Publications by authors named "Plass R"

It is well known that the environment in which micromechanical systems operate significantly affects their performance. It is, therefore, important to characterize micromachine behavior in environments where the humidity, pressure, and chemical composition of the ambient can be precisely controlled. Achieving such a level of environmental control presents significant challenges in view of the required instrumentation.

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Low energy electron microscope measurements of the thermal motion of 50-200 nm diameter Pb islands on Cu(111) are used to establish the nature and determine the strength of interactions that give rise to self-assembly in this two-dimensional, two-phase system. The results show that self-assembled patterns arise from a temperature-independent surface stress difference of approximately 1.2 N/m between the two phases.

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We compared reading speed with two fonts, Dutch (serif) and Swiss (sans serif). Text was displayed on a computer monitor, white letters on black, with the RSVP method. Luminance of the letters was either 146.

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The ordered domain patterns that form spontaneously in a wide variety of chemical and physical systems as a result of competing interatomic interactions can be used as templates for fabricating nanostructures. Here we describe a new self-assembling domain pattern on a solid surface that involves two surface structures of lead on copper. The evolution of the system agrees with theoretical predictions, enabling us to probe the interatomic force parameters that are crucial to the process.

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The effects of 5-vinyloxazolidine-2-thione (VOT), 1-cyano-3-butene (CYB) and various isothiocyanates on parameters of hepatic phase I and phase II biotransformation were investigated in male rats after oral treatment for 3 consecutive days. The compounds with the exception of CYB caused increases in liver weight and glutathione S-transferase activity. Cytochrome P-450 level and monooxygenase activities were decreased by the isothiocyanates and CYB.

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The subacute toxicity of benzyl isothiocyanate (BITC) was investigated in male rats given oral doses of 0, 50, 100 and 200 mg/kg body weight/day for 4 weeks. Body weight gain and food consumption were decreased with increasing doses of BITC. Haematological changes of toxicological relevance were observed in the highest dose group.

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Groups of 15 male rats were fed ad libitum for 4 weeks standard diet containing 0, 2.5, 5 or 10% rapeseed protein isolate (RPI), 2.5, 5 or 10% rapeseed extraction residue (RER) or 10% casein.

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The terminal oxidase content of Bacillus firmus OF4, a facultative alkaliphile that grows well over the pH range of 7.5 to 10.5, was studied by difference spectroscopy.

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Two protonophore-resistant mutants, designated strains CC1 and CC2, of the facultative alkaliphile Bacillus firmus OF4 811M were isolated. The ability of carbonyl cyanide m-chlorophenylhydrazone (CCCP) to collapse the protonmotive force (delta mu H+) was unimpaired in both mutants. Both resistant strains possessed elevated respiratory rates when grown at pH 7.

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Groups of male and female rats received a sucrose fatty acid polyesters containing product (SPE) in their diet for 13 weeks at levels of 0, 5, 10 or 15%. Additional groups were pair-fed to the high-dose SPE-group (standard diet, 92.5%) or given food containing 7.

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The effects of a fatty acids mixture containing nearly 50% odd numbered fatty acids (PC-Säure) were studied in a subchronic toxicity test in male and female rats. The animals received PC-Säure in their diet at levels of 0, 1.25, 2.

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Groups of male and female rats received a sucroacetoglycerides containing product (SAG) for 3 months at dietary levels of 0, 2.5, 5 and 10%. Food consumption was initially increased in females at all SAG-levels.

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Glucosylthiazolidine-4-carbonic acid, an intermediate of the Maillard reaction between D-glucose and L-cysteine, was given in doses of 0, 25, 50 or 100 mg/kg b.w. by oral intubation to male and female rats for 21 days.

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The effect of maternal bladder volume on fundal height measurements was studied in 200 non-obese Black women between 16 and 42 weeks gestation. Fundal height measurements were obtained by the same examiner immediately before and immediately after each subject voided. Examiners were blinded to fundal height measurements and the amount of urine voided.

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No sex differences could been shown after absorption and distribution of azoxybenzen in the rat. The highest level occur in the thyroid gland, the adrenals and in the fat tissues. The maximum level was reached 30 min.

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The effect of cadmium on the urinary excretion of glucose, creatinine and enzymes has been studied in adult male and female rats given the substance (70, 140 and 280 mg/kg food) for 4 weeks. Renal function tests and gel electrophoresis of urinary proteins were conducted simultaneously. Sex-dependent differences were demonstrated with regard to sensitivity of several kidney parameters and their predictive character of a possible chronic nephrotoxicity.

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Groups of male and female rats received 5-vinyloxazolidine-2-thione (VOT) in their drinking water for 13 weeks at concentrations of 0, 10, 25, 50 or 100 mg/l and 0, 2.5 or 5 mg/l respectively. Compared with the controls, there were decreases in food intake and growth of females given VOT-doses of 10 mg/l and higher.

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