• Elastomers and Composites
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• 제52권2호
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• pp.105-113
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• 2017

The curing behavior, mechanical properties, hot-air aging resistance, abrasion properties,thermal properties, etc., of EVM/EPM/APP (ammonium polyphosphate)/DPER (dipentaerythritol)/EG (expandable graphite) and EVM/EPM/ATH (aluminium trihydroxide) flame retarding systems in ethylene vinyl acetate rubber (EVM) blends with EPM (ethylene propylene rubber) were sequentially examined. For both flame retarding systems, the torque values increased with the content of EPM rubber and with the vulcanization time. As the content of EPM rubber increased, the scorch time became shorter, whereas the optimum cure time followed an increasing trend. For the EVM/EPM/APP/DPER/EG flameretarding system, as the content of EPM rubber increased, the hardness did not change,whereas the tensile strength and elongation at break decreased. A hot-air aging resistance test at $150^{\circ}C$ showed that the heat resistance decreased with the EPM content regardless of the kinds and contents of flame retardants. As the EPM content increased, the abrasion rate became higher and the abrasion resistance of the EVM/EPM/APP/DPER/EG flame retarding systems exceeded that of the EVM/EPM/ATH flame retarding counterparts. In comparison with the EVM/EPM/ATH flame retarding systems, the thermal stability of the EVM/EPM/APP/DPER/EG flame retarding system showed an increasing tendency.

• 한국산업융합학회 논문집
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• 제3권1호
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• pp.77-82
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• 2000

The stereoselective ligand exchange reaction of trans-$[Co(SS-epm)Cl_2]^+$ and racemic propane-1,2-diamine (rac-pn) produces the complex that is identified as $[CO(N)_6]^{3+}$ type of $[Co(SS-epm)(pn)]^{3+}$ by absorption spectrum. It is conceivable that the reaction mechanism involves substitution and isomerization. The calculated and experimentally determined ratios of the complexed enantiomeric substrates at equilibrium were as follows: $[Co(SS-epm)(pn)]^{3+}$,calcd 32 % / 68 %, exptl 19 % / 81 % R-pn / S-pn. It has been shown that the employment of molecular mechanics calculations as a predictive tool may lead to the design of chiral complexes that may be applied to the separation of racemic mixtures of simple bidentate ligands.

• 대한안전경영과학회지
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• 제10권2호
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• pp.133-141
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• 2008

The need for total enterprise management that covers from accepting orders, design, cost, procurement, manufacture, and delivery has been recently raised in order for efficient project management of small and medium size plant construction enterprises. This trend is reflected in the introduction of EPM(Enterprise Project Management) solutions by some shipbuilding enterprises and large construction corporations. In step with the trend, small and medium size plant construction enterprises are enabled to provide knowledge base in terms of reducing cost and production period and managing portfolio for accepting orders and attaining contract by inducing customized EPM This study presents a design of customized EPM based on a case study of a company. It exhibits a collaborative/collaboration resource-supply model which can be universally applied to small and medium size job-order production enterprises. The research discusses that under the assumption that information is shared internally between departments on planning, supply, manufacture, and quality control in order to create collaborative environment and close participation is created externally between suppliers and orderers, productivity can be improved in cost reduction through planning efficient collaborative supply model.

• Elastomers and Composites
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• 제25권2호
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• pp.97-102
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• 1990

국내에서 생산, 혹은 수입 시판되고 있는 11종류의 EPDM과 1종의 EPM고무에 대한 선형점탄성적 성질을 RDS로 측정하였다. 측정은 $210^{\circ}C$에서 등온적으로 행하였으며. 이들 고무의 복합점도, 저장탄성계수, 손실탄성계수, 손실 tangent 및 완화스팩트럼 data는 고무 블렌딩이나, 복합화과정에서 중요한 자료로 이용될 것으로 믿는다.

• Journal of Korean Neurosurgical Society
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• 제59권2호
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• pp.161-164
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• 2016

Few preoperative extrapontine myelinolysis (EPM) cases with pituitary adenoma have been reported. No such case had long follow-up to see the outcome of EPM. We reported a 38-year-old man complaining of nausea, malaise and transient loss of consciousness who was found to have severe hyponatremia. Neurologic deficits including altered mental status, behavioral disturbances, dysarthria and dysphagia developed despite slow correction of hyponatremia. Endocrine and imaging studies revealed hypopituitarism, nonfunctional pituitary macroadenoma and extrapontine myelinolysis. Transsphenoidal surgery was performed after three weeks of supportive therapy, when neurological symptoms improved significantly. The patient recovered function completely 3 months after surgery. Our case indicates that outcome of EPM can be good even with prolonged periods of severe neurologic impairment.

• Advances in Traditional Medicine
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• 제9권2호
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• pp.135-141
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• 2009

The purpose of this study was to characterize the putative anxiolytic-like effects of the 70% ethanol extract of Portulaca oleracea (EPO) using an elevated plus maze (EPM) in mice. The EPO was orally administered at 50, 100, 200 or 400 mg/kg to ICR mice, 1 h before the behavioral evaluation in the EPM, respectively. Control mice were treated with an equal volume of 10% tween 80, and positive control mice with diazepam (1 mg/kg). Single treatments of the EPO significantly increased the percentage of time spent and arm entries into the open arms of the EPM versus controls (P < 0.05). Moreover, there were no changes in the locomotor activity and myorelaxant effects in any group compared with the saline controls. In addition, the anxiolytic-like effects of the EPO were blocked by flumazenil (10 mg/kg, i.p), a $GABA_A$ antagonist not by WAY 100635 (0.3 mg/kg, i.p), a 5-$HT_{1A}$ receptor antagonist. These results indicate that P. oleracea is an effective anxiolytic agent, and suggest that the anxiolytic-like effects of P. oleracea is mediated via the GABAergic nervous system.

• 생명과학회지
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• 제24권3호
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• pp.290-296
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• 2014

이 연구의 목적은 mice를 이용하여 elevated plus-maze (EPM) test와 hole-board test를 통해 quercetin의 잠재적인 항불안 작용을 확인하고자 함이다. Quercetin을 1.25, 2.5, 5나 10 mg/kg의 용량으로 각각 행동시험을 측정하기 1 시간 전에 ICR mice에 경구투여하였다. 대조군은 동일한 양의 10% Tween 80을 투여하였고 양성대조군으로 buspirone 2 mg/kg을 투여하였다. Quercetin을 단회 투여하여 EPM test를 실시한 결과, 5 mg/kg 용량에서 open arm에 머문 시간 및 진입한 횟수의 백분율이 control group과 비교하여 통계적으로 유의성 있게 증가하였다(p<0.05). 또한 quercetin을 투여하여 hole-board test를 실시한 결과, 5 mg/kg 용량에서 구멍에 머리를 넣은 횟수가 control group과 비교하여 통계적으로 유의성 있게 증가하였다(p<0.05). 또한 quercetin와 flumazenil ($GABA_A$ antagonist), WAY-100635 ($GABA_{A-{\rho}}$ antagonist) 또는 trans-4-aminocrotonic acid ($GABA_{A-{\rho}}$ agonist)를 병용투여하여 elevated plus-maze를 실험을 하여 신경계와의 관계를 확인한 결과, trans-4-aminocrotonic acid에서만 quercetin의 항불안 작용이 차단되었음을 확인 할 수 있었다. 결론적으로, 본 연구의 결과에서 quercetin이 elevated plus-maze 및 hole-board test, horizontal wire test, open field test를 통하여 locomotor activity 및 근육이완이나 진정 등의 부작용이 없으면서 우수한 항불안 작용을 가지는 소재라고 생각되며 이러한 작용이 특히 GABA 신경계와 관련이 있음을 시사하고 있다.

• Korean Journal of Radiology
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• 제25권2호
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• pp.212-213
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• 2024

• 대한한방부인과학회지
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• 제26권4호
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• pp.14-29
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• 2013

목 적: 본 연구는 갱년기 우울증 모델에서 사물탕가향부자(SGH)의 항우울 효능 및 면역반응에 대한 실험적 유의성을 확인함으로써 임상적인 응용에 기초자료로 사용하기 위하여 시행되었다. SGH가 반복적인 스트레스를 가한 난소적출 흰쥐에서 항우울행동 효과와 estradiol level 및 anti-inflammatory cytokine인 IL-4에 미치는 영향을 연구하고자 하였다. 방 법: 난소적출 흰쥐에 2주간 반복적인 스트레스를 주고 동시에 SGH(200 and 400 mg/kg/day)를 경구 투여한 후 행동검사인 Elevated Plus Maze(EPM)를 통한 우울행동과 혈청 estradiol, IL-4의 변화를 측정하였고, 또한 뇌 내 Locus coeruleus(LC)와 Paraventricular Nucleus(PVN)에서 IL-4의 변화를 측정하였다. 결 과: 1. EPM에서 SGH 400 mg 투여군은 대조군에 비해서 open arms에 머무는 시간이 현저히 증가하였고, closed arms에 머무는 시간이 현저히 감소하였다. 2. EPM에서 SGH 투여군은 대조군에 비해서 open arms와 closed arms를 교차하는 횟수가 증가하였으나, 통계적인 유의성은 없었다. 3. Estradiol 측정에서 SGH를 투여한 후 estradiol 수준이 현저하게 증가하였다. 4. IL-4 측정에서 SGH를 투여한 후 혈청 IL-4 수준이 현저하게 증가하였다. 5. 뇌에서의 IL-4 면역반응은 대조군에서 감소하였으나, SGH를 투여한 후 LC와 PVN에서 IL-4 수준의 유의성 있는 변화는 나타나지 않았다. 결 론: 이상의 결과로 사물탕가향부자는 난소적출 흰쥐의 항우울행동과 면역조절에 유효함을 알 수 있었다.

• Biomolecules & Therapeutics
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• 제13권2호
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• pp.84-89
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• 2005

The purpose of this study was to characterize the putative anxiolytic-like effects of the aqueous extract of the root of Polygala tenuifolia ( AEPT) using an elevated plus maze (EPM) and hole-board apparatus in mice. The AFPT was orally administered at 50, 100, 200 or 400 mg/kg to ICR mice, 1 h before the behavioral evaluation in the EPM respectively. Control mice were treated with an equal volume of saline, and positive control mice with buspirone (2 mg/kg). Single treatments of the AEPT significantly increased the percentage of time spent and arm entries into the open arms of the EPM vedrsus saline controls (P<0.05). Moreover, there were no changes in the locomotor activity and myorelaxant effects in any group compared with the saline controls. In the hole-board test,single treatments of the AEPT (200 and 400 mg/kg) significantly increased the number of headdips versus saline controls (P<0.05). In addition, the anxiolytic-like effects of the AEPT were blocked by WAY 100635(0.3mg/kg, I.p), a5-$HT_{1A}$ receptor antagonist not by flumazenil, a $GABA_{A}$ antagonist. These results indicate that P. tenuifolia is an effective anxiolytic agent, andsuggest that the anxiolytic-like effects of P. tenuifolia is mediated via the serotonergic nervous system.