978 resultados para 357-M0070B
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O objetivo deste trabalho foi avaliar os índices de vegetação e bandas do vermelho e do infravermelho próximo, gerados a partir dos sensores HRVIR, ETM+ e Modis, nas estimativas de índice de área foliar e produtividade da cultura do feijoeiro. O experimento foi realizado em blocos ao acaso, com parcelas subdivididas, com quatro lâminas de irrigação (179,5, 256,5, 357,5 e 406,2 mm), três doses de N (0,0, 80,0 e 160,0 kg ha-1) e quatro repetições. As medidas de reflectância foram obtidas com o Spetron SE-590, no estádio R6 da cultura, nas 48 parcelas. Foram testados: a razão simples, o índice de vegetação por diferença normalizada, índice de vegetação ajustado ao solo e índice de vegetação realçado. Os índices de vegetação foram eficientes na estimativa do índice de área foliar (IAF) e da produtividade da cultura do feijoeiro. Os índices de vegetação e a banda do infravermelho apresentam o mesmo potencial na estimativa do IAF, quando se considera a resolução espectral dos sensores Modis, ETM+ e HRVIR.
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The usefulness of species distribution models (SDMs) in predicting impacts of climate change on biodiversity is difficult to assess because changes in species ranges may take decades or centuries to occur. One alternative way to evaluate the predictive ability of SDMs across time is to compare their predictions with data on past species distributions. We use data on plant distributions, fossil pollen and current and mid-Holocene climate to test the ability of SDMs to predict past climate-change impacts. We find that species showing little change in the estimated position of their realized niche, with resulting good model performance, tend to be dominant competitors for light. Different mechanisms appear to be responsible for among-species differences in model performance. Confidence in predictions of the impacts of climate change could be improved by selecting species with characteristics that suggest little change is expected in the relationships between species occurrence and climate patterns.
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Epithelioid neoplasms are generally carcinomas. As confirmation that every rule is meant to be broken, some sarcomas demonstrate epithelioid morphology, and can even express cytokeratins. These sarcomas have unique behavior, for example, a much higher rate of lymph node metastasis than other sarcomas. This group of sarcomas also presents diagnostic and therapeutic challenges to those clinicians who help patients contend with these difficult tumors. In this review, some of the major categories of epithelioid soft tissue tumors are described, with clinical data reported as available. Some of these tumors provide excellent opportunities to examine newer protein-targeted agents in investigational settings.
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Les anomalies vasculaires constituent des affections rares présentes dès la naissance. Elles sont classées selon leur histologie en tumeurs ou malformations vasculaires. La connaissance de ces anomalies par le médecin de famille est importante, permettant ainsi leur diagnostic, qui repose essentiellement sur la clinique. Les caractéristiques anatomiques et hémodynamiques de l'anomalie sont précisées par l'angiologue grâce à l'écho-Doppler. Cet examen permet un suivi de la lésion et le diagnostic d'éventuelles complications. Un bilan radiologique peut compléter cette évaluation avant discussion multidisciplinaire en vue d'un traitement parfois difficile. Dans cet article, un bref aperçu des malformations vasculaires et de leur prise en charge multidisciplinaire est discuté, en particulier dans le cas du syndrome de Klippel-Trenaunay. Vascular anomalies are rare conditions that could be observed at all ages. They are classified, according to their histology, in vascular tumors or vascular malformations. The general practitioner plays a significant role in diagnosis and patient management, diagnosis being suspected on clinical history. In case of vascular anomaly, ultrasound-Doppler assessment is helpful to characterize morphologic and hemodynamic changes of the lesion and permits to monitor the evolution and to detect complications. Further investigations are often necessary prior to multidisciplinary management. In this article, a brief overview of vascular anomalies, their multidisciplinary management and the exemple of Klippel-Trenaunay syndrome are presented.
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Collection : Archives de la linguistique française ; 357
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This work deals with the cooling of high-speed electric machines, such as motors and generators, through an air gap. It consists of numerical and experimental modelling of gas flow and heat transfer in an annular channel. Velocity and temperature profiles are modelled in the air gap of a high-speed testmachine. Local and mean heat transfer coefficients and total friction coefficients are attained for a smooth rotor-stator combination at a large velocity range. The aim is to solve the heat transfer numerically and experimentally. The FINFLO software, developed at Helsinki University of Technology, has been used in the flow solution, and the commercial IGG and Field view programs for the grid generation and post processing. The annular channel is discretized as a sector mesh. Calculation is performed with constant mass flow rate on six rotational speeds. The effect of turbulence is calculated using three turbulence models. The friction coefficient and velocity factor are attained via total friction power. The first part of experimental section consists of finding the proper sensors and calibrating them in a straight pipe. After preliminary tests, a RdF-sensor is glued on the walls of stator and rotor surfaces. Telemetry is needed to be able to measure the heat transfer coefficients at the rotor. The mean heat transfer coefficients are measured in a test machine on four cooling air mass flow rates at a wide Couette Reynolds number range. The calculated values concerning the friction and heat transfer coefficients are compared with measured and semi-empirical data. Heat is transferred from the hotter stator and rotor surfaces to the coolerair flow in the air gap, not from the rotor to the stator via the air gap, althought the stator temperature is lower than the rotor temperature. The calculatedfriction coefficients fits well with the semi-empirical equations and precedingmeasurements. On constant mass flow rate the rotor heat transfer coefficient attains a saturation point at a higher rotational speed, while the heat transfer coefficient of the stator grows uniformly. The magnitudes of the heat transfer coefficients are almost constant with different turbulence models. The calibrationof sensors in a straight pipe is only an advisory step in the selection process. Telemetry is tested in the pipe conditions and compared to the same measurements with a plain sensor. The magnitudes of the measured data and the data from the semi-empirical equation are higher for the heat transfer coefficients than thenumerical data considered on the velocity range. Friction and heat transfer coefficients are presented in a large velocity range in the report. The goals are reached acceptably using numerical and experimental research. The next challenge is to achieve results for grooved stator-rotor combinations. The work contains also results for an air gap with a grooved stator with 36 slots. The velocity field by the numerical method does not match in every respect the estimated flow mode. The absence of secondary Taylor vortices is evident when using time averagednumerical simulation.
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Internet supone un fuerte giro en la manera tradicional de operar y de relacionarse de las empresas. Está claro que estamos inmersos en un proceso que evoluciona muy rápidamente y que es una realidad tanto en el mundo, en general, como en nuestro país, en particular. Las estadísticas sobre el sector nos muestran fríamente una realidad que es necesario explicar, tanto en sus causas como en sus consecuencias.
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En aquest estudi es pretén analitzar la composició social i ideològica dels quatre consistoris municipals que es van formar a la ciutat de Lleida al Trienni Liberal. A l'inici d'aquesta nova etapa històrica ja es va comprovar com els individus (sobretot nobles) que van controlar l'Ajuntament de Lleida al sexenni absolutista posterior a la Guerra del Francés van perdurar, per tant, no es produir cap revolució. Tot i que poc a poc aquests elements més absolutistes i com a màxim més identificats amb el liberalisme més moderat i proper al tradicionalisme van anant deixant pas a una nova classe dirigent política procedent dels sectors socials més dinàmics (professions liberals i activitats comercials), la qual va fer-se amb el consistori lleidatà a l'any 1823, va ser el triomf dels "exaltats". Aquesta experiència va finalitzar amb la invasió dels Cent Mil Fills de Sant Lluís i la posterior destrucció del règim constitucional.
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España se ha convertido en los últimos años en el mayor receptor de inmigrantes de la Unión Europea. Consecuentemente, sus hijos e hijas se han incorporado a nuestras escuelas planteando unos retos hasta hace poco desconocidos. Uno de ellos, y tal vez el que más preocupa al profesorado, se refiere al desarrollo de niveles de competencia lingüística suficientes para poder seguir una escolaridad vehiculada a través de una lengua que en muchas ocasiones tiene poco en común con la suya propia (L1). En este contexto, a partir de una muestra de 49 niños y niñas inmigrantes que fueron comparados con un grupo de 44 escolares autóctonos de su misma edad y nivel escolar, nuestro trabajo analiza el progreso en el conocimiento de la lengua castellana y la incidencia que en ello tienen factores como el tiempo de estancia en el país de acogida y la lengua familiar. Los resultados obtenidos apuntan a un proceso lento y complejo del que no queda excluido incluso aquel alumnado cuya lengua L1 coincide con variantes hispanoamericanas del castellano.
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El objetivo de nuestro artículo es analizar la presentación del Islam, de los musulmanes y de las culturas árabe y musulmana en los libros de texto. Nos basamos en un enfoque metodológico complementario, entre cuantitativo y cualitativo. En el estudio cuantitativo, se han analizado 246 documentos (el 84,1% de los cuales son manuales y libros de texto; el 10,2%, libros de ejercicios; el 4,2%, documentos de acompañamiento y el 1,1%, guías del profesor) que incluyen la totalidad de las asignaturas de la enseñanza no universitaria de Cataluña. Una primera aproximación a los resultados nos permite observar el predominio de referencias en la asignatura de Historia de Bachillerato con diferencias estadísticamente significativas respecto a los porcentajes que se dan en otras disciplinas. Otras asignaturas de ciencias sociales como el Conocimiento del Medio en Primaria (11,7%) o las Ciencias Sociales en ESO (8%) también muestran una buena proporción de representaciones. En el resto de materias, las referencias presentan porcentajes que oscilan entre el 1% y el 5%. Por otra parte, en el 46,2% de los textos analizados no se ha encontrado ni una sola referencia. En el estudio cualitativo (análisis del discurso), que hemos desarrollado a partir de la revisión de un centenar de libros de texto de ciencias sociales correspondientes a los niveles educativos de ESO y Bachillerato, se han seleccionado diez extractos (seis de contenido verbal y cuatro de representaciones icónicas). En esta segunda revisión, se comprueba que solo algo menos de los dos tercios de los textos (64%) contiene alguna alusión –ya sea verbal o icónica– a las culturas musulmanas o al resto de los temas anteriormente citados. Los datos que hemos obtenido ponen de manifiesto la necesidad de revisar y actualizar los contenidos de nuestros libros escolares con respecto a las omisiones y deformaciones del tratamiento del Islam, las culturas musulmanas y la presencia de musulmanes en nuestra sociedad.
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En este artículo se expone una síntesis del estado del conocimiento sobre los efectos que tienen los embalses en el tramo fluvial aguas abajo de los mismos, en lo referente al régimen hidrológico, el transporte de sedimentos y la morfología del cauce.
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This multicenter, observational prospective cohort study addresses the risk associated with exposure to mirtazapine during pregnancy. Pregnancy outcomes after exposure to mirtazapine were compared with 2 matched control groups: (1) exposure to any selective serotonin reuptake inhibitor (SSRI, control subjects with a psychiatric condition) and (2) no exposure to medication known to be teratogenic or any antidepressant (general control subjects). Data were collected by members of the European Network of Teratology Information Services between 1995 and 2011. Observations from 357 exposed pregnancies were compared with 357 pregnancies from each control group. The rate of major birth defects between the mirtazapine and the SSRI group did not differ significantly (4.5% vs 4.2%; odds ratio [OR], 1.1; 95% confidence interval [95% CI], 0.5-2.3; P = 0.9). A trend toward a higher rate of birth defects in the mirtazapine group compared with general control subjects (4.5% vs 1.9%; OR, 2.4; 95% CI, 0.9-6.3; P = 0.08) reached statistical significance after exclusion of chromosomal or genetic anomalies (4.1% vs 1.3%; OR, 3.3; 95% CI, 1.04-10.3; P = 0.03), but this difference became again nonsignificant if cases of exposure not comprising the first trimester were excluded from the analysis (3.4% vs 1.9%; OR, 1.8; 95% CI, 0.6-5.0; P = 0.26). The crude miscarriage rate did not differ significantly between the mirtazapine, the SSRI, and the general control groups (12.1% vs 12.0% vs 9.3%; P = 0.44). However, a higher rate of elective pregnancy termination was observed in the mirtazapine group compared with SSRI and general control subjects (7.8% vs 3.4% vs 5.6%; P = 0.03). This study did not observe a statistically significant difference in the rate of major birth defects after first-trimester exposure between mirtazapine, SSRI-exposed, and nonexposed pregnancies. A marginally higher rate of birth defects was, however, observed in the mirtazapine and SSRI groups compared with the low rate of birth defects in our general control subjects. Overall pregnancy outcome after mirtazapine exposure was similar to that of the SSRI-exposed control group.
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PURPOSE OF REVIEW: Only 5% of the Alzheimer's cases are explained by genetic mutations, whereas the remaining 95% are sporadic. The pathophysiological mechanisms underlying sporadic Alzheimer's disease are not well understood, suggesting a complex multifactorial cause. This review summarizes the recent findings on research aiming to show how biomarkers can be used for revealing the underlying mechanisms of preclinical stage Alzheimer's disease and help in their diagnosis. RECENT FINDINGS: The undisputed successful publicly accessible repositories provide longitudinal brain images, clinical, genetic and proteomic information of Alzheimer's disease. By combining with increasingly sophisticated data analysis methods, it is a great opportunity for searching new biomarkers. Innovative studies validated theoretical models of disease progression demonstrating the sequential ordering of well-established biomarkers. Novel observations shed light on the interaction between biomarkers to confirm that disease progression is related to multiple pathological factors. A typical example is the tau-associated neuronal toxicity that can be additionally potentiated by amyloid β peptides. To increase further the complexity, studies report specific impact of common genetic variants that can be traced from childhood through middle age up to the symptomatic onset of Alzheimer's disease. SUMMARY: The discovery of efficient therapies to prevent the disease or modify the progression of disease requires a more thorough understanding of the underlying biological processes. Neuroimaging, genetic and proteomic biomarkers for Alzheimer's disease are critically discussed and proposed to be included in clinical descriptions and diagnostic guidelines.
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BACKGROUND: In Switzerland, the incidence of hepatitis C virus (HCV) infection in HIV-positive men who have sex with men (MSM) rose 18-fold between 1998 and 2011. We aimed to evaluate transmission risk factors, awareness, and seroprevalence of HCV among MSM in southwest Switzerland. METHODS: From 1st June 2011 to 31st August 2012, trained health care professionals invited individuals attending (1) MSM screening clinics and (2) indoor and outdoor meeting areas to complete an anonymous questionnaire. Consenting participants were rapid tested for HCV (OraQuick HCV Rapid Antibody Test). RESULTS: Of 918 MSM approached, 654 agreed to participate, most of whom (536, 82%) were enrolled via MSM screening clinics. Of 654 participants, 21 (3.2%) disclosed being HIV positive; 140 (21%) had unknown HIV status. In the preceding 12 months, 357 (55%) of 654 participants reported unprotected anal intercourse (UAI) and 321 (49%) of 654 participants reported UAI with partners of different/unknown HIV status. Not HIV serosorting was reported more frequently among HIV-positive individuals (76%, P < 0.001). Three hundred two participants (46%) were aware of HCV, awareness being higher among clinic than meeting area participants (49% vs. 33%, P = 0.04). One individual (of 654; 0.2%), with a negative HIV test result 18 months previously was newly diagnosed as being HCV positive on rapid testing. CONCLUSIONS: In this sample of predominantly HIV-negative MSM, half the participants were aware of HCV and HCV seroprevalence was low. However, high rates of UAI and of UAI without HIV serosorting were reported. Given the increasing incidence of HCV among HIV-positive men, we propose that HCV counseling should be offered to MSM regardless of HIV status, with testing offered to those at high risk.