The Formation of Galaxy Disks

We present a new set of multi-million particle SPH simulations of the formation of disk dominated galaxies in a cosmological context. Some of these galaxies are higher resolution versions of the models already described in Governato et al (2007). To correctly compare simulations with observations we create artificial images of our simulations and from them measure photometric Bulge to Disk (B/D) ratios and disk scale lengths. We show how feedback and high force and mass resolution are necessary ingredients to form galaxies that have flatter rotation curves, larger I band disk scale lengths and smaller B/D ratios. A new simulated disk galaxy has an I-band disk scale length of 9.2 kpc and a B/D flux ratio of 0.64 (face on, dust reddened).Comment: To appear in proceedings of "Formation and Evolution of Galaxy Disks", Rome, October 2007, Eds. J.G. Funes, S.J. and E.M. Corsini. Bigger figures than in printed versio

Critiquing the "National Standards for School-based Initial Teacher Training Mentors" in England: what lessons can be learned from inter-professional comparison?

Purpose – In 2016, the National Standards for School-based Initial Teacher Training (ITT) Mentors were published in England. This article seeks to critique these standards through a comparison of how others have framed and defined the role of the mentor, drawing on equivalent standards already published in nursing (2008) and social work (2012). Methodology – An analysis of three sets of professional standards was conducted by adapting the ‘constant comparison’ approach in which the researchers sought to combine a form of inductive coding with comparison across the texts. This enabled the identification of a number of common themes and omissions across the three sets of standards. Findings –The analysis revealed the ITT mentor standards provide a comparatively limited account of the role of the mentor, particularly in relation to the process of assessment, the power dynamics between mentors and student teachers, and the school as an institutional site for professional learning. Originality – The study’s originality lies in the inter-professional comparative analysis, which revealed a number of potentially contentious issues not immediately apparent from a close textual analysis of the ITT mentor standards

Technological needs of advanced Earth-observation spacecraft

An outline of the type of Earth observations needed is presented. The characteristics of a 120 meter by 60 meter microwave radiometer are discussed along with those of supplementary instruments

An NCAA Football Bowl Subdivision Production Function

Each year pundits across the NCAA football landscape debate the validity of various NCAA football teams’ relative worthiness to play for the national championship. Given this debate seems to revolve around which team is the best in terms of total team production, I have developed and statistically estimated a complex invasion NCAA football bowl subdivision production function measuring NCAA football team productivity covering the 2008 to 2017 seasons. The model estimates both points scored and points surrendered for each team during this time period and then is combined to determine each team’s overall productivity. Finally, as an application of the complex invasion college football production function model, I have ranked the overall productivity of the NCAA football bowl subdivision teams for the 2017 season to find the most productive team. The model concludes that the University of Alabama was the most productive team for the 2017 season

Characteristics of successful interventions to reduce turnover and increase retention of early career nurses: a systematic review

Background nurse shortages have been identified as central to workforce issues in healthcare systems globally and although interventions to increase the nursing workforce have been implemented, nurses leaving their roles, particularly in the first year after qualification, present a significant barrier to building the nurse workforce. Objective to evaluate the characteristics of successful interventions to promote retention and reduce turnover of early career nurses. Design this is a systematic review Data sources Online databases including Academic Search Complete, Medline, Health Policy reference Centre, EMBASE, Psychinfo, CINAHL and the Cochran Library were searched to identify relevant publications in English published between 2001 and April 2018. Studies included evaluated an intervention to increase retention or reduce turnover and used turnover or retention figures as a measure. Review methods The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies were quality-assessed using the Joanna Briggs Institute Critical Appraisal tools for Quasi Experimental and Randomised Controlled Trials. Retention/turnover data were used to guide the comparison between studies and appropriate measures of central tendency and dispersion were calculated and presented, based on the normality of the data. Results A total of 11, 656 papers were identified, of which 53 were eligible studies. A wide variety of interventions and components within those interventions were identified to improve nurse retention. Promising interventions appear to be either internship/residency programmes or orientation/transition to practice programmes, lasting between 27-52 weeks, with a teaching and preceptor and mentor component. Conclusions Methodological issues impacted on the extent to which conclusions could be drawn, even though a large number of studies were identified. Future research should focus on standardising the reporting of interventions and outcome measures used to evaluate these interventions and carrying out further research with rigorous methodology. Clinical practice areas are recommended to assess their current interventions against the identified criteria to guide development of their effectiveness. Evaluations of cost-effectiveness are considered an important next step to maximise return on investment

Aspects of Distribution, Abundance, Habitat, and Life History of the Caddo Madtom (\u3ci\u3eNoturus taylori\u3c/i\u3e), a Narrow Endemic of the Ouachita Highlands

The Caddo Madtom, Noturus taylori, is a small catfish endemic to the Ouachita Mountain ecoregion in Arkansas, with habitat altered by land use practices and reservoir dams. We examined aspects of distribution, abundance, habitat, and life history of N. taylori during seasonal sampling from winter 2016 through fall 2017. Our sampling data were concordant with previous studies that suggested N. taylori is more widespread and has higher catch per unit effort in the Caddo River drainage when compared to the upper Ouachita River drainage. We did not detect N. taylori in the Little Missouri River drainage, where it is presumed extirpated. A total of 370 individuals ranging from 14–76 mm (mean = 45.1 mm) standard length (SL) were collected during seasonal samples. Length-frequency analyses estimated a maximum age of 3 years for N. taylori, and we identified three discernable age classes with the emergence of young-of-year (age 0 cohort) in summer: age 0 (up to ~40 mm SL); age 1 (~41-60 mm SL); and age 2+ (\u3e60 mm SL). Sites where N. taylori was captured had an average depth of 20.6 cm, an average base velocity of 0.18 m/sec, and were dominated primarily by a mix of gravel, pebble, and cobble. Despite the relatively higher abundances of N. taylori in the Caddo River, we recommend that long-term, periodic monitoring of N. taylori would be an important conservation tool to assess potential future changes in distribution, habitat, occurrence, and abundance. Future studies that implement occupancy and habitat suitability modeling are needed to better understand suitable and preferred habitat of N. taylori

Properties of simulated Milky Way-mass galaxies in loose group and field environments

We test the validity of comparing simulated field disk galaxies with the empirical properties of systems situated within environments more comparable to loose groups, including the Milky Way's Local Group. Cosmological simulations of Milky Way-mass galaxies have been realised in two different environment samples: in the field and in environments with similar properties to the Local Group. Apart from the environments of the galaxies, the samples are kept as homogeneous as possible with equivalent ranges in last major merger time, halo mass and halo spin. Comparison of these two samples allow for systematic differences in the simulations to be identified. Metallicity gradients, disk scale lengths, colours, magnitudes and age-velocity dispersion relations are studied for each galaxy in the suite and the strength of the link between these and environment of the galaxies is studied. The bulge-to-disk ratio of the galaxies show that these galaxies are less spheroid dominated than many other simulated galaxies in literature with the majority of both samples being disk dominated. We find that secular evolution and mergers dominate the spread of morphologies and metallicity gradients with no visible differences between the two environment samples. In contrast with this consistency in the two samples there is tentative evidence for a systematic difference in the velocity dispersion-age relations of galaxies in the different environments. Loose group galaxies appear to have more discrete steps in their velocity dispersion-age relations. We conclude that at the current resolution of cosmological galaxy simulations field environment galaxies are sufficiently similar to those in loose groups to be acceptable proxies for comparison with the Milky Way provided that a similar assembly history is considered.Comment: 16 pages, 11 figures, abstract abridged for arXiv. Accepted for publication in Astronomy & Astrophysic

Empowering Energy Justice

The U.S. is experiencing unprecedented movement away from coal and, to a lesser degree, oil. Burdened low-income communities and people of color could experience health benefits from reductions in air and water pollution, yet these same groups could suffer harm if transitions lack broad public input or if policies prioritize elite or corporate interests. This paper highlights how U.S. energy transitions build from, and contribute to, environmental injustices. Energy justice requires not only ending disproportionate harm, it also entails involvement in the design of solutions and fair distribution of benefits, such as green jobs and clean air. To what extent does the confluence of state, civic, and market processes assure “just” transitions to clean, low-carbon energy production involving equitable distribution of costs, benefits, and decision-making power? To explore this question we assess trends with (1) fossil fuel divestment; (2) carbon taxes and social cost of carbon measurements; (3) cap-and-trade; (4) renewable energy; and (5) energy efficiency. Current research demonstrates opportunities and pitfalls in each area with mixed or partial energy justice consequences, leading to our call for greater attention to the specifics of distributive justice, procedural justice, and recognition justice in research, policy, and action. Illustrative energy transition case studies suggest the feasibility and benefit of empowering approaches, but also indicate there can be conflict between “green” and “just”, as evident though stark inequities in clean energy initiatives. To identify positive pathways forward, we compile priorities for an energy justice research agenda based on interactive and participatory practices aligning advocacy, activism, and academics