992 resultados para H 800 R425r


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Staphylococcus aureus resistente à meticilina (MRSA) é um importante patógeno pulmonar em pacientes com fibrose cística (FC). Caracteriza-se pela resistência a todos os β-lactâmicos, devido a presença do elemento genético móvel SCCmec o qual abriga o gene mecA. Além disso, é reconhecido por vários fatores de virulência o qual destacamos a toxina Panton-Valentine Leukocidin (PVL), uma citolisina formadora de poros na célula hospedeira, e por apresentar diversos clones epidêmicos envolvidos em surtos hospitalares. O objetivo desse estudo foi caracterizar a epidemiologia de MRSA, isolados de pacientes com FC referente a dois centros de referência no Rio de Janeiro a partir da aplicação de técnicas fenotípicas e genotípicas. Um total de 57 amostras de MRSA foi submetido ao teste de difusão em ágar para 11 antimicrobianos a fim de avaliar perfil de resistência, com aplicação da técnica da PCR foi tipificado o SCCmec e investigado a presença do gene LukS-PV responsável pela codificação da toxina PVL com intuito de estabelecer uma melhor caracterização epidemiológica dos clones identificados pela técnica do MLST (Multilocus Sequence Typing). Os antimicrobianos não β-lactâmicos apresentaram um percentual de resistência abaixo de 50%, em que destacamos a eritromicina com o maior percentual 45,6% e quanto ao perfil de resistência 24,6% foram multirresistentes. Com exceção do SCCmec II, os outros tipos foram encontrados (I, III, IV e V) com os respectivos percentuais de 22,8% (n=13), 7,1% (n=4), 61,4% (n=35) e 3,5% (n=2) e apenas 5,3% (n=3) das amostras não foram caracterizadas, não há dados da prevalência do SCCmec IV. Vinte (35,1%) amostras apresentaram produtos de amplificação compatível com a presença do gene lukS, aproximadamente metade dessas amostras (55%) estava correlacionada ao SCCmec IV. Com a análise do MLST, obtivemos os STs 1 (n=1, 1,7%), 5 (n=28, 49,1%), 30 (n=11, 19,3%), 72 (n=1, 1,7%), 398 (n=1, 1,7%), 1635 (n=7, 12,3%), 1661 (n=2, 3,5%), 239 (n=5, 8,8%), e ainda identificamos um novo ST (2732) presente em 1 amostra. A partir de uma análise associativa entre o MLST e o SCCmec foi possível observar a presença de linhagens características de clones epidêmicos, como o UK-EMRSA-3 (ST5, SCCmec I), USA 800/pediátrico (ST5, SCCmec IV), Oceania Southwest Pacific Clone - OSPC (ST30, SCCmec IV) e Brazilian Epidemic Clone - BEC (ST239, SCCmec III). Em conclusão este estudo é o primeiro a caracterizar linhagens epidêmicas de MRSA nos centros de atendimento a pacientes com FC no Rio de Janeiro, sendo necessário um monitoramento constante a fim de evitar a disseminação desses clones.

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Amostras foram preparadas pelo método de difusão a partir dos reagentes químicos SrCO3, Al2O3 e NiO em proporções estequiométricas. Medidas por difração de raios X mostraram que as amostras possuem uma única fase: SrAl2O4. Neste trabalho apresentamos imagens de microscopia eletrônica de varredura das amostras SrAl2O4 dopadas com 0,1%, 0,5%, 1,0%, 2,0%, 5,0% e 10,0% de íons de Ni2+, medidas de fotoluminescência, excitação da fotoluminescência da amostra SrAl2O4 dopada com 1,0% de íons de Ni2+, medidas de absorção fotoacústica das amostras SrAl2O4 dopadas com 1,0%, 2,0%, 5,0% e 10,0% de íons de Ni2+. Estas medidas foram realizadas a temperatura ambiente para investigar as transições eletrônicas dos íons divalente de níquel que entraram substitucionalmente nos sítios de Sr2+ da rede do SrAl2O4. Os resultados ópticos mostram a existência de três centros emissores de Ni2+. De acordo com a literatura, a estrutura do SrAl2O4 é composta de dois sítios octaédrico distintos de íons de Sr2+, o Sr12+ e o Sr22+, cujas distâncias médias Sr1 O e Sr2 O são, respectivamente, 2,800 Ǻ e 2,744 Ǻ. Visto que os íons de Ni2+ tendem a substituir os íons de Sr2+, devido ao fato de possuírem a mesma valência, é necessário considerar que uma parte dos íons de Ni2+ ocuparam os sítios dos íons de Al3+ na rede do SrAl2O4 para justificar a existência de um terceiro centro emissor de Ni2+ nesse composto. Uma novo sítio octaédrico para os íons de Ni2+ foi estimado a partir do valor da aresta do sítio tetraédrico ocupado pelos íons de Al3+ na rede do SrAl2O4 (considerando o raio iônico do Ni2+ como aproximadamente 40% maior do que o raio iônico do Al3+). As transições eletrônicas presentes nos espectros de excitação e absorção fotoacústica permitiram determinar os parâmetros de campo cristalino (Dq) e Racah (B e C) para os três sítios diferentes ocupados pelos íons de Ni2+ no SrAl2O4. Neste caso, os resultados mostraram que o sítio II dos íons de Ni2+ é associado à posição do Sr1 e possuem um parâmetro Dq menor e que o parâmetro Dq associado aos íons de Ni2+ que substituíram os íons de Sr no sitio I, o qual, por sua vez é associado à posição do Sr2. E, por fim, o sítio III que possui o menor parâmetro de campo cristalino Dq, portanto a maior distância íon ligante, é identificado como aquele relacionado ao rearranjo octaédrico local das antigas posições de Al3+. O caráter higroscópico do SrAl2O4:Ni2+ é observado a partir dos espectros de absorção fotoacústica e os modos de vibração de estiramento das ligações Ni OH e O H são identificadas nos espectros.

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Nos últimos anos, duas espécies de lagostas sapateiras, Scyllarides brasiliensis e S. deceptor, vêm se destacando nos desembarques pesqueiros de lagostas do Atlântico Sul Ocidental. Para espécies comercialmente importantes, o desenvolvimento de estudos que permitam conhecer a variabilidade e entender a dinâmica populacional é fundamental. Assim, o objetivo do primeiro capítulo desta tese foi avaliar a diversidade genética e a estrutura populacional dessas duas lagostas ao longo de aprox. 2.800 km da costa da América do Sul. Para as análises, foram empregados marcadores mitocondriais (citocromo oxidase I: COI; e a região controle: RC) e marcadores nucleares (13 loci de microssatélites desenvolvidos nesta tese). As duas espécies apresentaram altos níveis de variabilidade (S. deceptor: N = 200, mtDNA: h > 0,841, π > 0,005; microssatélites: He = 0,685; S. brasiliensis: N = 211, He = 0,554), distribuídos homogeneamente entre as localidades (S. deceptor: ΦST < -0,004, ΦCT < 0,016, FST global = 0,001, Dest global = 0,003, FCT < 0,002, P > 0,05, K = 1; S. brasiliensis: FST global = 0,004, Dest global = 0,001, FCT < 0,004, P > 0,05, K = 1). A ausência de estruturação nas duas espécies pode estar relacionada a características biológicas que promovem a conectividade entre localidades geograficamente distantes, como alta fecundidade e alto potencial de dispersão das larvas planctônicas. Além disso, os dados mitocondriais sugerem que a história demográfica de S. deceptor foi marcada por eventos de expansão populacionais e geográficos possivelmente relacionados às condições ambientais favoráveis dos episódios interglaciais do Pleistoceno Médio-Tardio. Diversos estudos têm mostrado que os fenômenos de inserção de regiões mitocondriais no DNA nuclear (NuMts) e heteroplasmia limitam a correta amplificação e identificação dos marcadores mitocondriais. Em estudos filogenéticos e de genética de populações, a presença inadvertida de sequências de diversas origens viola o principio de ortologia, o que pode resultar em inferências evolutivas erradas. Assim, o objetivo do segundo capítulo desta tese foi identificar e caracterizar os possíveis NuMts e sequências heteroplásmicas de três regiões mitocondriais (COI, RC e o gene da subunidade maior do RNA ribossomal: 16S) em quatro espécies do gênero Scyllarides (S. aequinoctialis, S. brasiliensis, S. deceptor e S. delfosi). A clonagem e sequenciamento de extratos de DNA genômico e DNA enriquecido com mtDNA revelaram que os genomas destas espécies podem exibir NuMts (que divergem entre 0,6 e 17,6% do mtDNA) e heteroplasmia (que divergem < 0,2% do mtDNA prevalente). Os NuMts surgiram possivelmente de vários eventos independentes de integração ao núcleo ao longo da história evolutiva do gênero Scyllarides. Dependendo do seu grau de similaridade com o mtDNA, a presença de NuMts nas análises filogenéticas no nível de gênero pode causar superestimativa do número de espécies e alterações nos comprimentos dos ramos e nas relações filogenéticas entre espécies.

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In 2001, representative samples of adult Columbia Basin chinook (Oncorhynchus tshawytscha), sockeye (O. nerka), and coho salmon (O. kisutch) populations at Bonneville Dam were collected. Fish were trapped, anesthetized, sampled for scales and biological data, revived, and then released adult migrating salmonids. Scales were examined to estimate age composition; the results contributed to an ongoing database for age class structure of Columbia Basin salmon populations. Based on scale analysis of chinook salmon, four-year-old fish (from brood year [BY] 1997) comprised 88% of the spring chinook, 67% of the summer chinook, and 42% of the Bright fall chinook salmon population. Five-year-old fish (BY 1996) comprised 9% of the spring chinook, 14% of the summer chinook, and 9% of the fall chinook salmon population. The sockeye salmon population at Bonneville was predominantly four-year-old fish (81%), with 18% returning as five-year-olds in 2001. The coho salmon population was 96% three-year-old fish (Age 1.1). Length analysis of the 2001 returns indicated that chinook salmon with a stream-type life history are larger (mean length) than the chinook salmon with an ocean-type life history. Trends in mean length over the sampling period for returning 2001 chinook salmon were analyzed. Chinook salmon of age classes 0.2 and 1.3 show a significant increase in mean length over time. Age classes 0.1, 0.3, 0.4, 1.1, 1.2, and 1.4 show no significant change over time. A year class regression over the past 12 years of data was used to predict spring, summer, and Bright fall chinook salmon population sizes for 2002. Based on three-year-old returns, the relationship predicts four-year-old returns of 132,600 (± 46,300, 90% predictive interval [PI]) spring chinook and 44,200 (± 11,700, 90% PI) summer chinook salmon for the 2002 runs. Based on four-year-old returns, the relationship predicts five-year-old returns of 87,800 (± 54,500, 90% PI) spring, 33,500 (± 11,500, 90% PI) summer, and 77,100 (± 25,800, 90% PI) Bright fall chinook salmon for the 2002 runs. The 2002 run size predictions should be used with caution; some of these predictions are well beyond the range of previously observed data.

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In 2000, representative samples of adult Columbia Basin chinook (Oncorhynchus tshawytscha), sockeye (O. nerka), and coho salmon (O. kisutch), populations were collected at Bonneville Dam. Fish were trapped, anesthetized, sampled for scales and biological data, allowed to revive, and then released. Scales were examined to estimate age composition and the results contribute to an ongoing database for age class structure of Columbia Basin salmon populations. Based on scale analysis, four-year-old fish (from brood year (BY) 1996) were estimated to comprise 83% of the spring chinook, 31% of the summer chinook, and 32% of the upriver bright fall chinook salmon population. Five-year-old fish (BY 1995) were estimated to comprise 2% of the spring chinook, 26% of the summer chinook, and 40% of the fall chinook salmon population. Three-year-old fish (BY 1997) were estimated to comprise 14% of the spring chinook, 42% of the summer chinook, and 17% of the fall chinook salmon population. Two-year-olds accounted for approximately 11% of the fall chinook population. The sockeye salmon population sampled at Bonneville was predominantly four-year-old fish (95%), and the coho salmon population was 99.9% three-year-old fish (Age 1.1). Length analysis of the 2000 returns indicated that chinook salmon with a stream-type life history are larger (mean length) than the chinook salmon with an ocean-type life history. Trends in mean length over the sampling period were also analysis for returning 2000 chinook salmon. Fish of age classes 0.2, 1.1, 1.2, and 1.3 have a significant increase in mean length over time. Age classes 0.3 and 0.4 have no significant change over time and age 0.1 chinook salmon had a significant decrease in mean length over time. A year class regression over the past 11 years of data was used to predict spring and summer chinook salmon population sizes for 2001. Based on three-year-old returns, the relationship predicts four-year-old returns of 325,000 (± 111,600, 90% Predictive Interval [PI]) spring chinook and 27,800 (± 29,750, 90% PI) summer chinook salmon. Based on four-year-old returns, the relationship predicts five-year-old returns of 54,300 (± 40,600, 90% PI) spring chinook and 11,000 (± 3,250, 90% PI) summer chinook salmon. The 2001 run size predictions used in this report should be used with caution, these predictions are well beyond the range of previously observed data.

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In 2002, representative samples of migrating Columbia Basin chinook (Oncorhynchus tshawytscha), sockeye (O. nerka), and coho salmon (O. kisutch) adult populations were collected at Bonneville Dam. Fish were trapped, anesthetized, sampled for scales and biological data, revived, and then released. Scales were examined to estimate age composition; the results contributed to an ongoing database for age class structure of Columbia Basin salmon populations. Based on scale analysis of chinook salmon, four-year-old fish (from brood year [BY] 1998) comprised 86% of the spring chinook, 51% of the summer chinook, and 51% of the bright fall chinook salmon population. Five-year-old fish (BY 1997) comprised 13% of the spring chinook, 43% of the summer chinook, and 11% of the bright fall chinook salmon population. The sockeye salmon population at Bonneville was predominantly five-year-old fish (55%), with 40% returning as four-year-olds in 2002. For the coho salmon population, 88% of the population was three-year-old fish of age class 1.1, while 12% were age class 1.0. Length analysis of the 2002 returns indicated that chinook salmon with a stream-type life history are larger (mean length) at age than the chinook salmon with an ocean-type life history. Trends in mean length over the sampling period for returning 2002 chinook salmon were analyzed. Chinook salmon of age classes 1.2 and 1.3 show a significant increase in mean length over the duration of the migration. A year class regression over the past 14 years of data was used to predict spring, summer, and bright fall chinook salmon population sizes for 2003. Based on three-year-old returns, the relationship predicts four-year-old returns of 54,200 (± 66,600, 90% predictive interval [PI]) spring chinook, 23,800 (± 19,100, 90% PI) summer, and 169,100 (± 139,500, 90% PI) bright fall chinook salmon for the 2003 runs. Based on four-year-old returns, the relationship predicts five-year-old returns of 36,300 (± 35,400, 90% PI) spring, 63,800 (± 10,300, 90% PI) summer, and 91,100 (± 69,400, 90% PI) bright fall chinook salmon for the 2003 runs. The 2003 run size predictions should be used with caution; some of these predictions are well beyond the range of previously observed data.

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葡萄属(Vitis.L.)植物隶属于葡萄科(Vitaceae),主要分布于北温带,最南可以分布到南美洲的委内瑞拉和亚洲的越南以及印度北部。本文通过对该属分类研究历史的回顾,认为该属存在的问题主要表现在如下几个方面: 1)葡萄属自1753 年由Carl Linne创立以来,虽经planchon于1887年做了修订,但属的范围仍需进一步界定;2)在Planchon之后的100多年中未见有一全面的分类学修订工作,出现在该属的800多个名称需要考证;3)对一些广布种的变异认识不足,导致了大量可疑种。针对这些问题本文进行了如下几个方面的工作: l、形态学:通过大量的野外工作和标本观察,对该属植物的主要性状做了分析,讨论了这些性状状态在葡萄属中的变异规律及演化趋势,将灌木状习性、退化的卷须以及不裂的叶片视为进化的性状。 2、细胞学:利用前人对葡萄属(Vitis.L.)染色体数目的统计及一些杂交实验分析的结果,结合形态学等方面的特征分析,认为在葡萄科,染色体基数X=10为原始的,而x=19则为衍生的。葡萄属的染色体基数xl9(2n=38),多倍体较少见;麝香葡萄属[Muscadinia (Planch.) Sma11]的染色体基数为x=10 (2n=20).与蛇葡萄属、酸蔹藤属和爬山虎属的一致。葡萄属和麝香葡萄属间的杂种是不育的。 3、孢粉学:对葡萄属32种5变种及麝香葡萄属[Muscadinia (Planch.) Sma11]1种的花粉外壁做扫描电镜观察,结果发现花粉外壁雕纹在这两属间和葡萄属内变异较小,对区分属以及属下种上类群意义不大,但对种的鉴别有重要的价值。 4、植物化学:前人对植物化学的工作表明,植物的一些次生代谢产物如类黄酮化合物在葡萄科各类群中的分布规律较好地反映了各类群间的关系。这些结果较好地支持了Planchon对葡萄属范围的界定。 5、山葡萄复合体(V.amurensis complex)包括山葡萄(V.amurensis Rupr.)、燕山葡萄(V.amuresis Rupr. var. dissecta Skvorts.=var.yanshanensisD.Z.Lu et H.P.Liang)、百花山葡萄(V.baihuashanensis M.S.Kang et D.Z.Lu)、复叶葡萄(V.piasezkii Maxim.)、少毛复叶葡萄[V. piasezkii Maxux1.var. pagnuccii (Planch.) Rehd.]共3个种和2个变种,广泛分布于中国北方,形态变异较大。本文对该复合体做了形态分析,并用RAPD (Random Amplified Polymorphic DNAs)分子标记方法分析了这几个类群的关系。综合这些结果,归并了燕山葡萄和百花山葡萄。 在上述工作的基础上,我们得出了如下的结论: l、葡萄属在葡萄科中是一个进化的类群。整理后的葡萄属包括8系62种、l亚种和15变种,其中有2个新系、1个新组合系、2个新变种、1个新组合种和l3个新异名。 2、本文赞同SmaU在1903年作出的分类学处理,把麝香葡萄作为一个独立的属,比葡萄属原始但与葡萄属有着最近的亲缘关系。 3、依据形态特征和APD分析结果把山葡萄复合体的3个种2变种归并为2种l变种,即山葡萄、复叶葡萄和少毛复叶葡萄,认为分子标记技术在分析属内近缘种闻关系上很有价值。 4、葡萄属具有东亚和北美2个现代分布中心,该属可能起源于北美的东部,在晚白垩纪经白令陆桥散布至欧亚大陆。

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Siloxane Polymer exhibits low loss in the 800-1500 nm range which varies between 0.01 and 0.66 dB cm1. It is for such low loss the material is one of the most promising candidates in the application of engineering passive and active optical devices [1, 2]. However, current polymer fabrication techniques do not provide a methodology which allows high structurally solubility of Er3+ ions in siloxane matrix. To address this problem, Yang et al.[3] demonstrated a channel waveguide amplifier with Nd 3+-complex doped polymer, whilst Wong and co-workers[4] employed Yb3+ and Er3+ co-doped polymer hosts for increasing the gain. In some recent research we demonstrated pulsed laser deposition of Er-doped tellurite glass thin films on siloxane polymer coated silica substrates[5]. Here an alternative methodology for multilayer polymer-glass composite thin films using Er3+ - Yb3+ co-doped phosphate modified tellurite (PT) glass and siloxane polymer is proposed by adopting combinatorial pulsed laser deposition (PLD). © 2011 IEEE.

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Tubular graphite cones (TGCs) with a single-crystal nanotip have been achieved by means of microwave plasma-assisted chemical vapor deposition using in-situ-evaporated Fe catalysts. The absence of the disorder-induced D band in Raman spectra revealed the single-crystalline feature of the nanotip. TGCs were found to stem from Fe catalytic carbon spherules on the order of 100 mum diameter, whose critical role in promoting both nucleation and plasma annealing in the formation of highly crystalline TGCs is discussed. The crystalline quality of such TGCs can be further verified by the investigation of their oxidative stability in air. All TGCs can survive up to 600 degrees C without any structural variations, and a few TGCs still survive with an anisotropic etched and stepped nanotip at temperatures up to 800 degrees C, much better than CNTs. Thus, TGCs with single crystalline nanotips are potential candidates for scanning probes in high-temperature oxygen-containing environments.

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PURPOSE: Stabilisation/solidification (S/S) has emerged as an efficient and cost-effective technology for the treatment of contaminated soils. However, the performance of S/S-treated soils is governed by several intercorrelated variables, which complicates the optimisation of the treatment process design. Therefore, it is desirable to develop process envelopes, which define the range of operating variables that result in acceptable performance. METHODS: In this work, process envelopes were developed for S/S treatment of contaminated soil with a blend of hydrated lime (hlime) and ground granulated blast furnace slag (GGBS) as the binder (hlime/GGBS = 1:4). A sand contaminated with a mixture of heavy metals and petroleum hydrocarbons was treated with 5%, 10% and 20% binder dosages, at different water contents. The effectiveness of the treatment was assessed using unconfined compressive strength (UCS), permeability, acid neutralisation capacity and contaminant leachability with pH, at set periods. RESULTS: The UCS values obtained after 28 days of treatment were up to ∼800 kPa, which is quite low, and permeability was ∼10(-8) m/s, which is higher than might be required. However, these values might be acceptable in some scenarios. The binder significantly reduced the leachability of cadmium and nickel. With the 20% dosage, both metals met the waste acceptance criteria for inert waste landfill and relevant environmental quality standards. CONCLUSIONS: The results show that greater than 20% dosage would be required to achieve a balance of acceptable mechanical and leaching properties. Overall, the process envelopes for different performance criteria depend on the end-use of the treated material.

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植物细胞壁富含羟脯氨酸糖蛋白生化特性及基因克隆的研究分成三部分: 第一部分,首先从胡萝卜愈伤组织的细胞壁中获得0.2M氯气钙可溶性蛋白质组分, 经10% TCA沉淀及羧甲基纤维素层析,分离得到一个伸展蛋白,并以SDS-聚丙烯酰胺凝胶电泳,氨基酸组成分析,分子电镜观察对所得的伸展蛋白进行了鉴定,结果表明,在胡萝卜愈伤组织中只存在一种伸展蛋白;SDS-聚丙烯酰胺凝胶电泳的考马斯蓝染色和PAS反应均为阳性,表明伸展蛋白除蛋白质组分还含有糖基;氨基酸组成分析表明,羟脯氨酸的克分子含量约占全部氨基酸的40%,丝氨酸的克分子含量约为羟脯氨酸的四分之一,含有大量的碱性和中性氨基酸,而只含有非常少量的酸性氨基酸,并且这些氨基酸克分子百分数也接近于胡萝卜富含羟脯氨酸糖蚤白基因推测出的克分子百分数。这些结果表明已经得到了一个电泳纯的伸展蛋白。伸展蛋白分子电镜观察证明它是一个棒状分子,长度为87纳米。 第二部分,用得到的伸展蛋白免疫家兔和大鼠,得到的抗体的免疫双扩散效价分别为1:2和1:1,用酶联免疫吸附分析测定的兔抗体效价为1:12,800,同时还建立了竞争性酶联免疫吸附分析测定伸展蛋白含量的标准曲线,线性范围为10-0.00001微克。利用得到的抗体对大豆下胚轴伸展蛋白的合成进行了研究。免疫荧光定位表明,大豆下胚轴表皮细胞及表皮下几层薄壁细胞有大量的荧光标记,并且这些荧光标记大部分分布在细胞质内。大豆下胚轴O.lM Tris-HCl pH7.4和0.2M氯化钙的提取物Western Blotting分析证明0.2M氯化钙提取物有与胡萝卜伸展蛋白电流性质相似的组分,并且这个组分在真菌诱导物处理的大豆下胚轴中的积累明显高于受伤处理的下胚轴。受伤和真菌诱导物处理大豆下胚轴中伸展蛋白积累的变化已经用Western Blotting分析和斑点酶联免疫吸附分析来观察,发现真菌诱导物处理的对灰斑病抗性的大豆下胚轴能够较快地积累伸展蛋白(24 - 48小时),而敏感品系的大豆下胚轴则合成伸展蛋白较晚(43-72小时)。在观察大豆下胚轴免疫荧光定位也发现类似的结果。对伸展蛋白基因的转录活性的初步研究认为抗性品系的大豆下胚轴同源mRNA转录可能早于24小时,而敏感品系大豆下胚轴同源mRNA转录可能在24小时后。以上结果认为大豆下胚轴含同源的mRNA和蛋白质组分,因此推测大豆基因组DNA有伸展蛋白基因。 第三部分,根据第二部分得到的结果,用已经得到的编码胡萝卜伸展蛋白的基因(克隆于pUC8质粒载体中)作探针,与大豆基因组DNA的EcoRI部分酶解片段杂交寻找大豆伸展蛋白基因,已经发现四个片段与探针DNA有同源性。它们的分子量分别约为23kb,8kb,5kb和2.8kb,并且23kb片段可能有更高的同源性。将23kb片段插入pUC9质粒载体上进行可隆,并用菌落原位杂交筛选获得5个克隆,对其中两个克隆用ECoRI酶解并进行分子杂交分析,重组质粒被EcoRI切成四个片段。2.8kb片段为pUC9栽体,2kb片段为与pDC5AI质粒伸展蛋白同源性较好的片段。对于23kb片段的重组质粒有待于进一步的分析。

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Detection and perception of ecological relationships between biota and their surrounding habitats is sensitive to analysis scale and resolution of habitat data. We measured strength of univariate linear correlations between reef fish and seascape variables at multiple spatial scales (25 to 800 m). Correlation strength was used to identify the scale that best associates fish to their surrounding habitat. To evaluate the influence of map resolution, seascape variables were calculated based on 4 separate benthic maps produced using 2 levels of spatial and thematic resolution, respectively. Individual seascape variables explained only 25% of the variability in fish distributions. Length of reef edge was correlated with more aspects of the fish assemblage than other features. Area of seagrass and bare sand correlated with distribution of many fish, not just obligate users. No fish variables correlated with habitat diversity. Individual fish species achieved a wider range of correlations than mobility guilds or the entire fish assemblage. Scales of peak correlation were the same for juveniles and adults in a majority of comparisons. Highly mobile species exhibited broader scales of peak correlation than either resident or moderately mobile fish. Use of different input maps changed perception of the strength and even the scale of peak correlations for many comparisons involving hard bottom edge length and area of sand, whereas results were consistent regardless of map type for comparisons involving area of seagrass and habitat diversity.

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本文采用树脂复型法对裸子植物红豆杉的管胞,木本单子叶植物竹和棕榈藤木质部中各种管状分子(主要是导管和管胞)的内壁结构进行了研究;采用原子力显微镜对玉米和小麦根内皮层细胞内切向壁的表面结构进行了探索性的研究;用光学显微镜并结合荧光技术对典型的旱生、中生及水生植物根内皮层的次生加厚壁进行了比较观察;同时辅以传统的组织切片法对以上研究结果做了进一步的论证。 采用树脂复型法,不仅可观察到常规解剖法所能展示的结构,而且还可清晰地观察到管状分子间具缘纹孔对等常规方法所难以显示的三维构造,并对其各项结构参数进行了定量测量。结果表明:裸子植物管胞和竹、藤管状分子具缘纹孔的内、外口比例分别约为3:1 和1:1,其它各项结构参数均存在较大差别。此外,在云南省藤和桂竹等导管内壁上还观察到瘤层结构,瘤体直径大小为200-800纳米之间。 旱生植物内皮层细胞内切向壁的闪生加厚最为明显,水生植物的加厚程度最微弱,而中生植物则介于两类植物之间。玉米内皮层细胞内切向壁的内表面起伏不平,并具有70-90纳米的“孔状”质外体结构,其频率约为2,000个/平方微米。