5,911 research outputs found

    Standards of Review in Texas

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    Tree-Independent Dual-Tree Algorithms

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    Dual-tree algorithms are a widely used class of branch-and-bound algorithms. Unfortunately, developing dual-tree algorithms for use with different trees and problems is often complex and burdensome. We introduce a four-part logical split: the tree, the traversal, the point-to-point base case, and the pruning rule. We provide a meta-algorithm which allows development of dual-tree algorithms in a tree-independent manner and easy extension to entirely new types of trees. Representations are provided for five common algorithms; for k-nearest neighbor search, this leads to a novel, tighter pruning bound. The meta-algorithm also allows straightforward extensions to massively parallel settings.Comment: accepted in ICML 201

    The Principle of Symmetric Criticality in General Relativity

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    We consider a version of Palais' Principle of Symmetric Criticality (PSC) that is applicable to the Lie symmetry reduction of Lagrangian field theories. PSC asserts that, given a group action, for any group-invariant Lagrangian the equations obtained by restriction of Euler-Lagrange equations to group-invariant fields are equivalent to the Euler-Lagrange equations of a canonically defined, symmetry-reduced Lagrangian. We investigate the validity of PSC for local gravitational theories built from a metric. It is shown that there are two independent conditions which must be satisfied for PSC to be valid. One of these conditions, obtained previously in the context of transverse symmetry group actions, provides a generalization of the well-known unimodularity condition that arises in spatially homogeneous cosmological models. The other condition seems to be new. The conditions that determine the validity of PSC are equivalent to pointwise conditions on the group action alone. These results are illustrated with a variety of examples from general relativity. It is straightforward to generalize all of our results to any relativistic field theory.Comment: 46 pages, Plain TeX, references added in revised versio

    Inclusive Masculinity and Facebook Photographs Among Early Emerging Adults at a British University

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    Central to debates about the construction of masculinity in sociology is the influence of culture and what constitutes acceptable displays of masculinity. This article adopts a novel approach in examining this question. It adopts a summative content analysis, combined with a semiotic analysis, of 1,100 Facebook photographs, in order to explore the underlying meanings within the photos and the performances of masculinity. Facebook photographs from 44, straight, White, male, early emerging adults attending the same university are used as a representation of an individual’s ideal self. These are then analyzed in order to determine the behaviors endorsed by peer culture. It was found that the sample overwhelmingly adopted inclusive behaviors (including homosocial tactility, dancing, and kissing each other), and inclusive masculinity theory was utilized to contextualize participants’ constructions of masculinity. Thus, this research shows that emerging adult males at this university construct their masculine identities away from previous orthodox archetypes. It is argued that the reducing importance of gendered behavior patterns may represent an adoption of what are perceived as wider cultural norms and act as a symbol of adulthood to these early emerging adults

    An estimate of the effectiveness of an in-vehicle automatic collision notification system in reducing road crash fatalities in South Australia

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    Objectives: The aim of this study was to estimate the potential effectiveness of an in - vehicle automatic collision notification (ACN) system in reducing all road crash fatalities in South Australia (SA). Methods: For the years 2008 to 2009 traffic accident reporting system (TARS) data, emergency medical services (EMS) road crash dispatch data and Co roner ‟s reports were matched and examined. This was done t o initially determine the extent to which there was difference s between the reported time of a fatal road crash in the mass crash data and the time EMS were notified and dispatched . In the sub - set of fatal crashes where there was a delay, injuries detailed by a forensic pathologist in individual Coroner ‟s reports were examined to determine the likelihood of survival had there not been a delay in emergency medical assistance. Results : In 25 % (N= 53 ) of fatalities in SA in the period 2008 to 2009, there was a delay in the notification of the crash event, and hence dispatch of EMS , that exceed ed 10 minutes. In the two - year crash period, f ive people were likely to have survived through more prompt crash notification enabling quicker emergency medical assistance. Additionally three people potentially would have survived if surgical intervention (or emergency medical assistance to sustain lif e until surgery) occurred more promptly.G Ponte, G.A. Ryan, R.W.G. Anderso

    The characteristics of fatal crashes in South Australia involving a delay in notifying Emergency Medical Services

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    This study examined the 191 fatal crashes and 218 fatalities occurring in South Australia in the period 2008-2009. A sub-set of these fatal crashes was identified where there was a delay between the time of the crash and the time Emergency Medical Services (EMS) were notified and subsequently dispatched to render medical assistance. It was found that 21.5% (N=41) of fatal crashes had an EMS notification delay exceeding 10 minutes; this accounted for 23.4% of fatalities (N=51). These fatal crashes were examined in more detail including injuries detailed by the forensic pathologist in available coroner reports. It was found that most of the crash notification delays occurred in rural areas and that 2.2% of all fatalities might have been avoided if earlier crash notification to emergency medical services had occurred. This paper will report on the characteristics of these fatal crashes, a mechanism by which crash notification delays might be reduced and factors that might affect successful reduction in delays.Ponte, G., Anderson, RWG. & Ryan, GA.http://www.rsrpe2013.com.au/conference-papers/conference-papers.ph

    Polyamine biosynthesis is critical for growth and differentiation of the pancreas

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    The pancreas, in most studied vertebrates, is a compound organ with both exocrine and endocrine functions. The exocrine compartment makes and secretes digestive enzymes, while the endocrine compartment, organized into islets of Langerhans, produces hormones that regulate blood glucose. High concentrations of polyamines, which are aliphatic amines, are reported in exocrine and endocrine cells, with insulin-producing β cells showing the highest concentrations. We utilized zebrafish as a model organism, together with pharmacological inhibition or genetic manipulation, to determine how polyamine biosynthesis functions in pancreatic organogenesis. We identified that inhibition of polyamine biosynthesis reduces exocrine pancreas and β cell mass, and that these reductions are at the level of differentiation. Moreover, we demonstrate that inhibition of ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis, phenocopies inhibition or knockdown of the enzyme deoxyhypusine synthase (DHS). These data identify that the pancreatic requirement for polyamine biosynthesis is largely mediated through a requirement for spermidine for the downstream posttranslational modification of eIF5A by its enzymatic activator DHS, which in turn impacts mRNA translation. Altogether, we have uncovered a role for polyamine biosynthesis in pancreatic organogenesis and identified that it may be possible to exploit polyamine biosynthesis to manipulate pancreatic cell differentiation

    Molecular Mechanisms of Nonalcoholic Fatty Liver Disease: Potential Role for 12-Lipoxygenase

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    Nonalcoholic fatty liver disease (NAFLD) is a spectrum of pathologies associated with fat accumulation in the liver. NAFLD is the most common cause of liver disease in the United States, affecting up to a third of the general population. It is commonly associated with features of metabolic syndrome, particularly insulin resistance. NAFLD shares the basic pathogenic mechanisms with obesity and insulin resistance, such as mitochondrial, oxidative and endoplasmic reticulum stress. Lipoxygenases catalyze the conversion of poly-unsaturated fatty acids in the plasma membrane—mainly arachidonic acid and linoleic acid—to produce oxidized pro-inflammatory lipid intermediates. 12-Lipoxygenase (12-LOX) has been studied extensively in setting of inflammation and insulin resistance. As insulin resistance is closely associated with development of NAFLD, the role of 12-LOX in pathogenesis of NAFLD has received increasing attention in recent years. In this review we discuss the role of 12-LOX in NAFLD pathogenesis and its potential role in emerging new therapeutics
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