• Journal of the Korean Wood Science and Technology
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• 제42권5호
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• pp.523-532
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• 2014

This study was done to evaluate the antioxidant effect of oak hot water extracts on the oxidative stress induced by reactive oxygen species (ROS). The cytotoxicity of $H_2O_2$-induced oxidative stress was performed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay for the cell viability according to the dose-dependent treatment. Oak extracts demonstrated a dose-dependent ability to inhibit $H_2O_2$-induced apoptosis in cultured tenofibroblasts, as assessed by MTT assay and FACS analysis. $H_2O_2$ increased the phosphorylation of extracellular regulated kinase1/2 (ERK1/2) and of c-Jun N-terminal kinase (JNK) and the production of reactive oxygen species (ROS). In contrast, treatment with oak extracts was decreased this activation of ERK1/2 and JNK, as confirmed by western blot analysis, and reduced the production of ROS, as verified by fluorescent microscopic and flow cytometry (FACS) analyses. These findings suggest that oak extracts, by suppressing JNK, ERK1/2, and intracellular ROS production, have a concentration-dependent antiapoptotic effect on achilles tenofibroblasts exposed to an oxidative stressor, and may have therapeutic potential.

• 한국생태학회:학술대회논문집
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• 한국생태학회 2002년도 VIII 세계생태학대회
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• pp.101-105
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• 2002

Fine root decomposition and nutrient release patterns were examined using in situ buried fine root (< 2mm in diameter) bags inserted vertically into the mineral soil to a depth of the top 15 cm in a sawtooth oak (Quercus acutissima) and a Korean pine (Pinus korainesis) stands in the Jungbu Forest Experiment Station, Kyonggi-do, Korea. The pine roots compared with the oak roots showed rapid mass loss in early stages of decomposition, but decomposed similarly after 12 months of incubation. Decomposition rates of fine roots were about 33%/yr for the oak roots and 37%/yr for the pine roots. Nutrients except for calcium and phosphorus showed similar concentrations between the oak and the pine roots during the study period. However, calcium concentration was significantly higher in the oak than in the pine roots. Nutrient concentrations in both stands except for nitrogen decreased during the study period. In addition, potassium compared with other nutrients was the most mobile ion and about 70% of initial amount was released during the first 3 months of incubation. The results indicate that tree species influence mass loss and nutrient dynamics of fine roots on similar site conditions.

• The Korean Journal of Ecology
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• 제25권4호
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• pp.235-239
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• 2002

Fine root decomposition and nutrient release patterns were examined using in situ buried fine root (＜ 2mm in diameter) bags inserted vertically into the mineral soil to a depth of the top 15 cm in a sawtooth oak (Quercus acutissima) and a Korean pine (Pinus korainesis) stands in the Jungbu Forest Experiment Station, Kyonggi-do, Korea. The pine roots compared with the oak roots showed rapid mass loss in early stages of decomposition, but decomposed similarly after 12 months of incubation. Decomposition rates of fine roots were about 33%/yr for the oak roots and 37$\%$/yr for the pine roots. Nutrients except for calcium and phosphorus showed similar concentrations between the oak and the pine roots during the study period. However, calcium concentration was significantly higher in the oak than in the pine roots. Nutrient concentrations in both stands except for nitrogen decreased during the study period. In addition, potassium compared with other nutrients was the most mobile ion and about 70$\%$ of initial amount was released during the first 3 months of incubation. The results indicate that tree species influence mass loss and nutrient dynamics of fine roots on similar site conditions.

• Journal of Ecology and Environment
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• 제32권4호
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• pp.237-247
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• 2009

This study was conducted to determine the carbon (C) contents in different mixed stands of P. dens if/ora and deciduous oak species in Gwangneung, central Korea. Five mixed stands with different ratios of P. densiflora and deciduous oak species were chosen based on the basal area of all trees ${\geq}\;5cm$ DBH: pure P. densiflora (P100D0), 70% P. densiflora + 30% deciduous oak species (P70D30), 44% P. densiflora + 56% deciduous oak species (P50D50), 37% P. densiflora + 63% deciduous oak species (P40D60), and 10% P. densiflora + 90% deciduous oak species (P10D90). Total C contents in the overstory (aboveground and belowground) vegetation were higher in the mixed stands (P70D30, P50D50, P40D60) than in the pure stands (P100D0, P10D90). Moreover, except for P40D60, C contents of forest floor (litter and coarse woody debris) were larger in the mixed stands (P70D30, P50D50) than in the pure stands. However, total soil C contents up to 30cm depth were highest in the pure deciduous oak stand than in the pure P. densiflora stand and mixed stands. Total ecosystem C contents (Mg/ha) were 163.3 for P100D0, 152.3 for P70D30, 188.8 for P50D50, 160.2 for P40D60, and 150.4 for P10D90, respectively. These differences in total ecosystem C contents among the different mixed stands for P. densiflora and deciduous oak species within the study stands were attributed by the differences in vegetation development and forest management practices. Among the five study stands, the total ecosystem C contents were maximized in the 1:1 mixed ratio of P. densiflora and deciduous oak species (P50D50).

• 한국산림과학회지
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• 제88권4호
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• pp.533-540
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• 1999

표고 재배용 참나무류 중에서 굴참나무는 수피가 두꺼워서 참나무의 내수피 (2차 사부조직)에 알을 낳는 털두꺼비하늘소(Moechotypa diphysis)의 산란을 어렵게 하였다. 굴참나무의 수피 두께는 평균 7.4 mm로서 다른 참나무 수종(신갈은 평균 1.1mm, 졸참은 1.3mm, 상수리는 2.0mm) 보다 3-7배나 두꺼웠다. 내수피의 두께는 상수리가 4.8mm로 가장 두껍고 다른 수종은 3.6-3.9mm 였다. 털두꺼비하늘소가 원목의 수피에 뚫은 산란공의 외부형태는 굴참나무에서 $8-12mm{\times}6-8mm$ 크기의 넓은 타원형이었으며, 다른 3수종에서는 $5-9mm{\times}1-5mm$로 좁은 타원형이었다. 털두꺼비하늘소는 굴참나무 조사목 중 9%의 원목(1.2m 길이)에 원목당 평균 3개의 산란공을 뚫었으며, 실제로 산란공에 알이 있는 비율은 15%였다. 반면에 이 하늘소가 선호하여 산란하는 수종은 신갈나무로서 조사된 원목 32개의 전부에 산란공을 뚫었으며, 원목당 산란공 수는 평균 20개, 그 산란공에 알이 있는 빈도는 56%였고, 이 중에서 35%가 6월초에 이미 부화하여 유충이 내수피를 가해하고 있었다. 털두꺼비하늘소가 산란하는데 선호하는 참나무 수종은 수피가 매끈하고 표피가 잘 벗겨지지 않는 얇은 것으로 생각된다.

• Journal of the Korean Wood Science and Technology
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• 제42권6호
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• pp.691-699
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• 2014

용융점이 $138^{\circ}C$인 Bi-Sn 혼합합금 주입방법을 이용한 용융합금주입목재복합체의 제조를 통해 목재의 단점인 치수 안정성과 내구성의 개선을 하고자 3가지 주요 침 활엽수 수종의 수종별 최적주입조건을 구명하고, 주입에 따른 금속주입목재복합체의 중량증가율, 열전도도, 전기저항 등의 물리적 성질과 기계적 성질을 실험하여 다음과 같은 결과를 얻었다. 1. 금속주입목재의 최적처리 조건은 $185^{\circ}C$, 진공시간 10분 조건하에서 radiata pine의 경우 $10kgf/cm^2$ 가압시간 2분 30초, red oak는 $30kgf/cm^2$, 가압시간 10분, white oak는 $50kgf/cm^2$, 가압시간 10분에서 최적의 주입조건을 나타냈다. 2. 금속주입목재복합체의 외관적 특징은 전체적으로 재색은 회백색을 나타냈으며, 목재의 무늬를 그대로 유지하고 있다. 3. 침엽수 수종인 radiata pine은 저온용융합금주입처리로 인해 중량증가율은 12배, 밀도는 $6.13g/cm^3$으로 15배나 증가하였으나, 인테리어용으로 주로 사용되는 red oak와 white oak 등의 활엽수의 경우 목재해부학적 특성으로 의해 radiata pine보다는 낮은 5~6배의 밀도증가율을 나타냈다. 4. 주입된 목재는 침 활엽수 모두 금속주입으로 인해 수분흡수율과 두께팽윤율이 현저히 감소하였고, 매우 높은 치수 안정성을 나타냈으며, 금속주입목재복합체의 휨강도, 휨영계수, 경도 및 전기전도도와 열전도도 등도 무처리목재보다 매우 크게 향상되었다.

• 한국식품저장유통학회지
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• 제18권6호
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• pp.891-897
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• 2011

일반적으로 적포도주는 장기간, 백포도주는 단기간 동안 발효가 끝난 뒤에 오크통에서 숙성 과정을 거치게 된다. 최근에는 오크통을 대신할 목적으로 포도주에 오크칩을 첨가하여 숙성하기도 한다. 본 연구에서는 다양한 시간별로 열처리한 국산 참나무편을 적포도주에 넣은 다음 숙성에 따른 변화를 비교해 봄으로써 색의 안정성과 풍미 개선에 도움을 줄 수 있는 적절한 전처리 조건을 알아보고자 하였다. 참나무편의 첨가 유무에 따른 알코올과 당도 및 총산 함량의 변화는 없었지만 pH의 경우는 참나무편 처리구에서 높게 나타났다. 총페놀 화합물의 함량은 참나무편 처리구에서 0.15-0.19%으로서 무처리구인 0.10%에 비하여 높은 값을 나타내었으나 레스베라트롤과 카테킨의 경우는 그 함량이 각각 3.88-5.05 ppm, 40.60-41.98 ppm으로 참나무 편의 첨가 또는 열처리 시간에 따른 유의적인 차이가 나타나지 않았다. 아세트알데히드의 함량은 참나무편 처리 유무에 영향이 없으나 메탄올, 에틸아세테이트 및 퓨젤유의 함량은 참나무편의 처리구에서 높게 나타났다. 참나무편의 열처리 시간이 길어질수록 intensity 값은 증가하였으며 또한 L, a, b 값의 감소량이 적은 것으로 보아 참나무편의 첨가가 포도주의 색 안정화에 기여함을 알 수 있었다. 관능 평가를 실시한 결과 색에서 참나무편을 첨가하지 않은 포도주가 가장 높은 점수를 받았으나 2시간 열처리한 참나무편을 처리한 포도주가 향과 맛, 전반적인 기호도에서 가장 높은 점수를 받았다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권6호
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• pp.843-848
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• 2009

This experiment was conducted to compare the effects of oak acorns and corn on broilers growth performance, carcass characteristics and meat fatty acid (FA) composition according to different ages of broilers. Two separate groups of 400 male broilers, reared for six weeks, were fed diets containing 33.5% green oak acorns (GO) and 67% of corn (C), respectively. At day 35, the body weight of the chickens fed the GO diet was 12% lower (p<0.05) compared with controls (C). However, at day 56 birds reached similar final weights. Abdominal adipose tissue (AAT) was 78% higher in the controls compared to those fed the oak acorn-based diet. The total lipids (TL) of thigh muscle were higher in the controls compared to dietary treatment GO (3.1 against 2.5 g/100 g of muscle). There were significant differences in fatty acid (FA) composition of the muscle between two groups. The broilers fed oak acorn exhibited more C18:2, as well as a higher proportion of polyunsaturated fatty acid (PUFA) and PUFA:SFA (saturated fatty acid) ratio than those on the control diet, but no significant differences were observed among groups for the age of birds. There was a higher proportion of linolenic acid in broilers fed the oak acorn compared to the controls (0.8 vs. 0.6%). Furthermore, linolenic acid content decreased with age (p<0.001) in both groups. The results indicated no significant differences in FA with the age of birds. In conclusion, the meat fatty acids provided by the GO diet appeared to improve the nutritional quality preferred by the consumer.

• 한국축산시설환경학회지
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• 제14권2호
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• pp.91-96
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• 2008

The odours from spreading the slurry, manure storage tanks, and the stall are a source of annoyance for the neighbors and sometimes even become a case for civil appeal. Reducing the odourant and ammonia emission is an urgent need to be addressed. It is known that brown coal and oak charcoal have an ability to absorb odour. We designed an experiment set in lab scale and used the brown coal and oak charcoal as additives in the test to reduce odour. The test are divided into two categories; namely aeration and no-aeration. The additives were added to the each sample at a concentration of 5% and 10% of total base solids, besides the control samples. We carried out the Phenate Method for ammonia analyzing. In the non-aerated case, the results showed a reducing efficiency of 23.7% and 26.4% with an addition rate of 5% and 10% of additives, respectively. In the aerated test, the reducing efficiency of ammonia was 17.8% and 21.0% with an addition rate of 5% and 10% of additives, respectively. In case of oak charcoal, non-aeration showed removal efficiencies of ammonia at 15.9% and 16.1% with addition rates of 5% and 10%, respectively, With aeration, they were 11.4% and 26.4% with addition rates of 5% and 10% oak charcoal, respectively. The tests show that brown coal and oak charcoal have a reducing effect on ammonia emissions.

• 한국잠사곤충학회지
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• 제36권2호
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• pp.130-137
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• 1994

천잠의 사육환경을 구명하기 위하여 사료자원, 기상환경 및 사육방법등에 관하여 조사한 결과를 다음과 같이 요약한다. 1. 천잠의 실내사육에 있어 사육온도는 항온보다 변온이 좋은 편이며, 치잠기 25~26$^{\circ}C$, 장잠기 22~23$^{\circ}C$ 범위가, 사육습도는 치잠기 80~90%, 장잠기 60~70% 범위가 적당한 것으로 나타났다. 2. 천잠사육에 있어 광조기는 유충의 성장에 미치는 영향이 크지 아니하였다. 3. 귀잠시기는 빠른것이 늦은 것보다 유충시기에 단축되는 경향이 있으며 질도 양호한 것으로 나타났다. 4. 사료수종은 상수리나무가 밤나무보다 더 적합한 것으로 나타났다. 야생수보다 재배수가 사육성육이 더 좋았다. 5. 천잠을 옥외사육으로 전환하는 시기는 빠를수럭 작황이 불안정해 지는 경향을 보였다.