• 제목/요약/키워드: relative growth

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Growth and Photosynthetic Responses of One C3 and Two C4 Chenopodiaceae Plants to Three CO2 Concentration Conditions

  • Ishikawa, Shin-Ichi
    • Journal of Ecology and Environment
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    • 제31권4호
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    • pp.261-267
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    • 2008
  • Growth and photosynthetic responses of one $C_3$ and two $C_4$ plants in the family Chenopodiaceae in three $CO_2$ concentration $([CO_2])$ conditions-low (about $243{\mu}mol\;mol^{-1}$, LC), present (about 378, PC), and high (about 465, HC)-were investigated in open top chambers. The relative growth rate (RGR) and net assimilation rate in the $C_3$ plant, Chenopodium album, increased with increasing $[CO_2]$, though the RGR was not enhanced significantly in the HC condition. The leaf area ratio and leaf weight ratio of the $C_3$ plant drastically decreased with increasing $[CO_2]$, suggesting that the $C_3$ plant invests more biomass to leaves in lower $[CO_2]$ conditions. The two $C_4$ plants, Atriplex glauca and A. lentiformis, showed relatively small changes in those growth parameters. These photosynthetic-pathway-dependent responses suggest that growth patterns of $C_3$ and $C_4$ plants have been altered by past increases in atmospheric $[CO_2]$ but that there will be relatively little further alteration in the future high-$CO_2$ world.

완전제어형 실험용 작물생육장치의 개발(II) - 복합 환경제어 시스템 - (Development of a Fully-Controlled Plant Growth System(II) - An Integrated Control System -)

  • 심규돈;류관희;노상하;홍순호
    • Journal of Biosystems Engineering
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    • 제17권4호
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    • pp.344-353
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    • 1992
  • This study was carried out to develop a fully-controlled plant growth system for studying the effects of environmental factors on plant growth. The plant growth system consists of the growth chamber, the measurement system for sensing and signal conditioning the environmental factors and the control system which includes control algorithm required for optimum operation and on-line monitoring. The results of the study on the performance of the controlled plant growth system are summarized as follows : 1. Under the light intensity of 18,000~20,000 lux, the temperature was controlled in the range of $22{\pm}0.4^{\circ}C$, the relative humidity of $70{\pm}5%$ respectively. 2. The $CO_2$ concentration was controlled in the range of $1,000{\pm}40ppm$(from 1st to 4th day) and $1,500{\pm}40ppm$(from 4th to 9th day). 3. The electric conductivity(EC) and pH of the nutrient solution were controlled in the range of $1.9{\pm}0.2mS/cm$ and $6.8{\pm}0.5pH$ respectively. 4. Under the above environmental conditions, the average fresh weight of leaf lettuce increased from 10g to 74g in 9 days with 24 hour lighting.

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Effect of Mycorrhizal Treatment on Growth of Acacia spp. On Sandy BRIS Soils in Peninsular Malaysia

  • Lee, Su See;Mansor, Patahayah;Koter, Rosdi;Lee, Don Koo
    • 한국산림과학회지
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    • 제95권5호
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    • pp.516-523
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    • 2006
  • Marginal soils such as BRlS (Beach Ridges Interspersed with Swales) soils and ex-tin mining land make up approximately 0.5 million ha or about 2% of Malaysia's land area. In the coastal areas of the east coast of Peninsular Malaysia impoverished sandy BRIS dominates the landscape with most lying idle as there is no national management plan for their utilization. A field study was carried out to see whether mycorrhizal application had any effect on the growth of three exotic Acacia spp., i.e. Acacia auriculiformis, A. mangium and Acacia hybrid (A. auriculiformis ${\times}$ A. mangium) on BRIS soils. Two types of mycorrhizal inoculum, namely, a commercially available arbuscular mycorrhizal inoculum marketed as $MycoGold^{TM}$ and an indigenous ectomycorrhizal Tomentella sp. inoculum were tested. In the initial six months, height growth of all three tree species inoculated with the arbuscular mycorrhizal inoculum was significantly improved compared to the ectomycorrhizal inoculated and uninoculated control plants. The mycorrhizal effect was not evident thereafter and repeated application of the arbuscular mycorrhizal inoculum may be necessary for continued growth enhancement. Of the three species, A. mangium had the highest relative height growth rate over the 24 months on BRlS soils.

제주도 유용 해조류 갈래곰보(Meristotheca papulosa) 야외개체군의 생장과 성숙 (Growth and Maturation of Natural Population of Meristotheca papulosa in Jeju Island)

  • 김보연;최한길;고준철
    • 한국수산과학회지
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    • 제52권1호
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    • pp.59-66
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    • 2019
  • The growth and maturation pattern of a commercial and endemic red algae Meristotheca papulosa were investigated in Jeju Island. Ecological researches were performed in a natural population of 10 m water depth in Sinheung from march 2014 to November 2015. Maximal blade length and weight of M. papulosa were 8.7 cm and 5.49 g in July 2014 and 10.7 cm and 10.17 g in September 2015, respectively. Growth in blade area of the species reached a maximum of $43.84cm^2$ and $67.41cm^2$ in July 2014 and 2015, respectively. Thalli in the field population were rarely observed from October to December but new recruits were found from January, following year. Carposporophytes were observed from June to September when bottom seawater temperatures were around $20^{\circ}C$. At the study site, seawater temperature was in the range of $14.9-25.7^{\circ}C$. Growth parameters of M. papulosa and relative abundance of carposporophytes showed significant correlation with environmental factors (temperature, salinity, DIN). In this result, we clarified the growth and maturation period of M. palpulosa, and provided effective data on the protection and management of natural populations and basic data for mass culture of the alga.

남자 중·고등학생 교복치수 설정을 위한 신체치수 분석 (Analysis of Boys' Body Sizes to Suggest a Sizing System for Middle and High School Uniforms)

  • 유은주;최혜선;이경화
    • 한국의류학회지
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    • 제37권4호
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    • pp.598-617
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    • 2013
  • This study analyzes the body sizes of young boys in order to categorize a sizing system for middle and high school uniforms. The study was based on the $6^{th}$ National Anthropometric Survey (Size Korea 2010) data. The sample size consisted of 2,317 boys between the ages of 13 and 18 years. Most measurement items increased significantly relative to age and there was rapid growth between the ages of 13 and 14 years. The growth for the chest and hip was more than the waist. The drop value 1 (difference between chest circumference and waist circumference) and the drop value 2 (difference between hip circumference and waist circumference) increased remarkably from the age of 13 to the age of 15. Therefore, the waist size decreased and chest and hip became wider relative to the age increase. Middle school students had a smaller chest and hip circumference than high school students in the comparative body measurement results for middle school students (13-15 years) and high school students (16-18 years) of the same height group. The somatotype of high school students showed a long trunk length, broad chest and shoulder.

실리콘 웨이퍼 표면에서 X-선 산만산란에 의한 기계적 손상층의 상대 정량 평가 (Relative quantitative evaluation of mechanical damage layer by X-ray diffuse scattering in silicon wafer surface)

  • 최치영;조상희
    • 한국결정성장학회지
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    • 제8권4호
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    • pp.581-586
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    • 1998
  • 초크랄스키 실리콘 기판의 뒷면에 형성된 기계적 손상이 미치는 효과에 대하여 고찰하였다. 기계적 손상의 정도는 레이저 여기/극초단파 반사 광전도 감쇠법에 의한 소수반송자 재결합 수명, X-선 단면 측정 및 습식 산화/선택적 식긱 방법으로 평가하였다. 그 결과, 웨이퍼 뒷면에 가해지는 기계적 손상의 세기가 강할수록 소수반송자 재결합 수명은 짧아지고, 산만 산란 정도와 X-선 과잉 강도의 적분값은 비례적으로 증가하였으며, 그 값을 Grade 1의 손상된 웨이퍼에서의 과잉 강도로 정규화하면 과잉 강도의 상대 정량비는 Geade 1:Grade 2:Grade 3 = 1:7:18.4이다.

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Alternaria in Food: Ecophysiology, Mycotoxin Production and Toxicology

  • Lee, Hyang Burm;Patriarca, Andrea;Magan, Naresh
    • Mycobiology
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    • 제43권2호
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    • pp.93-106
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    • 2015
  • Alternaria species are common saprophytes or pathogens of a wide range of plants pre- and post-harvest. This review considers the relative importance of Alternaria species, their ecology, competitiveness, production of mycotoxins and the prevalence of the predominant mycotoxins in different food products. The available toxicity data on these toxins and the potential future impacts of Alternaria species and their toxicity in food products pre- and post-harvest are discussed. The growth of Alternaria species is influenced by interacting abiotic factors, especially water activity ($a_w$), temperature and pH. The boundary conditions which allow growth and toxin production have been identified in relation to different matrices including cereal grain, sorghum, cottonseed, tomato, and soya beans. The competitiveness of Alternaria species is related to their water stress tolerance, hydrolytic enzyme production and ability to produce mycotoxins. The relationship between A. tenuissima and other phyllosphere fungi has been examined and the relative competitiveness determined using both an Index of Dominance ($I_D$) and the Niche Overlap Index (NOI) based on carbon-utilisation patterns. The toxicology of some of the Alternaria mycotoxins have been studied; however, some data are still lacking. The isolation of Alternaria toxins in different food products including processed products is reviewed. The future implications of Alternaria colonization/infection and the role of their mycotoxins in food production chains pre- and post-harvest are discussed.

몇 종의 벼과식물에 관한 생장동태의 비교 연구 (Comparative Study on the Growth Dynamics of Some Grasses)

  • Choung, Yeon-Sook
    • The Korean Journal of Ecology
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    • 제16권3호
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    • pp.329-339
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    • 1993
  • Effects of relative light intensity and N, P fertilization on the growth and ramet dynamics of the rhizomatous plants, Arundinella hirta, Miscanthus sinensi and Spdiopogon sibiricus were studied in Chuncheon, Kangweon-Do. Ramets emerged in one pulse a year, withered in one pulse at the end of the growing season in M. sinensis and S. sibircus stands, while the birth and death pulse in A. hirta stands were two times. Total births of ramet were 9 times and 3.6 times greater in the unshaded fertilized stands of A. hirta and M. sinensis than in the shaded, However, those of S.sibiricus were 2.1 times greater in the shaded stands. Flowering rates of A. hirta, M.sinensis and S.sibiricus I the unshaded fertilized stands were 1.8, 2.7 and 1.04 times greater than in the shaded unfertilized stands, respectively. Height of ramets of A. hirta and M.sinensis were the hightest in the unshaded fertilized stands. However, that of s.sibiricus was the highest in the shaded fertilized stand. Aboveground production of A.hirta in the fertilized stand was 2.4 times greater in the unshaded stand than in the shaded one. Results of inflorescence frequency, shoot height and the ratio of aboveground to belowground were smiliar to the total births. The added fertilizer markedly increased the ramet density and the shoot productivity of three rhizomatous plants, especially of A. hirta.

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Characterization of the Cell-Surface Barriers to Plasmid Transformation in Corynebacterium glutamicum

  • Jang, Ki-Hyo;Paul J. Chambers;Chun, Uck-Han;Margare L.Britz
    • Journal of Microbiology and Biotechnology
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    • 제11권2호
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    • pp.294-301
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    • 2001
  • The effects of including glycine and isonicotinic acid hydrazide (INH) in the growth medium (Luria broth, LBG) on the subsequent lysozyme-imduced protoplast formation and transformation efficiency of Corynebacterium glutamicum were studied. The transformation efficiency of C. glutamicum AS019 increased up to 100-fold as the ocncentrationof glycine in the media increased from 0% to 5% (w/v), relative to cells grown in the absence of glycine. The presence of 5 mg/ml INH in the growth medium led to a further 10-fold increase in transformation efficiency. In addition, this transformation protocol was successfully applied to other strains of C. glutamicum. Both chemicals affected the mycolic acid attachment to the cell surface of C. glutamicum, when INH, the relative percentage of fatty acids of AS019 to the total lipids (mycolic acid plus fatty acids) decreased from 76.9% (in LBG) to 72.9% (in LBG-2% glycine) and 66.4% (in LBG-8 mg InG/ml), thereby suggeting that these chemicals also inhibit fatty acid synthesis.

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BSC 기반 공공도서관 성과지표 모형 개발에 관한 연구 (A Study on Developing BSC-based Public Library Performance Indicator Model)

  • 김정택
    • 한국도서관정보학회지
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    • 제40권1호
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    • pp.47-71
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    • 2009
  • 공공도서관의 사명은 정보이용, 문화활동, 평생교육 등과 관련된 지역주민의 요구를 충족시키고 보다 편리하고 평등한 접근을 제공함으로써 지역사회 발전과 지역주민의 삶의 질을 향상시키는데 있다. 본 연구는 이러한 공공도서관의 사명을 달성하고 성과를 제고할 수 있는 성과지표 모형을 개발하고자 학습 및 성장 관점, 내부 프로세스 관점, 자원 관점, 이용자 관점의 4가지 관점 아래 12개의 주요성공요인, 36개의 핵심성과지표로 구성된 BSC 기반 공공도서관 성과지표 모형을 도출하고, 공공도서관 사서를 대상으로 도출된 성과지표 모형의 상대적 가중치를 산정하여 공공도서관의 사명달성과 성과제고에 어떠한 성과지표가 중요한지를 분석한 연구이다.

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