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41.
Several samples of geological stones from statuary pedestals found in various archaeological sites in Cyprus have been characterized using non-contact laser infrared photothermal radiometry. Thermal diffusivities and effective optical absorption coefficients were calculated using a one-dimensional thermal-wave model. The mean values and standard deviations were tabulated and comparisons were made with lithographic and petrographic studies of the samples. Good correlations were found, thus demonstrating that laser photothermal archaeometry is a promising methodology for the accurate, potentially non-destructive and convenient characterization of the origins of ancient stones in Cyprus and other geological and archaeological sites. 相似文献
42.
The localization or representation of mental abilities in the brain have always been considered as key questions for understanding the organization of the human nervous system. Particularly with the advent of modern electrophysiological and imaging techniques that provide maps of electromagnetic fields and metabolic processes on the living central nervous system, the representation theory is experiencing a scientific renaissance in neurology, but is only one theory, however, in the succession of a long philosophical tradition dealing with the possible identification of mental phenomena and brain processes. This dichotomy was formulated at the latest in the Cartesian dualism of res cogitans and res extensa of the mind-body problem. Nowadays philosophical discussion, on the contrary, is dominated by monistic concepts that attempt to explain the mental realm on an organic foundation in order not to succumb to the problem of a psychophysical dualism. Of these, the identity theory offers a philosophically plausible concept postulating that the identity of brain conditions and mental phenomena is based on organic foundations. In this theory, the efforts of brain research converge on the representations of mental phenomena in the human nervous system. In a comprehensive approach, both concepts could complement each other. 相似文献
43.
Random Time Sampling is an innovative data collection method which has potential for adaptation and use by geographers. Individual pocket-sized programmable beepers were used in a pilot study of the uses of time by older households and older people's attitudes to different activities. Random beeps were used to prompt individuals living in eleven Melbourne suburbs to record time use data in diaries over a period of a week. The method proved extremely effective and reliable, and many participants reporting that they enjoyed the exercise. 相似文献
44.
Morphological Impacts and Implications of a Trial Release on the Wingecarribee River,New South Wales
A trial, monitored release on the Wingecarribee River over 27 days had a peak discharge below the Wingecarribee Dam of 1090 ML/d, which had a flow duration of 0.95 per cent. Morphological impacts on 29 km of channel below the dam included bank erosion, concentrated neck overflow, bed degradation and channel widening at recent cutoffs, sedimentation in weir pools and overbank flow, particularly at discharges greater than 800 ML/d. Prolonged operational releases at bankfull discharge (400–800 ML/d) will have the greatest morphologic impacts and should be avoided. Pulses which dissipate stream power over a broad, well-vegetated floodplain should be incorporated in the operational release policy, provided such pulses are phased to facilitate channel and vegetation recovery. 相似文献
45.
I summarize recent archaeological work in Oaxaca, Mexico, with a focus on questions central to world prehistory: the origin and collapse of complex societies. Monte Albán was the capital of an emerging civilization in the southern highlands of Mexico during the second half of the first millennium B.C. Soon after the foundation of the ancient city, there is evidence for state formation and a political expansion into regions outside the Valley of Oaxaca. Centuries later, Monte Albán went into decline, giving way to the competing small polities found throughout Oaxaca at the time of the Spanish conquest. Since the late 1960s, our knowledge of these changes has been transformed by study of Oaxaca's pre–Monte Albán past, regional settlement surveys, and processual model building. Evolutionary and historical perspectives allow for significant refinement of current debates surrounding the rise and fall of complex societies in Oaxaca. 相似文献
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York GK 《Journal of the history of the neurosciences》1996,5(1):34-42
Charles Edouard Brown-Séquard used observation of recovered patients and experimental animals to support his theory of cerebral localization. Recovery theories assume that the nervous system is composed of one organ or many, and that each organ has one function or many. From his own studies as well as others, Brown-Séquard concluded that the brain contained at least nine separate organs, each with a single distinct function, and that each organ is organized, not as a geographically isolated cluster of neurons, but as a widely disseminated network. According to his view, function is not uniformly distributed in an organ. Focal necrosis of part of an organ temporarily inhibits the action of distant, undamaged parts; resolution of this inhibition results in recovery. Using this theory of cerebral localization and recovery, Brown-Séquard practiced an early form of scientific neurology. 相似文献