• Journal of Environmental Health Sciences
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• v.36 no.5
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• pp.343-350
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• 2010

This study was performed to investigate laboratory workers' exposures to airborne nanoparticles at a university laboratory where acid treatment experiments were conducted on the surfaces of engineered carbon nanotubes (CNTs). The surface area concentrations, number concentrations, and mass concentrations of airborne nanoparticles were measured at personal breathing zones (PBZs) for various tasks using direct reading instruments. For all three metrics, airborne nanoparticle concentrations during the experiments were higher than background levels measured before and after the experiments for all three metrics. Among the various tasks that were performed as part of these experiments, one task that involved filtering a mixture of acid and CNTs showed the highest concentrations in all three metrics, with concentrations of $116.6\;{\mu}m^2$/cc, 24320 pt/cc, and $9.0\;{\mu}g/m^3$, respectively. Nanoparticle surface area concentrations measured at a representative area fluctuated with those at the PBZs in the laboratory. This result indicates that nanoparticles generated during the experiments were not just limited to the PBZs of the workers but were also present throughout the room, potentially exposing co-located workers. CNTs were detected by a transmission electron microscope in an air sample collected while handling the CNTs. All the tasks were performed inside fume hoods, with the sliding sashes open to their required heights. It was noted that the capture velocities of the fume hoods were much lower than the American National Standards Institute (ANSI)'s recommendation level (0.4 to 0.6 m/s). In conclusion, this study showed that, due to inadequate control, laboratory researchers performing acid treatment experiments on surfaces of CNTs were exposed to airborne nanoparticles generated during the tasks.

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.113-124
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• 2016

Red ginseng is known to have many beneficial effects. Cisplatin, an effective antineoplastic drug, can cause many side effects like irreversible sensorineural hearing loss and serious tinnitus in humans. This study is aimed to reduce a cisplatin's side effect, nephrotoxicity by fermentated korean red ginseng. Korea ginseng was produced by steaming and dring and fermentation. And mice were divided into 4 groups- (A) normal mice, (B) Vehicle treated cisplatin mice, (C) RG0F0-treated cisplatin mice, (D) RG8F3-treated cisplatin mice. C and D groups were feed each material 200 mg/kg/day during 4 days. And cisplatin 20 mg/kg injected to B, C, and D groups as abdominal injection. After 24 h, blood sample was collected. The kidneys were harvested for histological, immuno histochemical and western blot analysis. 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity was depended on steaming hours. RG0F0 and RG8F3 (ginseng-8 h steamed and fermented by Saccharomyces cerevisiae) were showed antioxidants effect in DPPH and ABTS radical scavenging activity. Component amounts according to steaming hours. 8 h steamed red ginseng had the most ingredients of ginsenoside. Treatments with RG8F3 reduced cisplatin-induced nephrotoxicity in the mice resulting in increase of GSH and decrease of ROS, BUN, creatinine, and inflammatory mediators. This result seems to be involved with the restriction of the inflammation in the kidney. Therefore, fermented red ginseng might have therapeutic efficacy in reduce kidney injury induced by cisplatin treatment.

• The Journal of Pediatrics of Korean Medicine
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• v.21 no.3
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• pp.125-143
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• 2007

Objective The purpose of this study was to investigate health and life style of pediatric outpatients who visited the oriental hospital. Methods The study was composed of 363 students from elementary school, middle school and high school who visited the pediatrics department in $\bigcirc\;\bigcirc$ university oriental medicine hospital between 2005 and 2006. Results 1. The group wasconsisted with 56% of male and 44% of female student and for the age distribution, 7.4% were elementary school students, 55.6% were middle school students, and 36.9% were high school students. 2. Usually the eldest child tends to visit hosipital more than the younger ones. 3. More than a half of those students' parent had University education or beyond that. 4. There were more students who had below the level of the height-weight curve than in the higher level. 5. The average study hours of the students were 3.67 hours. An average sleep hours was 6.18 hours. An average exercise hour was 1.16 hours and an average time for watching TV was 1.71 hours. 6. Many students had hard time to concentrate on the studying for a long time. 7. For the question about the reason why they got the poor grade, they answered because of the lower concentration, and they didn't put much effort on the studying. The most they concern about was their grade. 8. Most of the students who visited the clinic said they did not feel refreshed when they woke up in the morning, and, many of them said that they don't feel okay. 9. More than an half of the students wear glasses. 10. More than an half of the students answered that they often catch a cold when the weather changes a lot. 11. A lot of them had some digestive problems. 12. As they getting older, they said they often feel back pain and shoulder pain. 13. Many students felt irritated and got mad easily. Many of them felt bored about their study and stressed out because of their tests and the university entrance exams. 14. Most of the female students answered that they have irregular period or cramps. 15. 21% of them usually skip breakfast. 16. Many students enjoyed snacks. Most of them enjoyed snacks after school. As they go into higher grade, they would like to eat at night especially cookies, bread and fruits. Conclusions Further studies with larger sample size of students will be neededfor accurate results, and it would be better if we can compare the conditions of the students before treatments and after those.

• Journal of Animal Environmental Science
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• v.15 no.2
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• pp.91-98
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• 2009

Object of this study were to determine the influence of collection times of rumen fluid on in vitro dry matter digestibility (IVDMD) of forage crops. The donor cow was fed concentrate once a day and given free access to grass-legume mixture hay. Main plot was consisted of different collection time of rumen fluid; T1: 1 hour before concentrate feeding, T2: 1 hour after feeding, T3: 4 hour after feeding and T4: 8 hour after feeding. A total of 7 samples of 4 different forage crops (barely, Italian ryegrass, crimson clover, rye) were used for the estimation of IVDMD and tested in three replicates. For the $DAISY^{II}$ incubation, each sample was inserted into each filter bag then heat-sealed and incubated in a digestion vessel for 48 h at $39^{\circ}C$. The times of rumen fluid collection had no significant effect on the IVDMD values over all varieties except for 2 breeds of IRG (Kogreen and Kospeed). IVDMD values with T1 over all varieties were slightly higher than other treatments, however those with both T1 of Kogreen and Kospeed varieties were significantly higher than T2 (p<.05).

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.991-996
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• 2000

Enzyme-linked immunosorbent assay was developed for the analysis of soy protein in foods. Competitive indirect ELISA (ciELISA) was established by using specific antibodies against the heat-stable acidic subunits (AS) of glycinin. Soy proteins in each sample used in this study were solublized in the presence of urea and DTT and boiled at $100^{\circ}C$ for 1hr and then were renatured with a cystine-containing solution. After these treatments, each isolated soy protein (ISP) heated at 60, 70, 80, $90^{\circ}C$ for 10 minutes showed almost the same curve as unheated one in the ciELISA. The detection limit of ISP was 0.3 ${\mu}g/mL$. Anti-AS antibodies have very low reactivities less than 0.1% toward non-meat proteins such as skim milk and casein and did not show any reactivities toward egg white powder and ovalbumin. When laboratory-made sausages containing ISP of $0.5{\sim}3%$ were assayed by ciELISA, the mean recovery was about 83% (C.V., 19%). In addition, the average content of soy protein in commercial sausages was 1.27%.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1073-1080
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• 2018

There are several types of petroleum products used for the fuel oil, according to their respective quality standards, grades and usage. Depending on the degree of oil tax rate by country, even the same petroleum products will have price gap. The illegal mixing of cheap petroleum products, which are subject to the lower tax rate, with relatively expensive transportation fuel causes problems such as tax evasion, environmental pollution and vehicle breakdown. In order to prevent illicit production and mixing of these different petroleum products, a small amount of markers are legally added to specific petroleum products. In Korea, markers are introduced and used to prevent illegal activity that kerosene used as fuel for house and commercial boiler are mixed with automotive diesel fuels, and marker contents are analyzed to use UV-Vis spectrophotometer and high performance liquid chromatography (HPLC). In this study, we have developed a method to qualitatively and quantitatively determine the marker added to petroleum products by gas chromatography-mass spectrometry (GC-MS) without adding developing reagent or sample pre-treatments.

• Journal of Korean Academy of Oral Health
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• v.42 no.4
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• pp.136-144
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• 2018

Objectives: The aim of this study is to analyze the differences in factors related to the incidence of dental caries between children in fluoridated and non-fluoridated areas and compared the DMFT and DMFS scores to confirm the effect of water fluoridation program (WFP) in Geoje and Changwon. Methods: The oral health examination and questionnaire survey were conducted in fluoridated and non-fluoridated areas. The number of surveyed children aged 8, 10, and 12 years in the fluoridated and non-fluoridated area of two cities was 1,524 and 1,383, respectively. Self-recorded questionnaires included self-perception of their own dental health, daily toothbrushing frequency, intake frequency of cariogenic sweet snacks and beverages, experience of gingival bleeding, experience of unmet dental treatment, and use of oral hygiene device except for toothbrush and toothpaste. The prevalence of caries and fissure-sealant status were surveyed. The logistic regression analysis was used to analyze the difference in children's self-rated oral health status between the fluoridated and non-fluoridated area. The mean number of sealed teeth and surfaces, marginal means of the DMFT and DMFS scores adjusted for the difference in the samples' sex distribution, and region were compared between the fluoridated and non-fluoridated areas. Results: In the fluoridated area, the experience rate of unmet dental treatments was higher among children aged 10 years, intake frequency of cariogenic sweet snacks and beverages were higher among the whole sample, and experience rate of professional fluoride application were lower than in the non-fluoridated area. The DMFT score for permanent dentition adjusted for differences in sex, region, and mean number of fissure-sealed teeth in the fluoridated area was significantly lower among whole samples and 8-, 10-, and 12-year-olds alone than in the non-fluoridated area. Conclusions: WFP can alleviate oral health inequality because it is effective in reducing the incidence of caries among children is disadvantaged demographic, socioeconomic, and cultural contexts.

• The Korean Journal of Applied Statistics
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• v.34 no.3
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• pp.309-327
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• 2021

Dynamic treatment regimes (DTRs) are decision-making rules designed to provide personalized treatment to individuals in multi-stage randomized trials. Unlike classical methods, in which all individuals are prescribed the same type of treatment, DTRs prescribe patient-tailored treatments which take into account individual characteristics that may change over time. The Q-learning method, one of regression-based algorithms to figure out optimal treatment rules, becomes more popular as it can be easily implemented. However, the performance of the Q-learning algorithm heavily relies on the correct specification of the Q-function for response, especially in observational studies. In this article, we examine a number of double-robust weighted least-squares estimating methods for Q-learning in high-dimensional settings, where treatment models for propensity score and penalization for sparse estimation are also investigated. We further consider flexible ensemble machine learning methods for the treatment model to achieve double-robustness, so that optimal decision rule can be correctly estimated as long as at least one of the outcome model or treatment model is correct. Extensive simulation studies show that the proposed methods work well with practical sample sizes. The practical utility of the proposed methods is proven with real data example.

• Food Science of Animal Resources
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• v.42 no.1
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• pp.153-174
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• 2022

This trial was conducted to evaluate the effect of overwrap, vacuum, and modified atmosphere packaging (MAP) on poultry breast fillets' microbiological, biochemical shelf life and sensory attributes. The fillets were divided into 4 groups, and each of the treatments was replicated 3 times with 60 breast fillets. The first group was a control group with overwrap packaging; the second group was vacuum packed (VP); the third and fourth groups were MAP-1: 0% O₂, 40% CO₂, 60% N₂, and MAP-2: 20% O₂, 40% CO₂, 40% N₂. The microbiological and biochemical analyses were performed for the total viable count, coliform count, Pseudomonas count, Salmonella count, total volatile basic nitrogen (TVB-N), pH, cooking loss, color, lipid oxidation, tenderness, and sensory analysis. The data were analysed through two-way ANOVA by Minitab (Minitab 17.3.1). Meat treated with understudy MAP compositions and vacuum packaging reduced total viable count, Pseudomonas count, and total coliform count than control (p<0.05). TVB-N remained below the recommended limit throughout storage except aerobic packaging (p<0.05). Cooking loss (%) was lowered and showed non-significant results (p>0.05) between vacuum packaging and both MAP concentrations. The meat stored in MAP-2 was characterised by higher (p<0.05) visual scores. Whilst MAP-1 showed higher (p<0.05) L^* values and overall acceptability. Sample packaged under aerobic packaging showed significant (p<0.05) results for b^* and thiobarbituric acid reactive substances (TBARS). Meat stored in aerobic packaging showed higher (p<0.05) shear force values. The outcome of this trial may help to promote the application of understudy MAP compositions and rapid detection of microbes by biochemical analysis under local conditions.

• Journal of Animal Science and Technology
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• v.64 no.2
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• pp.380-395
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• 2022

This study investigated the utilization of detoxified Rhus verniciflua (RV) extract as a natural antioxidant to extend the shelf life of chicken breast meat during storage. Pre-heating at (35℃, 100℃, 120℃, and 140℃) was conducted on heartwood of RV prior to extraction to improve its antioxidant activity and remove the allergenic compound urushiol. The antioxidant activity was the highest when RV pre-heated at 120℃ with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) scavenging activity observed at 62.29 EC₅₀ ㎍/mL and 12.11 IC₅₀ mg/mL, respectively. Pre-heating also significantly increased the total phenolic content (TPC), with the highest improvement was seen at 120℃, 100℃, and 140℃ respectively, wherein 35℃ shared no difference with the raw RV (RRV). Urushiol content was vanished following pre-heating at 120℃ and 140℃. With respect to these result, pre-heating treatment at 120℃ was applied before the extraction of the heartwood of RV. Prepared breast meat sample was dipped into distilled water as a negative control, 0.02% butylated hydroxytoluene (BHT) as positive control, and a solution containing detoxified RV extract (0.10%, 0.25%, 0.50%, 1.00%) at 4℃ for 60 min. Treatment group with 0.50% and 1.00% addition increased the redness and yellowness value on day 6 and day 3 of storage respectively (p < 0.05). The pH value of breast meat was also increased in treatment of 0.50% and 1.00% on day 0, but subsequently lower until end of storge day compared to control negative (p < 0.05). Furthermore, 0.50% treatment exhibited a higher antioxidant activity, stronger inhibition of the microbial growth evaluated by total viable count and maintaining a lower total volatile basic nitrogen among treatments (p < 0.05), unless for BHT and 1.00% treatment groups (p > 0.05). It indicates a similar efficacy of detoxified RV extract with that of positive control treated with BHT. The results of this study suggested that dipping chicken breast meat into a solution containing 0.50% of previously pre-heated RV heartwood at 120℃ could be a promising natural antioxidant for extending the shelf life, and at the same time improve its quality during storage.