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

Social educircation, un projecte internacional de circ social

El circ social és una estratègia d’intervenció psicosocial que actualment es troba en expansió, es tracta d’un potent facilitador de processos de transformació social que s’utilitza, principalment, amb poblacions que es troben en una situació vulnerable. Els col·lectius a què es dirigix són tots els que es troben en risc d’exclusió social: menors, persones amb discapacitat, integrants d’ètnies minoritàries, col·lectius d’immigrants i refugiats, entre altres. En el circ social, l’objectiu principal no és tant el perfecte assoliment de les disciplines escolars, quant el foment de les habilitats per al canvi social i el desenvolupament íntegre de la persona, nodrint la seua autoestima i la confiança en els altres, afavorint ’adquisisió d’habilitats de relació, el respecte al seu cos com a ferramenta de treball i d’expressió artística i a ser conscient del seu potencial

Resilience effects of SGK1 and TAP1 DNA markers during PRRSV outbreaks in reproductive sows

The porcine reproductive and respiratory syndrome virus (PRRSV) is a major infectious stressor that causes serious health problems and productivity drops. Based on previous genome-wide analyses, we selected SGK1 and TAP1 as candidate genes for resilience, and genotyped three mutations, including a 3′UTR variant SGK1_rs338508371 and two synonymous variants TAP1_rs1109026889 and TAP1_rs80928141 in 305 Landrace × Large White sows. All polymorphisms affected the reproductive performance in the outbreak, but not during the endemic phase, thereby indicating a potential use of these markers for resilience. Moreover, some genotypes were associated with a stable performance across PRRSV phases. Thus, in the outbreak, the SGK1_rs338508371 AA sows had less piglets born alive (p < 0.0001) and more stillborns (p < 0.05) while other sows were able to keep their productivity. During the outbreak, TAP1_rs80928141 GG sows had less piglets born alive (p < 0.05) and both TAP1 polymorphisms influenced the number of mummies in an additive manner (p < 0.05). Remarkably, TAP1_rs80928141 AA sows had around one mummy more than GG sows (p < 0.01). Resilience to PRRSV could be improved by including the SGK1 and TAP1 markers in crossbreeding and/or selection schemes, as they contribute to maintaining a stable number of piglets born alive and lost, particularly mummies, despite the outbreak.This research and the APC were partially funded by FEDER projects COMRDI16-1-0035-03 and RTI2018-097700-B-I00 from the Spanish Ministry of Science, Innovation, and Universities. M.L. received a postdoctoral grant from UdL-Impuls programme

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

A dynamic global model for planktonic foraminifera

International audienceSeasonal changes in the flux of planktonic foraminifera have to be understood to interpret corresponding proxy-based reconstructions. To study the seasonal cycle of planktonic foraminifera species we developed a numerical model of species concentration (PLAFOM). This model is forced with a global hydrographic dataset (e.g. temperature, mixed layer depth) and with biological information taken from an ecosystem model (e.g. "food type", zooplankton abundance) to predict monthly concentrations of the most common planktonic foraminifera species used for proxies: N. pachyderma (sinistral and dextral varieties), G. bulloides, G. ruber (white variety) and G. sacculifer. The sensitivity of each species with respect to temperature (optimal temperature and range of tolerance) is derived from sediment-trap studies. Overall, the spatial distribution patterns of most of the species are comparable to core-top data. N. pachyderma (sin.) is limited to polar regions, N. pachyderma (dex.) and G. bulloides are the most common species in high productivity zones like upwelling areas, while G. ruber and G. sacculifer are more abundant in tropical and subtropical oligotrophic waters. Modeled seasonal variation match well with sediment-trap records in most of the locations for N. pachyderma (sin), N. pachyderma (dex.) and G. bulloides. G. ruber and G. sacculifer show, in general, lower concentrations and less seasonal variability in all sites. The lower variability is reflected in the model output, but the small scale variations are not reproduced by the model in several locations. Due to the fact that the model is forced by climatological data, it can not capture interannual variations. The sensitivity experiments we carried out show that, inside the temperature tolerance range, food availability is the main parameter which controls the abundance of some species. The here presented model represents a powerful tool to explore the response of planktonic foraminifera to different boundary conditions, and to quantify the seasonal bias in foraminifera-based proxy records

Simple metal-free oxidative cleavage of 1,2-diols

Cleavage of 1,2-diols is easily carried out under mild conditions with the Oxone/KBr (or Oxone/NaCl) method in either acetonitrile/water or tert-butanol/water medium at room temperature. This procedure is highly efficient for the cleavage of dihydroxyfatty esters and acids. The reaction takes place through a double oxidation of the 1,2-diol, leading to the 1,2-diketone that undergoes a Baeyer-Villiger oxidation, with a final hydrolysis of the generated anhydride. The application to other diols, including simple internal and terminal diols, is also possible, but the nature of the diol substrate conditions the optimal halide/solvent system, given that important differences in reactivity are observed. These differences are ascribed to the change in the rate limiting step depending on the substrate/halide/solvent combinatio