Two problematic human polymorphic Alu insertions

Analysis of two previously described polymorphic Alu insertions (Sb19.3 and NBC3) in world-wide human populations generated genotypic frequencies grossly in violation of Hardy-Weinberg equilibrium expectations. GenBank searches at the National Center for Biotechnology Information (NCBI) and sequencing analyses revealed that samples homozygous for the Sb19.3 Alu insertion amplify a band indistinguishable in size to the lack of insertion amplicon, corresponding to a paralogous locus on chromosome 4. This locus displays a very similar sequence (84%) to that flanking the Sb19.3 Alu insertion located at chromosome 19. Moreover, we have determined that NBC3, a different Alu insertion, is not located in the pseudoautosomal region of the Y-chromosome, as previously reported, but in position Yq11.2. Also, the band that mimics the lack of insertion amplicon corresponds to a paralogous locus located at chromosome X with a similarity of 92% to the sequence flanking the NBC3 Alu insertion. Finally, the utilization of newly designed primers avoided amplification from the paralogous loci and allowed a reliable assignation of genotypes for both loci. Unlike previously reported, using our new primers the Y-specific locus NBC3 was found not to be polymorphic in the populations analyzed.     

Crack detection of a double-beam carrying a concentrated mass

This paper presents the influence of a concentrated mass location on the natural frequencies of a cracked double-beam. The double-beam consists of two different beams connected by an elastic medium. The concentrated mass is located on the main beam. The relationship between the natural frequency and the location of concentrated mass is established and called “Frequency–Mass Location” (FML). The numerical simulations show that when there is a crack, the frequency of the double-beam changes irregularly when the concentrated mass is attacked at the crack position. This irregular change can be amplified by the wavelet transform and this is useful for crack detection: the crack location can be detected by the location of peaks in the wavelet transform of the FML. Finite element model for the cracked double-beam carrying a concentrated mass is presented and numerical simulations are also provided.     

Robustness of Pathwise Stability of Semilinear Perturbed Stochastic Evolution Equations

Abstract

The purpose of this paper is to investigate pathwise stability for certain Hilbert space-valued stochastic evolution equations. We are especially interested in the robustness analysis of perturbed stochastic differential equations in infinite dimensions. Sufficient conditions are established to ensure the almost surely stable decay of the given stochastic systems. Lastly, a corollary and corresponding example are studied to illustrate our theory.     

Determination of crack growth kinetics in non-reinforced semi-crystalline thermoplastics using the linear elastic fracture mechanics (LEFM) approach

The aim of this study was to find a satisfactory method to characterize the fatigue crack growth behavior of non-reinforced, semi-crystalline thermoplastic polymers using linear elastic fracture mechanics (LEFM). For this, crack growth curves (crack length versus cycle number) as well as crack growth kinetics curves (crack growth rate da/dN versus amplitude stress intensity factor ΔK) had to be generated. As methods suggested by ISO 15850 and ASTM E 647-11 failed to provide satisfactory results for the crack growth curves, a more advanced method was searched for and finally found in the literature. Regarding the crack growth kinetics curve, the idea of the calculation was based on methods recommended in ISO 15850 and ASTM E 647-11. However, these methods had to be considerably modified and improved in order to get accurate results with little scatter. The whole methodology was developed and verified with fatigue crack growth tests on two semi-crystalline thermoplastics (polyoxymethylene POM and polyetheretherketone PEEK).     

Novel WS2/Fe0.95S1.05 Hierarchical Nanosphere as a Highly Efficient Electrocatalyst for Hydrogen Evolution Reaction

Fe_0.95S_1.05 with high reactivity and stability was incorporated into WS₂ nanosheets via a one-step solvothermal method for the first time. The resulted hybrid catalyst has much higher catalytic activity than WS₂ and Fe_0.95S_1.05 alone, and the optimal WS₂/Fe_0.95S_1.05 hybrid catalyst was found by adjusting the feed ratio. The addition of Fe_0.95S_1.05 was proven to be able to enhance the hydrogen evolution reaction (HER) activity of WS₂, and vice versa. At the same time, it was found that the catalytic effect of the hybrid catalyst was the best when the feed ratio was W : Fe=2 : 1. In other words, we confirmed that there is a synergistic effect between W- and Fe-based sulfide hybrid catalysts, and validated that the reason for the improved HER performance is the strong interaction between the two in the middle sulfur. WS₂/Fe_0.95S_1.05-2 hybrid catalyst leads to enhanced HER activity, which shows a low overpotential of ∼0.172 V at 10 mA cm⁻², low Tafel slope of ∼53.47 mV/decade. This study supplies innovative synthesis of a highly active WS₂/Fe_0.95S_1.05 hybrid catalyst for HER.     

Evolution of downsized crescent-shaped dune in wind tunnel experiment

The migration of a downsized crescent-shaped dune was investigated in a wind tunnel experiment.Quantified upwind influx and vertical oscillation of the sand bed were introduced to modulate the saturation level of the sand flux above the dune surface to affect dune evolution.The evolution was recorded by top-view photography and then abstracted as the evolution of self-defined characteristic quantities using a digital image processing algorithm.The results showed that,in contrast to the case for spanwise quantities,the evolution of streamwise quantities corresponds to a linear increase in the modulation magnitude more positively and in a monotonic and convergent manner.In contrast with quantities on the windward face,the changes in quantities with respect to the horns were nonmonotonic with time and almost uncorrelated with the variation in modulation strength,which reveals the distinctiveness of leeside evolution.     

Local existence-uniqueness and continuation of solutions for delay stochastic evolution equations

In this article, we consider dynamic behaviours of a class of non-linear delay stochastic evolution equations. Local existence and uniqueness of the solutions are obtained with the aid of proper iterative scheme and moment estimations. We also propose a continuation result and our results generalize the known results.