The Crustal Dichotomy Boundary West of Tempe Terra: Speculation on Where it Lies Beneath Alba Patera Based on Mola Topography

MOLA gridded data based on profiles collected during the Aerobraking Hiatus and Science Phasing Operations suggest the crustal dichotomy boundary west of Tempe continues beneath Alba volcanics, at least to 105 W at about 50 N. A broad shelf-like region in the Alba units is continuous with a similar region of Tempe in which Hesperian volcanics overlie Noachian cratered terrain. Perspective views show significant changes in the sloping character of the flanks of Alba east and west of 105W, with much more continuous steep topography to the west. We suggest that Alba sits astride the ancient crustal dichotomy boundary, not adjacent to it, and that its eastern half lies on old cratered terrain. If true, this would significantly affect the estimate of Alba volcanics volumes, and might also explain some of the observed asymmetries in the structure and the distribution of faults associated with this immense feature

Identifying Young Brown Dwarfs Using Gravity-Sensitive Spectral Features

We report the initial results of the Brown Dwarf Spectroscopic Survey Gravity Project, to study gravity sensitive features as indicators of youth in brown dwarfs. Low-resolution (R~2000) J-band and optical (R~1000) observations using NIRSPEC and LRIS at the W.M. Keck Observatory reveal transitions of TiO, VO, K I, Na I, Cs I, Rb I, CaH, and FeH. By comparing these features in late-type giants and in old field dwarfs we show that they are sensitive to the gravity (g = GM/R^2) of the object. Using low-gravity spectral signatures as age indicators, we observed and analyzed J-band and optical spectra of two young brown dwarfs, G 196-3B (20-300 Myr) and KPNO Tau-4 (1-2 Myr), and two possible low mass brown dwarfs in the sigma Orionis cluster (3-7 Myr). We report the identification of the phi bands of TiO near 1.24 microns and the A-X band of VO near 1.18 microns together with extremely weak J-band lines of K I in KPNO-Tau4. This is the first detection of TiO and VO in the J-band in a sub-stellar mass object. The optical spectrum of KPNO-Tau4 exhibits weak K I and Na I lines, weak absorption by CaH, and strong VO bands, also signatures of a lower gravity atmosphere. G 196-3B shows absorption features in both wavelength regions like those of KPNO-Tau4 suggesting that its age and mass are at the lower end of published estimates. Whereas sigma Ori 51 appears to be consistent with a young sub-stellar object, sigma Ori 47 shows signatures of high gravity most closely resembling an old L1.5/L0, and can not be a member of the sigma Orionis cluster.Comment: 14 pages, 4 figures. To appear in the January 10, 2004 issue of the Astrophysical Journa

The NIRSPEC Brown Dwarf Spectroscopic Survey II: High-Resolution J-Band Spectra of M, L and T Dwarfs

We present a sequence of high resolution (R~20,000 or 15 km/s) infrared spectra of stars and brown dwarfs spanning spectral types M2.5 to T6. Observations of 16 objects were obtained using eight echelle orders to cover part of the J-band from 1.165-1.323 micron with NIRSPEC on the Keck II telescope. By comparing opacity plots and line lists, over 200 weak features in the J-band are identified with either FeH or H2O transitions. Absorption by FeH attains maximum strength in the mid-L dwarfs, while H2O absorption becomes systematically stronger towards later spectral types. Narrow resolved features broaden markedly after the M to L transition. Our high resolution spectra also reveal that the disappearance of neutral Al lines at the boundary between M and L dwarfs is remarkably abrupt, presumably because of the formation of grains. Neutral Fe lines can be traced to mid-L dwarfs before Fe is removed by condensation. The neutral potassium (K I) doublets that dominate the J-band have pressure broadened wings that continue to broaden from ~50 km/s (FWHM) at mid-M to ~500 km/s at mid-T. In contrast however, the measured pseudo-equivalent widths of these same lines reach a maximum in the mid-L dwarfs. The young L2 dwarf, G196-3B, exhibits narrow potassium lines without extensive pressure-broadened wings, indicative of a lower gravity atmosphere. Kelu-1AB, another L2, has exceptionally broad infrared lines, including FeH and H2O features, confirming its status as a rapid rotator. In contrast to other late T objects, the peculiar T6 dwarf 2MASS 0937+29 displays a complete absence of potassium even at high resolution, which may be a metallicity effect or a result of a cooler, higher-gravity atmosphere.Comment: 53 pages, 21 figures, data will be available at http://www.astro.ucla.edu/~mclean/BDSSarchive

The NIRSPEC Brown Dwarf Spectroscopic Survey. I. Low-Resolution Near-Infrared Spectra

We present the first results of a near-infrared (0.96-2.31 micron) spectroscopic survey of M, L, and T dwarfs obtained with NIRSPEC on the Keck II telescope. Our new survey has a resolving power of R = 2000 and is comprised of two major data sets: 53 J-band (1.14-1.36 micron) spectra covering all spectral types from M6 to T8 with at least two members in each spectral subclass (wherever possible), and 25 flux-calibrated spectra from 1.14 to 2.31 microns for most spectral classes between M6 and T8. Sixteen of these 25 objects have additional spectral coverage from 0.96-1.14 microns to provide overlap with optical spectra. Spectral flux ratio indexes for prominent molecular bands are derived and equivalent widths (EWs) for several atomic lines are measured. We find that a combination of four H2O and two CH4 band strengths can be used for spectral classification. Weak (EW~1-2 angstrom) atomic lines of Al I and Ca I disappear at the boundary between M and L types.Comment: 60 pages, 25 figures. To appear in the Astrophysical Journal Vol 596. Received 2003 March 31; accepted 2003 June 20. Web site at http://www.astro.ucla.edu/~mclean/BDSSarchiv

Parental decision making about safer sleep practices: A qualitative study of the perspectives of families with additional health and social care needs

\ua9 2024 Barrett et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Introduction Despite a decline in Sudden Unexpected Death in Infancy in the UK since 2004, inequalities have widened with higher rates among families from deprived backgrounds and those known to child protection services. Almost all cases involve parents who had engaged in unsafe sleeping practices despite awareness of safer sleeping advice. Objective To understand the perspectives surrounding safer sleep of families supported by statutory child protection agencies, and use behavior change theory to inform how approaches to providing safer sleep advice to these families may be modified. Participants and setting We interviewed 14 mothers, 2 fathers and one grandmother, who had recent contact with child protection services in northeast England. Methods In-depth, semi-structured interviews, with purposive sampling. The COM-B model (Capability, Opportunity, and Motivation) structured our analysis. Results Parents described how anxiety, sleep deprivation, settling infants, illness, and a desire to bond with infants influence their decision making about sleep. Parents valued credible, trusted sources and understanding how safer sleep practices protect infants. Responses to questions about \u27out of routine\u27 situations suggested social pressures surrounding routines and \u27good parenting\u27 may preclude parents from acknowledging risks and planning for these situations. Conclusion Open conversations tailored to the needs of families, focused upon understanding why and when parent(s) do or do not follow safer sleep guidance seem a promising way of promoting safer sleep practices. Safer sleep discussions with these families are likely to be best delivered as part of wider infant care by professionals who have an established and continuing trusting relationship with parents. While advice and information should be provided by any professional in contact with the family with the necessary expertise, sensitive conversations around sleeping practices, particularly co-sleeping, may be more easily facilitated by professionals where the statutory responsibility for safeguarding is less apparent

A Behaviour Change Analysis of Safer Sleep Interventions for Infants at Risk of Sudden and Unexpected Death

\ua9 2024 The Authors. Child Abuse Review published by Association of Child Protection Professionals and John Wiley & Sons Ltd.Rates of sudden unexpected death in infancy have been found to occur disproportionately amongst families living in the most deprived neighbourhoods. This suggests that standard safer sleep messaging may not be effective for this population and that research is required to identify ways of working that are better associated with behavioural change in parents with children at increased risk of SUDI. In this study, we aimed to explore the behavioural change components and mechanisms of action of safer sleep interventions for families with children at increased risk of SUDI. We conducted an analysis of the literature on safer sleep interventions using the COM-B model, Theoretical Domains Framework and Behavioural Change Technique Taxonomy. All interventions targeted parents\u27 capability; 15 interventions targeted parents\u27 opportunity; and six interventions targeted parents\u27 motivation to engage in safer sleep practices. Nineteen behavioural change techniques were identified. The focus of practitioners may need to shift from solely the delivery of safer sleep information towards working with parents to understand their capability, opportunity and, in particular, motivation to engage in safer sleep practices, identified as being a key driver of behaviour in this population

Innovative local authority public health interventions to support the mental health of children and young people

Purpose – Mental health champions (MHCs) and young health ambassadors (YHAs) are two innovative public health interventions. MHCs are practitioners who work in schools and other youth settings and aim to be the ‘‘go to’’ person for mental health in these settings. YHAs are a linked parallel network of young people, who champion mental health and advocate for youth involvement, which was co-produced with young people across all stages of development implementation. This paper aims to identify the potential benefits, barriers and facilitators of these interventions.Design/methodology/approach – Semi-structured qualitative interviews (n 1⁄4 19) were undertaken with a purposive sample of n 1⁄4 13 MHCs, and n 1⁄4 6 YHAs, between June 2021 and March 2022. Interviews were audio-recorded, transcribed, anonymised and then analysed following a thematic approach. Ethical approval was granted by Newcastle University’s Faculty of Medical Sciences Ethics Committee. Findings – The findings are organised under five key themes: motivating factors and rewards for MHCs and YHAs; outcomes for children and young people (CYP) and others; impact on youth settings and culture; facilitators of successful implementation; and implementation challenges and opportunities.Practical implications – These findings are intended to be of relevance to practice and policy, particularly to those exploring the design, commissioning or implementation of similar novel and low-cost interventions, which aim to improve mental health outcomes for CYP, within the context of youth settings.Originality/value – The interventions reported on in the present paper are novel and innovative. Little research has previously been undertaken to explore similar approaches, and the individual experiences of those involved in the delivery of these types of interventions

Medieval Iceland, Greenland, and the New Human Condition: A case study in integrated environmental humanities

This paper contributes to recent studies exploring the longue durée of human impacts on island landscapes, the impacts of climate and other environmental changes on human communities, and the interaction of human societies and their environments at different spatial and temporal scales. In particular, the paper addresses Iceland during the medieval period (with a secondary, comparative focus on Norse Greenland) and discusses episodes where environmental and climatic changes have appeared to cross key thresholds for agricultural productivity. The paper draws upon international, interdisciplinary research in the North Atlantic region led by the North Atlantic Biocultural Organization (NABO) and the Nordic Network for Interdisciplinary Environmental Studies (NIES) in the Circumpolar Networks program of the Integrated History and Future of People on Earth (IHOPE). By interlinking analyses of historically grounded literature with archaeological studies and environmental science, valuable new perspectives can emerge on how these past societies may have understood and coped with such impacts. As climate and other environmental changes do not operate in isolation, vulnerabilities created by socioeconomic factors also beg consideration. The paper illustrates the benefits of an integrated environmental-studies approach that draws on data, methodologies and analytical tools of environmental humanities, social sciences, and geosciences to better understand long-term human ecodynamics and changing human-landscape-environment interactions through time. One key goal is to apply previously unused data and concerted expertise to illuminate human responses to past changes; a secondary aim is to consider how lessons derived from these cases may be applicable to environmental threats and socioecological risks in the future, especially as understood in light of the New Human Condition, the concept transposed from Hannah Arendt's influential framing of the human condition that is foregrounded in the present special issue. This conception admits human agency's role in altering the conditions for life on earth, in large measure negatively, while acknowledging the potential of this self-same agency, if effectively harnessed and properly directed, to sustain essential planetary conditions through a salutary transformation of human perception, understanding and remedial action. The paper concludes that more long-term historical analyses of cultures and environments need to be undertaken at various scales. Past cases do not offer perfect analogues for the future, but they can contribute to a better understanding of how resilience and vulnerability occur, as well as how they may be compromised or mitigated

Effective Field Theory Dimensional Regularization

A Lorentz-covariant regularization scheme for effective field theories with an arbitrary number of propagating heavy and light particles is given. This regularization scheme leaves the low-energy analytic structure of Greens functions intact and preserves all the symmetries of the underlying Lagrangian. The power divergences of regularized loop integrals are controlled by the low-energy kinematic variables. Simple diagrammatic rules are derived for the regularization of arbitrary one-loop graphs and the generalization to higher loops is discussed.Comment: 22 pages, 11 figures and 1 tabl