• Journal of Radiation Industry
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• v.5 no.2
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• pp.159-164
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• 2011

A variety of natural polymers have been used as tissue engineering scaffolds, drug delivery system, and cosmetic materials due to their higher biocompatibility and water uptake. As a major component of extracellular matrix, hyaluronic acid consisting of D-glucuronic acid and N-acetylglucosamine has been popularly used as a hydrogel material. Even though it has good properties to be used in the tissue engineering and cosmetic industry, its higher viscosity has limited a potential use in a variety of applications; only low content should be applied in preparing above products. In the present study, we investigated the effect of electron beam irradiation on the properties of hyaluronic acid. Hyaluronic acid paste containing low contents of water changed to solution after electron beam irradiation ranging from 1 to 10 kGy, which didn't exhibit any alteration of surface properties and morphological change after freeze-drying. However, its viscosity was significantly decreased as absorbed dose increased, which was approximately one by hundred in comparison with the viscosity of original hyaluronic acid solution with same concentration. In addition, it can still interact with positive charged chitosan generating polyelectrolyte complex. Therefore, only viscosity was decreased after electron beam irradiation, whereas other properties of hyaluronic acid maintained. Consequently, these hyaluronic acids with lower viscosities can be used in a variety of applications in tissue engineering, drug delivery, and cosmetic industry.

• The Journal of Korean Society for School & Community Health Education
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• v.4
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• pp.43-59
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• 2003

The purpose of this study was to examine whether the gender, grade and school type of middle school students made any differences to their sexual awareness and sexual behaviors in an effort to lay the groundwork for providing more efficient sex education. The research questions were posed as follows: First, what is the sexual awareness of middle school students? Second, what are the sexual behaviors of middle school students? Third, are their gender, school year and school type related to their sexual awareness and behaviors? The subjects in this study were 976 middle school students from Gyeonggi province. After a survey was conducted with questionnaires prepared by this researcher based on earlier studies to suit the purpose of the study, the collected data were analyzed with SPSS 10.0 program. The frequency analysis, x2 test and correlational analysis were implemented, and basic statistical data were obtained. The conclusions were as follows: First, regarding their sexual awareness, the largest group of them agreed that one must report in case of being raped(4.36), and the smallest number of them thought that one might have a sexual relationship with a person other than his or her spouse after marriage(1.56). Second, as for experience of indecent materials, part of sexual behaviors, 67.4 percent had ever contacted such materials. The most common medium through which they contacted them was the Internet(56.5%). The above-mentioned findings suggested that the sexual awareness of the middle school students wasn't influenced by gender or school type. But that varied with grade, as the third graders had the best sexual consciousness. Their sexual behaviors were different according to gender. The boy students contacted more indecent materials, and their experience of such materials varied with grade, since the third graders contacted the most obscene materials. And that also varied with school type, and the non-engineering students contacted more obscene materials. As for sexual drives, their masturbation experience was different according to gender, grade and school type. The number of the boys who practiced masturbation was four-fold larger than that of the girls, and the second graders had more such experience. By school type, the non-engineering students practiced more masturbation, but there was no significant gap between their kissing, caressing and dating experiences.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.421-427
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• 2015

Angelica gigas Nakai is one of the most widely used herbal medicines and is known to have many pharmaceutical effects including an anti-oxidant, anti-cancer etc. This study was carried out to investigate an effect of fertilization on leaf yield, production of dry-matter and accumulation of pyranocurmarine compounds such as decursin (DE) and decursinol angelate (DA) in Angelica gigas Nakai. Effect of fertilization was determined from response surface regression equation composing of 2 by 3 factorial arrangement of urea, sodium dihydrogen phosphate and potassium chloride. Yield of leaf in Angelica gigas Nakai significantly increased until 100 days after transplanting. Production of leaf also tended to increase with increasing nitrogen fertilization. Model of regression equation showed that leaf production depended upon nitrogen ($Pr>{\mid}t{\mid}$ : 0.087, 0.256 and 0.079). Also, statistical results between nitrogen application level and production of dry-matter showed significant relationship (p<0.05) and contents of dry-matter was highest in 10 kg 10a-1 treatment on 24 Sep. Active compound isolated and purified from leaf and root of Angelica gigas Nakai was identified as DE and DA by gas chromatograph-mass spectrophotometry (GC-MS). Concentration of DA as prevalent compound in leaf was highest on 20 Aug. but decreased on 24 Sep. Amount of DE and DA accumulated in Angelica gigas Nakai significantly increased with growth stages and nitrogen level. The result of our investigation imply that nitrogen fertilization is important factor for production of leaf and accumulation of pyranocurmarine in Angelica gigas Nakai as a medicinal/food materials.

• Nutrition Research and Practice
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• v.13 no.5
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• pp.393-398
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• 2019

BACKGROUND/OBJECTIVES: The association between tea consumption and risk of coronary heart disease (CHD) remains controversial. This study aimed to determine whether tea consumption has an effect on CHD risk in Chinese adults. SUBJECTS/METHODS: In this hospital-based case-control study, 267 cases of CHD and 235 non-CHD controls were enrolled. Blood samples from all cases were examined. Cardiac function indices (left ventricular ejection fraction, left ventricular end-diastolic dimension, lactate dehydrogenase, and creatine kinase of the muscle or brain type), blood lipid index (high-density lipoprotein cholesterol), and blood coagulation function indices (fibrinogen and activated partial thromboplastin time) were recorded. Tea consumption of study participants was assessed by a specifically designed questionnaire. The baseline characteristics of the study populations were recorded, and CHD-related biomarkers were detected. Differences in baseline characteristics of the study participants were examined using t-tests for continuous variables and chi-squared tests for categorical variables. Unconditional logistic regression was used to measure the association between tea and CHD. RESULTS: There were significant differences in cardiac function indices, blood lipid index, and blood coagulation indices between CHD cases and controls (P < 0.05). We found tea consumption reduced CHD risk in female participants (adjusted odds ratio (OR) = 0.484, 95% CI: 0.242-0.968, P = 0.0403). Regarding the type of tea consumed, the risk of CHD was reduced in women who drank partially fermented tea (adjusted OR = 0.210, 95% CI: 0.084-0.522, P = 0.0008). Analytic results for the amount of tea consumed per unit time showed CHD risk was reduced in women who consumed 1-2 cups of tea per day (adjusted OR = 0.291, 95% CI: 0.131-0.643, P = 0.0023). A tea-drinking frequency of > 6 days/week was beneficial for CHD prevention (adjusted OR = 0.183, 95% CI: 0.049-0.679, P = 0.0112). When analyzed according to the duration of tea consumption, the risk of CHD was reduced in participants who had been drinking tea for 10-20 years (adjusted OR = 0.360, 95% CI: 0.137-0.946, P = 0.0382). CONCLUSIONS: Tea consumption is associated with a reduced risk of CHD in female but not male populations in Guangzhou.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.18 no.2
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• pp.55-61
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• 2018

Orinithine transcarbamylase (OTC) deficiency is the most common inborn error of the urea cycle with resulting hyperammonemia, which is medical emergency in newborns.We recently had a case of a boy that presented with lethargy, seizure, hyperammonemia and hypocalcemia in neonatal period. He was diagnosed with OTC deficiency by two consequent ways which are initial biochemical phenotype including hyperammonemia and an increased orotic acid in his urine and genetic analysis of the OTC gene. The OTC gene showed a novel hemizygous mutation c.913C>T (p.Pro305Ser). He was treated by low protein intake, sodium benzoate, phenylbutyrate sodium, L-arginine, and continuous renal replacement therapy (CRRT). After discharge, he has a relatively good prognosis without notable developmental delay. For good prognosis, the duration of hyperammonemia should be shorten. And it can be reached by an early diagnosis. For early detection of OTC deficiency, targeted exome sequencing will be a important role as well as biochemical tests.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.30 no.1
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• pp.2-8
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• 2019

Objectives: This study aimed to compare the quality of life reported by patients with attention-deficit/hyperactivity disorder (ADHD) to the patients' quality of life as reported by their caregivers. In addition, it aimed to examine how emotional problems, including depression and anxiety, and the severity of the symptoms affect the quality of life reported by the patients and their caregivers. Methods: The patients' quality of life and their degree of depression and anxiety were measured using the Pediatric Quality of Life Inventory (PedsQL) 4.0 Child Self-Report, the Children's Depression Inventory (CDI), and the Revised Children's Manifest Anxiety Scale, respectively. The caregivers' perception of the patients' quality of life and severity of the ADHD symptoms were measured using the PedsQL 4.0 Parent Proxy Report and the Conners' Parent Rating Scale (CPRS), respectively. A total of 66 participants completed the survey. The independent-samples t-test, Pearson's correlation analysis, and multiple regression analysis were conducted. Results: The mean score of the PedsQL 4.0 Child Self-Report was significantly higher than the mean score of the PedsQL 4.0 Parent Proxy Report. However, for school function, the PedsQL 4.0 Child Self-Report score was significantly lower than that of Parent Proxy Report. The correlation between the PedsQL 4.0 Child Self-Report and PedsQL 4.0 Parent Proxy Report scores was significant only for emotional function and social function. The multiple regression analysis showed that the PedsQL 4.0 Child Self-Report and PedsQL 4.0 Parent Proxy Report scores were significantly predicted by the CDI and CPRS scores, respectively. Conclusion: Our results demonstrate that there are clear differences between the quality of life reported by the patient themselves and that reported by their caregivers. In addition, the findings suggest that it is critical to treat the patients' accompanying depressive symptoms.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.587-593
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• 2018

This study was carried out to investigate the effect of roasted rice bran (RRB) on the rheological properties of bread dough. According to farinograph analysis, the consistency of the control sample was greatest. There were no significant differences in water absorption (p<0.05). Lower values of development time, stability, and time to breakdown, which were affected, by the addition of RRB, were observed for RRB-containing dough samples, compared to the control dough sample. Addition of RRB significantly increased the mixing tolerance index (MTI). According to rheofermentometer analysis, the values of H'm, $T^{\prime}_1$, and retention volume decreased with increase in the amount of RRB added. According to the rapid visco analyzer (RVA) analysis, peak viscosity, holding strength, and setback values were greater in the control than in the RRB-containing samples. The addition of RRB to the flour influenced rheological properties like fermentation volume and acidity. The total acidity increased with the increase in the amount of RRB added. The present study has indicated that there was no significant difference between the rheological properties of the control and 5% RRB-containing dough samples. Therefore, the addition of 5% RRB could be an effective way to produce functional flour bread without affecting its desirable physical properties.

• Food Science and Industry
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• v.52 no.3
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• pp.261-271
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• 2019

Gut microbiome have recently provided evidence that the gut microbiota are capable of greatly influencing all aspects of physiology and immunology. Although a number of recent studies have shown that probiotics can modulate gut microbiota structure, the mechanism underlying this effect remains to be elucidated. In a disease state, the relative abundances of beneficial gut bacteria are generally reduced, which is restored by constant probiotic supplementation. Oral administration of probiotics improved the disease state by (1) inducing differentiation and function of regulatory T cells, (2) reducing inflammatory response, (3) modulating the gut environment, and (4) increasing the proportions of short-chain fatty acid- or beneficial metabolite-producing gut microbiota including the genera Bifidobacterium, Faecalibacterium, Akkermansia, etc. In this review, current knowledge on how probiotics can influence host's health by altering gut microbiota structure and on how probiotics and beneficial gut bacteria can be applied as next-generation probiotics will be discussed.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.3
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• pp.15-25
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• 2019

The study was conducted to compare the chemical properties and microbial activity of soil and the crop productivity by applying homemade liquid fertilizers (LF) used in leading cucumber farms as well as to evaluate the eco-friendly LFs to substitute for a chemical fertilizer. Three homemade LFs, EM, starfish, and native microbes, and a chemical LF were regularly fertigated per three days during the growing season. Chemical LF contained the highest pH, EC (electrical conductivity), and concentrations of T-N, $P_2O_5$, K, Ca, and Mg, while the lowest EC level was observed for EM LF. Soil EC was the highest to the 3.0 dS/m for chemical LF-plots, with lowering soil pH, OM (organic matter), and Mg concentration. Soil chemical properties mostly increased in native microbes LF-plots. However, soil microbial properties were not significantly different among the LF treatment plots. OTU (operational taxonomic units), richness estimator, and diversity index of bacteria and fungi increased in the chemical LF and EM LF based on the pyrosequencing analysis. SPAD and PS II values on the treated-cucumber leaves were seasonally decreased from 32 to 60 days after transplanting, with the rapid decline observed at 45 days after transplanting. Number of leaves and crop height increased in the treatments with EM and native microbes LF. LF treated-cucumber crops were not significantly different for total fresh weight and fruit yield.

• Journal of the Korean Society for Heat Treatment
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• v.32 no.5
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• pp.212-223
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• 2019

This study is to investigate the relationship between microstructural factors and tensile properties after aging heat treatment of the 15-5PH stainless steel at the temperature range of $450^{\circ}C$, $500^{\circ}C$ and $550^{\circ}C$ for various time. For the aging time of 2 hours, hardness showed maximum at $450^{\circ}C$ and then decreased with increasing aging temperature. While, hardness decreased gradually during aging $450^{\circ}C$, $500^{\circ}C$ and $550^{\circ}C$ from 1 hour to 5 hours but the hardness nearly unchanged until the 100 hours after 5 hours aging. When aging at $450^{\circ}C$, Cu atoms preferentially aggregated at the prior austenite grain boundaries and martensite lath boundaries, and Cu concentration at those boundaries was nearly unchanged even after aging for 100 hours. Therefore it was suggested that the coherency is still maintained after 100 hours aging at $450^{\circ}C$. Aging at $500^{\circ}C$ and $550^{\circ}C$ results in an increase in the concentration of Ni at the martensite lath boundaries and prior austenite grain boundaries, resulting in the formation of reversed austenite. Especially, when aged at $550^{\circ}C$ for 100 hours, the concentration of Ni remarkably increased at those boundaries, and thus the microstructure of herring bone shape was appeared. Considering the migration of Ni atom to the lath boundaries and prior austenite grain boundaries, Ni atoms contributed greatly to the formation of reversed austenite. On the other hand, it was found that Cu atoms hardly moving to those boundaries may not be contributed to the formation of reversed austenite. When aging at $450^{\circ}C$, the coarsening of the precipitated Cu atoms proceeded very slowly with increasing aging time, therefore the decrease in strengths were small but the reduction area was considerably increased due to the softening of the matrix. At the aging temperature of $500^{\circ}C$ and $550^{\circ}C$, the strengths decreased and the elongation and reduction area increased due to the appearance of the reversed austenite. Especially, the increase of reduction area was remarkable.