Catherine Fitch, soprano; Maureen Volk, piano; Clark Ross, guitar

Catherine Fitch, soprano; Maureen Volk, piano; Clark Ross, guita

Compton scattering in strong magnetic fields: Spin-dependent influences at the cyclotron resonance

The quantum electrodynamical (QED) process of Compton scattering in strong magnetic fields is commonly invoked in atmospheric and inner magnetospheric models of x-ray and soft gamma-ray emission in high-field pulsars and magnetars. A major influence of the field is to introduce resonances at the cyclotron frequency and its harmonics, where the incoming photon accesses thresholds for the creation of virtual electrons or positrons in intermediate states with excited Landau levels. At these resonances, the effective cross section typically exceeds the classical Thomson value by over 2 orders of magnitude. Near and above the quantum critical magnetic field of 44.13 TeraGauss, relativistic corrections must be incorporated when computing this cross section. This paper presents formalism for the QED magnetic Compton differential cross section valid for both subcritical and supercritical fields, yet restricted to scattered photons that are below pair creation threshold. Calculations are developed for the particular case of photons initially propagating along the field, mathematically simple specializations that are germane to interactions involving relativistic electrons frequently found in neutron star magnetospheres. This exposition of relativistic, quantum, magnetic Compton cross sections treats electron spin dependence fully, since this is a critical feature for describing the finite decay lifetimes of the intermediate states. The formalism employs both the Johnson and Lippmann (JL) wave functions and the Sokolov and Ternov (ST) electron eigenfunctions of the magnetic Dirac equation. The ST states are formally correct for self-consistently treating spin-dependent effects that are so important in the resonances. Relatively compact analytic forms for the cross sections are presented that will prove useful for astrophysical modelers.Comment: 45 pages, 10 figures, accepted for publication in Phys. Rev.

Food Insecurity During Childhood: Understanding Persistence and Change Using Linked Current Population Survey Data

Our paper examines the prevalence and determinants of children’s transitions into and out of food insecurity since 2001. We use longitudinally linked data from the Food Security Supplements to the Current Population Surveys to estimate one-year transition probabilities of entry and exit from food insecurity. Our results indicate that child hunger is typically short-lived, but children experiencing very low food security frequently experience multiple consecutive years of food insecurity. We demonstrate large demographic and socioeconomic differences in rates of entry into very low food security and persistence in children\u27s food insecurity. Income and employment shocks are important predictors of child hunger transitions. Finally, we find that the Great Recession increased the likelihood that children entered into and persisted in food insecurity among children

Indigenous Cultural and Intellectual Property Protocol for Curriculum

The University of Sydney Business School is committed to embedding culturally competent practice in all aspects of our research, teaching and engagement. We will work to ensure that all staff, students and community members with whom we interact feel safe, respected and valued. As part of this commitment, the University of Sydney Business School Indigenous Cultural and Intellectual Protocol for Curriculum supports academic and professional staff in promoting culturally safe practices across our teaching programs. It is with great pride and respect for the knowledges and cultures of Aboriginal and Torres Strait Islander peoples that we invite you to learn from, explore, and embed this Protocol in your work. This Protocol has been co-designed with the aim of guiding, educating and directing Business School staff about the importance of cultural attribution and recognising the rights of Aboriginal and Torres Strait Islander peoples to their Indigenous Cultural and Intellectual Property. The Protocol guides educational practices that encourage self-representation of Aboriginal and Torres Strait Islander peoples and the process to establish and maintain strong relations with Aboriginal and Torres Strait Islander peoples and communities. We recognise that Aboriginal and Torres Strait Islander knowledge and perspectives have been historically excluded or misrepresented within Western education systems, and we are committed to promoting culturally responsive curriculum practices that recognise the richness and diversity of Aboriginal and Torres Strait Islander cultures and knowledge. The Protocol outlined in this document is intended to provide a framework for all staff in the Business School to engage in culturally responsive practices. It is envisaged that this work can help inform culturally responsive curriculum practices in your own curriculum design and development lifecycle. This Protocol provides a valuable resource for educators who seek to engage with Aboriginal and Torres Strait Islander peoples and communities, knowledge and culture in a respectful and meaningful way

Going beyond (electronic) patient-reported outcomes: harnessing the benefits of smart technology and ecological momentary assessment in cancer survivorship research

Rapid developments in digital mobile and sensor technology have facilitated the active and passive collection of detailed, personalized data in increasingly affordable ways. Researchers may be familiar with the daily diary, portable computers, or the pedometer for the collection of patientreported outcomes (PRO) in cancer survivorship research. Such methods, termed ecological momentary assessment (EMA), have evolved with technological advances, e.g., collecting data or providing interventions (ecological momentary intervention, EMI) via apps or devices such as smartphones. These smart technology-adapted sEMA/ sEMI methods are more widely used in affective disorders or addictive behavior research but are currently still under-utilized in cancer survivorship research. A recent scoping review on the use of active EMA among cancer survivors identified twelve articles published between 1993 and 2018. Most of the included studies in that review used portable computers. This commentary will discuss the utility of sEMA/sEMI in cancer survivorship research and call for action to advance this area of science

Development of an occupational advice intervention for patients undergoing lower limb arthroplasty (the OPAL study)

Background: There are an increasing number of patients of working age undergoing hip and knee replacements. Currently there is variation in the advice and support given about sickness absence, recovery to usual activities and return to work after these procedures. Earlier, sustainable, return to work improves the health of patients and benefits their employers and society. An intervention that encourages and supports early recovery to usual activities, including work, has the potential to reduce the health and socioeconomic burden of hip and knee replacements. Methods/design: A two-phase research programme delivered over 27 months will be used to develop and subsequently test the feasibility of an occupational advice intervention to facilitate return to work and usual activities in patients undergoing lower limb arthroplasty. The 2 phases will incorporate a six-stage intervention mapping process: Phase 1: Intervention mapping stages 1–3: 1 Needs assessment (including rapid evidence synthesis, prospective cohort analysis and structured stakeholder interviews) 2 Identification of intended outcomes and performance objectives 3 Selection of theory-based methods and practical strategies Phase 2: Intervention mapping stages 4–6: 4 Development of components and materials for the occupational advice intervention using a modified Delphi process 5 Adoption and implementation of the intervention 6 Evaluation and feasibility testing The study will be undertaken in four National Health Service (NHS) hospitals in the United Kingdom and two Higher Education Institution. Discussion: OPAL (Occupational advice for Patients undergoing Arthroplasty of the Lower limb) aims to develop an occupational advice intervention to support early recovery to usual activities including work, which is tailored to the requirements of patients undergoing hip and knee replacements. The developed intervention will then be assessed with a specific focus on evaluating its feasibility as a potential trial intervention to improve speed of recovery to usual activities including work

Microgeographic variation in body condition of three Mexican garter snakes in central Mexico

Background. Geographic variation in body size and condition can reveal differential local adaptation to resource availability or climatic factors. Body size and condition are related to fitness in garter snakes (Thamnophis), thus good body condition may increase survival, fecundity in females, and mating success in males. Phylogenetically related species in sympatry are predicted to exhibit similar body condition when they experience similar environmental conditions. We focused on interspecific and geographical variation in body size and condition in three sympatric Mexican garter snakes from the highlands of Central Mexico. Methods. We assessed SVL, mass, and body condition (obtained from Major axis linear regression of ln-transformed body mass on ln-transformed SVL) in adults and juveniles of both sexes of Thamnophis eques, T. melanogaster, and T. scalaris sampled at different locations and ranges from 3 11 years over a 20-year period. Results. We provide a heterogeneous pattern of sexual and ontogenic reproductive status variations of body size and condition among local populations. Each garter snake species shows locations with good and poor body condition; juvenile snakes show similar body condition between populations, adults show varying body condition between populations, and adults also show sex differences in body condition.Wediscuss variations in body condition as possibly related to the snakes' life cycle differences.Universidad Autónoma del Estado de México (Number 4047/2016SF)

Evolution of Symbiotic Bacteria in the Distal Human Intestine

The adult human intestine contains trillions of bacteria, representing hundreds of species and thousands of subspecies. Little is known about the selective pressures that have shaped and are shaping this community's component species, which are dominated by members of the Bacteroidetes and Firmicutes divisions. To examine how the intestinal environment affects microbial genome evolution, we have sequenced the genomes of two members of the normal distal human gut microbiota, Bacteroides vulgatus and Bacteroides distasonis, and by comparison with the few other sequenced gut and non-gut Bacteroidetes, analyzed their niche and habitat adaptations. The results show that lateral gene transfer, mobile elements, and gene amplification have played important roles in affecting the ability of gut-dwelling Bacteroidetes to vary their cell surface, sense their environment, and harvest nutrient resources present in the distal intestine. Our findings show that these processes have been a driving force in the adaptation of Bacteroidetes to the distal gut environment, and emphasize the importance of considering the evolution of humans from an additional perspective, namely the evolution of our microbiomes