14 research outputs found

    Improvement of the electrochemical behaviour of Zn-electroplated steel using regenerated Cr(III) passivation baths

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    Conversion coatings based on trivalent chromium are more sensitive to the presence of zinc and iron impurities than the chromate formulations. This fact contributes to a decrease in the quality of passivation and to the generation of a significant amount of hazardous liquid waste. Recently, a new eco-innovative process based on Emulsion Pertraction Technology (EPT) is being implemented at industrial scale for selectively removing Zn and Fe from spent passivation baths in order to enhance the lifetime of the Cr (III) baths. In this study, the effect of Zn and Fe removal on the electrochemical behaviour of Zn-electroplated steel samples was evaluated by means of polarisation curves and electrochemical impedance spectroscopy measurements at open circuit potential conditions in 3.5 g/L NaCl solutions. The main objective was to assess the benefits brought by EPT using electrochemical methods. Cr (III) passivation baths regenerated using the EPT process have been compared to the bath used in a local industry as well as to fresh and spent baths. According to the results, the samples passivated in the EPT regenerated bath showed a significant improvement in their electrochemical behaviour compared to the samples passivated in the spent baths. This study concluded the suitability of EPT for regenerating Cr (III) passivation baths

    Empirical Comparison of Graph-based Recommendation Engines for an Apps Ecosystem

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    Recommendation engines (RE) are becoming highly popular, e.g., in the area of e-commerce. A RE offers new items (products or content) to users based on their profile and historical data. The most popular algorithms used in RE are based on collaborative filtering. This technique makes recommendations based on the past behavior of other users and the similarity between users and items. In this paper we have evaluated the performance of several RE based on the properties of the networks formed by users and items. The RE use in a novel way graph theoretic concepts like edges weights or network flow. The evaluation has been conducted in a real environment (ecosystem) for recommending apps to smartphone users. The analysis of the results allows concluding that the effectiveness of a RE can be improved if the age of the data, and if a global view of the data is considered. It also shows that graph-based RE are effective, but more experiments are required for a more accurate characterization of their properties

    Effect of Welding on The Corrosion Behaviour of a Highly Alloyed Austenitic Stainless Steel UNS N06027 in Polluted Phosphoric Acid Media

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    [EN] The objective of this work is to study the effect of welding on the corrosion resistance of the austenitic stainless steel Alloy 59 (UNS N06027) as well as the galvanic corrosion generated by the base/weld pair estimated from the polarisation curves according to the mixed potential theory. The materials have been exposed to polluted phosphoric acid at several temperatures. The microstructure of the samples was studied by SEM and EDX analysis. The results show that the welding process shifts the corrosion potential values to more anodic potentials. The corrosion current densities and the passive current densities also increased by the effect of welding. This effect is aggravated with the increase in temperature. Open circuit potential values were located in the passive zone of the potentiodynamic curves, which means that the materials passivated spontaneously.The galvanic corrosion of the pair is not severe in the studied conditions. The ratio between the galvanic current density of the pair and the corrosion current density of the uncoupled anode is less than 5, which implies compatibility of the members in the couple.The authors acknowledge the Spanish Ministerio de Asuntos Exteriores y Cooperacion "MAEC" (PCI Mediterraneo C78196/07, D/023608/09, D/030177/10 and D/030177/10) for its financial support to the Krupp VDM Group (Germany) for the supplied alloys and to Dr. Asuncion Jaime for her translation assistance.Bakour, S.; Guenbour, A.; Bellaouchou, A.; Escrivá Cerdán, C.; Sánchez Tovar, R.; Leiva García, R.; Garcia-Anton, J. (2012). Effect of Welding on The Corrosion Behaviour of a Highly Alloyed Austenitic Stainless Steel UNS N06027 in Polluted Phosphoric Acid Media. International Journal of Electrochemical Science. 7(11):10530-10543. http://hdl.handle.net/10251/61163S105301054371

    Prediction of poor outcome in clostridioides difficile infection: A multicentre external validation of the toxin B amplification cycle

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    Producción CientíficaClassification of patients according to their risk of poor outcomes in Clostridioides difficile infection (CDI) would enable implementation of costly new treatment options in a subset of patients at higher risk of poor outcome. In a previous study, we found that low toxin B amplification cycle thresholds (Ct) were independently associated with poor outcome CDI. Our objective was to perform a multicentre external validation of a PCR-toxin B Ct as a marker of poor outcome CDI. We carried out a multicentre study (14 hospitals) in which the characteristics and outcome of patients with CDI were evaluated. A subanalysis of the results of the amplification curve of real-time PCR gene toxin B (XpertTM C. difficile) was performed. A total of 223 patients were included. The median age was 73.0 years, 50.2% were female, and the median Charlson index was 3.0. The comparison of poor outcome and non–poor outcome CDI episodes revealed, respectively, the following results: median age (years), 77.0 vs 72.0 (p = 0.009); patients from nursing homes, 24.4% vs 10.8% (p = 0.039); median leukocytes (cells/μl), 10,740.0 vs 8795.0 (p = 0.026); and median PCR-toxin B Ct, 23.3 vs 25.4 (p = 0.004). Multivariate analysis showed that a PCR-toxin B Ct cut-off <23.5 was significantly and independently associated with poor outcome CDI (p = 0.002; OR, 3.371; 95%CI, 1.565–7.264). This variable correctly classified 68.5% of patients. The use of this microbiological marker could facilitate early selection of patients who are at higher risk of poor outcome and are more likely to benefit from newer and more costly therapeutic options

    Prevalence and genetic characteristics of Staphylococcus aureus CC398 isolates from invasive infections in spanish hospitals, focusing on the livestock-independent CC398-MSSA clade

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    Background: Livestock-associated (LA)-CC398-MRSA is closely related to pigs, being unfrequently detected in human invasive infections. CC398-MSSA is emerging in human invasive infections in some countries, but genetic and epidemiological characteristics are still scarcely reported. Objectives: To determine the prevalence of Staphylococcus aureus (SA) CC398, both MRSA and MSSA, among blood cultures SA isolates recovered in Spanish hospitals located in regions with different pig-farming densities (PD) and characterize the recovered isolates. Methods: One thousand twenty-two SA isolates (761 MSSA, 261 MRSA) recovered from blood cultures during 6–12 months in 17 Spanish hospitals (2018–2019) were studied. CC398 lineage identification, detection of spa-types, and antibiotic resistance, virulence and human immune evasion cluster (IEC) genes were analyzed by PCR/sequencing. Results: Forty-four CC398-MSSA isolates (4.3% of SA; 5.8% of MSSA) and 10 CC398-MRSA isolates (1% of SA; 3.8% of MRSA) were detected. Eleven spa-types were found among the CC398-MSSA isolates with t571 and t1451 the most frequent spa-types detected (75%). Most of CC398-MSSA isolates were Immune-Evasion-Cluster (IEC)-positive (88.6%), tetracycline-susceptible (95.5%) and erythromycin/clindamycin–inducible-resistant/erm(T)-positive (75%). No statistical significance was detected when the CC398-MSSA/MSSA rate was correlated to PD (pigs/km2) (p = 0.108). On the contrary, CC398-MRSA isolates were all IEC-negative, predominately spa-t011 (70%), and the CC398-MRSA/MRSA rate was significantly associated to PD (p < 0.005). Conclusion: CC398-MSSA is an emerging clade in invasive infections in Spanish hospitals. CC398-MRSA (mostly t011) and CC398-MSSA (mostly t571 and t1451) show important differences, possibly suggesting divergent steps in host-adaptation evolutionary processes. While CC398-MRSA is livestock-associated (lacking IEC-system), CC398-MSSA seems to be mostly livestock-independent, carrying human-adaptation markers.

    Multicentre, randomised, single-blind, parallel group trial to compare the effectiveness of a Holter for Parkinson's symptoms against other clinical monitoring methods: study protocol

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    Introduction In recent years, multiple studies have aimed to develop and validate portable technological devices capable of monitoring the motor complications of Parkinson's disease patients (Parkinson's Holter). The effectiveness of these monitoring devices for improving clinical control is not known. Methods and analysis This is a single-blind, cluster-randomised controlled clinical trial. Neurologists from Spanish health centres will be randomly assigned to one of three study arms (1:1:1): (a) therapeutic adjustment using information from a Parkinson?s Holter that will be worn by their patients for 7 days, (b) therapeutic adjustment using information from a diary of motor fluctuations that will be completed by their patients for 7 days and (c) therapeutic adjustment using clinical information collected during consultation. It is expected that 162 consecutive patients will be included over a period of 6 months. The primary outcome is the efficiency of the Parkinson?s Holter compared with traditional clinical practice in terms of Off time reduction with respect to the baseline (recorded through a diary of motor fluctuations, which will be completed by all patients). As secondary outcomes, changes in variables related to other motor complications (dyskinesia and freezing of gait), quality of life, autonomy in activities of daily living, adherence to the monitoring system and number of doctor?patient contacts will be analysed. The noninferiority of the Parkinson's Holter against the diary of motor fluctuations in terms of Off time reduction will be studied as the exploratory objective. Ethics and dissemination approval for this study has been obtained from the Hospital Universitari de Bellvitge Ethics Committee. The results of this study will inform the practical utility of the objective information provided by a Parkinson's Holter and, therefore, the convenience of adopting this technology in clinical practice and in future clinical trials. We expect public dissemination of the results in 2022.Funding This work is supported by AbbVie S.L.U, the Instituto de Salud Carlos III [DTS17/00195] and the European Fund for Regional Development, 'A way to make Europe'

    Effectiveness of an intervention for improving drug prescription in primary care patients with multimorbidity and polypharmacy:Study protocol of a cluster randomized clinical trial (Multi-PAP project)

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    This study was funded by the Fondo de Investigaciones Sanitarias ISCIII (Grant Numbers PI15/00276, PI15/00572, PI15/00996), REDISSEC (Project Numbers RD12/0001/0012, RD16/0001/0005), and the European Regional Development Fund ("A way to build Europe").Background: Multimorbidity is associated with negative effects both on people's health and on healthcare systems. A key problem linked to multimorbidity is polypharmacy, which in turn is associated with increased risk of partly preventable adverse effects, including mortality. The Ariadne principles describe a model of care based on a thorough assessment of diseases, treatments (and potential interactions), clinical status, context and preferences of patients with multimorbidity, with the aim of prioritizing and sharing realistic treatment goals that guide an individualized management. The aim of this study is to evaluate the effectiveness of a complex intervention that implements the Ariadne principles in a population of young-old patients with multimorbidity and polypharmacy. The intervention seeks to improve the appropriateness of prescribing in primary care (PC), as measured by the medication appropriateness index (MAI) score at 6 and 12months, as compared with usual care. Methods/Design: Design:pragmatic cluster randomized clinical trial. Unit of randomization: family physician (FP). Unit of analysis: patient. Scope: PC health centres in three autonomous communities: Aragon, Madrid, and Andalusia (Spain). Population: patients aged 65-74years with multimorbidity (≥3 chronic diseases) and polypharmacy (≥5 drugs prescribed in ≥3months). Sample size: n=400 (200 per study arm). Intervention: complex intervention based on the implementation of the Ariadne principles with two components: (1) FP training and (2) FP-patient interview. Outcomes: MAI score, health services use, quality of life (Euroqol 5D-5L), pharmacotherapy and adherence to treatment (Morisky-Green, Haynes-Sackett), and clinical and socio-demographic variables. Statistical analysis: primary outcome is the difference in MAI score between T0 and T1 and corresponding 95% confidence interval. Adjustment for confounding factors will be performed by multilevel analysis. All analyses will be carried out in accordance with the intention-to-treat principle. Discussion: It is essential to provide evidence concerning interventions on PC patients with polypharmacy and multimorbidity, conducted in the context of routine clinical practice, and involving young-old patients with significant potential for preventing negative health outcomes. Trial registration: Clinicaltrials.gov, NCT02866799Publisher PDFPeer reviewe

    Empirical Comparison of Graph-based Recommendation Engines for an Apps Ecosystem

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    Recommendation engines (RE) are becoming highly popular, e.g., in the area of e-commerce. A RE offers new items (products or content) to users based on their profile and historical data. The most popular algorithms used in RE are based on collaborative filtering. This technique makes recommendations based on the past behavior of other users and the similarity between users and items. In this paper we have evaluated the performance of several RE based on the properties of the networks formed by users and items. The RE use in a novel way graph theoretic concepts like edges weights or network flow. The evaluation has been conducted in a real environment (ecosystem) for recommending apps to smartphone users. The analysis of the results allows concluding that the effectiveness of a RE can be improved if the age of the data, and if a global view of the data is considered. It also shows that graph-based RE are effective, but more experiments are required for a more accurate characterization of their properties

    Hydrodeoxygenation of 2-methoxyphenol over different Re active phases supported on SiO2 catalysts

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    The conversion of guaiacol, a lignin model compound, over SiO2-supported Re metal, oxide and sulfide catalysts in a batch reactor at 300 °C and 5 MPa of hydrogen pressure were studied. The oxide catalyst was prepared by wet impregnation with a loading of 2.5 atom of Re per nm2 of support. The sulfide and metal catalysts were prepared by sulfidation and reduction, respectively, of the Re oxide catalyst. The catalysts were characterized by N2 adsorption, X-ray photoelectron spectroscopy (XPS), temperature programmed reduction (TPR) and transmission electron microscopy (TEM). Catalytic activity was correlated with XPS analysis of the post-reaction catalysts. The ReOx/SiO2 catalyst was the most active and selective towards deoxygenated products, and this was attributed to increase in the concentration of metal oxide defect sites (due to in situ partial reduction of the oxide catalyst during the reaction). This result reveals the high potential of ReOx/SiO2 catalyst for bio-oil upgrading because it shows, among other things, that it is unnecessary to add undesirable sulfiding agent to maintain catalytic activity.The authors thank CONICYT-Chile for FONDECYT No. 1140528, ECOS–CONICYT No. C13E02, PFB-27, FONDEQUIP EQM 120096 grants and Red Doctoral REDOC.CTA, MINEDUC project UCO1202 at the University of Concepción. K. Leiva is indebted to CONICYT for doctoral grant.Peer Reviewe

    Effect of a mobile‐based intervention on mental health in frontline healthcare workers against COVID‐19: Protocol for a randomized controlled trial

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    To evaluate the impact of a psychoeducational, mobile health intervention based on cognitive behavioural therapy and mindfulness-based approaches on the mental health of healthcare workers at the frontline against COVID-19 in Spain. We will carry out a two-week, individually randomized, parallel group, controlled trial. Participants will be individually randomized to receive the PsyCovidApp intervention or control App intervention. The PsyCovidApp intervention will include five modules: emotional skills, lifestyle behaviour, work stress and burnout, social support, and practical tools. Healthcare workers having attended patients with COVID-19 will be randomized to receive the PsyCovidApp intervention (intervention group) or a control App intervention (control group). A total of 440 healthcare workers will be necessary to assure statistical power. Measures will be collected telephonically by a team of psychologists at baseline and immediately after the 2 weeks intervention period. Measures will include stress, depression and anxiety (DASS-21 questionnaire-primary endpoint), insomnia (ISI), burnout (MBI-HSS), post-traumatic stress disorder (DTS), and self-efficacy (GSE). The study was funded in May 2020, and was ethically approved in June 2020. Trial participants, outcome assessors and data analysts will be blinded to group allocation. Despite the increasing use of mobile health interventions to deliver mental health care, this area of research is still on its infancy. This study will help increase the scientific evidence about the effectiveness of this type of intervention on this specific population and context. Despite the lack of solid evidence about their effectiveness, mobile-based health interventions are already being widely implemented because of their low cost and high scalability. The findings from this study will help health services and organizations to make informed decisions in relation to the development and implementation of this type of interventions, allowing them pondering not only their attractive implementability features, but also empirical data about its benefits. NCT04393818 (ClinicalTrials.gov identifier). May 2020
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