Amino acids nanocrystals for piezoelectric detection of ultra-low mechanical pressure.

Developing biocompatible nano-materials with the ability to detect ultra-low mechanical pressure is promising for biomedical sensors. This paper reports the detection of pressure as low as 1 Pa in the environmental pressure of 1 atm (10% pressure change) by nanocrystals of amino acids glycine and alanine through the piezoelectric effect. Piezoelectricity enables detection of pressure by a change of dielectric polarization when the material is subjected to external pressure.

The stabilization of a single domain in free-standing ferroelectric nanocrystals.

High resolution electron microscopy, electron diffraction and electron holography were used to study individual free-standing ∼ 30 nm barium titanate nanocrystals. Large unidirectional variations in the tetragonal distortion were mapped across the smaller nanocrystals, peaking to anomalously large values of up to 4% at the centers of the nanocrystals. This indicated that the nanocrystals consist of highly strained single ferroelectric domains.

Interpreting Freud: the Yiddish philosophical journal Davke investigates a Jewish icon.

The Argentine-based Yiddish philosophical journal Davke functioned as a mediator between general European philosophy and Jewish philosophy. Its editor Shlomo Suskovich wished to introduce readers of Yiddish to the western tradition of philosophy and, at the same time, to show how Jewish thought contributed to abstract thinking. Through topical issues dedicated to central ideas or to giants among Jewish philosophers, particular knowledge could be successfully transmitted to the reading public.