Filogenetska analiza gena za hemaglutinin podtipa H9N2 virusa influence ptica izdvojenih iz tovnih pilića u Iranu.

In the present study, the genetic variations were examined of hemagglutinin genes of 4 recent H9N2 subtype avian influenza viruses isolated in the Tehran province of Iran. These hemagglutinin genes were amplified and sequenced in order to compare these viruses with the previous isolates from Iran and some other countries from all over the world. The full length hemagglutinin genes of 112 H9N2 avian influenza strains isolated from chickens, and also migratory birds from all over the world, including 68 strains isolated in Iran during 1998-2012, were genetically analyzed. The amino acids in the hemagglutinin cleavage site of the all 4 recent isolates possessed a PAKSSR/GL motif, which is a different motif when compared with the predominant PARSSR/GL motif in the hemagglutinin of the Iranian H9N2 strains isolated before 2010. All 4 recent isolates possessed histidine, alanin, leucine and isoleucine at positions 183, 190, 226 and 227 respectively, which are the key residues in receptor-binding sites. Genetic and phylogenetic analysis of the hemagglutinin genes showed that recent H9N2 strains isolated from chickens in Iran during 2010-2012, formed a distinct subgroup of the previous strains. Recent changes in the H9N2 viruses may be the result of the widespread circulation of these viruses in recent years. This may be due to the lack of adequate surveillance and control programs, such as vaccination and quarantine. Hence, it is highly recommended that continuous surveillance programs and genetic analysis of ongoing changes to H9N2 should be considered.Istražene su inačice gena za hemaglutinin četiriju nedavno izdvojenih izolata podtipa H9N2 virusa influence ptica na području Teherana u Iranu. Geni su umnoženi i sekvencirani s ciljem da se obilježja virusa usporede s prijašnjim izolatima iz Irana i nekih drugih zemalja u svijetu. Analizirani su geni za hemaglutinin u punoj dužini od 112 izolata H9N2 iz pilića i ptica selica iz cijelog svijeta, uključujući i 68 izolata iz Irana od 1998. do 2012. Aminokiselinski sastav na mjestu cijepanja hemaglutinina svih četiriju nedavno izdvojenih izolata sadržavao je PAKSSR/GL motiv, koji je bio različit u usporedbi s prevladavajućim PARSSR/GL u hemaglutininu iranskih sojeva H9N2 izdvojenih prije 2010. Sva četiri izolata posjedovala su histidin, alanin, leucin i izoleucin na pozicijama 183, 190, 226 i 227, koje su ključne za vezanje na receptore. Genetska i filogenetska analiza gena za hemaglutinin pokazala je da izolati H9N2 iz pilića u Iranu izdvojeni od 2010. do 2012. čine posebnu i različitu podskupinu od prijašnjih izolata. Dokazane izmjene tih izolata mogle bi biti uzrok njihova širenja posljednjih godina. To se moglo dogoditi zbog nedostatka odgovarajućeg programa nadzora i kontrole koji bi obuhvaćali cijepljenje i karantenu. Stoga se posebice preporučuje provođenje programa genetske analize te trajnog praćenja trenutnih promjena podtipa H9N2

Numerical simulation of crack propagation behavior of a semi-cylindrical specimen under dynamic loading

To design and evaluate the analytical crack propagation of a specimen under dynamic load, measurement of dynamic fracture parameters is necessary. However, analytical methods have significant complexity, and experimental methods are also time-consuming that require high precision and considerable funding. Therefore, numerical methods can be used to solve these problems. The Extended Finite Element Method (X-FEM) as a powerful and efficient tool can be used for this purpose. In this paper, X-FEM code in ABAQUS software was used in order to simulate crack growth in a semi-circular specimen with pre-existed crack and also intact specimen to determine dynamic stress intensity factor (DSIF) using displacement extrapolation method. To verify the numerical modeling output, the curve of crack surface opening displacement (CSOD) in X-FEM model has been compared with the experimental curve. Moreover, concrete damage plastic (CDP) model was used to validate X-FEM simulation results. The results show that the DSIF for a cracked sample under a maximum dynamic load 3000 N is equal to 0.5 Mpa . Comparison between the CDP and X-FEM results showed that in both approaches, the same area for crack propagation was also determined

Self-organization of an optomagnetic CoFe2O4-ZnS nanocomposite : preparation and characterization

We report an advanced method for the self-organization of an optomagnetic nanocomposite composed of both fluorescent clusters (ZnS quantum dots, QDs) and magnetic nanoparticles (CoFe2O4). ZnS nanocrystals were prepared via an aqueous method at different temperatures (25, 50, 75, and 100 degrees C). Their structural, optical and chemical properties were comprehensively characterized by X-ray diffraction (XRD), UV-vis, photoluminescence (PL) spectroscopy, scanning electron microscopy (SEM), dynamic light scattering (DLS), transmission electron microscopy (TEM), and infrared spectroscopy (FT-IR). The highest PL intensity was observed for the cubic ZnS nanoparticles synthesized at 75 degrees C which were then stabilized electrosterically using thioglycolic acid. The photophysical analysis of the capped QDs with a particle size in the range 9-25 nm revealed that the emission intensity and the optical band gap increases compared to uncapped nanocrystals (3.88 to 4.02 eV). These band gaps are wider than that of bulk ZnS resulting from the quantum confinement effect. Magnetic nanoparticles were synthesized via a co-precipitation route and a sol-gel process was used to form the functionalized, silica-coated CoFe2O4. Finally, thiol coordination was used for binding the QDs to the surface of the magnetic nanoparticles. The fluorescence intensity and magnetic properties of the nanocomposites are related to the ratio of ZnS and CoFe2O4. An optomagnetic nanocomposite with small size (12-45 nm), acceptable saturation magnetization (about 6.7 emu g(-1)), and satisfactory luminescence characteristics was successfully synthesized. These systems are promising candidates for biological and photocatalytic applications

Silica-Silicon Composites for Near-Infrared Reflection: A Comprehensive Computational and Experimental Study

Compact layers containing embedded semiconductor particles consolidated using pulsed electric current sintering exhibit intense, broadband near-infrared reflectance. The composites consolidated from nano- or micro-silica powder have a different porous microstructure which causes scattering at the air-matrix interface and larger reflectance primarily in the visible region. The 3 mm thick composite compacts reflect up to 72% of the incident radiation in the near-infrared region with a semiconductor microinclusion volume fraction of 1% which closely matches predictions from multiscale Monte Carlo modeling and Kubelka-Munk theory. Further, the calculated spectra predict an improvement of the reflectance by decreasing the average particle size or broadening the standard deviation. The high reflectance is achieved with minimal dissipative losses and facile manufacturing, and the composites described herein are well-suited to control the radiative transfer of heat in devices at high temperature and under harsh conditions.Comment: 9 pages, 5 figure

Domestic greywater treatment using electrocoagulation-electrooxidation process: optimisation and experimental approaches

A synergistic combination of electrocoagulation-electrooxidation (EC-EO) process was used in the current study to treat domestic greywater. The EC process consisted of an aluminium (Al) anode and an iron (Fe) cathode, and the EO process consisted of titanium with platinum coating mesh (Ti/Pt) as an anode and stainless steel as a cathode. The effect of operative variables, namely current density, pH, EC time and EO time, on the removal of chemical oxygen demand (COD), colour, turbidity, and total organic carbon (TOC) was studied and optimised using Response Surface Methodology (RSM). The results showed that although the pH affected the removal of all studied pollutants, it had more effect on turbidity removal with a contribution of 88.44%, while the current density had the main dominant effect on colour removal with a contribution of 73.59%. It was also found that at optimal operation conditions for a current density of 2.6 A, an initial pH of 4.67, an EC time of 31.67 min, and an EO time of 93.28 min led to a COD, colour, turbidity, and TOC removal rates of 96.1%, 97.5%, 90.9%, and 98%, respectively, which were close to the predicted results. The average operating cost and energy consumption for the removal of COD, colour, turbidity, and TOC were 0.014 $/m3 and 0.01 kWh/kg, 0.083$/m3 and 0.008 kWh/kg, 0.075 $/m3 and 0.062 kWh/kg, and 0.105$/m3 and 0.079 kWh/kg, respectively

A model of gaining customer loyalty through Customer Knowledge Management in banking industry of Iran (Private Banks)

According to the Importance of customer in competitive environment, especially in banking industry, regarding that the cost of catching (attracting) new customers is several times higher than the cost of keep customer loyal to organization, cause that examining ways of becoming loyal customer to product (goods/ services) has high preference in market research. This research, shows that we can catch loyalty through customer knowledge. The Concentration of private banks on five main elements in this research model, can help them having loyal customers. In order to reach that the model was based on the literature review and data were collected through questionnaire and has been analyzed with structural modeling and Lisrel software

Critical Success Factor in IT Project Risk Management in Virtual Enterprise: Multi Case Study

As spending on IT rises steeply, organizations become increasingly technology-dependent and, consequently, they become highly vulnerable to the risks of IT failure. The latest report on the failure of many complex IT projects to deliver key benefits on time and to target cost and specification was published jointly by the Royal Academy of Engineering and the British Computer Society. One of the key findings is that ‘‘risk management is critical to success in complex projects but is seldom applied effectively in the case of IT and software’’. On the other hand, Recent developments in global commerce have witnessed the advent of the virtual enterprise. Groups of companies are forming short-term relationships to collaborate on one-off projects. A VE face more risks than a stand-alone enterprise. Many factors, such as delivery performance, price and demand, etc., can cause risks

Enhancement of visible-light photo-activity of BiVO4

This study describes photophysical properties of pure and Ag-doped BiVO4 nanocrystals. Diffuse reflectance spectroscopy illustrated that the absorption of BiVO4:Ag increases due to prolong and suppress electron-hole pair recombination