• 한국세라믹학회지
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• 제56권1호
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• pp.71-76
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• 2019

Monochromatic amber phosphor in glasses (PiGs) for automotive LED applications were fabricated with $YAG:Ce^{3+}$, $CaAlSiN_3:Eu^{2+}$ phosphors and Pb-free silicate glass. After synthesis and thickness-thinning process, PiGs were mounted on high-power blue LED to make monochromatic amber LEDs. PiGs were simple mixtures of 566 nm yellow YAG, 615 nm red $CaAlSiN_3:Eu^{2+}$ phosphor and transparent glass frit. The powders were uniaxially pressed and treated again through CIP (cold isostatic pressing) at 200 MPa for 20 min to increase packing density. After conventional thermal treatment at $550^{\circ}C$ for 30 min, PiGs were applied by using GPS (gas pressure sintering) to obtain a fully dense PiG plate. As the phosphor content increased, the density of the sintered body decreased and PiGs containing 30 wt% phosphor had full sintered density. Changes in photoluminescence spectra and color coordination were investigated by varying the ratio of $YAG/CaAlSiN_3$ and the thickness of the plates. Considering the optical spectrum and color coordinates, PiG plates with $240{\mu}m$ thickness showed a color purity of 98% and a wavelength of about 605 nm. Plates exhibit suitable optical characteristics as amber light-converting material for automotive LED applications.

• 한국광학회지
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• 제25권2호
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• pp.102-107
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• 2014

본 논문에서는 현재 양산되고 있는 Red(621 nm), Green(530 nm), Blue(453 nm), Amber(590 nm) 등 4파장의 LED 조합을 이용하여 색온도가 가변되는 동안에도 평균연색지수 및 특별연색지수 R9 값이 높게 유지될 수 있도록 조명의 스펙트럼을 최적화하였다. 최적화 시 설계의 정확도를 높이기 위하여 실제 측정한 LED 스펙트럼을 사용하였고 광선과 기구물 사이의 상호 작용을 고려한 광선 추적 기법을 활용하여 수행하였다 또한 최적화 결과를 검증하기 위하여 색온도 가변 조명 장치를 직접 제작하였으며 광 특성을 평가한 결과 색온도가 3000 K에서 6000 K까지 변하는 동안 CRI 및 R9 값이 각각 87~90, 34~93을 나타내었다.

• 반도체디스플레이기술학회지
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• 제3권4호
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• pp.39-43
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• 2004

The parallel multi-quantum well structures of blue and amber lights were designed and grown in metal-organic chemical vapor deposition by utilizing integration process on epitaxial layers. Samples were deposited for 5 periods-InGaN multi-quantum well layers for blue light emission and partially etched in order to regrow the 3 periods-InGaN multi-quantum wells for amber light. The blue and amber photoluminescence spectra were observed at the peak wavelengths of 475 and 580 nm, respectively. The chromatic coordinates of the white emitting diode were 0.31 and 0.34.

• 조명전기설비학회논문지
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• 제27권9호
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• pp.15-22
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• 2013

A new LED lamp driving technology with a charge pump instead of a conventional DC-DC converter is proposed. The proposed driving technology is used to control the LED lamp with digital dimming. The power loss in the zener diodes is reduced because the charging process of the capacitors is selectively controlled according to the digital control signal. From the experimental results, when dimming four LED lamps simultaneously, the average driving circuit efficiency of 89% is obtained, regardless of the dimming level. White light with color temperature over a range of 2800~7200K was produced by dimming control of red, green, blue and amber LED lamps with the proposed driving circuit. The characteristics of the driving circuits can be changed depending on the characteristics of the R, G, B, and A LED lamps. The efficiency of the driving circuits up to a maximum 89% can also be obtained depending on the combination of LED lamps. The driving technology with digital dimming control for LED lamps proposed in this paper would be effective for obtaining high efficiency in LED driving circuits and remote control of LED lamps using digital communications.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1713-1719
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• 2014

1FSD is a 28-residue designed protein with a ${\beta}{\beta}{\alpha}$ motif. Since this protein displays most essential features of protein structures in such a small size, this model protein can be an outstanding system for evaluating the balance in the propensity of the secondary structures and the quality of all-atom protein force fields. Particularly, this protein would be difficult to fold to its correct native structure without establishing proper balances between the secondary structure elements in all-atom energy functions. In this work, a series of the recently optimized five amber protein force fields [$ff03^*$, $f99sb^*$-ildn, ff99sb-${\phi}^{\prime}$-ildn, ff99sb-nmr1-ildn, ff99sb-${\Phi}{\Psi}$(G24, CS)-ildn] were investigated for the simulations of 1FSD using a conventional molecular dynamics (MD) and a biased-exchange meta-dynamics (BEMD) methods. Among those tested force fields, we found that ff99sb-nmr1-ildn and ff99sb-${\Phi}{\Psi}$(G24, CS)-ildn are promising in that both force fields can locate the native state of 1FSD with a high accuracy (backbone rmsd ${\leq}1.7{\AA}$) in the global free energy minimum basin with a reasonable energetics conforming to a previous circular dichroism (CD) experiment. Furthermore, both force fields led to a common set of two distinct folding pathways with a heterogeneous nature of the transition state to the folding. We anticipate that these force fields are reasonably well balanced, thereby transferable to many other protein folds.

• Journal of Korean Neurosurgical Society
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• 제55권5호
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• pp.277-279
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• 2014

Autonomic dysreflexia is a clinical emergency syndrome of uncontrolled sympathetic output that can occur in patients who have a history of spinal cord injury. Despite its frequency in spinal cord injury patients, central nervous system complications are very rare. We report a man with traumatic high level incomplete spinal cord injury who suffered hypertensive right thalamic hemorrhage secondary to an episode of autonomic dysreflexia. Prompt recognition and removal of the triggering factor, the suprapubic catheter obstruction which led to hypertensive attack, the patient had a favorable functional outcome after the resorption of the hematoma and effective rehabilitation programme.

• 한국환경과학회지
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• 제22권11호
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• pp.1499-1508
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• 2013

In the results of investigating the role of LED light quality in enhancing the ornamental value of indoor foliage plants, amber and red light increased plant height, leaf width, and leaf stalk, and the consequent tree shape decreased the ornamental value. The chlorophyll content increased significantly under white light and compound light. With regard to the effect of plant leaf color on ornamental value, the value of lightness was markedly enhanced by red light. As to the functionality of plants according to photosynthetic activity, plants such as Dieffenbachia, Clusia, and Dracaena were found favorable to those staying indoors for a longtime from morning to evening. Spathiphyllum, and Ficus were found to be recommendable for indoor spaces used actively during afternoon because their photosynthesis was activated in the afternoon. With regard to power consumption according to light quality, white light consumed 119 W/hour, around 45% lower than that of fluorescent lamps, so it is considered the optimal artificial light quality that can enhance energy efficiency. Red light consumed 72 W/hour, only 33% of that of fluorescent lamps, but it was not considered the optimal light quality because plant growth was poor under the light quality. White light and compound light were found to be the ideal light sources for improving the functionality and ornamental value of indoor plants and reducing the cost of maintenance, but because compound light hinders people from recognizing the original color of plants and makes their eyes easily tired, white light was considered the optimal light satisfying all of the ornamental value, economic efficiency and functionality resulting from plant growth.

• Journal of Microbiology and Biotechnology
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• 제30권10호
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• pp.1583-1591
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• 2020

CRISPR/Cpf1 has emerged as a new CRISPR-based genome editing tool because, in comparison with CRIPSR/Cas9, it has a different T-rich PAM sequence to expand the target DNA sequence. Single-base editing in the microbial genome can be facilitated by oligonucleotide-directed mutagenesis (ODM) followed by negative selection with the CRISPR/Cpf1 system. However, single point mutations aided by Cpf1 negative selection have been rarely reported in Corynebacterium glutamicum. This study aimed to introduce an amber stop codon in crtEb encoding lycopene hydratase, through ODM and Cpf1-mediated negative selection; deficiency of this enzyme causes pink coloration due to lycopene accumulation in C. glutamicum. Consequently, on using double-, triple-, and quadruple-base-mutagenic oligonucleotides, 91.5-95.3% pink cells were obtained among the total live C. glutamicum cells. However, among the negatively selected live cells, 0.6% pink cells were obtained using single-base-mutagenic oligonucleotides, indicating that very few single-base mutations were introduced, possibly owing to mismatch tolerance. This led to the consideration of various target-mismatched crRNAs to prevent the death of single-base-edited cells. Consequently, we obtained 99.7% pink colonies after CRISPR/Cpf1-mediated negative selection using an appropriate single-mismatched crRNA. Furthermore, Sanger sequencing revealed that single-base mutations were successfully edited in the 99.7% of pink cells, while only two of nine among 0.6% of pink cells were correctly edited. The results indicate that the target-mismatched Cpf1 negative selection can assist in efficient and accurate single-base genome editing methods in C. glutamicum.

• Archives of Plastic Surgery
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• 제45권4호
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• pp.345-350
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• 2018

Background The radial forearm free flap (RFFF) has remained a leading choice of many plastic surgeons as a fasciocutaneous flap due to its versatility, pedicle length, and simple elevation technique. However, donor site morbidity has led many reconstructive surgeons to limit their use of the RFFF and to use other flaps instead. We propose that using a narrow RFFF (nRFFF) decreases the aesthetic and functional morbidity of the donor site. Methods We report our experiences with the nRFFF from April 2012 through May 2015 at the Department of Plastic, Reconstructive, and Hand Surgery at Liaquat National Hospital, Karachi. The donor defects were closed primarily. The Stony Brook Scar Evaluation Scale and comparison with the contralateral hand were used to assess aesthetic and functional outcomes, respectively. Results A total of 24 patients underwent nRFFF procedures during the study period. The donor arm showed excellent motor function in 22 cases (91.7%), and very good function in the remaining two cases (8.3%). The aesthetic outcomes were excellent in four patients (16.6%), very good in eight patients (33.3%), good in 10 patients (41.6%), and fair in two patients (8.3%) who developed a hypertrophic scar. All flaps were successful and there were no cases of partial or complete loss. Conclusions For small to medium-sized soft tissue defects, the nRFFF had acceptable outcomes due to its thinness, pliability, and major reduction in donor site aesthetic and functional morbidity.