338 research outputs found
Nonsolar astronomy with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI)
The Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) is a NASA Small Explorer satellite designed to study hard x-ray and gamma-ray emission from solar flares. In addition, its high-resolution array of germanium detectors can see photons from high-energy sources throughout the Universe. Here we discuss the various algorithms necessary to extract spectra, lightcurves, and other information about cosmic gamma-ray bursts, pulsars, and other astrophysical phenomena using an unpointed, spinning array of detectors. We show some preliminary results and discuss our plans for future analyses. All RHESSI data are public, and scientists interested in participating should contact the principal author
Hard Burst Emission from the Soft Gamma Repeater SGR 1900+14
We present evidence for burst emission from SGR 1900+14 with a power-law high
energy spectrum extending beyond 500 keV. Unlike previous detections of high
energy photons during bursts from SGRs, these emissions are not associated with
high-luminosity burst intervals. Not only is the emission hard, but the spectra
are better fit by Band's GRB function rather than by the traditional
optically-thin thermal bremsstrahlung model. We find that the spectral
evolution within these hard events obeys a hardness/intensity anti-correlation.
Temporally, these events are distinct from typical SGR burst emissions in that
they are longer (~ 1 s) and have relatively smooth profiles. Despite a
difference in peak luminosity of > 1E+11 between these bursts from SGR 1900+14
and cosmological GRBs, there are striking temporal and spectral similarities
between the two kinds of bursts, aside from spectral evolution. We outline an
interpretation of these events in the context of the magnetar model.Comment: 11 pages (text and figures), submitted to ApJ Letters, corrected
erroneous hardness ratio
Information Needs and Requirements for Decision Support in Primary Care: An Analysis of Chronic Pain Care
Decision support system designs often do not align with the information environments in which clinicians work. These work environments may increase Clinicians’ cognitive workload and harm their decision making. The objective of this study was to identify information needs and decision support requirements for assessing, diagnosing, and treating chronic noncancer pain in primary care. We conducted a qualitative study involving 30 interviews with 10 primary care clinicians and a subsequent multidisciplinary systems design workshop. Our analysis identified four key decision requirements, eight clinical information needs, and four decision support design seeds. Our findings indicate that clinicians caring for chronic pain need decision support that aggregates many disparate information elements and helps them navigate and contextualize that information. By attending to the needs identified in this study, decision support designers may improve Clinicians’ efficiency, reduce mental workload, and positively affect patient care quality and outcomes
Statistical properties of SGR 1900+14 bursts
We study the statistics of soft gamma repeater (SGR) bursts, using a data
base of 187 events detected with BATSE and 837 events detected with RXTE PCA,
all from SGR 1900+14 during its 1998-1999 active phase. We find that the
fluence or energy distribution of bursts is consistent with a power law of
index 1.66, over 4 orders of magnitude. This scale-free distribution resembles
the Gutenberg-Richter Law for earthquakes, and gives evidence for
self-organized criticality in SGRs. The distribution of time intervals between
successive bursts from SGR 1900+14 is consistent with a log-normal
distribution. There is no correlation between burst intensity and the waiting
times till the next burst, but there is some evidence for a correlation between
burst intensity and the time elapsed since the previous burst. We also find a
correlation between the duration and the energy of the bursts, but with
significant scatter. In all these statistical properties, SGR bursts resemble
earthquakes and solar flares more closely than they resemble any known
accretion-powered or nuclear-powered phenomena. Thus our analysis lends support
to the hypothesis that the energy source for SGR bursts is internal to the
neutron star, and plausibly magnetic.Comment: 11 pages, 4 figures, accepted for publication in ApJ
The Effect of EHR-Integrated Patient Reported Outcomes on Satisfaction with Chronic Pain Care
Objective
Given its complexity, chronic noncancer pain presents an opportunity to use health information technology (IT) to improve care experiences. The objective of this study was to assess whether integrating patient-reported outcomes (PRO) data in an electronic health record (EHR) affects providers and patient satisfaction with chronic noncancer pain care.
Study Design
We conducted a pragmatic cluster randomized trial involving four family medicine clinics.
Methods
We enrolled primary care providers (PCPs) and their patients with chronic noncancer pain. In the first seven months (education phase), PCPs in intervention practices received education on how to use PROs for pain care. In the second seven months (PRO phase), patients in intervention practices reported pain-related outcomes upon arrival at their visits. PROs were immediately reported to PCPs through the EHR. Control group PCPs provided usual care. We compared intervention and control practices in terms of provider and patient satisfaction with care.
Results
During the education phase, patients’ mean ratings of their visits did not differ between control and intervention (9.33 vs. 9.08, p=0.20). During the PRO phase, patients’ mean ratings did not differ between control and intervention (9.28 vs 9.01, p=0.20). Similarly, there were no differences between the intervention and control groups in terms of provider satisfaction.
Conclusion
Delivering EHR-integrated PROs did not consistently improve patient or provider satisfaction. Positively, we found no evidence that the PRO tools negatively affected satisfaction. Future studies and technological innovations are needed to translate point-of-care health IT tools to improvements in patient and provider experiences
An Analysis of Primary Care Clinician Communication About Risk, Benefits, and Goals Related to Chronic Opioid Therapy
Background. Safe opioid prescribing and effective pain care are particularly important issues in the United States, where decades of widespread opioid prescribing have contributed to high rates of opioid use disorder. Because of the importance of clinician-patient communication in effective pain care and recent initiatives to curb rising opioid overdose deaths, this study sought to understand how clinicians and patients communicate about the risks, benefits, and goals of opioid therapy during primary care visits. Methods. We recruited clinicians and patients from six primary care clinics across three health systems in the Midwest United States. We audio-recorded 30 unique patients currently receiving opioids for chronic noncancer pain from 12 clinicians. We systematically analyzed transcribed, clinic visits to identify emergent themes. Results. Twenty of the 30 patient participants were females. Several patients had multiple pain diagnoses, with the most common diagnoses being osteoarthritis (n = 10), spondylosis (n = 6), and low back pain (n = 5). We identified five themes: 1) communication about individual-level and population-level risks, 2) communication about policies or clinical guidelines related to opioids, 3) communication about the limited effectiveness of opioids for chronic pain conditions, 4) communication about nonopioid therapies for chronic pain, and 5) communication about the goal of the opioid tapering. Conclusions. Clinicians discuss opioid-related risks in varying ways during patient visits, which may differentially affect patient experiences. Our findings may inform the development and use of more standardized approaches to discussing opioids during primary care visits
Accuracy and Precision of Age Estimates for Pallid Sturgeon from Pectoral Fin Rays
Accurate age information is critical to the biological understanding and management of most fish species, but particularly for species of concern, such as the pallid sturgeon Scaphirhynchus albus. The accuracy and precision of pallid sturgeon age estimates from pectoral fin ray sections has never been established, yet all accumulated age information for the species was collected using this technique. To examine the accuracy and precision of age estimates, 16 pectoral fin ray samples from age-6 pallid sturgeon were obtained from Gavins Point National Fish Hatchery, South Dakota. The fin rays were sectioned, mounted, and independently examined twice by each of two readers. Only 28.1% of the age estimates accurately reflected the known age of the fish. Multiple readings of the same sample by the same reader (within-reader precision) only agreed 25% of the time, differences being as great as 5 years between the two estimates. Between-reader agreement was 46.9%, the two readers\u27 estimates of the same fish differing by as much as 2 years. Because of low accuracy and precision, estimated ages from pallid sturgeon pectoral fin rays should be viewed with caution
Why Acute Ischemic Stroke Patients in the United States Use or Do Not Use Emergency Medical Services Transport? Findings of an Inpatient Survey
Background
Patients with acute ischemic stroke (AIS) who use emergency medical services (EMS) receive quicker reperfusion treatment which, in turn, mitigates post-stroke disability. However, nationally only 59% use EMS. We examined why AIS patients use or do not use EMS.
Methods
During 2016–2018, a convenience sample of AIS patients admitted to a primary stroke center in South Carolina were surveyed during hospitalization if they were medically fit, available for survey when contacted, and consented to participate. The survey was programed into EpiInfo with skip patterns to minimize survey burden and self-administered on a touchscreen computer. Survey questions covered symptom characteristics, knowledge of stroke and EMS importance, subjective reactions, role of bystanders and financial factors. Descriptive and multiple regression analyses were performed.
Results
Of 108 inpatients surveyed (out of 1179 AIS admissions), 49% were male, 44% African American, mean age 63.5 years, 59% mild strokes, 75 (69%) arrived by EMS, 33% were unaware of any stroke symptom prior to stroke, and 75% were unaware of the importance of EMS use for good outcome. Significant factors that influenced EMS use decisions (identified by regression analysis adjusting for stroke severity) were: prior familiarity with stroke (self or family/friend with stroke) adjusted odds ratio, 5.0 (95% confidence interval, 1.6, 15.1), perceiving symptoms as relevant for self and indicating possible stroke, 26.3 (7.6, 91.1), and bystander discouragement to call 911, 0.1 (0.01,0.7). Further, all 27 patients who knew the importance of EMS had used EMS. All patients whose physician office advised actions other than calling EMS at symptom onset, did not use EMS.
Conclusion
Systematic stroke education of patients with stroke-relevant comorbidities and life-style risk factors, and public health educational programs may increase EMS use and mitigate post-stroke disability
Cyclone Hard X-Ray Observatory
In response to the recent NASA-SMEX Announcement of Opportunity, our collaboration proposed Cyclone, the Cyclotron/Nuclear Explorer. Cyclone is a broadband pointed astrophysical observatory, combining the highest spectral resolutions (E/(Delta) E approximately 30 - 300) and angular resolutions (15') achieved in the optimized hard X-ray range (10 - 200 keV). The instrument consists of 19 co-aligned rotation modulation collimator (RMC) telescopes, each with a high spectral resolution, 6-cm diameter germanium detector (GeD) covering energies from 3 keV to 600 keV. Both the optics and detectors are actively shielded with 15-mm BGO to gain low background an high sensitivity to astrophysical sources. A 550-km altitude, circular equatorial orbit also minimizes background. Building strongly upon instrumental heritage from the High-Energy Solar Spectroscopic Imager (HESSI) program, Cyclone would be ready for launch by September 2003. The instrument design and expected performance are discussed, as well as a brief overview of scientific goals
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