• Molecules and Cells
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• 제20권2호
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• pp.235-240
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• 2005

Extracts of pine needles (Pinus densiflora Sieb. et Zucc.) have diverse physiological and pharmacological actions. In this study we show that pine needle extract alters pacemaker currents in interstitial cells of Cajal (ICC) by modulating ATP-sensitive $K^+$ channels and that this effect is mediated by prostaglandins. In whole cell patches at $30^{\circ}C$, ICC generated spontaneous pacemaker potentials in the current clamp mode (I = 0), and inward currents (pacemaker currents) in the voltage clamp mode at a holding potential of -70 mV. Pine needle extract hyperpolarized the membrane potential, and in voltage clamp mode decreased both the frequency and amplitude of the pacemaker currents, and increased the resting currents in the outward direction. It also inhibited the pacemaker currents in a dose-dependent manner. Because the effects of pine needle extract on pacemaker currents were the same as those of pinacidil (an ATP-sensitive $K^+$ channel opener) we tested the effect of glibenclamide (an ATP-sensitive $K^+$ channels blocker) on ICC exposed to pine needle extract. The effects of pine needle extract on pacemaker currents were blocked by glibenclamide. To see whether production of prostaglandins (PGs) is involved in the inhibitory effect of pine needle extract on pacemaker currents, we tested the effects of naproxen, a non-selective cyclooxygenase (COX-1 and COX-2) inhibitor, and AH6809, a prostaglandin EP1 and EP2 receptor antagonist. Naproxen and AH6809 blocked the inhibitory effects of pine needle extract on ICC. These results indicate that pine needle extract inhibits the pacemaker currents of ICC by activating ATP-sensitive $K^+$ channels via the production of PGs.

• 해양환경안전학회지
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• 제28권spc호
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• pp.11-17
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• 2022

본 논문에서는 해상 위험유해물질(Hazardous Noxious Substances, HNS) 사고의 효과적인 대응을 위해 개발된 부유식 무인이동체기반 광역탐지 및 모니터링 시스템의 운용 시나리오 설계와 실험 검증 내용을 보인다. 광역탐지 및 모니터링 시스템은 장시간 운용이 가능하되 제한적 이동이 가능한 무계류형 부이 형태를 갖는 부유식 무인이동체 플랫폼을 기반으로 개발되었으며 임무 수행에 필요한 열화상 카메라, 레이더, 부유 및 대기 HNS의 탐지를 위한 센서가 탑재되었다. 실험 검증 과정에서는 탐지 센서 성능을 야외 환경에서 실험적으로 검증하기 위해 이동식 가스 유출 시스템(Portable Gas-exposure System, PGS)을 추가로 설치하였다. 무인 시스템의 원격 및 자율 운용을 위해 전체 운용 소프트웨어는 로봇운영체제(Robot Operating System, ROS) 프레임워크를 기반으로 통합되었다. 내수면 및 실해역에서의 실험을 통해 개발된 시스템의 운용 및 활용 가능성을 실험적으로 검증하였다.

• Clinical and Experimental Reproductive Medicine
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• 제25권1호
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• pp.25-33
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• 1998

Cyclooxygenase (COX) is an enzyme involved in the conversion of arachidonic acid to prostaglandins (PGs), and exists in two forms, COX-1 and COX-2. COX has been reported to be involved in early implantation by secretion of PGs which causes permeability of vessels and reaction of decidual cells around the implantation site. Recently, in mice and sheep studies, COX-1 and COX-2 expression in the endometrium has been reported to be different according to implantation and stages of the estrous cycle, but expression of COX-1 and COX-2 in human endometrium during the menstrual cycle has not yet been established. The purpose of this study was to observe the variances of COX-1 and COX-2 expression by immunohistochemical staining in endometrial samples obtained from human hysterectomy specimens and biopsies of women of reproductive age according to different stages of the menstrual cycle. Also, we attempted to observe COX-1 and COX-2 expression in the epithelial and stromal cells of the endometrium obtained during the mid-secretory phase, which were cultured separately. COX-2 showed a cyclic pattern of expression according to the different stages of the menstrual cycle and was strongly expressed particularly at the mid-secretory phase which corresponds to the time of implantation. However, COX-1 tended to be increased in the early proliferative, and mid- and late secretory phases, but was also expressed in the whole menstrual cycle showing no particular pattern. In the separately cultured cells COX-1 was expressed in epithilial cells and COX-2 in the stromal cells. The above results suggest that since COX-2 is expressed at the same time as implantation and cultured cells display a specific secretory pattern, COX-2 has inductive endocrine enzyme properties and has an important effect on endometrial cells during implantation. Also, COX-2 expression in endometrial cells may be utilized as a useful marker of endometrial maturation.

• 한국식생활문화학회지
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• 제5권4호
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• pp.443-448
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• 1990

The object of this study was to investigate the characteristics of pectinesterase(PE), polygalacturonase(PG) and Peroxidase(POD) in Kimchi materials. The results were as follows : 1. The specific activities of PEs in Korean cabbage, Korean raddish, garlic and ginger were 200 unit/mg protein, 23.1 unit/mg protein, 0.8 unit/mg protein and 32 unit/mg protein, respectively. The optimum pHs of PEs in all materials were between 7 to 8. The concentrations of NaCl, $CaCl_2$ which showed the highest activities of PEs were $0.2{\sim}0.3M$ NaCl, 50 mM $CaCl_2$ in Korean cabbage and raddish, 0.05 M NaCl, 20 mM $CaCl_2$ in garlic and 0.2 M NaCl, 20 mM $CaCl_2$ in ginger. 2. The specific activities and the optimum pHs of PGs were 1.5 unit/mg protein and pH 4.5 in Korean cabbage, 1.6 unit/mg protein and $pH\;4.5{\sim}5.5M$ in Korean raddish, 0.06 unit/mg protein and $pH\;3.0{\sim}3.5M$ in garlic, and 0.06 unit/mg protein and $CaCl_2$ in ginger. The concentrations of NaCl, $CaCl_2$ which showed the highest activities of PGs were $0.1{\sim}0.2M$ NaCl and $0.15{\sim}0.2mM$ mM $CaCl_2$ in all materials. 3. The specific activities and the optimum pHs of PODs in Korean cabbage, Korean raddish, garlic and ginger were 71.3 unit/mg protein ; pH 6.0. 769 unit/mg protein ; pH 5.5, 1.09 unit/mg protein ; pH 4.5 and 12.7 unit/mg protein ; $pH\;5.0{\sim}5.5M$, respectively. POD activities were not decreased in Korean cabbage, but decreased in Korean raddish by the increase of NaCl, $CaCl_2$ concentrations. In garlic and ginger, POD activities were a little slightly affected by the increase of NaCl, $CaCl_2$ concentrations.

• Journal of Ginseng Research
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• 제13권1호
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• pp.66-70
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• 1989

홍미삼엑기스의 일부 성분이 내삼투압성 효모인 C. parapsilosis의 생육에 미치는 영향을 조사하기 위하여 홍미삼엑기스로부터 유기용매로 이행되는 일부 성분군을 분리 추출하여 그 조성을 조사하고 각 성분군이 C. parapsilosis의 증식에 미치는 영향을 조사하였다. 균증식은 헥산 가용성 물질(Fr.A)에 의하여 현저한 억제작용을 받았고 Fr.A와 조사포닌이 동시에 혼재하면 다소 회복되기는 하였으나 PGS(대조구) 배지에서 보다는 낮았다. 에텔 가용성 물질(Fr.B) 및 에틸아세테이트 가용성 물질(Fr.C)은 현저한 균증식 촉진효과가 있었고 Fr.B 혹은 Fr.c와 조사포닌이 동시에 혼재하면 세포 증식속도가 더욱 촉진되어 Fr.B와 조사포닌 그리고 Fr.C와 조사포닌은 상승적 촉진작용을 하였으며 셀룰로오스 투석막 외액(Fr.E)도 생육을 촉진하였으며 조사포닌과 함께 상승적 촉진작용을 하였다. 조사포닌은 단독으로 존재할 때 균생육에 큰 영향을 미치지 않았으나 다른 성분과 함께 상승적 촉진작용을 하는 특성이 있어 단일 ginenoside 수준에서의 균생육에 미치는 영향이 검토되어야 할 것으로 생각된다.

• 대한전자공학회논문지TC
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• 제39권12호
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• pp.559-565
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• 2002

현재 RFIC를 위해 실리콘 기판상에 구현되는 인덕터의 Q 값은 12 이하로 알려져있기 때문에, 고성능 회로설계를 위해서는 더욱 높은 Q 값을 갖는 인덕터의 구현이 필수적이다. 본 논문에서는 본드와이어를 이용하여 높은 Q 값을 가지는 두 개의 인덕터를 제안하였고, 동일한 인덕터에 PGS를 적용하여 총 4가지 형태의 인덕터를 구현하였다. 제안된 본드와이어 인덕터는 일반적인 금속선로보다 넓은 단면적 때문에 상대적으로 작은 도체 손실을 갖고, 인덕터의 상당부분이 공기 중에 위치하므로 기생 캐패시턴스 성분을 줄일 수 있다. 해석 및 측정결과 1.5 GHz 에서 기존의 나선형 인덕터보다 상당히 개선된 15이상의 Q 값을 가짐을 확인하였다. 또한 자동 본딩 머신을 사용하여 구현하기 때문에, 동일한 형태의 인덕터를 반복적으로 쉽게 만들 수 있다.

• BMB Reports
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• 제42권7호
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• pp.401-410
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• 2009

We have developed a targeted lipidomics approach that makes it possible to directly analyze chiral eicosanoid lipids generated in cellular systems. The eicosanoids, including prostaglandins (PGs), thromboxanes (TXs), leukotrienes (LTs) and alcohols (HETEs), have been implicated as potent lipid mediators of various biological processes. Enzymatic formations of eicosanoids are regioselective and enantioselective, whereas reactive oxygen species (ROS)-mediated formation proceeds with no stereo-selectivity. To distinguish between enzymatic and non-enzymatic pathways of eicosanoid formation, it is necessary to resolve enantiomeric forms as well as regioisomers. High sensitivity is also required to analyze the eicosanoid lipids that are usually present as trace amounts (pM level) in biological fluids. A discovery of liquid chromatography-electron capture atmospheric pressure chemical ionization/mass spectrometry (LC-ECAPCI/MS) allows us to couple normal phase chiral chromatography without loss of sensitivity. Analytical specificity was obtained by the use of collision-induced dissociation (CID) and tandem MS (MS/MS). With combination of stable isotope dilution methodology, complex mixtures of regioisomeric and enantiomeric eicosanoids have been resolved and quantified in biological samples with high sensitivity and specificity. Targeted chiral lipidomics profiles of bioactive eicosanoid lipids obtained from various cell systems and their biological implications have been discussed.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.503-504
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• 2006

This paper presents the design and fabrication of a LC voltage-controlled oscillator (VCO) using 1-poly 6-metal mixed signal CMOS process. To obtain the high-quality factor inductor in LC resonator, patterned-ground shields (PGS) is placed under the symmetric inductor to reduce the effect from image current of resistive Si substrate. Moreover, due to the incapability of using thick top metal layer of which the thickness is over $2{\mu}m$, as used in many RF CMOS process, the structure of dual-metal layer in which we make electrically short circuit between the top metal and the next metal below it by a great number of via materials along the metal traces is adopted. The circuit operated from 2.63 GHz to 3.09 GHz tuned by accumulation-mode MOS varactor. The corresponding tuning range was 460 MHz. The measured phase noise was -115 dBc/Hz @ 1MHz offset at 2.63 GHz carrier frequency and the current consumption and the corresponding power consumption were about 2.6 mA and 4.68 mW respectively.

• 약학회지
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• 제42권2호
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• pp.214-219
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• 1998

Tissue distributions and association of cyclooxygenase-2 (COX-2) with inflammatory have led us to search for COX-2 selective inhibitors from natural products. Conceptually, COX- 2 selective inhibitors should be expected to retain anti-inflammatory efficacy by inhibition of PGs production while reducing or eliminating the gastric, renal and hemostatic side effects commonly associated with NSAIDs use. Thus, a logical approach to the treatment of inflammatory diseases should involve the inhibitors of COX-2. To develop new COX-2 inhibitors from natural products, two hundred crude drugs were screened by inhibiting PGD2 generation in bone marrow derived mast cells (BMMC). Among them, 6 methanol extracts of crude drugs such as, Bletillae rhizoma, Aconiti kgreani rhizoma, Belamcandae rhizoma, Nelumbinis semen, Gleniae radix, Aurantii immatri pericarpium inhibited more than 85% of BMMC COX-2 activity at a concentration 2.5${\mu}$g/ml.

• Journal of Electrical Engineering and Technology
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• 제8권4호
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• pp.920-929
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• 2013

Within the project 'e performance' supported by the German Ministry of Education and Research (BMBF) an electric vehicle, powered by two lithium-ion battery packs of different capacity and voltage has been developed. The required Energy Management System (EMS) in this system controls the current flows of both packs independently by means of two individual dc-dc converters. It acts as an intermediary between energy storage (battery management systems-BMS) and the drivetrain controller on the vehicle control unit (VCU) as well as the on-board charger. This paper describes the most important tasks of the EMS and its interfaces to the BMS and the VCU. To validate the algorithms before integrating them into the vehicle prototype, a detailed Matlab / Simulink-model was created in the project. Test procedures and results from the simulation as well as experiences and comparisons from the real car are presented at the end.