The role of local non-tetragonal polar displacements in the temperature- and pressure-induced phase transitions in PbTiO-BiMeO ferroelectrics.

In situ high-pressure/high-temperature Raman-scattering analyses on PbTiO , 0.92PbTiO 0.08Bi(Zn Ti )O and 0.

Influence of pemphigoid gestationis on pregnancy outcome: A case report and review of the literature.

Pemphigoid gestationis is considered to be a rare pregnancy exclusive bullous disease, which modifies the course of the pregnancy, with difficulties in the management of the pruritus and skin lesions as well as a possible change in the neonatal outcome. Differential diagnosis of skin lesions and pruritus in pregnancy is challenging, and complementary investigations such as skin biopsy or laboratory tests are indispensable. The correct diagnosis and proper treatment could change the natural course of a pregnancy at risk and could improve maternal and fetal morbidity.

Stochastic Polarization Instability in PbTiO_{3}.

Although discussions of structural phase transitions in prototypical ferroelectric systems with the perovskite structure, such as BaTiO_{3} and PbTiO_{3}, started almost seventy years ago, an atomic-level description of the polar characteristics as a function of temperature, pressure, and composition remains topical. Here we provide a novel quantitative description of the temperature-driven local structural correlations in PbTiO_{3} via the development of characteristic relative cationic shifts. The results give new insights into the phase transition beyond those reliant on the long-range order.

Multistep coupling of preexisting local ferroic distortions in PbTiO above the Curie temperature.

Temperature-dependent Raman spectroscopic analyses were performed for the prominent ferroelectric PbTiO in the temperature range 130-1040 K, focusing particularly on its paraelectric state above the Curie temperature [Formula: see text] K. The temperature evolution of the anomalous Raman scattering reveals that not only local ferroic distortions persist at temperatures well above [Formula: see text], but also there is a sequence of different coupling processes preceding the appearance of long-range ferroelectric order at [Formula: see text]. Our results indicate that, similar to relaxor ferroelectrics, the paraelectric phase of PbTiO can be considered as an ergodic system of local ferroic distortions, which only on average appears to have cubic symmetry.