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11.
We have used two dimensional drift diffusion simulations to calculate the electrical properties of bottom contact pentacene based organic thin film transistor, taking into account field-dependent mobility and interface or bulk trap states. In order to derive from basic principles the transport properties of the organic semiconductor we have developed a Monte Carlo simulator to calculate the field dependent mobility. We analyzed the presence of trap states at the interface between organic material and gate insulator and we show the influence of trap states combined with the effect of field-dependent mobility on the transfer characteristic. Numerical calculations are also reported for the output characteristics of the device showing a very good agreement with the available experimental results.  相似文献   
12.
The previous on-line LC-GC method for the direct analysis of the minor components in oils and fats (without cleavage of esters) was modified: The free alcohols/sterols were silylated instead of acylated, and the LC fraction transferred to GC is widened to range from the beginning of the LC chromatogram up to the sterol esters. Silylation eliminated the problem that acylation may esterify some free alcohols with free fatty acids from the oil if the oil or fat is of high acidity. Widening of the LC fraction to include squalene and the tocopherols added information to that previously obtained.  相似文献   
13.
The computational method for large deformation plasticity called differential equations on a manifold (DEM) has previously been shown to be effective for axisymmetric and plane strain sheet metal forming problems. The method has now been formulated for in-plane stretching problems, incorporated into a computer code, and applied to several problems. The code's performance is robust and accurate, as evidenced by a comparison with other published results. Incorporation of an automatic mesh generator significantly reduces data preparation time.  相似文献   
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15.
This paper concerns several analytical problems related to linear polyhedra in euclidean three-dimensional-space. Symbolic formulas for line, surface, and volume integration are given, and it is shown that domain integrals are computable in polynomial time. In particular, it is shown that mass, first and second moments, and products of inertia are computable inO(E) time, whereE is the number of edges of the boundary. Simple symbolic expressions for the normal derivatives of domain integrals are also derived. In particular, it is shown that they are closely linked to the topology of the integration domain, as well as that they are expressible as combinations of domain integrals over lower-order domains (faces, edges, and vertices). The symbolic results presented in this paper may lead to an easy incorporation of integral constraints, for example, concerning mass and inertia, in the engineering designing process of solid objects.  相似文献   
16.
Under the hypothesis that cardioprotective agents might benefit from synergism between antiarrhythmic activity and antioxidant properties, a small series of mexiletine analogues were coupled with the 2,2,5,5-tetramethylpyrroline moiety, known for its antioxidant effect, in order to obtain dual-acting drugs potentially useful in the protection of the heart against post-ischemic reperfusion injury. The pyrroline derivatives reported herein were found to be more potent as antiarrhythmic agents than mexiletine and displayed antioxidant activity. The most interesting tetramethylpyrroline congener, a tert-butyl-substituted analogue, was at least 100 times more active as an antiarrhythmic than mexiletine.  相似文献   
17.
Lipofilling (LF) is a largely employed technique in reconstructive and esthetic breast surgery. Over the years, it has demonstrated to be extremely useful for treatment of soft tissue defects after demolitive or conservative breast cancer surgery and different procedures have been developed to improve the survival of transplanted fat graft. The regenerative potential of LF is attributed to the multipotent stem cells found in large quantity in adipose tissue. However, a growing body of pre-clinical evidence shows that adipocytes and adipose-derived stromal cells may have pro-tumorigenic potential. Despite no clear indication from clinical studies has demonstrated an increased risk of cancer recurrence upon LF, these observations challenge the oncologic safety of the procedure. This review aims to provide an updated overview of both the clinical and the pre-clinical indications to the suitability and safety of LF in breast oncological surgery. Cellular and molecular players in the crosstalk between adipose tissue and cancer are described, and heterogeneous contradictory results are discussed, highlighting that important issues still remain to be solved to get a clear understanding of LF safety in breast cancer patients.  相似文献   
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A molecular distillation plant, built particularly to increase the separation efficiency and to obtain safer working conditions, was tested to remove cholesterol from anhydrous butter and lard. A preliminary experiment was carried out with butter to evaluate the fractionation obtained at temperatures between 190 and 250°C and residual pressures between 10−3 and 10−4 torr. A second experiment was carried out at 185°C and at the maximum operational vacuum, evaluating the fractionation achieved within a time scale between 30 and 180 min. Cholesterol was almost completely removed during the second hour with minimal loss of low-molecular weight triglycerides. An experiment was carried out with lard at 250°C and maximum achievable operational vacuum (10−4 Torr), lasting approximately 6 h, and cholesterol was removed almost completely during the second hour without significant modifications in the triglyceride composition. This situation remained constant throughout the duration of the test.  相似文献   
20.
Software development processes have been evolving from rigid, pre-specified, and sequential to incremental, and iterative. This evolution has been dictated by the need to accommodate evolving user requirements and reduce the delay between design decision and feedback from users. Formal verification techniques, however, have largely ignored this evolution and even when they made enormous improvements and found significant uses in practice, like in the case of model checking, they remained confined into the niches of safety-critical systems. Model checking verifies if a system’s model \(\mathcal{M}\) satisfies a set of requirements, formalized as a set of logic properties \(\Phi\) . Current model-checking approaches, however, implicitly rely on the assumption that both the complete model \(\mathcal{M}\) and the whole set of properties \(\Phi\) are fully specified when verification takes place. Very often, however, \(\mathcal{M}\) is subject to change because its development is iterative and its definition evolves through stages of incompleteness, where alternative design decisions are explored, typically to evaluate some quality trade-offs. Evolving systems specifications of this kind ask for novel verification approaches that tolerate incompleteness and support incremental analysis of alternative designs for certain functionalities. This is exactly the focus of this paper, which develops an incremental model-checking approach for evolving Statecharts. Statecharts have been chosen both because they are increasingly used in practice natively support model refinements.  相似文献   
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