• 한국환경농학회지
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• 제13권3호
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• pp.262-270
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• 1994

Endosulfan의 잔류분석(殘留分析)을 위한 RIA(radioimmuno assay)는 endosulfan alcohol(EA)-BSA conjugate를 항원(抗原)으로 하여 집토끼에서 면역항체(免疫抗體)를 생산(生産)하였다. 생산(生産)된 면역항체(免疫抗體)의 역가(力價)는 1 : 32,000 으로 endosulfan과 EA 이외(以外)의 유사화합물(類似化合物)에서는 거의 반응성(反應性)을 나타내지 않았으며 RIA를 위한 최적(最適) 희석배수(稀釋倍數)는 1 : 2,000 으로 나타났다. RIA의 최적(最適) 배양온도(培養溫度)는 $4\;^{\circ}C$ 이었으며 endosulfan의 검출범위(檢出範圍)는 $1\;ng-20\;{\mu}g$ 이었고 최소검출량(最小檢出量)은 1 ng 이었다. RIA 기법(技法)을 이용(利用)하여 잉어의 각(各) 조직(組織)과 공시수(供試水)에서 실시한 회수율(回收率) 시험(試驗) 결과(結果)는 GLC/ECD나 ELISA를 이용(利用)한 회수율(回收率)보다 우수하게 나타났다. 시료(試料)에서 RIA에 의한 endosulfan의 검출한계(檢出限界)는 0.1 ppb 였다.

• 한국작물학회지
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• 제30권1호
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• pp.47-52
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• 1985

Abscisin산(ABA)의 정량분석을 위한 방사면역 측정법을 개발하였다. ($\pm$)-ABA를 사람혈청 albumin에 conjugate 시킨 항원을 만들고 이를 가토에 접종하여 얻은 항혈청은 ABA에 대하여 높은 친화성을 나타냈다(Ka=3.28$\times$$10^{13}$$\ell$/mol ) $^3$H-ABA를 추적자로 사용하고 dextran-coated charcoal을 유리 ABA와 항체결합 ABA의 분리에 사용한 본 방사면역측정법은 ABA를 0.5$\times$$10^{-12}$mol 까지 측정할 수 있었고 측정범위는 14$\times$$10^{-12}$mol 까지 포함되었다. 이 면역측정법은 특이성이 높기 때문에 분석전 시료로부터 ABA를 미리 정제할 필요가 없었다. 시료 1개의 분석에는 2시간 정도 소요되어 하루 수백개의 시료률 분석처리할 수 있었다.

• Toxicological Research
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• 제11권1호
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• pp.23-29
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• 1995

Microsomes from human liver sample HL 110 oxidized aflatoxin $B_1$ $(AFB_1)$ to $AFB_1$ exo-8, 9-epoxide which was detected as a glutathione (GSH) conjugate with excess GSH S-transferase and to aflatoxin $Q_1$ ($AFB_1$; 3$\alpha$-hydroxyafiatoxin $B_1$), and testosterone to 6$\beta$-hydroxytestosterone. Anti-P450 3A4 nearly completely inhibited all of the reactions. Some fiavonoids inhibited all of the reactions. While other fiayonolds stimulated 8, 9-epoxidation and inhibited 3$\alpha$-hydroxylation. Gestodene inhibited all of the reactions when gestodene was metabolized by human liver microsomal P450 3A4 prior to adding substrate. But, ges-todene was added in the enzyme mixtures in the presence of $AFB_1$, it could not inhibit 8, 9-epoxidation of $AFB_1$. Nifedipine and troleandomycin inhibited both of the reactions of $AFB_1$ but only 3$\alpha$-hydroxylation was inhibited by the oxidation product of nifedipine. Although, troleandomycin was known as a mechanism-based inhibitor, the chemical did not show any detectable inhibitory effect on 6$\beta$-hydroxylation of testosterone. The results suggest that there are several different substrate-binding sites on P450 3A4.

• Pediatric Infection and Vaccine
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• 제19권3호
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• pp.89-110
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• 2012

Meningococcal Disease, manifesting as meningitis and septicemia, is a life-threatening bacterial infection that results in significant morbidity and mortality, particularly in childhood. Its epidemic potential and limited opportunities for clinical intervention due to its rapid course present unique public health and clinical challenges. Incidence is highest in infants and young children, with a secondary peak of risk in adolescents. Approximately 10% of cases are fatal and survivors can be left with serious and permanent sequelae including amputations, hearing loss and cognitive impairment. Transmission is only from human-to-human, by infected respiratory tract secretions or saliva and therefore crowding poses a tremendously elevated risk for disease development. Military recruits and university students are at high risk due to the high carriage rate in adolescents, their behavior patterns and close contact. Menveo$^{(R)}$ (Novartis Vaccines and Diagnostics), a novel quadrivalent meningococcal conjugate vaccine directed against meningococcal serogroups A, C, W-135 and Y, has been shown to be immunogenic and well tolerated in all age groups and was recently licensed for use in Korea. Recent cases and deaths among military recruits drew public attention to their elevated risk and the Korean government has recommended vaccination of all new military recruits. Many Korean students seek to attend school, university, or language institutes in countries where routine meningococcal vaccination is required - clinicians should be aware of such requirements to ensure that students are vaccinated prior to arrival in the destination country.

• 대한산업공학회지
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• 제16권2호
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• pp.135-147
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• 1990

A nuclear power plant can be viewed as a large complex man-machine system where high system reliability is obtained by ensuring that sub-systems are designed to operate at a very high level of performance. The chance of severe accident involving at least partial core-melt is very low but once it happens the consequence is very catastrophic. The prediction of risk in low probability, high-risk incidents must be examined in the contest of general engineering knowledge and operational experience. Engineering knowledge forms part of the prior information that must be quantified and then updated by statistical evidence gathered from operational experience. Recently, Bayesian procedures have been used to estimate rate of accident and to predict future risks. The Bayesian procedure has advantages in that it efficiently incorporates experts opinions and, if properly applied, it adaptively updates the model parameters such as the rate or probability of accidents. But at the same time it has the disadvantages of computational complexity. The predictive distribution for the time to next incident can not always be expected to end up with a nice closed form even with conjugate priors. Thus we often encounter a numerical integration problem with high dimensions to obtain a predictive distribution, which is practically unsolvable for a model that involves many parameters. In order to circumvent this difficulty, we propose a method of approximation that essentially breaks down a problem involving many integrations into several repetitive steps so that each step involves only a small number of integrations.

• 한국연소학회지
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• 제10권3호
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• pp.25-33
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• 2005

Fast-time instability is investigated for diffusion flames with Lewis numbers greater than unity by employing the numerical technique called the Evans function method. Since the time and length scales are those of the inner reactive-diffusive layer, the problem is equivalent to the instability problem for the $Li\tilde{n}\acute{a}n#s$ diffusion flame regime. The instability is primarily oscillatory, as seen from complex solution branches and can emerge prior to reaching the upper turning point of the S-curve, known as the $Li\tilde{n}\acute{a}n#s$ extinction condition. Depending on the Lewis number, the instability characteristics is found to be somewhat different. Below the critical Lewis number, $L_C$, the instability possesses primarily a pulsating nature in that the two real solution branches, existing for small wave numbers, merges at a finite wave number, at which a pair of complex conjugate solution branches bifurcate. For Lewis numbers greater than $L_C$, the solution branch for small reactant leakage is found to be purely complex with the maximum growth rate found at a finite wave number, thereby exhibiting a traveling nature. As the reactant leakage parameter is further increased, the instability characteristics turns into a pulsating type, similar to that for L < $L_C$.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.1002-1009
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• 2007

A rapid, convenient homogeneous competitive enzyme immunoassay for estimating the amount of fenthion is described. The assay utilizes glucose-6-phosphate dehydrogenase-hapten conjugates that are inhibited in solution by antibodies obtained from bovine serum albumin-hapten conjugates. In order to investigate the effects of bridging group recognition on the sensitivity of dose response characteristics, the bridging groups of varying alkyl chain length were attached at the phosphate position of fenthion. Among the antibodies used, the one obtained from the use of hapten (fenthion analog) with the same bridging group structure that was used in preparing the enzyme-fenthion conjugates showed maximum inhibition (up to 51.8%) in the absence of fenthion. In the presence of fenthion, the activity of the enzyme-hapten conjugate is regained in an amount proportional to the fenthion concentration. Under the optimized condition, the $ED_{50}$ value for fenthion was $0.809{\mu}g/ml$. The assay developed in this study is a rapid effective screening method for fenthion prior to precise analysis.

• The Journal of Asian Finance, Economics and Business
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• 제5권3호
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• pp.19-29
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• 2018

This research examined the alternatives of Jensen's alpha (α) estimation models in the Capital Asset Pricing Model, discussed by Treynor (1961), Sharpe (1964), and Lintner (1965), using the robust maximum likelihood type m-estimator (MM estimator) and Bayes estimator with conjugate prior. According to finance literature and practices, alpha has often been estimated using ordinary least square (OLS) regression method and monthly return data set. A sample of 50 securities is randomly selected from the list of the S&P 500 index. Their daily and monthly returns were collected over a period of the last five years. This research showed that the robust MM estimator performed well better than the OLS and Bayes estimators in terms of efficiency. The Bayes estimator did not perform better than the OLS estimator as expected. Interestingly, we also found that daily return data set would give more accurate alpha estimation than monthly return data set in all three MM, OLS, and Bayes estimators. We also proposed an alternative market efficiency test with the hypothesis testing Ho: α = 0 and was able to prove the S&P 500 index is efficient, but not perfect. More important, those findings above are checked with and validated by Jackknife resampling results.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권6호
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• pp.1635-1656
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• 2023

In Bayesian multi-target tracking, the Poisson multi-Bernoulli mixture (PMBM) filter is a state-of-the-art filter based on the methodology of random finite set which is a conjugate prior composed of Poisson point process (PPP) and multi-Bernoulli mixture (MBM). In order to improve the random finite set-based filter utilized in multi-target tracking of sensor scanning, this paper introduces the Poisson multi-Bernoulli mixture filter into time-matching Bayesian filtering framework and derive a tractable and principled method, namely: the time-matching Poisson multi-Bernoulli mixture (TM-PMBM) filter. We also provide the Gaussian mixture implementation of the TM-PMBM filter for linear-Gaussian dynamic and measurement models. Subsequently, we compare the performance of the TM-PMBM filter with other RFS filters based on time-matching method with different birth models under directional continuous scanning and out-of-order discontinuous scanning. The results of simulation demonstrate that the proposed filter not only can effectively reduce the influence of sampling time diversity, but also improve the estimated accuracy of target state along with cardinality.

• Toxicological Research
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• 제3권2호
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• pp.129-141
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• 1987

Hepatocytes isolated from rats which have been pretreated with phenobarbital (80 mg/kg for 3 days), were able to take up N-acetylcysteine from surrounding medium and were able to synthesize the reduced glutathione ($GSH^{\ast}-3$) intracellularly. The N-acetylcysteine is quickly deacetylated after the uptake and increases the pool size of cysteine, which was very low initially (5 nmol/$10^6$ cells). From this increased intracellular cysteine pool, GSH was synthesized. Freshly isolated rat hepatocytes contained a high level of GSH (30 nmol/$10^6$ cells), but upon incubation with the diethylmaleate, it was markedly decreased (10 nmol/$10^6$ cells). The hepatocytes with depleted GSH have lost viability upon incubations with acetaminophen (5mM) and paraquat (2 mM). However, when the N-acetylcysteine (1 mM) was added to this incubation condition, these chemical induced hepatocellular necrosis were prevented for longer durations. This N-acetylcysteine dependent protective effect against the hepatotoxic chemicals was lost by adding methionine sulfoximine (10 mM), an inhibitor of GSH biosynthesis. Both the carbontetrachloride (5 mM) and chioroform (5 mM) added to the incubation medium caused rapid losses of GSH and cell viability, even without the prior depletion of cellular GSH. However, again, if the 1mM N-acetylcysteine was supplemented, the rates of losses of GSH and cell viability were retarded in both cases. Even though large amounts of the added N-acetylcysteine was present in the cell, N-acetylcysteine conjugate of acetaminophen was not formed. Instead, only large amounts of GSH conjugate of the drug was produced. Thus, it is concluded that the added N-acetylcysteine is taken up and utilized for resynthesis of GSH. In turn, this resynthesized GSH contributes to the protection against cytotoxicity inducible with hepatotoxic drugs.