Size effect on nanomechanical properties of ZnO cones using in situ transmission electron microscopy

Shao-Hui Kang,Te-Hua Fang,Tao-Hsing Chen,Ching-Hong Kuo 한국물리학회 2013 Current Applied Physics Vol.13 No.8

Nanoscale fracture and strain-induced structure variation of ZnO nanocones are determined using in situ transmission electron microscopy compression experiments. For the single-crystalline nanocones with diameters of 100-300 nm, the Young’s modulus is in the range of 7.7-48 GPa and the ultimate tensile strength is in the range of 2.4-4.3%. The Young’s modulus and tensile strength increase with decreasing diameter. Here, we report the nanogenerator of ZnO nanocones can be used mechanical energy to output 90 nW/mm2

Replication of butterfly wing microstructures using molding lithography

Shao-Hui Kang,Tzu-Yao Tai,Te-Hua Fang 한국물리학회 2010 Current Applied Physics Vol.10 No.2

This study employed a soft lithography technique to fabricate a polydimethylsiloxane (PDMS) replica of the multi-layered scales on the upper surface of a Morpho butterfly. The bionic photonic crystal microstructure of the replicated scales was examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The absorptivity, reflectivity and fluorescent characteristics of the wing were measured. The results showed that the microstructural and optical characteristics of the replicated wing qualitatively agree with those of the actual wing. The contact angle for the natural wing structure and the replicated wing were about 143˚ and 120˚, respectively. As a result, it can be inferred that the soft lithography technique employed in this study represents a viable approach for the mass production of artificial photonic crystal structures for a variety of commercial applications, including optical elements for computing and communications purposes, photonic integrated circuits, anti-counterfeiting mechanisms, and so forth.

Inhibition of Proliferation and Induction of Apoptosis by the Combination of β-carotene and 1,25-dihydroxyvitamin D3 in Human Esophageal Cancer EC9706 Cells

Wang, Shao-Kang,Yang, Lei,Wang, Ting-Ting,Huang, Gui-Ling,Yang, Li-Gang,Sun, Gui-Ju Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

Esophageal cancer is a common malignant tumor occurring in human esophageal epithelial tissue. The primary purpose of this paper was to define the effects of ${\beta}$-carotene and 1,25-dihydroxyvitamin $D_3$, alone and in combination, on cell proliferation, cell cycle and apoptosis of human esophageal cancer EC9706 cells. Treatment with different concentrations of ${\beta}$-carotene and/or 1,25-dihydroxyvitamin $D_3$. MTT assay showed that ${\beta}$-carotene and 1,25-dihydroxyvitamin $D_3$ significantly inhibited proliferation of EC9706 cells in a dose- and time-dependent manner. Further studies also demonstrated that ${\beta}$-carotene alone or 1,25-dihydroxyvitamin $D_3$ alone caused a marked increase on the induction of apoptosis in EC9706 cells. The percentage of G0/G1-phase cells significantly increased on addition of 1,25-dihydroxyvitamin $D_3$ alone, but there were no significant changes with ${\beta}$-carotene alone. These two agents in combination synergistically inhibited cell growth and induced apoptosis. Therefore, our results indicate that ${\beta}$-carotene and 1,25-dihydroxyvitamin $D_3$ in combination may provide a novel strategy for preventing and treating esophageal cancer.

지령 30 집 기념호 : 축사 - 《 중국어문학 》 출판 30 주기를 축하하며 -

장소강(Shao Kang Zhang) 영남중국어문학회 1997 중국어문학 Vol.30 No.1

Cell–cell adhesion in metazoans relies on evolutionarily conserved features of the α-catenin·β-catenin–binding interface

Shao, Xiangqiang,Kang, Hyunook,Loveless, Timothy,Lee, Gyu Rie,Seok, Chaok,Weis, William I.,Choi, Hee-Jung,Hardin, Jeff American Society for Biochemistry and Molecular Bi 2017 The Journal of biological chemistry Vol.292 No.40

<P>Stable tissue integrity during embryonic development relies on the function of the cadherin center dot catenin complex (CCC). The Caenorhabditis elegans CCC is a useful paradigm for analyzing in vivo requirements for specific interactions among the core components of the CCC, and it provides a unique opportunity to examine evolutionarily conserved mechanisms that govern the interaction between alpha- and beta-catenin. HMP-1, unlike its mammalian homolog alpha-catenin, is constitutively monomeric, and its binding affinity for HMP-2/beta-catenin is higher than that of alpha-catenin for beta-catenin. A crystal structure shows that the HMP-1 center dot HMP-2 complex forms a five-helical bundle structure distinct from the structure of the mammalian alpha-catenin beta-catenin complex. Deletion analysis based on the crystal structure shows that the first helix of HMP-1 is necessary for binding HMP-2 avidly in vitro and for efficient recruitment of HMP-1 to adherens junctions in embryos. HMP-2 Ser-47 and Tyr-69 flank its binding interface with HMP-1, and we show that phosphomimetic mutations at these two sites decrease binding affinity of HMP-1 to HMP-2 by 40-100-fold in vitro. In vivo experiments using HMP-2 S47E and Y69E mutants showed that they are unable to rescue hmp-2(zu364) mutants, suggesting that phosphorylation of HMP-2 on Ser-47 and Tyr-69 could be important for regulating CCC formation in C. elegans. Our data provide novel insights into how cadherin-dependent cell-cell adhesion is modulated in metazoans by conserved elements as well as features unique to specific organisms.</P>

Structural and functional characterization of <i>Caenorhabditis elegans</i> α-catenin reveals constitutive binding to β-catenin and F-actin

Kang, Hyunook,Bang, Injin,Jin, Kyeong Sik,Lee, Boyun,Lee, Junho,Shao, Xiangqiang,Heier, Jonathon A.,Kwiatkowski, Adam V.,Nelson, W. James,Hardin, Jeff,Weis, William I.,Choi, Hee-Jung American Society for Biochemistry and Molecular Bi 2017 The Journal of biological chemistry Vol.292 No.17

<P>Intercellular epithelial junctions formed by classical cadherins, beta-catenin, and the actin-binding protein alpha-catenin link the actin cytoskeletons of adjacent cells into a structural continuum. These assemblies transmit forces through the tissue and respond to intracellular and extracellular signals. However, the mechanisms of junctional assembly and regulation are poorly understood. Studies of cadherin-catenin assembly in a number of metazoans have revealed both similarities and unexpected differences in the biochemical properties of the cadherin center dot catenin complex that likely reflect the developmental and environmental requirements of different tissues and organisms. Here, we report the structural and biochemical characterization of HMP-1, the Caenorhabditis elegans alpha-catenin homolog, and compare it with mammalian alpha-catenin. HMP-1 shares overall similarity in structure and actin-binding properties, but displayed differences in conformational flexibility and allosteric regulation from mammalian alpha-catenin. HMP-1 bound filamentous actin with an affinity in the single micromolar range, even when complexed with the beta-catenin homolog HMP-2 or when present in a complex of HMP-2 and the cadherin homolog HMR-1, indicating that HMP-1 binding to F-actin is not allosterically regulated by the HMP-2.HMR-1 complex. The middle (i.e. M) domain of HMP-1 appeared to be less conformationally flexible than mammalian alpha-catenin, which may underlie the dampened effect of HMP-2 binding on HMP-1 actin-binding activity compared with that of the mammalian homolog. In conclusion, our data indicate that HMP-1 constitutively binds beta-catenin and F-actin, and although the overall structure and function of HMP-1 and related alpha-catenins are similar, the vertebrate proteins appear to be under more complex conformational regulation.</P>

Renal-protective effects of <i>n</i>-hexane layer from morning glory seeds ethanol extract

Shao, Yanli,Park, Bongkyun,Song, Yoon-Jae,Park, Dae Won,Sohn, Eun-Hwa,Kang, Se Chan Elsevier 2017 Biomedicine & pharmacotherapy Vol.95 No.-

<P><B>Abstract</B></P> <P>Nephrotoxicity is a main problem in cancer patients using cisplatin. Oxidative stress, inflammation and apoptosis are the important mechanisms of cisplatin induced nephrotoxicity. In the present study, we investigated the effect of the extracts of morning glory on nephrotoxicity by cisplatin in human embryonic kidney cells 293 (HEK-293) and mice. Previous studies have reported that morning glory extracts showed potent activity on anti-inflammatory and anti-oxidant. However, the protective effects of the <I>n</I>-hexane layer of morning glory seed (MGs-Hx) on nephrotoxicity and its mechanisms have not been clearly understood. Oral administration with MGs-Hx showed protective effects <I>in vivo</I> experiments test and the treatment of MGs-Hx in a concentration of 100mg/kg/day had significant effect both of decreasing serum creatinine, BUN, serum uric acid level and reduced iNOS, COX-2 mRNA expressions with low side-effect. Moreover, cell viability was restored by MGs-Hx treatment compared to cisplatin-induced nephrotoxic HEK-293 cells. Co-treatment with MGs-Hx and cisplatin showed the significant effect to reduce inflammatory enzyme, iNOS expression and continuous production of NO. In addition, it exhibited a tendency to decreasing expression of apoptosis-related proteins, caspase-3, 8 and 9, and NF-κB translocation to nucleus as well as phosphorylation of p38, JNK, ERK in cisplatin-induced nephrotoxic HEK-293 cells. Our study provides insight into the underlying mechanisms of MGs-Hx and suggests that MGs-Hx might be a potential therapeutic agent to modulate inflammation and apoptosis in nephrotoxicity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The present study aimed to evaluate protective effect of MGs-Hx on cisplatin-induced nephrotoxicity. </LI> <LI> MGs-Hx inhibited BUN, creatinine and uric acid levels in cispaltin-induced renal injury mice. </LI> <LI> MGs-Hx attenuated the cisplatin-induced inflammation and apoptosis in HEK-293 cells. </LI> <LI> Renoprotective effects of MGs-Hx were accompanied by suppression of MAPKs. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Sol-gel synthesis of photoactive zirconia-titania from metal salts and investigation of their photocatalytic properties in the photodegradation of methylene blue

Shao, Godlisten N.,Imran, S.M.,Jeon, Sun Jeong,Engole, Marion,Abbas, Nadir,Salman Haider, M.,Kang, Shin Jae,Kim, Hee Taik Elsevier 2014 Powder technology Vol.258 No.-

Photoactive metal oxide systems capable of reducing non-biodegradable pollutants are highly needed heterogeneous catalysts for environmental purification. Most of the currently available heterogeneous catalysts are obtained from complicated synthetic routes using expensive and perhaps hazardous precursors. The present study reports a novel sol-gel method to synthesize pure TiO2 and ZrO2-TiO2 samples using titanium oxychloride as TiO2 precursor and zirconyl nitrate hydrate as a ZrO2 source in the presence of the surfactant. The ratio of Zr-to-Ti was controlled between 0.75 and 3.2 to evaluate the effect of the amount of ZrO2 in the composites. Consequently, the precipitates were calcined at different temperatures to investigate the effect of removing the template at different sintering temperatures. The physico-chemical properties of the samples were examined by SEM, HRTEM, DT-TGA, XRD, FTIR, XRF, EDX, nitrogen gas physisorption and UV-visible diffusive reflectance spectrometry analyses. These analyses revealed that the crystallization, dispersion, particle size and shape of the samples are critically dependent upon the calcination temperatures and Zr-to-Ti ratios. Abnormal grain growth (AGG) was unexpectedly observed in the samples calcined at higher temperatures (<= 800 degrees C). Comparisons of the activities of the samples toward decolorization of methylene blue indicated that the photocatalytic efficiencies of the composites with Zr/ri <= 2.2 were superior to that of pure TiO2. (C) 2014 Elsevier B.V. All rights reserved.

Parametric Investigation of BOG Generation for Ship-to-Ship LNG Bunkering

Shao, Yude,Lee, Yoon-Hyeok,Kim, You-Taek,Kang, Ho-Keun The Korean Society of Marine Environment and safet 2018 해양환경안전학회지 Vol.24 No.3

As a fuel for ship propulsion, liquefied natural gas (LNG) is currently considered a proven and reasonable solution for meeting the IMO emission regulations, with gas engines for the LNG-fueled ship covering a broad range of power outputs. For an LNG-fueled ship, the LNG bunkering process is different from the HFO bunkering process, in the sense that the cryogenic liquid transfer generates a considerable amount of boil-off gas (BOG). This study investigated the effect of the temperature difference on boil-off gas (BOG) production during ship-to-ship (STS) LNG bunkering to the receiving tank of the LNG-fueled ship. A concept design was resumed for the cargo/fuel tanks in the LNG bunkering vessel and the receiving vessel, as well as for LNG handling systems. Subsequently, the storage tank capacities of the LNG were $4,500m^3$ for the bunkering vessel and $700m^3$ for the receiving vessel. Process dynamic simulations by Aspen HYSYS were performed under several bunkering scenarios, which demonstrated that the boil-off gas and resulting pressure buildup in the receiving vessel were mainly determined by the temperature difference between bunkering and the receiving tank, pressure of the receiving tank, and amount of remaining LNG.

Study on the Variation of LNG Composition in Bunker Tank of Neo-Panamax Otto Cycle LNG Dual Fueled Container Ship

Yude Shao,Sang-Deuk Yoon,Seung-Hun Lee,Ho-Keun Kang 한국가스학회 2019 한국가스학회 학술대회논문집 Vol.2019 No.5