• Applied Chemistry for Engineering
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• v.34 no.5
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• pp.541-547
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• 2023

The effect of temperature and influent alkalinity/ammonia (K/A) ratio on the start-up of the partial nitrification (PN) process for an activated sludge-based domestic wastewater treatment was studied. Two different sequence batch reactors (SBR) were operated at 26 ℃ and 32 ℃. The relationship between temperature and the concentration of free ammonia (FA) and free acid nitrite (FNA) was investigated. A stable PN process was achieved in the 32 ℃ reactor when the influent ammonium concentration was lower than 150 mg-N/L. In contrast, the PN process in the 26 ℃ reactor had a higher nitrite accumulation rate (NAR) and ammonium removal efficiency (ARE) when the influent ammonia concentration was increased to more than 150 mg-N/L. Then three different ranges of the K/A ratio were applied to an SBR reactor. In the K/A range of 2.48~1.65, the SBR reactor achieved the highest NAR ratio (75.78%). This ratio helps to achieve the appropriate level of alkalinity to maintain a stable pH and provide a sufficient amount of inorganic carbon source for the activity of microorganisms. At the same time, FA and FNA values also reached the threshold to inhibit nitrite-oxidizing bacteria (NOB) without a significant effect on ammonia-oxidizing bacteria (AOB). Results showed that the control of temperature and K/A ratio during the start-up period may be important in establishing a stable and steady PN process for the treatment of domestic wastewater.

• Korean Journal of Environmental Agriculture
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• v.23 no.1
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• pp.15-21
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• 2004

Objectives of this study were to monitor the distribution of heavy metals, to compare extractable heavy metal with total content and to investigate the relationships between soil physico-chemical properties and heavy metals in orchard soil. Sampling sites were 48 in Gyeonggi, 36 in Gangwon, 36 in Chungbuk, and 44 in Chungnam, Soils were collected farm form two depths, 0 to 20 and 20 to 40 cm (here after referred to as upper and lower layers) from March to May in 1998. Total contents of heavy metal in soils were analyzed by ICP-OES after acid digestion ($HNO_3$:HCl:$H_2O_2$) whereas extractable contents were measured after successive extraction of 0.1N-HCl, 0.05 M-EDTA, and 0.005 M-DTPA. Mercury was analysed by mercury atomizer. The average contents of Cd Cu, and Pb in the extractant with 0.1N-HCl at upper layer were 0.080, 4.23, and 3.42 mg/kg, respectively. As content in the extractant with 1N-HCl was 0.44 mg/kg, and total contents of Zn, Ni and Hg were 78.9, 16.1, and 0.052 mg/kg, respectively. The ratios of concentrations of heavy metals to threshold values (Cd 1.5, Cu 50, Pb 100, Zn 300, Ni 40, Hg 4 mg/ke in Soil Environmental Conservation Act in Korea (2001) were low in the range of $1/2.5{\sim}1/76.9$ in orchard soils. The ratios of extractable heavy metal to total content ranged $5.4{\sim}9.21%$ for Cd, $27.9{\sim}47.8%$ for Cu, $12.6{\sim}21.8$% for Pb, $15.8{\sim}20.3%$ for Zn, $5.3{\sim}6.3%$ for Ni, and $0.7{\sim}3.6%$ for Zn, respectively. Cu and Pb contents in 0.05 M-EDTA extractable solution were higher than those in the other extractable solution. Total contents of Cd, Ni and Ni in soils were negatively correlated with sand content but positively correlated with silt and clay contents. Ratios of extractable heavy metal to total content were negatively correlated with clay content but ai and Ni contents were positively correlated with soil pH, organic matter, and available phosphorous. Therefore, the orchard soil was safe because the heavy metal contents of orchard soil were very low as compared to its threshold value in the Soil Environmental Conservation Act. However, it need to consider the input of agricultural materials to the agricultural land for farming practices for assessment of heavy metals.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.671-676
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• 2005

A total of 50 individual catfish, the Tra (Pangasius hypophthalmus) cultivated in either floating cages (Tra-c) or in ponds (Tra-p) and the Basa (Pangasius bocourti) raised in three floating cages, were collected in two of the Mekong Delta provinces. The caudal fin of each individual fish was used for protein electrophoresis employing the SDS-PAGE method. The one fillet sides were used as a representative sample to determine the dry matter (DM), crude protein (CP), ether extract (EE) and amino acids (AAs). The catfish oil was extracted from the belly fats, and the fatty acid (FA) composition was analyzed. There were 21 bands of the Tra and the Basa. Protein bands of the two varieties were 28.6-33.3% polymorphic, while polymorphic individuals of the Tra ranged from 80.0 to 100.0%, and the Basa was 90.0% polymorphic. The phenotypic diversity (Ho) of the Tra ranged from 1.71 to 1.80, while the Basa ranged as high as 2.14%. Diversity values (H$_{EP}$) for genetic diversity markers were equal in the Tra and the Basa. The sum of the effective number of alleles (SENA) of both varieties ranged from 3.40 to 3.83 for the Basa and the Tra, respectively. The lower values of Ho and SENA, as compared with those of the fresh water prawn (Macrobrachium equidens) in the area, would suggest that the species with the low values will become extinct due to inbreeding; the gene pools of each observed population were below a suitable threshold. Many of the differences in the nutritional values of the Tra-c, the Tra-p and the Basa were measured; their nutrient values were comparable to fishmeal or fish oil. Most of the DM, CP, and EE were higher in the Tra, especially in the Tra-c. The essential AA content, especially that of lysine, was highest in the Tra-c, next highest in the Tra-p, and lowest in the Basa. Therefore, the amino acid patterns were closer to the ideal patterns in the same sequences. In contrast, the essential FAs were concentrated in the Basa fish oil. It was found that suitable selection of parents for seed production is required to avoid inbreeding. Catfish may be valuable sources of nutrition for both humans and animals, and the differences in their nutritional values by variety and/or management must be taken into account.

• Journal of fish pathology
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• v.4 no.2
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• pp.71-77
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• 1991

From August to October of 1991, a bacterial disease occurred in cultured flounder, of 0 age Paralichthys olivaceus, in Cheju-do. Typical symptoms of the diseased fish were the hemorrage of the opercle, discoloration of the body, exophthalmus and hemorrhage of the eyes. The causative organism isolated from diseased fish was identified as a $\beta$-hemolytic Streptococcus. This bacterium was not identical with any known Streptococcus species listed in Bergey's Manual of Determinative Bacteriology 8th edition. However there was a close similarity between this species and Streptococcus sp. isolated from flounder and reported by Tashio (1983). The isolated bacteria streptococcus sp. showed very high sensitivity to the SM and EM, however, it resisted to the high concentration of Penicillin. In the pathagenicity analysis, about $1.1{\times}10^9$, $1.1{\times}10^7$, $1.1{\times}10^5$, $1.1{\times}10^3$, $1.1{\times}10^1cells$/100g B.W of isolated bacteria were injected percutaneouly. The results showed that this inoculation size $1.1{\times}10^3cells$/100g B.W was the threshold for the induction of mortality in pathogenicity analysis.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11a
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• pp.65-68
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• 2003

본 논문에서는 가장 최근의 동영상 표준인 H.264에서 가변 블록 움직임 예측 시 인접한 블록과의 상관성을 분석하여 병합 절차를 추가함으로써 매크로블록의 최종 모드를 결정하는 시간을 줄이기 위한 알고리즘을 제안한다. H.264에서는 매크로블록의 모드를 결정하기 위하여 총 7가지 모드를 사용하여 움직임 예측은 실시함으로써 부호화 효율을 극대화시킨 반면 이러한 움직임 예측이 부호화기의 복잡도를 높이는 주요 요인으로 현재 커다란 단점으로 지적되고 있다. 본 논문에서는 $8{\times}8$ 움직임 예측이 끝난 후 인접한 두 블록 사이의 거리론 임계값(Threshold)과 비교하여 다음 모드의 움직임 예측의 실시 여부를 먼저 절정함으로써 필요한 움직임 예측에 소비되는 시간을 단축시켰다. 여기서 실험 조건으로 명시하고 있는 것은 대표적인 단일모드 중에서 수행 성능이 가장 좋은 $8{\times}8$ 모드를 기본모드로 사용하고 병합 시 $16{\times}16$ 모드 쪽으로 상향식(bottom-up) 방법의 병합을 수행해 나아간다 모의실험을 통해 수행 성능과 전체 부호화 시간 측면을 본 논문에서 제안한 방법과 4가지 모드인 $16{\times}16,\;16{\times}8,\;8{\times}16,\;8{\times}8$ 모드를 모두 사용한 경우, $8{\times}8$ 단일모드를 사용한 경우를 비교하였다. 실험 결과 $8{\times}8$ 단일모드보다 수행 성능이 향상되었으며, 시간 단축 면에서 제안한 방법이 4가지 모드인 $16{\times}16,\;16{\times}8,\;8{\times}16,\;8{\times}8$ 모드를 모두 사용한 경우와 $8{\times}8$ 단일모드를 사용한 경우보다 계산 시간이 감소하였음을 확인하였다.행중인 MoIM-Messge서버의 네트워크 모듈로 다중 쓰레드 소켓폴링 모델을 적용하였다.n rate compared with conventional face recognition algorithms. 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타나며 그 유의성이 움직임 보정 전에 비하여 낮음을 알 수 있었다. 결론: 뇌활성화 과제 수행시에 동반되는 피험자의 머리 움직임에 의하여 도파민 유리가 과대평가되었으며 이는 이 연구에서 제안한 영상정합을 이용한 움직임 보정기법에 의해서 개선되었다. 답이 없는 문제, 문제 만들기, 일반화가 가능한 문제 등으로 보고, 수학적 창의성 중 특히 확산적 사고에 초점을 맞추어 개방형 문제가 확산적 사고의 요소인 유창성, 독창성, 유연성 등에 각각 어떤 영향을 미치는지 20주의 프로그램을 개발, 진행하여 그 효과를 검증하고자 한다. 개방형 문

• Maxillofacial Plastic and Reconstructive Surgery
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• v.40
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• pp.44.1-44.17
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• 2018

Background: Coffee extract has been investigated by many authors, and many minor components of coffee are known, such as polyphenols, diterpenes (kahweol and cafestol), melanoidins, and trigonelline, to have anti-inflammatory, anti-oxidant, anti-angiogenic, anticancer, chemoprotective, and hepatoprotective effects. Therefore, it is necessary to know its pharmacological effect on hepatocytes which show the most active cellular regeneration in body. Methods: In order to determine whether coffee extract has a beneficial effect on the liver, 20 C57BL/6J mice were intraperitoneally injected once with dialyzed coffee extract (DCE)-2.5 (equivalent to 2.5 cups of coffee a day in man), DCE-5, or DCE-10, or normal saline (control), and then followed by histological observation and IP-HPLC (immunoprecipitation high performance liquid chromatography) over 24 h. Results: Mice treated with DCE-2.5 or DCE-5 showed markedly hypertrophic hepatocytes with eosinophilic cytoplasms, while those treated with DCE-10 showed slightly hypertrophic hepatocytes, which were well aligned in hepatic cords with increased sinusoidal spaces. DCE induced the upregulations of cellular proliferation, growth factor/RAS signaling, cellular protection, p53-mediated apoptosis, angiogenesis, and antioxidant and protection-related proteins, and the downregulations of NFkB signaling proteins, inflammatory proteins, and oncogenic proteins in mouse livers. These protein expression changes induced by DCE were usually limited to the range ± 10%, suggesting murine hepatocytes were safely reactive to DCE within the threshold of physiological homeostasis. DCE-2.5 and DCE-5 induced relatively mild dose-dependent changes in protein expressions for cellular regeneration and de novo angiogenesis as compared with non-treated controls, whereas DCE-10 induced fluctuations in protein expressions. Conclusion: These observations suggested that DCE-2.5 and DCE-5 were safer and more beneficial to murine hepatocytes than DCE-10. It was also found that murine hepatocytes treated with DCE showed mild p53-mediated apoptosis, followed by cellular proliferation and growth devoid of fibrosis signaling (as determined by IP-HPLC), and subsequently progressed to rapid cellular regeneration and wound healing in the absence of any inflammatory reaction based on histologic observations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.725-730
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• 2017

The strength ratio of the main structures of buildings gradually increasing, due to the advances made in analysis and cost saving techniques. In this study, to examine the stability of industry buildings using sandwich panels as roof assemblies, we examine the changes in the moment strength ratio of the main structures caused by increasing the roof load. This study adopts the PEB structure and three H-steel structure as the structural analysis models. In the case where the additional load exceeds about 11% of the roof design load, the strength ratio exceeds 1 for the main structure. In the case where the additional load exceeds about 36%(of the roof design load), the working moment exceeds the plastic moments, which leads to major damage to the structure. This study compares 1) the maximum load according to the purlin spaces, 2) the maximum load by KS, and 3) the maximum load calculated from the test results of the manufacturer.The maximum bearing load of the panels determined by all three methods exceeds the structure failure threshold load of the main structure. This study provides evidence that an unexpected increase in the roof load might cause the whole structure to collapse, due to the failure of the main structural members, before the failure of the roof assemblies. Therefore, information on the structural performance of the sandwich panels is required for the structural design, and the sandwich panels should be considered to be an integral part of the overall structural design.

• Journal of Microbiology and Biotechnology
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• v.33 no.10
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• pp.1292-1298
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• 2023

PAMB 00755^T, a bacterial strain, was isolated from Korean fir leaves. The strain exhibits yellow colonies and consists of Gram-negative, non-motile, short rods or ovoid-shaped cells. It displays optimal growth conditions at 20℃, 0% NaCl, and pH 6.0. Results of 16S rRNA gene-based phylogenetic analyses showed that strain PAMB 00755^T was most closely related to Sphingomonas chungangi MAH-6^T (97.7%) and Sphingomonas polyaromaticivorans B2-7^T (97.4%), and ≤96.5% sequence similarity to other members of the genus Sphingomonas. The values of average nucleotide identity (79.9-81.3%), average amino acid identity (73.3-75.9%), and digital DNA-DNA hybridization (73.3-75.9%) were significantly lower than the threshold values for species boundaries; these overall genome-related indexes (OGRI) analyses indicated that the strain represents a novel species. Genomic analysis revealed that the strain has a 4.4-Mbp genome encoding 4,083 functional genes, while the DNA G+C content of the whole genome is 66.1%. The genome of strain PAMB 00755^T showed a putative carotenoid biosynthetic cluster responsible for its antioxidant activity. The respiratory quinone was identified as ubiquinone 10 (Q-10), while the major fatty acids in the profile were identified as C_18:1ω7c and/or C_18:1ω6c (summed feature 8). The major polar lipids of strain PAMB 00755^T were diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, and phosphatidylcholine. Based on a comprehensive analysis of genomic, phenotypic, and chemotaxonomic characteristics, we proposed the name Sphingomonas abietis sp. nov. for this novel species, with PAMB 00755^T as the type strain (= KCTC 92781^T = GDMCC 1.3779^T).

• Tuberculosis and Respiratory Diseases
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• v.44 no.1
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• pp.154-161
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• 1997

Background : Although the long term adverse effects of cigarette smoking on health are well known, the acute possible detrimental effects of smoking on pulmonary or cardiovascular function, especially when these systems are stressed by the metabolic demands of exercise, have not been well studied The purpose of this study is to determine the acute action of cigarette smoking on cardiopulmonary function under stress. Method : Twenty -one healthy smoking subjects were studied. Before exrecise testing, history taking, physical examination and baseline studies, including CBC, chest PA, PFT and EKG, were done. The subjects performed an incremental bicycle exercise test to exhaustion on two occasions, one without smoking and the other after smoking 5 cigarettes/h for 2 hours. All indices of P.F.T. and bicycle ergometry were compared between before and after smoking. Results : 1. $VO_2$max and $O_2$ pulse showed significant decrease in smoking day. 2. Although there were no significant differences, anaerobic threshold showed a tendency of decrease and HRmax showed that of increase in smoking day. 3. P.F.T. and respiratory indices showed no significant change io smoking day. Conclusion : Cigarette smoking has immediate adverse effect, especially on the cardiovascular system rather than the respiratory system. These results would be due to the effect of elevated HbCO and/or impaired blood flow in response to the exercise stimulus.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.93-101
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• 2000

Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.