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With the deepening of the coupling degree between power network and natural gas network, the traditional independent optimal scheduling of transmission and distribution integrated electricity–gas systems cannot make full use of the flexible control ability of various resources and the complementary support capabilities between different energy systems. Therefore, this paper puts forward a cooperative optimization scheduling model of transmission–distribution​ integrated electricity–gas systems (TD-IEGS). The coordinated operation of multi-energy coupling devices including gas-fired units, combined heat and power (CHP) units and electric boilers (EB) are considered in this paper to enhance system operation flexibility and economy. The second order cone relaxation (SOCR) method is utilized to tackle the non-linear power and gas flow constraints, and the proposed mixed-integer non-linear programming co-optimization scheduling model is transformed into a mixed integer second order cone programming model (MISOCP). Case studies demonstrate that compared with the independent operation mode, the proposed co-optimization scheduling model of TD-IEGS can reduce total operation cost by about 6.7% under 50% wind power penetration level. Moreover, the co-optimization of TD-IEGS can promote wind power utilization especially in a high share of wind energy.

The paper discusses the properties of the partial fractional integrals, the partial fractional derivatives, and the composite fractional integrals and derivatives. Some basic formulas are derived; and the relations between the Riemann-Liouville and Caputo ones are also presented. Finally, as the specific application, a two dimensional Abel integral equation is solved.

Objective: To systematically evaluate the characteristics of gut microbiota in patients with heart failure (HF).Method: PubMed, Embase, Cochrane Library, Web of Science, CNKI, VIP, Wangfang Data and CBM databases were searched from inception to June 2023.Results: A total of 21 case-control studies involving 869 HF patients and 925 healthy controls were included in the systematic review. The results showed that the α diversity of gut microbiota was decreased and the β diversity was significantly separated in HF patients compared with healthy controls. The relative abundance of Actinobacteria and Proteobacteria was increased, while that of Firmicutes and Bacteroidetes was decreased. The relative abundance of Enterobacteriaceae was increased. The relative abundance of Escherichia-Shigella, Enterococcus, Escherichia coli, Yeast like Fungi, Klebsiella, and Streptococcus was increased, while that of Bifidobacterium, Bacteroides, and Lactobacillus was decreased.Conclusion: Patients with heart failure have decreased diversity of gut microbiota, decreased abundance of beneficial bacteria, and increased abundance of harmful bacteria. Considering the limitations of the existing studies, further large-sample, high-quality studies are needed to verify the above conclusions. [ABSTRACT FROM AUTHOR]

Background: Heart failure with reduced ejection fraction (HFrEF) is a prevalent cardiovascular disease globally, posing a significant burden on healthcare and society. Left ventricular remodelling is the primary pathology responsible for HFrEF development and progression, leading to increased morbidity and mortality. Pueraria, a traditional Chinese herbal medicine and food, is commonly used in China to treat HFrEF. Accumulating evidence suggests that pueraria can effectively reverse left ventricular remodelling in HFrEF patients. This meta-analysis aims to assess the impact of pueraria on left ventricular remodelling in HFrEF patients. Methods: Eight electronic databases, including PubMed, EMBASE, Clinicaltrials.gov, Cochrane Library, Wanfang, CNKI, CQVIP, and CBM were searched for literature from inception to June 2023. All randomized controlled trials (RCTs) using pueraria in the treatment of HFrEF were included. The Cochrane Risk of Bias tool was utilized for RCTs' methodological evaluation, while Review Manager 5.4.1 was used to analyze the data. Results: Nineteen RCTs with a total of 1,911 patients (1,077 males and 834 females) were identified. Meta-analysis indicated that combination medication of pueraria and conventional medicine (CM) was superior to the CM alone in raising left ventricular ejection fraction (LVEF; MD = 6.46, 95% CI, 4.88 to 8.04, P < 0.00001), and decreasing left ventricular end-diastolic diameter (LVEDD; MD = -4.78, 95% CI, -6.55 to -3.01, P < 0.00001), left ventricular end-Systolic diameter (LVESD; MD = -3.98, 95% CI, -5.98 to -1.99, P < 0.00001) and N-terminal pro-brain natriuretic peptide (NT-proBNP; MD = -126.16, 95% CI, -185.30 to -67.03, P < 0.0001). Besides, combination medication improved clinical efficacy rate (RR = 3.42, 95% CI, 2.54 to 4.59, P < 0.00001), 6-min walk test (6-MWT; MD = 65.54, 95% CI, 41.77 to 89.31, P < 0.00001), and TCM syndrome score efficacy (RR = 3.03, 95% CI, 1.57 to 5.83, P = 0.0009). Regarding safety, no difference was observed for adverse events (RR = 0.59, 95% CI, 0.22 to 1.54, P = 0.28). Conclusion: The use of pueraria combined with conventional medicine in HFrEF patients has superiority over conventional medicine alone in ameliorating cardiac function and reversing left ventricular remodeling. Moreover, combination medication has no increase in adverse drug events. Given some limitations, more prudence and high-quality clinical trials are needed in the future to verify the conclusions. [ABSTRACT FROM AUTHOR]

Three-dimensional atom probe has been applied to investigate the solubility of Si in Al3Sc in an Al–0.16Sc–0.05Si alloy. It was found that L12-structured Si-containing Al3Sc precipitates formed after the alloy was aged at 300°C. Results of first-principles calculation indicated that Si atoms tend to substitute Al sites in Al3Sc, and thus the precipitates can be represented as (Al,Si)3Sc. The (Al,Si)3Sc was found to have a dramatic precipitation-strengthening effect in the cast alloy. [Copyright &y& Elsevier]