• 한국산림과학회지
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• 제82권3호
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• pp.246-253
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• 1993

삼림토양(森林土壤)의 비옥도(肥沃度)를 질소성분(窒素成分)의 면에서 해명하기 위한 하나의 수단으로서 서로 다른 8개(個) 토양형(土壤型)에 대하여 질소(窒素)의 형태(形態)를 검토하였다. 유기물층(有機物層) 및 광질토양층(鑛質土壤層)의 무기능질소(無機態窒素)($NH_4-N+NO_3-N$)는 전질소(全窒素)에 대한 비율이 O층(層), 표층토(表層土) 및 하층토(下層土)에서 각각 약 2%, 3.7% 및 4.1% 이었다. O층(層)에 있어서의 유기능(有機能) 질소(窒素)의 형태(形態)는 분해(分解)가 진행됨에 따라 전반적으로 aminoacid-N의 감소와 amide-N 및 hexosamine-N의 증가(增加)경향이 있었다. 공시(供試)한 O층(層)의 각층위에 있어서 가수분해성질소(可水分解性窒素)는 약 80-90%로 수종간(樹種間) 또는 층위별간(層位別間)의 큰 차이는 없었다. L층(層)에 있어서는 aminoacid-N가 가장 많아 약 40-50%에 달했으며, 가수분해성질소(可水分解性窒素)의 반(半)이상을 점하였다. Amide-N은 적었으며 약 10-23% 이었다. 이들 유기능질소(有機態窒素)의 각(各) 획분조성(劃分助成)에 있어서 수종(樹種)에 따른 영향은 크게 나타나지 않았다. 환경인자(環境因子)의 영향(影響)을 가장 크게 반영하는 O층(層) 및 표층토(表層土)에 있어서 건성형(乾性型) 토양(土壤)과 습성형(濕性型) 토양(土壤)간의 명료한 차이는 없었다.

• 한국초지조사료학회지
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• 제18권3호
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• pp.243-250
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• 1998

This study was conducted to evaluate mineral content of Winter Rye, Nitrogen Balance, Soil chemical characteristics and NO,-N level in infiltration water as affected by different slurry application on the basis of N contents respectively and was arranged as a randomized complete block design with seven treatments (chemical fertilizer 160kg Nha, cattle slurry 160 . 320 - 480kg Nha, swine slurry 160 - 320 - 480kg Nha) and conducted at National Livestock Research Institute, RDA, in Suweon fiom Sep. 1996. to Apr. 1997. The results obtained are summarized as follows : Nirogen, Phosphorous, Calcium and Potassium of Winter Rye slightly increased as slurry application level was increased (p$NO_3$-N content ($\mu$g/g) of Winter Rye was shown fiom 780 to 1,462 in all treatments, especially , the swine slurry plots were significantly higher than that of cattle sluny plots (p < 0.05). As slurry application increased, show a marked trend toward surplus N input in all treatment. The pH of the topsoil (0~IOcm) was shown 6om 5.1 to 5.4 except the plot of chemical fertilizer before experiment pH of 5.1, but the pH of the subsoil (10~20cm) tended not to be regular. The content of available ,TEX>$P_2O_5$ inaeased with the increased application of slurry, particularly, the topsoil (O- 1Ocm) were much higher than the subsoil (10~20cm). The $NO_3$-N content of infiltration water (depth:lm) was increased as affected by sluny application.

• 운동영양학회지
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• 제23권2호
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• pp.16-21
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• 2019

[Purpose] The purpose of this study was to comparatively investigate the correlation among body composition, resting metabolic rate (RMR), and physical activity (PA) between young and middle-aged Korean adults. [Methods] A total of 53 [male n=23, female n=30] subjects were included in this study, among whom 34 subjects were healthy young adults [male n=18, female n=16] and 19 were middle-aged adults [male n=5, female n=14]. The body composition and RMR of all the participants were measured after overnight fasting (≥8 h). The Korean version of the WHO Global Physical Activity Questionnaire (GPAQ) was used to assess physical activity. [Results] Body composition was not significantly different between young adults and middle-aged adults. Whole-body bone mineral density and bone mineral contents (BMC) were significantly lower in middle-aged adults than in young adults. Total blood cholesterol (TC) and blood glucose levels were significantly higher in middle-aged adults (TC; 195.21 ± 43.34, glucose; 103.57 ± 12.61 mg/dL) than in young adults. RMR was significantly lower in middle-aged adults (1619.57 ± 290.28 kcal/day) than in young adults (1894.37 ± 405.00 kcal/day). In middle-aged adults physical activity (PA). PA (METs, min, EE) was inversely correlated with fat mass (FM, kg, and %) and blood triglyceride (TG) level in young adults. In middle-aged adults, PA showed a significant positive correlation with lean body mass (LBM), FM (%), and RMR. Furthermore, PA EE showed significant interrelatedness with BMC among middle-aged adults. [Conclusion] These results demonstrated that high PA levels enable LBM and RMR maintenance in middle-aged adults. Furthermore, in young adults, more PA is required to induce change in body composition.

• 한국초지조사료학회지
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• 제19권3호
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• pp.203-210
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• 1999

가축액비의 영양성분 중 질소(N)는 환경적인 면과 사초수량을 고려했을 때 잠재력이 가장 높다. 본 연구는 추파용 연맥에 가축액비의 N 함량을 기준으로 시용수준을 달리하여 시용했을 때 추파용 연맥(Avena saliva L.)의 무기물 함량 및 질산태질소 함량 그리고 토양화학성분 변화를 구명하고자 7처리(화학비료표준구 $120kg\;N\;ha^{-1}$, 우분액비구 120, 240, $360kg\;N\;ha^{-1}$ 돈분액비구 120, 240, $360kg\;N\;ha^{-1}$)를 난괴법 3반복으로 배치하여 1997년 수원에서 수행하였다. 대조구와 비교하여 추파용 연맥의 무기물 함량은 액상분뇨의 시용량이 증가됨에 따라 증가되는 경향을 보였다. 추파용 연맥의 질산태질소 함량은 $1,881-2,605mg\;kg^{-1}$의 범위를 보였으며, 금비구>우분액비 $360kg\;N\;ha^{-1}$구>돈분액비 $240kg\;N\;ha^{-1}$구 순이었다. 액상분뇨의 시용량이 증가될 수록 토양중 치환성 양이온 함량이 높아지는 경향을 보였다. 토양중 전질소 및 무기태질소량은 액상분뇨 시용량에 따라 달랐는데 그 중에서도 돈분액비 $360kg\;N\;ha^{-1}$ 구에서 가장 높았다. 토양침투수중 질산태질소 농도는 시험기간중 심한 변이를 나타내지 않았다. 이상의 결과로 볼 때 토양중 질소량은 돈분액비 $360kg\;N\;ha^{-1}$구, 돈분액비 $240kg\;N\;ha^{-1}$ 순이었다.

• 한국토양비료학회지
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• 제30권4호
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• pp.309-313
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• 1997

벼 건답직파 재배시 볏짚 시용과 질소 분시에 따른 벼 질소 흡수 양상을 검토하고자 호남평야지인 전북통에서 동진벼를 공시하여 포장 시험한 결과를 요약하면 다음과 같다. 1. 건답기간중 토양질소의 변화 양상을 보면 요소태질소는 파종후 7일이후에는 검출되지 않았으나, $NH_4-N$는 파종후 7일, $NO_3-N$는 파종후 25일에 최대값을 나타냈다. 2. 토양 깊이 70cm에서 채취된 토양 용액중 $NO_3-N$의 농도는 질소분시가 적은 기비중점인 구에서 파종후 생육초기에 감소되는 양이 많았으며, 볏짚을 처리함 으로써 표토로부터 심토로 이동되는 양을 감소시킬수 있었다. 3. 수확기 질소흡수량은 볏짚시용시 질소3회 분시구에서 가장 많았으며, 시비질소에 의한 질소이용률은 20%였으나, 볏짚 시용으로 27%까지 향상 시킬수 있었다. 4. 질소 분시에 따른 수량은 관행 5070 kg/ha, 질소 전량 기비구 4970 kg/ha, 2회 분시구 5110 kg/ha, 3회 분시구 5150 kg/ha로 관행에 비하여 근소한 차이로 증가 되었다.

• 한국노년학
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• 제31권2호
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• pp.303-315
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• 2011

본 연구의 목적은 12주간 저항성훈련에 따른 노화 흰쥐의 골밀도 및 골대사 관련 지표에 미치는 영향을 관찰하는 것이다. 생후 64 주령의 Sprague-Dawley계 노화 흰쥐(체중 565±3.12)를 대조군(n=10)과 저항성 훈련군(부하 없는 저항성 훈련군(n=10)과 부하 있는 저항성 훈련군(n=10)으로 분류하여 주 4회 12주간 사다리 오르기 훈련을 실시한 후 골밀도 및 골대사 관련 지표의 변화를 측정한 결과 다음과 같은 결론을 얻었다. 대퇴골의 회분 및 칼슘 햠량은 부하 있는 저항성 훈련군>부하 없는 저항성 훈련군>대조군 순으로 유의하게 증가하였으며, 세 집단간 유의한 차이가 나타났다. 인지질 함량은 부하 있는 저항성 훈련군>부하 없는 저항성 훈련군, 부하 있는 저항성 훈련군>대조군 순서로 나타났는데, 대조군에 비교하여 부하 있는 저항성 훈련군에서만 유의한 차이가 나타났다. 골강도와 osteocalcin 농도는 부하 있는 저항성 훈련군>부하 없는 저항성 훈련군>대조군 순으로 유의하게 증가하였으며, 세 집단간 유의한 차이가 나타났다. 본 연구를 종합하면 노화 흰쥐에서 12주간 저항성훈련은 대퇴골밀도와 골대사관련 지표에 유익한 효과를 나타내는데 이러한 결과는 저항성훈련으로 인한 골밀도의 증가는 골재흡수의 지표인 osteocalcin 과 골의 기계적구조의 변화뿐만 아니라 훈련의 강도(training intensity)가 중요한 매개 요인임을 알 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권11호
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• pp.1597-1602
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• 2006

The effects of different mineral supplementations on the milk yield of free-ranging Somali camels were investigated in two phases in a semi-arid region of northern Kenya during the dry and wet seasons in 2002 and 2003. In phase 1, twelve (12) lactating camels were selected at random to form four (4) groups each consisting of three camels. The first group served as the control and as a result received no mineral supplementation. In addition to the control diet the other groups received oral doses of minerals as follows over a 60-day period: T1 (P), T2 (High Cu low Co) and T3 (Low Cu high Co). The daily milk yield and blood mineral profiles were measured during the wet and dry seasons. The mean daily milk yield increased from 3.4 L/d to $4.3{\pm}0.3L/d$ and 5.2 L/d in the dry and wet seasons, respectively. Fifteen (15) lactating camels were selected at random to form five groups each consisting of three replicates. The control group did not receive any mineral supplement. The other four groups in addition to the control diet, received the following treatments: T4 (Common Salt), T5 (High Co), T6 (High Co+P) and T7 (Low Co+P). Mineral supplement T6 produced significantly higher milk yield ($5.4{\pm}0.5$ and $6.5{\pm}0.7L/d$) during the dry and wet seasons. Both T6 and T7 had significantly higher milk yield than T4 and T5. During both phases, the blood Ca and P level significantly increased in camels receiving T1, 6 and 7. Animals that received only the trace mineral supplements had lower blood P compared to the ones receiving supplementary P and also the control. Supplementation of lactating camels with Co and P significantly (p<0.05) increased milk yield). Effect of common salt, commonly given by farmers, on milk yield was insignificant. It was concluded that mineral supplementation to lactating camels was beneficial, and that mineral supplements should include P and Co. Further research is required to establish P and Co requirements of lactating camels.

• Journal of Ginseng Research
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• 제44권6호
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• pp.823-832
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• 2020

Background: The formation of a nanotube layer on a titanium nanotube (N-Ti) plate facilitates an active reaction between bone cells and the material surface via efficient delivery of the surface materials of the dental implant into the tissues. Studies have reported that Korean Red Ginseng extracts (KRGEs) are involved in a variety of pharmacological activities: we investigated whether implantation with a KRGE-loaded N-Ti miniimplant affects osteogenesis and osseointegration. Methods: KRGE-loaded nanotubes were constructed by fabrication on pure Ti via anodization, and MC3T3-E1 cells were cultured on the N-Ti. N-Ti implants were subsequently placed on a rat's edentulous mandibular site. New bone formation and bone mineral density were measured to analyze osteogenesis and osseointegration. Results: KRGE-loaded N-Ti significantly increased the proliferation and differentiation of MC3T3-E1 cells compared with cells on pure Ti without any KRGE loading. After 1-4 weeks, the periimplant tissue in the edentulous mandibular of the healed rat showed a remarkable increase in new bone formation and bone mineral density. In addition, high levels of the bone morphogenesis protein-2 and bone morphogenesis protein-7, besides collagen, were expressed in the periimplant tissues. Conclusion: Our findings suggest that KRGE-induced osteogenesis and osseointegration around the miniimplant may facilitate the clinical application of dental implants.

• Geomechanics and Engineering
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• 제37권6호
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• pp.577-590
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• 2024

With increasing demand for nuclear power generation, nuclear structures are being planned and constructed worldwide. A grave safety concern is that these structures are sensitive to large-magnitude shaking, e.g., during earthquakes. Seismic response analysis, which requires P- and S-wave velocities, is a key element in nuclear structure design. Accordingly, it is important to determine the P- and S-wave velocities in the Gyeongju and Pohang regions of South Korea, which are home to nuclear power plants and have a history of seismic activity. P- and S-wave velocities can be obtained indirectly through a correlation with physical properties (e.g., N values, Young's modulus, and uniaxial compressive strength), and researchers worldwide have proposed regression equations. However, the Gyeongju and Pohang regions of Korea have not been considered in previous studies. Therefore, a database was constructed for these regions. The database includes physical properties such as N values and P- and S-wave velocities of the soil layer, as well as the uniaxial compressive strength, Young's modulus, and P- and S-wave velocities of the bedrock layer. Using the constructed database, the geological characteristics and distribution of physical properties of the study region were analyzed. Furthermore, models for predicting P- and S-wave velocities were developed for soil and bedrock layers in the Gyeongju and Pohang regions. In particular, the model for predicting the S-wave velocity for the soil layers was compared with models from previous studies, and the results indicated its effectiveness in predicting the S-wave velocity for the soil layers in the Gyeongju and Pohang regions using the N values. The proposed models for predicting P- and S-wave velocities will contribute to predicting the damage caused by earthquakes.

• Ocean and Polar Research
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• 제36권4호
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• pp.423-435
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• 2014

Verifying the similarity of environmental characteristics between an artificial impact site and a preserved or reference site is necessary to quantitatively and qualitatively evaluate the environmental impact of mining activity. Although an impact site (BIS station) and a preserved site (called KOMO station) that have been selected in the Korea manganese nodule contract area may share similar environmental characteristics, similarities in terms of the water column environment between both sites has not been investigated. In this study, we compared the chemical properties of the water columns and sinking particle fluxes between BIS and KOMO stations through two observations (August 2011 and September 2012). Additionally, we observed particle fluxes at the KOMO station for five years (July 2003~July 2008) to understand long-term natural variability. Vertical distributions of water column properties such as dissolved oxygen, inorganic nutrients (N, P, Si), total organic carbon below surface layer (within the depth range of 200 m) were not considerably different between the two sites. Especially, values of water column parameters in the abyssopelagic zone from 4000 m to bottom layer (~5000 m) were very similar between the BIS and KOMO sites. Sinking particle fluxes from the two sites also showed similar seasonality. However, natural variation of particle flux at the KOMO site varied from 3.5 to $129.9mg\;m^{-2}day^{-1}$, with a distinct temporal variation originating from ENSO events (almost forty times higher than a minimum value). These results could provide valuable information to more exactly evaluate the environmental impact of mining activity on water columns.