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[Objective] The resource sharing among main substations in urban rail transit power supply system can lead to significant cost savings. In this context, it is essential to investigate reactive power compensation schemes for different phases of main substation resource sharing to ensure that the power factor at the PCC (point of common coupling) meets the standards. [Method] Taking the power supply system of a city's metro line as example, based on the train schedule and power supply system structure, the minimum reactive power compensation required at PCC before and after main substation resource sharing under daily power factor compliance is calculated. A reactive power compensation setting scheme considering main substation resource sharing is proposed, based on the minimum reactive power compensation that meets the compensation requirements before and after main substation resource sharing, with the goal to minimize SVG (static var generators) capacity, determining the installation capacity of SVG and reactor or capacitator. [Result & Conclusion] In the power supply system of the case study line, the actual configuration of the reactive power compensation devices for the 1# main substation main transformer power supply zone is as follows: reactor capacity is 6.0 Mvar, and SVG capacity is 1.0 Mvar. For the 2# main transformer power supply zone, the configuration is a reactor capacity of 3.0 Mvar and an SVG capacity of 0.5 Mvar. The proposed reactive power compensation scheme replaces a total capacity of 9.0 Mvar SVG devices with reactors, meeting the reactive power compensation requirements while reducing investment costs.

In this study, the release of free fat acids (FFA) from and the digestion characteristics of curcumin nanoemulsions constructed using whey protein isolate (WPI)-(-)-epigallocatechin-3-gallate (ECGG) graft copolymers with 3% and 4% grafting degrees as emulsifiers were investigated during in vitro simulated digestion and compared with those of curcumin nanoemulsions stabilized by WPI. It was found that binding to EGCG might cause the unfolding of WPI, and the interfacial film thickness of the WPI-EGCG stabilized emulsion increased by 31.6 nm compared with that of the WPI stabilized emulsion. The WPI-EGCG complex stabilized emulsion had a smaller particle size dispersion and average particle size than the WPI stabilized emulsion and was therefore more stable and superior in promoting lipid digestion. After 120 minutes of intestinal digestion, the final release rate of FFA from the nanoemulsion stabilized with 4% WPI-EGCG was 85.13%. Also, the graft treatment improved the bioaccessibility of curcumin encapsulated in the system.

Background Identifying insulin resistance (IR) is of important clinical value as it is a pathological basis of multiple diseases, such as metabolic syndrome, type 2 diabetes, hypertension, and atherosclerosis. Numerous previous studies have suggested that excessive gain of fat is closely associated with IR. Dual-energy X-ray absorptiometry is often clinically used as the golden standard for measuring human body fat, but its health economic cost is high. Objective To assess the associations of predicted fat mass (pFM) and predicted fat percent (pFP) with IR in a middle-aged and elderly population without diabetes in Chengdu. Methods In May 2007, a cross-sectional survey was conducted by trained medical workers in Chenghua District, Chengdu, Sichuan. A total of 711 middle-aged and elderly individuals were selected as surveyees by random cluster sampling, and 570 of them were included for analysis after excluding 141 with diabetes. The survey includes filling in a standardized questionnaire, a physical examination, and a laboratory test. The homeostasis model assessment of IR (HOMA-IR) , pFM, and pFP were calculated. Results Among the 570 subjects, the range of HOMA-IR was from 0.01 to 5.50, with a median value of 1.05 (0.72, 1.53) ; the range of pFM was from 2.34 to 41.41 kg, with a value of mean (SD) of (18.59±6.47) kg; the range of pFP was from 13.95% to 48.46%, with a median value of 28.97 (23.77, 37.39) %. The prevalence of IR was 20.17% (115/570) . The results suggested the HOMA-IR value and IR prevalence increased with the increase of pFM and pFP (P