77 resultados para ROTARY INVERTED PENDULUM


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Estrogenic activities of samples from two Chinese lakes, Ya-Er Lake and Donghu Lake, were measured by in vitro recombinant yeast assay and found in both lakes polluted with industrial and domestic wastewater. In methanol extracts of lake water samples the estrogen-like activity was higher than in toluene extracts. These results have been inverted for solid samples. Furthermore, the EC50 value of the water samples was close to the original concentration in the lake.

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The Sleeping Beauty (SB) transposon system, derived from teleost fish sequences, is extremely effective at delivering DNA to vertebrate genomes, including those of humans. We have examined several parameters of the SB system to improve it as a potential, nonviral vector for gene therapy. Our investigation centered on three features: the carrying capacity of the transposon for efficient integration into chromosomes of HeLa cells, the effects of overexpression of the SB transposase gene on transposition rates, and improvements in the activity of SB transposase to increase insertion rates of transgenes into cellular chromosomes. We found that SB transposons of about 6 kb retained 50% of the maximal efficiency of transposition, which is sufficient to deliver 70-80% of identified human cDNAs with appropriate transcriptional regulatory sequences. Overexpression inhibition studies revealed that there are optimal ratios of SB transposase to transposon for maximal rates of transposition, suggesting that conditions of delivery of the two-part transposon system are important for the best gene-transfer efficiencies. We further refined the SB transposase to incorporate several amino acid substitutions, the result of which led to an improved transposase called SB11. With SB11 we are able to achieve transposition rates that are about 100-fold above those achieved with plasmids that insert into chromosomes by random recombination. With the recently described improvements to the transposon itself, the SB system appears to be a potential gene-transfer tool for human gene therapy.

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We demonstrate that a p-n junction created electrically in HgTe quantum wells with inverted band structure exhibits interesting intraband and interband tunneling processes. We find a perfect intraband transmission for electrons injected perpendicularly to the interface of the p-n junction. The opacity and transparency of electrons through the p-n junction can be tuned by changing the incidence angle, the Fermi energy and the strength of the Rashba spin-orbit interaction (RSOI). The occurrence of a conductance plateau due to the formation of topological edge states in a quasi-one-dimensional (Q1D) p-n junction can be switched on and off by tuning the gate voltage. The spin orientation can be substantially rotated when the samples exhibit a moderately strong RSOI.

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The spin Hall effect can be induced by both extrinsic impurity scattering and intrinsic spin-orbit coupling in the electronic structure. The HgTe/CdTe quantum well has a quantum phase transition where the electronic structure changes from normal to inverted. We show that the intrinsic spin Hall effect of the conduction band vanishes on the normal side, while it is finite on the inverted side. By tuning the Cd content, the well width, or the bias electric field across the quantum well, the intrinsic spin Hall effect can be switched on or off and tuned into resonance under experimentally accessible conditions.

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Thick GaN films were grown on sapphire in a home-made vertical HVPE reactor. Effect of nucleation treatments on the properties of GaN films was investigated, including the nitridation of sapphire, low temperature GaN buffer and MOCVD-template. Various material characterization techniques, including AFM, SEM, XRD, CL and PL have been used to assess these GaN epitaxial films. It was found that the surface of sapphire after high temperature nitridation was flat and showed high density nucleation centers. In addition, smooth Ga-polarity surface of epitaxial layer can be obtained on the nitridation sapphire placed in air for several days due to polarity inversion. This may be caused by the atoms re-arrangement because of oxidation. The roughness of N-polarity film was caused by the huge inverted taper domains, which can penetrate up to the surface. The low temperature GaN buffer gown at 650 degrees C is favorable for subsequent epitaxial film, which had narrow FWHM of 307 arcsec. The epitaxial growth on MOCVD-template directly came into quasi-2D growth mode due to enough nucleation centers, and high quality GaN films were acquired with the values of the FWHM of 141 arcsec for (002) reflections. After etching in boiled KOH, that the total etch-pit density was only 5 x 106 cm(-2) illustrated high quality of the thick film on template. The photoluminescence spectrum of GaN film on the MOCVD-template showed the narrowest line-width of the band edge emission in comparison with other two growth modes.

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随着隐私保护越来越为人们所关注,对匿名认证技术的研究已经成为学术领域的一个热点。本文主要着眼于匿名认证中的匿名凭证与匿名口令认证密钥协商。 在对匿名凭证技术的研究中,本文重点分析了防止凭证出借与凭证匿名更新两个匿名凭证系统性质的实现。 凭证出借是指匿名凭证系统中,用户可以随意将自己的凭证与他人共享,从而使多人可以同时使用一个凭证。本文提出一种新的防止凭证出借方法,并给出一个具体的实现方案。该方法将凭证出借与用户隐私联系起来,通过凭证本身实现防止凭证出借。凭证匿名更新则是指凭证内容进行更新时,凭证颁发方只能知道变更的内容信息,不知道其他任何信息。本文提出一种新的实现方法,在原有凭证的基础上,用相对较少的计算量来实现对凭证内容的更新,使用户匿名得到一个新的凭证。 在对匿名口令认证密钥协商的研究中,本文首先提出了两个攻击方案:针对Shin等人的TAP(t≥2)协议的内部假扮攻击和针对TAP(t≥2)协议以及Viet等人的k-out-of-n APAKE协议的离线字典攻击。前者破坏了协议的认证性,内部攻击者可以假扮服务器与用户建立会话密钥。后者破坏了协议最基本的对口令的安全保护,使得内部攻击者可以离线猜测组内所有用户口令。然后,本文提出了一个新的两方的匿名口令认证密钥协商协议:NAPAKE,并在Square Computational Diffiee-Hellman困难假设以及Decision Inverted-Additive Diffie-Hellman困难假设下证明其安全性。同时,还进一步将其扩展为D-NAPAKE协议,以实现多方的匿名口令认证密钥协商,该协议可以抵抗上面的两个攻击。

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我国电池生产量已经达到209亿节(2003年),多年来一直占据世界第一大电池生产国的地位,其中锌锰电池占大多数。废锌锰电池丢弃后,其中的重金属物质会逐渐渗透到地下,污染土壤和水体。重金属在生物体内富集,会使生物体致畸或致变。但同时,废锌锰电池中也含有大量有用的资源如锌、二氧化锰等。应对其进行回收利用,变废为宝。本文介绍了废锌锰电池回收处理的主要技术及研究进展,不同的处理技术回收废锌锰电池时的目标产物各不相同,但一般可分为以下几种:以单质形式回收锌、锰和汞;以合金的形式回收锌和锰;回收锌和二氧化锰;回收各金属元素制备复合微量元素肥料;回收锌、锰元素制备锰锌铁氧体;回收锌、锰元素制备硫酸锌和碳酸锰等。本文对一些废锌锰电池回收处理技术的优缺点从无害化程度、资源化程度、产品等级、工艺要求以及二次污染五个方面进行了分析和比较。在对国内外废锌锰电池回收处理技术进行分析比较的基础上提出了一种成本较低、可操作性较强的处理技术:先以干法除去废锌锰电池中的汞,然后以湿法除去其它的有害重金属并进一步加工制备有机螯合微量元素肥料。 本文以回转窑中物料停留时间的经验公式和传热学的知识设计和计算了回转窑的长度和内径尺寸、电热丝的功率以及外围的保温材料厚度等参数。用保温材料和润滑油相结合的方式对回转窑的连接部分实行密封。通过调整回转窑的转速和回转窑支架两端高度差的方式控制物料在回转窑中的停留时间,从而调节热解时间的长短。利用自动控制设备调节电热丝的功率从而调节试验中的热解温度。利用该回转窑在不同条件下对热解处理废锌锰电池进行了试验研究,热解过程中产生的尾气和颗粒物用一系列吸收液进行吸收和固定。 在热解试验中改变影响热解过程的三种因素:热解温度、热解时间和载气流速并按三因素四水平的正交方法安排试验。改变废锌锰电池热解过程中的热解温度、热解时间和载气流速三种因素进行正交试验并利用正交统计学的方法分析了这三种因素对热解除汞率的影响。利用ICP检测仪测定了各吸收液中汞的含量,并分析热解气体产物经过系列吸收液时汞被吸收的情况以及汞的形态分布。利用气相色谱仪对尾气成分进行了测定,并对热解过程中产气的过程和规律进行了分析。用X射线衍射测试的方法研究了热解前后锌锰电池的物质形态变化情况。对除汞率的正交统计分析表明,合适的热解条件为:热解温度690℃,热解时间100min,载气流速0.06m3/h,在这种试验条件下热解处理废锌锰电池的除汞率达到100%。同时还得到:热解时间对除汞效果影响最大,热解温度次之,载气流速的影响较小。ICP测试的结果表明:热解尾气在经过试验中设置的吸收瓶后,其中的汞被完全吸收,尾气中95%以上的汞以单质的形式存在。气相色谱分析的结果表明,热解开始后,废锌锰电池中的有机质迅速分解,其产物为C2H4、CH4和H2等。一段时间后,有机质的分解量大幅度减少,同时废电池中的石墨碳和高价金属氧化物发生氧化还原反应,生成CO气体。对废锌锰电池原料以及热解残渣的X射线衍射分析表明,当热解温度为350℃时,X射线衍射图谱上2θ值为35°附近的区域有新峰出现,但不明显,说明有结晶体形成但量不大。500℃时上述峰明显增强,这是由于ZnO和FeO形成了结晶体,同时在2θ值为41°附近有新峰出现,这是高价锰氧化物与石墨碳发生氧化还原反应生成了MnO并形成了结晶体。650℃时,2θ值在41°附近的峰显著增强,且热解过程中形成的峰稳定下来,基本上不再有新的结晶体生成。热解后,高价锰氧化物的相对含量从32.2%下降到4.6%,而MnO的相对含量则从6.4%上升到38.6%。热解后的残渣中晶体物质含量大,金属元素大多以低价态存在,适合于制备有机螯合微量元素肥料。

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介绍国内外连续流动式聚合酶链式反应生物芯片/微装置中脱氧核糖核酸样品的驱动控制技术进展,主要包括恒流泵(注射泵驱动和蠕动泵驱动)、旋转泵驱动、磁流体动力驱动以及自然对流驱动等。并对这几种驱动方式的优缺点作简要的讨论(引用文献43篇)。


A review of the recent progress of actuation control technique of DNA samples in micro-device of continuous-flow polymer ase chain reaction biochip,Covering mainly the years from 1985 tO 2006 was presented in this paper,pertaining especially to the actuation by constant flow pumps(actuated with injection pump and peristaltic pump),by rotary pump,and magnetohydrodynamic actuation and natural convection actuation;and a brief discussion On the merits and defects of various ways of actuation was also given(43 ref.cited).

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本论文以聚苯乙烯(PS)一聚丁二烯(PB)三嵌段和二嵌段共聚物体系为研究对象,利用聚合物的软有序化,控制聚合物分子链的取向和聚集条件,系统地考察了嵌段共聚物在由溶液成膜的过程中动力学效应和墒效应对其相结构和相转变行为的影响。并探讨了不同相结构和其力学性能之间的构效关系。设计了聚苯乙烯(PS)一聚丁二烯(PB)(PS≈30wt%)/非选择性溶剂体系,通过改变溶剂的挥发速率,控制了嵌段共聚物薄膜相结构形成的动力学过程。在快速挥发的条件下,在嵌段共聚物中观察到了特殊的反转相结构,即共聚物中含量多的组分(PB)形成了分散相,而当溶剂挥发很慢的条件下,得到的是热力学较稳定的正常相的结构。对不同分子量的一系列嵌段共聚物的研究表明,反转相的形成和分子量相关,与聚合物的链段数目无关,只有在低于临界分子量 (Mw=70-100 KDa)的嵌段共聚物中,成膜过程的动力学过程才影响嵌段共聚物薄膜的最终相态,即形成反转相。这种依赖于分子量的相转变行为,揭示了分子链运动速度与环境变化速率的匹配对嵌段共聚物薄膜有序相结构形成的重要作用,即动力学效应对聚合物软有序化的重要作用。利用冷冻干燥的方法,进一步研究了嵌段共聚物在极慢的溶剂挥发下,由溶液膜变成固体膜的过程中,随着溶液浓度的增加,不同聚合物分子链在溶液中自组织形成有序结构的过程。结果表明反转相是由稀溶液向亚浓溶液转变的过程中形成的。通过选取具有代表性的不同亲和性的溶剂:苯和环己烷及其混合溶剂,研究了溶剂对不同链段亲和性的差异对反转相形成的影响。由聚合物一溶剂相互作用参数判断,苯是体系的良溶剂,环己烷是体系的。溶剂,而苯对PS链段有较好的亲和性,与之相反环己烷对PB链段有较好的亲和性,通过对聚苯乙烯(PS)一聚丁二烯印B)二嵌段共聚物在苯和环己烷极其混合溶剂中的相转变行为的研究发现,随着溶剂对含量少的PS链段亲和性的降低,反转相不再出现。这是由于苯与PS.链段、环己烷与PB链段有更好的亲和性,嵌段共聚物在稀溶液中,在耗尽吸引的(depletion attraction)作用下,与溶剂亲和性弱的链段,在溶液中优先发生聚集,而有序聚集后导致的混合熵的损失会被更多的因有序聚集后小分子自由体积增加引起的平移嫡的增量所补偿,因此导致了嫡驱动的软有序化。最后,通过原子力显微镜纳米压印法,分别对反转相和正常相结构的纳米力学性能进行了对比研究,讨论了不同相结构间模量的差异,结果表明软段(PB)形成分散相结构时薄膜的模量总是小于硬段(PS)形成分散相结构时薄膜的模量,这主要是由嵌段共聚物不同组分的相对含量及形成的相的结构决定的。

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Quantum-dot laser diodes (QD-LDs) with a Fabry-Perot cavity and quantum-dot semiconductor optical amplifiers (QD-SOAs) with 7° tilted cavity were fabricated. The influence of a tilted cavity on optoelectronic active devices was also investigated. For the QD-LD, high performance was observed at room temperature. The threshold current was below 30 mA and the slope efficiency was 0.36 W/A. In contrast, the threshold current of the QD-SOA approached 1000 mA, which indicated that low facet reflectivity was obtained due to the tilted cavity design.A much more inverted carrier population was found in the QD-SOA active region at high operating current, thus offering a large optical gain and preserving the advantages of quantum dots in optical amplification and processing applications. Due to the inhomogeneity and excited state transition of quantum dots, the full width at half maximum of the electroluminescence spectrum of the QD-SOA was 81.6 nm at the injection current of 120 mA, which was ideal for broad bandwidth application in a wavelength division multiplexing system. In addition, there was more than one lasing peak in the lasing spectra of both devices and the separation of these peak positions was 6-8 nm,which is approximately equal to the homogeneous broadening of quantum dots.

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The high cycle and Very-High-Cycle Fatigue (VHCF) properties of a structural steel with smooth and notched specimens were studied by employing a rotary bending machine with frequency of 52.5 Hz. For smooth specimens, VHCF failure did occur at fatigue cycles of 7.1 x 10(8) with the related S-N curve of stepwise tendency. Scanning Electron Microscopy (SEM) was used for the observations of the fracture surfaces It shows that for smooth specimens the crack origination is surface mode in the failure regime of less than 10(7) cycles While at VHCF regime, the material failed from the nonmetallic inclusion lies in the interior of material, leading to the formation of fisheye pattern. The dimensions of crack initiation region were measured and discussed with respect to the number of cycles to failure. The mechanism analysis by means of low temperature fracture technique shows that the nonmetallic inclusion in the interior of specimen tends to debond from surrounding matrix and form a crack. The crack propagates and results to the final failure. The stress intensity factor and fatigue strength were calculated to investigate the crack initiation properties. VHCF study on the notched specimens shows that the obtained S-N curve decreases continuously. SEM analysis reveals that multiple crack origins are dominant on specimen surface and that fatigue crack tends to initiate from the surface of the specimen. Based on the fatigue tests and observations, a model of crack initiation was used to describe the transition of fatigue initiation site from subsurface to surface for smooth and notched specimens. The model reveals the influences of load, grain size, inclusion size and surface notch on the crack initiation transition. (C) 2010 Elsevier Ltd. All rights reserved

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赤霉素是一种高效能的广谱植物生长调节剂,为五大植物激素之一,具有重要的生物学功能。目前利用赤霉素突变体研究生物合成途径和信号转导已经成为热点。 GA 20-氧化酶是GA生物合成中的一类关键酶,它位于GA合成途径的中心位置。本研究根据烟草(Nicotiana tabacum)GA 20-氧化酶基因序列,设计2对分别含有特定酶切位点的特异引物,以烟草基因组DNA为模板,扩增目的基因(约250 bp)片段。将正、反向目的片段分别插入中间载体的内含子两侧,再经BamH I和Sac I双酶切回收约700 bp的目的片段,插入到双元载体质粒p2355中,成功构建了含GA 20-氧化酶基因片段反向重复序列的植物表达载体p23700。分别将p2355质粒和p23700质粒导入根癌农杆菌(Agrobacterium tumefaciens)EHA105中并转化烟草叶片细胞,经卡那霉素选择培养,PCR及GUS组织染色鉴定,获得转基因烟草植株。以EHA105-p2355转化的烟草,获得41株转基因植株,均没有矮化表型;而以EHA105-p23700转化的烟草,获得转基因植株14株,其中具有矮化表型的烟草10株,表明反向重复序列转录产物能形成发夹RNA(hpRNA),产生小分子干扰RNA(small interferring RNA,简称siRNA),干扰目的基因的表达。 赤霉素含量测定表明矮化植株中赤霉素合成途径的最终产物GA3总含量明显低于野生型烟草植株。荧光定量PCR结果表明,矮化转基因烟草的GA 20-氧化酶基因表达量受到明显抑制,表达量明显低于野生型对照。同时对上游内根-贝壳杉合成酶(Ent-kaurene synthase,KS)基因,下游的GA-3β羟化酶基因进行了RT-PCR分析,结果显示上游基因的表达没有规律性变化,而下游基因表达量亦降低。上述结果表明,GA 20-氧化酶基因的表达被有效地干扰了,表达受到抑制,从而影响植株体内GA3的合成,影响植株的生长发育,导致植株矮化。并推测,GA 20-氧化酶基因受到抑制,可能影响下游基因的表达。并且通过干旱胁迫测试,发现矮化植株相对于野生型植株及不含干扰片段的转基因植株,对干旱的耐受力有了很大的提高,具有更强的耐受力。 研究结果为进一步进行相关研究奠定基础。 Gibberellin(GA) is an efficient plant growth regulator. As one of five major plant hormones, it plays an important biological function. Using GA mutant for investigating biosynthetic pathways and signal transduction has become high lights. GA 20-oxidase is a crucial enzyme involved in gibberellin biosynthesis. According to tobacco (Nicotiana tabacum) GA 20-oxidase enzyme gene sequence and based on binary vector p2355, we constructed a plant expression vector p23700, which habors an inverted repeat DNA fragment of GA 20-oxidase gene drivered by Cauliflower mosaic virus promtor (CaMV 35Sp). Binary plasmid p2355 had no inverted repeat DNA fragment of GA 20-oxidase gene. The vector p2355 and p23700 were introduced into Agrobacterium tumefaciens EHA105 and tobacco leaf transformation was conducted. After selected by kanamycin and characterized by PCR and GUS hischemical reaction, transsgenic plants were obtained. Fourtheen transgenic plants, which were transformed by EHA105-p23700, were obtained. Among them, 10 were dwarf mutants. However, 41 transgenic plants with the same normal phenotype as wild type,which were transformed by EHA105-p2355, were obtained. Analysis of Gibberellin contents showed that it was lower in dwarf mutants than in normal phenotype plants. Moreover, comparing to normal phenotype plants including wild type and transgenic plants with no interference fragment, the drought tolerance of dwarf plants have greatly increased. And their proline content increased obviously after drought test. Fluorescence quantitative real time PCR (RT-PCR) showed that GA 20-oxidase gene expression was significantly inhibited in dwarf transgenic tobacco. Meanwhile, the expression of the upstream gene ent-kaurene synthase (KS) gene and downstream gene GA-3β hydroxylase gene was also detected by RT-PCR. The results presented that KS gene expression had no regular change while GA-3β hydroxylase gene expression reduced. It implied that inhibiting GA 20-oxidase gene probably reduce the expression of downstream genes. The results showed that the transcriptional products of the foreign inverted repeat fragment can form hairpin RNA (hpRNA) to induce RNAi. It presented that GA 20-oxidase gene expression was effectively interfered, resulting in reducing GA3 synthesis and inhibiting plant growth and development, then dwarf plants were produced. However, the dwarf plants had higher tolerance of drought.

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本文根据我们实验室建立的发酵产物中辅酶Q10定性定量检测方法,筛选得到一株可以代谢产生较多辅酶Q10的野生菌株放射形土壤杆菌(Agrobacterium radiobacter No.50)。 为了提高放射形土壤杆菌的辅酶Q10的产量,本实验利用液体培养研究了单因素对菌株辅酶Q10产量的影响,并用正交法确定了最佳液态发酵条件。最佳发酵培养基是:葡萄糖20g,蔗糖40g, 硫酸铵10g,玉米浆30g, 酵母膏3g,K2HPO4 3g,MgSO4.7H2O 1g,蒸馏水1000mL,pH 7.0-7.2。最佳发酵条件是:转接斜面菌种到种子培养基, 转速220r/min、温度28。C培养24h后,转入发酵培养基(250mL三角拼装液量为50mL,pH 7.0), 接种量为10%,转速220r/min、温度28。C,培养120h。在此条件下,菌体湿重约为50g/L,辅酶Q10含量约为20mg/L。 本文以放射形土壤杆菌为出发菌株进行诱变育种,以期获得辅酶Q10高产菌。根据微生物育种原理、参照辅酶Q10的代谢调控机制,以野生型放射形土壤杆菌(Agrobacterium radiobacter No.50)为出发菌株,采用紫外线和亚硝基胍复合诱变技术,依次筛选得到菌体提取物M抗性菌ARM-7、烟草提取物T抗性菌株ARMT-26、Vk3抗性菌株ARMTV-25、链霉素抗性菌株ARMTVS-32,菌株ARMTVS-32产量达到了36.8mg/L,与原始出发菌株相比,产量提高了77%。 研究了茄尼醇、对羟基苯甲酸、橘子皮提取物D、胡萝卜提取物E、烟草提取物对ARMTVS-32合成辅酶Q10的影响,结果表明这些物质对菌体合成辅酶Q10有一定促进作用,添加0.2g/L茄尼醇时,辅酶Q10含量提高了17%,达到了40.7mg/L;添加1.2g/L橘子皮提取物D时,辅酶Q10含量提高了13.8%,达到了39.6mg/L;添加0.5g/L胡萝卜提取物E时,辅酶Q10含量提高了25.3% ,达到了43.6mg/L;添加8g/L烟草提取物时,辅酶Q10含量提高了12.6%,达到了39.2mg/L。 Production of Coenzyme- Q10 (CoQ10) by fermentation is considered as a process with broad prospects.Quantitative Analysis of CoQ10 in the culture of microbe by TLC—UV spectrophotometry was developed, by using this method we got the strain Agrobacterium radiobacter,which was isolated from forest soil of southwest of China. The effect of the single factor on CoQ10-production ability of the strain was examined by liquid cultured, and its best optimum cultivation conditions were established by orthogonal method. The results showed that the optimum fermentation conditions were as following: carbon sources glucose 20g/L,sucrose 40g/L; nitrongen sources (NH4)2SO4 10g/L,maize liquid 30g/L;yeast extract 3g; K2HPO4 3g/L,MgSO4.7H2O 1g/L; initial pH was 7 and volume of medium(medium volume vs flask volume) was 50mL/500mL, incubating for 120h on a rotary shaker at 220 rpm and 28℃.Under these conditions, the biomass and CoQ10 concentration reached 50g/L and 20mg/L respectively. According to the biosynthesis mechanism of CoQ10 and breeding theory, CoQ10 over-production strains were screened by UV--NTG. mutation using Agrobacterium radiobacter No.50 as parent strain. A microbe-juice resistant mutant ARMTVS-32, which also could resist tobacco-juice, VK3 and streptomycin, was screened out from an agar plate. The CoQ10 content of ARMTVS-32 reached 36.8mg/L, which was 77% higher than the initial strain. In addition, We discussed the effects of some organic substrates on the synthesis of CoQ10 in ARMTVS-32. The results showed that solanesol, orange juice D, carrot juice E and tobacco juice could promote the CoQ10 accumulation in the cells. The CoQ10 content of ARMTVS-32 reached 40.7mg/L when added 0.2g/L solanesol,it reached 39.6mg/L when added 1.2g/L orange juice D,it reached 43.6mg/L when added 0.5g/L carrot juice E. it reached 39.2mg/L when added 8g/L tobacco juice.

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BACKGROUND: Hypoxia and ischemia induce neuronal damage, decreased neuronal numbers and synaptophysin levels, and deficits in learning and memory functions. Previous studies have shown that lycium barbarum polysaccharide, the most effective component of barbary wolfberry fruit, has protective effects on neural cells in hypoxia-ischemia. OBJECTIVE: To investigate the effects of Naotan Pill on glutamate-treated neural cells and on cognitive function in juvenile rats following hypoxia-ischemia. DESIGN, TIME AND SETTING: The randomized, controlled, in vivo study was performed at the Cell Laboratory of Lanzhou University, Lanzhou Institute of Modern Physics of Chinese Academy of Sciences, and Department of Traditional Chinese Medicine of Gansu Provincial Rehabilitation Center Hospital, China from December 2005 to August 2006. The cellular neurobiology, in vitro experiment was conducted at the Institute of Human Anatomy, Histology, Embryology and Neuroscience, School of Basic Medical Sciences, Lanzhou University, and Department of Traditional Chinese Medicine of Gansu Provincial Rehabilitation Center Hospital, China from March 2007 to January 2008. MATERIALS: Naotan Pill, composed of barbary wolfberry fruit, danshen root, grassleaf sweetflag rhizome, and glossy privet fruit, was prepared by Gansu Provincial Rehabilitation Center, China. Rabbit anti-synaptophysin, choline acetyl transferase polyclonal antibody, streptavidin-biotin complex kit and diaminobenzidine kit (Boster, Wuhan, China), as well as glutamate (Hualian, Shanghai, China) were used in this study. METHODS: Cortical neural cells were isolated from neonatal Wistar rats. Neural cell damage models were induced using glutamate, and administered Naotan Pill prior to and following damage. A total of 54 juvenile Wistar rats were equally and randomly assigned into model, Naotan Pill, and sham operation groups. The left common carotid artery was ligated, and then rat models of hypoxic-ischemic injury were assigned to the model and Naotan Pill groups. At 2 days following model induction, rats in the Naotan Pill group were administered Naotan Pill suspension for 21 days. In the model and sham operation groups, rats received an equal volume of saline. MAIN OUTCOME MEASURES: Neural cell morphology was observed using an inverted phase contrast microscope. Survival rate of neural cells was measured by MTT assay. Synaptophysin and choline acetyl transferase expression was observed in the hippocampal CA1 region of juvenile rats using immunohistochemistry. Cognitive function was tested by the Morris water maze. RESULTS: Pathological changes were detected in glutamate-treated neural cells. Neural cell morphology remained normal after Naotan Pill intervention. Absorbance and survival rate of neural cells were significantly greater following Naotan Pill intervention, compared to glutamate-treated neural cells (P < 0.05). Synaptophysin and choline acetyl transferase expression was lowest in the hippocampal CA1 region in the model group and highest in the sham operation group. Significant differences among groups were observed (P < 0.05). Escape latency and swimming distance were significantly longer in the model group compared to the Naotan Pill group (P < 0.05). CONCLUSION: Naotan Pill exhibited protective and repair effects on glutamate-treated neural cells. Naotan Pill upregulated synaptophysin and choline acetyl transferase expression in the hippocampus and improved cognitive function in rats following hypoxia-ischemia.

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An apparatus including a rotary-type injector was designed for quantitative sample injection in capillary electrophoresis (CE), in which both pressurized flow and electroosmotic flow were used to drive the background electrolyte solution. A relative standard deviation of peak area of lower than 1% was achieved by using this apparatus. The effects of back-pressure regulator, restrictor, and applied voltage on separation efficiency and resolution were investigated. The utility of this apparatus in both micro-HPLC and pressurized capillary electrochromatography (pCEC) was also demonstrated.