Analysis of OGO-6 observations of the 0 I 5577A tropical nightglow

Atomic oxygen green line data from the horizon scanning photometer on OGO-6 was examined. Unfolding the satellite data from the tropical F-region yields altitude and latitude variations of the O(1S) emissions. The spatial variations of the tropical F-region electron density are then calculated by assuming dissociative recombination and using a model atmosphere. Where comparisons to ground-based data are possible the results are good. Thus, the satellite observations constitute a form of topside sounding of the ionosphere below the F-peak and provide synoptic data about this portion of the ionsphere otherwise impractical to obtain

Mechanical Loading Attenuates Radiation-Induced Bone Loss in Bone Marrow Transplanted Mice

Exposure of bone to ionizing radiation, as occurs during radiotherapy for some localized malignancies and blood or bone marrow cancers, as well as during space travel, incites dose-dependent bone morbidity and increased fracture risk. Rapid trabecular and endosteal bone loss reflects acutely increased osteoclastic resorption as well as decreased bone formation due to depletion of osteoprogenitors. Because of this dysregulation of bone turnover, bone’s capacity to respond to a mechanical loading stimulus in the aftermath of irradiation is unknown. We employed a mouse model of total body irradiation and bone marrow transplantation simulating treatment of hematologic cancers, hypothesizing that compression loading would attenuate bone loss. Furthermore, we hypothesized that loading would upregulate donor cell presence in loaded tibias due to increased engraftment and proliferation. We lethally irradiated 16 female C57Bl/6J mice at age 16 wks with 10.75 Gy, then IV-injected 20 million GFP(+) total bone marrow cells. That same day, we initiated 3 wks compression loading (1200 cycles 5x/wk, 10 N) in the right tibia of 10 of these mice while 6 mice were irradiated, non-mechanically-loaded controls. As anticipated, before-and-after microCT scans demonstrated loss of trabecular bone (-48.2% Tb.BV/TV) and cortical thickness (-8.3%) at 3 wks following irradiation. However, loaded bones lost 31% less Tb.BV/TV and 8% less cortical thickness (both p\u3c0.001). Loaded bones also had significant increases in trabecular thickness and tissue mineral densities from baseline. Mechanical loading did not affect donor cell engraftment. Importantly, these results demonstrate that both cortical and trabecular bone exposed to high-dose therapeutic radiation remain capable of an anabolic response to mechanical loading. These findings inform our management of bone health in cases of radiation exposure

The Sedimentary Petrography of the Oil and Gas Producing Horizons in Montana

Montana is an excellent oil province, as oil and gas are pro­duced from a wider range of beds in the geologic section than in any other district in the United States. (1,864) Commercial fields have been developed in Ordovician, Devonian, Mississippian, Pennsylvanian, Jurassic, Lower Cretaceous, and Upper Cretaceous. It is believed that by describing the physical characteristics of the producing horizons, and by placing this information in one compact volume, a better under­standing of oil and gas occurrence in Montana may be gained

Microgrids: Applications, Solutions, Case Studies, and Demonstrations

Rapid urbanization of the world’s population is creating great sociological, environmental, and structural strains on the cities where people are moving to. Housing is becoming scarce and expensive, while the need to build new housing is placing great burdens on existing infrastructure—especially local power grids. It will be shown that integrating urban development around a microgrid concept would greatly alleviate the problems associated with urbanization. Incorporation of a microgrid, based on a cogenerating power station where waste heat is used to provide climate control and hot water and where power production is supplemented with renewable energy sources, would effectively remove the development from the local grid and greatly reduce greenhouse gas emissions. Additionally, this model can accommodate any combination of large-scale residential, commercial, or industrial developments to revitalize the local neighborhood and can do so at a level of profit that would allow for lower rents, creating housing and job opportunities for those who are most in need

The Call Of The U. S. A. : One Step

https://digitalcommons.library.umaine.edu/mmb-vp/4168/thumbnail.jp