The Spatial Convergence of Knowledge in Portugal

Human resources are an essential element in territorial development. When these are characterized by a high level of training, they also enhance a number of effects in fundamental areas of binomial territorial-social cohesion. In this respect, the existence of higher education institutions throughout the territory allows the spread of human resources’ qualification but, by itself, does not guarantee the retention of these resources in different regions. Thus, the objective of this paper is to undertake a spatial analysis of convergence of knowledge through studying the evolution of the percentage of population with higher education in the periods elapsed between the last three censuses in Portugal. Although that percentage has risen appreciably, the convergence is shown to be (very) insignificant.

Haemocompatibility of iron oxide nanoparticles synthesized for theranostic applications: a high-sensitivity microfluidic tool

The poor heating efficiency of the most reported magnetic nanoparticles (MNPs), allied to the lack of comprehensive biocompatibility and haemodynamic studies, hampers the spread of multifunctional nanoparticles as the next generation of therapeutic bio-agents in medicine. The present work reports the synthesis and characterization, with special focus on biological/toxicological compatibility, of superparamagnetic nanoparticles with diameter around 18 nm, suitable for theranostic applications (i.e. simultaneous diagnosis and therapy of cancer). Envisioning more insights into the complex nanoparticle-red blood cells (RBCs) membrane interaction, the deformability of the human RBCs in contact with magnetic nanoparticles (MNPs) was assessed for the first time with a microfluidic extensional approach, and used as an indicator of haematological disorders in comparison with a conventional haematological test, i.e. the haemolysis analysis. Microfluidic results highlight the potential of this microfluidic tool over traditional haemolysis analysis, by detecting small increments in the rigidity of the blood cells, when traditional haemotoxicology analysis showed no significant alteration (haemolysis rates lower than 2 %). The detected rigidity has been predicted to be due to the wrapping of small MNPs by the bilayer membrane of the RBCs, which is directly related to MNPs size, shape and composition. The proposed microfluidic tool adds a new dimension into the field of nanomedicine, allowing to be applied as a highsensitivity technique capable of bringing a better understanding of the biological impact of nanoparticles developed for clinical applications.

Tapes, Transgression and Mundanity: the participatory engenderment of death metal and grindcore

Since its origins in the early 1980s, the popular rise of extreme metal throughout the globe has been phenomenal. The emergence of extreme metal's most sonically transgressive subgenres of death metal and grindcore between the mid 1980s and the early 1990s, however, was not an easy one. Indeed, during this period, the only way for globally dispersed extreme metal fans and unsigned extreme metal bands to stay musically connected was via the underground practice of tape-trading. The aim of this study is to illuminate the impact of tape-trading upon the global spread of extreme metal. The study will situate the historical context of extreme metal tape-trading by exploring how it emerged, and why it was necessary in the first place. Utilising the concept of 'extreme metal scene', the study will focus on the central scenic discourse of transgression and explore how this was negotiated into the mundane scenic practice of tape-trading. In relation to this, and utilising the concept of participatory culture, the study will further explore how the music arose and spread throughout the globe via the socially networked practice of both musician and non-musician tape-traders in relation to the tape cassette technology itself. Ethnographic interviews were undertaken with both types of traders in order to gain a deeper understanding of the phenomenon in question. The research concludes that the tape-traders were able to challenge the status quo of record company gatekeepers, by facilitating the engenderment and global distribution (including the later commercial distribution) of death metal and grindcore. Such powerfully affective music via its continual global spread, offers as it did for the original tape-traders, a pleasurable and empowering communal/personal space for disempowered people throughout the globe. Further research into extreme metal tape-trading would require deeper exploration into other extreme metal subgenres, especially black metal, tape-traders situated outside of North America and Europe, women tape-traders as well as exploration of the phenomenon after the early 1990s.

Molecular characterization of extended-spectrum cephalosporin-resistance in Escherichia coli in pigs on-farm and from clinical cases throughout Quebec, Canada during 16 years

Le développement de la multirésistance chez Escherichia coli est un problème important en médecine animale et humaine. En outre, l’émergence et la diffusion des déterminants de résistance aux céphalosporines à larges spectres de troisième génération (ESCs) parmi les isolats, incluant des céphalosporines essentielles en médecine humaine (ex. ceftriaxone et ceftiofur), est un problème majeur de santé publique. Cette thèse visait trois objectifs. D’abord étudier la dynamique de la résistance aux antimicrobiens (AMR) ainsi que la virulence et les profils génétiques de la AMR des E. coli isolées de porcs recevant une nourriture post-sevrage supplémentée avec de la chlortétracycline et de la pénicilline G, et, accessoirement, évaluer les effets d'additifs alimentaires sur cette dynamique en prenant pour exemple d'étude un minéral argileux, la clinoptilolite, étant donné son possible lien avec le gène blaCMY-2 qui confère la résistance au ceftiofur. L'objectif suivant était d'investiguer les mécanismes menant à une augmentation de la prévalence du gène blaCMY-2 chez les porcs qui reçoivent de la nourriture médicamentée et qui n'ont pas été exposés au ceftiofur Ici encore,nous avons examiné les effets d’un supplément alimentaire avec un minéral argileux sur ce phénomène. Enfin, notre dernier objectif était d’étudier, dans le temps, les génotypes des isolats cliniques d'E. coli résistant au ceftiofur, isolés de porcs malades au Québec à partir du moment où la résistance au ceftiofur a été rapportée, soit de 1997 jusqu'à 2012. Dans l'étude initiale, la prévalence de la résistance à 10 agents antimicrobiens, incluant le ceftiofur, s’accroît avec le temps chez les E.coli isolées de porcelets sevrés. Une augmentation tardive de la fréquence du gène blaCMY-2, encodant pour la résistance au ceftiofur, et la présence des gènes de virulence iucD et tsh a été observée chez les isolats. La nourriture supplémentée avec de la clinoptilolite a été associée à une augmentation rapide mais, par la suite, à une diminution de la fréquence des gènes blaCMY-2 dans les isolats. En parallèle, une augmentation tardive dans la fréquence des gènes blaCMY-2 et des gènes de virulence iucD et tsh a été observée dans les isolats des porcs contrôles, étant significativement plus élevé que dans les porcs ayant reçu l'additif au jour 28. La diversité, au sein des E. coli positives pour blaCMY-2 , a été observée au regard des profils AMR. Certaines lignées clonales d'E.coli sont devenues prédominantes avec le temps. La lignée clonale du phylotype A prédominait dans le groupe supplémenté, alors que les lignées clonales du phylotype B1, qui possèdent souvent le gène de virulence iucD associé aux ExPEC, prédominaient dans le groupe contrôle. Les plasmides d'incompatibilité (Inc) des groupes, I1, A/C, et ColE, porteurs de blaCMY-2, ont été observés dans les transformants. Parmi les souches cliniques d'E.coli ESC-résistantes, isolées de porcs malades au Québec de 1997 à 2012, blaCMY-2 était le gène codant pour une β-lactamase le plus fréquemment détecté; suivi par blaTEM et blaCTX-M,. De plus, les analyses clonales montrent une grande diversité génétique. Par contre, des isolats d'E. coli avec des profils PFGE identiques ont été retrouvés dans de multiples fermes la même année mais aussi dans des années différentes. La résistance à la gentamicine, kanamycine, chloramphenicol, et la fréquence de blaTEM et de IncA/C diminuent significativement au cour de la période étudiée, alors que la fréquence de IncI1 et de la multirésistance à sept catégories d'agents antimicrobiens augmente significativement avec le temps. L'émergence d'isolats d'E. coli positifs pour blaCTX-M, une β-lactamase à large spectre et produisant des ESBL, a été observée en 2011 et 2012 à partir de lignées clonales distinctes et chez de nombreuses fermes. Ces résultats, mis ensemble, apportent des précisions sur la dissémination de la résistance au ceftiofur dans les E. coli isolées de porcs. Au sein des échantillons prélevés chez les porcs sevrés recevant l'alimentation médicamentée sur une ferme, et pour laquelle une augmentation de la résistance au ceftiofur a été observée, les données révèlent que les souches d'E. coli positives pour blaCMY-2 et résistantes aux ESCs appartenaient à plusieurs lignées clonales différentes arborant divers profils AMR. Le gène blaCMY-2 se répand à la fois horizontalement et clonalement chez ces E. coli. L'ajout de clinoptilotite à la nourriture et le temps après le sevrage influencent la clonalité et la prévalence du gène blaCMY-2 dans les E. coli. Durant les 16 années d'étude, plusieurs lignées clonales différentes ont été observées parmi les souches d'E. coli résistantes au ceftiofur isolées de porc malades de fermes québécoises, bien qu’aucune lignée n'était persistante ou prédominante pendant l'étude. Les résultats suggèrent aussi que le gène blaCMY-2 s'est répandu à la fois horizontalement et clonalement au sein des fermes. De plus, blaCMY-2 est le gène majeur des β-lactamases chez ces isolats. À partir de 2011, nous rapportons l'émergence du gène blaCTX-M dans des lignées génétiques distinctes.

An agent-based simulation of in-store customer experiences

Agent-based modelling and simulation offers a new and exciting way of understanding the world of work. In this paper we describe the development of an agent-based simulation model, designed to help to understand the relationship between human resource management practices and retail productivity. We report on the current development of our simulation model which includes new features concerning the evolution of customers over time. To test some of these features we have conducted a series of experiments dealing with customer pool sizes, standard and noise reduction modes, and the spread of the word of mouth. Our multidisciplinary research team draws upon expertise from work psychologists and computer scientists. Despite the fact we are working within a relatively novel and complex domain, it is clear that intelligent agents offer potential for fostering sustainable organisational capabilities in the future.

Simulating customer experience and word-of-mouth in retail: a case study

Agents offer a new and exciting way of understanding the world of work. In this paper we describe the development of agent-based simulation models, designed to help to understand the relationship between people management practices and retail performance. We report on the current development of our simulation models which includes new features concerning the evolution of customers over time. To test the features we have conducted a series of experiments dealing with customer pool sizes, standard and noise reduction modes, and the spread of customers’ word of mouth. To validate and evaluate our model, we introduce new performance measure specific to retail operations. We show that by varying different parameters in our model we can simulate a range of customer experiences leading to significant differences in performance measures. Ultimately, we are interested in better understanding the impact of changes in staff behavior due to changes in store management practices. Our multi-disciplinary research team draws upon expertise from work psychologists and computer scientists. Despite the fact we are working within a relatively novel and complex domain, it is clear that intelligent agents offer potential for fostering sustainable organizational capabilities in the future.

Analysis of a stochastic SIR epidemic on a random network incorporating household structure

This paper is concerned with a stochastic SIR (susceptible-infective-removed) model for the spread of an epidemic amongst a population of individuals, with a random network of social contacts, that is also partitioned into households. The behaviour of the model as the population size tends to infinity in an appropriate fashion is investigated. A threshold parameter which determines whether or not an epidemic with few initial infectives can become established and lead to a major outbreak is obtained, as are the probability that a major outbreak occurs and the expected proportion of the population that are ultimately infected by such an outbreak, together with methods for calculating these quantities. Monte Carlo simulations demonstrate that these asymptotic quantities accurately reflect the behaviour of finite populations, even for only moderately sized finite populations. The model is compared and contrasted with related models previously studied in the literature. The effects of the amount of clustering present in the overall population structure and the infectious period distribution on the outcomes of the model are also explored.

Spatial and temporal country-wide survey of temephos resistance in Brazilian populations of Aedes aegypti

The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito ( Aedes aegypti ) in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in Brazil for the last 12 years using discriminating temephos concentrations and the bioassay protocols of the World Health Organization. The mortality results obtained were subjected to spatial analysis for distance interpolation using semi-variance models to generate maps that depict the spread of temephos resistance in Brazil since 1999. The problem has been expanding. Since 2002-2003, approximately half the country has exhibited mosquito populations resistant to temephos. The frequency of temephos resistance and, likely, control failures, which start when the insecticide mortality level drops below 80%, has increased even further since 2004. Few parts of Brazil are able to achieve the target 80% efficacy threshold by 2010/2011, resulting in a significant risk of control failure by temephos in most of the country. The widespread resistance to temephos in Brazilian Ae. aegypti populations greatly compromise effective mosquito control efforts using this insecticide and indicates the urgent need to identify alternative insecticides aided by the preventive elimination of potential mosquito breeding sites.

Phylogenetic analyses of chikungunya virus among travelers in Rio de Janeiro, Brazil, 2014-2015

Chikungunya virus (CHIKV) is a mosquito-borne pathogen that emerged in Brazil by late 2014. In the country, two CHIKV foci characterized by the East/Central/South Africa and Asian genotypes, were established in North and Northeast regions. We characterized, by phylogenetic analyses of full and partial genomes, CHIKV from Rio de Janeiro state (2014-2015). These CHIKV strains belong to the Asian genotype, which is the determinant of the current Northern Brazilian focus, even though the genome sequence presents particular single nucleotide variations. This study provides the first genetic characterisation of CHIKV in Rio de Janeiro and highlights the potential impact of human mobility in the spread of an arthropod-borne virus.

Morphological traits of surveillant/activated microglia during an experimentally induced acute neuroinflammatory process

Several studies show that morphological changes of microglia over the course of inflammation are tightly coupled to function. However the progressive transformation into activated microglia is poorly characterized. AIMS: This study aimed to establish a spatiotemporal correlation between quantifiable morphological parameters of microglia and the spread of an acute ventricular inflammatory process. METHODS: Inflammation was induced by a single injection of the enzyme neuraminidase within the lateral ventricle of rats. Animals were sacrificed 2, 4 and 12 hours after injection. Coronal slices were immunostained with Iba1 to label microglia and with IL1β to delimit the spread of inflammation. Digital images were obtained by scanning the labelled sections. Single microglia images were randomly selected from periventricular areas of caudate putamen, hippocampus and hypothalamus. FracLac for ImageJ software was used to measure the following morphological parameters: fractal dimension, lacunarity, area, perimeter and density. RESULTS: Significant differences were found in fractal dimension, lacunarity, perimeter and density of microglia cells of neuraminidase injected rats compared to sham animals. However no differences were found in the parameter “area”. In hipoccampus there was a delay in the significant change of the measured parameters. These morphological changes correlated with IL1β-expression in the same areas. CONCLUSIONS: Ventricular inflammation induced by neuraminidase provokes quantifiable morphological changes in microglia restricted to areas labelled with IL1β. Morphological parameters of microglia such as fractal dimension, lacunarity, perimeter and density are sensitive and valuable tools to quantify activation. However, the extensively used parameter “area” did not change upon microglia activation.

Design and synthesis of novel quinolones directed to the Plasmodium falciparum bc1 protein complex

Tese de Doutoramento, Química, Especialização em Química Orgânica, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2016

Theoretical investigation of intra- and inter-cellular spatiotemporal calcium patterns in microcirculation

Microcirculatory vessels are lined by endothelial cells (ECs) which are surrounded by a single or multiple layer of smooth muscle cells (SMCs). Spontaneous and agonist induced spatiotemporal calcium (Ca2+) events are generated in ECs and SMCs, and regulated by complex bi-directional signaling between the two layers which ultimately determines the vessel tone. The contractile state of microcirculatory vessels is an important factor in the determination of vascular resistance, blood flow and blood pressure. This dissertation presents theoretical insights into some of the important and currently unresolved phenomena in microvascular tone regulation. Compartmental and continuum models of isolated EC and SMC, coupled EC-SMC and a multi-cellular vessel segment with deterministic and stochastic descriptions of the cellular components were developed, and the intra- and inter-cellular spatiotemporal Ca2+ mobilization was examined.^ Coupled EC-SMC model simulations captured the experimentally observed localized subcellular EC Ca2+ events arising from the opening of EC transient receptor vanilloid 4 (TRPV4) channels and inositol triphosphate receptors (IP3Rs). These localized EC Ca2+ events result in endothelium-derived hyperpolarization (EDH) and Nitric Oxide (NO) production which transmit to the adjacent SMCs to ultimately result in vasodilation. The model examined the effect of heterogeneous distribution of cellular components and channel gating kinetics in determination of the amplitude and spread of the Ca2+ events. The simulations suggested the necessity of co-localization of certain cellular components for modulation of EDH and NO responses. Isolated EC and SMC models captured intracellular Ca2+ wave like activity and predicted the necessity of non-uniform distribution of cellular components for the generation of Ca2+ waves. The simulations also suggested the role of membrane potential dynamics in regulating Ca2+ wave velocity. The multi-cellular vessel segment model examined the underlying mechanisms for the intercellular synchronization of spontaneous oscillatory Ca2+ waves in individual SMC. ^ From local subcellular events to integrated macro-scale behavior at the vessel level, the developed multi-scale models captured basic features of vascular Ca2+ signaling and provide insights for their physiological relevance. The models provide a theoretical framework for assisting investigations on the regulation of vascular tone in health and disease.^

Clustering of tau-immunoreactive pathology in chronic traumatic encephalopathy

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disorder which may result from repetitive brain injury. A variety of tau-immunoreactive pathologies are present, including neurofibrillary tangles (NFT), neuropil threads (NT), dot-like grains (DLG), astrocytic tangles (AT), and occasional neuritic plaques (NP). In tauopathies, cellular inclusions in the cortex are clustered within specific laminae, the clusters being regularly distributed parallel to the pia mater. To determine whether a similar spatial pattern is present in CTE, clustering of the tau-immunoreactive pathology was studied in the cortex, hippocampus, and dentate gyrus in 11 cases of CTE and 7 cases of Alzheimer’s disease neuropathologic change (ADNC) without CTE. In CTE: (1) all aspects of tau-immunoreactive pathology were clustered and the clusters were frequently regularly distributed parallel to the tissue boundary, (2) clustering was similar in two CTE cases with minimal co-pathology compared with cases with associated ADNC or TDP-43 proteinopathy, (3) in a proportion of cortical gyri, estimated cluster size was similar to that of cell columns of the cortico-cortical pathways, and (4) clusters of the tau-immunoreactive pathology were infrequently spatially correlated with blood vessels. The NFT and NP in ADNC without CTE were less frequently randomly or uniformly distributed and more frequently in defined clusters than in CTE. Hence, the spatial pattern of the tau-immunoreactive pathology observed in CTE is typical of the tauopathies but with some distinct differences compared to ADNC alone. The spread of pathogenic tau along anatomical pathways could be a factor in the pathogenesis of the disease.

Modular framework to assess the risk of African swine fever virus entry into the European Union

BACKGROUND The recent occurrence and spread of African swine fever (ASF) in Eastern Europe is perceived as a serious risk for the pig industry in the European Union (EU). In order to estimate the potential risk of ASF virus (ASFV) entering the EU, several pathways of introduction were previously assessed separately. The present work aimed to integrate five of these assessments (legal imports of pigs, legal imports of products, illegal imports of products, fomites associated with transport and wild boar movements) into a modular tool that facilitates the visualization and comprehension of the relative risk of ASFV introduction into the EU by each analyzed pathway. RESULTS The framework's results indicate that 48% of EU countries are at relatively high risk (risk score 4 or 5 out of 5) for ASFV entry for at least one analyzed pathway. Four of these countries obtained the maximum risk score for one pathway: Bulgaria for legally imported products during the high risk period (HRP); Finland for wild boar; Slovenia and Sweden for legally imported pigs during the HRP. Distribution of risk considerably differed from one pathway to another; for some pathways, the risk was concentrated in a few countries (e.g., transport fomites), whereas other pathways incurred a high risk for 4 or 5 countries (legal pigs, illegal imports and wild boar). CONCLUSIONS The modular framework, developed to estimate the risk of ASFV entry into the EU, is available in a public domain, and is a transparent, easy-to-interpret tool that can be updated and adapted if required. The model's results determine the EU countries at higher risk for each ASFV introduction route, and provide a useful basis to develop a global coordinated program to improve ASFV prevention in the EU.

Large-scale screening of a targeted Enterococcus faecalis mutant library identifies envelope fitness factors

Spread of antibiotic resistance among bacteria responsible for nosocomial and community-acquired infections urges for novel therapeutic or prophylactic targets and for innovative pathogen-specific antibacterial compounds. Major challenges are posed by opportunistic pathogens belonging to the low GC% gram-positive bacteria. Among those, Enterococcus faecalis is a leading cause of hospital-acquired infections associated with life-threatening issues and increased hospital costs. To better understand the molecular properties of enterococci that may be required for virulence, and that may explain the emergence of these bacteria in nosocomial infections, we performed the first large-scale functional analysis of E. faecalis V583, the first vancomycin-resistant isolate from a human bloodstream infection. E. faecalis V583 is within the high-risk clonal complex 2 group, which comprises mostly isolates derived from hospital infections worldwide. We conducted broad-range screenings of candidate genes likely involved in host adaptation (e.g., colonization and/or virulence). For this purpose, a library was constructed of targeted insertion mutations in 177 genes encoding putative surface or stress-response factors. Individual mutants were subsequently tested for their i) resistance to oxidative stress, ii) antibiotic resistance, iii) resistance to opsonophagocytosis, iv) adherence to the human colon carcinoma Caco-2 epithelial cells and v) virulence in a surrogate insect model. Our results identified a number of factors that are involved in the interaction between enterococci and their host environments. Their predicted functions highlight the importance of cell envelope glycopolymers in E. faecalis host adaptation. This study provides a valuable genetic database for understanding the steps leading E. faecalis to opportunistic virulence.