153 resultados para Encinas


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Objective: Alterations in the size of the [CAG](n) repeats of the AR gene have been described in several types tumors. The purpose of this study was to evaluate if there is an association between the AR [CAG](n) repeat alleles and the relative risk for head and neck cancer and to analyse microsatellite instability (MSI) and loss of heterozygosity (LOH) in these tumors.Design: Matched samples of blood and head and neck tumors were evaluated using two methodologies, silver-stained gels to perform the analyses of MSI and LOH, and automated analysis to confirm these results and for genotyping of the AR [CAG](n), repeat length. Sixty-nine individuals without cancer were used as a control group for both procedures. The Log-rank test was used to compare overall survival and disease-free survival curves. The Cox proportional hazards regression models were performed to determine the [CAG], repeats as an independent prognostic factor.Results: Patients with alleles <= 20 in the male group showed a correlation with lower disease-free survival (P = 0.0325) and with recurrence or metastasis (RR 2.52, CI 95%). in the female group, the allele 2 (longer allele) showed a significant lower mean of [CAG](n), repeat when compared to the control group. Microsatellite instability was detected in nine cases in both procedures. In six out of these nine cases, we observed a reduction of the AR [CAG](n) repeat length. LOH was detected in one out of 17 women informative for oral cancer in both procedures.Conclusion: These results suggest that short [CAG](n) repeat length (: 20) polymorphism is associated with poor prognosis in a subset of male patients with head and neck cancer and that AR gene microsatellite instability is uncommon in these tumors. (C) 2007 Elsevier Ltd. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Background: Uterine leiomyomas are common, benign, smooth muscle tumors representing a significant public health problem. The aim of this study was to investigate CYP17A1, CYP19, and androgen (AR) polymorphisms, their relative risks for uterine leiomyomas and possible associations with clinical parameters.Methods: Uterine leiomyoma tissues and blood samples were obtained from 87 patients, as were peripheral blood samples from 68 control women. Clinical data were recorded in both groups. The CYP17A1 (rs743572) polymorphism was analyzed by PCR-RFLP, and the CYP19 [TTTA](n) repeat and AR [CAG](n) repeat were analyzed using PCR-based GeneScan analysis. AR loss of heterozygosity (LOH) and microsatellite instability were also evaluated, while samples exhibiting LOH were analyzed for X inactivation.Results: Clinical parameters related to disease development did not differ between cases and controls. CYP17A1 *A2/*A2 genotype was prevalent in non-white women. CYP17A1, CYP19, and AR genotypes and alleles did not differ between groups. However, alleles presenting [TTTA](7) repeats in intron 4 of CYP19 were more frequent in the control group (p=0.0550). Shorter and longer [CAG]n repeat alleles of AR were exclusive to the leiomyoma group. The LOH assay showed allele losses at AR locus in four informative tumors and X chromosome inactivation analysis revealed that these tumors retained the active allele.Conclusions: The overall lack of association between uterine leiomyomas with polymorphisms involved in steroidogenesis or steroid metabolism is consistent with the hypothesis that these polymorphisms do not substantially contribute to the development of these tumors.

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Background: Previous reports into the role of [CAG]n repeat lengths in the androgen receptor (AR) gene indicate that these may play an important part in the development and progression of breast cancer, however, knowledge regarding benign breast lesions is limited. Patients and Methods: PCR-based GeneScan analysis was used to investigate the [CAG]n repeat length at exon 1 of the AR gene in 59 benign breast lesions (27 fibroadenomas, 18 atypical hyperplasias, and 14 hyperplasias without atypia) and 54 ductal breast carcinomas. Seventy-two cancer-free women were used as a control group. In addition, [CAG]n repeats were evaluated for the presence of loss of heterozygosity (LOH) and microsatellite instability (MSI) in a subset of these samples (27 fibroadenomas, 14 hyperplasias without atypia and 22 breast carcinomas). Results: Shorter [CAG]n repeat lengths were strongly correlated with atypical hyperplasias (p=0.0209) and carcinomas (p<0.0001). LOH was found in 1/12 and 4/20 informative cases of hyperplasias without atypia and breast carcinomas, respectively. Three patients with breast carcinoma who had previously presented atypical hyperplasia showed a reduction in the [CAG]n repeat length in their carcinomas. Conclusion: Short [CAG]n repeat length (≤20) polymorphisms are strongly associated with breast carcinomas and atypical hyperplasias. Although non-significant, a subgroup of patients with breast carcinoma and genotype SS showed an association with parameters of worse outcome.

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Incluye Bibliografía

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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In the competitive judo, the form as a trainer organizes the process of his/her athlete's training is a very important task for a good acting and a better use of the technical procedures. There is great importance in determining the exercise intensity for the judocas training due to the interest for the high income in several competitions, and few studies returned for this research area, involving those athletes' different physiologic conditions. Therefore, it is necessary to improve protocols of physical evaluation for this modality, increasing his/her applicability. The present study aimed at to verify the validity of a protocol of specific aerobic test of the judo (technique ipon-seoi-nague), no exhausting, adapted of the method of CHASSAIN (1986), using deltas of variations of the lactacidemia and of the Scale of Perception of Effort of Borg, in athletes well. The test adapted to the judo constituted of four exercise series with two efforts similar (double) of 180 seconds with one interval of 90 seconds among them. The series of exercises were accomplished in consecutive days. The intensities of the double tests were of 85%, 95%, 105% and 115% of the minimum lactato for each participant. This work used the technique ipon-seoi-nague, obeying the reasons effort-pause individualized for each athlete, that you/they correspond to the intensities of exercises proposed by the protocol of CHASSAIN (1986). In that way, the athletes applied a blow (maximum speed) and they rested some seconds, depending on the regime effort-pause of the session. At the end of each collection collection of blood (25NL) of each participant's earlobe was accomplished, seeking to measure the concentration of sanguine lactato. The collections were accomplished at the end of the first and of the second efforts, in each one of the series. For the analysis of the Perception of the athletes' Effort, the Scale of Perception... (Complete abstract click electronic access below)

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Objective: To evaluate a new triaxial accelerometer device for prediction of energy expenditure, measured as VO2/kg, in obese adults and normal-weight controls during activities of daily life. Subjects and methods: Thirty-seven obese adults (Body Mass Index (BMI) 37±5.4) and seventeen controls (BMI 23±1.8) performed eight activities for 5 to 8 minutes while wearing a triaxial accelerometer on the right thigh. Simultaneously, VO2 and VCO2 were measured using a portable metabolic system. The relationship between accelerometer counts (AC) and VO2/kg was analysed using spline regression and linear mixed-effects models. Results: For all activities, VO2/kg was significantly lower in obese participants than in normalweight controls. A linear relationship between AC and VO2/kg existed only within accelerometer values from 0 to 300 counts/min, with an increase of 3.7 (95%-confidence interval (CI) 3.4 - 4.1) and 3.9 ml/min (95%-CI 3.4 - 4.3) per increase of 100 counts/min in obese and normal-weight adults, respectively. Linear modelling of the whole range yields wide prediction intervals for VO2/kg of ± 6.3 and ±7.3 ml/min in both groups. Conclusion: In obese and normal-weight adults, the use of AC for predicting energy expenditure, defined as VO2/kg, from a broad range of physical activities, characterized by varying intensities and types of muscle work, is limited.

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Un aspecto clave para lograr la regeneración de dehesas y montes bajos, los sistemas más extensos de aprovechamiento de la encina en España, son las características fisiológicas de la bellota. Se analizó la capacidad germinativa de bellotas procedentes de 15 encinas (familias) en dehesa y 15 familias en monte bajo de la misma finca, tras someterlas en laboratorio a heladas de distinta intensidad (-3ºC, -6ºC, -9ºC, -12ºC, -15ºC). Las bellotas procedentes de dehesa tuvieron una capacidad germinativa menor y con mayor variabilidad entre familias, aunque heladas incluso moderadas (-6ºC) afectaron en mayor medida a la germinación de las bellotas de montes bajos, si bien la reducción fue ya generalizada (60% en todas las familias); tras la exposición a -12ºC o inferior, la germinación fue residual en todos los casos. Se concluye que bajas temperaturas son un factor limitante para la regeneración de la encina en el interior de la península Ibérica.

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La dehesa es el sistema agroforestal español más conocido y estudiado; hoy en día está protegido por la Directiva Hábitats 43/92/CEE (6310-Dehesas perennifolias de Quercus ssp.) e incluida en la red Natura 2000. El objetivo de este trabajo es analizar la contribución del arbolado a la producción y diversidad de los pastos herbáceos en la dehesa del centro peninsular. El trabajo se ha desarrollado en la finca “El Dehesón del Encinar” (Término Municipal de Oropesa, provincia de Toledo), en una parcela de 5 ha representativa de la dehesa tipo en la zona. Se muestrearon marcos de 50 x 50 cm de lado considerando dos posiciones bajo copa según la proximidad del tronco (1/2 radio y en el borde) en cuatro orientaciones: Norte, Sur, Este y Oeste, en 12 encinas en distintas localizaciones dentro de la parcela. Para cada marco de muestreo se estudió la composición florística completa de los pastos herbáceos y la contribución de cada especie a la producción en materia seca. Se utilizó un modelo GLM para ver la relación entre la riqueza específica y otras variables (producción, calidad de estación y situación bajo copa). La diversidad beta fue medida mediante el índice de Whittaker, comparando las comunidades herbáceas en las distintas situaciones presentes. En la zona de estudio encontramos que la calidad de los pastos herbáceos está íntimamente relacionada con la riqueza específica a través de la abundancia de leguminosas. Los valores superiores de riqueza se encontraron en los bordes de las copas del arbolado así como en encinas situadas en las zonas más ricas en leguminosas de la parcela general. Con respecto a la diversidad beta, no existen diferencias notables entre las comunidades de pastos herbáceos bajo las distintas encinas estudiadas; las localizaciones de la parcela con mayor riqueza específica y producción de leguminosas también muestran mayores diferencias (índices de Whittaker superiores) en la comparación de comunidades a distintas distancias del fuste (>50% de especies distintas). Constatamos y cuantificamos la importancia del estrato arbóreo en la producción y diversidad de los pastos herbáceos de la dehesa

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En la práctica habitual, para la elaboración de morteros se recomienda la utilización de granulometrías continuas. El requisito de continuidad y que los tamaños de partícula se encuentren dentro de los límites establecidos por “husos granulométricos” surge de las teorías clásicas de Fuller – Thompson y se apoya en la necesidad de obtener mezclas con adecuada docilidad en el estado fresco. Sin embargo, las distribuciones continuas de árido no representan las únicas alternativas para obtener mezclas que tengan una adecuada docilidad en estado fresco y mediante nuevos criterios de interferencia de partículas es posible demostrar que las distribuciones discontinuas aun siendo más compactas y con menor requerimientos de volumen de pasta pueden ser igual de dóciles en estado fresco. Aunque el volumen mínimo de pasta está condicionado por su fluidez y viscosidad estos parámetros pueden modificarse mediante la incorporación de filler de distinta naturaleza y aditivos químicos de reciente desarrollo. En consecuencia, se propone analizar la posibilidad de minimizar el contenido de pasta de morteros de base cemento, manteniendo las prestaciones en el estado fresco, con el objetivo de obtener una mejor estabilidad volumétrica, posibilitando mejor control de la retracción y de la fisuración. Para ello se emplearán criterios de interferencia de partículas, combinados con el uso de filler de distinta naturaleza La reducción del contenido de pasta conducirá también a mejorar el perfil sostenible de los morteros. El proceso de optimización tiene una base racional y, por lo tanto, será aplicable a distintos tipos de mortero, y las proporciones óptimas podrán adecuarse según las prestaciones requeridas para el material. SUMMARY In common practice, continuous sand gradings are recommended to produce ordinary mortars. This requirement, along with grading limits are based on classical theories, such as Fuller, aimed at achieving a reasonable packing density without compromising workability at the fresh state. Nevertheless, there are other alternatives, such as discontinuous curves based on particle interference criteria, which are capable of having even higher packing density. The less the content of voids in the granular skeleton, the less the amount of cement paste required to fill in these voids and coating the particles. Yet, the minimum volume of paste in a mortar is determined by requirements associated to the fresh state and thus, fluidity and viscosity of the paste play a significant role on the matter. These two properties can be modified by the use of suitable fillers and by the use of last-generation chemical admixtures. As a result, it is proposed to analyse the possibility of combining current particle interference criteria with the use of different types of filler and chemical admixtures to optimise cement-based mortar formulations. This optimisation is aimed at reducing the paste content while maintaining a suitable performance at the fresh state. The reduction in paste content would lead to a better dimensional stability, with better control of shrinkage and cracking behaviour. The foreseen optimisation process will have a strong rational basis and thus, it should be potentially useful to optimise mortar proportions according to a performance-based approach.

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En este trabajo se comparan dos estrategias de evaluación a través de cuestionarios online: i) realizar un cuestionario de evaluación sumativa al final de cada bloque temático del curso o ii) permitir que, para cada bloque temático, el alumno pueda repetir varias veces un test (con realimentación de las respuestas correctas) y realizar un test similar después de esta fase de aprendizaje. Los resultados muestran varios beneficios de la segunda estrategia: una mayor participación de los alumnos hasta el final del semestre, una menor tasa de abandono de la asignatura y una mejor nota en los test. Sin embargo, para que el aprendizaje sea efectivo en el caso de repetir varias veces un test, se necesita un banco de preguntas suficientemente amplio para que exista una probabilidad baja de que las preguntas no se repitan. Este problema se ha resuelto utilizando la posibilidad que presentan algunas plataformas de gestión del aprendizaje de generar automáticamente variantes numéricas de una misma pregunta. Por último se observa un grado de acuerdo muy elevado por parte de los alumnos con el peso que los resultados de los tests tienen en la nota final del curso, en el caso bajo estudio. Abstract: This work compares two different assessment strategies through online tests: i) summative assessment tests at the end of each part of the course or ii) the students can do selfassessment tests (with feedback) prior to a summative assessment test at the end of each part of the course. Results show that the second strategy yields several benefits: an increment in student participation till the end of the semester, a reduction in the drop-out rate and an increase in the mean test marks. However, a large item bank is necessary to effectively implement this second strategy. This problem has been addressed by using the automatic item generation facility offered by several learning management systems. Finally, a high proportion of the students agree with the weight proposed for these tests in the final course mark.

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This paper studies the effect of different penetration rates of plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EV) in the Spanish electrical system. A stochastic model for the average trip evaluation and for the arriving and departure times is used to determine the availability of the vehicles for charging. A novel advanced charging algorithm is proposed, which avoids any communication among all agents. Its performance is determined through different charging scenarios.

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Doñana, a National Park since 1969, a UNESCO site since 1994 among other protected area designations of national and international character, is a coastal dune and marshland ecosystem of outstanding importance for biodiversity and conservation at the mouth of the Guadalaquivir River, Southwest Spain. However, the Doñana natural area is seriously threatened by global change factors such as humanly induced climate change, habitat loss, overexploitation of ecosystem services, and pollution. Not all stakeholders are convinced of the benefits of the national park, and management of Doñana, its environs and watershed are the subject of intense disagreement. This interplay between natural characteristics of great value with intense human pressure makes Doñana a fascinating workshop for the study of global human environment interactions. Here, we discuss the role of stakeholders in the application of a cellular automatabased model to Doñana and its environs and present the results of a series of exercises undertaken with stakeholders to parametrize the model, something often done by researchers without stakeholder engagement. By engaging with stakeholders early in the project, feedback generated from workshops contributes to model development. Stakeholders are therefore contributors of empirical data for the model as well as independent evaluators providing local and specialist knowledge.