Late Registration and Student Success in On-Campus and Online Classes

The study examined the effect of late registration into on-campus and online classes upon student performance when accounting for completion of a college success skills course and the demographic factors of sex, race/ethnicity, age, and full-time/part-time enrollment status. The data source was 2010-2013 ex post facto data from 23 colleges in a large community college system in the southeastern United States. The statistical method of binary logistic regression was applied to the data. The regression models failed to yield strong predictions of the association between registration timing and student success. Coupled with previous studies, this study demonstrated that the presumed negative interaction between late registration and student success is misplaced. Researchers should turn their attention to student characteristics and behaviors that hold more promise for actionable findings. Colleges should develop more global and integrated strategies for improving student success instead of narrowly focusing on eliminating late registration

At Issue: A Comprehensive Review and Synthesis of the Literature on Late Registration

Using a literature review taxonomy described by Cooper and Hedges (2009), an analysis of 32 publicly available studies of late registrations was conducted to provide researchers and policymakers with an assessment of the extent, quality, and major findings of the studies. The reviewer asserted that few high-quality studies have been conducted on late registration, and the research does not provide strong evidence that late registration is associated with poor student outcomes. The review provided answers to the following questions: What does the body of research on late registration indicate about the advisability of retaining it as an option for students? What research methods--and of what quality--have been employed? What research remains to be done? What are the implications for policy and college operations

A Comparative Analysis of SafeAssign and Turnitin

The plagiarism detection programs SafeAssign and Turnitin are commonly used at the collegiate level to detect improper use of outside sources. In order to determine whether either program is superior, this study evaluated the programs using four standards: (1) the ability to detect legitimate plagiarism, (2) the ability to avoid false positives, (3) the ease of use in design, and (4) cost. After submitting 284 texts to both programs—including a random sampling of anonymous student texts from different disciplines; a sample of autobiographies, which were unlikely to be plagiarized; and a sample of texts assembled from online sources which were completely plagiarized—no statistically significant difference between the effectiveness of the programs was found

Turbine Powered Simulator Calibration and Testing for Hybrid Wing Body Powered Airframe Integration

Propulsion airframe integration testing on a 5.75% scale hybrid wing body model us- ing turbine powered simulators was completed at the National Full-Scale Aerodynamics Complex 40- by 80-foot test section. Four rear control surface con gurations including a no control surface de ection con guration were tested with the turbine powered simulator units to investigate how the jet exhaust in uenced the control surface performance as re- lated to the resultant forces and moments on the model. Compared to ow-through nacelle testing on the same hybrid wing body model, the control surface e ectiveness was found to increase with the turbine powered simulator units operating. This was true for pitching moment, lift, and drag although pitching moment was the parameter of greatest interest for this project. With the turbine powered simulator units operating, the model pitching moment was seen to increase when compared to the ow-through nacelle con guration indicating that the center elevon and vertical tail control authority increased with the jet exhaust from the turbine powered simulator units

The first Forecasters Handbook for West Africa

Bridging the gap between rapidly moving scientific research and specific forecasting tools, Meteorology of Tropical West Africa: The Forecasters' Handbook’, gives unprecedented access to the latest science and combines this with pragmatic approaches to forecasting. It is set to change the way forecasters, researchers and students learn about tropical meteorology and will serve to drive demand for new forecasting tools. The Handbook builds upon the legacy of the AMMA project, making the latest science applicable to forecasting in the region. By bringing together, at the outset, researchers and forecasters from across the region, and linking to applications, user communities and decision-makers, the Forecasters’ Handbook provides a template for finding much needed solutions to critical issues such as building resilience to climate change in West Africa

Experimental Evaluation of Inlet Distortion on an Ejector Powered Hybrid Wing Body at Take-off and Landing Conditions

As part of the NASA Environmentally Responsible Aircraft project, an ultra high bypass ratio engine integration on a hybrid wing body demonstration was planned. The goal was to include engine and airframe integration concepts that reduced fuel consumption by at least 50% while still reducing noise 42 db cumulative on the ground. Since the engines would be mounted on the upper surface of the aft body of the aircraft, the inlets may be susceptible to vortex ingestion from the wing leading edge at high angles of attack and sideslip, and separated wing/body flow. Consequently, experimental and computational studies were conducted to collect flow surveys useful for characterizing engine operability. The wind tunnel tests were conducted at two NASA facilities, the 14- by 22-foot at NASA Langley and the 40- by 80-foot at NASA Ames Research Center. The test results included in this paper show that the distortion and pressure recovery levels were acceptable for engine operability. The CFD studies conducted to compare to experimental data showed excellent agreement for the angle of attacks examined, although failed to match the low speed experimental data at high sideslip angles

PEARLS: Low Stellar Density Galaxies in the El Gordo Cluster Observed with JWST

A full understanding of how unusually large "Ultra Diffuse Galaxies" (UDGs) fit into our conventional understanding of dwarf galaxies remains elusive, despite the large number of objects identified locally. A natural extension of UDG research is the study of similar galaxies at higher redshift to establish how their properties may evolve over time. However, this has been a challenging task given how severely systematic effects and cosmological surface brightness dimming inhibit our ability to study low-surface brightness galaxies at high-$z$. Here, we present an identification of low stellar surface density galaxies (LDGs), likely the progenitors of local UDGs, at moderate redshift with deep near-IR observations of the El Gordo cluster at $z = 0.87$ with JWST. By stacking 8 NIRCAM filters, we are able to achieve an apparent surface brightness sensitivity of $24.59$ mag arcsec$^{-2}$, faint enough to be complete to the bright end of the LDG population. Our analysis identifies significant differences between this population and local UDGs, such as their color and size distributions, which suggest that UDG progenitors are bluer and more extended at high-$z$ than at $z = 0$. This suggests that multiple mechanisms are responsible for UDG formation and that prolonged transformation of cluster dwarfs is not a primary UDG formation mechanism at high-$z$. Furthermore, we find a slight overabundance of LDGs in El Gordo, and, in contrast to findings in local clusters, our analysis does not show a deficit of LDGs in the center of El Gordo, implying that tidal destruction of LDGs is significant between $z = 0.87$ and $z = 0$.Comment: Resubmitted to ApJ after minor revision

Conceptual design of large-bore superconducting quadrupoles with active magnetic shielding for the AHF

The Advanced Hydrotest Facility, under study by LANL, utilizes large-bore superconducting quadrupole magnets. In the paper we discuss the conceptual design of such quadrupoles using active shielding. The magnets are specified to achieve gradients of up to 24T/m with a 28-cm warm bore and to have 0.01% field quality. Concepts for the magnet cryosystems and quench protection are also briefly discussed to confirm the reliability of the proposed design

Magellanic System Stars Identified in the SMACS J0723.3-7327 JWST ERO Images

We identify 68 distant stars in JWST/NIRCam ERO images of the field of galaxy cluster SMACS J0723.3-7327 (SMACS 0723). Given the relatively small ($\sim$$10^{\circ}$) angular separation between SMACS 0723 and the Large Magellanic Cloud, it is likely that these stars are associated with the LMC outskirts or Leading Arm. This is further bolstered by a spectral energy distribution analysis, which suggests an excess of stars at a physical distance of $40-100$ kpc, consistent with being associated with or located behind the Magellanic system. In particular, we find that the overall surface density of stars brighter than 27.0 mag in the field of SMACS 0723 is $\sim$2.3 times that of stars in a blank field with similar galactic latitude (the North Ecliptic Pole Time Domain Field), and that the density of stars in the SMACS 0723 field with SED-derived distances consistent with the Magellanic system is $\sim$7.3 times larger than that of the blank field. The candidate stars at these distances are consistent with a stellar population at the same distance modulus with [Fe/H] $= -1.0$ and an age of $\sim$$5.0$ Gyr. On the assumption that all of the 68 stars are associated with the LMC, then the stellar density of the LMC at the location of the SMACS 0723 field is $\sim$$710$ stars kpc$^{-3}$, which helps trace the density of stars in the LMC outskirts.Comment: Submitted to ApJ, comments welcom

PEARLS: A Potentially Isolated Quiescent Dwarf Galaxy with a TRGB Distance of 31 Mpc

A wealth of observations have long suggested that the vast majority of isolated classical dwarf galaxies ($M_*=10^7$-$10^9$ M$_\odot$) are currently star-forming. However, recent observations of the large abundance of "Ultra-Diffuse Galaxies" beyond the reach of previous large spectroscopic surveys suggest that our understanding of the dwarf galaxy population may be incomplete. Here we report the serendipitous discovery of an isolated quiescent dwarf galaxy in the nearby Universe, which was imaged as part of the PEARLS GTO program. Remarkably, individual red-giant branch stars are visible in this near-IR imaging, suggesting a distance of $31$ Mpc, and a wealth of archival photometry point to an sSFR of $2\times10^{-12}$ yr$^{-1}$. Spectra obtained with the Lowell Discovery Telescope find a recessional velocity consistent with the Hubble Flow and ${>}1500$ km/s separated from the nearest massive galaxy in SDSS, suggesting that this galaxy was either quenched from internal mechanisms or had a very high-velocity interaction with a nearby massive galaxy in the past. This analysis highlights the possibility that many nearby quiescent dwarf galaxies are waiting to be discovered and that JWST has the potential to identify them.Comment: Submitted to ApJ Letters. Comments welcome