4,558 research outputs found

    Method of Solubilizing Carbon Nanotubes in Organic Solutions

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    Carbon nanotubes are dissolved in organic solutions by attaching an aliphatic carbon chain (which may contain aromatic residues) so as to render the carbon nanotubes soluble

    Effect of gentle stroking and vocalization on behaviour, mucosal immunity and upper respiratory disease in anxious shelter cats

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    Emotional, behavioural, and health benefits of gentle stroking and vocalizations, otherwise known as gentling, have been documented for several species, but little is known about the effect of gentling on cats in stressful situations. In this study, 139 cats rated as anxious upon admission to an animal shelter were allocated to either a Gentled or Control group. Cats were gentled four times daily for 10min over a period of 10 days, with the aid of a tool for cats that were too aggressive to handle. The cats' mood, or persistent emotional state, was rated daily for 10 d as Anxious, Frustrated or Content. Gentled cats were less likely to have negatively valenced moods (Anxious or Frustrated) than Control cats (Incidence Rate Ratio [IRR]=0.61 CI 0.42-0.88, P=0.007). Total secretory immunoglobulin A (S-IgA) was quantified from faeces by enzyme-linked immunosorbent assay. Gentled cats had increased S-IgA (6.9±0.7logμg/g) compared to Control cats (5.9±0.5logμg/g) (

    Method of Solubilizing Unshortened Carbon Nanotubes in Organic Solutions

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    Naked carbon nanotubes are dissolved in organic solutions by terminating the nanotubes with carboxylic acid groups and attaching an aliphatic carbon chain so as to render the carbon nanotubes soluble

    Reliable flow cytometric estimation of nuclear DNA content in coffee trees

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    La cytométrie en flux a permis d'obtenir des mesures précises de la taille des génomes de deux taxons (#C. liberica dewevrei et #C. pseudozanguebariae). L'iodure de propidium (IP) et le #Petunia hybrida ont été utilisés, respectivement, comme fluorochrome et standard interne. La linéarité de la relation entre la quantité d'ADN et le signal fluorescent digitalisé a été vérifiée. Cinq résultats majeurs ressortent : des conditions expérimentales optimales ont été définies pour l'estimation de la position des pics (moyenne et mode), le temps de coloration (au moins deux minutes), le voltage du photomultiplicateur (557 V) et de la concentration en IP (330 microg/ml) ; les effets du voltage et de la concentration en IP ont été paramétrés ; deux biais dus aux variations de voltage et de concentration en IP ont été décelés dans l'estimation de la quantité d'ADN par noyau. Ces biais ont été minimisés ; les tailles de génome de #C. liberica dewevrei et de #C. pseudozanguebariae$ ont été estimées avec précision (respectivement 2C = 1,421 plus ou moins 0,005 pg et 2C = 1,129 plus ou moins 0,005 pg) ; des variations entre génotypes ont été mises en évidence dans chaque taxon. (Résumé d'auteur

    Prehistoric exploitation of minerals resources. Experimentation and use-wear analysis of grooved stone tools from Grotta della Monaca (Calabria, Italy)

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    The Calabria region of Southern Italy is rich in mineralisation. Unfortunately, no consistent data are available about mineral exploitation in the later prehistoric periods. The Grotta della Monaca mine in Calabria is a prehistoric site that is characterised by the mineralisation of iron ores (such as goethite) and copper carbonates (malachite and azurite). For this reason, the site provides an exceptional opportunity to study a prehistoric mine in which several minerals were exploited during the late Neolithic and early Chalcolithic. In this study, we present the results of an experimental protocol and use-wear analysis conducted using macro-lithic tool replicas to extract mineral resources. The experimental test aimed at reconstructing the function of grooved stone tools found at Grotta della Monaca. Use-wear observation, through a combined low- and high-power approach on experimental and archaeological objects, allowed us to define different extraction techniques and methods of mineral treatments. These data enhance our understanding and reconstruction of the chaîne opératoires, economic choices, and cultural aspects that characterised prehistoric miners in Southern Italy

    Time-energy correlations in solar flare occurrence

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    The existence of time-energy correlations in flare occurrence is still an open and much debated problem. This study addresses the question whether statistically significant correlations are present between energies of successive flares as well as energies and waiting times. We analyze the GOES catalog with a statistical approach based on the comparison of the real catalog with a reshuffled one where energies are decorrelated. This analysis reduces the effect of background activity and is able to reveal the role of obscuration. We show the existence of non-trivial correlations between waiting times and energies, as well as between energies of subsequent flares. More precisely, we find that flares close in time tend to have the second event with large energy. Moreover, after large flares the flaring rate significantly increases, together with the probability of other large flares. Results suggest that correlations between energies and waiting times are a physical property and not an effect of obscuration. These findings could give important information on the mechanisms for energy storage and release in the solar corona

    From point cloud to BIM: a survey of existing approaches

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    International audienceIn order to handle more efficiently projects of restoration, documentation and maintenance of historical buildings, it is essentialto rely on a 3D enriched model for the building. Today, the concept of Building Information Modelling (BIM) is widely adoptedfor the semantization of digital mockups and few research focused on the value of this concept in the field of cultural heritage.In addition historical buildings are already built, so it is necessary to develop a performing approach, based on a first step ofbuilding survey, to develop a semantically enriched digital model. For these reasons, this paper focuses on this chain startingwith a point cloud and leading to the well-structured final BIM; and proposes an analysis and a survey of existing approacheson the topics of: acquisition, segmentation and BIM creation. It also, presents a critical analysis on the application of this chainin the field of cultural heritag

    Variations in the total nuclear DNA content in African Coffea species (Rubiaceae)

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    La quantité d'ADN totale par noyau a été estimée pour soixante-quinze génotypes de #Coffea appartenant à seize espèces diploïdes (2n=22) et #C. arabica (tétraploïde 2n=44) par cytofluorométrie en flux. L'agent fluorochrome utilisé est l'iodure de propidium (intercalent). La valeur 2C du génome des caféiers varie de 0,9 pg d'ADN par noyau à 1,9 pg. Trois espèces, originaires d'Afrique de l'Est (#C. sessiliflora, C. racemosa et #C. pseudozanguebariae) ont le plus petit génome (environ 1 pg par noyau). A l'opposé, trois espèces de forêt tropicale humide (#C. humilis, C. sp. Moloundou et #C. liberica) correspondent aux valeurs les plus élevées (1,6 pg). L'espèce tétraploïde #C. arabica$, originaire d'Ethiopie, a un génome de 2,5 pg. Au sein des espèces diploïdes, on note une importante variation des valeurs 2C pouvant atteindre 25 % pour une espèce. Les résultats sont comparés aux données analogues chez d'autres Angiospermes et une tentative d'interprétation des variations observées est présentée. (Résumé d'auteur

    End-to-End Evaluation in Simultaneous Translation

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    This paper presents the end-to-end evaluation of an automatic simultaneous translation system, built with state-of-the-art components. It shows whether, and for which situations, such a system might be advantageous when compared to a human interpreter. Using speeches in English translated into Spanish, we resent the evaluation procedure and we discuss the results both for the recognition and translation components as well as for the overall system. Even if the translation process remains the Achilles’ heel of the system, the results show that the system can keep at least half of the information, becoming potentially useful for final users

    Terminal-repeat retrotransposons with GAG domain in plant genomes : a new testimony on the complex world of transposable elements

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    A novel structure of nonautonomous long terminal repeat (LTR) retrotransposons called terminal repeat with GAG domain (TR-GAG) has been described in plants, both in monocotyledonous, dicotyledonous and basal angiosperm genomes. TR-GAGs are relatively short elements in length (<4 kb) showing the typical features of LTR-retrotransposons. However, they carry only one open reading frame coding for the GAG precursor protein involved for instance in transposition, the assembly, and the packaging of the element into the virus-like particle. GAG precursors show similarities with both Copia and Gypsy GAG proteins, suggesting evolutionary relationships of TR-GAG elements with both families. Despite the lack of the enzymatic machinery required for their mobility, strong evidences suggest that TR-GAGs are still active. TR-GAGs represent ubiquitous nonautonomous structures that could be involved in the molecular diversities of plant genomes
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