Las herramientas de autor en el proceso de producción de cursos en formato digital

El auge de la educación con el empleo de las Tecnologías de la Información y las Comunicaciones (TIC) ha hecho del proceso de producción de cursos en formato digital, un elemento de suma importancia para un adecuado desarrollo del proceso de enseñanza aprendizaje en estas condiciones. Este artículo contiene algunas reflexiones sobre la importancia de las herramientas de autor en el proceso de producción de cursos y cómo pueden mejorarse sus características para elevar la independencia del profesor en el proceso.The educational improvement with the use of the new technologies of the information and communications (TIC) has led the production process on digital format course, an element of great importance for an adequate development of the teaching - learning process in these conditions. This article contains some reflections about the authoring tools in the production process of the course, and how can its characteristics get better in order to raise independence of the professor during the process

A new Method for determining Compound Specific Carbon Isotope of Chlorinated Solvents in Porewater

A new method for the extraction of chlorinated solvents (CSs) from porewater with dimethylacetamide (DMA) used as a solvent and the determination of δ13C by gas chromatography-isotope ratio mass spectrometry (GC-IRMS) with solid-phase microextraction (SPME) are presented. This method was used for the determination of δ13C of chloroethenes and chloromethanes. The extraction of the CSs from porewater with DMA led to a minimal loss of mass of solvent and chlorinated compounds. The accuracy of the method was verified with the analysis of the pure injected compounds using elemental analyser - isotope ratio mass spectrometry (EA-IRMS). It has been effectively applied in a study area in saturated soil samples of a pollutant source zone of perchloroethylene (PCE) and trichloroethylene (TCE). The limit of quantification of the new method was 0.034 µg/g for PCE and TCE for 10-20 g of soil sample. This new method allows for compound-specific isotope analysis (CSIA) of CSs in porewater, which can be beneficial in sites where the identification of contamination sources and the behaviour of the contaminants are not clear

Natural attenuation of pools and plumes of carbon tetrachloride and chloroform in the transition zone to bottom aquitards and the microorganisms involved in their degradation

In the transition zone between aquifers and aquitards, DNAPL pools of carbon tetrachloride and chloroform accumulate because of heterogeneity in this zone. Natural attenuation occurs at pools and plumes, indicating that remediation might be possible. The aims of the study were: i) to assess the role of heterogeneity in the natural attenuation of these compounds, ii) determine degradation processes within this zone, and iii) identify dechlorinating microorganisms. For this, groundwater concentrations, redox-sensitive parameters, CSIA isotopic and DGGE molecular techniques were used. The main findings at depth of the transition zone were: (1) the important key control played by heterogeneity on natural attenuation of contaminants. (2) Heterogeneity caused the highly anoxic environment and dominant sulfate-reducing conditions, which accounts for more efficient natural attenuation. (3) Heterogeneity also explains that the transition zone constitutes an ecotone. (4) The bacteria size exclusion is governed by the pore throat threshold and determines the penetration of dechlorinating microorganisms into the finest sediments, which is relevant, since it implies the need to verify whether microorganisms proposed for bioremediation can penetrate these materials. (5) Reductive dechlorination caused the natural attenuation of contaminants in groundwater and porewater of fine sediments. In the case of carbon tetrachloride, it was an abiotic process biogenically mediated by A. suillum, a bacterium capable of penetrating the finest sediments. In the case of chloroform, it was a biotic process performed by a Clostridiales bacterium, which is unable to penetrate the finest materials. (6) Both microorganisms have potential to be biostimulated to dechlorinate contaminants in the source and the plume in the transition zone. These outcomes are particularly relevant given the longevity of DNAPL sources and have considerable environmental implications as many supply wells in industrial areas exploit aquifers contaminated by chlorinated solvents emerging from DNAPL pools accumulated on the low-conductivity layers in transition zones

Thermal characterisation of compact heat exchangers for air heating and cooling in electric vehicles

[EN] The use of air conditioning in all-electric cars reduces their driving range by 33% in average. With the purpose of reducing the energy consumption of the vehicle and optimising the performance of the batteries, the mobile air-conditioning can be integrated with the temperature control system of the powertrain by means of a coolant loop. In such layouts, the air-to-coolant heat exchangers must operate efficiently in both air heating and cooling modes. Dynamic simulation tools comprising the entire thermal system are essential to assess its performance. In this context, fast but accurate models of the system components are required. This paper presents the thermal characterisation of a commercial compact louvered-fin flat-tube heat exchanger (heater core) for this novel application, based on an experimental campaign comprising 279 working points that reflect real air-conditioning (heating and cooling) working conditions. A general methodology to fit a single correlation of the global heat transfer coefficient for both dry and wet working conditions is explained. The semiempirical correlation developed is employed in a single-node model of the heat exchanger that requires minimal computation time. The present model predicts the heat transfer rate with an average deviation of 3.5% in the cases with dehumidification and 1.9% in the cases when the heat exchanger remains dry.This work has been supported by the European Commission under the 7th European Community framework program as part of the ICE project ‘‘MagnetoCaloric Refrigeration for Efficient Electric Air-Conditioning”, Grant Agreement no. 265434. B. Torregrosa-Jaime acknowledges the Spanish Education, Culture and Sport Ministry (Ministerio de Educación, Cultura y Deporte) for receiving the Research Fellowship FPU ref. AP2010-2160.Torregrosa-Jaime, B.; Corberán, JM.; Payá-Herrero, J.; Delamarche, JL. (2017). Thermal characterisation of compact heat exchangers for air heating and cooling in electric vehicles. Applied Thermal Engineering. 115:774-781. https://doi.org/10.1016/j.applthermaleng.2017.01.017S77478111

Resultados de un programa de ahorro de sangre en prótesis de rodilla unilateral

La implantación de una prótesis de rodilla es un procedimiento que frecuentemente requiere reposición hemática en el postoperatorio inmediato. Entre las alternativas a la sangre alogénica, se ha propuesto la autodonación como una opción segura y efectiva; sin embargo, este procedimiento no está exento de controversia dada la anemia preoperatorio que supone para el paciente y el elevado coste de las unidades no utilizadas y, por tanto, desechadas. Se presentan los resultados obtenidos a lo largo de los últimos tres años con el uso no restrictivo de un programa de autotransfusión en pacientes en quienes se implantó una prótesis de rodilla unilateral. Las cifras obtenidas muestran una ligera reducción en la tasa de transfusión alogénica, pero con una eficiencia baja. Se plantean otras alternativas de reposición hemática y el perfil de pacientes que sería candidatos a seguir en un programa de autodonación.Total knee replacement is a procedure that frequently need postoperative blood transfusion. Instead of allogeneic blood, predeposit autologous transfusion has been proposed as a safe and efficient choice; nevertheless, this procedure is not free of debate due to the anaemia caused to the patients and the high number of no-used, and lost, units. We report the results of a no restrictive program of blood autologous transfusion in patients having a knee replace- ment, in the period between 2001 to 2003. The numbers show a slight decrease in the rate of allogeneic blood transfusion; nonetheless, with a short efectivenuess. We analyse other alternatives for blood transfusion and in what patients this procedure should be done

Semen parameters can be predicted from environmental factors and lifestyle using artificial intelligence methods

Fertility rates have dramatically decreased in the last two decades, especially in men. It has been described that environmental factors as well as life habits may affect semen quality. In this paper we use artificial intelligence techniques in order to predict semen characteristics resulting from environmental factors, life habits, and health status, with these techniques constituting a possible decision support system that can help in the study of male fertility potential. A total of 123 young, healthy volunteers provided a semen sample that was analyzed according to the World Health Organization 2010 criteria. They also were asked to complete a validated questionnaire about life habits and health status. Sperm concentration and percentage of motile sperm were related to sociodemographic data, environmental factors, health status, and life habits in order to determine the predictive accuracy of a multilayer perceptron network, a type of artificial neural network. In conclusion, we have developed an artificial neural network that can predict the results of the semen analysis based on the data collected by the questionnaire. The semen parameter that is best predicted using this methodology is the sperm concentration. Although the accuracy for motility is slightly lower than that for concentration, it is possible to predict it with a significant degree of accuracy. This methodology can be a useful tool in early diagnosis of patients with seminal disorders or in the selection of candidates to become semen donors.This study was partially funded by Vicerrectorado de Investigación, University of Alicante, Alicante, Spain (Vigrob-137)

The role of ecotones in the dehalogenation of chloroethenes in alluvial fan aquifers

The presence of ecotones in transition zones between geological strata (e.g. layers of gravel and sand interbedded with layers of silt in distal alluvial fan deposits) in aquifers plays a significant role in regulating the flux of matter and energy between compartments. Ecotones are characterised by steep physicochemical and biological gradients and considerable biological diversity. However, the link between organic pollutants and degradation potential in ecotones has scarcely been studied. The aim of this study is to relate the presence of ecotones with the dehalogenation of chloroethenes. A field site was selected where chloroethene contamination occurs in a granular aquifer with geological heterogeneities. The site is monitored by multilevel and conventional wells. Groundwater samples were analysed by chemical, isotopic, and molecular techniques. The main results were as follows: (1) two ecotones were characterised in the source area, one in the upper part of the aquifer and the second in the transition zone to the bottom aquitard, where the aged pool is located; (2) the ecotone located in the transition zone to the bottom aquitard has greater microbial diversity, due to higher geological heterogeneities; (3) both ecotones show the reductive dehalogenation of perchloroethylene and trichloroethylene; and (4) these ecotones are the main zones of the reductive dehalogenation of the pollutants, given the more reductive conditions at the centre of the plume. These findings suggest that ecotones are responsible for natural attenuation, where oxic conditions prevailed at the aquifer and bioremediation strategies could be applied more effectively in these zones to promote complete reductive dehalogenation

Acoustic behavior of the VEGA launch pad environment

[EN] The acoustic pressure levels experienced by the spacecraft and launchers during the lift-off is due among other factor by the reflection of the sound waves on the launch pad. The acoustic load distribution in the area of the launcher depends on the geometric, mechanical and acoustic characteristics of the ground facilities. This work is intended to study the acoustic environment of the launch pad. A numerical and experimental investigation is developed in order to study in the linear regime the acoustic behaviour of a subscale model of the VEGA's launch pad. The acoustic measurements are performed in an anechoic chamber using an electroacoustic source that emits incoherent noise, mimicking the real acoustic source. The acoustic pressure field is measured at different positions in front of the launch pad mock-up, in the area where the acoustic waves are reflected. Among the future perspectives of this work is to study and develop new methods for the mitigation of the sound pressure levels.Authors acknowledge the support of the European Space Agency under contract ¿Sonic Crystals For Noise Reduction At The Launch Pad¿ ESA ITT 1-7094 (ITI) and the 441-2015 Co-Sponsered PhD ¿Acoustic Reduction Methods for the Launch Pad¿. The work was supported by Spanish Ministry of Economy and Innovation (MINECO) and European Union FEDER through project FIS2015-65998-C2-2. Authors aknowledge Dhéric Mutel, Cyril Bernard and Clément Jost for their contribution to this workPicó Vila, R.; Herrero-Durá, I.; Sánchez Morcillo, VJ.; Salmerón-Contreras, LJ.; García-Raffi, LM. (2016). Acoustic behavior of the VEGA launch pad environment. Universidade do Porto. 1-6. http://hdl.handle.net/10251/181097S1

Flood Hazard Management in Public Mountain Recreation Areas vs. Ungauged Fluvial Basins. Case Study of the Caldera de Taburiente National Park, Canary Islands (Spain)

Las Angustias River is an ungauged stream in the Caldera de Taburiente National Park (Spain), where frequent intense flash-flood events occur. The aim of this research is to analyze the flood hazard at the Playa de Taburiente. Based on the limited information available (short time-series of daily precipitation), a statistical frequency analysis of 24 h rainfall was completed and the precipitation results were transformed into surface runoff. To determine if the model underestimates the flows that are generated in the basin, the dendro-geomorphological information available was used to calibrate results. The results of the HMS model were significantly lower. At this point, both the rainfall data and the rainfall-runoff model were re-analyzed to maximize the rainfall intensity values and the runoff generated (increasing the CN value for the basin). For the 1997 flood event, a 1250 m3·s−1 flood minimizes the RMSE for the disturbed tree sample; this flow value also clearly exceeds any peak flow derived from the rainfall-runoff analysis. It is only when rainfall intensity and surface runoff are maximized that the peak flows obtained approximate those associated with dendro-geomorphological data. The results highlight the difficulties of flood hazard management in ungauged torrential basins in mountain recreational areas (such as National Parks). Thus, in the absence of flow records, when considering the maximum rainfall intensity scenario may be a useful and effective tool for flood risk management

Lesiones en el hombro causadas por electrocución

Las lesiones en el hombro tras sufrir una descarga eléctrica son raras. Presentamos siete pacientes con luxaciones y fracturas en el hombro debidas a una electrocución. Un alto porcentaje de estas lesiones se diagnostican tarde, empeorando de esta manera el pronóstico. Por ello, ante una electrocución, debemos pensar en una lesión de hombro.Shoulder injuries after an electrical shock are rare. We report seven cases with dislocation and fractures of the shoulder due to electrocution. A high percentage of these lesions are diagnosed late, worsening thus the prognosis. This is why, after an electrocution, a shoulder injury should be considered