• ALGAE
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• v.29 no.2
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• pp.153-163
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• 2014

Mesodinium rubrum is a cosmopolitan ciliate that often causes red tides. Predation by heterotrophic protists is a critical factor that affects the population dynamics of red tide species. However, there have been few studies on protistan predators feeding on M. rubrum. To investigate heterotrophic protists grazing on M. rubrum, we tested whether the heterotrophic dinoflagellates Gyrodiniellum shiwhaense, Gyrodinium dominans, Gyrodinium spirale, Luciella masanensis, Oblea rotunda, Oxyrrhis marina, Pfiesteria piscicida, Polykrikos kofoidii, Protoperidinium bipes, and Stoeckeria algicida, and the ciliate Strombidium sp. preyed on M. rubrum. G. dominans, L. masanensis, O. rotunda, P. kofoidii, and Strombidium sp. preyed on M. rubrum. However, only G. dominans had a positive growth feeding on M. rubrum. The growth and ingestion rates of G. dominans on M. rubrum increased rapidly with increasing mean prey concentration < $321ngCmL^{-1}$, but became saturated or slowly at higher concentrations. The maximum growth rate of G. dominans on M. rubrum was $0.48d^{-1}$, while the maximum ingestion rate was 0.55 ng C $predator^{-1}d^{-1}$. The grazing coefficients by G. dominans on populations of M. rubrum were up to $0.236h^{-1}$. Thus, G. dominans may sometimes have a considerable grazing impact on populations of M. rubrum.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.407-407
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• 2019

According to Asian Development Bank report Pakistan is among water scarce countries. Climate scenario on the basis IPCC fifth assessment report (AR5) revealed that annual mean temperature of Pakistan from year 2010-2019 was $17C^o$ which will rise up to $21C^o$ at the end of this century, similarly almost 10% decrease of annual rainfall is expected at the end of the century. It is a changing task in underdeveloped countries like Pakistan to meet the water demands of rapidly increasing population in a changing climate. While many studies have tackled scarcity and stream flow forecasting of the Upper Indus Basin (UIB) Pakistan, very few of them are related to socio-economic and climate change impact on sustainable water management of UIB. This study investigates the pattern of current and future surface water availability for various demand sites (e.g. domestic, agriculture and industrial) under different socio-economic and climate change scenarios in Upper Indus Basin (UIB) Pakistan for a period of 2010 to 2050. A state-of-the-art planning tool Water Evaluation and Planning (WEAP) is used to analyze the dynamics of current and future water demand. The stream flow data of five sub catchment (Astore, Gilgit, Hunza, Shigar and Shoyke) and entire UIB were calibrated and validated for the year of 2006 to 2011 using WEAP. The Nash Sutcliffe coefficient and coefficient of determination is achieved ranging from 0.63 to 0.92. The results indicate that unmet water demand is likely to increase severe threshold and the external driving forces e.g. socio-economic and climate change will create a gap between supply and demand of water.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.248-256
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• 2004

Dendropanax morbifera Lev.(Araliaceae), Korean endemic and evergreen small tree is a component of evergreen forest and mainly distributed in sourthern region and islands in Korea. The ecological characteristics of 4 natural stands of D. morbifera.(Sundol, Suak, Hannam, and Sangho populations in Cheju island) were studied. In most of the D. morbifera natural stands, the following tree species appeared predominantly: Castanopsis cuspidata var. sieboldii, Carpinus laxiflora, D. morbifera, Quercus glauca, Quercus myrsinaefolia, Camellia japonica, and Acer pseudo-sieboldianum. Two tree species, such as C. cuspidata var. sieboldii and C. laxiflora appeared in the all investigated stands. D. morbifera occupied 17.2% of the upper story, 12.9% of the middle story, and 10.3% of the lower story, respectively. The distribution patterns by Morisita' s Index showed that D. morbifera was distributed randomly in the three stories. The frequency distribution of DBH D. morbifera species showed reverse J-shaped, therefore it seems to remain as a dominant species.

• Cross-Cultural Studies
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• v.37
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• pp.7-29
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• 2014

The 'discovery' or 'conquest' of the New World in 1492 was the starting point of world history that irrevocably changed the fate of the Latin American continent. The global stream known as 'Columbian Exchange', which was the widespread inter-continental contacts, inter-civilizational conflicts, or bilateral communication, has rendered multifarious effects throughout many historical periods up to the very contemporary time. The propagation of Catholicism initiated along with this 'discovery' transformed Latin America of nowadays in the region that has the biggest Catholic population in the world. The previous studies in Korea regarding Latin American Catholicism has focused on the spread of Catholicism in relation to the European colonization, rather than analyzing the concrete and detailed ways in which Catholicism exerted tremendous influences in the whole continent. They were less attentive to various historical contexts in which the diffusion of Catholicism differed greatly according to cultural landscapes and political specificities. Thus, this essay attempts to examine the diffusion of Catholicism from the perspective of confrontation between royal authorities and the power of church. The essay points out that the royal communities and institutional authorities which facilitated the intial process of Catholic evangelization maintained antagonistic relationship with ecclesial powers. By delving into the gradual transformation of church systems, it reveals that Catholicism in Latin America became a major field for conquerors in power to attain economic and political dominance. And unlike the initial submission and hospitality, the religious convert of the indigenous people attested to the violent inhumanity and opposition. Therefore, the essay aims to pave a clearer way to the understanding of complicated dynamics and conflicts between Catholicism in Latin America and the establishment of Spanish colonization.

• Journal of Climate Change Research
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• v.8 no.3
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• pp.201-211
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• 2017

This study was conducted to investigate the vascular plants which can be an indicator of environmental change in Seseok of Jirisan National Park. The purpose of this study was to find out the basic information for the subalpine species. This study showed that the area had a total 295 taxa including 63 families, 177 genus, 252 species, 2 subspecies, 36 variants 5 forms and Pte-Q was 1.7. Among them, Korea endemic plants were 15 taxa such as Abies koreana. Rare plants were 14 taxa such as Viola diamantiaca. Naturalized plants consisted of 5 taxa such as Rumex crispus. The floristic regional indicator plants found in surveyed area were 72 taxa comprising 3 taxa of grade V, 7 taxa of grade IV and 24 taxa of grade III. In summary, The subalpine plants of the survey region consisted of 37 taxa including Abies koreana and Gymnadenia cucullata. As rare plants distributed in subalpine zone respond sensitively to climate change, accuracy distribution range, environmental characteristics of habitat and population dynamics of rare plants should be evaluated quantitatively.

• Journal of the Korean Physical Society
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• v.73 no.10
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• pp.1406-1409
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• 2018

We have frequently encountered the rapid changes that prevalent opinion of the social community is toppled by a new and opposite opinion against the pre-exiting one. To understand this interesting process, mean-field model with infinite-interaction range has been mostly considered in previous studies S. A. Marvel et al., Phys. Rev. Lett. 110, 118702 (2012). However, the mean-field interaction range is lack of reality in the sense that any individual cannot interact with all of the others in the community. Based on it, in the present work, we consider a simple model of opinion consensus so-called basic model on the low-dimensional lattices (d = 1, 2) with finite interaction range. The model consists of four types of subpopulations with different opinions: A, B, AB, and the zealot of A denoted by $A_c$, following the basic model shown in the work by S. A. Marvel et al.. Comparing with their work, we consider the finite range of the interaction, and particularly reconstruct the lattice structure by adding new links when the two individuals have the distance < ${\sigma}$. We explore how the interaction range ${\sigma}$ affects the opinion consensus process on the reconstructed lattice structure. We find that the critical fraction of population for $A_c$ required for the opinion consensus on A shows different behaviors in the small and large interaction ranges. Especially, the critical fraction for $A_c$ increases with the size of ${\sigma}$ in the region of small interaction range, which is counter-intuitive: When the interaction range is increased, not only the number of nodes affected by $A_c$ but also that affected by B grows, which is believed to cause the increasing behavior of the critical fraction for $A_c$. We also present the difference of dynamic process to the opinion consensus between the regions of small and large interaction ranges.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.2
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• pp.1-14
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• 2021

It is highly challenging to measure the efficiency of electric vehicle charging stations (EVCSs) because factors affecting operational characteristics of EVCSs are time-varying in practice. For the efficiency measurement, environmental factors around the EVCSs can be considered because such factors affect charging behaviors of electric vehicle drivers, resulting in variations of accessibility and attractiveness for the EVCSs. Considering dynamics of the factors, this paper examines the technical efficiency of 622 electric vehicle charging stations in Seoul using data envelopment analysis (DEA). The DEA is formulated as a multi-period output-oriented constant return to scale model. Five inputs including floating population, number of nearby EVCSs, average distance of nearby EVCSs, traffic volume and traffic congestion are considered and the charging frequency of EVCSs is used as the output. The result of efficiency measurement shows that not many EVCSs has most of charging demand at certain periods of time, while the others are facing with anemic charging demand. Tobit regression analyses show that the traffic congestion negatively affects the efficiency of EVCSs, while the traffic volume and the number of nearby EVCSs are positive factors improving the efficiency around EVCSs. We draw some notable characteristics of efficient EVCSs by comparing means of the inputs related to the groups classified by K-means clustering algorithm. This analysis presents that efficient EVCSs can be generally characterized with the high number of nearby EVCSs and low level of the traffic congestion.

• Journal of Applied Biological Chemistry
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• v.63 no.4
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• pp.429-437
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• 2020

This study aimed to investigate the change in physicochemical properties and lactic acid bacterial communities during kimchi fermentation at different temperatures (8, 15, and 25 ℃) using two molecular genetics approaches, multiplex polymerase chain reaction and 16S rRNA gene sequencing. The pH during fermentation at 8, 15, and 25 ℃ decreased from 6.17 on the initial fermentation day to 3.92, 3.79, and 3.48 after 54, 30, and 24 days of fermentation, respectively, while the acidity increased from 0.24% to 1.12, 1.35, and 1.54%, respectively. In particular, the levels of lactic acid increased from 3.74 g/L on the initial day (day 0) to 14.43, 20.60, and 27.69 g/L during the fermentation after 24, 18, and 12 days at 8, 15, and 25 ℃, respectively, after that the lactic acid concentrations decreased slowly. The predominance of lactic acid bacteria (LAB) in the fermented kimchi was dependent on fermentation stage and temperature: Lactobacillus sakei appeared during the initial stage and Leuconsotoc mesenteroides was observed during the optimum-ripening stage at 8, 15, and 25 ℃. Lac. sakei and Lactobacillus plantarum grew rapidly in kimchi produced at 8, 15, and 25 ℃. In addition, Weissella koreensis first appeared at days 12, 9, and 6 at 8, 15, and 25 ℃ of fermentation, respectively. This result suggests that LAB population dynamics are rather sensitive to environmental conditions, such as pH, acidity, salinity, temperature, and chemical factors including free sugar and organic acids.

• Women's Health Nursing
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• v.27 no.4
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• pp.286-296
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• 2021

Purpose: This study compared infant mortality and its associated factors between Korean and immigrant women using vital statistics gathered by Statistics Korea. Methods: Birth and death statistics from the period between 2009 and 2019 were extracted from the census of population dynamics data of the Microdata Integrated Service, Korea. Statistical data were derived from a complete survey and infant mortality was analyzed from mortality statistics data. Descriptive statistics were used for comparison. Results: The average infant mortality rate (IMR) of Korean women was 2.7 in Korea, which did not change significantly between 2009 and 2019; however, the IMR of immigrant women increased significantly in 2018 to 4.2 and subsequently decreased to 2.6 in 2019. Moreover, the age of Korean and immigrant women at the time of infant death gradually increased from 31.1 years and 25.9 years in 2009 to 32.8 years and 30.9 years in 2019, respectively. The gestational age was lower for deceased infants born to immigrant women (mean, 31.04 weeks; standard deviation [SD], 6.42; median, 30.00) compared to infants born to Korean women (mean, 31.71 weeks; SD, 6.48; median, 32.00). Immigrant women (91.7%) received slightly fewer antenatal care visits compared to Korean women (93.1%). Conclusion: It is vital to devise a plan to lower the IMR of immigrant women in Korea. Moreover, it is necessary to explore the factors related to infant mortality among immigrant women within the context of Korean societal situation, culture, and home environment.

• BMB Reports
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• v.54 no.12
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• pp.592-600
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• 2021

Parkinson's disease (PD) is one of the most common neurodegenerative diseases in the elderly population and is caused by the loss of dopaminergic neurons. PD has been predominantly attributed to mitochondrial dysfunction. The structural alteration of α-synuclein triggers toxic oligomer formation in the neurons, which greatly contributes to PD. In this article, we discuss the role of several familial PD-related proteins, such as α-synuclein, DJ-1, LRRK2, PINK1, and parkin in mitophagy, which entails a selective degradation of mitochondria via autophagy. Defective changes in mitochondrial dynamics and their biochemical and functional interaction induce the formation of toxic α-synuclein-containing protein aggregates in PD. In addition, these gene products play an essential role in ubiquitin proteasome system (UPS)-mediated proteolysis as well as mitophagy. Interestingly, a few deubiquitinating enzymes (DUBs) additionally modulate these two pathways negatively or positively. Based on these findings, we summarize the close relationship between several DUBs and the precise modulation of mitophagy. For example, the USP8, USP10, and USP15, among many DUBs are reported to specifically regulate the K48- or K63-linked de-ubiquitination reactions of several target proteins associated with the mitophagic process, in turn upregulating the mitophagy and protecting neuronal cells from α-synuclein-derived toxicity. In contrast, USP30 inhibits mitophagy by opposing parkin-mediated ubiquitination of target proteins. Furthermore, the association between these changes and PD pathogenesis will be discussed. Taken together, although the functional roles of several PD-related genes have yet to be fully understood, they are substantially associated with mitochondrial quality control as well as UPS. Therefore, a better understanding of their relationship provides valuable therapeutic clues for appropriate management strategies.