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排序方式: 共有519条查询结果,搜索用时 33 毫秒
1.
Masaya Takahashi Akinori Nakata Takashi Haratani Yasutaka Ogawa Heihachiro Arito 《Ergonomics》2004,47(9):1003-1013
A worksite study was conducted to examine whether a 15-min nap during a post-lunch rest period would affect subsequent alertness, performance, and nocturnal sleep in eight factory workers under a 3-week protocol. Subjects were asked to take the nap at 12:30 h on a reclining chair during the nap week, and to remain awake during the no-nap week. The order of these 2 weeks was counterbalanced between the subjects. During the third, follow-up week, each subject determined whether or not she/he would nap. Alertness on the job and nocturnal sleep were assessed using a sleep diary. Wrist activity was also recorded during sleep at night. Choice reaction time task (RT) was performed at 10:00 and 15:00 h every day of the nap week and every other day of the no-nap and follow-up weeks. Perceived alertness was significantly higher in the afternoon after nap than after no nap at the end of the week. Similar effects were observed during the follow-up week where almost half of the subjects napped. No significant differences between the three weeks were found for RT performance or nocturnal sleep. Workers' attitudes toward the nap were favourable. Although further intervention research is required, our results suggest that post-lunch napping may have the potential to promote daytime alertness at work. 相似文献
2.
H Goto K Yuasa H Sakamaki K Nakata I Komuro M Iguchi T Okamura R Ieki S Tanikawa H Akiyama Y Onozawa Y Mochida 《Canadian Metallurgical Quarterly》1996,17(5):855-860
To detect cytomegalovirus-associated interstitial pneumonia (CMV-IP) in recipients of BMT in its earliest stage, five CMV methods were assessed for their usefulness using bronchoalveolar lavage fluid as the test specimen. Of the 43 cases enrolled in the study, PCR was positive in 12 cases, shell vial in eight, culture in eight and cytology in three. There were no positive cases in in situ hybridization. Based on this result, the 43 cases were classified into four groups: Group 1, three cases: positive in PCR, shell vial and cytology; Group 2, five cases: positive in PCR and shell vial; Group 3, four cases: positive only in PCR; and Group 4, 31 cases: negative in all CMV tests. Cases in Group 1 were judged as having the highest risk of overt CMV-IP. They were successfully treated with a combination of ganciclovir and immunoglobulin. Group 2 was diagnosed as having active CMV infection and ganciclovir monotherapy was effective for these patients. Groups 3 and 4 were not given anti-CMV therapy, but they were free from CMV-related manifestations throughout the study. The sensitivity and specificity of each survey method for the detection of Groups 1 and 2 were 1.0 and 0.89 in PCR, 1.0 and 1.0 in shell vial, 0.88 and 1.0 in culture, and 0.38 and 1.0 in cytology. Similarly, the positive and negative predictive values were 0.67 and 1.0 in PCR, 1.0 and 1.0 in shell vial, 1.0 and 0.97 in culture, and 1.0 and 0.88 in cytology. Thus, CMV survey on bronchoalveolar fluid was thought to be useful in detecting post BMT CMV-IP in its earliest stage. 相似文献
3.
T Shimizu I Narabayashi Y Ogura Y Uesugi K Tabuchi R Namba Y Nakata R Matsui K Sueyoshi T Kawai 《Canadian Metallurgical Quarterly》1995,13(3):109-113
The purpose of this study was to evaluate the clinical usefulness of three-dimensional (3D) images of the bronchi obtained using helical CT. Thirteen patients with lung cancer, one with tracheal diverticulum, and one with bronchial amyloidosis were examined. The CT scanner employed was the Toshiba Xforce. The helical CT scan cycle consisted of 20 continuous rotations, each requiring 1.5 sec, for a total scanning time of 30 sec. Scans were obtained using a 5-mm X-ray beam width, a 5-mm/1.5 sec couchtop sliding speed, and a 2-mm reconstruction interval. 3D images were reconstructed using a CEMAX VIPstation. The optimal lower and upper threshold CT values for 3D images of the bronchi were -650 and -100 HU, respectively, and 3D images clearly depicted endobronchial lesions. Cartilage crescents were also demonstrated, but longitudinal and circular mucosal folds could not be visualized. In conclusion, 3D images of the bronchi acquired using helical CT were useful in evaluating endobronchial lesions. 相似文献
4.
T Hanaoka A Sawaumi K Ohtsuka K Nakata K Taguchi O Shimojima 《Canadian Metallurgical Quarterly》1996,9(3):257-264
The nature of the events whereby the reactive intermediates resulting from the bioactivation of bromobenzene and furosemide induce hepatotoxicity is unknown. To examine a role for disturbances in intracellular calcium homeostasis, secondary to a depletion in cellular reduced glutathione (GSH) and reduced protein thiols (PSHs), isolated mouse hepatocytes were exposed to cytotoxic concentrations of bromobenzene or furosemide. Cytosolic calcium concentration, as well as thiol status, was determined. The incubation of hepatocytes with 3.0 mM bromobenzene, and subsequent additions (1.2 mM) of the agent every hour, resulted in significant GSH depletion. The loss of plasma membrane integrity at 1.5 h preceded both a rise in the cytosolic Ca2+ concentration and depletion of total PSH content. Furosemide (1.0 mM) produced a 70% depletion in cellular GSH content in isolated hepatocytes. The initiation of cell damage occurred concurrently with both a rise in the cytosolic Ca2+ concentration and a depletion of total PSH content 4 h following furosemide addition. Since the increase in cytosolic Ca2+ did not precede cytotoxicity, these results do not support an initiating role for Ca2+ deregulation in bromobenzene and furosemide hepatotoxicities. In addition, depletion of PSH content did not correlate with bromobenzene- or furosemide-induced cytotoxicity. 相似文献
5.
6.
An improved T -Ω method that can analyze magnetic fields produced not only by eddy currents but also by magnetizing currents is proposed. The method is applied to the analysis of 3-D eddy-current models with holes. The usefulness of the method is investigated by comparing calculated results with measured results and with results obtained by the A -Φ method. The T -Ω method has the advantage that the CPU time can be considerably reduced when most of the analyzed region is current-free and the eddy current flows two-dimensionally. The method is especially effective when the shape of the winding is simple and the distribution of magnetizing current is known beforehand. It is not effective when most of the analyzed region is current-carrying 相似文献
7.
Yamada T. Nakata Y. Hasegawa J. Amano N. Shibayama A. Sasago M. Matsuo N. Yabu T. Matsumoto S. Okada S. Inoue M. 《Solid-State Circuits, IEEE Journal of》1991,26(11):1506-1510
A 64-Mb dynamic RAM (DRAM) has been developed with a meshed power line (MPL) and a quasi-distributed sense-amplifier driver (qDSAD) scheme. It realizes high speed, t RAS=50 ns (typical) at V cc=3.3 V, and 16-b input/output (I/O). This MPL+qDSAD scheme can reduce sensing delay caused by the metal layer resistance. Furthermore, to suppress crosstalk noise, a V SS shield peripheral layout scheme has been introduced, which also widens power line widths. This 64-Mb DRAM was fabricated with 0.4-μm CMOS technology using KrF excimer laser lithography. A newly developed memory cell structure, the tunnel-shaped stacked-capacitor cell (TSSC), was adapted to this 64-Mb DRAM 相似文献
8.
Tetsuya Murai Yoshiharu Sato Germano Resconi Michinori Nakata 《Electronic Notes in Theoretical Computer Science》2003,82(4):186
The concept of granular computing is applied to Aristotle's categorical syllogism. Such kind of reasoning is called granular reasoning in this paper. For the purpose, two operations called zooming in & out are introduced to reconstruct granules of possible worlds. 相似文献
9.
M. Biancardo K. Taira N. Kogo H. Kikuchi N. Kumagai N. Kuratani I. Inagawa S. Imoto J. Nakata 《Solar Energy》2007,81(6):711-716
Microspherical solar cells and modules have been fabricated. The spherical nature of these semi-transparent devices allows the microspherical cells to harvest both directly incident and diffuse components of sunlight thereby improving the solar energy conversion efficiency. Indoor and outdoor characterizations of these three dimensional semi-transparent cells and modules are carried out using a Lambertian reflector in order to assess the maximum efficiency of the devices. In the absence of the reflector the cell efficiency is 13.5% under standard illumination (100 mW cm−2, A.M. 1.5, 25 °C). However, this is significantly enhanced in the presence of the reflector. Microspherical modules with the reflector are directly compared to similar semi-transparent modules comprised of traditional planar devices, in outdoor tests at low light intensity (2.5–25 mW cm−2) to further demonstrate the benefits of the design particularly at low angle of incident radiation. 相似文献
10.
Motonobu Yoshikawa Hiroshi Nakajima Takeshi Inada Yasushi Harada Masahiko Amano Yuji Nakata 《Electrical Engineering in Japan》1995,115(7):29-39
A new practical method is proposed which gives a quasi-optimal solution of the dynamic load-dispatching problem formulated by a multiconstraint multiobjective optimization problem. Here, the multiple constraints are rate reserve constraints and power flow ones, and the multiple objectives are fuel cost and CO2 emission. The proposed method is an integration of the following three techniques: (1) “Group Dispatch Scheme,” which is developed by the authors, is used to satisfy a violated constraint easily. This scheme consists of three steps. The first step is to classify all generators into two groups. One is the group which should be more loaded to satisfy the violated constraint, and the other is the should-be less loaded group. The second step is to add some load to the former group, and to subtract the same load from the latter. The third step is to dispatch each group load to each groups generators, respectively; (2) the dynamic load-dispatching algorithm is used which provides, in practical time, quasi-optimal generation trajectories; (3) the conventional weighting parametric method is used to obtain a Pareto optimal solution of multiobjective problems. The effectiveness of the method is clarified by a computer simulation on the actual power system of Kansai Electric Power Company. 相似文献