1000 resultados para 171-1053
Resumo:
Global cooling and the development of continental-scale Antarctic glaciation occurred in the late middle Eocene to early Oligocene (~38 to 28 million years ago), accompanied by deep-ocean reorganization attributed to gradual Antarctic Circumpolar Current (ACC) development. Our benthic foraminiferal stable isotope comparisons show that a large d13C offset developed between mid-depth (~600 meters) and deep (>1000 meters) western North Atlantic waters in the early Oligocene, indicating the development of intermediate-depth d13C and O2 minima closely linked in the modern ocean to northward incursion of Antarctic Intermediate Water. At the same time, the ocean's coldest waters became restricted to south of the ACC, probably forming a bottom-ocean layer, as in the modern ocean. We show that the modern four-layer ocean structure (surface, intermediate, deep, and bottom waters) developed during the early Oligocene as a consequence of the ACC.
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More than 50 discrete volcanic ash layers were recovered at the five drill sites of the Blake Nose depth transect (Leg 171B, western central Atlantic). The majority of these ash layers are intercalated with Eocene hemipelagic sediments with a pronounced frequency maximum in the upper Eocene. Several ash layers appear to be deposited from volcanic fallout with little or no indication of secondary remobilization. They provide excellent stratigraphic markers for a correlation of the Leg 171B drill sites. Other ash layers were probably redeposited from volcaniclastic-rich turbidity currents, but they still represent geologically instantaneous events that can be used in stratigraphic correlation between adjacent drill holes. Additional nonvolcanic marker beds, like the suspect late Eocene impact event layer, were included in our hole-to-hole correlations. Stratigraphic and downcore positions of marker beds were compiled and plotted against existing composite depth records that were constructed to guide high-resolution sampling. Comparison of our correlation with the spliced composite sections of each drill site reveals several minor and some major discrepancies. These may result from drilling distortion or missing sections, from the lack of unambiguous criteria for the synchronism of ash layers, or from the systematic exclusion of marker-bed data in the construction of the spliced record. Integration of both correlation approaches will help eliminate most of the observed discrepancies.
Resumo:
Descripció de l' evolució del llinatge dels senyors de Cervià i la fundació del monestir benedictí de Sta. Maria de Cervià l'any 1053 i de la canònica de Sta. Maria de Vilabertran l'any 1069 en el context de la societat catalana del segle XI
Resumo:
Bureau of Nutrition and Health Promotion part of the Iowa Department of Public Health produces of weekly newsletter about the Iowa WIC Program for the State of Iowa citizen.
Resumo:
Earthen fills and back slopes resulting from highway building and other construction projects pose problems with respect to erosion stabilization and establishing vegetation cover. Sediments from such slopes create stream pollution while the erosion itself results in maintenance problems. Furthermore, adverse conditions aggravated by erosion prevent satisfactory establishing of vegetative cover. A dense vegetative cover is very effective in controlling erosion but even with optimum weather and soil conditions there is a delay of about 10 weeks between seeding and the establishment of a vegetative cover. Under actual field conditions, 3 months to a year may elapse between completion of construction and establishment of a vegetative cover. A research project was initiated early in 1974 to determine the effectiveness of a rock mulch of crushed limestone aggregates in controlling soil losses on highway construction back slopes in Iowa and to find the influence of such treatments on stand establishment of grasses and legumes.
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This report presents an overview of where the computerized highway information system is now, and its status as a planning and programming tool for state highway agencies. A computerized highway information system is simply a computer linked system which can be used by many divisions of a transportation agency to obtain information to meet data reporting, analyses or other informational needs. The description of the highway information system includes: current use and status, applications, organization and system development, benefits and problems.
Resumo:
Scholarship on the American Slave South generally agrees that John Eliot Cairnes's The Slave Power provided a highly biased interpretation of the functioning and long-term viability of the southern slave economy. Published shortly after the outbreak of the Civil War, its partisanship is partly attributed to its clearly stated goal to shift British support from the secession states to the states of the Union. Thus, it is generally agreed, Cairnes sifted his sources to obtain the desired outcome. A more balanced use of the sources at his possession would have provided a very different outcome. This paper will challenge this general assessment of Cairnes's book by examining in some detail two of Cairnes's most important sources: Frederic Law Olmsted's travelogues on the American Slave South and James D. B. De Bow's compilation of statistical data and essays in his Industrial Resources, etc., of the Southern and Western States (1852-53). By contrasting De Bow's use of statistical evidence with Olmsted's travelogues, my final purpose is to question the weight of evidence on the American Slave South. Cairnes aimed, I will argue, much more to balance the evidence than is generally acknowledged, but it is misleading to think that balancing a wide range of evidence washes out bias if this evidence itself is politically skewed, as is the rule rather than the exception.
Resumo:
This study main purpose was the validation of both French and German versions of a Perceived Neighborhood Social Cohesion Questionnaire. The sample group comprised 5065 Swiss men from the "Cohort Study on Substance Use Risk Factors." Multigroup Confirmatory factor analysis showed that a three-factor model fits the data well, which substantiates the generalizability of Perceived Neighborhood Social Cohesion Questionnaire factor structure, regardless of the language. The Perceived Neighborhood Social Cohesion Questionnaire demonstrated excellent homogeneity (α = 95) and split-half reliability (r = .96). The Perceived Neighborhood Social Cohesion Questionnaire was sensitive to community size and participants' financial situation, confirming that it also measures real social conditions. Finally, weak but frequent correlations between Perceived Neighborhood Social Cohesion Questionnaire and alcohol, cigarette, and cannabis dependence were measured.
Resumo:
Soitinnus: cembalo, jousiorkesteri.