171 research outputs found
Un Atlas de la Nouvelle-CalĂ©donie et de ses communes Ă lâheure du numĂ©rique
Le volume Nouvelle-CalĂ©donie de la Collection Atlas DVD de lâIRD Ă©ditĂ© en partenariat avec le CongrĂšs de la Nouvelle-CalĂ©donie propose, en deux DVD interactifs, une formule originale et trĂšs complĂšte de valorisation des travaux entrepris autour de la rĂ©alisation lâAtlas de la Nouvelle-CalĂ©donie paru en 2012. « LâAtlas numĂ©rique » constitue le premier DVD et permet dâaccĂ©der Ă une version pdf de ce remarquable Atlas qui a mobilisĂ© plus de 70 auteurs autour dâun vaste projet dâactualisation des..
Fractalkine Expression Induces Endothelial Progenitor Cell Lysis by Natural Killer Cells
BACKGROUND: Circulating CD34(+) cells, a population that includes endothelial progenitors, participate in the maintenance of endothelial integrity. Better understanding of the mechanisms that regulate their survival is crucial to improve their regenerative activity in cardiovascular and renal diseases. Chemokine-receptor cross talk is critical in regulating cell homeostasis. We hypothesized that cell surface expression of the chemokine fractalkine (FKN) could target progenitor cell injury by Natural Killer (NK) cells, thereby limiting their availability for vascular repair. METHODOLOGY/PRINCIPAL FINDINGS: We show that CD34(+)-derived Endothelial Colony Forming Cells (ECFC) can express FKN in response to TNF-α and IFN-γ inflammatory cytokines and that FKN expression by ECFC stimulates NK cell adhesion, NK cell-mediated ECFC lysis and microparticles release in vitro. The specific involvement of membrane FKN in these processes was demonstrated using FKN-transfected ECFC and anti-FKN blocking antibody. FKN expression was also evidenced on circulating CD34(+) progenitor cells and was detected at higher frequency in kidney transplant recipients, when compared to healthy controls. The proportion of CD34(+) cells expressing FKN was identified as an independent variable inversely correlated to CD34(+) progenitor cell count. We further showed that treatment of CD34(+) circulating cells isolated from adult blood donors with transplant serum or TNF-α/IFN-γ can induce FKN expression. CONCLUSIONS: Our data highlights a novel mechanism by which FKN expression on CD34(+) progenitor cells may target their NK cell mediated killing and participate to their immune depletion in transplant recipients. Considering the numerous diseased contexts shown to promote FKN expression, our data identify FKN as a hallmark of altered progenitor cell homeostasis with potential implications in better evaluation of vascular repair in patients
Gross tumour volume delineation in anal cancer on T2-weighted and diffusion-weighted MRI - Reproducibility between radiologists and radiation oncologists and impact of reader experience level and DWI image quality
Abstract Purpose To assess how gross tumour volume (GTV) delineation in anal cancer is affected by interobserver variations between radiologists and radiation oncologists, expertise level, and use of T2-weighted MRI (T2W-MRI) vs. diffusion-weighted imaging (DWI), and to explore effects of DWI quality. Methods and materials We retrospectively analyzed the MRIs (T2W-MRI and b800-DWI) of 25 anal cancer patients. Four readers (Senior and Junior Radiologist; Senior and Junior Radiation Oncologist) independently delineated GTVs, first on T2W-MRI only and then on DWI (with reference to T2W-MRI). Maximum Tumour Diameter (MTD) was calculated from each GTV. Mean GTVs/MTDs were compared between readers and between T2W-MRI vs. DWI. Interobserver agreement was calculated as Intraclass Correlation Coefficient (ICC), Dice Similarity Coefficient (DSC) and Hausdorff Distance (HD). DWI image quality was assessed using a 5-point artefact scale. Results Interobserver agreement between radiologists vs. radiation oncologists and between junior vs. senior readers was goodâexcellent, with similar agreement for T2W-MRI and DWI (e.g. ICCs 0.72â0.94 for T2W-MRI and 0.68â0.89 for DWI). There was a trend towards smaller GTVs on DWI, but only for the radiologists (PâŻ=âŻ0.03â0.07). Moderate-severe DWI-artefacts were observed in 11/25 (44%) cases. Agreement tended to be lower in these cases. Conclusion Overall interobserver agreement for anal cancer GTV delineation on MRI is good for both radiologists and radiation oncologists, regardless of experience level. Use of DWI did not improve agreement. DWI artefacts affecting GTV delineation occurred in almost half of the patients, which may severely limit the use of DWI for radiotherapy planning if no steps are undertaken to avoid them
Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences
The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & NemĂ©sio 2007; Donegan 2008, 2009; NemĂ©sio 2009aâb; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported
by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on
18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based
researchers who signed it in the short time span from 20 September to 6 October 2016
Et l'on inventa l'eau chaude et le " blue lagoon " (ou) La découverte récréative des eaux tropicales.
Dans le domaine du tourisme, les eaux tropicales sont associĂ©es, aujourd'hui, Ă une chaleur dĂ©licieuse, des couleurs enchanteresses et des lagons aux poissons multicolores. L'analyse de quelques brochures touristiques confirme que, systĂ©matiquement prĂ©sentĂ©es d'une merveilleuse couleur turquoise, elles participent Ă la dĂ©finition d'une nature tropicale indissociable des vacances de rĂȘve. Pourtant les eaux des tropiques n'ont pas toujours Ă©tĂ© valorisĂ©es. Au XIXe siĂšcle, elles sont le plus souvent absentes des descriptions des voyageurs et des organismes de promotion touristique et elles ne sont pas concernĂ©es par les pratiques de loisirs. Comment les eaux tropicales sont-elles devenues attrayantes ? Cette communication propose de distinguer les trois Ă©tapes de cette invention qui implique une Ă©volution du regard des occidentaux (qui mettent en tourisme le monde) et le dĂ©veloppement de nouvelles pratiques rĂ©crĂ©atives
La construction de lâespace touristique de la Grande BarriĂšre de Corail : entre protection de lâenvironnement et modifications de lâaccessibilitĂ© au rĂ©cif
La Grande BarriĂšre de Corail sâĂ©tend sur 2000 kilomĂštres le long de la cĂŽte orientale de lâĂtat du Queensland en Australie. Chaque annĂ©e, le â Great Barrier Reef Marine Park â, le plus grand parc marin du monde établi en 1975, compte plus de 1,8 millions dâentrĂ©es. Depuis 1981, cet ensemble dâĂźles et de rĂ©cifs est aussi inscrit sur la Liste du Patrimoine mondial de lâUNESCO. La mise en tourisme de la rĂ©gion, qui sâest faite progressivement autour de lâexploitation de cette attraction, nâa pas Ă©tĂ© uniforme.  Ce texte a pour objectif dâaider Ă comprendre la diffĂ©rentiation spatiale du dĂ©veloppement touristique dans la rĂ©gion. Une analyse des changements dans la perception du rĂ©cif montre que lâimportance de la prĂ©occupation environnementale est ancienne dans la gestion de cet ensemble, mais quâelle a Ă©voluĂ©. Lâaugmentation de la frĂ©quentation de la Grande BarriĂšre par les touristes est ensuite replacĂ©e dans le contexte de la croissance du tourisme australien. Enfin lâimportance des conditions techniques et du cadre lĂ©gal de lâaccĂšs aux rĂ©cifs sont envisagĂ©s pour expliquer la polarisation actuelle du dĂ©veloppement autour des zones de Cairns/Port Douglas et des Ăźles Whitsunday.<br>The Great Barrier Reef extends over 2000 kilometres along the eastern coast of Queensland in Australia. Every year, the "Great Barrier Reef Marine Park", the biggest marine park in the world established in 1975, counts more than 1.8 million entries. Since 1981, this group of islands and reefs is also registered on the UNESCO World Heritage List. The touristification of the region, which was gradually achieved around the operation of this attraction, was not uniform. This text has for objective to help to understand the spatial differentiation of the tourist development in the area. An analysis of the changes in the perception of the reef show that the importance of the environmental concern  is well established in the management of this region, but that it has evolved. The increase of the frequentation of the Great Barrier Reef by tourists is replaced in the context of Australian tourism growth. Finally, the importance of the technical conditions and the legal context of access to the reef is envisaged to explain the current polarization of the development around the Cairns / Port Douglas area and Whitsunday Islands area
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