Adaptive Quantile Estimation and its Application in Analysis of Biological Signals

Quantiles and their estimations are the basis for solving numerous problems of statistics. The paper presents adaptive recursive estimation methods for this statistical parameter. Its specifical properties are investigated and the possibilities of applications in computer assisted analysis of biological signals are demonstrated even satisfying real time requirements.     

Estimation of multiple biomass growth rates and biomass concentration in a class of bioprocesses

In this paper, an approach to the estimation of multiple biomass growth rates and biomass concentration is proposed for a class of aerobic bioprocesses characterized by on-line measurements of dissolved oxygen and carbon dioxide concentrations, as well as off-line measurements of biomass concentration. The approach is based on adaptive observer theory and includes two steps. In the first step, an adaptive estimator of two out of three biomass growth rates is designed. In the second step, the third biomass growth rate and the biomass concentration are estimated, using two different adaptive estimators. One of them is based on on-line measurements of dissolved oxygen concentration and off-line measurement of biomass concentrations, while the other needs only on-line measurements of the carbon dioxide concentration. Simulations demonstrated good performance of the proposed estimators under continuous and batch-fed conditions.     

蛇毒检测技术研究进展

介绍了放射免疫测定法,凝集测定法,免疫电泳检测,荧光免疫测定法,酶联免疫吸附测定法和生物传感器检测方法在蛇毒检测中的应用,并比较了各种方法的优点和不足。     

猪链球菌毒力因子和鉴定方法的研究进展

猪链球菌(Streptococcus suis)是一种重要的人畜共患病病原体,能够引起猪疫病,人类感染该菌可导致脑膜炎、败血症甚至死亡。鉴于其对养猪业的巨大经济影响和对公共卫生事业的威胁,关于猪链球菌的研究日益深入,即对其毒力相关蛋白和鉴定方法的研究进展做一综述。     

应用不同方法检测食品中大肠菌群结果的比较

评价检测食品中大肠菌群不同方法。比较国家标准、行业标准和显色培养基检测方法检测大肠菌群结果的差别。国家标准和行业标准检测结果基本一致,但有差异,应用显色培养基检测大肠菌群优于目前使用的国家标准和出口食品检验行业标准方法。检测食品中大肠菌群,显色培养基检测方法快速、灵敏、特异。     

细菌c-di-AMP检测方法的研究进展

环二腺苷酸(cyclic diadenylate monophosphate,c-di-AMP)是一种广泛存在于细菌中的重要核苷酸第二信使分子,在病原体细菌,尤其是许多革兰阴性细菌中发挥着重要作用.研究表明,c-di-AMP在细菌生长、耐药性、抗应激、侵袭力和生物膜形成等方面担当不可取代的角色,同时参与激活和调节宿主的...     

Gene Conversion Among Paralogs Results in Moderate False Detection of Positive Selection Using Likelihood Methods

Previous studies have shown that recombination between allelic sequences can cause likelihood-based methods for detecting positive selection to produce many false-positive results. In this article, we use simulations to study the impact of nonallelic gene conversion on the specificity of PAML to detect positive selection among gene duplicates. Our results show that, as expected, gene conversion leads to higher rates of false-positive results, although only moderately. These rates increase with the genetic distance between sequences, the length of converted tracts, and when no outgroup sequences are included in the analysis. We also find that branch-site models will incorrectly identify unconverted sequences as the targets of positive selection when their close paralogs are converted. Bayesian prediction of sites undergoing adaptive evolution implemented in PAML is affected by conversion, albeit in a less straightforward way. Our work suggests that particular attention should be devoted to the evolutionary analysis of recent duplicates that may have experienced gene conversion because they may provide false signals of positive selection. Fortunately, these results also imply that those cases most susceptible to false-positive results—i.e., high divergence between paralogs, long conversion tracts—are also the cases where detecting gene conversion is the easiest. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

自适应蚁群算法在DNA中的应用

主要讨论了自适应蚁群算法在DNA序列比对中的应用，主要的过程是：首先，我们设一个计分函数和一个得分策略，在任意给出一对DNA序列，建立一个序列比对矩阵．现由4只蚂蚁从左上角向右下角移动，并且最终到达右下角，那么这4只蚂蚁随意走出4条路径，根据4条路径得出4对等长的比对，再依照计分函数分别计算出4条路径的比对得分，再由1．3式进一步验证4条路径的平均得分值，取其中得分最高（即最优路径）路径；进行第二次信息素增量的调整，方法是根据蚂蚁所走过的方向和该方向上得分比例计算出来的，信息素的变化量利用矩阵来存储，那么下一次蚂蚁所选的路径就要根据以前在各条路径上的信息素浓度总和的大小选择移动方向，最终经过有限次迭代，蚂蚁就会找到一条最优路径，也就是一条与原来DNA最相似的DNA链．     

抗体药物糖化检测方法及其生物学功能研究进展

糖化是一个重要的蛋白质修饰过程,可能影响治疗性蛋白药物（如单克隆抗体药物）的生物活性及分子稳定性。许多研究表明糖化血红蛋白水平升高与心血管疾病及动脉粥样硬化有着密切关系。人体的血浆蛋白,如白蛋白、球蛋白、纤维蛋白和胶原蛋白也可能被糖化,进而形成AGEs,蛋白药物的生产、储存以及药物在体内循环过程中都可能发生糖化反应。综述了治疗性抗体药物糖化的原因、分析方法,以及糖化对抗体药物生物学功能的影响,以期为临床抗体药物的开发、优化及贮存条件研究提供参考。     

分子生物学方法在食品微生物检测中的应用

近年来,食品安全受到广泛关注。及时、准确地检测出食品中的病原微生物是食品安全检测的重要内容,食品病原微生物的分子生物学检测技术因其特异性和灵敏性而备受瞩目。我们主要介绍了基因探针检测法、PCR检测法和基因芯片检测法的原理、开发及其在食品微生物检测中的应用。     

灰霉病菌抗药位点及其分子检测方法研究进展

灰霉病由灰葡萄孢侵染所致,化学防治是目前最常用的治理方法,而随着杀菌剂的广泛使用,抗药菌株频繁出现。本文就近年来已研究报道的灰葡萄孢菌的抗药分子位点进行了系统总结,包括六大类杀菌剂,涉及5个基因;对灰霉病菌抗药位点的分子检测方法进行了综述,包括测序法、CAPS、ARMS、Tetra primer ARMS-PCR、AS real-time PCR、ASPPAA PCR和双杂交探针法,通过对不同检测方法进行比较分析,指出现有技术存在的问题并展望未来高通量的检测方法的发展方向。     

排序法在植物群落与环境关系研究中的应用述评

自然环境对植物的影响主要表现在气候、水文、土壤及地形方面。大尺度上,气候类型明显影响植物的带状分布与物种空间格局;中小尺度上,土壤、水文、地形以及三者的交互作用影响植物生长必需的环境与资源条件,并对植物群落物种多样性起决定性作用。多元数量分析是研究植物群落生态关系的重要方法,在揭示植物群落与环境关系方面起到关键作用。排序法作为数量分析的重要手段,经常在植物生态学研究中扮演重要角色,尤其是在植物群落分布以及群落结构方面的应用已形成一种趋势。主要从植物群落分布以及群落结构的角度综述了当今排序法的应用,分析了面临的主要问题,并提出了未来可能发展方向,以期为今后排序方法的选择应用提供参考。     

Methods for Detection and Quantification of Polyphosphate and Polyphosphate Accumulating Microorganisms in Aquatic Sediments

It has been speculated that the microbial P pool is highly variable in the uppermost layer of various aquatic sediments, especially when an excessive P accumulation in form of polyphosphate (Poly‐P) occurs. Poly‐P storage is a universal feature of many different organisms and has been technically optimised in wastewater treatment plants (WWTP) with enhanced biological phosphorus removal (EBPR). In the recent past, new insights into mechanisms of P elimination in WWTP almost exclusively depended on the development and application of novel methods like ³¹P‐NMR spectroscopy and molecular methods for identifying Poly‐P accumulating microorganisms (PAO). The aim of the present review is to compile current methods potentially available for detection and quantification of Poly‐P in sediments and to complement it with yet unpublished results to validate their application in natural sediments. The most powerful tool for reliable Poly‐P quantification in sediments is the liquid ³¹P‐NMR technique which has been successfully used for Poly‐P measurements in a variety of aquatic sediments. But the microorganisms as well as mechanisms involved in Poly‐P storage and cycling are largely unknown. Therefore, we also intend to stimulate future studies focusing on these encouraging topics in sediment research via the implementation of novel methods. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Methods for Analysis of Protein Glutathionylation and their Application to Photosynthetic Organisms

Protein S-glutathionylation, the reversible formation of a mixed-disulfide between glutathione and protein thiols, is involved in protection of protein cysteines from irreversible oxidation, but also in protein redox regulation. Recent studies have implicated S-glutathionylation as a cellular response to oxidative/nitrosative stress, likely playing an important role in signaling. Considering the potential importance of glutathionylation, a number of methods have been developed for identifying proteins undergoing glutathionylation. These methods, ranging from analysis of purified proteins in vitro to large-scale proteomic analyses in vivo, allowed identification of nearly 200 targets in mammals. By contrast, the number of known glutathionylated proteins is more limited in photosynthetic organisms, although they are severely exposed to oxidative stress. The aim of this review is to detail the methods available for identification and analysis of glutathionylated proteins in vivo and in vitro. The advantages and drawbacks of each technique will be discussed as well as their application to photosynthetic organisms. Furthermore, an overview of known glutathionylated proteins in photosynthetic organisms is provided and the physiological importance of this post-translational modification is discussed.     

Comparison of Methods for Detection of Erysipelothrix spp. and Their Distribution in Some Australasian Seafoods

For many years, Erysipelothrix rhusiopathiae has been known to be the causative agent of the occupationally related infection erysipeloid. A survey of the distribution of Erysipelothrix spp. in 19 Australasian seafoods was conducted, and methodologies for the detection of Erysipelothrix spp. were evaluated. Twenty-one Erysipelothrix spp. were isolated from 52 seafood parts. Primary isolation of Erysipelothrix spp. was most efficiently achieved with brain heart infusion broth enrichment followed by subculture onto a selective brain heart infusion agar containing kanamycin, neomycin, and vancomycin after 48 h of incubation. Selective tryptic soy broth, with 48 h of incubation, was the best culture method for the detection of Erysipelothrix spp. with PCR. PCR detection was 50% more sensitive than culture. E. rhusiopathiae was isolated from a variety of different fish, cephalopods, and crustaceans, including a Western rock lobster (Panulirus cygnus). There was no significant correlation between the origin of the seafoods tested and the distribution of E. rhusiopathiae. An organism indistinguishable from Erysipelothrix tonsillarum was isolated for the first time from an Australian oyster and a silver bream. Overall, Erysipelothrix spp. were widely distributed in Australasian seafoods, illustrating the potential for erysipeloid-like infections in fishermen.     

实时荧光定量PCR及其在传染性疾病检测中的应用

实时荧光定量PCR技术被广泛应用于实验研究、临床检测中。与普通的PCR相比,实时荧光定量PCR技术具有特异性强、灵敏度高、重复性好、定量准确、速度快、全封闭反应等优点。我们综述了实时荧光定量PCR技术的原理、定量方法,及其在传染性疾病检测研究中的应用。     

凤尾蕨科旱生蕨类rbcL基因的适应性进化和共进化分析

核酮糖-1,5-二磷酸羧化酶/加氧酶（Rubisco,EC 4.1.1.39）是植物参与光合作用的关键酶,其大亚基由叶绿体rbcL基因编码。为深入理解凤尾蕨科植物对干旱生境的分子适应机制,本研究以53种凤尾蕨科旱生植物的rbcL基因为对象,展开适应性进化和共进化研究。采用位点间可变ω比值模型以及SLAC、REL和FEL等方法进行的适应性进化分析显示：在氨基酸水平上共有15个正选择位点（66S、84E、139L、235G、245I、252A、273Y、295K、296N、299M、307G、330E、349S、365F、404A）,其中位点245I、252A和273Y对维持Rubisco功能起重要作用。共进化分析共鉴定出2组共进化位点,分别由139L、273Y、295K和273Y、295K、349S组成,这些氨基酸位点间的共进化方式与蛋白质的疏水性和分子量都显著相关。以上结果一方面支持基于ω比值检验DNA编码序列发生适应性进化的有效性,另一方面也提示凤尾蕨科植物对干旱生境的适应可能与rbcL基因的适应性进化有关。     

两种教学方法在护理专业人体形态学教学中的应用及比较

目的:探讨A和B两神教学方法在护理专业人体形态学教学中的应用及比较.方法:通过应用A和B两种教学法,对全日制护理学专科2010-2班和护理学专科2011-2班的人体形态学期末考试平均成绩和及格率进行比较和分析.结果:采用A教学法的护理学专科2011-2班的最高分为88分,最低分为42,平均成绩为75.45分,标准差为10.34.采用B教学法的护理学专科2010-2班的最高分为84分,最低分为36,平均成绩为64.34分,标准差为11.65.对护理学专科2011-2班和2010-2班的平均成绩进行F检验,F=1.12＜1.50,故P＞0.10,方差齐,敌可用方差相等情形的两样本t检验,t=5.36＞2.66,故P＜0.01,两组平均成绩之间差异有统计学意义;采用A教学法的护理学专科2011-2班的及格率为81.54％,采用B教学法的护理学专科2010-2班的及格率为65.15％.对于以上两个班及格率进行卡方检验,x=4.49＞3.84,故P＜0.05,两组及格率之间差异有统计学意义.以上结果说明采用A教学法的护理学专科2011-2班的平均成绩和及格率明显高于采用B教学法的护理学专科2010-2班.结论:在人体形态学教学中,A教学法跟B教学法比具有明显的优势,同时A教学法自身也有不足之处.