Yoon-kyoung Cho - Academia.edu (original) (raw)
Uploads
Papers by Yoon-kyoung Cho
Cells, 2020
The shape of epithelial tissue supports physiological functions of organs such as intestinal vill... more The shape of epithelial tissue supports physiological functions of organs such as intestinal villi and corneal epithelium. Despite the mounting evidence showing the importance of geometry in tissue microenvironments, the current understanding on how it affects biophysical behaviors of cells is still elusive. Here, we cultured cells on various protruded convex structure such as triangle, square, and circle shape fabricated using two-photon laser lithography and quantitatively analyzed individual cells. Morphological data indicates that epithelial cells can sense the sharpness of the corner by showing the characteristic cell alignments, which was caused by actin contractility. Cell area was mainly influenced by surface convexity, and Rho-activation increased cell area on circle shape. Moreover, we found that intermediate filaments, vimentin, and cytokeratin 8/18, play important roles in growth and adaptation of epithelial cells by enhancing expression level on convex structure dependi...
Bookmarks Related papers MentionsView impact
RSC Advances, 2018
Printing nanochannel arrays with controlled cross section size and shape using near-field electro... more Printing nanochannel arrays with controlled cross section size and shape using near-field electrospinning.
Bookmarks Related papers MentionsView impact
Nano Letters, 2019
Bookmarks Related papers MentionsView impact
Acta Biomaterialia, 2018
Bookmarks Related papers MentionsView impact
Lab on a Chip, 2017
Recent advances in microengineered cell migration platforms are discussed critically with focus o... more Recent advances in microengineered cell migration platforms are discussed critically with focus on how cell migration is influenced by engineered tumor microenvironments, the medical relevance being to understand how tumor microenvironments may promote or suppress the progression of cancer.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Encyclopedia of Nanotechnology, 2012
Bookmarks Related papers MentionsView impact
MRS Proceedings, 1996
ABSTRACTWe introduce two new techniques with the sensitivity to measure spectroscopie properties ... more ABSTRACTWe introduce two new techniques with the sensitivity to measure spectroscopie properties of confined molecules under shear. One concerns rheo-optics of fluids in micron-sized gaps. The experimental approach consists in applying periodic shear motion to fluid films confined between parallel plates separated by controllable film thickness from 0.1 to 100 micrometers. A key aspect is the concurrent ability to perform spectroscopie experiments (infrared or dielectric spectroscopy, or x-ray or neutron spectroscopy) of these fluids during flow.The second technique consists in flow field experiments of polymer adsorption and orientation. The experimental approach is to produce one-directional shear, at rates up to 104 sec−1, past adsorbed polymer layers of thickness less than 0.01 micrometers. The selective augmentation of vibrational modes oriented preferentially along the chain backbone is then used to probe chain orientation in the direction of flow in a laminar flow field.
Bookmarks Related papers MentionsView impact
The Analyst, 2015
We report the surface modification of thermoplastic nanochannels and the evaluation of the surfac... more We report the surface modification of thermoplastic nanochannels and the evaluation of the surface charge density, zeta potential and electroosmotic flow (EOF).
Bookmarks Related papers MentionsView impact
Encyclopedia of Nanotechnology, 2012
Bookmarks Related papers MentionsView impact
Encyclopedia of Nanotechnology, 2012
Bookmarks Related papers MentionsView impact
Lab on a chip, Jan 16, 2014
ELISA-based devices are promising tools for the detection of low abundant proteins in biological ... more ELISA-based devices are promising tools for the detection of low abundant proteins in biological samples. Reductions of the sample volume and assay time as well as full automation are required for their potential use in point-of-care diagnostic applications. Here, we present a highly efficient lab-on-a-disc composed of a TiO2 nanofibrous mat for sensitive detection of serum proteins with a broad dynamic range, with only 10 μL of whole blood within 30 min. The TiO2 nanofibers provide high specific surface area as well as active functional groups to capture large amounts of antibodies on the surface. In addition, the device offers efficient mixing and washing for improving the signal-to-noise ratio, thus enhancing the overall detection sensitivity. We employ the device for the detection of cardiac biomarkers, C-reactive protein (CRP) and cardiac troponin I (cTnI), spiked in phosphate-buffered saline (PBS) as well as in serum or whole blood. The device exhibited a wide dynamic range of...
Bookmarks Related papers MentionsView impact
Wear, 1996
To understand the dependence of nanorheology on molecular architecture for perfluorinated molecul... more To understand the dependence of nanorheology on molecular architecture for perfluorinated molecules, studies were performed using two lubricants commonly used in the magnetic storage industry. Experiments mimicked a single asperity by confining liquids to molecular spacings between atomically smooth mica and applying oscillatory shear forces. The force-distance profiles were compared. Large differences were obtained for the linear shear response. The
Bookmarks Related papers MentionsView impact
Tribology International, 1997
Bookmarks Related papers MentionsView impact
Langmuir, 2001
Bookmarks Related papers MentionsView impact
Journal of Polymer Science Part B: Polymer Physics, 1997
Bookmarks Related papers MentionsView impact
The Journal of Chemical Physics, 1999
Bookmarks Related papers MentionsView impact
The Journal of Chemical Physics, 2003
Bookmarks Related papers MentionsView impact
Chemical Society Reviews, 2011
Bookmarks Related papers MentionsView impact
To understand the dependence of nanorheology on molecular architecture for perfluorinated molecul... more To understand the dependence of nanorheology on molecular architecture for perfluorinated molecules, studies were performed using two lubricants commonly used in the magnetic storage industry. Experiments mimicked a single asperity by confining liquids to molecular spacings between atomically smooth mica and applying oscillatory shear forces. The force-distance profiles were compared. Large differences were obtained for the linear shear response. The elastic and dissipative shear moduli of a branched perfluoropolymer (Krytox-AZ) were comparable even at high loads, signifying that the fluid remained fluid-like over experimental frequencies. However, linear perfluoropolymer (Demmim S-20) was easily solidified. The nonlinear responses were also surprising. Previously, we (G. Reiter et al., Science 263 (1994) 1741) reported that the shear-induced transition from an elastic state (at rest) to a dissipative state (during sliding) was discontinuous and hysteric for various hydrocarbon fluids but not for the perfluorinated chain, perfluoroheptaglyme. However, the stick-slip transition was discontinuous, and even more hysteretic for the linear perfluoropolymer (Demnum S-20)
Bookmarks Related papers MentionsView impact
Cells, 2020
The shape of epithelial tissue supports physiological functions of organs such as intestinal vill... more The shape of epithelial tissue supports physiological functions of organs such as intestinal villi and corneal epithelium. Despite the mounting evidence showing the importance of geometry in tissue microenvironments, the current understanding on how it affects biophysical behaviors of cells is still elusive. Here, we cultured cells on various protruded convex structure such as triangle, square, and circle shape fabricated using two-photon laser lithography and quantitatively analyzed individual cells. Morphological data indicates that epithelial cells can sense the sharpness of the corner by showing the characteristic cell alignments, which was caused by actin contractility. Cell area was mainly influenced by surface convexity, and Rho-activation increased cell area on circle shape. Moreover, we found that intermediate filaments, vimentin, and cytokeratin 8/18, play important roles in growth and adaptation of epithelial cells by enhancing expression level on convex structure dependi...
Bookmarks Related papers MentionsView impact
RSC Advances, 2018
Printing nanochannel arrays with controlled cross section size and shape using near-field electro... more Printing nanochannel arrays with controlled cross section size and shape using near-field electrospinning.
Bookmarks Related papers MentionsView impact
Nano Letters, 2019
Bookmarks Related papers MentionsView impact
Acta Biomaterialia, 2018
Bookmarks Related papers MentionsView impact
Lab on a Chip, 2017
Recent advances in microengineered cell migration platforms are discussed critically with focus o... more Recent advances in microengineered cell migration platforms are discussed critically with focus on how cell migration is influenced by engineered tumor microenvironments, the medical relevance being to understand how tumor microenvironments may promote or suppress the progression of cancer.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Encyclopedia of Nanotechnology, 2012
Bookmarks Related papers MentionsView impact
MRS Proceedings, 1996
ABSTRACTWe introduce two new techniques with the sensitivity to measure spectroscopie properties ... more ABSTRACTWe introduce two new techniques with the sensitivity to measure spectroscopie properties of confined molecules under shear. One concerns rheo-optics of fluids in micron-sized gaps. The experimental approach consists in applying periodic shear motion to fluid films confined between parallel plates separated by controllable film thickness from 0.1 to 100 micrometers. A key aspect is the concurrent ability to perform spectroscopie experiments (infrared or dielectric spectroscopy, or x-ray or neutron spectroscopy) of these fluids during flow.The second technique consists in flow field experiments of polymer adsorption and orientation. The experimental approach is to produce one-directional shear, at rates up to 104 sec−1, past adsorbed polymer layers of thickness less than 0.01 micrometers. The selective augmentation of vibrational modes oriented preferentially along the chain backbone is then used to probe chain orientation in the direction of flow in a laminar flow field.
Bookmarks Related papers MentionsView impact
The Analyst, 2015
We report the surface modification of thermoplastic nanochannels and the evaluation of the surfac... more We report the surface modification of thermoplastic nanochannels and the evaluation of the surface charge density, zeta potential and electroosmotic flow (EOF).
Bookmarks Related papers MentionsView impact
Encyclopedia of Nanotechnology, 2012
Bookmarks Related papers MentionsView impact
Encyclopedia of Nanotechnology, 2012
Bookmarks Related papers MentionsView impact
Lab on a chip, Jan 16, 2014
ELISA-based devices are promising tools for the detection of low abundant proteins in biological ... more ELISA-based devices are promising tools for the detection of low abundant proteins in biological samples. Reductions of the sample volume and assay time as well as full automation are required for their potential use in point-of-care diagnostic applications. Here, we present a highly efficient lab-on-a-disc composed of a TiO2 nanofibrous mat for sensitive detection of serum proteins with a broad dynamic range, with only 10 μL of whole blood within 30 min. The TiO2 nanofibers provide high specific surface area as well as active functional groups to capture large amounts of antibodies on the surface. In addition, the device offers efficient mixing and washing for improving the signal-to-noise ratio, thus enhancing the overall detection sensitivity. We employ the device for the detection of cardiac biomarkers, C-reactive protein (CRP) and cardiac troponin I (cTnI), spiked in phosphate-buffered saline (PBS) as well as in serum or whole blood. The device exhibited a wide dynamic range of...
Bookmarks Related papers MentionsView impact
Wear, 1996
To understand the dependence of nanorheology on molecular architecture for perfluorinated molecul... more To understand the dependence of nanorheology on molecular architecture for perfluorinated molecules, studies were performed using two lubricants commonly used in the magnetic storage industry. Experiments mimicked a single asperity by confining liquids to molecular spacings between atomically smooth mica and applying oscillatory shear forces. The force-distance profiles were compared. Large differences were obtained for the linear shear response. The
Bookmarks Related papers MentionsView impact
Tribology International, 1997
Bookmarks Related papers MentionsView impact
Langmuir, 2001
Bookmarks Related papers MentionsView impact
Journal of Polymer Science Part B: Polymer Physics, 1997
Bookmarks Related papers MentionsView impact
The Journal of Chemical Physics, 1999
Bookmarks Related papers MentionsView impact
The Journal of Chemical Physics, 2003
Bookmarks Related papers MentionsView impact
Chemical Society Reviews, 2011
Bookmarks Related papers MentionsView impact
To understand the dependence of nanorheology on molecular architecture for perfluorinated molecul... more To understand the dependence of nanorheology on molecular architecture for perfluorinated molecules, studies were performed using two lubricants commonly used in the magnetic storage industry. Experiments mimicked a single asperity by confining liquids to molecular spacings between atomically smooth mica and applying oscillatory shear forces. The force-distance profiles were compared. Large differences were obtained for the linear shear response. The elastic and dissipative shear moduli of a branched perfluoropolymer (Krytox-AZ) were comparable even at high loads, signifying that the fluid remained fluid-like over experimental frequencies. However, linear perfluoropolymer (Demmim S-20) was easily solidified. The nonlinear responses were also surprising. Previously, we (G. Reiter et al., Science 263 (1994) 1741) reported that the shear-induced transition from an elastic state (at rest) to a dissipative state (during sliding) was discontinuous and hysteric for various hydrocarbon fluids but not for the perfluorinated chain, perfluoroheptaglyme. However, the stick-slip transition was discontinuous, and even more hysteretic for the linear perfluoropolymer (Demnum S-20)
Bookmarks Related papers MentionsView impact