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The synergetic effects of two CCAAT boxes in Aspergillus niger glaA gene promoter on activation of PglaA transcription

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Science China(Life Sciences) 2004年第2期47卷 139-147页

作者： WANG h. m. Genencor International Inc. 925 Page Mill Road Palo Alto California 94304 USA

EmSA and footprinting analyses have revealed that the -489—-414 bp and the -390—-345 bp (designated DC and PC respectively) upstream of the Aspergillus niger T21 glaA gene were bound by one protein factor in the A. niger T21 whole cell extract. Both DC and PC contained CCAAT pentanucleotides. The functions of DC and PC in regulation of expression of glucoamylase (GLA) were studied. CCAAT pentanucleotides were replaced with CGTAA and the mutated DNA fragments DCm and PCm lost the binding activities of protein factors in vitro. In vivo when either DC or PC was mutated or the relative orientations between them were changed on the PglaA, the transcriptional activity of PglaA decreased to a basal level. Introduction of multi-copies of DC into the original site at the PglaA in A. niger T21 decreased the expression of endogenous GLA expression and the exogenous reporter E. coli uidA gene introduced under the PglaA promoter, while having no effect on the uidA gene under the control of PgpdA. EmSA re-vealed that the levels of the specific DNA-binding protein factors in the transformants maintained the same meaning that introduction of multi-copies of DC caused the titration effect. AnghapC gene was cloned from A. niger T21 cDNA and introduced into the DC multi-copied strains. The expression of AnghapC improved the expression of the endogenous GLA and the exogenous gene controlled by PglaA. These results showed that both the CCAAT pentanucleotides were necessary for DC and PC binding to the protein factors, and the simultaneous binding of DC and PC to the protein was necessary for promoting the transcriptional activity of PglaA. AnghapC was the specific positive trans-acting protein factor binding to DC.

关键词： Aspergillus niger glucoamylase, synergetic effect, mutation analysis, multi-copy of CCAAT box, titration effect.

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植物系统发生海报——以演化视角介绍植物多样性的科教资料项目

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生物多样性 2025年

作者：蒋陈焜郁文彬饶广远黎怀成 Julien B.Bachelier hartmut h.hilger Theodor C.h.Cole 北京大学生命科学学院蛋白质与植物基因研究国家重点实验室北京大学前沿交叉学科研究院北京大学-清华大学生命科学联合中心中国科学院西双版纳热带植物园综合保护中心/云南省热带雨林与亚洲象保护重点实验室 Dahlem Centre of Plant Sciences (DCPS)， Institute of Biology， Structural and Functional Plant Diversity， Freie Universit?t Berlin

中国的植物多样性保护行动虽然提升了公众对多样性的认识，但这些努力往往未能深入到理解植物多样性演化及其保护的深层意义。从演化的视角进行植物多样性宣传教育，有利于促进对多样性的综合理解，增进对多样性保护的认可。然而， ... 详细信息

中国的植物多样性保护行动虽然提升了公众对多样性的认识，但这些努力往往未能深入到理解植物多样性演化及其保护的深层意义。从演化的视角进行植物多样性宣传教育，有利于促进对多样性的综合理解，增进对多样性保护的认可。然而，现有资料多集中于物种的识别、鉴定与分类，缺乏从生物演化角度对植物多样性进行系统性介绍的内容。本文介绍了一个具有全球影响力的科教资料案例——由美裔德国植物学家Theodor C. h. Cole发起的植物系统发生海报(Plant Phylogeny Posters)项目。该项目通过整合最新的系统与演化植物学研究成果，以系统发生为线索介绍植物多样性及其亲缘关系，旨在利用系统发生树所蕴含的丰富演化思想内涵，启发读者理解植物多样性与演化。海报以系统发生树结合植物类群的形态、地理分布、物种数量等数据信息，直观展示了多个分类等级的重要类群的演化历史。在数十所大学和科研机构的45位研究人员的努力下， 70张系统发生海报已被翻译成中文，并向所有人免费开放获取。这一科教项目有望为增进公众深入理解植物多样性及其保护行动提供宝贵的资源和帮助。

关键词：植物多样性演化系统发生科教资料

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Dirac R-matrix calculations of photoionization cross sections of Ni Ⅻ and atomic structure data of Ni 

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Chinese Physics B 2017年第2期26卷 127-140页

作者： R T Nazirt m A Bari m Bilal S Sardar m h Nasim m Salahuddin Department of Physics and Applied mathematics Pakistan Institute of Engineering and Applied Sciences Islamabad 45650 Pakista

We performed R-matrix calculations for photoionization cross sections of the two ground state configuration 3s^23p^5（~2P_（3/2,1/2）~o） levels and 12 excited states of Ni Ⅻ using relativistic Dirac Atomic R-matrix Codes（DARC） across the photon energy range between the ionizations thresholds of the corresponding states and well above the thresholds of the last level of the Ni XIII target ion. Generally, a good agreement is obtained between our results and the earlier theoretical photoionization cross sections. moreover, we have used two independent fully relativistic GRASP and FAC codes to calculate fine-structure energy levels, wavelengths, oscillator strengths, transitions rates among the lowest 48 levels belonging to the configuration（3s^23p^4, 3s3p^5, 3p^6, 3s^23p^33d） in Ni XIII. Additionally, radiative lifetimes of all the excited states of Ni XIII are presented. Our results of the atomic structure of Ni XIII show good agreement with other theoretical and experimental results available in the literature. A good agreement is found between our calculated lifetimes and the experimental *** present results are useful for plasma diagnostic of fusion and astrophysical plasmas.

关键词： photoionization cross sections energy levels wavelengths lifetimes

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Surface hardness,thermal,optical,and photon attenuation coefficients assessment for dysprosium-doped tellurite glasses

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Journal of Rare Earths 2023年第7期41卷 1083-1090,I0004页

作者： hesham m.h.Zakaly D.E.Abulyazied h.A.Saudi B.m.Alotaibi Shams A.m.Issa Institute of Physics and Technology Ural Federal UniversityYekaterinburg620002Russia Faculty of Science Al-Azhar UniversityAssuit BranchAssuit71524Egypt Polymer Lab Department of PetrochemicalsEgyptian Petroleum Research InstituteNasr CityCairoEgypt Department of Physics Faculty of ScienceUniversity of TabukTabukSaudi Arabia Physics Department Faculty of ScienceAl-Azhar University(Girls Branch)Nasr CityCairoEgypt Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

Using a melt-cooling process with the host glass,Dy_(2)O_(3)(1 wt%,2 wt%,3 wt%,and 4 wt%) doped tellurite glasses were produced.A(65-x)TeO_(2)-20B_(2)O_(3)-10Al_(2)O_(3)-SGeO_(2)-xDy_(2)O_(3) glass system was analyzed by Xray *** patterns have a hump at 2θ=27°-29° and no sharp peaks,indicating that all the glass samples are *** Vickers microhardness determines how resistant a glass is to persistent deformation produced by a harder *** scanning calorimetry(DSC) at 300-550℃ was used to evaluate the thermal properties of the Dy_x glass *** glass transition temperature T_g(small endothermic peak),start crystallization temperature T_x and crystallization temperature T_c can all be seen on the DSC thermogram(exothermic peaks).The UV-Vis transmittance and absorption spectra were *** optical data show that the values of E_d^(ir),E_g^(Ind) and E_U decrease as the amount of Dy_(2)O_(3)increases,indicating a narrowing of the tails due to localized states in the forbidden gap.A concentration quenching event occurs when Dy^(3+) concentrations are above a certain threshold(1%).The addition of Dy_(2)O_(3) increases glass density,while the addition of other Dy(Ⅲ) oxides increases sample *** radiation shielding values change as a consequence of density *** sample with the highest amount of Dy_(2)O_(3)(Dy_(4)) has stronger radiation shielding characteristics;hence,it is superior in terms of shielding outcomes at all energy *** Dy_x samples can be used in various forms of ionizing radiation shielding.

关键词： melt-cooling process DSC Dysprosium(Ⅲ)oxides Surface hardness Photon attenuation Rare earths

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Parameters for Cold Collisions of Lithium and Caesium Atoms

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Chinese Physics Letters 2011年第6期28卷 56-58页

作者： Jamieson m.J Ouerdane h School of Computing Science University of GlasgowGlasgow G128QQUK mediterranean Institute of Fundamental Physics Via Appia Nuova 3100040 MarinoRomeItaly CNRT matériaux UmS CNRS 3318 6 Boulevard Maréchal Juin14050 Caen CedexFrance

We calculate the s-wave scattering length and effective range and the p-wave scattering volume for 7Li atoms interacting with 133Cs atoms via the X1Σ+molecular *** length and volume are found by fitting the log-derivative of the zero energy wave function evaluated at short range to a long range expression that accounts for the leading van der Waals dispersion potential and then incorporating the remaining long range dispersion contributions to first *** effective range is evaluated from a quadrature *** calculated parameters are checked from the zero energy limits of the scattering phase *** comment on ill-conditioning in the calculated s-wave scattering length.

关键词： potential dispersion checked

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Expulsion characterization in resistance spot welding by means of a hardness mapping technique

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International Journal of minerals,metallurgy and materials 2014年第9期21卷 894-897页

作者： h.Ghazanfari m.Naderi Department of mining and metallurgy AmirKabir University of Technology424 Hafez AveTehran 15875-4413 Iran

Expulsion is an undesired event during resistance spot welding because the weld quality deteriorates. It is the ejection of molten metal from the weld nugget which usually occurs due to applying a high current for a short welding time. Expulsion has a significant impact on the final yield strength of the weld, thus the detection and characterization of expulsion events is significant for the quality assurance of resistance spot welds. In this study, hardness mapping, using a scanning hardness machine, was used as a quality assurance technique for re- sistance spot welding. hardness tests were conducted on a resistance spot welded sample to prepare a hardness map. The test results showed good correlation between the hardness map and metallographic cross sections. The technique also provided further fundamental understand- ing of the resistance spot welding process, especially regarding the occurrence of expulsion in the nugget.

关键词： alloy steel spot welding heat-affected zone hardness mapping

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Structural,magnetic and electrical characterization of the La_(0.7)Ca_(0.3)Co_(1–x)mn_xO_3(x=0,0.7 and 1) compounds prepared by a simple method

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Journal of Rare Earths 2014年第10期32卷 965-972页

作者： m.Eshraghi P.Kameli F.Khalili m.h.Ehsani h.Salamati Department of Physics Payame Noor University Department of Physics Isfahan University of Technology Department of Physics Semnan University

Structural, magnetic and electrical properties of the La0.7Ca0.3Co1–xmnxO3（x=0, 0.7 and 1） samples prepared by a simple method were systematically studied and it was found that the crystal structure was transformed from rhombohedral for La0.7Ca0.3CoO3（LCCO） and La0.7Ca0.3Co0.3mn0.7O3（LCCmO） samples to orthorhombic for La0.7Ca0.3mnO3（LCmO） sample. The AC magnetic susceptibility measurements showed that LCCO sample underwent a transition from paramagnetic（Pm） to ferromagnetic（Fm） phase at Curie temperature, TC^155 K and below Curie temperature, the glassy ferromagnetism nature was observed. In LCCmO sample,clear evidence of spin glass（SG） state was observed at low temperature. Pm-Fm phase transition at about TC^260 K and long range Fm order at low temperatures were observed in LCmO sample. Both the LCCO and LCCmO samples exhibited insulating behavior in the whole range of measuring temperature whereas the LCmO sample underwent a clear metal-insulator（mI） transition at about TmI^263 K, corresponding to Curie temperature. metallic region of ρ（T） curve of the LCmO sample was fitted to the model of electron-electron and electron-magnon scattering. The charge carrier transport behavior in all the samples was compared based on polaronic models.

关键词： cobaltite spin glass manganites rare earths

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Experimental Study of Wave Attenuation in Trapezoidal Floating Breakwaters

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China Ocean Engineering 2019年第1期33卷 103-113页

作者： A.h.Nikpour m.N.moghim m.A.Badri Department of Civil Engineering Isfahan University of Technology Research Institute for Subsea Science and Technology Isfahan University of Technology

A comprehensive experimental study was carried out on the regular wave attenuation with a trapezoidal pontoontype floating breakwater(FB) in deep water. The functionalities of two simple FB geometries consist of a rectangle and a trapezoid with the slope of 60° were investigated under the wave attack. A two-dimensional wave flume was used in the experiment; the incident, transmitted waves, mooring line forces and motion responses of the floating breakwaters were measured. Also the influence of the sea state conditions(incident wave height and wave period)and structural parameters(draught of the structure) were investigated using the trapezoidal FB. Our experimental results indicated that the trapezoidal FB significantly reduced the wave transmission and mooring line force when compared with rectangular FBs. A new formula was developed in order to predict the value of the transmission coefficient in trapezoidal FBs with the slope of 60°. Experimental data showed to be consistent with the results of the formula.

关键词： regular waves floating breakwater(FB) wave flume trapezoid mooring line force transmission

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mechanism of fracture in macro- and micro-scales in hollow centre cracked disc specimen

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Journal of Central South University 2015年第11期22卷 4426-4433页

作者： m.Eftekhari A.Baghbanan h.hashemolhosseini h.Amrollahi Department of mining Engineering Isfahan University of Technology (IUT)

The hollow centre cracked disc(hCCD) specimen is one of the suggested alternative methods for determining the fracture toughness of rock. This work aims to investigate the fracture mechanism in hCCD in macro- and micro-scales using numerical methods, extended finite element method(X-FEm) and particle flow code(PFC) modeling, respectively. In the X-FEm, heaviside and near-tip enrichment functions are employed to consider the presence of the crack in the model. In PFC modeling the movement and interaction of stressed assemblies of rigid spherical particles are modeled using the distinct element method(DEm). A numerical code called mEX-FEm based on XFEm has been developed to simulate the problems involving crack. The models of pure modes I and Ⅱ in macro-scale are simulated in micro-scale. The results show that dimensionless stress intensity factors(YI, YⅡ) for pure modes I and Ⅱ increase by increasing the crack length ratio. The angle at which the pure mode Ⅱ occurs decreases by increasing the crack length ratio. In mixed mode I-Ⅱ, The value of YI decreases by increasing the crack angle, while the value of YⅡ increases to a given crack angle and then it decreases. moreover, the fracture in micro-scale, unlike the macro-scale, includes a combination of different modes of fracturing.

关键词： hollow centre cracked disc(hCCD) extended finite e

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Numerical Analysis of mhD Accelerator with Non-Equilibrium Air Plasma

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Plasma Science and Technology 2012年第12期14卷 1110-1115页

作者： m.ANWARI h.h.QAZI SUKARSAN N.hARADA Electrical Engineering Department Umm Al-Qura University Faculty of Electrical Engineering Universiti Teknologi Malaysia Faculty of Electrical Engineering Universitas Islam "45" Bekasi Department of Electrical Engineering Nagaoka University of Technology

magnetohydrodynamic （mhD） accelerator is proposed as a next generation propulsion system. It can be used to increase the performance of a propulsion system. The objective of this study is to investigate the performance of mhD accelerator using non-equilibrium air plasma as working gas. In this study, the fundamental performance of mhD accelerator such as flow performance and electrical performance is evaluated at different levels of applied magnetic field using I-D numerical simulation. The numerical simulation is developed based on a set of differential equations with mhD approximation. To solve this set of differential equations the macCormack scheme is used. A specified channel designed and developed at NASA marshall Space Flight Centre is used in the numerical simulation. The composition of the simulated air plasma consists of seven species, namely, N2, N, O2, O, NO, NO＋, and e-. The performance of the non-equilibrium mhD accelerator is also compared with the equilibrium mhD accelerator.

关键词： mhD accelerator Faraday type connection non-equilibrium air plasma

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