UNLV Jazz Ensemble II and III

Program listing performers and works performe

Civil Procedure: Restriction on the Trial Court\u27s Discretion in Ruling on Rule 55(c) and 60(b) Motions to Vacate Default Entries and Judgments

United Coin Meter Co. v. Seaboard Coastline R.R., 705 F.2d 839 (6th Cir. 1983)

Flux-Limited Diffusion for Multiple Scattering in Participating Media

For the rendering of multiple scattering effects in participating media, methods based on the diffusion approximation are an extremely efficient alternative to Monte Carlo path tracing. However, in sufficiently transparent regions, classical diffusion approximation suffers from non-physical radiative fluxes which leads to a poor match to correct light transport. In particular, this prevents the application of classical diffusion approximation to heterogeneous media, where opaque material is embedded within transparent regions. To address this limitation, we introduce flux-limited diffusion, a technique from the astrophysics domain. This method provides a better approximation to light transport than classical diffusion approximation, particularly when applied to heterogeneous media, and hence broadens the applicability of diffusion-based techniques. We provide an algorithm for flux-limited diffusion, which is validated using the transport theory for a point light source in an infinite homogeneous medium. We further demonstrate that our implementation of flux-limited diffusion produces more accurate renderings of multiple scattering in various heterogeneous datasets than classical diffusion approximation, by comparing both methods to ground truth renderings obtained via volumetric path tracing.Comment: Accepted in Computer Graphics Foru

Imaging the Haro 6-10 Infrared Companion

We present an infrared imaging study of the low-mass pre-main-sequence binary system Haro 6-10. This system is one of a handful in which the optically visible primary has the characteristics of a normal T Tauri star, while the secondary is a so-called "infrared companion" (IRC), a strongly extincted object that emits most of its luminosity in the infrared. A speckle holographic technique was used to produce nearly diffraction-limited images on three nights over a 1 yr period starting in late 1997. The images show that the IRC is obscured and surrounded by a compact, irregular, and variable nebula. This structure is in striking contrast to the well-ordered edge-on disk associated with HK Tauri B, the extincted companion to another T Tauri star of similar age. A new, resolved intensity peak was found 0".4 southwest of the IRC. We suggest that it may represent light scattered by a clump of dusty material illuminated by starlight escaping along an outflow-carved cavity in the IRC envelope. The primary star became fainter and the companion became more extended during the observing period

A New Brown Dwarf Desert? A Scarcity of Wide Ultracool Binaries

We present the results of a deep-imaging search for wide companions to low-mass stars and brown dwarfs using NSFCam on IRTF. We searched a sample of 132 M7-L8 dwarfs to magnitude limits of $J \sim 20.5$ and $K \sim 18.5$, corresponding to secondary-primary mass ratios of $\sim 0.5$. No companions were found with separations between 2{\arcsec} to 31{\arcsec} ($\sim$40 AU to $\sim$1000 AU). This null result implies a wide companion frequency below 2.3% at the 95% confidence level within the sensitivity limits of the survey. Preliminary modeling efforts indicate that we could have detected 85% of companions more massive than $0.05 M_{\odot}$ and 50% above $0.03 M_{\odot}$.Comment: 27 pages, 8 figures, 3 tables: accepted to the Astronomical Journa

Preservation of glaciochemical time-series in snow and ice from the Penny Ice Cap, Baffin Island

A detailed investigation of major ion concentrations of snow and ice in the summit region of Penny Ice Cap (PIC) was performed to determine the effects of summer melt on the glaciochemical time-series. While ion migration due to meltwater percolation makes it difficult to confidently count annual layers in the glaciochemical profiles, time-series of these parameters do show good structure and a strong one year spectral component, suggesting that annual to biannual signals are preserved in PIC glaciochemical records

Beginning Music Teacher Mentoring: Impact on Reflective Practice, Teaching Efficacy, and Professional Commitment

The purpose of this study was to investigate the status of mentoring and induction programs and their impacts on beginning music teachers. I measured mentoring program comprehensiveness, along with mentor functions and attributes, mentor support practices, and mentor effectiveness as perceived by mentees. I also explored the effects of mentee status, perceived mentor effectiveness, and mentor content area on reflective practice, teaching efficacy, and professional commitment. Data were collected from beginning music teachers within 10 states in Fall 2016 (N = 245) and again in March 2017 (n = 154). After using exploratory and confirmatory factor analysis techniques to reduce multi-item variables into smaller, latent factor structures, I utilized multivariate inferential statistics to explore whether beginning music teachers&rsquo; growth in reflective practice, teaching efficacy, and professional commitment over time was connected to mentor content area or mentor effectiveness (as perceived by the mentee). Then, I used path analysis techniques to explore relations among mentor and mentee characteristics, beginning teacher perceptions of mentor functions and effectiveness, and beginning music teachers&rsquo; self-reports of reflective practice, teaching efficacy, and professional commitment. Reflective practice, teaching efficacy, and professional commitment did not differ by mentee status (current, former). Additionally, perceived mentor effectiveness (as moderated by mentor content area) did not impact reflective practice, teaching efficacy, or professional commitment over time. In fact, mentees with non-music mentors reported increases in reflective practice, teaching efficacy, and professional commitment, but these gains were not statistically different from mentee respondents who were assigned a music mentor. Lastly, a measurement model that predicts professional commitment&mdash;including direct effects of Reflection-on-Action, Reflection-in-Action, and Classroom Management and Engagement efficacy, and indirect effects of Reflection-in-Action and mentee status&mdash;is proposed. Only mentee status predicted Classroom Management and Engagement efficacy; current mentees tended to be less efficacious. None of the other demographic or mentoring program variables&mdash;including mentor effectiveness, mentor content area, level of education, school setting, and years of teaching experience&mdash;predicted reflective practice, teaching efficacy, or professional commitment. Implications for beginning music teacher mentoring and recommendations for future research are discussed.</p

Forty-seven Years of Research on the Devon Island Ice Cap, Arctic Canada

The Devon Island ice cap has been the subject of scientific study for almost half a century, beginning with the first mass balance measurements in 1961. Research on the ice cap was the first to investigate (1) the role of meltwater in seasonal ice-velocity variations on a polythermal Arctic ice cap, (2) the use of air temperature rather than net radiation as a proxy for the energy driving surface melt, and (3) the influence of the changing frequency of specific synoptic weather configurations on glacier melt and mass balance. Other research has included investigations of ice cap geometry, flow dynamics, and mass balance; ice core analyses for records of past climate and contaminant deposition; and studies of changes in ice cap area and volume and their relationship to surface mass balance and ice dynamics. Current research includes ground studies connected to efforts to calibrate and validate the radar altimeter that will be carried by the European Space Agency’s (ESA) CryoSat2 satellite, and a major collaborative Canadian International Polar Year (IPY) project focused on the Belcher Glacier, on the northeast side of the ice cap, that examines hydrodynamics of large tidewater glaciers. This paper summarizes our current knowledge of the Devon Island ice cap and identifies some of the outstanding questions that continue to limit our understanding of climate-ice cap interactions in Arctic regions.La calotte glaciaire de l’île Devon fait l’objet d’une étude scientifique depuis près d’un demi-siècle, les premières mesures du bilan massique remontant à 1961. C’est la première fois que des travaux de recherche sur la calotte glaciaire permettent de faire enquête sur 1) le rôle de l’eau de fonte dans les variations caractérisant la vélocité de la glace d’une calotte glaciaire polytherme de l’Arctique; 2) l’utilisation de la température de l’air au lieu du bilan radiatif en surface en guise d’approximation pour la fonte superficielle conductrice d’énergie, et 3) l’influence exercée par la fréquence changeante de configurations climatiques synoptiques spécifiques sur la fonte du glacier et le bilan massique. Parmi les autres travaux de recherche, notons des enquêtes sur la géométrie de la calotte glaciaire, la dynamique des débits d’écoulement et le bilan massique; l’analyse des enregistrements relatifs aux carottes glaciaires en ce qui a trait à d’anciens dépôts climatiques et dépôts de contaminants; et l’étude des changements caractérisant l’aire et le volume de la calotte glaciaire de même que leur relation par rapport au bilan massique en surface et à la dynamique des glaces. Par ailleurs, les travaux de recherche actuels prennent la forme d’études sur le terrain se rapportant aux efforts visant à calibrer et à valider l’altimètre radar, études qui seront effectuées par le satellite CryoSat2 de l’Agence spatiale européenne (ASE), et un projet d’envergure en collaboration avec l’Année polaire internationale (API) au Canada portant sur le glacier Belcher, du côté nord-est de la carotte glaciaire, projet qui examine l’hydrodynamique des gros glaciers de marée. La présente communication résume nos connaissances actuelles de la calotte glaciaire de l’île Devon de même que certaines des questions en suspens qui continuent de restreindre la façon dont nous comprenons les interactions entre le climat et la calotte glaciaire dans les régions arctiques