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111.
A reconfigurable antenna is attractive for advanced wireless communication systems in the future. A novel polarisation switchable slot-ring array antenna as a kind of reconfigurable antenna is proposed. To realise the orthogonal polarisation switchable antenna, four switching diodes are mounted on a slot-ring antenna element. The both-sided MIC technology is effectively employed in forming this slot-ring array antenna. The Ansoft HFSS is used to simulate the antenna, and the characteristics of this functional antenna are discussed. The calculated results are compared with the measured ones, and these results agree well. Consequently, a readability of the polarisation switchable antenna is successfully verified.  相似文献   
112.
Effect of dietary β-carotene supplementation (7500 mg/head/day) for 28 days prior to slaughter on beef color stability during display of M. semimembranosus (SM) and M. longissimus lumborum (LL) from Japanese Black steers was studied. Steak samples from two muscles were over-wrapped with PVC film and displayed under fluorescent lights at 4°C for 12 days. Metmyoglobin percentages of steak samples were determined at days 0, 3, 6, 9 and 12. The β-carotene concentration in both muscles was increased (P<0.001) by dietary β-carotene supplementation. Color display-life of muscles was calculated by the metmyoglobin threshold method based on a threshold value of 20% metmyoglobin. Color display-lives of SM and LL were extended 1.5 and 3 days by dietary β-carotene supplementation, respectively.  相似文献   
113.
Mold species that grew on the surface of retailed strawberries (10 packs, 211 strawberries) and cherries (18 packs, 441 cherries) during storage at 25 degrees C were isolated and identified to evaluate the state of mold growth. Mold growth was observed on 208 (98.6%) of the 211 strawberries and 193 (43.8%) of the 441 cherries. The mold species most frequently isolated from strawberries was Botrytis cinerea, being observed in 81.0% of the strawberries examined, followed by Cladosporium and Alternaria alternata. The mold most frequently isolated from cherries was Alternaria (28.7%), followed by Penicillium, Botrytis, and Cladosporium. The frequency of cherries on which mold growth was observed varied among packs. Mold tended to grow more often in the areas of the fruits in contact with adjacent fruits.  相似文献   
114.
A novel three-dimensional (3-D) masterslice monolithic microwave integrated circuit (MMIC) is presented that significantly reduces turnaround time and cost for multifunction MMIC production. This MMIC incorporates an artificial ground metal for effective selection of master array elements on the wafer surface, resulting in various MMIC implementations on a master-arrayed footprint in association with thin polyimide and metal layers over it. Additionally, the 3-D miniature circuit components of less than 0.4 mm2 in size provide a very high integration level. To clearly show the advantages, a 20-GHz-band receiver MMIC was implemented on a master array with 6×3 array units including a total of 36 MESFETs in a 1.78×1.78 mm area. Details of the miniature circuit components and the design, closely related to the fabrication process, are also presented. The receiver MMIC exhibited a 19-dB conversion gain with an associated 6.5-dB noise figure from 17 to 24 GHz and an integration level four times higher than conventional planar MMICs. This technology promises about a 90% cost reduction for MMIC because it can be similarly applied to large-scale Si wafers with the aid of an artificial ground  相似文献   
115.
This paper describes the performance of a 256 QAM modem with 400 Mbit / s transmission capacity. A variety of novel techniques are introduced as ways to achieve good performance. Key techniques include 1) an accurate 256 QAM modulator employing a new monolithic multiplier IC, 2) a carrier recovery circuit which satisfies such requirements: good phase jitter performance and no false lock phenomenon, 3) a highly stable high-level decision circuit, and 4) a forward error correcting code. As an overall modem performance, BER characteristics and signatures are presented. The equivalent CNR degradations of 1 dB(at BER of 10-4) and 2 dB (at BER of 10-9)are obtained using a single Lee-error correcting code and a seven-tap baseband transversal equalizer. The residual bit errors are decreased below the order of 10-10. The performance of a 256 QAM multicarrier modem has given prospect for the development of 400 Mbit/s digital microwave radio system.  相似文献   
116.
It is known that space flight affects T lymphocyte function in both humans and animals, but there have been no papers dealing with the effect of microgravity conditions for a very short time (i.e., only 10 s). In the present study, the effect of very short time microgravity on the cytotoxicity and surface markers of human activated T lymphocytes, in vitro, was investigated using the drop-shaft type of microgravity experiment system. The levels of heat shock protein 60 and 70 (hsp60 and hsp70) were also quantified in cells exposed to these microgravity conditions. The results showed that not only the cytotoxicity but also the hsp60 levels were remarkably reduced under these conditions.  相似文献   
117.
Efficacy of standard regimens (e.g., 3-6 MU for 24 weeks) of alfa-IFN therapy for chronic hepatitis C has been limited, particularly in patients with HCV/1b. To see if higher-dose longer term treatment is more effective, we tried a 9 MU 60-week regimen. HCV/1b-infected chronic hepatitis patients received 9 MU IFN alpha 2a everyday but Sunday for 2 weeks and thrice a week for next 10 weeks, and 76 patients became HCV RNA-negative while 81 remained positive. The RNA-negative patients were then randomized to receive 3 MU (group I, n = 37) or 9 MU (group II, n = 39) for 48 weeks. Of the RNA-positive patients, only those with normal ALT received another 9 MU 48-week treatment (group III, n = 45). Sustained responders (SR) were defined as those with negative RNA and normal ALT 6 months after the therapy. SR rates based on intent-to-treat principle did not differ significantly between groups I and II (30% vs 41%), but those based on the protocol-compatible cases showed a significantly lower than those in group II. Adverse effects of IFN, developed more frequently in groups II and III than in group I, were mostly reversible. In conclusion, our results encourage 9 MU 60-week IFN alpha treatment in HCV/1b-infected patients with careful attention to adverse effects, and suggest that the treatment should be discontinued if HCV RNA does not disappear within 12 weeks.  相似文献   
118.
A non-covalently coimmobilized bienzymic reactor of horseradish peroxidase (HRP) and cholesterol oxidase (COD), operating in a continuous organic flowing stream of 1X10-3 M p-anisidine in buffer-saturated (pH 7.0) toluene, has been employed for cholesterol determination in animal greases, such as pig, beef, and chicken fat, and codfish liver oil. The method provides a good linear relationship up to 1.8 X 10-3 M cholesterol and average recoveries of 99.5%, a high sensitivity, with a detection limit of 1 X 10-6 M of cholesterol and a good precision (an interday RSD of 1.8% for the determination of total cholesterol in a codfish oil sample). The method permits the direct spectrophotometric determination of free cholesterol present in animal grease samples without any pre-treatment, and the total cholesterol determination after a microwave-assisted saponification. The bienzymic reactor exhibits a good stability in the water-restricted environment, being possible to perform more than 180 analyses during a period of 10d with 1mg of HRP, and 1 mg of COD, equivalent to 220 purpurogallin units and 23 U, respectively.  相似文献   
119.
An FET-sized 1-18-GHz monolithic active magic T (180° hybrid) is proposed. It unifies two different dividers, electrically isolated from each other, in a GaAs FET electrode configuration; this is the line unified FET (LUFET) concept. Its characteristics and experimental results are presented. Applications of the magic T to miniature wideband RF signal processing modules such as dividers, combiners, and switches are described  相似文献   
120.
Administration of platelet-activating factor (PAF) to perfused adrenal increased cortisol and corticosterone secretion. With hexadecyl PAF (C16PAF; 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine), the increase was significant at 1 nM and maximal at 10 nM. The responses to 10 nM octadecyl PAF (C18PAF; 1-O-octadecyl-2-acetyl-sn-glycero-3-phosphocholine) were one fourth of those to 10 nM C16PAF. The addition of C16PAF to dispersed adrenal cells significantly increased cortisol and corticosterone production at 0.1 nM and 10 nM, respectively. C16PAF was about 1000 times more potent than histamine on a molar basis in respect to cortisol response in both perfused adrenal and dispersed adrenal cells. The results suggest that PAF induces cortisol release from dog adrenal. Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989. The present data were also reported at the VIIth International Congress on Hormonal Steroids, Madrid, Spain, September, 1986 (J. Steroid Biochem. 25, 76S, 1986, Abstract).  相似文献   
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