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Accurate statics calculation and near-surface related noise removal require a detailed knowledge of the near-surface velocity field. Conventional seismic surveys currently are not designed to provide this information, and 3D high-resolution reflection/refraction acquisition is not feasible for large survey areas. Satellite images and vibrator plate attributes are dense low-cost data, which can be used in spatially extrapolating velocities from sparse uphole data by geostatistics. We tested this approach in two different areas of Saudi Arabia and found that the optimal recipe depends on the local geology. [ABSTRACT FROM AUTHOR]

Presents an abstract of the article "Differential Protection by UVB (290-320nm)-Absorbing Sunscreens From Responses to UV Radiation (UVR) in Hairless Mice," by V. E. Reeve, M. Bosnic, C. Boehm-Wilcox and R. D. Ley, published in the December 2, 1990 issue of the journal "Immunology & Cell Biology."

Background: There is evidence of a link between job stress and upper extremity work-related musculoskeletal disorders. However, the biobehavioral mechanisms by which psychosocial stress factors contribute to the development of musculoskeletal disorders are uncertain., Methods: Based on established principles of breathing and job stress and the relevant empirical literatures, a hyperventilation theory of job stress and work-related musculoskeletal disorders was developed., Results: Hyperventilation (overbreathing) refers to a drop in arterial CO2 caused by ventilation that exceeds metabolic demands for O2. Excessive loss of CO2 (increase in rate of flow of CO2 from cells to longs) that results from hyperventilation produces a rise in blood pH (i.e., respiratory alkalosis). This disruption in the acid-base equilibrium triggers a chain of systemic physiological reactions that have adverse implications for musculoskeletal health, including increased muscle tension, muscle spasm, amplified response to catecholamines, and muscle ischemia and hypoxia. Hyperventilation is often characterized by a shift from a diaphragmatic to a thoracic breathing pattern, which imposes biomechanical stress on the neck/shoulder region due to the ancillary recruitment of sternocelidomastoid, scalene, and trapezius muscles in support of thoraci breathing., Conclusions: A hyperventilation theory provides an innovative framework for understanding how job stress contributes to pathophysiological processes that increase the risk of work-related musculoskeletal disorders. With respect to the control of these disorders, a hyperventilation theory has important implications for establishing effective work organization interventions and individual stress-management methods. In this regard, breathing is a biobehavioral metric for assessing whether psychosocial aspects of work organization are in balance with a worker's needs and resources. A hyperventilation theory also provides a unique rationale for coping with job stress and musculoskeletal discomfort through breathing training, light physical exercise, and rest breaks.