Katholieke Universiteit Leuven

About: Katholieke Universiteit Leuven is a education organization based out in Leuven, Belgium. It is known for research contribution in the topics: Population & Context (language use). The organization has 61109 authors who have published 176584 publications receiving 6210872 citations.

The safety of vedolizumab for ulcerative colitis and Crohn's disease

Abstract: Objective Vedolizumab is a gut-selective antibody to α 4 β 7 integrin for the treatment of ulcerative colitis (UC) and Crohn9s disease (CD). We report an integrated summary of the safety of vedolizumab. Design Safety data (May 2009–June 2013) from six trials of vedolizumab were integrated. Adverse events were evaluated in patients who received ≥1 dose of vedolizumab or placebo and were reported as exposure-adjusted incidence rates as the number of patients experiencing the event per 100 person-years (PYs) of exposure. Predictors of serious infection were assessed using a Cox proportional hazards model. Results In total, 2830 patients had 4811 PYs of vedolizumab exposure (median exposure range, 1–1977 days). No increased risk of any infection or serious infection was associated with vedolizumab exposure. Serious clostridial infections, sepsis and tuberculosis were reported infrequently (≤0.6% of patients). No cases of progressive multifocal leucoencephalopathy were observed. Independent risk factors for serious infection in UC were prior failure of a tumour necrosis factor α antagonist (HR, 1.99; 95% CIs 1.16 to 3.42; p=0.0122) and narcotic analgesic use (HR, 2.68; 95% CI 1.57 to 4.58; p=0.0003), and in CD were younger age (HR, 0.97; 95% CI 0.95 to 0.98; p Conclusions Vedolizumab has a favourable safety profile with low incidence rates of serious infections, infusion-related reactions and malignancies over an extended treatment period. Trial registration number NCT01177228, NCT00619489, NCT00783718, NCT00783692, NCT01224171, NCT00790933.

Virtual synchronous generators

Abstract: In electricity grids the frequency of the voltage is stabilized by a combination of the rotational inertia (rotating mass) of synchronous power generators in the grid and a control algorithm acting on the rotational speed of a number of major synchronous power generators When in future small non-synchronous generation units replace a significant part of the synchronous power generation capacity, the total rotational inertia of the synchronous generators is decreased significantly This causes large frequency variations that can end up in an unstable grid A way to stabilize the grid frequency is to add virtual rotational inertia to the distributed generators A virtual inertia can be attained for any generator by adding a short-term energy storage to it, combined with a suitable control mechanism for its power electronics converter In this way a generator can behave like a ldquoVirtual Synchronous Generatorrdquo (VSG) during short time intervals, and contribute to stabilization of the grid frequency

New insights in the relation between electron trap generation and the statistical properties of oxide breakdown

Abstract: In this paper it is demonstrated in a wide stress field range that breakdown in thin oxide layers occurs as soon as a critical density of neutral electron traps in the oxide is reached. It is proven that this corresponds to a critical hole fluence, since a unique relationship between electron trap generation and hole fluence is found independent of stress field and oxide thickness. In this way literature models relating breakdown to hole fluence or to trap generation are linked. A new model for intrinsic breakdown, based on a percolation concept, is proposed. It is shown that this model can explain the experimentally observed statistical features of the breakdown distribution, such as the increasing spread of the Q/sub BD/-distribution for ultrathin oxides. An important consequence of this large spread is the strong area dependence of the Q/sub BD/ for ultrathin oxides.

Boogie: a modular reusable verifier for object-oriented programs

Abstract: A program verifier is a complex system that uses compiler technology, program semantics, property inference, verification-condition generation, automatic decision procedures, and a user interface. This paper describes the architecture of a state-of-the-art program verifier for object-oriented programs.