• 대한의생명과학회지
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• 제23권2호
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• pp.144-153
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• 2017

It was demonstrated that Gangjihwan (DF), which is the herbal composition composed of Ephedra intermedia, Lithospermum erythrorhizon, and Rheum palmatum, inhibits obesity and hepatic steatosis in high fat diet (HFD)-fed obese mice. The aim of this study was to determine the effects of DF on visceral obesity, hepatic inflammation and fibrosis and the mechanism of actions involved in this process using in vivo and in vitro approaches. DF was extracted with water (DF-FW), 30% grain alcohol (DF-GA30), and 70% grain alcohol (DF-GA70). Administration of DF to HFD-fed control mice decreased visceral tissue mass and visceral adipocyte size without adverse effects. Visceral fat mass was decreased by DF-GA30 and DF-GA70, and visceral adipocyte size by all three DF extracts compared with obese control mice. Histological analysis revealed that three kinds of DF extracts reduced toluidine blue-stained mast cells and collagen accumulation in the liver, the extents of which were most eminent in DF-GA70-treated mice. DF-GA70 decreased the mRNA levels of the inflammation ($TNF{\alpha}$ and VCAM-1), fibrosis (${\alpha}-SMA$), and apoptosis (caspase 3) genes, but increasing the anti-apoptosis gene (Bcl-2) mRNA levels in the liver of obese control mice. Consistent with the in vivo data, GA-70 also altered the expression of inflammation genes ($TNF{\alpha}$ and MCP-1) in HepG2 cells. These results indicate that DF not only inhibits visceral obesity, but also ameliorates visceral obesity-induced hepatic inflammation and fibrosis and that this process may be mediated by regulating the hepatic expression of inflammatory and fibrogenic genes.

• 대한화학회지
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• 제28권1호
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• pp.26-33
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• 1984

HF와 DF 혼합계내에서 일어나는 다음 두 진동-진동 에너지 이동 반응의 속도상수$(k_{vv})$를 n=2~5에 대해 300~800K 온도 범위에서 이론적으로 계산하였다. HF(v=n) + DF(v=0) ${\to}$ HF(v=n-l) + DF(v=l) + ${\Delta}E$(a) DF(v=n) + HF(v=0) ${\to}$ DF(v=n-l) + HF(v=l) + ${\Delta}E$(b) 이용한 충돌모형은 수소결합에너지를 분자간 상호작용의 주축으로 삼는 loosely-held, non-rigid dimer model이었고, 계산법으로는 반고전적 방법을 사용하였다. 계산 결과 반응(a)에 대한 속도상수가 반응(b)에 대한 속도상수 보다 훨씬 HF-DF 혼합계 내에서는 진동에너지가 HF에서 DF로 이동함이, 또한 반응(a)에 대한 속도 상수는 온도가 높아질 수록 감소하고, 진동 양자수가 커질 수록 증가하는 반면에, 반응 (b)에 대한 속도 상수는 온도 의존성과 양자수 의존성에 있어서 대체로 이와 반대의 경향을 보임을 밝혔으며, 이 계산 결과는 주로 에너지 차 ${\Delta}E$의 부호와 크기로써 설명될 수 있음을 보였다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제21권4호
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• pp.289-296
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• 2018

Purpose: We aimed to study the pattern of liver-injury in children with dengue fever (DF) and validate serum aminotransferase ${\geq}1,000IU/L$ as a marker of severe DF. Methods: Children admitted with DF were included. DF was defined by presence of clinical criteria and positive serological or antigen tests in absence of other etiology. DF severity was graded as dengue without or with warning signs and severe dengue. Liver-injury was defined as alanine aminotransferase (ALT) more than twice the upper limit of normal (boys, 30 IU/L; girls, 21 IU/L). Results: Of 372 children with DF, 144 (38.7%) had liver-injury. Risk of liver-injury and aminotransferase levels increased with DF severity (p<0.001). Recommended ALT and aspartate aminotransferase (AST) cut-off at ${\geq}1,000IU/L$ had sensitivity 4.8% (5/105), specificity 99.3% (265/267) for detection of severe DF. In children with ALT and AST <1,000 IU/L (n=365), the area under receiver operating curves for prediction for severe DF, were 0.651 (95% confidence interval [CI], 0.588-0.714; p<0.001) for ALT and 0.647 (95% CI, 0.582-0.712; p<0.001) for AST. Serum ALT at 376 IU/L and AST at 635 IU/L had sensitivity and specificity comparable to ${\geq}1,000IU/L$ for defining severe DF. Conclusion: Liver-injury is common in DF. The ALT and AST levels increase with DF severity. ALT and AST levels of ${\geq}1,000IU/L$ could be lowered to 376 IU/L and 635 IU/L respectively for defining severe DF.

• 한국화재소방학회논문지
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• 제32권4호
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• pp.7-16
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• 2018

본 연구에서는 CFAST를 이용하여 구획실 가스연료 화재실험에 대한 디자인 화재곡선(Design fire curves, DF)의 예측성능을 평가하였다. 평가된 디자인 화재곡선은 이전의 연구에서 제안된 2-stage DF, Ingason이 제안한 Quadratic DF와 Exponential DF이며, 예측성능 평가를 위해 각 디자인 화재곡선을 CFAST의 입력조건으로 하여 시뮬레이션을 수행하였다. 시뮬레이션결과와 실험결과의 비교를 통해 구획실 내부의 공간평균온도와 $O_2$, $CO_2$ 농도에 대해 전반적으로 2-stage DF > Quadratic DF > Exponential DF 순으로 실험결과를 합리적으로 예측하는 것을 확인하였다. CFAST 시뮬레이션 결과를 통해서도 실험에서 보이는 구획실 내 개구부측과 내측에서의 온도와 $O_2$ 및 $CO_2$ 농도 차이를 예측할 수 없음을 명확히 확인하였다. 또한 CFAST는 구획실 가스연료 화재의 CO 농도와 하층부의 공간평균온도에 대한 예측에 한계가 있음을 확인하였다.

• Journal of Nutrition and Health
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• 제27권1호
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• pp.59-69
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• 1994

Dietary fiber(DF) intakes of Korean during 1969∼1990 were estimated and the major food sources of fiber were analyzed using the data from the Annual Reports of Korean National Nutrition Survey. The estimated daily DF intake of Korean has gradually decreased during the 22 years, from 24.46g in 1969 to 17.31g in 1990 with a remarkable decline in 1987. The average DF intakes of the rural population were higher than those fo urban's until 1980, but the situation was reversed until 1987 and the regional difference in DF consumption disappeared thereafter. Vegetables, cereals, grain and legumes were the major sources of fiber for Korean in recent 5 years(1986∼1990), providing 32%, 16% and 19% of DF intake respectively. Throughout the 22years, the intakes of DF from cereals and fresh vegetables have been reduced and those from processed vegetables, seaweeds and fruits has been increased. Df intake from legumes continuously increased until 1986, and it decreased thereafter. Rural population consumed more fiber from cereals than the urban's during the 1970s, but thereafter regional difference in cereal fiber intakes became insignificant. Urban population consumed more fiber from legumes and fruits than the rural's through the entire period. The results of this study indicate that the present DF intake of Korean is considerably lower than generally anticipated and is below the tentative recommended DF intake and thus higher DF intake than the present level is needed.

• 한국식품영양과학회지
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• 제26권3호
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• pp.540-548
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• 1997

According to the data published in 1990s on the intake of dietary fiber(DF) of Korean, DF intake of Korean has been gradually decreasing in the last two decades. Mean daily intake of DF in 1990s is estimated to be in the rage of 17-20g per capita and over seventy five percent of the subjects examined appeared to consume DF less than 20g per day. The major food sources of Df in Korean diet include cereals, vegetables, fruits, seaweeds and seasonings. The present level of DF intake of Korean is lower than the tentatively recommended minimum intake of DF. It is predicted that, if the present trend of change on food consumption pattern is maintained, the gradual increases in the incidence of chronic degenerative diseases will be continuing. Therefore, the beneficial effects of DF on health care and disease control should be emphasized through the nutritional education and high level consumption of DF needs to be strongly recommended in the dietary guideline. In order to raise the daily consumption of DF, more whole grain cereals need to be used as a part of staple and more frequent intake of legumes and seaweeds is required as well as the development of high-fiber diet recipes and natural high-fiber products.

• 한국축산식품학회지
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• 제31권2호
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• pp.273-279
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• 2011

전자코를 이용하여 아카시아 꿀, 잡화 꿀, 밤 꿀, 유채꿀, 사양 꿀, 목청 꿀, 기타 꿀을 대상으로 밀원에 따른 차이를 구분하였다. 그 결과 꿀 종류에 따라 뚜렷이 구분 가능하였으며 각기 다른 꿀을 혼합하였을 때 혼합 비율에 따라서도 구분 가능하였다. 0, 5, 10, 15, 20, 25, 30%의 사양 꿀을 목청 꿀에 혼합하였을 때 혼합비율이 증가함에 따라 41, 42, 43, 45, 46, 47, 48, 54, 56, 58, 60 amu의 감응도 값이 크게 나타났으며 판별함수분석한 결과 사양 꿀의 혼합비율이 증가함에 따라 DF1값이 양의 방향에서 음의 방향으로 일정한 경향을 보이며 뚜렷이 구분되었다(DF1: $r^2$=0.9962, F=490.6 DF2: $r^2$=0.9128, F=19.44). 이를 통하여 DF1값과 목청 꿀에 사양 꿀의 혼합 농도에 대해 DF1=-0.106$^*$(사양 꿀의 농도)+0.426($r^2$=0.96)와 같은 높은 상관관계식을 얻었다. 아카시아 꿀의 경우에도 목청 꿀과 유사하게 사양 꿀의 혼합비율이 증가함에 따라 41, 43, 45, 46, 47, 56, 57, 58, 59, 60, 61, 70 amu의 감응도 값이 크게 나타났으며 DF1과 사양 꿀 혼합 비율간에 높은 상관관계를 보이며 일정한 경향을 나타냈고(DF1: $r^2$=0.9957, F=396.64 DF2: $r^2$=0.9447, F=29.3) DF1=-0.112$^*$(사양 꿀의 농도)+0.434($r^2$=0.968)의 상관관계식을 갖는다.

• 대한한의학방제학회지
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• 제22권2호
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• pp.63-76
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• 2014

Objectives : This study investigated the improvement effects of Pakistani (DF-a) and Chinese Ephedra herba-containing Gangjihwan (DF-b) on obesity in a high fat diet-fed obese mouse model. Methods : Eight-week-old C57BL/6N mice were divided into four groups: a normal lean group given a standard diet, an obese control group given a high fat diet, and DF-a and DF-b groups given a high fat diet with DF-a (80 mg/kg), and DF-b (80 mg/kg), respectively. After 8 weeks of treatment, body weight gain, feeding efficiency ratio, blood lipid markers, fat weight and histology were examined. Results : 1. Body weight gain and fat mass were significantly decreased in DF-a and DF-b groups compared with control. The extent of decreases was eminent in DF-a group. 2. Feeding efficiency ratio and circulating leptin concentration were significantly decreased in DF-a and DF-b groups compared with control, whereas circulating adiponectin concentration was increased in DF-a and DF-b groups compared with control. 3. Consistent with their effects on body weight gain and fat mass, circulating concentrations of triglyceride, glucose and insulin were decreased in DF-a and DF-b groups compared with control. 4. The size of adipocytes were decreased by DF-a and DF-b compared with control, whereas the adipocyte number per unit area was increased by them, suggesting that DF-a and DF-b decreased the number of large adipocytes. 5. Consistent with their effects on body weight gain, liver fibrosis was reduced in DF-a and DF-b groups compared with control. Conclusions : In conclusion, these results suggest that DF-a and DF-b not only decrease feeding efficiency ratio, plasma leptin concentration, and blood anti-obesity biomarkers, but also reduce fat mass, contributing to the improvement of obesity. DF-a and DF-b also inhibit liver fibrosis. In addition, these effects were similar between Pakistani Ephedra herba and Chinese Ephedra herba-containing Gangjihwan.

• 한국통신학회논문지
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• 제21권7호
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• pp.1734-1745
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• 1996

본 논문에서는 디지탈 자기 기록 채널의 비선형 왜곡 보상을 위한 개선된 fixed-delay tree search with decision feedback(FDTS/DF)에 대하여 논한다. 고밀도로 갈수록 두드러지게 나타나는 비선형 왜곡은 일반적으로 이산 Volterra 급수로 잘 모델링되므로 비선형 feedforward 필터, 선형 궤환 필터, 그리고 비선형 왜곡 테이블에 의하여 등화기가 구성되며, 이 때 왜곡 테이블의 값은 미래의 기록 데이터에 의한 비선형 왜곡 영향을 고려하여 결성된다. FDTS를 사용한 결정단에서는 이전의 결정값, 현재의 추정치와 미래의 추정치를 고려하여 최소의 branch metric을 갖는 path가 선택된다. 모의 실험을 통하여 선형 FDTS/DF, 기존의 비선형 FDTS/DF, 그리고 제안된 비선형 FDTS/DF/DF의 성능이 비교되며, 제안된 비선형 FDTS/DF가 고밀도 기록시 가장 우수한 성능을 보임을 확인한다.

• 한국산학기술학회논문지
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• 제16권5호
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• pp.3434-3439
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• 2015

정보이론적 학습의 한 성능기준인 두 오차확률분포간 유클리드거리(MEDE)는 비선형 (결정 궤환, DF) 등화 알고리듬에 채택되었고 심각한 채널 왜곡과 충격성 잡음이 있는 환경에서 탁월한 성능을 보였다. 그러나 이 MEDE-DF 알고리듬은 과중한 계산 복잡성이라는 문제를 지니고 있다. 이 논문에서는 MEDE-DF 알고리듬을 위한 반복적 ED를 먼저 유도하고 그 다음 전후방 영역에 대해 가중치 기울기를 반복적으로 추정하는 식을 유도하였다. MEDE-DF 알고리듬의 반복적 기울기 추정방식의 효과를 입증하기위해 곱셈 계산량을 비교하였고 충격성 잡음과 수중 통신 환경에서 모의 실험한 MSE 성능 결과를 비교하였다. 제안한 DF 방식과 기존의 MEDE-DF 알고리듬의 곱셈 계산량 비는 샘플사이즈 N 에 대해 $2(9N+4):2(3N^2+3N)$로 나타나면서도 충격성 잡음과 수중통신 채널환경에서 동일한 MSE 학습 성능을 유지하였다.