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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 measurement of the angular structure of inclusive jets and those containing a prompt D⁰meson in proton-proton collisions at the LHC at a center-of-mass energy of 5.02 TeV is presented. The data corresponding to an integrated luminosity of 301 pb⁻¹were collected by the CMS experiment in 2017. Two jet grooming algorithms, late-k_Tand soft drop, are used to study the intrajet radiation pattern using iterative Cambridge-Aachen declustering. The splitting-angle distributions of jets with transverse momentum (p_T) of around 100 GeV, obtained with these two algorithms, show that there is a shift of the distribution for jets containing a prompt D⁰meson with respect to inclusive jets. The suppression of emissions at small angles observed in the late-k_Tgrooming approach is consistent with the dead-cone effect, whereas the similar suppression for splittings selected with the soft-drop algorithm appears to be induced by gluon splitting to charm quark-antiquark pairs at large angles. The measured distributions are corrected to the particle level and can be used to constrain model predictions for the substructure of high-p_Tcharm quark jets. 

A hot and dense state of nuclear matter, known as the quark-gluon plasma, is created in collisions of ultrarelativistic heavy nuclei. Highly energetic quarks and gluons, collectively referred to as partons, lose energy as they travel through this matter, leading to suppressed production of particles with large transverse momenta ( $p_{\mathrm{T}}$). Conversely, high- $p_{\mathrm{T}}$particle suppression has not been seen in proton-lead collisions, raising questions regarding the minimum system size required to observe parton energy loss. Oxygen-oxygen (OO) collisions examine a region of effective system size that lies between these two extreme cases. The CMS detector at the CERN LHC has been used to quantify charged-particle production in inclusive OO collisions for the first time via measurements of the nuclear modification factor ( $R_{\mathrm{AA}}$). The $R_{\mathrm{AA}}$is derived by comparing particle production to expectations based on proton-proton ( $pp$) data and has a value of unity in the absence of nuclear effects. The data for OO and $pp$collisions at a nucleon-nucleon center-of-mass energy $\sqrt{s_{\mathrm{NN}}}=5.36\mathrm{TeV}$correspond to integrated luminosities of $6.1{\mathrm{nb}}^{-1}$and $1.02{\mathrm{pb}}^{-1}$, respectively. The $R_{\mathrm{AA}}$is below unity with a minimum of $0.69\pm 0.04$around $p_{\mathrm{T}}=6\mathrm{GeV}$. The data exhibit better agreement with theoretical models incorporating parton energy loss as compared to baseline models without energy loss.