• Title/Summary/Keyword: life-history traits

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Historical Look at the Genetic Improvement in Korean Cattle - Review -

  • Kim, J.B.;Lee, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.10
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    • pp.1467-1481
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    • 2000
  • The Korean cattle industry is important to farming households, the national economy, and the security of foodstuffs in Korea. Since Korean cattle have had inferior ability to produce meat, the Korean cattle industry aimed to improve the meat production ability and to increase numbers to meet the demand from the growing beef cattle market in Korea. This paper reviews the history of the Korean cattle industry and surveys the efforts devoted to improve genetic abilities of the Korean cattle. Discussed are current situations of the Korean cattle industry, projects related to improvement of Korean cattle, Korean cattle's genetic characteristics of economic traits, and some issues to deal with.

Genetic Structure in Korean Populations of Hosta capitata (Liliaceae)

  • Chung, Myong-Gi
    • Journal of Plant Biology
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    • v.37 no.3
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    • pp.277-284
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    • 1994
  • I investigated levels of genetic diversity, population genetic structure, and gene flow in Hostacapitata, a herbaceous perennial native to South Korea and southwestern Japan. Starch gel electrophoresis was conducted on leaves collected from 310 plants in 19 Korean populations. Twenty-two of 25 putative loci examined were polymorphic in at least one populatin and the mean number of alleles per locus was 1.65. In addition, mean expected heterozygosity within populations (Hep=0.153) was higher than average values for species with similar life history traits. Significant differences in allele frequency were detected between populations at all loci (P<0.01), and slightly over 30% of the genetic variation was found among populatins (GST=0.308). Indirect estimates of the number of migrants per generation (Nm) (0.506, calculated from GST; 0.852, calculated from the mean frequency of ten private alleles) indicate that gene flow is restricted among the isolated Korean populations of H. capitata. Factors contributing to the high levels of genetic differentiation among populations of H. capitata include small and discrete populations, human disturbance, and low frequencies of pollinator foraging behavior.

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A Study On Succession and Re-writing of 'Black Film', American Youth Film Director Ryan Coogler - Centering on (2013), (2015), (2018) ('흑인영화(black film)'의 계승과 다시쓰기(re-writing), 미국 흑인 청년감독 라이언 쿠글러(Ryan Coogler) 연구: <오스카 그랜트의 어떤 하루(Fruitvale Station)> (2013), <크리드(Creed)>(2015), <블랙팬서(Black Panther)>(2018)를 중심으로)

  • Kang, Nae-Young
    • The Journal of the Korea Contents Association
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    • v.21 no.1
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    • pp.210-226
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    • 2021
  • The purpose of this study is to explore the American black film director Ryan Coogler and his cinema world. Coogler as a youth director directs three movies as (2013), (2015), (2018) from independence film to Hollywood film, and represents black people' life and racial discrimination base on his cultural identity. For this study, explore traits of esthetics, subject and context meaning by analyzing representative three movies. Lastly examines significance of his movies in Hollywood black film history. He represents blackness and self-reflection as a black youth director, and successfully succeed to the tradition of 'Black Film' in American film history. He also turn white patriarchal ideology upside down in Hollywood. He inherits the tradition of 'Black Film' in American film history, and simultaneously tries to re-write black film tradition. Youth director Coogler is a symbol of 'New Hollywood Black Film Power' at the 21th.

Analysis of Effects of Multiple Environmental Factors on Early Life-history for Growth and Stress Accumulation Using a Dynamic-state-dependent Model (동적상태의존모델을 이용하여 복합적 환경영향이 어류의 초기 생활사에 미치는 영향 분석)

  • Lee, Who-Seung
    • Journal of Environmental Impact Assessment
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    • v.28 no.1
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    • pp.49-62
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    • 2019
  • Environmental changes can affect life-history traits, such as growth rate and reproduction, and organisms adapt on a given environmental condition to maximize ecological fitness. This study shows the effects of water temperature and dissolved oxygen level on early growth and accumulated damage in fish using a dynamic-state-dependent model. I have hypothesized that the level of foraging activity is related to growth and stress and so the optimal level can maximize reproductive success - ultimately, fitness. The critical temperature and dissolved oxygen (DO) is also defined as inducing the maximum growth rate at the level. So, the model predicts the highest growth rate at oxygen saturation and lower growth rate at lower or higher level of DO in water. Lower DO (i.e., hypoxia) causes slower growth rate through higher amount of accumulated stress whereas higher DO (i.e., hyperoxia) induces faster growth rate, but smaller body size. In addition, I show that there is lower impact when considering simple or independent environmental factors on environmental assessment. My findings suggest that multiple environmental factors as physiological ecology approach should be considered to improve impact assessment in environmental changes and a further study is needed to develop advanced assessment tools considering multiple environmental factors.

The Sasang Constitutional Thought of Pulse Diagnosis (맥진(脈診)의 사상의학적(四象醫學的) 고찰(考察))

  • Kim, In-Tae;Lee, Soo-Kyung;Lee, Eui-Ju;Koh, Byung-Hui;Song, Il-Byung
    • Journal of Sasang Constitutional Medicine
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    • v.15 no.3
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    • pp.22-32
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    • 2003
  • The pulse diagnosis is the basic method of oriental medicine diagnosis. But in sasang constitutional medicine, it is said that it's not a major diagnotic method. But we don't have any sasang constitutional study of the pulse diagnosis. So I made this study by research of changing concept of the pulse diagnosis in chinese medical history and Dongyi Suse Bowon (longevity and life preservation in oriental medicine). The conclusion as follows. 1. There were many kinds of the pulse diagnosis in the ancient times, it has developed to simple and effective diagnotic method. Simple and effective is the major point of medical development, the 24 pulse is abridged to Floating Pulse(浮), Deep Pulse(沈), Slow Pulse(遲), Rapid Pulse(數) 2. The latter term of Chosun, the practical study was developed. In the view of the practical study, the pulse diagnosis has a lot of cricical point. Jung Yak-Yong, in his writing Mak Lon(脈論), criticize the pulse diagnosis. 3. In the sasang constitutional medicine, the constitutional diagnosis is very important. The methods of the constitutional diagnosis are three, the way of mind and greed, knowledge and deed, external figure and physical traits. But the pulse diagnosis is one of the way of external figure and physical traits, so we can't diagnose the exact constitution by the pulse diagnosis. 4. Dong-mu conclude that the pulse diagnosis is just the diagnostic way of symptom. But in the clinical situation, the ordinary symptoms are more important than the pulse diagnosis, because it is useful to know the condition of the ingestive food metabolism and the Qi-yack metabolism

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The genetically healthy terrestrial orchid Liparis krameri on southern Korean Peninsula

  • CHUNG, Mi Yoon;CHUNG, Jae Min;SON, Sungwon;MAO, Kangshan;LOPEZ-PUJOL, Jordi;CHUNG, Myong Gi
    • Korean Journal of Plant Taxonomy
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    • v.49 no.4
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    • pp.324-333
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    • 2019
  • Neutral genetic diversity found in plant species usually leaves an indelible footprint of historical events. Korea's main mountain range (referred to as the Baekdudaegan [BDDG]), is known to have served as a glacial refugium primarily for the boreal and temperate flora of northeastern Asia. In addition, life-history traits (life forms, geographic range, and breeding systems) influence the within- and among-population genetic diversity of seed plant species. For example, selfing species harbor significantly less within-population genetic variation than that of predominantly outcrossers. A previous study of two Liparis species (L. makinoana and L. kumokiri) emphasizes the role of the abovementioned factors shaping the levels of genetic diversity. Liparis makinoana, mainly occurring on the BDDG and self-incompatible, harbors high levels of within-population genetic diversity (expected heterozygosity, HeP = 0.319), whereas there is no allozyme variation (HeP = 0.000) in L. kumokiri, which is self-compatible and mainly occurs in lowland hilly areas. To determine if this trend is also found in other congeners, we sampled five populations of L. krameri from the southern part of the Korean Peninsula and investigated the allozyme-based genetic diversity at 15 putative loci. The somewhat intermediate levels of within-population genetic variation (HeP = 0.145) found in L. krameri are most likely due to its occurrence in mountainous areas that, despite being outside of the main ridge of the BDDG, still served as refugia, and a self-incompatible breeding system. Management strategies are suggested for L. krameri and L. makinoana based on the levels and distribution of genetic diversity and inbreeding.

Genetic Diversity and Population Structure of Pyrola fauriena (Pyrolaceae) in Korea (한국내 주걱노루발의 유전적 다양성과 집단구조)

  • Huh, Man-Kyu
    • Journal of Life Science
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    • v.16 no.1
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    • pp.64-70
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    • 2006
  • Starch gel electrophoresis was used to estimate genetic diversity and population structure of Pyrola fauriena H. Andr. in Korea. The percentage of polymorphic loci within enzymes was $57.1\%$. The values of genetic diversity at the species level and at the population were higher than average values for herbaceous with similar life history traits (Hes : 0.149; Hep = 0.134, respectively), whereas the extent of the population divergence was relatively low $(G_{ST}=0.082)$. $F_{IS}$, a measure of the deviation from random mating within the 12 populations, was 0.298. An indirect estimate of the number of migrants per, generation (Nm = 2.81) indicates that gene flow is moderate among Korean populations of the species. Analysis of fixation indices revealed a substantial heterozygosity deficiency in some populations and at some loci. This indicates that some populations sampled may have been substructured largely due to rhizotamous spread and decrease of population sizes.

African Indigenous Cattle: Unique Genetic Resources in a Rapidly Changing World

  • Mwai, Okeyo;Hanotte, Olivier;Kwon, Young-Jun;Cho, Seoae
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.7
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    • pp.911-921
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    • 2015
  • At least 150 indigenous African cattle breeds have been named, but the majority of African cattle populations remain largely uncharacterized. As cattle breeds and populations in Africa adapted to various local environmental conditions, they acquired unique features. We know now that the history of African cattle was particularly complex and while several of its episodes remain debated, there is no doubt that African cattle population evolved dramatically over time. Today, we find a mosaic of genetically diverse population from the purest Bos taurus to the nearly pure Bos indicus. African cattle are now found all across the continent, with the exception of the Sahara and the river Congo basin. They are found on the rift valley highlands as well as below sea level in the Afar depression. These unique livestock genetic resources are in danger to disappear rapidly following uncontrolled crossbreeding and breed replacements with exotic breeds. Breeding improvement programs of African indigenous livestock remain too few while paradoxically the demand of livestock products is continually increasing. Many African indigenous breeds are endangered now, and their unique adaptive traits may be lost forever. This paper reviews the unique known characteristics of indigenous African cattle populations while describing the opportunities, the necessity and urgency to understand and utilize these resources to respond to the needs of the people of the continent and to the benefit of African farmers.

Dynamics of alpine treelines: positive feedbacks and global, regional and local controls

  • Kim, Jong-Wook;Lee, Jeom-Sook
    • Journal of Ecology and Environment
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    • v.38 no.1
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    • pp.1-14
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    • 2015
  • Whilst it is clear that increasing temperatures from global environmental change will impact the positions of alpine treelines, it is likely that a range of regional and local scaled factors will mediate the overall impact of global scale climate drivers. We summarized 12 categories of abiotic and biotic factors as 4 groups determining treeline positions. First, there are global factors related to climate-induced growth limitation and carbon limitation. Second, there are seven regional and local factors related to treeline dynamics including frost stress, topography, water stress, snow, wind, fire and non-fire disturbance. Third, species-specific factors can control treeline dynamics through their influence on reproduction and life history traits. Fourth, there are positive feedbacks in structuring the dynamics of treelines. Globally, the commonly accepted growth limitation hypothesis is that growth at a treeline is limited by temperature. Meanwhile, positive feedbacks between canopy cover and tree establishment are likely to control the spatial pattern and temporal dynamics of many treelines. The presence of non-linear dynamics at treelines has implications for the use of treelines as barometers of climate change because the lagged responses and abrupt shifts inherent in non-equilibrium systems may combine to mask the overall climate trend.

Comparison of Genetic Diversity and Population Structure of Kalopanax pictus (Araliaceae) and its Thornless Variant Using RAPD

  • Huh, Man-Kyu;Jung, Sang-Duk;Moon, Heung-Kyu;Kim, Sea-Hyun;Sung, Jung-Sook
    • Korean Journal of Medicinal Crop Science
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    • v.13 no.2
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    • pp.69-74
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    • 2005
  • Kalopanax pictus is a long-lived woody species mostly distributed in East Asia. K. pictus has been regarded as medically and ecologically important species in Korea. Thornless castor aralia variant, local name 'Cheongsong' is an endemic to Cheongsong province in Korea. Random amplified polymorphic DNA (RAPD) was used to investigate the genetic variation and structure of Korean populations of two species. A high level of genetic variation was found in six K. pictus populations. Twelve primers revealed 49 loci, of which 29 were polymorphic (59.2%). Nei's gene diversity for K.pictus and K. pictus variant were 0.119 and 0.098, respectively. Mean of genetic diversity in K. pictus was higher than average values for species with similar life history traits. The asexual and sexual reproduction, perennial habitat, and longevity are proposed as possible factors contributing to high genetic diversity. An indirect estimate of the number of migrants per generation (Nm=0.857) indicated that gene flow was not extensive among Korean populations of K.pictus. It is suggested that the isolation of geographical distance and reproductive isolation between K.pictus and K.pictus variant populations may have played roles in shaping the population structure of this species.