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Birjand, Iran

Birjand University of Medical science is a medical school in Iran.Located in Birjand of South Khorasan Province, the school was founded in 1985 under the supervision of Mashhad University of Medical science, but was separated later as an independent institute.The university is state operated, and currently trains 1,800 students in 13 departments in 5 Colleges of Nursing & Midwifery, Health science, Medicine, Para-clinical science and Dentistry as well as 3 satellite schools.The University operates two teaching hospitals and 10 clinics in the area. Wikipedia.

Common lambsquarters, a summer annual weed, has occupied comparatively different ecogeographical regions around the globe. To investigate the extent to which germination and emergence traits have differentiated in two natural populations of common lambsquarters from different environments (Denmark as mesic and Iran as xeric population), experiments were conducted in the laboratory. Germination of both populations was stimulated by light. The greatest germination percentage of xeric and mesic populations occurred at 25/15 and 20/10 C, respectively. The xeric population showed significantly greater germinability at the lowest (15/5 C) and the highest (35/25 C) fluctuating temperature regimes. Germination of the xeric population was only slightly affected, and the mesic population was severely retarded at a salinity level of 20 desi siemens (DS) m-1. Greater than 42% of the xeric seeds germinated at 30 dS m-1 salinity, while the mesic germination almost ceased at this salinity level. Germination of seeds placed in distilled water after the 14-d salinity exposure treatments (recovery rates) was also greater for the xeric vs. mesic populations. Xeric populations showed more than 65% germination up to the osmotic potential of -0.4 MPa, while decreasing osmotic potential from 0 to -0.4 MPa caused an 80% reduction in mesic population germinability (9% germination). The greatest emergence of xeric (77%) and mesic (70%) populations occurred for seeds placed on the soil surface and no seedlings emerged from burial depth 3 cm. These study results suggest that common lambsquarters populations have differentiated for heat, salinity, and drought tolerance at germination stage. These contrasting germination patterns are appeared to be due to either adaptation via natural selection or maternal effects, or some combination of both. Though this study has certain limitations, it, through its findings and their propositions, adds to the existing knowledge about interpopulation differences in germination requirements of common lambsquarters, as a globally distributed species. © 2011 Weed Science Society of America. Source

Rakhshkhorshid M.,Birjand University
International Journal of Advanced Manufacturing Technology | Year: 2015

In this paper, a new simple model was developed based on a power function of Zener–Hollomon parameter and a third-order polynomial function of strainm (m is a constant) to model the hot flow stress of API X65 pipeline steel. The results of the developed equation for modeling the hot flow stress of API X65 pipeline steel was compared with two other constitutive equations, including the Arrhenius equation with strain-dependent constants and an equation with the peak stress, peak strain, and four constants. The performance of all three equations was compared with each other using a root-mean-square error (RMSE) criterion. According to the results obtained, the developed model showed better performance than that of the Arrhenius equation, but worse performance than that of the equation with the peak stress and peak strain. The simplicity of the proposed model is its advantage over the other considered constitutive equations. However, its performance is in an acceptable range. © 2014, Springer-Verlag London. Source

Zahiri S.-H.,Birjand University
International Journal of Machine Learning and Cybernetics | Year: 2012

Learning automata (LA) are adaptive decision making units that can learn to choose the optimal action from a set of actions by interaction with an environment (search space). This article proposes the use of the learning automata as a new tool for data mining (namely LA-miner). The basic scheme is utilizing LA as an effective optimizer for searching the rule-set space. In fact, LA-miner searches the rule-set space to discover an effective rule-set which maximizes a predefined fitness function. The fitness function is related to the total true positives, false positives, true negatives, and false negatives. Extensive experimental results on different kinds of benchmarks with nonlinear, overlapping class boundaries and different feature space dimensions are provided to show the powerfulness of the proposed method. The comparative results illustrate that the performance of the proposed LA-miner is comparable to, sometimes better than those of the CN2 (a traditional data mining method) and similar approaches which are designed based on the swarm intelligence algorithms (ant colony optimization and particle swarm optimization) and an evolutionary algorithm (genetic algorithm). © 2011 Springer-Verlag. Source

Nanofibrous hybrid yarns of polyvinyl alcohol (PVA) and poly-l-lactide acid (PLLA) with the antibacterial activity were prepared that contains 0, 5, 10, 20, and 30 wt.% of silver nanoparticles according to the PVA polymer content. This was performed by electrospinning using distilled water and 2, 2, 2-trifluoroethanol as a solvent for PVA and PLLA respectively, and sodium borohydride was used as a reducing agent. The scanning electron microscope observation confirmed the formation of AgNPs into the PVA nanofiber structure, and they were uniform, bead free, cylindrical and smooth. The diameter of hybrid yarns and their nanofiber component was decreased as the silver nitrate concentration in electrospinning solutions was increased. The differential scanning calorimetry results indicated that the silver nanoparticles can form interactions with polymer chains and decrease the melting enthalpy. The mechanical analysis showed a lower stress and strain at break of the AgNP-loaded nanofibrous hybrid yarns than the unloaded hybrid yarn. However, there wasn't a statistically significant difference between the strain at break of electrospun nanofibrous hybrid yarns. Moreover, the bactericidal efficiency of all loaded samples was over 99.99%. © 2014 Elsevier B.V. Source

The paper describes the study of the photocatalytic oxidation and antibacterial properties of cotton fabric treated with zinc oxide-silver (ZnO-Ag) nanocomposites. The ZnO nanoparticles were synthesized by an in situ approach on the surface of activated cotton fibers seeded with Ag nanoparticles. The effect of Ag nanoparticle-seeding and synthesis temperature on the morphological, thermal, photocatalytic and antibacterial properties of the ZnO-Ag nanocomposite-treated cotton fibers were characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffractometry, thermo gravimetric analysis, and Attenuated Total Reflection-Fourier Transform Infrared spectroscopy. Synthesizing ZnO nanoparticles on the surface of un-activated cotton fibers led to the formation of agglomerated nanoparticles while the Ag nanoparticle-seeded cotton fibers prevented this. The results indicated the presence of ZnO-Ag nanocomposites on the coated cotton fabrics, and all loaded samples presented an inhibition zone against S. aureus and E. coli bacteria. © the Partner Organisations 2014. Source

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