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981.
The skin tissue of the human head can play an electromagnetic shielding role in protecting the central organs from microwave exposure. For the electrical properties, however, the published data are for a wide range of tissues from fat (low water content) to muscle (high water content), and thus various electrical properties of the skin tissue are used for SAR calculations in a heterogeneous head model. This paper examines numerically how variations in the electrical properties of the skin tissue affect the SAR in the human head. Skin tissue properties are newly estimated from the Debye equation with two relaxation time constants, which are used to calculate the SAR in the developed heterogeneous head model for 1.5-GHz microwave exposure. The SAR details are compared with the following cases: results computed for skin having the same electrical properties as those of fat, our previously obtained results, and Furse's results on tissue properties. The effects of tissue mass densities on the SAR calculation are also examined. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(4): 66–73, 1997 相似文献
982.
This paper, by analyzing actual corporate planning procedures, proposes a method to classify management information used for decision making into several groups according to their characteristics. In order to select appropriate data as well as keep the data updated and readjusted to fit the continuously changing corporate planning environment, we emphasize the needs of information management by utilizing the classification proposed in this paper. An outline of the design concept of the data management system through the analysis of such characteristics on the actual data for planning in the oil refining industry is illustrated. 相似文献
983.
Shoichirou Taira Yasuyuki Yamasaki Kunihiko Nakashima Katsumi Mori 《Journal of the American Ceramic Society》1997,80(4):925-932
The dissolution rates of silicon nitride (Si3 N4 ) ceramics into CaOAl2 O3 SiO2 slags were investigated by using a rotating specimen method in the temperature range of 1773–1873 K. Dissolution rates in the present study increased as the revolution speed and temperature increased and decreased as the SiO2 content of the slags increased. The nitrogen content of the slags increased after the Si3 N4 ceramics had been immersed into them. The slags contained two types of nitrogen ions—N3− and CN- —because a graphite crucible was used for the experiment. N3− ions were confirmed in all the slags that were used in the present work; the CN- content was much lower than that of the N3− ions, except in the slag without SiO2 . Based on those results, Ficks law of diffusion was used to analyze the dissolution rates. The dissolution mechanism of the Si3 N4 ceramics into CaO–Al2 O3 SiO2 slags has been discussed in this paper. 相似文献
984.
Su-Jung Kim Yasuyuki Matsushita Kazuhiko Fukushima Dan Aoki Sachie Yagami Hyun-Gyun Yuk Seung-Cheol Lee 《LWT》2014
In this study, the antioxidant activity of hydrothermal extracts of different parts of watermelons (flesh, white rind, and green rind) was evaluated. Each part of the watermelons was extracted at temperatures ranging from 100 °C to 300 °C for 10, 30, or 60 min. The highest total phenol content was observed for the green rind extracted at 300 °C for 30 min with 7626.52 μg gallic acid equivalents (GAE)/g, whereas the phenol content of the untreated green rind extract was 715.15 μg GAE/g. The antioxidant activity of the watermelon parts increased with increase in treatment temperature and time. In GC–MS analysis, catechol, 4-methylcatechol, pyrogallol, and 1,2,4-benzenetriol were detected after hydrothermal extraction at 300 °C for 30 min. These results indicate that hydrothermal extraction is an efficient process for increasing the antioxidant activity of watermelon extracts. 相似文献
985.
Urinary trypsin inhibitor reduces inflammatory response in kidney induced by lipopolysaccharide 总被引:2,自引:0,他引:2
Ueki M Taie S Chujo K Asaga T Iwanaga Y Ono J Maekawa N 《Journal of Bioscience and Bioengineering》2007,104(4):315-320
Human urinary trypsin inhibitor (UTI), a serine protease inhibitor, has been widely used in Japan as a drug for patients with acute inflammatory disorders such as septic shock and pancreatitis. Lipopolysaccharide (LPS) triggers the sepsis syndrome by activating monocytes to produce proinflammatory cytokines, including tumor necrosis factor alpha (TNFalpha), which potently stimulate the activation of neutrophils. The inhibitory mechanism of UTI on the systemic inflammatory response induced by the intraperitoneal injection of LPS in the kidney is unclear. This study was undertaken to examine the inhibitory effects of UTI on renal injury associated with the systemic inflammatory response induced by LPS stimulation, with emphasis on systemic TNFalpha and the activation of neutrophils in rat kidney. The systemic inflammatory response syndrome was induced by LPS treatment. Serum and renal TNFalpha, renal cytokine-induced neutrophil chemoattractant-1 (CINC-1) and myeloperoxidase (MPO) levels, as well as renal function after LPS stimulation, were evaluated. UTI (50,000 U/kg) inhibited LPS-induced increases in the serum and renal tissue levels of TNFalpha, as well as the renal tissue levels of CINC-1 and MPO after LPS stimulation. UTI (50,000 U/kg) also inhibited the production of serum TNFalpha associated with the systemic inflammatory response syndrome induced by LPS stimulation, thereby attenuating neutrophil infiltration into renal tissues and subsequent neutrophil-mediated renal injury. These findings may have important implications in understanding the biologic functions of UTI. UTI may prove useful in protecting against acute renal injury associated with a systemic inflammatory response. 相似文献
986.
Jackin Boaz Jessie Jorissen Lode Oi Ryutaro Wakunami Koki Yamamoto Kenji Ichihashi Yasuyuki Bekaert Philippe Lafruit Gauthier 《Virtual Reality》2023,27(2):761-775
Virtual Reality - Heads-up displays that are ‘see-through’ and ‘curved’ and capable of displaying 3D contents are considered crucial for augmented reality-based navigation... 相似文献
987.
Siqian Wang Wei Hsun Hu Yasuyuki Nakamura Nanami Fujisawa Ane Eline Herlyng Mitsuhiro Ebara Masanobu Naito 《Advanced functional materials》2023,33(36):2215064
Development of tough, reusable adhesives is important, but remains a major challenge, especially in water. A tough reusable adhesive that resets entirely to its virgin condition when needed is reported using caffeic acid. Here, caffeic acid is employed as adhesive moiety to achieve such the functions due to its dual characteristics: an adhesive moiety from mussel-inspired catechol and a photo-reversible crosslink from cinnamic acid. Adhesion involves a two-step process. First, the caffeic acid-functionalized polymer is applied to the adherend, followed by UV irradiation (peak wavelength of light-emitting diode, λP: 365 nm) to form a durable pre-applied adhesive (PAA) layer through crosslinking among the caffeic acid moieties. Second, thermal activation of the PAA layer ensures repeated adhesion to a variety of adherends ( R euse- M any mode). The cyclic dimer of the caffeic acid moiety is de-crosslinked by UV irradiation at λP: 254 nm. This allows the complete removal of the adhesive residues from the adherends when the adhesive is no longer needed ( R eset- O n demand mode). Furthermore, using magnetic nanoparticles, the caffeic acid-functionalized polymer can be activated remotely under water by magnetic induction heating. This study paves the way for the rational design of bio-inspired adhesives that outperform nature using plant-derived raw materials. 相似文献