We present the Evolutionary Map of the Universe (EMU) survey conducted with the Australian Square Kilometre Array Pathfinder (ASKAP). EMU aims to deliver the touchstone radio atlas of the southern hemisphere. We introduce EMU and review its science drivers and key science goals, updated and tailored to the current ASKAP five-year survey plan. The development of the survey strategy and planned sky coverage is presented, along with the operational aspects of the survey and associated data analysis, together with a selection of diagnostics demonstrating the imaging quality and data characteristics. We give a general description of the value-added data pipeline and data products before concluding with a discussion of links to other surveys and projects and an outline of EMU’s legacy value.

The scatter in global atomic hydrogen (Hi) scaling relations is partly attributed to differences in how Hi and stellar properties are measured, with Hi reservoirs typically extending beyond the inner regions of galaxies where star formation occurs. Using pilot observations from the Widefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY), we present the first measurements of Hi mass enclosed within the stellar-dominated regions of galaxies for a statistical sample of 995 local gas-rich systems, investigating the factors driving its variation. We examine how global Hi scaling relations change when measurements are restricted to $R_{\text{25}}$ and $R_{\text{24}}$ – the isophotal radii at 25 and 24 mag arcsec$^{-2}$ in the i-band – and explore how the fraction of Hi mass and Hi surface density within these radii correlate with other galaxy properties. On average, 68% of the total Hi mass is enclosed within $R_{\text{25}}$ and 54% within $R_{\text{24}}$, though significant variation exists between galaxies, ranging from $\sim$20% to 100%. The fraction of Hi mass within $R_{\text{25}}$ shows a mild correlation with stellar properties, with galaxies of higher stellar mass, greater stellar surface density, or redder colours enclosing a larger fraction of their Hi reservoirs. These correlations do not significantly strengthen when considering $R_{\text{24}}$. Conversely, global Hi surface densities show no significant correlation with stellar mass or stellar surface density, but trends start emerging when these are measured within the inner regions of galaxies. The strongest correlation is observed with optical colour, with bluer galaxies having higher average Hi surface densities within $R_{\text{25}}$. This trend of the average Hi surface density with optical colour strengthens when we restrict from $R_{\text{25}}$ to $R_{\text{24}}$, suggesting a closer connection between inner Hi reservoirs and star formation. This study underscores the value of (at least marginally) resolved Hi surveys of statistical samples for advancing our understanding of the gas-star formation cycle in galaxies.

An important component of post-release monitoring of biological control of invasive plants is the tracking of species interactions. During post-release monitoring following the initial releases of the weevil Ceutorhynchus scrobicollis Nerenscheimer and Wagner (Coleoptera: Curculionidae) on garlic mustard, Alliaria petiolata (Marschall von Bieberstein) Cavara and Grande (Brassicaceae), in Ontario, Canada, we identified the presence of larvae of the tumbling flower beetle, Mordellina ancilla Leconte (Coleoptera: Mordellidae), in garlic mustard stems. This study documents the life history of M. ancilla on garlic mustard to assess for potential interactions between M. ancilla and C. scrobicollis as a biological control agent. Garlic mustard stems were sampled at eight sites across southern Ontario and throughout the course of one year to record the prevalence of this association and to observe its life cycle on the plant. We found M. ancilla to be a widespread stem-borer of late second–year and dead garlic mustard plants across sampling locations. This is the first host record for M. ancilla on garlic mustard. The observed life cycle of M. ancilla indicates that it is unlikely to negatively impact the growth and reproduction of garlic mustard and that it is unlikely to affect the use of C. scrobicollis as a biological control agent.

Herbaceous perennials must annually rebuild the aboveground photosynthetic architecture from carbohydrates stored in crowns, rhizomes, and roots. Knowledge of carbohydrate utilization and storage can inform management decisions and improve control outcomes for invasive perennials. We monitored the nonstructural carbohydrates in a population of the hybrid Bohemian knotweed [Polygonum ×bohemicum (J. Chrtek & Chrtková) Zika & Jacobson [cuspidatum × sachalinense]; syn.: Fallopia ×bohemica (Chrtek and Chrtková) J.P. Bailey] and in Japanese knotweed [Polygonum cuspidatum Siebold & Zucc.; syn.: Fallopia japonica (Houtt.) Ronse Decr.]. Carbohydrate storage in crowns followed seasonal patterns typical of perennial herbaceous dicots corresponding to key phenological events. Starch was consistently the highest nonstructural carbohydrate present. Sucrose levels did not show a consistent inverse relationship with starch levels. Lateral distribution of starch in rhizomes and, more broadly, total nonstructural carbohydrates sampled before dormancy break showed higher levels in rhizomes compared with crowns. Total nonstructural carbohydrate levels in crowns reached seasonal lows at an estimated 22.6% of crown dry weight after accumulating 1,453.8 growing degree days (GDD) by the end of June, mainly due to depleted levels of stored starch, with the estimated minimum of 12.3% reached by 1,220.3 GDD accumulated by mid-June. Depletion corresponded to rapid development of vegetative canopy before entering the reproductive phase in August. Maximum starch accumulation in crowns followed complete senescence of aboveground tissues by mid- to late October. Removal of aboveground shoot biomass in late June to early July with removal of vegetation regrowth in early September before senescence would optimize the use of time and labor to deplete carbohydrate reserves. Additionally, foliar-applied systemic herbicide translocation to belowground tissue should be maximized with applications in late August through early fall to optimize downward translocation with assimilate movement to rebuild underground storage reserves. Fall applications should be made before loss of healthy leaf tissue, with the window for control typically ending by late September in Minnesota.

Objectives/Goals: We describe the prevalence of individuals with household exposure to SARS-CoV-2, who subsequently report symptoms consistent with COVID-19, while having PCR results persistently negative for SARS-CoV-2 (S[+]/P[-]). We assess whether paired serology can assist in identifying the true infection status of such individuals. Methods/Study Population: In a multicenter household transmission study, index patients with SARS-CoV-2 were identified and enrolled together with their household contacts within 1 week of index’s illness onset. For 10 consecutive days, enrolled individuals provided daily symptom diaries and nasal specimens for polymerase chain reaction (PCR). Contacts were categorized into 4 groups based on presence of symptoms (S[+/-]) and PCR positivity (P[+/-]). Acute and convalescent blood specimens from these individuals (30 days apart) were subjected to quantitative serologic analysis for SARS-CoV-2 anti-nucleocapsid, spike, and receptor-binding domain antibodies. The antibody change in S[+]/P[-] individuals was assessed by thresholds derived from receiver operating characteristic (ROC) analysis of S[+]/P[+] (infected) versusS[-]/P[-] (uninfected). Results/Anticipated Results: Among 1,433 contacts, 67% had ≥1 SARS-CoV-2 PCR[+] result, while 33% remained PCR[-]. Among the latter, 55% (n = 263) reported symptoms for at least 1 day, most commonly congestion (63%), fatigue (63%), headache (62%), cough (59%), and sore throat (50%). A history of both previous infection and vaccination was present in 37% of S[+]/P[-] individuals, 38% of S[-]/P[-], and 21% of S[+]/P[+] (P<0.05). Vaccination alone was present in 37%, 41%, and 52%, respectively. ROC analyses of paired serologic testing of S[+]/P[+] (n = 354) vs. S[-]/P[-] (n = 103) individuals found anti-nucleocapsid data had the highest area under the curve (0.87). Based on the 30-day antibody change, 6.9% of S[+]/P[-] individuals demonstrated an increased convalescent antibody signal, although a similar seroresponse in 7.8% of the S[-]/P[-] group was observed. Discussion/Significance of Impact: Reporting respiratory symptoms was common among household contacts with persistent PCR[-] results. Paired serology analyses found similar seroresponses between S[+]/P[-] and S[-]/P[-] individuals. The symptomatic-but-PCR-negative phenomenon, while frequent, is unlikely attributable to true SARS-CoV-2 infections that go missed by PCR.

When and why did House parties identify exclusive committees? The nexus of parties and standing committees defines the distribution of power in the U.S. House of Representatives, shapes legislators’ careers, and affects Congress's ability to address the nation's problems. Yet, political science provides inadequate and often misleading characterizations of the parties and the most important standing committees. We provide missing detail and offer a historical perspective on party efforts to arrange standing committees in the period since the revolt against Speaker Joseph Cannon in 1909–1910. Our narrative offers a foundation for explaining party efforts to regulate committee membership and meet legislators’ demands. For the first time, we define three periods in committee assignment limitations. In doing so, we place key events in historical context: We report that the modern exclusive committees (Appropriations, Rules, and Ways and Means) did not become defined until the 1950s; the identification by the two parties of a larger set of exclusive committees for which a one-assignment limitation applied began decades earlier; the Legislative Reorganization Act of 1946 placed a one-assignment limitation in House rules that had been party practice for three decades by then. In recent decades, deep partisanship has been accompanied by a loosening, not tightening, of restrictions. In fact, there are no fully exclusive committees remaining in practice.

Regardless of method, political scientists often seek to develop arguments that can be generalized to a population of cases. But is this the only way to think about how cases speak to one another? We advocate for a new way to think about how qualitative research produces broadly applicable insights: translation. Much like linguistic translation, the goal of translation in political science is to develop ideas that are intelligible in a different context, even as the context will change how an idea or political practice is interpreted or enacted. Translation offers at least three benefits. It allows us to (1) rethink how we form and deploy concepts; (2) rethink what a generalizable argument is by carrying parts of an argument, instead of entire causal chains to other cases; and (3) rethink how we conceptualize knowledge accumulation to include an abductive process where generating theory is the primary goal.

Early detection and active management of invasive group A Streptococcus (iGAS) infection outbreaks are essential. Here, we describe the changing epidemiology of outbreaks of iGAS in England between 2015 and 2019, a period of increasing incidence of iGAS infection. Data on iGAS infections were extracted from national public health management records and laboratory records. Outbreaks were described in size, duration, setting, and emm type. Overall, 194 outbreaks were identified, and reports increased each year, from 16 outbreaks in 2015 to 61 in 2019. The median outbreak size was 3 cases (n = 37; 19%), with 27% of outbreaks recording 4–10 cases (n = 53) and 7% recording more than 10 cases (n = 13). Outbreak duration ranged from 0 to 170 weeks (median 7). Settings of outbreaks changed over the study period, with increasing numbers observed in multiple settings. This study provides new insights into the changing burden of iGAS infection and outbreaks in England.

A central goal in ecology is investigating the impact of major perturbations, such as invasion, on the structure of biological communities. One promising line of inquiry is using co-occurrence analyses to examine how species’ traits mediate coexistence and how major ecological, climatic, and environmental disturbances can affect this relationship and underlying mechanisms. However, present communities are heavily influenced by anthropogenic behaviors and may exhibit greater or lesser resistance to invasion than communities that existed before human arrival. Therefore, to disentangle the impact of individual disturbances on mammalian communities, it is important to examine community dynamics before humans. Here, we use the North American fossil record to evaluate the co-occurrence structure of mammals across the Great American Biotic Interchange. We compiled 126 paleocommunities from the late Pliocene (4–2.5 Ma) and early Pleistocene (2.5–1 Ma). Genus-level co-occurrence was calculated to identify significantly aggregated (co-occur more than expected) and segregated (co-occur less than expected) genus pairs. A functional diversity analysis was used to calculate functional distance between genus pairs to evaluate the relationship between pair association strength and functional role. We found that the strength distribution of aggregating and segregating genus pairs does not significantly change from the late Pliocene to the early Pleistocene, even with different mammals forming the pairs, including immigrant mammals from South America. However, we did find that significant pairs, both aggregations and segregations, became more similar in their functional roles following the Plio-Pleistocene transition. Due to different mammals and ecological roles forming significant associations and the stability of co-occurrence structure across this interval, our study suggests that mammals have fundamental ways of assembling that may have been altered by humans in the present.

The concept of interaction classes (iClasses) for multi-environment trial data was introduced to address the problem of summarising variety performance across environments in the presence of variety by environment interaction (VEI). The approach involves the fitting of a factor analytic linear mixed model (FALMM), with the resultant estimates of factor loadings being used to form groups of environments (iClasses) that discriminate varieties with different patterns of VEI. It is then meaningful to summarise variety performance across environments within iClasses. The iClass methodology was developed with respect to a FALMM in which the genetic effects for different varieties were assumed independent. This was done for pedagogical reasons but it was pointed out that the accuracy of variety selection is greatly enhanced by considering the genetic relatedness of varieties, either via ancestral or genomic information. The focus of the current paper is therefore to extend the iClass approach for FALMMs which incorporate such information. In addition, a measure of stability of variety performance across iClasses is defined. The utility of the approach for variety selection is illustrated using a multi-environment trial dataset from the lentil breeding programme operated by Agriculture Victoria.

Young people with childhood adversity (CA) were at increased risk to experience mental health problems during the COVID-19 pandemic. Pre-pandemic research identified high-quality friendship support as a protective factor that can buffer against the emergence of mental health problems in young people with CA. This longitudinal study investigated friendship buffering effects on mental health symptoms before and at three timepoints during the pandemic in 102 young people (aged 16–26) with low to moderate CA. Multilevel analyses revealed a continuous increase in depression symptoms following the outbreak. Friendship quality was perceived as elevated during lockdowns and returned to pre-pandemic baseline levels during reopening. A stress-sensitizing effect of CA on social functioning was evident, as social thinning occurred following the outbreak. Bivariate latent change score modeling revealed that before and during the pandemic, young people with greater friendship quality self-reported lower depression symptoms and vice versa. Furthermore, sequential mediation analysis showed that high-quality friendships before the pandemic buffered depression symptoms during the pandemic through reducing perceived stress. These findings highlight the importance of fostering stable and supportive friendships in young people with CA and suggest that through reducing stress perceptions high-quality friendships can mitigate mental health problems during times of multidimensional stress.

We report the case of a 16-year-old female with previously diagnosed bilateral sub-segmental pulmonary emboli who presented in cardiogenic shock from depressed biventricular function with cardiac MRI demonstrating concern for microvascular coronary injury. She was ultimately diagnosed with catastrophic antiphospholipid antibody syndrome-induced ischaemic cardiomyopathy, potentially associated with an underlying autoimmune connective tissue disease.

The global population and status of Snowy Owls Bubo scandiacus are particularly challenging to assess because individuals are irruptive and nomadic, and the breeding range is restricted to the remote circumpolar Arctic tundra. The International Union for Conservation of Nature (IUCN) uplisted the Snowy Owl to “Vulnerable” in 2017 because the suggested population estimates appeared considerably lower than historical estimates, and it recommended actions to clarify the population size, structure, and trends. Here we present a broad review and status assessment, an effort led by the International Snowy Owl Working Group (ISOWG) and researchers from around the world, to estimate population trends and the current global status of the Snowy Owl. We use long-term breeding data, genetic studies, satellite-GPS tracking, and survival estimates to assess current population trends at several monitoring sites in the Arctic and we review the ecology and threats throughout the Snowy Owl range. An assessment of the available data suggests that current estimates of a worldwide population of 14,000–28,000 breeding adults are plausible. Our assessment of population trends at five long-term monitoring sites suggests that breeding populations of Snowy Owls in the Arctic have decreased by more than 30% over the past three generations and the species should continue to be categorised as Vulnerable under the IUCN Red List Criterion A2. We offer research recommendations to improve our understanding of Snowy Owl biology and future population assessments in a changing world.