Development of non-destructive methodology using ATR-FTIR with PCA to differentiate between historical Pacific barkcloth

Barkcloths, non-woven textiles originating from the Pacific Islands, form part of many museum collections and date back to the 18th and 19th centuries. The ability to determine different plant species which have been used for producing barkcloth is required by art historians to help understand the origin and use of the cloths and by conservators for whom the species type may have an impact on textile durability, deterioration and hence conservation. However, to date the development of a non-destructive, robust analytical technique has been elusive. This article describes the use of Fourier transform infrared spectroscopy with attenuated total reflection (ATR-FTIR) and principal component analysis (PCA) todifferentiation between historic barkcloths. Three distinct groups of historic cloths were identified using PCA of the FTIR region between 1200 and 1600 cm−1 where molecular vibrations associated with tannins and lignins are dominant. Analysis of contemporary cloths only identified Pipturus albidus cloth as different and highlighted the difficulties around producing a representative textile sample to mimic the historic cloths. While the methodology does not itself identify species, the use of historically well-provenanced samples allows cloths showing similarities to group together and is a significant aid to identification

Reducing Pesticide Movement to Surface Water

Pesticides (largely herbicides) can be detected in Iowa surface waters---but when found, are usually at very low concentrations (ppb). Concentrations and total herbicide losses to surface waters are often highest in the spring after chemical applications and heavy rains. Many management practices can be used to help minimize pesticides in Iowa waters. Farmers, dealers, and pesticide applicators may address the issue by focusing only on herbicide management. Other crop management tools are as important and should be considered before changing pest control strategies. The following checklist may be helpful for farm advisors reviewing options for reducing pesticides in surface waters

A Dictionary of the Novels of Charlotte Emily and Anne Bronte

A thesis presented to the English Department of Kansas University in partial fulfillment of the requirements for the degree of Master of Arts

A floristic survey of Benedict Prairie (Kenosha County, Wisconsin)

Benedict Prairie is a small railroad prairie that is owned and managed by the University of Wisconsin - Milwaukee Field Station. A floristic survey of the 2.5 ha site was conducted from 1988 to 1990. A total of 191 species, representing 51 families were identified, including Asclepias purpurascens and Parthenium integrifolium, which are protected in Wisconsin. This list was compared to two others compiled previously for the site. Compilation of all three lists brings the total number of species recorded from the site to 231, but reveals that a number of species appear to have been extirpated

Planting Pattern and Cultivar Effects on Flax Yields in Northwestern Iowa

In the United States, consumption of flaxseed and flaxseed oil is increasing both by direct consumption and as processed foods. Flaxseeds are high in alpha-linolenic acid, an omega-3 essential fatty acid, which is important for cardiovascular health. Whole-ground flaxseed in livestock diets can raise the level of these “healthy” fatty acids in meat and eggs. A new facility for organic flaxseed oil processing in Iowa has the potential to attract production to Iowa. Other grain buyers in the Upper Midwest are also increasing their purchase of flaxseed for animal feeds

Prediction-based classification for longitudinal biomarkers

Assessment of circulating CD4 count change over time in HIV-infected subjects on antiretroviral therapy (ART) is a central component of disease monitoring. The increasing number of HIV-infected subjects starting therapy and the limited capacity to support CD4 count testing within resource-limited settings have fueled interest in identifying correlates of CD4 count change such as total lymphocyte count, among others. The application of modeling techniques will be essential to this endeavor due to the typically nonlinear CD4 trajectory over time and the multiple input variables necessary for capturing CD4 variability. We propose a prediction-based classification approach that involves first stage modeling and subsequent classification based on clinically meaningful thresholds. This approach draws on existing analytical methods described in the receiver operating characteristic curve literature while presenting an extension for handling a continuous outcome. Application of this method to an independent test sample results in greater than 98% positive predictive value for CD4 count change. The prediction algorithm is derived based on a cohort of $n=270$ HIV-1 infected individuals from the Royal Free Hospital, London who were followed for up to three years from initiation of ART. A test sample comprised of $n=72$ individuals from Philadelphia and followed for a similar length of time is used for validation. Results suggest that this approach may be a useful tool for prioritizing limited laboratory resources for CD4 testing after subjects start antiretroviral therapy.Comment: Published in at http://dx.doi.org/10.1214/10-AOAS326 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Weed Management Strategies for Organic Flax, 2005–2006

Demand for certified organic flax has increased due to a rise in human consumption of food products rich in omega-3 oil and due to the recent construction of a certified organic oilseed expelling facility in Cherokee, IA. Challenges exist to raising organic flax in the upper Midwest due to competition from weeds and limited information about weed management strategies for organic farmers. Weeds can reduce flax yield and re-populate the soil seed bank, increasing weed pressure in the future. In 2005 and 2006, research was conducted to assess: 1) which weed management strategies can best control weeds in flax, and 2) how do weeds affect flax grain yield