A genetic algorithm on multiple sequences alignment problems in biology

The study and comparison of sequences of characters from a finite alphabet is relevant to various areas of science, notably molecular biology. The measurement of sequence similarity involves the consideration of the possible sequence alignments in order to find an optimal one for which the “distance” between sequences is minimum. In biology informatics area, it is a more important and difficult problem due to the long length (100 at least) of sequence, this cause the compute complexity and large memory require. By associating a path in a lattice to each alignment, a geometric insight can be brought into the problem of finding an optimal alignment, this give an obvious encoding of each path. This problem can be solved by applying genetic algorithm, which is more efficient than dynamic programming and hidden Markov model using commomly now. Foundation item: Supported by Zi-qiang Foundation of Wuhan University and Open Foundation of the State Key-Laboratory of Software Engineering, Wuhan University Biography: Shi Feng(1966-), male, Associate professor, research direction: bioinformatics.     

Identification of protein superfamily from structurebased sequence motif

The structure-based sequence motif of the distant proteins in evolution, protein tyrosine phosphatases (PTP) Ⅰ and Ⅱ superfamilies, as an example, has been defined by the structural comparison, structure-based sequence alignment and analyses on substitution patterns of residues in common sequence conserved regions. And the phosphatases Ⅰ and Ⅱ can be correctly identified together by the structure-based PTP sequence motif from SWISS-PROT and TrEBML databases. The results show that the correct rates of identification are over 98%. This is the first time to identify PTP Ⅰ and Ⅱ together by this motif.     

Occupant evacuation model based on cellular automata in fire

By applying the rules set in traffic flow and pedestrian flow models, a basic cellular automata model is presented to simulate occupant evacuation in fire. Some extended models are introduced to study the special phenomena of evacuation from the fire room. The key of the models is the introduction of the danger grade which makes the route choice convenient and reasonable. Fire not only influences the emotional and behavioral characteristics of an individual but also affects his physical constitution, which reduces his maximal possible velocity. The models consider these influence factors by applying a set of simple but effective rules. It is needed to emphasize that all rules are established according to the essential phenomenon in fire evacuation, that is, all the occupants would try to move to the safest place as fast as possible. Some simulation examples are also presented to validate the applicability of the models.     

Manipulation and cutting of carbon nanotubes

Nanomanipulation plays an important role in nanofabrication, it is also a technology necessary in exploring the secrets of nanoworld, and it thus beco mesa start point to research future nanomachine. In this study, manipulation and cutting of carbon nanotubes have been conducted in order to examine whether we can move a nanocomponent from one site to another by using the tip of atomic fo rce microscope (AFM). The technique may also be valuable for providing the const ructive materials of nanofabrication. While exploring the method for manipulatin g and cutting of nanotubes, some new phenomena have been observed during the process. Results show that carbon nanotubes present a feature of deformation combin ing bending and distortion when subjected to large mechanical forces exerted by the tip of AFM. In special cases, long carbon nanotubes can be cut into two part s, by which we can remove the part where crystal lattice is flawed, and therefor e a perfect nanocomponent can be obtained.     

Construction of human and mouse brain cDNA libraries and isolation of full-length cDNAs

cDNA libraries from aborted human 3-month fetal brain,adult rat and mouse brain were constructed by using a yZAP express cDNA library construction kin.Low molecular weight fragments of the second strand cDNASA were removed by flowing through the Sepharose CL-4B column and the frractionated long,Middle,Short fragments and the combined fragments weire respectively inserted into clone vectors to construct the cDNA libraries of the brain of human 3-month fetus.The 5'ends of 1200 clones from each of human fetal brain cDNA libraries were sequenced.A total of 894 ESTs were obtained and some full-length clones were squenced.By andalyaing the se-quences,12 novel full-length cDNAs were obtained.     

转杯纺自由纱段形态对其捻度分布的影响

通过对自由纱段的运动及受力分析，对自由纱段形态以及纺纱工艺参数对自由纱段捻度分布的影响进行了研究。研究表明：因自由纱段在杯内成弯曲形状，从而使得自由纱段捻度自假捻盘入口处向剥离点处不断减少，真至剥离点处纱条捻度甚至降到只有设计捻度的40%-80%。为了保证凝聚槽内一定的捻度传递长度，则须适当提高设计捻度，这就揭示了转杯纱设计捻度高于环锭纱的一个主要原因。高速细支时的剥离点纱条捻度相对于低速粗支而言要高，说明只要一些纺纱工艺参数如转杯直径、转杯速度、假捻盘规格等配合得当，转杯纺也可高速稳定地纺制细支纱。     

机器人系统中环境动力学模型及其参数辨识

根据机器人系统中环境的本质特征，本文提出了环境动力学既有刚体运动力学特性，又有表面开变动力学特性的观点；由此建立了新的环境动力学模型，给出了该动力学模型参数辨识的遗传算法模型，理论分析和实验研究表是该模型及其参数辨识方法是实用的，可行的。     

汞的生物毒性及其防治策略

汞是一种剧毒环境污染物。汞与生物大分子上的活性点结合,使其失去活性,导致病变。     

一类非线性反应扩散系统正解的存在性

利用上下解原理的方法，研究一类生态学中的反应扩散系统Volterra-Lotka模型的共生态。讨论了等出生率情形的互助模型正解的分歧结构，给出了正解的存在性，不存在性和惟一性条件。结果表明：对这类反应扩散方程组的理解依赖于对单个半线性椭圆方程的理解。     

主髂动脉硬化闭塞症的手术治疗

报道了48例主髂动脉闭塞症病人的手术治疗结果。行人造血管搭桥转流术31例，其中有8例同时行球囊导管扩张、动脉内膜剥成形或取栓术；导管动脉取栓扩张5例；动脉内膜剥脱、取栓3例；血管腔内支架置放9例。临床症状消失或好转42例，随访0.5-9年人造血血管通畅率90%。多普勒血流仪节段性测压踝/肱指数（ABI）对临床诊断、治疗和预后均有较高的价值，当ABI小于0.5时，应及时手术，挽救肢体，在确定治疗方案时，应根据病变部、分布和严重程度，施行不同的手术方法才能提高血管通畅率，得到良好的疗效。