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Vesicle-Templated Layer-by-Layer Assembly for the Production of Nanocapsules

Hollow structures on the submicrometer scale (urn) are obtained with the assembly of polyelectrolytes according to the layer-by-layer (LbL) technique. Following the LbL procedure, polymers alginate and chitosan were alternatively adsorbed on a vesicular template made of didodecyldimethylammonium bromide (DDAB). Evidence for the removal of the vesicular template entrapped in the alginate/chitosan f

Evaluation of membrane performance and cost estimates during recovery of sodium hydroxide in a hemicellulose extraction process by nanofiltration

The recovery the alkaline solvent from of a residual stream after the extraction of hemicelluloses in wheat bran was investigated. The solution was withdrawn from an ultrafiltration (UF) process in which hemicelluloses were recovered. The UF permeate, containing mainly NaOH, lignin and mono- and oligosaccharides, was treated by nanofiltration (NF). Seven NF membranes were tested in a parametric st

Adsorption of trimethyl phosphate and triethyl phosphate on dry and water pre-covered hematite, maghemite, and goethite nanoparticles

Adsorption of trimethyl phosphate (TMP) and triethyl phosphate (TEP) on well-characterized nanopartides of hematite (alpha-Fe2O3), maghemite (gamma-Fe2O3), and goethite (alpha-FeOOH) has been studied by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), 2D correlation DRIFTS analysis, and X-ray photoelectron spectroscopy (XPS) on dry and water pre-covered surfaces. It is

Dynamics of ionization-induced electron injection in the high density regime of laser wakefield acceleration

The dynamics of ionization-induced electron injection in high density (similar to 1.2 x 10(19) cm(-3)) regime of laser wakefield acceleration is investigated by analyzing the betatron X-ray emission. In such high density operation, the laser normalized vector potential exceeds the injection-thresholds of both ionization-injection and self-injection due to self-focusing. In this regime, direct expe

Secondhand cigarette smoke exposure causes upregulation of cerebrovascular 5-HT(1B) receptors via the Raf/ERK/MAPK pathway in rats.

AIM: Cigarette smoke exposure increases the risk of stroke. Upregulation of 5-hydroxytryptamine 1B (5-HT(1B) ) receptors is associated with the pathogenesis of cerebral ischemia. The present study examined the hypothesis that the expression of 5-HT(1B) receptors is altered in brain vessels after secondhand smoke (SHS) exposure. METHODS: Rats were exposed to SHS in vivo for 200 min daily for 8

Oxidative stress, telomere shortening, and DNA methylation in relation to low-to-moderate occupational exposure to welding fumes.

Evidence suggests that exposure to welding fumes is a risk factor for lung cancer. We examined relationships between low-to-moderate occupational exposure to particles from welding fumes and cancer-related biomarkers for oxidative stress, changes in telomere length, and alterations in DNA methylation. We enrolled 101 welders and 127 controls (all currently nonsmoking men) from southern Sweden. We

Bats coordinate sonar and flight behavior as they forage in open and cluttered environments.

Echolocating bats employ active sensing as they emit sounds and listen to the returning echoes to probe their environment for navigation, obstacle avoidance, and pursuit of prey. The sensing behavior of bats includes the planning of 3D spatial trajectory paths, which are guided by echo information. In this study, we examined the relationship between active sonar sampling and flight motor output as

Equilibrating errors: reliable estimation of information transmission rates in biological systems with spectral analysis-based methods

Shannon's seminal approach to estimating information capacity is widely used to quantify information processing by biological systems. However, the Shannon information theory, which is based on power spectrum estimation, necessarily contains two sources of error: time delay bias error and random error. These errors are particularly important for systems with relatively large time delay values and

On strategic ignorance of environmental harm and social norms

Are people strategically ignorant of the negative externalities their activities cause the environment? Herein we examine if people avoid costless information on those externalities and use ignorance as an excuse to reduce pro-environmental behavior. We develop a theoretical framework in which people feel internal pressure ("guilt") from causing harm-to the environment (e.g., emitting carbon dioxi

Genetic diversity, temporal dynamics, and host specificity in blood parasites of passerines in north China.

Avian blood parasites have been preliminarily studied in East Asia, but no data are available from long-term monitoring. The aim of this study was to evaluate the prevalence, genetic diversity, and temporal dynamics of Plasmodium, Haemoproteus, and Leucocytozoon in two passerine communities (one forest and one urban) in north China from 2008 to 2013, as well as the association between infected lin

Characterization of starch Pickering emulsions for potential applications in topical formulations.

The aim of this work has been to characterize starch based Pickering emulsions as a first step to evaluate their possible use as vehicles for topical drug delivery. A minor phase study of emulsions with high oil content has been performed. Emulsion stability against coalescence over eight weeks and after mild centrifugation treatment has been studied. The particle size, rheological properties and

A Molecular Taxonomy for Urothelial Carcinoma.

PURPOSE: Even though urothelial cancer is the fourth most common tumor type among males, progress in treatment has been scarce. A problem in day-to-day clinical practice is that precise assessment of individual tumors is still fairly uncertain; consequently efforts have been undertaken to complement tumor evaluation with molecular biomarkers. An extension of this approach would be to base tumor c

Variability in diffusion kurtosis imaging: Impact on study design, statistical power and interpretation.

Diffusion kurtosis imaging (DKI) is an emerging technique with the potential to quantify properties of tissue microstructure that may not be observable using diffusion tensor imaging (DTI). In order to help design DKI studies and improve interpretation of DKI results, we employed statistical power analysis to characterize three aspects of variability in four DKI parameters; the mean diffusivity, f

'Because of poverty, we had to come together': collective action for improved food security in rural Kenya and Uganda

Agricultural productivity in East African smallholder systems is notoriously low and food production faces multiple challenges, including soil degradation, decreasing land availability, poor market integration, disease burdens and climate change impacts. However, recent evidence from an in-depth study from two sites in Kenya and Uganda shows signs of new social dynamics as a response to these mult