Generalizability theory.

Generalizability Theory (GT) provides a flexible, practical framework for examining the dependability of behavioral measurements. GT extends classical theory by (a) estimating the magnitude of multiple sources of measurement error, (b) modeling the use of a measurement for both norm-referenced and domain-referenced decisions, (c) providing reliability (generalizability) coefficients tailored to the proposed uses of the measurement, and (d) isolating major sources of error so that a cost-efficient measurement design can be built. Unfortunately, GT has not been readily accessible to psychological researchers. G theory's inaccessibility may explain why classical theory remains the preferred method for estimating reliability. The purpose of this article is to present GT and its wide applicability to a broad audience. Our intent is to demystify GT and provide a useful tool to psychological researchers and test developers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ursolic acid from Plantago major, a selective inhibitor of cyclooxygenase-2 catalyzed prostaglandin biosynthesis

A hexane extract of Plantago major was investigated by bioactivity-directed fractionation, using an in vitro cyclooxygenase-2 (COX-2) catalyzed prostaglandin biosynthesis inhibition assay, and resulted in the isolation of ursolic acid (1). This triterpenoid showed a significant COX-2 inhibitory effect, directly on the enzyme activity, with an IC50 value of 130 microM and a COX-2/COX-1 selectivity ratio of 0.6. The structural isomer oleanolic acid (2) was found to be less active than 1, with an IC50 value of 295 microM, but showed a similar selectivity ratio (0.8). Furthermore, no significant inhibition on COX-2 or COX-1 was observed by the triterpenoid, 18beta-glycyrrhetinic acid (3). The direct inhibitory effect of 1 and 2 on COX-2 catalyzed prostaglandin biosynthesis increased with preincubation, indicating a time-dependent inhibition, while the effect on COX-1 was found to be independent of preincubation time.     

Mycotoxins in edible tree nuts

Tree nuts (almonds, pistachios, and walnuts) are an exceptionally valuable crop, especially in California, with an aggregate value approaching $3.5 billion. Much of this economic value comes from overseas markets, with up to 60% of the crop being exported. The product can be contaminated with aflatoxins or ochratoxins, with the former being of special concern because of the strict regulatory levels (4 ppb total aflatoxins) applied by the European Community (EC). Natural, consumer-acceptable control methods are therefore required to conform to such limits. Research has shown that aflatoxin production is markedly decreased by the presence of natural antioxidants that occur in tree nuts, including hydrolysable tannins, flavonoids and phenolic acids. In vitro testing of individual compounds showed that the antiaflatoxigenic effect correlated with the structure and concentration of such compounds in individual nut varieties and species. This lead to the hypothesis that aflatoxin biosynthesis is stimulated by oxidative stress on the fungus and that compounds capable of relieving oxidative stress should therefore suppress or eliminate aflatoxin biosynthesis. Oxidative stress induced in A. flavus by addition of tert-butyl hydroperoxide to the media stimulated peak aflatoxin production and maintained high levels over time. However, aflatoxin formation was significantly inhibited by incorporation into the media of the antioxidant, tannic acid. Measures to increase natural products with antioxidant properties in tree nuts may thereby reduce or eliminate the ability of A. flavus to biosynthesize aflatoxins, thus ensuring levels at or below regulatory limits and maintaining export markets for U.S. tree nuts.     

Pre-Treatment of Platinum Resistant Ovarian Cancer Cells with an MMP-9/MMP-2 Inhibitor Prior to Cisplatin Enhances Cytotoxicity as Determined by High Content Screening

Platinum resistance is a major cause of treatment failure in ovarian cancer. We previously identified matrix metalloproteinase 9 (MMP-9) as a potential therapeutic target of chemoresistant disease. A2780cis (cisplatin-resistant) and A2780 (cisplatin-sensitive) ovarian carcinoma cell lines were used. The cytotoxic effect of MMP-9/MMP-2 inhibitor, (2R)-2-[(4-Biphenylsulfonyl) amino]-3 phenylpropionic acid (C21H19NO4S) alone or in combination with cisplatin was determined using high content screening. Protein expression was examined using immunohistochemistry and ELISA. Co-incubation of cisplatin and an MMP-9/MMP-2 inhibitor, (2R)-2-[(4-Biphenylsulfonyl) amino]-3 phenylpropionic acid (C21H19NO4S) resulted in significantly greater cytotoxicity as compared to either treatment alone in a cisplatin resistant MMP-9 overexpressing cell line; A2780cis. In addition, pre-incubating with MMP-9i prior to cisplatin further enhances the cytotoxic effect. No significant difference was observed in MMP-9 protein in tissue but a trend towards increased MMP-9 was observed in recurrent serum. We propose that MMP-9/MMP-2i may be utilized in the treatment of recurrent/chemoresistant ovarian cancers that overexpress MMP-9 mRNA but its role in vivo remains to be evaluated.     

Recent trends in environmentally friendly water-borne polyurethane coatings: A review

Environmentally friendly waterborne polyurethane (WPU) coatings are used extensively due to their low VOCs emission than solvent based PU coatings. Additionally, WPU coatings have low temperature flexibility, pH stability, water resistance, superior solvent resistance, outstanding weathering resistance and desirable chemical and mechanical properties. This review provides an overview on the recent developments of WPU coatings and their value added applications in the coatings and paint industry. UV-cured WPU coatings provide an important class of green and ecofriendly coatings with outstanding mechanical properties and rapid curing system. Hyper-branched polyurethanes (PUs) show interesting properties, such as high solubility, reactivity and good rheological behavior owing to multiple end groups, compact molecular structure and diminishing chain entanglement. Inherently, WPU coatings have reduced stiffness and mechanical strength that can be increased by the addition of nanoparticles, like Ag, Cu, TiO₂, SiO₂ and many more. Fire retardants, commonly phosphorous, are incorporated in the WPU structure to increase the flame retardancy of WPU coatings.     

Enhancement of Commercial Antifungal Agents by Kojic Acid

Natural compounds that pose no significant medical or environmental side effects are potential sources of antifungal agents, either in their nascent form or as structural backbones for more effective derivatives. Kojic acid (KA) is one such compound. It is a natural by-product of fungal fermentation commonly employed by food and cosmetic industries. We show that KA greatly lowers minimum inhibitory (MIC) or fungicidal (MFC) concentrations of commercial medicinal and agricultural antifungal agents, amphotericin B (AMB) and strobilurin, respectively, against pathogenic yeasts and filamentous fungi. Assays using two mitogen-activated protein kinase (MAPK) mutants, i.e., sakAΔ, mpkCΔ, of Aspergillus fumigatus, an agent for human invasive aspergillosis, with hydrogen peroxide (H₂O₂) or AMB indicate such chemosensitizing activity of KA is most conceivably through disruption of fungal antioxidation systems. KA could be developed as a chemosensitizer to enhance efficacy of certain conventional antifungal drugs or fungicides.     

An ethnographic exploration of perceptions of changes in dietary variety in the Kolli Hills,India

The Malayalis Tribe, a Scheduled Tribe of the Kolli Hills in southern India, has experienced a decrease in the variety of foods consumed in the past 20 years. It is important to understand these changes in dietary patterns to inform future interventions to improve dietary diversity. This study aimed to investigate the perceived factors and experiences from participants belonging to different age groups and genders that have affected changes in dietary variety in the Kolli Hills over the past 20 years. An ethnographic approach was used for the study. Data collection methods included semi-structured focus group discussions, informal individual interviews, and participant observations. Inductive thematic analysis was used to analyze themes related to the research questions. Results suggest that dietary diversity has declined and a smaller number of foods are consumed from grain products, fruits, vegetables and meat products. The main reasons for the decrease in dietary variety include an increased reliance on market systems (linked with an increase in cassava cash cropping) to obtain food and a lack of financial resources to purchase a variety of foods for consumption. Intergenerational changes in taste preferences influenced the types of foods consumed in the household. Drudgery associated with preparing traditional millets for consumption made it a less favorable choice in comparison to subsidized rice purchased through Fair Price Shops. The findings from this study are important to understand the changes in dietary patterns from the perspective of community members and will help inform future interventions to improve dietary diversity in the Kolli Hills.