oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 49 )

2018 ( 144 )

2017 ( 130 )

2016 ( 162 )

Custom range...

Search Results: 1 - 10 of 85980 matches for " Bradley W. Frazee "
All listed articles are free for downloading (OA Articles)
Page 1 /85980
Display every page Item
Urine Collection in the Emergency Department: What Really Happens in There?
Bradley W. Frazee,Kenneth Frausto,Bitou Cisse,Douglas E. A. White
Western Journal of Emergency Medicine : Integrating Emergency Care with Population Health , 2012,
Abstract: Introduction: In women with suspected urinary tract infection (UTI), a non-contaminated voidedspecimen is considered important for valid urinalysis and culture results. We assess whethermidstream parted-labia catch (MSPC) instructions were provided by nurses, understood, andperformed correctly, according to the patient.Methods: We conducted a cross-sectional survey of English- and Spanish-speaking female patientssubmitting voided urine samples for urinalysis for suspected UTI. The survey was conducted in apublic teaching hospital emergency department (ED) from June to December 2010, beginning 2months after development and dissemination of a nursing MSPC instructions protocol. Researchassistants administered the survey within 2 hours of urine collection. Nurses were unaware of thestudy purpose.Results: Of 129 patients approached, 74 (57%) consented and were included in the analysis.Median age was 35; 44% were Latino. Regarding instructions from nurses, patients reported thefollowing: 45 (61%; 95% CI 50-72%) received any instructions; of whom 37 (82%; 95% CI 71-93%)understood them completely. Sixteen (36%; 95% CI 22-51%) were instructed to collect midstream;and 7 (16%; 95% CI 6-29%) to part the labia. Regardless of receiving or understanding instructions,33 (45%; 95% CI 33-57%) reported actually collecting midstream, and 11 (15%, 95% CI 8-25%)parting the labia.Conclusion: In this ED, instructions for MSPC urine collection frequently were not given, despite anursing protocol, and patients rarely performed the essential steps. An evidence-based approachto urine testing in the ED that considers urine collection technique, is needed.
Learning Space Spotlight: Fostering Collaboration within Nursing Instruction
Rich Bakken,James Frazee
Journal of Learning Spaces , 2012,
Abstract: Spotlight on Nursing Video Conference Room, San Diego State University.
An Improved Method for Fitting p-Mode Profile Asymmetries
Bradley W. Hindman
Physics , 2011,
Abstract: In a power spectrum of the Sun's acoustic waves, the p modes have distinctly skewed frequency profiles. Furthermore, the asymmetry is observed to have the opposite sign in power spectra made from line-of-sight velocity and continuum intensity. The asymmetry and its reversal in sign has previously been explained using a combination of mechanisms that involve the acoustic source. A localized acoustic source within an acoustic cavity naturally generates asymmetric profiles through wave interference; however, the sign of the asymmetry due to this mechanism is identical for all observables. The reversal of the asymmetry between velocity and intensity observations has been attributed to the visibility of the source itself (i.e., "correlated noise"). In this paper, I will show that asymmetry generated by a localized source can be interpreted as either a wave interference effect in physical space, or a mode interference effect in spectral space. I advocate a new mode-fitting procedure based on this new interpretation, whereby the complex phases of all the modes determine the mode asymmetries. Further, I suggest that information about the acoustic source function is encapsulated in the amplitude of each mode, and present a scheme by which the source function can be obtained from measured mode amplitudes by standard helioseismic inversion techniques.
Observations of Coastally Transitioning West African Mesoscale Convective Systems during NAMMA
Bradley W. Klotz,Paul Kucera
International Journal of Geophysics , 2012, DOI: 10.1155/2012/438706
Abstract: Observations from the NASA 10 cm polarimetric Doppler weather radar (NPOL) were used to examine structure, development, and oceanic transition of West African Mesoscale Convective Systems (MCSs) during the NASA African Monsoon Multidisciplinary Analysis (NAMMA) to determine possible indicators leading to downstream tropical cyclogenesis. Characteristics examined from the NPOL data include echo-top heights, maximum radar reflectivity, height of maximum radar reflectivity, and convective and stratiform coverage areas. Atmospheric radiosondes launched during NAMMA were used to investigate environmental stability characteristics that the MCSs encountered while over land and ocean, respectively. Strengths of African Easterly Waves (AEWs) were examined along with the MCSs in order to improve the analysis of MCS characteristics. Mean structural and environmental characteristics were calculated for systems that produced TCs and for those that did not in order to determine differences between the two types. Echo-top heights were similar between the two types, but maximum reflectivity and height and coverage of intense convection (>50 dBZ) are all larger than for the TC producing cases. Striking differences in environmental conditions related to future TC formation include stronger African Easterly Jet, increased moisture especially at middle and upper levels, and increased stability as the MCSs coastally transition.
Observations of Coastally Transitioning West African Mesoscale Convective Systems during NAMMA
Bradley W. Klotz,Paul Kucera
International Journal of Geophysics , 2012, DOI: 10.1155/2012/438706
Abstract: Observations from the NASA 10?cm polarimetric Doppler weather radar (NPOL) were used to examine structure, development, and oceanic transition of West African Mesoscale Convective Systems (MCSs) during the NASA African Monsoon Multidisciplinary Analysis (NAMMA) to determine possible indicators leading to downstream tropical cyclogenesis. Characteristics examined from the NPOL data include echo-top heights, maximum radar reflectivity, height of maximum radar reflectivity, and convective and stratiform coverage areas. Atmospheric radiosondes launched during NAMMA were used to investigate environmental stability characteristics that the MCSs encountered while over land and ocean, respectively. Strengths of African Easterly Waves (AEWs) were examined along with the MCSs in order to improve the analysis of MCS characteristics. Mean structural and environmental characteristics were calculated for systems that produced TCs and for those that did not in order to determine differences between the two types. Echo-top heights were similar between the two types, but maximum reflectivity and height and coverage of intense convection (>50?dBZ) are all larger than for the TC producing cases. Striking differences in environmental conditions related to future TC formation include stronger African Easterly Jet, increased moisture especially at middle and upper levels, and increased stability as the MCSs coastally transition. 1. Introduction Tropical cyclone (TC) lifecycles vary in duration, location, and human impact, but in general, TCs follow a similar progression from genesis, intensification, maturity to eventual decay. Mature systems often receive much attention due to their potential human impact, but one aspect of the TC lifecycle that remains difficult to predict is genesis. For many cases over the North Atlantic basin, tropical storms and hurricanes form as a direct result of African Easterly Waves (AEWs) and associated Mesoscale Convective Systems (MCSs) moving off the West African coast during the African monsoon season [1, 2]. On average, AEWs that move off the coast are found to produce TCs on the order of 15–20% of the time across the Atlantic basin [1, 3]. While Hopsch et al. [4] found that these numbers are true in the Main Development Region [5–8] during the early and later parts of the tropical cyclone season, they also found that the relationship between TC genesis and AEWs during the peak of the season (late August and September) is as high as 40%. In contrast, Avila [9] mentions that there is no correlation between the number of AEWs and the number
Non-Invasive Brain Stimulation Enhances the Effects of Melodic Intonation Therapy
Bradley W. Vines,Gottfried Schlaug
Frontiers in Psychology , 2011, DOI: 10.3389/fpsyg.2011.00230
Abstract: Research has suggested that a fronto-temporal network in the right hemisphere may be responsible for mediating melodic intonation therapy’s (MIT) positive effects on speech recovery. We investigated the potential for a non-invasive brain stimulation technique, transcranial direct current stimulation (tDCS), to augment the benefits of MIT in patients with non-fluent aphasia by modulating neural activity in the brain during treatment with MIT. The polarity of the current applied to the scalp determines the effects of tDCS on the underlying tissue: anodal-tDCS increases excitability, whereas cathodal tDCS decreases excitability. We applied anodal-tDCS to the posterior inferior frontal gyrus of the right hemisphere, an area that has been shown both to contribute to singing through the mapping of sounds to articulatory actions and to serve as a key region in the process of recovery from aphasia, particularly in patients with large left hemisphere lesions. The stimulation was applied while patients were treated with MIT by a trained therapist. Six patients with moderate to severe non-fluent aphasia underwent three consecutive days of anodal-tDCS + MIT, and an equivalent series of sham-tDCS + MIT. The two treatment series were separated by 1 week, and the order in which the treatments were administered was randomized. Compared to the effects of sham-tDCS + MIT, anodal-tDCS + MIT led to significant improvements in fluency of speech. These results support the hypothesis that, as the brain seeks to reorganize and compensate for damage to left hemisphere language centers, combining anodal-tDCS with MIT may further recovery from post-stroke aphasia by enhancing activity in a right hemisphere sensorimotor network for articulation.
Helioseismic detection of deep meridional flow
Douglas Gough,Bradley W. Hindman
Physics , 2009, DOI: 10.1088/0004-637X/714/1/960
Abstract: Steady meridional flow makes no first-order perturbation to the frequencies of helioseismic normal modes. It does, however, Doppler shift the local wavenumber, thereby distorting the eigenfunctions. For high-degree modes, whose peaks in a power spectrum are blended into continuous ridges, the effect of the distortion is to shift the locations of those ridges. From this blended superposition of modes, one can isolate oppositely directed wave components with the same local horizontal wavenumber and measure a frequency difference which can be safely used to infer the subsurface background flow. But such a procedure fails for the components of the more-deeply-penetrating low-degree modes that are not blended into ridges. Instead, one must analyze the spatial distortions explicitly. With a simple toy model, we illustrate one method by which that might be accomplished by measuring the spatial variation of the oscillation phase. We estimate that by this procedure it might be possible to infer meridional flow deep in the solar convection zone.
Axisymmetric Scattering of p Modes by Thin Magnetic Tubes
Bradley W. Hindman,Rekha Jain
Physics , 2011, DOI: 10.1088/0004-637X/746/1/66
Abstract: We examine the scattering of acoustic p-mode waves from a thin magnetic fibril embedded in a gravitationally stratified atmosphere. The scattering is mediated through the excitation of slow sausage waves on the magnetic tube, and only the scattering of the monopole component of the wavefield is considered. Since such tube waves are not confined by the acoustic cavity and may freely propagate along the field lines removing energy from the acoustic wavefield, the excitation of fibril oscillations is a source of acoustic wave absorption as well as scattering. We compute the mode mixing that is achieved and the absorption coefficients and phase shifts. We find that for thin tubes the mode mixing is weak and the absorption coefficient is small and is a smooth function of frequency over the physically relevant band of observed frequencies. The prominent absorption resonances seen in previous studies of unstratified tubes are absent. Despite the relatively small absorption, the phase shift induced can be surprisingly large, reaching values as high as 15 degree for f modes. Further, the phase shift can be positive or negative depending on the incident mode order and the frequency.
An Interpretation of Flare-Induced and Decayless Coronal-Loop Oscillations as Interference Patterns
Bradley W. Hindman,Rekha Jain
Physics , 2013, DOI: 10.1088/0004-637X/784/2/103
Abstract: We present an alternative model of coronal-loop oscillations which considers that the waves are trapped in a 2D waveguide formed by the entire arcade of field lines. This differs from the standard 1D model which treats the waves as the resonant oscillations of just the visible bundle of field lines. Within the framework of our 2D model, the two types of oscillations that have been observationally identified, flare-induced waves and "decayless" oscillations, can both be attributed to MHD fast waves. The two components of the signal differ only because of the duration and spatial extent of the source that creates them. The flare-induced waves are generated by strong localized sources of short duration, while the decayless background can be excited by a continuous, stochastic source. Further, the oscillatory signal arising from a localized, short-duration source can be interpreted as a pattern of interference fringes produced by waves that have traveled diverse routes of various pathlengths through the waveguide. The resulting amplitude of the fringes slowly decays in time with an inverse square root dependence. The details of the interference pattern depend on the shape of the arcade and the spatial variation of the Alfv\'en speed. The rapid decay of this wave component, which has previously been attributed to physical damping mechanisms that remove energy from resonant oscillations, occurs as a natural consequence of the interference process without the need for local dissipation.
Kink Oscillations of a Curved, Gravitationally Stratified Coronal Loop
Bradley W. Hindman,Rekha Jain
Physics , 2012,
Abstract: Loops of magnetic field in the corona are observed to oscillate and these oscillations have been posited to be the superposition of resonant kink waves. To date, most analyses of these oscillations have concentrated on calculating the frequency shifts that result from spatial variation in the kink wave speed. Further, most have ignored gravity and treated the loop as a straight tube. Here we ignore spatial variation in the wave speed, but self-consistently include the effects of gravity and loop curvature in both the equilibrium loop model and in the wave equation. We model a coronal loop as an isolated, thin, magnetic fibril that is anchored at two points in the photosphere. The equilibrium shape of the loop is determined by a balance between magnetic buoyancy and magnetic tension, which is characterized by a Magnetic Bond Number \epsilon, that is typically small |\epsilon| << 1. This balance produces a loop that has a variable radius of curvature. The resonant kink waves of such a loop come in two polarizations that are decoupled from each other: waves with motion completely within the plane of the loop (normal oscillations) and waves with motions that are completely horizontal, perpendicular to the plane of the loop (binormal oscillations). We solve for the eigensolutions of both polarizations using perturbation theory for small Magnetic Bond Number. For modes of the same order, normal oscillations have smaller eigenfrequencies than binormal oscillations. The additional forces of buoyancy and magnetic tension from the curvature of the loop increase and decrease the mode frequencies, respectively. The ratio of the frequencies of the first overtone to the fundamental mode is modified by the inclusion of buoyancy and curvature. We find that the normal polarization possesses a frequency ratio that exceeds the canonical value of 2, whereas the binormal polarization has a ratio less than 2.
Page 1 /85980
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.