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1.
A fault section detection system that uses optical magnetic field sensors and instantly detects the section in which a ground fault occurred was developed for 66 kV underground multiterminal systems having Y-branch joint boxes. The optical magnetic field sensor, which is based on the Faraday effect in Bi-doped YIG ((BiYbGd)3Fe5O12) having a large Verdet constant, detects cable conductor currents of 0 to 2000 A with high precision with the use of a laminated magnetic ring core of silicon steel plates. Sensors and a fault section detector/indicator of a system are connected with optical fibers capable of nonrepeated transmission of over 6 km  相似文献   
2.
Recently, the effects of antibacterial peptides are suggested to have therapeutic potential in Alzheimer’s disease. Furthermore, systemic treatment of Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS) induced Alzheimer’s disease-like neuropathological changes in middle-aged mice. Then, we examined whether human β-defensins (hBDs), antimicrobial peptides produced by the oral mucosa and salivary glands, can suppress Pg LPS-induced oxidative and inflammatory responses by microglia. hBD3 (1 μM) significantly suppressed Pg LPS-induced production of nitric oxide and interleukin-6 (IL-6) by MG6 cells, a mouse microglial cell line. hBD3 (1 μM) also significantly inhibited Pg LPS-induced expression of IL-6 by HMC3 cells, a human microglial cell line. In contrast, neither hBD1, hBD2 nor hBD4 failed to inhibit their productions. Furthermore, hBD3 suppressed Pg LPS-induced p65 nuclear translocation through the IκBα degradation. Pg LPS-induced expression of IL-6 was significantly suppressed by E64d, a cysteine protease inhibitor, and CA-074Me, a known specific inhibitor for cathepsin B, but not by pepstatin A, an aspartic protease inhibitor. Interestingly, hBD3 significantly inhibited enzymatic activities of recombinant human cathepsins B and L, lysosomal cysteine proteases, and their intracellular activities in MG6 cells. Therefore, hBD3 suppressed oxidative and inflammatory responses of microglia through the inhibition of cathepsins B and L, which enzymatic activities are necessary for the NF-κB activation.  相似文献   
3.
This study examined the utility of the domain assessment measures used in the final 2 years at Newcastle medical school in predicting performance ratings in the first year of postgraduate training (internship). Performance ratings were obtained from the clinical supervisors of two graduating classes of the University of Newcastle medical students during their five terms of internship. Three or more ratings were obtained from 57% of interns. Univariate analysis indicated that scores for three of the five domains (professional skills; identification, prevention and management of illness; self-directed learning) were significantly positively correlated with intern performance ratings. Multivariate analysis indicated that only the domain assessing identification, prevention and management of illness was predictive of higher intern performance ratings. The results support the notion that there is some value in the domain assessment model used at Newcastle in predicting the performance of junior doctors.  相似文献   
4.
A pertinent electrochemical synthesis of 2,4,6-trichloroaniline (TCA) in anhydrous media was studied. The influence of the solvent, the chlorinating reagent, the electricity passed and the nature of the anode material, were investigated. TCA was produced in electrolytic solutions whose solvents were amides with strong nucleophilicity as N,N-dimethylformamide (DMF) and N,N-dimethylacetoamide (DMAc), and was obtained selectively by the controlled potential electrolysis of aniline in the solution containing LiCl. The definition of the experimental conditions corresponding to an optimum and selective electrolysis of TCA was described.  相似文献   
5.
After the great east Japan earthquake in 2011, Japanese energy system has been expected to prioritize safety and trustworthiness. Now, distributed power systems are considered as one solution, but utilizing exhaust heat is an important task to be solved. The purpose of this study is to build a simulation model to harness waste heat of commercial buildings. We obtained two types of data: distributed power system in 1/15 scale model of supermarket, restaurant and real world energy consumption of the two buildings. Results showed cold cabinets, whose electricity was affected by temperatures outside and inside, consumed most in supermarket. While air conditioning, affected by air enthalpy of outside and inside, consumed most in restaurant. According to our simulation with gas engine, PV (photovoltaic) panel, PCM (phase change material), thermal storage, FCU (fan coil unit) and refrigerated cabinets in scale model, we could reduce 27% of CO_2 emission and 25% of running cost by selecting optimal size.  相似文献   
6.
The isolated and perfused kidney of the spontaneously hypertensive rat (SHR) exhibits an increased vascular reactivity to serotonin when compared to normotensive Wistar-Kyoto (WKY) rats. Experiments were designed to determine the involvement of a prostanoid constricting factor in the augmented response to serotonin in the SHR kidney. Kidneys taken from male (12 months) SHR and WKY rats were studied in parallel and perfused with Tyrode's solution at constant, optimal flow rates. Vasoconstrictor response were recorded as increases in perfusion pressure. The dose-response curves to serotonin obtained in the SHR were shifted to the left compared to the WKY. Indomethacin decreased the responses to the smaller doses of serotonin in the SHR, but increased those to the higher doses of the monoamine in the WKY. The responsiveness to the monoamine was no longer significantly different in the two strains in the presence of the inhibitor of cyclooxygenase. Dazoxiben, an inhibitor of thromboxane synthetase, did not alter the responses to serotonin in either the WKY and SHR kidneys. These experiments suggest that a prostanoid, but not thromboxane A2, may play a role in the augmented response to serotonin in the kidney of aged SHR.  相似文献   
7.
A new method was used to measure the characteristics of partial discharge (PD) for an active 9.5-km long-distance 275-kV XLPE cable line with insulating joints. It was found that the detection of PD and the calibration of detection sensitivity were carried out safely and easily. The proposed method includes:
  • 1 detection of PDs and injection of calibration pulses using two pairs of metal electrodes placed on PVC jackets with anti-corrosion layers separated by a joint sleeve sectionalizing insulator;
  • 2 measurement of detection sensitivity with distance using calibration pulses injected from an adjacent insulating joint;
  • 3 detection of PDs with a high S/N ratio measured at a frequency corresponding to the lowest noise level; and
  • 4 usage of rf cores attached at cross-bonding leads and wires for sheath current limiters to reduce the crosstalk of signal and noise through these lines at insulating joints.
Using a combination of these techniques, the highest detection sensitivity was 1 pC in the vicinity of an insulating joint, and 15 pC at 617 m from the adjacent joint. The sensitivity obtained by the conventional PD measurement using a low-frequency method was at most 1000 pC.  相似文献   
8.
The feasibility of using NIR reflectance spectroscopy to estimate the FA composition of sesame seed (Sesamum indicum L.) samples from the National Institute of Crop Science of Japan and from Myanmar was examined. Multiple linear-regression analyses of NIR sepctral data and chemical data for whole seeds were carried out to develop calibration equations for predicting the proportion of each of the four major FA in sesame seeds from the total FA composition. The SE of prediction (SEP) was 0.616% for palmitic acid, 0.348% for stearic acid, 1.051% for oleic acid, and 0.826% for linoleic acid. This NIR method provides a simple, rapid, and nondestructive means of estimating the FA composition of sesame seeds for breeding selection, regardless of the color of the sesame seed coats. However, the proportions of palmitic and stearic acids could not be reliably measured because their SEP were almost as great as the SD of their concentrations in the set of prediction samples. The relationship between NIR spectral patterns and the FA composition of sesame seeds also was examined. The correlation coefficient calculated for the standardized second-derivative NIR spectral readings at 1708 nm and the percentages of linoleic acid was −0.830. A rough estimate of the proportion of linoleic acid in the total FA composition of sesame seeds could be obtained even with single sesame seeds, except for those with a black coat, based on NIR spectral pattern analysis using the wavelength assignments of linoleic acid.  相似文献   
9.
Through investigations made on crosslinked polyethylene (XLPE) insulated power cables that had experienced failures, blue-colored water trees were observed in addition to ordinary white water trees. The blue water tree was found to be much more harmful than the white water tree, since more electrical trees started at the blue trees. Elemental analysis revealed that iron and sulfur exist in the blue tree. In the case of this blue water tree, space charge exists abundantly but only at the tree tip, while no charge signal is observed on the electrode from which the tree starts. This indicates that the conductivity of the blue tree is very high. This is considered to be the main reason of the harmfulness of this tree  相似文献   
10.
Benzoic acid catalysts bearing two amide groups that increase the Brønsted acidity of the carboxylic acid moiety by internal hydrogen‐bonding interactions were designed as a novel class of carboxylic acid catalysts for the Friedel–Crafts reaction of indoles with β‐nitrostyrenes and 3,3‐disubstituted 3H‐indoles to obtain the corresponding Friedel–Crafts adducts in high yields. The internal hydrogen‐bonding benzoic acid catalysts have a relatively high Brønsted acidity compared with benzoic acid based on the pKa measurements in DMSO by UV spectrophotometric titration.

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