• 제목/요약/키워드: Accumulation counter

검색결과 29건 처리시간 0.022초

동물체모 및 장기 중 카드뮴의 방사화 분석 (Neutron Activation Analysis of Cadmium Deposition in Hair and Animal Tissues)

  • 유용운;이기호
    • Journal of Radiation Protection and Research
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    • 제15권2호
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    • pp.17-25
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    • 1990
  • 백서의 장기 내 카드뮴의 축적분포를 중성자 조사에 의한 방사분석법으로 조사하였다. $CdCl_2$를 1주일에 10mg/kg씩 급식되도록 매일 물병으로 투여하였으며 1주, 2주, 3주, 1개월, 2개월 및 3개월 기간동안 장기 복용케한 후 주요장기 및 체모를 시료로 하여 방사화 분석을 수행하여 아래와 같은 결론을 얻었다. 1) $^{115m}Cd$을 방사추적자로 사용하여 24시간 경과 후 체내 카드뮴의 분포를 조사한 결과 혈액에 0.03% 신장에 2.99% 간장에 3.50%를 나타내었다. 2) Cd은 혈액을 통해 신속히 순환되어 신장을 통하여 배설되나 간장과 체모에도 축적되는 결과를 나타냈다. 3) $CdCl_2$를 급식케 한 실험군의 주요 장기별 Cd함량을 측정 비교한 결과를 이용하여 간장 내 Cd의 축적을 체모 내 Cd함량으로부터 진단하는 지표로 사용이 가능케 되었다.

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양자내성암호 NTRU에 대한 전력 부채널 공격 및 대응방안 (Power-Based Side Channel Attack and Countermeasure on the Post-Quantum Cryptography NTRU)

  • 장재원;하재철
    • 정보보호학회논문지
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    • 제32권6호
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    • pp.1059-1068
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    • 2022
  • 양자 컴퓨터의 계산 능력을 고려하여 설계된 양자 내성 암호 NTRU는 수학적으로 안전한 암호 조건을 만족하지만 하드웨어 구현 과정에서는 전력 분석 공격과 같은 부채널 공격 특성을 고려해야 한다. 본 논문에서는 NTRU의 복호화 과정 중 발생하는 전력 신호를 분석할 경우 개인 키가 노출될 가능성이 있음을 검증한다. 개인 키를 복구하는 데에는 단순 전력 분석 공격(Simple Power Analysis, SPA), 상관 전력 분석 공격(Correlation Power Analysis, CPA)과 차분 딥러닝 분석 공격(Differential Deep Learning Analysis, DDLA)을 모두 적용할 수 있었다. 이러한 전력 부채널 공격에 대응하기 위한 기본적인 대응책으로 셔플링 기법이 있으나 보다 효과적인 방법을 제안한다. 제안 방식은 인덱스별로 곱셈(multiplication)후 누산(accumulation)을 하는 것이 아니라 계수별로 누산 후 덧셈만 하도록 함으로써 곱셈 연산에 대한 전력 정보가 누출되지 않도록 하여 CPA 및 DDLA 공격을 방어할 수 있다.

Poly-${\gamma}$ Benzyl $_D$-Glutamate 유기박막의 전자이동특성에 관한 연구 (A Study on the Electronic Properties of Poly-$\gamma$ Benzyl $_D$-Glutamate Organic Thin Films)

  • 송진원;이경섭;이봉주;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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    • pp.86-89
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    • 2002
  • We give pressure stimulation into organic thin films and then manufacture a device under the accumulation condition that the state surface pressure is 10[mN/m]. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/Poly-${\gamma}$ Benzyl $_D$-Glutamate/Al and Au/Poly-${\gamma}$ Benzyl $_D$-Glutamate/Au; the number of accumulated layers is 1, 3, 5 and 7. Also, we then examined of the MIM device by means of I-V. The I-V characteristic of the device is measured from 0 to +2[V]. We determined electrochemical measurement by using cyclic voltammetry with a three-electrode system. LB film accumulated by monolayer on an ITO. In the cyclicvoltammetry, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode measured in $LiBF_4$ solution, stable up to 0.9V vs. Ag/AgCl.

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인공위성의 오염 측정, 분석 및 관리 (Contamination measurement, Analysis & Control for Satellite)

  • 이상훈;홍석종;조혁진;서희준;문귀원
    • 항공우주기술
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    • 제9권2호
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    • pp.116-122
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    • 2010
  • 우주환경에서 임무를 수행하는 인공위성의 경우, 조립, 시험, 운용시점까지 위성 표면에 흡착되는 오염물질을 최소화하기 위하여 전 기간 동안 세심한 주의를 기울여야 한다. 위성표면에 흡착된 미세한 오염물질은, 고진공 및 고온, 극저온이 반복되는 가혹한 우주환경 속에서 위성의 성능저하 및 효율의 손실을 가져올 수 있다. 예를 들어 위성 표면에 떨어진 입자오염은 별 추적장치의 오류를 발생시킴에 따른 위성 자세제어의 실패를 가져올 수도 있고, 표면에 흡착된 분자오염은 렌즈, 미러, 윈도우 등의 광학기기 및 주요 민감 표면에 작용하여 광학적 특성과 열제어 성능의 저하를 가져올 수 있다. 위성의 조립 및 시험을 관장하는 한국항공우주연구원에서는 위성의 오염물질에 대한 노출을 최소화하기 위해, 오염측정이 이루어지는 청정실을 운용하고 있는데, 본 논문에서는 청정실 및 진공챔버 내의 부유입자측정, 표면입자오염측정, 표면분자오염측정법을 소개하고 오염측정 결과에 대한 분석을 수행하였다.

Metal/Organic Films/Metal에서 계면특성에 관한 연구 (A Study on the Interface Properties of Metal/Organic Films/Metal)

  • 송진원;조수영;최영일;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.723-726
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    • 2002
  • We give pressure stimulation into organic thin films and then manufacture a device under the accumulation condition that the state surface pressure is 10[mN/m]. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/Poly-$\gamma$ Benzyl $_D$-Glutamate/Al; the number of accumulated layers is 1, 3, 5 and 7. Also, we then examined of the MIM device by means of I-V. The I-V characteristic of the device is measured from 0 to +2[V]. We determined electrochemical measurement by using cyclic voltammetry with a three-electrode system. LB film accumulated by monolayer on an ITO. In the cyclicvoltammetry, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode measured in $LiBF_4$ solution, stable up to 0.9V vs. Ag/AgCl.

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Pretargeting : A concept refraining traditional flaws in tumor targeting

  • Bhise, Abhinav;Yoo, Jeongsoo
    • 대한방사성의약품학회지
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    • 제6권1호
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    • pp.53-58
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    • 2020
  • Pretargeting is a two-component strategy often used for tumor targeting to enhance the tumor-to-background ratio in cancer diagnosis as well as therapy. In the multistep strategy, the highly specific unlabeled monoclonal antibodies (mAbs) with the reactive site is allowed to get localized at tumor site first, and then small and fastclearing radiolabeled chelator with counter reactive site is administered which covalently attaches to mAbs via inverse electron demand Diels-Alder reaction (IEDDA). The catalyst-free IEDDA cycloaddition reaction between 1,2,4,5-tetrazines and strained alkene dienophiles aid with properties like selective bioconjugation, swift and high yielding bioorthogonal reactions are emergent in the development of radiopharmaceutical. Due to its fast pharmacokinetics, the in vivo formed radioimmunoconjugates can be imaged at earlier time points by short-lived radionuclides like 18F and 68Ga; it can also reduce radiation damage to the normal cells. Ultimately, this review elucidates the updated status of pretargeting based on antibodies and IEDDA for tumor diagnosis (PET and SPECT) and therapy.

Enhancement of Erythropoietin Production from Chinese Hamster Ovary(CHO) Cells by Introduction of the Urea Cycle Enzymes, Carbamoyl Phosphate Synthetase I and Ornithine Transcarbamylase

  • Kim, Na-Young;Lee, Yun-Jeong;Kim, Hyung-Jin;Choi, Jung-Ho;Kim, Jung-Kwon;Chang, Kern-Hee;Kim, Jung-Hoe;Kim, Hong-Jin
    • Journal of Microbiology and Biotechnology
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    • 제14권4호
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    • pp.844-851
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    • 2004
  • Efficient mammalian erythropoietin (EPO)-expression systems are required for therapeutic applications. The accumulation of ammonia is a major problem in the production of recombinant proteins in cultured animal cells. To counter this problem we introduced the first two genes of the urea cycle, carbamoyl phosphate synthetase (CPSI) and ornithine transcarbamylase (OTC), into IBE Chinese Hamster Ovary (CHO) cells by stable transfection. The resulting cell line, CO5, had a higher growth rate and accumulated less ammonia per cell than the parental cell line, IBE. In addition, it produced 2 times more EPO than the parent, and the purified EPO contained a higher proportion of acidic isoforms with approximately 15% more sialic acid.

LB박막의 전자이동 특성에 관한 연구 (A Study on the Electronic Properties of LB Thin Films)

  • 송진원;최영일;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 제4회 영호남학술대회 논문집
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    • pp.101-104
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    • 2002
  • Abstract We give pressure stimulation into organic thin films and then manufacture a device under the accumulation condition that the state surface pressure is 10[mN/m]. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/Poly-${\gamma}$ Benzyl $_D$-Glutamate/Al; the number of accumulated layers is 1, 3, 5 and 7. Also, we then examined of the MIM device by means of I-V. The I-V characteristic of the device is measured from 0 to +2[V]. We determined electrochemical measurement by using cyclic voltammetry with a three-electrode system. LB film accumulated by monolayer on an ITO. In the cyclicvoltammetry, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode measured in $LiBF_4$ solution, stable up to 0.9V vs. Ag/AgCl.

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The Relationship between Prohibitin 1 Expression, Hepatotoxicity Induced by Acetaminophen, and Hepatoprotection by S-Adenosylmethionine in AML12 Cells

  • Eunhye Cho;Soohan Jung;Jina Kim;Kwang Suk Ko
    • Journal of Microbiology and Biotechnology
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    • 제32권11호
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    • pp.1447-1453
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    • 2022
  • Prohibitin 1 (Phb1) is a pleiotropic protein, located mainly in the mitochondrial inner membrane and involved in the regulation of cell proliferation and the stabilization of mitochondrial protein. Acetaminophen (APAP) is one of the most commonly used over-the-counter analgesics worldwide. However, at high dose, the accumulation of N-acetyl-p-benzoquinone imine (NAPQI) can lead to APAP-induced hepatotoxicity. In this study, we sought to understand the regulation of mRNA expression in relation to APAP and GSH metabolism by Phb1 in normal mouse AML12 hepatocytes. We used two different Phb1 silencing levels: high-efficiency (HE, >90%) and low-efficiency (LE, 50-60%). In addition, the siRNA-transfected cells were further pretreated with 0.5 mM of Sadenosylmethionine (SAMe) for 24 h before treatment with APAP at different doses (1-2 mM) for 24 h. The expression of APAP metabolism-related and antioxidant genes such as Cyp2e1 and Ugt1a1 were increased during SAMe pretreatment. Moreover, SAMe increased intracellular GSH concentration and it was maintained after APAP treatment. To sum up, Phb1 silencing and APAP treatment impaired the metabolism of APAP in hepatocytes, and SAMe exerted a protective effect against hepatotoxicity by upregulating antioxidant genes.