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41.
We construct degenerations of Mukai varieties and linear sections thereof to special unobstructed Fano Stanley–Reisner schemes corresponding to convex deltahedra. This can be used to find toric degenerations of rank one index one Fano threefolds. Furthermore, we show that the Stanley–Reisner ring of the boundary complex of the dual polytope of the associahedron has trivial \(T^2\) . This can be used to find new toric degenerations of linear sections of \(G(2,n)\) . 相似文献
42.
Siegfried E. Drewes Owen L. Njamela Neville D. Emslie Niyum Ramesar John S. Field 《合成通讯》2013,43(20):2807-2815
The acrylate ester of salicylaldehyde, in the presence of DABCO, affords a crystalline coumarin salt. Formation of this derivative confirms a vital intermediate in the mechanism of the reaction. Salicylaldehyde, suitably protected, reacts with methyl acrylate to afford a novel coumarin not unlike the vasodilator chromonar. 相似文献
43.
Recent progress in biopolymer nanoparticle and microparticle formation by heat-treating electrostatic protein-polysaccharide complexes 总被引:1,自引:0,他引:1
Functional biopolymer nanoparticles or microparticles can be formed by heat treatment of globular protein-ionic polysaccharide electrostatic complexes under appropriate solution conditions. These biopolymer particles can be used as encapsulation and delivery systems, fat mimetics, lightening agents, or texture modifiers. This review highlights recent progress in the design and fabrication of biopolymer particles based on heating globular protein-ionic polysaccharide complexes above the thermal denaturation temperature of the proteins. The influence of biopolymer type, protein-polysaccharide ratio, pH, ionic strength, and thermal history on the characteristics of the biopolymer particles formed is reviewed. Our current understanding of the underlying physicochemical mechanisms of particle formation and properties is given. The information provided in this review should facilitate the rational design of biopolymer particles with specific physicochemical and functional attributes, as well as stimulate further research in identifying the physicochemical origin of particle formation. 相似文献
44.
Lpez Susana Owen Guillermo Saboya Martha 《Central European Journal of Operations Research》2022,30(3):837-859
Central European Journal of Operations Research - Standard approaches to model interaction networks are limited in their capacity to describe the nuances of real communication. We present a game... 相似文献
45.
Background
The neuronal endoplasmic reticulum (ER) is an extensive, complex endomembrane system, containing Ca2+ pumps, and Ca2+ channels that permit it to act as a dynamic calcium store. Currently, there is controversy over the continuity of the ER in neurones, how this intersects with calcium signalling and the possibility of physical compartmentalisation. Unfortunately, available probes of ER structure such as vital dyes are limited by their membrane specificity. The introduction of ER-targeted GFP plasmids has been a considerable step forward, but these are difficult to express in neurones through conventional transfection approaches. To circumvent such problems we have engineered a novel ER-targeted GFP construct, termed pIN-KDEL, into a 3rd generation replication-defective, self-inactivating lentiviral vector system capable of mediating gene transduction in diverse dividing and post-mitotic mammalian cells, including neurones. 相似文献46.
Strongin B Bofill J Friedman JI Fuess S Goodman MC Kendall HW Kistiakowsky V Lyons T Osborne LS Pitt R Schneekloth U Taylor FE Bogert D Koizumi G Stutte L Abolins M Brock R Cobau W Hatcher R Owen D Perkins G Tartaglia M Weerts H Belusevic R Walker JK White A Womersley J 《Physical review D: Particles and fields》1991,43(9):2778-2786
47.
Terence C. Owen 《Journal of heterocyclic chemistry》1984,21(1):265-266
A novel synthesis of perazine (10-(4-methylpiperazinyl-3-propyl)phenothiazine), likely to be applicable to 10-dialkylaminopropyl phenothiazines generally, is described. 相似文献
48.
49.
David A. Owen 《Foundations of Physics》1997,27(1):57-66
We develop here the general treatment of the Bethe—Salpeter equation for the bound state of two spin-l particles interacting through an electromagnetic interaction. The treatment here, which can be generalized to strong interactions,
combines the two-component approach utilized previously by the author in conjunction with spontaneous symmetry breaking. This
is done by using a Lagrangian having SU(2)×U(1) symmetry (without fermions) and then choosing the ′t Hooft gauge. In this way, a renormalizable theory for the interaction
of two spin-l particles via an electromagnetic interaction is ensured. 相似文献
50.
Indirect control of corporations 总被引:4,自引:0,他引:4
We consider situations in which shares ofn firms are held by the samen firms as well as by individual investors. The probelm is to determine the actual control of the firms by the individual investors.In part 1, we develop the mathematical model, and explain the basic notions of clutter and of effective reduction. In part 2 we introduce the idea of a consistent reduction, prove existence of such, and show the relation between consistent and effective reductions. In part 3 we introduce multilinear extensions and show how these can be used to calculate the effective and consistent reductions. Several examples are worked out in detail. 相似文献