• Title/Summary/Keyword: Defense mechanism

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Design and Analyses of Security Mechanism with Low Cost RFID Tag (저비용 RFID 태그를 위한 보안 메카니즘의 분석 및 설계)

  • Kim, Jung-Tae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.681-682
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    • 2011
  • RFID technique has been applied in high-security and high-integrity settings such as national defense, healthcare, and citizen identification. We proposed especially the privacy of sensitive data, various cryptographic techniques applicable to low-cost RFIDs in order to enhance the security of RFID.

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Autophagy in neutrophils

  • Shrestha, Sanjeeb;Lee, Jae Man;Hong, Chang-Won
    • The Korean Journal of Physiology and Pharmacology
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    • v.24 no.1
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    • pp.1-10
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    • 2020
  • Autophagy is a highly conserved intracellular degradation and energy-recycling mechanism that contributes to the maintenance of cellular homeostasis. Extensive researches over the past decades have defined the role of autophagy innate immune cells. In this review, we describe the current state of knowledge regarding the role of autophagy in neutrophil biology and a picture of molecular mechanism underlying autophagy in neutrophils. Neutrophils are professional phagocytes that comprise the first line of defense against pathogen. Autophagy machineries are highly conserved in neutrophils. Autophagy is not only involved in generalized function of neutrophils such as differentiation in bone marrow but also plays crucial role effector functions of neutrophils such as granule formation, degranulation, neutrophil extracellular traps release, cytokine production, bactericidal activity and controlling inflammation. This review outlines the current understanding of autophagy in neutrophils and provides insight towards identification of novel therapeutics targeting autophagy in neutrophils.

The Road to RNA Silencing is Paved with Plant-Virus Interactions

  • Palukaitis, Peter
    • The Plant Pathology Journal
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    • v.27 no.3
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    • pp.197-206
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    • 2011
  • RNA silencing has had a large impact on biology in general, as well as on our understanding of plant-pathogen interactions, especially interactions between plants and viruses. While most of what we know about the mechanism of RNA silencing was deduced in the last 12 years, many of the interactions between plants and viruses, as well as virus-virus interactions in plants, which we now know are manifestations of RNA silencing, were the subject of decades of work from numerous laboratories. These laboratories were examining the nature and extent of phenomena such as recovery from infection, the formation of dark green islands resistant to re-infection, synergy between unrelated viruses and cross-protection between related viruses, all first described in the late 1920s. In this review, the relationships between these phenomena and their place in the defense mechanism we call RNA silencing will be described, to show how they are all linked.

Beyond Viral Interferon Regulatory Factors: Immune Evasion Strategies

  • Myoung, Jinjong;Lee, Shin-Ae;Lee, Hye-Ra
    • Journal of Microbiology and Biotechnology
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    • v.29 no.12
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    • pp.1873-1881
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    • 2019
  • The innate immune response serves as a first-line-of-defense mechanism for a host against viral infection. Viruses must therefore subvert this anti-viral response in order to establish an efficient life cycle. In line with this fact, Kaposi's sarcoma-associated herpesvirus (KSHV) encodes numerous genes that function as immunomodulatory proteins to antagonize the host immune system. One such mechanism through which KSHV evades the host immunity is by encoding a viral homolog of cellular interferon (IFN) regulatory factors (IRFs), known as vIRFs. Herein, we summarize recent advances in the study of the immunomodulatory strategies of KSHV vIRFs and their effects on KSHV-associated pathogenesis.

Gas-Forming Brain Abscess Caused by Klebsiella Pneumoniae

  • Cho, Keun-Tae;Park, Bong-Jin
    • Journal of Korean Neurosurgical Society
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    • v.44 no.6
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    • pp.382-384
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    • 2008
  • Gas forming brain abscess is a rare disease caused by Klebsiella pneumoniae occurring in patients with impaired host defense mechanism such as diabetes mellitus or liver cirrhosis. A 59-year-old man with 2-year history of diabetes mellitus and 20-year history of liver cirrhosis presented to the hospital with headache. On the day after admission, severe headache was developed and he deteriorated rapidly. Brain CT showed a non-enhanced mass including multiple air density as well as surrounding edema seen in the right occipital lobe, and isodensity air-fluid level seen in the right lateral ventricle. Despite emergent ventricular drainage and intraventricular and intravenous administration of antibiotics, his condition progressively worsened to sepsis and to death after 5 days. Bacterial culture of blood and ventricular fluids disclosed a Gram (-) rod, Klebsiella pneumoniae. In this report we review the pathogenic mechanism and its management.

A Study on Dispersed Media Formation of Hydrocarbon Fuel by an Explosive Burster (화약 폭발에 의한 탄화수소계 연료의 분산매질 형성에 관한 연구)

  • Yoo, Jae Hun
    • Journal of the Korean Society of Safety
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    • v.31 no.2
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    • pp.33-40
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    • 2016
  • Liquid fuel can be easily exploded and release more energy of detonation than conventional explosives because it has different explosion mechanism. In order to analyze dispersion characteristics of liquid fuel for the safety purpose, two tests are conducted. First, pre-test, which is a computer simulation, is carried out by a software called ANSYS AUTODYN to eliminate the effect of a canister that usually causes irregular dispersion of the fuel. Second, field test is performed to find out the amount and density effect of bursting charge. High speed cameras are installed in front of the canister to visualize the mechanism. Velocity, area and radius of the dispersed cloud are measured by image processing software, these are shown that the amount of bursting charge affects cloud velocity and area but density is not a significant factor of cloud formation.

A Study on the Security Vulnerabilities and Defense Mechanism for SET-based Electronic Commerce (SET기반 전자상거래의 보안위협요소 분석 및 대응 방안에 관한 연구)

  • 김상균;강성호
    • The Journal of Society for e-Business Studies
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    • v.4 no.2
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    • pp.59-79
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    • 1999
  • In order to construct a successful electronic commerce system, three main essential factors must be satisfied to obtain the best effective outcomes. The three main essential factors are as follows : economic factor, effectiveness factor and convenient factor. In order to understand the role of these three factors, one must have some insight knowledge about security to assist him to implement these three factors in his construction of an electronic commerce system. This paper analyses a implementation mechanism of security systems based on the SET 1.0 standard for electronic commerce systems, thus providing an effective plan for the construction of a security system in the SET-based electronic commerce field. This paper helps to analyse the elements of security vulnerabilities in the SET 1.0 standard implementation and also helps to understand the SET 1.0 protocol.

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Immunity and asthma: friend or foe?

  • Mehta, Anita;Gohil, Priyanshee
    • Advances in Traditional Medicine
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    • v.8 no.1
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    • pp.1-16
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    • 2008
  • Immunity is responsible for the defense mechanism of the body but in case of autoimmune diseases, its role gets diverted. Like so many other diseases, asthma is also considered as one of the most common autoimmune diseases to be occurring in community. Asthma is defined as a chronic inflammatory airway disease that is characterized by airway hyper reactivity and mucus hypersecretion that result in intermittent airway obstruction. The incidence of allergic asthma has almost doubled in the past two decades. Although, precise causative mechanism of asthma is unknown, but several mechanisms have been proposed that is immunological, pharmacological and genetic mechanisms, and airway and neurogenic inflammation. The inflammatory process observed in the asthmatic patients is the final result of a complex network of interactions between various immunological cell lineages, its mediators and secreted substances. Thus, among the mechanisms proposed, the immunological one plays a key role. Through this article, we have tried to provide some insight into immunological mechanisms in pathogenesis of asthma.

The Mechanism of Poly I:C-Induced Antiviral Activity in Peritoneal Macrophage

  • Pyo, Suh-Kenung
    • Archives of Pharmacal Research
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    • v.17 no.2
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    • pp.93-99
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    • 1994
  • Macrtophages play an important role in defense against virus infection by intrinsic resistance and by extrinsic resistance. Since interferon-induced enzymes which are 2'-5' oligoadenylate synthetase and p1/eIF-2 protein kinase have been shown to be involved in the inhibition of viral replication, I examined the mechanism by which poly I:C, an interferon inducer, exerts its antiviral effects in inflammatory macrophages infected with herpes simplex virus type 1 (HSV-1). The data presented here demonstrate that poly I:C-induced antiviral activity is partially due to the activation of 2'-5' pligoadenylate synthetase. The activation of 2'-5' oligoadenlate A synthetase by poly I:C is also at least mediated via the production of interferon-.betha.. Taken together, these data indicate that interferon-.betha. produced in response to poly I:C acts in an autocrine manner to activate the 2'-5' oligoadenylate synthetase and to induce resistance to HSV-1.

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Strengthening Mechanism of the Ni3Al-based Alloy (Ni3Al계 합금의 강화기구)

  • Han, Chang-Suk
    • Korean Journal of Metals and Materials
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    • v.49 no.2
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    • pp.137-144
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    • 2011
  • Strengthening mechanisms in an ordered intermetallic compound containing coherent precipitates of lower antiphase boundary energy than the matrix were investigated on the basis of the interaction between the deformation induced dislocations and the disordered precipitates in an $Ll_2$ ordered $Ni_3Al$-based alloy. Extra work was needed to pull out the dislocations from the precipitate, which was dependent on the difference in the antiphase boundary energy between the matrix and the precipitate, as well as the size and volume fraction of the precipitate. The strength of the $Ll_2$ ordered ${\gamma}^{\prime}$ phase containing fine precipitates of the disordered ${\gamma}$ phase was examined using the proposed model. The model can explain almost quantitatively the age hardening behavior of the $Ll_2$ ordered ${\gamma}^{\prime}$ phase.