The Australian SKA Pathfinder (ASKAP) has surveyed the sky at multiple frequencies as part of the Rapid ASKAP Continuum Survey (RACS). The first two RACS observing epochs, at 887.5 (RACS-low) and 1 367.5 (RACS-mid) MHz, have been released (McConnell, et al. 2020, PASA, 37, e048; Duchesne, et al. 2023, PASA, 40, e034). A catalogue of radio sources from RACS-low has also been released, covering the sky south of declination $+30^{\circ}$ (Hale, et al., 2021, PASA, 38, e058). With this paper, we describe and release the first set of catalogues from RACS-mid, covering the sky below declination $+49^{\circ}$. The catalogues are created in a similar manner to the RACS-low catalogue, and we discuss this process and highlight additional changes. The general purpose primary catalogue covering 36 200 deg$^2$ features a variable angular resolution to maximise sensitivity and sky coverage across the catalogued area, with a median angular resolution of $11.2^{\prime\prime} \times 9.3^{\prime\prime}$. The primary catalogue comprises 3 105 668 radio sources, including those in the Galactic Plane (2 861 923 excluding Galactic latitudes of $|b|<5^{\circ}$), and we estimate the catalogue to be 95% complete for sources above 2 mJy. With the primary catalogue, we also provide two auxiliary catalogues. The first is a fixed-resolution, 25-arcsec catalogue approximately matching the sky coverage of the RACS-low catalogue. This 25-arcsec catalogue is constructed identically to the primary catalogue, except images are convolved to a less-sensitive 25-arcsec angular resolution. The second auxiliary catalogue is designed for time-domain science and is the concatenation of source lists from the original RACS-mid images with no additional convolution, mosaicking, or de-duplication of source entries to avoid losing time-variable signals. All three RACS-mid catalogues, and all RACS data products, are available through the CSIRO ASKAP Science Data Archive (https://research.csiro.au/casda/).

The Australian SKA Pathfinder (ASKAP) is being used to undertake a campaign to rapidly survey the sky in three frequency bands across its operational spectral range. The first pass of the Rapid ASKAP Continuum Survey (RACS) at 887.5 MHz in the low band has already been completed, with images, visibility datasets, and catalogues made available to the wider astronomical community through the CSIRO ASKAP Science Data Archive (CASDA). This work presents details of the second observing pass in the mid band at 1367.5 MHz, RACS-mid, and associated data release comprising images and visibility datasets covering the whole sky south of $\delta_{\text{J2000}}=+49^\circ$. This data release incorporates selective peeling to reduce artefacts around bright sources, as well as accurately modelled primary beam responses. The Stokes I images reach a median noise of 198 $\mu$Jy PSF$^{-1}$ with a declination-dependent angular resolution of 8.1–47.5 arcsec that fills a niche in the existing ecosystem of large-area astronomical surveys. We also supply Stokes V images after application of a widefield leakage correction, with a median noise of 165 $\mu$Jy PSF$^{-1}$. We find the residual leakage of Stokes I into V to be $\lesssim 0.9$–$2.4$% over the survey. This initial RACS-mid data release will be complemented by a future release comprising catalogues of the survey region. As with other RACS data releases, data products from this release will be made available through CASDA.

The Rapid ASKAP Continuum Survey (RACS) is the first large sky survey using the Australian Square Kilometre Array Pathfinder (ASKAP), covering the sky south of $+41^\circ$ declination. With ASKAP’s large, instantaneous field of view, ${\sim}31\,\mathrm{deg}^2$, RACS observed the entire sky at a central frequency of 887.5 MHz using 903 individual pointings with 15 minute observations. This has resulted in the deepest radio survey of the full Southern sky to date at these frequencies. In this paper, we present the first Stokes I catalogue derived from the RACS survey. This catalogue was assembled from 799 tiles that could be convolved to a common resolution of $25^{\prime\prime}$, covering a large contiguous region in the declination range $\delta=-80^{\circ}$ to $+30^\circ$. The catalogue provides an important tool for both the preparation of future ASKAP surveys and for scientific research. It consists of $\sim$2.1 million sources and excludes the $|b|<5^{\circ}$ region around the Galactic plane. This provides a first extragalactic catalogue with ASKAP covering the majority of the sky ($\delta<+30^{\circ}$). We describe the methods to obtain this catalogue from the initial RACS observations and discuss the verification of the data, to highlight its quality. Using simulations, we find this catalogue detects 95% of point sources at an integrated flux density of $\sim$5 mJy. Assuming a typical sky source distribution model, this suggests an overall 95% point source completeness at an integrated flux density $\sim$3 mJy. The catalogue will be available through the CSIRO ASKAP Science Data Archive (CASDA).

Dietary acculturation may explain the increasing risk of diet-related diseases among African immigrants in the United States (US). We interviewed twenty-five Ghanaian immigrants (Youth n 13, Age (Mean ± sd) 20 y ± 5⋅4, Parents (n 6) and Grandparents (n 6) age 58⋅7 ± 9⋅7) living in New York City (NYC) to (a) understand how cultural practices and the acculturation experience influence dietary patterns of Ghanaian immigrants and (b) identify intergenerational differences in dietary acculturation among Ghanaian youth, parents and grandparents. Dietary acculturation began in Ghana, continued in NYC and was perceived as a positive process. At the interpersonal level, parents encouraged youth to embrace school lunch and foods outside the home. In contrast, parents preferred home-cooked Ghanaian meals, yet busy schedules limited time for cooking and shared meals. At the community level, greater purchasing power in NYC led to increased calories, and youth welcomed individual choice as schools and fast food exposed them to new foods. Global forces facilitated nutrition transition in Ghana as fast and packaged foods became omnipresent in urban settings. Adults sought to maintain cultural foodways while facilitating dietary acculturation for youth. Both traditional and global diets evolved as youth and adults adopted new food and healthy social norms in the US.

The Rapid ASKAP Continuum Survey (RACS) is the first large-area survey to be conducted with the full 36-antenna Australian Square Kilometre Array Pathfinder (ASKAP) telescope. RACS will provide a shallow model of the ASKAP sky that will aid the calibration of future deep ASKAP surveys. RACS will cover the whole sky visible from the ASKAP site in Western Australia and will cover the full ASKAP band of 700–1800 MHz. The RACS images are generally deeper than the existing NRAO VLA Sky Survey and Sydney University Molonglo Sky Survey radio surveys and have better spatial resolution. All RACS survey products will be public, including radio images (with $\sim$ 15 arcsec resolution) and catalogues of about three million source components with spectral index and polarisation information. In this paper, we present a description of the RACS survey and the first data release of 903 images covering the sky south of declination $+41^\circ$ made over a 288-MHz band centred at 887.5 MHz.

Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.

Innovation Concept: Research training programs for students, especially in emergency medicine (EM), may be difficult to initiate due to lack of protected time, resources, and mentors (Chang Y, Ramnanan CJ. Academic Medicine 2015). We developed a ten-week summer program for medical students aimed at cultivating research skills through mentorship, clinical enrichment, and immersion in EM research culture through shadowing and project support. Methods: Five second year Ontario medical students were recruited to participate in the Summer Training and Research in Emergency Medicine (STAR-EM) program at University Health Network, Toronto, from June - Aug, 2019. Program design followed review of existing summer research programs and literature regarding challenges to EM research (McRae, Perry, Brehaut et al. CJEM 2018). The program had broad emergency physician (EP) engagement, with five EP research project mentors, and over ten EPs delivering academic sessions. Curriculum development was collaborative and iterative. All projects were approved by the hospital Research Ethics Board (REB). Curriculum, Tool or Material: Each weekly academic morning comprised small group teaching (topics including research methodology, manuscript preparation, health equity, quality improvement, and wellness), followed by EP-led group progress review of each student's project. Each student spent one half day per week in the emergency department (ED), shadowing an EP and identifying patients for recruitment for ongoing mentor-initiated ED research projects. Remaining time was spent on independent student project work. Presentation to faculty and program evaluation occurred in week 10. Scholarly output included one abstract submitted for publication per student. Program evaluation by students reflected a uniform impression that course material and mentorship were each excellent (100%, n = 5). Interest in pursuing academic EM as a career was identified by all students. Faculty researchers rated the program as very effective (80%, n = 4) or somewhat effective (20%, n = 1) in terms of enhancing productivity and scholarly output. Conclusion: The STAR-EM program provides a transferable model for other academic departments seeking to foster the development of future clinician investigators and enhance ED research culture. Program challenges included delays in REB approval for student projects and engaging recalcitrant staff to participate in research.

The Atacama Large (Sub-)millimeter Array (ALMA) has provided glimpse of the interstellar medium (ISM) properties of galaxies at the Epoch of Reionization (EoR); however, detailed understanding of their internal structure is still lacking. We present properties of molecular cloud complexes (MCCs) in a prototypical galaxy at this epoch studied in cosmological zoom-in simulations (Leung et al. 2019c). Typical MCC mass and size are comparable to nearby spirals and starburst galaxies (Mgas∼106.5Mȯ and R≃45–100 pc). MCCs are highly supersonic, with velocity dispersion of σgas≃20–100 km s−1 and pressure of P/kB ≃107.6Kcm−3, which are comparable to gas-rich starburst galaxies. In addition, we perform stability analysis to understand the origin and dynamical properties of MCCs. We find that MCCs are globally stable in the main disk of Althæa. Densest regions where star formation is expected to take place in clumps and cores on even smaller scales instead have lower virial parameter and Toomre-Q values. Detailed studies of the star-forming gas dynamics at the EoR thus require a spatial resolution of < 40 pc ( ≃ 0.01″), which is within reach of ALMA, to complement studies of stellar populations at EoR using the James Webb Space Telescope (JWST).

Mycobacterium marinum, a bacterium found in freshwater and saltwater, can infect persons with direct exposure to fish or aquariums. During December 2013, the New York City Department of Health and Mental Hygiene learned of four suspected or confirmed M. marinum skin or soft tissue infections (SSTIs) among persons who purchased whole fish from Chinese markets. Ninety-eight case-patients with non-tuberculous mycobacteria (NTM) SSTIs were identified with onset June 2013–March 2014. Of these, 77 (79%) were female. The median age was 62 years (range 30–91). Whole genome sequencing of clinical isolates revealed two main clusters and marked genetic diversity. Environmental samples from distributors yielded NTM though not M. marinum. We compared 56 case-patients with 185 control subjects who shopped in Chinese markets, frequency-matched by age group and sex. Risk factors for infection included skin injury to the finger or hand (odds ratio [OR]: 15·5; 95% confidence interval [CI]: 6·9–37·3), hand injury while preparing fish or seafood (OR 8·3; 95% CI 3·8–19·1), and purchasing tilapia (OR 3·6; 95% CI 1·1–13·9) or whiting (OR 2·7; 95% CI 1·1–6·6). A definitive environmental outbreak source was not identified.

We examined the impact of the neonatal hepatitis B immunization programme, first provided to all neonates born to mothers screened positive for hepatitis B surface antigen (HBsAg) in late 1983, on the age-specific prevalence of HBsAg carriage in teenage mothers managed in 1998–2008. HBsAg carriage was found in 2·5%, 2·7%, 8·8% and 8·0% of mothers aged ⩽16, 17, 18, and 19 years, respectively (P = 0·004), which was also correlated with advancing age (P = 0·011). While neither difference nor correlation with age was found in mothers born before 1984, the prevalence of 1·2%, 1·5%, 7·1% and 8·3%, respectively, was significantly different among (P = 0·008) and correlated with (P = 0·002) age in mothers born 1984 onwards. Regression analysis indicated there was a significantly higher incidence of HBsAg carriage from age 17 onwards (adjusted odds ratio 2·55, 95% confidence interval 1·07–6·10, P = 0·035), suggesting that the protective effect of the vaccine declined in late adolescence.

Background: The Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery (CERAD-NAB) offers information on the clinical diagnosis of Alzheimer's disease (AD) and gives a profile of cognitive functioning. This study explores the effects of age, education and gender on participants' performance on eight subtests in the Chinese-Cantonese version of the CERAD-NAB.

Methods: The original English version of the CERAD-NAB was translated and content-validated into a Chinese-Cantonese version to suit the Hong Kong Chinese population. The battery was administered to 187 healthy volunteers aged 60 to 94 years. Participants were excluded if they had neurological, medical or psychiatric disorders (including dementia). Stepwise multiple linear regression analyses were performed to assess the relative contribution of the demographic variables to the scores on each subtest.

Results: The Cantonese version of CERAD-NAB was shown to have good content validity and excellent inter-rater reliability. Stepwise multiple regression analyses revealed that performances on seven and four out of eight subtests in the CERAD-NAB were significantly influenced by education level and age, respectively. Age and education had significant effects on participants' performance on many tests. Gender also showed a significant effect on one subtest.

Conclusions: The preliminary data will serve as an initial phase for clinical interpretation of the CERAD-NAB for Cantonese-speaking Chinese elders.

Background: Growing evidence suggests that participation in late-life leisure activity may have beneficial effects on cognitive function. The objective of the study was to evaluate the association between leisure activity participation and cognitive function in an elderly population of community-dwelling Hong Kong Chinese.

Methods: 512 participants were assessed in the follow-up study of a population-based community survey of the prevalence of cognitive impairment among Hong Kong Chinese aged 60 years and over. Leisure activities were classified into four categories (physical, intellectual, social and recreational). Information regarding leisure activity participation, cognitive function and other variables was collected. Multivariate linear regression analyses were performed to examine the association between leisure activity participation and cognitive function.

Results: A higher level of late-life leisure activity participation, particularly in intellectual activities, was significantly associated with better cognitive function in the elderly, as reflected by the results of the Cantonese Mini-mental State Examination (p = 0.007, 0.029 and 0.005), the Category Verbal Fluency Test (p = 0.027, 0.003 and 0.005) and digit backward span (p = 0.031, 0.002 and 0.009), as measured by the total frequency, total hours per week and total number of subtypes, respectively; the Chinese Alzheimer's Disease Assessment Scale-Cognitive Subscale (p = 0.045) and word list learning (p = 0.003), as measured by the total number of subtypes; and digit forward span (p = 0.007 and 0.015), as measured by the total hours per week and total number of subtypes, respectively.

Conclusion: Late-life intellectual activity participation was associated with better cognitive function among community-dwelling Hong Kong elderly Chinese.