38 research outputs found

    Porous Superhydrophobic Membranes: Hydrodynamic Anomaly in Oscillating Flows

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    We have fabricated and characterized a novel superhydrophobic system, a mesh-like porous superhydrophobic membrane with solid area fraction Ī¦s\Phi_s, which can maintain intimate contact with outside air and water reservoirs simultaneously. Oscillatory hydrodynamic measurements on porous superhydrophobic membranes as a function of Ī¦s\Phi_s reveal surprising effects. The hydrodynamic mass oscillating in-phase with the membranes stays constant for 0.9ā‰¤Ī¦sā‰¤10.9\le\Phi_s\le1, but drops precipitously for Ī¦s<0.9\Phi_s < 0.9. The viscous friction shows a similar drop after a slow initial decrease proportional to Ī¦s\Phi_s. We attribute these effects to the percolation of a stable Knudsen layer of air at the interface.Comment: 5 pages, 3 figure

    Impact of a total mixed ration or pasture/pasture silage-based feeding strategy in the initial stages of lactation of spring-calving dairy cows on milk production, composition and selected milk processability parameters

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    peer-reviewedThe objective of this experiment was to investigate the effect of feeding strategy on milk production, composition and selected processability parameters in the initial stages of lactation. Twenty Holstein Friesian cows were allocated to one of two dietary treatments (n = 10; 7 multiparous and 3 primiparous) in a randomised complete block design for 21 d from day 10 to day 31 post-calving. Treatment 1 (pasture-based system [PBS]) was a pasture/pasture silage-based diet where cows were offered ad libitum grazed pasture or pasture silage (when weather did not permit grazing) plus 3 kg DM/d or 5 kg DM/d concentrate supplementation, respectively. On average, cows grazed pasture for 7.5 d and were fed pasture silage indoors for 13.5 d. Treatment 2 (TMR) was a total mixed ration (TMR) diet made up of concentrate, plus maize silage, pasture silage, beet pulp, soya bean meal and straw. Multiparous cows were blocked on calving date and balanced for parity and milk yield. Primiparous cows were balanced for live weight. Milk attributes pertinent to composition and functionality (e.g., fatty acids and rennet coagulation time [RCT]) were examined over a 21-d experimental period from day 10 to day 31 post-calving. Cows offered PBS tended to have a lower test day milk yield (PBS = 24.2 kg/cow vs. TMR = 26.8 kg/cow, P = 0.09) and a greater milk urea nitrogen (MUN) content compared to TMR (PBS = 0.030 g/100 g milk vs. TMR = 0.013 g/100 g milk, P < 0.001). Most notably, PBS-derived milks had a greater (P < 0.001) concentration of cis-9 trans-11 conjugated linoleic acid (CLA) compared to TMR. In conclusion, milk produced during early lactation from both feeding strategies was suitable for processing. Feeding a TMR compared with ad libitum pasture/pasture silage had no impact on average milk pH, casein concentration or RCT. Cows fed a pasture/pasture silage-based diet produced milk with a desirable RCT for milk processing, while the higher MUN content from cows offered PBS did not impact the processability of milk. Furthermore, milk from cows offered PBS had greater concentrations of cis-9 trans-11 CLA, which may offer human health benefits

    Vitamin D-biofortified beef: a comparison of cholecalciferol with synthetic versus UVB-mushroom-derived ergosterol as feed source

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    This study investigates dietary fortification of heifer feeds with cholecalciferol and ergocalciferol sources and effects on beef total vitamin D activity, vitamer, respective 25-hydroxymetabolite contents, and meat quality. Thirty heifers were allocated to one of three dietary treatments [(1) basal dietā€Æ+ā€Æ4000ā€ÆIU of vitamin D3 (Vit D3); (2) basal dietā€Æ+ā€Æ4000ā€ÆIU of vitamin D2 (Vit D2); and (3) basal dietā€Æ+ā€Æ4000ā€ÆIU of vitamin D2-enriched mushrooms (Mushroom D2)] for a 30ā€Æday pre-slaughter period. Supplementation of heifer diets with Vit D3 yielded higher (pā€Æā€Æ0.05) by the dietary treatments. In conclusion, vitamin D3 biofortification of cattle diets is the most efficacious way to enhance total beef vitamin D activity

    The use of synthetic and natural vitamin D sources in pig diets to improve meat quality and vitamin D content

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    This study investigated the effects of synthetic and natural sources of vitamin D biofortification in pig diets on pork vitamin D activity and pork quality. One hundred and twenty pigs (60 male, 60 female) were assigned to one of four dietary treatments for a 55ā€Æd feeding period. The dietary treatments were (1)50ā€ÆĪ¼g vitamin Dā‚ƒ/kg of feed; (2)50ā€ÆĪ¼g of 25-hydroxvitamin Dā‚ƒ/kg of feed (25-OH-Dā‚ƒ); (3)50ā€ÆĪ¼g vitamin Dā‚‚/kg of feed; (4)50ā€ÆĪ¼g vitamin Dā‚‚-enriched mushrooms/kg of feed (Mushroom Dā‚‚). The pigs offered the 25-OH-Dā‚ƒ diet exhibited the highest (Pā€Æ<ā€Æ0.001) serum total 25-hydroxyvitamin D concentration and subsequently exhibited the highest (Pā€Æ<ā€Æ0.05) Longissimus thoracis (LT) total vitamin D activity. Mushroom D2 and 25-OH-D3 supplementation increased pork antioxidant status. The vitamin Dā‚‚-enriched mushrooms improved (Pā€Æ<ā€Æ0.05) pig performance, carcass weight and LT colour. In conclusion, 25-OH-Dā‚ƒ is the most successful source for increasing pork vitamin D activity, while Mushroom D2 may be a new avenue to improve animal performance and pork quality

    Development of new microalgae-based sourdough "crostini": functional aspects of Arthrospira platensis (spirulina) addition

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    The aim of this work was to evaluate the influence of Arthrospira platensis F&M-C256 (spirulina) incorporation on the nutritional and functional properties of ā€œcrostiniā€, a leavened bakery product largely consumed in Italy and Europe. Sourdough was used as leavening and fermentation agent and three concentrations of A. platensis F&M-C256 were tested: 2%, 6% and 10% (w/w). Despite a lower volume increase compared to the control, the A. platensis F&M-C256 ā€œcrostiniā€ doughs reached a technological appropriate volume after fermentation. At the end of fermentation, no significant differences in microorganisms concentrations were observed. A. platensis F&M-C256 ā€œcrostiniā€ showed higher protein content compared to the control. Considering the European Commission Regulation on nutritional claims, ā€œcrostiniā€ incorporated with 6% and 10% biomass can be claimed to be a ā€œsource of proteinā€. Six and ten percent A. platensis ā€œcrostiniā€ also presented significantly higher antioxidant capacity and phenolics. A significantly lower value of in vitro dry matter and protein digestibility between A. platensis F&M-C256 ā€œcrostiniā€ and the control was found. The overall acceptability decreased with increasing A. platensis F&M-C256 addition. The combination of spirulina biomass addition and the sourdough technology led to the development of a novel microalgae-based bakery product with nutritional and functional featuresinfo:eu-repo/semantics/publishedVersio
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