A Calibration System for Compton Polarimetry at e+e−e^+e^- Linear Colliders

Polarimetry with permille-level precision is essential for future electron-positron linear colliders. Compton polarimeters can reach negligible statistical uncertainties within seconds of measurement time. The dominating systematic uncertainties originate from the response and alignment of the detector which records the Compton scattered electrons. The robust baseline technology for the Compton polarimeters foreseen at future linear colliders is based on an array of gas Cherenkov detectors read out by photomultipliers. In this paper, we will present a calibration method which promises to monitor nonlinearities in the response of such a detector at the level of a few permille. This method has been implemented in an LED-based calibration system which matches the existing prototype detector. The performance of this calibration system is sufficient to control the corresponding contribution to the total uncertainty on the extracted polarisation to better than $0.1\%$.Comment: 27 pages, 17 figure

Spin Transport and Polarimetry in the Beam Delivery System of the International Linear Collider

Polarised electron and positron beams are key ingredients to the physics programme of future linear colliders. Due to the chiral nature of weak interactions in the Standard Model - and possibly beyond - the knowledge of the luminosity-weighted average beam polarisation at the $e^+e^-$ interaction point is of similar importance as the knowledge of the luminosity and has to be controlled to permille-level precision in order to fully exploit the physics potential. The current concept to reach this challenging goal combines measurements from Laser-Compton polarimeters before and after the interaction point with measurements at the interaction point. A key element for this enterprise is the understanding of spin-transport effects between the polarimeters and the interaction point as well as collision effects. We show that without collisions, the polarimeters can be cross-calibrated to 0.1 %, and we discuss in detail the impact of collision effects and beam parameters on the polarisation value relevant for the interpretation of the $e^+e^-$ collision data.Comment: 34 pages, 11 figure

A Quartz Cherenkov Detector for Compton-Polarimetry at Future e+e- Colliders

Precision polarimetry is essential for future e+ e- colliders and requires Compton polarimeters designed for negligible statistical uncertainties. In this paper, we discuss the design and construction of a quartz Cherenkov detector for such Compton polarimeters. The detector concept has been developed with regard to the main systematic uncertainties of the polarisation measurements, namely the linearity of the detector response and detector alignment. Simulation studies presented here imply that the light yield reachable by using quartz as Cherenkov medium allows to resolve in the Cherenkov photon spectra individual peaks corresponding to different numbers of Compton electrons. The benefits of the application of a detector with such single-peak resolution to the polarisation measurement are shown for the example of the upstream polarimeters foreseen at the International Linear Collider. Results of a first testbeam campaign with a four-channel prototype confirming simulation predictions for single electrons are presented

Internationales Benchmarking von Gesundheitssystemen : Ansatz zur Problemlösung?

Die Gesundheitssysteme stehen weltweit zur Diskussion. Kann internationales Benchmarking ganzer Gesundheitssysteme dazu beitragen, Lösungen für deren Probleme zu finden? Diese Arbeit stellt drei aktuelle Ansätze solcher Vergleiche vor. Hierbei werden die Erkenntnisse ebenso erläutert wie die Probleme, vor deren Hintergrund diese betrachtet werden müssen. Insgesamt stellt sich heraus, dass die beschriebenen groben Vergleiche ganzer Systeme nicht dazu geeignet erscheinen, konkrete Lösungen aufzuzeigen. Aber sie erregen weltweite Aufmerksamkeit, so dass öffentlichkeitswirksamer Druck auf die politischen Entscheidungsträger aufgebaut wird, die dadurch angehalten werden, notwendige Reformen anzustoßen.The health systems are discussed worldwide. Is international benchmarking of whole health systems a potential tool to give answers to their problems? This paper introduces three current concepts of such comparisons. Their findings are explained as well as the problems, which are the background ahead of which those results have to be contemplated. Overall there is the conclusion that the rough comparisons of whole systems as described don?t seem to be qualified to show up concrete solutions. But they create worldwide attention, so that public pressure on the political decision makers is built up, which invites these to start necessary reforms

Empirische Erfahrungen, Versichertenverhalten zu steuern

Steigende Kosten in den meisten Gesundheitssystemen und die damit verbundenen Finanzierungsprobleme stehen im Focus von vielen empirischen Untersuchungen. Wissenschaftler sind der Meinung, dass falsch gesetzte Anreize einer der Hauptgründe hierfür darstellen. Die vorliegende Arbeit umreißt die Möglichkeiten, in wie weit auf der Nachfragerseite in der Krankenversicherung durch unterschiedliche Vertragsmodelle Steuerungsmöglichkeiten vorliegen. Zu Beginn wird ein kurzer Überblick über die ökonomischen Besonderheiten im Gesundheitssektor gegeben. Daran anknüpfend werden einige bekannte Vertragsmodelle vorgestellt und hervorgehoben, welche Anreizwirkungen damit beabsichtigt sind. Darauf aufbauend werden drei empirische Untersuchungen und ihre Schlussfolgerungen vorgestellt. Im Ergebnis wird herausgestellt, dass es zu Verhaltensänderungen auf der Nachfragerseite kommt, wenn die Anreize unterschiedlich gesetzt werden. Ziel ist es, mit diesen Erkenntnissen eine höhere Effizienz im Gesundheitssektor zu ermöglichen.Increasing costs of most healthcare systems result in (major) financing problems and thus are the focus of many empirical inquiries. Researchers have found that mismanagement is often a consequence of misplaced incentives. This paper tries to outline some cases in which the demand side of healthcare changes its behaviour under different circumstances or incentives. An introduction is given as a short overview of the healthcare sector with its economical specialties. This is followed by an outline of some well established contract models and their effect on the demander?s incentives. The paper concludes with the presentation of three specific cases studied. Showing differences in the demander?s behaviour and health under the influence of differing incentives, this paper tries to point out possible targets for expense reduction and increased efficiency

Ion induced solid flow

Amorphous solids can flow over very long periods of time. Solid flow can also be artificially enhanced by creating defects, as by Ion Beam Sputtering (IBS) in which collimated ions with energies in the 0.1 to 10 keV range impact a solid target, eroding its surface and inducing formation of nanometric structures. Recent experiments have challenged knowledge accumulated during the last two decades so that a basic understanding of self-organized nano-pattern formation under IBS is still lacking. We show that considering the irradiated solid to flow like a highly viscous liquids can account for the complex IBS morphological phase diagram, relegating erosion to a subsidiary role and demonstrating a controllable instance of solid flow at the nanoscale. This new perspective can allow for a full harnessing of this bottom-up route to nanostructuring.Comment: 17 pages, 5 figure

Marshall University Music Department Presents the 2014 Birke Fine Arts Festival, Trending Now: Artists and Audiences in the Information Age, Fifth Annual Festival of New Music, Concert Five

https://mds.marshall.edu/music_perf/1293/thumbnail.jp

Efficacy and cost-effectiveness of the 13C-urea breath test as the primary diagnostic investigation for the detection of Helicobacter pylori infection compared to invasive and non-invasive diagnostic tests

Background: Helicobacter pylori (H. pylori) is one of the most common bacterial infections in humans. There is a risk factor for gastric or duodenal ulcers, gastric cancer and MALT (Mucosa Associated Lymphoid Tissue)-Lymphomas. There are several invasive and non-invasive methods available for the diagnosis of H. pylori. The 13C-urea breath test is a non-invasive method recommended for monitoring H. pylori eradication therapy. However, this test is not yet used for primary assessment of H. pylori in Germany. Objectives: What are the clinical and health economic benefits of the 13C-urea breath test in the primary assessment of H. pylori compared to other invasive and non-invasive methods? Methods: A systematic literature search including a hand search was performed for studies investigating test criteria and cost-effectiveness of the 13C-urea breath test in comparison to other methods used in the primary assessment of H. pylori. Only studies that directly compared the 13C-urea breath test to other H. pylori-tests were included. For the medical part, biopsy-based tests were used as the gold standard. Results: 30 medical studies are included. Compared to the immunoglobulin G (IgG) test, the sensitivity of the 13C-urea breath test is higher in twelve studies, lower in six studies and one study reports no differences. The specificity is higher in 13 studies, lower in three studies and two studies report no differences. Compared to the stool antigen test, the sensitivity of the 13C-urea breath test is higher in nine studies, lower in three studies and one study reports no difference. The specificity is higher in nine studies, lower in two studies and two studies report no differences. Compared to the urease test, the sensitivity of the 13C-urea breath test is higher in four studies, lower in three studies and four studies report no differences. The specificity is higher in five studies, lower in five studies and one study reports no difference. Compared to histology, the sensitivity of the 13C-urea breath test is higher in one study and lower in two studies. The specificity is higher in two studies and lower in one study. One study each compares the 13C-urea breath test to the 14C-urea breath test and the polymerase chain reaction (PCR) test, respectively, and reports no difference in sensitivity and specificity with the 14C-urea breath test, and lower sensitivity and higher specificity compared to PCR. The statistical significance of these differences is described for six of the 30 studies. Nine health economic evaluations are included in the Health Technology Assessment (HTA) report. Among these studies, the test-and-treat strategy using the 13C-urea breath test is compared to test-and-treat using serology in six analyses and to test and treat using the stool antigen test in three analyses. Thereby, test-and-treat using the breath test is shown to be cost-effective over the serology based strategy in three models and is dominated by a test-and-treat strategy using the stool antigen test in one model. A cost-effectiveness comparison between the urea breath test approach and the empirical antisecretory therapy is carried out in four studies. Of these, two studies report that the strategy using the urea breath test is cost-effective over the empirical antisecretory therapy. In two studies, test-and-treat using the 13C-urea breath test is compared to the empirical eradication therapy and in five studies to endoscopy-based strategies. The breath test approach dominates endoscopy in two studies and is dominated by this strategy in one study. Discussion: All included medical and economic studies are limited to a greater or lesser extent. Additionally, the results of the studies are heterogeneous regarding medical and economic outcomes respectively. Thus, the majority of the medical studies do not report the statistical significance of the differences in sensitivity and specificity. In direct comparisons the 13C- urea breath test shows higher sensitivity and specificity than the IgG and stool antigen tests. In comparison to the urease test, results for sensitivity are inconsistent, and the specificity is slightly higher for the 13C-urea breath test. There are not enough results for comparisons between the 13C-urea breath test and the 14C-urea breath test, histology and PCR to describe tendencies. The included economic studies suggest that the test-and-treat strategy using the 13C-urea breath test is cost-effective compared to test-and-treat using serology as well as empirical antisecretory therapies. Due to a lack of valid studies, it is not possible to assess the breath test approach in comparison to test-and-treat using the stool antigen test and the empirical eradication therapy respectively, regarding the cost-effectiveness. The results of economic analyses comparing test-and-treat using the breath test to endoscopy strategies are too heterogeneous to draw any conclusions. Overall, none of the included economic models is able to completely capture the complexity of managing patients with dyspeptic complaints. Conclusions/Recommendations: Based on available medical and economic studies, there is no sufficient evidence to recommend test and-treat using 13C-urea breath testing for the detection of H. pylori infection as the standard procedure for the management of uninvestigated dyspepsia in the German health care system. In addition, it must be considered that the DVGS guidelines of the Deutsche Gesellschaft für Verdauungs- und Stoffwechselkrankheiten (DVGS) recommend endoscopy based methods for the management of patients with dyspeptic complaints

Marshall University Music Department Presents a Concert of Soloists Competition, February 5, 2012

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Marshall University Music Department Presents a Faculty Recital, Henning Vauth, Piano

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