본 연구는 국립산림치유원에서 교사를 대상으로 실시한 1박 2일형 ‘행복학교 에듀힐링 캠프’에 참가한 교사 221명을 대상으로 하였다. 산림치유프로그램이 교사들의 스트레스 해소와 긍정･부정감정에 어떻게 영향을 미치는지 알아보기 위하여 본 연구를 실시하였다. 자료분석은 SPSS 24.0 프로그램을 사용하여 대응표본 t-검정을 실시하였다. 산림치유프 로그램 참가 전과 후의 스트레스 반응 지수, 긍정･부정감정의 차이를 살펴본 결과, 그 차이가 확인되었다. 연구결과 산림치유프로그램에 참가한 교사들의 스트레스반응 지수와 하위 영역인 신체 증상, 우울 증상, 분노 증상이 유의하게 낮아졌으며, 교사 직책별(비담임교사, 담임교사, 부장교사, 교장, 교감) 스트레스 감소효과에서도 모든 그룹에서 유의한 결과를 보였다. 숲에서의 산림치유프로그램이 교사들의 스트레스 저감과 부정감정 해소에 효과적임을 보여주고 있다. 스트레스 위험에 노출된 교사들을 위하여 적극적인 산림치유 활동이 활성화되기를 기대한다.

Halitosis is a bad odor in mouth. The etiology of halitosis is multifactorial including intra-oral and extra-oral causes. It affects social interactions in many people. The aim of this study is to investigate an association between recognition group and non-recognition group by evaluating halitosis level and systemic factors. Nineteen participants who visited Department of Periodontology of Seoul National University Bundang Hospital were enrolled. Volatile sulfur a compounds (VSCs) were measured by Oral ChromaⓇ, a questionnaire was requested and oral exam was carried out in all subjects. Female is more sensitive than male for oral malodor. VSCs level of hydrogen sulfide(H2S) and methyl mercaptan(CH3SH) in male is higher than that in female. Participants who gave appeal dry mouth seem to recognize halitosis.

This study analyzed characteristics of ozone (O3) formation regimes in Busan over a period of recent five years (2015~2019) and compared the findings with those obtained in Seoul. We employed four observed variations: early morning commuting-hour (i.e., 06:00-09:00 LST) nitrogen dioxide (NO2), peak-hour (i.e., 12:00-16:00 LST) O3, 8-hour average O3 (MDA8 O3), and △O3 (=O3_max- O3_min) in Busan and Seoul. In addition, the NO2-O3 relation was assessed to interpret which of NOx-limited or volatile organic compound (VOC)-limited was dominant. In Busan, the annual mean O3 concentration was relatively higher than in Seoul, whereas there were fewer high-concentration days. The Pearson correlation coefficients (R) between Early morning-hour NO2 and the Peak-hour O3 was positive (but close to zero) in Busan and negative in Seoul. Likewise, the R between the Early morning-hour NO2 and the △O3 showed a relatively considerable positive correlation (R=+0.4~0.5) in Busan, while a weak positive correlation (R=+0.1~0.2) in Seoul. From this result, it can be inferred that the O3 formation regime in Busan was intrepreted to be nearly neutral or relatively closer to the NOx-limited regime than Seoul, while Seoul to the VOC-limited regime. The study findings imply that O3 control strategies should be applied differently in Busan and Seoul. The results here were inferred from surface NO2 and O3 observations, and the varification studies based on in-situ VOCs measurements would be needed.

Mulberries have importance in the sericulture industry as food for Bombyx mori, silkworm reared for its silk. Korean Morus alba have many cultivars and, for the protection of these cultivars and for utilization in plant-breeding programs, genetic information and the diversity among cultivars are essential. This study with 14 mulberry genotypes was undertaken using RAPD and ISSR fingerprinting to discover the genetic divergences between cultivars. Polymorphism rate among the cultivars produced by RAPD primer was found to be 64.48% and 66.29% relative to ISSR primer. The genetic relationships among the cultivars were identified using a dendrogram constructed with the UPGMA clustering method. Nei's method was used to calculate the genetic dissimilarity coefficients between each pair of genotypes, and the highest dissimilarity coefficient of 0.246 was exhibited between Suwon and Hwanggum cultivars. To determine the efficiency of each primer, a polymorphic index was calculated, and the robustness of the dendrogram was checked using cophenetic correlation coefficient. The results of this study can be utilized for the improvement of mulberry varieties in plant-breeding programs.

In this study, a river basin with a lot of measured data such as water level, flow rate, current speed, and sediment rate from the past to now was selected and geometrical shape of a pier was re-analyzed, in order to study the effects of the flow around the pier area as well as the riverbed alternation characteristics. A finite element mesh of the entire river was prepared, and via parameter revision, the section that the pier has influence on was decided, to analyze the shape of the pier using RMA-2 and SED2D-WES models. With regards to the section that the pier has influence on, analysis was done on the four pier shapes, namely circle, square, rectangle, and octagon. The results showed that the shape with the least influence around the pier around is the octagon, followed by circle, rectangle, and square, showing the different geometrical effects that the shapes have on the pier. Furthermore, it was shown that the distribution of sediment concentration had effect from about (+)110 m of the upstream to about (-)130 m of the downstream, from the pier installation point. Also, it was shown after analyzing drag forces for different sediment particle distributions that the shape with the greatest drag is the octagon, followed by circle, square, and rectangle.

The purpose of this study is to analyze the sensitivity of the RMA2 model parameters reflecting the flow characteristics of stream junction and thus understand the hydraulic characteristics of the channel confluence flow. This study dealt with the input parameters of the RMA-2 model, a two-dimensional numerical analysis model widely used for researches both at home and abroad. The parameters of the RMA-2 model are roughness coefficient, turbulent diffusion coefficient, Coriolis forces latitude, Density, and mesh size. This study those parameters estimated from actual heavy rainfall, and varied the parameter size by (-)30%～+30% to review the characteristics of the flow characteristics of the channel section. Weobserved that when the ratio of the channel width was relatively small, the smaller the approaching angle was, the farther from the junctions became the generating place of the maximum flow velocity, however, when the ratio of the channel width was relatively large, the larger the approaching angle was, the farther the generating place of the maximum flow velocity from the junctions became. In particular, the distance between junctions and the place where the maximum flow velocity generated showed an absolute correlationover 90% of the relative channel width, but an inverse relationwas found when the distance to the place where the flow velocity generated was shortened as relative the channel width between the main channel and tributary increased.

The purpose of this study is to examine appropriate sub-basin division numbers that best reflect the hydrological characteristics of the basin so as to propose the criterion for dividing the sub-basin in analyzing flood runoff in the future. The characteristics of flood runoff variations were based on the WMS HEC-1 model, and the area in the upstream of the Dongbyeon water level observatory and the Geum-ho water level observatory was chosen for analysis, and examined the characteristics of the changes in flood runoff. First of all, in the targeted basin, if the sub-basin division number was 4 (that is, the area of the divided sub-basin was about 25% of the total area). Next, as the sub-basin division number gradually increased, the peak rate of runoff increased as well, and in case the sub-basin was not divided, the peak rate of runoff occurred at the earliest time. Given these results, the spatial change characteristics will be best reflected when the sub-basin is divided for analysis of flood runoff in such a way that the area of the divided sub-basin is about 25% of the total area of the basin. However, as these results are based on a limited number (4) of storms, more storm events and other basins need to be included in the review of the sub-basin division methodology.

Persicaria thunbergii has been utilized for the treatment of cancer as a folk medicine. We examined the effect of isorhamnetin, a flavonoid isolated from Persicaria thunbergii, on angiogenesis in vitro and in vivo. Basic fibroblast growth factor (bFGF) is a potent angiogenic factor found in various tumors. In this study, we found that the isorhamnetin decreased bFGF-induced human umbilical vein endothelial cells (HUVECs) proliferation and migration in a concentration-dependent manner (5, 10 and 20 μM) whereas, it did not inhibit bFGF-induced capillary-like formation of HUVECs. The chicken chorioallantoic membrane assay revealed that addition of isorhamnetin (10, 20 and 40 μM) displayed an antiangiogenic effect in vivo. These results suggest that the isorhamnetin inhibits the proliferation and migration of endothelial cells induced by bFGF, which may explain its anti-angiogenic properties.