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951.
Yingsha Liao 《Automated Software Engineering》1994,1(1):11-29
In this paper, we examine the problem of generating instrumentation that efficiently computes derived performance data of program execution. The instrumentation computes these derived data at run time as the directly accessible data is collected. It tests conditions defined on the collected data and eliminates the data that does not satisfy the stated conditions, thus, avoiding recording irrelevant data. We examine this problem in terms of generating instrumentation for computing the answers to monitoring questions. Our solution is based on the use of temporal conditions defined on the events in the questions to determine which data to record and to be used as relevant run time filters on the events producing that data. 相似文献
952.
Maximizing multiprocessor performance with the SUIF compiler 总被引:1,自引:0,他引:1
Hall M.W. Anderson J.M. Amarasinghe S.P. Murphy B.R. Shih-Wei Liao Bu E. 《Computer》1996,29(12):84-89
This article describes automatic parallelization techniques in the SUIF (Stanford University Intermediate Format) compiler that result in good multiprocessor performance for array-based numerical programs. Parallelizing compilers for multiprocessors face many hurdles. However, SUIF's robust analysis and memory optimization techniques enabled speedups on three fourths of the NAS and SPECfp95 benchmark programs 相似文献
953.
F Liao RL Rabin JR Yannelli LG Koniaris P Vanguri JM Farber 《Canadian Metallurgical Quarterly》1995,182(5):1301-1314
Mig is a chemokine of the CXC subfamily that was discovered by differential screening of a cDNA library prepared from lymphokine-activated macrophages. The mig gene is inducible in macrophages and in other cells in response to interferon (IFN)-gamma. We have transfected Chinese hamster ovary (CHO) cells with cDNA encoding human Mig and we have derived CHO cell lines from which we have purified recombinant human Mig (rHuMig). rHuMig induced the transient elevation of [Ca2+]i in human tumor-infiltrating T lymphocytes (TIL) and in cultured, activated human peripheral blood-derived lymphocytes. No responses were seen in human neutrophils, monocytes, or Epstein-Barr virus-transformed B lymphoblastoid cell lines. rHuMig was chemotactic for TIL by a modified Boyden chamber assay but rHuMig was not chemotactic for neutrophils or monocytes. The CHO cell lines, IFN-gamma-treated human peripheral-blood monocytes, and IFN-gamma-treated cells of the human monocytic cell line THP-1 all secreted multiple and identical HuMig species as revealed by SDS-PAGE. Using the CHO-derived rHuMig, we have shown that the species' heterogeneity is due to proteolytic cleavage at basic carboxy-terminal residues, and that the proteolysis occurs before and not after rHuMig secretion by the CHO cells. The major species of secreted rHuMig ranged from 78 to 103 amino acids in length, the latter corresponding to the full-length secreted protein predicted from the HuMig cDNA. Carboxy-terminal-truncated forms of rHuMig were of lower specific activity compared to full-length rHuMig in the calcium flux assay, and the truncated species did not block the activity of the full-length species. It is likely that HuMig plays a role in T cell trafficking and perhaps in other aspects of the physiology of activated T cells. 相似文献
954.
A Sund?s-Larsson M Svenson H Liao P Engstr?m 《Canadian Metallurgical Quarterly》1998,95(25):15118-15122
Many homeobox genes control essential developmental processes in animals and plants. In this report, we describe the first cDNA corresponding to a homeobox gene isolated from a gymnosperm, the HBK1 gene from the conifer Picea abies (L.) Karst (Norway spruce). The sequence shows distinct similarities specifically to the KNOX (knotted-like homeobox) class of homeobox genes known from different angiosperm plants. The deduced amino acid sequence of HBK1 is strikingly similar within the homeodomain (84% identical) to the maize gene Knotted1 (Kn1), which acts to regulate cell differentiation in the shoot meristem. This similarity suggested that the phylogenetic association of HBK1 with the KNOX genes might be coupled to a conservation of gene function. In support of this suggestion, we have found HBK1 to be expressed in the apical meristem in the central population of nondifferentiated stem cells, but not in organ primordia developing at the flanks of the meristem. This pattern of expression is similar to that of Kn1 in the maize meristem. We show further that HBK1, when expressed ectopically in transgenic Arabidopsis plants, causes aberrations in leaf development that are similar to the effects of ectopic expression of angiosperm KNOX genes on Arabidopsis development. Taken together, these data suggest that HBK1 has a role, similar to the KNOX genes in angiosperms, in the control of cellular differentiation in the apical meristem of spruce. The data also indicate that KNOX-gene regulation of vegetative development is an ancient feature of seed plants that was present in the last common ancestor of conifers and angiosperms. 相似文献
955.
采用扫描电镜的ECP技术分析人工合成金刚石晶体中的晶体缺陷 总被引:1,自引:1,他引:0
本文应用扫描电镜的ECP技术对人造金刚石晶体表面的位错密度,进行了实验分析,并同位错蚀坑分析技术的测量结果进行了比较,结果表明,如采用临界束流强度作为描述ECP本征衬度的参数,则它同位错密度间存在明显定量的数学关系,因此上述临界束流强度可用来评价晶体中位错密度的相对变化。 相似文献
956.
可溶高分子负载钯催化剂对于硝基苯加氢反应催化性能的研究 总被引:3,自引:1,他引:2
以醇或水溶性高分子(聚乙烯吡咯烷酮,PVP;乙基纤维素,EC;聚乙烯醇,PVA;羧甲基纤维素钠,CMCNa)为载体,制备了四种可溶高分子负载钯催化剂。无机碱的存在对反应呈明显的加速效应。在少量K2CO3存在下,EC-PdCl2和PVP-PdCl2对于硝基苯的催化加氢具有非常高的活性,最高活性>230molH2/molPd·min,即大于5150mlH2/mmolPd·min,该数值是已知文献报道的最好结果。详细考察了各种碱、K2CO3用量、溶剂以及反应温度对PVP-PdCl2催化硝基苯加氢性能的影响。 相似文献
957.
本实验研究用数字、汉字、飞机图标和几何图形比较了颜色编码、形状编码及颜色和形状双重编码的检测工效。在阴极射线管(CRT)显示器屏幕的9个固定位置(3×3矩阵)上同时显示同一形状不同颜色、同一颜色不同形状或颜色和形状都不相同的3、6或9个字符,让被试按颜色、形状或同时按颜色和形状找出一目标字符,并按压键标数字与所找字符显示位置号相同的键。每个字符在各个位置的显示概率是相等的,显示的先后次序是随机的。字符的显示、目标字符的检测时间和错误率由计算机系统程序控制,实时计算和打印记录。结果表明,就检测工效而言,颜色编码优于颜色和形状双重编码,后者又优于形状编码;目标字符的检测时间随同时显示字符的数量的增加而增长,并得到了从同时显示的3、6、9个字符中按不同特征检测目标字符的搜索一识别时间和包括按键操作在内的目标检测时间。 相似文献
958.
DJ Pinsky H Liao CA Lawson SF Yan J Chen P Carmeliet DJ Loskutoff DM Stern 《Canadian Metallurgical Quarterly》1998,102(5):919-928
PURPOSE: In a rabbit model, transposition of a muscle pedicle flap to an ischemic hind limb has been shown to result in the development of new blood vessels that connect the arterial circulation of the flap to the circulation of the limb. The hypothesis that exogenous recombinant basic fibroblast growth factor (bFGF) would enhance the development of this new blood supply was examined and the regulation of bFGF in this process was investigated. METHODS: The right common iliac artery was ligated in 12 male New Zealand white rabbits. An abdominal wall muscle flap based on the left inferior epigastric artery was transposed to the right thigh. bFGF in phosphate-buffered saline (PBS) at 3 ng/h (n = 6), or PBS alone (n = 6), was infused for 7 days via mini-osmotic pumps with an infusion catheter positioned at the flap-muscle interface. The flap-muscle interface was immunostained with anti-alpha-actin antibody to determine blood vessel density (number of vessels/mm) and with anti-bFGF antibody to evaluate bFGF distribution. RNA was isolated from these sections, and polymerase chain reaction (PCR) was used to examine endogenous bFGF messenger RNA (mRNA) expression. RESULTS: Blood vessel density was significantly increased in animals receiving exogenous bFGF (22. 0 +/- 10.6 vessels/mm vs. 10.7 +/- 8.8 vessels/mm, P =.009). In the controls, neovessels were arranged in clusters with endogenous bFGF concentrated around these clusters. In bFGF-treated animals, vessels were diffusely scattered throughout the flap-limb interface, corresponding to the distribution pattern of infused bFGF. There was no difference in bFGF mRNA expression between the control and the bFGF-treated groups. CONCLUSION: Exogenous bFGF infusion significantly augmented new blood vessel development at the flap-limb interface. Endogenous bFGF was up-regulated around the newly developed microvessels in control animals, and vessel growth correlated with the diffuse distribution of exogenous bFGF, implicating bFGF as an important factor in angiogenesis. Exogenous bFGF did not affect bFGF mRNA expression, suggesting that the regulation of bFGF is not under autocrine control. 相似文献
959.
960.
The room-temperature cross sections for the Nd3+4F_{3/2} levels to the4I_{11/2} and4I_{9/2} manifolds (lower laser state and ground state, respectively) in NdP5 O14 are measured by two spectroscopic methods. A value for the largest cross section ofsigma(R_{1} - Y_{2}) = 1.7 times 10^{-19} cm2is found. The highest effective cross section, resulting from superposition of two lines at 1.051 μm, gives a laser gain per Nd ion which is about 2/3 of the maximum gain in YAG:Nd. The relative branching ratio into the4I_{11/2} and4I_{9/2} manifolds is 0.65:0.35. Comparison of the integrated cross sections with the measured lifetime for 1-percent Nd in LaP5 O14 indicates a combined efficiency <0.1 for the remaining transitions, namely radiative decay into the4I_{13/2} and4I_{15/2} manifolds and multiphonon quenching. A measurement of temperature dependence of fluorescence lifetime supports this last result. 相似文献