• Title/Summary/Keyword: Defense mechanism

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Learning from the UK Disaster Management and Risk Assessment Systems (영국의 재난관리체계 및 재난위험성 평가제도의 도입 및 적용에 관한 연구)

  • Kim, Hak-Kyong;Kang, Wook
    • Korean Security Journal
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    • no.50
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    • pp.11-32
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    • 2017
  • The Civil Contingencies Act 2004 in the United Kingdom provides a comprehensive definition of "Emergency", calling upon the Uk's emergency management to deal with any disaster risk regardless of cause or source. Old contingency plans for civil defense and peacetime emergencies have been integrated into current integrated emergency management. In the UK, emergencies are managed by emergency services and other responders at the local level without direct involvement of central government. On top of this, a classified assessment of the risks of civil emergencies is also conducted on a regular basis, not only at the local level but also at the national level. This research looks into the Uk's emergency management system, including recent changes, and its risk assessment systems. Finally, the research draws policy implications for the development of Korea's disaster management mechanism as follows: 1) Korea should adopt an integrated emergency management system and combine civil defense with peacetime emergency planning, 2) it should create inter-operability between emergency responding organizations such as police, fire and ambulance, and finally 3) it must develop risk evaluating tools, such as a Community Risk Register and National Risk Register, both at the local and the national level. Last but not least, the UK emergency management system cannot be directly lifted from the UK and applied to risks and hazards faced by South Korea. Therefore, cross-cultural synthesis of many national approaches to emergency management is further required particularly for customizing policy to the particular needs of Korea.

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Identification and Molecular Characterization of Methionine Sulfoxide Reductase B Gene in Rice Blast Fungus, Magnaporthe oryzae (벼도열병균에서의 methionine sulfoxide reductase B 유전자의 분자적 특성)

  • Kim, Jeong-Hwan;Kim, Jin-Soo;Jeong, Mi-Yeon;Choi, Woo-Bong
    • Journal of Life Science
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    • v.19 no.3
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    • pp.343-348
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    • 2009
  • Magnaporthe oryzae, a major cause of rice blast, is one of the most destructive plant fungal pathogens. Secretion of reactive oxygen species (ROS) during the infection phase of plant pathogenic fungus plays a key role in the defense mechanism of a plant. ROS causes oxidative damage and functional modification to the proteins in a pathogenic fungus. Methionine, especially, is a major target of ROS, which oxidizes it to methionine sulfoxide. To survive from the attack of ROS, plant pathogenic fungus has antioxidative systems - one example would be methionine sulfoxide reductase B (MSRB), which reverses the oxidative alteration of methionine to methionine sulfoxide. In the present study, identification and molecular characterization of the MSRB gene in M. oryzae KJ201 were investigated. The MSRB gene was amplified by PCR from the M. oryzae KJ201 genomic DNA. The copy number of MSRB in the genome of M. oryzae KJ201 was identified by Southern blot analysis, which revealed that the gene exists as a single copy. To study the molecular function of an MSRB gene, the expression level of the MSRB gene was assayed with hydrogen peroxide treatment by Northern blot analysis and RT-PCR. The expression of the MSRB gene was increased by treatment of hydrogen peroxide, without significant correlation to hydrogen peroxide concentrations. These results indicate that the MSRB gene in M. oryzae KJ201 could contribute to protection against plant defense compounds such as ROS and offer a novel strategy for the control of rice blast.

Degradations of human immunoglobulins and hemoglobin by a 60 kDa cysteine proteinase of Trichomonas vaginalis (질편모충의 60 kDa 시스테인 단백분해효소의 인체 면역글로불린 및 헤모글로빈 분해능)

  • Duk-Young MIN;Keun-Hee Hyun;Jae-Sook Ryu;Myoung-Hee AHN;Myung-Hwan CHO
    • Parasites, Hosts and Diseases
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    • v.36 no.4
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    • pp.261-268
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    • 1998
  • The present study was undertaken to investigate the role of cysteine proteinase of Trichomonas vaginalis in escaping from host defense mechanism. A cysteine proteinase of T. vaginalis was purified by affinity chromatography and gel filtration. Optimum pH for the purified proteinase activity was 6.0. The proteinase was inhibited by cysteine and serine proteinase inhibitors such as E-64, NEM, IAA, leupeptin. TPCK and TLCK, and also by $Hg^{2+}$, but not affected by serine-, metallo-, and aspartic proteinase inhibitors such as PMSF, EDTA and pepstatin A. However, it was activated by the cysteine proteinase activator, DTT. The molecular weight of a purified proteinase was 62 kDa on gel filtration and 60 kDa on SDS-PAGE. Interestingly, the purified proteinase was able to degrade serum IgA, secretory IgA, and serum IgG in time- and dose-dependent manners. In addition, the enzyme also degraded hemoglobin in a dose-dependent manner. These results suggest that the acidic cysteine proteinase of T. vaginalis may play a dual role for parasite survival in conferring escape from host humoral defense by degradation of immunoglobulins, and in supplying nutrients to parasites by degradation of hemoglobin.

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Effect of the Ethanol Extract from Steamed Roots of Rehmannia Glutinosa on the Antioxidant Enzyme Activities in HEI-OC1 Auditory Cells (숙지황 에탄올 추출물이 HEI-OC1 세포의 항산화 효소 활성에 미치는 영향)

  • Yu Hyeon-Hee;Kim Yeon-Hwa;Jung Su-Young;Shin Mee-Kyung;Park Rae-Kil;So Hong-Seob;Jeon Byung-Hun;You Yong-Ouk
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.6
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    • pp.1557-1562
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    • 2005
  • A mechanism of hair cell damage caused by noise and ototoxic agents is mediated through generation of free radicals and reactive oxygen species (ROS). It is known that most of animals have defense systems to protect against ROS, and the cochlea of inner ear in animals also has ROS defense systems including several antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), and glutathione (GSH), which efficiently detoxifying ROS generated under normal condition. Steamed roots of Rehmannia glutinosa have been traditionally used in Oriental medicine for the treatment of auditory disease such as tinnitus, vertigo, and hearing loss as well as inflammatory diseases, hectic fever, night sweat, and headache. In the present study, we showed that the ethanol extract from steamed roots of R. giutinosa (ESRG) increased the antioxidant enzymes such as SOD, CAT, GPX, and GR activities and GSH level in HEI-OC1 auditory cells. This extract itself did not show any significant cytotoxicity up to $50{\mu}g/ml$. Our results further support the view that ESRG is promising sources of potential antioxidants. Future studies will be aimed at investigating the effects of ESRG on the regulation of cellular mechanisms and isolating and identifying the substances responsible for the regulation of antioxidant enzyme system from the plant extracts.

Grain Boundary Character Changes and IGA/PWSCC Behavior of Alloy 600 Material by Thermomechanical Treatment (가공열처리에 의한 Alloy 600 재료의 결정립계특성 변화와 입계부식 및 1차측 응력부식균열 거동)

  • Kim, J.;Han, J.H.;Lee, D.H.;Kim, Y.S.;Roh, H.S.;Kim, G.H.;Kim, J.S.
    • Korean Journal of Materials Research
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    • v.9 no.9
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    • pp.919-925
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    • 1999
  • Grain boundary characteristics and corrosion behavior of Alloy 600 material were investigated using the concept of grain boundary control by thermomechanical treatment(TMT). The grain boundary character distribution (GBCD) was analyzed by electron backscattered diffraction pattern. The effects of GBeD variation on intergranular at tack(JGA) and primary water stress corrosion cracking(PWSeC) were also evaluated. Changes in the fraction of coinci dence site lattice(CSL) boundaries in each cycle of TMT process were not distinguishable, but the total eSL boundary frequencies for TMT specimens increased about 10% compared with those of the commercial Alloy 600 material. It was found from IGA tests that the resistance to IGA was improved by TMT process. However, it was found from PWSCC test that repeating of TMT cycles resulted in the gradual decrease of the time to failure and the maximum load due to change in grain boundary characteristics, while the average crack propagation rate of primary crack increased mainly due to suppression of secondary crack propagation. It is considered that these corrosion characteristics in TMT specimens is attributed to 'fine tuning of grain boundary' mechanism.

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Investigation of ginsenosides in different tissues after elicitor treatment in Panax ginseng

  • Oh, Ji Yeon;Kim, Yu-Jin;Jang, Moon-Gi;Joo, Sung Chul;Kwon, Woo-Saeng;Kim, Se-Yeong;Jung, Seok-Kyu;Yang, Deok-Chun
    • Journal of Ginseng Research
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    • v.38 no.4
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    • pp.270-277
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    • 2014
  • Background: The effect of methyl jasmonate (MJ) on ginsenoside production in different organs of ginseng (Panax ginseng Meyer) was evaluated after the whole plant was dipped in an MJ-containing solution. MJ can induce the production of antioxidant defense genes and secondary metabolites in plants. In ginseng, MJ treatment in adventitious root resulted in the increase of dammarenediol synthase expression but a decrease of cycloartenol synthase expression, thereby enhancing ginsenoside biosynthesis. Although a previous study focused on the application of MJ to affect ginsenoside production in adventitious roots, we conducted our research on entire plants by evaluating the effect of exogenous MJ on ginsenoside production with the aim of obtaining new approaches to study ginsenoside biosynthesis response to MJ in vivo. Methods: Different parts of MJ-treated ginseng plants were analyzed for ginsenoside contents (fine root, root body, epidermis, rhizome, stem, and leaf) by high-performance liquid chromatography. Results: The total ginsenoside content of the ginseng root significantly increased after 2 d of MJ treatment compared with the control not subjected to MJ. Our results revealed that MJ treatment enhances ginsenoside production not in the epidermis but in the stele of the ginseng root, implying transportation of ginsenosides from the root vasculature to the epidermis. Application of MJ enhanced protopanaxadiol (PPD)-type ginsenosides, whereas chilling treatment induced protopanaxatriol (PPT)-type ginsenosides. Conclusion: These findings indicate that the production of PPD-type and PPT-type ginsenosides is differently affected by abiotic and biotic stresses in the ginseng plant, and they might play different defense mechanism roles.

Reliability Analysis of The Mission-Critical Engagement Control Computer Using Active Sparing Redundancy (ASR 기법을 적용한 임무지향 교전통제 컴퓨터의 신뢰도 분석)

  • Shin, Jin-Beom;Kim, Sang-Ha
    • The KIPS Transactions:PartA
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    • v.15A no.6
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    • pp.309-316
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    • 2008
  • The mission-critical engagement control computer for air defense has to maintain its operation without any fault for a long mission time. The mission performed by large-scale and complex embedded software is extremely critical in terms of dependability and safety of computer system, and it is very important that engagement control computer has high reliability. The engagement control computer was implemented using four processors. The distributed computer composed of four processors quarantees the dependability and safety, and ASR fault-tolerant technique applied to each processor guarantees the reliability. In this paper, the mechanism and performance of ASR fault-tolerant technique are analysed. And MTBF, reliability, availability, and cost-effectiveness for ASR, DMR and TMR techniques applied to the engagement control computer are analysed. The mission-critical engagement control computer using software-based ASR fault-tolerant technique provides high reliability and fast recovery time at a low cost. The mission reliability of the engagement control computer using ASR technique in 4 processors board is almost same the reliability of the computer using TMR technique in 6 processors board. ASR technique is most suitable to the mission-critical engagement control computer.

Biotic and Abiotic Factors Affecting Homoharringtonine Contents of Cephalotaxus koreana Nakai (개비자나무의 homoharringtonine 함량에 영향을 미치는 생물 및 무생물적 환경인자)

  • Jung, Myung-Suk;Hyun, Jung-Oh;Lee, Uk;Baik, Eul-Sun
    • Korean Journal of Plant Resources
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    • v.23 no.2
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    • pp.172-178
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    • 2010
  • This study was carried out to investigate abiotic and biotic environmental factors affecting homoharringtonine (HHT) contents of Cephalotaxus koreana, whereby, to provide basic information of high value-added industry production of HHT as a promising anti-cancer agent. For correlation between abiotic environmental factors (soil moisture, soil pH, habitat density and temperature) and HHT contents, the contents were highly correlated with soil moisture (0.77) and soil pH (-0.68). For multiple regression analysis of relationship between abiotic environmental factors (soil moisture and soil pH) and HHT contents, soil moisture appeared to be strongly affecting the contents relatively due to being significant at only its regression coefficient ($26.48^{***}$). For the effect of biotic environmental factors (damage index) affecting HHT contents, the contents was quadratic with equation of $H=278.23+1242D-398.87D^2$, also, damage index had strong effect on the contents. Finally, for the result of the most influencing an environmental factor on HHT contents, both damage index and soil moisture were suitable in second polynomial regression, also, damage index ($R^2=0.73^{***}$) was turned out to be more influencing factor than soil moisture ($R^2=0.67^{**}$) on HHT contents relatively. Therefore, we predict that HHT contents in the trees of Cephalotaxus koreana is produced as a chemical defense mechanism triggered by a stress-related damage of fungi or insects.

Efficient Poisoning Attack Defense Techniques Based on Data Augmentation (데이터 증강 기반의 효율적인 포이즈닝 공격 방어 기법)

  • So-Eun Jeon;Ji-Won Ock;Min-Jeong Kim;Sa-Ra Hong;Sae-Rom Park;Il-Gu Lee
    • Convergence Security Journal
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    • v.22 no.3
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    • pp.25-32
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    • 2022
  • Recently, the image processing industry has been activated as deep learning-based technology is introduced in the image recognition and detection field. With the development of deep learning technology, learning model vulnerabilities for adversarial attacks continue to be reported. However, studies on countermeasures against poisoning attacks that inject malicious data during learning are insufficient. The conventional countermeasure against poisoning attacks has a limitation in that it is necessary to perform a separate detection and removal operation by examining the training data each time. Therefore, in this paper, we propose a technique for reducing the attack success rate by applying modifications to the training data and inference data without a separate detection and removal process for the poison data. The One-shot kill poison attack, a clean label poison attack proposed in previous studies, was used as an attack model. The attack performance was confirmed by dividing it into a general attacker and an intelligent attacker according to the attacker's attack strategy. According to the experimental results, when the proposed defense mechanism is applied, the attack success rate can be reduced by up to 65% compared to the conventional method.

Effects of Banha Extract on the Melanin Biosynthesis and Tyrosinase mRNA Level in Bl6 Mouse Melanoma Cells (반하 추출물이 B-16 마우스 흑색종 세포의 멜라닌 생성과 타이로시네이즈 mRNA 양에 미치는 영향)

  • 이상화;김진준
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.23 no.2
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    • pp.23-32
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    • 1997
  • Melanin pigmentation in human skin is a major defense mechanism against ultraviolet light of the sun. Tyrosinase(EC 1.14.18.1) plays a key role in the biosynthesis of ultraviolet of melanin. This is why much researches have been focused on its regulation in controlling the epidermal melanization. We have found that the water-extract of Banha(Pinelliae ternate B.), an oriental medicinal plant, has no tyrosinase inhibitory activity, but does inhibit the melanin biolsynthesis in B16 mouse melanin cells. We also found that Banha extract lowers the tyrosinase activity in cultured cells. To elucidate the action mechanism of Banha extract we have investigated its effect on the tyrosinase mRNA level using reverse transcription-polymerase chain reaction technique. It was revealed that Banha extract reduced the tyrosinase mRNA level in dose dependent manner; when B16 mouse melanoma cells were cultured with 2mg/ml and 5mg/ml of Banha extract, there were 20% and 44% decrease in tyrosinase mRNA level, respectively. These data suggest that the Banha extract exerts its melanogenic inhibitory effect through the transcriptional regulation of tyrosinase mRNA.

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