3,576 research outputs found

    Generation and detection of very high frequency acoustic waves in solids Final report

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    Techniques for generation and detection of very high frequency acoustic waves in solid

    Effects of Patient-Directed Music Intervention on Anxiety and Sedative Exposure in Critically Ill Patients Receiving Mechanical Ventilatory Support: A Randomized Clinical Trial

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    Importance: Alternatives to sedative medications, such as music, may alleviate the anxiety associated with ventilatory support. Objective: To test whether listening to self-initiated patient-directed music (PDM) can reduce anxiety and sedative exposure during ventilatory support in critically ill patients. Design, Setting, and Patients: Randomized clinical trial that enrolled 373 patients from 12 intensive care units (ICUs) at 5 hospitals in the Minneapolis-St Paul, Minnesota, area receiving acute mechanical ventilatory support for respiratory failure between September 2006 and March 2011. Of the patients included in the study, 86% were white, 52% were female, and the mean (SD) age was 59 (14) years. The patients had a mean (SD) Acute Physiology, Age and Chronic Health Evaluation III score of 63 (21.6) and a mean (SD) of 5.7 (6.4) study days. Interventions: Self-initiated PDM (n = 126) with preferred selections tailored by a music therapist whenever desired while receiving ventilatory support, self-initiated use of noise-canceling headphones (NCH; n = 122), or usual care (n = 125). Main Outcomes and Measures: Daily assessments of anxiety (on 100-mm visual analog scale) and 2 aggregate measures of sedative exposure (intensity and frequency). Results: Patients in the PDM group listened to music for a mean (SD) of 79.8 (126) (median [range], 12 [0-796]) minutes/day. Patients in the NCH group wore the noise-abating headphones for a mean (SD) of 34.0 (89.6) (median [range], 0 [0-916]) minutes/day. The mixed-models analysis showed that at any time point, patients in the PDM group had an anxiety score that was 19.5 points lower (95% CI, −32.2 to −6.8) than patients in the usual care group (P = .003). By the fifth study day, anxiety was reduced by 36.5% in PDM patients. The treatment × time interaction showed that PDM significantly reduced both measures of sedative exposure. Compared with usual care, the PDM group had reduced sedation intensity by −0.18 (95% CI, −0.36 to −0.004) points/day (P = .05) and had reduced frequency by −0.21 (95% CI, −0.37 to −0.05) points/day (P = .01). The PDM group had reduced sedation frequency by −0.18 (95% CI, −0.36 to −0.004) points/day vs the NCH group (P = .04). By the fifth study day, the PDM patients received 2 fewer sedative doses (reduction of 38%) and had a reduction of 36% in sedation intensity. Conclusions and Relevance: Among ICU patients receiving acute ventilatory support for respiratory failure, PDM resulted in greater reduction in anxiety compared with usual care, but not compared with NCH. Concurrently, PDM resulted in greater reduction in sedation frequency compared with usual care or NCH, and greater reduction in sedation intensity compared with usual care, but not compared with NCH. Trial Registration: clinicaltrials.gov Identifier: NCT00440700 Critically ill mechanically ventilated patients receive intravenous sedative and analgesic medications to reduce anxiety and promote comfort and ventilator synchrony. These potent medications are often administered at high doses for prolonged periods and are associated with adverse effects such as bradycardia, hypotension, gut dysmotility, immobility, weakness, and delirium.1-3 Despite protocols and sedation assessment tools that guide clinicians, patients still experience significant levels of anxiety.4,5 Unrelieved anxiety and fear are not only unpleasant symptoms that clinicians want to palliate, but increased sympathetic nervous system activity can cause dyspnea and increased myocardial oxygen demand.6 Sustained anxiety and sympathetic nervous system activation can decrease the ability to concentrate, rest, or relax.6,7 Mechanically ventilated patients have little control over pharmacological interventions to relieve anxiety; dosing and frequency of sedative and analgesic medications are controlled by intensive care unit (ICU) clinicians. Interventions are needed that reduce anxiety, actively involve patients, and minimize the use of sedative medications. Nonpharmacological interventions such as relaxing music are effective in reducing anxiety while reducing medication administration.8,9 Music is a powerful distractor that can alter perceived levels of anxiety10 by occupying attention channels in the brain with meaningful, auditory stimuli11 rather than stressful environmental stimuli. Listening to preferred, relaxing music has reduced anxiety in mechanically ventilated patients in limited trials.12-15 It is not known if music can reduce anxiety throughout the course of ventilatory support, or reduce exposure to sedative medications. We evaluated if a patient-directed music (PDM) intervention could reduce anxiety and sedative exposure in ICU patients receiving mechanical ventilation

    Gating NO Release from Nitric Oxide Synthase

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    We have investigated the kinetics of NO escape from Geobacillus stearothermophilus nitric oxide synthase (gsNOS). Previous work indicated that NO release was gated at position 223 in mammalian enzymes; our kinetics experiments include mutants at that position along with measurements on the wild type enzyme. Employing stopped-flow UV–vis methods, reactions were triggered by mixing a reduced enzyme/N-hydroxy-l-arginine complex with an aerated buffer solution. NO release kinetics were obtained for wt NOS and three mutants (H134S, I223V, H134S/I223V). We have confirmed that wt gsNOS has the lowest NO release rate of known NOS enzymes, whether bacterial or mammalian. We also have found that steric clashes at positions 223 and 134 hinder NO escape, as judged by enhanced rates in the single mutants. The empirical rate of NO release from the gsNOS double mutant (H134/I223V) is nearly as rapid as that of the fastest mammalian enzymes, demonstrating that both positions 223 and 134 function as gates for escape of the product diatomic molecule

    Jahn-Teller stabilization of a "polar" metal oxide surface: Fe3O4(001)

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    Using ab initio thermodynamics we compile a phase diagram for the surface of Fe3O4(001) as a function of temperature and oxygen pressures. A hitherto ignored polar termination with octahedral iron and oxygen forming a wave-like structure along the [110]-direction is identified as the lowest energy configuration over a broad range of oxygen gas-phase conditions. This novel geometry is confirmed in a x-ray diffraction analysis. The stabilization of the Fe3O4(001)-surface goes together with dramatic changes in the electronic and magnetic properties, e.g., a halfmetal-to-metal transition.Comment: 4 pages, 4 figure

    Factors Influencing Nurse Sedation Practices with Mechanically Ventilated Patients: A U.S. National Survey

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    Objectives Mechanically ventilated patients commonly receive sedative medications. There is increasing evidence that sedative medications impact on patient outcomes. Nursing behaviour is a key determinant of sedation administration. The purpose of this study was to determine factors that influence nurse sedation administration to mechanically ventilated patients. Methods The Nurse Sedation Practices Scale was mailed to a random sample of 1250 members of the American Association of Critical Care Nurses. Results A response rate of 39% was obtained. Respondents were primarily staff nurses (73%) with a bachelor\u27s degree in nursing (59%) from various intensive care unit (ICU) settings. We limited the analysis to adult ICU practitioners (n = 423). The majority of nurses (81%) agreed that sedation is necessary for patient comfort. Nurse attitudes towards the efficacy of sedation for mechanically ventilated patients was positively correlated with nurses’ report of their sedation practice ( = .28, p \u3c .001) and their intent to administer sedation ( = .58, p \u3c .001). Attitudes did not vary with respect to individual or practice setting characteristics. Conclusion Nurses’ attitudes impact sedation administration practices. Modifying nurses’ attitudes on sedation and the experience of mechanical ventilation may be necessary to change sedation practices with mechanically ventilated patients

    Strain and structure driven complex magnetic ordering of a CoO overlayer on Ir(100)

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    We have investigated the magnetic ordering in the ultrathin c(10×\times2) CoO(111) film supported on Ir(100) on the basis of ab-initio calculations. We find a close relationship between the local structural properties of the oxide film and the induced magnetic order, leading to alternating ferromagnetically and anti-ferromagnetically ordered segments. While the local magnetic order is directly related to the geometric position of the Co atoms, the mismatch between the CoO film and the Ir substrate leads to a complex long-range order of the oxide.Comment: 5 pages, 4 figure

    Differences of Cycling Experiences and Perceptions between E-Bike and Bicycle Users in the United States

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    E-bikes are bicycles that provide pedal-assistance to aid people in cycling. Because of the potential of promoting sustainable transportation, more attention has been focused on the e-bike market. This paper investigates the differences of the cycling experience and perceptions between e-bike and conventional bicycle users, using samples drawn from independent bicycle dealer customers. A total of 806 respondents in the United States took the on-line survey, including 363 e-bike-owning respondents. The results show that e-bikes play a more important role in utilitarian travel, such as commuting and running errands, compared to a conventional bicycle. Conventional bicycle-owning respondents use their bicycles more for recreation and exercise. Also, e-bike owners tend to bike longer distances and take more trips per week. Both e-bike respondents and bicycle respondents stated that improved health was a key factor for cycling, while Millennials and Generation X respondents cycle to save time and improve the environment. Finally, an ordered logit model is proposed for evaluating factors that influence interest in future e-bike ownership. Travel purpose, e-bike familiarity, annual household income, and education level are statistically significant factors in the model. These findings begin to provide insight and a profile of potential new markets for e-bikes in the United States

    Comparison of the McGrath® Series 5 and GlideScope® Ranger with the Macintosh laryngoscope by paramedics

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    <p>Abstract</p> <p>Background</p> <p>Out-of-hospital endotracheal intubation performed by paramedics using the Macintosh blade for direct laryngoscopy is associated with a high incidence of complications. The novel technique of video laryngoscopy has been shown to improve glottic view and intubation success in the operating room. The aim of this study was to compare glottic view, time of intubation and success rate of the McGrath<sup>® </sup>Series 5 and GlideScope<sup>® </sup>Ranger video laryngoscopes with the Macintosh laryngoscope by paramedics.</p> <p>Methods</p> <p>Thirty paramedics performed six intubations in a randomised order with all three laryngoscopes in an airway simulator with a normal airway. Subsequently, every participant performed one intubation attempt with each device in the same manikin with simulated cervical spine rigidity using a cervical collar. Glottic view, time until visualisation of the glottis and time until first ventilation were evaluated.</p> <p>Results</p> <p>Time until first ventilation was equivalent after three intubations in the first scenario. In the scenario with decreased cervical motion, the time until first ventilation was longer using the McGrath<sup>® </sup>compared to the GlideScope<sup>® </sup>and AMacintosh (p < 0.01). The success rate for endotracheal intubation was similar for all three devices. Glottic view was only improved using the McGrath<sup>® </sup>device (p < 0.001) compared to using the Macintosh blade.</p> <p>Conclusions</p> <p>The learning curve for video laryngoscopy in paramedics was steep in this study. However, these data do not support prehospital use of the McGrath<sup>® </sup>and GlideScope<sup>® </sup>devices by paramedics.</p
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