Télévision interactive : analyse exploratoire de l’attitude des consommateurs envers cette nouvelle forme de média.

La télévision interactive, en particulier l’interactivité entre les téléspectateurs et les programmes télévisés, constitue l’une des formes les plus ambitieuses de communication entre le consommateur et un média. Cette recherche exploratoire a pour objet de découvrir les attitudes des consommateurs à l’égard de cette nouvelle forme de média. Alors que la littérature ne fait état que des attitudes positives des consommateurs envers les médias interactifs, les résultats obtenus sont plus partagés. Ils montrent que les attitudes négatives sont diverses et nombreuses : elles sont d’ordre émotionnel, exprimées par différentes peurs, et utilitaire, exprimées par une non-considération du média. Les attitudes positives sont d’ordre cognitif, affectif et conatif : la télévision interactive est considérée comme intelligente, éducative, anti-passive et accompagnatrice.Interactive television, in particular interactivity between TV viewers and TV programs, appears as one of the most ambitious ways of communication between the consumer and a media. This exploratory research aims to discover consumers’ attitude toward this new form of media. Whereas the literature only mentions positive attitudes of consumers toward interactive media, results are more divided. They show that negative attitudes are various and numerous : they are emotional oriented, expressed by different fears, and utilitarian oriented, expressed like a gimmick. The positive attitudes are cognitive, affective and behavioral : interactive television is considered as intelligent, educative, anti-passive andenriched TV; interactive television; interactivity; attitude; télévision enrichie; télévision interactive; interactivité;

Spillover and diffraction sidelobe contamination in a double-shielded experiment for mapping Galactic synchrotron emission

We have analyzed observations from a radioastronomical experiment to survey the sky at decimetric wavelengths along with feed pattern measurements in order to account for the level of ground contamination entering the sidelobes. A major asset of the experiment is the use of a wire mesh fence around the rim-halo shielded antenna with the purpose of levelling out and reducing this source of stray radiation for zenith-centered 1-rpm circular scans. We investigate the shielding performance of the experiment by means of a geometric diffraction model in order to predict the level of the spillover and diffraction sidelobes in the direction of the ground. Using 408 MHz and 1465 MHz feed measurements, the model shows how a weakly-diffracting and unshielded antenna configuration becomes strongly-diffracting and double-shielded as far-field diffraction effects give way to near-field ones. Due to the asymmetric response of the feeds, the orientation of their radiation fields with respect to the secondary must be known a priori before comparing model predictions with observational data. By adjusting the attenuation coefficient of the wire mesh the model is able to reproduce the amount of differential ground pick-up observed during test measurements at 1465 MHz.Comment: 14 pages, 17 eps + 1 gif figures and 4 Tables. Accepted for publication in A&AS. Fig.7 available at full resolution from http://www.das.inpe.br/~tello/publications.ht

Développement et caractérisation d'un procédé de fabrication de composites et biocomposites à base de nanoparticules d'argile et de résine polyester insaturée destinés à l'industrie du transport.

RÉSUMÉ Depuis les dix dernières années, l’ajout de nanoparticules dans la fabrication de pièces en matériaux composites provoque un intérêt croissant grâce aux nombreuses améliorations des propriétés observées une fois combinées à une matrice polymère et à un renfort fibreux. Bien que récente, cette technologie est en plein développement et est promise à un brillant avenir. L’attrait principal des nanoparticules est que celles-ci n’agissent pas seulement comme des additifs conventionnels, mais aussi comme un renfort qui apporte une contribution importante au niveau des propriétés générales des matériaux composites. L’obtention de telles propriétés, une bonne compréhension de l’interaction entre les nanoparticules et le polymère est essentielle. Ce projet de maîtrise a pour objectif le développement d’un matériau composite aux propriétés améliorées par l’addition de nanoparticules d’argile dans une matrice de résine polyester insaturée. L’étude vise l’optimisation des propriétés mécaniques de la pièce ainsi que de ses propriétés ignifuges grâce aux nanoargiles et ces améliorations sont de première importance pour l’industrie du transport. Le premier défi a été la dispersion des nanoparticules d’argiles dans une matrice afin d’obtenir une structure homogène sans agglomérats. En effet, ces derniers agissent en tant que concentrateurs de contraintes qui pourraient fragiliser la pièce. Trois différentes techniques de mélange ont été expérimentées dont la sonication, le mélange à haut cisaillement (HSM) et le mélange manuel. Dépendamment du choix de la technique de dispersion, différentes structures peuvent être obtenues, l’idéal étant une exfoliation des nanoparticules. De plus, cette dispersion dépend grandement de la compatibilité nanoargile-polymère ainsi que du choix de la technique de dispersion. Des études rhéologiques ont été accomplies afin de caractériser la structure interne des nanocomposites obtenus. Dans un premier temps, des mesures en cisaillement simple ont illustré une augmentation de la viscosité de l’ordre de 3 décades. De plus, un fort comportement non-Newtonien rhéofluidifiant est observé pour le mélange obtenu par HSM après l’addition et la dispersion des nanoparticules. Ce comportement se définit par une structure initiale désorganisée des feuillets et est dû à la baisse de la mobilité des chaînes polymères. Des mesures en mode oscillatoire à faible amplitude dans le domaine linéaire ont illustré un comportement de type « gel faible » pour les mélanges HSM. Cet état est régit par de fortes interactions entre les nanoargiles et la matrice indiquant une probable exfoliation des----------ABSTRACT For the ten last years, the addition of nanoparticles in the manufacturing process of composite material has a growing interest due to the enhancement of many properties obtained once they are combined to a polymeric matrix and a fibrous reinforcement. Although this technology is recent, it has a brilliant future ahead. Nanoparticles are not just usual additives, they also act as a reinforcement that makes an important contribution to the composite performance and in order achieve those improvements, a good understanding of the interaction between nanoparticles and the polymer is essential. The purpose of this project is to develop a composite with improved properties by the addition of clay nanoparticles in the unsaturated resin polyester matrix. This study seeks the general improvement of composite mechanical properties as well as its fireproof properties with the addition of nanoclays. This aspect would be most useful for the transport’s industry. The first challenge was the dispersion of nanoclays in a polymeric matrix to obtain a homogeneous structure without agglomerates. Three techniques were compared: manual mixing, sonication and high shear mixing (HSM). Various structures can be obtained depending on the dispersion technique, the ideal being exfoliation, i.e. a homogenized distribution of polymer between silicate nano-layers in order to increase matrix properties. This dispersion mainly depends on compatibility between clay and polymer. Rheological studies were accomplished in order to characterize the internal structure of manufactured nanocomposites. First, simple shear measurements showed an increase in viscosity of about 3 decades for HSM blends. Moreover, strong non-Newtonian behavior was observed for the HSM mixtures after the addition of nanoparticles and dispersion into the unsaturated polyester matrix. This behavior is defined by an initially disorganized structure of clay layers due to the decrease of polymer chains mobility. Later on, small amplitude oscillatory shear measurements in the linear viscoelastic zone illustrated a solid-like behavior for HSM mixtures. This state is governed by strong interactions between the nanoclay particles and the polymer indicating a probably exfoliated structure. The scanning electron microscopy images showed a reduction of the agglomerate’s size for the type of dispersion compared to manual mixing and sonication

A Study of Nanoclay Reinforcement of Biocomposites Made by Liquid Composite Molding

Liquid composite molding (LCM) processes are widely used to manufacture composite parts for the automotive industry. An appropriate selection of the materials and proper optimization of the manufacturing parameters are keys to produce parts with improved mechanical properties. This paper reports on a study of biobased composites reinforced with nanoclay particles. A soy-based unsaturated polyester resin was used as synthetic matrix, and glass and flax fiber fabrics were used as reinforcement. This paper aims to improve mechanical and flammability properties of reinforced composites by introducing nanoclay particles in the unsaturated polyester resin. Four different mixing techniques were investigated to improve the dispersion of nanoclay particles in the bioresin in order to obtain intercalated or exfoliated structures. An experimental study was carried out to define the adequate parameter combinations between vacuum pressure, filling time, and resin viscosity. Two manufacturing methods were investigated and compared: RTM and SCRIMP. Mechanical properties, such as flexural modulus and ultimate strength, were evaluated and compared for conventional glass fiber composites (GFC) and flax fiber biocomposites (GFBiores-C). Finally, smoke density analysis was performed to demonstrate the effects and advantages of using an environment-friendly resin combined with nanoclay particles

(S)norlaudanosoline synthase. the first enzyme in the benzylisoquinoline biosynthetic pathway

1. introduction Isoquinoline alkaloids form the largest group of alkaloids in the plant kingdom. Numerous publications deal with aspects of the biosynthesis of these compounds in vivo [ 11, while isoquinoline biosynthesis at the cell-free level had hardly been touched [Z]. The initial reaction in isoquinoline biosynthesis has long [3] been assumed to be a condensation of two aromatic units, both derived from tyrosine, namely dopamine and 3,4-d~ydroxyphenylacet~dehyde [4]. This scheme was later modified [5] where it was reported that condensation of dopamine with 3,4-dihydroxyphenylpyruvate would lead to an amino acid, norlaudanosoline-l-carboxylic acid, which in turn, by decarboxylation, would yield norlaudanosoline

A radio continuum survey of the southern sky at 1420 MHz. Observations and data reduction

We describe the equipment, observational method and reduction procedure of an absolutely calibrated radio continuum survey of the South Celestial Hemisphere at a frequency of 1420 MHz. These observations cover the area 0h < R.A. < 24h for declinations less than -10 degree. The sensitivity is about 50 mK T_B (full beam brightness) and the angular resolution (HPBW) is 35.4', which matches the existing northern sky survey at the same frequency.Comment: 9 pages with 9 figures, A&A, in pres

Autoantibody Profiling for Lung Cancer Screening Longitudinal Retrospective Analysis of CT Screening Cohorts

Recommendations for lung cancer screening present a tangible opportunity to integrate predictive blood-based assays with radiographic imaging. This study compares performance of autoantibody markers from prior discovery in sample cohorts from two CT screening trials. One-hundred eighty non-cancer and 6 prevalence and 44 incidence cancer cases detected in the Mayo Lung Screening Trial were tested using a panel of six autoantibody markers to define a normal range and assign cutoff values for class prediction. A cutoff for minimal specificity and best achievable sensitivity were applied to 256 samples drawn annually for three years from 95 participants in the Kentucky Lung Screening Trial. Data revealed a discrepancy in quantile distribution between the two apparently comparable sample sets, which skewed the assay’s dynamic range towards specificity. This cutoff offered 43% specificity (102/237) in the control group and accurately classified 11/19 lung cancer samples (58%), which included 4/5 cancers at time of radiographic detection (80%), and 50% of occult cancers up to five years prior to diagnosis. An apparent ceiling in assay sensitivity is likely to limit the utility of this assay in a conventional screening paradigm. Pre-analytical bias introduced by sample age, handling or storage remains a practical concern during development, validation and implementation of autoantibody assays. This report does not draw conclusions about other logical applications for autoantibody profiling in lung cancer diagnosis and management, nor its potential when combined with other biomarkers that might improve overall predictive accuracy

Photobiomodulation therapy in management of cancer therapy-induced side effects : WALT position paper 2022

DisclaimerThis article is based on recommendations from the 12(th) WALT Congress, Nice, October 3-6, 2018, and a follow-up review of the existing data and the clinical observations of an international multidisciplinary panel of clinicians and researchers with expertise in the area of supportive care in cancer and/or PBM clinical application and dosimetry. This article is informational in nature. As with all clinical materials, this paper should be used with a clear understanding that continued research and practice could result in new insights and recommendations. The review reflects the collective opinion and, as such, does not necessarily represent the opinion of any individual author. In no event shall the authors be liable for any decision made or action taken in reliance on the proposed protocols. Objective: This position paper reviews the potential prophylactic and therapeutic effects of photobiomodulation (PBM) on side effects of cancer therapy, including chemotherapy (CT), radiation therapy (RT), and hematopoietic stem cell transplantation (HSCT). Background: There is a considerable body of evidence supporting the efficacy of PBM for preventing oral mucositis (OM) in patients undergoing RT for head and neck cancer (HNC), CT, or HSCT. This could enhance patients' quality of life, adherence to the prescribed cancer therapy, and treatment outcomes while reducing the cost of cancer care. Methods: A literature review on PBM effectiveness and dosimetry considerations for managing certain complications of cancer therapy were conducted. A systematic review was conducted when numerous randomized controlled trials were available. Results were presented and discussed at an international consensus meeting at the World Association of photobiomoduLation Therapy (WALT) meeting in 2018 that included world expert oncologists, radiation oncologists, oral oncologists, and oral medicine professionals, physicists, engineers, and oncology researchers. The potential mechanism of action of PBM and evidence of PBM efficacy through reported outcomes for individual indications were assessed. Results: There is a large body of evidence demonstrating the efficacy of PBM for preventing OM in certain cancer patient populations, as recently outlined by the Multinational Association for Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO). Building on these, the WALT group outlines evidence and prescribed PBM treatment parameters for prophylactic and therapeutic use in supportive care for radiodermatitis, dysphagia, xerostomia, dysgeusia, trismus, mucosal and bone necrosis, lymphedema, hand-foot syndrome, alopecia, oral and dermatologic chronic graft-versus-host disease, voice/speech alterations, peripheral neuropathy, and late fibrosis amongst cancer survivors. Conclusions: There is robust evidence for using PBM to prevent and treat a broad range of complications in cancer care. Specific clinical practice guidelines or evidence-based expert consensus recommendations are provided. These recommendations are aimed at improving the clinical utilization of PBM therapy in supportive cancer care and promoting research in this field. It is anticipated these guidelines will be revised periodically.Peer reviewe