The catalytic ability of graphitic carbon nitride (g-C3N4)-supported composition-controlled PdCo catalysts towards H2 generation from the formic acid dehydrogenation reaction was assessed in this ...study and a noticeable composition dependence was evidenced. It was seen that the alloying effect combined with the nitrogen functionalities present on g-C3N4 assisted the formation of small and well-distributed nanoparticles. This fact, combined with the electronic promotion of Pd species via charge transfer from Co and basic features of the support, resulted in enhanced catalytic activities compared to that displayed by the counterpart Pd/g-C3N4, reaching a TOF value of 1193 h−1 for the most active catalyst among investigated (PdCo/g-C3N4 (1/0.7)). Furthermore, the present catalytic system showed high selectivity towards formic acid dehydrogenation, suppressing the generation of undesired CO via formic acid dehydration, which makes it a suitable candidate for practical application in fuel cells.
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•Small NPs achieved because of alloying effect and N-functionalities of the support.•Electronic promotion of Pd species via charge transfer from Co.•Activity of PdCo/g-C3N4 related to the size of NP, composition and electronic state.•PdCo/g-C3N4 (1/0.7) was the most active among investigated with a TOF of 1193 h−1.
There is an evident urgent need to find a renewable and clean energy vector to ensure the worldwide energy supply while minimizing environmental impacts, and hydrogen stands out as a promising ...alternative energy carrier. The social concern around its safe storage is constantly fostering the search for alternative options to conventional storage methods and, in this context, chemical hydrogen storage materials have produced abundant investigations with particular attention to the design of heterogeneous catalysts that can boost the generation of molecular hydrogen. Among the chemical hydrogen storage materials, formic acid and ammonia–borane hold tremendous promise, and some of the recent strategies considered for the preparation of high-performance carbon-supported catalysts are summarized in this review. The outstanding features of carbon materials and their versatility combined with the tunability of the metal active phase properties (e.g., morphology, composition, and electronic features) provide numerous options for the design of promising catalysts.
CheckMate 171 (NCT02409368) is an open-label, multicentre, phase 2 trial of nivolumab in previously treated advanced squamous non-small cell lung cancer (NSCLC), conducted as part of a post-approval ...commitment to the European Medicines Agency (EMA). We report outcomes from this trial.
Patients with Eastern Cooperative Oncology Group performance status (ECOG PS) 0–2 and disease progression during/after ≥1 systemic treatment (≥1 being platinum-based chemotherapy) for advanced or metastatic disease were treated with nivolumab 3 mg/kg every 2 weeks until progression or unacceptable toxicity. The primary end-point was incidence of grade 3–4 treatment-related select adverse events (AEs). Other end-points included overall survival (OS) and safety.
Of 811 patients treated, 103 had ECOG PS 2; 278 were aged ≥70 years and 125 were ≥75 years of age. Minimum follow-up was ~18 months. Safety was similar across populations; the most frequent grade 3–4 treatment-related select AEs in all treated patients were diarrhoea (1%), increased alanine aminotransferase (ALT, 1%), pneumonitis (0.7%), colitis (0.6%) and increased aspartate aminotransferase (AST, 0.5%). Median OS was similar in all treated patients and those aged ≥70 and ≥75: 10.0 months, 10.0 months and 11.2 months, respectively. Median OS was 5.2 months in patients with ECOG PS 2.
These results suggest that nivolumab is well tolerated and active in patients with advanced, relapsed squamous NSCLC, including the elderly, with OS outcomes consistent with phase 3 data. In patients with ECOG PS 2, nivolumab had similar tolerability, but outcomes were worse, as expected in this difficult-to-treat, poor prognosis population.
NCT02409368.
•This is the largest trial of nivolumab in patients with relapsed squamous NSCLC.•Broader eligibility criteria including ECOG PS 2 and elderly (≥70 and ≥ 75 years).•Nivolumab was well tolerated and OS outcomes were similar to CheckMate 017.•The clinical profile of nivolumab was similar in the elderly and overall population.•Nivolumab was well tolerated but had shorter OS in patients with ECOG PS 2 versus 0–1.
I present a clinical case of a 64-year-old male patient with hemochromatosis (homozygous C282Y) and crystal induced arthropathy showing the most common radiological features found in this metabolic ...disorder and the differences that may exist when compared to other primary degenerative processes or other inflammatory pathologies.
Immunotherapy has revolutionized the treatment of advanced non-small-cell lung cancer (NSCLC). In two phase III trials (CheckMate 017 and CheckMate 057), nivolumab showed an improvement in overall ...survival (OS) and favorable safety versus docetaxel in patients with previously treated, advanced squamous and nonsquamous NSCLC, respectively. We report 5-year pooled efficacy and safety from these trials.
Patients (N = 854; CheckMate 017/057 pooled) with advanced NSCLC, ECOG PS ≤ 1, and progression during or after first-line platinum-based chemotherapy were randomly assigned 1:1 to nivolumab (3 mg/kg once every 2 weeks) or docetaxel (75 mg/m
once every 3 weeks) until progression or unacceptable toxicity. The primary end point for both trials was OS; secondary end points included progression-free survival (PFS) and safety. Exploratory landmark analyses were investigated.
After the minimum follow-up of 64.2 and 64.5 months for CheckMate 017 and 057, respectively, 50 nivolumab-treated patients and nine docetaxel-treated patients were alive. Five-year pooled OS rates were 13.4% versus 2.6%, respectively; 5-year PFS rates were 8.0% versus 0%, respectively. Nivolumab-treated patients without disease progression at 2 and 3 years had an 82.0% and 93.0% chance of survival, respectively, and a 59.6% and 78.3% chance of remaining progression-free at 5 years, respectively. Treatment-related adverse events (TRAEs) were reported in 8 of 31 (25.8%) nivolumab-treated patients between 3-5 years of follow-up, seven of whom experienced new events; one (3.2%) TRAE was grade 3, and there were no grade 4 TRAEs.
At 5 years, nivolumab continued to demonstrate a survival benefit versus docetaxel, exhibiting a five-fold increase in OS rate, with no new safety signals. These data represent the first report of 5-year outcomes from randomized phase III trials of a programmed death-1 inhibitor in previously treated, advanced NSCLC.
Abstract In this work, highly efficient carbon‐supported Pd‐based catalysts for formic acid dehydrogenation were synthesized by a straightforward wet impregnation‐reduction method. The carbon support ...was obtained from a biomass residue (almond shell) prepared via H 3 PO 4 ‐assisted hydrothermal carbonization (HTC) and thermal activation. This carbon support was doped with nitrogen groups to study the effect on the electronic properties and catalytic performance of the catalysts. Investigating the formation of PdAg alloys with varying Pd : Ag molar ratios resulted in catalysts exhibiting enhanced catalytic activity compared to monometallic Pd counterparts. Notably, the Pd 1 Ag 0.5 /NAS catalyst displayed outstanding catalytic performance, achieving an initial TOF of 1716 h −1 (calculated in the first 3 minutes of reaction and expressed per mole of Pd) and maintaining substantial activity over 6 consecutive reaction cycles. This work elucidates the successful synthesis of effective catalysts, emphasizing the influence of nitrogen doping and PdAg alloy composition on catalytic behavior and stability.
Context.
The star cluster R136 inside the Large Magellanic Cloud hosts a rich population of massive stars, including the most massive stars known. The strong stellar winds of these very luminous ...stars impact their evolution and the surrounding environment. We currently lack detailed knowledge of the wind structure that is needed to quantify this impact.
Aims.
Our goal is to observationally constrain the stellar and wind properties of the massive stars in R136, in particular the wind-structure parameters related to wind clumping.
Methods.
We simultaneously analyse optical and ultraviolet spectroscopy of 53 O-type and three WNh-stars using the F
astwind
model atmosphere code and a genetic algorithm. The models account for optically thick clumps and effects related to porosity and velocity-porosity, as well as a non-void interclump medium.
Results.
We obtain stellar parameters, surface abundances, mass-loss rates, terminal velocities, and clumping characteristics and compare them to theoretical predictions and evolutionary models. The clumping properties include the density of the interclump medium and the velocity-porosity of the wind. For the first time, these characteristics are systematically measured for a wide range of effective temperatures and luminosities.
Conclusions.
We confirm a cluster age of 1.0–2.5 Myr and derived an initial stellar mass of ≥250
M
⊙
for the most massive star in our sample, R136a1. The winds of our sample stars are highly clumped, with an average clumping factor of
f
cl
= 29 ± 15. We find tentative trends in the wind-structure parameters as a function of the mass-loss rate, suggesting that the winds of stars with higher mass-loss rates are less clumped. We compare several theoretical predictions to the observed mass-loss rates and terminal velocities and find that none satisfactorily reproduce both quantities. The prescription of Krtička & Kubát (2018) matches the observed mass-loss rates best.
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