3,860 research outputs found

    Teaching and Publishing with OER

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    Teaching and Publishing with OER was a presentation that was part of Building Bridges: Tools for Open Educational Resources (OER) Advocacy and Collaboration at TCUS Libraries , an online workshop held April 13th, 2021 1:00 P.M. - 4:00 P.M. Eastern Time

    Open Educational Resources for Innovative Pedagogy and Student Success

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    In this CETL presentation you will hear from faculty members who have completed Touro University’s Open Educational Resources (OER) Faculty Fellowship, with an introduction from Touro’s OER Librarian. We will discuss the possibilities for inspiration and innovation through using open educational practices, including tailoring learning materials to meet your students’ unique needs. Faculty fellows Stephanie Klinesmith and Michelle Buccinna will share their insights on completing the fellowship and creating OER materials for their courses. They will discuss how their projects have the potential to transform classroom teaching and learning. We invite you to join us for an engaging and dynamic session

    Population structure of graptolite assemblages

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    Graptolite rhabdosomes display a diverse suite of morphologies. The range of morphotypes present within most moderate to high diversity assemblages from the Ordovician and Silurian is similar, despite the different taxonomic composition of the faunas at different times. Survivorship analyses of graptolite faunas from the Ordovician and Silurian demonstrate strong similarities in the mortality rates of unrelated graptolites of similar functional morphology. It also shows a strong correlation of decreasing mortality rates amongst more mature colonies with increasing rhabdosome complexity. This similarity in both functional morphology and life history of graptolites suggests that they lived within a very stable planktic community structure

    Effects of Reduced Strength on Self-Selected Pacing for Long-Duration Activities

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    Strength and aerobic capacity are predictors of astronaut performance for extravehicular activities (EVA) during exploration missions. It is expected that astronauts will selfselect a pace below their ventilatory threshold (VT). PURPOSE: To determine the percentage of VT that subjects selfselect for prolonged occupational tasks. METHODS: Maximal aerobic capacity and a variety of lowerbody strength and power variables were assessed in 17 subjects who climbed 480 rungs on a ladder ergometer and then completed 10 km on a treadmill as quickly as possible using a selfselected pace. The tasks were performed on 4 days, with a weighted suit providing 0% (suit fabric only), 40%, 60%, and 80% of additional bodyweight (BW), thereby altering the strength to BW ratio. Oxygen consumption and heart rate were continuously measured. Repeated measures ANOVA and posthoc comparisons were performed on the percent of VT values under each suited condition. RESULTS: Subjects consistently selfpaced at or below VT for both tasks and the pace was related to suit weight. At the midpoint for the ladder climb the 80% BW condition elicited the lowest metabolic cost (19+/-14% below VT), significantly different than the 0% BW (3+/-16%, P=0.002) and the 40% BW conditions (5+/-22%, P=0.023). The 60% BW condition (13+/-19%) was different than the 40% BW condition (P=0.034). Upon completion of the ladder task there were no differences among the conditions (0%BW: 3+/-18%; 40%BW: 3+/-21%; 60%BW: 8+/-25%; 80%BW: 10+/-18%). All subjects failed to complete 5km at 80%BW. At the midpoint of the treadmill test the three remaining conditions were all significantly different (0%BW: 20+/-15%; 40%BW: 33+/-15%; 60%BW: 41+/-19%). Upon completion of the treadmill test the 60% BW condition (38+/-12%) was significantly different than the 40% BW (28+/-15%, P=0.024). CONCLUSIONS: Decreasing relative strength results in progressive and disproportionate decreases (relative to VT) in selfselected pacing during longduration activities. Thus, during prolonged, endurancetype activities, large reductions in strength cause notable performance decrements despite no changes in aerobic capacity. These data highlight the importance of both aerobic capacity and muscle strength to the performance of prolonged EVA in exploration mission scenarios

    Heart Rate Responses to Unaided Orion Side Hatch Egress in the Neutral Buoyancy Laboratory

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    NASA is developing the Orion capsule as a vehicle for transporting crewmembers to and from the International Space Station (ISS) and for future human space exploration missions. Orion and other commercial vehicles are designed to splash down in the ocean where nominally support personnel will assist crewmembers in egressing the vehicle. However, off-nominal scenarios will require crewmembers to egress the vehicle unaided, deploy survival equipment, and ingress a life raft. PURPOSE: To determine the heart rate (HR) responses to unaided Orion side hatch egress and raft ingress as a part of the NASA Crew Survival Engineering Team's evaluation of the PORT Orion mockup in the Neutral Buoyancy Laboratory (NBL). METHODS: Nineteen test subjects, including four astronauts (N=19, 14 males/5 females, 38.6+/-8.4 y, 174.4+/-9.6 cm, 75.7+/-13.1 kg), completed a graded maximal test on a cycle ergometer to determine VO2peak and HRpeak and were divided into five crews of four members each; one subject served on two crews. Each crew was required to deploy a life raft, egress the Orion vehicle from the side hatch, and ingress the life raft with two 8 kg emergency packs per crew. Each crew performed this activity one to three times; a total of ten full egresses were completed. Subjects wore a suit that was similar in form, mass, and function to the Modified Advanced Crew Escape Suit (MACES) including helmet, gloves, boots, supplemental O2 bottles, and a CO2-inflated life preserver (approx.18 kg); subjects began each trial seated supine in the PORT Orion mockup with seat belts and mockup O2 and communication connections and ended each trial with all four crewmembers inside the life raft. RESULTS: VO2peak was 40.8+/-6.8 mL/kg/min (3.1+/-0.7 L/min); HRpeak was 181+/-10 bpm. Total egress time across trials was 5.0+/-1.6 min (range: 2.8-8.0 min); all subjects were able to successfully complete all trials. Average maximum HR at activity start, at the hatch opening, in the water, and in the raft, was 108, 137, 147, and 153 bpm, respectively; these values corresponded to 59+/-10%, 73+/-8%, 82+/-3%, and 84+/-6% of HRpeak, respectively. The highest HRs were seen after raft ingress and ranged from 72-99% HRpeak. Across all trials, cumulative averages of 5.4, 3.0, 1.1, and 0.2 min were spent at HRs >60%, >70%, >80%, and >90% HRpeak, respectively. CONCLUSION: Unaided Orion side hatch egress in the NBL is a relatively short-duration activity that elicits a high HR response for several min. Although all crewmembers successfully completed this activity, additional factors such as high seas, poor visibility, an incapacitated crewmember, neurovestibular perturbation, and neuromuscular deconditioning characteristic of a true operational environment may increase the physiologic demand (or decrease crewmembers' physiologic capacity) of unaided Orion side hatch egress. Additionally, landing conditions may require the crewmembers to egress from the top hatch, which is expected to be even more physiologically demanding; this condition will be evaluated in subsequent collaborative testing with the NASA Crew Survival Engineering Team

    ELM Characteristics in MAST

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    Edge localized mode (ELM) characteristics in a large spherical tokamak (ST) with significant auxiliary heating are explored. High confinement is achieved in mega ampere spherical tokamak (MAST) at low ELM frequencies even though the ELMs exhibit many type III characteristics. These ELMs are associated with a reduction in the pedestal density but no significant change in the pedestal temperature or temperature profile, indicating that energy is convected from the pedestal region into the scrape-off layer. Power to the targets during an ELM arrives predominantly at the low field outboard side. ELM effluxes are observed up to 20 cm from the plasma edge at the outboard mid-plane and are associated with the radial motion of a feature at an average velocity of 0.75 km s-1. The target balance observed in MAST is potentially rather favourable for the ST since H-mode access is facilitated in a regime where ELM losses flow mostly to the large wetted area, outboard targets and, in addition, the target heat loads are reduced by an even distribution of power between the upper and lower targets

    Filamentary plasma eruptions : Results using the non-linear ballooning model

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    This paper provides an overview of recent results on two distinct studies exploiting the non-linear model for ideal ballooning modes with potential applications to edge-localized modes (ELMs). The non-linear model for tokamak geometries was developed by Wilson and Cowley in 2004 and consists of two differential equations that characterize the temporal and spatial evolution of the plasma displacement. The variation of the radial displacement along the magnetic field line is described by the first equation, which is identical to the linear ballooning equation. The second differential equation is a two-dimensional non-linear ballooning-like equation, which is often second order in time but can involve a fractional time derivative depending on the geometry. In the first study, the interaction of multiple filamentary eruptions is addressed in a magnetized plasma in a slab geometry. Equally sized filaments evolve independently in both the linear and non-linear regimes. However, if filaments are initiated with slightly different heights from the reference flux surface, they interact with each other in the non-linear regime: lower filaments are slowed down and are eventually completely suppressed, while the higher filaments grow faster because of the non-linear interaction. In the second study, this model of non-linear ballooning modes is examined quantitatively against experimental observations of ELMs in Mega Amp Spherical Tokamak (MAST) geometries. The results suggest that experimentally relevant results can only be obtained using modified equilibria

    The Wow Factor? A Comparative Study of the Development of Student Music Teachers' Talents in Scotland and Australia

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    For some time there has been debate about differing perspectives on musical gift and musical intelligence. One view is that musical gift is innate: that it is present in certain individuals from birth and that the task of the teacher is to develop the potential which is there. A second view is that musical gift is a complex concept which includes responses from individuals to different environments and communities (Howe and Sloboda, 1997). This then raises the possibility that musical excellence can be taught. We have already explored this idea with practising musicians (Stollery and McPhee, 2002). Our research has now expanded to include music teachers in formation, and, in this paper, we look at the influences in their musical development which have either 'crystallised' or 'paralysed' the musical talent which they possess. Our research has a comparative dimension, being carried out in Scotland and in Australia. We conclude that there are several key influences in the musical development of the individual, including home and community support, school opportunities and teaching styles and that there may be education and culture-specific elements to these influences

    BOUT++: a framework for parallel plasma fluid simulations

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    A new modular code called BOUT++ is presented, which simulates 3D fluid equations in curvilinear coordinates. Although aimed at simulating Edge Localised Modes (ELMs) in tokamak X-point geometry, the code is able to simulate a wide range of fluid models (magnetised and unmagnetised) involving an arbitrary number of scalar and vector fields, in a wide range of geometries. Time evolution is fully implicit, and 3rd-order WENO schemes are implemented. Benchmarks are presented for linear and non-linear problems (the Orszag-Tang vortex) showing good agreement. Performance of the code is tested by scaling with problem size and processor number, showing efficient scaling to thousands of processors. Linear initial-value simulations of ELMs using reduced ideal MHD are presented, and the results compared to the ELITE linear MHD eigenvalue code. The resulting mode-structures and growth-rate are found to be in good agreement (BOUT++ = 0.245, ELITE = 0.239). To our knowledge, this is the first time dissipationless, initial-value simulations of ELMs have been successfully demonstrated.Comment: Submitted to Computer Physics Communications. Revised to reduce page count. 18 pages, 16 figure
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