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Honey bees contribute substantially to the world economy through pollination services and honey production. In the U.S. alone, honey bee pollination is estimated to contribute at least $11 billion annually, primarily through the pollination of specialty crops. However, beekeepers lose about half of their hives every season due to disease, insecticides, and other environmental factors. Here, we explore and validate a spatiotemporal statistical model ofVarroa destructormite burden (in mites/300 bees) in managed honey bee colonies, exploring the impact of both environmental factors and beekeeper behaviors. We examine risk factors forVarroainfestation using apiary inspection data collected across the state of Illinois over 2018–2019, and we test the models using inspection data from 2020–2021. After accounting for spatial and temporal trends, we find that most environmental factors (e.g., floral quality, insecticide load) are not predictive ofVarroaintensity, while lower numbers of nearby apiaries and several beekeeper behaviors (e.g., supplemental feeding and mite monitoring/treatment) are protective againstVarroa. Interestingly, while monitoringandtreating forVarroais protective, treatingwithoutmonitoring is no more effective than not treating at all. This is an important result supporting Integrated Pest Management (IPM) approaches. 

Abstract Henrietta Swan Leavitt’s discovery of the relationship between the period and luminosity (hereafter the Leavitt Law) of 25 variable stars in the Small Magellanic Cloud, published in 1912, revolutionized cosmology. These variables, eventually identified as Cepheids, became the first known “standard candles” for measuring extragalactic distances and remain the gold standard for this task today. Leavitt measured light curves, periods, and minimum and maximum magnitudes from painstaking visual inspection of photographic plates. Her work paved the way for the first precise series of distance measurements that helped set the scale of the Universe, and later the discovery of its expansion by Edwin Hubble in 1929. Here, we re-analyze Leavitt’s first Period–Luminosity relation using observations of the same set of stars but with modern data and methods of Cepheid analysis. Using only data from Leavitt’s notebooks, we assess the quality of her light curves, measured periods, and the slope and scatter of her Period–Luminosity relations. We show that modern data and methods, for the same objects, reduce the scatter of the Period–Luminosity relation by a factor of two. We also find a bias brightward at the short period end, due to the nonlinearity of the plates and environmental crowding. Overall, Leavitt’s results are in excellent agreement with contemporary measurements, reinforcing the value of Cepheids in cosmology today, a testament to the enduring quality of her work. 

Corpse-mediated pathogen transmission is a viable route through which naïve hosts can become infected, but its likelihood for honey bee-associated viruses is largely unknown. While these viruses can be easily detected in deceased bees, it remains unclear if they stay infectious within postmortem hosts or if enough viral RNA degradation-and subsequently virus inactivation-occurs post-host death to render these viruses inviable. This knowledge gap has important implications for how researchers perform honey bee virus studies and for our general understanding of honey bee virus transmission. To better understand the resiliency of honey bee-associated viruses within deceased hosts, we first tested the hypothesis that postmortem specimens, stored in colony-normal temperature and humidity conditions, can be reliably used to quantify virus abundance. To determine this, we experimentally-infected adult honey bees with Israeli acute paralysis virus (IAPV) and then measured the virus levels of individuals sampled live or at different postmortem time points (4, 12, 24, and 48 hours post-death) using RT-qPCR and a standard curve absolute quantification method. We found no significant differences based on when bees were sampled, indicating that postmortem honey bees are statistically comparable to using live-sampled bees and can be reliably used to quantify absolute IAPV abundance. We then performed a follow-up experiment that determined whether or not the IAPV detected in postmortem bees remained infectious over time. We found that IAPV extracted from postmortem bees remained highly infectious for at least 48 hours post-death, indicating that any viral RNA degradation that may have occurred during the postmortem interval did not adversely affect IAPV's overall infectivity. The results from this study suggest that IAPV is more resilient to degradation than previously assumed, support the use of postmortem bees for downstream IAPV analyses, and indicate that postmortem hosts can act as sources of IAPV infection for susceptible individuals. 

Abstract Mobile genetic elements (MGEs), such as plasmids and bacteriophages, are major contributors to the ecology and evolution of host-associated microbes due to a continuum of symbiotic interactions and by mediating gene flow via horizontal gene transmission. However, while myriad studies have investigated relationships between MGEs and variation in fitness among microbial and eukaryotic hosts, few studies have incorporated this variation into the context of MGE evolution and ecology. Combining HiC-resolved metagenomics with the model honey bee worker gut microbiome, we show that the worker gut contains a dense, nested MGE community that exhibits a wide degree of host range variation among microbial hosts. Using measures of gene similarity and syntenty, we show that plasmids likely mediate gene flow between individual honey bee colonies, though these plasmids exhibit broad host range variation within their individual microbiomes. We further show that phage-microbe networks exhibit high variation among individual metagenomes, and that phages show broad host range with respect to both the number and phylogenetic distance of their hosts. Finally, we provide evidence that measures of nucleotide variation positively correlate with host range in bee-associated phages, and that functional targets of diversifying selection are partitioning differently between broad or narrow host range phages. Our work underscores the variability of MGE x microbial interactions within host-associated microbial communities and highlights the genomic variation associated with MGE host range diversity. 

Abstract Despite the queen’s crucial reproductive role in honey bee colonies, queen diet and feeding behavior remain remarkably enigmatic, with most studies assuming they are solely fed nutritious glandular secretions (i.e., royal jelly) by workers. This colors our understanding of basic honey bee biology and how governmental agencies assess pesticide risk. We hypothesized that adult queens also consume honey and pollen. Through experiments with queenright laboratory microcolonies fed with marked diets, we demonstrate that queens are fed pollen and nectar by workers and can also feed directly. We then measured pollen content in mature, unmanipulated queens sacrificed from 43 conventional field colonies from two distinct geographical regions. Similar to workers, we found pollen in almost all queens guts, though at expectedly lower quantities than in young workers. These findings suggest queens have a more complex, dynamic diet than previously thought, raising new questions about how dietary habits and feeding behaviors influence pesticide risk and other aspects of queen biology. 

Abstract The discovery of pulsations in ultramassive (UM) white dwarfs (WDs) can help to probe their interiors and unveil their core composition and crystallized mass fraction through asteroseismic techniques. To date, the richest pulsating UM WD known is BPM 37093 with 8 modes detected, for which detailed asteroseismic analysis has been performed in the past. In this work, we report the discovery of 19 pulsation modes in the UM WD star WD J0135+5722, making it the richest pulsating hydrogen-atmosphere UM WD known to date. This object exhibits multiperiodic luminosity variations with periods ranging from 137 to 1345 s, typical of pulsating WDs in the ZZ Ceti instability strip, which is centered atT_eff ∼ 12,000 K. We estimate the stellar mass of WD J0135+5722 by different methods, resulting inM_⋆ ∼ 1.12–1.14M_⊙if the star’s core is made of oxygen and neon orM_⋆ ∼ 1.14–1.15M_⊙if the star hosts a carbon oxygen core. Future analysis of the star periods could shed light on the core chemical composition through asteroseismology. 

Abstract At the low-redshift end (z< 0.05) of the Hubble diagram with Type Ia Supernovae (SNe Ia), the contribution to Hubble residual scatter from peculiar velocities (PVs) is of similar size to that due to the limitations of the standardization of the SN Ia light curves. A way to improve the redshift measurement of the SN host galaxy is to utilize the average redshift of the galaxy group, effectively averaging over small-scale/intracluster PVs. One limiting factor is the fraction of SN host galaxies in galaxy groups, previously found to be 30% using (relatively incomplete) magnitude-limited galaxy catalogs. Here, we do the first analysis ofN-body simulations to predict this fraction, finding ∼73% should have associated groups and group averaging should improve redshift precision by ∼135 km s⁻¹(∼0.04 mag atz= 0.025). Furthermore, using spectroscopic data from the Anglo-Australian Telescope, we present results from the first pilot program to evaluate whether or not 23 previously unassociated SN Ia hosts belong in groups. We find that 91% of these candidates can be associated with groups, consistent with predictions from simulations given the sample size. Combining with previously assigned SN host galaxies in Pantheon+, we demonstrate improvement in Hubble residual scatter equivalent to 145 km s⁻¹, also consistent with simulations. For new and upcoming low-zsamples from, for example, the Zwicky Transient Facility and the Legacy Survey of Space and Time, a separate follow-up program identifying galaxy groups of SN hosts is a highly cost-effective way to enhance their constraining power. 

Abstract The Dark Energy Spectroscopic Instrument (DESI) collaboration measured a tight relation between the Hubble constant (H₀) and the distance to the Coma cluster using the fundamental plane (FP) relation of the deepest, most homogeneous sample of early-type galaxies. To determineH₀, we measure the distance to Coma by several independent routes, each with its own geometric reference. We measure the most precise distance to Coma from 13 Type Ia supernovae (SNe Ia) in the cluster with a mean standardized brightness of $m_B^0=15.710\pm 0.040$mag. Calibrating the absolute magnitude of SNe Ia with the Hubble Space Telescope (HST) distance ladder yieldsD_Coma = 98.5 ± 2.2 Mpc, consistent with its canonical value of 95–100 Mpc. This distance results inH₀ = 76.5 ± 2.2 km s⁻¹Mpc⁻¹from the DESI FP relation. Inverting the DESI relation by calibrating it instead to the Planck+ΛCDM value ofH₀ = 67.4 km s⁻¹Mpc⁻¹implies a much greater distance to Coma,D_Coma = 111.8 ± 1.8 Mpc, 4.6σbeyond a joint, direct measure. Independent of SNe Ia, the HST Key Project FP relation as calibrated by Cepheids, the tip of the red giant branch from JWST, or HST near-infrared surface brightness fluctuations all yieldD_Coma < 100 Mpc, in joint tension themselves with the Planck-calibrated route at >3σ. From a broad array of distance estimates compiled back to 1990, it is hard to see how Coma could be located as far as the Planck+ΛCDM expectation of >110 Mpc. By extending the Hubble diagram to Coma, a well-studied location in our own backyard whose distance was in good accord well before the Hubble tension, DESI indicates a more pervasive conflict between our knowledge of local distances and cosmological expectations. We expect future programs to refine the distance to Coma and nearer clusters to help illuminate this new local window on the Hubble tension. 

Communities of practice (CoPs) play a crucial role in cross-pollination and learning within various skill-based and craft domains. These communities often share common materials, concepts, and techniques across related practices. However, due to their insular nature, exchanging knowledge between CoPs has been challenging, leading to fragmented knowledge marked by differing vocabularies and contexts. To address this issue, we introduce Anther, a system designed to highlight shared concepts and semantic overlap between distinct CoPs. Anther projects concepts onto a 2-dimensional space, providing users with comprehensive, contextual, and conceptual views. We conducted a user study, demonstrating Anther’s effectiveness in aggregating and disseminating community-based knowledge, bridging gaps between CoPs, and supporting the cross-pollination of knowledge between CoPs. Further, we present interaction vignettes that illustrate how Anther can ease entry into new domains and aide in discovering new creative techniques. This work can benefit maker communities by fostering collaborative knowledge-building across diverse domains. 

Within various creative domains, communities of practice (CoPs) are instrumental in fostering knowledge creation and innovation. Although each community disseminates knowledge through resources like online video tutorials, this content is often hidden behind different contexts and semantics that limits practitioners’ ability to learn, borrow, and adapt knowledge from each other. To trace how knowledge disseminates across CoPs, we analyzed video transcripts across 25 communities and characterized them using Term Frequency Proportional Document Frequency (TF*PDF) to extracted materials, tools, and techniques concepts. Using a cluster heatmap visualization, we reveal material and material parallels as boundaries for umbrella CoPs, techniques as strong predictors of kindred CoPs, and outliers as emerging sites of hybrid CoPs. We discuss implications for the design of knowledge discovery support tools to characterize material workflows, track knowledge evolution, and develop semantic vocabularies.