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261.
The activities of chymotrypsin-like esteroproteases in the mouse submandibular gland were additively induced by 5 alpha-dihydrotestosterone (DHT) and triiodothyronine (T3). Zymograms showed that there are many isozymes whose activities are regulated by DHT and/or T3. Some isozymes seemed to be hormone-independent. Histochemical studies revealed that all these isozymes are localized in the granular convoluted tubules.  相似文献   
262.
It has been reported that the flashover voltage of gaseous dielectrics may increase greatly when they are mixed with carbon-halide mist. However, the factors which bring about the increase of the flashover voltage still are not clarified fully. Based on the study on the basic flashover characteristics of vapor-mist dielectrics, the authors have suggested the scarcity of initial electrons as the predominant factor. This paper investigates further the effect of UV light irradiation, flashover characteristics under forced supply of initial electrons, and for lightning impulse superimposed on dc voltage. These results have verified that the scarcity of initial electrons is the decisive factor in increasing the lightning impulse flashover voltage of vapor-mist dielectrics. It is clarified also that the scarcity is attributed principally to: (1) the reduction of effective period (lifetime) of initial electrons, and (2) the suppression of photoelectric emission from electrodes.  相似文献   
263.
The establishment of an early trouble diagnosis system is needed in order to prevent damage to wind turbine generators. Therefore, acoustic emission (AE) signals resulting from damage to a wind blade were detected with an AE sensor installed on the body of the wind turbine generator and on the mounting pole. In this study, the length of a blade of a micro wind turbine generator was varied to simulate trouble at constant wind velocity. The AE signals which occurred at this time were measured with an AE sensor. The signal was processed by FFT analysis, and the change of spectral strength was examined. A trouble diagnosis technology for 50‐W‐grade micro wind turbines generator was then developed. A method of counting the number of occurrences of above‐threshold AE signals was suggested by the wave pattern of the AE signals. It was found that the number of occurrences could be used as a standard to judge the normality or abnormality of 50‐W‐grade micro wind turbine generators. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(1): 33–39, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21017  相似文献   
264.
Mesoporous silica nanospheres with an average diameter of approximately 240 and 600 nm have been used as catalyst supports of active Pt nanoparticles, which were found to be highly efficient for liquid-phase hydrogenation under atmospheric H2 compared to the micron-sized conventional mesoporous silica because of the suppression of mass-transport limitation toward active sites.  相似文献   
265.
Dynamic drop test for studying the temporal lowering of hydrophobicity on the surface of silicone rubber with direct current voltage application was carried out. In this study, we evaluated the influence of the temporal lowering of hydrophobicity under various conductivities and dropping rates for water droplets. As a result, it was found that the dropping rate and the conductivity of water droplets greatly influenced the hydrophobicity loss time on the surface of silicone rubber.  相似文献   
266.
The liver directly accepts blood from the gut and is, therefore, exposed to intestinal bacteria. Recent studies have demonstrated a relationship between gut bacteria and nonalcoholic fatty liver disease (NAFLD). Approximately 10–20% of NAFLD patients develop nonalcoholic steatohepatitis (NASH), and endotoxins produced by Gram-negative bacilli may be involved in NAFLD pathogenesis. NAFLD hyperendotoxicemia has intestinal and hepatic factors. The intestinal factors include impaired intestinal barrier function (leaky gut syndrome) and dysbiosis due to increased abundance of ethanol-producing bacteria, which can change endogenous alcohol concentrations. The hepatic factors include hyperleptinemia, which is associated with an excessive response to endotoxins, leading to intrahepatic inflammation and fibrosis. Clinically, the relationship between gut bacteria and NAFLD has been targeted in some randomized controlled trials of probiotics and other agents, but the results have been inconsistent. A recent randomized, placebo-controlled study explored the utility of lubiprostone, a treatment for constipation, in restoring intestinal barrier function and improving the outcomes of NAFLD patients, marking a new phase in the development of novel therapies targeting the intestinal barrier. This review summarizes recent data from studies in animal models and randomized clinical trials on the role of the gut–liver axis in NAFLD pathogenesis and progression.  相似文献   
267.
ABSTRACT

The present paper introduces a near-future perception system called Previewed Reality. In a co-existence environment of a human and a robot, unexpected collisions between the human and the robot must be avoided to the extent possible. In many cases, the robot is controlled carefully so as not to collide with a human. However, it is almost impossible to perfectly predict human behavior in advance. On the other hand, if a user can determine the motion of a robot in advance, he/she can avoid a hazardous situation and exist safely with the robot. In order to ensure that a user perceives future events naturally, we developed a near-future perception system named Previewed Reality. Previewed Reality consists of an informationally structured environment, a VR display or an AR display, and a dynamics simulator. A number of sensors are embedded in an informationally structured environment, and information such as the position of furniture, objects, humans, and robots, is sensed and stored structurally in a database. Therefore, we can forecast possible subsequent events using a robot motion planner and a dynamics simulator and can synthesize virtual images from the viewpoint of the user, which will actually occur in the near future. The viewpoint of the user, which is the position and orientation of a VR display or an AR display, is also tracked by an optical tracking system in the informationally structured environment, or the SLAM technique on an AR display. The synthesized images are presented to the user by overlaying these images on a real scene using the VR display or the AR display. This system provides human-friendly communication between a human and a robotic system, and a human and a robot can coexist safely by intuitively showing the human possible hazardous situations in advance.  相似文献   
268.
Heavy metals such as zinc are widely used in plating plants for the processing of material surfaces; therefore, an adequate wastewater treatment is required afterwards to comply with wastewater regulations. However, the presence of chemicals such as degreasing agents in the wastewater generated from the plating process inhibits the formation of hydroxides, thereby making treatment of wastewater and compliance with the stipulated regulations difficult. Herein, the effects of fine bubbles on oil cleaning and wastewater treatment were investigated for developing an alternative cleaning technology to degreasing agents. The concentration of fine bubbles significantly affected the oil cleaning. The fine bubbles demonstrated remarkable cleaning of highly viscous oil, which was difficult to remove using pure water. The high cleaning effect of fine bubbles on oil was achieved because of the hydrophobic interaction of the bubbles. Furthermore, a decrease in cleaning effect was observed for samples with uneven shapes, which was attributed to the difficulty in penetration of fine bubbles in materials with irregularities. Furthermore, fine bubble cleaning exhibited better efficiency for wastewater treatment than degreaser cleaning. Therefore, fine bubble cleaning is speculated to be an excellent cleaning technology with high oil cleaning effectiveness and improved wastewater treatability.  相似文献   
269.
In this study, the yield stress and fracture strength of β $\ubeta$ -Si3N4 single crystals were directly measured by bending tests of microcantilever beam specimens that were prepared by a focused ion beam method. The β $\ubeta$ -Si3N4 single crystals were plastically deformed at room temperature under high bending stress, and the yield stress depended on the crystal orientation. Transmission electron microscopy observation of the specimens after bending tests indicates that the plastic deformation resulted from dislocations in the primary slip system { 10 1 ¯ 0 } $\{ 10\bar{1}0\} $ <0001>, and the critical resolved shear stress of this slip system determined from the yield stress was 1.34 GPa. The fracture strength of β $\ubeta$ -Si3N4 single crystals ranged approximately up to 20 GPa, depending on the crystal orientation as with the yield stress. The fracture behavior of β $\ubeta$ -Si3N4 single crystals was discussed in terms of the accumulation of dislocations.  相似文献   
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