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 of molecular factors from plants pathogen Phytophthora cinnamomi

The culture of the chestnut tree is extremely important in the northern region of Portugal, occupying a significant proportion of useful agricultural area. The annual average chestnut production in Portugal can reach 20 000 tons. New plantation areas have increased in the last few decades. However the ink disease caused by the oomycete Phytophthora cinnamomi has damage and killed many trees and up to now no concrete solutions have been offered to control the illness. As a consequence, the disease propagation in the orchards of chestnut trees has been causing severe productivity and yield breaks. In addition to the economical losses, the importance of sociological and landscape aspects for the region cannot be neglected. Oomycetes species can manipulate biochemical and physiological processes in their host plants through a diverse array of virulence or avirulence molecules, known as effectors. In susceptible plants, these effectors promote infection by suppressing defense responses, enhancing susceptibility, or inducing disease symptoms. Alternatively, in resistant plants, effectors are recognized by the products of plant resistance genes, resulting in host cell death and effective defence responses known as the hypersensitive response (HR). We've identified and characterized some proteins involved in mechanisms of infection by Phytophthora cinnamomi: endo-1,3-beta-glucanase (complete cds), exo-glucanase (partial cds); glucanase inhibitor protein (GIP) (complete cds); necrosis-inducing Phytophthora protein 1 (NPP1) (complete cds) and transglutaminase. Several technologies, such reverse transcriptase PCR, in vivo expression technology, and Bioinformatics tools have been used to study the expression of selected genes from fungi during infection. In this work we intend to integrate the necessary bioinformatics tools that were used in this investigation. These tools include the use of Databases and associated homology programs as Fasta and Clustal, and several programs for sequence analysis and design of experiments such PCR. RT-PCR studies demonstrate that P. cinnamomi elicitins have higher expression in substrates such cellulose and sawdust. The studies of expression of these genes in vivo infection, with cell lines of Castanea sativa, reveal the intimate relationship between plants and phytopathogens has led to the coevolution of a number of complex strategies for attack and defense. For a pathogen to colonize a host successfully, it must develop mechanisms either to evade detection or, failing that, to subvert the defense responses.Sociedade Portuguesa de Microbiologia, Sociedade Portuguesa de BiotecnologiaProjects COMBATINTA/SP2.P11/02 Interreg IIIA – Cross-Border Cooperation Spain-Portugal, financed by The European Regional Development Fund, and “Identification, characterization and role of molecular factors associated with the mechanisms of infection of Fagaceae species by Phytophthora cinnamomi” (PTDC/AGR-AAM/67628/2006) financed by FCT, supported this work

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

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

Automatic structures for semigroup constructions

We survey results concerning automatic structures for semigroup constructions, providing references and describing the corresponding automatic structures. The constructions we consider are: free products, direct products, Rees matrix semigroups, Bruck-Reilly extensions and wreath products.Comment: 22 page

Higher-order variational problems of Herglotz type

We obtain a generalized Euler–Lagrange differential equation and transversality optimality conditions for Herglotz-type higher-order variational problems. Illustrative examples of the new results are given

ANALISIS KEMAMPUAN BERFIKIR ALJABAR DI KELAS VII SMP NEGERI 1 KRANGKENG KABUPATEN INDRAMAYU (Studi Survei di Kelas VII Tahun Akademik 2012/2013)

Setiati Rahayu, 2013. Analisis Kemampuan Berfikir Aljabar di Kelas VII di SMP Negeri 1 Krangkeng Kab. Indramayu (Studi Survei di Kelas VII Tahun Akademik 2012/2013) Untuk mengukur kemampuan berfikir aljabar seorang siswa diperlukan beberapa indikator. Terdapat beberapa indikator untuk memahami aljabar diantaranya memahami pengertian koefisien variabel suku sejenis, kemampuan melakuakan operasi hitung, kemampuan mengggunakan simbol matematika, kemampuan menggunakan bahasa sehari-hari, kemampuan menyederhanakan operasi aljabar, kemampuan menyatakan berbagai hubungan, kemampuan menggunakan diagram alur dan memahami konsep aljabar invers. Tujuan dalam penelitian ini untuk menganalisis kemampuan berfikir aljabar di kelas VII yang ditinjau dari operasi aljabar, penggunaan aljabar, masalah aljabar, dan pemahaman konsep aljabar saat menjawab soal-soal aljabar. Kemampuan siswa dalam memahami aljabar merupakan suatu kondisi yang terdapat dalam sekolah SMP tersebut. Aljabar adalah suatu cabang ilmu matematika yang menggunakan tandatanda dan huruf-huruf yang mewakili angka-angka. Banyaknya indikator yang menjadi indikator kemampuan aljabar, maka akan ada beberapa indikator yang akan menjadi komponen utama dalam kemampuan aljabar. Untuk mengetahui kemampuan siswa dalam memahami aljabar, tidak perlu semua indikator pada\ud materi aljabar diujikan dalam tes. Mengetahui sangat pentingnya komponen utama dalam materi aljabar untuk mengukur kemampuan berfikir aljabar seorang siswa maka peneliti mencoba menganalisis kemampuan berfikir aljabar siswa kelas VII di SMPN 1 Krangkeng. Teknik pengumpulan data yang digunakan dalam penelitian ini adalah tes. Populasi dalam penelitian ini adalah Kelas VII yang berjumlah (160 siswa). Sampel diambil dari kelas VIIB cluster random sampling. Untuk uji coba dilakukan di kelas VIIA yang berjumlah 32. Dari hasil penelitian diperoleh hasil sebagai berikut: 1) Aljabar di SMP N 1 Krangkeng cukup baik hal ini ditunjukan dengan nilai rata-rata 75. 2) Indikator kemampuan berfikir aljabar secara mekanisme dan indikator Kemampuan terbesar yang dicapai oleh siswa kelas VII SMP Negeri 1 Krangkeng tahun ajaran 2012/2013 dalam memahami aljabar adalah pada pengertian koefisien, variabel, konstanta, faktor, suku sejenis adalah sebesar 89.58% dan kemampuan yang kurang dikuasai oleh siswa kelas VII SMP Negeri 1 Krangkeng tahun ajaran 2012/2013 dalam memahami aljabar adalah memahami invers adalah sebesar 85.94%. 3) Dari delapan indicator kemampuan berfikir aljabar ada tiga komponen yang dominan yaitu menggunakan diagram alur, pengertian koefisien variable konstanta, faktor suku sejenis, dan menyederhanakan operasi aljaba

Cosmological effects of scalar-photon couplings: dark energy and varying-α models

We study cosmological models involving scalar fields coupled to radiation and discuss their effect on the redshift evolution of the cosmic microwave background temperature, focusing on links with varying fundamental constants and dynamical dark energy. We quantify how allowing for the coupling of scalar fields to photons, and its important effect on luminosity distances, weakens current and future constraints on cosmological parameters. In particular, for evolving dark energy models, joint constraints on the dark energy equation of state combining BAO radial distance and SN luminosity distance determinations, will be strongly dominated by BAO. Thus, to fully exploit future SN data one must also independently constrain photon number non-conservation arising from the possible coupling of SN photons to the dark energy scalar field. We discuss how observational determinations of the background temper- ature at different redshifts can, in combination with distance measures data, set tight constraints on interactions between scalar fields and photons, thus breaking this degeneracy. We also discuss prospects for future improvements, particularly in the context of Euclid and the E-ELT and show that Euclid can, even on its own, provide useful dark energy constraints while allowing for photon number non-conservation