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101.
The most common group of squirrel monkey vocalizations, peeps, are emitted during different social situations including social separation, affiliative interactions, feeding and aggressive confrontations. The present experiments investigated whether peeps and other vocalizations emitted during different social contexts are pharmacologically altered in a similar manner. First, vocalizations were characterized during (1) social separation in juveniles, and (2) "resident-intruder" aggressive confrontations between dominant monkeys from different social groups. Then, the effects of alcohol (EtOH) and the benzodiazepine chlordiazepoxide (CDP) on vocalizations during social separation and during aggression were examined. Isolated juveniles emitted only one type of call, the isolation peep. Resident monkeys primarily emitted peeps, but also emitted cackles, chucks, noisy calls and pulsed calls. Aggressive peeps were similar in structure and frequency (kHz) to isolation peeps, but were shorter in duration. At the same doses, both CDP (0.3-3 mg/kg) and EtOH (0.1-1.0 g/kg) reduced explosive motor behaviors and isolation peeps in juvenile monkeys during social separation and increased threat displays and aggression peeps in resident monkeys during confrontations with an intruder monkey from a different social group. Thus, similarly structured vocalizations that were emitted during social separation and aggression were very sensitive to EtOH and CDP, but the social context determined the direction and magnitude of effects. 相似文献
102.
This paper concerns a Human Reliability Assessment (HRA) carried out over a period of two years as part of a Nuclear Power Plant Probabilistic Safety Assessment (PSA). The HRA involved all elements of the HRA process, from problem definition and task analysis, through error representation and quantification, to impact assessment, error reduction, quality assurance and documentation. The aim of this paper is to show the methodology of HRA as applied in a real PSA, highlighting various elements of the HRA, and how the HRA interfaced with the PSA. Comments are also given on practical aspects and impacts of the various approaches, and the usefulness of a hybrid HRA/PSA team approach. 相似文献
103.
104.
Stephen M. Walls John V. Kucsera Joshua D. Walker Taylor W. Acee Nate K. McVaugh Daniel H. Robinson 《Computers & Education》2010
Instructors in higher education are disseminating instructional content via podcasting, as many rally behind the technology’s potential benefits. Others have expressed concern about the risks of deleterious effects that might accompany the adoption of podcasting, such as lower class attendance. Yet, relatively few studies have investigated students’ perceptions of podcasting for educational purposes, especially in relation to different podcasting forms: repetitive and supplemental. The present study explored students’ readiness and attitudes towards these two forms of podcasting to provide fundamental information for future researchers and educators. The results indicated that students may not be as ready or eager to use podcasting for repetitive or supplemental educational purposes as much as we think they are, but they could be persuaded. 相似文献
105.
Ian Scott Evans Jessica Miki Jessee Ho Derek T. Robinson 《International journal of remote sensing》2016,37(6):1411-1430
Topographic and elevation data are essential in the development of supporting infrastructure around mining sites. The de facto standard for acquiring elevation data is through light detection and ranging (lidar). The high labour and monetary cost of acquiring lidar has fostered more cost-effective approaches for creating elevation models that use stereo photogrammetry. To assess the accuracy of stereo-photogrammetry-derived elevation models and their potential application, we benchmark satellite (Worldview-2) and aircraft (South Central Ontario Orthoimagery Project; SCOOP) stereo-derived digital surface models (DSMs) against a lidar-derived DSM. Our results show that both stereo-derived DSMs have strong monotonic correlations with lidar across a range of land-cover types and slopes. The overall vertical accuracy of Worldview-2 and SCOOP DSMs are similar and do not meet the United States National Digital Elevation Program (NDEP) standards. However, accuracy assessment across land-cover types and slope categories show that specific land cover types (i.e. grass, row crops/pasture, sparse vegetation and marsh) on gently sloping terrain compare well to lidar data and meet NDEP accuracy standards. We situate the presented research in the context of northern resource development and discuss opportunities to improve the vertical accuracy of stereo-derived DSMs, for example, through unmanned aerial systems. 相似文献
106.
107.
Kobeissy FH Sadasivan S Oli MW Robinson G Larner SF Zhang Z Hayes RL Wang KK 《Proteomics. Clinical applications》2008,2(10-11):1467-1483
The rapidly growing field of neuroproteomics has expanded to track global proteomic changes underlying various neurological conditions such as traumatic brain injury (TBI), stroke, and Alzheimer's disease. TBI remains a major health problem with approximately 2?million incidents occurring annually in the United States, yet no affective treatment is available despite several clinical trials. The absence of brain injury diagnostic biomarkers was identified as a significant road-block to therapeutic development for brain injury. Recently, the field of neuroproteomics has undertaken major advances in the area of neurotrauma research, where several candidate markers have been identified and are being evaluated for their efficacy as biological biomarkers in the field of TBI. One scope of this review is to evaluate the current status of TBI biomarker discovery using neuroproteomics techniques, and at what stage we are at in their clinical validation. In addition, we will discuss the need for strengthening the role of systems biology and its application to the field of neuroproteomics due to its integral role in establishing a comprehensive understanding of specific brain disorder and brain function in general. Finally, to achieve true clinical input of these neuroproteomic findings, these putative biomarkers should be validated using preclinical and clinical samples and linked to clinical diagnostic assays including ELISA or other high-throughput assays. 相似文献
108.
Gaucher's disease is a lysosomal storage disease in which cells of the reticuloendothelial system accumulate the lipid glucocerebroside. It is characterized by slowly progressive visceral and osseous involvement. One of the latter manifestations includes lipid infiltration of bone marrow. We monitored the rate of inhaled 133Xe uptake and wash-out over diseased and normal metaphyseal and epiphyseal areas of the knee. Twenty-two patients (15 adults, 7 children) with various degrees of previously diagnosed Gaucher's disease were positioned supine under a gamma-camera interfaced to a computer system. All patients rebreathed 133Xe gas from a closed system for 10 min followed by 14 min of wash-out. Digitized images of the lung, liver, spleen, bony sites and soft tissue were obtained at 1 min intervals during the wash-in and wash-out phases. Counts for each ROI were normalized per 100 pixels and plotted as a function (time). Maximum uptake was also calculated by relating the counts/ROI/100 pixels to the 10 min integrated lung count during equilibrium (the administered "dose"). There was essentially no 133Xe uptake in liver and spleen involved with Gaucher's disease. Monophasic uptake and biphasic wash-out curves were observed in the limited investigative population. Skeletal Gaucher deposits released the 133Xe at a greater rate relative to soft tissue. 相似文献
109.
Robinson HC Hahn Y 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1991,38(3):305-310
The electrical reflection coefficient r(e) and velocity shift (Deltanu/nu)(e) for grooves has never been formulated. All previous calculations for r(e) and (Deltanu/nu)(e) have used formulas valid for the reflection of a surface acoustic wave (SAW) from an array of conducting strips. However, the discontinuity in electrical boundary conditions leading to these formulas does not exist in groove gratings. A new expression for the electrical reflection coefficient and velocity shift for some material overlays is derived from both the variational principle and perturbation theory. The results for various substrates are compared to show the agreement between the two approaches. The implications of this new formulation for the design of grooved arrays on various materials are discussed, effectively resolving the discrepancy between theory and experiment. 相似文献
110.
The concept of cardiac reconditioning centers for the prevention and rehabilitation of coronary patients has been tremendously successful in Germany over the past 20 years. At least 40 such centers are located throughout the country. Physicians, nurses, and physical therapists work closely together in the various facets of the rehabilitation process. The financial backing for these facilities is primarily through governmental and regional insurance companies, whose officials are apparently convinced that in the long run supporting preventive measures is financially sound. Objective data supporting their convictions come from studies such as that of Brusis, who showed that such as that of 1,500 employees was diminished by nearly 70 percent during a two-year period after cardiac reconditioning, as compared to a similar time period before the rehabilitation experience. Subjective benefits, which are extremely difficult to quantitate in meaningful terms, were nonetheless expressed by nearly all the patients with whom I conversed. Perhaps they have experienced the same feelings that Mark Twain did when he observed that "all frets and worries and chafings sank to sleep in the presence of the benignant serenity of the Alps; the Great Spirit of the Mountains breathed his own peace upon their hurt minds and sore hearts and healed them." 相似文献