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A glance at three-dimensional Alexandrov spaces

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Frontiers of Mathematics in China 2016年第5期11卷 1189-1206页

作者： Fernando GALAZ-GARCIA Institut fur Algebra und Geometrie Karlsruher Institut fiir Technologie (KIT) Karlsruhe Germany

We discuss the topology and geometry of closed Alexandrov spaces of dimension three.

关键词： Alexandrov space group action 3-manifold

Combination of "low-dose" ribavirin and interferon alfa-2a therapy followed by interferon alfa-2a monotherapy in chronic HCV-infected nonresponders and relapsers after interferon alfa-2a monotherapy

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World Journal of Gastroenterology 2001年第2期7卷 222-227页

作者： Perdita Wietzke-Braun Volker Meier Felix Braun Giuliano Ramadori Abteilung für Gastroenterologie und Endokrinologie Georg-August-UniversitatGottingenGermany

AIM To report on the efficacy, safety and tolerability of interferon alfa-2a combined with a "low dose" of ribavirin for relapsers and non responders to alpha interferon *** Thirty-four chronic hepatitis C virus-infected non-responders to interferon alfa2a monotherapy (a course of at least 3 months treatment) and 13 relapsers to interferon alfa 2a monotherapy (a dose of 3 to 6 million units three times per week for at least 20 weeks but not more than 18 months) were treated with the same dose of interferon alfa-2a used before (3 to 6 million units three times per week) and ribavirin (10 mg/ kg daily) for 6 months. In complete responders, interferon alfa-2a was administered for further 6 months at the same dose used before as *** Seven (20.6%) of 34 non-responders stopped the combined therapy due to adverse events, including two patients with histological and clinical Child A cirrhosis. In 17/27 (63%)non-responders, the combined therapy was stopped after three months because of non-response. Ten of the 27 non-responders completed the 1;2-month treatment course. At a mean follow up of 28 months (16- 37 months)after the treatment, 4/10 (15%) previous non-responders still remained complete responders,All 13 previous relapsers completed the 12-month treatment course. At a mean follow up of 22months (9 - 36 months) after treatment, 6/13(46%) the previous relapsers were stillsustained complete *** Our treatment schedule of the combined therapy for 6 months of interferon alfa2a with a low dose of ribavirin (10 mg/kg/day)followed by 6 months of interferon alfa-2amonotherapy is able to induce a sustainedcomplete response rate in 15% of non-responders and 46% of relapsers with chronic hepatitis C virus-related liver diseases comparable to those obtained with the standarddoses of ribavirin 1000 - 1200 mg/*** prospective controlled trials using lower total amounts of ribavirin in combination with interferon should be p

关键词： hepatitis C, chronic/drug therapy interferon alpha-2a/therapeutic use interferon alpha-2a/administration & dosage ribavirin/administration & dosage ribavirin/therapeutic use

VARIATIONAL DISCRETIZATION OF A CONTROL-CONSTRAINED PARABOLIC BANG-BANG OPTIMAL CONTROL PROBLEM

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Journal of Computational Mathematics 2020年第1期38卷 14-40页

作者： Nikolaus von Daniels Michael Hinze Schwerpunkt Optimierung und Approximation Universitat HamburgBundesstrase 5520146 HamburgGermany

We consider a control-constrained parabolic optimal control problem without Tikhonov term in the tracking *** the numerical treatment,we use variational discretization of its Tikhonov regularization:For the state and the adjoint equation,we apply Petrov-Galerkin schemes in time and usual conforming finite elements in *** prove a-priori estimates for the error between the discretized regularized problem and the limit *** these estimates are not robust if the regularization parameter tends to zero,we establish robust estimates,which--depending on the problem's regularity——enhance the previous *** the special case of bang-bang solutions,these estimates are further improved.A numerical example confirms our analytical findings.

关键词： Optimal control Heat equation Control constraints Finite elements A-priori error estimates Bang-bang controls

Biomechanische Untersuchungsergebnisse ber die verbesserte Verankerung von Pedikelschraubenmit resorbierbarem Zement in menschenlichen Wirbelk rpern

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2001年第1期21卷 48-51页

作者：邵景范罗永湘 Luo Yongxiang Lutz Claes Lothar Kinzl Abteilung für Chirurgie Tongji KlinikTongji medizinisches institutHuazhong Universitat für Wissenschaft und Technik Abteilung für Unfallchirurgie Hand-und Wiederherstellungschirurgie der Universitat UlmDeutschland Abteilung für Unfallchirurgische Forschung und Biomechanik der universitat Ulm Deutschland

Die Prim rstabilit t von Pedikelschrauben im Knochen h ngt in hohem Masse von der Knochendichte ab. Die Augmentation mit Zement ist ein klinisch einsetzbares Verfahren, um die Schrauben Verankerung im osteoporotischen Knochen zu *** dieser Studie wurde eine neuartiges resorbierbares Knochenersatzmaterial (α BSM TM ) für diese Augmentation benutzt. Biomechanische Testungen wurden in vitro bei 16 Lendwirbelk rpern (L3-L5) aus 6 Individuen(75,2±13,7 Jahre) durchgeführt. Vor der biomechanischen Testung wurde bei allen Pr paraten die trabekul re Knochendichte mittels pQCT gemessen und beide Pedikel mit USS Pedikelschrauben (5,0 mm × 45 mm) besetzt, von welchen eine mit α BSM TM augmentiert war. Beim axialen Auszugstest wurden die maximale axiale Auszugskraft (F max) sowie die Energieaufnahme bestimmt. Der Medianwert der F max stieg beim Auszugstest durch die Zementierung mit α BSM TM um 80 % von 370 N (ohne Zement) auf 665 N (mit Zement). Die Energieaufnahme bis zum Erreichen der F max (E F max) und bei Dislokation bis 2,0 mm (E 2 mm) steigerte sich ebenfalls um 83 % und 68 %. Die Unterschiede waren signifikant. (Wilcoxon′s Test, P und r =0,9585). Unsere Resultate zeigen, da eine Augmentation mit dem α BSM TM die primare Stabilitat von Pedikelschrauben verbessern kann. Der Effekt scheint auf einer Optimierung der Kontaktfl che und einer Aussteifung der schraubennahen Spongiosa zu beruhen. Das Material k nnte geeignet sein, die Verankerung von Pedikelschrauben bei osteoporotischen Patieten zu verbessern.

关键词： Biomechanik Zement Pedikelschraube Stabilit t Wirbelk rper

Real-valued valuations on Sobolev spaces

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Science China Mathematics 2016年第5期59卷 921-934页

作者： MA Dan Institut für Diskrete Mathematik und Geometrie Technische Universitat Wien Wien 1040 Austria

Continuous, SL(n) and translation invariant real-valued valuations on Sobolev spaces are *** centro-affine Hadwiger's theorem is applied. In the homogeneous case, these valuations turn out to be L^p-norms raised to p-... 详细信息

关键词： Sobolev space valuation convex polytope

F?(H2O)+CH3I Ligand Exchange Reaction Dynamics

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Chinese Journal of Chemical Physics 2020年第2期33卷 210-216,I0003,I0039-I0040页

作者： Bjorn Bastian Tim Michaelsen Milan Oncák Jennifer Meyer Roland Wester Institut für Ionenphysik und Angewandte Physik Universitat InnsbruckTechnikerstraβe 256020 InnsbruckAustria

Single hydration of the gas phase F^-+CH3I→CH3F reaction allows to probe solvent effects on a fundamental nucleophilic substitution *** the same time,the addition of a solvent molecule opens alternative product ***,we present crossed beam imaging results on the dynamics of the F^-(H2O)+CH3I→[FCH3I]^-+H2O ligand exchange pathway at collision energies between 0.3 and 2.6 *** kinetic energies are constrained by the stability requirement of the weakly bound product *** implies substantial internal excitation of the water molecule and disfavors effcient energy redistribution in an intermediate complex,which is reflected by the suppression of low kinetic energies as collision energy *** 0.3 eV,internal nucleophilic displacement is important and is discussed in light of the competing nucleophilic substitution pathways that form I^- and I^-(H2O).

关键词： Reaction dynamics Ligand exchange Microsolvation Crossed beams Velocity map imaging

A New Convergent Explicit Tree-Grid Method for HJB Equations in One Space Dimension

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Numerical Mathematics(Theory,Methods and Applications) 2018年第1期11卷 1-29页

作者： Igor Kossaczky Matthias Ehrhardt Michael Gunther Lehrstuhl fur Angewandte Mathematik und Numerische Analysis Fakultat fur Mathematik und NaturwissenschaftenBergische Universitat WuppertalGaußstrasse 2042119 WuppertalGermany

In this work we introduce a new unconditionally convergent explicit Tree-Grid Method for solving stochastic control problems with one space and one time dimension or equivalently,the corresponding Hamilton-Jacobi-Bellman *** prove the convergence of the method and outline the relationships to other numerical *** case of vanishing diffusion is treated by introducing an artificial diffusion *** illustrate the superiority of our method to the standardly used implicit finite difference method on two numerical examples from finance.

关键词： Tree-Grid Method Hamilton-Jacobi-Bellman equation Stochastic control problem

The influence of hydrochar from biogas digestate on soil improvement and plant growth aspects

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Biochar 2020年第2期2卷 177-194页

作者： Megan de Jager Michael Rohrdanz Luise Giani Carl Von Ossietzky universitat Institut für Biologie und UmweltwissenschaftenOldenburgGermany

Hydrochar(HC),produced by hydrothermal carbonization,offers technical advantages over biochar(BC)produced by pyrolysis,and is suitable for soil amelioration,carbon sequestration,and enhanced plant *** grain size has been shown to influence nutrient retention,microbial colonization and aggregate formation;however,similar research for HC is *** trials were conducted to investigate the influence of HC grain size[coarse(6.3-2 mm),medium(2-0.63 mm)and fine(50%in all *** effect on NO_(3)^(−)content was indeterminable,while there was little to no effect on biom

关键词： Hydrochar Soil improvement Grain size Plant available nutrients

Regulation of neural stem/progenitor cell functions by P2X and P2Y receptors

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Neural Regeneration Research 2017年第3期12卷 395-396页

作者： Peter Illes Patrizia Rubini Rudolf-Boehm-Institut fur Pharmakologie und Toxikologie Universitat LeipzigLeipzigGermany

Neural stem/progenitor cells：Radial glial cells constitute multipotent cells in the ventricular zone,lining the wall of the lateral ventricle of the embryonic *** have the capacity to give rise to cells belonging to ... 详细信息

关键词： NSCs cell Regulation of neural stem/progenitor cell functions by P2X and P2Y receptors stem