Browsing by Issue Date, starting with "2019-12"
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- Automatización de textos periodísticos en la televisión brasileña: Estudio de caso del sistema AIDA (Globo-Brasil)Publication . Essenfelder, Renato; Canavilhas, João; Maia, Haline; Pinto, RicardoLos avances tecnológicos han creado un ecosistema mediático en el que el periodismo tradicional ve su existencia fuertemente amenazada por el surgimiento de nuevos actores. Las redes sociales han creado un entorno competitivo que, ya sea por su dispersión o por su capilaridad, relegaron los mainstream media a un rol secundario en el ecosistema mediático. Irónicamente, las tecnologías que amenazan el periodismo tradicional son asimismo aquellas que pueden salvarlo, siempre que se utilicen correctamente. El periodismo, debilitado por los efectos de la crisis económica y con redacciones cada vez más reducidas, tiene en la inteligencia artificial una oportunidad de recuperar cierta centralidad en el ecosistema de los medios. En este trabajo se estudia AIDA, un proyecto de la televisión brasileña Globo. Este proyecto buscó en la automatización una respuesta para evitar errores y ambigüedades en las noticias. El estudio del caso AIDA, complementado con entrevistas, presenta los desafíos para lograr la automatización en la lectura y presentación de datos de sondeos electorales.
- Developments towards the use of drones in the building envelope condition assessmentPublication . Falorca, Jorge; Lanzinha, JoãoThis book presents a study on the effectiveness of using drones in the technical inspection of building envelope, as an excellent alternative to more expensive and heavier conventional means. A comprehensive literature review is firstly focused on the drone technology, analysing afterwards the applications in the Construction Industry (CI), with emphasis in the scope of building envelope inspections. Field tests with drones were also performed and the resulting data was treated in order to obtain a facade pathologies diagnosis with a highest degree of accuracy. It has been checked that the use of drones is effectively a promising alternative methodology to support the technical inspection and diagnosis of building envelope pathologies, particularly when displaying a multirotor configuration, loading high-definition (HD) cameras, for both stills photography and video. This view can offer valuable input to enable a greater awareness of the use of drones, particularly in hard-to-reach locations, to the detriment of conventional means. This methodology can bring great benefits, particularly from an environmental impact point of view, since the resources used are much lower. Furthermore, a very reliable diagnosis can be achievable more quickly, and at a much lower cost.
- Deliberative Framings and the Constitution of “Geringonça”: From Media Frames to Reader’s CommentersPublication . Correia, João Carlos; Morais, RicardoThis article analyses how the formation of the XXIst Portuguese Constitutional Government, supported by the Parliamentarian Left (Socialist Party, Communist Party and the far-left organization Left Block that holds together fringes from ecologists movements, Trotskyists groups, and ex-Maoists organizations) was framed by “Observador”, a right-wing online newspaper, ideologically opposed, from the editorial point of view, to the new Government. Simultaneously, we aim to understand if this framing process was followed by the audience. The comments posted by the newsreaders on the website but also on Facebook were analyzed during the formation of the new political solution. The goal was to determine whether there was a relationship between the frames used by the medium, and the opinion expressed by its readers. The results show a higher presence of the game-strategy frame in the media coverage of XXIst Constitutional Government formation process, but a closer look reveals that the most common employed narrative frames were on political impacts and conflict stories, resulting from an accentuated political turn to the left. Our analysis shows that the “Observador”’s audience triggered different interpretative frameworks always sharing an opposition to the formation of the left Government.
- Production and characterization of electrospun membranes for wound dressing applicationsPublication . Miguel, Sónia Alexandra Pereira; Correia, Ilídio Joaquim SobreiraAccording to the World Health Organization, it is estimated that 180 000 deaths occur, every year, as consequence of burns. In United States, it is expected that chronic wounds (e.g. diabetic and pressure ulcers) affect 6.5 million people. Thus, skin lesions are a public health problem. To minimize the effects of skin injuries, it is crucial to protect the wound site for decreasing the risk of infection, as well as promote/accelerate the wound healing process. In this context, researchers have been developing different types of biomaterials (e.g. hydrocolloids, sponges, hydrogels, membranes) to provide a barrier against microorganisms, avoid the dehydration, and enhance the healing process. Among them, the membranes obtained through the electrospinning technique have been investigated for wound dressing applications. This technique allows the production of fibers networks with diameters between 50-500 nm, that mimic the dimensions of the collagen fibers found in the skin’ extracellular matrix. Furthermore, the membranes’ high porosity and small pore size allow gaseous exchanges and exudates absorption, as well as provide protection at the wound site from microorganisms’ invasion and dehydration. Moreover, the electrospun membranes have been functionalized with antibacterial molecules (e.g. antibiotics, silver nanoparticles, and natural extracts) or molecules with biological activity (growth factors, vitamins, and anti-inflammatory) to improve the skin regeneration process. Among the different types of molecules, the natural extracts, like Aloe Vera (AV) and essential oils, have triggered the attention of the researchers to produce wound dressings, due to their excellent biological properties and beneficial effects for the healing process. More recently, researchers started to explore the production of the membranes with asymmetric structure to be applied as wound dressings. These membranes are composed of two layers, that mimic the morphology of native skin, thereby reproducing the properties of the epidermis and dermis. Heretofore, the asymmetric membranes were mainly produced by using dry/wet phase and supercritical carbon dioxide (scCO2)- assisted phase inversion techniques. Taking this into consideration, the work plan developed during my PhD had as main goal to explore the electrospinning technique to produce asymmetric membranes, aimed to improve healing process. To accomplish that, different strategies were explored: i) production of asymmetric electrospun membranes by combining different types of polymers (naturals (silk fibroin (SF), hyaluronic acid (HA), silk sericin (SS) and/or synthetic); ii) incorporation of biomolecules within nanofibers to improve the biological properties of membranes (AV and thymol (THY)); iii) combination of the electrospun nanofibrous membranes with three-dimensional (3D) printed hydrogels, to obtain an asymmetric skin substitute. In the first study presented in thesis, an asymmetric electrospun membrane with a top layer composed of Polycaprolactone (PCL) and a bottom layer of CS/AV was produced and characterized. The results obtained in this study demonstrated that the low porosity and hydrophobic character exhibited by top layer was crucial to avoid the microorganism infiltration (S. aureus) and Escherichia coli (E. coli)). On the other side, the AV incorporation into CS nanofibers allowed the production of a bottom layer that was able to provide a moist environment at the wound site, as well as promote an improved fibroblasts’ adhesion and proliferation. Further, the microorganism growth at bottom layer’ surface was inhibited due to the antimicrobial properties of CS and AV. In the second study presented herein, SF was used to produce an asymmetric electrospun nanofibrous membranes, in which a bioactive compound (THY) was incorporated to improve the wound healing process. SF is a fibrous protein, that presents excellent biocompatibility, good water vapor permeability, biodegradability, mechanical strength, and minimal inflammatory reaction. In this way, the SF was combined with PCL to produce the top layer, that mimic the epidermis layer. On the other hand, SF was also mixed with HA to produce a bottom layer that mimic the dermis layer. This polymeric combination allowed the production of a structure able to absorb the wound exudates and promote the cell’s adhesion and proliferation. In addition, THY was incorporated into the bottom nanofibrous membrane to provide antibacterial and antioxidant properties. The results obtained showed that the top layer of the asymmetric membrane displays a low porosity was able to avoid microorganisms’ infiltration, whereas the high porosity of the bottom layer is crucial to assure a moist environment at the wound site as well as promote the cellular migration/infiltration. Further, the mechanical assays demonstrated that the asymmetric membranes displayed mechanical parameters that are similar to those exhibited by native skin. On the other side, the in vitro assays demonstrated that the human fibroblasts adhered and proliferated at the membranes’ surface, and the THY incorporation into bottom layer conferred antioxidant and antibacterial properties to the membrane. In the third study presented in this thesis, a 3D skin asymmetric construct (SAC) was produced, by combining the electrospinning and the 3D printing techniques. In this work, the asymmetric skin construct was obtained through the combination of materials (that was performed for the first time) and by using different production techniques to reproduce the properties/structure of epidermis and dermis. In this way, the electrospinning technique was used to obtain a top layer composed of a nanofibrous mesh presenting excellent mechanical properties and gaseous exchange capacity. On the other side, the dermis-like layer was produced by using the 3D printing of hydrogel, allowing to achieve a 3D structure able to absorb high amounts of exudate, as well as to promote the cell migration. The obtained results demonstrate that the epidermis-like top layer composed of PCL and SS electrospun nanofibers avoided the microorganisms’ infiltration (S. aureus and Pseudomonas aeruginosa (P. aeruginosa)) and displayed excellent mechanical properties quite similar to those of the native skin. In contrast, the bottom layer produced, by performing the 3D printing of CS and sodium alginate (SA) hydrogel, presented suitable porosity, wettability, and biological properties that supported fibroblasts’ adhesion, migration and proliferation. Further, the antimicrobial properties of CS enabled the inhibition of the S. aureus and P. aeruginosa growth at the bottom layer’s surface. Overall, the results obtained in these experimental works demonstrate the versality of the electrospinning technique, which allows to combine different natural/synthetic polymers, incorporate biomolecules within nanofibers, and produce two distinct layers that mimic the epidermis and dermis features. On the other side, membranes’ performance on the treatment of skin injuries can be improved by the incorporation of biomolecules or cells. The use of the other techniques can also be hypothesized to produce structures with a personalized shape/size that fulfil the patient needs. Further, the realization of in vivo assays may reveal promising results that will speed up the evaluation of these skin substitutes in clinical assays.
- Telemonitoring Devices and Systems: Current Status and Future TrendsPublication . Machadeiro, Liliana Tavares; Gaspar, Pedro Dinis; Castelo-Branco, MiguelIn the future, the number of elderly and chronically ill will be quite large. Additionally, pathologies will in many cases be in comorbidity. Along with this reality, the health care resources will be insufficient for the population, thus the current research for technological solutions needs to be implemented in the future. There are available several telemonitoring devices and systems for chronic diseases. Massive use of these devices will be essential to address the current and future lack of health system resources. Research on telemonitoring devices and systems for chronic diseases was conducted in academic and scientific databases. The technical specifications were collected from the manufacturers’ web page. The collected data was analysed and compared in order to propose scenarios for the future trend of technical specifications required in telemonitoring devices/system. Telemonitoring for chronic diseases can bring great benefits to patient and health systems. Widening this practice will be a reality in the near future. This procedure will be fostered by the promotion and regulation of interoperability between devices/systems, as well as of front-end programs providing the link between health support systems. Interoperability issues are the main flaws of telemonitoring devices/systems on the market today.
- Modelos de negócios para o jornalismo regional: o caso Setúbal na RedePublication . Ramos, Giovanni; Correia, João CarlosEsta investigação foi desenvolvida como base da nossa tese doutoral1, que elegeu como objeto de estudo a análise da produção discursiva dos meios de comunicação sobre a universidade pública brasileira durante a greve de professores e funcionários, em 2015. O objetivo central foi o de analisar os discursos subjacentes aos textos publicados pela grande mídia sobre a universidade pública brasileira, a partir das notícias veiculadas durante os cinco meses da greve, com a finalidade de desvelar as estratégias de veiculação de pontos de vista sobre a universidade e o movimento paredista. Tais posições são representativas dos interesses de diferentes grupos sociais que constroem uma hegemonia discursiva no âmbito das disputas de sentidos produzidas no período estudado. Utilizamos alguns conceitos propostos por Pierre Bourdieu e recorremos também a produções do autor que discutem o jornalismo por produzir mecanismos de construção seletiva de opiniões e representações sobre a realidade social. Integraram a análise e interpretação dos dados alguns tópicos chaves das teorias da comunicação. Palavras-chave: Campo jornalístico, poder simbólico, grande mídia, análise crítica do discurso, universidade
- The relevance of public speech in the presidency of Donald Trump – the US elections in analysisPublication . Costa, Bruno; Khudoliy, AnatoliyThe importance of the US presidential elections results from the analysis of several factors, both at the systemic level and their impact on the international political order. In the middle term of the Donald Trump’s presidency, it is important to analyze the discourse model used and its impact on election results. In fact, many studies have focused on the characteristics of the voters that led to Trump’s victory, leading a short discussion about the importance and the role of public speech in the electoral battle of 2016. The campaign discourse and the way Donald Trump keep the communication strategy during the mandate is a key element to understand the US political system and could represent a new model to analyze the different concepts of leadership at a global level. A close insight into it can illustrate many facets and facts about discourse as an instrument in electoral campaign and how it is perceived by voters. The study investigates D. Trump’s speeches during the 2016 presidential elections in order to identify his sentiments, discourse themes and strategies. We used the technique of content analysis and eventanalysis, along with the descriptive approach, with the aim of outlining the impact of Donald Trump’s public speeches during this period. The study revealed that Trump’s speeches were topic oriented. The study allowed us to deepen the knowledge about the role of political public speeches and the new strategy adopted by Donald Trump to keep a significant average of supporters.
- The effects of warming up strategies for sprint performance: Emerging approachesPublication . Gil, Maria Helena Gonçalves; Marinho, Daniel Almeida; Neiva, Henrique PereiraIn recent years, the benefits of warm-up in sports performance have received a special interest. New methods have been included in warm-up procedure, but few are known about the effects on running performance and biomechanical responses. Thus, the purpose of the current thesis was to analyze the effect of recent trends of warm-up tasks on sprint performance. Specifically, to verify the effects of including ballistic exercises in warm-up procedures and to analyze the impact of changing biomechanical running patterns during warm-up, conducting a performance, biomechanical, physiological and psychophysiological evaluation of sprints. For this, the following steps were performed: (i) qualitative review on warm-up and performance, focusing on the emerging methods; (ii) to verify the acute effects of a warm-up including ballistic exercises inducing a post-activation potentiation, easy to apply on a real competition context, in repeated 100m running performance; (iii) to understand the acute physiological, psychophysiological and biomechanical responses of including ballistic exercises in repeated 30m running performance; (iv) to analyze the effect of manipulating running kinematics (stride length (SL) and stride frequency (SF)) during warm-up in repeated 30m running performance. The main conclusions of the study were: (i) considering the new trends that have emerged, it can be suggested positive effects on performance after short duration stretches followed by specific muscle activation exercises, and after dynamic stretching, both depending on the duration and intensity; short-duration maximal efforts and specific to the following activity, followed by few minutes of recovery, provide beneficial neuromuscular responses and improved performance in high-intensity and short-term efforts; passive heating during the transition phase between warm-up and main exercise lead to optimization of subsequent performance; (ii) there were benefitial effects of warm-up in 30m and 100m sprinting; (iii) the 100m race is equally optimized after warm-up with or without post-activation potentiation, but with different running kinematics (iv) the positive effects of warm-up on 30m running was caused by faster initial 15m and increased SL in the last 15m of the trial; v) no additional effects on 30m were found after including ballistic exercises during warm-up; (vi) a warm-up focusing in higher SL or higher SF did not result in different 30m sprint performances and running kinematics, despite different running strategies occurred (faster initial meters after warm-ups stimulating SF and faster final meters after warm-up stimulating SL); (vii) the results highlighted the individual response to each warm-up procedure. The main findings of this work emphasize the importance of the warm-up design for short running distances and the need of individualization for optimized performances. Further studies are needed to deeply understand their effects on performance.
- A participatory ergonomics approach to prevention of musculoskeletal disorders in Portuguese small and medium enterprises: Ergo@OfficePublication . Lima, Tânia M.; Coelho, DenisA participatory ergonomics program enables a company to engage employees in its preventive strategy. This paper presents Ergo@Office, an integrated methodology devised for promoting continuous implementation of preventive measures while monitoring their effectiveness over time in a participatory manner. It consists of a straightforward and cost-effective resource which is primarily aimed at supporting the identification of the need for implementation of interventions for strategic prevention of musculoskeletal disorders. As a practitioner tool, Ergo@Office guides the deployment of a participatory approach to ergonomics in both the analysis as well as in the intervention phase. The implementation of the measures envisaged in this planning support framework result from teamwork between the OSHS (Occupational Health and Safety Services) and the employee whose work is under focus. The implemented measures should then be monitored, which will enable assessing their effectiveness and their adjustment to the labour setting in an up-to-date manner.
- Development of layer-by-layer polymeric microneedles for cancer local delivery of therapeuticsPublication . Moreira, André Ferreira; Correia, Ilídio Joaquim SobreiraCancer is one of the leading causes of morbidity and mortality of the worldwide population. The treatments currently applied in the clinic, such as surgery, chemotherapy, and radiotherapy, present low therapeutic efficacies and induce systemic toxicity. This reality highlights the need to develop new anticancer approaches that can improve not only the therapeutic efficacy but also reduce/avoid the interactions with healthy tissues and consequently the side effects. Furthermore, the researchers have also been exploring the combinatorial therapeutic approaches to overcome the cancer cells resistance mechanisms and maximize the antitumoral effect. Among the various combinatorial therapies, the simultaneous administration of photothermal (PTT) and chemotherapy regimens has shown promising results in preclinical trials. Particularly, researchers have been focused on the utilization of nanomaterials that can mediate a PTT effect in response to near-infrared light (NIR; 700-1100 nm) and that promote a tumor-specific delivery of chemotherapeutic agents. The use of NIR light to mediate the PTT effect is fundamental since the major biological components have minimal absorption in this region of the spectrum. Among the various NIR-responsive nanomaterials, gold-core mesoporous silica shell (AuMSS) nanoparticles are promising candidates for medical applications. These materials can combine on a single platform the properties of a PTT, drug carrier, and bioimaging agent. The gold nucleus, mainly the anisotropic morphologies, due to the surface plasmon resonance phenomenon can be optimized to present a high absorption in the NIR region, which allows the production of a localized PTT effect capable of inducing cancer cell death. On the other side, the mesoporous silica coating provides a large surface area and pore volume that allows the encapsulation of different chemotherapeutic agents. Additionally, the mesoporous silica layer stabilizes and protects the gold core from degradation upon irradiation with energetic radiations (i.e. photodegradation) such as the NIR light. However, despite the promising results presented by these nanomedicines, their translation into the clinic has been quite limited. Such has been attributed to the nanostructures’ reduced accumulation in human tumors (i.e. latest data indicates that less than 0.7% of the administered nanoparticle dose can successfully reach the tumor site), high complexity, and difficulty to synthesize large batches. Thus, in the last years has been observed a paradigm shift and researchers started to re-explore the use of macroscale delivery systems (e.g. microneedles and hydrogels) to promote a controlled and localized delivery of therapeutics to tumor tissue. Particularly, the use of microneedle systems has shown promising results that support their application in anti-tumor therapy. Microneedles-based devices can be manufactured using a variety of materials (metals, polymers, and ceramics) as well as with different morphologies and organizations. These systems can be used to increase the permeation of therapeutic agents in the target tissue or to promote the delivery of such agents when encapsulated in their structure to deeper regions of the tumor tissue in a controlled manner. In general, in cancer therapy applications, the microneedles have been explored to activate anticancer immune responses from the host (antigens, genetic material, and immune adjuvants) or to deliver agents with anticancer activity (drugs and nanoparticles). Thus, the local application of microneedle systems has the potential to increase the distribution and quantity of therapeutic agents that accumulate in the deepest regions of the tumor region while simultaneously reducing their interaction with adjacent healthy tissues. Considering the advantages of the localized delivery of anticancer therapies, the main objective of this thesis’ work plan was the development of a layer-by-layer (LbL) microneedle system to mediate the simultaneous delivery of AuMSS nanorods and chemotherapeutic agents. Such was pursued by (i) exploring a production method of AuMSS nanorods with imaging and therapy properties; ii) optimizing a nano-in-micro system that can incorporate these nanoplatforms and allow to control the release rate in response to variations in pH and temperature; and iii) developing a microneedle system that can improve the therapeutics penetration in the tumor and promote the local and combined administration of AuMSS nanorods PTT agents and chemotherapeutic drugs. In the first study presented in this thesis, the therapeutic capacity of poly-2-ethyl-2-oxazolines (PEOZ) functionalized AuMSS nanorods loaded with doxorubicin (Dox) was evaluated. Gold nanorods were produced using a method called “seed-mediated growth” and then were coated with a mesoporous silica layer using the Stöber's modified method. Thereafter, a PEOZ polymer previously modified with a silane was used to functionalize the AuMSS nanorods’ surface via a condensation process. The PEOZ grafting on the AuMSS nanorods induced the neutralization of nanodevices’ surface charge, from -30 mV to -15 mV. Further, there was also an improvement in the AuMSS nanorods’ biocompatibility, particularly reducing the blood hemolysis to negligible values at a nanoparticle concentration of 200 μg.mL-1. Additionally, the nanorods’ functionalization did not impact their PTT capacity mediating a temperature increase of about 40ºC when irradiated with NIR light for 5 min. On the other side, the in vitro assays performed with cervical cancer cell lines revealed that the combined treatment mediated by the PEOZ coated AuMSS nanorods result in a synergistic effect, allowing the complete eradication of cervical cancer cells. In the second study, a nano-in-micro approach was explored for allowing the intra-tumoral administration of salicylic acid (SA) and Dox-loaded AuMSS nanorods. For this purpose, poly(lactic-co-glycolic acid) (PLGA) microparticles containing the nanorods and Dox were produced using a water-in-oil-in-water method. The obtained results showed that the microparticles could act as a drug and nanoparticle delivery agent. Moreover, the PLGA microparticles presented a pH (activated by acidic pH) and NIR light irradiation (heat production) dependent drug release profile. Further, in in vitro studies, the microparticles shown to be biocompatible and internalized by cervical cancer cells. Additionally, assays performed on 3D cell culture models (tumor spheroids) demonstrated that the microparticle-mediated combinatorial therapy caused a reduction of 50% in the spheroids’ size as well as induced the death of more than 60% of the cancer cells present in the spheroids within 48 h of incubation. In the third study presented in this thesis, the therapeutic potential of the combinatory therapy mediated by microneedle device with a layer by layer organization was evaluated. Initially, a polyvinylpyrrolidone (PVP) microneedle (4x4 tips) system was produced using the micromoulding technique. Subsequently, this base layer of the microneedle system was coated using the electrospraying technique, thereby introducing a Dox-containing chitosan (Ch) layer and an AuMSS nanorods-enriched polyvinyl alcohol (PVA) layer. The results showed that the produced microneedles had a bevel-like tip with a width of 425 μm, a height of 1420 μm and a distance between tips of 1740 μm. Additionally, the microneedles were mechanically resistant to withstand the application on the tumor tissue (agarose tumor-mimicking gels) and release their charge sequentially and in response to acidic pH and NIR light irradiation. In in vitro studies, the microneedles-mediated combinatorial therapy was more effective against cervical cancer cells than the individual therapies. In fact, when only the chemotherapy or PTT were administered, a reduction in the cancer cells viability to ≈55 and ≈80%, respectively, was observed, whereas the microneedles combinatorial therapy led to the eradication of the cancer cells (less than 5% of viable cells). In summary, the data obtained from these studies demonstrate the applicability of localized delivery systems in cancer therapy. Apart from the microneedles’ advantages, the therapeutic potential of the AuMSS nanorods (PTT) can be enhanced through the combinatory therapies, including chemotherapy through the co-encapsulation of drugs. Additionally, the LbL organization of the microneedle systems represents a simple approach to the development complex and hierarchically organized structures that can encapsulate various therapeutic agents as well as release them in a controlled and orderly manner to maximize the anticancer effect. In the future, preclinical studies in animal models must be performed to determine the potential of these delivery systems for being applied in cancer therapy.