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计及锁相环非线性特性的跟网型逆变器暂态稳定性分析

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电工电能新技术 2024年第7期43卷 12-22页

作者：王素娥李康郝鹏飞刘煜帆崔开源陈景文陕西科技大学电气与控制工程学院陕西西安710021

锁相环作为跟网型逆变器实现相位同步的关键环节,由于其本身所固有的非线性特性,在弱电网情况下,传统小信号模型可能存在不能准确预测锁相环暂态稳定性的问题。为保证受扰后锁相环的稳定运行,提出了一种基于非线性数学模型的稳定性分析... 详细信息

锁相环作为跟网型逆变器实现相位同步的关键环节,由于其本身所固有的非线性特性,在弱电网情况下,传统小信号模型可能存在不能准确预测锁相环暂态稳定性的问题。为保证受扰后锁相环的稳定运行,提出了一种基于非线性数学模型的稳定性分析方法。首先,根据锁相环工作原理,建立其二阶非线性微分方程,通过相平面法对锁相环输出特性进行定性分析,评估不同参数对锁相环暂态特性的影响;然后,基于等面积法则分析锁相环暂态失稳机理,鉴于传统等面积法则可能导致稳定性的误判,采用非线性动力学多尺度法对锁相环受扰后的暂态时域表达式进行求解,明确锁相环暂态稳定边界;最后,通过Matlab仿真和RT⁃LAB半实物平台验证了所得解析解和锁相环暂态稳定域的准确性,为弱电网条件下锁相环控制参数及电路参数选取提供一定参考。

关键词：跟网型逆变器锁相环非线性弱电网暂态稳定性多尺度法

Climate change impacts on environmental geosciences: Introduction

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Geoscience Frontiers 2019年第2期10卷 361-362页

作者： Lawal Billa sue Walker School of Environmental and Geographical Sciences The University of NottinghamMalaysia Campus Department of Soil Crop and Climate ScienceUniversity of the Free StateBloemfontein Campus

Climate change and its impacts have become topical issues of global news,scientific research and *** Geosciences incorporate the various disciplines of geosciences and their multifaceted interactions with *** discussions on the interaction of climate change,geosciences and environment may often be blur,and Schmidt-Thoméet al.(2010)stated that“Often past climate changes that can be deduced from geological records may help in understanding the speed of potential climate change effects,*** quickly have sea levels changed,how drastic has nature reacted to ups and downs in temperature,*** analyses of past events help in giving outlooks on potential changes in our living *** is also of important to understand the magnitude and potential effects of extreme events,such as droughts and floods”.

关键词： Climate change environmental geosciences

Genetic association and epistatic interaction of the interleukin-10 signaling pathway in pediatric inflammatory bowel disease

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World Journal of Gastroenterology 2017年第27期23卷 4897-4909页

作者： Zhenwu Lin Zhong wang John P Hegarty Tony R Lin Yunhua wang sue Deiling Rongling Wu Neal J Thomas Joanna Floros CHILD Research Department of Pediatricsthe Pennsylvania State UniversityCollege of Medicine Department of Radiology University of Pennsylvania Perelman School of Medicine Division of Biostatistics Department of Public Health Sciencethe Pennsylvania State UniversityCollege of Medicine Department of Surgery the Pennsylvania State UniversityCollege of Medicine Department of Obstetrics and Gynecology the Pennsylvania State UniversityCollege of Medicine

To study the genetic association and epistatic interaction of the interleukin (IL)-10 and IL-10/STAT3 pathways in pediatric inflammatory bowel disease (IBD). METHODSA total of 159 pediatric inflammatory IBD patients (Crohn’s disease, n = 136; ulcerative colitis, n = 23) and 129 matched controls were studied for genetic association of selected single nucleotide polymorphisms (SNPs) of the IL-10 gene and the genes IL10RA, IL10RB, STAT3, and HO1, from the IL-10/STAT3 signaling pathway. As interactions between SNPs from different loci may significantly affect the associated risk for disease, additive (a) and dominant (d) modeling of SNP interactions was also performed to examine high-order epistasis between combinations of the individual SNPs. RESULTSThe results showed that IL-10 rs304496 was associated with pediatric IBD (P = 0.022), but no association was found for two other IL-10 SNPs, rs1800872 and rs2034498, or for SNPs in genes IL10RA, IL10RB, STAT3, and HO1. However, analysis of epistatic interaction among these genes showed significant interactions: (1) between two IL-10 SNPs rs1800872 and rs3024496 (additive-additive P = 0.00015, Bonferroni P value (Bp) = 0.003); (2) between IL-10RB rs2834167 and HO1 rs2071746 (dominant-additive, P = 0.0018, Bp = 0.039); and (3) among IL-10 rs1800872, IL10RB rs2834167, and HO1 rs2071746 (additive-dominant-additive, P = 0.00015, Bp = 0.005), as well as weak interactions among IL-10 rs1800872, IL-10 rs3024496, and IL-10RA (additive-additive-additive, P = 0.003; Bp = 0.099), and among IL10RA, IL10RB, and HO1 genes (additive-dominant-additive, P = 0.008, Bp = 0.287). CONCLUSIONThese results indicate that both the IL-10 gene itself, and through epistatic interaction with genes within the IL-10/STAT3 signaling pathway, contribute to the risk of pediatric IBD.

关键词： Pediatric inflammatory bowel disease Interleukin-10 HO1 Single nucleotide polymorphism IL10-STAT3 pathway Epistatic interaction

Influence of hyperbaric oxygen on the differentiation of hypoxic/ischemic brainderived neural stem cells

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Neural Regeneration Research 2009年第7期4卷 492-496页

作者： Zhengrong Peng sue wang Pingtian Xiao Department of Hyperbaric Oxygen Xiangya Hospital Central South University Changsha 410008 Hunan Province China

BACKGROUND： It has been previously shown that hyperbaric oxygen may promote proliferation of neural stem cells and reduce death of endogenous neural stem cells （NSCs）. OBJECTIVE： To explore the effects of hyperbaric oxygen on the differentiation of hypoxic/ischemic brain-derived NSCs into neuron-like cells and compare with high-concentration oxygen and high pressure. DESIGN, TIME AND SETTING： An in vitro contrast study, performed at Laboratory of Neurology, Central South University between January and may 2006. MATERIALS： A hyperbaric oxygen chamber （YLC 0.5/1A） was provided by Wuhan Shipping Design Research Institute; mouse anti-rat microtubule-associated protein 2 monoclonal antibody by Jingmei Company, Beijing; mouse anti-rat glial fibrillary acidic protein monoclonal antibody by Neo Markers, USA; mouse anti-rat galactocerebroside monoclonal antibody by Santa Cruz Biotechnology Inc., USA; and goat anti-mouse fluorescein isothiocyanate-labeled secondary antibody by Wuhan Boster Bioengineering Co., Ltd., China. METHODS： Brain-derived NSCs isolated from brain tissues of neonatal Sprague Dawley rats were cloned and passaged, and assigned into five groups： normal control, model, high-concentration oxygen, high pressure, and hyperbaric oxygen groups. Cells in the four groups, excluding the normal control group, were incubated in serum-containing DMEM/F12 culture medium. Hypoxic/ischemic models of NSCs were established in an incubator comprising 93% N2, 5% 002, and 2% 02. Thereafter, cells were continuously cultured as follows： compressed air （0.2 MPa, 1 hour, once a day） in the high pressure group, compressed air ＋ a minimum of 80% 02 in the hyperbaric oxygen group, and a minimum of 80% Q2 in the high-concentration oxygen group. Cells in the normal control and model groups were cultured as normal. MAIN OUTCOME MEASURES： At day 7 after culture, glial fibrillary acidic protein, microtubule-associated protein 2, and galactocerebroside immunofluorescence staining

关键词： hyperbaric oxygen brain-derived neural stem cells differentiation hypoxic/ischemicmodel

Possible high COVID-19 airborne infection risk in deep and poorly ventilated 2D street canyons

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建筑模拟(英文) 2023年第9期16卷 1617-1628页

作者： Vitor Lavor Omduth Coceal sue Grimmond Jian Hang Zhiwen Luo School of the Built Environment University of ReadingReadingUK Department of Meteorology University of ReadingReadingUK School of Atmospheric Sciences Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSun Yat-sen UniversityGuangzhouChina Welsh School of Architecture Cardiff UniversityCardiffUK

Despite the widespread assumption that outdoor environments provide sufficient ventilation and dilution capacity to mitigate the risk of COVID-19 infection,there is little understanding of airborne infection risk in outdoor urban areas with poor *** address this gap,we propose a modified Wells-Riley model based on the purging flow rate(QPFR),by using computational fluid dynamics(CFD)*** model quantifies the outdoor risk in 2D street canyons with different approaching wind speeds,urban heating patterns and aspect ratios(building height to street width).We show that urban morphology plays a critical role in controlling airborne infectious disease transmission in outdoor environments,especially under calm winds;with deep street canyons(aspect ratio>3)having a similar infection risk as typical indoor *** ground and leeward wall heating could reduce the risk,windward heating(e.g.,windward wall~10 K warmer than the ambient air)can increase the infection risk by up to 75%.Our research highlights the importance of considering outdoor infection risk and the critical role of urban morphology in mitigating airborne infection *** identifying and addressing these risks,we can inform measures that may enhance public health and safety,particularly in densely populated urban environments.

关键词： airborne infection risk street canyon urban ventilation wall heating CFD modelling

Examining the practical limits of batch effect-correction algorithms:When should you care about batch effects?

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Journal of Genetics and Genomics 2019年第9期46卷 433-443页

作者： Longjian Zhou Andrew Chi-Hau sue Wilson Wen Bin Goh School of Pharmaceutical Science and Technology Tianjin UniversityTianjin30072China School of Biological Sciences Nanyang Technological University60 Nanyang Drive637551Singapore

Batch effects are technical sources of variation and can confound *** many performance ranking exercises have been conducted to establish the best batch effect-correction algorithm(BECA),we hold the viewpoint that the notion of best is ***,alternative questions beyond the simplistic notion of "best" are also interesting:are BECAs robust against various degrees of confounding and if so,what is the limit?Using two different methods for simulating class(phenotype) and batch effects and taking various representative datasets across both genomics(RNA-Seq) and proteomics platforms,we demonstrate that under situations where sample classes and batch factors are moderately confounded,most BECAs are remarkably robust and only weakly affected by upstream normalization *** observation is consistently supported across the multitude of test *** do have limits:When sample classes and batch factors are strongly confounded,BECA performance declines,with variable performance in precision,recall and also batch *** also report that while conventional normalization methods have minimal impact on batch effect correction,they do not affect downstream statistical feature selection,and in strongly confounded scenarios,may even outperform *** other words,removing batch effects is no guarantee of optimal functional ***,this study suggests that simplistic performance ranking exercises are quite trivial,and all BECAs are compromises in some context or another.

关键词： Batch effects Bioinformatics Feature selection Normalization Statistics

Linking individual attributes and host specialization in brood parasitic cuckoos

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Avian Research 2022年第2期13卷 145-151页

作者： sue-Jeong Jin Hae-Ni Kim Geun-Won Bae Jin-Won Lee Jeong-Chil Yoo Korea Institute of Ornithology Kyung Hee UniversitySeoul02447Republic of Korea Department of Biology Kyung Hee UniversitySeoul02447Republic of Korea

Generalist avian brood parasites vary considerably in their degree of host specialization(e.g.,number of hosts);some parasitize the nests of just a few host species,whereas others exploit more than 100 *** factors,including habitat range,habitat type,and geographic location,have been suggested to account for these ***,inter-specific differences in individual attributes,such as personality and plasticity,have rarely been considered as potential factors of such variation,despite their potential relationship to,for example,range *** cage experiments,we tested the hypothesis that parasitic species exploiting more host species may be more active and *** this end,we quantified behaviors exhibited by two Cuculus cuckoos(Common Cuckoo *** and Oriental Cuckoo ***)that vary greatly in their number of host ***,we evaluated exploratory behavior displayed by birds in the cage,such as the number of movements,head-turning,wing-flapping,and *** Common Cuckoo,which has a higher number of host species,tended to exhibit higher levels of exploratory behaviors than the Oriental *** study showed that the two cuckoo species exhibited different exploratory levels,as predicted by the differences in their number of *** studies regarding the causality between individual attributes and host specialization with improved experimental methodology would greatly enhance our understanding of the role of individual characteristics in the coevolution of avian brood parasites and their hosts.

关键词： Brood parasitism Common Cuckoo Individual attributes Number of hosts Oriental Cuckoo

Perioperative treatment options in resectable pancreatic cancer-how to improve long-term survival

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World Journal of Gastrointestinal Oncology 2016年第3期8卷 248-257页

作者： Marianne Sinn Marcus Bahra Timm Denecke sue Travis Uwe Pelzer Hanno Riess Department of Medical Oncology and Haematology Charité-Universitatsmedizin Berlin Department of General Visceral and Transplantation SurgeryCharité-Universitatsmedizin Berlin Institute of Radiology Charité-Universitatsmedizin Berlin

Surgery remains the only chance of cure for pancreatic cancer, but only 15%-25% of patients present with resectable disease at the time of primary diagnosis. Important goals in clinical research must therefore be to allow early detection with suitable diagnostic procedures, to further broaden operation techniques and to determine the most effective perioperative treatment of either chemotherapy and/or radiation therapy. More extensive operations involving extended pancreatectomy, portal vein resection and pancreatic resection in resectable pancreatic cancer with limited liver metastasis, performed in specialized centers seem to be the surgical procedures with a possible impact on survival. After many years of stagnation in pharmacological clinical research on advanced pancreatic ductal adenocarcinomas(PDAC)- since the approval of gemcitabine in 1997- more effective cytotoxic substances(nab-paclitaxel) and combinations(FOLFIRINOX) are now available for perioperative treatment. Additionally, therapies with a broader mechanism of action are emerging(stroma depletion, immunotherapy, antiinflammation), raising hopes for more effective adjuvant and neoadjuvant treatment concepts, especially in the context of "borderline resectability". Only multidisciplinary approaches including radiology, surgery, medical and radiation oncology as the backbones of the treatment of potentially resectable PDAC may be able to further improve the rate of cure in the future.

关键词： Pancreatic cancer Perioperative treatment Perioperative radiology Chemotherapy

Etiopathogenesis of primary sclerosing cholangitis

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World Journal of Gastroenterology 2008年第21期14卷 3350-3359页

作者： Roger Chapman sue Cullen Department of Gastroen-terology John Radcliffe HospitalHeadingtonOxford OX3 9DUUnited Kingdom

Primary sclerosing cholangitis(PSC) is a chronic cholestatic liver disease of unknown etiology but lymphocytic portal tract infiltration is suggestive of an immune-mediated basis for this *** with inflammatory bowel disease(IBD) especially ulcerative colitis(UC),and with particular autoimmune diseases,as well as the genetic associations further suggest PSC may be an immune-mediated *** immunogenetics of PSC have been the subject of active research and several HLA and non-HLA associated genes have been implicated in the development of the *** derived from the inflamed gut may enter the liver via the enterohepatic circulation to cause hepatic *** may be triggered in genetically susceptible individuals by infections or toxins entering the portal circulation through a permeable colon and hence evoking an abnormal immune response.

关键词： Autoantibody Immunogenetics Biliaryepithelial cells T cell receptor Lymphocytes