978 resultados para Habitat preference index
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BACKGROUND: Many emergency department (ED) providers do not follow guideline recommendations for the use of the pneumonia severity index (PSI) to determine the initial site of treatment for patients with community-acquired pneumonia (CAP). We identified the reasons why ED providers hospitalize low-risk patients or manage higher-risk patients as outpatients. METHODS: As a part of a trial to implement a PSI-based guideline for the initial site of treatment of patients with CAP, we analyzed data for patients managed at 12 EDs allocated to a high-intensity guideline implementation strategy study arm. The guideline recommended outpatient care for low-risk patients (nonhypoxemic patients with a PSI risk classification of I, II, or III) and hospitalization for higher-risk patients (hypoxemic patients or patients with a PSI risk classification of IV or V). We asked providers who made guideline-discordant decisions on site of treatment to detail the reasons for nonadherence to guideline recommendations. RESULTS: There were 1,306 patients with CAP (689 low-risk patients and 617 higher-risk patients). Among these patients, physicians admitted 258 (37.4%) of 689 low-risk patients and treated 20 (3.2%) of 617 higher-risk patients as outpatients. The most commonly reported reasons for admitting low-risk patients were the presence of a comorbid illness (178 [71.5%] of 249 patients); a laboratory value, vital sign, or symptom that precluded ED discharge (73 patients [29.3%]); or a recommendation from a primary care or a consulting physician (48 patients [19.3%]). Higher-risk patients were most often treated as outpatients because of a recommendation by a primary care or consulting physician (6 [40.0%] of 15 patients). CONCLUSION: ED providers hospitalize many low-risk patients with CAP, most frequently for a comorbid illness. Although higher-risk patients are infrequently treated as outpatients, this decision is often based on the request of an involved physician.
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We use factor augmented vector autoregressive models with time-varying coefficients to construct a financial conditions index. The time-variation in the parameters allows for the weights attached to each financial variable in the index to evolve over time. Furthermore, we develop methods for dynamic model averaging or selection which allow the financial variables entering into the FCI to change over time. We discuss why such extensions of the existing literature are important and show them to be so in an empirical application involving a wide range of financial variables.
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This paper develop and estimates a model of demand estimation for environmental public goods which allows for consumers to learn about their preferences through consumption experiences. We develop a theoretical model of Bayesian updating, perform comparative statics over the model, and show how the theoretical model can be consistently incorporated into a reduced form econometric model. We then estimate the model using data collected for two environmental goods. We find that the predictions of the theoretical exercise that additional experience makes consumers more certain over their preferences in both mean and variance are supported in each case.
Local adaptation and matching habitat choice in female barn owls with respect to melanic coloration.
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Local adaptation is a major mechanism underlying the maintenance of phenotypic variation in spatially heterogeneous environments. In the barn owl (Tyto alba), dark and pale reddish-pheomelanic individuals are adapted to conditions prevailing in northern and southern Europe, respectively. Using a long-term dataset from Central Europe, we report results consistent with the hypothesis that the different pheomelanic phenotypes are adapted to specific local conditions in females, but not in males. Compared to whitish females, reddish females bred in sites surrounded by more arable fields and less forests. Colour-dependent habitat choice was apparently beneficial. First, whitish females produced more fledglings when breeding in wooded areas, whereas reddish females when breeding in sites with more arable fields. Second, cross-fostering experiments showed that female nestlings grew wings more rapidly when both their foster and biological mothers were of similar colour. The latter result suggests that mothers should particularly produce daughters in environments that best match their own coloration. Accordingly, whiter females produced fewer daughters in territories with more arable fields. In conclusion, females displaying alternative melanic phenotypes bred in habitats providing them with the highest fitness benefits. Although small in magnitude, matching habitat selection and local adaptation may help maintain variation in pheomelanin coloration in the barn owl.
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Habitat suitability models, which relate species occurrences to environmental variables, are assumed to predict suitable conditions for a given species. If these models are reliable, they should relate to change in plant growth and function. In this paper, we ask the question whether habitat suitability models are able to predict variation in plant functional traits, often assumed to be a good surrogate for a species' overall health and vigour. Using a thorough sampling design, we show a tight link between variation in plant functional traits and habitat suitability for some species, but not for others. Our contrasting results pave the way towards a better understanding of how species cope with varying habitat conditions and demonstrate that habitat suitability models can provide meaningful descriptions of the functional niche in some cases, but not in others.
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La llúdriga (Lutra lutra) va desaparèixer de la conca de la Tordera a causa de la pressió humana sobre ella i el seu hàbitat. Recentment les seves poblacions s’estan recuperant a las conques nord de Catalunya. En aquest context es presenta els resultats dels anàlisis dels requeriments socioecològics de la llúdriga en l’afluent del riu Tordera de la riera d’Arbúcies: qualitat del bosc de ribera, valoració de la contaminació de l’aigua i l’anàlisi de les poblacions d’ictiofauna, a més de l’estimació de l’espècie més abundant. L’evolució de l’ús i cobertes del sòl del sòl mostren que existeix una tendència augment en las masses forestals, zones urbanitzades i infraestructures; també una disminució del camps de cultiu, fruiters i vinyes. La qualitat del bosc de ribera es va valorar a partir del l’índex QBR, obtenint que la màxima qualitat es localitza en el tram alt, disminuint a mesura que s’apropa a la desembocadura al Tordera. La contaminació de l’aigua a estat valorada, per una banda analitzant la qualitat biològica a partir dels índexs IPS i BMWPC, obtenint que la qualitat de l’aigua disminueix a mesura que transcorre riu avall, segons l’IPS. Amb el BMWPC es troba que existeix una recuperació de la qualitat de l’aigua en l’últim tram. Per altra banda s’han analitzat el compostos químics que afecten a la llúdriga, obtenint que les concentracions d’aquest no són rellevants a l’aigua. S’ha analitzat l’estructura de la població d’ictiofauna present, trobant que el Barbus meridionalis és l’espècie més abundant en tots el trams, a més d’augmentar en captures a mesura que l’aigua s’apropa al aiguabarreig amb la Tordera. S’ha estimat la biomassa present d’aquesta espècie, concloent que es suficient per mantenir una població no gaire densa de llúdrigues, inferior a 0,15 individus per kilòmetre de riu.
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Practice guidelines recommend outpatient care for selected patients with non-massive pulmonary embolism (PE), but fail to specify how these low-risk patients should be identified. Using data from U.S. patients, we previously derived the Pulmonary Embolism Severity Index (PESI), a prediction rule that risk stratifies patients with PE. We sought to validate the PESI in a European patient cohort. We prospectively validated the PESI in patients with PE diagnosed at six emergency departments in three European countries. We used baseline data for the rule's 11 prognostic variables to stratify patients into five risk classes (I-V) of increasing probability of mortality. The outcome was overall mortality at 90 days after presentation. To assess the accuracy of the PESI to predict mortality, we estimated the sensitivity, specificity, and predictive values for low- (risk classes I/II) versus higher-risk patients (risk classes III-V), and the discriminatory power using the area under the receiver operating characteristic (ROC) curve. Among 357 patients with PE, overall mortality was 5.9%, ranging from 0% in class I to 17.9% in class V. The 186 (52%) low-risk patients had an overall mortality of 1.1% (95% confidence interval [CI]: 0.1-3.8%) compared to 11.1% (95% CI: 6.8-16.8%) in the 171 (48%) higher-risk patients. The PESI had a high sensitivity (91%, 95% CI: 71-97%) and a negative predictive value (99%, 95% CI: 96-100%) for predicting mortality. The area under the ROC curve was 0.78 (95% CI: 0.70-0.86). The PESI reliably identifies patients with PE who are at low risk of death and who are potential candidates for outpatient care. The PESI may help physicians make more rational decisions about hospitalization for patients with PE.
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The latex of Euphorbia splendens var. hislopii, at concentrations between 5 to 12 mg/l, kills 100% of the population of Biomphalaria glabrata in a lentic habitat, after 24 h. The lyophilized latex, stocked for 18 months, killed only 34.2% of the snails, at the concentration of 5 mg/l, and 96.0% at 12 mg/l. No lethal effect was observed among Pomacea haustrum exposed to the same concentrations of the molluscicide.
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ABSTRACTA significant share of deliveries are performed by Cesarian section (C-section) in Europe and in many developed and developing countries. The aims of this thesis are to highlight the non medical, especially economic and financial, incentives that explain the use of C-section, as well as the medical consequences of C-section on women's health, in regard with other factors of ob¬stetrical care quality such as hospital concentration. Those diagnoses enable us to exhibit ways of improvement of obstetrical care quality in France. Our analysis focus on two countries, France and Switzerland. In the first part of the thesis, we show the influence of two non medical factors on the C-section use, namely the hospital payment system on the one hand and the obstetricians behaviour, especially their demand for leisure, on the other hand. With French data on the year 2003, we show firstly that the fee-for-service payment system of private for profit hospitals induces a higher probability of using C-section. Obstetricians play also a preeminent role in the decision to use a C-section, as the probability of a C-section rises with the number of obstetricians. We then focus on a French reform introduced in 2004, to investigate the impact of Prospective Payment System on obstetric practise. We show that the rise of C-section rate between 2003 and 2006 is mainly caused by changes in hospitals and patients features. Obstetricians practises do not vary a lot for patients with the same risk code. In the mean time however, the number of women coded with a high risk rises. This can be caused by improvements in the quality of coding, obstetricians chosing codes that match better the real health state of their patients. Yet, it can also show that obstetricians change their coding practises to justify the use of certain practises, such as C-section, with no regard to the health state of patients. Financial factors are not the only non medical fac¬tors that can influence the resort to C-section. Using Shelton Brown ΠΙ identification strategy, we focus on the potential impact of obstetricians leisure preference on the use of C-section. We use the distributions of days and hours of delivering and the types of C-section - planned or emergency C-sections - to show that the obstetricians demand for leisure has a significant impact on the resort to C-section, but only in emergency situations. The second part of the thesis deals with some ways to improve obstetric care quality. We use on the one hand swiss and french data to study the impact of C-section on the patients' probability of having an obstetric complication and on the other hand the influence of hospital concentration on the quality of obstetric care. We find the same results as former medical studies about the risks entailed by C-section on obstetric complications.These results prove women ought to be better informed of the medical consequences of C-section and that the slowing of C-section use should be a priority of public health policy. We finally focus on another way to improve obstetric care quality, that is hospital lmarket concentration. We investigate the impact of hospital concentration by integrating the Herfindahl-Hirschman index in our model, on health care quality, measured by the HCUP indicator. We find that hospital concentration has a negative impact on obstetric care quality, which undermines today's policy of hospital closings in France.JEL classification: 112; 118Keywords: Hospital; C-section; Payment System; Counterfactual Estimation; Quality of Care.RÉSUMÉUne part importante des accouchements sont réalisés par césarienne en Europe et dans de nom¬breux pays développés ou en développement. Les objectifs de cette thèse sont de mettre en évidence les déterminants non médicaux, notamment économiques et financiers, expliquant le développe¬ment de cette pratique, ainsi que ses conséquences sur la santé des femmes après Γ accouchement, en lien avec d'autres facteurs comme la concentration locale des structures hospitalières. Les résul¬tats exposés dans cette thèse éclairent les perspectives et voies d'amélioration de la qualité des soins en obstétriques.Notre analyse se concentre sur deux pays : la France et la Suisse. Dans la première partie de la thèse, nous mettons en évidence l'influence de deux déterminants non médicaux sur l'emploi de la césarienne : le système de paiement des hôpitaux d'une part, et le comportement des médecins obstétriciens d'autre part. En étudiant des données françaises de 2003, nous montrons d'abord que le financement à l'acte des établissements privés engendre une hausse de la proba¬bilité de pratiquer une césarienne. Le rôle de l'obstrétricien paraît également déterminant dans la décision d'opérer une césarienne, la probabilité d'employer cette technique augmentant avec le nombre d'obstétriciens. Nous nous intéressons ensuite à l'impact de la mise en place en 2004 du système de paiement prospectif sur l'évolution des pratiques obstétricales entre 2003 et 2006 en France. La hausse du taux de recours à la césarienne entre 2004 et 2006 peut ainsi être principa¬lement imputée aux évolutions des caractéristiques des hôpitaux et des patients, les pratiques des obstétriciens, pour un même codage de la situation du patient, variant peu. Dans le même temps cependant, les pratiques de codage des patients parles obstétriciens évoluent fortement, les femmes étant de plus en plus nombreuses à porter des codes correspondant à des situations à risques. Cette évolution peut indiquer que la qualité du codage en 2006 s'est améliorée par rapport à 2004, le codage correspondant de plus en plus à la situation réelle des patientes. H peut aussi indiquer que les pratiques de codage évoluent pour justifier un recours accru à la césarienne, sans lien avec l'état réel des patientes. Les facteurs financiers ne sont pas les seuls facteurs non médicaux à pouvoir expliquer le recours à la césarienne : nous nous intéressons, en suivant la stratégie d'identifica¬tion de Shelton Brown m, à l'impact potentiel de la demande de loisir des médecins obstétriciens sur la pratique de la césarienne. En utilisant la distribution des jours et heures d'accouchement, et en distinguant les césariennes planifiées de celles effectuées en urgence, nous constatons que la demande de loisir des obstétriciens influence significativement le recours à la césarienne, mais uni¬quement pour les interventions d'urgence. La deuxième partie de la thèse est consacrée à l'étude de la qualité des soins en obstétriques. Nous utilisons des données suisses et françaises pour analyser d'une part l'impact de la césarienne sur la survenue de complications obstétricales et d'autre part l'impact de la concentration des soins sur la qualité des soins en obstétrique. Nons confirmons les résultats antérieurs de la littérature médicale sur la dangerosité de la césarienne comme facteur de complications obstétricales. Ces conclusions montrent que les femmes ont besoin d'être informées des conséquences de la césarienne sur leur santé et que le ralentissement de l'augmentation de la pratique de la césarienne devrait être un objectif de la politique publique de santé. Nous nous in¬téressons à un autre facteur d'amélioration des soins en obstrétique, l'organisation des hôpitaux et particulièrement leur concentration. Nous estimons ainsi l'effet de la concentration sur la qualité des soins obstétriques en intégrant l'indice de Herfindahl-Hirschman dans notre modèle, la qualité des soins étant mesurée à l'aide de l'indicateur HCUP. Nous constatons que la concentration des naissances a un impact négatif sur la qualité des soins en obstétrique, résultat qui va dans le sens contraire des politiques de fermeture d'hôpitaux menées actuellement en France. JEL classification : 112 ; 118Mots-clés : Hôpital ; Césarienne ; Système de paiement ; Contrefactuels ; Qualité des soins, sur la qualité des soins en obstétrique.
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The latex of Euphorbia splendens var. hispolii in 12 ppm concentration (12 mg/l) caused 100% mortality for a Biomphalaria tenagophila population in a lotic habitat after 9 hr of dripfeed application. For sentinel snails, in cages placed at the water surface and buried under 0.10 m, the mortality rates varied with the distance from the application point and were: 100% (0 m); 92.6% (50 m) and 94.7% (100). No lethal effects were observed for the other living species in this habitat (Pomacea haustrum and Poecilia reticulata).
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Obesity is a major risk factor for elevated blood pressure in children. For instance, in a school-based study of 5207 children aged 10-12 years, the prevalence of hypertension, which is sustained elevated blood pressure over several visits, was 1.5%, 3.9% and 17.5% in normal weight, overweight and obese children, respectively. High body mass index (BMI) is commonly used to define overweight and obesity. However, because BMI is merely a proxy for adiposity, there is a longstanding debate about its performance to predict elevated blood pressure (or any other health conditions associated with adiposity) and whether other adiposity indicators, such as waist circumference, waist-to-hip ratio or hip circumference, should not be preferred... In this study, 7.4% of boys and 6.4% of girls had elevated blood pressure. The adiposity indicators were highly correlated to each other, apart from weight, waist-to-hip ratio and skinfold thickness z-scores. All indicators were associated with blood pressure. The ability to identify children with elevated blood pressure, assessed by the area under the receiver operating curve (AUC) statistic, was superior for BMI, body adiposity index and waist-to-height ratio z-scores compared with other indicators. BMI z-scores had a slightly higher AUC than other indicators. The authors concluded that BMIz-scores could be a better predictor of elevated blood pressure in children than other adiposity indicators.
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The present work was carried out in a watercress garden in Alto da Boa Vista, in the city of Rio de Janeiro, Brazil. The investigation was carried out in two phases. The first one (1985-86) involved the sampling of Biomphalaria tenegophila in two areas to determine its relative populational densities. The results showed that the populations presented similar densities and dynamics. The second phase (1988-89) involved the study of the influence of some environmental factors on the establishment of B. tenagophila in watercress garden. Two factors were identified as responsible for the establishment of B. tenagophila in the garden: (1) the quality of the water entering the irrigation system, to which domestic sewage is added, and (2) alterations in the nature of the substrate, due to inadequate fertilization techniques, which employ organic matter from adjacent pigsties. Aquatic plants and hydrological parameters of the irrigation system were subsidiary factors to the establishment of B. tenagophila in the garden.