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1.
High-resolution positive and negative photoresists were used to fabricate ?/4-phase-shifted corrugations by holographic exposure. To avoid mixing these photoresists, cyclised polyisoprene was used as a midlayer. The shape and depth of the corrugations on the positive and negative photoresist regions were almost the same. Single-mode operation at the Bragg wavelength was confirmed in lasers with the corrugation. 相似文献
2.
The atomistic structure and energies of high-index interphase boundaries are explored using a combination of molecular statics
and dynamics simulations with embedded atom potentials. We investigate planar boundaries between the α2 and γ phases in the Ti−Al system. The class of boundaries considered has a high-index boundary orientation; the orientation
relationship between the α2 and γ phases also is high index, and a set of planes from each phase meet edge to edge at the boundary plane. For the particular
case of a boundary that is commensurate in one direction and coincides with a moiré plane given by the so-called “Δg” diffraction condition, the boundary is not structurally singular, but it is energetically stable and does not appear to
dissociate into other low-energy configurations. Misfit compensating defects are not observed; misfit in directions other
than the commensurate one appears to be distributed uniformly. The boundary energy is evaluated as a function of the orientation
of the boundary plane, and the edge-to-edge (moiré) boundary is found to lie in an energy cusp.
This article is based on a presentation made in the “Hume-Rothery Symposium on Structure and Diffusional Growth Mechanisms
of Irrational Interphase Boundaries,” which occurred during the TMS Winter meeting, March 15–17, 2004, in Charlotte, NC, under
the auspices of the TMS Alloy Phases Committee and the co-sponsorship of the TMS-ASM Phase Transformations Committee. 相似文献
3.
The goal of the PMS project is to produce an environment in which the intelligent online assessment of the design for large-scale ADA programming projects is provided. The focus is on the representation of knowledge about the design process for an individual module. Changes in pseudocode complexity are measured in terms of partial metrics. These metrics can take the designers inferences about the pseudocode program structure into account when assessing module complexity. Next, a model of the stepwise refinement process is given which demonstrates how pseudocode elaboration decisions can be modelled in partial metric terms. Finally, the decisions associated with each refinement step for 17 example refinements taken from the computer science literature are described using partial metrics. 相似文献
4.
M Fornerod J van Deursen S van Baal A Reynolds D Davis KG Murti J Fransen G Grosveld 《Canadian Metallurgical Quarterly》1997,16(4):807-816
The oncogenic nucleoporin CAN/Nup214 is essential in vertebrate cells. Its depletion results in defective nuclear protein import, inhibition of messenger RNA export and cell cycle arrest. We recently found that CAN associates with proteins of 88 and 112 kDa, which we have now cloned and characterized. The 88 kDa protein is a novel nuclear pore complex (NPC) component, which we have named Nup88. Depletion of CAN from the NPC results in concomitant loss of Nup88, indicating that the localization of Nup88 to the NPC is dependent on CAN binding. The 112 kDa protein is the human homologue of yeast CRM1, a protein known to be required for maintenance of correct chromosome structure. This human CRM1 (hCRM1) localized to the NPC as well as to the nucleoplasm. Nuclear overexpression of the FG-repeat region of CAN, containing its hCRM1-interaction domain, resulted in depletion of hCRM1 from the NPC. In CAN-/- mouse embryos lacking CAN, hCRM1 remained in the nuclear envelope, suggesting that this protein can also bind to other repeat-containing nucleoporins. Lastly, hCRM1 shares a domain of significant homology with importin-beta, a cytoplasmic transport factor that interacts with nucleoporin repeat regions. We propose that hCRM1 is a soluble nuclear transport factor that interacts with the NPC. 相似文献
5.
6.
G Arepally C Reynolds A Tomaski J Amiral A Jawad M Poncz DB Cines 《Canadian Metallurgical Quarterly》1995,104(6):648-654
The diagnosis of heparin-induced thrombocytopenia (HIT) may be affirmed by demonstrating heparin-dependent anti-platelet antibodies using the 14C-serotonin release assay (SRA). In this study, results of the SRA was compared with the recently described platelet factor 4 (PF4)/heparin enzyme-linked immunosorbent assay (ELISA). Compared with the SRA, the sensitivity and specificity of a PF4/heparin ELISA was 87% and 92%, respectively, using an assay developed in our laboratory; and 90% and 98%, respectively, using a commercially developed kit (Diagnostica Stago, Asnieres, France). However, antibodies to PF4/heparin were also detected in up to 8% of patients whose plasma was negative by SRA, and 23% of patients receiving heparin who were not thrombocytopenic. These data indicate that results obtained with the PF4/heparin ELISA and the SRA are generally in accord in patients with a clinical diagnosis of HIT. However, discrepant results occur in approximately 20% of cases because of the greater sensitivity of ELISA and the possible involvement of other heparin-binding proteins. The fact that each assay contributes independent information in some cases must be considered in the sequence of test performance and in providing consultation to the practicing hematologist. 相似文献
7.
8.
We consider the problem of turbo multiuser detection for synchronous and asynchronous code-division multiple-access (CDMA) in the presence of unknown users. Turbo multiuser detectors, as previously developed, typically require knowledge of the signature waveforms of all of the users in the system and ignore users whose signature sequences are unknown, e.g., users outside the cell. We develop turbo multiuser detection for CDMA uplink systems and other environments in which the receiver has knowledge of the signature waveforms of only K˘⩽ K users. Subspace techniques are used to estimate the interference from the unknown-users and the interference estimate is subtracted from the received signal. We see that the new receiver significantly outperforms the conventional turbo multiuser receiver for moderate and high signal-to-noise ratios. It is also seen that the traditional turbo receiver provides little gain through iteration when unknown users are present 相似文献
9.
T Reynolds 《Canadian Metallurgical Quarterly》1993,85(17):1366-1368
10.
SD Walter SE Birnie LD Marrett SM Taylor D Reynolds J Davies JJ Drake M Hayes 《Canadian Metallurgical Quarterly》1994,84(3):367-376
OBJECTIVES: Our objectives were (1) to describe an analysis of the spatial pattern of cancer incidence in Ontario and (2) to discuss the quality of data in the Ontario Cancer Registry with respect to the accuracy of local cancer rates. METHODS: Cancer incidence rates were calculated for 22 cancer sites in 49 counties of Ontario during 1976 to 1986. Capture-recapture methods were used to estimate completeness of case registration, and completeness of residence information was also assessed. Spatial autocorrelation was used in measuring the geographic pattern of incidence rates. Comparisons were also made between sexes and with earlier data from 1966 to 1975. RESULTS: The quality of the geographic data in the registry appeared good, and corrections for incomplete or inaccurate registration had little impact. About one third of the sex-site combinations showed some evidence of spatial patterning in the cancer rate. Particularly strong regional variation was noted for cancers of the stomach, lung, uterus, and prostate. CONCLUSIONS: The analysis revealed a number of cancers with significant spatial patterning of risk. Further work is needed to relate the cancer data to other information on potential life-style and environmental factors. 相似文献