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21.
A pure culture of Microcystis aeruginosa or Anabaena variabilis, the representatives of water blooming algae, was exposed to low-pressure (LP) or medium-pressure (MP) UV lamps. Irradiated pure culture suspension was subsequently incubated for 7d under white light fluorescent lamps. During incubation, profiles of the number of cells, DNA damage and photosynthetic activity were determined. When UV fluence was 600mJ/cm(2), M. aeruginosa cell numbers decreased throughout the 7-d incubation period, to produce 1.5log reduction (LP) or 1.2log reduction (MP) compared with control. The amount of DNA damage was 2.02x10(-4) ESS/base (LP) and 3.42x10(-4) ESS/base (MP) just after UV irradiation, which became 0.05x10(-4) ESS/base and 0.23x10(-4) ESS/base, respectively, after 3d incubation. However, cell number kept decreasing, even after DNA repair. Photosynthetic activity decreased by 1.5log within 1d (LP) or 3d (MP). Thus, reduction in photosynthetic activity could contribute to the reduction in M. aeruginosa cell numbers. A. variabilis cell numbers reduced by 2.3log (LP) or 2.2log (MP) during the 7-d incubation period; however, after DNA damage repair, cell number began to increase. The amount of DNA damage was 6.07x10(-4) ESS/base (LP) and 4.48x10(-4) ESS/base (MP) just after UV irradiation, which became 0.23x10(-4) ESS/base and 0.40x10(-4) ESS/base, respectively, after 3d incubation. No reduction was observed in photosynthetic activity/cell. Therefore, DNA damage is the main contributor of the reduction in cell number of A. variabilis. 相似文献
22.
Weighting matrix of quadratic performance index and design method of optimal deadbeat control system
Yuichi Matsushima Shinichiro Wakamiya Hiroshi Murata 《Electrical Engineering in Japan》2000,133(1):53-63
A method of determination of the weighting matrix of the quadratic performance index and a method of design of an optimal deadbeat control system are discussed. First, the relationship between the weighting matrix of the quadratic performance index and the extra poles of the overparametrized pulse transfer function model is indicated. Next, a method of design of an optimal deadbeat control system is explained. Lastly, to demonstrate the effectiveness of the proposed method, some numerical examples are presented. © 2000 Scripta Technica, Electr Eng Jpn, 133(1): 53–63, 2000 相似文献
23.
Arami S Sato M Futo S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(3):205-210
DNA barcoding is a species identification technique, which uses a very short DNA sequence from a region of approximately 650 base-pairs in the 5'-end of the mitochondrial cytochrome c oxidase subunit I gene as a marker to identify species of mammals and fishes. The applicability of DNA barcoding for identification of fish species consumed in Japan was studied. Among thirty-one fresh or processed fishes were obtained from the market, two samples could not be identified due to lack of data in the Barcode of Life Data (BOLD) database. However, BLAST-search of 16S rRNA genes in the National Center for Biotechnology Information (NCBI) database and the PCR-RFLP method published by the Food and Agricultural Materials Inspection Center (FAMIC) were found to be applicable to identify these 2 fishes. The results show that the DNA barcoding technique is potentially useful as a tool for confirming the proper labeling of fish species in the Japanese market. 相似文献
24.
Kazunari Katayama Sanshiro Kasahara Shinichiro Ishikawa Satoshi Fukada Masabumi Nishikawa 《Fusion Engineering and Design》2011,86(9-11):1702-1705
Tungsten deposits were produced by sputtering method using hydrogen isotope RF plasma, and the density and the incorporated components in the deposits were investigated. The density changed in the range from 14.2 g/cm3 to 6.1 g/cm3, and hydrogen isotope retention changed in the range from 0.25 to 0.05 as (H + D)/W by the difference of deposition conditions. Both the density and hydrogen isotope retention tended to decrease with an increase of pressure. Even though a deuterium gas was used for producing tungsten deposits, not only deuterium but also hydrogen, oxygen and water vapor were incorporated in the deposits. It is considered that the incorporation of these components originated in water vapor unintentionally existing in the vacuum chamber. 相似文献
25.
Shinichiro Nagano 《Journal of the Society for Information Display》2012,20(9):517-525
It was determined that the discharge in the vicinity of ribs should be intensified to obtain low‐voltage, high‐luminous efficacy, and high module efficiency. One possible way is to increase the space between ribs and the discharge surface. Even if the amount of space increases by only 2 or 3 µm, it still results in low discharge voltage, large discharge current, and high luminous efficacy. For that reason it might be important to control the micron‐sized particles included in the MgO crystal dispersed layers. Another preferable way is to use ribs with a low electric permittivity (ε) that are represented by porous ribs. Moreover, low‐ε ribs diffuses the high‐energy spots in plasma, resulting in a high luminous efficacy. They feature a significantly lower sustain voltage and a smaller parasitic capacitance as well to facilitate a help high module efficiency. Also, highly porous ribs are expected to increase their practical use in aspects of mechanical strength and impurity gas exhaustion. 相似文献
26.
Evaluation of standing‐sitting support system with passive rotational seat mechanism in standing motion 下载免费PDF全文
Hiroyuki Sogo Tomohiro Henmi Shinichiro Shobako Kohei Ishii Suguru Eto Yuta Ogata 《Electrical Engineering in Japan》2018,205(2):16-25
Since a decrease in muscle mass of elderly people, the physical burden of them in standing‐sitting motion of a seat are increasing than young people. For this problem, several standing‐sitting support systems have been developed, and evaluations of these systems focusing on a reduction of physical load have been discussed. However, these evaluations are of support systems with an active actuators or of support systems when they use a handrail and a standing aid. Thus, an evaluation of a support system with only passive actuators has not been reported. In this paper, in standing motion with using a standing‐sitting support system with passive rotational seat mechanism which our group proposes, we objectively evaluate an effectiveness of the passive rotational seat mechanism by statistical analysis. 相似文献
27.
A Kimura M Suzuki M Tohma T Inoue F Endo S Kagimoto A Matsui M Kawai M Hayashi T Iizuka H Tajiri H Kato 《Canadian Metallurgical Quarterly》1998,27(5):606-609
This report examines the reliability of nighttime blood pressure dipping. Twenty-one individuals were studied twice with ambulatory blood pressure monitoring. On one occasion they were studied as outpatients, and on the other as inpatients on a clinical research ward. Blood pressure monitoring revealed the expected dip in blood pressure at nighttime. However, there was little test-retest reliability across the two settings. The test-retest correlations for the dip in blood pressure across the two settings were nonsignificant for systolic, diastolic, and mean arterial blood pressure. Caution is advised before diagnosing dipping or nondipping on the basis of one 24-h ambulatory blood pressure recording. 相似文献
28.
A Trecca T Fujii S Kato T Hasebe H Tajiri S Yoshida 《Canadian Metallurgical Quarterly》1998,30(5):493-495
Small advanced cancers (less than 10 mm in size) have rarely been described in the literature, mainly due to their difficult endoscopic diagnosis. A total of 5120 colonoscopic examinations were performed at the National Cancer Center Hospital East; three cases (0.05%) of small advanced cancer were found. The indigo carmine dye spraying technique with magnifying endoscopy was used for diagnosis. All cases were flat and depressed lesions (8, 9 and 9 mm in size respectively) with V type pit pattern at the magnifying observation. Histology showed three cancers with invasion to the proper muscle layer and two cases of lymph node metastasis. K-ras point mutation was negative in all cases, while p53 stained in two out of the three cases (one diffuse and one focal). It is concluded that small advanced colorectal adenocarcinomas are a reality. Our data on their macroscopic appearance and histology confirm their high malignant potential. 相似文献
29.
M Kage T Fujisawa K Shiraki T Tanaka T Fujisawa A Kimura K Shimamatsu E Nakashima M Kojiro M Koike Y Tazawa D Abukawa M Okaniwa H Takita A Matsui T Hayashi T Etou S Terasawa K Sugiyama H Tajiri A Yoden Y Kajiwara M Sata Y Uchimura 《Canadian Metallurgical Quarterly》1997,26(3):771-775
Limited information is available regarding the histology of hepatitis C virus infection in children. The aim of this study was to determine the histological pattern of chronic hepatitis C (CHC) in children, and liver biopsy specimens from 109 pediatric patients with CHC were examined. Each biopsy specimen was evaluated based on a numerical scoring system for the stage of fibrosis (1-4), the grade of portal/periportal necroinflammation (0-4), the grade of lobular necroinflammation (0-4), and their sum (final grade). The histological lesions considered to be characteristic of chronic hepatitis were also evaluated. None of the children had liver cirrhosis, and 105 cases (97%) were stage 1 or 2. Only 4 children were stage 3. Two of these 4 cases showed hemosiderosis. A significant correlation was observed between the staging score and the final grade in the pediatric patients (r = .59; P < .0001). The histological characteristics of adult CHC, such as lymphoid aggregate, bile duct injury, and fatty changes, were also observed in the children. In conclusion, the majority of children with CHC presented with mild fibrosis, but a few showed CHC with lobular distortion and hemosiderosis. Frequent blood transfusion may aggravate hepatic lesions in pediatric CHC. 相似文献
30.