Liquid dewetting of ultrathin polystyrene films: Is there a molecular architecture effect?

We have used a liquid dewetting method to investigate the glass transition temperature T_g of high molecular weight linear, long branched 3-arm star, and short branched 8-arm star polystyrene (PS) in the form of ultrathin films. The results of these dewetting experiments are consistent with prior studies of dewetting of linear PS films and show that, independent of molecular architecture, the glass transition temperature T_g reductions with decreasing film thickness, while important below about 20 nm, are weaker than those observed for linear PS supported on a rigid substrate and as well as those observed in freely standing films. The lack of a strong molecular architecture effect on the T_g-reductions is consistent with the T_g reductions for the dewetting from a liquid substrate reflects changes in segmental dynamics upon confinement rather than chain effects. This contrasts with changes, including increases seen in dewetting from a rigid substrate, for different molecular architectures reported in the literature.     

Embedding Quantum Mechanics Into a Broader Noncontextual Theory: A Conciliatory Result

The extended semantic realism (ESR) model embodies the mathematical formalism of standard (Hilbert space) quantum mechanics in a noncontextual framework, reinterpreting quantum probabilities as conditional instead of absolute. We provide here an improved version of this model and show that it predicts that, whenever idealized measurements are performed, a modified Bell-Clauser-Horne-Shimony-Holt (BCHSH) inequality holds if one takes into account all individual systems that are prepared, standard quantum predictions hold if one considers only the individual systems that are detected, and a standard BCHSH inequality holds at a microscopic (purely theoretical) level. These results admit an intuitive explanation in terms of an unconventional kind of unfair sampling and constitute a first example of the unified perspective that can be attained by adopting the ESR model.     

Calibration of the isomer shift of the 14.4?keV transition?of? 57 Fe

With the aim of calibrating Mössbauer spectroscopic measurements, the electron contact density was calculated on the Fe nuclear position in various iron compounds. The full-potential augmented-plane waves plus local orbitals (APW+lo) method within the local-density approximation was used, considering different approximations for the exchange and correlation potential. By comparison with experimental ⁵⁷Fe Mössbauer data, the calibration constant ?? relating measured isomer shifts to the electron contact density was derived. An isomer shift calibration constant ???=???0.25₁ a.u.³ mm s^???1 has been obtained.     

Do Flavonoids from Durum Wheat Contribute to Its Bioactive Properties? A Prospective Study

A clear gap with respect to the potential biological properties of wheat flavonoids exists in the available literature. This information is crucial for breeding programs aiming to produce new varieties presenting improved health benefits. Accordingly, advanced breeding lines of whole durum wheat were evaluated in this contribution. The highest recovery of phenolics was achieved using aqueous acetone (50:50, v/v), as verified by multi-response optimization, thus showing that phenolics could be largely underestimated by employing an inappropriate extraction. The concentration of derivatives of apigenin, the main phenolics present, ranged from 63.5 to 80.7%, as evaluated by LC–ESI-QTOF-MS. Phenolics from the breeding line 98 exhibited the highest ability in scavenging peroxyl radicals, reducing power as well as in terms of inhibition of pancreatic lipase activity, a key enzyme regulating the absorption of triacylglycerols. In contrast, none of the samples exhibited a significant anti-diabetic potential. Despite their high concentration compared to that of phenolic acids, results of this work do not support a significant antioxidant and pancreatic lipase inhibitory effect of durum wheat flavonoids. Therefore, breeding programs and animal and/or human trials related to the effect of durum wheat flavonoids on oxidative stress and absorption of triacylglycerols are discouraged at this point.     

The Effect of Spontaneous Collapses on Neutrino Oscillations

We compute the effect of collapse models on neutrino oscillations. The effect of the collapse is to modify the evolution of the spatial part of the wave function and we will show that this indirectly amounts to a change on the flavor components. For the analysis we use the mass proportional CSL model, and perform the calculation to second order perturbation theory. As we will show, the CSL effect is very small—mainly due to the very small mass of neutrinos—and practically undetectable.     

WILLGERODT-KINDLER'S MICROWAVE-ENHANCED SYNTHESIS OF THIOAMIDE DERIVATIVES

The Willgerodt-Kindlerreaction was applied to a series of aromatic aldehydes and ketones. The reactions were performed in a dipolar aprotic solvent (mainly DMF) in the presence of a base catalyst (4-methylmorpholine) and utilized microwave (mw) irradiation. The pulsed mw technique rather than the continuous irradiation was preferred because it limited side reactions and hydrogen sulfide production. While not always superior to the thermal activation of the reaction, the procedure involving repetitive short pulses of microwave irradiation was found to be faster and result in consistently cleaner products. The technique can be easily applied in a fast parallel synthesis process.