Institution
University of Potsdam
Education•Potsdam, Germany•
About: University of Potsdam is a education organization based out in Potsdam, Germany. It is known for research contribution in the topics: Population & Computer science. The organization has 9629 authors who have published 26740 publications receiving 759745 citations. The organization is also known as: Universität Potsdam.
Papers published on a yearly basis
Papers
More filters
•
TL;DR: This work derives two instances of the Nash logistic regression and the Nash support vector machine, and empirically explore their properties in a case study on email spam filtering.
Abstract: The standard assumption of identically distributed training and test data is violated when the test data are generated in response to the presence of a predictive model. This becomes apparent, for example, in the context of email spam filtering. Here, email service providers employ spam filters, and spam senders engineer campaign templates to achieve a high rate of successful deliveries despite the filters. We model the interaction between the learner and the data generator as a static game in which the cost functions of the learner and the data generator are not necessarily antagonistic. We identify conditions under which this prediction game has a unique Nash equilibrium and derive algorithms that find the equilibrial prediction model. We derive two instances, the Nash logistic regression and the Nash support vector machine, and empirically explore their properties in a case study on email spam filtering.
204 citations
••
TL;DR: It is argued that the chimera emerges because of effective bistability, which dynamically appears in the originally monostable system due to internal delayed feedback in individual units.
Abstract: We demonstrate the emergence of a complex state in a homogeneous ensemble of globally coupled identical oscillators, reminiscent of chimera states in nonlocally coupled oscillator lattices. In this regime some part of the ensemble forms a regularly evolving cluster, while all other units irregularly oscillate and remain asynchronous. We argue that the chimera emerges because of effective bistability, which dynamically appears in the originally monostable system due to internal delayed feedback in individual units. Additionally, we present two examples of chimeras in bistable systems with frequency-dependent phase shift in the global coupling.
204 citations
••
TL;DR: The non-ergodicity of a simple Markovian stochastic process with space-dependent diffusion coefficient D(x) is demonstrated, which yields anomalous diffusion of the form hx 2 (t)i ' t 2/(2 ) .
Abstract: We demonstrate the non-ergodicity of a simple Markovian stochastic processes with space-dependent diffusion coefficient $D(x)$. For power-law forms $D(x) \simeq|x|^{\alpha}$, this process yield anomalous diffusion of the form $\ \simeq t^{2/(2-\alpha)}$. Interestingly, in both the sub- and superdiffusive regimes we observe weak ergodicity breaking: the scaling of the time averaged mean squared displacement $\{\delta^2}$ remains \emph{linear} and thus differs from the corresponding ensemble average $\ $. We analyze the non-ergodic behavior of this process in terms of the ergodicity breaking parameters and the distribution of amplitude scatter of $\{\delta^2}$. This model represents an alternative approach to non-ergodic, anomalous diffusion that might be particularly relevant for diffusion in heterogeneous media.
204 citations
••
TL;DR: In this article, Bovine serum albumin (BSA) was modified by covalent attachment of chlorogenic acid using different concentrations at pH 9. The structural changes were studied using circular dichroism, differential scanning calorimetry (DSC), intrinsic fluorescence, and binding of anilinonaphthalenesulfonic acid.
204 citations
••
TL;DR: In this paper, the effect of multi-component cardiac rehabilitation (CR) on total mortality and other clinical endpoints after an acute coronary event was evaluated, focusing on actual clinical practice, and the aim was to evaluate the impact of CR on overall clinical performance.
Abstract: Background The prognostic effect of multi-component cardiac rehabilitation (CR) in the modern era of statins and acute revascularisation remains controversial. Focusing on actual clinical practice, the aim was to evaluate the effect of CR on total mortality and other clinical endpoints after an acute coronary event. Design Structured review and meta-analysis. Methods Randomised controlled trials (RCTs), retrospective controlled cohort studies (rCCSs) and prospective controlled cohort studies (pCCSs) evaluating patients after acute coronary syndrome (ACS), coronary artery bypass grafting (CABG) or mixed populations with coronary artery disease (CAD) were included, provided the index event was in 1995 or later. Results Out of n = 18,534 abstracts, 25 studies were identified for final evaluation (RCT: n = 1; pCCS: n = 7; rCCS: n = 17), including n = 219,702 patients (after ACS: n = 46,338; after CABG: n = 14,583; mixed populations: n = 158,781; mean follow-up: 40 months). Heterogeneity in design, biometrical assessment of results and potential confounders was evident. CCSs evaluating ACS patients showed a significantly reduced mortality for CR participants (pCCS: hazard ratio (HR) 0.37, 95% confidence interval (CI) 0.20-0.69; rCCS: HR 0.64, 95% CI 0.49-0.84; odds ratio 0.20, 95% CI 0.08-0.48), but the single RCT fulfilling Cardiac Rehabilitation Outcome Study (CROS) inclusion criteria showed neutral results. CR participation was also associated with reduced mortality after CABG (rCCS: HR 0.62, 95% CI 0.54-0.70) and in mixed CAD populations. Conclusions CR participation after ACS and CABG is associated with reduced mortality even in the modern era of CAD treatment. However, the heterogeneity of study designs and CR programmes highlights the need for defining internationally accepted standards in CR delivery and scientific evaluation.
204 citations
Authors
Showing all 9969 results
Name | H-index | Papers | Citations |
---|---|---|---|
Cyrus Cooper | 204 | 1869 | 206782 |
Markus Antonietti | 176 | 1068 | 127235 |
Marc Weber | 167 | 2716 | 153502 |
Peter Capak | 147 | 679 | 70483 |
Heiner Boeing | 140 | 1024 | 92580 |
Alisdair R. Fernie | 133 | 1010 | 64026 |
Klaus-Robert Müller | 129 | 764 | 79391 |
Claudia Felser | 113 | 1198 | 58589 |
Guochun Zhao | 113 | 406 | 40886 |
Matthias Steinmetz | 112 | 461 | 67802 |
Jürgen Kurths | 105 | 1038 | 62179 |
Peter Schmidt | 105 | 638 | 61822 |
Erwin P. Bottinger | 102 | 342 | 42089 |
Knud Jahnke | 94 | 352 | 31542 |
Gerd Gigerenzer | 94 | 533 | 52356 |