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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. Source

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. Source

Al-Fares W.,Syrian Atomic Energy Commission
Journal of Applied Geophysics

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. Source

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. Source

Stable isotopes (δ 18O, δ 2H and 13C) and radioactivity ( 3H, 14C) have been used in conjunction with chemical data to evaluate the processes generating the chemical composition, reconstruct the origin of the water and groundwater residence time. The Aleppo basin is comprised of two main limestone aquifers: the first one is unconfined of Paleogene age and the second is confined of Upper Cretaceous age. The chemical data indicate that the dissolution of minerals and evaporation are the main processes controlling groundwater mineralization. The groundwater from the two aquifers is characterized by distinctive stable isotope signatures. This difference in water isotopes is interpreted in terms of difference origin and recharge period. Fresh and brackish shallow groundwater were mostly recharged during the Holocene period. The presence of 3H in several groundwater samples of this aquifer gives evidence that groundwater recharge is going on. Brackish water of the deep confined aquifer has depleted stable isotope composition and very low 14C activity that indicates recharge during the late Pleistocene cold period. © 2011 Springer-Verlag. Source

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