7440 research outputs found
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Passive defensive traits are not good predictors of predation for in faunal reef bivalves
No full textPredation is a key biotic interaction that shapes ecological communities. Defensive morphological traits are thought to improve prey survivorship, and knowing which traits aid survivorship is critical to understanding predator-prey dynamics and their impact on community composition. Paleontological studies that use optimal foraging theory and single species experiments suggest that shell size and thickness are traits that affect the outcome of mollusk drilling predation. We analyzed the effectiveness of these morphological traits using a tropical molluscan assemblage from the One Tree Reef lagoon (southern Great Barrier Reef, Australia). Shell mass, shape, thickness, and predation frequency were measured in five bivalve species (n = 804) constituting 80% of the predators' diet. Multiple regression determined that shell mass, shell thickness, and the interaction between the two were important predictors of predation. Drilling was more likely in thinner and larger individuals. However, support for the model that included species identity was markedly stronger, indicating that the morphological traits measured are not general predictors of predation across the five prey species we studied. That is, trait-only models are inadequate for explaining predator-prey dynamics at the community level. Alternatively, active behavioral defenses related to infaunality (like burrowing) appear to be stronger drivers of morphology in this system. Care should be taken when extrapolating results from experiments to communities or large temporal scales, as species with similar traits may not necessarily elicit the same response from predators.9 page(s
Spinal cord injury caused by stab wounds : incidence, natural history, and relevance for future research
No full textSpinal cord injury caused by stab wounds (SCISW) results from a partial or complete transection of the cord, and presents opportunities for interventional research. It is recognized that there is low incidence, but little is known about the natural history or the patient's suitability for long-term clinical outcome studies. This study aims to provide population-based evidence of the demographics of SCISW, and highlight the issues regarding the potential for future research. The database of the Queen Elizabeth National Spinal Injuries Unit (QENSIU), the sole center for treating SCI in Scotland, was reviewed between 1994 and 2013 to ascertain the incidence, demographics, functional recovery, and mortality rates for new SCISW. During this 20 year period, 35 patients with SCISW were admitted (97.1% male, mean age 30.0 years); 31.4% had a cervical injury, 60.0% had a thoracic injury, and 8.6% had a lumbar injury. All had a neurological examination, with 42.9% diagnosed as motor complete on admission and 77.1% discharged as motor incomplete. A total of 70.4% of patients with an American Spinal Injury Association Impairment Scale (AIS) level of A to C on admission had an improved AIS level on discharge. Nine (25.7%) patients have died since discharge, with mean life expectancy for these patients being 9.1 years after injury (20-65 years of age). Patients had higher levels of comorbidities, substance abuse, secondary events, and poor compliance compared with the general SCI population, which may have contributed to the high mortality rate observed post-discharge. The low incidence, heterogeneous nature, spontaneous recovery rate, and problematic follow-up makes those with penetrating stab injuries of the spinal cord a challenging patient group for SCI research.6 page(s
On the throughput-delay tradeoff in georouting networks
No full textWe study the scaling properties of a georouting scheme in a wireless multi-hop network of n mobile nodes. Our aim is to increase the network capacity quasi-linearly with n, while keeping the average delay bounded. In our model, we consider mobile nodes moving according to an independent identically distributed random walk with velocity v and transmitting packets to randomly chosen fixed and known destinations. The average packet delivery delay of our scheme is of order 1/v, and it achieves network capacity of order (n log). This shows a practical throughput-delay tradeoff, in particular when compared with the seminal result of Gupta and Kumar, which shows network capacity of order (n/logn)1/2 and negligible delay and the groundbreaking result of Grossglauser and Tse, which achieves network capacity of order n but with an average delay of order n/v. The foundation of our improved capacity and delay tradeoff relies on the fact that we use a mobility model that contains straight-line segments, a model that we consider more realistic than classic Brownian motions. We confirm the generality of our analytical results using simulations under various interference models.13 page(s
Validation of the Leuven postprandial distress scale (LPDS), a questionnaire for symptom assessment in patients suffering from functional dyspepsia/postprandial distress syndrome (FD-PDS)
No full text1 page(s
When the personal enables the independent : taking the library to the students
No full textWestern Sydney University has the most diverse, and also the most disadvantaged, student body of any university in Australia. First-year students are hampered in general, by a lack of preparation for the demands of university study, suffering a deficit in what could be termed Academic Motivational Literacy. They also, more specifically, typically arrive at university with little preparation for Information–Research Literacy. In practice, it means that these students are not only unfamiliar with library resources, they are not motivated to find out for themselves what is available on campus or online. In response to this need, many of these first-year students are expected to undertake a core Academic English literacy-skills subject, where independent research is an essential requirement. Rather than seeing student reluctance to seek out library resources as an agential decision, it was viewed as an opportunity to redress deficit through facilitative teaching. A collaborative project was then designed and funded in response to this need, which saw library staff attend hundreds of tutorials and actively team-teach the basics of research with unit tutors. The success of this project has seen it become a regular fixture in the academic calendar.15 page(s
Genetic association at the 9p21 glaucoma locus contributes to sex bias in normal-tension glaucoma
No full textPurpose. Many genome-wide association studies have identified common single nucleotide polymorphisms (SNPs) at the 9p21 glaucoma locus (CDKN2B/CDKN2B-AS1) to be significantly associated with primary open-angle glaucoma (POAG), with association being stronger in normal tension glaucoma (NTG) and advanced glaucoma. We aimed to determine whether any observed differences in genetic association at the 9p21 locus are influenced by sex. Methods. Sex was assessed as a risk factor for POAG for 2241 glaucoma participants from the Australian and New Zealand Registry of Advanced Glaucoma, the Glaucoma Inheritance Study in Tasmania, and the Flinders Medical Centre. A total of 3176 controls were drawn from the Blue Mountains Eye Study and South Australia: 1523 advanced POAG and 718 nonadvanced POAG cases were genotyped along with 3176 controls. We selected 13 SNPs at the 9p21 locus, and association results were subanalyszd by sex for high-tension glaucoma (HTG) and NTG. Odds ratios (ORs) between sexes were compared. Results. A sex bias was present within advanced NTG cases (57.1% female versus 42.9% male, P = 0.0026). In all POAG cases, the strongest associated SNP at 9p21 was rs1063192 (OR, 1.43; P = 4 × 10⁻¹⁸). This association was stronger in females (OR, 1.5; P = 5 × 10⁻¹³) than inmales (OR, 1.35; P = 7 × 10⁻⁷), with a statistically significant difference in female to male OR comparison (P = 1.0 × 10⁻²). An NTG to HTG subanalysis yielded statistically significant results only in females (OR, 1.63; P = 1.5 × 10⁻⁴) but not in males (OR, 1.15; P = 2.8 × 10⁻¹), with a statistically significant difference in female to male OR comparison (P = 1.4 × 10⁻⁴). Conclusions. This study demonstrated that female sex is a risk factor for developing advanced NTG. The stronger genetic signals at the 9p21 locus among females may contribute at least in part to the observed sex bias for NTG.6 page(s
Fecal impaction in the emergency department : an analysis of frequency and associated charges in 2011
No full textGoals: The aim of this study was to analyze the incidence and associated charges of fecal impaction for trends in hospital and patient demographics in emergency departments (ED) across the United States. Background: In 2010, an ICD-9-CM code (560.32) for fecal impaction was introduced, allowing for assessment of fecal impaction incidence. Study: Data were obtained from the National Emergency Department Sample records in which fecal impaction (ICD-9-CM code 560.32) was first listed as a diagnosis in 2011. Results: In 2011, there were 42,481 [95% confidence interval (CI), 39,908-45,054] fecal impaction ED visits, with an overall rate of 32 fecal impaction visits per 100,000 ED visits. Adjusted for inflation in 2014 dollars, the associated mean charge of a fecal impaction ED visit was 2943.02-130,010,772 (95% CI, 139,332,885). All charges were adjusted for inflation and reported in 2014 dollars. Late elders (85+ y) had the highest rate of fecal impaction ED visits, followed by early elders (65 to 84 y). Medicare was the primary payer for the greatest number of fecal impaction ED visits accounting for nearly two thirds of visit payments. Conclusion: This study reports previously unexplored statistics on the number, frequency, and associated charges of ED visits with a primary diagnosis of fecal impaction, a condition found most commonly among elders.6 page(s
Holocene shifts in the assembly of plant and animal communities implicate human impacts
No full textUnderstanding how ecological communities are organized and how they change through time is critical to predicting the effects of climate change¹. Recent work documenting the co-occurrence structure of modern communities found that most significant species pairs co-occur less frequently than would be expected by chance², ³. However, little is known about how co-occurrence structure changes through time. Here we evaluate changes in plant and animal community organization over geological time by quantifying the co-occurrence structure of 359,896 unique taxon pairs in 80 assemblages spanning the past 300 million years. Co-occurrences of most taxon pairs were statistically random, but a significant fraction were spatially aggregated or segregated. Aggregated pairs dominated from the Carboniferous period (307 million years ago) to the early Holocene epoch (11,700 years before present), when there was a pronounced shift to more segregated pairs, a trend that continues in modern assemblages. The shift began during the Holocene and coincided with increasing human population size⁴, ⁵ and the spread of agriculture in North America⁶, ⁷. Before the shift, an average of 64% of significant pairs were aggregated; after the shift, the average dropped to 37%. The organization of modern and late Holocene plant and animal assemblages differs fundamentally from that of assemblages over the past 300 million years that predate the large-scale impacts of humans. Our results suggest that the rules governing the assembly of communities have recently been changed by human activity. Corrigendum can be found in Nature, Volume 538, Issue 7626. p. 542. doi: http://dx.doi.org/10.1038/nature191044 page(s
Finding, appraising and interpreting the evidence of health IT
No full textEvidence-based health informatics can be described as a scientific approach to meeting the multiplicity of tasks involved in the development, implementation and sustainability of health information technologies (IT). The practice of evidence-based health informatics incorporates methods to help find, appraise and utilise research-based knowledge. The aim of this contribution is to describe the steps of finding, appraising and interpreting the evidence of health IT. It lists major sources of literature in the health field, and highlights a number of considerations for undertaking reviews, drawing on some key landmark reviews that have helped to shape the health informatics discipline. It also considers key issues highlighted by these reviews particularly in regard to the validity of findings, their generalisability and their impact on patient outcomes. The contribution also provides suggestions for tackling the challenge of potential publication bias, and how to deal with heterogeneous findings.12 page(s
Learning and teaching in Aboriginal and Torres Strait Islander education
No full textLearn from real voices and experiences. This book helps pre-service teachers prepare themselves for teaching Aboriginal and Torres Strait Islander students in urban, remote and rural primary and secondary schools. It also guides teachers to confidently include Aboriginal and Torres Strait Islander perspectives in their programming. The overall aim of this text is to ‘keep things local’, as working closely with the local community is absolutely crucial to successful teaching in Aboriginal and Torres Strait Islander education. This book balances educational theory with practical teaching strategies. Full of case studies, examples and a range of voices and personal stories from students, pre-service teachers, indigenous community members, it conveys the richness and diversity of Australian classrooms. Key Learning Features: Learning from Experience feature includes real life cases from teachers working with Aboriginal and Torres Strait Islander students. Video references link to a range of online resources, encouraging students to recognise the diversity of approaches to learning. Questions and activities appear at the end of chapter for readers to test their comprehension and discuss issues with other pre-service teachers. The authors provide detailed discussion on how to build empowering partnerships between schools and communities to help pre-service teachers become a part of local communities.First published as Teaching and Learning in Indigenous Education, 2008 (9780195561104). Second edition published as Teaching and Learning in Aboriginal Education, 2011 (9780195574593).259 page(s)3rd ed