BACKGROUND Polylactic-co-glycolic acid (PLGA) nanoparticles have been used to increase the relative oral bioavailability of hydrophobic compounds and polyphenols in recent years, but the effects of the molecular weight of PLGA on bioavailability are still unknown. This study investigated the influence of polymer molecular weight on the relative oral bioavailability of curcumin, and explored the...

A gamma ray burst with strong optical-UV emission occuring in a molecular cloud will photodissociate H2, photoionize H2, H, and He, and destroy dust grains. We model these processes, including time-dependent radiative transfer in both continuum radiation and the resonance lines of H2. The UV will pump H2 into vibrationally-excited levels. We calculate the absorption spectrum imprinted on radiat...

Donor-acceptor polymers with an alternating array of donor and acceptor moieties have gained particular attention during recent years as active components of organic electronics. By implementation of suitable subunits within the conjugated backbone, these polymers can be made either electron-deficient or -rich. Additionally, their band gap and light absorption can be precisely tuned for improve...

In vitro studies were performed to investigate a possible mechanism by which lecithin suppresses intestinal cholesterol absorption. The hypothesis that lecithin acts by retarding the diffusion of micelles across the unstirred water layer (UWL) was tested by measuring cholesterol influxes (Ji) in segments of rat intestine under conditions with no maximal and minimal effective thickness of the UW...

We report on the investigation of free-carrier absorption characteristics for epitaxially grown p-type silicon thin films in the far-infrared region ~50–200 mm!, where Si homojunction interfacial workfunction internal photoemission ~HIWIP! detectors are employed. Five Si thin films were grown by molecular beam epitaxy on different silicon substrates over a range of carrier concentrations, and t...

We discuss the detection of absorption by interstellar hydrogen fluoride (HF) along the sight line to the submillimeter continuum sources W49N and W51. We have used Herschel’s HIFI instrument in dual beam switch mode to observe the 1232.4762 GHz J = 1−0 HF transition in the upper sideband of the band 5a receiver. We detected foreground absorption by HF toward both sources over a wide range of v...

The incorporation site of Er dopants inserted at high and low concentration (respectively 5 and 0.5 mol%) in nanoparticles of CaF2 is studied by x-ray absorption spectroscopy (XAS) at the Er L III edge. The experimental data are compared with the results of structural modeling based on density functional theory (DFT). DFT-based molecular dynamics is also used to simulate complete theoretical EX...

A sensitivity comparison was made between conventional atomic absorption spectrophotometry (AAS) and conventional molecular absorption spectrophotometry (MAS) for the serum trace metals, copper, iron, and zinc. The sensitivity aspect considered was absorbances was obtained for concentrations in the solutions analyzed using unit lightpaths of 1 cm and 10 cm for MAS and AAS, respectively. A disti...