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The Australian SKA Pathfinder (ASKAP) offers powerful new capabilities for studying the polarised and magnetised Universe at radio wavelengths. In this paper, we introduce the Polarisation Sky Survey of the Universe’s Magnetism (POSSUM), a groundbreaking survey with three primary objectives: (1) to create a comprehensive Faraday rotation measure (RM) grid of up to one million compact extragalactic sources across the southern $\sim50$% of the sky (20,630 deg$^2$); (2) to map the intrinsic polarisation and RM properties of a wide range of discrete extragalactic and Galactic objects over the same area; and (3) to contribute interferometric data with excellent surface brightness sensitivity, which can be combined with single-dish data to study the diffuse Galactic interstellar medium. Observations for the full POSSUM survey commenced in May 2023 and are expected to conclude by mid-2028. POSSUM will achieve an RM grid density of around 30–50 RMs per square degree with a median measurement uncertainty of $\sim$1 rad m$^{-2}$. The survey operates primarily over a frequency range of 800–1088 MHz, with an angular resolution of 20” and a typical RMS sensitivity in Stokes Q or U of 18 $\mu$Jy beam$^{-1}$. Additionally, the survey will be supplemented by similar observations covering 1296–1440 MHz over 38% of the sky. POSSUM will enable the discovery and detailed investigation of magnetised phenomena in a wide range of cosmic environments, including the intergalactic medium and cosmic web, galaxy clusters and groups, active galactic nuclei and radio galaxies, the Magellanic System and other nearby galaxies, galaxy halos and the circumgalactic medium, and the magnetic structure of the Milky Way across a very wide range of scales, as well as the interplay between these components. This paper reviews the current science case developed by the POSSUM Collaboration and provides an overview of POSSUM’s observations, data processing, outputs, and its complementarity with other radio and multi-wavelength surveys, including future work with the SKA.
We provide an assessment of the Infinity Two fusion pilot plant (FPP) baseline plasma physics design. Infinity Two is a four-field period, aspect ratio $A = 10$, quasi-isodynamic stellarator with improved confinement appealing to a max-$J$ approach, elevated plasma density and high magnetic fields ($ \langle B\rangle = 9$ T). Here $J$ denotes the second adiabatic invariant. At the envisioned operating point ($800$ MW deuterium-tritium (DT) fusion), the configuration has robust magnetic surfaces based on magnetohydrodynamic (MHD) equilibrium calculations and is stable to both local and global MHD instabilities. The configuration has excellent confinement properties with small neoclassical transport and low bootstrap current ($|I_{bootstrap}| \sim 2$ kA). Calculations of collisional alpha-particle confinement in a DT FPP scenario show small energy losses to the first wall (${\lt}1.5 \,\%$) and stable energetic particle/Alfvén eigenmodes at high ion density. Low turbulent transport is produced using a combination of density profile control consistent with pellet fueling and reduced stiffness to turbulent transport via three-dimensional shaping. Transport simulations with the T3D-GX-SFINCS code suite with self-consistent turbulent and neoclassical transport predict that the DT fusion power$P_{{fus}}=800$ MW operating point is attainable with high fusion gain ($Q=40$) at volume-averaged electron densities $n_e\approx 2 \times 10^{20}$ m$^{-3}$, below the Sudo density limit. Additional transport calculations show that an ignited ($Q=\infty$) solution is available at slightly higher density ($2.2 \times 10^{20}$ m$^{-3}$) with $P_{{fus}}=1.5$ GW. The magnetic configuration is defined by a magnetic coil set with sufficient room for an island divertor, shielding and blanket solutions with tritium breeding ratios (TBR) above unity. An optimistic estimate for the gas-cooled solid breeder designed helium-cooled pebble bed is TBR $\sim 1.3$. Infinity Two satisfies the physics requirements of a stellarator fusion pilot plant.
We present the first results from a new backend on the Australian Square Kilometre Array Pathfinder, the Commensal Realtime ASKAP Fast Transient COherent (CRACO) upgrade. CRACO records millisecond time resolution visibility data, and searches for dispersed fast transient signals including fast radio bursts (FRB), pulsars, and ultra-long period objects (ULPO). With the visibility data, CRACO can localise the transient events to arcsecond-level precision after the detection. Here, we describe the CRACO system and report the result from a sky survey carried out by CRACO at 110-ms resolution during its commissioning phase. During the survey, CRACO detected two FRBs (including one discovered solely with CRACO, FRB 20231027A), reported more precise localisations for four pulsars, discovered two new RRATs, and detected one known ULPO, GPM J1839 $-$10, through its sub-pulse structure. We present a sensitivity calibration of CRACO, finding that it achieves the expected sensitivity of 11.6 Jy ms to bursts of 110 ms duration or less. CRACO is currently running at a 13.8 ms time resolution and aims at a 1.7 ms time resolution before the end of 2024. The planned CRACO has an expected sensitivity of 1.5 Jy ms to bursts of 1.7 ms duration or less and can detect $10\times$ more FRBs than the current CRAFT incoherent sum system (i.e. 0.5 $-$2 localised FRBs per day), enabling us to better constrain the models for FRBs and use them as cosmological probes.
Good nutrition during the postpartum period, which is also the inter-pregnancy period for many women, has short and long-term health benefits for the mother and her offspring(1). Gaining a better understanding of mothers’ dietary patterns at the postpartum stage will help shape appropriate strategies to encourage the adoption of a healthy and more varied diet. This exploration is a preliminary analysis that aims to assess intake of total fat and dietary fibre in a UK cohort of postpartum women with overweight and obesity and examine its relationship with income and ethnicity.
A sample of 892 postpartum women (up to two years after having a baby) with overweight or obesity were recruited from five UK locations (Belfast, Bradford, London, Stirling, Cardiff) to participate in the Supporting MumS (SMS) randomised controlled trial to examine the effectiveness of an automated text-based delivered weight management intervention. At baseline, researchers measured participants’ height and weight and calculated their body mass index (BMI). Baseline diet was self-reported and assessed using the Fat and Fibre Barometer (FFB), a validated scale measuring the consumption frequency of 20 dietary sources of fibre or fat(2). Items were scored from 1-5 and an average FFB score was calculated; greater values indicate a diet higher in fibre-rich foods and lower in fat-rich foods. Information on income and ethnicity was also collected. Multivariable linear regression analysis tested for associations between FFB scores and ethnicity and household income, accounting for BMI, age and study site.
Participants were from a range of ethnicities (Asian: 17%, N = 151; Black: 11%, N = 100; White: 66%, N = 589; Mixed/Other: 6%, N = 52). Household income distribution was: ≤£40K = 41.5%, N = 370; and >£40K = 49.8%, N = 445. Average age was 35 years ranging from 21-57 years. Thirty-nine per cent of women lived with overweight and 61% with obesity. The FFB score was calculated for the 856 of 892 participants who provided complete dietary information (Mean ± SD=3.03 ± 0.42, range: 1.9-4.6). There was no statistically significant association between FFB score and ethnicity.
There was a significant relationship between the FFB score and household income (0.015, P = 0.025, CI = 0.002−0.028), with women from higher incomes having higher FFB scores.
Our results from a large, socioeconomically diverse sample of women with overweight or obesity in the postpartum period showed that mothers from higher income households consumed more fibre and less fat. This is consistent with results of national surveys highlighting the income gradient in food habits and in meeting dietary guidelines among women in the UK(3). Addressing these dietary inequalities will require concerted action from a wide range of stakeholders.
The SMS study is funded by the National Institute for Health Research (Research award: NIHR131509).
Geometric morphometrics facilitates the quantification and visualization of variation in shape and proportion through the comparison of homologous features. Eublastoidea, a Paleozoic echinoderm clade with a conservative body plan, is an ideal group for morphometric analysis, because their plate junctions are homologous and identifiable on all species. Eublastoids have previously been grouped taxonomically by generalized shape types (e.g., globose). These shapes are often used in taxonomic descriptions and as characters in phylogenetic analyses. The underlying homology of these broad shape types has never been explored. Herein we apply the first comprehensive use of three-dimensional geometric morphometrics (3D GMM) on fossil echinoderms to investigate taxonomic assignments, temporal distribution, and whether the varying proportions of skeletal elements that produce the gross thecal morphology are distinguishable. Taxonomic assignments specifically at the ordinal and family levels show varying amounts of overlap in morphospace, suggesting that many assignments may not be reevaluated. Our results suggest that none of the generalized shape types are distinct in morphospace and, therefore, likely do not capture the homologous changes in taxa. The plate circlet ratios showed trends specifically relating to the deltoid plate circlet, which has the most variability. We reanalyzed previous work and subsetted our data to be more comparable and found that there are key differences between methodologies and landmarks that will require future evaluation. Applying modern technological methods to previously explored questions allows for an updated understanding of this important fossil clade and provides a framework for others to assess fossil clades in a similar manner.
The association between cannabis and psychosis is established, but the role of underlying genetics is unclear. We used data from the EU-GEI case-control study and UK Biobank to examine the independent and combined effect of heavy cannabis use and schizophrenia polygenic risk score (PRS) on risk for psychosis.
Methods
Genome-wide association study summary statistics from the Psychiatric Genomics Consortium and the Genomic Psychiatry Cohort were used to calculate schizophrenia and cannabis use disorder (CUD) PRS for 1098 participants from the EU-GEI study and 143600 from the UK Biobank. Both datasets had information on cannabis use.
Results
In both samples, schizophrenia PRS and cannabis use independently increased risk of psychosis. Schizophrenia PRS was not associated with patterns of cannabis use in the EU-GEI cases or controls or UK Biobank cases. It was associated with lifetime and daily cannabis use among UK Biobank participants without psychosis, but the effect was substantially reduced when CUD PRS was included in the model. In the EU-GEI sample, regular users of high-potency cannabis had the highest odds of being a case independently of schizophrenia PRS (OR daily use high-potency cannabis adjusted for PRS = 5.09, 95% CI 3.08–8.43, p = 3.21 × 10−10). We found no evidence of interaction between schizophrenia PRS and patterns of cannabis use.
Conclusions
Regular use of high-potency cannabis remains a strong predictor of psychotic disorder independently of schizophrenia PRS, which does not seem to be associated with heavy cannabis use. These are important findings at a time of increasing use and potency of cannabis worldwide.
Product architecture decisions are made early in the product development process and have far-reaching effects. Unless anticipated through experience or intuition, many of these effects may not be apparent until much later in the development process, making changes to the architecture costly in time, effort and resources. Many researchers through the years have studied various elements of product architecture and their effects. By using a repeatable process for aggregating statements on the effects of architecture strategies from a selection of the literature on the topic and storing them in a systematic database, this information can then be recalled and presented in the form of a Product Architecture Strategy and Effect (PASE) matrix. PASE matrices allow for the identification, comparison, evaluation, and then selection of the most desirable product architecture strategies before expending resources along a specific development path. This paper introduces the PASE Database and matrix and describes their construction and use in guiding design decisions. This paper also provides metrics for understanding the robustness of this database.
Cannabis use and familial vulnerability to psychosis have been associated with social cognition deficits. This study examined the potential relationship between cannabis use and cognitive biases underlying social cognition and functioning in patients with first episode psychosis (FEP), their siblings, and controls.
Methods
We analyzed a sample of 543 participants with FEP, 203 siblings, and 1168 controls from the EU-GEI study using a correlational design. We used logistic regression analyses to examine the influence of clinical group, lifetime cannabis use frequency, and potency of cannabis use on cognitive biases, accounting for demographic and cognitive variables.
Results
FEP patients showed increased odds of facial recognition processing (FRP) deficits (OR = 1.642, CI 1.123–2.402) relative to controls but not of speech illusions (SI) or jumping to conclusions (JTC) bias, with no statistically significant differences relative to siblings. Daily and occasional lifetime cannabis use were associated with decreased odds of SI (OR = 0.605, CI 0.368–0.997 and OR = 0.646, CI 0.457–0.913 respectively) and JTC bias (OR = 0.625, CI 0.422–0.925 and OR = 0.602, CI 0.460–0.787 respectively) compared with lifetime abstinence, but not with FRP deficits, in the whole sample. Within the cannabis user group, low-potency cannabis use was associated with increased odds of SI (OR = 1.829, CI 1.297–2.578, FRP deficits (OR = 1.393, CI 1.031–1.882, and JTC (OR = 1.661, CI 1.271–2.171) relative to high-potency cannabis use, with comparable effects in the three clinical groups.
Conclusions
Our findings suggest increased odds of cognitive biases in FEP patients who have never used cannabis and in low-potency users. Future studies should elucidate this association and its potential implications.
From early on, infants show a preference for infant-directed speech (IDS) over adult-directed speech (ADS), and exposure to IDS has been correlated with language outcome measures such as vocabulary. The present multi-laboratory study explores this issue by investigating whether there is a link between early preference for IDS and later vocabulary size. Infants’ preference for IDS was tested as part of the ManyBabies 1 project, and follow-up CDI data were collected from a subsample of this dataset at 18 and 24 months. A total of 341 (18 months) and 327 (24 months) infants were tested across 21 laboratories. In neither preregistered analyses with North American and UK English, nor exploratory analyses with a larger sample did we find evidence for a relation between IDS preference and later vocabulary. We discuss implications of this finding in light of recent work suggesting that IDS preference measured in the laboratory has low test-retest reliability.
We examined whether cannabis use contributes to the increased risk of psychotic disorder for non-western minorities in Europe.
Methods
We used data from the EU-GEI study (collected at sites in Spain, Italy, France, the United Kingdom, and the Netherlands) on 825 first-episode patients and 1026 controls. We estimated the odds ratio (OR) of psychotic disorder for several groups of migrants compared with the local reference population, without and with adjustment for measures of cannabis use.
Results
The OR of psychotic disorder for non-western minorities, adjusted for age, sex, and recruitment area, was 1.80 (95% CI 1.39–2.33). Further adjustment of this OR for frequency of cannabis use had a minimal effect: OR = 1.81 (95% CI 1.38–2.37). The same applied to adjustment for frequency of use of high-potency cannabis. Likewise, adjustments of ORs for most sub-groups of non-western countries had a minimal effect. There were two exceptions. For the Black Caribbean group in London, after adjustment for frequency of use of high-potency cannabis the OR decreased from 2.45 (95% CI 1.25–4.79) to 1.61 (95% CI 0.74–3.51). Similarly, the OR for Surinamese and Dutch Antillean individuals in Amsterdam decreased after adjustment for daily use: from 2.57 (95% CI 1.07–6.15) to 1.67 (95% CI 0.62–4.53).
Conclusions
The contribution of cannabis use to the excess risk of psychotic disorder for non-western minorities was small. However, some evidence of an effect was found for people of Black Caribbean heritage in London and for those of Surinamese and Dutch Antillean heritage in Amsterdam.
Over the years, so-called univentricular hearts represented one of the greatest challenges for surgical correction. All this changed with the advent of the Fontan procedure,1 along with the realization that it could become the final stage of the sequence of procedures used to correct lesions such as those included in the hypoplastic left heart syndrome,2 which previously had been beyond surgical repair. The overall group of lesions also posed significant problems in adequate description and categorization. Even these days, many continue to describe patients with a double inlet left ventricle as having a single ventricle, despite the fact that, with the availability of clinical diagnostic techniques producing three-dimensional datasets, patients with this lesion can be seen to have two chambers within their ventricular mass, one being large and the other small (Figure 9.1.1). The semantic problems with description can now be resolved by the simple expedient of describing the patients as having functionally univentricular hearts.3
Understanding the anatomy of septal defects is greatly facilitated if the heart is thought of as having three distinct septal structures: the atrial septum, the atrioventricular septum, and the ventricular septum (Figure 8.1.1). The normal atrial septum is relatively small. It is made up, for the most part, by the floor of the oval fossa. When viewed from the right atrial aspect, the fossa has a floor, surrounded by rims. As we have shown in Chapter 2, the floor is derived from the primary atrial septum, or septum primum. Although often considered to represent a secondary septum, or septum secundum, the larger parts of the rims, specifically the superior, antero-superior, and posterior components, are formed by infoldings of the adjacent right and left atrial walls.1 Infero-anteriorly, in contrast, the rim of the fossa is a true muscular septum (Figure 8.1.2).
It is axiomatic that a thorough knowledge of valvar anatomy is a prerequisite for successful surgery, be it valvar replacement or reconstruction. The surgeon will also require a firm understanding of the arrangement of other aspects of cardiac anatomy to ensure safe access to a diseased valve or valves. These features were described in the previous chapter. Knowledge of the surgical anatomy of the valves themselves, however, must be founded on appreciation of their component parts, the relationships of the individual valves to each other, and their relationships to the chambers and arterial trunks within which they reside. This requires understanding of, first, the basic orientation of the cardiac valves, emphasizing the intrinsic features that make each valve distinct from the others. Such information must then be supplemented by attention to their relationships with other structures that the surgeon must avoid, notably the conduction tissues and the major channels of the coronary circulation.
The surgical problems posed by cardiac malformations may be considerably increased when the heart itself is in an abnormal position. This is, in part, due to the unusual anatomical perspective presented to the surgeon because of the malposition, and also to the abnormal locations of the cardiac chambers, which may necessitate approaches other than those already discussed. Cardiac malposition in itself, nonetheless, does not constitute a diagnosis. Any normal or abnormal segmental combination can be found in a heart which itself is abnormally located. The heart may be normal, despite its abnormal location, but extremely complex anomalies are frequently present. Consequently, the very presence of an abnormal cardiac position emphasizes the need for a full and detailed segmental analysis of the heart. All the rules enunciated in Chapter 7 apply should the heart not be in its anticipated position.
Systems for describing congenital cardiac malformations have frequently been based on embryological concepts and theories. As useful as these systems have been, they have often had the effect of confusing the clinician, rather than clarifying the basic anatomy of a given lesion. As far as the surgeon is concerned, the essence of a particular malformation lies not in its presumed morphogenesis, but in the underlying anatomy. An effective system for describing this anatomy must be based on the morphology as it is observed. At the same time, it must be capable of accounting for all congenital cardiac conditions, even those that, as yet, might not have been encountered. To be useful clinically, the system must be not only broad and accurate, but also clear and consistent. The terminology used, therefore, should be unambiguous. It should be as simple as possible. The sequential segmental approach provides such a system.1
The coronary circulation consists of the coronary arteries and veins, together with the lymphatics of the heart. Since the lymphatics, apart from the thoracic duct, are of very limited significance to operative anatomy, they will not be discussed at any length in this chapter. The veins, relatively speaking, are similarly of less interest. In this chapter, therefore, we concentrate on those anatomical aspects of arterial distribution that are pertinent to the surgeon, limiting ourselves to brief discussions of the cardiac venous drainage and the cardiac lymphatics.
When we describe the heart in this chapter, and in subsequent chapters, our account will be based on the organ as viewed in its anatomical position.1 Where appropriate, the heart will be illustrated as it would be viewed by the surgeon during an operative procedure, irrespective of whether the pictures are taken in the operating room, or are photographs of autopsied hearts. When we show an illustration in non-surgical orientation, this will be clearly stated.
In the normal individual, the heart lies in the mediastinum, with two-thirds of its bulk to the left of the midline (Figure 1.1). The surgeon can approach the heart, and the great vessels, either laterally through the thoracic cavity, or directly through the mediastinum anteriorly. To make such approaches safely, knowledge is required of the salient anatomical features of the chest wall, and of the vessels and the nerves that course through the mediastinum (Figure 1.2).