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Infection prevention in electrophysiology (EP) laboratories is poorly characterized; thus, we conducted a cross-sectional survey using the SHEA Research Network. We found limited uptake of basic interventions, such as surveillance and appropriate peri-procedural antimicrobial use. Further study is needed to identify ways to improve infection prevention in this setting.
Necrotising external otitis, also known as malignant otitis externa, is an aggressive, resorptive osteomyelitis of the temporal bone. Although rare, necrotising external otitis is a potentially fatal disease, with complications which include temporomandibular joint osteomyelitis, sigmoid sinus thrombosis and meningitis. Imaging findings may be subtle, particularly in the early stages. We present a broad range of imaging findings which may occur in necrotising external otitis cases.
Nanometer-scale iron oxide magnetic particles have been formed in the porous network of a cross-linked polymer matrix by ion exchange and subsequent hydrolysis. The oxide particles are uniform, well-dispersed and spherical with a diameter ranging between 30 and 1200 Å depending on the synthesis conditions. The DC magnetic susceptibility, measured between 4 and 300 K, continuously increases with decreasing temperature and tends to saturate at low temperatures. Composites containing iron oxide particles with an average diameter of 80 Å exhibit superparamagnetism while those on the order of 1000 Å undergo an antiferromagnetic-type transition at 33 K. The magnetic susceptibility is critically dependent upon the particle size and the strength of the magnetic field.
Nanometer size lead iodide particles have been synthesized in the porous network of a cross-linked polymer matrix. The optical band gap of the nanocrystals is shifted towards higher energy as compared to the bulk value. This shift is attributed to the quantum size effect on excitons. Intercalation with aniline leads to a further shift in the band gap which depends on the dipole moment of the intercalated guest species. Differential scanning calorimetry and high temperature x-ray diffraction have been used to analyze the ferroelectric transition in Pbl2.
A new generation of substrate materials with low dielectric permittivity have been developed. These new ceramic-based nanocomposites consist of a quasi two-dimensional, multilayered structure realized by the intercalation of molecular species into the galleries of a host lattice. The materials have been characterized by x-ray diffraction, electronic and infrared spectroscopy. The relative permittivities vary between 2.5 and 4 at 1 MHz. The new hybrids can be processed at relatively low temperatures (below 350°C) and allow for step coverage of submicron structures.
Artificial membranes possessing physicochemical properties similar to biological membranes have been synthesized by immobilization of synthetic amphiphiles in layered ceramics. The intercalated bilayer-forming amphiphiles exhibit a gallery height of about 39 Å. Retention of bilayer-forming characteristics is further confirmed by the presence of a crystal to liquid-crystal phase transition. A dramatic increase in the membrane capacitance at the tansition temperature is attributed to an increase in membrane fluidity.
Schizophrenia has been associated with limited abilities to interact effectively in social situations. Face perception and ability to recognise familiar faces are critical for social interaction. Patients with chronic schizophrenia are known to show impaired face recognition. Studying first-episode (FE) patients allows the exclusion of confounding effects of chronicity, medication and institutionalisation in this deficit.
To determine brain (dys)functions during a face encoding and recognition paradigm in FE schizophrenia.
Thirteen antipsychotic-naïve FE schizophrenia patients and 13 age- and sex-matched healthy controls underwent functional magnetic resonance imaging during a face encoding and recognition paradigm. Behavioural responses were recorded on line.
Patients recognised significantly fewer of previously presented faces than the controls (p = 0.008). At the neural level, both groups activated a network of regions including the fusiform area, occipital, temporal and frontal regions. In brain activity, the two groups did not differ in any region during encoding or recognition conditions (p > 0.05, corrected or uncorrected).
Our findings show impaired face recognition without a significant alteration of related brain activity in FE schizophrenia patients. It is possible that neural changes become more strongly evident with progression of the illness, and manifest themselves as behavioural impairments during the early course.
Ba0.75Sr0.25TiO3 thin films have been deposited on single-crystal MgO substrates by pulsed laser deposition with the objective of forming ferroelectric films with a low Curie temperature. The films have been characterized by capacitance measurements and by transmission electron microscopy, x-ray diffraction, and Rutherford backscattering spectrometry (random and channeled). Films deposited with the substrate at 500 °C are polycrystalline, while those deposited at 650 °C are highly aligned and possibly epitaxial. The films are transparent in the visible region with an optical absorption edge at about 300 nm. Capacitance measurements on the polycrystalline films reveal a Curie transition at 283 K. The lowering of Curie temperature from the corresponding bulk sample is attributed to the films being under compression, as verified by Raman spectroscopy.
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