508 research outputs found

    Need for silence, craving for communication: the dyad digital education and soft skills in an emerging economy context

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    Business schools have been criticized for several things, such as lacking relevance, a too weak ethics orientation, dated paradigms, or commercialization. Simultaneously, there has been much positive change and accelerated dynamics toward forming future-ready companies and graduates. This book outlines how to better understand and master the digital transformation challenge. It is essential that business school deans, program directors, and faculty members embrace new opportunities to bring the UN-backed Principles of Responsible Management Education (PRME) to life successfully

    Assessment of ciprofloxacin photocatalysis by-products toxicity with Vibrio fischeri

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    The presence of pharmaceuticals in water has become a large concern due to the potential negative effects on humans and aquatic ecosystems. From these pharmaceuticals, antibiotics represent a serious problem since their overuse and misuse may lead to adverse environmental effects, in particular, toxicity to microflora and fauna and potential negative effects to humans [1]. Photocatalysis has become attractive to promote the degradation of contaminants in the aquatic environment since it allows their rapid and efficient removal from water, transforming them into by-products [2]. In order to evaluate toxicity of these by-products, several bio tests using bacteria (Vibrio fischeri) and algae (Daphnia spp.), among others, have been used [3]. In the present work a photocatalytic systems using commercial TiO2 and ZnO nanoparticles in suspension was used to degrade ciprofloxacin under UV radiation. Samples were withdraw over time in order to monitor degradation and toxicity. The luminescence of the bacteria Vibrio fischeri was used to test the toxicity of ciprofloxacin intermediate compounds, produced during the photocatalysis process. If a substance is toxic towards these bacteria, their normal luminescence decreases, as a consequence of a decreasing bacteria viability. Results (Figure 1) indicate that samples without ciprofloxacin degradation (t=0), in contact with bacteria (for 35 min), result in a higher luminescence than with completely degraded ciprofloxacin (t=15min). These results indicate that by products are responsible for low bacteria viability.FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project PEST-C/FIS/UI607/2011 and project PTDC/CTM-NAN/121038/2010

    TiO2/graphene and TiO2/graphene oxide nanocomposites for photocatalytic applications: A computer modeling and experimental study

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    Supplementary data related to this article can be found at http://dx. doi.org/10.1016/j.compositesb.2018.03.015.This work reports a computational study, focused on graphene (G) and graphene oxide (GO) interfaces with titanium dioxide (TiO2), and an experimental assay on the photocatalytic activity of TiO2/G and TiO2/GO nanocomposites in the degradation of two different pollutants: methylene blue and ciprofloxacin. Both carbon nanostructures were compared due to their different chemical structure: GO is a G derivative with oxygen functional groups which should promote a closer chemical interaction with TiO2 nanoparticles. Computational models of the fundamental properties of the composites indicated potentially improved photocatalytic activity compared to TiO2, namely lower band gaps and charge carrier segregation at the interfaces. These fundamental properties match qualitatively experimental results on methylene blue, which was more effectively degraded by TiO2/G and TiO2/GO nanocomposites than by pure TiO2 under UV light. In contrast, the same nanocomposites were found to be less efficient to degrade ciprofloxacin than pure TiO2 under visible and UV light. Therefore, this work showcases the relevance of an efficient matching between the catalyst and the molecular properties and structure of the pollutant.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project PESTC/FIS/UI607/2014 and PEST-C/QUI/UIO686/2014 and the CICECO Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT ref. UID/CTM/50011/2013). Access to computing facilities provided by the Project “Search-ON2: Revitalization of HPC infrastructure of UMinho” (NORTE-07-0162-FEDER-000086) is also acknowledged. P. M. Martins and Luciana Pereira thanks the FCT for grants SFRH/BD/98616/2013 and SFRH/BPD/110235/2015, respectively. MMF for a program Ciência 2008 fellowship. The authors thank financial support from the Basque Government Industry Department under the ELKARTEK Program. P.A.A.P. Marques thanks the grant IF/00917/2013/CP1162/ CT0016. Acknowledges also to FCT under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-010145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

    Application of microbial fuel cell technology for vinasse treatment and bioelectricity generation

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    Our study evaluated the performance of different two-chambered microbial fuel cell (MFC) prototypes, operated with variable distance between electrodes and Nafion membrane and specific inoculum concentration, applied for vinasse treatment.Instituto de Pesquisa Tecnológica do Estado de São Paulo/Programa Novos Talentos, through individual Research Grant attributed to Cristiane Angélica Ottoni.info:eu-repo/semantics/publishedVersio

    Multi-walled carbon nanotubes enhance methanogenesis from diverse organic compounds in anaerobic sludge and river sediments

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    Conductive nanomaterials affect anaerobic digestion (AD) processes usually by improving methane production. Nevertheless, their effect on anaerobic communities, and particularly on specific trophic groups such as syntrophic bacteria or methanogens, is not extensively reported. In this work, we evaluate the effect of multi-walled carbon nanotubes (MWCNT) on the activity of two different anaerobic microbial communities: an anaerobic sludge and a river sediment. Methane production by anaerobic sludge was assessed in the presence of different MWCNT concentrations, with direct methanogenic substrates (acetate, hydrogen) and with typical syntrophic substrates (ethanol, butyrate). MWCNT accelerated the initial specific methane production rate (SMPR) from all compounds, with a more pronounced effect on the assays with acetate and butyrate, i.e., 2.1 and 2.6 times, respectively. In the incubations with hydrogen and ethanol, SMPR increased 1.1 and 1.2 times. Experiments with the river sediment were performed in the presence of MWCNT and MWCNT impregnated with 2% iron (MWCNT-Fe). Cumulative methane production was 10.2 and 4.5 times higher in the assays with MWCNT-Fe and MWCNT, respectively, than in the assays without MWCNT. This shows the high potential of MWCNT toward bioenergy production, in waste/wastewater treatment or ex situ bioremediation in anaerobic digesters.This research was funded by the Portuguese Foundation for Science and Technology(FCT) under the scope of project MORE (POCI-01-0145-FEDER-016575), of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte, as well as FCT/MCTES trough national funds (PIDDAC) and Base Funding-UIDB/50020/20 of the Associate Laboratory LSRE-LCM-funded by national funds rough FCT/MCTES (PIDDAC). Research of O.S.G.P.S. was funded by FCT under the Scientific Employment Stimulus-Institutional Call EECINST/00049/2018.info:eu-repo/semantics/publishedVersio

    Quality of life as a prognostic marker in pulmonary arterial hypertension

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    Background: Improvement in quality of life together with better survival are the ultimate goals in the treatment of pulmonary arterial hypertension (PAH) patients. the objective of this study was to evaluate the health-related quality of life (HRQL) of pulmonary arterial hypertension (PAH) patients with the SF-36 generic questionnaire and to identify the prognostic implication of this assessment.Methods: Fifty-four consecutive newly diagnosed PAH patients (WHO classification group I) in a single PAH reference center were included. Patients were evaluated at baseline for clinical and hemodynamic parameters, and they subsequently received first-line therapy with either an endothelin receptor antagonist or a phosphodiesterase-5 inhibitor. After 16 weeks of specific PAH therapy, all patients were re-evaluated using a 6MWT and a SF 36 questionnaire, and then they were followed up for at least 36 months.Results: After treatment, the patients demonstrated an improved 6MWT (414 +/- 124 m vs. 440 +/- 113 m, p = 0.001). Specific PAH therapy also improved the HRQL scores.Patients with a baseline Physical Component Score (PCS) higher than 32 had a better survival rate than those who had a score under 32 (p = 0.04). Similarly, patients with a PCS of at least a 38 after the 16 week therapy period had a better survival rate when compared with those who did not achieve this value (p = 0.016). Unlike the absolute PCS values, the post-treatment PCS variability was unable to predict better survival rates (p = 0.58).Conclusions: Our findings suggest that HRQL is associated with prognosis in PAH. Furthermore, achieving pre-determined PCS scores might represent a specific goal to be reached in treatment-to-target strategies.Univ São Paulo, Sch Med, Pulm Dept, Inst Heart, BR-05403000 São Paulo, BrazilUniversidade Federal de São Paulo, Rheumatol Dept, São Paulo, BrazilUniversidade Federal de São Paulo, Rheumatol Dept, São Paulo, BrazilWeb of Scienc

    Photocatalytic activity of TiO2/graphene and TiO2/graphene oxide nanocomposites

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    Semiconductor-based heterogeneous photocatalysis has been one of the most promising processes for the treatment of contaminated water. Among the available catalysts, titanium dioxide (TiO2) presents the best photocatalytic properties, being chemically and biologically inert, stable, non-toxic, cheap and easy to produce. However, its energy bang gap lies in the ultraviolet (UV) range, which is responsible for a reduced spectral activation, since UV radiation corresponds to only 5% of the solar spectrum [1]. For this reason, one of the main purposes of the scientific community has been to improve the photocatalytic performance of TiO2, namely through an adequate doping of this material, or through the creation of nanocomposites, to enable photocatalysis occurrence by the incidence of visible light. One alternative concerns the application of nanocomposites of TiO2 with graphene and graphene oxide to photocatalytic processes [2]. In this work, nanocomposites of TiO2 with different weight concentrations of graphene and graphene oxide (namely 0.5%, 1%, 1.5% and 3%) were synthetized by a one-step hydrothermal method and characterized in terms of morphology, crystalline structure, vibrational modes and optical band gap. The photocatalytic activity of these nanocomposites was then evaluated through the degradation of methylene blue and ciprofloxacin solutions under UV and visible radiation. The results indicated that the studied nanocomposites presented higher degradation rates of the methylene blue than the pure TiO2, which increased with the content of graphene/graphene oxide. However, these composites proved to be less suitable to degrade the ciprofloxacin solution than the pure TiO2 nanoparticles.Portuguese Foundation for Science and Technology (FCT) - UID/FIS/04650/2013, PTDC/CTM-ENE/5387/2014 and SFRH/BD/98616/2013; Basque Government Industry Department under the ELKARTEK Program.info:eu-repo/semantics/publishedVersio

    Cluster headache and intracranial aneurysm

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    In the present study we describe the cases of two patients with cluster-like headache related to intracranial carotid artery aneurysm. One of these patients responded to verapamil prescription with headache resolution. In both cases the surgical clipping of the aneurysm resolved the cluster pain. These findings strongly suggest a pathophysiological link between the two conditions. The authors discuss the potential pathophysiological mechanisms underlying cluster-like headache due to intracranial carotid artery aneurysm
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