Evolution of marine storminess in the Belgian part of the North Sea

Severe storms have affected European coast lines in the past but knowledge on changes in storminess for the last decades is still sparse. Climate change is assumed to be a main driving factor with the potential to induce changes on the intensity, duration and frequency of powerful marine storms, including a long-term influence on peak wind speeds, surges and waves. It is, therefore, important to investigate whether in the last decades changes in the magnitude of storms, their duration and frequency could be observed. Understanding trends in storminess in the last decades will help to better prepare coastal managers for future events, taking into account potential changes on storm occurrence and magnitude to improve planning of mitigation and adaptation strategies. The purpose of this study was to focus on the evolution of extreme wind conditions, wave height and storm surge levels in the North Sea Region, especially in the Belgian part of the North Sea (BPNS). Based on the analysis performed it is concluded that no clear trend can be observed for the occurrence of significant increasing extreme wind speeds over the BPNS. Furthermore, one can conclude that not enough scientific evidence is available to support scenarios with increased wave height or storminess

Linux kernel compaction through cold code swapping

There is a growing trend to use general-purpose operating systems like Linux in embedded systems. Previous research focused on using compaction and specialization techniques to adapt a general-purpose OS to the memory-constrained environment, presented by most, embedded systems. However, there is still room for improvement: it has been shown that even after application of the aforementioned techniques more than 50% of the kernel code remains unexecuted under normal system operation. We introduce a new technique that reduces the Linux kernel code memory footprint, through on-demand code loading of infrequently executed code, for systems that support virtual memory. In this paper, we describe our general approach, and we study code placement algorithms to minimize the performance impact of the code loading. A code, size reduction of 68% is achieved, with a 2.2% execution speedup of the system-mode execution time, for a case study based on the MediaBench II benchmark suite

High resolution pulse width modulators in FPGA

Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Á. de Castro, G. Sutter, S. C. Huerta, and J. A. Cobos, "High resolution pulse width modulators in FPGA",3rd Southern Conference on Programmable Logic, SPL, 2007, Mar del Plata (Argentina), 2007, pp. 137 - 142Pulse width modulation (PWM) is a very common technique used in different applications, from the control of motors, switching power converters (power supplies), audio amplifiers or illumination systems. In some of those applications, the pulse frequency has increased so much in the last years that the resolution obtained with classical (counter) techniques is not enough. This paper explains some methods used for increasing the resolution of PWMs and proposes a new method based on the resources available in almost every FPGA nowadays

Physical Activity Status in Patients With Coronary Heart Disease: Results From the Cross-Sectional EUROASPIRE Surveys.

BACKGROUND: The study aim was to assess the physical activity levels as well as the intention to become physically active in patients with stable coronary heart disease (CHD) with a special focus on the association with their risk profile. METHODS: Analyses are based on the cross-sectional EUROASPIRE IV surveys. Information was available on 8966 patients in EUROASPIRE III and on 7998 patients in EUROASPIRE IV. Physical activity level according to patients risk profile and their medical management was assessed, the intention to become physically active was investigated and a time trend analysis was performed. RESULTS: A better cardiovascular risk profile as well as receiving physical activity advice or weight loss advice was associated with better physical activity levels. The physical activity status improved significantly over time, the proportion of patients reporting vigorous physical activity for at least 20 minutes ≥ 3 times/week increased from 14.1% to 20.2% (P < .001). Similarly, a significantly greater proportion of patients are in the maintenance stage (36.6% vs. 27.4%) and a smaller proportion in the precontemplation stage (43.2% vs. 52.3%). CONCLUSION: Although an increase was seen in the proportion of patients being adequately physical active, physical activity levels remain suboptimal in many CHD patients

A first application of the Alcock-Paczynski test to stacked cosmic voids

We report on the first application of the Alcock-Paczynski test to stacked voids in spectroscopic galaxy redshift surveys.We use voids from the Sutter et al. (2012) void catalog, which was derived from the Sloan Digital Sky Survey Data Release 7 main sample and luminous red galaxy catalogs. The construction of that void catalog removes potential shape measurement bias by using a modified version of the ZOBOV algorithm and by removing voids near survey boundaries and masks. We apply the shape-fitting procedure presented in Lavaux & Wandelt (2012) to ten void stacks out to redshift z=0.36. Combining these measurements, we determine the mean cosmologically induced "stretch" of voids in three redshift bins, with 1-sigma errors of 5-15%. The mean stretch is consistent with unity, providing no indication of a distortion induced by peculiar velocities. While the statistical errors are too large to detect the Alcock-Paczynski effect over our limited redshift range, this proof-of-concept analysis defines procedures that can be applied to larger spectroscopic galaxy surveys at higher redshifts to constrain dark energy using the expected statistical isotropy of structures that are minimally affected by uncertainties in galaxy velocity bias.Comment: 11 pages, 8 figures, 1 table, minor revisions from referee comments, ApJ accepte

MVA-based H5N1 vaccine affords cross-clade protection in mice against influenza A/H5N1 viruses at low doses and after single immunization.

Human infections with highly pathogenic avian influenza viruses of the H5N1 subtype, frequently reported since 2003, result in high morbidity and mortality. It is feared that these viruses become pandemic, therefore the development of safe and effective vaccines is desirable. MVA-based H5N1 vaccines already proved to be effective when two immunizations with high doses were used. Dose-sparing strategies would increase the number of people that can be vaccinated when the amount of vaccine preparations that can be produced is limited. Furthermore, protective immunity is induced ideally after a single immunization. Therefore the minimal requirements for induction of protective immunity with a MVA-based H5N1 vaccine were assessed in mice. To this end, mice were vaccinated once or twice with descending doses of a recombinant MVA expressing the HA gene of influenza virus A/Vietnam/1194/04. The protective efficacy was determined after challenge infection with the homologous clade 1 virus and a heterologous virus derived from clade 2.1, A/Indonesia/5/05 by assessing weight loss, virus replication and histopathological changes. It was concluded that MVA-based vaccines allowed significant dose-sparing and afford cross-clade protection, also after a single immunization, which are favorable properties for an H5N1 vaccine candidate

A meta-model for software protections and reverse engineering attacks

Software protection techniques are used to protect valuable software assets against man-at-the-end attacks. Those attacks include reverse engineering to steal confidential assets, and tampering to break the software’s integrity in unauthorized ways. While their ultimate aims are the original assets, attackers also target the protections along their attack path. To allow both humans and tools to reason about the strength of available protections (and combinations thereof) against potential attacks on concrete applications and their assets, i.e., to assess the true strength of layered protections, all relevant and available knowledge on the relations between the relevant aspects of protections, attacks, applications, and assets need to be collected, structured, and formalized. This paper presents a software protection meta-model that can be instantiated to construct a formal knowledge base that holds precisely that information. The presented meta-model is validated against existing models and taxonomies in the domain of software protection, and by means of prototype tools that we developed to help non-modelling-expert software defenders with populating a knowledge base and with extracting and inferring practically useful information from it. All discussed tools are available as open source, and we evaluate their use as part of a software protection work flow on an open source application and industrial use cases

Time trends in lifestyle, risk factor control, and use of evidence-based medications in patients With coronary heart disease in Europe: results from 3 EUROASPIRE surveys, 1999-2013

Background: The EUROASPIRE (European Action on Secondary and Primary Prevention by Intervention to Reduce Events) cross-sectional surveys describe time trends in lifestyle and risk factor control among coronary patients between 1999 and 2013 in Belgium, Czech Republic, Finland, France, Ireland, the Netherlands, Poland, Slovenia, and the United Kingdom as part of the EuroObservational Research Programme under the auspices of European Society of Cardiology. Objectives: This study sought to describe time trends in lifestyle, risk factor control, and the use of evidence-based medication in coronary patients across Europe. Methods: The EUROASPIRE II (1999 to 2000), III (2006 to 2007), and IV (2012 to 13) surveys were conducted in the same geographical areas and selected hospitals in each country. Consecutive patients (≤70 years) after coronary artery bypass graft, percutaneous coronary intervention, or an acute coronary syndrome identified from hospital records were interviewed and examined ≥6 months later with standardized methods. Results: Of 12,775 identified coronary patients, 8,456 (66.2%) were interviewed. Proportion of current smokers was similar across the 3 surveys. Prevalence of obesity increased by 7%. The prevalence of raised blood pressure (≥140/90 mm Hg or ≥140/80 mm Hg with diabetes) dropped by 8% from EUROASPIRE III to IV, and therapeutic control of blood pressure improved with 55% of patients below target in IV. The prevalence of low-density lipoprotein cholesterol ≥2.5 mmol/l decreased by 44%. In EUROASPIRE IV, 75% were above the target low-density lipoprotein cholesterol <1.8 mmol/l. The prevalence of self-reported diabetes increased by 9%. The use of evidence-based medications increased between the EUROASPIRE II and III surveys, but did not change between the III and IV surveys. Conclusions: Lifestyle habits have deteriorated over time with increases in obesity, central obesity, and diabetes and stagnating rates of persistent smoking. Although blood pressure and lipid management improved, they are still not optimally controlled and the use of evidence-based medications appears to have stalled apart from the increased use of high-intensity statins. These results underline the importance of offering coronary patients access to modern preventive cardiology programs