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Ohne ZusammenfassungMitteilung aus der Versuchsstation für Molkereiwesen in Kiel.  相似文献   
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Ohne ZusammenfassungMitteilung aus dem Laboratorium der Veruchsstation und Lehranstalt für Molkereiwesen in Kiel. Referent: A. Burr.  相似文献   
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One major assumption in all orthogonal space-time block coding (O-STBC) schemes is that the channel remains static over the entire length of the codeword. However, time selective fading channels do exist, and in such case the conventional O-STBC detectors can suffer from a large error floor in the high signal-to-noise ratio (SNR) cases. This paper addresses such an issue by introducing a parallel interference cancellation (PIC) based detector for the G/sub i/ coded systems (i=3 and 4).  相似文献   
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We report on the experimental realization of a simple optical comb generator, based on phase modulation within an amplified fiber loop, which offers exact referencing to an arbitrary supplied reference frequency and tunable comb-line spacing. At a reference wavelength of 1529 nm up to 103 comb lines within a 40-dB power envelope were generated with spacings adjustable from 1 to 25 GHz, limited only by the bandwidth of the phase modulator  相似文献   
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BACKGROUND: It has already been shown that the production of fucosylceramide, an aberrant glycolipid, is associated with neoplastic changes in human tissues. The authors of this study designed a sandwich radioimmunoassay (RIA) using a mouse monoclonal anti-fucosylceramide antibody, PC47H, designated as PC/PC RIA, and measured the level of u-FCC, an antigen of PC47H, in the urine of cancer patients. METHODS: The cohort comprised 41 patients with gastric carcinoma, 35 with colorectal carcinoma, 34 with other malignancies, 14 with cholelithiasis, 18 with gastric ulcer, and 110 healthy individuals. The u-FCC was quantified by PC/PC RIA. The cutoff value of u-FCC was obtained from the 110 healthy individuals, and the rates of positivity for gastric and colorectal carcinoma patients were evaluated. RESULTS: The rates of u-FCC positivity were 63% for patients with gastric carcinoma and 69% for colorectal carcinoma patients. The rate was only 1% (1/110) for the healthy individuals. The u-FCC value did not correlate with the values of either CA 19-9 or carcinoembryonic antigen (CEA). In a combination assay of u-FCC with CA 19-9 and CEA, the positivity rates were 84% for gastric carcinoma patients and 85% for colorectal carcinoma patients. CONCLUSIONS: Gastric and colorectal carcinoma patients have significantly high levels of u-FCC in their urine compared with normal individuals.  相似文献   
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A parallel interference cancellation (PIC) detection scheme is proposed to suppress the impact of imperfect synchronisation. By treating as interference the extra components in the received signal caused by timing misalignment, the PIC detector not only offers much improved performance but also retains a low structural and computational complexity  相似文献   
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"The achievement of students enrolled in elementary psychology and biology television instruction and non-television instruction was compared. No significant differences were found. An audience-reaction survey of Houston televiewers revealed that 75% of the audience watched the station from as often as three times a week to at least once in two weeks. Highly preferred programs included sports, a psychology course, and an international affairs discussion panel. Suggested programs ranked most highly were sports programs, educational films, panel discussion, and children's programs. Least preferred programs were of the classical music type." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Magnetic susceptibility measurements have been made on dilute monocrystalline alloys MgDy, MgNd, and MgCe. At low temperatures these alloys are anisotropic, which enables an evaluation of the crystalline electric field. A computer program was written to make a chi-square fit to these data and obtain the crystalline field parameters, which are compared to those derived from EPRg values for MgEr alloys.Supported in part by a State University of New York Research Foundation Award.  相似文献   
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