13 documents found, page 1 of 2
High lignin content polymer filaments as carbon fibre precursors
Ribeiro, Rui; Guerreiro, Miguel; Reis, Renato; Martins, Joana T.; Vieira, J.M.P.; Silva, Mariana Martins da; Covas, J. A.; Paiva, Maria C.The growing environmental awareness, the search for alternatives to fossil resources, and the goal of achieving a circular economy have all contributed to the increasing valorization of biowaste to produce bio-based polymers and other high-value products. Among the various biowaste materials, lignin has gained significant attention due to its high aromatic carbon content, low cost, and abundance. Lignin is pred...
Ecological modelling of cephalopods under climate change, with a special focus ...
Guerreiro, MiguelCephalopods have been hypothesized as winners of Climate change. This thesis tackles this hypothesis by studying the future trends of decapodiform cephalopod biogeography under climate change, using species distribution models. Specifically, in Chapter 2 we projected the distributions of the most harvested squids into 2100 and 2050, and revealed a trend of decreasing habitat availability, especially in the Sout...
Development of electrically conductive polymer nanocomposites for the automotiv...
Guerreiro, Miguel; Rompante, Joana; Leite, André Costa; Fernandes, Luís Paulo; Santos, Rosa Maria; Paiva, Maria C.; Covas, J. A.Environmental concerns and the urgent need for reduction of fossil fuel consumption motivate materials research towards increased transportation efficiency. This work investigates the possibility of reducing the weight of electrical cables in automotive applications by replacing part of the metallic screen with electrically conductive polymer/carbon nanotube (CNT) nanocomposites. PP and PA12 were tested as poss...
How entrepreneurial orientation and stakeholder engagement shape innovation at ...
Monarca, Adélia; Martins, Carlos; Torres, Isabel; Barradas, Daniel; Guerreiro, Miguel; Rodrigues, PauloPURPOSE OF THE RESEARCH The importance of innovation today is fully recognized by both academic and business communities (Chesbrough, 2006). The sustainability of family-owned enterprises involves linking innovation with the entrepreneurial orientation of their decision makers (Kaufmann and Shams, 2015; Bughin, Chui and Johnson, 2008; Smith and Lohrke, 2008). This paper aims to verify how the entrepreneurial or...
Biology and ecology of the world’s largest invertebrate, the colossal squid (Me...
Rosa, Rui; Lopes, Vanessa; Guerreiro, Miguel; Bolstad, Kathrin; Xavier, José C.The colossal squid Mesonychoteuthis hamiltoni (Robson 1925) is the largest (heaviest) living invertebrate and although it is preyed upon by many top predators, its basic biology and ecology remain one of the ocean’s great mysteries. The present study aims to review the current biological knowledge on this squid. It is considered to be endemic in the Southern Ocean (SO) with a circumpolar distribution spreading ...
Deficit in digestive capabilities of bamboo shark early stages under climate ch...
Rosa, Rui; Pimentel, Marta; Galan, Juan; Baptista, Miguel; Lopes, Vanessa M.; Couto, Ana; Guerreiro, Miguel; Sampaio, Eduardo; Castro, JoanaLittle empirical information is currently available on the potential effects of acidification and/or warming in sharks, but none exist about digestive capabilities under such future conditions. Here, we investigated the impact of both acidification (ΔpH = 0.5) and warming (+4; 30 °C) on the digestive enzyme levels of recently hatched tropical bamboo shark (Chiloscyllium punctatum). Thirty days post-hatching, ju...
Neuro-oxidative damage and aerobic potential loss of sharks under elevated CO2 ...
Rosa, Rui; Paula, José Ricardo; Sampaio, Eduardo; Pimentel, Marta; Lopes, Ana Rita; Baptista, Miguel; Guerreiro, Miguel; Santos, Catarina; Campos, DerekSharks occupy high trophic levels in marine habitats and play a key role in the structure and function of marine communities. Their populations have been declining worldwide by ≥90 %, and their adaptive potential to future ocean conditions is believed to be limiting. Here we experimentally exposed recently hatched bamboo shark (Chiloscyllium punctatum) to the combined effects of tropical ocean warming (+4; 30 °...
Habitat and trophic ecology of Southern Ocean cephalopods from stable isotope a...
Guerreiro, Miguel; Phillips, Richard A.; Cherel, Yves; Ceia, Filipe R.; Alvito, Pedro; Rosa, Rui; Xavier, José C.Although cephalopods play a critical role in marine food webs both as predators and prey, there is a limited knowledge of several basic aspects of their ecology, including their habitat and trophic level, in the Southern Ocean. We examined the ecological role of several Southern Ocean cephalopod species by analyzing δ13C and δ15N values in lower cephalopod beaks obtained from diet samples of wandering albatross...
Cephalopods in the diet of nonbreeding black-browed and grey-headed albatrosses...
Alvito, Pedro M.; Rosa, Rui; Phillips, Richard A.; Cherel, Yves; Ceia, Filipe R.; Guerreiro, Miguel; Seco, José; Baeta, Alexandra; Vieira, Rui P.The food and feeding ecology of albatrosses during the nonbreeding season is still poorly known, particularly with regard to the cephalopod component. This was studied in black-browed Thalassarche melanophris and grey-headed T. chrysostoma albatrosses by analysing boluses collected shortly after adults returned to colonies at Bird Island, South Georgia (54°S, 38°W), in 2009. Based on stable isotopic analyses of...
Polar marine biology science in Portugal and Spain: Recent advances and future ...
Xavier, José C.; Barbosa, Andrés; Agustí, Susana; Alonso-Sáez, Laura; Alvito, Pedro; Ameneiro, Julia; Ávila, Conxita; Baeta, Alexandra; Canário, JoãoPolar marine ecosystems have global ecological and economic importance because of their unique biodiversity and their major role in climate processes and commercial fisheries, among others. Portugal and Spain have been highly active in a wide range of disciplines in marine biology of the Antarctic and the Arctic. The main aim of this paper is to provide a synopsis of some of the results and initiatives undertak...