演化极端结合分支分类方法

从生物演化的逆方向考虑,提出一种聚合的分支分类运算方法,称为演化极端结合分支分类法。文章阐明其设计思路、演算步骤,并以实例具体说明其演算过程。最后以演化长度系数、合理解与合理方法等概念,对演化极端结合法进行评价。     

不同取样方式在稻田节肢动物采集中的效率评估

水稻是我国主要粮食作物,每年都会因虫害造成大量的经济损失,为了挽回害虫造成的损失,必须对害虫进行防治。田间节肢动物群落调查是评价害虫防治效果的重要依据,取样方式对节肢动物群落调查的准确性具有重要的影响。另外,对转基因作物对稻田生物多样性安全性进行评价时,取样方式对多样性评价的准确性也具有重要的影响。本文采用吸虫器法、盆拍法和马氏网诱集法3种取样方式进行稻田节肢动物调查,并评估不同取样方式的采集效率。得到的结果有:1.采集到的节肢动物物种数:马氏网诱集法吸虫器法盆拍法;2.采集的节肢动物数量:盆拍法吸虫器法马氏网诱集法;3.吸虫器取样法在调查叶蝉科、秆蝇科、茧蜂科、姬蜂科、金小蜂科、缘腹细蜂科、蕈蚋科时,取样效率较高;4.盆拍取样法在调查叶蝉科、瘿蚊科、微蛛亚科、跳蛛科、狼蛛科、猫蛛科、弹尾虫目、飞虱科时,取样效率较高;5.马氏网诱集法在调查缟蝇科和毛蠓科时取样效率较高。马氏网诱集法善于采集具有飞行能力的节肢动物;吸虫器法对不同习性的节肢动物采集效果均较高;盆拍法适合采集活动于水稻基部的节肢动物。     

Method for rapid screening of pesticide mineralization in soil

A method has been developed for the analysis of (14)CO(2) evolution from the mineralization of (14)C-labelled organic compounds in soil samples. The new method is less space demanding and substantially cuts down laborious manual work compared to the traditional incubation bottle method used. Furthermore, the use of scintillation cocktail is largely reduced with the new method. In the new method, (14)CO(2) is trapped in filter paper held in the lid of a 20 ml glass vial by surface tension. The trapping solution used is Ca(OH)(2), which fixates CO(2) in the filter paper and the analysis of trapped (14)CO(2) is done using the Cyclone trade mark Storage Phosphor system. The lids are placed in a 32 well holder and exposed to a phosphor screen prior to scanning in a Cyclone trade mark scanner. The new filter method has been tested and compared to results obtained using the traditional method. The results show good agreement but due to a smaller capacity for CO(2) with the filter method compared to the traditional method, the interval between sampling has to be shorter using the filter method when the CO(2) development is high. The detection limits for the filter method is higher compared to the traditional method. With the filter method, the level of radioactivity has to exceed 300 dpm before detection is possible, while the same limit for the traditional method is around 30 dpm. On the other hand, the gas trapping faster and the efficiency is higher with the filter method.     

A new semiparametric estimation method for accelerated hazard model

The accelerated hazard model has been proposed for more than a decade. However, its application is still very limited, partly due to the complexity of the existing semiparametric estimation method. We propose a new semiparametric estimation method based on a kernel-smoothed approximation to the limit of a profile likelihood function of the model. The method leads to smooth estimating equations and is easy to use. The estimates from the method are proved to be consistent and asymptotically normal. Our numerical study shows that the new method is more efficient than the existing method. The proposed method is employed to reanalyze the data from a brain tumor treatment study.     

改进的SDS-CTAB法提取濒危植物连香树总DNA

对珍稀濒危植物连香树(Cercidiphyllum japonicum)的6种总DNA提取方法进行了对比试验,结果表明改进的SDS-CTAB法更适合于连香树总DNA提取。该方法提取的DNA经紫外消光值检测,其A260/A280为1.8532,优于CTAB法(1.4872)、SDS法(1.3552)、PVP法(1.5079)、尿素法(1.1858)和高盐低pH法(1.4534)。琼脂糖凝胶电泳和PCR扩增结果也得出同样的结论。     

深圳地区参考作物蒸散量计算方法适用性分析

根据深圳1998~2007日值气象资料,以4种方法计算参考作物蒸散量,并以FAO Penman-Monteith公式计算结果为标准,评价其他各公式在深圳的适用性。结果表明:Irmark-Allen公式的月平均参考作物蒸散量及年参考作物蒸散量与Penman-Monteith公式结果没有显著差异,与Hargreaves公式和Pristley-Taylor公式计算结果差异显著,Hargreaves最大,Pristley-Taylor最小;Irmark-Allen公式、Pristley-Taylor公式与Penman-Monteith公式的相关性较高,而Hargreaves相关性较低。Irmark-Allen法可作为深圳地区缺少相关气象资料条件下计算ET0较理想的替代方法。     

Measurement of DNA with an automatic spectrophotometer

A method that uses an automated spectrophotometer to read microtiter plates in a modification of the diphenylamine method of DNA determination in tissue extracts, is presented. The micromethod saves technician time, and reduces exposure to acetic acid fumes. The reproducibility of the method is superior to the manual method. Fewer pipetting steps are required, and the method is suited to large batches of samples.     

用气相色谱-质谱联用比较牛耳草代谢物的提取方法

通过比较不同的提取方法对牛耳草新鲜和脱水叶片中代谢物的提取效率,旨在建立一种可以有效鉴定并分析牛耳草脱水过程中关键小分子代谢物的种类和含量变化的方法,为研究植物耐脱水分子机制提供技术方法。本研究以气相色谱-质谱联用(GC-MS)为分析方法,对复苏植物牛耳草代谢物提取方法进行比较。从提取总色谱峰数目、提取效率、代谢物保留时间和提取效率稳定性等方面比较甲醇溶液(A法)和甲醇-氯仿-水溶液(B法)两种提取方法的提取效果。对牛耳草新鲜样品提取结果表明,B法提取的总色谱峰数目多于A法;对9种共有代谢物的提取效率比较结果表明,B法的提取效率高于A法;对10种色谱峰的保留时间和提取效率的方法学考察结果表明,两者保留时间RSD(相对标准偏差)值均小于1%,A法提取效率的RSD值≤10%的比例为50%,B法的为100%。A法对干样的提取色谱峰数目远少于鲜样,而B法对干样的提取色谱峰数目和鲜样没有显著差异,保留时间RSD值均小于1%,提取效率的RSD值与鲜样没有差异,稳定性良好。     

Approximating identity-by-descent matrices using multiple haplotype configurations on pedigrees

Identity-by-descent (IBD) matrix calculation is an important step in quantitative trait loci (QTL) analysis using variance component models. To calculate IBD matrices efficiently for large pedigrees with large numbers of loci, an approximation method based on the reconstruction of haplotype configurations for the pedigrees is proposed. The method uses a subset of haplotype configurations with high likelihoods identified by a haplotyping method. The new method is compared with a Markov chain Monte Carlo (MCMC) method (Loki) in terms of QTL mapping performance on simulated pedigrees. Both methods yield almost identical results for the estimation of QTL positions and variance parameters, while the new method is much more computationally efficient than the MCMC approach for large pedigrees and large numbers of loci. The proposed method is also compared with an exact method (Merlin) in small simulated pedigrees, where both methods produce nearly identical estimates of position-specific kinship coefficients. The new method can be used for fine mapping with joint linkage disequilibrium and linkage analysis, which improves the power and accuracy of QTL mapping.     

Research on the Top-Down Parsing Method for Context-Sensitive Graph Grammars

The parsing problem is one of the key problems of graph grammars. The typical parsing algorithm uses the bottom-up method. The time-complexity of this method is high, and it is difficult to apply. In order to reduce the time-complexity, this paper uses the top-down method for parsing. This method avoids the subgraph isomorphism judgment and selects the productions specifically, so that the time-complexity is greatly reduced.     

A modified tetramethylbenzidine method for measuring lipid hydroperoxides

A simple and sensitive spectrophotometric method for measuring lipid peroxides and peroxides in general is described. The method was developed by modifying an existing method based on the peroxidase activity of hemoglobin with tetramethylbenzidine as the electron donor. The modifications resulted in much improved sensitivity and reproducibility. With the modified method lipid peroxides as low as 2 nmol can be measured, a high sensitivity compared with other spectrophotometric methods. The absorbance is linear over a wide range of concentrations. It is suggested that this modified method in combination with the commonly used thiobarbituric acid method will give a better quantitation of lipid peroxidation.     

Curtis' Substitute for Van Gieson Stain

A triple staining method is described in which nuclear staining is by Weigert's hematoxylin. The cytoplasmic and collagen staining is effected by the Curtis substitute for Van Gieson, in which ponceau S is substituted for acid fuchsin. Nuclear staining is sharper than with Delafield's hematoxylin. The red of the collagen fibers is probably not subject to fading. Unlike Van Gieson, this method gives staining of reticular as well as collagen fibers. The advantages of the method are its simplicity and reliability. The use of this method is made possible by a new source of reliable samples of the ponceau S called for in this method.     

Mapping quantitative trait loci by an extension of the Haley-Knott regression method using estimating equations

The Haley-Knott (HK) regression method continues to be a popular approximation to standard interval mapping (IM) of quantitative trait loci (QTL) in experimental crosses. The HK method is favored for its dramatic reduction in computation time compared to the IM method, something that is particularly important in simultaneous searches for multiple interacting QTL. While the HK method often approximates the IM method well in estimating QTL effects and in power to detect QTL, it may perform poorly if, for example, there is strong epistasis between QTL or if QTL are linked. Also, it is well known that the estimation of the residual variance by the HK method is biased. Here, we present an extension of the HK method that uses estimating equations based on both means and variances. For normally distributed phenotypes this estimating equation (EE) method is more efficient than the HK method. Furthermore, computer simulations show that the EE method performs well for very different genetic models and data set structures, including nonnormal phenotype distributions, nonrandom missing data patterns, varying degrees of epistasis, and varying degrees of linkage between QTL. The EE method retains key qualities of the HK method such as computational speed and robustness against nonnormal phenotype distributions, while approximating the IM method better in terms of accuracy and precision of parameter estimates and power to detect QTL.     

啮齿动物的巢区面积估算法

巢区(Home range)是动物在其巢附近进行取食、生殖、育幼等日常活动的区域(Burt 1940)。标志流放法是应用最广的调查啮齿动物巢区的方法,尤其是按方格式布笼。但对同一野外调查结果,由于估算方法不同,巢区估算值相差很大,并且至今尚无学者提出一致公认的估算法。1980年5-10月,我们在青海省门源县的高寒草甸生态系统定位站调查根田鼠的巢区,按多种估算法对同一批实际调查结果估计了巢区面积,并对结果进行了分析比较,检查其特点和优缺点,并提出修正平均值法,作为我们今后讨论根田鼠巢区动态的基础。 对方格式布笼的调查结果进行巢区的估算方法,基本上分二大类,图形法和概率性模型法。图形法是按照捕点分布划出巢区,并直接求出巢区面积,如最小面积法,包括或不包括周边地带法,最大距离法和复合散布图法。     

Condition Number Estimation of Preconditioned Matrices

The present paper introduces a condition number estimation method for preconditioned matrices. The newly developed method provides reasonable results, while the conventional method which is based on the Lanczos connection gives meaningless results. The Lanczos connection based method provides the condition numbers of coefficient matrices of systems of linear equations with information obtained through the preconditioned conjugate gradient method. Estimating the condition number of preconditioned matrices is sometimes important when describing the effectiveness of new preconditionerers or selecting adequate preconditioners. Operating a preconditioner on a coefficient matrix is the simplest method of estimation. However, this is not possible for large-scale computing, especially if computation is performed on distributed memory parallel computers. This is because, the preconditioned matrices become dense, even if the original matrices are sparse. Although the Lanczos connection method can be used to calculate the condition number of preconditioned matrices, it is not considered to be applicable to large-scale problems because of its weakness with respect to numerical errors. Therefore, we have developed a robust and parallelizable method based on Hager’s method. The feasibility studies are curried out for the diagonal scaling preconditioner and the SSOR preconditioner with a diagonal matrix, a tri-daigonal matrix and Pei’s matrix. As a result, the Lanczos connection method contains around 10% error in the results even with a simple problem. On the other hand, the new method contains negligible errors. In addition, the newly developed method returns reasonable solutions when the Lanczos connection method fails with Pei’s matrix, and matrices generated with the finite element method.     

The office treatment of tattoos: a simple and effective method

A simplified method for the treatment of tattoos is described. The method is based on an older method called the "French method" known to tattoo artists. The treatment consists of superficial dermabrasion of the skin followed by application of a tannic acid solution which is then "rubbed" into the skin by the dermabrasion wheel. The treatment site is then "painted" with a silver nitrate stick. A heavy eschar forms which separates in approximately 2 to 3 weeks. The method incorporates the use of equipment that is present in the usual plastic surgical office. The method has produced excellent improvement in tattoos, with obliteration of the tattoo in the majority of cases. This report covers 85 patients with 207 tattoos treated over an 11-year period. The method is presented as a treatment of tattoos that are too large for simple excision. Details of the treatment are presented.     

酵母表达重组人血清白蛋白检测方法的比较

应用生化法、电泳扫描结合Bradford法、竞争ELISA等3种方法检测酵母表达重组人血清白蛋白(rHSA)的表达量。结果表明,3种方法检测结果近似。比较而言,生化法灵敏度较低,但操作简便,价格低廉;竞争ELISA法灵敏度最高,但需要特异的抗体;电泳扫描结合Bradford法需要特殊仪器,操作繁琐,花费时间长,灵敏度介于生化法和竞争ELISA法之间。综合利弊,生化法可作为检测酵母表达rHSA的首选方法,如条件允许,可考虑采用电泳扫描结合Bradford法或竞争EUSA。     

Preparation of single-stranded DNA from PCR products with streptavidin magnetic beads

The preparation of single-stranded DNA from double-stranded PCR products is an essential step in the identification of aptamers by Systematic Evolution of Ligands by EXponential enrichment (SELEX). The most widely used method for producing single-stranded DNA is alkaline denaturation of biotinylated PCR products attached to streptavidin-coated magnetic beads. Recently, it has been suggested that this method may be unsuitable due to the release of interfering amounts of streptavidin and biotinylated DNA. In this article, the alkaline method is compared with a thermal method that is known to release significant amounts of streptavidin and biotinylated DNA. Results show that trace amounts of streptavidin and biotinylated DNA are released in the alkaline method, but this can be curtailed by preconditioning the beads in aqueous sodium hydroxide. The main product in the alkaline method is single-stranded DNA, which is produced in high yield.     

滤膜法测定水中大肠菌群简便方法的研究

本研究方法为ＩＳＯ９３０８－１规定的滤膜法测定水中大肠菌群的方法,该方法操作简便只需分离和证实两步实验即可得出结果;分离培养基上的阴阳性菌落颜色分明,易于分辩;所用培养基不含致癌物质。本研究方法的准确度高,回收率的均值为９４７％,批内变异系数小于１０％,检出限为５００ｍｌ水样可检出１个ＣＦＵ,检出率是传统方法的３１倍。本研究还探讨了分离培养基的ｐＨ值对菌落颜色的影响。本研究内容经查新在国内尚无报道。     

A new method for isolation of polyamines from animal tissues

A new method for isolation of polyamines from tissues was developed and compared with the butanol extraction method which has been widely used for quantitative determination of polyamines. In the new method protein-free tissue extracts are applied to a small Dowex-50 column. The column is washed with appropriate buffers to remove ninhydrin-positive contaminants and the polyamines are eluted. With this method, the overall recovery of polyamines, after separation by paper electrophoresis and subsequent colorimetric determination with ninhydrin, is always over 90% (average 95%). This method is much better than the butanol method, which gives variable recoveries of 70–90%. The new method also has the advantages over the butanol method that the isolated polyamines are purer and the procedure is simpler.