• 한국약용작물학회지
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• 제22권4호
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• pp.306-312
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• 2014

Endophytes are microorganisms that live in the internal tissues of plants without harming the host plants. In this symbiotic relationship, the host plants provide nutrients and shelter to the endophytes, in turn, endophytes can promote the growth of host plants and act as a biological control agents against plant pathogens. Plant-microbe interactions like this are noted for natural methods for sustainable agriculture and environmental conservation. However, in spite of the infinite potential, there are only a few reports on the endophytes present in ginseng. In this study, we isolated and identified the endophytes from Panax ginseng seeds and evaluated the biological activities (IAA production ability, nitrogen fixation ability, phosphate solubilization capacity, siderophore production ability, and antifungal activities) of the endophyte isolates. Eight different endophytes were identified by 16S rRNA sequencing. Most of the endophytes have antibiotic and plant growth promoting (PGP) activities. Particularly, PgSEB5-37E have the highest antibiotic activity, both PgSEB5-37B and PgSEB5-37H have high PGP traits such as an abilities to produce IAA, solubilize phosphate and fix nitrogen. These results indicated that the endophytes from P. ginseng seeds may have applicable value to many industries. In order to use the isolated endophytes, quantitative analysis and field tests are needed to be performed.

• 한국전문물리치료학회지
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• 제21권4호
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• pp.56-66
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• 2014

For maintaining adequate psychometric properties when reducing the number of items from an instrument, item level psychometrics is crucial. Strategies such as low item correlation or factor loadings, using classical test theory, have traditionally been advocated. The purpose of this study is to describe the development of a new short form assessing the impact of low back pain on physical activity. Rasch measurement model has been applied to the International Classification of Functioning, Disability and Health Activity Measure (ICF-AM). One hundred and one individuals with low back pain aged 19-89 years (mean age: $48.1{\pm}17.3$) who live in the community were participated in the study. Twenty-seven items of lifting/carrying construct of the ICF-AM were analyzed. Ten items were selected from the construct to create a short form. Item elimination criteria include: 1) high or low mean square (out of the range: .6-1.4 for the fit statistics), 2) similar item calibrations to adjacent items, 3) person separation value, and item-person map for potential gap in person ability continuum. All 10 items of the short form fit to the Rasch model except one item (i.e., carrying toddler on back). Despite its high infit and outfit statistics (1.90/2.17), the item had to be reinstated due to potential gaps at the upper extreme of person ability level. The short form had a slightly better spread of person ability continuum compared to the entire set of item. The created short form separated individuals with low back pain into nearly 4 groups, while the entire set of items separated the individuals into 6 groups. The findings prompted multidimensional models for better explanation of the lifting/carrying domain. The item level psychometrics based on the Rasch model can be useful in developing short forms with rationally retained items.

• 대한물리의학회지
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• 제6권3호
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• pp.311-321
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• 2011

Purpose : The purpose of this study was to determine effect of Medical Exercise therapy on walking ability and ankle muscles activation after stroke. Method : Participants were randomly divided into either MET training group(n=12) and control group(n=12). All of participants had been receving a traditional rehabilitation program, 5 days a week. MET training group have additionally undergone for six weeks, 3 days a week, the MET program. But control group was not received any additional program except the traditional rehabilitation program. The 10 mWT, F8WT and 2 MWT to measure walking ability were carried out twice before and after training. Muscular activity of the ankle was estimated by analyzing the RMS of action potential for EMG in terms of tibialis anterior muscle(TA), soleus(SO), gastrocnemius medial head(GM), gastrocnemius lateral head(GL). Rresults : At the walking ability, MET training group demonstrated a significant improvememt in the score of the 10 mWT(p<0.001), 2 MWT(p<0.05), but F8WT was not significant improvement(p>0.05). At the ankle muscle activation, MET training group demonstrated a significant improvememt in the RMS of the TA(p<0.01) and SO(p<0.05) but GM(p>0.05) and GL(p>0.05) were not significant improvement. Conclusion : From these results of this study, MET training for 6 weeks has an effect on improvement of walking ability and ankle muscles activation after stroke.

• 한국학교ㆍ지역보건교육학회지
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• 제23권4호
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• pp.17-28
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• 2022

Objectives: This study aimed to provide the measures for improving the self-directed learning ability and the reference data for substantializing the educational programs by verifying the main factors affecting the self-directed learning ability of dental hygiene students in reality when the learners' autonomy is emphasized than ever. Methods: From June 20 to July 4, 2022, an online survey was conducted targeting total 218 dental hygiene students. The collected data was analyzed by using the SPSS Program Version 22.0. Results: First, in the results of analyzing differences in detailed items of self-directed learning ability according to the general characteristics, the 'students who entered the department of dental hygiene by considering their aptitude and interest' showed higher results than the 'students who entered the department by considering their high school record'. Second, when the academic efficacy, study immersion, and problem-solving ability of dental hygiene students were higher, their self-directed learning ability was also high. Third, the factor that had the greatest effect on self-directed learning ability of dental hygiene students was problem-solving ability, which was followed by academic efficacy and study immersion. Conclusion: Putting together the results above, in order to cultivate the problem-solving ability of dental hygiene students, it would be necessary to operate the problem-solving-centered simulation course that could foster critical thinking, interactions with others, and creative approach and solution to problems in dental medical site. It would be also possible to improve their academic efficacy by applying the learning mentoring & one-to-one learning counseling program, and also strengthening proper feedbacks for learners. Moreover, the study immersion could be strengthened by developing and operating the emotion-based learning motivation program & learning coaching program through the process of verifying the potential and growth needs of learners, exploring one's own resources through learning diagnosis/introspection, and exploring the career-related vision for strengthening the learning motivation, which could have positive effects on the improvement of self-directed learning ability.

• The Korean Journal of Physiology and Pharmacology
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• 제24권3호
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• pp.223-232
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• 2020

Sesamin, a lipid-soluble lignin originally isolated from sesame seeds, which induces cancer cell apoptosis and autophagy. In the present study, has been reported that sesamin induces apoptosis via several pathways in human lung cancer cells. However, whether mitophagy is involved in sesamin induced lung cancer cell apotosis remains unclear. This study, the anticancer activity of sesamin in lung cancer was studied by reactive oxygen species (ROS) and mitophagy. A549 cells were treated with sesamin, and cell viability, migration ability, and cell cycle were assessed using the CCK8 assay, scratch-wound test, and flow cytometry, respectively. ROS levels, mitochondrial membrane potential, and apoptosis were examined by flow cytometric detection of DCFH-DA fluorescence and by using JC-1 and TUNEL assays. The results indicated that sesamin treatment inhibited the cell viability and migration ability of A549 cells and induced G₀/G₁ phase arrest. Furthermore, sesamin induced an increase in ROS levels, a reduction in mitochondrial membrane potential, and apoptosis accompanied by an increase in cleaved caspase-3 and cleaved caspase-9. Additionally, sesamin triggered mitophagy and increased the expression of PINK1 and translocation of Parkin from the cytoplasm to the mitochondria. However, the antioxidant N-acetyl-L-cysteine clearly reduced the oxidative stress and mitophagy induced by sesamin. Furthermore, we found that cyclosporine A (an inhibitor of mitophagy) decreased the inhibitory effect of sesamin on A549 cell viability. Collectively, our data indicate that sesamin exerts lethal effects on lung cancer cells through the induction of ROS-mediated mitophagy and mitochondrial apoptosis.

• 기술혁신학회지
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• 제14권spc호
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• pp.1232-1255
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• 2011

본 연구에서는 신제품 확산 모델 활용에 있어서 보다 적은 노력이 필요하지만 객관적이고 신속한 활용을 가능하게 만들어줄 모형을 제안한다. 기대주기 모델과 소비자 수용 모델이라는 이론적 배경을 바탕으로, 서지분석학과 초기 시장의 규모만으로 최대 잠재 시장을 추정해냄으로써 대표적인 확산 모형인 배스 모형(Bass model)에 필요한 주요 모수를 제공하는 방법을 제시했다. 모형의 예측력을 하이브리드자동차 사례를 통해 분석한 결과, 모형의 예측결과는 여러 가지 객관적인 정보를 통해 추정한 잠재 시장과 유사한 규모를 성공적으로 예측해 내어 모형의 활용 가능성을 확인할 수 있었다. 제안된 모형이 제공한 최대 잠재 시장은 다른 성장곡선모형에도 바로 적용 가능하다는 점을 볼 때 제안된 모형은 서지분석학을 통한 기술 확산 예측과 유망기술 탐색에 새로운 방향을 제시했다고 할 것이다.

• 한국미생물·생명공학회지
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• 제49권2호
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• pp.157-166
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• 2021

The probiotic market is constantly continuing to grow, concomitantly with a widening in the range and diversity of probiotic products. Probiotics are defined as live microorganisms that provide a benefit to the host when consumed at a proper dose; the viability of a probiotic is therefore of crucial importance for its efficacy. Many products undergo lyophilization for maintaining their shelf-life. Unfortunately, this procedure may damage the integrity of the cells due to stress conditions during both the freezing and (vacuum-) drying process, thereby impacting their functionality. We propose a lysine-based mixture for rehydration of freeze-dried probiotics for improving their viability during in vitro simulated gastric and duodenum stress conditions. Measurement of the zeta potential served as an indicator of cell integrity and efficacy of this mixture, while functionality was estimated by adhesion to a human enterocyte-like Caco-2 cell-line. The freeze-dried bacteria exhibited a significantly different zeta potential compared to fresh cultures; however, this condition could be restored by rehydration with the lysine mixture. Recovery of the surface charge was found to influence adhesion ability to the Caco-2 cell-line. The optimum lysine concentration of the formulation, designated "Zeta-bio", was found to be 0.03 M for improving the viability of Lactiplantibacillus plantarum Lp-115 by up to 13.86% and a 7-strain mixture (400B) to 41.99% compared to the control rehydrated with distilled water. In addition, the lysine Zeta-bio formulation notably increased the adherence ability of lyophilized Lp-115 to the Caco-2 cell-line after subjected to the in vitro stress conditions of the simulated gastrointestinal tract passage.

• Journal of Periodontal and Implant Science
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• 제52권6호
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• pp.437-454
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• 2022

Embryonic stem cells have been a popular research topic in regenerative medicine owing to their pluripotency and applicability. However, due to the difficulty in harvesting them and their low yield efficiency, advanced cell reprogramming technology has been introduced as an alternative. Dental stem cells have entered the spotlight due to their regenerative potential and their ability to be obtained from biological waste generated after dental treatment. Cell reprogramming, a process of reverting mature somatic cells into stem cells, and transdifferentiation, a direct conversion between different cell types without induction of a pluripotent state, have helped overcome the shortcomings of stem cells and raised interest in their regenerative potential. Furthermore, the potential of these cells to return to their original cell types due to their epigenetic memory has reinforced the need to control the epigenetic background for successful management of cellular differentiation. Herein, we discuss all available sources of dental stem cells, the procedures used to obtain these cells, and their ability to differentiate into the desired cells. We also introduce the concepts of cell reprogramming and transdifferentiation in terms of genetics and epigenetics, including DNA methylation, histone modification, and non-coding RNA. Finally, we discuss a novel therapeutic avenue for using dental-derived cells as stem cells, and explain cell reprogramming and transdifferentiation, which are used in regenerative medicine and tissue engineering.

• Journal of Microbiology and Biotechnology
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• 제34권6호
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• pp.1239-1248
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• 2024

Peatlands are marginal agricultural lands due to highly acidic soil conditions and poor drainage systems. Drought stress is a big problem in peatlands as it can affect plants through poor root development, so technological innovations are needed to increase the productivity and sustainability of upland rice on peatlands. Rhizobacteria can overcome the effects of drought stress by altering root morphology, regulating stress-responsive genes, and producing exopolysaccharides and indole acetic acid (IAA). This study aimed to determine the ability of rhizobacteria in upland rice to produce exopolysaccharides and IAA, identify potential isolates using molecular markers, and prove the effect of rhizobacteria on viability and vigor index in upland rice. Rhizobacterial isolates were grown on yeast extract mannitol broth (YEMB) medium for exopolysaccharides production testing and Nutrient Broth (NB)+L-tryptophan medium for IAA production testing. The selected isolates identify using sequence 16S rRNA. The variables observed in testing the effect of rhizobacteria were germination ability, vigour index, and growth uniformity. EPS-1 isolate is the best production of exopolysaccharides (41.6 mg/ml) and IAA (60.83 ppm). The isolate EPS-1 was identified as Klebsiella variicola using 16S rRNA sequencing and phylogenetic analysis. The isolate EPS-1 can increase the viability and vigor of upland rice seeds. K. variicola is more adaptive and has several functional properties that can be developed as a potential bioagent or biofertilizer to improve soil nutrition, moisture and enhance plant growth. The use of rhizobacteria can reduce dependence on the use of synthetic materials with sustainable agriculture.

• 과학교육연구지
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• 제39권3호
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• pp.376-388
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• 2015

본 연구에서는 초등 과학 영재들을 위한 과학 탐구 능력 평가 문항을 개발하고 이를 초등 과학 영재들에게 적용하여 그 활용성에 대해 살펴보고자 하였다. 과학 탐구 능력 평가 문항은 실험 기반의 형태로 '식물의 구조와 기능' 단원의 식물 관다발 구조에 대한 것으로 관찰 및 추리, 실험 설계, 결론 도출 영역으로 구성되어 있다. 그리고 평가 문항의 채점 기준은 관찰 및 추리 영역의 경우 쌍떡잎식물과 외떡잎식물의 관다발 배열과 구조, 물관의 위치, 잉크에 식물을 담가 두는 이유 등의 요소를 가지고 상세화하였다. 실험 설계 영역의 경우 식물해부 방법, 실험 과정 구성 등을 요소로, 결론 도출영역의 경우는 실험 결과에 대한 예상, 예상과 결과에 대한 비교와 검증 등으로 상세화하였다. 이렇게 개발된 과학 탐구 능력 평가 문항을 대학부설 과학영재교육원에서 교육받고 있는 22명의 초등 과학영재들에게 적용하였다. 그 결과 과학영재들에게 활용 가능성이 매우 높은 것으로 나타났다.