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Ammonia Wastewater Treatment and Selective Recovery Using a Sweep Gas-Vacuum Hybrid Type Membrane Degassing Process (스윕 가스-진공 하이브리드식 탈기막 공정을 활용한 암모니아 폐수처리 및 선택적 회수)

  • Hongsik Yoon;Taijin Min;Minkyu Jeon;Sungil Lim;Sechul Oh;Kyungha Ryu;Chungsung Lee;Bosik Kang
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.6_2
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    • pp.1171-1181
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    • 2023
  • In this study, a sweep gas - vacuum hybrid type membrane degassing process was proposed for ammonia wastewater treatment. In addition, the ammonia selective recovery of the hybrid type membrane degassing process was also investigated. As a result, the hybrid type membrane degassing process showed better degassing performance (54.9 mg NH3/m2min for 360 min) than the sweep gas type (32.3 mg NH3/m2min) or vacuum type (22 mg NH3/m2min). Additionally, the hybrid type membrane degassing process showed an excellent ammonia selectivity (103 times compared to Na+ Na+, 133 times compared to Ca2+). The ammonia selectivity was appeared to be due to the conversion characteristics of ammonium ion / dissolved ammonia depending on pH. The results in this study are expected to be used in the development of ammonia wastewater treatment and ammonia recovery in the future.

First Record of Four Yeast Strains Isolated from Freshwater in Korea (국내 담수환경에서 분리된 국내 미기록 효모 4종 보고)

  • Yoosun Oh;Wonsu Cheon;Hye Yeon Mun;Jaeduk Goh
    • The Korean Journal of Mycology
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    • v.51 no.4
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    • pp.349-359
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    • 2023
  • Freshwater ecosystems are significant habitats of fungi including yeasts. This study aimed to isolate and characterize wild yeasts from freshwater environments in Korea. The yeast isolates were identified by using the D1/D2 domains of the 26S rDNA regions. We identified four strains, Candida viswanathii (NNIBRFG39781), Curvibasidium cygneicollum (NNIBRFG49003), Oberwinklerozyma silvestris (NNIBRFG39803) and Vishniacozyma foliicola (NNIBRFG6120). These yeasts had not previously been recorded in Korea. We investigated the morphological and cultural characteristics of these yeasts. All of them grew on YPD, PD and YM media. Candida viswanathii (NNIBRFG39781), O. silvestris (NNIBRFG39803) and V. foliicola (NNIBRFG6120) grew in YPD medium containing glucose and in pH range of 4-8. Curvibasidium cygneicollum (NNIBRFG49003) grew well low temperature compared to others and slowly.

Quality Characteristics and Functionality of Rose Sparkling Wines by Secondary Fermentation (2차 발효 후 로제 스파클링 와인의 품질 특성 및 기능성)

  • Hyerim Shin;YunJeong Lee;On Bit Hwang;Eui Kwang Park;Sungyeol Choi;Dong Kyu Yoon;Hyang-Sik Yoon
    • The Korean Journal of Food And Nutrition
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    • v.36 no.6
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    • pp.425-435
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    • 2023
  • This study investigated quality characteristics and functionality of rose sparkling wine that were manufactured by secondary fermentation after inoculation of yeast strains. The pH of the samples ranged from 3.96 to 4.05 and total acidity ranged from 0.23 to 0.32%. The alcohol contents of wines ranged from 6.4 to 6.6% and the CO2 pressure ranged from 2.0 to 2.6 bar. The brightness of rose wines ranged from 84.72 to 87.36, the redness from 9.28 to 14.15, and the yellowness from 9.50 to 19.20. The hue value of wines ranged from 1.137 to 1.513 and color intensity ranged from 0.724 to 0.882. Aroma analysis identified 14 alcohols, 22 esters, 4 ketones, 4 acids, and 17 miscellaneous compounds. The total tannin contents and total polyphenol contents of wines were 11.28~12.43 mg% and 24.79~28.20 mg%, respectively. The DPPH radical scavenging activity of wines ranged 63.33 to 67.89% and the ABTS radical scavenging activity of wines 82.16~86.06%. The results of this study provide a basis for establishing the brewing process of rose sparkling wines yeast strains.

Effects of whole-plant corn and hairy vetch (Vicia villosa Roth) mixture on silage quality and microbial communities

  • Yaqian Zong;Kai Zhou;Xinhui Duan;Bo Han;Hua Jiang;Chenggang He
    • Animal Bioscience
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    • v.36 no.12
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    • pp.1842-1852
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    • 2023
  • Objective: Hairy vetch is considered to improve the nutritional value of corn because of its high protein and mineral levels. To better understand the mechanism underlying hairy vetch regulated whole-plant corn silage fermentation, this experiment investigated the fermentation quality and bacterial community of whole-plant corn and hairy vetch mixture. Methods: Whole-plant corn and hairy vetch were mixed at ratios of 10:0 (Mix 10:0), 8:2 (Mix 8:2), 6:4 (Mix 6:4), 4:6 (Mix 4:6), 2:8 (Mix 2:8), and 0:10 (Mix 0:10) on a fresh weight basis. After ensiling 60 days, samples were collected to examine the fermentation dynamics, ensiling characteristics, and bacterial communities. Results: Mix 0:10, Mix 2:8, and Mix 4:6 showed poor fermentation characteristics. Mix 8:2 and Mix 6:4 silages showed high quality, based on the low pH, acetic acid, and ammonia nitrogen levels and the high lactic acid, crude protein, and crude fat contents. The bacterial diversity was affected by the mixing ratio of the two forage species. The genus Lactobacillus dominated the bacterial community in Mix 10:0 silage, whereas with the addition of hairy vetch, the relative abundance of unclassified-Enterobacter increased from 7.67% to 41.84%, and the abundance of Lactobacillus decreased from 50.66% to 13.76%. Conclusion: The silage quality of whole-plant corn can be improved with inclusion levels of hairy vetch from 20% to 40%.

Association between diet quality and untreated dental caries: results from the Korea National Health and Nutrition Examination Survey

  • Seon-Ju Sim;Ja-Young Moon;Hye-Sun Shin
    • Nutrition Research and Practice
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    • v.17 no.5
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    • pp.959-968
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    • 2023
  • BACKGROUND/OBJECTIVES: Few studies have provided evidence of the association between diet quality and dental caries. This study aimed to examine the association between diet quality and untreated dental caries in a Korean representative population. SUBJECTS/METHODS: The study population included a sample of 13,815 participants, aged ≥ 19 from the Korea National Health and Nutrition Examination Survey during 2013-2015. The explanatory variable was diet quality and the outcome variable was untreated dental caries. Untreated dental caries were defined by the number of decayed teeth recorded according to the criteria established by the World Health Organization. Diet quality was defined by using the Korean Healthy Eating Index (KHEI) through the 24-h recall methods. We assessed the association between diet quality and untreated dental caries while adjusting for age, sex, education, income, smoking status, dental visits, toothbrushing frequencies, obesity, and diabetes mellitus. RESULTS: The mean overall KHEI scores in the untreated dental caries group were significantly lower than those in the group without untreated dental caries. Significant differences were observed in the untreated dental caries group based on the KHEI quartiles (P < 0.001). After adjusting for potential confounders, the quartiles of KHEI scores showed an association with untreated dental caries, demonstrating a dose-effect trend (odds ratio [OR], 1.57; 95% confidence interval [CI], 1.35-1.84 for 1st quartile; OR, 1.38; 95% CI, 1.19-1.59 for 2nd quartile; OR, 1.32; 95% CI, 1.14-1.53 for 3rd quartile; reference quartile highest]). CONCLUSIONS: The findings indicated an inverse association between diet quality and untreated dental caries in Korean adults. Healthcare providers should take into account the significant role of diet quality in preventing and managing oral health.

Effects of different stocking density in lairage of fattening pigs in high temperatures

  • Dongcheol Song;Seyeon Chang;Jaewoo An;Sehyun Park;Kyeongho Jeon;Hyuck Kim;Jinho Cho
    • Korean Journal of Agricultural Science
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    • v.50 no.4
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    • pp.861-867
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    • 2023
  • Lairages serve several functions, such as providing post-mortal inspections and providing a reservoir of animals to ensure the slaughter line runs efficiently. High stress lairage conditions can contribute to the accumulation of transport stress in pigs, causing poor pork quality and still stressed pigs at slaughter. The objective of this study was to investigate meat quality, blood profile and behavior changes according to lairage stocking density in in high temperature. Density treatments were as follows: LD, low density (lower than 0.5 m2/100 kg); ND, normal density (0.5 m2/100 kg to 0.83 m2/100 kg); HD, high density (higher than 0.83 m2/100 kg). Air temperature treatment was as follows: HT, high temperature (higher than 24℃). Pigs stocked with LD showed lower pH, WHC (water holding capacity), and higher DL (drip loss) and CL (cooking loss) than those stocked with HD. Pigs stocked with LD showed lower cortisol level than those stocked with HD. Therefore, Pigs exposed to high stock density (lower than 0.5 m2/100 kg) in high air temperature during pre-slaughter caused acute stress and lead to PSE (pale, soft, exudative) pork incidence. Based on obtained results, stocking of too high (lower than 0.5 m2/100 kg) density is generally not good for meat quality and animal welfare at high temperatures.

Adsorption process efficiency of activated carbon from date pits in removing pollutants from dye wastewater

  • A. Ahsan;I.K. Erabee;F.B. Nazrul;M. Imteaz;M.M. El-Sergany;S. Shams;Md. Shafiquzzaman
    • Membrane and Water Treatment
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    • v.14 no.4
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    • pp.163-173
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    • 2023
  • The presence of high amounts of organic and inorganic contaminants in textile wastewater is a major environmental concern. Therefore, the treatment of textile wastewater is an urgent issue to save the aquatic environment. The disposal of large quantities of untreated textile wastewater into inland water bodies can cause serious water pollution. In this study, synthetic dye wastewater samples were prepared using orange dye in the laboratory. The synthetic samples were then treated by a batch adsorption process using the prepared activated carbon (AC) from date pits. The wastewater parameters studied were the pH, total dissolved solids (TDS), total suspended solids (TSS), electrical conductivity (EC) and salinity. The activated adsorption process showed that the maximum removal efficiencies of electric conductivity (EC), salinity, TDS and TSS were 65%, 92%, 89% and 90%, respectively. The removal efficiencies were proportional to the increase in contact time (30-120 min) and AC adsorbent dose (1, 3 and 5 g/L). The adsorption profile indicates that 5 g/L of adsorbent delivers better results for TDS, EC, TSS and salinity at contact time of 120 min. The adsorption characteristics are better suited to the pseudo-second-order kinetic model than to the pseudo-first-order kinetic model. The Langmuir and Freundlich isotherms were well suited for describing the adsorption or contact behavior of EC and TSS within the studied system.

Effect of Coir Substrate Mixing Ratios on the Growth and Yield of Perilla Leaves under Hydroponics (수경재배 잎들깨의 생육과 수량에 미치는 코이어 배지의 혼합비율 효과)

  • Pyeong-Sic Park;Jong-Won Park;Hye-Kyeong Hyeon;Hyun-Sook Kim;Soo-Sang Hahm;Hak-Hun Kim;Hyo-Gil Choi
    • Journal of Environmental Science International
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    • v.33 no.1
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    • pp.17-25
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    • 2024
  • This study aimed to determine the most suitable coir substrate mixing ratio for optimizing the growth and yield of the "lpduelkkae 1" cultivar. We comprehensively analyzed the physicochemical properties, growth, and yields of four different substrate combinations: perlite (coir with mixing ratios of 70:30 (PC30), 50:50 (PC50), and 30:70 (PC70)) and 100% coir (C100). The results revealed substantial differences in substrate properties. C100 exhibited the highest total porosity and the lowest solid phase, indicating excellent air permeability. The pH levels and electrical conductivity (EC) values ranged from 5.4-6.8 and 1.2-3.1 dS·m-1, respectively. Leaf growth parameters, including length, width, and dry weight, showed positive correlations with high coir ratios, except for PC30. PC70 and C100 outperformed other substrates in stem growth, exhibiting superior stem diameter and fresh and dry weights. The quantity of marketable leaves was the highest in the C100 substrate. Furthermore, C100 comprised integrated levels of essential nutrients, such as Ca and Mg, owing to its high coir content. In conclusion, a coir ratio of approximately 70% (v/v) should be maintained in the substrate for creating an optimal cultivation environment. Furthermore, the selection of humidity-resistant varieties as well as precise nutrient and moisture management for different seasons and growth stages are crucial for a successful perilla leaf hydroponic cultivation.

Early implant placement in sites with ridge preservation or spontaneous healing: histologic, profilometric, and CBCT analyses of an exploratory RCT

  • Stefan P. Bienz;Edwin Ruales-Carrera;Wan-Zhen Lee;Christoph H. F. Hammerle;Ronald E. Jung;Daniel S. Thoma
    • Journal of Periodontal and Implant Science
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    • v.54 no.2
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    • pp.108-121
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    • 2024
  • Purpose: The aim of this study was to compare changes in soft and hard tissue and the histologic composition following early implant placement in sites with alveolar ridge preservation or spontaneous healing (SH), as well as implant performance up to 1 year after crown insertion. Methods: Thirty-five patients with either intact buccal bone plates or dehiscence of up to 50% following single-tooth extraction of incisors, canines, or premolars were included in the study. They were randomly assigned to undergo one of three procedures: deproteinized bovine bone mineral with 10% collagen (DBBM-C) covered by a collagen matrix (DBBM-C/CM), DBBM-C alone, or SH. At 8 weeks, implant placement was carried out, and cone-beam computed tomography scans and impressions were obtained for profilometric analysis. Patients were followed up after the final crown insertion and again at 1 year post-procedure. Results: Within the first 8 weeks following tooth extraction, the median height of the buccal soft tissue contour changed by -2.11 mm for the DBBM-C/CM group, -1.62 mm for the DBBM-C group, and -1.93 mm for the SH group. The corresponding height of the buccal mineralized tissue changed by -0.27 mm for the DBBM-C/CM group, -2.73 mm for the DBBM-C group, and -1.48 mm for the SH group. The median contour changes between crown insertion and 1 year were -0.19 mm in the DBBM-C/CM group, -0.09 mm in the DBBM-C group, and -0.29 mm in the SH group. Conclusions: Major vertical and horizontal ridge contour changes occurred, irrespective of the treatment modality, up to 8 weeks following tooth extraction. The DBBM-C/CM preserved more mineralized tissue throughout this period, despite a substantial reduction in the overall contour. All 3 protocols led to stable tissues for up to 1 year.

Effects of Corticosterone on Beta-Amyloid-Induced Cell Death in SH-SY5Y Cells

  • Bo Kyeong Do;Jung-Hee Jang;Gyu Hwan Park
    • Biomolecules & Therapeutics
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    • v.32 no.1
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    • pp.77-83
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    • 2024
  • Alzheimer's disease (AD) is a neurodegenerative disease characterized by neuronal cell death and memory impairment. Corticosterone (CORT) is a glucocorticoid hormone produced by the hypothalamic-pituitary-adrenal axis in response to a stressful condition. Excessive stress and high CORT levels are known to cause neurotoxicity and aggravate various diseases, whereas mild stress and low CORT levels exert beneficial actions under pathophysiological conditions. However, the effects of mild stress on AD have not been clearly elucidated yet. In this study, the effects of low (3 and 30 nM) CORT concentration on Aβ25-35-induced neurotoxicity in SH-SY5Y cells and underlying molecular mechanisms have been investigated. Cytotoxicity caused by Aβ25-35 was significantly inhibited by the low concentration of CORT treatment in the cells. Furthermore, CORT pretreatment significantly reduced Aβ25-35-mediated pro-apoptotic signals, such as increased Bim/Bcl-2 ratio and caspase-3 cleavage. Moreover, low concentration of CORT treatment inhibited the Aβ25-35-induced cyclooxygenase-2 and pro-inflammatory cytokine expressions, including tumor necrosis factor-α and interleukin-1β. Aβ25-35 resulted in intracellular accumulation of reactive oxygen species and lipid peroxidation, which were effectively reduced by the low CORT concentration. As a molecular mechanism, low CORT concentration activated the nuclear factor-erythroid 2-related factor 2, a redox-sensitive transcription factor mediating cellular defense and upregulating the expression of antioxidant enzymes, such as NAD(P)H:quinone oxidoreductase, glutamylcysteine synthetase, and manganese superoxide dismutase. These findings suggest that low CORT concentration exerts protective actions against Aβ25-35-induced neurotoxicity and might be used to treat and/or prevent AD.