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The recent agricultural expansion in the Matopiba region, Brazil's new agricultural frontier, has raised questions about the risk of increasing soil organic carbon (SOC) loss as large areas of native vegetation (NV; i.e., Cerrado biome) have been replaced by large-scale mechanized agriculture. Although sustainable managements, such as integrated crop-livestock (ICL) systems, are considered strategic to counterbalance the SOC loss associated with land-use change (LUC) while keeping food production, little is known about their long-term effects on SOC stocks in the Matopiba region. To this end, we used the DayCent model to simulate the effects of converting the management commonly used in this region, i.e., soybean-cotton rotation under no-tillage (NT), into ICL systems with distinct levels of intensification (e.g., crop rotations: soybean-pasture and soybean-pasture-cotton; soil and crop management: grass irrigation, scarification/harrowing, and length of grass cultivation) on long term SOC dynamics. Additionally, data from two projected climate scenarios: SSP2-4.5 [greenhouse gases emissions (GHG) will not change markedly over time and global temperature will increase by 2.0 °C by 2060] and SSP5-8.5 (marked changes in GHG emissions are expected to occur resulting in an increase of 2.4 and 4.4 °C in global temperature in the middle and at the end of the century) were included in our simulations to evaluate climate change effects on SOC dynamics in this region. Based on a 50-yr-time frame simulation, we observed that SOC stocks under ICL systems were, on average, 23% and 47% higher than in the NV (36.9 Mg ha-1) and soybean-cotton rotation under NT (30.9 Mg ha-1), respectively. Growing grasses interlaid with crops was crucial to increase SOC stocks even when disruptive soil practices were followed. Although the irrigation of grass resulted in an early increase of SOC stocks and a higher pasture stoking rate, it did not increase SOC stocks in the long term compared to non-irrigated treatments. The SSP2-4.5 and SSP5-8.5 climate scenarios had little effects on SOC dynamics in the simulated ICL systems. However, additional SOC loss (∼0.065 Mg ha-1 yr-1) is predicted to occur if the current management is not improved. These findings can help guide management decisions for the Matopiba region, Brazil, to alleviate the anthropogenic pressure associated with agriculture development. More broadly, they confirm that crop-livestock integration in croplands is a successful strategy to regenerate SOC.

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The present work demonstrates that conductive carbon paint, used for sample preparation in electron microscopy, can be a more straightforward and as-effective substitute for the metallic layer deposition usually used for the electrodeposition of metallic nanowires within porous membranes. AFM images demonstrated the good surface quality of the carbon layer. Raman spectroscopy confirmed the high crystallinity of carbon and high density of π-electrons. The electrical conductivity of the carbon layer was estimated using the linear sweep voltammetry technique. This new cathode was employed to grow continuous (Ni) and composition-modulated (Ni/Cu) nanowires within alumina templates, starting from aqueous solutions of Ni2+ and Cu2+ mixed salts. The obtention of metallic copper and nickel, and their separation can be readily observed by scanning electron microscopy and elemental mapping by EDS.

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Bacteria may be the initial cause of certain pathologies as well as a secondary agent responsible for the development of complications such as pressure ulcer infections. Pressure ulcers are a persistent health problem, especially in immunocompromised patients, and associated with infection by opportunistic microorganisms with antimicrobial resistance, such as Klebsiella pneumoniae, highlight the need for the development of new antimicrobial approaches. Thus, the aim of this study was to evaluate the antibacterial and anti-adherent activity of Origanum vulgare L. (oregano) essential oil against Klebsiella pneumoniae strains, as well as the effect of its association with synthetic antimicrobials. To this end, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) analyses were performed on microdilution plates. The assay of the Minimum Inhibitory Adherence Concentration (MIAC), with test tubes. As well as, the association study through the infusion disc method containing ampicillin (AMP), gentamicin (GEN), ciprofloxacin (CIP) and ceftriaxone (CEF). Therefore, it was possible to obtain that the essential oil of oregano presents antimicrobial and bactericidal activity, with MIC ranging between 128µg/mL and 256 µg/mL and MBC between 256 µg/mL and 512 µg/mL, on the tested K. pneumoniae strains. When used in association with ampicillin and gentamicin, oregano essential oil showed synergistic effect for some strains. Therefore, it is observed that the tested essential oil can act as a promising antibacterial in the treatment of diseases caused by K. pneumoniae.

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Bacteria may be the initial cause of certain pathologies as well as a secondary agent responsible for the development of complications such as pressure ulcer infections. Pressure ulcers are a persistent health problem, especially in immunocompromised patients, and associated with infection by opportunistic microorganisms with antimicrobial resistance, such as Klebsiella pneumoniae, highlight the need for the development of new antimicrobial approaches. Thus, the aim of this study was to evaluate the antibacterial and anti-adherent activity of Origanum vulgare L. (oregano) essential oil against Klebsiella pneumoniae strains, as well as the effect of its association with synthetic antimicrobials. To this end, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) analyses were performed on microdilution plates. The assay of the Minimum Inhibitory Adherence Concentration (MIAC), with test tubes. As well as, the association study through the infusion disc method containing ampicillin (AMP), gentamicin (GEN), ciprofloxacin (CIP) and ceftriaxone (CEF). Therefore, it was possible to obtain that the essential oil of oregano presents antimicrobial and bactericidal activity, with MIC ranging between 128µg/mL and 256 µg/mL and MBC between 256 µg/mL and 512 µg/mL, on the tested K. pneumoniae strains. When used in association with ampicillin and gentamicin, oregano essential oil showed synergistic effect for some strains. Therefore, it is observed that the tested essential oil can act as a promising antibacterial in the treatment of diseases caused by K. pneumoniae.

As bactérias podem ser a causa inicial de determinadas patologias como também um agente secundário responsável pelo desenvolvimento de complicações como as infecções das lesões por pressão. As lesões por pressão configuram um problema de saúde persistente, principalmente em pacientes imunocomprometidos, e associadas a infecção por microrganismos oportunistas com resistência antimicrobiana, como por exemplo a Klebisiella pneumoniae, ressaltam a necessidade do desenvolvimento de novas abordagens antimicrobianas. Assim, o objetivo deste estudo foi avaliar a atividade antibacteriana e antiaderente do óleo essencial de Origanum vulgare L. (orégano) contra cepas da Klebisiella pneumoniae, bem como o efeito da sua associação com antimicrobianos sintéticos. Para isso foram realizadas as análises da Concentração Mínima Inibitória (CIM) e Concentração Bactericida Mínima (CBM) em placas de micro diluição. O ensaio da Concentração Mínima de Aderência (CIMA), com tubos de ensaio. Como também, o estudo de associação através do método de disco de infusão contendo ampicilina, gentamicina, ciprofloxacino e ceftriaxona. Assim sendo, foi possível obter que o óleo essencial de orégano apresenta atividade antimicrobiana e bactericida, com CIM variando entre 128µg/mL e 256 µg/mL e CBM entre 256 µg/mL e 512 µg/mL, sobre as cepas de K. pneumoniae testadas. Quando utilizado em associação com a ampicilina e gentamicina, o óleo essencial de orégano demonstrou efeito sinérgico para algumas cepas. Portanto, observa-se que o óleo essencial testado pode atuar como um promissor antibacteriano no tratamento de doenças causadas por K. pneumoniae.

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The objective this study was to identify differences in the morphogenic patterns of four Urochloa brizantha cultivars (marandu, piatã, xaraés and paiaguás grasses) during the stockpiling period. A completely randomized design was used, with three replications, in experimental plots of 9m². The evaluations took place over 2 years. The grasses were stockpiled for 92 (Year 1) and 95 (Year 2) days. The leaf appearance rate of paiaguás grass was higher, compared to other grasses. In Year 1, the stem elongation rate of xaraés grass was higher than other grasses. At the end of stockpiling period of Year 1, the tiller population density (TPD) was higher in the paiaguás grass, intermediate in the xaraés and marandu grasses and lower in the piatã grass. At the end of the stockpiling period in Year 2, TPD was higher in the paiaguás grass canopy, intermediate in the marandu and piatã grasses canopies, and lower in the xaraés grass canopy. Paiaguás grass has greater leaf growth during the stockpiling period and is therefore suitable for use under stockpiled grazing. Xaraés grass has high stem elongation during the stockpiling period, which is why its use under stockpiled grazing must be accompanied by adjustments in pasture management.(AU)

O objetivo deste estudo foi identificar diferenças nos padrões morfogênicos de quatro cultivares de Urochloa brizantha (marandu, piatã, xaraés e paiaguás) durante o período de diferimento. Foi utilizado o delineamento inteiramente ao acaso, com três repetições, em parcelas experimentais de 9m². As avaliações ocorreram por dois anos. Os capins foram diferidos por 92 (Ano 1) e 95 (Ano 2) dias. A taxa de aparecimento foliar do capim-paiaguás foi maior, em comparação aos demais capins. No Ano 1, a taxa de alongamento do colmo do capim-xaraés foi superior aos demais capins. No final do diferimento do Ano 1, a densidade populacional de perfilho (DPP) foi maior no capim-paiaguás, intermediária nos capins xaraés e marandu e inferior no capim-piatã. No fim do período de diferimento do Ano 2, a DPP foi superior no dossel de capim-paiaguás, intermediária nos dosséis dos capins marandu e piatã, e menor no dossel de capim-xaraés. O capim-paiaguás tem maior crescimento foliar durante o período de diferimento, sendo, portanto, apropriado para uso sob pastejo diferido. O capim-xaraés apresenta elevado alongamento de colmo durante o período de diferimento, razão pela qual seu uso sob pastejo diferido deve vir acompanhado de ajustes no manejo da pastagem.(AU)

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The objective was to identify lowering strategies for Urochloa brizantha cv. Marandu in the beginning of the stockpiling period that increase forage production and improve the structure of stockpiled canopies. Three lowering strategies were evaluated: maintenance of marandu palisade grass with 15cm four months before the stockpiling period; maintenance of palisade grass with 30cm for four months, and lowering to 15cm before the stockpiling period; and maintaining of palisade grass at 45cm for four months, and lowering to 15cm before the stockpiling period. The experimental design was completely randomized, with four replications. At the end of stockpiling, the number of reproductive tillers and forage mass were higher in the canopy under 15/15cm than in the others; the percentage of live leaf was higher in the canopy under 45/15cm than under 15/15cm. Forage production during the stockpiling period was higher in the canopy under 15/15cm and lower in the under 45/15cm. Maintaining 15cm marandu palisadegrass for four months before the stockpiling period increases forage production during this period. The lowering of the marandu palisadegrass from 45 to 15cm at the beginning of the stockpiling period improves the structure of the stockpiled canopy.(AU)

Objetivou-se identificar estratégias de rebaixamento da Urochloa brizantha cv. Marandu no início do diferimento, as quais resultem em aumento da produção e em melhoria da estrutura do dossel diferido. Foram avaliadas três estratégias de rebaixamento no início do diferimento: manutenção do capim-marandu com 15cm por quatro meses antes do início do diferimento; manutenção do capim-marandu com 30cm por quatro mese, e rebaixamento para 15cm no início do diferimento; e manutenção do capim com 45cm por quatro meses e rebaixamento para 15cm no início do diferimento. O delineamento foi inteiramente ao acaso, com quatro repetições. No fim do diferimento, o número de perfilho reprodutivo e a massa de forragem foram superiores no dossel sob 15/15cm do que nos demais; a percentagem de folha viva foi maior no dossel sob 45/15cm do que sob 15/15cm. A produção de forragem durante o diferimento foi superior no dossel sob 15/15cm e inferior no sob 45/15cm. A manutenção do capim-marandu com 15cm por quatro meses antes do período de diferimento aumenta a produção de forragem neste período. O rebaixamento do capim-marandu de 45 para 15cm no início do diferimento melhora a estrutura do dossel diferido.(AU)

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An approximately 3-month-old crab-eating fox (Cerdocyon thous) was found by environmental authorities in the State of Paraiba, Northeastern Brazil and referred to a wildlife care center. The fox was presenting respiratory distress and it was referred to the Veterinary Hospital of the Federal University of Paraiba (UFPB) for ancillary testing. Abdominal and thoracic ultrasound and radiographies were performed. These imaging tests indicated the fox had a possible diaphragmatic hernia and ectopic kidney. The imageology results were confirmed on necropsy, which revealed a postero-lateral focal discontinuity of the dorsal aspect of the diaphragmatic muscle with protrusion of the gastrointestinal tract into the thoracic cavity. The stomach and intestinal loops were filled with gas and obliterated the visualization of the heart and lungs. Additionally, only the right kidney was found, and no vestigial left kidney was identified. Congenital diaphragmatic hernias are not commonly observed in wildlife but should be considered as a potential differential diagnosis for acute onset of respiratory distress in young carnivores.

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An approximately 3-month-old crab-eating fox (Cerdocyon thous) was found by environmental authorities in the State of Paraiba, Northeastern Brazil and referred to a wildlife care center. The fox was presenting respiratory distress and it was referred to the Veterinary Hospital of the Federal University of Paraiba (UFPB) for ancillary testing. Abdominal and thoracic ultrasound and radiographies were performed. These imaging tests indicated the fox had a possible diaphragmatic hernia and ectopic kidney. The imageology results were confirmed on necropsy, which revealed a postero-lateral focal discontinuity of the dorsal aspect of the diaphragmatic muscle with protrusion of the gastrointestinal tract into the thoracic cavity. The stomach and intestinal loops were filled with gas and obliterated the visualization of the heart and lungs. Additionally, only the right kidney was found, and no vestigial left kidney was identified. Congenital diaphragmatic hernias are not commonly observed in wildlife but should be considered as a potential differential diagnosis for acute onset of respiratory distress in young carnivores.(AU)

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The aim of this study was to develop and characterize a double layer biomembrane for dual drug delivery to be used for the treatment of wounds. The membrane was composed of chitosan, hydroxypropyl methylcellulose and lidocaine chloride (anesthetic drug) in the first layer, and of sodium alginate-polymyxin B sulphate (antibiotic) nanoparticles as the second layer. A product with excellent thickness (0.01-0.02 mm), adequate mechanical properties with respect to elasticity, stiffness, tension, and compatible pH for lesion application has been successfully obtained. The incorporation of the drugs was confirmed analysing the membrane cross-sections by scanning electron microscopy. A strong interaction between the drugs and the functional groups of respective polymers was confirmed by Fourier-Transform Infrared Spectroscopy, thermal analysis and X-ray diffraction. Microbiological assays showed a high antimicrobial activity when polymyxin B was present to act against the Staphylococcus aureus and Pseudomonas aeruginosa strains. Low cytotoxicity observed in a cell viability colorimetric assay and SEM analysis suggest biocompatibility between the developed biomembrane and the cell culture. The in vivo assay allowed visualizing the healing potential by calculating the wound retraction index and by histological analysis. Our results confirm the effectiveness of the developed innovative biomaterial for tissue repair and regeneration in an animal model.

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Lipase B from Candida antarctica (CalB) is the most widely used lipase, including in many industrial sectors, such as in biodiesel and pharmaceuticals production. CalB has been produced by heterologous expression using Pichia pastoris under PGK constitutive promoter (named LipB). Here, we have studied the structural features of commercial CalB and LipB enzymes using circular dichroism and fluorescence under different conditions. In the presence of denaturing agents CalB was more stable than LipB, in contrast, at increasing temperatures, LipB was more thermostable than CalB. Mass spectrometry data indicates that both enzymes have an insertion of amino acids related to α-factor yeast signal, however LipB enzyme showed the addition of nine residues at the N-terminal while CalB showed only four residues. Molecular modeling of LipB showed the formation of an amphipathic α-helix in N-terminal region that was not observed in CalB. This data suggests that this new α-helix possess could be involved in LipB thermostability. These results associated with new structural studies may provide information to the design of novel biocatalysts.

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