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991.
Several creative domains, activities, and options are presented for psychological research, building on the suggestion that although many of these may seem remote from the usual interest of basic researchers, they are much less distant than commonly believed. Problems in the worlds of science, government, and the universities are discussed with relevance to their effects on the pursuit of creative research. The article concludes with some personal reminiscences that bear on the role of the scientist as a citizen and the dangers for science in today's political atmosphere. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Roache John D.; Stanley Melinda A.; Creson Daniel L.; Meisch Richard A.; Shah Nurun N. 《Canadian Metallurgical Quarterly》1996,4(3):308
The reinforcing effects of diazepam were examined in 4 female patients with generalized anxiety disorder but without histories of drug abuse. Under double-blind conditions, patients were given medication capsules containing either 4 mg diazepam or placebo that they could use "as needed" for anxiety. After a 1-week sampling period for each medication, participants repeatedly chose which medication they preferred over the next 4 weeks. Reinforcing effects of diazepam were demonstrated in 3 participants who showed exclusive diazepam preference. The results suggest procedures whereby drug self-medication behavior may be studied in an outpatient environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Stereotaxic Implantation of Electrodes in the Human Brain: A Method for Long-Term Study and Treatment 总被引：1，自引：0，他引：1
Heath Robert G. John Stanley B. Fontana Charles J. 《IEEE transactions on bio-medical engineering》1976,(4):296-304
A stereotaxic method for placement of electrodes in the human brain is described. Radiographic visualization of subcortical targets are discussed and error correction formulas are developed. Electrodes and fixation methods for long-term human implantation are described. Multiple stainless steel or silver bail electrodes have been implanted in 75 patients with schizophrenia, epilepsy, depression, Parkinson's disease, narcolepsy, and intractable pain. The silver ball electrode is more satisfactory for recording and stimulation. Biphasic 0.25-ms duration currents from 2-7 mA have been applied to animals and humans without evidence of structural damage. 相似文献
994.
In a variety of emerging networked computing system domains over the years, there have been bursts of activity on new medium access control (MAC) protocols, as new communication transceiver technologies with greater data‐movement performance or lower power dissipation have been introduced. To enable implementations flexible to evolving standards and improving application‐domain insight, such MAC protocols are typically initially implemented in software, and interface between applications or system software, typically executing on an embedded processor or microcontroller, and the evolving radio transceiver hardware. Many challenges exist in implementing MAC protocols across evolving or competing transceiver hardware implementations and processor architectures. Some of these challenges are peculiar to the requirements of MAC protocols, and others are a result of the plethora of system and processor architectures in the embedded systems domain. This article studies the challenges facing software implementations of MAC protocols running on embedded microcontrollers, and interfacing with radio transceiver hardware. Experience with an implementation of the IEEE 802.15.4 MAC across three hardware platforms with different processor, system, and systems software architectures is presented, focusing on implementation approach and interfaces. Pitfalls are pointed out, and guidelines are provided for ensuring that new MAC implementations are easily portable across processor architectures and transceiver hardware. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
995.
Stanley Gotshall Kathy Browder Jessica Sampson Terence Soule Richard Wells 《Genetic Programming and Evolvable Machines》2007,8(4):355-380
Simulations and modeling techniques are becoming increasingly important in understanding the behavior of biological systems. Detailed models help researchers answer questions in diverse areas such as the behavior of bacteria and viruses and aiding in the diagnosis and treatment of injuries and diseases. However, to yield meaningful biological behavior, biological simulations often include hundreds of parameters that correspond to biological components and characteristics. This paper demonstrates the effectiveness of genetic algorithms (GA) and particle swarm optimizer (PSO) based techniques in training biologically plausible behavior in a neuromuscular simulation of a biceps/triceps pair. The results are compared to human subjects during flexion/extension movements to show that these algorithms are effective in training biologically plausible behaviors on both neural and gross anatomical levels. Specific behaviors of interest that emerge include tonic tensions in both muscles during resting periods, biceps/triceps coactivation patterns, and recruitment-like behaviors. These are all fundamental characteristics of biological motor control and emerge without direct selection for these behaviors. This is the first time that all of these characteristic behaviors emerge in a model of this detail without direct selective pressure.
相似文献
| Richard WellsEmail: |
996.
ABSTRACT: Drying behavior at 60 °C was studied in uniform rings of apple fruit parenchyma after vacuum infiltration of fluids with different osmolality and surface tension. All infiltrations gave a halved final porosity. Both reduced surface tension and reduced osmolality caused tissue destruction shown as darker visual color. Addition of surfactant resulted in a higher drying rate on a surface area basis corresponding to 15% more water lost after 2 h. The results indicate that biological mechanisms related to function and structure of living tissue are important for drying behavior. The apple ring model is suitable for further studies of biological and other types of drying behavior in relation to the tissue organization. 相似文献
997.
998.
999.
Philip A. Ireland Stanley Z. Dziedzic Malcolm W. Kearsley 《Journal of the science of food and agriculture》1986,37(7):694-698
Quantitative high-performance liquid chromatography of the sapogenins was used to estimate the saponin content of soya beans (Glycine max (L.) Merr.) and commercially prepared soya flours, protein concentrate, protein isolate and soya milks. The level of saponin in whole soya beans as estimated (0.47%) was in agreement with other recent estimates. Saponins were also found in the various soya flours (0.43–0.67%), protein isolate (0.76%), soya milks (0.022–0.026%) but not in the protein concentrate. 相似文献
1000.
Luis G. Pedro Jaime A. da Silva Jos G. Barroso A. Cristina Figueiredo Stanley G. Deans Anja Looman Johannes J. C. Scheffer 《Flavour and Fragrance Journal》1999,14(5):287-289
The composition of the essential oils isolated from leaves and stems collected during the vegetative and the flowering phases of the plant, and from fruits of Chaerophyllum azoricum Trel., an endemic species of the Azores archipelago, was analysed by GC and GC–MS. Each of the three oils was dominated by its monoterpene fraction (82–91%), terpinolene (44–62%) and γ‐terpinene (9–31%) being the main oil components. The sesquiterpene fraction occurred in a concentration ranging from 3% to 8% with zingiberene as main component (1–5%). In addition to mono‐ and sesquiterpenes, the oils contained a significant amount of myristicin (5–9%). Copyright © 1999 John Wiley & Sons, Ltd. 相似文献