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Issue Brief: European Americans and Native Americans
This issue brief examines the relationship between European/White Americans and Native Americans. Complicated even to the present day, the relationship between these two groups has historically been one of oppressor versus oppressed, a dichotomy that has since evolved but which serves to shed light on the intricacies of the contemporary Native American experience in comparison to that of white America
Space Station Centrifuge: A Requirement for Life Science Research
A centrifuge with the largest diameter that can be accommodated on Space Station Freedom is required to conduct life science research in the microgravity environment of space. (This was one of the findings of a group of life scientists convened at the University of California, Davis, by Ames Research Center.) The centrifuge will be used as a research tool to understand how gravity affects biological processes; to provide an on-orbit one-g control; and to assess the efficacy of using artificial gravity to counteract the deleterious biological effect of space flight. The rationale for the recommendation and examples of using ground-based centrifugation for animal and plant acceleration studies are presented. Included are four appendixes and an extensive bibliography of hypergravity studies
Historical reconstruction of the Atlantic Meridional Overturning Circulation from the ECMWF operational ocean reanalysis
A reconstruction of the Atlantic Meridional Overturning Circulation (MOC) for the period 1959–2006 has been derived from the ECMWF operational ocean reanalysis. The reconstruction shows a wide range of time-variability, including a downward trend. At 26N, both the MOC intensity and changes in its vertical structure are in good agreement with previous estimates based on trans-Atlantic surveys. At 50N, the MOC and strength of the subpolar gyre are correlated at interannual time scales, but show opposite secular trends. Heat transport variability is highly correlated with the MOC but shows a smaller trend due to the warming of the upper ocean, which partially compensates for the weakening of the circulation. Results from sensitivity experiments show that although the time-varying upper boundary forcing provides useful MOC information, the sequential assimilation of ocean data further improves the MOC estimation by increasing both the mean and the time variability
A measurement of the energy spectra of cosmic rays from 20 to 1000 GeV per AMU
During the report period the BUGS-4 instrument was completed, and the maiden voyage took place on 29 September from Fort Sumner, New Mexico. The successful flight of a large spherical drift chamber is a unique first for the sub-orbital balloon program. Unfortunately the instrument was consumed by fire after striking a power line during landing. However, while at float altitude, circa 24 hours of data were telemetered. The pre-flight preparations, and flight operations are described
Darwinian Selection and Non-existence of Nash Equilibria
We study selection acting on phenotype in a collection of agents playing
local games lacking Nash equilibria. After each cycle one of the agents losing
most games is replaced by a new agent with new random strategy and game
partner. The network generated can be considered critical in the sense that the
lifetimes of the agents is power law distributed. The longest surviving agents
are those with the lowest absolute score per time step. The emergent ecology is
characterized by a broad range of behaviors. Nevertheless, the agents tend to
be similar to their opponents in terms of performance.Comment: 4 pages, 5 figure
Cosmic Ray Energy Determination by the Reduced-Opening Angle Method
Accurate measurement of the primary galactic cosmic ray species energy dependence in the regime beyond approx. 500 GeV/a is difficult due to the low flux and the limitations of energy measurement techniques. However, such observations are essential to resolve several questions of current interest such as: Is the enrichment of heavy species (Z greater that or equal to 6) cosmic rays first reported at higher energies by the proton satellite' and then later at lower energies real? The results from a previous deployment of the reduced opening angle technique are inconclusive but the authors do point to limitations in the previous techniques. Another intriguing puzzle is the energy dependence of silicon cosmic rays. Two independent experiments using different experimental techniques indicate that silicon is under-abundant. At present the observation is limited by statistics; it could still be a three sigma fluctuation. However, if confirmed the current models of acceleration and propagation which are species independent are seriously inadequate. To progress further the species and energy dependence must be accurately measured in a manner that is free from systematic uncertainty. In this report we show that the reduced opening angle method offers a simple and relatively inexpensive method to answer these questions. First we present the physics of the reduced opening angle and indicate the expected energy and charge resolution. The proposed detector design is then presented followed by the expected performance. Where ever possible simple phenomenological expressions that allow 'back of the envelope' estimates are given. More details are presented in the appendices. The limit of the energy resolution and the expected event rates for iron cosmic rays are calculated. Salient points are summarized in the conclusions
Earthquake swarm in the Santa Barbara Channel, California, 1968
Sixty-three minor earthquakes (maximum magnitude = 5.2) occurred in the Santa Barbara Channel during the period June 26 to August 3 1968. The epicenters form a shot-scatter pattern upon a broad, high-standing fault block in the channel midway between Santa Cruz Island and the City of Santa Barbara. Focal mechanism studies indicate that oblique-slip movement occurred along a northwest-striking fault even though the major folds and faults strike nearly east-west. Preliminary studies of the areal hydrocarbon production data show no compelling evidence for a causal relationship with the swarm
Temporal Foraging Patterns of Nonnative Frogs (Eleutherodactylus Coqui) in Hawaii
The Puerto Rican Coqui Frog (Eleutherodactylus coqui) is a nocturnal, invasive species that was introduced into Hawaii in the 1980s. Because they reach extremely high densities (up to 90,000 frogs/ha), they have the potential to affect invertebrate prey communities. Previously, researchers used frogs collected only at night to characterize their prey. Because Coquis use retreat sites near the forest floor during the day and understory perch sites at night, frogs collected at night might show different amounts and types of prey than would frogs collected in the morning. We analyzed stomach contents of 435 frogs collected in the morning (0300–0600 h) and at night (1900–2200 h) from five sites on the island of Hawaii. Frogs collected in the morning had 1.7 times more prey items and 2.1 times greater prey volume than those collected at night; however, prey composition did not differ between morning- and evening-collected frogs. Across sites, Formicidae (ants) and Amphipoda (amphipods) were the dominant prey, and at least 61.6% of their prey items were nonnative species. Across sites, morning- and evening-collected stomach contents were not different from environmental samples of leaflitter invertebrates but were different from environmental samples of foliage and flying invertebrates, suggesting that Coquis forage primarily in the leaf litter throughout the night. Previous research that investigated stomach contents of frogs collected only at night greatly underestimated the number and volume of prey items that Coquis consume during the entire foraging period but accurately described their primary prey: nonnative, leaf-litter invertebrates
Common Rocks, Minerals and Fossils Found in Indiana
Indiana Geological Survey Circular 3Rocks, minerals, and fossils of Indiana are the foundation, directly or indirectly, of the economic well-being of the state. Utilization of rocks, minerals, and fossils has contributed to the development of civilization. Those persons who have the ability, initiative, and vigor to utilize the earth's mineral resources advantageously are most likely to progress and prosper.
One of the responsibilities of the Indiana Geological Survey is the investigation of mineral wealth within the state. Not only should the citizens of Indiana be informed about these resources, but also people in other states should know that Indiana is a mining, as well as an agricultural and a manufacturing, state.
Because of rather extensive exploitation of limestone, dolomite, clay) shale, sand, gravel, coal, water, and oil resources in Indiana, more people are becoming aware that the science of geology exists and that much can be gained by an understanding of it. The interest of Hoosiers) as well as other people, in Indiana's rocks, minerals, and fossils is revealed both by the many inquiries received by the Geological Survey for information concerning Indiana's mineral resources and by the specimen samples sent to the Survey for identification. This circular has been prepared, therefore, primarily to accompany a set of common rocks, minerals, and fossils found in Indiana. These specimens are described in some detail in nontechnical terms in order that students in secondary schools, amateur collectors, scout organizations, and other interested persons and groups can become familiar with them.
The authors can neither cover fully in this brief report all characteristics and variations of any given specimen nor describe in detail the infinite varieties of each rock, mineral, and fossil found in Indiana. For special information regarding Indiana geology, the reader should consult the more detailed reports of the Geological Survey and its predecessors. The staff of the Indiana Geological Survey hope that the study of specimen rocks, minerals, and fossils. will help in answering some of the questions about Indiana geology.Indiana Department of Conservatio
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