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Simple Summary: Intermittent and chronic hypoxia are common and harmful to marine animals. The tiger puffer is a representative species of the family Tetraodontidae, which has only slit-like gill openings and is susceptible to hypoxia stress. Both intermittent and chronic hypoxia decrease the growth and visceral weight of tiger puffer but increase the feed conversion ratio and blood hemoglobin content. Chronic hypoxia but not intermittent hypoxia promoted protein synthesis and the glycolysis pathway. Intermittent hypoxia but not chronic hypoxia decreased lipid synthesis and monounsaturated fatty acids content but increased n-3 polyunsaturated fatty acids levels. These changes promoted the adaption of tiger puffer to intermittent and chronic hypoxia. Intermittent and chronic hypoxia are common stresses to marine fish, but the different responses of fish to intermittent and chronic hypoxia have not been well-known. In this study, tiger puffers were farmed in normoxia conditions (NO, 6.5 ± 0.5 mg/L), intermittent hypoxia (IH, 6.5 ± 0.5 mg/L in the day and 3.5 ± 0.5 mg/L in the night), or choric hypoxia (CH, 3.5 ± 0.5 mg/L) conditions for 4 weeks, after which the growth, nutrient metabolism and three hifα isoforms expression were measured. Both intermittent and chronic hypoxia decreased the fish growth and visceral weight but increased the feed conversion ratio and blood hemoglobin content. Chronic hypoxia but not intermittent hypoxia promoted protein synthesis and whole-fish protein content by activating mtor gene expression and promoted the glycolysis pathway by activating gene expression of hif1α and hif2α. Intermittent hypoxia but not chronic hypoxia decreased the hepatic lipid synthesis by inhibiting fasn and srebf1 gene expression. Meanwhile, intermittent hypoxia reduced the monounsaturated fatty acid content but increased the n-3 polyunsaturated fatty acids percentage. The results of this study clarified the adaptive mechanism of tiger puffer to intermittent and chronic hypoxia, which provides important information about mechanisms of hypoxia adaption in fish. [ABSTRACT FROM AUTHOR]

The polychaeta Neanthes japonica is a common by-product in mariculture ponds. It is rich in essential nutrients, but has not been well-explored. Therefore, this 56-day experiment investigated the effects of substituting N. japonica meal for dietary fishmeal on juvenile tiger puffer (15.49 ± 0.02 g, n = 450 fish). The control diet (CON) contained 40% fishmeal. Freeze-dried N. japonica meal (FNM) was supplemented into CON at the levels of 3% (FNM3), 6% (FNM6), and 9% (FNM9), replacing fishmeal. The fifth diet contained 6% oven-dried N. japonica meal (ONM6), replacing fishmeal. The results indicated that no significant difference was observed in growth, feed efficiency, and somatic index among all the treatment groups. The feed intake of the FNM6 group was significantly higher compared to CON. No significant difference was detected in fish proximate composition, as well as the fatty acid composition, amino acid composition, and muscle texture. The supplementation of N. japonica meal decreased the activities of intestinal lipase and α-amylase. The addition of freeze-dried N. japonica meal significantly up-regulated the expression of the intestinal amino-glycine transporter pat1. It was concluded that adding 9% N. japonica meal to the feed had no significant effect on the growth performance and body composition of juvenile tiger puffer. [ABSTRACT FROM AUTHOR]

Palm oil, with its higher production, lower prices, and higher levels of palmitic acid and oleic acid, may have great potential for use in the aquafeed industry. In this study, with an 8‐week feeding experiment, the efficacy of palm oil as a substitute for fish oil in tiger puffer feeds was comprehensively evaluated. The control diets (FO group) contained 8% marine fish oil as the main lipid source, while in the treatment diets, the added marine fish oil was replaced with palm oil at 25%, 50%, 75%, and 100%, respectively, which was named 25PO, 50PO, 75PO, and 100PO, respectively. Juvenile tiger puffers with an initial weight of 15.0 ± 0.04 g were used, with three replicate tanks of 30 juvenile fish tiger puffer for each dietary group. The fish oil replacement by palm oil did not have an adverse effect on fish growth and feeding, but the weight gain decreased by 17.3% in group PO100. Palm oil had no significant effects on fish proximate composition and muscle texture. The effects of dietary palm oil on muscle fatty acid composition were not significant, with DHA and EPA significantly lowered only in the 100PO group. In contrast, the changes in liver and intestinal fatty acid compositions in response to diets were more significant than those in the muscle. In the intestine, the replacement of more than 50% fish oil by palm oil significantly downregulated the gene expression associated with peroxisomal fatty acid β‐oxidation and triglyceride hydrolysis, while upregulated the expression of cholesterol biosynthetic genes. In the liver, the replacement of more than 75% fish oil also significantly upregulated the cholesterol synthesis. In conclusion, palm oil can replace 75% of added marine fish oil in tiger puffer diets and does not adversely affect the growth performance, feed utilization, muscle composition, and muscle texture. [ABSTRACT FROM AUTHOR]

In the information age, the amount of data is growing exponentially. However, different data sources are heterogeneous, which makes it inconvenient to share and multiplex data. With the rapid development of semantic network, ontology mapping is an effective method to solve this problem. The core of ontology mapping is ontology similarity calculation. Therefore, a calculation method based on graph convolution network was proposed. Firstly, ontologiesare modeled as a heterogeneous graph network, then the graph convolution network was used to learn the text embedding rules, which made ontologies were definedin global unified representation. Lastly, multisource data fusion was completed. The experimental results show that the accuracy of the proposed method is higher than other methods, and the accuracy of multi-source data fusion was effectively improved.

We have developed a dissolved oxygen (DO) method with differential equation (DE) correction. We measured the oxygen content in La-based and Y-based superconductors, and succeeded in measuring the oxygen content simply in one-third of the time required by the iodometric titration method. However, there was a problem with Bi-based superconductors where the measured oxygen content was smaller compared to the iodometric titration method. We hypothesized that not only O2 but also Cl2 gas is generated when dissolving Bi-based superconductors and developed a dissolved oxygen/chlorine (DO/Cl) method with DE correction. This method uses only a dissolved oxygen sensor and a dissolved chlorine sensor to measure the dissolved oxygen and dissolved chlorine content in Bi2Sr2−xLaxCuOy, allowing for the calculation of copper valence and oxygen content. The results from the DO/Cl method with DE correction show that the measured copper valence and oxygen content differ very little from those obtained using the iodometric titration method, with discrepancies within 0.016 and 0.008, respectively. Additionally, this method reduces the measurement time by one-third compared to the iodometric titration method. The results demonstrate that the DO/Cl method with DE correction can effectively measure the copper valence and oxygen content in cuprate superconductors, and using hydrochloric acid as the experimental solution is superior to sulfuric acid and nitric acid. [ABSTRACT FROM AUTHOR]

Micro-perforated panel (MPP) absorbers exhibit multiple resonance bands with increased bandwidth narrowing and shifting in higher frequencies, limiting their effectiveness. This study investigates the effects of narrowing and shifting in higher-order resonance bands of MPP absorbers. First, an acoustic impedance model for MPP absorbers is introduced, and the narrowing and shifting coefficients are defined and modeled to quantify these effects. It is observed that a larger ratio of acoustic resistance to acoustic mass is favorable for reducing the narrowing and shifting effects. Subsequently, the theoretical model is validated using a numerical model, and a parametric study is conducted to explore the influence of geometric parameters on the narrowing and shifting effects. The study reveals that decreasing aperture and panel thickness, while increasing perforation ratio and cavity depth, reduces the narrowing and shifting coefficients. Remarkably, ultra-micro-perforated panels (UMPPs) with an aperture below 0.1 mm and perforation constant below 0.0046, having relatively larger acoustic resistance and smaller acoustic mass, demonstrate near-zero band narrowing and shifting. Finally, UMPPs are fabricated using micro-electro-mechanical systems (MEMS) technology, and their normal absorption coefficients are measured. Results align with theoretical predictions, confirming UMPPs' ability to achieve zero narrowing and shifting compared to ordinary MPPs and verifying the study's findings. [ABSTRACT FROM AUTHOR]