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191.
192.
MH West RE Barsley JE Hall S Hayne M Cimrmancic 《Canadian Metallurgical Quarterly》1992,37(6):1480-1488
This article is a discussion of the use of narrow-band light sources coupled with cameras equipped with band-pass filters to document patterned injuries on human skin. Several case reports are included. 相似文献
193.
We have isolated a putative serine/threonine receptor kinase gene with an expression pattern indicating that it may play a role in the stylar response to pollination. Differential display PCR was used to select tobacco mRNAs with increased accumulation following pollination. NTS16, a cDNA identified by this method, is homologous to a ca. 2.4 kb mRNA primarily expressed in pistil tissues. Levels of this mRNA increase during floral development and are further increased by pollination reaching maximal accumulation 12-18 hours after pollination and then declining. mRNA levels can also be increased by the application of ethylene to unpollinated flowers. A polypeptide encoded by the NTS 16 open reading frame has sequence similarity to the catalytic domain of several receptor protein kinases from plants including the S-receptor kinases implicated in the rejection of self-pollen in Brassica species and the Pto gene product of tomato which confers resistance to a bacterial pathogen. 相似文献
194.
LB Corbeil RP Gogolewski I Kacskovics KH Nielsen RR Corbeil JL Morrill R Greenwood JE Butler 《Canadian Metallurgical Quarterly》1997,61(3):207-213
AIMS/BACKGROUND: To characterise clinically a large kindred segregating retinitis pigmentosa and sensorineural hearing impairment in an autosomal dominant pattern and perform genetic linkage studies in this family. Extensive linkage analysis in this family had previously excluded the majority of loci shown to be involved in the aetiologies of RP, some other forms of inherited retinal degeneration, and inherited deafness. METHODS: Members of the family were subjected to detailed ophthalmic and audiological assessment. In addition, some family members underwent skeletal muscle biopsy, electromyography, and electrocardiography. Linkage analysis using anonymous microsatellite markers was performed on DNA samples from all living members of the pedigree. RESULTS: Patients in this kindred have a retinopathy typical of retinitis pigmentosa in addition to a hearing impairment. Those members of the pedigree examined demonstrated a subclinical myopathy, as evidence by abnormal skeletal muscle histology, electromyography, and electrocardiography. LOD scores of Zmax = 3.75 (theta = 0.10), Zmax = 3.41 (theta = 0.10), and Zmax = 3.25 (theta = 0.15) respectively were obtained with the markers D9S118, D9S121, and ASS, located on chromosome 9q34-qter, suggesting that the causative gene in this family may lie on the long arm (q) of chromosome 9. CONCLUSIONS: These data indicate that the gene responsible for the phenotype in this kindred is located on chromosome 9 q. These data, together with evidence that a murine deafness gene is located in a syntenic area of the mouse genome, should direct the research community to consider this area as a candidate region for retinopathy and/or deafness genes. 相似文献
195.
A. Witvrouw K. Maex W. De Ceuninck G. Lekens J. D'Haen L. De Schepper 《Microelectronics Reliability》1998,38(6-8)
The degradation due to stress induced voiding of nitride passivated Al-1 wt.% Si and Ti/TN/ Al-1wt.% Si-0.5 wt. % Cu/Ti/TN interconnects with widths ranging between 0.4 and 1.2 μm was studied by in-situ conventional
high resolution resistance measurements (HRRM) during storage at temperatures between 168 and 240°C. The conventional measurements on Al-Si lines, which lasted more than one year, clearly showed that the interconnect lifetime decreases with decreasing line width. With HRRM the degradation due to stress induced voiding can be detected much sooner and with much more detail. From the HRRM it is clear that the resistance changes during storage often happen in jumps and that the degradation has a rather complex alloy, line width and temperature dependence. Both for 0.4 and 0.6 μm wide Al---Si lines more degradation occurred for storage at 175 °C compared to storage at 200 °C. For the Al---Si---Cu stacks the degradation of 0.4 μm wide lines was worse for storage at 240°C compared to storage at 200 °C, but the opposite was true for the 0.6 μm wide lines. 相似文献
196.
Weikle R.M. II Kim M. Hacker J.B. De Lisio M.P. Popovic Z.B. Rutledge D.B. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1992,80(11):1800-1809
Although quasi-optical techniques are applicable to a large variety of solid-state devices, special attention is given to transistors, which are attractive because they can be used as either amplifiers or oscillators. Experimental results for MESFET bar-grid and planar grid oscillators are presented. A MESFET grid amplifier that receives only vertically polarized waves at the input and radiates horizontally polarized waves at the output is discussed. These planar grids can be scaled for operation at millimeter- and submillimeter-wave frequencies. By using modern IC fabrication technology, planar grid oscillators and amplifiers containing thousands of devices can be built, thereby realizing an efficient means for large-scale power combining 相似文献
197.
198.
Balasa F. Catthoor F. Hugo De Man 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》1995,3(2):157-172
Memory cost is responsible for a large amount of the chip and/or board area of customized video and image processing system realizations. In this paper, we present a novel technique-founded on data-flow analysis which allows one to address the problem of background memory size evaluation for a given nonprocedural algorithm specification, operating on multidimensional signals with affine indexes. Most of the target applications are characterized by a huge number of signals, so a new polyhedral data-flow model operating on groups of scalar signals is proposed. These groups are obtained by a novel analytical partitioning technique, allowing to select a desired granularity, depending on the application complexity. The method incorporates a way to tradeoff memory size with computational and controller complexity 相似文献
199.
Pb1–x
Ca
x
[(Co0.5W0.5)0·05Ti0.95]O3 ceramics with x = 0.24, 0.30 and 0.35, are prepared by a solid state reaction of oxides. Deviations from nominal chemical compositions and formation of segregated phases different from modified lead titanate perovskites, are studied. Pyro- and non-pyroelectric currents excited in the material by a thermal wave are investigated and related to mobility of electrical charges in the materials. 相似文献
200.
To make exploring a locale's heritage a challenging and compelling experience, the Venice Game uses a handheld platform and educational software that leverages video game techniques. 相似文献