Frequency limitation of GaAs transferred-electron devices: influence of operating d.c. and r.f. field values

The possibility of making use of the transferred-electron effect for power generation in the whole millimetre-wave range is shown for long and uniform-field GaAs samples. A great improvement in the upper frequency limit under large-signal operation is reported.     

Isolation of yeast mutants defective for localization of vacuolar vital dyes

An application of flow cytometric sorting is used for isolation of Saccharomyces cerevisiae mutants that mislocalize vacuolar vital dyes. This screen is based on the ability of a lipophilic styryl compound, N-(3-triethylammoniumpropyl)-4-(6-(4-(diethylamino)phenyl)hexatrie nyl )pyridinium dibromide (FM4-64), to label endocytic intermediates from the plasma membrane to the vacuole membrane at 15 degreesC. Cells stained at 15 degreesC for both FM4-64 and carboxydichlorofluorescein diacetate (a vacuolar luminal vital stain), had a pronounced shift in red/green fluorescence from cells stained at 30 degrees or 38 degreesC. Flow cytometric selection based on this characteristic shift allowed the isolation of 16 mutants. These comprised 12 complementation groups, which we have designated SVL for styryl dye vacuolar localization. These groups were put into three classes. Class I mutants contain very large vacuoles; class II mutants have very fragmented vacuoles; and class III mutants show the strongest svl phenotype with punctate/diffuse FM4-64 staining. Limited genetic overlap was observed with previously isolated mutants, namely svl2/vps41, svl6/vps16, and svl7/fab1. The remaining svl mutants appear to represent novel genes, two of which showed temperature-sensitive vacuole staining morphology. Another mutant, svl8, displayed defects in uptake and sorting of phosphatidylcholine and phosphatidylethanolamine. Our flow cytometric strategy may be useful for isolation of other mutants where mislocalization of fluorescent compounds can be detected.     

2-2''-Pyridylisatogen, a selective allosteric modulator of P2 receptors, is a spin trapping agent

We studied the role of parasympathetic division of vegetative nervous system in regulation of the intestine activity in rats subjected to bilateral subdiaphragmal vagotomy, the response of the neuromuscular apparatus of the small intestine to stimulation by aceclydine taken as an example. Intravenous injection of aceclydine (0.5 mg/kg) into intact animals is accompanied by characteristics changes in the electrical and contractile activities of the intestine, which reflect its enhanced motor activity. Vagotomy leads to changes of response of the intestine to pharmacological stimulation, most expressed within 3, 7, and 30 days. It was proposed that distortion of reactive properties of the intestine contractile system under these conditions is related to functional changes in rhythm-setting neurons of intramural ganglia and M-cholinoreceptors of neuromuscular synapses.     

Compensation satisfaction: Its measurement and dimensionality.

This research examined the influence of contextual variables on the factor structure of Heneman and Schwab's (1985) Pay Satisfaction Questionnaire (PSQ) and further explored the dimensionality of the compensation satisfaction construct. The PSQ is intended to measure four aspects of compensation: pay level, pay raises, pay structure-administration, and benefits. Previous research showed support for the pay level and benefit subscales, with equivocal results for the raises and structure-administration subscales. In this study, using data obtained from 1,007 employees of a manufacturing firm and 95 nursing home employees, we found that PSQ factor structure varied by employee job classification (salaried-exempt, salaried nonexempt, and hourly) and may also vary by other contextual factors such as company labor-relations compensation policy. The question of the underlying dimensionality of the compensation satisfaction construct cannot be adequately addressed by use of the current version of the PSQ. Implications for research and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Noise of hot carriers in the channel of n silicon junction gate field effect transistors

At 77 K the noise current spectral density of n type silicon channel junction gate field effect transistors is about 70 times higher than predicted by the theory. This discrepancy is explained by the authors taking into account the noise temperature of hot electrons which is measured for n Si at 77 K vs the electric field. The theory of noise in FETs is subsequently modified and gives results in reasonable agreement with the experiment. This theory can be applied to every one dimensional device.     

Deviation from stoichiometry in α-HgI2

Measurements of lattice constants, density and transition temperature have been carried out on α-HgI₂ single crystals grown both from vapor phase and from solution under different stoichiometric conditions. Stoichiometry deviations on both Hg- and I-rich sides were found. Large supersaturations extending on the Hg-rich side up to about 4 × 10^?2$\text{I}{}_{\mathrm{Hg}}\text{HgI}{}_2$ mole ratio and on the I-rich side up to about 10^?2$\text{I}{}^{\mathrm{?}}{}_3\text{HgI}{}_2$ mole ratio were accomodated by the crystals. The interpretation of the results supports the assumption of the presence of mercury interstitials in the Hg-rich crystals and of I^?₃ anions in the I-rich crystals. The large deviations from stoichiometry are attributed to the non-stoichiometry of the mother phase and to the easiness of the crystal structure for accomodating interstitials rather than to characteristic thermodynamic equilibria of interstitials in the lattice.