• Title/Summary/Keyword: Defense mechanism

Search Result 581, Processing Time 0.022 seconds

A Study of Program Execution Control based on Whitelist (화이트리스트 기반 프로그램 실행 통제 방안 연구)

  • Kim, Chang-hong;Choi, Dae-young;Yi, Jeong-hyun;Kim, Jong-bae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2014.10a
    • /
    • pp.346-349
    • /
    • 2014
  • Currently, the growing cyber threat continues, the damage caused by the evolution of malicious code incidents become more bigger. Such advanced attacks as APT using 'zero-day vulnerability' bring easy way to steal sensitive data or personal information. However it has a lot of limitation that the traditional ways of defense like 'access control' with blocking of application ports or signature base detection mechanism. This study is suggesting a way of controlling application activities focusing on keeping integrity of applications, authorization to running programs and changes of files of operating system by hardening of legitimate resources and programs based on 'white-listing' technology which analysis applications' behavior and its usage.

  • PDF

Molecular Perspectives of SARS-CoV-2: Pathology, Immune Evasion, and Therapeutic Interventions

  • Shah, Masaud;Woo, Hyun Goo
    • Molecules and Cells
    • /
    • v.44 no.6
    • /
    • pp.408-421
    • /
    • 2021
  • The outbreak of coronavirus disease 2019 (COVID-19) has not only affected human health but also diverted the focus of research and derailed the world economy over the past year. Recently, vaccination against COVID-19 has begun, but further studies on effective therapeutic agents are still needed. The severity of COVID-19 is attributable to several factors such as the dysfunctional host immune response manifested by uncontrolled viral replication, type I interferon suppression, and release of impaired cytokines by the infected resident and recruited cells. Due to the evolving pathophysiology and direct involvement of the host immune system in COVID-19, the use of immune-modulating drugs is still challenging. For the use of immune-modulating drugs in severe COVID-19, it is important to balance the fight between the aggravated immune system and suppression of immune defense against the virus that causes secondary infection. In addition, the interplaying events that occur during virus-host interactions, such as activation of the host immune system, immune evasion mechanism of the virus, and manifestation of different stages of COVID-19, are disjunctive and require thorough streamlining. This review provides an update on the immunotherapeutic interventions implemented to combat COVID-19 along with the understanding of molecular aspects of the immune evasion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which may provide opportunities to develop more effective and promising therapeutics.

Multi-functional Fighter Radar Scheduling Method for Interleaved Mode Operation of Airborne and Ground Target (전투기탑재 다기능 레이다의 공대공 및 공대지 동시 운용 모드를 위한 스케줄링 기법)

  • Kim, Do-Un;Lee, Woo-Cheol;Choi, Han-Lim;Park, Joontae;Park, Junehyune;Seo, JeongJik
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.49 no.7
    • /
    • pp.581-588
    • /
    • 2021
  • This paper deals with a beam scheduling method in fighter interleaving mode. Not only the priority of tasks but also operational requirements that air-to-ground and air-to-air search tasks should be executed alternatively are established to maximize high-quality of situational awareness. We propose a real-time heuristic beam scheduling method that is advanced from WMDD to satisfies the requirements. The proposed scheduling method is implemented in a simulation environment resembling the task processing mechanism and measurement model of a radar. Performance improvement in terms of task delay time is observed.

Nonstructural Protein of Severe Fever with Thrombocytopenia Syndrome Phlebovirus Inhibits TBK1 to Evade Interferon-Mediated Response

  • Lee, Jae Kyung;Shin, Ok Sarah
    • Journal of Microbiology and Biotechnology
    • /
    • v.31 no.2
    • /
    • pp.226-232
    • /
    • 2021
  • Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging phlebovirus of the Phenuiviridae family that has been circulating in the following Asian countries: Vietnam, Myanmar, Taiwan, China, Japan, and South Korea. Despite the increasing infection rates and relatively high mortality rate, there is limited information available regarding SFTSV pathogenesis. In addition, there are currently no vaccines or effective antiviral treatments available. Previous reports have shown that SFTSV suppresses the host immune response and its nonstructural proteins (NSs) function as an antagonist of type I interferon (IFN), whose induction is an essential part of the host defense system against viral infections. Given that SFTSV NSs suppress the innate immune response by inhibiting type I IFN, we investigated the mechanism utilized by SFTSV NSs to evade IFNmediated response. Our co-immunoprecipitation data suggest the interactions between NSs and retinoic acid inducible gene-I (RIG-I) or TANK binding kinase 1 (TBK1). Furthermore, confocal analysis indicates the ability of NSs to sequester RIG-I and related downstream molecules in the cytoplasmic structures called inclusion bodies (IBs). NSs are also capable of inhibiting TBK1-interferon regulatory factor 3 (IRF3) interaction, and therefore prevent the phosphorylation and nuclear translocation of IRF3 for the induction of type I IFN. The ability of SFTSV NSs to interact with and sequester TBK1 and IRF3 in IBs demonstrate an effective yet unique method utilized by SFTSV to evade and suppress host immunity.

Red ginseng (Panax ginseng Meyer) oil: A comprehensive review of extraction technologies, chemical composition, health benefits, molecular mechanisms, and safety

  • Truong, Van-Long;Jeong, Woo-Sik
    • Journal of Ginseng Research
    • /
    • v.46 no.2
    • /
    • pp.214-224
    • /
    • 2022
  • Red ginseng oil (RGO), rather than the conventional aqueous extract of red ginseng, has been receiving much attention due to accumulating evidence of its functional and pharmacological potential. In this review, we describe the key extraction technologies, chemical composition, potential health benefits, and safety of RGO. This review emphasizes the proposed molecular mechanisms by which RGO is involved in various bioactivities. RGO is mainly produced using organic solvents or supercritical fluid extraction, with the choice of method greatly affecting the yield and quality of the end products. RGO contains a high unsaturated fatty acid levels along with considerable amounts of lipophilic components such as phytosterols, tocopherols, and polyacetylenes. The beneficial health properties of RGO include cellular defense, antioxidation, anti-inflammation, anti-apoptosis, chemoprevention, hair growth promotion, and skin health improvement. We propose several molecular mechanisms and signaling pathways that underlie the bioactivity of RGO. In addition, RGO is regarded as safe and nontoxic. Further studies on RGO must focus on a deeper understanding of the underlying molecular mechanisms, composition-functionality relationship, and verification of the bioactivities of RGO in clinical models. This review may provide useful information in the development of RGO-based products in nutraceuticals, functional foods, and functional cosmetics.

The Study on the Performance Prediction of Precision Linear Shaped Charge Using Numerical Analysis Method (수치해석 기법을 이용한 정밀선상성형장약의 성능 예측에 관한 연구)

  • Lee, Sieun
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.25 no.3
    • /
    • pp.275-284
    • /
    • 2022
  • Linear Shaped Charge(LSC) is widely used as a separation system in the field of weapon system. However, there are some disadvantages that are charging lots of explosives due to lack of uniformity and having difficulties of the design of liner and explosives because of manufacturing process. In order to solve these problems, Precision Linear Shaped Charge(PLSC) that can design a liner independently and charge explosives uniformly has been developed. In this study, PLSC was designed to have a proper liner shape and amount of explosives, and the penetration test of PLSC with different stand-off distance from liner to target was conducted. On the basis of the penetration test results of PLSC, the numerical analysis method using AUTODYN was established and verified. The penetrative mechanism and characteristics of PLSC with targets of different materials was analyzed from experimental and numerical results.

Intermediate Node Mobility Management Technique by Real-Time Monitoring in CCN Environment (CCN 환경에서 실시간 모니터링에 의한 중간노드 이동성 관리 기법)

  • Ko, Seung-Beom;Kwon, Tae-Wook
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.17 no.5
    • /
    • pp.783-790
    • /
    • 2022
  • The development of SNS and video platforms provided an opportunity to explode the activation of content production and consumption. However, in the legacy system, due to the host-based location-oriented data transmission, there are inherent limitations in efficient operation and management. As an alternative to this, a Contents Centric Network (CCN) was studied. In this paper, when intermediate nodes located between the information provider and the information requester between the real-time streaming services in the CCN environment move or restrict their use, failure through monitoring of wireless reception strength to solve problems like disconnection of transmission quality at the information consumer. We propose a stable intermediate node management mechanism through active response before occurrence.

Protective Role of Corticosterone against Hydrogen Peroxide-Induced Neuronal Cell Death in SH-SY5Y Cells

  • Lee, Chan;Jang, Jung-Hee;Park, Gyu Hwan
    • Biomolecules & Therapeutics
    • /
    • v.30 no.6
    • /
    • pp.570-575
    • /
    • 2022
  • Stress breaks body balance, which can cause diverse physiological disorders and worsen preexisting diseases. However, recent studies have reported that controllable stress and overcoming from stress reinforce resilience to resist against more intense stress afterwards. In this study, we investigated the protective effect of corticosterone (CORT), a representative stress hormone against hydrogen peroxide (H2O2)-induced neuronal cell death and its underlying molecular mechanism in SH-SY5Y cells, a human neuroblastoma cell line. The decreased cell viability by H2O2 was effectively restored by the pretreatment with low concentration of CORT (0.03 μM for 72 h) in the cells. H2O2-increased expression of apoptotic markers such as PUMA and Bim was decreased by CORT pretreatment. Furthermore, pretreatment of CORT attenuated H2O2-mediated oxidative damages by upregulation of antioxidant enzymes via activation of nuclear factor erythroid 2-related factor 2 (Nrf2). These findings suggest that low concentration of CORT with eustressed condition enhances intracellular self-defense against H2O2-mediated oxidative cell death, suggesting a role of low concentration of CORT as one of key molecules for resilience and neuronal cell survival.

A LFU based on Real-time Producer Popularity in Concent Centric Networks (CCN에서 실시간 생성자 인기도 기반의 LFU 정책)

  • Choi, Jong-Hyun;Kwon, Tea-Wook
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.16 no.6
    • /
    • pp.1113-1120
    • /
    • 2021
  • Content Central Network (CCN) appeared to improve network efficiency by transforming IP-based network into content name-based network structures. Each router performs caching mechanism to improve network efficiency in the CCN. And the cache replacement policy applied to the CCN router is an important factor that determines the overall performance of the CCN. Therefore various studies has been done relating to cache replacement policy of the CCN. In this paper, we proposed a cache replacement policy that improves the limitations of the LFU policy. The proposal algorithm applies real-time producer popularity-based variables. And through experiments, we proved that the proposed policy shows a better cache hit ratio than existing policies.

An autopsy case of cerebral arterial thrombosis after vaccination with ChAdOx1 nCOV-19

  • Hyeji Yang;Jaeyoon Ha;Hyun Wook Kang
    • Journal of Medicine and Life Science
    • /
    • v.19 no.2
    • /
    • pp.74-77
    • /
    • 2022
  • We present a fatal case of cerebral arterial thrombosis after corona virus disease 19 (COVID-19) vaccination with ChAdOx1 nCOV-19. The deceased was a 63-year-old woman with no relevant medical history. She presented symptoms of nausea, fatigue, and headache immediately after vaccination. Ten days after vaccination, she suddenly started vomiting and developed high blood pressure. The patient eventually died 23 days after vaccination. Autopsy findings showed that the cerebral arteries and internal carotid arteries were fully enlarged and were compacted with thrombi. The brain stem showed ischemic necrosis, and extravasation from this necrotic lesion led to focal subarachnoid hemorrhage around the brain stem where large blood clots still remained. No aneurysms or atherosclerotic changes were found in these arteries. We note the following three facts. Firstly, all symptoms occurred immediately after vaccination; secondly, the main cause of death was consistent with known side effects of the vaccine; and lastly, the mechanism of thrombus formation in this case goes beyond the general category of thrombogenesis known so far. While the authors know that this case does not fall into known categories of vaccine side effects, we presenting this case to demonstrate that a comprehensive review of various possibilities related to vaccine side effects is needed to establish a COVID-19 defense system.