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A Machine Learning Made Catalog of FR-Ⅱ Radio Galaxies from the FIRST Survey
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作者 Bao-Qiang Lao Xiao-Long Yang +4 位作者 Sumit Jaiswal Prashanth Mohan xiao-hui sun Sheng-Li Qin Ru-Shuang Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期266-282,共17页
We present an independent catalog(FRIIRGcat)of 45,241 Fanaroff–Riley TypeⅡ(FR-Ⅱ)radio galaxies compiled from the Very Large Array Faint Images of the Radio Sky at Twenty-centimeters(FIRST)survey and employed the de... We present an independent catalog(FRIIRGcat)of 45,241 Fanaroff–Riley TypeⅡ(FR-Ⅱ)radio galaxies compiled from the Very Large Array Faint Images of the Radio Sky at Twenty-centimeters(FIRST)survey and employed the deep learning method.Among them,optical and/or infrared counterparts are identified for 41,425 FR-Ⅱs.This catalog spans luminosities 2.63×10^(22)≤L_(rad)≤6.76×10^(29)W Hz^(-1)and redshifts up to z=5.01.The spectroscopic classification indicates that there are 1431 low-excitation radio galaxies and 260 high-excitation radio galaxies.Among the spectroscopically identified sources,black hole masses are estimated for 4837 FR-Is,which are in 10^(7.5)■M_(BH)■10^(9.5)M_(⊙).Interestingly,this catalog reveals a couple of giant radio galaxies(GRGs),which are already in the existing GRG catalog,confirming the efficiency of this FR-I catalog.Furthermore,284new GRGs are unveiled in this new FR-I sample;they have the largest projected sizes ranging from 701 to1209 kpc and are located at redshifts 0.31<z<2.42.Finally,we explore the distribution of the jet position angle and it shows that the faint Images of the FIRST images are significantly affected by the systematic effect(the observing beams).The method presented in this work is expected to be applicable to the radio sky surveys that are currently being conducted because they have finely refined telescope arrays.On the other hand,we are expecting that further new methods will be dedicated to solving this problem. 展开更多
关键词 radio continuum galaxies-galaxies active-galaxies jets-galaxies STATISTICS
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内镜下套扎硬化序贯治疗食管曲张静脉疗效及预后影响因素的探讨 被引量:11
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作者 桑建忠 张红 +6 位作者 周建波 宋奇峰 孙晓辉 黄戬 施煜燕 杨倩倩 蔡升 《中国内镜杂志》 北大核心 2017年第3期56-63,共8页
目的观察内镜下套扎(EVL)及硬化序贯治疗在肝硬化食管静脉曲张患者中应用的疗效,并研究预后的相关危险因素。方法收集未进行内镜下治疗的食管静脉曲张破裂出血患者设为对照组,仅进行药物治疗,共106例,研究组为内镜下治疗+药物治疗患者,... 目的观察内镜下套扎(EVL)及硬化序贯治疗在肝硬化食管静脉曲张患者中应用的疗效,并研究预后的相关危险因素。方法收集未进行内镜下治疗的食管静脉曲张破裂出血患者设为对照组,仅进行药物治疗,共106例,研究组为内镜下治疗+药物治疗患者,入组共113例,研究组中又随机分为单纯套扎组(EVL组)和套扎硬化序贯组,观察治疗后曲张静脉消除率、再出血率、总治疗次数、死亡率和术中及术后并发症,进行比较。并比较对照组和研究组肝功能Child-Turcotte-Pugh(CTP)分级和终末期肝病模型(MELD)不同评分的再出血率和死亡率,分析预后影响因素,评价其对预后的诊断价值。结果对照组、EVL组和套扎硬化序贯组再出血率分别为41.51%、10.53%和10.64%,对照组与套扎硬化序贯组比较,差异有统计学意义(P=0.000);3组的死亡率分别为15.09%、5.26%和2.13%,对照组与EVL组、对照组与序贯组、EVL与序贯组比较,分别为P>0.05、P=0.001和P>0.05;套扎硬化序贯治疗的半年内复发率44.68%,EVL组复发率73.68%,两者比较差异有统计学意义(P=0.021);无论是对照组还是EVL组和序贯治疗组,肝功能CTP C级的再出血、死亡率明显高于A级;MELD模型中,受试者工作特征曲线(ROC)的曲线下面积(AUC)再出血率对照组、序贯组分别为0.944和0.851,死亡率两组分别为0.881和0.984,而复发率EVL组、序贯组分别为0.914和0.765,MELD评分对再出血和死亡的预测具有重要价值。结论套扎硬化序贯治疗能明显降低肝硬化食管曲张静脉患者的再出血率和死亡率,且套扎硬化序贯治疗的复发率要低于单纯套扎。肝功能CTP评分评级和MELD评分对再出血和死亡的预测均具有重要价值,套扎硬化序贯治疗能明显降低CTP为B级和C级静脉曲张的再出血和死亡率,并提高再出血和死亡的MELD阈值。 展开更多
关键词 套扎硬化序贯治疗 CTP MELD
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Efficacy of intravenous zoledronic acid in the prevention and treatment of osteoporosis:A meta-analysis 被引量:15
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作者 Jun Zhang Ran Wang +5 位作者 Yi-Lei Zhao xiao-hui sun Hong-Xing Zhao Tan Lu De-Cai Chen Hai-Bin Xu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第9期743-748,共6页
Objective:To compare the eflect of zoledronic acid in treatment and prevention of osteoporosis with placebo.Methods:Random control trials regarding zoleilroiiic acid in treatment of osteoporosis were retrieved by sele... Objective:To compare the eflect of zoledronic acid in treatment and prevention of osteoporosis with placebo.Methods:Random control trials regarding zoleilroiiic acid in treatment of osteoporosis were retrieved by selecting Medline.EMbase and Pubmed databases till April 2012. The RevMan software was used for all of the statistical analysis.Results:A total of 9 trials were included in this meta-analysis.The pooled effect shewed that zoledronic acid could increase the bone mineral density by 2.98 times compared with placebo,and reduce the rate of fracture in patients by 32%.The results should the zoledronic acid intervention had significantly less serious adverse events than controls,and the odds ratio was 0.81(0.76-0.87).The longer term intervention, more than 12 months intervention,could gain a better prevention effect for osteoporosis(OR,95% CI for RMD was 3.35.2.77-3.92:for fracture was 0.67.0.54-0.82).Conclusions:This present study shows that zoledronic acid could be effective approach in the prevention of osteoporosis,and could increase the bone mineral density and reduce the risk ol facture. 展开更多
关键词 Systematic review INTRAVENOUS zoledronic acid OSTEOPOROSIS BONE MINERAL density Fracture
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Treatment of bilateral granulomatous lobular mastitis during lactation with traditional Chinese medicine: A case report 被引量:6
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作者 Zhi-Yuan Li Xiao-Mei sun +5 位作者 Jing-Wei Li Xiao-Fei Liu Zi-Yuan sun Han-Han Chen Yan-Ling Dong xiao-hui sun 《World Journal of Clinical Cases》 SCIE 2021年第27期8249-8259,共11页
BACKGROUND Granulomatous lobular mastitis(GLM)is a type of benign chronic inflammatory disease that poses therapeutic challenges to healthcare providers.The diagnosis of GLM relies on tissue biopsy,and incorrect treat... BACKGROUND Granulomatous lobular mastitis(GLM)is a type of benign chronic inflammatory disease that poses therapeutic challenges to healthcare providers.The diagnosis of GLM relies on tissue biopsy,and incorrect treatment may lead to delayed diagnosis,considerable aesthetic damage,and even mastectomy.CASE SUMMARY We report the case of a 37-year-old Chinese woman who was lactating and had GLM in both breasts.At the time of treatment,the right breast had a mass of approximately 15 cm×11 cm,which was hard and had poor mobility.Multiple skin ulcerations and pus spills were also observed on the surface of the breast.The left breast had a mass of about 13 cm×9 cm,which was hard and had poor mobility.CONCLUSION Herein,we report a case of bilateral GLM in a lactating woman that was successfully treated with traditional Chinese medicine(TCM),without the requirement for surgery or other treatments.Therefore,TCM may have advantages in the nonsurgical treatment of GLM. 展开更多
关键词 Bilateral mammary gland Granulomatous lobular mastitis Lactation Traditional Chinese medicine Non-surgical treatment Case report
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High-precision nonisothermal transient wellbore drift flow model suitable for the full flow pattern domain and full dip range 被引量:2
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作者 Wen-Qiang Lou Da-Lin sun +5 位作者 xiao-hui sun Peng-Fei Li Ya-Xin Liu Li-Chen Guan Bao-Jiang sun Zhi-Yuan Wang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期424-446,共23页
A reliable multiphase flow simulator is an important tool to improve wellbore integrity and production decision-making.To develop a multiphase flow model with high adaptability and high accuracy,we first build a multi... A reliable multiphase flow simulator is an important tool to improve wellbore integrity and production decision-making.To develop a multiphase flow model with high adaptability and high accuracy,we first build a multiphase flow database with 3561 groups of data and developed a drift closure relationship with stable continuity and high adaptability.Second,a high-order numerical scheme with strong fault capture ability is constructed by effectively combining MUSCL technology,van Albada slope limiter and AUSMV numerical scheme.Finally,the energy equation is coupled into the AUSMV numerical scheme of the drift flow model in the form of finite difference.A transient non-isothermal wellbore multiphase flow model with wide applicability is formed by integrating the three technologies,and the effects of various factors on the calculation accuracy are studied.The accuracy of the simulator is verified by comparing the measurement results with the blowout experiment of a full-scale experimental well. 展开更多
关键词 Drift closure relation Non-isothermal model HIGH-PRECISION Multiphase flow solver Wellbore pressure control
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The influence of marital status on the social dysfunction of schizophrenia patients in community 被引量:1
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作者 Xue-jie Li Jing-hua Wu +4 位作者 Jun-biao Liu Kai-ping Li Fang Wang xiao-hui sun Shi-hong Ma 《International Journal of Nursing Sciences》 2015年第2期149-152,共4页
Objective:Estimate predictive associations of marital status with social dysfunction in schizophrenia patients.Methods:817 schizophrenia patients lived in the community of Dongguan,Guangdong province,China,were invest... Objective:Estimate predictive associations of marital status with social dysfunction in schizophrenia patients.Methods:817 schizophrenia patients lived in the community of Dongguan,Guangdong province,China,were investigated with the Social Disability Screening Schedule(SDSS)during a three-month period(1.2010e3.2010).The demographic data were harvested.The c2 test,t test,and fisher's exact were used for comparisons between groups,as appropriate.Multinomial logistic regression(MLR)was used to analyze the predictive associations of demographic variables to the grading of social dysfunctions.Results:The study group consisted of male and female patients aged 16e59 years,407 females,and 410 males with the mean age(40.7±9.5)years.Analysis of the data revealed significant differences in course of disease and marital status among patients(with and without dysfunction).The married patient made a significant difference with divorced/widowed patient in mildlyemoderately social dysfunction.There was a significant difference in married and never-married patient with mildly and profoundly social dysfunction.Significant differences were noticed in the self care and occupational roles of the married patient with that of the never-married.Conclusion:This study confirmed that bad marital status is associated with higher odds of social dysfunction among patients with schizophrenia living in the community.These effects should be included in considerations of public health investments in preventing and treating mental disorders. 展开更多
关键词 China COMMUNITY Marital status SCHIZOPHRENIA Social dysfunction
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FAST Continuum Mapping of the SNR VRO 42.05.01 被引量:1
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作者 Li Xiao Ming Zhu +2 位作者 xiao-hui sun Peng Jiang Chun sun 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第3期33-38,共6页
The relativistic electrons rotate in the enhanced magnetic field of the supernova remnants and emit the synchrotron radio emission.We aim to use the Five-hundred-meter Aperture Spherical radio Telescope(FAST)to obtain... The relativistic electrons rotate in the enhanced magnetic field of the supernova remnants and emit the synchrotron radio emission.We aim to use the Five-hundred-meter Aperture Spherical radio Telescope(FAST)to obtain a sensitive continuum map of the supernova remnant VRO 42.05.01(G166.0+4.3)at 1240 MHz.The 500 MHz bandwidth is divided into low and high-frequency bands centered at 1085 and 1383 MHz to investigate the spectral index variations within the remnant,together with the Effelsberg 2695 MHz data.We obtained an integrated flux density of 6.2±0.4 Jy at 1240 MHz for VRO 42.05.01,consistent with previous results.The spectral index found from temperature-temperature plot(TT-plot)between 1240 and 2695 MHz agrees with previous values from408 MHz up to 5 GHz.The three-band spectral index distribution shows a clear flatter value ofα~-0.33 in the shell region and steeper index ofα=-0.36 to-0.54 in the wing region.The flatter spectral index in the shell region could be attributed to a second-order Fermi process in the turbulent medium in the vicinity of the shock and/or a higher compression ratio of shock and a high post-shock density than that in elsewhere. 展开更多
关键词 ISM:supernova remnants radio continuum:ISM methods:observational
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Discovery of Three Large HII Regions in the Galactic Plane 被引量:2
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作者 Wei-Bin Shi xiao-hui sun +2 位作者 Jin-Lin Han Xu-Yang Gao Li Xiao 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第5期575-579,共5页
We discovered three large HⅡ regions: G148.8+2.3, G149.5+0.0 and G169.9+2.0 in the Sino-German A6 cm polarization survey of the Galactic plane. They have been identified based on the flat spectral indexes and the... We discovered three large HⅡ regions: G148.8+2.3, G149.5+0.0 and G169.9+2.0 in the Sino-German A6 cm polarization survey of the Galactic plane. They have been identified based on the flat spectral indexes and the strong infrared emission properties. 展开更多
关键词 radio continuum general - methods observational - HⅡ regions
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Trajectory optimization of a deflectable nose missile
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作者 Zhi-yong Zhang Qi-zhong Tang +1 位作者 xiao-hui sun Zhi-hua Chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2017年第3期158-163,共6页
The deflectable nose missile has a longer range by deflecting its nose to improve its aerodynamic feature.Based on detached eddy simulation(DES), the supersonic flow fields of a missile with deflectable nose are simul... The deflectable nose missile has a longer range by deflecting its nose to improve its aerodynamic feature.Based on detached eddy simulation(DES), the supersonic flow fields of a missile with deflectable nose are simulated numerically and its aerodynamic force coefficients are calculated under the condition of the deflection angles vary from 0° to 8°, angles of attack, 0°-8°, and mach numbers, 2 to 5. Coupling these aerodynamic coefficients with the plumb plane ballistic equations, the extended flight range has been calculated. Furthermore, the genetic algorithm(GA) is employed for the solution of maximum range of the deflected missile. 展开更多
关键词 偏转角度 导弹 弹道优化 弹头 流场数值模拟 最大射程 动力学特征 气动力系数
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Polarised radio emission associated with HESS J1912+101
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作者 Wolfgang Reich xiao-hui sun 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第3期123-130,共8页
The shell-type TeV source HESS J1912+101 was tentatively identified as an old supernova remnant, but is missing counterparts at radio and other frequencies. We analysed the Sino-German Urumqiλ6 cm survey and the Effe... The shell-type TeV source HESS J1912+101 was tentatively identified as an old supernova remnant, but is missing counterparts at radio and other frequencies. We analysed the Sino-German Urumqiλ6 cm survey and the Effelsberg λ11 cm and λ21 cm surveys to identify radio emission from HESS J1912+101 to clarify the question of a supernova origin. We find a partial shell of excessive polarisation at λ6 cm at the periphery of HESS J1912+101. At λ11 cm, its polarised emission is faint and suffers from depolarisation, while at λ21 cm, no related polarisation is seen. We could not separate the shell's total intensity signal from the confusing intense diffuse emission from the inner Galactic plane. However, a high percentage of polarisation in the shell's synchrotron emission is indicated. Our results support earlier suggestions that HESS J1912+101 is an old supernova remnant. The synchrotron emission is highly polarised,which is typical for evolved supernova remnants with low surface brightness. 展开更多
关键词 RADIO CONTINUUM ISM-ISM INDIVIDUAL objects HESS J1912+101-ISM magnetic FIELDS
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A polarization study of the supernova remnant CTB 80
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作者 Xiang-Hua Li xiao-hui sun +1 位作者 Wolfgang Reich Xu-Yang Gao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第11期312-320,共9页
We present a radio polarization study of the supernova remnant CTB 80 based on images at1420 MHz from the Canadian Galactic Plane Survey,at 2695 MHz from the Effelsberg survey of the Galactic plane and at 4800 MHz fro... We present a radio polarization study of the supernova remnant CTB 80 based on images at1420 MHz from the Canadian Galactic Plane Survey,at 2695 MHz from the Effelsberg survey of the Galactic plane and at 4800 MHz from the Sino-Germanλ6 cm polarization survey of the Galactic plane.We obtained a rotation measure(RM)map using polarization angles at 2695 MHz and 4800 MHz as the polarization percentages are similar at these two frequencies.RM exhibits a transition from positive values to negative values along one of the shells hosting the pulsar PSR B1951+32 and its pulsar wind nebula.The reason for the change in sign remains unclear.We identified a partial shell structure,which is bright in polarized intensity but weak in total intensity.This structure could be part of CTB 80 or part of a new supernova remnant unrelated to CTB 80. 展开更多
关键词 ISM supernova remnants ISM magnetic fields POLARIZATION TECHNIQUES polarimetric
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New Continuum and Polarization Observations of the Cygnus Loop with FAST.II.Images and Analyses
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作者 xiao-hui sun Xu-Yang Gao +4 位作者 Wolfgang Reich Peng Jiang Di Li Huirong Yan Xiang-Hua Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第12期249-259,共11页
We present total-intensity and polarized-intensity images of the Cygnus Loop supernova remnant(SNR)observed by the Five-hundred-meter Aperture Spherical radio Telescope.The high angular-resolution and high-sensitivity... We present total-intensity and polarized-intensity images of the Cygnus Loop supernova remnant(SNR)observed by the Five-hundred-meter Aperture Spherical radio Telescope.The high angular-resolution and high-sensitivity images enable us to thoroughly compare the properties of the northern part with the southern part of the SNR.The central filament in the northern part and the southern part have a similar foreground rotation measure,meaning their distances are likely similar.The polarization analysis indicates that the random magnetic field is larger than the regular field in the northern part,but negligible in the southern part.The total-intensity image is decomposed into components of various angular scales,and the brightness-temperature spectral index of the shell structures in the northern part is similar to that in the southern part in the component images.All the evidence suggests that the northern and southern parts of the Cygnus Loop are situated and thus evolved in different environments of interstellar medium,while belonging to the same SNR. 展开更多
关键词 ISM:supernova remnants ISM:magnetic fields POLARIZATION techniques:polarimetric
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New continuum and polarization observations of the Cygnus Loop with FAST I.Data processing and verification
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作者 xiao-hui sun Mei-Niang Meng +5 位作者 Xu-Yang Gao Wolfgang Reich Peng Jiang Di Li Hui-Rong Yan Xiang-Hua Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第11期105-118,共14页
We report on the continuum and polarization observations of the Cygnus Loop supernova remnant(SNR)conducted by the Five-hundred-meter Aperture Spherical radio Telescope(FAST).FAST observations provide high angular res... We report on the continuum and polarization observations of the Cygnus Loop supernova remnant(SNR)conducted by the Five-hundred-meter Aperture Spherical radio Telescope(FAST).FAST observations provide high angular resolution and high sensitivity images of the SNR,which will help to disentangle its nature.We obtained Stokes I,Q and U maps over the frequency range of 1.03-1.46 GHz split into channels of 7.63 kHz.The original angular resolution is in the range of~3’-~3.’8,and we combined all the data at a common resolution of 4’.The temperature scale of the total intensity and the spectral index from the in-band temperature-temperature plot are consistent with previous observations,which validates the data calibration and map-making procedures.The rms sensitivity for the band-averaged total-intensity map is about 20 mK in brightness temperature,which is at the level of confusion limit.For the first time,we apply rotation measure(RM)synthesis to the Cygnus Loop to obtain the polarization intensity and RM maps.The rms sensitivity for polarization is about 5 mK,far below the total-intensity confusion limit.We also obtained RMs of eight extragalactic sources,and demonstrate that the wide-band frequency coverage helps to overcome the ambiguity of RM determinations. 展开更多
关键词 ISM:supernova remnants ISM:magnetic fields POLARIZATION techniques:polarimetric
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十年描银河:中德6 cm银道面偏振巡天的发现 被引量:1
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作者 高旭阳 孙晓辉 +4 位作者 韩金林 肖莉 石维彬 石惠 王陈 《科学通报》 EI CAS CSCD 北大核心 2021年第11期1315-1326,共12页
射电连续谱偏振观测是探测银河系星际介质性质的有力工具.中德6 cm银道面偏振巡天使用新疆天文台南山站25 m射电望远镜对银道面银经10°~230°、银纬±5°之间的区域进行了总强度和线偏振的巡测.历时10年,完成了世界上... 射电连续谱偏振观测是探测银河系星际介质性质的有力工具.中德6 cm银道面偏振巡天使用新疆天文台南山站25 m射电望远镜对银道面银经10°~230°、银纬±5°之间的区域进行了总强度和线偏振的巡测.历时10年,完成了世界上地基射电望远镜观测频率最高的银道面射电连续谱偏振巡天,揭示了银道面在6 cm波段的辐射分布和横向磁场取向.该巡天是国产数据描绘的银河系画卷,其较高的观测频率使得消偏振效应小,能够探测来自银河系更远处的偏振辐射.利用这些数据,巡天团队对银河系超新星遗迹、电离氢区、法拉第屏等多种射电目标的研究取得了系列性结果:先后发现了4颗新的银河系超新星遗迹,其中在2011年发布的两个新超新星遗迹G178.2-4.2和G25.1-2.3是国内学者首次使用国内射电望远镜完成的发现工作;对70多个已知超新星遗迹进行了流量密度、偏振和谱的测量,首次探测到超新星遗迹G16.2-2.7、G69.7+1.0、G84.2-0.8、G85.9-0.6、G205.5+0.5和G206.9+2.3的偏振辐射,新的6 cm波段总强度测量还为确定20个超新星遗迹的谱指数提供了关键数据;完成了对巡天范围内可以准确估计6 cm波段流量密度的401个HII区的统计和测量,补充了国际HII区列表中对于延展HII区的数据缺失.在弥漫辐射偏振探测方面,发现了若干在低频射电偏振观测数据中无法显现的、在总强度辐射上没有对应体的高法拉第旋率结构.巡天数据已经在国际学术界产生重要影响,并一直被用于科学研究. 展开更多
关键词 巡天 偏振 射电连续谱 超新星遗迹 HII区 磁场
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Multiple Functions of Ten-eleven Translocation 1 during Tumorigenesis 被引量:5
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作者 Yi-Ping Tian Yi-Min Zhu +1 位作者 xiao-hui sun Mao-De Lai 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第14期1744-1751,共8页
Objective: Aberrant expression of ten-eleven translocation 1 (TET1) plays a critical role in tumor development and progression. We systematically summarized the latest research progress on the role and mechanisms o... Objective: Aberrant expression of ten-eleven translocation 1 (TET1) plays a critical role in tumor development and progression. We systematically summarized the latest research progress on the role and mechanisms of TET1 in cancer biology. Data Sources: Relevant articles published in English from 1980 to April 2016 were selected from the PubMed database. Tile terms "'ten-eleven translocation 1," "'SmC," '5hmC," 'microRNA,'" "hypoxia," and "'embryonic stem cell'" were used tbr the search. Study Selection: Articles focusing on the role and mechanism ofTETI in tumor were reviewed, including clinical and basic research articles. Results: TET proteins, the key enzymes converting 5-methylcytosine to 5-hydroxymethylcytosine, play vital roles in DNA demethylation regulation. Recent studies have shown that loss of TETI is associated with tumorigenesis and can be used as a potential biomarker for cancer therapy, which indicates that TETI serves as tumor suppressor gene. Moreover, besides its dioxygenase activity, TET1 could induce epithelial-mesenchymal transition and act as a coactivator to regulate gene transcription, such as developmental regulator in embryonic stem cells (ESCs) and hypoxia-responsive gene in cancer. The regulation of TETl is also correlated with microRNA in a posttranscriptional modification process. Hence, it is complex but critical to coaprehend the mechanisms of TETI in the biology of ESCs and cancer. Conclusions: TET I not only serves as a demethylation enzyme but also plays multiple roles during tumorigenesis and progression. More studies should be carried out to elucidate the exact mechanisms of TETI and its associations with cancer betbre considering it as a therapeutic tool. 展开更多
关键词 5-hydroxymethylcytosine 5-methylcytosine Embryonic Stem Cells HYPOXIA MicroRNA Ten-eleven TranslocationProteins
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Isolation and chemotaxonomic significance of stenine- and stemoninine-type alkaloids from the roots of Stemona tuberosa 被引量:6
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作者 Rong-Rong Zhang Hai-Yan Tian +4 位作者 Yi Wu xiao-hui sun Jian-Long Zhang Zhi-Guo Ma Ren-Wang Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第9期1252-1255,共4页
One new stenine-type alkaloid, tuberostemonine D (1), together with five known stenine-type alkaloids (2-6) and two known stemoninine-type alkaloids (7 and 8), were isolated from the roots of Stemona tuberosa. T... One new stenine-type alkaloid, tuberostemonine D (1), together with five known stenine-type alkaloids (2-6) and two known stemoninine-type alkaloids (7 and 8), were isolated from the roots of Stemona tuberosa. Their structures were elucidated by extensive spectroscopic methods (IR, UV, MS, 1D and 2D NMR), and the structure of I was further confirmed by X-ray diffraction analysis. First simultaneous isolation ofstenine- and stemoninine-type alkaloids not only added a new chemical type and increased the chemical diversity of Stemona tuberosa, but also provided chemotaxonomic clues for the close relationship between genera Stemona and Stichoneuron, and favored retaining them in the same family. 展开更多
关键词 Sternona tuberosa ALKALOID Tuberostemonine-type
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Theoretical investigations on the thiol–thioester exchange steps of different thioesters
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作者 xiao-hui sun Hai-Zhu Yu +1 位作者 Shu-Qi Pei Zhi-Min Dang 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第10期1259-1264,共6页
As the rate-determining step in native chemical ligation reactions, the thiol–thioester exchange step is important in determining the efficiency of the ligations of peptides. In the present study, systematic theoreti... As the rate-determining step in native chemical ligation reactions, the thiol–thioester exchange step is important in determining the efficiency of the ligations of peptides. In the present study, systematic theoretical calculations were carried out on the relationships between the structure of different thioesters and the free energy barriers of the thiol–thioester exchange step. According to the calculation results, the thiol–thioester exchange step is disfavored by the steric hindrance around the carbonyl center, while the electronic effect(i.e. conjugation and hyper-conjugation effects) becomes important when the steric hindrance is insignificant. 展开更多
关键词 Native chemical ligation Thiol–thioester exchange Density functional theory
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