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41.
SG Kshirsagar 《Canadian Metallurgical Quarterly》1976,106(10):1475-1483
The effect of feeding stable strontium (Sr) on the tissue alkaline and acid phosphatase activities was studied in young rats. These activities were reduced in liver and small intestine by 10% to 15% at 2 weeks, 20% to 30% at 4 weeks and in kidney by 20% at 6 weeks only in rats fed 2% Sr diet; bone alkaliine phosphatase activity was, however, increased by 80% to 100% (2-6 weeks) in these rats. Gross lesions like paralysis, hemorrhage, rickets and high mortality were observed after 4 to 6 weeks. Although no such lesions were seen, appreciable changes in enzyme activities as mentioned above were discernible in rats fed 1% Sr diet for 6 weeks. Feeding of a 0.5% Sr diet for a period up to 6 weeks had no deleterious effect. Recovery following consumption of a normal diet for 2 weeks was almost complete in liver and small intestine but not in kidney. The elevated tissue Sr levels do not explain the pronounced losses seen in this investigation as compared to those in the earlier in vitro experiments. This study depicts the possible damage due to prolonged therapeutic use of large amounts of stable Sr for the removal of radiostrontium. 相似文献
42.
Luisa Quintino Gervasio Pimenta Danut Iordachescu R. M. Miranda N. V. P pe 《Materials and Manufacturing Processes》2006,21(1):63-73
MIG welding of zinc-coated thin plates in the automotive industry leads to major issues, mainly zinc evaporation followed by a decrease of corrosion resistance, as well as residual strains and stresses difficult to minimize. The use of a lower heat input technique for joining galvanized steels would bring significant benefit, if the final overall mechanical properties of the joints are adequate for the application. The use of MIG brazing (MIGB) with the recently commercialized alloyed copper-based filler metal is an alternative worth considering. The present paper addresses the MIGB processes, describing the influence of the different shielding gases and the process parameters on the mechanical, corrosion, and metallurgical properties of the joint, when lower heat input procedures are targeted. The paper describes the influence of the gases on the mechanical properties of the brazed joint, both in normal conditions after joining and after corrosion in a salt water environment. Microstructural features of the different zones are discussed. Results of corrosion and tensile tests are presented and interpreted. 相似文献
43.
Nicola Capuano Angelo Gaeta Giuseppe Guarino Sergio Miranda Stefania Tomasiello 《Behaviour & Information Technology》2016,35(11):968-979
ABSTRACTIn this paper, we present our results related to the definition of a methodology that combines augmented reality (AR) with semantic techniques for the creation of digital stories associated with museum exhibitions. In contrast to traditional AR approaches, we augment real-world elements by supplementing contents of a museum exhibition with additional inputs that provide new and different meanings. In this way we augment a cultural resource with respect to both its presentation and meaning. The methodology is framed in the cultural re-mediation theory and is grounded on a set of ontologies aimed at modelling a cultural resource and correlating it with external multimedia objects and resources. To provide an easy tool for the creation of museum narratives, the methodology makes use of a set of recognised practices widely adopted by museum curators that have been formalised through inference rules. The defined methodology has been experimented in a scenario related to Flemish paintings to validate the augmentation of cultural objects with two different approaches, the first basing on similarities and the second on dissimilarities. 相似文献
44.
Diederik Verkest Julio Leao Da Silva Jr. Chantal Ykman Kris Croes Miguel Miranda Sven Wuytack Francky Catthoor Gjalt De Jong Hugo De Man 《The Journal of VLSI Signal Processing》1999,21(3):185-194
MATISSE is a design environment intended for developing systems characterized by a tight interaction between control and data-flow behavior, intensive data storage and transfer, and stringent real-time requirements. Matisse bridges the gap from a system specification, using a concurrent object-oriented language, to an optimized embedded single-chip hardware/software implementation. Matisse supports stepwise exploration and refinement of dynamic memory management, memory architecture exploration, and gradual incorporation of timing constraints before going to traditional tools for hardware synthesis, software compilation, and inter-processor communication synthesis. With this approach, specifications of embedded systems can be written in a high-level programming language using data abstraction. Application of MATISSE on telecom protocol processing systems in the ATM area shows significant improvements in area usage and power consumption. 相似文献
45.
46.
Raimundo Almeida-Filho Fernando P. Miranda Tadashi Yamakawa 《International journal of remote sensing》2013,34(13):2683-2688
Mapping of a tonal anomaly in an area of hydrocarbon microseepage was possible using a Landsat-Thematic Mapper false-colour composite consisting of TM2/3, TM4/3 and of the difference TM2/3-TM4/3, displayed as red, green and blue, respectively. In this false-colour composite, green and yellow express variations in the vegetation cover, whereas hues of magenta are related to terrain conditions representing bleached materials, which occur close to the centre of a soil gas anomaly. Simultaneous occurrence of anomalous soil gas values with magnetic and radioactive minerals suggests that a reducing environment associated with the microseepage phenomenon created the bleached materials, identified as a tonal anomaly in the enhanced TM image. 相似文献
47.
Abstract Musicians have long been interested in using iterative processes to aid the composition of musical forms (macrostructure) and to synthesize sounds (microstructure). This paper introduces a new sound synthesis method exploring the non-linear behaviour of two iterative cross-coupled digital oscillators. It begins with a brief introduction to iterative systems followed by background information on previous attempts at using them for synthesizing sounds (e.g. feedback frequency and amplitude modulations). Next, it introduces our synthesis method and briefly explains how it has been implemented in a system for real-time composition and performance. The paper concludes with a discussion on how the system has been put into practice to compose and perform a number of works. 相似文献
48.
The present work focuses on a posteriori, equilibrium based, reconstruction of transverse stress profiles in the finite element analysis of FSDT laminated plates. The accuracy of this reconstruction depends on accuracy of the first and second-order derivatives of the plate stress resultants, which is not guaranteed by most available low-order plate finite elements. To cure this trouble, two different strategies, based on the Recovery by Compatibility in Patches procedure, are here proposed and compared. Numerical results of typical reconstructed transverse stress profiles are presented showing the effectiveness of the proposed approach. 相似文献
49.
Ray Lara A.; Miranda Robert Jr.; MacKillop James; McGeary John; Tidey Jennifer W.; Rohsenow Damaris J.; Gwaltney Chad; Swift Robert W.; Monti Peter M. 《Canadian Metallurgical Quarterly》2009,17(2):122
Topiramate, an anticonvulsant medication, is an efficacious treatment for alcohol dependence. To date, little is known about genetic moderators of side effects from topiramate. The objective of this study was to examine 3 single nucleotide polymorphisms (SNPs) of the glutamate receptor GluR5 gene (GRIK1) as predictors of topiramate-induced side effects in the context of a laboratory study of topiramate. Heavy drinkers (n = 51, 19 women and 32 men), 75% of whom met criteria for an alcohol use disorder, completed a 5-week dose escalation schedule to a target dose of either 200 or 300 mg or matched placebo. The combined medication groups were compared with placebo-treated individuals for side effects at target dose. Analyses revealed that an SNP in intron 9 of the GRIK1 gene (rs2832407) was associated with the severity of topiramate-induced side effects and with serum levels of topiramate. Genes underlying glutamatergic neurotransmission, such as the GRIK1 gene, may help predict heterogeneity in topiramate-induced side effects. Future studies in larger samples are needed to more fully establish these preliminary findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Merino Gonzalez J.L. Ortiz Saenz F. Valencia Miranda G. 《Solid-State Circuits, IEEE Journal of》1991,26(9):1270-1277
The shumbler (shuffler/scrambler) is a circuit designed and fabricated to form part of a broadband customer premises network. The circuit is implemented in 1.2-μm BiCMOS double-metal technology. The circuit is bidirectional, and can perform the functions of scrambling and shuffling or descrambling and unshuffling by means of control signals to three integrated multiplexers. The shumbler also includes a programmable multiplexer that allows the selection of one out of the 16 output channels of the shuffler through a serial output for local system test purposes. The shumbler circuit interfaces emitter-coupled-logic (ECL) and transistor-transistor-logic (TTL) logic levels using a single power supply of -5 V, dissipating 1.5 W, and encapsulated in a 68-pin LCC package with a flat heat spreader which ensures a thermal resistivity of about 10°C/W 相似文献