O-3, NOY, AND NOX/NOY IN THE UPPER TROPOSPHERE OF THE EQUATORIAL PACIFIC

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Process transparency on construction sites : examples from construction companies in Brazil

Process transparency is the core concept in Visual Management (VM), which is one of the founding blocks of the Toyota Production System. This paper presents the preliminary results of a collaborative research conducted between Brazil and the UK, as part of a research effort focused on the application of Visual Management in construction. How process transparency is realized on construction sites is the main research question of the paper. The use of this concept and the implementation of the transparency theory were investigated through multiple case studies, carried out in nine different construction companies. The findings are explained through six theoretical transparency increasing approaches. The affecting parameters in the application of, the management’s perception of and several methods in process transparency in construction were identified. Further work, especially exploring the functions of process transparency on construction sites and reflecting the worker perception of the issue, is necessary to elaborate the process transparency concept

Determining the date of diagnosis – is it a simple matter? The impact of different approaches to dating diagnosis on estimates of delayed care for ovarian cancer in UK primary care

Background Studies of cancer incidence and early management will increasingly draw on routine electronic patient records. However, data may be incomplete or inaccurate. We developed a generalisable strategy for investigating presenting symptoms and delays in diagnosis using ovarian cancer as an example. Methods The General Practice Research Database was used to investigate the time between first report of symptom and diagnosis of 344 women diagnosed with ovarian cancer between 01/06/2002 and 31/05/2008. Effects of possible inaccuracies in dating of diagnosis on the frequencies and timing of the most commonly reported symptoms were investigated using four increasingly inclusive definitions of first diagnosis/suspicion: 1. "Definite diagnosis" 2. "Ambiguous diagnosis" 3. "First treatment or complication suggesting pre-existing diagnosis", 4 "First relevant test or referral". Results The most commonly coded symptoms before a definite diagnosis of ovarian cancer, were abdominal pain (41%), urogenital problems(25%), abdominal distension (24%), constipation/change in bowel habits (23%) with 70% of cases reporting at least one of these. The median time between first reporting each of these symptoms and diagnosis was 13, 21, 9.5 and 8.5 weeks respectively. 19% had a code for definitions 2 or 3 prior to definite diagnosis and 73% a code for 4. However, the proportion with symptoms and the delays were similar for all four definitions except 4, where the median delay was 8, 8, 3, 10 and 0 weeks respectively. Conclusion Symptoms recorded in the General Practice Research Database are similar to those reported in the literature, although their frequency is lower than in studies based on self-report. Generalisable strategies for exploring the impact of recording practice on date of diagnosis in electronic patient records are recommended, and studies which date diagnoses in GP records need to present sensitivity analyses based on investigation, referral and diagnosis data. Free text information may be essential in obtaining accurate estimates of incidence, and for accurate dating of diagnoses

On the Solutions of Generalized Bogomolny Equations

Generalized Bogomolny equations are encountered in the localization of the topological N=4 SYM theory. The boundary conditions for 't Hooft and surface operators are formulated by giving a model solution with some special singularity. In this note we consider the generalized Bogomolny equations on a half space and construct model solutions for the boundary 't Hooft and surface operators. It is shown that for the 't Hooft operator the equations reduce to the open Toda chain for arbitrary simple gauge group. For the surface operators the solutions of interest are rational solutions of a periodic non-abelian Toda system.Comment: 16 pages, no figure

Analyse du fonctionnement biologique du sol par l'étude de la nématofaune : semis direct versus labour sur les hautes terres près d'Antsirabé (Madagascar)

International audienceLes nématodes du sol possèdent des qualités multiples (abondance, diversité taxonomique et fonctionnelle, existence d'indices liés à l'état du sol) qui en font des indicateurs pertinents du fonctionnement du sol. Ils intègrent un grand nombre d'informations sur l'état de la micro-chaîne trophique du sol (compartiment microbien, microfaune et mésofaune) qui est responsable de la décomposition et de la minéralisation des nutriments. La nématofaune a été analysée dans un essai comparant le semis direct avec restitution des résidus de récolte, au labour avec exportation des résidus de récolte dans une rotation soja/riz sur les hautes terres de Madagascar. Les résultats obtenus durant les deux années d'étude (année en soja & année en riz) ne sont pas significativement différents pour une grande majorité de paramètres nématologiques ce qui signifie qu'à moyen terme de cette expérience (essai mis en place depuis 10 ans), les différences interannuelles liées à la culture sont très inférieures aux différences liées au travail du sol et à la fertilisation. L'absence de travail du sol simultané à la restitution des résidus de récolte, ainsi que la fertilisation minérale et organique, induit une augmentation de l'abondance de la nématofaune tellurique. L'analyse de la composition de la nématofaune indique que les densités de nématodes phytophages d'une part et de nématodes omnivores et prédateurs d'autre part, sont significativement augmentées dans les systèmes en semis direct, alors que les fertilisations organiques et minérales induisent une augmentation de la plupart des groupes trophiques incluant également les microbivores (bactérivores et fongivores). L'analyse des indices nématofauniques montre que le travail du sol ainsi que l'absence de fertilisation sont aussi responsables de la simplification qualitative de la micro-chaîne trophique du sol. Les systèmes en semis direct présentent une nématofaune plus complexe et moins opportuniste incluant des taxons sensibles aux perturbations contrairement au système labouré

Comment instaurer un dialogue efficace entre chercheurs et décideurs sur l’adaptation au changement climatique au Mali

Cette note d’information résume les principales conclusions de l’étude, faite dans le cadre de la plateforme nationale de dialogue science-politique sur le changement climatique, l’agriculture et la sécurité alimentaire, ou plateforme C-CASA créée en 2012, sur l’importance de ce dialogue chercheurs-décideurs et des pistes d’amélioration possibles. Ces conclusions proviennent de l’interview de 17 institutions clés en matière d’adaptation au changement climatique, sélectionnées de façon collective parmi les membres du Comité National Changement Climatique du Mali

A Survey of Information Sources Used for Progress Decisions about Medical Students

Although many medical schools have adopted a variety of methods to assess student competency, the extent to which these innovations have changed how decisions about student progress are made is not clear. This paper describes a survey of 126 accredited allopathic U.S. medical schools to determine which information sources are used for decisions related to medical student progress and graduation. Respondents were asked to indicate up to three information sources used for seven specific decisions about student progress. The results indicate that multiple choice questions (MCQs) and faculty ratings remain the most frequently used information sources. Clinical skills education in the pre-clinical curriculum is the area with the broadest use of assessments for progress decisions. Several explanations are suggested for the primacy of MCQs and faculty ratings in student decisions, including familiarity for faculty and students, ease of implementation and the resources required for the adoption of other assessment strategies

Spectroscopic techniques and the conservation of artists’ acrylic emulsion paints

Artists’ acrylic emulsion paints are used in many contexts such as paintings, murals, sculptures, works on paper and mixed media; and are forming increasing proportions of modern and contemporary art collections. Although acrylic emulsion paints have been the focus of museum-led research over the past decade, the impact of artists’ technique and conservation treatment on the upper-most surface of these paints remains essentially unexplored ; This paper summarises previous studies using vibrational (FTIR) spectroscopy and presents initial assessments of paint surfaces using X-ray spectroscopies (XPS and NEXAFS) aimed at characterising artists’ acrylic paint film surfaces after natural ageing and wet surface cleaning treatment. Both techniques were found to be well suited for surface-sensitive investigations of the organic materials associated with artists’ acrylic paints, including explorations into: (A) cleaning system residues, (B) surfactant extraction from paint surfaces, (C) the identification of migrated surfactant, and (D) monitoring pigment changes at the paint/air interface of paint films ; It has been shown is that these X-ray spectroscopic techniques can be used for the analysis of almost purely organic materials in a way that complements mass spectroscopic techniques, FTIR and XRF. This investigation forms part of broader, currently ongoing, multi-technique investigation into the properties of artists’ acrylic paints and development of conservation treatments for works-of-art made with these materials

Coupled evolution of BrOx-ClOx-HOx-NOx chemistry during bromine-catalyzed ozone depletion events in the arctic boundary layer

Extensive chemical characterization of ozone (O3) depletion events in the Arctic boundary layer during the TOPSE aircraft mission in March-May 2000 enables analysis of the coupled chemical evolution of bromine (BrOx), chlorine (ClOx), hydrogen oxide (HOx) and nitrogen oxide (NOx) radicals during these events. We project the TOPSE observations onto an O3 chemical coordinate to construct a chronology of radical chemistry during O3 depletion events, and we compare this chronology to results from a photochemical model simulation. Comparison of observed trends in ethyne (oxidized by Br) and ethane (oxidized by Cl) indicates that ClOx chemistry is only active during the early stage Of O3 depletion (O3 > 10 ppbv). We attribute this result to the suppression of BrCl regeneration as O3 decreases. Formaldehyde and peroxy radical concentrations decline by factors of 4 and 2 respectively during O3 depletion and we explain both trends on the basis of the reaction of CH2O with Br. Observed NOx concentrations decline abruptly in the early stages Of O3 depletion and recover as O3 drops below 10 ppbv. We attribute the initial decline to BrNO3 hydrolysis in aerosol, and the subsequent recovery to suppression of BrNO3 formation as O3 drops. Under halogen-free conditions we find that HNO4 heterogeneous chemistry could provide a major NOx sink not included in standard models. Halogen radical chemistry in the model can produce under realistic conditions an oscillatory system with a period of 3 days, which we believe is the fastest oscillation ever reported for a chemical system in the atmosphere