Microcalorimetry investigation on CNFs and metal supported CNFs for heterogeneous catalysis and electrocatalysis

Microcalorimetric methods, carried out under reaction conditions, provide insight into the interaction of adsorbates with the active surfaces, therefore, contributing to shade light on the nature of the active sites. In particular, the thermal effects during the chemisorption of a reactant over a solid under reaction condition provide information about the strength of the chemical bonds involved in the adsorption process and the transformations taking place as consequence of the adsorption process. In this work, microcalorimetry is applied to probe the active surface of CNF based materials for heterogeneously catalyzed and electro-catalyzed reaction. In comparative study on differently active materials, a critical analysis of the reactivity data can be delineated with respect to the surface processes occurring under good catalyst performance. Two systems have been studied: O2 chemisorption at reaction temperature on Pd nanoparticles/CNF based catalyst for the selective oxidation of alcohol to valuable compounds; CO2 chemisorption at reaction temperature on Fe/CNFs based electrocatalysts used for the reduction of CO2 to long chain hydrocarbon

Properties of graphene-related materials controlling the thermal conductivity of their polymer nanocomposites

Different types of graphene-related materials (GRM) are industrially available and have been exploited for thermal conductivity enhancement in polymers. These include materials with very different features, in terms of thickness, lateral size and composition, especially concerning the oxygen to carbon ratio and the possible presence of surface functionalization. Due to the variability of GRM properties, the differences in polymer nanocomposites preparation methods and the microstructures obtained, a large scatter of thermal conductivity performance is found in literature. However, detailed correlations between GRM-based nanocomposites features, including nanoplatelets thickness and size, defectiveness, composition and dispersion, with their thermal conductivity remain mostly undefined. In the present paper, the thermal conductivity of GRM-based polymer nanocomposites, prepared by melt polymerization of cyclic polybutylene terephtalate oligomers and exploiting 13 different GRM grades, was investigated. The selected GRM, covering a wide range of specific surface area, size and defectiveness, secure a sound basis for the understanding of the effect of GRM properties on the thermal conductivity of their relevant polymer nanocomposites. Indeed, the obtained thermal conductivity appeares to depend on the interplay between the above GRM feature. In particular, the combination of low GRM defectiveness and high filler percolation density was found to maximize the thermal conductivity of nanocomposites

Efficacy of adalimumab as second-line therapy in a pediatric cohort of crohn’s disease patients who failed infliximab therapy: The Italian society of pediatric gastroenterology, hepatology, and nutrition experience

Background: Adalimumab (Ada) treatment is an available option for pediatric Crohn’s disease (CD) and the published experience as rescue therapy is limited. Objectives: We investigated Ada efficacy in a retrospective, pediatric CD cohort who had failed previous infliximab treatment, with a minimum follow-up of 6 months. Methods: In this multicenter study, data on demographics, clinical activity, growth, laboratory values (CRP) and adverse events were collected from CD patients during follow-up. Clinical remission (CR) and response were defined with Pediatric CD Activity Index (PCDAI) score ≤10 and a decrease in PCDAI score of ≥12.5 from baseline, respectively. Results: A total of 44 patients were consecutively recruited (mean age 14.8 years): 34 of 44 (77%) had active disease (mean PCDAI score 24.5) at the time of Ada administration, with a mean disease duration of 3.4 (range 0.3–11.2) years. At 6, 12, and 18 months, out of the total of the enrolled population, CR rates were 55%, 78%, and 52%, respectively, with a significant decrease in PCDAI scores (P<0.01) and mean CRP values (mean CRP 5.7 and 2.4 mL/dL, respectively; P<0.01) at the end of follow-up. Steroid-free remission rates, considered as the total number of patients in CR who were not using steroids at the end of this study, were 93%, 95%, and 96% in 44 patients at 6, 12, and 18 months, respectively. No significant differences in growth parameters were detected. In univariate analysis of variables related to Ada efficacy, we found that only a disease duration >2 years was negatively correlated with final PCDAI score (P<0.01). Two serious adverse events were recorded: 1 meningitis and 1 medulloblastoma. Conclusion: Our data confirm Ada efficacy in pediatric patients as second-line biological therapy after infliximab failure. Longer-term prospective data are warranted to define general effectiveness and safety in pediatric CD patients

Restorative Justice-Informed Moral Acquaintance: Resolving the Dual Role Problem in Correctional and Forensic Practice

The issue of dual roles within forensic and correctional fields has typically been conceptualized as dissonance—experienced by practitioners— when attempting to adhere to the conflicting ethical requirements associated with client well-being and community protection. In this paper, we argue that the dual role problem should be conceptualized more broadly; to incorporate the relationship between the offender and their victim. We also propose that Restorative Justice (RJ) is able to provide a preliminary ethical framework to deal with this common ethical oversight. Furthermore, we unite the RJ framework with that of Ward’s (2013) moral acquaintance model to provide a more powerful approach—RJ informed moral acquaintance—aimed at addressing the ethical challenges faced by practitioners within forensic and correctional roles

Gene duplication, population genomics, and species-level differentiation within a tropical mountain shrub.

Gene duplication leads to paralogy, which complicates the de novo assembly of genotyping-by-sequencing (GBS) data. The issue of paralogous genes is exacerbated in plants, because they are particularly prone to gene duplication events. Paralogs are normally filtered from GBS data before undertaking population genomics or phylogenetic analyses. However, gene duplication plays an important role in the functional diversification of genes and it can also lead to the formation of postzygotic barriers. Using populations and closely related species of a tropical mountain shrub, we examine 1) the genomic differentiation produced by putative orthologs, and 2) the distribution of recent gene duplication among lineages and geography. We find high differentiation among populations from isolated mountain peaks and species-level differentiation within what is morphologically described as a single species. The inferred distribution of paralogs among populations is congruent with taxonomy and shows that GBS could be used to examine recent gene duplication as a source of genomic differentiation of nonmodel species

A Total Evidence Approach to Understanding Phylogenetic Relationships and Ecological Diversity in Selanginella subg. Tetragonostachys

• Premise of the Study: Several members of Selaginella are renowned for their ability to survive extreme drought and “resurrect” when conditions improve. Many of these belong to subgenus Tetragonostachys , a group of ~45 species primarily found in North and Central America, with substantial diversity in the Sonoran and Chihuahuan Deserts. We evaluated the monophyly and the age of subgenus Tetragonostachys and assess how drought tolerance contributed to the evolution of this clade. • Methods: Our study included most Tetragonostachys species, using plastid and nuclear sequences, fossil and herbarium records, and climate variables to describe the species diversity, phylogenetic relationships, divergence times, and climatic niche evolution in the subgenus. • Key Results: We found that subgenus Tetragonostachys forms a monophyletic group sister to Selaginella lepidophylla and may have diverged from other Selaginella because of a Gondwanan–Laurasian vicariance event ca. 240 mya. The North American radiation of Tetragonostachys appears to be much more recent and to have occurred during the Early Cretaceous–late Paleocene interval. We identifi ed two signifi cant and nested ecological niche shifts during the evolution of Tetragonostachys associated with extreme drought tolerance and a more recent shift to cold climates. Our analyses suggest that drought tolerance evolved in the warm deserts of southwest North America and may have been advantageous for colonization of cold and dry boreal climates. • Conclusions: Our investigation provides a foundation for future research addressing the genomics of ecological niche evolution and the potential role of reticulate evolution in Selaginella subgenus Tetragonostachys .The authors thank P. Korall for sharing data. S. Buerki, N. Alvarez, and B. Marazzi provided technical assistance and valuable comments on the manuscript. N.A. was funded by the Swiss National Science Foundation (grant no. PBNEP3-132747). C.L.A. was funded by the Swedish Research Council

A multi-layer extension of the stochastic heat equation

Motivated by recent developments on solvable directed polymer models, we define a 'multi-layer' extension of the stochastic heat equation involving non-intersecting Brownian motions.Comment: v4: substantially extended and revised versio

Operando spectroscopy study of the carbon dioxide electro-reduction by iron species on nitrogen-doped carbon

The carbon–carbon coupling via electrochemical reduction of carbon dioxide represents the biggest challenge for using this route as platform for chemicals synthesis. Here we show that nanostructured iron (III) oxyhydroxide on nitrogen-doped carbon enables high Faraday efficiency (97.4%) and selectivity to acetic acid (61%) at very-low potential (−0.5 V vs silver/silver chloride). Using a combination of electron microscopy, operando X-ray spectroscopy techniques and density functional theory simulations, we correlate the activity to acetic acid at this potential to the formation of nitrogen-coordinated iron (II) sites as single atoms or polyatomic species at the interface between iron oxyhydroxide and the nitrogen-doped carbon. The evolution of hydrogen is correlated to the formation of metallic iron and observed as dominant reaction path over iron oxyhydroxide on oxygen-doped carbon in the overall range of negative potential investigated, whereas over iron oxyhydroxide on nitrogen-doped carbon it becomes important only at more negative potentials

Influence of synthesis conditions on the structure of nickel nanoparticles and their reactivity in selective asymmetric hydrogenation

Unsupported and SiO2-supported Ni nanoparticles (NPs), were synthesised via hot-injection colloidal route using oleylamine (OAm) and trioctylphosphine (TOP) as reducing and protective agents, respectively. By adopting a multi-length scale structural characterization, it was found that by changing equivalents of OAM and TOP not only the size of the nanoparticles is affected but also the Ni electronic structure. The synthetized NPs were modified with (R,R)-tartaric acid (TA) and investigated in the asymmetric hydrogenation of methyl acetoacetate to chiral methyl-3-hydroxy butyrate. The comparative analysis of structure and catalytic performance for the synthetized catalysts has enabled us to identify a Ni metallic active surface, whereby the activity increases with the size of the metallic domains. Conversely, at the high conversion obtained for the unsupported NPs no impact of particle size on the selectivity was observed. (R)-selectivity was very high only on catalysts containing positively charged Ni species such as over the SiO2-supported Ni oxide NPs. This work shows that the chiral modification of metallic Ni NPs with TA is insufficient to maintain high selectivity towards the (R)-enantiomer at long reaction time and provide guidance for the engineering of long-term stable enantioselective catalysts