1,459 research outputs found

    Comments on A study of the crystal structure of

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    Primary Invasive Aspergillosis of the Digestive Tract: Report of Two Cases and Review of the Literature

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    Abstract : Background: : Disseminated aspergillosis is thought to occur as a result of vascular invasion from the lungs with subsequent bloodstream dissemination, and portals of entry other than sinuses and/or the respiratory tract remain speculative. Methods: : We report two cases of primary aspergillosis in the digestive tract and present a detailed review of eight of the 23 previously-published cases for which detailed data are available. Results and Conclusion: : These ten cases presented with symptoms suggestive of typhlitis, with further peritonitis requiring laparotomy and small bowel segmental resection. All cases were characterized by the absence of pulmonary disease at the time of histologically-confirmed gastrointestinal involvement with vascular invasion by branched Aspergillus hyphae. These cases suggest that the digestive tract may represent a portal of entry for Aspergillus species in immunocompromised patient

    Efficacité énergétique et émissions de GES de systèmes d'élevage bovin viande en Amazonie.

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    L?élevage au Brésil, 1er exportateur mondial de viande, serait responsable de plus de 75% des déforestations et 19% des émissions nationales de gaz à effet de serre (GES). L?objectif de notre étude est de mettre au point une première méthode de calcul d?efficacité énergétique et d?émissions de GES des systèmes d?élevage amazoniens, en se basant sur la méthode Planète. Une révision de l?ensemble des coefficients énergétiques et des facteurs d?émission de GES ainsi que l?ajout de certaines rubriques ont permis d?élaborer un logiciel de calcul adapté au contexte régional. Six systèmes d?élevage bovin allaitants ont été étudiés lors d?enquêtes directes : un naisseur, trois engraisseurs et deux naisseurs-engraisseurs avec des troupeaux compris entre 650 et 3700 têtes, des charges instantanées variables, liées à des gestions de pâturage et des pratiques alimentaires très diversifiées. Les consommations d?énergie sont en moyenne de 9 724 MJ/t poids vif/an (min=4 019 MJ/t, max=15 243 MJ/t). Les principaux postes, responsables de 56% à 93% des consommations d?énergie, sont les achats d?aliments, la fertilisation des pâturages et l?achat de carburant (et d?animaux pour les engraisseurs). Ces systèmes d?élevage basés sur des ressources herbagères abondantes, utilisant peu d?intrants et d?infrastructures sont peu consommateurs d?énergie, comparés aux autres systèmes dans le monde. Les différences d?efficacité énergétique sont liées à l?efficacité productive végétale et animale et non au degré d?intensité d?utilisation des intrants. Les émissions de GES sont importantes, en moyenne de 19,8 t eq CO2/ t poids vif/ an (min= 11,2 t eq CO2/t, max= 40,5 t eq CO2/t). La déforestation avec un amortissement linéaire sur 20 ans représente de zéro jusqu?à 75% des émissions totales. Nous avons aussi montré l?intérêt environnemental de systèmes productifs intégrant agriculture et élevage. Ces résultats à l?échelle des exploitations participent de la prise de conscience individuelle des éleveurs et renforcent les engagements locaux pour la « déforestation zéro ». La comparaison avec d?autres systèmes d?élevage dans le monde souligne l?intérêt d?une production animale maitrisée, en matière de déforestation et d?intensification, sous les tropiques humides. Plus largement cette étude montre la validité de cette méthode et devrait permettre de généraliser ces bilans

    Differential stress reaction of human colon cells to oleic-acid-stabilized and unstabilized ultrasmall iron oxide nanoparticles.

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    Therapeutic engineered nanoparticles (NPs), including ultrasmall superparamagnetic iron oxide (USPIO) NPs, may accumulate in the lower digestive tract following ingestion or injection. In order to evaluate the reaction of human colon cells to USPIO NPs, the effects of non-stabilized USPIO NPs (NS-USPIO NPs), oleic-acid-stabilized USPIO NPs (OA-USPIO NPs), and free oleic acid (OA) were compared in human HT29 and CaCo2 colon epithelial cancer cells. First the biophysical characteristics of NS-USPIO NPs and OA-USPIO NPs in water, in cell culture medium supplemented with fetal calf serum, and in cell culture medium preconditioned by HT29 and CaCo₂ cells were determined. Then, stress responses of the cells were evaluated following exposure to NS-USPIO NPs, OA-USPIO NPs, and free OA. No modification of the cytoskeletal actin network was observed. Cell response to stress, including markers of apoptosis and DNA repair, oxidative stress and degradative/autophagic stress, induction of heat shock protein, or lipid metabolism was determined in cells exposed to the two NPs. Induction of an autophagic response was observed in the two cell lines for both NPs but not free OA, while the other stress responses were cell- and NP-specific. The formation of lipid vacuoles/droplets was demonstrated in HT29 and CaCo₂ cells exposed to OA-USPIO NPs but not to NS-USPIO NPs, and to a much lower level in cells exposed to equimolar concentrations of free OA. Therefore, the induction of lipid vacuoles in colon cells exposed to OA utilized as a stabilizer for USPIO NPs is higly amplified compared to free OA, and is not observed in the absence of this lipid in NS-USPIO NPs

    New determinations of gamma-ray line intensities of the Ep = 550 keV and Ep = 1747 keV resonances of the 13-C(p,gamma)14-N reaction

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    Gamma-ray angular distributions for the resonances at Ep = 550 keV and 1747 keV of the radiative capture reaction 13-C(p,g)14-N have been measured, using intense proton beams on isotopically pure 13-C targets. Relative intensities for the strongest transitions were extracted with an accuracy of typically five per cent, making these resonances new useful gamma-ray standards for efficiency calibration in the energy range Egamma = 1.6 to 9 MeV.Comment: 17 pages, 6 figures, Nuclear Instruments and Methods, Sec. A, accepte

    Technical and economic feasibility of the capture and geological storage of CO2 from a bio-fuel distillery: CPER Artenay project

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    AbstractThis paper first focuses on the environmental benefits of the CCS system applied to a bio-ethanol distillery before estimating its feasibility under geological and economic constraints.First, the calculation of CO2 balance in this application shows that the introduction of CO2 capture and sto rage in biomass energy systems (B-CCS) can si gnificantly increase the CO2 abat ement potential of the system and even leads to negative carbon emissions. Besides, a preliminary geological investigation reveals that the studied area has a good storage potential although the presence of major faults, while the low capture costs of CO2 from biomass fermentation emphasize the economic potential o f such a solution

    Deep Learning based Modeling of Wireless Communication Channel with Fading

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    In the realm of wireless communication, stochastic modeling of channels is instrumental for the assessment and design of operational systems. Deep learning neural networks (DLNN), including generative adversarial networks (GANs), are being used to approximate wireless Orthogonal frequency-division multiplexing (OFDM) channels with fading and noise, using real measurement data. These models primarily focus on channel output (y) distribution given input x: p(y|x), limiting their application scope. DLNN channel models have been tested predominantly on simple simulated channels. In this paper, we build both GANs and feedforward neural networks (FNN) to approximate a more general channel model, which is represented by a conditional probability density function (PDF) of receiving signal or power of node receiving power Prx: f_p_rx|d(()), where is communication distance. The stochastic models are trained and tested for the impact of fading channels on transmissions of OFDM QAM modulated signal and transmissions of general signal regardless of modulations. New metrics are proposed for evaluation of modeling accuracy and comparisons of the GAN-based model with the FNN-based model. Extensive experiments on Nakagami fading channel show accuracy and the effectiveness of the approaches.Comment: This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl
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