184 research outputs found
On blocks of Deligne's category Rep(S_t)
Recently P. Deligne introduced the tensor category Rep(S_t) (for t not
necessarily an integer) which in a certain precise sense interpolates the
categories Rep(S_d) of representations of the symmetric groups S_d. In this
paper we describe the blocks of Deligne's category Rep(S_t).Comment: 43 pages, final version, includes an added appendix as well as other
modifications recommended by the refere
Recommended from our members
Energetic and Environmental Constraints on the Community Structure of Benthic Microbial Mats in Lake Fryxell, Antarctica.
Ecological communities are regulated by the flow of energy through environments. Energy flow is typically limited by access to photosynthetically active radiation (PAR) and oxygen concentration (O2). The microbial mats growing on the bottom of Lake Fryxell, Antarctica, have well-defined environmental gradients in PAR and (O2). We analyzed the metagenomes of layers from these microbial mats to test the extent to which access to oxygen and light controls community structure. We found variation in the diversity and relative abundances of Archaea, Bacteria and Eukaryotes across three (O2) and PAR conditions: high (O2) and maximum PAR, variable (O2) with lower maximum PAR, and low (O2) and maximum PAR. We found distinct communities structured by the optimization of energy use on a millimeter-scale across these conditions. In mat layers where (O2) was saturated, PAR structured the community. In contrast, (O2) positively correlated with diversity and affected the distribution of dominant populations across the three habitats, suggesting that meter-scale diversity is structured by energy availability. Microbial communities changed across covarying gradients of PAR and (O2). The comprehensive metagenomic analysis suggests that the benthic microbial communities in Lake Fryxell are structured by energy flow across both meter- and millimeter-scales
Initial results from a GIS-based unsupervised classification study of the Martian surface
Maps of thermal inertia-albedo units and thermal inertia-elevation units on Mars’ surface have been generated by choosing thresholds that fit the strongest peaks in the histograms of these datasets. The units thus defined were then interpreted as distinct mixtures of materials on the surface, such as: bright fines, rock + bedrock and ice. We have conducted an initial classification of Thermal Emission Spectrometer (TES) night-time thermal inertia and TES albedo using a hard classifier. The methods used here are largely unsupervised and differ from those of previous studies. The aim of our study is to investigate what information can be obtained by utilising unsupervised classification algorithms to investigate the distribution of thermal materials on the surface of Mars. We find that unsupervised classification reveals additional structure in the clustering and spatial distribution of surface materials with moderate-low albedo and moderate-high thermal inertia. We highlight a number of regions such as Acidalia and Valles Marineris for future detailed studies of this type.National Committee for Space Science (NCSS), National Space Society of Australia (NSSA
Airglow-CubeSat with Orientation Control by Aerospike Puff-jets
Observations of upper atmospheric emissions further the understanding of the effects of the chemiluminescent energetics of the Earth’s atmosphere. The Airglow- CubeSat will scan the desired altitudes of the mesosphere and the upper thermosphere. The resulting data is intended to help validate results collected from measurements taken from rocket profiles as well as the SABER/TIMED satellite. The Airglow-CubeSat will be monitoring the atomic oxygen green line at a wavelength of 557 nm. Research is also being conducted into the feasibility of using aerospike technology for altitude maintenance and satellite orientation control
Surgery for rheumatic heart disease in the Northern Territory, Australia, 1997-2016: what have we gained?
Background: Between 1964 and 1996, the 10-year survival of patients having valve replacement surgery for rheumatic heart disease (RHD) in the Northern Territory, Australia, was 68%. As medical care has evolved since then, this study aimed to determine whether there has been a corresponding improvement in survival.
Methods: A retrospective study of Aboriginal patients with RHD in the Northern Territory, Australia, having their first valve surgery between 1997 and 2016. Survival was examined using Kaplan-Meier and Cox regression analysis.
Findings: The cohort included 281 adults and 61 children. The median (IQR) age at first surgery was 31 (18-42) years; 173/342 (51%) had a valve replacement, 113/342 (33%) had a valve repair and 56/342 (16%) had a commissurotomy. There were 93/342 (27%) deaths during a median (IQR) follow-up of 8 (4-12) years. The overall 10-year survival was 70% (95% CI: 64% to 76%). It was 62% (95% CI: 53% to 70%) in those having valve replacement. There were 204/281 (73%) adults with at least 1 preoperative comorbidity. Preoperative comorbidity was associated with earlier death, the risk of death increasing with each comorbidity (HR: 1.3 (95% CI: 1.2 to 1.5), p50 mm Hg before surgery (HR 1.9 (95% CI: 1.2 to 3.1) p=0.007) were independently associated with death.
Interpretation: Survival after valve replacement for RHD in this region of Australia has not improved. Although the patients were young, many had multiple comorbidities, which influenced long-term outcomes. The increasing prevalence of complex comorbidity in the region is a barrier to achieving optimal health outcomes
General practitioners and emergency departments (GPED) - Efficient models of care: A mixed-methods study protocol
© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY. Published by BMJ. Introduction Pressure continues to grow on emergency departments in the UK and throughout the world, with declining performance and adverse effects on patient outcome, safety and experience. One proposed solution is to locate general practitioners to work in or alongside the emergency department (GPED). Several GPED models have been introduced, however, evidence of effectiveness is weak. This study aims to evaluate the impact of GPED on patient care, the primary care and acute hospital team and the wider urgent care system. Methods and analysis The study will be divided into three work packages (WPs). WP-A; Mapping and Taxonomy: Mapping, description and classification of current models of GPED in all emergency departments in England and interviews with key informants to examine the hypotheses that underpin GPED. WP-B; Quantitative Analysis of National Data: Measurement of the effectiveness, costs and consequences of the GPED models identified in WP-A, compared with a no-GPED model, using retrospective analysis of Hospital Episode Statistics Data. WP-C; Case Studies: Detailed case studies of different GPED models using a mixture of qualitative and quantitative methods including: non-participant observation of clinical care, semistructured interviews with staff, patients and carers; workforce surveys with emergency department staff and analysis of available local routinely collected hospital data. Prospective case study sites will be identified by completing telephone interviews with sites awarded capital funding by the UK government to implement GPED initiatives. The study has a strong patient and public involvement group that has contributed to study design and materials, and which will be closely involved in data interpretation and dissemination. Ethics and dissemination The study has been approved by the National Health Service East Midlands - Leicester South Research Ethics Committee: 17/EM/0312. The results of the study will be disseminated through peer-reviewed journals, conferences and a planned programme of knowledge mobilisation
Recommended from our members
Genomics of Loa loa, a Wolbachia-free filarial parasite of humans
Loa loa, the African eyeworm, is a major filarial pathogen of humans. Unlike most filariae, Loa loa does not contain the obligate intracellular Wolbachia endosymbiont. We describe the 91.4 Mb genome of Loa loa, and the genome of the related filarial parasite Wuchereria bancrofti, and predict 14,907 Loa loa genes based on microfilarial RNA sequencing. By comparing these genomes to that of another filarial parasite, Brugia malayi, and to several other nematode genomes, we demonstrate synteny among filariae but not with non-parasitic nematodes. The Loa loa genome encodes many immunologically relevant genes, as well as protein kinases targeted by drugs currently approved for humans. Despite lacking Wolbachia, Loa loa shows no new metabolic synthesis or transport capabilities compared to other filariae. These results suggest that the role played by Wolbachia in filarial biology is more subtle than previously thought and reveal marked differences between parasitic and non-parasitic nematodes
- …