Produção de hidrogênio via eletrólise alcalina utilizando painel fotovoltaico como fonte de energia / Hydrogen production via alkaline electrolysis using photovoltaic panel as energy source

A demanda global de energia vem aumentando ao longo dos anos, como consequência, as emissões de carbono relacionadas à geração de energia também se expandem. A produção de hidrogênio pode ser um processo promissor, contribuindo para o avanço de uma rota de transição que leve a um desenvolvimento global sustentável. O consórcio de diferentes energias renováveis tem grande importância no desenvolvimento tecnológico para produção e armazenamento de energia. Produções de hidrogênio através de fontes renováveis como energia fotovoltaica e eólica podem contribuir para a mudança da matriz energética mundial. O presente trabalho combina diferentes formas de energias renováveis, e a produção de H2 se dá através da eletrólise alcalina da solução de hidróxido de potássio (KOH), usando como fonte de energia a luz solar, convertida em energia elétrica através de um painel fotovoltaico. Este estudo avaliou a vazão volumétrica de H2 em função da concentração do eletrólito (x1) e da irradiação (x2) e determinou as melhores condições para produção de hidrogênio, encontrando vazões de até 75 mL/min em irradiações de 950 W/m2. A qualidade do gás hidrogênio produzido também foi avaliada, atingindo 98,40% ± 0,13% de pureza, não sendo encontrados contaminantes como CO e CO2, o que torna viável seu uso em células combustível

Escherichia coli genome-wide promoter analysis: Identification of additional AtoC binding target elements

<p>Abstract</p> <p>Background</p> <p>Studies on bacterial signal transduction systems have revealed complex networks of functional interactions, where the response regulators play a pivotal role. The AtoSC system of <it>E. coli </it>activates the expression of <it>atoDAEB </it>operon genes, and the subsequent catabolism of short-chain fatty acids, upon acetoacetate induction. Transcriptome and phenotypic analyses suggested that <it>atoSC </it>is also involved in several other cellular activities, although we have recently reported a palindromic repeat within the <it>atoDAEB </it>promoter as the single, <it>cis</it>-regulatory binding site of the AtoC response regulator. In this work, we used a computational approach to explore the presence of yet unidentified AtoC binding sites within other parts of the <it>E. coli </it>genome.</p> <p>Results</p> <p>Through the implementation of a computational <it>de novo </it>motif detection workflow, a set of candidate motifs was generated, representing putative AtoC binding targets within the <it>E. coli </it>genome. In order to assess the biological relevance of the motifs and to select for experimental validation of those sequences related robustly with distinct cellular functions, we implemented a novel approach that applies Gene Ontology Term Analysis to the motif hits and selected those that were qualified through this procedure. The computational results were validated using Chromatin Immunoprecipitation assays to assess the <it>in vivo </it>binding of AtoC to the predicted sites. This process verified twenty-two additional AtoC binding sites, located not only within intergenic regions, but also within gene-encoding sequences.</p> <p>Conclusions</p> <p>This study, by tracing a number of putative AtoC binding sites, has indicated an AtoC-related cross-regulatory function. This highlights the significance of computational genome-wide approaches in elucidating complex patterns of bacterial cell regulation.</p

Future cities and autonomous vehicles: analysis of the barriers to full adoption

The inevitable upcoming technology of autonomous vehicles (AVs) will affect our cities and several aspects of our lives. The widespread adoption of AVs repose at crossing distinct barriers that prevent their full adoption. This paper presents a critical review of recent debates about AVs and analyse the key barriers to their full adoption. This study has employed a mixed research methodology on a selected database of recently published research works. Thus, the outcomes of this review integrate the barriers into two main categories; (1) User/Government perspectives that include (i) Users' acceptance and behaviour, (ii) Safety, and (iii) Legislation. (2) Information and Communication Technologies (ICT) which include (i) Computer software and hardware, (ii) Communication systems V2X, and (iii) accurate positioning and mapping. Furthermore, a framework of barriers and their relations to AVs system architecture has been suggested to support future research and technology development

Comparative analyses imply that the enigmatic sigma factor 54 is a central controller of the bacterial exterior

Contains fulltext : 95738.pdf (publisher's version ) (Open Access)BACKGROUND: Sigma-54 is a central regulator in many pathogenic bacteria and has been linked to a multitude of cellular processes like nitrogen assimilation and important functional traits such as motility, virulence, and biofilm formation. Until now it has remained obscure whether these phenomena and the control by Sigma-54 share an underlying theme. RESULTS: We have uncovered the commonality by performing a range of comparative genome analyses. A) The presence of Sigma-54 and its associated activators was determined for all sequenced prokaryotes. We observed a phylum-dependent distribution that is suggestive of an evolutionary relationship between Sigma-54 and lipopolysaccharide and flagellar biosynthesis. B) All Sigma-54 activators were identified and annotated. The relation with phosphotransfer-mediated signaling (TCS and PTS) and the transport and assimilation of carboxylates and nitrogen containing metabolites was substantiated. C) The function annotations, that were represented within the genomic context of all genes encoding Sigma-54, its activators and its promoters, were analyzed for intra-phylum representation and inter-phylum conservation. Promoters were localized using a straightforward scoring strategy that was formulated to identify similar motifs. We found clear highly-represented and conserved genetic associations with genes that concern the transport and biosynthesis of the metabolic intermediates of exopolysaccharides, flagella, lipids, lipopolysaccharides, lipoproteins and peptidoglycan. CONCLUSION: Our analyses directly implicate Sigma-54 as a central player in the control over the processes that involve the physical interaction of an organism with its environment like in the colonization of a host (virulence) or the formation of biofilm

The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

Produção de hidrogênio via eletrólise alcalina utilizando painel fotovoltaico como fonte de energia / Hydrogen production via alkaline electrolysis using photovoltaic panel as energy source

A demanda global de energia vem aumentando ao longo dos anos, como consequência, as emissões de carbono relacionadas à geração de energia também se expandem. A produção de hidrogênio pode ser um processo promissor, contribuindo para o avanço de uma rota de transição que leve a um desenvolvimento global sustentável. O consórcio de diferentes energias renováveis tem grande importância no desenvolvimento tecnológico para produção e armazenamento de energia. Produções de hidrogênio através de fontes renováveis como energia fotovoltaica e eólica podem contribuir para a mudança da matriz energética mundial. O presente trabalho combina diferentes formas de energias renováveis, e a produção de H2 se dá através da eletrólise alcalina da solução de hidróxido de potássio (KOH), usando como fonte de energia a luz solar, convertida em energia elétrica através de um painel fotovoltaico. Este estudo avaliou a vazão volumétrica de H2 em função da concentração do eletrólito (x1) e da irradiação (x2) e determinou as melhores condições para produção de hidrogênio, encontrando vazões de até 75 mL/min em irradiações de 950 W/m2. A qualidade do gás hidrogênio produzido também foi avaliada, atingindo 98,40% ± 0,13% de pureza, não sendo encontrados contaminantes como CO e CO2, o que torna viável seu uso em células combustível.</jats:p