9,615 research outputs found

    Design criteria for payload workstation accommodations

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    Anticipated shuttle sortie payload man-system design criteria needs are investigated. Man-system interactions for the scientific disciplines are listed and the extent is assessed to which documented Skylab experience is expected to provide system design guidance for each of the identified interactions. Where the analysis revealed that the reduced Skylab data does not answer the anticipated needs candidate criteria, based on unreduced Skylab data, available prior research, original analysis, or related requirements derived from previous space programs, are provided

    An investigation into the archaeological application of carbon stable isotope analysis used to establish crop water availability: solutions and ways forward

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    Carbon stable isotope analysis of charred cereal remains is a relatively new method employed by archaeological scientists to investigate ancient climate and irrigation regimes. The aim of this study was to assess the effect of environmental variables on carbon isotope discrimination (D) in multiple environments to develop the technique and its archaeological application, using crops grown at three experimental stations in Jordan. There are two key results: (1) as expected, there was a strong positive relationship between water availability and D; (2) site, not water input, was the most important factor in determining D. Future work should concentrate on establishing ways of correcting D for the influence of site specific environmental variables and on assessing how well carbon isotope discrimination values are preserved within the archaeological record

    Interrelationships between tracking performance measures, control dynamics, and the effects of incentives

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    Interrelationships between tracking performance measures, control dynamics, and effects of incentive

    Miniature infrared data acquisition and telemetry system

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    The Miniature Infrared Data Acquisition and Telemetry (MIRDAT) Phase 1 study was performed to determine the technical and commercial feasibility of producing a miniaturized electro-optical telemetry system. This system acquires and transmits experimental data from aircraft scale models for realtime monitoring in wind tunnels. During the Phase 1 study, miniature prototype MIRDAT telemetry devices were constructed, successfully tested in the laboratory and delivered to the user for wind tunnel testing. A search was conducted for commercially available components and advanced hybrid techniques to further miniaturize the system during Phase 2 development. A design specification was generated from laboratory testing, user requirements and discussions with component manufacturers. Finally, a preliminary design of the proposed MIRDAT system was documented for Phase 2 development

    A Study of Variables that Influence Teacher Turnover in the Little Municipal School District

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    A teacher shortage is a recognized problem in research on public schools. Schools across the United States must hire and retain highly qualified teachers, but the literature indicates teachers with fewer than 3 years of experience are often leaving teaching, creating a possible teacher shortage of 4.2 million teachers by the year of 2016. Retaining teachers with less than 3 years of experience is a definite problem in the Little Municipal School District (LMSD). In response to the failure of the LMSD to retain teachers with less experience, a study was conducted to identify the variables effecting teacher turnover. Determining the reasons teachers leave LMSD and facing those issues can assist in addressing the conditions associated with teacher turnover. This study focused on variables teachers with 3 or fewer years of experience indicate as their reasons for leaving. These variables were compared to studies conducted by Veenman (1988), Ganser (1994), and Ingersoll (2003), leading authorities on teacher retention. The results of this research suggest that teachers with less experience are leaving the LMSD because of pressure to achieve higher state test scores, lack of motivated students, insufficient materials and supplies, heavy teaching loads, inadequate guidance and support, poor relations with principals and administrators, lack of classroom discipline, and the burden of clerical work. Recommendations for LMSD include adding four programs to the district: a district-wide mentoring program for less experienced teachers; a teacher–liaison to improve communications between new teachers and administrators; a yearly review of materials to keep classroom materials current; and an incentive program for students to motivate students to achieve. Recommendations for further research include more studies on why teachers remain in low turnover districts, and did teacher’s preparation (alternative vs. traditional) affect retention

    The acoustic complex and its relations in the brain of the opossum (Didelphys Virginiana)

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    No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49598/1/1000120402_ftp.pd

    A Descriptive Study of Implementing Tiered Systematic Phonics Intervention Through the Colorado Read Act

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    The research question explored in this capstone was, how might I aid schools and districts in implementing district-wide systematic phonics intervention, both instructionally and organizationally? It documents Denver Public Schools (DPS) efforts to implement the READ act, a comprehensive law in which all students are evaluated in reading and assigned intervention if needed. The capstone explores how DPS can implement tiered systematic phonics intervention as part of the READ act. The paper reviews the most current peer reviewed research regarding the efficacy of phonics intervention. Using the methodology of a descriptive study, the capstone lays out a detailed logistical proposal of how students can be assessed and assigned tiered levels of intervention. The capstone then details research-based instructional practices, assessment tools, and lesson plan resources for implementing effective phonics intervention

    Impedance of a sphere oscillating in an elastic medium with and without slip

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    The dynamic impedance of a sphere oscillating in an elastic medium is considered. Oestreicher's formula for the impedance of a sphere bonded to the surrounding medium can be expressed simply in terms of three lumped impedances associated with the displaced mass and the longitudinal and transverse waves. If the surface of the sphere slips while the normal velocity remains continuous, the impedance formula is modified by adjusting the definition of the transverse impedance to include the interfacial impedance.Comment: 10 pages, 2 figure

    The structure of an LIM-only protein 4 (LMO4) and deformed epidermal autoregulatory factor-1 (DEAF1) complex reveals a common mode of binding to LMO4

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    LIM-domain only protein 4 (LMO4) is a widely expressed protein with important roles in embryonic development and breast cancer. It has been reported to bind many partners, including the transcription factor Deformed epidermal autoregulatory factor-1 (DEAF1), with which LMO4 shares many biological parallels. We used yeast two-hybrid assays to show that DEAF1 binds both LIM domains of LMO4 and that DEAF1 binds the same face on LMO4 as two other LMO4-binding partners, namely LIM domain binding protein 1 (LDB1) and C-terminal binding protein interacting protein (CtIP/RBBP8). Mutagenic screening analysed by the same method, indicates that the key residues in the interaction lie in LMO4LIM2 and the N-terminal half of the LMO4-binding domain in DEAF1. We generated a stable LMO4LIM2-DEAF1 complex and determined the solution structure of that complex. Although the LMO4-binding domain from DEAF1 is intrinsically disordered, it becomes structured on binding. The structure confirms that LDB1, CtIP and DEAF1 all bind to the same face on LMO4. LMO4 appears to form a hub in protein-protein interaction networks, linking numerous pathways within cells. Competitive binding for LMO4 therefore most likely provides a level of regulation between those different pathways.SJ was funded by an Australian Postgraduate Award (education.gov.au/australian-postgraduate-awards). JPM and JMM were awarded Senior Research Fellowships from the Australian National and Medical Research Council (www.nhmrc.gov.au). This project was funded by an Australian Research Council (www. arc.gov.au) Discovery Project Grant (DP110104332) to JMM and LC

    Thin-film flow in helically wound rectangular channels with small torsion

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    Laminar gravity-driven thin-film flow down a helically-wound channel of rectangular cross-section with small torsion in which the fluid depth is small is considered. Neglecting the entrance and exit regions we obtain the steady-state solution that is independent of position along the axis of the channel, so that the flow, which comprises a primary flow in the direction of the axis of the channel and a secondary flow in the cross-sectional plane, depends only on position in the two-dimensional cross-section of the channel. A thin-film approximation yields explicit expressions for the fluid velocity and pressure in terms of the free-surface shape, the latter satisfying a non-linear ordinary differential equation that has a simple exact solution in the special case of a channel of rectangular cross-section. The predictions of the thin-film model are shown to be in good agreement with much more computationally intensive solutions of the small-helix-torsion Navier–Stokes equations. The present work has particular relevance to spiral particle separators used in the mineral-processing industry. The validity of an assumption commonly used in modelling flow in spiral separators, namely that the flow in the outer region of the separator cross-section is described by a free vortex, is shown to depend on the problem parameters
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