Unexpected sensitivity of the annual net ecosystem exchange to the high frequency loss corrections in a grazed grassland site in Belgium

The eddy covariance technique is widely used to measure CO2 and other gas fluxes. However, eddy covariance fluxes are affected by systematic errors that must be corrected. Among them, high frequency loss corrections are particularly important in this regard, especially when using a closed-path infrared gas analyzer. In this study, we compared three approaches to do these corrections for CO2 fluxes and evaluated their impact on the carbon balance an intensively grazed grassland site in Belgium . In the first approach, the computation of correction factors was based on the measured sensible heat cospectra (‘local’ cospectra), whereas the other two were based on theoretical models (Kaimal et al., 1972). The correction approaches were validated by comparing the nighttime eddy covariance CO2 fluxes corrected with each approach and in situ soil respiration measurements. We found that the local cospectra differed from the Kaimal theoretical shape, although the site could not be considered ‘difficult’ (i.e., fairly flat, homogeneous, low vegetation, sufficient measurement height), appearing less peaked in the inertial subrange. This difference greatly affected the correction factor, especially for night fluxes. Night fluxes measured by eddy covariance were found to be in good accord with in situ soil respiration measurements when corrected with local cospectra and to be overestimated when corrected with Kaimal cospectra. As the difference between correction factors was larger in stable than unstable conditions, this acts as a selective systematic error and has an important impact on annual fluxes. On the basis of a 4-year average, at DTO the errors reach 71-150 g C m-2 y-1 for net ecosystem exchange (NEE), 280-562 g C m-2 y-1 for total ecosystem respiration (TER) and 209-412 g C m-2 y-1 for gross primary productivity (GPP), depending on the approach used. We finally encourage site PIs to check the cospectrum shape at their sites and, if necessary, compute frequency correction factors on the basis of local cospectra rather than on Kaimal cospectra.Bilan carboné d’une exploitation agricole wallonne pratiquant le système allaitant

Inspecting School Social Quality: Assessing and Improving School Effectiveness in the Social Domain

Purpose: School inspection of school social quality is, in contrast to inspection in the cognitive domain, still in its early phase of development. While schools are shown to affect social outcomes, the interplay of mechanisms makes it difficult to isolate the effect of the school. This paper aims to evaluate different approaches to inspecting school social quality. Methodology: Based on a school effectiveness model, we consider what aspects could be taken into consideration to evaluate school social quality. Findings and implications: Using insights from inspection of cognitive outcomes, we present three ideal-type models of inspection, focusing on outcomes, school improvement, or process. There is as of yet no clear best approach to inspecting school social quality, as inspection of school quality can influence school performance in a range of ways. Implications of the described models and possible strengths and weaknesses are discussed

Les effets de la vente en ligne sur les inégalités territoriales d'accès au commerce. Vers un nivellement des disparités urbain-périurbain ?

L’accessibilité géographique des populations aux biens est différenciée selon les espaces. Les populations des centres-villes peuvent accéder à pieds, à proximité de leur domicile à des magasins offrant un large choix de biens, alors que les populations périurbaines doivent parcourir plusieurs kilomètres en voiture pour accéder au premier magasin de proximité. Depuis les années 1990, le commerce à destination des particuliers (business-to-consumer) connaît de fortes évolutions, avec le développement d‘Internet et de la vente en ligne. Cette « électronisation » offre la possibilité d’une séparation croissante des fonctions du commerce, notamment la vente en elle-même et la logistique de distribution . Ainsi, la livraison à domicile et celle dans des relais-livraison se sont affirmées comme des modes de distribution alternatifs aux magasins, bouleversant les cadres de l’analyse de l’accessibilité des populations aux commerces, notamment dans les espaces périurbains. L’accessibilité est entendue ici comme l’ensemble des contraintes spatiales, temporelles et modales pesant sur les déplacements nécessaires pour accéder à un bien.Les principales formes de distribution de la vente en ligne, les livraisons à domicile et en relais-livraison, proposent une redéfinition de l’accessibilité à un large éventail de biens matériels, en offrant ces biens à domicile et/ou dans des commerces de proximité plutôt que, pour certains biens, dans un magasin du centre-ville. Les disparités d’accessibilités aux commerces, parfois fortes selon le type de bien recherché, marquées par un gradient urbain-périurbain et par une hétérogénéité des territoires périurbains, devraient s’en trouver significativement nivelées par une multiplication attendue des points de distribution, notamment dans des territoires qui n’en disposaient pas. Cependant cela nécessite, d’une part, que les habitants des territoires concernés adoptent largement le commerce électronique et tirent parti des options de livraison. D’autre part, le développement de la vente en ligne entraîne une transformation de l’offre commerciale existante par la concurrence qu’elle opère. Certaines localisations commerciales existantes s’en trouvent fragilisées ou remises en cause, tout autant que l’accessibilité et les pratiques d’achat des populations résidant dans ces territoires.Les trois parties du rapport fournissent des réponses et des éclairages différenciés sur ces interrogations, plus précisément sur celle formulée en titre. La première partie sera focalisée sur l'accès aux produits alimentaires et de consommation courante via l'analyse des zones de dessertes des cybermarchés. La seconde partie s'intéressera à un acteur émergent du e-commerce: les points relais. Enfin la dernière partie essaiera de saisir plus finement les usages et pratiques des ménages en termes de ventes en ligne

Pitfall of hepatitis B surface antigen testing in a kidney transplant recipient presenting hepatitis B reactivation

Summary Diagnosis of hepatitis B virus (HBV) infection based on hepatitis B surface antigen (HBsAg) detection can be hampered in the setting of HBV reactivation in immunocompromized patients with prior serology indicating past cured infection, and can be associated with severe or fulminant and fatal hepatitis. We present a case of HBV reactivation in a renal transplant patient in whom HBsAg failed to be confirmed as a true positive result. One year after transplantation, systematic testing showed HBsAg positivity with a titer at 244 pg/mL, anti-hepatitis B core antibody and concurrent anti-hepatitis B surface antibody positivity. Confirmation of HBsAg detection by seroneutralization did not confirm HBsAg positivity, indicating that HBsAg detection was a false positive result. Notwithstanding, HBV DNA titer in serum was concurrently 8.6 Log IU/mL. HBV DNA sequencing showed a genotype D and several amino acid substitutions within HBsAg, including some previously involved in impaired diagnosis and altered immunogenicity. Although no perturbation of liver biochemical markers was observed, treatment with tenofovir was introduced. One month later, HBV DNA level had decreased by 2.6 Log IU/mL and no clinical and biochemical symptoms of hepatitis had occurred. The present case underlines that serologic diagnosis of HBV reactivation can be tricky in transplant recipients with a prior serology indicating past HBV infection. This prompts to perform HBV DNA testing in case of positive HBsAg testing, regardless of the result of neutralization by anti-HBs antibodies

Allegory and animals in Olive Schreiner’s Undine : A Queer Little Child (1929)

Written and abandoned in the 1870s, and published posthumously in 1929, Undine: A Queer Little Child has remained on the margins of Olive Schreiner (1855-1920) studies, repeatedly dismissed as a juvenile and poor antecedent to The Story of An African Farm (1883), or deemed valuable primarily for its autobiographical content. This article redresses these schematic readings by analysing how Schreiner draws on allegorical forms in order to explore aspects of her burgeoning radicalism. Focusing on one of the main allegorical thrusts of the novel, provided by the zoomorphic and anthropomorphic animal characters that descend from mythical, fairytale, and Ancient Greek philosophical origins, it investigates how the protagonist’s metaphorically significant associations with animals relate to freethinking, feminist, and anti-imperialist ideas introduced by the novel. Undine thus undermines dominant nineteenth-century models of the “primitive” human or animal as less evolutionarily developed and without political platform, which can be seen to be a liberating move when the novel is read in dialogue with Jacques Derrida’s lectures on animals, and with other recent work in postcolonial ecocriticism

Management of antiplatelet therapy in patients undergoing elective invasive procedures. Proposals from the French Working Group on perioperative haemostasis (GIHP) and the French Study Group on thrombosis and haemostasis (GFHT). In collaboration with the French Society for Anaesthesia and Intensive Care Medicine (SFAR)

The French Working Group on Perioperative Haemostasis (GIHP) and the French Study Group on Haemostasis and Thrombosis (GFHT) in collaboration with the French Society for Anaesthesia and Intensive Care Medicine (SFAR) drafted up-to-date proposals for the management of antiplatelet therapy in patients undergoing elective invasive procedures. The proposals were discussed and validated by a vote; all proposals but one could be assigned with a high strength. The management of antiplatelet therapy is based on their indication and the procedure. The risk of bleeding related to the procedure can be divided into high, moderate and low categories depending on the possibility of performing the procedure in patients receiving antiplatelet agents (none, monotherapy and dual antiplatelet therapy respectively). If discontinuation of antiplatelet therapy is indicated before the procedure, a last intake of aspirin, clopidogrel, ticagrelor and prasugrel 3, 5, 5 and 7 days before surgery respectively is proposed. The thrombotic risk associated with discontinuation should be assessed according to each specific indication of antiplatelet therapy and is higher for patients receiving dual therapy for coronary artery disease (with further refinements based on a few well-accepted items) than for those receiving monotherapy for cardiovascular prevention, for secondary stroke prevention or for lower extremity arterial disease. These proposals also address the issue of the potential role of platelet functional tests and consider management of antiplatelet therapy for regional anaesthesia, including central neuraxial anaesthesia and peripheral nerve blocks, and for coronary artery surgery.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Gestion des agents antiplaquettaires pour une procédure invasive programmée: propositions du groupe d'intérêt en hémostase périopératoire (GIHP) et du groupe français d’études sur l'hemostase et la thrombose (GFHT) en collaboration avec la Société française d'anesthesie-réanimation (SFAR)

0SCOPUS: re.jinfo:eu-repo/semantics/publishe

Do Perceptions of Costs and Benefits of Post-secondary Education Influence Participation?

Despite the continuing accumulation of knowledge of the factors in- fluencing participation in post-secondary education, there are still gaps in our understanding. For example, very little is known regarding how perceptions of costs and benefits are implicated in an individual’s decision to pursue college or university studies, and whether certain perceptions hamper access among students from disadvantaged backgrounds. This paper presents results from a research programme designed to develop and evaluate an operationalization of “perceived return on investment” (PRoI) in post-secondary education, based on students’ subjective considerations of costs and benefits. These results are derived from two key research questions: is it possible to reliably measure high school students’ perceived return on investment in a post-secondary education, and does the measurement of these perceptions predict actual post-secondary participation? Results show that PRoI can be measured satisfactorily and is predictive of university attendance, net of other factors currently known to influence participation. The “perceptual horizon effect” model is proposed to account for both positive and negative perceptions of returns on investment.  Malgré l’accumulation des connaissances à propos des facteurs qui infl uencent la participation aux études postsecondaires, des lacunes demeurent dans notre compréhension du phénomène. Par exemple, nous en savons peu sur le mécanisme par lequel les perceptions des coûts et des bénéfi ces jouent un rôle dans la décision de poursuivre des études collégiales ou universitaires. De même, on ne sait pas dans quelle mesure certaines perceptions limitent l’accès aux études des jeunes provenant de milieux désavantagés. Cet article présente les résultats d’un programme de recherche ayant pour objectif de développer et d’évaluer l’opérationnalisation des rendements perçus en éducation postsecondaire en se basant sur l’évaluation subjective des coûts et des bénéfi ces par les étudiantes et étudiants. Le projet de recherche est issu de deux questions clés: est-il possible de mesurer de façon fi able les rendements de l’éducation postsecondaire tels que perçus par les élèves du secondaire et est-ce que cette mesure des perceptions peut prédire une éventuelle participation postsecondaire? Les résultats démontrent que les perceptions peuvent être mesurées de façon satisfaisante et peuvent prédire la participation aux études universitaires, et ce en contrôlant pour les autres facteurs connus comme ayant une infl uence sur la participation. Un modèle d’ « horizon perceptuel » est proposé pour expliquer tant les perceptions positives que négatives du retour sur investissement

Les bains de vapeur dans le monde (étude comparative, réactions physiologiques et plantes utilisées)

MONTPELLIER-BU Pharmacie (341722105) / SudocSudocFranceF