• 생명과학회지
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• 제17권8호통권88호
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• pp.1104-1110
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• 2007

2005년 5월부터 2006년 3월까지 안동호와 임하호의 어류상과 서식하는 어종인 끄리(Opsariichthys uncirostris amurensis), 백조어(Culter brevicauda) 그리고 치리(Hemiculter eigenmanni)의 길이-무게 상관관계에 관한 조사 결과를 실시하였으며 결과는 다음과 같다. 조사된 어류는 안동호와 임하호 각각 7과 20종 2,540개체, 4과 11종 850개체였으며, 끄리, 백조어, 치리의 개체수는 안동호에서 총 486개체, 임하호에서는 총 124개 체로 조사되었고, 이들 공서 어류는 길이가 비슷한$({\pm}2.5$ mm) 171개체를 비교하였다. 안동호에 서식하는 끄리, 백조어, 치리의 길이-무게 상관관계식은 각각 TW = $0.000007TL^{3.0543}$, TW = $0.0000009TL^{3.3654}$, TW = $0.000001TL^{3.3872}$로 나타났으며, 임하호에서는 각각 TW = $0.00002TL^{2.8493}$, TW = $0.00001TL^{2.8744}$, TW = $0.000004TL^{3.1082}$로 나타났다. 비대지수에서는 안동호에서는 3종 모두 기울기가 양의 값으로 영양상태가 양호한 것으로 나타났으나, 임하호에서는 치리를 제외한 2종에서 기울기가 음의 값을 나타내어 영양상태가 좋지 않은 것으로 나타났다. 상대적 비대지수를 알아본 결과 끄리와 백조어에서 안동호의 개체가 임하호의 개체보다 비대한 경향을 보였으며, 치리는 임하호의 개체가 더 비대한 것으로 나타났다.

• 한국자기학회지
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• 제5권5호
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• pp.735-739
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• 1995

An experiment was carried out to investigate the effect of $Na_{2}O$ additive on the magnetic and physical properties of $SrZn_{2}-W$ type hexagonal ferrite. The specimens were prepared by the conventional manufacturing methods without atmosphere control. It was found that the magnetic properties of SrO.2ZnO.$8Fe_{2}O_{3}$ are considerably improved on adding 1.5wt% $Na_{2}O$. Theoptimum condition of making magnet with suitable properties are as follows : chemical analysis composition : $Sr^{2+}_{0.852}Zn^{2+}_{1.721}Na^{+}_{0.301}Fe^{2+}_{0.723}Fe^{3+}_{15.703}O_{27}$ ; semisintering condition : $1300^{\circ}C\;{\times}\;1h$ in air ; sintering condition : $1250^{\circ}C\;{\times}\;0.5h\;T_{c}=371^{\circ}C,\;H_{A}=1091.5kA/m,\;K_{A}=2.13{\times}10^{5}J/m^{3}\;and\;n_{B}=31.8\mu\textrm{B}$.

• The Korean Journal of Physiology and Pharmacology
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• 제6권4호
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• pp.183-186
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• 2002

Ischemic damage is one of the most serious problems. The openers of KATP channel have been suggested to have an effect to limit the ischemic damage. However, it is not yet clear how KATP channels of a cell correspond to hypoxic damage. To address the question, N2a cells were exposed to two different hypoxic conditions as follows: 6 hours hypoxia followed by 3 hours reperfusion and 12 hours hypoxia followed by 3 hours reperfusion. As the results, 6 hours hypoxic treatment increased glibenclamide- sensitive basal $K_{ATP}$ current activity (approximately 6.5-fold at 0 mV test potential) when compared with nomoxic condition. In contrast, 12 hours hypoxic treatment induced a relatively smaller change in the $K_{ATP}$ current density (2.5-fold at 0 mV test potential). Additionally, in experiments where $K_{ATP}$ channels were opened using diazoxide, the hypoxia for 6 hours significantly increased the current density in comparison to control condition (p＜0.001). Interestingly, the augmentation in the $K_{ATP}$ current density reduced after exposure to the 12 hours hypoxic condition (p＜0.001). Taken together, these results suggest that $K_{ATP}$ channels appear to be recruited more in cells exposed to the 6 hours hypoxic condition and they may play a protective role against hypoxia-reperfusion damage within the time range.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.639-642
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• 2004

The pH as a control parameter for oxidation-reduction potential (ORP) was investigated through the denitrification by Ochrobactrum anthropi SY509 under non-growing condition. The optimal pH of nitrate reductase was 7.0, and the minimal ORP level was －250 mV for the denitrification under aerobic condition. In the case of anaerobic condition, the optimal pHs of nitrate and nitrite reductase were shifted to 10.0 and 9.0, respectively, and the minimal ORP levels of nitrate and nitrite reductase were decreased to －370 mV and －340mV, respectively. In the case of alkaline pH and anaerobic condition, the denitrification efficiency of nitrate was increased up to about 2-fold over that of neutral pH and anaerobic condition. Therefore, the combined control of pH and ORP in the anaerobic condition is shown to be an important parameter in the biological denitrification process.

• 한국토양비료학회지
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• 제19권2호
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• pp.153-156
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• 1986

수온 및 지온변화에 단독(單獨) 또는 혼합(混合) 서식(棲息)하는 좀개구리밥, 붕어마름 및 조류등(藻類等)이 미치는 영향(影響)을 구명(究明)코자 1/200a 대형무저토관(大型無底土管)에서 조사연구(調査硏究)한 결과(結果)는 다음과 같았다. 1. 담수토양(湛水土壤)의 일중(日中) 최고수온 및 지온은 좀개구리밥 서식지(棲息地)가 무서식지(無棲息地)보다 $1{\sim}3^{\circ}C$정도(程度) 낮았으나 최저수온 및 지온은 같거나 $0.5^{\circ}C$정도(程度) 높았다. 2. 담수토양(湛水土壤)의 천기별(天氣別) 수온 및 지온은 좀개구리밥 서식지(棲息地)가 무서식지(無棲息地)보다 맑은 날은 $0.1{\sim}0.3^{\circ}C$ 낮았으나 구름 강우(降雨) 개임시(時)는 $0.1{\sim}0.4^{\circ}C$정도(程度) 높았다. 3. 조류서식(藻類棲息) 담수토양(湛水土壤)의 수온 및 지온은 무서식지(無棲息地)보다 $0.3{\sim}1.0^{\circ}C$ 높아 조류(藻類)에 의한 보온효과가 認定되었다. 4. 잡초서식(雜草棲息) 형태별(形態別) 수온 및 지온 보존(保存) 효과는 붕어마름 단독서식(單獨棲息)>혼합서식(混合棲息)>분개구리밥 단독서식(單獨棲息)>무서식(無棲息) 순(順)으로 높았다.

• Imaging Science in Dentistry
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• 제35권2호
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• pp.97-103
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• 2005

Purpose : To determine if ultrasonography is a reliable technique to assess masseter muscle sites within intra- and interobserver and the scanning level and/or the muscle condition affect local cross-sectional dismension (LCSD) measurements of masseter muscle. Materials and Methods : 10 subjects without sign and symptom of temporomandibular disorders and missing posterior teeth were examined by ultrasonography. Bilateral ultrasonographic examinations were performed with a linear (B-scan) 7.5 MHz small-part transducer to register LCSDS of the masseter muscle on three different levels. Scans were made on relaxed and clenching condition. Three oral and maxillofacial radiologists measured at two sessions with a time interval of at least 5 minutes. Results : Variables such as 'condition' and 'level' had a significant effect on muscle measurements (p<0.05). There was no significant difference between 'sessions'(p>0.05) and 'observers' (p>0.05). LCSDS on lower scan level were significantly thinner than those on upper and middle level. Those on clenching condition were significantly thicker than those on relaxed condition (p<0.05). The scanning level with the highest reproducibility was middle with clenching condition (ICC=0.90, $MSE=0.55\%$). Conclusion : The data suggested that ultrasonography was a reliable method for measuring LSCD of masseter muscle in intra- and Interobserver and middle scan level showed the most reliable data.

• 대한수학회지
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• 제47권6호
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• pp.1317-1328
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• 2010

In this paper, we study the properties of positive solutions for the reaction-diffusion equation $u_t$ = $\Delta_u+{\int}_\Omega u^pdx-ku^q$ in $\Omega\times(0,T)$ with nonlocal nonlinear boundary condition u (x, t) = ${\int}_{\Omega}f(x,y)u^l(y,t)dy$ $\partial\Omega\times(0,T)$ and nonnegative initial data $u_0$ (x), where p, q, k, l > 0. Some conditions for the existence and nonexistence of global positive solutions are given.

• 한국산업보건학회지
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• 제25권2호
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• pp.174-183
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• 2015

Objectives: The objective of this study is the estimation of factors influencing airborne fiber concentrations by means of an observation survey of asbestos-containing materials in buildings. Methods: Forty-five samples were collected from four commercial buildings by NIOSH Method 7400 and classified according to current condition, potential activity, construction year, and operations and maintenance(O&M). Results: Airborne fiber concentrations by current condition(classified as good, fair and poor) were significantly different(p<0.05). Concentrations by potential activity were significantly different among groups(p<0.05), and those from the low activity group were higher than those from the middle activity group. Based on construction year, airborne fiber concentrations from the decade of the 1990's were higher than those from the 1960's. When O&M status was considered, airborne fiber concentrations from 1960's buildings were lower than those buildings not operated and maintained(p<0.01), because dust generation was influenced by O&M status. It was found that airborne fiber concentrations were related to current condition and potential activity via regression analysis, but the coefficient of determination was low. Also, correlation analysis showed that the higher the potential activity, the more current condition is worsened, but the relationship was not significant(r=-0.455, p>0.05). Conclusions: Airborne fiber concentrations in asbestos-containing buildings had weak relationships with current condition and potential activity.

• 한국치위생학회지
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• 제13권1호
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• pp.89-97
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• 2013

Objectives : For investigating relationship between oral condition and body mass of adolescent period and helping to make basic data which make oral care systematically while performing health care for adolescent. Methods : This research was carried out by performing oral and physical test of 273 high school students in some reasons from July 2nd to 16th in 2012. Results : There were significant differences, since the more subjects had irregular occlusion, the more they had loosing tooth(p<0.05). There was a significant difference, since when subjects had more numbers of regular occlusion, they had higher BMI and heavier weight.(p<0.001). There are significant different, since when the subjects had worse peridontal condition, they had more numbers of DT(p<0.001). There was a significant difference in occlusion and body mass group, since when subjects had regular occlusion, 46.4% of subjects were standard body weight, 41.0% of subjects were overweight and when subjects needed orthodontics, 52.7% of subjects were standard body weight, 33.8% of subjects were low-weight, and 13.5% of subjects were overweight(p<0.001). In the correlation between oral condition and BMI, DT index showed negative interrelation with FT index(r=-0.179) and positive interrelation with periodontal condition(r=0.221), MT index showed positive interrelation with occlusion(r=0.137) and FT index showed positive interrelation with height(r=0.136). BMI showed highly positive interrelation with weight(r=0.940), and when occlusion was worse, it shows negative interrelation with BMI(r=-0.293). Height showed highly positive interrelation with weight(r=0.447), and when the more subjects had malocclusion, it showed low negative interrelation with weight (r=-0.257). Conclusions : It was considered that an adolescent period forms health habits, so it was important to increase health action through education for growing healthy adult and not only guiding improvement of dietary life for keeping normal weight, but also conducting oral health education for treating regular occlusion of oral condition and prosthetic procedures for loosing tooth right time.

• 한국식품저장유통학회지
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• 제8권4호
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• pp.412-418
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• 2001

본 연구에서는 현미의 무증자 알콜발효조건을 설정하고자 반응표면분석으로 알콜발효조건을 모니터링하였다. 그 결과 무증자 알콜발효에 적합한 S. cerevisiae GRJ를 선발할 수 있었다. 알콜함량, brix, pH 및 총산에 대한 회귀식의 $R^2$는 각각 0.8828, 0.8409, 0.9431 및 0.9280이였다. 무증자 알콜발효에서 알콜함량의 최대치는 효소제 함량 0.34%(w/w) 및 가수량 350(v/w)의 범위에서 얻을 수 있었다. 최적조건에서 실제 실험값과 예측값들은 유사한 경향을 나타내었다..