158 research outputs found

    Spectrsocopy of Jet-cooled YCu

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    Journal ArticleOptical spectra of jet-cooled diatomic YCu have been recorded using resonant two-photon ionization spectroscopy in a supersonic expansion of helium. The ground state is shown experimentally to be of 1?+ symmetry, with a measured bond length of re"=2.6197(6) ? and a vibrational frequency of 193.21(24) cm-1 for 89Y63Cu. Five excited electronic states are identified as the [10.2]1?+ state, the [11.8]3IIo+ state, the [12.0]3II, state, the [14.0[I1I state, and, with the help of ab initio theory, the [12.2]1II state. No evidence whatever for participation of the 3d orbitals of copper in the chemical bonding is found, and the electronic structure of YCu is found to exhibit a striking similarity to that of YH

    Spectroscopy of mixed early-late transition metal diatomics: ScNi, YPd, and ZrCo

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    Journal ArticleResonant two-photon ionization spectroscopy has been employed to investigate the spectra of the jet-cooled transition metal diatomics ScNi, YPd, and ZrCo, which are isovalent species which possess ~or are thought to possess! an X 2?+ ground state. Several electronic band systems have been observed for these species in the near infrared, and the analysis of these systems is reported. Ground state vibrational intervals of ?G"1/2=334.5 ? 1.0, 264.4?0.2, and 357.7 cm-1 have been determined for ScNi, YPd, and ZrCo, respectively. The spectroscopic results obtained for ScNi and YPd are compared to theoretical calculations performed by other researchers, and a discussion of the chemical bonding in these species is presented

    Obstructive sleep apnea as an independent predictor of postoperative delirium and pain: Protocol for an observational study of a surgical cohort [version 2; referees: 2 approved]

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    Introduction: Postoperative delirium and pain are common complications in adults, and are difficult both to prevent and treat. Obstructive sleep apnea (OSA) is prevalent in surgical patients, and has been suggested to be a risk factor for postoperative delirium and pain. OSA also might impact pain perception, and alter pain medication requirements. This protocol describes an observational study, with the primary aim of testing whether OSA is an independent predictor of postoperative complications, focusing on (i) postoperative incident delirium and (ii) acute postoperative pain severity. We secondarily hypothesize that compliance with prescribed treatment for OSA (typically continuous positive airway pressure or CPAP) might decrease the risk of delirium and the severity of pain. Methods and analysis: We will include data from patients who have been enrolled into three prospective studies: ENGAGES, PODCAST, and SATISFY-SOS. All participants underwent general anesthesia for a non-neurosurgical inpatient operation, and had a postoperative hospital stay of at least one day at Barnes Jewish Hospital in St. Louis, Missouri, from February 2013 to May 2018.  Patients included in this study have been assessed for postoperative delirium and pain severity as part of the parent studies. In the current study, determination of delirium diagnosis will be based on the Confusion Assessment Method, and the Visual Analogue Pain Scale will be used for pain severity. Data on OSA diagnosis, OSA risk and compliance with treatment will be obtained from the preoperative assessment record. Other variables that are candidate risk factors for delirium and pain will also be extracted from this record. We will use logistic regression to test whether OSA independently predicts postoperative delirium and linear regression to assess OSAs relationship to acute pain severity. We will conduct secondary analyses with subgroups to explore whether these relationships are modified by compliance with OSA treatment.</ns4:p

    Perceptions of School and Health Department Emergency Preparedness Collaboration

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    Background: School systems often have the vital responsibility of protecting students during emergency situations. Collaborations with the local health department (LHD) can be invaluable in helping schools effectively fulfill this responsibility. Purpose: An evaluation of existing organizational collaborations is needed to describe attitudes toward current efforts and to form recommendations for enhancing the effectiveness of future joint programs. Methods: Questionnaires regarding perceptions of existing collaborations were distributed to a sample of LHDs and schools districts in spring and summer 2011. Participant responses from each organization were paired on jurisdictional area, forming 25 paired observations. Analyses were conducted in early 2012. Descriptive statistics of selected variables were computed and differences between paired LHD and school district responses were analyzed. Results: Results showed that school districts and LHDs both rated engagement between organizations in emergency preparedness as extremely important. Each gave high ratings on success and satisfaction of current efforts. Organizations had significant differences in ratings measuring their agreement with specific collaboration drawbacks. Implications: These results suggest the potential for extended and enhanced collaborations, although future programs might be most effectively implemented when tailored to limit the perceived drawbacks of individual organizations. Continued and improved collaborations between school districts and their local health departments will help to increase the school systems’ abilities to adequately prepare for and respond to the needs of the children they serve in the event of an emergency

    Status of the NEXT Ion Thruster Long Duration Test

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    The status of NASA's Evolutionary Xenon Thruster (NEXT) Long Duration Test (LDT) is presented. The test will be conducted with a 36 cm diameter engineering model ion thruster, designated EM3, to validate and qualify the NEXT thruster propellant throughput capability of 450 kg xenon. The ion thruster will be operated at various input powers from the NEXT throttle table. Pretest performance assessments demonstrated that EM3 satisfies all thruster performance requirements. As of June 26, 2005, the ion thruster has accumulated 493 hours of operation and processed 10.2 kg of xenon at a thruster input power of 6.9 kW. Overall ion thruster performance, which includes thrust, thruster input power, specific impulse, and thrust efficiency, has been steady to date with very little variation in performance parameters

    Testing of a Liquid Oxygen/Liquid Methane Reaction Control Thruster in a New Altitude Rocket Engine Test Facility

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    A relocated rocket engine test facility, the Altitude Combustion Stand (ACS), was activated in 2009 at the NASA Glenn Research Center. This facility has the capability to test with a variety of propellants and up to a thrust level of 2000 lbf (8.9 kN) with precise measurement of propellant conditions, propellant flow rates, thrust and altitude conditions. These measurements enable accurate determination of a thruster and/or nozzle s altitude performance for both technology development and flight qualification purposes. In addition the facility was designed to enable efficient test operations to control costs for technology and advanced development projects. A liquid oxygen-liquid methane technology development test program was conducted in the ACS from the fall of 2009 to the fall of 2010. Three test phases were conducted investigating different operational modes and in addition, the project required the complexity of controlling propellant inlet temperatures over an extremely wide range. Despite the challenges of a unique propellant (liquid methane) and wide operating conditions, the facility performed well and delivered up to 24 hot fire tests in a single test day. The resulting data validated the feasibility of utilizing this propellant combination for future deep space applications

    Fluency Assistance Device

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    Currently about 1% of the world population (~70 million people) have a stutter considered a fluency disorder. Some fluency assistance devices are available for this population, but most are highly expensive or unreliable. Fluency Assistance Device (FAD) seeks to assist a niche community of these individuals for whom therapy has been unsuccessful but are currently depending on a device originally known as the Edinburgh Masker. FAD aims to redesign the masker to be more comfortable for the end user. FAD is developing versions 1.1 and 2.0 of the improved masker. Version 1.1 will update the original masker circuitry with surface mount devices. This will allow a slimmer circuitry enclosure, and enable upgrades of the original as requested. Version 2.0 will use Bluetooth technology and a microcontroller to achieve masker functionality with software code. FAD is now finalizing Version 1.1 and beginning Version 2.0.https://mosaic.messiah.edu/engr2020/1008/thumbnail.jp

    Gender differences in health-related quality of life of adolescents with cystic fibrosis

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    BACKGROUND: Female patients with cystic fibrosis (CF) have consistently poorer survival rates than males across all ages. To determine if gender differences exist in health-related quality of life (HRQOL) of adolescent patients with CF, we performed a cross-section analysis of CF patients recruited from 2 medical centers in 2 cities during 1997–2001. METHODS: We used the 87-item child self-report form of the Child Health Questionnaire to measure 12 health domains. Data was also collected on age and forced expiratory volume in 1 second (FEV(1)). We analyzed data from 98 subjects and performed univariate analyses and linear regression or ordinal logistic regression for multivariable analyses. RESULTS: The mean (SD) age was 14.6 (2.5) years; 50 (51.0%) were female; and mean FEV(1 )was 71.6% (25.6%) of predicted. There were no statistically significant gender differences in age or FEV(1). In univariate analyses, females reported significantly poorer HRQOL in 5 of the 12 domains. In multivariable analyses controlling for FEV(1 )and age, we found that female gender was associated with significantly lower global health (p < 0.05), mental health (p < 0.01), and general health perceptions (p < 0.05) scores. CONCLUSION: Further research will need to focus on the causes of these differences in HRQOL and on potential interventions to improve HRQOL of adolescent patients with CF
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