• 한국콘텐츠학회논문지
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• 제7권6호
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• pp.99-106
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• 2007

본 연구는 다매체 다채널 시대를 맞아 국내 주요 5개 방송사의 뉴스 시청자는 어떤 유형의 사람들이며 그들은 어떤 이유에서 특정 채널의 뉴스를 선택하는지를 규명하고자 실시되었다. 이 연구는 4개의 TV 뉴스 콘텐츠의 채널 선택 유형(channel loyalty type, brief news type, central watcher type, peripheral watcher type)을 귀납적으로 측정, 채널 선택 유형에 따른 인구통계학적 특성과 채널 선택 특성 등을 밝히는데 목적이 있다. 연구 결과 'brief news' type이 가장 높은 비율을 차지해 생활 패턴의 변화와 뉴스시청 행위가 밀접한 관계가 있음을 알 수 있다. 또 뉴스 채널 선택 유형에 따라 성(性)과 연령, 직업 등 인구통계학적 특성이 나타났다. 아울러 방송사별로 시청자들의 채널 선택 유형에 나름대로 특징이 있는 것으로 분석됐다. 즉 KBS1은 'central watcher', MBC는 'channel loyalty', SBS는 'peripheral watcher', YTN은 'brief news' type이 특징적으로 나타났고 KBS2는 뚜렷한 특징이 없는 것으로 분석됐다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1703-1708
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• 2004

In this study, we are investigated experimentally the pumping characteristics about the pumping channel shapes of disk-type drag pump (DTDP). We are experimented the pumping performance about the rotors which have channel or do not exist. The channel disk-type rotor has spiral channels both upper and lower part, and stator is planar. The planar disk-type rotor hasn't channel and stator has spiral channels both upper and lower part. The flow-meter method is adopted to calculate the pumping speed. Compression ratio and pumping speeds for the nitrogen gas are measured under the inlet pressure range of 0.001 ${\sim}$ 4 Torr. The maximum of compression ratio was about 3300 for three-stage DTDP (channel disk-type rotor), 1000 for four-stage (planar disk-type rotor) and two-stage DTDP (channel disk-type rotor) at zero throughput. The ultimate pressure was $1.6{\times}10^{-6}$ Torr for three-stage DTDP (channel disk-type rotor), $2.5{\times}10^{-6}$ Torr for four-stage DTDP (planar disk-type rotor).

• Animal cells and systems
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• 제3권1호
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• pp.53-58
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• 1999

The immunocytochemical method was used to identify the existence of voltage-dependent $Ca^{2＋}$-channels in mouse follicular oocytes. Three types of voltage-dependent $Ca^{2＋}$-channels were shown to exist in the follicular oocytes for the first time, the P/Q-type $Ca^{2＋}$-channel, the N-type $Ca^{2＋}$-channel, and the L-type $Ca^{2＋}$-channel. Among proven $Ca^{2＋}$-channels distributions of the P/Q-type $Ca^{2＋}$-channel and L-type $Ca^{2＋}$-channel showed localized staining (clustered pattern) on the oolemma. The distribution of the P/Q-type $Ca^{2＋}$-channel showed all localized staining, and the range of localized staining was from 1 to 8 in staining intensity. As the staining intensity increased from 1 to 8, the number of localized staining decreased. The L-type $Ca^{2＋}$-channel are homogeneously stained (29.4%-54.2%), while some of them (around 28.7%-44.1%) showed localized staining on the oolemma. However, the rest of them showed no staining at all (17.1%- 26.5%). On the contrary, the N-type $Ca^{2＋}$-channel showed mostly homogeneous staining, while nonstaining oocytes were around 33.8%. The rest showed localized staining (10%). However, staining intensity was much weaker than those of the P/Q-type and L-type $Ca^{2＋}$-channel. In fact, the N-type $Ca^{2＋}$-channel has been known to exist only in neurons (from ectoderm origin), but it is unknown how the N-type $Ca^{2＋}$-channel exists in the follicular oocytes (from mesoderm origin). Further studies are needed to examine the expression of $Ca^{2＋}$-channels during the developmental stages of the oocytes.

• Clinical and Experimental Reproductive Medicine
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• 제28권1호
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• pp.13-24
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• 2001

Objective: In muscle and neuronal cells, calcium channels have been classified by electrophysiological and pharmacological properties into (1) voltage-dependent $Ca^{2+}$-channel (1) P/Q-type $Ca^{2+}$-channel (2) N-type $Ca^{2+}$-channel (3) L-type $Ca^{2+}$-channel (4) T-type $Ca^{2+}$-channel (5) R-type $Ca^{2+}$-channel. The present study was done in order to investigate whether there is any difference in $Ca^{2+}$-channel distribution between activated and normally fertilized embryos. Methods: The immunocytochemical method was used to identify the existence of voltage-dependent $Ca^{2+}$-channels in parthenogenetically activated 2-cell embryos by ethanol and $SrCl_2$ treatment. These 2-cell embryos were obtained by exposure to 6% ethanol for 6 min and to 10 mM $SrCl_2$ for 2h. Results: P/Q-type $Ca^{2+}$-channels and L-type $Ca^{2+}$-channels have been identified. Whereas, three type of $Ca^{2+}$-channel P/Q-type, N-type, L-type have been identified in 2-cell embryos fertilized in vivo. Conclusion: Activation by ethanol was faster than those by $SrCl_2$. However, there was difference in DAB staining of the embryos between ethanol and $SrCl_2$ treatment (87.7% and 54.1 %). Intensity of staining was also different between ethanol- and $SrCl_2$-treated group. However, it has not been known why there was some difference in DAB staining and staining intensity in the present study.

• 한국안전학회지
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• 제19권3호
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• pp.78-83
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• 2004

The channel-type lining board that partial welded on many partition frames is used to normal servicing lining board type. On this study is to investigate existing channel-type lining board's capacity by using the static loading test. From this study, to develop new-type lining board which reflect well cross section area and sectional modulus of existing channel-type lining board. Six types FEM model are adopted. The accumulated test results of stress conditions and deflections by section shapes will be used to analyzed the relation between the capacity and the section shape. With the comparing the results of static loading test and FEM analysis.

• Journal of Ginseng Research
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• 제24권1호
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• pp.18-22
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• 2000

앞의 연구에서 우리는 진세노사이드가 신경세포에 존재하는 high-threshold voltage-dependent $Ca^{2+}$ channel을 억제한다는 것을 발표하였다. 그러나, 이러한 연구는 진세노사이드가 여러 칼슘 채널subtypes중 어느 특정 칼슘 채널만을 선택적으로 조절한다는 것을 보여주지는 않았다. 따라서 이 연구에서 우리는 여러 칼슘 채널subtypes에 선택적으로 작용하는 약물 혹은 toxins을 이용하여 진세노사이드가 어느 종류의 칼슘 채널 subtypes를 억제하는가를 bovine chromaffin cell을 이용하여 연구하였다. 사용한 물질은nimodipine(L-type 칼슘 채널 길항제), $\omega$-conotoxin GVIA (N-type $Ca^{2+}$ channel 길항제), $\omega$-agatoxin IVA(P-type 칼슘 채널 길항제)이었다. 연구 결과 진세노사이드는 bovine chromaffin 세포에 존재하는 high-threshold 칼슘 current을 투여 농도별로 억제하였다. $IC_{50}$/은 약 120 $\mu$g/ml인 것으로 나타났다. nimodipine은 진세노사이드에 의한 칼슘 currents억제 작용에 영향을 미치지 않은 것으로 나타났다. 그러나, $\omega$-conotoxin GVIA, $\omega$-agatoxin IVA 및 nimodipine+$\omega$-conotoxin GVIA+$\omega$-agatoxin IVA을 처리한 세포에서는 진세노사이드에 의한 칼슘 currents억제 작용이 현저하게 줄어 들었다. 이러한 연구 결과들은 진세노사이드가 L-type 칼슘 채널은 억제하지 않고, 주로 N-, p-, 및 Q-type칼슘 채널을 억제한다는 것을 보여주고 있다

• The Korean Journal of Physiology and Pharmacology
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• 제16권1호
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• pp.25-30
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• 2012

Under some pathological conditions as bile flow obstruction or liver diseases with the enterohepatic circulation being disrupted, regurgitation of bile acids into the systemic circulation occurs and the plasma level of bile acids increases. Bile acids in circulation may affect the nervous system. We examined this possibility by studying the effects of bile acids on gating of neuronal (N)-type $Ca^{2+}$ channel that is essential for neurotransmitter release at synapses of the peripheral and central nervous system. N-type $Ca^{2+}$ channel currents were recorded from bullfrog sympathetic neuron under a cell-attached mode using 100 mM $Ba^{2+}$ as a charge carrier. Cholic acid (CA, $10^{-6}M$) that is relatively hydrophilic thus less cytotoxic was included in the pipette solution. CA suppressed the open probability of N-type $Ca^{2+}$ channel, which appeared to be due to an increase in (no activity) sweeps. For example, the proportion of sweep in the presence of CA was ~40% at +40 mV as compared with ~8% in the control recorded without CA. Other single channel properties including slope conductance, single channel current amplitude, open and shut times were not significantly affected by CA being present. The results suggest that CA could modulate N-type $Ca^{2+}$ channel gating at a concentration as low as $10^{-6}M$. Bile acids have been shown to activate nonselective cation conductance and depolarize the cell membrane. Under pathological conditions with increased circulating bile acids, CA suppression of N-type $Ca^{2+}$ channel function may be beneficial against overexcitation of the synapses.

• 유통과학연구
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• 제13권5호
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• pp.91-102
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• 2015

Purpose - This study aims to build a systematic frame for effective marketing performances by prioritizing product type and pertinent channel that are appropriate for digital channel characteristics. FCB grid model was used to define a product type, and Internet communication satisfaction index was considered as a marketing performance measuring tool for digital channel. Research design, data, and methodology - As systematic understanding for Digital marketing is still unfamiliar to even professional marketer, the hypothesis was established based on preliminary research by conducting a qualitative survey of marketing experts who already experienced digital marketing in the fields as well as existing related study literature. Through a preliminary research, the degree for understanding for digital marketing, current digital marketing (including product/channel mix) execution status, and difficulties for marketers who had experienced digital marketing were figured out. Based on preliminary research, the main part of survey was designed to examine which type of product would be effective for digital marketing and which digital channel would be effective to achieve marketing performance in line with marketing objectives. To collect data, the questionnaire survey was conducted for professional marketers who had experienced digital marketing in 10 different fields including FMCG, cosmetics, distribution industry for one month (July, 10, 2014~Aug, 10, 2014). A total of 90 questionnaire were distributed and 66 questionnaires were used for the analysis, excluding the unanswered and insincere questionnaires. The data were analysed using SPSS ver.18.0. Results - The analysis for product type which is pertinent to digital marketing and prioritization for digital channel per digital marketing performance type could be summarized as followings. First, high involvement buying decision type of product and rational purchasing decision type of product in FCB grid are more effective for digital marketing in terms of marketing performance. Therefore, marketers in field would prioritize considering product type before executing digital marketing. Second, factor for sales increase, potential consumer creation and brand awareness was represented respectively 31.25%, 21.9%, and 20.8% as a result of factor analysis in terms of digital marketing channel performance. Third, effective major digital channel per digital marketing performance factor was differently identified as each digital channel has its own peculiarity. For instance, search engine is more effective for increasing sales while social media such as facebook and Kakaotalk is more effective for encouraging consumer participation. Conclusions - As a result of this study, product type and peculiarity which were pertinently fit to digital marketing were identified by using FCB grid model, and also suggested framework for decision making of digital channel selection in line with marketing objectives for effective marketing performance. It also provided insight to professional marketer which type of product could be effective for digital marketing execution as well as which factors should be measured for digital marketing performance.

• 한국의학물리학회지:의학물리
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• 제12권1호
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• pp.59-70
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• 2001

부신수질 크로마핀세포는 아세틸콜린에 반응하여 카테콜아민을 분비한다. 카테콜아민이 분비되기 위하여는 세포외 칼슘이 절대적으로 필요한데 이는 막전압 의존성 칼슘통로를 통하여 칼슘이 세포 속으로 유입되어야 분비기전이 시작됨을 시사한다. 부신수질 크로마핀 세포를 단일세포로 분리한 후 패치클람프 테크닉을 적용하여 여러 종류의 칼슘통로가 존재한다는 것이 알려져 있으나 아직 종이 달라짐에 따라 다른 칼슘통로가 존재하는 지 여부가 확실하지 않다. 그러므로 본 연구에서는 흰쥐 부신수질 크로마핀 세포를 대상으로 하여 단일 세포 패치클람프 테크닉을 적용하여 이 세포에 존재하는 다양한 칼슘통로의 존재를 확인하고자 하였다. L형 칼슘통로 억제제인 nicardipine, N형 칼슘통로 억제제인 $\omega$-CgTx GVIA, P형 칼슘통로 억제제인 $\omega$-AgaTx IVA를 사용하여 L형, N형, P형 칼슘통로가 흰쥐 부신수질 세포에 존재함을 확인하였고 개개의 칼슘통로가 전체 칼슘전류에 기여하는 정도는 L형 >N형> P형이었다.

• 약학회지
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• 제54권6호
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• pp.461-465
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• 2010

We investigated the role of L-type $Ca^{2+}$ channel in receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast formation. BayK 8644, a L-type $Ca^{2+}$ channel agonist, was shown to increase the RANKLinduced osteoclastogenesis and actin ring formation in mouse bone marrow-dereived macrophage (BMM) culture system. BayK 8644 stimulated RANKL-induced extracellular signal-regulated kinase (ERK) and p38 MAP kinase (MAPK) activation, which leads to increased nuclear factor of activated T cells (NFAT)c1 expression. Taken together, these data indicate that L-type $Ca^{2+}$ channel regulates osteoclast formation possibly through ERK- and p38-mediated NFATc1 expression.