• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제1권2호
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• pp.105-117
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• 1997

The formation mechanism of the vortex streets in the lee of the mountain is investigated by a three-dimensional numerical model. The model is based upon the hydrostatic Boussinesq equations in which the vertical turbulent momentum flux is estimated by a turbulence parameterization scheme, but the horizontal viscosity is assumed to be constant. The results show that Karman vortex streets can form even without surface friction in a constant ambient flow with uniform stratification. The vortex formation is related to breaking of the mountain wave, which depends on the Froude number (Fr). In the case of a three-dimensional bell-shaped mountain, the wave breaking occurs when Fr is less than about 0.8, while a Karman vortex forms when Fr is less than about 0.22. Vortex formation also depends on Reynolds number, which is estimated from the horizontal diffusivity. The vortex formation can be explained by the wave saturation theory given by Lindzen (1981) with some modification. Simulations in this study show that in the case of Karman vortex formation the momentum flux in the lower level is much larger than the saturated momentum flux whereas it is almost equal to the saturated momentum at the upper levels as expected from the saturation theory. As a result, large flux divergence is produced in the lower layer, the mean flow is decelerated behind the mountain, and the horizontal wind shear forms between unmodified ambient wind. The momentum exchange between the mean flow and the mountain wave is produced by the turbulence within a breaking wave. From the result, well developed vortices like Karman vortex can be formed. The results of the momentum budget calculated by the hydrostatic model are almost the same as nonhydrostatic results as long as horizontal scale of the mountain is 10 km. A well developed Karman vortex similar to the hydrostatic one was simulated in the nonhydrostatic case. Therefore, we conclude that the hydrostatic assumption is adequate to investigate the origin of the Karman vortex from the viewpoint of wave breaking.

• Asian-Australasian Journal of Animal Sciences
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• 제14권4호
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• pp.507-514
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• 2001

Two experiments were carried out to investigate whether duckweed is useful as a dietary protein source for fine-wool Merino sheep and to evaluate its effects on wool yield and characteristics. In Experiment 1, the sheep were given one of three maintenance diets consisting of oaten chaff (520-700 g/d) supplemented with 16-32 g crude protein/d in the form of fresh (1 kg/d) or sun-dried (50-100 g/d) duckweed. Each ration was estimated to provide 5.4 MJ (1.3 Mcal)/d of metabolisable energy (ME). The sheep readily ingested the fresh or dried duckweed. None of the wool measures (yield, rate of fibre elongation, fibre diameter) differed (p>0.05) between dietary treatments. In Experiment 2, oaten-chaff-based diets (800 g/d) supplying 6.5-7.2 MJ (1.6-1.7 Mcal)/d of ME were supplemented with iso-nitrogenous amounts (4-5 g N) either of urea (8 g), cottonseed meal (60 g) or dried duckweed (100 g). In this experiment, the rate of wool fibre elongation, thought to be related to intestinal amino acid absorption, was lower (p<0.05) for sheep given the oaten chaff/urea diet than for those given either oaten chaff/cottonseed meal or oaten chaff/duckweed for which the rates did not differ (p>0.05). Fibre diameter, which ranged from 16.0-16.7 mm, did not differ (p>0.05) between diets, but tended to be lower on the oaten chaff/urea diet so that volume of wool produced was also significantly lower (p<0.05) on this diet than on the diets containing duckweed or cottonseed meal. Rumen ammonia concentrations at 4.5 and 7.5 h after feeding were higher (p<0.05) for sheep given the oaten chaff/urea diet than for those given the other two diets. A comparison of the rumen ammonia concentrations, wool growth rate and predicted flows of amino acids from the rumen of sheep supplemented with duckweed rather than cottonseed meal suggested that duckweed is a valuable source of 'escape protein' for ruminants.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4835-4838
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• 2013

Background: We compared treatment completion rates and safety of docetaxel and cyclophosphamide sixcycle therapy (TC6) with docetaxel followed by 5FU, epirubicin and cyclophosphamide (T-FEC) therapy in Japanese patients with human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Materials and Methods: We administered TC6 q3w or T-FEC q3w to HER2-negative breast cancer patients. The primary endpoint of this trial was toxicity. As second endpoints, the treatment completion rate and relative dose intensity were evaluated. Results: The TC6 and T-FEC group consisted of 22 and 21 patients, respectively. Concerning hematological toxicity, grade 3 or higher adverse reactions included neutropenia and febrile neutropenia. As non-hematological adverse events, exanthema and peripheral neuropathy were frequently reported in the TC6 group, whereas more patients of the T-FEC group reported nausea and vomiting. In TC6, the treatment completion rate was 86.4% and the relative dose intensity of docetaxel was 93.2%. In T-FEC, the values were 95.2% and 98.9%, respectively. Conclusions: These results suggest that TC6 is tolerable in Japanese, and that this regimen can also be performed in outpatient clinics. However, with the TC6 regimen, the compliance was slightly lower than with the T-FEC regimen, and supportive therapy needs to be managed appropriately.

• 한국콘텐츠학회논문지
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• 제16권4호
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• pp.262-274
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• 2016

인디뮤지션에 대한 사회적 의미와 관심이 높아지고 있음에도 불구하고, 인디뮤지션을 학술적인 차원에서 이해하기 위한 시도와 이들을 위한 제도적 평가는 미흡했다. 본 연구에서는 105명의 국내 인디뮤지션에 대한 온라인 설문 조사를 통해 이들의 음악 환경, 음악 활동의 특성, 인디뮤지션 만족도에 영향을 미치는 요인들을 살펴보고자 하였다. 분석 결과, 대부분의 응답자들은 작업 시설과 50석 이상의 공연장 이용 기회가 부족하다고 평가한 것으로 나타났다. 또한 활동 경력이 6년 이상인 집단의 경우, 대형 공연장 공연 기회가 많으며, 음악 활동 횟수와 음악 활동 수입이 상대적으로 높은 것으로 나타났다. 인디뮤지션의 만족도에는 음악활동 횟수, 사회적인 인정이 영향을 미치는 것으로 나타났다. 인디뮤지션에 대한 지원제도는 다양한 영역에서 제공되는 지원이 서로 조화를 이루는 토대를 마련하는데 집중해야할 것이며, 정부가 모든 것을 해야 한다는 가부장적 사고를 버리고 다양한 부문과의 조율을 통해 인디뮤지션의 창작을 독려해야할 것이다.

• 한국콘텐츠학회논문지
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• 제13권11호
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• pp.636-643
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• 2013

방송시장의 급격한 환경변화는 지역방송의 사회적 입지를 위축시키고 재정적 기반을 위협하고 있지만, 동시에 인터넷과 모바일 기반의 플랫폼과 스마트 미디어는 새로운 콘텐츠 유통의 활로로서 가능성을 부여하고 있다. 본 연구는 지역 지상파방송의 수퍼스테이션 사례 및 전문가 인터뷰를 통해 변화하는 방송환경에 적합한 지역방송의 유통모델을 살펴보고, 새로운 유통모델 확립을 위해 지역방송의 역할과 추진해야 할 전략을 논의하였다. MBCNET의 재무성과 및 시청률, 뉴미디어 유통에 대한 분석결과, MBCNET은 콘텐츠 라이브러리와 MBC 지역방송사의 영향력에 힘입어 성공적인 성과를 내고 있는 것으로 나타났다. 그러나 지속적인 경쟁력 강화를 위해 콘텐츠와 플랫폼의 마케팅역량의 향상이 필요하며, 시청자들의 이용행태에 기반한 경쟁력 있는 콘텐츠의 제작역량 강화 및 N스크린 환경에 대응할 수 있는 조직의 정비가 필요한 것으로 분석되었다.

• 한국콘텐츠학회논문지
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• 제13권11호
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• pp.1-10
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• 2013

방송통신융합을 통해 양방향 기능이 방송에서 차지하는 비중이 점차 확장되고 있지만, 위성방송의 경우 양방향 기능이 IPTV나 케이블TV에 비해 뒤쳐져 이에 대한 전략적 서비스로 PVR이 도입되었다. 본 연구는 위성방송가입자들의 PVR 이용행태분석을 통해 현재 도입되고 있는 클라우드 PVR의 주력 서비스 방향에 실증적 정보를 제공하고자 하였다. 위성방송가입자들의 PVR 이용분석 결과, 주된 PVR 이용기능은 '시간대 이동(time-shifting)'으로 나타났으며, PVR의 이용이 많은 이용자일수록 TV 시청량이 증가하는 것으로 분석되었다. 또한 PVR이 방송프로그램을 시청하는데 있어 장르의 집중(concentration)보다는 다양화(diversification)를 가져오는 것으로 나타났다. 결과적으로 PVR의 활성화는 온에어 방송의 시청시간을 자유롭게 변경함으로써 TV이용의 증가 및 다양한 장르의 시청유도에 긍정적 영향을 미치는 것으로 분석되었다.

• Journal of Korean Neurosurgical Society
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• 제59권5호
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• pp.466-470
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• 2016

Objective : To determine imaging features that may separate adamantinomatous and papillary variants of craniopharyngiomas given that tumors with adamantinomatous signature features are associated with higher recurrence rates, morbidity, and mortality. We specifically reviewed calcification on CT, T1 bright signal intensity, and cystic change on T2 weighted images for differentiating these two types. Methods : We retrospectively reviewed the MRI and CT studies in 38 consecutive patients with pathologically proven craniopharyngiomas between January 2004 and February 2014 for the presence of calcification on CT scans, bright signal intensity on T1 weighted images, and cystic change on T2 weighted images. Results : Of the 38 craniopharyngiomas, 30 were adamantinomatous type and 8 were papillary type. On CT scans, calcification was present in 25 of 38 tumors. All calcified tumors were adamantinomatous type. Twenty four of 38 tumors had bright signal intensity on T1 weighted images. Of these 24 tumors, 22 (91.7%) were adamantinomatous and 2 were papillary type. Cystic change on T2 weighted images was noted in 37 of 38 tumors; only 1 tumor with papillary type did not show cystic change. Conclusion : T1 bright signal intensity and calcification on CT scans uniformly favor the adamantinomatous type over papillary type of craniopharyngioma in children. However, these findings are more variable in adults where calcification and T1 bright signal intensity occur in 70.6% and 58.8% respectively of adult adamantinomatous types of craniopharyngiomas.

• Journal of Periodontal and Implant Science
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• 제27권4호
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• pp.805-818
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• 1997

Immune responses of periodontal tissue may be regulated by products of sensory afferent nerve endings such as neuropeptides. Substance P(SP), a tachykinin neuropeptide, has been previously reported to stimulate the activities of T lymphocyte. Therefore, I examined the role of SP in IL-2 production and cell proliferation by using a homogeneous line of T lymphocytes(Jurkat and HuT78). Cell proliferation rate was determined by [$^3H$]-thymidine incorporation test, and IL-2 was quantitated by the growth rate of CD4+ IL-2-dependent T lymphocyte line CTLL-2. SP stimulated cell proliferation of T lymphocytes at the concentration of $10^{-12}$ and $10^{-8}$M in a biphasic bell-shape dose-dependent manner. However, SP alone did not induce IL-2 release at the concentration range of $10^{-6}$ to $10^{-14}$M. The upregulation of IL-2 release was observed when $10^{-12}$M SP was applied together with mitogens such as Con A or PHA+PMA on T cell lines, especially on Jurkat. Con A or PHA+PMA demonstrated to increase the rate of cell proliferation of Jurkat, which had shown to produce much amount of IL-2 indicating that mitogen-induced cell proliferation might be partially influenced by released IL-2. It was concluded that regulatory effects of SP on the immune/inflammatory response could be mediated through the costimulatory upregulation of IL-2 production and increase of cell proliferation of T lymphocyte.

• Clinical and Experimental Pediatrics
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• 제48권2호
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• pp.174-177
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• 2005

목 적 : HSP로 진단된 환아들에서 역학, 임상양상 및 경과를 알아보고자 하였다. 방 법 : 1987년 1월부터 2003년 12월까지 가톨릭대학교 대전 성모병원에 입원하여 HSP로 진단받은 424명의 환아를 대상으로 환아의 의무기록을 통해 임상 양상 및 역학적 지표들을 조사 분석하였다. 결 과 : 연간 평균 발생 수는 $25.1{\pm}7.9$명이었고, 연도별 발생은 일정한 주기를 보이지 않았다. 일년을 통해 지속적인 발생이 있었으나 하절기에 발생이 적었다. 남녀비는 1.3 : 1이었고, 평균 연령은 6.6세이었다. 연령분포는 4-6세를 정점으로 종형의 분포를 보였고 92.7%의 환아가 2-11세 사이에 발생하였다. 임상 증상으로 자반은 100%, 위장 증상이 53.8%, 관절 증상 40.8%, 신장 증상이 18.9%에서 나타났으며, 신증후군은 1%의 환아에서 관찰되었다. 결 론 : 이번 연구에서의 HSP의 임상 및 역학적 특성은 시대적인 변화 없이 미국을 비롯한 외국과 국내의 이전 보고들과 거의 유사하였다.

• Molecules and Cells
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• 제39권2호
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• pp.149-155
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• 2016

In the heart, excitation-contraction (E-C) coupling is mediated by $Ca^{2+}$ release from sarcoplasmic reticulum (SR) through the interactions of proteins forming the $Ca^{2+}$ release unit (CRU). Among them, calsequestrin (CSQ) and histidine-rich $Ca^{2+}$ binding protein (HRC) are known to bind the charged luminal region of triadin (TRN) and thus directly or indirectly regulate ryanodine receptor 2 (RyR2) activity. However, the mechanisms of CSQ and HRC mediated regulation of RyR2 activity through TRN have remained unclear. We first examined the minimal KEKE motif of TRN involved in the interactions with CSQ2, HRC and RyR2 using TRN deletion mutants and in vitro binding assays. The results showed that CSQ2, HRC and RyR2 share the same KEKE motif region on the distal part of TRN (aa 202-231). Second, in vitro binding assays were conducted to examine the $Ca^{2+}$ dependence of protein-protein interactions (PPI). The results showed that TRN-HRC interaction had a bell-shaped $Ca^{2+}$ dependence, which peaked at pCa4, whereas TRN-CSQ2 or TRN-RyR2 interaction did not show such $Ca^{2+}$ dependence pattern. Third, competitive binding was conducted to examine whether CSQ2, HRC, or RyR2 affects the TRN-HRC or TRN-CSQ2 binding at pCa4. Among them, only CSQ2 or RyR2 competitively inhibited TRN-HRC binding, suggesting that HRC can confer functional refractoriness to CRU, which could be beneficial for reloading of $Ca^{2+}$ into SR at intermediate $Ca^{2+}$ concentrations.