935 resultados para Drought Response Index


Relevância:

80.00% 80.00%

Publicador:

Resumo:

En la presente tesis se desarrolla una metodología y una herramienta informática que permite abordar de forma eficaz y eficiente problemas de gestión de los recursos intervinientes en emergencias. Se posibilita, a través de indicadores innovadores como el Índice de Respuesta Operativa (I.RO.), una evaluación correcta del riesgo real en función de los medios disponibles y de su probabilidad de colapso, permitiendo desarrollar una optimización de la utilización estos medios tanto en el presente como en escenarios futuros. Para su realización se describen inicialmente los principales actores que intervienen en las emergencias evaluándolos y mostrando las sinergias existentes. Se define y analiza, a través de sistemas complejos socialmente inteligentes (SCSI) el “ciclo de global de las emergencias”: planificación, prevención, detección, intervención, rehabilitación y el tratamiento informativo de la crisis. Del mismo modo se definen los distintos escenarios donde se interviene y cómo se puede prever su evolución. Para ello se establecen unas tipologías de siniestros y se identifican las similitudes o diferencias entre ellos. También se describe y modela el problema de la toma de decisiones a nivel de planificación operativa, desde la localización de instalaciones, tipologías de parques de bomberos, etc. Para demostrar la viabilidad de la metodología desarrollada se realiza su aplicación al territorio de la Comunidad Autónoma de Madrid obteniendo resultados satisfactorios a partir de los datos existentes. Es un estudio totalmente innovador y de amplia repercusión no solo en la gestión de las emergencias sino también en otros campos tales como el de estrategia militar, comercial, de gestión de organizaciones, etc. ABSTRACT This Phd Thesis presents a method and software tool that allows facing, in an efficient and effective manner, the resources involved in emergencies. It enables a correct assessment of the real risk as a function of the available resources and its collapse likelihood. This is achieved by mean of some novel indexes such as the Operative Response Index. Therefore, it allows a current and future optimization of the use of available resources. First, it describes the main factors affecting emergencies, assessing them and showing existing synergies. Then, it defines and analyse through complex systems socially intelligent (CSSI) the overall emergency cycle: planning, prevention, detection, intervention, rehabilitation and informative crisis coverage. Similarly, it defines the scenarios of intervention and how to forecast their progress. To this end, some typologies of disasters are defined, identifying commonalities. Moreover, it also describes and model decision-making issues at operationalplanning level, such as the location of facilities, typologies of fire stations, etc. In order to prove the feasibility of the developed methodology, it is applied to the Comunidad Autónoma de Madrid, getting successful results from the existing data. This Phd Thesis is an innovative study with far reaching impact, not only in emergency management but also in other fields such as the military, business strategy, organizational management, etc.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The chemical changes in clay minerals has been widely studied in order to improve its properties for use in various applications. However kaolinite has strong hydrogen bonds between their adjacent layers hindering the process changes in its structure. With the objective to facilitate the process of intercalation monobasic potassium phosphate, bibasic potassium phosphate and potassium acetate we was performed on kaolinite heat treatment at 600 °C and activated acidic with phosphoric acid and 5 to 10 mol L-1. The samples they were characterized by energy dispersive spectroscopy (EDS), X-Ray Diffraction (XRD), Infrared Spectroscopy Fourier Transform (FTIR) and Thermogravimetric Analysis (TG) and Differential Thermal Analysis (DTG) and the superficial and textural changes the samples with heat treatment and acid activation they were characterized by scanning electron microscopy (SEM) and Textural Analysis of Adsorption/desorption N2. With the help of the techniques found that, the heat treatment becomes more susceptible to acid activation kaolinite making the samples with two treatments show larger amounts of phosphorus. It was also found that bibasic potassium phosphate binds more strongly the structure of kaolinite by having a structure with two-coordinating oxygens and intercalation with potassium acetate in acid-activated kaolin increases the interlayer distance of the kaolinite and the intercalation occurs with higher response index (RI) for samples with acid activation to 5 mol /L.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Dissertação (mestrado)—Universidade de Brasília, Departamento de Botânica, Programa de Pós-Graduação em Botânica, 2016.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Tree populations at the rear edge of species distribution are sensitive to climate stress and drought. However, growth responses of these tree populations to those stressors may vary along climatic gradients. To analyze growth responses to climate and drought using dendrochronology in rear-edge Pinus nigra populations located along an aridity gradient. Tree-ring width chronologies were built for the twentieth century and related to monthly climatic variables, a drought index (Standardized Precipitation-Evapotranspiration Index), and two atmospheric circulation patterns (North Atlantic and Western Mediterranean Oscillations). Growth was enhanced by wet and cold previous autumns and warm late winters before tree-ring formation. The influence of the previous year conditions on growth increased during the past century. Growth was significantly related to North Atlantic and Western Mediterranean Oscillations in two out of five sites. The strongest responses of growth to the drought index were observed in the most xeric sites. Dry conditions before tree-ring formation constrain growth in rear-edge P. nigra populations. The comparisons of climate-growth responses along aridity gradients allow characterizing the sensitivity of relict stands to climate warming.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Screening for drought resistance of rainfed lowland rice using drought score (leaf death) as a selection index has a long history of use in breeding programs. Genotypic variation for drought score during the vegetative stage in two dry season screens was examined among 128 recombinant inbred lines from four biparental crosses. The genotypic variation detected for drought score in the dry season was used to examine the reliability of the dry season screening method to estimate relative grain yield of genotypes under different types of drought stress in the wet season. Large genotypic variation for drought score existed in two experiments (A and B). However, there was no relationship between the drought scores of genotypes determined in these two experiments. Different patterns of development and severity of drought stress in these two experiments, i.e. slow development and mild plant water deficit in experiment A and fast development and severe plant water deficit in experiment B, were identified as the major factors contributing to the genotypes responding differently. Larger drought score in the dry season experiments was associated with lower grain yield under specific drought stress conditions in the wet season, but the association was weak to moderate and significant only in particular drought conditions. In most cases, a significant phenotypic and moderate genetic correlation between drought score in the dry season and grain yield in the wet season existed only when both drought score and grain yield of genotypes were affected by similar patterns and severity of drought stress in their respective experimental environments. The dry season environments used to measure genotypic variation for drought score should be managed to correspond to relevant types of drought environment that are frequent in the wet season. The efficiency of using the drought score as an indirect selection criterion for improving grain yield for drought conditions was lower than the direct selection for grain yield, and hence wet season screening with grain yield as a selection criterion would be more efficient. However, using drought score as a selection index, a larger number of genotypes can be evaluated than for wet season grain yield. Therefore, it is possible to apply higher selection intensities using the drought score system, and the selected lines can be further tested for grain yield in the wet season. (C) 2004 Elsevier B.V. All rights reserved.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Chiral metamaterials have recently gained attention due to their applicability in developing polarization devices and in the detection of chiral molecules. A common approach towards fabricating plasmonic chiral nanostructures has been decorating metallic nanoparticles on dielectric chiral scaffolds, such as a helix. This resulted in the generation of a large chiro-optical response over a wide range of the electromagnetic spectrum. It has been shown previously that the optical tunability of these chiral metamaterials depends on the geometrical aspects of the overall structure, as well as the nature of the plasmonic constituents. In this study, we have investigated the role of the underlying dielectric scaffold with numerical simulations, and experimentally demonstrated that it is possible to enhance and engineer their chiro-plasmonic response significantly by choosing dielectric scaffolds of appropriate materials.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Background: Ivacaftor has shown a clinical benefit in patients with cystic fibrosis who have the G551D-CFTR mutation and reduced lung function. Lung clearance index (LCI) using multiple-breath washout might be an alternative to and more sensitive method than forced expiratory volume in 1 s (FEV1) to assess treatment response in the growing number of children and young adults with cystic fibrosis who have normal spirometry. The aim of the study was to assess the treatment effects of ivacaftor on LCI in patients with cystic fibrosis, a G551D-CFTR mutation, and an FEV1 >90% predicted. Methods: This phase 2, multicentre, placebo-controlled, double-blind 2×2 crossover study of ivacaftor treatment was conducted in patients with cystic fibrosis, at least one G551D-CFTR allele, and an FEV1 >90% predicted. Patients also had to have an LCI higher than 7·4 at screening, age of 6 years or older, and a weight higher than or equal to 15 kg. Eligible patients were randomly allocated to receive one of two treatment sequences (placebo first followed by ivacaftor 150 mg twice daily [sequence 1] or ivacaftor 150 mg twice daily first followed by placebo [sequence 2]) of 28 days' treatment in each period, with a 28-day washout between the two treatment periods. Randomisation (ratio 1:1) was done with block sizes of 4, and all site personnel including the investigator, the study monitor, and the Vertex study team were masked to treatment assignment. The primary outcome measure was change from baseline in LCI. The study is registered at ClinicalTrials.gov, NCT01262352. Findings: Between February and November, 2011, 21 patients were enrolled, of which 11 were assigned to the sequence 1 group, and 10 to the sequence 2 group. 20 of these patients received treatment and 17 completed the trial (eight in sequence 1 group and 9 in sequence 2 group). Treatment with ivacaftor led to significant improvements compared with placebo in LCI (difference between groups in the average of mean changes from baseline at days 15 and 29 was -2·16 [95% CI -2·88 to -1·44]; p<0·0001). Adverse events experienced by study participants were similar between treatment groups; at least one adverse event was reported by 15 (79%) of 19 patients who received placebo and 13 (72%) of 18 patients who received ivacaftor. No deaths occurred during study period. Interpretation: In patients with cystic fibrosis aged 6 years or older who have at least one G551D-CFTR allele, ivacaftor led to improvements in LCI. LCI might be a more sensitive alternative to FEV1 in detecting response to intervention in these patients with mild lung disease. Funding: Vertex Pharmaceuticals Incorporated. © 2013 Elsevier Ltd.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Context: Variation in photosynthetic activity of trees induced by climatic stress can be effectively evaluated using remote sensing data. Although adverse effects of climate on temperate forests have been subjected to increased scrutiny, the suitability of remote sensing imagery for identification of drought stress in such forests has not been explored fully. Aim: To evaluate the sensitivity of MODIS-based vegetation index to heat and drought stress in temperate forests, and explore the differences in stress response of oaks and beech. Methods: We identified 8 oak and 13 beech pure and mature stands, each covering between 4 and 13 MODIS pixels. For each pixel, we extracted a time series of MODIS NDVI from 2000 to 2010. We identified all sequences of continuous unseasonal NDVI decline to be used as the response variable indicative of environmental stress. Neural Networks-based regression modelling was then applied to identify the climatic variables that best explain observed NDVI declines. Results: Tested variables explained 84–97% of the variation in NDVI, whilst air temperature-related climate extremes were found to be the most influential. Beech showed a linear response to the most influential climatic predictors, while oak responded in a unimodal pattern suggesting a better coping mechanism. Conclusions: MODIS NDVI has proved sufficiently sensitive as a stand-level indicator of climatic stress acting upon temperate broadleaf forests, leading to its potential use in predicting drought stress from meteorological observations and improving parameterisation of forest stress indices.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Epigenetic modification of the genome via cytosine methylation is a dynamic process that responds to changes in the growing environment. This modification can also be heritable. The combination of both properties means that there is the potential for the life experiences of the parental generation to modify the methylation profiles of their offspring and so potentially to ‘pre-condition’ them to better accommodate abiotic conditions encountered by their parents. We recently identified high vapor pressure deficit (vpd)-induced DNA methylation at two gene loci in the stomatal development pathway and an associated reduction in leaf stomatal frequency.1 Here, we test whether this epigenetic modification pre-conditioned parents and their offspring to the more severe water stress of periodic drought. We found that three generations of high vpd-grown plants were better able to withstand periodic drought stress over two generations. This resistance was not directly associated with de novo methylation of the target stomata genes, but was associated with the cmt3 mutant’s inability to maintain asymmetric sequence context methylation. If our finding applies widely, it could have significant implications for evolutionary biology and breeding for stressful environments.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Remotely sensed rainfall is increasingly being used to manage climate-related risk in gauge sparse regions. Applications based on such data must make maximal use of the skill of the methodology in order to avoid doing harm by providing misleading information. This is especially challenging in regions, such as Africa, which lack gauge data for validation. In this study, we show how calibrated ensembles of equally likely rainfall can be used to infer uncertainty in remotely sensed rainfall estimates, and subsequently in assessment of drought. We illustrate the methodology through a case study of weather index insurance (WII) in Zambia. Unlike traditional insurance, which compensates proven agricultural losses, WII pays out in the event that a weather index is breached. As remotely sensed rainfall is used to extend WII schemes to large numbers of farmers, it is crucial to ensure that the indices being insured are skillful representations of local environmental conditions. In our study we drive a land surface model with rainfall ensembles, in order to demonstrate how aggregation of rainfall estimates in space and time results in a clearer link with soil moisture, and hence a truer representation of agricultural drought. Although our study focuses on agricultural insurance, the methodological principles for application design are widely applicable in Africa and elsewhere.