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Simple Summary: The largemouth bass Micropterus salmoides is known for its rapid development, delectable flavor, robust disease resistance, and significant economic and nutritional value. It is widely cultivated and has emerged as a crucial aquatic food source in China. However, as the proportion of aquaculture continues to grow, the farming of largemouth bass is faced with various pathogenic microorganisms that cause a high mortality rate during production. Emodin, isolated from Polygonum cuspidatum, Polygonum multiflorum, and Rheum palmatum, has shown an extensive spectrum of pharmacological activities, and has been deemed to be a natural feed additive that can be used to enhance growth performance, antibacterial activity, and antioxidant capacity, as well as innate immunity, in several aquatic studies. The results of the present study suggest that emodin could improve non-specific immunity and resistance to pathogens in juvenile largemouth bass. Our findings also make an important contribution to the development of emodin as a natural feed additive to prevent diseases in the field of aquaculture in the near future. The experiment was aimed at examining the influence of adding emodin to feeds on the growth performance, liver immunity, and resistance against Aeromonas veronii infection among juvenile largemouth basses and other potential mechanisms. A total of 540 fish (45 ± 0.3 g) were randomly divided into 6 diets, including EM-0, EM-250, EM-500, EM-1000, EM-2000, and EM-4000 diets, in which 0, 250, 500, 1000, 2000, and 4000 mg kg−1 emodin was added. Following a 60-day feeding test, it demonstrated that the feed conversion ratio (FCR) of juveniles within the EM-500 and EM-1000 groups remarkably exceeded that of the EM-0 group. Subsequently, unlike those in EM-0 group, the fish in the EM-1000 group showed heightened hepatocyte count, induced hepatic lipolysis-associated expression of peroxisome proliferators-activated receptor α (PPARα) and acyl-coenzyme an oxidase (ACO), and reduced the hepatic triglyceride (TG) levels. Additionally, EM-1000 could up-regulate the expressions of nuclear factor erythroid 2-associated factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in livers compared with controls and boost antioxidant enzymes activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), along with a lower content of reactive oxygen species (ROS) and malondialdehyde (MDA). Meanwhile, the EM-1000 group increased anti-inflammatory cytokines of interleukin-10 (IL-10) while suppressing the interleukin-8 (IL-8) expression of pro-inflammatory cytokines in livers by contrast to controls. In the end, juvenile largemouth bass in the EM-1000 group showed a comparatively highest survival rate, whereas fish in the EM-2000 and EM-4000 groups exhibited a little higher mortality than that of the EM-0 group. To sum up, our study exposed that supplementing emodin with 1000 mg kg−1 in diet could enhance the hepatic antioxidant status and unspecific immunity to reinforce the protective effect on disease resistance, resulting in improving the growth performance in juvenile largemouth bass. [ABSTRACT FROM AUTHOR]

The effects of starvation and refeeding on the gut condition of juvenile largemouth bass (Micropterus salmoides) remain unclear. Therefore, our research aimed to explore these effects. Amylase and lipase activities were remarkably decreased in the starvation (ST) group, yet prominently increased in the refeeding (RE) group (p < 0.05). In addition to the malondialdehyde (MDA) level, catalase (CAT) and superoxide dismutase (SOD) activities were significantly upregulated in the ST group (p < 0.05) in marked contrast to those in the controls; however, the RE group showed no substantial variations in CAT and SOD activities or the MDA level (p > 0.05). During starvation, the expression of Nrf2-Keap1 pathway-associated genes was significantly upregulated (p < 0.05). The comparative levels of TNF-α, IL-1β, and IL-15 were highly increased, with the levels of TGF-β1 and IL-10 apparently downregulated in the ST group; in contrast, these levels were restored to their original values in the RE group (p < 0.05). In contrast to the controls, the ST group showed significantly lower height and width of the villi, muscle thickness, and crypt depth and a higher goblet cell number; however, these values were recovered to some extent in the RE group (p < 0.05). The dominant bacterial phyla in the intestines of both groups were Proteobacteria, Firmicutes, Bacteroidetes, Acidobacteria, and Actinobacteria, with marked inter-group differences in the genera Serratia and Lactobacillus. Metabolomics analysis showed that amino acid metabolism is disrupted during starvation and is restored after refeeding. In summary, this study expands our comprehension of the interaction between oxidative stress and antioxidant defenses among juvenile largemouth bass subjected to starvation and refeeding. [ABSTRACT FROM AUTHOR]

Stochastic optimization approaches benefit from random variance to produce a solution in a reasonable time frame that is good enough for solving the problem. Compared with them, deterministic optimization methods feature faster convergence rates and better reproducibility but may get stuck at a local optimum that is insufficient to solve the problem. In this paper, we propose a group-based deterministic optimization method, which can efficiently achieve comparable performance to heuristic optimization algorithms, such as particle swarm optimization. Moreover, the weighted sum method (WSM) is employed to further improve our deterministic optimization method to be multi-objective optimization, making it able to seek a balance among multiple conflicting circuit performance metrics. With a case study of three common analog circuits tested for our optimization methodology, the experimental results demonstrate that our proposed method can more efficiently reach a better estimation of the Pareto front compared to NSGA-II, a well-known multi-objective optimization approach. [ABSTRACT FROM AUTHOR]

Operational amplifiers (Op-Amps) are critical to sensor systems because they enable precise, reliable, and flexible signal processing. Current automated Op-Amp generation methods suffer from extremely low efficiency because the time-consuming SPICE-in-the-loop sizing is normally involved as its inner loop. In this paper, we propose an efficiently automated Op-Amp generation tool using a hybrid sizing method, which combines the merits together from a deterministic optimization algorithm and differential evolution algorithm. Thus, it can not only quickly find a decent local optimum, but also eventually converge to a global optimum. This feature is well fit to be serving as an acute filter in the circuit structure evaluation flow to efficiently eliminate any undesirable circuit structures in advance of detailed sizing. Our experimental results demonstrate its superiority over traditional sizing approaches and show its efficacy in highly boosting the efficiency of automated Op-Amp structure generation. [ABSTRACT FROM AUTHOR]

Powdery high molecular weight polyacrylonitrile (HMW-PAN) polymers were successfully synthesized by aqueous deposited polymerization (ADP) method with 2,2'-azobis (2-methyl propionamide) dihydrochloride (AIBA) as the initiator and itaconic acid (IA) as comonomer. The utilization of IA into the ADP system was conducive to relax the proceeding of thermo-oxidation process. Differential scanning calorimeter (DSC) curves of obtained PAN copolymers showed the doublet peaks character under air atmosphere, attributing to the exothermic cyclization and oxidative reactions during heat-treatment process. With the utilization of IA in the reaction system, crystallinity and grain sizes of the PAN polymers decreased. The stretching vibration of nitrile group (C≡N) at 2240cm-1 was the strongest peak in both Fourier transform infrared spectra (FTIR). And the stretching vibration and bending of CH2 were the stronger peaks in FTIR. Amido group (NH2), carbonyl group (C=O) and C-O single bond existed in FTIR of PAN homopolymer and copolymers, indicating occurrence of C≡N hydrolysis during polymerization process except carboxyl group (COOH) introduced by IA.

Aqueous batteries exhibite great potential for large-sacle energy storage due to their intrinsic safety, eco-friendliness, and low cost. However, the inadequate capacity and poor cycling stability impede the futher development. Herein, FeS 2 compounded with three-dimensional carbon fibers are designed as the self-supporting cathodes in aqueous copper ion system, where the microporous/mesoporous (within 10 nm) are proposed to improve the rapid electron transfer and strengthen the electrolyte wettability. The results reveal that FeS 2 @CNFs700 exhibits a specific capacity of 462 mAh g−1 after 1600 cycles at 5 A g−1 with low capacity degradation of only 0.022 % and 385 mAh g−1 after 4000 cycles with high coulombic efficiency of 97.5 %, prossessing superior rate performance (387 mAh g−1 at 15 A g−1). Furthermore, the reversible reaction pathway of FeS 2 → CuS → Cu 7 S 4 → Cu 2 S is demonstrated by a series of ex-situ testing, proving the feasibility of FeS 2 in aqueous batteries at ambient temperature. In addition, the assembled Zn//FeS 2 @CNFs hybrid battery exhibits a stable reversible specific capacity of 510 mAh g−1 and a specific energy of 459 Wh kg−1 at 1 A g−1 with an excellent cycling stability (capacity decay: 2.77 % after 50 cycles). This work offers unique insights about stable FeS 2 -aqueous batteries designing. [Display omitted] • Self-supporting cathode is designed by electrostatic spinning. • Microporous (within 10 nm) can efficiently improve the rapid electron transfer. • FeS 2 @CNFs demonstrates excellent stability during long cycle test at 5 A/g. • The reversible reaction pathway of FeS 2.→ CuS → Cu 7 S 4 → Cu 2 S is proved in FeS 2 //Cu battery. • Hybrid battery of FeS 2 //Zn is designed to improve the operational voltage. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries (LSBs) are considered one of the most promising candidate for next-generation storage systems due to their excellent theoretical energy density. Nevertheless, the inevitable "shuttle effect" of soluble lithium polysulfides (LiPSs) leads to poor cycle stability. Herein, we report the in-situ coating MnO2 nanosheets on the Co3O4@C nanospheres (Co3O4@C@MnO2) as modified separators for LSBs. The study shows that the outer layer of MnO2 has a high affinity for LiPSs and can anchor LiPSs through strong chemical adsorption. The internal Co3O4@C has admirable catalytic activity, which can accelerate the complete conversion of LiPSs to Li2S. Benefiting from the synergistic effects between the outer layer MnO2 on the adsorption of LiPSs and the inner Co3O4@C on the catalysis of LiPSs, the cells exhibit an outstanding electrochemical performance, including high reversible capacity of 734 mAh g−1 at 1 C, a low-capacity decay rate of 0.0406% per cycle around 500 cycles. This work provides an impressive method for high-performance LSBs. [ABSTRACT FROM AUTHOR]