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The circular aquaculture model of largemouth bass pond engineering has the characteristics of high yield and efficiency, but it is prone to stress caused by flow velocity and density, which affects the yield of largemouth bass (Micropterus salmoides). γ‐Aminobutyric acid (GABA) is believed to have the effect of improving growth and stress tolerance. We divided the largemouth bass into three groups: a control group, a flow rate and density combined stress group, and a combined stress feed supplemented with GABA (0.9%) group, and conducted a 60‐day aquaculture experiment. The results showed that the final weight, weight gain rate (WGR), specific growth rate (SGR), and feed efficiency (FE) of largemouth bass significantly decreased in the combined stress group (P < 0.05). The serum aspartate aminotransferase (AST), alanine transaminase (ALT) activity, and glucose (GLU), malondialdehyde (MDA) level of largemouth bass significantly higher than the control group, and the serum lysozyme (LZM) activity and total antioxidant capacity (T‐AOC) were significantly lower than the control group (P < 0.05). After adding GABA, the final weight, WGR, SGR, and FE decreased, and the serum GLU levels, AST, ALT activity, and MDA levels were downregulated, and the serum LZM activity and T‐AOC of largemouth bass were upregulated. But most of the above are still at the level of the control group. Under combined stress, the messenger ribonucleic acid (mRNA) expression levels of growth hormone (GH), insulin‐like growth factor‐Ⅰ (IGF‐I), B‐cell lymphoma‐2 (Blc2), nuclear transcription factor E2‐related factor 2 (Nrf2), catalase (CAT), and superoxide dismutase (SOD) genes were significantly reduced (P < 0.05), while the mRNA expression levels of heat stress protein 70 (HSP70), heat stress protein 90 (HSP90), nuclear factor kappa‐B (NF‐κB), interleukin‐1β (IL‐1β), Bax and keap1 genes were significantly increased (P < 0.05). After the exogenous addition of GABA, all the above genes have a certain degree of callback, but GH, HSP70, HSP90, IL‐1β, Bax, Nrf2, CAT, and SOD have not yet reached the level of the control group. These results indicate that adding GABA to feed can alleviate the adverse effects of combined stress of flow rate and density to a certain extent and provide insights for solving the problems in the circular aquaculture model of largemouth bass. [ABSTRACT FROM AUTHOR]

The COVID-19 outbreak led to widespread school closures and the shift to remote teaching, potentially resulting in lasting negative impacts on teachers' psychological well-being due to increased workloads and a perceived lack of administrative support. Despite the significance of these challenges, few studies have delved into the long-term effects of perceived instructional leadership on teachers' psychological health. To bridge this research gap, we utilized longitudinal data from 927 primary and secondary school teachers surveyed in two phases: Time 1 in mid-November 2021 and Time 2 in early January 2022. Using hierarchical linear modeling (HLM), our findings revealed that perceptions of instructional leadership, especially the "perceived school neglect of teaching autonomy" at Time 1 were positively correlated with burnout levels at Time 2. Additionally, burnout at Time 2 was positively associated with psychological distress and acted as a mediator between the "perceived school neglect of teaching autonomy" and psychological distress. In light of these findings, we recommend that schools prioritize teachers' teaching autonomy and take proactive measures to mitigate burnout and psychological distress, aiming for the sustainable well-being of both teachers and students in the post-pandemic era. [ABSTRACT FROM AUTHOR]

Three undescribed cassane-type diterpenoids (CAs), caesalpulcherrins K-M (1–3), together with three known ones (4–6) were isolated from the aerial parts of Caesalpinia pulcherrima (L.) Sw (Fabaceae). Their structures were elucidated via analysis of NMR (1 D and 2 D) and HRESIMS data. The character for caesalpulcherrin K possessing the olefin bond at C-11 and C-12 in its cassane skeleton was observed, which belonged to a small group among more than 450 CAs. That is, only fifteen derivatives have been reported up to now, to our knowledge. Biological evaluation revealed that compounds 1–6 exhibited moderate anti-inflammatory activity, with an IC50 value from 6.04 ± 0.34 to 8.92 ± 0.65 μM. Furthermore, compounds 5 and 6 exhibited significant α-glucosidase inhibitory activity at 10 μM. [ABSTRACT FROM AUTHOR]

Micropterus salmonides, Channa argus and Siniperca chuatsi, as carnivorous fish, were mostly fed with fresh feed and fresh bait in the traditional breeding process. In recent years, with the depth of research on nutritional requirement and feeding strategies, they has begun to culture with artificial compound feed, especially protein requirements. The paper summarizes the current research advances on protein nutritional requirements of Micropterus salmonides, Channa argus and Siniperca chuatsiat home and abroad, aiming to provide reference basis for accurate protein nutrition research. [ABSTRACT FROM AUTHOR]

Lipid content of a diet is very susceptible to oxidation, which has many negative effects on farmed animals. Therefore, this study studied the protective effect of L‐carnitine (LC) on fish body stimulated by oxidized fish oil (OFO) from lipid metabolism. Lipid content of the diet was replaced by OFO in 0, 100 and 400 meq/kg. L‐carnitine was added to the diet in two levels, 500 and 1,000 mg/kg, giving a total of seven experimental diets. A total of 735 healthy Rhynchocypris lagowski Dybowski with an initial weight of 4.48 ± 0.14 g after 2‐week adaptation randomly divided into 15 glass aquariums. Fish were fed satiated three times daily. After 8 weeks, biometry was done to evaluate growth performance, and hepatopancreas and muscle samples were taken for biochemical analysis. The result showed that feeding with OFO had negative growth. However, in fish received both OFO and LC, growth indices improved slightly (p >.05). Feeding with OFO and LC, the content of EPA, DHA and PUFA in the muscle of R. lagowski was significantly higher than that in the control group (p <.05), which reached the maximum value in the OFO100 + LC500 group. The content of SFA, MUFA, ∑n‐6 and PUFA in hepatopancreas increased significantly (p <.05), and the content of SFA reached the maximum in OFO100 + LC500 group. Feeding with OFO increased hepatopancreas total cholesterol, triacylglycerol, HDL/LDL ratio, FAS and ACCα that involved in lipid synthesis enzymes, while reduced HL and HSLα enzyme activity and gene expression that associated with lipid decomposition. Dietary LC moderated the effects of OFO on lipid metabolism. According to the result of the present study, it can be argued that feeding of R. lagowski with OFO has negative effects on growth performance and lipid metabolism, whereas LC dosages used in this study have increased the oxidation rate of fatty acids in the hepatopancreas of R. lagowski and improved the accumulation of fat in hepatopancreas cells induced by oxidized fish oil. [ABSTRACT FROM AUTHOR]