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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.

While conventional oxides have a high theoretical specific capacity, they also suffer from severe volume expansion during cycling, which seriously affects the stability of the structure. Hence, high‐entropy oxide nanoparticles (Cr0.2Fe0.2Mn0.2Ni0.2Co0.2)3O4, CFMNC) were synthesized and uniformly dispersed on reduced graphene oxide(rGO) carriers using a solvothermal method‐assisted heat treatment as a novel sodium‐ion batteries anode material. The introduction of rGO does not change the crystal structure of CFMNC material, while loading CFMNC into the sheet structure of rGO forms a highly conductive structure, which promotes electron/ion transfer. The high specific surface area is conducive to the full infiltration of the electrode material with the electrolyte, and improve the electrode activity. The random distribution of individual metal ions in CFMNC makes itself have a strong entropy‐driven structural stabilization effect to achieve the cycling stability: 149.1 mAh g−1 can be maintained at 100 mA g−1 over 200 cycles with capacity decay rate of 0.05 % cycle−1. CFMNC/rGO also have excellent rate capability (76.1 mAh g−1at 3000mAg−1, and returned to 153.6 mAh g−1at 200 mA g−1 with almost 100 % capacity retention). Therefore, the composite is considered to offer research potential for the design of high‐performance anode materials through entropy‐driven strategies. [ABSTRACT FROM AUTHOR]

To meet the growing demand for energy storage technologies, it is crucial to develop next-generation energy storage and conversion devices with superior energy density, safety, low cost, and green sustainability. Li–air batteries (LABs) can catalyze the special redox reaction of light weight metal–oxygen (O2) couples, with superb theoretical energy density, low cost, and environmental friendliness, making them suitable for large-scale electricity storage technologies. However, an in-depth understanding of the root causes of poor battery performance and a well-defined electrochemical mechanism based on structural or material properties are still lacking. Hence, we discuss the main obstacles to the sluggish kinetics of the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) at the cathode in LABs in this review. Exploration of a special redox reaction based on the design of the catalyst material is extremely instructive for battery development. Various design/manufacturing methods for nanoscale bifunctional electrocatalysts are introduced to offer general design principles. Electrocatalysts involve alloys, transition metal oxides (manganese-based, cobalt-based), other transition metal compounds (carbides/nitrides/sulfides), and carbon materials. The effects of different crystal structure designs on the bifunctional electrocatalytic mechanism of the OER/ORR are investigated at the nanoscale to guide performance improvement strategies. In addition, the root causes of poor battery performance caused by other components are discussed, as well as their possible future breakthroughs. Finally, the prospects of LABs should be highly focused on an integrated mechanism–structure–property strategy to guide catalyst synthesis and further integration with practical parameters for device development. [ABSTRACT FROM AUTHOR]

The proton exchange membrane fuel cell now ranks as one of the best alternatives to fossil fuels. Two optimization techniques that have stirred up a lot of controversy include reducing the amount of precious metal Pt catalysts and boosting the kinetics of the cathodic oxygen reduction reaction (ORR). Herein, "template‐etching" method is used to create N−P co‐doped low‐Pt catalysts with hierarchical porous carbon nanospheres (Pt/NPC). The P atoms′ valence electrons, which serve to attach the Pt to the equally disseminated N atoms, further disperse the Pt inside the carbon nanospheres. As a result, the Pt is able to modify the electronic structure and alter the d‐band center, which raises the intrinsic ORR activity. The hierarchical porous structure of the carbon nanospheres, created by the phytic acid activation of the pores, can expose more active sites and efficiently enhance the transfer of oxygen and electrons, increasing the catalytic efficiency. The catalysts synthesized using this method had great stability, 9.87 wt % Pt concentration, and half‐wave potential of 0.832 V for acidic intermediates and 0.855 V for alkaline intermediates. Because of its entire pH ORR catalytic capabilities, this catalyst exhibits tremendous application potential for replacing conventional Pt/C catalysts. [ABSTRACT FROM AUTHOR]

The development of cheap, high-efficiency, and stable oxygen evolution reaction (OER) electrocatalysts is a current research hotspot. In this work, reduced graphene oxide (rGO) composite Ni 3 S 2 microspheres grown directly on nickel foam (Ni 3 S 2 -rGO/NF) were prepared by tube furnace calcination and hydrothermal method. The Ni 3 S 2 -rGO/NF had excellent OER catalytic activity and stability with an overpotential of 303 mV at the current density of 100 mA cm−2, which was 100 mV lower than that of Ni 3 S 2 /NF, and its Tafel slope was as low as 23 mV·dec−1. The main reason for enhancing OER activity of the Ni 3 S 2 -rGO/NF is due to synergistic effect of Ni 3 S 2 microspheres and rGO, which inhibited the production of NiS and refined the micron size of Ni 3 S 2. This work offers a new method for developing stable and efficient OER catalysts. • Ni 3 S 2 -rGO/NF were prepared successfully. • Excellent catalytic activity: an overpotential of 185 mV at 10 mA cm−2. • NF used acted as support material and nickel source for situ formation of catalysts. • The Ni 3 S 2 grow on the rGO micro flakes and formed to a conductive network. • The synergistic effect of Ni 3 S 2 microspheres and rGO enhanced the OER performance. [ABSTRACT FROM AUTHOR]