1,543 research outputs found

    Method of fabricating a photovoltaic module of a substantially transparent construction

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    A method characterized by the steps of positioning a plurality of uniformly dimensioned photovoltaic cells in registered relation with a plurality of openings formed in a planar tool is disclosed. The method allows acess to the P contact surface of each of the cells. The steps of the method are: (1) connecting the N contact surface of alternate cells to the P contact surface of the cells interposed therebetween, (2) removing therefrom residue of solder flux, (3) applying to the N contact surfaces of the cells a transparent adhesive, (4) placing a common transparent cover plate in engaged relation with the adhesive, (5) placing a film over the circular openings for hermetically sealing the openings, and (6) establishing a vacuum between the film and the cover plate

    Predictive factors of brachial plexus neuropathy in wrestling athletes: A prospective longitudinal study

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    Context. Brachial plexus neuropathies are prevalent within wrestling. Objective. The purpose was to examine possible predisposing factors to brachial plexus neuropathy. Design. This study was a prospective longitudinal study. Setting. An athletic training room at an Eastern Wrestling League University (EWL). Patients and other participants. Twenty-three collegiate wrestlers ranging in age from 19.83 +/- 1.62 years volunteered to participate. Interventions. Neck strength, Head-neck segment, Head-neck length, and neck girth were measured. Previous history and number of years of wrestling were measured using a questionnaire. Main outcome measures. Neck strength and previous history may predispose wrestlers to brachial plexus neuropathy. Results. There was a main effect for neck strength in the directions of right and left lateral flexion for Time. All other analyses were not significant. Conclusion. Trends indicate that a larger sample size may allow effects to be noted. Further research is necessary to examine these possible effects

    Confinement induced instability of thin elastic film

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    A confined incompressible elastic film does not deform uniformly when subjected to adhesive interfacial stresses but with undulations which have a characteristic wavelength scaling linearly with the thickness of the film. In the classical peel geometry, undulations appear along the contact line below a critical film thickness or below a critical curvature of the plate. Perturbation analysis of the stress equilibrium equations shows that for a critically confined film the total excess energy indeed attains a minima for a finite amplitude of the perturbations which grow with further increase in the confinement.Comment: 11 pages, 6 figure

    A Behavioral Confirmation and Reduction of the Natural versus Synthetic Drug Bias

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    Research reveals a biased preference for natural versus synthetic drugs; however, this research is based upon self-report and has not examined ways to reduce the bias. We examined these issues in five studies involving 1,125 participants. In a Pilot Study (N = 110), participants rated the term natural to be more positive than the term synthetic, which reveals a default natural-is-better belief. In Studies 1 (N = 109) and 2 (N = 100), after a supposed personality study, participants were offered a thank you “gift” of a natural or synthetic pain reliever. Approximately 86% (Study 1) and 93% (Study 2) of participants chose the natural versus synthetic pain reliever, which provide a behavioral choice confirmation of the natural drug bias. In Studies 3 (N = 350) and 4 (N = 356), participants were randomly assigned to a control or experimental condition and were asked to consider a scenario in which they had a medical issue requiring a natural versus synthetic drug. The experimental condition included a stronger (Study 3) or weaker (Study 4) rational appeal about the natural drug bias and a statement suggesting that natural and synthetic drugs can be good or bad depending upon the context. In both studies, the natural bias was reduced in the experimental condition, and perceived safety and effectiveness mediated this effect. Overall, these data indicate a bias for natural over synthetic drugs in preferences and behavioral choices, which might be reduced with a rational appeal

    An autobiography of hands: on training in sleight of hand magic

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    Set in an autobiographical frame, this text describes the intensive process of training in sleight of hand magic, what happened when this training was subsequently abandoned, and how it is now being resumed

    Measurements of quasi-particle tunneling in the nu = 5/2 fractional quantum Hall state

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    Some models of the 5/2 fractional quantum Hall state predict that the quasi-particles, which carry the charge, have non-Abelian statistics: exchange of two quasi-particles changes the wave function more dramatically than just the usual change of phase factor. Such non-Abelian statistics would make the system less sensitive to decoherence, making it a candidate for implementation of topological quantum computation. We measure quasi-particle tunneling as a function of temperature and DC bias between counter-propagating edge states. Fits to theory give e*, the quasi-particle effective charge, close to the expected value of e/4 and g, the strength of the interaction between quasi-particles, close to 3/8. Fits corresponding to the various proposed wave functions, along with qualitative features of the data, strongly favor the Abelian 331 state

    Land use change detection with LANDSAT-2 data for monitoring and predicting regional water quality degradation

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    The author has identified the following significant results. Comparison between LANDSAT 1 and 2 imagery of Arkansas provided evidence of significant land use changes during the 1972-75 time period. Analysis of Arkansas historical water quality information has shown conclusively that whereas point source pollution generally can be detected by use of water quality data collected by state and federal agencies, sampling methodologies for nonpoint source contamination attributable to surface runoff are totally inadequate. The expensive undertaking of monitoring all nonpoint sources for numerous watersheds can be lessened by implementing LANDSAT change detection analyses

    Fundamentals of Flakeboard Manufacture: Viscoelastic Behavior of the Wood Component

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    Theories of the viscoelastic behavior of amorphous polymers are reviewed and are used to describe the density gradient formation in flakeboard. This technique utilizes measured temperature and gas pressure at discrete locations inside a flake mat during hot pressing to predict the glass transition temperature of wood as a function of press time. The difference between the flake temperature and the predicted glass transition temperature is a relative indicator of the amount of flake deformation and stress relaxation at a location in the mat. A knowledge of the stress history imposed in the mat is then used to relate flake deformation and stress relaxation to the formation of a density gradient. This analysis allows for a significant portion of the density gradient to develop after the hot press has closed. Experimental data for various density gradients support the theories presented here

    A Review Of Creep In Wood: Concepts Relevant To Develop Long-Term Behavior Predictions For Wood Structures

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    A review is presented of the effects of constant and transient moisture and temperature conditions on the time-dependent behavior of wood as a material and as a structural element. A rational approach towards the identification of long-term behavior of wooden structures is proposed. Utilizing the fact that wood is a combination of several polymers, polymer viscoelasticity concepts are suggested to enhance the predictive capabilities. A finite element procedure is outlined to indicate how design predictions can be made. Some attention is given to structures such as domes where creep of the wood could lead to structural instabilities
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