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Objective:To perform a meta-analysis of published randomized controlled trials (RCTs) to assess the effects of curcumin supplementation with different formulations on anthropometric and cardiometabolic indices in patients with metabolism-related diseases (MRDs). Methods: Six databases, including PubMed, Embase, Web of Science, China national knowledge internet (CNKI), Wanfang and China Biology Medicine (CBM), were systematically searched to find relevant articles from 2011 to July 2021. The effect sizes were expressed as weighted mean difference (WMD) with 95% confidence intervals (CI). Between-study heterogeneity was assessed using I2. Subgroup analysis was conducted to find possible sources of heterogeneity. Curcumin formulations in this study were divided as low bioavailability, high bioavailability and nanocurcumin. Results: Of the retrieved 1585 articles, 31 were included in the final analysis. Combined effect sizes suggested a significant effect of curcumin supplementation on reduced body weight (BW) (WMD: −0.94 kg, 95% CI: −1.40, −0.47) and body mass index (BMI) (WMD: −0.40 kg/m2, 95% CI: −0.60, −0.19), respectively. The results also showed significant improvements of fasting plasma glucose (FPG) (WMD: −0.50 mg/dL, 95% CI: −0.72, −0.28), glycosylated hemoglobin (Hb1Ac) (WMD: −0.42%, 95% CI: −0.57, −0.26), insulin (INS) (WMD: −1.70 μIU/mL, 95%CI: −2.03, −1.38), homeostasis model assessment-insulin resistance (HOMA-IR) (WMD: −0.71, 95%CI: −1.11, −0.31), high-density lipoprotein cholesterol (HDL-C) (WMD: 1.73 mg/dL, 95%CI: 0.78, 2.68) and high sensitivity C-reactive protein (Hs-CRP) (WMD: −1.11, 95%CI: −2.16, −0.05). Nanocurcumin showed a greater reduction in FPG (WMD: −1.78 mg/dL, 95% CI: −2.49, −1.07), INS (WMD: −1.66 μIU/mL, 95% CI: −3.21, −0.11), TC (WMD: −12.64 mg/dL (95% CI: −23.72, −1.57) and LDL-C (WMD: −8.95 mg/dL, 95% CI: −16.51, −1.38). The dose-effect analysis showed that there were trends of first rising and then falling between the supplemented curcumin dose and BW, BMI, LDL-C, Hb1Ac, which were clearly distinguished at 80 mg/d due to the strong effect of nanocurcumin on outcomes. A slow upward trend between the dose of curcumin supplementation and HDL-C. No relationships between dose and outcomes were found for FPG and insulin, except for nanocurcumin at 80 mg/d. Conclusions: Our study showed some significant beneficial effects of curcumin supplementation on improving BW, BMI, and the levels of FPG, Hb1Ac, HOMA-IR, HDL-C and Hs-CRP in patients with MRDs. Nanocurcumin may have a greater effect on the reduction of FPG, INS, TC and LDL-C than other curcumin formulations. Considering the potential bias and limitations of studies included, further quality studies with larger sample sizes are needed to confirm these results.

It is an extra heavy burden to maintain the distribution network model since of its frequent changing and large scale. In reality, the network model may involve significant parameter errors, which makes the model not applicable. This paper presents a robust data-driven approach to linearize the three-phase power flow. A three-phase linear power flow (LPF) model for active distribution networks (ADNs) is proposed. To address the issues of measurement outliers and data collinearity, the support vector regression (SVR) algorithm is applied to the linearization regression to obtain the proposed three-phase LPF model. The training process is offline and the obtained LPF model can be used to calculate the power flow online. Numerical tests demonstrate that the proposed approach can achieve satisfactory calculation accuracy with high computational efficiency, even under data collinearity and measurement outliers. Since the proposed LPF has very high accuracy, this model can be incorporated into distribution networks optimization problems.

As traditional optimal planning strategies in multi-energy gathering center are only dominated by the economic index, while the flexibility index has not been taken into consideration. This paper creatively proposes a comprehensive evaluation metric of flexibility and economic index based on the multi-scenario operation process and the optimal planning method. A two-level capacity optimization model of different generations in multi-energy gathering center is established in this paper. This model consists of two objectives, the economy index and the flexibility index. The outer model applies the capacity of two flexible resources, thermal power units and battery energy storage units, as decision variables. And the inner model aims at the operating cost and flexibility index as objectives. The combined method of NSGA-II, linear programming and quadratic optimization is adopted to solve the above two-level optimization problem on the basis of fully considering multiple scenarios. Finally, based on the actual data and energy characteristics in a multi-energy gathering center in Yunnan, the proposed planning strategy is verified. Simulation results show that, compared with the traditional planning strategy only considering the economic cost as the main index, this proposed strategy can significantly reduce the energy abandonment and loads’ cutting rate. As a result, the proposed strategy reduces the possibility of grid risks and improves the system reliability and flexibility.

For solving the dynamic instability problem of Yunnan Province Power System (YNPS) and the South China Interconnected Power System (SCIPS), Lubuge hydropower plant was chosen to install a power system stabilizer (PSS). The philosophy to set the parameters of PSS is to provide positive damping within the frequency of 0.4/spl sim/1.6 HZ specially 0.4/spl sim/1.0 HZ and to be adaptive to various operating conditions. Based on the phase compensation and the root-locus method the setting of PSS was chosen. Further eigenvalue and the time domain simulation studies show that the setting is well adaptive to different operating conditions and can significantly improve the system damping. In the field tests, the frequency response measurements and the performance of PSS under different operating condition were carried out. The test results show that the PSS installed can significantly improve the system damping. The PSSs of Lubuge power plant have been put into service in August, 1995 and working well since then. There were several incidents of serious faults occurred in YNPS and SCIPS, no apparent power oscillation observed in generators or tie lines.