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Browsing EM - Artigos Científicos by Field of Science and Technology (FOS) "Ciências Naturais"
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- Assessing harbour porpoise carcasses potentially subjected to grey seal predationPublication . van Neer, Abbo; Gross, Stephanie; Kesselring, Tina; Grilo, Miguel L.; Ludes-Wehrmeister, Eva; Roncon, Giulia; Siebert, UrsulaAs a follow-up on the data presented for seals, we herein report and discuss outcomes resulting from a retrospective evaluation of harbour porpoise stranding and necropsy data from Schleswig–Holstein, Germany (n = 4463) to enable an objective evaluation of potential ecological effects of grey seal predation on porpoises. Results are compared to a recent case of definite grey seal predation as well as to reports from other countries. Porpoise carcasses potentially subject to grey seal predation show severe lacerations, with large parts of skin and underlying tissue being detached from the body. Loss of blubber tissue is common. Based on the occurrence frequencies of encountered lesions, a list of parameters as well as a complementary decision tree are suggested to be used for future assessments. The results shown add to an increasingly standardised assessment protocol of suspected grey seal predation cases making respective results comparable between different areas and countries. The usage of a standardised protocol may increase the awareness of grey seal predation and the reporting of such cases. By this, differences in the predation and feeding patterns as well as the potential ecological relevance of this behaviour may be elucidated.
- Black soldier fly - an invaluable weapon in the war for the sustainability of the agrarian economy and defense of the environmentPublication . Menino, Regina; Murta, DanielThe growing demographic pressure, worldwide, has been alerting our planet, in an increasingly alarming way, to a progressive food deficit and a growing degradation of the quality of the environment; thus, the urgent need for new alternatives for agricultural production (among others) has been revealing the potential of insects in the two aspects mentioned above. In this context, the black soldier fly has revealed an invaluable potential for the biological composting of the remnants of agricultural production, with the triple objective of eliminating potentially polluting products, producing food for livestock farming and producing organic fertilizers capable of competing with chemical fertilizers, without the harmful effects of the latter, and with a high potential for the sustainability of the productivity of agricultural soils. The present communication, based on the advances that scientific experimentation has shown in this area, intends to highlight the high potential of this dipteran in the desideratum in question, particularly in the context of a circular economy.
- Cattle effluents, either composted or bio-digested by Black Soldier Fly larvae, in the fertilization of ryegrass in sandy soilsPublication . Menino, Regina; Lopes, Ivã; Semedo, José N.; Scotti-Campos, Paula; Murta, Daniel; Castelo-Branco, Amélia; Nestler, Cecília; Moreira, OlgaThe relative agronomic performance of two organic fertilizers - effluents from intensive cattle farming, after composting either by traditional aerobic methods (compost) or by bio-digestion by larvae of the black soldier fly (Hermetia illucens, BSF) (frass) - in the growth of annual ryegrass (Lolium multiflorum L.) on a sandy soil was evaluated. For this purpose, a pot trial was conducted in a semi-controlled greenhouse. Eight treatments were defined, with four treatments using the compost and four treatments using frass (with a 10% nitroamoniacal nitrogen supplementation in all treatments), in addition to a negative control without fertilization, and a positive control with exclusively chemical nitroamoniacal fertilization. Regarding the biomass production, the BSF frass displayed a higher potential than the compost, with a significantly higher production from an N endowment equivalent to 280 kg ha-1 (252 kg organic N + 28 kg mineral N). While the yields obtained with compost were stable when 350 kg ha-1 (315 kg organic N + 35 kg mineral N) were provided, the yields obtained with BSF frass revealed a tendency to continue to progress with higher doses. This could be justified by the fact that the P2O5 and K2O content of BSF frass is significantly higher than that of the compost, and these nutrients continued to be mineralized over time. Furthermore, the obtained results confirm the potentiating effect of mineral fertilizers in the maximization of biomass production, when associated with organic fertilizers in adequate proportions. In addition, it was verified that the addition of frass enhanced the water use by plants, which was significantly higher than the treatments with compost, regardless of the N endowment. It was concluded that mixing chemical and organic fertilizers positively impacts soil fertility and the sustainability of the production as a whole, by increasing productivities in a sustainable way.
- An evaluation of portuguese societal opinion towards the practice of bullfightingPublication . Diéguez, Francisco Javier; Zau, Yara; Viegas, Inés; Fragoso, Sara; Turner, Patricia V.; Graça-Pereira, Gonçalo daBullfighting is a controversial sport that continues to be legally permitted in a number of countries around the world, including Portugal. The spectacle has attracted significant attention from animal protectionist groups for many years because of concerns for animal distress, pain, and suffering during the fights. While there has been strong support for the sport in Portugal in the past, there is a need to study social profiles regarding the acceptability of this sport before a case can be made for changes in regional and national legislation. In this study, Portuguese attendance patterns at bullfights were assessed in addition to public opinions on welfare and ethical aspects of bullfighting, based on demographic variables. Study participants (n = 8248) were largely recruited through Portuguese social media channels (respondents may not be representative of the Portuguese population). Questionnaire data were evaluated by means of frequency tables, multiple correspondence analyses, and a two-step cluster analysis. Most respondents had a negative opinion about bullfighting and perceived that bullfighting had no positive impact on the country. However, while most respondents thought that the bull suffered during bullfighting, the opinion regarding banning bullfighting was far from unanimous. Based on the demographic analysis, the profile of individuals with more favorable responses towards bullfighting were men > 65 years old, of Roman Catholic faith, of low- or high-income levels, from more rural areas of Portugal. Somewhat surprisingly, there was a tendency to favor bullfighting amongst veterinary professionals. We conclude that there were still large pockets of individuals who desire to maintain the practice of traditional bullfighting within Portuguese society, despite recognition of animal suffering during the event.
- Physical and morphological characterization of chitosan/montmorillonite films incorporated with ginger essential oilPublication . Souza, Victor Gomes Lauriano; Pires, João Ricardo Afonso; Rodrigues, Carolina; Rodrigues, Patricia Freitas; Lopes, Andréia; Silva, Rui Jorge; Caldeira, Jorge; Duarte, Maria Paula; Fernandes, Francisco Braz; Coelhoso, Isabel Maria; Fernando, Ana LuisaNovel bionanocomposite films of chitosan/montmorillonite (CS/MMT) activated with ginger essential oil (GEO) were produced and characterized in terms of their physical and morphological properties. The homogenization process led to a good interaction between the chitosan and the nanoparticles, however the exfoliation was diminished when GEO was incorporated. Film glass transition temperature did not statistically change with the incorporation of either MMT or GEO, however the value was slightly reduced, representing a relaxation in the polymer chain which corroborated with the mechanical and barrier properties results. Pristine chitosan films showed excellent barrier properties to oxygen with a permeability of 0.184 × 10−16 mol/m·s·Pa being reduced to half (0.098 × 10−16 mol/m·s·Pa) when MMT was incorporated. Although the incorporation of GEO increased the permeability values to 0.325 × 10−16 mol/m·s·Pa when 2% of GEO was integrated, this increment was smaller with both MMT and GEO (0.285 × 10−16 mol/m·s·Pa). Bionanocomposites also increased the UV light barrier. Thus, the produced bioplastics demonstrated their ability to retard oxidative processes due to their good barrier properties, corroborating previous results that have shown their potential in the preservation of foods with high unsaturated fat content.
- A quasi-reagentless point-of-care test for nitrite and unaffected by oxygen and cyanidePublication . Monteiro, Tiago; Gomes, Sara; Jubete, Elena; Añorga, Larraitz; Silveira, Célia M.; Almeida, Maria GabrielaThe ubiquitous nitrite is a major analyte in the management of human health and environmental risks. The current analytical methods are complex techniques that do not fulfil the need for simple, robust and low-cost tools for on-site monitoring. Electrochemical reductase-based biosensors are presented as a powerful alternative, due to their good analytical performance and miniaturization potential. However, their real-world application is limited by the need of anoxic working conditions, and the standard oxygen removal strategies are incompatible with point-of-care measurements. Instead, a bienzymatic oxygen scavenger system comprising glucose oxidase and catalase can be used to promote anoxic conditions in aired environments. Herein, carbon screen-printed electrodes were modified with cytochrome c nitrite reductase together with glucose oxidase and catalase, so that nitrite cathodic detection could be performed by cyclic voltammetry under ambient air. The resulting biosensor displayed good linear response to the analyte (2–200 µM, sensitivity of 326 ± 5 mA M−1 cm−2 at −0.8 V; 0.8–150 µM, sensitivity of 511 ± 11 mA M−1 cm−2 at −0.5 V), while being free from oxygen interference and stable up to 1 month. Furthermore, the biosensor’s catalytic response was unaffected by the presence of cyanide, a well-known inhibitor of heme-enzymes.