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Multicentric prospective evaluation of Pneumocystis jirovecii fungal load in bronchoalveolar lavage fluid fractions using qPCR
No full textInternational audienceBronchoalveolar lavage fluid (BALF) is the key sample type for diagnosing Pneumocystis jirovecii pneumonia, with quantitative PCR (qPCR) providing high sensitivity and specificity. However, sample processing varies considerably between laboratories, and optimal nucleic acid extraction method for BALF remains undetermined. This retrospective multicenter study, conducted in 12 centers as part of the Fungal PCR Initiative, assessed the efficacy of P. jirovecii detection by qPCR in different BALF fractions, including whole (WHO), pellet (PEL), and supernatant (SUP). Samples that were P. jirovecii-qPCR-positive during routine testing were divided into the three predefined fractions prior to nucleic acid extraction and qPCR, comparing detection rates and quantification cycle (Cq) values. Out of 113 P. jirovecii-qPCR-positive BALF samples, 339 qPCR measurements were analyzed. The PEL fraction demonstrated a similar detection rate to the WHO fraction, with positivity rates of 92.9% and 88.5%, respectively. The SUP fraction showed a lower positivity rate of 71.7%, dropping to 47% for high Cq values (Cq>35). Quantitative analysis showed that the SUP fraction consistently yielded higher Cq values, trailing by 3.05 cycles compared to WHO, while PEL showed a smaller deviation (0.49 cycles), confirming its efficiency in retaining P. jirovecii genetic material for qPCR detection. The study concludes that the SUP fraction is suboptimal for P. jirovecii detection due to higher Cq values, suggesting lower fungal loads. The PEL and WHO fractions are comparable, suggesting that the pellet is a viable alternative, permitting the concentration of larger BALF volumes to levels that can be extracted across a range of platforms
RNA-Seq data provide new insights into the molecular regulation of breast muscle glycogen reserves, a key factor in muscle function and meat quality in chickens
No full textInternational audienceResearch is needed to better understand the molecular mechanisms that influence muscle glycogen reserves in chickens due to their critical influence on muscle function and meat quality. In this study, breast muscle RNA sequencing data (RNA-Seq) were used to compare the transcriptomic profile of two original chicken lines divergently selected for breast muscle ultimate pH, which is a proxy for glycogen reserves. Weighted gene co-expression network analysis (WGCNA) of muscle and jejunum RNA-Seq data was also performed to highlight biological processes specifically involved in the gut-muscle dialogue that may contribute to the divergence in glycogen reserves between the two lines. Breast muscle RNA-Seq analysis of 4-week-old birds from the 15th generation of selection, in which glycogen reserves in the pHu-line were twice as high as that in the pHu+ line, revealed 2676 differentially expressed genes (Padj <= 0.05). Functional analysis of the genes overexpressed in the pHu-line highlighted enrichment in processes related to energy production from a wide range of substrates and pathways, as well as to processes involved in development of blood and lymph tissue. Diverse processes were enriched for genes overexpressed in the pHu+ line: muscle development and remodeling, lipid metabolism, immune response and inflammation, which suggested molecular changes much larger than those for carbohydrate metabolism. WGCNA revealed 64 modules of co-expressed genes. One, which contained 30 % genes expressed in the jejunum and 70 % genes expressed in the muscle, was correlated (P <= 0.05) with muscle glycogen reserves and several indicators of intestinal anatomy and health. Functional analysis of it showed an enrichment of processes related to transmission of nerve information and tissue oxygenation that seem to be involved in the gut-muscle dialogue that mediates establishment of breast muscle glycogen reserves. Finally, the study found that transcriptional regulations observed in muscle of the pHu+ line were similar to those in muscle afflicted with "wooden breast", which highlighted a dysfunction of mitochondrial metabolism and suggested several potential gene markers for both conditions
Entre choix et contraintes : décryptage de l’empouvoirement financier chez les femmes entrepreneures en France
No full textInternational audienceThis research examines the empowerment of women entrepreneurs in the context of entrepreneurial financing in France. It explores the factors that allow some women entrepreneurs to access certain categories of external finance more easily. The theoretical framework used is based on the concept of empowerment, explored through its personal and relational dimensions. The study relies on a quantitative approach, using data from a representative of women entrepreneurs. The results show that the status of a founder affects access to external finance in different ways: it increases the chances of successful fundraising, but reduces the chances of obtaining bank finance. This finding highlights the importance of empowerment dynamics, which vary according to the type of financing. In addition, characteristics such as the presence of a spouse in the business, high income, membership of a professional network and the diversity of this network complete the analysis of inequalities in access. This study, the first of its kind in France, suggests ways of enriching our understanding of the diversity of situations experienced by female founders, thus helping to deconstruct the homogeneous image of women’s entrepreneurship.Cette recherche examine l’empouvoirement des entrepreneures dans le cadre du financement entrepreneurial en France. Elle s’interroge sur les facteurs permettant à certaines entrepreneures d’accéder plus facilement à des catégories spécifiques de financement externe. Le cadre théorique mobilisé repose sur le concept d’empouvoirement, exploré à travers ses dimensions personnelle et relationnelle. L’étude s’appuie sur une approche quantitative, utilisant des données issues d’une enquête représentative menée auprès de dirigeantes d’entreprise. Les résultats montrent que le statut de dirigeante fondatrice influence différemment l’accès aux financements externes : il augmente les chances de réussir une levée de fonds, mais réduit celles d’obtenir un financement bancaire. Ce constat souligne l’importance des dynamiques d’empouvoirement, qui varient selon le type de financement. En outre, des caractéristiques telles que la présence du conjoint dans l’entreprise, un revenu élevé, l’appartenance à un réseau professionnel et la mixité de ce réseau complètent l’analyse des disparités d’accès. Cette première étude en France sur ce sujet propose des pistes pour enrichir la compréhension de la diversité des situations vécues par les dirigeantes fondatrices contribuant ainsi à déconstruire l’image homogène de l’entrepreneuriat des femmes
De l’homo viator à l’homo graffitus. Les pratiques du graffiti de visiteurs au contact du patrimoine
No full textInternational audienceVisitor graffiti is part of the informal creation of heritage, but it appeared long before the emergence of the concepts of historic monument and heritage. Since ancient times, travellers, whether anonymous or famous - be they pilgrims, soldiers, artists or even merchants - have readily left a trace of their presence and passage on the places they visited in the form of a signature, name, date, text or drawing. As a form of direct contact, graffiti is inevitably destructive, which in the eyes of contemporary Western society equates it with a form of lèse-patrimoine, or even vandalism. However, this tension has been resolved by recent developments in the way graffiti is perceived, which have opened the way for the practice to be regulated rather than banned. Systems are now in place that make it possible to combine the visitor's expression of graffiti with respect for the integrity of the monument. With the number of tourists visiting our sites and the inevitable deterioration of the stone, this interest in graffiti, past and present, underlines the fragility of these traces, which are now part of our heritage. While digital mediation is helping to renew the relationship between graffiti and heritage, it is also raising questions about the definition and value of authorised graffiti that is virtually in situ.Si le graffiti de visiteurs participe de la fabrique informelle des patrimoines, il apparaît pourtant bien avant l’émergence des notions de monument historique et de patrimonialisation. Depuis l’Antiquité, les voyageurs, anonymes ou célèbres – qu’ils soient pèlerins, soldats, artistes ou encore marchands – ont en effet volontiers laissé la trace de leur présence et de leur passage sur les lieux visités sous la forme de signature, de nom, de date, de texte ou de dessin. Comme contact direct, le graffiti est inévitablement destructif, ce qui l’assimile aux yeux de la société occidentale contemporaine à une forme de lèse-patrimoine, voire de vandalisme. Cette tension trouve cependant sa résolution dans l’évolution récente de la perception du graffiti qui ouvre la voie à un encadrement plutôt qu’à une interdiction de la pratique. Des dispositifs rendent désormais possible cette relation graffitologique mêlant l’expression du visiteur et le respect de l’intégrité du monument. Avec la fréquentation touristique des sites et les inévitables détériorations de la pierre, cet intérêt porté aux graffitis d’hier et d’aujourd’hui souligne la fragilité de telles traces qui font dorénavant l’objet d’une patrimonialisation. Si la médiation numérique contribue à renouveler le rapport entre graffiti et patrimoine, elle interroge également la définition et la valeur d’un graffiti autorisé et virtuellement in situ
"Mise en demeure de l'article 19-2 de la loi du 10 juillet 1965 et irrecevabilité de la demande"
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The impact of ethical logos on purchase intention: the mediating role of product social responsibility
No full textInternational audienceThis paper aims to better understand an increasingly prevalent practice whereby firms affix certified ethical logos (e.g. Fairtrade, 100% organic, Ecolab, etc.) to their products, leveraging perceived product social responsibility (PSR) to enhance purchase intention. Design/methodology/approach A between-subjects experiment was conducted among 484 French consumers, focusing on two brands of chocolate bars. Findings The study reveals a significant increase in purchase intentions when products feature an ethical logo, with PSR acting as a mediator. Additionally, three variables – logo equity, brand equity and the attribution of altruistic motivations to the brand – emerge as significant predictors of PSR in the presence of an ethical logo. Surprisingly, neither the fit between the brand and the logo nor the attribution of strategic motivations influence PSR. Moreover, the impact of PSR on purchase intention is found to be moderated by consumers’ moral identity. Research limitations/implications The research continues and deepens the work of Brown and Dacin (1997) by precisely defining and measuring PSR. In addition, its antecedents are identified, and it is shown that PSR is almost a complete mediator of the identified variables on purchase intention. This result demonstrates that the PSR construct provides both greater explanatory and predictive power than similar concepts and is therefore very useful. The research also contributes to a better understanding of ethical logos as a special kind of brand and sheds light on the complex mechanism of consumers’ attribution. Practical implications From a managerial perspective, this work contributes to explaining why, how and for which target it is relevant to certify consumer goods with ethical logos. Some guidelines on labeling strategy are thus provided. Originality/value This research contributes to the literature on labeling and social responsibility by delineating the concept of PSR, assessing its measurement and identifying its antecedents and consequences for purchase intention
Exactness and the weak containment problem for locally compact groupoids
No full textOur purpose is to study in the setting of locally compact groupoids the analogues of the well-known equivalent definitions of exactness for discrete groups. Our best results are obtained for a class of étale groupoids that we call inner amenable. For locally compact groups this notion coincides with a classical notion of inner amenability. We give examples of such groupoids. Whether all étale groupoids have this property is still unknown. For inner amenable étale groupoids we extend what is known for discrete groups in proving the equivalence of six natural notions of exactness: (1) strong amenability at infinity; (2) amenability at infinity; (3) nuclearity of the uniform algebra of the groupoid; (4) exactness of this C* -algebra; (5) exactness of the groupoid in the sense of Kirchberg-Wassermann; (6) exactness of the reduced C*-algebra of the groupoid. We give several illustrations of these results. One of our motivations for this study of exactness is that it plays a crucial role in examining the relationships between the amenability of a groupoid and the fact that its full and reduced C*-algebras coincide. This is highlighted in the review we give of the results obtained by several authors on this subject. We end our paper with open questions and an appendix on fibrewise compactifications whose study is needed because our work requires to extend from discrete groups to any étale groupoid G the notion of Stone-Čech compactification on which G acts
Solutions analytiques aux équations de Saint-Venant pour les études environnementales et hydrauliques
No full textNew solutions added:- 4 solute solutions (with or without degradation, with initial or boundary dissolved concentration)- 3 mobile rain solutions (depending on the displacement velocity of the rain relatively to the velocity of the flow).Compilation of analytic solutions (in 1d and 2d) for free surface flo
Low back pain reduces reliance on the segment rotation mechanism for postural control in challenging postural conditions
No full textInternational audienceIntroduction. Low back pain (LBP) is considered to alter postural control, yet postural control results remain heterogenous in the LBP population. A potential explanation is that postural control has been predominantly characterised by the 'center of pressure' (CoP) mechanism in non-challenging anatomical conditions, omitting the contribution of the 'segment rotation' mechanism (i.e. modification of whole-body angular momentum). The objective of this study was to characterise the impact of LBP on postural control in non-challenging and challenging bipedal upright postures, using indicators illustrating the contribution of both the CoP and segment rotation mechanisms to postural control. Methods. Twenty adults with chronic LBP and twenty age-matched adults without LBP stood quietly on a forceplate in four postural conditions: anatomical with eyes open, anatomical with eyes closed, tandem with eyes open and tandem with eyes closed. ANOVAs were used to compare indicators illustrating the contribution of the CoP and segment rotation mechanisms between groups and conditions.Results. No difference in indicators of the CoP mechanism were observed between the two groups. Smaller results in mediolateral indicators accounting for the segment rotation mechanism were observed for the LBP group in the tandem with eyes closed condition, compared to the control group.Discussion. These findings suggest that LBP impairs reliance on the segment rotation mechanism (i.e. modification of whole-body angular momentum) for postural control, when its contribution is substantial and cannot be compensated by visual feedbacks. Consequently, the segment rotation mechanism should be quantified complementarily to the CoP mechanism in the LBP population
