62 research outputs found
Road network design with space syntax in Vendas Novas
The city of Vendas Novas, Évora, Portugal, is crossed by a national road. Currently, 30.000 to 35.000 vehicles cross the city, of which more than 2.000 are heavy motor vehicles. Due to the negative effects of the high levels of traffic, the city council as long proposed an alternative route to Estrada Nacional 4. To better understand the effects of an alternative route to the city of Vendas Novas our study applies an axial map analysis to the city current road network system and the two proposals currently being studied by the local city council and national infrastructure management entity. Based on this analysis a new proposal was drawn by our team to optimize the diversion of traffic from the city centre. Through the application of an axial map analysis, in this study our team hoped to demonstrate and disseminate near the local city management entities the potential and validity of this tool to the current and future planning of cities and, in particular, road networks.info:eu-repo/semantics/publishedVersio
A comparative analysis of the observed white dwarf cooling sequence from globular clusters
We report our study of features at the observed red end of the white dwarf
cooling sequences for three Galactic globular clusters: NGC\,6397, 47\,Tucanae
and M\,4. We use deep colour-magnitude diagrams constructed from archival
Hubble Space Telescope (ACS) to systematically investigate the blue turn at
faint magnitudes and the age determinations for each cluster. We find that the
age difference between NGC\,6397 and 47\,Tuc is 1.98\,Gyr,
consistent with the picture that metal-rich halo clusters were formed later
than metal-poor halo clusters. We self-consistently include the effect of
metallicity on the progenitor age and the initial-to-final mass relation. In
contrast with previous investigations that invoked a single white dwarf mass
for each cluster, the data shows a spread of white dwarf masses that better
reproduce the shape and location of the blue turn. This effect alone, however,
does not completely reproduce the observational data - the blue turn retains
some mystery. In this context, we discuss several other potential problems in
the models. These include possible partial mixing of H and He in the atmosphere
of white dwarf stars, the lack of a good physical description of the
collision-induced absorption process and uncertainties in the opacities at low
temperatures. The latter are already known to be significant in the description
of the cool main sequence. Additionally, we find that the present day local
mass function of NGC\,6397 is consistent with a top-heavy type, while 47\,Tuc
presents a bottom-heavy profile.Comment: Accepted for publication in MNRAS (16 pages, 19 figures
Development and Physicochemical Characterization of Desonide-Loaded Nanocapsule Suspensions
Desonide is a topical corticosteroid that has been used for more than 30 years; however, its prolonged use can induce several side effects, affecting dermis and epidermis. The present work consists of development desonide-loaded nanocapsule suspensions (D-NC) using different polymers (Eudragit S100® or Eudragit L100®) and desonide-loaded lipid-core nanocapsules (D-LNC). They were formulated by interfacial deposition using the preformed polymer method and all formulations showed negative zeta potential and adequate nanotechnological characteristics (particle size 161–202 nm, polydispersity index < 0.20). Simple and sensitive methods using high-performance liquid chromatography (HPLC) were developed to quantify desonide in LNC and to study its release kinetics. The method was linear, specific, precise, and exact and therefore can be applied in quantification of D-NC and D-LNC. We evaluated in vitro methods for drug release (dissolution, Franz diffusion cells, and dialysis sac) and we use mathematical models (monoexponential, biexponential, and Korsmeyer-Peppas) to show release kinetics from this system
Nanostructured Systems Containing Rutin: In Vitro Antioxidant Activity and Photostability Studies
The improvement of the rutin photostability and its prolonged in vitro antioxidant activity were studied by means of its association with nanostructured aqueous dispersions. Rutin-loaded nanocapsules and rutin-loaded nanoemulsion showed mean particle size of 124.30 ± 2.06 and 124.17 ± 1.79, respectively, polydispersity index below 0.20, negative zeta potential, and encapsulation efficiency close to 100%. The in vitro antioxidant activity was evaluated by the formation of free radical ·OH after the exposure of hydrogen peroxide to a UV irradiation system. Rutin-loaded nanostructures showed lower rutin decay rates [(6.1 ± 0.6) 10−3 and (5.1 ± 0.4) 10−3 for nanocapsules and nanoemulsion, respectively] compared to the ethanolic solution [(35.0 ± 3.7) 10−3 min−1] and exposed solution [(40.1 ± 1.7) 10−3 min−1] as well as compared to exposed nanostructured dispersions [(19.5 ± 0.5) 10−3 and (26.6 ± 2.6) 10−3, for nanocapsules and nanoemulsion, respectively]. The presence of the polymeric layer in nanocapsules was fundamental to obtain a prolonged antioxidant activity, even if the mathematical modeling of the in vitro release profiles showed high adsorption of rutin to the particle/droplet surface for both formulations. Rutin-loaded nanostructures represent alternatives to the development of innovative nanomedicines
Efecto insecticida y repelente del aceite de canela sobre moscas asociadas con el ganado
Objetivo. Debido a la mayor resistencia parásita, hay una necesidad de explorar insecticidas alternativos, incluidos los productos naturales, tales como aceites esenciales. En este sentido, el objetivo de este estudio fue evaluar, para el primer equipo, el efecto insecticida y repelente de Cinnamomum zeylanicum (formas libres y nanoemulsión) in vitro e in vivo. Materiales y métodos. Para ello, el efecto insecticida de la forma libre se ensayó a 1.0, 5.0 y 10%, mientras que la forma nanoemulsión se ensayó a 0.5, 1.0 y 5.0% frente a las moscas domésticas adultas, Musca domestica. Para la validación de la prueba, las moscas fueron rociados con el diluyente (agua y triton 10%) y con nanoemulsión en blanco (sin aceite esencial de C. zeylanicum). También, fueron realizados pruebas in vivo usando vacas naturalmente infestadas con Haemotobia irritans. Resultados. Los resultados demostraron que el aceite de canela (10%) y la nanoemulsión (5%) fueron 100% eficaz contra M. domestica después de 90 minutos de exposición. El efecto repelente se ensayó in vivo usando 5% de aceite de canela en vacas Holstein, naturalmente infestados por Haemotobia irritans. Se contaron las moscas a las 0, 1, 2, 3, 9 y 24 h después del tratamiento el aceite de canela. Se verificó disminución significativa (p<0.05) en el número de moscas vivas de vacas canela pulverizada en todo momento. Conclusiones. En base a estos resultados, C. zeylanicum mostró un efecto insecticida (in vitro) contra las moscas domésticas y efecto repelente (in vivo) contra la mosca de los cuernos
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