• 아태비즈니스연구
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• 제10권4호
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• pp.87-118
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• 2019

The purpose of this study is to examine the effects of person-job fit, which consists of educational fit and skill fit, on employees' intrinsic job satisfaction. To the end, the 10-year balanced panel data of the Korean Labor and Income Panel Study(KLIPS) by the Korea Labor Institute (KLI) for 2008-2017 are utilized. This study analyzes 12,730 observations by 1,273 employees by using fixed effect model, random effect model, and pooled OLS estimation method. The empirical results are as follows: First, it is founded that educational fit and skill fit seem affect job satisfaction positively. Second, the negative effects of over-education are clear and the negative effects of under-education are unclear, while the effects of over-skilled and under-skilled are insignificant statistically. Third, the results imply that the size of effect of over-education on intrinsic job satisfaction is larger than that of the effect of over-skilled. Forth, it is shown that the use of fixed effect model is more effective and trustworthy than that of random effect model and pooled OLS estimation method, implying that the effect size of coefficients which are estimated by pooled OLS method and random effect model are likely over-estimated. The empirical results above imply that firms and employees should focus on solving over-education issue before all in order to enhance employees' job satisfaction and it is needed to monitor regularly whether systemic job assignment process is done based on the employees' educational attainment and skill level and to provide more chances for job re-allocation and job rotation.

• 한국미생물·생명공학회지
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• 제52권2호
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• pp.141-151
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• 2024

Isochrysis sp. is a sea microalga that has become a species of interest because of the extreme lipid content and rapid growth rate of this organism indicating its potential for efficient biofuel production. Using genome sequencing/genome-scale modeling for the prediction of Isochrysis sp. metabolic utilities there is high scope for the identification of essential pathways for the extraction of byproducts of interest at a higher rate. In our work, we design and present iIsochr964, a genome-scale metabolic model of Isochrysis sp. including 4315 reactions, 934 genes, and 1879 metabolites, which are distributed among fourteen compartments. For model validation, experimental culture, and isolation of Isochrysis sp. were performed and biomass values were used for validation of the genome-scale model. OptFlux was instrumental in uncovering several novel metabolites that influence the organism's metabolism by increasing the flux of interacting metabolites, such as Malonyl-CoA, EPA, Protein and others. iIsochr964 provides a compelling resource of metabolic understanding to revolutionize its industrial applications, thereby fostering sustainable development and allowing estimations and simulations of the organism metabolism under varying physiological, chemical, and genetic conditions. It is also useful in principle to provide a systemic view of Isochrysis sp. metabolism, efficiently guiding research and granting context to omics data.

• 한국임상약학회지
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• 제18권2호
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• pp.84-96
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• 2008

In the recent, pharmacokinetic (PK)/pharmacodynamic (PD) modeling has appeared as a critical path tools in new drug development to optimize drug efficacy and safety. PK/PD modeling is the mathematical approaches of the relationships between PK and PD. This approach in new drug development can be estimated inaccessible PK and PD parameters, evaluated competing hypothesis, and predicted the response under new conditions. Additionally, PK/PD modeling provides the information about systemic conditions for understanding the pharmacology and biology. These advantages of PK/PD model development are to provide the early decision-making information in new drug development process, and to improve the prediction power for the success of clinical trials. The purpose of this review article is to summarize the PK/PD modeling process, and to provide the theoretical and practical information about widely used PK/PD models. This review also provides model schemes and the differential equations for the development of PK/PD model.

• 대한수의학회지
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• 제37권2호
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• pp.291-299
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• 1997

In order to establish optimal dosage schedules and withdrawal times for sulfamethazine(SMZ) in pigs, pharmacokinetic and tissue distribution experiments were conducted in pigs. For comparative purposes, tissue depletion kinetics are also studied in rats. From three pigs administered with SMZ i.v., the pharmacokinetic profile of SMZ in two pigs was adequately described by a one-compartment open model whereas that in one pig was patterned after a two-compartment open model. Volume of distribution(Vd) was 0.48~0.57 L/kg and biological half-life($t_{1/2}$) was 11.8-16.8 h. From three pigs dosed with SMZ p.o., pharmacokinetic profile was explainable with a one-compartment open model. Time to reach maximum SMZ concentration in serum (Tmax) was 2.8 h, 3.2 h and 7.5 h. Elimination half-life was 2.8-7.5 h. The descending order in concentration of SMZ was plsama > kidney > liver > lung > heart > pancreas > spleen > duodenum > ileum > brain > adipsoe tissue from three pigs sacrificed at 5h, 29h and 54h after the administration of SMZ, p.o.. The protein binding of SMZ in pigs was 55.2%($2.5{\mu}g/ml$), 71.5% ($5{\mu}g/kg$) and 71.5%($10{\mu}g/ml$). The mean systemic bioavailability (F) of SMZ p.o. was 49.1 %. Meanwhile the pharmacokinetic profile of SMZ in rats was adequately described by a one-compartment open model. Absorption of SMZ p.o. in the rat was very rapid. In conclusion, the oral optimal dosage regimen of SMZ for pigs was the initial dose of 45.7 mg/kg followed by the maintenance dose of 30.2 mg/kg for high specific pathogens to SMZ. The time to reach below the stipulated residual allowable concentration (0.1 ppm) was calculated 93 h after oral administration of 200 mg/kg recommended by manufactureres.

• IMMUNE NETWORK
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• 제5권1호
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• pp.36-44
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• 2005

Background: The anti-tumor therapeutic effect of autologous tumor cell lysate pulseddendritic cells (DCs) was studied for non-immunogenic and immune suppressive lung cancer model. To test the possibility as an adjuvant therapy, minimal residual disease model was considered in mouse in vivo experiments. Methods: Syngeneic 3LL lung cancer cells were inoculated intravenously into the C57BL/6 mouse. Autologous tumor cell (3LL) or allogeneic leukemia cell (WEHI-3) lysate pulsed-DCs were injected twice in two weeks. Intraperitoneal DC injection was started one day (MRD model) after tumor cell inoculation. Two weeks after the final DC injection, tumor formation in the lung and the tumor-specific systemic immunity were observed. Tumor-specific lymphocyte proliferation and the IFN-${\gamma}$ secretion were analyzed for the immune monitoring. Therapeutic DCs were cultured from the bone marrow myeloid lineage cells with GM-CSF and IL-4 for 7 days and pulsed with tumor cell lysate for 18 hrs. Results: Compared to the saline treated group, tumor formation was suppressed in 3LL tumor cell lysate pulsed-DC treated group, while 3LL-specific immune stimulation was minimum. WEHI-3-specific immune stimulation occurred in WEHI-3 lysate-pulsed DC treated group, which had no correlation with tumor regression. Conclusion: The data suggest the possible anti-tumor effect of cultured DCs as an adjuvant therapy for minimal residual disease state of lung cancer. The significance of immune modulation in DC therapy including the possible involvement of NK cell as well as antigen-specific cytotoxic T cell activity induction was discussed.

• 한국산학기술학회논문지
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• 제7권3호
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• pp.518-523
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• 2006

본 논문은 하이브리드 의사결정 나무(CART)와 인공신경망 모델을 개발하여 고객의 이탈에 대한 예측을 높이기 위하여 가정방문 학습지 고객의 패턴을 분류하고, 분석하는 새로운 방법에 대하여 연구하였다. 의사 결정나무(CART5)를 형성하여 선택된 결정변수들은 인공신경망의 입력벡터 값으로 선택되는 새로운 방법을 제시하였다. 고객 관리측면에서 본 논문은 가정방문 학습지 회사의 기존고객을 분류하여 패턴을 분석함으로써 우수한 고객의 지속적인 관리와 이탈 가능성이 많은 고객을 차별 관리하여 기업이익을 증대시킬 수 있을 것이다. 새롭게 제안한 하이브리드 모델은 기존의 의사결정트리모델(CART), 회귀모형, 인공신경망 모델과 비교한 결과 그 예측 정확성이 높음을 확인할 수 있었다.

• 대한예방한의학회지
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• 제5권2호
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• pp.93-105
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• 2001

BACKGROUND : Changiga is a hetnal medicine which has been used of the traditional therapeutic agent of asthma. So I examine the effect of Changija on immune Cell&serum OA-specific IgE in BALF in rat asthma model. MATERIAL and METHODS : Rats were sensitized with OA; at day 1 sensitized group and Changiga(CIG) groups were systemically immunized by subcutaneous ingection of 1mg OA and 300mg of Al(OH)3 in a total volume of 2ml. At the same time, 1ml of 0.9% saline containing $6{\times}109$ B. pertussis bacilli was injected by i.p. 14 days, after the systemic immunization, rats received local immunization by inhaling 0.9% saline aerocol containing 2%(wt/vol) OA, A day after local immunization, BAL fluid was collected from the rats. A day after local immunization, rats were orally administered with Changiga extract 14 days, Lymphocyte, CD4+ T-cell CD8+ T-cell counts, CD4+/CD8+ ratio in BALF, change of serum OA-specific IgE level in the peripheral blood were measured and evaluated. RESULT : Changiga showed a suppressive effect on a rat asthme model. Changiga decreased lymphocyte, CD4+ T-cell, CD4+/CD8+ ratio in BALF, serum OA-specific IgE level as compared with the control group, whereas Changiga decreased CD8+ T-cell in BALF with statistical nonsignificance as compared with the control group. CONCLUSION: This study shows that Changiga have a suppressive effect on rat allergic athma model. Changiga would be useful allergic asthma treatment agent.

• 대한의용생체공학회:의공학회지
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• 제36권5호
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• pp.183-190
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• 2015

Invasive blood pressure (IBP) is measured for the patient's real time arterial pressure (ABP) to monitor the critical abrupt disorders of the cardiovascular system. It can be used for the estimation of cardiac output and the opening and closing time detection of the aortic valve. Although the unexplained inflections on ABP make it difficult to find the mathematical relations with other cardiovascular parameters, the estimations based on ABP for other data have been accepted as useful methods as they had been verified with the statistical results among vast patient data. Previous windkessel models were composed with systemic resistance and vascular compliance and they were successful at explaining the average systolic and diastolic values of ABP simply. Although it is well-known that the blood pressure reflection from peripheral arteries causes complex inflection on ABP, previous models do not contain any elements of the reflections because of the complexity of peripheral arteries' shapes. In this study, to simulate a reflection wave of blood pressure, a new mathematical model was designed with four elements that were the impedance of aorta, the compliance of aortic arch, the peripheral resistance, and the compliance of peripheral arteries. The parameters of the new model were adjusted to have three types of arterial blood pressure waveform that were measured from a patient. It was used to find the relations between the inflections and other cardiovascular parameters such as the opening-closing time of aortic valve and the cardiac output. It showed that the blood pressure reflection can bring wide range errors to the closing time of aortic valve and cardiac output with the conventional estimation based on ABP and that the changes of one-stroke volumes can be easily detected with previous estimation while the changes of heart rate can bring some error caused by unexpected reflections.

• KIEAE Journal
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• 제11권3호
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• pp.63-68
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• 2011

Building deterioration would be proceeded by various causes such as physical, social, economic degradation. The deterioration would be inevitably prevented or delayed to get the decent function and performance in various building part and components. The maintenance and management are continued to provide the decent living condition for the household. The maintenance means mainly a repair, including the on-time and longterm plan. The longterm repair would be conducted by the systemic preparation in management activity and a required cost. Therefore, the annual due for the longterm repair plan is important to prepare the repair cost in a required time. In this paper, it aimed at analyzing the longterm repair cost and modelling to forecast the required cost in total area, number of household and time elapse in apartment housing. The estimation model of a repair cost is used with a power function which has a good statistics. Results of this study are shown that the sample has a longterm repair due in a $2,032won/m^2{\cdot}yr$ averagely which is higher than $912won/m^2{\cdot}yr$ in domestic. Second, the longterm repair due is proportionally correlated with the time elapse in both a total area and the number of household. Third, the estimation model for the longterm repair amount is suitable for the power function which is most in any other estimation models. Fourth, the ration of the longterm plan repair due a year to the cumulated longterm amount is about 26%.

• Biomolecules & Therapeutics
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• 제25권3호
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• pp.259-265
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• 2017

This study aimed to investigate the analgesic effect of substance P (SP) in an animal model of neuropathic pain. An experimental model of neuropathic pain, the chronic constriction injury (CCI) model, was established using ICR mice. An intravenous (i.v.) injection of SP (1 nmole/kg) was administered to the mice to examine the analgesic effects of systemic SP on neuropathic pain. Behavioral testing and immunostaining was performed following treatment of the CCI model with SP. SP attenuated mechanical allodynia in a time-dependent manner, beginning at 1 h following administration, peaking at 1 day post-injection, and decaying by 3 days post-injection. The second injection of SP also increased the threshold of mechanical allodynia, with the effects peaking on day 1 and decaying by day 3. A reduction in phospho-ERK and glial fibrillary acidic protein (GFAP) accompanied the attenuation of mechanical allodynia. We have shown for the first time that i.v. administration of substance P attenuated mechanical allodynia in the maintenance phase of neuropathic pain using von Frey's test, and simultaneously reduced levels of phospho-ERK and GFAP, which are representative biochemical markers of neuropathic pain. Importantly, glial cells in the dorsal horn of the spinal cord (L4-L5) of SP-treated CCI mice, expressed the anti-inflammatory cytokine, IL-10, which was not seen in vehicle saline-treated mice. Thus, i.v. administration of substance P may be beneficial for improving the treatment of patients with neuropathic pain, since it decreases the activity of nociceptive factors and increases the expression of anti-nociceptive factors.