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The functionalization of silica supports with isonicotinamide (NIC) facilitated the stabilization of small (3.5 nm), spherical cobalt nanoparticles (CoNPs) used in catalytic hydrogenation. Various silica matrices, including amorphous, mesoporous, and non‐porous ones, were synthesized and post‐grafted with NIC to serve as ligands for stabilizing CoNPs. Comprehensive characterization techniques were employed to fully analyze the prepared materials, which were then utilized in the catalytic hydrogenation of acetophenone, serving as a benchmark reaction to assess the impact of different silica supports on catalysis. The porosity and surface nature of the silica matrices played crucial roles in anchoring the amide ligand, and the presence of the ligand was essential for stabilizing the nanoparticles. Among the catalysts tested, CoNPs@SBA‐15/NIC exhibited the highest catalytic activity and demonstrated excellent performance in the hydrogenation of alkenes, nitriles, ketones, and quinoline under relatively mild conditions. No significant alteration in catalyst morphology or leaching of metal was observed after the reaction. Notably, this catalytic system achieved turnover numbers comparable to those of homogeneous cobalt catalysts. Additionally, one‐pot tandem reductive amination reactions starting from aldehydes and involving both amines and nitrobenzene yielded secondary and tertiary amines in good yields, highlighting the robustness and versatility of the catalyst. [ABSTRACT FROM AUTHOR]

As condições de degradação em que se encontram algumas áreas verdes da cidade recaem, diretamente, sobre a queda de sua qualidade e a perda de suas funções, além de poderem oferecer riscos a seus usuários. Nesse sentido, o objetivo é verificar quais os fatores de riscos, potenciais, que as áreas verdes públicas de Natal/RN oferecem para a população local, em virtude das incontingências advindas das condições de degradação e inadequações presentes. Foram realizadas leituras sobre a temática em pauta, seguida de levantamentos de dados secundários sobre as características e condições de 168 áreas verdes públicas da cidade, selecionadas a partir de uma amostragem aleatória simples, estratificada por bairro. Os resultados apontam que diante das condições das suas estruturas de lazer, dos equipamentos urbanos de suporte, das condições de limpeza, da arborização e da permeabilidade do solo nas áreas verdes analisadas, essas, apresentam fatores de riscos potenciais, como, acidentes físicos, poluição do ar, do solo e visual; alagamentos, atos de violência, aumento de temperatura e desconforto térmico, para os seus usuários, para a população do entorno e para a cidade como um todo, em virtude da abrangência do problema em questão.

Abstract Purpose To evaluate the efficacy of portal vein embolization (PVE) with n-Butyl-cyanoacrylate (NBCA) through an ipsilateral approach before major hepatectomy. Secondary end-points were PVE safety, liver resection and patient outcome. Methods Over a 5-year period 50 non-cirrhotic consecutive patients were included with primary or secondary liver cancer treatable by hepatectomy with a liver remnant (FLR) volume less than 25% or less than 40% in diseased livers. Results There were 37 men and 13 women with a mean age of 57 years. Colorectal liver metastases were the most frequent tumor and patients were previously exposed to chemotherapy. FLR increased from 422 ml to 629 ml (P

In this work, we studied the optical properties of Dy-doped Gd2O3 nanoparticles (NPs) before and after their APTES functionalisation. We obtained luminescent Dy@Gd2O3 NPs (0.5, 1, and 5% mol) using a modified polyol method. Our work describes their detailed structural analysis using FT-IR, XRD, HRTEM, TGA and XAS techniques. The results show that these systems present a crystalline structure with a body-centred cubic cell and particle sizes of 10 nm. The dopant position was inferred as substitutional, through XAS analysis at the M4,5-edges of Gd and Dy and K-edge of O, and in C2 sites, based on photoluminescence studies. There was sensitization of the luminescence by the matrix as shown by the emission increase of the hypersensitive transition (6F9/2 → 6H13/2, 572 nm) and also a broadband appears around 510 nm attributed to defects in Gd2O3. An enhanced emissive lifetime of 398 μs was found for the sample doped at 1%. We functionalised the Dy@Gd2O3 (at 1%) NPs with 3-aminopropiltrietoxisilane (APTES) for further application as a biomarker sensor. We found that these NPs conserved their luminescence after adding the surface agent (avoiding quenching effects) making them potential materials for biosensing. [ABSTRACT FROM AUTHOR]

The combination of first‐row transition compounds or nanoparticles with silica‐based supports offers a great possibility for catalyst design. In particular, iron, cobalt and nickel‐based materials rise in attention due to their availability, low cost and interesting reactivity, enabling transformations that are not possible with noble metals. Different support strategies exist where mesoporous silica‐based supports are of particular interest due to their morphology and stability. Their high surface area, tunable pore size and volume and both, thermal and chemical stability, are of great interest in terms of catalyst adsorption and reactants diffusion. The state of the art on the catalyzed transformations to attain fine chemicals is nowadays explored from a sustainable point of view. However, up to now, it is difficult to predict or understand the key features in silica supported first‐row transition metals‐based catalyst, despite the fact that there are widely applied. The rational tailoring of nanosized materials immobilized on silica‐based supports and their application in catalysis requires to be reviewed. [ABSTRACT FROM AUTHOR]

Amine and nicotinamide groups grafted on ordered mesoporous silica (OMS) were investigated as stabilizers for RhNPs used as catalysts in the hydrogenation of several substrates, including carbonyl and aryl groups. Supported RhNPs on functionalized OMS were prepared by controlled decomposition of an organometallic precursor of rhodium under dihydrogen pressure. The resulting materials were characterized thoroughly by spectroscopic and physical techniques (FTIR, TGA, BET, SEM, TEM, EDX, XPS) to confirm the formation of spherical rhodium nanoparticles with a narrow size distribution supported on the silica surface. The use of nicotinamide functionalized OMS as a support afforded small RhNPs (2.3 ± 0.3 nm), and their size and shape were maintained after the catalyzed acetophenone hydrogenation. In contrast, amine-functionalized OMS formed RhNP aggregates after the catalytic reaction. The supported RhNPs could selectively reduce alkenyl, carbonyl, aryl and heteroaryl groups and were active in the reductive amination of phenol and morpholine, using a low concentration of the precious metal (0.07–0.18 mol%). [ABSTRACT FROM AUTHOR]

Abstract: Tricarbonyl-η5-pentadienylmanganese reacts with mercaptans RSH, R=Ph, C6F5, m-NH2C6H4, p-NH2C6H4, and HSCH2CH2 in the presence of ECH2CH2E, E=–PPh2 or –NH2 to give novel stable terminal thiolate mononuclear complexes fac-Mn(CO)3(SR)(Ph2PCH2CH2PPh2-κ2-P,P′) for R=Ph, C6F5, m-NH2C6H4, p-NH2C6H4, and HSCH2CH2 and fac-Mn(CO)3(SR)(H2NCH2CH2NH2-κ2-N,N′) for R=Ph and C6F5. Upon reaction of tricarbonyl-η5-pentadienylmanganese with ethylenediamine a dinuclear complex [fac-Mn(CO)3(μ-H2NCH2CH2NH-κ2-N,N′)]2 was formed wherein the diaminyl ligand functions in the capacity of chelating and bridging ligand. [ABSTRACT FROM AUTHOR]

The use of supported rhodium nanoparticles (RhNPs) is gaining attention due to the drive for better catalyst performance and sustainability. Silica-based supports are promising for RhNP immobilization because of their thermal and chemical stability. Functionalizing silica allows for the design of catalysts with improved activity for biomass transformations. In this study, we synthesized rhodium nanoparticles (RhNPs) supported on N-functionalized silica-based materials, utilizing SBA-15 as the support and functionalizing it with either nicotinamide or an imidazolium-based ionic liquid. Solid-state 29 Si and 13 C NMR experiments confirmed successful ligand anchoring onto the silica surface. RhNPs@SBA-15-Imz[NTf 2 ] and RhNPs@SBA-15-NIC were efficiently prepared and extensively characterized, revealing small, spherical, and well-dispersed fcc Rh nanoparticles on the support surface, confirmed by XPS analyses detecting metallic rhodium, Rh(I), and Rh(III) species. The catalytic performance of these materials is assessed in the hydrogenation of biomass-derived substrates, including furfural, levulinic acid, terpenes, vanillin, and eugenol, among others, underscoring their potential in sustainable chemical transformations. The nanocatalysts demonstrated excellent recyclability and resistance to metal leaching over multiple cycles. The study shows that neutral and ionic silica grafting fragments differently stabilize RhNPs, affecting their morphology, size, and interaction with silanol groups, which impacts their catalytic activity.

In this work, we studied the optical properties of Dy-doped Gd 2 O 3 nanoparticles (NPs) before and after their APTES functionalisation. We obtained luminescent Dy@Gd 2 O 3 NPs (0.5, 1, and 5% mol) using a modified polyol method. Our work describes their detailed structural analysis using FT-IR, XRD, HRTEM, TGA and XAS techniques. The results show that these systems present a crystalline structure with a body-centred cubic cell and particle sizes of 10 nm. The dopant position was inferred as substitutional, through XAS analysis at the M 4,5 -edges of Gd and Dy and K-edge of O, and in C 2 sites, based on photoluminescence studies. There was sensitization of the luminescence by the matrix as shown by the emission increase of the hypersensitive transition ( 6 F 9/2 → 6 H 13/2 , 572 nm) and also a broadband appears around 510 nm attributed to defects in Gd 2 O 3 . An enhanced emissive lifetime of 398 μs was found for the sample doped at 1%. We functionalised the Dy@Gd 2 O 3 (at 1%) NPs with 3-aminopropiltrietoxisilane (APTES) for further application as a biomarker sensor. We found that these NPs conserved their luminescence after adding the surface agent (avoiding quenching effects) making them potential materials for biosensing.

The Database of Intrinsically Disordered Proteins (DisProt, URL: https://disprot.org) is the major repository of manually curated annotations of intrinsically disordered proteins and regions from the literature. We report here recent updates of DisProt version 9, including a restyled web interface, refactored Intrinsically Disordered Proteins Ontology (IDPO), improvements in the curation process and significant content growth of around 30%. Higher quality and consistency of annotations is provided by a newly implemented reviewing process and training of curators. The increased curation capacity is fostered by the integration of DisProt with APICURON, a dedicated resource for the proper attribution and recognition of biocuration efforts. Better interoperability is provided through the adoption of the Minimum Information About Disorder (MIADE) standard, an active collaboration with the Gene Ontology (GO) and Evidence and Conclusion Ontology (ECO) consortia and the support of the ELIXIR infrastructure., (© The Author(s) 2021. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Amine and nicotinamide groups grafted on ordered mesoporous silica (OMS) were investigated as stabilizers for RhNPs used as catalysts in the hydrogenation of several substrates, including carbonyl and aryl groups. Supported RhNPs on functionalized OMS were prepared by controlled decomposition of an organometallic precursor of rhodium under dihydrogen pressure. The resulting materials were characterized thoroughly by spectroscopic and physical techniques (FTIR, TGA, BET, SEM, TEM, EDX, XPS) to confirm the formation of spherical rhodium nanoparticles with a narrow size distribution supported on the silica surface. The use of nicotinamide functionalized OMS as a support afforded small RhNPs (2.3 ± 0.3 nm), and their size and shape were maintained after the catalyzed acetophenone hydrogenation. In contrast, amine-functionalized OMS formed RhNP aggregates after the catalytic reaction. The supported RhNPs could selectively reduce alkenyl, carbonyl, aryl and heteroaryl groups and were active in the reductive amination of phenol and morpholine, using a low concentration of the precious metal (0.07-0.18 mol%).