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In this paper, we present a comprehensive probabilistic analysis of the deflection of a static cantilever beam based on Euler–Bernoulli's theory. For the sake of generality in our stochastic study, we assume that all model parameters (Young's modulus and the beam moment of inertia) are random variables with arbitrary probability densities, while the loads applied on the beam are described via a delta-correlated process. The probabilistic study is based on the calculation of the first probability density function of the solution and the probability density of other key quantities of interest, such as the shear force, and the bending moment, which are treated as random variables too. To conduct our study, we will first calculate the first moments of the solution, which is a stochastic process, and we then will take advantage of the Principle of Maximum Entropy. Furthermore, we will present an algorithm, based on Monte Carlo simulations, that allows us to simulate our analytical development computationally. The theoretical findings will be illustrated with numerical examples where different realistic probability distributions are assumed for each model random parameter. [ABSTRACT FROM AUTHOR]

In this paper, a computational technique to deal with uncertainty in dynamic continuous models in Social Sciences is presented. Considering data from surveys, the method consists of determining the probability distribution of the survey output and this allows to sample data and fit the model to the sampled data using a goodness-of-fit criterion based on the χ 2 -test. Taking the fitted parameters that were not rejected by the χ 2 -test, substituting them into the model and computing their outputs, 95% confidence intervals in each time instant capturing the uncertainty of the survey data (probabilistic estimation) is built. Using the same set of obtained model parameters, a prediction over the next few years with 95% confidence intervals (probabilistic prediction) is also provided. This technique is applied to a dynamic social model describing the evolution of the attitude of the Basque Country population towards the revolutionary organisation ETA. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the construction of random power series solution of vector initial value problems containing uncertainty in both initial condition and source term. Under appropriate hypothesis on the data, we prove that the random series solution constructed by a random Fröbenius method is convergent in the mean square sense. Also, the main statistical functions of the approximating stochastic process solution generated by truncation of the exact series solution are given. Finally, we apply the proposed technique to several illustrative examples. [Copyright &y& Elsevier]

Abstract: This paper compares and discusses the efficiency of various air curtains designed to ultimately operate a bilateral aeraulic confinement of a short section of a tunnel or corridor-like geometry. The tested arrangements include single- and twin-jet air curtain systems with and without air return ducts. Jet opening ratios equal to 10 and 20 are considered, with air discharge velocities ranging from 1 to 10m/s. The facility and the experimental approach used in this work are described and justified in many details. Results are presented in terms of leakage flow rates. Information is also provided about relevant air change rates and system time constants. The global efficiency of an air curtain is greatly improved by the adjunction of an air recirculation circuit due to enhanced system stability. A critical jet exit velocity corresponding to transition from the laminar to the turbulent regime of the channel flow inside the air curtain diffuser was found. For discharge velocities larger than this critical velocity an asymptotic behaviour is observed for every air curtain tested. At the lower nozzle exit velocities, the non-recirculated twin-jet system exhibits a weird behaviour. Unexpectedly, the results show that a single jet with a given opening ratio may perform better than a twin-jet of same height with a lower opening ratio. However, the results show that the performance of an air curtain is much dependant of the conditions under which this air curtain is operated demonstrating therefore that great care should be exercised in any attempt of comparison. [Copyright &y& Elsevier]

[Display omitted] • Use of delaminated clays as catalysts for hydrocarbon hydroconversion. • Influence of acidic and reductive properties of catalysts. • XPS study of the sulfide phases of NiMo and NiW. • Conversion and selectivity study in 1-methylnaphtalene hydrocracking. A series of catalysts was synthesized using two delaminated mesoporous Colombian clays as supports (vermiculite and bentonite), and incorporating NiMo and NiW as active species, taking advantage of their acidic and mesoporous properties to be used in hydroconversion of hydrocarbons. The synthesized solids were characterized by N 2 physisorption, temperature programmed reduction (TPR-H 2), diffuse reflectance infrared spectroscopy using NH 3 as the probe molecule (DRIFT), temperature programmed desorption (TPD-NH 3) and X-ray photoelectron spectroscopy (XPS). These catalysts were evaluated in the hydrocracking of 1-methyl naphthalene (HCK 1MN), finding that the catalyst with NiMo as its active phase supported on delaminated vermiculite, presents the best catalytic performance, associated, among others, with the important formation of the NiMoS sulfided phase, detected by XPS. [ABSTRACT FROM AUTHOR]

In the past three decades invasive mycoses have globally emerged as a persistent source of healthcare-associated infections. The cell wall surrounding the fungal cell opposes the turgor pressure that otherwise could produce cell lysis. Thus, the cell wall is essential for maintaining fungal cell shape and integrity. Given that this structure is absent in host mammalian cells, it stands as an important target when developing selective compounds for the treatment of fungal infections. Consequently, treatment with echinocandins, a family of antifungal agents that specifically inhibits the biosynthesis of cell wall (1-3)β-D-glucan, has been established as an alternative and effective antifungal therapy. However, the existence of many pathogenic fungi resistant to single or multiple antifungal families, together with the limited arsenal of available antifungal compounds, critically affects the effectiveness of treatments against these life-threatening infections. Thus, new antifungal therapies are required. Here we review the fungal cell wall and its relevance in biotechnology as a target for the development of new antifungal compounds, disclosing the most promising cell wall inhibitors that are currently in experimental or clinical development for the treatment of some invasive mycoses. [ABSTRACT FROM AUTHOR]

Abstract: Respiratory Syncytial Virus (RSV) has long been recognized as the single most important virus causing acute severe respiratory-tract infections with symptoms ranging from rhinitis to bronchitis in children who may require hospitalization. Outbreaks of RSV occur every year and all children become infected within the first two years of life, and that overloads hospital casualty services. The transmission dynamics of RSV are strongly seasonal. Epidemics occur each winter in temperate climates and often coincide with the seasonal rainfall in tropical climates. In this paper we develop a non-standard numerical scheme for a SIRS seasonal epidemiological model for RSV transmission. This non-standard numerical scheme preserves the positivity of the continuous model and is applied to approximate the solution using different sizes of step. Finally this method is compared with some well-known explicit methods and simulations with data from Gambia and Finland are carried out. [Copyright &y& Elsevier]

Abstract: The task of breast density quantification is becoming increasingly relevant due to its association with breast cancer risk. In this work, a semi-automated and a fully automated tools to assess breast density from full-field digitized mammograms are presented. The first tool is based on a supervised interactive thresholding procedure for segmenting dense from fatty tissue and is used with a twofold goal: for assessing mammographic density (MD) in a more objective and accurate way than via visual-based methods and for labeling the mammograms that are later employed to train the fully automated tool. Although most automated methods rely on supervised approaches based on a global labeling of the mammogram, the proposed method relies on pixel-level labeling, allowing better tissue classification and density measurement on a continuous scale. The fully automated method presented combines a classification scheme based on local features and thresholding operations that improve the performance of the classifier. A dataset of 655 mammograms was used to test the concordance of both approaches in measuring MD. Three expert radiologists measured MD in each of the mammograms using the semi-automated tool (DM-Scan). It was then measured by the fully automated system and the correlation between both methods was computed. The relation between MD and breast cancer was then analyzed using a case–control dataset consisting of 230 mammograms. The Intraclass Correlation Coefficient (ICC) was used to compute reliability among raters and between techniques. The results obtained showed an average ICC=0.922 among raters when using the semi-automated tool, whilst the average correlation between the semi-automated and automated measures was ICC=0.838. In the case–control study, the results obtained showed Odds Ratios (OR) of 1.38 and 1.50 per 10% increase in MD when using the semi-automated and fully automated approaches respectively. It can therefore be concluded that the automated and semi-automated MD assessments present a good correlation. Both the methods also found an association between MD and breast cancer risk, which warrants the proposed tools for breast cancer risk prediction and clinical decision making. A full version of the DM-Scan is freely available. [Copyright &y& Elsevier]