UNLABELLED PROBLEM/AIMS: Thin sections of impression materials are susceptible to tearing in gingival crevices and interproximal spaces. This study measures the tear strength of six fast and regular set impression materials after different setting times and at different tearing rates. MATERIALS/METHODS Tear strength specimens were prepared of four addition silicone materials: Aquasil (Dentspl...

Intracranial pressure and volume vary considerably between hydrocephalic patients, and with age, health and haemodynamic status; if left untreated, intracranial pressure rises and the ventricular system expands to accommodate the excess cerebrospinal fluid, with significant morbidity and mortality. Cerebrospinal fluid shunts in use today have a high incidence of failure with shunt obstruction b...

AIMS To investigate the effect of the storage period on the accuracy of recently developed elastomeric materials. METHODS Simultaneous impressions of a steel die were taken using a polyether (I: Impregum Soft Heavy and Light body, 3M ESPE) and vinyl polysiloxane (P: Perfectim Blue Velvet and Flexi-Velvet, J.Morita). The trays were loaded with the heavy-bodied impression materials while the li...

The viscoelastic properties of nine silicone-, polysulfide-, and polyether-based impression materials were determined using creep tests. During deformation the materials demonstrated linear viscoelastic behavior. The creep compliance curves, recovery, and percent set were calculated. Permanent deformation in these materials is a result of lack of recovery of elastic deformation as well as visco...

The complete absolute configuration of goniodomin A, an actin-targeting polyether macrolide isolated from the marine dinoflagellate Alexandrium hiranoi, was established from analysis of ROESY experiments and coupling constants, synthesis of suitable model compounds for NMR spectroscopic comparisons, degradation experiments, and correlation with synthetic reference compounds.

Glycodendrons are multivalent glycoconjugates bearing an orthogonal functional group at the focal point of the molecule. This allows for their postsynthetic elaboration to achieve amphiphilic glycolipid mimetics, for example, which eventually can be applied in biology, biophysics, or material science. Here, postsynthetic modification of di- and tetravalent polyether glycodendrons has been explo...

Highly crystalline rutile with a specific surface area as high as 280 m(2) g(-1) and well-connected uniform mesoporosity has been synthesized by rigid templating using commercial, low-cost polyether block amide. This general, simple synthesis route for high surface-area mesoporous nanocrystalline oxides and nanocomposite membranes is important for catalysis, sensors, energy storage, solar cells...

The polyether antibiotics reported by the year 1968 were nigericin1) (X-4642)), lasalocid (X-537A2)), X-2062), dianemycin3) and monensin4). Monensin (1) was the only one whose structure was known at that time. In the following decade, the number of distinct polyethers increased from these five to forty-six, almost all of which were structurally assigned. As a result of this rapid growth, a numb...