Pombe: A gene-finding and exon-intron structure prediction system for fission yeast

A special program developed by the authors, called Pombe, identifies protein coding regions in the Schizosaccharomyces pombe genome. Linear discriminant analysis was applied to predict 5′-terminal, internal, 3′-terminal exons (coding-exon) and introns. The accuracy of the prediction was tested by cross verifications. The sensitivity, specificity and correlation coefficient for the internal exon prediction were 98·5%, 99·9% and 98·3% respectively at the nucleotide level. Open reading frames were studied and used to predict intron-less genes: 99·0% of such genes were identified with correct stopping sites. The gene structure was determined by dynamic programming and the prediction achieved 97·0% correlation coefficient at the nucleotide level. The program is available at http://clio.cshl.org/genefinder. © 1998 John Wiley & Sons, Ltd.     

Random and targeted gene integrations through the control of non‐homologous end joining in the yeast Kluyveromyces marxianus

Kluyveromyces marxianus DMKU3‐1042 is a thermotolerant yeast strain suitable for high‐temperature ethanol fermentation and genetic engineering with linear DNA. We have developed a highly efficient random gene integration method with a frequency that exceeds 2.5 × 10⁶ transformants/µg linear DNA, a figure comparable to what is observed with autonomously replicating plasmid transformation in Saccharomyces cerevisiae. To establish the mechanism of random integration in DMKU3‐1042, we identified and deleted the K. marxianus KU70 gene, which is known to be involved in the non‐homologous end‐joining (NHEJ) pathway. In yeast lacking KU70, high‐frequency non‐homologous gene integration was abolished and the Kmku70 mutants showed 82–95% homologous gene targeting efficiencies using homologous sequences of 40–1000 bp. These results indicate that the highly efficient NHEJ pathway can be utilized with random gene disruption techniques such as transposon mutagenesis and plasmid‐free gene manipulations in K. marxianus. Copyright © 2009 John Wiley & Sons, Ltd.     

线性算子束谱的一些性质刻画

研究了希尔伯特空间上算子束的特性.利用算子谱理论及空间分解的技巧,通过构造算子矩阵的方法,得到线性算子束Aλ＋B谱的性质及Aλ＋B的非正规性的充分必要条件.     

草酸青霉线性五肽生物合成的比较转录组分析

草酸青霉(Penicillium oxalicum)是一种重要的植物生防菌,从三峡河岸带分布的草酸青霉中,分离到一种线性五肽,该物质对柑橘致腐菌指状青霉(P.digitatum)具有极强的抑制作用.为了分析该五肽的生物合成机制,本研究采用BGISEQ-500平台,测定了3株不同五肽含量的草酸青霉(114-2,SG-4,...     

关于线性泛函的一个延拓定理

在哈恩-巴拿赫泛函延拓定理的基础上,对更广泛的泛函类-凸泛函类,证明了线性泛函的可延拓性,并进一步得出了定理2的结果。     

二元子空间格代数上的保一秩线性映射

给出Hilber空间H上的两个非平凡不变子空间M,N构成的子空间格代数Alg{M,N},到Alg{M,N）之间的保一秩线性映射,其中Alg{M,N）={A∈B（H）,AM∩→M,AN∩→N）,B（H）为H上的全体有界线性算子空间,并且给出一秩算子在M,N,M⊥N⊥之间的不同单映射线变换形式及在彤上的应用．     

线性微分多项式的值分布与线性微分方程的解增长(英文)

对线性微分多项式的值分布与线性奧分方程解的增长性进行了研究,并得到关于线性奧分多项式零点与极点的一个基本不等式.这一结果不仅蕴涵了Frank-Weissenborn不等式,而且揭示了线性微分多项式的值分布与线性微分方程解的增长性之间的一种联系.作为此结果的应用,Hayman-Yang不等式及几个著名的定理被推广.例子表明,文中所给定理的条件是基本的.     

经验回归法计算织物紧度

通过对影响织物紧度的结构因素进行分析,采用回归分析的方法,建立了二者之间的回归方程,从数学角度验证了织物紧度公式,并用纱线的线密度代替纱线的直径计算织物的紧度,减少了计算的繁琐和误差。     

Na2SO4浸提-四苯硼钠比色法检测窖泥中钾含量的方法探讨

四苯硼钠比色法测定窖泥钾含量，对不同的钾标准液浓度进行分段处理。结果表明：钾标准液浓度小于10mg／L时，其线性相关性较差，不符合朗伯比尔定律。在钾标准液浓度为大于等于10mg／L时，回归曲线线性良好，R^2值达到0．9998，符合朗伯比尔定律。     

婴儿配方乳粉的线性程序设计

本文利用计算机了３－６个月婴儿与配方奶粉的配方，配方中，奶粘占４６．５％，小米占２０．４％，大米中１８．０％，黄豆粉占１３．０％，乳糖占２．０％，黄油占０．１％。依此配方可满足婴儿的生长需要。     

Uncertainty of pesticide residue concentration determined from ordinary and weighted linear regression curve

Determination of pesticide residues is based on calibration curves constructed for each batch of analysis. Calibration standard solutions are prepared from a known amount of reference material at different concentration levels covering the concentration range of the analyte in the analysed samples. In the scope of this study, the applicability of both ordinary linear and weighted linear regression (OLR and WLR) for pesticide residue analysis was investigated. We used 782 multipoint calibration curves obtained for 72 different analytical batches with high-pressure liquid chromatography equipped with an ultraviolet detector, and gas chromatography with electron capture, nitrogen phosphorus or mass spectrophotometer detectors. Quality criteria of the linear curves including regression coefficient, standard deviation of relative residuals and deviation of back calculated concentrations were calculated both for WLR and OLR methods. Moreover, the relative uncertainty of the predicted analyte concentration was estimated for both methods. It was concluded that calibration curve based on WLR complies with all the quality criteria set by international guidelines compared to those calculated with OLR. It means that all the data fit well with WLR for pesticide residue analysis. It was estimated that, regardless of the actual concentration range of the calibration, relative uncertainty at the lowest calibrated level ranged between 0.3% and 113.7% for OLR and between 0.2% and 22.1% for WLR. At or above 1/3 of the calibrated range, uncertainty of calibration curve ranged between 0.1% and 16.3% for OLR and 0% and 12.2% for WLR, and therefore, the two methods gave comparable results.     

XCY—1型线性测长仪原理与应用

XCY-1型线性测长仪为电子控制的单茧丝长测试仪器,具有自动定长、切断检测、快速无噪音制动、缫丝张力小且稳定等特点。适用于丝厂一粒缫设备及其它抗捻强度极低的线性状体长度测量。     

‘Marker Swap’ Plasmids: Convenient Tools for Budding Yeast Molecular Genetics

One-step gene disruption constructs for disruption of HIS3, LEU2, TRP1 or URA3 with each of the other three markers have been constructed. All of these constructs have been tested and found to effectively convert markers either in gene disruptions or on plasmids. The ‘swapped’ strains allow the unambiguous genetic analysis of synthetic phenotypes with multiple genes, even if the original gene disruptions were made with the same marker. They also allow introduction of multiple plasmids in a single transformant, even if the original plasmids had the same marker, and allow transformation of plasmids into strains containing gene disruptions made with the same marker that is on the plasmids. These ‘marker-swap’ plasmids therefore eliminate the need for much subcloning to change markers. Marker-swapped alleles are acceptably stable mitotically and meiotically for most applications.© 1997 John Wiley & Sons, Ltd.     

基于16S rRNA基因与相关基因序列分析格氏乳球菌亲缘关系

通过PCR扩增7株分离自传统发酵乳制品中的格氏乳球菌的dnaA、rpoB、recA基因,将扩增产物测序,测得的序列构建系统发育树,进行分类鉴定.同时,比较了这三个基因位点与16S rRNA基因揭示的格氏乳球菌种内菌株间以及其与乳酸乳球菌种间的亲缘关系的远近.结果表明,dnaA、rpoB、recA基因能够有效的鉴定出格氏乳球菌,且比16S rRNA基因更清晰地揭示了格氏乳球菌菌株间以及其与乳酸乳球菌种间的亲缘关系,特别是将3个管家基因联合起来,亲缘关系更明确,验证了多个管家基因是研究细菌亲缘关系的有力工具.     

重组原核表达载体pQE-30-luxS的构建与表达

构建原核表达载体pQE-30-luxS,并在大肠杆菌中诱导表达融合蛋白。以植物乳杆菌KLDS1.0391的基因组DNA为模板,采用PCR方法扩增luxS基因,同时克隆到pMD18-T simple中,经鉴定正确后与表达载体pQE-30连接,将重组质粒pQE-30-luxS转化到E.coli M15中,异丙基-β-D-硫代吡喃半乳糖苷（IPTG）诱导表达,表达产物进行SDS-PAGE鉴定。结果表明原核表达载体pQE-30-luxS构建成功,测序证实插入的目的片段与已知luxS基因序列一致,且LuxS蛋白在大肠杆菌中成功表达。该结果为体外合成信号分子AI-2奠定了基础。      

一类线性分式规划问题的全局优化方法

针对一类线性分式规划问题,给出一个新的分支定界算法.算法的主要特点是在建立原问题等价的松弛线性规划问题时,利用对数函数和指数函数的单调性和凹凸性,提出了一个新的二级松弛规划来确定最优值的下界,这可以用于改善算法的收敛速度.通过对松弛线性规划问题可行域的细分以及一系列松弛线性规划问题的求解过程,从理论上证明了此算法能收敛到初始问题的全局最优解.并通过数值算例证明了算法的有效性.     

高速织造与纱线特性的关系

对高速织造时经线张力的变化,伸长与弹性及摩擦特性等方面做了理论性探讨,对伟线张力,纬线结构和材料与速度的关系作了分析。提出除传统强造工艺因素外,高速织造时的织物幅宽,综框数目,梭口形状等对经线动态负荷的影响,阐明引纬控制装置对缩小纬纱张力波动范围,降低少断头率起到秉作用。     

广州市售豆制品转基因成分的检测与分析

为了解广州市市售豆制品的转基因情况,对广州市售散装豆制品和预包装豆制品分别进行抽样检验.采用改良十六烷基三甲基溴化铵（CTAB）法提取大豆DNA,利用核酸定性PCR、实时荧光PCR及环介导等温扩增技术（LAMP）对外源基因CaMV5S,NOS和EPSPS进行检测.调查共抽检豆制品207份,研究结果表明,在检测的159份散装豆制品中,87份检出转基因成分;在48份预包装豆制品中,18份检出转基因成分.散装豆制品无任何食品标签,而预包装豆制品均无转基因食品标识.