272 research outputs found

    Comparing Permeability of Matrix Cover Types for the Marsh Rice Rat (Oryzomys palustris)

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    Context Matrix land cover types differ in permeability to animals moving between habitat patches, and animals may actually move faster across lesssuitable areas. Marsh rice rats are wetland specialists whose dispersal crosses upland matrix. Objectives Our objectives were to (1) compare matrix permeability for the marsh rice rat among upland cover types, (2) compare permeability within versus outside perceptual range of the wetland, and (3) explore intrinsic and extrinsic features influencing matrix use and permeability. Methods We quantified permeability of grassland, crop field, and forest to the marsh rice rat during 2011–2012, by marking rats in wetlands and estimating the slope of capture rate versus distance (0–95 m) into the matrix. We also compared permeability within (0–15 m) and beyond the perceptual range of rice rats, and tested whether age, sex, time, water depth, rice rat abundance, and vegetation density influenced matrix use and permeability. Results Permeability was greater for soybean fields than grassland or forest but did not appear to differ within versus beyond rice rats’ perceptual range. Matrix capture rates were higher early in the study and in times and locations with thick ground vegetation and high rice rat abundance in the wetlands. Rice rats captured in the matrix were younger than those in wetland patches. Conclusions Our findings expand known matrix use by marsh rice rats, and support permeability being high in matrix types dissimilar to suitable habitat. Studying individual movements will help identify mechanisms underlying enhanced permeability in crop fields

    Conspecific Aggression by Beavers (Castor canadensis) in the Sangamon River Basin in Central Illinois: Correlates with Habitat, Age, Sex and Season

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    Conspecific aggression may play an important role in partitioning resources and maintaining territories among beavers (Castor canadensis), yet few studies have examined physical evidence of agonistic encounters. We trapped and examined pelts from 147 beavers harvested between 2006 and 2012 from the Sangamon River (n  =  96) and tributary streams (n  =  51) in central Illinois. We modeled the influence of sex, age class, season (predispersal or dispersal), and habitat (river or tributary stream) on the number of recent injuries caused by conspecifics. One-third (51/147) of beavers had ≥1 injury; of those, the median number of injuries was 2.0. Kits had fewer injuries than adults (βKit  =  −2.24 ± 0.63), but yearlings and subadults did not (βyearling  =  0.02 ± 0.38, βsubadult  =  −0.22 ± 0.48). Beavers on small streams had only one-quarter of the injuries recorded for beavers on the river (βStream  =  −1.34 ± 0.82). We failed to detect differences in injuries between the sexes. Our results suggest both sexes participate in territorial defense through physical confrontations and such encounters can be costly to both dispersing juveniles and resident adult

    Multiple Captures of White-footed Mice (Peromyscus leucopus): Evidence for Social Structure?

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    Multiple captures (34 double, 6 triple) in standard Sherman live traps accounted for 6.3% of 1355 captures of Peromyscus leucopus (white-footed mice) in forested habitat in southern Illinois, from Oct. 2004 through Oct. 2005. There was a significant positive relationship between both the number and the proportion of multiple captures and estimated monthly population size. Multiple captures were all intraspecific and occurred significantly more often from Nov. through Mar. when animals were not reproductively active, but this was confounded by seasonal changes in abundance. Age/gender distribution of animals in double captures did not differ from that expected from random pairing. We suggest that sociality and synchronous entry of two white-footed mice into traps were the primary determinants of double captures; sensitivity of traps may have been the primary factor in triple capture

    Measurement of mutual inductance from frequency dependence of impedance of AC coupled circuit using digital dual-phase lock-in amplifier

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    We present a simple method to determine the mutual inductance MM between two coils in a coupled AC circuit by using a digital dual-phase lock-in amplifier. The frequency dependence of the real and imaginary parts is measured as the coupling constant is changed. The mutual inductance MM decreases as the distance dd between the centers of coils is increased. We show that the coupling constant is proportional to dnd^{-n} with an exponent nn (\approx 3). This coupling is similar to that of two magnetic moments coupled through a dipole-dipole interaction.Comment: 9 pages, 10 figures, Fig.1 is corrected, figures in png files, short version is published in Am. J. Phys. 76, (2008) 12

    Metapopulation Viability of Swamp Rabbits in Southern Illinois: Potential Impacts of Habitat Change

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    Swamp rabbits (Sylvilagus aquaticus) in southern Illinois exist as a metapopulation due to fragmentation of the bottomland hardwood forests in which they live. This fragmentation makes their persistence in Illinois uncertain. We used population viability analysis (PVA) to estimate the probability of persistence of the swamp rabbit metapopulation in Illinois, using a habitat suitability map we created and life history parameters drawn from the literature. We varied the parameters used in our PVA from 50% to 150% of the initial value to compare their effects on extinction risk and to direct future management and research. We tested the effects of potential habitat loss and fragmentation by 1) removing patches individually and in groups from the analysis and by 2) adding 60, 120, and 180 m to the edge of all patches. We also tested the potential effect of dispersal corridors by increasing dispersal between connected patches. Under baseline conditions, the model suggests a 0% chance of quasiextinction (90% metapopulation decline) of swamp rabbits within 25 (or even 50) years. Changes in fecundity values and the effects of catastrophic flooding had the greatest effect on extinction risk, and changes in no other parameter yielded any appreciable impact. Removing the largest patches from the population increased the 25- year risk of extinction to 4%, whereas any other modifications to the habitat did not change the extinction risk. We suggest that managers focus on sustaining habitat quality, particularly upland habitats adjacent to occupied bottomland hardwood forests to improve the likelihood of swamp rabbit persistence in Illinois

    Differential diagnosis checklists reduce diagnostic error differentially: a randomized experiment

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    Introduction Wrong and missed diagnoses contribute substantially to medical error. Can a prompt to generate alternative diagnoses (prompt) or a differential diagnosis checklist (DDXC) increase diagnostic accuracy? How do these interventions affect the diagnostic process and self-monitoring? Methods Advanced medical students (N = 90) were randomly assigned to one of four conditions to complete six computer-based patient cases: group 1 (prompt) was instructed to write down all diagnoses they considered while acquiring diagnostic test results and to finally rank them. Groups 2 and 3 received the same instruction plus a list of 17 differential diagnoses for the chief complaint of the patient. For half of the cases, the DDXC contained the correct diagnosis (DDXC+), and for the other half, it did not (DDXC−; counterbalanced). Group 4 (control) was only instructed to indicate their final diagnosis. Mixed-effects models were used to analyse results. Results Students using a DDXC that contained the correct diagnosis had better diagnostic accuracy, mean (standard deviation), 0.75 (0.44), compared to controls without a checklist, 0.49 (0.50), P < 0.001, but those using a DDXC that did not contain the correct diagnosis did slightly worse, 0.43 (0.50), P = 0.602. The number and relevance of diagnostic tests acquired were not affected by condition, nor was self-monitoring. However, participants spent more time on a case in the DDXC−, 4:20 min (2:36), P ≤ 0.001, and DDXC+ condition, 3:52 min (2:09), than in the control condition, 2:59 min (1:44), P ≤ 0.001. Discussion Being provided a list of possible diagnoses improves diagnostic accuracy compared with a prompt to create a differential diagnosis list, if the provided list contains the correct diagnosis. However, being provided a diagnosis list without the correct diagnosis did not improve and might have slightly reduced diagnostic accuracy. Interventions neither affected information gathering nor self-monitoring

    Exploring objective measures for assessing team performance in healthcare: an interview study.

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    INTRODUCTION Effective teamwork plays a critical role in achieving high-performance outcomes in healthcare. Consequently, conducting a comprehensive assessment of team performance is essential for providing meaningful feedback during team trainings and enabling comparisons in scientific studies. However, traditional methods like self-reports or behavior observations have limitations such as susceptibility to bias or being resource consuming. To overcome these limitations and gain a more comprehensive understanding of team processes and performance, the assessment of objective measures, such as physiological parameters, can be valuable. These objective measures can complement traditional methods and provide a more holistic view of team performance. The aim of this study was to explore the potential of the use of objective measures for evaluating team performance for research and training purposes. For this, experts in the field of research and medical simulation training were interviewed to gather their opinions, ideas, and concerns regarding this novel approach. METHODS A total of 34 medical and research experts participated in this exploratory qualitative study, engaging in semi-structured interviews. During the interview, experts were asked for (a) their opinion on measuring team performance with objective measures, (b) their ideas concerning potential objective measures suitable for measuring team performance of healthcare teams, and (c) their concerns regarding the use of objective measures for evaluating team performance. During data analysis responses were categorized per question. RESULTS The findings from the 34 interviews revealed a predominantly positive reception of the idea of utilizing objective measures for evaluating team performance. However, the experts reported limited experience in actively incorporating objective measures into their training and research. Nevertheless, they identified various potential objective measures, including acoustical, visual, physiological, and endocrinological measures and a time layer. Concerns were raised regarding feasibility, complexity, cost, and privacy issues associated with the use of objective measures. DISCUSSION The study highlights the opportunities and challenges associated with employing objective measures to assess healthcare team performance. It particularly emphasizes the concerns expressed by medical simulation experts and team researchers, providing valuable insights for developers, trainers, researchers, and healthcare professionals involved in the design, planning or utilization of objective measures in team training or research

    Barriers to seeking emergency care during the COVID-19 pandemic may lead to higher morbidity and mortality – a retrospective study from a Swiss university hospital

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    AIMS OF THE STUDY While COVID-19 significantly overburdens emergency rooms (ERs) and hospitals in affected areas, ERs elsewhere report a marked decrease in patient numbers. This study aimed to investigate the assumption that patients with urgent problems currently avoid the ER. METHODS Electronic health records from the ER of a large Swiss university hospital were extracted for three periods: first, the awareness phase (ap) from the publication of the national government’s initiative “How to protect ourselves” on 1 March 2020 to the lockdown of the country on 16 March; second, the mitigation phase (mp) from 16–30 March; finally, patients presenting in March 2019 were used as a control group. We compared parameters including a critical illness as the discharge diagnosis (e.g., myocardial infarction, stroke, sepsis and ER death) using logistic and linear regression, as well as 15-day bootstrapped means and 95% confidence intervals for the control group. RESULTS In the three periods, a total of 7143 patients were treated. We found a 24.9% (42.5%) significant decline in the number of patients presenting during the ap (mp). Patients presenting during the mp were more likely to be critically ill. There was an increase of 233% and 367% (ap and mp, respectively) of ER deaths (none related to COVID-19) compared to the control period. Apart from polytrauma (increase of 5% in the mp), all other critical illnesses as discharge diagnosis showed a lower incidence in descriptive analysis. Significantly more patients died in the ER in both the ap and mp. CONCLUSIONS Barriers to seeking emergency care during COVID-19 pandemic may lead to higher morbidity and mortality. Healthcare authorities and hospitals must ensure low barriers to treatment and business as usual for all patients
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