• Korean Journal of Poultry Science
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• v.48 no.4
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• pp.207-216
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• 2021

This study was conducted to determine the nutritional quality of two newly-developed native chicken strains, compared to the commercial Korean native chicken. A total of 600 chickens (CON: Hanhyup No. 3, CL1: candidate line C, CL2: candidate line D) raised under the same conditions were slaughtered at either 5 or 12 weeks. Leg meat was then obtained and analyzed for its physicochemical properties. The results showed that regardless of the growing period, there was no variation in proximate composition (P>0.05), except for crude protein, between strains. Water holding capacity did not differ between strains at either slaughter age; however, it was significantly lower in the 12-week group than in the 5-week group (P≤0.05). For both skin and muscle color, a^* and b^* values were lower at 12 weeks than at 5 weeks (P≤0.05). DPPH radical-scavenging activity tended to be lower at 12 weeks than at 5 weeks (P≤0.05). Furthermore, all chickens slaughtered at 5 weeks were found to have greater contents of linoleic acid (18:2) and polyunsaturated fatty acids (PUFA) and lower atherogenicity and thrombogenicity indices than those slaughtered at 12 weeks (P≤0.05). However, anserine, betaine, and glucose were more concentrated among the lines at 12 weeks than at 5 weeks (P≤0.05). In conclusion, the quality traits of native chickens were distinct by different production stages rather than chicken lines.

• Korean Journal of Environment and Ecology
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• v.35 no.6
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• pp.621-631
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• 2021

The purpose of this study is to survey and analyze acorn production and characteristics of the Quercus acuta Thunb. according to the need for information on seed supply and seedling cultivation during the restoration of warm broad-leaved forests. For the survey, a total of 30 seed traps with a surface area of 1 m² were set up, 3 in each of 10 quadrats (8 in Wando, 1 in Haenam, and 1 in Jindo). The acorns that fell in the seed trap at the end of each month were collected from August to December each year between 2013 to 2016. The collected acorns were then classified into sound, damaged, decayed, or empty grade, and the number of acorns produced was calculated. In the case of sound acorns, acorn traits, such as length, diameter and weight of acorns without cupule, were measured. Duncan's multiple tests of acorn production and characteristics were conducted for comparative analysis of the annual average values with the values by year, stand, month, and treatment plot. The annual number of acorn dropped into the seed traps in each quadrat from 2013 to 2016 was 5-350 acorns/3 m² in 2013, 17-551 acorns/3 m² in 2014, 5-454 acorns/3 m² in 2015, and 14-705 acorns/3 m² in 2016. There was a large difference in acorn production between the quadrats, presumably attributed to the difference in the amount of light received due to the density of trees in the square. Annual acorn production per area was 335,000 acorns/ha in 2013, 932,000 acorns/ha in 2014, 556,000 acorns/ha in 2015, and 1,037,000 acorns/ha in 2016. That was a sharp variation of acorn production in the two-year cycle. As the fluctuation in the production of Q. acuta showed simultaneity between stands, it is judged that Quercus acuta Thunb. had a clear cycle of fruitfulness and fruitiness between forest objects. September showed the biggest amount of fallen acorns and largest damage from insect pests, indicating that preventing early fall of acorns could increase the fruiting period and enable mass production of sound acorns. There was no significant difference between annual average acorn length in each region. In the case of the acorn diameter and weight, the average values of acorns from Haenam were significantly higher than those from Wando and Jindo. There was no significant difference in the average annual acorn characteristics by month, and the average annual acorn length, diameter, and weight in November were 19.72mm, 12.23mm, and 1.64g, respectively, the highest between August and November.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.1-17
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• 2023

Purpose. The purpose of this study was to examine the correlation between the finish line designs and the marginal adaptation of nonprecious metal alloy coping produced by different digital manufacturing methods. Materials and methods. Nonprecious metal alloy copings were made respectively from each master model with three different methods; SLS, milling and casting by computer aided design and computer aided manufacturing (CAD-CAM). Twelve copings were made by each method resulting in 72 copings in total. The measurement was conducted at 40 determined reference points along the circumferential margin with the confocal laser scanning microscope at magnification ×150. Results. Mean values of marginal gap of laser sintered copings were 11.8 ± 7.4 ㎛ for deep chamfer margin and 6.3 ± 3.5 ㎛ for rounded shoulder margin and the difference between them was statistically significant (P < .0001). Mean values of marginal gap of casted copings were 18.8 ± 20.2 ㎛ for deep chamfer margin and 33 ± 20.5 ㎛ for rounded shoulder margin and the difference between them was significant (P = .0004). Conclusion. Within the limitation of this study, the following conclusions were drawn. 1. The variation of finish line design influences the marginal adaptation of laser sintered metal coping and casted metal coping. 2. Laser sintered copings with rounded shoulder margin had better marginal fit than deep chamfer margin. 3. Casted copings with deep chamfer margin had better marginal fit than rounded shoulder margin. 4. According to the manufacturing method, SLS system showed the best marginal fit among three different methods. Casting and milling method followed that in order.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.2
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• pp.239-247
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• 2023

The FIDIC Red Book is an international standard contract condition in which the Employer designs and the Contractor performs the construction. The Engineer of FIDIC Red Book shall agree or determine any matter or Claim in accordance with Sub-Clause 3.7 neutrally, not as an agent of the Employer. This study aimed to derive Key Risk Sub-Clauses out of 49 Sub-Clauses that the Engineer of FIDIC Red Book recently revised in 18 years shall agree or determine according to Sub-Clause 3.7 using the Delphi method. A panel of 35 experts with more than 10 years of experience and expertise in international construction contracts was formed, and through total three Delphi surveys, errors and biases were prevented in the judgment process to improve reliability. As for the research method, 49 Sub-Clauses that engineers shall agree on or determine according to Sub-Clause 3.7 of the FIDIC Red Book were investigated through the analysis of contract conditions. In order to evaluate the probability and impact of contractual risk for each 49 Sub-Clause, the Delphi survey conducted repeatedly a closed-type survey three times on a Likert 10-point scale. The results of the first Delphi survey were delivered during the second survey, and the results of the second survey were delivered to the third survey, which was re-evaluated in the direction of increasing the consensus of experts' opinions. The reliability of the Delphi 3rd survey results was verified with the COV value of the coefficient of variation. The PI Risk Matrix was applied to the average value of risk probability and impact of each of the 49 Sub-Clauses and finally, 9 Key Risk Sub-Clauses that fell within the extreme risk range were derived.

• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.125-137
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• 2022

To assess the characteristics of meiofaunal community fluctuations related to environmental factors, seasonal surveys were conducted in the subtidal zone of Hallyeohaesang National Park. The average depth of the study area was about 20 m, and the average water temperature at the bottom was low in winter(11.33℃) and high in summer(17.95℃). The sedimentary particles mainly comprised silt and clay at most stations. The abundance of meiofauna ranged from 81.7 to 1,296.5 Inds. 10 cm^-2, and the average abundance was 589.3 Inds. 10 cm^-2. The average abundance of meiofauna in each season was the lowest at 416.5 Inds. 10cm^-2 in winter and the highest at 704.5Inds.10 cm^-2 in spring. The dominant taxa were nematodes (about 92%) and harpacticoids (about 5%). In the cluster analysis of meiofaunal communities, they were divided into four significant groups. The largest group mainly contained spring and summer samples, and contained stations with a high nematode density of over 500 Inds. 10 cm^-2 and harpacticoids below 50 Inds. 10 cm^-2 with a high composition ratio of nematodes. In the cluster analysis, no regional division was found between the stations, and it was thought to be divided by the seasons with high abundance according to seasonal variation and the composition ratio of nematodes and harpacticoids. In the Spearman rank correlation analysis, the density of total meiofauna and the most dominant taxa, nematodes, was not significantly related to environmental factors. However, the density of harpacticoids had a significant positive correlation with water depth and a negative correlation with sediment particle size.

• Journal of Korean Society of Forest Science
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• v.112 no.2
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• pp.127-135
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• 2023

This study aimed to develop biomass allometric equations and estimate carbon emission factors, such as the wood density, biomass-expansion factor, and root-to-shoot ratio, for Platanus occidentalis and Metasequoia glyptostroboides planted in urban areas. Twenty M. glyptostroboides and 25 P. occidentalis trees were harvested, and the dry weights and stem volumes of stems, branches, leaves, and roots (>5 mm) were measured. The wood densities of M. glyptostroboides and P. occidentalis were 0.293 ± 0.008 g cm^-3 and 0.509 ± 0.018 g cm^-3, and the biomass-expansion factors were 1.738 ± 0.031 and 1.561 ± 0.035. The root-to-shoot ratios were 0.446 ± 0.009 and 0.402 ± 0.012. The uncertainty tests (coefficient of variation, %) gave 2.8% and 3.5% values for wood density, 1.8% and 2.3% for biomass-expansion factor, and 2.1% and 2.9% for root-to-shoot ratio, respectively. Among the developed allometric equations, Model I using the diameter at breast height (DBH) was suitable. The allometric equations of M. glyptostroboides and P. occidentalis above ground were y = 1.679 (DBH)^1.315 and y = 0.505 (DBH)^1.896, and the allometric equations of the root and total were y = 0.746 (DBH)^1.315, y = 0.301 (DBH)^1.751, y = 2.422 (DBH)^1.316, and y = 0.787 (DBH)^1.858. If the carbon-emission factors of this study and biomass allometric equations of the three developed models are used to estimate the carbon storage and biomass of urban forests, errors caused by not considering the use of fixed factors and the environmental differences can be reduced.

• Health Policy and Management
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• v.34 no.2
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• pp.185-195
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• 2024

Background: Disabled people have particularly restricted access to health care. In response to this, the pilot project for the general physician (GP) system for disabled people was implemented in 2018, based on the rights of people with disability to the Health Act in South Korea. However, its participants were 0.2% among the total of those with severe disabilities in 2021. Therefore, this study examined the factors related to registering with a GP and the access level to its services to suggest implications for activating the participation of disabled people. Methods: We analyzed factors affecting the registration with a GP and the number of using the services among the participants of the GP system during May 2018 and December 2021 by conducting hierarchical logistic regression and hierarchical regression. The data were linked with the national health insurance data to examine various predictors, including disability types, socioeconomic status, health status, and GP registration. Results: As a result of analyzing the factors affecting whether or not to register for the pilot project, those with disabilities (physical disabilities, brain lesions, visual, intellectual, mental, and autistic disability) eligible for disability care (odds ratio [OR], 4.157) than other disability, and those living in metropolitan (OR, 4.330) or cities (OR, 3.332) than rural residences were highly likely to enroll the pilot study. Health-related variables also predicted the registration status of the pilot project. The predictors related to GP enrollment types (membership type: general health or disability care, GP's affiliation: clinics or hospitals) significantly influenced levels of access to services. Conclusion: It is necessary to develop the GP project for disabled people by considering the variation in types of disability, residences, and health. Further study will be needed to investigate the impact of GPs on the level of participation among disabled people.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.4
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• pp.213-228
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• 2009

This study was conducted to investigate spatio-temporal changes in macrobenthic community structure and benthic environmental conditions in Geoje-Hansa Bay, which is the greatest oyster producing site in Korea. Field survey for benthic environment and macrobenthos was seasonally carried out at 15 stations covering oyster farming sites and non-farming sites from February to November, 2008. The grain size of surface sediments was dominated by very fine silt with the mean phi of about $9\;{\Phi}$ and TOC was 1.9% on average. Mean dissolved oxygen content was 8.1 mg/L and lowest in August corresponding to the 2nd degree in seawater quality criteria. Total species number was 351 and mean density was $3,675\;ind./m^2$, both of which were dominated by polychaete worms. Spatio-temporal variation in above two biological variables was great with higher values seasonally in spring and spatially in channels rather than inner bay. Dominant species were Lumbrineris longifolia (21.3%), Aphelochaeta monilaris (17.8%) and Ericthonius pugnax(6.1%), all of which are typical species of organically enriched area. From the multivariate analyses, the whole macrobenthic community was distinguished into two groups of channel and inner bay group. Spatio-temporal changes of macrobenthic community in Geoje-Hansan Bay were related to those of TOC and acid volatile sulfide (AVS). Our results showed that Geoje-Hansan Bay should be intermediately affected by organic pollution, and that such organic enrichment was more remarkable at farming stations in the inner bay.

• Research in Plant Disease
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• v.29 no.4
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• pp.345-362
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• 2023

Anthracnose, caused by the Colletotrichum genus, comprises a significant number of plant pathogens and poses a major threat to fruit production worldwide, including South Korea. Colletotrichum species were identified associated with anthracnose in fruits such as apple, persimmon, plum, peach, jujube, walnut, and grape. A polyphasic approach, including morphology, multigene phylogenetics, and pathogenicity testing, was used. Additionally, the in-vitro sensitivity of identified Colletotrichum species to common fungicides was also evaluated. A total of nine Colletotrichum species within two complexes, namely gloeosporioides and acutatum, have been identified as the causal agents of anthracnose in common fruits in South Korea. In the gloeosporioides complex, we found Colletotrichumaenigma, C. fructicola, C. gloeosporioides, C. horii, C. siamense, and C. viniferum. Meanwhile, in the acutatum complex, C. fioriniae, C. nymphaeae, and C. orientalis were identified. Notably, C. fructicola, C. siamense, C. fioriniae, and C. nymphaeae were reported for the first time from apple, C. siamense, C. fioriniae and C. nymphaeae from plum, C. siamense, C. fructicola, and C. fioriniae frompeach, C. siamense and C. horii from persimmon, C. fioriniae from Omija (Schisandra), C. orientalis from walnut, C. nymphaeae from jujube, and C. aenigma, C. fructicola, and C. siamense fromgrape. Fungicide sensitivity tests revealed significant variation in the EC₅₀ values among specific Colletotrichum species when exposed to different fungicides. Moreover, the same Colletotrichum species isolated from different host plants displayed varying sensitivity to the same fungicide.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.345-363
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• 2023

The genus Desmodesmus (Chodat) S.S. An, T. Friedl & E. Hegewald is ubiquitous in freshwater ecosystems, such as rivers, ponds, and wetlands. The actual species diversity and distribution of the genus is unknown because of morphological plasticity affected by habitats. Currently, 38 Desmodesmus species have been reported in Korea most of which transferred from the genus Scenedesmus recently, however, no phylogenetic relationships have been studied yet. Despite the challenges in analyzing relationships among Desmodesmus species through the morphology, ecology, and original description, this study focused on examining species-level relationships using the FBCC culture strains isolated from Korea. A total of 299 sequences (66 of 18S rRNA, 47 of atpB, 67 of petA, 52 of rbcL, and 67 of tufA) were newly determined and used for phylogenetic analysis. Four plastid genes tend to have higher variation than 18S rRNA in the variable sites and P-distance. From the combined phylogeny, the Desmodesmus included six clades such as Clade-1: D. pseudoserratus and D. serratus, Clade-2: D. communis, D. dispar, D. maximus, D. pannonicus, unidentified Desmodesmus sp., Clade-3: D. bicaudatus and D. intermedius, Clade-4: D. microspina, D. multivariablis, D. pleiomorphus, D. subspicatus, Clade-5: D. abundans, D. kissii, and D. spinosus, and Clade-6: D. armatus, D. armatus var. longispina, D. opoliensis, unidentified Desmodesmus spp. The new sequence data from FBCC strains will be used to identify species and study the molecular ecology of scenedesmacean green algae in freshwater ecosystems. The phylogenetic information from this study will expand our understanding of Desmodesmus species diversity in Korea.