353 research outputs found

    Effect of lanthanum on the catalytic properties of PtSn/γ-Al2O3 bimetallic catalysts prepared by successive impregnation and controlled surface reaction.

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    Bimetallic PtSn/γ -Al2O3–La2O3 catalysts were prepared by two comparative methods, successive impregnation (SI) and controlled surface reaction (CSR). FTIR-pyridine adsorption revealed a decrease in support acidity as a function of lanthanum content. Oxidized Pt2+ was identified by CO-FTIR chemisorption and by XPS spectra on catalysts prepared by SI. When the CSR preparation method was used, reduced Pt0 was observed and oxidized Pt2+ was not detected. As the lanthanum content increased a diminution in cyclohexane dehydrogenation and n-heptane conversion was observed. Low hydrogenolysis and high selectivity to C7-olefins were obtained in both preparations. It is proposed that lanthanum in SI catalysts stabilizes the platinum in an oxidation state, Pt2+, and diminishes the support acidity. In CSR preparations the lanthanum effect is limited to inhibit the support acidity and hence to the bifunctional reactions occurring during the n-heptane conversion

    Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

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    Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

    Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

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    There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity

    Abstracts from the Food Allergy and Anaphylaxis Meeting 2016

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    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    ANÁLISIS Y PROPUESTAS DE POLÍTICAS ENERGÉTICAS PARA EL DESARROLLO DEL MERCADO DE GAS NATURAL EN MÉXICO

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    En 1995, el Ejecutivo Federal emprendió una profunda reforma en la industria del gas natural dirigida a promover la inversión productiva y el desarrollo eficiente del mercado nacional. El contexto en que nacieron esas iniciativas fue el potencial atractivo que el país poseía del recurso natural, el interés por diversificar y usar combustibles menos contaminantes, los precios bajos de las referencias en los noventas, darle un valor agregado a un subproducto de la extracción de petróleo y aprovechar las ventajas de la tecnología de ciclo combinado en el sector eléctrico. El proceso de liberalización de la cadena de valor de esta industria en México estuvo vinculado directamente con la globalización económica, y generó cambios a nivel estructural. Esto permitió promover la inversión complementaria del sector privado en el transporte, distribución y almacenamiento de gas natural, además de que Pemex se enfocara a sus actividades sustantivas de producción y procesamiento de hidrocarburos. Al analizar las políticas energéticas que originaron y han dado curso al desarrollo del mercado de gas natural en el país, se observa que han perdido inercia en los últimos años. Por lo que, se realizó un diagnóstico del mercado de gas natural basado en la guía para la formulación de políticas energéticas “Energía y desarrollo Sustentable en América Latina y el Caribe” de la CEPAL/OLADE/GTZ, mismo que permitió detectar cambios en el entorno y generar algunas propuestas para dar un nuevo impulso al desarrollo de este mercado. Si bien se detectaron fortalezas en el funcionamiento de las políticas energéticas tras la reforma, existen áreas de oportunidad que podrán ser objeto de estudio hacia un mejor funcionamiento del mercado. Sin duda, el objetivo del diagnóstico es presentar las interacciones del mercado de gas natural con su política energética, además del vínculo que hay con la economía, la sociedad y el medio ambiente. En las áreas de oportunidad de la política energética nacional dirigida al mercado de gas natural, se encuentran: mejorar el aprovechamiento en el sistema de abastecimiento del gas natural, lo cual dará sustentabilidad al desarrollo en largo plazo; mientras que en el corto plazo la reactivación del crecimiento del mercado estará en función del desarrollo de infraestructura, mejoras en el funcionamiento del mercado de gas natural y en superar prácticas anticompetitivas, así como la reducción de subsidios que influyan en la dinámica del consumo. En casi todos los casos, se exigen un vínculo más arraigado con el “desarrollo sustentable”. Superar estas barreras podrá darle un nuevo impulso al desarrollo del mercado promoviendo la seguridad de abastecimiento, eficiencia en el uso del recurso natural, cuidado al medio ambiente, desarrollo de infraestructura y mayor acceso a la población

    Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

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    Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)

    Search for a resonance decaying to a W boson and a photon in proton-proton collisions at s= \sqrt{s} = 13 TeV using leptonic W boson decays

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    A search for a new charged particle X with mass between 0.3 and 2.0 TeV decaying to a W boson and a photon is presented, using proton-proton collision data at a center-of-mass energy of 13 TeV, collected by the CMS experiment and corresponding to an integrated luminosity of 138 fb1 ^{-1} . Particle X has electric charge ± \pm 1 and is assumed to have spin 0. The search is performed using the electron and muon decays of the W boson. No significant excess above the predicted background is observed. The upper limit at 95% confidence level on the product of the production cross section of the X and its branching fraction to a W boson and a photon is found to be 94 (137) fb for a 0.3 TeV resonance and 0.75 (0.81) fb for a 2.0 TeV resonance, for an X width-to-mass ratio of 0.01% (5%). This search presents the most stringent constraints to date on the existence of such resonances across the probed mass range. A statistical combination with an earlier study based on the hadronic decay mode of the W boson is also performed, and the upper limit at 95% confidence level for a 2.0 TeV resonance is reduced to 0.50 (0.63) fb for an X width-to-mass ratio of 0.01% (5%).A search for a new charged particle X with mass between 0.3 and 2.0 TeV decaying to a W boson and a photon is presented, using proton-proton collision data at a center-of-mass energy of 13 TeV, collected by the CMS experiment and corresponding to an integrated luminosity of 138 fb1^{-1}. Particle X has electric charge ±\pm1 and is assumed to have spin 0. The search is performed using the electron and muon decays of the W boson. No significant excess above the predicted background is observed. The upper limit at 95% confidence level on the product of the production cross section of the X and its branching fraction to a W boson and a photon is found to be 94 (137) fb for a 0.3 TeV resonance and 0.75 (0.81) fb for a 2.0 TeV resonance, for an X width-to-mass ratio of 0.01% (5%). This search presents the most stringent constraints to date on the existence of such resonances across the probed mass range. A statistical combination with an earlier study based on the hadronic decay mode of the W boson is also performed, and the upper limit at 95% confidence level for a 2.0 TeV resonance is reduced to 0.50 (0.63) fb for an X width-to-mass ratio of 0.01% (5%)

    Measurement of inclusive and differential cross sections for W+^{+}W^{-} production in proton-proton collisions at s= \sqrt{s} = 13.6 TeV

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    Measurements at s= \sqrt{s}= 13.6 TeV of the opposite-sign W boson pair production cross section in proton-proton collisions are presented. The data used in this study were collected with the CMS detector at the CERN LHC in 2022, and correspond to an integrated luminosity of 34.8 fb1 ^{-1} . Events are selected by requiring one electron and one muon of opposite charge. A maximum likelihood fit is performed on signal- and background-enriched data categories defined by the flavour and charge of the leptons, the number of jets, and number of jets originating from b quarks. An inclusive W+^{+}W^{-} production cross section of 125.7 ± \pm 5.6 pb is measured, in agreement with standard model predictions. Cross sections are also reported in a fiducial region close to that of the detector acceptance, both inclusively and differentially, as a function of the jet multiplicity in the event. For first time in proton-proton collisions, WW events with at least two reconstructed jets are studied and compared with recent theoretical predictions.Measurements at s\sqrt{s} = 13.6 TeV of the opposite-sign W boson pair production cross section in proton-proton collisions are presented. The data used in this study were collected with the CMS detector at the CERN LHC in 2022, and correspond to an integrated luminosity of 34.8 fb1^{-1}. Events are selected by requiring one electron and one muon of opposite charge. A maximum likelihood fit is performed on signal- and background-enriched data categories defined by the flavour and charge of the leptons, the number of jets, and number of jets originating from b quarks. An inclusive W+^+W^- production cross section of 125.7 ±\pm 5.6 pb is measured, in agreement with standard model predictions. Cross sections are also reported in a fiducial region close to that of the detector acceptance, both inclusively and differentially, as a function of the jet multiplicity in the event. For first time in proton-proton collisions, WW events with at least two reconstructed jets are studied and compared with recent theoretical predictions

    Search for CPCP violation in D0^0\to KS0^0_\mathrm{S}KS0^0_\mathrm{S} decays in proton-proton collisions at s\sqrt{s} = 13 TeV

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    International audienceA search is reported for charge-parity D0^0\to KS0^0_\mathrm{S}KS0^0_\mathrm{S}CPCP violation in D0^0\to KS0^0_\mathrm{S}KS0^0_\mathrm{S} decays, using data collected in proton-proton collisions at s\sqrt{s} = 13 TeV recorded by the CMS experiment in 2018. The analysis uses a dedicated data set that corresponds to an integrated luminosity of 41.6 fb1^{-1}, which consists of about 10 billion events containing a pair of ẖadrons, nearly all of which decay to charm hadrons. The flavor of the neutral D meson is determined by the pion charge in the reconstructed decays D+^{*+}\to D0π+^0\pi^+ and D^{*-}\to D0π^0\pi^-. The D0^0\to KS0^0_\mathrm{S}KS0^0_\mathrm{S}CPCP asymmetry in D0^0\to KS0^0_\mathrm{S}KS0^0_\mathrm{S} is measured to be ACPA_{CP}( KS0^0_\mathrm{S}KS0^0_\mathrm{S}) = (6.2 ±\pm 3.0 ±\pm 0.2 ±\pm 0.8)%, where the three uncertainties represent the statistical uncertainty, the systematic uncertainty, and the uncertainty in the measurement of the D0^0 \to KS0^0_\mathrm{S}KS0^0_\mathrm{S} CPCP asymmetry in the D0^0 \to KS0π+π^0_\mathrm{S}\pi^+\pi^- decay. This is the first D0^0 \to KS0^0_\mathrm{S}KS0^0_\mathrm{S} CPCP asymmetry measurement by CMS in the charm sector as well as the first to utilize a fully hadronic final state
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