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Convection as one dominant source of atmospheric gravity waves (GWs) has been in focus of investigation over recent years. However, its spatial and temporal forcing scales are not well known. In this work we address this open issue by a systematic verification of free parameters of the Yonsei convective GW source scheme based on observations from the High Resolution Dynamics Limb Sounder (HIRDLS). Observational constraints are taken into account by applying a comprehensive observational filter on the simulated GWs. By this approach, only long horizontal scale convective GWs are addressed. Results show that effects of long horizontal scale convective GWs can be successfully simulated by the superposition of three or four combinations of parameter sets reproducing the observed GW spectrum. These selected parameter sets are different for northern and southern summer. Although long horizontal scale waves are only part of the full spectrum of convective GWs, the momentum flux of these waves are found to be significant and relevant for the driving of the QBO. The zonal momentum balance is considered in vertical cross sections of GW momentum flux (GWMF) and GW drag (GWD). Global maps of the horizontal distribution of GWMF are considered and consistency between simulated results and HIRDLS observations is found. The latitude dependence of the zonal phase speed spectrum of GWMF and its change with altitude is discussed. [ABSTRACT FROM AUTHOR]

Patients with chronic disabling low-back pain have poor prospects of returning to work. The authors tested a treatment program of functional restoration with behavioral support through 1 year prospective observation of patients disabled for an average of 19 months without evidence of surgically correctable disease. Ninety patients were studied: 59 program graduates, five program dropouts, 17 patients denied program authorization by their insurance carriers, and six crossover patients. Three patients were admitted but refused to participate in the treatment program. Initial demographic, physical, and self-assessment attributes were similar for all four groups. At year's end, 81% of program graduates, 40% of the dropouts, and 29% of those denied the program had returned to work. All six crossover patients were working 6 months after treatment. Program graduates showed significant improvements in self-assessed pain, disability, and depression, and in physical capacities after 3 weeks of treatment. These improvements were maintained through the year except for partial decreases in frequent lifting, cycling endurance, and isokinetic trunk extension strength. Functional restoration with behavioral support is an effective treatment for patients with chronic, disabling low-back pain, as measured by self-assessments, physical capacities, and return to work.