• 인터넷정보학회논문지
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• 제22권1호
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• pp.1-11
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• 2021

Estimation of distribution algorithm (EDA) is a popular stochastic metaheuristic algorithm. EDA has been widely utilized in various optimization problems. However, it has been shown that the diversity of the population gradually decreases during the iterations, which makes EDA easily lead to premature convergence. This article introduces a hybrid estimation of distribution algorithm (EDA) with differential evolution (DE) based on self-adaptive strategy, namely HEDADE-SA. Firstly, an alternative probability model is used in sampling to improve population diversity. Secondly, the proposed algorithm is combined with DE, and a self-adaptive strategy is adopted to improve the convergence speed of the algorithm. Finally, twenty-five benchmark problems are conducted to verify the performance of HEDADE-SA. Experimental results indicate that HEDADE-SA is a feasible and effective algorithm.

• Asian-Australasian Journal of Animal Sciences
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• 제10권4호
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• pp.428-434
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• 1997

The effect of genetic diversity in sub-populations on breeding efficiency was examined with prospect of potential crossbreeding. Simulation study of selection was performed for 20 generations with 20 replications each, comparing average breeding values and inbreeding coefficients between the two breeding systemes; single population scheme and two population scheme. The different genetic levels were assumed to be caused by different gene frequencies. Phenotypes of two traits generated polygenic effect with additive 36 loci and residuals distributed normally were selected by selection index procedure. High genetic gain with less inbreeding was clearly recognized in the single population scheme, independently of difference in genetic level, economic weight and genetic correlation. Genetic correlation after selection in the single population scheme was lower than the two population scheme. When crossbreeding between the sub-population was taken into account, superiority of the two population scheme was suggested under those restrictions; difference in genetic level is moderate, selection criterion for the two traits is not far from even economic weight, and genetic correlation is positive with low to moderate value. The use of complementarity increased the possibility of the two population scheme.

• BMB Reports
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• 제49권12호
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• pp.662-670
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• 2016

The human oral cavity contains a highly personalized microbiome essential to maintaining health, but capable of causing oral and systemic diseases. Thus, an in-depth definition of "healthy oral microbiome" is critical to understanding variations in disease states from preclinical conditions, and disease onset through progressive states of disease. With rapid advances in DNA sequencing and analytical technologies, population-based studies have documented the range and diversity of both taxonomic compositions and functional potentials observed in the oral microbiome in healthy individuals. Besides factors specific to the host, such as age and race/ethnicity, environmental factors also appear to contribute to the variability of the healthy oral microbiome. Here, we review bioinformatic techniques for metagenomic datasets, including their strengths and limitations. In addition, we summarize the interpersonal and intrapersonal diversity of the oral microbiome, taking into consideration the recent large-scale and longitudinal studies, including the Human Microbiome Project.

• 한국어류학회지
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• 제21권sup1호
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• pp.52-62
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• 2009

한반도 주변 3개 해역은 서로 다른 지형과 다양한 해류의 교차로 종다양성의 근간이 된다. 또한, 복잡한 해류가 만나는 전선 주변으로는 좋은 어장이 형성된다. 그러나, 남획에 의한 자원의 감소 및 EEZ 발효에 의한 어장의 축소는 새로운 수산자원 관리법을 필요로 하게 되었다. 수산자원의 효율적 관리를 위해 우선 다양한 해양환경에 적응한 지역개체군의 실체를 파악하는 것이 필요하다. 지역개체군의 형태 및 유전에 관한 연구는 자원의 관리단위 및 구역을 명확히 하는 데 기여할 것이다. 최종적으로 해역별 수산자원의 관리방안 제시가 가능할 것으로 기대된다.

• Animal cells and systems
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• 제1권4호
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• pp.577-581
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• 1997

Species diversity of subcortical arthropod communities were assessed in two tropical regions and two temperate regions. In the tropics, communities of subcortical arthropods were more diverse in La Selva, Costa Rica, than on Barro Colorado Island, Panama. Costa Rican communties yielses higher values of both Shannon and Simpson diversity indices than Panamanian communities. Compared to Panamanian communities, Costa Rican ones supported higher measures of both species richness and evenness. Between the two temperate regions, communities of subcortical arthropods in Korea scored consistently higher values of both Shannon and Simpson indices than the ones in eastern Massachusetts, U.S.A. When individual diversity components were compared, however, Korean communities yielded exceptionally high evenness measures but lower species richness than the communities in the U.S.A. Unusually high evenness values of Korean subcortical arthropods were due to extremely low population densities of all component species.

• Journal of Microbiology and Biotechnology
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• 제23권10호
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• pp.1472-1477
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• 2013

Microalgae have been regarded as a natural resource for sustainable materials and fuels, as well as for removal of nutrients and micropollutants from wastewater, and their interaction with bacteria in wastewater is a critical factor to consider because of the microbial diversity and complexity in a variety of wastewater conditions. Despite their importance, very little is known about the ecological interactions between algae and bacteria in a wastewater environment. In this study, we characterized the wastewater bacterial community in response to the growth of a Selenastrum gracile UTEX 325 population in a real municipal wastewater environment. The Roche 454 GS-FLX Titanium pyrosequencing technique was used for indepth analysis of amplicons of 16S rRNA genes from different conditions in each reactor, with and without the algal population. The algal growth reduced the bacterial diversity and affected the bacterial community structure in the wastewater. The following in-depth analysis of the deep-sequenced amplicons showed that the algal growth selectively stimulated Sphingobacteria class members, especially the Sediminibacterium genus population, in the municipal wastewater environment.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.48-48
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• 2014

Arbuscular Mycorrhizal Fungi(AMF) is widespread symbiont forming mutualistic relationship with plant root in terrestrial forest in ecosystem. They provide improved absorption of nutrient and water, and enhance the resistance against plant pathogen or polluted soil, therefore AM fungi are important for survival and maintaining of individual or community of plant. For last decade, many studies about the functional variation of AM fungi on host plant growth response were showed that different geographic isolates, even same species, have different effect on host plant. However, little was known about functional variation of AM fungal isolates originated single population, which provide important insight about intraspecific diversity of AMF and their role in forest ecosystem. In this study, four AM fungal isolates of Rhizophagus clarus were cultured in vitro using transformed carrot (Daucus carota) root and they showed the difference between isolates in ontogenic characteristics such as spore density and hyphal length. The plant growth response by mycorrhizas were measured also. After 20 weeks from inoculation of these isolates to host plants, dry weight, Root:Shoot ratio, colonization rates and N, P concentration of host plant showed host plant was affected differently by AM fungal isolates. This results suggest that AM fungi have high diversity in their functionality in intraspecific level, even in same population.

• 한국산림과학회지
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• 제98권5호
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• pp.531-538
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• 2009

We used enzyme electrophoresis to evaluate genetic diversity in five populations of endemic ash, Fraxinus chiisanensis in Korea. Of 15 putative allozyme loci examined 26.7% were polymorphic and expected heterozygosity for the species was low (0.082). Within the range, population were highly differentiated ($F_{ST}$=0.356) and little genetic variation was explained by geography. The pattern of distribution of variation showed low genetic variation within populations and pronounced divergence among populations, which was consistent with the prediction for the effects of limited gene flow and local genetic erosion. Although the frequencies of male plants were dominant ranging from 79.3% to 89.4%, most mating events seems to be inevitable mating between relatives in small populations based on heterozygote deficiency of this species. Small effective population size and the limited dispersal contributed to the low rates of gene flow within as well as between populations.

• Journal of Forest and Environmental Science
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• 제25권3호
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• pp.187-194
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• 2009

This study was carried out to investigate vegetation structure and soil property of natural habitat of Polygonatum stenophyllum to provide basic information for propagation, conservation and restoration. Habitats of Polygonatum stenophyllum were classified into Hemiptelea davidii-Robinia pseudo-acacia dominant population (Yeongwol-eup), Pinus densiflora-Hemiptelea davidii-Callicarpa japonica dominant population (Nam-myeon), and Hemiptelea davidii-Rubus crataegifolius dominant population (Gangchon-ri). The soil pH 6.49~7.28; and electron conductivity 0.10~0.19 ds/m. The average content of organic matter, total nitrogen, available $P_2O_5$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $Na^+$ were 8.24~16.45 g/kg, 0.02~0.13%, 45.67~123.67 mg/kg, 4.61~6.71 cmol(+)/kg, 0.17~0.63 cmol(+)/kg, 0.06~0.27 cmol(+)/kg and 0.03~0.30 cmol(+)/kg, respectively. Species diversity index (H'), maximum species diversity index (H' max), evenness (J') and dominance (1-J') of investigated sites ranged 1.0323 (Nam-myeon)~1.1134 (Yeongwol -eup), 1.4914 (Gangchon-ri)~1.6128 (Nam-myeon), 0.6401 (Nam-myeon)~0.7270 (Yeongwol-eup) and 0.2730 (Yeongwol-eup)~0.3599 (Nam-myeon) respectively.

• 식물분류학회지
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• 제49권4호
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• pp.275-281
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• 2019

One key step in the plant restoration process is the collection of seeds from the field. For the selection of source populations of target plant species for translocation purposes (reintroduction or reinforcements), several approaches are possible. A practical method involves the use of data from reciprocal transplant studies. If no direct data are available, knowledge of population genetics and the phylogeography of the target species can serve as an alternative. In this short review, we briefly propose guidelines for those collecting seeds for plant species restoration based on population genetics theory, focusing on two main questions: Where does the plant material come from and how are sources designated, and how are seeds efficiently collected from local populations? While genetic data on a larger scale (phylogeography and population genetics) are needed to form a reply to the first question, similar data on a smaller scale (fine-scale genetic structures within populations) are necessary to shed light on the second issue.