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Fabrication of ferroelectric Bi4Ti3O12 thin films was carried out by dipping pyrolysis of metal naphthenates. Single-phase Bi4Ti3O12 thin films with c-axis orientation perpendicular to the substrate surface were fabricated on Pt plates. They exhibited good ferroelectric properties: coercive field of 7.7 kV/cm and remanent polarization of 8.2 µ C/cm2. For the films fabricated on Pt/Ti/ SiO2/Si substrates, however, the Bi2Ti2O7 phase mainly grew because of Ti diffusion into the bismuth titanate layer during the heat treatment. Fine micropatterns with linewidth of less than 1 µ m in precursors of Bi4Ti3O12 were formed by spin-coating, irradiation with an electron beam and development. They were crystallized into the Bi4Ti3O12 phase by successive pyrolysis and annealing. The reaction between the metal naphthenate films and energized electrons was studied by IR spectroscopic analysis.

Summary The majority of cells in early/colostrum milk are breast milk macrophages (BrMMø) expressing dendritic cell (DC)‐specific intercellular adhesion molecule 3 (ICAM3) grabbing nonintegrin (DC‐SIGN), and the expression level of DC‐SIGN on BrMMø will determine cell‐to‐cell human immunodeficiency virus type 1 (HIV‐1) transmissibility. Thus, one of the strategies to prevent vertical transmission of HIV‐1 through breast‐feeding is to find a way to suppress DC‐SIGN expression on BrMMø. As for the expression of Toll‐like receptors (TLRs) in BrMMø, TLR3 was always seen in BrMMø but not in peripheral blood monocytes (PBMo). Also, the expression of TLR3 was slightly enhanced in BrMMø when the cells were treated with interleukin (IL)‐4. Moreover, when TLR3 was stimulated with its specific ligand, the double‐stranded RNA (dsRNA) poly(I:C), DC‐SIGN expression on BrMMø was reduced even in the IL‐4‐mediated enhanced state. Some reduction may be caused by type I interferons (IFNs), such as IFN‐α/β, secreted from BrMMø. Indeed, both IFNs, particularly IFN‐β, showed a strong capacity to suppress the enhancement of DC‐SIGN expression on IL‐4‐treated BrMMø and such TLR3‐mediated DC‐SIGN suppression was partially abrogated by the addition of anti‐IFN‐α/β‐receptor‐specific antibodies. As expected, DC‐SIGN‐mediated HIV‐1 transmission to CD4‐positive cells by BrMMø was inhibited by either poly(I:C) stimulation or by treatment with type I IFNs. These findings suggest a possible strategy for preventing mother‐to‐child transmission (MTCT) of HIV‐1 via breast‐feeding through TLR3 signalling.

Zn 1Àx Mn x )O diluted magnetic semiconductors (DMSs) grown on (0001) Al 2 O 3 substrates by radio frequency magnetron sputtering were investigated with the aim of producing a material with a high ferromagnetic transition temperature (T c ). X-ray diffraction, photoluminescence, and Hall-effect measurements showed that the grown (Zn 1Àx Mn x )O thin films were p-type crystalline semiconductors with single phases. Magnetization curve as a function of magnetic field at 5 K indicated that ferromagnetism existed in the (Zn 1Àx Mn x )O thin films, and magnetization curve as a function of temperature showed that the T c of the (Zn 0:93 Mn 0:07 )O thin film was 70 K. These observations can improve the understanding of the increase in T c for (Zn 1Àx Mn x )O DMSs grown on (0001) Al 2 O 3 substrates.

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