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This Article Corrects: “Effectiveness of a Pediatric Emergency Medicine Curriculum in a Public Tanzanian Referral Hospital”
Bostonia. Volume 13
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
Building a collaborative culture in cardiothoracic operating rooms: Pre and postintervention study protocol for evaluation of the implementation of teamSTEPPS training and the impact on perceived psychological safety
IntroductionThe importance of effective communication, a key component of teamwork, is well recognised in the healthcare setting. Establishing a culture that encourages and empowers team members to speak openly in the cardiothoracic (CT) operating room (OR) is necessary to improve patient safety in this high-risk environment.Methods and analysisThis study will take place at Barnes-Jewish Hospital, an academic hospital in affiliation with Washington University School of Medicine located in the USA. All team members participating in cardiac and thoracic OR cases during this 17-month study period will be identified by the primary surgical staff attending on the OR schedule.TeamSTEPPS (Team Strategies and Tools to Enhance Performance and Patient Safety) training course will be taught to all CT OR staff. Before TeamSTEPPS training, staff will respond to a 39-item questionnaire that includes constructs from the Agency for Healthcare Research and Quality Hospital Survey on Patient Safety Culture, Edmondson’s ‘Measure of psychological safety’ questionnaire, and questionnaires on turnover intentions, job satisfaction and ‘burnout’. The questionnaires will be readministered at 6 and 12 months.The primary outcomes to be assessed include the perceived psychological safety of CT OR team members, the overall effect of TeamSTEPPS on burnout and job satisfaction, and observed turnover rate among the OR nurses. As secondary outcomes, we will be assessing self-reported rates of medical error and near misses in the ORs with a questionnaire at the end of each case.Ethics and disseminationEthics approval is not indicated as this project does not meet the federal definitions of research requiring the oversight of the Institutional Review Board (IRB). Patient health information (PHI) will not be generated during the implementation of this project. Results of the trial will be made accessible to the public when published in a peer-reviewed journal following the completion of the study.</jats:sec
Statistical properties of coronal hole rotation rates: Are they linked to the solar interior?
The present paper discusses results of a statistical study of the
characteristics of coronal hole (CH) rotation in order to find connections to
the internal rotation of the Sun. The goal is to measure CH rotation rates and
study their distribution over latitude and their area sizes. In addition, the
CH rotation rates are compared with the solar photospheric and inner layer
rotational profiles. We study coronal holes observed within latitude
and longitude degrees from the solar disc centre during the time span from the
1 January 2013 to 20 April 2015, which includes the extended peak of solar
cycle 24.We used data created by the Spatial Possibilistic Clustering Algorithm
(SPoCA), which provides the exact location and characterisation of solar
coronal holes using SDO=AIA 193 {\AA} channel images. The CH rotation rates are
measured with four-hour cadence data to track variable positions of the CH
geometric centre. North-south asymmetry was found in the distribution of
coronal holes: about 60 percent were observed in the northern hemisphere and 40
percent were observed in the southern hemisphere. The smallest and largest CHs
were present only at high latitudes. The average sidereal rotation rate for 540
examined CHs is degrees/d. Conclusions. The latitudinal
characteristics of CH rotation do not match any known photospheric rotation
profile. The CH angular velocities exceed the photospheric angular velocities
at latitudes higher than 35-40 degrees. According to our results, the CH
rotation profile perfectly coincides with tachocline and the lower layers of
convection zone at around 0.71 ; this indicates that CHs may be
linked to the solar global magnetic field, which originates in the tachocline
region.Comment: 8 pages, 8 figures, Accepted for publication in A&
Spectroscopic And Computational Studies Of The Laser Photolysis Of Matrix Isolated 1,2-dibromoethanes: Formation And Fate Of The Bromoethyl Radicals
We report experimental and computational studies of the photolysis of atmospherically important 1,2-dibromoethanes (1,2-C(2)X(4)Br(2); X = H, F) in Ar matrixes at 5 K. Using the pulsed deposition method, we find that significant conformational relaxation occurs for 1,2-C(2)H(4)Br(2) (EDB; observed anti/gauche ratio =30:1) but not for 1,2-C(2)F(4)Br(2) (TFEDB; anti/gauche = 3:1), which is traced to a larger barrier to rotation about the C-C bond in the latter. Laser photolysis of matrix-isolated EDB at 220 nm reveals the growth of infrared bands assigned to the gauche conformer and C(2)H(4)-Br(2) charge transfer complex (both as major products), and the C(2)H(4)Br radical and C(2)H(3)Br-HBr complex as minor (trace) products. The presence of the C(2)H(4)-Br(2) complex is confirmed in the UV/visible spectrum, which shows an intense charge transfer band at 237 nm that grows in intensity upon annealing. In contrast to previous reports, our experimental and computational results do not support a bridged structure for the C(2)H(4)Br radical in either the gas phase or matrix environments. We also report on the laser photolysis of matrix-isolated TFEDB at 220 nm. Here, the dominant photoproducts are the anti and gauche conformers of the C(2)F(4)Br radical, the vibrational and electronic spectra of which are characterized here for the first time. The increase in yield of radical for TFEDB vs EDB is consistent with the stronger C-Br bond in the fluoro-substituted radical species. The photochemistry of the C(2)F(4)Br radical following excitation at 266 nm was investigated and found to lead C-Br bond cleavage and formation of C(2)F(4). The implications of this work for the atmospheric and condensed phase photochemistry of the alkyl halides is emphasized
Exploring Aerosols near Clouds with High-Spatial-Resolution Aircraft Remote Sensing During SEAC4RS
Since aerosols are important to our climate system, we seek to observe the variability of aerosol properties within cloud systems. When applied to the satelliteborne Moderateresolution Imaging Spectroradiometer (MODIS), the Dark Target retrieval algorithm provides global aerosol optical depth (AOD; at 0.55 m) in cloudfree scenes. Since MODIS' resolution (500m pixels, 3 or 10km product) is too coarse for studying nearcloud aerosol, we ported the Dark Target algorithm to the highresolution (~50m pixels) enhancedMODIS Airborne Simulator (eMAS), which flew on the highaltitude ER2 during the Studies of Emissions, Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys Airborne Science Campaign over the United States in 2013. We find that even with aggressive cloud screening, the ~0.5km eMAS retrievals show enhanced AOD, especially within 6 km of a detected cloud. To determine the cause of the enhanced AOD, we analyze additional eMAS products (cloud retrievals and degradedresolution AOD), coregistered Cloud Physics Lidar profiles, MODIS aerosol retrievals, and groundbased Aerosol Robotic Network observations. We also define spatial metrics to indicate local cloud distributions near each retrieval and then separate into nearcloud and farfromcloud environments. The comparisons show that low cloud masking is robust, and unscreened thin cirrus would have only a small impact on retrieved AOD. Some of the enhancement is consistent with clearcloud transition zone microphysics such as aerosol swelling. However, 3D radiation interaction between clouds and the surrounding clear air appears to be the primary cause of the high AOD near clouds
Broadband Spectral Investigations of SGR J1550-5418 Bursts
We present the results of our broadband spectral analysis of 42 SGR
J1550-5418 bursts simultaneously detected with the Swift/X-ray Telescope (XRT)
and the Fermi/Gamma-ray Burst Monitor (GBM), during the 2009 January active
episode of the source. The unique spectral and temporal capabilities of the XRT
Windowed Timing mode have allowed us to extend the GBM spectral coverage for
these events down to the X-ray domain (0.5-10 keV). Our earlier analysis of the
GBM data found that the SGR J1550-5418 burst spectra were described equally
well with a Comptonized model or with two blackbody functions; the two models
were statistically indistinguishable. Our new broadband (0.5 - 200 keV)
spectral fits show that, on average, the burst spectra are better described
with two blackbody functions than with the Comptonized model. Thus, our joint
XRT/GBM analysis clearly shows for the first time that the SGR J1550-5418 burst
spectra might naturally be expected to exhibit a more truly thermalized
character, such as a two-blackbody or even a multi-blackbody signal. Using the
Swift and RXTE timing ephemeris for SGR J1550-5418 we construct the
distribution of the XRT burst counts with spin phase and find that it is not
correlated with the persistent X-ray emission pulse phase from SGR J1550-5418.
These results indicate that the burst emitting sites on the neutron star need
not be co-located with hot spots emitting the bulk of the persistent X-ray
emission. Finally, we show that there is a significant pulse phase dependence
of the XRT burst counts, likely demonstrating that the surface magnetic field
of SGR J1550-5418 is not uniform over the emission zone, since it is
anticipated that regions with stronger surface magnetic field could trigger
bursts more efficiently.Comment: accepted for publication in The Astrophysical Journa
Improving the efficiency of electrochemical CO2 reduction using immobilized manganese complexes
Immobilization of [Mn(bpy)(CO)3Br], (1) and [Mn(bpy(tBu)2)(CO)3Br] (2, where (bpy(tBu)2) = 4,4′-di-tert-butyl-2,2′-bipyridine) in Nafion/multi-walled carbon nanotubes (MWCNT) on glassy carbon yielded highly active electrodes for the reduction of CO2 to CO in aqueous solutions at pH 7. Films incorporating 2 have significantly improved selectivity towards CO2, with CO : H2 ∼ 1 at −1.4 V vs. SCE, exceeding that for the previously reported 1/MWCNT/Nafion electrode. Furthermore, we report the synthesis and subsequent electrochemical characterization of two new substituted Mn(i) bipyridine complexes, [Mn(bpy(COOH)2)(CO)3Br] (3) and [Mn(bpy(OH)2)(CO)3Br] (4) (where (bpy(COOH)2) = 4,4′-di-carboxy-2,2′-bipyridine and (bpy(OH)2) = 4,4′-di-hydroxy-2,2′-bipyridine). Both 3 and 4 were found to have some activity towards CO2 in acetonitrile solutions; however once immobilized in Nafion membranes CO2 reduction was found to not occur at significant levels.</p
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A Comparison of Cerebral Spect Abnormalities in Hiv-Positive Homosexual Men with and without Cognitive Impairment
Objective: To determine whether technetium Tc 99m exametazime (HMPAO) single-photon emission computed tomography (SPECT) can distinguish between human immunodeficiency virus (HIV)-positive homosexual men with normal neuropsychologic test results and HIV-positive homosexual men with abnormal neuropsychologic test results. Design: Neurologic, neuropsychologic, magnetic resonance imaging, and Tc 99m HMPAO SPECT examinations were performed on 10 HIV-positive homosexual men without cognitive impairment and five HIV-positive homosexual men with cognitive impairment. Patients: Human immunodeficiency virus—positive homosexual men from New York City were recruited for the study. Main Outcome Measures: Findings on SPECT scans were evaluated qualitatively for focal defects, heterogeneity of the cortical margin, white matter hypoperfusion, and decreased global cortical uptake. All SPECT focal defects were coregistered with magnetic resonance images; SPECT heterogeneity and global cortical uptake were also measured quantitatively. Results: Coregistration with magnetic resonance imaging revealed that 63% of the focal SPECT defects corresponded to brain gyri and 37% corresponded to sulci. There was no significant difference in the frequency of qualitative or quantitative SPECT abnormalities between HIV-positive homosexual men with and without cognitive impairment. However, after examining individual neuropsychologic test factors, impaired motor speed performance was associated with decreased quantitative global cerebral uptake. Conclusions: Qualitative SPECT abnormalities are not increased in frequency in HIV-positive homosexual men with global cognitive impairment compared with those in HIV-positive homosexual men without cognitive impairment. Impaired motor speed performance may be associated with decreased quantitative global cerebral uptake
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