• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.267-268
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• 2000

Burnstone등이 어류장의 미주신경지배에 대해서 연구한 이래로 Burka et al는 무지개송어 위장관에서 Carbachol과 5-HT가 농도의존적으로 수축함을 밝혔다. 그리고 무지개송어의 위장관수축반응은 무스카린성 M2 subtype 수용체를 경유한다고 하였으며, Ach-유발된 수축이 nicotine이나 hexamethonium을 고농도로 처치시에 억제되었고, 이는 ACh의 반응이 preganglionic cholinergic fiber에 의존함을 암시하였다. 이전의 경골어류장의 여러 수용체에 대한 연구는 주로 송어류에서 이루어져 왔으며, 타 어종에서의 연구는 별로 없었다. (중략)

• Journal of Yeungnam Medical Science
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• v.5 no.2
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• pp.1-8
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• 1988

위장관에서 분비되는 많은 국소호르몬 중에서 이미 널리 알려진 것을 외에 구조적인 공통점을 가진 새로운 group인 pancreatic polypeptide family에 대한 정보를 요약하여 보았다. PP, NPY 및 PYY는 그 구조적 유사점들에도 불구하고 분비되는 장소가 판이하여, PP는 위와 췌장의 국소호르몬으로서, NPY는 중추 및 말초신경의 신경충동전달체로서, 또 PYY는 하부위장관 점막에서부터 분비되어 전신 호르몬처럼 작용하고 있다. 이들 NPY와 PYY의 혈관수축작용과 혈압상승작용은 우리의 흥미를 끌기에 충분하다. 특히 PYY는 주로 하부장관 특히 결장과 직장의 분비조직에서 많이 발견된다는 점과 돼지의 뇌혈관을 수축시켰다는 점이 주목할 만한 것이다. 우리나라에는 많은 고혈압 환자가 있으며, 고혈압을 비롯한 여러가지 원인에 의한 뇌졸중(뇌출혈 포함) 환자도 많이 발생하고 있다. 민간의 속설에 의하면 출혈성 뇌졸증이 기온이 낮은 계절에 보다 자주 발생하는 경향이 있으며, 이른아침 화장실에서의 배변시 자주 발생한다고 한다. 물론 이러한 속설을 뒷받침할 만한 자료가 없으므로 학문적 견지에서의 신빙성 여부를 논할 가치는 없겠으나, 배변시 비교적 강한 자극을 받고 활발한 운동을 하는 결장과 직장에 PYY의 분비세포가 집결되어 있다는 점과 PYY의 뇌혈관수축작용 및 혈압 상승작용 등을 고려해 볼 때, 출혈성 뇌졸증과 PYY의 상관관계는 추구해볼 만한 사항이라 사료된다.

• Journal of Convergence for Information Technology
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• v.10 no.10
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• pp.109-114
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• 2020

The aim of the study was to observe the influence and related mechanism of rebamipide on the intestinal contraction. Intestinal contraction includes the activation of thick or thin filament regulation. However, there are few reports addressing the question whether this regulation is involved in rebamipide-induced regulation. We hypothesized that rebamipide plays a role in intestinal contraction evoked by carbachol in rat intestine. Interestingly, rebamipide alone didn't inhibit and rather slightly increased the contraction in the denuded muscle. Therefore, rebamipide alone and together with indomethacin increases the ileal contraction suggesting that additional pathways might be involved in the regulation of ileal contractility. In conclusion, rebamipide has some effect on the regulation of contractility and anti-ulcer by NSAIDs.

• Journal of the Korea Concrete Institute
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• v.20 no.2
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• pp.131-138
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• 2008

Humidity and strain were estimated for understanding the relation between humidity change by self-desiccation and shrinkage in high-performance concrete with low water binder ratio. Internal humidity change and shrinkage strain were about 10%, 4% and $320\times10^{-6}$, $120\times10^{-6}$ respectively on concrete with water binder ratio 0.3, 0.4 and from the results, humidity change and shrinkage represented the strong linear relation regardless of mixture. For specifying the relation on internal humidity change and autogenous shrinkage strain, shrinkage model was established which is driven by capillary pressure in pore water and surface energy in hydrates on the assumption of a single network and extended meniscus in pore system of concrete. This model and experimental results had a similar tendency so it would be concluded that the internal humidity change by self-desiccation in HPC originated in small pores less than 20 nm, therefore controlling plan on autogenous shrinkage might be focused on surface tension of water and degree of saturation in small pore.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.592-602
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• 2020

This study examined the contribution of the risk factors that cause cardiovascular disease in Koreans. The subjects were 20,012 adults aged 30~74 years who were enrolled from the 2005~2013 Korean National Health and Nutrition Examination Survey, had filled the risk factors data, and had no cardiovascular disease history. Data analysis was conducted using SAS 9.3, and a weighted composite sample design analysis was performed. The contribution was obtained by applying a squared semi-partial correlation. As a result, they were higher in the order of age (63.9%), smoking (17.3%), systolic blood pressure (7.9%), diabetes (6.9%), antihypertensive medication use (3.0%), and BMI (0.9%) in men. In women, the contributions were in the order of age (54.1%), systolic blood pressure (23.5%), diabetes (13.6%), antihypertensive medication use (5.1%), smoking (3.1%), and BMI (0.6%%). According to age bracket analysis, smoking (51.8~33.7%) was the biggest risk factor, followed in order by age (26.6%) in their 30s and systolic blood pressure (17.3~21.0%) in those older than 40 years in men. In women, the systolic blood pressure (56.2~40.5%) was the main contributor to the risk factors, followed by age (24.0%) in their 30s and diabetes (13.6~32.6%) in those older than 40 years. The contribution of the income level was similar. Therefore, to prevent cardiovascular disease, various programs that reflect the contributions of the risk factors should be developed. Moreover, it is recommended to use the results shown in this study as basic data.

• Journal of Convergence for Information Technology
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• v.11 no.10
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• pp.131-137
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• 2021

The aim of the study was to observe the influence and related mechanism of histamine and its analogues used for hypersensitivity tests and used as an indicator of impurities in drugs on the tissue-specific intestinal contraction. Intestinal contraction includes the activation of thick or thin filament regulation. However, there are few reports addressing the question whether this regulation is involved in histamine-induced regulation. We hypothesized that histamine plays a role in tissue-dependent regulation of intestinal contractility. Denuded ileal/colonic longitudinal and circular muscles of male rats were used and isometric contractions were recorded using a data acquisition system. Interestingly, histamine alone didn't increase the contraction of the circular muscle but increased the contraction of the longitudinal muscle. Histamine together with atropine (M3 receptor antagonist) didn't inhibit the contraction of the longitudinal and circular muscle. Therefore, histamine alone and together with atropine increases the ileal longitudinal muscle contraction suggesting that additional mechanisms (decreased receptor density, postreceptor signaling or distribution of agonists) might be involved in the regulation of ileal muscle contractility. In conclusion, histamine and/or atropine has some effect on the regulation of the longitudinal contractility regardless of M3 receptor and the simpler test would be preferred as the drug impurity test compared to more complicated tests.

• Journal of the Korean GEO-environmental Society
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• v.3 no.2
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• pp.5-14
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• 2002

In this study, stress-deformation characteristics of buried pipe are studied. A numerical model, i.e., Egg-Cam Clay is introduced for the analysis of soft clay. Cam Clay model has a difficulty in analyzing soft clay that has two properties of shrinkage and swelling. Egg-Cam Clay model is modified format of Cam Clay model. In addition, Mohr-Coulomb model using finite element method is employed to verify effects of the geogrid, EPS geofoam. Stress deformation of several cases of pipe and other reinforcemnt material combinations are analyzed. Geofoam and geogrid have positive effects on the deformation characteristics.

• Journal of the Korea Concrete Institute
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• v.18 no.2 s.92
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• pp.213-218
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• 2006

Meniscus, adsorbed layer thickness, capillary pressure and disjoining pressure was deduced in extended meniscus region in cement paste pore by hydrostatic equilibrium. From the results, the relationship between pore size and adsorbed layer thickness could be derived and adsorbed layer thickness represents $0.299{\sim}2.700nm$ according to pore size $1nm{\sim}1{\mu}m$. Especially, disjoining pressure rapidly Increased in less than 10 nm pore size according to adsorbed layer thickness. Therefore, it is interpreted that autogenous shrinkage of cement paste is highly increases in formation of less than 10 nm pore size. Predictions of autogenous shrinkage in cement paste considering driving force for autogenous shrinkage with capillary pressure and disjoining pressure was low in comparison with experiment values between $1{\sim}4$ days and high in later period. These tendency could be thought that pore damage by mercury injection in early age makes shrinkage driving force underestimate and assumption for unsaturated independent pore makes overestimate. These interactions might be needed corrections considering on hydration or pore replacement model.

• Proceedings of the KWS Conference
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• 1994.05a
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• pp.241-242
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• 1994

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4A
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• pp.353-359
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• 2010

Cementitious matrix based composites are vulnerable to the drying shrinkage crack during the curing process. In this study, the drying shrinkage induced fracture behavior of the fiber reinforced concrete is simulated and the effects of the fiber reinforcement conditions on the fracture characteristics are analysed. The numerical model is composed of conduit elements and rigid-body-spring elements on the identical irregular lattice topology, where the drying shrinkage is presented by the coupling of nonmechanical-mechanical behaviors handled by those respective element types. Semi-discrete fiber elements are applied within the rigid-body-spring network to model the fiber reinforcement. The shrinkage parameters are calibrated through the KS F 2424 free drying shrinkage test simulation and comparison of the time-shrinkage strain curves. Next, the KS F 2595 restrained drying shrinkage test is simulated for various fiber volume fractions and the numerical model is verified by comparison of the crack initiating time with the previous experimental results. In addition, the drying shrinkage cracking phenomenon is analysed with change in the length and the surface shape of the fibers, the measurement of the maximum crack width in the numerical experiment indicates the judgement of the crack controlling effect.