• 제목/요약/키워드: bell

검색결과 1,029건 처리시간 0.025초

Regulatory Action of $\beta-adrenergic$ Agonist and 8-bromocyclic AMP on Calcium Currents in the Unfertilized Mouse Eggs

  • Haan, Jae-Hee;Cheong, Seung-Jin;Kim, Yang-Mi;Park, Choon-Ok;Hong, Seong-Geun
    • The Korean Journal of Physiology
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    • 제27권2호
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    • pp.175-183
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    • 1993
  • There are many report suggesting that influx and intracellular calcium concentration $([Ca^{2+}]_i)$ are related to cell signalling in various cells. However, it has not been reported that calcium channel activation is affected by the substances involved in signal transduction pathways in the mouse eggs. In this study, the effects of isoprenaline (ISP) and cyclic AMP on calcium influx through calcium channels were investigated to show their relationship with the signal transduction process in unfertilized mouse eggs. Using whole cell voltage clamp techniques, calcium currents, elicited by the depolarizing pulses of 300 ms duration (from -50 mV to 50 mV in 10 mV increments) from a holding potential of -80 mV, were recorded. The current-voltage (I-V) relation of calcium currents was shown to be bell-shaped; the current began to activate at -50 mV and reached its maximum $(-1.33{\pm}0.16\;nA:\;mean{\pm}S.E.,\;n=7)$ at -10 mV, then decayed at around 50 mV. Calcium currents were fully activated within $7\;ms{\sim}20\;ms$ and completely inactivated 200 ms after onset of the step pulse. ISP within the concentration ranges of $10^{-8}\;M{\sim}10^{-4}\;M$ dose-dependently increased the amplitude calcium current. The permeable cyclic AMP analogue,8-bromocyclic AMP, also increased its maximal amplitude by 46ft at $10^{-5}\;M$, while protein kinase inhibitor (PKI), which is known to inhibit 0.02 phosphorylating units of cyclic AMP-dependent protein kinase (PKA) per microgram decreased calcium currents. Currents recorded in the presence of PKI were resistant to increase by the application of $10^{-5}\;M$. Also, PKI inhibited the calcium current increase elicited by ISP treatment. These results suggest that $\beta-adrenergic$ regulation of the calcium channel is mediated by the cAMP-dependent protein kinase. This signal transduction pathway might play a role in regulating $[Ca^{2+}]_i$, level due to the increase of calcium influx in mouse eggs.

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양초 연소 시 발생되는 오염물질 방출계수 측정을 위한 연소실 제작과 평가 (Evaluation of the combustion chamber for burning candle and measuring the emission factor of its’ combustion products)

  • 임형진;김만구
    • 분석과학
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    • 제28권3호
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    • pp.236-245
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    • 2015
  • 최근 실내 분위기 환경조성이나 차 등의 가열용으로 실내에서 양초가 많이 사용되고 있다. 이 연구에서는 0.008 m3 벨쟈를 이용하여 소형 연소실을 제작하고, 양초 연소 생성물들의 방출계수를 측정하였다. 연소실 내부에 유리 접시를 양초 위에 설치하여 불꽃의 직접적인 영향을 배제하고 배출구의 높이를 높이고 깔때기 모양으로 하여 배출구로 유입되는 외기를 차단하여 균질한 조성의 배출가스를 얻을 수 있었다. 연소실 배출가스의 온도는 34 ℃~41 ℃의 범위였다. 양초 연소 시 발생하는 연소생성물은 주로 알데하이드류나 산류등 함 산소화합물들이었다. 양초 연소생성물의 질량단위방출계수는 벤젠, 톨루엔, 에틸벤젠이 각각 0.04 μg/g, 0.01 μg/g, 0.02 μg/g 이었으며, 총휘발성 유기 화합물의 방출계수는 3.81 μg/g으로 나타났다. 알데하이드류의 방출계수는 폼알데하이드, 아세트알데하이드 및 벤즈알데하이드가 각각 4.48 μg/g, 1.09 μg/g, 0.67 μg/g으로 VOC 류 보다 높은 방출계수를 나타냈다. 실험에서 사용된 양초 시료의 성분의 차이점을 고려하면 이 연구에서 사용한 0.008 m3 연소실을 이용하여 얻은 연소생성물들의 질량단위 방출계수와 기존의 0.17 m3~50 m3 연소실을 이용해 측정한 결과들과 매우 유사하였다.

가정내 응급처치를 위한 민간요법 (Folk Remedies for First Aid at Home)

  • 강현숙;조결자
    • 동서간호학연구지
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    • 제3권1호
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    • pp.17-26
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    • 1998
  • The purposes of this study were to identify the contents, frequency of use, and the rationales of folk remedies frequently used for first aid at home for stomachache, vomiting, strain, food poisoning, vaginal bleeding, or wounds of snake or dog bite, or bee sting. As the method of the study, data were collected by conducting a questionnaire of 185 persons, who filled it out or who were interviewed from May to August in 1998. The collected data was analyzed by using frequency and the rationales for the contents of the folk remedies were described base on literatures. The results were as follows,. 1. The folk remedies for stomachache in frequency order were 'warming the abdomen', 'rubbing the abdomen with a hand', or 'pricking a finger to bleed', which have the rationals. 2. The folk remedies for vomiting in frequency order are 'drinking water of watery radish' and 'pricking a finger to bleed', which have the rationales. 3. The folk remedies for strain in frequency order are 'soaking the affected area into cold water or applying an ice pack' and 'after soaking jasmine in water, making a dough with flour, and then attaching it on the affected area', which have the rationales, Additionally, although the frequencies are low, 'drinking brewed Achyranthis Radix' and 'applying brewed leaves and stalks of Sambuci Cortex' have the rationales. 4. The folk remedies for food poisoning in frequency order are 'drinking black beans and licorice brewed together' and 'eating mung beans', which have the scientific grounds. 5. The folk remedies for bloody discharge in frequency order are 'drinking brewed lotus root' and 'eating boiled chicken stuffed with root of bell-flower'. However, 'drinking brewed Thujae orientalis Folium' has the rationales. 6. The folk remedy for snake bite wounds that has the scientific grounds is 'sucking blood by a person without hurt in the mouth'. However, quite a lot of people apply alum or soy paste, which has no rationales. 7. The folk remedies for the bee sting in frequency order are 'after removing the sting, applying soy paste or sauce' and 'applying saliva'. No rationales for 'applying saliva' have been found. 8. The folk remedy for the dog bite wound that has the rationales is 'applying juice of leaves or stalks of Xanthii Fructus'. However, 85% of surveyed people use remedies that have no scientific grounds, such as 'applying burnt dog hair mixed with (sesame) oil' and 'applying soy paste or sauce'. Various materials are used in folk remedies for first aid treatment as shown above. Some of the folk remedies have the rationales since their medicinal actions have been found. However, the medicinal actions of the majority have not been found, but only known that they are effective, Especially for the materials except botanical drugs, they are used without knowing the effects since their components and pharmacognosies have not been described in any literature. The results of this research may be used for materials to educate the surveyed people or to consult them. Accordingly, the folk remedies that have the rationales are required to continue to study to find out the effects.

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고도 보정용 확장-굴절(E-D) 노즐의 국외 연구 동향 (Research Trends of an E-D Nozzle for Altitude Compensation)

  • 문태석;박상현;최준섭;허환일
    • 한국항공우주학회지
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    • 제45권10호
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    • pp.844-854
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    • 2017
  • E-D 노즐은 고도에 따라 노즐 내의 유효 면적을 변화시켜 고도 보정 효과를 통해 성능 이득을 가지는 노즐이다. E-D 노즐은 노즐의 길이를 절감시켜 발사체의 탑재중량이득을 얻을 수 있다고 알려져 있는데, 이러한 E-D 노즐의 장점과 잠재적인 가능성 때문에 영국, 독일, 호주, 유럽 등에서 관련된 연구가 수행되었다. 영국의 경우 E-D 노즐의 유동 특성과 고도 보정 노즐 중 듀얼 벨 노즐과의 성능 비교 연구를 수행하였고, DLR에서는 E-D 노즐의 천이 특성을 파악하기 위해 노즐 압력비 변화에 따른 천이 특성을 중점적으로 분석하였다. 유럽에서는 실제 발사체 Ariane 5 ESC-B 상단에 E-D 노즐 개념을 적용한 수치적 연구를 수행하여 노즐 길이 절감에 따른 탑재중량이득 가능성을 확인하였다. 본 논문에서는 국외에서 수행한 E-D 노즐의 연구 동향을 특징 별로 분류 및 분석하였고, 향후 E-D 노즐 연구의 기초 자료로 활용하고자 한다.

수직원통형 빙축열조내 외향용융과정시 열전달특성에 관한 연구 -작동유체의 유동방향 및 축열조 형상비에 따른 열성능 비교- (A study on the heat transfer characteristics during outward melting process of ice in a vertical cylinder)

  • 김동환;김동춘;김일경;김영기;임장순
    • 설비공학논문집
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    • 제9권2호
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    • pp.171-179
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    • 1997
  • During the day time in summer, peak of air conditing load, and electric power management system lies under overloaded condition. The reason is the enlarged peak load value of electric power caused by increased air-cooling load in summer. To prevent load concentration during day time and overloaded condition of power management system, some energy storage methods are suggested. One of these methods is ice storage system. Water has some good properties as P.C.M.(Phase Chang Material) : Its melting point is the range of required operation temperature. It has large specific latent heat and is chemically stable compared to other organic or inorganic substances. It is cheap and easy to treat. This study represents experimental results of heat transfer characteristics of P.C.M. under the outward melting process in a vertical cylinder. We experimented with twelve combinations of conditions, i.e., three different inlet temperatures($7^{\circ}C,\;4^{\circ}C\;and\;1^{\circ}C$), two working fluid directions(upward and downward), and two aspect ratios, H/R(4 and 2). At the inlet temperature of $7^{\circ}C$ and $4^{\circ}C$, there was temperature stagnation region where the temperature of P.C.M. remains constant at $4^{\circ}C$ regardless of aspect ratio and direction of working fluid. This temperature stagnation occurs as the water, at its maximum density, flows down to the lower region. The phase change interface formed bell-shaped curve as the melting process continued. With a new set of conditions(4H/R, inlet temperature $4^{\circ}C$ and $1^{\circ}C$, downward/upwerd inlet direction), the movement of phase change interface was faster when the working flued inlet direction was downward. With the same set of conditions, melting rate and total melting energy were larger when the working fluid inlet direction was downward. The results were reversed when the other sets of conditions were applied.

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콘텐트 중심 네트워크에서 정규표현식을 활용한 캐시친화적인 적응형 스트리밍 프레임워크 (Cache-Friendly Adaptive Video Streaming Framework Exploiting Regular Expression in Content Centric Networks)

  • 손동현;최대진;최낙중;송정환;권태경
    • 한국통신학회논문지
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    • 제40권9호
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    • pp.1776-1785
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    • 2015
  • 인터넷을 이용하는 사용자의 관점이 호스트 중심에서 콘텐트 중심으로 변화하면서 콘텐트 중심 네트워크 (Content Centric Network, 이하 CCN)라는 새로운 패러다임이 소개되었다. 한편, 최근 비디오 스트리밍에 대한 수요가 급증하고 있으며 더 높은 사용자의 만족도를 위한 적응형 스트리밍이 소개되면서 많은 연구가 진행 중에 있다. 따라서 CCN에서도 사용자의 수요에 따라 적응형 스트리밍을 고려할 필요성이 있다. 하지만 CCN에서 기존의 네트워크 구조에서와 동일한 방식으로 적응형 비디오 스트리밍 서비스를 할 경우 CCN 라우터 내 캐시를 (CS) 충분히 활용하지 못한다는 한계점이 있으며 또한 단말의 달라지는 요구 사항을 캐시 활용에 반영할 수 없는 문제점도 있다. 따라서 본 논문에서는 정규표현식을 활용한 콘텐트 네이밍 방식을 적용하여 기존 적응형 스트리밍 비트레이트 선택 알고리즘의 캐시활용도를 높이면서도 CCN의 기본 프로토콜에 적합한 프레임워크를 제시하고, 단말의 상태에 따라 동적인 표현식 기술 전략 및 선택 알고리즘을 통하여 비디오 스트리밍 품질을 개선하고자 한다.

안이비인후피부과 외래환자의 임상적 분석 (A Clinical Analysis of Ophthalmology, Otorhinolaryngology & Dermatology)

  • 정순영;서형식
    • 한방안이비인후피부과학회지
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    • 제18권2호
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    • pp.51-61
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    • 2005
  • We analyzed statistics study in 1394 patients, who had visited to the Dept. of dermatology, ophthalmology & otorhinolaryngology Hospital of Oriental Medicine Sangji University from July, 2003 to December, 2004. The results were as follows. 1. Distribution of ophthalmology, otorhinolaryngology and dermatology classification was 14.23% in ophthalmology, 13.92% in rhinology, 4.79% in laryngology, 23.05% in dermatology, 8.25% in otology, 2.14% in stomatology and 33.63% in other. 2. Ophthalmology group were 12.39% males and 14.16% females in 61years old over. In treatment term, opthalmology patients who had treated for 2 weeks within were 85.84%. Blepharism and asthenopia were the most common ophthalmologic disease. 3. Rhinology group were 18.10% males in 11-20 years old and 14.48% females in 10 years old within. In treatment term, rhinology patients who had treated for 2 weeks within were 70.59%. Rhinitis and sinusitis were the most common rhiniologic disease. 4. Otology group were 19.08% males and 16.80% females in 61years old over. In treatment term, otologic patients who had treated for 2 weeks within were 64.89%. Tinnitus and vertigo were the most common otologic disease. 5. Laryngology group were 10.53% males and 17.11% females 41-50 years old. In treatment term, laryngology patients who had treated for 2 weeks within were 85.53%. pharyngitis and abnormal pharyngolarylgeal region sensation were the most common laryngologic disease. 6. Stomatology group were 11.76% males in 31-40, 41-50 years old and 17.65% females in 61 years old over. In treatment term, stomatology patients who had treated for 2 weeks within were 82.35%. Stomatitis and labium spasm were the most common stomatologic disease. 7. Dermatology group were 11.75% males and 15.30% females in 21-30 years old. In treatment term, dermatology patients who had treated for 2 weeks within were 72.95%. Acne and urticaria were the most common dermatologic disease. 8. Other group were 8.99% males in 41-50 years old and 14.04% female in 61 years old over. In treatment term, other group patients who had treated for 2 weeks within were 69.29%. Bell's palsy and common cold were the most common other disease.

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Altered Expression of RANKL/OPG after Alendronate Administration in the Developing Teeth of Postnatal Rats

  • Kim, Min-Ju;Jun, Yun-Jeong;Yu, Hong-Il;Yang, So-Yeong;Oh, Won-Man;Kim, Sun-Hun;Kim, Min-Seok
    • International Journal of Oral Biology
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    • 제36권1호
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    • pp.37-42
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    • 2011
  • The working mechanism of bisphosphonate on bone cells is unclear despite its powerful inhibitory activity on bone resorption. The differentiation and activation of osteoclasts are essential for bone resorption and are controlled by the stimulatory RANKL and inhibitory OPG molecules. Teeth exhibit a range of movement patterns during their eruption to establish their form and function, which inevitably accompanies peripheral bone resorption. Hence, the mandible, which contains the teeth during their eruption processes, is a good model for revealing the inhibitory mechanism of bisphosphonate upon bone resorption. In the present study, RANKL and OPG expression were examined immunohistochemically in the mandible of rats with developing teeth after alendronate administration (2.5 mg/kg). The preeruptive mandibular first molars at postnatal days 3 to 10 showed the developing stages from bell to crown. No morphological changes in tooth formation were observed after alendronate administration. The number of osteoclasts in the alveolar bone around the developing teeth decreased markedly at postnatal days 3, 7 and 10 compared with the control group. RANKL induced strong positive immunohistochemical reactions in the dental follicles and stromal cells around the mandibular first molar. In particular, many osteoclasts with strongly positive reactions to RANKL appeared above the developing mandibular first molars at postnatal days 3 and 10. Immunohistochemical reactions with RANKL after alendronate administration were weaker than the control groups. However, the immunohistochemical reactivity to OPG was stronger after alendronate administration, at postnatal days 3 and 10. These results suggest that alendronate may decrease bone resorption by regulating the RANKL/OPG pathway in the process of osteoclast formation, resulting in a delay in tooth eruption.

전자부품의 냉각을 위한 자연대류 상관 관계식의 평가

  • 이재헌
    • 기계저널
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    • 제27권6호
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    • pp.504-514
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    • 1987
  • 복잡한 전자부품의 조립시에 필요한 열적 디자인에 관한 정보는 오래전부터 실험을 통하여 얻어지고 있다. 실험적 데이터를 이용하여 무차원 파라미터로 표시된 실험결과는 꼭 같지는 않지만 현상적으로는 비슷한 상황에 응용될 수 있다. 여기서는 학술문헌에 나타나 있는 자연대류에 관한 실험적인 상관관계식들과 프레임에 수직으로 꽂혀있는 균일가열 전자회로기판의 모델에서 얻어진 무차원 자료들을 비교하고자 한다. 대부분의 자료들은 수정채널 Rayleigh수(Ra")가 15~100범위에 속하며, 이러한 범위는 부품이 조밀하게 배치된 기관이 서로 좁은 채널을 이루고 있으며, 동시에 상당한 전력을 소비하고 있는 경우에 해당한다. Wirt와 Stutzman, Bar-Cohen과 Rohsenow의 일반상관관계식은 AT'||'&'||'T Bell 연구소에서 개발된 전자기기를 이용하여 수집한 실험데이터를 잘 표현하고 있으며 10 < Ra" <1,000범위에서 추천될 수 있다. 두개의 유사한 상관관계식과 비교할 때 상당히 좋은 예측을 보였으며 또한 Sparrow와 Gregg의 연구결과와도 잘 일치하므로 Ra" < 10인 경우에 Aung의 완전발달층류의 채널유동방식, Ra" > 1,000인 경우에는 Aung등의 단일 수직평판 근사식이 추천될 수 있다. Coyne의 알고리즘에 의한 계산치는 10

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모더니즘 미술비평에 있어서 '자율성' (Autonomy)의 문제 (A Matter of Autonomy in Art Criticism on Modernism)

  • 최광진
    • 조형예술학연구
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    • 제3권
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    • pp.87-144
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    • 2001
  • This study looks into historical genealogy of autonomy in art criticism on modernism and presents the view of the judgment and correction about that. A matter of autonomy in art appeared in the attempt to totally reconsider and upset the theory of 'Mimesis' or 'Representation' which was the basis of traditional aesthetic theory. In the traditional theory of representation, they assumed primary image exists first and then tried to obtain visual similarity to it through art works. However, in the theory of autonomy in modernism, they maintained the reduction to pure form' or medium', regarding what art works represents and how similar to primary image are not the true essence of art. In the early 20th century, C. Bell laid the foundation stone of the theory of Formalism', providing that a matter of autonomy is significant form', which is the combination of lines and colors Aesthetic autonomy theory came to a climax by C. Greenberg, who systemized art criticism on modernism in the middle 20th century. According to his theory, the pursuit of the essence of form resulted in the specificity of medium' and flatness. They thought that the autonomy of art would be achieved by eliminating outward social factors from art works. This theory ended by Minimalism preventing the instructive function of art work and only emphasizing its material property. Since the middle 20th century, the autonomy theory was confronted with the limit and intense attack because it resulted in this fixed canon and materialism, so they began laying emphasis on those extrinsic factors around art works such as human life, society, history, and so on. This study focuses on arguing and complementing the limit of autonomy such as the adhesive and fixed canon, and then defining the more dynamic area of it. For this, first, I introduced the view of T. J. Clark and T. Crow who criticized the aesthetic autonomy theory. They denied the transcendental structure of form, and found form only in the association with substantial life and society. And they insisted the dynamism of form by emphasizing form as a result of negation insisted by avant-garde. Second, I researched the view of A. C, Danto and M. Fried, who complemented the traditional autonomy theory. They made autonomy emerge from the fixation of form like flatness through connecting essentialism with historical view. In conclusion, I insist that autonomic position of art make it possible to connect or mediate between material form and human or social elements. Therefore, autonomy should not be reduced to the axis of form or that of society but make interaction between two heterogeneous axes.

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