• Fisheries and Aquatic Sciences
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• 제21권3호
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• pp.12.1-12.15
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• 2018

A preliminary investigation of length-weight relationship, condition factor and reproductive ecology of African pike fish, Hepsetus odoe, was conducted between June to August 2010 in Lake Eleiyele. A total of 90 samples of the fish species were caught by fishermen using gill nets. The results obtained showed that fish species had isometric growth pattern (contrary to negative allometry expected) with the growth exponent, b value of 2.64, that is not statistically different from 3 and with high statistical power of 0.866 when tested. The mean condition factor, K, was found to be 2.6, indicating that the fish species were in good condition in the study area. For reproductive biology, mean fecundity and gonadosomatic index were found to be 1349 eggs and 3.53% respectively. This study was necessary to fill the knowledge gap and provide information for management and conservation of the investigated species in the lake system. This study recommended that further research needs to be conducted because the sampling was carried out in the rainy season period and within a quarter of a year.

• 한국산림과학회지
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• 제99권5호
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• pp.726-735
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• 2010

Publications with the data on allometric equation, biomass and productivity of major oak forests in Korea were reviewed. Different allometric equations of major oak species showed site- or speciesspecific dependences. The biomass of major oak forests varied with age, dominant species, and location. Aboveground tree biomass over the different oak species was expressed as a power equation of the stand age. The proportion of tree component (stem, branch and leaf) to total aboveground biomass differed among oak species, however, biomass ranked stem > branch > leaf in general. The leaf biomass allocation over the different oak species was expressed as a power equation of total aboveground biomass while there were no significant patterns of biomass allocation from stem and branch to the aboveground biomass. Tree root biomass continuously increased with the aboveground biomass for the major oak forests. The relationship between the root to shoot ratio and the aboveground tree biomass was expressed by a logarithmic equation for major oak forests in Korea. Thirteen sets of data were used for estimating the net primary production (NPP) and net ecosystem production (NEP) of oak forests. The mean NPP and NEP across different oak forests was 10.2 and 1.9 Mg C $ha^{-1}year^{-1}$. The results in biomass allocation, NPP and NEP generally make Korean oak forests an important carbon sinks.

• The Korean Journal of Ecology
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• 제11권2호
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• pp.83-95
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• 1988

Phytomass, annual net production, respiration, annual gros production and litter fall were estimated in young Korean pine (Pinus koraiensis) plantations reforested 1,2,3,6,9 and 11 years ago, respectivly. The estimated phytomasses in terms of allometry were 0.07, 0.44, 0.58, 13.37, 32.26 and 48.42ton/ha/yr for annual net production and those of understory with harvest method were 3.70, 4.52, 5.28, 6.72, 7.56 and 5.72ton/ha for standing phytomass and 5.01, 4.71, 5.52m 6.15, 4.51 and 2.08 ton/ha/yr for annual net production at 1,2,3,6,9 and 11 year old plantation, respectively. Although the standing phytomass of understory increased gradually until 9 years thereafter decreased, that of white pine increased suddenly from 6 years after reforestation. The ratios of the annyal net production of understory to that of white pine were 71.57, 1.48 and 0.23 at 1,6 and 11 year old plantations, respectively. The net production in calorie value for whole vegetation of the plantations, respectively. The net production in calorie value for whole vegetation of the plantations increased until 9 years thereafter decreased; i.e. 224, 221, 280, 466, 527 and 494X105 kcal/ha/yr at 1,2,3,6,9 and 11 year old plantation, respectivey. The ratio of annual net production to annual gross production of the undersoty was lower than that of the pine at the same plantation age. Efficiency of solat energy untilization for net production by the pine was lower than that by understory y\until six ear old plantation but that was vice versa over 9 year old plantation. That for gross producrion by the pine was lower than that by the unsersotry at all plantations.

• 환경생물
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• 제37권4호
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• pp.618-624
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• 2019

This study aimed to determine the growth and carbon storage of planted Haloxylon aphyllum in the Aralkum Desert in Kazakhstan. Six sites afforested in 2000, 2005, 2009, 2010, 2013, and 2017 were selected. The root collar diameter(cm) and height(m) were measured for all H. aphyllum in 30 m×44 m plots. Biomass accumulation (g m^-2) and carbon storage(C g m^-2) were calculated using allometric equations and the carbon concentration data of Haloxylon species. The diameters varied from 2.5 cm to 4.3 cm and the height varied from 106.2 cm to 223.7 cm. The growth of H. aphyllum was not linearly related to the afforestation year or soil properties. Tree growth might have been influenced by variations in the microclimate, such as temperature, precipitation, and dust storms. The mean total biomass accumulation was 20.57g m^-2 and ranged from 2.42 g m^-2 to 64.53 g m^-2. The mean carbon storage was 9.70C g m^-2 and ranged from 1.12 C g m^-2 to 30.61 C g m^-2. These biomass and carbon storage estimates were smaller than those reported for other Central Asian deserts, but afforestation enabled the generation of vegetative cover and consequently, carbon sequestration in the manmade Aralkum Desert.

• 한국균학회지
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• 제37권1호
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• pp.55-59
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• 2009

버섯은 생태계에서 분해자로 역할을 담당하며, 그 양은 생태계의 건전성을 나타내는 중요한 지표이다. 버섯의 생산량을 알기 위해서는 개체를 수확하여 그 무게를 측정하여야 한다. 그러나 이 방법은 버섯 개체를 수확할 때 서식지를 훼손하고, 또한 한 지역에서 버섯의 동태를 장기적으로 관찰하는데 적합하지 못하다. 따라서 본 연구에서는 자실체의 외부 형질을 측정하고 이로부터 현존량을 추정하는 비례식을 만들었다. 사용한 버섯은 표고(L. edodes), 느타리(P. ostreatus), 팽이버섯(F. velutipes)과 종버섯(C. tenera)이다. 버섯의 자실체에서 형질 변수(갓 직경, PD; 갓 면적, PA; 대 길이, SL; 대 두께, ST)를 측정하고, 이 변수로부터 건조 생물량과의 회귀관계식을 구하였다. 그 결과 버섯 4종 모두 추정한 식에서 유의한 상관성을 보임으로써(p < 0.05), 외부 형질 변수로부터 유도된 비례식을 사용하여 버섯의 현존량을 예측할 수 있음이 확인되었다.

• Journal of Veterinary Science
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• 제21권3호
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• pp.35.1-35.11
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• 2020

Background: Despite common use of tylosin in turkeys, the pharmacokinetic (PK) data for this drug in turkeys is limited. Within a few months of growth, PK of drugs in turkeys undergoes changes that may decrease their efficacy due to variable internal exposure. Objectives: The objective of this study was to investigate the influence of age on the PK of a single intravenous (i.v.) and oral administration of tylosin to turkeys at a dose of 10 and 50 mg/kg, respectively. Methods: Plasma drug concentrations were measured using high-performance liquid chromatography with UV detection. The PK parameters were assessed by means of non-compartmental approach and were subjected to allometric analysis. Results: During a 2.5-month-long period of growth from 1.4 to 14.7 kg, the median value for area under the concentration-time curve after i.v. administration increased from 2.61 to 7.15 mg × h/L and the body clearance decreased from a median of 3.81 to 1.42 L/h/kg. Over the same time, the median elimination half-life increased from 1.03 to 2.96 h. For the oral administration a similar trend was noted but the differences were less pronounced. Bioavailability was variable (5.76%-21.59%) and age-independent. For both routes, the plasma concentration of the major tylosin metabolite, tylosin D, was minimal. Protein binding was age-independent and did not exceed 50%. Allometric analysis indicated a relatively poor predictivity of clearance, volume of distribution and elimination half-life for tylosin in turkeys. Conclusions: Age has a significant impact on tylosin PK in turkeys and dosage adjustment may be needed, particularly in young individuals.

• 대한치과교정학회지
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• 제53권3호
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• pp.185-193
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• 2023

Objective: The growth and development of the mandible strongly depend on modeling changes occurring at its ramus. Here, we investigated covariance patterns between the morphology of the ramus and the rest of the face. Methods: Lateral cephalograms of 159 adults (55 males and 104 females) with no history of orthodontic treatment were collected. Geometric morphometrics with sliding semi-landmarks was used. The covariance between the ramus and face was investigated using a two-block partial least squares analysis (PLS). Sexual dimorphism and allometry were also assessed. Results: Differences in the divergence of the face and anteroposterior relationship of the jaws accounted for 24.1% and 21.6% of shape variation in the sample, respectively. Shape variation was greater in the sagittal plane for males than for females (30.7% vs. 17.4%), whereas variation in the vertical plane was similar for both sexes (23.7% for males and 25.4% for females). Size-related allometric differences between the sexes accounted for the shape variation to a maximum of 6% regarding the face. Regarding the covariation between the shapes of the ramus and the rest of the face, wider and shorter rami were associated with a decreased lower anterior facial height as well as a prognathic mandible and maxilla (PLS 1, 45.5% of the covariance). Additionally, a more posteriorly inclined ramus in the lower region was correlated with a Class II pattern and flat mandibular plane. Conclusions: The width, height, and inclination of the ramus were correlated with facial shape changes in the vertical and sagittal planes.

• 한국산림과학회지
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• 제56권1호
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• pp.51-65
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• 1982

참대를 재료(材料)로 하여 개화후(開花後) 회복도상(回復途上)에 있는 죽림(竹林)의 생장특성(生長特性)과 합리적(合理的)인 비배에 관(關) 해석하였다. 시험지(試驗地) 죽림(竹林) 토양(土壤)은 부식질이 풍부한 사양토였으나 시비구(施肥區)에서는 무비구(無肥區)에 비하여 질소질 비료(肥料)의 흡수가 현저하게 왕성하였으며, 가리질 비료(肥料)의 계속저인 시비(施肥)가 필요(必要)한 상태였다. 개화후(開花後) 회복(回復)이 촉진됨에 따라 죽림(竹林)의 온도와 상대조도(相對照度)는 낮아지는 반면(反面) 온도(溫度)는 높아졌다. 참대의 목통직경(D)와 간장(幹長)(H)과는 $H=2.5538D^{0.5031}$인 관계식(關係式)으로 나타낼 수 있으며 죽림(竹林)의 엽면적(葉面積)은 죽림(竹林)의 생산력(生産力)을 규제하는 요인(要人)이 되고 있으므로 비개화죽의 가지치기나 벌채는 지양하여야 할 것이다. 정규분 포곡선식에서 유도한 마디길이 분포곡선식(分布曲線式)으로 각(各) 마디의 위치별 길이의 이론적(理論的)인 분포상태(分布狀態)를 얻을 수 있다. 시비(施肥) 2구(區)와 4구(區)는 비교적 길고 고른 마디길이를 가진 대나무가 많았다. 참대의 $D^2H$와 줄기의 건물중, 그리고 $D^2H$와 지상부(地上部) 건물중과의 관계(關係)는 대수그래프상에서 직선회귀를 나타냈으나 이들 사이에 비례관계는 성립되지 않았다. 상대성장법(相對成長法) 의(依)하여 추정(推定)된 대나무 지상부(地上部)의 현존량(現存量) 시비(施肥) 2, 5, 6구(區)에서 높은 치를 보였다. 최대건물량(最大乾物量)을 얻을 수 있는 N, P, K요소의 적정 시비량(施肥量)은 각각(各各) 24.20, 15.51, 8.63kg/10a였다.

• 한국발생생물학회지:발생과생식
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• 제16권2호
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• pp.101-106
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• 2012

어류의 시각 구조와 시각 기능 연구에 있어서 행동적 요인이나 환경적 요인의 중요성은 시각생태학에서 매우 중요하게 다루어지고 있으며, 볼락, Sebastes inermis에 관하여는 아직까지 초기 눈의 성장 및 발달에 관한 발생생물학적 연구가 이루어진 바가 없음을 고려하여 이에 대한 연구를 수행하였다. 볼락의 전장, 두장, 두고, 눈의 직경과 수정체 직경은 산출 직후부터 산출 후 60일까지의 단계에서 양성의 상관관계(positive allometry)를 보여주었다. 전장과 관련된 두장과 두고에서의 증가와, 두고와 관련된 눈의 직경과 수정체 직경의 성장은 거의 동형(isometric)성장을 나타내었다. 눈은 산출단계에 완전히 형성되었다. 산출 단계의 눈은 시신경 섬유층, 신경절 세포층, 내망상층, 내과립층, 외망상층, 외과립층, 외경계막, 간체, 추체층 및 상피층을 가지며, 산출 후 60일의 망막 두께는 산출 직후의 망막 두께보다 더 크다. 본 실험기간 동안, 망막의 간체와 추체층의 비율 및 외과립층과 시신경의 비율은 상당히 증가한 반면, 망막의 외망상층과 내과립층, 신경절 세포층의 비율은 현저하게 감소하였다(P<0.05). 차후, 본 연구에 사용된 볼락 망막에 대한 빛 민감성과 공간 해상력에 관한 부수 연구가 필요하리라 사료된다.

• 한국산림과학회지
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• 제35권1호
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• pp.9-14
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• 1977

은수원사시나무(${\times}$P. albaglandulosa)조림지(造林地)에서 임분밀도(林分密度)가 693본(本)/ha의 6년생(年生), 625본(本) 또는 527본(本)/ha의 9년생(年生) 임분(林分)에 대하여 상대생장법(相對生長法)으로 현존량(現存量)과 생산성(生産性)을 추정(推定)하고 생산구조(生産構造)를 분석(分析)하였다. 1. 생산구조도(生産構造圖)의 광합성부(光合成部)는 층(層)을 형성(形成)하여 광선(光線)의 투입(透入)에 효과적(効果的)인 특징(特徵)을 나타내었다. 2. 지상부(地上部) 현존량(現存量)은 6년생(年生)이 18.11 ton/ha, 9년생(年生)이 38.8~47.3ton/ha 이며, 간재적(幹材積)은 6년생(年生)이 $31.3m^3/ha$, 9년생(年生)이 $68.8{\sim}83.9m^3/ha$이었다. 3. 년순생산량(年純生産量)은 6년생(年生)에서 4.8 ton/ha/yr, 9년생(年生)에서 10.0~11.7ton/ha/yr를 얻었고. 간재적(幹材積)의 순생산량(純生産量)은 $17.9{\sim}21.1m^3/ha/yr$로 나타났다. 4. 9년생(年生)의 표준지(標準地)에서 현존량(現存量) 및 순생산량(純生産量)에 차이(差異)가 생기는 이유(理由)는 토양(土壤)의 화학성분(化學成分)에 의하지 않고 물리적(物理的) 성질(性質)에 기인(起因)하는 것으로 사료(思料)되었다.