Microencapsulation by coacervation of biodegradable polymer with thyme oil

The objective of this work is to develop a novel coacervation process to produce microcapsules of PLA to encapsulate thyme oil that will be used in cosmetics. PLA is soluble in organic solvents but insoluble in water. Generally, PLA is used to encapsulate water soluble active principles such as drugs, pesticides and dye-stuffs by coacervation, mainly by means of microspheres production or by using double emulsion techniques (o/w/o). However, the objective of this work is to encapsulate thyme oil, a water insoluble active principle that needs, in a first step, the preparation of an oil-in-water emulsion. The novelty of our process consists on dissolving PLA in dimethylformamide (DMF) which is a good solvent for PLA but in addition has high solubility in water. Upon contact with water, the homogeneous solution of PLA in DMF, promotes the precipitation of PLA around the thyme oil core. With this work we demonstrate a new, easy and executable method of coacervation by introducing modifications on microencapsulation process that allow the encapsulation of an oily active principle by simply preparing an o/w emulsion. Control of size and wall thickness of microcapsules, encapsulation efficiency, the influence of surfactants and release of thyme oil were studied. The produced microcapsules have bimodal particle size distributions in volume with a mean particle size of 40 μm. Microcapsules analysis by microscopy have confirmed the spherical shape, the rough surface, and allowed the estimation of the wall thickness around 5 μm. Quantification of the encapsulated thyme oil was performed by gas chromatography and allowed to evaluate the quality of the encapsulated oil and pointed out for a preferential encapsulation of thyme oil apolar compounds.FCT: Grant SFRH/BD/43215/2008

Microencapsulation of thyme oil by coacervation

In this work we have developed a process to encapsulate thyme oil using PLA as the wall material. Firstly, an oil-in-water (o/w) emulsion stabilized with tween 20 (HLB of 16,7) and a solution of PLA in dimethylformamide (DMF) have been prepared. Thereafter, the PLA solution was added to the previously prepared o/w emulsion. The o/w emulsion was obtained by dispersion with an ultraturrax and the encapsulation process proceeded under stirring using an impeller stirrer in a batch actor. The microcapsules formed were hardened by adding octamethylcyclotetrasiloxane and allowed to stand during one hour. After this step, they were decanted and washed with pluronicÒ F68 solution (0.1% w/w), an ethanol solution (30% v/v), and hexane. Finally, the microcapsules were freeze-dried during 24h

Characterization and evaluation of commercial fragrance microcapsules for textile application

In this paper, some commercial microcapsule samples, containing different fragrances used for textile application purposes, were characterized and evaluated. Microcapsule samples were evaluated in terms of particle size, morphology, shell material composition, and fragrance intensity. The effectiveness of the textile impregnation and its durability were assessed. The selection of samples used in each study was made in order to the specific goals of characterization and evaluation of microcapsules. Lemon_Bayer, Lemon_Focor, Lemon_Horquim, Strawberry_Horquim, and Jasmine_Focor samples were used to study the morphology and particle size distribution, and it was observed that microcapsules have a spherical shape with size between 2 and 6 lm. The chemical composition of Lavender_Horquim, Mints_Horquim, Eucaliptus_Focor, and Apple_Focor samples was checked/ confirmed and was based on melamine copolymers including melamine-formaldehyde ones. Lemon_Horquim microcapsules were impregnated on textile substrates, and it was observed that a loss of 46% of limonene occurred after one domestic wash and a loss of 97% occurred after 20 domestic washes

Synthesis of polyurethane-urea microcapsules with perfume for textile application

This work is a contribution to the introduction of emergent technologies in the textile sector, namely the microencapsulation of fragrances and its application to obtain added-value products. Polyurethane/urea microcapsules with a perfume have been produced using the interfacial polymerization technology for industrial application on textile substrate having in view man suits production. The specific objective of this work is the production of a scented clothing line, which includes: Development of technologies/processes for the production of microcapsules; Incorporation of microcapsules into textile substrates and optimization of the process in a laboratory; Validation and industrial scale-up; Development of testing methods and analysis of the release of the perfume.SCENTFASHION, contract ADI/2004/M2.3/0015POC

Occurrence and exposure of 3-monochloropropanediol diesters in edible oils and oil-based foodstuffs from the Spanish market

During the industrial refining process of edible oils and the manufacture of oil-based foodstuff, contaminants such as 3-monochloropropanediol (3-MCPD) fatty acid diesters can be produced. One hundred samples of different edible oils and related fatty food purchased from local Spanish markets were analyzed to evaluate the occurrence of these contaminants. Data of seven 3-MCPD diesters together with corresponding total 3-MCPD equivalents are presented. The procedure is based on a modified QuEChERS protocol followed by LC-MS/MS analysis. Extra virgin olive oil (EVOO) and unrefined oils did not contain detectable levels of the target analytes. The highest levels of 3-MCPD diesters were found in palm oils, for 1,2-Dilinoleoyl-3-chloropropanediol (LILI) and 1–2-Bispalmitoyl-3-chloropropanediol (PAPA) with concentrations close to 10 mg kg−1 and in the lipid fraction of margarines (8.09, 3.77 and 3.72 mg kg−1 for LILI, PAPA and 1-Oleoyl-2-linoleoyl-3-chloropropanediol (OLLI), respectively).Spanish Ministry of Science and Innovation (Project AGL-2014-53647-R) and FEDER fund

ERP correlates of error processing during performance on the HalsteadCategory Test

The Halstead Category Test (HCT) is a neuropsychological test that measures a person's ability to formulate and apply abstract principles. Performance must be adjusted based on feedback after each trial and errors are common until the underlying rules are discovered. Event-related potential (ERP) studies associated with the HCT are lacking. This paper demonstrates the use of amethodology inspired on Singular SpectrumAnalysis (SSA) applied to EEG signals, to remove high amplitude ocular andmovement artifacts during performance on the test. This filtering technique introduces no phase or latency distortions, with minimum loss of relevant EEG information. Importantly, the test was applied in its original clinical format, without introducing adaptations to ERP recordings. After signal treatment, the feedback-related negativity (FRN) wave, which is related to error-processing, was identified. This component peaked around 250ms, after feedback, in fronto-central electrodes. As expected, errors elicited more negative amplitudes than correct responses. Results are discussed in terms of the increased clinical potential that coupling ERP informationwith behavioral performance data can bring to the specificity of theHCT in diagnosing different types of impairment in frontal brain function.info:eu-repo/semantics/publishedVersio

Superluminal Localized Solutions to Maxwell Equations propagating along a waveguide: The finite-energy case

In a previous paper of ours [Phys. Rev. E64 (2001) 066603, e-print physics/0001039] we have shown localized (non-evanescent) solutions to Maxwell equations to exist, which propagate without distortion with Superluminal speed along normal-sized waveguides, and consist in trains of "X-shaped" beams. Those solutions possessed therefore infinite energy. In this note we show how to obtain, by contrast, finite-energy solutions, with the same localization and Superluminality properties. [PACS nos.: 41.20.Jb; 03.50.De; 03.30.+p; 84.40.Az; 42.82.Et. Keywords: Wave-guides; Localized solutions to Maxwell equations; Superluminal waves; Bessel beams; Limited-dispersion beams; Finite-energy waves; Electromagnetic wavelets; X-shaped waves; Evanescent waves; Electromagnetism; Microwaves; Optics; Special relativity; Localized acoustic waves; Seismic waves; Mechanical waves; Elastic waves; Guided gravitational waves.]Comment: plain LaTeX file (12 pages), plus 10 figure

Análise Espacial Da Produtividade De Serapilheira Em Uma Mata De Galeria

The gallery forests have great genetic diversity and important ecological functions, such as protecting the headwaters, controlling erosion, and functioning as buffer zones and filtering chemicals. Litterfall, which can be used as an indicator of ecological productivity, is widely collected using litter traps that are randomly distributed in a forest plot. However, vegetation distribution may present spatial dependence, thus the yield of the litterfall can be mapped using geostatistical techniques allowing the delineation of management zones. Therefore, the objective of this study was to evaluate the efficiency of geostatistical methods using the zoning management productivity of litterfall on a gallery forest in central Brazil. The study was conducted on the gallery forest along the ‘Lava-pés’ stream in Goiás State, Brazil where the experimental site (3 ha) was structured in a grid of 60 litterfall traps, each of 0.33 m2 held 0.65 m above the ground, georeferenced, spaced at 32 x 32 m intervals. Litterfall was monthly collected from December 2011 to November 2012. All litterfall samples were manually separated into three fractions: leaves (LE), branch bark (BB), and reproductive parts (RP) and they were expressed in kg ha-1. Statistical analyses consisted of data description and geostatistics. The litterfall of for LE and total showed strong spatial dependence. The BB and RP showed pure nugget effect. The total litterfall maps obtained by the Kriging interpolation method indicated zones in the map ranging from 900 to 10,900 kg ha-1 per yr. The kriging interpolation technique delineate management zones of productivity in the gallery forest litterfall studied, which allowed the specific forest management of litterfall. © 2016, Universidade Federal de Santa Maria. All Rights Reserved.26248950

Reconstruction of field theory from excitation spectra of defects

We show how to reconstruct a field theory from the spectrum of bound states on a topological defect. We apply our recipe to the case of kinks in 1+1 dimensions with one or two bound states. Our recipe successfully yields the sine-Gordon and $\lambda \phi^4$ field theories when suitable bound state spectra are assumed. The recipe can also be used to globally reconstruct the inflaton potential of inflationary cosmology if the inflaton produces a topological defect. We discuss how defects can provide ``smoking gun'' evidence for a class of inflationary models.Comment: 10 pages, 4 figures. Included proof (Appendix B) that wall fluctuation potentials have supersymmetric form. Added reference

Potential for macro and micronutrients extraction from tomato plants with different soil water stresses

Different tomato cultivars may present differentiated water needs, making it indispensable to study water demand. Thus, the objective of this work was to evaluate the influence of six water stresses in the soil on the extraction potential of macro and micronutrients in the aerial part of tomato in vegetative stage, cultivar ‘Dominador’ F1, under protected cultivation and drip. The experiment was installed in a greenhouse with a randomized block design with four replications. The treatments consisted of six soil water stresses as indicative of the time of irrigation. The preset stresses were 20, 45, 70, 95, 120 and 145 kPa at 20 cm depth. At 140 days after transplanting, the variables evaluated were: the macro and micronutrient content of shoots. The results showed that to obtain higher levels of macro (P and S) and micronutrients (B and Cu) of the total aerial part of the ‘Dominador’ tomato plant F1, it was obtained at a voltage of 20 kPa, and its value was reduced linearly with the increase of the water tension in the soil