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Ghebouli B.,Oran University of Science and Technology - Mohamed Boudiaf | Ghebouli M.A.,Center University | Fatmi M.,Oran University of Science and Technology - Mohamed Boudiaf | Bouhemadou A.,Ferhat Abbas University Setif | Bouhemadou A.,King Saud University
Solid State Communications | Year: 2010

The structural, elastic, electronic, optical and thermodynamic properties of the perovskite chloride CsCdCl3 were investigated using the pseudo-potential plane wave (PP-PW) within the Generalized Gradient Approximation (GGA) and Local Density Approximation (LDA). The computed lattice parameter agrees well with experimental and previous theoretical works. Based on the elastic constants and their related parameters, the crystal rigidity and mechanical stability have been discussed. Energy band structure shows that the investigated material is ΓR indirect energy band gap semiconductor. The static dielectric constant and static refractive index are indeed, proportional to the fundamental indirect band gap. The thermal effect on the lattice parameter, bulk modulus, volume expansion coefficient, Grneisen parameter, heat capacities and Debye temperature were predicted using the quasi-harmonic Debye model. To the best of the authors' knowledge, most of the studied properties are reported for the first time. © 2010 Elsevier Ltd. All rights reserved.

Janke C.,Center University | Bulinski J.C.,Columbia University
Nature Reviews Molecular Cell Biology | Year: 2011

Half a century of biochemical and biophysical experiments has provided attractive models that may explain the diverse functions of microtubules within cells and organisms. However, the notion of functionally distinct microtubule types has not been explored with similar intensity, mostly because mechanisms for generating divergent microtubule species were not yet known. Cells generate distinct microtubule subtypes through expression of different tubulin isotypes and through post-translational modifications, such as detyrosination and further cleavage to Î "2-tubulin, acetylation, polyglutamylation and polyglycylation. The recent discovery of enzymes responsible for many tubulin post-translational modifications has enabled functional studies demonstrating that these post-translational modifications may regulate microtubule functions through an amazing range of mechanisms. © 2011 Macmillan Publishers Limited. All rights reserved.

Chakraborti S.,Bose Institute of India | Chakraborti S.,Center University | Mandal A.K.,North Bengal University | Mandal A.K.,Vidyasagar University | And 4 more authors.
Colloids and Surfaces B: Biointerfaces | Year: 2014

Zinc oxide nanoparticles (ZnO-NP) were synthesized by alcoholic route using zinc acetate as the precursor material and lithium hydroxide as hydrolyzing agent. Further ZnO-PEI NP (derivative of ZnO-NP) was made in aqueous medium using the capping agent polyethyleneimine (PEI). The nanoparticles were characterized by XRD measurements, TEM and other techniques; the weight % of coating shell in the polymer-capped particles was determined by TGA. ZnO-PEI NP is more soluble in water than the uncapped ZnO-NP, and forms a colloidal suspension in water. PEI-capped ZnO-NP exhibited better antibacterial activity when compared with that of uncapped ZnO-NP against a range of multiple-antibiotic-resistant (MAR) Gram-negative bacterial strains harboring genes of high-pathogenicity island. ZnO-NP effectively killed these microorganisms by generating reactive oxygen species (ROS) and damaging bacterial membrane. ZnO-PEI NP at LD50 dose in combination with tetracycline showed synergistic effect to inhibit tetracycline-resistant Escherichia coli MREC33 growth by 80%. These results open up a new vista in therapeutics to use antibiotics (which have otherwise been rendered useless against MAR bacteria) in combination with minimized dosage of nanoparticles for the more effective control of MAR pathogenic bacteria. © 2014 Elsevier B.V.

Mahcene H.,University of Ouargla | Moussa H.B.,University of Batna | Bouguettaia H.,University of Ouargla | Bechki D.,University of Ouargla | And 2 more authors.
International Journal of Hydrogen Energy | Year: 2011

A two-dimensional mathematical model for a planar SOFC (solid oxide fuel cell) is constructed. The distribution of the chemical species, the temperature and the performance (power) and the current density were calculated using a single-unit model with double channels of co-flow pattern. The finite volume method was employed for the calculation. The method was based on the fundamental conservation laws of continuity, momentum, energy and mass. The equations are implemented in FORTRAN language. The effects of several heat sources and flow rates on the calculated results were also investigated. The reference SOFC polarization curve has been calculated by imposing a uniform temperature of 800 K, a pressure equal to 1 atm; H2 and O2 molar fractions equal to 0.97 and 0.21 respectively. Results of temperature, chemical species distributions, performance and efficiency under several heat sources are shown and discussed. At a current density of about 23500 A/m2, the power densities under all sources and chemical sources reached their maximums of 12965 W/m2 and 16209 W/m2 (i.e. 25% lower) respectively. However the temperature increment in the anode is analyzed toward all sources and chemical reaction. The temperature maximum values for each heat source type reached 1005.81 K and 984.69 K respectively. © 2010, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Waibel M.,The Peter MacCallum Cancer Center | Solomon V.S.,The Peter MacCallum Cancer Center | Knight D.A.,The Peter MacCallum Cancer Center | Ralli R.A.,The Peter MacCallum Cancer Center | And 21 more authors.
Cell Reports | Year: 2013

To design rational therapies for JAK2-driven hematological malignancies, we functionally dissected the key survival pathways downstream of hyperactive JAK2. In tumors driven by mutant JAK2, Stat1, Stat3, Stat5, and the Pi3k and Mek/Erk pathwayswere constitutively active, and gene expressionprofiling of TEL-JAK2 T-ALL cells revealed theupregulation of prosurvival Bcl-2 family genes. Combining the Bcl-2/Bcl-xL inhibitor ABT-737 with JAK2 inhibitors mediated prolonged disease regressions and cures in mice bearing primary human andmouse JAK2 mutant tumors. Moreover, combined targeting of JAK2 and Bcl-2/Bcl-xL was ableto circumvent and overcome acquired resistance to single-agent JAK2 inhibitor treatment. Thus, inhibiting the oncogenic JAK2 signaling network at two nodal points, at the initiating stage (JAK2) and the effector stage (Bcl-2/Bcl-xL), is highly effectiveand provides a clearly superior therapeutic benefitthan targeting just one node. Therefore, we have defined a potentially curative treatment for hematological malignancies expressing constitutively active JAK2.

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