• 한국환경과학회지
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• 제27권6호
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• pp.371-381
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• 2018

Multifunctional weirs constructed through the Four Major Rivers Restoration Project are operated as management water levels. The purpose of this study was to evaluate the effect of water level in the main stem on the tributary water level according to multifunctional weir operation, because the operation of multifunctional weirs for water level management influences the drainage of tributaries. In this study, water level pressure gauges were installed and spatial and temporal water quality was observed. The LOcally Weighted Scatterplot Smoothing (LOWESS) technique was applied to the Nakdong River and the Baekcheon Junction, both upstream of the Gangjeong-Goryeong weir, in order to analyze water quality trends. When considering the overall analysis and observations, it was found that the water quality forecasting point located at the Baekcheon estuary point should be transferred to the Dosung Bridge, which is located upstream of the Sunwon Bridge.

• 한국환경과학회지
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• 제31권6호
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• pp.491-501
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• 2022

This study evaluated the contamination levels of inland pollution sources flowing into Taeanhaean National Park. The nutritional status of influents was assessed by analyzing water quality and trophic status index (TRIX) at 52 stations, and the contamination levels of sediments were evaluated by analyzing eutrophication cleanup index (CIET) and heavy metals at 36 stations. The results of the TRIX analysis showed that 26 of the 52 stations had influents with a TRIX value of 6-10 (poor water quality/very high trophic level), indicating atrocious water quality and high eutrophication levels. The results of the CIET analysis showed that 4 out of the 36 stations were highly contaminated with organic matter. Analysis of heavy metals showed that the copper (Cu) and zinc (Zn) levels exceeded the threshold effects level (TEL) and probable effects levels (PEL) at several stations. In addition, the arsenic (As) level exceeded the threshold effects level at one station, and the levels of the other heavy metals (Cd, Cr⁶⁺, Ni, Pb, and Hg) were lower. Most inland pollution sources have been identified as small-scale, but long-term and continuous exposure can negatively affect the marine ecosystem; therefore, it necessary to prepare inland pollution source management standards and measures suitable for the characteristics of the coastal area.

• 한국동물위생학회지
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• 제46권3호
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• pp.227-234
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• 2023

It has been addressed that heat stress due to high atmospheric temperature during summer in Korea induces impaired release of reproductive hormones, followed by occurring abnormal ovarian cyclicity, lower pregnancy ratio, and reduced litter size. Therefore, the present study attempted to compare seasonal change (spring versus summer) of the ovarian aromatase expression, an enzyme for converting testosterone into estrogen. While serum estrogen level in summer group was significantly lower than that of spring group, testosterone was not different between groups. Consistent with estrogen level, the ovarian aromatase expression in summer at follicular phase was significantly lower than the counterpart of spring. The ovarian aromatase expression was positively related with serum estrogen level significantly (r=0.689; P=0.008) and strongly negative correlation was identified (r=-0.533; P=0.078) with atmospheric temperature. The ovarian aromatase expression was not detected in immature ovarian follicles but specifically localized in the granulosa cell layers in both seasons. However, the aromatase intensity in the granulosa cell layers was stronger in spring than summer. Because testosterone level was not different between groups, it could be concluded that the lower level of estrogen during summer might be derived by not lack of substrate but lower expression of ovarian aromatase by heat stress.

• 운동영양학회지
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• 제23권2호
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• pp.28-33
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• 2019

[Purpose] Recent studies have shown that glucose-6-phosphate isomerase (GPI)-which is a glycolysis interconversion enzyme-reduces oxidative stress. However, these studies are limited to tumors such as fibrosarcoma, and there are no studies that have examined the effects of exercise on GPI expression in mice skeletal muscle. Furthermore, GPI acts in an autocrine manner thorough its receptor, autocrine motility factor receptor (AMFR); therefore, we investigated expression level changes of secreted GPI from skeletal muscle in in vitro study to examine the potential role of GPI on skeletal muscle. [Methods] First, we performed an in vitro study, to identify the condition that upregulates GPI levels in skeletal muscle cells; we treated C2C12 muscle cells with an exercise-mimicking chemical, AICAR. AICAR treatment upregulated GPI expression level in C2C12 cell and its secretomes. To confirm the direct effect of GPI on skeletal muscle cells, we treated C2C12 cells with GPI recombinant protein. [Results] We found that GPI improved the viability of C2C12 cells. In the in vivo study, the exercise-treated mice group showed upregulated GPI expression in skeletal muscle. Based on the in vitro study results, we speculated that expression level of GPI in skeletal muscle might be associated with muscle function. We analyzed the association between GPI expression level and the grip strength of the all mice group. The mice group's grip strengths were upregulated after 2 weeks of treadmill exercise, and GPI expression level positively correlated with the grip strength. [Conclusion] These results suggested that the exercise-induced GPI expression in skeletal muscle might have a positive effect on skeletal muscle function.

• 대기
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• 제23권2호
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• pp.187-204
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• 2013

This study analyzed the synoptic distribution and vertical structure about four cases of precipitation occurrences using NCEP/NCAR reanalysis data and upper level data of winter intensive observation to be performed by National Institute of Meteorological Research at Bukgangneung, Incheon, Boseong during 63days from 4 JAN to 6 MAR in 2012, and Observing System Experiment (OSE) using 3DVAR-WRF system was conducted to examine the precipitation predictability of upper level data at western and southern coastal regions. The synoptic characteristics of selected precipitation occurrences were investigated as causes for 1) rainfall events with effect of moisture convergence owing to low pressure passing through south sea on 19 JAN, 2) snowfall events due to moisture inflowing from yellow sea with propagation of Siberian high pressure after low pressure passage over middle northern region on 31 JAN, 3) rainfall event with effect of weak pressure trough in west low and east high pressure system on 25 FEB, 4) rainfall event due to moisture inflow according to low pressures over Bohai bay and south eastern sea on 5 MAR. However, it is identified that vertical structure of atmosphere had different characteristics with heavy rainfall system in summer. Firstly, depth of convection was narrow due to absence of moisture convergence and strong ascending air current in middle layer. Secondly, warm air advection by veering wind with height only existed in low layer. Thirdly, unstable layer was limited in the narrow depth due to low surface temperature although it formed, and also values of instability indices were not high. Fourthly, total water vapor amounts containing into atmosphere was small due to low temperature distribution so that precipitable water vapor could be little amounts. As result of OSE conducting with upper level data of Incheon and Boseong station, 12 hours accumulated precipitation distributions of control experiment and experiments with additional upper level data were similar with ones of observation data at 610 stations. Although Equitable Threat Scores (ETS) were different according to cases and thresholds, it was verified positive influence of upper level data for precipitation predictability as resulting with high improvement rates of 33.3% in experiment with upper level data of Incheon (INC_EXP), 85.7% in experiment with upper level data of Boseong (BOS_EXP), and 142.9% in experiment with upper level data of both Incheon and Boseong (INC_BOS_EXP) about accumulated precipitation more than 5 mm / 12 hours on 31 January 2012.

• 대한한의학방제학회지
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• 제18권1호
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• pp.181-189
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• 2010

Objectives : In order to confirm a remedial effect and related influence of the clinic treatment by prescribing Samchuljojung-tang(蔘朮調中湯), Bojungikqi-tang(補中益氣湯) and Samso-um(蔘蘇飮) to patients who suffering from a chronic cough and rhinorrhea. Methods : 1. In a clinical observation and analysis method, we have selected the 23 patients who have visited National Oriental Medical Center, date from 2007.8.21 to 2008.7.31 and suffering from a chronic cough and rhinorrhea caused by the common cold sequelae. 2. Separated them into three types(I: cough type, II: rhinorrhea type, III: cough & rhinorrhea type). 3. Observed thoroughly the level of symptom and recorded it for each type with questionnaire survey at the beginning set 4. Prescribed Samchuljojung-tang, Bojungikqi-tang and Samso-um for type I, II, III respectively. 5. Observed the level of symptom and treatment afterwards affect, and recorded movements of intensity level for 3 types with same questionnaires. Results : 1. Type I : The survey turned out to be from 9 patients, initial level recorded 31.89 at the entry diagnosis, and next level that means changing of symptoms, recorded to 12.67 after prescribing herb medication. 2. Type II : From 11 patients, initial level was 32.82 and next level was 13.45. 3. Type III : From 3 patients, initial level was 37.67 and next one was 16.00. Conclusions : It is concluded that there is a significant remedial effect and related influence of the clinic treatment for each type of patients who suffering from a chronic cough and rhinorrhea caused by the common cold sequelae.

• 대한환경공학회지
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• 제27권10호
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• pp.1090-1098
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• 2005

벤조일 퍼록사이드는 수서생물에 대해 매우 높은 독성을 나타냄에도 불구하고 환경 중 잔류 농도 및 노출영향에 대해 연구가 이루어지지 않아 OECD에서 추천하고 있는 대표적인 다매체 환경거동 모델인 EQC 모델을 이용하여 본 물질에 대한 환경중의 농도를 예측하고 위해성평가 및 화학물질의 관리를 수행하기 위한 기초자료로 활용코자 하였다. 평형, 정상상태에서 100,000 kg의 벤조일 퍼록사이드가 환경내로 유입된 상태를 나타내는 Level I과 평형, 정상상태 이류와 분해현상이 있고 일정한 속도 1,000 kg/h로 유입되었을 경우를 나타내는 Level II에서 벤조일 퍼록사이드는 주로 토양(68.3%)과 물(28.7%)로 배출되는 것으로 예측되었다. 비평형, 정상상태, 이류와 분해현상이 있고 다매체 이동을 하는 시스템에서 벤조일 퍼록사이드가 대기, 물, 토양, 침전물의 각각의 4개 매체에 연속적으로 1,000 kg/h로 유입될 경우인 Level III에서는 주로 토양(99.9%)으로 배출되었고 전체 잔류시간은 3.4년으로 예측되어 벤조일 퍼록사이드가 환경 중에 잔류성이 있는 물질로 평가되었다.

• 벤처창업연구
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• 제15권6호
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• pp.55-65
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• 2020

본 연구는 국가 경제 성장과 관련된 창업 (start-up) 활동에 영향을 미치는 요인을 분석하는 국가 수준에서의 실증 연구이다. 창업 활동의 기반인 기업가정신에 대한 개인 수준에서 분석과 달리 GEM (Global Entrepreneur Monitor)에서 발행한 연간 데이터베이스를 활용한 실증 분석을 수행하였다. 나라별 초기창업활동 (TEA: total early-stage entrepreneurial activity) 지수를 이용하여 TEA에 영향을 미치는 영향요인을 경제 요인과 비경제적 요인을 구분하여 분석하였다. 선행 연구를 기반으로 국민소득 수준, 실업률을 포함하여 국가의 문화적 특성 변수 등 9개 요인을 국가 창업 활동의 영향 요인으로 제시하였으며 경제발전 수준에 따라 요소주도형, 효율주도형, 혁신주도형으로 국가를 구분한 패널데이터를 회귀 분석 모형을 통하여 실증 분석하였다. 본 연구의 분석 결과, 기존연구들에서 설명하고 있는 국민소득 수준과 창업 활동 사이의 U자 형태'를 명시적인 2차 함수 회귀분석을 통하여 추정하였으며 그에 따라 창업활동의 변곡점이 되는 소득수준을 발견하였다. 이러한 결과를 통해서 요소주도형 및 효율성주도형 경제에서는 생계형 창업활동이 활발한 반면 혁신주도형 경제에서는 기회추구형 창업활동이 활발하다는 기존의 주장들을 설명할 수 있음을 보였다. 특히, 창업활동 활성화를 위한 정부지원 프로그램에 대해 실증분석해 본 결과, 요소주도형 및 효율성주도형 경제에서는 유의한 긍정적 효과를 미치고 있으나 혁신형 경제에서는 그 효과가 오히려 부정적이라는 결과를 발견하였다. 이는 창업지원 정책이 경제발전단계에 따라 달라져야 함을 보여주는 결과로서 많은 정책적 시사점을 제시한다. 마지막으로 창업관련 교육의 정도와 새로운 비즈니스를 지원하는 사회문화적인 규범으로서의 창업 문화는 국가의 경제 수준과 상관없이 모두 창업활동에 긍정적인 영향을 미치고 있음을 발견하였다. 이는 어느 단계의 경제이든 창업 문화 조성이 필요하다는 시사점을 함축하고 있다.

• 대한응급의학회지
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• 제29권5호
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• pp.430-436
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• 2018

Objective: The purpose of this study was to evaluate whether or not the d-dimer level indicating hyperfibrinolysis could be a predictor of early poor outcome (massive transfusion, death within 24 hours) associated with trauma-induced coagulopathy in blunt trauma without significant brain injury. Methods: This study was a retrospective observational study using 516 blunt trauma patients without significant brain injury. The poor outcome group, including patients receiving massive transfusion and those who died within 24 hours, consisted of 33 patients (6.4%). The variables were compared between the poor outcome group and good outcome group, and logistic regression analysis was performed using statistically significant variables. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the poor outcome prediction ability of the initial d-dimer level. Results: The poor outcome group showed more serious anatomical, physiological, and laboratory data than the good outcome group. In the ROC curve analysis for evaluation of the poor outcome prediction of the d-dimer level, the area under the curve value was 0.87 (95% confidence interval [CI], 0.84-0.90) while the cut-off value was 27.35 mg/L. In the logistic regression analysis, the high d-dimer level was shown to be an independent predictor of poor outcome (adjusted odds ratio, 14.87; 95% CI, 2.96-74.67). Conclusion: The high d-dimer level (>27.35 mg/L) can be used as a predictor for the poor outcome of patients with blunt trauma without significant brain injury.

• The Journal of Advanced Prosthodontics
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• 제12권5호
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• pp.316-321
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• 2020

PURPOSE. The stress distribution and microgap formation on an implant abutment structure was evaluated to determine the relationship between the direction of the load and the stress value. MATERIALS AND METHODS. Two types of three-dimensional models for the mandibular first molar were designed: bone-level implant and tissue-level implant. Each group consisted of an implant, surrounding bone, abutment, screw, and crown. Static finite element analysis was simulated through 200 N of occlusal load and preload at five different load directions: 0, 15, 30, 45, and 60°. The von Mises stress of the abutment and implant was evaluated. Microgap formation on the implant-abutment interface was also analyzed. RESULTS. The stress values in the implant were as follows: 525, 322, 561, 778, and 1150 MPa in a bone level implant, and 254, 182, 259, 364, and 436 MPa in a tissue level implant at a load direction of 0, 15, 30, 45, and 60°, respectively. For microgap formation between the implant and abutment interface, three to seven-micron gaps were observed in the bone level implant under a load at 45 and 60°. In contrast, a three-micron gap was observed in the tissue level implant under a load at only 60°. CONCLUSION. The mean stress of bone-level implant showed 2.2 times higher than that of tissue-level implant. When considering the loading point of occlusal surface and the direction of load, higher stress was noted when the vector was from the center of rotation in the implant prostheses.