Contribution of known endocrine disrupting substances to the estrogenic activity in Tama River water samples from Japan using instrumental analysis and in vitro reporter gene assay

To quantitatively characterize the substances contributing to estrogenic activity in river water, in vitro bioassay using MVLN cells and instrumental analysis using liquid chromatograph–mass spectrometer (LC/MS) or liquid chromatograph–tandem mass spectrometer (LC/MS/MS) were applied to river water extracts taken from various locations in the Tama River, Japan. Tama River water samples were extracted using solid phase extraction and the crude extracts were fractionated by high-performance liquid chromatography (HPLC) into 10 fractions. The sixth fraction contained nonylphenol (NP) and octylphenol (OP) at concentrations in the range of 51.6–147 and 6.9–81.9 ng/L, respectively (concentrations corresponding to the original sample volumes). No estrogenic activity, expressed as 17β-estradiol equivalents (E2-EQ_B), however, was observed in this fraction (<0.6 ng-E2eq/L). Instrumentally determined estrogenic activity (E2-EQ_C), which is the concentrations of NP and OP multiplied by their corresponding relative potency, was below the detection limit of the MVLN cell bioassay. Estrogenic activities were detected only in HPLC fraction nos. 7, 8 and 9. Estrone (E1), estradiol (E2) and bisphenol A (BPA) were detected in these fractions. Estriol (E3) and ethynylestradiol (EE2) were not detected (<0.2 ng/L) in these fractions. The calculated E2-EQ_C for BPA was below the detection limit of bioassay. The E2-EQ_C for E1 and E2 were on the same order as the estrogenic activity determined by the bioassay (E2-EQ_B). The ratios of E2-EQ_C and E2-EQ_B for E1 and E2 in the three factions collectively (nos. 7–9) were 0.49–0.97 and 0.29–1.12, respectively. Above results indicated that the major causal substances to the estrogenic activity in the Tama River were E1 and E2.     

Two different types of age-hardening behaviors in commercial dental gold alloys

Age-hardening behavior during continuous heating in commercial dental casting gold alloys was investigated by means of electrical resistivity measurements, hardness tests and X-ray diffraction. Two distinguishable behaviors were detected. It is considered that the difference was attributed to the amount of platinum, and the atomic ratio of gold and copper in each alloy. The phase transformations during continuous heating progressed into two steps (stages I and II). Increase of the platinum addition in gold-based alloys retards the rate of the reaction and decreases remarkably the amount of stage I.     

Effects of defocus and algorithm on optical step height calibration

Defocus effects on step height measurements by interferometric microscopy are estimated using different algorithms to calculate the step height. The interferometric microscope here is a Mirau-type with a 20x objective and a numerical aperture (NA) of 0.4. Although the focus is adjusted within the range of the depth of focus, a defocus corresponding to 4 fringes (1.3 μm) distorts the measured profile into a curve with a radius of curvature of about 24 m. The effect of this distortion on step height determination by a basic ISO step height algorithm is estimated to be 0.11 nm/fringe. An algorithm developed by NIST and a second-order fitted ISO step-height algorithm show good robustness against defocus errors. Because of sample imperfection, a discrepancy of about 1 % exists among step-height values determined by the different algorithms at the optimum fringe contrast position. It has been pointed out theoretically that the NA correction factor varies with the difference of optical path length between the sample and the reference surface. However, in our case, the changes of optical path length do not change the NA correction factor by more than 0.3 %.     

Continuous path control of a 5-DOF parallel-serial hybrid robot

Using the 5-degree of freedom parallel-serial hybrid robot, to realize the de-burring, new forward and inverse kinematic calculation methods based on the “off-line teaching” method are proposed. This hybrid robot consists of a parallel stage section and a serial stage section. Considering this point, each section is calculated individually. And the continuous path control algorithm of this hybrid robot is proposed. To verify the usefulness, a prototype robot is tested which is controlled based on the proposed methods. This verification includes a positioning test and a pose test. The positioning test evaluates the continuous path of the tool center point. The pose test evaluates the pose on the tool center point. As the result, it is confirmed that this hybrid robot moves correctly using the proposed methods.     

Cross-section analysis of electric devices by scanning capacitance microscope

Carrier influence of semiconductor devices is important as it affects the function of the device. In this experiment, the carrier density distribution in the cross-section of semiconductor device was analyzed by SCM: Scanning Capacitance Microscope which is one of the measuring mode of SPM: Scanning Probe Microscope.This paper describe measurement result of change in carrier density by the gate voltage at p channel area of CMOS device and its efficiency to investigating dopant profile on 16MDRAM cross-section.     

A study on horizontal stud welding by using steel stud for flat welding

ABSTRACT

In recent years, manufacturing sites have strongly requested for the steel stud with large diameter to be welded in the horizontal position, which is difficult because of gravity. In this study, the steel stud of 19 mm in diameter was welded horizontally to the mild steel plate by using ferrule for usage in flat position. As results two kinds of weld defect were observed; lack of fusion and blowhole. The former occurred in the welding condition of too small or too large heat input, and the latter did in the range of longer arc time. Therefore, the suitable welding condition could be found in the large current and shorter arc time. When the areal ratio of weld defect to the cross section of stud was lower than 10 percent, the welded joint had enough statical strength.     

The alkylation of biphenyl over three-dimensional large pore zeolites: The influence of zeolite structure and alkylating agent on the selectivity for 4,4′-dialkylbiphenyl

Catalytic properties of three-dimensional zeolites, Y (FAU), Beta (BEA), and CIT-1 (CON) zeolites were examined in the alkylation, isopropylation, sec-butylation, and tert-butylation, of biphenyl (BP), and compared to those of H-mordenite (MOR). The selectivities for 4,4′-dialkylbiphenyl (4,4′-DABP) varied with the types of zeolite and of alkylating agent. FAU, BEA, and CON gave only low selectivities for 4,4′-diisopropylbiphenyl (4,4′-DIPB) in the isopropylation, and predominant isomers were bulky and thermodynamically unstable 2,x′-DIPB (2,2′-, 2,3′-, and 2,4′-) at lower temperatures, and bulky and thermodynamically stable 3,4′- and 3,3′-DIPB at higher temperatures: this is quite different from catalytic features over MOR, which gave 4,4′-DIPB with high selectivities at moderate temperatures. These results suggest that FAU, BEA, and CON have no shape-selective nature in the isopropylation, and that the reaction is principally controlled kinetically at lower temperatures, and thermodynamically at higher temperatures. The sec-butylation gave similar results to the isopropylation. Although the selectivities for 4,4′-di-sec-butylbiphenyl (4,4′-DSBB) were higher than those in the isopropylation, predominant isomers were 2,x′-DSBB (2,2′-, 2,3′-, and 2,4′-) at lower temperatures, and 3,4′- and 3,3′-DSBB at higher temperatures. The tert-butylation gave 4,4′-di-tert-butylbiphenyl (4,4′-DTBB) in moderate to high selectivities over all zeolites at moderate temperatures: the selectivity for 4,4′-DTBB was higher than 80% over BEA and CON; however, it still remained at 50% over FAU. FAU channels with super cages are too large for selective formation of 4,4′-DTBB.

From these results, it is concluded that the selectivity for 4,4′-DABP in the alkylation over MOR, FAU, BEA, and CON is determined by the exclusion of bulky isomers at their transition states, and that the exclusion is caused by the steric restriction at the transition states of bulky isomers by the zeolite channels.     

Simulation study of the influence of different urban canyons element on the canyon thermal environment

The heat island effect is an important issue for large cities, especially those located in hot and moist climates. The phenomenon is more severe in urban canyons because surrounding high-rise buildings allow little ventilation and dissipation of heat caused by traffic. The primary goal of the present study is to investigate the thermal environment of a major street in Osaka by intensive measurement during the summer of 2006. Osaka is the second largest city in Japan and suffers from the most severe heat island effect. In addition, several fundamental renovations and a composite renovation for the improvement of thermal environment in the urban canyon are proposed, and the efficacies of these measures are verified by computational fluid dynamics (CFD) simulation. It was found that by modifying the heights of buildings along the street and the ground surface materials and increasing the quantity of vegetation, the thermal environment can be improved by a 2.0°C. reduction in standard new effective temperature (SET^*) at maximum.     

Mutational analysis of the metabolism of 2,6-naphthalenedisulfonate by Pigmentiphaga sp. NDS-2

The metabolism of 2,6-naphthalenedisulfonate (26NDS) by Pigmentiphaga sp. NDS-2 was analyzed by isolating a mutant (NDS2-002) which slowly grew on a minimal medium containing 26NDS as the sole source of carbon. Liquid chromatography/mass spectrometry (LC/MS) analysis of metabolic intermediates in this strain revealed that 5-sulfosalicylate (5SSA) is accumulated during the degradation of 26NDS. To analyze the lower metabolic pathway, a mutant strain NDS2-008, which could not grow either on 26NDS, 5SSA or gentisate, but could on succinate as the carbon source, was isolated. When the resting cells of NDS2-008 were incubated with 5SSA or gentisate, a substance deduced to be maleylpyruvate (Zhou et al., J. Bacteriol., 183, 700-708, 2001) was commonly detected upon HPLC analysis. These results suggest that Pigmentiphaga sp. NDS-2 degrades 26NDS via 5SSA, gentisate and maleylpyruvate as intermediates.