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Materials Sciences and Applications 2014年第14期5卷 1074-1078页

作者： Thomas jansen Thomas jüstel Department of Chemical Engineering Münster University of Applied Sciences Steinfurt Germany

Yttrium aluminum garnet (YAG) and Lutetium aluminum garnet (LuAG) doped with Ce3+ are widely applied phosphor powders or ceramics for the conversion of blue into green to yellow light in the rapidly expanding market of white light emitting high power LEDs. Surprisingly, the temperature dependent reflection and excitation spectra of these well-established materials have not been investigated until today. In this work, we report the temperature dependence of the reflection and excitation spectra of Ce3+ doped YAG and LuAG in the temperature range from 300 to 800 K.

关键词： Temperature-Dependent Reflection Excitation Spectra Garnet Phosphor Ceramics Thermal Population

Mentors Expressing What They Value Through Their Writings: Emphasizing the Person in Mathematics

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ECNU Review of Education 2021年第2期4卷 230-240页

作者： Wee Tiong Seah Qiaoping Zhang Alan j.Bishop The University of Melbourne The Education University of Hong Kong Monash University

Purpose:This article identifies an issue in mathematics education,that is,the perceived lack of emphasis in recent times of the roles that the"person"plays in the development of *** purpose is to exami ne how values/valui ng might con tribute to addressi ng the ***/Approach/Methods:“Data”were collected from several purposeful conversations among the three *** conversations were audio-recorded and *** transcript was then subjected to content analysis to identify ***:The data analysis yielded two novel approaches to raising learners'awareness of the humanness of *** would be to reframe the values that are operationalized when mathematics is taught and learnt,as processes of valuing which teachers and students engage in,*** sec ond approach would be to ack no wledge that writers of mathematics/mathematicia ns are not simply prese nting kn owledge but are also acti ng as men tors conv eying and transmitting messages about the ***/Value:The invoIvement of the"person" in the development of mathematics is not new knowledge,though it can be made more visible in mathematics *** article identifies two approaches-valuing and mentoring-which are novel in that they are already part of the pedagogical process and thus,accessible.

关键词： Mathematics mentoring values valuing

Divergent male and female mate preferences do not explain incipient speciation between lizard lineages

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Current Zoology 2020年第5期66卷 485-492页

作者： Claire A.McLean Richard A.Bartle Caroline M.Dong Katrina j.Rankin Devi Stuart-Fox School of BioSciences The University of MelbourneParkville VIC 3010Australia Sciences Department Museums VictoriaCarlton VIC 3053Australia

Diversification in sexual signals is often taken as evidenee for the importance of sexual selection in speciatio ***,in order for sexual selection to gen erate reproductive isolati on between populations,both signals and mate preferences must diverge ***,assortative mating may result from multiple behavioral mecha nisms,in eluding female mate pref ere nces,male mate preferences,and male-male competition;yet their relative contributions are rarely ***,we explored the role of mate pref ere nces and male competitive ability as pote ntial barriers to gene flow between 2 diverge nt lineages of the taw ny dragon lizard,Ctenophorus decresii,which differ in male throat *** found stronger behavioral barriers to pairings between southern lineage males and northern lineage females than between northern males and southern females,indicating incomplete and asymmetric behavioral isolating *** results were driven by both male and female mate preferences rather than lineage differences in male competitive *** trasexual selecti on is therefore un likely to drive the outcome of sec on dary contact in ***,despite its widely ack no wledged importa nee in *** results are consiste nt with the emergi ng view that although both male and female mate pref ere nces can diverge alongside sexual signals,speciation is rarely driven by divergent sexual selection alone.

关键词： Ctenophorus decresii hybridization male-male competition secondary contact sexual selection

HOXB9 acetylation at 27 is responsible for its suppression of colon cancer progression

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HOXB9 acetylation at 27 is responsible for its suppression o...

The amrG1 gene is involved in the activation of acetate in Corynebacterium glutamicum

中国解剖学会2019年年会

作者： Song j Wang T Xu W Wang P Wan j Wang Y Zhan j Zhang H Key Laboratory of Carcinogenesis and Translational Research （Ministry of Education） and State Key Laboratory of Natural and Biomimetic DrugsPekingUniversity Health Science Centre

＜正＞We previously reported that HOXB9 is overexpressed in colon cancer and predicts a favourable patient outcome, which is opposite to the tumour-promoting role of HOXB9in other *** hypothesized that HOXB9 acetylation may account for its inhibitory role in colon *** aim to examine the role of acetylated HOXB9 in colon cancer cells and *** ack27-HOXB9 levels in

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Science China(Life Sciences) 2005年第2期48卷 97-105页

作者： R.Gerstmeir S.Schnicke B.j.Eikmanns Deptartment of Microbiology & Biotechnology Ulm University D-89069 Ulm GermanyDeptartment of Microbiology & Biotechnology Ulm University D-89069 Ulm GermanyDeptartment of Microbiology & Biotechnology Ulm University D-89069 Ulm Germany

During growth of Corynebacterium glutamicum on acetate as its carbon and energy source, the expression of the pta-ack operon is induced, coding for the acetate-activating en- zymes, which are phosphotransacetylase (PTA) and acetate kinase (AK). By transposon rescue, we identified the two genes amrG1 and amrG2 found in the deregulated transposon mutant C. glutamicum G25. The amrG1 gene (NCBI-accession: AF532964) has a size of 732 bp, encoding a polypeptide of 243 amino acids and apparently is partially responsible for the regulation of acetate metabolism in C. glutamicum. We constructed an in-frame deletion mutant and an over- expressing strain of amrG1 in the C. glutamicum ATCC13032 wildtype. The strains were then analyzed with respect to their enzyme activities of PTA and AK during growth on glucose, acetate and glucose or acetate alone as carbon sources. Compared to the parental strain, the amrG1 deletion mutant showed higher specific AK and PTA activities during growth on glucose but showed the same high specific activities of AK and PTA on medium containing acetate plus glu- cose and on medium containing acetate. In contrast to the gene deletion, overexpression of the amrG1 gene in C. glutamicum 13032 had the adverse regulatory effect. These results indicate that the amrG1 gene encodes a repressor or co-repressor of the pta-ack operon.

关键词： amrG1, Corynebacterium glutamicum, acetate activation, phosphotransacetylase, acetate kinase.

amrG1基因在谷氨酸棒杆菌乙酸活化中的作用

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中国科学（C辑） 2004年第3期34卷 223-231页

作者：阮红 R.Gerstmeir S. Schinke B.j. Eikmanns 浙江大学生命科学学院 Department of Microbiology and Biotechnology Ulm University D-89069 Ulm Germany

谷氨酸棒杆菌Corynebacteriumglutamicum可以利用乙酸为碳源和能源进行生长.乙酸代谢中涉及乙酸活化的两个酶为磷酸转乙酰酶PTA和乙酸激酶AK,它们是由pta-ack操纵子经诱导表达产生的.采用转座子挽救法,我们从调控突变株***25中获得了am... 详细信息

谷氨酸棒杆菌Corynebacteriumglutamicum可以利用乙酸为碳源和能源进行生长.乙酸代谢中涉及乙酸活化的两个酶为磷酸转乙酰酶PTA和乙酸激酶AK,它们是由pta-ack操纵子经诱导表达产生的.采用转座子挽救法,我们从调控突变株***25中获得了amrG1和amrG2两个目标基因.经分析鉴定,amrG1基因(NCBIGenBank接受号为AF532964)可能参与乙酸代谢调控,编码作用于pta-ack操纵子的一个调控因子.该调控因子基因序列全长732bp,开放阅读框含有243个氨基酸,分子量约为27kD.通过基因定点缺失和过量表达技术,在谷氨酸棒杆菌野生型菌株中分别构建了amrG1基因缺失菌株和表达菌株,并研究了它们在含有葡萄糖和/或乙酸不同碳源的基本培养基上生长时产生的PTA和AK酶活性特征.酶活性测定结果发现其中的amrG1基因缺失菌株和表达菌株存在着与野生型菌株不同的一系列酶学特征,分析显示:以野生型菌株为对照,amrG1基因缺失菌株在含有葡萄糖碳源的培养基上生长时表现出较高的PTA和AK酶活性,并且在葡萄糖和乙酸两种碳源上生长时表现出与乙酸碳源上生长时几乎同样的PTA和AK酶活性;amrG1基因过量表达对葡萄糖碳源上生长产生的PTA和AK酶活性有一定程度的抑制,即表现出与基因缺失情况相反的调控效应.根据以上结果分析。

关键词： amrGl基因谷氨酸棒杆菌乙酸活化磷酸转乙酰酶乙酸激酶氨基酸工业

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恩施渔塘坝富硒碳质岩中硒的赋存状态

地球化学 2004年第6期33卷 634-640页

作者：朱建明李社红左维 I.Sykorova 苏宏灿郑宝山 j.Pesek 中国科学院地球化学研究所环境地球化学国家重点实验室 Institute of Rock Structure and Mechanics ASCR VHoleovi.kách41 18209 Prague 8Czech Republic 湖北省恩施州卫生防疫站 Faculty of Science Charles University of Prague Albertov 6 Praha 212843 Czech Republic

在渔塘坝富硒碳质岩中发现了自然硒及其系列硒矿物的组合。这些硒矿物有自然硒、方硒铜矿、硒铜蓝、水硒铁石、硒银矿、含硒黄铁矿、含硒黄铜矿和难以确定名称的Fe-Se矿物。其中自然硒、方硒铜矿和硒铜蓝的矿物组合主要分布在断层面附... 详细信息

在渔塘坝富硒碳质岩中发现了自然硒及其系列硒矿物的组合。这些硒矿物有自然硒、方硒铜矿、硒铜蓝、水硒铁石、硒银矿、含硒黄铁矿、含硒黄铜矿和难以确定名称的Fe-Se矿物。其中自然硒、方硒铜矿和硒铜蓝的矿物组合主要分布在断层面附近的碳质硅质岩中,自然硒与方硒铜矿的矿物组合主要分布在高碳质泥岩中,水硒铁石及未确定的Fe-Se矿物主要赋存于露头处的富硒碳质岩中。硒矿物中除自然硒较普遍地存在外,其他矿物并不是均匀地分布于富硒碳质岩中,而是局部性地出现。Cu-Se矿物的大量发育表明铜可能在硒的表生迁移转化中起着某种重要的作用。

关键词：富硒碳质岩硒矿物赋存状态渔塘坝

Localization-limited exciton oscillator strength in colloidal CdSe nanoplatelets revealed by the optically induced stark effect

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Light(Science & Applications) 2021年第6期10卷 1122-1132页

作者： Pieter Geiregat Carmelita Roda Ivo Tanghe Shalini Singh Alessio Di Giacomo Delphine Lebrun Gianluca Grimaldi jorick Maes Dries Van Thourhout Iwan Moreels Arjan j.Houtepen Zeger Hens Physics and Chemistry of Nanostructures Department of ChemistryGhent UniversityGentBelgium. Center for Nano and Biophotonics Ghent UniversityGentBelgium. Photonics Research Group Ghent UniversityGentBelgium. Department of Chemical Sciences and Bernal Institute University of LimerickLimerickIreland. Center for Nanophotonics NWO-lnstitute AMOLFScience Park 1041098 XG AmsterdamThe Netherlands. Opto-Electronic Materials Section Department of Chemical EngineeringDelft UniversityDelftThe Netherlands

2D materials are considered for applications that require strong light-matter interaction because of the apparently giant oscillator strength of the exciton transitions in the absorbance ***,the effective oscillator strengths of these transitions have bee n scarcely reported,nor is there a con sistent interpretati on of the obtained ***,we analyse the transition dipole moment and the ensuing oscillator strength of the exciton transition in 2D CdSe nanoplatelets by means of the optically induced Stark effect(OSE).Intriguingly,we find that the exciton absorption line reacts to a high intensity optical field as a transition with an oscillator strength FStark that is 50 times smaller than expected based on the linear absorption *** propose that the pronounced exciton absorption line should be seen as the sum of multiple,low oscillator strength transitions,rather than a single high oscillator strength one,a feat we assign to strong exciton center-of-mass *** the quantum mechanical description of excitons,this 50-fold difference between both oscillator strengths corresponds to the ratio between the cohere nee area of the exciton's center of mass and the total area,which yields a coherence area of a mere 6.1 *** we find that the coherence area in creases with reducing temperature,we conclude that thermal effects,related to lattice vibrations,contribute to exciton *** further support of this localization model,we show that FStark is in dependent of the n anoplatelet area,correctly predicts the radiative lifetime,and lines up for strongly confined quantum dot systems.

关键词： coefficient. spectrum. oscillator

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丛集性头痛与发作性偏头痛的鉴别诊断

世界核心医学期刊文摘（神经病学分册） 2005年第8期1卷 18-19页

作者： Zidverc-Trajkovic j. Pavlovic A.M. Mijajlovic M. 郭俊 Institute of Neurology Dr Subotica 611000 Belgrade Serbia and Montenegro

The utility of the differences between cluster headache (CH) and paroxysmal he micrania (PH) is limited by the considerable overlap of their clinical character istics. We compared 54 patients with CH and eight patients with PH in terms of d emographic features, characteristics of headache attacks, associated autonomic f eatures, temporal forms of disorders, and response to verapamil. According to ou r results, clinical features that distinguished CH and PH patients were: maximal pain localization, ocular in CH patients and extra-ocular in PH group;mean att ack duration was longer and mean attack frequency was lower in CH patients in co mparison with PH patients. Conjuctival injection was the only autonomic sign see n more frequently in CH patients. There were more CH patients with episodic and more PH patients with unremitting form of the disorder in examined groups. Altho ugh statistical analysis pointed out a significant difference between these clin ical features, there was no clinical characteristic that exclusively belonged to one of these headache entities. Demographic characteristics (age,gender, social background), the other headache attack features(nocturnal attacks, interattack tenderness), the other autonomic signs, as well as the response to verapamil did not differ significantly between two groups.

关键词：丛集性头痛鉴别诊断头痛发作神经体征发作持续时间自主神经症状发作间期维拉帕米时间形态发病形式

Multifunctional metasurfaces enabled by simultaneous and independent control of phase and amplitude for orthogonal polarization states

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Light(Science & Applications) 2021年第6期10卷 1088-1098页

作者： Mingze Liu Wenqi Zhu Pengcheng Huo Lei Feng Maowen Song Cheng Zhang Lu Chen Henri jLezec Yanqing Lu Amit Agrawal Ting Xu National Laboratory of Solid-State Microstructures Jiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied SciencesNanjing University210093 NanjingChina Collaborative Innovation Center of Advanced Microstructures 210093 NanjingChina Physical Measurement Laboratory National Institute of Standards and TechnologyGaithersburgMD 20877USA Maryland NanoCenter University of MarylandCollege ParkMD 20877USA School of Optical and Electronic Information and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology430074 WuhanChina

Monochromatic light can be characterized by its three fun dame ntal properties:amplitude,phase,and *** this work,we propose a versatile,transmission-mode all-dielectric metasurface platform that can independently manipulate the phase and amplitude for two orthogonal states of polarization in the visible frequency *** proof-o仁concept experimental demonstration,various single-layer metasurfaces composed of subwavelength-spaced titanium-dioxide nanopillars are designed,fabricated,and characterized to exhibit the ability of polarization-switchable multidimensional light-field manipulation,including polarization-switchable grayscale nanoprinting,nonuniform cylindrical lensing,and complex-amplitude *** envision the metasurface platform dem on strated here to open new possibilities toward creating compact multifunctional optical devices for applications in polarization optics,information encoding,optical data storage,and security.

关键词： phase proof simultaneous