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The Variation of Leaf Form of Natural Populations of Quercus variabilis in Korea (굴참나무 천연집단(天然集團)의 엽형(葉型) 변이(變異))

  • Song, Jeong-Ho;Park, Mun-Han;Moon, Heung-Kyu;Han, Sang-Urk;Yi, Jae-Seon
    • Journal of Korean Society of Forest Science
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    • v.89 no.5
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    • pp.666-676
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    • 2000
  • For the study of morphological variation of Q. variabilis natural population in Korea, 19 populations were selected through the country in considering latitude, longitude, and geographical characters. Thirty trees were randomly selected from each population and 60 mature leaves were sampled from each tree. Four characters (leaf blade length, maximum blade width, petiole length, and vein number) were measured, and their ratios (the ratio of blade length to maximum blade width, the ratio of blade length to petiole length, the ratio of petiole length to vein number, upper 1/3 blade width to maximum blade width, and upper 1/3 blade width to lower 1/3 blade width) were calculated. 1. Analysis of variance for all leaf characters were significantly different among populations and among individuals within population. Contributions of variance among individuals within population in all the characters were higher than those among populations. Therefore, selection of plus trees may be preferable to desirable populations for breeding program of Q. variabilis. 2. Among principal component analysis for leaf characters, primary 2 principal components appeared to be major variables for leaf form of Q. variabilis because of the loading contribution of 80.5%. The first contribution component was petiole length/vein number and petiole length ; the second one was upper 1/3 blade width/maximum blade width, upper blade width/lower 1/3 blade width and vein number, respectively. 3. Latitude was positively correlated with blade length/maximum blade width and blade length/petiole length, but negatively correlated with petiole length/vein number, upper 1/3 blade width/maximum blade width, upper 1/3 blade width/lower 1/3 blade width, petiole length, and vein number. But, for longitude and altitude the former two traits and the later five traits exhibited the negative and positive correlation, respectively. 4. Cluster analysis using complete linkage method for leaf characters showed two groups to Euclidean distance 1.6. They were group I of population 1. 4, 5, and 13 and group II of population 2, 3, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, and 19. However, group II was divided again to Euclidean distance 1.3, that is a group including population 3, 7, 10, 14, 15, and 17(group II-1) and the other group comprising population 2, 6, 8, 9, 11, 12, 16, 18, and 19(group II-2). This cluster could be mainly observed due to difference among population in aspect (group I : NE, group II-1 : SE, and group II-2 : SW).

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Effects of the Artemisia capillaris Extract on the Hepatotoxicity in Ethanol-induced Rats (에탄올 투여 랫트에서 인진쑥 열수 추출물이 간 독성 저하에 미치는 영향)

  • Yu, Keun-Hyung;Lee, Sun-Yeop;Yang, Hyun-Mo;Ham, Young-Ahn;Lee, Soo-Ung;Chae, Seoung-Wan;Lee, Yong-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.10
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    • pp.1560-1566
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    • 2013
  • This study was conducted to find out the effects of aqueous extract from the leaves of Artemisia capillaris (AA) on the reduction of hepatotoxicity induced by ethanol in rats. In this experiment, Sprague Dawley rats were used in the experimental groups, which were divided into 5 groups; normal group, ethanol+UDCA (ursodeoxycholic acid)-treated group (positive control), ethanol-treated group (control), ethanol+Artemisia capillaris aqueous extract-treated group (200 mg/kg of BW) and ethanol+Artemisia capillaris aqueous extract-treated group (400 mg/kg of BW). AST (aspartate aminotransferase), ALT (alanine aminotransferase), GGT (gamma(${\gamma}$)-glutamyl transferase) and LDH (lactate dehydrogenase) activities of the ethanol+Artemisia capillaris aqueous extract-treated group (400 mg/kg of BW) were significantly decreased compared to that of the ethanol-treated group (P<0.05). The triglyceride level of the ethanol-treated group was significantly increased and the HDL-cholesterol level was significantly decreased compared to the normal group (P<0.05). On the other hand, the triglyceride level was significantly decreased (P<0.05) and the HDL-cholesterol level was significantly increased (P<0.05) in the ethanol+Artemisia capillaris aqueous extract-treated groups. Superoxide dismutase (SOD) activity was enhanced significantly (P<0.05) in the ethanol+Artemisia capillaris aqueous extract-treated groups. Also, malondialdehyde contents were decreased in this group (P<0.05). Histologically, in the control group, there was a mild degenerative change around central venule. The AA treated group showed well preserved lobular architectures with no evidence of steatosis or liver damage in aqueous extract from the leaves of Artemisia capillaris treated group (H&E, ${\times}20$). As the results of this study, it is thought that Artemisia capillaris aqueous extract may have effects on the improvement of hepatic damage by ethanol.

Assessment of Dynamic Stereoacuity of Adults in their 20s' with Howard-Dolman Test (하워드-돌먼 입체검사를 이용한 20대 성인의 동적 입체시 평가)

  • Shim, Hyun-Suk;Choi, Sun-Mi;Kim, Young-Cheong
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.1
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    • pp.61-66
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    • 2015
  • Purpose: In this study, dynamic stereoacuity of 20s' adults were measured by using the Howard-Dolman test(H-D TEST, Bernell, U.S.A), and compared of male and female. And the correlation between dynamic stereoacuity and PD(pupillary distance), and between dynamic stereoacuity and anisometropia caused by difference in the spherical refractive power of the left and right eyes were analyzed. Methods: The mean age of $22.68{\pm}0.50$(20~29)years old, 20s' 63 adults (30 male, 33 female) were conducted for this experiments. After the full correction of subject's refractive error, dynamic stereoacuity was measured 5 times for 1 subject at 2.5 m distance using the H-D test. at 2.5 distance. Results: The mean of dynamic stereoacuity was $28.44{\pm}25.03$ sec of arc for total subjects, $28.23{\pm}23.34$ sec of arc for male, and $28.63{\pm}26.83$ sec of arc for female. In the dynamic stereoacuity classified by the range of inter-pupil distance (IPD), the dynamic stereoacuity was $33.87{\pm}18.53$ sec for the IPD being under 59.80 mm, $26.24{\pm}25.26$ sec of arc for 59.81~66.15 mm, $34.60{\pm}25.65$ sec of arc for over 66.15 mm. However, there were no significant differences between 3 groups (P=0.73, r=0.03). In dynamic stereoacuity classified by the refractive error difference between two eyes, dynamic stereoacuity was $26.81{\pm}24.86$ sec of arc for the under 1 D, $41.45{\pm}24.18$ sec of arc for over 1 D, and there was no significant difference between two groups (P=0.15, r=0.15). Conclusions: Dynamic stereacuity by the H-D test in 20s adults showed that there was no significant differences between male and female, and PD and anisometropia did not have a significant impact upon the dynamic stereoacuity.

Cardiovascular and Perceived Exertion Response to Treadmill Running and Cycle Ergometer Exercise in Responder and Nonresponder Acute Coronary Syndrome Patients (심장재활에 참여한 급성 관상동맥증후군 환자에서 약물 반응과 운동 형태의 변화에 따른 심혈관과 운동자각도의 반응)

  • Kim, Young-Joo;Kim, Chul-Hyun
    • Journal of Life Science
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    • v.18 no.9
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    • pp.1263-1270
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    • 2008
  • The purpose of this study is to investigate the effect of exercise mode and anti-hypertensive drug responding status on the cardiovascular response and perceived exertion in acute coronary syndrome (ACS) patients. Seventy-five patients who participated in six-week exercise rehabilitation therapy performed a treadmill running and a cycle ergometer exercise at intensities of 60%HRR and 85%HRR respectively. Systolic and diastolic blood pressure, mean arterial blood pressure (MAP), rate pressure production (RPP), and ratings of perceived exertion (RPE) were measured. The results of cardiovascular response by the different exercise modes with moderate and intensive intensity of anti-hypertensive drug responder and nonresponder ACS patients were following: First cycle ergometer exercise induced significantly higher SBP, DBP, MAP, RPP and MAP than treadmill running exercise at the intensities of 60%HRR and 85%HRR in both anti-hypertensive responder and nonresponder ACS patients (p<0.05). Secondly anti-hypertensive nonresponder ACS patients had significantly higher DBP and MAP that anti-hypertensive responder ACS patients at all the exercise modes (p<0.05). Finally there was no difference of RPP between anti-hypertensive responder and nomresponder ACS patients, although anti-hypertensive nonresponder ACS patients showed higher blood pressure and RPP than anti-hypertensive responder ACS patients. In conclusion, cycle ergometer induced increased cardiovascular response at same intensities of treadmill running exercise and anti-hypertensive nonresponder ACS patients had even more increased cardiovascular response than anti-hypertensive responder ACS patients with no difference in perceived exertion during exercise. These results suggested that cycle ergometer exercise should be greatly careful with the risk of higher blood pressure, especially for those who are patients with hypertensive blood pressure.

A Study on the Sales Promotion Functions of Packaging Elements Using AHP -Focusing on Vitamin Water- (AHP를 이용한 패키징이 소비자의 제품선호도에 미치는 영향 측정 -비타민워터를 중심으로)

  • Kang, Donghyun;Ko, Euisuk;Song, Kihyeon;Kim, Deuksoo;Kim, Jaineung
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.20 no.3
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    • pp.113-120
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    • 2014
  • Packaging has played important function on marketing as a silent salesman. As an interface of consumer and products, packaging fulfills several functions such as protection, sales promotion, communication and convenience during the distribution process. For the appearance of self-service sales method, packaging could be regarded as important salesman influencing consumers' preference on shelf in the shop. In this study, Vitamin water was selected as the proper target product for lower impact of prices and brands. With previous studies, Vitamin water packaging elements were classified as 'packaging material', 'packaging shape', 'label color', 'logo layout', then each packaging element was consist of details. To measure the influence of each packaging element on consumers' preference quantitatively and to minimize respondent's subjective judgment, Analytic Hierarchy Process (AHP) was used as a tool. Through AHP result, packaging element of the most influence on consumers' preference is 'label color (0.370)', and 'container shape (0.246)', 'container material (0.230)', 'logo layout (0.154)' was in order. Among the detail packaging element, 'plastic (0.405)' has the greatest influence in 'container material' and 'cylinder (0.423)' in 'container shape', 'magenta (0.329)' in 'label color', 'vertical layout (0.572)' in 'logo layout'.

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Biogeochemical Studies on Tidal Flats in the Kyunggi Bay: Introduction (경기만 부근 갯벌의 생지화학적 연구: 서문)

  • Cho, B.C.;Choi, J.K.;Lee, T.S.;An, S.;Hyun, J.H.
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.10 no.1
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    • pp.1-7
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    • 2005
  • Tidal flats have been regarded to carry out transformation and removal of land-derived organic matter, and this purifying capability of organic matter by tidal flats is one of very important reasons for their conservation. However, integral biogeochemical studies on production and decomposition of organic matter by benthic microbes in tidal flats have been absent in Korea, although the information is indispensable to quantification of the purifying capability. Our major goals in this multidisciplinary research were to understand major biogeochemical processes and rates mediated by diverse groups of microbes dominating material cycles in the tidal flats, and to assess the contribution of benthic microbes to removal of organic matter and nutrients in the tidal flats. Our study sites were Ganghwa and Incheon north-port tidal flats that had been regarded as naturally well reserved and organically polluted, respectively. Our research group measured over 3 years primary production, biomass and community structure of primary producers, abundance and production of bacteria, enzyme activities, distribution of protozoa and protozoan grazing rates, rates of denitrification and sulfate reduction, early sediment diagenesis, primary production and respiration based on oxygen microelectrode. We analyzed major features of each biogeochemical process and their interactions. The results are compiled in the following articles in this special issue: An (2005), Hwang and Cho (2005), Mok et at. (2005), Na and Lee (2005), Yang et at. (2005), and Yoo and Choi (2005).

The Variation of Natural Populations of Pinus densiflora S. et Z. in Kangwondo - The Morphological Characteristics of Needle and Cone - (강원도 지역 소나무 천연집단의 변이에 관한 연구 - 침엽과 구과의 형태적 특성을 중심으로 -)

  • Yi, Jae-Seon;Song, Jeong-Ho;Han, Sang-Sup;Park, Wan-Geun
    • Journal of Forest and Environmental Science
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    • v.15 no.1
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    • pp.107-116
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    • 1999
  • For the study on the variation of Pinus densiflora S. et Z. natural populations. 13 stands were selected in Kangwondo region in 1994. They were located in Hyoja-Dong, Chunchon-Si [plot 1]; Sinnam-Myun, lnje-Gun [plot 2]; Buk-Myun, lnje-Gun [plot 3]; Seo-Myun, Yangyang-Gun [plot 4 and 5]; Sonyang-Myun, Yangyang-Gun [plot 6]; Toseong-Myun, Goseong-Gun [plot 7]; Synrim-Myun, Wonju-Si [plot 8]; Dunnae-Myun, Hoengsong-Gun [plot 9]; Jinbu-Myun, Pyungchang-Gun [plot 10]; Sogumgang, Kangneung-Si [plot 11]; Seo-Myun, Ulchin-Gun [plot 12]; and Mitan- Myun, Pyungchang-Gun [plot 13]. The morphological characteristics of needles and cones were investigated for twenty individual trees from each population. The results are summarized as follows: 1. Among needle characteristics, length, the number of serration. and the number of stoma row were significantly different among populations and between individuals within a population. They were 69.3~91.9mm, 25.1~28.7 per 0.5cm, and 4.1~6.2 rows for abaxial side and 2.9~4.6 rows for adaxial side, respectively. 2. Among cone characters surveyed. length and diameter were significantly different among populations and between individuals within a population. They were 31.1~43.7mm and 20.0~24.1mm, respectively. 3. A highly positive correlation was observed between the number of stoma row of abaxial side and that of adaxial side. and between length and diameter of cone. But the number of serration was negatively correlated with all traits. 4. The distance from seashore was positively correlated with needle length and the number of serration, but negatively correlated with the number of stoma row and cone length. However, the altitude was positively correlated with the number of serration, but negatively correlated with the number of stoma row and cone length. 5. Cluster analysis using average linkage method for needle and cone characteristics showed two groups to Euclidean distance 1.0. They were group I consisting of plots 1, 8, 12, and 13 and group II of plots 2, 3, 4, 5, 6, 7, 9, 10, and 11. However, group II was divided again to Euclidean distance 0.8, that is a group including plots 2, 3, 9, and 11 and the other group comprising plots 4, 5, 6, 7, and 10.

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The Influence of Field Compaction Method on the Efficiency of Compaction and the C. B. R. Value (전압방법(轉壓方法)이 전압효과((轉壓效果) 및 C. B. R. 값에 미치는 영향(影響))

  • Chung, Sang;Kang, Yea Mook
    • Korean Journal of Agricultural Science
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    • v.10 no.2
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    • pp.292-309
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    • 1983
  • This study is intended to find out the degree of compaction in field compaction, with soil type, the thickness of soil layer and the number of roller passing through the field density test and the field C. B. R. test by comparing vibration and non-vibration compactions. The results in this study are summarized as follows. 1. When the number of roller passing is few, it shows that the efficiency of the compaction by vibratory compaction is greater than that by non-vibratory compaction, the difference of the compaction ratio between vibratory and non-vibratory compaction is decreased according as the number of roller passing is more frequent. 2. Mechanizing on a large scale it is possible for a large equipment to be able to reach the point of A-1 compact ion method with three to five times of roller passing. To provide for mechanizing on a larger scale it is advisable to fix the standard by the D-2 compaction method. 3. As dry-density increases, the C. B. R. value increases, but the increasing ratio of C. B. R. value showed greater in vibrating compacting. 4. According as the number of roller passing increases, the increasing tendency of the C. B. R. Value is slow and the difference of the C. B. R. value between vibration and non-vibration compaction is large, the C. B. R. value showed greater about 20% in vibration compaction than in non-vibration compaction. 5. In C-5 soil type, with increasing the thickness of compaction, the degree of compaction is decreased. When the thickness of compaction is increased from 20cm to 30cm, the degree of compaction is decreased slowly, while the thickness of the compaction is increased from 30cm to 40cm the degree of compaction is decreased remarkably. Therefore it is advisable to compact the ground under the thickness of 30cm.

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Studies on Influence of Water-Proof Agents on the Properties of Mortar (방수제(防水劑)가 모르터의 제성질(諸性質)에 미치는 영향(影響)에 관(關)한 연구(硏究))

  • Kim, Seong Wan;Sung, Chan Yong;Kim, Sun Young
    • Korean Journal of Agricultural Science
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    • v.14 no.2
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    • pp.358-372
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    • 1987
  • This study was performed to obtain data which can be applied to use of water-proof mortars. The data was based on the properties of water-proof mortars depending upon various mixing ratios to compare those of cement mortar. The water-proof agents used were retard and accelerate type which are being used as mortar structures. The water-proof agents, mixing ratios of cement to fine aggregate were 1:1, 1:2, 1:3 and 1:4. The results obtained were summarised as follows; 1. The results of flow test, water-cement ratio was increased with the increasing of mixing ratio. 2. The permeability were increased in poorer mixing ratio and higher water pressure. 3. The bulk density was decreased with the increasing of mixing ratio, and compressive and tensile strength were increased with increasing of the bulk density. 4. At 1:1 mixing ratio, the highest strengths were showed and strengths were decreased with the increasing of mixing ratio. 5. The absorption rates were increased in- poorer mixing ratio 6. The correlation between W/C, permeability, bulk density, compressive strength and absorption rate were highly significant as a straight line, respectively.

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A Study on the Economic Analysis of Chestnut Prices and Production Forecasting (밤 가격(價格)의 경제분석(經濟分析) 및 생산예측(生産豫測)에 관(關)한 연구(硏究))

  • Song, Hyung Sop;Cho, Eung Hyouk
    • Korean Journal of Agricultural Science
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    • v.14 no.2
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    • pp.263-271
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    • 1987
  • The cyclical trend and seasonal variations of chestnut prices have been analyzed to find out the chestnut price fluctuation in Korea during 1966-1985. The optimum prices, production, and plantation area for the next twenty five years (1986-2010) have been forcasted by the derived equation models. The results of study can be summarized as follows: 1. The chestnut prices were increased by 14.67 percent per annum during 1966-1972, an d decreased by 9.24 percent during 1973-1985, due to the excessive production of chestnut. 2. The chestnut prices showed the lowest price during the harvesting season, especially in October (89.1), and highest in July (109.1). Seasonal fluctuation of chestnut prices were 0.0837 (C.V value) during 1966-1975, and 0.0706 during 1976-1985. Such a seasonal fluctuation of chestnut prices tends to be even with the passage of time. 3. The equation model of predicted chestnut prices was derived as follows : PR=117788.088 - 7.60 TC/Pop + 6.585 GNP/Pop The chestnut prices will be the lowest in 1988, but increased rapidly thereafter. 4. The equation model of optimum chestnut production was derived as follows : $${\ell}n\;PD/Pop=-8.5147-0.8267{\ell}n\;PR+3.3063{\ell}n\;GNP/Pop$$ To maintain optimum chestnut prices according to this model, chestnut production should be 133,000 ton for 1988, and 1,899,000 ton for 2010. 5. Optimum chestnut plantation area will be 4,000 ha in 1988, and thereafter total plantation area will be up to 57,400 ha in 2010.

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