• Title/Summary/Keyword: virus evolution

Search Result 68, Processing Time 0.03 seconds

Evolution of avian infectious bronchitis virus: Genetic drift and recombination

  • Lee, Chang-Won
    • Korean Journal of Veterinary Service
    • /
    • v.25 no.1
    • /
    • pp.97-103
    • /
    • 2002
  • Infectious bronchitis(IB) is a viral disease in which continued evolution of the virus is of paramount importance for annual endemics and epidemics in chickens. Since the isolation of IB viruses(IBVs) in the 1930s, over 50 serotypes or variants have been reported worldwide. Continuing evolution is most prominent in the suface glycoproteins of IBV but also occurs in other parts of the genome. This genetic variability results from accumulation of molecular changes that can occur by a number of different mechanisms including genetic drift (point mutations) and genetic shift(RNA recombination). GA98 is a new serotype of IBV identified recently in the United States. In this paper, the evolutionary trend of IBV will be discussed using GA98 serotype as a model.

Health monitoring sensor placement optimization for Canton Tower using virus monkey algorithm

  • Yi, Ting-Hua;Li, Hong-Nan;Zhang, Xu-Dong
    • Smart Structures and Systems
    • /
    • v.15 no.5
    • /
    • pp.1373-1392
    • /
    • 2015
  • Placing sensors at appropriate locations is an important task in the design of an efficient structural health monitoring (SHM) system for a large-scale civil structure. In this paper, a hybrid optimization algorithm called virus monkey algorithm (VMA) based on the virus theory of evolution is proposed to seek the optimal placement of sensors. Firstly, the dual-structure coding method is adopted instead of binary coding method to code the solution. Then, the VMA is designed to incorporate two populations, a monkey population and a virus population, enabling the horizontal propagation between the monkey and virus individuals and the vertical inheritance of monkey's position information from the previous to following position. Correspondingly, the monkey population in this paper is divided into the superior and inferior monkey populations, and the virus population is divided into the serious and slight virus populations. The serious virus is used to infect the inferior monkey to make it escape from the local optima, while the slight virus is adopted to infect the superior monkey to let it find a better result in the nearby area. This kind of novel virus infection operator enables the coevolution of monkey and virus populations. Finally, the effectiveness of the proposed VMA is demonstrated by designing the sensor network of the Canton Tower, the tallest TV Tower in China. Results show that innovations in the VMA proposed in this paper can improve the convergence of algorithm compared with the original monkey algorithm (MA).

Effects of Recombination on the Pathogenicity and Evolution of Pepper mottle virus

  • Jonson, Miranda Gilda;Seo, Jang-Kyun;Cho, Hong-Soo;Kim, Jeong-Soo;Kim, Kook-Hyung
    • The Plant Pathology Journal
    • /
    • v.25 no.4
    • /
    • pp.417-421
    • /
    • 2009
  • The analysis of the full length genome of Korean isolates of Pepper mottle virus (PepMoV) in previous study showed molecular variations and are found to be related to symptom variation and pathogenicity (Kim et al., 2009, Virus Res. 144:83-88). To fully understand the molecular variation of PepMoV in Korea, we further assessed the role of RNA recombination to biological variation and evolution of PepMoV. Full-length genome of a total of 17 Korean-PepMoV and 2 American (CA and FL) isolates were examined for possible detection of genetic recombination using different recombination detections programs and detected 5 and 8 tentative recombination events using RDP3 and Splits Tree4 programs, respectively. Interestingly, tentative recombinants detected such as isolates 57, 134 and 217 were previously identified as severe isolates and 205135 and 205136 as differentiating isolates (Kim et al., 2009, Virus Res. 144:83-88). In addition, recombination was frequently detected in the Vb isolate, the first PepMoV isolate reported in Korea, suggesting significant involvement in the evolution of PepMoV in Korea. These initial results of our recombination analyses among PepMoV isolates in Korea may serve as clues to further investigate the biological variations and evolution of PepMoV brought about by recombination.

Worm Virus Modeling and Simulation Methodology Using Artificial Life. (인공생명기반의 웜 바이러스 모델링 및 시뮬레이션 방법론)

  • Oh Ji-yeon;Chi Sung-do
    • Proceedings of the Korea Society for Simulation Conference
    • /
    • 2005.11a
    • /
    • pp.171-179
    • /
    • 2005
  • Computer virus modeling and simulation research has been conducted with focus on the network vulnerability analysis. However, computer virus generally shows the biological virus characters such as proliferation, reproduction and evolution. Therefore it is necessary to research the computer virus modeling and simulation using Artificial Life. The approach of computer modeling and simulation using the Artificial Life technology Provides the efficient analysis method for the effects on the network by computer virus and the behavioral mechanism of the computer virus. Hence this paper proposes the methodology of computer virus modeling and simulation using Artificial Life, which may be contribute the research on the computer virus vaccine.

  • PDF

A NON-MARKOVIAN EVOLUTION MODEL OF HIV POPULATION WITH BUNCHING BEHAVIOUR

  • Sridharan, V.;Jayshree, P.R.
    • Journal of applied mathematics & informatics
    • /
    • v.5 no.3
    • /
    • pp.785-796
    • /
    • 1998
  • In this paper we propose a model of HIv population through method of phases with non-Markovian evolution of immi-gration. The analysis leads to an explicit differnetial equations for the generating functions of the total population size. The detection process of antibodies (against the antigen of virus) is analysed and an explicit expression for the correlation functions are provided. A measure of bunching is also introduced for some particular choice of parameters.

Worm Virus Modeling and Simu1ation Methodology Using Artificial Life (인공생명 기반의 웜바이러스 모델링 및 시뮬레이선 방법론)

  • You, Yong-Jun;Chae, Soo-Hoan;Chi, Sung-Do;Oh, Ji-Yeon
    • Journal of the Korea Society for Simulation
    • /
    • v.15 no.4
    • /
    • pp.1-10
    • /
    • 2006
  • Computer virus modeling and simulation research has conducted with focus on the network vulnerability analysis. But computer virus shows the biological virus characters such as proliferation, reproduction and evolution. Therefore it is necessary to research the computer virus modeling and simulation using the Artificial life technique. The approach of computer modeling and simulation using Artificial life provides the analysis method about the effects on the network by computer virus and the behavior mechanism of computer virus. Hence this paper proposes the methodology of computer virus modeling and simulation using Artificial life, which is effected to contribute the research on the computer virus vaccine.

  • PDF

Survey of Garlic Virus Disease and phylogenetic Characterization of Garlic Viruses of the Genus Allexivirus Isolated in Korea

  • Koo, Bong-Jin;Kang, Sang-Cu;Chang, Moo-Ung
    • The Plant Pathology Journal
    • /
    • v.18 no.5
    • /
    • pp.237-243
    • /
    • 2002
  • A survey of virus infection in garlic plants cultivated in Korea was conducted for three years. Most virus-infected garlic plants (Allium sativum) showed typical symptoms on the leaves such as yellow mosaic, stripes, and distortion. Through immunosorbent electron micro-scopy and RT-PCR analysis, the complex mixtures of viruses including garlic viruses of the genus Allerivirus, gaylic strain of Leek yellow stripe virus of the genus Potyvirus, and Garlic latent virus of the genus Carlavirus were identified in the virus-infected garlic plants. Among these viruses, Allexivirus was the most frequently detect-ed in the regions surveyed. Using sets of differential primers for Allexivirus genomes, two members of the genus were amplified and sequenced from the purified viruses. The deduced amino acid sequences for the coat proteins and the nucleic acid binding proteins of two viruses showed high homologies to Garlic virus A (CarV-A) and Garlic virus D (GarV-D) of Allekivirus. This is the first report of GarV-A and GarV-D in Korea. This suggests that Allexivirus in gavlic plants in Korea was mixed and varied. Phylogenetic analyses showed that the genus Allexivirus was diversi(ied by the processes of accumulation and evolution of viruses in garlic plants due to the long period of repeated vegetative propagation.

A Proposal of GA Using Symbiotic Evolutionary Viruses and Its Virus Evaluation Techniques

  • Sakakura, Yoshiaki;Taniguchi, Noriyuki;Hoshino, Yukinobu;Kamei, Katsuari
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2003.09a
    • /
    • pp.679-682
    • /
    • 2003
  • In this paper, we propose a Genetic Algorithm (GA) using symbiotic evolutionary viruses. Our GA is based on both the building block hypothesis and the virus theory of evolution. The proposed GA aims to control a destruction of building blocks by discovering, keeping, and propagating of building blocks based on virus operation. Concretely, we prepare the group of individuals and the group of viruses. In our GA, the group of individuals searches solutions and the group of viruses searches building blocks. These searches done based on the symbiotic relation of both groups. Also, our GA has two types of virus evaluation techniques. One is that each virus is evaluated by the difference of the fitness of an individual between before and after infection of virus. Another is that all viruses aye evaluated by the difference of the fitness of an individual between before and after infection of all viruses. Furthermore, we applied the proposed GA to the minimum value search problem of a test function which has some local solutions far from the optimal solution. And, we discuss a difference of behaviors of the proposed GA based on each virus evaluation techniques.

  • PDF

Interpretation and Prospection of Influenza Virus through Swine-origin Influenza Virus (신종플루 바이러스를 통한 인플루엔자 바이러스의 해석 및 전망)

  • Chang, Kyung-Soo
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.42 no.1
    • /
    • pp.1-15
    • /
    • 2010
  • Swine influenza virus (SIV) or swine-origin influenza virus (S-OIV) is endemic in swine, and classified into influenza A and influenza C but not influenza B. Swine influenza A includes H1N1, H1N2, H3N1, H3N2 and H2N3 subtypes. Infection of SIV occurs in only swine and that of S-OIV is rare in human. What human can be infected with S-OIV is called as zoonotic swine flu. Pandemic 2009 swine influenza H1N1 virus (2009 H1N1) was emerged in Mexico, America and Canada and spread worldwide. The triple-reassortant H1N1 resulting from antigenic drift was contained with HA, NA and PB1 of human or swine influenza virus, PB2 and PA polymerase of avian influenza virus, and M, NP and NS of swine influenza virus, The 2009 H1N1 enables to transmit to human and swine. The symptoms and signs in human infected with 2009 H1N1 virus are fever, cough and sore throat, pneumonia as well as diarrhea and vomiting. Co-infection with other viruses and bacteria such as Streptococcus pneumoniae can occur high mortality in high-risk population. 2009 H1N1 virus was easily differentiated from seasonal flu by real time RT-PCR which contributed rapid and confirmed diagnosis. The 2009 H1N1 virus was treated with NA inhibitors such as oseltamivir (Tamiflu) and zanamivir (Relenza) but not with adamantanes such as amantadine and rimantadine. Evolution of influenza virus has continued in various hosts. Development of a more effective vaccine against influenza prototypes is needed to protect new influenza infection such as H5 and H7 subtypes to infect to multi-organ and cause high pathogenicity.

  • PDF