Highly confined epsilon-near-zero and surface phonon polaritons in SrTiO membranes.

Recent theoretical studies have suggested that transition metal perovskite oxide membranes can enable surface phonon polaritons in the infrared range with low loss and much stronger subwavelength confinement than bulk crystals. Such modes, however, have not been experimentally observed so far. Here, using a combination of far-field Fourier-transform infrared (FTIR) spectroscopy and near-field synchrotron infrared nanospectroscopy (SINS) imaging, we study the phonon polaritons in a 100 nm thick freestanding crystalline membrane of SrTiO transferred on metallic and dielectric substrates.

Thermal and electrostatic tuning of surface phonon-polaritons in LaAlO/SrTiO heterostructures.

Phonon polaritons are promising for infrared applications due to a strong light-matter coupling and subwavelength energy confinement they offer. Yet, the spectral narrowness of the phonon bands and difficulty to tune the phonon polariton properties hinder further progress in this field. SrTiO - a prototype perovskite oxide - has recently attracted attention due to two prominent far-infrared phonon polaritons bands, albeit without any tuning reported so far.

Bulk and Nanocrystalline Cesium Lead-Halide Perovskites as Seen by Halide Magnetic Resonance.

Lead-halide perovskites increasingly mesmerize researchers because they exhibit a high degree of structural defects and dynamics yet nonetheless offer an outstanding (opto)electronic performance on par with the best examples of structurally stable and defect-free semiconductors. This highly unusual feature necessitates the adoption of an experimental and theoretical mindset and the reexamination of techniques that may be uniquely suited to understand these materials. Surprisingly, the suite of methods for the structural characterization of these materials does not commonly include nuclear magnetic resonance (NMR) spectroscopy.

Impact of information technology on information gaps in canadian ambulatory care encounters.

Background: Specialist physicians require clinical information for patient visits in ambulatory encounters, some of which they may access via digital health solutions.

Objective: This study explored the completeness of information for patient care and the consequences of gaps for ambulatory specialist services provided in ambulatory settings in Canada.

Methods: A sample of specialist physicians practising in outpatient clinics was recruited from a health care provider research panel.

Regional variations in self-protection in Canada.

We use the Canadian General Social Surveys of 1999 and 2004 on victimization to examine regional variations in self-protection. Analyses based on 49,624 respondents reveal that residents of Western Canada--the Prairies and British Columbia--are more likely to own guns for protection, controlling for different measures of victimization, insecurity, and urbanization. Residents from British Columbia are also more likely to practice martial arts.

Chemical information media in the chemistry lecture hall: a comparative assessment of two online encyclopedias.

The chemistry encyclopedia Römpp Online and the German universal encyclopedia Wikipedia were assessed by first-year university students on the basis of a set of 30 articles about chemical thermodynamics. Criteria with regard to both content and form were applied in the comparison; 619 ratings (48% participation rate) were returned. While both encyclopedias obtained very good marks and performed nearly equally with regard to their accuracy, the average overall mark for Wikipedia was better than for Römpp Online, which obtained lower marks with regard to completeness and length.

Influence of physicochemical and biological parameters on drug release from microspheres adhered on vesical and intestinal mucosa.

The object of our work is to develop mucoadhesive microspheres to be applied into the urinary bladder. In the present study the microspheres were prepared and the release of a model drug after their adhesion to mucosa was evaluated. The microspheres were prepared by solvent evaporation method using Eudragit RL or hydroxypropylcellulose as matrix polymers and one out of five different polymers as mucoadhesives or non-mucoadhesive references.