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Chinese Science Bulletin 2007年第6期52卷 855-863页

作者： JIN BiHui liang LiMing Ronald ROUSSEAU leo EGGHE National Science Library Chinese Academy of Sciences Beijing 100080 China Institute for Science Technology and Society Henan Normal University Xinxiang 453002 China University of Antwerp (UA) IBW B-2610 Wilrijk Belgium KHBO Industrial Sciences and Technology B-8400 Oostende Belgium Universiteit Hasselt (UHasselt) Agoralaan B-3590 Diepenbeek Belgium

Based on the foundation laid by the h-index we introduce and study the R- and AR-indices. These new indices eliminate some of the disadvantages of the h-index, especially when they are used in combina-tion with the h-index. The R-index measures the h-core’s citation intensity, while AR goes one step further and takes the age of publications into account. This allows for an index that can actually in-crease and decrease over time. We propose the pair (h, AR) as a meaningful indicator for research evaluation. We further prove a relation characterizing the h-index in the power law model.

关键词： R指数 AR指数 h指数 g指数出版物引文分析

Macro-regenerative nodules in biliary atresia:CT/MRI findings and their pathological relations

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World Journal of Gastroenterology 2008年第28期14卷 4529-4534页

作者： Jiun-Lung liang Yu-Fan Cheng Allan M Concejero Tung-liang Huang Tai-Yi Chen leo Leung-Chit Tsang Hsin-You Ou Departments of Diagnostic Radiology Chang Gung Memorial HospitalKaohsiung Medical Center and Chang Gung University College of Medicine Kaohsiung 83305 Taiwan China Departments of Surgery Chang Gung Memorial Hospital-Kaohsiung Medical Center and Chang Gung University College of Medicine Kaohsiung 83305 Taiwan China

AIM: To describe the radiological findings of a macro-regenerative nodule (MRN) in the liver of pre-transplantation biliary atresia (BA) patients and to correlate it with histological findings. METHODS: Between August 1990 and November 2007, 144 BA patients underwent liver transplantation (LT) at our institution. The pre-transplantation computer tomograghy (CT) and magnetic resonance imaging (MRI) findings were reviewed and correlated with the post-transplantation pathological findings. RESULTS: Nine tumor lesions in 7 patients were diagnosed in explanted livers. The post-transplantation pathological findings showed that all the lesions were MRNs without malignant features. No small nodule was detected by either MRI or CT. Of the 8 detectable lesions, 6 (75%) were in the central part of the liver, 5 (63%) were larger than 5 cm, 5 (63%) had intra- tumor tubular structures, 3 (38%) showed enhancing fibrous septa, 3 (38%) had arterial enhancement in CT, one (13%) showed enhancement in MRI, and one (13%) had internal calcifications. CONCLUSION: Although varied in radiological appearance, MRN can be differentiated from hepatocellular carcinoma (HCC) in most of BA patients awaiting LT. The presence of an arterial-enhancingnodule does not imply that LT is withheld solely on the basis of presumed malignancy by imaging studies. Liver biopsy may be required in aid of diagnostic imaging to exclude malignancy.

关键词： Biliary atresia Macro-regenerative nodule Liver neoplasm Liver transplantation Computed tomography Magnetic resonance imaging

Response of blood endothelin-1 and nitric oxide activity in duodenal ulcer patients undergoing Helicobacter pylori eradication

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World Journal of Gastroenterology 2005年第7期11卷 1048-1051页

作者： Full-Young Chang Chih-Yen Chen Ching-liang Lu Jiing-Chyuan Luo Rei-hwa Lu Shou-Dong Lee Division of Gastroenterology

AIM: To investigate the effect of Helicobacter pylori eradication on endothelin-1 (ET-1) and nitric oxide (NO) in duodenal ulcer (DU) patients. METHODS: Sixty-six Hpylori-infected active DU patients were consecutively enrolled to receive one-week triple therapy (rabeprazole, amoxicillin and metronidazole) and then one-month rabeprazole therapy. They were asked back to determine ulcer and Hpylori status using endoscopy one month later. Thirty-seven healthy controls (H pylori +/-:17/20) were enrolled for comparison. Blood samples were collected in each visit to measure plasma ET-1 and nitrate/nitrite levels using an enzyme immunoassay kit. RESULTS: Sixty DU patients finished trial per protocol. The ulcer healing and Hpylori-eradication rates were 86.7% and 83.3%, respectively. Plasma ET-1 level in DU patients was higher than that of Hpylori-negative and positive controls (3.59±0.96 vs0.89±0.54 vs0.3±0.2 pg/mL,P<0.01), while nitrate/nitrite levels among them were also significantly different (8.55±0.71 vs5.27±0.68 vs 6.39±0.92 μmol/L, P<0.05). H pylori eradication diminished ET-1 levels (3.64±0.55 vs2.64±0.55 pg/mL, P<0.01) but elevated nitrate/ nitrite level (8.16±0.84 vs11.41±1.42 umol/L,P<0.05). CONCLUSION: Both plasma ET-1 and nitrate/nitrite levels increase in active DU patients. After an effective H pylori eradication, DU healing is associated with diminished blood ET-1 level and elevated nitrate/nitrite level.

关键词： Duodenal ulcer Endothelin-1 Helicobacter pylori Nitric oxide

Left-sided gallbladder:Its clinical significance and imaging presentations

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World Journal of Gastroenterology 2007年第47期13卷 6404-6409页

作者： Sheng-Lung Hsu Tai-Yi Chen Tung-liang Huang Cheuk-Kwan Sun Allan M Concejero leo Leung-Chit Tsang Yu-Fan Cheng Department of Diagnostic Radiology Chang Gung Memorial Hospital - Kaohsiung Medical Center Chang Gung University College of Medicine Kaohsiung Taiwan China Department of Surgery Chang Gung Memorial Hospital - Kaohsiung Medical Center Chang Gung University College of Medicine Kaohsiung Taiwan China

AIM: To assess the importance of preoperative diagnosis and presentation of left-sided gallbladder using ultrasound (US),CT and angiography. METHODS: Retrospective review of 1482 patients who underwent enhanced CT scanning was performed. Left-sided gallbladder was diagnosed if a right-sided ligamentum teres was present. The image presentations on US,CT and angiography were also reviewed. RESULTS: Left-sided gallbladder was diagnosed in nine patients. The associated abnormalities on CT imaging included portal vein anomalies,absence of umbilical portion of the portal vein in the left lobe of the liver,club-shaped portal vein in the right lobe of the liver,and difficulty in identifying segment Ⅳ. Angiography in six of nine patients demonstrated abnormal portal venous system (trifurcation type in four of six patients). The main hepatic arteries followed the portal veins in all six patients. The segment Ⅳ artery was identified in four of six patients using angiography,although segment Ⅳ was difficult to define on CT imaging. Hepatectomy was performed in three patients with concomitant liver tumor and the diagnosis of left-sided gallbladder was confirmed intraoperatively. CONCLUSION: Left-sided gallbladder is an important clinical entity in hepatectomy due to its associated portal venous and biliary anomalies. It should be considered in US,CT and angiography images that demonstrate no definite segment Ⅳ,absence of umbilical portion of the portal vein in the left lobe,and club-shaped right anterior portal vein.

关键词： Left-sided gallbladder Angiography Computed tomography Ultrasound

智能高速铁路中基于低轨卫星网络的通信关键技术研究

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铁道学报 2024年第8期46卷 69-77页

作者：张嘉驰刘留周涛蔺伟梁轶群山东警察学院警务信息系山东济南250200 北京交通大学电子信息工程学院北京100044 中国铁道科学研究院集团有限公司通信信号研究所北京100081

智能高速铁路是构建现代综合交通运输体系的重要组成部分,建立支持高移动性、高速率、高可靠性、高实时性的通信链路是列车安全运行的基石。针对高速铁路空间跨度范围大、轨旁通信设备成本高、越区切换频繁等问题,探讨基于低轨卫星互联... 详细信息

智能高速铁路是构建现代综合交通运输体系的重要组成部分,建立支持高移动性、高速率、高可靠性、高实时性的通信链路是列车安全运行的基石。针对高速铁路空间跨度范围大、轨旁通信设备成本高、越区切换频繁等问题,探讨基于低轨卫星互联网技术实现车地通信的可能性及关键技术。分析智能高速铁路通信业务需求并根据不同的业务类型采用对应的专网或公网进行承载。研究了基于公网卫星互联网络的高速铁路无线接入架构。并在此基础上进一步探讨了面向智能高速铁路的卫星接入与低时延传输、星地链路多普勒频偏、星内/间波束切换等关键技术,以期实现低时延、高可靠的星地通信链路。

关键词：智能高速铁路低轨卫星网络无线接入低时延传输多普勒频偏波束切换

5-Methylcytosine RNA Methylation in Arabidopsis Thaliana

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Molecular Plant 2017年第11期10卷 1387-1399页

作者： Xuean Cui Zhe liang Lisha Shen Qian Zhang Shengjie Bao Yuke Geng Bin Zhang Vonny leo Leah A. Vardy Tiegang Lu Xiaofeng Gu Hao Yu Biotechnology Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 China Department of Biological Sciences and Temasek Life Sciences Laboratory National University of Singapore 117543 Singapore Singapore Institute of Medical Biology Agency for Science Technology and Research (A^+STAR) 8A Biomedical Grove #06-06 Immunos 138648 Singapore Singapore

5-Methylcytosine （m^5C） is a well-characterized DNA modification, and is also predominantly reported in abundant non-coding RNAs in both prokaryotes and eukaryotes. However, the distribution and biological functions of m^5C in plant mRNAs remain largely unknown. Here, we report transcriptome-wide profiling of RNA m^5C in Arabidopsis thaliana by applying m^5C RNA immunoprecipitation followed by a deep- sequencing approach （m^5C-RIP-seq）. LC-MS/MS and dot blot analyses reveal a dynamic pattern of m^5C mRNA modification in various tissues and at different developmental stages, m^5C-RIP-seq analysis identified 6045 m^5C peaks in 4465 expressed genes in young seedlings. We found that m^5C is enriched in coding sequences with two peaks located immediately after start codons and before stop codons, and is associated with mRNAs with low translation activity. We further demonstrated that an RNA （cytosine-5）-methyl- transferase, tRNA-specific methyltransferase 4B （TRM4B）, exhibits m^5C RNA methyltransferase activity. Mutations in TRM4B display defects in root development and decreased m^5C peaks. TRM4B affects the transcript levels of the genes involved in root development, which is positively correlated with their mRNA stability and m^5C levels. Our results suggest that m^5C in mRNA is a new epitranscriptome marker inArabidopsis, and that regulation of this modification is an integral part of gene regulatory networks underlying plant development.

关键词： 5-methylcytosine (m^5C) Arabidopsis RNA methylation TRM4B root development

面向低轨卫星通信的低复杂度CA-SCL译码优化算法

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中国科学院大学学报（中英文） 2024年第5期41卷 715-720页

作者：胡修齐侯缋玲梁广余金培中国科学院微小卫星创新研究院上海201210 上海科技大学上海201210

基于硬件资源有限的低轨卫星通信环境,以极化码作为信道编码方式,将循环冗余校验(CRC)辅助连续取消列表(SCL)译码器(CRC aided SCL,CA-SCL)结合关键集以及自适应算法,提出一种优化的CA-SCL译码器(optimized CA-SCL,OCASCL),该译码器的... 详细信息

基于硬件资源有限的低轨卫星通信环境,以极化码作为信道编码方式,将循环冗余校验(CRC)辅助连续取消列表(SCL)译码器(CRC aided SCL,CA-SCL)结合关键集以及自适应算法,提出一种优化的CA-SCL译码器(optimized CA-SCL,OCASCL),该译码器的译码性能优于经典CA-SCL译码器,运算复杂度可降低65%~70%。

关键词：低轨卫星通信极化码 CA-SCL 关键集低译码复杂度

Sensor management of leo constellation based on covariance control

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Journal of Systems Engineering and Electronics 2019年第2期30卷 393-401页

作者： QIN Zheng liang Yan'gang College of Aerospace Science and Engineering National University of Defense Technology

This paper studies the multi-sensor management problem for low earth orbit(leo) infrared warning constellation used to track a midcourse missile. A covariance control approach, which selects sensor combinations or subset based on the difference between the desired covariance matrix and the actual covariance of each target, is used for sensor management, including some matrix metrics to measure the differentia between two covariance matrices. Besides, to meet the requirements of the space based warning system, the original covariance control approach is improved. Simulation results demonstrate that the covariance control approach is able to provide a better tracking performance by providing a well-designed desired covariance and balance tracking performance goals with system demands.

关键词： sensor management covariance control target tracking accuracy leo constellation

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高兼容性亚码元级激光通信/测距一体化系统

红外与激光工程 2024年第8期53卷 186-193页

作者：翟政豪王宜州黎景王亮戴潇潇刘陈杨奇华中科技大学光学与电子信息学院湖北武汉430074 金银湖实验室湖北武汉430040

随着全社会的数字化转型,空天地一体化信息网络被迅速布局,对卫星间的多调制格式的高速相干光通信和高精度测距的需求愈加迫切。基于相干光通信,提出了一种低成本、低复杂度、高精度的通信/测距一体化系统,通过在相干光通信系统中间隔... 详细信息

随着全社会的数字化转型,空天地一体化信息网络被迅速布局,对卫星间的多调制格式的高速相干光通信和高精度测距的需求愈加迫切。基于相干光通信,提出了一种低成本、低复杂度、高精度的通信/测距一体化系统,通过在相干光通信系统中间隔插入特定的测距数据帧,并利用改进的并行数字时钟恢复(CDR)算法,由其中的鉴相模块提取相位偏差信息,无需消耗额外的硬件资源即可实现高精度测距,由此满足卫星上低功耗、低重量和小尺寸的需求。此外,该系统可兼容不同相干光调制格式,包括OOK、BPSK和QPSK以及不同传输速率的相干光通信链路,体现出了高兼容性。提出的系统在现场可编程门阵列(FPGA)上进行实验验证,在625 Mbps和1 Gbps的BPSK信号下进行通信/测距实验。实验结果表明,码元持续时间为1.6 ns和1 ns,测距精度达到码元时长的2.25%和4.74%,测距精度分别为11 mm和14 mm,达到亚码元量级。通过所提出的通信/测距一体化系统,解决了现有测距系统通用性较差,复杂度较高的问题,提升了系统的灵活性。

关键词： FPGA 时钟恢复高精度测距相干光通信