Wake dynamics of external flow past a curved circular cylinder with the free stream aligned with the plane of curvature

Accepted versio

Role of the 5' untranslated region of the Alfalfa mosaic virus RNA 3 in cell-to-cell and long distance transport.

Após o início da infecção de uma única célula, vírus de planta necessita para invadir as células adjacentes, uma processo de transporte de célula-a-célula denominados, como um passo anterior para invadir as partes distais do hospedeiro através do sistema vascular ou do transporte sistémico. A capacidade para atingir as partes não inoculadas de um planta implica que o vírus deve infectar específico células localizadas no tecido vascular. Na maioria dos casos, partículas do vírus são necessários para este trans- vascular port. No presente estudo, tratamos o caracterização de determinantes virais críticos para o transporte de longa distância usando o Alfalfa vírus do mosaico (AMV) sistema de modelo, o que exige partícula do vírus para o transporte sistêmicaEdição dos Resumos do 12º Congreso Nacional de Virología, Burgos, Espanha, jun. 2013

Psychological climate, sickness absence and gender

We examined whether the relationship between psychological climate and sickness absence is moderated by gender. We expected that this relationship would be stronger among men than among women. We tested this general hypothesis using two samples of men and women nurses (made up of 114 and 189 subjects, respectively). The results obtained supported our expectation. The three climate facets considered (support, goals orientation and rules orientation) showed a significant relationship with sickness absence in the men sample, but not in the women sample. Clima psicológico, absentismo y género. Se investigó si la relación entre clima psicológico y absentismo por enfermedad está moderada por el género de los empleados. Se esperaba que la relación fuera más fuerte en hombres que en mujeres. Esta hipótesis general se puso a prueba utilizando dos muestras de enfermeros/as formadas por 114 varones y 189 mujeres. Los resultados obtenidos respaldaron nuestra hipótesis general. Las tres dimensiones de clima consideradas (apoyo, orientación hacia objetivos y orientación hacia reglas) mostraron una relación estadísticamente significativa con absentismo en la muestra de varones, pero no en la de mujeres

Modelling Long-Term Urban Temperatures with Less Training Data: A Comparative Study Using Neural Networks in the City of Madrid

In the last decades, urban climate researchers have highlighted the need for a reliable provision of meteorological data in the local urban context. Several efforts have been made in this direction using Artificial Neural Networks (ANN), demonstrating that they are an accurate alternative to numerical approaches when modelling large time series. However, existing approaches are varied, and it is unclear how much data are needed to train them. This study explores whether the need for training data can be reduced without overly compromising model accuracy, and if model reliability can be increased by selecting the UHI intensity as the main model output instead of air temperature. These two approaches were compared using a common ANN configuration and under different data availability scenarios. Results show that reducing the training dataset from 12 to 9 or even 6 months would still produce reliable results, particularly if the UHI intensity is used. The latter proved to be more effective than the temperature approach under most training scenarios, with an average RMSE improvement of 16.4% when using only 3 months of data. These findings have important implications for urban climate research as they can potentially reduce the duration and cost of field measurement campaigns

An analysis on the impact and detection of kernel stack infoleaks

This is a pre-copyedited, author-produced PDF of an article accepted for publication in Logic Journal of the IGPL following peer review. The version of record An analysis on the impact and detection of kernel stack infoleaks. Logic Journal of the IGPL, 24(6), 899-915. is available online at: https://academic.oup.com/jigpal/issue/24/6.[EN] The Linux kernel has become a fundamental component of mainstream computing solutions, now being used in a wide range of applications ranging from consumer electronics to cloud and server solutions. Being expected to continue its growth, especially in the mission-critical workloads. Parallel to the Linux adoption has increased its misuse by attackers and malicious users. This has increased attention paid to kernel security through the deployment of kernel protection mechanisms. Kernel-based attacks require reliability, where kernel attack reliability is achieved through the information gathering stage, where the attacker is able to gather enough information about the target to succeed. The taxonomy of kernel vulnerabilities includes information leaks (CWE-200), that are a class of vulnerabilities that permit access to the kernel memory layout and contents. Information leaks can improve the attack reliability enabling the attacker to read sensitive kernel data to bypass kernel based protections. In this work, we aim at the analysis and detection of stack-based information leaks to harden the security of the kernel. First, we analyse the problem of kernel infoleaks in Section 3, next, we examine the impact of infoleaks attacks on the security of the kernel in Section 4. Then, we present a technique for detecting kernel based infoleaks through static analysis Section 5. Next, we evaluate our technique by applying it to the Linux kernel in Section 6. Finally, we discuss the applications and limitations of our work (Section 6.3) and finally we draw our concluding remarks.The author wants to thank all the people that contributed to make this work possible. This work has been partially supported by the Spanish Government Research Office under grant TIN2014-56158-C4-1-P, TIN2014-56158-C4-4-P and EU Project DREAMS FP7-ICT- 610640.Peiró Frasquet, S.; Muñoz Alcobendas, M.; Crespo Lorente, A. (2016). An analysis on the impact and detection of kernel stack infoleaks. Logic Journal of the IGPL. 24(6):899-915. https://doi.org/10.1093/jigpal/jzw049S89991524

Luminescence properties of Ce3+ and Tb3+ co-doped SiOxNy thin films: Prospects for color tunability in silicon-based hosts

In this work, the role of the nitrogen content, the annealing temperature, and the sample morphology on the luminescence properties of Ce3+ and Tb3+ co-doped SiOxNy thin films has been investigated. An increasing nitrogen atomic percentage has been incorporated in the host matrix by gradually replacing oxygen with nitrogen during fabrication while maintaining the Si content unaltered, obtaining a sequential variation in the film composition from nearly stoichiometric SiO2 to SiOxNy. The study of rare earth doped single layers has allowed us to identify the parameters that yield an optimum optical performance from Ce3+ and Tb3+ ions. Ce3+ ions proved to be highly sensitive to the annealing temperature and the nitrogen content, showing strong PL emission for relatively low nitrogen contents (from 0 to 20%) and moderate annealing temperatures (800-1000 degrees C) or under high temperature annealing (1180 degrees C). Tb3+ ions, on the other hand, displayed a mild dependence on those film parameters. Rare earth co-doping has also been investigated by comparing the luminescence properties of three different approaches: (i) a Ce3+ and Tb3+ co-doped SiOxNy single layer, (ii) a bilayer composed of two SiOxNy single layers doped with either Ce3+ or Tb3+ ions, and (iii) a multilayer composed of a series of either Tb3+ or Ce3+-doped SiOxNy thin films with interleaved SiO2 spacers. Bright green emission and efficient energy transfer from either Ce3+ ions or Ce silicates to Tb3+ ions has been observed in the co-doped single layer as a consequence of the strong ion-ion interaction. On the other hand, independent luminescence from Ce3+ and Tb3+ ions has been observed in the Ce3+ and Tb3+ co-doped bilayer and multilayer, providing a good scenario to develop light emitting devices with wide color tunability by varying the number of deposited films that contain each rare earth dopant. Moreover, the optoelectronic properties of Ce3+-and/or Tb3+-doped thin films have been studied by depositing transparent conductive electrodes over selected samples. An electroluminescence signal according to the rare earth transitions is obtained in all cases, validating the excitation of Ce3+ and Tb3+ ions upon electron injection. Also, the main charge transport of injected electrons has been evaluated and correlated with the layer stoichiometry. Finally, a simple reliability test has allowed disclosing the origin of the early breakdown of test devices, attributed to the excessive joule heating at filament currents that occur around a region close to the polarization point. (C) 2016 AIP Publishing LLC.This research was supported by the Spanish Ministry of Science and Innovation (TEC2012-38540-C02-01). RBS characterization was performed in the Tandetron Accelerator Laboratory at Western University in London, ON (Canada). TEM characterization was carried out in the Science and Technical Centers (CCiT) of the University of Barcelona. In Canada, this work was supported by the Natural Sciences and Engineering Research Council (NSERC) under the Discovery Grants program.Ramirez, JM.; Ruiz-Caridad, A.; Wojcik, J.; Gutiérrez Campo, AM.; Estrade, S.; Peiro, F.; Sanchis Kilders, P.... (2016). Luminescence properties of Ce3+ and Tb3+ co-doped SiOxNy thin films: Prospects for color tunability in silicon-based hosts. Journal of Applied Physics. 119(11):113108-1-113108-14. https://doi.org/10.1063/1.4944433S113108-1113108-141191

Investigation of defect formation and electronic transport in microcrystalline silicon deposited by hot-wire CVD

We have investigated doped and undoped layers of microcrystalline silicon prepared by hot-wire chemical vapour deposition optically, electrically and by means of transmission electron microscopy. Besides needle-like crystals grown perpendicular to the substrate's surface, all of the layers contained a noncrystalline phase with a volume fraction between 4% and 25%. A high oxygen content of several per cent in the porous phase was detected by electron energy loss spectrometry. Deep-level transient spectroscopy of the crystals suggests that the concentration of electrically active defects is less than 1% of the undoped background concentration of typically 10^17 cm -3. Frequency-dependent measurements of the conductance and capacitance perpendicular to the substrate surface showed that a hopping process takes place within the noncrystalline phase parallel to the conduction in the crystals. The parasitic contribution to the electrical circuit arising from the porous phase is believed to be an important loss mechanism in the output of a pin-structured photovoltaic solar cell deposited by hot-wire CVD