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Stabilized Amorphous Calcium Carbonate as a Precursor of Microcoating on Calcite

Taeyoung Jeon, Ye-Eun Na, Dongchan Jang, Il Won Kim
2020 Materials  
Second, the CaCl 2 (aq) was mixed into the premixed solution of Na 2 CO 3 (aq) and NaOH (aq) at room temperature.  ...  After curing, the sample was immersed into the mixed solution of Na 2 CO 3 (aq) and NaOH (aq), and CaCl 2 (aq) was added to start the coating formation.  ... 
doi:10.3390/ma13173762 pmid:32858839 fatcat:d4kgdrpj5ndm5jb6oj4xosz55q

3DSRnet: Video Super-resolution using 3D Convolutional Neural Networks [article]

Soo Ye Kim, Jeongyeon Lim, Taeyoung Na, Munchurl Kim
2019 arXiv   pre-print
In video super-resolution, the spatio-temporal coherence between, and among the frames must be exploited appropriately for accurate prediction of the high resolution frames. Although 2D convolutional neural networks (CNNs) are powerful in modelling images, 3D-CNNs are more suitable for spatio-temporal feature extraction as they can preserve temporal information. To this end, we propose an effective 3D-CNN for video super-resolution, called the 3DSRnet that does not require motion alignment as
more » ... eprocessing. Our 3DSRnet maintains the temporal depth of spatio-temporal feature maps to maximally capture the temporally nonlinear characteristics between low and high resolution frames, and adopts residual learning in conjunction with the sub-pixel outputs. It outperforms the most state-of-the-art method with average 0.45 and 0.36 dB higher in PSNR for scales 3 and 4, respectively, in the Vidset4 benchmark. Our 3DSRnet first deals with the performance drop due to scene change, which is important in practice but has not been previously considered.
arXiv:1812.09079v2 fatcat:ud4j5vsuqfgxbjodkhuvbu32xe

Robot-assisted anastomosis of an incidentally transected right gastroepiploic artery

Taeyoung Yun, Kwon Joong Na, Chang Hyun Kang
2020 Interactive Cardiovascular and Thoracic Surgery  
Interactive CardioVascular and Thoracic Surgery thanks Clemens Aigner and Paolo Strignano for their contribution to the peer review process of this article. Video 1: Robot-assisted minimally invasive oesophagectomy gains its popularity as it results in less postoperative complications and better quality of life than open surgery. Though robotic surgery has enabled complex surgical procedures, microvascular procedures such as repairing the injured artery during robotic surgery remain a
more » ... Here, we present a successful end-to-end anastomosis of incidentally transected right gastroepiploic artery during robot-assisted minimally invasive oesophagectomy for a 78-year-old man with advanced oesophageal cancer.
doi:10.1093/icvts/ivaa122 pmid:32766695 fatcat:n4jtht5nhnfnraneh5qtuz5tqm

Activated Biomass-derived Graphene-based Carbons for Supercapacitors with High Energy and Power Density

SungHoon Jung, Yusik Myung, Bit Na Kim, In Gyoo Kim, In-Kyu You, TaeYoung Kim
2018 Scientific Reports  
Here, we present a facile and low-cost method to produce hierarchically porous graphene-based carbons from a biomass source. Three-dimensional (3D) graphene-based carbons were produced through continuous sequential steps such as the formation and transformation of glucose-based polymers into 3D foam-like structures and their subsequent carbonization to form the corresponding macroporous carbons with thin graphene-based carbon walls of macropores and intersectional carbon skeletons. Physical and
more » ... chemical activation was then performed on this carbon to create micro-and meso-pores, thereby producing hierarchically porous biomass-derived graphene-based carbons with a high Brunauer-Emmett-Teller specific surface area of 3,657 m 2 g −1 . Owing to its exceptionally high surface area, interconnected hierarchical pore networks, and a high degree of graphitization, this carbon exhibited a high specific capacitance of 175 F g −1 in ionic liquid electrolyte. A supercapacitor constructed with this carbon yielded a maximum energy density of 74 Wh kg −1 and a maximum power density of 408 kW kg −1 , based on the total mass of electrodes, which is comparable to those of the state-of-the-art graphene-based carbons. This approach holds promise for the low-cost and readily scalable production of high performance electrode materials for supercapacitors. Supercapacitors or electric double layer capacitors store charges by adsorption and desorption of electrolyte ions at electrodes, as opposed to batteries which rely on electrochemical redox reactions 1-5 . This allowed supercapacitors to attain a high power density that is an order of magnitude larger than that of lithium ion batteries. Hence, supercapacitors find use in high power applications such as electronic devices and electric vehicles 2,6-8 . However, the low energy density of supercapacitors as compared to batteries hampers their widespread application. Therefore, it is imperative to develop supercapacitors with high power and energy density 4,9 . To improve the capacitance and energy density of supercapacitors, it is essential to develop carbon-based electrode materials with high specific surface area (SSA) that is easily accessible to electrolyte ions 10 . Although the commercial activated carbons (AC) are the most widely used electrode materials for supercapacitors, they suffer from low capacitance resulting from their pore architecture which may hinder ion transportation and access into the pores 11 . In this regard, graphene is a potential material for supercapacitor electrodes because of its unique two-dimensional (2D) structure, high theoretical SSA, and high electrical conductivity 12 . Although the energy and power density of supercapacitors has been significantly improved by the use of graphene-based electrodes, their specific capacitance is still lower than the theoretical value 13 . Another reason for the limitation of the widespread use of graphene-based supercapacitor electrodes is their high cost owing to the long production time and multiple processing steps (e.g. oxidation of graphite into graphite oxide, exfoliation of graphite oxide into graphene oxide, reduction of graphene oxide, separation, and washing) involved in their fabrication 14 . Therefore, the development of well-designed, low-cost carbon-based materials with large accessible surface area and controllable porosity is essential for improving the performance of supercapacitors. In this context, hierarchically porous graphene-based carbons composed of thin walls of graphitic carbons and three-dimensionally interconnected pores on various length scales are considered to be promising electrode materials, since they offer the advantages of both graphene-based materials and activated carbons. While thin walls of graphitic carbons Published: xx xx xxxx OPEN 2 Scientific REPORTS | (2018) 8:1915 |
doi:10.1038/s41598-018-20096-8 pmid:29382861 pmcid:PMC5789836 fatcat:cn3ru3w6rjhtlpsvedmmz7wnji

A RNA producing DNA hydrogel as a platform for a high performance RNA interference system

Jaejung Song, Minhyuk Lee, Taeyoung Kim, Jeongkyeong Na, Yebin Jung, Gyoo Yeol Jung, Sungjee Kim, Nokyoung Park
2018 Nature Communications  
D NA has been mainly considered as a genetic material in biological systems, but there have been recent tremendous efforts to use these nucleic acids for various generic applications, such as building  ... 
doi:10.1038/s41467-018-06864-0 pmid:30337586 pmcid:PMC6193956 fatcat:oxchg3xmbrcapehnovism64nk4

An ROI/xROI Based Rate Control Algorithm in H.264|AVC for Video Telephony Applications [chapter]

Changhee Kim, Taeyoung Na, Jeongyeon Lim, Youngho Joo, Kimun Kim, Jaewoan Byun, Munchurl Kim
2009 Lecture Notes in Computer Science  
Channel bandwidth in 3G communication networks is very much limited for video telephony services. Therefore, it is worthwhile to enhance a subjective quality of video contents via ROI based coding. In this paper, An ROI/xROI based rate-control method is proposed, which considers the coding of both the ROI and the extended ROIs (xROI's) in non-ROI to meet given target bitrates. In the proposed method, the QP values are increasingly assigned in MB wide inside the non-ROI away from ROI. This
more » ... s the abrupt change in visual quality and the amounts of residual signals along the border between ROI and non-ROI. In this regard, the subjective visual quality is enhanced as well as the proposed rate control has flexibility to control the amounts of the output bitstreams. Experimental results show that the proposed scheme can more effectively achieve the average target bitrates with the better subjective quality than the existing rate control algorithm in H.264|AVC by reducing the variation of the output bitstream amounts.
doi:10.1007/978-3-540-92957-4_88 fatcat:pjhxpuxiojfuhn2nui4tfrd75e

Digital rectal examination in a simulated environment using sweeping palpation and mechanical localization

Yeongjin Kim, Bummo Ahn, Youngjin Na, Taeyoung Shin, Koonho Rha, Jung Kim
2014 International Journal of Precision Engineering and Manufacturing  
Computerized palpation systems have been studied for the quantitative characterization of prostate properties. The aim of this study was to evaluate the reliability of mechanical tumor localization maps by estimating correlation with pathological maps. A total of 120 indentations were performed on 10 specimens by using a sweeping palpation system in simulated environment conditions. Suspicious tumor lesions from the mechanical localization were compared to those of the pathological maps. The
more » ... cordance rate between the mechanical localization maps and pathological maps was 81.7% (98/120). The positive predictive value (PPV) and the negative predictive value (NPV) of the proposed localization system were 78.6% (59/75) and 86.7% (39/45), respectively. Based on these data, the suspicious tumor lesions of mechanical localization maps were in close agreement with those from the pathological maps. The findings suggest that the high compatibility and detection rate of prostate tumor could be enhanced if computerized palpation and the conventional diagnosis are used synergistically. This study may contribute to technological progress in overcoming diagnostic limitations, which include many complications from digital rectal examination (DRE) and transrectal ultrasound (TRUS) guided needle biopsy.
doi:10.1007/s12541-013-0321-6 fatcat:vfmpz77s5nacfjwqrhacn5ibzy

Machine learning prediction of stone-free success in patients with urinary stone after treatment of shock wave lithotripsy

Seung Woo Yang, Yun Kyong Hyon, Hyun Seok Na, Long Jin, Jae Geun Lee, Jong Mok Park, Ji Yong Lee, Ju Hyun Shin, Jae Sung Lim, Yong Gil Na, Kiwan Jeon, Taeyoung Ha (+2 others)
2020 BMC Urology  
The aims of this study were to determine the predictive value of decision support analysis for the shock wave lithotripsy (SWL) success rate and to analyze the data obtained from patients who underwent SWL to assess the factors influencing the outcome by using machine learning methods. We retrospectively reviewed the medical records of 358 patients who underwent SWL for urinary stone (kidney and upper-ureter stone) between 2015 and 2018 and evaluated the possible prognostic features, including
more » ... atient population characteristics, urinary stone characteristics on a non-contrast, computed tomographic image. We performed 80% training set and 20% test set for the predictions of success and mainly used decision tree-based machine learning algorithms, such as random forest (RF), extreme gradient boosting trees (XGBoost), and light gradient boosting method (LightGBM). In machine learning analysis, the prediction accuracies for stone-free were 86.0, 87.5, and 87.9%, and those for one-session success were 78.0, 77.4, and 77.0% using RF, XGBoost, and LightGBM, respectively. In predictions for stone-free, LightGBM yielded the best accuracy and RF yielded the best one in those for one-session success among those methods. The sensitivity and specificity values for machine learning analytics are (0.74 to 0.78 and 0.92 to 0.93) for stone-free and (0.79 to 0.81 and 0.74 to 0.75) for one-session success, respectively. The area under curve (AUC) values for machine learning analytics are (0.84 to 0.85) for stone-free and (0.77 to 0.78) for one-session success and their 95% confidence intervals (CIs) are (0.730 to 0.933) and (0.673 to 0.866) in average of methods, respectively. We applied a selected machine learning analysis to predict the result after treatment of SWL for urinary stone. About 88% accurate machine learning based predictive model was evaluated. The importance of machine learning algorithm can give matched insights to domain knowledge on effective and influential factors for SWL success outcomes.
doi:10.1186/s12894-020-00662-x pmid:32620102 fatcat:zxenuk2kszf2vfobacor6gi5sq

Mechanically inferior constituents in spider silk result in mechanically superior fibres by adaptation to harsh hydration conditions: a molecular dynamics study

Yoonjung Kim, Myeongsang Lee, Inchul Baek, Taeyoung Yoon, Sungsoo Na
2018 Journal of the Royal Society Interface  
Spider silk exhibits mechanical properties such as high strength and toughness that are superior to those of any man-made fibre (Bourzac 2015 Nature 519, S4 -S6 (doi:10.1038/519S4a)). This high strength and toughness originates from a combination of the crystalline (exhibiting robust strength) and amorphous (exhibiting superb extensibility) regions present in the silk (Asakura et al. 2015 Macromolecules 48, 2345-2357.1021/acs. macromol.5b00160)). The crystalline regions comprise a mixture of
more » ... yalanine and poly-glycine-alanine. Poly-alanine is expected to be stronger than poly-glycine-alanine, because alanine exhibits greater interactions between the strands than glycine (Tokareva et al. )). We connect this characteristic sequence to the interactions observed upon the hydration of spider silk. Like most proteinaceous materials, spider silks become highly brittle upon dehydration, and thus water collection is crucial to maintaining its toughness (Gosline et al. 1986 Endeavour 10, 37-43 (doi:10.1016/0160-9327(86)90049-9)). We report on the molecular dynamic simulations of spider silk structures with different sequences for the crystalline region of the silk structures, of wild-type (WT), poly-alanine, and poly-glycine-alanine. We reveal that the characteristic sequence of spider silk results in the b-sheets being maintained as the degree of hydration changes and that the high water collection capabilities of WT spider silk sequence prevent the silk from becoming brittle and weak in dry conditions. The characteristic crystalline sequence of spider dragline silk is therefore relevant not for maximizing the interactions between the strands but for adaption to changing hydration conditions to maintain an optimal performance even in harsh conditions.
doi:10.1098/rsif.2018.0305 pmid:30021926 fatcat:5n5gxsgwlnd53fbtutb3heb6gq

The First Generation of iPSC Line from a Korean Alzheimer's Disease Patient Carrying APP-V715M Mutation Exhibits a Distinct Mitochondrial Dysfunction

Ling Li, Jee Hoon Roh, Hee Jin Kim, Hyun Jung Park, Minchul Kim, Wonyoung Koh, Hyohoon Heo, Jong Wook Chang, Mahito Nakanishi, Taeyoung Yoon, Duk L. Na, Jihwan Song
2019 Experimental Neurobiology  
Alzheimer's Disease (AD) is a progressive neurodegenerative disease, which is pathologically defined by the accumulation of amyloid plaques and hyper-phosphorylated tau aggregates in the brain. Mitochondrial dysfunction is also a prominent feature in AD, and the extracellular Aβ and phosphorylated tau result in the impaired mitochondrial dynamics. In this study, we generated an induced pluripotent stem cell (iPSC) line from an AD patient with amyloid precursor protein (APP) mutation (Val715Met;
more » ... APP-V715M) for the first time. We demonstrated that both extracellular and intracellular levels of Aβ were dramatically increased in the APP-V715M iPSC-derived neurons. Furthermore, the APP-V715M iPSC-derived neurons exhibited high expression levels of phosphorylated tau (AT8), which was also detected in the soma and neurites by immunocytochemistry. We next investigated mitochondrial dynamics in the iPSC-derived neurons using Mito-tracker, which showed a significant decrease of anterograde and retrograde velocity in the APP-V715M iPSC-derived neurons. We also found that as the Aβ and tau pathology accumulates, fusion-related protein Mfn1 was decreased, whereas fission-related protein DRP1 was increased in the APP-V715M iPSC-derived neurons, compared with the control group. Taken together, we established the first iPSC line derived from an AD patient carrying APP-V715M mutation and showed that this iPSC-derived neurons exhibited typical AD pathological features, including a distinct mitochondrial dysfunction.
doi:10.5607/en.2019.28.3.329 pmid:31308793 pmcid:PMC6614069 fatcat:wllmhzdcgvem3mjl5josg6a4je

Genome sequence of mungbean and insights into evolution within Vigna species

Yang Jae Kang, Sue K. Kim, Moon Young Kim, Puji Lestari, Kil Hyun Kim, Bo-Keun Ha, Tae Hwan Jun, Won Joo Hwang, Taeyoung Lee, Jayern Lee, Sangrea Shim, Min Young Yoon (+18 others)
2014 Nature Communications  
Mungbean (Vigna radiata) is a fast-growing, warm-season legume crop that is primarily cultivated in developing countries of Asia. Here we construct a draft genome sequence of mungbean to facilitate genome research into the subgenus Ceratotropis, which includes several important dietary legumes in Asia, and to enable a better understanding of the evolution of leguminous species. Based on the de novo assembly of additional wild mungbean species, the divergence of what was eventually domesticated
more » ... nd the sampled wild mungbean species appears to have predated domestication. Moreover, the de novo assembly of a tetraploid Vigna species (V. reflexo-pilosa var. glabra) provides genomic evidence of a recent allopolyploid event. The species tree is constructed using de novo RNA-seq assemblies of 22 accessions of 18 Vigna species and protein sets of Glycine max. The present assembly of V. radiata var. radiata will facilitate genome research and accelerate molecular breeding of the subgenus Ceratotropis.
doi:10.1038/ncomms6443 pmid:25384727 pmcid:PMC4241982 fatcat:brkuny53nnek3neb5k7tdud6oa

Distinct mechanisms for the upconversion of NaYF4:Yb3+,Er3+ nanoparticles revealed by stimulated emission depletion

Kyujin Shin, Taeyoung Jung, Eunsang Lee, Gibok Lee, Yeongchang Goh, Junseok Heo, Minhyuk Jung, Eun-Jung Jo, Hohjai Lee, Min-Gon Kim, Kang Taek Lee
2017 Physical Chemistry, Chemical Physics - PCCP  
This beam was focused on a specimen by the objective lens (PlanC N 10X/0.25 NA lens, Olympus). Two laser beams were switched on and off by shutters (SC10, Thorlabs).  ...  Technology), and a spectrometer (QE65000, Ocean Optics). 980-nm laser beam was reflected by the dichroic mirror (ZT775sp-2p-UF1, Chroma) and focused on UCNP samples by the objective lens (Apo N 60X/1.49 NA  ... 
doi:10.1039/c7cp00918f pmid:28367577 fatcat:gxhvjnultfa7hjm2rcxkb7iz3u

Filter for TV and video cameras

L. I. Berezhinsky, Institute of Semiconductor Physics, NAS of Ukraine, 45, prospect Nauky, 03028 Kyiv, Ukraine Phone: +38 (044) 525-5778. E-mail:
2005 Semiconductor Physics, Quantum Electronics & Optoelectronics  
Fig. 3 . 3 Optical characteristics of IR-cut filters, produced by Melles Griot (USA) (1) and Taeyoung (Korea) (2) . The design and layer thicknesses of the IR cut-filter.  ...  For comparison, the transmittance of available commercial filters comprising 29 to 30 layers and manufactured by Taeyoung (Korea) and Melles Griot (USA), which are used in modern TV and video cameras,  ... 
doi:10.15407/spqeo8.01.106 fatcat:znumd3nplffzjdefufx5lk3abe

Page 8060 of Mathematical Reviews Vol. , Issue 2003j [page]

2003 Mathematical Reviews  
Honecker, Gabriele Hong, Chan Yong Hong, Sung Sa Hong, Yoon Hi Hongo, Kohei Honkala, liro RC I os ctiodacie na csacisanenecee a Horbachuk, O. L. .. See Gorbachuk, O. L.  ...  Ha, Taeyoung Haake, Claus-Jochen Haake, Fritz . Haas, Shane M. Haas, Wolfgang Fee Habsieger, Laurent Hackett-Jones, Emily J. Haddad, L. ........... See Haddad, Lucien Haddad, Lucien Hadeler, K.  ... 

Electrical Impedance Detection of Senescence in Adipose Tissue-derived Stem Cells

Hee-Sook Jun, Lan Thi Mai Dao, Sungbo Cho
2012 Procedia Engineering  
Methodology Fabrication of ITO Electrode-based Chip Glass slides coated by ITO and with a sheet resistance of 4 /sq were purchased (Taeyoung Optics, Incheon, Korea).  ...  The amplitude of the input current was restricted to 100 nA by serially connecting a 100 k resistor to the internal function generator of the lock-in-amplifier, which resulted in the maximum current density  ... 
doi:10.1016/j.proeng.2012.09.323 fatcat:vpdzrmzqebbklkj4e36zfakotm
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