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As the geometry of the swing-by maneuver greatly influences the outcome of the gain of energy and a possible escape trajectory, a study on the relative positioning between the Earth and the Moon is presented to define the conditions for the best transfers to the terrestrial planets of the solar system in the restricted four-body Sun–Earth–Moon–spacecraft Problem. At the start of the numerical simulation, a solar sail with loading of 164.7 g/m 2 is already deployed to conduct transfers towards Venus and Mars. [ABSTRACT FROM AUTHOR]

As the current phase of space exploration is marked by a rapidly growing number of rocket launches and space missions, techniques that would enable interplanetary missions at lower costs would also provide a more sustainable and affordable environment for space research. This paper introduces a strategy that combines the use of solar sails and lunar swing-bys to decrease the required increments of velocity ( Δ V ) to escape the Earth–Moon system to reach targets as far as Mars, in the Restricted Four-Body Sun–Earth–Moon–spacecraft Problem. Starting from a circular Low-Earth orbit, an increment of velocity (smaller than the one required to escape in a geocentric parabolic trajectory) is applied to the spacecraft and the solar sail is steered to maximize the gain of its orbital energy. This is done until the spacecraft performs a swing-by with the Moon. The use of this technique made it possible to reduce the Δ V by more than 98 % when compared to cases without the use of solar sails and lunar swing-bys. [ABSTRACT FROM AUTHOR]

The formation of our Solar System and planetary defense strategies are among the priorities to be investigated in the next years by the space science community. As in-situ missions to small bodies (as comets and asteroids) are options to conduct these investigations, this paper proposes a combination of methodologies to produce low-cost transfers to near-earth asteroids (NEAs). Low-cost trajectories derived from retrograde periodic orbits around L 1 are taken as a starting point for the escape of the Earth-Moon system and, as the vehicle exits the sphere of influence of Earth, the deployment of an adjustable solar sail guarantees the interception of the target in a predetermined position and time of flight. Different sail loadings (164, 61 and 30 g/m2) are tested and a case study to the NEA 65,803 Didymos is presented. The results show economies in the velocity increments required by the mission up to 8.48%, although a longer time of flight might be needed depending on the sail loading. [ABSTRACT FROM AUTHOR]

This study aimed to compare the physicochemical characteristics, fatty acid composition, and sensory attributes of the meat from three genetic groups: Nellore (Nell), ½ Nellore × ½ Angus (NeAn), and ¼ Nellore × ¼ Angus × ½ Senepol (NASe). Longissimus lumborum muscle from 30 slaughtered bulls with a body weight of 549 ± 32.5 kg was used. The water holding capacity was greater for the Nell and NeAn groups than for the NASe group. Meat samples from the NASe group exhibited a higher L* index than those from the NeAn group and lower a* and b* color indexes than those from the Nell group. The meat fatty acid profiles showed that the Nell group had higher concentrations of 12:0, 14:0, 18:1 t11, 14:1 c9, 16:1 c9, 18:1 c9, 18:1 c11, 18:2 c9, t11 (conjugated linoleic acid (CLA)), and 20:3 n-6 polyunsaturated fatty acid (PUFA) than the NeAn and NASe groups. The total saturated (ΣSFA), unsaturated (ΣUFA), and monounsaturated (ΣMUFA) fatty acid concentrations were higher and the ΣPUFA:ΣSFA ratio was lower in the Nell group than in the NeAn group. The Δ9–desaturase C16 activity was significantly higher in the Nell and NASe groups than in the NeAn group. The atherogenicity index (AI) tended to be lower in the crossbreeds than in the Nell breed. The NASe group presented meat with better tenderness, juiciness, and overall acceptance than the Nell and NeAn groups and was therefore the best genetic group for beef production of the tested groups. [ABSTRACT FROM AUTHOR]

Intervention programs have been developed to help parents cope with their child's cancer. Despite some studies reporting a high level of evidence, it is unclear how these programs build on each other. Appraising models of change is critical to advance scientific knowledge and provide evidence-based interventions. This review aims to identify existing programs, explicitly formulate their underlying models, evaluate how they translate into concrete activities, as well as identify and discuss their development process. Eleven programs based on models of change from cognitive-behavioral, systemic and counselling theories were identified. Many models included a sound theoretical framework, targeted outcomes, as well as implementation strategies. In most cases, preliminary development studies were conducted, but details were rarely provided on how development stages informed the redesign of intervention programs. Acceptability and treatment fidelity were not available for one-third of the programs. Future reports should document the development and design redesign stages prior to conducting efficacy trials, as this step would provide crucial details to critically appraise programs. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the impact of including licuri cake in the diet of Santa Inês crossbred finishing lambs by examining their liver metabolic and histopathological profile. Forty-four uncastrated lambs with an average age of 6 months and an average weight of 21.2 kg ± 2.7 kg. The animals were fed diets with 40 % Tifton 85 hay and 60 % of a mixture consisting of corn and soybean meal, 1 % urea, a mineral-vitamin premix, and an inclusion of licuri cake at a level of 0, 8, 16, and 24 % of the dietary dry matter (DM), which composed the treatments. The experimental design was completely randomized, and the data were analyzed by variance and regression analyses. The animals were confined in individual stalls for 70 days. Blood was collected on the last day of the experimental period, and metabolite, protein, energy, and enzyme profiles of the liver were determined for these samples. Histopathological evaluations of the liver parenchyma were also undertaken. The increase in the level of the licuri cake in the diet caused a linear increase ( P < 0.05) in the serum urea content. The protein metabolism was not affected by the licuri cake inclusion levels in the diet. Regarding energy metabolism, a linear increase ( P < 0.01) was observed in the serum triglyceride concentrations, but there were no effects on serum cholesterol levels. Regarding the functioning of the liver and muscle, the inclusion of the licuri cake had no effect on the enzymatic activities, except on gamma-glutamyltransferase, which decreased linearly ( P < 0.05). The values found for the evaluated parameters varied within a range considered normal for this species. In the postmortem examination at slaughter, no macroscopic alterations in the liver were observed. Histopathological analysis revealed the presence of discrete and nonspecific alterations common to all treatments, suggesting no effect of the level of inclusion of the licuri cake. The use of the licuri cake in composing up to 24 % of the diet did not cause metabolic or liver disorders in the lambs. [ABSTRACT FROM AUTHOR]