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Crystalline and ferroelectric properties of nanosized PbTiO3 islands grown at 390 and 560 °C by metalorganic chemical vapor deposition (MOCVD) were investigated by the grazing incidence X-ray diffraction (GIXD) method and piezoresponse scanning force microscopy (PFM). By reducing the growth temperature from 560 to 390 °C, average height of PbTiO3 islands decreased from 19 to 3.6nm while the average width slightly decreased from 49 to 41nm. GIXD measurements revealed that nanosized PbTiO3 islands with the pure perovskite phase were successfully grown at 390 and 560 °C. Preferential orientations of PbTiO3 islands grown at 390 and 560 °C were (001) and (111), respectively. Using PFM, piezoelectric hysteresis loops with polarization reversal were obtained at each individual island. This is evidence for the presence of ferroelectricity in nanosized islands. The minimum island exhibiting ferroelectricity was 1.7 nm high and 38 nm wide. [Copyright &y& Elsevier]

Low-temperature metalorganic chemical vapor deposition (MOCVD) of Pb(Zr,Ti)O3 (PZT) thin films, as low as 370 °C, was successfully achieved. Influence of the crystalline nature of PbTiO3 seeds on crystalline and ferroelectric properties of PZT thin films were investigated. The orientation of PZT thin films and its degree were strongly influenced by those of PbTiO3 seeds. PbTiO3 seeds were very useful to decrease growth temperature of PZT films. The PZT film was successfully obtained at 370 °C only when PbTiO3 seeds were used, exhibiting remanent polarization (2Pr) of 4.2 μC/cm2 and coercive field (2Ec) of 63 kV/cm. [Copyright &y& Elsevier]

Alagille syndrome (AGS) is a congenital multi-system anomaly mainly characterized by paucity of intrahepatic bile ducts caused by haploinsufficiency of the Jagged 1 gene (JAG1). To explore the relationship between genotype and phenotype, we analyzed the JAG1 gene in 25 Japanese AGS families at the genomic DNA level and identified 15 point mutations and one large deletion. Analysis of the genotype and phenotype strongly indicated that the Delta/Serrate/Lag-2 (DSL) domain in JAG1 protein played an essential role in determining the severity of the liver disorder. In four sporadic cases, missing an entire DSL domain in mutant JAG1 resulted in progressive liver failure and all 4 patients needed a liver transplant at a very young age. This correlation was further confirmed by statistical analysis (χ2=9.143, p<0.001). Our finding demonstrated that the DSL domain in JAG1 appears to be essential for normal liver development and function. [ABSTRACT FROM AUTHOR]