Software transactional memory as a building block for parallel embedded realtime systems

The recent trends of chip architectures with higher number of heterogeneous cores, and non-uniform memory/non-coherent caches, brings renewed attention to the use of Software Transactional Memory (STM) as a fundamental building block for developing parallel applications. Nevertheless, although STM promises to ease concurrent and parallel software development, it relies on the possibility of aborting conflicting transactions to maintain data consistency, which impacts on the responsiveness and timing guarantees required by embedded real-time systems. In these systems, contention delays must be (efficiently) limited so that the response times of tasks executing transactions are upper-bounded and task sets can be feasibly scheduled. In this paper we assess the use of STM in the development of embedded real-time software, defending that the amount of contention can be reduced if read-only transactions access recent consistent data snapshots, progressing in a wait-free manner. We show how the required number of versions of a shared object can be calculated for a set of tasks. We also outline an algorithm to manage conflicts between update transactions that prevents starvation.

Managing contention of software transactional memory in real-time systems

The foreseen evolution of chip architectures to higher number of, heterogeneous, cores, with non-uniform memory and non-coherent caches, brings renewed attention to the use of Software Transactional Memory (STM) as an alternative to lock-based synchronisation. However, STM relies on the possibility of aborting conflicting transactions to maintain data consistency, which impacts on the responsiveness and timing guarantees required by real-time systems. In these systems, contention delays must be (efficiently) limited so that the response times of tasks executing transactions are upperbounded and task sets can be feasibly scheduled. In this paper we defend the role of the transaction contention manager to reduce the number of transaction retries and to help the real-time scheduler assuring schedulability. For such purpose, the contention management policy should be aware of on-line scheduling information.

Non-preemptive and SRP-based fullypreemptive scheduling of real-time Software Transactional Memory

Recent embedded processor architectures containing multiple heterogeneous cores and non-coherent caches renewed attention to the use of Software Transactional Memory (STM) as a building block for developing parallel applications. STM promises to ease concurrent and parallel software development, but relies on the possibility of abort conflicting transactions to maintain data consistency, which in turns affects the execution time of tasks carrying transactions. Because of this fact the timing behaviour of the task set may not be predictable, thus it is crucial to limit the execution time overheads resulting from aborts. In this paper we formalise a FIFO-based algorithm to order the sequence of commits of concurrent transactions. Then, we propose and evaluate two non-preemptive and one SRP-based fully-preemptive scheduling strategies, in order to avoid transaction starvation.

Planificação de um sistema de informação para a unidade de formação contínua e avançada da Escola Superior de Educação do Instituto Politécnico do Porto

Projecto apresentado ao Instituto Superior de Contabilidade e Administração do Porto para a obtenção do Grau de Mestre em Assessoria de Administração

A Implementação de um sistema de gestão da qualidadena Junta de Freguesia de Gandra

Trabalho de Projeto apresentado ao Instituto Superior de Contabilidade e Administração do Porto para obtenção do grau de Mestre em Auditoria Orientado por: Doutora Alcina Augusta de Sena Portugal Dias

Identity – towards a conceptualization

The development of economical relations increases the interaction between organizations and stakeholders. It is no more acceptable to manage an organization under a transactional perspective where suppliers had a fundamental role. Nowadays organizations are being managed under a relational perspective where relations and relationship management in general have consequences in identity management (Hakansson e Snehota, 1989, 1995). A correct perception and management of identity is necessary to achieve distinctiveness in the competitive environment. This way, identity is influenced by relations with stakeholders in general and particularly with competitors. The ICIG concept states that identity is related with the values of the organization and it helps creating distinctiveness in the competitive environment (Van Riel, Balmer, 1997); Baker and Balmer (1997) state that identity is what the organization is; Suvatjis and de Chernatony (2005) refer that expressing identity is a dynamic process that evolves the use of a management model to face context changes; Kapferer (1991) states that brand identity is the project, the self conception of the brand. After reviewing and confronting literature under the plethora of identities’ concepts and perspectives (He, Balmer, 2007) one can’t find an integrative answer with all the elements that contribute to identity of organizations. The authors are strongly interested to contribute to the elimination of this limitation and to answer to strategic management needs. In a marketing context one can find: - the corporate identity approach that is focused in the distinctive attributes of an organization (Abratt, Balmer, Marwick e Fill, Stuart, Balmer and Gray, Alessandri, Suvatjis and de Chernatony) - the brand identity approach (related with the application of corporate identity studies to brands) - Kapferer, Semprini, Aaker, de Chernatony). Kapferer (1991), one of the most prolific authors in this field was the first author to integrate identity in a brand concept. In his view, identity is an emission concept. This idea is shared also by Aaker (1996). Yet, identity has to be managed in a competitive environment which is constantly changing. After reviewing and confronting literature, authors select concepts that are generally accepted by the investigators in order to design a model to analyze and manage identity: - corporate identity models: personality, image/reputation, culture, philosophy, mission, strategy, structure, communication - some of these concepts derive from identity models and others from identity management models; - brand identity models – Kapferer (1991, 2008) identity prism, witch is basis of literature in this field: culture, physical facet, personality, relationship (between brand and consumer), reflected consumer, consumers` self-concept. After discussion authors decide to include other concept in line with other authors` view: country of origin (Aaker, 1996). A discussion eliminates the twin concepts and the final selection is as follows: personality, image/reputation, culture (including philosophy and mission), strategy, structure, communication, culture, physical facet, relationship (between brand and consumer), reflected consumer, consumers` self-concept and according to authors` reflections “relationships” deriving from competitors` actions in competitive environment. Competitors’ actions and decisions have a stronger influence in the organizations` positioning than any other stakeholder as stated before. This is a work in progress towards a new model in identity analysis and management so an exploratory study will follow inquiring experts on identity in order to evaluate these concepts and correct the theoretical perspectives.

Eficácia do Constraint-Induced Movement Therapy, em utentes com sequelas de Acidente Vascular Encefálico, até 9 meses

O Acidente Vascular Encefálico é uma das principais causas de morte, tornando-se cada vez mais iminente processos de reabilitação que minimizem as sequelas, nomeadamente as limitações do membro superior que dificultam o envolvimento em atividades da vida diária. O Constraint-Induced Movement Therapy, surge como uma abordagem que incrementa o uso do membro superior mais afetado. A presente investigação trata-se de um estudo de casos múltiplos. Pretende-se verificar se existem melhorias na funcionalidade do membro superior mais afetado, analisar em que atividades da vida diária são visíveis melhorias funcionais e compreender se o maior envolvimento nas atividades diárias está diretamente relacionado com a melhoria na capacidade funcional. Pretende-se ainda que os valores obtidos no Wolf Motor Function Test sejam um contributo para a sua validação para a população portuguesa. Utilizou-se um questionário para recolha de dados pessoais e clínicos (amplitudes de movimento, dor e espasticidade); o Wolf Motor Function Test e o Action Research Arm Test para verificar a funcionalidade do membro superior mais afetado; e a Motor Activity Log que avalia o envolvimento em atividades da vida diária. O grupo é constituído por 3 utentes que sofreram um primeiro Acidente Vascular Encefálico até 9 meses de evolução, internados na Santa Casa da Misericórdia de Monção e que cumpriam os critérios de inclusão. O programa foi implementado três horas/dia, durante 10 dias, mantendo a restrição no membro superior menos afetado durante 90% do dia acordado. Como se trata de um estudo de casos múltiplos, analisou-se cada participante individualmente e verificou-se a diferença entre os resultados finais e iniciais para cada uma das variáveis. Os resultados obtidos revelam ganhos na amplitude de movimento, velocidade de execução e capacidade funcional do membro superior mais afetado, nomeadamente nas funções de preensão e pinça da mão, bem como se testemunhou minimização do fenómeno learned nonuse. Verificaram-se ganhos funcionais em todos os participantes nas atividades da vida diária apesar de serem diferentes de participante para participante. Dois participantes afirmaram que voltariam a participar no programa.Conclui-se, assim que a técnica resulta em ganhos funcionais nestes utentes, indicando um caminho alternativo a outras abordagens de reabilitação.

Descoberta de conhecimento em Logs de tentativas de intrusão. Um estudo de caso em Instituições de Ensino Superior

Perante a evolução constante da Internet, a sua utilização é quase obrigatória. Através da web, é possível conferir extractos bancários, fazer compras em países longínquos, pagar serviços sem sair de casa, entre muitos outros. Há inúmeras alternativas de utilização desta rede. Ao se tornar tão útil e próxima das pessoas, estas começaram também a ganhar mais conhecimentos informáticos. Na Internet, estão também publicados vários guias para intrusão ilícita em sistemas, assim como manuais para outras práticas criminosas. Este tipo de informação, aliado à crescente capacidade informática do utilizador, teve como resultado uma alteração nos paradigmas de segurança informática actual. Actualmente, em segurança informática a preocupação com o hardware é menor, sendo o principal objectivo a salvaguarda dos dados e continuidade dos serviços. Isto deve-se fundamentalmente à dependência das organizações nos seus dados digitais e, cada vez mais, dos serviços que disponibilizam online. Dada a mudança dos perigos e do que se pretende proteger, também os mecanismos de segurança devem ser alterados. Torna-se necessário conhecer o atacante, podendo prever o que o motiva e o que pretende atacar. Neste contexto, propôs-se a implementação de sistemas de registo de tentativas de acesso ilícitas em cinco instituições de ensino superior e posterior análise da informação recolhida com auxílio de técnicas de data mining (mineração de dados). Esta solução é pouco utilizada com este intuito em investigação, pelo que foi necessário procurar analogias com outras áreas de aplicação para recolher documentação relevante para a sua implementação. A solução resultante revelou-se eficaz, tendo levado ao desenvolvimento de uma aplicação de fusão de logs das aplicações Honeyd e Snort (responsável também pelo seu tratamento, preparação e disponibilização num ficheiro Comma Separated Values (CSV), acrescentando conhecimento sobre o que se pode obter estatisticamente e revelando características úteis e previamente desconhecidas dos atacantes. Este conhecimento pode ser utilizado por um administrador de sistemas para melhorar o desempenho dos seus mecanismos de segurança, tais como firewalls e Intrusion Detection Systems (IDS).

Molecularly-imprinted materials for potentiometric transduction: application to the antibiotic enrofloxacin

Enrofloxacin (ENR) is an antimicrobial used both in humans and in food producing species. Its control is required in farmed species and their surroundings in order to reduce the prevalence of antibiotic resistant bacteria. Thus, a new biomimetic sensor enrofloxacin is presented. An artificial host was imprinted in specific polymers. These were dispersed in 2-nitrophenyloctyl ether and entrapped in a poly(vinyl chloride) matrix. The potentiometric sensors exhibited a near-Nernstian response. Slopes expressing mVΔlog([ENR]/M) varied within 48–63. The detection limits ranged from 0.28 to 1.01 µg mL 1. Sensors were independent from the pH of test solutions within 4–7. Good selectivity was observed toward potassium, calcium, barium, magnesium, glycine, ascorbic acid, creatinine, norfloxacin, ciprofloxacin, and tetracycline. In flowing media, the biomimetic sensors presented good reproducibility (RSD of ±0.7%), fast response, good sensitivity (47 mV/Dlog([ENR]/ M), wide linear range (1.0×10-5–1.0×10-3 M), low detection limit (0.9 µg mL-1), and a stable baseline for a 5×10-2 M acetate buffer (pH 4.7) carrier. The sensors were used to analyze fish samples. The method offered the advantages of simplicity, accuracy, and automation feasibility. The sensing membrane may contribute to the development of small devices allowing in vivo measurements of enrofloxacin or parent-drugs.

The predominance of M2-polarized macrophages in the stroma of low-hypoxic bladder tumors is associated with BCG immunotherapy failure

OBJECTIVE: Bacillus Calmette-Guérin (BCG) immunotherapy is the gold standard treatment for superficial bladder tumors with intermediate/high risk of recurrence or progression. However, approximately 30% of patients fail to respond to the treatment. Effective BCG therapy needs precise activation of the type 1 helper cells immune pathway. Tumor-associated macrophages (TAMs) often assume an immunoregulatory M2 phenotype and may directly interfere with the BCG-induced antitumor immune response. Thus, we aim to clarify the influence of TAMs, in particular of the M2 phenotype in stroma and tumor areas, in BCG treatment outcome. PATIENTS AND METHODS: The study included 99 patients with bladder cancer treated with BCG. Tumors resected before treatment were evaluated using immunohistochemistry for CD68 and CD163 antigens, which identify a lineage macrophage marker and a M2-polarized specific cell surface receptor, respectively. CD68+ and CD163+ macrophages were evaluated within the stroma and tumor areas, and high density of infiltrating cells spots were selected for counting. Hypoxia, an event known to modulate macrophage phenotype, was also assessed through hypoxia induced factor (HIF)-1α expression. RESULTS: Patients in whom BCG failed had high stroma-predominant CD163+ macrophage counts (high stroma but low tumor CD163+ macrophages counts) when compared with the ones with a successful treatment (71% vs. 47%, P = 0.017). Furthermore, patients presenting this phenotype showed decreased recurrence-free survival (log rank, P = 0.008) and a clear 2-fold increased risk of BCG treatment failure was observed in univariate analysis (hazard ratio = 2.343; 95% CI: 1.197-4.587; P = 0.013). Even when adjusted for potential confounders, such as age and therapeutic scheme, multivariate analysis revealed 2.6-fold increased risk of recurrence (hazard ratio = 2.627; 95% CI: 1.340-5.150; P = 0.005). High stroma-predominant CD163+ macrophage counts were also associated with low expression of HIF-1α in tumor areas, whereas high counts of CD163+ in the tumor presented high expression of HIF-1α in tumor nests. CONCLUSIONS: TAMs evaluation using CD163 is a good indicator of BCG treatment failure. Moreover, elevated infiltration of CD163+ macrophages, predominantly in stroma areas but not in the tumor, may be a useful indicator of BCG treatment outcome, possibly owing to its immunosuppressive phenotype.

Revisiting transactions in Ada

Classical lock-based concurrency control does not scale with current and foreseen multi-core architectures, opening space for alternative concurrency control mechanisms. The concept of transactions executing concurrently in isolation with an underlying mechanism maintaining a consistent system state was already explored in fault-tolerant and distributed systems, and is currently being explored by transactional memory, this time being used to manage concurrent memory access. In this paper we discuss the use of Software Transactional Memory (STM), and how Ada can provide support for it. Furthermore, we draft a general programming interface to transactional memory, supporting future implementations of STM oriented to real-time systems.

Soluções para monitorização, salvaguarda de configurações e segurança na rede do banco BNP Paribas Personal Finance S. A. em Vila Nova De Gaia

Mestrado em Engenharia Electrotécnica e de Computadores - Área de Especialização de Telecomunicações

Electrochemical immunosensor for the analysis of the breast cancer biomarker HER2 ECD

Human epidermal growth factor receptor 2 (HER2) is a breast cancer biomarker that plays a major role in promoting breast cancer cell proliferation and malignant growth. The extracellular domain (ECD) of HER2 can be shed into the blood stream and its concentration is measurable in the serum fraction of blood. In this work an electrochemical immunosensor for the analysis of HER2 ECD in human serum samples was developed. To achieve this goal a screen-printed carbon electrode, modified with gold nanoparticles, was used as transducer surface. A sandwich immunoassay, using two monoclonal antibodies, was employed and the detection of the antibody–antigen interaction was performed through the analysis of an enzymatic reaction product by linear sweep voltammetry. Using the optimized experimental conditions the calibration curve (ip vs. log[HER2 ECD]) was established between 15 and 100 ng/mL and a limit of detection (LOD) of 4.4 ng/mL was achieved. These results indicate that the developed immunosensor could be a promising tool in breast cancer diagnostics, patient follow-up and monitoring of metastatic breast cancer since it allows quantification in a useful concentration range and has an LOD below the established cut-off value (15 ng/mL).

Marketing experiencial, emoções, satisfação e lealdade

O marketing transacional apresenta-se nos dias de hoje insuficiente para fazer face às exigências de um consumidor mais participativo, seletivo e crítico. No mercado global, industrializado e em constante evolução tecnológica, é, cada vez mais, difícil obter um grau de diferenciação assente apenas nos benefícios funcionais e racionais. O marketing transacional evoluiu para o marketing relacional, constituindo o cliente o centro do processo de trocas. A economia das experiências alterou a forma como as marcas trabalham o mercado, introduzindo o conceito de experiências, o que por sua vez conceptualizou o marketing experiencial, orientado para a gestão da experiência do cliente, transformando o ato de consumo em algo memorável, cheio de estímulos sensoriais e emocionais, convertendo-se, por vezes, no próprio produto, seja ele de âmbito industrial, desportivo ou mesmo cultural. Este grau de envolvimento do cliente com a marca é elemento gerador de emoção, de satisfação, de lealdade e de valor. Este trabalho pretendeu analisar a importância e os componentes estimuladores do marketing experiencial e a sua relação com as emoções, satisfação e a lealdade dos consumidores no evento cultural “Serralves em festa 2013”. Para tal, utilizamos uma metodologia de investigação quantitativa, com recurso a análise de equações estruturais, suportada por uma pesquisa teórica. O estudo empírico realizado, baseado num inquérito por questionário, possibilitou obter uma amostra de 264 respostas válidas. Após a validação e melhoria das escalas de medida dos conceitos, os resultados destas e do modelo estrutural demonstraram valores adequados. Estudaram-se e comprovaram-se as relações previstas nas hipóteses, nomeadamente, a relação positiva do impacto das experiências no comportamento do consumidor, designadamente, na sua emoção e satisfação e o impacto destas na sua lealdade. Entre as variáveis estudadas foram obtidos interessantes níveis de correlação e capacidades preditivas.

Multifunctional Biosensor Based on Localized Surface Plasmon Resonance for Monitoring Small Molecule–Protein Interaction

We report an optical sensor based on localized surface plasmon resonance (LSPR) to study small-molecule protein interaction combining high sensitivity refractive index sensing for quantitative binding information and subsequent conformation-sensitive plasmon-activated circular dichroism spectroscopy. The interaction of α-amylase and a small-size molecule (PGG, pentagalloyl glucose) was log concentration-dependent from 0.5 to 154 μM. In situ tests were additionally successfully applied to the analysis of real wine samples. These studies demonstrate that LSPR sensors to monitor small molecule–protein interactions in real time and in situ, which is a great advance within technological platforms for drug discovery.