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Azole-resistant Aspergillus fumigatus (AR Af), reported as a global public health concern, has been unexpectedly observed in different countries. To identify AR Af and detect azole resistance related to the CYP51A mutation in different hospital environmental samples. In this multi-centre study from Iran, surfaces of electronic equipment and appliances from different hospitals in Iran were sampled using cotton swabs. All samples were cultured using azole-containing agar plates (ACAPs). Recovered Aspergillus isolates were identified at the species level using partial DNA sequencing of the β-tubulin gene. The azole susceptibility testing of A. fumigatus isolates was performed using the Clinical and Laboratory Standards Institute M38-A3 guideline. The sequencing of the CYP51A gene was also performed to detect mutations related to resistance. Out of the 693 collected samples, 89 (12.8%) Aspergillus species were recovered from ACAPs. Aspergillus fumigatus (41.6%) was the most prevalent, followed by A. tubingensis (23.6%) and A. niger (15.6%). Among 37 isolates of A. fumigatus , 19 (51.3%) showed high minimum inhibitory concentration (MIC) values to at least one of the three azoles, voriconazole, itraconazole, and posaconazole. CYP51A polymorphisms were detected in all 19 isolates, of which 52.6% showed the TR 34 /L98H mutation. Other detected mutations were G432C, G448S, G54E/G138C, F46Y, and Y121F/M220I/D255E. T289F and G432C were the first reported mutations in AR Af. There was a considerable level of azole resistance in hospital environmental samples, a serious warning for patients vulnerable to aspergillosis. Our findings have also revealed a different mutation pattern in the CYP51A gene. [ABSTRACT FROM AUTHOR]

Abstract: During the past few years, many people have been interested in integrated production and marketing planning strategies where demand and cost functions, both, depend on different parameters such as price and marketing expenditure. The primary concern on all previous models is the difficulty on estimating the model parameters such price and marketing elasticity to demand. In this paper, we propose a new possibilistic model which makes it easy to build the overall model based on experts’ opinions. The proposed model is formulated in fuzzy geometric programming and the fuzzy decision is made using the recent advances on optimization techniques. We also design a fuzzy logic controller to facilitate the decision making process. The implementation of the proposed model is demonstrated using two numerical examples. [Copyright &y& Elsevier]

Abstract: Fuzzy Cognitive Map (FCM) is a directed graph, which shows the relations between essential components in complex systems. It is a very convenient, simple, and powerful tool, which is used in numerous areas of application. Experts who are familiar with the system components and their relations can generate a related FCM. There is a big gap when human experts cannot produce FCM or even there is no expert to produce the related FCM. Therefore, a new mechanism must be used to bridge this gap. In this paper, a novel learning method is proposed to construct FCM by using some metaheuristic methods such as genetic algorithm (GA) and simulated annealing (SA). The proposed method not only is able to construct FCM graph topology but also is able to extract the weight of the edges from input historical data. The efficiency of the proposed method is shown via comparison of its results of some numerical examples with those of some other methods. [Copyright &y& Elsevier]

Abstract: This paper studies an application of hybrid systematic design in multiobjective market problems. The target problem is suggested as unstructured real world problem such that the objectives cannot be expressed mathematically and only a set of historical data is utilized. Obviously, traditional methods and even meta-heuristic methods are broken in such cases. Instead, a systematic design using the hybrid of intelligent systems, particularly fuzzy rule base and neural networks can guide the decision maker towards noninferior solutions. The system does not stay in search phase. It also supports the decision maker in selection phase (after the search) to analyze various noninferior points and select the best ones based on the desired goal levels. In addition, numerical examples of real crude oil markets are provided to clarify the accuracy and performance of the developed system. [Copyright &y& Elsevier]

Abstract: Some size-dependent characteristics of FeCo nanoparticles are investigated in this paper. The nanoparticles are fabricated using a coprecipitation route and their sizes are controlled by changing the reaction time. Transverse electron microscopy (TEM) images show that the nanoparticles are all spherical with an average size of 2–6 nm. The average size obtained from X-ray diffraction (XRD) measurements is in the range 1–3 nm. Magnetic measurements reveal that the nanoparticles are ordered ferromagnetically and have a high coercivity of about 500 Oe. In our measurements, the coercivity was decreased with decreasing particle size, indicating that the nanoparticles were in a single-domain region. Production of FeCo nanoparticles with high coercivity and fine dimension is highly promising for future recording media technology. [Copyright &y& Elsevier]