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AN ALABASTER SCULPTED HEADOFPTOLEMY V FROM THE PUSHKIN MUSEUMOFFINEARTS,MOSCOW,ANDHORUSASPECTS OF LATE PERIOD EGYPTIAN AND PTOLEMAIC KINGSHIP
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作者 Ivan A.Ladynin 《Journal of Ancient Civilizations》 2023年第1期1-20,125,共21页
The typology of Ptolemaic royal sculpture has served as a theme of research for a number of scholars who have managed to achieve impressive results:two fundamental works must be mentioned.The earlier is Bildnisse der ... The typology of Ptolemaic royal sculpture has served as a theme of research for a number of scholars who have managed to achieve impressive results:two fundamental works must be mentioned.The earlier is Bildnisse der Ptolemaer by H.Kyrieleis,which established a convincing correspondence between the well-attributed images of the Ptolemaic kings on their coins and their mostly uninscribed sculpted images.'The history of the research reveals that although the corpus of Ptolemaic sculpture gradually expanded,due to new finds and new publications,challenges to specific attributions proposed by Kyrieleis often proved to be a failure?A later work deserving a special mention is Portraits of the Ptolemies by P.E.Stanwick,which proposed a well-founded scheme for the evolution of the Ptolemaic royal sculpture dividing it into nine groups(Groups A-E,G making a chronological sequence,Groups F,H-J uncertain and miscellaneous)'Quite expectedly,a problematic issue is the ultimate motive and final result of shifting from one such group to another:a grouping of objects is largely a formal task,and a scholar performing it is unlikely to concentrate simultaneously on the variety of political,ideological,and religious factors that could lie behind the emergence of the groups indicated.The present article aims to offer a tentative explanation for the shift in the style of Ptolemaic sculpture that took place at the cusp of the 3rd and 2nd centuries BC,i.e.,the transition between Stanwick's "Group A"and "Group B." 展开更多
关键词 dividing RELIGIOUS SHIFTING
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Unrelaxed State in Epitaxial Heterostructures Based on Lead Selenide 被引量:3
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作者 Arif Pashaev Omari Davarashvili +3 位作者 Zaira Akhvlediani Megi Enukashvili Revaz Gulyaev Vladimir Zlomanov 《Journal of Modern Physics》 2012年第6期502-510,共9页
The work deals with the epitaxial PbSe layers grown on the KCl substrates by the method of “hot-wall” molecular epitaxy over the range of layer thicknesses of 20 - 2000 nm. Special emphasis is put on the values of e... The work deals with the epitaxial PbSe layers grown on the KCl substrates by the method of “hot-wall” molecular epitaxy over the range of layer thicknesses of 20 - 2000 nm. Special emphasis is put on the values of elastic deformations that could be generated and frozen in epitaxial layers with the aim of influencing their energy spectra and optical properties. The maximum deformation at layers tension made up 57% of the initial mismatch between the layer and the substrate (ε = Δa/a = 0.015). In such a solid-state structure effective “negative” pressure is realized, which is justified by increase in the tangential lattice constant and the forbidden gap width. This width correlates with the tangential lattice constant (deformation) and corresponds to certain values of definite frequencies of direct electron transitions across the forbidden gap. 展开更多
关键词 MISMATCH LATTICE Constant STRAINED Layer Unrelaxed STATE Effective “Negative” Pressure Optical Characterization
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Nitrogen-Doped Chemical Vapour Deposited Diamond: a New Material for Room-Temperature Solid State Maser
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作者 N. A. Poklonski N. M. Lapchuk +6 位作者 A. V. Khomich 吕反修 唐伟忠 V. G. Ralchenko I. I. Wlasov M. V. Chukichev Sambuu Munkhtsetseg 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第7期2088-2090,共3页
在 dcarc 喷气和微波血浆化学药品蒸汽免职种的多晶的钻石电影的电子旋转回声(ESR ) 被学习。有直到 8 x 10 的氮杂质集中(18 ) 的电影厘米(-3) 被拉曼,阴极射线发光和光吸收也描绘系列。从有 2.0024 的 g 因素(在钻石格子的氮杂质原... 在 dcarc 喷气和微波血浆化学药品蒸汽免职种的多晶的钻石电影的电子旋转回声(ESR ) 被学习。有直到 8 x 10 的氮杂质集中(18 ) 的电影厘米(-3) 被拉曼,阴极射线发光和光吸收也描绘系列。从有 2.0024 的 g 因素(在钻石格子的氮杂质原子占据 C 地点) 的 P1 中心的 ESR 信号被发现与在一个 H-102 共鸣器增加微波力量展出倒置。当微波激射的媒介在房间温度操作了,旋转倒置效果能具有为做 N 的钻石的进一步的考虑的兴趣。 展开更多
关键词 氮元素 化学 杂质 沉淀物 微波激射器
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Quick and Simple Spectrophotometric Method of Identification of the Thermal State of Meat on the Basis of Composition and Content of Free Nucleotides
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作者 Magomed Dibirasulaev Georgy Belozerov +1 位作者 Leonid Arkhipov Lidia Stoyanova 《Food and Nutrition Sciences》 2018年第5期572-583,共12页
At present, there is no method for identifying meat frozen in a thermal state acceptable for production control. The role of free nucleotides in the processes of refrigeration and storage of meat, affecting the struct... At present, there is no method for identifying meat frozen in a thermal state acceptable for production control. The role of free nucleotides in the processes of refrigeration and storage of meat, affecting the structural and mechanical properties of muscle tissue, the formation of taste and its biological value is known. In this article we compared methods for identifying the thermal state of meat based on the determination of the composition and content of free nucleotides by high-performance liquid chromatography (HPLC) and spectrophotometry [SF]. High-purity reference substances were used: free nucleotides—ATP, ADP, AMP, IMP and nucleosides-inosine and hypoxanthine. It has been experimentally established that the characteristic peaks of the absorption spectra for extracts of free nucleotides of meat frozen depended from thermal state of meat. The content of ATP is 21.8 times higher in meat frozen in a fresh state, and the amount of IMF is 12.3 times lower than in meat frozen after cooling. The results of studies of meat frozen using the HPLC method and the developed SF method show the adequacy of the data obtained by both methods. SF-method based on the determination of the optical density of the extracts of free nucleotides is recommended to justify the choice of technological process meat defrost modes. 展开更多
关键词 Thermal State of MEAT Free NUCLEOTIDES and NUCLEOSIDES HPLC and SPECTROPHOTOMETRIC Methods Defrost MODES
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日轮果属,越南唇形科黄芩亚科一新属
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作者 李波 Thanh Son HOANG +4 位作者 Maxim S.NURALIEV Vu Anh TAI Andrey N.KUZNETSOV Svetlana P.KUZNETSOVA 向春雷 《热带亚热带植物学报》 CAS CSCD 北大核心 2023年第5期727-735,共9页
描述并绘制了越南唇形科一新属及新种:日轮果属(Heliacria Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)和日轮果(H.maritima Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)。日轮果属因具攀援藤本习性,花大且花冠为纯白色,花萼近辐射对称、5... 描述并绘制了越南唇形科一新属及新种:日轮果属(Heliacria Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)和日轮果(H.maritima Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)。日轮果属因具攀援藤本习性,花大且花冠为纯白色,花萼近辐射对称、5深裂、裂片长且在果期增大并开展,果实顶端具放射状的瘤状突起等特征而明显区别于黄芩亚科的其他5属。目前,该属仅发现于越南东南部沿海的平定省、富安省、庆和省和宁顺省,常生于海岸边干旱的低地矮林中。 展开更多
关键词 新分类群 特有属 冬红属 膜萼藤属 唇形目
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Identification of a three-gene prognostic signature for radioresistant esophageal squamous cell carcinoma
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作者 Xiao-Yan Wang Narasimha M Beeraka +6 位作者 Nan-Nan Xue Hui-Ming Yu Ya Yang Mao-Xing Liu Vladimir N Nikolenko Jun-Qi Liu Di Zhao 《World Journal of Clinical Oncology》 CAS 2023年第1期13-26,共14页
BACKGROUND Esophageal squamous cell carcinoma(ESCC)is causing a high mortality rate due to the lack of efficient early prognosis markers and suitable therapeutic regimens.The prognostic role of genes responsible for t... BACKGROUND Esophageal squamous cell carcinoma(ESCC)is causing a high mortality rate due to the lack of efficient early prognosis markers and suitable therapeutic regimens.The prognostic role of genes responsible for the acquisition of radioresistance in ESCC has not been fully elucidated.AIM To establish a prognostic model by studying gene expression patterns pertinent to radioresistance in ESCC patients.METHODS Datasets were obtained from the Gene Expression Omnibus and The Cancer Genome Atlas databases.The edgeR,a Bioconductor package,was used to analyze mRNA expression between different groups.We screened genes specifically responsible for radioresistance to estimate overall survival.Pearson correlation analysis was performed to confirm whether the expression of those genes correlated with each other.Genes contributing to radioresistance and overall survival were assessed by the multivariate Cox regression model through the calculation ofβi and risk score using the following formula:∑^(n)_(i=1)βi×PSI.RESULTS We identified three prognostic mRNAs(cathepsin S[CTSS],cluster of differentiation 180[CD180],and SLP adapter and CSK-interacting membrane protein[SCIMP])indicative of radioresistance.The expression of the three identified mRNAs was related to each other(r>0.70 and P<0.05).As to 1-year and 3-year overall survival prediction,the area under the time-dependent receiver operating characteristic curve of the signature consisting of the three mRNAs was 0.716 and 0.841,respectively.When stratifying patients based on the risk score derived from the signature,the high-risk group exhibited a higher death risk and shorter survival time than the low-risk group(P<0.0001).Overall survival of the low-risk patients was significantly better than that of the highrisk patients(P=0.018).CONCLUSION We have developed a novel three-gene prognostic signature consisting of CTSS,CD180,and SCIMO for ESCC,which may facilitate the prediction of early prognosis of this malignancy. 展开更多
关键词 Esophageal squamous cell carcinoma CTSS CD180 SCIMP RADIORESISTANCE TNM stage PROGNOSIS
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荧光偏振免疫分析方法快速检测沙拉沙星残留 被引量:16
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作者 宋佩 孟萌 +6 位作者 Sergei A Eremin 张太昌 田溪 薛虎寅 张昱 尹永梅 郗日沫 《分析化学》 SCIE EI CAS CSCD 北大核心 2012年第8期1247-1251,共5页
以异硫氰酸荧光素(FITC)标记沙拉沙星合成荧光标记物,采用薄层色谱法提纯,优化了反应时间、标记物和抗体的工作浓度,建立了沙拉沙星的快速荧光偏振免疫分析法(FPIA)。本方法测定沙拉沙星在缓冲液中的半数抑制浓度(IC50)为43.2μg/L;检... 以异硫氰酸荧光素(FITC)标记沙拉沙星合成荧光标记物,采用薄层色谱法提纯,优化了反应时间、标记物和抗体的工作浓度,建立了沙拉沙星的快速荧光偏振免疫分析法(FPIA)。本方法测定沙拉沙星在缓冲液中的半数抑制浓度(IC50)为43.2μg/L;检测范围为5.7~327μg/L,可以达到国家规定的动物性食品中兽药最高残留限量(80μg/kg)的要求。本研究考察了FPIA测定沙拉沙星的动力学过程及对其它4种喹诺酮类药物的交叉反应。结果表明,环丙沙星、恩诺沙星、加替沙星及氧氟沙星的交叉反应率分别为3.3%,1.8%,1.7%和0.7%。在牛奶和猪尿中沙拉沙星的回收率分别在71%~94%和74%~102%之间。本方法操作简单快捷,整个检测过程只需5 min、而且灵敏度较高、特异性强,适用于动物性食品中沙拉沙星残留的快速筛选检测。 展开更多
关键词 荧光偏振免疫分析 沙拉沙星 喹诺酮类药物 荧光标记
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大鼠离体作功心脏对冠脉压强变化的反应
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作者 张游 张秋实 +2 位作者 韩宝莲 李玉明 刘东海 《中国医学物理学杂志》 CSCD 2004年第6期341-342,350,共3页
目的:研究离体作功心脏对其冠脉压强变化的反应。方法:采用分离式离体作功心脏模型。用上海产SJ-42型四导生理记录仪测定生理参数左心室收缩压LVSP,左心室内压上升的最大速率(dp/dt)max,冠脉流量CF,心率HR和心电图ECG。结果:离体作功心... 目的:研究离体作功心脏对其冠脉压强变化的反应。方法:采用分离式离体作功心脏模型。用上海产SJ-42型四导生理记录仪测定生理参数左心室收缩压LVSP,左心室内压上升的最大速率(dp/dt)max,冠脉流量CF,心率HR和心电图ECG。结果:离体作功心脏的工作状态受其冠脉压强变化的影响,当灌注压Pc=9kPa时,心脏处于最佳状态。灌注压过高或过低均可导致心脏功能减弱。结论:心脏自身存在冠脉压强感受系统,在冠脉压强发生变化时,心脏自主地调节着工作状态。 展开更多
关键词 离体作功心脏 冠脉压强 冠脉压强感受系统 自主调节
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The Development of A Fluorescence Polarization Immunoassay for Aflatoxin Detection 被引量:11
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作者 SHENG Ya Jie EREMIN Sergei +3 位作者 MI Tie Jun ZHANG Su Xia SHEN Jian Zhong WANG Zhan Hui 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第2期126-129,共4页
A fluorescence polarization immunoassay (FPIA) was developed for the analysis ofaflatoxins (AFs) using an anti-aflatoxin B1 (AFB1) monoclonal antibody and a novel fluorescein-labeled AFB1 tracer. The FPIA showed... A fluorescence polarization immunoassay (FPIA) was developed for the analysis ofaflatoxins (AFs) using an anti-aflatoxin B1 (AFB1) monoclonal antibody and a novel fluorescein-labeled AFB1 tracer. The FPIA showed an IC50 value of 23.33 ng/mL with a limit of detection of 13.12 ng/mL for AFB1. The cross-reactivities of AFB1, AFB2, AFG1, AFG2, AFM1, and AFM2 with the antibody were 100%, 65.7%, 143%, 23.5%, 111.4%, and 2%, respectively. The group-specificity of anti-AFB1mAb indicated that the FPIA could potentially be used in a screening method for the detection of total AFs, albeit not AFG2 and AFM2. The total time required for analyzing 96 samples in one microplate was less than 5 rain. This study demonstrates the potential usefulness of the FPIA as a rapid and simple technique for monitoring AFs. 展开更多
关键词 FPIA AFB The Development of A Fluorescence Polarization Immunoassay for Aflatoxin Detection AFM EDF
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JAK-STAT pathway in carcinogenesis:Is it relevant to cholangiocarcinoma progression? 被引量:14
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作者 Olga V Smirnova Tatiana Yu Ostroukhova Roman L Bogorad 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第48期6478-6491,共14页
The features of JAK-STAT signaling in liver cells are discussed in the current review. The role of this signaling cascade in carcinogenesis is accentuated. The possible involvement of this pathway and alteration of it... The features of JAK-STAT signaling in liver cells are discussed in the current review. The role of this signaling cascade in carcinogenesis is accentuated. The possible involvement of this pathway and alteration of its elements are compared for normal cholangiocytes, cholangiocarcinoma predisposition and development. Prolactin and interleukin-6 are described in detail as the best studied examples. In addition, the non-classical nuclear translocation of cytokine receptors is discussed in terms of its possible implication to cholangiocarcinoma development. 展开更多
关键词 胆管癌 活化剂 催乳激素 治疗方法
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Aberrant expression of alternative isoforms of transcription factors in hepatocellular carcinoma 被引量:3
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作者 Olga Krivtsova Anna Makarova Natalia Lazarevich 《World Journal of Hepatology》 CAS 2018年第10期645-661,共17页
Hepatocellular carcinoma(HCC) is one of the most prevalent malignancies worldwide and the second leading cause of death among all cancer types. Deregulation of the networks of tissue-specific transcription factors(TFs... Hepatocellular carcinoma(HCC) is one of the most prevalent malignancies worldwide and the second leading cause of death among all cancer types. Deregulation of the networks of tissue-specific transcription factors(TFs) observed in HCC leads to profound changes in the hepatic transcriptional program that facilitates tumor progression. In addition, recent reports suggest that substantial aberrations in the production of TF isoforms occur in HCC. In vitro experiments have identified distinct isoform-specific regulatory functions and related biological effects of liver-specific TFs that are implicated in carcinogenesis, which may be relevant for tumor progression and clinical outcome. This study reviews available data on the expression of isoforms of liver-specific and ubiquitous TFs in the liver and HCC and their effects, including HNF4α, C/EBPs, p73 and TCF7 L2, and indicates that assessment of the ratio of isoforms and targeting specific TF variants may be beneficial for the prognosis and treatment of HCC. 展开更多
关键词 ALTERNATIVE ISOFORMS TRANSCRIPTION factors Hepatocellular carcinoma ALTERNATIVE SPLICING Hepatic differentiation PERSONALIZED treatment
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Emission of High Energy during Super-Compressibility of Supersonic Jets 被引量:2
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作者 Kholmurad Khasanov 《Open Journal of Fluid Dynamics》 2012年第4期172-179,共8页
New source of light emission of high energy is found due to arising of instability in supersonic jets. These phenomena are observed in gas jets flowing from the nozzle with a central cone. It leads to high acceleratio... New source of light emission of high energy is found due to arising of instability in supersonic jets. These phenomena are observed in gas jets flowing from the nozzle with a central cone. It leads to high accelerations of the molecules, ions and elementary particles. The emission spectra of the jets are obtained. Decoding of the spectra allowed us to define inverted population of rotational and vibrational levels, electrons temperature, rotational and vibrational temperatures for molecular ions. Internal energy decreasing provides the instability and gas volume decreasing due to internal forces;super-compressibility is result of it;its produce high density of light energy emission in various continuous media. 展开更多
关键词 Internal ENERGY DECREASING Light of High Density of Electromagnetic ENERGY EMISSION Super-Compressibility SUPERSONIC Jets
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ACTIVE INTERMEDIATES IN PHOTORADICAL AGING OF POLYMERS 被引量:1
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作者 M.Ya.Mel’nikov 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2001年第2期167-173,共7页
The data referring to the mechanism and efficiency of electronically excited macroradical and radical anionreactions, the important role of photochemical chain reactions in polymers are presented, It was found that by... The data referring to the mechanism and efficiency of electronically excited macroradical and radical anionreactions, the important role of photochemical chain reactions in polymers are presented, It was found that by varying photonenergy, temperature, photolysis time and competition between thermal and photochemical reactions, it is possible to change the functional composition and molecular weight distribution of polymers. 展开更多
关键词 Macroradicals Radical anions Photochemical reactions AGING
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Effect of poly(3-hydroxyalkanoates) as natural polymers on mesenchymal stem cells 被引量:1
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作者 Vera Voinova Garina Bonartseva Anton Bonartsev 《World Journal of Stem Cells》 SCIE 2019年第10期764-786,共23页
Mesenchymal stem cells(MSCs)are stromal multipotent stem cells that can differentiate into multiple cell types,including fibroblasts,osteoblasts,chondrocytes,adipocytes,and myoblasts,thus allowing them to contribute t... Mesenchymal stem cells(MSCs)are stromal multipotent stem cells that can differentiate into multiple cell types,including fibroblasts,osteoblasts,chondrocytes,adipocytes,and myoblasts,thus allowing them to contribute to the regeneration of various tissues,especially bone tissue.MSCs are now considered one of the most promising cell types in the field of tissue engineering.Traditional petri dish-based culture of MSCs generate heterogeneity,which leads to inconsistent efficacy of MSC applications.Biodegradable and biocompatible polymers,poly(3-hydroxyalkanoates)(PHAs),are actively used for the manufacture of scaffolds that serve as carriers for MSC growth.The growth and differentiation of MSCs grown on PHA scaffolds depend on the physicochemical properties of the polymers,the 3D and surface microstructure of the scaffolds,and the biological activity of PHAs,which was discovered in a series of investigations.The mechanisms of the biological activity of PHAs in relation to MSCs remain insufficiently studied.We suggest that this effect on MSCs could be associated with the natural properties of bacteria-derived PHAs,especially the most widespread representative poly(3-hydroxybutyrate)(PHB).This biopolymer is present in the bacteria of mammalian microbiota,whereas endogenous poly(3-hydroxybutyrate)is found in mammalian tissues.The possible association of PHA effects on MSCs with various biological functions of poly(3-hydroxybutyrate)in bacteria and eukaryotes,including in humans,is discussed in this paper. 展开更多
关键词 MESENCHYMAL stem cells POLYHYDROXYALKANOATES Poly(3-hydroxybutyrate) Tissue engineering Differentiation Natural functions MICROBIOTA Bone INTESTINE
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Analysis of Observed and Modelled Near-Surface Wind Extremes over the Sub-Arctic Northeast Pacific 被引量:1
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作者 Alexander Kislov Vladimir Platonov 《Atmospheric and Climate Sciences》 2019年第1期146-158,共13页
Wind speed extremes in the sub-Arctic realm of the North-East Pacific region were investigated through extreme value analysis of wind speed obtained from wind simulations of the COSMO-CLM (Consortium for Small-scale M... Wind speed extremes in the sub-Arctic realm of the North-East Pacific region were investigated through extreme value analysis of wind speed obtained from wind simulations of the COSMO-CLM (Consortium for Small-scale Modelling, climate version) mesoscale model, as well as using observed data. The analysis showed that the set of wind speed extremes obtained from observations is a mixture of two different subsets each neatly described by the Weibull distribution. Using special metaphoric terminology, they are labelled as “Black Swans” and “Dragons”. The “Dragons” are responsible for strongest extremes. It has been shown that both reanalysis and GCM (general circulation model) data have no “Dragons”. This means that such models underestimate wind speed maxima, and the important circulation process generating the anomalies is not simulated. The COSMO-CLM data have both “Black Swans” and “Dragons”. This evidence provides a clue that an atmospheric model with a detailed spatial resolution (we used in this work the data from domain with 13.2 km spatial resolution) does reproduce the special mechanism responsible for the generation of the largest wind speed extremes. However, a more thorough analysis shows that the differences in the parameters of the cumulative distribution functions are still significant. The ratio between the modelled Dragons and Black Swans can reach up to only 10%. It is much less than 30%, which was the level established for observations. 展开更多
关键词 EXTREME WIND SPEED ANALYSIS Modelled EXTREME WIND SPEED Arctic and SUB-ARCTIC Circulation
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褶皱带橄榄岩-榴辉岩杂岩和稳定地块含金刚石岩筒的成因特征(英文)
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作者 A.A. Marakushev A.V. Bobrov +1 位作者 N.A. Paneyakh V.K. Garanin 《地学前缘》 EI CAS CSCD 北大核心 2007年第2期109-128,共20页
金刚石母岩可以是榴辉岩、辉石岩、橄榄岩等多种岩石,它们与金刚石都是在地幔深处形成的,并上侵最终固结于地壳中。母岩中的金刚石等矿物在地壳中又发生准稳定生长。地壳中金伯利岩和钾镁煌斑岩岩浆作用对金刚石母岩侵入体进行改造,使... 金刚石母岩可以是榴辉岩、辉石岩、橄榄岩等多种岩石,它们与金刚石都是在地幔深处形成的,并上侵最终固结于地壳中。母岩中的金刚石等矿物在地壳中又发生准稳定生长。地壳中金伯利岩和钾镁煌斑岩岩浆作用对金刚石母岩侵入体进行改造,使原生金刚石发生破碎、溶解、再生长等一系列变化,并形成巨晶、劣质金刚石和黑金刚石等新类型,这些现象不是在金刚石母岩形成之初发生的。 展开更多
关键词 褶皱带 稳定地块 金刚石远景 层状侵入体 金伯利岩筒 原生岩浆
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Band Structure and Optical Gain of InGaAs/GaAsBi Type-Ⅱ Quantum Wells Modeled by the k·p Model
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作者 王畅 潘文武 +1 位作者 Konstantin Kolokolov 王庶民 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期133-136,共4页
Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells(QWs) with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-con... Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells(QWs) with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-consistent k·p Hamiltonian, taking into account valence band mixing and the strain effect. Our calculations show that the M-shaped type-Ⅱ QWs are a promising structure for making 1.3 um lasers at room temperature because they can easily be used to obtain 1.3 um for photoluminescence with a proper thickness and have large wave-function overlap for high optical gain. 展开更多
关键词 As BI In Ga Band Structure and Optical Gain of InGaAs/GaAsBi Type Quantum Wells Modeled by the k p Model
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重组具有改良特性的D-氨基酸氧化酶
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作者 S.V Khoronenkova V.I. Tishkov 《生物工程学报》 CAS CSCD 北大核心 2008年第12期2125-2126,共2页
在大肠杆菌细胞中表达三角酵母D-氨基酸氧化酶,并对重组酶的性质进行了研究。制备的单一突变体与野生型酶相比,具有2.4倍的热稳定性或底物特异性变化光谱。结果显示突变的TvDAAO在氧化头孢菌素中催化效果优于野生型酶。并将一个突变的重... 在大肠杆菌细胞中表达三角酵母D-氨基酸氧化酶,并对重组酶的性质进行了研究。制备的单一突变体与野生型酶相比,具有2.4倍的热稳定性或底物特异性变化光谱。结果显示突变的TvDAAO在氧化头孢菌素中催化效果优于野生型酶。并将一个突变的重组TvDAAO制备成结晶,并解析了2.8?分辨率下的晶体结构。 展开更多
关键词 D-氨基酸氧化酶 三角酵母 定向诱变 X射线结构
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Numerical Simulation of Self-Pumped Phase Conjugate Plane-Curve Loop Mirror Based on Photorefractive Nonlinearity
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作者 Mehran Vahdani Moghaddam Zeynab Chenari +2 位作者 Hamid Latifi Vladimir Vladimirovich Shuvalov Konestantin Vaentinovich Rudenko 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第8期2888-2891,共4页
我们在一个自我抽的阶段处理短暂进程的计算机模拟基于 BaTiO3 结合飞机曲线循环镜子。在最佳的情形非线性的 re。ectivity 并且。如此的一面镜子的 delity 分别地完成 0.80 - 0.90 和 0.95 - 0.98。产生结合波浪 -- 前面由于从在自我... 我们在一个自我抽的阶段处理短暂进程的计算机模拟基于 BaTiO3 结合飞机曲线循环镜子。在最佳的情形非线性的 re。ectivity 并且。如此的一面镜子的 delity 分别地完成 0.80 - 0.90 和 0.95 - 0.98。产生结合波浪 -- 前面由于从在自我的区域被生产的动态全息图散布发生 -- 前面、向后的横梁的交叉。在如此的一个模型,过去到不稳定的产生政体的情形类似于自我 -- 抽的阶段结合飞机 - 飞机环镜子并且实质地 di。从一个单身者的 ers -- 水晶两倍阶段结合镜子。 展开更多
关键词 数字模拟 平面反光镜 非线性数学 光学应用
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Observation of nonlinear disclination states 被引量:1
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作者 Boquan Ren Antonina A.Arkhipova +10 位作者 Yiqi Zhang Yaroslav V.Kartashov Hongguang Wang Sergei A.Zhuravitskii Nikolay N.Skryabin Ivan V.Dyakonov Alexander A.Kalinkin Sergei P.Kulik Victor O.Kompanets Sergey V.Chekalin Victor N.Zadkov 《Light(Science & Applications)》 SCIE EI CSCD 2023年第9期1818-1829,共12页
Introduction of controllable deformations into periodic materials that lead to disclinations in their structure opens novel routes for construction of higher-order topological insulators hosting topological states at ... Introduction of controllable deformations into periodic materials that lead to disclinations in their structure opens novel routes for construction of higher-order topological insulators hosting topological states at disclinations.Appearance of these topological states is consistent with the bulk-disclination correspondence principle,and is due to the filling anomaly that results in fractional charges to the boundary unit cells.So far,topological disclination states were observed only in the linear regime,while the interplay between nonlinearity and topology in the systems with disclinations has been never studied experimentally.We report here on the experimental observation of the nonlinear photonic disclination states in waveguide arrays with pentagonal or heptagonal disclination cores inscribed in transparent optical medium using the fs-laser writing technique.The transition between nontopological and topological phases in such structures is controlled by the Kekulédistortion coefficient r with topological phase hosting simultaneously disclination states at the inner disclination core and spatially separated from them corner-I,corner-II,and extended edge states at the outer edge of the structure.We show that the robust nonlinear disclination states bifurcate from their linear counterparts and that location of their propagation constants in the gap and,hence,their spatial localization can be controlled by their power.Nonlinear disclination states can be efficiently excited by Gaussian input beams,but only if they are focused into the waveguides belonging to the disclination core,where such topological states reside.Our results open new prospects for investigation of nonlinear effects in topological systems with disclinations and are relevant for different areas of science,including Bose-Einstein and polariton condensates,where potentials with the disclinations can be created. 展开更多
关键词 STRUCTURE TOPOLOGICAL NONLINEAR
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