oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 64 )

2018 ( 141 )

2017 ( 125 )

2016 ( 156 )

Custom range...

Search Results: 1 - 10 of 84456 matches for " W. Hampel "
All listed articles are free for downloading (OA Articles)
Page 1 /84456
Display every page Item
Reanalysis of the GALLEX solar neutrino flux and source experiments
F. Kaether,W. Hampel,G. Heusser,J. Kiko,T. Kirsten
Physics , 2010, DOI: 10.1016/j.physletb.2010.01.030
Abstract: After the completion of the gallium solar neutrino experiments at the Laboratori Nazionali del Gran Sasso (GALLEX}: 1991-1997; GNO: 1998-2003) we have retrospectively updated the GALLEX results with the help of new technical data that were impossible to acquire for principle reasons before the completion of the low rate measurement phase (that is, before the end of the GNO solar runs). Subsequent high rate experiments have allowed the calibration of absolute internal counter efficiencies and of an advanced pulse shape analysis for counter background discrimination. The updated overall result for GALLEX (only) is (73.4 +7.1 -7.3) SNU. This is 5.3% below the old value of (77.5 + 7.5 -7.8) SNU (PLB 447 (1999) 127-133) with a substantially reduced error. A similar reduction is obtained from the reanalysis of the 51Cr neutrino source experiments of 1994/1995.
Anticholinerge Therapie der OAB
Hampel C
Journal für Urologie und Urogyn?kologie , 2007,
Abstract: Kenntnisse über Differentialdiagnostik und Pathophysiologie des Blasenüberaktivit ts-Syndroms sind essentiell für eine erfolgreiche Therapie. Obwohl Verhaltenstraining und Elektrostimulation ihre Wirksamkeit bei OAB bewiesen haben, ist die Therapie der ersten Wahl nach wie vor die anticholinerge Behandlung. Dessen ungeachtet ist die Einnahmetreue der Patienten unbefriedigend, was in der letzten Zeit zu verschiedenen Medikamentenneuentwicklungen mit verbesserter Vertr glichkeit bei gleichbleibend hoher Effektivit t geführt hat. Retard-Formulierungen, extraenterale Applikationswege und Rezeptor-Subselektivit t sind hierbei die Prinzipien, welche die Behandlungsakzeptanz und Patientenzufriedenheit steigern sollen.
Discussion of "Breakdown and groups" by P. L. Davies and U. Gather
Frank Hampel
Mathematics , 2005, DOI: 10.1214/009053604000001138
Abstract: Discussion of ``Breakdown and groups'' by P. L. Davies and U. Gather [math.ST/0508497]
Adhesion of renal carcinoma cells to endothelial cells depends on PKCμ
Walburgis Brenner, Silke Beitz, Elke Schneider, Frank Benzing, Ronald E Unger, Frederik C Roos, Joachim W Thüroff, Christian Hampel
BMC Cancer , 2010, DOI: 10.1186/1471-2407-10-183
Abstract: The experiments were performed in the RCC cell lines CCF-RC1 and CCF-RC2 after pre-incubation (16 h) with the PKC inhibitors GF109203X (inhibits PKCα, βI, βII, γ, δ and ε), G?6976 (inhibits PKCα, βI and μ), RO31-8220 (inhibits PKCα, βI, βII, γ and ε) and rottlerin (inhibits PKCδ). Cell adhesion was assessed through adherence of RCC cells to an endothelial monolayer. Cell proliferation was analyzed by a BrdU incorporation assay. The expression of β1 integrins was analyzed by flow cytometry.In CCF-RC1 cells, cell adhesion was significantly reduced by G?6976 to 55% and by RO31-8220 to 45% of control. In CCF-RC2 cells, only G?6976 induced a significant reduction of cell adhesion to 50% of control levels. Proliferation of both cell lines was reduced by rottlerin to 39% and 45% of control, respectively. The β1 integrin expression on the cell surface of CCF-RC1 and CCR-RC2 cells was decreased by RO31-8220 to 8% and 7% of control, respectively. β2 and β3 integrins were undetectable in both cell lines.The combination of the PKC inhibitors leads to the assumption that PKCμ influences cell adhesion in CCF-RC1 and CCF-RC2 cells, whereas in CCF-RC1 cells PKCε also seems to be involved in this process. The expression of β1 integrins appears to be regulated in particular by PKCε. Cell proliferation was inhibited by rottlerin, so that PKCδ might be involved in cell proliferation in these cells.Formation of metastases includes the separation of single cells from the primary tumor, migration into the extracellular matrix, blood vessel invasion, adhesion to endothelium, migration through the endothelium and growth in a secondary organ [1]. During extravasation into the secondary organ, tumor cells seem to undergo the same mechanisms as leukocytes in inflammatory processes. After a loose contact to endothelial cells, integrins on the cell surface of leukocytes become activated by a chemokine induced inside-out signaling sought by endothelial cells [2] or by direct cell-cell contact [3]
V2:Performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz
J. Karch,Yu. Sobolev,M. Beck,K. Eberhardt,G. Hampel,W. Heil,R. Kieser,T. Reich,N. Trautmann,M. Ziegner
Physics , 2013, DOI: 10.1140/epja/i2014-14078-9
Abstract: The performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz with a maximum peak energy of 10 MJ is described. The solid deuterium converter with a volume of V=160 cm3 (8 mol), which is exposed to a thermal neutron fluence of 4.5x10^13 n/cm2, delivers up to 550 000 UCN per pulse outside of the biological shield at the experimental area. UCN densities of ~ 10/cm3 are obtained in stainless steel bottles of V ~ 10 L resulting in a storage efficiency of ~20%. The measured UCN yields compare well with the predictions from a Monte Carlo simulation developed to model the source and to optimize its performance for the upcoming upgrade of the TRIGA Mainz into a user facility for UCN physics.
Effect of glacial-interglacial sea-level changes on the displacement and stress field in the forearc and along the plate interface of subduction zones
T. Li ,A. Hampel
Solid Earth (SE) & Discussions (SED) , 2012, DOI: 10.5194/se-3-63-2012
Abstract: Combined seismological, space-geodetic and numerical studies have shown that the seismicity at subduction zones may be modulated by tides and glacier fluctuations on timescales of 1–100 a, because these changes in loads on Earth's surface are able to alter the stress field in the upper plate and along the plate interface. Here we use a two-dimensional finite-element model of a subduction zone to investigate how glacial-interglacial sea-level changes affect the forearc region and the plate interface. The model results show that a sea-level fall by 125 m over 100 ka causes up to 0.7 m of vertical displacement, with the maximum uplift occurring between the trench and the coast. The uplift signal induced by the sea-level fall decreases to zero ~20 km landward of the coastline. A subsequent sea-level rise by 125 m over 20 ka causes subsidence, which is again most pronounced in the submarine part of the forearc. The sea-level changes cause horizontal displacements of up to 0.12 m, which are directed seaward during sea-level fall and landward during sea-level rise. With respect to the stress field, the sea-level changes lead to variations in the vertical stress and the shear stress of up to 1.23 MPa and 0.4 MPa, respectively. The shear stress variations are highest beneath the coast, i.e. in the area where the sea-level changes cause the strongest flexure. The resulting Coulomb stress changes on the plate interface are of the order of 0.2–0.5 MPa and indicate that earthquakes are promoted during sea-level fall and delayed during sea-level rise. Our findings imply that eustatic sea-level changes during glacial-interglacial periods may have induced displacements and stress changes that were large enough to affect the seismic cycle of subduction thrusts.
Effect of glacial-interglacial sea-level changes on the displacement and stress field in the forearc and along the plate interface of subduction zones
T. Li,A. Hampel
Solid Earth Discussions , 2011, DOI: 10.5194/sed-3-1001-2011
Abstract: Combined seismological, space-geodetic and numerical studies have shown that the seismicity at subduction zones may be modulated by tides and glacier fluctuations on timescales of 1–100 a, because these changes in loads on Earth's surface are able to alter the stress field in the upper plate and along the plate interface. Here we use a two-dimensional finite-element model of a subduction zone to investigate how glacial-interglacial sea-level changes affect the forearc region and the plate interface. The model results show that a sea-level fall by 125 m over 100 ka causes up to 0.7 m of vertical displacement, with the maximum uplift occurring between the trench and the coast. The uplift signal induced by the sea-level fall decreases to zero ~20 km landward of the coastline. A subsequent sea-level rise by 125 m over 20 ka causes subsidence, which is again most pronounced in the submarine part of the forearc. The sea-level changes cause horizontal displacements of up to 0.12 m, which are directed seaward during sea-level fall and landward during sea-level rise. With respect to the stress field, the sea-level changes lead to variations in the vertical stress and the shear stress of up to 1.23 MPa and 0.4 MPa, respectively. The shear stress variations are highest beneath the coast, i.e. in the area where the sea-level changes cause the strongest flexure. The resulting Coulomb stress changes on the plate interface are of the order of 0.2–0.5 MPa and indicate that earthquakes are promoted during sea-level fall and delayed during sea-level rise. Our findings imply that eustatic sea-level changes during glacial-interglacial periods may have induced displacements and stress changes that were large enough to affect the seismic cycle of subduction thrusts.
Towards an Effective Use of Audio Conferencing in Distance Language Courses
Regine Hampel,Mirjam Hauck
Language Learning and Technology , 2004,
Abstract: In order to respond to learners' need for more flexible speaking opportunities and to overcome the geographical challenge of students spread over the United Kingdom and continental Western Europe, the Open University recently introduced Internet-based, real-time audio conferencing, thus making a groundbreaking move in the distance learning and teaching of languages. Since February 2002, online tutorials for language courses have been offered using Lyceum, an Internet-based audio-graphics conferencing tool developed in house. Our research is based on the first Open University course ever to deliver tutorials solely online, a level 2 German course, and this article considers some of the challenges of implementing online tuition. As a starting point, we present the pedagogical rationale underpinning the virtual learning and teaching environment. Then we examine the process of development and implementation of online tuition in terms of activity design, tutor training, and student support. A number of methodological tools such as logbooks, questionnaires, and observations were used to gather data. The findings of this paper highlight the complexity of the organisational as well as the pedagogical framework that contributes to the effective use of online tuition via audio conferencing systems in a distance education setting.
Investigating Language Learning Activity Using a CALL Task in the Self-access Centre
Carlos Montoro,Regine Hampel
Studies in Self-Access Learning Journal , 2011,
Abstract: This article describes a small study of the language learning activity of individual learners using a CALL task in a self-access environment. The research focuses on the nature of the language learning activity, the most salient elements that make up its structure and major disturbances observed between and within some of those elements. It is set in the context of computer-assisted language learning (CALL) and activity theory. A CALL task designed by the authors was made available online to be used as a research and learning tool. Empirical data was collected from two participants using ethnographic tools, such as participant observation and stimulated recall sessions. The analysis focuses on disturbances mainly involving the subject (i.e., the learner), mediating artefacts (e.g., the CALL task), the community (e.g., management and other self-access centre users) and the object of the activity (i.e., learning English). It is recommended that future studies should look deeper into contradictions in the learning activity from a cultural-historical perspective.
Információforrások használatának gyakorisága és információs rendszerek az élelmiszeripari társas vállalkozásban – felmérés a Dél-Alf ld régió élelmiszeripari társas vállalkozásainak vezet i k rében
Gy?rgy Hampel
Agrárinformatika Folyóirat , 2010,
Abstract: My research conducted in Hungary’s Southern Great Plain Region was aimed at the information source used for decision making by the executives of food industry enterprises and at the main characteristics and capabilities of the information systems ofthe firms. The data necessary for the research was gathered mostly with questionnaires and with interviews in the case of some bigger enterprises. Based on the results of the surveying, the executives rely consistently on the data and information from the differentmodules of their internal reporting systems. When making decisions, they also build upon information from other people (managers, employees, owners, suppliers, customers) to the same extent. The media is also a frequently used information source. The mostimportant source of information is directly linked to the information system modules closely related to production of the enterprise. The use of information systems to support decision making or forecasting is not typical in a food industry firm.
Page 1 /84456
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.