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This paper presents experimental optimization of number and geometry of nanotube electrodes in a liquid crystal media from wavefront aberrations for realizing nanophotonic devices. The refractive-index gradient profiles from different nanotube geometries-arrays of one, three, four, and five-were studied along with wavefront aberrations using Zernike polynomials. The optimizations help the device to make application in the areas of voltage reconfigurable microlens arrays, high-resolution displays, wavefront sensors, holograms, and phase modulators. © 2012 Optical Society of America.

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The plant circadian clock is proposed to be a network of several interconnected feedback loops, and loss of any component leads to changes in oscillator speed. We previously reported that Arabidopsis thaliana EARLY FLOWERING4 (ELF4) is required to sustain this oscillator and that the elf4 mutant is arrhythmic. This phenotype is shared with both elf3 and lux. Here, we show that overexpression of either ELF3 or LUX ARRHYTHMO (LUX) complements the elf4 mutant phenotype. Furthermore, ELF4 causes ELF3 to form foci in the nucleus. We used expression data to direct a mathematical position of ELF3 in the clock network. This revealed direct effects on the morning clock gene PRR9, and we determined association of ELF3 to a conserved region of the PRR9 promoter. A cis-element in this region was suggestive of ELF3 recruitment by the transcription factor LUX, consistent with both ELF3 and LUX acting genetically downstream of ELF4. Taken together, using integrated approaches, we identified ELF4/ELF3 together with LUX to be pivotal for sustenance of plant circadian rhythms. © 2012 American Society of Plant Biologists.

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Vision-based object detection has been introduced in construction for recognizing and locating construction entities in on-site camera views. It can provide spatial locations of a large number of entities, which is beneficial in large-scale, congested construction sites. However, even a few false detections prevent its practical applications. In resolving this issue, this paper presents a novel hybrid method for locating construction equipment that fuses the function of detection and tracking algorithms. This method detects construction equipment in the video view by taking advantage of entities' motion, shape, and color distribution. Background subtraction, Haar-like features, and eigen-images are used for motion, shape, and color information, respectively. A tracking algorithm steps in the process to make up for the false detections. False detections are identified by catching drastic changes in object size and appearance. The identified false detections are replaced with tracking results. Preliminary experiments show that the combination with tracking has the potential to enhance the detection performance.

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网络信息技术的发展,改变了专业图书馆的服务方式。在网络环境下,专业图书馆要根据其性质与任务,立足读者的信息需求,加快信息资源馆藏建设,改变信息获取的服务方式;开展联合及信息资源传递服务,实现科技文献资源的共享;建立合理化的网络信息平台,提供学科化信息服务。专业图书馆的创新服务方式包括网络信息导航服务、个性化主动服务、特色化信息服务和课题跟踪服务。

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从2005年9月到2005年10月,利用莲花湖中的3个49m2,深度为1.5m的围隔进行生物水质净化和除藻研究。1#围隔为对照,2#围隔水体中加入无根萍,3#围隔水体中喷洒酵母菌和光合细菌。与1#围隔比较,2#围隔水面的无根萍的数目在300L×5×103 L-1,3#围隔的喷洒复合菌数目酵母菌(300L×4×105L-1)和红螺菌(300 L×8×108 L-1)。本实验结果表明:在30 d内,2#和3#围隔中的TP分别下降40%、25%;TN分别下降43%、16%;叶绿素含量分别下降51%、31%。透明

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湖泊底质中有机物的厌氧代谢产生多种有机酸,其中主要成分是乙酸。研究了暴露于不同浓度的乙酸溶液后伊乐藻(Elodea nuttallii)和菹草(Potam ogeton crispus)无性繁殖体的萌发和幼芽的生长状况。1 mmol/L的乙酸能显著抑制伊乐藻幼芽的生长(p<0.05),但对其繁殖体的萌发无明显影响。在4 mmol/L的乙酸影响下,菹草幼芽仍有明显的生长;菹草繁殖体的萌发受到显著抑制(p<0.05),但在随后的培养中可全部萌发。4 mmol/L以上的乙酸暴露3 d或6 d导致伊乐藻全部死亡,

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本文报道了轮藻科1新种、2新变种及4个中国新记录:不等丽藻 Nitella inaequabilis sP.nov,分叉丽藻齿网变种N.furcata var.dentireticulata var.nov.;普生轮藻等苞变种 Chara vulgaris var.aequibracteata var.nov.;裂顶丽藻 Nitella partita Nordst.;过渡丽藻N.transilis T.F.Allen;布洛丽藻 N.blowiana J.Grove;娇小丽藻 N.pulchella T.

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<正> 鲮鱼[Cirrhina molitorella(Cur.&Val.)]是广东地区饲养的家鱼之一,群众有一套用“大草”养它的经验,但在饲育过程中,鱼苗往往发生一种流行病,导致大量死亡。患病的鱼苗,身体瘦弱,体色发黑,游动缓慢,常浮游在靠近池边的水面上,不久即翻身死亡。情况严重时全池鱼苗能全部死完。但过去并没有引起水产科学工作者的注意。为了提高角苗的成活率和鱼苗的体质,给培育鱼种和饲养成鱼打下更好的基础,对鲮角鱼苗病的研