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42篇 您的检索式:作者名="Zhang Xiangyan"
    题名 作者 年代 出处 被引量
1Comparison of microwave-assisted extraction of aloe-emodin in aloe with Soxhlet extraction and ultrasound-assisted extraction显示文摘This paper reports the extraction of aloe-emodin from aloe by microwave-assisted extraction.The effects of various factors,including the solvent,the ratio (mL/g) of the solvent to the sample,microwave irradiation time and microwave power,were discussed in the experiments.The yield of aloe-emodin was determined by HPLC.The optimized conditions for microwave-assisted extraction of aloe-emodin were concluded as follows: the solvent is 80% ethanol (V/V) solution,microwave irradiation time is 3 min and microwave power is 340 W.Additionally,HPLC fingerprint was developed for consistency evaluation of aloe.The similarities of 3 aloe samples obtained by microwave-assisted extraction,ultrasound-assisted extraction and Soxhlet extraction were more than 0.9,indicating that 3 aloe samples were consistent.Compared with Soxhlet extraction and ultrasound-assisted extraction,microwave extraction is a rapid method with higher yield and less solvent consumption.Aloe samples treated by microwave-assisted extraction,ultrasound-assisted extraction and Soxhlet extraction were observed using transmission electronic microscopy.The micrographs provide evidence of more breakage of chloroplasts treated by microwave-assisted extraction as compared to Soxhlet extraction and ultrasound-assisted extraction.WANG GuiHua SU Ping ZHANG Fan HOU XiangYan YANG Yi GUO ZhenKu 2011Science China Chemistry2011,54,1:8
2Targeted Mutagenesis of NAC Transcription Factor Gene,OsN AC041,Leading to Salt Sensitivity in Rice显示文摘Salinity is a major abiotic stress factor that seriously affects plant growth. Many genes are involved in the response to salt stress with various metabolism pathways. A number of plant transcription factor family genes have been found to be involved in the salt stress response, and NAM, ATAF and CUC(NAC) transcription factors are thought to act as active regulators during abiotic stress, especially salt stress. In this study, we detected a rice NAC transcription factor coding gene, OsNAC041, and confirmed that it influenced the germination of seeds under salt stress and salt tolerance of plants. OsNAC041 was primarily expressed in the leaves and located in the nucleus. Furthermore, the CRISPR/Cas9 method was used to obtain a targeted osnac041 mutant, of which the plant height was higher than that of the wild-type, showing increased salt sensitivity. Moreover, RNA-seq analysis revealed a number of differentially expressed genes(DEGs) involved in several important signaling pathways in the osnac041 mutant. Subsequently, Kyoto Encyclopedia of Genes and Genomes annotation also revealed differential expression of DEGs associated with mitogen-activated protein kinase signaling, peroxisome, eukaryotictype ABC transporters, photosynthesis and plant hormones, which are involved in stress-related signaling pathways. Overall, our study suggested that OsNAC041 was involved in the salt stress response in rice. These findings not only provide empirical evidence of OsNAC041 function, but also provide new insight into its potential application in rice resistance breeding.WANG Bo ZHONG Zhaohui ZHANG Huanhuan WANG Xia LIU Binglin YANG Lijia HAN Xiangyan YU Deshui ZHENG Xuelian WANG Chunguo SONG Wenqin CHEN Chengbin ZHANG Yong 2019Rice science2019,26,2:8
3The Suitability of Using Leaf Area Index to Quantify Soil Loss under Vegetation Cover显示文摘Soil erosion by water under forest cover is a serious problem in southern China.A comparative study was carried out on the use of leaf area index(LAI) and vegetation fractional coverage(VFC) in quantifying soil loss under vegetation cover.Five types of vegetation with varied LAI and VFC under field conditions were exposed to two rainfall rates(40 mm h-1 and 54 mm h-1) using a portable rainfall simulator.Runoff rate,sediment concentration and soil loss rate were measured at relatively runoff stable state.Significant negative exponential relationship(p < 0.05,R2 = 0.83) and linear relationship(p < 0.05,R2 = 0.84) were obtained between LAI and sediment concentration,while no significant relationship existed between VFC and sediment concentration.The mechanism by which vegetation canopy prevents soil loss was by reducing rainfall kinetic energy and sediment concentration.LAI could better quantify such a role than VFC.However,neither LAI nor VFC could explain runoff rate or soil loss rate.Caution must be taken when using LAI to quantify the role of certain vegetation in soil and water conservation.ZHANG Wentai YU Dongsheng SHI Xuezheng WANG Hongjie GU Zhujun ZHANG Xiangyan TAN Manzhi 2011Journal of Mountain Science2011,8,4:7
4Optical observations of LIGO source GW 170817 by the Antarctic Survey Telescopes at Dome A,Antarctica显示文摘The LIGO detection of gravitational waves(GW) from merging black holes in 2015 marked the beginning of a new era in observational astronomy. The detection of an electromagnetic signal from a GW source is the critical next step to explore in detail the physics involved. The Antarctic Survey Telescopes(AST3),located at Dome A, Antarctica, is uniquely situated for rapid response time-domain astronomy with its continuous night-time coverage during the austral winter. We report optical observations of the GW source(GW 170817) in the nearby galaxy NGC 4993 using AST3. The data show a rapidly fading transient at around 1 day after the GW trigger, with the i-band magnitude declining from 17:23 ± 0:13 magnitude to 17:72 ± 0:09 magnitude in ~1:8 h. The brightness and time evolution of the optical transient associated with GW 170817 are broadly consistent with the predictions of models involving merging binary neutron stars. We infer from our data that the merging process ejected about ~10^(-2) solar mass of radioactive material at a speed of up to 30% the speed of light.lei hu xuefeng wu igor andreoni michael c.b.ashley jeff cooke xiangqun cui fujia du zigao dai bozhong gu yi hu haiping lu xiaoyan li zhengyang li ensi liang liangduan liu bin ma zhaohui shang tianrui sun n.b.suntzeff charling tao syed a.uddin lifan wang xiaofeng wang haikun wen di xiao jin xu ji yang shihai yang xiangyan yuan hongyan zhou hui zhang jilin zhou zonghong zhu 2017Science Bulletin2017,62,21:6
5Genetic environment of β-lactamase genes of extended-spectrum β-lactamase-producing Klebsiella pneumoniae isolates from patients with lower respiratory tract infection in China显示文摘Liu Lin Wang Xiaorong An Shuchang Zhang Xiangyan Chen Lin Li Yuqian Xu Li Zhang Yijie Gao Zhancheng 2014Chinese Medical Journal2014,,13:5
6Neuroendocrine regulation of somatic growth in fishes显示文摘Growth is a polygenic trait that is under the influence of multiple physiological pathways regulating energy metabolism and muscle growth.Among the possible growth-regulating pathways in vertebrates,components of the somatotropic axis are thought to have the greatest influence.There is growing body of literature focusing on the somatotropic axis and its role regulating growth in fish.This includes research into growth hormone,upstream hypothalamic hormones,insulin-like growth factors,and downstream signaling molecules.Many of these signals have both somatic effects stimulating the growth of tissues and metabolic effects that play a role in nutrient metabolism.Signals of other endocrine axes exhibit profound effects on the function of the somatotropic axis in vivo.In this review we highlight recent advances in our understanding of the teleost fish endocrine somatotropic axis,including emerging research using genetic modified models.These studies have revealed new aspects and challenges associated with regulation of the important steps of somatic growth.DAI XiangYan ZHANG Wei ZHUO ZiJian HE JiangYan YIN Zhan 2015Science China(Life Sciences)2015,58,2:5
7Tribological Behavior of In Situ TiC/Graphene/Graphite/Ti6Al4V Matrix Composite Through Laser Cladding显示文摘The TiC/graphene/graphite/Ti6 Al4 V composite coating was prepared by laser cladding.The microstructure and tribological behavior of the coating were studied.The in situ reaction between graphene and Ti occurred,and feathery TiC was formed.The feathery TiC was homogeneously distributed betweenα’acicular martensites which was refined with the addition of graphene.Some graphene was transformed into allotrope graphite under the laser irradiation.The TiC hard particles and the self-lubrication of graphene/graphite improved the wear resistance of composite coating.The wear rate and friction coefficient of TiC/graphene/graphite/Ti6 Al4 V composite coating decreased with the increase in sliding speed,a mechanical mixing layer(MML)was formed on the wear surface of the composite coating under the frictional heat,which protected the substrate and reduced the contact.Because of the self-lubricating properties of graphene/graphite,interlayer sliding occurred easily,which also effectively reduced friction.The wear rate of TiC/graphene/graphite/Ti6 Al4 V composite coating increased with the increase in load,but the friction coefficient decreased.The plastic deformation of subsurface layer was more serious under high load,and a stable self-lubricating MML with a protective effect was formed between the wear interfaces,which reduced the friction coefficient.With the increase in load,the wear mechanism changed from abrasive and oxidation wear to delamination,fatigue and oxidation wear.Zhanyong Zhao Lizheng Zhang Peikang Bai Wenbo Du Shaowei Wang Xiangyan Xu Qingnan Dong Yuxin Li Bing Han 2021Acta Metallurgica Sinica(English Letters)2021,34,10:5
8Functions and clinical significance of mechanical tumor microenvironment:cancer cell sensing,mechanobiology and metastasis显示文摘Dynamic and heterogeneous interaction between tumor cells and the surrounding microenvironment fuels the occurrence,progression,invasion,and metastasis of solid tumors.In this process,the tumormicroenvironment(TME)fractures cellular and matrix architecture normality through biochemical and mechanical means,abetting tumorigenesis and treatment resistance.Tumor cells sense and respond to the strength,direction,and duration of mechanical cues in the TME by various mechanotransduction pathways.However,far less understood is the comprehensive perspective of the functions and mechanisms of mechanotransduction.Due to the great therapeutic difficulties brought by the mechanical changes in the TME,emerging studies have focused on targeting the adverse mechanical factors in the TME to attenuate disease rather than conventionally targeting tumor cells themselves,which has been proven to be a potential therapeutic approach.In this review,we discussed the origins and roles ofmechanical factors in the TME,cell sensing,mechano-biological coupling and signal transduction,in vitro construction of the tumormechanicalmicroenvironment,applications and clinical significance in the TME.Hanying Zhou Meng Wang Yixi Zhang Qingqing Su Zhengxin Xie Xiangyan Chen Ran Yan Ping Li Tingting Li Xiang Qin Hong Yang ChunhuiWu Fengming You Shun Li Yiyao Liu 2022Cancer Communications2022,42,5:3
9The progress and prospect of assessment measures of uterine cavity function for infertility patients显示文摘Objective:To explore the progress and prospect of evaluation methods for infertility patients.Methods:From September 2017 to December 2020,199 cases of infertility patients who have accepted mini-hysteroscopy examination in the Department of Gynecological Endocrinology,Beijing Obstetrics and Gynecology Hospital,Capital Medical University.The patients who had primary ovary insufficiency,tubal infertility were excluded;patients with hysteroscopy contradiction,such as acute or sub-acute vaginal tract inflammation,endometrium lesion or endometrium carcinoma,severe cardiovascular,liver or kidney insufficiency were excluded.40 patients were excluded and 15 patients lost follow up,144 patients were eventually included in the analysis.The patient’s age,body mass index,infertility etiology,preoperative and postoperative stimulate ovulation cycle,pregnancy state and pregnancy time were recorded.The effect of mini-hysteroscopy on ovulation induction cycle was analyzed in pregnant patients.Results:The average age of 144 patients was 32.10±4.67 years old.96(66.67%)patients were found to have intrauterine abnormalities,while 48(33.33%)patients were found to have normal intrauterine cavity.48 cases of pregnancy,accounting for 33.33%;the median and interquartile ranges[M(Q1,Q3)]of ovulation induction cycles before and after surgery were respectively[3(0,5)],[2(1,3)],the difference was statistically significant(P<0.05).Among the 48 pregnant patients,32 of them had no structural lesions in hysteroscopy,the ovulation induction cycle of these patients before and after hysteroscopy were respectively[5(0,9)],[1(0,3)],the difference was statistically significant(P<0.05).Conclusion:Uterine cavity evaluation is important for the assessments of fertility.As an advanced diagnosis instrument,mini-hysteroscopy can not only timely detect the intrauterine abnormalities of patients,hut also with great application value in shorten the ovulation cycle in infertility patients and increase the pregnancy rate.Luping Zhang Rui Ju Xiangyan Ruan Yinmei Dai Husheng Wang Fengyu Jin Jing Jin Muqing Gu Jiaojiao Cheng Yu Yang Xin Xu Thomas Roemer 2021Global Health Journal2021,5,2:3
10New insights into follicular helper T cell response and regulation in autoimmune pathogenesis显示文摘Follicular helper T (Tfh) cells play a key role in driving B cell activation and differentiation during germinal center reactions in immune responses and autoimmune development, and these cells are characterized by high expression of CXCR5, PD1, ICOS, IL-21 and BCL6. Increasing evidence indicates that the functional dysregulation of Tfh cells contributes to the pathogenesis of autoimmune diseases, including primary Sjögren’s syndrome (pSS), which is a common autoimmune disease characterized by lymphocytic infiltration and tissue inflammation in salivary glands (SGs) and lacrimal glands that leads to dry mouth and dry eyes.1 Here, we provide a brief commentary on recent advances in understanding the Tfh cell response with a focus on new insights into Tfh cell regulation and therapeutic implications in autoimmune diseases.Fan Xiao Man Han Ke Rui Xiangyan Ai Jie Tian Wen Zhang Futao Zhao Yan Zhao Quan Jiang Liwei Lu 2021Cellular & Molecular Immunology2021,18,6:3
11An Improved Method for the Fitting and Prediction of the Number of COVID-19 Confirmed Cases Based on LSTM显示文摘New coronavirus disease(COVID-19)has constituted a global pandemic and has spread to most countries and regions in the world.Through understanding the development trend of confirmed cases in a region,the government can control the pandemic by using the corresponding policies.However,the common traditional mathematical differential equations and population prediction models have limitations for time series population prediction,and even have large estimation errors.To address this issue,we propose an improved method for predicting confirmed cases based on LSTM(Long-Short Term Memory)neural network.This work compares the deviation between the experimental results of the improved LSTM prediction model and the digital prediction models(such as Logistic and Hill equations)with the real data as reference.Furthermore,this work uses the goodness of fitting to evaluate the fitting effect of the improvement.Experiments show that the proposed approach has a smaller prediction deviation and a better fitting effect.Compared with the previous forecasting methods,the contributions of our proposed improvement methods are mainly in the following aspects:1)we have fully considered the spatiotemporal characteristics of the data,rather than single standardized data.2)the improved parameter settings and evaluation indicators are more accurate for fitting and forecasting.3)we consider the impact of the epidemic stage and conduct reasonable data processing for different stage.Bingjie Yan Jun Wang Zhen Zhang Xiangyan Tang Yize Zhou Guopeng Zheng Qi Zou Yao Lu Boyi Liu Wenxuan Tu Neal Xiong 2020Computers, Materials & Continua2020,,9:2
12High prevalence of pathogenic Leptospira in wild and domesticated animals in an endemic area of China显示文摘Objective:To assess the prevalence of Leptospira detected in wildlife and domesticated animals in Jiangxi Province,China,in 2009.Methods:Urine samples from 28 buffaloes and kidney samples from 50 pigs,50 dogs and 38 rats were collected from Fuliang and Shangrao County,Jiangxi Province,China,in October 2009.Polymerase chain reaction(PCR) and culture analyses were used to detect Leptospira.The cultured isolates were typed using the microscopic agglutination lest(MAT).Results:The results showed that rats potentially serve as the main reservoir of leptospiral infection,followed by dogs.Although 16%of rats(6/38) were positive using culture analysis,PCR analysis using the diagnostic primers G1/G2 and B64Ⅰ/B64Ⅱor lipLS2 showed identification as 50%and 24%,respectively,of the rat samples as positive for the presence of leptospiral DNA.Conclusions:PCR-based detection of leptospiral DNA in infected kidney tissues of reservoirs is more efficient when using G1/G2 primers than lipL32 primers. However,the latter primers have a potential application for detection in urine samples.The alarmingly high prevalence of leptospiral DMA in the wild rat population near human habitation underscores the utility of routine Leptospira surveillance,preferably using PCR methods,which are more sensitive than traditional culture-based methods.Wang Yalin Zeng Lingbing Yang Hongliang Xu Jianmin Zhang Xiangyan Guo Xiaokui Pal Utpal Qin Jinhong 2011Asian Pacific Journal of Tropical Medicine2011,4,11:2
13A novel superconducting quantum interference device for biomagnetic measurements显示文摘Superconducting Quantum Interference Device (SQUID) can provide an ultrahigh magnetic sensitivity for the biomagnetic measurements. In this paper, a SQUID bootstrap circuit (SBC) gradiometer was designed and fabricated. Using the SBC gradiometer, magnetocardiography (MCG), fetal MCG and magnetoencephalography (MEG) signals were detected in a magnetically shielded room.ZHANG ShuLin ZHANG GuoFeng WANG YongLiang ZENG Jia QIU Yang LIU Ming KONG XiangYan XIE XiaoMing 2013Chinese Science Bulletin2013,58,24:2
14Mirror seeing of the Antarctic survey telescope显示文摘Site testing results indicate that Antarctic Dome A is an excellent ground-based astronomical site suitable for observations ranging from visible to infrared wavelengths. However, the harsh environment in Antarctica, especially the very low temperature and atmospheric pressure, always produces frost on the telescopes' mirrors, which are exposed to the air. Since the Dome A site is still unattended, the Antarctic telescope tubes are always designed to be fi lled with dry nitrogen, and the outer surfaces of the optical system are heated by an indium-tin oxide thin fi lm. These precautions can prevent the optical surfaces from frosting over, but they degrade the image quality by introducing additional mirror seeing. Based on testing observations of the second Antarctic Survey Telescope(AST3-2) in the Mohe site in China, mirror seeing resulting from the heated aspheric plate has been measured using micro-thermal sensors. Results comparing the real-time atmospheric seeing monitored by the Differential Image Motion Monitor and real-time examinations of image quality agree well.ZHANG Kaiyuan LI Zhengyang YUAN Xiangyan PEI Chong 2014Advances in Polar Science2014,25,3:2
15Defect-engineered Mn_(3)O_(4)/CNTs composites enhancing reaction kinetics for zinc-ions storage performance显示文摘The designing of reasonable nanocomposite materials and proper introduction of defect engineering are of great significance for the improvement of the poor electronic conductivity and slow reaction kinetics of manganese-based compounds. Herein, we report manganese-deficient Mn_(3)O_(4) nanoparticles which grow in-situ on highly conductive carbon nanotubes(CNTs)(denoted as DMOC) as an advanced cathode material for aqueous rechargeable zinc-ion batteries(RAZIBs). According to experimental and calculation results, the DMOC cathode integrates the advantages of enriched Mn defects and small particle size. These features not only enhance electronic conductivity but also create more active site and contribute to fast reaction kinetics. Moreover, the structure of DMOC is maintained during the charging and discharging process, thus benefiting for excellent cycle stability. As a result, the DMOC electrode delivers a high specific capacity of 420.6 m A h g^(-1) at 0.1 A g^(-1) and an excellent cycle life of 2800 cycles at 2.0 A g^(-1) with a high-capacity retention of 84.1%. In addition, the soft-packaged battery assembled with DMOC cathode exhibits long cycle life and high energy density of 146.3 Wh kg^(-1) at 1.0 A g^(-1) . The results are beneficial for the development of Zn/Mn_(3)O_(4) battery for practical energy storage.Xiuli Guo Hao Sun Chunguang Li Siqi Zhang Zhenhua Li Xiangyan Hou Xiaobo Chen Jingyao Liu Zhan Shi Shouhua Feng 2022Journal of Energy Chemistry2022,31,5:1
16Surface coal mining impacts on land use change and ecological service value:a case study in Shengli coalfield,Inner Mongolia显示文摘Coal plays a crucial role in global economic development and remains the most common and widely distributed fossil fuel worldwide.As the world's largest developing country,China's mining and utilization of coal resources have contributed signifcantly to the country’s rapid economic growth.Inner Mongolia is an ecologically fragile arid and semi-arid area of China.The exploitation of opencast mining has seriously hindered the sustainable use of regional land and the residents'well-being.Using ENVI-based remote sensing images from 2000,2005,2010,2015,and 2020,this study employed a random forest algorithm to divide land utilization types into construction land,vegetation,cultivated land,bare land,and water areas and analyzed the characteristics of land use and ecosystem service value changes over the past 20 years.The results were as follows:(1)Construction land in the mining area changed minimally from 2000 to 2020;vegetation and water bodies showed a decreasing trend,whereas bare and cultivated lands showed an increasing trend.Bare land exhibited the largest change in area proportion and water bodies the smallest.(2)The total ecosystem service value of the mining area declined from 10.939 to 9.527 billion Yuan.Vegetation ecosystem service value was the highest,followed by cultivated land and water,with the bare land ecosystem service value the lowest.(3)On a spatial scale,the total ecosystem service value of the Shengli mining area decreased year by year,indicating that land use changes in the mining area do have an impact on ecosystem service value.Lijia Zhang Xu Zhou Yan Zhou Ji Zhou Jiwang Guo Zihan Zhai Yan Chen Xiangyan Su Lingxiao Ying Liwei Wang Ying Qiao 2022International Journal of Coal Science & Technology2022,9,5:1
17Design oftheJointBearingFlexibleLaminated MembraneCoupling显示文摘Shentu Liufang Zhang Xiangyan 2004Mechanical Science and Technology2004,23,1:1
18A StudyontheCompensatoryCapacityforthe Angle- misalignmentoftheJointBearingFlexibleLaminatedMembraneCoupling显示文摘ShentuLiufang Zhang Xiangyan 2004JournalofHuaihaiInstituteofTechnology (NaturalSciencesEdition)2004,13,1:1
19北半球高山和极地虎耳草属物种丰富度的地理格局:温度和生境异质性的作用显示文摘现代气候、生境异质性和长期气候变化对森林生态系统中分布的木本植物的物种丰富度格局的影响在以往研究中受到广泛关注,但对高寒-极地生态系统中的草本植物物种丰富度格局及其影响因素的研究仍较少。本研究旨在检验以往研究中基于物种丰富度和环境因子关系提出的假说是否能够解释高寒-极地地区典型草本植物-虎耳草属(Saxifraga)的物种丰富度格局。本研究利用全球437种虎耳草属物种分布数据,探讨了全部物种、广域和狭域物种丰富度格局的影响因素。采用广义线性模型和空间自回归模型,评估了现代气候、生境异质性和历史气候对虎耳草属物种丰富度格局的影响。采用偏回归分析了不同变量对物种丰富度的独立解释率和共同解释率,并检验了4种广泛使用的物种丰富度与环境关系模型对物种丰富度格局的解释能力。研究结果表明,温度与虎耳草属所有物种和广域物种的物种丰富度格局呈显著负相关关系,是影响物种丰富度格局最重要的环境因子,这可能反映了虎耳草属对其祖先温带生态位的保守性。生境异质性和末次冰期以来的气候变化是虎耳草属狭域物种丰富度空间变异的最佳预测因子。总体而言,包含5个预测变量的组合模型可以解释大约40%–50%的虎耳草属物种丰富度的空间变异。此外,进化和生物地理过程在虎耳草属物种丰富度格局形成方面可能发挥了重要作用,这有待进一步研究。Lian Liu Xiaoting Xu Lei Zhang Yaoqi Li Nawal Shrestha Danilo M.Neves Qinggang Wang Hong Chang Xiangyan Su Yunpeng Liu Jianyong Wu Dimitar Dimitrov Zhiheng Wang Jianquan Liu 2022Journal of Plant Ecology2022,15,2:1
20A novel ofMANET management domain partition 显示文摘Ning Xiangyan Zhang Shunyi Liang Wei 2010EducationTechnology and Computer Science2010,,3:1
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