751 research outputs found

    Diffusion Of Indigo Molecules Inside The Palygorskite Clay Channels

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    The search for durable dyes led several past civilizations to develop artificial pigments. Maya Blue (MB), manufactured in pre-Columbian Mesoamerica, is one of the best known examples of an organic-inorganic hybrid material. Its durability is due to the unique association of indigo molecule and palygorskite, a particular fibrous clay occurring in Yucatan. Despite 50 years of sustained interest, the microscopic structure of MB and its relation to the durability remain open questions. Combining new thermogravimetric and synchrotron X-ray diffraction analyses, we show that indigo molecules can diffuse into the channel of the palygorskite during the heating process, replacing zeolitic water and stabilizing the room temperature phases of the clay

    Environmental impact for offshore wind farms: Geolocalized Life Cycle Assessment (LCA) approach

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    International audienceThis paper presents an approach for Environmental Impact Assessment through the use of geolocalized LCA approach, for fixed and floating offshore wind farms. This work was undertaken within the EU-sponsored EnerGEO project, aiming at providing a versatile modeling platform for stakeholders allowing calculation, forecasting and monitoring of environmental impacts of different sources of energy. This paper described the geolocalized LCA approach, and its use for the evaluation of environmental impacts of wind energy. The effects of offshore wind farms on global environnemental impacts are evaluated though the LCA approach. It takes into account the type of wind farm, the construction phase, all technical aspects, the operation and maintenance scheme and the decommissioning. It also includes geolocalized information such as wind resources, bathymetry, accessibility ... Environmental impact parameters are accessible through a web service helping the decision makers in assessing the environnemental impacts

    Web tool for energy policy decision-making through geo-localized LCA models: A focus on offshore wind farms in Northern Europe

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    International audienceEnvironmental performances of electricity generation, expressed as environmental impacts per kWh of electricity produced, depend strongly on technical, methodological and geographical parameters. When considering the global environmental performances of renewable energies, a geo-dependent life cycle assessment (LCA) taking into account geographical issues is of high interest. To illustrate this issue, a web map service enabling "geolocalized life cycle assessment" of offshore wind farms for different configurations has been developed. Based on a modular LCA model and on collaborative works made within the framework of the FP7 co-funded project EnerGEO, the developed tool should help decision makers in assessing the global environmental impacts caused by an offshore wind farm in Northern Europe

    Environmental data for the planning of off-shore wind parks from the EnerGEO Platform of Integrated Assessment (PIA)

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    International audienceThe EU-sponsored EnerGEO project aims at providing decision makers with a modelling platform to assess the environmental impacts of different sources of renewable energy. One of the pillars of the project is the Wind Energy Pilot, addressing the effects of offshore wind parks on air pollution and energy use. The methods used in the pilot and the underlying environmental databases are integrated into a WebGIS client tool and made available to the public. This paper is dedicated to describing the environmental databases and supporting data incorporated in the client tool. A 27-km resolution, 11-year wind database is created using the WRF model. The wind database is used to assess the wind climate in the north-west Atlantic region and to derive the potential power output from offshore wind parks. Auxiliary data concerning water depth, distance to shore and distance to the nearest suitable port are created to aid the planning and maintenance phases. Seasonal workability conditions are assessed using a 20-year wave database. The distance at which future wind parks should be placed to exhibit different wind climates is investigated

    Grey matter atrophy in prodromal stage of dementia with Lewy bodies and Alzheimer’s disease

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    BACKGROUND: Little is known about the patterns of brain atrophy in prodromal dementia with Lewy bodies (pro-DLB). METHODS: In this study, we used SPM8 with diffeomorphic anatomical registration through exponentiated lie algebra to measure grey matter (GM) volume and investigate patterns of GM atrophy in pro-DLB (n = 28) and prodromal Alzheimer's disease (pro-AD) (n = 27) and compared and contrasted them with those in elderly control subjects (n = 33) (P ≤ 0.05 corrected for family-wise error). RESULTS: Patients with pro-DLB showed diminished GM volumes of bilateral insulae and right anterior cingulate cortex compared with control subjects. Comparison of GM volume between patients with pro-AD and control subjects showed a more extensive pattern, with volume reductions in temporal (hippocampi and superior and middle gyri), parietal and frontal structures in the former. Direct comparison of prodromal groups suggested that more atrophy was evident in the parietal lobes of patients with pro-AD than patients with pro-DLB. In patients with pro-DLB, we found that visual hallucinations were associated with relative atrophy of the left cuneus. CONCLUSIONS: Atrophy in pro-DLB involves the insulae and anterior cingulate cortex, regions rich in von Economo neurons, which we speculate may contribute to the early clinical phenotype of pro-DLB.This study was funded by Appel à Projet Interne (API) of the University Hospital of Strasbourg, Alsace Alzheimer 67, Fondation Université de Strasbourg and famille Jean Amrhein, and Projet Hospitalier de Recherche Clinique (PHRC) inter-régional (IDRCB 2012-A00992-41). The work was also supported by the following: the Newcastle Healthcare Charity (BH0070250); Academy of Medical Sciences, Wellcome Trust Starter Grants scheme for Clinical Lecturers (BH090112 to JPT); Wellcome Intermediate Clinical Fellowship (BH083281 to JPT); National Institute for Health Research (NIHR) Newcastle Biomedical Research Centre in Ageing and Chronic Disease and Biomedical Research Unit in Lewy Body Dementia, based at Newcastle upon Tyne Hospitals NHS Foundation Trust and Newcastle University; NIHR Dementia Biomedical Research Unit at Cambridge University Hospitals NHS Foundation Trust and the University of Cambridge

    Association of indigo with zeolites for improved colour stabilization

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    International audienceThe durability of an organic colour and its resistance against external chemical agents and exposure to light can be significantly enhanced by hybridizing the natural dye with a mineral. In search for stable natural pigments, the present work focuses on the association of indigo blue with several zeolitic matrices (LTA zeolite, mordenite, MFI zeolite). The manufacturing of the hybrid pigment is tested under varying oxidising conditions, using Raman and UV-visible spectrometric techniques. Blending indigo with MFI is shown to yield the most stable composite in all of our artificial indigo pigments. In absence of defects and substituted cations such as aluminum in the framework of the MFI zeolite matrix, we show that matching the pore size with the dimensions of the guest indigo molecule is the key factor. The evidence for the high colour stability of indigo@MFI opens a new path for modeling the stability of indigo in various alumino-silicate substrates such as in the historical Maya Blue pigment

    A Short-Term Physical Activity Randomized Trial in the Lower Mississippi Delta

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    Background: The purpose of this study was to determine if a short-term pedometer-based intervention results in immediate increases in time spent in moderate-to-vigorous physical activity (MVPA) compared to a minimal educational intervention. Methods: A sample of 43 overweight adults 35 to 64 years of age participated in a one week pedometer-based feasibility trial monitored by accelerometry. Participants were randomized into a one-week education-only group or a group that also wore a pedometer. Accelerometer-measured MVPA was measured over 7 days at baseline and again for 7 days immediately post-intervention. Results: Minutes of MVPA increased significantly in the overall sample (p = 0.02); however, the effect of adding the pedometer to the education program was not significant (p = 0.89). Mean (6SE) MVPA increased from 12.762.4 min/day to 16.263.6 min/day in the education-only group and from 13.263.3 min/day to 16.363.9 min/day in the education+pedometer group. The correlation between change in steps/day and change in MVPA was 0.69 (p,0.0001). Conclusions: The results of this study suggest that the addition of a pedometer to a short-term education program doe

    Vers une amélioration de la détection des chaleurs dans les troupeaux bovins grâce à une nouvelle méthode de diagnostic et de conseil (DetŒstrus)

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    La détection des chaleurs est une étape clé de la mise à la reproduction dans les troupeaux pratiquant l'insémination animale (IA). La qualité de la détection est difficile à évaluer rendant délicat le conseil dans ce domaine. "DetŒstrus" est une nouvelle méthode de diagnostic et de conseil centrée sur la détection des chaleurs et utilisable par les conseillers dans les troupeaux bovins où l'IA est pratiquée. L'objectif de ce document est de présenter cette méthode et sa première évaluation sur le terrain. Cette méthode est innovante dans la mesure où elle permet de distinguer les problèmes liés à la vache (défaut de cyclicité post-partum, de niveau d'expression des chaleurs) de ceux liés aux pratiques de l'éleveur (défaut de sensibilité, de spécificité de la détection), et ainsi de proposer des solutions ciblées et adaptées aux contraintes et objectifs de l'éleveur. La méthode se présente sous la forme d'un document Excel® organisé en fiches qui servent de support lors de l'audit et se décline en deux versions (laitière et allaitante). La version laitière comprend une estimation de la sensibilité et de la spécificité de la détection grâce à des équations de prédiction utilisant des données facilement accessibles en exploitation et prenant en compte le niveau d'expression des chaleurs des vaches. La version allaitante comprend un simulateur permettant d'estimer la reprise de cyclicité post-partum dans le troupeau, et donc de planifier la surveillance des chaleurs pour une utilisation facilitée de l'IA. Un premier test en exploitation de la méthode montre que 89% des conseillers (40/45) et la totalité des éleveurs (24/24) ont jugé l'audit satisfaisant. 91% des éleveurs (21/23) se sentent "mieux armés" sur la détection des chaleurs après l'audit. La durée totale de l'audit (préparation et intervention) a été de 3h ± 1h en troupeaux laitiers et 2h10 ± 42min en troupeaux allaitants. Les retours de l'essai ont permis d'optimiser la méthode prochainement disponible en téléchargement gratuit sur le site de l'Institut de l'Elevage
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