697 research outputs found

    Key factors controlling the post-fire hydrological and erosive response at micro-plot scale in a recently burned Mediterranean forest

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    The impacts of wildfires on the hydrological and erosive response of forest ecosystems have been extensively studied worldwide. Nevertheless, few studies have measured post-fire runoff and erosion over large time scales in Mediterranean-climate type environments and even fewer studies considered the effects of pre-fire land management practices on post-fire hydrological and erosive processes. In a previous study in the Colmeal study area, Vieira et al. (2016) revealed that post-fire runoff and erosion may not follow the classic window of disturbance model, since the peak of post-fire response occurred in the second and third years after fire. This previous study also showed that pre-fire land management can substantially influence the post-fire response, since annual runoff and erosion were lower in pre-fire unplowed than plowed sites. In this follow-up work, a multiple regression model (MRM) analysis was performed to understand how several key factors influence the hydrological and erosive response of a burned Mediterranean forest, taking into account the wildfire; pre-fire land management practices (unplowed, downslope plowed, and contour plowed) and soil moisture conditions. Based on the results of the present study, post-fire runoff was largely explained by rainfall amounts and soil water repellency (SWR)-related variables, whereas erosion processes were better explained by rainfall intensity and ground cover variables. Fewer factors were found to control the hydrological response of plowed sites when compared to the unplowed site. Aside from rainfall intensity, which was the major factor controlling sediment losses, bare soil cover also seems to have been important for erosion processes at the unplowed site, whereas at the plowed sites stone cover was the second most relevant factor. Rainfall-related variables (rainfall and maximum 30-min rainfall intensity) were more important for explaining runoff and erosion under dry conditions than under wet conditions. The results of the MRM analysis are an important contribution to understand the dynamics of burned forest areas and should be considered when adapting hydrological and erosion models to post-fire environments.publishe

    Management oriented mathematical modelling of Ria Formosa (South Portugal)

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    1 - Ria Formosa is a large (c.a. 100 km2) mesotidal lagoon system included in a Natural Park, with large intertidal areas and several uses such as fisheries, aquaculture, tourism and nature conservation. Its watersheds cover an area of approximately 864 km2, with a hydrographic network of small and, mostly, ephemeral rivers. 2 - The Soil and Water Assessment Tool (SWAT model) has been applied to the catchments in order to simulate water discharges to Ria Formosa, providing forcing to a two-dimensional vertically integrated model, implemented with EcoDynamo – an object oriented modelling software – including hydrodynamics, water column, sediment biogeochemistry and growth models for some important benthic species. 3 - The main objectives of this work are to: (i) Analyse model performance in the light of available data; (ii) Evaluate the effects of dredging operations and changes in biomass densities of cultivated clams, on lagoon biogeochemistry and water quality. 4 - This work is part of a larger project where many possible management scenarios are being analysed following concerns expressed by the project end-users – Ria Formosa Natural Park authority. 5 - Results obtained so far suggest that bivalve rearing areas are probably being exploited close to their carrying capacity. Furthermore, it is apparent that some improvement on water quality could be achieved by reducing bivalve densities, without significant losses of harvest yields

    QED self-energy contribution to highly-excited atomic states

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    We present numerical values for the self-energy shifts predicted by QED (Quantum Electrodynamics) for hydrogenlike ions (nuclear charge 60Z11060 \le Z \le 110) with an electron in an n=3n=3, 4 or 5 level with high angular momentum (5/2j9/25/2\le j \le 9/2). Applications include predictions of precision transition energies and studies of the outer-shell structure of atoms and ions.Comment: 20 pages, 5 figure

    Sistemas de cultivo para as culturas de milho, feijão (Phaseolus vulgaris L.) e algodão em consórcio, no Estado de Sergipe.

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    Área de abrangênia, sistema de cultivo n.1 (milho x feijão), preparo do solo, adubação, plantio, época, cultivares, arranjo espacial, espaçamento e densidade do plantio, tratos culturais, tratos fitossanitários, colheita e beneficiamento, armazenamento, coeficientes técnicos, sistema de cultivo n.2, (milho x feijão x algodão) .bitstream/item/43933/1/CPATC-DOCUMENTOS-04-SISTEMAS-DE-CULTIVO-PARA-AS-CULTURAS-DE-MILHO-FEIJAO-E-ALGODAO-EM-CONSORCIO-N.pd

    Nebulized Heparin For Patients Under Mechanical Ventilation: An Individual Patient Data Meta-Analysis

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    Pulmonary coagulopathy is a characteristic feature of lung injury including ventilator-induced lung injury. The aim of this individual patient data meta-analysis is to assess the effects of nebulized anticoagulants on outcome of ventilated intensive care unit (ICU) patients. A systematic search of PubMed (1966–2014), Scopus, EMBASE, and Web of Science was conducted to identify relevant publications. Studies evaluating nebulization of anticoagulants in ventilated patients were screened for inclusion, and corresponding authors of included studies were contacted to provide individual patient data. The primary endpoint was the number of ventilator-free days and alive at day 28. Secondary endpoints included hospital mortality, ICU- and hospital-free days at day 28, and lung injury scores at day seven. We constructed a propensity score-matched cohort for comparisons between patients treated with nebulized anticoagulants and controls. Data from five studies (one randomized controlled trial, one open label study, and three studies using historical controls) were included in the meta-analysis, compassing 286 patients. In all studies unfractionated heparin was used as anticoagulant. The number of ventilator-free days and alive at day 28 was higher in patients treated with nebulized heparin compared to patients in the control group (14 [IQR 0–23] vs. 6 [IQR 0–22]), though the difference did not reach statistical significance (P = 0.459). The number of ICU-free days and alive at day 28 was significantly higher, and the lung injury scores at day seven were significantly lower in patients treated with nebulized heparin. In the propensity score-matched analysis, there were no differences in any of the endpoints. This individual patient data meta-analysis provides no convincing evidence for benefit of heparin nebulization in intubated and ventilated ICU patients. The small patient numbers and methodological shortcomings of included studies underline the need for high-quality well-powered randomized controlled trials

    Application of an endo-xylanase from Aspergillus japonicus in the fruit juice clarification and fruit peel waste hydrolysis.

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    The endo-xylanase from Aspergillus japonicus (UFMS 48.136) was purified in a single step using carboximethylcellulose chromatographic column and applied in fruit juice clarification process and fruit peel waste hydrolysis. This purification procedure resulted in 38.9-fold purification of endo-xylanase with 83.3% final yield. MALDITOF analysis confirmed the molecular mass of 32 kDa. The optimal purified endo-xylanase activity was at a range of pH from 5.0 to 6.0 and from 50 to 60 +-C, retaining more than 70% of its activity at all pH studied (3.0?8.0) for 24 h at room temperature. The A. japonicus endo-xylanolytic activity stimulation curve was assayed in the presence of different birchwood xylan concentrations (ranging from 0.02 to 0.5% w/v) and the endoxylanase activity presented a Vmax of 467.4 +- 30.38 μmol/min/mg, with a km of 2.59 +- 0.17 mg/mL, a kcat of 253.95 +- 16.51 s -1 and a kcat/km value of 98.05 +- 4.41 mL s -1 mg -1. The endo-xylanase was activated by Mn2þ (34.5%) and inhibited by Cu2þ (56.9%). The endo-xylanase was activated by β-mercaptoethanol, Triton X-100, Tween-20, Tween-80 and ferulic acid. In the clarification assay, endo-xylanase successfully clarified the juices of mango (51.11%), banana (9.99%) and tangerine (8.54%). Furthermore, the enzyme also hydrolysed all fruit peel wastes that were tested. In summary, A. japonicus endo-xylanase showed potential for applications in fruit juice clarification and in the treatment of fruit peel wastes, and it is a good candidate for the food industry due to its wide pH stability under acidic conditions

    Análise do ambiente interno da Embrapa Meio-Norte.

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    Infra-estrutura; Estrutura e evolução do quadro de pessoal; Clima organizacional; Recursos financeiros; Pontos fortes e pontos fracos; Análise da programação de pesquisa e desenvolvimento.bitstream/item/36291/1/Doc49.pd

    Impact of mothers' IPV-PTSD on their capacity to predict their child's emotional comprehension and its relationship to their child's psychopathology

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    Background: Previous studies demonstrated that when the violence-exposed child becomes a mother and interacts with her own child during early sensitive periods for social-emotional development, she may have difficulties providing sensitive responsiveness to the child's emotional communication. Such difficulties place the child's development of emotional comprehension (EC) and related self-regulation at risk. The aim of this study was to examine how mothers' interpersonal violence-related posttraumatic disorder (IPV-PTSD) would affect their children's EC and their own ability to predict their children's EC. We also investigated how mothers' predictive ability would correlate with child psychopathology. Methods: Sixty-one mother-child dyads (36 with IPV-PTSD) participated in this study. Children's (mean age = 7.0 years, SD = 1.1) EC was assessed with the Test of Emotion Comprehension (child TEC) and their psychopathology as reported by the mother was assessed with the Child Behaviour Checklist (CBCL) and as evaluated by a clinician using selected modules of the Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS). Mothers were measured for IPV-PTSD with the Clinician Administered PTSD Scale (CAPS) and for their capacity to predict their child's emotional comprehension (mother-responding-as-child TEC; mTEC). Results: We found no significant between-group differences in children's level of EC. Maternal PTSD was associated with lower scores on the mTEC, however. Reduced maternal scores on the mTEC were significantly associated with maternal report of increased aggressive child behaviour and with depression symptoms on the K-SADS. Further, scores on the mTEC interacted with maternal report of child aggression on child oppositional defiant disorder (ODD) symptoms on the K-SADS. Conclusion: These findings support that improving maternal emotional comprehension may help reduce child risk for psychiatric morbidity in this population

    Relación entre actividad física, composición corporal e imagen corporal en estudiantes universitarios

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    This work aims to analyze the relationship among body composition, body image and physical activity level in university students. The general description of the sample was made through the dependent variables (sex and age), and the identification of different body composition parameters (weight and height). The analysis of the body image was developed through its two components: perceptive (Figure Rating Scale-Stunkard, Sorenson y Schlusinger, 1983), and a subjective one (Body Shape Questionnare-Cooper, Taylor, Cooper, y Fairburn, 1987). The PA level was analyzed through the International Physical Activity Questionnaire (Craig et al., 2003). The sample (n = 400) was composed by university students, (49,5% women and 50,5% men) with a mean age of 30,64 (± 8.85 years). Results highlight that most students have a low level of PA, and there is an inverse relationship between body composition parameters and body image, that is, subjects who identify themselves with the larger silhouettes are those who are most dissatisfied and more concerned with their body image.Este trabajo tiene como objetivo principal analizar la relación entre la composición corporal, la imagen corporal y el nivel de actividad física de estudiantes universitarios. La descripción general de la muestra se realizó a través de las variables dependientes (sexo y edad), y por la identificación de diferentes parámetros de composición corporal (peso y altura). El análisis de la imagen corporal se desarrolla a través de sus dos vertientes, una perceptiva (Figure Rating Scale - Stunkard, Sorenson y Schlusinger, 1983), y otra subjetiva (Body Shape Questionnare - Cooper, Taylor, Cooper, y Fairburn, 1987). El nivel de actividad física se analizó a través del International Physical Activity Questionnaire (Craig et al., 2003). La muestra (n= 400) está constituida por estudiantes universitarios, de los cuales, el 49,5% son mujeres, y el 50,5% son hombres, con una media de edad de 30,64 (±8,85 años). Entre los resultados se puede destacar que la mayoría de los estudiantes tienen un nivel bajo de actividad física, y los sujetos que están más insatisfechos y más preocupados con su imagen corporal son los que se identifican con las siluetas más grandes
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