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Protecting nanoparticles with a carbon matrix can enhance the durability of the catalysts in alkaline fuel cells (AFC) and is well‐documented. While others have tried complex syntheses to produce small nanoparticle catalysts, in this work, in order to scale‐up batches of 15 g or more, carbon‐cap (or carbon‐coating) protected Vulcan XC72‐supported Pd−Ni (1–2) nanoparticles (Pd−Niacc/C) were successfully synthesized via a one‐step dry‐synthesis process. This catalyst was compared with a commercial Pd−Ni/Vulcan XC72 material (PdNi/C, Premetek) in terms of hydrogen oxidation reaction (HOR) activity and stability. To produce less ordered carbon caps (versus graphite/graphene), a low‐temperature heat‐treatment (below 500 °C) was used, resulting in Pd−Niacc/C of unique electrochemical properties: easily electrochemically activated, this catalyst outperforms PdNi/C for alkaline HOR and proves more durable under highly oxidizing accelerated stress test (AST) conditions. Identical location transmission electron microscopy (ILTEM), X‐ray photoelectron spectroscopy (XPS) and rotating disk electrode (RDE) measurements demonstrate how the Ni‐rich surface plays an important role in HOR activity for both PdNi/C and Pd‐Niacc/C and that the protective carbon‐coating of the latter ensures better durability of performance and better resistance to materials degradation. [ABSTRACT FROM AUTHOR]

Dogs are occasionally susceptible to SARS-CoV-2, developing few or no clinical signs.Epidemiological surveillance of SARS-CoV-2 in dogs requires testing to distinguish it from other canine coronaviruses. In the last year, significant advances have been made in the diagnosis of SARS-CoV-2, allowing its surveillance in both human and animal populations. Here, using ELISA and automated western blotting (AWB) assays, we performed a longitudinal study on 809 apparently healthy dogs from different regions of France to investigate anti-SARS-CoV-2 antibodies. There were three main groups: (i) 356 dogs sampled once before the pandemic, (ii) 235 dogs sampled once during the pandemic, and (iii) 218 dogs, including 82 dogs sampled twice (before and during the pandemic), 125 dogs sampled twice during the pandemic and 11 dogs sampled three times (once before and twice during the pandemic). Using ELISA, seroprevalence was significantly higher during the pandemic [5.5% (25/453)] than during the pre-pandemic period [1.1% (5/449)]. Among the 218 dogs sampled twice, at least 8 ELISA-seroconversions were observed. ELISA positive pre-pandemic sera were not confirmed in serial tests by AWB, indicating possible ELISA cross-reactivity, probably with other canine coronaviruses. A significant difference was observed between these two serological tests (Q = 88, p = 0.008). A clear correlation was observed between SARS-CoV-2 seroprevalence in dogs and the incidence of SARS-CoV-2 infection in human population from the same area. AWB could be used as a second line assay to confirm the doubtful and discrepant ELISA results in dogs. Our results confirm the previous experimental models regarding the susceptibility of dogs to SARS-CoV-2, suggesting that viral transmission from and between dogs is weak or absent. However, the new variants with multiple mutations could adapt to dogs; this hypothesis cannot be ruled out in the absence of genomic data on SARS-CoV-2 from dogs.

Every year, the world faces vector-borne diseases including arboviral (arthropod-borne viral) diseases caused by several, possibly fatal flaviviruses. The way they spread is related to a complex episystem involving several elements including vector abundance, animal carriers, and the flavivirus itself, which makes the disease difficult to manage. Here, we serologically screened 556 animals (358 dogs and 198 horses) using ELISA and a serum neutralisation test (SNT) for the anti-IgG antibodies directed against the West Nile (WNV) and Usutu (USUV) viruses. The animals investigated were split into two groups according to their exposure to the risk linked to the abundance of mosquitoes and migratory birds as well as the geographical distribution of arbovirus cases (458 animals from areas exposed to risk and 98 not exposed to risk). Overall, 25/310 dogs (8.1%) and 2/148 horses (1.3%) tested positive for SNT WNV and/or USUV in geographically exposed areas. Animals in unexposed areas were all negative. The geographical distribution of WNV seroprevalence in dogs was the same as the distribution of reported autochthonous human cases. Interestingly, a non-negligible seroprevalence caused by an as yet unidentified flavivirus other than WNV, USUV, or tick-borne encephalitis virus (TBEV) was detected in 18.6% (28/150) and 3.7% (4/106) of the investigated dogs and horses from the Hérault department, in the southeast of France, respectively. These data highlight the role of outdoor dogs as suitable sentinels for the evidence of WNV and USUV circulation in each area. In addition, the serological detection of an as yet unidentified flavivirus circulating in the Hérault department deserves greater attention, as this may constitute a serious threat to public and animal health. [ABSTRACT FROM AUTHOR]