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There have been few high‐resolution investigations covering the last glacial and Holocene from Sichuan, Yunnan, or south Asia area in the south‐west monsoon domain region. High‐resolution analyses of lake sediments retrieved from Qionghai Lake, Sichuan Province, were conducted using a combination of variables including total organic carbon (TOC) and total nitrogen (TN) concentration, low frequency magnetic susceptibility (χLF), particle size, carbonate content, and δ13C value of organic matter (δ13Corg), to provide a new perspective on the detailed paleoclimate history of south‐west China spanning the past 30 cal ka BP. Our findings suggest that organic matter in the Qionghai Lake was mainly derived from microorganisms, aquatic macrophytes, and terrestrial C3 plants. From 29.1 to 23.2 cal ka BP, low carbonate contents, high median grain size (Md values), and χLF values indicated a warm and wet climate. During the period 23.2 to 15.4 cal ka BP, low χLF, Md values, and high carbonate contents suggested a decrease in temperature and humidity. The cold and dry Last Glacial Maximum (LGM) and Heinrich 1 event (H1) were captured between 21.6 and 19.4 cal ka BP and 17.6 and 15.8 cal ka BP, respectively. During the interval 15.4 to 9.7 cal ka BP, low level of χLF values and Md values, together with relatively high carbonates, demonstrated that a dry climate prevailed in this period. Since 9.7 cal ka BP, the climate was warm and humid in the early to mid‐Holocene and shifted towards cold and dry condition in the late Holocene. A cold and dry period at 8.5 to 8.1 cal ka BP and warm and wet interval at 6.6 to 4.6 cal ka BP were identified, corresponding to the 8.2‐ka cold event and Holocene climatic optimum (HCO), respectively. These climate changes may reflect variations of the intensity of the south‐west summer monsoon, primarily in response to the Northern Hemisphere solar insolation on a millennial scale induced by orbital forcing. The position of the Intertropical Convergence Zone (ITCZ) may add a complementary effect on the evolution of the monsoon strength in the Holocene. [ABSTRACT FROM AUTHOR]

Tiger puffer fish (Takifugu rubripes)is one of the most economically valuable aquaculture species in Asia. However, farming tiger puffer fish at the juvenile stage has been greatly restrained by cannibalization caused by inappropriate feeding regimes, resulting in very high mortality and great economic loss, particularly in intensive recirculating aquaculture systems. Therefore, the feeding strategy should adapt to fish appetite, nutrition requirements and welfare in intensive aquaculture. A 60-day feeding experiment was conducted to evaluate the effects of feeding frequency on the overall health of juvenile tiger puffer fish. Fish were randomly assigned to four groups with different feeding frequencies using the same ration size per feeding. P1: two daily meals; P2: four daily meals; P3: six daily meals; P4: continuous diurnal feeding using a belt feeder. Fish in the P2 group exhibited optimal values for growth, including final weight, weight gain rate, specific growth rate, feed efficiency, and survival (P < 0.05), followed by those in the P3 group. The crude lipid content increased significantly with increasing feeding frequency (P < 0.05), indicating that high frequency feeding could accumulate higher body fat content. The apparent digestibility coefficients of dry matter, protein, and lipid were significantly lower for fish in the P4 group than for those in the other groups (P < 0.05). The total cholesterol, triglyceride, and glucose levels increased significantly with increasing feeding frequency (P < 0.05), indicating that high frequency feeding leads to excessive accumulation of dietary carbohydrates and lipids in juvenile tiger puffer fish. Fish in the P1 and P4 groups exhibited relatively higher antioxidant enzyme activities (P < 0.05), which suggested that low and high feeding frequencies cause oxidative stress in juvenile tiger puffer fish. A comparison of non-linear model parameters revealed that an exponential model best described the gastric evacuation rate of juvenile tiger puffer fish, with approximately half the meal passed within 3 h, which further confirmed that feeding intervals in four times/day may more closely align with the digestive physiological characteristics of juvenile tiger puffer fish. Overall, these results indicate that the best growth performance and physiological indicators can be achieved when fed at 4 times/day. • High frequency feeding causes carbohydrate and lipid accumulation in juvenile tiger puffer fish. • Low and high feeding frequencies had adverse effects for juvenile tiger puffer fish. • Variation in feeding frequency had no effect on GER, and approximately 50% of a single meal was passed within 3 h. • Optimal feeding frequency for cultured juvenile tiger puffer fish is four meals/day. [ABSTRACT FROM AUTHOR]

• Both S-muscone and R-muscone were acutely toxic to zebrafish embryonic heart. • Cardiotoxicity is partly related to increased Myh6 and Myh7 expression. • Muscone toxicity is related to thyroid hormone dysregulation. • R-muscone showed higher toxicity than S-muscone. Musk compounds are often used as to treat heart-related diseases and are widely used in Asia. Muscone is one of the most important physiologically active compounds of natural musk. Muscone is a chiral compound and can be further classified into S-muscone and R-muscone and both are present in synthetic musk. While these two chiral isomers have significant differences in odor properties, their difference in toxicity is still unknown. This study used zebrafish as an animal model to compare cardiac toxicities of S-muscone and R-muscone. Results showed that both compounds were acutely toxic to zebrafish embryos causing mortality, decreased hatching rate, pericardial edema, and decreased heart beat rate. These toxicities were modulated through increased Myh6 and Myh7 mRNA expression, and decreased thyroid genes (Trh, Thrβ, and Dio3) expression. R-muscone caused higher toxicity than S-muscone at the same concentration. For safety, the chiral isomer composition of synthetic muscone should be carefully regulated in the future. [ABSTRACT FROM AUTHOR]