• BMB Reports
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• 제41권3호
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• pp.259-265
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• 2008

Three peroxidase (POD) cDNAs were isolated from dehydration-treated fibrous roots of sweetpotato (Ipomoea batatas) plant via the screening of a cDNA library, and their expressions were assessed to characterize functions of each POD in relation to environmental stress. Three PODs were divided into two groups, designated the basic PODs (swpb4, swpb5) and the anionic PODs (swpa7), on the basis of the pI values of mature proteins. Fluorescence microscope analysis indicated that three PODs are secreted into the extracellular space. RT-PCR analysis revealed that POD genes have diverse expression patterns in a variety of plant tissues. Swpb4 was abundantly expressed in stem tissues, whereas the expression levels of swpb5 and swpa7 transcripts were high in fibrous and thick pigmented roots. Swpb4 and swpa7 showed abundant expression levels in suspension cultured cells. Three POD genes responded differently in the leaf and fibrous roots in response to a variety of stresses including dehydration, temperature stress, stress-associated chemicals, and pathogenic bacteria.

• Journal of Plant Biotechnology
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• 제50권
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• pp.76-81
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• 2023

As cultured plant cells can grow in high oxidative stress conditions, they form an excellent system to study antioxidant mechanisms and the mass production of antioxidants. Oxidative stress is a major cause of damage in plants exposed to various types of environmental stress, including heavy metals, such as cadmium (Cd). Heavy metal accumulation can interfere with many cell functions and plant growth. To evaluate the contribution of oxidative stress to Cd-induced toxicity, cultured sweetpotato (Ipomoea batatas) cells were treated with increasing concentrations of Cd (0, 10, 25, and 50 μM) and cultured further. Cell growth was significantly inhibited by 25 and 50 μM of Cd, and the total protein content increased with 50 μM of Cd. Additionally, the activity of peroxidase (POD) and ascorbate peroxidase (APX), antioxidant enzymes that remove hydrogen peroxide (a reactive oxygen species), increased in the cells after treatment with 50 μM of Cd. The expression analysis of POD, APX, and peroxiredoxin (PRX) isolated from sweetpotato cultured cells in a previous study revealed the differential expression of POD in response to Cd. In this study, the expression levels of several acidic POD (swpa2, swpa3, and swpa4) and basal POD (swpb1, swpb2, and swpb3) genes were increased in Cd-treated cultured cells. These results indicate that Cd-mediated oxidative stress is closely linked to improved POD-mediated antioxidant defense capacity in sweetpotato suspension-cultured cells.

• 한국기계가공학회지
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• 제4권4호
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• pp.48-53
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• 2005

This research is materialized the mechanism of a interlocking elevator device to meet with customer's requirement demanding a variety of function. On this suitably theoretical translation and by considering of material significance of the most factor's tension spring and torsion spring, it's compared and reviewed the stress's calculation according that SWC and SWPB applied differently. And also that is approved through actual experiment. Out of a variety of feasible movement. Torque Balance is materialized by combination of tension spring, torsion spring and disk spring. So that application of 3 factors for optimal design is very important factor. In future, this research thesis make sure to play a highly role for application and improvement mechanically in various industry sector out of materializing interlock.

• 한국기계가공학회지
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• 제6권1호
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• pp.13-19
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• 2007

The spring is an important mechanical parts to improve the functions of precision machines, automobiles, ships, industrial machines, and IT devices etc.. The hinge mechanism for LCD monitors is very important to support and maintain the proper position of monitor panel, and the tension spring which is a major parts of hinge mechanism plays a significant roll to provide the supporting force positioning the monitor panel. In this paper, an analysis and experiment were carried out to investigate the fatigue characteristics of the tension spring of hinge mechanism, such as hardness test, fatigue test and fractography analysis. As a result of this study the SWPB with heat treatment and shot peening was found to have the optimal design conditions of tension spring for LCD monitor hinge mechanism.

• 한국심리학회지:학교
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• 제17권2호
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• pp.165-180
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• 2020

본 연구의 목적은 다층적 행동지원 모형을 적용하고 있는 학교차원 긍정적 행동지원(School-Wide Positive Behavior Supports, SWPBS)을 국내 학교현장에서 근거기반 실천으로 보급하기 위해 개별화지원에 해당하는 3차 지원의 실행충실도 평가도구를 개발해 타당화하는 것이었다. 3차 지원 실행충실도 평가도구를 개발하기 위해 문헌 개관 및 전문가 내용 타당도 검증을 통해 핵심 평가요소 6개 요인으로 구성된 37개의 예비문항을 선정하였다. 이후 학교차원 긍정적 행동지원 실행 경험이 있는 현직 교사 185명(남 52명, 여 133명)을 대상으로 3차 지원 실행충실도 척도, 개별화지원 척도, 학교풍토 척도, 학생지도 척도, 긍정적 행동지원 효과성 척도로 구성된 설문지를 배포해 자료를 수집하였다. 탐색적 요인분석에서 각 하위요인에 4문항으로 구성된 5요인 구조(요인 1: 개별화지원 계획의 점검 및 평가, 요인 2: 정신건강 서비스 연계를 통한 지원, 요인 3: 위기관리 계획, 요인 4: 문제행동 평가, 요인 5: 개별화지원 팀구성)의 총 20문항이 최종 문항으로 선정되었다. 또한 내적 합치도는 전체 문항 α=.950, 하위요인은 α=.888 ~ .954로 모두 양호하였다. 상관분석에서 3차 지원 실행충실도 척도는 개별화지원 척도, 학교풍토 척도, 학생지도 척도, 긍정적 행동지원 효과성 척도와 각각 유의미한 상관을 나타내면서 양호한 수렴타당도를 나타내었다. 마지막으로, 확인적 요인분석에서 5요인 구조의 모형 적합도는 양호하였고, 신뢰도 및 타당도가 안정적인 것으로 나타났다. 따라서 SWPBS의 실행충실도를 점검하고 평가하는 데 본 척도가 신뢰롭고 타당하게 사용될 수 있을 것으로 보인다. 또한 한국형 3차 지원 실행충실도 척도가 국내 학교현장에서 SWPBS를 근거기반의 행동적 개입으로 활용하는 데 기여할 수 있을 것이다.