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1Size distribution of chemical elements and their source apportionment in ambient coarse, fine, and ultrafine particles in Shanghai urban summer atmosphere显示文摘Ambient coarse particles (diameter 1.8-10 μm), fine particles (diameter 0.1-1.8 μm), and ultrafine particles (diameter < 0.1 μm) in the atmosphere of the city of Shanghai were sampled during the summer of 2008 (from Aug 27 to Sep 08). Microscopic characterization of the particles was investigated by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM/EDX). Mass concentrations of Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr, and Pb in the size-resolved particles were quantified by using synchrotron radiation X-ray fluorescence (SRXRF). Source apportionment of the chemical elements was analyzed by means of an enrichment factor method. Our results showed that the average mass concentrations of coarse particles, fine particles and ultrafine particles in the summer air were 9.38 ± 2.18, 8.82 ± 3.52, and 2.02 ± 0.41 μg/m3, respectively. The mass percentage of the fine particles accounted for 51.47% in the total mass of PM10, indicating that fine particles are the major component in the Shanghai ambient particles. SEM/EDX results showed that the coarse particles were dominated by minerals, fine particles by soot aggregates and fly ashes, and ultrafine particles by soot particles and unidentified particles. SRXRF results demonstrated that crustal elements were mainly distributed in the coarse particles, while heavy metals were in higher proportions in the fine particles. Source apportionment revealed that Si, K, Ca, Fe, Mn, Rb, and Sr were from crustal sources, and S, Cl, Cu, Zn, As, Se, Br, and Pb from anthropogenic sources. Levels of P, V, Cr, and Ni in particles might be contributed from multi-sources, and need further investigation.Senlin Lu Rui Zhang Zhenkun Yao Fei Yi Jingjing Ren Minghong Wu Man Feng Qingyue Wang 2012Journal of Environmental Sciences2012,24,5:22
2Nat Microbiol:已结首次构建出小鼠肠道微生物组数据库显示文摘小鼠模型通常被广泛用于药理学和医学研究。我们都知道小鼠肠道中的微生物群落通常会对研究结果产生明显的影响,然而目前研究者们并没有获取到关于小鼠肠道中栖息细菌群落的详细信息。近日刊登在国际杂志Nature Microbiology上的一篇研究报告中。德国慕尼黑理工大学的研究者通过研究首次收集到了小鼠肠道中的多种细菌群落。同时研究者还对其进行了分裂、特性分析。最后得到了100种细菌,其中还包括15种迄今为止未知的细菌群落。Lu, Qiulun Yao, Yufeng Hu, Zhenkun Hu, Changqing Song, Qixue Ye, Jian Xu, Chengqi Wang, Annabel Z. Chen, Qiuyun Wang, Qing Kenneth 2016现代生物医学进展2016,16,32:13
3Evaluation of the Trend Uncertainty in Summer Ozone Valley over the Tibetan Plateau in Three Reanalysis Datasets显示文摘Trend uncertainty in the ozone valley over the Tibetan Plateau(OVTP)and the South Asian high(SAH)during1979–2009 in ERA-Interim(interim reanalysis data from the ECMWF),JRA-55(55-yr reanalysis data from the Japan Meteorological Agency),and NCEP-CFSR(Climate Forecast System Reanalysis)datasets was evaluated.The results showed that the NCEP-CFSR OVTP became strong in the summers of 1979–2009,whereas it became weak according to ERA-Interim and JRA-55.Satellite data merged with TOMS(Total Ozone Mapping Spectrometer)and OMI(Ozone Monitoring Instrument)agreed with the OVTP trend of NCEP-CFSR.The OVTP strengthening in NCEP-CFSR may have been caused by SAH intensification,a rising tropopause,and increasing ozone over non-TP(non-Tibetan Plateau)areas(27°–37°N,<75°E and>105°E).Analogously,the OVTP weakening in ERA-Interim and JRA-55 may have been affected by weakening SAH,descending tropopause,and decreasing non-TP ozone.Dong GUO Yucheng SU Xiuji ZHOU Jianjun XU Chunhua SHI Yu LIU Weiliang LI Zhenkun LI 2017Journal of Meteorological Research2017,31,2:13
4Structural basis for blocking PD-l-mediated immune suppression by therapeutic antibody pembrolizumab显示文摘Zhenkun Na Siok Ping Yeo Sakshibeedu R Bharath Matthew W Bowler Esra Ballkci Cheng-I Wang Haiwei Song 2017Cell Research2017,27,1:10
5Green fluorescent protein (GFP) transgenic pig produced by somatic cell nuclear transfer显示文摘Transgenic somatic cell nuclear transfer is a very promising route for producing transgenic farm ani-mals. Research on GFP transgenic pigs can provide useful information for breeding transgenic pigs, human disease models and human organ xenotransplantation. In this study, a liposomal transfection system was screened and transgenic embryos were reconstructed by nuclear transfer of GFP positive cells into enucleated in vitro matured oocytes. The development of reconstructed embryos both in vitro and in vivo was observed, and GFP expression was determined. The results showed that porcine fe-tal-derived fibroblast cells cultured with 4.0 μL/mL liposome and 1.6 μg/mL plasmid DNA for 6 h re-sulted in the highest transfection rate (3.6%). The percentage of GFP reconstructed embryos that de-veloped in vitro to the blastocyst stage was 10%. Of those the GFP positive percentage was 48%. Re-constructed transgenic embryos were transferred to 10 recipients. 5 of them were pregnant, and 3 de-livered 6 cloned piglets in which 4 piglets were transgenic for the GFP as verified by both GFP protein expression and GFP DNA sequence analysis. The percentage of reconstructed embryos that resulted in cloned piglets was 1.0%; while the percentage of piglets that were transgenic was 0.7%. This is the first group of transgenic cloned pigs born in China, marking a great progress in Chinese transgenic cloned pig research.LIU ZhongHua SONG Jun WANG ZhenKun TIAN JiangTian KONG QingRan ZHENG Zhong YIN Zhi GAO Li MA HaiKun SUN Shuang LI YuTian WANG HongBin R S PRATHER 2008Chinese Science Bulletin2008,53,7:8
6A case-control study about the association between vascular endothelial growth inhibitor gene polymorphisms and breast cancer risk in female patients in Northeast China显示文摘Objective: The inhibition of the neovascularization in tumors is a potential therapeutic target of cancer. Vascular endothelial growth inhibitor(VEGI) is a member of the TNF superfamily which has the ability to suppress the formation of new vessels in tumors. In order to study the association between VEGI gene polymorphisms and breast cancer risk, a case-control study was conducted in Chinese Han women in Northeast China.Methods: Our study involved 708 female breast cancer patients and 685 healthy volunteers. Four SNPs of VEGI gene were analyzed through the polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) method. The association between VEGI gene polymorphisms and breast cancer risk was analyzed in our study. The relation between VEGI gene variants and clinical features of breast cancer including lymph node(LN) metastasis, estrogen receptor(ER), progestrogen receptor(PR), tumor protein 53(p53), human epidermal growth factor receptor 2(Her-2) and triple negative(ER-/PR-/Her-2-) status was analyzed as well.Results: We found that the CT genotype and T allele of rs6478106 were more frequent in patients than in controls. There was also a statistical difference in the distribution of C_(rs6478106)G_(rs4263839) haplotype between patients and controls. In addition, SNP rs6478106 and rs4979462 were related with the Her-2 status.Conclusions: Our results suggest that VEGI gene variants may be related to the breast cancer risk and the clinical features of breast cancer in Chinese Han women in Northeast China.Shaoli Han Lei Liu Fengyan Xu Shuang Chen Weiguang Yuan Zhenkun Fu Dalin Li Dianjun Li 2016Chinese Journal of Cancer Research2016,28,4:7
7Luminescent metal nanoclusters for biomedical applications显示文摘Luminescent metal nanoclusters (NCs) have recently emerged as a novel class of luminescent nanomaterials and hold significant potential in biomedicine owing to their ultrasmall (<2nm) size,excellent photostability,and good biocompatibility.The recent rapid advances in the synthesis and functionalization of luminescent metal NCs have enabled scientists to develop colorful nanomaterials and nanodevices for a wide range of biomedical applications.In this review,we summarize the characteristics and advantages of luminescence from metal NCs,and highlight their applications in biomedicine.We focus on the research in biomedical detection,bio-imaging,drug delivery,and therapy,especially for the advances in the last five years.Luminescent metal NCs display a series of unique superiorities in biomedical applications,and the recent achievements have brought a lot of benefits to the diagnosis and treatment of clinical diseases,especially for tumors and cancers.Finally,we put forward the main challenges that currently still hinder the basic science studies and the practical development of luminescent metal NCs in biomedical applications.Overall,we expect that luminescent metal NCs will play a much more important role in future biomedicine and clinical applications.Yu Su Tiantian Xue Yuxin Liu Jinxia Qi Rongchao Jin Zhenkun Lin 2019Nano Research2019,12,6:6
8Study of Laser Ocular Effect and Damage显示文摘LIU Haifeng LUO Zhenkun ZHANG Jian 2005美国中华健康卫生杂志2005,8,3:5
9Hilger-type impulsive differential inequality and its application to impulsive synchronization of delayed complex networks on time scales显示文摘The synchronization and synchronous control of complex networks[1]have rich dynamics and are lately receiving much needed attention[2–6].Owing to the major role that impulsive control plays[6]in investigating synchronization problems and impulsive synchronization in dynamical networks,researchers have devoted more time researching them[2–6].However,most of the existing literature concerning impulsive effects are confined to continuous or discrete time domains[2,6].Zhenkun HUANG Jinde CAO Youssef N.RAFFOUL 2018Science China(Information Sciences)2018,61,7:4
10Self-excitation of neurons leads to multiperiodicity of discrete-time neural networks with distributed delays显示文摘In this paper, we investigate the interesting multiperiodicity of discrete-time neural networks with excitatory self-connections and distributed delays. Due to self-excitation of neurons, we construct 2N close regions in state space for N-dimensional networks and attain the coexistence of 2N periodic sequence solutions in these close regions. Meanwhile we estimate exponential attracting domain for each periodic sequence solution and apply our results to discrete-time analogues of periodic or autonomous neural networks. Under self-excitation of neurons, numerical simulations are performed to illustrate the effectiveness of our results.HUANG ZhenKun WANG XingHua SANNAY Mohamad 2011Science China(Information Sciences)2011,54,2:4
11Machine Learning-Based Multi-Modal Information Perception for Soft Robotic Hands显示文摘This paper focuses on multi-modal Information Perception(IP)for Soft Robotic Hands(SRHs)using Machine Learning(ML)algorithms.A flexible Optical Fiber-based Curvature Sensor(OFCS)is fabricated,consisting of a Light-Emitting Diode(LED),photosensitive detector,and optical fiber.Bending the roughened optical fiber generates lower light intensity,which reflecting the curvature of the soft finger.Together with the curvature and pressure information,multi-modal IP is performed to improve the recognition accuracy.Recognitions of gesture,object shape,size,and weight are implemented with multiple ML approaches,including the Supervised Learning Algorithms(SLAs)of K-Nearest Neighbor(KNN),Support Vector Machine(SVM),Logistic Regression(LR),and the unSupervised Learning Algorithm(un-SLA)of K-Means Clustering(KMC).Moreover,Optical Sensor Information(OSI),Pressure Sensor Information(PSI),and Double-Sensor Information(DSI)are adopted to compare the recognition accuracies.The experiment results demonstrate that the proposed sensors and recognition approaches are feasible and effective.The recognition accuracies obtained using the above ML algorithms and three modes of sensor information are higer than 85 percent for almost all combinations.Moreover,DSI is more accurate when compared to single modal sensor information and the KNN algorithm with a DSI outperforms the other combinations in recognition accuracy.Haiming Huang Junhao Lin Linyuan Wu Bin Fang Zhenkun Wen Fuchun Sun 2020Tsinghua Science and Technology2020,25,2:4
12GPS dynamic cycle slip detection and correction with baseline constraint显示文摘When the cycle slips take place in the attitude determination of a moving platform, the precision of the attitude will be impaired badly. A method of cycle slip detection and correction is proposed, which is suitable to the dynamic measurement using GPS carrier phase: the cycle slips detection is first achieved by triple difference observables, then the cycle slips correction is performed with baseline length constraint. The simulation results show that the proposed method is effective to the dynamic cycle slips problem.Liu Zhenkun Huang Shunji 2009Journal of Systems Engineering and Electronics2009,20,1:3
13Optical Image Encryption Based on Mixed Chaotic Maps and Single-Shot Digital Holography显示文摘Random phase masks play a key role in optical image encryption schemes based on double random phase technique. In this paper, a mixed chaotic method is proposed, which can efficiently solve some weaknesses that one-dimensional(1-D) single chaotic maps encounter to generate random phase masks. Based on the chaotic random phase masks, optical image encryption and decryption are realized with a single-shot digital holographic technique. In the proposed encryption scheme, the initial value and parameters of mixed chaotic maps serve as secret keys,which is convenient for the key management and transmission. Moreover, it also possesses high resistance against statistical attack, brute-force attack, noise attack and shear attack. Simulation results and security analysis verify the validity and security of the proposed encryption scheme.Yonggang Su Chen Tang Xia Chen Biyuan Li Wenjun Xu Zhenkun Lei 2017Transactions of Tianjin University2017,23,2:3
14Lens distortion correction based on one chessboard pattern image显示文摘这份报纸建议西洋象棋盘角落的一个察觉方法改正照相机 distortionsincluding 光线的失真, decentering 失真和棱柱失真。这个建议方法能完成高角落察觉率。然后,我们使用了反复的过程优化失真参数最小化失真剩余。首先,在这个方法,非失真点被四个点在图象中心附近评估;第二, Levenberg-Marquardt 非线性的优化算法被采用计算失真参数,然后由这些参数改正图象;第三,我们在改正的图象上计算了角落点,并且重复了以前的二步直到失真参数收敛。结果证明由反复的过程的建议方法能在可以忽略的图象中心和一根线的失真剩余的一般水准附近做细微失真的影响是几乎 0.3 个象素。Yubin WU Shixiong JIANG Zhenkun XU Song ZHU Danhua CAO 2015Frontiers of Optoelectronics2015,8,3:3
15Regulation of sister chromatid cohesion by nuclear PD-L1显示文摘Programmed death ligand-1(PD-L1 or B7-H1)is well known for its role in immune checkpoint regulation,but its function inside the tumor cells has rarely been explored.Here we report that nuclear PD-L1 is important for cancer cell sister chromatid cohesion.We found that depletion of PD-L1 suppresses cancer cell proliferation,colony formation in vitro,and tumor growth in vivo in immune-deficient NSG mice independent of its role in immune checkpoint.Specifically,PD-L1 functions as a subunit of the cohesin complex,and its deficiency leads to formation of multinucleated cells and causes a defect in sister chromatid cohesion.Mechanistically,PD-L1 compensates for the loss of Sororin,whose expression is suppressed in cancer cells overexpressing PD-L1.PD-L1 competes with Wing Apart-Like(WAPL)for binding to PDS5B,and secures proper sister chromatid cohesion and segregation.Our findings suggest an important role for nuclear PD-L1 in cancer cells independent of its function in immune checkpoint.Jia Yu Bo Qin Ann MMoyer Somaira Nowsheen Xinyi Tu Haidong Dong Judy CBoughey Matthew PGoetz Richard Weinshilboum Zhenkun Lou Liewei Wang 2020Cell Research2020,30,7:3
16SARS-CoV-2 non-structural protein 13 (nspl3) hijacks host deubiquitinase USP13 and counteracts host antiviral immune response显示文摘Dear Editor,COVID-19(Coronavirus Disease-2019),a respiratory disease caused by the novel virus strain,SARS-CoV-2(severe acute respiratory syndrome coronavirus 2),an enveloped,positive-sense,single-stranded RNA betacoronavirus of the family Corona-viridae,has spread worldwide.1 Notably,SARS-CoV-2 infection led to poor induction of typeⅠ interferon response,and the impaired type Ⅰ IFN responses have been shown to be associated with severe COVID-19 disease.2 However,molecular mechanisms by which SARS-CoV-2 suppresses type Ⅰ IFN production,and how host cells respond to the inhibition of type Ⅰ IFN response during SARS-CoV-2 infection,remain largely unknown.Guijie Guo Ming Gao Xiaochen Gao Bibo Zhu Jinzhou Huang Kuntian Luo Yong Zhang Jie Sun Min Deng Zhenkun Lou 2021Signal Transduction and Targeted Therapy2021,6,4:2
17Generation of Tripotent Neural Progenitor Cells from Rat Embryonic Stem Cells显示文摘老鼠是为药理学和生理的研究的一个珍贵模型。胚胎的茎(物件) 房间衬里的 Germline 能干的老鼠成功地被建立了,维持物件细胞的自我更新的、无差别的状态的分子的网络也好揭开。然而,很少对区别策略和这些真老鼠 pluripotent 干细胞怎么产生特定的房间类型的内在的机制被知道。这研究的目的是调查物件房间的神经区别能力。借助于一个修改过程基于 激活mitogen 的蛋白质 kinase ( MAPK )和肝糖 synthase kinase 的以前的出版物联合 3 ( GSK3 )禁止者(二个禁止者, 2i )与喂调节中等,我们成功地从物件房间获得了高质量的老鼠胚胎植物或动物身体(美国南北战争时南军士兵)然后区分了他们到 tripotent 神经祖先。这些物件导出房间的神经祖先房间(rNPCs ) 能够自我更新并且产生所有三个神经的系,包括的星形细胞, oligodendrocytes,和神经原。而且,这些导出房间的神经原染色了的物件为 -aminobutyric 酸(伽马氨基丁酸) 和酷氨酸 hydroxylase (TH ) 积极。在摘要,我们为区分物件房间到 tripotent 开发一个试验性的系统神经祖先,它可以为学习象 Parkinson 的疾病和老鼠神经系统的开发那样的许多 neurodegenerative 混乱的致病为药理学测试和一个珍贵平台提供一个强大的工具。Zhenkun Wang Chao Sheng Tianda Li Fei Teng Lisi Sang Fenglin Cao Ziwei Wang Wanwan Zhu Wei Li Xiaoyang Zhao Zhonghua Liu Liu Wang Qi Zhou 2012Journal of Genetics and Genomics2012,39,12:2
18To move or stay?A cellular automata model to predict urban growth in coastal regions amidst rising sea levels显示文摘Low-lying coastal cities are widely acknowledged as the most densely populated places of urban settlement;they are also more vulnerable to risks resulting from intensive land use and land cover change,human activities,global climate change,and the rising sea levels.This study aims to predict how urban growth is affected by sea level rise(SLR)in the Australian context.We develop an urban cellular automata model incorporating urban planning policies as potential drivers or constraints of urban growth under different SLR scenarios and adaption strategies.Drawing on data capturing the socioeconomic and environmental factors in South East Queensland,Australia,our model is positioned to address one core research question:how does SLR affect future urban growth and human resettlement?Results show that urban growth in coastal regions varies depending on the extent to which the sea level rises and is affected by a combination of factors relating to urban planning and human adaptation strategies.Our study demonstrates the complexity of urban growth in coastal regions and the nuanced outcomes under different adaptation strategies in the context of rising sea levels.Siqin Wang Yan Liu Yongjiu Feng Zhenkun Lei 2021International Journal of Digital Earth2021,14,9:2
19Clinical relevance of angiographic coronary collaterals during primary coronary intervention for acute ST-elevation myocardial infarction显示文摘Shen Ying Wu Feng Pan Chunzang Zhu Tianqi Zhang Qi Zhang Ruiyan Ding Fenghua Lu Lin Hu Jian Yang Zhenkun Shen Weifeng Wu Zonggui 2014Chinese Medical Journal2014,,1:2
20Research on ambiguity resolution aided with triple difference显示文摘The ambiguity resolution in the field of GPS is investigated in detail.A new algorithm to resolve the ambiguity is proposed.The algorithm first obtains the floating resolution of the ambiguity aided with triple difference measurement.Decorrelation of searching space is done by reducing the ambiguity covariance matrix's dimension to overcome the possible sick factorization of the matrix brought by Z-transformation.In simulation, the proposed algorithm is compared with least-squares ambiguity decorrelation adjustment (LAMBDA).The result shows that the proposed algorithm is better than LAMBDA because of lesser resolving time,which approximately reduces 20% resolving time.Thus,the proposed algorithm adapts to the high dynamic real-time applications.Liu Zhenkun Huang Shunji 2008Journal of Systems Engineering and Electronics2008,19,6:2
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