• Journal of Dental Anesthesia and Pain Medicine
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• 제18권1호
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• pp.9-17
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• 2018

Background: The structure and function of bone tissue is maintained through a constant remodeling process, which is maintained by the balance between osteoblasts and osteoclasts. The failure of bone remodeling can lead to pathological conditions of bone structure and function. Remifentanil is currently used as a narcotic analgesic agent in general anesthesia and sedation. However, the effect of remifentanil on osteoclasts has not been studied. Therefore, we investigated the effect of remifentanil on pre-osteoclast (pre-OCs) differentiation and the mechanism of osteoclast differentiation in the absence of specific stimulus. Methods: Pre-OCs were obtained by culturing bone marrow-derived macrophages (BMMs) in osteoclastogenic medium for 2 days and then treated with various concentration of remifentanil. The mRNA expression of NFATc1 and c-fos was examined by using real-time PCR. We also examined the effect of remifentanil on the osteoclast-specific genes TRAP, cathepsin K, calcitonin receptor, and DC-STAMP. Finally, we examined the influence of remifentanil on the migration of pre-OCs by using the Boyden chamber assay. Results: Remifentanil increased pre-OC differentiation and osteoclast size, but did not affect the mRNA expression of NFATc1 and c-fos or significantly affect the expression of TRAP, cathepsin K, calcitonin receptor, and DC-STAMP. However, remifentanil increased the migration of pre-OCs. Conclusions: This study suggested that remifentanil promotes the differentiation of pre-OCs and induces maturation, such as increasing osteoclast size. In addition, the increase in osteoclast size was mediated by the enhancement of pre-OC migration and cell fusion.

• 한국초등과학교육학회지:초등과학교육
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• 제41권4호
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• pp.725-739
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• 2022

본 연구는 AR 기술을 활용하여 안내된 과학탐구 프로그램을 개발함에 있어서 초등 예비교사들이 무엇에 중점을 두었으며, 어떠한 어려움을 겪었는지 분석하고, 이를 토대로 예비교사의 역량 함양 및 양성교육을 위한 시사점을 제공하는 데 목적이 있다. 이를 위하여 AR 기반 안내된 탐구 프로그램을 개발하는 강의에 참여한 초등 예비교사들의 사례를 수집하고 그들이 중점을 둔 부분과 겪은 어려움을 프로그램 '설계 단계'와 '제작 단계'로 범주화하여 분석하였다. 분석 결과, 프로그램 설계 단계에서 예비교사들은 능동적인 탐구과정을 촉진하는 시나리오를 구성하고, 동시에 AR 기술이 지닌 고유의 행위유도성으로서 3D 환경의 생생한 시각 자료를 구성하여 가상세계와 실세계에서의 탐구 경험을 의미 있게 연결짓는 데에 중점을 두었다. 또한 예비교사들은 시나리오의 설계, 탐구 프로그램 개발을 위한 정보 수집, 초등학생의 능동적 관찰을 이끄는 방법구현에 어려움을 경험하였으며, 탐구에 대한 근본적 의문으로 어려움을 겪었다. 또한 예비교사들은 AR 기술의 장점을 살리는 것을 어려워하였으며, 컨텐츠 제작 프로그램인 CoSpaces에 대한 배경지식이 부족하여 탐구 프로그램을 구상하는 데에 어려움을 겪었다. 프로그램 제작 단계에서는 초등학생들이 탐구에 집중할 수 있는 환경을 조성하기 위해, 예비교사들은 프로그램 조작을 쉽고 단순하게 구성하고자 했으며, 게임적 요소나 쌍방향적 상호작용 요소를 추가하여 학습자의 흥미를 높일 방법에 중점을 두었다. 또한 CoSpaces를 이용한 프로그래밍 과정에서 어려움을 겪었다. 이러한 결과를 바탕으로 예비교사 역량 함양 및 교사양성교육 방안 모색을 위한 시사점에 대해 논의하였다.

• 한국식품저장유통학회지
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• 제31권2호
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• pp.210-217
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• 2024

This study aimed to compare the quality of smoked fish products processed with liquid smoke with and without pre-cooking when stored at room temperature (25℃) for 0, 2, 4, and 6 days. The observations included moisture content, water holding capacity, color, and total plate and mold counts. The treated samples were also analyzed for polyhydroxyaromatic hydrocarbons (PAHs) at day 0. The study found that the pre-cooked products had a lower moisture content (55.1%) than the control (59.9%) during storage. Additionally, the pre-cooked product had a higher water holding capacity than the control. The TPC value indicates that the pre-cooked product meets the Indonesian standard for smoked fish up to the 2nd day of storage, whereas the control product only meets the standard on day 0. However, the total mold of the control products meets the Indonesian standard until the 2nd day of storage, while the pre-cooked products only meet the standard on day 0. The pre-cooked product had a higher lightness value (L^*) than the control. The analysis of polyhydroxy aromatic hydrocarbon (PAH) showed that the pre-cooking process did not affect the concentration of PAH.

• Asian-Australasian Journal of Animal Sciences
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• 제3권4호
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• pp.343-346
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• 1990

A study was conducted to determine the effect of prostaglandin $F_2$ alpha ($PGF_2$ alpha) on the reaction time and seminal characteristics of buffalo bulls. Semen was collected from three Murrah bulls in three periods: pre-treatment, treatment and post-treatment. During the treatment period each bull was administered 2 ml $PGF_2$ alpha (Synchrocept, Fenprostalene) im, 1 hour prior to semen collection. In the post-treatment, semen was collected 7 days after the last injection of $PGF_2$. Semen samples were evaluated immediately after collection. Pre-collection injection of $PGF_2$ alpha has no significant effect on reaction time, semen volume, percentage motility, sperm concentration and total number of sperms per ejaculate. Fluctuations in semen color and consistency were observed. There is a significant (p<0.05) increase in the mean percentage of normal spermatozoa during the treatment and post treatment periods. Likewise, administration of PG results into a significant (p<0.05) rise on the average percentage of live sperms but this effect was not manifested in the post-treatment period. Improvement in mass activity was observed during the treatment and post-treatment periods.

• 한국물환경학회지
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• 제26권5호
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• pp.810-815
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• 2010

Ultrasonic sludge pre-treatment has been studied to enhance the performance of anaerobic digestion by increasing sludge hydrolysis which is regarded as the rate-limiting-step of anaerobic digestion. In this study, the effect of ultrasonic pre-treatment on sludge hydrolysis (solubilization) and methane production was investigated. Sludge solubilization efficiency increased with ultrasonic energy input. However, it is uneconomical to apply more than 720 kJ/L as the solubilization efficiency per energy input declines afterwards. Volatile fatty acids concentration increased after the ultrasonic sludge hydrolysis. Anaerobic batch digestion showed that methane volume reached 64.7 and 84.5 mL after 18 days of incubation with the control sludge and ultrasonically hydrolyzed sludge, respectively. Methane production potential, maximum methane production rate, and the lag time of modified Gompertz equation were changed from 70 mL, 6.4 mL/day, and 1.2 days to 89 mL, 9.6 mL/day, and 0.5 day, respectively, after the ultrasonic sludge treatment. The results proved that ultrasonic pre-treatment contributed significantly not only for the methane production but also for the reduction of anaerobic digestion time which is critical for the performance of anaerobic sludge digestion.

• 한국발생생물학회지:발생과생식
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• 제14권1호
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• pp.1-5
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• 2010

We investigated the androgenic effects of 11-ketotestosterone (11-KT) on gonadal sex reversal and spermatogenesis in honeycomb grouper Epinephelus merra by method of gonadal biopsy. 11-KT was injected intramuscularly at a concentration of 1 and $10{\mu}g$ body weight. The proportion of cross sectional area of the gonad occupied by each germ cell type was measured and compared pre- and post-injection group. During the sex change phase, the distribution ratio of oocytes was decreased in all fish of 11-KT treatment group while the distribution ratio of spermatocytes was increased than pre-injection group. In male phase, all fish of 11-KT treatment group shown the increased distribution ratio of spermatocytes, but the distribution ratio of spermatozoa was decreased than pre-injection group. The present results suggest that 11-KT can stimulate degeneration of oocytes, proliferation of spermatocytes and spermiation in honeycomb grouper.

• 대한기계학회논문집B
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• 제31권6호
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• pp.499-506
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• 2007

This study aims to propose evaluation methods of chemical washing performance and estimate the washing capability by flowing detergent/water solution for application to home appliances such as dishwashers. Standard pollutant is stearic acid. A numerical study is also tried using a SIMPLER code. Preliminary experiments are performed by varying the concentration and temperature of the solution. From the pre-experiments, 10 minute pre-curing time is found to be necessary to remove the stearic acid. Stoichiometric ratio and detergent consumption coefficient of reaction between the detergent and stearic are estimated following a proposed method. Washing experiments of pollutant to compare with the numerical results are performed. The relative errors between the experimental and the numerical results with pre-curing time included are less than 7%. In conclusion, important mechanisms of chemical washing are revealed and methods of predicting washing performance are well established.

• Natural Product Sciences
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• 제23권4호
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• pp.247-252
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• 2017

The methylglyoxal (MGO) trapping constituents from onion (Allium cepa L.) peels were investigated using pre-column incubation of MGO and crude extract followed by HPLC analysis. The peak areas of MGO trapping compounds decreased, and their chemical structures were identified by HPLC-ESI/MS. Among major constituents in outer scale of onion, 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (2) was more effective MGO scavenger than quercetin (6) and its 4'-glucoside, spiraeoside (3). After 1 h incubation, compound 2 trapped over 90% MGO at a concentration of 0.5 mM under physiological conditions, but compounds 3 and 6 scavenged 45%, 16% MGO, respectively. HPLC-ESI/MS showed that compound 2 trapped two molecules of MGO to form a di-MGO adduct and compounds 3 and 6 captured one molecule of MGO to form mono-MGO adducts, and the positions 6 and 8 of the A ring of flavonoids were major active sites for trapping MGO.

• 한국토양비료학회지
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• 제48권3호
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• pp.213-217
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• 2015

Soil moisture shortage can reduce yield of waxy corn because maize is one of the sensitive crops to the drought stress. Farmers cannot irrigate due to limited water resource and irrigating facilities although applying water is the most effective practice to solve the drought problem. The study was conducted to investigate the pre-treatment effect of salicylic acid on reducing drought damage of waxy corn (Zea mays L.). Salicylic acid at concentration of 0.2 mM was applied at seven-leaf stage or ten-leaf stage three times. Drought stress was imposed by withholding irrigation from 11 days before anthesis to 10 days after anthesis. Application of salicylic acid significantly increased ear length by 11.0~12.3% and yield by 8.8~11.3% compared with non-treated control, indicating that the drought injuries of waxy corn can be alleviated through pre-treatment of salicylic acid at the vegetative stage.

• 기본간호학회지
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• 제11권3호
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• pp.344-352
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• 2004

Purpose: The purpose of this study was to identify the effect of aroma therapy on exam syndromes and temporary fatigue of senior high school students who are preparing to take college entrance exams. Method: This study was a pre-experimental research using a one-group pre-post test design and was conducted between April and July 2003 with 35 high school students. A pre-post test was used to measure long-term exam syndromes and temporary fatigue during the first period of school. Paired t-test was used. Aromas were given using an aroma electrical lamp, aroma necklet with basic oils of rosemary and lemon. According to the condition of the students, one or two oils were added: peppermint, pine, eucalyptus and Clary-Sage. Results: After two months (May, June), the result of administering aroma therapy to senior high school students showed in June there was a decrease in principal exam syndromes such as eye fatigue, headache, shoulder pain, neck stiffness, back pain, and common cold, and there was an increase Un study concentration during the two months. However, in May, there were no significant effects. The reason may have been a strong extraneous factor from midterm exams that would affect their college entrance. Conclusion: According to these results, if we use aroma oil carefully, with evidence-based applications, aroma therapy can have a positive effect on senior high school students who are preparing for the college entrance exams.