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Background
Numerous stroke studies have controversially shown estrogens to be either neuroprotective or neurodamaging. The discordant results observed in rat brain ischemia models may be a consequence of discrepancies in estrogen administration modes resulting in plasma concentration profiles far from those intended. To test this hypothesis we reproduced in detail and extended an earlier study from our lab using a different mode of 17β-estradiol administration; home-made silastic capsules instead of commercial slow-release 17β-estradiol pellets. Four groups of female rats (n = 12) were ovariectomized and administered 17β-estradiol or placebo via silastic capsules. All animals underwent MCAo fourteen days after ovariectomy and were sacrificed three days later. 相似文献85.
86.
Annette Huber 《Archiv der Mathematik》2010,95(6):509-517
We establish Poincaré duality for continuous group cohomology of p-adic Lie groups with rational coefficients and compare integral structures under this duality. 相似文献
87.
Annette Pilkington 《代数通讯》2013,41(5):1965-1993
A complete lattice structure is defined on the underlying set of the orthogonal group of a real Euclidean space, by a construction analogous to that of the weak order of Coxeter systems in terms of root systems. This produces a complete rootoid in the sense of Dyer, with the orthogonal group as underlying group. It is shown that this complete lattice has a saturation property which is used along with other properties of the lattice to characterize the maximal totally ordered subsets of the lattice as collections of initial sections with respect to a total ordering on the positive roots. 相似文献
88.
Zurab Guguchia Hugo Keller Annette Bussmann-Holder Jürgen Köhler Reinhard K. Kremer 《The European Physical Journal B - Condensed Matter and Complex Systems》2013,86(10):1-4
Specific heat and magnetization measurements demonstrate that the antiferromagnetic (AFM) phase transition at T N = 5.7 K of EuTiO3 is rapidly suppressed with Sr doping in Eu x Sr1?x TiO3. Close to x = 0.25, T N = 0 K and AFM order vanishes. Above this critical concentration a finite transition temperature to an AFM phase is observed. The exchange couplings are derived as a function of x and the corresponding low temperature phase diagram is presented. 相似文献
89.
Annette Pilkington 《代数通讯》2013,41(9):3183-3202
This article investigates several convex closure operators on a finite root system. It is shown that a natural closure operator on the positive root system of a finite Weyl group satisfies the anti-exchange condition for all root systems except type F 4. 相似文献
90.
Xing Huang Detre Teschner Maria Dimitrakopoulou Alexey Fedorov Benjamin Frank Ralph Kraehnert Frank Rosowski Harry Kaiser Stephan Schunk Christiane Kuretschka Robert Schlgl Marc‐Georg Willinger Annette Trunschke 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(26):8801-8805
The direct conversion of syngas to ethanol, typically using promoted Rh catalysts, is a cornerstone reaction in CO2 utilization and hydrogen storage technologies. A rational catalyst development requires a detailed structural understanding of the activated catalyst and the role of promoters in driving chemoselectivity. Herein, we report a comprehensive atomic‐scale study of metal–promoter interactions in silica‐supported Rh, Rh–Mn, and Rh–Mn–Fe catalysts by aberration‐corrected (AC) TEM. While the catalytic reaction leads to the formation of a Rh carbide phase in the Rh–Mn/SiO2 catalyst, the addition of Fe results in the formation of bimetallic Rh–Fe alloys, which further improves the selectivity and prevents the carbide formation. In all promoted catalysts, Mn is present as an oxide decorating the metal particles. Based on the atomic insight obtained, structural and electronic modifications induced by promoters are revealed and a basis for refined theoretical models is provided. 相似文献