26,500 research outputs found
Progress and priorities in reducing the time to cancer diagnosis
Key developments in early diagnosis research and policy since the publication of the highly cited BJC review âIs increased time to diagnosis and treatment associated with poorer outcomes?â by Neal et al. in 2015 are summarised. Progress achieved since 2015 is described and priorities for further research identified
Exhaustive generation of -critical -free graphs
We describe an algorithm for generating all -critical -free
graphs, based on a method of Ho\`{a}ng et al. Using this algorithm, we prove
that there are only finitely many -critical -free graphs, for
both and . We also show that there are only finitely many
-critical graphs -free graphs. For each case of these cases we
also give the complete lists of critical graphs and vertex-critical graphs.
These results generalize previous work by Hell and Huang, and yield certifying
algorithms for the -colorability problem in the respective classes.
Moreover, we prove that for every , the class of 4-critical planar
-free graphs is finite. We also determine all 27 4-critical planar
-free graphs.
We also prove that every -free graph of girth at least five is
3-colorable, and determine the smallest 4-chromatic -free graph of
girth five. Moreover, we show that every -free graph of girth at least
six and every -free graph of girth at least seven is 3-colorable. This
strengthens results of Golovach et al.Comment: 17 pages, improved girth results. arXiv admin note: text overlap with
arXiv:1504.0697
Nonlinear multi-scale homogenization with different structural models at different scales
We present an extension of the computational homogenization theory to cases where different structural models are used at different scales and no energy potential can be defined at the small scale. We observe that volumetric averaging, which is not applicable in such cases unless similarities exist in the macro-scale and micro-scale models, is not a necessary prerequisite to carry out computational homogenization. At each material point of the macro-model, we replace the conventional representative volume element with a representative domain element (RDE). To link the large-scale and small-scale problems, we then introduce a linear operator, mapping the smooth part of the small-scale displacement field of each RDE to the large-scale strain field and a trace operator to impose boundary conditions in the RDE. The latter is defined on the basis of engineering judgement, analogously to the conventional theory. A generalized Hillâs condition, rather than being invoked, is derived from duality principles and is used to recover the stress measures at the large scale. For the implementation in a nonlinear finite-element analysis, âcontrol nodesâ and constraint equationsare used. The effectiveness of the procedure is demonstrated for three beam-to-truss example problems, for which multi-scale convergence is numerically analysed.Lloydâs Register EME
Current practice in the management of frontal sinus fractures
Fractures of the frontal sinus are seen predominantly, although not exclusively, in young men and are usually the result of road traffic accidents or falls. These types of injury may present to either ENT, Maxillofacial, Plastic or Neurosurgery teams, and understanding of a clear management protocol is desirable for each of the specialties. The optimal management of these injuries is becoming more uniformly adopted although some areas of contention still persist. The aim of treatment has always been directed at creating a 'safe sinus' that is not complicated by the late sequelae of infection or mucocele formation. The difficulty lies in being able to predict which patients are likely to develop these complications. The aim of this paper is to evaluate the literature and offer a rationale for the management of these injuries
Rapunzel Syndrome: a rare cause of acute small bowel obstruction
The Rapunzel syndrome is a very rare condition where trichobezoar hasextended up to the small bowel. Here we are reporting a rare case of Rapunzel syndrome in an adolescent girl with history of trichophagia who presented with small bowel obstruction. Patient underwent exploratory laparotomy and bezoar was removed through gastrotomy. Post-operative course was unremarkable.KEY WORDS: Rapunzel syndrome; Trichobezoars; Psychotherapy; Gastrotom
Recent Progress in Neutron Star Theory
This review contains chapters discussing: Energy density fluctionals of
nuclear matter, Many-body theory of nucleon matter, Hadronic and quark matter,
Mixtures of phases in dense matter, Neutron star observations and predictions.Comment: 33 pages +13 figs., Ann. Rev. Nucl. & Part. Science, 200
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Design Principles for High-Capacity Mn-Based Cation-Disordered Rocksalt Cathodes
Mn-based Li-excess cation-disordered rocksalt (DRX) oxyfluorides are promising candidates for next-generation rechargeable battery cathodes owing to their large energy densities, the earth abundance, and low cost of Mn. In this work, we synthesized and electrochemically tested four representative compositions in the Li-Mn-O-F DRX chemical space with various Li and F content. While all compositions achieve higher than 200 mAh gâ1 initial capacity and good cyclability, we show that the Li-site distribution plays a more important role than the metal-redox capacity in determining the initial capacity, whereas the metal-redox capacity is more closely related to the cyclability of the materials. We apply these insights and generate a capacity map of the Li-Mn-O-F chemical space, LixMn2-xO2-yFy (1.167 †x †1.333, 0 †y †0.667), which predicts both accessible Li capacity and Mn-redox capacity. This map allows the design of compounds that balance high capacity with good cyclability
The politics of alcohol policy in Nigeria: a critical analysis of how and why brewers use strategic ambiguity to supplant policy initiatives
The global call by the World Health Assembly (WHA) to control the rising alcohol-related problems caused by harmful consumption through policy became necessary in 2005 due to the recognition of the fact that many countries did not have alcohol policies. This gave rise to the adoption of a ten-point policy strategy by the World Health Organization (WHO) Member States in 2010. Against this backdrop, many countries adopted alcohol policies to reduce harmful alcohol consumption. Nigeria was one of the WHO Member Countries that adopted the resolution. Nigeria is among the 30 countries with the highest per capita consumption and alcohol-related problems, yet has not formulated alcohol policy to date. This paper draws on Eisenbergâs Strategic Ambiguity Model to explore the role of brewers in supplanting alcohol policy initiatives in Nigeria. It argues that the leading alcohol producers in Nigeria have been the main reason alcohol policies have not been formulated. The article focuses on why their campaigns for responsible drinking, promotions, sponsorships and âstrategic social responsibilitiesâ may have increased since the WHA made the call and the WHO adopted the resolution in 2010. It concludes by arguing that there is an urgent need to formulate policies drawing from the WHO resolution to curtail the activities of these brewers and reduce harmful consumption
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