adult); (2) families; (3) healthcare professionals; and (4) researchers. Phase I will include stakeholders individually rating the importance and relevance of each long-listed outcome using a 9-point Likert scale, with the option to suggest additional outcomes not already included. During phase II, stakeholders will review summarised results from phase I relative to their own initial score and then will be asked to rescore the outcome based on this information. Responses from phase II will be summarised using descriptive statistics and a predefined definition of consensus for inclusion or exclusion of outcomes. Following the Delphi process, stakeholder experts will be invited to review data at a consensus meeting and agree on a COS for OA-TOF. Ethics and dissemination Ethical approval was sought through the Health Research Authority via the Integrated Research Application System, registration no. 297026. However, approval was deemed not to be required, so study sponsorship and oversight were provided by Alder Hey Children’s NHS Foundation Trust. The study has been prospectively registered with the COMET Initiative. The study will be published in an open access forum.</p

Developing a core outcome set for the health outcomes for children and adults with congenital oesophageal atresia and/or tracheo-oesophageal fistula: OCELOT task group study protocol

Introduction: Heterogeneity in reported outcomes of infants with oesophageal atresia (OA) with or without tracheo-oesophageal fistula (TOF) prevents effective data pooling. Core outcome sets (COS) have been developed for many conditions to standardise outcome reporting, facilitate meta-analysis and improve the relevance of research for patients and families. Our aim is to develop an internationally-agreed, comprehensive COS for OA-TOF, relevant from birth through to transition and adulthood. Methods and analysis: A long list of outcomes will be generated using (1) a systematic review of existing studies on OA-TOF and (2) qualitative research with children (patients), adults (patients) and families involving focus groups, semistructured interviews and self-reported outcome activity packs. A two-phase Delphi survey will then be completed by four key stakeholder groups: (1) patients (paediatric and adult); (2) families; (3) healthcare professionals; and (4) researchers. Phase I will include stakeholders individually rating the importance and relevance of each long-listed outcome using a 9-point Likert scale, with the option to suggest additional outcomes not already included. During phase II, stakeholders will review summarised results from phase I relative to their own initial score and then will be asked to rescore the outcome based on this information. Responses from phase II will be summarised using descriptive statistics and a predefined definition of consensus for inclusion or exclusion of outcomes. Following the Delphi process, stakeholder experts will be invited to review data at a consensus meeting and agree on a COS for OA-TOF. Ethics and dissemination: Ethical approval was sought through the Health Research Authority via the Integrated Research Application System, registration no. 297026. However, approval was deemed not to be required, so study sponsorship and oversight were provided by Alder Hey Children’s NHS Foundation Trust. The study has been prospectively registered with the COMET Initiative. The study will be published in an open access forum

Developing a core outcome set for the health outcomes for children and adults with congenital oesophageal atresia and/or tracheo-oesophageal fistula:OCELOT task group study protocol

Introduction Heterogeneity in reported outcomes of infants with oesophageal atresia (OA) with or without tracheo-oesophageal fistula (TOF) prevents effective data pooling. Core outcome sets (COS) have been developed for many conditions to standardise outcome reporting, facilitate meta-analysis and improve the relevance of research for patients and families. Our aim is to develop an internationally-agreed, comprehensive COS for OA-TOF, relevant from birth through to transition and adulthood. Methods and analysis A long list of outcomes will be generated using (1) a systematic review of existing studies on OA-TOF and (2) qualitative research with children (patients), adults (patients) and families involving focus groups, semistructured interviews and self-reported outcome activity packs. A two-phase Delphi survey will then be completed by four key stakeholder groups: (1) patients (paediatric and adult); (2) families; (3) healthcare professionals; and (4) researchers. Phase I will include stakeholders individually rating the importance and relevance of each long-listed outcome using a 9-point Likert scale, with the option to suggest additional outcomes not already included. During phase II, stakeholders will review summarised results from phase I relative to their own initial score and then will be asked to rescore the outcome based on this information. Responses from phase II will be summarised using descriptive statistics and a predefined definition of consensus for inclusion or exclusion of outcomes. Following the Delphi process, stakeholder experts will be invited to review data at a consensus meeting and agree on a COS for OA-TOF. Ethics and dissemination Ethical approval was sought through the Health Research Authority via the Integrated Research Application System, registration no. 297026. However, approval was deemed not to be required, so study sponsorship and oversight were provided by Alder Hey Children’s NHS Foundation Trust. The study has been prospectively registered with the COMET Initiative. The study will be published in an open access forum.</p