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Psychiatric symptoms associated with frontal lobe unruptured or ruptured intracranial dermoid cysts are rarely described in the medical literature. The case of a 58-year-old man with a chronic history of anxiety, major depression, and obsessive compulsive disorder who presented with new onset auditory and visual phenomena is described. This case illustrates the need to include an underlying brain tumor in the differential diagnosis when encountering new onset auditory and visual phenomena in patients with chronic mood and/or anxiety disorders.

This work represents the nature of conduction mechanism in bismuth silicate (BiSiO) nanofibers as a function of temperature and frequency. Scanning electron micrographs and X-rays diffraction patterns exhibited the formation of cubic phases of Bi 4 (Sio 4 ) 3 and Bi 12 Sio 20 nanofibers respectively with an average diameter of ~200 nm. Temperature dependent (300 K-400 K) electrical characterization of fibers was carried out in frequency range of ~20 Hz-2 MHz. The complex impedance analysis showed contribution from bulk and intergranular parts of nanofibers in conduction. Moreover, analysis of the Cole-Cole plot confirmed the space charge dependent behavior of BiSiO nanofibers. Two types of relaxation phenomena were observed through Modulus analysis. In ac conductivity curve, step like feature of plateau and dispersive regions were described by Maxwell-Wagner effect while the dc part obeyed the Arrhenius law. However, frequency dependent ac conductivity revealed the presence of conduction mechanism in diverse regions that was ascribed to large polaron tunneling model. Detailed analysis of complex Impedance and ac conductivity measurement showed negative temperature coefficient of resistance for the BiSiO nanofibers. Current-voltage (IV) characteristics represented ohmic conduction; followed by space charge limited current conduction at intermediate voltages. Results from both ac and dc measurements were in good agreement with each other.

The Mössbauer effect has been used to study the effect of varying the Fe to Ni ratio in the compounds Dy(Fe1−xNix)3 and Y(Fe1−xNix)3 on the Fe57 hyperfine field and the ordering temperature. The results are compared with other recent studies and related compounds.