Publications by authors named "Augusto da Silva"

Considering the importance of alternative methodologies to animal experimentation, we propose an organoid-based biological model for in vitro blood vessel generation, achieved through co-culturing endothelial and vascular smooth muscle cells (VSMCs). Initially, the organoids underwent comprehensive characterization, revealing VSMCs (α-SMA + cells) at the periphery and endothelial cells (CD31 cells) at the core. Additionally, ephrin B2 and ephrin B4, genes implicated in arterial and venous formation respectively, were used to validate the obtained organoid.

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Poorly selective mixed-metal cluster synthesis and separation yield reaction solutions of inseparable intermetalloid cluster mixtures, which are often discarded. High-resolution mass spectrometry, however, can provide precise compositional data of such product mixtures. Structure assignments can be achieved by advanced computational screening and consideration of the complete structural space.

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Dogs with visceral leishmaniasis play a key role in the transmission cycle of to humans in the urban environment. There is a consensus regarding the importance of developing a vaccine to control this disease. Despite many efforts to develop a protective vaccine against CVL, the ones currently available, Leish-tec and LetiFend, have limited effectiveness.

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Surface water pollution has become relevant because growing population and intense industrial activities. Thus, to protect the environment from contamination, recently the electroanalytical sensors that require small sample volume and easy preparation have shown a prominent performance for pharmaceuticals monitoring. For this purpose, a miniaturized electrochemical platform was developed based on recycling obsolete computer integrated circuits (microchips), fitting with the ideals of green chemistry and circular economy.

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Adapting cross-culturally the Hospital Ethical Climate Survey to Brazilian nurses. A methodological study comprising translation, back translation, multidisciplinary committee, expert panel, pilot test and validation of the instrument. The validation was carried out with 269 nurses of a university hospital in the South of Brazil.

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Article Synopsis
  • * Vaccination presents a safer, environmentally-friendly alternative, with vaccines like TickGARD® and Gavac® showing varying success in different regions.
  • * Research is ongoing to identify and test more effective antigens for tick vaccines, aiming to improve efficacy and potentially provide cross-reactivity against other tick species and diseases.
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Reaction of the Cu(I) sources, [Cu](Mes) and [(Dipp)CuOBu] (Mes = mesityl; Dipp = 1,3-bis(2,6-diisopropylphenyl)-1-imidazol-2-ylidene) with the Zn(I) complex [Zn](Cp*) leads to a mixture of intermetallic Cu/Zn clusters with a distribution of species that is dependent on the stoichiometric ratio of the reactants, the reaction time, as well as the temperature. Systematic and careful investigation of the product mixtures rendered the isolation of two new clusters possible, , the Zn-rich, red cluster , [CuZn](Cp*) = [Cu(ZnZnCp*)(ZnCp*)], as well as the Cu-rich, dark-green cluster [CuZn](Mes)(Cp*). Structure and bonding of these two species was rationalized with the help of density functional theory calculations.

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Bone tissue-derive biomaterials have become of great interest to treat diseases of the skeletal system. Biological scaffolds of demineralized and decellularized extracellular matrices (ECM) have been developed and one of these options are ECM hydrogels derived from bovine bone. Nanomaterials may be able to regulate stem cell differentiation due to their unique physical-chemical properties.

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Two new ionic imprinted hybrid polymers (IIHP) and their corresponding non imprinted hybrid polymers (NIHP) were synthesized. The prepared IIHP was highly selective to Cd. To prepare the IIHP, 1-vinylimidazole (VIN) was used as the functional monomer, (3-mercaptopropyl) trimethoxysilane (MP) or (3-aminopropyl) trimethoxysilane (AMP) was used as the functional organosilane, trimethylolpropane (TRIM) was used as the crosslinking agent, AIBN was used as a radical initiator and TEOS was used as a functional precursor.

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Industry is constantly seeking ways to avoid corrective maintenance so as to reduce costs. Performing regular scheduled maintenance can help to mitigate this problem, but not necessarily in the most efficient way. In the context of condition-based maintenance, the main contributions of this work were to propose a methodology to treat and transform the collected data from a vibration system that simulated a motor and to build a dataset to train and test an Artificial Neural Network capable of predicting the future condition of the equipment, pointing out when a failure can happen.

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An improved atomistic understanding of the W-based two-dimensional transition-metal dichalcogenides (2D TMDs) is crucial for technological applications of 2D materials, since the presence of tungsten endows these materials with distinctive properties. However, our atomistic knowledge on the evolution of the structural, electronic, and energetic properties and on the nanoflake stability of such materials is not properly addressed hitherto. Thus, we present a density functional theory (DFT) study of stoichiometric (WQ2)n nanoflakes, with Q = S, Se, Te, and n = 1,…,16, 36, 66, and 105.

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Article Synopsis
  • The paramagnetic cluster [Cu Al ](Cp*) is formed from [CuMes] and [AlCp*], featuring an all-hydrocarbon ligand-stabilized structure.
  • This cluster has a Mackay-type nested icosahedral shape and a unique 67-electron superatom configuration with three unpaired electrons in weakly antibonding states.
  • The presence of twelve Cp* ligands protects the structure from reactivity, allowing for temperature-independent magnetism due to the formation of a conduction band.
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Neurons are specialized cells of the Central Nervous System whose function is intricately related to the neuritic network they develop to transmit information. Morphological evaluation of this network and other neuronal structures is required to establish relationships between neuronal morphology and function, and may allow monitoring physiological and pathophysiologic alterations. Fluorescence-based microphotographs are the most widely used in cellular bioimaging, but phase contrast (PhC) microphotographs are easier to obtain, more affordable, and do not require invasive, complicated and disruptive techniques.

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The properties of the free nitroxyl molecule and the nitroxyl ligand in Ru(ii) tetraammines (trans-[Ru(NH3)4(nitroxyl)(n)(L)](2+n) (n = nitroxyl charge; L = NH3, py, P(OEt)3, H2O, Cl(-) and Br(-))) were studied using density functional theory. According to the calculated conformational energies, HNO complexes are more stable than their deprotonated analogues, and the singlet configuration (trans-(1)[Ru(NH3)4(L)HNO](2+)) is lower in energy than the corresponding triplet (trans-(3)[Ru(NH3)4(L)HNO](2+)). An evaluation of the σ and π components of the L-Ru-HNO bond suggest that the increased stability of these orbitals and the enhanced contributions from the HNO orbitals correlate to shorter Ru-N(H)O distances and higher νRu-HNO stretching frequencies.

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The thermodynamic and kinetic aspects of ethyl carbamate (EC) formation through the reaction between cyanate and ethanol were investigated. The rate constant values for cyanate ion decay and EC formation are (8.0 ± 0.

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Despite the resistance developed by the Mycobacterium tuberculosis (MTb) strains, isoniazid (INH) has been recognized as one of the best drug for treatment of Tuberculosis (Tb). The coordination of INH to ruthenium metal centers was investigated as a strategy to enhance the activity of this drug against the sensitive and resistant strains of MTb. The complexes trans-[Ru(NH3)4(L)(INH)](2+) (L=SO2 or NH3) were isolated and their chemical and antituberculosis properties studied.

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Few studies have explored the relationships between nation-building, disaster risk reduction and climate change adaptation. Focusing on small island developing states, this paper examines nation-building in Timor-Leste, a small island developing state that recently achieved independence. Nation-building in Timor-Leste is explored in the context of disaster risk reduction, which necessarily includes climate change adaptation.

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The reaction between trans-[Ru(II)(NO(+))(NH3)4(L)](3+), L = ImN, IsN, Nic, P(OMe)3, P(OEt)3, and P(OH)(OEt)2, and the Fe(III) species [Fe(III)(TPPS)], metmyoglobin, and hemoglobin was monitored by UV-vis, EPR, and electrochemical techniques (DPV, CV). No reaction was observed when L = ImN, IsN, Nic, and P(OH)(OEt)2. However, when L = P(OMe)3 and P(OEt)3, the reaction was quantitative and the products were trans-[Ru(III)(H2O)(NH3)4(P(OR)3)](3+) and [Fe(II)(NO(+))] species.

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In spite of the acknowledged importance of growth-promoting bacteria, only a reduced number of studies were conducted with these microorganisms on Theobroma cacao. The objectives of this work were to study the population densities and genetic diversity of actinomycetes associated with the rhizosphere of cacao as a first step in their application in plant growth promotion and biological control. The populations densities of actinomycetes in soil and cacao roots were similar, with mean values of 1,0 x 10(6) CFU/g and 9,6 x 10(5) CFU/g, respectively.

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