289 research outputs found

    Quantification and Identification of Road Organic Matter in an Absorbing Storm Basin, RN 20 Olivet-Orléans, France.

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    The deterioration of the quality of superficial and subsurface waters by motorway organic pollution is a problem of great concern nowadays. The absorption of road runoff waters through sinkhole clay filled in a karstic area has been proposed as a way to the attenuation pollution. The groundwaters near of surface are very vulnerable at this pollution. The study of the storm basin of Belle-Croix (RN 20 Loiret) indicates a diminution of DOC levels through the first meter of infiltration in sinkhole, and then little change occurs down 5 meters. However only the > 10 KD (10 nm) organic fraction is retained. This fraction is weakly fluorescent and should correspond to black carbon (BC) matter associated to clays as it is suggested by Electron Microscopy in Transmission EMT observation. The < 10 KD fraction which are the more fluorescent account for up to 80 % of total DOC at 5 meter depth, at the contact with the limestone

    Fibrosarcome du larynx - A propos d'un cas

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    Le fibrosarcome du larynx est une entitĂ© histologique rare, qui reprĂ©sente moins de 10% de tous les sarcomes des tissus mous, moins de 2 % des cancers laryngĂ©s. Cette localisation pose des problĂšmes diagnostique, thĂ©rapeutique et pronostique. Nous prĂ©sentons un cas de fibrosarcome laryngĂ© chez un patient de 54 ans. La confirmation histologique etimmunohistologique a Ă©tĂ© faite sur la piĂšce d’exĂ©rĂšse chirurgicale et surtout sur une confrontation anatomoclinique. La prise en charge thĂ©rapeutique est multidisciplinaire, associant la chirurgie qui doit ĂȘtre la plus complĂšte sans curage ganglionnaire et la radiothĂ©rapie. Le pronostic est gĂ©nĂ©ralement sĂ©vĂšre, dĂ©pend essentiellement de degrĂ© de diffĂ©renciation histologique.Mots clĂ©s : fibrosarcome ; larynx ; chirurgie ; radiothĂ©rapie

    Messinian salinity crisis impact on the groundwater quality in Kert aquifer NE Morocco: Hydrochemical and statistical approaches.

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    Groundwater's studies at middle Kert aquifer in northeast of Morocco are very important due to the semi-arid character and its geological history. The region is recognized by messinian salinity crisis already 5.6 Ma. Water chemistry is mainly dominated by dissolution of evaporate rocks (Halite and Gypsum) related to outcropping and basement limits developed in Messinian age. Freshwater with total dissolved solids 740 mg/l (average value) in Tafersite district is chemically distinct from saline water with total dissolved solids of 9803 mg/l in the south zone. In wadis, water is S04-Cl-Ca type; they are influenced by the surrounding highlands located at the south of the plain. The investigation reveals that weathering of evaporated rocks is the processes responsible for high Na+, Ca2+, Mg2+, Cl andSO42- concentrations. Also, hydro chemical data displays that freshwater observed in the northwest part reflect the influence of freshwaters coming from metamorphic massive of Temsamane. The factorial analysis reveal three sources of salinization, the principal one is described above, whilst the dissolution of carbonates and human influence represented by NO3- played only a secondary role

    Frequency-Domain Electromagnetic Mapping of an Abandoned Waste Disposal Site: A Case in Sardinia (Italy)

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    For decades, bad practices inmunicipal and industrial wastemanagement have had negative environmental impacts, generating high health risks for people and the environment. The use of badly designed, not engineered, and not well-operated landfills has, around the world, produced a large number of potentially contaminated sites, for which there are urgent needs to assess the actual risk and to proceed, in case, with reclamation activities. One of these sites, an abandoned waste disposal site located near a Site of Community Importance on the central-eastern coast of Sardinia (Italy), is the subject of the case history described in this work. As a part of a multi-method geophysical characterisation, a frequency-domain electromagnetic (FDEM) mapping survey was carried out with the specific aim of detecting the presence of buried materials (waste) and of delineating the lateral extent of the landfill by identifying the electrical conductivity anomalies produced, for the most part, by the conductive waste fill. Using an EM31 device in the vertical-dipole configuration, at a height of 0.9 m above the ground, both quadrature and in-phase electromagnetic responses were collected over a 7-hectare area with elevation varying between 6 m and 2.8 m above sea level. After removing the measurements identified as data coming from any recognisable surface man-made features within the survey area or near its perimeter, the filtered quadrature response (expressed as apparent conductivity) ranged from 5.5 mS/m to about 188.6 mS/m. All values are beyond the low induction number (LIN) condition and valid for the classical EM31 mapping, thus requiring advanced data processing. To obtain undistorted, meaningful, and interpretable high-resolution maps, measured data have been processed to correct the bias, introduced by the nonlinearity of the device, as a function of height above ground and the topography. The comparative analysis of the apparent conductivity map, obtained by the properly processed EM31 data and some aerial photos that clearly documented the site history, has allowed unequivocal delineation of the landfill extent, in good agreement with the results obtained with other geophysical methods (not described in this paper) and with the ground truthing data provided by three boreholes, which were core-drilled at the end of the study at three locations selected on the basis of the apparent conductivity map

    Reversible dilated cardiomyopathy caused by hypothyroidism

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    The association between lack of thyroid hormones and cardiac dysfunction has been well described. We report two new cases of patients with dilated cardiomyopathy (DCM), revealing a periphery hypothyroidism and for whom cardiac function significantly improved after L thyroxin substitutive treatment. Our cases highlight the necessity to perform thyroid function testing to investigate the etiology of non ischemic DCM

    Geoelectrical classification of Gypsum Rocks

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    Abstract Gypsum rocks are widely exploited in the world as industrial minerals. The purity of the gypsum rocks (percentage in gypsum mineral in the whole rock) is a critical factor to evaluate the potential exploitability of a gypsum deposit. It is considered than purities higher than 80% in gypsum are required to be economically profitable. Gypsum deposits have been studied with geoelectrical methods; a direct relationship between the electrical resistivity values of the gypsum rocks and its lithological composition has been established, with the presence of lutites being the main controlling factor in the geoelectrical response of the deposit. This phenomenon has been quantified in the present study, by means of a combination of theoretical calculations, laboratory measurements and field data acquisition. Direct modelling has been performed; the data have been inverted to obtain the mean electrical resistivity of the models. The laboratory measurements have been obtained from artificial gypsum-clay mixture pills, and the electrical resistivity has been measured using a simple electrical circuit with direct current power supply. Finally, electrical resistivity tomography data have been acquired in different evaporite Tertiary basins located in North East Spain; the selected gypsum deposits have different gypsum compositions. The geoelectrical response of gypsum rocks has been determined by comparing the resistivity values obtained from theoretical models, laboratory tests and field examples. A geoelectrical classification of gypsum rocks defining three types of gypsum rocks has been elaborated: (a) Pure Gypsum Rocks ([75% of gypsum content), (b)Transitional Gypsum Rocks (75 55%), and (c) Lutites and Gypsum-rich Lutites (\55%). From the economic point of view, the Pure Gypsum Rocks, displaying a resistivity value of [800 ohm.m, can be exploited as industrial rocks. The methodology used could be applied in other geoelectrical rock studies, given that this relationship between the resistive particles embedded within a conductive matrix depends on the connectivity of the matrix particles

    Effet des extraits de compost sur la croissance mycélienne et l'agressivité du Fusarium oxysporum f. sp. radicis-lycopersici

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    Effect of compost tea on mycelial growth and disease severity of Fusarium oxysporum f. sp. radicis-lycopersici. Simultaneous addition, on culture media, of Fusarium oxysporum f. sp. radicis-lycopersici and compost teas revealed that the latest induced the inhibition of the mycelial growth of the pathogen. This inhibition, noted after an incubation period of about six days at 25°C, was more important when compost teas were enriched in PDB (Potato Dextrose Broth), where it may reach 70% compared to the control. Transplantation of tomato seedlings, previously inoculated by a conidial suspension of F. oxysporum f. sp. radicis-lycopersici, in a container media (peat, perlite or the mixture of the two substrates) treated by compost teas has signifi cantly reduced Fusarium crown and root rot incidence compared to inoculated and untreated control seedlings. Disease incidence is more reduced when tomato inoculated plants are transplanted in peat treated by compost teas; indeed, these plants donʌt show any wilting and present a vigorous root system and a better vegetative growth

    Impacts and social implications of landuse-environment conflicts in a typical Mediterranean watershed

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    In coastal watersheds, services and landuse favour coastal tourism and urbanization, depriving rural upstream of infrastructure and attention. This unbalanced management leads to an intensification of socioeconomic changes that generate a structural heterogeneity of the landscape and a reduction in the livelihoods of the rural population. The incessant dissociation between the objectives of the stakeholders triggers landuse-environment-economy conflicts which threaten to mutate large-scale development programs. Here, we used multi-assessment techniques in a Mediterranean watershed from Morocco to evaluate the effects of landuse change on water, vegetation, and perception of the rural population towards environmental issues. We combined complementary vegetation indexes (NDVI and EVI) to study long-term landuse change and phenological statistical pixel-based trends. We assessed the exposure of rural households to the risk of groundwater pollution through a water analysis supplemented by the calculation of an Integrated Water Quality Index. Later, we contrasted the findings with the results of a social survey with a representative sample of 401 households from 7 villages. We found that rapid coastal linear urbanization has resulted in a 12-fold increase in construction over the past 35 years, to the detriment of natural spaces and the lack of equipment and means in rural areas upstream. We show that the worst water qualities are linked to the negative impact of anthropogenic activities on immediately accessible water points. We observe that rural households are aware of the existence and gravity of environmental issues but act confusedly because of their low education level which generates a weak capacity to understand cause and effect relationships. We anticipate the pressing need to improve the well-being and education of the population and synergistically correct management plans to target the watershed as a consolidated system. Broadly, stakeholders should restore lost territorial harmony and reallocate landuse according to a sustainable environment-socioeconomic vision

    Géométrie de l'aquifÚre du Haouz oriental et Tassaout amont, Maroc occidental: approche géophysique et hydrogéologique

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    The aim of the present study is to improve the knowledge of the geometry and hydrogeology of the eastern Haouz aquifer and part of the Upper Tassaout aquifer, using the analysis and interpretation of boreholes, gravimetric analysis, seismic reflection and piezometric data. The examination of the gravity data shows that the Bouguer anomaly map is affected by a regional gradient increasing from the southeast to northwest. This gradient was determined and subtracted from the original data, to provide a residual gravity map which shows clearly highlighted anomalies. These anomalies generally reflect outcrop areas of the basement and the variation in thickness of the sedimentary cover across the study area. The seismic reflection profile confirms the gravity results, and shows that the region is formed by a horst which corresponds to the exposed bedrock of Jebilets in the north of Haouz basin, and a subsidence area where coverage is widespread in the south of the plain of Haouz. In this area, the large thickness of the cover allows the accumulation of water and provides the recharge of the groundwater reservoir. The rise of the basement in the north of the Haouz basin imposes a dividing line of two groundwater flow direction

    Multi-view Brain Network Prediction from a Source View Using Sample Selection via CCA-Based Multi-kernel Connectomic Manifold Learning

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    Several challenges emerged from the dataclysm of neuroimaging datasets spanning both healthy and disordered brain spectrum. In particular, samples with missing data views (e.g., functional imaging modality) constitute a hurdle to conventional big data learning techniques which ideally would be trained using a maximum number of samples across all views. Existing works on predicting target data views from a source data view mainly used brain images such as predicting PET image from MRI image. However, to the best of our knowledge, predicting a set of target brain networks from a source network remains unexplored. To ll this gap, a multi-kernel manifold learning (MKML) framework is proposed to learn how to predict multi-view brain networks from a source network to impute missing views in a connectomic dataset. Prior to performing multiple kernel learning of multi-view data, it is typically assumed that the source and target data come from the same distribution. However, multi-view connectomic data can be drawn from different distributions. In order to build robust predictors for predicting target multi-view networks from a source network view, it is necessary to take into account the shift between the source and target domains. Hence, we first estimate a mapping function that transforms the source and the target domains into a shared space where their correlation is maximized using canonical correlation analysis (CCA). Next, we nest the projected training and testing source samples into a connectomic manifold using multiple kernel learning, where we identify the most similar training samples to the testing source network. Given a testing subject, we introduce a cross-domain trust score to assess the reliability of each selected training sample for the target prediction task. Our model outperformed both conventional MKML technique and the proposed CCA-based MKMLtechnique without enhancement by trust scores
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