• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.325-333
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• 2020

Current methods of measuring the sediment concentration of natural streams can be affected by weather conditions and have lower reliability in bed-load sections due to mechanical limits. Theoretical methods have to be used to solve this problem, but they have low reliability compared to the measured values and diverse results for the bed-load sediment concentration. This study proposes a new way to reliably determine the bed-load sediment concentration from the relation with theoretical depth-integrated concentration based on the informational entropy concept. Sediment distribution shows a uniform probability distribution under maximized entropy conditions under some constraints, so a function can be calculated for the sediment distribution and depth-integrated concentration. The parameters of a stream were estimated by a nonlinear regression method using the concentration data from a past experiment. Equilibrium N (EN) was estimated using the relation between two different formulas proposed in this study, which can ease the estimation of both the total sediment distribution and depth-integrated sediment concentration with high reliable results with an average R2 of 0.924.

• Journal of Nutrition and Health
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• v.47 no.1
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• pp.23-32
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• 2014

Purpose: This study was conducted in order to investigate the effect of Sargassum confusum extracts on the reduction of body fat for eight weeks in overweight women ($BMI{\geq_-}23kg/m^2$). Methods: Subjects were classified by double-blind randomized trial as the control group (C group, n = 14) and the Sargassum confusum extract supplementation group (SC group, n = 16), which consumed 12 tablets per day. Questionnaires related to their health status were assessed twice (week 0 and week 8). Their dietary intake status was evaluated by 24-recall method and body compositions were measured using a bioelectrical impedance analyzer. In addition, we assessed the anti-obesity effect and the occurrence possibility of health risk factors during the supplementation periods by hematological and clinical analysis of blood. Results: Waist circumference and body fat (%) were significantly decreased in the SC group. Serum leptin level was also significantly decreased in the SC group. Defecation frequency was significantly increased in the SC group. The above results indicate that Sargassum confusum extract supplementation improves overweight on visceral fat and blood leptin level by increasing bowel movement. These results imply a decrease of health risk factors in overweight women. Seven subjects withdrew from the study due to adverse events; however, no differences regarding adverse events were observed between the control and treatment group. Conclusion: Therefore, Sargassum confusum extract is a plausible effective agent for body fat reduction in humans.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.1-5
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• 2016

BACKGROUND: Burcucumber(Sicyos angulatus L.) is an invasive plant species and disturbs ecosystems in Korea. The main method for prevention of burcucumber is cutting or pulling out. However, the studies accounting for the use of the by-product of burcucumber after cutting remain incomplete. Thus, the aim of this study was to investigate the applicability of burcucumber as a substitute for nitrogen fertilizer.METHODS AND RESULTS: Burcucmber plants only including stem, leaves, and petiole were collected from the Sky Park in Seoul and divided in to three categories based on the length of stem of burcucumber; 10-30 cm, 30-100 cm, and 100-200 cm. And they were input into soil with 20 kg-N/10 a. After 4 weeks aging, chemical properties of treated soils and the productivity of lettuce(Lactuca sativa L.) were examined. Both the inorganic nitrogen contents in soils and the growth of lettuce were increased with the decreases in length of burcucumber standing for young plant. And the inorganic nitrogen content and the productivity of lettuce were positively correlated(r= 0.9409).CONCLUSION: The C/N ratio of burcucumber was low, indicating fast decomposition and nitrogen supplying rate, resulting in the increase in lettuce growth. Burcucumber could be a good substitute for nitrogen organic fertilizer.

• Food Science and Preservation
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• v.24 no.7
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• pp.949-956
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• 2017

This study attempted to find optimum extract range of active ingredient for barley sprouts (Hordeum vulgare L.). Extracts from Hordeum vulgare L. were made by microwave extraction method and total polyphenol content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity (DPPH) were measured with extract of Hordeum vulgare L.. Response surface methodology (RSM) was applied to a extraction process, and central composite design (CCD) was also used for this process to examine the optimum condition. Independent variables ($X_n$) are concentration of ethanol ($X_1$: 0, 25, 50, 75, 100%), microwave power ($X_2$: 60, 120, 180, 240, 300 W), extraction time ($X_3$: 4, 8, 12, 16, 20 min). Dependent variables ($Y_n$) are TPC ($Y_1$), TFC ($Y_2$), DPPH radical scavenging ($Y_3$). It is formed by sixteen conditions to extract. The $R^2$ value of dependent variables is ranged from 0.90 to 0.97 (p<0.05). Experiments values within the optimal range (40% of ethanol concentration, 120 W of microwave power, 18 min of extraction time) were 3.74 mg GAE/g (TPC), 3.00 mg RE/g (TFC), 35.43% (DPPH), respectively. Under the optimized conditions, predicted value showed no significant difference comparing with the experimental values.

• Clean Technology
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• v.26 no.2
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• pp.122-130
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• 2020

The isotherm, kinetic, and thermodynamic parameters of reactive blue 4 adsorbed by activated carbon were investigated for activated carbon dose, pH, initial concentration, contact time, and temperature data. The adsorption of the RB 4 dye by activated carbon showed a concave shape in which the percentage of adsorption increased in both directions starting from pH 7. The isothermal adsorption data were applied to Langmuir, Freundlich, and Temkin isotherms. Both Freundlich and Langmuir isothermal adsorption models fit well. From determined Freundlich separation factor (1/n = 0.125 ~ 0.232) and Langmuir separation factor (R_L = 1.53 ~ 1.59), adsorption of RB 4 by activated carbon could be employed as an effective treatment method. The constant related to the adsorption heat (B_T = 2.147 ~ 2.562 J mol^-1) of Temkin showed that this process was physical adsorption. From kinetic experiments, the adsorption process followed the pseudo second order model with good agreement. The results of the intraparticle diffusion model showed that the inclination of the first straight line representing the surface diffusion was smaller than that of the second straight line representing the intraparticle pore diffusion. Therefore, it was confirmed that intraparticle pore diffusion is the rate-controlling step. The negative Gibbs free energy change (ΔG = -3.262 ~ -7.581 kJ mol^-1) and the positive enthalpy change (ΔH = 61.08 kJ mol^-1) indicated the spontaneous and endothermic nature of the adsorption process, proving this process to be spontaneous and endothermic.

• Proceedings of the Korea Crystallographic Association Conference
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• 2003.05a
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• pp.18-18
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• 2003

Thioredoxin (Trx) is a small redox protein that is ubiquitously distributed from achaes to human. In diverse organisms, the protein is involved in various physiological roles by acting as electron donor and regulators of transcription and apoptosis as well as antioxidants. Sequences of Trx within various species are 27～69% identical to that of E. coli and all Trx proteins have the same overall fold, which consists of central five β strands surrounded by four α helices. The N-terminal cysteine in WCGPC motif of Trx is redox sensitive and the motif is highly conserved. Compared with general cysteine, the N-terminal cysteine has low pKa value. The result leads to increased reduction activity of protein. Recently, novel thio.edoxin-related protein (TRP14) was found from rat brain. TRP14 acts as disulfide reductase like Trx1, and its redox potential and pKa are similar to those of Trx1. However, TRP14 takes up electrons from cytosolic thioredoxin reductase (TrxR1), not from the mitochondrial thioredoxin reductase (TrxR2). Biological roles of TES14 were reported to be involved in regulating TNF-α induced signaling pathways in different manner with Trx1. In depletion experiments, depletion of TRP14 increased TNF-α induced phosphorylation and degradation of IκBα more than the depletion Trx1 did. It also facilitated activation of JNK and p38 MAP kinase induced by TNF-α. Unlike Trx1, TRP14 shows neither interaction nor interference with ASK1. Here, we determined three-dimensional crystal structure of TRP14 by MAD method at 1.8Å. The structure reveals that the conserved cis-Pro (Pro90) and active site-W-C-X-X-C motif, which may be involved in substrate recognition similar to Trx1 , are located at the beginning position of strand β4 and helix α2, respectively. The TRP14 structure also shows that surface of TRP14 in the vicinity of the active site, which is surrounded by an extended flexible loop and an additional short a helix, is different from that of Trx1. In addition, the structure exhibits that TRP14 interact with a distinct target proteins compared with Trx1 and the binding may depend mainly on hydrophobic and charge interactions. Consequently, the structure supports biological data that the TRP14 is involved in regulating TNF-α induced signaling pathways in different manner with Trx1.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.112-118
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• 2018

Adsorption equilibrium, kinetic and thermodynamic parameters of a brilliant green from aqueous solutions at various initial dye concentration (10~30 mg/L), contact time (1~24 h) and temperature (298~318 K) on zeolite were studied in a batch mode operation. The equilibrium adsorption values were analyzed by Langmuir, Freundlich and Dubinin-Radushkevich model. The results indicate that Langmuir and Freundlich model provides the best correlation of the experimental data. Base on the estimated values of Langmuir dimensionless separation factor ($R_L=0.041{\sim}0.057$) and Freundlich constant (1/n=0.30~0.47), this process could be employed as effective treatment method. calculated values of adsorption energy by Dubinin-Radushkevich model were 1.564~1.857 kJ/mol corresponding to physical adsorption. The adsorption kinetics of brilliant green were best described by the pseudo second-order rate model and followed by intraparticle diffusion model. Thermodynamic parameters such as activation energy, free energy, enthalpy and entropy were calculated to estimate nature of adsorption. negative Gibbs free energy (-10.3~-11.4 kJ/mol), positive enthalpy change (49.48 kJ/mol) and Arrehenius activation energy (27.05 kJ/mol) indicates that the adsorption is spontaneous, endothermic and physical adsorption process, respectively.

• Journal of Environmental Impact Assessment
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• v.28 no.6
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• pp.592-603
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• 2019

This study is about the implementation of low energy sewage management technology through effective control of blower which consumes the most energy in sewage treatment. In calculating the amount of oxygen required for microorganisms, unlike the existing method using the operating index in the bioreactor or TMS data in the discharge port, the CODcr and NH₄⁺-N concentration changes in sewage flowing into the sewage treatment plant were detected in advance before entering the bioreactor and the amount of air was controlled based on this. The pre-sensing was found to have a high correlation compared with conventional products. As a result of blower control, it was possible to save about 9.9% energy more than the manual control. Consequently, this study suggested the possibility of blower's real-time control combined with pre-sensing technology. Also, it is expected that the low energy sewage treatment can be applied to sewage treatment facilities dependent on operation by manpower, and it will contribute to the reduction of greenhouse gas emissions.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.238-247
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• 2021

This study is a descriptive research to investigate the, safety environment, and performance of nurses working in public medical institutions on standard precautions for infection, and to identify factors affecting the performance of standard precautions for infection. As for the research method, data were collected through a questionnaire on 192 nurses from two public medical institutions in S city and N city, and the results were analyzed using the SPSS WIN 22.0 statistical program. From the research results, there was a significant difference in the knowledge of standard precautions according to work experience, and there was a significant difference in the safety environment of standard precautions according to the position. The average level of knowledge of standard precautions was 21.98/25 points, the average safety environment was 5.68/7 points, and the average performance was 40.28/60 points. There was a significant positive correlation between the safety environment of standard precautions and the performance of standard precautions (r=.21, p<0.01). The affecting factor on the performance of standard precautions was found to be the safety environment of standard precautions(𝛽=.22, p=.003). Therefore, to improve the performance of standard precautions for nurses' infection control in public medical institutions, Different and persistent infection management educational programs that consider the Historical situation and monitoring are required other than providing financial support and supportive safety environment.

• Journal of Microbiology and Biotechnology
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• v.34 no.5
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• pp.1146-1153
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• 2024

The increasing economic losses associated with growth retardation caused by Enterocytozoon hepatopenaei (EHP), a microsporidian parasite infecting penaeid shrimp, require effective monitoring. The internal transcribed spacer (ITS)-1 region, the non-coding region of ribosomal clusters between 18S and 5.8S rRNA genes, is widely used in phylogenetic studies due to its high variability. In this study, the ITS-1 region sequence (~600-bp) of EHP was first identified, and primers for a polymerase chain reaction (PCR) assay targeting that sequence were designed. A newly developed nested-PCR method successfully detected the EHP in various shrimp (Penaeus vannamei and P. monodon) and related samples, including water and feces collected from Indonesia, Thailand, South Korea, India, and Malaysia. The primers did not cross-react with other hosts and pathogens, and this PCR assay is more sensitive than existing PCR detection methods targeting the small subunit ribosomal RNA (SSU rRNA) and spore wall protein (SWP) genes. Phylogenetic analysis based on the ITS-1 sequences indicated that the Indonesian strain was distinct (86.2% nucleotide sequence identity) from other strains collected from Thailand and South Korea, and also showed the internal diversity among Thailand (N = 7, divided into four branches) and South Korean (N = 5, divided into two branches) samples. The results revealed the ability of the ITS-1 region to determine the genetic diversity of EHP from different geographical origins.