Ecological niche model comparison under different climate scenarios: a case study of Olea spp. in Asia

Ecological niche modeling (and the related species distribution modeling) has been used as a tool with which to assess potential impacts of climate change processes on geographic distributions of species. However, the factors introducing variation into niche modeling outcomes are not well understood: To this end, we used seven algorithms to develop models (Maxent, GARP, BIOCLIM, artificial neural networks, support‐vector machines, climate envelope, and environmental distance) to estimate the potential geographic distribution of olives (Olea europaea sensu lato, including Olea ferruginea) under two climatic data sets (current 2000 and future 2050). Five general circulation models and two representative concentration pathway scenarios were used as predictor variables in future projections of the geographic potential of this species; models were fit at global extents (10′ spatial resolution) but transferred and interpreted for a region of particular interest in Central Asia, which largely avoids problems with truncation of niche estimates. We found marked differences among approaches in predicted distributions and model performance, as well as in the future distributional pattern reconstructed, from one algorithm to another. These general approaches, when model‐to‐model variation is managed appropriately, appear promising in predicting the potential geographic distribution of O. europaea sensu lato and thus can be an effective tool in restoration and conservation planning for wild populations, as well as possible commercial plantations of this species

Outcome of the ‘Drip-and-Ship’ Paradigm among Patients with Acute Ischemic Stroke: Results of a Statewide Study

www.karger.com/cee This is an Open Access article licensed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License (www.karger.com/OA-license), applicable to the online version of the article only. Distribution for non-commercial purposes only.

A comparison of outcomes associated with carotid artery stent placement performed within and outside clinical trials in the United States

BackgroundA discrepancy between characteristics of patients treated with carotid angioplasty and stent placement (CAS) within and outside clinical trials, particularly characteristics with direct impact on clinical outcome, may limit generalization of clinical trial results. The objective of this study was to identify differences in demographic and clinical characteristics and outcomes related to CAS in patients treated within clinical trials and those treated outside clinical trials in a large national cohort.MethodsWe determined the frequency of CAS performed within and outside clinical trials and associated in-hospital outcomes using data from the Nationwide Inpatient Survey data files from 2005 to 2009. All the in-hospital outcomes were analyzed after adjusting for potential confounders using multivariate analysis.ResultsOf the 81,638 patients who underwent CAS, 16,078 (19.6%) underwent the procedure as part of a clinical trial. The mean age of the patients was significantly lower in patients treated with CAS as part of a clinical trial than those treated with CAS outside a clinical trial. The proportion of women and nonwhites was lower among patients treated with CAS as part of a clinical trial. The in-hospital mortality was two-fold higher among patients treated with CAS outside clinical trials (1.12% vs 0.53%; P = .0005). The rate of composite endpoint of stroke, cardiac events, and death was significantly higher among patients treated with CAS outside clinical trials (P = .02). After adjusting for age, gender, presence of renal failure, and hospital bed size, CAS performed as part of a clinical trial was associated with lower rates of in-hospital mortality (odds ratio, 0.467; 95% confidence interval, 0.290-0.751; P = .0017) and composite endpoint of stroke, cardiac events, and death (odds ratio, 0.752; 95% confidence interval, 0.594-0.952; P = .0180).ConclusionsOur results suggest that CAS procedures performed as part of clinical trials was associated with lower rates of in-hospital mortality and composite endpoint of stroke, cardiac events, and death in United States. These findings highlight the need for strategies that ensure appropriate adoption of CAS to ensure that the benefits observed in clinical trials can be replicated in general practice

Prospective Endovascular Treatment in Acute Ischemic Stroke Evaluating Non-Contrast Head CT versus CT Perfusion (PLEASE No CTP)

Background: Studies have shown a lack of agreement of computed tomography perfusion (CTP) in the selection of acute ischemic stroke (AIS) patients for endovascular treatment. Purpose: To demonstrate whether non-contrast computed tomography (CT) within 8 h of symptom onset is comparable to CTP imaging. Methods: Prospective study of consecutive anterior circulation AIS patients with a National Institute of Health Stroke Scale (NIHSS) score \u3e 7 presenting within 8 h of symptom onset with endovascular treatment. All patients had non-contrast CT, CT angiography, and CTP. The neuro-interventionalist was blinded to the results of the CTP and based the treatment decision using the Alberta Stroke Program Early CT score (ASPECTS). Baseline demographics, co-morbidities, and baseline NIHSS scores were collected. Outcomes were modified Rankin scale (mRS) score at discharge and in-hospital mortality. Good outcomes were defined as a mRS score of 0-2. Results: 283 AIS patients were screened for the trial, and 119 were enrolled. The remaining patients were excluded for: posterior circulation stroke, no CTP performed, could not obtain consent, and NIHSS score \u3c 7. Mean -NIHSS score at admission was 16.8 ± 3, and mean ASPECTS was 8.4 ± 1.4. There was no statistically significant correlation with CTP penumbra and good outcomes: 50 versus 47.8% with no penumbra present (p = 0.85). In patients without evidence of CTP penumbra, there was 22.5% mortality compared to 22.1% mortality in patients with a CTP penumbra. If ASPECTS ≥7, 64.6% had good outcome versus 13.3% if ASPECTS \u3c 7 (p \u3c 0.001). Patients with an ASPECTS ≥7 had 10% mortality versus 51.4% in patients with an ASPECTS \u3c 7 (p \u3c 0.001). Conclusions: CTP penumbra did not identify patients who would benefit from endovascular treatment when patients were selected with non-contrast CT ASPECTS ≥7. There is no correlation of CTP penumbra with good outcomes or mortality. Larger prospective trials are warranted to justify the use of CTP within 6 h of symptom onset