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Abstract Phosphorus is a key element that plays an essential role in biological processes important for living organisms on Earth. The origin and connection of phosphorus-bearing molecules to early solar system objects and star-forming molecular clouds is therefore of great interest, yet there are limited observations throughout different stages of low-mass (M < a few solar masses) star formation. Observations from the Yebes 40 m and IRAM 30 m telescopes detect for the first time in the 7 mm, 3 mm, and 2 mm bands multiple transitions of PN and PO, as well as a single transition of PO⁺, toward a low-mass starless core. The presence of PN, PO, and PO⁺is kinematically correlated with bright SiO(1–0) emission. Our results reveal not only that shocks are the main driver of releasing phosphorus from dust grains and into the gas phase but that the emission originates from gas not affiliated with the shock itself but quiescent gas that has been shocked in the recent past. From radiative transfer calculations, the PO/PN abundance ratio is found to be $3.1_{-0.6}^{+0.4}$, consistent with other high-mass and low-mass star-forming regions. This first detection of PO⁺toward any low-mass star-forming region reveals a PO⁺/PO ratio of $0.0115_{-0.0009}^{+0.0008}$, a factor of 10 lower than previously determined from observations of a Galactic center molecular cloud, suggesting its formation can occur under more standard Galactic cosmic-ray ionization rates. These results motivate the need for additional observations that can better disentangle the physical mechanisms and chemical drivers of this precursor of prebiotic chemistry. 

ABSTRACT Metagenomics is a powerful tool for characterising viruses, with broad applications across diverse disciplines, from understanding the ecology and evolutionary history of viruses to identifying causative agents of emerging outbreaks with unknown aetiology. Additionally, metagenomic data contains valuable information about the amount of virus present within samples. However, we have yet to leverage metagenomics to assess viral load, which is a key epidemiological parameter. To effectively use sequencing outputs to inform transmission, we need to understand the relationship between read depth and viral load across a diverse set of viruses. Here, using target enrichment sequencing, we investigated the detection and recovery of virus genomes by spiking known concentrations of DNA and RNA viruses into wild rodent faecal samples. In total, 15 experimental replicates were sequenced with target enrichment sequencing and compared to shotgun sequencing of the same background samples. Target enriched sequencing recovered all spike-in viruses at every concentration (10², 10³, and 10⁵± 1 log genome copies) and showed a log-linear relationship between spike-in concentration and mean read depth. Background viruses (includingKobuvirusandCardiovirus) were recovered consistently across all biological and technical replicates, but genome coverage was variable between virus genera and likely reflected the composition of target enrichment probe panel. Overall, our study highlights the strengths and weaknesses of using commercially available panels to quantify and characterise wildlife viromes, and underscores the importance of probe panel design for accurately interpreting coverage and read depth. To advance the use of metagenomics for understanding virus transmission, further research will be needed to elucidate how sequencing strategy (e.g. library depth, pooling), virome composition, and probe design influence viral read counts and genome coverage. 

Interrupting pathogen transmission between species is a priority strategy to mitigate zoonotic threats. However, avoiding counterproductive interventions requires knowing animal reservoirs of infection and the dynamics of transmission within them, neither of which are easily ascertained from the cross-sectional surveys that now dominate investigations into newly discovered viruses. We used biobanked sera and metagenomic data to reconstruct the transmission of recently discovered bat-associated influenza virus (BIV; H18N11) over 12 years in three zones of Peru. Mechanistic models fit under a Bayesian framework, which enabled joint inference from serological and molecular data, showed that common vampire bats maintain BIV independently of the now assumed fruit bat reservoir through immune waning and seasonal transmission pulses. A large-scale vampire bat cull targeting rabies incidentally halved BIV transmission, confirming vampire bats as maintenance hosts. Our results show how combining field studies, perturbation responses, and multi-data–type models can elucidate pathogen dynamics in nature and reveal pathogen-dependent effects of interventions. 

Most current statistics courses include some instruction relevant to causal inference. Whether this instruction is incorporated as material on randomized experiments or as an interpretation of associations measured by correlation or regression coefficients, the way in which this material is presented may have important implications for understanding causal inference fundamentals. Although the connection between study design and the ability to infer causality is often described well, the link between the language used to describe study results and causal attribution typically is not well defined. The current study investigates this relationship experimentally using a sample of students in a statistics course at a large western university in the United States. It also provides (non-experimental) evidence about the association between statistics instruction and the ability to understand appropriate causal attribution. The results from our experimental vignette study suggest that the wording of study findings impacts causal attribution by the reader, and, perhaps more surprisingly, that this variation in level of causal attribution across different wording conditions seems to pale in comparison to the variation across study contexts. More research, however, is needed to better understand how to tailor statistics instruction to make students sufficiently wary of unwarranted causal interpretation. 

Wearable electronics expand the ways learners can create with computing as they gain proficiency with programming and electronics. Dance is one domain where wearables can support creative, embodied practices in computing education. However, wearable electronics need to be small, durable, and easily integrated into clothing to meet the constraints of dance contexts. These features are challenging to achieve, especially when working with novices. We present DanceBits, a wearable prototyping kit for dance that was co-developed with a justice-oriented, computing and dance education organization. DanceBits’ plug-and-play system uses small PCBs with solderless connectors to support dancers in rapidly designing, building, and performing with electronic costumes. Our user studies exploring the system with dance instructors and youth participants show that DanceBits enabled fast development of wearables, offered users a breadth of expressivity through computational and choreographic choices, and empowered dancers to see wearables as a tool for developing their movement practices. 

Performing arts computing environments have received little attention in the educational sphere; yet, they offer opportunities for learners to validate their efforts, ideas, and skills through showcasing their work in a public-facing performance. In this work, we explore an out-of-school dance and computing educational program run by the organization, STEM From Dance. The organizational mission is to create an equitable learning experience for young women of color to engage with computing while exposing them to STEM careers. Through an analysis of eleven interviews with youth participants, instructors, and the executive director, we examine how the social, cultural, and political dimensions of the learning environment facilitate identity work in computing and dance. Our findings point to three primary activities used by the organization to promote equity: (1) providing psychological safety through a supportive community environment, (2) meaningfully engaging with learners’ social and cultural context through creative work with constructionist artifacts, and (3) actively promoting identity work as women of color in computing and STEM through both artifact work and community events. Applying the constructs of identity and psychological safety we explore the tensions and synergies of designing for equity in this performing arts and computing learning environment. We demonstrate how the seemingly contradictory elements of a high-stakes performance within a novice learning environment provides unique opportunities for supporting young women of color in computing, making them non-negotiable in the organization’s efforts to promote equity and inclusion. Our work illustrates how attending closely to the sociocultural dimensions in a constructionist learning environment provides lenses for navigating equity, identity work, and support for inclusive computing.