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ABSTRACTThe reduction of greenhouse gas emissions depends largely on the availability of clean energy. To harness solar energy, photovoltaic (PV) materials (solar-grade silicon, germanium, gallium, indium, tellurium, selenium, and arsenic) must be available at a reasonable cost. Markets for these critical and specialty materials do not exceed 200,000 tonnes per year; however, they are subject to fast growth rates. Except for solar-grade silicon, PV materials are by-products of base and precious metal extraction. This is motivated in part by environmental and workplace regulations and the need to purify the main commodity to users’ specifications. Given favorable market conditions, any PV material can be derived from more than one deposit type. For example, germanium can be recovered as a by-product from bauxite, Mississippi Valley-type, clastic-dominated sediment-hosted zinc-lead, Kipushi-type, Apex-type, and other deposit types. The raw materials required to produce metallurgical-grade silicon (MG-Si), mainly quartzites, are available on all continents. The process is energy intensive, so the availability of abundant, inexpensive, and “clean” power is one of the key parameters in selecting future silicon metal plant sites. MG-Si is the starting material for the production of solar-grade silicon. Although no shortages of PV materials due to a lack of raw materials are expected in the short term, those linked to bottlenecks, geopolitical economic considerations, armed conflicts, natural hazards outside of human control, or commercialization of new technology are possible. The advent of the “circular economy” cannot eliminate the need to increase mine, smelter, and refinery production of PV materials.

Le chirurgien vasculaire est confronté quotidiennement au phénomène d’ischémie-reperfusion. En effet, toute intervention chirurgicale nécessitant un clampage artériel induit une situation d’ischémie, qui est ensuite suivie d’une reperfusion au moment du déclampage. L’objectif de ce travail est de faire une mise au point sur la physiopathologie de l’ischémie-reperfusion au niveau du muscle squelettique et de dégager des pistes pour prévenir les lésions d’ischémie-reperfusion dans la pratique clinique courante du chirurgien vasculaire. Les mécanismes contribuant aux lésions d’ischémie-reperfusion sont multifactoriels et complexes. La surcharge calcique et le stress oxydant jouent un rôle majeur, conduisant à l’ouverture du pore de transition de perméabilité mitochondrial. Les mitochondries sont donc une cible privilégiée pour lutter contre les lésions d’ischémie-reperfusion. Le conditionnement ischémique est un processus qui tend à lutter contre les effets délétères de l’ischémie-reperfusion. L’idée est en fait de faire subir à l’organisme de brèves séquences répétées d’ischémie-reperfusion, de façon à stimuler les défenses antioxydantes pour lutter contre une ischémie-reperfusion plus conséquente. Bien qu’offrant des résultats prometteurs en expérimentation animale, le conditionnement ischémique a des résultats plus mitigés au niveau clinique. Néanmoins, avec un protocole bien conduit, dans des situations cliniques adaptées, le conditionnement ischémique pourrait avoir une place majeure. Ainsi, s’il s’avère efficace, une vaste application du conditionnement ischémique s’offrirait aux chirurgiens vasculaires.

Determine the frequency of preconception care use in France and factors impacting preconception visit.

Plusieurs facteurs de risque sont associés au cancer de la prostate, incluant certaines habitudes de vie. Les travaux réalisés par notre équipe ont permis d'associer des éléments de la diète avec le risque de progression de la maladie, ainsi que la présence de certaines bactéries dans la flore intestinale avec l'agressivité du cancer de la prostate. Ce projet vise à déterminer les relations entre les habitudes de vie, le microbiote intestinal et le risque de développer un cancer de la prostate.

Myocardial ischemia-reperfusion injury is a major cause of morbidity and mortality in developed countries. To date, the only treatment of complete ischemia is to restore blood flow; thus the search for new cardioprotective approaches is absolutely necessary to reduce the mortality associated with myocardial ischemia. Ischemia has long been considered to result in necrotic tissue damage but the reduction in oxygen supply can also lead to apoptosis. Therefore, in the last few years, mitochondria have become the subject of growing interest in myocardial ischemia- reperfusion since they are strongly involved in the regulation of the apoptotic process. Indeed, during ischemiareperfusion, pathological signals converge in the mitochondria to induce permeabilization of the mitochondrial membrane. Two classes of mechanisms, which are not mutually exclusive, emerged to explain mitochondrial membrane permeabilization. The first occurs via a non-specific channel known as the mitochondrial permeability transition pore (mPTP) in the inner and the outer membranes causing disruption of the impermeability of the inner membrane, and ultimately complete inhibition of mitochondrial function. The second mechanism, involving only the outer membrane, induces the release of cell death effectors. Thus, drugs able to block or to limit mitochondrial membrane permeabilization may be cytoprotective during ischemia-reperfusion. The objective of this review is to examine the pharmacological strategies capable of inhibiting mitochondrial membrane permeabilization induced by myocardial ischemia-reperfusion.

An insulin receptor-like signaling pathway regulates Caenorhabditis elegans metabolism, development, and longevity. Inactivation of the insulin receptor homolog DAF-2, the AGE-1 PI3K, or the AKT-1 and AKT-2 kinases causes a developmental arrest at the dauer stage. A null mutation in the daf-16 Fork head transcription factor alleviates the requirement for signaling through this pathway. We show here that a loss-of-function mutation in pdk-1, the C. elegans homolog of the mammalian Akt/PKB kinase PDK1, results in constitutive arrest at the dauer stage and increased life span; these phenotypes are suppressed by a loss of function mutation in daf-16. An activating mutation in pdk-1 or overexpression of wild-type pdk-1 relieves the requirement for AGE-1 PI3K signaling. Therefore, pdk-1 activity is both necessary and sufficient to propagate AGE-1 PI3K signals in the DAF-2 insulin receptor-like signaling pathway. The activating mutation in pdk-1 requires akt-1 and akt-2 gene activity in order to suppress the dauer arrest phenotype of age-1. This indicates that the major function of C. elegans PDK1 is to transduce signals from AGE-1 to AKT-1 and AKT-2. The activating pdk-1 mutation is located in a conserved region of the kinase domain; the equivalent amino acid substitution in human PDK1 activates its kinase activity toward mammalian Akt/PKB.

The binding profile of Actinobacillus pleuropneumoniae serotypes 1 and 2 to various glycosphingolipids was evaluated by using thin-layer chromatogram overlay. A. pleuropneumoniae whole cells recognized glucosylceramide (Glcbeta1Cer), galactosylceramide (Galbeta1Cer) with hydroxy and nonhydroxy fatty acids, sulfatide (SO(3)-3Galbeta1Cer), lactosylceramide (Galbeta1-4Glcbeta1Cer), gangliotriaosylceramide GgO3 (GalNAcbeta1-4Galbeta1-4Glcbeta1Cer), and gangliotetraosylceramide GgO4 (Galbeta1-3GalNAcbeta1-4Galbeta1-4Glcbeta1Cer) glycosphingolipids. We observed no binding to globoseries, globotriaosylceramide Gb3, globoside Gb4, or Forssman Gb5 glycosphingolipids or to gangliosides GM1, GM2, GM3, GD1a, GD1b, GD3, and GT1b. The A. pleuropneumoniae strains tested also failed to detect phosphatidylethanolamine or ceramide. Interestingly, extracted lipopolysaccharide (LPS) of serotype 1 and serotype 2 as well as detoxified LPS of serotype 1 showed binding patterns similar to that of whole bacterial cells. Binding to GlcCer, GalCer, sulfatide, and LacCer, but not to GgO3 and GgO4 glycosphingolipids, was inhibited after incubation of the bacteria with monoclonal antibodies against LPS O antigen. These findings indicate the involvement of LPS in recognition of three groups of glycosphingolipids: (i) GlcCer and LacCer, where glucose is probably an important saccharide sequence required for LPS binding; (ii) GalCer and sulfatide glycosphingolipids, where the sulfate group is part of the binding epitope of the isoreceptor; and (iii) GgO3 and GgO4, where GalNacbeta1-4Gal disaccharide represents the minimal common binding epitope. Taken together, our results indicate that A. pleuropneumoniae LPS recognize various saccharide sequences found in different glycosphingolipids, which probably represents a strong virulence attribute.

A neurosecretory pathway regulates a reversible developmental arrest and metabolic shift at the Caenorhabditis elegans dauer larval stage. Defects in an insulin-like signaling pathway cause arrest at the dauer stage. We show here that two C. elegans Akt/PKB homologs, akt-1 and akt-2, transduce insulin receptor-like signals that inhibit dauer arrest and that AKT-1 and AKT-2 signaling are indispensable for insulin receptor-like signaling in C. elegans. A loss-of-function mutation in the Fork head transcription factor DAF-16 relieves the requirement for Akt/PKB signaling, which indicates that AKT-1 and AKT-2 function primarily to antagonize DAF-16. This is the first evidence that the major target of Akt/PKB signaling is a transcription factor. An activating mutation in akt-1, revealed by a genetic screen, as well as increased dosage of wild-type akt-1 relieves the requirement for signaling from AGE-1 PI3K, which acts downstream of the DAF-2 insulin/IGF-1 receptor homolog. This demonstrates that Akt/PKB activity is not necessarily dependent on AGE-1 PI3K activity. akt-1 and akt-2 are expressed in overlapping patterns in the nervous system and in tissues that are remodeled during dauer formation.

Résumé: Deux lignées cellulaires ont été établies à partir d'ovarioles provenant de chrysalides du lépidoptèreSpodoptero littoralis Boisduval, important revageur de cultures. Leur sensibilité à des Densovirus et des Baculovirus, virus utilisés en lutte microbiologique est à noter et permet d'envisager des travaux de pathologie jusqu'ici limités par l'absence de systèmes cellulaires permissifs.

Electron microprobe analyses of minerals in low grade metamorphic sandy black shales of middle Paleozoic age indicate that chemical equilibrium was closely approached in authigenic ferro-magnesian or alkali-bearing phases while aluminum silicate minerals appear to have reacted at a slower rate. The K for Mg-Fe in chlorite-chloritöid pairs is 0.19, the latter phase being iron-rich. The pseudomorphism of detrital white micas produces kaolinite, pyrophyllite and intimate mixtures of muscoviteparagonite. New phases forming in other sites include chlorite, chloritöid and rectorite which is an ordered paragonitebeidellite mixed layered phase. These minerals were formed at temperatures below 280° C. This is just above the stability of the illite-smectite mixed layered minerals which have an ISII ordering sequence (85 to 95% illite). It was noted that ferromagnesian minerals attain chemical equilibrium on a thin-section scale while the aluminous phases often seem to respond to chemical potentials operative on a submillimetric scale.

Abstract: Trois Baculovirus isolés de larves deSpodoptera littoralis atteintes de polyédroses nucléaires au Maroc, en Egypte et dans un élevage à Lyon ont été comparés par analyse de leurs génomes avec des enzymes de restriction. Les variants génétiques contenus dans les populations virales sont obtenus après isolement de clones en culture cellulaire. Sur 27 clones analysés par les endonucléases on observe 11 variants avecEco RI, 3 variants avecBam HI et avecSac I et un type unique avecHin dIII. Les 3 virus Maroc, Egypte et Lyon sont différents, mais appartiennent à l'espèce B définie parCherry & Summers (1985). Summary: Three Baculoviruses were isolated fromSpodoptera littoralis larvae infected with nuclear polyhedrosis (NPV) collected from Morocco, Egypt, and a from laboratory culture at Lyon (France). Their genomes were compared by restriction endonuclease analysis. The genotypic variants contained in the viral populations were obtained after isolation of clones in cell culture. Among the 27 clones analyzed by restriction endonucleases, 11 variants were observed withEco RI, 3 variants withBam HI andSac I, and one unique type withHin dIII. These 3 viruses “Morocco”, “Egypt”, and “Lyon” are different, but belong to type B ofS. littoralis NPV as defined byCherry & Summers (1985).

Actinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia. The major adhesin of A. pleuropneumoniae has been identified as the lipopolysaccharides (LPSs) (M. Bélanger, D. Dubreuil, J. Harel, C. Girard, and M. Jacques, Infect. Immun. 58:3523-3530, 1990). Using immunoelectron microscopy and flow cytometry, we showed in the present study that LPSs were well exposed at the surface of this encapsulated microorganism. Immunolocalization with porcine lung and tracheal frozen sections showed that extracted LPS bound to the lung mesenchyme and vascular endothelium and to the tracheal epithelium, respectively. Inhibition of adherence of A. pleuropneumoniae with extracted LPS was also performed with lung and tracheal frozen sections. Acid hydrolysis of LPS revealed that the active component of LPS was not lipid A but the polysaccharides. LPSs from A. pleuropneumoniae serotypes 1 and 2 were separated by chromatography on Sephacryl S-300 SF, in the presence of sodium deoxycholate, according to their molecular masses. The adherence-inhibitory activity was found in the high-molecular-mass fractions. These high-molecular-mass fractions contained 2-keto-3-deoxyoctulosonic acid and neutral sugars, and they were recognized by a monoclonal antibody directed against A. pleuropneumoniae O antigen but not recognized by a monoclonal antibody against capsular antigen.

Binding of pig hemoglobin (Hb) to Actinobacillus pleuropneumoniae lipopolysaccharide (LPS), either extracted or present at the surface of whole cells, was studied. After a short incubation period, pig Hb seemed to cover the bacterial cell surface and enhanced the cells' contrast when examined by transmission electron microscopy (TEM). Energy-dispersive X-ray spectroscopy analysis showed that the amount of elemental iron detected was increased when cells of A. pleuropneumoniaewere incubated with pig Hb. Coating with pig Hb, however, did not interfere with the accessibility of O- and capsular antigens to antibodies on the bacterial cell surface. Binding of pig Hb and polymyxin B to lipid A of A. pleuropneumoniaewas confirmed with a fluorescent probe (dansylcadaverine) displacement assay. The binding of pig Hb to extracted LPS resulted in a disaggregation of LPS as observed by TEM after negative staining. Additional evidence for a direct physical interaction between pig Hb and A. pleuropneumoniaeLPS was demonstrated by a shift in the sedimentation velocity of LPS-Hb complexes determined by sucrose gradient centrifugation. Pig Hb binding to extracted LPS or to bacterial cells resulted in a significant decrease of chromogenic Limulus amebocyte lysate activation. Finally, the capacity of extracted LPS to induce NO2-in the presence of pig Hb was tested by using cell line J774 and determined by the Greiss' reaction. LPS alone induced, as expected, NO2- production, whereas the presence of pig Hb significantly reduced NO2-production by murine macrophages. Taken together, our results indicate that binding of pig Hb affected some physical and biological properties of A. pleuropneumoniaeLPS.

Résumé: Grâce à la mise au point d’une méthode intermédiaire entre l’infection d’Invertébrés vivants et la culture cellulaire, de grandes quantités de virions et de corps d’inclusions de polyédroses nucléaires ont été produitsin vitro sur tissus de Lépidoptères maintenus en survie pendant quelques jours. Ce principe et cette méthode de production peuvent être exploités pour l’analyse des virus et pour la lutte microbiologique.

Bottom trawling grounds have been expanding to deeper areas of the oceans since the mid‐XXth century, and mitigating strategies aimed to protect fish stocks, such as temporal trawling closures, have recently been implemented. Here we investigated the biogeochemical properties of sediment from a deep‐sea trawling ground in Palamós Canyon (NW Mediterranean) to assess the effects of a 2‐months trawling closure in the recovery of sedimentary organic matter. In comparison to untrawled areas, the continuous erosion and sediment mixing in trawling grounds led to coarser reworked sediments impoverished in organic carbon (∼30% loss) and promoted the degradation of labile compounds (52–70% loss). These impacts persisted after the temporal trawling closure, highlighting that this management strategy is insufficient to restore the seafloor. Considering the continuous expansion of bottom trawling grounds, this activity could have significant and irreversible biogeochemical impacts on ocean margins at a global scale, hampering their carbon burial capacity. Bottom trawling grounds have been expanding to deeper areas of the oceans since the mid‐XXth century, causing substantial effects to fish populations. In order to reduce this impact, new management strategies have been introduced, such as establishing temporal trawling closures to allow fish populations to recover. Bottom trawling not only poses a threat to fish populations but also to the seafloor, since the continuous contact of trawling gear on the bottom erodes large volumes of sediment and reduces the amount and quality of organic matter. In this study, we assessed the effect of a 2‐months trawling closure in deep‐sea bottom trawling grounds in Palamós Canyon (NW Mediterranean) by collecting sediment samples in trawled and untrawled areas during different seasons. Our results show that sediment samples in the trawled site had substantially lower organic matter contents than in the untrawled site, and the remaining organic matter had poor nutritional quality. These impacts persisted after the temporal trawling closure, highlighting that this management strategy is insufficient to restore the seafloor. Considering the continuous expansion of bottom trawling grounds, this activity could have significant and irreversible impacts in organic matter available for benthic species in ocean margins at a global scale. Bottom trawling disturbance on the deep seafloor depletes organic matter through erosion and degradation, hampering its preservationA 2‐month seasonal trawling closure is insufficient to restore the seafloor and it is estimated that it would take decades to recoverBottom trawling causes organic carbon losses from the seafloor comparable to those generated on land by tillage of agricultural fields Bottom trawling disturbance on the deep seafloor depletes organic matter through erosion and degradation, hampering its preservation A 2‐month seasonal trawling closure is insufficient to restore the seafloor and it is estimated that it would take decades to recover Bottom trawling causes organic carbon losses from the seafloor comparable to those generated on land by tillage of agricultural fields

Summary: A new cell line, designated SPC G1 13, derived from dorsal vessels of larvae ofGromphadorhina laevigata has been established. The medium used is D. 73. The cells are fibroblastlike cells. Some of them are fixed; others, spindle-shaped or round, are in suspension. Most of the cells have the diploid chromosome number. The SPC G1 13 cell line is permissive to the chlamydiaRickettsiella grylli

In this paper, we review and present the results of carbon nanotubes syntheses using variety of CVD and PECVD techniques that are available in our laboratories. The techniques included Joule-heating CVD, floating catalyst CVD, conventional thermal CVD, aerosol-assisted CVD, spray pyrolysis CVD, radio frequency plasma enhanced CVD (PECVD) and microwave plasma enhanced CVD. Influences of synthesis methods on the CNTs growth have been compared and discussed. The synthesized CNTs have been characterized by various techniques, including Raman Spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). These studies are expected to pave the way to develop strategies for controlled synthesis of CNTs tailored for specific applications, including sensors and nanodevices.