• Title/Summary/Keyword: BMV

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Short-Term Viral Evolution in Response to Passaging I. Consequences for Population Size

  • Park, Gyung-Soon;Steven E. Kelley;Hing, Jung-Lim
    • 한국생태학회:학술대회논문집
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    • 2002.08a
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    • pp.83-91
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    • 2002
  • The Red Queen hypothesis for the advantage of sex predicts that pathogens will evolve by increasing fitness with frequent encounters with specific host genotypes. In this study, BMV population size, measured as an indicator of fitness, was investigated during repeated passages through the same, or different host genotypes of the crop host, Hordeum vulgare (barley). Overall, mean BMV concentration within individual hosts was significantly higher in genetically homogeneous compared to heterogeneous host passage lines. In addition, BMV populations, passaged through a specific host variety, showed higher growth in that host variety compared to BMV passaged through varying varieties. These results supports the Red Queen hypothesis. However, the decrease in viral populations during passages contradicts the Red Queen. Nevertheless, the results found here show that even under simplified conditions, pathogens do not evolve in simple, predictable ways. Constraints on pathogen evolution may lead to counterintuitive results.

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Short-Term Viral Evolution in Response to Passaging I. Consequences for Population Size

  • Park, Gyung-Soon;Kelley, Steven E.;Hong, Jung-Lim
    • The Korean Journal of Ecology
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    • v.25 no.4
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    • pp.217-225
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    • 2002
  • The Red Queen hypothesis for the advantage of sex predicts that pathogens will evolve by increasing fitness with frequent encounters with specific host genotypes. In this study, BMV population size, measured as an indicator of fitness, was investigated during repeated passages through the same, or different host genotypes of the crop host, Hordeum vulgare (barley). Overall, mean BMV concentration within individual hosts was significantly higher in genetically homogeneous compared to heterogeneous host passage lines. In addition, BMV populations, passaged through a specific host variety, showed higher growth in that host variety compared to BMV passaged through varying varieties. These results supports the Red Queen hypothesis. However, the decrease in viral populations during passages contradicts the Red Queen. Nevertheless, the results found here show that even under simplified conditions, pathogens do not evolve in simple, predictable ways. Constraints on pathogen evolution may lead to counterintuitive results.

A Study on the Native Environment and Cutting Propagation for the Black-berry Magnolia Vine [Schisandra repanda (Siebold & Zucc.) Radlk] in Halla Mountain (한라산 흑오미자의 자생환경 및 삽목증식 연구)

  • Boo, Jae Yoon;Kim, Ju Sung
    • Korean Journal of Medicinal Crop Science
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    • v.28 no.5
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    • pp.354-359
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    • 2020
  • Background: The recent, decline in Black-berry Magnolia Vine (Schisandra repanda; BMV) native to Jeju Island, Korea, has raised concerns about the causes of this decline. We investigated the native environment of S. repanda and evaluated its propagation through cuttings to provide preliminary data for its restoration in Jeju Island. Methods and Results: The native environment of the BMV in the Hallasan National Park was surveyed and the climatic variables (temperature and humidity) were analyzed. The effects of the sex of the donor plant (male/female) type of cutting (softwood/hardwood), and treatment with a plant growth regulator (indole-3-butylic acid/rootone) on the rooting of BMV were investigated. Additinallly, the rooting rate, root count, and root length, as well as temperature and humidity were measured in the vinyl moist chambers. BMV was observed in 63 plants distributed from 567 m to 1,364 m above sea level of the Hallasan National Park. In the cutting experiment, the rooting rate was 71.9%, and it was higer in female plants (75.0%) than in male plants (68.8%). Conclusions: The mass propagation of BMV through cuttings valuable for its restoration as without such safeguard measures, the population could face extinction within a few decades.

Comparison of compression pause time between different rescue ventilation maneuvers in two-rescuer cardiopulmonary resuscitation (2인구조자 심폐소생술 시 환기방법에 따른 가슴압박 중단시간의 비교: 일개 대학병원 간호사를 대상으로)

  • Hyun, Kwang-Rok;Moon, Jun-Dong
    • The Korean Journal of Emergency Medical Services
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    • v.19 no.2
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    • pp.7-17
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    • 2015
  • Purpose: This study aimed to compare the effects of rescue ventilation maneuvers on the quality of two-rescuer cardiopulmonary resuscitation (CPR). Methods: We implemented mouth to mouth (MMV), mouth to pocket mask (MPV) and bag-valve mask ventilation (BMV) maneuvers. Each team of two-nurses was randomized to perform three consecutive sessions of two-rescuer CPR by using three artificial ventilation maneuvers. Results: The subjects were 26 teams of nurses (female: 96.2%, male: 3.8%, age: 26.6 years). Failed ventilation was more frequent in BMV ($2.23{\pm}2.21$, p <.001) than MMV ($0.31{\pm}0.74$) and MPV ($0.38{\pm}0.64$). BMV had more compressions per minute ($93.7{\pm}5.7$) than MMV ($87.0{\pm}7.2$, p = .001) and shorter total compression pause time ($46.1{\pm}5.8sec$) and compression pause fraction ($23.3{\pm}2.2%$) than MMV ($54.8{\pm}10.3sec$, p = .001, $25.5{\pm}3.5%$, p = .001, respectively) and MPV ($53.1{\pm}7.1sec$, p =. 006 and $25.8{\pm}2.6%$, p = .006, respectively). Conclusion: In our simulation study, BMV reduced the compression pause time and increased the number of compressions per minute, thus indicating CPR provided to patients was effective. However, considering the high rate of ventilation failure, we recommend periodic training.

Three-Dimensional Self-Assembly of Gold Nanoparticles Using a Virus Scaffold

  • Kang, Aeyeon;Lee, Young-Mi;Kang, Hyo Jin;Chung, Sang Jeon;Yun, Wan Soo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.651-651
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    • 2013
  • Templated strategy is a very powerful tool for creating multi-dimensional self assembly of nanomaterials. Since viral protein cages have a uniform size with a well-defined structure, they can serve as an excellent template for the formation of a three-dimensional self-assembly of synthetic nanoparticles. In this study, we have examined the feasibility of the 3D self-assembly of gold nanoparticles of various sizes using a brome mosaic virus (BMV) capsid with cysteine groups expressed on its surface as a scaffold for the assembly. It was found that the three-dimensional clusters of gold nanoparticles with a designed structure were attainable by this approach, which was verified by transmission electron microscope (TEM) and dynamic light scattering (DLS) analysis.

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A Low-cost Fire Detection System using a Thermal Camera

  • Nam, Yun-Cheol;Nam, Yunyoung
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.3
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    • pp.1301-1314
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    • 2018
  • In this paper, we present a low-cost fire detection system using a thermal camera and a smartphone. The developed system collects thermal and RGB videos from the developed camera. To detect fire, candidate fire regions are extracted from videos obtained using a thermal camera. The block mean of variation of adjacent frames is measured to analyze the dynamic characteristics of the candidate fire regions. After analyzing the dynamic characteristics of regions of interest, a fire is determined by the candidate fire regions. In order to evaluate the performance of our system, we compared with a smoke detector, a heat detector, and a flame detector. In the experiments, our fire detection system showed the excellent performance in detecting fire with an overall accuracy rate of 97.8 %.

Neurofluid Dynamics and the Glymphatic System: A Neuroimaging Perspective

  • Toshiaki Taoka;Shinji Naganawa
    • Korean Journal of Radiology
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    • v.21 no.11
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    • pp.1199-1209
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    • 2020
  • The glymphatic system hypothesis is a concept describing the clearance of waste products from the brain. The term "glymphatic system" combines the glial and lymphatic systems and is typically described as follows. The perivascular space functions as a conduit that drains cerebrospinal fluid (CSF) into the brain parenchyma. CSF guided to the perivascular space around the arteries enters the interstitium of brain tissue via aquaporin-4 water channels to clear waste proteins into the perivascular space around the veins before being drained from the brain. In this review, we introduce the glymphatic system hypothesis and its association with fluid dynamics, sleep, and disease. We also discuss imaging methods to evaluate the glymphatic system.

Comparison of Ventilation Effects by Mask Type for Proper Health Care of Respiratory Emergency Patients (호흡응급환자의 적절한 헬스케어를 위한 마스크 유형별 환기효과 비교)

  • Kim, Tae-Hyun;Park, Si-Eun
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.7
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    • pp.477-485
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    • 2020
  • This study is a random allocation similar experimental study to compare and analyze the difference in BVM (Bag-Valve-Mask) ventilation volume according to the characteristics of the rescuer's hand and the type of mask using a standardized mannequin. To this end, the Basic Life Resuscitation Education Center of D University in gwangju. Recruiting 39 students who have completed the basic resuscitation course for emergency medical personnel and the Korean-style specialized cardiac rescue course, In addition to measuring the physical characteristics of the hand, the average amount of ventilation per minute using a bag-mask was measured and analyzed. As a result, the type of mask that was not most affected by the characteristics of the hand and provided adequate Minute Ventilation was the soft type (tube, silicone) mask. On the other hard (tube, silicone) masks were found to be unsuitable for general use as they were greatly affected by the characteristics of workers' hands. COVID-19 is currently increasing the risk of transmission to paramedics and patients. Considering this situation, the universal use of a semi-permanent hard-type mask, which is disadvantageous not only for preventing infection but also for proper ventilation, should be avoided. In addition to the ease of use, it should be actively utilized in the field by supplying a soft type mask that can provide stable ventilation even with 'predominance recognition' and proper ventilation.