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Introduction: An innovative methodology is proposed to delve into the pivotal role of regional distribution networks (RDNs) in fostering low-carbon development. Methods: The methodology first constructs an evaluation framework encompassing various dimensions and then integrates spherical fuzzy sets (SFSs) with the best-worst method (BWM), enabling the precise calculation of indicator weight parameters. Subsequently, we employ the measurement of alternatives and ranking according to compromise solution (MARCOS) with SFSs to process and synthesize decision making information. Results: Take the Shanghai region as an example, results show that C4 has the highest performance and C10 has the lowest. Discussion: In conclusion, this research presents a significant step forward in understanding the importance of RDNs in promoting low-carbon development and offers a practical approach for decision-makers to assess and enhance the performance of RDNs. [ABSTRACT FROM AUTHOR]

Due to real-time fluctuations in wind farm output, large-scale renewable energy (RE) generation poses significant challenges to power system stability. To address this issue, this paper proposes a deep reinforcement learning (DRL)-based electric hydrogen hybrid storage (EHHS) strategy to mitigate wind power fluctuations (WPFs). First, a wavelet packet power decomposition algorithm based on variable frequency entropy improvement is proposed. This algorithm characterizes the energy characteristics of the original wind power in different frequency bands. Second, to minimize WPF and the comprehensive operating cost of EHHS, an optimization model for suppressing wind power in the integrated power and hydrogen system (IPHS) is constructed. Next, considering the real-time and stochastic characteristics of wind power, the wind power smoothing model is transformed into a Markov decision process. A modified proximal policy optimization (MPPO) based on wind power deviation is proposed for training and solving. Based on the DRL agent's real-time perception of wind power energy characteristics and the IPHS operation status, a WPF smoothing strategy is formulated. Finally, a numerical analysis based on a specific wind farm is conducted. The simulation results based on MATLAB R2021b show that the proposed strategy effectively suppresses WPF and demonstrates excellent convergence stability. The comprehensive performance of the MPPO is improved by 21.25% compared with the proximal policy optimization (PPO) and 42.52% compared with MPPO. [ABSTRACT FROM AUTHOR]

Heat stress resulting from global climate change has been demonstrated to adversely affect growth, development, and reproduction of marine organisms. The Zhikong scallop (Chlamys farreri), an important economical mollusk in China, faces increasing risks of summer mortality due to the prolonged heat waves. The heart, responsible for transporting gas and nutrients, is vital in maintaining homeostasis and physiological status in response to environmental changes. In this study, the effect of heat stress on the cardiac function of C. farreri was investigated during the continuous 30-day heat stress at 27 °C. The results showed the heart rate of scallops increased due to stress in the initial phase of high temperature exposure, peaking at 12 h, and then gradually recovered, indicating an acclimatization at the end of the experiment. In addition, the levels of catalase (CAT), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC) exhibited an initial increase followed by recovery in response to heat stress. Furthermore, transcriptome analysis of the heart identified 3541 differentially expressed genes (DEGs) in response to heat stress. Subsequent GO and KEGG enrichment analysis showed that these genes were primarily related to signal transduction and oxidative stress, such as the phosphatidylinositol signaling system, regulation of actin cytoskeleton, MAPK signaling pathway, FoxO signaling pathway, etc. In addition, two modules were identified as significant responsive modules according to the weighted gene co-expression network analysis (WGCNA). The upregulation of key enzymes within the base excision repair and gap junction pathways indicated that the heart of C. farreri under heat stress enhanced DNA repair and maintained cellular integrity. In addition, the variable expression of essential signaling molecules and cytoskeletal regulators suggested that the heart of C. farreri modulated cardiomyocyte contraction, intracellular signaling, and heart rate through complex regulation of phosphorylation and calcium dynamics in response to heat stress. Collectively, this study enhances our understanding of cardiac function and provides novel evidence for unraveling the mechanism underlying the thermal response in mollusks. [ABSTRACT FROM AUTHOR]

The meniscus-confined electrodeposition (MCED) technique offers advantages such as low cost and wide applicability, making it a promising method in the field of micro/nanofabrication. However, unstable meniscal morphology and poor deposition quality during planar deposition in MCED necessitate the development of improved methods. Therefore, a planar adaptive micro-tuning deposition method (PAMTDM), which utilizes the positioning technology of scanning electrochemical cell microscopy (SECCM) and employs a singular value decomposition (SVD) planar fitting method to determine the flatness of the deposition plane, is proposed. An adaptive micro-tuning motion mode was proposed by analyzing the variation patterns of the meniscus. Moreover, a combination of multi-physics finite element simulations and orthogonal experimental methods was introduced to determine the optimal motion parameters. The experimental results demonstrate that the PAMTDM effectively addresses the issues encountered during planar growth. Compared to the point-by-point deposition method, the PAMTDM achieves a threefold increase in deposition speed for continuous deposition of 105-μm-long line segments in two-dimensional planes, with a deposition current error of less than 0.2 nA. In conclusion, the proposed method provides significant insights into the broad future applications of MCED. [ABSTRACT FROM AUTHOR]

Cobalt has the highest Curie temperature (Tc) among the elemental ferromagnetic metals and has a hexagonal close-packed (HCP) structure at room temperature. In this study, HCP Co was thinned to the thickness of several (n) unit cells along the c-axis and then passivated by halogen atoms, thus being named Co2nX2 (X = F, Cl, Br and I). For Co2X2 and Co3X2, all of them are not only kinetically but also thermodynamically stable from the viewpoint of the phonon spectra and molecular dynamics. Similar to HCP Co, two-dimensional (2D) Co2F2, Co2Cl2 and Co3X2 (X = Cl, Br and I) are still ferromagnetic metals within the Stoner model but Co2X2 (X = Br and I) is a ferromagnetic half-metal with the coexistence of the metallic behavior for one spin and the insulating behavior for the other spin. Taking into account the spin-orbital coupling (SOC), the easy-magnetization axis is within the plane where the magnetization is isotropic, making it look like a 2D XY magnet. Applying a critical biaxial strain could lead to an easymagnetization axis changing from the in-plane to the out-of-plane direction. Finally, we use classical Monte Carlo simulations to estimate the Curie temperature (Tc) which is as high as 957 and 510 K for Co2F2 and Co2Cl2, respectively, because of the strong direct exchange interaction. Different from being obtained by mechanical or liquid exfoliation from van der Waals layered structures, our study opens up new possibilities to search for novel 2D ferromagnets from the elemental ferromagnets and provides opportunities for realizing realistic ultra-thin spintronic devices. [ABSTRACT FROM AUTHOR]

Inorganic molecular crystal films, particularly α-Sb2O3, have emerged as promising van der Waals (vdW) dielectrics for the large-scale integration of two-dimensional (2D) semiconductors in field-effect transistors (FETs) [K. L. Liu, B. Fin, W. Han, X. Chen, P. L. Gong and L. Huang, et al., Nat. Electron., 2021, 4, 906.]. Nevertheless, a notable gap exists in understanding the electronic and dielectric characteristics of few-layer α-Sb2O3 and the underlying physics governing its interaction with common 2D semiconductors. Herein, we address such issues through first-principles calculations. As the layer number increases, the electronic properties (e.g., band gap and band edges) of α-Sb2O3 exhibit minimal variations, resembling the electronic decoupling behavior, while the out-of-plane high dielectric constant significantly rises, indicating significant surface ionic behavior. These features stem from the weak interlayer quasi-bonding interaction, small atomic Born effective charge at the surface, and the influence of surface-to-volume ratio. Furthermore, exploring device physics, with a focus on complementary metal-oxide-semiconductor FETs, demonstrates that the leakage currents between the N-layer α-Sb2O3 (N ≥ 4) and all our studied 2D semiconducting channels adhere to international standards and the dielectrics with 4 and 5 layers meet the criteria for small equivalent oxide thickness. Unlike other layered vdW dielectrics, few-layer α-Sb2O3 emerges as a novel high-k vdW dielectric with exceptional dielectric performance and distinctive electronic characteristics, inspiring further exploration of inorganic molecular crystals for vdW dielectrics in integrated 2D semiconductor devices. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to explore the link between dietary vitamin C intake and hyperuricemia/gout, utilizing Mendelian randomization to assess causality. Methods: We analyzed cross‐sectional data from the National Health and Nutrition Examination Survey (2007–2018) to investigate the association. Mendelian randomization studies, using genetic data from genome‐wide association surveys, were conducted to infer causality between vitamin C intake and hyperuricemia/gout. The weighted logistic regression analysis and the instrumental variable based on the inverse‐variance weighting served as the primary analytical tool, with sensitivity analyses to ensure robustness. Results: After adjusting for covariates, a stable association was observed between vitamin C intake and hyperuricemia/gout risk. Those consuming >111.75 mg of vitamin C generally had a lower risk. Vitamin C intake recommendations of 75–525 mg and 75–225 mg appeared effective for hyperuricemia and gout, respectively. Mendelian randomization analysis revealed a negative association between vitamin C intake and hyperuricemia (OR = 0.985, 95% CI = 0.973–0.997, p =.015) and gout (OR = 0.857, 95% CI = 0.797–0.921, p <.001). Reverse Mendelian randomization indicated no reverse causality. Conclusion: We hypothesize that a dietary vitamin C intake of 75–525 mg or 75–225 mg may reduce the risk of hyperuricemia and gout, respectively. Further research with larger samples is required to confirm this. [ABSTRACT FROM AUTHOR]