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Deir ez-Zor, Syria

Al-Furat University is a Syrian university; it is located in Deir ez-Zor and has campuses in other cities in Syria. It is a public university, founded in 2006. It is the fifth, and newest, university in Syria. Wikipedia.

Abed M.,University of Tubingen | Abed M.,Al-Furat University | Towhid S.T.,University of Tubingen | Mia S.,University of Tubingen | And 6 more authors.
American Journal of Physiology - Cell Physiology

Eryptosis, the suicidal erythrocyte death, leads to cell shrinkage and cell membrane scrambling with phosphatidylserine exposure at the cell surface. Eryptotic erythrocytes adhere to the vascular wall by binding of phosphatidylserine to the CXC chemokine ligand 16 (CXCL16). Stimulators of eryptosis include increased cytosolic Ca2+ activity, energy depletion, and activation of ceramide-producing sphingomyelinase. The present study explored whether sphingomyelinase triggers erythrocyte adhesion to endothelial cells. To this end, human erythrocytes were exposed for 6 h to bacterial sphingomyelinase (1-10 mU/ml) and phosphatidylserine exposure was estimated from fluorescent annexin-V-binding, cell volume from forward scatter in FACS-analysis, erythrocyte adhesion to human umbilical vein endothelial cells (HUVEC) from trapping of labeled erythrocytes in a flow chamber under flow conditions at arterial shear rates, and CXCL16 protein abundance utilizing Western blotting and FACS analysis of fluorescent antibody binding. As a result, sphingomyelinase (≥1 mU/ml) triggered cell shrinkage, phosphatidylserine exposure and erythrocyte adhesion to HUVEC, effects blunted by Ca2+ removal. Adhesion was significantly blunted by phosphatidylserine-coating annexin-V (5 μl/ml), following addition of neutralizing antibodies against endothelial CXCL16 (4 μg/ml) and following silencing of the CXCL16 gene with small interfering RNA. Pretreatment of HUVEC with sphingomyelinase upregulated CXCL16 protein abundance. Six hours pretreatment of HUVEC with sphingomyelinase (10 mU/ml) or C6-ceramide (50 μM) augmented erythrocyte adhesion following a 30-min treatment with Ca2+ ionophore ionomycin (1 μM) or following energy depletion by 48-h glucose removal. Thus exposure to sphingomyelinase or C6-ceramide triggers eryptosis followed by phosphatidylserine- and CXCL16-sensitive adhesion of eryptotic erythrocytes to HUVEC. © 2012 the American Physiological Society. Source

Molina R.,University of Oxford | Al-Salama Y.,Al-Furat University | Jurkschat K.,University of Oxford | Dobson P.J.,University of Oxford | Thompson I.P.,University of Oxford

The fate of nanomaterials when they enter the environment is an issue of increasing concern and thus it is important to know how they interact with natural organic molecules since this may have a significant impact on the particles' behavior. Because of our poor knowledge in this regard, the interaction of ZnO nanoparticles with amino acids of contrasting surface charge, including Histidine (HIS), Glycine (GLY), Aspartic acid (ASP) and Glutamic acid (GLU) which occur commonly in natural habitats, such as the plant root zone, was investigated over a range of pH conditions and concentrations. The addition of the individual amino acid led to significant changes in nanoparticle colloidal zeta potential stability, particle size distribution and the extent of agglomeration. Variations in pH resulted in considerable changes in nanoparticle surface charge and hydrodynamic size. In general, the particle size distribution decreased as the amino acid concentration increased, with more acidic conditions exacerbating this effect. In addition, increased concentrations of amino acids resulted in more stable nanoparticles in aqueous suspensions. Histidine had the greatest effect on colloidal stability, followed by Glycine, Aspartic acid and finally Glutamic acid. This study illustrates how nanoparticle behavior may change in the presence of naturally occurring amino acids, an important consideration when assessing the fate of nanoparticles in the environment. Additionally, utilization of amino acids in industrial processes could reduce particle agglomeration and it could lead to a way of employing more sustainable reagents. © 2010 Elsevier Ltd. Source

Abed M.,University of Tubingen | Abed M.,Al-Furat University | Feger M.,University of Tubingen | Alzoubi K.,University of Tubingen | And 5 more authors.
Kidney and Blood Pressure Research

Background/Aims: Klotho deficiency results in excessive formation of 1,25(OH)2D3, accelerated ageing and early death. Moreover, klotho deficiency enhances eryptosis, the suicidal erythrocyte death characterized by phosphatidylserine exposure at the erythrocyte surface. Triggers of eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i), glucose depletion, hyperosmotic shock and oxidative stress. Klotho expression is decreased and 1,25(OH)2D 3-formation enhanced by dehydration. The present study thus explored whether dehydration influences eryptosis. Methods: Blood was drawn from hydrated or 36h dehydrated mice. Plasma osmolarity was determined by vapour pressure method, plasma 1,25(OH)2D3 and aldosterone concentrations using ELISA, and plasma Ca2+-concentration utilizing photometry. Erythrocytes were exposed to Ca2+-ionophore ionomycin (1 μM, 30 min), energy depletion (12 h glucose removal), hyperosmotic shock (500 mM sucrose added, 2 h) and oxidative stress (100 μM tert-butyl-hydroperoxide, 30 min) and phosphatidylserine exposure at the erythrocyte surface estimated from annexin V binding. Results: Dehydration increased plasma osmolarity and plasma 1,25(OH)2D3 and aldosterone concentrations. Dehydration did not significantly modify phosphatidylserine-exposure of freshly drawn erythrocytes but significantly enhanced the increase of phosphatidylserine- exposure under control conditions and following treatment with ionomycin, glucose-deprivation, hyperosmolarity or tert-butyl-hydroperoxide. Conclusions: Dehydration sensitizes the erythrocytes to spontaneous eryptosis and to the triggering of eryptosis by excessive Ca2+-entry, energy depletion, hyperosmotic shock and oxidative stress. © 2013 S. Karger AG, Basel. Source

Mahdi M.C.,Al-Furat University
Artificial Satellites

Orbit design for KufaSat Nano-satellites is presented. Polar orbit is selected for the KufaSat mission. The orbit was designed with an Inclination which enables the satellite to see every part of the earth. KufaSat has a payload for imaging purposes which require a large amount of power, so the orbit is determined to be sun synchronous in order to provide the power through solar panels. The KufaSat mission is designed for the low earth orbit. The six initial Keplerian Elements of KufaSat are calculated. The orbit design of KufaSat according to the calculated Keplerian elements has been simulated and analyzed by using MATLAB first and then by using General Mission Analysis Tool. © 2015 Artificial Satellites. Source

Hussein M.T.,University of Babylon | Nemah M.N.,Al-Furat University
International Conference on Robotics and Mechatronics, ICROM 2015

This research clarifies the control problem of quadrotor system using PD control. In order to design the control a nonlinear dynamic model of the quadrotor system is derived. The dynamic model contains set of equations valid for hovering. Those set of equations evolved a complex mathematical model with more realistic aerodynamic coefficients and actuator models. Two different control loops are designed in this work to control the motion of the quadrotor system. While the first loop is used to control position of the system; the second loop is utilized to control the orientation. The estimated control inputs are updated based on direct feedback of orientation and the position of the system. The simulation results show the effectiveness of overall systems model and the presented control approach. The work will be expanded later; where off-board test-rig can be used to test the suggested control approach. © 2015 IEEE. Source

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