Repositório RCAAP

Along side with the use of cloud-based services, infrastructure and storage, the use of application logs in business critical applications is a standard practice nowadays. Such application logs must be stored in an accessible manner in order to used whenever needed. The debugging of these applications is a common situation where such access is required. Frequently, part of the information contained in logs records is sensitive. This work proposes a new approach of storing critical logs in a cloud-based storage recurring to searchable encryption, inverted indexing and hash chaining techniques to achieve, in a unified way, the needed privacy, integrity and authenticity while maintaining server side searching capabilities by the logs owner. The designed search algorithm enables conjunctive keywords queries plus a fine-grained search supported by field searching and nested queries, which are essential in the referred use case. To the best of our knowledge, the proposed solution is also the first to introduce a query language that enables complex conjunctive keywords and a fine-grained search backed by field searching and sub queries.

Tendo em conta a envolvente socio económica atual e o seu impacto sobre a classe social dos seniores, este estudo foca a sua atenção no contributo do empreendedorismo social para o desenvolvimento de projetos de inovação social capazes de responder às necessidades da população envelhecida. Um dos objetivos deste trabalho assenta na perceção das alterações demográficas e na problemática do envelhecimento, pelo que pretendemos perceber quais as respostas sociais existentes e de que modo respondem às necessidades e potencialidades da sociedade em constante mudança. A consciência para a importância de encontrar soluções inovadoras para a nova população envelhecida, conduz a um estudo de caso mais pormenorizado – SENIOR COHOUSING, conceito dissecado e explorado em diferentes vertentes com a finalidade de legitimar a aprovação deste modelo habitacional no seio das respostas sociais adequadas. Validando toda a componente teórica que sustenta a base deste estudo, realizamos uma investigação de cariz qualitativo, onde o grande foco foi a HAC.ORA Portugal | senior cohousing association, associação influente nesta área de intervenção, e uma intensa abordagem na primeira conferência internacional “Cohousing em Portugal | Viver Sustentável”, pelos mesmos promovida. A análise dos conteúdos foi realizada tendo como suporte o software Nvivo 12 que auxilia na organização e projeção das várias áreas em estudo.

A presente dissertação tem como objetivo explorar o campo da infografia multimédia presente na imprensa digital. Devido à incorporação de novas tecnologias e de diferentes tendências visuais, verificam-se mudanças substanciais nos modelos consolidados de design de jornais que originaram um crescimento na importância da imagem que o jornal tem na web. Atualmente, um dos principais desafios do jornalismo é a adaptação do conteúdo jornalístico a um panorama tecnológico em constante estado de inovação. Surge então a necessidade de arranjar novas formas de publicar notícias. É aqui que a infografia multimédia ganha relevo, sendo o seu objetivo proporcionar uma nova experiência aos leitores, onde eles próprios podem ter o poder de explorar e/ou interagir com a narrativa. Em suma, o documento procura através do estudo de casos, promover uma análise aos elementos e definições associadas à infografia multimédia, resultando em três modelos de análise e classificação.

Hoje em dia, a internet é um dos meios mais rápidos de divulgação de informação e de grande influência, onde a presença digital é uma necessidade para qualquer organização que pretenda crescer, otimizar as suas receitas e conquistar o público alvo. É fundamental apresentar ao cliente uma imagem forte, confiável e sólida do produto, com conteúdos de qualidade e de forma adequada. No desenvolvimento de um website é essencial ter em consideração os fatores que podem ditar o sucesso, ou fracasso, deste. Assim, é importante definir aquilo que é necessário ter em conta, com o objetivo de proporcionar a melhor experiência possível para o utilizador e, caso se aplique, aumentar as receitas da organização. Os utilizadores são o foco principal no momento de elaboração de um produto, é importante pensar que, satisfazer um cliente pode fazê-lo fiel e este por consequência poderá atrair outros. Portanto, atender às necessidades deste e satisfazê-las é um dever para qualquer organização. O desenvolvimento de um website aliado ao marketing digital, permite construir a melhor solução possível, que ajudará a atender as necessidades do cliente e organizacionais. Estas, permitem o melhoramento constante do produto tendo em conta a usabilidade, desempenho e consequentemente o aumento do número de conversões e boa experiência de utilização. Assim pretende-se comprovar, com este estudo, que o uso de técnicas de desenvolvimento web e marketing digital têm um impacto significativo na organização. Para isso será construída um novo website para a Sweet & Taste, com a intenção de criar um produto que permite aumentar as suas conversões. Para atingir os objetivos mencionados, foi necessário realizar um estudo às várias vertentes teóricas e práticas de desenvolvimento web e marketing digital. A realização da análise de valor permitiu aferir o valor que o produto representa para os seus clientes, bem como avaliação da melhor solução a implementar. Esta dissertação também apresenta uma forma de como os conteúdos de um website devem ser organizados, e quais os processos para a obtenção de dados estatísticos de forma a obter melhores resultados futuramente. Por fim, a experimentação realizada atingiu os objetivos pretendidos, tendo conseguido atingir, na maioria dos indicadores de qualidade, valores superiores a 90%.

This paper describes the design and development of a Smart Companion Pillow, named bGuard, designed by a multinational and multidisciplinary team enrolled in the European Project Semester (EPS) at Instituto Superior de Engenharia do Porto (ISEP) in the spring of 2019. Nowadays, parents spend most of the day at work and become naturally worried about the well-being of their young children, specially babies. The aim of bGuard is to provide a 24-hour remotely accessible baby monitoring service, contributing to reduce parenting stress. The team, based on the survey of related products, as well as on marketing, sustainability, ethics and deontology analyses, developed a remotely interactive Smart Companion Pillow to monitor the baby’s health and room air quality. The collected data, once it is saved on an Internet of Things (IoT) platform, becomes remotely accessible. The bGuard pillow, thanks to its shape, reduces the risk of the baby rolling from back to tummy, lowering the risk of Sudden Infant Death Syndrome (SIDS).

Ocean exploration and monitoring with autonomous platforms can provide researchers and decision makers with valuable data, trends and insights into the largest ecosystem on Earth. Regardless of the recognition of the importance of such platforms in this scenario, their design and development remains an open challenge. In particular, energy efficiency, control and robustness are major concerns with implications in terms of autonomy and sustainability. Wingsails allow autonomous boats to navigate with increased autonomy, due to lower power consumption, and greater robustness, due to simpler control. Within the scope of a project that addresses the design, development and deployment of a rigid wing autonomous sailboat to perform long term missions in the ocean, this paper summarises the general principles for airfoil selection and wingsail design in robotic sailing, and are given some insights on how these aspects influence the autonomous sailboat being developed by the authors.

Engineering education addresses the development of professional competencies in undergraduates. In this context, the core set of professional competencies includes critical thinking and problem solving, effective communication, collaboration and team building, and creativity and innovation—also known as the four Cs—as well as socio-professional ethics and sustainable development—referred in this paper as the two Ss. While the four Cs were identified by the associates of the American Management Association based on the needs of the society, professional associations, and businesses; this paper proposes the two S extension to ensure that future engineers contribute to the well-being of individuals and the preservation of life on Earth. It proposes a tangible framework—the 4C2S—and an application method to analyse the contributions made by engineering capstone programmes to the development of these core competencies in future engineering professionals. The method is applied to an engineering capstone programme—the European Project Semester (EPS) offered by the Instituto Superior de Engenharia do Porto (ISEP)—and a specific project case—EPS@ISEP Pet Tracker project developed in 2013, constituting, in addition, a road map for the application of the 4C2S framework to engineering capstone programmes. The results show that EPS@ISEP complies with the 4C2S framework.

Contribution: An analysis of the extent to which sustainability is present in the syllabi, project briefs, report templates, and student final reports of the three Iberian European project semester (EPS) providers, over a five-year period. Background: EPS is a one-semester capstone project framework that adopts project-based learning and multicultural, multidisciplinary teamwork. Educating engineers for sustainable development requires fostering critical and ethical thinking and a desire for equity, solidarity and preservation of natural resources, and cultural and genetic diversity. Existing engineering capstone design programs emphasize solving real world problems, hands-on training, and soft skills, but few focus on sustainability aspects of engineering design. The three Iberian EPS providers adopt project-based learning and teamwork methodologies, promoting the development of transversal skills and addressing sustainability in a multicultural and multidisciplinary background. Intended Outcomes: To show that the three Iberian EPS providers follow these recommendations and contribute to raising students' awareness of sustainable development. Application Design: The proposed sustainability learning assessment method collects evidence from syllabi, project briefs, report templates, and final reports to extract faculty and student perspectives. The sustainability-related terms collected were processed into word cloud format, allowing a simple and intuitive interpretation of students' understanding of sustainability, and in co-occurrence network format, to understand if sustainability has a pervasive or confined presence within the reports. Findings: Iberian EPS faculty and students are aware of the social, economic, and environmental impact of their projects, in terms of quality of life, social responsibility, the use of resources, and environmentally friendly technology.

The design, development and deployment of autonomous sustainable ocean platforms for exploration and monitoring can provide researchers and decision makers with valuable data, trends and insights into the largest ecosystem on Earth. Although these outcomes can be used to prevent, identify and minimise problems, as well as to drive multiple market sectors, the design and development of such platforms remains an open challenge. In particular, energy efficiency, control and robustness are major concerns with implications for autonomy and sustainability. Rigid wingsails allow autonomous boats to navigate with increased autonomy due to lower power consumption and increased robustness as a result of mechanically simpler control compared to traditional sails. These platforms are currently the subject of deep interest, but several important research problems remain open. In order to foster dissemination and identify future trends, this paper presents a survey of the latest developments in the field of rigid wing sailboats, describing the main academic and commercial solutions both in terms of hardware and software.

Considerando o carácter breve do depoimento solicitado, este organiza-se em tópicos, apresentados de forma propositadamente sumária e organizados em torno de duas preocupações essenciais: estabelecer as circunstâncias do desenvolvimento actual do campo da educação e formação de adultos; enunciar alguns desafios que este enfrenta para que se possa promover o direito dos adultos à educação.

This paper presents an overview on how the European Project Semester capstone programme offered by the Instituto Superior de Engenharia do Porto (EPS@ISEP) fosters learning by challenging engineering, business and product development undergraduates to address sustainability issues afflicting cities and communities nowadays. This will be done by analysing the reports and the learning journey of three multicultural and multidisciplinary EPS@ISEP teams during the design, development and test of a smart billboard, a self-oriented solar mirror and a level monitoring system for waste oil bins. These three projects were conducted within EPS@ISEP, a project-based learning framework dedicated to the development of key engineering skills, namely multidisciplinary teamwork, inter-cultural communication, ethical and sustainability-oriented problem-solving. The involved students contributed, not only, to make cities more inclusive, safe, resilient and sustainable, one of UNESCO’s sustainable development goals, but learnt and practiced together sustainability-driven design, while searching for an innovative solution for a smart city problem. This conclusion is supported by the analysis of the content the three project reports.

Crowdsourced repositories have become an increasingly important source of information for users and businesses in multiple domains. Everyday examples of tourism crowdsourcing platforms focusing on accommodation, food or travelling in general, influence consumer behaviour in modern societies. These repositories, due to their intrinsic openness, can strongly benefit from independent data quality modelling mechanisms. In this context, building trust & reputation models of contributors and storing crowdsourced data using distributed ledger technology allows not only to ascertain the quality of crowdsourced contributions, but also ensures the integrity of the built models. This paper presents a survey on distributed trust & reputation modelling using blockchain technology and, for the specific case of tourism crowdsourcing platforms, discusses the open research problems and identifies future lines of research.

Alzheimer's disease (AD) is an incurable and highly debilitating condition characterized by the progressive degeneration and/or death of nerve cells, which leads to manifestation of disabilities in cognitive functioning. In recent years, the development of biosensors for determination of AD's main biomarkers has made remarkable progress, particularly based on the tremendous advances in nanoscience and nanotechnology. The unique and outstanding properties of nanomaterials (such as graphene, carbon nanotubes, gold, silver and magnetic nanoparticles, polymers and quantum dots) have been contributing to enhance the electrochemical and optical behavior of transducers while offering a suitable matrix for the immobilization of biological recognition elements. Therefore, optical and electrochemical immuno- and DNA-biosensors with higher sensitivity, selectivity and longer stability have been reported. Nevertheless, strategies based on the detection of multiple analytes still need to be improved, as they will play a crucial role in minimizing misdiagnosis. This review aims to provide insights into the conjugation of nanomaterials with different transducers highlighting their crucial role in the construction of biosensors for detection of AD main biomarkers.

Controlled release of aromatic mixtures to the atmosphere is a requirement for scented systems for indoor applications. The product must smell nice, but also be able to last, slowly releasing the perfume over time. Several adsorption materials have been used, for this purpose. In this study, cork was investigated as a potential perfume adsorbent for application in scented drawer sachets and equivalent products. Cork was selected due to its adsorption properties and because it is a natural, renewable, sustainable material. Granulated cork is a significant by‐product in cork industries and it was chosen for adsorption in this work. Linalool, an enantiomeric monoterpene alcohol and one of the main components of several essential oils, was selected as the model compound for adsorption studies. Activated carbon (AC) was used as the reference material. The sorption of linalool to granulated cork and AC was evaluated by HS‐SPME‐GC‐FID. The linalool isotherm on cork was shown to follow a Brunauer‐Deming‐Deming and Teller, Type IV model. The isotherm data on AC can be adjusted to Langmuir and Freundlich models. A maximum adsorption capacity of 3.9x103μg/g was achieved for AC. Desorption studies were performed. Linalool was still released from granulated cork after three equilibrium stages of desorption, whereas only two desorption values were obtained for AC from the equilibrium with highest linalool concentration. Thus, AC demonstrated good adsorption but not good desorption properties. Sorption and desorption studies of linalool from granulated cork, showed that granulated cork could be an excellent material allowing controlled release of the aroma.

Subcritical water extraction (SWE) has become a popular green extraction technique for the isolation of different classes of compounds from natural matrices. Low price, safety and green character of water, good yields of target compounds and reduced energy consumption, make this technique favorable for potential industrial applications. The purpose of this study was to evaluate antioxidant, antimicrobial and cytotoxic activity of four medicinal plants traditionally used in folk medicine of Serbia. Black mulberry (Morus nigra L.), wall germander (Teucrium chamaedrys L.), wild geranium (Geranium macrorrhizum L.) and comfrey (Symphytum officinale L.) were extracted by subcritical water at different temperatures. Antioxidant activity of the extracts was defined by conventional spectrophotometric methods, such as the total phenolic content (TPC), DPPH-radical scavenging activity (DPPH-RSA), ferric reducing antioxidant power (FRAP) and total antioxidant capacity (TAC) assessed by a DNA-based sensor. Additionally, the main phenolic compounds contributing to the antioxidant activity of the produced extracts were also identified and quantified by high performance liquid chromatography with diode array detection (HPLC-DAD). Antimicrobial properties of extracts were evaluated against eight microbial strains. Furthermore, the cytotoxic activity was observed for two human cancer cell lines and a cell line derived from murine fibroblast.

According to the recent statistics, Salmonella is still an important public health issue in the whole world. Legislated reference methods, based on counting plate methods, are sensitive enough but are inadequate as an effective emergency response tool, and are far from a rapid device, simple to use out of lab. An overview of the commercially available rapid methods for Salmonella detection is provided along with a critical discussion of their limitations, benefits and potential use in a real context. The distinguished potentialities of electrochemical biosensors for the development of rapid devices are highlighted. The state-of-art and the newest technologic approaches in electrochemical biosensors for Salmonella detection are presented and a critical analysis of the literature is made in an attempt to identify the current challenges towards a complete solution for Salmonella detection in microbial food control based on electrochemical biosensors.

The amphibian skin plays an important role protecting the organism from external harmful factors such as microorganisms or UV radiation. Based on biorational strategies, many studies have investigated the cutaneous secretion of anurans as a source of bioactive molecules. By a peptidomic approach, a novel antioxidant peptide (AOP) with in vitro free radical scavenging ability was isolated from Physalaemus nattereri. The AOP, named antioxidin-I, has a molecular weight [M+H]+ = 1543.69Da and a TWYFITPYIPDK primary amino acid sequence. The gene encoding the antioxidin-I precursor was expressed in the skin tissue of three other Tropical frog species: Phyllomedusa tarsius, P. distincta and Pithecopus rohdei. cDNA sequencing revealed highly homologous regions (signal peptide and acidic region). Mature antioxidin-I has a novel primary sequence with low similarity compared with previously described amphibian's AOPs. Antioxidin-I adopts a random structure even at high concentrations of hydrophobic solvent, it has poor antimicrobial activity and poor performance in free radical scavenging assays in vitro, with the exception of the ORAC assay. However, antioxidin-I presented a low cytotoxicity and suppressed menadione-induced redox imbalance when tested with fibroblast in culture. In addition, it had the capacity to substantially attenuate the hypoxia-induced production of reactive oxygen species when tested in hypoxia exposed living microglial cells, suggesting a potential neuroprotective role for this peptide.

Fitness centres (FC) represent a unique indoor microenvironment. Exercising on regular basis provides countless health benefits and improves overall well-being, but if these facilities have poor indoor air quality, the respective exercisers might be subjected to some adverse risks. Considering the limited existent data, this work aimed to evaluate particulate pollution (PM10, PM2.5, and ultrafine particles - UFP) in indoor air of FC and to estimate the respective risks for occupants (both staff and exercising subjects). Sampling was conducted during 40 consecutive days of May-June 2014 in general fitness areas, studios and classrooms (for group activities) of four different fitness centres (FC1-FC4) situated within Oporto metropolitan area, Portugal. The results showed that across the four FC, PM10 ranged between 5 and 1080 μg m-3 with median concentrations (15-43 μg m-3) fulfilling the limit (50 μg m-3) of Portuguese legislation in all FC. PM2.5 (medians 5-37 μg m-3; range 5-777 μg m-3) exceeded thresholds of 25 μg m-3 at some FC, indicating potential risks for the respective occupants; naturally ventilated FC exhibited significantly higher PM ranges (p < 0.05). Similarly, UFPs (range 0.5-88.6 × 103 # cm-3) median concentrations were higher (2-3 times) at FC without controlled ventilation systems. UFP were approximately twice higher (p < 0.05) during the occupied periods (mean of 9.7 × 103vs. 4.8 × 103 # cm-3) with larger temporal variations of UFP levels observed in general fitness areas than in classrooms and studios. Cardio activities (conducted in studios and classrooms) led to approximately twice the UFPs intakes than other types of exercising. These results indicate that even short-term physical activity (or more specifically its intensity) might strongly influence the daily inhalation dose. Finally, women exhibited 1.2 times higher UFPs intake than men thus suggesting the need for future gender-specific studies assessing UFP exposure.

BACKGROUND Sweet cherries (Prunus avium L.) and sour cherries (Prunus cerasus L.) contain substantial amounts of anthocyanins and polyphenolics, and their stems have been used in traditional medicine for centuries. However, comparative data on the composition of sweet and sour cherry stems using the same analytical methodologies are limited. Moreover, there is no data in terms of biological activity of subcritical water extracts of cherry stems. RESULTS AND DISSCUSION Results obtained by using several assays that focused on different mechanisms showed that subcritical water extracts of sour and sweet cherry stems were powerful antiradicals and antioxidants. Anti‐proliferative properties measured by MTT (3‐[4,5‐ dimethylthiazol‐2‐yl]‐2,5 diphenyl tetrazolium bromide) test showed prominent cytotoxicity against different tumor cell lines. Inhibitory concentrations obtained were in the range 8.38–11.40 µg mL‐1. GC–MS (gas chromatography mass spectrometry) analysis showed the presence of alcohols, fatty acids, organic acids and other organic compounds. However, the chemical compositions of the two samples observed were similar, indicating similar chemical composition of sour and sweet cherry stems. CONCLUSION Subcritical water extracts of cherry stem demonstrated excellent biological activity and the potential to be used for pharmaceuticals or supplements due to confirmed high antioxidant, antiradical and antitumor activity.

BACKGROUND Morus nigra (mulberry) fruit has been reported as a source of bioactive compounds, although information about their leaves is very limited. Usually, they are considered wastes and have been traditionally used only for tea preparation. The main objective of this work was to explore the valorization of mulberry leaves by polyphenols microwave‐assisted extraction (MAE) and characterization of their antioxidant activity and phenolic composition. A 23 factorial design combined with response surface methodology were applied to characterize the effect of main microwave parameters on total phenolic content (TPC). RESULTS The optimized MAE conditions were 20 mL of ethanol:water (1:1; v/v), 120 °C, 28 min, 0.414 g and medium stirring speed. Under these conditions, TPC was 19.7 ± 2.0 mg gallic acid equivalents (GAE) g‐1 dry plant (DP), and antioxidant activity was 15.3 ± 1.0 mg ascorbic acid (AA) g‐1 DP (ferric reduction activity power –FRAP– assay), 18.6 ± 1.3 mg Trolox equivalents (TE) g‐1 DP (2,2‐diphenyl‐1‐picrylhydrazyl –DPPH– assay) and 186 ± 15 mg TE g‐1 DP (oxygen radical absorbance capacity –ORAC– assay). When compared with ultrasound extraction and Pharmacopeia reference method, MAE was more efficient, representing a valuable technology. Of the 13 compounds identified by HPLC, the most abundant were rutin, chlorogenic, β‐resorcylic and caffeic acids. CONCLUSION These results indicate that mulberry leaves are of potential interest for agro‐food industries as a new source of natural antioxidants.