Abstract Freezing technology is currently an important preservation method for aquatic products. However, during the long-term freezing process proteins, which are the main components of muscle tissue, are inevitably exposed to an environment containing oxidative stress inducing changes in muscle protein structure. It leads to irreversible physical and chemical changes causing deterioration in the quality of aquatic products and reducing their nutritional value. Therefore, it is necessary clarify in depth to control oxidative damage of muscle during freezing and storage to gain more insight into the mechanisms of freezing-induced protein oxidation. The mechanism of protein oxidation in fish freezing, the effect of protein oxidation on fish quality, and the current regulatory methods for delaying protein oxidation were summarized in this paper review. The purpose is to provide a new research direction for the research and application of quality control in the process of fish frozen storage.

Abstract Fresh aquatic products have high nutritional value, but they are easily susceptible to spoilage. Freezing as an effective preservation method could better retain the quality and safety of aquatic products. However, mechanical damage caused by ice crystals and the oxidation of proteins and lipids would inevitably bring about a reduction in the quality of the frozen product during freezing and preservation. This work summarized the important factors that affected the quality of frozen aquatic products, revealed the mechanism of deterioration of frozen aquatic products on the quality through sensory evaluation and changes in physiochemical indicators. In the context of high-quality development, some improvements in frozen fish preservation were proposed to provide theoretical basis and solutions to improve the quality and efficiency of fish processing.

ABSTRACT Low light levels during rice (Oryza sativa L.) growing seasons may lead to significant reductions in grain yield and quality. The effect of shading stress on remobilization of nonstructural carbohydrates (NSC) from the stem plus sheath (SPS) to the grain, a process crucial to rice grain formation, was investigated. Field shading experiments were conducted in Hanyuan and Wenjiang, China, using two rice varieties (Huanghuazhan and Guichao II) subjected to shading stress after heading. Stored NSC of 60.00-159.15 g m-2 were remobilized from SPS after heading, contributing 9.63%-23.63% to grain dry weight at maturity. Shading stress resulted in the 23.99%-50.30% and 31.65%-61.33% reduction in NSC content of SPS at 20 d after heading (DAH20) and maturity stages, respectively. This contributed to the 13.80%-89.00% increase in the remobilization of stored NSC from SPS to the grain (RASN) and 15.86%-73.30% increase in remobilization percentage of removed NSC from SPS to the grain (RPRN). The effect of shading stress on remobilization differed between sites and varieties. Owing to a greater sink capacity, shading stress led to a higher RASN and RPRN from heading to DAH20 for ‘Huanghuazhan’ in Hanyuan. To compensate for photosynthate deficiency under shading stress, rice is adapted to remobilize stored NSC during early grain filling stages. Consequently, grain yield loss caused by shading could be reduced by increasing the SPS remobilization ability (especially in low light areas). Increasing NSC accumulation in SPS before heading for later remobilization may be a feasible way to alleviate rice yield loss under adverse light conditions.

Induced pluripotent stem cells (iPSCs) obtained by the ectopic expression of defined transcription factors have tremendous promise and therapeutic potential for regenerative medicine. Many studies have highlighted important differences between iPSCs and embryonic stem cells (ESCs). In this work, we used meta-analysis to compare the global transcriptional profiles of human iPSCs from various cellular origins and induced by different methods. The induction strategy affected the quality of iPSCs in terms of transcriptional signatures. The iPSCs generated by non-integrating methods were closer to ESCs in terms of transcriptional distance than iPSCs generated by integrating methods. Several pathways that could be potentially useful for studying the molecular mechanisms underlying transcription factor-mediated reprogramming leading to pluripotency were also identified. These pathways were mostly associated with the maintenance of ESC pluripotency and cancer regulation. Numerous genes that are up-regulated during the induction of reprogramming also have an important role in the success of human preimplantation embryonic development. Our results indicate that hiPSCs maintain their pluripotency through mechanisms similar to those of hESCs.