The 86-kDa subunit of autoantigen Ku is a somatostatin receptor regulating protein phosphatase-2A activity

We previously reported the immunopurification of a somatostatin receptor from the human tumoral gastric cell HGT1 using the monoclonal antibody 30F3 (Reyl-Desmars, F., Le Roux, S., Linard, C., Benkouka, F., and Lewin, M. J. M. (1989) J. Biol. Chem. 264, 18789-18795). Screening of a lambda gt11 HGT1-cDNA library with 30F3 led us to isolate a cDNA encoding an 86-kDa polypeptide displaying 100% structural identity with the 86-kDa subunit (p86-Ku) of the Ku autoantigen. Recombinant p86 expressed in Escherichia coli cross-reacted with 30F3 and specifically bound [125I-Tyr11]somatstatin-14. Binding was totally displaced by somatostatin-14, somatostatin-28, and SMS 201-995, with IC50 values of 0.7, 1.0, and 1.2 nM, respectively. In a search for a biological effect associated with binding, we purified a 36-kDa, okadaic acid-sensitive phosphatase (protein phosphatase-2A (PP2A)) from rat gastric cytosol. PP2A catalyzed 32P release from p34cdc2-phosphorylated histone H1. However, PP2A-induced 32P release was concentration dependently inhibited by recombinant p86-Ku, with a decrease in maximal velocity without a change in Km. Steric exclusion high pressure chromatography indicated that the inhibition resulted from direct interaction of the enzyme with p86-Ku. Furthermore, it was antagonized by increased concentrations of somatostatin-14 and prevented by preincubating p86-Ku with 30F3. Given the key role played by PP2A in cell cycle regulation, the current findings suggest that p86-Ku could be a physiological target of somatostatin antiproliferative action.     

Benzylation of benzene and other aromatics by benzyl chloride over copper-mesoporous molecular sieves materials

The benzylation of benzene and substituted benzene reactions employing benzyl chloride as the alkylating agent over a series of copper-containing mesoporous silicas with different Cu contents has been investigated. These materials (Cu-HMS-n) have been characterised by chemical analysis, BET and XRD. The mesoporous copper-containing materials showed both high activity and high selectivity for the benzylation of benzene. The activity of these catalysts for the benzylation of different aromatic compounds is in the following order: benzene > toluene > p-xylene > anisole. The kinetics of benzene benzylation over these catalysts have also been investigated.     

Modulating the Ferromagnet/Molecule Spin Hybridization Using an Artificial Magnetoelectric

Spin‐polarized charge transfer at the interface between a ferromagnetic (FM) metal and a molecule can lead to ferromagnetic coupling and to a high spin polarization at room temperature. The magnetic properties of these interfaces can not only alter those of the ferromagnet but can also stabilize molecular spin chains with interesting opportunities toward quantum computing. With the aim to enhance an organic spintronic device's functionality, external control over this spin polarization may thus be achieved by altering the ferromagnet/molecule interface's magnetic properties. To do so, the magnetoelectric properties of an underlying ferroelectric/ferromagnetic interface are utilized. Switching the ferroelectric polarization state of a PbZr_0.2Ti_0.8O₃ (PZT) bottom layer within a PZT/Co/FePc‐based (Pc ‐ phthalocyanine) device alters the X‐ray magnetic circular dichroism of the Fe site within the phthalocyanine molecular top layer. Thus, how to electrically alter the magnetic properties of an interface with high spin polarization at room temperature is demonstrated. This expands electrical control over spin‐polarized FM/molecule interfaces, which is first demonstrated using ferroelectric molecules, to all molecular classes.     

Competitive biosorption of heavy metals from aqueous solutions onto <Emphasis Type="Italic">Streptomyces rimosus</Emphasis>

The aim of this study is the simultaneous biosorption of Cd⁺² and Ni⁺² on a dead biomass, Streptomyces rimosus pretreated with NaOH (0,1 M). Kinetic tests were carried out for the binary mixture (cadmium-nickel) during 6 hours contact time to ensure that balance was reached. The amounts adsorbed at equilibrium were 22.8 mg Ni²⁺/g and 9.86 mg Cd²⁺/g biomass, respectively. The biosorption depends mainly by some parameters, such as the pH, the initial concentration of metal and the initial concentration of biomass. The isotherm of adsorption according to two models, Langmuir and Freundlich, was carried out in our study. The results of the kinetics of adsorption show that the experimental values are well represented by the kinetic model of pseudo-second order. This enables us to determine the behavior of these adsorbents with respect to a real industrial effluent.     

Contribution to Nondestructive Testing Study Using Lorentz Force

Russian Journal of Nondestructive Testing - The Lorentz force is a new technique used recently for nondestructive testing (NDT) of conducting materials. Several scientific works have focused on the...     

A fair comparison of SAC-OCDMA system configurations based on two dimensional cyclic shift code and spectral direct detection

This paper investigates shortcomings that limit the performance of optical code division multiple access (OCDMA) systems including the low cardinality and data rate as well as the high power at reception. The main drawback for such systems known as multiple access interference accompanying by phase induced intensity noise is also investigated to effeciencly propose a novel two dimensional cyclic shift (2D-CS) code to be implemented in non-coherent OCDMA systems. The developed code is based on a one dimensional cyclic shift (1D-CS) code previously provided by research works processing spectral amplitude coding for optical code division multiple access (SAC-OCDMA) systems. Numerical results obtained by this study are therefore compared to previous studies employing different codes like two dimensional extended double weight (2D-EDW), two dimensional flexible cross correlation/modified double weight (2D-FCC/MDW), two dimensional perfect difference (2D-PD), two dimensional diluted perfect difference (2D-DPD), two dimensional multi service (2D-MS) and two dimensional zero cross correlation/multi diagonal (2D-ZCC/MD) codes. Accordingly, it is demonstrated that the proposed 2D-CS code outperforms all codes given previously in terms of system capacity where the small increasing percentage is about 40% compared to 2D-ZCC/MD and 2D-MS. Systems using 2D-CS code can support until 203 simultaneous users with a total code length equal to 171. System performance investigation leads to a BER and Q-Factor closely to1.0E?12 and 1.0E?27, and 6.6 dB and 10.6 dB at 20 km of single mode fiber length using white light source and Laser, respectively. Furthermore, such a code can be easily adopted by OCDMA systems for a long distance up to approximately 55 and 100 km.

     

Influence of BaTiO3 additive and electrode material onspace-charge formation in polyethylene. Evidence from thermal stepspace-charge measurements

The effects of 5% wt BaTiO₃ additive and of electrode material on space charge formation and electric field distribution in low density polyethylene (LDPE) were investigated using a thermal step technique. Space charge was formed at an average dc field of ~28 kV/mm and at 50°C. Results indicate that the addition of BaTiO₃ to LDPE has considerably reduced the remanent space charge and electric field and changed their distribution patterns in the doped material when compared with the plain material. It is also shown that the remanent space charge and electric field in plain LDPE are strongly dependent on the type of electrode material     

Application of the Indium-containing mesoporous silicas catalysts in the alkylation of aromatics reaction

The benzylation of benzene and substituted benzenes reaction employing benzyl chloride as the alkylating agent over a series of Indium-containing mesoporous silicas with different In contents has been investigated. These materials (In-HMS-n) have been characterized by chemical analysis, N₂ adsorption/desorption isotherm, X-ray diffraction (XRD) and FTIR spectroscopy. The mesoporous Indium-containing materials showed both high activity and high selectivity for benzylation of benzene. The activity of these catalysts for the benzylation of different aromatic compounds is in the following order: benzene > toluene > p-xylene > anisole. More interesting is the observation that these catalysts are always active and selective for large molecules like naphthenic compounds such as methoxynaphthalene. Kinetics of the benzene benzylation over these catalysts have also been investigated.     

Simultaneously efficient adsorption and photocatalytic degradation of sodium dodecyl sulfate surfactant by one-pot synthesized TiO2/layered double hydroxide materials

The large amount of surfactants discharge into wastewater are harmful for both terrestrial and aquatic life; in fact the removal of surfactants from wastewater becomes necessary. The present study is focused on to the removal of sodium dodecyl sulphate surfactant (SDS) by adsorption and photocatalytic degradation using Zn(2)Al-LDH and TiO₂/Zn(2)Al-LDH materials synthesized by co-precipitation. The experimental adsorption data obtained were evaluated using Langmuir Freundlich and Temkin isotherms models. The photocatalytic degradation activities of SDS at different concentration in the range of (10?100 mg/L) over Zn(2)Al-LDH and TiO₂/Zn(2)Al-LDH follows the pseudo first-order kinetics in accordance with the Langmuir Hinshelwood model. The results indicated that TiO₂(3.6)/Zn(2)Al-LDH show the highest photocatalytic activity compared to Zn(2)Al-LDH sample.