Work in Progress: Rigorously Assessing the Anecdotal Evidence of Increased Student Persistence in an Active, Blended, and Collaborative Mechanical Engineering Environment

This work in progress describes an ongoing study of an active, blended, and collaborative (ABC) course environment used in a core mechanical engineering course. This course has built on the growing body of literature citing active learning (Freeman et al., 2014), blended structures (Bowen & Ithaka, 2012), and collaborative engagement (Jeong & Chi, 2007) as positive influences on college and university science, technology, engineering, and math (STEM) outcomes. For the last six years, “Dynamics”, a core mechanical engineering course at a large public university, has utilized in-class activities, frequently-watched problem-solving videos, and a collaborative blog space to realize an ABC environment. On one key metric of course success, the rate of students who drop, fail, or withdraw from (DFW), the course has experienced near-constant improvements since the ABC structures were introduced. In this study, the authors utilize rigorous longitudinal methods to determine whether this drop in DFW rates can be directly attributed to increased implementation of ABC features. The authors hypothesize that as instructors become accustomed to the ABC environment and increase the level of in-class activity, use of blended resources, and collaboration, the likelihood of DFW in each subsequent year would drop. However, in the same time period, each subsequent class entered with higher levels of performance on proxy measures for prior knowledge. We therefore build a logistic regression model to predict individual-level DFW and determine whether the anecdotal drops in DFW that we observe can be attributed to the expansion of the ABC environment. More specifically, we predict likelihood of DFW based on students’ prior knowledge (grade in the preceding course, SAT math score), key demographics (gender, race/ethnicity), the semester and year they took Dynamics, their instructor, their year in school, and their major. We test for year fixed effects {year_t, t = 1, 2, ..., 7} to determine whether odds ratios for DFW consistently and significantly decrease over time. We also test for instructor effects, in particular for differences between the instructors who were involved in the design and development of the ABC environment and more independent instructors who only partially implemented the ABC course components. We anticipate results that will provide more rigorous, less biased, and efficient estimates for the individual- and class-level components that explain variance in DFW rates. These results would provide immediate implications for the next phase of our work, as we assess the next on-term implementation of the course in 2016. Our findings would also have long-term significance for other classes in mechanical engineering and related disciplines and for classes at other institutions that are considering implementing a comprehensive ABC learning environment

Transforming a Dynamics Course to an Active, Blended, and Collaborative Format: Focus on the Faculty

Mechanical engineering programs are increasingly applying educational research by transforming courses to be more interactive and to use a blend of online and face-to-face materials. However, the process of an existing course adopting these new practices is not well studied, and even less is understood about the faculty experience from on-boarding to delivery of a new curriculum or pedagogy. In this study, we follow the translation of an active, blended, and collaborative (ABC) curriculum for a core dynamics course from a large public university (where the ABC curriculum was developed) to a small private university. We use interpretive phenomenology to focus on the lived experience of the instructor newly implementing these course materials, format, and pedagogical approach. Specifically, we address the following research questions: (1) What is the lived experience of a mechanical engineering instructor at a different institution as she adopts and adapts the provided materials and format? (2) How does the experience of this instructor evolve throughout the semester? We use rich qualitative data to understand the experience of the instructor, who taught this course in its prior format and, in Fall 2015, taught the “off-term” core dynamics course via the new ABC structure. Through weekly reflection prompts, pre- and post-semester interviews, and supplementary process data (e.g., notes of weekly meetings between the new implementer and ABC team at the large public university), we describe and characterize the multi-faceted instructor experience. This includes her experience learning about the curriculum and online tools, implementing the class and adjusting her teaching practices, and assessing her students’ engagement with the course and understanding of dynamics concepts. Our findings suggest further areas of inquiry for studies of faculty practices around curriculum adoption, including probing opportunities for cross-institutional collaborations to share materials and transform courses, interrogating variation in mechanical engineering department and student cultures, and studying sources of faculty development and support throughout the course transformation process

Analyzing an Abbreviated Dynamics Concept Inventory and Its Role as an Instrument for Assessing Emergent Learning Pedagogies

The Dynamics Concept Inventory (DCI) is a validated assessment tool commonly used to evaluate student growth within core, gateway-level mechanics courses. This research explored the evaluative use of this tool within the context of Freeform – an emergent course system that buttresses active class meetings with blended and collaborative virtual learning environments, themselves founded upon extensive multimedia content and interactive forums – at Purdue University. The paper specifically considers a number of related issues including: (i) the thoughtful development (via expert content validation) and statistical reliability of an abbreviated DCI instrument, which is more amenable to in-class implementation than the much longer full DCI; (ii) the correlation of abbreviated-DCI performance with exam scores and final course grades for a dynamics course using the Freeform framework with an emphasis on both conceptual understanding and traditional problem-solving skills; and (iii) various inter-section performance metrics in a preliminary study on how an implementation of the abbreviated-DCI may help elucidate the impact of the instructor within the Freeform framework. The results of these analyses supported the validity and reliability of the abbreviated DCI tool, and demonstrated its usefulness in a formal research setting. The preliminary study suggested that the Freeform framework might normalize differences in instructor pedagogical choices and student performance across class sections. These findings indicate that the abbreviated DCI holds promise as a research instrument and lay the groundwork for future inquiry into the impact of the Freeform instructional framework on students and instructors alike

Examples of risk tools for pests in Peanut (Arachis hypogaea) developed for five countries using Microsoft Excel

Suppressing pest populations below economically-damaging levels is an important element of sustainable peanut (Arachis hypogaea L.) production. Peanut farmers and their advisors often approach pest management with similar goals regardless of where they are located. Anticipating pest outbreaks using field history and monitoring pest populations are fundamental to protecting yield and financial investment. Microsoft Excel was used to develop individual risk indices for pests, a composite assessment of risk, and costs of risk mitigation practices for peanut in Argentina, Ghana, India, Malawi, and North Carolina (NC) in the United States (US). Depending on pests and resources available to manage pests, risk tools vary considerably, especially in the context of other crops that are grown in sequence with peanut, cultivars, and chemical inputs. In Argentina, India, and the US where more tools (e.g., mechanization and pesticides) are available, risk indices for a wide array of economically important pests were developed with the assumption that reducing risk to those pests likely will impact peanut yield in a positive manner. In Ghana and Malawi where fewer management tools are available, risks to yield and aflatoxin contamination are presented without risk indices for individual pests. The Microsoft Excel platform can be updated as new and additional information on effectiveness of management practices becomes apparent. Tools can be developed using this platform that are appropriate for their geography, environment, cropping systems, and pest complexes and management inputs that are available. In this article we present examples for the risk tool for each country.Fil: Jordan, David L.. University of Georgia; Estados Unidos. North Carolina State University; Estados UnidosFil: Buol, Greg S.. North Carolina State University; Estados UnidosFil: Brandenburg, Rick L.. North Carolina State University; Estados UnidosFil: Reisig, Dominic. North Carolina State University; Estados UnidosFil: Nboyine, Jerry. Council for Scientific and Industrial Research Savanna Agricultural Research Institute; GhanaFil: Abudulai, Mumuni. Council for Scientific and Industrial Research Savanna Agricultural Research Institute; GhanaFil: Oteng Frimpong, Richard. Council for Scientific and Industrial Research Savanna Agricultural Research Institute; GhanaFil: Mochiah, Moses Brandford. Council for Scientific and Industrial Research Crops Research Institute; GhanaFil: Asibuo, James Y.. Council for Scientific and Industrial Research Crops Research Institute; GhanaFil: Arthur, Stephen. Council for Scientific and Industrial Research Crops Research Institute; GhanaFil: Akromah, Richard. Kwame Nkrumah University Of Science And Technology; GhanaFil: Mhango, Wezi. Lilongwe University Of Agriculture And Natural Resources; MalauiFil: Chintu, Justus. Chitedze Agricultural Research Service, Lilongwe; MalauiFil: Morichetti, Sergio. Aceitera General Deheza; ArgentinaFil: Paredes, Juan Andres. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Unidad de Fitopatología y Modelización Agrícola - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Fitopatología y Modelización Agrícola; ArgentinaFil: Monguillot, Joaquín Humberto. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Singh Jadon, Kuldeep. Central Arid Zone Research Institute, Jodhpur; IndiaFil: Shew, Barbara B.. North Carolina State University; Estados UnidosFil: Jasrotia, Poonam. Indian Institute Of Wheat And Barley Research, Karnal; IndiaFil: Thirumalaisamy, P. P.. India Council of Agricultural Research, National Bureau of Plant Genetic Resources; IndiaFil: Harish, G.. Directorate Of Groundnut Research, Junagadh; IndiaFil: Holajjer, Prasanna. National Bureau Of Plant Genetic Resources, New Delhi; IndiaFil: Maheshala, Nataraja. Directorate Of Groundnut Research, Junagadh; IndiaFil: MacDonald, Greg. University of Florida; Estados UnidosFil: Hoisington, David. University of Georgia; Estados UnidosFil: Rhoads, James. University of Georgia; Estados Unido

The Hubble Space Telescope Wide Field Camera 3 Early Release Science data: Panchromatic Faint Object Counts for 0.2-2 microns wavelength

We describe the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) Early Release Science (ERS) observations in the Great Observatories Origins Deep Survey (GOODS) South field. The new WFC3 ERS data provide calibrated, drizzled mosaics in the UV filters F225W, F275W, and F336W, as well as in the near-IR filters F098M (Ys), F125W (J), and F160W (H) with 1-2 HST orbits per filter. Together with the existing HST Advanced Camera for Surveys (ACS) GOODS-South mosaics in the BViz filters, these panchromatic 10-band ERS data cover 40-50 square arcmin at 0.2-1.7 {\mu}m in wavelength at 0.07-0.15" FWHM resolution and 0.090" Multidrizzled pixels to depths of AB\simeq 26.0-27.0 mag (5-{\sigma}) for point sources, and AB\simeq 25.5-26.5 mag for compact galaxies. In this paper, we describe: a) the scientific rationale, and the data taking plus reduction procedures of the panchromatic 10-band ERS mosaics; b) the procedure of generating object catalogs across the 10 different ERS filters, and the specific star-galaxy separation techniques used; and c) the reliability and completeness of the object catalogs from the WFC3 ERS mosaics. The excellent 0.07-0.15" FWHM resolution of HST/WFC3 and ACS makes star- galaxy separation straightforward over a factor of 10 in wavelength to AB\simeq 25-26 mag from the UV to the near-IR, respectively.Comment: 51 pages, 71 figures Accepted to ApJS 2011.01.2

LSST Science Book, Version 2.0

A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of the exciting science opportunities of the next decade. The Large Synoptic Survey Telescope (LSST) will have an effective aperture of 6.7 meters and an imaging camera with field of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over 20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a total point-source depth of r~27.5. The LSST Science Book describes the basic parameters of the LSST hardware, software, and observing plans. The book discusses educational and outreach opportunities, then goes on to describe a broad range of science that LSST will revolutionize: mapping the inner and outer Solar System, stellar populations in the Milky Way and nearby galaxies, the structure of the Milky Way disk and halo and other objects in the Local Volume, transient and variable objects both at low and high redshift, and the properties of normal and active galaxies at low and high redshift. It then turns to far-field cosmological topics, exploring properties of supernovae to z~1, strong and weak lensing, the large-scale distribution of galaxies and baryon oscillations, and how these different probes may be combined to constrain cosmological models and the physics of dark energy.Comment: 596 pages. Also available at full resolution at http://www.lsst.org/lsst/sciboo

Discovery of a Cosmological, Relativistic Outburst via its Rapidly Fading Optical Emission

We report the discovery by the Palomar Transient Factory (PTF) of the transient source PTF11agg, which is distinguished by three primary characteristics: (1) bright (R_peak = 18.3 mag), rapidly fading (ΔR = 4 mag in Δt = 2 days) optical transient emission; (2) a faint (R = 26.2 ± 0.2 mag), blue (g' – R = 0.17 ± 0.29 mag) quiescent optical counterpart; and (3) an associated year-long, scintillating radio transient. We argue that these observed properties are inconsistent with any known class of Galactic transients (flare stars, X-ray binaries, dwarf novae), and instead suggest a cosmological origin. The detection of incoherent radio emission at such distances implies a large emitting region, from which we infer the presence of relativistic ejecta. The observed properties are all consistent with the population of long-duration gamma-ray bursts (GRBs), marking the first time such an outburst has been discovered in the distant universe independent of a high-energy trigger. We searched for possible high-energy counterparts to PTF11agg, but found no evidence for associated prompt emission. We therefore consider three possible scenarios to account for a GRB-like afterglow without a high-energy counterpart: an "untriggered" GRB (lack of satellite coverage), an "orphan" afterglow (viewing-angle effects), and a "dirty fireball" (suppressed high-energy emission). The observed optical and radio light curves appear inconsistent with even the most basic predictions for off-axis afterglow models. The simplest explanation, then, is that PTF11agg is a normal, on-axis long-duration GRB for which the associated high-energy emission was simply missed. However, we have calculated the likelihood of such a serendipitous discovery by PTF and find that it is quite small (≈2.6%). While not definitive, we nonetheless speculate that PTF11agg may represent a new, more common (>4 times the on-axis GRB rate at 90% confidence) class of relativistic outbursts lacking associated high-energy emission. If so, such sources will be uncovered in large numbers by future wide-field optical and radio transient surveys

HST/STIS observations of GRB000301C: CCD imaging and NUV MAMA spectroscopy

We present HST/STIS observations of the optical counterpart (OT) of the gamma-ray burster GRB 000301C obtained on 2000 March 6, five days after the burst. CCD clear aperture imaging reveals a R ~ 21.50+/-0.15 source with no apparent host galaxy. An 8000 s, 1150 < lambda/A < 3300 NUV-MAMA prism spectrum shows a relatively flat continuum (in f_lambda) between 2800 and 3300 A, with a mean flux 8.7 (+0.8,-1.6)+/- 2.6 10^(-18) ergs/s/cm^2/A, and a sharp break centered at 2797+/-25 A. We interpret it as HI Lyman break at z = 2.067+/-0.025 indicating the presence of a cloud with a HI column density log(HI) > 18 on the line-of-sight to the OT. This value is conservatively a lower limit to the GRB redshift. However, the facts that large N(HI) system are usually considered as progenitors of present day galaxies and that other OTs are found associated with star forming galaxies strongly suggest that it is the GRB redshift. In any case, this represents the largest direct redshift determination of a gamma-ray burster to date. Our data are compatible with an OT spectrum represented by a power-law with an intrinsic index \alpha = 1.2((f_nu \propto nu^-alpha) and no extinction in the host galaxy or with alpha = 0.5 and extinction by a SMC-like dust in the OT rest-frame with A_V = 0.15. The large N(HI) and the lack of detected host is similar to the situation for damped Ly-alpha absorbers at z > 2.Comment: Replaced by final version. 10 p., 2 fig. Scheduled to appear in ApJ 555 n2 Jul 10, 2001. Minor changes, both redshift and mean near UV flux are revised with slightly larger values, due to a wrong offset sign in the wavelength calibratio

Very Early Optical Afterglows of Gamma-Ray Bursts: Evidence for Relative Paucity of Detection

Very early observations with the Swift satellite of gamma-ray burst (GRB) afterglows reveal that the optical component is not detected in a large number of cases. This is in contrast to the bright optical flashes previously discovered in some GRBs (e.g. GRB 990123 and GRB 021211). Comparisons of the X-ray afterglow flux to the optical afterglow flux and prompt gamma-ray fluence is used to quantify the seemingly deficient optical, and in some cases X-ray, light at these early epochs. This comparison reveals that some of these bursts appear to have higher than normal gamma-ray efficiencies. We discuss possible mechanisms and their feasibility for explaining the apparent lack of early optical emission. The mechanisms considered include: foreground extinction, circumburst absorption, Ly-alpha blanketing and absorption due to high redshift, low density environments, rapid temporal decay, and intrinsic weakness of the reverse shock. Of these, foreground extinction, circumburst absorption, and high redshift provide the best explanations for most of the non-detections in our sample. There is tentative evidence of suppression of the strong reverse shock emission. This could be because of a Poynting-flux-dominated flow or a pure non-relativistic hydrodynamical reverse shock.Comment: 22 pages, 5 figures. Accepted for publication in Ap