Influence of the boundary conditions on the natural frequencies of a Francis turbine

Natural frequencies estimation of Francis turbines is of paramount importance in the stage of design in order to avoid vibration and resonance problems especially during transient events. Francis turbine runners are submerged in water and confined with small axial and radial gaps which considerably decrease their natural frequencies in comparison to the same structure in the air. Acoustic-structural FSI simulations have been used to evaluate the influence of these gaps. This model considers an entire prototype of a Francis turbine, including generator, shaft, runner and surrounding water. The radial gap between the runner and the static parts has been changed from the real configuration (about 0.04% the runner diameter) to 1% of the runner diameter to evaluate its influence on the machine natural frequencies. Mode-shapes and natural frequencies of the whole machine are discussed for all the boundary conditions testedPostprint (published version

La variabilidad espacio-temporal del régimen térmico en España como fundamento para evaluar los efectos potenciales del estado del tiempo sobre la salud humana

Ponencia presentada en: VIII Congreso de la Asociación Española de Climatología celebrado en Salamanca entre el 25 y el 28 de septiembre de 2012.[ES]La temperatura del aire resulta un elemento meteorológico determinante en los estudios para evaluar los efectos del estado del tiempo sobre la salud de los seres vivos, incluyendo al hombre. Las variaciones espacio-temporales de este elemento condicionan respuestas específicas del sistema termorregulador y, en consecuencia, por encima o por debajo de ciertos límites fisiológicos individuales, los cambios bruscos de la temperatura del aire pueden producir efectos meteoro-trópicos significativos entre la población más susceptible. Se utiliza un método de trabajo fundamentado en las variaciones espacio-temporales del complejo temperatura máxima-mínima diaria del aire. Este procedimiento ha sido adaptado a las condiciones españolas y se han procesado más de 100 puntos de observación con datos públicos de la AEMET estandarizados y representativos para el período 1981-2010. Se demuestra que las variaciones bruscas y anómalas del régimen térmico constituyen un significativo factor de riesgo para la salud humana.[EN]The air temperature is a decisive meteorological element in the studies to evaluate the effects of weather changes on the health of the living organisms, including man. The time and space variations of this element produce specific physiological responses of the thermal regulation system and, in consequence, above or below certain individual physiological threshold, the abrupt changes of the air temperature may produce significant meteor-tropic effects among the most sensitive population. A work method based upon the objective classification of the time and space variations of the daily extreme air temperatures was used. This procedure has been implemented to the Spanish conditions with the aim the AEMET public climate data from more than 100 climate stations. The whole information was completed and standardized for the period 1981-2010. It was demonstrated that the abrupt and anomalous variations of the thermal regime constitute a significant risk factor for the human health

Microbial community structure of vineyard soils with different pH and copper content

The phospholipid fatty acid (PLFA) pattern of vineyard soils from the Northwest of the Iberian Peninsula was studied to identify soil factors determining the microbial community structure, with special emphasis on effects of Cu pollution and pH. A wide range of soil samples, collected from six winegrowing regions (Rías Baixas, Ribeiro, Ribeira Sacra, Monterrei, Valdeorras and Vinhos Verdes) was analyzed. Physico-chemical properties, including total Cu content, five different Cu fractions and available Cu, were also determined. Total Cu varied between 33 and 1120 mg kg1 and pHwater between 4.3 and 7.3. Soil pH rather than Cu content was most important in determining the composition of the microbial community. An increase in the relative concentrations of the monounsaturated PLFAs 16:1ω5, 16:1ω7c, 17:1ω8 and 18:1ω7 and a decrease of br18:0, i17:0, 17:0 and cy19:0 was correlated to an increase in pH. A significant effect of Cu was also found, with an increase in the branched fatty acids 10Me17:0, i16:0, 10Me18:0, a17:0 and br17:0 as consequence of Cu pollution. This change in the PLFA pattern was correlated to both the total and available fractions of Cu. Although the PLFA pattern was a useful tool to assess factors affecting the microbial composition, it is difficult to differentiate between these factors.Xunta de Galicia | Ref. 09MDS013291P

In vivo authentication of Iberian pig feeding regime using faecal volatilome information

Nowadays, people are increasingly interested in the food they consume. Authenticity and natural origin are amongst the most valued issues of food products by society. Although various national and international laws have been created for the regulation of labelling and trade of food, unfortunately, they are often not effective in avoiding food product fraud. The Iberian pig and the cured products obtained with this breed have a great international reputation due to their high quality and added value. However, the authentication of these pigs feeding regime is sometimes difficult. Therefore, the objective of this study was to use faecal volatilome information to differentiate the different feeding regimes which determine the final commercial category of Iberian products. Individual faeces samples were sampled on 10 farms from 133 Iberian pigs to evaluate their volatilome through gas chromatography (GC) coupled to ion mobility spectrometry (IMS). The intensity of GC-IMS plot features were extracted and chemometric tools were employed to develop two different models: one, focused on the discrimination between acorn-fed (completely natural diet grazed) and feed-fed samples, and another one for commercial category classification. Both models were carried out in duplicate, using spectral fingerprint information and a different approach studying specific markers. Good classification rates were obtained in both models: 92,3% and 96,3% were the rates obtained in acorn-fed vs feed-fed model with fingerprint and specific markers information, respectively; and the same classification success was also achieved with both approaches in the second model, focused on commercial category classification. The misclassified samples in both models, which belonged to acorn-fed pigs, may be related to the diet heterogeneity of these animals and the differences in natural resources foraged. The results of the present study highlight GC-IMS as an useful tool to carry out an in vivo authentication of Iberian pig feeding regime and the subsequent commercial category, as well as to avoid labelling fraud. Further studies including larger number of samples are needed in order to obtain more complex models to classify very different samples

Numerical study on the influence of acoustic natural frequencies on the dynamic behaviour of submerged and confined disk-like structures

The dynamic response of disks has been deeply studied in the last years given that their dynamic characteristics present similarities with more complex disk-like structures used in real engineering applications, such as hydraulic turbine runners. Because of disk-like structures could present fatigue damage or critical failures as a result of resonance conditions, it is of paramount importance to determine their natural frequencies. The dynamic response of disk-like structures is heavily affected by the added mass effect when they are surrounded by a heavy fluid. This added mass is greatly affected by the proximity of walls. Furthermore, the surrounding fluid cavity has its own natural frequencies and mode shapes, called acoustic natural frequencies and acoustic mode-shapes. All studies of submerged and confined disks have been carried out considering that the acoustic natural frequencies of the surrounding fluid cavity are much higher than the natural frequencies of the disk, so they do not affect each other. However, in some cases the acoustic natural frequencies are close to the natural frequencies of the submerged structure, which can be affected considerably. This case has not been deeply discussed yet. In this paper, the influence of the acoustic natural frequencies of a cylindrical fluid cavity on the natural frequencies of a disk has been analysed numerically. First, the effect of the added mass of the fluid has been estimated when the acoustic natural frequencies of the fluid cavity are much higher than the natural frequencies of the disk. For this case, different geometrical and material parameters have been considered. Then, the parameters that affect the acoustical natural frequencies of the fluid cavity have been identified. Finally, the case with acoustic natural frequencies close to the structural natural frequencies is studied in detail and the affectation between both is discussed. All the results presented in this paper have been dimensionless in order to be used for a wide range of disk-like structures. Therefore, with this study it is possible to identify for which conditions the dynamic response of a generic disk-like structure will be affected by the acoustic natural frequencies of its surrounding fluid cylindrical cavity.Peer ReviewedPostprint (published version

Clasificación compleja y objetiva de los estados del tiempo diarios según la estructura del régimen térmico del aire y otros indicadores biometeorológicos

Ponencia presentada en: VIII Congreso de la Asociación Española de Climatología celebrado en Salamanca entre el 25 y el 28 de septiembre de 2012.[ES]Recientes estudios han permitido demostrar que la estructura del régimen térmico del aire, definida según el comportamiento predominante de las temperaturas máximas y mínimas diarias, constituye un primer paso para evaluar los efectos potenciales de los cambios bruscos del tiempo atmosférico como factor de riesgo para la salud humana. En el presente trabajo se propone un criterio de clasificación compleja de los estados del tiempo diarios (ETD) para su aplicación biometeorológica en el territorio español. Se pone de manifiesto la estrecha relación existente entre los cambios inter-diarios de elevado contraste en el estado del tiempo y el aumento notable en la ocurrencia diaria de algunas enfermedades crónicas no transmisibles. Los resultados obtenidos permiten diseñar un sistema de alerta sanitaria a partir de pronósticos biometeorológicos con la capacidad de prevenir la ocurrencia de condiciones biometeorológicas peligrosas para la salud humana.[EN]Recent studies have demonstrated that the time and space variations of the air thermal regime, based upon the behavior of daily extreme air temperatures, constitutes a good approach to evaluate the potential effects of abrupt weather changes on human health, and therefore, they may be considered such a significant risk factor for human health. The present work gives the fundaments for the development of a complex classification criterium of daily weather types (DWT) for its biometeorological use into the Spanish territory. A strong relationship among the occurrence of interdaily contrasting weather changes and the remarkable daily increase of some chronic non communicable diseases was found. The obtained results allowed the design of an early health alert system, based upon objective models of biometeorological forecasts. This operational system may inform to the medical institutions up to 7 days in advance on the occurrence of dangerous meteortropic effects. It will permit to mitigate their impacts on the health of the most sensitive groups of the local population

Clarithromycin Effect in Microbial Communities

Financiaciado para publicación en acceso aberto: Universidade de Vigo/CISUGA laboratory experiment was carried out to investigate the response of the microbial communities in acid agricultural soils located in the NW Iberian Peninsula to the presence of clarithromycin. Four soils, with different organic C content and similar pH, and seven different concentrations of clarithromycin (0.49, 1.95, 7.81, 31.25, 125, 500 and 2,000 mg kg−1 of soil) were used, and microbial estimates were made after 8 and 42 incubation days. The phospholipid fatty acids (PLFA) technique was used to estimate the total microbial biomass and biomass of specific microbial groups as well as the microbial community structure (PLFA pattern). The microbial biomass (total and specific groups) was different in the four studied soils, the lowest values being exhibited by soils with the lowest organic C. The antibiotic addition showed a positive effect on microbial biomass (total and specific groups), especially at the highest dose; the effect being similar or even more accentuated with time passed after the addition (42 days ≥8 days). Principal component analysis (PCA) of the PLFA data carried out with the whole data set showed that the main determining factors of the microbial structure followed the order: soil > time incubation ≥ antibiotic dose. When the PCA was performed individually for each incubation time, the results indicated that microbial communities of the four soils were different. Likewise, for each soil, different microbial communities were observed depending on antibiotic concentration. The microbial biomass and PLFA pattern data were coincidentally showing that the clarithromycin addition favored fungi and G− bacteria more that bacteria and G+ bacteria; the effect being dose-dependent. Our data (microbial biomass, PLFA pattern) also demonstrated that the effect of clarithromycin addition on microbial communities in these four acid agricultural soils persisted even after 42 incubation days.Xunta de Galicia | Ref. ED481B-2022-081Ministerio de Ciencia, Innovación y Universidades | Ref. RTI2018-099574-B-C21Ministerio de Ciencia, Innovación y Universidades | Ref. RTI2018-099574-B-C22Ministerio de Ciencia, Innovación y Universidades | Ref. FPU21/0420

Can compost improve the bio-photovoltaic energy produced by peppers? Results from the ENERGYCOMPO project

Comunicación oral presentada en: III congreso CAOS, Granada EEZ, España. 4 mayo 202

Characteristics of attack phases in boys' 14 and under basketball competition

El objetivo de este estudio fue describir las características de la competición de baloncesto de categoría infantil masculina, para analizar si se adapta a las capacidades y necesidades formativas de los jugadores. La muestra estuvo compuesta por 2252 fases de ataque. Las variables analizadas fueron número de fases de ataque, tipo de fase de ataque, duración de la fase de ataque y número de pases por fase de ataque. El estudio se realizó mediante metodología observacional. En todas las variables se encontraron diferencias significativas entre equipos. Los datos muestran que la competición podría ser susceptible de mejorar si se modificasen algunos de los valores obtenidos en las variables analizadas.fueron número de fases de ataque, tipo de fase de ataque, duración de la fase de ataque y número de pases por fase de ataque. El estudio se realizó mediante metodología observacional. En todas las variables se encontraron diferencias significativas entre equipos. Los datos muestran que la competición podría ser susceptible de mejorar si se modificasen algunos de los valores obtenidos en las variables analizadas.Este estudio ha sido financiado por el Ministerio Español de Economía y Competitividad: DEP2011-13702-E y PFE-MICINN-OS/10

The Wnt signaling receptor Fzd9 is essential for Myc-driven tumorigenesis in pancreatic islets

Zacarías-Fluck, et al identify and validate the Wnt receptor Fzd9 as a key effector of Myc-Wnt signaling cross-talk in a mouse model of Myc-driven pancreatic insulinomas. The huge cadre of genes regulated by Myc has obstructed the identification of critical effectors that are essential for Myc-driven tumorigenesis. Here, we describe how only the lack of the receptor Fzd9, previously identified as a Myc transcriptional target, impairs sustained tumor expansion and β-cell dedifferentiation in a mouse model of Myc-driven insulinoma, allows pancreatic islets to maintain their physiological structure and affects Myc-related global gene expression. Importantly, Wnt signaling inhibition in Fzd9-competent mice largely recapitulates the suppression of proliferation caused by Fzd9 deficiency upon Myc activation. Together, our results indicate that the Wnt signaling receptor Fzd9 is essential for Myc-induced tumorigenesis in pancreatic islets