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An oligonucleotide probe, designated VP5 and derived from the hemolysin gene, was developed to detect for the presence of Vibrio parahaemolyticus in shellfish. Tests on artificially contaminated oysters showed that the probe could detect V. parahaemolytucus at levels of about 10(super 6) colony forming units. DNA hybridization tests confirmed the probe's specificity to V. parahaemolyticus, although it did not hybridize to DNA of five V. parahaemolyticus isolates. These results demonstrate that VP5 may be used to directly identify V. parahaemolyticus in food samples.

Functional principal component analysis is one of the most commonly employed approaches in functional and longitudinal data analysis and we extend it to analyze functional/longitudinal data observed on a general d-dimensional domain. The computational issues emerging in the extension are fully addressed with our proposed solutions. The local linear smoothing technique is employed to perform estimation because of its capabilities of performing large-scale smoothing and of handling data with different sampling schemes (possibly on irregular domain) in addition to its nice theoretical properties. Besides taking the fast Fourier transform strategy in smoothing, the modern GPGPU (general-purpose computing on graphics processing units) architecture is applied to perform parallel computation to save computation time. To resolve the out-of-memory issue due to large-scale data, the random projection procedure is applied in the eigendecomposition step. We show that the proposed estimators can achieve the classical nonparametric rates for longitudinal data and the optimal convergence rates for functional data if the number of observations per sample is of the order $$(n/ \log n)^{d/4}$$ . Finally, the performance of our approach is demonstrated with simulation studies and the fine particulate matter (PM 2.5) data measured in Taiwan. [ABSTRACT FROM AUTHOR]

To survey the hygienic quality and freshness of fresh fish and shellfish, 533 specimens of fish and shellfish were collected from fishing piers, traditional markets and supermarkets (including warehouses) in northern Taiwan during the winter (January-February) and summer (July-August) seasons for hygienic quality and freshness examinations. The indicators included total bacterial count, fecal coliform, Escherichia coli, volatile basic nitrogen (VBN) and K value judged from ATP-related compounds. It was found that the hygienic quality and freshness of fish and shellfish decreased in summer, especially for clam and mussel. The ratio of unacceptable hygienic quality or freshness of fish and shellfish was the highest in fecal coliform, followed by E. coli and others. The fecal coliform count in products from the traditional markets was the highest, followed by those from supermarkets and fishing piers. Secondary contamination seems to be the most important problem for hygienic quality and freshness of fish and shellfish.