Hydraulicité dans les piscines thermales. Influence du nombre et de la forme des buses d'arrivée d'eau sur la circulation de l'eau

En vue de maintenir une bonne qualité microbiologique de l'eau minérale de piscines thermales, une étude hydraulique a été menée sur un bassin pilote. Elle a comparé deux configurations différentes quant au nombre et à la forme des buses d'admission d'eau. L'hydraulique est inversée, l'ajout du traceur (rhodamine WT) est instantané, le circuit ouvert. Les résultats montrent que, pour ce bassin, une configuration comprenant 6 buses multidirectionnelles réduit les circuits préférentiels et limite la diffusion d'une pollution localisée en comparaison d'une configuration de 2 buses centrales

Cleanability assessment of model solid surfaces with a radial-flow cell

The cleanability of several model solid substrates (glass, stainless steel, polystyrene and polytetrafluoroethylene-PTFE) was studied with a radial-flow cell. Two soiling methods were used to mimic splashing with oil; a thin layer chromatography sprayer giving a narrower and more reproducible oil droplet size distribution was preferred. Glass was the most cleanable substrate, a result which may be consistent with the presence of a swelling gel-like layer at the surface. For the other substrates, the mechanical action exerted by the fluid played a major role in oil removal; however the detergent seemed to intervene after about 5-10 min, facilitating cleaning of PTFE. Oil droplet removal took place only at high wall shear stress, in zones where flow conditions where not well controlled making it impossible to evaluate the wall shear stresses needed for oil droplet removal. Evaluation of cleanability by using the radial-flow cell is restricted to variations of wall shear stresses in a range below 3 N m(-2). (C) 2007 Elsevier B.V. All rights reserved

Trypanosoma congolense: A comparison of T-cell-mediated responses in lymph nodes of trypanotolerant and trypanosusceptible cattle during primary infection

A comparison of T-cell-mediated immune responses in trypanotolerant N'Dama and susceptible Boran cattle during primary infection with tsetse-transmittedTrypanosoma congolensewas conducted to assess whether different patterns of T-cell activation occurred during trypanosome infection. Proliferation and IFN-γ synthesis in response to trypanosome antigens and to the mitogen Con A were measured in LNC before infection and 10 and 35 days postinfection. Phenotypic analysis of LNC was also carried out. No significant differences in thein vitroproliferation of LNC to VSG, to hsp70/BiP, or to Con A were detected between the breeds. In contrast, IFN-γ production in response to Con A was higher in Boran cattle at 35 days p.i. A reduction in the number of CD2+ and CD4+ T-cells and an increase in the percentage of B-cells, CD8+ T-cells, and γδ T-cells during infection in both N'Dama and Boran was revealed by cytofluorimetric analysis of lymph node cells

Immunisation of cattle with cysteine proteinases of Trypanosoma congolense: Targetting the disease rather than the parasite

In order to test the hypothesis that trypanosome cysteine proteinases (CPs) contribute to pathology of trypanosomosis. cattle were immunised with CPl and/or CP2, the major Cps of Trypanosoma congolense, and subsequently challenged with T. congolense. Immunisation had no effect on the establishment of infection and the development of acute anaemia. However, immunised cattle, unlike control cattle, maintained or gained weight during infection. Their haematocrit and leukocyte counts showed a tendency to recovery after 2-3 months of infection. Cattle immunised with CP2 mounted early and prominent IgG responses to CPs and to the variable surface glycoprotein following challenge. Thus trypanosome CPs may play a role in anaemia and immunosuppression; conversely, anti-CP antibody may modulate the trypanosome-induced pathology

Identifying unknown metabolites using NMR-based metabolic profiling techniques

Metabolic profiling of biological samples provides important insights into multiple physiological and pathological processes, but is hindered by a lack of automated annotation and standardised methods for structure elucidation of candidate disease biomarkers. Here, we describe a system for identifying molecular species derived from NMR spectroscopy based metabolic phenotyping studies, with detailed info on sample preparation, data acquisition, and data modelling. We provide eight different modular workflows to be followed in a recommended sequential order according to their level of difficulty. This multi-platform system involves the use of statistical spectroscopic tools such as STOCSY, STORM and RED-STORM to identify other signals in the NMR spectra relating to the same molecule. It also utilizes 2D-NMR spectroscopic analysis, separation and pre-concentration techniques, multiple hyphenated analytical platforms and data extraction from existing databases. The complete system, using all eight workflows, would take up to a month, as it includes multidimensional NMR experiments that require prolonged experiment times. However, easier identification cases using fewer steps would take two or three days. This approach to biomarker discovery is efficient, cost-effective and offers increased chemical space coverage of the metabolome, resulting in faster and more accurate assignment of NMR-generated biomarkers arising from metabolic phenotyping studies. Finally, it requires basic understanding of Matlab in order to perform statistical spectroscopic tools and analytical skills to perform Solid Phase Extraction, LC-fraction collection, LC-NMR-MS and 1D and 2D NMR experiments

Exploring the potential for planning support systems to bridge the research-translation gap between public health and urban planning

Background: There is consensus that planning professionals need clearer guidance on the features that are likely to produce optimal community-wide health benefits. However, much of this evidence resides in academic literature and not in tools accessible to the diverse group of professionals shaping our cities. Incorporating health-related metrics into the planning support systems (PSS) provides an opportunity to apply empirical evidence on built environment relationships with health-related outcomes to inform real-world land use and transportation planning decisions. This paper explores the role of planning support systems (PSS) to facilitate the translation and application of health evidence into urban planning and design practices to create healthy, liveable communities. Methods: A review of PSS software and a literature review of studies featuring a PSS modelling built environmental features and health impact assessment for designing and creating healthy urban areas was undertaken. Customising existing software, a health impact PSS (the Urban Health Check) was then piloted with a real-world planning application to evaluate the usefulness and benefits of a health impact PSS for demonstrating and communicating potential health impacts of design scenarios in planning practice. Results: Eleven PSS software applications were identified, of which three were identified as having the capability to undertake health impact analyses. Three studies met the inclusion criteria of presenting a planning support system customised to support health impact assessment with health impacts modelled or estimated due to changes to the built environment. Evaluation results indicated the Urban Health Check PSS helped in four key areas: visualisation of how the neighbourhood would change in response to a proposed plan; understanding how a plan could benefit the community; Communicate and improve understanding health of planning and design decisions that positively impact health outcomes. Conclusions: The use of health-impact PSS have the potential to be transformative for the translation and application of health evidence into planning policy and practice, providing those responsible for the policy and practice of designing and creating our communities with access to quantifiable, evidence-based information about how their decisions might impact community health. © The Author(s) 2021

A simulation-based planning support system for creating walkable neighborhoods

Evidence support a link between neighborhoods built environment and modal share of walking. New Planning Support System (PSS) tools for assessing changes in levels of walkability are needed that take advantage of available GIS built environment measures and intelligent simulation techniques. Based on a literature review and an empirical study, a walkability PSS developed in ArcGIS's extension CommunityViz is proposed. Relevance of the walkability PSS is examined through a workshop involving a group of potential users

Functional expression of the catalytic domains of two cysteine proteinases from Trypanosoma congolense

The catalytic domains of two closely related cysteine proteinases (CP l and CP2) from Trypanosoma congolense, referred to as Cl and C2, were expressed as proforms in Escherichia coli (C 1) and in the baculovirus system (C I and C2). While the bacterial expression system did not allow recovery of active C 1, the baculovirus system led to secretion of inactive zymogens which could be processed at acidic pH into mature enzymes. Active Cl and C2 were purified from serum-free culture supernatants by anion-exchange chromatography and characterised. Their kinetic parameters and pH activity profiles confirmed the relatedness between C2 and native CP2 (congopain). These properties also underline major functional differences between Cl and C2, that appear to relate to discrete but essential sequence differences. It is likely that these two enzymes perform distinct roles in vivo, in the parasite and/or in the host-parasite relationships

Trypanosoma congolense: B-Lymphocyte responses differ between trypanotolerant and trypanosusceptible cattle

Trypanosomiasis is a serious constraint to livestock production in sub-Saharan Africa. Some breeds of cattle are genetically more resistant to the pathogenic effects of trypanosome infection. We measured B-cell activation and the quantity and isotype of antibody produced at the cellular level in six trypanotolerant N'Dama and five trypanosuceptible Boran cattle. The frequencies of spleen cells secreting total and parasite-specific IgM and IgG were measured prior to and 16.28 and 35 days after a primary challenge with Trypanosoma congolense. Boran cattle had higher frequencies of splenic cells secreting IgM specific for trypanosome-derived variable surface glycoprotein (VSG), cysteine protease (congopain CP) and heat shock protein (hsp70/BiP) and the nonparasite antigen, ovalbumin, than did N'Dama cattle. In contrast, the number of VSG-specific IgG-secreting cells was significantly greater in N'Dama than in Boran cattle. During infection low titers of anti-BSG IgM were detected in blood than Boran during infection. The peripheral blood mononuclear cell population of N'Dama cattle contained a higher percentage of surface IgM-positive B-cells prior to and throughout infection than were found in the blood of Boran. In addition during infection N'Dama cattle had more circulating lymphocytes that could be activated in vitro to undergo differentiation into IgM- and IgG-secreting cells. These findings demonstrate differences in the frequency of trypanosome-specific antibody-secreting cells in the spleen and in the activation state of B-cells in the blood between N'Dama and Boran cattle during a primary infection with T. congolense

Trypanosoma congolense: B-lymphocyte responses differ between trypanotolerant and trypanosusceptible cattle

Trypanosomiasis is a serious constraint to livestock production in sub-Saharan Africa. Some breeds of cattle are genetically more resistant to the pathogenic effects of trypanosome infection. We measured B-cell activation and the quantity and isotype of antibody produced at the cellular level in six trypanotolerant N'Dama and five trypanosusceptible Boran cattle. The frequencies of spleen cells secreting total and parasite-specific IgM and IgG were measured prior to and 16, 28, and 35 days after a primary challenge withTrypanosoma congolense.Boran cattle had higher frequencies of splenic cells secreting IgM specific for trypanosome-derived variable surface glycoprotein (VSG), cysteine protease (congopain, CP), and heat shock protein (hsp70/BiP) and the nonparasite antigen, ovalbumin, than did N'Dama cattle. In contrast, the number of VSG-specific IgG-secreting cells was significantly greater in N'Dama than in Boran cattle. During infection, low titers of anti-VSG IgM were detected transiently in the serum of all animals. However, N'Dama had significantly more VSG-specific IgG in blood than Boran during infection. The peripheral blood mononuclear cell population of N'Dama cattle contained a higher percentage of surface IgM-positive B-cells prior to and throughout infection than were found in the blood of Boran. In addition, during infection N'Dama cattle had more circulating lymphocytes that could be activatedin vitroto undergo differentiation into IgM- and IgG-secreting cells. These findings demonstrate differences in the frequency of trypanosome-specific antibody-secreting cells in the spleen and in the activation state of B-cells in the blood between N'Dama and Boran cattle during a primary infection withT. congolense