Brayton-cycle radioisotope heat-source design study. Phase II /preliminary design/ report

Brayton cycle radioisotope heat source desig

Building a Participatory Culture: Collaborating with Student Organizations for Twenty-first Century Library Instruction

Today’s students are critical thinkers, collaborators, and creators. They expect to participate in twenty-first century learning environments not as passive information consumers (think lectures), but as active contributors (think team-based problem-solving). There are opportunities for instruction librarians to collaborate directly with student-led organizations. These partnerships have the potential to increase attendance at library events and provide platforms for students to engage in richer forms of exploratory learning that incorporate twenty-first century skills. This article will discuss the literature surrounding library instruction collaborations, identify “Librarian–Student Organization Collaborations” as an important form of partnership, and supply specific case studies of successful library instruction events based on these collaborations

Brayton-cycle radioisotope heat source design study. Phase I - /Conceptual design/ report

Conceptual designs for radioisotope heat source systems to provide 25 kW thermal power to Brayton cycle power conversion system for space application

Structure of the western Somali Basin

Originally issued as Reference No. 67-38, series later renamed WHOI-. Reprint from Journal of Geophysical Research, vol. 72, no. 10, May 1967.The western Somali Basin in the northwestern Indian Ocean is covered by thick deposits of terrigenous sediments. Seismic reflection profiles show, however, the northern and southern parts to be very different. The northern sections is a deep basin filled with thick uniformly stratified sediments. It is enclosed by the continental margin to the west and north, Chain ridge to the east, and shallow basement structure to the south. A change in depth of basement occurs along an approximately east-west line at latitude 3°30'N very near the southern end of Chain ridge. In the southern portion of the basin the basement is shallow, and, immediately south of latitude 3°30'N, it has high relief. Stratified flat-lying sediments fill the basement depressions, and isolated hills formed of basement material rise above the abyssal plain deposits. Farther to the south the abyssal plain becomes very narrow. Gabbro dredged from the southeast slope of Chain ridge has been dated by the potassium-argon method as 89.6 ± 4.5 m.y., which should be considered a minimum age. The evidence suggests that the entire sediment sequence of the northern basin was deposited subsequent to the formation of the ridge. The thin sediment cover of the southern portion of the basin is probably no older than Tertiary.Office of Naval Research under contract Nonr-4029(00) NR 260-101

Sediment Sorting and Rounding in a Basaltic Glacio-Fluvio-Aeolian Environment: hrisjkull Glacier, Iceland

Sediments and sedimentary rocks preserve a rich history of environment and climate. Identifying these signals requires an understanding of the physical and chemical processes that have affected sedimentary deposits [1]. Such processes include sorting and rounding during transport and chemical alteration through weathering and diagenesis. Although these processes have long been studied in quartz-dominated sedimentary systems [2], a lack of studies of basaltic sedimentary systems limits our interpretations of the environment and climate where mafic source rocks dominate, such as on Mars [3,4]. As part of the SAND-E: Semi-Autonomous Navigation for Detrital Environments project [5], which uses robotic operations to examine physical and chemical changes to sediments in basaltic glacio-fluvialaeolian environments, this research studies changes in sorting and rounding of fluvial-aeolian sediments along a glacier-proximal-to-glacier-distal transect in the outwash-plain of the risjkull glacier in SW Iceland (Fig. 1

Naturally occurring Ehrlichia chaffeensis infection in coyotes from Oklahoma.

A nested polymerase chain reaction assay was used to determine the presence of Ehrlichia chaffeensis, E. canis, and E. ewingii DNA in blood samples of free-ranging coyotes from central and northcentral Oklahoma. Of the 21 coyotes examined, 15 (71%) were positive for E. chaffeensis DNA; none was positive for E. canis or E. ewingii. Results suggest that E. chaffeensis infections are common in free-ranging coyotes in Oklahoma and that these wild canids could play a role in the epidemiology of human monocytotropic ehrlichiosis

Thermal recrystallization of alpha-recoil damaged minerals of the pyrochlore structure type

Thermal recrystallization effects (heat of recrystallization and identification of phases formed), have been determined for naturally occurring members of the pyrochlore group which have received alpha doses of up to 4 X 10{sup 16} alphas/mg. The heats of recrystallization, E{sub t}, range from 125 to 210 J/g. Release of energy decreases as a function of crystallinity (estimated on the basis of the intensity of x-ray diffraction maxima), with the fully-metamict samples approaching 210 J/g. Lower measured values (40-125 J/g) are the result of alteration of the pyrochlores. Other metamict, complex oxides with stoichiometries of ABO{sub 4} and AB{sub 2}O{sub 6} have lower heats of recrystallization (40-85 J/g), and are easily distinguished from pyrochlore group minerals. Activation energies of recrystallization, E{sub a}, range between values of 0.29 to 0.97 eV, less than those measured for Pu-doped, synthetic zirconolites

Effect of pancreatic and/or renal transplantation on diabetic autonomic neuropathy

Thirty-nine Type 1 (insulin-dependent) diabetic patients were studied prospectively after simultaneous pancreas and kidney (n=26) and kidney grafting alone (n=13) by measuring heart rate variation during various manoeuvers and answering a standardized questionnaire every 6 to 12 months post-transplant. While age, duration of diabetes, and serum creatinine (168.1±35.4 vs 132.7±17.7 mgrmol/l) were comparable, haemoglobin A1 levels were significantly lower (6.6±0.2 vs 8.5±0.3%; p<0.01) and the mean observation time longer (35±2 vs 25±3 months; p<0.05) in the pancreas recipients when compared with kidney transplanted patients. Heart rate variation during deep breathing, lying/standing and Valsalva manoeuver were very similar in both groups initially and did not improve during follow-up. However, there was a significant reduction in heart rate in the pancreas recipient group. Autonomic symptoms of the gastrointestinal and thermoregulatory system improved more in the pancreas grafted subjects, while hypoglycaemia unawareness deteriorated in the kidney recipients. This study suggests that long-term normoglycaemia by successful pancreatic grafting is able to halt the progression of autonomic dysfunction