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'Cod'-related species are among the most appreciated marine fish resources around the world, but are also prone to species mislabelling. In the present study, a total of 76 frozen, dried, and surimi-based fish products, sold as 'Cod' (59 products), 'Atlantic authentic Cod' (11 products), and 'Authentic Cod' (6 products), were collected in China. A species-specific LAMP (loop-mediated isothermal amplification) method was used to screen for the presence of Atlantic cod (Gadus morhua), Pacific cod (G. macrocephalus), Alaska pollock (G. chalcogrammus), Southern hake (Merluccius australis), which was cross-confirmed using real-time PCR and DNA sequencing methods. The results highlighted the greatest species diversity for 'Cod' products, and the identified species were from nine different families. It appears that the practice of assigning a specific type or category of species to the common name 'Cod' has not been widely advocated, and the misuse of this ambiguous common name has been a common practice for species adulteration, negatively impacting consumers' rights and marine conservation. To rebuild consumers' confidence, retail fish suppliers have differentiated their products by adding specific qualifiers in front of the common name 'Cod' on the label, such as 'Authentic cod' and 'Atlantic authentic cod'. The endeavour is highly meaningful, since Gadus morhua was identified as the species for a significant majority of 'Atlantic authentic cod' and 'Authentic cod' products (64.7%, 11/17), with the remaining six products identified as Alaskan pollock (G. chalcogrammus), Pacific cod (G. macrocephalus) and North Pacific hake (Merluccius productus). Despite the positive effort to reverse species mislabelling from retail on-line fish suppliers, a standardized fish nomenclature stipulated by the responsible authorities remains crucial for enhancing transparency and continuing to reduce species mislabelling. [ABSTRACT FROM AUTHOR]

Admission decisions frequently rely on multiple assessments. As a consequence, it is important to explore rational approaches to combine the information from different educational tests. For example, U.S. graduate schools usually receive both TOEFL iBT® scores and GRE® General scores of foreign applicants for admission; however, little guidance has been given to combine information from these two assessments, even though the relationships between such sections as GRE Verbal and TOEFL iBT Reading are obvious. In this study, principles are provided to explore the extent to which different assessments complement one another and are distinguishable. Augmentation approaches developed for individual tests are applied to provide an accurate evaluation of combined assessments. Because augmentation methods require estimates of measurement error and internal reliability data are unavailable, required estimates of measurement error are obtained from repeaters, examinees who took the same test more than once. Because repeaters are not representative of all examinees in typical assessments, minimum discriminant information adjustment techniques are applied to the available sample of repeaters to treat the effect of selection bias. To illustrate methodology, combining information from TOEFL iBT scores and GRE General scores is examined. Analysis suggests that information from the GRE General and TOEFL iBT assessments is complementary but not redundant, indicating that the two tests measure related but somewhat different constructs. The proposed methodology can be readily applied to other situations where multiple assessments are needed.

BACKGROUND: Species adulteration has been widely revealed around the world, and the possible reasons include declining stocks in most source areas of the world, poor transparency in the global supply chain, and difficulty in distinguishing the features of processed products. The present work selected Atlantic cod (Gadus morhua) as a case study, and developed a novel loop‐mediated isothermal amplification (LAMP) assay for Atlantic cod authentication, where a self‐quenched primer and a newly designed reaction vessel were used to realize the endpoint visual detection of the target‐specific products. RESULTS: A novel LAMP primer set was designed for Atlantic cod, and the inner primer BIP was selected to label the self‐quenched fluorogenic element. The fluorophore's dequenching only occurred along with LAMP elongation for the target species. No fluorescence could be observed with both single‐stranded DNA and partially complementary dsDNA of the non‐target species. With the novel reaction vessel, both amplification as well as detection were operated in an enclosed device, and visual differentiation of Atlantic cod, negative control, and false positive generated from primer dimers was achieved. The novel assay has proved its specificity and applicability, and could detect as little as 1 pg of Atlantic cod DNA. Moreover, Atlantic cod adulteration as low as 10% could be detected in haddock (Melanogrammus aeglefinus), and no cross‐reactivity was observed. CONCLUSION: The established assay could be a useful tool to detect mislabeling incidents involving Atlantic cod considering the advantages of speed, simplicity and accuracy. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Aflatoxin B1 (AFB1) has been considered as a prevailing natural carcinogenic mycotoxin in various food and feedstuff products, posing serious endangers to human health. The quantitative and selective detection of AFB1 was significantly essential for food safety control. Results: We developed a label‐free fluorescent aptasensor using a target‐binding aptamer probe as the rolling circle amplification (RCA) primer for AFB1 detection. In the presence of AFB1, the probe preferentially combined with AFB1 rather than binding to the circular template, inhibiting the initiation of RCA process. The detection limit of the proposed method was as low as 6.6 nM, and the linear dynamic response range was four orders of magnitude wide. Besides, it revealed excellent specificity for AFB1 and high‐quality detection performance in food samples. Conclusion: The presented detection method was simple, rapid, and economical, which indicated a promising application in food safety monitoring. [ABSTRACT FROM AUTHOR]

Background: Aflatoxin B1 (AFB1) has been considered as a prevailing natural carcinogenic mycotoxin in various food and feedstuff products, posing serious endangers to human health. The quantitative and selective detection of AFB1 was significantly essential for food safety control. Results: We developed a label‐free fluorescent aptasensor using a target‐binding aptamer probe as the rolling circle amplification (RCA) primer for AFB1 detection. In the presence of AFB1, the probe preferentially combined with AFB1 rather than binding to the circular template, inhibiting the initiation of RCA process. The detection limit of the proposed method was as low as 6.6 nM, and the linear dynamic response range was four orders of magnitude wide. Besides, it revealed excellent specificity for AFB1 and high‐quality detection performance in food samples. Conclusion: The presented detection method was simple, rapid, and economical, which indicated a promising application in food safety monitoring. [ABSTRACT FROM AUTHOR]