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1
A meta-analytic perspective on Arcobacter spp. antibiotic resistance
Publicaçãopor Ferreira, SusanaOutros Autores: Luís, Ângelo; Oleastro, Mónica; Pereira, L.; Domingues, F.C.Origem: uBibliorumObjectives: Over the years, an increased prevalence of resistant strains of Arcobacter has been observed, which may be due to Arcobacter exposure to antibiotics used both in animal production and human medicine. A systematic review was performed with the objective of summarising the results of the rates of antimicrobial resistance of Arcobacter isolates. Methods: The systematic review was performed according to PRISMA (Preferred Reported Items for Systematic Reviews and Meta-Analysis) recommendations, followed by meta-analysis. Results: It was observed that the resistance rate ranged between 69.3-99.2% for penicillins and 30.5-97.4% for cephalosporins. The overall percentage of resistance to fluoroquinolones ranged from 4.3% to 14.0%, with the highest resistance percentage observed for levofloxacin. Resistance rates ranged between 10.7-39.8% for macrolides, 1.8-12.9% for aminoglycosides and 0.8-7.1% for tetracyclines. Conclusions: These results show that Arcobacter spp. present resistance to various antibiotics commonly used and advocate further studies of the associated resistance mechanisms. -
2
One-way random effects ANOVA with random sample sizes: An application to a Brazilian database on cancer registries
Publicaçãopor Capistrano, GilbertoOutros Autores: Nunes, Célia; Ferreira, Dário; Ferreira, Sandra S.; Mexia, João T.Origem: uBibliorumANOVA is routinely used in many situations, namely in medical research, where the sample sizes may not be previously known. This leads us to consider the samples sizes as realizations of random variables. The aim of this paper is to extend one-way random effects ANOVA to those situations and apply our results to a Brazilian database on cancer registries. -
3
Refinement of two-dimensional electrophoresis for vitreous proteome profiling using an artificial neural network
Publicaçãopor Santos, Fátima Raquel Milhano dosOutros Autores: Albuquerque, Tânia Gonçalves; Gaspar, Leonor Isabel Mesquita; Dias, Joao ML; Sousa, João Paulo Castro De; Paradela, Alberto et al.Origem: uBibliorumDespite technological advances, two-dimensional electrophoresis (2DE) of biological fluids, such as vitreous, remains a major challenge. In this study, artificial neural network was applied to optimize the recovery of vitreous proteins and its detection by 2DE analysis through the combination of several solubilizing agents (CHAPS, Genapol, DTT, IPG buffer), temperature, and total voltage. The highest protein recovery (94.9% ± 4.5) was achieved using 4% (w/v) CHAPS, 0.1% (v/v) Genapol, 20 mM DTT, and 2% (v/v) IPG buffer. Two iterations were required to achieve an optimized response (580 spots) using 4% (w/v) CHAPS, 0.2% (v/v) Genapol, 60 mM DTT, and 0.5% (v/v) IPG buffer at 35 kVh and 25 °C, representing a 2.4-fold improvement over the standard initial conditions of the experimental design. The analysis of depleted vitreous using the optimized protocol resulted in an additional 1.3-fold increment in protein detection over the optimal output, with an average of 761 spots detected in vitreous from different vitreoretinopathies. Our results clearly indicate the importance of combining the appropriate amount of solubilizing agents with a suitable control of the temperature and voltage to obtain high-quality gels. The high-throughput of this model provides an effective starting point for the optimization of 2DE protocols. This experimental design can be adapted to other types of matrices. Graphical abstract. -
4
Scheduling Operations and SMED: Complementary Ways to Improve Productivity
Publicaçãopor Santos, Fernando CharruaOutros Autores: Santos, Beatrice Paiva; Calderón-Arce, Cindy; Figueroa-Mata, Geovanni; Lima, Tânia M.Origem: uBibliorumIn most real cases the problem of scheduling operations are sequence de-pendent, that is, the setup time depends on the sequencing of tasks/batches in the ma-chine. Given the current industrial manufacturing trends and requirements such as high variability, customization and reduction of product life cycles, organizations seek to implement new methodologies to adapt and respond with more flexibly to new demands of the global markets. Thus, this work sought to analyse, inspired by a real case of the textile industry, how production scheduling can be understood as a complement to SMED in order to achieve productivity improvement. In the case under analysis we presented the problem of scheduling tasks in uniform parallel machines with sequence-dependent setup times. The main objective of this work was to minimize the total pro-duction time. To this goal, optimization heuristics were used, in this case, simulated annealing algorithm, that demonstrated how the use of heuristics can be an advantage to reduce setup times when associated with other methodologies such as SMED. -
5
K-essence model from the mechanical approach point of view: coupled scalar field and the late cosmic acceleration
Publicaçãopor Bouhmadi Lopez, MariamOutros Autores: Kumar, K. Sravan; Marto, João; Morais, João; Zhuk, AlexanderOrigem: uBibliorumIn this paper, we consider the Universe at the late stage of its evolution and deep inside the cell of uniformity. At these scales, we can consider the Universe to be filled with dust-like matter in the form of discretely distributed galaxies, a K-essence scalar field, playing the role of dark energy, and radiation as matter sources. We investigate such a Universe in the mechanical approach. This means that the peculiar velocities of the inhomogeneities (in the form of galaxies) as well as the fluctuations of the other perfect fluids are non-relativistic. Such fluids are designated as coupled because they are concentrated around the inhomogeneities. In the present paper, we investigate the conditions under which the K-essence scalar field with the most general form for its action can become coupled. We investigate at the background level three particular examples of the K-essence models: (i) the pure kinetic K-essence field, (ii) a K-essence with a constant speed of sound and (iii) the K-essence model with the Lagrangian bX+cX2−V(phi). We demonstrate that if the K-essence is coupled, all these K-essence models take the form of multicomponent perfect fluids where one of the component is the cosmological constant. Therefore, they can provide the late-time cosmic acceleration and be simultaneously compatible with the mechanical approach. -
6
Nineteenth-century ethnography in West Timor and the wider world: The case of J.G.F. Riedel
Publicaçãopor Schouten, Maria Johanna ChristinaOrigem: uBibliorumDiscussion of the political and scientific background of ethnographic writing about Timor in the second half of the nineteenth century, with a focus on the zones under Dutch colonial rule. The civil servant Johann Gerard Friedrich Riedel pursued ethnographic, geological, biological and other interests, in Timor and nearby islands as well as in other areas where he served such as northern Sulawesi and the Moluccas. His life and work as a collector of data and objects is screened against the scientific background of his time, especially the early developments of anthropology. -
7
Introduction: the role of entrepreneurial universities in society
Publicaçãopor Ferreira, JoãoOutros Autores: Fayolle, Alain; Ratten, Vanessa; Raposo, MarioOrigem: uBibliorumUniversities are increasingly becoming more entrepreneurial in their outlook and the way they integrate into society. This comes from the competitiveness pressures universities are facing in the global economy. More emphasis is being placed on the knowledge and service economies, which is impacting upon how universities are seen in communities. In the past universities were viewed more as teaching institutions, but this has changed, with research and development also being emphasized in terms of regional competitiveness. Therefore, the role of universities has adapted to be more entrepreneurial, as there are multiple stakeholder considerations.This chapter is structured as follows. First, the development of the term ‘entrepreneurial universities’ in the literature is discussed. Second, the important role universities have in society is discussed with reference to the increased integration of entrepreneurship in educational systems. Third, the growing influence of technology and knowledge transfer at universities is stated. Next, community interaction and entrepreneurial universities is discussed. The chapter then provides an overview of chapters in the book. A final section draws conclusions. -
8
Androgens enhance the glycolytic metabolism and lactate export in prostate cancer cells by modulating the expression of GLUT1, GLUT3, PFK, LDH and MCT4 genes
Publicaçãopor Vaz, CátiaOutros Autores: Marques, Ricardo; Alves, Marco G; Oliveira, P.F.; Cavaco, JE; Baptista, Cláudio et al.Origem: uBibliorumPurpose The present study aims to investigate the role of androgens in controlling the glycolytic metabolism and lactate efflux in prostate cancer (PCa) cells. [...] -
9
Cholinium-Based Good’s Buffers Ionic Liquids as Remarkable Stabilizers and Recyclable Preservation Media for Recombinant Small RNAs
Publicaçãopor Pedro, AugustoOutros Autores: Pereira, Patrícia; Quental, Maria J.; Carvalho, André P.; Santos, Sérgio M.; Queiroz, João et al.Origem: uBibliorumRNA is a biopolymer of high relevance in the biopharmaceuticals field and in fundamental and applied research; however, the preservation of the RNA stability is still a remarkable challenge. Herein, we demonstrate the enhanced potential of aqueous solutions of self-buffering cholinium-based Good's buffers ionic liquids (GB-ILs), at 20 and 50 % (w/w), as alternative preservation media of recombinant small RNAs. The thermal stability of RNA is highly enhanced by GB-ILs, with an increase of 14 °C in the biopolymer melting temperature - the highest increase observed up to date with ILs. Most GB-ILs investigated improve the stability of RNA at least up to 30-days, both at 25 °C and at 4 °C, without requiring the typical samples freezing. Molecular dynamics simulations were applied to better understand the molecular-level mechanisms responsible for the observed RNA improved stability. The number of IL cations surrounding the RNA chain is similar, yet with differences found for the IL anions, which are responsible for the overall charge of the biopolymer first solvation sphere. No cytotoxicity of the studied solutions containing RNA and ILs at 20 % (w/w) was observed onto two distinct human cell lines, reinforcing their potential to act as preservation media when foreseeing biopharmaceutical applications. Finally, RNA was successfully recovered from the ILs aqueous solutions, without changes in its structural integrity, and the ILs successfully recycled and reused. -
10
Implementation of the classical plasma–fluid model for simulation of dielectric barrier discharge (DBD) actuators in OpenFOAM
Publicaçãopor Abdollahzadehsangroudi, MohammadmahdiOutros Autores: Páscoa, J.C.; Oliveira, P.J.Origem: uBibliorumTo simulate the coupled plasma and fluid flow physics of dielectric-barrier discharge, a plasma–fluid model is utilized in conjunction with a compressible flow solver. The flow solver is responsible for determining the bulk flow kinetics of dominant neutral background species including mole fractions, gas temperature, pressure and velocity. The plasma solver determines the kinetics and energetics of the plasma species and accounts for finite rate chemistry. In order to achieve maximum reliability and best performance, we have utilized state-of-the-art numerical and theoretical approaches for the simulation of DBD plasma actuators. In this respect, to obtain a stable and accurate solution method, we tested and compared different existing numerical procedures, including operator-splitting algorithm, super-timestepping, and solution of the Poisson and transport equations in a semi-implicit manner. The implementation of the model is conducted in OpenFOAM. Four numerical test cases are considered in order to validate the solvers and to investigate the drawbacks/benefits of the solution approaches. The test problems include single DBD actuator driven by positive, negative and sinusoidal voltage waveforms, similar to the ones that could be found in literature. The accuracy of the results strongly depends to the choice of time step, grid size and discretization scheme. The results indicate that the super-time-stepping treatment improves the computational efficiency in comparison to explicit schemes. However, the semiimplicit treatment of the Poisson and transport equations showed better performance compared to the other tested approaches.
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