Robust radiocarbon dating of wood samples by high-sensitivity liquid scintillation spectroscopy in the 50–70 kyr age range

Although high-sensitivity liquid scintillation (LS) spectroscopy is theoretically capable of producing finite radiocarbon ages in the 50,000- to 70,000-yr range, there is little evidence in the literature that meaningful dates in this time period have been obtained. The pressing need to undertake calibration beyond 26 kyr has resulted in the regular publication of ¹⁴C results in excess of 50 kyr, yet very little effort has been made to demonstrate their accuracy or precision. There is a paucity of systematic studies of the techniques required to produce reliable dates close to background and the methods needed to assess contamination from either in situ sources or laboratory handling and processing. We have studied the requirements for producing accurate and reliable dates beyond 50 kyr. Laboratory procedures include optimization of LS spectrometers to obtain low and stable non-¹⁴C background count rates, use of low-background counting vials, large benzene volumes, long counting times, and preconditioning of vacuum lines. We also discuss the need for multiple analyses of a suitable material containing no original ¹⁴C (background blank) and the application of an appropriate statistical model to compensate for variability in background contamination beyond counting statistics. Accurate and reproducible finite ages >60 kyr are indeed possible by high-sensitivity LS spectroscopy, but require corroborating background blank data to be defensible

A Status Study of Business and Office Occupations Education in the Community Colleges of Washington State

The purpose of this study was to determine the status of business and office education in the community colleges of the State of Washington in the areas of (1) curricula, (2) plant facilities and equipment, (3) instructional personnel, and (4) student enrollment

The effect of various cognitive strategies in the control of public speaking anxiety

An experiment was designed to apply the cognitive strategy paradigm of Jaremko and Patteson to a classroom speech anxiety situation. Forty-eight introductory speech students volunteered to be tested on physiological, behavioral, and self-report measures of anxiety during two of their regular classroom speeches. Subjects were divided into groups based upon which cognitive strategy they were asked to implement: rationalization, reversal of affect, misattribution, misattribution and rationalization, a placebo control and a no treatment control. Results indicated reductions in anxiety across trials, but these were not attributable to treatment. These findings are discussed in terms of the application of laboratory paradigms to field situations, and the reliability of anxiety measures. Future lines of research are suggested

Neighborhood diversity and the creative class in Chicago

Richard Florida\u27s creative class theory posits that highly skilled workers with creative- or knowledge-intensive occupations are particularly sensitive to ‘quality of place’, a key component of which is an open and tolerant attitude toward different peoples, cultures, and lifestyles. While diversity, as a proxy for tolerance, has proven to be a relatively weak pull-factor at the inter-metropolitan level, the potential role of neighborhood-level diversity in the residential location of creative class workers has yet to be explored empirically. In this study we use ordinary least squares (OLS) regression and geographically weighted regression (GWR) to test the hypothesis that there exists significant associations between particular types of neighborhood diversity (i.e., sexual orientation, language, race, and income) and the proportion of workers with specific creative class occupations. The results of our Chicago case study suggest a significant positive relationship between the creative class and the proportion of gay households and income diversity, but not racial or linguistic diversity. Overall, diversity appears to play a limited role in predicting where creative class workers reside, though the GWR analysis indicated substantial spatial variation in the strength of association between neighborhood diversity and creative class share across the study area

Interview with Pauline Gillmore

An interview with Pauline Gillmore regarding her experiences in a one-room school house.https://scholars.fhsu.edu/ors/1044/thumbnail.jp