113 research outputs found
Probing new physics in electroweak penguins through B_d and B_s decays
An enhanced electroweak penguin amplitude due to the presence of unknown new
physics can explain the discrepancies found between theory and experiment in
the B -> pi K decays, in particular in A_CP(B^- -> pi^0 K^-) - A_CP(\bar{B}^0
-> pi^+ K^-), but the current precision of the theoretical and experimental
results does not allow to draw a firm conclusion. We argue that the \bar{B}_s
-> phi rho^0 and \bar{B}_s -> phi pi^0 decays offer an additional tool to
investigate this possibility. These purely isospin-violating decays are
dominated by electroweak penguins and we show that in presence of a new physics
contribution their branching ratio can be enhanced by about an order of
magnitude, without violating any constraints from other hadronic B decays. This
makes them very interesting modes for LHCb and future B factories. In
arXiv:1011.6319 we have performed both a model-independent analysis and a study
within realistic New Physics models such as a modified-Z^0-penguin scenario, a
model with an additional Z' boson and the MSSM. In this article we summarise
the most important results of our study.Comment: 8 pages, 5 figures, LaTeX. Talk given at Discrete2010, Rome, 6-11
December 2010; References adde
Phenomenological consequences of radiative flavor violation in the MSSM
In this article we investigate the consequences of radiative flavor violation
(RFV) in the Minimal Supersymmetric Standard Model (MSSM). In this framework
the small off-diagonal elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix
and the small quark masses of the first two generations are generated from the
trilinear supersymmetry-breaking terms. The impact of RFV on flavor-physics
observables is studied in detail. We focus on the limiting cases in which the
CKM matrix is either generated in the down-sector, i.e. by the soft
SUSY-breaking mass insertions delta^dLR_i3 (i=1,2), or in the up-quark sector,
i.e. by the mass insertions delta^uLR_i3. In the first case we find an
enhancement of b->s gamma, which constrains the allowed range of sparticle
masses (Fig. 3). In addition, neutral Higgs penguins significantly contribute
to B_s,d->mu^+mu^- and, if also delta^dLR_32 is different from zero, these
Higgs effects are capable of explaining the observed CP phase in the B_s
system. If, on the other hand, the CKM generation takes place in the up-sector,
|epsilon_K| receives additional positive contributions enforcing large squark
and gluino masses (see Fig. 8). In this case also the rare decay K->pi nu nu
receives sizable contributions. In conclusion we find that for SUSY masses
around 1 TeV RFV is an interesting alternative to Minimal Flavor Violation
(MFV).Comment: 12 pages, 10 figures, version accepted for publication in PRD, eq.
(14) and eq. (15) correcte
Appraisal of the Karnofsky Performance Status and proposal of a simple algorithmic system for its evaluation
BACKGROUND: For over 60Â years, the Karnofsky Performance Status (KPS) has proven itself a valuable tool with which to perform measurement of and comparison between the functional statuses of individual patients. In recent decades conditions for patients have changed, and so too has the KPS undergone several adjustments since its initial development. DISCUSSION: The most important works regarding the KPS tend to focus upon a variety of issues, including but not limited to reliability, validity and health-related quality of life. Also discussed is the question of what quantity the KPS may in fact be said to measure. The KPS is increasingly used as a prognostic factor in patient assessment. Thus, questions regarding if and how it affects survival are relevant. In this paper, we propose an algorithm which uses a minimum of two and a maximum of three questions to facilitate an adequate and efficient evaluation of the KPS. SUMMARY: This review honors the original intention of the discoverer and gives an overview of adaptations made in recent years. The proposed algorithm suggests specific updates with the goal of ensuring continued adequacy and expediency in the determination of the KPS
The freshwater balance of polar regions in transient simulations from 1500 to 2100 AD using a comprehensive coupled climate model
The ocean and sea ice in both polar regions are important reservoirs of freshwater within the climate system. While the response of these reservoirs to future climate change has been studied intensively, the sensitivity of the polar freshwater balance to natural forcing variations during preindustrial times has received less attention. Using an ensemble of transient simulations from 1500 to 2100 AD we put present-day and future states of the polar freshwater balance in the context of low frequency variability of the past five centuries. This is done by focusing on different multi-decadal periods of characteristic external forcing. In the Arctic, freshwater is shifted from the ocean to sea ice during the Maunder Minimum while the total amount of freshwater within the Arctic domain remains unchanged. In contrast, the subsequent Dalton Minimum does not leave an imprint on the slow-reacting reservoirs of the ocean and sea ice, but triggers a drop in the import of freshwater through the atmosphere. During the twentieth and twenty-first century the build-up of freshwater in the Arctic Ocean leads to a strengthening of the liquid export. The Arctic freshwater balance is shifted towards being a large source of freshwater to the North Atlantic ocean. The Antarctic freshwater cycle, on the other hand, appears to be insensitive to preindustrial variations in external forcing. In line with the rising temperature during the industrial era the freshwater budget becomes increasingly unbalanced and strengthens the high latitude's Southern Ocean as a source of liquid freshwater to lower latitude ocean
ApplikaS : Applikationenkatalog für nicht-medizinische Supportleistungen in Spitälern
Um die Komplexität der vielseitigen Daten - auch in den nicht-medizinischen Supportleistungen in Spitälern [FM in HC] - im Hinblick auf mehr Transparenz handhaben zu können, sind Spitäler auf den Einsatz von geeigneten und sinnvoll abgestimmten Softwareapplikationen angewiesen. Bisher wurde der Integration und Abstimmung der nicht-medizinischen Applikationen sowohl in der Theorie, als auch in der Praxis wenig Beachtung geschenkt. Ziel war es daher, durch Befragungen eine Übersicht über die Situation der eingesetzten Applikationen im Bereich der nicht-medizinischen Supportleistungen zu erhalten und aufgrund von Recherchen zu eruieren, welche Applikationen auf dem Markt in Bezug auf eine möglichst umfangreiche Funktionalitäten-Abdeckung für den Spitalbetrieb vorhanden und geeignet sind. Diese Grundlagen sollen einerseits die Ausgangslage beleuchten und somit FM in HC- und auch IT-Verantwortliche in der Thematik sensibilisieren und andererseits auch Anbietern den Bedarf an Abstimmung innerhalb des FM-Bereichs aufzeigen. Der Applikationenkatalog ApplikaS ist, zusammen mit dem Kennzahlenmodell KenmoS und dem Prozessmodell PromoS, Teil des Referenzmodells für nicht-medizinische Supportleistungen in Spitälern RemoS und Basis für den Leitfaden zum Einsatz von SAP für das Facility Management im Gesundheitswesen LesapS und das Assessment-, Simulations- und Benchmarking-Tool für das Facility Management im Gesundheitswesen
Improving foveal avascular zone segmentation in fluorescein angiograms by leveraging manual vessel labels from public color fundus pictures
In clinical routine, ophthalmologists frequently analyze the shape and size of the foveal avascular zone (FAZ) to detect and monitor retinal diseases. In order to extract those parameters, the contours of the FAZ need to be segmented, which is normally achieved by analyzing the retinal vasculature (RV) around the macula in fluorescein angiograms (FA). Computer-aided segmentation methods based on deep learning (DL) can automate this task. However, current approaches for segmenting the FAZ are often tailored to a specific dataset or require manual initialization. Furthermore, they do not take the variability and challenges of clinical FA into account, which are often of low quality and difficult to analyze. In this paper we propose a DL-based framework to automatically segment the FAZ in challenging FA scans from clinical routine. Our approach mimics the workflow of retinal experts by using additional RV labels as a guidance during training. Hence, our model is able to produce RV segmentations simultaneously. We minimize the annotation work by using a multi-modal approach that leverages already available public datasets of color fundus pictures (CFPs) and their respective manual RV labels. Our experimental evaluation on two datasets with FA from 1) clinical routine and 2) large multicenter clinical trials shows that the addition of weak RV labels as a guidance during training improves the FAZ segmentation significantly with respect to using only manual FAZ annotations.Fil: Hofer, Dominik. Medizinische Universität Wien; AustriaFil: Schmidt Erfurth, Ursula. Medizinische Universität Wien; AustriaFil: Orlando, JosĂ© Ignacio. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Grupo de Plasmas Densos Magnetizados. Provincia de Buenos Aires. GobernaciĂłn. Comision de Investigaciones CientĂficas. Grupo de Plasmas Densos Magnetizados; Argentina. Medizinische Universität Wien; AustriaFil: Goldbach, Felix. Medizinische Universität Wien; AustriaFil: Gerendas, Bianca S.. Medizinische Universität Wien; AustriaFil: Seeböck, Philipp. Medizinische Universität Wien; Austri
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