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Effects of Reduced Sediment Dynamics on Fluvial Channel Geomorphology in the Jiseok River
유사계의 역동성 감소가 지석천 충적하도의 지형변화에 미치는 영향

Gi-Young Ock, Sam-Hee Lee
2012 Journal of Korea Water Resources Association  
Study Sites is Located at Mid of Jiseok 댐하류의 조절하천과 유사한 지형적 변화를 보이는 경 우를 흔히 발견하게 된다.  ...  Correspond to Those of Official Reports in the Jiseok River 0% 20% 40% 60% 80% 100% 0 1 10 100 1000 Grain size(mm) Percent finer S1 S2 S3 S4 S5 Fig. 7.  ... 
doi:10.3741/jkwra.2012.45.5.445 fatcat:36wpvotzcrf7tooexmnk5qbbfm

Excitation/Inhibition Imbalance in Animal Models of Autism Spectrum Disorders

Eunee Lee, Jiseok Lee, Eunjoon Kim
2017 Biological Psychiatry  
Imbalances between excitation and inhibition in synaptic transmission and neural circuits have been implicated in autism spectrum disorders. Excitation and inhibition imbalances are frequently observed in animal models of autism spectrum disorders, and their correction normalizes key autistic-like phenotypes in these animals. These results suggest that excitation and inhibition imbalances may contribute to the development and maintenance of autism spectrum disorders and represent an important therapeutic target.
doi:10.1016/j.biopsych.2016.05.011 pmid:27450033 fatcat:yryciucp7bfl3hf6aerulfcpfu

Hydrogel-based colorimetric assay for multiplexed microRNA detection in a microfluidic device

Hyewon Lee, Jiseok Lee, Seung-Goo Lee, Patrick S Doyle
2020 Analytical Chemistry  
Analytical Chemistry pubs.acs.org/ac Article Massachusetts 02139, The United States; orcid.org/0000-0003-2147-9172; Email: pdoyle@mit.edu Seung-Goo Lee − Synthetic Biology and Bioengineering Research Center  ... 
doi:10.1021/acs.analchem.9b05043 pmid:32207967 pmcid:PMC7178251 fatcat:her5cmh3ajbabhw36k4kclbqaa

Flow around a flexible plate in a free stream

Lee JiSeok, Lee SangHwan
2011 Journal of Mechanical Science and Technology  
Lee and Lee [11] improved the accuracy without additional neighbor lattice information using the adaptive relaxation time.  ... 
doi:10.1007/s12206-010-1212-8 fatcat:ktrnzkcwdrd7rg57reseyio7se

The Prospects of UNFCCC and Negotiation Scenario Study

Jiseok Lee
2008 Journal of Social Science  
본 연구의 구성은 제2장에서 기후변화협약의 논의동향과 교토의정서에 대해 살펴보고, 제3장에서 교토의정서 이 지 석 (Jiseok Lee) 세명대학교 국제통상학과, 조교수 jiseok@semyung.ac.kr 요 약 106❙사회과학연구 제34권 제3호 Ⅰ. 서 론  ... 
doi:10.15820/khjss.2008.34.3.005 fatcat:ws5tgyemjbandnp4t4y3u647um

Contaminated facade identification using convolutional neural network and image processing

Jiseok Lee, Jooyoung Hong, Garam Park, Hwa Soo Kim, Sungon Lee, TaeWon Seo
2020 IEEE Access  
doi:10.1109/access.2020.3027839 fatcat:ahaze3rmzvhv3id6ujvdplhztm

High-Throughput Contact Flow Lithography

Gaelle C. Le Goff, Jiseok Lee, Ankur Gupta, William Adam Hill, Patrick S. Doyle
2015 Advanced Science  
Le Goff , Jiseok Lee , Ankur Gupta , William Adam Hill ,* and Patrick S. Doyle * DOI: 10.1002/advs.201500149 the material in the mold.  ... 
doi:10.1002/advs.201500149 pmid:27980910 pmcid:PMC5115321 fatcat:4l5sfigvdzgajnpc5uhh3o3zii

Polydiacetylene-Liposome Microarrays for Selective and Sensitive Mercury(II) Detection

Jiseok Lee, Hayeon Jun, Jinsang Kim
2009 Advanced Materials  
By Jiseok Lee, Hayeon Jun, and Jinsang Kim* Conjugated polymers (CPs) are emerging materials for many useful applications.  ... 
doi:10.1002/adma.200900639 fatcat:5h5njftiwvejtho5uc4xzhybre

Stop flow lithography in perfluoropolyether (PFPE) microfluidic channels

Ki Wan Bong, Jiseok Lee, Patrick S. Doyle
2014 Lab on a Chip  
doi:10.1039/c4lc00877d pmid:25316504 fatcat:5j42p2daqjdendoronroaz3mxq

Highly Emissive Self-assembled Organic Nanoparticles having Dual Color Capacity for Targeted Immunofluorescence Labeling

Hyong-Jun Kim, Jiseok Lee, Tae-Hoon Kim, Taek Seung Lee, Jinsang Kim
2008 Advanced Materials  
Immunofluorescence labeling is a very important analytical technique for probing the structure of living cells. Such labeling is conventionally carried out by using fluorescent organic dyes. However, some drawbacks including a limited range of light emission and particularly poor photo-stability [1] have limited the usage of organic dyes. After the introduction of semiconducting quantum dots [2, 3] many research groups have investigated inorganic quantum dots [4] for immunofluorescence labeling
more » ... due to their high quantum yield, [5] high molar extinction coefficients, broad absorption with narrow light emission, and good photo physical and chemical stability. [6] [7] [8] [9] Despite the promising properties of semiconducting quantum dots for immunofluorescence labeling, cyto-toxicity is a critical problem in any live-cell or animal experiments. [10, 11] Alternative choices are dye-loaded latex particles and dye-doped silica colloids having improved photostability compared to conventional dye molecules. However, dye-loaded beads also have a critical limit of brightness due to self-quenching when high density of dyes present at the nanoparticle surface. In this context, developing highly emissive, biocompatible, and chemically readily modifiable luminescent materials is strongly desired. Recently, a few papers have been published reporting conjugated organic small molecules that showed higher quantum yield in the solid state than in solution. [12] [13] [14] [15] [16] In other words, self-quenching does not exist in these unique molecules. It has opened a new possibility to develop non-toxic organic nanoparticles with enhanced emission for various applications including immunofluorescence labeling. The reason for the lower quantum yield in solution of some of these molecules is believed that the conjugated backbone of the molecules is significantly twisted by steric hindrance [13] and the radiative decay pathway of the resulting twisted chromophores [17] is generally suppressive. Therefore, planarization of the twisted conjugated backbone upon aggregation in the solid state accordingly enhances the emissive property of the molecules. On the other hand, another class of molecules that has a larger quantum yield in the solid state has a different reason for the enhanced emissive property. These molecules in solution have a low quantum yield because they dissipate energy for molecular rotation. Therefore, they have even 20% higher quantum yield in the solid state because the molecular rotation is hindered by adjacent molecules in the solid state. [12] [13] [14] [15] [16] [17] We have developed highly emissive organic nanoparticles by using colloidal self-assembly of a hydroxyphenyl-benzoxazole (HBO) derivative and diacetylene monomers. Various heterocyclic molecules including HBO have been investigated by many research groups due to their chemical and thermal stability as well as their high electron mobility. HBO has a high extinction coefficient and excellent stability in the UV range and has shown potential as a UV stabilizer. HBO is also known to undergo excited state intramolecular proton transfer (ESIPT) upon photo-excitation as illustrated in Figure 1A . We synthesized 1,4-di(3-(benzoxazol-2-yl)-4-hydroxyphenyl)-2,5-dihexyloxybenzene (DBO) as shown in Figure 1B . The absorption and photoluminescence spectra of DBO are shown in Figure 2C . Dilute solution of DBO in tetrahydrofuran (THF) has absorption l max at 335 nm assigned to syn-enol and emits at 518 nm, showing a large Stokes shift due to ESIPT. A nanoparticle dispersion of DBO was prepared by adding THF solution of DBO to water to induce aggregate formation. The prepared nanoparticles in the mixed solution of THF: H 2 O (1:9 v/v) show a broad aggregation band above 400 nm due to Mie scattering (Fig. 2C ). [18] Interestingly their fluorescence quantum yield (F F ) was 10%, which is more than 3 times larger than the quantum yield of the THF solution (3%). The enhanced fluorescence emission intensity in the aggregates is believed to originate from a more planar structure induced by J-type aggregation through
doi:10.1002/adma.200701601 fatcat:upspenpfz5gx3f4dcdz2l3qzh4

Site-specific monoubiquitination downregulates Rab5 by disrupting effector binding and guanine nucleotide conversion

Donghyuk Shin, Wooju Na, Ji-Hyung Lee, Gyuhee Kim, Jiseok Baek, Seok Hee Park, Cheol Yong Choi, Sangho Lee
2017 eLife  
Rab GTPases, which are involved in intracellular trafficking pathways, have recently been reported to be ubiquitinated. However, the functions of ubiquitinated Rab proteins remain unexplored. Here we show that Rab5 is monoubiquitinated on K116, K140, and K165. Upon co-transfection with ubiquitin, Rab5 exhibited abnormalities in endosomal localization and EGF-induced EGF receptor degradation. Rab5 K140R and K165R mutants restored these abnormalities, whereas K116R did not. We derived structural
more » ... odels of individual monoubiquitinated Rab5 proteins (mUbRab5s) by solution scattering and observed different conformational flexibilities in a site-specific manner. Structural analysis combined with biochemical data revealed that interactions with downstream effectors were impeded in mUbRab5K140, whereas GDP release and GTP loading activities were altered in mUbRab5K165. By contrast, mUbRab5K116 apparently had no effect. We propose a regulatory mechanism of Rab5 where monoubiquitination downregulates effector recruitment and GDP/GTP conversion in a site-specific manner.
doi:10.7554/elife.29154 pmid:28968219 pmcid:PMC5624781 fatcat:lx3tyud2xvgexnyivrly4keorq

A Novel Cross-Layer Authentication Protocol for the Internet of Things

Yonggu Lee, Jiseok Yoon, Jinho Choi, Euiseok Hwang
2020 IEEE Access  
doi:10.1109/access.2020.3033562 fatcat:2kxdhd77gvhdrhgkpdyl2cx6bm

Colorimetric Detection of Warfare Gases by Polydiacetylenes Toward Equipment-Free Detection

Jiseok Lee, Sungbaek Seo, Jinsang Kim
2012 Advanced Functional Materials  
doi:10.1002/adfm.201102486 fatcat:xayxjlwblbgsje45ypaoat4wxy

Universal process-inert encoding architecture for polymer microparticles

Jiseok Lee, Paul W. Bisso, Rathi L. Srinivas, Jae Jung Kim, Albert J. Swiston, Patrick S. Doyle
2014 Nature Materials  
Polymer microparticles with unique, decodable identities are versatile information carriers with a small footprint. Widespread incorporation into industrial processes, however, is limited by a trade-o between encoding density, scalability and decoding robustness in diverse physicochemical environments. Here, we report an encoding strategy that combines spatial patterning with rare-earth upconversion nanocrystals, single-wavelength near-infrared excitation and portable CCD (charge-coupled
more » ... -based decoding to distinguish particles synthesized by means of flow lithography. This architecture exhibits large, exponentially scalable encoding capacities (>10 6 particles), an ultralow decoding false-alarm rate (<10 −9 ), the ability to manipulate particles by applying magnetic fields, and pronounced insensitivity to both particle chemistry and harsh processing conditions. We demonstrate quantitative agreement between observed and predicted decoding for a range of practical applications with orthogonal requirements, including covert multiparticle barcoding of pharmaceutical packaging (refractive-index matching), multiplexed microRNA detection (biocompatibility) and embedded labelling of high-temperaturecast objects (temperature resistance).
doi:10.1038/nmat3938 pmid:24728464 fatcat:bsfcvj5npvcsnjpjfrujd5uxnm

An automated homecage system for multiwhisker detection and discrimination learning in mice [article]

Sarah M Bernhard, Jiseok Lee, Mo Zhu, Alex Hsu, Andrew Erskine, Samuel A Hires, Alison L. Barth
2020 bioRxiv   pre-print
Automated, homecage behavioral training for rodents has many advantages: it is low stress, requires little interaction with the experimenter, and can be easily manipulated to adapt to different experimental condition. We have developed an inexpensive, Arduino-based, homecage training apparatus for sensory association training in freely-moving mice using multiwhisker air current stimulation coupled to a water reward. Animals learn this task readily, within 1-2 days of training, and performance
more » ... ogressively improves with training. We examined the parameters that regulate task acquisition using different stimulus intensities, directions, and reward valence. Learning was assessed by comparing anticipatory licking for the stimulus compared to the no-stimulus (blank) trials. At high stimulus intensities (>9 psi), animals showed markedly less participation in the task. Conversely, very weak air current intensities (1-2 psi) were not sufficient to generate rapid learning behavior. At intermediate stimulus intensities (5-6 psi), a majority of mice learned that the multiwhisker stimulus predicted the water reward after 24-48 hrs of training. Both exposure to isoflurane and lack of whiskers decreased animals' ability to learn the task. Perceptual learning was assessed and following training at an intermediate stimulus intensity, perception was likely heightened as mice were able to transfer learning behavior when exposed to the lower stimulus intensity. Mice learned to discriminate between two directions of stimulation rapidly and accurately, even when the angular distance between the stimuli was <15 degrees. Switching the reward to a more desirable reward, aspartame, had little effect on learning trajectory. Our results show that a tactile association task in an automated homecage environment can be monitored by anticipatory licking to reveal rapid and progressive behavioral change. These Arduino-based, automated mouse cages enable high-throughput training that facilitate analysis of large numbers of genetically modified mice with targeted manipulations of neural activity.
doi:10.1101/2020.04.27.063750 fatcat:wqr2dwxgcrfs7ietva7anqngpy
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