• 한국식품영양과학회지
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• 제28권1호
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• pp.233-239
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• 1999

This study was performed to evaluate the effects of the supplementation of lactic acid bacterias (LAB; S. thermophilus, L. acidophilus) aluminum accumulation and function kidney in rats treated with 250 g/g aluminum sulfate for 4 weeks. Fifty male Sprague Dawley strains were divided into five groups according to the types of supplement. the control, S. thermophilus culture group(A), autoclaved S. thermophilus culture(B), L. acidophilus culture group(C) and autoclaved L. acidophilus(D). The weight gain was increased by supplementation of S. thermophilus culture(A), autoclaved S. thermophilus culture(B), L. acidophilus culture(C), autoclaved L. acidophilus culture(D), especially by supplementation of S. thermophilus cultured(A) as compared to control group. The amount of water intake was increased in control group as compared to the LAB supplemented group. The content of aluminum were decreased 19.57%, 31.25%, 37.10%, and 32.40% in kidney after supplementation of non autoclaved culture group (A,C), and autoclaved group(B,D) respectively, as compared to control group. Water balance, urine volume, and excretion of sodium and potassium decreased in LAB supplemented group and control group. Excretion of creatinine increased in control group and tendency to increased in LAB supplemented group. In conclusion, the effect of suppression of aluminum accumulation was more effective in sup plementation of S. thermophilus culture(A), and L. acidophilus culture(C) than autoclaved S. thermo philus culture(B), and L. acidophilus culture(D).

• 대한안전경영과학회지
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• 제24권4호
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• pp.33-39
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• 2022

Safety has once again emerged as a social issue due to the enforcement of the Serious Disasters Punishment Act and the occurrence of major disasters recently. As such, the safety culture related to unsafe human behavior is drawing attention as various discussions about the importance of safety and accident prevention are currently being undertaken. This study aims to determine whether changes in the level of safety culture in companies affect the accident rate. To this end, we targeted three workplaces in the same company in the domestic manufacturing industry, and 2,790 people were surveyed using DNV's Safety Will(ISRS-C version 4.0) for safety culture level diagnosis. The change in safety culture level and accident rate were compared and analyzed after carrying out safety culture level improvement activities for 5 years. As a result, the level of safety culture increased by 5.8 points, an overall improvement of 9.5%, while the total number of accidents decreased by 20%, from 5 to 4, indicating a general decreasing trend in accident occurrence. Results confirmed that the change in the level of safety culture affects the accident rate, and the improvement in the level of safety culture affects a reduction in accidents. Therefore, this study suggests that efforts to improve the level of safety culture within a company can be associated with accident reduction and accident prevention outcomes.

• 한국과학교육학회지
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• 제43권1호
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• pp.37-47
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• 2023

본 연구에서는 과학 수업 전문성과 관련된 변인들 간의 영향을 살펴보기 위하여 외적 변인인 학습조직문화를 외생변인으로, 내적 변인인 과학 인식론적 신념, 과학 교수 효능감을 내생 변인으로 설정하고 변인들 간의 직·간접적인 효과와 구조적 관계를 파악하고자 하였다. 서울과 경기 지역에서 과학을 가르치는 현직 초등교사 499명의 설문지 응답 결과를 데이터로 분석한 결과는 다음과 같다. 첫째, 본 연구에서 측정한 학습조직문화, 과학 인식론적 신념, 과학 교수 효능감 및 과학 수업 전문성과의 관계에 대한 상관을 살펴보면, 각 측정요인 간의 상관은 모두 유의한 상관계수를 보였다. 둘째, 과학 인식론적 신념과 과학 교수 효능감은 과학 수업 전문성에 직접 영향을 미치는 것으로 나타났다. 셋째, 과학 인식론적 신념은 과학 교수 효능감에 직접적으로 영향을 미치며, 과학 교수 효능감을 매개하여 과학 수업 전문성에도 유의한 영향을 나타냈다. 넷째, 교사가 지각한 학습조직문화는 과학 수업 전문성에 유의한 영향을 보이지 않았으나, 과학 인식론적 신념과 과학 교수 효능감에는 직접적으로 유의한 영향을 미치는 것으로 나타났다. 학습조직문화, 과학 인식론적 신념, 과학 교수 효능감, 과학 수업 전문성의 구조적 관계를 규명한 연구 결과를 토대로 초등교사의 과학 수업 전문성의 효율적인 향상을 위해 교사 개인의 내적 요인과 함께 학교 조직문화의 개선에 대한 방안도 고려할 필요성이 있음을 제안하였다.

• Reproductive and Developmental Biology
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• 제33권3호
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• pp.171-177
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• 2009

Spermatogonial stem cells(SSCs) only are responsible for the generation of progeny and for the transmission of genetic information to the next generation in male. Other in vitro studies have cultured SSCs for proliferation, differentiation, and genetic modification in mouse and rat. Currently, information regarding in vitro culture of porcine Germline Stem Cell(GSC) such as gonocyte or SSC is limited and is in need of further studies. Therefore, in this study, we report development of a successful culture system for gonocytes of neonatal porcine testes. Testis cells were extracted from $10{\sim}14$-day-old pigs. These cells were harvested using enzymatic digestion, and the harvested cells were purified with combination of percoll, laminin, and gelatin selection techniques. The most effective culture system of porcine gonocytes was established through trial experiments which made a comparison between different feeder cells, medium, serum concentrations, temperatures, and $O_2$ tensions. Taken together, the optimal condition was established using C166 or Mouse Embryonic Fibroblast(MEF) feeder cell, Rat Serum Free Medium(RSFM), 0% serum concentration, $37^{\circ}C$ temperature, and $O_2$ 20% tension. Although we discovered the optimal culture condition for proliferation of porcine gonocytes, the gonocyte colonies ceased to expand after one month. These results suggest inadequate acquirement of ingredients essential for long term culture of porcine GSCs. Consequently, further study should be conducted to establish a successful long-term culture system for porcine GSCs by introducing various growth factors or nutrients.

• Journal of Veterinary Science
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• 제24권1호
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• pp.4.1-4.16
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• 2023

Background: In vitro culture of preantral follicles is a promising technology for fertility preservation. Objectives: This study aims to investigate an optimized three-dimensional (3D) fetal bovine serum (FBS)-free preantral follicle culture system having a simple and easy operation. Methods: The isolated follicles from mouse ovaries were randomly divided in an ultra-low attachment 96-well plates supplement with FBS or bovine serum albumin (BSA) culture or encapsulated with an alginate supplement with FBS or BSA culture. Meanwhile, estradiol (E₂) concentration was assessed through enzyme-linked immunosorbent assay of culture supernatants. The diameter of follicular growth was measured, and the lumen of the follicle was photographed. Spindle microtubules of oocytes were detected via immunofluorescence. The ability of oocytes to fertilize was assessed using in vitro fertilization. Results: The diameters were larger for the growing secondary follicles cultured in ultra-low attachment 96-well plates than in the alginate gel on days 6, 8, and 10 (p < 0.05). Meanwhile, the E2 concentration in the BSA-supplemented medium was significantly higher in the alginate gel than in the other three groups on days 6 and 8 (p < 0.05), and the oocytes in the FBS-free system could complete meiosis and fertilization in vitro. Conclusions: The present study furnishes insights into the mature oocytes obtained from the 3D culture of the preantral follicle by using ultra-low attachment 96-well plate with an FBS-free system in vitro and supports the clinical practices to achieve competent, mature oocytes for in vitro fertilization.

• 한국문화재보존과학회:학술대회논문집
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• 한국문화재보존과학회 2007년도 제25회 학술대회발표 논문집
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• pp.44-45
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• 2007

• 한국문화재보존과학회:학술대회논문집
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• 한국문화재보존과학회 2007년도 제26회 추계학술대회
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• pp.67-69
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• 2007

• 복식문화학회:학술대회논문집
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• 복식문화학회 2001년도 International Costume Culture Conference
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• pp.81-81
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• 2001

• 복식문화학회:학술대회논문집
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• 복식문화학회 2001년도 International Costume Culture Conference
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• pp.65-65
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• 제19권9호
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• pp.1314-1321
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• 2006

The objective of this work was to study the effect of mixed culture solid substrate fermentation of C. tropicalis ZD-3 with A. niger ZD-8 on detoxification of cottonseed meal (CSM), and to investigate the effect of fermentation period, proportion of CSM in substrate, sodium carbonate, minerals and heat treatment on the reduction of free gossypol levels during mixed culture solid substrate fermentation of CSM. Experiment 1: Three groups of disinfected CSM substrate were incubated for 48 h after inoculation with either of the fungi C. tropicalis ZD-3, A. niger ZD-8 or mixed culture (C. tropicalis ZD-3 with A. niger ZD-8). One non-inoculated group was used as the control. Levels of initial and final free gossypol (FG), CP and in vitro CP digestibility were assayed. The results indicated that mixed culture fermentation was far more effective than single strain fermentation, which not only had higher detoxification rate, but also had higher CP content and in vitro digestibility. Experiment 2: CSM substrates were treated according to experimental variables including fermentation period, proportion of CSM in substrate, sodium carbonate, minerals and heat treatment, Then, the treated CSM substrates were inoculated with mixed culture (C. tropicalis ZD-3 with A. niger ZD-8) and incubated at $30^{\circ}C$ for 36 h in a 95% relative humidity chamber. After fermentation ended, FG and CP content of fermented CSM substrate was assayed. The results showed that the appropriate fermentation period was 36 h, and the optimal proportion of CSM in substrate was 70%. Addition of sodium carbonate to CSM substrate was beneficial for fermentative detoxification. Heat treatment could facilitate fermentative detoxification, and supplementation with minerals was instrumental in reducing gossypol levels during mixed culture solid substrate fermentation of CSM.