969 resultados para intervention modelling experiments
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Remote sensing using airborne imaging spectroscopy (AIS) is known to retrieve fundamental optical properties of ecosystems. However, the value of these properties for predicting plant species distribution remains unclear. Here, we assess whether such data can add value to topographic variables for predicting plant distributions in French and Swiss alpine grasslands. We fitted statistical models with high spectral and spatial resolution reflectance data and tested four optical indices sensitive to leaf chlorophyll content, leaf water content and leaf area index. We found moderate added-value of AIS data for predicting alpine plant species distribution. Contrary to expectations, differences between species distribution models (SDMs) were not linked to their local abundance or phylogenetic/functional similarity. Moreover, spectral signatures of species were found to be partly site-specific. We discuss current limits of AIS-based SDMs, highlighting issues of scale and informational content of AIS data.
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We develop a real option model of the irreversible native grassland conversion decision. Upon plowing, native grassland can be followed by either a permanent cropping system or a system in which land is put under cropping (respectively, grazing) whenever crop prices are high (respectively, low). Switching costs are incurred upon alternating between cropping and grazing. The effects of risk intervention in the form of crop insurance subsidies are studied, as are the effects of cropping innovations that reduce switching costs. We calibrate the model by using cropping return data for South Central North Dakota from 1989 to 2012. Simulations show that a risk intervention that offsets 20% of a cropping return shortfall increases the sod-busting cost threshold, below which native sod will be busted, by 41% (or $43.7/acre). Omitting cropping return risk across time underestimates this sod-busting cost threshold by 23% (or $24.35/acre), and hence underestimates the native sod conversion caused by crop production.
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Introduction Le rythmes circadiens influencent différents paramètres de la physiologie et de la physiopathologie cardiovasculaire. Récemment, une relation entre la taille d'un infarctus et l'heure du jour à laquelle il se produit a été suggérée dans des modèles expérimentaux d'infarctus du myocarde. Le but de cette étude a été de déterminer si les rythmes circadiens pouvaient influencer la gravité d'un infarctus en terme de taille et de mortalité chez les patients hospitalisés pour un infarctus du myocarde avec sus-décalage du segment ST (STEMI) ayant bénéficié d'une intervention coronarienne percutanée primaire (ICPP). Méthode Chez 353 patients consécutifs admis avec un STEMI et traités par ICPP, l'heure à la survenue des symptômes, le pic de créatine kinase (reflet de la taille d'un infarctus) et le suivi à 30 jours ont été collectés. Les patients ont été répartis en 4 groupes en fonction de l'heure de survenue de leurs symptômes (00 :00 - 05h59, 06:00 - 11 59 12 00-17h59 et 18h00-23h59). Résultats Aucune différence statistiquement significative n'a été retrouvée entre les différents groupes en ce qui concerne les caractéristiques des patients ou de leur prise en charge. Après analyse multivariée, nous avons mis en évidence une différence statistiquement significative entre les pics de créatine kinase chez les patients avec survenue des symptômes entre 00 :00 et 05:59, qui étaient plus élevés que les pics de créatine kinase chez les patients avec survenue des symptômes à tout autre moment de la journée (augmentation moyenne de 38,4%, ρ <0.05). A 30 jours, la mortalité des patients avec survenue des symptômes entre 00 :00 et 05:59 était également significativement plus élevé que celle des patients avec survenue à tout autre moment de la journée (p <0.05). Conclusion Notre étude démontre une corrélation indépendante entre la taille d'un infarctus STEMI traité par ICPP et le moment de la journée où les symptômes apparaissent. Ces résultats suggèrent que ce moment devrait être un paramètre important à prendre en compte pour évaluer le pronostic des patients.
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OBJECTIVES: Early intervention and preventive strategies have become major targets of research and service development in psychiatry over the last few years. Compared to schizophrenia, bipolar disorder (BD) has received limited attention in this regard. In this paper, we review the available literature in order to explore the public health significance of BD and the extent to which this may justify the development of early intervention strategies for this disorder. METHODS: The main computerized psychiatric literature databases were accessed. This included Medline and PsychInfo, using the following keywords: bipolar, early intervention, staging model, burden, caregiver, public health, and manic depression. RESULTS: BD is often recurrent and has an impact that goes well beyond symptomatic pathology. The burden it incurs is linked not only to its cardinal clinical features, but also to cognitive dysfunction, poor functional outcome, poor physical health, high rate of comorbidities, and suicide. At a societal level, BD induces enormous direct and indirect costs and has a major impact on caregivers. The available literature reveals a usually long delay between illness onset and the start of treatment, and the absence of specific guidelines for the treatment of the early phase of BD. CONCLUSIONS: Considering the major impact of BD on patients and society, there is an urgent need for the development of early intervention strategies aimed at earlier detection and more specific treatment of the early phase of the disorder.
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The outcome after primary percutaneous coronary intervention (pPCI) for ST-elevation myocardial infarction (STEMI) is strongly affected by time delays. In this study, we sought to identify the impact of specific socioeconomic factors on time delays, subsequent STEMI management and outcomes in STEMI patients undergoing pPCI, who came from a well-defined region of the French part of Switzerland. A total of 402 consecutive patients undergoing pPCI for STEMI in a large tertiary hospital were retrospectively studied. Symptom-to-first-medical-contact time was analysed for the following socioeconomic factors: level of education, origin and marital status. Main exclusion criteria were: time delay beyond 12 hours, previous treatment with fibrinolytic agents or patients immediately referred for coronary artery bypass graft surgery. Therefore, 222 patients were finally included. At 1 year, there was no difference in mortality between the different socioeconomic groups. Furthermore, there was no difference in management characteristics between them. Symptom-to-first-medical-contact time was significantly longer for patients with a low level of education, Swiss citizens and unmarried patients, with median differences of 23 minutes, 18 minutes and 13 minutes, respectively (p <0.05). Nevertheless, no difference was found regarding in-hospital management and clinical outcome. This study demonstrates that symptom-to-first-medical-contact time is longer amongst people with a lower educational level, Swiss citizens and unmarried people. Because of the low mortality rate in general, these differences in delays did not affect clinical outcomes. Still, tertiary prevention measures should particularly focus on these vulnerable populations.
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This research provides a description of the process followed in order to assemble a "Social Accounting Matrix" for Spain corresponding to the year 2000 (SAMSP00). As argued in the paper, this process attempts to reconcile ESA95 conventions with requirements of applied general equilibrium modelling. Particularly, problems related to the level of aggregation of net taxation data, and to the valuation system used for expressing the monetary value of input-output transactions have deserved special attention. Since the adoption of ESA95 conventions, input-output transactions have been preferably valued at basic prices, which impose additional difficulties on modellers interested in computing applied general equilibrium models. This paper addresses these difficulties by developing a procedure that allows SAM-builders to change the valuation system of input-output transactions conveniently. In addition, this procedure produces new data related to net taxation information.
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This is a six page document of Qusetions and Answer for Early Hearing Detecting and Inventation.