25 research outputs found

    It Costs to Be Clean and Fit: Energetics of Comfort Behavior in Breeding-Fasting Penguins

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    ), seabirds known to fast for up to one month during incubation shifts ashore.A time budget was estimated from focal and scan sampling field observations and the energy cost of comfort activities was calculated from the associated increase in heart rate (HR) during comfort episodes, using previously determined equations relating HR to energy expenditure. We show that incubating birds spent 22% of their daily time budget in comfort behavior (with no differences between day and night) mainly devoted to preening (73%) and head/body shaking (16%). During comfort behavior, energy expenditure averaged 1.24 times resting metabolic rate (RMR) and the corresponding energy cost (i.e., energy expended in excess to RMR) was 58 kJ/hr. Energy expenditure varied greatly among various types of comfort behavior, ranging from 1.03 (yawning) to 1.78 (stretching) times RMR. Comfort behavior contributed 8.8–9.3% to total daily energy expenditure and 69.4–73.5% to energy expended daily for activity. About half of this energy was expended caring for plumage.This study is the first to estimate the contribution of comfort behavior to overall energy budget in a free-living animal. It shows that although breeding on a tight energy budget, king penguins devote a substantial amount of time and energy to comfort behavior. Such findings underline the importance of comfort behavior for the fitness of colonial seabirds

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

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    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

    Is territory defence related to plumage ornaments in the king penguin Aptenodytes patagonicus?

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    Colourful ornaments in monogamous birds may be directed at potential mates or other conspecifics to signal individual condition, reproductive status or fighting ability, especially in monogamous and territorial species. We investigated whether the size of the orange auricular patch may be an indicator of aggressiveness in the king penguin Aptenodytes patagonicus, a monogamous and territorial seabird. The relationship between auricular patch size and defence behaviour was explored relative to territory location (centre vs. periphery of the colony), period of reproduction (early vs. late), state of reproduction (incubation vs. brooding) and sex. The proportion of time spent in territorial defence and the rate of aggressive behaviours were positively correlated with auricular patch size, mainly because central birds were more aggressive than peripheral birds and also had larger patch sizes. The period of reproduction, state of reproduction and sex did not interact with patch size to affect aggressiveness. Our results suggest that the size of the auricular patch in king penguins may be a reliable signal allowing individuals to evaluate the quality of mates or competitors in terms of aggressiveness. Whether aggressiveness is directly linked to patch size or indirectly through body condition, however, remains to be determined. In any event, birds with larger patches seem to gain central territories in the colony, thereby increasing their reproductive success. Finally, our study adds to the growing evidence that the evolution of sexually monomorphic ornaments may stem from mutual sexual selection

    Heart rate increase during an episode of comfort behavior in an incubating king penguin.

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    <p>Shadowed zones delimit pre- and post-comfort resting periods and comfort behavior, respectively, whereas the white zone delimits the recovery period. Dotted lines give average HR during comfort behavior and recovery period, respectively, whereas the dashed lined gives average HR during pre- and post-comfort resting periods.</p

    Physicochemical Parameters, Phytochemical Profile and Antioxidant Properties of a New Beverage Formulated with Xique-Xique (Pilosocereus gounellei) Cladode Juice

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    This study elaborated different formulations with xique-xique (Pilosocereus gounellei) cladode, passion fruit and lime juice and sugar cane syrup. The formulated beverages were subjected to physical and physicochemical analysis, determination of total carotenoid, total flavonoid and total phenolic compound contents, as well as of their antioxidant activity (ABTS and FRAP method), organic acid, sugar and phenolic compound profile during 21 days of refrigeration storage (4 °C). Significant variations were found among formulated beverages for most of the measured parameters during storage. Beverages with xique-xique juice were less acidic (7.90–10.27 g/100 mL) than beverages without this juice (11.66–12.76 g/100 mL). Beverages with xique-xique juice had overall higher contents of bioactive compounds and higher antioxidant activity when compared to the control formulation. Beverages with the highest xique-xique juice concentrations had the highest contents of carotenoids (51.51–59.27 µg/100 mL), flavonoids (1.39–2.15 mg CE/100 mL), phenolic compounds (68.49–115.66 mg EGA/100 mL) and antioxidant activity, as measured by ABTS (0.71–0.84 µmol Trolox/mL) and FRAP (0.33–0.39 µmol Trolox/mL). These results indicate that the incorporation of xique-xique cladode juice in these mixed beverages enhanced their bioactive properties, especially of antioxidant compounds, enabling the development of a new product with potential functional properties to the beverage industry

    Physical, Nutritional, and Bioactive Properties of Mandacaru Cladode Flour (<i>Cereus jamacaru</i> DC.): An Unconventional Food Plant from the Semi-Arid Brazilian Northeast

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    In this study, we evaluated the physical, nutritional, and bioactive properties of mandacaru cladode flour (Cereus jamacaru DC.). The granulometric profile revealed particles with non-uniform geometry, flakiness, a rectangular tendency, and a non-homogeneous surface, with particle sizes ranging from 20 to 60 µm. The flour presented low water activity (0.423), a moisture content of 8.24 g/100 g, high ash (2.82 g/100 g), protein (5.18 g/100 g), and total carbohydrate contents (74.48 g/100 g), and low lipid contents (1.88 g/100 g). Mandacaru flour is an excellent source of insoluble dietary fiber (48.08 g/100 g), calcium (76.33%), magnesium (15.21%), and potassium (5.94%). Notably, 1H NMR analysis revealed the presence of N-methyltyramine. Using HPLC chromatography, glucose was identified as the predominant sugar (1.33 g/100 g), followed by four organic acids, especially malic acid (9.41 g/100 g) and citric acid (3.96 g/100 g). Eighteen phenolic compounds were detected, with relevant amounts of kaempferol (99.40 mg/100 g), myricetin (72.30 mg/100 g), and resveratrol (17.84 mg/100 g). The total phenolic compounds and flavonoids were 1285.47 mg GAE/100 g and 15.19 mg CE/100 g, respectively. The mean in vitro antioxidant activity values were higher using the FRAP method (249.45 µmol Trolox TEAC/100 g) compared to the ABTS•+ method (0.39 µmol Trolox TEAC/g). Finally, the ascorbic acid had a content of 35.22 mg/100 g. The results demonstrate the value of mandacaru as a little-explored species and an excellent matrix for the development of flours presenting good nutritional value and bioactive constituents with excellent antioxidant potential

    Analysis of parasite reduction ratio at 48 h (PRR<sub>48h</sub>).

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    <p>Evaluation of PRR<sub>48h</sub> allowed validation of the <i>Plasmodium berghei</i> ED<sub>90</sub>-normalized in vivo assay in vehicle-treated control animals and against human data. (A) Correlation between the log<sub>10</sub> [PRR<sub>48h</sub>] and the distance between top and bottom values of the logistic fit calculated in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0066967#pone-0066967-g004" target="_blank">Figure 4</a> for each control antimalarial in CD1 mice infected with <i>P. berghei</i>. (B) Correlation of log<sub>10</sub> [PRR<sub>48h</sub>] between CD1 mice infected with <i>P. berghei</i> in the screening assay format and humans infected with <i>P. falciparum</i>. Data on log<sub>10</sub> [PRR<sub>48h</sub>] in humans are taken from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0066967#pone.0066967-Anvikar1" target="_blank">[30]</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0066967#pone.0066967-Sanz1" target="_blank">[32]</a>.</p
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