189 resultados para Açaí-de-touceira


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本研究利用皱纹盘鲍的EST序列进行单核苷酸多态(SNP)标记开发;对等位基因特异性PCR(AS-PCR)方法进行了优化,使之适合SNP基因型分析;对一个作图家系开发基因相关SNP标记,并对标记在子代个体中的分离情况进行了分析,探讨了借助SNP在遗传连锁图谱上定位功能基因的方法。 对大约5800条EST序列进行拼接,共获得含有4条以上序列的contig 150个,在86个含有单碱基突变位点的contigs中发现SNP 302个,碱基置换类型A/G(C/T)、A/C(G/T)、A/T、C/G的位点数目分别为147、90、21、16个。50个contigs在BLASTx分析后具有匹配(E值小于1E-5),其中的220个SNPs全部为同义cSNPs,位于遗传密码子的第三简并位。粗略估算,皱纹盘鲍核基因组中SNP的平均分布密度不低于1%。 通过扩增DNA pool后产物直接测序共验证了28个SNP。PCR直接测序法操作简单,结果可靠,一次测序可能验证多个位点,有时还可以发现新的突变位点。通过重点研究引物3’端不同错配对PCR扩增的影响,对AS-PCR的引物设计原则及反应条件进行了探讨及优化,发现在AS引物的3’端倒数第二位引入额外的强错配后,AS-PCR检测SNP的特异性会得到很大的提高,从而使AS-PCR可以满足小规模的SNP基因型分析。 根据EST-contig或者单一的EST序列设计PCR引物74组,其中43组可以特异扩增皱纹盘鲍基因组DNA。用这些引物扩增一个作图家系的父母本,并对PCR产物纯化后分别进行双向直接测序,在18个基因片段中发现了86个SNP,其中82个是新SNP,并且绝大多数SNP位于内含子序列中。这些SNP在父母本中的基因型,在多数情形下,是一方为纯合(AA),而另一方为杂合(AB);父母本均为杂合和均为纯合的形式则较少。在父母本中杂合形式的SNP位点,理论上可以在子代中发生分离。 在每个基因的内含子中选择父母本基因型为AA×AB或者AB×AA的SNP位点,设计AS-PCR分型引物并检测123个子代个体的基因型。在对9个基因中的11个SNP位点(包括5个母本标记和6个父本标记)进行子代基因型分析后发现,2个位点不符合孟德尔1:1分离(P < 0.05),符合预期分离比率的9个位点存在较大可能定位于遗传连锁图谱。通过分析两组父母本标记(F142和M142,F459和M459)发现,在根据父母本序列设计SNP分型引物时,可以设计指向同一基因的成对的父母本标记,从而使两个单亲标记可作为一个共同标记使用。

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The fatty acids composition in different parts of full-grown Rhopilema esculentum jellyfish from Yellow Sea was investigated. The lipids, extracted from the umbrella and oral arms and gonads of R. eculentum jellyfish, respectively were analysed by combined capillary gas chromatography/mass spectrometry. The results show that there are more than thirty kinds of fatty acids in jellyfish, and the fatty acid compositions of three parts of R. esculentum are almost the same. In the three parts, percentages of polyunsaturated fatty acids (PUFA) are high, and range from 36.23% to 38.74%. Docosahexaenoic acid (DHA), eicosatetraenoic acid (AA) and eicosapentaenoic acid (EPA) are three major PUFA.

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An LC method for the determination of 20 amino acids (AAs), using 1,2-Benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC) as fluorescent labeling reagent, has been validated and applied for the analysis of AAs in rat plasma at three different states concerning exercise physiology. Identification of AA derivatives was carried out by LC-MS with electrospray ion (ESI), and the MS-MS cleavage mode of the representative tyrosine (Tyr) derivative was analyzed. Gradient elution on a Hypersil BDS C-18 column gave good separation of the derivatives. Excellent linear responses were observed and good compositional data could be obtained from as little as 50-200 mu L of plasma samples. The contents of 20 AAs in rat plasma of three groups (24 rats, group A: quiet state, group B: at exercising exhaust, group C: 12 h after exercising exhaust) exhibited evident difference corresponding to the physiological states. Facile BCEOC derivatization coupled with LC-FLD-ESI-MS analysis allowed the development of a highly sensitive method for the quantitative analysis of trace level of AAs from plasma or other biochemical samples.

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Kinesins are common in a variety of eukaryotic cells with diverse functions. A cDNA encoding a member of the Kinesin-14B subfamily is obtained using X-RACE technology and named AtKP1 (for Arabidopsis kinesin protein 1). This cDNA has a maximum open reading frame of 3.3 kb encoding a polypeptide of 1087 aa. Protein domain analysis shows that AtKP1 contains the motor domain and the calponin homology domain in the central and amino-terminal regions, respectively. The carboxyl-terminal region with 202 aa residues is diverse from other known kinesins. Northern blot analysis shows that AtKP1 is widely expressed at a higher level in seedlings than in mature plants. 2808 bp of the AtKP1 promoter region is cloned and fused to GUS. GUS expression driven by the AtKP1 promoter region shows that AtKP1 is mainly expressed in vasculature of young organs and young leaf trichomes, indicating that AtKP1 may participate in the differentiation or development of Arabidopsis thaliana vascular bundles and trichomes. A truncated AtKP1 protein containing the putative motor domain is expressed in E. coli and affinity-purified. In vitro characterizations indicate that the polypeptide has nucleotide-dependent microtubule-binding ability and microtubule-stimulated ATPase activity.

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A novel actinomycete strain, designated YIM 002(T), was isolated from a desert soil sample in Gansu Province, north-west China. This actinomycete isolate formed well-differentiated aerial and substrate mycelia. In the early stages of growth, the substrate mycelia fragmented into short or elongated rods. Chemotaxonomically, it contained LL-2,6-diaminopimelic acid in the cell wall. The cell-wall sugars contained ribose and glucose. Phospholipids present were phosphatidylinositol mannosides, phosphatidylinositol and diphosphatidylglycerol. MK-9(H-4) was the predominant menaquinone. The major fatty acids were anteiso C-15:0 (35.92%), anteiso C-17:0 (15.84%), iso C-15:0 (10.40%), iso C-16:0 (7.07%) and C(17:10)w8c (9.37%). The G+C content of the DNA was 70 mol%. Phylogenetic analysis and signature nucleotide data based on 16S rRNA gene sequences showed that strain YIM 002(T) is distinct from all recognized genera of the family Nocardioidaceae in the suborder Propionibacterineae. On the basis of the phenotypic and genotypic characteristics, it is proposed that isolate YIM 002(T) be classified as a novel species in a new genus, Jiangella gansuensis gen. nov., sp. nov. The type strain is YIM 002(T) (= DSM 44835(T) = CCTCC AA 204001(T) = KCTC 19044(T)).

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The magnetosphere-ionosphere coupling is mainly manifested by the trans- porting processes of energy into the ionosphere , the energy is carried by solar wind and firstly accumulate at the magnetosphere, and the coupling processes also significantly include the interaction between the magnetosphere and ionosphere for mass and energy. At the quiet condition, energy is delivered by the large-scale convection of the geomagnetic field; the huge energy from solar wind bulk will be injected into and consumed at the near magnetosphere and ionosphere by the geomagnetic storm and substorm activities. Aurorae and FACs (Field-aligned currents) are the important phenomena in the coupling processes. In the present work, firstly, we analyze the activity characteristics of auroral precipitating particle, secondly, we study the distribution characters of large-scale field aligned currents (LS FACs) at storm-time using the observations from different satellites at different altitudes. Finally, we investigate the evolution of the geomagnetic field configuration at the nightside sector on the onset of the expansion phase in a substorm event, the substorm event happened at 0430UT to 0630UT on 8th Nov. 2004. The main results as follows: At the first, the data of the estimated power input (EPI) of auroral particles from NOAA/POES (Polar orbiting environmental satellite) for some 30 years have been analyzed. The variation tendencies of the EPI generally coincide with aa, AE and Dst indices. The annual variation of EPI shows equinox peaks and an asymmetric-activity with a higher peak in the winter-hemisphere than in the summer-hemisphere. The diurnal UT variations are different from north and south hemisphere: for north hemisphere, the peak appears at 1200UT, and the relative deviation is 22% to the daily average of the north hemisphere. For south hemisphere, the maximal deviation is 22% at 2000UT. So the diurnal variation of EPI is more dominant than the annual variation which maximal deviation is 3% to 12% for different seasons. Studies on correlations of the hourly average of EPI, Pa, with AE and Dst indices show a correlation coefficient r=0.74 of Pa and AE, and r=-0.55 of Pa and Dst. The hourly EPIs for north and south polar regions, NPa and SPa, show a north-south asymmetry with a higher correlation of SPa and AE (or Dst). Time delays of EPI with respect to magnetic indices are examined, the maximum correlation coefficient of Pa with AE (r=0.78) occurs when the time delay =0, suggesting a synchronous activity of auroral electrojet and auroral precipitating particles, while =1-2h, the correlation coefficient of Pa with Dst is maximum (r=0.57), suggesting that the activity of auroral particle precipitating may influence the ring current on some extent. Sencondly, we use the high-resolution magnetic field vector data of the CHAMP satellite to investigate the distribution of large-scale FACs during the great magnetic storm on 7th to 8th Nov. 2004. The results show that, whether in the northern or southern hemisphere, the number and density of large-scale FACs during the main-phase are more and bigger than these during the recover-phase, and the number of large-scale FACs in morning sector obviously is more than that in afternoon sector. In terms of the magnetic indices, we find that large-scale FACs in morning sector significantly affected by the substorm activities, while in afternoon sector the large-scale FACs mainly indicate the fluctuations of the ring-current in storm time. Accordingly to the former studies, similarly, we find that in the morning sector, the scale of the large-scale FACs move to the high-latitude region, and in the afternoon sector, large-scale FACs distinctly expand to the low-latitude region. During the time periods that the NOAA/POES auroral precipitating particle power data temporally correspond to the large-scale FACs, the more the power of auroral particle is, the more and bigger the number and density of FACs are. At the same time, we use the magnetic field vector data of POLAR obtain a good form of region 1, region 2, and three pieces of cusp FACs during a single transit at 1930UT-2006UT on 07th. And the characteristics of simultaneous electric field and energy particles observations on Polar are coincide with the five FACs pieces. Finally, by means of the observation of Cluster 4 and Goes 10、 Goes 12, we analyze the evolution process of the change of the magnetic field configuration at night sector at the expansion phase of a substorm event which happened during 0430UT to 0630UT on 8th Nov. 2004, we find that the times of the beginning of the polarizations of magnetic field are observed from Goes 10 to Goes 12 then to Cluster 4. So, at the synchronous orbit ( 6.6 RE) to 10RE distance scale of the neutral sheet, the current disruption spread tailward. Simultaneously, the strengthen of the FACs deduced from these satellites’ magnetic field observations are almost consistent with the times of polarizations, as well as the high energy particles injection and the electric field dominant variation. The onset times determined by the magnetic field polarizations from these satellites are all ahead of the onset time that confirmed from the auroral electrojet indices. So, these characters of different observations can be used as the criterions to determine the onset time for the substorms of such type as we studied.

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全新世气候变化研究是古气候研究的一个重点。中国全新世气候变化的研究也是全球变化研究中重要的一部分。大量的研究工作为恢复中国全新世气候做了重大贡献。中国地形地貌复杂,又处在具有复杂时空变率的东亚季风控制范围内,这使得不同的研究工作者在一些问题上存在意见分歧。比较统一的意见是:中国全新世始于约10. 5ka BP ;在约9~8 ka BP 左右为一段降温期;7~4 ka BP 为一段温暖期,通常称之为全新世大暖期;大约3 kaBP 左右开始降温,至近代才又升温; 约1300 a A. D. 左右进入小冰期,到1850 aA.D. 左右结束,其间又有几次比较明显的温度振荡。1850 a A. D. 至今为温度的上升期。对于气候变动的驱动因素,不同的学者看法不一;从长时间尺度看,太阳辐射变化是气候变化的主要驱动力。

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铊是一种低温元素,可形成富铊矿床。主要呈独立矿物红铊矿、斜硫砷系铊矿、Imhofite等形式存在。在卡林型金矿中Aa-Tl关系密切。流体包裹体、稳定同位素稀土元素地球化学,成矿模拟实验研究表明:富铊矿床的成矿流体主要来自大气降水和地层中的热卤水,成矿物质主要来源于地层,部分可能来自深部。从而建立了富(含)铊矿床形成的三阶段成矿模式。铊的环境地球化学研究表明,富铊矿床的开发利用是导致环境铊污染和地方性锭中毒的原因。

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An immunosorbent was fabricated by encapsulation Of monoclonal anti-isoproturon antibodies in sol-gel matrix. The immunosorbent-based loading, rinsing and eluting processes were optimized. Based on these optimizations, the sol-gel immunosorbent (SG-IS) selectively extracted isoproturon from an artificial mixture of 68 pesticides. In addition to this high selectivity, the SG-IS proved to be reusable. The SG-IS was combined with liquid chromatography-tandem mass spectrometry (LC-MS-MS) to determine isoproturon in surface water, and the linear range was up to 2.2 mu g/l with correlation coefficient higher than 0.99 and relative standard deviation (RSD) lower than 5% (n = 8). The limit of quantitation (LOQ) for 25-ml surface water sample was 5 ng/l. (c) 2006 Elsevier B.V. All rights reserved.