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The volatility impact and insufficient level of new energy accommodation brought by the high proportion of new energy connected to the grid have become an urgent problem to be solved under the background of new type power system. Therefore, based on the characteristics that the increase of prediction accuracy of wind, photovoltaic power and load improves step by step with reduced time scales and the flexible regulation ability of pumped storage plant, a multi-time scale coordinated dispatching model of wind-photovoltaic-pumped storage zero-carbon power system is established. In order to minimize the cost of power generation, the power generation plans of day-ahead 24-hour, the intraday 1-hour and the real-time 15-minute are established. Through the coordination of multiple time scales, the wind power, photovoltaic power and pumped storage output track the load well, thus revising the power generation plan step by step. Taking the wind-photovoltaic-pumped storage zero-carbon power system with 6 pumped storage units as an example, the simulation analysis shows that the proposed multi-time scale coordinated dispatching model is conductive to reducing curtailment of wind and photovoltaic power, and the ability of power system to accommodate wind and photovoltaic power is related to the installed capacity of pumped storage plant.

Cold plasma is used to sterilize meat and reduce endogenous enzyme activity for meat preservation because it can generate reactive nitrogen species (RNS) and reactive oxygen species (ROS). RNS can be an alternative to nitrite in meat products; however, the active particles have a nonnegligible impact on meat components especially protein and fat. Excessive oxidation of meat products will cause quality deterioration. In this paper, the action modes of cold plasma technology on meat proteins and meat products are reviewed, as well as its regulatory effect and mechanism on the structure and function of myofibrillar protein and myoglobin in meat, and the current status of research on the application of cold plasma technology in meat preservation and processing is outlined. This systematic review is expected to provide a reference for the wide application of cold plasma technology in the meat industry.

Engineering enzyme–substrate binding pockets is the most efficient approach for modifying catalytic activity, but is limited if the substrate binding sites are indistinct. Here, we developed a 3D convolutional neural network for predicting protein–ligand binding sites. The network was integrated by DenseNet, UNet, and self-attention for extracting features and recovering sample size. We attempted to enlarge the dataset by data augmentation, and the model achieved success rates of 48.4%, 35.5%, and 43.6% at a precision of ≥50% and 52%, 47.6%, and 58.1%. The distance of predicted and real center is ≤4 Å, which is based on SC6K, COACH420, and BU48 validation datasets. The substrate binding sites of Klebsiella variicola acid phosphatase (KvAP) and Bacillus anthracis proline 4-hydroxylase (BaP4H) were predicted using DUnet, showing high competitive performance of 53.8% and 56% of the predicted binding sites that critically affected the catalysis of KvAP and BaP4H. Virtual saturation mutagenesis was applied based on the predicted binding sites of KvAP, and the top-ranked 10 single mutations contributed to stronger enzyme–substrate binding varied while the predicted sites were different. The advantage of DUnet for predicting key residues responsible for enzyme activity further promoted the success rate of virtual mutagenesis. This study highlighted the significance of correctly predicting key binding sites for enzyme engineering. [ABSTRACT FROM AUTHOR]

Inherited retinal degenerations (IRDs) are a group of genetic disorders characterized by the progressive degeneration of retinal cells, leading to irreversible vision loss. SLC4A7 has emerged as a candidate gene associated with IRDs, yet its mechanisms remain largely unknown. This study aims to investigate the role of slc4a7 in retinal development and its associated molecular pathogenesis in zebrafish. Morpholino oligonucleotide knockdown, CRISPR/Cas9 genome editing, quantitative RT-PCR, eye morphometric measurements, immunofluorescent staining, TUNEL assays, visual motor responses, optokinetic responses, rescue experiments, and bulk RNA sequencing were used to assess the impact of slc4a7 deficiency on retinal development. Our results demonstrated that the knockdown of slc4a7 resulted in a dose-dependent reduction in eye axial length, ocular area, and eye-to-body-length ratio. The fluorescence observations showed a significant decrease in immunofluorescence signals from photoreceptors and in mCherry fluorescence from RPE in slc4a7-silenced morphants. TUNEL staining uncovered the extensive apoptosis of retinal cells induced by slc4a7 knockdown. Visual behaviors were significantly impaired in the slc4a7-deficient larvae. GO and KEGG pathway analyses reveal that differentially expressed genes are predominantly linked to aspects of vision, ion channels, and phototransduction. This study demonstrates that the loss of slc4a7 in larvae led to profound visual impairments, providing additional insights into the genetic mechanisms predisposing individuals to IRDs caused by SLC4A7 deficiency. [ABSTRACT FROM AUTHOR]

Dielectric capacitors, which can achieve tremendous power density and ultrafast charge/discharge speed, are crucial components for high power equipment. Yet, the synchronous achievement in high recoverable energy density (Wrec) and high efficiency (η) is a long‐term difficulty for dielectric ceramics. Herein, the (0.85 − x)NaNbO3–0.15BaTiO3–xBi(Mg1/3Ta2/3)O3 (NN–BT–xBMT) relaxor ferroelectric ceramics were proposed and studied. The doping of BMT was conducive to promoting the microstructure and bandgap and improving the dielectric relaxation properties of NN–BT ceramics. Finally, the sample of x = 0.10 presented a high Wrec of 5.9 J/cm3 and a high η of 90% simultaneously. In addition, the sample also exhibited superb charge/discharge performances with large power density (PD = 137 MW/cm3) and fast charge/discharge speed (t0.9 = 39 ns). The above results reveal that the NaNbO3‐based ceramics could serve as potential alternatives for advanced dielectric capacitors. [ABSTRACT FROM AUTHOR]

Study Objective. Sugammadex is a widely used neuromuscular blockade reversal agent. Cost concerns limit use in pediatric patients for, whom recommended doses are often far less than vial quantities. Therefore, we undertook a quality improvement initiative at a pediatric hospital in which sugammadex vials were fractionated. We hypothesized we would see a decrease in administered dose and waste and improved adherence with dosing guidelines. Methods. Sugammadex vials were fractionated into 25, 50, or 100 mg aliquots, which would be distributed to anesthesia staff by pharmacy staff in approximate 2 mg/kg of actual body weight doses (±10%). We analyzed changes in sugammadex waste and dosing practices 1/1/2019 to 3/15/2023 pre/postintervention (4/1/2021). We gauged dose appropriateness using last train of four (TOF) prior to sugammadex administration. Results. 7,889 patients 2–17 years (4,771 with documented TOF), ASA 1–4 receiving general anesthesia with a steroidal NMB medication and sugammadex reversal. Pre‐ and postintervention mean doses were 2.5 mg/kg (SD: 1.2) and 2.4 mg/kg (SD: 0.96), respectively. A smaller proportion of cases received standard 2 or 4 mg/kg doses (pre: 77.6 vs. post: 66.7%). Mean waste per case declined from 4.2 mg/kg (SD: 4.1) to 0.22 mg/kg (SD: 0.38). Among cases with 0 or 1 measured twitches on TOF that should receive at least 4 mg/kg, fewer received at least 3.6 mg/kg (post: 56.7% vs. pre: 66.8%), and a greater proportion received less than 2.2 mg/kg (post: 27.4% vs. pre: 20.7%). Among cases that should have received at least 2 mg/kg by TOF, the proportion of patients receiving more than 3.6 mg/kg declined from 9.5% to 5.2%. Discussion. Fractionating sugammadex vials was associated with decreases in waste, but not dose, and significant underdosing was more likely to occur. While vial fractionation could enable increased access to sugammadex and other costly medications, it may introduce unintended consequences. [ABSTRACT FROM AUTHOR]

In the context of low-pressure casting, an excessive inlet velocity may result in the introduction of an oxide film and air into a liquid metal, leading to the formation of a two-layer film structure within the casting. Such defects can significantly degrade the mechanical properties of the castings. In order to optimize the advantages of low-pressure casting, an empirically designed equation for the inlet velocity was formulated and the concept of critical inlet velocity was further refined. A comprehensive numerical simulation was conducted to meticulously analyze the liquid metal spreading phase within the cavity. Subsequently, low-pressure casting experiments were carried out with actual castings of an A357 alloy, using two different entrance velocities—one critical and the other exceeding the critical entrance velocity. Tensile test specimens were extracted from the castings for the comparative evaluation of mechanical properties. It was observed that the average tensile strength of specimens cast at the critical inlet velocity exhibited a notable 16% enhancement. In contrast, specimens cast at velocities exceeding the critical inlet velocity manifested the presence of double oxide film defects. This evidence suggests that casting at a velocity faster than the critical inlet velocity leads to the formation of double oxide film defects, which in turn reduces the mechanical properties of the castings. [ABSTRACT FROM AUTHOR]

Refractory high-entropy alloys (RHEAs) typically exhibit excellent high-temperature strength but limited ductility. In this study, a comprehensive machine learning strategy with integrated material knowledge is proposed to predict the elongation of TiZrNbVAl RHEAs. By referring to the ductility theories, a set of cost-effective material features is developed with various mathematical forms of thermodynamic parameters. These features are proven to effectively incorporate material knowledge into ML modeling. They also offer potential alternatives to those obtained from costly first-principles calculations. Based on Pearson correlation coefficients, the linear relationships between pairwise features were compared, and the seven key features with the greatest impact on the model were selected for ML modeling. Regression tasks were performed to predict the ductility of TiZrNbVAl, and the CatBoost gradient boosting algorithm exhibiting the best performance was eventually selected. The established optimized model achieves high predictive accuracies exceeding 0.8. These key features were further analyzed using interpretable ML methods to elucidate their influences on various ductility mechanisms. According to the ML results, different compositions of TiZrNbVAl with excellent tensile properties were prepared. The experimental results indicate that Ti44Zr24Nb17V5Al10 and Ti44Zr26Nb8V13Al9 both exhibited ultimate tensile strengths of approximately 1180 MPa and elongations higher than 21%. They verified that the ML strategy proposed in this study is an effective approach for predicting the properties of RHEAs. It is a potential method that can replace costly first-principles calculations. Thermodynamic parameters have been shown to effectively predict alloy ductility to a certain extent. [ABSTRACT FROM AUTHOR]

Ceramic capacitors are receiving increasing interest because of their applications in pulsed-power devices. The perovskite oxide Bi0.5Na0.5TiO3 (BNT)-based ferroelectric ceramics are regarded as prospective lead-free candidate for dielectric capacitors because of the high polarization and outstanding relaxor behaviour. Herein, the relaxor ferroelectric (0.7−x)Bi0.5Na0.5TiO3–0.3SrTiO3–xCa0.7Sm0.2TiO3 ceramics synthesized through solid-state route and exhibited pseudocubic perovskite structure and strong relaxor behaviour. With increasing Ca0.7Sm0.2TiO3 content, the moderate permittivity and reduced grain size contributed to the monotonically increased electric breakdown strength. Among prepared samples, the x = 0.2 ceramic displayed slimmer polarization-electric field curves with a remarkable recoverable energy density (~6.8 J/cm3) and a satisfied efficiency (~82.2%) under external electric field of 450 kV/cm. Moreover, the x = 0.2 ceramic also exhibited a superb thermal reliability of energy storage properties (3.9–4.5 J/cm3 with variation of 13.3% in 25–160 °C) resulting from the diffuse phase transition. The above results make the x = 0.2 ceramics becoming promising candidates for pulsed-power devices. [ABSTRACT FROM AUTHOR]