The influence of oxygen on the differentiation of temperature-sensitive and temperature-insensitive Lactococcus lactis subsp. cremoris starter strains

The differentiation of temperature-insensitive and temperature-sensitive strains of Lactococcus lactis subsp. cremoris by using a modified sodium-β-glycerophosphate/milk medium is described (temperature-insensitive strains are defined as those that continue to grow at 38°C and temperature-sensitive strains as those that do not grow, or grow poorly, at 38°C). The physiological basis for the differentiation assay was examined by using L. lactis subsp. cremoris strains 2146 (temperature-insensitive) and 2182 (temperature-sensitive) as test strains. After aerobic incubation on the medium, strain 2146 formed uniform colonies, 0·5 mm in diameter, while strain 2182 formed larger colonies, 1·0–1·5 mm in diameter. The differential was dependent on the medium constituents, on an aerobic gas phase, and on the effects of H₂O₂ generated within the colonies. The addition of 0·5% (w/v) pyruvate to the medium facilitated the growth of colonies of strain 2146 to 3-mm diameter, while the colony size of strain 2182 remained at 1-mm diameter, and thus the colony-size differential between strains was reversed. The growth of both strains was inhibited at 0·4–0·8% air saturation during suspension culture in sodium-β-glycerophosphate/milk medium. The inclusion of catalase in the cultures overcame the growth inhibition. There was no observable difference between the two strains in their oxygen sensitivity or NADH oxidase/peroxidase enzymology.     

Teaching mental patients to use client-centered and experiential therapeutic skills with each other.

Investigated the effects of teaching 42 acute and chronic schizophrenic inpatients (mean age 27.6 yrs) to use client-centered reflective and experiential focusing skills with each other. To determine whether these skills could be learned, Ss were pre- and posttested with the Hinterkopf-Brunswick Talker and Helper Rating Scales. Results indicate that Ss were successful in learning the majority of skills taught. Administration of the Discharge Readiness Inventory revealed significant improvement in experimental Ss as compared to controls on community adjustment potential. In addition to statistical results, patients reported other beneficial effects from the training. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The restricting effects of awareness: A paradox and explanation.

Ss were shown tachistoscopically-presented word stimuli to test the distinction between the perceptual processes of registration (what could be called physiological or sensory threshold) and awareness (or the cognitive threshold). The presentation consisted of a stimulus word followed by series of words associated to the stimulus word either in terms of meaning or structural resemblance. Recall of words presented subliminally or supraliminally was facilitated with degree of awareness of actual stimulus word; with greater awareness of the word, associational recall was for words that structurally resembled S word; without awareness, recall was determined by associative meaning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spatial coherence of backscatter for the nonlinearly produced second harmonic for specific transmit apodizations

To be successful, correlation-based, phase-aberration correction requires a high correlation among backscattered signals. For harmonic imaging, the spatial coherence of backscatter for the second harmonic component is different than the spatial coherence of backscatter for the fundamental component. The purpose of this work was to determine the effect of changing the transmit apodization on the spatial coherence of backscatter for the nonlinearly generated second harmonic. Our approach was to determine the effective apodizations for the fundamental and second harmonic using both experimental measurements and simulations. Two-dimensional measurements of the transverse cross sections of the finite-amplitude ultrasonic fields generated by rectangular and circular apertures were acquired with a hydrophone. Three different one-dimensional transmit apodization functions were investigated: uniform, Riesz, and trapezoidal. An effective apodization was obtained for each transmit apodization by backpropagating the values measured from within the transmit focal zone using a linear angular spectrum approach. Predictions of the spatial coherence of backscatter were obtained using the pulse-echo Van Cittert-Zernike theorem. In all cases the effective apodization at 2f was narrower than the transmit apodization. We demonstrate that certain transmit apodizations result in a greater spatial coherence of backscatter at the second harmonic than at the fundamental.     

Condensation on a vertical rotating finned tube

Experiments have been carried out to determine the effect of centrifugal force on the rate of condensation of vapors. Methanol and isopropanol vapors were condensed on a vertical rotating finned tube and it was found that the data could be correlated by the equation: Condensation film heat transfer coefficients in excess of 5,700 W/(m² °K) and 4,200 W/(m² °K) were obtained for methanol and isopropanol respectively at a tube rotational speed of 1,000 rpm.     

Getter sputtering—a review

The historical background and current use of getter sputtering are reviewed and it is shown that the process often occured in early apparatus because of fortuitous layout of the chamber components. Getter systems are classified into “static” and “ynamic” according to the gas flow and pumping conditions. In conclusion mass spectra are given of the gas atmospheres in an r.f. getter sputtering plant when depositing tantalum. It is shown that gettering reduces the gaseous impurities. However, provision of the extra getter target requires use of increased power input. Otherwise the deposition rate can fall (from an overall reduction in ion current density) which increases in the desired coating the proportion of sorbed impurity from gas released in the substrate coating vessel.