Assessment of genetic diversity in Triticum spp. and Aegilops spp. using AFLP markers

Genetic diversity among some wild relatives of wheat was estimated using amplified fragment length polymorphism (AFLP) and morphological markers. Thirty one Triticum and Aegilops genotypesincluding twenty-four Triticum and Aegilops accessions belonging to five diploid (Triticum baeoticum, Triticum monococcum, Aegilops umbellulata, Aegilops caudata and Aegilops tauschii), five tetraploid(Triticum dicoccoides, Triticum dicoccum, Aegilops crassa (4x), Aegilops cylindrica, Aegilops triuncialis) and two hexaploid (Triticum compactum, A. crassa (6x)) species sampled from different ecogeographical regions of Iran; a durum wheat cultivar 'Langdon', a local wheat cultivar 'Roshan', a wheat cultivar 'Chinese spring' and four synthetic hexaploid wheats were evaluated. Genetic diversity amongwheat accessions was estimated using 14 PstI:MseI primer pair combinations. Of the approximately 414 detected AFLP markers, 387 (93.5%) were polymorphic with 28 bands per used primer pair. Clusteranalysis of 31 accessions belonging to the 15 species by UPGMA cluster analysis based on Jaccard’s similarity estimates for AFLP data divided all accessions into two major clusters reflecting almost theirgenome composition. The first one included wheat species having A and AB genomes, while second cluster included wheat species having C, D, AB, CD, UC, DM, DDM and ABD genomes. The genetic similarity coefficients ranged from 0.12 between Ae. glabra and accession number 3 of T. monococcum and 0.57 between A. crassa (6x) and Ae. crassa (4x-6x). Two Aegilops species of A. umbellulata and A. caudata were ranked as the second most related species

The effects of exogenous proline and osmotic stress on morpho-biochemical parameters of strawberry callus

For evaluation of growth parameters of strawberry callus under osmotic stress and exogenous proline, embryonic calli were transferred to Murashige and Skoog (MS) medium containing four sucrose (osmotic stress) treatments including 3, 6, 9 and 12% and various concentrations of exogenous Lproline (0, 2.5, 5 and 10 mM) supplemented with 1 mg/l of 2,4-dichlorophenoxyacetic acid (2,4-D) + 0.5 mg/l 6-benzyl amino purine (BAP). After four weeks, various morpho-biochemical parameters of calliwere studied. Callus fresh and dry weight was strictly dependent on the concentration of sucrose in the medium. When the concentration of sucrose in the medium was increased from 3 to 9%, the amount of fresh weight was decreased, while dry weights increased in callus tissues. High concentration of sucrose (12%) caused the least content of fresh and dry weight in calli. When the concentration of sucrose in the medium was increased from 3 to 12%, the amount of free proline of callus was increased. Addition of exogenous proline to the culture medium improved the growth of calluses and intracellular free proline. The highest content of fresh weight (601.09 mg), dry weight (134.68 mg) and content ofproline accumulation (11.12 Moles/g fresh weight) were obtained in calli grown on media containing 10 mM proline, while the least content of fresh weight (297.62 mg), dry weight (49.55 mg) and free proline accumulation (0.817 Moles/g fresh weight) were observed in calli of control (without proline)

A new approach to solving multiorder time-fractional advection-diffusion-reaction equations using BEM and Chebyshev matrix

In this paper, the boundary element method is combined with Chebyshev operational matrix technique to solve two-dimensional multiorder time-fractional partial differential equations: nonlinear and linear in respect to spatial and temporal variables, respectively. Fractional derivatives are estimated by Caputo sense. Boundary element method is used to convert the main problem into a system of a multiorder fractional ordinary differential equation. Then, the produced system is approximated by Chebyshev operational matrix technique, and its condition number is analyzed. Accuracy and efficiency of the proposed hybrid scheme are demonstrated by solving three different types of two-dimensional time-fractional convection-diffusion equations numerically. The convergent rates are calculated for different meshing within the boundary element technique. Numerical results are given by graphs and tables for solutions and different type of error norms

Experimental Investigation of the Near Wake of a Pick-up Truck

The results of an experimental investigation of the flow over a pickup truck are presented. The main objectives of the study are to gain a better understanding of the flow structure in near wake region, and to obtain a detailed quantitative data set for validation of numerical simulations of this flow. Experiments were conducted at moderate Reynolds numbers (~3×105) in the open return tunnel at the University of Michigan. Measured quantities include: the mean pressure on the symmetry plane, unsteady pressure in the bed, and Particle Image Velocimetry (PIV) measurements of the flow in the near wake. The unsteady pressure results show that pressure fluctuations in the forward section of the bed are small and increase significantly at the edge of the tailgate. Pressure fluctuation spectra at the edge of the tailgate show a spectral peak at a Strouhal number of 0.07 and large energy content at very low frequency. The velocity field measurements in the symmetry plane show that shear layers form at the top of the cab and the underbody flow region. The cab shear layer evolves more slowly than the underbody flow shear layer and does not interact strongly with the tailgate for the present geometry. Behind the tailgate there is no recirculating flow region in the symmetry plane believed to be due to downwash from streamwise vorticity in the near wake. There are small recirculating regions on the sides of the tailgate symmetry plane extending approximately one tailgate height downstream