The influence of holes in the mechanical properties of EWT solar cells

EWT back contact solar cells are manufactured from very thin silicon wafers. These wafers are drilled by means of a laser process creating a matrix of tiny holes with a density of approximately 125 holes per square centimeter. Their influence in the stiffness and mechanical strength has been studied. To this end, both wafers with and without holes have been tested with the ring on ring test. Numerical simulations of the tests have been carried out through the Finite Element Method taking into account the non-linearities present in the tests. It's shown that one may use coarse meshes without holes to simulate the test and after that sub models are used for the estimation of the stress concentration around the holes

Homophobic Verbal and Bullying Victimization: Overlap and Emotional Impact

A relationship between homophobic verbal and bullying victimization has been established in the scientific literature, yet its findings remain debated. Similarly, the emotional impact of these phenomena may cross over, although not enough evidence is available to confirm this hypothesis. The study sought to examine this overlap of phenomena as well as their emotional impact, both independently and jointly, in a community-based school sample of adolescents with varying sexual orientations

Small-sized reverberation chamber for the measurement of sound absorption

[ES] Cámara reverberante de tamaño reducido para medidas de la absorción sonora. En este trabajo se muestra el diseño, construcción, calibración y automatización de una cámara reverberante para pequeñas muestras. Se ha buscado un equilibro entre la reducción de tamaño de las muestras para disminuir los costes de fabricación de materiales, y el volumen adecuado que permita obtener valores fiables a determinadas frecuencias. La cámara reverberante construida tiene 1.12 m3 de volumen y permite la medida de muestras de 0.3 m2. La colocación de difusores para aumentar el grado de difusión, y la automatización de las medidas, disminuyen los errores de ensayo. Se muestran también diferentes campañas comparativas de medidas en la cámara reverberante para pequeñas muestras y en la cámara normalizada. Puede verse un buen grado de ajuste entre ambas dentro del rango de frecuencias válido. Por tanto, se muestra un pequeño laboratorio que permite comparar muestras y tomar decisiones, antes de realizar la fabricación de grandes tamaños.[EN] This paper presents the design, construction, calibration and automation of a reverberation chamber for small samples. A balance has been sought between reducing sample size, to reduce the manufacturing costs of materials, and finding the appropriate volume of the chamber, to obtain reliable values at high and mid frequencies. The small-sized reverberation chamber, that was built, has a volume of 1.12 m3 and allows for the testing of samples of 0.3 m2. By using diffusers, to improve the diffusion degree, and automating measurements, we were able to improve the reliability of the results, thus reducing test errors. Several comparison studies of the measurements of the small-sized reverberation chamber and the standardised reverberation chamber are shown, and a good degree of adjustment can be seen between them, within the range of valid frequencies. This paper presents a small laboratory for comparing samples and making decisions before the manufacturing of larger sizes.This project involved the contribution of the European Union’s financial instrument, LIFE: ‘LIFE 09 ENV/ES/461: Demonstrative solutions to reduce noise pollution in industrial, using finishing technologies in textile materials’ and that of the European project ‘WOOL4BUILD ECO/13/630249/SI2.681252, CIP-ECO-INNOVATION: Improved isolation material for eco-building based on natural wool’.Rey Tormos, RMD.; Alba Fernández, J.; Bertó Carbó, L.; Gregori, A. (2017). Small-sized reverberation chamber for the measurement of sound absorption. Materiales de Construcción. 67(328):1-9. doi:10.3989/mc.2017.07316S1967328Del Rey, R., Alba, J., Ramis, J., & Sanchís, V. J. (2011). Nuevos materiales absorbentes acústicos obtenidos a partir de restos de botellas de plástico. Materiales de Construcción, 61(304), 547-558. doi:10.3989/mc.2011.59610Maderuelo-Sanz, R., Nadal-Gisbert, A. V., Crespo-Amorós, J. E., & Parres-García, F. (2012). A novel sound absorber with recycled fibers coming from end of life tires (ELTs). Applied Acoustics, 73(4), 402-408. doi:10.1016/j.apacoust.2011.12.001Rey, R. del, Alba, J., Arenas, J. P., & Sanchis, V. J. (2012). An empirical modelling of porous sound absorbing materials made of recycled foam. Applied Acoustics, 73(6-7), 604-609. doi:10.1016/j.apacoust.2011.12.009Fatima, S., & Mohanty, A. R. (2011). Acoustical and fire-retardant properties of jute composite materials. Applied Acoustics, 72(2-3), 108-114. doi:10.1016/j.apacoust.2010.10.005Ramis, J., Alba, J., Del Rey, R., Escuder, E., & Sanchís, V. J. (2010). Nuevos materiales absorbentes acústicos basados en fibra de kenaf. Materiales de Construcción, 60(299), 133-143. doi:10.3989/mc.2010.50809Ramis, J., Del Rey, R., Alba, J., Godinho, L., & Carbajo, J. (2014). A model for acoustic absorbent materials derived from coconut fiber. Materiales de Construcción, 64(313), e008. doi:10.3989/mc.2014.00513Díaz, C., Jiménez, M., Navacerrada, M. A., & Pedrero, A. (2010). Propiedades acústicas de los paneles de carrizo. Materiales de Construcción, 62(305), 55-66. doi:10.3989/mc.2010.60510Arenas, J. P., Rebolledo, J., Del Rey, R., & Alba, J. (2014). Sound Absorption Properties of Unbleached Cellulose Loose-Fill Insulation Material. BioResources, 9(4). doi:10.15376/biores.9.4.6227-624011. Bulent, E.; Aykut, K.; Haluk, K. (2012). Improving Sound Absorption Property of Polyurethane Foams by Adding Tea-Leaf Fibers. Arch. Acoust. 37 [4] 515-520.16. Hernández, D.; Liu, E.J.; Huang, J.H.; Liu, Y.C. (2015). Design and Construction of a Small Reverberation Chamber Applied to Absorption and Scattering Acoustic Measurements. Advanced Materials Research. 1077. 197–202.Bradley, D. T., Müller-Trapet, M., Adelgren, J., & Vorländer, M. (2014). Effect of boundary diffusers in a reverberation chamber: Standardized diffuse field quantifiers. The Journal of the Acoustical Society of America, 135(4), 1898-1906. doi:10.1121/1.486629123. Skålevik, M. (2011). Schroeder Frequency revisited. International Congress Forum Acustikum – Aalborg, Denmark – 2011

The Ljapunov-Schmidt reduction for some critical problems

This is a survey about the application of the Ljapunov-Schmidt reduction for some critical problems

Pseudoaneurisma de la arteria geniculada inferior medial tras reparación del ligamento del cruzado anterior.

Presentamos el caso de un varón de 24 años intervenido por una rotura crónica del ligamento cruzado anterior de rodilla izquierda. Se realizó una ligamentoplastia con técnica de cuatro fascículos con tendones ísquiotibiales. En el postoperatorio inmediato presentó un cuadro de hematoma en la zona de extracción de la plastia. Inicialmente se atribuyó a un sangrado muscular que se redujo con medidas médicas, el cuadro se repitió a los pocos días por lo que se decidió suspender el tratamiento con heparina de bajo peso molecular. Tras la mejoría se repite el hematoma, por lo que se realiza un angioTAC que muestra la presencia de un pseudoaneurisma de la arteria geniculada inferior medial. Ante la evolución tórpida del cuadro se decide la cirugía y se procede a ligar la arteria mencionada vaciándose el hematoma residual. El cuadro se resuelve sin incidencias, de modo que el paciente empieza su rehabilitación de modo habitual. Dada la infrecuencia de esta patología se revisa la bibliografía y su patogenia.We report the case of a 24 year old male with a chronic rupture of the anterior cruciate ligament in his left knee. We performed an anterior cruciate ligament reconstruction with four fascicles using the hamstrings tendon. In the immediate postoperative period, he presented a hematoma in the area of extraction plasty. Initially it was attributed to muscle bleeding and physical therapy (rest, ice and bandage) was prescribed. It reappeared few days later so it was decided to discontinue treatment with LMWH. Despite initial improvement, the haematoma reappeared so an angioCT Scan was performed showing medial inferior genicular artery pseudoaneurysm. The patient underwent a surgery for surgical wound exploration and ligation of the affected vessel. The patient improved and started the rehabilitation program as usual. Given the rarity of this disease and its pathogenesis literature is reviewed

Ensayo de capilaridad en areniscas monitorizado mediante tomografía computerizada de rayos X. Estudio comparativo con métodos convencionales

Computerized axial tomography studies were conducted to analyze water movements inside rocks (specifically in La Marina sandstone, used to build some of the historic monuments in Asturias, northern Spain). The X-ray images of water uptake by the stone interior recorded during capillarity tests provided supplementary information not furnished by conventional methods. The three-dimensional images obtained showed the position of the water front over time and its relationship to rock petrography. The volume of water-soaked rock proved to be a more realistic measure of stone capillarity. The results obtained were compared to mean capillarity measured as recommended in Spanish and European standard UNE-EN 1925:1999.La Tomografía Axial Computerizada de rayos X (TAC) ha sido aplicada al estudio del movimiento del agua en el interior de las rocas, usando como modelo la arenisca de La Marina, roca utilizada en la construcción de algunos monumentos históricos en Asturias (norte de España). Durante los ensayos de capilaridad se han registrado las imágenes de rayos X de la penetración del agua en el interior de la roca que suministran información no aportada por los métodos habituales. La reconstrucción tridimensional muestra la posición del frente de agua a lo largo del tiempo y su relación con las características petrográficas de la roca. La cuantificación del porcentaje en volumen de roca embebida en agua es una medida más real de la capilaridad de la misma. Los resultados así obtenidos han sido comparados con los de la capilaridad medida por el método descrito en la norma UNE-EN 1925:1999

Spectral-analysis-surface-waves-method in ground characterization

The prediction of train induced vibration levels in structures close to railway tracks before track construction starts is important in order to avoid having to implement costly mitigation measures afterwards. The used models require an accurate characterization of the propagation medium i.e. the soil layers. To this end the spectral analysis of surface waves (SASW) method has been chosen among the active surface waves techniques available. As dynamic source a modal sledge hammer has been used. The generated vibrations have been measured at known offsets by means of several accelerometers. There are many parameters involved in estimating the experimental dispersion curve and, later on, thickness and propagation velocities of the different layers. Tests have been carried out at the Segovia railway station. Its main building covers some of the railway tracks and vibration problems in the building should be avoided. In the paper these tests as well as the influence of several parameters on the estimated soil profile will be detailed

Asistencia farmacéutica a la prescripción para aproximar la práctica clínica a la evidencia científica

ObjetivoEl objetivo del presente estudio es valorar la utilidad de un programa de asistencia farmacéutica a la prescripción (AFP) en cuanto a la detección de problemas relacionados con los medicamentos.DiseñoRealizamos un estudio descriptivo de los hallazgos de este programa al cabo de 6 meses de rodaje.EmplazamientoEl trabajo fue realizado en 5 centros del Distrito Bahía-Cádiz de Atención Primaria.PacientesSe estudian todos los pacientes (499) incluidos a petición y criterio de su médico, que solicita asesoramiento sobre su farmacoterapia.IntervenciónImplantamos el programa de AFP en pacientes crónicos con dos finalidades básicas:1. Asistencial: detectar problemas relacionados con medicamentos y proponer soluciones individualizadas.2. Docente: aproximar los conocimientos en farmacoterapia aplicados en la práctica clínica a la evidencia científica disponible.Mediciones y resultadosNos centramos en la detección de aquellos problemas relacionados con medicamentos más frecuentes, con incidencia directa y relevante sobre la morbimortalidad. Detectamos 236 casos (47%) de posible mejora terapéutica con implicaciones importantes sobre morbilidad asociada, de los cuales 114 (23%) tenían también implicaciones sobre mortalidad. Un 56% de los pacientes recibía más de 4 medicamentos, polimedicación que podía reducirse fácilmente en un 43,5% de ellos, evitando la utilización de medicamentos de valor intrínseco no elevado.ConclusionesLa utilidad del programa resulta muy elevada al detectar numerosos problemas de gran relevancia clínica y aportar información que puede ser útil al médico para aproximar la farmacoterapia a la evidencia científica disponible.ObjectiveThe objective of this study is to assess the usefulness of a programme of attention to pharmaceutical prescriptions (APP) so as to detect medicine-related problems.DesignA descriptive study of the findings after six months operation of this programme.SettingFive primary care centres in the Bahía-Cádiz Area.PatientsAll the patients (499) who requested advice on their drug therapy and were included at the request and on the criterion of their doctor were studied.InterventionWe introduced the APP programme for chronic patients, with two basic aims:1. Care: to detect medicine-related problems and propose individual solutions.2. Teaching: to bring drug-therapy skills used in clinical practice into line with the scientific evidence available.Measurements and resultsWe focused on the detection of problems related to the most common medicines, with direct and relevant incidence on morbidity and mortality. We detected 236 cases (47%) of possible therapeutic improvement that had important implications for associated morbidity, of which 114 (23%) also had implications for mortality. 56% of the patients took more than 4 medicines, multiple medication that could easily be reduced in 43.5% of cases, so avoiding the use of medicines of low intrinsic value.ConclusionsThe programme was very useful, as numerous very clinically relevant problems were detected and information was gained that the doctor can use to bring drug therapy into line with the available scientific evidence

Distribución y patrones de diversidad de los Afódidos en la Comunidad de Madrid (Coleoptera, Scarabaeoidea, Aphodiidae, Aphodiinae y Psammodiinae)

In this work we present an updated checklist of the Aphodiidae (Coleoptera, Scarabaeoidea) from Comunidad de Madrid (Spain). In addition, the observed and potential distributions of the 70 species found in Madrid are mapped. The potential spatial distributions of species richness, rarity and endemism in this region are also mapped. Finally, we discuss briefly the origin of the observed patterns.En este trabajo se presenta un inventario actualizado de los Aphodiidae (Coleoptera, Scarabaeoidea) de la Comunidad de Madrid. Además, se presentan mapas de la distribución observada y potencial de las 70 especies encontradas en Madrid, así como de la distribución espacial de la riqueza, rareza, y endemicidad potencial en la región. Finalmente, se discute brevemente el origen de los patrones observados

Non-linear Higgs portal to Dark Matter

The Higgs portal to scalar Dark Matter is considered in the context of non-linearly realised electroweak symmetry breaking. We determine the dominant interactions of gauge bosons and the physical Higgs particle h to a scalar singlet Dark Matter candidate. Phenomenological consequences are also studied in detail, including the possibility of distinguishing this scenario from the standard Higgs portal in which the electroweak symmetry breaking is linearly realised. Two features of significant impact are: i) the connection between the electroweak scale v and the Higgs particle departs from the (v + h) functional dependence, as the Higgs field is not necessarily an exact electroweak doublet; ii) the presence of specific couplings that arise at different order in the non-linear and in the linear expansions. These facts deeply affect the Dark Matter relic abundance, as well as the expected signals in direct and indirect searches and collider phenomenology, where Dark Matter production rates are enhanced with respect to the standard portal