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Quantitative assessment of hepatic fibrosis in chronic hepatitis B and C: T1 mapping on Gd-EOB-DTPA-enhanced liver magnetic resonance imaging

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World Journal of Gastroenterology 2018年第18期24卷 2024-2035页

作者： shen Pan Xiao-qi Wang qi-yong Guo Department of Radiology Shengjing Hospital of China Medical University Department of Clinical Science Philips Health-care

AIM To assess the accuracy of Look-Locker on gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(GdEOB-DTPA)-enhanced magnetic resonance imaging(MRI) for staging liver fibrosis in chronic hepatitis B/C(CHB/C).METHODS We prospectively included 109 patients with CHB or CHC who underwent a 3.0-Tesla MRI examination, including T1-weighted and Look-Locker sequences for T1 mapping. Hepatocyte fractions(He F) and relaxation time reduction rate(RE) were measured for staging liver fibrosis. A receiver operating characteristic analysis using the area under the receiver operating characteristic curve(AUC) was used to compare thediagnostic performance in predicting liver fibrosis between He F and *** A total of 73 patients had both pathological results and MRI information. The number of patients in each fibrosis stage was evaluated semiquantitatively according to the METAVIR scoring system: F0, n = 23(31.5%); F1, n = 19(26.0%); F2, n = 13(17.8%); F3, n = 6(8.2%), and F4, n = 12(16.4%). He F by EOB enhancement imaging was significantly correlated with fibrosis stage(r =-0.808, P < 0.05). AUC values for diagnosis of any(≥ F1), significant(≥ F2) or advanced(≥ F3) fibrosis, and cirrhosis(F4) using He F were 0.837(0.733-0.913), 0.890(0.795-0.951), 0.957(0.881-0.990), and 0.957(0.882-0.991), respectively. He F measurement was more accurate than use of RE in establishing liver fibrosis staging, suggesting that calculation of He F is a superior noninvasive liver fibrosis staging *** A T1 mapping-based He F method is an efficient diagnostic tool for the staging of liver fibrosis.

关键词： Liver fibrosis Gd-EOB-DTPA Look-Locker hepatocyte fraction liver function magnetic resonance imaging relative enhancement

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The regulatory network mediated by circadian clock genes is related to heterosis in rice

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Journal of Integrative Plant Biology 2015年第3期57卷 300-312页

作者： Guojing shen Wei Hu Bo Zhang Yongzhong xing National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan) Huazhong Agricultural University

Exploitation of heterosis in rice（Oryza sativa L.） has contributed greatly to global food *** this study,we generated three sets of reciprocal F1 hybrids of indica and japonica subspecies to evaluate the relationship between yield heterosis and the circadian *** were no differences in trait performance or heterosis between the reciprocal hybrids,indicating no maternal effects on *** indica-indica and indica-japonica reciprocal F1 hybrids exhibited pronounced heterosis for chlorophyll and starch content in leaves and for grain yield/*** contrast,the japonica-japonica F1 hybrids showed low *** three circadian clock genes investigated expressed in an above-high-parent pattern（AHP）at seedling stage in all the *** five genes downstream of the circadian clock,and involved in chlorophyll and starch metabolic pathways,were expressed in AHP in hybrids with strong better-parent heterosis（BPH）.Similarly,three of these Research Arfive genes in the japonica-japonica F1 hybrids showing low BPH were expressed in positive overdominance,but the other two genes were expressed in additive or negative *** results indicated that the expression patterns of circadian clock genes and their downstream genes are associated with heterosis,which suggests that the circadian rhythm pathway may be related to heterosis in rice.

关键词： Circadian clock better-parent heterosis biomass overdominance yield

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Cooling Rates of PREP Ti48Al Alloy

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Journal of Materials Science & Technology 2001年第1期17卷 91-92页

作者： Xuezhu MA Jun shen Xiumei qi Jun JIA School of Materials Science&Engineering Harbin institute of TechnologyHarbin 150001China

Determining the cooling rate of a rapidly-solidified (RS) technique subjectively is a prerequisite of knowing the RS technique, and it is difficult. Model of heat transfer is constructed in this paper in order to calculate cooling rates of rapidly-solidified Ti48AI alloy. Rapid solidification technique utilized is the plasma rotating electrode process (PREP hereafter). The results show that: the cooling rate of PREP is at the scope of 102-103 K/s.

关键词： cooling rate electrode process heat transfer RS technique in order

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Blockchain-based Privacy-Preserving Group Data Auditing with Secure User Revocation

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Computer Systems Science & Engineering 2023年第4期45卷 183-199页

作者： Yining qi Yubo Luo Yongfeng Huang xing Li Tsinghua University Beijing100084China Beijing National Research Center for Information Science and Technology Beijing100084China University of North Carolina at Chapel Hill North Carolina27599USA

Progress in cloud computing makes group data sharing in outsourced storage a *** join in group and share data with each other,making team work more *** new application scenario also faces data security threats,even more *** a user quit its group,remaining data block signatures must be re-signed to ensure *** researchers noticed this problem and proposed a few works to relieve computing overhead on user ***,considering the privacy and security need of group auditing,there still lacks a comprehensive solution to implement secure group user revocation,supporting identity privacy preserving and collusion attack *** at this target,we construct a concrete scheme based on ring signature and smart *** introduce linkable ring signature to build a kind of novel meta data for integrity proof enabling anonymous *** the new meta data supports secure ***,smart contracts are using for resisting possible collusion attack and malicious re-signing *** the combined effectiveness of both signature method and blockchain smart contracts,our proposal supports reliable user revocation and signature re-signing,without revealing any user identity in the whole *** and performance analysis compared with previous works prove that the proposed scheme is feasible and efficient.

关键词： Provable data possession data integrity blockchain ring signature

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Research on low carbon management using a scientific classification method

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Frontiers of Environmental Science & Engineering 2012年第4期6卷 524-530页

作者： Shanna qi Meiting JU Meng DUAN Wei xing Department of Environmental Science and Engineering Nankai UniversityTianjin 300071China

This research is aimed at the rapid development of a low-carbon economy, in which we propose the classification and application of relevant management measures to affect the development of environmental management ideas and measures of the low-carbon economy, which we called as low carbon management measures. According to scientific analysis of the lowcarbon economy, we can divide low-carbon management measures into three parts： measures for reduction of carbon sources, carbon flow planning, and increase of carbon sinks. Furthermore, we list the advantages that China can utilize to develop its own low-carbon management measures. In the end, necessary adjustments to environmental management measures in China can be made according to this scientific classification.

关键词： low-carbon economy low carbon manage- ment carbon source carbon flow carbon sink

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Sr-Nd-Pb isotopes of Tertiary volcanics of King George Island, Antarctica

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Chinese Science Bulletin 1997年第22期42卷 1913-1918页

作者： xing, GF shen, WZ Wang, DZ Jin, QM Nanjing Inst Geol & Mineral Resources Nanjing 210016 Peoples R China

1 Geological settingThe King George Island is the largest one in South Shetland Islands, West Antarctica,with an area of 1200 km^2. Most of it is covered by ice and snow all the year round. It consistsmainly of Tertia... 详细信息

关键词： Sr-Nd-Pb isotopes Tertiary volcanics King George Island Antarctica.

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Service behavior modeling and service behavior convergence-based radio resource scheduling in wireless systems

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 52-58,88页

作者： CAI Wen-qi ZHANG xing WANG Wen-bo School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

With the development of wireless networks, the amount of multiple services increased sharply in recent years. High quality multiple services with low price are urgently needed especially in new generation mobile communication systems, e.g., 3G/LTE networks. It is important to enhance the availability of data service resources. Services have strong association which are used by clients with similar behavior habits in networks. Such feature results in service behavior convergence （SBC） and its utilization will enhance resource efficiency. This paper proposes two applications of service behavior： service prediction and a scheduling algorithm which enhances bandwidth efficiency. Convergence cells are classified according to SBC and hot-spot services are broadcasted separately in each convergence cell. It is demonstrated by stimulation that the bandwidth is saved 80% more than classical cellular system and nearly 20% more than traditional broadcasting system.

关键词： service behavior service prediction improved Apriori algorithm service behavior convergence

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BMA probability quantitative precipitation forecasting of land-falling typhoons in south-east China

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Frontiers of Earth Science 2019年第4期13卷 758-777页

作者： Linna ZHAO Xuemei BAI Dan qi Cheng xing Chinese Academy of Meteorological Sciences Beijing 100081China Heilongjiang Meteorological Observatory Harbin 150001China National Meteorological Centre Beijing 100081China Heilongjiang Mulan County Meteorological Observatory Mulan 151900China

The probability of quantitative precipitation forecast(PQPF)of three Bayesian Model Averaging(BMA)models based on three raw super ensemble prediction schemes(i.e.,A,B,and C)are established,which through calibration of their parameters using 1-3 day precipitation ensemble prediction systems(EPSs)from the China Meteorological Administration(CMA),the European Centre for Medium-Range Weather Forecasts(ECMWF)and the National Centers for Environmental Prediction(NCEP)and observation during land-falling of three typhoons in south-east China in *** comparison of PQPF shows that the performance is better in the BMA than that in raw ensemble *** average,the mean absolute error(MAE)of 1 day lead time forecast is reduced by 12.4%,and its continuous ranked probability score(CRPS)of 1-3 day lead time forecast is reduced by 26.2%,*** the amount of precipitation prediction by the BMA tends to be underestimated,but in view of the perspective of probability prediction,the probability of covering the observed precipitation by the effective forecast ranges of the BMA are increased,which is of great significance for the early warning of torrential rain and secondary disasters induced by it.

关键词： Bayesian model averaging probabilistic quantitative precipitation forecasting ensemble prediction typhoon precipitation

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Formation of the CME Leading Edge Observed in the 2003 February 18 Event

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Chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 741-750页

作者： xing-Ming Bao Hong-qi Zhang Jun Lin National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Harvard-Smithsonian Center for Astrophysics 60 Garden Street Cambridge MA 02138 USA

This work investigates a typical coronal mass ejection （CME） observed on 2003 February 18, by various space and ground instruments, in white light, Ha, EUV and X- ray. The Ha and EUV images indicate that the CME started with the eruption of a long filament located near the solar northwest limb. The white light coronal images show that the CME initiated with the rarefaction of a region above the solar limb and followed by the formation of a bright arcade at the boundary of the rarefying region at height 0.46 Re above the solar surface. The rarefying process synchronized with the slow rising phase of the eruptive filament, and the CME leading edge was observed to form as the latter started to accelerate. The lower part of the filament brightened in Ha as the filament rose to a certain height and parts of the filament was visible in the GOES X-ray images during the rise. These brightenings imply that the filament may be heated by the magnetic reconnection below the filament in the early stage of the eruption. We suggest that a possible mechanism which leads to the formation of the CME leading edge and cavity is the magnetic reconnection which takes place below the filament after the filament has reached a certain height.

关键词： Sun coronal mass ejections (CMEs) - Sun filaments - Sun flares

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Discussion on the PGE anomalies and source materials of K-bentonite(Bed 5) in the Lower Cambrian Meishucun section, Yunnan

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Chinese Journal Of Geochemistry 2015年第3期34卷 346-361页

作者： Lecai xing Mingzhong Zhou Liang qi Zhilong Huang State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences School of Geographical and Environmental Sciences Guizhou Normal University

The Meishucun section in Yunnan is the stratotype section for stratigraphic correlation of the Lower Cambrian strata across the Yangtze Block. Known for enriched small shelly fossils, it is a prominent section for investigating the Early Cambrian phosphogenic ***ˇava et al.(Econ Geol 105:1047–1056, 2010) reported anomalously high PGE concentrations in this section, up to576 9 10-9(434 9 10-9Pt, 142 9 10-9Pd) for the total PGE concentrations of a K-bentonite sampled from the bottom of Bed 5. This finding can illustrate two significant statements:(1) in addition to the attested polymetallic NiMo-PGE ore layer, another potential PGE enrichment layer exists with PGE concentrations up to the mineralization level; and(2) acid volcanics have high PGE contents overturning conventional views. To inspect whether the anomalous PGE concentration is pervasive, we investigated Bed 5 of the Meishucun section systematically, and sampled from a profile with a thickness of 3.5 m. The major and trace element geochemistry indicate the Bed5 K-bentonite is derived from acid volcanic ash. PGE concentrations were determined repeatedly by isotope dilution-ICP-MS using improved digestion technique(qi et al., in J Anal At Spectrom 26:1900–1904, 2011), and were duplicated by fire assay method. The results showed that each sample had total PGE concentrations of less than0.90 9 10-9, and Pt ? Pd concentrations of no higher than0.70 9 10-9. Combined with the petrological and mineralogical features, and trace and rare earth element analyses,it is inferred that no generality of PGE enrichment exists in Bed 5 and that the anomalous PGE concentration is likely due to the nugget effect of volcanic ash modified by currents in a shallow coastal environment.

关键词：元素异常下寒武统膨润土剖面梅树铂族云南酸性火山岩

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