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16 páginas, 10 figuras, 3 tablas., The variability of winter precipitation in the west of the Iberian Peninsula is strongly affected by the North Atlantic Oscillation (NAO). This study focuses on identifying the relationship that exists between precipitation registered in the city of Leon (in northwestern Spain), the NAO index and the associated weather type during the same period. In order to achieve this objective, the prevailing weather type has been calculated for each day in Leon from January 1948 to March 2009, using the objective Lamb Weather Types classification method. The most significant results appear in winter (from December to March). During these months an increase has been observed in the frequency of anticyclonic weather type (A) (very dry), and a decrease in the cyclonic (C), south-westerly (SW) and westerly (W) types (the three rainiest weather types). The positive trend in the NAO index could be the main cause of the decrease in the frequency of the three rainiest weather types (C, SW and W) and therefore, responsible for the relevant decline in winter precipitation observed in the city of Leon. The high correlation coefficients between the NAO index, the frequency of the three rainiest weather types and winter precipitation suggests an interesting method to forecast rainfall. Using a binary logistic regression model, a downscaling model for daily precipitation has been obtained based on the weather types and the NAO index. The daily results obtained for the winter months are good (TSS = 0.64) bearing in mind that only sea level pressure data were used in the logistic model., This study was partially supported by the Regional Government of Castile and Le´on (Grants LE014A07 and LE039A10-2), and by the Spanish Ministry of Education (Grants TEC2007-63216 and TEC2010-19241-C02-01).

This paper studies the influence of the North Atlantic Oscillation (NAO) on monthly, seasonal and annual precipitation regimes in continental Spain. The data used for this study include the monthly rain series of 325 meteorological stations distributed homogeneously over the study zone, and the monthly NAO indices from 1961 to 1998. A total of 5525 rain series were employed for the analysis. Simple and multiple linear correlations were established between these variables in different combinations. The main aim was to check whether monthly, seasonal or annual precipitation data could be predicted using earlier precipitation data and the NAO index. The geographical areas where the stations have shown a statistically significant correlation have been represented on maps. The results differ depending on the correlation, but, in general, the best results have been found in the fall and winter months. Finally, a practical application of the method was carried out in the Ebro Valley and it was observed that the combination of the NAO index for spring and summer and the precipitation registered in those two seasons may be useful to forecast rain in the fall. Este trabajo estudia la influencia de la Oscilación del Atlántico Norte (NAO) en el régimen de precipitaciones mensuales, estacionales y anuales de la España Peninsular. Para ello se han utilizado los datos mensuales de precipitación de 325 estaciones pluviométricas repartidas homogéneamente y los índices mensuales del índice NAO desde 1961 a 1998; se han usado un total de 5525 series de precipitación. El estudio se ha realizado mediante correlaciones lineales simples o múltiples entre estas variables utilizando diferentes combinaciones. Se trata de ver si se podría predecir la precipitación mensual, estacional o bien anual a partir de datos previos de precipitación y del índice NAO. Se han representado espacialmente las zonas geográficas cuyos observatorios manifiestan una correlación estadísticamente significativa. Los resultados difieren del tipo de correlación elegido, pero en general los mejores resultados se encuentran en los meses de invierno. Por último, se ha aplicado esta metodología al Valle del Ebro y se ha observado que una combinación del índice NAO de primavera y verano, junto con la precipitación registrada en esas dos estaciones podría ser útil para predecir la precipitación de otoño. published

The value of project-based learning has lead to the inclusion of project development activities in engineering courses, being the Final Year Project (FYP) the most remarkable one. Several approaches have been proposed for assessing and grading FYPs but, among them, rubrics are becoming a standard for such type of assessment. However, due to the different characteristics and orientations of the projects (some are more practically oriented, some more theoretically), and the high amount of different competences to be evaluated (knowledge, working capability, communication skills, etc.), the definition of one unique rubric suitable for the evaluation of all FYPs presented in different degree programs, is a big challenge. In a former work, the educational outcomes expected from the FYP were defined and resulted in a proposal for their assessment. Afterwards, the proposal has been tested during one year within an educational innovation-project at the Universidad Politécnica de Madrid which involved the follow-up of 8 undergraduate telecommunication students elaborating their FYPs. In this publication, our experience will be described, based on the emerging work taking place through the formalisation of the process which consisted in the following steps: i) establishment of a schedule for the whole process (publication of FYPs topics, selection of applying students and their enrolment, assignation of a jury to each FYP, elaboration and follow-up of FYPs, final report submission, oral presentation, etc.); ii) design of rubrics for each of three assessment parts: working process, final report and oral presentation; and iii) follow-up and evaluation of the involved FYPs. Finally, problems that appeared during this experience (e.g. administrative aspects, criticisms and suggestions from the students, tutors and juries involved) are discussed and some modifications in the assessment system will be proposed in order to solve or minimize these problems.

12 páginas, 5 figuras., Annual, seasonal and monthly rainfall trends from 1961 to 2006 period were analysed in this study by applying various statistical tools to data from 553 Spanish weather stations. The magnitude of the trends was derived from the slopes of the regression lines using the least squares method, while the statistical significance was determined using the non-parametric Mann-Kendall test. Geostatistical interpolation techniques were applied to generate rainfall trend surfaces. Combining classic trends tests and spatially interpolated precipitation permits the spatio-temporal visualization of detected trends. Updated trends reveal that rainfall is generally decreasing in January, February, March, April, and June. Around 61, 44 and 12% of the whole territory is evidencing significant negative trends in February, June and March, respectively. Significant precipitation decreases are also noted in more than 28% of Spain in summer and winter. On the contrary, rainfall is significantly increasing in October in more than 21% of Spain and areas mainly located in north-western areas. May, August, September and autumn also show significant positive trends in the period 1961-2006, although the percentages are lower than for negative trends. Finally, the annual precipitation is significantly decreasing in 11% of the territory. © 2010 Royal Meteorological Society., Authors would like to acknowledge AEMET (Spanish Meteorological Agency) for providing precipitation data.

During the last years, the lecturers at the Circuits and Systems Engineering Department at the E.U.I.T. de Telecomunicación at the Universidad Politécnica de Madrid are observing more and more serious mathematical errors in the different exams and exercises taken by the students. Although some of these mistakes can be considered unacceptable in engineering disciplines, it is possible for a student to pass the final exam regardless of these mistakes. In this scenario, and aware that results were getting worse and worse year after year, it was considered convenient, and almost indispensable, to develop math exercises that students must practice if they want to progress following a continuous and formative assessment method along their engineering studies. The first part of this work is to analyze basic mathematical errors in final exam exercises of the course “Signals and Systems”. We present and illustrate the most relevant errors detected during the last two years final exams of that course. The information obtained permits us to identify the main lacks, difficulties and defaults of the students. The second part of this work is to develop a training module in order to the students can practice as many times as they want with simple exercises dealing with the topics where frequent errors are detected. After practicing they must pass an initial test to make sure that students have acquired the adequate basic mathematical background and skills to progress successfully in the mentioned course. The questions and exercises have been written using different formats, most of them to be compatible with Moodle platform requirements.

Introduction: This study was designed to compare the plasma lipid peroxidation (LPO) levels in preterm and full-term neonates and their respective mothers, to assess their relationship with the degree of oxidative stress and the levels of vitamin C, an important antioxidant of the body. Material and methods: The studied groups included 70 neonates, 30 preterm (24-36 weeks of gestation) and 40 full-term (37-42 weeks) neonates. Blood samples were obtained from the cord blood in neonates and from the antecubital vein in their mothers at the time of delivery. Plasma susceptibility to LPO was fluorometrically measured before and after its incubation with 2,2'-azobis-2- amidinopropane hydrochloride (AAPH). Plasma vitamin C level was measured by HPLC. Results: The basal LPO levels were similar in all groups of patients. After AAPH incubation, however, plasma LPO significantly (P, This work was partially supported by grants G03/137, PI02/1447 and PI03/0817 from Instituto de Salud Carlos III, Spain, and CTS-101 from Consejería de Educación, Junta de Andalucía, Spain.

2-13 july 2007

september 2007