Background and purpose: Activation-induced cytidine deaminase (AID) is a B-cell specific enzyme responsible for somatic hypermutation (SHM) and class switch recombination (CSR) of antibody genes within the B-cell follicle of peripheral lymphoid organs. Ectopic overexpression of the enzyme leads to mutations in non-B cells and Escherichia coli (E. coli) genes. However, induction of mutations in E. coli by expression of AID requires highly regulated conditions. Therefore, the aim of this study was to construct a plasmid expressing AID under the control of tightly regulated temperature-sensitive promoter of bacteriophage lambda. . Materials and methods: The AID gene was isolated from PGEMT recombinant plasmid, containing AID and cloned into PTG19-T vector. Then, AID was ligated to an expression plasmid under the control of left promoter of bacteriophage lambda and mutant thermolabile cI857 repressor. Finally, the resistance marker of the engineered plasmid was replaced by tetracycline resistance gene. Results: The whole open reading frame of AID was ligated into a plasmid containing a cI857-sensitive receptor lambda bacteriophage. The sequence and reading frame accuracy of the cloning was confirmed by electrophoresis of PCR products on agarose gel, restriction enzyme digestion, and nucleotide sequencing methods. Conclusion: In current study, the AID was successfully cloned into an expression plasmid containing thermo-sensitive promoter of bacteriophage lambda. The recombinant plasmid could be used in different strains of E. coli to produce mutator strains.

In the present work, the in-flight kaon interaction on the deuteron target at incident momentum of is investigated in the channel by a phenomenological potential model. By considering the effect of resonance in the invariant mass spectra comes fromreaction, and a comparison between theoretical spectra and Braun’ s data, we found the best theoretical spectrum fitted to the experimental data. The energy and width of resonance state are respectively extracted and from the fitting process.

The aim of the present work is to introduce the concept of $\lambda _{r}$-almost convergence of sequences. We define the spaces $f\left( \lambda _{r}\right) $ and $f_{0}\left( \lambda _{r}\right) $ of $ \lambda _{r}$-almost convergent and $\lambda _{r}$-almost null sequences. We investigate some inclusion relations concerning those spaces with examples and we determine the $\beta $- and $\gamma $-duals of the space $f\left( \lambda _{r}\right) $. Finally, we give the characterization of some matrix classes.

The gene encoding extracellular thermostable carboxylesterase (estA) from Geobacillus thermoleovorans YN was fused to six-histidine and expressed under different promoters. Three different clones carrying this gene were constructed in host cell Escherichia coli BL21 (DE2) using three expression systems pET-17b, pBluescript ® II KS (+) and pCYTEX-P1 (pET-estA T7- promoter; pBlue-estA T7-promoter and pBlue-estA T7 promoter & Lambda pL promoter). The efficiency of expression of the three constructs was evaluated, where the highest esterase expression (589 u/ ml) using p-Nitrophenyl laurate as substrate (pNP-laurate: C18H27NO4) was measured under the control of T7-promoter in expression vector pET-17b after 4 h of the induction. A 1.5 fold increase in enzyme activity was measured with specific activity 1043 u/ mg protein on growing the clone expressed the target gene under T7-promoter (pET-estAT7) in 2-L working volume BIOFLO III bioreactor under optimal conditions. Recombinant expression of the tested thermostable esterase was monitored by sodium dodecyl sulphate polyacrylamid gel electrophoresis, zymogram and activity measurements with a--Naphthyl acetate (C12H10O2) and Fast Red. The SDS-PAGE analysis of E. coli BL21 (DE3)/pET-estA lysates indicated the presence of a protein band (29 kDa) related to the targeted expressed gene.

Optimized structural architect of an Unmanned Lambda Wing Aerial Vehicle (ULWAV) during conceptual design has proven to be a significant challenge due to its unconventional configuration and no historical data for the structural architect. This paper aims to develop a new approach for structural design layout of new generation unconventional aircraft especially for ULWAV. The first step in this approach is to investigate the affecting parameters on structural architecture of these aircrafts then using of modal analysis to identification the behavior of these unconventional geometries for a general methodology development. The result of this modal analysis is apportion aircraft geometry to conventional substructures with already well-established defined architect. ULWAV structure architecture has been done by combining the structural architecture of sub-sections and with respect to requirements for systems installation, stealth design objective and packaging requirements. Here the CATIA software is used to optimize general architect with parametric model. To validate the results, the maximum static stress and maximum displacement of the structure were calculated using MSC / Patran software and compared with the values obtained from the optimization process. Dynamic analysis and buckling stability of structural composite shells are also controlled below. The architect methodology was applied to a case study of an ULWAV. The weight of the optimized structure has also been confirmed by typical case study researches.

The study of classical Littlewood-Paley operators has an intrinsic interest for their essential role in harmonic analysis due to their applications in PDEs and other fields. One of the Littlewood-Paley operators is g λ *  operator which its p,p  strong boundedness depends on the parameter λ . For example, Fefferman showed strong boundedness of classical g λ *  for 1max 1, 2 p .  In this work, We consider the Laplace-Bessel differential operator and correspondingly we define the relevant Littlewood-Paley operator g B,λ *  to investigate both L p,ν - boundedness of g B,λ *  for 2≤P<∞  and λ>1+ 2v n and its unboundedness for 0