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Inventory problems generally have a structure that can be exploited for computational purposes. Here, we look at the duals of two seemingly unrelated inventory models that suggest an interesting duality between discrete time optimal control and optimization over an ordered sequence of variables. Concepts from conjugate duality and generalized geometric programming are used to establish the duality.  相似文献   
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Summary It is shown how a self-organizing neural network such as the one introduced by Kohonen can be used to analyze features of molecular surfaces, such as shape and the molecular electrostatic potential. On the one hand, two-dimensional maps of molecular surface properties can be generated and used for the comparison of a set of molecules. On the other hand, the surface geometry of one molecule can be stored in a network and this network can be used as a template for the analysis of the shape of various other molecules. The application of these techniques to a series of steroids exhibiting a range of binding activities to the corticosteroid-binding globulin receptor allows one to pinpoint the essential features necessary for biological activity.  相似文献   
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Allergies to peanuts are becoming an increasingly important health problem as a result of the persistence and severity of the reaction in allergic individuals. Because no treatment currently is available, avoidance is the only option for peanut-allergic individuals. Avoidance of an abundant and often disguised food such as peanuts, however, is very difficult; therefore, competitive inhibition ELISAs were developed to detect and quantitate each of the major peanut allergens, Ara h 1 and Ara h 2. Under optimal conditions for each assay, the sensitivity of the Ara h 1 and Ara h 2 detection assays were 12 and 0.5 ng/mL, respectively. These assays were primarily devised to effectively compare the levels of Ara h 1 and Ara h 2 in a wide variety of peanuts or peanut products but can also be used to identify cross-reactive antigens. The method is simple and rapid, requiring only one allergen-specific antibody and, therefore, could be adapted specifically to detect the presence of these individual allergens in different foods.  相似文献   
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A copper(II) complex containing the ceftobiprole drug and 1,10-phenanthroline (phen) has been synthesized and characterized by UV–vis, FT-IR and mass spectra, and elemental analysis. The binding interaction between [Cu(cef)(phen)Cl2] complex and human serum albumin (HSA) was investigated using absorption, fluorescence emission and circular dichroism spectroscopies, and molecular docking. Thermodynamic parameters (ΔH < 0 and ΔS < 0) indicated that the hydrogen bond and van der Waals interactions played main roles in the binding of complex [Cu(cef)(phen)Cl2] to HSA. The results of CD and UV–vis spectroscopy showed that the binding of [Cu(cef)(phen)Cl2] to HSA induces some conformational changes in HSA. Displacement experiments predicted that the binding of [Cu(cef)(phen)Cl2] complex to HSA is located within domain III, Sudlow’s site 2, and these observations were substantiated by molecular docking studies.  相似文献   
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Synthesis and Crystal Structure of the Mixed Valent Complex [Sn2I3(NPPh3)3] The mixed valent phosphoraneiminato complex [Sn2I3(NPPh3)3] ( 1 ) was prepared by the reaction of the tin(II) complex [SnI(NPPh3)]2 with sodium in tetrahydrofuran. 1 crystallizes with two formula units of THF to form yellow, moisture sensitive single crystals, which were characterized by a crystal structure determination. 1 · 2 THF: Space group P21/c, Z = 4, lattice dimensions at –80 °C: a = 1964.5(2), b = 1766.0(2), c = 2058.6(2) pm; β = 118.33(1)°, R = 0.052. 1 forms dimeric molecules in which the tin atoms are linked by two nitrogen atoms of two (NPPh3) groups to form a planar Sn2N2 four‐membered ring. The SnIV atom is additionally coordinated by a terminal iodine atom and by a terminal (NPPh3) group, whereas the SnII atom is additionally coordinated by two iodine atoms forming a ψ trigonal‐bipyramidal surrounding.  相似文献   
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