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71.
72.
Fusaomi Nagata Takanori Mizobuchi Keigo Watanabe 《The International Journal of Advanced Manufacturing Technology》2011,57(9-12):1029-1041
In this paper, a desktop-size NC machine tool is first presented to have multi-application function, such as 3D-machining modes with and without handling a machining force, and profiling-control modes with and without using stick-slip motion. The NC machine tool consists of three single-axis devices with a high resolution of 1???m in position. A ball end mill called router bit or a thin wood-stick tool can be attached to the tip of the z-axis. The proposed machine tool realizes compliant motion required for the profiling control along a desired trajectory. The profiling-control mode can be applied to the lapping process of a metallic LED lens cavity. Next, a control strategy with fine stick-slip motion is further added to the profiling-control system to improve the lapping performance. The fine stick-slip motion is generated orthogonally to the direction of the tool movement. Generally, the stick-slip motion is an undesirable phenomenon to be eliminated in precision machineries. However, the proposed machine tool employs the fine stick-slip motion to partly regulate slight finishing energy. The effectiveness of the machine tool is demonstrated through an actual machining test of a wood material and a lapping test of a metallic LED lens cavity. 相似文献
73.
Ramaswamy BR Kim JW Isobe T Chang KH Amano A Miller TW Siringan FP Tanabe S 《Journal of hazardous materials》2011,192(3):1739-1745
Ultra high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) determination of four paraben preservatives (methyl, ethyl, propyl and butyl) and two antimicrobial agents (triclosan and triclocarban) belonging to personal care products (PCPs) in 20 species of fish from Manila Bay (Philippines) was performed. Detection of PCPs with greater frequency indicates the ubiquitous contamination of Manila Bay. Concentrations of total paraben were one order of magnitude higher than the antimicrobials in almost all fish, except in Stolephorus indicus and Leiognathus equulus. A positive correlation was observed between parabens concentration and fish length (r = 0.31-0.49; p<0.05 to <0.001) and fish weight (r = 0.28-0.49; p<0.05 to <0.001), but not for the antimicrobials. The estimated dietary exposure values of the four parabens in the Philippines through fish is four orders of magnitude lower than the acceptable daily intake (ADI) of 10mg/kg/day, but the values of antimicrobials are just half of the ADI of TCS. To our knowledge, this is the first report of PCPs contamination in fish from Philippines. 相似文献
74.
Takanori Sugawara Massimo Sarotto Alexey Stankovskiy Gert Van den Eynde 《Annals of Nuclear Energy》2011
The XT-ADS, an accelerator-driven system for an experimental demonstration, has been investigated in the framework of IP EUROTRANS FP6 project. In this study, the sensitivity and uncertainty analyses were performed to comprehend the reliability of the XT-ADS neutronic design. 相似文献
75.
We describe a technique, simpler than earlier ones, for using SPICE in the computation of the 1/f, step, and delta noise indices of linear and time-valiant filters. The method is based on obtaining a weighting function from the results of simulation and is demonstrated for triangular and trapezoidal shapers. The results are compared with those obtained by direct calculation. The greatest discrepancies occur when the method is applied to gated integrators, but the errors are probably due to artifacts not related to the basic method described here 相似文献
76.
Duling Xu Hongyan Li Takanori Katsube Guomin Huang Jiadi Liu Bing Wang Hong Zhang 《International journal of molecular sciences》2022,23(9)
Concurrent exposure to ionizing radiation (IR) and psychological stress (PS) may affect the development of adverse health consequences in scenarios such as space missions, radiotherapy and nuclear accidents. IR can induce DNA damage and cell apoptosis in the kidneys, thus potentially leading to renal fibrosis, which is the ultimate outcome of various chronic progressive nephropathies and the morphological manifestation of a continuous coordinated response after renal injury. However, little is known regarding the effects of concurrent IR exposure and PS on renal damage, particularly renal fibrosis. In this study, using a chronic restraint-induced PS (CRIPS) model, we exposed Trp53-heterozygous mice to total body irradiation with 0.1 or 2 Gy 56Fe ions on the eighth day of 28 consecutive days of a restraint regimen. At the end of the restraint period, the kidneys were collected. The histopathological changes and the degree of kidney fibrosis were assessed with H&E and Masson staining, respectively. Fibronectin (FN) and alpha smooth muscle actin (α-SMA), biomarkers of fibrosis, were detected by immunohistochemistry. Analysis of 8-hydroxy-2 deoxyguanosine (8-OHdG), a biomarker of oxidative DNA damage, was performed with immunofluorescence, and terminal deoxynucleotidyl transferase-mediated nick end labeling assays were used to detect apoptotic cells. Histopathological observations did not indicate significant structural damage induced by IR or CRIPS + IR. Western blotting revealed that the expression of α-SMA was much higher in the CRIPS + IR groups than the CRIPS groups. However, no differences in the average optical density per area were observed for FN, α-SMA and 8-OHdG between the IR and CRIPS + IR groups. No difference in the induction of apoptosis was observed between the IR and CRIPS + IR groups. These results suggested that exposure to IR (0.1 and 2 Gy 56Fe ions), 28 consecutive days of CRIPS or both did not cause renal fibrosis. Thus, CRIPS did not alter the IR-induced effects on renal damage in Trp53-heterozygous mice in our experimental setup. 相似文献
77.
Chemical Removal of CeO2 Segregated on the Surface of CeO2–ZrO2 Binary Oxides for Improvement of OSC
Noriyoshi Kakuta Youko Sugino Hironobu Rachi Hironobu Ohkita Takanori Mizushima 《Topics in Catalysis》2009,52(13-20):1888-1892
A chemical treatment to remove residual CeO2 phase on CeO2–ZrO2 (CZ) solid solution was carried out. A CZ was treated by H2O2 for the reduction of Ce4+ to Ce3+ and then HNO3 for the dissolution of Ce3+ compounds (H–CZ). H2-TPR, TEM-EDX and XPS analyses revealed the removal of CeO2 phase and the homogeneous distribution of Ce species. About 20% improvement in oxygen storage capacity (OSC) of H–CZ was confirmed at 773 K by the weight measurements under H2/N2 and air atmospheres, indicating that the HNO3/H2O2 treatment was effective to avoid the deterioration of the OSC by segregated CeO2 on the CZ binary oxides. 相似文献
78.
Recently, we have reported that anthocyanins show strong antioxidative activity, but no attention has been paid to anthocyanins
from the viewpoint of the reaction mechanism of alkylperoxyl radicals; therefore, we investigated the reaction products of
antioxidative anthocyanins (cyanidin 3-O-β-d-glucoside). Cyanidin 3-O-β-d-glucoside was reacted with 2,2′-azobis(2,4-dimet hylvaleronitrile) to generate the alkylperoxyl radicals, and the reaction
products were isolated by high-performance liquid chromatography. The products were identified as 4,6-dihydroxy-2-O-β-d-glucosyl-3-oxo-2,3-dihydrobenzofuran and protocatechuic acid. Based on reaction products, the antioxidative mechanism of
cyanidin 3-O-β-d-glucoside may be different from that of α-tocopherol; cyanidin 3-O-β-d-glucoside would produce another radical scavenger, as it would break down the structure and scavenge the radicals. 相似文献
79.
Protein phosphorylation/dephosphorylation on tyrosine residues are regulated by tyrosine kinases/phosphatases. The tyrosine phosphatase SH-PTP2 (PTP1D, PTP2C) interacts physically through its SH2 domain with phosphorylated epidermal growth factor receptor (EGFR). In KB cells, an oral epidermoid carcinoma, high epidermal growth factor (EGF) concentrations (10-9, 10-8 and 10-7 M) downregulate its receptor for the duration of the incubation with EGF. Thus, it was hypothesized that in KB cells, SH-PTP2 expression would also be downregulated by high EGF concentrations. This hypothesis was investigated by incubating the KB cells with increasing concentrations of EGF (0, 10-11, 10-10, 10-9, 10-8, 10-7 M) and by evaluating the expression of SH-PTP2 protein under these conditions. This study showed that EGF 10-7 and 10-8 M significantly decreased SH-PTP2 protein expression compared to controls. EGF 10-10 and 10-11 M did not change the expression of SH-PTP2 protein. We conclude that high EGF concentrations downregulate the expression of SH-PTP2 protein. 相似文献
80.
H Miyazaki K Kamishima H Miyamoto S Saito H Isobe Y Kawakami Y Narita T Okubo Y Fujioka 《Canadian Metallurgical Quarterly》1997,35(3):341-345
STUDY OBJECTIVE: To evaluate the long-term efficacy of laparoscopic Burch urethropexy. DESIGN: Pilot study. SETTING: Private practice. PATIENTS: Thirty-five consecutive women (average age 45.5 yrs, average parity 2.3, average weight 67.7 kg) treated for genuine stress incontinence between May 1992 and July 1994. INTERVENTIONS: Urethropexy was performed with curved needle suturing in 7 women, straight needle suturing in 5, and Stamey needle suturing in 23. Twenty-five (71.4%) patients had concomitant pelvic surgery. MEASUREMENTS AND MAIN RESULTS: Wilcoxon two-sample, chi2, and Fisher's exact tests were performed to determine which variables were significantly associated with surgical success. Average operating time was 190 minutes, hospitalization 24 hours, and catheterization 5 days. The cure rate of stress incontinence was 89% 3 months and 86% 1 year after surgery. At average follow-up of 34 months, only 68.6% of patients reported complete or almost complete cure, 11.4% were improved, and 20% were complete failures. The only operative variable approaching statistical significance for predicting surgical success was type of suture needle (p = 0.07), with the Stamey needle group having the highest cure rate. Women who were cured or almost cured had a significantly shorter follow-up than those who were improved or failures (p = 0.001). CONCLUSION: The success rate of laparoscopic Burch urethropexy compares with that of open Burch procedure at 1 year, but drops considerably thereafter. 相似文献