Interdisciplinary approach to the demography of Jamaica

<p>Background: The trans-Atlantic slave trade dramatically changed the demographic makeup of the New World, with varying regions of the African coast exploited differently over roughly a 400 year period. When compared to the discrete mitochondrial haplotype distribution of historically appropriate source populations, the unique distribution within a specific source population can prove insightful in estimating the contribution of each population. Here, we analyzed the first hypervariable region of mitochondrial DNA in a sample from the Caribbean island of Jamaica and compared it to aggregated populations in Africa divided according to historiographically defined segments of the continent's coastline. The results from these admixture procedures were then compared to the wealth of historic knowledge surrounding the disembarkation of Africans on the island.</p> <p>Results: In line with previous findings, the matriline of Jamaica is almost entirely of West African descent. Results from the admixture analyses suggest modern Jamaicans share a closer affinity with groups from the Gold Coast and Bight of Benin despite high mortality, low fecundity, and waning regional importation. The slaves from the Bight of Biafra and West-central Africa were imported in great numbers; however, the results suggest a deficit in expected maternal contribution from those regions.</p> <p>Conclusions: When considering the demographic pressures imposed by chattel slavery on Jamaica during the slave era, the results seem incongruous. Ethnolinguistic and ethnographic evidence, however, may explain the apparent non-random levels of genetic perseverance. The application of genetics may prove useful in answering difficult demographic questions left by historically voiceless groups.</p&gt

Performance Evaluation of Judgmental Directional Exchange Rate Predictions

Cataloged from PDF version of article.A procedure is proposed for examining different aspects of performance for judgemental directional probability predictions of exchange rate movements. In particular, a range of new predictive performance measures is identified to highlight specific expressions of strengths and weaknesses in judgemental directional forecasts. Proposed performance qualifiers extend the existing accuracy measures, enabling detailed comparisons of probability forecasts with ex-post empirical probabilities that are derived from changes in the logarithms of the series. This provides a multi-faceted evaluation that is straightforward for practitioners to implement, while affording the flexibility of being used in situations where the time intervals between the predictions have variable lengths. The proposed procedure is illustrated via an application to a set of directional probability exchange rate forecasts for the US Dollar/Swiss Franc from 23/7/96 to 7/12/99 and the findings are discussed. D 2005 International Institute of Forecasters. Published by Elsevier B.V. All rights reserved

Evaluating predictive performance of judgemental extrapolations from simulated currency series

Cataloged from PDF version of article.Judgemental forecasting of exchange rates is critical for ®nancial decision-making. Detailed investigations of the potential e ects of time-series characteristics on judgemental currency forecasts demand the use of simulated series where the form of the signal and probability distribution of noise are known. The accuracy measures Mean Absolute Error (MAE) and Mean Squared Error (MSE) are frequently applied quantities in assessing judgemental predictive performance on actual exchange rate data. This paper illustrates that, in applying these measures to simulated series with Normally distributed noise, it may be desirable to use their expected values after standardising the noise variance. A method of calculating the expected values for the MAE and MSE is set out, and an application to ®nancial experts' judgemental currency forecasts is presented. Ó 1999 Elsevier Science B.V. All rights reserved

An investigation of laboratory test methods for predicting the in-use leakage performance of urine-absorbing aids in nursing homes

The absorption before leakage method for measuring the absorption capacity of urine-absorbing aids was investigated. Along with the existing international standard (ISO 11948-1:1996, the Rothwell method), it was run on 12 experimental products whose in-use leakage performance was established by 55 incontinent nursing home residents. Methods were evaluated by considering their simplicity, their repeatability within - and their reproducibility between - six laboratories, and their correlation with in-use product performance. ISO 11948-1:1996 - which measures the absorption capacity of products under simple conditions - showed good repeatability and reproducibility, and reasonable correlation with in-use data. However, it proved blind to the effects of leg cuffs that conferred measurable benefits in real use. It should, therefore, be used with caution. The absorption before leakage method - which measures how much a product will hold before leakage when it is mounted on a manikin and standard aliquots of liquid are applied - is more complex and had poorer repeatability and reproducibility. However, it had stronger correlations with in-use data and successfully detected the benefits of leg cuffs on insert products. It is concluded that it holds potential as a new international standard to replace or complement ISO 11948-1:1996, and the necessary refinement work has been ongoing since the 2007 project described here. Two other laboratory methods were run opportunistically. A rewet method (Spanish national standard UNE 153601-2:2008) - for measuring the escape of fluid from a product under pressure - showed poor repeatability and reproducibility. Finally, an acquisition method was used to measure how quickly products absorbed two successive standard aliquots of liquid. It proved robust, showing good repeatability and reproducibility. Although measurements generally correlated well with in-use leakage performance, a direct causal link is unlikely. Products with high absorption capacity tend also to absorb quickly

The Effects of Substituting Glassware for Plasticware and the Use of an Ethanol Vector on Oocyte Maturation In Vitro

The intent of this study was to evaluate specific technical aspects of in vitro oocyte maturation (IVM), which included container material and solvent delivery vector. Oocytes were matured in oil-free, open-well systems contained in either plastic or glass dishes and compared to control oocytes matured in media droplets on plastic dishes overlaid with mineral oil. Open-well experiments were repeated with ethanol in a quantity sufficient for delivery of nonmiscible compounds. Cleavage rates were significantly decreased in the glassware system when compared to controls. The plasticware open-well system did not differ from either the controls or the glassware groups. Cleavage in glassware with ethanol was significantly lower than controls or plasticware with ethanol. Blastocyst rates were only decreased in the glassware-ethanol treatment when compared to plasticware-ethanol treatment. Cell counts and percentage of TUNEL-positive cells did not differ significantly. Unexpectedly, sex ratio was significantly decreased (34% male) from the expected value of 50% male in the glassware group with added ethanol. The current study demonstrates the sensitivity of IVM to subtle technical changes, resulting in significant developmental consequences

Fermat hypersurfaces and Subcanonical curves

We extend the classical Enriques-Petri Theorem to $s$-subcanonical projectively normal curves, proving that such a curve is $(s+2)$-gonal if and only if it is contained in a surface of minimal degree. Moreover, we show that any Fermat hypersurface of degree $s+2$ is apolar to an $s$-subcanonical $(s+2)$-gonal projectively normal curve, and vice versa.Comment: 18 pages; AMS-LaTe

Regina Lectures on Fat Points

These notes are a record of lectures given in the Workshop on Connections Between Algebra and Geometry at the University of Regina, May 29--June 1, 2012. The lectures were meant as an introduction to current research problems related to fat points for an audience that was not expected to have much background in commutative algebra or algebraic geometry (although sections 8 and 9 of these notes demand somewhat more background than earlier sections).Comment: 32 pages, 3 figure