Legume and Nitrogen Fertilization Affect Animal Performance and Enteric Methane Emission of Nellore Heifers

Methane emission from livestock operation is an important source of greenhouse gas and contributes to global warming. Forage legume secondary compounds may mitigate methane emissions by reducing methanogenic population in the rumen. This study evaluated animal performance and methane emission from beef cattle grazing either a mixed pasture [Brachiaria brizantha cv. Marandu (palisadegrass) and Arachis pintoi (forage peanut) cv. BRS Mandobi] or a palisadegrass monoculture with or without nitrogen (N) fertilisation. A 2.5-yr continuous stocking experiment was carried out in southeast Brazil, on a randomized complete block design with three treatments and four replicates. Two Nellore heifers were used as tester animals and additional put-and-takes were used to keep canopy height at 20-25 cm. The treatments comprised three pasture types: 1) palisadegrass-forage peanut mixed pasture (GRASS+LEGUME); 2) palisadegrass + 150 kg N/ha/year (GRASS+N); 3) palisadegrass without N fertilization (GRASS). Response variables included average daily gain (ADG), forage intake, and methane emission. Methane emission was estimated by the sulphur hexafluoride (SF6) tracer technique. There was no difference between grazing systems for the ADG (P = 0.439) and DMI (P = 0.394; averages of 0.433 kg/d and 2.10 %BW/d, respectively). In the GRASS+LEGUME, there was a decrease of 11.7% in methane emission per animal (148 vs. 170 and 165 g/day for GRASS+N and GRASS, respectively; P = 0.001). Grazing systems including legume reduced methane emission per unit of ADG (365 vs. 428 and 398 g/kg for GRASS and GRASS+N, respectively; P = 0.061) and per carcass gain (656 vs. 800 g of methane/kg carcass for GRASS; P = 0.022). Intake of condensed tannins was greater for GRASS+LEGUME (0.61 vs. 0.17 %BW/d, P \u3c 0.001). Forage peanut decreased enteric methane emission intensity, reducing carbon footprint of livestock systems in Southeast Brazil

How Does N Fertilization or Forage Legumes Affect Forage and Animal Production?

Livestock grazing in tropical climates is characterized by low productivity. Forage and animal production can be improved by applying nitrogen (N) fertiliser or using forage legumes. This 2.5-yr study assessed the canopy structure and productivity of beef cattle grazing either a mixed pasture of Brachiaria brizantha cv. Marandu (palisadegrass) and Arachis pintoi (forage peanut) cv. BRS Mandobi or a Marandu palisade grass monoculture with or without N fertilisation. The experiment was carried out in Southeast Brazil, where the canopy structure (herbage mass) and animal productivity (stocking rate and liveweight gain per ha) were compared for three types of pastures: 1) mixed pasture of Marandu palisade grass and forage peanut (GRASS+LEGUME); 2) a monoculture of Marandu palisadegrass fertilised with 150 kg N/ha/year (GRASS+N); and 3) monoculture of Marandu palisadegrass without N application (GRASS), under continuous stocking. A minimum of two Nellore heifers and additional put-and-takes were used to keep canopy height at 20-25 cm. A randomized complete block design was used with four replicates; seasons were considered repeated measurements over time. Herbage mass was greater in the GRASS+N pasture (P \u3c 0.001); however, in the last three seasons (Spring II, Summer III, and Fall III), there was no difference to GRASS+LEGUME pasture. In the GRASS+LEGUME pasture, there was an increase of legume mass (1.260 to 2.565 kg/ha) and botanical composition (23.6 to 39.1% of legume in forage mass) throughout the study. The stocking rate (P \u3c 0.001) and liveweight gain per ha (P \u3c 0.001) were greater in GRASS+N, without difference among GRASS+LEGUME and GRASS pastures in the first seven seasons. In the last three seasons, with an increase of legume proportion, stocking rate and liveweight were intermediate for GRASS+LEGUME pasture. Legume increased herbage mass and animal productivity in the long term. Immediate responses were achieved with N fertilization

Teaching Sciences in Virtual Worlds with Mastery Learning: A Case of Study in Elementary School

Virtual worlds are 3D environments that provide a feeling of immersion and a high degree of interaction, collaboration, communication between users. Its applicability can be focused on the educational scope, in which theories can be integrated as the basis to didactic activities carried out in the 3D environment, being its area of interdisciplinary comprehension. In this context, this article presents the use of a Virtual World built to assist in the teaching of Science for students of the middle school, whose articulation of the activities performed in the course are based on the precepts of the educational theory Mastery Learning. Tests were carried out in the subject of science, being divided into two periods with different groups for comparative purposes and realized evaluations during the period of the experiments. Kruskal-Wallis and Wilcoxon-Mann-Whitney non-parametric test were applied to the results of the assessments to ascertain the performance of each group. It was verified in the general analyzis that the participants who used the Virtual World had a growing performance, with high medians and adequate distribution of the results, being predominant of a smaller variability and amplitude. Thus, was possible to conclude that the results obtained with the approach were positive, which led to the validation of this research and presented a clear contribution to the academic environment

Mais-valia nutricional de macroalgas marinhas dos Açores. Determinação do teor de fibra bruta.

IV Congresso da Ordem dos Biólogos e II Congresso dos Biólogos dos Açores (Painel Biologia Marinha e Oceanografia). Ponta Delgada, Açores, 13-15 de Outubro de 2011

An explanation for the interaction mechanism of an anionic polymeric additive on yeast flocculent cells

Magna Floc LT25 is a high molecular weight anionic polymer that has been described as increasing reaction rates inside flocs of yeast cells. However, no clear indication has been given on how this anionic polymer interacts with flocculent cells. Flocculation experiments made with a strain ofSaccharomyces cerevisiae corroborate that it bridges calcium ions bound to flocculent yeast cell walls, thus enlarging the available flux area for the transport of solutes inside the flocs

Production and characterization of protease from Penicillium aurantiogriseum URM 4622

Proteases with new properties are required due to their increasing industrial importance. In this work, the optimal fermentation conditions for the production of a protease from Penicillium aurantiogriseum dierchx (URM-4622) are presented together with partial characterization of the protease catalytic properties. The batch fermentation conditions that allow for the highest specific proteolytic activity are 26 ºC, pH 7.0, and 25 % saturation dissolved O2 concentration. The obtained protease is stable over a wide range of pH (5.8 to 9.5) and temperature (25 to 40 ºC) values. In the presence of Zn2+ a 26 % reduction in the enzyme proteolytic activity occurs and, in contrast, Mn2+ enhances its activity by 28.9 %. 96.2 % and 70.8 % of the protease activity are maintained after 90 min incubation in 5 and 10 % (v/v) H2O2 aqueous solutions, respectively. PMSF inhibition reveals that this enzyme is a serine protease. Protease is able to hydrolyze different proteins

Targeting p53 for melanoma treatment: counteracting tumour proliferation, dissemination and therapeutic resistance

Melanoma is the deadliest form of skin cancer, primarily due to its high metastatic propensity and therapeutic resistance in advanced stages. The frequent inactivation of the p53 tumour suppressor protein in melanomagenesis may predict promising outcomes for p53 activators in melanoma therapy. Herein, we aimed to investigate the antitumor potential of the p53-activating agent SLMP53-2 against melanoma. Two- and three-dimensional cell cultures and xenograft mouse models were used to unveil the antitumor activity and the underlying molecular mechanism of SLMP53-2 in melanoma. SLMP53-2 inhibited the growth of human melanoma cells in a p53-dependent manner through induction of cell cycle arrest and apoptosis. Notably, SLMP53-2 induced p53 stabilization by disrupting the p53–MDM2 interaction, enhancing p53 transcriptional activity. It also promoted the expression of p53-regulated microRNAs (miRNAs), including miR-145 and miR-23a. Moreover, it displayed anti-invasive and antimigratory properties in melanoma cells by inhibiting the epithelial-to-mesenchymal transition (EMT), angiogenesis and extracellular lactate production. Importantly, SLMP53-2 did not induce resistance in melanoma cells. Additionally, it synergized with vemurafenib, dacarbazine and cisplatin, and resensitized vemurafenib-resistant cells. SLMP53-2 also exhibited antitumor activity in human melanoma xenograft mouse models by repressing cell proliferation and EMT while stimulating apoptosis. This work discloses the p53-activating agent SLMP53-2 which has promising therapeutic potential in advanced melanoma, either as a single agent or in combination therapy. By targeting p53, SLMP53-2 may counteract major features of melanoma aggressiveness.This work received financial support from PT national funds (FCT/MCTES, Fundação para a Ciência e Tecnologia and Ministério da Ciência, Tecnologia e Ensino Superior) through LAQV/REQUIMTE (UID/QUI/50006/2020), iMed.ULisboa (UIDB/04138/2020), and PTDC/QUIQOR/29664/2017, PTDC/MEC-ONC/32018/2017. We thank FCT for the fellowships SFRH/BD/ 128673/2017 (J. Loureiro), 2020.04613.BD (J. Calheiros), PD/BD/143126/2019 (V. Barcherini)

Scaling solutions from interacting fluids

We examine the dynamical implications of an interaction between some of the fluid components of the universe. We consider the combination of three matter components, one of which is a perfect fluid and the other two are interacting. The interaction term generalizes the cases found in scalar field cosmologies with an exponential potential. We find that attracting scaling solutions are obtained in several regions of parameter space, that oscillating behaviour is possible, and that new curvature scaling solutions exist. We also discuss the inflationary behaviour of the solutions and present some of the constraints on the strength of the coupling, namely those arising from nucleosynthesis.Comment: RevTeX, 21 pages, 8 figure

Alpinia

Species of the genus Alpinia are widely used by the population and have many described biological activities, including activity against insects. In this paper, we describe the bioactivity of the essential oil of two species of Alpinia genus, A. zerumbet and A. vittata, against Rhodnius nasutus, a vector of Chagas disease. The essential oils of these two species were obtained by hydrodistillation and analyzed by GC-MS. The main constituent of A. zerumbet essential oil (OLALPZER) was terpinen-4-ol, which represented 19.7% of the total components identified. In the essential oil of A. vittata (OLALPVIT) the monoterpene β-pinene (35.3%) was the main constituent. The essential oils and their main constituents were topically applied on R. nasutus fifth-instar nymphs. In the first 10 min of application, OLALPVIT and OLALPZER at 125 μg/mL provoked 73.3% and 83.3% of mortality, respectively. Terpinen-4-ol at 25 μg/mL and β-pinene at 44 μg/mL provoked 100% of mortality. The monitoring of resistant insects showed that both essential oils exhibited antifeedant activity. These results suggest the potential use of A. zerumbet and A. vittata essential oils and their major constituents to control R. nasutus population