11 resultados para de Sitter relativity

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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We study the Hawking radiation of a (4+n)-dimensional Schwarzschild black hole imbedded in space-time with a positive cosmological constant. The greybody and energy emission rates of scalars, fermions, bosons, and gravitons are calculated in the full range of energy. Valuable information on the dimensions and curvature of space-time is revealed. Furthermore, we investigate the entropy radiated and lost by black holes. We find their ratio near 1 in favor of the Bekenstein's conjecture.

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随机性检测在密码学中发挥着重要的作用,目前,已有多种不同的随机性检测算法.但是,实际应用中选择所有的检测算法进行检测不现实,选择哪些算法能够使检测充分且无冗余,这需要研究检测算法之间可能存在的关系.对两种重要的随机性检测算法二元推导和自相关进行了研究.从二者的基本原理出发,对其检测的推导过程进行了分析,结合杨辉三角的性质证明了在参数k选择为2t时,二元推导与自相关是等价的.若同时进行参数为2t的二元推导检测和自相关检测则存在冗余.同时对这个结论进行了实验验证.另外,研究还发现,在参数k选择为2t-1时,二元推导检测中推导序列的每一个比特包含初始序列的所有相关比特信息.所研究工作为实际应用中随机性检测项目和检测参数的选择提供了理论的指导.

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糯小麦在食品加工业、淀粉加工业及其它工业上有着重要用途,是近年来许多国家小麦研究的重要课题。国外糯小麦选育尚未突破高产与糯性相结合的难点,国内目前还没有培育出高蛋白强筋型的糯小麦品种,这在一定程度上与缺乏合适的育种方法和高效、实用的糯小麦分子标记辅助育种技术有关。国内外对Wx基因效应的研究主要利用缺体-四体系、重组自交系或近等基因系,还未见有利用遗传背景相同的BC5F2代回交改良群体的报道。 糯性位点近等基因系是小麦淀粉品质育种的重要材料,而我国目前还没有一套中国栽培小麦遗传背景的糯性位点近等基因系。为了选育部分糯小麦、全糯小麦和中国栽培小麦遗传背景的糯性位点近等基因系,我们利用Wx蛋白电泳和高效实用的分子标记技术体系来鉴定糯小麦杂交后代的基因型,结果证明该体系能有效地用于糯小麦的分子标记辅助育种。以中国春糯性位点全套近等基因系为研究材料,对小麦Wx基因的6个STS标记和1个CAPS标记进行了筛选,改良PCR扩增条件以及产物检测方式后,从这些标记中筛选出3个标记,包括鉴定Wx-A1、Wx-D1位点的2个共显性STS标记和Wx-B1位点的1个显性STS标记。利用上述3个分子标记从BC5F2 代回交改良群体中筛选出了8种Wx基因型,经卡方检验,其分离比符合3对基因的分离比例,其中基因型为aabbdd的植株有2株,直链淀粉含量分别为1.81%和0.82%,为全糯小麦;基因型为AAbbdd,aabbDD的部分糯性植株各有1株,直链淀粉含量分别为15.24%和17.57%。以上4株植株的农艺性状和品质性状接近回交亲本“川育12”,并明显优于全糯材料“98Y1441”,表明采用回交法与Wx基因分子标记辅助选择相结合,有助于培育高产、优质的全糯和部分糯小麦。同时,本研究中建立的分子标记技术体系,也为选育具有中国栽培小麦遗传背景的糯性位点近等基因系奠定了基础。 在基因型鉴定的基础上,利用糯小麦杂交后代BC5F2代回交改良群体研究了各基因缺失降低直链淀粉含量的效果和各基因合成直链淀粉的能力,以及直链淀粉含量与农艺性状、品质性状、淀粉糊化特性等的相关性。缺失不同Wx基因的8种基因型,直链淀粉含量差异显著。研究单缺失基因型发现,减少效应最大的是Wx-B1b基因,Wx-B1b和Wx-D1b基因没有显著差异,减少效应最小的是Wx-A1b基因。研究双缺失基因型发现,Wx基因合成直链淀粉的能力,Wx-B1a基因最高,Wx-A1a基因最低,而Wx-B1a和Wx-D1a基因差异很小;直链淀粉含量与株高、穗长、小穗数、穗粒数、千粒重等农艺性状相关不显著,表明淀粉品质育种可以与高产育种实现有机结合;直链淀粉含量与SDS-沉降值呈显著负相关(r=-0.726),说明直链淀粉含量降低在一定程度上有利于提高小麦营养与加工品质,这一结果至今未见有文献报道;全糯类型的淀粉糊化特性与其他类型显著不同,具有最高的峰值粘度和稀懈值,最低的低谷粘度、最终粘度、反弹值、峰值时间、糊化温度、起始糊化温度,表明糯小麦淀粉在食品和工业上具有特殊用途;稀懈值与直链淀粉含量呈极显著负相关(r=-0.969),其他粘度参数与直链淀粉含量呈显著正相关(最终粘度r=0.797,低谷粘度r=0.910、反弹值r=0.954、峰值时间r=0.970、糊化温度r=0.962、起始糊化温度r=0.932)。以上结论可为糯小麦品种选育和淀粉品质改良提供理论依据。 Waxy wheat is very important in food processing industry, starch processing industry and the other industries, so it is a focus of wheat research in many countries these years. Foreign wheat breeders have not conquered the difficulty of high yield combined with waxy character, and there is no waxy wheat variety with high protein and strong gluten in China at present,all of which were caused by lacking proper breeding methods and effective, applied molecular markers-assisted selection technique at a certain extent. Until now, research about the effect of waxy genes mainly depended on nullisomic-tetrasomic lines, recombinant lines or near-isogenic lines, and it is lacking the reports of using improved BC5F2 backcross progenies under the common genetic background. Near-isogenic lines at the Wx loci are important materials for wheat starch quality breeding. However, there are no such lines under the Chinese cultivated wheat genetic background. To develop partial waxy wheats, waxy wheats and near-isogenic lines at the Wx loci under the Chinese cultivated wheat genetic background, we use SDS-PAGE of waxy proteins and effective, applied molecular marker-assisted selection technical system to identify the genotype of waxy wheat’s progenies. The results indicated that such a system is applicable in waxy wheat’s molecular marker-assisted selection effectively. A series of Chinese Spring Wx loci near-isogenic lines were used to identify the specific bands of six STS markers and one CAPS marker of Wx genes. After optimizing PCR amplification and separating of PCR products, three co-dominant and dominant STS-markers were identified at the Wx-A1, Wx-D1 and Wx-B1 loci, respectively, which were used to identify the genotype of waxy wheat’s progenies. Eight Wx genotypes were developed from the improved BC5F2 backcross progenies, which follows Mendelian segregation. Among them, there were two aabbdd waxy plants whose amylose content in the BC5F3 seeds were 1.81% and 0.82%, respectively. In addition, there were partial waxy plants (AAbbdd and aabbDD) whose amylose content in the BC5F3 seeds were 15.24 % and 17.57%, respectively. Most agronomic and quality traits of these four plants resembled those of the recurrent parent “Chuanyu 12”, and superior to waxy wheat parent “98Y1441”. This shows that backcross approach in combination with molecular marker-assisted selection of waxy genes is helpful to develop partial and full waxy wheat with good traits in the waxy wheat breeding program. At the same time, molecular marker-assisted selection technical system in this paper, also establish the base for breeding the near-isogenic lines at the Wx loci under the Chinese cultivated wheat genetic background. According to the results of genotype identification, we use waxy wheat’s improved BC5F2 backcross progenies to verify the effects of null alleles on reducing amylose content and determine the amylose synthesis capacity of each Wx gene independently, and investigate the relativity among amylose content with agonomic traits, quality traits, starch pasting properties respectively. There was significant difference in amylose content of the eight genotypes carrying different null Wx alleles. The reducing effect of the single null alleles was the most significant in Wx-B1b, followed by Wx-D1b and Wx-A1b, and there was no significant difference between Wx-B1b and Wx-D1b. The results of the double null lines further demonstrated that for the capacity of amylose synthesis, Wx-B1a was the highest, followed by Wx-D1a and Wx-A1a, and there was no significant difference between Wx-B1a and Wx-D1a. Amylose contents of the eight genotypes were not significantly correlated with plant height, spike length, spikelets per spike, grains per spike, 1000-grain weight, which showed that starch quality breeding could integrate with high yield breeding. Amylose contents of the eight genotypes were negatively significantly correlated with SDS-sedimentation value(r=-0.726), which suggested that reduction in amylose content is propitious to improve quality at a certain extent. Starch pasting properties of the full waxy type was significantly different from the other seven types, with the highest peak viscosity and breakdown, and lowest valley viscosity, final viscosity, setback, peak time, pasting temperature and starting pasting temperature. It indicated that waxy wheat starch has special use in food and industry. Breakdown was negatively significantly correlated with amylose contents (r=-0.969), and the other parameters were positively significantly correlated with amylose contents (r=0.797 for final viscosity, r=0.910 for trough viscosity, r =0.954 for setback, r =0.970 for peak time, r=0.962 for pasting temperature and r=0.932 for starting pasting temperature ). The results of the study are very useful for waxy wheat variety breeding and starch quality improvement.

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本研究应用微波消解ICP-AES 法对62 个小麦品种及3 个地区土壤的锌铁硒含量进行了分析测定,发现不同小麦品种中微量元素含量差异很大,姊妹系间也存在差异。含铁量最高与最低的小麦品种铁含量相差29.68mg/kg。含锌量最高与最低的小麦品种锌含量相差46.70 mg/kg。含硒量最高与最低的小麦品种硒含量相差0.056 mg/kg。对不同地点的小麦及土壤中锌铁硒含量进行方差分析,发现双流和西昌两地种植小麦的铁含量和硒含量均有显著差异,西昌和荣县种植的锌含量有显著差异。在3 个地点中双流种植小麦硒含量最高,西昌种植小麦的铁和锌含量最高。 通过对小麦微量元素含量与土壤中微量元素含量进行了相关性分析,结果表明:小麦中的锌铁含量与土壤中的锌铁含量呈显著正相关,土壤中铁与锌含量呈极显著正相关,小麦中铁与锌含量也呈极显著正相关。随着土壤微量元素锌铁的提高,小麦中的锌铁元素含量同时提高,而且小麦对两种元素的吸收互相促进。土壤中的硒含量与锌铁含量呈负相关。小麦中硒含量也与锌铁含量也呈负相关。说明锌和铁与硒互相拮抗。小麦硒含量与土壤硒含量呈正相关,但不显著。表明土壤硒含量可以影响小麦硒含量,但不是决定因素,小麦硒含量与小麦自身因素有关。 对姊妹系G290(高硒含量)和G289(低硒含量)进行抗重金属胁迫和抗旱性实验发现,高硒品种G290的抗逆性优于低硒品种G289。 利用RAPD 技术对7 个姊妹系进行遗传差异分析发现,高硒材料G290出现了特异条带,分别标为1、2、3、4,其他姊妹系品种中未发现特异条带,回收4 条特异条带并连接转化,得到目的片段1、2、3 的重组子,进行测序。NCBI 中结果显示没有找到植物中的同源序列,说明特异序列可能是未发现的基因片段,推测可能与小麦硒含量有关,有待进一步研究。 以上研究结果,对小麦营养研究及功能性小麦的筛选和栽培具有指导作用。 In this study, we determinated the contents of zinc, iron, selenium in 62 wheat cultivars and soil samples of three regions by method of microwave digestion/ ICPAES,found that there was great difference of zinc, iron, selenium contents in different wheat cultivars as well as different sister lines. Iron content difference was 29.68 mg/kg between the highest-iron-content cultivar and the lowest one, and zinc content difference was 46.70 mg/kg , selenium content difference was 0.056 mg/kg. Anova analysis was made on contents of zinc, iron, selenium in wheat and soil samples of different locations, significant differences of Fe and Se contents were found between wheat in Shuangliu and Xichang, significant difference of Zn content was found between wheat in Xichang and Rongxian. Se content in wheat of Shuangliu was highest, Fe and Zn contents in wheat of Xichang were highest. Relativity analysis was made on three trace elements in Wheat and in soil, the result showed that there was significant positive correlation of zinc, iron content between in Wheat and in soil, as well as between Fe and Zn both in wheat and in soil. With the improving of Zn, Fe contents in soil, contents of Zn and Fe in wheat increased and absorption of Zn and Fe in wheat will mutual promote. Negative correlation of Se and Zn contents was found in wheat and soil, but not significant, that meant the antagonism of Se and Zn. Positive correlation of Se content in wheat and soil was found. High selenium content G290 and low selenium content G289 in sister lines were selected for heavy metal stress and drought resistance experiments, the result showed that the resistance of high-selenium-content cultivar was better than low selenium one. Analysis on genetic difference was made by RAPD, and specific bands were selected, marked 1,2,3,4, no more specific bands were found in other sister lines.4 bands were recovered, ligated to T-vector and transformed E.coli. Three recombinant plasmids were obtained and sequenced. NCBI Blast showed there was no homology with other plants. It implied that these fragments probably be new genes and maybe were related to selenium in wheat. It needs further research. This paper would be useful for the study of wheat nutrition as well as selection and cultivation of functional wheat.

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We derive the generalized Friedmann equation governing the cosmological evolution inside the thick brane model in the presence of two curvature correction terms: a four-dimensional scalar curvature from induced gravity on the brane, and a five-dimensional Gauss-Bonnet curvature term. We find two effective four-dimensional reductions of the generalized Friedmann equation in some limits and demonstrate that the reductions but not the generalized Friedmann equation can be rewritten as the first law of equilibrium thermodynamics on the apparent horizon of thick braneworld.

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in this Raper, based on distance matrix and branch vertex of atomes in a molecule, a new topological index (Y(x)) has been developed to be used in research on physical and chemical properties of alkanes. It is concluded that this index bears good structure selectivity and relativity when the results from index were compared with that of other ones.

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SNARE蛋白家族是所有真核细胞胞吐及分泌作用中的关键因子,由其介导的运输囊泡膜与靶膜的锚靠、融合为胞内蛋白的运出提供了一条重要途径。体外试验表明,Syntaxin6-Syntaxin7-Vti1b,SNAP-23-Syntaxin4等SNARE核心蛋白之间精确的相互作用是哺乳动物巨噬细胞肿瘤坏死因子α (TNF-α)运输和分泌的必备条件,在机体非特异性免疫应答反应过程中起重要作用。 本研究受上述启示,旨在揭示SNARE蛋白在海洋鱼类免疫细胞内重要细胞因子白细胞介素1β (IL-1β)的分泌过程中的作用。参照Percoll密度梯度离心技术,从鲈鱼头肾组织分离纯化巨噬细胞进行稳定培养;利用RT-PCR方法克隆出鲈鱼t-SNARE蛋白SNAP-23和Syntaxin3的部分cDNA序列,再结合先前克隆的VAMP2和已知的鲈鱼IL-1β,TNF-α和IL-8的基因序列,设计特异性引物。利用Real-time PCR技术在mRNA水平上精确测定鲈鱼巨噬细胞中上述6种基因在革兰氏阴性菌脂多糖(LPS)分子刺激下的表达变化,发现SNAP-23基因与三种细胞因子基因的表达正相关;通过免疫印迹检测SNAP-23蛋白表达变化,利用酶联免疫吸附试验(ELISA)检测IL-1β的分泌水平,在蛋白水平上验证了SNAP-23表达与IL-1β分泌的正相关性;利用5`RACE和3`RACE技术克隆出鲈鱼SNAP-23全长基因,结合定点突变策略和靶向PCR克隆手段,构建鲈鱼SNAP-23野生型融合质粒pEGFP-SNAP-23wt,Cys缺失突变融合质粒pEGFP-SNAP-23ΔCys和模拟E型肉毒神经毒素(BoNT/E)切割突变融合质粒pEGFP-SNAP-23ΔBoNT/E,以及鲈鱼IL-1β野生型融合表达质粒IL-1β-pEGFP和IL-1β-pEYFP。所有融合蛋白均在鲈鱼巨噬细胞内成功表达,结合ELISA实验结果发现,SNAP-23野生型的表达对IL-1β的分泌有促进作用,而Cys缺失突变体的表达则抑制IL-1β向胞外分泌。首次证实了鱼类巨噬细胞内SNAP-23蛋白在IL-1β分泌过程中的重要作用。此外通过与GFP共表达,定位了IL-1β分子在巨噬细胞内的分布,发现新合成的IL-1β分子很可能像TNFα一样经“内质网-胞质-伪足-胞外” 的分泌路径运出胞外。

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本文通过胶州湾围隔实验、微藻培养实验研究了海洋微藻产生溶解有机物的三维荧光特性,并初步利用经验正交函数对三维荧光光谱图进行了主成分分析,通过东海取样研究了东海荧光溶解有机物的时空分布特征,并对荧光溶解有机物的来源进行了分析。得到了一些初步结论: 胶州湾围隔实验中不同营养盐培养结果表明浮游植物可产生类蛋白和类腐殖质荧光,类蛋白荧光峰由类酪氨酸(tyrosine-like)荧光峰和类色氨酸(tryptophan-like)荧光峰组成,主要位置为Exmax/Emmax=270nm/290~310nm,Exmax/Emmax= 270~290/320~350的荧光峰强度比较弱;在Exmax/Emmax=250~260/380~480nm(A峰)、Exmax/Emmax=310~320/380~420nm(C峰)和Exmax/Emmax=330~350/420~480nm(M峰)位置均出现零散的类腐殖质荧光峰,其中以A峰为主。类酪氨酸荧光强度明显高于类腐殖质荧光强度。浮游植物量降低时,类酪氨酸荧光强度与叶绿素a浓度呈明显的负相关。硅藻和甲藻产生的类酪氨酸和类色氨酸荧光强度之间具有较好的相关性,两者来源相似, 并且甲藻与硅藻相比能够产生更多的类蛋白荧光物质。不同环境下类腐殖质混合物的组分比例不同,甲藻生长环境下相对于硅藻具有较低的A:C比值。 在实验室培养中肋骨条藻(Skeletonema costatum)、塔玛亚历山大藻(Alexandrium tamarense)、微小亚历山大藻(Alexandrium mimutum)、锥状斯氏藻(Scrippsiella trochoidea)、东海原甲藻(Prorocentrum donghaiense)及海洋原甲藻(Prorocentrum micans)的实验结果表明,微藻在生长过程中产生出荧光溶解有机物,中肋骨条藻为代表的硅藻主要产生类腐殖质荧光物质,而甲藻在指数增长期主要产生类蛋白荧光物质。进入消亡期后类蛋白荧光和类腐殖质荧光强度迅速增大,原因可能是衰老、死亡藻细胞的破碎释放出大量的荧光有机物质所致,此外还有细菌对非荧光有机物进一步降解。塔玛亚历山大藻、微小亚历山大藻、东海原甲藻及海洋原甲藻的类蛋白荧光强度在消亡后期由于细菌降解或光降解等因素而降低。同属微藻产生的荧光物质相似,例如塔玛亚历山大藻与微小亚历山藻、东海原甲藻与海洋原甲藻,但具体荧光峰位置有所不同。利用经验正交函数能够对三维荧光光谱谱图进行主成份分析。 在利用三维荧光光谱法研究长江口海域台风前后不同站位荧光溶解有机物荧光特性及分布特征的结果表明,长江口海区主要的荧光溶解有机物荧光峰为T峰、S峰和A峰。风前和风后的类色氨酸分别来源于相似物质。风前,在表层浮游植物能够产生类蛋白荧光物质,而底层类蛋白荧光物质不受浮游植物的影响,长江冲淡水能够带来部分类蛋白荧光物质;表层的类腐殖质不受浮游植物的影响,而底层的浮游植物在降解过程中能够产生一部分类腐殖质,并且长江冲淡水对表层和底层的类腐殖质来源均有很大贡献。风后,表层的类色氨酸与叶绿素a浓度不呈相关性,而底层却呈正相关,另外表层和底层的类色氨酸均受到长江冲淡水的影响;表层和底层的类腐殖质与叶绿素a均没有相关性,但受陆源影响显著,长江冲淡水能带来类腐殖质。

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With the deepening development of oil-gas exploration and the sharp rise in costs, modern seismic techniques had been progressed rapidly. The Seismic Inversion Technique extracts seismic attribute from the seismic reflection data, inverses the underground distribution of wave impedance or speed, estimates reservoir parameters, makes some reservoir prediction and oil reservoir description as a key technology of Seismic exploration, which provides a reliable basic material for oil-gas exploration. Well-driven SI is essentially an seismic-logging joint inversion. The low, high-frequency information comes from the logging information, while the structural characteristics and medium frequency band depend on the seismic data. Inversion results mainly depend on the quality of raw data, the rationality of the process, the relativity of synthetic and seismic data, etc. This paper mainly research on how the log-to-seismic correlation have affected the well-driven seismic inversion precision. Synthetic, the comparison between middle –frequency borehole impedance and relative seismic impedance and well-attribute crossplots have been taken into account the log-to-seismic correlation. The results verify that the better log-to-seismic correlation, the more reliable the seismic inversion result, through the analysis of three real working area (Qikou Sag, Qiongdongnan basin, Sulige gas field).

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Facing the problems that Dagang region of Huanghua Depression has high exploration degree and its remaining resource potential and structure are not clear, the theory of Petroleum Accumulation System (PAS) is applied to divide and evaluate the oil/gas systems quantitatively. Then, the petroleum accumulation systems are taken as units to forecast and analyse the oil/gas resources and their structure using statistical methods of sampling analysis of discovery process model and generalized pareto distribution model. The exploration benefit of the unit is estimated using exploration simulation methods. On the basis of the above study, the resource potential of Huanghua Depression is discussed.Huanghua Depression can be diveded into four petroleum accumulation systems, i.e. North PAS5 Middle Qibei PAS, Middle Qinan PAS and South PAS. Each PAS can be diveded futher into several sub- PASs. Using the basic princple of Analytical Hierarchy Process, the method of quantitative evaluation of PAS is established. Then the elements and maturity of PAS are evaluated quantitatively.Taking migration and accumulation units and sub-PASs as prediction units, sampling analysis of discovery process model and generalized pareto distribution model are applied comparatively to forecast the resource structure of eight migration and accumulation units in six PASs of medium-high exploration degree. The results of these two methods are contrasted and analyzed. An examination of X2 data of these two models from exploration samples shows that generalized pareto distribution model is more effective than sampling analysis of discovery process model in Huanghua Depression. It is concluded that minimum and maximum size of reservoir and discovery sequence of reservoirs are the sensitive parameters of these two methods.Aiming at the difficult problem of forecast in low exploration degree, by analysis of relativity between resource parameters and their possible influential geological factors, forecast models for resource parameters were established by liner regressing. Then the resource structure is forecasted in PASs of low exploration degree.Based on the forecast results, beginning with the analysis of exploration history and benefit variation, the exploration benefit variation of the above PASs is fitted effectively using exploration simulation method. The single well exploration benefit of remaining oil resource is also forecasted reasonably.The results of resource forecast show that the total oil resources ofHuanghua Depression amount to 2.28 b illion ton. By the end o f 2 003, the accumulative total proved oil reserve is 0.90 billion ton and the remaining oil resources is 1.38 billion ton. The remaining oil resource is concentrated in Kongdian-Dengmingshi, Banqiao-Beidagang, Qidong-Yangerzhuang and Baidong-Qizhong sub-PASs.