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The short-time Fourier transform is applied to analyze the backscattered signal from a coated strip with a gap in the coating. The resulting time-frequency display shows good localization of the different scattering mechanisms. In particular, the time-frequency representation is well suited for identifying the dispersive surface wave contributions. The different scattering mechanisms are further extracted by applying two-dimensional gates in the time-frequency plane. This is a natural extension of the usual time-gating concept and allows the original data to be decomposed into a set of fundamental scattering mechanisms in either the time or the frequency domain.

We analyse the solution of the linear advection equation on a uniform mesh by a non dissipative second order scheme for discontinuous initial condition. These schemes are known to generate parasitic oscillations in the vicinity of the discontinuity. An approximate way to predict these oscillations is provided by the equivalent equation method. More specifically, we focus on the case of advection of a step function by the leapfrog scheme. Numerical experiments show that the equivalent equation method fails to reproduce the oscillations generated by the scheme far from the discontinuity. Thus, we derive closed form exact and approximate solutions for the scheme that accurately predict these oscillations. We study the relationship between equivalent equation approximation and exact solution for the scheme, to determine its range of validity. [ABSTRACT FROM AUTHOR]

Background: Premature skin aging results from exposure to a range of environmental factors, primarily ultraviolet radiation, but also high-energy visible light in the blue spectrum, infrared radiation, and environmental pollution. These extrinsic factors result in the generation of reactive oxygen species which promote photoaging and DNA damage resulting in skin cancers., Aims: To formulate skincare products utilizing a new coating applied to zinc oxide and titanium dioxide particles and complimentary skincare ingredients to provide broad protection against a range of environmental insults., Methods: A cross-polymer, multifunctional coating of silicate, polyalkylsilsesquioxane, and polydimethylsiloxane moieties increases the photostability and decreases the reactivity of mineral sunscreen agents when interacting with energy sources. These products are also formulated with antioxidants to minimize free radical propagation. Additionally, this coating improves the esthetic feel of mineral sunscreens, while the appearance is enhanced by formulating products with a blend of iron oxides., Results: A series of in vitro and ex vivo studies demonstrated the ability of mineral-based products formulated with the new multifunctional coating to provide protection against ultraviolet radiation, high-energy visible light, infrared radiation, and environmental pollution., Conclusion: Newly formulated mineral-based skincare products provide environmental protection, are ecologically safe, and can replace chemical-based sunscreen ingredients., (© 2019 The Authors. Journal of Cosmetic Dermatology Published by Wiley Periodicals, Inc.)

This paper considers a class of low-order, range-dependent propagation models obtained from the normal mode decomposition of infrasounds in complex atmospheres. The classical normal mode method requires calculating eigenvalues for large matrices making the computation expensive even though some modes have little influence on the numerically obtained results. By decomposing atmospheric perturbations into a wavelet basis, it is shown that the most sensitive eigenvalues provide the best reduced model for infrasound propagation. These eigenvalues lie on specific curves in the complex plane that can be directly deduced from atmospheric data through a WKB approach. The computation cost can be reduced by computing the invariant subspace associated with the most sensitive eigenvalues. The reduction method is illustrated in the case of the Fukushima explosion (12 March 2011). The implicitly restarted Arnoldi algorithm is used to compute the three most sensitive modes, and the correct tropospheric arrival is found with a cost of 2% of the total run time. The cost can be further reduced by using a stationary phase technique. Finally, it is shown that adding uncertainties triggers a stratospheric arrival even though the classical criteria, based on the ratio of stratospheric sound speed to that at ground level, is not satisfied.

Heme oxygenase 1 (HO-1) is an enzyme which degrades heme into tree end products: biliverdin, free iron and carbon monoxide. This enzyme has recently been shown to have anti-inflammatory and tissue protective effects. HO-1 expression is involved in organ protection in pathological situations, and immunosuppressive treatments resulting in indefinite graft survival without chronic rejection have been associated with HO-1 expression by cells of the vessel wall. The aim of this study was to analyze the effect of specific HO-1 overexpression. We used a recombinant adenovirus coding for human HO-1 cDNA in a rat aorta chronic rejection model, 30 days after transplantation. Control groups included rats non treated or treated with a non-coding adenovirus Addl324. We first demonstrated that AdHO-1 was efficiently expressed in endothelial cells in vitro, and in rat aortas ex vivo after adenovirus gene transfer. We found that intimal thickening in AdHO-1 treated aortas (10.8 +/- 3.8%, n=5) was significantly decreased compared to untreated (21.2 +/- 5.6%, n = 5) or Addl324-treated (21.1 +/- 1.2%, n = 4) aortas. Immunohistology showed that treatment with AdHO-1 resulted in a significant reduction in leukocyte infiltration and a decreasing number of VSMC in the intima, compared to Addl324-treated aortas. However, this effect of HO-1 on chronic rejection did not imply modifications on numbers of apoptotic cells in the graft or of alloantibody levels. We have demonstrated, for the first time, that specific HO-1 overexpression following gene transfer of HO-1 inhibited chronic rejection by reducing leukocyte and VSMC infiltration of the aorta intima.