Acclimatation d'une biomasse anaérobie à un effluent de fabrication d'une pâte à papier à concentration élevée en composés soufrés

L'effluent de fabrication à partir de bois de résineux d'une Pâte Chimico-Thermo-Mécanique (CTMP) contenant des dérivés soufrés organiques et des sulfates, est très difficilement épuré par voie anaérobie. La présente étude montre qu'il est indispensable d'acclimater la biomasse à de fortes concentrations en soufre dans l'effluent. Ceci est réalisé en alimentant un réacteur à biomasse fixée (pilote de laboratoire), en fonctionnement continu, par des mélanges d'un effluent de distillerie et de l'effluent CTMP, dans lesquels la proportion du second est augmentée par paliers successifs jusqu'à 100 %.On peut alors finalement obtenir une épuration convenable de l'effluent CTMP à des teneurs en soufre jusqu'à 500 mg/l (pourvu que le rapport DCO/S soit supérieur à 10 environ).Anaerobic treatment of wastewater from chemico-thermomechanical pulping (CTMP) of softwoods was inhibited by sulphur containing compounds. Distillery skips are characterized by a high sulphur content and a more appropriate COD/sulphur ratio than CTMP wastewater. Using CTMP wastewater together with distiliery stops during initial starting up resulted in successful acclimatation of microorganisms to significant sulphate contents.Provided the COD/Sulphur was aboue 10 reasonably good treatment efficiency was obtained with CTMP wastewater containing to 500 mg total sulphur per liter

From dereplication and anti-inflammatory screening of Clusiaceae and Calophyllaceae species to novel immunomodulatory coumarins from Mesua lepidota

Vascular endothelium plays a central role in the development of inflammatory and immune processes, which are involved in graft rejection1. Many Clusiaceae/Calophyllaceae species (pantropical plants) biosynthesize original polyphenolic compounds exhibiting antioxidant and anti-inflammatory properties2-3. Bark, leaves and occasionally fruits from thirteen Malaysian plants belonging to the genus Calophyllum, Mesua (Calophyllaceae), Garcinia (Clusiaceae) were extracted using DCM and MeOH as the solvents. Each extract was then submitted to a HPLC-PDA-MSn dereplication analysis and its anti-inflammatory potential was evaluated on Human Umbilical Vein Endothelial Cells (HUVECs). This allowed to select the bioactive fruits DCM extract of Mesua lepidota T. Anderson for an advanced phytochemical study, which led to the identification of several new coumarin derivatives. A flow cytometry study revealed that the major component of this extract, namely lepidotol A (1), significantly inhibited the VCAM-1, HLA-II and HLA-E expression of HUVECs previously activated by TNF-α or IFN-γ cytokines.   References   1.     P. T. Clesca, Int. Congr. Ser., 2002, 1237, 181-191. 2.     F. V. Cechinel, C. Meyre-Silva, and R. Niero, Chem. Biodivers., 2009, 6, 313-327. 3.     J. González-Gallego, M. V. García-Mediavilla, S. Sánchez-Campos and M. J. Tuñón, Br. J. Nutr., 2010, 104, S15-S2

Effets anti-inflammatoire et immunomodulateur de composés polyphénoliques isolés de Clusiaceae et de Calophyllaceae

L’endothélium vasculaire joue un rôle central dans le développement des réponses inflammatoires et immunitaires conduisant notamment au phénomène de rejet de greffe1. Les Clusiaceae et Calophyllaceae, plantes des régions pantropicales, biosynthétisent des dérivés polyphénoliques originaux présentant des activités anti-inflammatoires intéressantes2-3. Divers polyphénols isolés de ces plantes ont été sélectionnés, afin d’évaluer in vitro leur potentiel anti-inflammatoire et immunomodulateur sur des cellules endothéliales humaines. Plusieurs coumarines et une benzophénone se sont alors révélées inhibitrices de l’expression de marqueurs de l’inflammation et de l’immunité. Parallèlement à cette étude, les extraits dichlorométhaniques (DCM) et méthanoliques d’un panel de plantes issues des genres Garcinia (Clusiaceae), Calophyllum et Mesua (Calophyllaceae), originaires de Malaisie, ont été analysés par déréplication (HPLC-PDA-MSn). Deux extraits contenant des pharmacophores d’intérêt ont ainsi été sélectionnés pour une étude phytochimique approfondie : l’extrait DCM de fruits de Mesua lepidota, duquel ont été identifiés sept phénylcoumarines originales, que nous avons baptisées lépidotols et lépidotines, et l’extrait DCM de feuille de Calophyllum tetrapterum, ce dernier riche en benzophénones polyprénylées. Références : 1.         Brick C, Atouf O, Benseffaj N, et al. Rejet de la greffe rénale : mécanisme et prévention. Nephrol Ther 2011;7:18-26. 2.         Ali M, Arfan M, Ahmad M, et al. Anti-inflammatory xanthones from the twigs of Hypericum oblongifolium Wall. Planta Med 2011;77:2013-2018. 3.         Santa-Cecilia FV, Freitas LAS, Vilela FC, et al. Antinociceptive and anti-inflammatory properties of 7-epiclusianone, a prenylated benzophenone from Garcinia brasiliensis. Eur J Pharmacol 2011;670:280-285

Non-volatile tuning of normally-on and off states of deep depletion ZrO2/O-terminated high voltage diamond MOSFET

Based on the stability of the deep depletion regime in diamond and the outstanding properties of this promising material for its use in power devices, p-channel deep depletion metal oxide semiconductor field effect transistors were fabricated on a (001) Ib nitrogen-doped high pressure high temperature diamond substrate. Taking advantage of the new concept of the non-volatile diamond-based photo switch, it is demonstrated that it is possible to tune the normally-on and normally-off states of the transistor by configuring the pn-junction space charge region. The devices under study was designed following an interdigital-like and a circular-like architectures presenting low threshold voltages (between 3 V and −3 V), an on/off ratio of 107 and a critical electric field numerically assessed of 9 MV.cm−1 at room temperature. This new degree of freedom opens the route for diamond based power electronics.8 página

Usefulness of Parent-Completed ASQ for Neurodevelopmental Screening of Preterm Children at Five Years of Age.

International audienceINTRODUCTION: Preterm children are at greater risk of developmental impairment and require close follow-up for early and optimal medical care. Our goal was to examine use of the parent-completed Ages and Stages Questionnaire (ASQ) as a screening tool for neurodevelopmental disabilities in preterm infants at five years of age.PATIENTS AND METHODS: A total of 648 preterm children (285 were not distinctive for mild delay or normal development. In children with developmental delay, no difference was found when ASQ scores according to maternal education levels were analyzed.CONCLUSIONS: ASQ at five years is a simple and cost-effective tool that can detect severe developmental delay in preterm children regardless of maternal education level, while its capacity to identify children with mild delay appears to be more limited

MATE, a single front-end ASIC for silicon strip, Si(Li) and CsI detectors

MATE (Must ASIC for Time and Energy) will process signals delivered from the hodoscope MUST2. The hodoscope consists of six large area telescopes (100 cm²), each made up of a double sided Si strip detector followed by a Si(Li) and Csi crystal. MATE has sixteen channels and can deliver three types of analogue information per channel; time of flight and energy loss of the detected particle; value of leakage DC current per channel. MATE also gives a trigger logical signal corresponding to the cross over of an adjustable threshold value. The analogue information is transmitted as differential current through twisted pair to the acquisition system based on VXI-C. The slow control is assured via the I2C industrial protocol. The first version of MATE for Si(strip) is available. An update of MATE will allow it to be used for the Si(Li) and Csi detectors. MATE is a novel R&D project for nuclear physics which includes both energy and time measurements with good resolution and high energy dynamic range

Selection of Clusiaceae and Calophyllaceae extracts based on dereplication and anti-inflammatory properties

Inflammation is associated with many pathogenic disorders including endothelial dysfunction. Calophyllaceae and Clusiaceae which are rich in polyphenolic compounds such as coumarins, xanthones, benzophenones and biflavonoids1 are well-known for their anti-inflammatory properties2. Bark, leaves and occasionally fruits of thirteen plants belonging to the genus Calophyllum, Mesua (Calophyllaceae), Garcinia (Clusiaceae) and native from Malaysia, were extracted using DCM and MeOH as the solvents. Extracts of interest were selected according to two distinct criteria. Firstly, a dereplication analysis was conducted though HPLC-PDA-MSn. Secondly the VCAM-1 surface-expression of (TNF-α)-stimulated endothelial cells from human umbilical veins (HUVECs) was evaluated. It appeared that several extracts particularly rich in xanthones and phenylcoumarins significantly decreased inflammatory marker expression. In this context, a new phenylcoumarin was identified as the major component of the bioactive fruits DCM extract from a Mesua. References: [1] V. Cechinel Filho et al. Chem. Biodivers. 2009, 6, 313-327 [2] J. Gonzalez-Gallego et al. Br. J. Nutr. 2010, 104, S15-S2

Anti-inflammatory and immunomodulatory properties of polyphenolic compounds from Clusiaceae/Calophyllaceae: A focus on coumarins

Vascular endothelium plays a central role in the development of inflammatory and immune processes, which are involved in graft rejection [1]. Many Clusiaceae/Calophyllaceae species (pantropical plants) biosynthesize original polyphenolic compounds exhibiting antioxidant and anti-inflammatory properties [2 – 3]. Therefore, different Clusiaceae/Calophyllaceae polyphenols were selected in order to evaluate in vitro their anti-inflammatory and immunomodulatory potential towards Human Umbilical Vein Endothelial Cells (HUVECs). The VCAM-1, ICAM-1, E-selectin, HLA-I, HLA-II, HLA-E and MICA surface-expressions of HUVECs were evaluated by flow cytometry. It appeared that a few coumarins and one benzophenone at 10µM significantly inhibited the expression of several markers previously induced by TNF-α or IFN-γ cytokines, being more active that the immunosuppressive reference compound – zoledronic acid – at the same concentration. Among these active compounds, one phenylcoumarin isolated from the Malaysian Mesua lepidota T. Anderson (Calophyllaceae) was identified as a new one. By comparing biological effects with substitution patterns, preliminary structure-activity relationship was also established