171 research outputs found
Development of sulfur based polymers for rechargeable lithium batteries
Lithium-ion (Li-ion) batteries are in the front edge of recent achievements concerning energy storage.
However, Li-ion devices are reaching their maximum regarding energy density storage which restricts their
appiicatÃon in systems with large power needs, such as electric vehicles. Driven by this shortcoming, in the
last few years, Lithium-Sulfur (Li-S) batteries are being considered as an alternative for the exploitatÃon of
energy storage and conversion systems with improved performance. Indeed, to the S cathodes is associated
a theoretical specifÃc capacity of 1672 mA h g-1 and a specifÃc energy of 2600 W h kg-\ which are several
times higher than the correspondent to other possible systems. The relative low atomic weight of S in
comparison with other elements (e.g. cobalt) and the multÃ-electron transfer reactÃons in the pair Li/S are at
the source ofthis superior theoretÃcal performance of Li-S batteries.Este trabalho foi financiado por: projeto POCI-01-0145-FEDER-006984 - Laboratório Associado LSRE-LCM - financiado pelo Fundo Europeu de Desenvolvimento Regional (FEDER), através do COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI)info:eu-repo/semantics/publishedVersio
Somatotype is more interactive with strength than fat mass and physical activity in peripubertal children
The purpose of this study was to analyse the interaction between somatotype, body fat and physical activity in
prepubescent children. This was a cross!sectional study design involving 312 children (160 girls, 152 boys) aged
between 10 and 11.5 years old (10.8 ± 0.4 years old). Evaluation of body composition was done determining body mass
index and body fat by means of skin!fold measurements, using the method described by Slaughter. Somatotype was
computed according to the Carter’s method. Physical activity was assessed with the Baecke questionnaire. The physical
activity assessment employed sets of curl!ups, push!ups, standing broad jump, medicine ball throw, handgrip strength
and Margaria!Kalamen power stair. There were negative associations for body fat, endomorphy and mesomorphy with
curl!ups, push!ups and broad jump tests and positive associations with ball throw, handgrip strength and Margaria!
Kalamen power tests. The associations for ectomorphy were the inverse of those for endomorphy and mesomorphy. Non
obese children presented higher values for curl!ups, push!ups and standing broad jump. In medicine ball throw,
handgrip strength and Margaria!Kalamen power test obese children presented higher scores, followed by children who
were overweight. The mesoectomorphic boys and ectomesomorphic girls performed higher in all tests. The morphological
typology presented more interactions with strength than % of body fat and physical activity. These data seem to suggest
that the presence/absence of certain physical characteristics is crucial in the levels of motor provision in prepubescent
children
Current knowledge and future perspectives of the use of seaweeds for livestock production and meat quality : a systematic review
Research Areas: Agriculture ; Veterinary SciencesABSTRACT - The effects of dietary macroalgae, or seaweeds, on growth performance and meat quality of livestock animal species are here reviewed. Macroalgae are classified into Phaeophyceae (brown algae), Rhodophyceae (red algae) and Chlorophyceae (green algae). The most common macroalga genera used as livestock feedstuffs are: Ascophyllum, Laminaria and Undaria for brown algae; Ulva, Codium and Cladophora for green algae; and Pyropia, Chondrus and Palmaria for red algae. Macroalgae are rich in many nu-trients, including bioactive compounds, such as soluble polysaccharides, with some species being good sources of n-3 and n-6 polyunsaturated fatty acids. To date, the in-corporation of macroalgae in livestock animal diets was shown to improve growth and meat quality, depending on the alga species, dietary level and animal growth stage. Generally, Ascophyllum nodosum can increase average daily gain (ADG) in ruminant and pig mostly due to its prebiotic activity in animal's gut. A. nodosum also enhances marbling score, colour uniformity and redness, and can decrease saturated fatty acids in ruminant meats. Laminaria sp., mainly Laminaria digitata, increases ADG and feed efficiency, and improves the antioxidant potential of pork. Ulva sp., and its mixture with Codium sp., was shown to improve poultry growth at up to 10% feed. Therefore, seaweeds are promising sustainable alternatives to corn and soybean as feed ingre-dients, thus attenuating the current competition among food-feed-biofuel industries. In addition, macroalgae can hinder eutrophication and participate in bioremediation. However, some challenges need to be overcome, such as the development of large- scale and cost-effective algae production methods and the improvement of algae digestibility by monogastric animals. The dietary inclusion of Carbohydrate-Active enZymes (CAZymes) could allow for the degradation of recalcitrant macroalga cell walls, with an increase of nutrients bioavailability. Overall, the use of macroalgae as feedstuffs is a promising strategy for the development of a more sustainable livestock production.info:eu-repo/semantics/publishedVersio
Impact of dietary Chlorella vulgaris and carbohydrate-active enzymes incorporation on plasma metabolites and liver lipid composition of broilers
Research Areas: Veterinary SciencesBackground: Chlorella vulgaris has been proposed as a sustainable green feedstock in poultry nutrition due to its ease of cultivation, minimal environmental impact and balanced nutritional composition. However, the majority of studies documents the use of C. vulgaris as a dietary supplement in broilers instead of a feed ingredient. To the best of our knowledge, no report has shown the effect of a high-level incorporation (>2 % in the diet) of C. vulgaris on plasma metabolites and hepatic lipid composition of broilers. One hundred and twenty Ross 308 male birds were housed in 40 wired-floor cages and randomly distributed by the following experimental diets at 22 days of age (n = 10) during 15 days: (1) a corn-soybean meal based diet (control); (2) based diet with 10% of C. vulgaris; (3) diet 2 supplemented with 0.005% Rovabio® Excel AP; and (4) diet 2 supplemented with 0.01% of a pre-selected four-CAZyme mixture. Results: The inclusion of C. vulgaris at 10% in the diet, regardless of the presence of exogenous CAZymes, changed plasma metabolites but did not compromise broilers growth. Plasma total lipids increased in broilers fed C. vulgaris combined with the two feed CAZymes (p < 0.001) compared with the control diet. Moreover, the supplementation with Rovabio® increased total cholesterol and LDL-cholesterol, while the addition of the four-CAZyme mixture increased triacylglycerols, VLDL-cholesterol and ALP activity. In opposition, HDL-cholesterol levels decreased in broilers fed microalga alone (p = 0.002). Regarding hepatic composition, the inclusion of C. vulgaris in broiler diets, individually or combined with exogenous CAZymes, had a minor effect on fatty acids but improved the n-6/n-3 ratio and total carotenoids.
Conclusions: In summary, the inclusion of a high level (10%) of C. vulgaris in broiler´s diet, regardless of the presence of exogenous CAZymes, improved hepatic antioxidant composition and did not impair broiler’s performance. In addition, the feed supplementation with CAZymes increased broilers lipemia. Therefore, dietary C. vulgaris at this incorporation level seems to be safe for animal health and do not compromise performance traits, with no need of CAZymes supplementation.info:eu-repo/semantics/publishedVersio
An individual alginate lyase is effective in the disruption of Laminaria digitata recalcitrant cell wall
Research Areas: Science & Technology - Other TopicsIn the present study, 199 pre-selected Carbohydrate-Active enZymes (CAZymes) and sulfatases were
assessed, either alone or in combination, to evaluate their capacity to disrupt Laminaria digitata cell
wall, with the consequent release of interesting nutritional compounds. A previously characterized
individual alginate lyase, belonging to the family 7 of polysaccharide lyases (PL7) and produced
by Saccharophagus degradans, was shown to be the most efcient in the in vitro degradation of L.
digitata cell wall. The alginate lyase treatment, compared to the control, released up to 7.11 g/L
of reducing sugars (p< 0.001) and 8.59 mmol/100 g dried alga of monosaccharides (p< 0.001), and
reduced cell wall fuorescence intensity by 39.1% after staining with Calcofuor White (p= 0.001). The
hydrolysis of gel-forming polymer alginate by the alginate lyase treatment could prevent the trapping
of fatty acids and release benefcial monounsaturated fatty acids, particularly 18:1c9 (p < 0.001), to
the extracellular medium. However, no liberation of proteins (p > 0.170) or pigments (p > 0.070) was
observed. Overall, these results show the ability of an individual alginate lyase, from PL7 family, to
partially degrade L. digitata cell wall under physiological conditions. Therefore, this CAZyme can
potentially improve the bioavailability of L. digitata bioactive compounds for monogastric diets, with
further application in feed industry.info:eu-repo/semantics/publishedVersio
Effect of Dietary Laminaria digitata with Carbohydrases on Broiler Production Performance and Meat Quality, Lipid Profile, and Mineral Composition
Research Areas: Agriculture; Veterinary Sciences; ZoologyABSTRACT - We hypothesized that dietary inclusion of 15% Laminaria digitata, supplemented or not with carbohydrases, could improve the nutritional value of poultry meat without impairing animal growth performance. A total of 120 22-day old broilers were fed the following dietary treatments (n = 10) for 14 days: cereal-based diet (control); control diet with 15% L. digitata (LA); LA diet with 0.005% Rovabio® Excel AP (LAR); LA diet with 0.01% alginate lyase (LAE). Final body weight was lower and feed conversion ratio higher with LA diet than with the control. The ileal viscosity increased with LA and LAR diets relative to control but without differences between LAE and control. The pH of thigh meat was higher, and the redness value of breast was lower with LA diet than with control. Meat overall acceptability was positively scored for all treatments. The γ-tocopherol decreased, whereas total chlorophylls and carotenoids increased in meat with alga diets relative to control. The percentage of n-3 polyunsaturated fatty acids (PUFA) and accumulation of bromine and iodine in meat increased with alga diets compared with control. Feeding 15% of L. digitata to broilers impaired growth performance but enhanced meat quality by increasing antioxidant pigments, with beneficial effects on n-3 PUFA and iodineinfo:eu-repo/semantics/publishedVersio
Gota úrica visceral em coruja suindara (Tyto alba) de vida livre
A gota úrica é uma doença metabólica caracterizada pela deposição de cristais de urato e ácido úrico em tecidos do corpo, que pode acometer répteis, mamÃferos e aves. Neste trabalho, relata-se um caso de achados post mortem compatÃveis com gota úrica visceral em um exemplar de coruja suindara (Tyto alba) de vida livre. Macroscopicamente, o pericárdio apresentava-se completamente esbranquiçado, espesso e aderido ao miocárdio e o fÃgado e ambos os rins apresentavam áreas esbranquiçados sugerindo acúmulo de urato. A microscopia do tecido cardÃaco e hepático revelou pericardite fibrinosa e perihepatite necrosante respectivamente. Congestão pulmonar e infiltrado inflamatório heterofÃlico multifocal no parênquima renal também foram visualizados. As alterações encontradas são compatÃveis com as descritas na literatura para gota úrica visceral em aves, podendo até serem consideradas como lesões patognomônicas. Este é o primeiro relato de gota úrica visceral em um rapinante de vida livre no Brasil
- …