• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.1
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• pp.1-14
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• 2008

Eight comprehensive oceanographic cruises on a squared $30{\times}30\;km$ area have been made to investigate the short and long-term impacts on the water qualities due to the sand mining operations at Exclusive Economic Zone (EEZ) in the central Yellow Sea from 2004 to 2007. The area was categorized to 'Sand Mining Zone', 'Potentially Affected Zone', and 'Reference Zone'. The investigation covered suspended solids, nutrients (nitrate, nitrite, ammonium, phosphate), and chlorophyll-a in seawater and several parameters such as water temperature, salinity, pH, and ORP. Additionally, several intensive water collections were made to trace the suspended solids and other parameters along the turbid water by sand mining activities. The comprehensive investigation showed that suspended solids, nitrate, chlorophyll-a and ORP be sensitively responding parameters of seawater by sand mining operations. The intensive collection of seawater near the sand mining operation revealed that each parameter show different distribution pattern: suspended solids showed an oval-shaped distribution of the north-south direction of 8 km wide and the east-west direction of 5 km wide at the surface and bottom layers. On the other hand, phosphate showed so narrow distribution not to traceable. Also ammonium showed a limited distribution, but its boundary was connected to the high nitrate and chlorophyll-a concentrations with high N/P ratios. From the last 4 years of the comprehensive and intensive investigations, we found that suspended solids, ammonium, nitrate, chlorophyll-a, and ORP revealed the sensitive parameters of water quality for tracing the sand mining operations in seawater. Especially suspended solids and ORP would be useful tracers for monitoring the water qualities of remote area like EEZ in Yellow Sea.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.153-161
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• 2023

The worldwide effects of COVID-19 have led to a surge in online shopping and contactless services. The consumption pattern has caused the issues such as the environmental pollution together with the increase of plastic waste. Reducing the reliance on the petroleum based plastic use for the package and replacing it with environmentally friendly material are the simple ways in order to solve those problems. Paper is an eco-friendly product with high recyclability as the food packaging materials but has still poor barrier properties. A barrier coating on surface of the paper can be achieved with the proper packaging materials featuring water, gas and grease barrier. Polyethylene (PE) or polypropylene (PP) coatings which are generally laminated or coated to paper are widely used in food packaging applications to protect products from moisture and provide water or grease resistance. However, recycling of packaging containing PE or PP matrix is limited and costly because those films are difficult to degrade in the environment. This study investigated the recyclability of modified acrylic emulsion coating papers compared to PE and PP polymer matrixes as well as their mechanical and gas barrier properties. The results showed that PE or modified acrylic emulsion coated papers had better mechanical properties compared to the uncoated paper as a control. PE or PP coating papers showed strong oil resistance property, achieving a kit rating of 12. Those papers also had a significantly higher percentage of screen reject during the recycling process than modified acrylic coated paper which had a screen rejection rate of 6.25%. In addition an uncoated paper had similar value of a screen rejection rate. It may suggest that modified acrylic emulsion coating paper can be more easily recycled than PE or PP coating papers. The overall results of the study found that modified acrylic emulsion coating paper would be a viable alternative to suggest a possible solution to an environmental problem as well as enhancing the weak mechanical and poor gas barrier properties of the paper against moisture.

• Korean Chemical Engineering Research
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• v.62 no.1
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• pp.87-98
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• 2024

This study was conducted to investigate the efficiency of the filtering sets composed of fiberboards, which were fabricated with lignocellulosic fiber and cork oak bark-based activated carbon (COA), as well as traditional Korean paper handmade from mulberry trees (KP) for the filtration of PM, TVOC and HCHO. Three-layers fiberboards (WRF) were fabricated with wood fiber in its surface layers and recycled fiber/COA in its core layer using a protein-based adhesive with the resin content of 8%. Filtering sets were composed of three WRF and one sheet of KP. Concentrations of PM, TVOC and HCHO generated with the combustion of a incense in a sealed laboratory hood were reduced efficiently with the operation of air-purifier installed the filtering sets. Except for the WRF fabricated with 4%/4% resin contents, other WRF were prepared with 5%/3% and 6%/2% resin contents in surface/core layers, and then the WRF were used with KP for the fabrication of filtering sets. Filtration efficiency of the filtering sets was improved as the core-layer resin content applied in the fabrication of WRF decreased. In addition, filtration efficiency of the WRF-based filtering set fabricated with KP of 25 g/m² basis weight was higher than that with KP of 45 g/m² basis weight. Filtering sets composed of three-layers fiberboards (RWF) that recycled fiber and wood fiber/COA were used in its surface and core layers, respectively, and KP-25g showed higher filtration efficiency than those of WRF-based filtering sets. Air-inhalation equipment installed the RWF-based, WRF-based filtering sets and without filtering set were operated in small indoor and large outdoor spaces. Efficiency for filtering PM and TVOC of the RWF-based filtering sets was higher than that of other filtering sets. It is concluded that fiberboard-based filtering sets composed of RWF and KP-25g can be used as a filter for reducing the concentrations of PM and TVOC existed in indoor and outdoor spaces.

• Journal of Life Science
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• v.34 no.7
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• pp.500-508
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• 2024

Recently, there has been increasing interest in enhancing the indoor air quality, particularly in response to the growing utilization of public facilities. The focus of this study was on assessing the efficacy and safety of an air sterilizer equipped with electrolytic salt catalysts. To that end, we evaluated the antimicrobial activity of the vapor spraying from the air sterilizer and its cytotoxicity in condensed form on human cell lines (HaCaT, BEAS-2B, and THP-1). Against the test organisms, which comprised five bacterial strains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium) and one fungal strain (Candida albicans), the air sterilizer exhibited relatively high antimicrobial activities ranging from 10.89 to 73.98% following 1 and 3 hr of vapor spraying, which were notably time-dependent. Importantly, cytotoxicity assessments on human cells indicated no significant harmful effect even at a 1.0% concentration. Comprehensive safety evaluations included morphological observations, gene expression (Bcl-2, Bax) tests, and FACS analysis of intracellular ROS levels. Consistent with previous cytotoxicity findings, these estimates demonstrated no significant changes, highlighting the air sterilizer's safety and antimicrobial activities. In a simulated 20-hr operation within an indoor environment, the air sterilizer not only showed an 89.4% removal of total bacteria but also a 100.0% removal of Escherichia sp. and fungi. This research outlines the potential of the developed electrolytic salt catalyst air sterilizer to effectively remove indoor microbial pollutants without compromising human safety, underscoring the solution that it offers for improving indoor air quality.

• Food Science and Preservation
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• v.31 no.2
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• pp.267-275
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• 2024

Artemisia fukudo Makino belongs to the Asteraceae family, is a halophyte that can grow in salinity soils and is known for its various physiological activities. However, few studies were comparing it according to the growth environment. Therefore, in this study, we analyzed the antioxidant activity, functional ingredients, and safety of Artemisia fukudo Makino according to the growth environment. Total polyphenol content was the highest in native mature leaves, but 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity was higher in cultivated leaves than in native leaves. The total mineral content, excluding sodium, was higher in cultivated than in native leaves. The content of potassium and calcium was higher in cultivated leaves than in native leaves. In addition, heavy metal analysis showed that cultivated leaves were generally lower than those of native leaves. Residual pesticides were not detected in all samples. In conclusion, since there is no significant difference in cultivated leaves compared to native leaves, it was judged that cultivated leaves could be used as a variety to be grown and mass-produced.

• The Journal of Korean Academy of Sensory Integration
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• v.22 no.1
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• pp.1-14
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• 2024

Objective : This study aimed to investigate the impact of Ayres' sensory integration (ASI) intervention on motor skills and occupational participation of preschool children with attention-deficit/hyperactivity disorder (ADHD). Method : Children with ADHD aged between 4 and 6 years who met the inclusion and exclusion criteria were randomly recruited through screening tests. The subjects were divided into an experimental group (10 subjects) and a control group (8 subjects). The instruments used were the Bruininks-Oseretsky test of motor proficiency-2 (BOT-2), Pediatric Evaluation of Disability Inventory (PEDI), and Goal Attainment Scale (GAS) to evaluate occupational participation. The subjects in the experimental group underwent individual sensory integration therapy according to the ASI principles for 40 minutes twice a week in a total of 16 sessions over eight weeks. The control group did not receive the ASI intervention. Data analysis was performed using the Mann-Whitney U test, chi-squared test, Wilcoxon signed-rank test, and Cohen's d test in SPSS 20.0. Results : The ASI experimental group had significantly higher scores in total motor composite, manual coordination, body coordination, strength, and agility in motor function than the control group (p<.05). The two groups did not differ significantly in terms of occupational participation (PEDI), but GAS scores for individual target activities were significantly higher in the experimental group than in the control group (p<.05). Conclusion : This study shows that the ASI intervention has positive effects on motor skills and occupation participation among preschool children with ADHD.

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.3
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• pp.149-158
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• 2024

Purpose: This study aims to investigate the effects of provisional restoration fabrication methods and surface polishing on surface roughness and microbial adhesion through in vitro experiments. Materials and Methods: 120 cylindrical provisional restoration resin blocks (10 × 10 × 2.5 mm) were manufactured according to four fabrication methods, and 30 specimens were assigned to each group. Afterwards, they were divided into non-polishing group, #400 grit SiC polishing group, and #800 grit SiC polishing group and polished to a 10 × 10 × 2 mm specimen size (n = 10). The surface roughness Ra and Ry of the specimen was measured using a Surface Roughness Tester. Three specimens were extracted from each group and were coated with artificial saliva, and then Streptococcus mutans were cultured on the specimens at 37℃ for 4 hours. The cultured specimens were fixed to fixatives and photographed using a scanning electron microscope. For statistical analysis, the two way of ANOVA was performed for surface roughness Ra and Ry, respectively, and the surface roughness was tested post-mortem with a Scheffe test. Results: The fabrication method and the degree of surface polishing of the provisional restorations had a significant effect on both surface roughness Ra and Ry, and had an interaction effect. There was no significant difference in Ra and Ry values in all polishing groups in DLP and LCD groups. Conclusion: The fabrication method and surface polishing of the provisional restoration had a significant effect on surface roughness and showed different adhesion patterns for S. mutans adhesion.

• The Korean Journal of Physiology
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• v.15 no.1
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• pp.27-36
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• 1981

Relatively little has been done on the metabolic changes of the lung produced by the excessive alcohol ingestion to the point of the acute alcohol intoxication. In the present study, an effort was made to clarify the possible changes of the pulmonary surfactant system by the acute alcohol ingestion. The dynamic pulmonary compliance and the levels of protein and inorganic phosphorus (Pi) of both lung lavage and extract were chosen as the parameters of the pulmonary surfactant activities. The albino rats of both sexes were used, and 1.5 ml of 50% ethanol per 100 g body weight was given by oral intubation, and the experiment was performed at 1, 3, 6, 12, and 24 hours after the alcohol ingestion. The rat was sacrificed by cutting the carotid arteries, and blood sample for the determination of hematocrit(Hct) and the blood alcohol concentration was obtained. Both lungs were completely removed without dammage to the lung tissue, and the pulmonary compliance was measured by the changes of pressure-volume(P-V) curves by inflating or deflating the lung with air. Immediately after the P-V curves were recorded, the lung lavage was obtained by washing the lobes with 15ml of isotonic saline 3 times with a syringe. Next, total lungs were homogenized and filtered to obtain the lung extract. The protein and Pi levels were measured using the lung lavage and extract as the samples, and the lung/body weight ratio(L/B ratio) was also calculated. The results thus obtained were compared with the normal values and summarized as follows. The blood alcohol concentration reached the highest level of $0.71{\pm}0.02\;g\;%$ at 1 hr and gradually decreased until 24 hrs$(0.36{\pm}0.02\;g%)$ after the alcohol ingestion, but all the experimental groups showed significant increase comparing with the normal. The highest Hct value was obtained at 1hr$(64.86{\pm}2.45%)$ and significantly elevated value was continued throughout the experiment. The L/B ratio was significantly lowered from 3hrs until 24hrs after the alcohol ingestion but from 6 th hr on, a generally elevated value was observed with a significant value at 12 hrs and gradual recovery to the normal value at 24 hrs after the alcohol ingestion. The pulmonary compliance at inflation and deflation did not change appreciablly from the normal until 3 hrs after the alcohol ingestion but from 6 th hr on, a generally elevated value was observed with a significant value at 12 hrs and gradual recovery to the normal value at 24 hrs after the alcohol ingestion. The protein level of the lung lavage stowed a significantly increased value of $12.36{\pm}0.35\;mg/gm(3rd hr)$, $12.70{\pm}0.74\;mg/gm(12 th hr)$, and $12.65{\pm}0.88\;mg/gm(24 th hr)$, respectively, comparing with the normal value of $10.65{\pm}0.62\;mg/gm$, and the Pi level also showed a similar tendency of significant increase at 12th hr $(7.65{\pm}0.63\;{\mu}mol/gm)$ and 24 th hr$(6.70{\pm}0.36\;{\mu}mol/gm)$ comparing with the normal value of $5.32{\pm}0.20\;{\mu}mol/gm$. The protein level of the lung extract in the alcohol group was generally similar to the normal value with a slight decrease at 1st and 3 rd hr, tut the Pi level of the lung extract was generally increased in the alcohol group, and a significant increase was observed at 6 th hr$(17.77{\pm}1.54\;{\mu}mol/gm)$, 12 th hr$(13.92{\pm}0.78\;{\mu}mol/gm)$ and 24 th hr$(14.57{\pm}0.53\;{\mu}mol/gm)$ of the alcohol ingestion comparing with the normal value of $10.34{\pm}0.37\;{\mu}mol/gm$. From the above, it may be concluded that the acute alcohol intoxication produces the metabolic changes of the lungs by the increased surfactant activities and elevated pulmonary compliance.

• Tuberculosis and Respiratory Diseases
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• v.58 no.5
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• pp.498-506
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• 2005

Background : This study compared the bronchodilator efficacy and safety of tiotropium inhalation capsules ($18{\mu}g$ once daily) with a ipratropium metered dose inhaler (2 puffs of $20{\mu}g$ q.i.d.) in patients with chronic obstructive pulmonary disease (COPD). Method : After the initial screening assessment and a two-week run-in period, patients received either tiotropium $18{\mu}g$ once daily or ipratropium $40{\mu}g$ four times daily over a period of 4 weeks in a double blind, double dummy, parallel group study. The outcome measures were the lung function, the daily records of the peak expiratory flow rate (PEFR), the patients' questionnaire, and the use of concomitant salbutamol. The forced expiratory volume in one second ($FEV_1$) and the forced vital capacity (FVC) were measured 5 minutes before inhalation, and 0.5, 1, 2 and 3 hours after inhaling the study drug on days 0, 14 and 28. Result : In 16 centers, 134 patients with a mean (SD) age of 66 (7) years and a predicted $FEV_1$ of 42 (12)% were analyzed. The trough $FEV_1$ response was significantly higher in the tiotropium group than in the ipratropium group after a four-week treatment period. The weekly mean morning PEFR of the tiotropium group was consistently higher than that of the ipratropium group during the 4-week treatment period with differences ranging from 12.52 to 13.88 l/min, which were statistically significant. Tiotropium was well tolerated by the COPD patients during the 4-week treatment period and had a similar safety profile to ipratropium. Conclusion : This study shows that tiotropium administrated once daily has a superior bronchodilator effect with a similar safety profile in treating COPD patients compared with ipratropium, inhaled four times daily.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.42-49
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• 2012

This study was carried out to investigate the toxicity of food Red No.2 in the Sprague-Dawley (SD) female rat for 4 weeks. SD rats were orally administered for 28 days, with dosage of 500, 1,000, 2,000 mg/kg/day. Animals treated with food Red No.2 did not cause any death and show any clinical signs. They did not show any significant changes of body weight, feed uptake and water consumption. There were not significantly different from the control group in urinalysis, hematological, serum biochemical value and histopathological examination. In conclusion, 4 weeks of the repetitive oral medication of food Red No.2 has resulted no alteration of toxicity according to the test materials in the group of female rats with injection of 2,000 mg/kg. Therefore, food Red No.2 was not indicated to have any toxic effect in the SD rats, when it was orally administered below the dosage 2,000 mg/kg/day for 4 weeks.