Probing the crossover in CO desorption from single crystal to nanoparticulate Ru model catalysts

cited By 10International audienceUsing model catalysts, we demonstrate that CO desorption from Ru surfaces can be switched from that typical of single crystal surfaces to one more characteristic of supported nanoparticles. First, the CO desorption behaviour from Ru nanoparticles supported on highly oriented pyrolytic graphite was studied. Both mass-selected and thermally evaporated nanoparticles were deposited. TPD spectra from the mass-selected nanoparticles exhibit a desorption peak located around 410 K with a broad shoulder extending from around 480 K to 600 K, while spectra obtained from thermally evaporated nanoparticles exhibit a single broad feature from ∼350 K to ∼450 K. A room temperature deposited 50 Å thick Ru film displays a characteristic nanoparticle-like spectrum with a broad desorption feature at ∼420 K and a shoulder extending from ∼450 K to ∼600 K. Subsequent annealing of this film at 900 K produced a polycrystalline morphology of flat Ru(001) terraces separated by monatomic steps. The CO desorption spectrum from this surface resembles that obtained on single crystal Ru(001) with two large desorption features located at 390 K and 450 K due to molecular desorption from terrace sites, and a much smaller peak at ∼530 K due to desorption of dissociatively adsorbed CO at step sites. In a second experiment, ion sputtering was used to create surface defects on a Ru(0 1 54) single crystal surface. A gradual shift away from the desorption spectrum typical of a Ru(001) surface towards one resembling desorption from supported Ru nanoparticles was observed with increasing sputter time. © 2011 the Owner Societies

Levels of SARS-CoV-2 antibodies among fully vaccinated individuals with Delta or Omicron variant breakthrough infections

SARS-CoV-2 variants of concern have continuously evolved and may erode vaccine induced immunity. In this observational cohort study, we determine the risk of breakthrough infection in a fully vaccinated cohort. SARS-CoV-2 anti-spike IgG levels were measured before first SARS-CoV-2 vaccination and at day 21–28, 90 and 180, as well as after booster vaccination. Breakthrough infections were captured through the Danish National Microbiology database. incidence rate ratio (IRR) for breakthrough infection at time-updated anti-spike IgG levels was determined using Poisson regression. Among 6076 participants, 127 and 364 breakthrough infections due to Delta and Omicron variants were observed. IRR was 0.29 (95% CI 0.15–0.56) for breakthrough infection with the Delta variant, comparing the highest and lowest quintiles of anti-spike IgG. For Omicron, no significant differences in IRR were observed. These results suggest that quantitative level of anti-spike IgG have limited impact on the risk of breakthrough infection with Omicron

Characteristics Associated with Serological Covid-19 Vaccine Response and Durability in an Older Population with Significant Comorbidity:The Danish Nationwide ENFORCE Study

OBJECTIVES: To identify individual characteristics associated with serological COVID-19 vaccine responsiveness and durability of vaccine-induced antibodies. METHODS: Adults without history of SARS-CoV-2 infection from the Danish population scheduled for SARS-CoV-2 vaccination were enrolled in this parallel group, phase IV study. SARS-CoV-2 Spike IgG and Spike-ACE2-receptor-blocking antibodies were measured at days 0, 21, 90 and 180. Vaccine responsiveness was categorized according to Spike IgG and Spike-ACE2-receptor-blocking levels at day 90 post-1(st) vaccination. Non-durable vaccine-response was defined as day 90 responders that no longer had significant responses by day 180. RESULTS: Of 6544 participants completing two vaccine doses (median age 64, interquartile range:54–75), 3654 (55.8%) received BTN162b2, 2472 (37.8%) mRNA-1273, and 418 (6.4%) ChAdOx1 followed by a mRNA vaccine. Levels of both types of antibodies increased from baseline to day 90 and then decreased to day 180. The decrease was more pronounced for levels of Spike-ACE2-receptor-blocking antibodies than for Spike IgG. Proportions with vaccine hypo-responsiveness and lack of durable response were 5.0% and 12.1% for Spike IgG; 12.7% and 39.6% for Spike-ACE2-receptor-blocking antibody levels, respectively. Male sex, vaccine type and number of co-morbidities were associated with all four outcomes. Additionally, age >=75y was associated with hypo-responsiveness for Spike-ACE2-receptor-blocking antibodies (adjusted odds-ratio:1.59, 95% confidence interval:1.25–2.01) but not for Spike IgG. CONCLUSIONS: Comorbidity, male sex and vaccine type were risk factors for hypo-responsiveness and non-durable response to COVID-19 vaccination. The functional activity of vaccine-induced antibodies declined with increasing age and had waned to pre-2(nd) vaccination levels for most individuals after 6 months

MiDAS 4: A global catalogue of full-length 16S rRNA gene sequences and taxonomy for studies of bacterial communities in wastewater treatment plants

Microbial communities are responsible for biological wastewater treatment, but our knowledge of their diversity and function is still poor. Here, we sequence more than 5 million high-quality, full-length 16S rRNA gene sequences from 740 wastewater treatment plants (WWTPs) across the world and use the sequences to construct the ‘MiDAS 4’ database. MiDAS 4 is an amplicon sequence variant resolved, full-length 16S rRNA gene reference database with a comprehensive taxonomy from domain to species level for all sequences. We use an independent dataset (269 WWTPs) to show that MiDAS 4, compared to commonly used universal reference databases, provides a better coverage for WWTP bacteria and an improved rate of genus and species level classification. Taking advantage of MiDAS 4, we carry out an amplicon-based, global-scale microbial community profiling of activated sludge plants using two common sets of primers targeting regions of the 16S rRNA gene, revealing how environmental conditions and biogeography shape the activated sludge microbiota. We also identify core and conditionally rare or abundant taxa, encompassing 966 genera and 1530 species that represent approximately 80% and 50% of the accumulated read abundance, respectively. Finally, we show that for well-studied functional guilds, such as nitrifiers or polyphosphate-accumulating organisms, the same genera are prevalent worldwide, with only a few abundant species in each genus.Fil: Dueholm, Morten Kam Dahl. Aalborg University; DinamarcaFil: Nierychlo, Marta. Aalborg University; DinamarcaFil: Andersen, Kasper Skytte. Aalborg University; DinamarcaFil: Rudkjøbing, Vibeke. Aalborg University; DinamarcaFil: Knutsson, Simon. Aalborg University; DinamarcaFil: Arriaga, Sonia. Instituto Potosino de Investigación Científica y Tecnológica; MéxicoFil: Bakke, Rune. University College of Southeast Norway; NoruegaFil: Boon, Nico. University of Ghent; BélgicaFil: Bux, Faizal. Durban University of Technology; SudáfricaFil: Christensson, Magnus. Veolia Water Technologies Ab; SueciaFil: Chua, Adeline Seak May. University Malaya; MalasiaFil: Curtis, Thomas P.. University of Newcastle; Reino UnidoFil: Cytryn, Eddie. Agricultural Research Organization Of Israel; IsraelFil: Erijman, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina. Universidad de Buenos Aires; ArgentinaFil: Etchebehere, Claudia. Instituto de Investigaciones Biológicas "Clemente Estable"; UruguayFil: Fatta Kassinos, Despo. University of Cyprus; ChipreFil: Frigon, Dominic. McGill University; CanadáFil: Garcia Chaves, Maria Carolina. Universidad de Antioquia; ColombiaFil: Gu, April Z.. Cornell University; Estados UnidosFil: Horn, Harald. Karlsruher Institut Für Technologie; AlemaniaFil: Jenkins, David. David Jenkins & Associates Inc; Estados UnidosFil: Kreuzinger, Norbert. Tu Wien; AustriaFil: Kumari, Sheena. Durban University of Technology; SudáfricaFil: Lanham, Ana. University of Bath; Reino UnidoFil: Law, Yingyu. Singapore Centre For Environmental Life Sciences Engineering; SingapurFil: Leiknes, TorOve. King Abdullah University of Science and Technology; Arabia SauditaFil: Morgenroth, Eberhard. Eth Zürich; SuizaFil: Muszyński, Adam. Politechnika Warszawska; PoloniaFil: Petrovski, Steve. La Trobe University; AustraliaFil: Pijuan, Maite. Catalan Institute For Water Research; EspañaFil: Pillai, Suraj Babu. Va Tech Wabag Ltd; IndiaFil: Reis, Maria A. M.. Universidade Nova de Lisboa; PortugalFil: Rong, Qi. Chinese Academy of Sciences; ChinaFil: Rossetti, Simona. Istituto Di Ricerca Sulle Acque (irsa) ; Consiglio Nazionale Delle Ricerche;Fil: Seviour, Robert. La Trobe University; AustraliaFil: Tooker, Nick. University of Massachussets; Estados UnidosFil: Vainio, Pirjo. Espoo R&D Center; FinlandiaFil: van Loosdrecht, Mark. Delft University of Technology; Países BajosFil: Vikraman, R.. VA Tech Wabag, Philippines Inc; FilipinasFil: Wanner, Jiří. University of Chemistry And Technology; República ChecaFil: Weissbrodt, David. Delft University of Technology; Países BajosFil: Wen, Xianghua. Tsinghua University; ChinaFil: Zhang, Tong. The University of Hong Kong; Hong KongFil: Nielsen, Per H.. Aalborg University; DinamarcaFil: Albertsen, Mads. Aalborg University; DinamarcaFil: Nielsen, Per Halkjær. Aalborg University; Dinamarc

Greenland Geothermal Heat Flow Database and Map (Version 1)

We compile and analyze all available geothermal heat flow measurements collected in and around Greenland into a new database of 419 sites and generate an accompanying spatial map. This database includes 290 sites previously reported by the International Heat Flow Commission (IHFC), for which we now standardize measurement and metadata quality. This database also includes 129 new sites, which have not been previously reported by the IHFC. These new sites consist of 88 offshore measurements and 41 onshore measurements, of which 24 are subglacial. We employ machine learning to synthesize these in situ measurements into a gridded geothermal heat flow model that is consistent across both continental and marine areas in and around Greenland. This model has a native horizontal resolution of 55ĝ€¯km. In comparison to five existing Greenland geothermal heat flow models, our model has the lowest mean geothermal heat flow for Greenland onshore areas. Our modeled heat flow in central North Greenland is highly sensitive to whether the NGRIP (North GReenland Ice core Project) elevated heat flow anomaly is included in the training dataset. Our model's most distinctive spatial feature is pronounced low geothermal heat flow (<ĝ€¯40ĝ€¯mWĝ€¯m-2) across the North Atlantic Craton of southern Greenland. Crucially, our model does not show an area of elevated heat flow that might be interpreted as remnant from the Icelandic plume track. Finally, we discuss the substantial influence of paleoclimatic and other corrections on geothermal heat flow measurements in Greenland. The in situ measurement database and gridded heat flow model, as well as other supporting materials, are freely available from the GEUS Dataverse (10.22008/FK2/F9P03L; Colgan and Wansing, 2021).publishedVersionPeer reviewe