3,240 research outputs found
Database Analysis to Support Nutrient Criteria Development (Phase I)
The intent of this publication of the Arkansas Water Resources Center is to provide a location whereby a final report on water research to a funding agency can be archived. The Texas Commission on Environmental Quality (TCEQ) contracted with University of Arkansas researchers for a multiple year project titled “Database Analysis to Support Nutrient Criteria Development”. This publication covers the first of three phases of that project and has maintained the original format of the report as submitted to TCEQ. This report can be cited either as an AWRC publication (see below) or directly as the final report to TCEQ
Neogene benthic foraminiferal stratigraphy and deep water history of Sites 645, 646, and 647, Baffin Bay and Labrador Sea
Benthic foraminifers were examined from Neogene sediments of Ocean Drilling Program (ODP) Sites 645, 646, and
647 to determine their biostratigraphy and to place constraints on the paleoceanographic history of Baffin Bay, Eirik Ridge, and the Gloria Drift. At Site 645 in Baffin Bay, a Pleistocene Stetsonia assemblage is similar to the modern Baffin Bay assemblage, but an underlying Epistominella takayanagii assemblage has no modern analog. Miocene assemblages below a barren interval display low diversity and consist mainly of agglutinated species.
At Site 646 in the Labrador Sea, benthic faunal turnovers occur near important seismic horizons. A Miocene
Nuttallides umbonifera assemblage similar to assemblages at other North Atlantic sites occurs below reflector R3.
Above reflector R3, a coarse agglutinated assemblage containing more diversified calcareous benthic foraminifers was found that displays affinity to assemblages in the Norwegian-Greenland Sea. The faunal turnover near reflector R3 was interpreted as reflecting the onset (or renewal) of significant Denmark Straits Overflow Water at Site 646 at ~7.5 Ma, Agglutinated species disappear between reflector R2 and the base of the sediment drift, indicating a change in deep-water properties that occurred at ~ 4.7 Ma. This turnover ultimately may be linked to the reopening of the Mediterranean. The beginning of drift sedimentation at the Eirik Ridge is dated at —4.5 Ma. Drift formation ceased at ~2.5 Ma, concomitant with the appearance of ice-rafted sediments. Pleistocene assemblages containing Stetsonia horvathi display affinity to deep assemblages in high-latitude ocean basins. Upper Pliocene and Pleistocene benthic assemblages at Site 647 contain N. umbonifera, which indicates a continued influence of corrosive deep water at the Gloria Drift
Experiences of Prejudice and Isolation at a Predominantly White, Great Plains University
This session discusses results from a qualitative study examining the experiences and isolation of Students of Color and GLBT students at a Great Plains University. Over 61 percent of respondents had experienced prejudice. In addition, students saw minority status as both an isolating factor and a source of solidarity
Existential Anthropology and the Transformation of the Existential Situation into Religious Meaning: The Rise and Similarities of Religion and the Arts
The social forming elements to the existential situation provide the basis from which springs all things human, where seemingly disparate functions within the social dynamic—in this instance, art and religion—find common genesis. An aspect of the existential situation is the development of complete memory and awareness because of the human state of physical vulnerability. In the following essay, starting with remembrance, we will see how the existential complex itself helps to form notions of art and religion; how impediment-to-will and exertion become essential elements to the formulation of religious ritual and fashion; and finally, we will take a look at the part worship itself plays in the performing arts
The early medieval origin of Perth, Scotland
The radiocarbon results (and Bayesian modeling) of 15 samples of carbonized food residues removed from the external surface of rim sherds of cooking pots indicate that shellyware pottery first appeared in Perth, Scotland, around cal AD 9101020 (95% probability) and that it had disappeared by cal AD 10201140 (95% probability). Previously, it had been suggested that this pottery could not date to before AD 1150. These data, together with 14C analyses carried out on leather artifacts and a sample of wattle from a ditch lining, also demonstrate that there was occupation in Perth about 100 yr or more prior to the granting of royal burgh status to Perth in the 1120s
Ancilla models for quantum operations: For what unitaries does the ancilla state have to be physical?
Any evolution described by a completely positive trace-preserving linear map
can be imagined as arising from the interaction of the evolving system with an
initially uncorrelated ancilla. The interaction is given by a joint unitary
operator, acting on the system and the ancilla. Here we study the properties
such a unitary operator must have in order to force the choice of a physical-
that is, positive-state for the ancilla if the end result is to be a
physical-that is, completely positive-evolution of the system.Comment: Quantum Information Processing, (2012
Impulse-driven surface breakdown data : a Weibull statistical analysis
Surface breakdown of oil-immersed solids chosen to insulate high-voltage, pulsed-power systems is a problem that can lead to catastrophic failure. Statistical analysis of the breakdown voltages, or times, associated with such liquid-solid interfaces can reveal useful information to aid system designers in the selection of solid materials. Described in this paper are the results of a Weibull statistical analysis, applied to both breakdown-voltage data and time-to-breakdown data generated in gaps consisting of five different solid polymers immersed in mineral oil. Values of the location parameter γ provide an estimate of the applied voltage below which breakdown will not occur, and under uniform-field conditions, γ varied from 192 kV (480 kV/cm) for polypropylene to zero for ultra-high molecular weight polyethylene. Longer times to breakdown were measured for UHMWPE when compared with the other materials. However, high values of the shape parameter β reported in the present paper suggest greater sensitivity to an increase in applied voltage – that is, the probability of breakdown increases more sharply with increasing applied voltage for UHMWPE compared to the other materials. Analysing peak-applied-voltage data, only PP consistently reflected a low value of β across the different sets of test conditions. In general, longer mean times to breakdown were found for solid materials of εr more closely matched to that of the surrounding mineral oi
Gene-flow between populations of cotton bollworm Helicoverpa armigera (Lepidoptera: Noctuidae) is highly variable between years
Both large and small scale migrations of Helicoverpa armigera Hübner in Australia were investigated using AMOVA analysis and genetic assignment tests. Five microsatellite loci were screened across 3142 individuals from 16 localities in eight major cotton and grain growing regions within Australia, over a 38-month period (November 1999 to January 2003). From November 1999 to March 2001 relatively low levels of migration were characterized between growing regions. Substantially higher than average gene-flow rates and limited differentiation between cropping regions characterized the period from April 2001 to March 2002. A reduced migration rate in the year from April 2002 to March 2003 resulted in significant genetic structuring between cropping regions. This differentiation was established within two or three generations. Genetic drift alone is unlikely to drive genetic differentiation over such a small number of generations, unless it is accompanied by extreme bottlenecks and/or selection. Helicoverpa armigera in Australia demonstrated isolation by distance, so immigration into cropping regions is more likely to come from nearby regions than from afar. This effect was most pronounced in years with limited migration. However, there is evidence of long distance dispersal events in periods of high migration (April 2001–March 2002). The implications of highly variable migration patterns for resistance management are considered.K.D. Scott, K.S. Wilkinson, N. Lawrence, C.L. Lange, L.J. Scott, M.A. Merritt, A.J. Lowe and G.C Graha
Teaching Introductory Psychology in the Community College Classroom: Enhancing Student Understanding and Retention of Essential Information
Here the authors describe a study conducted to determine whether a “Test Yourself” procedure, administered either before or after a lecture, might improve students’ retention of the information, as well as stimulate critical thinking
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