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Background: Mupirocin is a topical antibiotic inhibiting most Gram-positive cocci. Shortly after taking mupirocin, drug resistance emerges. This study aimed to determine mupirocin resistance in Staphylococcus aureus strains isolated from clinical specimens in Rasht.
Materials & Methods: In this study, a total of 85 clinical isolates of S. aureus were collected. Biofilm formation ability and antibacterial resistance patterns of isolates were investigated. Disc diffusion method and MIC determination were used to determine the susceptibility of strains to mupirocin antibiotic. Agr types, the presence of mupA, and mutation in ileS-1 were evaluated in mupirocin non-susceptible isolates by PCR and PCR sequencing, respectively.
Findings: Out of 85 tested strains, 57 (67%) isolates were recognized as biofilm producers, and all of which showed multidrug resistance phenotype. Agr type 1 was the most commonly detected type. Additionally, 12 mupirocin-resistant strains were identified in the disc diffusion and MIC tests. A total of four strains were mup-A positive and showed high-level resistance. In sequencing and mutation evaluation of the ileS-1 gene in eight low-level mupirocin-resistant strains, 12 types of silent mutation and one type of missense mutation were determined.
Conclusion: The study of mupirocin-resistant strains in this study showed the need to identify factors affecting the occurrence of resistance and to take control and prevention measures before mupirocin losses its efficacy.

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In this research We introduce a new distribution center (DC) location model that incorporates working inventory and safety stock inventory costs at the distribution centers. In addition, the model incorporates transport costs from the suppliers to the DCs that explicitly reflect economies of scale through the use of a fixed cost term. The model was formulated as a non-linear integer-programming problem. The algorithms were tested on the problems with 15 retailers and 5 distribution centers. We uses SOLVER of Excel for modeling, solution and sensitivity analysis of the results. Finally, the sensitivity of the results to changes in key parameters including the fixed cost of placing orders was discussed. Significant reductions in these costs might be expected from e-commerce technologies. The model suggests that as these costs decrease, it is optimal to locate additional facilities.

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One of the most important permanence factors in today’s competition environment is decreasing of the cost of the products. Selecting the appropriate suppliers can significantly reduce the purchasing cost and increase organization competitiveness. It is due to the fact that in most industries, the cost of raw material and component parts includes the main cost of a product. The aim of this paper was to introduce a fuzzy decision making approach for supplier selection problems in supply chain. Most of such decisions are unstructured and many of the performance criteria such as quality, cost, flexibility and delivery time to determine the best supplier should be considered. In this paper, verbal variables were used for evaluation and determination of the performance of supplier under each criterion and determination of the weight of the criteria. Verbal variables were described by means of the triangular and trapezoid fuzzy numbers. Furthermore, the priority and the rank of suppliers by fuzzy multi-criteria decision making were determined. Finally, an example was presented to the process of decision making.