14 research outputs found

    Deciphering the impact of uncertainty on the accuracy of large wildfire spread simulations

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    Predicting wildfire spread is a challenging task fraught with uncertainties. ‘Perfect’ predictions are unfeasible since uncertainties will always be present. Improving fire spread predictions is important to reduce its negative environmental impacts. Here, we propose to understand, characterize, and quantify the impact of uncertainty in the accuracy of fire spread predictions for very large wildfires. We frame this work from the perspective of the major problems commonly faced by fire model users, namely the necessity of accounting for uncertainty in input data to produce reliable and useful fire spread predictions. Uncertainty in input variables was propagated throughout the modeling framework and its impact was evaluated by estimating the spatial discrepancy between simulated and satellite-observed fire progression data, for eight very large wildfires in Portugal. Results showed that uncertainties in wind speed and direction, fuel model assignment and typology, location and timing of ignitions, had a major impact on prediction accuracy.We argue that uncertainties in these variables should be integrated in future fire spread simulation approaches, and provide the necessary data for any firemodel user to do soinfo:eu-repo/semantics/publishedVersio

    Assessment of the burden of caregiving for patients with chronic obstructive pulmonary disease

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    AbstractObjectiveTo determine the effect of chronic obstructive pulmonary disease (COPD) on the quality of life of caregivers.Design and methodsA cross-sectional study was carried out with forty-two COPD patients and their primary caregivers. Patients were assessed with the medical outcome survey short form (SF-36), the physical and mental component summary (PCS and MCS), Saint George's respiratory questionnaire (SGRQ), 6-min walking test, and spirometric and blood gas measurements. Caregivers were assessed using the medical outcome survey short form (SF-36), the physical and mental component summary (PCS and MCS), the 5-point Likert scale for measuring caregiver/patient relationships and the caregiver burden scale (CB scale).ResultsThe majority of caregivers were female (85.3%), married (59%) and had low levels of income and schooling. The mean age was 51.6±16 years. Mean caregiver PCS and MCS scores were 45.9±10 and 46±12, while the mean total burden score was 1.79±0.6. The regression analysis showed caregiver/patient relationship quality, caregiver MCS scores and patient PCS scores to be important predictors of burden and explained 63% of the variance.ConclusionsCOPD causes a significant impact on the quality of life of caregivers. The two most important predictors of COPD burden are the relationship between caregivers and patients and caregiver MCS scores

    Biological activity of Pouteria sapota leaf extract on post-embryonic development of blowfly Chrysomya putoria (Wiedemann, 1818) (Calliphoridae)

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    Chemical insecticides have been the main way to control synanthropic flies of medical and veterinary importance; however, residuals of these products have become a factor impacting on the environment, as well as the potential toxicological that they may cause damage to humans and domestic animals. Phytochemical screening carried out with the aqueous crude extract of Pouteria sapota (Jacq.) H.E. Moore & Stearn, Sapotaceae, leaves showed that coumarins, reducing sugars, flavonoids and cyanogenic glycosides were its most abundant metabolites. This study evaluated the activity of the crude aqueous extract of this plant on the post-embryonic development of Chrysomya putoria. Larvae treated with 5, 10 and 25% extract showed a decrease in the pupal period and in the newly-hatched larvae to adult period when compared to the control groups. Larvae from the 25% extract group were the lightest (45.8 mg) when compared with the control group (46.5 mg). The larval and newly-hatched larvae to adult stages were more sensitive to the leaf extract from P. sapota (5%) and the treated flies showed the low viability (47.5 and 45.5% respectively). The results demonstrated that topic treatment with P. sapota could alter C. putoriapost embryonic development
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