• The Korean Journal of Ecology
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• 제18권1호
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• pp.1-15
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• 1995

Alakline phosphatase activity (AP A) as a phosphorus deficiency measurement in flowing waters and of microhabitats (rocks, wood, leaves, and sediments) was measured and its relationship to flux of nutrients and response to rainfall events were determined for two geologically different streams in west Alabama from August to November. Results indicated water column AP A in both streams had a low correlation with levels of orthophosphate, total organic phosphorus, nitrate, ammonia, dissolved organic carbon, and discharge (r=0.075-0.583; n=g-IU. Communities on rock surfaces showed a higher AP A level than those on wood and leaves. Sediment passed through a $106{\mu}m$ sieve showed 2-9 times higher AP A level than material passed through $425{\mu}m$ sieve. The first storm after drought at Yellow Creek introduced substantial quantities of DOC (2.5 times baseflow concentrations) and $N0_3-N$ (5.8 times baseflow concentrations) which did not affect AP A significantly. The second storm at Little Schultz Creek caused minor changes in nutrient cocentrations; however $N0_3-N$ levels and AP A were drastically lower due to the dilution effect. Retention of stream water AP A at Yellow Creek and Little Schultz Creek on $0.45{\mu}m$ filter (54 and 43%, respectively) and $0.22{\mu}m$ (83 and 77% of total APA. respectively) indicated more free dissolved portion of the enzyme was present at Little Schultz Creek. Little Schultz Creek (with carbonate and with a higher productivity and biomass) showed a consistantly greater AP A activity $(132{\pm}54\;{\mu}M{\cdot}1^{-1}{\cdot}min^{-I};\;n=g)$ than Yellow Creek $(41{\pm}23\;{\mu}M{\cdot}1^{-I}{\cdot}min^{-I}$, with a sandstone substrate; n=l1, $p{\leq}O.OO1)$. Overall, a greater APA on all microhabitats and the presence of more dissolved enzyme in Little Schultz Creek during the study period may indicates it is more P deficient than Yellow Creek.

• 한국토양비료학회지
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• 제49권5호
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• pp.409-419
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• 2016

With increasing social concerns for healthy food, the studies on the cultivation of crops to increase accumulation of functional metabolites in crops have been investigated. Accumulation of the metabolites in crops is highly affected by various types of stress, such as nutrient deficiency, water deficit (WD), extreme temperature and UV-B radiation as well as their own life cycle. This review summarizes the previous studies on the effects of environmental stresses, especially WD and UV-B radiation, on accumulation of functional metabolites in crops. UV-B radiation and WD during specific period (mainly at maturation stage) activates the adaptation and/or defense system in crops, thereby increasing biosynthesis of the metabolites. Although WD and UV-B radiation tend to decrease in crop yield, the decrease can be compensated by the production of high value crops having high content of functional metabolites.

• 대한지역사회영양학회지
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• 제16권1호
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• pp.14-22
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• 2011

This study was designed to compare the incidence and severity of premenstrual syndrome (PMS) between normal (N = 85) and overweight or obese (N = 28) college female students and investigated correlation between PMS, nutrient intake, hematological index and psychological index (depression, anxiety, stress). Each subject was asked a Menstrual Discomfort Questionnaire (MDQ) for PMS by 5 Likert scale. The PMS scores of women in the normal weight subjects ranked in order of severity were water retention (2.71), followed by behavioral change (2.58), negative affect (2.46), pain (2.31), autonomic reaction (2.27), decreased concentration (2.16). The symptoms of 'pain' and 'behavioral change' of overweight or obese subject were significantly higher than those of normal subject (p < 0.05). And total cholesterol concentration of overweight or obese subjects was significantly higher than in normal subject (p < 0.05). There was a significant positive correlation (p < 0.05) between the symptoms of 'negative effect' and BMI. And the triglyceride concentration was positively related with 'water retention (p < 0.01)'. The symptoms of 'decreased concentration' were negatively correlated with calcium (p < 0.01) and vitamin B6 intake (p < 0.05). The depression score were positively related with symptoms of 'behavioral change (p < 0.05)', 'negative affect' (p < 0.01), and the anxiety score was positively correlated with 'behavioral change (p < 0.05)' and 'decreased concentration (p < 0.05)'. The stress score was positively correlated with 'decreased concentration (p < 0.01)', 'behavioral change (p < 0.05)' and 'negative affect (p < 0.05)'. This suggests that PMS represents the clinical manifestation of a calcium, vitamin $B_6$ deficiency and psychological disorder. Therefore we concluded that nutrient supplementation, depression and stress management may help to relieve PMS symptoms.

• 한국수산과학회지
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• 제36권1호
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• pp.65-67
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• 2003

Flounder (Paralichthys olivaceus) fish goes through metamorphosis in the larvae phase. In this phase, it secretes much thyroid hormone to control metamorphosis. Sharp change in the environment and nutrition deficiency may cause stress in the metamorphosis phase. It leads to interfering with the development of thyroid hormone and finally inhibits the normal growth of larvae. In this study, the correlation between the change in thyroid hormones and the albinism appearance was examined by growing them with low temperature ($13^{\circ}C$) stress over the premetamorphosis stages (stage $D\~F$) of flounder metamorphosis. Albinism rate was $15\%$ in the low temperature group and $25\%$ in the control goup. $T_{4}\;and\;T_{3}$ of the control group tended to increase from stage F as larvae grew. $T_{4}$ increased 2 times compared to the control group as 72 ng/g at stage H, the increasing phae of water temperature, in the low temperature group. $T_{3}$ increased 8 times compared to the control group as 2.9 ng/g at stage E, the decreasing phase of water temperature. Therefore, it is judged that the albinism appearance of flouner is caused from the sharp increase in $T_{3}$ by the inappropriate secretion of thyroid hormone.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.83-83
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• 2016

가뭄은 발생과정과 피해영향에 따라서 기상학적, 농업적, 수문학적, 사회경제적 가뭄으로 구분되고 있다. 강수의 부족은 기상학적 가뭄을 발생시키고, 기상학적 가뭄이 지속되면 토양수분 부족으로 농작물의 피해를 가져오는 농업적 가뭄이 나타난다. 이어서, 지표 및 지표 아래의 수자원량이 평년수준 이하로 감소하면서 수문학적 가뭄이 발생한다. 이와 같이 다른 종류의 가뭄으로 가뭄이 변화하는 현상을 가뭄 전이(Drought Propagation)라고 한다. 강수량의 부족만으로 판단되는 기상학적 가뭄은 가뭄 상황의 판단은 간단지만, 체감으로 느끼는 가뭄과 차이가 존재한다. 수문학적 가뭄은 실제 물이용과 관련이 높아 효율적인 물 관리를 위해서는 수문학적 가뭄에 대한 정보가 필요하다. 하지만 수문학적 가뭄은 기상학적 인자들뿐만 아니라 수문순환과정의 영향을 받아 가뭄의 발생과정이 복잡하기 때문에 판단 및 예측이 어렵다. 본 연구에서는 가뭄의 전이관계를 도출함으로써, 기상학적 가뭄에서 수문학적 가뭄으로 발전되는 가뭄의 크기를 파악하고자 한다. 가뭄은 판단기준에 따라서 다양하게 정의될 수 있다. 본 연구에서는 기상학적 가뭄은 강우량으로, 수문학적 가뭄은 유역별 댐의 저수율, 유입량 및 지하수위를 활용하여 가뭄을 정의하며, 가뭄사상은 임계수준방법(threshold level approach)과 풀링기법(pooling method)을 수문기상 변수들에 적용하여 추출하였다. 수문학적 가뭄은 기상학적 가뭄이 발생한 이후, 가뭄 상황이 일정기간 지속되는 상황에 발생하는 결과가 확인되었다. 기상학적 가뭄에서 수문학적 가뭄이 전이되는 현상을 바탕으로 기상학적 가뭄의 상황에 따라서 미래의 수문학적 가뭄의 변화 양상에 대하여 예측가능하며, 가뭄의 전이관계는 수문학적 가뭄의 예측을 위한 자료로 활용될 수 있을 것으로 판단된다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.156-156
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• 2016

2016년 2월 5일, 짐바브웨는 극심한 가뭄으로 인해 인구의 4분의 1이상이 식량난을 겪고 있다며 '국가 재난 사태'를 선포하였다. 한때 아프리카 곡창지대로 불리던 짐바브웨가 극심한 가뭄을 겪게 된 데에는 2015/16년 슈퍼엘니뇨의 영향이 크게 한 몫을 하였는데, 이는 남반구의 여름인 11월부터 이듬해 3월까지인 짐바브웨의 우기가 2015/16년 슈퍼엘니뇨 강도가 절정에 달했던 시기(10월에서 2월)와 겹쳐져 짐바브웨의 강수량이 슈퍼 엘니뇨의 영향을 받게 되었기 때문이다. 게다가 4월부터는 엘니뇨의 영향을 받은 우기가 끝나고 건기가 시작되기 때문에 앞으로 가뭄이 얼마나 더 악화될지 우려되는 상황이다. 짐바브웨의 기후를 살펴보면, 증발량이 강수량보다 많은 건조기후 중에서도 비교적 그 정도가 약한 기후인 반건조 지대에 속한다. 하지만 연강수량 변동에 따라서, 비가 내리는 해에는 토양 수분이 과잉되고 비가 적게 내리는 해에는 심한 물 부족 현상이 일어나게 되기 때문에, 건기가 시작되는 4월부터 짐바브웨 강수 예측은 가뭄이 얼마나 지속될지를 파악하는 데에 아주 중요한 요소가 될 수 있다. 따라서 본 연구에서는 강수 예측 결과를 중심으로 2016년 짐바브웨의 가뭄이 얼마나 지속되고, 또 가뭄의 강도는 어떻게 될지 알아보는 것에 목적을 두고, GCM을 이용하여 2016년 3월에서 10월까지 장기예측을 수행하였다. 경계 자료로는 ECMWF (European Centre for Medium Range Weather Forecasts)에서 제공하는 Sea Ice자료와, NOAA OI (National Oceanic and Atmospheric Administration Optimum Interpolation) Weekly SST자료를 사용하였고 엘니뇨의 영향을 고려하기 위해 IRI (International Research Institute)의 ENSO forecast를 참고하여 SST아노말리에 월별 가중치를 적용하였다. 초기 입력 자료로는 1월 21-30일 10일간의 ECMWF의 재분석 자료를 이용하여 총 10개 멤버의 앙상블 예측을 수행하였고, 8개월(3-10월) 기간에 대해 약 한 달간의 spin-up time을 주었다. 예측 자료를 모델 climatology와 비교하여 월 평균 강수 전망을 분석하였고, 기온과 해면기압의 월 평균자료도 추가 분석하였다. 또한 짐바브웨 지역의 강수 관측 자료와 모델 예측 자료를 이용하여 특정 도시들의 1년 누적강수를 예측 및 분석하였고, 최종적으로 이 결과를 통해 짐바브웨의 가뭄지속가능성을 살펴보았다.

• 대한약침학회지
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• 제24권1호
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• pp.24-31
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• 2021

Objectives: Accumulation of cellular reactive oxygen species (ROS) leads to oxidative stress. Increased production of ROS, such as superoxide anion, or a deficiency in their clearance by antioxidant defences, mediates cellular pathology. Grewia Spp fruits are a source of bioactive compounds and have notable antioxidant activity. Although the antioxidant capacity of Grewia Spp has been studied, there is very limited evidence that links the antioxidant activities of Grewia bicolor and Grewia flava to the inhibition of free radical formation associated with damage in biological systems. Methods: This study evaluated the protective effects of Grewia bicolor and Grewia flava extracts against free radical-induced oxidative stress and the resulting cytotoxicity effect using HeLa cells. Antioxidant properties determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and total phenolic content (TPC) assays showed significantly higher (p < 0.05) antioxidant activity in Grewia flava (ethanol extract) than Grewia flava (water extract) and Grewia bicolor (ethanol and water extracts). Results: Using 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide or MTT assay, cytotoxicity results showed that extracts of Grewia bicolor and Grewia flava were less toxic to HeLa cells at tested concentrations compared to the untreated control. This confirmed the low toxicity of these edible fruits at the tested concentrations in HeLa cells. Furthermore, hydrogen peroxide (H2O2)-induced cell loss was effectively reduced by pre-incubating HeLa cells with Grewia bicolor and Grewia flava extracts, with Grewia flava (ethanol extract) revealing better protection. Conclusion: The effect was speculated to be associated with the higher antioxidant activity of Grewia flava (ethanol extract). Additional studies will warrant confirmation of the mechanism of action of such effects.

• 대한한의학원전학회지
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• 제35권4호
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• pp.97-114
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• 2022

Objectives : Background research on the history of Huangbo's taste being written as 'pungent' was undertaken, after which its clinical meaning was examined from the medical perspective that was behind the medicinal's taste designation. Furthermore, through various understandings on the 'pungent' taste within the process of clinical application, the meaning of 'pungent' in Korean medicinal research was re-evaluated. Methods : Description of Huangbo's taste as 'pungent' as written in medical texts were chronologically examined to determine its origin. The clinical meaning of the pungent taste of Huangbo was examined within the broad medical perspective of doctors who were behind these descriptions. Results & Conclusions : The pungent taste of Huangbo was first described by Zhang Yuansu, followed by doctors of the Yishui School such as Li Dongyuan, Wang Haogu, etc., during which such knowledge was established and contributed to recognition of Huangbo's effect as tonifying Kidney deficiency and treatment of fire within water, after reaching the Kidney. Li Dongyuan understood the meaning of Huangbo's pungent taste as eliminating Yin fire and restoring the upward direction, ultimately restoring the general 'Rising-Falling-Floating-Sinking' mechanism within the context of his inner damage treatment. On the other hand, Zhu Danxi interpreted the pungentness of Huangbo based on his understanding of the nature of fire and action towards it. It seems as Huangbo's effects were understood within a relatively narrow frame, application of its pungent taste became vague, which gave rise to criticism by later period doctors, ultimately leading to an ambiguous understanding of the pungent taste of Huangbo.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.442-442
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• 2008

Hydrogen was produced by water plasma excited in very high frequency inductively coupled tube reactor. Mass spectrometry was used to monitor gas phase species at various process conditions. Water dissociation rate depend on the process parameters such as ICP power, flow-rate and pressure. Water dissociation percent in ICP reactor decrease with increase of chamber pressure and $H_2O$ flow rate, while increase with increase of ICP power. In our experimental range, maximum water dissociation rate was 65.5% at the process conditions of 265 mTorr, 68 sccm, and 400 Watt. The effect of $CH_4$ addition to a water plasma on the hydrogen production has been studied in a VHF ICP reactor. With the addition of $CH_4$ gas, $H_2$ production increases to 12% until the $CH_4$ flow rate increases up to 15 sccm. But, with the flow rate of $CH_4$ more than 20 sccm, chamber wall was deposited with carbon film because of deficiency of oxygen in gas phase, hydrogen production rate decreased. The main roles of $CH_4$ gas are to reacts with O forming CO, CHO and $CO_2$ and releasing additional $H_2$ and furthermore to prevent reverse reaction for forming $H_2O$ from $H_2$ and $O_2$. But, $CH_4$ addition has negative effects such as cost increase and $CO_x$ emission, therefore process optimization is required.

• 한국토양비료학회지
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• 제4권2호
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• pp.137-141
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• 1971

토양(土壤)의 첨가(添加)가 화훼액비(花卉液肥), 유박(油粕)(참깨묵)의 부숙(腐熟) 및 비효에 미치는 영향을 밝히고저 실험실내(實驗室內)에서 한개의 부숙시험(腐熟試驗)을 실시(實施)하는 외(外)에, Petunia hybrida를 표식식물(標識植物)로 분재배(盆栽培)를 하였다. 표식식물(標識植物)은 4엽(葉)이 나왔을 때 이식(移植)한 것이며, 비료(肥料)는 추비(追肥)로만 시용(施用)했는데, 시험결과(試驗結果)는 다음과 같다. 1. 유박(油粕)에 토양(土壤)을 혼합(混合)하여 담수(湛水)한 것이 토양(土壤)의 첨가(添加)없이 담수(湛水)한 것보다 부숙(腐熟)이 빠르고 더 많은 암모니아태질소(態窒素)를 생성(生成)했으며, Petunia hybrida에 대한 비효도 컸다. 토양(土壤)의 첨가(添加)는 담수초기(湛水初期)에 혼합물(混合物)의 pH를 높임으로써 뒤따르는 유박(油粕)의 분해(分解)를 촉진(促進)한 것으로 생각되었다. 2. 야간온도(夜間溫度)가 때로는 $15^{\circ}C$ 이하(以下)에 달(達)하는 저온(低溫)에서는 부숙액(腐熟液)의 pH가 상승(上昇)하지 않고 암모니아태질소(態窒素)의 생성(生成)의 고온(高溫)($30^{\circ}C$)에서 보다 현저히 낮았다. 그러나 토양(土壤)을 첨가(添加)하여 부숙(腐熟)시킨 것이 그렇게 하지 않았던 것보다 많은 암모니아를 생성(生成)했고, Petunia hybrida의 생육(生育)에도 좋은 영향을 주었다.