Browsing by Issue Date, starting with "2020-08"
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- Assessing microplastic uptake and impact on omnivorous juvenile white seabream Diplodus sargus (Linnaeus, 1758) under laboratory conditionsPublication . Müller, Carolin; Erzini, Karim; Teodosio, Maria; Pousão-Ferreira, Pedro; Baptista, Vânia; Ekau, WernerPrevious laboratory feeding experiments, representing the state-of-the-art methodology to investigate micro-plastic (MP) ingestion and its impact for fish, tend to disregard both the significance of applying realistic MP densities and the potential relevance of biofilm-coating for ingestion probability. This experiment assessed the uptake of either pristine or biofilm-coated MP particles and the physiological impacts for juvenile white seab-ream for MP concentrations consistent with those found in the field along with natural prey over a course of 3.5 weeks. Results indicate the ability of juvenile D. sargus to discriminate between edible and non-edible prey. A distinct preference for biofilm-coated over pristine particles could not be verified. No significant impact on growth and condition was found except for high levels of MP ingestion. The outcomes highlight the importance of performing MP feeding experiments mimicking natural conditions to reliably assess the impact of MP on early life stages of fish.
- A new species of Corcyrogobius (Teleostei: Gobiidae) from Ile de Ngor, SenegalPublication . Kovacic, Marcelo; Wirtz, Peter; Schliewen, Ulrich K.Corcyrogobius pulcher sp. nov. is described from off Ile de Ngor. Dakar, Senegal. Corcyrogobius pulcher is distinguished from its two congeners by having the rear edge of the jaws ending posteriorly below mideye, second dorsal fin 1/9, pectoral fin rays 17, pelvic fins oval or truncated posteriorly, scales in lateral series 26-27, anterior oculoscapular head canal with pore beta, suborbital row b of sensory papillae anteriorly beginning below vertical of posterior edge of eye, dark vertical caudal bar, branchiostegal membrane without intense dark spot, cheek with two oblique whitish stripes, the first going from the eye downwards and forward to the posterior jaws, the second on the preopercular, alternating with brown oblique stripe going from behind the eye downwards and forward across the cheek. Furthermore, mitochondrial COI-barcoding data unambiguously support the species-level distinctiveness of the three Corcyrogobius species. A key to the species of Corcyrogobius is provided.
- Addressing Unequal Area Facility Layout Problems with the Coral Reef Optimization algorithm with Substrate LayersPublication . Garcia-Hernandez, L.; Garcia-Hernandez, J. A.; Salas-Morera, L.; Carmona-Munoz, C.; Alghamdi, N. S.; Valente de Oliveira, José; Salcedo-Sanz, S.The Unequal Area Facility Layout Problem (UA-FLP) is a relevant task in industrial manufacturing, in which the disposition of a number of facilities (or departments) in a manufacturing system must be obtained, under several optimization criteria and different constraints. The UA-FLP is a hard optimization problem, in which traditional optimization techniques do not obtain good results. Thus, it has been successfully tackled with different heuristics and meta-heuristics in the last years. In this work we address the UA-FLP with a multi-method ensemble approach, the Coral Reefs Optimization algorithm with Substrate Layers (CRO-SL). It is a novel multi-method evolutionary algorithm that encourages the evolution of several searching procedures at the same time over a single population. The CRO-SL has been previously applied to very difficult optimization problems, obtaining excellent performance. In this case, we adapt the CRO-SL to the UA-FLP, by means of increasing the diversity generation within the algorithm, which is helpful to improve the exploration of the searching space, avoiding to fall into local minima. Specifically, we propose to include several reproduction mechanisms (adapted to the UA-FLP) within each substrate of the algorithm, which will highly increase the diversity generation in the CRO-SL. An exhaustive experimental study of the CRO-SL performance in a large number of UA-FLP instances is carried out, including a comparison with the state-of-the-art algorithms for this problem. We will show the ability of the CRO-SL to reach or surpass the best-known solutions in most of the tested UA-FLP cases.
- Shifts in sexual dimorphism across a mass extinction in ostracods: implications for sexual selection as a factor in extinction riskPublication . Martins, Maria Joao Fernandes; Hunt, Gene; Thompson, Carmi Milagros; Lockwood, Rowan; Swaddle, John P.; Puckett, T. MarkhamSexual selection often favours investment in expensive sexual traits that help individuals compete for mates. In a rapidly changing environment, however, allocation of resources to traits related to reproduction at the expense of those related to survival may elevate extinction risk. Empirical testing of this hypothesis in the fossil record, where extinction can be directly documented, is largely lacking. The rich fossil record of cytheroid ostracods offers a unique study system in this context: the male shell is systematically more elongate than that of females, and thus the sexes can be distinguished, even in fossils. Using mixture models to identify sex clusters from size and shape variables derived from the digitized valve outlines of adult ostracods, we estimated sexual dimorphism in ostracod species before and after the Cretaceous/Palaeogene mass extinction in the United States Coastal Plain. Across this boundary, we document a substantial shift in sexual dimorphism, driven largely by a pronounced decline in the taxa with dimorphism indicating both very high and very low male investment. The shift away from high male investment, which arises largely from evolutionary changes within genera that persist through the extinction, parallels extinction selectivity previously documented during the Late Cretaceous under a background extinction regime. Our results suggest that sexual selection and the allocation of resources towards survival versus reproduction may be an important factor for species extinction during both background and mass extinctions.
- Effectiveness of plant growth-promoting rhizobacterium Pantoea sp. BRM17 in enhancing canola growth on phosphogypsum-amended soilPublication . Trifi, Houda; Ben Salem, Issam; Kolsi Benzina, Naima; Fourati, Amine; Costa, Maria Clara; Achouak, Wafa; Sghaier, Haitham; Saidi, Mouldi
- Fibrilhação auricular - uma abordagem pré-hospitalar “descomplicada”Publication . da Mota, Teresa Faria; Candeias, Rui; Mimoso, Jorge; de Jesus, IlidioA Fibrilhação Auricular (FA) é a arritmia crónica mais comum a nível mundial, com uma prevalência que poderá duplicar nas próximas décadas. O seu diagnóstico baseia-se na análise do ECG de 12 derivações e caracteriza-se habitualmente pela ausência de ondas p e pela irregularidade dos intervalos R-R, embora possam existir exceções. Uma das principais e mais nefastas complicações da FA são os eventos tromboembólicos cerebrais ou periféricos, o que sustenta a pertinência de estabelecer o risco trombótico individual de cada doente e iniciar anticoagulação de acordo com o mesmo.
- Cultural heritage visits supported on visitors' preferences and mobile devicesPublication . Cardoso, Pedro; Rodrigues, Joao; Pereira, Joao; Nogin, Sergey; Lessa, Joana; Ramos, Celia; Bajireanu, Roman; Gomes, Miguel; Bica, PauloMonuments, museums and cities are great places to feel and experience neat and interesting things. But cultural heritage is experienced differently by different visitors. The more erudite may know beforehand what they intend to explore, while the least literate usually know and are capable of expressing some of their preferences but do not exactly realize what to see and explore. This paper proposes the use of a mobile application to set an itinerary where you can move at your own pace and, at the same time, have all the complementary information you need about each of the points of interest. The application is designed in face of an adaptive user interface where the routing and augmented reality are connected to acknowledge the needs of different user categories, such as elders, kids, experts or general users
- Oil palm survival under climate change in Kalimantan and alternative SE Asian palm oil countries with future basal stem rot assessmentsPublication . Paterson, R R MOil palm (OP) is affected by climate change and the cultivation of the crop also contributes to climate alteration. Simulation modelling and large data sets indicated the effects of climate change on OP will be to (a) reduce growth and yields and (b) cause death of some OP. Furthermore, basal stem rot (BSR) caused by Ganoderma boninense, a serious disease of OP, has increased over the past two or three decades because of the disease spreading from infection foci at a greater rate in repeated crops of OP planted on infested sites. The disease may increase further by natural selection of more virulent strains of the fungus. In this paper, increased mortality of OP is predicted based on climate change scenarios for Kalimantan and other South-East Asian countries with palm oil industries. Climate suitability scenarios for growing OP are also used to assess how BSR will change in the specified region and countries. The data suggest that Kalimantan and the Philippines may be more suitable for growing OP than Thailand and Myanmar, with Papua New Guinea being intermediate. Development of methods for mitigating the effects of climate change on OP is urgently required.
- Removal of a mixture of metal nanoparticles from natural surface waters using traditional coagulation processPublication . Serrão Sousa, Vânia; Ribau Teixeira, MargaridaEngineered nanoparticles (ENPs) present in natural water systems and wastewater treatment plants, due to their wide use in industrial products and consumer goods, represent a hazard to human health, especially if occur in surface waters used for human consumption. Different nanoparticles may co-exist in the natural waters and until now no works have been developed on the impact of the co-existing nanoparticles on water treatment processes. Thus, this work evaluates the removal of different co-existing metal-based ENPs (TiO2, Ag and CuO) from natural surface waters applying the most used water treatment process, coagulation/flocculation/sedimentation (C/F/ S). Results showed that C/F/S is effective in the removal of the co-existing ENPs from the studied hydrophilic natural waters (low/medium turbidity and moderate/moderate-high natural organic matter content) with efficiencies above 93% for TiO2, Ag and CuO nanoparticles. The formation of destabilised nanoparticle-organic matter aggregates in C/F promoted their precipitation. For the lowest turbidity and organic content water, Ti presented the lowest concentration, followed by Ag and Cu, because of titanium properties. For the highest turbidity and organic content water, the residual Cu concentration was the lowest and Ag the highest, due to the natural water characteristics. Water characteristics played an important role on the coagulant demand and removal of ENPs mixture by C/F/S. Results also demonstrated that ENPs mixture did not hampered the treated water quality for turbidity and natural organic matter. For the lowest turbidity and natural organic matter water, ENPs appear to contribute to a higher removal of these parameters.
- Effect of temperature on growth, photosynthesis and biochemical composition of Nannochloropsis oceanica, grown outdoors in tubular photobioreactorsPublication . Carneiro, M.; Cicchi, B.; Maia, I. B.; Pereira, H.; Zittelli, G. Chini; Varela, João; Xavier Malcata, F.; Torzillo, G.Since temperature is an important factor affecting microalgal growth, photosynthetic rate and biomass composition, this study has accordingly focused on its effects on biomass yield and nighttime biomass loss, as well as photochemical changes, using Nannochloropsis oceanica as model species, grown in two outdoor 50-L tubular photobioreactors (PBR). In two independent trials, cultures were subjected to a diurnal light:dark cycle, under a constant temperature of 28 degrees C and, on the second trial, at 18 degrees C. Changes in culture performance were assessed by measuring growth, lipid and fatty acid composition of the biomass in both morning and evening. Our results revealed that N. oceanica shows a wide temperature tolerance with relevant nighttime biomass loss, that decreased at lower temperatures, at the expenses of its daily productivity. Fluorescence measurements revealed reversible damage to photosystem II in cells growing in the PBR under optimal thermal conditions, whereas microalgae grown at suboptimal ones exhibited an overall lower photosynthetic activity. Lipids were partially consumed overnight to support cell division and provide maintenance energy. Eicosapentaenoic acid (EPA) catabolism reached a maximum after the dark period, as opposed to their saturated counterparts; whereas lower temperatures led to higher EPA content which reached the maximum in the morning. These findings are relevant for the production of Nannochloropsis at industrial scale.
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