Biodegradable Poly(lactic-co-glycolic acid) Maxpol-T/S as Novel Scaffold for Adipose Derived Stem Cells and Fibroblast Growth In Vitro

( Zhe Jin ),( Yan Qing Gong ),( Xin Cheng Qin ),( Jian Zhang ),( Yi Chen Zhu ),( Gui Ting Lin ),( Tom F Lue ),( Zhong Cheng Xin ) 한국조직공학·재생의학회 2008 조직공학과 재생의학 Vol.5 No.4

To explore the ability of MaxPol-T/S, a novelbiodegradable poly-lactic-co-glycolic acid(PLGA) scaffold, in providing a cell-matrix interaction interface for cell growth, we generated GFP positive adipose derived stem cell(ADSCGFP+) and fibroblasts(FCGFP+) for investigating the cellular growth on this biomaterial. The MaxPol-T/S was produced through salt-leaching/particulate-leaching technology for tissue engineering, which provides a modified surface for the best cellular attachment sites and nutrient supply and waste exchange conditions. The morphological features of MaxPol-T/S were studied with a scanning electron microscope and the ADSCGFP+ and FCGFP+ were confirmed by auto-fluorescence microscopy and flow cytometry assay. Being seeded onto the MaxPol-T/S in vitro, the growth and morphology of ADSCGFP+ and FCGFP+ were further verified by auto-fluorescence microscopy and MMT test. The ADSCs and fibroblasts, expressed strong GFP signals in the cytoplasm and nucleus, adhered and proliferated on the surface of scaffold MaxPol-T/S. Both cell lines survived on the scaffold more than 21 days in vitro and formed three-dimensional colonies on the surface of the MaxPol-T. In conclusion, MaxPol-T/S is a novel PLGA scaffold for ADSCGFP+ and FCGFP+ and implies a promising technique for tissue engineering.

Characteristics of Metal-ferroelectric-insulator-semiconductor Diodes Using a Dysprosium-zirconium-oxide Film as a Buffer Layer

임종현,Gui-Zhe An,박병은 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.51

To fabricate a metal-ferroelectric-insulator-semiconductor (MFIS) structure, we prepared a (Bi,La)_4Ti_3O_(12) (BLT) film as a ferroelectric layer and a dysprosium-zirconium-oxide (DZO) thin film as an insulating buffer layer on a p-type Si (100) wafer by using a sol-gel method. Equivalent oxide thickness (EOT) values of the DZO thin films deposited on Si were about 12.4 nm, 11.9 nm, 11.2 nm, and 11.1 nm for 650 ℃, 700 ℃, 750 ℃, and 800 ℃, respectively. The leakage current densities showed good characteristics, regardless of annealing temperature variations. In case of the 750 ℃-annealed DZO thin film, a negligible hysteresis width (Δ<i>V<SUB>FB</SUB></i>) was observed. The capacitance-voltage (C-V) characteristics of the 300-nm-thick BLT film on the 750 ℃-annealed DZO/Si structure showed clockwise hysteresis loops, and the memory window width increased as the bias sweep voltage increased. The maximum value of the memory window width was about 1.9 V at a bias sweep voltage of ±7 V, and the leakage current density was lower than 5 × 10^(−7) A/cm^2 at 5 V.

Optimal Design for Cooling System of Batteries Using DOE and RSM

Zhen-Zhe Li,Yun-De Shen,Tai-Hong Cheng,Dong-Ji Xuan,Ming Ren,Gui-Ying Shen 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.

A hybrid power composed of fuel cell and batteries has become the good strategy for HEV. On the contrary, the produced heat of batteries can affect to the total performance of HEV significantly. In this study, simulation methods with optimization were developed for obtaining the high performance cooling system of batteries. At first, a numerical method for obtaining the temperature distribution of batteries was developed by using CFD. In the following step, several parameters were investigated for selecting design variables with the important effect on the performance of the cooling system of batteries. Finally, an optimization method based on DOE and RSM was obtained through a real optimal design. There was 21.1% reduction on the view of the root mean square temperature between batteries as shown in the optimization result. The developed analysis with optimization can be used to improve the performance of the cooling system of batteries, and these works have made the theoretical basis for simulation and optimization of the cooling system of batteries.

Electrical properties of metal-ferroelectric-insulator-semiconductor structure with Lanthanum Dysprosium Oxide and SrBi_2Ta_2O_9

임종현,Kwi-Jung Kim,Gui-Zhe An,박병은 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.31

The metal-ferroelectric-insulator-semiconductor (MFIS) structure using SrBi_2Ta_2O_9 (SBT) film as a ferroelectric layer and lanthanum dysprosium oxide (LDO) film as an insulating buffer layer was prepared. The LDO thin film and SBT film were deposited by sol-gel method. The sol-gel derived LDO thin films on Si had very flat and smooth surface morphologies. The equivalent oxide thickness (EOT) values were about 10.1 nm, 12.5 nm, and 12.8 nm for 750 ˚C, 800 ˚C, and 850 ˚C, respectively. Also, the relative dielectric constant of 750 °C-annealed, 800 °C-annealed and 850 °C-annealed LDO films were about 15.4, 12.5, and 12.2, respectively. On the whole, the leakage current densities showed the good characteristics regardless of the annealing temperature variations. Especially, the leakage current property of the 850 °C-annealed LDO film was visibly superior to the others over 6V. The C-V characteristics of Au/SBT/LDO/Si structure showed clockwise hysteresis loops, and the memory window width increased as the bias voltage increased. Also, the leakage current density was lower than 5 ×10^(-7) A/cm^2

Self-Limiting Electrodeposition of Hierarchical MnO₂ and M(OH)₂/MnO₂ Nanofibril/Nanowires: Mechanism and Supercapacitor Properties

Duay, Jonathon,Sherrill, Stefanie A.,Gui, Zhe,Gillette, Eleanor,Lee, Sang Bok American Chemical Society 2013 ACS NANO Vol.7 No.2

<P>Hierarchical nanostructures have generated great interest in the energy, materials, and chemical sciences due to the synergic properties of their composite architectures. Herein, a hierarchical MnO<SUB>2</SUB> nanofibril/nanowire array is successfully synthesized. The structure consists of a conformal layer of MnO<SUB>2</SUB> nanofibrils evenly distributed on the surface of the individual MnO<SUB>2</SUB> nanowires. The synthetic mechanism of this hierarchical structure is characterized by electrochemical measurements, Raman spectroscopy, EELS, and electron microscopy. This material was then investigated at slow scan rates for its charge storage mechanisms in different solvents. In aqueous electrolyte, the nanofibrils show a capacitance almost purely dedicated to double-layer and surface adsorption processes, while in an acetonitrile electrolyte, the nanofibrils’ capacitance comes mainly from a cation insertion process. This material was also tested at high scan rates in aqueous solution for its practical supercapacitor capabilities. The material shows a large capacitance of 298 F/g at 50 mV/s and 174 F/g at 250 mV/s. It also maintains 85.2% of its capacitance after 1000 cycles. The material also displays easily controllable parameters such as nanowire length, nanowire diameter, and amount of nanofibril material which is shown here to affect the capacitance dramatically.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2013/ancac3.2013.7.issue-2/nn3056077/production/images/medium/nn-2012-056077_0014.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn3056077'>ACS Electronic Supporting Info</A></P>

MnO₂/TiN heterogeneous nanostructure design for electrochemical energy storage

Sherrill, Stefanie A.,Duay, Jonathon,Gui, Zhe,Banerjee, Parag,Rubloff, Gary W.,Lee, Sang Bok Royal Society of Chemistry 2011 Physical chemistry chemical physics Vol.13 No.33

<P>MnO<SUB>2</SUB>/TiN nanotubes are fabricated using facile deposition techniques to maximize the surface area of the electroactive material for use in electrochemical capacitors. Atomic layer deposition is used to deposit conformal nanotubes within an anodic aluminium oxide template. After template removal, the inner and outer surfaces of the TiN nanotubes are exposed for electrochemical deposition of manganese oxide. Electron microscopy shows that the MnO<SUB>2</SUB> is deposited on both the inside and outside of TiN nanotubes, forming the MnO<SUB>2</SUB>/TiN nanotubes. Cyclic voltammetry and galvanostatic charge–discharge curves are used to characterize the electrochemical properties of the MnO<SUB>2</SUB>/TiN nanotubes. Due to the close proximity of MnO<SUB>2</SUB> with the highly conductive TiN as well as the overall high surface area, the nanotubes show very high specific capacitance (662 F g<SUP>−1</SUP> reported at 45 A g<SUP>−1</SUP>) as a supercapacitor electrode material. The highly conductive and mechanically stable TiN greatly enhances the flow of electrons to the MnO<SUB>2</SUB> material, while the high aspect ratio nanostructure of TiN creates a large surface area for short diffusion paths for cations thus improving high power. Combining the favourable structural, electrical and energy properties of MnO<SUB>2</SUB> and TiN into one system allows for a promising electrode material for supercapacitors.</P> <P>Graphic Abstract</P><P>Atomic layer deposition and electrochemical deposition are combined to fabricate MnO<SUB>2</SUB>/TiN heterogeneous nanostructures for electrochemical energy storage. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1cp21815h'> </P>

Seroprevalence of Encephalitozoon cuniculi and Toxoplasma gondii in domestic rabbits (Oryctolagus cuniculus) in China

Qing-Feng Meng,Wei-Lin Wang,Xiao-Ting Ni,Hai-Bin Li,Gui-Zhe Yao,Xiao-Lin Sun,Wei-Li Wang,Wei Cong 대한기생충학열대의학회 2015 The Korean Journal of Parasitology Vol.53 No.6

The breeding of domestic rabbits (Oryctolagus cuniculus) for human consumption has a long tradition in China. Infections that can affect the production of meat or even be transmitted from animals to humans are important to monitor, especially for public health reasons as well as for their impact on animal health. Thus, a total of 1,132 domestic rabbit sera from 4 regions in China were collected for serological screening for Encephalitozoon cuniculi and for Toxoplasma gondii by ELISA and modified agglutination test (MAT), respectively. Antibodies to E. cuniculi were detected in 248/1,132 (21.9%) sera tested while antibodies against T. gondii revealed a seroprevalence of 51/1,132 (4.5%). We believe that the present results are of epidemiological implications and public health importance due to the acknowledged susceptibility of humans to E. cuniculi and T. gondii infections. Therefore, routine screening tests of domestic rabbits are proposed considering the zoonotic potential of these parasites.