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New equipment and technical applications on distribution networks demonstrate a tendency of physical data integration， and distribution network morphology is also changing rapidly. Therefore， adaptability testing and verification on new equipment and technology are required to improve distribution network reliability and resource scheduling capability. To this end， the construction and application of real tests for intelligent distribution networks are studied. Firstly， the purpose of the platform and system composition are analyzed. Secondly， the specific implementation methods of power， neutral point test platform， medium-voltage AC/DC architecture test platform， distribution cables， channel test platform， and other platforms are introduced. Finally， three major test scenarios are designed： earthing test 10 kV primary and secondary fusion circuit breaker， functional assessment test on intelligent fully automatic FA， and fault sensing test on low-voltage transformer area. The true test platform for intelligent distribution networks is applied to make up for the deficiency of the traditional testing methods for distribution networks and equipment.

This paper centers on the core business application—the automatic topology identification in transformer areas—of distribution IoT with new energy as its mainstay. It proposes an automatic topology identification technology testing scheme that considers identification reliability， high identification accuracy， and anti-disturbance capability. Besides， a unique “edge-to-end” interaction test platform for the distribution IoT area is developed. Afterward， the functions and performance of the mainstream technical schemes of Zhejiang Electric Power Co.， Ltd. are evaluated in all aspects. The “active current injection plus frequency-domain signal detection” is selected as the optimal technical scheme for topology identification. The topology identification technology testing and research can lay the application foundation for the subsequent interconnection， intercommunication， and interoperability of the distribution IoT and the transformation of the distribution networks.

It has been a popular topic recently that eco-friendly materials， in place of any other kinds， are used as insulation media for power equipment. So far， the relevant research mostly focuses on the performance optimization of eco-friendly insulating materials. However， little attention is paid to whether or not it can be applied to power distribution equipment. Therefore， performance differences between key equipment in transformation areas for which eco-friendly and traditional insulation media are used respectively. Then， eco-friendly insulation media are used to manufacture distribution transformers， switching cabinets， and power cables， and the electrical performance of the media is evaluated. Finally， a distribution transformer area based on eco-friendly power equipment is constructed. The results show that the eco-friendly power equipment prepared by using vegetable insulating oil， gas mixture C4F7N/CO2 （perfluoroisobutyronitrile/carbon dioxide）， and cable insulation material polypropylene is similar in performance to traditional equipment； it can meet the application demands of power equipment on distribution networks. The results also verify the practicability of power equipment made from eco-friendly insulating media and the compatibility between various equipment， which can provide a reference for implementing and promoting eco-friendly distribution networks in China.

ObjectiveTo explore the effects of anxiety and depression on Internet gaming disorder in medical students， and to evaluate the moderating effect of gender， so as to provide references for the prevention and intervention of Internet gaming disorder in medical students.MethodsIn November 2021， a total of 11 771 medical students from a medical college in Sichuan province participated in an online survey through Wenjuanxing platform. Participants completed the Self-rating Anxiety Scale （SAS）， Self-rating Depression Scale （SDS） and the nine-item Internet Gaming Disorder Scale-Short Form （IGDS9-SF）. Then a hierarchical multiple regression analysis was conducted to discuss the moderating role of gender in the relationships between anxiety， depression and Internet gaming disorder in medical students.Results①Males scored lower on SDS （t=-8.302， P

By aggregating the scattered dispatchable resources in power grids through dispatchable resource aggregation technology， coordination and control technology， and power market trading technology， virtual power plants （VPPs） have brought about mutually interactive operation in a friendly manner. Firstly， the paper summarizes the responsiveness assessment technology for dispatchable resource and the differentiated resource aggregation methods for participation in power markets in terms of VPP- aggregated modeling technology. Secondly， it analyzes different modes of VPP resource organization and market participation aimed at demand-side response and power spot market. Lastly， the paper analyzes key issues of VPPs for new power systems and has a full view of risk management， external environment， market promotion， as well as security potentially incurred by multiparty participation.

Layered transition metal dichalcogenides are of intensive interest for potassium‐ion batteries (PIBs) due to their high theoretical capacity, relatively low working potential, and layered structures. However, the limited interlayer spacing poses challenges in accommodating large‐radius potassium ions, significantly affecting their rate and cycling performances, particularly for selenide counterparts. Herein, a class of the strongly coupled NbSe2 nanosheets (NSs)/graphene (G) heterostructure with expanded interlayer spacings and high electron conductivity for boosting the performance of potassium storage is reported. NbSe2 NSs/G delivers a reversible capacity of 348.4 mAh g−1 at 0.05 A g−1, exceptional rate performance (117.5 mAh g−1 at an ultrahigh current density of 10.0 A g−1), and excellent cycle stability (capacity retention of 167.8 mAh g−1 after 2350 cycles under 2.0 A g−1), placing it among the top performers in reported TMD‐based PIB anodes. In situ XRD and Raman measurements reveal the intercalation‐based mechanism in NbSe2 NSs/G and the introduction of graphene can alleviate the severe volume change, making it possess superior rate performance and cycle stability Prominently, full‐cell PIBs employing NbSe2 NSs/G anodes demonstrate remarkable rate capability, and achieve a high energy density of 103.0 Wh kg−1 and a high power density of 1140.6 W kg−1. [ABSTRACT FROM AUTHOR]

The shape of nanochannels plays a crucial role in the ion selectivity and overall performance of reverse electrodialysis (RED) systems. However, current research on two-dimensional nanochannel shapes is largely limited to a few fixed asymmetric forms. This study explores the impact of randomly shaped nanochannels using dimensionless methods, controlling their randomness by varying their length and shape amplitude. The research systematically compares how alterations in the nanochannel length and shape amplitude influence various system performance parameters. Our findings indicate that increasing the nanochannel length can significantly enhance the system performance. While drastic changes in the nanochannel shape amplitude positively affect the system performance, the most significant improvements arise from the interplay between the nanochannel length and shape amplitude. This compounding effect creates a local optimum, resulting in peak system performance. Within the range of dimensionless lengths from 0 to 30, the system reaches its optimal performance at a dimensionless length of approximately 25. Additionally, we explored two other influencing factors: the nanochannel surface charge density and the concentration gradient of the solution across the nanochannel. Optimal performance is observed when the nanochannel has a high surface charge density and a low concentration gradient, particularly with random shapes. This study advances the theoretical understanding of RED systems in two-dimensional nanochannels, guiding research towards practical operational conditions. [ABSTRACT FROM AUTHOR]

Background and Aims Emerging evidence has raised an obesity paradox in observational studies of body mass index (BMI) and health among the oldest-old (aged ≥80 years), as an inverse relationship of BMI with mortality was reported. This study was to investigate the causal associations of BMI, waist circumference (WC), or both with mortality in the oldest-old people in China. Methods A total of 5306 community-based oldest-old (mean age 90.6 years) were enrolled in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) between 1998 and 2018. Genetic risk scores were constructed from 58 single-nucleotide polymorphisms (SNPs) associated with BMI and 49 SNPs associated with WC to subsequently derive causal estimates for Mendelian randomization (MR) models. One-sample linear MR along with non-linear MR analyses were performed to explore the associations of genetically predicted BMI, WC, and their joint effect with all-cause mortality, cardiovascular disease (CVD) mortality, and non-CVD mortality. Results During 24 337 person-years of follow-up, 3766 deaths were documented. In observational analyses, higher BMI and WC were both associated with decreased mortality risk [hazard ratio (HR) 0.963, 95% confidence interval (CI) 0.955–0.971 for a 1-kg/m2 increment of BMI and HR 0.971 (95% CI 0.950–0.993) for each 5 cm increase of WC]. Linear MR models indicated that each 1 kg/m2 increase in genetically predicted BMI was monotonically associated with a 4.5% decrease in all-cause mortality risk [HR 0.955 (95% CI 0.928–0.983)]. Non-linear curves showed the lowest mortality risk at the BMI of around 28.0 kg/m2, suggesting that optimal BMI for the oldest-old may be around overweight or mild obesity. Positive monotonic causal associations were observed between WC and all-cause mortality [HR 1.108 (95% CI 1.036–1.185) per 5 cm increase], CVD mortality [HR 1.193 (95% CI 1.064–1.337)], and non-CVD mortality [HR 1.110 (95% CI 1.016–1.212)]. The joint effect analyses indicated that the lowest risk was observed among those with higher BMI and lower WC. Conclusions Among the oldest-old, opposite causal associations of BMI and WC with mortality were observed, and a body figure with higher BMI and lower WC could substantially decrease the mortality risk. Guidelines for the weight management should be cautiously designed and implemented among the oldest-old people, considering distinct roles of BMI and WC. [ABSTRACT FROM AUTHOR]

Objective: The associations between plasma vitamin B12 level and anemia under different dietary patterns in elderly Chinese people are poorly understood. We aimed to examine the associations between plasma vitamin B12 levels and anemia under different dietary patterns in adults aged 65 years and older in nine longevity areas in China. Methods: A total of 2405 older adults completed a food frequency questionnaire at the same time as a face-to-face interview. The dietary diversity score (DDS) was assessed based on the food frequency questionnaire, with the low DDS group referring to participants with a DDS score ≤ 4 points. Vitamin B12 levels were divided into two groups of high (>295 pg/mL) and low (≤ 295 pg/mL) with the median used as the cut-off point. Sub-analyses were also performed on older adults divided into tertiles of vitamin B12 levels: low (< 277 pg/mL), medium (277–375 pg/mL) and high (> 375 pg/mL) to study the association of these levels with anemia. Results: Six hundred ninety-five (28.89%) of these people were diagnosed with anemia and had a mean age of 89.3 years. Higher vitamin B12 levels were associated with a decreased risk of anemia (multi-adjusted OR, 0.59, [95% CI, 0.45 ~ 0.77] P < 0.001) in older adults with a low DDS, whereas no significant association between vitamin B12 levels and anemia was found in older adults with a high DDS in a full-model after adjustment for various confounding factors (multi-adjusted OR, 0.88, [95% CI, 0.65 ~ 1.19], P = 0.41). Conclusion: The relationship between vitamin B12 levels and the prevalence of anemia was significant only when the level of dietary diversity in the older adults was relatively low. The dietary structure of the population should be taken into consideration in combination in order to effectively improve anemia status by supplementing vitamin B12. [ABSTRACT FROM AUTHOR]