2,272 research outputs found

    Microfibrous TiO2 supported photocatalysts prepared by metal-organic chemical vapor infiltration for indoor air and waste water purification

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    The photocatalytic degradation of gaseous (toluene) and aqueous (imazapyr, malic acid, orange G) pollutants over TiO2 supported photocatalysts is investigated using a batch reactor. A strong influence of the microstructural characteristics of TiO2 on the decomposition kinetics of the pollutants is found. Well crystallized, porous TiO2-anatase films grown under low pressure at 400–500 8C by MOCVD on glass plates and by MOCVI on glass micro-fibers are the best heterogeneous photocatalysts, showing the highest activity. We demonstrate a good control of these characteristics by choosing the deposition parameters. Achieving conformal coverage (i.e. good infiltration) of glass micro-fibers by the TiO2 thin films has also a strong influence on the photocatalytic activity. A correlation between optimal infiltration, film microstructure and photocatalytic activity is established. Strong similarities between optimal photocatalytic decomposition rate in gas and liquid phase were found with respect to the film microstructure and the photocatalyst mass. The total mineralization of the toluene was prevented because of the deactivation of the photocatalyst surface. However the reactivation of the photocatalyst was achieved by UV irradiation under oxygen stream. This allows a long-term use of the photocatalyst

    Enhancing UX of analytics products with AI technology

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    [EN] Insights and knowledge extraction from conventional analytics or reporting solutions is mostly neither trivial, nor intuitive. Moreover, many applications have unique interfaces and operating controls, forcing users to understand the tool’s domain language and handling procedures, in order to find specific information. Such complicated handling creates cognitive load and impacts the users’ productivity. More specifically due to the complexity of the purpose of analytics products, to provide meaningful information (e.g. descriptives, predictions, prescriptions) at the right time, it must be considered that users’ journeys in analytics products fundamentally differ to the journeys of users of traditional e-commerce products. Whereas a common rule- or filtering based recommendation routine, or a chatbot, might be applicable to facilitate and enhance the overall User Experience (UX) of online shoppers, this might not suffice for analysts who are seeking to derive insights from data. We present preliminary results of an industry research study about the approach to combine natural language dialog- and content-flow based user interactions with content recommendations, in order to enhance UX of information retrieval from a data-driven analytics system. We demonstrate a prototype model towards a virtual assistant system that integrates predictions of the user’s intention which information to retrieve next with prescriptive analytics based on the context of the current and past conversations.Mirchev, C.; Metz, J.; Herrmann, M. (2020). Enhancing UX of analytics products with AI technology. Editorial Universitat Politècnica de València. 341-341. http://hdl.handle.net/10251/148778OCS34134

    Diagnosing Latent Tuberculosis Infection in the HIV Era

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    Tuberculin skin testing (TST) and Interferon-gamma (IFNγ)release assays (IGRAs) are presently the only available assays for the detection of Mycobacterium tuberculosis infected individuals. IGRAs might progressively replace TST, as numerous published reports establish their higher specificity and similar sensitivity when tested in BCG vaccinated, immunocompetent individuals or in populations who may have been in contact with atypical mycobacteria. However, few published reports have commented on their role in TB diagnosis in immunocompromised individuals (HIV, immunosuppressive therapy, cancer…). It is the purpose of this report to review IGRAs published studies in HIV individuals in endemic and non endemic area for tuberculosis (TB). IGRAs were tested in the presence or absence of active TB but correlated to duration of exposure. In newly diagnosed active TB, IGRAs demonstrated a similar sensitivity to TST. In TB non infected individuals, TST and IGRAs also gave similar values when categorization of individuals was correlated to the risk of infection. A higher number of positive IGRAs was observed in individuals from TB endemic areas, in similar proportions to immunocompetent individuals. Comparison between the two IGRAs: QuantiFERON-TB Gold® (QF-TB, Cellestis, Australia) and T-SPOT-TB® (Oxford Immunotec, UK), and against TST, in the same HIV population demonstrates a higher sensitivity of T-SPOT-TB and TST than QF-TB. Indeterminate results, which correspond to the absence of a positive T-cell IFNγ response towards phytohemaglutinin (PHA), is a key point when comparing both IGRAs. This PHA control is indicative of the level of immunosuppression observed in the tested individual. QF-TB seems to present, in HIV populations, more indeterminate results than T-SPOT-TB. The calibration and/or concentration of PBMC on nitrocellulose membrane for the T-SPOT-TB, as compared to a whole blood assay, might explain this difference, with less indeterminate results with the T-SPOT-TB assay. Neither assay is able to differentiate active TB from latent TB infection (LTBI). Several laboratories have tried new antigenic epitopes to solve this issue. It is of importance that these studies need to be repeated on a larger scale by others to validate their results. Two blood assays might add information characterising the evolution from LTBI to active TB: either by losing protective immunity, as demonstrated by the whole blood killing assay, or by evaluating the kinetics of the antibodies synthesized against M. tuberculosis specific antigens. In conclusion, longitudinal studies are still needed to validate IGRAs and other assays and to define their respective predictive values

    Communication audiovisuelle et peinture

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    Les médias audio-visuels s'intéressent, parfois, à l'art pictural en proposant, aux téléspectateurs la présentation de quelques tableaux. L'auteur cherche à savoir s'ils peuvent rendre compte de ceux-ci. Les conditions matérielles du passage du tableau à l'écran sont explicitées, le rapport au son dans l'audiovisuel également. Selon lui la télévision modifie complètement la perception de l’œuvre jusqu'à la rendre méconnaissable (effets de lumière, angle d'observation). L’œuvre picturale, unique, n'est parfois vue que grâce au média télévisuel : le fait qu'il la déforme gène l'auteur

    A CONSTANS-like gene candidate that could explain most of the genetic variation for flowering date in Medicago truncatula

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    Flowering is a critical period during a plant’s life cycle, and thus the identification and characterization of genes involved in flowering date control are of great importance in agronomy, breeding, population genetics and ecology. The model species Medicago truncatula can be used to detect genes explaining the variation for flowering date, which could also explain this variation in legume crops. The objective of this study was to identify the most promising candidate gene explaining a major quantitative trait locus (QTL) for flowering date previously found in three M. truncatula mapping populations. Fine mapping and bioinformatic analysis of bacterial artificial chromosomes (BACs) in the confidence interval of the QTL showed six genes potentially involved in the control of flowering date. Two of these genes, similar to CONSTANS and FT of Arabidopsis thaliana respectively, had genomic mutations when compared to the parents. The transcriptomic study of these genes by semi-quantitative RT-PCR in leaves and flowers sampled at two developmental stages showed that the CONSTANS-like gene was differentially expressed in the two parental lines. A gene belonging to the CONSTANS-like family could explain the major QTL for flowering date segregating in M. truncatula progenies

    Vector Mesons in Nuclear Medium

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    We summarize the current theoretical and experimental status of the spectral change of the vector mesons in dense matter.Comment: 4 pages, Latex, talk at Quark Matter '9

    Temporal Changes and Alternating Host Tree Root and Shoot Growth Affect Soil Microbiomes

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    Patterns of trees’ endogenous rhythmic growth (ERG) and paralleled C allocation shift between root and shoot systems have been studied, but there is still a need to understand their impact in shaping soil microbiomes. Moreover, the impact of plants on soil microbial communities can be modulated or overweighed by time-induced plant and/or seasonal changes. Thus, we intended to analyze the structure of soil microbiomes as response to simultaneous alternated host tree root and shoot flushes and time-induced changes within one vegetation period at two sites in Central Germany. In this study, we utilized oak phytometers (Quercus robur L., clone DF159) as host trees, and made use of their ERG, whereby consecutive root and shoot flushes make a complete growth cycle. We studied two complete growth cycles during the same vegetation period, performed a non-destructive soil sampling and applied high-throughput amplicon sequencing of the bacterial 16S gene and the fungal ITS2 region. As C allocation shifts between the tree root and shoot, released root exudates and consequently the nutrient availability alternate for soil microorganisms. We therefore anticipated different microbial communities in the host tree root zone along the growth cycles until autumnal leaf senescence. In our results, the bacterial community exhibited a directional change over time along the vegetation period. In contrast, the fungal community appeared sample specific. Our findings enlarge the current understanding of the temporal microbial assembly in the host tree root zone

    Preparation, Modification, and Evaluation of Cruentaren A and Analogues

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    An expeditious total synthesis of the highly cytotoxic F-ATPase inhibitor cruentaren A (1) is described based on a ring-closing alkyne metathesis (RCAM) reaction for the formation of the macrocylic ring. Other key transformations comprise a C-acylation of the benzyl lithium reagent derived from orsellinic acid ester 9 with Weinreb amide 7, a CBS reduction of the resulting ketone 10, and a Soderquist propargylation of aldehyde 21 with allenylborane (S)-27 to set the C-15 chiral center of the required alcohol fragment 25. The RCAM precursor 33 was assembled by acylation of 25 with acid fluoride 32, since more conventional methods for ester bond formation were unproductive. Moreover, the choice of the protecting groups, in particular for the secondary alcohol at C-9, which is prone to engage in translactonization, turned out to be critical; a relatively stable TBDPS ether had to be chosen for this site, which was removed in the final step of the synthesis with aqueous HF since other fluoride sources met with failure. The successful synthetic route was then expanded beyond the natural product, bringing a series of analogues into reach that feature incremental but deep-seated structural modifications. Three of these fully synthetic compounds turned out to be as or even more cytotoxic than cruentaren A itself against L-929 mouse fibroblast cells, reaching IC50 values as low as 0.7 ng mL−1
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