Biaxial testing, histological measurements and theoretical continuum mechanics modeling were employed to investigate the structure and mechanical properties of the mitral valve leaflet-strut chordae transition zone (LCT). The results showed that geometry changes and collagen fiber angle distribution contribute to variations in mechanical properties in the LCT zone. A simple three-coefficient exponential constitutive law was able to simulate the variation in stress-stretch behavior in the LCT zone by spatially varying a single coefficient and incorporating collagen fiber angle and degree of alignment. This quantitative information can greatly improve the predictions from biomechanical valve models by incorporating regional variations of structure and properties in the mitral leaflet-chordae tendineae system. These data provide the foundation for a computational model for studying stress distributions before and following chordal rupture, which may indicate the underlying reasons for the development of valve insufficiency in patients.

The mechanism of direct NO decomposition is different than three-way catalysis and depends on temperature and pretreatment environment over PdO/SiO2.

Multicomponent alloys and oxides are material systems, offering the great promise of unique yet advantageous catalytic properties through appropriate choice of compositions. However, strategic design of the highly active multicomponent catalyst is challenged by the vast number of potential candidates and complex inter-component effects. Herein, we demonstrate the successful employment of Bayesian optimization (BO) to improve the experimental measured activity as a direct function of compositional variables without educating physical knowledge to the machine. We applied BO in screening spinel Cr a Mn b Fe c Co d Ni e Cu f Zn 3−a−b−c−d−e−f O 4 for the decomposition of nitric oxide into environmentally friendly nitrogen.Starting with 30 manually surveyed samples, 35 more samples were measured, and six oxides were discovered with higher specific activities. The best candidate discovered in the current work, Co 2.1 Cu 0.6 Zn 0.2 Mn 0.1 O 4 , showed significantly better catalytic performance than the benchmark standard. Although not directly educated about the underlying physical origin of variation in specific activity, the optimization balanced the exploration to locate promising regions and exploitation to survey in the identified region of Mn-containing subspace. The success to directly optimize the experimental measured specific activity in the large compositional space through a small sampled data set demonstrates the great potential of BO in the discovery and design of multicomponent catalysts.

The use of multiple interfaces to access heterogeneous networks is becoming a strong reality to end-users. Hence one realistic problem is how to select a specific access interface (and consequently network) as well as how to perform smooth and seamless handover among different types of technologies. In this paper we propose a dynamic and user-centric network selection and decision process which optimizes handover across heterogeneous networks. A Satisfaction Degree Function (SDF) is used to evaluate, according to user's predefined criteria, available networks and select the best one(s) according to such criteria. The criteria consider incorporating user policies and information from several OSI Layers, including dynamic network status and application requirements. Numerical results show that the proposed network selection process results in the choice of the best network according to the user's choices.

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The catalytic asymmetric synthesis of mono-fluoro-, -chloro- and -bromomethyl-1,2-diaryl ester cyclopropanes is described.

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Submicrosized alloy cables of ZnO/w-ZnS(1-x)Se(x) (0 < x < 1) and ZnO/s-ZnSe(1-x)Te(x) (0.8 < or = x < 1) have been prepared. The lattice parameters of the sheath show linear compositional dependence following Vegard's law. The composition-band gap dependence follows the trend of E(g)(ZnO/w-ZnS(1-x)Se(x))(x) = 3.60 - 1.77x + 0.87x(2) (0.22 < or = x < or = 1), E(g)(ZnO/w-ZnS(1-x)Se(x)) = 3.25 eV (0 < or = x < or = 0.22), and E(g)(ZnO/s-ZnSe(1-x)Te(x))(x) = 2.65 - 1.82x + 1.41x(2) (0 < or = x < or = 1), respectively. The continuous band-gap modulations on ZnO-based heterostructures are associated with the core/sheath morphology and the nature of the sheath alloys.