An international team of researchers show how high-precision radiocarbon dating is liberating us from chronological assumptions based on Biblical research. Surface and topographic mapping at the large copper-working site of Khirbat en-Nahas was followed by stratigraphic excavations at an ancient fortress and two metal processing facilities located on the site surface. The results were spectacular. Occupation begins here in the eleventh century BC and the monumental fortress is built in the tenth. If this site can be equated with the rise of the Biblical kingdom of Edom it can now be seen to: have its roots in local Iron Age societies; is considerably earlier than previous scholars assumed; and proves that complex societies existed in Edom long before the influence of Assyrian imperialism was felt in the region from the eighth – sixth centuries BC.
Accidental exposure to depleted or enriched uranium may occur in a variety of circumstances. There is a need to quantify such exposure, with the possibility that the testing may post-date exposure by months or years. Therefore, it is important to develop a very sensitive test to measure precisely the isotopic composition of uranium in urine at low levels of concentration. The results of an interlaboratory comparison using sector field (SF)-inductively coupled plasma-mass spectrometry (ICP-MS) and multiple collector (MC)-ICP-MS for the measurement of uranium concentration and U/U and U/U isotopic ratios of human urine samples are presented. Three urine samples were verified to contain uranium at 1-5 ng L and shown to have natural uranium isotopic composition. Portions of these urine batches were doped with depleted uranium (DU) containing small quantities of U, and the solutions were split into 100 mL and 400 mL aliquots that were subsequently measured blind by three laboratories. All methods investigated were able to measure accurately U/U with precisions of approximately 0.5% to approximately 4%, but only selected MC-ICP-MS methods were capable of consistently analyzing U/U to reasonable precision at the approximately 20 fg L level of U abundance. Isotope dilution using a U tracer demonstrates the ability to measure concentrations to better than +/-4% with the MC-ICP-MS method, though sample heterogeneity in urine samples was shown to be problematic in some cases. MC-ICP-MS outperformed SF-ICP-MS methods, as was expected. The MC-ICP-MS methodology described is capable of measuring to approximately 1% precision the U/U of any sample of human urine over the entire range of uranium abundance down to <1 ng L, and detecting very small amounts of DU contained therein.
This article examines the origins and development of citizenship and equal rights by the Reconstruction Congress (1865-1875) to determine if it created a new constitutional order that is color blind and thus prohibits the use of racial classifications by government to achieve school desegregation and affirmative action programs. The theory of color-blind constitutionalism, although pursued relentlessly by a small cadre of radical Republicans, stood in marked contrast to the views of the moderate-conservative majority, a group virtually obsessed with the ways in which race affected fundamental questions of citizenship, civil equality, and political power. Only through a multiethnic history can we comprehend the variegated and profound ways in which racial ideology shaped the beliefs and behavior of the Reconstruction Congress and the ways in which Congress carefully crafted the meaning and intent of citizenship and equality in the new constitutional order, one that serves as the legal foundation for contemporary debates over race-conscious educational policies.
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