Structure of vortices in rotating Bose-Einstein condensates

We calculate the structure of individual vortices in rotating Bose-Einstein condensates in a transverse harmonic trap. Making a Wigner-Seitz approximation for the unit cell of the vortex lattice, we derive the Gross-Pitaevskii equation for the condensate wave function in each cell of the lattice, including effects of varying coarse grained density. We calculate the Abrikosov parameter, the fractional core area, and the energy of individual cells.Comment: 10 pages, 9 figures, published versio

Tracking system study

A digital computer program was generated which mathematically describes an optimal estimator-controller technique as applied to the control of antenna tracking systems used by NASA. Simulation studies utilizing this program were conducted using the IBM 360/91 computer. The basic ideas of applying optimal estimator-controller techniques to antenna tracking systems are discussed. A survey of existing tracking methods is given along with shortcomings and inherent errors. It is explained how these errors can be considerably reduced if optimal estimation and control are used. The modified programs generated in this project are described and the simulation results are summarized. The new algorithms for direct synthesis and stabilization of the systems including nonlinearities, are presented

Reductions in the dietary niche of southern sea otters (Enhydra lutris nereis) from the Holocene to the Anthropocene.

The sea otter (Enhydra lutris) is a marine mammal hunted to near extinction during the 1800s. Despite their well-known modern importance as a keystone species, we know little about historical sea otter ecology. Here, we characterize the ecological niche of ancient southern sea otters (E. lutris nereis) using δ13C analysis and δ15N analysis of bones recovered from archaeological sites spanning ~7,000 to 350 years before present (N = 112 individuals) at five regions along the coast of California. These data are compared with previously published data on modern animals (N = 165) and potential modern prey items. In addition, we analyze the δ15N of individual amino acids for 23 individuals to test for differences in sea otter trophic ecology through time. After correcting for tissue-specific and temporal isotopic effects, we employ nonparametric statistics and Bayesian niche models to quantify differences among ancient and modern animals. We find ancient otters occupied a larger isotopic niche than nearly all modern localities; likely reflecting broader habitat and prey use in prefur trade populations. In addition, ancient sea otters at the most southerly sites occupied an isotopic niche that was more than twice as large as ancient otters from northerly regions. This likely reflects greater invertebrate prey diversity in southern California relative to northern California. Thus, we suggest the potential dietary niche of sea otters in southern California could be larger than in central and northern California. At two sites, Año Nuevo and Monterey Bay, ancient otters had significantly higher δ15N values than modern populations. Amino acid δ15N data indicated this resulted from shifting baseline isotope values, rather than a change in sea otter trophic ecology. Our results help in better understanding the contemporary ecological role of sea otters and exemplify the strength of combing zooarchaeological and biological information to provide baseline data for conservation efforts

Preparation for Full Time Employment: A Capstone Experience for Students in Leadership Programs

This practice paper describes the development and implementation of a senior capstone course for communication and leadership development for undergraduate students. The resulting course is a unique combination of experiential skill development and career preparation. The success of this course provides students with an important and meaningful culmination of their undergraduate experiences

Trace-element and physical response to melt percolation in Summit (Greenland) snow

Surface melt on a glacier can perturb the glaciochemical record beyond the natural variability. While the centre of the Greenland ice sheet is usually devoid of surface melt, many high- Arctic and alpine ice cores document frequent summertime melt events. Current hypotheses interpreting melt-affected ice-core chemistry rely on preferential elution of certain major ions. However, the precise nature of chemistry alteration is unknown because it is difficult to distinguish natural variability from melt effects in a perennially melt-affected site. We use eight trace-element snow chemistry records recovered from Summit, Greenland, to study spatial variability and melt effects on insoluble trace chemistry and physical stratigraphy due to artificially introduced meltwater. Differences between non-melt and melt-affected chemistry were significantly greater than the spatial variability in chemistry represented by nearest-neighbour pairs. Melt-perturbed trace elements, particularly rare earth elements, retained their seasonal stratigraphies, suggesting that trace elements may serve as robust chemical indicators for annual layers even in melt-affected study areas. Results suggest trace-element transport via meltwater percolation will deposit eluted material down-pit in refrozen areas below the nearest-surface chemistry peak. In our experiments, snow chemistry analyses are more sensitive to melt perturbations than density changes or unprocessed near-infrared digital imagery

Preparation for Full Time Employment: A Capstone Experience for Students in Leadership Programs

This practice paper describes the development and implementation of a senior capstone course for communication and leadership development for undergraduate students. The resulting course is a unique combination of experiential skill development and career preparation. The success of this course provides students with an important and meaningful culmination of their undergraduate experiences

A mixed methods systematic review on the effects of arts interventions for children and young people at-risk of offending, or who have offended on behavioural, psychosocial, cognitive and offending outcomes: A systematic review

Background Young people who enter the justice system experience complex health and social needs, and offending behaviour is increasingly recognised as a public health problem. Arts interventions can be used with the aim of preventing or reducing offending or reoffending. Objectives 1. To evaluate evidence on the effectiveness and impact of arts interventions on keeping children and young people safe from involvement in violence and crime. 2. To explore factors impacting the implementation of arts interventions, and barriers and facilitators to participation and achievement of intended outcomes. 3. To develop a logic model of the processes by which arts interventions might work in preventing offending behaviours. Search Methods We searched AMED, Academic Search Complete; APA PsycInfo; CINAHL Plus; ERIC; SocIndex; SportDiscus, Medline, CENTRAL, Web of Science, Scopus, PTSDPubs and Performing Arts Periodicals Database, Sage, the US National Criminal Justice Reference Service, the Global Policing and British Library EThOS databases, and the National Police Library from inception to January 2023 without language restrictions. Selection Criteria We included randomised and non-randomised controlled trials and quasi-experimental study designs. We included qualitative studies conducted alongside intervention trials investigating experiences and perceptions of participants, and offering insight into the barriers and facilitators to delivering and receiving arts interventions. We included qualitative and mixed methods studies focused on delivery of arts interventions. We included studies from any global setting. We included studies with CYP (8–25 years) who were identified as at-risk of offending behaviour (secondary populations) or already in the criminal justice system (tertiary populations). We included studies of interventions involving arts participation as an intervention on its own or alongside other interventions. Primary outcomes were: (i) offending behaviour and (ii) anti-pro-social behaviours. Secondary outcomes were: participation/attendance at arts interventions, educational attainment, school attendance and engagement and exclusions, workplace engagement, wellbeing, costs and associated economic outcomes and adverse events. Data Collection and Analysis We included 43 studies (3 quantitative, 38 qualitative and 2 mixed methods). We used standard methodological procedures expected by The Campbell Collaboration. We used GRADE and GRADE CERQual to assess the certainty of and confidence in the evidence for quantitative and qualitative data respectively. Main Results We found insufficient evidence from quantitative studies to support or refute the effectiveness of arts interventions for CYP at-risk of or who have offended for any outcome. Qualitative evidence suggested that arts interventions may lead to positive emotions, the development of a sense of self, successful engagement in creative practices, and development of positive personal relationships. Arts interventions may need accessible and flexible delivery and are likely to be engaging if they have support from staff, family and community members, are delivered by professional artists, involve culturally relevant activity, a youth focus, regularity and a sustainable strategy. We found limited evidence that a lack of advocacy, low funding, insufficient wider support from key personnel in adjacent services could act as barriers to success. Methodological limitations resulted in a judgement of very low confidence in these findings. Authors' Conclusions We found insufficient evidence from quantitative studies to support or refute the effectiveness of arts interventions for CYP at-risk of offending or who have offended for any outcome. We report very low confidence about the evidence for understanding the processes influencing the successful design and delivery of arts interventions in this population of CYP and their impact on behavioural, psychosocial, cognitive and offending outcomes.Brunel University London Information Services, UK | Youth Endowment Foundation, UK | Arts Council England, U

Origin and recent expansion of an endogenous gammaretroviral lineage in domestic and wild canids

Abstract Background Vertebrate genomes contain a record of retroviruses that invaded the germlines of ancestral hosts and are passed to offspring as endogenous retroviruses (ERVs). ERVs can impact host function since they contain the necessary sequences for expression within the host. Dogs are an important system for the study of disease and evolution, yet no substantiated reports of infectious retroviruses in dogs exist. Here, we utilized Illumina whole genome sequence data to assess the origin and evolution of a recently active gammaretroviral lineage in domestic and wild canids. Results We identified numerous recently integrated loci of a canid-specific ERV-Fc sublineage within Canis, including 58 insertions that were absent from the reference assembly. Insertions were found throughout the dog genome including within and near gene models. By comparison of orthologous occupied sites, we characterized element prevalence across 332 genomes including all nine extant canid species, revealing evolutionary patterns of ERV-Fc segregation among species as well as subpopulations. Conclusions Sequence analysis revealed common disruptive mutations, suggesting a predominant form of ERV-Fc spread by trans complementation of defective proviruses. ERV-Fc activity included multiple circulating variants that infected canid ancestors from the last 20 million to within 1.6 million years, with recent bursts of germline invasion in the sublineage leading to wolves and dogs.https://deepblue.lib.umich.edu/bitstream/2027.42/148209/1/12977_2019_Article_468.pd