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61.
62.
A microprocessor-based device is described for measuring sinusoidal variations of the magnetization and specific loss curves in electric steel samples in conformity with GOST 12119-80. The method of functional sampling, on which the tester operation is based, is described, the design of the measuring channels is discussed, and the tester's metrological characteristics are analyzed. Translated from Izmeritel'nayka Tekhnika, No. 5, pp. 51–54, May, 1995.  相似文献   
63.
The automated system is designed to measure the magnetic characteristics and parameters of electrical-engineering steels and other soft magnetic materials when they are subjected to alternating magnetization in the 20–5120 Hz frequency band. The system is controlled by an IBM PC/AT personal computer, has high metrological characteristics, and the subsystems perform the junctions of diagnostics, graphical presentation, statistical processing and archiving of the results of measurements.Translated from Izmeritel'naya Tekhnika, No. 12, pp. 42–45, December, 1993.  相似文献   
64.
The objectives of the investigation were to provide information on the concentration and distribution of metals in bottom sediments of the Detroit River and to study the association of metals with various sediment components. Concentrations of major elements (Si, Al, Ca, Mg, Na, K, Fe, Mn, and P) and metals (Co, Cr, Cu, Ni, Pb, and Zn), particle size distribution, and mineralogical composition were determined in 20 surficial sediment samples collected along the Detroit River in 1983. Significantly higher concentrations of metals in the Detroit River sediments than those reported in Lake St. Clair and Lake Erie sediments indicated input from sources in the river's drainage basin. Poor relationships exist between the metals and organic C and the metals and the silt-clay size fraction (< 63 μm). The association of metals with sediment particles was investigated by a separation of sediment into seven size fractions ranging from < 13 to > 63 μm. Zn, Ni, Cr, and Pb were accumulated in the < 13 μm size fraction. However, Cu and Cr concentrations were highest in the < 13 and 48 to 63 μm fractions. Quartz, feldspars, and calcite were found in the > 63 μm fraction. Dolomite, feldspars, and quartz were in the 13 to 63 μm fraction and the clay minerals illite, chlorite, and kaolinite were in the < 13 μm fraction. Concentrations and relationships among major elements reflected the mineralogical composition of different particle size fractions.  相似文献   
65.
66.
The meaning of the term the intellectual island effect which was introduced byArunachalam et al. is broadened as to characterize the status of science on the periphery in general. A practical solution is proposed, based on bibliometric data of the research output and relying on two criteria: the extent of coverage by world significant secondary literature and the extent of scatter of that literature. Reliability of the publication data retrieved from the Citation Indexes is discussed; a measure is offered to assess the adequacy of the Citation Indexes as the data sources.Unquestionably, there has been no one like Einstein in physics in this century, but one has to reflect on how easily Einstein might have been lost, particularly if he had been born in a developing country.From C. M. KINNON, (Ed.)The Impact of Modern Scientific Ideas on Society Reidel/UNESCO, 1981, p. 29.  相似文献   
67.

Definition of the problem

Ethical aspects of biobanking research are receiving increasing attention in the literature. It is particularly controversial which model of consent should be implemented in research biobanks.

Arguments

This paper outlines the ethical controversy surrounding various models of consent into biobank-based research. Following a brief introduction of established consent models, it delineates the development of alternative approaches and discusses the ethical and regulatory challenges associated with these. Relevant ethical principles are highlighted.

Conclusion

The article concludes that there are good reasons to trial a combination of initial broad consent with consent to governance for future biobanking research in Germany.
  相似文献   
68.
Semicontinuous emulsion polymerization of acrylic monomers with a monomer emulsion feed has been investigated. The amount of coagulum appearing during the polymerization under conditions of insufficient covering of particle surface by emulsifier was studied from the point of view of particle surface charge. Increasing the surface group concentration via copolymerization of butyl acrylate with acrylic acid or sulfoethyl methacrylate caused increased colloid stability of the system and a rapid decrease in coagulum formation. It was established that during the polymerization acid hydrolysis of ester groups took place, which caused an increase in the carboxyl groups concentration at the particle surface. These carboxyl groups contribute to the colloid stability of the polymerizing system.  相似文献   
69.
In this study, several different depolymerases encoded in the prophage regions of Acinetobacter baumannii genomes have been bioinformatically predicted and recombinantly produced. The identified depolymerases possessed multi-domain structures and were identical or closely homologous to various proteins encoded in other A. baumannii genomes. This means that prophage-derived depolymerases are widespread, and different bacterial genomes can be the source of proteins with polysaccharide-degrading activities. For two depolymerases, the specificity to capsular polysaccharides (CPSs) of A. baumannii belonging to K1 and K92 capsular types (K types) was determined. The data obtained showed that the prophage-derived depolymerases were glycosidases that cleaved the A. baumannii CPSs by the hydrolytic mechanism to yield monomers and oligomers of the K units. The recombinant proteins with established enzymatic activity significantly reduced the mortality of Galleria mellonella larvae infected with A. baumannii of K1 and K92 capsular types. Therefore, these enzymes can be considered as suitable candidates for the development of new antibacterials against corresponding A. baumannii K types.  相似文献   
70.
Early and reliable markers of acute kidney injury (AKI) are essential. One such candidate marker of tissue damage is extracellular DNA (ecDNA). The aim of our present study is to describe the unknown dynamics of ecDNA in an animal model of AKI. Glycerol-induced nephropathy was used to model AKI in adult male Wistar rats (n = 93). Blood and urine samples were collected 1, 3, and 24 h after model induction. Total ecDNA and its sub-cellular origin was assessed. In the plasma, total ecDNA and nuclear ecDNA were significantly increased in the AKI group already after 1 h (160% and 270%, respectively, p = 0.02 and p = 0.04). Both nuclear and mitochondrial ecDNA were higher after 3 h (180% and 170%, respectively, p = 0.002 and p = 0.005). Urinary ecDNA concentrations in the AKI group were significantly increased only 24 h after model induction (130% for total ecDNA, p = 0.009; 210% for nuclear ecDNA, p = 0.02; and 200% for mitochondrial ecDNA, p = 0.0009). Our results indicate that plasma ecDNA has the potential to serve as an early and sensitive, albeit non-specific marker of AKI. Further studies should elucidate the source of ecDNA and the dynamics of ecDNA in other animal models of AKI and patients with AKI.  相似文献   
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