• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.48-48
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• 2011

We have developed a chemically-driven top-down approach using vapor phase HCl to form various GaN nanostructures and successfully demonstrated dislocation-free and strain-relaxed GaN nanostructures without etching damage formed by a selective dissociation method. Our approach overcomes many limitations encountered in previous approaches. There is no need to make a pattern, complicated process, and expensive equipment, but it produces a high-quality nanostructure over a large area at low cost. As far as we know, this is the first time that various types of high-quality GaN nanostructures, such as dot, cone, and rod, could be formed by a chemical method without the use of a mask or pattern, especially on the Ga-polar GaN. It is well known that the Ga-polar GaN is difficult to etch by the common chemical wet etching method because of the chemical stability of GaN. Our chemically driven GaN nanostructures show excellent structure and optical properties. The formed nanostructure had various facets depending on the etching conditions and showed a high crystal quality due to the removal of defects, such as dislocations. These structure properties derived excellent optical performance of the GaN nanostructure. The GaN nanostructure had increased internal and external quantum efficiency due to increased light extraction, reduced strain, and improved crystal quality. The chemically driven GaN nanostructure shows promise in applications such as efficient light-emitting diodes, field emitters, and sensors.

• The Plant Pathology Journal
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• 제36권6호
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• pp.515-535
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• 2020

Essential oils (EOs) have gained a renewed interest in many disciplines such as plant disease control and medicine. This review discusses the components of ginger EOs, their mode of action, and their potential nanotechnology applications in controlling tropical plant diseases. Gas chromatography-mass spectroscopy (GC-MS), high-performance liquid chromatography, and headspace procedures are commonly used to detect and profile their chemical compositions EOs in ginger. The ginger EOs are composed of monoterpenes (transcaryophyllene, camphene, geranial, eucalyptol, and neral) and sesquiterpene hydrocarbons (α-zingiberene, ar-curcumene, β-bisabolene, and β-sesquiphellandrene). GC-MS analysis of the EOs revealed many compounds but few compounds were revealed using the headspace approach. The EOs have a wide range of activities against many phytopathogens. EOs mode of action affects both the pathogen cell's external envelope and internal structures. The problems associated with solubility and stability of EOs had prompted the use nanotechnology such as nanoemulsions. The use of nanoemulsion to increase efficiency and supply of EOs to control plant diseases control was discussed in this present paper. The findings of this review paper may accelerate the effective use of ginger EOs in controlling tropical plant diseases.

• 산업식품공학
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• 제15권1호
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• pp.15-21
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• 2011

밤가루를 밀가루에 0%, 10%, 20%, 30% 대체한 복합분에 대하여 반죽의 물리적 특성 및 제빵 특성을 검토하고 밤가루 첨가가 빵의 기호도에 미치는 영향에 대해 조사하였다. 반죽의 물리적 특성 중 farinogram 측정 결과 밤가루의 첨가량이 증가함에 따라 반죽시간은 짧아졌으나 반죽의 안정도와 내구성이 약화되었다. Amylogram에서 호화온도는 대조군에 비해 다소 증가하는 경향을 보인반면 최고점도는 감소하였다. 반죽팽창도 측정결과 밤가루가 20%이상 첨가된 반죽은 변화가 없었으며, 제빵 후 빵의 부피가 작고 비용적도 낮았다. 밤가루 첨가에 따른 식빵의 품질평가결과 밤가루를 10% 첨가하여 제조한 식빵이 20%, 30% 첨가한 식빵에 비해 경도가 낮았으며, 내상 또한 비교적 작고 균일하였다. 밤가루 첨가시 10%이내가 좋을 것으로 사료된다.

• 대한물리의학회지
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• 제17권4호
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• pp.15-25
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• 2022

PURPOSE: This study examined the effect of bridge exercise-abdominal draw-in maneuver (ADIM) with hip adductor co-contraction on the TrA thickness and whether it is effective as a core stability exercise. METHODS: The subjects of this study, 33 men with no history in the past and who provided prior consent, were selected through interviews with male students of S University. The subjects performed five movements, including bridge exercise and ADIM, and performed two demonstrations and two exercises in advance. The abdominal muscles were measured using ultrasonography once in each movement, and the abdominal muscle tone was measured using a soft tissue tone measurement. RESULTS: There was a significant difference in the thickness between the TrA and Internal Oblique Muscles at various bridge positions (p < .05), and no significant difference with the External Oblique Muscle (p < .05). There was no significant difference in muscle tone in the Rectus abdominis part (p > .05), but a significant difference in the Oblique Muscle part (p < .05). The muscle tone of the Oblique Muscles by position showed a significant difference in Bridge, BHa, and BA compared to the rest position (p < .05), but no significant difference with BHaA (p > .05). CONCLUSION: The thickness of TrA could be increased through bridge exercise, and TrA could be activated properly using ADIM and may be an effective exercise for core stabilization.

• Molecules and Cells
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• 제41권4호
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• pp.311-319
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• 2018

The gaseous hormone ethylene influences many aspects of plant growth, development, and responses to a variety of stresses. The biosynthesis of ethylene is tightly regulated by various internal and external stimuli, and the primary target of the regulation is the enzyme 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS), which catalyzes the rate-limiting step of ethylene biosynthesis. We have previously demonstrated that the regulation of ethylene biosynthesis is a common feature of most of the phytohormones in etiolated Arabidopsis seedlings via the modulation of the protein stability of ACS. Here, we show that various phytohormones also regulate ethylene biosynthesis from etiolated rice seedlings in a similar manner to those in Arabidopsis. Cytokinin, brassinosteroids, and gibberellic acid increase ethylene biosynthesis without changing the transcript levels of neither OsACS nor ACC oxidases (OsACO), a family of enzymes catalyzing the final step of the ethylene biosynthetic pathway. Likewise, salicylic acid and abscisic acid do not alter the gene expression of OsACS, but both hormones downregulate the transcript levels of a subset of ACO genes, resulting in a decrease in ethylene biosynthesis. In addition, we show that the treatment of the phytohormones results in distinct etiolated seedling phenotypes, some of which resemble ethylene-responsive phenotypes, while others display ethylene-independent morphologies, indicating a complicated hormone crosstalk in rice. Together, our study brings a new insight into crosstalk between ethylene biosynthesis and other phytohormones, and provides evidence that rice ethylene biosynthesis could be regulated by the post-transcriptional regulation of ACS proteins.

• The Journal of Advanced Prosthodontics
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• 제6권1호
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• pp.46-52
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• 2014

PURPOSE. The aim of this study was to evaluate the interface accuracy of computer-assisted designed and manufactured (CAD/CAM) titanium abutments and implant fixture compared to gold-cast UCLA abutments. MATERIALS AND METHODS. An external connection implant system (Mark III, n=10) and an internal connection implant system (Replace Select, n=10) were used, 5 of each group were connected to milled titanium abutment and the rest were connected to the gold-cast UCLA abutments. The implant fixture and abutment were tightened to torque of 35 Ncm using a digital torque gauge, and initial detorque values were measured 10 minutes after tightening. To mimic the mastication, a cyclic loading was applied at 14 Hz for one million cycles, with the stress amplitude range being within 0 N to 100 N. After the cyclic loading, detorque values were measured again. The fixture-abutment gaps were measured under a microscope and recorded with an accuracy of ${\pm}0.1{\mu}m$ at 50 points. RESULTS. Initial detorque values of milled abutment were significantly higher than those of cast abutment (P<.05). Detorque values after one million dynamic cyclic loadings were not significantly different (P>.05). After cyclic loading, detorque values of cast abutment increased, but those of milled abutment decreased (P<.05). There was no significant difference of gap dimension between the milled abutment group and the cast abutment group after cyclic loading. CONCLUSION. In conclusion, CAD/CAM milled titanium abutment can be fabricated with sufficient accuracy to permit screw joint stability between abutment and fixture comparable to that of the traditional gold cast UCLA abutment.

• 대한물리의학회지
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• 제12권2호
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• pp.91-101
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• 2017

PURPOSE: The aim of this study was to verify the effect of trunk strengthening exercise using oscillation by comparing trunk muscle thickness, as well as balance of healthy adults during exercises performed with an oscillatory device and non-oscillatory device. METHODS: Twenty-two participants were randomly assigned to one of two groups: the trunk strengthening exercise using oscillation (TSEO) group (n=11) or the trunk strengthening exercise using non-oscillation (TSEN) group (n=11). Subjects in all groups performed the exercises three days per week for 6 weeks. All subjects performed four types of exercises: pull over, seated twist, power push, and diagonal power plank. Trunk muscle thickness of the rectus abdominis (RA), internal oblique (IO), external oblique (EO), transverse abdominis (TrA), and multifidus (MT) were measured with an ultrasonography. The balance ability were evaluated using the Romberg test with eyes open, eyes closed, one-leg standing test (OLST), and limits of stability (LOS). All tests were performed before the intervention, as well as after 6 weeks and 8 weeks of exercises. RESULTS: There was a significant difference of RA, IO, TrA, and MT according to the main effect of the time (p<.05). There was a significant difference of IO and LOS according to interaction effect between the time and group (p<.05). CONCLUSION: As intended, the cyclic forces induced by the oscillating device did increase trunk muscle thickness. However, the effect was limited and significant only for the IO muscle. Combining trunk strengthening exercise with oscillation appears to be more effective in improving dynamic balance.

• Physical Therapy Rehabilitation Science
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• 제3권2호
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• pp.101-106
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• 2014

Objective: To investigate the appropriate position for abdominal drawing-in maneuver (ADIM) exercise by rehabilitative ultrasound image. Design: Cross-sectional study. Methods: Twenty-eight young adults with no history of low back pain participated in the study. Three positions compared were crook lying position with hip $60^{\circ}$ flexion, standing position with the feet hip width apart and knees straight, and saddle standing positionunsupported with the knees $20^{\circ}$ flexed. Once in the appropriate position, the subjects were verbally cued to draw in their abdominal wall, with the intention of pulling their navel inward toward their lower back. The thickness of each transversus abdominis (TrA), internal oblique (IO), and external oblique (EO) muscles were measured via ultrasound and recorded at the end of inspiration. Results: When compared to the TrA thickness of rest, the TrA thickness was significantly increased in all three positions (crook lying, standing, and saddle standing) during the ADIM (p<0.05). IO thickness was significantly greater in standing and saddle standing than in crook lying (p<0.05). EO thickness was constant in all the three positions. Conclusions: The present study suggests that standing and saddle standing positions could be recommended for the ADIM to maximize recruitment of the TrA and IO activation. Specifically, the saddle standing position with knees flexed to $20^{\circ}$ was observed to increase the TrA activation more than the standing position. These findings should be considered when core stability exercises such as the ADIM are conducted.

• 대한정형도수물리치료학회지
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• 제29권1호
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• pp.53-67
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• 2023

Background: This study comparatively evaluated the effects of equipment-based pilates exercises (EPE) and lumbar stability exercises (LSE) in patients with chronic low back pain in terms of their Visual Analogue Scale(VAS), Oswestry Disability Index(ODI), and abdominal muscle thickness. Methods: A total of 30 participants were recruited and randomly assigned to either the EPE or the LSE. The VAS, ODI, and abdominal muscle thicknesses of the participants were measured before and after the intervention. Results: The EPE were more effective in terms of the duration of a sustained reduction in VAS scores. post hoc test revealed that EPE were more efficacious in terms of a sustained improvement in ODI scores. With respect to changes in abdominal muscle thickness, there was a significant difference in the thickness of internal oblique muscles(IO) and the external oblique muscles(EO) between the two groups. Conclusion: In this study, both types of exercise interventions resulted in improvements in the VAS, ODI scores, and abdominal muscle thickness in patients with chronic low back pain. However, EPE were found to be more effective than LPE in terms of longer sustained improvements in VAS and ODI scores. Also, with respect to abdominal muscle thickness, the thickness of EO and IO improved only in the EPE group.

• 한국지반공학회논문집
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• 제25권1호
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• pp.31-40
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• 2009

본 연구는 보강된 기존사면에 대한 새로운 사면 위험도 평가방법에 대한 연구로서 기존의 사면 안정성 및 위험도 평가방법들에서 주요 위험도 영향요소로 구분되는 강우, 암종, 배수상태 항목들에 대하여 검토하고 분석하였다. 분석 결과 사면 위험도에 영향을 미치는 19개의 주요요소를 선정하였으며 이를 Hudson(1991)이 제안한 Interaction matrix 개념의 위험도 분석 모델에 적용하였다. 적용결과 기존사면 위험도 평가방법인 SRI(Slope Risk Index)를 제시하였으며 국내 15개소 사면을 대상으로 검증을 실시하였다. 검증 결과 제시한 기존보강사면의 위험도 평가방법의 신뢰성을 확인할 수 있었다.