3,785 research outputs found
Performance of emergency physicians utilizing a video-assisted semi-rigid fiberoptic stylet for intubation of a difficult airway in a high-fidelity simulated patient: a pilot study
BACKGROUND: This study was designed to evaluate emergency physician success and satisfaction using a video-assisted semi-rigid fiberoptic stylet, the Clarus Video System (CVS), during a simulated difficult airway scenario. FINDINGS: Emergency physicians (EPs) of all levels were first shown a brief slide show and three example videos, and then given 20 min to practice intubating a mannequin using both the CVS and standard direct laryngoscopy (DL). The mannequin was then placed in a c-collar and set to simulate an apneic patient with an edematous tongue and trismus. Each EP was given up to three timed attempts with each technique. They rated their satisfaction with the CVS, usefulness for their practice, and the effectiveness of the tutorial. Direct laryngoscopy had a 65% success rate on the first attempt, 20% on the second, and 15% required three or more. The CVS had a 100% success rate with a single attempt. Average time for independent DL attempts was 43.41 s (SD = ±26.82) and 38.71 s (SD = ±34.14) with CVS. Cumulative attempt times were analyzed and compared (DL = 74.55 ± 68.40 s and CVS = 38.71 ± 34.14 s; p = 0.028). EPs rated their satisfaction with, and usefulness of, the CVS as ≥6 out of 10. CONCLUSION: Emergency physicians were able to successfully intubate a simulated difficult airway model on the first attempt 100% of the time. Emergency physicians were satisfied with the CVS and felt that it would be useful in their practice
Neutron Stars in f(R) Gravity with Perturbative Constraints
We study the structure of neutron stars in f(R) gravity theories with
perturbative constraints. We derive the modified Tolman-Oppenheimer-Volkov
equations and solve them for a polytropic equation of state. We investigate the
resulting modifications to the masses and radii of neutron stars and show that
observations of surface phenomena alone cannot break the degeneracy between
altering the theory of gravity versus choosing a different equation of state of
neutron-star matter. On the other hand, observations of neutron-star cooling,
which depends on the density of matter at the stellar interior, can place
significant constraints on the parameters of the theory.Comment: Discussion extended, typos corrected, figures revised. Accepted for
publication in PR
Meningeal carcinomatosis diagnosed during stroke evaluation in the emergency department
A 70-year-old female presented to the emergency department with a 3-day history of intermittent dysphasia and right facial droop. Computed tomography (CT) and magnetic resonance imaging (MRI) were obtained, and the patient was found to have meningeal carcinomatosis, also known as leptomeningeal metastases. Meningeal carcinomatosis is a rare metastatic complication of some solid tumors and hematopoietic neoplasms, and has a median survival rate of 2.4 months. The role of the emergency physician is to appropriately diagnose this condition, treat emergent side effects, provide symptomatic relief, and ensure multi-disciplinary management
Exploring alternative approaches to entrepreneurial exporting: internationalization through an effectual lens
In 2017 EU exports supported 36 million jobs in the EU. Furthermore, it was estimated that on average each billion euro of extra-EU exports supported more than 13,000 jobs in the EU Exporting is widely viewed as one of the key drivers of economic growth and many traditional approaches have been applied to engender greater levels of exporting by indigenous enterprises. However, Sarasvathy [(2001). Causation and effectuation: Toward a theoretical shift from economic inevitability to entrepreneurial contingency. Academy of Management Review, 26, 243–263, (2013). An effectual approach to international entrepreneurship: Overlaps, challenges and provocative possibilities. The Journal of Entrepreneurship Theory and Practice, 71–95] on ‘Effectuation’ suggests that an alternative approach to achieving entrepreneurial growth might be possible. This article seeks to address a gap in existing literature regarding the relationship between exporting and effectuation
Analyzing large-scale conservation interventions with Bayesian hierarchical models: a case study of supplementing threatened Pacific salmon.
Myriad human activities increasingly threaten the existence of many species. A variety of conservation interventions such as habitat restoration, protected areas, and captive breeding have been used to prevent extinctions. Evaluating the effectiveness of these interventions requires appropriate statistical methods, given the quantity and quality of available data. Historically, analysis of variance has been used with some form of predetermined before-after control-impact design to estimate the effects of large-scale experiments or conservation interventions. However, ad hoc retrospective study designs or the presence of random effects at multiple scales may preclude the use of these tools. We evaluated the effects of a large-scale supplementation program on the density of adult Chinook salmon Oncorhynchus tshawytscha from the Snake River basin in the northwestern United States currently listed under the U.S. Endangered Species Act. We analyzed 43 years of data from 22 populations, accounting for random effects across time and space using a form of Bayesian hierarchical time-series model common in analyses of financial markets. We found that varying degrees of supplementation over a period of 25 years increased the density of natural-origin adults, on average, by 0-8% relative to nonsupplementation years. Thirty-nine of the 43 year effects were at least two times larger in magnitude than the mean supplementation effect, suggesting common environmental variables play a more important role in driving interannual variability in adult density. Additional residual variation in density varied considerably across the region, but there was no systematic difference between supplemented and reference populations. Our results demonstrate the power of hierarchical Bayesian models to detect the diffuse effects of management interventions and to quantitatively describe the variability of intervention success. Nevertheless, our study could not address whether ecological factors (e.g., competition) were more important than genetic considerations (e.g., inbreeding depression) in determining the response to supplementation
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