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China Geology 2022年第4期5卷 771-773页

作者： Xiang Qin Xuan-hua chen Zhao-gang Shao Yi-ping Zhang Yong-chao Wang Chinese Academy of Geological Sciences China Geological SurveyMinistry of Natural ResourcesBeijing 100037China

1.Objectives In the Indosinian duration,series of Gondwana-related plates pieced together and formed the geological sketch of China for the first time,i.***.the Yangtze,Sino Korean,Tarim plates,and other sub-plates that had been isolated for a long time.Subduction and collision among the Tarim,Qaidam,and Qiangtang blocks in Triassic,as well as the closure of the Paleo-Tethys Ocean,reactivated Late Paleozoic suture zones in the Tianshan orogen region(Hendrix MS et al.,1992).

关键词： Tianshan Triassic strata

基于改进P-f下垂方程的构网型逆变器主动孤岛检测方法

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电工技术 2024年第2期 9-12页

作者：魏友金蒋旺黄顺权江晨陈凯龙华电(华安)供电有限公司福建漳州363899 南京国电南自电网自动化有限公司江苏南京211106

目前大多数孤岛检测算法是针对跟网型逆变器设计的,对基于下垂控制的构网型逆变器并不适用。被动孤岛检测方法在基于下垂控制的系统中,由于下垂系数设计偏小且系统本身存在负反馈特性,因此只有在负荷功率与逆变器输出功率严重不匹配的... 详细信息

目前大多数孤岛检测算法是针对跟网型逆变器设计的,对基于下垂控制的构网型逆变器并不适用。被动孤岛检测方法在基于下垂控制的系统中,由于下垂系数设计偏小且系统本身存在负反馈特性,因此只有在负荷功率与逆变器输出功率严重不匹配的工况下才能检测到孤岛,检测盲区大。常规主动孤岛检测方法需要加入扰动来实现孤岛检测,对系统的电能质量影响较大。为此,提出一种基于改进P-f下垂方程的主动孤岛检测方法。在并网稳定之后加入电压偏差增量,一旦大电网端瞬间失电,就通过新的下垂方程计算此刻公共耦合点的频率,由于该量瞬间发生很大的波动且很快超过限定值,因此孤岛检测可以迅速完成,并且对系统的电能质量影响较小。最后在MATLAB/Simulink中进行不同工况的仿真验证,并且基于TMS320F28379D与Speedgoat实时仿真目标机进行实物验证。

关键词：微电网构网型逆变器主动孤岛检测下垂控制电压偏差量

AKT-modified autologous intracoronary mesenchymal stem cells prevent remodeling and repair in swine infarcted myocardium

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Chinese Medical Journal 2010年第13期123卷 1702-1708页

作者： YU Yun-sheng SHEN Zhen-ya YE Wen-xue huaNG Hao-yue hua Fei chen Yi-huan chen Ke LAO Wei-jie TAO Li Department of Cardiovascular Surgery First Affiliated Hospital of Soochow University Suzhou Jiangsu 215006 China

Background Transplantation of adult bone marrow-derived mesenchymal stem cells （MSCs） has been proposed as a strategy for cardiac repair following myocardial damage. However cell transplantation strategies to replace lost myocardium are limited by the inability to deliver large numbers of cells that resist peritransplantation graft cell death. Accordingly, we set out to isolate and expand adult swine bone marrow-derived MSCs, and to engineer these cells to overexpress AKT1 （protein kinase B）, to test the hypothesis that AKTl-engineered MSCs are more resistant to apoptosis and can enhance cardiac repair after transplantation into the ischemic swine heart. Methods The CDS （regulation domain of AKT1） AKTI-cDNA fragment was amplified, and MSCs were transfected following synthesis with a pCDH1-AKT1 shuttling plasmid. Western blotting analysis and real-time reverse transcription-polymerase chain reaction （RT-PCR） was performed. Myocardial infarction （MI） models were constructed in Meishan pigs, and cardiac function was evaluated by magnetic resonance imaging （MRI） measurements and echocardiography 4 weeks later. All pigs were assigned to four groups： control （A）, DMEM （B）, MSC （C）, and AKT-transfected （D）. MSCs were transfected with the AKT1 gene, and autologous BrdU-labeled stem cells （1 × 10^7/5 ml） were injected into left anterior descending coronary atery （LAD） of the infarct heart in groups C and D. In group B, DMEM was injected using the same approach. In group A, there was no injection following LAD occlusion. After 4 weeks, cardiac function and regional perfusion measurements were repeated by MRI and echocardiography, and histological characteristics of the hearts were assessed. Connecxin-43 （CX-43）, BrdU, and von Willebrand factor （VWF） immunoreactivity was tested using enzyme linked immunosorbent assay （ELISA）. Vascular endothelial growth factor （VEGF）, transforming growth factor-β1 （TGF-β1） were analyzed at the same time. Results AKTI-cDNA was cloned into pCDH1-MCS1-EFI-copGFP and the sequence was confirmed.

关键词： gene therapy mesenchymal stem cell autologous implant myocardial infarction

Expression level of miR-155 in peripheral blood

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Asian Pacific Journal of Tropical Medicine 2015年第3期8卷 214-219页

作者： Yu-Hui Zhang Liang-hua Xia Jia-Mei Jin Ming Zong Ming chen Bo Zhang Department of Ultrasound East Hospital Affiliated to Medicine SchoolTongji University Department of Ultrasound Shanghai Huadong Hospital Affiliated to Medicine School.Fudan University

Objective:To investigate the relationship between the expression level of miR-155 and the severity of coronary lesion,and explore the action mechanism.Methods:Peripheral blood mononuclear cells(PBMC) were isolated form blood simple from patients with acute myocardial infarction(AMI),unstable angina(UAP).stable angina(SAP) and chesl pain syndrome(CPS).RT-PCR was performed to analysis the expression level of miR-155 in peripheral blood mononuclear cells,plasma and RAW264.7 macrophagocyte.MTT was used to analyze the cell viability of OxLDL treated RAW264.7 macrophagocyte.Results:The expression level of miR-155 in blood sample from coronary heart disease patients was much lower than in the blood sample of non-coronary heart disease(P<0.05).The level of miR-155 in PBMCs was much higher in the blood sample from CPS group than the other three group,and the level of miR-155 in plasma was higher in the CPS group than in the UAP and the AMI group,the difference was statistically significant(P<0.05).The expression level of miR-155 in PBMCs is positively associated with the level in the plasma(r=0.861,P=0.000).OxLDL can induce the expression of miR-155 in RAW264.7 macrophagocyte.decrease the cell viability of RAW264.7 macrophagocyte.and with the concentration and the treatment time of OxLDL increased,the effort become more obvious.The inhibition effort of OxLDL to RAW264.7macrophagocyte with high miR-155 expression is much lower than the control group,and it is statistically significant after treated for 12.24 and 48 h.Conclusions:miR-155 plays a protective role in the progression of atherosclerosis,and it may be achieved by reducing the apoptosis effort of OxLDL to RAW264.7 macrophagocyte.

关键词： miR-155 Coronary heart disease RAW264.7 macrophagocyte

Fabrication of hierarchical polycaprolactone/gel scaffolds via combined 3D bioprinting and electrospinning for tissue engineering

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Advances in Manufacturing 2014年第3期2卷 231-238页

作者： Yong-Ze Yu Lu-Lu Zheng Hai-Ping chen Wei-hua chen Qing-Xi Hu Rapid Manufacturing Engineering Center Shanghai University

It is a severe challenge to construct 3D scaf- folds which hold controllable pore structure and similar morphology of the natural extracellular matrix （ECM）. In this study, a compound technology is proposed by com- bining the 3D bioprinting and electrospinning process to fabricate 3D scaffolds, which are composed by orthogonal array gel microfibers in a grid-like arrangement and inter- calated by a nonwoven structure with randomly distributed polycaprolactone （PCL） nanofibers. Human adipose- derived stem cells （hASCs） are seeded on the hierarchical scaffold and cultured 21 d for in vitro study. The results of cells culturing show that the microfibers structure with controlled pores can allow the easy entrance of cells and the efficient diffusion of nutrients, and the nanofiber webs layered in the scaffold can significantly improve initial cell attachment and proliferation. The present work demon- strates that the hierarchical PCL/gel scaffolds consisting of controllable 3D architecture with interconnected pores and biomimetic nanofiber structures resembling the ECM can be designed and fabricated by the combination of 3D bioprinting and electrospinning to improve biological per- formance in tissue engineering applications.

关键词： Hierarchical scaffold 3D bioprinting Electrospinning Tissue engineering

Tribological properties in seawater for Ti/TiCN coatings on Ti6Al4V alloy by arc ion plating with different carbon contents

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Rare Metals 2017年第11期36卷 858-864页

作者： Jin-Long Li Gang-Yi Cai hua-Sheng Zhong Yong-Xin Wang Jian-Min chen Key Laboratory of Marine Materials and Application Technologies Zhejiang Key Laboratory of Marine Materials and Protection Technologies Ningbo Institute of Materials Technologies and Engineering Chinese Academy of Sciences School of Mechanical and Electrical Engineering Henan University of Technology

TiCN coatings incorporated with Ti buffer layer were deposited on Ti6A14V alloy by arc ion plating. The carbon content in TiCN coatings was varied by controlling flow rates of C2H2 in reactive gas. The Ti/TiCN coatings have a typical structure of columnar crystal with a total thickness of about 2 pro. The elements of Ti, C and N are present as TiN and TiC in TiCN coatings. A little free carbon appears with carbon content increasing in TiCN coatings. For the TiCN coatings, the hardness, friction coefficient and wear rate decrease with the increase in carbon content. In seawater, both friction coefficient and wear rate have an obvious decrease at lower carbon content compared with those in atmosphere. However, the friction coefficient and wear rate only have a slight decrease, while the carbon content reaches or exceeds 10 at% in Ti/TiCN coatings.

关键词： Ti/TiCN coatings Arc ion plating Hardness Seawater Wear

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环氧基复合吸波涂层的制备与性能研究

表面技术 2022年第4期51卷 325-334页

作者：王顺顺张喆王霏张际亮颜丙功顾永华江开勇华侨大学福建省特种能场制造重点实验室福建厦门361021 华侨大学厦门市数字化视觉测量重点实验室福建厦门361021

目的制备综合吸波性能良好的复合吸波涂层。方法选择炭黑和羰基铁粉进行机械混合,作为吸波剂加入到环氧树脂中进行吸波材料制备,利用扫描电子显微镜对炭黑和羰基铁粉分别进行微观形貌的观察。利用矢量网络分析仪在2~18 GHz内测试其电磁... 详细信息

目的制备综合吸波性能良好的复合吸波涂层。方法选择炭黑和羰基铁粉进行机械混合,作为吸波剂加入到环氧树脂中进行吸波材料制备,利用扫描电子显微镜对炭黑和羰基铁粉分别进行微观形貌的观察。利用矢量网络分析仪在2~18 GHz内测试其电磁性能,研究炭黑和羰基铁粉含量及涂层厚度对吸波性能的影响规律。结果通过观察微观形貌发现,炭黑颗粒较小,出现团聚和粘附性现象,羰基铁粉颗粒呈球状,表面光滑,分散性好。复合后的材料混合较均匀,羰基铁粉分散在基体中,与炭黑团配合能够提高材料的吸波性能。纯炭黑的吸波频带较窄,纯羰基铁粉的频带主要集中在中高频段,而复合后的吸波频段较宽,有着良好的吸波性能。炭黑质量分数为4%,羰基铁粉质量分数为250%,厚度为2 mm时,吸波涂层在9~18 GHz的微波吸收率超过90%,且反射损耗峰值达到近–45 dB。结论炭黑和羰基铁粉复合后,吸波材料的吸波频带更宽,效果更好,解决了单一吸波剂涂层存在的吸波频带窄和集中于高频段的问题。通过调节涂层厚度,可以使材料在相对应的波段获得更好的吸波性能,从而得到更广泛的应用。

关键词：吸波涂层炭黑羰基铁粉复介电常数复磁导率吸波性能

Prevalence and risk factors for Barrett’s esophagus in Taiwan

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World Journal of Gastroenterology 2019年第25期25卷 3231-3241页

作者： Yan-hua chen Hsien-Chung Yu Kung-Hung Lin Huey-Shyan Lin Ping-I Hsu Division of Gastroenterology and Hepatology Department of Internal MedicineKaohsiung Veterans General HospitalKaohsiung 81362Taiwan Health Evaluation Center Kaohsiung Veterans General HospitalKaohsiung 81362Taiwan Department of Nursing Meiho UniversityNeipu TownshipPingtung County 91202Taiwan Institute of Health Care Management Department of Business ManagementNational Sun Yat-Sen UniversityKaohsiung 80424Taiwan Department of Health-Business Administration Fooyin UniversityKaohsiung 83102Taiwan National Yang Ming University Taipei 12221Taiwan

BACKGROUND Barrett’s esophagus(BE)is a pre-malignant condition associated with the development of esophageal adenocarcinoma.The prevalence of BE in the general populations of Asian countries ranges from 0.06%to 1%.However,with lifestyle changes in Asian countries and adoption of western customs,the prevalence of BE might have increased.AIM To determine the current prevalence of BE in Taiwan,and to investigate risk factors predicting the presence of BE.METHODS This retrospective study was conducted at the Health Evaluation Center of Kaohsiung Veterans General Hospital in Taiwan.Between January 2015 and December 2015,3385 subjects undergoing routine esophagogastroduodenoscopy examinations as part of a health check-up at the Health Evaluation Center were included.Patient characteristics and endoscopic findings were carefully reviewed.Lesions with endoscopic findings consistent with BE awaiting histological evaluation were judged as endoscopically suspected esophageal metaplasia(ESEM).BE was defined based on extension of the columnar epithelium≥1 cm above the gastroesophageal junction and was confirmed based on the presence of specialized intestinal metaplasia(IM)in the metaplastic esophageal epithelium.Clinical factors of subjects with BE and subjects without BE were compared,and the risk factors predicting BE were analyzed.RESULTS A total of 3385 subjects(mean age,51.29±11.42 years;57.1%male)were included in the study,and 89 among them were confirmed to have IM and presence of goblet cells via biopsy examination.The majority of these individuals were classified as short segment BE(n=85).The overall prevalence of BE was 2.6%.Multivariate analysis disclosed that old age[odds ratio(OR)=1.033;95%confidence interval(CI):1.012-1.055;P=0.002],male gender(OR=2.106;95%CI:1.145-3.872;P=0.017),ingestion of tea(OR=1.695;95%CI:1.043-2.754;P=0.033),and presence of hiatal hernia(OR=3.037;95%CI:1.765-5.225;P<0.001)were significant risk factors predicting BE.The independent risk factor for the presence of IM in ESEM lesions was old

关键词： Barrett’s esophagus Prevalence Risk factors Intestinal metaplasia Taiwan

Genome size evolution of the extant lycophytes and ferns

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Plant Diversity 2022年第2期44卷 141-152页

作者： Fa-Guo Wang Ai-hua Wang cheng-Ke Bai Dong-Mei Jin Li-Yun Nie AJ Harris Le Che Juan-JuanWang Shi-Yu Li Lei Xu Hui Shen Yu-Feng Gu Hui Shang Lei Duan Xian-Chun Zhang Hong-Feng chen Yue-Hong Yan Key Laboratory of Plant Resources Conservation and Sustainable Utilization Guangdong Provincial Key Laboratory of Applied BotanySouth China Botanical GardenChinese Academy of SciencesGuangzhou510650China College of Life Sciences Shaanxi Normal UniversityXi'an710062China Eastern China Conservation Centre for Wild Endangered Plant Resources Shanghai Chenshan Botanical GardenShanghai201602China Key Laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of EducationNanning Normal UniversityNanning530001China Department of Biology Oberlin CollegeOberlinOH44074USA State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing100093China Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization the National Orchid Conservation Center of China and the Orchid Conservation&Research Center of Shenzhen518114ShenzhenChina Life Science and Technology College Harbin Normal UniversityHarbin150025China

Ferns and lycophytes have remarkably large genomes.However,little is known about how their genome size evolved in fern lineages.To explore the origins and evolution of chromosome numbers and genome size in ferns,we used flow cytometry to measure the genomes of 240 species(255 samples)of extant ferns and lycophytes comprising 27 families and 72 genera,of which 228 species(242 samples)represent new reports.We analyzed correlations among genome size,spore size,chromosomal features,phylogeny,and habitat type preference within a phylogenetic framework.We also applied ANOVA and multinomial logistic regression analysis to preference of habitat type and genome size.Using the phylogeny,we conducted ancestral character reconstruction for habitat types and tested whether genome size changes simultaneously with shifts in habitat preference.We found that 2 C values had weak phylogenetic signal,whereas the base number of chromosomes(x)had a strong phylogenetic signal.Furthermore,our analyses revealed a positive correlation between genome size and chromosome traits,indicating that the base number of chromosomes(x),chromosome size,and polyploidization may be primary contributors to genome expansion in ferns and lycophytes.Genome sizes in different habitat types varied significantly and were significantly correlated with habitat types;specifically,multinomial logistic regression indicated that species with larger 2 C values were more likely to be epiphytes.Terrestrial habitat is inferred to be ancestral for both extant ferns and lycophytes,whereas transitions to other habitat types occurred as the major clades emerged.Shifts in habitat types appear be followed by periods of genomic stability.Based on these results,we inferred that habitat type changes and multiple whole-genome duplications have contributed to the formation of large genomes of ferns and their allies during their evolutionary history.

关键词： Genome size Ferns Chromosome numbers Habitat type Whole-genome duplications Evolution

DnaJA4 is involved in responses to hyperthermia by regulating the expression of F-actin in HaCaT cells

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Chinese Medical Journal 2021年第4期134卷 456-462页

作者： Rui-Jiao Liu Xue-Li Niu Jin-Ping Yuan Hong-Duo chen Xing-hua Gao Rui-Qun Qi Department of Dermatology The First Hospital of China Medical UniversityShenyangLiaoning 110001China National Health Commission Key Laboratory of Immunodermatology(China Medical University) ShenyangLiaoning 110001China Key Laboratory of Immunodermatology(China Medical University) Ministry of EducationShenyangLiaoning 110001China National and Local Joint Engineering Research Center of Immunodermatological Theranostics ShenyangLiaoning 110001China.

Background:Hyperthermia in combination with DnaJA4-knockout(KO)obviously affects the anti-viral immunity of HaCaT cells.The mechanisms of this process are not yet fully explored.However,it is known that DnaJA4 interacts with actin cytoskeleton after hyperthermia.Our aim was to investigate the effects of DnaJA4 on F-actin in HaCaT cells following hyperthermia.Methods:Wild-type(WT)and DnaJA4-KO HaCaT cells were isolated at either 37°C(unheated)or 44°C(hyperthermia)for 30 min followed by testing under conditions of 37°C and assessing at 6,12,and 24 h after hyperthermia.The cytoskeleton was observed with immunofluorescence.Flow cytometry and Western blotting were used to detect the expression of F-actin and relevant pathway protein.Results:DnaJA4-KO and hyperthermia changed the cytoskeleton morphology of HaCaT cells.F-actin expression levels were elevated in DnaJA4-KO cells compared with WT cells(6364.33±989.10 vs.4272.67±918.50,P<0.05).In response to hyperthermia,F-actin expression levels of both WT and DnaJA4-KO cells showed a tendency to decrease followed by an obvious recovery after hyperthermia(WT cells:unheated vs.6 h after hyperthermia or 24 h after hyperthermia:0.34±0.02 vs.0.24±0.01,0.31±0.01,P<0.001,P<0.05;DnaJA4-KO cells:unheated vs.6 h after hyperthermia or 24 h after hyperthermia:0.44±0.01 vs.0.30±0.01,0.51±0.02,P<0.001,P<0.01).WT cells restored to baseline levels observed in the unheated condition,while DnaJA4-KO cells exceeded baseline levels in the recovery.As the upstream factors of F-actin,a similar profile in rho-associated serine/threonine kinase 1(ROCK 1)and RhoA expressions was observed after hyperthermia.While E-cadherin expression was decreased in response to hyperthermia,it was increased in DnaJA4-KO cells compared with WT cells.Conclusions:Hyperthermia affects the expression levels of F-actin in HaCaT cells.DnaJA4 knockout increases the expression of F-actin in HaCaT cells after hyperthermia.DnaJA4 regulates the expressions of F-actin and the related pathway proteins in response to hyperther

关键词： Hyperthermia DnaJA4 F-actin HaCaT