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71.
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The prevalence of intramammary infection in 4 commercial goat herds was studied in conjunction with electronic somatic cell count and volume analysis determined using a Coutler Counter and volume analyser. Neither streptococci nor mycoplasma were isolated from any half and the prevalence of intramammary infection with Staphylococcus aureus ranged from 0 to 3% between herds. For coagulase-negative staphylococci the range from infected halves was 36-71%. There was no significant difference between the mean total microscopic somatic cell count for halves infected with coagulase-negative staphylococci and those free from infection. A similar trend was observed for electronic somatic cell counts although the mean electronic cell count was greater than the mean total microscopic count on the 2 occasions that they were compared. The correlation coefficients between the 2 cell counting methods were 0.86 and 0.94. Between herds there were significant differences in mean electronic somatic cell count, with herd means ranging from 438 x 103 to 1684 x 103 cells/ml. In 2 of the 4 herds studied, milk samples from halves infected with coagulase-negative staphylococci had a significantly higher prevalence of cell volume distributions with a modal cell volume between 65 mu 3 and 100 mu 3. This was attributed to a higher proportion of polymorphonuclear neutrophils. Use of electronic somatic cell count and cell volume analysis were considered of little value in predicting infection caused by coagulase-negative staphylococci as there was a high proportion of false negative and false positive predictions. 相似文献
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The structural features of undoped CdTe ingots grown in a gasdynamic flow at 620°C were studied by selective etching and X-ray
diffractometry. It is found that the samples grown at a deposition rate of up to 500 μm/h consist of independently growing
rods with both [111] A and [111] B directions. This indicates that the vapor composition in the growth region is almost stoichiometric. Both rod types exhibited
transverse striations due to rotation twins. The twin boundaries in rods with the growth direction [111] A were shown to be also small-angle boundaries with additional misorientation of separate twins of 0.2°–0.3°.
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Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 37, No. 2, 2003, pp. 129–133.
Original Russian Text Copyright ? 2003 by Klevkov, Martovitskii, Medvedev. 相似文献
77.
Sergii I. Shylin Vadim Ksenofontov Sergey A. Medvedev Claudia Felser 《Journal of Superconductivity and Novel Magnetism》2016,29(3):573-576
Although pairing mechanism in unconventional superconductors is still an open question, the density of states at the Fermi level is considered to be one of the factors affecting the superconducting transition temperature. Herein, we report on 57Fe-Mössbauer studies of β-FeSe, FeSe 0.5Te 0.5, and Rb 0.8Fe 1.6Se 2 superconductors as well as two intercalate products consisting of FeSe layers and a lithium-containing molecular spacer in between. In these materials, the hyperfine parameters of 57Fe are directly related to the 3d-electron density on Fe atoms and show strong correlation with superconducting properties. 相似文献
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E. F. Medvedev 《Glass and Ceramics》1998,55(1-2):28-30
Glass with an aventurine effect in the lead-boron-silicate system has been developed using metallurgical slag. The experimental results are processed based on probability theory and random process methods. A mathematical model of the charge is developed. The role of the slag in the process of glass synthesis is determined. 相似文献