• Title/Summary/Keyword: quantitative variation

Search Result 708, Processing Time 0.026 seconds

Comparative Morphology and Seasonality of Campylaephora borealis and C. crassa (Ceramiaceae, Rhodophyta)

  • Seo, Kyung-Suk;Boo, Sung-Min
    • ALGAE
    • /
    • v.20 no.4
    • /
    • pp.325-331
    • /
    • 2005
  • Populations of Campylaephora borealis (Nakamura) Seo, Cho et Boo and C. crassa (Okamura) Nakamura show a year-around occurrence of all life-history stages. Such a concurrency of life-history stages produces problems in recognizing species in the field. Here, we invesitgated the morphological variation and life-history stages of both species using a statistical character analysis. Life-history stage was correlated with the seawater temperature in C. borealis, whereas it was dependant on biomass in C. crassa. Thalli had dichotomous branches with adaxial branchlets. The statistics showed that the seasonal change in morphology of C. borealis was significantly different from that of C. crassa in seven qualitative characters and five quantitative characters (p < 0.001), although six quantitative features including tetrasporangial size were similar in both species. The morphological difference between the two species may be due to the annual variation of branchlet number and the variance of branch subangle.

A NOTE ON QUANTITATIVE VARIATION IN PATHOGENICITY OF PYRICULARIA ORYZAE IN THE GREENHOUSE (온실에서의 벼 도열병균의 양적변이에 관한 소고)

  • Hwang Byung Kook;Lee Eun Jong
    • Korean journal of applied entomology
    • /
    • v.19 no.1 s.42
    • /
    • pp.1-4
    • /
    • 1980
  • Quantitative differences in pathogenicity of monoconidial subcultures of Pyricularia oryzae Cav. were examined. The subcultures had been isolated from a susceptible-(STL) and an intermediate type lesion (ITL), which originated from a single culture. The majority of the STL monoconidial subcultures produced more susceptible type lesions than did the ITL subcultures. The production of intermediate type lesions was similar in both groups of subcultures, whereas the ITL subcultures produced a high number of resistant type lesions. Within both groups, there was also some variation in numbers of lesions produced.

  • PDF

A Study on Picture Quality Impairing Factors and Evaulation Method for The Video Signal in Urban Mobile Reception (영상신호의 시가지 이동수신에 의한 화상열화요인의 평가법에 관한 연구)

  • Deock Ho Ha
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.30A no.3
    • /
    • pp.52-60
    • /
    • 1993
  • Fluttering ghost which is the most severs picture impairment in mobile TV reception under multipath fading environments can be detected by measuring the dynamic variation of the synchronizing pulse timing. And also, the occurrence-stucture of fluttering ghost are directly correlated with the multipath parameters. This paper describes the quantitative evaluating method of the mobile TV pictures impaired by multipath parameters by means of the spectral analysis of synchronizing timing fluctuation. The ghost-flutter curve derived from the spatial amplitue spectrum of synchronizing pulse timing fluctuation express well the spatial variation characteristic, and it has been found to be the quantitative evaluating measure of picture impairment in mobile reception. A correspondence between the ghost-flutter curve (and/or index) and picture quality opinion test results is established.

  • PDF

Quantitative Nondestructive Evaluation of Bonded Joints utilizing Pulse-Echo Ultrasonic Test (펄스-에코법을 이용한 접착접합 시험편의 정량적 비파괴 평가)

  • Oh, Seung-Kyu;Hwang, Young-Taek;Lee, Won
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.20 no.3
    • /
    • pp.157-164
    • /
    • 2003
  • The pulse-echo method is one of the most widely used ultrasonic techniques for application of nondestructive evaluation. Particularly, quantitative nondestructive evaluation of defects has been considered more important to assure the reliability and the safety of structure. Frequency energy in adhesive joints is based on the ultrasonic wave analysis. The attenuation coefficient upon wave amplitude and the frequency energy that is expressed in the term of wave pressure amplitude were utilized for the primary wave experiment. By means of a control experiment, it was confirmed that the variation of the frequency energy in adhesive joints depends on transition by stress variation. In this paper, the ultrasonic characteristics were measured for single lap joint and Double Cantilever Beam specimen with different fracture modes that was subjected to stress. Consequently, the data that was obtained from the adhesive specimen was analytically compared to the fracture mechanics parameter

Quantitative trait loci (QTLs) detection for plant regeneration ability from seed culture in rice (Oryza sativa L.)

  • Liu, Meihan;Sohn, Jae-Keun
    • Journal of Plant Biotechnology
    • /
    • v.39 no.3
    • /
    • pp.169-174
    • /
    • 2012
  • Quantitative trait loci (QTLs), which were related to the ability of callus induction and plant regeneration in seed culture of rice, were analyzed using a mapping population from a cross between the rice cultivars 'Samgang' (tongil type) and 'Nagdong' (japonica). A tongil type rice cultivar, 'Samgang' showed lower frequency (20%) of plant regeneration than that (35%) of japonica rice, 'Nagdong'. Transgressive segregations were observed for the ability of callus induction and plant regeneration from the seed-derived calli of 58 doubled haploid (DH) lines. The ability of plant regeneration of 58 doubled haploid lines showed a continuous distribution with comparatively wide range (10.0 to 66.7%) of variation. Composite interval mapping analysis was used to identify the QTLs controlling callus induction and plant regeneration ability. Four significant QTLs, qCWS6, qCWS8, qCWS9 and qCWS11, associated with callus weight per seed were detected on chromosomes 6, 8, 9, and 11 with LOD values of 3.30, 2.60, 2.70 and 2.43, explaining 36% of the total phenotypic variation. Three significant QTLs, qPR1, qPR6, and qPR11, for the ability of plant regeneration were located on chromosome 1, 6, and 11 at LOD score of 2.25, 2.15 and 2.55, accounting for 24 % of the total phenotypic variation. The present study should be useful for improving the efficiency of plant regeneration in tissue culture of indica rice by means of marker-assisted selection.

Environmental Change Uncovers Differences in Polygenic Effect of Chromosomes from a Natural Population of Drosophila melanogaster

  • Jeung, Min-Gull;Thompson, James-N.Jr;Lee, Chung-Choo
    • Animal cells and systems
    • /
    • v.1 no.4
    • /
    • pp.609-617
    • /
    • 1997
  • Polygenic variation of sternopleural bristle number was investigated at the whole chromosome level in a natural population of Drosophila melanogasfer. Fifty pairs of second and third chromosomes were analyzed at $25^\circ{C}$. Since environmental factors such as temperature influence polygenic expression of quantitative traits, whole chromosomal effects of 28 pairs from the larger original sample were measured under cycling temperature, a $10-30\circ{C}$ cycle in 24 hours, to reveal any polygenic alleles whose effects might be masked under the constant temperature. While third chromosomes typically showed a larger contribution to polygenic variation in both environments, second chromosomes showed greater sensitivity to environmental changes. Cluster analyses of second and third chromosomes produced a limited number of clusters. Such a small number of cluster's implies that there may be a small number of genes, or quantitative trait loci (QTLs), having large effects on phenotypic variation. The genetic structure assessed under constant temperature, however, did not show any correlation with the structure under cycling temperature. The discrepancy could be caused by independent response of each polygenic allele to temperature changes. Thus, polygenic structure in natural populations should be thought of as a temporally changing profile of interactions between gene and ever-changing environment.

  • PDF

Quantitative Trait Loci Affecting Rous Sarcoma Virus Induced Tumor Regression Trait in F2 Intercross Chickens

  • Uemoto, Y.;Saburi, J.;Sato, S.;Odawara, S.;Ohtake, T.;Yamamoto, R.;Miyata, T.;Suzuki, K.;Yamashita, H.;Irina, C.;Plastow, G.;Mitsuhashi, T.;Kobayashi, E.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.22 no.10
    • /
    • pp.1359-1365
    • /
    • 2009
  • We performed a genome-wide linkage and quantitative trait locus (QTL) analysis to confirm the existence of QTL affecting Rous Sarcoma Virus (RSV) induced tumor regression, and to estimate their effects on phenotypic variance in an F2 resource population. The F2 population comprised 158 chickens obtained by crossing tumor regressive White Leghorn (WL) and tumor progressive Rhode Island Red (RIR) lines was measured for tumor formation after RSV inoculation. Forty-three tumor progressive and 28 tumor regressive chickens were then used for genome-wide linkage and QTL analysis using a total of 186 microsatellite markers. Microsatellite markers were mapped on 20 autosomal chromosomes. A significant QTL was detected with marker LEI0258 located within the MHC B region on chromosome 16. This QTL had the highest F ratio (9.8) and accounted for 20.1% of the phenotypic variation. Suggestive QTL were also detected on chromosomes 4, 7 and 10. The QTL on chromosome 4 were detected at the 1% chromosome-wide level explaining 17.5% of the phenotypic variation, and the QTLs on chromosome 7 and 10 were detected at the 5% chromosome-wide level and explained 11.1% and 10.5% of the phenotypic variation, respectively. These results indicate that the QTLs in the non-MHC regions play a significant role in RSV-induced tumor regression. The present study constitutes one of the first preliminary reports in domestic chickens for QTLs affecting RSV-induced tumor regression outside the MHC region.

Quantitative Precipitation Estimation using High Density Rain Gauge Network in Seoul Area (고밀도 지상강우관측망을 활용한 서울지역 정량적 실황강우장 산정)

  • Yoon, Seong-sim;Lee, Byongju;Choi, Youngjean
    • Atmosphere
    • /
    • v.25 no.2
    • /
    • pp.283-294
    • /
    • 2015
  • For urban flash flood simulation, we need the higher resolution radar rainfall than radar rainfall of KMA, which has 10 min time and 1km spatial resolution, because the area of subbasins is almost below $1km^2$. Moreover, we have to secure the high quantitative accuracy for considering the urban hydrological model that is sensitive to rainfall input. In this study, we developed the quantitative precipitation estimation (QPE), which has 250 m spatial resolution and high accuracy using KMA AWS and SK Planet stations with Mt. Gwangdeok radar data in Seoul area. As the results, the rainfall field using KMA AWS (QPE1) is showed high smoothing effect and the rainfall field using Mt. Gwangdeok radar is lower estimated than other rainfall fields. The rainfall field using KMA AWS and SK Planet (QPE2) and conditional merged rainfall field (QPE4) has high quantitative accuracy. In addition, they have small smoothed area and well displayed the spatial variation of rainfall distribution. In particular, the quantitative accuracy of QPE4 is slightly less than QPE2, but it has been simulated well the non-homogeneity of the spatial distribution of rainfall.

Comparing Carbon Reduction Estimates for Tree Species from Different Quantitative Models

  • Hyun-Kil Jo;Hye-Mi Park
    • Journal of Forest and Environmental Science
    • /
    • v.39 no.3
    • /
    • pp.119-127
    • /
    • 2023
  • In this study, quantitative models were applied to case parks to estimate the carbon reduction by trees, which was compared and analyzed at the tree and park levels. At the tree level, quantitative models of carbon storage and uptake differed by up to 7.9 times, even for the same species and size. At the park level, the carbon reduction from quantitative models varied by up to 3.7 times for the same park. In other words, carbon reduction by quantitative models exhibited considerable variation at the tree and park levels. These differences are likely due to the use of different growth environment coefficients and annual diameter at breast height growth rates and the overestimation of carbon reduction due to the substitution of the same genus and group model for each tree species. Extending the annual carbon uptake per unit area of the case park to the total park area of Chuncheon a carbon uptake ranging from a minimum of 370.4 t/yr and a maximum of 929.3 t/yr, and the difference can reach up to 558.9 t/yr. This is equivalent to the carbon emissions from the annual household electricity consumption of approximately 2,430 people. These results suggest that the indiscriminate application of quantitative models to estimate carbon reduction in urban trees can lead to significant errors and deviations in estimating carbon storage and uptake in urban greenspaces. The findings of this study can serve as a basis for estimating carbon reduction in urban greening research, projects, and policies.