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Noujeim E.,National Council for Scientific Research CNRS | Khater C.,National Council for Scientific Research CNRS | Pages S.,French National Institute for Agricultural Research | Pages S.,Montpellier University | And 7 more authors.
Journal of Invertebrate Pathology | Year: 2011

A survey of entomopathogenic nematodes in Lebanon was conducted for the first time during 2008-2009. Samples were collected on the coastal strip and in nine vegetation types extending from the coastal line to 3088. m above sea level. Wooded and herbaceous ecosystems were considered for sampling purposes. A total of 570 samples were taken, out of which 1% were positive for entomopathogenic nematodes. Approximately, 15.8% out of the 19 sites sampled revealed entomopathogenic nematodes presence (representing three samples). Two entomopathogenic nematodes species Heterorhabditis bacteriophora and Steinernema feltiae were recovered, and identification of their symbiotic bacteria revealed the presence of a Xenorhabdus bovienii, Photorhabdus temperata subsp. thracensis, Photorhabdus luminescens subsp. kayaii and Photorhabdus luminescens subsp. Laumondii. © 2011 Elsevier Inc.


Mansour M.,Beirut Arab University | Roumie M.,National Council for Scientific Research CNRS | Samad B.A.,Jean Monnet University | Basma H.,Beirut Arab University | Korek M.,Beirut Arab University
Journal of Physics: Conference Series | Year: 2014

Magnetic materials such as yttrium iron garnet (YIG or Y3Fe5O12) present a great importance for their magneto-optic properties. They are potential materials used for applications in the domain of optical telecommunications for example. In this work, we have investigated YIG thin films deposited on substrates of quartz and GGG (gadolinium gallium garnet or Gd3Ga5O12). Using Rutherford backscattering spectrometry (RBS) we characterized the performed layers (thickness and stoichiometry) in order to correlate the films preparation conditions with the quality of the final material. We determined the optimal energy of the alpha particles beam used for RBS measurements and we fitted the experimental spectra using the SIMNRA simulated code. Our RBS results showed that the films have a stoichiometry close to that of the starting material. In addition, we found that the film thickness is proportional to deposition time but inversely proportional to the substrate temperature. Moreover, using x-ray diffraction (XRD) we determined the annealing effect on the structure of the profile of our thin films.


El Samad O.,Lebanese Atomic Energy Commission | Aoun M.,Lebanese Atomic Energy Commission | Nsouli B.,Lebanese Atomic Energy Commission | Khalaf G.,Marine Research Center | Hamze M.,National Council for Scientific Research CNRS
Journal of Environmental Radioactivity | Year: 2014

This investigation was carried out in order to assess the marine environmental radioactive pollution and the radiological impact caused by a large production plant of phosphate fertilizer, located in the Lebanese coastal zone. Natural radionuclides (238U, 235U, 232Th, 226Ra, 210Po, 210Pb, 40K) and anthropogenic 137Cs were measured by alpha and gamma spectrometry in seawater, sediment, biota and coastal soil samples collected from the area impacted by this industry. The limited environmental monitoring program within 2km of the plant indicates localized contamination with radionuclides of the uranium decay chain mainly due to the transport, the storage of raw materials and the free release of phosphogypsum waste. © 2013 Elsevier Ltd.


PubMed | Lebanese Atomic Energy Commission, National Council for Scientific Research CNRS and Marine Research Center
Type: | Journal: Journal of environmental radioactivity | Year: 2014

This investigation was carried out in order to assess the marine environmental radioactive pollution and the radiological impact caused by a large production plant of phosphate fertilizer, located in the Lebanese coastal zone. Natural radionuclides ((238)U, (235)U, (232)Th, (226)Ra, (210)Po, (210)Pb, (40)K) and anthropogenic (137)Cs were measured by alpha and gamma spectrometry in seawater, sediment, biota and coastal soil samples collected from the area impacted by this industry. The limited environmental monitoring program within 2km of the plant indicates localized contamination with radionuclides of the uranium decay chain mainly due to the transport, the storage of raw materials and the free release of phosphogypsum waste.


Kouzayha A.,National Council for Scientific Research CNRS | Al Iskandarani M.,National Council for Scientific Research CNRS | Mokh S.,National Council for Scientific Research CNRS | Rabaa A.R.,Lebanese University | And 3 more authors.
Journal of Agricultural and Food Chemistry | Year: 2011

A fast and reliable method for the determination of polycyclic aromatic hydrocarbons (PAHs) in water samples by solid-phase extraction (SPE) using centrifugation has been developed and optimized. A silica-based C18 cartridge was used; parameters affecting the extraction procedure such as type and volume of the elution solvent, breakthrough volume of the percolated water sample, drying of the sorbent, and evaporation of the elute have been studied. The innovation of this work was the examination of the use of a centrifugation technique in both the drying and elution steps. When combined with centrifugation, the volume of the elution solvent was reduced to 1 mL and the time for sorbent drying decreased also to 10 min under vacuum. Under optimal conditions, recoveries for the 16 U.S. EPA PAHs were between 70 and 85% and the relative standard deviation varied between 1 and 14%. Surrogate standard recoveries were similarly between 61 and 94% with a relative standard deviation between 2 and 15%. The simplicity of the described method, use of less of organic solvent, short procedure time, and good recoveries demonstrate the advantages of this environmentally friendly approach for routine analysis of numerous samples. © 2011 American Chemical Society.


Mokh S.,National Council for Scientific Research CNRS | El Hawari K.,National Council for Scientific Research CNRS | Nassar R.,Lebanese University | Budzinski H.,University of Bordeaux 1 | And 2 more authors.
Chromatographia | Year: 2015

A new and simple method has been developed for determination and quantification of 12 aminoglycosides in environmental water samples. The method is based on solid-phase extraction (SPE) followed by liquid chromatography coupled with tandem mass spectrometry (LC–ESI–MS/MS) for analysis. After optimization of LC–ESI–MS/MS conditions, two SPE cartridges, reversed-phase C18 with pentafluoropropionic acid (PFPA) and polymeric mixed mode cation exchange cartridges, have been tested to determine aminoglycoside residues in water. Parameters affecting the extraction efficiency for the two cartridges such as eluent type, percolation volume and percentage of ion pair PFPA were optimized. Extraction on C18 cartridges with PFPA reagent showed a better result in terms of recovery (65–115 %) and relative standard deviation (0.5–15 %) relative to strong cation exchange. This method was validated and their limits of quantification were in the range 5–50 ng L−1. The method was applied to evaluate the occurrence of these compounds in influent and effluent wastewater treatment plant and hospital water samples in Lebanon. Gentamycin was found in hospital wastewater samples at a concentration of 30 ng L−1. © 2015, Springer-Verlag Berlin Heidelberg.


Darwish T.,Center for Remote Sensing, Inc. | Khater C.,Center for Remote Sensing, Inc. | Jomaa I.,Center for Remote Sensing, Inc. | Stehouwer R.,Pennsylvania State University | And 2 more authors.
Land Degradation and Development | Year: 2011

Years of unregulated mining activity have left hundreds of abandoned quarries across Lebanon. Satellite images show that the number of quarries and areas they cover increased, from 784 quarries covering 2897ha in 1989, to 1278 quarries covering 5267ha in 2005. This paper presents a comprehensive approach to assess the impact of quarrying activities on scarce Eastern Mediterranean natural resources. The assessment is based on the computation of spatial indicators such as rainfall, slope gradient, vegetation cover, soil erosion risk, and rock infiltration, using GIS to appraise critical impacts on the Lebanese ecosystem. Compared with the 1989 baseline, the area consumed by quarries in 2005 increased more than three times over former arable lands, one third for forest lands and doubled for pasture lands. Quarries additionally destroyed 676, 137, and 737ha of productive lands, respectively. The comparison of quarry distribution with the land capability map revealed that quarries are found mainly on productive soils, consuming 1314ha in 1989 and 2192ha in 2005 of prime lands. A total of 87 per cent of studied quarries represent serious hazards to groundwater quality. In general, a total of 272 quarries have high impact, 657 quarries have moderate impact, and 349 quarries have low impact on natural ecosystems. Analyzed data revealed that around 62 per cent of the quarries are located in a highly unsuitable environment. This paper presents recent findings from the Eastern Mediterranean for territorial suitability assessment of quarries to be considered in the frame of natural resources and coastal ecosystems management. Copyright © 2010 John Wiley & Sons, Ltd.


Merhy M.,Brest National School of Engineering | Merhy M.,Lebanese University | Benzinou A.,Brest National School of Engineering | Nasreddine K.,Brest National School of Engineering | And 2 more authors.
5th International Conference on Image Processing, Theory, Tools and Applications 2015, IPTA 2015 | Year: 2015

In this paper, we address the problem of shape part recognition. For this purpose, we define a robust distance between shape parts based on geodesics in the shape space. The proposed distance uses an elastic shape matching to handle elastic deformations and compare shape parts locally. This distance is applied to shape part classification and shape part retrieval. An experimental study through the MPEG-7 shape database demonstrates that our proposed method outperforms existing schemes for shape part recognition. © 2015 IEEE.


Merhy M.,Brest National School of Engineering | Merhy M.,Lebanese University | Benzinou A.,Brest National School of Engineering | Nasreddine K.,Brest National School of Engineering | And 2 more authors.
2015 23rd European Signal Processing Conference, EUSIPCO 2015 | Year: 2015

The quality of the segmentation process directly affects the performance of the shape recognition. In this paper, we address the problem of shape recognition using only the available shape parts instead of the whole shape. For this purpose, we propose a shape parts recognition strategy that uses a robust distance based on geodesics in the shape space. The proposed combining strategy seeks to handle the contour discontinuity can occur in edge maps due to various disturbing factors encountered in real images. The experimental validation through the MPEG-7 shape database and some real images demonstrates the efficiency of our proposed approach. © 2015 EURASIP.


PubMed | National Council for Scientific Research CNRS
Type: Journal Article | Journal: Journal of invertebrate pathology | Year: 2011

A survey of entomopathogenic nematodes in Lebanon was conducted for the first time during 2008-2009. Samples were collected on the coastal strip and in nine vegetation types extending from the coastal line to 3088m above sea level. Wooded and herbaceous ecosystems were considered for sampling purposes. A total of 570 samples were taken, out of which 1% were positive for entomopathogenic nematodes. Approximately, 15.8% out of the 19 sites sampled revealed entomopathogenic nematodes presence (representing three samples). Two entomopathogenic nematodes species Heterorhabditis bacteriophora and Steinernema feltiae were recovered, and identification of their symbiotic bacteria revealed the presence of a Xenorhabdus bovienii, Photorhabdus temperata subsp. thracensis, Photorhabdus luminescens subsp. kayaii and Photorhabdus luminescens subsp. Laumondii.

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