• 제목/요약/키워드: Reproduction. Transmission

검색결과 109건 처리시간 0.028초

국내외 공기감염 분야 연구동향 (Review of Recent Studies on the Airborne Infection)

  • 권순박;김창수
    • 한국입자에어로졸학회지
    • /
    • 제6권2호
    • /
    • pp.81-90
    • /
    • 2010
  • Several studies have suggested the possibility of airborne transmission of infectious diseases such as tuberculosis, pandemic influenza. because the number of patients increases explosively, if infectious disease had a high basic reproduction number, pharmaceutical interventions such as vaccination, chemoprophylaxis in the early stage of epidemic. Thus, non-pharmaceutical interventions such as mask-wearing, installing air cleaners, school closure are important to control and prevent the infectious diseases. However, the current technology on the mask, air cleaning, ventilation, and etc., seems to be not originated from the understanding of infection via airborne transmission. It is important to estimate the aerodynamic behavior of saliva droplets by coughing or speaking in order to understand the phenomena of airborne infection. In addition, the prediction of transmission of infectious diseases through the air is critical to prevent or minimize the damage of infection. In this review, we reviewed the recent studies on the airborne infection by focusing on the aerodynamic characteristics of saliva droplets and modeling of airborne transmission.

주요국 저작권법의 도서관 예외 규정 비교 분석 (A Comparative Analysis of the Library Exceptions in Copyright Laws in Major Countries)

  • 정경희
    • 정보관리학회지
    • /
    • 제34권1호
    • /
    • pp.263-289
    • /
    • 2017
  • 본 연구는 저작권법의 도서관 예외규정에 대한 이해를 높이고 국내 규정의 개선방향을 모색하기 위한 것이다. 이를 위하여 한국, 일본, 영국, 호주, 미국의 저작권법에서 도서관 예외규정을 비교분석하였다. 그 결과 이용자를 위한 복제물 제공, 보존을 위한 복제, 상호대차를 위한 복제, 도서관자료의 디지털화를 위한 복제 등이 대표적인 예외규정이었으나 그 세부 조건은 국가마다 상당한 차이가 있었다. 본 연구는 우리나라 저작권법의 도서관 예외규정에서 미공표저작물 및 구하기 힘든 저작물과 정기간행물에 대한 이용자용 복제의 분량 재조정, 제한된 조건하에서 이용자에게 디지털 복제물을 전송, 자체 보존용 복제가 가능한 조건 마련, 상호대차 근거규정 마련, 디지털화 대상범위 제한과 이용범위 확대 등을 제안하였다.

Interpretation of the Basic and Effective Reproduction Number

  • Lim, Jun-Sik;Cho, Sung-il;Ryu, Sukhyun;Pak, Son-Il
    • Journal of Preventive Medicine and Public Health
    • /
    • 제53권6호
    • /
    • pp.405-408
    • /
    • 2020
  • In epidemiology, the basic reproduction number (R0) is a term that describes the expected number of infections generated by 1 case in a susceptible population. At the beginning of the coronavirus disease 2019 (COVID-19) pandemic, R0 was frequently referenced by the public health community and the wider public. However, this metric is often misused or misinterpreted. Moreover, the complexity of the process of estimating R0 has caused difficulties for a substantial number of researchers. In this article, in order to increase the accessibility of this concept, we address several misconceptions related to the threshold characteristics of R0 and the effective reproduction number (Rt). Moreover, the appropriate interpretation of the metrics is discussed. R0 should be considered as a population-averaged value that pools the contact structure according to a stochastic transmission process. Furthermore, it is necessary to understand the unavoidable time lag for Rt due to the incubation period of the disease.

암호화 모듈을 적용한 콘텐츠 전송 시스템 (Contents Transmission System applied by Encryption Module)

  • 박순홍;최승권;신승수;조용환
    • 한국콘텐츠학회:학술대회논문집
    • /
    • 한국콘텐츠학회 2003년도 춘계종합학술대회논문집
    • /
    • pp.165-170
    • /
    • 2003
  • 본 논문에서는 암호화 모듈을 적용한 콘텐츠 전송 시스템을 제안한다. 사용자측의 전용 브라우저를 통해 RSA 암호화 알고리즘과 XOR 연산 기법으로 암호화된 콘텐츠를 제공함으로써 콘텐츠 불법 유통과 불법 복제를 방지하고 기존의 콘텐츠 전송 시스템들이 전송 도중의 공격에 취약한 점을 보완한다. 또한 재생 완료 즉시 전용 브라우저로 암호키를 갱신함으로써 콘텐츠와 전용 브라우저를 1:1 관계로 묶어 저작권을 보호한다.

  • PDF

형질전환 생쥐에서 Bovine $\beta$-Casein/Bovine Growth Hormone 재조합 유전자의 유전적 안정성에 관한 연구 (Stable Inheritance of Bovine $\beta$-Casein/Bovine Growth Hormone Fusion Gene in Transgenic Mice)

  • 최영희;오건봉;강용국;방남수;서길웅;이경광;이철상
    • 한국가축번식학회지
    • /
    • 제22권3호
    • /
    • pp.237-244
    • /
    • 1998
  • To investigate the fidelity of transgene transmission and expression, we produced transgenic mice carrying bovine $\beta$-casein/bovine grwoth hormone(bGH) fusion gene and examined transmission efficiency and expression level of the transgene in the founders and their progeny. The transgene was composed of 1.8 kb bovine $\beta$-casein promoter and 2.1 kb bGH gene. Ten transgenic mice were produced. Milk and mammary gland were collected from eight transgenic lines at 10-day lactation and a, pp.ied to Western and Northern blot analyses. The bGH expression was detected in four of them. The concentrations of bGH in milk were highly variable from 4$\mu\textrm{g}$/ml to 600$\mu\textrm{g}$/ml depending on the lines. The bGH mRNA level in mammary gland was closely correlated with the bGH concentration in milk in each transgenic line. These results indicated that bGH transgene expression was a, pp.opriately regulated in the mammary gland and secreted into milk in transgenic mice. By using two transgenic lines(#2, #7) secreting a considerable amoung of bGH into their milk, the inferitance and maintenance of transgenic phenotype were assessed in successive four generations. The mean transmission frequencies of transgene in lines #2 and #7 were 34% and 40%, respectively. The bGH concentration in milk were 80, 240, 120, 60$\mu\textrm{g}$/ml in each G0(generation 0), G2, G3, G4 generation of line #2 and 600, 1600, 860, 900$\mu\textrm{g}$/ml in each G1. G2, G3, G4 generation of line #7. These results demonstrated that bovine $\beta$-casein/bGH gene was stably transmitted from generation to generation in a Menelian fashion in trasgenic mice and consistenly expressed in their milk throughout the generations, although there was a little variation in the transmission frequency and expression level of the transgene between generations.

  • PDF

발달 단계에 따른 한국산 메기(Silurus asotus) 난모세포의 미세구조적 변화 (Ultrastructural Changes of Oocyte in Korean Catfish, Silurus asotus)

  • 윤종만;김계웅;신호철;장계남;류동석;박홍양
    • 한국가축번식학회지
    • /
    • 제19권2호
    • /
    • pp.105-117
    • /
    • 1995
  • This study was carried out to investigate the histomorphological changes and the electrophoretic patterns of egg components, obtained from 100 of 1-year-old female catfish(Silurus asotus). Especially, the light microscopic and ultrastructural changes of ooplasm and follicular membranes of oocytes, were observed by light and transmission electron microscope. All data were collected from October in 1992 to May in 1993. The size of the nucleoli and number of the yolk granules increased as the oocyte grew. Yolk granules were deposited in the oocyte as fluid. Due to the presence of large early and late maturing oocytes, their ovaries were large, transparent, granular, and greenish in color. As the percentages of fish in LMO and RO stage increased from March to April, mean of GSI values(19.95%) increased. Follicle cells such as granulosa cell and thecal cell change a squamous into cuboid shape in LPO and EMO stage. Processes, microvilli, from the granulosa cells and from the oocyte grow and make contact with each other in the pore canals of the zona radiata during vitellogenesis, but are withdrawn as the zona radiate becomes more compact and devoid of pore canals during oocyte maturation. The electrophoretic pattern of major band in mature stage was much thicker(21k, 24k, 32k, 45k, 67∼110k, 170k dalton) than that in previtellogenic phase.

  • PDF

저작권법상 도서관관련 권리제한의 개정안 연구 (A Study on the Revision of Copyright Limitations for Libraries in Copyright Law of Korea)

  • 윤희윤
    • 정보관리연구
    • /
    • 제42권2호
    • /
    • pp.1-21
    • /
    • 2011
  • 저작권법은 저작권 소유자의 권리와 이용자의 권리 간에 균형을 유지함으로써 지식정보에 대한 접근을 촉진하는 최선의 법적 도구이다. 이러한 측면에서 도서관을 위한 저작권의 제한 및 예외는 학습과 연구를 지원하고 정보의 흐름을 촉진하며, 대중에게 공정한 정보접근을 제공하고 지적 문화유산을 보존하는 데 중요하다. 이에 본 연구는 국내 저작권법의 도서관관련 권리제한조항을 축조분석하여 도서관 보관자료의 보존 및 제공용 복제, 도서관에서 인터넷 정보의 출력과 송신, 재생수단의 입수가 곤란한 자료 및 정부간행물의 보존용 복제와 제공, 장애인을 위한 도서관의 복제와 공중송신에 대한 개선방안을 제시하고 공정이용을 위한 일반규정의 도입방안을 제안하였다.

Basic reproduction number of African swine fever in wild boars (Sus scrofa) and its spatiotemporal heterogeneity in South Korea

  • Lim, Jun-Sik;Kim, Eutteum;Ryu, Pan-Dong;Pak, Son-Il
    • Journal of Veterinary Science
    • /
    • 제22권5호
    • /
    • pp.71.1-71.12
    • /
    • 2021
  • Background: African swine fever (ASF) is a hemorrhagic fever occurring in wild boars (Sus scrofa) and domestic pigs. The epidemic situation of ASF in South Korean wild boars has increased the risk of ASF in domestic pig farms. Although basic reproduction number (R0) can be applied for control policies, it is challenging to estimate the R0 for ASF in wild boars due to surveillance bias, lack of wild boar population data, and the effect of ASF-positive wild boar carcass on disease dynamics. Objectives: This study was undertaken to estimate the R0 of ASF in wild boars in South Korea, and subsequently analyze the spatiotemporal heterogeneity. Methods: We detected the local transmission clusters using the spatiotemporal clustering algorithm, which was modified to incorporate the effect of ASF-positive wild boar carcass. With the assumption of exponential growth, R0 was estimated for each cluster. The temporal change of the estimates and its association with the habitat suitability of wild boar were analyzed. Results: Totally, 22 local transmission clusters were detected, showing seasonal patterns occurring in winter and spring. Mean value of R0 of each cluster was 1.54. The estimates showed a temporal increasing trend and positive association with habitat suitability of wild boar. Conclusions: The disease dynamics among wild boars seems to have worsened over time. Thus, in areas with a high elevation and suitable for wild boars, practical methods need to be contrived to ratify the control policies for wild boars.

디지털 도서관의 저작물 전송 활성화 방안 - 저작권과 관련한 제도적.기술적 측면을 중심으로 - (A Study on Transmisson of Copyrighted Works in Digital Library - The Systematic and Technological Solutions Relating to Copyright -)

  • 홍재현
    • 한국비블리아학회지
    • /
    • 제11권1호
    • /
    • pp.67-92
    • /
    • 2000
  • 본 연구의 목적은 저작권과 관련하여 디지털 도서관에서의 저작물의 전송 서비스를 활성화시키기 위한 방안을 제도적$.$기술적 측면에서 제시함으로써 디지털 도서관의 구축과 원문정보 제공 서비스를 촉진시키는데 있다. 이를 위하여 디지털 도서관의 정의, 특징 등을 고찰하였고 우리나라와 일본, 미국의 디지털 도서관의 정보서비스 현황을 검토하였다. 그리고 1999년 12월에 개정된 저작전법의 온라인 전송과 도서관 관련 규정을 살펴보았다. 끝으로 복사권 집중관리기구의 설립과 권리보호를 위한 기술조치의 도입 방안을 제시하였다.

  • PDF

성장호르몬수용체 유전자를 지닌 형질전환생쥐의 세대전달율 및 치사율 (Transmission and Death Rates in Transgenic Mice Containing Growth Hormone Receptor Gene)

  • Kim, H.J.;Jin, D.I.
    • 한국가축번식학회지
    • /
    • 제25권1호
    • /
    • pp.85-90
    • /
    • 2001
  • 본 연구는 growth hormone receptor(GHR) gene의 동물생리에 미치는 영향을 연구하기 위해 metallothionein promoter와 GHR gene을 이용하여 생쥐의 1-cell 수정란에 DNA 미세주입법에 의해 형질전환생쥐를 생산하였다. 세마리의 형질전환생쥐가 생산되었는데 DNA 분석결과 4~8 copy의 GHR 유전자를 지닌 것으로 확인되었다 이들 세 마리의 GHR 형질전환생쥐를 정상 형질전환생쥐와 교미시켜 F$_1$과 F$_2$ 새끼를 생산하였는데 이들의 전달율은 F$_1$에서 20~50%였고 F$_2$에서는 약 50%를 나타내어 모자익형태로 유전자가 정착되었음을 확인할 수 있었다. 3주령까지의 사망률은 Fl과 F2 새끼에서 약 10~30%를 나타내어 GHR유전자의 발현이형질전환생쥐의 초기 사망에 영향을 미치는 것으로 나타났다.

  • PDF