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A survey was carried out in five provinces of Iran (Kerman, Sistan and Baluchestan, Hormozgan, Khorasan and Yazd) for the presence of Alfalfa mosaic virus (AMV) sero-types in alfalfa during 2002 to 2003. The number of samples collected was 250, represent-ing the diversity and geographical distribution of AMV in these areas. Diagnosis was car-ried out using polyclonal (PAbs) and monoclonal (MAbs) antibodies. A total of 110 symp-tomatic leaf samples gave a positive reaction in ELISA with polyclonal antibodies. Twelve out of 20 MAbs reacted with all samples tested and were considered as non-differentiating MAbs. Only the MAbs-12, 13, 15, 21, 22 and 24 gave a clear differential reaction and were used for identifying AMV serotypes. Two MAbs (1 and 2) did not react with AMV posi-tive samples. Serological relatedness among AMV samples was studied by indicating the existence of six serotypes of AMV strains in the surveyed areas.

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Alfalfa crops were surveyed for the incidence of alfalfa mosaic virus (AMV), cucumber mosaic virus (CMV), peanut stunt virus (PSV), bean leaf roll virus (BLRV), bean yellow mosaic virus (BYMV) and bean common mosaic virus (BCMV) in the major growing areas in the southeast and central regions of Iran. Samples were collected between May 2009 and March 2011 and analyzed for viral infection initially by enzyme-linked immunosorbent assay (ELISA) followed by RT-PCR using capsid protein gene specific primers. In total, 634 symptomatic leaf samples were collected in four southeastern and central provinces of Iran representing 20 regions. Our results revealed a high incidence of AMV over a wide geographical area. AMV and BLRV were identified in most regions, whereas BYMV was found only in Yazd Province. PSV was detected in three regions, but not in Sistan- Balouchestan and Hormozgan Provinces. The highest incidence of viral infection amongst the surveyed provinces was recorded in Kerman (66.8%), followed by Yazd (39%), Sistan and Balouchestan (20.8 %), and Hormozgan (4.5%). AMV, BLRV, PSV and BYMV were present in 23.3%, 12%, 0.70% and 0.28% of the samples, respectively. CMV and BCMV were not detected in any surveyed region. Multiple virus infections were recorded in 42 samples. This is the first report on the detected occurrence of BLRV, PSV and BYMV in alfalfa in the southeast and central regions of Iran.

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In this study, forced convective heat transfer and pressure drop behavior of multi walled carbon nanotubes (CNT)-water nanofluid were evaluated under constant heat flux in a circular tube. For this purpose, first, homogeneous aqueous suspension of CNT using gum Arabic (GA) surfactant was prepared in concentrations 0.05%, 0.1% and 0.2% wt. Then, the above mentioned nanofluids were evaluated in Reynolds number range of 800-2000 under constant heat flux. The results indicate a significant increase in convective heat transfer coefficient of nanofluids with the addition of small amounts of CNT in deionized water. Also, heat transfer coefficient is enhanced with increasing concentration and Reynolds number. However, the effect of increasing concentrations of CNT is higher than the increase in Reynolds number. In addition, the pressure drop data on the different concentrations and Reynolds numbers are also investigated. At low weight concentrations of CNT, the deal of pressure drop of nanofluids containing CNT and base fluids is approximately similar and the gap between them is negligible. This means that no extra pump power is required for low concentration CNT/water nanofluid. The maximum increase in heat transfer coefficient is 42.8%, which occurred at Re=2027, and a concentration of 0.2% wt.