Magdi Mohamed Mashly

ABSTRACT This study aimed at elucidating the genetic variation within and between duck populations and estimating the phylogenetic relationships among them. Five duck breeds of two species, Muscovy and Sudani of Cairina species, and White Pekin, Damietti and Khaki Campbell of Anas species, were used. The technique of random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) was applied using five random primers. Individual DNA samples within breed and also a bulk of DNA samples for each breed were used. Primers amplified bands with an overall mean of 8.45 and 8.68 bands for individual and pooled samples, respectively. No significant difference was observed between pooled and individual samples indicating the reliability of mixing DNA samples within breed. High levels of polymorphism and heterozygosity between breeds were obtained. Two primers (OPC-08 and OPC-11), resulted in highly polymorphic markers for duck genomes. Specific bands were obtained for species and also for breeds. The overall mean of genetic variability indices within breed was low to moderate and averaged 0.38, whereas band sharing levels within breed were high and averaged 0.73. Variability estimates between breeds were 0.47 and 0.35 for individual and pooled samples respectively, whereas band sharing estimates were 0.63 and 0.74. Genetic distance indices between breeds ranged between 0.264 and 0.728.

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The observation of longitudinal momentum distribution (P ||) from two-neutron removal in 19C with a Be target at 64 A MeV is reported. Analysis in terms of Glauber model considering 19Cgs( J π = 1/2+) shows that neutron evaporation is necessary to explain the data.

Nickel impregnated zeolite-modified electrodes were prepared by mixing Ni–silicalite-1 with conducting carbon black in different rations. Using the cyclic voltammetric technique the electrochemical oxidation of methanol at such electrodes was investigated. Experiments on silicalite-1 (S-1) and nickel–silicalite-1 (Ni–S-1) show that they are not electrochemically active towards methanol oxidation in KOH solution. The presence of nickel ions in the zeolite matrix, by soaking the electrode in an aqueous NiSO4 solution, markedly enhances the electro-catalytic activity which was found to depend on the nickel content. On the other hand, the presence of zeolite and/or Ni metals in the catalyst is essential, however, the electro-catalytic activity depends on the Ni–S-1:carbon black ratio. Electrodes with Ni–S-1:carbon black ratio of 1:3, show the maximum electro-catalytic activity. The importance of impregnated Ni metal in the zeolite matrix is discussed on the basis of the experimental results. A weak dependence on bulk methanol concentration was observed. SEM analysis was used to characterize the Ni–S-1 catalyst. Dependence of methanol electro-oxidation on methanol concentration was discussed.