264 research outputs found
Role of shore platforms on coastal cliffs protection in Algarve (South Portugal): first approach
The complex interaction between morphogenetic processes acting on rocky coasts and substrate characteristics
difficult the assessment of its evolution at different time scales. In opposition to other coastal environments such
as beaches, where variations on substrateâs attributes are constrained to a few possibilities, rocky coasts expose
substrates having large amount of variables, among them, lithology, mechanical and chemical strength, density
and orientation of faults and joints and, rocksâ texture and structure (e.g., Trenhaile, 2003).Portuguese Foundation for Science and Technology-FC
Observation of Replica Symmetry Breaking in the 1D Anderson Localization Regime in an Erbium-Doped Random Fiber Laser
The analogue of the paramagnetic to spin-glass phase transition in disordered
magnetic systems, leading to the phenomenon of replica symmetry breaking, has
been recently demonstrated in a two-dimensional random laser consisting of an
organic-based amorphous solid-state thin film. We report here the first
demonstration of replica symmetry breaking in a one-dimensional photonic system
consisting of an erbium-doped random fiber laser operating in the
continuous-wave regime based on a unique random fiber grating system, which
plays the role of the random scatterers and operates in the Anderson
localization regime. The clear transition from a photonic paramagnetic to a
photonic spin glass phase, characterized by the probability distribution
function of the Parisi overlap, was verified and characterized. In this unique
system, the radiation field interacts only with the gain medium, and the fiber
grating, which provides the disordered feedback mechanism, does not interfere
with the pump
Characterization of Acrocarpus fraxinifolius wood submitted to heat treatment
Aiming to provide greater visibility for the wood species Acrocarpus fraxinifolius, the present study sought to analyze the influence of heat treatment on an industrial scale applied to wood species, also popularly known as Indian cedar. The heat treatment was carried out in an autoclave, with temperature and pressure control, and with saturated steam injection, for temperatures 155 ÂșC, 165 ÂșC, 175 ÂșC, and 185 ÂșC. Physical, chemical, and mechanical tests were carried out for the analyzed wood. The content of holocellulose and total lignin decreased, while the content of extractives showed a substantial increase. The density increased after the heat treatment, however the treated wood showed cracks, and these cracks influenced the significant loss of the values of the mechanical properties of compression, tension, and flexion. The shear showed strength gain for the temperature of 155 ÂșC, and the wood treated at 165 ÂșC was equivalent to untreated wood. The woods submitted to temperatures of 175 ÂșC and 185 ÂșC presented strength losses. The heat treatment in question contributes to increase the visibility, use and market value of wood
Environmental Assessment for Ocean Energy Schemes: Useful Tools and Case Studies
This work concerns a review of the state of the art of current and practical experience on environmental assessment (including monitoring) in order to set the path to be followed for future ocean energy schemes. It includes a revision of the work done so far in some test sites and deployment sites and discusses the use of several tools considering project phases (installation, deployment and decommissioning) and environmental impact assessment steps (screening, scoping, baseline studies for reference condition characterization, impact identification and evaluation, mitigation measures and monitoring). Within the list of such tools the applicability of checklists, matrices, mathematical modelling, Geographic Information Systems are considered as well as other shared and integrative methods: Environmental Risk Assessment and Life Cycle Analysis
AnĂĄlise da AderĂȘncia das PrĂĄticas Recomendadas pelos MĂ©todos Ăgeis: XP, Scrum e TDD com a Utilização de Ferramentas CASE
Este artigo especifica uma métrica para avaliar o nível de aderência das funcionalidades oferecidas pelas ferramentas CASE Scrum-Half, JUnit, Netbeans e Eclipse, com as principais práticas recomendadas pelas metodologias ágeis no desenvolvimento de aplicações. Para tanto, este trabalho adota um critério de aferição, no qual cada prática avaliada recebe um peso de acordo com o grau de evidências encontrado, e assim, por meio de uma expressão aritmética é possível determinar a aderência de cada prática em relação às ferramentas CASE investigadas. Como contribuição, descreve-se como uma equipe de desenvolvimento pode executar as práticas recomendadas pelos métodos ágeis no desenvolvimento de aplicações com o auxílio da ferramenta CASE mais adequada
AnĂĄlise da AderĂȘncia das PrĂĄticas Recomendadas pelos MĂ©todos Ăgeis: XP, Scrum e TDD com a Utilização de Ferramentas CASE
Este artigo especifica uma mĂ©trica para avaliar o nĂvel de aderĂȘncia das funcionalidades oferecidas pelas ferramentas CASE Scrum-Half, JUnit, Netbeans e Eclipse, com as principais prĂĄticas recomendadas pelas metodologias ĂĄgeis no desenvolvimento de aplicaçÔes. Para tanto, este trabalho adota um critĂ©rio de aferição, no qual cada prĂĄtica avaliada recebe um peso de acordo com o grau de evidĂȘncias encontrado, e assim, por meio de uma expressĂŁo aritmĂ©tica Ă© possĂvel determinar a aderĂȘncia de cada prĂĄtica em relação Ă s ferramentas CASE investigadas. Como contribuição, descreve-se como uma equipe de desenvolvimento pode executar as prĂĄticas recomendadas pelos mĂ©todos ĂĄgeis no desenvolvimento de aplicaçÔes com o auxĂlio da ferramenta CASE mais adequada
Development of an inhalational therapeutical system based on bacteriophages to treat pharyngo-tonsillitis : a nanoencapsulation approach
Inflammatory diseases that occur in the pharynx and involving both the adenoids and tonsils are important
not only for being very frequent, but also because they often require minor surgery for their resolution. These
structures have immunological functions leading to production of antibodies, and work in the local immunity
of the pharynx and protection of the entire body. The most common etiologic agent of sore throats is
Streptococcus pyogenes, an important pathogen of the beta-hemolytic group A which causes streptococcal
pharyngitis. The emergence of antibiotic-resistant bacterial strains and the poor penetration of chemical
antibiotics in bacterial biofilms raise the need for safe and effective options of antimicrobial treatment. The
application of bacteriophages (or cocktails therefrom) has been proposed as an alternative (or complement)
to conventional chemical antibiotics, allowing the release of natural predators of bacteria directly on these
biofilms. The major advantage of bacteriophage-based antibiotherapy relative to its conventional chemical
counterpart is that bacteriophages replicate at the site of infection, being available in abundance where they
are needed the most. When compared with chemical antibiotics, bacteriophages have other important
advantages: (i) strong tissue permeability, (ii) bacteriophage concentration remains high at the focus of
infection, continuously increasing with bacterial (host) presence, (iii) elimination of the focus of infection
occurs only after eradication of the host bacterium, (iv) bacteriophages are fully compatible with antibiotics
and may act synergistically, (v) they are specific against the target bacteria, (vi) have a superior ability to
penetrate bacterial biofilms, inducing production of enzymes that hydrolyze the biofilm polymeric matrix, (vii)
although bacteria can develop resistance to bacteriophages, isolation of new lytic bacteriophages is much
simpler and cheaper than developing a new chemical antibiotic. In this research effort, development of a
biotechnological process for the inhalational administration of a bacteriophage cocktail (endotoxin free) was
pursued, using strategies of nanoencapsulation within lipid nanovesicles (as forms of protection for the
bacteriophage against the immune system) to treat infectious pathologies such as pharyngo-tonsillitis
caused by Streptococcus pyogenes. This method of targeting may have a high potential for the treatment of
bacterial infections of the respiratory tract, since inhalation therapy is considered to be favorable to certain
respiratory infections because the aerosol is delivered directly at the site of infection, accelerating the action
of bacterial predators. Additionally, a smaller amount of bioactive substance is needed, thus preventing or
reducing possible side effects. As a proof of concept for the nanoencapsulation strategy, and since there is
not yet available a strictly lytic bacteriophage cocktail for Streptococcus pyogenes, a well-defined and
characterized bacteriophage was utilized, viz. bacteriophage T4. Water-in-oil-in-water (W/O/W) multiple
emulsions are nanosystems in which dispersions of small water droplets within larger oil droplets are
themselves dispersed in a continuous aqueous phase. Due to their compartimentalized internal structure,
multiple emulsions present important advantages over simple O/W emulsions for encapsulation of
biomolecules, such as the ability to carry both polar and non-polar molecules, and a better control over
releasing of therapeutic molecules. T4 bacteriophage was entrapped within W/O/W multiple nanoemulsions,
aiming at mimicking the multifunctional design of biology, optimized with several lipid matrices, poloxamers
and stabilizing layer compositions. Physicochemical characterization of the optimized bacteriophageencasing
nanovesicle formulations encompassed determination of particle size, size distribution and particle
charge, via Zeta potential analysis, surface morphology via CRYO-SEM, and thermal analysis via DSC
Semicircular canal size constrains vestibular function in miniaturized frogs
Miniaturization has evolved repeatedly in frogs in the moist leaf litter environments of rainforests worldwide. Miniaturized frogs are among the worldâs smallest vertebrates and exhibit an array of enigmatic features. One area where miniaturization has predictable consequences is the vestibular system, which acts as a gyroscope, providing sensory information about movement and orientation. We investigated the vestibular system of pumpkin toadlets, Brachycephalus (Anura: Brachycephalidae), a clade of miniaturized frogs from Brazil. The semicircular canals of miniaturized frogs are the smallest recorded for adult vertebrates, resulting in low sensitivity to angular acceleration due to insufficient displacement of endolymph. This translates into a lack of postural control during jumping in Brachycephalus and represents a physical constraint resulting from Poiseuilleâs law, which governs movement of fluids within tubes
A Formalization of the Theorem of Existence of First-Order Most General Unifiers
This work presents a formalization of the theorem of existence of most
general unifiers in first-order signatures in the higher-order proof assistant
PVS. The distinguishing feature of this formalization is that it remains close
to the textbook proofs that are based on proving the correctness of the
well-known Robinson's first-order unification algorithm. The formalization was
applied inside a PVS development for term rewriting systems that provides a
complete formalization of the Knuth-Bendix Critical Pair theorem, among other
relevant theorems of the theory of rewriting. In addition, the formalization
methodology has been proved of practical use in order to verify the correctness
of unification algorithms in the style of the original Robinson's unification
algorithm.Comment: In Proceedings LSFA 2011, arXiv:1203.542
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