4,959 research outputs found

    Near-Infrared Photometric Survey of Herbig Ae/Be Candidate Stars

    Full text link
    We report near-infrared photometric measurements of 35 Herbig Ae/Be candidate stars obtained with direct imaging and aperture photometry. Observations were made through the broadband J, H, and K' filters, with each source imaged in at least one of the wavebands. We achieved subarcsecond angular resolution for all observations, providing us with the opportunity to search for close binary candidates and extended structure. The imaging revealed five newly identified binary candidates and one previously resolved T Tauri binary among the target sources with separations of <~2.5". Separate photometry is provided for each of the binary candidate stars. We detect one extended source that has been identified as a protoplanetary nebula. Comparing our magnitudes to past measurements yields significant differences for some sources, possibly indicating photometric variability. H-band finding charts for all of our sources are provided to aid follow-up high-resolution imaging.Comment: 22 pages, 1 figure, accepted for publication in A

    Distribution of slow and fast rotators in the Fornax cluster

    No full text
    We present integral field spectroscopy of 10 early-type galaxies in the nearby, low-mass, Fornax cluster, from which we derive spatially resolved stellar kinematics. Based on the morphologies of their stellar velocity maps we classify 2/10 galaxies as slow rotators, with the remaining eight galaxies fast rotators. Supplementing our integral field observations with morphological and kinematic data from the literature, we analyse the ‘kinematic’ type of all 30 galaxies in the Fornax cluster brighter than MK = −21.5 mag (M* ∌ 6 × 109 M⊙). Our sample's slow rotator fraction within one virial radius is 7+4−6 per cent. 13+8−6 per cent of the early-type galaxies are slow rotators, consistent with the observed fraction in other galaxy aggregates. The fraction of slow rotators in Fornax varies with cluster-centric radius, rising to 16+11−8 per cent of all kinematic types within the central 0.2 virial radii, from 0 per cent in the cluster outskirts. We find that, even in mass-matched samples of slow and fast rotators, slow rotators are found preferentially at higher projected environmental density than fast rotators. This demonstrates that dynamical friction alone cannot be responsible for the differing distributions of slow and fast rotators. For dynamical friction to play a significant role, slow rotators must reside in higher mass sub-haloes than fast rotators and/or form in the centres of groups before being accreted on to the cluster

    On the distribution of galaxy ellipticity in clusters

    Get PDF
    open4We study the distribution of projected ellipticity n(Δ) for galaxies in a sample of 20 rich (Richness ≄ 2) nearby (z 0.4), therefore it is not a consequence of the increasing fraction of round slow rotator galaxies near cluster centers. Furthermore, the Δ-R relation persists for just smooth flattened galaxies and for galaxies with deVaucouleurs-like light profiles, suggesting that the variation of the spiral fractionwith radius is not the underlying cause of the trend. We interpret our findings in light of the classification of early type galaxies (ETGs) as fast and slow rotators. We conclude that the observed trend of decreasing Δ towards the centres of clusters is evidence for physical effects in clusters causing fast rotator ETGs to have a lower average intrinsic ellipticity near the centres of rich clusters.openD'Eugenio F.; Houghton R.C.W.; Davies R.L.; Dalla Bonta' E.D'Eugenio, F.; Houghton, R. C. W.; Davies, R. L.; Dalla Bonta', E

    The Effects of COVID-19 Social Restrictions and Subsequent Informal Support Limitations on Intimate Partner Violence: An Opinion Piece

    Get PDF
    Two years since the Coronavirus Disease-2019 (COVID-19) was declared a worldwide pandemic, there have been more than 460 million people infected and more than 6 million deaths (1). As the highly infectious Omicron strain continues to spread worldwide, case numbers are again trending upwards in many countries. Daily, there are on average, over a million new cases and over 5,000 deaths being recorded [as of 15/03/2022; (1)]. Similar to previous times of crisis (e.g., natural disasters), an increase in violence has been observed (2), and this has been disproportionately seen in intimate partner violence against women [IPVAW; (3, 4)]. Whilst it is noted that men can be victims of interpersonal violence, the majority of this violence is perpetrated against female intimate partners (5). Additionally, while IPVAW occurs among all social groups, ethnic minorities and migrant women are more vulnerable (6). IPVAW is categorized by acts of a physical, sexual, and/or psychological nature committed by either a current or former partner (7). IPVAW is underpinned by a perpetrator's use of coercive control, which is the patterned and repetitive use of various violent behaviors to frighten or punish the survivor (8). IPVAW can have long term negative consequences, with survivors experiencing reduced quality of life outcomes (9). This opinion article considers what risk factors COVID-19 and its restrictions have exacerbated, and how restrictions have reduced the efficacy of informal supporters

    Face-to-Face Compared With Online Collected Accounts of Health and Illness Experiences: A Scoping Review.

    Get PDF
    Advocates of online alternatives to face-to-face interviewing suggest online approaches save money and time, whereas others have raised concerns about the quality and content of the resulting data. These issues affect researchers designing and costing their studies and application reviewers and research funders. We conducted a scoping review of English language articles describing the range of online alternative approaches. Furthermore, we systematically identified studies directly comparing online alternatives with face-to-face approaches. Synthesis of these 11 articles (565 participants) suggests that online alternatives should not be viewed as a straightforward replacement for face-to-face, a particularly important finding given the rapid communication changes occurring in the COVID-19 pandemic. When applied with consideration of the evolving evidence on their strengths and weaknesses, online methods may increase the likelihood of obtaining the desired sample, but responses are shorter, less contextual information is obtained, and relational satisfaction and consensus development are lower

    Development and validation of the Informal Supporter Readiness Inventory (ISRI)

    Get PDF
    Objective This article outlines the development and validation of the Informal Supporter Readiness Inventory (ISRI), based on the model developed by the present authors in (Davies, 2023). This scale assesses the readiness of informal supporters to intervene or provide support in situations of intimate partner violence (IPV). Methods The research followed a three-phased procedure of item development, scale development, and scale evaluation; adhering to best practice guidelines for psychometric development and validation. This process provided empirical substantiation for the domains of the Model of Informal Supporter Readiness (Davies, 2023). Results The 57-item ISRI incorporates four primary factors: normative, individual, goodman-emotional, and situational-assessment. These factors demonstrated robust internal consistency and factor structures. Additionally, the ISRI evidenced strong test-retest reliability, and both convergent and divergent validity. Although aligning closely with the Model of Informal Supporter Readiness, the scale revealed a nuanced bifurcation of situational factors into situational-emotional and situational-assessment. Discussion The ISRI offers an important advancement in IPV research by highlighting the multifaceted nature of informal supporter intervention. The findings have several implications, from tailoring individualised supportive interventions to strengthening support networks and empowering survivors. The present study’s findings underscore the potential of adopting a social network-oriented approach to interventions in IPV scenarios. Applications for research and practice are discussed

    Applying an extended Theory of Planned Behaviour to predict breakfast consumption in adolescents

    Get PDF
    Background/Objectives: Breakfast skipping increases during adolescence and is associated with lower levels of physical activity and weight gain. Theory-based interventions promoting breakfast consumption in adolescents report mixed findings, potentially due to limited research identifying which determinants to target. This study aimed to: (i) utilise the Theory of Planned Behaviour (TPB) to identify the relative contribution of attitudes (affective, cognitive and behavioural) to predict intention to eat breakfast and breakfast consumption in adolescents; (ii) determine whether demographic factors moderates the relationship between TPB variables, intention and behaviour. Subjects/Methods: Questionnaires were completed by 434 students (mean 14 ± 0.9 years) measuring breakfast consumption (0-2, 3-6 or 7 days), physical activity levels and TPB measures. Data were analysed by breakfast frequency and demographics using hierarchical and multinomial regression analyses. Results: Breakfast was consumed every day by 57% of students with boys more likely to eat a regular breakfast, report higher activity levels and more positive attitudes towards breakfast than girls (p<.001). The TPB predicted 58% of the variation in intentions. Overall, the model was predictive of breakfast behaviours (p<.001), but the relative contribution of TPB constructs varied depending on breakfast frequency. Interactions between gender and intentions were significant when comparing 0-2 and 3-6 day breakfast eaters only highlighting a stronger intention-behaviour relationship for girls. Conclusions: Findings confirm that the TPB is a successful model for predicting breakfast intentions and behaviours in adolescents. The potential for a direct effect of attitudes on behaviours should be considered in the implementation and design of breakfast interventions

    Ion-Molecule Interactions Enable Unexpected Phase Transitions in Organic-Inorganic Aerosol

    Get PDF
    Atmospheric aerosol particles are commonly complex, aqueous organic-inorganic mixtures, and accurately predicting the properties of these particles is essential for air quality and climate projections. The prevailing assumption is that aqueous organic-inorganic aerosols exist predominately with liquid properties and that the hygroscopic inorganic fraction lowers aerosol viscosity relative to the organic fraction alone. Here, in contrast to those assumptions, we demonstrate that increasing inorganic fraction can increase aerosol viscosity (relative to predictions) and enable a humidity-dependent gel phase transition through cooperative ion-molecule interactions that give rise to long-range networks of atmospherically relevant low-mass oxygenated organic molecules (180 to 310 Da) and divalent inorganic ions. This supramolecular, ion-molecule effect can drastically influence the phase and physical properties of organic-inorganic aerosol and suggests that aerosol may be (semi)solid under more conditions than currently predicted. These observations, thus, have implications for air quality and climate that are not fully represented in atmospheric models

    Effect of telehealth-integrated antenatal care on pregnancy outcomes in Australia : an interrupted time-series analysis

    Get PDF
    Funding Information: We thank all the staff involved in the implementation and provision of telehealth-integrated antenatal care and the women receiving care who adapted to the many changes during the pandemic.Peer reviewe

    The effects of moderate prenatal alcohol exposure on the organization of exploratory behavior by adult female rats

    Get PDF
    A large body of research has indicated that moderate Prenatal Alcohol Exposure (PAE - 60 mg/dl peak BAC) can produce impairments on cognitive processes, such as spatial learning and memory. The neurobiological basis of these impairments is poorly understood but is frequently linked to alterations in hippocampal functioning. Although the hippocampus has a central role in learning and memory, damage to the hippocampus can also produce impairments in locomotor and exploratory behaviors by rodents (reviewed in Thompson et al., 2018). Rodent exploratory behavior is organized around home bases, which serves as central points of attraction from which rats and mice organize their exploratory trips into the remaining environment. We are unaware of studies investigating the relationship between moderate prenatal alcohol exposure and exploratory behavior. Thus, in the present study, we tested adult female rats in two experiments where they were allowed to freely explore a circular open field for ~30min. Here, we report that, with respect to home base behavior, exploratory movements were largely intact in rats exposed to alcohol prenatally. Specifically, animals rapidly established home bases within 5min of the beginning of testing and the bases were established in one or two locations in the environment. They made exploratory trips away and back to the home base and made several stops at this location along with bouts of grooming behavior. The results are discussed with respect to theories of hippocampal function and the impact of moderate prenatal alcohol on spatial behavior
    • 

    corecore