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101.
This paper considers partial-column radix-2 FFT processors and realizations of butterfly operations. The area and power-efficiency
of butterfly units to be used in the proposed processor organization based on bit-parallel multipliers, distributed arithmetic,
and CORDIC are analyzed and compared. All the selected butterfly units are synthesized onto the same 0.11 μ ASIC technology
allowing the results to be compared. The proposed processor organization permits the area of the FFT implementation to be
traded against the computation time, thus the final structure can be easily tailored according to the requirements of the
given application. The power consumption comparison shows that butterflies based on bit-parallel multipliers are power-efficient
but have limitations on clock frequency. Butterflies based on distributed arithmetic could be used when higher clock frequencies
are used. If extremely long FFTs are needed, the CORDIC based butterflies are applicable.
Jarmo Takala received his M.Sc. (hons) degree in Electronics and Dr.Tech. degree in Information Technology from Tampere University of
Technology, Tampere, Finland (TUT) in 1987 and 1999, respectively. From 1992 to 1996, he was a Research Scientist at VTT-Automation,
Tampere, Finland. Between 1995 and 1996, he was a Senior Research Engineer at Nokia Research Center, Tampere, Finland. From
1996 to 1999, he was a Researcher at TUT. Currently, he is Professor in Computer Engineering at TUT and head of the Insitute
of Digital and Computer Systems of TUT. His research interests include circuit techniques, parallel architectures, and design
methodologies for digital signal processing systems.
Konsta Punkka received his M.Sc. degree (hons) in Electrical Engineering from Tampere University of Technology (TUT), in 2002. He is currently
working towards his Dr.Tech. degree as a research scientist in the Institute of Digital and Computer Systems at TUT. His research
interests include optimization and implementation of DSP architectures. 相似文献
102.
YL Kwong AC Chan R Liang AK Chiang CS Chim TK Chan D Todd FC Ho 《Canadian Metallurgical Quarterly》1997,97(4):821-829
Dosing regimen is an important determinant of both drug cost and patient compliance. This retrospective analysis evaluated dosing regimens and drug acquisition costs for 101 patients identified from medical records in a large metropolitan hospital as having hypertension and/or benign prostatic hyperplasia and receiving alpha-blocker therapy with either doxazosin or terazosin. Although once-daily administration is generally recommended for both drugs, 25 (38%) of 66 patients receiving terazosin were treated twice daily compared with 6 (17%) of 35 patients treated twice daily with doxazosin. This difference was statistically significant. The average (mean +/- SD) daily treatment cost per patient for all individuals receiving terazosin during the period of the record review was $1.68 +/- 0.60. For patients treated with doxazosin, the average was $0.96 +/- 0.65-a highly statistically significant result. If all 66 patients receiving terazosin had been converted to doxazosin at the beginning of the study, annual savings would have been $17,345.00. These results demonstrate the importance of reviewing actual dosing regimens. The fact that doxazosin could be administered to a significantly higher percentage of patients once daily rather than twice daily substantially decreased its cost relative to terazosin. A once-daily treatment regimen may also enhance patient compliance, thereby improving the chances of therapeutic success. 相似文献
103.
Interleukin 8 (IL-8), a neurophil-activating and chemotactic cytokine, is known to play a key role in the pathogenesis of a large number of neutrophil-driven inflammatory diseases. Although the cytokine is rapidly internalized at 37 degrees C with its receptors, there was no direct evidence for the ligand-induced endocytosis of the receptor or that of the interaction of receptor ligand complex at 37 degrees C. As a result, our understanding about the regulation of Il-8 induced biological response is very limited. In the present study, using FITC-IL-8 conjugate as a probe, we have demonstrated the time- and temperature-dependent endocytosis of IL-8 under fluorescent microscope. We have also shown that the bright fluorescent light on the surface of neutrophils gradually disappears and it becomes almost dark after 120 min of incubation. Monodansyl cadaverine (MDC, 900 microM), however, was found to retain the fluorescent light of FITC coupled with Il-8 on the cells. MDC and ouabain (2.5 mM) can inhibit the ligand induced endocytosis by 76% and 96%, respectively, compared to control. With respect to control, IL-8 induced biological responses e.g. IL-8 directed migration, intracellular Ca2+ release and superoxide release are significantly reduced by 77%, 94% and 76%, respectively, in presence of MDC. The study presents a direct visual evidence of the time and temperature-dependent receptor-mediated endocytosis of IL-8 which is inhibited by MDC and ouabain. This information is useful for understanding the ligand receptor interaction at 37 degrees C and may be useful for developing anti-inflammatory agents against IL-8. 相似文献
104.
105.
106.
Randomized carboxyl poly(2‐ethylhexyl acrylate) (A‐1) and randomized epoxy poly(2‐ethylhexyl acrylate) (B‐1) rubbers were synthesized in the form of liquid rubber by a solution polymerization technique. The liquid rubbers A‐1 and B‐1 were characterized by 1H NMR and IR spectroscopic analysis, non‐aqueous titration, viscosity measurements and gel permeation chromatography. The liquid rubbers A‐1 (M?n = 3900 g mol?1), B‐1 (M?n = 4100 g mol?1) and a (1:1) mixture of A‐1 and B‐1 were pre‐reacted with epoxy resin separately and the modified epoxy networks were made by curing with high temperature curing agent. The modified epoxy networks were evaluated by unnotched Izod impact testing. The morphology and toughening behaviour were analysed by scanning electron microscopy. Optimum properties were obtained with the mixture of A‐1 and B‐1. Copyright © 2003 Society of Chemical Industry 相似文献
107.
J Wiegant N Verwoerd S Mascheretti M Bolk HJ Tanke AK Raap 《Canadian Metallurgical Quarterly》1996,44(5):525-529
Synthesis of fluorochrome-modified deoxyribonucleotides has been carried out mostly by linking the fluorochrome molecule to the C-5 position of dUTP via an allylamine spacer, similar to the modification of allylamine-dUTP with the haptens biotin and digoxigenin. Recently, a new series of fluorescent nucleotides has been prepared by using an alkynyl bridge between the uracil moiety and the fluorochrome. Here we report the qualitative and quantitative analysis of fluorescence in situ hybridization results obtained on interphase cells and chromosomes with a variety of highly repetitive and single-copy DNA probes that were modified by nick translation with such alkynyl dUTPs. A qualitative comparison was made of the alkynyl dUTPs conjugated to the fluorochromes fluorescein, the cyanine dye Cy3, tetramethylrhodamine, Lissamine and Texas Red. With the exception of tetramethylrhodamine, all fluorochromes performed satisfactorily. The cyanine dye Cy3 provided the highest sensitivity, i.e., cosmid and YAC probes could easily be visualized by conventional fluorescence microscopy. In a quantitative assay, different nick translation conditions were tested using a human chromosome 1 satellite III probe (pUC1.77) and alkynyl dUTPs labeled with fluorescein and Cy3. Using these two nucleotides, FISH signal intensities on interphase nuclei from human lymphocytes were quantitated by digital imaging microscopy. The strongest signals were obtained when during nick translation the ratio between dTTP and fluorescein-dUTP or Cy3-dUTP was 1:5. 相似文献
108.
The gastric brushings (GBRs) and endoscopic biopsies obtained concurrently from 27 patients in whom malignant lymphoma was diagnosed or suggested by either modality were assessed to evaluate the utility of cytologic examination in the diagnosis of gastric lymphoma. GBRs provided a definitive diagnosis of lymphoma in 2 (28%) of 7 patients with a prior history of lymphoma and 10 (56%) of 18 patients with primary gastric lymphoma, yielding an overall sensitivity of 48%. All the lymphomas diagnosed cytologically were large cell type. GBRs were suspicious for a malignant neoplasm in four lymphoma patients whose concurrent biopsies were negative. GBRs obtained from two patients who had gastritis were reported as suspicious for lymphoma. There were no false-positive diagnoses. 相似文献
109.
Functional maxillofacial rehabilitation following tumor ablation depends on many variables. These include the magnitude of hard or soft tissue defects, the use of adjunctive chemotherapy or radiation therapy, and the presence of underlying systemic disease. The physiologic effects of tumor ablation and radiation therapy on local tissues and grafted bone are discussed in this article in relation to the ultimate use of implant supported prostheses. Cases are presented to illustrate a variety of clinical situations. 相似文献
110.
AK Akerberg HG Liljeberg YE Granfeldt AW Drews IM Bj-orck 《Canadian Metallurgical Quarterly》1998,128(3):651-660
The purpose of this work was to develop a method for measurement of the major forms of resistant starch (RS) in foods. The analytical procedure was chosen to mimic physiologic conditions, and included chewing as a prestep before incubation with pepsin, pancreatin and amyloglucosidase. The undigestible polysaccharides, including RS, were recovered by ethanol precipitation and subsequent filtration. RS was analyzed as total starch in the filter residue. The residues were also used for gravimetric determination of dietary fiber after correcting for remaining protein, ash and RS. The potentially available starch fraction was determined from analysis of glucose in the filtrate. The foods included were prepared to resemble products for which RS figures were available from in vivo measurements, and/or from analysis with other current in vitro methods. For six of these foods, and for three additional starchy materials, RS figures were compared with in vivo and/or in vitro data for identical products. The pooled standard deviation for the suggested RS method was 2.9%. A high correlation was obtained with in vivo figures from the literature for 19 realistic foods (r = 0.97; y = 0.77x + 0.45). After correction for RS, dietary fiber figures corresponded well with conventional gravimetric dietary fiber analysis for 14 starchy foods (r = 0.97). It is concluded that the procedure described here provides a convenient way to estimate RS content of realistic foods, allowing parallel determination of the potentially available starch fraction and dietary fiber. 相似文献