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Introduction: Quality improvement and patient safety (QIPS) are increasingly recognized as integral to the provision and advancement of emergency medicine (EM) care. In 2015, QIPS were added to the Canadian Medical Education Directives for Specialists (CanMEDS) framework. However, the level of QIPS education and support that Canadian EM residents receive is unknown. In order to better plan national QIPS efforts aimed at enabling EM residents to improve their local care settings, we sought to assess the current state of QIPS education and support in Canadian EM residency programs. Methods: This was a descriptive, cross-sectional electronic survey that was disseminated to all current Canadian EM residents from both Royal College (RC) and Family Medicine - EM training streams. Residents were recruited either directly or through their program's administrative assistant. The survey consisted of multiple-choice, Likert and free-text entry questions. Themes included a) familiarity with QIPS; b) local opportunities for QIPS projects and mentorship; and c) desire for further QIPS education and involvement. The survey was open for a five-week period, with formal reminders after the first and third weeks. Descriptive statistics are reported. Results: 189 (35%) of 535 current EM residents completed the survey, representing all 17 medical schools. 77% of respondents were from the RC stream. 54.7% of respondents reported being “somewhat” or “very” familiar with QIPS. 47.2% of respondents reported “not knowing” or “not having readily available” QIPS projects to participate in their local environment, and 51.5% had equivalent responses with respect to QIPS mentorship opportunities. Only 17.5% of respondents reported that QIPS methodologies were already formally taught in their residency program, and 66.9% indicated a desire for increased QIPS teaching. The majority of respondents were “slightly” (35.9%), “moderately” (23.2%) or “very” (11.3%) interested in becoming involved with QIPS training and initiatives. Conclusion: Responding Canadian EM residents are interested in obtaining greater QIPS education as well as project and mentorship opportunities, but many perceive that they do not have adequate access to these at the current time. As the importance of QIPS increases in the EM community, supporting residents with more robust educational infrastructures may be necessary. Future efforts may include the standardizing of QIPS postgraduate curricula and improving access to QIPS opportunities across the country.
The second Singapore Mental Health Study (SMHS) – a nationwide, cross-sectional, epidemiological survey - was initiated in 2016 with the intent of tracking the state of mental health of the general population in Singapore. The study employed the same methodology as the first survey initiated in 2010. The SMHS 2016 aimed to (i) establish the 12-month and lifetime prevalence and correlates of major depressive disorder (MDD), dysthymia, bipolar disorder, generalised anxiety disorder (GAD), obsessive compulsive disorder (OCD) and alcohol use disorder (AUD) (which included alcohol abuse and dependence) and (ii) compare the prevalence of these disorders with reference to data from the SMHS 2010.
Door-to-door household surveys were conducted with adult Singapore residents aged 18 years and above from 2016 to 2018 (n = 6126) which yielded a response rate of 69.0%. The subjects were randomly selected using a disproportionate stratified sampling method and assessed using World Health Organization Composite International Diagnostic Interview version 3.0 (WHO-CIDI 3.0). The diagnoses of lifetime and 12-month selected mental disorders including MDD, dysthymia, bipolar disorder, GAD, OCD, and AUD (alcohol abuse and alcohol dependence), were based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria.
The lifetime prevalence of at least one mood, anxiety or alcohol use disorder was 13.9% in the adult population. MDD had the highest lifetime prevalence (6.3%) followed by alcohol abuse (4.1%). The 12-month prevalence of any DSM-IV mental disorders was 6.5%. OCD had the highest 12-month prevalence (2.9%) followed by MDD (2.3%). Lifetime and 12-month prevalence of mental disorders assessed in SMHS 2016 (13.8% and 6.4%) was significantly higher than that in SMHS 2010 (12.0% and 4.4%). A significant increase was observed in the prevalence of lifetime GAD (0.9% to 1.6%) and alcohol abuse (3.1% to 4.1%). The 12-month prevalence of GAD (0.8% vs. 0.4%) and OCD (2.9% vs. 1.1%) was significantly higher in SMHS 2016 as compared to SMHS 2010.
The high prevalence of OCD and the increase across the two surveys needs to be tackled at a population level both in terms of creating awareness of the disorder and the need for early treatment. Youth emerge as a vulnerable group who are more likely to be associated with mental disorders and thus targeted interventions in this group with a focus on youth friendly and accessible care centres may lead to earlier detection and treatment of mental disorders.
We construct a parameterized function which describes the possible dependence of planetary nebulae formation upon metal abundance and stellar mass. Data on galaxies in the local group compared with predictions made from the parameterized function indicate that heavy element abundance is the principal agent influencing the formation of planetary nebulae; stars which are rich in heavy elements are the progenitors of planetary nebulae. Our analysis, when compared with the observations, argues for a modest degree of pre-enrichment in a few of the sample galaxies. The heavy element dependence of planetary nebulae formation also accounts for the deficit of planetary nebulae in the nuclei of NGC 221 and NGC 224, and in the bulge of our galaxy.
Ice motion over Lake Vostok, Antarctica, is measured using repeat-pass synthetic-aperture radar (SAR) interferometry. The coverage of the lake and the components of the vector field are resolved using 10 overlapping data takes from ascending and descending look directions. Seventy-day temporal baselines provide the sensitivity required to observe the range of ice motion (0–6 m a−1) over the lake and the adjacent ice sheet. It is remarkable that the scattering field remained coherent over these time separations. This is critical for interferometric analysis and can be attributed to the low surface accumulation and low air temperature at this elevation. The regional flow of the ice sheet around Lake Vostok is from west to east, perpendicular to the surface elevation contours. As the ice flows past the grounding line, a southward component of motion develops that is correlated with the north–south surface slope along the length of the lake. The surface velocity increases slowly from the northern tip of the lake and then more rapidly south of 77° S. At Vostok station, the ice motion is 4.2 m a−1. Across the lake and away from boundary effects, the down-lake flow pattern takes on a parabolic profile with maximum velocity close to the center line of the lake. The overall influence of the subglacial lake is the addition of a down-lake motion component to the prevailing west–east motion of the ice sheet. As a result, we estimate 10% of the mass flowing onto the lake is diverted south. Reconstructions based on the Vostok ice core indicate that the ice was grounded up-glacier from the core site approximately 5000 years ago. This suggests a minimum freezing rate of 40 mm a−1 for the subglacial accretion ice, 10 times greater than that inferred from thermodynamic modeling of the upper 2 km of the ice core.
Observations of sea-ice thickness and kinematics are essential for understanding changes in sea-ice mass balance, interactions between the ice cover and the ocean and atmosphere and for improving projections of sea-ice response in a warming climate. These parameters are not directly observable with current sensor technology, but are derived from satellite altimetry and imagery. While there is progress in the retrievals of Arctic sea-ice thickness from satellite altimetry, approaches to address Southern Ocean ice thickness require additional attention. On the other hand, procedures to derive sea-ice motion from satellite imagery are more mature and better understood and have been employed to produce useful results for more than a decade. Adequate sampling of sub-daily ice motion, however, remains a challenge. Generally, satellite instruments provide large-scale coverage but the frequency of temporal sampling is limited by orbit characteristics. In this review, I focus on the approaches, uncertainties, sampling limitations and validation issues associated with the estimation of sea-ice thickness and motion. I provide a summary of current and anticipated capabilities for monitoring sea-ice thickness and kinematics from space. The prospects for continuing these measurements into the next decade, from a satellite remote-sensing perspective, are discussed.
Snowmelt regions on Greenland ice are mapped daily with the SeaWinds wideswath Ku-band (13.4 GHz) scatterometer on the QuikSCAT satellite. The approach exploits the high temporal resolution of SeaWinds/QuikSCAT data for the melt mapping using diurnal backscatter change independent of the absolute calibration. The results reveal several pronounced melting and refreezing events, and effects of topography are evident in the melt patterns. The spatial resolution is sufficient to identify melt features on the Sukker-toppen Iskappe west of the main ice sheet. An anomalous warming event, caused by down-ward mixing of warm air, is detected in late September 1999 over the west flank of the southern Greenland ice sheet. Time-series images of melt regions are presented over the period from summer to the fall freeze-up. The satellite observations are verified with in situ measurements from the Greenland Climate Network stations.
An unidentified emission feature at 21 μm has been detected in the IRAS Low Resolution Spectra (LRS) of 5 IRAS sources (Kwok, Volk, and Hrivnak 1989, Hrivnak and Kwok 1991). The sources are generally found to be F and G supergiants with cool, detached dust shells. We have searched for additional 21 μm sources in the LRS database and have obtained ground-based UKIRT spectra at 10 and 20 μm in an attempt to confirm the LRS feature.
Arctic snow depth data products from four years (2009–12) of Operation IceBridge (OIB) surveys are examined. In our analysis, we found spurious spikes in the snow depth distributions of both the multi-year and seasonal ice covers. These spikes are artifacts that stem from the incorrect identification of side lobes and main lobes of the impulse response of the snow radar as returns from the air–snow interface. The current OIB snow depth retrieval algorithm does not explicitly account for the presence of these side lobes and main lobes. As a result, overall accuracy of snow depth returns and related statistics is negatively affected. Although the range locations of these side lobes are predictable for each radar installation, they vary with individual airborne campaigns. Comparisons with limited in situ snow surveys show significant differences of >20 cm between OIB and in situ snow surveys. These artifacts affect OIB ice thickness estimates because they rely on estimates of sea-ice freeboard, which are calculated as the differences between coincident snow freeboard from lidar elevations and the retrieved snow depth estimates discussed here. Since these products are widely distributed to the scientific community, our results suggest that earlier geophysical studies based on these products may need to be re-examined.
Analyses of the first aircraft multi-frequency, Polarimetric synthetic aperture radar (SAR) data acquired over the southwestern Greenland ice sheet are presented. Data were collected on 31 August 1989 by the Jet Propulsion Laboratory SAR using the NASA DC-8 aircraft. Along with curvilinear patterns associated with large-scale morphologic features such as crevasses, lakes and streams, frequency and polarization dependencies are observed in the P-, L-and C-band image products. Model calculations that include firn grain-size and volumetric water content suggest that tonal variations in and between the images are attributable to large-scale variations in the snow-and ice-surface characteristics, especially snow wetness. In particular, systematic trends in back-scatter strength observed at C-band across regions of changing snow wetness are suggestive of a capability to delineate boundaries between snow facies. Ice lenses and ice pipes are the speculated cause for similar trends in P-band back-scatter. Finally, comparison between SEASAT SAR data collected in 1978 and these airborne data collected in 1989 indicate a remarkable stability of surface patterns associated with the locations of supraglacial lake and stream systems.
The perennial ice concentration in the Beaufort Sea was examined using
active- and passive-microwave observations. We compared the ice type and
concentration estimates from SSM/I and ERS-1 SAR data over a seasonal cycle
from January 1992 to January 1993. It was found the multi-year (MY)
ice-concentration estimates from the SAR data were very stable and were
nearly equivalent to the ice concentration estimated at the end of the
previous summer. We contrast this with the variability of the MY
ice-concentration and ice-fraction estimates obtained using the NASA Team
algorithm. The passive- and active-microwave algorithms provide total ice
concentrations that are comparable during the winter, hut the passive
estimates are significantly lower during the summer. Passive-microwave
estimates of multi-year-ice concentrations are consistently lower (up to
30%) than those from the SAR data. We discuss reasons for these
discrepancies and the possible biases introduced by the active and passive
Introduction: Many emergency departments (EDs) have begun publishing wait times. This study seeks to develop an understanding of patients’ needs with respect to publishing ED wait times, which, to our knowledge, has not been described in the literature. Methods: We conducted a two-stage mixed methods study at a dual campus tertiary care academic center. First, we held focus group discussions comprising of 7 patient advocacy hospital committee members. Themes generated from focus group discussions were then utilized to create a patient survey. Focus groups were analyzed using content theme analysis. Hospital sites for survey administration were randomized and pre-assigned shifts were established to ensure a balance of weekdays, weekends, days, evenings, and overnights. All adult patients (age >18) in the waiting room were eligible, but excluded if they were directly referred to a specialty service or did not speak French or English. Survey data was analyzed using descriptive statistics. Results: We found 9 dominant focus group themes: definition of wait time, wait time posting, lack of communication, education in waiting room, patient expectations, utilization of the ED, patient behavior, physical comfort, and patient empowerment. Of the 240 patient questionnaires administered, 81.3% (195) wanted to know ED wait times before arrival to hospital and 90.8% (217) wanted ED wait times posted in the ED waiting room. The most popular choice for publishing wait times outside the ED was a website (46.7%) whereas, within the ED, patients were not particular about the specific display modality as long as times were displayed (39.6%). Overall, 76.7% (184) stated their satisfaction with the ED would be improved if wait times were posted. Conclusion: ED patients we surveyed strongly supported both the idea of having access to wait time information prior to arrival, as well as physical display of wait times in the waiting room.
The basic ideas in this paper are described in recently published papers by Ahern et al. (1977) and Kwok (1977). There are two main points to be made in addition, which remove the differences between these two papers.
A program to search for steady-state thermal emissions from stars has been in progress for several years in Canada (Purton 1976). In this program we have specifically excluded flaring objects (such as β Lyr or HR1099) where non-thermal emission is probably responsible. Out of the 30 or so detections, about 1/4 of them show a ~+1 spectral index, suggesting a 1/r2 density profile in the emitting region. This implies the existence of a non-static circumstellar envelope which is mostly likely the result of continuous mass outflow.
Studies for spin parameters and shapes of asteroids provide us with important information about the interior structure of asteroids and the physical processes they have undergone. A large sample of basic physical parameters can help us also understand the evolution of asteroids. There is scarce information for slowly-rotating larger asteroids because more effort is required for observing them. Because of this, we have established an international collaboration to study slowly-rotating asteroids. As the first step of this project, we have observed asteroids (168) Sibylla and (346) Hermentaria in 2014 and 2015 using several telescopes located in China, Chile, and U.S.A. Combining previous photometric data with our new data, we have performed preliminary analyses and obtained spin parameters and shapes with their uncertainties for these two slowly-rotating asteroids for the first time, using the convex inversion method and the virtual photometry Monte Carlo method. A pair of pole solutions for (168) Sibylla are found around (4.3°, 53.5°) and (183.5°, 52.6°) with a period of 47.0000 h. We have found that the shape of Sibylla resembles an oblate spheroid. For (346) Hermentaria, we have also found a pair of pole solutions around (134.5°, 16.7°) and (321.5°, 14.5°) with comparable rms-values with a spin period of about 17.79000 h, and a shape resembling a prolate spheroid.
We made dynamical black hole mass measurements from nineteen Seyfert 2 galaxies which host sub-parsec H2O maser disks using the H2O megamaser technique. The nearly perfect Keplerian rotation curves in many of these maser systems guarantee the high accuracy and precision of the black hole mass measurements. With the stellar velocity dispersion (σ∗) of the galaxy bulges measured with the Dupont 2.5 m telescope at Las Campanas Observatory in the South and the Apache Point Observatory (APO) 3.5m telescope in the North, we found that H2O maser galaxies, most of which host pseudo bulges rather than classical bulges, do not all follow the MBH–σ∗ relation shown in the literature. This result is well consistent with the latest findings by Kormendy & Ho (2013) that only early type galaxies and galaxies with classical bulges follow a tight MBH–σ∗ relation. Such a tight correlation may not exist in pseudo bulge galaxies.
Tricyclic antidepressants (TCAs) and serotonin norepinephrine reuptake inhibitors (SNRIs) (venlafaxine, duloxetine) are recommended as the first-line agents for peripheral neuropathic pain, especially for painful polyneuropathy, the other first-line options being gabapentinoids and topical lidocaine. Tricyclic antidepressants became a mainstay in the management of neuropathic pain before their mechanisms were elucidated and before the advent of systematic ways to evaluate their efficacy. Venlafaxine and duloxetine should be used with caution in patients with a history of mania, seizures, or bleeding tendency. Due to risk of excessive serotoninergic effect, they should be used with caution in patients receiving concomitant selective serotonin reuptake inhibitor (SSRI) or tramadol treatment. When selecting the treatment for an individual patient, comorbid conditions and their medications need to be taken into account. More detailed information of the effects of pharmacological agents on various symptoms of neuropathic pain and sensory profiles may guide drug selection in the future.
Ion beam synthesis of SiC/Si heterostructures was performed by MEVVA (metal vapor vacuum arc) implantation under various implantation and annealing conditions. The implanted SiC/Si heterostructures were characterized by various techniques. Carbon redistribution in overstoichiometrically implanted samples during annealing to form a stoichiometric SiC layer has been observed for the first time. The FTIR spectra were found to be composed of two components, one attributed to amorphous SiC and the other to β-SiC. It was also found that there are critical dose and critical energy at which the crystalline fraction increases abruptly. Other results on electrical and optical characterization are also presented and discussed