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111.
Szymusiak Ronald; McGinty Dennis; Shouse Margaret N.; Shepard Diane; Sterman Maurice B. 《Canadian Metallurgical Quarterly》1990,104(1):217
Sensorimotor electroencephalogram (EEG) frequencies in cats were evaluated with power spectral analysis before and after 3 doses of atropine sulfate. All doses of atropine tested caused enhanced EEG slow waves (0–7 Hz) and spindles (8–25 Hz) during waking immobility, and postdrug frequency profiles during slow-wave sleep and waking immobility were identical. With 0.75 mg/kg atropine, movement (head movement, locomotion) resulted in EEG desynchronization and reduced power in all frequencies less than 24 Hz. After 1.5 or 3.0 mg/kg atropine, power in low frequencies remained elevated during movement, but power in spindle frequencies was significantly reduced compared with other states. During active REM sleep after 1.5 mg/kg atropine, power in spindle frequencies was significantly lower than that during quiet REM sleep. These results indicate that the sensorimotor cortical EEG in cats is under the control of multiple systems. At least 1 of these systems is active during movement, and its actions are resistant to muscarinic receptor blockade. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
112.
113.
Theobald CE Mosha Maurice R Bennink 《Journal of the science of food and agriculture》2005,85(9):1513-1522
This study was conducted to evaluate protein quality, acceptability and storage stability of processed cereal–bean–sardine composite foods for pre‐school age children in Tanzania. Four composite products namely corn–bean–sardine meal (CBSM), bean meal (BM), sorghum–bean–sardine meal (SBSM) and rice–bean–sardine meal (RBSM) were formulated to maximize the amino acid score for pre‐school age children and were processed by extrusion, drum‐processing and conventional cooking. The products were evaluated for true protein digestibility (TPD) and protein digestibility‐corrected amino acid score (PDCAAS). The TPD and PDCAAS were highest in the extruded products. The TPD values for the products ranged from 82 to 93%. The PDCAAS values for the composite foods were 64–86% and were greater than the minimum value of 60% recommended by FAO/WHO/UNU. There were no significant (p > 0.05) variations in the amino acid contents for foods processed by extrusion, drum‐processing or conventional cooking. Threonine was most limiting in the CBSM, SBSM and RBSM while methionine + cysteine were most limiting in the BM. Sensory evaluation showed that, relative to the traditional cornmeal—Uji, the extruded CBSM and SBSM had significantly superior (p ≤ 0.05) texture and highly acceptable color and taste. Storage of the products up to 16 weeks at 38 °C resulted in a small but significant increase (p ≤ 0.05) in the malondialdehyde concentrations; nevertheless, the levels remained within the acceptable range found in processed commercial supplements. Total acids, pH and organoleptic attributes did not change significantly (p > 0.05) during storage and the foods were acceptable to the end of the storage period. Copyright © 2005 Society of Chemical Industry 相似文献
114.
Maurice H. ter Beek Gabriele Lenzini Marinella Petrocchi 《Electronic Notes in Theoretical Computer Science》2005,128(5):105
In [Kleijn, J., Team Automata for CSCW – A Survey –, Petri Net Technology for Communication-Based Systems—Advances in Petri Nets, LNCS 2472, Springer, 2003, 295–320], Kleijn presented a survey of the use of team automata for the specification and analysis of phenomena from the field of computer supported cooperative work, in particular notions related to groupware systems. In this paper we present a survey of the use of team automata for the specification and analysis of some issues from the field of security. In particular, we show how team automata can adequately be used to model and verify various access control policies, multicast/broadcast communication protocols, and general (cryptographic) communication protocols. 相似文献
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116.
Synchronizations in Team Automata for Groupware Systems 总被引:7,自引:0,他引:7
Maurice H. ter Beek Clarence A. Ellis Jetty Kleijn Grzegorz Rozenberg 《Computer Supported Cooperative Work (CSCW)》2003,12(1):21-69
Team automata have been proposed in Ellis (1997) as a formal framework for modeling both the conceptual and the architectural level of groupware systems. Here we define team automata in a mathematically precise way in terms of component automata which synchronizeon certain executions of actions.At the conceptual level, our model serves as a formal framework in whichbasic groupware notions can be rigorously defined and studied.At the architectural level, team automata can be used as building blocksin the design of groupware systems. 相似文献
117.
Peter F. Martin W. Allan Gillespie Maurice G. Kelliher 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,240(2):445-451
A versatile electron spectrum monitor has been developed for the UK free electron laser project. The monitor uses secondary emission from 96 tungsten foils and microprocessor-controlled sampling electronics to produce a high-resolution electron energy spectrum. A 30-channel prototype is currently operating as a beam profile monitor and has been extensively used in emittance measurements at the Kelvin Laboratory linac. 相似文献
118.
The physics of mechanical alloying: A first report 总被引:14,自引:0,他引:14
In this paper, we present a first attempt to define the basic geometry, mechanics, and physics of the process of mechanical
alloying. The geometry of the collision events which lead to particle fragmentation and coalescence is modeled on the basis
of Hertzian contacts between the grinding media which entrap a certain amount of material volume between the impacting surfaces.
This geometry essentially defines the volume of material affected per collision, and from this information and characteristics
of the specific mill and the material being processed, impact times, powder strain rates and strains, powder temperature increase,
powder cooling times, and milling times can be approximated. 相似文献
119.
The deformation and fragmentation behaviour in a toughened ceria-stabilized zirconia ceramic have been investigated by using unlubricated repeated metallic point contact loading at room temperature to explore the possibilities of cyclic fatigue effects. All tests were conducted on a purpose-designed and built computer-controlled apparatus. 120° hardened silver steel cones were cyclically loaded on the polished Ce-TZP substrate, and the damage was observed and analysed as a function of the number of cycles for loads of 19.6 ± 9.8 N. The ground tips of the cones plastically deformed during the initial loading cycle to produce a flattened end which conformed with the substrate. A tetragonal → monoclinic martensitic transformation occurred in the zirconia beneath, and adjacent to, the contact zone. This transformation zone increased in size as the number of cycles increased, even though there was virtually no change in the diameter of the flattened tip. The expansion associated with this phase change in the zirconia caused granular lifting from the surface, at the edge of the contact zone, that resulted in intergranular fragmentation and spelling of the substrate. The hardness of the substrate in the contact zone increased by approximately 15% after 2×105 cycles. Traces of metal transfer onto the ceramic substrate could be observed only at 2×105 cycles and above. 相似文献
120.