374 research outputs found

    Epifluorescence microscope methods for bacterial enumeration in a 4-chlorophenol degrading consortium

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    Epifluorescence microscope methods, namely BacLight, direct epifluorescence filter technique and Rhodamine 123, consistently underestimated plate bacterial counts in a 4-chlorophenol degrading consortium. Cells capable of passing through 0.2 mgrm filters, referred as `ultramicrocells', were found. Although cell counts were higher when traditional methods were used, BacLight and direct epifluorescence filter technique were convenient techniques for the systematic monitoring of bacteria involved in biodegradation processes, as results were consistent and available within a short time

    A people-oriented paradigm for smart cities

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    Most works in the literature agree on considering the Internet of Things (IoT) as the base technology to collect information related to smart cities. This information is usually offered as open data for its analysis, and to elaborate statistics or provide services which improve the management of the city, making it more efficient and more comfortable to live in. However, it is not possible to actually improve the quality of life of smart cities’ inhabitants if there is no direct information about them and their experiences. To address this problem, we propose using a social and mobile computation model, called the Internet of People (IoP) which empowers smartphones to recollect information about their users, analyze it to obtain knowledge about their habits, and provide this knowledge as a service creating a collaborative information network. Combining IoT and IoP, we allow the smart city to dynamically adapt its services to the needs of its citizens, promoting their welfare as the main objective of the city.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    O “Outsourcing” dos serviços como recurso estratégico de competitividade internacional da economia portuguesa

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    A globalização dos mercados empresariais dos dias de hoje exige uma visão lógica de atravessamento funcional ligada à criação de valor sobre o ponto de vista de custo, tempo e serviço. A enfatização de novas formas organizacionais e de novos processos de trabalho em termos contratuais deixou hoje de ser vista como um recurso passando a ser entendida como uma necessidade básica fundamental e uma potencial fonte de vantagens competitivas. Nesta medida, este artigo pretende ser um texto de reflexão a partir de uma base teórica devidamente fundamentada e centrada na temática internacionalização e "Outsourcing", tendo como objetivo demonstrar como este último recurso pode ser a resposta ideal e uma influente e poderosa ferramenta de projeção internacional de Portugal, podendo funcionar para um país marcado pela recessão como uma verdadeira fonte de receita em tempos de crise. Na verdade este pode ser de facto o caminho para capitalizar as vantagens de Portugal, melhorar as suas desvantagens, criar postos de trabalho, gerar riqueza, fomentar competitividade internacional e, mais importante ainda, ser a medicina alternativa na cura da doença que é hoje o défice público português, que o tratamento “Outsourcing” poderia eventualmente ajudar a regenerar

    First record of Darwin’s Slimehead, Gephyroberyx darwinii (Johnson, 1866) (Beryciformes: Trachichthyidae), in association with Brazilian deep reefs

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    Copyright © 2004 aqua, International Journal of Ichthyology.Três espécies da família Trachichthyidae ocorrem no sul do Brasil: Paratrachichthys atlanticus, Hoplostethus occidentalis e Gephyroberyx darwinii. Esta última é uma espécie que atinge tamanhos da ordem dos 600 mm (CT), vive na província bentopelágica até profundidades de 1210 metros. É encontrada em águas subtropicais distribuindo-se entre os paralelos 43ºN e 35ºS, sendo utilizada como fonte de alimento no leste do Atlântico central. O presente trabalho reporta a ocorrência de Gephyroberyx darwinii na costa brasileira entre as localidades de Vila Velha (ES) e Rio Grande (RS), em áreas de plataforma externa e talude superior, com profundidades variando de 70 a 520 metros. Suas ocorrências nestas áreas estiveram relacionadas a lances de pesca (onde Lophius gastrophysus é espécie alvo) sobre formações de corais vivos. Dados biométricos e merísticos de três espécimes são apresentados no trabalho.ABSTRACT: Three species of the Trachichthyidae family occur in the south of Brazil: Paratrachichthys atlanticus, Hoplostethus occidentalis and Gephyroberyx darwinii. G. darwinii may attain a length of 600 mm (TL). This benthopelagic species occurs at depths down to 1210 m and is generally found in subtropical waters between 43ºN and 35ºS. It is commercially exploited in the east central Atlantic for food and for oil. In this paper we report the occurrence of G. darwinii off the south and south-east coasts of Brazil between Vila Velha (Espírito Santo State) and Rio Grande (Rio Grande do Sul State), in outer shelf and slope areas, at depths between 70 and 520 m. In Brazil the trachichthyids were usually caught while fishing for Lophius gastrophysus over deep coral bottoms. Meristic and biometric data are presented for the three collected specimens

    A comparison between pure active pharmaceutical ingredients and therapeutic deep eutectic solvents: solubility and permeability studies

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    THEDES, so called therapeutic deep eutectic solvents are here defined as a mixture of two components, which at a particular molar composition become liquid at room temperature and in which one of them is an active pharmaceutical ingredient (API). In this work, THEDES based on menthol complexed with three different APIs, ibuprofen (ibu), BA (BA) and phenylacetic acid (PA), were prepared. The interactions between the components that constitute the THEDES were studied by NMR, confirming that the eutectic system is formed by H-bonds between menthol and the API. The mobility of the THEDES components was studied by PFGSE NMR spectroscopy. It was determined that the self-diffusion of the species followed the same behavior as observed previously for ionic liquids, in which the components migrate via jumping between voids in the suprastructure created by punctual thermal fluctuations. The solubility and permeability of the systems in an isotonic solution was evaluated and a comparison with the pure APIs was established through diffusion and permeability studies carried out in a Franz cell. The solubility of the APIs when in the THEDES system can be improved up to 12 fold, namely for the system containing ibu. Furthermore, for this system the permeability was calculated to be 14 105 cm/s representing a 3 fold increase in comparison with the pure API. With the exception of the systems containing PA an increase in the solubility, coupled with an increase in permeability was observed. In this work, we hence demonstrate the efficiency of THEDES as a new formulation for the enhancement of the bioavailability of APIs by changing the physical state of the molecules from a solid dosage to a liquid system.he European Union’s Seventh Framework Programme (FP7/2007- 2013) under grant agreement nREGPOT-CT2012-316331- POLARIS and from Project ‘‘Novel smart and biomimetic materials for innovative regenerative medicine approaches (Ref.: RL1 - ABMR - NORTE-01-0124-FEDER-000016)” co-financed by North Portugal Regional Operational Programme (ON.2 – O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF). Funding was also provided by Fundação para a Ciência e a Tecnologia, through contracts LAQV-REQUIMTE: UID/QUI/50006/2013 and UCIBIOREQUIMTE: UID/Multi/04378/2013. This work was co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01- 0145-FEDER-007728).info:eu-repo/semantics/publishedVersio

    Assessment of dye distribution in sensitized solar cells by microprobe techniques

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    Dye sensitized solar cells (DSCs) have received considerable attention once this technology offers economic and environmental advantages over conventional photovoltaic (PV) devices. The PV performance of a DSC relies on the characteristics of its photoanode, which typically consists of a nanocrystalline porous TiO2 film, enabled with a large adsorptive surface area. Dye molecules that capture photons from light during device operation are attached to the film nanoparticles. The effective loading of the dye in the TiO2 electrode is of paramount relevance for controlling and optimizing solar cell parameters. Relatively few methods are known today for quantitative evaluation of the total dye adsorbed on the film. In this context, microprobe techniques come out as suitable tools to evaluate the dye surface distribution and depth profile in sensitized films. Electron Probe Microanalysis (EPMA) and Ion Beam Analytical (IBA) techniques using a micro-ion beam were used to quantify and to study the distribution of the Ru organometallic dye in TiO2 films, making use of the different penetration depth and beam sizes of each technique. Different 1D nanostructured TiO2 films were prepared, morphologically characterized by SEM, sensitized and analyzed by the referred techniques. Dye load evaluation in different TiO2 films by three different techniques (PIXE, RBS and EPMA/WDS) provided similar results of Ru/Ti mass fraction ratio. Moreover, it was possible to assess dye surface distribution and its depth profile, by means of Ru signal, and to visualize the dye distribution in sample cross-section through X-ray mapping by EPMA/EDS. PIXE maps of Ru and Ti indicated an homogeneous surface distribution. The assessment of Ru depth profile by RBS showed that some films have homogeneous Ru depth distribution while others present different Ru concentration in the top layer (2 lm thickness). These results are consistent with the EPMA/EDS maps obtained

    Microscopy techniques for dye distribution in DSCs nanocrystalline TiO2 films 

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    Capture of sunlight has attracted an increasing interest in the scientific community and triggered the development of efficient and cheap photovoltaic devices. Amongst recent generation technologies for solar energy conversion, dye-sensitized solar cells (DSCs) show an optimal trade-off between high-conversion efficiency and low-cost manufacturing. For the last two decades, significant progress has been made and best energy conversion efficiency of the DSC at the laboratory scale has surpassed 12% [1]. A lot of work has focused on the enlargement of surface areas to enhance the amount of adsorbed dyes by reduction of nanoparticle sizes or utilization of novel structures. Nevertheless there remain some crucial details of DSC operation for which limited information is available, namely dye diffusion and adsorption, surface coverage and dye distribution throughout the nc-TiO2 film. Microprobe techniques can be powerful tools to evaluate the dye load, the dye distribution and dye depth profile in sensitized films. Electron Probe Microanalysis (EPMA) and Ion Beam Analytical (IBA) techniques using a micro-ion beam, namely micro-Particle Induced X-ray Emission ( PIXE) and Rutherford Backscattering Spectrometry (RBS), were used to quantify and to study the distribution of the ruthenium organometallic (N719) dye in TiO2 films, profiting from the different penetration depth and beam sizes of each technique. Two different types of films were prepared and sensitized, mesoporous nanoparticles and 1D nanostructured TiO2 films (figure 1). Despite the low concentration of Ru, the high sensitive analytical techniques used allowed to assess the Ru surface distribution and depth profile. Fig. 2 shows the PIXE maps of Ru and Ti indicating an homogeneous surface distribution. The same figure presents the RBS spectra obtained with a 2 MeV proton beam of the same sample showing that a good spectra fit is obtained considering only two sample layers: the first one with a 1.7 ìm thickness; the second one being the SiO2 substrate. The Ru RBS signal also shows that the dye has an homogeneous depth distribution. Due to the fine spatial resolution of the EPMA/WDS (Wavelength Dispersive Spectroscopy) technique it was possible to visualise the dye distribution in sample cross-section (with micrometer or submicrometer dimensions) as presented in Fig. 3 for the elemental mapping of a mesoporous nanoparticle TiO2 film. Dye load evaluation by two different techniques (ìPIXE and EPMA/WDS) provided similar results (Ru/Ti values around 0.5 %). The distribution analysis of the organometallic dye (N719) was done through ruthenium distribution via X-ray mapping. RBS was used to assess the ruthenium depth profile. This assessment can lead to a better understanding of the device performance

    Dye assessment in nanostructured TiO2 sensitized films by microprobe techniques

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    Dye sensitized solar cells (DSCs) have received considerable attention once this technology offers economic and environmental advantages over conventional photovoltaic (PV) devices. The PV performance of a DSC relies on the characteristics of its photoanode, which typically consists of a nanocrystalline porous TiO2 film, enabled with a large adsorptive surface area. Dye molecules that capture photons from light during device operation are attached to the film nanoparticles. The effective loading of the dye in the TiO2 electrode is of utmost importance for controlling and optimizing solar cell parameters. Relatively few methods are known today for quantitative evaluation of the total dye adsorbed on the film. In this work, a new approach combining microprobe techniques namely, Ion Beam Analytical (IBA) techniques using a micro-ion beam (Rutherford Backscattering Spectrometry (RBS) and Particle Induced X-ray Emission (PIXE)) and Electron Probe Micro-Analysis (EPMA) was carried out to assess dye distribution and depth profile in TiO2 films and the dye load based on Ru/Ti mass ratio. Different 1D nanostructured TiO2 films were prepared, morphologically characterised by SEM, sensitized and analysed by the referred techniques. Dye load evaluation in different TiO2 films by three different techniques (PIXE, RBS and EPMA/ wavelength dispersive spectrometry (WDS)) provided similar results of Ru/Ti mass fraction ratio. Moreover, it was possible to assess dye surface distribution and its depth profile, by means of Ru signal, and to visualise the dye distribution in sample cross-section through X-ray mapping by EPMA/ energy dispersive spectrometry (EDS). PIXE maps of Ru and Ti indicated an homogeneous surface distribution. The assessment of ruthenium depth profile by RBS showed that some films have homogeneous Ru depth distribution while others present different Ru concentration in the top layer (2 ìm thickness). These results are consistent with the EPMA/EDS maps obtained. EPMA (WDS and EDS) together with IBA techniques proved to be powerful tools for functional materials characterisation and provided very promising results in the study of nanostructured TiO2 sensitized films
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