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SIRT6 is a key member of the mammalian sirtuin family of conserved nicotinamide adenine dinucleotide (NAD+)‐dependent deacetylases. Previous studies have shown that SIRT6 can regulate metabolism, DNA damage repair and aging. Ovarian aging process usually share similar mechanisms with general aging, which is characterized by decreases in both numbers of ovarian follicles and the quality of oocytes. It is reported that the expression level of SIRT6 was significantly decreased in the ovaries of aged mice, and the level of SIRT6 was positively correlated with ovarian reserve, indicating that SIRT6 may be potential markers of ovarian aging. However, its biological roles in follicular development are still unclear. Here, we explored the effect of SIRT6 on follicular development and found that ovarian development was interrupted in SIRT6 knockout (KO) mice, leading to disruptions of puberty and the estrus cycle, significant decreases in numbers of secondary and antral follicles, and decreased collagen in the ovarian stroma. Plod1, a lysyl hydroxylase that is vital for collagen crosslinking and deposition, was decreased at both the mRNA and protein levels in SIRT6‐deficient ovaries and granulosa cells (GCs). Additionally, we found abnormal estrogen levels in both SIRT6 KO mice and SIRT6 KD GCs, accompanied by decreases in the levels of the estrogen biosynthesis genes Cyp11a1, Cyp19a1, Mgarp, and increases in the levels of TNF‐α and NF‐κB. These results confirmed the effect of SIRT6 on follicular development and revealed a possible molecular mechanism for SIRT6 involvement in follicular development via effects on estrogen biosynthesis and collagen formation. Our study confirmed that SIRT6 was involved in follicular development in mice in a way that SIRT6 deficiency downregulated the expression level of estrogen biosynthesis related genes Cyp11a1, Cyp19a1, Mgarp, and the expression level of collagen formation gene Plod1. And this molecular mechanism caused ovarian hypoplasia, which is characterized by disruptions of puberty and the estrus cycle, significant decreases in numbers of secondary and antral follicles, as well as decreased collagen in the ovarian stroma. [ABSTRACT FROM AUTHOR]

The importance of predicting the diffusion coefficient to describe the diffusion process in glassy polymers is obvious. However, most of the direct measurements of diffusion coefficients are time‐consuming, expensive and system intrusive. Here, we report a facile method to measure the apparent diffusion constant on the cross‐section of thin PVA film with a device that is structured with a thin conductive film. The results can employ diffusion and the solution conductivity theory well. The diffusion time and the conductivity of the device are determined by the process of solution passing through the cross‐section of thin PVA film and reaching the conductive substrate. The data detected the apparent diffusion constant in diffusion and the concentration gradient of the solution on the interface between the PVA film and conductive film. This device provides a simple, rapid, and effective way to study the apparent diffusion constant in PVA film. It holds great potential in predicting the diffusion process of a thin glassy polymer film. [ABSTRACT FROM AUTHOR]

The development and application of information and communication technology in distribution networks (DNs) brings new and abundant measurement data, and this has inspired many solutions for the monitoring, protection and control application of DNs. Against this background, a novel fault location method based on structure‐preserving state estimation (SPSE) is proposed to enhance the fault location performance of DNs. A SPSE model that reflects the change in the network topology during fault incidents is constructed by combining classical measurement equations with newly introduced topology equations. Then, a unified faulted structure‐preserving topology model that eliminates the influence of uncertain fault location point is presented. According to the calculated measurement residual indices and the equivalent fault current for each state estimation (SE) section, the location of the fault is determined. Considering different fault scenarios in a distribution network, the performance of the proposed method is tested by using MATLAB software. Moreover, the factors of sensor accuracy, the bad data and data missing issues are considered. The test results demonstrate that the method can precisely determine the real location of fault and has good robustness to possible data anomalies. [ABSTRACT FROM AUTHOR]

Summary: In mammals, DNA methylation is associated with aging. However, age‐related DNA methylation changes during phase transitions largely remain unstudied in plants. Moso bamboo (Phyllostachys edulis) requires a very long time to transition from the vegetative to the floral phase. To comprehensively investigate the association of DNA methylation with aging, we present here single‐base‐resolution DNA methylation profiles using both high‐throughput bisulfite sequencing and single‐molecule nanopore‐based DNA sequencing, covering the long period of vegetative growth and transition to flowering in moso bamboo. We discovered that CHH methylation gradually accumulates from vegetative to reproductive growth in a time‐dependent fashion. Differentially methylated regions, correlating with chronological aging, occurred preferentially at both transcription start sites and transcription termination sites. Genes with CG methylation changes showed an enrichment of Gene Ontology (GO) categories in 'vegetative to reproductive phase transition of meristem'. Combining methylation data with mRNA sequencing revealed that DNA methylation in promoters, introns and exons may have different roles in regulating gene expression. Finally, circular RNA (circRNA) sequencing revealed that the flanking introns of circRNAs are hypermethylated and enriched in long terminal repeat (LTR) retrotransposons. Together, the observations in this study provide insights into the dynamic DNA methylation and circRNA landscapes, correlating with chronological age, which paves the way to study further the impact of epigenetic factors on flowering in moso bamboo. Significance Statement: Moso bamboo requires a very long time to transition from the vegetative to the floral phase. Here, we found that the DNA methylation level varies with chronological age in moso bamboo. This study also provides insights into flanking introns of circRNAs, which are hypermethylated and enriched in LTR retrotransposons. [ABSTRACT FROM AUTHOR]

Considering a large number of stochastic scenarios when optimising the flexible resource capacity for isolated microgrids not only improves the accuracy and credibility of the results but also enables the use of probabilistic statistical methods to obtain a scheme that balances robustness and costs. However, the consideration of massive scenarios can drastically lower the computational efficiency, and there is a lack of research on configuration methods that can result in a compromise. In this study, a characteristic‐matching method is proposed to enhance the computational efficiency of optimisation, and a statistics‐based prism filtering method is designed to obtain the compromise scheme for use by decision‐makers. Specifically, the massive scenario set is divided into four subsets. The characteristic‐matching method is proposed to obtain a near‐optimal solution, which is used as the initial iteration value to accelerate the computational speed. Then, a characteristic‐matching‐based bi‐level optimisation method is proposed to solve massive scenarios with high computational efficiency. Moreover, a prism filtering method is designed to select a compromise scheme with high economic benefits using scenario coverage, load curtailment, power curtailment and economy indicators. Simulation results verify the effectiveness of the proposed models and methods. [ABSTRACT FROM AUTHOR]

The line start permanent magnet synchronous motor (LSPMSM) can be used for direct‐on‐line (DOL) starting, so it is easily affected by voltage unbalance. Based on the finite element method (FEM) and analytical method, the influence of voltage unbalance on the steady‐state performance of LSPMSM is studied in this paper. A two‐dimensional finite element model is built, and the armature current, losses and torque ripple as a function of the phase voltage unbalance rate (PVUR) are obtained. The influence mechanism of voltage unbalance on the steady‐state performance of a motor is demonstrated. Finally, a prototype of LSPMSM is manufactured and tested. By comparing the experimental data with the simulation data, the accuracy of the calculation model is verified, and the correctness of the research is proved. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]