Hematopoietic stem cells rarely contribute to hepatic regeneration, however, the mechanisms governing their homing to the liver, which is a crucial first step, are poorly understood. The chemokine stromal cell-derived factor-1 (SDF-1), which attracts human and murine progenitors, is expressed by liver bile duct epithelium. Neutralization of the SDF-1 receptor CXCR4 abolished homing and engraftment of the murine liver by human CD34 + hematopoietic progenitors, while local injection of human SDF-1 increased their homing. Engrafted human cells were localized in clusters surrounding the bile ducts, in close proximity to SDF-1-expressing epithelial cells, and differentiated into albumin-producing cells. Irradiation or inflammation increased SDF-1 levels and hepatic injury induced MMP-9 activity, leading to both increased CXCR4 expression and SDF-1-mediated recruitment of hematopoietic progenitors to the liver. Unexpectedly, HGF, which is increased following liver injury, promoted protrusion formation, CXCR4 upregulation, and SDF-1-mediated directional migration by human CD34 + progenitors, and synergized with stem cell factor. Thus, stress-induced signals, such as increased expression of SDF-1, MMP-9, and HGF, recruit human CD34 + progenitors with hematopoietic and/or hepatic-like potential to the liver of NOD/SCID mice. Our results suggest the potential of hematopoietic CD34 + /CXCR4 + cells to respond to stress signals from nonhematopoietic injured organs as an important mechanism for tissue targeting and repair.

with yttrium, barium, copper acetates as starting materials, a low-fluorine-content solution was prepared. YBa2Cu3O7-x (YBCO) films on LaAlO3 (LAO) single crystal substrates were fabricated by a new TFA-MOD method. Solution-derived YBCO films exhibited epitaxial growth, which was confirmed by X-ray diffraction (XRD). The humidity of the furnace atmosphere during annealing process influences the texture of YBCO film. Under high-humidity of furnace atmosphere, a-oriented grains, which were confirmed by scanning electron microscopy (SEM), were generated on film surface. High-resolution transmission electron microscopy (HRTEM), however, indicated that although a-axis oriented grains formed on the film surface, c-axis oriented grains occupied the area near the YBCO/LAO interface. High-performance YBCO films with Tc above 90K, and Jc more than 106A/cm2 at 77 K and zero magnetic field were obtained.

precursor solution was prepared using barium trifluoroacetae (Ba-TFA) and non-fluorine yttrium (Y) and copper (Cu) organic salts. The precursor solution was modified by benzalacetone (BzAcH), in which the Cu2+ were chelated with BzAcH, which preventing the loss of Cu in the pyrolysis process. Dense YBCO superconducting films with smooth surface, which confirmed by scanning electron microscopy (SEM), were repeatedly obtained through sol-gel process. X-ray diffraction (XRD) 2θ scanning and φ scanning indicated that the as-prepared YBCO films had good c-axis texture. YBCO films with superconducting transition temperature (TC) above 89K were obtained.

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Using La(NO3)3•nH2O and Ni(CH3COO)2•4H2O as starting materials, alcohol mixed with methoxyethanol as solvent, the LaNiO3 (LNO) solution was prepared. Using this solution, conducting LNO films with sheet resistance of 10Ω were obtained. XRD and HRTEM indicate that the LNO films are epitaxially grown on LaAlO3 (LAO) substrates. Using Pb(CH3COO)2•3H2O, La(NO3)3•nH2O, Ti(OC4H9)4, Zr(OC4H9)4 as starting materials, the PZT films were prepared on the LNO films. The PZT films are c-oriented. The as-prepared PZT film has a remanent polarization of 34.7µC/cm2, superior to the PZT film with random orientation and a remanent polarization of 18.4µC/cm2 prepared on ITO/quartz substrate.

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Using a low-fluorine solution, YBa2Cu3O7-x (YBCO) superconducting films were prepared on LaAlO3 (LAO) substrates by dip-coating method. YBCO films were fired at different temperatures with same oxygen pressure of 1.3 vol% and water vapor pressure of 7.4 vol%. Effect of firing temperature on film microstructure and superconductivity was investigated. The results indicated that YBCO films with high-degree c-axis orientation (the degree of c-axis orientation reached 96%) can be obtained when heat treated at 800 °C. At this temperature YBCO films were grown on LAO with cubic-on-cubic mode, resulting in a high critical transition temperature (Tc) of 91.5 K, and critical current density (Jc) of lager than 1 MA/cm2. However, when fired at lower temperatures, YBCO films trended to form a-axis grains, which degraded Jc of films. And a higher heat treatment temperature also depressed superconductivityof YBCO films.

Ni0.5Zn0.5Fe2O4-Pb(Zr0.52Ti0.48)O3 (NZFO-PZT) composite films were prepared using sol–gel method on Si (100) substrate with different bilayer structures, namely, the NZFO/PZT (NP) and the PZT/NZFO (PN). Their structure, magnetic and ferroelectric properties were characterized by X-ray diffractometer (XRD), vibration sample magnetometer (VSM) and ferroelectric testing unit. Both the NP and the PN films exhibit coexistence of magnetic and ferroelectric properties. The overlapping sequence has much influence on the electrical properties. Whereas, such an overlapping structure of the films has slightly effect on its magnetic properties. The NP structured composite film is more suitable to get a promising magnetoelectric coupling.