Haze in the Klang Valley of Malaysia

Continuous measurements of dry aerosol light scattering (Bsp) were made at two sites in the Klang Valley of Malaysia between December 1998 and December 2000. In addition 24-h PM2.5 samples were collected on a one-day-in-six cycle and the chemical composition of the aerosol was determined. Periods of excessive haze were defined as 24-h average Bsp values greater than 150 Mm-1 and these occurred on a number of occasions, between May and September 1999, during May 2000, and between July and September 2000. The evidence for smoke being a significant contributor to aerosol during periods of excessive haze is discussed and includes features of the aerosol chemistry, the diurnal cycle of Bsp, and the coincidence of forest fires on Sumatra during the southwest (SW) monsoon period, as well as transport modelling for one week of the southwest Monsoon of 2000. The study highlights that whilst transboundary smoke is a major contributor to poor visibility in the Klang Valley, smoke from fires on Peninsular Malaysia is also a contributor, and at all times, the domestic source of secondary particle production is present

A deforestation-induced tipping point for the South American monsoon system

The Amazon rainforest has been proposed as a tipping element of the earth system, with the possibility of a dieback of the entire ecosystem due to deforestation only of parts of the rainforest. Possible physical mechanisms behind such a transition are still subject to ongoing debates. Here, we use a specifically designed model to analyse the nonlinear couplings between the Amazon rainforest and the atmospheric moisture transport from the Atlantic to the South American continent. These couplings are associated with a westward cascade of precipitation and evapotranspiration across the Amazon. We investigate impacts of deforestation on the South American monsoonal circulation with particular focus on a previously neglected positive feedback related to condensational latent heating over the rainforest, which strongly enhances atmospheric moisture inflow from the Atlantic. Our results indicate the existence of a tipping point. In our model setup, crossing the tipping point causes precipitation reductions of up to 40% in non-deforested parts of the western Amazon and regions further downstream. The responsible mechanism is the breakdown of the aforementioned feedback, which occurs when deforestation reduces transpiration to a point where the available atmospheric moisture does not suffice anymore to release the latent heat needed to maintain the feedback

Storende elementen in beeld : de impact van menselijke artefacten op de landschapsbeleving nader onderzocht

Om beleidsopties in beeld te brengen, is de invloed onderzocht van de vormgeving van een drietal doorgaans vrij storende elementen op de impact die deze elementen hebben op de aantrekkelijkheid van het landschap. Het betreft windturbineparken, bedrijventerreinen en grote stallen. Bij alle drie elementen is gekeken naar het effect van mitigerende maatregelen, meestal in de vorm van beplanting, alsmede naar het afstandsverval van de impact. Voor windturbineparken is verder gekeken naar het aantal turbines, de hoogte van de masten en de opstelling. Voor bedrijventerreinen waren dit het soort terrein, de omvang, en de hoogte. Voor grote stallen waren het de lengte en het gebruikte materiaal voor de wanden, respectievelijk het dak. Een en ander is systematisch onderzocht middels foto’s en realistische fotomontages, waarbij een beoordelaar slechts één variant van (een element in) een bepaald landschap voorgelegd kreeg. De beoordelaars waren ruim 2000 leden van een panel van het onderzoeksbureau GfK

Grootschalige landbouw in een kleinschalig landschap : oplossingsrichtingen voor toekomstgerichte grootschalige melkveehouderij uitgewerkt voor het kleinschalige, open veenweidelandschap van Laag Holland

Schaalvergroting wordt door de meeste veehouderijbedrijven gezien als een belangrijke mogelijkheid om de kostprijs te verlagen. Maar vooral in kleinschalige gebieden lopen grotere bedrijven tegen de grenzen van hun omgeving aan. Vanuit de maatschappij klinkt immers de roep om een mooier landschap en hogere natuurwaarden. In de brochure 'Grootschalige landbouw in een kleinschalig landschap' zijn oplossingsrichtingen voor toekomstgerichte grootschalige melkveehouderij uitgewerkt voor het kleinschalige, open veenweidelandschap van Laag Holland

Achieving consensus on minimum data items (including core outcome domains) for a longitudinal observational cohort study in rheumatoid arthritis

Objectives: To obtain consensus on minimum data items for an observational cohort study in rheumatoid arthritis (RA) in the UK and to make available the process for similar studies and other rheumatic conditions. Methods: Individuals with a diverse range of expertise and backgrounds were invited to participate in a process to propose a minimal core dataset (MCD) for research studies, commissioned by Arthritis Research UK as part of the larger INBANK project. The group included patients and representatives from clinical and academic rheumatology, outcomes science, stratified medicine, health economics, national professional and academic bodies/ committees. A process was devised based on Outcome Measures in Rheumatology Clinical Trials (OMERACT) principles to review aims/objectives, definition of scope, identification of important research questions, and selection of key domains. Results: Following the initial multi-stakeholder meeting, subsequent teleconferences and email communications, consensus was obtained on: 1. Most important and relevant research questions; 2. Agreement on how the OMERACT Core Areas (life impact, pathophysiological manifestations, resource use and death) could form the basis of a MCD; 3. Consensus on 22 items for inclusion into a MCD. Workshops were undertaken for two essential items which required further exploration: work/social participation and co-morbidity. Conclusions: Consensus for proposed minimal data items for long-term observational cohort studies of RA in the UK posed novel challenges and opportunities, and was largely successful. Further work is needed to select instruments for two important items and to achieve compatibility with other UK national initiatives, and more widely across Europe

Outcome measures in rheumatoid arthritis randomised trials over the last 50 years

BACKGROUND: The development and application of standardised sets of outcomes to be measured and reported in clinical trials have the potential to increase the efficiency and value of research. One of the most notable of the current outcome sets began nearly 20 years ago: the World Health Organization and International League of Associations for Rheumatology core set of outcomes for rheumatoid arthritis clinical trials, originating from the OMERACT (Outcome Measures in Rheumatology) Initiative. This study assesses the use of this core outcome set by randomised trials in rheumatology. METHODS: An observational review was carried out of 350 randomised trials for the treatment of rheumatoid arthritis identified through The Cochrane Library (up to and including September 2012 issue). Reports of these trials were evaluated to determine whether or not there were trends in the proportion of trials reporting on the full set of core outcomes over time. Researchers who conducted trials after the publication of the core set were contacted to assess their awareness of it and to collect reasons for non-inclusion of the full core set of outcomes in the study. RESULTS: Since the introduction of the core set of outcomes for rheumatoid arthritis, the consistency of measurement of the core set of outcomes has improved, although variation in the choice of measurement instrument remains. The majority of trialists who responded said that they would consider using the core outcome set in the design of a new trial. CONCLUSIONS: This observational review suggests that a higher percentage of trialists conducting trials in rheumatoid arthritis are now measuring the rheumatoid arthritis core outcome set. Core outcome sets have the potential to improve the evidence base for health care, but consideration must be given to the methods for disseminating their availability amongst the relevant communities

Experimental characterization and model identification of directional hardening effects in metals for complex strain path changes

AbstractThe purpose of the current work is the development and application of a new experimental technique and testing device for investigating the complex behavior of sheet metals during non-proportional loading. The method is based on plain strain pure bending, enabling the investigation of large deformation cyclic reversed loading, orthogonal pure bending, as well as springback. The key feature of the pure bending experiment is the absence of contact forces, material slip and friction. Furthermore, during the pure bending test, the strain gradient through the thickness is kinematically prescribed because the specimen is subjected to a plane strain condition in de direction parallel to the rotational axis (Tan et al., 1995), which allows for a straightforward comparison of the pure bending experiments and parallel simulations. The latter is used here via the identification of a recent model for directional hardening effects and arbitrary strain path changes, (Wang et al., 2006, 2008). The current method facilitates experimental investigation of hardening stagnation after reverse loading and cross hardening going well beyond that which is possible with existing methods based on the cyclic shear or tension-shear of sheet metal strips (Bouvier et al., 2005, 2006a,b; Flores et al., 2007.), or pure and three-point bending (Omerspahic et al., 2006; Antonelli et al., 2007; Carbonnière et al., 2009; Yoshida et al., 1998; Weinmann et al., 1988)

Bragg spectroscopy of a superfluid Bose-Hubbard gas

Bragg spectroscopy is used to measure excitations of a trapped, quantum-degenerate gas of 87Rb atoms in a 3-dimensional optical lattice. The measurements are carried out over a range of optical lattice depths in the superfluid phase of the Bose-Hubbard model. For fixed wavevector, the resonant frequency of the excitation is found to decrease with increasing lattice depth. A numerical calculation of the resonant frequencies based on Bogoliubov theory shows a less steep rate of decrease than the measurements.Comment: 11 pages, 4 figure