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Bionic propulsion technology is revolutionizing underwater exploration by enabling underwater vehicles to navigate the oceans more efficiently. This research developed a scaled-down (10:1) experimental prototype of bionic manta-ray underwater vehicle, which has two degrees of freedom (2-DOF) pectoral fins: flapping and rotating. The impact of four different pectoral fin motion patterns (sinusoidal flapping and rotating, flapping frequency asymmetric, flapping amplitude offset, and rotating amplitude limitation) on the forward propulsion performance was investigated experimentally in a static water tunnel using a force/torque sensor and power analyzer. The results revealed that introducing asymmetry into the fin's flapping motion (asymmetric frequency or amplitude) significantly improved both average thrust and propulsive efficiency (the average thrust can be increased by more than 30%). Flapping with amplitude offset can effectively adjust its pitching moment without sacrificing much thrust. While the rotating motion of the pectoral fins contributes minimally to thrust generation compared to flapping, it plays an important role in enhancing both longitudinal stability and propulsive efficiency. Understanding the hydrodynamic performance of these various forward propulsion modes provides valuable insights for optimizing control strategies of bionic manta-ray underwater vehicles. • Four forward propulsion modes of the bioinspired manta ray underwater vehicles are considered. • Average thrust, power consumption, propulsion efficiency, and how thrust and lift vary within a single flapping cycle are investigated and discussed. • Asymmetric motion can improve both thrust and propulsion efficiency at low flapping frequencies. • The bionic pectoral fin exhibits superior propulsion efficiency within a suitable range of flapping frequency and angle of attack. [ABSTRACT FROM AUTHOR]

As the largest wood-based panel producing and exporting country, China has experienced sharp reductions in the growth rate of its wood-based panel exports because of pressure caused by exchange-rate fluctuation. These fluctuations were exacerbated by the global financial crisis. China's wood-based panel exporters need to adjust their pricing strategy to cope with the changes of international market conditions. Thus, it is necessary to investigate the relationship between exchange-rate fluctuation and the pricing behavior of China's wood-based panel exporters. To evaluate the impact of the exchange rate on China's wood-based panel export prices across multiple destinations, a pricing-to-market model incorporating panel data was used. The empirical results suggest that although complete exchange-rate pass-through exists widely in China's wood-based exports, China's fiberboard and plywood exporters tended to adopt different pricing strategies in the international wood-based panel market during the post-crisis era. China's fiberboard exporters often used the pricing-to-market model to determine prices in the main export destination countries, while China's plywood exporters tended to amplify the exchange-rate effects. This indicates that China's plywood exporters have stronger international market power than China's fiberboard exporters, partly because China's plywood exporters have more advantages in terms of skilled labor. [ABSTRACT FROM AUTHOR]

Cachexia affects approximately 50–80 % of advanced cancer patients, particularly those with gastric cancer (GC). Therefore, early detection of cachexia is essential to prevent its progression. Targeting the gut microbiota may be a promising approach for preventing and treating cachexia in patients with GC. Chemotherapy significantly reduced gut microbiota diversity in GC patients. Specifically, the abundance of bacterial genera such as Bacteroides , Streptococcus , and Prevotella was increased in the gut of patients postchemotherapy, which was closely associated with the development of cachexia. Serum metabolic analysis revealed a strong link between specific microbes and metabolite in patients with chemotherapy-induced GC cachexia. We further constructed a random forest model based on the top 6 genera in terms of abundance for the prediction of chemotherapy-related GC cachexia development; this model had an area under the receiver operating characteristic curve (AUC) of 93.5 % [95 % confidence interval (CI), 86.6 %-100 %], with a specificity and accuracy above 75 %. Additionally, we identified Enterotoxin Bacteroides fragilis (ETBF) as a key factor in chemotherapy-induced GC cachexia. In an in vivo GC model, the colonization of ETBF in the intestines of mice significantly accelerated the muscle and adipose tissue consumption induced by chemotherapy, resulting in cachexia symptoms. Furthermore, ETBF damaged the intestinal mucosal barrier by disrupting cell connections and attracting M1 macrophages, which advances GC cachexia. In conclusion, our findings indicate that gut microbiota imbalance is crucial in GC cachexia development, suggesting potential biomarkers for early diagnosis. Clinical trial registration: http://www.chictr.org.cn , Identification No: ChiCTR2200064547 [Display omitted] • Intestinal microbiota imbalance and metabolic disorders significantly contribute to cancer cachexia. • ETBF causes endotoxaemia by directly disrupting the intestinal mucosal barrier and indirectly releasing toxins. • ETBF promotes GC cachexia by recruiting intestinal macrophages to influence the intestinal immune microenvironment. • A random forest prediction model offers the possibility of predicting the potential clinical population of GC cachexia. [ABSTRACT FROM AUTHOR]

Chitosan microspheres (CsMs) that encapsulate salidroside (Sal) were prepared by the emulsion crosslinking method with naturally occurring genipin (Gp) and then examined for their in vitro release. Sal-loaded CsMs (Sal-CsMs) showed nearly spherical and smooth surfaces with internal voids. The particle size of Sal-CsMs ranged within 0.56-5.01 μm, and their encapsulation efficiency and loading capacity were beyond 77.58% and 23.29%, respectively. The stability of Sal improved after entrapment into the CsMs. The release rate of Sal from CsMs was initially rapid, followed by sustained release. The release behavior depended on the pH of the release medium. The main release mechanisms underlying the release procedure were anomalous behavior and Fickian diffusion. These results indicated that CsMs with a novel crosslinker of Gp was a potential carrier system for producing functional foods containing Sal. [ABSTRACT FROM AUTHOR]