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1.
Data on allelic polymorphism of MET and D7S23 DNA loci linked to the human cystic fibrosis gene studied in three Bashkir ethnic groups and some Volga-Ural populations (Tartars, Maris, Mordovians, Udmurts, Chuvashs, and Komis) are presented. Udmurts were found to be substantially different from Bashkirs, Tartars, Mordovians, and Chuvashs by the allele frequency distribution observed for MET, while Komis and Bashkirs differed by this parameter from Mordovians and Maris. Comparative analysis of restriction fragment length polymorphism (RFLP) at the D7S23 locus revealed statistically significant differences in genotype frequencies between Bashkirs of the Arkhangel' skii region and populations of Mordva and Udmurtia. In this respect, the Mordovian population appeared to be notably different from the populations of Bashkortostan, Tatarstan, Marii-El, Udmurtiya, Chuvashiya, and Komis. Genetic distances were calculated and corresponding dendrograms were constructed on the basis of data on Met-H, CS.7, and the ApoB locus hypervariable region allelic frequencies. Three ethnogeographic Bashkir groups belonging to one tree branch were found to be closely related to the populations of Tartars, Maris, Udmurts, and Chuvashs and substantially different from Komis and Mordovians. Thus, the position of Volga-Ural populations on the dendrogram corresponds to the degree of relationship between the Finno-Ugric and Turkic populations, confirming the usefulness of DNA polymorphism analysis for the study of the genetic structure of populations.  相似文献   
2.
We measured the coefficients of diffusion of hydrogen in the hydride phases of hafnium and titanium at 1073–1273°K on the basis of the solutions of Fick's second law for diffusion in a finite cylinder and in a sector of it.Notation Co initial concentration of gas in the metal, ncm3/cm Me 3 - C(r,, z, t) instantaneous gas concentration in the finite cylinder - i, k, m, n ordinal numbers (indices) - Jn(n ir/R) Bessel function of order n - n i i-th root of the Bessel function of order n - R,l radius and thickness of the specimen, cm - D diffusion coefficient, cm2/sec - t time, sec - V calibrated volume above specimen, cm3 - F admittance of gas pumping channels, ncm3/sec - dQre1/dt rate of gas release, ncm3/sec - p pressure of released gas, torr - dp/dt change in released-gas pressure per unit time, torr/sec - tan tangent of the angle of inclination of the straight line in equation (6), 1/sec - IH2 ion current of hydrogen - (n) gamma function - W coefficient of variation, % - mean-square deviation - Do preexponent, cm2/sec - E activation energy, kJ/mole - T absolute temperature of specimens - B universal gas constant, kJ/ deg·mole Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 39, No. 4, pp. 643–648, October, 1980.  相似文献   
3.
In this work we extend the approach used in [6] to perform distributed-memory AFMC model checking. The part of a system held in one computer is modeled as a Kripke structure with border states. Moreover, we use assumptions about the truth of a formula in each state. Each process then repeatedly executes a slight modification of a standard sequential algorithm and exchanges its results with other processes. In the paper we define the AFMC semantics for structures with border states and assumptions, present the distributed algorithm and show the main ideas behind the proof of its correctness. Complexity and experimental results are provided as well.  相似文献   
4.
This investigation explores the use of five‐parameter logistic curve fitting in quantifying turbidity robustness and risk scoring in clarification and filtrations stages of several surface water treatment works in the Anglian Water region of the United Kingdom. The approach taken reviews different scoring systems and addresses issues of weighting, averages and variability in robustness performance using turbidity robustness indices (TRIs). It also proposes an area‐based risk scoring profile to assess performance [relative area profile for T90 (RAP90)]. The metrics produced are considered to be a logical and rational way to help prioritise where resources for water treatment operation should be deployed.  相似文献   
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ABSTRACT

The paper deals with a study of tensile strength and disintegration time of compacts made from silicified microcrystalline celluloses, Prosolv SMCC 90, and Prosolv HD 90, in dependence on compression force, addition of two types of lubricants, and two active ingredients. The lubricants were magnesium stearate and sodium stearyl fumarate in a concentration of 0.5%, the active ingredients being ascorbic acid and acetylsalicylic acid in a concentration of 50%.

Prosolv SMCC 90 proved to be better compatible than Prosolv HD 90; the compacts were of higher strength, which was markedly increased with increasing compression force. Prosolv HD 90 was more sensitive to additions of lubricants, and a greater decrease in strength was recorded due to the influence of sodium stearyl fumarate. The effect of lubricants on the strength of compacts in the presence of active ingredients was not identical. The disintegration time of compacts from Prosolv HD 90 without as well as with lubricants was shorter than from Prosolv SMCC 90 and was increasing with increasing compression force. Disintegration time was increased with added lubricants, and it was markedly shortened by addition of active ingredients. Compacts containing ascorbic acid possessed a shorter disintegration time than those containing acetylsalicylic acid, and it was not markedly influenced by the presence of lubricants.  相似文献   
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High pressure high temperature (HPHT) nanodiamonds (NDs) represent extremely promising materials for construction of fluorescent nanoprobes and nanosensors. However, some properties of bare NDs limit their direct use in these applications: they precipitate in biological solutions, only a limited set of bio‐orthogonal conjugation techniques is available and the accessible material is greatly polydisperse in shape. In this work, we encapsulate bright 30‐nm fluorescent nanodiamonds (FNDs) in 10–20‐nm thick translucent (i.e., not altering FND fluorescence) silica shells, yielding monodisperse near‐spherical particles of mean diameter 66 nm. High yield modification of the shells with PEG chains stabilizes the particles in ionic solutions, making them applicable in biological environments. We further modify the opposite ends of PEG chains with fluorescent dyes or vectoring peptide using click chemistry. High conversion of this bio‐orthogonal coupling yielded circa 2000 dye or peptide molecules on a single FND. We demonstrate the superior properties of these particles by in vitro interaction with human prostate cancer cells: while bare nanodiamonds strongly aggregate in the buffer and adsorb onto the cell membrane, the shell encapsulated NDs do not adsorb nonspecifically and they penetrate inside the cells.  相似文献   
9.
The refractive index increments of linear and branched polyethylene were determined for several solvents and various wavelengths (403, 436, 546, and 633 nm), mainly at 135°C. Differences were observed between values for linear and branched samples. Data obtained in this investigation are compared with the reported ones.  相似文献   
10.
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