RESUMO
A novel conductive composite based on PEDOT:PSS, BSA, and Nafion for effective immobilization of acetic acid bacteria on graphite electrodes as part of biosensors and microbial fuel cells has been proposed. It is shown that individual components in the composite do not have a significant negative effect on the catalytic activity of microorganisms during prolonged contact. The values of heterogeneous electron transport constants in the presence of two types of water-soluble mediators were calculated. The use of the composite as part of a microbial biosensor resulted in an electrode operating for more than 140 days. Additional modification of carbon electrodes with nanomaterial allowed to increase the sensitivity to glucose from 1.48 to 2.81 µA × mM-1 × cm-2 without affecting the affinity of bacterial enzyme complexes to the substrate. Cells in the presented composite, as part of a microbial fuel cell based on electrodes from thermally expanded graphite, retained the ability to generate electricity for more than 120 days using glucose solution as well as vegetable extract solutions as carbon sources. The obtained data expand the understanding of the composition of possible matrices for the immobilization of Gluconobacter bacteria and may be useful in the development of biosensors and biofuel cells.
Assuntos
Grafite , Polímeros , Polímeros/química , Soroalbumina Bovina , Carbono/química , Bactérias , Glucose/químicaRESUMO
Background: Numerous taxonomic studies have focused on the dung beetle genus Helictopleurus d'Orbigny, 1915, endemic to Madagascar. However, this genus stilll needs a thorough revision. Semantic technologies, such as nanopublications, hold the potential to enhance taxonomy by transforming how data are published and analysed. This paper evaluates the effectiveness of nanopublications in establishing synonyms within the genus Helictopleurus. New information: In this study, we identify four new synonyms within Helictopleurus: H.rudicollis (Fairmaire, 1898) = H.hypocrita Balthasar, 1941 syn. nov.; H.vadoni Lebis, 1960 = H.perpunctatus Balthasar, 1963 syn. nov.; H.halffteri Balthasar, 1964 = H.dorbignyi Montreuil, 2005 syn. nov.; H.clouei (Harold, 1869) = H.gibbicollis (Fairmaire, 1895) syn. nov. Helictopleurus may have a significantly larger number of synonyms than currently known, indicating potentially inaccurate estimates about its recent extinction.We also publish the newly-established synonyms as nanopublications, which are machine-readable data snippets accessible online. Additionally, we explore the utility of nanopublications in taxonomy and demonstrate their practical use with an example query for data extraction.
RESUMO
Background: Taxonomy has long struggled with analysing vast amounts of phenotypic data due to computational and accessibility challenges. Ontology-based technologies provide a framework for modelling semantic phenotypes that are understandable by computers and compliant with FAIR principles. In this paper, we explore the use of Phenoscript, an emerging language designed for creating semantic phenotypes, to produce computable species descriptions. Our case study centers on the application of this approach to dung beetles (Coleoptera, Scarabaeinae). New information: We illustrate the effectiveness of Phenoscript for creating semantic phenotypes. We also demonstrate the ability of the Phenospy python package to automatically translate Phenoscript descriptions into natural language (NL), which eliminates the need for writing traditional NL descriptions. We introduce a computational pipeline that streamlines the generation of semantic descriptions and their conversion to NL. To demonstrate the power of the semantic approach, we apply simple semantic queries to the generated phenotypic descriptions. This paper addresses the current challenges in crafting semantic species descriptions and outlines the path towards future improvements. Furthermore, we discuss the promising integration of semantic phenotypes and nanopublications, as emerging methods for sharing scientific information. Overall, our study highlights the pivotal role of ontology-based technologies in modernising taxonomy and aligning it with the evolving landscape of big data analysis and FAIR principles.
RESUMO
Microbial biofilms present one of the most widespread forms of life on Earth. The formation of microbial communities on various surfaces presents a major challenge in a variety of fields, including medicine, the food industry, shipping, etc. At the same time, this process can also be used for the benefit of humans-in bioremediation, wastewater treatment, and various biotechnological processes. The main direction of using electroactive microbial biofilms is their incorporation into the composition of biosensor and biofuel cells This review examines the fundamental knowledge acquired about the structure and formation of biofilms, the properties they have when used in bioelectrochemical devices, and the characteristics of the formation of these structures on different surfaces. Special attention is given to the potential of applying the latest advances in genetic engineering in order to improve the performance of microbial biofilm-based devices and to regulate the processes that take place within them. Finally, we highlight possible ways of dealing with the drawbacks of using biofilms in the creation of highly efficient biosensors and biofuel cells.
Assuntos
Fontes de Energia Bioelétrica , Biofilmes , Técnicas BiossensoriaisRESUMO
Defect-free thin-walled samples were built using wire arc additive manufacturing (WAAM) combined with the "coldArc" deposition technique by feeding a Ti-6Al-4V welding wire and using two deposition strategies, namely with and without the welding torch weaving. The microstructures formed in these samples were examined in relation to mechanical characteristics. The arc torch weaving at 1 Hz allowed us to interfere with the epitaxial growth of the ß-Ti columnar grains and, thus, obtain them a lower aspect ratio. Upon cooling, the α/α'+ß structure was formed inside the former ß-Ti grains, and this structure proved to be more uniform as compared to that of the samples built without the weaving. The subtransus quenching of the samples in water did not have any effect on the structure and properties of samples built with the arc torch weaving, whereas a more uniform grain structure was formed in the sample built without weaving. Quenching resulted also in a reduction in the relative elongation by 30% in both cases.