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1.
An efficient algorithm is presented for numerically evaluating a self-consistent field theoretic (SCFT) model of block copolymer structure. This algorithm is implemented on a distributed memory parallel cluster in order to solve the SCFT equations on large computational grids. Simulation results are presented for a two-component molten mixture of a symmetric ABA triblock copolymer with an A homopolymer. These results illustrate a case in which simulating a large system is required to resolve features with a wide range of length scales. 相似文献
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Advances in genetic engineering and expression systems have led to a rapid progress in the development of immunoglobulins fused to other proteins. These 'antibody fusion proteins' have novel properties and include antibodies fused to the cytokine interleukin-2. In the present review we describe strategies for construction of these antibody-interleukin-2 fusion proteins and discuss their in vitro and in vivo properties. Antibody-interleukin-2 fusion proteins retain both antibody associated functions such as antigen binding, complement activation and Fc gamma receptor binding as well as interleukin-2 associated functions such as the stimulation of proliferation of CTLL2 cells. In vivo, they produce strong potentiation of the host immune response against any associated antigen. In addition, these novel molecules are able to target tumor cells and produce a specific and effective T cell response capable of eliminating the tumor. These properties suggest that antibody-interleukin-2 fusion proteins will be useful in the diagnosis and/or treatment of human cancer as well as in the potentiation of human response against any associated antigen. 相似文献
4.
The MSMIE protocol [SBC89] allows processors in a distributed system to communicate via shared memory. It was designed to meet the reliability and efficiency needs of applications such as nuclear safety systems. We present a formal model of the MSMIE protocol expressed in the notation CCS. Desirable properties of the protocol are expressed in the modal mu-calculus, an expressive modal logic. We show that the protocol lacks an important liveness property. In actual operation, additional operating constraints are checked to avoid potential problems. We present a modified protocol and show that it possesses the liveness property even without checking operating constraints. We also show how parts of the analysis were automated with the Concurrency Workbench. 相似文献
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The influence of school- and age-related variables was examined separately on 2 tasks involving elementary quantitative skills: conservation of number and mental addition. Performance on these tasks was compared by using a cutoff design with 3 groups of kindergarten and Grade 1 children who differed in age but not amount of schooling (grade), in schooling but not age, or in both age and schooling. The effects of age and schooling were distinct. On conservation of number, performance improved as a function of age but not schooling. On mental arithmetic, accuracy improved with schooling rather than age but children's use of various solution procedures (e.g., retrieval, counting) was not influenced by schooling. Thus, in the domain of elementary mathematical skills, the influence of schooling can be very specific, and age-related variables other than schooling play an important role in the development of elementary mathematical skills. Results illustrate the utility of the cutoff design for investigating instructional and developmental influences on cognitive development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Timothy G. Trucano Dennis E. Grady Glenn D. Kubiak Marlin E. Kipp Richard E. Olson Archie Farnsworth 《International Journal of Impact Engineering》1995,17(4-6):873-890
xtreme
ltra
iolet
ithography (EUVL) seeks to apply radiation in a wavelength region centered near 13 nm to produce microcircuits having feature sizes 0.1 micron or less. A critical requirement for the commercial application of this technology is the development of an economical, compact source of this radiation which is suitable for lithographic applications. A good candidate is a laser-plasma source, which is generated by the interaction of an intermediate intensity laser pulse (up to 1012 W/cm2) with a metallic target. While such a source has radiative characteristics which satisfy the needs of an EUVL source, the debris generated during the laser-target interaction strikes at the economy of the source. Here, we review the use of concepts and computer modeling, originally developed for hypervelocity impact analysis, to study this problem. 相似文献
8.
Prior work has focused on the negative aspects of time-dispersive channels and associated intersymbol interference. The authors show that the inherent diversity introduced by such dispersion is advantageous in reducing the performance-limiting effects of flat fading. This is demonstrated for an indoor QPSK radio link employing a decision-feedback equaliser 相似文献
9.
Youngjohn James R.; Larrabee Glenn J.; Crook Thomas H. 《Canadian Metallurgical Quarterly》1992,4(1):54
The authors attempt to provide a better understanding of the differences between the normal memory decline characteristic of age-associated memory impairment (AAMI) and the pathological decline typical of mild Alzheimer's disease (AD). Batteries of traditional memory tests and computer-simulated everyday-memory tests discriminated between the 2 groups, which were matched on age, gender, and education, with reasonable degrees of accuracy (87.5% and 88.4%, respectively). False positives were the most frequent classification errors when using either battery. These results indicate that it is possible to use ecologically valid memory assessment paradigms without sacrificing discriminant validity. The clinical significance of discriminating mild AD from AAMI is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Amjad B. Soulaka William R. Morrison 《Journal of the science of food and agriculture》1985,36(8):709-718
Starches isolated from 23 bread wheats (Triticum aestivum) and 26 durum wheats (T. durum) contained 26.3-30.6% (mean 29.1%) total amylose, 19.3–25.1% (mean 22.9%) apparent amylose and 783–1144mg 100g?1 (mean 977 mg 100g?1) lysophos-pholipids. Gelatinisation temperatures were 57.3–64.9°C (mean 61.8°C) and enthalpies 6.4–11.8 Jg?1 (mean 9.7Jg?1) in excess water, measured by differential scanning calorimetry. There were no correlations between any of these parameters. Starch granule size distributions were determined with a Coulter Counter and 100–channel analyser. A-granule mean volumes were 1235–2585μm3 (av. 1778), modal volumes 863–1804μm3 (av. 1264), mean diameters 13.9–16.0μm (av. 13.99), and specific surface areas 0.236–0.302m2g?1. B-granule mean volumes were 35.4–100.4μm3 (av. 55.9), modal volumes 16.5–54.5μm3 (av. 27.7), mean diameters 3.66–5.07μm (av. 4.09), and specific surface areas 0.684–0.920m2g?1. The B-granule contents of the starches were 12.8–34.6% (av. 27.3) by weight (sedimentation method) and 13.0–37.3% (av. 24.0) by volume (Coulter method), the latter being the more accurate method. 相似文献