• Asian-Australasian Journal of Animal Sciences
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• 제22권4호
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• pp.520-527
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• 2009

Alfalfa (Medicago sativa L) is a high-quality forage for ruminants and the main stem is the dominant morphological component contributing to the forage nutritive value in mature alfalfa forage. Shearing force, a fracturing property of plant stem, is an important indictor of forage value. The objectives of this study were to investigate the effects of morphological characteristic on shearing force, the relationship between shearing force and chemical composition, and the relationship between shearing force and in situ digestibility of alfalfa stem. The results showed that linear density (weight per unit length of stem) was more important than chemical composition in affecting shearing force. There was a positive relationship between lignin content and shearing force (r = 0.78). Correlations were not found between shearing force and other chemical components such as neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose and hemicelluloses. In situ digestibility (of dry matter and NDF) was related to shearing force. A negative correlation was found between shearing force and dry matter (DM) digestibility (r = -0.70), and there was also a negative correlation between shearing force and NDF digestibility (r = -0.87). When shearing force was standardized for stem diameter or stem linear density, the relationship between shearing force and digestibility was consistent regardless of stem diameter and stem linear density. Shearing force was significantly correlated with lignin content and in situ digestibility (of DM and NDF), and was a more direct indicator for estimating forage nutritive value related to animal performance, so it can be used to predict the forage value of alfalfa.

• Asian-Australasian Journal of Animal Sciences
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• 제30권12호
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• pp.1718-1723
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• 2017

Objective: The study explored the dynamics of shearing force and its correlation with chemical compositions and in vitro dry matter digestibility (IVDMD) of stylo. Methods: The shearing force, diameter, linear density, chemical composition, and IVDMD of different height stylo stem were investigated. Linear regression analysis was done to determine the relationships between the shearing force and cut height, diameter, chemical composition, or IVDMD. Results: The results showed that shearing force of stylo stem increased with plant height increasing and the crude protein (CP) content and IVDMD decreased but fiber content increased over time, resulting in decreased forage value. In addition, tall stem had greater shearing force than short stem. Moreover, shearing force is positively correlated with stem diameter, linear density and fiber fraction, but negatively correlated with CP content and IVDMD. Conclusion: Overall, shearing force is an indicator more direct, easier and faster to measure than chemical composition and digestibility for evaluation of forage nutritive value related to animal performance. Therefore, it can be used to evaluate the nutritive value of stylo.

• The Korean Journal of Ecology
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• 제27권1호
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• pp.27-33
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• 2004

Cryptomeria japonica plantation was monitored every year during 15 years from 1983 to 1997 for stem diameter and volume. The reciprocal equation, 1/Y = A + B/N, was applied to the relationship between cumulative volume Y and cumulative number N from the largest tree in the stand each year. The parameters A and B, which means respectively the reciprocal of an asymptotic value of total stand stem volume and the reciprocal of the maximum stem volume, are related by a power function. The power functional relationship between A and B derived a linear relationship of B-points ( $N_{B}$, $V_{B}$; $N_{B}$ = B/A, $Y_{B}$ = 1/2A) of each Y-N curve on log-log coordinates. The gradient of B-point line was so steep that the Y-N curve moved parallel upward year by year. The time trajectory of mean stem volume (W) and density ($\rho$) provided evidence in favor of the 3/2 power law of self-thinning, because the gradient of W - $\rho$ trajectory on log-log coordinates approximated to -3/2 at the final stage of stand development. On the basis of the results of Y-N curves and W - $\rho$ trajectory, the time trajectory of maximum stem volume $W_{max obs}$ and $\rho$ was derived theoretically. The gradient of $W_{max obs}$ - $\rho$ trajectory on log-log coordinates is calculated to be -0.6105 at the final stage. The gradient of $W_{max obs}$ - $\rho$ trajectory was steeper than that of W - $\rho$ trajectory at the early stage, while the former is gentler than the latter at the later stage.stage.e.age.e.

• 농업과학연구
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• 제12권2호
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• pp.183-190
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• 1985

식물생장억제제(植物生長抑制劑)인 Paclobutrazol이 수도(水稻)의 도복(倒伏)에 미치는 제형질(諸形質)과 수량(收量)에 미치는 영향(影響)을 조사(調査)하고자 낙동벼와 섬진벼를 공시하여 질소(窒素) 12,20kg/10a을 이용(利用)한 조건(條件)에서 Paclobutrazol 12,18g ai/10a을 출수전(出穗前) 20,15,10 일에 토양처리(土壤處理)하였다. 1. Paclobutrazol 18g ai/10a을 출수전(出穗前) 20일과 15일에 처리(處理)하면 수도(水稻)의 간장(稈長)은 전반적(全般的)으로 짧아졌으며, 특히 제(第) 3 절간(節間)에서 그 경향(傾向)이 현저하였다. 간장(稈長)은 Paclobutrazol 12,18g ai/10a을 출수전(出穗前) 20, 15일에 처리(處理)할 때 낙동벼에서 다소 짧아진 경향(傾向)이었다. 2. Paclobutrezol 처리(處理)에 의하여 간단면적(稈斷面積), linear density 및 줄기의 휨 강도 (EI)는 증가(增加)되었고 줄기가 만곡(彎曲)되는 경향(傾向)은 적었다. 3. 휨강도와 간단면적(稈斷面積), 간단축직경(稈短軸直徑) 및 linear density는 정(正)의 상관(相關), 줄기의 만곡각도(彎曲角度)와 간단면적(稈斷面積) 및 간단축직경(稈短軸直徑)과는 부(負)의 상관관계(相關關係)가 있었다. 4. Paclobutrazol 12g ai/10a 을 출수전(出穗前) 10, 15일에 처리(處理)하면 수량(收量)은 감소(減少)되지 않았으나 Paclobutrazol 18g ai/10a을 출수전(出穗前) 20일에 처리(處理)하면 수량(收量)은 약간 감소(減少)되는 경향(傾向)이었다.

• 한국산림과학회지
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• 제98권5호
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• pp.576-583
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• 2009

Based on the stem analysis and biomass measurement of 36 trees and 1,576 branches in Pinus sylvestris var. mongolica (Mongolian pine) plantations of Northeast China, this study was conducted to develop estimation model equation for leaf biomass of a single tree and branch, to examine the vertical distribution of leaf biomass in the crown, and to evaluate the proportional ratios of biomass by tree parts, stem, branch, and leaf. The results indicated that DBH and crown length were quite appropriate to estimate leaf biomass. The biomass of single branch was highly correlated with branch collar diameter and relative height of branch in the crown, but not much with stand density, site quality, and tree height. Weibull distribution function would have been appropriate to express vertical distribution of leaf biomass. The shape parameters from 29 sample trees out of 36 were less than 3.6, indicating that vertical distribution of leaf biomass in the crown was displayed by bell-shaped curve, a little inclined toward positive side. Apparent correlationship was obtained between leaf biomass and branch biomass having resulted in linear function equation. The stem biomass occupied around 80% and branch and leaf made up about 20% of total biomass in a single tree. As the level of tree class was increased from class I to class V, the proportion of the stem biomass to total biomass was gradually increased, but that of branch and leaf became decreased.

• 한국작물학회지
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• 제38권3호
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• pp.240-244
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• 1993

야콘의 재배기술의 확립을 위하여 멀칭효과 및 재식밀도 실험을 한 결과는 다음과 같다. 1. 지상부 생육은 7월 중순부터 직선적으로 증가하였으며, 밀칭구나 비멀칭구에서 재식밀도가 높을수록 초장의 생육이 양호하였고, 특히 70 ${\times}$ 55cm에서 가장 좋았다. 2. 측지수는 정식 후 3개월부터 발생하였으며, 멀칭 및 재식밀도에 따라 유의한 차이를 나타내지 않았다. 3. 야콘괴경의 생체수량은 멀칭구가 비멀칭구 보다 높았으며, 멀칭구에서는 70${\times}$40cm구가 3561.7kg으로 가장 높았다. 4. 괴근수는 멀칭구에서 밀식할수록 많았으며, 근경과 근장에서는 유의적인 차이가 없었다.

• 한국식품조리과학회지
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• 제32권6호
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• pp.665-676
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• 2016

Purpose: This study was conducted to find the optimal freezing method and storage conditions for welsh onion. Methods: Cut welsh onions (0.3 cm) were packed in nylon/linear low density polyethylene (LLDPE) film bags, and frozen utilizing still-air freezing at -$20^{\circ}C$ (SAF20) and -$40^{\circ}C$ (SAF40), and immersed-liquid freezing at -$40^{\circ}C$ (ILF40); they were then stored at -$20^{\circ}C$ for 7 months. During storage, quality characteristics were measured monthly. Results: Drip loss was the lowest in the ILF40 packaging. Color difference in the stem (white part) did not differ significantly according to freezing conditions and storage time. Color difference in the leaf (green part) and stem was the lowest in SAF20. pH remained unchanged, while total aerobic bacterial count, pyruvic acid and moisture content decreased during storage. Pyruvic acid content of ILF40 was the highest among the freezing treatments. Fructose and glucose contents increased gradually during storage. Citric acid, malic acid, succinic acid and fumaric acid contents were unaffected, regardless of the freezing conditions. Conclusion: The optimal freezing method for welsh onions with the least quality changes was determined to be immersed liquid freezing, following by preservation up to 7 months by freeze-storing.

• Asian-Australasian Journal of Animal Sciences
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• 제26권10호
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• pp.1466-1473
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• 2013

This experiment was conducted to study the variation laws and correlations of shearing force and feed characteristics including morphological characteristic, chemical composition and in situ degradability of wheat straw. Feasibility of evaluating the nutritional value of wheat straws with shearing force values was analyzed in this study. Six hundred wheat straw plants (Jimai 22) were randomly selected and placed in a cool and ventilated place. Samples were collected in the 1st, 15th, 30th, 45th, 60th d after harvest to measure shearing force, morphological characteristic, nutritional composition. Rumen degradation of dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of wheat straws were determined by the nylon bags method. The results demonstrated that linear and quadratic effects of storage time on all the tested morphological characteristics were significantly correlative (p<0.01). As storage time goes on, all the tested nutrients and their rumen degradations of wheat straw was linearly (p<0.01) and quadratic (p<0.01) correlative except ADF content and rumen degradation of ADF. Significant correlations were determined in linear effect of shearing force on morphological characteristics (p<0.01), and linear density and diameter were a more sensitive predictor than stem thickness for shearing force. There were strong correlations between storage time and all the measured physical characteristics (shearing force, morphological characteristics and shearing force standardized by morphological characteristics) (p<0.01). Nutrition compositions were linearly correlative with shearing force and standardized shearing force (p<0.01). The linear correlation between rumen degradation of DM and NDF and shearing force and standardized shearing force were evident (p<0.01). In conclusion, shearing force, nutrition compositions and their rumen degradation of wheat straw were still dynamic with storage time after harvest. Correlation could be found between shearing force and nutritional characteristics of wheat straw. Nutrient content, morphological index and rumen degradation of DM and NDF could be predicted by changes in shearing force. Shearing force should be applied according to a standardized storage time when it is used to forecast the feed value of wheat straws.

• Composites Research
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• 제12권4호
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• pp.71-78
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• 1999

방향족 아민 경화제의 벤젠링 사이의 관능기 변화가 반응특성, 기계적특성 및 열적특성에 미치는 영향을 고찰하기 위하여 양쪽 말단기에 에폭시기를 가지는 대표적 범용 에폭시수지인 DGEBA (diglycidylether of bisphenolA)와 방향족아민 경화제 diaminodiphenyl methane (DDM), diaminodiphenyl sulphone(DDS) 각각을 1:1의 당량비로 혼합하여 동일한 조건으로 경화하였다. 반응특성, 열 안정성, 에폭사이드기의 전환율, shrinkage(%), 유리전이온도와 선팽창계수, 기계적특성 그리고 굴곡 파단특성을 알아보기 위하여 각각 DSC 분석, TGA 분석, FT-IR 분석, 밀도측정, TMA 분석, 인장시험과 3점 굴곡시험, 광학현미경 시험을 행하였다. 그 결과, 에폭시수지 경화물의 분석, 밀도측정, TMA 분석, 인장시험과 3점 굴곡시험, 광학현미경 시험을 행하였다. 그 결과, 에폭시수지 경화물의 특성은 경화제의 벤젠링 사이의 관능기 구조에 따라 매우 큰 영향을 받았다. 즉, 벤젠링 사이에 길이가 길고 bulky한 술폰기를 포함한 DDS는 epoxiderl의 전환율, shrinkage(%), 유리전이온도, 인장탄성율, 인장강도, 굴곡탄성율 및 굴곡강도의 값이 길이가 짧고 compact한 메틸기를 가지는 DDM 경화물계 보다 높게 나타났지만, 최대발열온도, 열안정성, 선팽창계수의 값은 낮게 나타냈다. 이것은 술폰기의 강한 전기음성도와 메틸기의 전기 양성적인 repulsive한 성질의 차이와 epoxide group의 전환율의 영향인 것으로 판단된다. 굴곡 파단면의 관찰 결과는 DDM경화물계의 feather like structure의 각개 grain의 크기가 DDS 경화물계 보다 작은 것을 확연하게 보여준다.gG1 항체 합성은 spleen B cell과는 달리 TGF-$\beta$3에 의해 증가하였다. 본 실험의 결과는 전반적으로 TGF-$\beta$3가 TGF-$\beta$1과 비슷한 정도로 마우스 B cell의 항체합성에 영향을 미침을 보여준다. 그렇지만, 생체 내에서TGF-$\beta$3의 발현조절이 TGF-$\beta$1과 다를 것으로 예상됨으로 과연 TGF-$\beta$3가 B cell 분화에서 중요한 조절인자로 작용할지는 좀 더 연구되어야 할 것이다.적을 볼 때 적극적으로 수술에 임하는 것이 바람직하다고 사료된다.나타나 이의 규명을 위해서는 향후 p53 단백의 유전자 변이와 두 단백의 발현과 환자의 생존율과의 상관관계에 대한 연 구가 요할 것으로 사료된다.을 줄이기 위한 대책이 도움이 될 것으로 사료된다.4.00$\pm$0.14, 2.50$\pm$ 0.31, 4.02$\pm$0.70으로 기준(1.84$\pm$0.21)에 비하여 IP군과 10 mM 칼슘 전처치군에서 유의하게 증가하였다 (p<0.05). 그러나 허혈대조군에서는 두 분획 모두 기준선과 비교하여 큰 차이가 없었다. 결론: 이상으로 적출 관류 토끼심장에서 장시간 동안의 허혈전 높은 농도의 칼슘으로 전처치하면 허혈후 재관류시 심근기능의 회 복증가는 기대하기 어려우나 IP와 유사한 심근괴사 범위 감소효과가 있으며 이러한 효과는 아마도 칼슘의 매개에 따라 PKC활성화가 일어남으로써 나타나는 것으로 생각된다. 점을 함께 고려하면 그룹 B에서의 더 큰 증폭 효과가 광배근의 활성도 및 수축력의 차이로부터 기인한다고 평가할

• 한국포장학회지
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• 제21권1호
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• pp.35-40
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• 2015

결구상추는 급식업체에서 로컬리즘을 바탕으로 한 요구로 인해, 국내 생산품의 주년 공급이 필요하다. 그러나 하절기에 고온과 강우로 인해 적절한 결구상추의 공급이 원활하지 않다. 따라서 결구상추를 지속적으로 미리 저장하여, 출하가 어려울 때도 원활하게 공급하고자 하였다. 본 연구에서는 포장 및 저장방법에 따라 결구상추를 관행적으로 수확하여 PP플라스틱 농산물 유통상자에 단순 저장과, 결구상추의 줄기(경정) 10 cm 이상 남겨 부직포에 감싸서 저장, 상자에 농산물 식품 포장재인 LDPE 미세천공 필름을 덮어 저장하였으며, 또한 개별적으로 LLD-PE 포장재로 랩 포장하여 저장하였으며, 저장 온도는 $2^{\circ}C$에서 수행하였다. 저장 후의 포장 방법별 외관품위 및 생체중 감소에서는 개별적으로 랩 포장한 것이 21일까지의 단기적 저장에서 가장 좋았으며, 줄기를 보존하여 저장한 것, 상자에 필름 외피복, 무포장 저장 순이었다. 따라서 결구상추는 단기저장 시에 개별적인 포장 저장(저장방법 C)이 저장 3주까지 비교적 선도가 좋아, 결구상추의 단경기 원활한 공급을 위해 보급 가능한 기술로 보인다. 줄기를 물올림하면서 보존하는 방법(저장방법 D)은 재배방법과 연계하여 방법을 개선한다면, 새로운 저장방법으로 강구(講究)될 수 있을 것으로 예상된다. 결구상추의 단경기 공급을 위해서 생산이 어려운 시기에 포장과 저장방법을 개선함으로써 수급조절에 원활히 할 수 있는 가능성을 확인하였으나, 보다 선도를 유지하기 위해서는 국내 생산될 저장과 유통여건에 맞춘 추후의 연구가 더 필요할 것으로 생각된다.