Fast electromagnetic transient simulation methods and prospects of high-frequency isolated power electronics transformers

With the increasing uptake of distributed renewable energy and low-carbon technologies (e.g. energy storage and electric vehicle), the conventional AC distribution network is transferring to hybrid AC/DC or pure DC. Power electronics transformers (PETs), also known as solid-state transformers, are multifunctional of integrating distributed generation, regulating bidirectional power flow, and achieving grid interconnection, reactive power compensation, harmonic control, etc. Therefore, PETs can serve as key interfaces for energy conversion in future distribution networks. At present, a number of medium- and low-voltage distribution networks using PETs have commissioned in China, such as the Xiaoertai substation in Zhangbei and Tangjia Bay three-terminal DC distribution network in Zhuhai. The off-line and real-time electromagnetic transient (EMT) simulation studies are of great significance for system-level analysis and prototype development of PETs, which should be investigated timely

Expression of the microRNA-143/145 cluster is decreased in hepatitis B virus-associated hepatocellular carcinoma and may serve as a biomarker for tumorigenesis in patients with chronic hepatitis B

The aims of the present study were to identify the expression profile of microRNA (miR)‑143/145 in hepatitis B virus (HBV)‑associated hepatocellular carcinoma (HCC), explore its association with prognosis and investigate whether the serum miR‑143/145 expression levels may serve as a diagnostic indicator of HBV‑associated HCC. The microRNA (miRNA) chromatin immunoprecipitation dataset was obtained from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus databases, and analyzed using the Wilcoxon signed‑rank test. It was observed that the expression of miR‑143 and miR‑145 was decreased 1.5‑fold in HBV‑associated HCC samples compared with non‑tumor tissue in the TCGA and the GSE22058 datasets (P\u3c0.01). Using the reverse transcription‑quantitative polymerase chain reaction, it was further confirmed that miR‑143/145 and their host gene MIR143HG were downregulated in HBV‑associated HCC tissues compared with corresponding distal non‑tumor tissues. The lower level of miR‑143 and miR‑145 expression was associated with tumor differentiation, and may thus be responsible for a poor prognosis of patients with HBV‑associated HCC. The receiver‑operating characteristic (ROC) curves were used to explore the potential value of miR‑143 and miR‑145 as biomarkers for predicting HBV‑associated HCC tumorigenesis. In serum, miR‑143/145 were identified to be significantly decreased in patients with HBV‑associated HCC compared with negative control patients, and their associated areas under the ROC curves were calculated at 0.813 and 0.852 (P\u3c0.05), with each having a sensitivity and a specificity close to 0.80. These results indicated that the decreased expression of the miR‑143/145 cluster and their host gene MIR143HG in HBV‑associated HCC tissue was associated with prognosis, and each of these miRNAs may serve as a valuable diagnostic biomarker for predicting HBV‑associated HCC tumorigenesis

Fast electromagnetic transient simulation methods and prospects of high-frequency isolated power electronics transformers

With the increasing uptake of distributed renewable energy and low-carbon technologies (e.g. energy storage and electric vehicle), the conventional AC distribution network is transferring to hybrid AC/DC or pure DC. Power electronics transformers (PETs), also known as solid-state transformers, are multifunctional of integrating distributed generation, regulating bidirectional power flow, and achieving grid interconnection, reactive power compensation, harmonic control, etc. Therefore, PETs can serve as key interfaces for energy conversion in future distribution networks. At present, a number of medium- and low-voltage distribution networks using PETs have commissioned in China, such as the Xiaoertai substation in Zhangbei and Tangjia Bay three-terminal DC distribution network in Zhuhai. The off-line and real-time electromagnetic transient (EMT) simulation studies are of great significance for system-level analysis and prototype development of PETs, which should be investigated timely

Effect of the combination of cognitive behavioral therapy and oral paroxetine hydrochloride in patients with post-stroke depression

Purpose: To determine the effects of combined use of cognitive behavioral therapy (CBT) and paroxetine hydrochloride tablets in patients with post-stroke depression (PSD), and its effect on scores on Hamilton Rating Scale for Depression (HAMD) and Stroke Specific Quality of Life Scale (SS-QOL). Methods: Clinical data for 96 patients with PSD who were treated in Dongying Traditional Chinese Hospital, Dongying City, China from June 2018 to June 2019 were retrospectively analyzed. Patients who met the inclusion criteria were divided into treatment group (TG, n = 48) and reference group (RG, n = 48) based on odd and even hospitalization numbers. Both groups received conventional treatment, but RG patients were in addition given clopidogrel, while TG received CBT in combination with paroxetine hydrochloride tablets. Clinical indices were evaluated in both groups before and after treatment. Moreover, therapeutic effects in the two different treatment methods on PSD, as well as on Hamilton Rating Scale for Depression (HAMD) and Stroke Specific Quality of Life Scale (SS-QOL) scores were analyzed. Results: After treatment, TG had lower HAMD score (p < 0.001), lower scores on modified Rankin scale, and few incidences of adverse reactions at 3, 7, 15 and 30 days of treatment (p < 0.05), but higher total clinical effectiveness and mean SS-QOL score (p < 0.05), when compared with RG. Conclusion: Combined use of CBT and oral paroxetine hydrochloride tablets may be a promising strategy for treating depression and enhancing the quality of life of PSD patients, as it greatly improves neurological deficit and prognosis. However, further clinical trials should be carried out prior to introducing it in clinical practice

Geological evaluation of landslide engineering in southern mountainous areas of Henan province

On the basis of analyzing the surrounding environmental conditions and the basic characteristics of potential landslides, the stability of potential landslides was analyzed, calculated, and evaluated. On this basis, the development trend and risk assessment of potential landslides were obtained, and prevention plans were proposed, which have a certain role in preventing landslide disasters

The design of coal mine water disasters prevention and control assistance decision system

Abstract According to actual situation of coal mine water disasters and the expert system research survey, the author has proposed the overall structure of the assistance decision system. The author has established the coal mine water disasters assistance decision platform based on dot NET soft. We has realized the formulation of determination and the preventing and controlling measure of the flood of old hole, roof, floor by using dot Net soft and the CLIPS computer language, combining with database platform established the expert knowledge library and the inference library; has solved the time and the spatial disposition question of the most superior sparse water volume by using the methods of finite element and the linear programming; Moreover aims at these questions of the note thick liquid, searching and draining water, the setup of waterproof rock seam, the forecast of water inflow volume, we has produced the correlation computational methods result and the operation craft.</jats:p

μ-Average n-Widths on the Wiener Space

AbstractIn this paper we consider the μ-average widths of integral operator Tm on the Wiener space C. Some weakly asymptotically exact estimates for the Gelfand width and other widths are obtained