176 research outputs found
1922 Discovery of Mysterious Prehistoric Carved Stone Near Park Boundary
A 14 page booklet of photographs and information regarding the discovery of a prehistoric carved stone found near the southwest corner of Rocky Mountain National Park in 1922. The legitimacy of the carved stone is contested by various experts in the field.
Housed in National Archives at Denver; Record Group 79, Records of the National Park Service; Rocky Mountain National Park, General Correspondence 1918-1954; Box 4, Folder: 740 Antiquitie
Use of Thermoregulatory Models to Enhance Space Shuttle and Space Station operations and Review of Human Thermoregulatory Control
Thermoregulation in the space environment is critical for survival, especially in off- nominal operations. In such cases, mathematical models of thermoregulation are frequently employed to evaluate safety-of-flight issues in various human mission scenarious. In this study, the 225-node Wissler model and the 41-Node Metabolic Man model are employed to evaluate the effects of such a scenario. Metabolic loads on astronauts wearing the advanced crew escape suit (ACES) and liquid cooled ventilation garment (LCVG) are imposed on astronauts exposed to elevated cabin temperatures resulting from a systems failure. The study indicates that the performance of the ACES/LCVG cooling system is marginal. Increases in workload and or cabin temperature above nominal will increase rectal temperature, stored heat load, heart rate, and sweating, which could lead to deficits in the performance of cognitive and motor tasks. This is of concern as the ACES/LCVG is employed during Shuttle decent when the likelihood of a safe landing may be compromised. The study indicates that the most effective mitigation strategy would be to decrease the LCVG inlet temperature
The life cycle of Drosophila orphan genes
Orphans are genes restricted to a single phylogenetic lineage and emerge at
high rates. While this predicts an accumulation of genes, the gene number has
remained remarkably constant through evolution. This paradox has not yet been
resolved. Because orphan genes have been mainly analyzed over long evolutionary
time scales, orphan loss has remained unexplored. Here we study the patterns of
orphan turnover among close relatives in the Drosophila obscura group. We show
that orphans are not only emerging at a high rate, but that they are also
rapidly lost. Interestingly, recently emerged orphans are more likely to be
lost than older ones. Furthermore, highly expressed orphans with a strong
male-bias are more likely to be retained. Since both lost and retained orphans
show similar evolutionary signatures of functional conservation, we propose
that orphan loss is not driven by high rates of sequence evolution, but
reflects lineage specific functional requirements.Comment: 47 pages, 19 figure
The American Indian: An introduction to the anthropology of the new world
RefereedSecond editio
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