691 research outputs found
Student Perceptions and Learning Outcomes: Evidence from the Education Testing Service (ETS) Major Field Test in Business
We examine course evaluation data from the core finance course and analyze how these data relate to performance on the finance portion of the Educational Testing Service Major Field Test in Business (ETS). We find that gender, SAT scores, GPA and concentration all have significant impacts on student performance. We also find that student perceptions of teaching and of how much knowledge they gained do not relate to the finance ETS score. Finally, we find that students who feel challenged in their finance core course do significantly better on the finance portion of the exam. This result is robust to different data partitions
Wheelchair-based game design for older adults
Few leisure activities are accessible to institutionalized older adults using wheelchairs; in consequence, they experience lower levels of perceived health than able-bodied peers. Video games have been shown to be an engaging leisure activity for older adults. In our work, we address the design of wheelchair-accessible motion-based games. We present KINECTWheels, a toolkit designed to integrate wheelchair movements into motion-based games, and Cupcake Heaven, a wheelchair-based video game designed for older adults using wheelchairs. Results of two studies show that KINECTWheels can be applied to make motion-based games wheelchair-accessible, and that wheelchair-based games engage older adults. Through the application of the wheelchair as an enabling technology in play, our work has the potential of encouraging older adults to develop a positive relationship with their wheelchair. Copyright 2013 ACM
Observation of Classroom Performance Using Therapy Balls as a Substitute for Chairs in Elementary School Children
Many classrooms are beginning to substitute standard chairs with therapy balls, which help to improve studentsâ focus and classroom performance, according to teacher and student reports. Researchers conducted an observational study in a classroom at a local elementary school that implemented therapy balls. For each hour-long observation, three independent researchers marked seated behaviors of students (N=19). The first observation was conducted when students were using standard chairs, and two more were conducted when students used therapy balls during classroom activities. Researchers observed the behaviors of students on the given seating device, including academic task (on/off task), effort level, attitude, interactions, seated behavior (bouncing/rocking/stationary/other), and intensity level of participation in classroom activities. Analysis of the collected data demonstrates that 50% of observations when students were seated on standard chairs indicated on task behavior, while 85% of observations when students were seated on therapy balls were recorded as on task behavior. In addition, movement while seated increased on the therapy balls (35% of observations indicated stationary seated behavior) compared to the standard chairs (47% observations indicated stationary seated behavior). The increased rocking and bouncing seated behavior on the therapy balls suggests that the seating device helps to engage the vestibular system. In addition, stationary behavior on therapy balls was often classified as proprioceptive. The results from the observational study will allow researchers to further investigate whether or not engaging the vestibular system can help to improve performance on functional school skills
Biomechanical and Proprioceptive Differences during Drop Landings between Dancers and Non-dancers
International Journal of Exercise Science 6(4) : 289-299, 2013. The focus of this research was to determine if female dancers have differing kinematic and kinetic characteristics when landing from three heights (0.2, 0.5, and 0.8 m) both with and without vision compared to non-dancers. It was hypothesized that dancers would show differing kinematic and kinetic patterns of control due to their increased proprioceptive awareness. Eight collegiate dancers and seven collegiate controls who were neither dancers nor collegiate jumping athletes volunteered for this study. Sagittal plane lower limb joint angles were measured at 100 Hz prior to landing through stability with a high-speed camera, and peak vertical ground reaction forces relative to body weight were recorded with an indwelling force plate. Results indicated biomechanical differences across height and vision conditions, as well as between groups. Kinetic results showed a significant height effect with respect to vertical ground reaction forces. From the 0.8 m drop, both dancers and non-dancers produced significantly greater ground reaction forces when landing without vision compared to when they landed with vision. No significant kinetic differences were found between groups. Kinematic results revealed a significant height effect for the hip and knee angles across groups and vision conditions, meaning that as drop height increased, the participants demonstrated greater range of motion in their hip and knee joints. Dancers and non-dancers responded differently when dropping from 0.8 m without vision. Dancers significantly increased hip flexion compared to landing with vision, while non-dancers tended to stiffen up and reduced hip flexion. These findings suggest that dancers utilize proprioceptive input more effectively as they adopted a hip strategy (flexion of the hips) to maintain stability. Training dancers without vision may impact dance instruction and reduce the risk of injuries when landing
Impact-Induced Chondrule Deformation and Aqueous Alteration of CM2 Murchison
Deformed chondrules in CM2 Murchison have been found to define a prominent foliation [1,2] and lineation [3] in 3D using X-ray computed tomography (XCT). It has been hypothesized that chondrules in foliated chondrites deform by "squeezing" into surrounding pore space [4,5], a process that also likely removes primary porosity [6]. However, shock stage classification based on olivine extinction in Murchison is consistently low (S1-S2) [4-5,7] implying that significant intracrystalline plastic deformation of olivine has not occurred. One objective of our study is therefore to determine the microstructural mechanisms and phases that are accommodating the impact stress and resulting in relative displacements within the chondrules. Another question regarding impact deformation in Murchison is whether it facilitated aqueous alteration as has been proposed for the CMs which generally show a positive correlation between degree of alteration and petrofabric strength [7,2]. As pointed out by [2], CM Murchison represents a unique counterpoint to this correlation: it has a strong petrofabric but a relatively low degree of aqueous alteration. However, Murchison may not represent an inconsistency to the proposed causal relationship between impact and alteration, if it can be established that the incipient aqueous alteration post-dated chondrule deformation. Methods: Two thin sections from Murchison sample USNM 5487 were cut approximately perpendicular to the foliation and parallel to lineation determined by XCT [1,3] and one section was additionally polished for EBSD. Using a combination of optical petrography, SEM, EDS, and EBSD several chondrules were characterized in detail to: determine phases, find microstructures indicative of strain, document the geometric relationships between grain-scale microstructures and the foliation and lineation direction, and look for textural relationships of alteration minerals (tochilinite and Mg-Fe serpentine) that indicate timing of their formation relative to deformation event(s). Preliminary Results: Deformed chondrules are dominated by forsterite and clinoenstatite with lesser amounts of Fe-Mg serpentine, sulfides, and low calcium pyroxene. Olivine grains are commonly fractured but generally show sharp optical extinction. The pyroxene, in contrast, is not only fractured but also often displays undulose extinction. In addition, the clinoenstatite is frequently twinned but it is unclear whether the twins are the result of mechanical deformation or inversion from protoenstatite [8]. EBSD work is currently ongoing to determine if areas of higher crystallographic strain can be imaged and mapped, and to determine the pyroxene twin orientations. In regards to alteration, we have found evidence for post-deformation formation of tochilinite and Mg-Fe serpentine indicating that aqueous alteration has indeed post-dated the deformation of the chondrules
Centering mental health and wellbeing in practices of mentoring undergraduate research
Due to the great amount of uncertainty caused by worldwide events, the mental health of college students has been greatly impacted. This article discusses two evidenced-based frameworks (i.e., Act-Belong-Commit and Ten Salient Practices) that undergraduate research mentors can keep in mind to center the mental health of their students in their practice
Evidence for surface uplift of the Atlas Mountains and the surrounding peripheral plateaux: Combining apatite fission-track results and geomorphic indicators in the Western Moroccan Meseta (coastal Variscan Paleozoic basement)
This work represents an initial attempt to link the evolution of the topography in relation to the general tectonic framework of western Morocco. For this purpose, in a section of the Western Moroccan Meseta different tools are combined in order to attain the general objective. Apatite fission-track (AFT) data of granitic rocks of the RabatâKhenifra area give ages around 200 Ma with track length distributions which are compatible with the thermal models already established for the area. An inverse correlation between AFT ages and elevation is observed which is compatible with previous models indicating northward tilting of the whole Western Moroccan Meseta which is younger than 20â25 Ma. In order to test this possibility a detailed analysis of the topography at different scales in the Western Moroccan Meseta has been performed. Results indicate that two open folds with different amplitudes are recognized and that the one with wider wavelength could correspond to a lithospheric fold as previously stated by other authors on the basis of independent geological arguments. The northward tilting proposed based on the AFT data agrees with the results obtained in the analysis of the topography which reinforces the presence of a very open fold with a wavelength of 200â300 km in the north-western limb of the Western Moroccan Meseta
Chemical abrasion: the mechanics of zircon dissolution
Chemical abrasion is a technique that combines thermal annealing and partial
dissolution in hydrofluoric acid (HF) to selectively remove
radiation-damaged portions of zircon crystals prior to UâPb isotopic
analysis, and it is applied ubiquitously to zircon prior to UâPb isotope
dilution thermal ionization mass spectrometry (ID-TIMS). The mechanics of
zircon dissolution in HF and the impact of different leaching conditions on
the zircon structure, however, are poorly resolved. We present a
microstructural investigation that integrates microscale X-ray computed
tomography (”CT), scanning electron microscopy, and Raman
spectroscopy to evaluate zircon dissolution in HF. We show that ”CT
is an effective tool for imaging metamictization and complex dissolution
networks in three dimensions. Acid frequently reaches crystal interiors via
fractures spatially associated with radiation damage zoning and inclusions
to dissolve soluble high-U zones, some inclusions, and material around
fractures, leaving behind a more crystalline zircon residue. Other acid paths
to crystal cores include the dissolution of surface-reaching inclusions and
the percolation of acid across zones with high defect densities. In highly
crystalline samples dissolution is crystallographically controlled with
dissolution proceeding almost exclusively along the c axis. Increasing the
leaching temperature from 180 to 210ââC results in
deeper etching textures, wider acid paths, more complex internal dissolution
networks, and greater volume losses. How a grain dissolves strongly depends
on its initial radiation damage content and defect distribution as well as
the size and position of inclusions. As such, the effectiveness of any
chemical abrasion protocol for ID-TIMS UâPb geochronology is likely
sample-dependent. We also briefly discuss the implications of our findings
for deep-time (U-Th)/He thermochronology.</p
Does Student Performance in Introductory Economics and Business Courses Impact ETS Scores?
This study examines the impact of economics education on student performance on the Educational Testing Service Major Field Test in Business. We demonstrate that grades in introductory microeconomics and macroeconomics courses have a positive relationship with overall exam performance as well as sub-scores in most content areas of the test. Furthermore, we use a measure of âextranormalâ ability in economics and demonstrate its positive relationship to test performance. âExtranormalâ ability represents the portion of course grades that cannot be explained by prior academic achievement. Finally, we show that the relationship between âextranormalâ ability and exam performance is much more limited for female students than for male students
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