The First Large Absorption Survey in H i (FLASH) is a large-area radio survey for neutral hydrogen in and around galaxies in the intermediate redshift range $0.4\lt z\lt1.0$, using the 21-cm H i absorption line as a probe of cold neutral gas. The survey uses the ASKAP radio telescope and will cover 24,000 deg$^2$ of sky over the next five years. FLASH breaks new ground in two ways – it is the first large H i absorption survey to be carried out without any optical preselection of targets, and we use an automated Bayesian line-finding tool to search through large datasets and assign a statistical significance to potential line detections. Two Pilot Surveys, covering around 3000 deg$^2$ of sky, were carried out in 2019-22 to test and verify the strategy for the full FLASH survey. The processed data products from these Pilot Surveys (spectral-line cubes, continuum images, and catalogues) are public and available online. In this paper, we describe the FLASH spectral-line and continuum data products and discuss the quality of the H i spectra and the completeness of our automated line search. Finally, we present a set of 30 new H i absorption lines that were robustly detected in the Pilot Surveys, almost doubling the number of known H i absorption systems at $0.4\lt z\lt1$. The detected lines span a wide range in H i optical depth, including three lines with a peak optical depth $\tau\gt1$, and appear to be a mixture of intervening and associated systems. Interestingly, around two-thirds of the lines found in this untargeted sample are detected against sources with a peaked-spectrum radio continuum, which are only a minor (5–20%) fraction of the overall radio-source population. The detection rate for H i absorption lines in the Pilot Surveys (0.3 to 0.5 lines per 40 deg$^2$ ASKAP field) is a factor of two below the expected value. One possible reason for this is the presence of a range of spectral-line artefacts in the Pilot Survey data that have now been mitigated and are not expected to recur in the full FLASH survey. A future paper in this series will discuss the host galaxies of the H i absorption systems identified here.

The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.

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.

Analyzing historical trajectories of social interactions at varying scales can lead to complementary interpretations of relationships among archaeological settlements. We use social network analysis combined with geographic information systems at three spatial scales over time in the western U.S. Southwest to show how the same social processes affected network dynamics at each scale. The period we address, A.D. 1200–1450, was characterized by migration and demographic upheaval. The tumultuous late thirteenth-century interval was followed by population coalescence and the development of widespread religious movements in the fourteenth and fifteenth centuries. In the southern Southwest these processes resulted in a highly connected network that drew in members of different settlements within and between different valleys that had previously been distinct. In the northern Southwest networks were initially highly connected followed by a more fragmented social landscape. We examine how different network textures emerged at each scale through 50-year snapshots. The results demonstrate the usefulness of applying a multiscalar approach to complex historical trajectories and the potential for social network analysis as applied to archaeological data.

The purpose of the present review is to highlight some of the challenges and issues in developing nutritional guidelines for companion animals, and to provide some insights that may influence their future direction. For this purpose, we have chosen to provide a brief historical review of the development of dog and cat nutrient guidelines, and an analysis of current recommendations and of key institutions and bodies (notably the National Research Council) that are influential in defining nutrient guidelines for companion animals. In addition, we have also included a review of current approaches for defining nutritional guidelines for humans and farm animal livestock, as they provide differing perspectives and insights that may be instructive for the future development of nutritional guidelines for companion animals.