• Annals of Clinical Neurophysiology
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• 제5권2호
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• pp.187-191
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• 2003

Purpose: MEPs elicited by transmagnetic stimulations of the motor cortex are facilitated by voluntary muscle contraction. We evaluated the effects of the imagination of the movements on latencies of MEPs and reciprocal inhibition by using transmagnetic stimulations. Methods: Twenty two healthy volunteers(eight men and fourteen women) were studied. TMSs were delivered at rest and during imagining abducting or adducting right thumb. A stimulator with a round coil and a fixed intensity of 80% of maximum was used to evoke MEPs. MEPs were evoked by magnetic stimulations over the scalp and cervical spine(C7-T1), and central motor conduction times(CMCT) were calculated by subtracting the latency of compound muscle action potentials(CMAPs) obtained by stimulating over the cervical spine from that obtained by stimulating over the scalp. The motor evoked potentials were recorded from right abductor pollicis brevis muscle(APB) and adductor pollicis muscle(AP) simultaneously. Results: Imagination of abduction resulted in a shortened latency of the CMAPs in APB, and a prolonged latency in AP. Imagination of adduction resulted in a shortened latency in AP, and a prolonged latency in APB. But the imagination caused no significant change in the latency of CMAPs elicited by stimulation over cervical spine. Therefore, the changes of the CMCTs account for these latency changes with imagination of movement. With the imagination of abduction, there are significant reduction of the CMCT's in APB(10.8%) and prolongation in AP(5.8%). On the other hand, with the imagination of adduction, prolongation of the CMCT's in APB(7.3%) and reduction in AP(5.9%) were observed. Conclusion: These findings indicate that imagination of muscle contraction increases the excitability of the human corticospinal system. Reciprocal inhibition may be accountable for the prolonged latency in the antagonist muscle.

• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2162-2172
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• 2020

Due to its computational efficiency and geometrical flexibility, the Method of Characteristics (MOC) has been widely used for light water reactor lattice physics analysis. Usually acceleration methods are necessary for MOC to achieve acceptable convergence on practical reactor physics problems. Among them, Coarse Mesh Finite Difference (CMFD) is very popular and can drastically reduce the number of transport iterations. In OpenMOC, CMFD acceleration was implemented but had the limitation of supporting only a uniform CMFD mesh, which would often lead to splitting MOC source regions, thus creating an unnecessary increase in computation and memory use. In this study, CMFD acceleration with a non-uniform Cartesian mesh is implemented into OpenMOC. We also propose a quadratic fit based CMFD prolongation method in the axial direction to further improve the acceleration when multiple MOC source regions are contained in one CMFD coarse mesh. Numerical results are presented to demonstrate the improvement of the CMFD acceleration capability in OpenMOC in terms of both efficiency and stability.

• 한국건설관리학회논문집
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• 제19권4호
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• pp.61-69
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• 2018

원도급계약에서의 공기연장 추가간접비에 대한 연구는 지속되어왔다. 그러나 하도급계약에서의 공기연장 추가간접비 산정방식에 대한 연구는 거의 없는 실정이다. 본 연구는 기존 현장에서 사용되고 있는 공기연장 추가간접비 산정방식과 선행연구에서 제안된 공기연장 추가간접비 산정방식에 대해 고찰하고 모형사례를 분석하여 산정방식을 비교하였다. S-curves형태의 간접비 발생을 반영한 모형사례의 발생상황을 사례별로 제시하여 선행연구에서 제시된 공기연장 추가간접비 산정방식별 산출결과를 비교하였다. 산정방식의 문제점을 고찰하는 과정에서 원사업자의 공기연장 추가간접비 산정방식으로 타당한 것으로 연구된 바 있는, 지연기간 평균실비산정방법이 수급사업자의 공기연장 추가간접비 산정에도 타당하다는 결론을 도출하여 보편적으로 적용될 수 있음을 입증하였다.

• 한국식품저장유통학회지
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• 제6권4호
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• pp.365-370
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• 1999

본 연구는 수확후 선도 저하가 빠른 쓰가루 사과의 선도연장 방법을 연구하기 위해 중앙흡인식 차압 예냉장치를 이용하여 수확후 바로 1$^{\circ}C$까지 품온을 낮추어 1$^{\circ}C$와 $25^{\circ}C$에서 각각 저장하여 각 처리구별로 호흡속도, 감모율 및 관능적 품질 변화 요인들을 비교.조사하였다. 사과를 1$^{\circ}C$까지 냉각시키는데 소요되는 시간은 차압예냉장치를 이용한 경우 박스의 형태 및 차압실 압력에 따라 5~6시간이 소요된 반면, 통기공이 없는 골판지 박스에 담아 1$^{\circ}C$ 저온저장고에 저장한 경우는 약 40시간 이상이 소요되었다. 호흡속도는 온도나 품온이 낮아짐에 따라 억제되었고, 저장기간이 경과할수록 계속 감소하였다. 예냉처리에 의하여 신선도가 연장되었는데 관능적 특성 변화는 외관보다는 조직감이나 맛 성분에 있어서 변화가 더 심하게 나타났고, 처리구간에 따라서는 비예냉구의 경우 $25^{\circ}C$에서 6일, 1$^{\circ}C$에서 21일이 지나면 상품성을 상실한 반면에 예냉구의 경우는 $25^{\circ}C$에서 9일, 1$^{\circ}C$에서 35일 후까지도 관능적으로 우수하였다.

• 한국식품저장유통학회지
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• 제14권2호
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• pp.113-118
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• 2007

LED (light smiling diode)를 가정용 냉장고에 부착하여 양배추의 선도 유지에 미치는 영향을 조사하였다. 가정용 냉장고에 부착된 LED의 조사가 저장 중 양배추의 품질변화에 미치는 가장 큰 효과는 엽록소 합성, 비타민 C 및 페놀성분의 함량 증가였다. LED가 부착된 냉장고에 저장된 양배추는 절단면이 흰색에서 녹색으로 변화하였으며, 따라서 절단면의 Hunter a값이 일반 냉장고에 저장된 양배추에 비해 현저히 낮은 수치를 나타내었다. 일반 냉장고$(4^{\circ}C)$에 10일간 저장된 양배추에 비해 LED가 부착된 냉장고에 저장된 양배추의 엽록소 함량이 4-6배정도 높았으며, LED조사 시 저장 중 비타민 C함량은 약 2배정도, 페놀성분의 함량은 14%정도 증가시켜 양배추의 영양성분을 증가시키는 효과가 있었다.

• The Korean Journal of Pain
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• 제32권4호
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• pp.256-263
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• 2019

Background: Antinociceptive anti-inflammatory drugs have many adverse effects. The goal of this investigation is to study the probable anti-inflammatory and analgesic effects of verapamil and N-acetylcysteine (NAC) in experimental rats. Methods: Adult male Wistar rats were randomly divided into 4 groups in the antinociceptive study, each containing 6 rats; the normal control group, which received saline (1 mL/kg); the diclofenac group, which received diclofenac sodium (5 mg/kg); the NAC group, which received NAC (125 mg/kg); and the verapamil group, which received verapamil (8 mg/kg). In the anti-inflammatory study, 5 groups were used, the 4 previous groups with the addition of an edema control group, received saline and were subjected to formalin test. Hot plate latency time was recorded for antinociceptive evaluation. Paw edema thickness and biochemical parameters were recorded for anti-inflammatory evaluation. Results: Administration of NAC showed significant prolongation of hot plate latency time at 1 hour when compared to the control group while verapamil showed a significant prolongation of hot plate latency time at 1 and 2 hours when compared to the control group and NAC group values. Administration of NAC and verapamil significantly decreased paw edema thickness at 2, 4, and 8 hours when compared to edema control values. Regarding biochemical markers, NAC and verapamil significantly decreased serum nitric oxide synthase, C-reactive protein, and cyclooxygenase-2 levels compared to the edema control value. In accordance, a marked improvement of histopathological findings was observed with both drugs. Conclusions: NAC and verapamil have antinociceptive and anti-inflammatory effects comparable to diclofenac sodium.

• 한국임상약학회지
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• 제33권4호
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• pp.242-253
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• 2023

Background: Arrhythmia due to QT prolongation is one of the most serious adverse events with drug interactions in the elderly. This study aimed to examine the incidence of arrhythmia in Korean elderly patients who administered both cytochrome P450 3A4 (CYP3A4) substrates and inhibitors. Methods: Patients using CYP3A4 substrate and inhibitor were selected from the 2017 elderly patient dataset (the Korean Health Insurance Review and Assessment Service - Aged Population Sample). Selection criteria were patients with a medication possession ratio over 80%, medication duration of at least 7 days, and a follow-up period of 3 months or more. The patient's basic information is age, gender, health insurance type, and comorbidities. The top 50 drug pairs and comorbidity with high-incidence arrhythmia were presented. Results: In patients with drug combinations for over 7 days, there were 981 incidences of arrhythmia, and 351 incidences in those with combinations for over 30 days. The comorbidities of congestive heart failure and myocardial infarction had a significant association with incidence of arrhythmia. Among patients with 7 days or longer, the drug pairs [substrates-inhibitors] with significant adjusted odds ratio (aOR) were [propranolol-cimetidine] (aOR, 2.25; 95% confidence interval [CI], 1.66-3.04). Among patients with 30 days or longer, the drug pairs with significant aOR were [tramadol-amiodarone] (aOR, 2.87; 95% CI, 1.97-4.19). Conclusions: In elderly patients, the incidence of arrhythmia was high with drug interactions of CYP3A4 substrates and inhibitors. The comorbidity of congestive heart failure was the risk factor.

• Archives of Pharmacal Research
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• 제11권3호
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• pp.240-243
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• 1988

The hexane extract from Nutmeg, the seed of Myristica fragrans significantly inhibited hepatic drug-metabolizing enzyme activity. Through systematic fractionation by $SiO_2$ column and vacuum liquid chromatography monitoring by bioassay, three components, myristicin, (I), licarin-B (II) and dehydrodiisoeugenol (III) were isolated as active principles. Compounds II and III, with a single treatment (200mg/kg, i.p.) showed not only a significant prolongation of hexobarbital-induced sleeping time but also a significant inhibition of aminopyrine N-demethylase and hexobarbital hydroxylase activities in mice. Compounds I and II provoked a sleep episode at a subhypnotic dose of HB, suggesting that they possess CNS-depressant properties.

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권4호
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• pp.142-144
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• 2004

To use Poly-dimethylsiloxane (PDMS) for the electrokinetic flow channel, the PDMS surface must be modified to be hydrophilic. With $O_2$ plasma treatment, it is difficult to maintain hydrophilicity for more than one day. In this paper, we present the chemical modification of the PDMS surface using 2-Hydroxyethyl methacrylate (HEMA) to prolong hydrophilicity lifetime. The oxide radicals generated temporarily on the PDMS surface by $O_2$ plasma are grafted with HEMA. Once the PDMS samples have been grafted, they demonstrate improved hydrophilicity retainment and electroosmotic flow characteristics compared to the untreated PDMS and the oxidized PDMS following the $O_2$ plasma process. This phenomenon was verified by the contact angles, Fourier transform infrared (FTIR) spectra and electro osmotic flow rates observed for more than 300 hours.

• Archives of Pharmacal Research
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• 제7권1호
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• pp.53-56
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• 1984

The effect of twenty two spices on liver microsomal monooxygense activity was tested as measured by alteration of hexobarbital (HB) narcosis and strychnine mortality in mice. Oral administration of seven spices for 7 consecutive days caused a significant shortening of the duration of HB-induced sleeping time. The treatment of mice with a single i. p. injection of 9 spices resulted in a significant prolongation of the sleeping time. White pepper, dill and fennel reduced the toxicity of strychnine. These results strongly indicated that some spices might affect the activity of liver microsomal drug metabolizing enzyme (DME) function.