3,683 research outputs found
Procedural Skills Training During Emergency Medicine Residency: Are We Teaching the Right Things?
Objectives: The Residency Review Committee training requirements for emergency medicine residents (EM) are defined by consensus panels, with specific topics abstracted from lists of patient complaints and diagnostic codes. The relevance of specific curricular topics to actual practice has not been studied. We compared residency graduates’ self-assessed preparation during training to importance in practice for a variety of EM procedural skills.Methods: We distributed a web-based survey to all graduates of the Denver Health Residency Program in EM over the past 10 years. The survey addressed: practice type and patient census; years of experience; additional procedural training beyond residency; and confidence, preparation, and importance in practice for 12 procedures (extensor tendon repair, transvenous pacing, lumbar puncture, applanation tonometry, arterial line placement, anoscopy, CT scan interpretation, diagnostic peritoneal lavage, slit lamp usage, ultrasonography, compartment pressure measurement and procedural sedation). For each skill, preparation and importance were measured on four-point Likert scales. We compared mean preparation and importance scores using paired sample t-tests, to identify areas of under- or over-preparation.Results: Seventy-four residency graduates (59% of those eligible) completed the survey. There were significant discrepancies between importance in practice and preparation during residency for eight of the 12 skills. Under-preparation was significant for transvenous pacing, CT scan interpretation, slit lamp examinations and procedural sedation. Over-preparation was significant for extensor tendon repair, arterial line placement, peritoneal lavage and ultrasonography. There were strong correlations (r>0.3) between preparation during residency and confidence for 10 of the 12 procedural skills, suggesting a high degree of internal consistency for the survey.Conclusions: Practicing emergency physicians may be uniquely qualified to identify areas of under- and over-preparation during residency training. There were significant discrepancies between importance in practice and preparation during residency for eight of 12 procedures. There was a strong correlation between confidence and preparation during residency for almost all procedural skills, re-enforcing the tenet that residency training is the primary locus of instruction for clinical procedures.[WestJEM. 2009;10:152-156.
Design of the low-speed NLF(1)-0414F and the high-speed HSNLF(1)-0213 airfoils with high-lift systems
The design and testing of Natural Laminar Flow (NLF) airfoils is examined. The NLF airfoil was designed for low speed, having a low profile drag at high chord Reynolds numbers. The success of the low speed NLF airfoil sparked interest in a high speed NLF airfoil applied to a single engine business jet with an unswept wing. Work was also conducted on the two dimensional flap design. The airfoil was decambered by removing the aft loading, however, high design Mach numbers are possible by increasing the aft loading and reducing the camber overall on the airfoil. This approach would also allow for flatter acceleration regions which are more stabilizing for cross flow disturbances. Sweep could then be used to increase the design Mach number to a higher value also. There would be some degradation of high lift by decambering the airfoil overall, and this aspect would have to be considered in a final design
Spectral and Imaging Diagnostics of Spatially-Extended Turbulent Electron Acceleration and Transport in Solar Flares
Solar flares are efficient particle accelerators with a large fraction of
released magnetic energy (10-50%) converted into energetic particles such as
hard X-ray producing electrons. This energy transfer process is not well
constrained, with competing theories regarding the acceleration mechanism(s),
including MHD turbulence. We perform a detailed parameter study examining how
various properties of the acceleration region, including its spatial extent and
the spatial distribution of turbulence, affect the observed electron
properties, such as those routinely determined from X-ray imaging and
spectroscopy. Here, a time-independent Fokker-Planck equation is used to
describe the acceleration and transport of flare electrons through a coronal
plasma of finite temperature. Motivated by recent non-thermal line broadening
observations that suggested extended regions of turbulence in coronal loops, an
extended turbulent acceleration region is incorporated into the model. We
produce outputs for the density weighted electron flux, a quantity directly
related to observed X-rays, modelled in energy and space from the corona to
chromosphere. We find that by combining several spectral and imaging
diagnostics (such as spectral index differences or ratios, energy or
spatial-dependent flux ratios, and electron depths into the chromosphere) the
acceleration properties, including the timescale and velocity dependence, can
be constrained alongside the spatial properties. Our diagnostics provide a
foundation for constraining the properties of acceleration in an individual
flare from X-ray imaging spectroscopy alone, and can be applied to past,
current and future observations including those from RHESSI and Solar Orbiter.Comment: ApJ Accepte
Geochemistry of Sublacustrine Hydrothermal Deposits in Yellowstone Lake—Hydrothermal Reactions, Stable-Isotope Systematics, Sinter Deposition, and Spire Formation
Geochemical and mineralogical studies of hydrothermal deposits and altered vent muds from the floor of Yellowstone Lake indicate that these features form due to hydrothermal fluid quenching in shallow flow conduits or upon egress into bottom waters. Siliceous precipitates occur as conduits within the uppermost sediments, as tabular deposits that form along sedimentary layers, and as spires as much as 8 m tall that grow upward from crater-like depressions on the lake bottom. These deposits are enriched in As, Cs, Hg, Mo, Sb, Tl, and W.
Variations in major-element geochemistry indicate that subaerial sinters from West Thumb and spire interiors are nearly pure SiO2, whereas sublacustrine conduits are less SiO2 rich and are similar in some cases to normal Yellowstone Lake sediments due to incorporation of sediments into conduit walls. Vent muds, which are hydrothermally altered lake sediments, and some outer conduit walls show pervasive leaching of silica (~63 weight percent silica removal). This hydrothermal leaching process may explain the occurrence of most sublacustrine vents in holes or vent craters, but sediment winnowing by vent fluids may also be an important process in some cases.
Stable-isotope studies indicate that most deposits formed at temperatures between 78°C and 160°C and that vent fluids had oxygen-isotope values of –3.2 to –11.6 per mil, significantly higher than lake waters (–*16.5 per mil). Sulfur-isotope studies indicate that vent waters and lake waters are dominated by sulfur derived from volcanic rocks with δ34S ~ 2.5 per mil.
Geochemical reaction modeling indicates that spires form from upwelling hydrothermal fluids that are saturated with amorphous silica at temperatures 80°–96°C. Reaction calculations suggest that silica precipitation on the lake bottom is initially caused by mixing with cold bottom waters. Once a siliceous carapace is established, more rapid silica precipitation occurs by conductive cooling. Silicification of thermophilic bacteria is a very important process in building spire structures
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Inbound Medical Tourism to Barbados: A Qualitative Examination of Local Lawyers’ Prospective Legal and Regulatory Concerns
Background
Enabled by globalizing processes such as trade liberalization, medical tourism is a practice that involves patients’ intentional travel to privately obtain medical care in another country. Empirical legal research on this issue is limited and seldom based on the perspectives of destination countries receiving medical tourists. We consulted with diverse lawyers from across Barbados to explore their views on the prospective legal and regulatory implications of the developing medical tourism industry in the country.
Methods
We held a focus group in February 2014 in Barbados with lawyers from across the country. Nine lawyers with diverse legal backgrounds participated. Focus group moderators summarized the study objective and engaged participants in identifying the local implications of medical tourism and the anticipated legal and regulatory concerns. The focus group was transcribed verbatim and analyzed thematically.
Results
Five dominant legal and regulatory themes were identified through analysis: (1) liability; (2) immigration law; (3) physician licensing; (4) corporate ownership; and (5) reputational protection.
Conclusions
Two predominant legal and ethical concerns associated with medical tourism in Barbados were raised by participants and are reflected in the literature: the ability of medical tourists to recover medical malpractice for adverse events; and the effects of medical tourism on access to health care in the destination country. However, the participants also identified several topics that have received much less attention in the legal and ethical literature. Overall this analysis reveals that lawyers, at least in Barbados, have an important role to play in the medical tourism sector beyond litigation – particularly in transactional and gatekeeper capacities. It remains to be seen whether these findings are specific to the ecology of Barbados or can be extrapolated to the legal climate of other medical tourism destination countries
X-ray Monitoring of Gravitational Lenses With Chandra
We present \emph{Chandra} monitoring data for six gravitationally lensed
quasars: QJ 01584325, HE 04351223, HE 11041805, SDSS 0924+0219, SDSS
1004+4112, and Q 2237+0305. We detect X-ray microlensing variability in all six
lenses with high confidence. We detect energy dependent microlensing in HE
04351223, SDSS 1004+4112, SDSS 0924+0219 and Q 2237+0305. We present a
detailed spectral analysis for each lens, and find that simple power-law models
plus Gaussian emission lines give good fits to the spectra. We detect intrinsic
spectral variability in two epochs of Q 2237+0305. We detect differential
absorption between images in four lenses. We also detect the \feka\ emission
line in all six lenses, and the Ni XXVII K line in two images of Q
2237+0305. The rest frame equivalent widths of the \feka\ lines are measured to
be 0.4--1.2 keV, significantly higher than those measured in typical active
galactic nuclei of similar X-ray luminosities. This suggests that the \feka\
emission region is more compact or centrally concentrated than the continuum
emission region.Comment: 55 pages, 22 figure
X-ray Nova XTE J1550-564: RXTE Spectral Observations
Excellent coverage of the 1998 outburst of the X-ray Nova XTE J1550-564 was
provided by the Rossi X-ray Timing Explorer. XTE J1550-564 exhibited an intense
(6.8 Crab) flare on 1998 September 19 (UT), making it the brightest new X-ray
source observed with RXTE. We present a spectral analysis utilizing 60
Proportional Counter Array spectra from 2.5-20 keV spanning 71 days, and a
nearly continuous All Sky Monitor light curve. The spectra were fit to a model
including multicolor blackbody disk and power-law components. XTE J1550-564 is
observed in the very high, high/soft, and intermediate canonical outburst
states of Black Hole X-ray Novae.Comment: 14 pages including 1 table and 4 figures, Accepted to ApJ Letter
Phase I dose-escalation and pharmacokinetic study of dasatinib in patients with advanced solid tumors
PURPOSE: To determine the maximum tolerated dose, dose-limiting toxicity (DLT), and recommended phase II dose of dasatinib in metastatic solid tumors refractory to standard therapies or for which no effective standard therapy exists.
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EXPERIMENTAL DESIGN: In this phase I, open-label, dose-escalation study, patients received 35 to 160 mg of dasatinib twice daily in 28-day cycles either every 12 hours for 5 consecutive days followed by 2 nontreatment days every week (5D2) or as continuous, twice-daily (CDD) dosing.
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RESULTS: Sixty-seven patients were treated (5D2, n = 33; CDD, n = 34). The maximum tolerated doses were 120 mg twice daily 5D2 and 70 mg twice daily CDD. DLTs with 160 mg 5D2 were recurrent grade 2 rash, grade 3 lethargy, and one patient with both grade 3 prolonged bleeding time and grade 3 hypocalcemia; DLTs with 120 mg twice daily CDD were grade 3 nausea, grade 3 fatigue, and one patient with both grade 3 rash and grade 2 proteinuria. The most frequent treatment-related toxicities across all doses were nausea, fatigue, lethargy, anorexia, proteinuria, and diarrhea, with infrequent hematologic toxicities. Pharmacokinetic data indicated rapid absorption, dose proportionality, and lack of drug accumulation. Although no objective tumor responses were seen, durable stable disease was observed in 16% of patients.<br></br>
CONCLUSION: Dasatinib was well tolerated in this population, with a safety profile similar to that observed previously in leukemia patients, although with much less hematologic toxicity. Limited, although encouraging, preliminary evidence of clinical activity was observed. Doses of 120 mg twice daily (5D2) or 70 mg twice daily (CDD) are recommended for further studies in patients with solid tumors.<br></br>
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