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Search Results: 1 - 10 of 401374 matches for " M. Schirmer "
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Editorial: 60 Jahre sterreichische Gesellschaft für Rheumatologie
Schirmer M,Leeb B
Journal für Mineralstoffwechsel , 2009,
Abstract:
Spondyloarthritis oder Morbus Bechterew: Neue Klassifikation der axialen Spondyloarthritis mit Morbus Bechterew als Endstadium
Schirmer M,Gander A
Journal für Mineralstoffwechsel , 2011,
Abstract: Mit einer Pr valenz von 0,6 1,9 % ist die axiale Spondyloarthritis (SpA) der Sammelbegriff für eine Gruppe von entzündlichen rheumatischen Krankheiten, die vor allem das axiale Skelett und die Insertionsstellen der Sehnen am Knochen (Enthesen) betreffen. Je nach Subtyp der SpA besteht eine unterschiedlich starke Assoziation mit dem MHC-I-Antigen HLA-B27. Entsprechend der Assessment of Spondyloarthritis International Society (ASAS) wird die SpA anhand der pr dominant betroffenen Region in die periphere und die axiale Form unterteilt. Die aktuelle Klassifikation der axialen SpA erfolgt mittels der 2009 ver ffentlichten ASAS-Kriterien. Bei Sakroiliitis in der Bildgebung müssen ≥ 1 SpAParameter, bei positivem HLA-B27-Befund ≥ 2 andere SpA-Parameter für die Klassifikation als SpA vorhanden sein. SpA-Parameter sind entzündlicher Rückenschmerz, Arthritis, Familienanamnese, Uveitis anterior, entzündliche Darmerkrankung, Psoriasis, Daktylitis, Enthesitis, gutes Ansprechen auf NSAR und HLA-B27-Positivit t. Die Sensitivit t dieser Kriterien liegt bei 82,9 %, die Spezifit t bei 84,4 %. Für die axiale Beteiligung der Psoriasis arthropathica werden auch die hnlichen CASPAR-Kriterien verwendet. Für die Klassifikation des Morbus Bechterew werden die 1984 modifizierten New York-Kriterien verwendet, bei denen neben spezifischen klinischen Kriterien radiologisch eine Sacroiliitis Grad 2 oder mehr bilateral oder Grad 3 4 unilateral vorhanden sein muss. Bei schwerem Verlauf kann prinzipiell jede Form der SpA mit einer axialen Beteiligung in einen Morbus Bechterew übergehen. Somit ist der Morbus Bechterew sowohl ein Subtyp der SpA, als auch eine m gliche Sp tform anderer Subtypen. Zur Verlaufs- bzw. Therapiekontrolle werden sowohl bei axialer SpA als auch bei Morbus Bechterew spezifische Scores verwendet, um Krankheitsaktivit t und Funktionsver nderungen zu dokumentieren (BASFI, BASDAI, ASDAS).
Biologika in der Rheumatologie
Herold M,B?ser M,Schirmer M
Journal für Mineralstoffwechsel , 2004,
Abstract: Biologika ist der Sammelbegriff für Medikamente, die gezielt gegen Moleküle gerichtet sind, denen krankheitsmodulierende Bedeutung zukommt. In sterreich sind derzeit 4 Biologika zugelassen, die gegen proinflammatorische Zytokine gerichtet sind. 3 Medikamente (Infliximab, Adalimumab, Etanercept) wirken gegen TNF-alpha, 1 Substanz (Anakinra) antagonisiert IL-1. Alle Biologika sind entweder als Monotherapie (Etanercept, Humira) oder in Kombination mit anderen Basistherapeutika zur Behandlung der chronischen Polyarthritis zugelassen. Ihre klinische Effizienz ist vergleichbar. Für alle Substanzen konnte eine signifikante Reduktion der radiologisch erkennbaren Progression gezeigt werden.
Investigating riparian groundwater flow close to a losing river using diurnal temperature oscillations at high vertical resolution
T. Vogt, M. Schirmer,O. A. Cirpka
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2012,
Abstract: River-water infiltration is of high relevance for hyporheic and riparian groundwater ecology as well as for drinking water supply by river-bank filtration. Heat has become a popular natural tracer to estimate exchange rates between rivers and groundwater. However, quantifying flow patterns and velocities is impeded by spatial and temporal variations of exchange fluxes, insufficient sensors spacing during field investigations, or simplifying assumptions for analysis or modeling such as uniform flow. The objective of this study is to investigate lateral shallow groundwater flow upon river-water infiltration at the shoreline of the riverbed and in the adjacent riparian zone of the River Thur in northeast Switzerland. Here we have applied distributed temperature sensing (DTS) along optical fibers wrapped around tubes to measure high-resolution vertical temperature profiles of the unsaturated zone and shallow riparian groundwater. Diurnal temperature oscillations were tracked in the subsurface and analyzed by means of dynamic harmonic regression to extract amplitudes and phase angles. Subsequent calculations of amplitude attenuation and time shift relative to the river signal show in detail vertical and temporal variations of heat transport in shallow riparian groundwater. In addition, we apply a numerical two-dimensional heat transport model for the unsaturated zone and shallow groundwater to obtain a better understanding of the observed heat transport processes in shallow riparian groundwater and to estimate the groundwater flow velocity. Our results show that the observed riparian groundwater temperature distribution cannot be described by uniform flow, but rather by horizontal groundwater flow velocities varying over depth. In addition, heat transfer of diurnal temperature oscillations from the losing river through shallow groundwater is influenced by thermal exchange with the unsaturated zone. Neglecting the influence of the unsaturated zone would cause biased interpretation and underestimation of groundwater flow velocities. The combination of high resolution field data and modeling shows the complex hydraulic and thermal processes occurring in shallow riparian groundwater close to losing river sections as well as potential errors sources for interpreting diurnal temperature oscillations in such environments.
Measuring methods for groundwater – surface water interactions: a review
E. Kalbus, F. Reinstorf,M. Schirmer
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2006,
Abstract: Interactions between groundwater and surface water play a fundamental role in the functioning of riparian ecosystems. In the context of sustainable river basin management it is crucial to understand and quantify exchange processes between groundwater and surface water. Numerous well-known methods exist for parameter estimation and process identification in aquifers and surface waters. Only in recent years has the transition zone become a subject of major research interest; thus, the need has evolved for appropriate methods applicable in this zone. This article provides an overview of the methods that are currently applied and described in the literature for estimating fluxes at the groundwater – surface water interface. Considerations for choosing appropriate methods are given including spatial and temporal scales, uncertainties, and limitations in application. It is concluded that a multi-scale approach combining multiple measuring methods may considerably constrain estimates of fluxes between groundwater and surface water.
Heat transport of diurnal temperature oscillations upon river-water infiltration investigated by fiber-optic high-resolution temperature profiling
T. Vogt,M. Schirmer,O. A. Cirpka
Hydrology and Earth System Sciences Discussions , 2011, DOI: 10.5194/hessd-8-6257-2011
Abstract: River-water infiltration is of high relevance for hyporheic and riparian groundwater ecology as well as for drinking water supply by river-bank filtration. Heat has become a popular natural tracer to estimate exchange rates between rivers and groundwater. However, quantifying flow patterns and velocities is impeded by spatial and temporal variations of exchange fluxes, insufficient sensors spacing during field investigations, or simplifying assumptions for analysis or modeling such as uniform flow. The objective of this study is to investigate local heat transport upon river-water infiltration in the riverbed and the adjacent riparian zone of the losing River Thur in northeast Switzerland. Here we have applied distributed temperature sensing (DTS) along optical fibers wrapped around three tubes to measure high-resolution temperature profiles of the unsaturated zone and shallow groundwater. Diurnal temperature oscillations were tracked in the subsurface and analyzed by means of dynamic harmonic regression to extract amplitudes and phase angles. Subsequent calculations of amplitude attenuation and time shift relative to the river signal show in detail vertical and temporal variations of heat transport. In addition, we apply a numerical two-dimensional heat transport model for the unsaturated zone and shallow groundwater to get a better understanding of the observed heat transport processes in the riparian zone. Our results show that heat transfer of diurnal temperature oscillations from the losing river through groundwater is influenced by thermal exchange with the unsaturated zone. Neglecting the influence of the unsaturated zone would cause biased interpretation and underestimation of groundwater flow velocities. In addition, the observed riparian groundwater temperature distribution cannot be described by uniform flow, but rather by horizontal groundwater flow velocities varying over depth.
Measuring methods for groundwater, surface water and their interactions: a review
E. Kalbus,F. Reinstorf,M. Schirmer
Hydrology and Earth System Sciences Discussions , 2006,
Abstract: Interactions between groundwater and surface water play a critical role in the functioning of riparian ecosystems. In the context of sustainable river basin management it is crucial to understand and quantify exchange processes between groundwater and surface water. Numerous well-known methods exist for parameter estimation and process identification in aquifers and surface waters. The transition zone, however, has only in recent years become a subject of major research interest, and the need has evolved for appropriate methods applicable in this zone. This article provides an overview of the methods that are typically used in aquifers and surface waters when studying interactions and shows the possibilities of application in the transition zone. In addition, methods particularly for use in the transition zone are presented. Considerations for choosing appropriate methods are given including spatial and temporal scales, uncertainties, and limitations in application. It is concluded that a multi-scale approach combining multiple measuring methods may considerably constrain estimates of fluxes between groundwater and surface water.
Weak lensing density profiles and mass reconstructions of the galaxy clusters Abell 1351 and Abell 1995
K. Holhjem,M. Schirmer,H. Dahle
Physics , 2009, DOI: 10.1051/0004-6361/20079006
Abstract: The aim of the present work is to study the overall mass distribution of the galaxy clusters Abell 1351 and Abell 1995 using weak gravitational lensing. These clusters have got a very different mass structure and dynamical state, and are the two extremes from a larger sample of 38 X-ray luminous clusters of similar size and redshift. We measure shear values of faint background galaxies and correct for PSF anisotropies using the KSB+ method. Two-dimensional mass maps of the clusters are created using a finite-field mass reconstruction algorithm, and verified with aperture mass statistics. The masses inferred from the reconstructions are compared to those obtained from fitting spherically symmetric SIS- and NFW-models to the tangential shear profiles. We discuss the NFW concentration parameters in detail. From the mass reconstructions we infer M200-masses of 11.7 +/- 3.1 * 10^14 h_70^-1 Msun and 10.5 +/- 2.7 * 10^14 h_70^-1 Msun for Abell 1351 and Abell 1995, respectively. About 3' north-east of the main mass peak of Abell 1351 we detect a significant secondary peak in the mass reconstruction as well as by aperture mass statistics. This feature is also traced by clusters members selected by means of their V-I colour, and hence is likely a real sub-structure of Abell 1351. From our fits to the tangential shear we infer masses on the order of M200 ~ 8-9 * 10^14 h_70^-1 Msun (Abell 1351) and M200 ~ 5-6 * 10^14 h_70^-1 Msun (Abell 1995). The concentration parameters remain poorly constrained by our weak lensing analysis.
Autonomous distributed temperature sensing for long-term heated applications in remote areas
A.-M. Kurth, N. Dawes, J. Selker,M. Schirmer
Geoscientific Instrumentation, Methods and Data Systems (GI) & Discussions (GID) , 2013, DOI: 10.5194/gi-2-71-2013
Abstract: Distributed temperature sensing (DTS) is a fiber-optical method enabling simultaneous temperature measurements over long distances. Electrical resistance heating of the metallic components of the fiber-optic cable provides information on the thermal characteristics of the cable's environment, providing valuable insight into processes occurring in the surrounding medium, such as groundwater–surface water interactions, dam stability or soil moisture. Until now, heated applications required direct handling of the DTS instrument by a researcher, rendering long-term investigations in remote areas impractical due to the often difficult and time-consuming access to the field site. Remote control and automation of the DTS instrument and heating processes, however, resolve the issue with difficult access. The data can also be remotely accessed and stored on a central database. The power supply can be grid independent, although significant infrastructure investment is required here due to high power consumption during heated applications. Solar energy must be sufficient even in worst case scenarios, e.g. during long periods of intense cloud cover, to prevent system failure due to energy shortage. In combination with storage batteries and a low heating frequency, e.g. once per day or once per week (depending on the season and the solar radiation on site), issues of high power consumption may be resolved. Safety regulations dictate adequate shielding and ground-fault protection, to safeguard animals and humans from electricity and laser sources. In this paper the autonomous DTS system is presented to allow research with heated applications of DTS in remote areas for long-term investigations of temperature distributions in the environment.
Characterization of spatial heterogeneity of groundwater-stream water interactions using multiple depth streambed temperature measurements at the reach scale
C. Schmidt, M. Bayer-Raich,M. Schirmer
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2006,
Abstract: Streambed temperatures can be easily, accurately and inexpensively measured at many locations. To characterize patterns of groundwater-stream water interaction with a high spatial resolution, we measured 140 vertical streambed temperature profiles along a 220 m section of a small man-made stream. Groundwater temperature at a sufficient depth remains nearly constant while stream water temperatures vary seasonally and diurnally. In summer, streambed temperatures of groundwater discharge zones are relatively colder than downwelling zones of stream water. Assuming vertical flow in the streambed, the observed temperatures are correlated to the magnitude of water fluxes. The water fluxes are then estimated by applying a simple analytical solution of the heat conduction-advection equation to the observed vertical temperature profiles. The calculated water fluxes through the streambed ranged between 455 Lm 2 d 1 of groundwater discharging to the stream and approximately 10 Lm 2 d 1 of stream water entering the streambed. The investigated reach was dominated by groundwater discharge with two distinct high discharge locations accounting for 50% of the total flux on 20% of the reach length.
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