Effects of cooking on anthocyanin concentration and bioactive antioxidant capacity in glutinous and non-glutinous purple rice

Purple rice is a source of bioactive antioxidants for rice consumers. Loss of the major antioxidant compounds after a range of cooking processes was evaluated by measuring the change in anthocyanin concentration (ATC) and antioxidant capacity (DPPH activity) of four non-glutinous and four glutinous genotypes. However, soaking in water prior to cooking generally decreased ATC and DPPH activity more in non-glutinous than in glutinous genotypes. Wet cooking (WC) and soaking before wet cooking (S-WC) led to almost all the ATC and DPPH activity being lost with only slight variation between genotypes. In the glutinous genotype PES, which had the highest raw rice ATC, the highest ATC remained when cooked by the WC method. By contrast, almost no ATC remained after WC and S-WC in the low ATC genotypes such as KDK. Overall, the loss of ATC on cooking was greater in non-glutinous than glutinous genotypes for both WC and S-WC, but the reverse occurred for DPPH activity. Wet cooking using electric rice cooker retained higher ATC than the pressure cooking. Thus, for genotypes with high ATC and antioxidant capacity, the selection of cooking method is critical for retaining and stabilizing rice quality

Time-varying Learning and Content Analytics via Sparse Factor Analysis

We propose SPARFA-Trace, a new machine learning-based framework for time-varying learning and content analytics for education applications. We develop a novel message passing-based, blind, approximate Kalman filter for sparse factor analysis (SPARFA), that jointly (i) traces learner concept knowledge over time, (ii) analyzes learner concept knowledge state transitions (induced by interacting with learning resources, such as textbook sections, lecture videos, etc, or the forgetting effect), and (iii) estimates the content organization and intrinsic difficulty of the assessment questions. These quantities are estimated solely from binary-valued (correct/incorrect) graded learner response data and a summary of the specific actions each learner performs (e.g., answering a question or studying a learning resource) at each time instance. Experimental results on two online course datasets demonstrate that SPARFA-Trace is capable of tracing each learner's concept knowledge evolution over time, as well as analyzing the quality and content organization of learning resources, the question-concept associations, and the question intrinsic difficulties. Moreover, we show that SPARFA-Trace achieves comparable or better performance in predicting unobserved learner responses than existing collaborative filtering and knowledge tracing approaches for personalized education

The value of express delivery services for cross-border e-commerce in European Union markets

Further growth of cross-border e-commerce in the European Union markets requires improved express delivery services. The framework presented in this paper identifies relevant contextual factors that affect express delivery adoption rates in European cross-border e-commerce. This framework leads to a set of hypotheses, both on the effects of express deliveries on financial performance indicators (order incidence, order size, and repurchase rate) and on the factors that drive demand for express deliveries (consumer income, logistic costs, and lead-time benefits). A case study provides empirical tests of the hypotheses, using data on about forty thousand sales transactions from a consumer electronics manufacturer’s cross-border online shop. The findings are that express delivery has positive effects on financial performance, as it leads to higher order incidence, larger order size, and higher repurchase rates in cross-border transactions. Demand for express delivery services increases with higher income, larger lead-time benefits, and lower logistic costs. Managers can employ the presented framework to formulate and analyse their own targets for performance and express delivery services

Freeze fracture study of airway epithelium from patients with primary ciliary dyskinesia

Methods: The nasal epithelium of three patients with PCD was freeze fractured and replicated with platinum and carbon shadowing. The resultant preparations were examined by transmission electron microscopy and the ciliary necklaces were compared with similar preparations of nasal biopsy specimens from normal healthy subjects

Easy and rapid detection of iron in rice grain

In this study, we show how a preliminary determination of grain Fe in rice may be made with reaction to Perls’ Prussian blue, a stain for Fe (III). Differential localization of Fe in grain parts was indicated by the intensity of reaction of tissue Fe to the dye. The blue colour reaction was most intense in the embryo, weak in the aleurone layer of the pericarp and invisible in the endosperm. The staining intensity also varied with the region of the embryo, generally being strongest in the scutellum, intermediate in the coleorhiza and weakest in the coleoptile. Variation in the reaction to Perls’ Prussian blue was observed among eleven rice genotypes with varying grain Fe contents. The intensity of the blue colour reaction in the embryo of different rice genotypes was indicative of their grain Fe contents for both brown and white (polished) rice. Those with high grain Fe, >14 mg Fe kg-1, were clearly distinguishable from those with <10 mg Fe kg-1 with Perls’ Prussian blue. We suggest that this simple staining procedure may be used to quickly screen for high Fe contents in large germplasms containing hundreds of rice entries, using reactions in genotypes with known grain contents as standards