• Restorative Dentistry and Endodontics
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• 제47권1호
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• pp.6.1-6.9
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• 2022

Objectives: This study investigated the internal morphology of mesiobuccal (MB) roots of maxillary molars with a second mesiobuccal (MB2) canal. Materials and Methods: Forty-seven maxillary first or second molars from Brazilians were scanned using micro-computed tomography. The following measurements were obtained from the MB roots: root thickness, root width, and dentin thickness of the buccal aspect of the first mesiobuccal (MB1) canal, between the MB1 and MB2 canals, and the palatal aspect of the MB2 and MB1 canals at 3 mm from the root apex and in the furcation region. For statistical analysis, the Student's t-test and analysis of variance with the post-hoc Tukey test were used (α = 0.05). Results: In maxillary molars with an MB2 canal, MB roots were significantly thicker (p = 0.0014) and narrower (p = 0.0016) than in maxillary molars without an MB2 canal. The dentin thickness of the palatal aspect of the MB1 canal was also significantly greater than that of MB roots without an MB2 canal at 3 mm from the root apex (p = 0.0007) and in the furcation region (p < 0.0001). In the furcation region of maxillary molars with an MB2 canal, the dentin thickness between the MB1 and MB2 canals was significantly smaller than that in the buccal and palatal aspects (p < 0.0001). Conclusions: The internal morphology of MB roots of maxillary molars with an MB2 canal revealed differences in dentin thickness, root diameter, and distance between the canals when compared with maxillary molars without an MB2 canal.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.227-231
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• 2012

Reforestation is one of the most important ways to reduce erosion soil. The objective of this study was to determine the effect of jellyfish soil amendment on seedling growth for reforestation. 100g jellyfish soil amendment was applied into planting hole for the purpose of improvement of the Chamaecyparis obtusa seedling growth. Results showed that during growing period, mortality were 4.4% for the fertilized group and 8.3% for control group. The seedling average height and root diameter were 95.0 cm and 1.07 cm in fertilized group and 40.6 cm and 0.74 cm in control group. The fertilized group was found to be superior (by 1 to 5%) to control group in terms of mortality rate, seedlings height, and root diameter. The positive growth of the fertilized group can be due the increase in soil moisture and the higher availability of nutrients to the plants from jellyfish fertilizer.

• Journal of Ginseng Research
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• 제42권2호
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• pp.208-217
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• 2018

Background: The quality differences in seedlings of medicinal herbs often affect the quality of medicinal parts. The establishment of the grading standard of Panax notoginseng seedlings is significant for the stable quality of medicinal parts of P. notoginseng. Methods: To establish the grading standard of P. notoginseng seedlings, a total of 36,000 P. notoginseng seedlings were collected from 30 producing areas, of which the fresh weight, root length, root diameter, bud length, bud diameter, and rootlet number were measured. The K-means clustering method was applied to grade seedlings and establish the grading standard. Results: The fresh weight and rootlet number of P. notoginseng seedlings were determined as the final indices of grading. P. notoginseng seedlings from different regions of Yunnan could be preliminarily classified into four grades: the special grade, the premium grade, the standard grade, and culled seedlings. Conclusion: The grading standard was proven to be reasonable according to the agronomic characters, emergence rate, and photosynthetic efficiency of seedlings after transplantation, and the yields and contents of active constituents of the medicinal parts from different grades of seedlings.

• Journal of Plant Biology
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• 제16권1_2호
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• pp.1-5
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• 1973

Six young trees of Alnus tinctoria grown in isolation, each having different growing stage, were selected and the surface area of their roots, stems and leaves was determined. Each of the roots of more than 0.2mm in diameter and stems was cut at intervals of 10cm and their surface area was calculated with 2$\pi$rl from the average diameter (2r) of both sections (upper and lower) by making cylindrical estimation of the cut pieces. The leaf area measured was only one side area, and the volume of cut piece and amount of dry matter of each organ were also measured. The percentage to the surface area of the whole plant body by each organ was 4-12% in root, 7-9% in stem and 69-89% in leaf, respectively. There was relatively a little individual difference. However, the surface area ratios of root and stem showed a slightly increasing tendency while that of leaf decreasing according to the growing stage. The ratio of sum leaf area index (LAIi) was 2.3-4.0$m^2$/$m^2$-and that of the surface area index(SaIi) was 0.16-0.33$m^2$/$m^2$, respectively. It has been known that the stem surface area(SAI) to the leaf area index(LAI) is within the range of 31-53%, but the SAIi is within the range of 8-11% of the LAIi.

• 생물환경조절학회지
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• 제4권2호
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• pp.152-158
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• 1995

고추의 양액재배에서 근권온도와 양액중 질소형태의 관계를 알아보기 위하여 3수준 (18$^{\circ}C$, 22$^{\circ}C$, 26$^{\circ}C$의 근권온도에서 양액중 질소형태의 비율을 달리하여 (NO$_3$-N/NH$_4$-N = 10:0, 8:2), 고추의 생육, 수량, 광합성속도, 엽록소 함유율 및 근의 활성에 미치는 영향에 대하여 검토하였다. 초장, 엽수, 경경과 엽, 근의 생체중 및 건물중은 근권온도에 의한 영향은 없었으나, NH$_4$-N의 첨가에 의하여 18$^{\circ}C$, 22$^{\circ}C$, $25^{\circ}C$의 모든 근권온도에서 초장, 엽수, 경경과 엽, 근의 생체중 및 건물중은 증가하였다. 고추의 과장은 18$^{\circ}C$와 26$^{\circ}C$의 근권온도에서 NH$_4$-N의 첨가에 의하여 약간 길어지는 경향이었고, 주당 과수 및 수량은 NH$_4$-N의 첨가에 의하여 모든 근권 온도에서 증가하였다. 광합성속도는 근권온도가 높아질수록 저하되었으나, NH$_4$-N의 첨가에 의하여 18$^{\circ}C$, 22$^{\circ}C$, 26$^{\circ}C$의 모든 근권온도에서 유의적으로 높아졌다. 엽록소 상대적함유량은 22$^{\circ}C$의 근권온도에서 높아졌으며, NH$_4$-N의 첨가에 의하여 18$^{\circ}C$, 22$^{\circ}C$, 26$^{\circ}C$의 모든 근권온도에서 높아졌다. 근의 활성은 26$^{\circ}C$의 근권온도에서 높아졌고, NH$_4$-N의 첨가에 의하여 18$^{\circ}C$, 22$^{\circ}C$, 26$^{\circ}C$의 모든 근권온도에서 높아졌다.

• 한국약용작물학회지
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• 제20권4호
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• pp.231-237
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• 2012

These studies were conducted to provide basic information on Korean ginseng cultivars and breeding lines (Panax ginseng C. A. Mey.) and to identify the variations that can be utilized in ginseng breeding programs. The agronomic characteristics was used to clarify the genetic relationships among Korean ginseng cultivars and breeding lines and to classify them into distinct genetic groups. Angle of petiole and number of fibrous root showed a wide variation from $15.0{\sim}67.8^{\circ}$ and 0~5, respectively. The average plant length was 54.2cm with a range of 37.9~64.8cm and the average stem diameter was 5.6mm with a range of 4.0~7.5mm. The average stem length was 31.9cm with a range of 21.8~37.9cm and the average root weight was 38.1 g with a range of 23.0~52.0 g. The 24 Korean ginseng cultivars and breeding lines were classified into 4 groups based on agronomic characteristics using the complete linkage cluster analysis. The I, II, III and IV groups included the 60.8%, 7.4%, 13.1% and 8.7% of the cultivars and breeding lines, respectively. The breeding lines in group I could be characterized as the group with the highest growth characters and yield components, such as plant length, stem diameter and root weight. The root weight, the yield component, had highly significant positive correlations with stem diameter, plant length and stem length.

• 한국산림과학회지
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• 제109권3호
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• pp.281-290
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• 2020

본 연구는 식재밀도가 느티나무 조림목의 초기 생장에 미치는 영향을 구명하고자 수행되었다. 연구지는 경북 경산과 전북 순창이며, 2015년 3월 말 느티나무 노지묘(1-0)를 4처리 밀도(3천, 5천, 7천, 10천본 ha^-1)로 식재하였다. 2019년까지 매년 9월에 조림목의 근원경과 수고를 측정하였고, H/D율과 수간 재적을 계산하였다. 모든 조사지에서 식재밀도가 증가할수록 근원경 및 수고 생장이 높아지는 경향을 보였으며, 수간 재적은 10천본 ha^-1 처리구에서 가장 높게 나타났다. 그러나 생존율과 H/D율은 식재밀도에 따른 차이가 없었다. 식재후 5년차에, 경산 지역에서의 근원경, 수고, 수간 재적은 순창 지역에서보다 높게 나타났다. 그러나, 입지 환경이 다른 두 조사지 모두에서 식재밀도 증가에 따라 조림목의 초기 생장이 향상되는 동일한 경향을 확인할 수 있었다. 본 연구는 10천본 ha^-1의 식재밀도가 느티나무 조림목의 초기 생장을 향상시키기 위한 적정 식재밀도임 확인하였으며, 느티나무의 조림학적 특성으로서 밀식처리에 의해 초기 생장이 향상될 수 있다는 점을 제안한다.

• 한국농림기상학회지
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• 제2권4호
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• pp.198-203
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• 2000

스트로브잣나무(Pinus strobus)가 광환경에 따라서 생장량과 엽록소함량이 어떻게 변화하는가를 관찰하기 위해서 스트로브잣나무 1-1묘목을 대상으로 실험하였다 광도는 피음막으로 자연광 상태(1800 umo1 m$^{-2}$ s$^{-1}$),자연광의 75% 광도(1350 $\mu$mol m$^{-2}$ s$^{-1}$), 자연광의 50% 광도(900 $\mu$mol m$^{-2}$ s$^{-1}$), 자연광의 25% 광도(450 $\mu$mol m$^{-2}$ s$^{-1}$) 4가지로 조절하였다. 이들 묘목을 각각 상주대학교 묘포장에 30cm$\times$30cm 간격으로 식재하여 10개체씩 수확하여 수고, 근원경, 신초, 물질생산량 및 엽록소 함량을 비교하였다. 수고, 근원경, 신초, 물질 생산량은 광도가 높은 실험구에서 공통적으로 가장 좋았다. 특히 물질생산량 가운데 뿌리부분이 광도가 낮아질수록 가장 민감하게 줄어들었다. 엽록소함량(a, b그리고 a + b)은 공통적으로 광도가 가장 낮은 실험구인 25%의 광도에서 제일 낮은 값을 보였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.274-274
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• 2017

Temperature has an adverse effect for potential growth and development of Codonopsis lanceolata. The present study examined the responses of growth, yield and mineral element contents under temperature variables in C. lanceolata. Plant height exhibited the best result as being 2 m or higher the open field culture, while the growth is the most restricted in the $30^{\circ}C$. The open field culture also had the largest number of leaves in the early stage of growth. The number of leaves and the height tended to be increased with the temperature of $20^{\circ}C$ and $25^{\circ}C$. The number of branches showed no significance as 32 branches and 26 branches in open field culture and $20^{\circ}C$, respectively. The smallest number of branches was observed in the $30^{\circ}C$ with 15 branches. The leaf color recorded the lowest value in the open field culture unlike the growth above the ground. But all other temperature had no significance with the leaf color value between 50.0 and 52.6. The elevated temperature induced the thinner and shorter diameter and length of root. However, the root diameter was not significantly changed with the change of 1.8 cm and 2.1 cm at open field culture, with $20^{\circ}C$ and $25^{\circ}C$, respectively. The fresh weights of the primary root and lateral roots were 6.3 g and 3.1 g, respectively, at the high temperature. The result showed the thickening of the lowest part under the ground as restricted. The fresh weights of the main root and lateral root were the highest on the open field culture, 20.6 g and 12.2 g, respectively. The contents of cellulose were the highest as 4.41% in the $20^{\circ}C$, followed by the open field culture, $25^{\circ}C$ and $30^{\circ}C$. The higher temperature reduced the contents of cellulose. Moreover, P showed higher ratio in the high temperature while Ca and Mg exhibited the higher ratio towards the low temperature. On the contrary, minor quantity (less than 1%) of mineral nutrients was observed towards all temperature variables.

• 한국약용작물학회지
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• 제6권3호
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• pp.193-197
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• 1998

작약(芍藥)의 화뇌제거시기가 생육(生育), 건근수량(乾根收量) 및 Paeoniflorin함량(含量)에 미치는 영향을 구명코자 시험연구한 결과는 다음과 같다. 1. 작약 재배시(栽培時) 화뇌제거에 따른 경장은 무제거에 비하여 $7{\sim}9cm$정도 제거된 만큼 짧아졌으며, 경수와 경직경은 차이가 없었다. 2. 화뇌제거에 따른 뿌리수와 생근중은 제거시기가 빠를수록 증가하였으며 , 건근수량은 화뢰크기가 10mm정도 될 때 제거한 것이 1,647/10a으로 무제거에 비하여 27% 증수되어 가장 많았다. 3. 화뇌제거시기별 paeoniflorin 함량은 뿌리굵기 5mm와 10mm에서는 무제거와 일정한 경향이 없었고, 15mm이상부터는 화뢰를 일찍 제거한 것이 화뢰 무제거보다 증가되었다. 4. 잎, 줄기의 paeoniflorin 함량은 잎이 줄기보다 높았으며, 생육초기에 높고 후기로 갈수록 낮아졌는데, 화뢰를 제거한 것이 무제거에 비하여 높았다.