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81.
Johnson M. Al-Shamma A. Bosch D. Crowley M. Farmwald M. Fasoli L. Ilkbahar A. Kleveland B. Lee T. Tz-yi Liu Quang Nguyen Scheuerlein R. So K. Thorp T. 《Solid-State Circuits, IEEE Journal of》2003,38(11):1920-1928
A 512-Mb one-time-programmable memory is described, which uses a transistorless two-terminal memory cell containing an antifuse and a diode. Cells are fabricated in polycrystalline silicon, stacked vertically in eight layers above a 0.25-/spl mu/m CMOS substrate. One-time programming is performed by applying a high voltage across the cell terminals, which ruptures the antifuse and permanently encodes a logic 0. Unruptured antifuses encode a logic 1. Cells are arranged in 8-Mb tiles, 1 K rows by 1 K columns by 8 bits high. The die contains 72 such tiles: 64 tiles for data and eight tiles for error-correcting code bits. Wordline and bitline decoders, bias circuits, and sense amplifiers are built in the CMOS substrate directly beneath the memory tiles, improving die efficiency. The device supports a generic standard NAND flash interface and operates from a single 3.3-V supply. 相似文献
82.
OBJECTIVE: The purpose of this study was to review the results of radiologically placed subcutaneous venous access ports in a pediatric population requiring long-term venous access. CONCLUSION: Sixteen of 20 patients had no significant problems with their ports. In the pediatric population, radiologically placed subcutaneous venous access ports offer a high success rate, a low complication rate, and significant cost savings over surgically placed ports. 相似文献
83.
CK Welt G Lambert-Messerlian W Zheng WF Crowley AL Schneyer 《Canadian Metallurgical Quarterly》1997,82(11):3720-3727
Activin induces proliferation in epithelial ovarian carcinoma cell lines, whereas follistatin (FS), an activin binding protein, inhibits this action. To test the hypothesis that activin production, in excess of inhibin and FS, results in cell proliferation in epithelial ovarian tumors, messenger RNA (mRNA) expression of the activin family of proteins, FS, and activin type I and II receptors was examined in 25 primary epithelial ovarian tumors and tumor epithelium in culture (n = 7) using RT-PCR. Activin A was measured in the serum of ovarian cancer patients, and activin A, total inhibin, and FS protein secretion was measured from primary epithelial tumors in vitro. The effect of activin and FS on cell proliferation was assessed by measuring [3H]thymidine incorporation. All results were compared with normal ovarian epithelium. All epithelial ovarian tumors expressed mRNA for the alpha, beta A, and beta B subunits; FS 288 and 315; and the activin type IA, IB, II, and IIB receptors. beta A mRNA expression, as assessed using semiquantitative RT-PCR, was 3-fold greater in cultured tumor epithelium than in primary tumors (band density 0.86 +/- 0.17 vs. 0.28 +/- 0.09; P < 0.01). In addition, beta A mRNA was abundantly expressed in normal epithelium in culture (n = 2), whereas only trace amounts were seen in 2/9 primary epithelial samples. Activin protein was secreted by 24/25 primary epithelial ovarian tumors (range 0.2-155.8 ng/mL). In contrast, total inhibin was secreted by only 2/25 (range 0.01-0.92 ng/mL), whereas free FS was not detectable in the medium of any tumor (< 0.5 ng/mL). Treatment with activin or FS did not consistently affect cell growth. Measurement of serum activin A in a subset of subjects and in 27 additional subjects with epithelial ovarian carcinoma (n = 33) revealed preoperative activin A levels > 3 SD above the mean for pre- and postmenopausal women in 13/33 (39%) subjects. We conclude that in epithelial ovarian cancer: 1) beta A subunit mRNA is expressed, 2) activin protein is secreted more frequently than inhibin and in greater quantities than FS, 3) beta A subunit mRNA expression is greater in neoplastic and normal epithelium in culture than in the primary tissue, 4) the majority of tumors in culture do not respond to activin or FS treatment with proliferation, and 5) serum activin levels may reflect tumor secretion in some patients. Thus, activin A appears to be available as an autocrine/paracrine factor in epithelial ovarian tumors and may contribute to circulating levels, but its role in tumorigenesis has yet to be defined. 相似文献
84.
85.
Two correlated problems, rampant escalation of health-care costs and the lack of access to health care for many Americans, challenge long-term solutions to our health-care crisis. Historically, free markets have provided the most effective method of controlling costs. Although the current health-care system is highly competitive, it falls far short of being a truly competitive marketplace emphasizing competition around cost and quality. A health-care system based on managed competition in which the marketplace is structured to create competition on cost and quality provides great promise for regulating health costs. Erosion of health-care benefits under our current system of employer-based health insurance threatens the effectiveness of any market-based solution. The 21st Century Health Care Act combines the cost-effectiveness and universal access derived through a single revenue spigot with the power of a market approach created by managed competition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
L Vincent R Lamrini P Pommier I Martel S Helfre C Carrie 《Canadian Metallurgical Quarterly》1997,53(6):360-361
Cardiotoxicity is not a well-known complication of the administration of vinorelbine (Navelbine). We report a case of cardiogenic shock with pulmonary edema after administration of vinorelbine within an association of radiotherapy and chemotherapy. 相似文献
87.
James L. Crowley 《Robotics and Autonomous Systems》1997,19(3-4):347-358
Computer vision provides a powerful tool for the interaction between man and machine. The barrier between physical objects (paper, pencils, calculators) and their electronic counterparts limits both the integration of computing into human tasks, and the population willing to adapt to the required input devices. Computer vision, coupled with video projection using low cost devices, makes it possible for a human to use any convenient object, including fingers, as digital input devices. In such an “augmented reality”, information is projected onto ordinary objects and acquired by watching the way objects are manipulated. In the first part of this paper we describe experiments with techniques for watching the hands and recognizing gestures.
Vision of the face is an important aspect of human-to-human communication. We have been experimenting with the use of computer vision “watch the face”. In the second part of this paper we describe techniques for detecting, tracking and recognizing faces. When combined with real time image processing and active control of camera parameters, these techniques can greatly reduce the communications bandwidth required for videophone and videoconference communications. 相似文献
88.
89.
David Tall Eddie Gray Maselan Bin Ali Lillie Crowley Phil DeMarois Mercedes McGowen 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(1):81-104
Abstract: Symbols occupy a pivotal position between processes to be carried out and concepts to be thought about. They allow us both to do mathematical problems and to think about mathematical relationships. In this article we consider the discontinuities that occur in the learning path taken by different students, leading to a divergence between conceptual and procedural thinking. Evidence will be given from several different contexts in the development of symbols through arithmetic, algebra, and calculus, then on to the formalism of axiomatic mathematics. This evidence is taken from a number of research studies recently conducted for doctoral dissertations at the University of Warwick by students from the United States, Malaysia, Cyprus, and Brazil, with data collected in the United States, Malaysia, and the United Kingdom. All the studies form part of a broad investigation into why some students succeed, while others fail. 相似文献
90.
White Carrie V.; Pascarella Ernest T.; Pflaum Susanna W. 《Canadian Metallurgical Quarterly》1981,73(5):697
30 learning-disabled Hispanic, White, and Black children (mean IQ 88.60 and mean age 11.73 yrs) were randomly assigned to 2 conditions focusing on sentence comprehension: a sentence anagram/word grouping treatment and a more traditional sentence study treatment. With age, IQ, and pretest comprehension (Gates-MacGinitie Reading Tests) controlled, Ss in the sentence anagram/word grouping condition had significantly higher cloze scores than Ss in the sentence study group. The greatest achievement benefits associated with the anagram treatment, however, accrued to Ss with higher initial reading achievement. As level of pretreatment achievement decreased, the magnitude of the treatment differences also tended to decrease. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献