Effect of friction deformation on the structure and properties of a metastable austenitic chromium-nickel steel

The effect of surface friction deformation on the phase composition, structure, and strength properties of a ribbon produced from a chromium-nickel steel with metastable austenite is studied. It is shown that friction processing intensifies the γ-α transformation, creating favorable conditions for the formation of a highly dispersed structure in a thin surface layer and, thus, increasing the microhardness, the elastic limit, the fatigue stability, and the Bauschinger effect. © 2013 Pleiades Publishing, Ltd

Interactions in vivo between the Vif protein of HIV-1 and the precursor (Pr55GAG) of the virion nucleocapsid proteins

The abnormality of viral core structure seen in vif-defective HIV-1 grown in PBMCs has suggested a role for Vif in viral morphogenesis. Using an in vivo mammalian two-hybrid assay, the interaction between Vif and the precursor (Pr55GAG) of the virion nucleocapsid proteins has been analysed. This revealed the amino-terminal (aa 1–22) and central (aa 70–100) regions of Vif to be essential for its interaction with Pr55GAG, but deletion of the carboxy-terminal (aa 158–192) region of the protein had only a minor effect on its interaction. Initial deletion studies carried out on Pr55GAG showed that a 35-amino-acid region of the protein bridging the MA(p17)–CA(p24) junction was essential for its ability to interact with Vif. Site-directed mutagenesis of a conserved tryptophan (Trp21) near the amino terminus of Vif showed it to be important for the interaction with Pr55GAG. By contrast, mutagenesis of the highly conserved YLAL residues forming part of the BC-box motif, shown to be important in Vif promoting degradation of APOBEC3G/3F, had little or no effect on the Vif–Pr55GAG interaction

Modulation of NKp30- and NKp46-Mediated Natural Killer Cell Responses by Poxviral Hemagglutinin

Natural killer (NK) cells are an important element in the immune defense against the orthopox family members vaccinia virus (VV) and ectromelia virus (ECTV). NK cells are regulated through inhibitory and activating signaling receptors, the latter involving NKG2D and the natural cytotoxicity receptors (NCR), NKp46, NKp44 and NKp30. Here we report that VV infection results in an upregulation of ligand structures for NKp30 and NKp46 on infected cells, whereas the binding of NKp44 and NKG2D was not significantly affected. Likewise, infection with ectromelia virus (ECTV), the mousepox agent, enhanced binding of NKp30 and, to a lesser extent, NKp46. The hemagglutinin (HA) molecules from VV and ECTV, which are known virulence factors, were identified as novel ligands for NKp30 and NKp46. Using NK cells with selectively silenced NCR expression and NCR-CD3ζ reporter cells, we observed that HA present on the surface of VV-infected cells, or in the form of recombinant soluble protein, was able to block NKp30-triggered activation, whereas it stimulated the activation through NKp46. The net effect of this complex influence on NK cell activity resulted in a decreased NK lysis susceptibility of infected cells at late time points of VV infection when HA was expression was pronounced. We conclude that poxviral HA represents a conserved ligand of NCR, exerting a novel immune escape mechanism through its blocking effect on NKp30-mediated activation at a late stage of infection

The Prevalence of Irritable Bowel Syndrome Symptoms in High School Students in Abadan City in 2016

Background and Purpose: Irritable bowel syndrome (IBS) is a chronic functional bowel disorder that is thought to be due to a disorder of brain-gut function and a chronic and debilitating functional gastrointestinal disorder that affects 9-23 of the population across the world. This problem (IBS) is the second cause of absenteeism from the work and school, too. There is classification system for IBS (Rome IV classification system). Method: The purpose of this descriptive cross-sectional study was determination Prevalence of Irritable Bowel Syndrome Symptoms in High School female Students in Abadan City in 2016. In this study, using a two-part questionnaire designed by the researcher, one part of which was demographic information, and the second part was IBS symptoms, 1044 girls were classified using random sampling method. After collecting data, data were analyzed by SPSS software version 19 and descriptive statistics tests. P value less than 0.05 was considered significant. Findings: The age range of participants was between the ages of 14 and 18 and their mean age was 16 +/- 2. The findings of this study showed that the most common symptoms of IBS include abdominal pain (66.4), diarrhea (46.7), constipation (42.5). Conclusion: According to the results of the study, it can be said that the symptoms of IBS are high among high school female students, thus clarifying the need for more attention to this issue

Hydrogenic impurity states in zinc-blende InxGa1-xN/GaN in cylindrical quantum well wires under hydrostatic pressure

Within the framework of effective-mass approximation, the binding energy of a hydrogenic donor impurity in zinc-blende (ZB) InxGa1-xN/GaN cylindrical quantum well wires (CQWWs) is investigated using variational procedures. Numerical results show that the ground-state donor binding energy E-b increases when the hydrostatic pressure increases for any impurity position. The donor binding energy for a shallow donor impurity located at the center of the CQWWs is the largest. Also, we have found that In concentration is very important value to tailor the system, since the binding energies close to binding energy maxima are strongly dependent to In content. (C) 2011 Elsevier B.V. All rights reserved.[CUBAP F-238]; [TUBITAK 108T015]The authors acknowledge the support of the grants CUBAP F-238, TUBITAK 108T015