Isolation and characterization of thermophilic benzothiophene-degrading Mycobacterium sp.

A bacterial strain, SWU-4, capable of using benzothiophene (BT) as a sole carbon and energy source was isolated from a petroleum-contaminated site in Thailand and identified by 16S rRNA gene sequence analysis to be in the genus of Mycobacterium. The strain was Gram-positive, nonspore former, and grew at 50° C. Colonies of the strain on nutrient agar were rod-shaped, smooth with a convex surface, slightly mucoid, and yellow pigmented. The thermophilic Mycobacterium sp. strain SWU-4 rapidly degraded 2% (w/v) BT at 50°C. Interestingly, this strain was able to degrade a wide variety of organosulfur compounds including thiophene, bromo(α)thiophene, and 3-methylthiophene in liquid minimum medium at 50°C, which will be beneficial for industrial applications.     

Size Effect of the Immediate Surround for the Border between the Natural and Unnatural Object Color Appearance

The border luminance of the test stimulus between the natural and unnatural object color, y_ynB_u was obtained for different spatial sizes of the immediate surround to prove that _nB_u can be determined based on a new recognized visual space of illumination (RVSI) that is assumed to be constructed for the immediate surround separately from the RVSI for the subjects room itself. The _nB_u of five test stimuli were determined for six different sizes covering from zero to 1866 cm² with four different lightnesses, N4, N6 and N8, while keeping the room illuminance constant at 100 or 600 lx. The results showed that luminance of the border _nB_u gradually decreased as the size of the immediate surround was increased and that the decrease was larger for immediate surround with lower lightness. The results were interpreted as showing a new RVSI constructed for the spatial extent of the immediate surround of the test stimulus, and the RVSI was more completely constructed for larger spatial size of the immediate surround. © 2005 The Optical Society of Japan     

Dietary exposure of Thais to pesticides during 1989-1996

To monitor the exposure of the Thai to pesticide residues in foods, the intake of pesticides based on the total diet approach has been studied in Thailand continually since 1989. Food items were chosen and their proportions of daily consumption were calculated from the national food consumption survey conducted by the Department of Health in 1986. Seventy-seven items of food including drinking water were classified into 12 groups according to their sources of contamination and the analytical methods used. Shopping lists and standard procedures for collecting samples and cooking were developed. Twelve food composites from each of the 4 regions were analyzed for nearly 100 pesticides. All analyses used multiresidue analytical methods, and the total daily dietary intakes of pesticide residues were estimated from the average amount of food consumed by Thais. Among 24 pesticides found in the 8 year study, DDT, dimethoate, methamidophos, and parathion methyl were found every year. However, dietary intakes of all pesticides were far below the established acceptable daily intake. In 1999, the study methodology was redesigned to accommodate the new national food consumption survey data.     

Room Illuminance rather than Immediate Surrounding Luminance Determines Natural to Unnatural Color of an Object Border

The color of an object placed in a room goes through various modes of color appearance if its luminance is increased independently from the room illumination; from the natural object color to an unnatural object color, and to the light source color having two borders. We were interested in investigating the determining factor for the first border as it is useful in lighting design. It has been thought without a specific theory that it is the surrounding luminance that determines the border. According to a new concept of the recognized visual space of illumination (RVSI), the border is solely determined by the room illumination, and not by the luminance of the immediate surroundings of the object. In the first experiment of the present paper the border of a test stimulus was determined for various room illuminance while keeping the luminance of the immediate surroundings constant. It was shown that the border luminance was roughly proportional to the room illuminance, confirming the prediction based on the RVSI theory. In the second experiment the border was determined for varying luminance of the immediate surroundings while maintaining constant room illuminance. The border did not change, again confirming the prediction based on this theory.     

A multiplexed three-dimensional paper-based electrochemical impedance device for simultaneous label-free affinity sensing of total and glycated haemoglobin: The potential of using a specific single-frequency value for analysis

A novel three-dimensional paper-based electrochemical impedance device (3D-PEID) is first introduced for measuring multiple diabetes markers. Herein, a simple 3D-PEID composed of a dual screen-printed electrode on wax-patterned paper coupled with a multilayer of magnetic paper was fabricated for label-free electrochemical detection. The results clearly demonstrated in a step-wise manner that the haptoglobin (Hp)-modified and 3-aminophenylboronic acid (APBA)-modified eggshell membranes (ESMs) were highly responsive to a clinically relevant range of total (0.5–20 g dL⁻¹; r² = 0.989) and glycated haemoglobin (HbA1c) (2.3%–14%; r² = 0.997) levels with detection limits (S/N = 3) of 0.08 g dL⁻¹ and 0.21%, respectively. The optimal binding frequencies of total haemoglobin and HbA1c to their specific recognition elements were 5.18 Hz and 9.99 Hz, respectively. The within-run coefficients of variation (CV) were 1.84%, 2.18%, 1.72%, and 2.01%, whereas the run-to-run CVs were 2.11%, 2.41%, 2.08%, and 2.21%, when assaying two levels of haemoglobin and HbA1c, respectively. The CVs for the haemoglobin and HbA1c levels measured on ten independently fabricated paper-based sheets were 1.96% and 2.10%, respectively. These results demonstrated that our proposed system achieved excellent precision for the simultaneous detection of total haemoglobin and HbA1c, with an acceptable reproducibility of fabrication. The long-term stability of the Hp-modified eggshell membrane (ESM) was 98.84% over a shelf-life of 4 weeks, enabling the possibility of storage or long-distance transport to remote regions, particularly in resource-limited settings; however, for the APBA-modified ESM, the stability was 92.35% over a one-week period. Compared with the commercial automated method, the results demonstrated excellent agreement between the techniques (p-value < 0.05), thus permitting the potential application of 3D-PEID for the monitoring of the glycaemic status in diabetic patients.