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V.S.O.P.(99/ 09) represents the further development of V.S.O.P.(99/ 05). Compared to its precursor, the code system has been improved again in many details. The main motivation for this new code version was to update the basic nuclear libraries used by the code system. Thus, all cross section libraries involved in the code have now been based on ENDF/B-VII. V.S.O.P. is a computer code system for the comprehensive numerical simulation of the physics of thermal reactors. It implies the setup of the reactor and of the fuel element, processing of cross sections, neutron spectrum evaluation, neutron diffusion calculation in two or three dimensions, fuel burnup, fuel shuffling, reactor control, thermal hydraulics and fuel cycle costs. The thermal hydraulics part (steady state and time-dependent) is restricted to gas-cooled reactors and to two spatial dimensions. The code can simulate the reactor operation from the initial core towards the equilibrium core.

In any society, a wide diversity of actors has relevant knowledge concerning important societal problems. In a knowledge democracy both dominant and non-dominant actors have equal access and ability to put this knowledge forward in the process of solving societal problems. In order to enable these actors to contribute meaningfully to decision-making around public policy and research agendas, we argue that a transdisciplinary research process is needed. In this chapter we critically reflect on the principles, concepts and core methods of transdisciplinary research. We first look at the national historical roots of transdisciplinary research, specifically focussing on two countries – Switzerland and The Netherlands. Next we develop a typology of transdisciplinary research. From the perspective of knowledge democracy, we can distinguish two important dimensions in research approaches: the degree of knowledge input of lay groups that is included in a specific transdisciplinary project and the degree in which non-dominant actors are explicitly involved in the decision-making of the development process of policies or research agendas. This results in two different styles of transdisciplinary research. We discuss the similarities and differences of these different styles and approaches. We close this chapter with a discussion on transdisciplinary research styles in relation to forms of democracy – on the one hand basic and representative democracy and on the other hand deliberative democracy.

Objective Regular physical activity is associated with decreased morbidity and mortality. Traditionally, patients with rheumatoid arthritis (RA) have been advised to limit physical exercise. We studied the prevalence of physical activity and associations with demographic and disease-related variables in patients with RA from 21 countries. Methods The Questionnaires in Standard Monitoring of Patients with Rheumatoid Arthritis (QUEST-RA) is a cross-sectional study that includes a self-report questionnaire and clinical assessment of nonselected consecutive outpatients with RA who are receiving usual clinical care. Frequency of physical exercise (≥30 minutes with at least some shortness of breath, sweating) is queried with 4 response options: ≥3 times weekly, 1–2 times weekly, 1–2 times monthly, and no exercise. Results Between January 2005 and April 2007, a total of 5,235 patients from 58 sites in 21 countries were enrolled in QUEST-RA: 79% were women, >90% were white, mean age was 57 years, and mean disease duration was 11.6 years. Only 13.8% of all patients reported physical exercise ≥3 times weekly. The majority of the patients were physically inactive with no regular weekly exercise: >80% in 7 countries, 60–80% in 12 countries, and 45% and 29% in 2 countries, respectively. Physical inactivity was associated with female sex, older age, lower education, obesity, comorbidity, low functional capacity, and higher levels of disease activity, pain, and fatigue. Conclusion In many countries, a low proportion of patients with RA exercise. These data may alert rheumatologists to motivate their patients to increase physical activity levels.

BACKGROUND: The Betaferon/Betaseron in newly emerging multiple sclerosis for initial treatment (BENEFIT) trial investigated the effect of treatment with interferon beta-1b after a clinically isolated syndrome. The 5-year active treatment extension compares the effects of early and delayed treatment with interferon beta-1b on time to clinically definite multiple sclerosis (CDMS) and other disease outcomes, including disability progression. METHODS: Patients with a first event suggestive of multiple sclerosis and a minimum of two clinically silent lesions in MRI were randomly assigned to receive interferon beta-1b 250 microg (n=292; early treatment) or placebo (n=176; delayed treatment) subcutaneously every other day for 2 years, or until diagnosis of CDMS. All patients were then eligible to enter a prospectively planned follow-up phase with open-label interferon beta-1b up to a maximum of 5 years after randomisation. Patients and study personnel remained unaware of initial treatment allocation throughout the study. Primary endpoints were time to CDMS, time to confirmed disability progression measured with the expanded disability status scale, and the functional assessment of multiple sclerosis trial outcomes index (FAMS-TOI) at 5 years. Analysis of the primary endpoints was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00185211. FINDINGS: 235 (80%) patients from the early treatment and 123 (70%) from the delayed treatment group completed the 5-year study. Early treatment reduced the risk of CDMS by 37% (hazard ratio [HR] 0.63, 95% CI 0.48-0.83; p=0.003) compared with delayed treatment. The risk for confirmed disability progression was not significantly lower in the early treatment group (0.76, 0.52-1.11; p=0.177). At 5 years, median FAMS-TOI scores were 125 in both groups. No significant differences in other disability related outcomes were recorded. Frequency and severity of adverse events remained within the established safety and tolerability profile of interferon beta-1b. INTERPRETATION: Effects on the rate of conversion to CDMS and the favourable long-term safety and tolerability profile support early initiation of treatment with interferon beta-1b, although a delay in treatment by up to 2 years did not affect long-term disability outcomes. FUNDING: Bayer Schering Pharma. ispartof: The Lancet Neurology vol:8 issue:11 pages:987-997 ispartof: location:England status: published

Bei der Diskussion von Proliterationsrisiken im Bezug auf Kernwaffen werden hauptsächlich Art und Reinheit des Spaltstoffes, die Zündtechnik sowie das Design betrachtet. Neben diesen Aspekten gibt es jedoch noch eine weitere Komponente, die einen wesentlichen Einfluss auf die Wirkung einer Kernwaffe hat: der Neutronenreflektor. Aufgrund seiner besonderen Eigenschaften ist Beryllium die wahrscheinlichste Materialwahl für diese Komponente. Aus den Eigenschaften von Beryllium ergibt sich jedoch auch ein weiteres Feld anderer Anwendungen, sodass die Notwendigkeit besteht, die Produktion und den Handel mit Beryllium einerseits zu kontrollieren, andererseits aber nicht überproportional zu behindern. Aufgrund seiner besonderen Materialeigenschaften ist es auch notwendig, die Standartmethoden zur Detektion zu optimieren. Ein solches Verfahren sowie die weitere Möglichkeiten werden kurz vorgestellt.

Fe isotope ratios are a potentially useful tool to determine the sources of marine dissolved and particulate Fe in the present day ocean and the ocean's redox state of the past. However, to date there are only a few measurements of Fe isotope ratios available from the marine environment. Almost no data exists for dissolved Fe, yet knowledge of the mechanisms and magnitude of Fe isotope fractionation in the marine Fe cycle are essential, if Fe isotope ratios are to be applied to adress either of the above issues. We have analyzed Fe isotope ratios in dissolved and particulate Fe across a depth profile from the anoxic Gotland Basin in the Baltic Sea, sampled during two cruises in 2005. Particulate Fe was measured on MC-ICP-MS using standard bracketing and show δ56Fe values slightly depleted in the heavy isotopes with little variation down the profile. Dissolved Fe was measured with a double spike after co-precipitation with Mg(OH)2. Anoxic samples taken from bottle-casts and filtered in a clean bench may show large offsets in dissolved Fe isotope ratios in comparison to pump-CTD in-line filtered samples, suggesting the likely introduction of artifacts during filtration in contact with air. Particles generally show much higher δ56Fe values than the dissolved phase. Among pump CTD samples, the small number of dissolved Fe samples collected during the first cruise in July at the beginning of the cyanobacteria bloom season show much lower δ56Fe values than those sampled in October, after the bloom. Since neither set of pump CTD samples was exposed to the atmosphere during filtration, an artifact is not likely. Instead, the apparent seasonal difference could be the result of a growing proportion of Fe remineralized from sinking particles of relatively high δ56Fe towards the end of the surface plankton bloom. Prior to and early during the bloom, dissolved Fe at depth may predominatly originate from the basin margin sediments after suboxic early-diagenetic remineralization, for which low δ56Fe values are commonly reported. The apparent seasonal dynamics in Fe isotope ratios may provide useful information regarding the modern marine Fe cycle, but will complicate the use of Fe isotopes as a paleo-redox proxy.

Several studies have been conducted on the presence and diversity of airborne fungal spores in residential and occupational areas. This is the first investigation on this topic in the mining environment. The impact of fungi-especially as opportunistic pathogens-on their health and productivity needs to be assessed, considering the compromised health of a large number of HIV-infected miners in South Africa. Accordingly, the aim of this study was to determine the abundance of fungal spores as well as the diversity of culturable airborne fungi in an active gold mine. The results indicate that three of the sampled sites in the mine contain abundant numbers of culturable airborne fungi. The first site was next to an auxiliary extraction fan, which could act as an accumulator for airborne fungal spores from the rest of the mine. The two other sites had high human activity, disturbances from which may contribute to an elevated fungal load in the air. The presence of timber supports at one site may serve as a growth substrate for several fungal genera. The diversity of filamentous fungal genera increased from outside the mine to deeper into the mine, whereas the diversity of yeast genera followed an opposite trend, with no yeasts detected deep in the mine. Although most of the isolates identified are not pathogens, they could still have a negative impact (either as opportunistic pathogens or allergens) on workers, especially immunocompromised persons if exposed to them for prolonged periods.

Protein phophorylation is a widespread post-translational modification that plays a crucial role in many cellular processes. However the analysis of phosphopeptides and reproducibility of methods is not easy because of many factors, among which relatively low abundance makes it a challenging analytical process.

A Synechococcus sp. strain PCC 7002 Fe bioreporter was constructed containing the isiAB promoter fused to the Vibrio harveyi luxAB genes. Bioreporter luminescence was characterized with respect to the free ferric ion concentration in trace metal-buffered synthetic medium. The applicability of the Fe bioreporter to assess Fe availability in the natural environment was tested by using samples collected from the Baltic Sea and from the high-nutrient, low-chlorophyll subarctic Pacific Ocean. Parallel assessment of dissolved Fe and bioreporter response confirmed that direct chemical measurements of dissolved Fe should not be considered alone when assessing Fe availability to phytoplankton.

In this paper a new FPGA based hardware accelerator (gNBX) for Se(f-Organizing Maps is introduced. New principles for hardware acceleration of Self-Organizing Maps, which increase the degree of paralleliry arid therefore the acceleration gain will be presented. Our technology independent design description can be mapped on application specific integrated circuits if very high performance is required, as well as on Field Programmable Gate Arrays (FPGAS). which offer mid level performance (a speed up factor of up to 70 in comparison with PCs for t)pical datasets is achieved) at relativly low costs. Additional),, FPGAs offer the jlexibility to adapt the hardware to the changing requirements of the application during runtime. Therefore, the hardware can be exploited optimally at all times during the simulati011 process. Several benchmark scenarios with well known datasets will show rheperforniance of our system.

In this paper we present a massively parallel hardware accelerator for neural network based data mining applications. We use Self-Organizing Maps (SOM) for the analysis of very large datasets. One example is the analysis of semiconductor fabrication process data, which demands very high performance in order to achieve acceptable simulation times. Our system consists of Processing Elements (PEs) working completely in parallel on the task of SOM simulation. We will show the scalability of the system concerning precision and number of PEs, as well as the flexibility of the system regarding size and shape of the simulated maps. The possibility of emulating virtual maps (one PE emulates more than one neuron) enables the computation of maps with more neurons than PEs. Benchmarking results of our FPGA (Field Programmable Gate Array) based implementation of the system show the high performance of our accelerator.

We apply the Wigner transform techniques to the analysis of the Dufort-Frankel difference scheme for the Schroedinger equation in the case of a small (scaled) Planck constant (semiclassical regime). In this way we are able to obtain sharp conditions on the spatial temporal grid which guarantee convergence for the average value of observables when the Planck constant tends to zero. The theory developed in this paper is not based on local and global error estimates and does not depend whether caustics develop or not. Numerical tests are presented to help to interpret the theory and to compare the Dufort-Frankel scheme with other difference schemes for the Schrödinger equation.