8,115 research outputs found

    Estimating Queen Conch (Strombus gigas) home ranges using acoustic telemetry: implications for the design of marine fishery reserves

    Get PDF
    Marine reserves (MRs) may function as a vital tool in the conservation and management of marine resources if source populations are managed for the benefit of those downstream. Consequently, it is critical to evaluate the home range of marine animals to ensure that MRs are large enough to protect source populations. We used acoustic telemetry to study movements of adult queen conch (Strombus gigas) within aggregations at two sites in the Florida Keys from June 1997 through July 1998. A total of 68 conch were tagged and tracked for up to one year. Latitude and longitude of each conch were recorded biweekly and data used to estimate the minimum speed, degree of site fidelity, and home range of each animal. Conch showed significantly greater displacement/ time during the summer. There were no significant differences in movement rate, site fidelity, or size of home range between males and females. Mean home range was 5.98 ha. Based on estimated home ranges of the aggregations, the size and location of the existing reserves at these two sites were inadequate to protect the conch aggregations should the fishery reopen

    Flexible density surface estimation for spatially explicit capture-recapture surveys

    Get PDF
    1. Existing spatially explicit capture-recapture (SECR) software does not have the ability to fit flexible nonparametric models of animal density. 2. We describe and implement in the R package secrgam, a flexible method for estimating density surfaces from SECR data, using regression splines. 3. Package secrgam is an extension of package secr to implement some models available in the generalised additive model package mvcv. It accommodates density models that are arbitrarily flexible functions of spatially- and temporally-referenced variables. This includes one-dimensional and multi-dimensional smooths of covariates and smooths with interactions. The shape and smoothness of the fitted density surfaces is data-driven and can be determined using AIC or similar criteria. We illustrate use of the package by estimating the density surface from a simulated camera trap survey of leopards. 4. Package secrgam provides a flexible tool for species distribution modelling using SECR data.Postprin

    Impaired renal function affects clinical outcomes and management of patients with heart failure.

    Get PDF
    AIMS: Inpatients with heart failure and renal impairment have poor outcomes and variable quality of care. We investigate treatment practice and outcomes in an unselected real-world cohort using historical creatinine measurements. METHODS AND RESULTS: Admissions between 1/4/2013 and 30/4/2015 diagnosed at discharge with heart failure were retrospectively analysed. Stages of chronic kidney disease (CKD) and acute kidney injury (AKI) were calculated from creatinine at discharge and 3-12 months before admission. We identified 1056 admissions of 851 patients (mean age 76 years, 56% Caucasian, 36% with diabetes mellitus, 54% with ischaemic heart disease, and 57% with valvular heart disease). CKD was common; 36%-Stage 3a/b, 11%-Stage 4/5; patients were older, more often diabetic, with higher potassium, lower haemoglobin, and more oedema but similar prevalence of left ventricular systolic dysfunction (LVSD) compared patients with Stages 0-2. AKI was present in 17.0% (10.4%-Stage 1, 3.7%-Stage 2, and 2.9%-Stage 3); these had higher potassium and lower haemoglobin than patients with no AKI. Length of stay was longer in Stage 4/5 CKD [11 days; P = 0.008] and AKI [13 days; P = 0.006]. Mortality was higher with Stage 4/5 CKD (13.8% compared with 7.7% for Stages 0-2 CKD (P = 0.036)] and increased with AKI (5%-no AKI, 20.9%-Stage 1, 35.9%-Stage 2, and 48.4%-Stage 3; P < 0.001). Adjusted for age, diabetes, and LVSD, both AKI and Stage 4/5 CKD were independent predictors of in-hospital mortality. In survivors with LVSD, the discharge prescription of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers decreased with progressive CKD, [84%-no-mild, 59%-moderate, and 36%-severe CKD; P < 0.001]; this was not purely explained by hyperkalaemia. CONCLUSIONS: Inpatients with heart failure and renal impairment, acute and chronic, failed to receive recommended therapy and had poor outcomes

    Adherence Behavior in Subjects on Hemodialysis Is Not a Clear Predictor of Posttransplantation Adherence

    Get PDF
    © 2019 The Authors. Published by Elsevier Inc. on behalf of the International Society of Nephrology. This is an openaccess article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Introduction: Nonadherence is common in both hemodialysis (HD) and kidney transplant recipients and is a major risk factor for poor clinical outcomes. This retrospective study explored whether nonadherent HD patients become nonadherent transplant recipients. Methods: Data were collected for 88 patients from the electronic patient system at a subregional renal unit about adherence to HD regimens in the 6 months before transplantation, and for 1 year posttransplantation following return transfer to the posttransplantation clinic from the transplanting center. Pretransplantation definitions of nonadherence included whether the patients: on average, shortened their dialysis prescription by >10 minutes; shortened it by >15 minutes; missed 2 or more HD sessions; and had mean serum phosphate levels >1.8mmol/l. Posttransplantation definitions of nonadherence included mean tacrolimus levels outside 5 to 10 ng/ml; and missed 1 or more posttransplantation clinic appointments. Results: Nonadherence ranged from 25% to 42% pretransplantation and from 15.9% to 22.7% posttransplantation, depending on how it was operationalized. There was little relationship between pretransplantation data and posttransplantation adherence, with the exception of a significant relationship between pretransplantation phosphate and posttransplantation clinic attendance. Patients who had missed 1 or more transplant clinic appointments had higher mean pretransplantation phosphate levels. Nonadherent patients with high phosphate levels pretransplantation and missed clinic appointments posttransplantation were significantly younger. Conclusion: Our findings provide little support for the likelihood of a strong direct relationship between pre and posttransplantation behaviors. The findings require confirmation and further research to assess whether interventions in relation to pretransplantation adherence may enhance adherence posttransplantation and improve outcomes.Peer reviewedProo
    corecore