8 research outputs found

    Crotonaldehyde hydrogenation on Rh/TiO2 catalysts. In situ DRIFTS studies

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    The surface and catalytic properties in the vapor-phase hydrogenation of crotonaldehyde on Rh/TiO2 has been studied. It was found that a partial reduction of the support produces a surface decoration of the metal component. Thus, interfacial sites are created, which are responsible of an increase in the selectivity to crotyl alcohol, via enhancement of the polarization of the C=O bond. Photoelectron spectra revelead that rhodium is in different oxidation states, with a contribution of ca. 20 % Rhd + and 80 % RhÂș species for LTR catalyst and only a slight increase of Rhd + for HTR catalyst. TEM studies revelead that Rh has metal particle size close 3 nm with small increases in the catalyst reduced at high temperature. DRIFTS essayed carried out under reaction conditions allowed to identify crotonaldehyde species strongly adsorbed through the C=C bond and weakly coordinated through both the C=C and C=O bonds. After reduction at 723 K an increase in the peak at 1660 cm-1 ascribed to an interaction between the carbonyl group and the surface, was observed. This peak seems to be stabilized at interfacial Rh/TiOx sites The deactivation in crotyl alcohol formation can be ascribed to the generation of strongly chemisorbed asymmetric carboxylate species detected by band at 1740 cm-1. This band grows at expense of crotonaldehyde O s - bonded intermediate chemisorbed on coordinatively unsaturated sites (Lewis acid sites) responsible of the crotyl alcohol obtaintion (detected by a band at 1653 cm-1). Additionally, a small band at 2068 cm-1 assigned to CO adsorbed on transition metals, which increases with time on-stream may explain the deactivation of the catalysts in flow systems

    RICORS2040 : The need for collaborative research in chronic kidney disease

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    Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true

    Cultural dimensions of dengue that help or hinder its prevention in Mexico [Dimensiones culturales del dengue que favorecen o dificultan su prevenciĂłn en MĂ©xico]

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    Objective: To describe the cultural dimensions that might help or hinder dengue prevention in two Mexican localities having different experiences related to this disease. Methods: A cognitive-cultural anthropological study was conducted involving the participation of 160 adults selected through purposeful sampling. The techniques of free lists and pile-sorting were used for investigating terms associated with the concept "dengue." A consensus analysis was carried out by the factoring of principal components, hierarchical cluster analysis, and multidimensional scaling. Results: Greater consensus was observed among participants from the population having more historical experience with dengue-Santiago Ixcuintla, Nayarit-as well as more structured cultural and complex dimensions than in Guadalajara. In the latter case, participants showed a more fragmented conception of dengue, with insufficient information on its symptoms, mechanisms of transmission, and vector reservoirs. Three cultural dimensions were identified as hindering dengue prevention: confusing and insufficient information, placing responsibility for prevention on other people or on public agencies, and excessive confidence in fumigation as a preventive measure. Conclusions: These obstacles will need to be taken into account in the design and implementation of future prevention campaigns, disseminating information that explains the risks of fumigation and the importance of citizens and authorities jointly participating in the search for a comprehensive and sustainable solution to the dengue problem

    Cultural dimensions of dengue that help or hinder its prevention in Mexico [Dimensiones culturales del dengue que favorecen o dificultan su prevenciĂłn en MĂ©xico]

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    Objective: To describe the cultural dimensions that might help or hinder dengue prevention in two Mexican localities having different experiences related to this disease. Methods: A cognitive-cultural anthropological study was conducted involving the participation of 160 adults selected through purposeful sampling. The techniques of free lists and pile-sorting were used for investigating terms associated with the concept "dengue." A consensus analysis was carried out by the factoring of principal components, hierarchical cluster analysis, and multidimensional scaling. Results: Greater consensus was observed among participants from the population having more historical experience with dengue-Santiago Ixcuintla, Nayarit-as well as more structured cultural and complex dimensions than in Guadalajara. In the latter case, participants showed a more fragmented conception of dengue, with insufficient information on its symptoms, mechanisms of transmission, and vector reservoirs. Three cultural dimensions were identified as hindering dengue prevention: confusing and insufficient information, placing responsibility for prevention on other people or on public agencies, and excessive confidence in fumigation as a preventive measure. Conclusions: These obstacles will need to be taken into account in the design and implementation of future prevention campaigns, disseminating information that explains the risks of fumigation and the importance of citizens and authorities jointly participating in the search for a comprehensive and sustainable solution to the dengue problem

    Correction to: Is diet partly responsible for differences in COVID-19 death rates between and within countries? (Clinical and Translational Allergy, (2020), 10, 1, (16), 10.1186/s13601-020-00323-0)

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    Following publication of the original article [1], the authors identified an error in the affiliation list. The affiliation of author G. Walter Canonica should have been split up into two affiliations: ‱ Personalized Medicine, Asthma and Allergy – Humanitas Clinical and Research Center – IRCCS, Rozzano (MI), Italy ‱ Department of Biomedical Sciences, Humanitas University, Pieve Emanuele (MI), Italy The corrected affiliation list is reflected in this Correction. © 2020, The Author(s)
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