Near-field scanning optical microscopy and single-molecule spectroscopy have been employed to study a large number of blends containing a highly fluorescent and amorphous conjugated polymer, ‘superyellow’ (a phenylenevinylene copolymer). We find that blend films with a nonfluorescent and semi-crystalline polymer, poly(ethylene oxide) (PEO), with a superyellow content between 9 and 50 mass% exhi...

Tubeless and open siphons operate without conduits, in the open, supported only by extensional stresses. Here, we demonstrate that the addition of silica nanoparticles in modest concentrations (on the order of 1% by weight) to an aqueous Poly(ethylene oxide) (PEO) solution of a moderately low concentration (0.5% by weight) has a dramatic effect on the power of the siphon as well as on the abili...

Aqueous suspensions of mixtures of the rodlike virus tobacco mosaic virus (TMV) with globular macromolecules such as polyethylene oxide (PEO) or bovine serum albumin (BSA) phase separate and exhibit rich and strikingly similar phase behavior. Isotropic, nematic, lamellar, and crystalline phases are observed as a function of the concentration of the constituents and ionic strength. The observed ...

A comparative investigation of the aggregation in aqueous solution of a poly(ethylene oxide)-poly(propylene oxide)poly(ethylene oxide) block copolymer (PEO-PPO-PPO) (Pluronic F127) with a polydimethylsiloxane-graft-polyether (PDMS-PEO) has been done. The spectroscopic parameters obtained from absorption spectra of the 4,4,5,5tetramethylimidazoline-1-oxyl-3-oxide-2-undecyl (TEMIDO-undecyl) and f...

The present work focused on the preparation and morphological characterization of chitosan-based nanofiber membranes, aiming at applications in medical and pharmacological areas. Membranes with nanofiber diameters ranging from 50 – 300 nm were prepared from polymer solutions through the electrospinning process. To stabilize the process, it was necessary to use poly(ethylene oxide) (PEO), which ...

The structural evolution of low-molecular-weight poly(ethylene oxide)-block-polystyrene (PEO-b-PS) diblock copolymer thin film with various initial film thicknesses on silicon substrate under thermal annealing was investigated by atomic force microscopy, optical microscopy, and contact angle measurement. At film thickness below half of the interlamellar spacing of the diblock copolymer (6.2 nm)...

Contrary to common belief, back pain amongst young people is a frequent phenomenon. Epidemiological studies have found high prevalence rates of back pain amongst schoolchildren. The investigation reported here aims to validate children's self-reporting and the observation of sitting postures to establish the intensity, duration and frequency of exposure in the classroom. The sitting postures of...

The effect of ligand structure on the magnetic resonance (MR) imaging and biodistribution of six gadolinium (Gd) chelates based on a hydroxypyridonate-terephthalimide (HOPO-TAM) ligand design was investigated. Modifications to the molecular structure of the Gd-HOPO-TAM chelates (hydrophilicity and aromatic group substitution) significantly influence the efficacy of imaging and biodistribution. ...

Aim of this study was to evaluate in patients with progressive external ophthalmoplegia (PEO) the left ventricular function by standard echocardiography and tissue Doppler imaging (TDI) analysis. Twenty patients with PEO (55.4 ± 17.5 years) and 20 ageand sex-matched healthy subjects underwent standard echocardiography with TDI analysis to assess left ventricular function. TDI was performed by p...