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131.
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
132.
A plasmonic biosensor chip of silver-coated PMMA grating with a zinc oxide (ZnO) overlayer is fabricated for surface plasmon field-enhanced fluorescence (SPF) detection of Cy5-labeled green fluorescent protein (GFP). A bispecific antibody (anti-GFP x anti-ZnO antibody) prepared in our lab is densely immobilized on the sensor chip for GFP detection. The sensitivity of the plasmonic biosensors is improved due to densely packed antibodies and ZnO-coating that suppresses nonspecific protein adsorption and fluorescent quenching. With the ZnO-coated plasmonic chip, Cy5-labeled GFP of 10 pM can be detected through SPF. This sensitivity is 100 higher compared with the normal fluorescent detection on a ZnO-coated glass slide. 相似文献
133.
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
134.
Ayami Saga Masahiro Koseki Kotaro Kanno Jiuyang Chang Tomoaki Higo Daisuke Okuzaki Takeshi Okada Hiroyasu Inui Masumi Asaji Katsunao Tanaka Takashi Omatsu Sae Nishihara Yinghong Zhu Kaori Ito Hiroaki Hattori Ikuyo Ichi Yoshihiro Kamada Masafumi Ono Toshiji Saibara Tohru Ohama Shungo Hikoso Makoto Nishida Shizuya Yamashita Yasushi Sakata 《International journal of molecular sciences》2022,23(24)
Patients with psoriasis are at a higher risk of developing nonalcoholic fatty liver disease. We previously identified an oxidized derivative of cholesterol, 7-ketocholesterol (7KC), in diet-induced steatohepatitic mice. Here, we investigated whether 7KC exacerbates psoriasis-like dermatitis by accelerating steatohepatitis in mice. A high-fat/high-cholesterol/high-sucrose/bile salt diet (nonalcoholic steatohepatitis (NASH) diet) with or without 0.0125% 7KC was fed to C57BL/6 mice (7KC or control group) for three weeks to induce steatohepatitis. A 5% imiquimod cream was then applied to the ears and dorsal skin for four days to induce psoriasis-like dermatitis. Hepatic lipid accumulation and inflammatory cell infiltration were exacerbated in the 7KC group compared with the control group after three weeks. Serum tumor necrosis factor-α (TNF-α) levels were also elevated in the 7KC group (108.5 ± 9.8 vs. 83.1 ± 13.1 pg/mL, p < 0.005). Imiquimod cream increased the psoriasis area severity index (PASI) score in mice in the 7KC group (9.14 ± 0.75 vs. 5.17 ± 1.17, p < 0.0001). Additionally, Tnfa, Il23a, Il17a, and Il22 mRNA levels in the dorsal lesion were significantly upregulated. Finally, Th17 cell differentiation and the TNF signaling pathway were enhanced in the dorsal lesions and liver of mice in the 7KC group. These data suggest that steatohepatitis and psoriasis are linked by a potent, diet-related factor. 相似文献
135.
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
136.
Satoshi Kubota Kazumi Kawata Takako Hattori Takashi Nishida 《International journal of molecular sciences》2022,23(11)
Cellular communication network factor (CCN) 2 and 3 are the members of the CCN family that conduct the harmonized development of a variety of tissues and organs under interaction with multiple biomolecules in the microenvironment. Despite their striking structural similarities, these two members show contrastive molecular functions as well as temporospatial emergence in living tissues. Typically, CCN2 promotes cell growth, whereas CCN3 restrains it. Where CCN2 is produced, CCN3 disappears. Nevertheless, these two proteins collaborate together to execute their mission in a yin–yang fashion. The apparent functional counteractions of CCN2 and CCN3 can be ascribed to their direct molecular interaction and interference over the cofactors that are shared by the two. Recent studies have revealed the mutual negative regulation systems between CCN2 and CCN3. Moreover, the simultaneous and bidirectional regulatory system of CCN2 and CCN3 is also being clarified. It is of particular note that these regulations were found to be closely associated with glycolysis, a fundamental procedure of energy metabolism. Here, the molecular interplay and metabolic gene regulation that enable the yin–yang collaboration of CCN2 and CCN3 typically found in cartilage development/regeneration and fibrosis are described. 相似文献
137.
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
138.
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
139.
Yoshifumi Morita Norihiro Toya Ryosuke Takeichi Hitomi Hattori Hirofumi Tanabe Yoshiaki Takagi 《Advanced Robotics》2016,30(21):1406-1414
We developed a new training system, called ‘UR-System 2’, for the recovery of motor function of a plegic upper limb after stroke. UR-System 2, which was redesigned based on knowledge gained from clinical tests using UR-System 1, was newly equipped with a function for testing the motor function of patients, such as isolated movement. In order to verify the effectiveness of UR-System 2, we conducted the following procedures: we verified the safety of training in healthy persons; we gathered standard data on pronation and supination of healthy forearms during tests; and, we verified that the test function was effective in evaluating the recovery effect of isolated movement in two hemiplegic patients. 相似文献
140.
The fluorescent probe furaptra shows increases and decreases in the concentration of free magnesium ion, [Mg2+], in the mitochondrial matrix with changes in total Mg2+ and ligand availability. The factors involved in the calibration of these fluorescence changes in terms of absolute [Mg2+] have been investigated. The affinity of furaptra for Mg2+ is highly dependent on both temperature and ionic strength. The Kd for Mg-furaptra in solution in 100 mM KCl was found to be 2.1 +/- 0.1 mM at 25 degrees C. The use of this Kd to calculate matrix [Mg2+] is more reliable than in situ Kd measurements because ionophores, such as BrA23187 and ionomycin, do not equilibrate external Mg2+ with the matrix in an acceptable way. Furaptra is present at high concentrations (up to 500 microM) in the matrix when introduced by hydrolysis of the acetoxymethyl ester. However, absorbance spectra of aqueous solutions show no evidence of dimerization of the probe or other changes in properties at these concentrations. Fluorescence intensity at 340 nmex is strongly attenuated for matrix-sequestered furaptra, mag-fura-5, and mag-indo-1. This appears to result in part from preferential binding of the Mg-probe to mitochondrial proteins. The fluorescence of uncomplexed furaptra at 375-380 nmex seems unaffected by protein binding, however, and changes in intensity in this region of the spectrum can be used in conjunction with the Kd found in aqueous solution to estimate matrix [Mg2+]. The presence of secondary equilibria, such as protein binding, and possible changes in ionic strength may undermine exact quantitation by this method. However, values for matrix [Mg2+] obtained in this way (0.5 to 0.7 mM) correspond well to estimates by other available methods and each of these methods suffers from comparable uncertainties. 相似文献