Phenol and catechol biodegradation by the haloalkaliphile Halomonas campisalis: influence of pH and salinity

Removal of aromatic compounds from alkaline and/or saline industrial wastewater is an environmental concern for industry. In addition, aromatics may be accumulating in soda lakes, unique natural systems, where the fate and toxicity of these contaminants is unknown. To determine the feasibility of aromatic compound biodegradation in saline and alkaline conditions, the effect of pH and salinity on the biodegradation of phenol as a model aromatic waste compound by the haloalkaliphilic bacterium Halomonas campisalis was examined. Phenol was degraded as a source of carbon and energy at pH 8-11 and 0-150 g/L NaCl. Metabolic intermediates catechol, cis,cis-muconate, and (+)-muconolactone were identified, thus indicating that phenol was degraded via the beta-ketoadipate metabolic pathway. Although phenol and catechol were completely degraded in all cases, small amounts of cis,cis-muconate accumulated proportionally to increases in pH. There was no noticeable influence of salinity on cis,cis-muconate accumulation except at 0 g/L NaCl where it was completely degraded. These results indicate that it may be feasible to use haloalkaliphiles forthe treatment of aromatics present in saline and/or alkaline systems. This is the first report of phenol and catechol biodegradation under combined saline and alkaline conditions.     

Acidified sodium caseinate emulsion foams containing liquid fat: A comparison with whipped cream

Aeration properties of acidified casein-stabilized emulsions containing liquid oil droplets have been compared to the whipping of dairy cream. The foam systems were characterized in terms of overrun, microstructure, drainage stability, and rheology. With acidification using glucono-δ-lactone, the casein-stabilized emulsions could be aerated to give foams of far higher overrun (>600%) than whipped cream (∼120%). The development of foam volume, stability and rheology in the aerated casein-stabilized emulsion systems was found to be strongly dependent on the pH and the concentration of added calcium ions. Whereas whipped cream is stabilized by partially coalesced fat globules, the casein emulsion foams are stabilized by aggregation (gelation) of the protein coat surrounding the oil droplets. Casein emulsion foams formed at low pH were found to be more stable than whipped cream, whilst those formed at high pH were predominantly liquid-like and unstable. Instability arose in the acidified casein emulsion foams mainly through gel syneresis. We conclude that there are substantial textural differences between whipped cream and acidified casein emulsion foams, especially in terms of the small-deformation rheology and the extent of the linear viscoelastic regime.     

1.55-μm wavelength periodic traveling-wave photodetectorfabricated using unitraveling-carrier photodiode structures

We report the first periodic traveling-wave photodetector fabricated by using unitraveling-carrier photodiodes (UTC-PDs). The photodetector comprises three UTC-PDs with a 0.06-μm absorption layer that is periodically arranged along a coplanar waveguide transmission line. The photoresponse of the photodetector is three times larger than that of a single UTC-PD. A photodetector with terminal resistors at the input end achieves a 3-dB bandwidth of 115 GHz at 1.55 μm. This is almost the same value as that for a single UTC-PD. For one without terminal resistors, the 3-dB bandwidth degrades to 56 GHz as a result of the backward-propagating microwave being reflected at the input end. These results suggest that the photodetector is well designed with both velocity and impedance matchings     

Differential Time Signaling Data-Link Architecture

A new time-based high-speed data-link architecture, which we call Differential time Signaling (DTS) is presented. A clock pulse is embedded in the transmitted signal and is used as a time reference against which the rising and falling data pulse edge timings are compared. Using the DTS approach, data encoding is achieved by spacing the time between the embedded clock edges and the data pulse edges using a hierarchical time-delay resolution assignment to each bit in the data sequence. The proposed link is shown to concentrate the signal energy in a low bandwidth while reducing clock jitter effect. A simulated 3 Gb/s 90 nm CMOS DTS link using a 500 MHz clock signal is also described to provide a flavor for a monolithic realization. As a proof of concept, 700 Mb/s and 1.6 Gb/s DTS-based links have been designed using a commercial FPGA board. The measured eye diagrams for the transmitted and received signals over a 40-inch FR4 channel are presented.     

MnGeP2 Thin Films Grown by Molecular Beam Epitaxy

Growth conditions for MnGeP₂ thin films have been investigated by using molecular beam epitaxy (MBE) method. Mn and Ge were evaporated by K-cells, and P₂ was supplied by decomposing tertialybutylphosphine (TBP). GaAs (001) and InP (001) single crystals were used as substrates. An X-ray diffraction peak, which can be assigned to (008) peak of MnGeP₂, was observed at nearly the same position as the (004) peak of GaAs. The lattice constant of the MnGeP₂ thin film was determined to be 1.13 nm assuming its crystal structure is a c-axis oriented chalcopyrite type structure. Secondary phases such as GeP, MnGe_x and MnP were observed for beam fluxes of Mn and Ge as high as 1×10^–8 Torr.     

Social support and the effectiveness of group therapy.

Collected self-report data from 37 pretest clients and 26 of the same clients at posttest who participated in 6 counseling center therapy groups. Questionnaires assessed 6 functionally different types of social support provided from 2 sources, therapy group members vs persons outside the group, together with pre- and posttest levels of 3 distress symptoms, which were depression, self-esteem, and psychological symptoms of stress. Significant improvement in symptoms was noted during the 8-wk interventions, and this improvement was related to the availability of social support, depending on the type and source of support. In general, support from sources outside the therapy group appeared to have the most impact. Levels of certain types of support differed in groups depending on whether or not the group was composed of members with a common presenting concern. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Application of AlGaAs/GaAs HBTs for wideband direct-coupled amplifiers

An AlGaAs/GaAs HBT direct-coupled amplifier has been designed and its characteristics described for the first time. The amplifier consists of two HBTs and three resistors without level-shift diodes. A superior amplifier performance of 11 dB gain with a 4 GHz bandwidth was obtained.     

Influence of electron velocity overshoot on collector transit timesof HBTs

Collector transit times of heterojunction bipolar transistors with a pronounced electron velocity overshoot effect are investigated using a simple analytical model. The effective carrier velocity, ν_eff , which is a measure for determining the transit time, is defined as π_C=W_C/2ν_eff. It is found that ν_eff is much different from the average velocity, ν_av, that is given by the traveling time through the whole collector depletion layer and the depletion width. With a higher overshoot peak velocity, the collector transit time is shorter than that estimated simply from the average velocity ν_av     

Culturally sensitive assertiveness training for ethnic minority clients.

This article serves as a comprehensive resource to help bridge the gap of cultural understanding for those using assertiveness training with ethnic minority clients. Therapists providing cross-cultural assertiveness training must be certain that gaining such skills is a value shared by the client and not imposed by the therapist. A more culturally appropriate approach includes the following general assessment strategies: determining the etiology of the lack of assertiveness; using self-report inventories that avoid words, slang, or situations that may not be meaningful to the client; and the developing norms for the cultural group for which the inventory will be used. General treatment strategies may include "message matching," backup assertion, and discriminative cue learning. Specific strategies that are relevant for each cultural group are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Species specificity of musty odor producing Phormidium tenue in Lake Kamafusa.

16S ribosomal DNA sequences of various strains of Phormidium tenue (P. tenue) in Lake Kamafusa were determined. Such P. tenue could not be distinguished under microscopic examination. From the results of the analyses of base sequences, and using a phylogenetic tree, several P. tenue with different species specificity on the sequence were found in the lake. P. tenue were divided into three groups. The first produced 2-methylisoborneol (MIB) and was close to a species from the moat of Nagoya castle. The second produced MIB and was characteristic of Lake Kamafusa. The third had a brown color like a Lake Biwa strain and was MIB non-producing. From the phylogenetic tree, it was revealed that species had not changed recently by mutation. Moreover, a detection method for P. tenue by PCR and dot hybridization was established.