There are multiple challenges in analysing pigments in historic watercolour paintings on paper, and typically noninvasive, in situ methods are required. Recent developments in portable analytical instrumentation have made this more accessible to heritage institutions, but many commercial systems are not optimised for the specific requirements of manuscripts and works on paper. This paper describes the successful use of Raman spectroscopy, X-ray fluorescence spectroscopy (XRF) and hyperspectral imaging to identify and map watercolour pigments used by the eighteenth century botanical illustrator, Ferdinand Bauer, and demystify the unusual colour code system found in his sketches. The value, delicate nature and large size of these paintings necessitated the use of using in situ, noncontact methods of analysis. A portable, bespoke Raman spectrometer specifically designed for analysing pigments from works on paper was used together with a bespoke portable Fibre optic reflectance spectrometer, portable X-Ray Fluorescence spectrometer and a hyperspectral imaging sensor. The results demonstrate that although there is a significant compromise between achieving good Raman spectroscopic results from artists' pigments and using sufficiently low laser power densities so as not to cause damage to the pigments, good results could be obtained with this portable system, particularly when combined with XRF, fibre optic reflectance spectroscopy (FORS) and hyperspectral imaging. Eight pigments were identified unequivocally from 125 watercolour paintings analysed, suggesting that Bauer used a more traditional and more limited palette than previously considered, and that his palette changed significantly in his later paintings. Similar pigments identified by the authors on colour chart that was discovered in 1999 in Madrid and attributed to Bauer, add weight to the attribution of this chart to Bauer. The data provides a much deeper insight into Bauer's colour annotations, and how he was able to achieve such an impressive degree of colour fidelity in his work.
This study compared the heart rate responses of two profoundly retarded, multiply handicapped children during the performance of closed-skill fine motor activities and open-skill gross motor activities. The fine motor skills were typical classroom activities, and the gross motor skills were a part of each child’s special physical education programming. Heart rates were recorded for 20-sec intervals from the onset of the performance of each skill until the task objective was obtained. Based upon the results of this study, we concluded that the closed-skill fine motor classroom activities induce physiological stress at levels never before suspected. It is suggested that the dramatic heart rate responses may result from a hyposensitive condition of the spindle afferents, the gamma efferents, and the kinesthetic joint receptors, or from a breakdown in the retrieval of the stored motor program resulting in inappropriate spatial and temporal summation. As a result of the heart rate responses, it is suggested that classroom learning programs may need to be redesigned to accommodate for fatigue in this type of child.
This study evaluated the effects of latency periods on the retention of gross motor skills in three profoundly retarded, multiply handicapped children, and the efficacy of a relearning model as a test of learning among these children. The study used a quasi-experimental, multiple baseline-across-subjects design. The subjects were taught a motor skill designed specifically to their abilities; the skill was retaught following latency periods of 90, 30, and 14 days during which time the skill was not practiced. Based upon the results of this study, it was concluded that the subjects had some ability to retrieve motor programs and that some feedback process operated to refine the motor program. It was determined that the number of trials required to achieve a criterion is dependent upon the latency interval, with a 14-day interval having no effect upon achievement of criterion. These findings are used to support an argument for intermittent programming for the retention of motor skills in profoundly retarded, multiply handicapped children, thereby helping them to maintain and expand their repertoire of behaviors.
The purpose of the study was to evaluate the effects of physical activities on the cardiovascular performances of three institutionalized, profoundly retarded, multiply handicapped children. Heart rates were recorded during the completion of selected motor activities using a combination of telemetered electrocardiograms (ECG) and standard wireless microphone/video technology. Each subject participated in the experiment for a minimum of 6 weeks. The relationships between mean heart rates and performance times for each subject were evaluated throughout the experiment. Based upon the data collected, it was concluded that gross motor activities may have a significant effect on the cardiorespiratory functioning of profoundly retarded, multiply handicapped children, provided the activities are performed for an extended period of time and on a regular basis. The activities selected for use in this study were developmentally based, and no special consideration was given to their aerobic demands on the subjects. The subjects’ level of functioning dictated the use of developmental criteria rather than other, more fitness oriented, criteria that are usually applied to nonhandicapped individuals.
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