Search for: All records

Gut microbiomes can affect host health, fitness, and evolution. A large majority of gut microbiome research focuses on inferring microbial taxonomic diversity with the 16S rRNA gene, while shotgun metagenomic approaches can quantify both taxonomic and functional diversity of microbes. This level of detail is critical for understanding relationships between taxonomic, functional, and strain-level diversity of the microbial community and its interactions with host ecology, life history, and behavior. During 2023-2024, we collected fecal samples and behavioral data from a group of habituated Kinda baboons (Papio kindae) in Kasanka National Park, Zambia. We characterized taxonomic and functional microbiome diversity in more than 90 fecal samples using a shotgun metagenomics approach with the Watchmaker DNA Library Prep Kit and the HUMAnN3 bioinformatics pipeline. We found that Firmicutes was the most abundantly representative phylum, comprising more than 75% of our dataset, followed by Proteobacteria, Bacteroidota, and Candidatus Melainabacteria, each comprising less than 5% in all of our samples. Multidimensional scaling analysis of Bray-Curtis dissimilarity indices did not reveal any differences between the gut microbiome community of adult male and female baboons. These results may be due to a limited sample size but could also indicate that the relatively close social connections between males and females may facilitate the transmission of microbes among individuals and reduce sex differences. Future research will discuss these possibilities, and test hypotheses related to individual personality traits and social network characteristics. 

A<sc>bstract</sc> A search for Higgs boson (H) production at high transverse momentum (p_T) in the WW decay channel is presented. The analysis uses proton-proton collisions at$$ \sqrt{s}=13 $$ $\sqrt{s}=13$ TeV recorded by the CMS experiment in 2016–2018, corresponding to an integrated luminosity of 138 fb⁻¹. The visible decay products of the Higgs boson are reconstructed as a single large-radius jet with one isolated lepton or none (1ℓand 0ℓ, respectively;ℓ= e,μ). The H-candidate jets are identified using an advanced transformer-based algorithm and are calibrated with the Lund jet plane reweighting technique. The 1ℓchannel is further split into gluon fusion, vector boson fusion, and associated production with hadronically decaying vector boson categories, while the 0ℓchannel considers all production processes inclusively. The measured cross section times the H→WW branching fraction relative to the standard model expectation is$$ \mu =-{0.19}_{-0.46}^{+0.48} $$ $\mu =-{0.19}_{-0.46}^{+0.48}$ , indicating no evidence of a signal above the background. This measurement represents the first dedicated study of highly Lorentz-boosted H→WW decays, complementing earlier searches for high-p_THiggs boson in other decay channels. 

A search for the pair production of heavy spin- $1/2$ or spin- $3/2$ resonances ( $t^{*}$ ) in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$ is presented. Data collected with the CMS detector at the CERN LHC from 2016 to 2018 corresponding to an integrated luminosity of $138{\mathrm{fb}}^{-1}$ are used. The analysis targets benchmark signal scenarios where one $t^{*}$ decays into a top quark ( $t$ ) and a photon ( $\gamma$ ), and the other into a $t$ quark and a gluon ( $g$ ), i.e., $pp\to t^{*}\overline{t^{*}}\to tt\gamma g$ . All-hadronic final states from the $t$ pair decay chain are selected using jet substructure techniques. The signal is probed as a function of the $t^{*}$ candidate mass, which is reconstructed using the photon and a top quark candidate jet. No significant deviation from the background-only hypothesis is found. Observed (expected) upper limits on the signal cross section at 95% confidence level are set, excluding masses of spin- $1/2$ $t^{*}$ particles below 930 (930) GeV and spin- $3/2$ $t^{*}$ particles below 1330 (1390) GeV. This analysis marks the first search for heavy resonances in the $t\overline{t}\gamma g$ channel. Exploiting the high-energy photon to reduce the backgrounds, this search achieves sensitivity competitive with $pp\to t^{*}\overline{t^{*}}\to t\overline{t}gg$ searches for spin- $1/2$ $t^{*}$ despite the small expected $t^{*}\to t\gamma$ branching fraction.