32 resultados para Iris Pigmentation

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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“欧盟工业风险降低集成系统(IRIS)”是欧盟FP7科技计划项目,旨在将欧盟各个行业风险管理零散的现状,整合成一个全面系统的风险控制方法,建立不同行业之间相关事务的共享平台。本文介绍了项目的立项背景,目标、内容及其焦点问题。

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In this paper, we constructed a Iris recognition algorithm based on point covering of high-dimensional space and Multi-weighted neuron of point covering of high-dimensional space, and proposed a new method for iris recognition based on point covering theory of high-dimensional space. In this method, irises are trained as "cognition" one class by one class, and it doesn't influence the original recognition knowledge for samples of the new added class. The results of experiments show the rejection rate is 98.9%, the correct cognition rate and the error rate are 95.71% and 3.5% respectively. The experimental results demonstrate that the rejection rate of test samples excluded in the training samples class is very high. It proves the proposed method for iris recognition is effective.

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In this paper, from the cognition science point of view, we constructed a neuron of multi-weighted neural network, and proposed a new method for iris recognition based on multi-weighted neuron. In this method, irises are trained as "cognition" one class by one class, and it doesn't influence the original recognition knowledge for samples of the new added class. The results of experiments show the correct rejection rate is 98.9%, the correct cognition rate and the error recognition rate are 95.71% and 3.5% respectively. The experimental results demonstrate that the correct rejection rate of the test samples excluded in the classes of training samples is very high. It proves the proposed method for iris recognition is effective.

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The free living conchocelis of Porphyra yezoensis Ueda was treated with N-methyl-N-nitro-N-nitrosoguanidine to induce pigmentation mutants. The artificial green pigmentation mutant of P. yezoensis conchocelis, which was composed entirely of green cells, was isolated through visualization with the unaided eye. The acquired green conchocelis was further developed into a green gametophytic blade. This mutant was relatively stable in color in both gametophytic blade and conchocelis phases. The gametophytic blade mutant was successively cultivated for commerce at some Porphyra farms in Rudong, China, and few wild type or sectorially variegated gametophytic blade occurred, indicating that the green mutant has commercial value. The green mutant was characterized as having lower phycoerythrin and higher phycocyanin content, and SDS-PAGE suggested that phycoerythrin was missing the gamma-subunit in comparison to the wild type. The wild type and the green mutant showed a clear difference in 02 evolution rates in white, green, yellow, and red light, which might be due to the qualitative and quantitative changes of phycoerythrin, and the quantitative difference of phycocyanin. (C) 2008 Elsevier B.V. All rights reserved.

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The growth and activity of juvenile Japanese eels Anguilla Japonica in different pigmentation stages from the glass eel to the elver stage were studied in the laboratory at 15, 20 and 25degrees C. The growth and activity of the eels were significantly influenced by both temperature and fish size. Growth rate generally declined with increasing fish size, and fish were least active and experienced a low growth during the pigmenting stage at all temperatures. They were nocturnal and spent significantly more time moving (swimming, feeding and moving over the substratum) at 20 and 25degrees C than at 15degrees C at night within each pigmentation stage. Accordingly, they grew significantly Faster at 20 and 25degrees C than at 15degrees C throughout the study. The development of pigmentation appeared to be dependant on water temperature but not on fish size. This study suggested that the growth and activity of juvenile Japanese eels were positively correlated, because fish were least active and grew slowest at low temperature (15degrees C) or during the pigmenting stage at all temperatures. (C) 2003 The Fisheries Society of the British Isles.

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利用我们创建的将兔眼蝉孔水密缝合后,模拟眼内前后房压强差,对虹膜整体进行加压的实验方法,对兔眼虹膜的力学特性进行了实验研究。结果表明:兔眼虹膜是典型的粘弹性物质;面积模量与前后方压强差之间基本成线性关系。实验结果可为青光眼致盲机制解释和瞳孔阻滞力的估算提供参考。

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利用我们创建的将瞳孔水密缝合后,模拟眼内前后房压强差,对虹膜整体进行加压的实验方法,对人眼虹膜的力学特性进行了实验研究。结果表明:人眼虹膜是典型的粘弹性物质;面积模量与前后房压强差之间基本成线性关系。实验结果可为青光眼致盲机制解释和瞳孔阻滞力的估算提供参考。

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本实验用喷施6-BA和茎切生根的方法建立了一套德国鸢尾快速分株繁殖的体系。用3 000 mg/L 或5 000 mg/L 的6-BA 对德国鸢尾(Iris germanica)‘lovely again’进行单次喷施可以促进根茎芽的萌发和根状茎的形成。在喷施后的30 天到90 天内,BA的促进作用在具有2个或4个起始根状茎的植株上表现得很显著,但对于只有一个起始根状茎的植株不显著。在喷施后的150 天以及第二年,具有2个或4个起始根状茎的母株总体上比只具有1个起始根状茎的母株产生了更多的根状茎。而6-BA的喷施对母株的叶面积和叶片数变化没有显著影响。在早春时,把处于不同发育阶段的侧芽或小根茎从母株上取下,并且用不同浓度的IBA处理。总体上,处于较高发育阶段的茎切(芽切)在生根率、初级根和次级根的数目,总根长、根干重以及植株高度等测量指标方面的表现较好。IBA对德国鸢尾的茎切(芽切)的生根作用不显著。多次喷施6-BA 对德国鸢尾根茎芽的生出的促进作用显著,并且使生物量重新分配。连续喷施6-BA后,对内源生长素和细胞分裂素的连续测定结果表明,6-BA的作用主要是解除了顶端优势对侧芽的萌发和生长的抑制,从而形成新的根茎。

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玉蝉花(Iris ensata)、山鸢尾(Iris setosa)、金脉鸢尾(Iris chrysographes)和西南鸢尾(Iris bulleyana)这四种国产野生无髯鸢尾的种子均存在休眠现象,然而萌发情况各异。通过大田实验、层积处理、离体胚培养、切割胚乳、剥离种皮、切割胚乳不同部位、对种子的珠孔端胚乳进行扫描电子显微镜观察和用Instron 5848微力材料实验机测量刺穿珠孔端结构所需要力,以及把离体胚放在PEG-6000的渗透液中来测试四种鸢尾种子胚的生长势等实验,发现:玉蝉花、山鸢尾、金脉鸢尾和西南鸢尾这四种鸢尾种子存在不同程度的休眠;胚不含萌发抑制剂,已经完成了生理成熟,不是这几种鸢尾休眠的障碍;鸢尾的种皮透水性良好,虽然种皮对萌发有一定的机械抑制作用,然而相对于珠孔端胚乳而言,对胚根伸长的阻力不大,因此不是种子休眠的主要因素。根据实验结果推测,鸢尾种子的胚乳含有萌发抑制剂,然而,珠孔端胚乳的机械束缚可能是鸢尾种子萌发延迟的主要原因。通过进一步的实验发现,玉蝉花和山鸢尾这两种鸢尾胚的生长势高于后两种鸢尾种子,然而,它们的珠孔端结构(胚乳和种皮)对胚伸长的束缚还不及后两者的一半,也就是说,鸢尾种子萌发与否主要取决于珠孔端胚乳对胚根伸长的机械束缚与胚根的生长势的力量的对比,当前者大于后者时,种子不能萌发,当珠孔端胚乳细胞的细胞壁解体或者这一部分被切割之后,珠孔端机械束缚等于或者小于胚的生长势时,种子萌发。

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为了进一步降低水中营养盐浓度、提高水体透明度,为湖泊生态系统的恢复创造条件,促进湖泊水体生态系统良性循环,以太湖五里湖富营养化水体为研究对象,采用中试规模的人工湿地技术来强化净化富营养化水体。重点研究了不同流态、不同基质、不同植物及植物有无条件下各人工湿地系统对富营养化水体的处理效果。此外,还对生长在人工湿地中的7种湿地植物芦苇(Phragmites communis)、香蒲(Typha angustifolia)、茭白(Zizania caduciflora)、水葱(Scirpus validus.)、菖蒲(Acorus calamus)、鸢尾(Iris pseudacorus)和千屈菜(Lythrum salicaria)的生长、生理生态特性如气体交换、叶绿素荧光、光合色素含量及氮、磷吸收能力进行了研究,旨在探索高等植物在富营养化水体净化过程中的机理和规律,为人工湿地污水净化机理奠定一定的科学和理论基础。主要研究结果如下: 通过对垂直潜流、水平潜流和自由表面流三种类型的人工湿地系统对富营养化水体净化效果的对比研究,我们发现在水力负荷0.64 m d-1,进水污染物浓度化学需氧量(COD) 7.37 mg L-1、氨氮(NH4+-N) 1.63 mg L-1、硝氮(NO3--N )1.41 mg L-1、总氮(TN) 4.82 mg L-1和总磷(TP) 0.15 mg L-1的条件下,三种不同流态的人工湿地对富营养化水体均有一定的净化功能。三种类型的人工湿地对主要污染物COD、NH4+-N、NO3--N、TN和TP的去除效果分别为:垂直潜流40.4%、45.9%、62.9%、51.6%和64.3%;水平潜流39.6%、32.0%、65.3%、52.1%和65.7%;自由表面流16.5%、22.8%、34.2%、19.8%和35.1%。相比之下,垂直潜流、水平潜流对主要的污染物的去除效果明显好于自由表面流人工湿地。除垂直潜流湿地NH4+-N的平均去除率显著大于水平潜流外,两人工湿地在其余指标的去除效果上无显著差异。考虑到土地面积的限制,就太湖五里湖富营养化水体治理而言,垂直潜流和水平潜流较自由表面流更为适合。 以沸石为基质的人工湿地较以砾石为基质的人工湿地对NH4+-N有很好的去除效果,除此之外两种基质类型的人工湿地在其余各污染指标的去除效果方面差异不显著。但随着湿地运行时间的延长,沸石对NH4+-N的吸收能力会逐渐减弱,考虑到湿地构建成本,建议就地取材,以当地较为廉价的砾石为人工湿地基质比较经济适用。 有无植物对有机污染物COD的去除效果影响差异不显著,但对TN和TP去除效果影响差异极显著,有植物的人工湿地对TN的去除率比无植物的分别高出12.5%和13.4%,对TP去除率分别高出16.9%和31.0%。不同植物对人工湿地处理效果的影响差异不显著,可见湿地流态对处理效果的影响大于植物的影响。 各湿地植物叶片的净光合速率(Pn)日变化均为双峰曲线,有光合“午休”现象。其中芦苇、茭白、鸢尾、菖蒲、水葱和千屈菜Pn的下降主要是由气孔导度(gs)的下降造成的,而香蒲则更多的受叶肉光合能力下降的影响。除千屈菜的Pn与gs之间呈显著正相关外,其余植物的Pn与gs之间均呈极显著正相关。气孔行为对湿地植物光合作用碳的固定显示了明显的主导控制作用。 各湿地植物的光补偿点(LCP)差异不显著,其均值都在10µmol m-2 s-1以上,显示了阳生植物的特性。但湿地植物的光饱和点 (LSP)差异极显著,LSP大小依次为香蒲1476.3µmol m-2 s-1>水葱1140.0µmol m-2 s-1>菖蒲753.7µmol m-2 s-1>芦苇751.7µmol m-2 s-1>茭白640.7µmol m-2 s-1>千屈菜567.3µmol m-2 s-1>鸢尾479.0µmol m-2 s-1。7种湿地植物的CO2补偿点差异极显著,CO2补偿点大小依次为水葱47.1µmol mol-1>茭白28.4µmol mol-1>香蒲23.7µmol mol-1>鸢尾16.8µmol mol-1>菖蒲16.7µmol mol-1>千屈菜15.2µmol mol-1>芦苇14.8µmol mol-1。与此相反,湿地植物的CO2饱和点差异不显著。 各湿地植物的Fv/Fm值大小差异也极显著,Fv/Fm值大小依次为千屈菜0.8168>水葱0.8348>香蒲0.8262>菖蒲0.8198>芦苇0.8168>茭白0.8040>鸢尾0.7930。由此可见千屈菜、水葱较芦苇和茭白有较高的PSⅡ效率。7种湿地植物叶片的叶绿素a、叶绿素b和类胡萝卜素含量水平差异极显著,芦苇和茭白叶片的叶绿素和类胡萝卜素含量水平都较高,这在客观上解释了他们为何拥有较强的光合能力。 不同湿地植物的生物量大小差异极显著,平均生物量(干重)变化范围在0.26-6.65 kg m-2之间。除香蒲和水葱的地下部生物量显著大于地上部外,其余植物都是地上部生物量大于地下部,这非常有利于人工湿地生态工程中通过收获植物地上部生物量来达到去除氮、磷污染目的。 不同湿地植物植株氮、磷含量差异极显著。湿地植物对氮吸收总量变化范围为6.09-93.96 g m-2,吸收氮最高是芦苇,最低是菖蒲;对磷吸收总量变化范围为0.51-8.95 g m-2,吸收磷最高是香蒲,最低是菖蒲。经测算,植物吸收的总氮量占人工湿地总氮去除量的0.6-17.1%,总磷量占人工湿地总磷去除量的1.4-40.5%。本次试验中香蒲和芦苇对氮、磷的吸收去除能力比较高,茭白、鸢尾、水葱和千屈菜的吸收去除能力中等,而菖蒲的吸收能力较弱。

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三峡库区一些污染严重的工业企业是当地主要的点源污染源,对周围植物群落产生了巨大危害,而植物是生态系统赖以存在的基础,它的生长发育直接影响到生态系统的结构及其正常功能的实现。本研究按照与点源污染源的距离为梯度,通过在三峡库区兴山县白沙河磷化工厂周围布设了32个植物群落固定样地,并以点源污染无法影响到的植物群落为对照,进行样地的野外群落学调查;在每个样地取不同种植物叶片100克左右和样地0~20cm土壤500克,以石灰滤纸法同步进行大气氟化物的取样。样品带回室内应用氟离子选择电极法,测定大气氟化物含量、植物叶片氟的累积量和土壤水溶性氟的含量。同时在野外调查时使用PAM2100叶绿素荧光仪测定植物最大光化学效率即Fv/Fm的值。通过野外调查试验和相关的室内分析,研究了(1):点源污染对三峡库区陆生植物群落组成和物种多样性的影响;(2):点源污染中的主要污染物对植物及土壤环境的影响;(3):不同物种叶片最大光化学效率Fv/Fm对污染胁迫响应的差异。结果如下: 点源污染对植物群落物种丰富度以及Pielou均匀度指数均有不同程度的影响,对于群落结构相对简单的马尾松林和柏木林的不利影响更为显著。相对于污染区来说,对照区中物种重要值的集中程度有所下降。许多物种的重要值在污染区与对照区有明显的变化。马尾松(Pinus massoniana)、檵木(Loropetalum chinense )、铁仔(Myrsine africana)、卷柏(Selaginella tamariscina )等对照区重要值较污染区为高,黄檀(Dalbergia hupeana )、菱叶海桐(Pittosporum truncatum)、君迁子(Diospyros lotus)等污染区的重要值较对照区为高。群落中有些物种比如柏木(Cupressus funebris)的天然更新也受到污染的影响。 污染区土壤pH值大多低于对照区,但是与离污染源距离的相关性不强。污染区有些物种比如马尾松、柏木等叶片中的全氟含量与大气中氟化物的含量和土壤水溶性氟含量明显正相关。但是另外有些物种氟的累积量受点源污染的影响不显著,比如菱叶海桐、翅柃(Eurya alata)等在污染严重的样地内生存状况仍然很好。 在距离点源污染近的样地内,大多数物种的最大光化学效率Fv/Fm的值显著下降。栓皮栎(Quercus variabilis)、马尾松和柏木等的Fv/Fm值与距污染源的距离呈明显的正相关,都是随着离污染源越来越近而逐渐降低。根据污染区相对对照区Fv/Fm值下降幅度的不同,把植物划分为三种类型:对污染敏感型如柏木、铁仔、檵木等,中等敏感型如油桐(Vernicia fordii)、香叶树(Lindera communis)和不敏感型如山胡椒(Lindera glauca)和 蝴蝶花(Iris japonica)等。

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More than 10 species within the freshwater fish genus Sinoncyclocbeilus adapt to caves and show different degrees of degeneration of eyes and pigmentation. Therefore, this genus can be useful for studying evolutionary developmental mechanisms, role of natural selection and adaptation in cave animals. To better understand these processes, it is indispensable to have background knowledge about phylogenetic relationships of surface and cave species within this genus. To investigate phylogenetic relationships among species within this genus, we determined nucleotide sequences of complete mitochondrial cytochrome b gene (1140 bp) and partial ND4 gene (1032 bp) of 31 recognized ingroup species and one outgroup species Barbodes laticeps. Phylogenetic trees were reconstructed using maximum parsimony. Bayesian, and maximum likelihood analyses. Our phylogenetic results showed that all species except for two surface species S. jii and S. macrolepis clustered as five major monophyletic clades (I, II, III, IV, and V) with strong supports. S. jii was the most basal species in all analyses, but the position of S. macrolepis was not resolved. The cave species were polyphyletic and occurred in these five major clades. Our results indicate that adaptation to cave environments has occurred multiple times during the evolutionary history of Sinocyclocheilus. The branching orders among the clades I, II, III, and IV were not resolved, and this might be due to early rapid radiation in Sinocyclocheilus. All species distributed in Yunnan except for S. rhinocerous and S. hyalinus formed a strongly supported monophyletic group (clade V), probably reflecting their common origins. This result suggested that the diversification of Sinocyclocheilus in Yunnan may correlate with the uplifting of Yunnan Plateau. © 2005 Published by Elsevier Inc.