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1.
A number of methods of construction of partially balanced incomplete block designs with nested rows and columns are developed and new balanced incomplete block designs with nested rows and columns are obtained as a by-product. 相似文献
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Abstract A highly sensitive nested polymerase chain reaction method was designed for the detection of a wide spectrum of strains from Borrelia burgdorferi sensu lato. This technique allows the detection of as little as 3 fg of total genomic DNA extracted and purified from pure cultures of the organism, this amount corresponds to less than 10 organisms. Two sets of primers homologous to conserved spots in the coding region of the hbb gene, encoding a conserved histone-like protein, were constructed. These were based on a multiple sequence alignment of 39 strains representing all the genomic groups described in B. burgdorferi sensu lato. 相似文献
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This study aimed to test the concurrent validity of an electronic version (to run on tablet) of a sleep diary derived from the core Consensus Sleep Diary compared with the traditional paper and pencil version. To this end, 15 healthy volunteers (6 males; mean age 37.20 ± 17.55 years) every morning, for at least 7 consecutive days, filled both paper and electronic sleep diary. Furthermore, sleep was objectively assessed through actigraphy. With reference to all sleep parameters examined, no significant differences were observed between paper and electronic sleep diary. As expected, paper and electronic sleep diary showed the same poor agreement with actigraphic estimates of sleep quantity and sleep quality. On the basis of the present data, we can conclude that electronic sleep diary performs like paper sleep diary. Bearing in mind that electronic sleep diary presents several benefits in comparison to the paper sleep diary (e.g. avoiding of the “parking lot syndrome”, in which patient retrospectively completes more days at the same time; reducing the time for data entry and scoring), we suggest that, if the present findings will be confirmed also in clinical populations, electronic sleep diary should replace paper sleep diary in both research and clinical settings. 相似文献
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《Archives Of Phytopathology And Plant Protection》2012,45(13-14):1104-1111
AbstractThe economic importance of ornamentals has been advancing significantly in many countries due to continuous international demand. Like other crops, ornamental plants are also affected by a number of pathogens and the phytoplasmas diseases are equally important group of pathogens which is responsible for damaging the different ornamental plant species and thereby affecting their market value. In the present investigation, total 24 symptomatic leaf samples of 8 ornamental plant species (C. roseus, R. rubiginosa, C. variegatum, Z. elegans, J. gendurusa, T. erecta, H. rosa sinensis, J. sambrac) were analyzed which were found positive in nested PCR assays with R16F2n/R16R2 primers. The phytoplasma associated with ornamental plant species collected from different districts of UP in the present investigation are belongs to 16Sr I, II, VI and XIV group. 相似文献
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大豆油中转基因成分的Nested PCR和Semi-nested PCR检测方法研究 总被引:3,自引:0,他引:3
对大豆油中DNA提取方法进行了研究,结果表明CTAB、SDS和Wizard试剂盒提取大豆油DNA均具有良好的效果。利用nested PCR和semi—nested PCR检测大豆(Roundup Ready)油中的转基因成分发现,该方法能够检测到大豆原油中的Lectin基因(112bp)、CaMV35S基因(147bP)和CP4-EPSPS基因(205bp),检测灵敏度达到10^-6ng/μl;但该方法未能从人豆成品油(一级)中扩增到上述基因,当中的转基因成分DNA含量低于10^-12ng/μl。 相似文献
9.
Summary Xylanase from Scytalidium thermophilum was immobilized on Eudragit L-100, a pH sensitive copolymer of methacrylic acid and methyl methacrylate. The enzyme was non-covalently
immobilized and the system expressed 70% xylanase activity. The immobilized preparation had broader optimum temperature of
activity between 55 and 65 °C as compared to 65 °C in case of free enzyme and broader optimum pH between 6.0 and 7.0 as compared
to 6.5 in case of free enzyme. Immobilization increased the t1/2 of enzyme at 60 °C from 15 to 30 min with a stabilization factor of 2. The Km and Vmax values for the immobilized and free xylanase were 0.5% xylan and 0.89 μmol/ml/min and 0.35% xylan and 1.01 μmol/ml/min respectively. An Arrhenius plot showed an increased value of activation energy for immobilized xylanase (227 kcal/mol)
as compared to free xylanase (210 kcal/mol) confirming the higher temperature stability of the free enzyme. Enzymatic saccharification
of xylan was also improved by xylanase immobilization. 相似文献
10.
Enrique Núñez-Lara Pierre Legendre 《Journal of experimental marine biology and ecology》2005,324(2):157-169
Using a hierarchical multi-scale survey design, we examined the spatial patterns of reef fish communities and tested ecological models concerning the relative importance of reef geomorphology and anthropogenic pressure possibly driving community structure. Canonical redundancy analysis was used as a form of multivariate analysis of variance (MANOVA) to asses differences in reef fish community composition at two spatial scales: broad (105 m) and intermediate (104 m). Surveys were conducted on the east coast of the Yucatan Peninsula (Mexican Caribbean fringing reef), including regions and reefs which differed in geomophologic structure and human use. Seven hundred and fourteen line transects were distributed among 13 reef localities belonging to different regions established a priori. Transects covered four types of reef habitat: lagoon, front, slope, and terrace. Tests of significance were based on permutation procedures. Significant differences among regions were found for the lagoon, slope, and terrace fish communities, consistent with the geomorphologic model, but it is only in the reef lagoon that they were consistent with the anthropogenic model, which may indicate an effect of coastal human activities. Significant differences among reefs within regions were observed, which could be associated with local environmental gradients. Canonical nested MANOVA was an appropriate method for testing ecological hypotheses about the functioning of complex biological systems. The use of a surveying strategy that explicitly incorporated the spatial structure represents an important contribution of this paper to coral reef fish ecology. 相似文献