Syrian Atomic Energy Commission

Damascus, Syria

Syrian Atomic Energy Commission

Damascus, Syria
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The periplasmic binding protein (P39) antigen of Brucella melitensis 16 M was previously identified as Th1 dominant antigens. In this study, the potential for this antigen to function as vaccine against B. melitensis 16 M infection in BALB/c mice has been analyzed, and the humoral and cellular immune responses induced have been also characterized. Mice were injected intraperitoneally with live Escherichia coli alone or with that which express Brucella P39, two times at 4 weeks intervals. The live E. coli BL21 (DE3) pEt15b-p39 vaccine elicited a T-cell-proliferative response and also induced a gamma interferon production upon re-stimulation with either the bacterial extract or P39 as a specific antigen. Also the live E. coli BL21 (DE3) pEt15b-p39 vaccine has been found to induce a strong humoral response (IgG1 and IgG2a). Compared to the saline-inoculated control, vaccination of mice with E. coli BL21pEt15b-p39 at 3 weeks prior to the challenge infection, significantly reduced the number of strain 16 M bacteria in spleens at 4 and 8 weeks post-challenge infection in all vaccinated mice (p < 0.001). © 2009 Elsevier Ltd. All rights reserved.

Factor analysis technique is proposed in this research for interpreting the combination of nuclear well logging, including natural gamma ray, density and neutron-porosity, and the electrical well logging of long and short normal, in order to characterize the large extended basaltic areas in southern Syria. Kodana well logging data are used for testing and applying the proposed technique. The four resulting score logs enable to establish the lithological score cross-section of the studied well. The established cross-section clearly shows the distribution and the identification of four kinds of basalt which are hard massive basalt, hard basalt, pyroclastic basalt and the alteration basalt products, clay. The factor analysis technique is successfully applied on the Kodana well logging data in southern Syria, and can be used efficiently when several wells and huge well logging data with high number of variables are required to be interpreted. © 2013 Elsevier Ltd.

Al-Fares W.,Syrian Atomic Energy Commission
Journal of Applied Geophysics | Year: 2011

The objective of this work was to characterize and understand the origin of the water losses problem in the Afamia B dam located at Al-Ghab basin in Syria. The survey involved various geophysical methods including a superficial electromagnetic (EM), an electrical sounding (ES) and electrical resistivity tomography (ERT). Special considerations were focused on the lake of the dam, which is currently suffering serious water infiltration and leakage through its bedrocks. The application of the ERT technique was more effective and convenient. The analysis of the integrated results of the above mentioned methods revealed a vertical serious leakage which could take place in certain locations via fractures and faults that hit the main valley and pass through the dam lake. Additionally, the presence of an alternating lithological heterogeneity between permeable and impermeable layers may lead to infiltration through the geological formations of the basin. These processes are most likely causing hydraulic connections between the Neogene superficial deposits and the underlying Cretaceous fractured and karstified carbonates rocks. Consequently, such hydraulic connections may lead to water losses and leakage throughout the dam basin. Eventually, the presence of tens of drilled wells which penetrate the Neogene and Cretaceous formations, and the existence of numerous archeological graves and subsurface tunnels complicate the situation in the study area and cause more water leakage. © 2011 Elsevier B.V.

Al Lafi A.G.,Syrian Atomic Energy Commission
Polymers for Advanced Technologies | Year: 2014

This paper reports the first use of temperature-temperature 2D correlation dielectric relaxation spectroscopy (2D COS-DRS) to study the molecular relaxation dynamics in ion-irradiated poly(ether ether ketone) (PEEK). With the help of the high resolution and high sensitivity of 2D COS-DRS, it was possible to locate the position of the motion of water molecules in the dielectric spectrum of PEEK. This occurred at -20°C and increased in intensity on increasing water contents. On irradiation, a new relaxation was observed at -75°C and -85°C for proton and helium ion-irradiated samples, respectively. This increased in intensity on increasing radiation dose and was assigned to main-chain phenyl motions of the cross-linked units of the polymer. 2D COS-DRS was also successfully applied to resolve the overlap in molecular events in the region of glass transition. Three processes that change in different directions with respect to ion irradiation dose were identified. These were at 160°C, 175°C, and 240°C and were assigned to the α relaxation, second α relaxation, and the onset of conductivity, respectively. In addition, hybrid 2D COS-DRS was used to investigate the effect of the so-called linear energy transfer effect, and the results showed that helium ions were more effective in cross-linking PEEK. © 2013 John Wiley & Sons, Ltd.

Saour G.,Syrian Atomic Energy Commission
Florida Entomologist | Year: 2016

Flight abilities and dispersal distances of males of irradiated vs. untreated European grapevine moths (Lobesia botrana [Denis & Schiffermüller]: Lepidoptera: Tortricidae) were assessed in a flight assessment cage and in a vineyard. Newly emerged adult male moths were either untreated or γ-irradiated either with 150 Gy or 350 Gy, and each group was marked with a different colored fluorescent dust. Males were released in a laboratory flight assessment cage (70 × 40 × 50 cm) and at the center of a vineyard. The flight assessment cage test revealed significant differences in the flight responses of irradiated and untreated L. botrana males to calling females during the first 2 days after the initiation of the test. The greatest percentage of non-flying males (47%) was observed in the 350 Gy-treatment, whereas no significant differences were detected in male flight ability between untreated and 150 Gy γ-irradiated male moths. Six hundred male moths were released in a vineyard with a rectangular trapping grid around a central release point, and traps were baited with a synthetic pheromone. One hundred and thirty one males (21.8%) were recaptured, with the farthest being caught 40 m from the release point. No differences were observed in male field performance between 150 Gy γ-irradiated and untreated male moths, whereas 350 Gy γ-irradiated males showed limited field dispersal when compared with either 150 Gy γ-irradiated or untreated male moths. The results, the values of several attributes (flight ability, dispersal distance and recapture rate of released males in pheromone-baited traps)-which are critical for effective population suppression by the sterile insect technique with inherited or F1 sterility (SIT/F1)-were significantly decreased by increasing the radiation dose applied to L. botrana males from 150 Gy up to 350 Gy. The flight assessment cage proved to be a valuable tool for measuring differences in the quality of untreated and irradiated moths. © International Atomic Energy Agency 2016. Published by the Florida Entomological Society. All rights reserved.

Sakr N.,Syrian Atomic Energy Commission
Hellenic Plant Protection Journal | Year: 2014

Downy mildew in sunfl ower is a disease caused by Plasmopara halstedii, an oomycete with high virulence, aggressiveness and a great potential in developing new races. Understanding the pathogenic characteristics underlying virulence and aggressiveness processes by which P. halstedii rapidly evolves is essential to developing eff ective long-term control measures for the disease. In this review, new data are presented concerning all traits for the two components of pathogenicity (the evolution of virulence and aggressiveness) under diff erent categories of resistance selection pressure, the relationships among several morphological, genetic and pathogenic traits and the intervention between pathogenic variation and durable resistance in sunfl ower. By combining the data presented in this study, comprehension of the complex interaction between the pathogen and its host plant could be achieved. © Benaki Phytopathological Institute.

Al Lafi A.G.,Syrian Atomic Energy Commission
Polymer Degradation and Stability | Year: 2014

Attenuated total reflection Fourier transform infrared (ATR-FTIR) and two dimensional correlation (2D-COS) spectroscopies were used to follow the structural alteration occurring upon ion irradiation (H+ and He 2+) of films of poly (ether ether ketone), PEEK. Samples were exposed to ion irradiation doses up to 75 MGy in air atmosphere, and IR spectra were measured after ion irradiation and also for the gels after solvent extraction experiments. With the help of high resolution and high sensitivity 2D COS it was possible to obtain useful information about the different effects, types and mechanisms of reactions accompanying ion irradiation. Three main different effects of ion irradiation were observed. Oxidation manifested itself by the production of new carbonyl species absorbing in the IR at 1715 and 1745 cm -1 that were mainly present in the irradiated samples and attributed to fluorenone structures and to ester groups. Crosslinking occurred with the progressive development of new aromatic species absorbing at 1470, 870 and 810 cm-1 that were mainly present in the gels formed on irradiation. The formation of intermolecular crosslinks resulted in the increase in local ordering within the amorphous phase and orientation was observed to increase after ion irradiation by the progressive development of new bands at 1316, 1288, and 1240 cm-1. The different structures produced on irradiation with proton and helium ions were discussed and the analysis showed that helium ions were more effective in introducing the observed changes than protons. The infrared spectroscopy combined with 2D correlation provides a fast and powerful tool for polymer structure characterization. © 2014 Elsevier Ltd. All rights reserved.

Syrian Atomic Energy Commission | Date: 2012-03-21

A system and method are disclosed for determining the radiation dose distribution created by a set of radioactive seeds (20) placed in a volume (30). The method includes three stages. Stage T01 comprises preliminary steps that allow one to obtain the unit radiation dose distribution created by one seed and the individual attenuations created by its neighboring seeds when said neighboring seeds are assumed to be positioned at the nodes of a three-dimensional periodic lattice. Steps of stage T02 load some results of the preliminary steps, said results being used by steps of stage T03 that actually determine the dose distribution created by a set of seeds (20). The invention also relates to an apparatus, a program and a computer readable medium adapted for the execution of this method.

Al-Bachir M.,Syrian Atomic Energy Commission
Radiation Physics and Chemistry | Year: 2015

The effect of gamma radiation and storage on the characteristics of oil extracted from peanut seeds has been investigated in this study. Peanut seeds were undergone gamma irradiation process with the doses of 1, 2 and 3. kGy. The changes in chemical and physical attributes were observed immediately after irradiation and after 12 months of storage. The data obtained from the experiments showed that irradiation process had no effect on the chemical and physical qualities such as, fatty acid composition, peroxide value, iodine value specification number, TBA value and color of oil extracted from peanut seeds. On the contrary, the peroxide, acidity and TBA values of the peanut oil were decreased due to storage time. © 2014 Elsevier Ltd.

Haider N.,Syrian Atomic Energy Commission
Turkish Journal of Agriculture and Forestry | Year: 2012

The hexaploid bread wheat Triticum aestivum L. (AABBDD) is thought to have originated through one or more rare hybridization events between Aegilops tauschii (DD) and the tetraploid Emmer wheat T. turgidum subsp. dicoccon (AABB). The progenitor of the A genome of T. aestivum has generally been accepted to be T. urartu. The origin of the B genome, however, is controversial and still relatively unknown. Research has found the B genome in T. turgidum to be closely similar to the S genome in section Sitopsis of Aegilops L.; the Sitopsis diploid species were thus proposed as the probable maternal parent in the original cross that resulted in the tetraploid T. turgidum. Moreover, the donor of the cytoplasm of T. turgidum and T. aestivum was also the donor of most, if not all, of the B genome chromosomes. The present study attempts to investigate the polymorphism of chloroplast DNA between T. aestivum and 8 different Aegilops species using cleaved amplified polymorphic sequence (CAPS) and sequencing on 28 chloroplast loci in order to identify the chloroplast donor (B genome donor) of bread wheat. A phylogenetic tree based on the data generated demonstrates that Ae. speltoides was distinct from the other Aegilops species analyzed and the most closely related to bread wheat. It can be concluded that Ae. speltoides may be the chloroplast donor to bread wheat and the donor of its B genome. Understanding hexaploid wheat origin would further its genetic improvement and is also important for the artificial development of synthetic forms. © TÜBITAK.

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