The activated c-Ha-ras oncogene induced AP1-site DNA-binding activity in F9 cells. This induction appeared to be due, at least in part, to the induction of c-jun transcription. Both activated c-Ha-ras and c-jun induce...
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The activated c-Ha-ras oncogene induced AP1-site DNA-binding activity in F9 cells. This induction appeared to be due, at least in part, to the induction of c-jun transcription. Both activated c-Ha-ras and c-jun induced the differentiation of F9 cells to endoderm-like cells. Thus, AP1 appears to play a key role in the initial stage of F9 cell differentiation.
Despite the great attention lavished on science and technology by a diversity of academic disciplines and specialties, surprisingly little is known about the pre-eminent vectors for scientific knowledge and the foremo...
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Despite the great attention lavished on science and technology by a diversity of academic disciplines and specialties, surprisingly little is known about the pre-eminent vectors for scientific knowledge and the foremost practitioners of technology - ordinary engineers. Elite (and therefore, by definition, unrepresentative) cases aside, what is known about engineers normally concerns either their aggregate numbers and gross levels of education, or their professional societies. The inquiry described here seeks to depict in somewhat richer detail one engineering discipline - petroleum engineering - and to examine in a general way how that discipline fits into the particular society of which it was a part. The point is simply that, far from being the on-dimensional 'nerds' of stereotype, engineers are multidimensional social entities - and that, in constructing their roles in social action, who they are very likely matters every bit as much as what they know. [ABSTRACT FROM AUTHOR]
Reproducible and discriminating typing methods are required for epidemiological investigations. Numerical typing systems analyse patterns obtained in various ways by calculating similarity coefficients between isolate...
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Reproducible and discriminating typing methods are required for epidemiological investigations. Numerical typing systems analyse patterns obtained in various ways by calculating similarity coefficients between isolates. In the present study, various measures of the efficiency of a numerical typing system are quantified. These include reproducibility, accuracy, and discrimination power. Three different numerical typing methods for Escherichia coli were compared using these measures: (a) Biotyping with API 50 CH system, (b) Biochemical fingerprinting with the API 50 CH system and (c) Biochemical fingerprinting with the PhP-EC system. Biotyping qualitatively measures the results of a set of biochemical reactions as + or -. Biochemical fingerprinting also uses biochemical reactions, but the tests are scored quantitatively by measuring the kinetics and intensity of each reaction. It was found that biotyping yielded poor reproducibility. When biochemical fingerprinting analysis was used with the API 50 CHE system the reproducibility and the discrimination was good. The PhP-EC system for biochemical fingerprinting showed equal reproducibility but was superior to the API 50 CH system with regard to discrimination power.
The host specificity of yeast-yeast interactions was investigated for two yeast types, represented by six pairs of Pichia membranifaciens clade yeasts (Pichia membranifaciens or Issatchenkia occidentalis) with apicula...
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The host specificity of yeast-yeast interactions was investigated for two yeast types, represented by six pairs of Pichia membranifaciens clade yeasts (Pichia membranifaciens or Issatchenkia occidentalis) with apiculate yeasts (Kloeckera apis, Kloeckera africana, or Saccharomycodes ludwigii), commonly found in fruits. Competitive interactions between the two types were detected in both ripe tomato and guava. fruit pulp. The differences in growth rates and carrying capacities depended on fruit type (host) and culture conditions (monocultures versus bicultures). These differences were probably due to nutrient composition of each fruit. Pichia membranifaciens did not show host dependent responses, but the apiculate yeasts and Issatchenkia occidentalis did. Depending on yeast strain and culture conditions (i.e., monoculture or biculture), carbon, nitrogen, and vitamins were investigated as potential limiting growth factors in guava fruit. Both singular and multiple limiting nutrients were implicated.
To determine the utility of availablePseudomonas cepaciatyping systems for confirming the relatedness of isolates, we applied these methods to isolates associated with previously investigated nosocomial outbreaks. We ...
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To determine the utility of availablePseudomonas cepaciatyping systems for confirming the relatedness of isolates, we applied these methods to isolates associated with previously investigated nosocomial outbreaks. We compared chromosome analysis, serologic reactions, biochemical tests, bacteriocin production and susceptibility, and antimicrobial susceptibility in their ability to determine outbreak relatedness. Chromosome analysis, serologic reactions, and biochemical tests were each demonstrated to be epidemiologically useful methods for typing isolates. Determination of the sensitivity and specificity of these typing techniques will facilitate their application in the epidemiologic study of this increasingly important nosocomial pathogen.
Sex-limited alleles may be of importance for the genetic variability of the Hymenoptera. A coefficient for sex limitation is formulated;such a coefficient indicates that about 14% of the detrimental alleles in Apis me...
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Sex-limited alleles may be of importance for the genetic variability of the Hymenoptera. A coefficient for sex limitation is formulated;such a coefficient indicates that about 14% of the detrimental alleles in Apis mellifera are limited to females.
Bacterial strains were randomly isolated from soil using three different media with glucose (TG), Tryptone Soya Broth (TTS) and succinate (TC) as carbon sources. Plate counts obtained were 12.0 .times. 107, 4.5 .times...
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Bacterial strains were randomly isolated from soil using three different media with glucose (TG), Tryptone Soya Broth (TTS) and succinate (TC) as carbon sources. Plate counts obtained were 12.0 .times. 107, 4.5 .times. 107, and 1.5 .times. 107 g-1 soil dry weight, respectively. The strains were characterized phenotypically by the API 20B test system. A cluster analysis of all isolates revealed 40 biotypes at 80% similarity, 23 in TG, 29 in TTS, and 27 in TS. Each of the 10 most common biotypes contained 10 to 2.5% of the isolates, and 17 biotypes contained one or two isolates. The common biotypes were unevenly distributed among the isolates from the different media. About 20% of the isolates from TG and TTS were unique for the particular medium, whereas among the isolates from TS, about 60% were unique. Thirty percent of the isolates belonged to biotypes that were common to all three populations. All media gave approximately the same high diversity measured as Shannon index and Equitability, indicating no direct correlation between plate count and diversity.
The choice between using the functionality of the application's platform (Java EE or .NET), calling one of several available external libraries, or writing code on your own involves numerous factors. When you writ...
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The choice between using the functionality of the application's platform (Java EE or .NET), calling one of several available external libraries, or writing code on your own involves numerous factors. When you write your own code, you control its quality. If some alternatives come in the form of external libraries, start by looking at the licensing terms. Next, judge the usability of the library or the platform API and the library's compatibility with your system. Elements with diverse naming conventions are an open invitation for disorder and style abuses. Other compatibility areas you should investigate include error handling, memory management, multithreading, and build management. Finish your examination by looking into the library's dependencies, quality, and support.
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