Design, synthesis and validation of an inhibitor of CGRP degradation

Introduction: In addition to their afferent role in detection and signalling noxious stimuli, neuropeptide-containing sensory nerves may initiate and maintain chronic inflammation in diseases such as periodontitis by an efferent process known as neurogenic inflammation. Neuropeptides are susceptible to cleavage by peptidases, and therefore, the exact location and level of expression of peptidases are major determinants of neuropeptide action. Previous studies in our laboratory showed that enzyme components of gingival crevicular fluid (GCF) from periodontitis sites selectively inactivated the neuropeptide calcitonin gene-related peptide (CGRP), known to have a role in inhibiting osteoclastic bone resorption. Objectives: The aim of this study was to design and synthesise a specific inhibitor to prevent the degradation of CGRP by components of GCF. Methods: A hydroxamate-based inhibitor with a biotinylated tag was designed to ensure selectivity for CGRP and ease of use for future purification strategies. The biotinylated peptide hydroxamate contained the P1-P4 amino acid sequence of the potential CGRP cleavage site and was synthesised by solid-phase methods using standard Fmoc chemistry. Inhibition of CGRP metabolism by GCF was determined by MALDI-mass spectrometry (MALDI-MS) using pooled GCF samples from periodontitis patients as a crude source of the CGRP-degrading enzyme. Results: MALDI-MS analysis of CGRP degradation showed almost complete inhibition in the presence of the biotinylated inhibitor. Our results showed that the rate-limiting step in the cleavage of CGRP is endopeptidase cleavage, followed by carboxypeptidase attack. Conclusion: This study demonstrates that the enzyme component of GCF responsible for the degradation of CGRP can be inhibited by a biotinylated hydroxamate modelled on a potential endopeptidase cleavage site. The biotin tag on the inhibitor will facilitate our future purification of the CGRP-cleavage enzyme using a streptavidin-agarose column.

Validation of night blindness reports among children and women in a vitamin A deficient population in rural Tanzania.

OBJECTIVE: This study validates different definitions of reported night blindness (XN) in a vitamin A deficient African population with no local term for XN. DESIGN: Case-control study with follow-up after treatment. SETTING: Eight primary schools and health centres in rural Tanzania. SUBJECTS: A total of 1214 participants were screened for reported XN and other eye signs of xerophthalmia: 461 children aged 24-71 months, 562 primary school-age children and 191 pregnant or breast-feeding women. All 152 cases of reported XN were selected for the validation study and group matched with 321 controls who did not complain of XN. XN reports were validated against serum retinol concentrations and pupillary dark adaptation measurements in cases and controls. INTERVENTION: All children and women who reported XN or had other signs of active xerophthalmia were treated with vitamin A and followed up 3-4 weeks later. Half of the untreated control group who had their serum retinol examined in the baseline examination were also followed up. RESULTS: The overall prevalence of reported XN was 12.5%. At baseline, mean pupillary threshold (-1.52 vs -1.55 log cd/m(2), P=0.501) and median serum retinol concentrations (0.95 vs 0.93 micromol/l, P=0.734) were not significantly different in cases and controls either overall or in each population group. More restricted case definitions reduced the prevalence of reported XN to 5.5% (P<0.001), but there was still no significant difference between cases and controls although the results were in the expected direction. After treatment, the median serum retinol concentration improved significantly only in the most deficient group, the young children. Dark adaptation improved in all the subgroups but the difference was only significant for young children and primary school-age children when the restricted case definitions were used. CONCLUSIONS: XN reports are a poor indicator of vitamin A deficiency in this population. SPONSORSHIP: Task Force Sight and Life, Basel, Switzerland.

Wishful Thinking: Lessons from the internal and external evaluations of an innovatory education project in Northern Ireland

From March 1999 to August 2000, the authors were involved in simultaneous internal and external evaluations of the social civic and political education (SCaPE) project in Northern Ireland. This project was a major initiative established by the Citizenship Foundation, the Northern Ireland Council for the Curriculum, Examination and Assessment (CCEA), and the School of Education at the University of Ulster at Coleraine. It was a 2-year project in 25 secondary schools established to design, develop, pilot and evaluate a new programme of social, civic and political education for Northern Ireland. It also aimed to serve as a model for future Citizenship curriculum developments throughout Northern Ireland and elsewhere. This paper describes the background to the project, the design and conduct of the two evaluations, and the links between them. It outlines the main conclusions of each evaluation and describes the way SCaPE has since evolved into a mainstream curriculum development project. The final part of the paper analyses the key opportunities, tensions and challenges involved in running such evaluations at a critical time in the history of Northern Ireland – a time when innovation is both necessary and controversial. It argues that, especially in such circumstances, evaluation cannot be conducted from a neutral, objective standpoint, and that it is incumbent on evaluators to recognise the emotional, personal and political commitment they make to the projects in which they are engaged.

Development and Validation of a Procedure for Numerical Vibration Analysis of an Oscillating Wave Surge Converter

During extreme sea states so called impact events can be observed on the wave energy converter Oyster. In small scale experimental tests these impact events cause high frequency signals in the measured load which decrease confidence in the data obtained. These loads depend on the structural dynamics of the model. Amplification of the loads can occur and is transferred through the structure from the point of impact to the load cell located in the foundation. Since the determination of design data and load cases for Wave Energy Converters originate from scale experiments, this lack of confidence has a direct effect on the development.

Numerical vibration analysis is a valuable tool in the research of the structural load response of Oyster to impact events, but must take into account the effect of the surrounding water. This can be done efficiently by adding an added mass distribution, computed with a linearised potential boundary element method. This paper presents the development and validation of a numerical procedure, which couples the OpenSource boundary element code NEMOH with the Finite Element Analysis tool CodeAster. Numerical results of the natural frequencies and mode shapes of the structure under the influence of added mass due to specific structural modes are compared with experimental results.

Validation of a high-throughput immunobead array technique for multiplex detection of three foodborne pathogens in chicken products

This study rigorously evaluated a previously developed immunobead array method to simultaneously detect three important foodborne pathogens, Campylobacter jejuni, Listeria monocytogenes, and Salmonella spp., for its actual application in routine food testing. Due to the limitation of the detection limit of the developed method, an enrichment step was included in this study by using Campylobacter Enrichment Broth for C. jejuni and Universal Pre-enrichment Broth for L. monocytogenes and Salmonella spp.. The findings show that the immunobead array method was capable of detecting as low as 1 CFU of the pathogens spiked in the culture media after being cultured for 24 hours for all three pathogens. The immunobead array method was further evaluated for its pathogen detection capabilities in ready-to-eat (RTE) and ready-to-cook (RTC) chicken samples and proven to be able to detect as low as 1 CFU of the pathogens spiked in the food samples after being cultured for 24 hours in the case of Salmonella spp., and L. monocytogenes and 48 hours in the case of C. jejuni. The method was subsequently validated with three types of chicken products (RTE, n=30; RTC, n=20; raw chicken, n=20) and was found to give the same results as the conventional plating method. Our findings demonstrated that the previously developed immunobead array method could be used for actual food testing with minimal enrichment period of only 52 hours, whereas the conventional ISO protocols for the same pathogens take 90-144 hours. The immunobead array was therefore an inexpensive, rapid and simple method for the food testing.

Validation of a 3D damage model for predicting the response of composite structures under crushing loads

A 3D intralaminar continuum damage mechanics based material model, combining damage mode interaction and material nonlinearity, was developed to predict the damage response of composite structures undergoing crush loading. This model captures the structural response without the need for calibration of experimentally determined material parameters. When used in the design of energy absorbing composite structures, it can reduce the dependence on physical testing. This paper validates this model against experimental data obtained from the literature and in-house testing. Results show that the model can predict the force response of the crushed composite structures with good accuracy. The simulated energy absorption in each test case was within 12% of the experimental value. Post-crush deformation and the damage morphologies, such as ply splitting, splaying and breakage, were also accurately reproduced. This study establishes the capability of this damage model for predicting the responses of composite structures under crushing loads.

Project Management within an Urban Site Context: Issues considering External Stakeholders

Large construction projects create numerous hazards, making it one of the most dangerous industries in which to work. This element of risk increases in urban areas and can have a negative impact on the external stakeholders associated with the project, along with their surrounding environments. The aim of this paper is to identify and document, in an urban context, the numerous issues encountered by on-site project managers from external stakeholders and how they affect a construction project. In addressing this aim, the core objective is to identify what issues are involved in the management of these stakeholders. In order to meet this requirement, a qualitative methodology encompassing an informative literature review followed by five individual case study interviews. The data gathered is assessed qualitatively using mind mapping software. A number of issues are identified which have an impact on the external stakeholders involved, and also how they affected proceedings on site. Collectively the most commonly occurring issues are environmental, legal, health and safety and communication issues. These ranged from road closures and traffic disruption to noise, dust and vibrations from site works. It is anticipated that the results of this study will assist and aid project managers in identifying issues considering external stakeholders, particularly on urban construction projects. A wide range of issues can develop depending on the complexity and nature of each project, but this research will illustrate and reinforce to project managers, that identifying issues early, effective communication and appropriate liaising can be used to manage the issues considering external stakeholders.

Calibration and validation of hydrodynamic, salt and heat transport models for Ria de Aveiro lagoon (Portugal)

Ria deAveiro is a very complex shallow water coastal lagoon located on the northwest of Portugal. Important issues would be left unanswered without a good understanding of hydrodynamic and transport processes occurring in the lagoon. Calibration and validation of hydrodynamic, salt and heat transport models for Ria de Aveiro lagoon are presented. The calibration of the hydrodynamic model was performed adjusting the bottom friction coefficient, through the comparison between measured and predicted time series of sea surface elevation for 22 stations. Harmonic analysis was performed in order to evaluate the model's accuracy. To validate the hydrodynamic model measured and predicted SSE values were compared for 11 stations, as well as main flow direction velocities for 10 stations. The salt and heat transport models were calibrated comparing measured and predicted time series of salinity and water temperature for 7 stations, and the RMS of the difference between the series was determined. These models were validated comparing the model results with an independent field data set. The hydrodynamic and the salt and heat transport models for Ria de Aveiro were successfully calibrated and validated. They reproduce accurately the barotropic flows and can therefore adequately represent the salt and heat transport and the heat transfer processes occurring in Ria deAveiro.

(Re)configuração das práticas educativas na prevenção do stresse na infância

O presente trabalho resulta do estudo que procurou analisar a reconfiguração das práticas educativas na prevenção do stresse na infância. O principal objetivo foi o de analisar de que forma os educadores podem desenvolver práticas educativas, estruturadoras e estruturantes do bem-estar da criança, investindo intencionalmente no desenvolvimento de atividades educativas, de modo a prevenir os índices de stresse das crianças, na educação pré-escolar. Foram realizados cinco estudos complementares, de natureza quantitativa e qualitativa. O estudo 1: contextualização e caracterização de indicadores sociofamiliares de crianças que frequentam a educação pré-escolar; Estudo 2: adaptação/avaliação do PKBS-2 de Merrell, para identificação das aptidões sociais e os problemas de comportamento em crianças dos 3 aos 6 anos numa amostra portuguesa (N=150) e estudos comparativos Portugal/Brasil (N=300) e Portugal/Cabo-Verde (N=150); Estudo 3: validação da Escala Comportamental para crianças em idade Pré-Escolar – PKBSpt, versão portuguesa do PKBS-2 em crianças dos 2 aos 7 anos (N=581); Estudo 4: contributos para a reconfiguração das práticas pedagógicas e o stresse na infância sob o olhar dos educadores. No âmbito deste estudo 4, desenvolvemos e validamos o Protocolo para a Avaliação do Stresse na Infância–PASI, constituído por três subescalas que aplicamos a educadores ou equiparados (N=188): ESISI, EPELSI e ECPLSI; Estudo 5: análise das competências dos profissionais da educação ao nível da ansiedade (IAB de Beck) e estratégias de coping; (EC de Gomes & Pereira). Para análise estatística dos dados utilizamos o programa SPSS e o Excel. Os resultados evidenciaram a validade e fidelidade dos instrumentos: ESISI, EPELSI, ECPLSI e PKBSpt, bem como a validação para a língua portuguesa deste último. A variável género apresentou diferenças estatisticamente significativas nas aptidões sociais e problemas de comportamento, no entanto não estão correlacionadas com os problemas de ansiedade. Os Educadores focalizam a sua praxis educativa na observação, identificação e definição de estratégias orientadas para o stresse na infância e, ainda, na cooperação escola/família e na prevenção das situações indutoras de stresse. Contudo apontam algumas fragilidades na formação básica e contínua, para lidarem com o stresse na primeira infância. As causas psicossociais são preditoras das situações indutoras de stresse na infância e são explicadas pelas causas externas de componente escolar, ou seja, as perturbações de ansiedade na infância poderão ter repercussões no contexto escolar. Importa que a comunidade educativa perspetive particular atenção às crianças que estão em situação de maior vulnerabilidade, de modo a prevenir e a intervir nas situações de stresse na educação pré-escolar. São referidas implicações psicopedagógicas deste estudo.

Comunidades de prática online: contributos para a prática letiva: um estudo de caso no âmbito da educação em ciência envolvendo professores e investigadores

As comunidades de prática (CoP), bem como a investigação-ação, têm vindo a ser apontadas na literatura como formas de promover o desenvolvimento profissional de professores, potenciando a melhoria das suas práticas letivas. Contudo, as evidências empíricas relativas às práticas letivas desenvolvidas por professores no âmbito dessas configurações sociais são escassas. Neste estudo procura-se contribuir para colmatar essa lacuna ao analisar uma CoP online, que envolveu professores de ciências e investigadores em Educação em Ciência (EC) e se constituiu no âmbito do projeto “Investigação e práticas lectivas em Educação em Ciência: Dinâmicas de interacção” (IPEC), com enfoques distintos, a que se alude abaixo. A investigação realizada envolveu uma metodologia de natureza predominantemente qualitativa, descritiva, exploratória e do tipo estudo de caso único, sendo o caso as práticas letivas desenvolvidas pelos membros da CoP referida e as dinâmicas de interação entre os mesmos. Como técnicas de recolha de dados, recorreu-se principalmente à observação mediada pela plataforma online de apoio ao desenvolvimento do projeto (dados estatísticos e as mensagens registadas automaticamente) e recolha de documentos. Quanto às técnicas de análise de dados, optou-se principalmente pela análise de conteúdo e análise documental interna, tendo-se triangulado dados de diferentes fontes. Com base no Interconnected Model of Teacher Professional Growth, que Clarke e Hollingsworth propuseram em 2002, e em instrumentos de análise resultantes da revisão de literatura, adaptados aos enfoques definidos, a análise da CoP selecionada incidiu sobre: a) os domínios externo e das práticas de desenvolvimento curricular (DC), ou seja, as suas dinâmicas de interação durante dois anos letivos; b) o domínio das consequências nas práticas letivas, no que concerne às estratégias de ensino de ciências desenvolvidas; c) a evidências do seu carater inovador; e d) aos princípios de DC operacionalizados através do módulo curricular desenhado, implementado, avaliado e disseminado pelos membros da CoP. Os resultados indicam que a) a participação dos membros variou ao longo do período de interação e que a sua dinâmica se enquadra numa adaptação das fases de desenvolvimento de CoP proposta por Wenger e colegas em 2002, com dois ciclos de investigação-ação; b) a CoP desenvolveu estratégias de ensino diversificadas, pouco exploradas por professores e coerentes com diversas recomendações da literatura, de forma consistente; c) as práticas letivas são inovadoras, do tipo challenging, tendo incluído o envolvimento de professores que lecionavam nas escolas dos professores membros da CoP; e d) a CoP operacionalizou vários princípios de DC recomendados na literatura, nomeadamente a flexibilidade e diferenciação. Os resultados empíricos permitiram ainda validar as dimensões do modelo de Clarke e Hollingsworth, assim como adaptar à especificidade do caso analisado.Pelo acima referido, embora reconhecendo as limitações do estudo, nomeadamente relativas às opções metodológicas efetuadas, foi possível inferir que o trabalho realizado no seio desta CoP online de professores e investigadores contribuiu para a inovação e melhoria de práticas letivas de EC. Do estudo resultam ainda instrumentos de análise que se consideram relevantes, dado poderem vir a ser usados em investigações futuras, assim como poderem vir a orientar professores de ciências que desejem alinhar as suas práticas de ensino com recomendações da investigação em EC. Por fim, são apresentadas recomendações relativamente ao envolvimento de professores e investigadores em CoP online, no âmbito da EC, assim como relativamente a possibilidades ao nível de investigações futuras, nomeadamente a validação dos instrumentos e das recomendações apresentadas em contextos mais abrangentes e transversais.

Absorption coefficient of particulate matter on the south-west coast of Europe: a contribution to the validation of the MERIS-Medium Resolution Imaging Spectrometer sensor

Dissolved oxygen (DO) is one of the most important environmental variables of water quality, especially for marine life. Consequently, oxygen is one of the Chemical Quality Elements required for the implementation of European Union Water Framework Directive. This study uses the example of the Ria Formosa, a meso-tidal lagoon on the south coast of Portugal to demonstrate how monitoring of water quality for coastal waters must be well designed to identify symptoms of episodic hypoxia. New data from the western end of the Ria Formosa were compared to values in a database of historical data and in the published literature to identify long-term trends. The dissolved oxygen concentration values in the database and in the literature were generally higher than those found in this study, where episodic hypoxia was observed during the summer. Analysis of the database showed that the discrepancy was probably related with the time and the sites where the samples had been collected, rather than a long-term trend. The most problematic situations were within the inner lagoon near the city of Faro, where episodic hypoxia (<2 mg dm3 DO) occurred regularly in the early morning. These results emphasise the need for a balanced sampling strategy for oxygen monitoring which includes all periods of the day and night, as well as a representative range of sites throughout the lagoon. Such a strategy would provide adequate data to apply management measures to reduce the risk of more persistent hypoxia that would impact on the ecological, important natural resource. economic and leisure uses of this important natural resource.

Disparity energy model with keypoint disparity validation

A biological disparity energy model can estimate local depth information by using a population of V1 complex cells. Instead of applying an analytical model which explicitly involves cell parameters like spatial frequency, orientation, binocular phase and position difference, we developed a model which only involves the cells’ responses, such that disparity can be extracted from a population code, using only a set of previously trained cells with random-dot stereograms of uniform disparity. Despite good results in smooth regions, the model needs complementary processing, notably at depth transitions. We therefore introduce a new model to extract disparity at keypoints such as edge junctions, line endings and points with large curvature. Responses of end-stopped cells serve to detect keypoints, and those of simple cells are used to detect orientations of their underlying line and edge structures. Annotated keypoints are then used in the leftright matching process, with a hierarchical, multi-scale tree structure and a saliency map to segregate disparity. By combining both models we can (re)define depth transitions and regions where the disparity energy model is less accurate.

Validation d'un modèle de formation en ligne portant sur le soutien nutritionnel auprès des diététistes.

Cet essai présente les résultats d'une recherche expérimentation en vue de valider un modèle de formation en ligne auprès des diététistes. Les besoins accrus de formation suscités par le nouveau cadre normatif amènent l'Ordre professionnel des diététistes du Québec (OPDQ) à développer différents moyens de perfectionnement pour ses membres. Bien que les moyens actuellement disponibles soient assez diversifiés, il importe de pouvoir offrir au plus grand nombre possible une offre de formation de haut niveau afin d'assurer e développement des compétences des diététistes. Comme l'OPDQ n'a pas les effectifs nécessaires pour former rapidement un grand nombre de personnes dispersées géographiquement, il devient intéressant d'explorer des moyens de formation complémentaires et d'envisager exploiter les possibilités offertes par la formation en ligne. C'est ainsi que l'auteure de cette recherche a constaté que l'ajout d'une offre complémentaire de formation en ligne pourrait grandement profiter aux diététistes afin de les aider à mieux répondre à l'obligation de mise à jour de leurs connaissances. Une enquête réalisée à l'été 2006 auprès des membres de l'OPDQ confirmait l'intérêt des répondantes pour ce type de formation ainsi que la présence des habiletés technologiques nécessaires. Les données alors recueillies ont permis de cibler une compétence à développer et d'expérimenter, auprès des diététistes, un modèle de formation en ligne portant sur le choix de la voie d'alimentation appropriée. Les objectifs spécifiques de la recherche expérimentation consistaient à élaborer un modèle de formation en ligne pour ensuite l'expérimenter auprès d'un groupe pilote de diététistes en exercice afin d'en évaluer le potentiel. Ce modèle identifiait les dimensions à considérer en ce qui concerne les apprenantes et les apprenants, leur accompagnement, le choix de la compétence et l'élaboration du système d'apprentissage.

Validation of a method for the analysis of volatile organic compounds in water

Dissertação de mestrado, Qualidade em Análises, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015

Head Space-Trap GC-MS method development and validation for the analysis of volatile organic compounds in water samples

Dissertação de Mestrado, Qualidade em Análises, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015