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Because ceria (CeO2) is a key ingredient in the formulation of many catalysts, its catalytic roles have received a great amount of attention from experiment and theory. Its primary function is to enhance the oxidation activity of catalysts, which is largely governed by the low activation barrier for creating lattice O vacancies. Such an important characteristic of ceria has been exploited in CO oxidation, methane partial oxidation, volatile organic compound oxidation, and the water–gas shift (WGS) reaction and in the context of automotive applications. A great challenge of such heterogeneously catalyzed processes remains the unambiguous identification of active sites. In oxidation reactions, closing the catalytic cycle requires ceria reoxidation by gas-phase oxygen, which includes oxygen adsorption and activation. While the general mechanistic framework of such processes is accepted, only very recently has an atomic-level understanding of oxygen activation on ceria powders been achieved by combined experimental and theoretical studies using in situ multiwavelength Raman spectroscopy and DFT. Recent studies have revealed that the adsorption and activation of gas-phase oxygen on ceria is strongly facet-dependent and involves different superoxide/peroxide species, which can now be unambiguously assigned to ceria surface sites using the combined Raman and DFT approach. Our results demonstrate that, as a result of oxygen dissociation, vacant ceria lattice sites are healed, highlighting the close relationship of surface processes with lattice oxygen dynamics, which is also of technical relevance in the context of oxygen storage-release applications. A recent DFT interpretation of Raman spectra of polycrystalline ceria enables us to take account of all (sub)surface and bulk vibrational features observed in the experimental spectra and has revealed new findings of great relevance for a mechanistic understanding of ceria-based catalysts. These include the identification of s

The facet-dependent adsorption of CO on oxidized and reduced CeO2 single crystal surfaces is reviewed, with emphasis on the effect of CO coverage and the ability of state-of-the-art quantum-mechanical methods to provide reliable energies and an accurate description of the IR vibrational frequency of CO. Comparison with detailed, high-resolution experimental infrared reflection absorption spectroscopy data obtained for single crystal samples allows the assignment of the different CO vibrational bands observed on all three low-index ceria surfaces. Good agreement is achieved with the hybrid density functional theory approach with the HSE06 functional and with saturation coverage. It is shown that CO is very sensitive to the structure of cerium oxide surfaces and to the presence of oxygen vacancies. The combined theoretical-experimental approach offers new opportunities for a better characterization of ceria nanoparticles and for unraveling changes occurring during reactions involving CO at higher pressures. © 2023 Author(s).

Objective: To assess frequency, types, and mechanisms of comorbidities in people with epilepsy and verify their association with disease features and outcome. Methods: This cohort study was performed in 13 Italian epilepsy centers with nationwide distribution and accurate records. Eligible patients were children and adults diagnosed before December 31, 2005, and followed for a minimum of 10 years. Two pairs of raters independently reviewed patients’ records and classified each comorbidity. In case of disagreement, a third reviewer made the final decision. Comorbidities were classified according to type (organ/system) and underlying mechanism (causal, shared risk factors, chance association). Comorbidity types and mechanisms were described in the entire sample and according to epilepsy prognostic patterns (sustained remission, relapsing-remitting course, no remission). Results: Of 1006 included patients, 266 (26.4%) had at least one comorbidity. The most common were developmental/perinatal (7.5% of cases), psychiatric (6.2%), cardiovascular (5.3%), and endocrine/metabolic (3.8%). Among 408 reported comorbidities, the underlying mechanisms were, in decreasing order, chance association (42.2%), shared risk factors (31.1%), and causal (26.7%). Psychiatric diseases were present in 13.3% of patients with no remission, 5.9% of patients with relapsing-remitting course, and 4.8% of patients with sustained remission (p =.016). The corresponding numbers for endocrine/metabolic diseases were respectively, 9.6%, 3.4%, and 2.9% (p =.013); for respiratory diseases were 3.6%,.3%, and.3% (p =.001), and for urogenital diseases were 3.6%,.7%, and 1.6% (p =.048). The association of endocrine/metabolic, psychiatric, and respiratory comorbidities with epilepsy prognosis was confirmed by multivariable analysis adjusted for the main demographic and clinical variables, with patients with these comorbidities showing a lower probability of achieving remission. Signifi

Objective: To compare withdrawal of antiseizure medications (ASM) to continued treatment in newly diagnosed individuals achieving seizure freedom, and assess the risk of relapse and factors associated with relapse. Methods: This is a multicenter retrospective cohort study with long-term follow-up. Patients with newly diagnosed epilepsy were identified from the medical records of 13 Italian epilepsy centers and followed up until the most recent visit or death. Seizure-free patients discontinuing treatment were compared to patients who maintained treatment for baseline characteristics. Treatment was stopped upon clinical judgment. The probability of relapse was calculated with the Kaplan–Meier method. Demographic, clinical, and instrumental variables associated with relapse were assessed with Cox proportional hazards models. Results: One thousand and six patients aged 1 month to 72 years at diagnosis were enrolled and followed up for 17,892 person-years (median follow-up, 9.9 years). Three hundred and twenty patients (31.8%) underwent one or more treatment discontinuations. Factors associated with ASM withdrawal were younger age at remission and normal psychiatric examination. The probability of relapse after the first withdrawal was 16% at six months, 24% at 12 months, and 36%, 45%, and 53% at three, five, and ten years, respectively. The probability of remission after the first relapse was 59% at one month, 67%, 72, and 76% at three, six, and 12 months, respectively. Variables associated with relapse were age 14+ years, structural etiology, abnormal neuroimaging, ASM initiation after a single seizure, and symptomatic/cryptogenic epilepsy. Conclusions: About one half of seizure-free patients stopping ASM relapse in 10 years. However, the possibility of remission after relapse is high, particularly in children and patients with idiopathic/cryptogenic epilepsy. Treatment deprescription might be encouraged at least in these patients.

Enhanced methanol production is obtained over a non-promoted Cu-MgO-Al2O3 mixed oxide catalyst derived from a Cu-Mg-Al hydrotalcite precursor (HT) containing narrowly distributed small Cu NPs (2 nm). Conversions close to the equilibrium (∼20%) with a methanol selectivity of 67% are achieved at 230 °C, 20 bar, and a space velocity of 571 mL·gcat-1·h-1. Based on operando spectroscopic studies, the striking activity of this Cu-based catalyst is ascribed to the stabilization of Cu+ ions favored under reaction conditions due to lattice reorganization associated with the "HT-memory effect"promoted by water. Temperature-resolved infrared-mass spectrometry experiments have enabled the discernment of monodentate formate species, stabilized on Cu+ as the intermediate in methanol synthesis, in line with the results of density functional theory calculations. These monodentate formate species are much more reactive than bridge formate species, the latter ones behaving as intermediates in methane and CO formation. Moreover, poisoning of the Cu0 surface by strongly adsorbed species behaving as spectators is observed under reaction conditions. This work presents a detailed spectroscopic study highlighting the influence of the reaction pressure on the stabilization of active surface sites, and the possibility of enhancing methanol production on usually less active non-promoted nano-sized copper catalysts, provided that the proper support is selected, allowing the stabilization of doped Cu+. Thus, a methanol formation rate of 2.6 × 10-3 molMeOH·gcat-1·h-1 at 230 °C, 20 bar, and WHSV = 28 500 mL·gcat-1·h-1 is obtained on the Cu-MgO-Al2O3 HT-derived catalyst with 71% methanol selectivity, compared to 2.2 × 10-4 molMeOH·gcat-1·h-1 with 54% methanol selectivity obtained on a reference Cu/(Al2O3/MgO) catalyst not derived from a HT structure.

Objectives To describe the long-term prognosis of epilepsy and prognostic patterns in a large cohort of newly diagnosed patients and identify prognostic factors. Methods Study participants were 13 Italian epilepsy centres with accessible records dating back to 2005 or earlier, complete data on seizure outcome and treatments, precise epilepsy diagnosis, and follow-up of at least 10 years. Records were examined by trained neurology residents for demographics, seizure characteristics, neurological signs, psychiatric comorbidity, first electroencephalogram (EEG) and MRI/CT, epilepsy type and aetiology, antiepileptic drugs (AEDs), and 1-year, 2-year, 5-year and 10-year seizure remissions. Five predefined prognostic patterns were identified: early remission, late remission, relapsing-remitting course, worsening course and no remission. Prognostic factors were assessed using multinomial logistic regression models. Results 1006 children and adults were followed for 17 892 person-years (median 16 years; range 10-57). During follow-up, 923 patients (91.7%) experienced 1-year remission. 2-year, 5-year and 10-year remissions were present in 89.5%, 77.1% and 44.4% of cases. 5-year remission was associated with one to two seizures at diagnosis, generalised epilepsy, no psychiatric comorbidity, and treatment with one or two AEDs during follow-up. 10-year remission was associated with one or two AEDs. The most common prognostic pattern was relapsing-remitting (52.2%), followed by early remission (24.5%). 8.3% of cases experienced no remission. Predictors of a relapsing-remitting course were <6 seizures at diagnosis, (presumed) genetic aetiology and no psychiatric comorbidity. Conclusions Few seizures at diagnosis, generalised epilepsy and no psychiatric comorbidity predict early or late seizure freedom in epilepsy. Achieving remission at any time after the diagnosis does not exclude further relapses.

[EN] There is an ongoing search for materials which can accomplish the activation of two dangerous greenhouse gases like carbon dioxide and methane. In the area of C1 chemistry, the reaction between CO2 and CH4 to produce syngas (CO/H2), known as methane dry reforming (MDR), is attracting a lot of interest due to its green nature. On Pt(111), high temperatures must be used to activate the reactants, leading to a substantial deposition of carbon which makes this metal surface useless for the MDR process. In this study, we show that strong metal-support interactions present in Pt/CeO2(111) and Pt/CeO2 powders lead to systems which can bind CO2 and CH4 well at room temperature and are excellent and stable catalysts for the MDR process at moderate temperature (500 °C). The behavior of these systems was studied using a combination of in situ/operando methods (AP-XPS, XRD, and XAFS) which pointed to an active Pt-CeO2-x interface. In this interface, the oxide is far from being a passive spectator. It modifies the chemical properties of Pt, facilitating improved methane dissociation, and is directly involved in the adsorption and dissociation of CO2 making the MDR catalytic cycle possible. A comparison of the benefits gained by the use of an effective metal-oxide interface and those obtained by plain bimetallic bonding indicates that the former is much more important when optimizing the C1 chemistry associated with CO2 and CH4 conversion. The presence of elements with a different chemical nature at the metal-oxide interface opens the possibility for truly cooperative interactions in the activation of C-O and C-H bonds.

Effective catalysts for the direct conversion of methane to methanol and for methane's dry reforming to syngas are Holy Grails of catalysis research toward clean energy technologies. It has recently been discovered that Ni at low loadings on CeO2(111) is very active for both of these reactions. Revealing the nature of the active sites in such systems is paramount to a rational design of improved catalysts. Here, we correlate experimental measurements on the CeO2(111) surface to show that the most active sites are cationic Ni atoms in clusters at step edges, with a small size wherein they have the highest Ni chemical potential. We clarify the reasons for this observation using density functional theory calculations. Focusing on the activation barrier for C-H bond cleavage during the dissociative adsorption of CH4 as an example, we show that the size and morphology of the supported Ni nanoparticles together with strong Ni-support bonding and charge transfer at the step edge are key to the high catalytic activity. We anticipate that this knowledge will inspire the development of more efficient catalysts for these reactions.

Methane steam reforming (MSR) plays a key role in the production of syngas and hydrogen from natural gas. The increasing interest in the use of hydrogen for fuel cell applications demands development of catalysts with high activity at reduced operating temperatures. Ni-based catalysts are promising systems because of their high activity and low cost, but coke formation generally poses a severe problem. Studies of ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) indicate that CH4/H2O gas mixtures react with Ni/CeO2(111) surfaces to form OH, CHx, and CHxO at 300 K. All of these species are easy to form and desorb at temperatures below 700 K when the rate of the MSR process is accelerated. Density functional theory (DFT) modeling of the reaction over ceria-supported small Ni nanoparticles predicts relatively low activation barriers between 0.3 and 0.7 eV for complete dehydrogenation of methane to carbon and the barrierless activation of water at interfacial Ni sites. Hydroxyls resulting from water activation allow for CO formation via a COH intermediate with a barrier of about 0.9 eV, which is much lower than that through a pathway involving lattice oxygen from ceria. Neither methane nor water activation is a rate-determining step, and the OH-assisted CO formation through the COH intermediate constitutes a low-barrier pathway that prevents carbon accumulation. The interactions between Ni and the ceria support and the low metal loading are crucial for the reaction to proceed in a coke-free and efficient way. These results pave the way for further advances in the design of stable and highly active Ni-based catalysts for hydrogen production.