• 제목/요약/키워드: Ab

검색결과 3,075건 처리시간 0.028초

W UMa형 접촉쌍성 AB And의 주기변화 (PERIOD CHANGE OF W UMa TYPE CONTACT BINARY AB And)

  • 진호;한원용;김천휘;이재우;이우백
    • Journal of Astronomy and Space Sciences
    • /
    • 제14권2호
    • /
    • pp.242-250
    • /
    • 1997
  • W UMa형 접촉쌍성 AB And의 BVR CCD 측광 관측을 1994년 9월부터 1996년 10까지 4일간 수행하여 4개의 새로운 극심 시간을 결정하였다. 이 극심 시각과 이제까지 발표된 모든 극심 시각을 분석하여 AB And의 주기변화의 양상을 연구하였다. AB And의 주기변화를 sine 함수와 같이 규칙적으로 변한다고 가정하여, 관측된 극심 시간을 가장 잘 맞추는 광도 요소를 구하였다. 이 광도요소의 sine 항으로부터 계산된 AB And의 공전주기 변화는 약 0.059일의 진폭으로 약 92년 주기로 규칙적으로 변화하고 있다. 그러나 가장 최근에 관측된 이 연구의 극심 시각들은 이 광도요소에서 예측한 극심 시각들보다 다소 크게 나타나고 있다. 따라서, 우리는 AB An의 공전주기가 sine 함수 외에도 포물선 형태로 변한다고 가정하고 관측된 극심 시각을 가장 잘 맞추는 광도요소를 구하였다. 이 광도요소의 이차항으로 계산된 AB And의 공전주기는 100년에 약 0.73초만큼 영 년 증가하는 동시에, sine 항으로부터 약 62.9년 주기와 0.024일의 진폭으로 규칙적으로 변화한다는 것을 알 수 있었다. 따라서 향후 10년 이내에는 AB And의 공전주기는 sine 항만을 고려하면 주기 감소를 해야하고, 이차항까지 고려하면, 주기 증가가 예측되므로, AB And의 주기변화에 대한 명확한 해답을 위해서 지속적인 관측이 요구된다.

  • PDF

B형간염바이러스 및 C형간염바이러스의 표식자 양성율과 원발성 간세포 암의 연관성에 대한 환자-대조군 연구 (A Case-Control Study on Association Between Hepatocellular Carcinoma and Infection of Hepatitis B and Hepatitis C Virus)

  • 안형식;김민호;김영식;김정순
    • Journal of Preventive Medicine and Public Health
    • /
    • 제30권1호
    • /
    • pp.1-15
    • /
    • 1997
  • To investigate the association between hepatocellular carcinema(HCC) and infection of hepatitis B virus(HBV) and hepatitis C virus(HCV) in an HBV endemic area, a case-control study of 254 patients with HCC and of 1,270 age and sex matched health control subjects was done. Among the 254 HCC patients 166(65.4%) were positive for hepatitis B surface antigen(HBsAg), 49(19.3%) were positive for HCV antibody (anti-HCV Ab). The crude odd ratio of patients with HBsAg was 36.1(95% CI :22.4-58.2) and with anti-HCV Ab was 9.0(95% CI :5.5-14.6). In an analysis, which HBsAg(-), HBcAb(-), anti-HCV Ab(-) group was chosen as referent group, odd ratio of HBsAg(+) group was 14.4(95% CI: 7.2-28.9) and of anti- HCV Ab(+) was 10.7(95% CI: 2.9-40.0). odd ratio of anti-HCV Ab(+), HBsAg(+) group and anti-HCV Ab(+), HBsAg(-), HbcAb(+) group for HCC were elevated to 27.3(95% CI : 9.0-82.9), 15.9(95% CI:7.1-35.8) respectly, The odd ratio of anti-HCV Ab(-), HBsAg(-), HBcAb(+) group was 2.4(95% CI : 1.1-5.0). These result suggested that HBV and HCV were associated with HCC. In HBV endemic area patients with HBcAb alone should be considered risk group for HCC.

  • PDF

분할된 $AB^2$ 시스톨릭 모듈러 곱셈기 설계 (Design of Partitioned $AB^2$ Systolic Modular Multiplier)

  • 이진호;김현성
    • 한국통신학회논문지
    • /
    • 제31권1C호
    • /
    • pp.87-92
    • /
    • 2006
  • [ $AB^2$ ]연산은 공개키 암호화 시스템을 위한 효율적인 기본 연산으로 알려져 있고 이를 위한 다양한 하드웨어가 설계되었다. 그러나 이들 구조들은 암호학적 응용에 사용되기에는 구조복잡도가 크다는 문제점이 있었다. 본 논문에서는 GF($2^m$)상에서 공간 효율적인 분할된 $AB^2$ 시스톨릭 모듈러 곱셈기를 설계한다. MSB $AB^2$ 모듈러 곱셈 알고리즘으로부터 데이터 의존 그래프를 유도하고 유도된 의존 그래프를 1/3로 분할함으로서 공간 효율적인 분할된 $AB^2$ 시스톨릭 곱셈기를 설계한다. 본 논문에서 제안한 곱셈기는 기존의 곱셈기와 비교하여 2/3정도의 구조 복잡도를 줄일 수 있다. 본 논문에서 제안한 구조는 크기에 제한을 갖는 스마트 카드 등에서 사용될 공개키 암호의 핵심이 되는 지수기의 구현을 위한 효율적인 기본구조로 사용될 수 있을 것이다.

In Vitro α-Amylase, α-Glucosidase, Pancreatic Lipase, Xanthine Oxidase Inhibiting Activity of Agaricus bisporus Extracts

  • Jung Han Kim;Myoung Jun Jang;Youn Jin Park
    • Mycobiology
    • /
    • 제51권1호
    • /
    • pp.60-66
    • /
    • 2023
  • In this study, the α-amylase inhibitory activity, α-glucosidase inhibitory activity, pancreatic lipase inhibitory activity, and Xanthine Oxidase inhibitory activity of the fruiting body extracts of 5 varieties of Agaricus bisporus (AB) were confirmed. First, the α-amylase inhibitory activity of AB12, AB13, AB18, AB34, and AB40 methanol extracts was lower than that of acarbose, a positive control, in all concentration ranges. The α-glucosidase inhibitory activity of the AB40, AB13, and AB12 methanol extracts at the extract concentration of 1.0 mg/mL was 80.5%, 81.3%, and 78.5%, respectively, similar to that of acarbose, a positive control. The pancreatic lipase inhibitory activity of the methanol extract of Agaricus bisporus fruiting body was significantly lower than that of the positive control orlistat in the concentration range of 50~1.000 (mg/mL). The Xanthine Oxidase inhibitory activity was 0.5~8.0 mg/mL of each extract, which was significantly lower than that of the positive control allopurinol in the same concentration range. However, the Xanthine Oxidase inhibitory activity of AB13 and AB40 at 8.0 mg/mL was about 70%, which was higher than that of other mushrooms. In conclusion, five kinds of Agaricus bisporus fruiting bodies seem to have inhibitory effects on enzymes such as α-amylase, α-glucosidase, pancreatic lipase, and Xanthine Oxidase that degrade starch and protein. In particular, it has an inhibitory effect and a reduction effect on xanthine oxidase that causes gout, so it is expected that it can be developed and used as a food or health supplement with health functional properties through future research.

Genetically modified carrot cells acquiring desiccation tolerance

  • Kamada, Hiroshi;Shiota, Hajime
    • 한국식물학회:학술대회논문집
    • /
    • 한국식물학회 1999년도 제13회 식물생명공학심포지움 New Approaches to Understand Gene Function in Plants and Application to Plant Biotechnology
    • /
    • pp.75-78
    • /
    • 1999
  • To obtain direct evidence for thed involvement of C-AB13, a carrot (Daucus carota L.) homolog of VPI/Ab13, seed-specific transcription factor, in the acquisition of desiccation tolerance carrot non-embryogenic cells (NC) in which the C-AB13 gene was expressed ectopically was prepared. Non-transgenic NC, in which expression of C-AB13 was not detected, did not exhibit desiccation tolerance even after treatment with abscisic acid (ABA). In transgenic NC that expressed C-AB13, embryo-specific ABA-inducible genes (ECP genes) were expressed upon ABA-treatment. Furthermore, the transgenic NC became desiccation-tolerant upon ABA-treatment, but not tolerate desiccation without ABA-treatment. These results provide direct evidence for the involvement of C-AB13 in the ABA-induced acquisition of desiccation tolerance.

  • PDF

염증성 피부질환 개선 기능 소재로서 둥근전복(Haliotis discus) 유래 항균펩타이드 Ab4-7의 항염증 효과 (Anti-inflammatory Effects of Haliotis discus-derived Antibacterial Peptide (AMP) Ab4-7 as a Functional material for Improving Inflammatory Skin Diseases)

  • 최수철;서정길;황준호;이기영;이인아
    • 대한화장품학회지
    • /
    • 제46권2호
    • /
    • pp.147-157
    • /
    • 2020
  • 서해안에 서식하는 해양생물인 전복은 항산화 및 항염증 효과가 있으며, 항생제 개발 및 화장품 원료 등 다양한 산업에 활용될 수 있는 잠재력을 가진 자원이다. 본 연구에서 우리는 서해안의 다양한 해양 생물 중에서 전복을 선택하였으며, 전복에서 분리한 항균펩타이드(AMP)를 이용하여 항균펩타이드 유도체인 Ab4-7를 규명하고 생리활성을 연구하였다. Ab4-7의 항염증 효능을 확인하기 위해 염증이 유도된 RAW 264.7에 Ab4-7을 처리한 결과, 염증성 사이토카인, TLR4, TNF-α, IL-1β, COX-2, iNOS 등을 억제하고 항산화와 관련된 유전인자인 HO-1의 mRNA 발현을 증가시켰다. Ab4-7의 강력한 항산화 및 항염증 효과를 바탕으로, 염증이 유도된 RAW 264.7 세포에서 Ab4-7이 extrocellular matrix metalloproteinase (ECM) 분해에 관여하여 다양한 염증성 피부질환을 유도하는 유전자인 matrix metalloproteinase (MMPs)를 조절하는 효과를 RT-PCR을 통해 확인하였다. Ab4-7은 강력한 항염증 및 항산화 효과를 가지고 있으며, 항염증 및 항산화 효과를 통한 MMPs 관련 유전인자 조절을 통해 다양한 염증성 피부질환 치료제의 기능성 재료로 활용될 수 있다고 사료된다.

Clinical implications of anti-thyroglobulin antibody measurement before surgery in thyroid cancer

  • Jo, Kwanhoon;Lim, Dong-Jun
    • The Korean journal of internal medicine
    • /
    • 제33권6호
    • /
    • pp.1050-1057
    • /
    • 2018
  • Thyroglobulin antibody (TgAb) is a class G immunoglobulin and a conventional marker for thyroid autoimmunity. From a clinical perspective, TgAb is less useful than thyroid peroxidase antibodies for predicting thyroid dysfunction. However, TgAb is found more frequently in differentiated thyroid cancer (DTC) and can interfere with thyroglobulin (Tg) measurements, which are used to monitor the recurrence or persistence of DTC. Recent studies suggested a small but consistent role for preoperative TgAb in predicting DTC in thyroid nodules, and in reflecting adverse tumor characteristics or prognosis, including lymph node metastasis, but this is still controversial. Postoperative TgAb can serve as a biomarker for remnant thyroid tissue, so follow-up measures of TgAb are useful for predicting cancer recurrence in DTC patients. Since high serum TgAb levels may also affect the fine needle aspiration washout Tg levels from suspicious lymph nodes of DTC patients, it is important to use caution when interpreting the washout Tg levels in patients who are positive for TgAb.

$GF(2^m)$상에서 나눗셈/역원 연산을 위한 $AB^2$ 시스톨릭 어레이 설계 및 분석 (Design and Analysis of a $AB^2$ Systolic Arrays for Division/Inversion in$GF(2^m)$)

  • 김남연;고대곤;유기영
    • 한국정보과학회논문지:시스템및이론
    • /
    • 제30권1호
    • /
    • pp.50-58
    • /
    • 2003
  • $GF(2^m)$상의 공개키 암호 시스템에서 $AB^2$ 연산은 효율적이고 기본적인 연산으로 잘 알려져 있다. 나눗셈/역원은 기본이 되는 연산으로, 내부적으로 $AB^2$ 연산을 반복적으로 수행함으로써 계산이 된다. 본 논문에서는 $GF(2^m)$상에서$AB^2$ 연산을 수행하는데 필요한 새로운 알고리즘과 그에 따른 병렬 입/출력 및 시리얼 입/출력 구조를 제안한다. 제안된 알고리즘은 최상위 비트 우선 구조를 기반으로 하고, 구조는 기존의 구조에 비해 낮은 하드웨어 복잡도와 적은 지연을 가진다 이는 역원과 나눗셈 연산을 위한 기본 구조로 사용될 수 있으며 암호 프로세서 칩 디자인의 기본 구조로 이용될 수 있고, 또한 단순성, 규칙성과 병렬성으로 인해 VLSI 구현에 적합하다.

Effect of a Gluten Free Diet on Hepatitis B Surface Antibody Concentration in Previously Immunized Pediatric Celiac Patients

  • Zifman, Eyal;Zevit, Noam;Heshin-Bekenstein, Merav;Turner, Dan;Shamir, Raanan;Silbermintz, Ari
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • 제23권2호
    • /
    • pp.132-136
    • /
    • 2020
  • Purpose: To evaluate the effect of gluten-free diet (GFD) on hepatitis B surface antibody (HBsAb) concentrations among previously immunized pediatric celiac disease (CD) subjects. Methods: We retrospectively evaluated pediatric CD subjects in serological remission who were previously immunized for hepatitis B virus as infants. The temporal relationship between HBsAb concentration, the amount of time on a GFD, and age were evaluated. Results: Overall, 373 CD subjects were analyzed: 156 with HBsAb sampled prior to GFD initiation and 217 after initiation of a GFD and in serological remission. Median age at HBsAb concentration measurement for those before and after GFD initiation was 5.3 years (interquartile range [IQR], 3.1-9.2 years) and 7.6 years (IQR, 5.4-10.9 years), respectively (p<0.001). There was no sex difference between the groups. The median time of HBsAb measurement was 2 months (IQR, 0-5.7 months) before and 12.8 months (IQR, 5.3-30.3 months) after initiation of GFD. The HBsAb concentration was low in 79 (50.6%) and 121 (55.7%) subjects before and after GFD initiation, respectively (p=0.350). Age was inversely associated with low HBsAb concentrations. Neither being on a GFD nor sex was associated with low HBsAb concentrations. Conclusion: Adherence to a GFD does not affect HBsAb concentration in children with CD. Age is inversely associated with HBsAb concentration.

활 전복 수입에 의한 전복허피스바이러스감염증 (abalone herpes-like virus) 유입 위험평가 (A Stochastic Model to Quantify the Risk of Introduction of Abalone Herpes-like Virus Through Import of Abalones)

  • 박선일
    • 한국임상수의학회지
    • /
    • 제31권1호
    • /
    • pp.40-45
    • /
    • 2014
  • Abalone herpes-like virus (AbHV) is a fatal disease of abalones that impose severe economic impacts on the industry of infected regions due to high mortality. The aim of this study was to quantify the risk of introducing AbHV into Korea through the importation of live abalones for human consumption by import risk analysis (IRA). Monte Carlo simulation models were developed to provide estimates of the probability that a ton of imported abalone contains at least one AbHV-infected individual, using historical trade data and relevant literatures. A sensitivity analysis with 5,000 iterations was also conducted to determine the extent to which input parameters affect the outcome of the model. Although many uncertainties were present in the data, the results indicated that, if 5,000 tons of abalone were imported from a hypothetical exporting country with low prevalence of AbHV (model 1), there would be at least one AbHV-infected abalones in 4,816 of those tons (96.3%), while there would be at least one AbHV-infected abalones in 100% of those tons imported from country with high prevalence (model 2). Sensitivity analysis indicated that for model 1, prevalence was the strongest influence factor on the predicted number of infections. For model 2, background mortality and washing to reduce the risk of surface contamination during processing were the major contributing factors. Risk management strategies need to be enforced to reduce the risk of AbHV introduction in that at least one infected abalone would remain in a consignment from country even with a low prevalence of AbHV infection. The methodology and the results presented here will contribute to improve the development of AbHV management program, and with more accurate data this IRA model will aid science-based decision-making on mitigation strategies to reduce the risk of AbHV introduction in Korea.