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Rice SUVH Histone Methyltransferase Genes Display Specific Functions in Chromatin Modification and Retrotransposon Repression

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Molecular Plant 2010年第4期3卷 773-782页

作者： Fu-Jun Qin Qian-Wen Sun Li-Min Huang Xiang-Song Chen Dao-Xiu zhou National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University 430070 Wuhan China Institut de Biotechnologie des Plantes UMR8618 CNRS Universite Paris sud 11 91405 Orsay France

Histone lysine methylation plays an important role in heterochromatin formation and reprogramming of gene expression. SeT-domain-containing proteins are shown to have histone lysine methyltransferase activities. A large number of SeT-domain genes are identified in plant genomes. The function of most SeT-domain genes is not known. In this work, we studied the 12 rice （Oryza sativa） homologs of Su（var）3-9, the histone H3 lysine 9 （H3K9） methyltransferase identified in Drosophila. Several rice SUVHs （i.e. SDG714, SDG727, and SDG710） were found to have an antagonistic func- tion to the histone H3K9 demethylase JMJ706, as down-regulation of these genes could partially complement the jmj706 phenotype and reduced histone H3K9 methylation. Down-regulation of a rice Su（var）3-9 homolog （SUVH）, namely SDG728, decreased H3K9 methylation and altered seed morphology. Overexpression of the gene increased H3K9 methylation. SDG728 and other SUVH genes were found to be involved in the repression of retrotransposons such as Tos17 and a Tyl-copia element. Analysis of histone methylation suggested that SDG728-mediated H3K9 methylation may play an important role in retrotransposon repression.

关键词： Plant histone methyltransferases SeT domain demethylases DNA methylation retrotransposon epigenetic modification rice chromatin.

Numerical Simulation of the Thermal Conductivity of Thermal Insulation Pipeby Vacuum and High Pr essur e Ar gon Pre- filled

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科技视界 2014年第34期 217-218页

作者： zhou Cheng-long XU Yong-xiang SHeNG Hong-zhi Institute of Mechanics Chinese Academy of Sciences

By analyzing the insulation effect of argon-filled tubing and vacuum-insulated tubing before and after hydrogen permeation respectively,a conclusion can be drawn that the insulated tubing filled with high pressure arg... 详细信息

关键词：英语学习学习方法阅读知识阅读材料

Assembly-level analysis on temperature coefficient of reactivity in a graphite-moderated fuel salt reactor fueled with low-enriched uranium

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Nuclear Science and Techniques 2023年第5期34卷 67-84页

作者： Xiao-Xiao Li De-Yang Cui Chun-Yan Zou Jian-Hui Wu Xiang-zhou Cai Jin-Gen Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China CAS Innovative Academy in TMSR energy System Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

To provide a reliable and comprehensive data reference for core geometry design of graphite-moderated and low-enriched uranium fueled molten salt reactors,the influences of geometric parameters on the temperature coefficient of reactivity(TCR)at an assembly level were characterized.A four-factor formula was introduced to explain how different reactivity coefficients behave in terms of the fuel salt volume fraction and assembly *** results show that the fuel salt temperature coefficient(FSTC)is always negative owing to a more negative fuel salt density coefficient in the over-moderated region or a more negative Doppler coefficient in the under-moderated *** on the fuel salt channel spacing,the graphite moderator temperature coefficient(MTC)can be negative or ***,an assembly with a smaller fuel salt channel spacing is more likely to exhibit a negative *** the fuel salt volume fraction increases,the negative FSTC first weakens and then increases,owing to the fuel salt density effect gradually weakening from negative to positive feedback and then ***,the MTC weakens as the thermal utilization coefficient caused by the graphite temperature effect ***,the negative TCR first weakens and then strengthens,mainly because of the change in the fuel salt density *** the assembly size increases,the magnitude of the FSTC decreases monotonously owing to a monotonously weakened fuel salt Doppler coefficient,whereas the MTC changes from gradually weakened negative feedback to gradually enhanced positive ***,the negative TCR ***,to achieve a proper negative TCR,particularly a negative MTC,an assembly with a smaller fuel salt channel spacing in the under-moderated region is strongly recommended.

关键词： Molten salt reactor Temperature coefficient of reactivity Four-factor formula

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皮肤剪切波弹性成像诊断下肢淋巴水肿的探讨

中华显微外科杂志 2024年第4期47卷 382-387页

作者：李家平罗佳李蔓英戚剑周翔李秋霜陈少贞谢晓燕郑艳玲中山大学附属第一医院超声医学科广州510080 中山大学附属第一医院显微创伤手外科广州510080 中山大学附属第一医院康复科广州510080

目的探索淋巴水肿肢体皮肤剪切波弹性成像(SWe)测量的更佳测量模式,并检测其对淋巴水肿的诊断效能。方法2023年8月1日-10日,中山大学附属第一医院超声医学科招募22例健康志愿者,使用导声垫以及厚层耦合剂分别测量肢体皮肤杨氏模量(e-val... 详细信息

目的探索淋巴水肿肢体皮肤剪切波弹性成像(SWe)测量的更佳测量模式,并检测其对淋巴水肿的诊断效能。方法2023年8月1日-10日,中山大学附属第一医院超声医学科招募22例健康志愿者,使用导声垫以及厚层耦合剂分别测量肢体皮肤杨氏模量(e-value)(分别设为GP组和CG组);2023年8月15日-9月28日,连续纳入中山大学附属第一医院显微创伤手外科11例下肢淋巴水肿患者检测13侧水肿肢体皮肤e-value。构建受试者工作特征曲线(ROC)并计算灵敏度、特异度、阳性预测值、阴性预测值以及准确度评估诊断效能。使用SPSS 26.0、R studio以及GraphPad Prism 8软件进行统计分析,采用配对样本非参数检验(Wilcoxon符号秩检验)对比两组间e-value差异,Pearman相关性检验分别分析GP组以及CG组的e-value值相关性。结果远端肢体皮肤的e-value测值均高于相应近端皮肤测值,且以下肢为著。各部位GP组测得e-value值均高于CG组,差异有统计学意义(Pe-value与健康者人群相比较,差异无统计学意义(P>0.01),小腿水肿处皮肤e-value显著增高,差异有统计学意义(Pe-value为27.6 kPa,皮肤厚度增厚截断值为2.3 mm,构建联合诊断模型诊断小腿淋巴水肿的灵敏度、特异度、阳性预测值、阴性预测值以及准确度分别为92.3%、100%、100%、95.7%、97.1%。ROC曲线下面积(AUC)为0.962。GP组与CG组臂、前臂、大腿和小腿皮肤处的e-value的相关系数(R)分别为0.665、0.882、0.850和0.815,均为显著相关。结论使用厚层耦合剂进行皮肤SWe检测的可行性高,联合皮肤SWe以及皮肤厚度两者诊断下肢淋巴水肿的诊断效能较高,可为淋巴水肿早期监测及诊断、显微手术治疗以及围手术期量化评估等提供更加精准的超声影像技术支撑。

关键词：淋巴水肿超声剪切波弹性成像肢体皮肤导声垫

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一种基于交叉熵的黑白棋盘角点检测算法

西北工业大学学报 2015年第2期33卷 216-221页

作者：赵斌 J.Guo e.K.A.Gill 周军西北工业大学精确制导与控制研究所陕西西安710072 Faculty of Aerospace engineering Delft University of TechnologyKluyverweg 12629 HS DelftThe Netherlands

分析了现有黑白棋盘角点检测算法存在的不足,将交叉熵思想引入角点检测中。该算法首先将角点周围像素划分为4个象限,通过相邻象限间的像素灰度差实现角点初选;其次,给出对角象限灰度交叉熵定义,根据局部交叉熵最小原理实现角点筛选;第3... 详细信息

分析了现有黑白棋盘角点检测算法存在的不足,将交叉熵思想引入角点检测中。该算法首先将角点周围像素划分为4个象限,通过相邻象限间的像素灰度差实现角点初选;其次,给出对角象限灰度交叉熵定义,根据局部交叉熵最小原理实现角点筛选;第3,针对备选角点局部重叠的问题,采用梯度幅值非极大值抑制方法实现像素级角点定位;最后采用Frostner算子实现角点的亚像素坐标解算。实验结果显示该算法检测结果优于经典Harris算子以及SV算子,获取的角点亚像素坐标精度与Matlab相机标定工具箱相当,同时易于实现在线标定。

关键词：相机标定棋盘角点检测交叉熵非极大值抑制梯度幅值

Acid dissociation constants and cytotoxicity test of a series of omega-aminoalkyl phosphates

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Chinese Chemical Letters 2016年第9期27卷 1523-1530页

作者： Fu-Hua Sun Yuan-Zhu Long Xiao-Yong zhou Yi-Rou Jiang Xing-Yi Xie Department of Polymeric Biomaterials and Artificial Organs College of Polymer Science and Engineering Sichuan University

We synthesised a series of ω-aminoalkyl sodium hydrogen phosphates （AAP-n-Na, n =3, 4, 5, 6, purity 〉 99%）, which have potential applications as bioactive cosmetic ingredients and surface modifiers of bone minerals （i.e. hydroxyapatites）. Results from Fourier transformed infrared （FTIR）, nuclear magnetic resonance （NMR） and high resolution mass spectroscopy, and elemental analysis all matched their chemical structures. The acid dissociation constants （pKa＇s） of each AAP-n （acid form of AAP-n-Na, n ; 2-6） were measured by potentiometric titration, showing a general increasing trend with an increase in the chain length of AAP-n. However, the pKa3 constant, which corresponds to the deprotonation of the ammonium group in AAP-n-Na, displayed an unusual decrease when n = even. This odd-even effect can be explained by the pairwise self-association of AAP-n-Na molecules in water where intermolecular hydrogen bonding in case of n=even is weaker than that in case of n=odd. All AAP-n-Na at concentrations up to 0.1% （w/v） were non-toxic to L929 fibroblasts and MG 63 osteoblast-like cells in terms of cell growth and morphology, These basic data were important for applications of AAP-n and their salts in biomedical engineering.

关键词： AminoalRyl phosphates Dissociation constant Cytotoxicity Odd-even effect Hydroxyapatite

Philippine retinoblastoma initiative multi-eye center study 2010-2020

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International Journal of Ophthalmology(english edition) 2024年第1期17卷 144-156页

作者： Roland Joseph D.Tan Gary John V.Mercado Patricia e.Cabrera Paulita Pamela P.Astudillo Rolando enrique D.Domingo Josept Mari S.Poblete Charmaine Grace M.Cabebe Adriel Vincent R.Te Melissa Anne S.Gonzales Jocelyn G.Sy Beltran Alexis A.Aclan Jayson T.So Fatima G.Regala Kimberley Amanda K.Comia Josemaria M.Castro Mara Augustine S.Galang Aldous Dominic C.Cabanlas Benedicto Juan e.Aguilar Gabrielle S.evangelista Jo Michael Maniwan Andrei P.Martin Calvin Y.Martinez John Alfred H.Lim Rena Ivy Bascuna Rachel M.Ng Kevin B.Agsaoay Kris Zanna A.Acluba-Arao ellaine Rose V.Apostol Beatriz M.Prieto Department of Ophthalmology and Visual Sciences Philippine General HospitalManila 1000Philippines Department of Ophthalmology Baguio General Hospital and Medical CenterBaguio City 2600Philippines Department of Ophthalmology Manila Doctors HospitalManila 1000Philippines Department of Ophthalmology Rizal Medical CenterPasig City 1600Philippines Department of Ophthalmology Jose B.Lingad Memorial Regional HospitalPampanga 2000Philippines Department of Ophthalmology Southern Philippines Medical CenterDavao City 8000Philippines Department of Ophthalmology East Avenue Medical CenterQuezon City 1100Philippines Department of Ophthalmology Northern Mindanao Medical CenterCagayan de Oro City 9000Philippines Department of Ophthalmology Cebu Velez General HospitalCebu City 6000Philippines Legazpi eye Center Legazpi City 4500Philippines Department of Ophthalmology Cagayan Valley Medical CenterTuguegarao City 3500Philippines

AIM:To provide a comprehensive and more representative national data on the disease,especially on treatment options and outcomes,and to determine access of retinoblastoma patients from Luzon,Visayas and Mindanao to eye care,and determine if access is associated with delay in consultation,staging and ***:Cohort study of retinoblastoma patients seen in eleven institutions located in the three major areas of the Philippines namely Luzon,Vizayas and Mindanao from ***:Totally 636 patients,involving 821 eyes,were ***(57%)were from Luzon and were seen in institutions in Luzon(72%).Annually,58±10 new cases were seen with 71%having unilateral *** delay of consultation remained long at 9(3,17)mo,longest in patients with unilateral disease(Pe from the Visayas(Ped on the International Retinoblastoma Staging System,only 35%of patients had Stage 1 while 47%already had extraocular *** was the most common treatment received by 484 patients while intravenous chemotherapy was received by *** were 250(39%)patients alive,195(31%)dead,85(13%)abandoned,17(3%)refused and 89(14%)with no ***:This study presents the largest cohort of retinoblastoma patients in the Philippines in terms of patients’and participating institutions’number and geographical location and type of institution(private and public).It also presents more comprehensive data on the treatments used and outcomes(survival,globe salvage,and vision retention rates).Delay in consultation was still long among patients leading to advanced disease stage and lower survival *** increasing capacity to diagnose and manage retinoblastoma in the country,the delay of consultation remains long primarily due to accessibility issues to eye care institutions especially in the Visayas and financial *** delay was still significant that overall survival rate remain low.

关键词： retinoblastoma Philippines clinical profile

Polyoxometalates-engineered hydrogen generation rate and durability of Pt/CNT catalysts from ammonia borane

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Journal of energy Chemistry 2020年第2期29卷 142-148页

作者： Wenzhao Fu Chen Han Dali Li Wenyao Chen Jian Ji Gang Qian Weikang Yuan Xuezhi Duan Xinggui zhou State Key Laboratory of Chemical engineering East China University of Science and TechnologyShanghai 200237China Department of Chemical engineering and Applied Chemistry University of TorontoToronto.Ontario M5S 3E5Canada

Heterogeneously catalyzed hydrolytic dehydrogenation of ammonia borane is a remarkable structure sensitive reaction. In this work, a strategy by using polyoxometalates(POMs) as the ligands is proposed to engineer the surface and electronic properties of Pt/CNT catalysts toward the enhanced hydrogen generation rate and durability. Three kinds of POMs, i.e., silicotungstic acid(STA), phosphotungstic acid(PTA)and molybdophosphoric acid(PMA), are comparatively studied, among which the STA shows positive effects on the catalytic activity and durability. A catalyst structure-performance relationship is established by a combination of kinetic and isotopic analyses with multiple characterization techniques, such as HAADF-STeM, eDS, Raman spectroscopy and XPS. It is shown that the STA compared to the other two POMs can increase the Pt binding energy and thus promote the reaction. The insights demonstrated here could open a new avenue for boosting the reaction by employing the POMs as the ligands to engineer the catalyst electronic properties.

关键词： Polyoxometalates Pt/CNT electronic properties Hydrogen generation Durability

The Coupling Constants *** electroweak Model with an SU（4）PS ×SU（4）eW Unification Symmetry

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Communications in Theoretical Physics 2007年第5期47卷 879-882页

作者： A.e. Bernardini Department of Cosmic Rays and Chronology State University of Campinas P.O. Box 6165 13083-970 Campinas SPBrazil

We introduce the sequence of spontaneous symmetry breaking of a coupling between Pati-Salam and electroweak symmetries SU（ 4 ）PS × SU（ 4 ）eW in order to establish a mathematically consistent relation among the coupling constants at grand unification energy scale. With the values of baryon minus lepton quantum numbers of known quarks and leptons, by including right-handed neutrinos, we can lind the mixing angle relations at different energy levels up to the electromagnetic U（1）eM scale.

关键词： electroweak unification gauge symmetry coupling constants