Browsing by Issue Date, starting with "2021-03"
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- Digital platform-based ecosystems: the evolution of collaboration and competition between incumbent producers and entrant platformsPublication . Cozzolino, Alessio; Corbo, Leonardo; Aversa, PaoloThe rise of the Internet has seen traditional incumbent producers challenged by competition from digital entrant platforms. It is unclear, however, how those two types of actors—which are in competition but also mutually dependent—can co-exist in the new platform-based ecosystem. This paper sheds light on that pivotal phenomenon by connecting the traditional literature on incumbent adaptation with the growing conversation on digital platform-based ecosystems. Through a qualitative longitudinal (2005–2019) study of the global digital advertising ecosystem, we examine how incumbent producers pivot between competitive and cooperative strategies in response to digital entrant platforms. Our analysis reveals a process characterized by three sequential phases: (1) selective cooperation, (2) allied competition, and (3) selective coopetition. Those phases show how switching between different multi-level strategies spanning market segments, products, and technological components represents a viable solution for incumbent producers adapting in the face of entrant platforms.
- OpeningPublication . Crespo, Nuno
- Imprinting of founders' entrepreneurial motivations on enterprises' practices and processes: the context of creative industriesPublication . Abecassis-Moedas, Céline; Manceau, Delphine; BenMahmoud-Jouini, Sihem; Pereira, JoanaThis paper explores the imprinting of entrepreneurs' motivations on the practices and processes of enterprises. We investigate the question in the context of creative industries (CIs) as an extreme case of entrepreneurial motivations (EMs) prevalence. We analyse the EM of 14 founders of design consultancies. Three EMs emerge: self-fulfilment, freedom and financial motivation. The qualitative analysis reveals that the founders' EMs at the time of a venture's founding has a lasting impact on the characteristics of the venture (name, processes formalization, decision-making processes, performance measures and growth strategies). Specifically, founders driven by self-fulfilment tend to build ventures named after them. In these ventures, processes are informal, decision-making is centralized, performance measures are based on personal satisfaction and recognition and enterprise growth is restrained. Founders who seek freedom tend to run enterprises with semiformal processes, semicentralized decision-making, a client satisfaction focus, and slow growth strategies. In contrast, founders with financial motivations tend to create enterprises with formal processes, decentralized decision-making, financial performance metrics and growth ambitions. By focusing on EM and adopting a holistic approach beyond some characteristics of the venture, we complement the imprinting literature.
- Emergent technologies for the extraction of antioxidants from prickly pear peel and their antimicrobial activityPublication . Alexandre, Elisabete M. C.; Coelho, Marta C.; Ozcan, Kardelen; Pinto, Carlos A.; Teixeira, José A.; Saraiva, Jorge A.; Pintado, ManuelaPhenolic compounds are important bioactive compounds identified in prickly pear peel that have important antioxidant and antimicrobial properties. However, conventional thermal extraction methods may reduce their bioactivity, and technologies such as high pressure (HP) and ohmic heating (OH) may help preserve them. In this study, both technologies were analyzed, individually and combined (250/500 MPa; 40/70◦C; ethanol concentration 30/70%), and compared with Soxhlet with regard to total phenolics, flavonoids, and carotenoids as well as antioxidant (ABTS, DPPH, ORAC), DNA pro-oxidant, and antimicrobial (inhibition halos, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), growth curves, and viable cells) activities of prickly pear peel extracts. Total phenolics extracted by each technology increased 103% (OH) and 98% (HP) with regard to Soxhlet, but the contents of total flavonoids and carotenoids were similar. Antioxidant activity increased with HP and OH (between 35% and 63%), and OH (70◦C) did not induce DNA degradation. The phenolic compound present in higher amounts was piscidic acid, followed by eucomic acid and citrate. In general, their extraction was significantly favored by HP and OH. Antimicrobial activity against 7 types of bacteria showed effective results only against S. aureus, S. enteritidis, and B. cereus. No synergetic or additive effect was observed for HP/OH.
- ResiliScence 4 COVID-19: social sensing & intelligence for forecasting human response in future COVID-19 scenarios, towards social systems resiliencePublication . Gaspar, Rui; Rodrigues, Ana Paula; Raposo, Beatriz; Godinho, Cristina; Boavida, Fernando; Leiras, Gisela; Toscano, Hugo; Filipe, Jessica; Silva, Jorge Sá; Fernandes, Marcelo; Arriaga, Miguel; Francisco, Rita; Domingos, Samuel; Silva, Susana; Espassandim, TeresaUm cenário amplamente discutido face à atual pandemia, prevê a criação de vacinas para a COVID-19. Mas como responderão os cidadãos noutros cenários, e.g. se não existir vacina? Ou se não existir terapêutica adequada ou imunidade de grupo? Sendo o comportamento humano o mais eficaz mecanismo de controlo social da pandemia na ausência de vacina ou outras medidas de controlo, conseguir prevê-lo permitirá intervir proactivamente, reduzindo a sobrecarga e aumentando a resiliência do Sistema Nacional de Saúde. Com esse fim, foram criados modelos teóricos de gestão e comunicação de crise e modelos preditivos de comportamentos de prevenção do risco por contágio de SARS-CoV-2. Estes foram sustentados em dados de sensores humanos, tendo por base a análise de dados extraídos de redes sociais, inquéritos longitudinais e dados "inteligentes" (recolhidos por smartphone). A partir dos resultados, foram elaboradas recomendações emitidas para a Direção-Geral da Saúde, com vista ao desenvolvimento de estratégias e recursos promotores de mobilização e resiliência social, customizadas às diferentes fases de crise e futuros cenários de pandemia.
- Advances in extraction methods to recover added-value compounds from seaweeds: sustainability and functionalityPublication . Matos, Gabriela S.; Pereira, Sara G.; Genisheva, Zlatina A.; Gomes, Ana Maria; Teixeira, José A.; Rocha, Cristina M. R.Seaweeds are a renewable natural source of valuable macro and micronutrients that have attracted the attention of the scientists in the last years. Their medicinal properties were already recognized in the ancient traditional Chinese medicine, but only recently there has been a considerable increase in the study of these organisms in attempts to demonstrate their health benefits. The extraction process and conditions to be used for the obtention of value-added compounds from seaweeds depends mainly on the desired final product. Thermochemical conversion of seaweeds, using high temperatures and solvents (including water), to obtain high-value products with more potential applications continues to be an industrial practice, frequently with adverse impact on the environment and products’ functionality. However more recently, alternative methods and approaches have been suggested, searching not only to improve the process performance, but also to be less harmful for the environment. A biorefinery approach display a valuable idea of solving economic and environmental drawbacks, enabling less residues production close to the much recommended zero waste system. The aim of this work is to report about the new developed methods of seaweeds extractions and the potential application of the components extracted.
- A utilização de tecnologias touchscreen por crianças até aos 6 anos: breve olhar da psicologia do desenvolvimentoPublication . Costa-Ramalho, SusanaVivemos tempos globalmente dominados por moderna tecnologia, com profundo impacto na vida de cada um. O debate relativo ao seu impacto sobre o desenvolvimento infantil tem sido amplificado, particularmente por pais e educadores que receiam as ameaças que possam trazer à sua segurança e ao bem-estar físico e psicológico, assim como os prejuízos na dimensão relacional. Muito embora se observem mundialmente clivagens digitais, as tecnologias touchscreen misturam-se no nosso quotidiano de modo muito discreto e a grande maioria das crianças usa-as diariamente. Sob o pano de fundo da teoria ecológica de Bronfenbreener, procuramos olhar os resultados de estudos científicos nesta área, entendendo o desenvolvimento humano na interação da Pessoa com os seus contextos, dos quais fazem hoje parte – de modo inalienável – as tecnologias digitais. Ao invés duma perspetiva que entendemos como mais “cinzenta” – afirmando as nossas vidas como sendo globalmente controladas pelas tecnologias - situamos a escrita deste capítulo numa visão da criança como um sujeito em constante desenvolvimento, que se reestrutura e também recria o meio em que se encontra, caracterizando-se a interação entre o sujeito e o mundo pela reciprocidade e mútua interação. Pesando custos e benefícios, os investigadores da área, partilham – de modo geral – uma perspetiva: se formos capazes de proteger as crianças do pior que as tecnologias digitais podem fazer acontecer, ampliamos o seu acesso ao melhor e às vastas possibilidades que elas têm para oferecer. Sugere-se a adoção de uma visão menos tecnocêntrica em que, ao invés de considerar a tecnologia como uma característica definidora da vida das crianças do nosso tempo, pensemos sobre ela como uma das várias atividades em que as crianças se envolvem e que, tal como de todas as outras “partes” que preenchem o quotidiano e constroem o seu desenvolvimento, cabe aos pais/educadores escolher olhares e gestos atentos, responsáveis e sempre promotores de bem-estar.
- Rethinking History through Communication. The "public sphere" as a civic "imagined community" in late 19th century PortugalPublication . Sardica, José Miguel Pereira Alcobio Palma
- Welfare properties of profit maximizing recommender systems: theory and results from a randomized experimentPublication . Zhang, Xiaochen; Ferreira, Pedro Assis; Matos, Miguel Godinho de; Belo, RodrigoRecommender systems have been introduced to help consumers navigate large sets of alternatives. They usually lead to more sales, which may increase consumer surplus and firm profit. In this paper, we ask whether the firms’ choice of recommender system might hurt consumers. We use data from a large-scale field experiment in video-on-demand to measure the price elasticity of demand for movies placed in salient and non-salient slots on the TV screen. During this experiment, the firm randomized the prices and slots in which movies were recommended to consumers. This setting readily allows for identifying the effects of price and slot on demand, and thus computes consumer surplus. We find that consumers are less price-elastic toward movies placed in salient slots. Using the outcomes of this experiment, we simulate how consumer surplus and welfare change when the firm implements several types of recommender systems, namely one that maximizes profit. We show that this system hurts consumer surplus and welfare relative to a system that maximizes welfare. We also show that, in our setting, the system that maximizes profit does not generate less consumer surplus than several recommender systems frequently used in practice. Yet, the amount of extra rent the firm can extract from strategically placing movies in salient slots is still a function of the popularity and quality of movies used to do so. Ultimately, our results question whether recommender systems embed mechanisms that extract excessive surplus from consumers, which may call for better scrutiny.