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排序方式: 共有547条查询结果,搜索用时 15 毫秒
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Kazuo Tsubota Stephen C. Pflugfelder Zuguo Liu Christophe Baudouin Hyo Myung Kim Elisabeth M. Messmer Friedrich Kruse Lingyi Liang Jimena Tatiana Carreno-Galeano Maurizio Rolando Norihiko Yokoi Shigeru Kinoshita Reza Dana 《International journal of molecular sciences》2020,21(23)
Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint. 相似文献
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Tetsuji Kaneko Norihiko Tanaka Shinichi Ishioka Fujii Kazumi Yuichi Fukaya Katsuhiko Kumagai 《Journal of Nuclear Science and Technology》2019,56(9-10):873-880
ABSTRACTFukushima Daiichi nuclear power plants (1F) were damaged by unprecedented severe accident in the great east Japan earthquake, and seawater and freshwater had been injected as an emergency countermeasure for the core cooling. Although, the primary containment vessel (PCV) was not supposed to be exposed to diluted seawater, the PCV will be exposed to diluted seawater environment until fuel debris removal is completed. Therefore, it is necessary to establish a countermeasure of corrosion for the PCVs made of carbon steel. In this study, the effect of the addition of corrosion inhibitor, which is one of the corrosion countermeasures, was investigated by two types of corrosion tests. As a result of the immersion corrosion test, it was found that any of the three kinds of corrosion inhibitor could suppress corrosion of carbon steel. In addition, as a result of the inhibitor interim addition test, it was found that corrosion of carbon steel covered with corrosion products could be suppressed by optimizing the additive amount of corrosion inhibitor in the cooling water. 相似文献
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Shahira Said Aly Tsuyoshi Imai Mohamed Salah Hassouna Diem-Mai Kim Nguyen Takaya Higuchi Ariyo Kanno Koichi Yamamoto Rinji Akada Masahiko Sekine 《International Journal of Hydrogen Energy》2018,43(10):5300-5313
The ability of Clostridium butyricum RAK25832 to use casamino acids as a nitrogen source was investigated. Strain RAK25832 showed the capacity to utilize different types of carbon sources. With glucose as a carbon source (10 g/L), the preferred final concentration of casamino acids was 26.67 g/L, with a cumulative hydrogen production, production rate, and yield of 2505 mL H2/L, 160 mL/h, and 1.81 mol H2/mol glucose, respectively. Eighteen metal elements were screened to identify the most important metals for biohydrogen production, and four elements were optimized. The optimal medium composition was MgCl2·6H2O (0.1 g/L), K2HPO4·3H2O (6.67 g/L), NaHCO3 (2.6 g/L), and FeCl2·4H2O (0.002 g/L). Vitamin supplementation of the medium showed no significant effect on hydrogen production. Under the optimized conditions, cumulative hydrogen production reached 3074 mL H2/L. This is the first study to demonstrate the use of casamino acids as a nitrogen source by C. butyricum. 相似文献
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Tetsuji Kaneko Norihiko Tanaka Tetsushi Yamaoka Hiroshi Masaki Yuuki Masuda Masaru Iwanami 《Journal of Nuclear Science and Technology》2013,50(6):773-783
Fukushima Daiichi nuclear power plants (1F) were damaged by unprecedented severe accident in the Great East Japan Earthquake on 11 March 2011, and seawater has been injected as an emergency countermeasure for the core cooling. Although, the RPV and PCV were not supposed to be exposed to diluted seawater, they have been exposed to diluted seawater environment or high-moisture environment. Therefore, seawater corrosion has become an important issue. Immersion corrosion tests were performed for low-alloy steel of RPV material and carbon steel of PCV material in 1F cooling-water-simulated environment. As a result, the mass loss by corrosion was reduced with the decreasing temperature and chloride ion concentration. Moreover, the effects of nitrogen deaeration and Na2WO4 addition on corrosion protection were remarkable among the selected corrosion countermeasures. In addition, the integrity assessments of RPV and PCV were performed considering the reduction of plate thickness based on corrosion test data and the load condition based on earthquake response analysis results. It had been confirmed that primary stresses for RPV and PCV equipment satisfied with the allowable values until at least 15 years after the accident. 相似文献
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As the density and operating speed of complementary metal oxide semiconductor (CMOS) circuits increases, dynamic power dissipation has become a critical concern in the design and development—of personal information systems and large computers. The reduction of supply voltage, node capacitance, and switching activity are common approaches used in conventional CMOS. In adiabatic switching circuits, the current flow through transistors can be significantly reduced by ensuring uniform charge transfer over the entire available time. This paper presents the simulation of this current in two-phase clocked adiabatic static CMOS logic (2PASCL) and conventional CMOS. From the SPICE simulations, at transition frequencies from 1 to 12 MHz, a 4×4-bit array 2PASCL multiplier shows a maximum reduction in power dissipation of 77% relative to that of a static CMOS. The measurement results of a 4×4-bit array 2PASCL multiplier demonstrate a 57% reduction compared to a 4×4-bit array two-phase clocked adiabatic dynamic CMOS logic (2PADCL). These results indicate that 2PASCL technology can be advantageous when applied to low-power digital devices operated at low frequencies, such as radio-frequency identification (RFID) tags, smart cards, and sensors. 相似文献
8.
Ken Saito Kazuto Okazaki Tatsuya Ogiwara Minami Takato Katsutoshi Saeki Yoshifumi Sekine Fumio Uchikoba 《Electrical Engineering in Japan》2014,186(3):43-50
This paper presents the locomotion control of a microelectromechanical system (MEMS) microrobot. The MEMS microrobot demonstrates locomotion control by pulse‐type hardware neural networks (P‐HNN). P‐HNN generate oscillatory patterns of electrical activity like those of living organisms. The basic component of P‐HNN is a pulse‐type hardware neuron model (P‐HNM). The P‐HNM has the same basic features as biological neurons, such as the threshold, the refractory period, and spatiotemporal summation characteristics, and allows the generation of continuous action potentials. P‐HNN has been constructed with MOSFETs and can be integrated by CMOS technology. Like living organisms, P‐HNN has realized robot control without using software programs or A/D converters. The size of the microrobot fabricated by MEMS technology was 4 × 4 × 3.5 mm. The frame of the robot was made of a silicon wafer, equipped with rotary actuators, link mechanisms, and six legs. The MEMS microrobot emulated the locomotion method and the neural networks of an insect by rotary actuators, link mechanisms, and the P‐HNN. We show that the P‐HNN can control the forward and backward locomotion of the fabricated MEMS microrobot, and that it is possible to switch its direction by inputting an external trigger pulse. The locomotion speed was 19.5 mm/min and the step size was 1.3 mm. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(3): 43–50, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22473 相似文献
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