A versatile reactor for continuous monitoring of biofilm properties in laboratory and industrial conditions

Aims: The understanding of the dynamics of surface microbial colonization with concomitant monitoring of biofilm formation requires the development of biofilm reactors that enable direct and real-time evaluation under different hydrodynamic conditions. Methods and Results: This work proposes and discusses a simple flow cell reactor that provides a means to monitoring biofilm growth by periodical removing biofilm-attached slides for off-line, both non-destructive and destructive biofilm analyses. This is managed without the stoppage of the flow, thus reducing the contamination and the disturbance of the biofilm development. With this flow cell, biofilm growth and respiratory activity can be easily followed, either in well-defined laboratory conditions or in an industrial environment. Conclusions, Significance and Impact of the Study: The reproducible and typical biofilm development curves obtained, validated this flow cell and confirmed its potential for different biofilm-related studies, which can include biocidal treatment.Instituto de Biotecnologia e Química Fina(IBQF)

Influence of medium composition on the characteristics of a denitrifying biofilm formed by alcaligenes denitrificans in a fluidised bed reactor

The influence of the ratio carbon/nitrogen and phosphorus concentration on the performance of a biofilm fluidised bed reactor used for denitrification and on the properties of the biofilm was studied. Although the removal efficiencies of C and N reached steady-state values, the thickness of the biofilm steadily increased. The dry density of the biofilm did not seem to be dependent on the loading conditions, although a denser biofilm was obtained when there was no nutrient limitation that corresponded to the complete removal of nitrate and carbon. The composition of the biofilm in terms of proteins and polysaccharides changed with the C/N ratio and P concentrations. Higher denitrifying activities, which were obtained with increasing P concentrations, were related with higher protein content, since metabolism was shifted from polysaccharide production towards cell production. The thickness and the density of the biofilms were related mainly with the shear stress in the reactor and the composition of biofilms was dependent on the composition of the medium and related with higher activities of the microorganisms.Fundação para a Ciência e a Tecnologia (FCT) - PRAXIS XXI . Instituto de Biotecnologia e Química Fina (IBQF)

Desenvolvimento de recursos didácticos informatizados no âmbito da educação para o desenvolvimento sustentável. o exemplo do courseware SeRe

A falta de recursos didácticos informatizados de qualidade para o 1º e 2º Ciclos do Ensino Básico (1º/2º CEB), concebidos no âmbito da Educação para o Desenvolvimento Sustentável (EDS), numa perspectiva de Ensino por Pesquisa, determinou a organização de uma equipa multidisciplinar para o desenvolvimento do «Courseware Sere - O Ser Humano e os Recursos Naturais». Ajustando alguns princípios de desenvolvimento de software, particularmente de Design Centrado no Utilizador (DCU), o trabalho da equipa multidisciplinar, constituída por elementos com diversas competências (ao nível da Didáctica das Ciências, da Tecnologia Educativa, de Design e de Programação), centrou-se no desenvolvimento de um recurso didáctico informatizado que integra várias tipologias de software, nomeadamente simulações e visualizações, com as actividades didácticas. A orientação do recurso, as temáticas propostas e as metodologias e estratégias de exploração privilegiadas fundamentam-se: i) na identificação das orientações nacionais e internacionais da EDS; ii) na identificação das necessidades e interesses dos professores quanto à implementação de actividades com orientação EDS (Sá, 2008; Sá e Martins, 2007), iii) no paradigma de ensino por competências (Cachapuz, Sá-Chaves e Paixão, 2004) e iv) no recurso a um design interactivo centrado no utilizador (Costa, Loureiro, Reis, Sá, Guerra e Vieira, 2009; Guerra, 2007). Neste artigo faz-se uma apresentação do processo de desenvolvimento do recurso didáctico, das temáticas propostas e das metodologias e estratégias de exploração perspectivadas pelos autores do recurs

The role of pyrimidine and water as underlying molecular constituents for describing radiation damage in living tissue: A comparative study

8 págs.; 7 figs.; 2 tabs.© 2015 AIP Publishing LLC. Water is often used as the medium for characterizing the effects of radiation on living tissue. However, in this study, charged-particle track simulations are employed to quantify the induced physicochemical and potential biological implications when a primary ionising particle with energy 10 keV strikes a medium made up entirely of water or pyrimidine. Note that pyrimidine was chosen as the DNA/RNA bases cytosine, thymine, and uracil can be considered pyrimidine derivatives. This study aims to assess the influence of the choice of medium on the charged-particle transport, and identify how appropriate it is to use water as the default medium to describe the effects of ionising radiation on living tissue. Based on the respective electron interaction cross sections, we provide a model, which allows the study of radiation effects not only in terms of energy deposition (absorbed dose and stopping power) but also in terms of the number of induced molecular processes. Results of these parameters for water and pyrimidine are presented and compared.This research was supported by the Australian Research Council (ARC) through its Centres of Excellence Program. D.B.J. thanks the ARC for provision of a Discovery Early Career Researcher Award. We also acknowledge the support of the Spanish Ministerio de Economia y Competitivad under Project No. FIS 2012-31230 and the European Union COST Actions (MP1002 and CM1301). P.L.V. acknowledges the Portuguese Foundation for Science and Technology (FCTMEC) through research grants PTDC/FIS-ATO/1832/2012, UID/FIS/00068/2013, and SFRH/BSAB/105792/2014. P.L.V. also acknowledges his Visiting Professor position at Flinders University, Adelaide, South Australia.Peer Reviewe

Electron-scattering cross sections for collisions with tetrahydrofuran from 50 to 5000 eV

In this paper, we report on total electron tetrahydrofuran (C4 H8 O) scattering cross-section measurements for energies in the range from 50 to 5000 eV with experimental errors of about 5%. In addition, integral elastic and inelastic cross sections have been calculated over a broad energy range (1-10000 eV), with an optical potential method assuming a screening-corrected independent atom representation. Partial and total ionization cross sections have been also obtained by combining simultaneous electron and ion measurements with a time-of-flight analysis of the ionic induced fragmentation. Finally, an average energy distribution of secondary electrons has been derived from these measurements in order to provide data for modeling electron-induced damage in biomolecular systems. © 2009 The American Physical Society.de Educación y Ciencia Plan Nacional de Física, This study has been partially supported by the following research projects and institutions: Ministerio Project No. FIS2006-00702, Consejo de Seguridad Nuclear CSN, European Science Foundation COST Action CM0601 and EIPAM Project, Acciones Integradas Hispano-Portuguesas Project No. HP2006-0042Peer Reviewe

QUANTIFILER®TRIO DNA method performance in a collection of ancient samples

Trabalho científico apresentado sob a forma de Poster no evento 9th ISABS Conference on Forensic Anthropologic Genetics and Mayo Clinicm Bol, Island of Brac, Croacia, 2015During the past few years significant progress has been made in solving technical challenges associated with STR profiling including the ability to analyze degraded DNA and low amounts of DNA. The result of these changes is that useful STR profiles can now be obtained from previously untypeable forensic DNA samples. Analysis of DNA from ancient material represents an important role in molecular anthropology, although there are many limitations concerning low DNA quantity and/or degraded DNA, and/or PCR inhibitors. These factors can make it difficult to decide whether to continue with STR analysis, which STR panel to use and how much DNA to add to PCR reaction. With all these constraints, DNA quantification represents an important tool to decide which method will follow in order to improve workflow and have good results in less time-consuming. The Quantifiler® Trio DNA method provides a quality index (QI) to detect the presence of degraded DNA along with PCR inhibitors.This guide allows the selection of the optimal short tandem repeat (STR) analysis chemistry (autosomal, or miniSTR) and streamlines the workflow while increasing downstream analysis success rates. In order to compare DNA quality from different extraction methods, samples from 46 exhumed Middle Ages individuals were extracted with modified phenol-chloroform method and also PrepFiler Express BTA™ method. DNA was quantified with Quantifiler® Trio DNA Quantification in an Applied Biosystems® 7500 Real-Time PCR System. Results were analyzed and allow us to point Quantifiler® Trio method as an important tool in pre-STR typing methods in ancient samplesN/

Optimization of the cold profiling process through SMED

In a more and more competitive and industrialized market, it is essential that companies realize that the way forward must go through the optimization of their production processes, reducing the costs and increasing product quality. Nowadays it’s necessary to adopt innovative management models that can provide increased productivity at minimal costs, such as the Lean thinking. The metalworking industry is integrated into one of the most competitive existing markets in Portugal. Given this, it’s fundamental to reduce the waste in all sectors of the production process, using the good Lean principles and practices, such as the Single Minute Exchange of Die, also known as SMED methodology. This paper presents a project of implementing the SMED methodology in the cold profiling process, in a population of five different profiling machines. The results of the SMED implementation show an average OEE improvement of 10,8%.info:eu-repo/semantics/publishedVersio