Development of a functional cell-based HTS assay for identification of NKCC1-negative modulators

Na–K–Cl cotransporter 1(NKCC1) cotransports Na+, K+, and Cl-ions across the plasma membrane into cells. Accumulation of Cl-ions in dorsal root ganglion neurons induces depolarizing GABAA receptors, which mediate presynaptic inhibition and filtration of sensory noise. The activity of the Na–K–Cl cotransporter is modulated by high-dose loop diuretics, such as furosemide and bumetanide. To identify NKCC1 modulators, we developed a functional cell-based assay feasible for highthroughput screening(HTS), in which the activity of NKCC1 was detected by a BTC-AM dye-based thallium transportation assay. We demonstrated that the influx of Tl?was mediated by NKCC1, which required the existence of Cl-ions and could be inhibited by bumetanide and furosemide. Our results demonstrated that the assay was stable, reproducible, and suitable for HTS of negative modulators for NKCC1.     

GaN-based substrates and optoelectronic materials and devices

In order to solve the problems of GaN heteroepitaxy on sapphire substrate,some techniques were explored.Freestanding GaN substrates have been made by hydride vapor phase epitaxy(HVPE),laser lift-off(LLO),and chemical mechanical polishing techniques.Wafer bending and cracking in the HVPE growth were partly settled by pulsed flow modulation method.High-crystal quality was established for 1.2 mm thick GaN substrate by X-ray diffraction measurement,in which the full width of half maximum values were 72,110 arcsec for(102),(002)peaks.A novel micro-size patterned sapphire substrate(PSS)and a nano PSS were also fabricated.High-power vertical structure light emitting diodes(VSLEDs)have been developed by Au–Sn eutectic wafer bonding,homemade micro-area LLO,and light extraction structure preparation.The high-injection-level active region with low temperature GaN sandwiched layers was used for lowefficiency droop.The light output power of VSLED was achieved as 400 mW driven at 350 mA,and the dominant wavelength is about 460 nm.The structures and properties of strain modulated superlattices(SLs)and quantum wells as well as advanced simulation of carriers transport across the electron blocking layer were investigated in laser diodes.The hole concentration was achieved as high as1.6 9 1018cm-3in AlGaN/GaN SLs:Mg by inserting an AlN layer.High-quality AlGaN epilayers and structures were grown by MOCVD.Some device structures of UV LEDs and detectors were demonstrated.The emission wavelength of 262 nm UV LED has been successfully fabricated.At last,high-quality InN and InGaN materials for solar cell were grown by boundary-temperature-controlled epitaxy and growth-temperature-controlled epitaxy.Hall-effect measurement showed a recorded electron mobility of 3,280 cm2/(V s)and a residual electron concentration of 1.47 9 1017cm-3at 300 K.     

氧化石墨烯/磷酸钙生物水泥体外生物相容性研究

等摩尔的Ca_3(PO_4)2-CaHPO_4-CaCO_4(CPCs)水泥系为固相,不同质量浓度的氧化石墨烯(GO)水分散液(0~24mg/mL)为液相,按一定的固液比固化,得到复合材料GO/CPCs.以成骨细胞MC3T3-E1为对象,初步探究该复合材料试样的体外生物相容性.扫描电镜观察细胞贴壁形态,MTT法评价细胞活力,碱性磷酸酶(ALP)活性检测探讨材料的骨诱导性.结果显示:MC_3T3-E1细胞在材料表面状态良好,产生胞质突;GO的添加能够增强MC3T3-E1细胞活力;GO/CPCs在短期内(1d)促进MC3T3-E1细胞早期分化.GO/CPCs有望成为一种新型骨组织替代材料.     

Synthesis of novel superhard materials under ultrahigh pressure

Superhard materials are solids whose Vickers hardness is beyond 40 GPa. They have wide applications in industry such as cutting and polishing tools, wear-resistant coatings. Most preparations of superhard materials are conducted under extreme pressure and temperature conditions, not only for scientific investigations, but also for the practical applications. In this paper, we would introduce the recent progress on the design and preparations of novel superhard materials, mainly on nanopolycrystalline diamond, B–C–N superhard solid solutions, and cubic-Si3N4/diamond nanocomposites prepared under ultrahigh pressure and high temperature（HPHT）, using multi-anvil apparatus based on the hinged-type cubic press. Bulk materials of all these superhard phases have been successfully synthesized and are systematically tested. We emphasize that ultra-HPHT method plays an important role in the scientific research and industrial production of superhard materials. It provides the driving forces for the light elements forming novel superhard phases as well as the way for sintering high-density nanosuperhard materials.     

低强度脉冲超声对MC3T3-E1细胞增殖、分化和矿化的影响

 为了研究低强度脉冲超声促进MC3T3-E1细胞增殖、分化和矿化的有效性,初步筛选频率和强度参数,分别对细胞施加不同参数(频率、强度)的超声,采取CCK-8法检测细胞的增殖情况,碱性磷酸酶检测试剂盒检测分化效果,茜素红染色观察矿化效果。发现30mW/cm²和40mW/cm²的超声对细胞产生促增殖作用,50mW/cm²抑制增殖;1.5MHz和1.7MHz的较低强度组均较对照组的ALP活性有增加;1.5MHz,40mW/cm²的超声组矿化效果较其他组好。研究结果表明,低强度的脉冲超声可以提高成骨细胞株MC3T3-E1增殖、分化和矿化能力,可能是防治骨质疏松的可行手段之一。     

Ferromagnetic and ferroelectric properties of Aurivillius phase Bi9Fe4.7Me0.3Ti3O27（Me 5 Fe,Co, Ni,Mn）

New Aurivillius phase Bi9Fe4.7Me0.3Ti3O27（Me = Fe, Co, Ni, Mn） oxides have been prepared using a citrate combustion method. X-ray diffraction on powders and high-resolution transmission electron microscopy investigation confirmed that the Bi9Fe4.7Me0.3Ti3O27 samples are with an eight-layer structure. Both ferromagnetic and ferroelectric investigations suggested that Co or Ni substitution could enhance their multiferroic properties,while Mn substitution depressed them. Among all the samples, Bi9Fe4.7Co0.3Ti3O27 sample exhibits the largest remnant polarization of Pr＊3.8 l C/cm2, and the largest remnant magnetization of Mr＊0.06 lB/f.u. with a Curie temperature about 764 K, while the Bi9Fe4.7Ni0.3Ti3O27 sample has the largest spontaneous magnetization（0.26 lB/f.u.）. The improved ferromagnetic properties ofboth Bi9Fe4.7Co0.3Ti3O27 and Bi9Fe4.7Ni0.3Ti3O27 can be ascribed to the spin canting of magnetic ion-based sublattices via the Dzyaloshinskii–Moriya interaction and also the magnetic ions exchanging interactions（Fe3–O–Co3or Fe3–O–Ni3）.     

采用软化学法制备WO3和其锂化物及其结构稳定性的研究

通过两种方法合成了六方形和单斜氧化钨的水化物WO3·yH2O(y=0.50～1.20):(1) 用强酸(1～3 mol/L HCl) 将0.25 mol/L Li2WO4在100 ℃进行酸化; (2) 将1 mol/L Li2WO4置于高压反应釜中,控制pH为1.5,在100 ℃进行水热合成. 对于水热法,温度较高时(125～200℃),得到组分为LixWO3+x/2·yH2O(x=0.10～0.50,y=0.50～0.90)的锂化氧化钨. 合成产物的结构和组分与酸的浓度和后处理(加热、超声波)有关. 在350 ℃加热时六方形氧化钨完全转化为单斜氧化钨. 将温度在150 ℃以上时通过水热法合成的氧化钨前驱体进行超声波处理,产物的含锂量恒定为每单元0.18摩尔. 锂的引入有利于锂化氧化钨的结构和组分的稳定.     

Structural phase transition and metallization in compressed SrC_2

The structural, dynamical, and electronic properties of compressed Sr C2 were systematically investigated up to 200 GPa by using ab initio method. Three new phases are obtained by means of evolutionary algorithm. The confirmed most stable structure has C2/c symmetry at zero pressure, which transforms into an orthorhombic Cmcm phase at 4.5 GPa, followed by another orthorhombic Immm phase, which is stabilized at wide pressure range of 21.5–123.5 GPa, and then transformed into Mg B2-type phase（space group, P6/mmm）. Although Sr C2 has similar structural transformation to that of compressed Ca C2, Sr C2 holds small electron–phonon coupling,which leads to its low superconducting critical temperature（only 1.8 K）.     

绿色人才培养中存在的问题及解决对策

随着可持续观念的发展,环境教育已成为提高我国全民族思想道德素质和文化素质的基本手段之一,绿色人才应运而生。本文概括了绿色人才的含义,在分析绿色人才培养中存在问题的基础上,提出了建立专业化绿色学校、培养知识型绿色人才、争取政府的引导与支持、重视网络信息的传播作用等解决对策。     

职业教育教学探析

我是一名在教学一线工作的专任教师,本人认为教学模式及教学方法应该与时俱进,首先我认为应该强调每一个老师要从单纯注重传授知识转变为引导学生学会学习,学会合作,学会做人。其次要着重培养学生具有社会责任感、实践能力和良好的综合素养等。第三要关注学生思想品德等多方面的发展。     

架空输电线路应用摄影测量技术分析

随着摄影测量技术的成熟和发展,在架空输电线路工程中的应用摄影测量技术得到广泛重视。本文对摄影测量在架空输电线路中的应用现状进行分析和总结,并对其发展趋势提出一点看法。     

浅议配电系统中供电可靠性

配电系统是直接连接用户的系统,其供电可靠性对用户有着重要的影响。本文对配电系统的影响供电可靠性的因素、可靠性分析内容以及提高系统供电可靠性的措施等方面进行了研究。     

浅议我国网上银行的金融监管

网上银行作为21世纪一种新兴的金融业,其低廉的成本和广阔的前景,已越来越得到人们的重视。货币数字化和网络支付体系已经成为当今银行业的操作基础。随着信息化的飞速发展,网上银行在带给人们优质、快捷、全面服务的同时,这种以信息流为主的模式,也对实施金融监管提出了强有力的挑战。本文从网上银行的特征及我国网上银行的发展现状出发,深入分析我国网上银行发展对金融监管的冲击,并提出适时地金融监管对策。     

论翻译批评对读者的关注

我国当前的翻译批评“量少质次”,主要囿于“文本批评”,对作为翻译接受主体的读者关注不够。本文首先指出关注读者乃翻译批评的固有之义,接着探讨了翻译批评理应对待读者的态度以及关注读者的主要方面。     

新课程下中学政治课教学的创新

新课程的改革脚步已进入了中学课堂教学,并不断地深入和发展。教师在教学中要着重开发学生的创造潜能,把发展创造力作为教学核心,培养学生的探索精神,培养自学能力,让课堂充满着跳跃的音符,创造的活力。建立新型师生关系,设置创新环境;激发学生学习兴趣,培养创新意识;营造课堂“敢问”氛围,培养质疑能力;鼓励学生求异发散思维;注重社会课堂实践,完善创新能力。     

Multiferroic and magnetoelectric properties of La0.1Ba0.9Fe12O19 ceramics

La0.1Ba0.9Fe12O19 powders with similar hexagonal crystal structure to Ba Fe12O19 have been successfully synthesized using polymer precursor method. The powders were suppressed into pellets, which were sintered into ceramics at 1,300 °C for 1 h. The structure and morphology of the ceramics have been determined by X-ray diffraction（XRD） and field emission scanning electron microscopy（FESEM）. Clear electric hysteresis loops upon different amplitude of external fields indicates that La0.1Ba0.9Fe12O19 is a kind of possible ferroelectric compound. The maximum remnant polarization of La0.1Ba0.9Fe12O19 ceramic is estimated to be ＊9.6 l C/cm2. The Fe O6 octahedron in its perovskite-like hexagonal unit cell as well as the shift of Fe3？off the center of octahedron are proposed to be the origin of electric polarization in La0.1Ba0.9Fe12O19. Simultaneous occurrence of large ferroelectricity and strong ferromagnetism has been observed in La0.1Ba0.9Fe12O19 ceramics. More interestingly, this compound demonstrates electronic polarization behavior being actuated by an applied magnetic field, indicating the existence of magnetoelectric（ME） coupling effect in the La0.1Ba0.9Fe12O19 ceramics. Our results may lead to new device applications such as magnetically recorded ferroelectric memory.     

Cellular response to titanium discs coated with polyelectrolyte multilayer films

The purpose of this study was to investigate the effects of polyelectrolyte multilayer (PEM) coatings on the biological behavior of titanium (Ti) substrates. Collagen type Ι/hyaluronic acid (Col/HA) and chitosan/hyaluronic acid (Chi/HA) multilayer PEM coatings were introduced onto Ti substrates using layer-by-layer assembly. Contact angle instruments and quartz crystal microbalance were used for film characterization. The results obtained showed that both Col/HA and Chi/HA surfaces had high hydrophilicity and promoted cell adhesion in MC3T3-E1 pre-osteoblast and human gingival fibroblast cells. In addition, the synthesis of function-related proteins and gene expression levels in both MC3T3-E1 and fibroblast cells was higher for the Col/HA coating compared with the Chi/HA coating, indicating better cellular response to the Col/HA coating.     

一个IP建多个Web站点——TCP端口法

气象网站是气象部门对外气象服务的一个窗口。在这个高度信息化的社会里,建立县级台站自己的网站是最直接、最有效的服务及宣传手段。目前当地网络运营商只为县级台站提供了一个固定的IP地址,且在中小型局域网中,县级台站服务器往往只有一台,但是一个Web站点显然又无法满足工作需要。那么,能否在一台服务器上设置多个Web站点呢？答案是肯定的,并有多种途径可以达到这一目的。我们知道,网络上的每一个Web站点都有一个惟一的身份标识,从而使客户机能够准确地访问。这一标识由三部分组成,即TCP端口号、IP地址和主机头名,要实现＂一机多站＂就需要在这三个方面下工夫。本文将以例子的形式介绍＂TCP端口号＂法。     

浅谈体育教学中安全事故的预防

体育教育是以身体活动为主的学习过程,教学中如稍有考虑不周,就易发生损伤类的事故,所以在体育教学中的安全问题显得尤为突出。目前有学校和教师为了尽量避免事故的发生,在体育课中采取一些消极预防办法,如降低教材难度及减负减量,对稍有挑战的教材干脆就去掉,更有甚者仅做一些简单的活动或采取“软禁”的手段敷衍了事,这样既影响了体育教学大纲的贯彻,阻碍了体育教学的发展,也极大影响了学生身体机能的提高。我认为当前学校和教师都应以一个客观的态度去看待体育教学中的安全问题,正确的去对待安全事故,采取有效的办法去减少事故的发生。