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Cercospora leaf spot caused by Cercospora beticola has a great negative impact on yield and quality of sugar beet. In the present study, pathogenic and genotypic variation of 24 C. beticola isolates collected from different regions of Iran were studied using RFLP of the Internal Transcribed Spacer (ITS-RFLP), and Random Amplified Polymorphic DNA (RAPD-PCR). Pathogenic variability and genotype × isolate interaction were evaluated in greenhouse experiments on five sugar beet cultivars (FD0018, HM1836, Puma, Eudora and Monatuna). All of the 24 isolates tested were found to be pathogenic on the cultivars with significant variation in disease severity. Results of RAPD analysis showed wide DNA polymorphism among the Iranian C. beticola isolates. Restriction pattern of the internal transcribed spacer of rDNA (ITS1-5.8-ITS4) was studied using three restriction endonucleases: EcoR1, Taq1, and Busr1. The length of undigested DNA fragment of all isolates was estimated to be 500bp without rDNA polymorphism after digestion with EcoR1 (280, 270 bp), Taq1 (330 bp) and Busr1 (240, 220, 90 bp). RAPD and ITS-RFLP markers showed the highest level of genetic diversity which confirms the variation in C. beticola detection.

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Klebsiella pneumoniae is a gram-negative bacillus of the Enterobacteriaceae family. Despite being part of the natural human microflora, this is an opportunistic pathogen and a major cause of nosocomial infections. The increased emergence of multidrug resistance in Klebsiella pneumoniae has limited the treatment options for this bacterium. Carbon nanotubes (CNT), by improving the stability and solubulity of drugs, could increase the effectiveness of drugs for treatment. The aim of this study is to investigate the antibacterial effect of nanofluid containing functionalized multi-walled carbon nanotubes (f-CNT-NF) on Klebsiella pneumoniae isolated from clinical specimens. For the strain confirmation, biochemical ,API20E kit, and additional differential tests were performed, and antibiotic susceptibility test was performed by the disk diffusion method. The studied strain showed a resistance to all antibiotics such as cefepime.The minimum inhibitory concentration (MIC) was determined using the antibiotic micro dilution method. The MIC was determined in five effect modes including antibiotic (Ab), nanofluid containing functionalized multi-walled carbon nanotubes (f-CNT-NF) , nanofluid containing multi-walled carbon nanotubes (CNT-NF) ,Ab in combination with f-CNT-NF and Ab with CNT-NF. Nevertheless the individual effects of 10 µg mL^-1 cefepime or 80 µg of nanofluid with f-CNT-NF did not inhibit the growth of the bacteria, but the co-administration of 10 µg mL^-1 cefepime with 80 µg of the f-CNT-NF could inhibit the bacteria`s growth. It was concluded that f-CNT-NF could be more effective in drug delivery at lower concentrations than the free state, which could be used as a tool for optimal drug delivery.

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Application of vertical air curtain refrigerators in commercial stores has gained popularity due to easy access of products by the customers. However, energy consumption of these refrigerators is approximately %50 higher than that of refrigerators with doors. This paper experimentally investigates the effect of ambient temperature variation on the performance of these refrigerators. Experimental measurements include parameters such as temperature, pressure, relative humidity, velocity, and power consumption in both air cycle and refrigeration cycle. Moreover, parameters such as compressor power, refrigeration effect, total load, coefficient of performance, pressure ratio, thermal entrainment coefficient, refrigeration capacity, volumetric and mass flow rates of air in the evaporator and condenser, refrigerant mass flow rate, condenser heat, air curtain thermal efficiency, Richardson number, Reynolds number, and deviation modulus under different ambient conditions were calculated. The experimental results show that the refrigeration performance is affected by ambient air temperature, which directly influence on the infiltration rate of ambient air into the refrigerator compartment and on the return air temperature to the evaporator. Therefore, the return air temperature is crucial indicator for assessing the efficiency of the refrigerator. With increasing ambient temperature, compressor power increases, while the refrigeration effect and COP decrease. The results also indicate that as ambient temperature rises, air curtain efficiency decreases somehow that temperature difference between front and rear of the shelves may reach up to 4.6°C. For every 1°C increase in ambient temperature, compressor power consumption increases by approximately %0.64, while refrigeration effect and COP decrease by %0.06 and %1.77, respectively