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Introduction: Many drugs, including cannabis and alcohol, cause impairment and contribute to motor vehicle collisions (MVCs). Policy makers require knowledge of the prevalence of drug use in crash-involved drivers, and types of drugs used in order to develop effective prevention programs. This issue is particularly relevant with the recent legalization of cannabis. We aim to study the prevalence of alcohol, cannabis, sedating medications, and other drugs in injured drivers from 4 Canadian Provinces. Methods: This prospective cohort study obtained excess clinical blood samples from consecutive injured drivers who attended a participating Canadian trauma centre following a MVC. Blood samples were analyzed using a broad spectrum toxicology screen capable of detecting cannabinoids, cocaine, amphetamines (including their major analogues), and opioids as well as psychotropic pharmaceuticals (including antihistamines, benzodiazepines, other hypnotics, and sedating antidepressants). Alcohol and cannabinoids were quantified. Health records were reviewed to extract demographic, medical, and MVC information using a standardized data collection tool. Results: This study has been collecting data in 4 trauma centres in British Columbia (BC) since 2011 and was launched in 2 trauma centres in Alberta (AB), 1 in Saskatchewan (SK), and 2 in Ontario (ON) in 2018. In preliminary results from BC (n = 2412), 8% of injured drivers tested positive for THC and 13% for alcohol. Preliminary results from other provinces (n = 301) suggest a regional variation in prevalence of drivers testing positive for THC (10% - 27%), alcohol (17% - 29%), and other drugs. By May 2018, an estimated 4500 cases from BC, 600 from AB, 150 from SK, and 650 from ON will have been analyzed. We will report the prevalence of positive tests for alcohol, THC, other recreational drugs, and sedating medications, pre and post cannabis legalization. The number of cases with alcohol and/or THC levels above Canadian per se limits will also be reported. Results will be reported according to province, driver sex, age, single vs. multi vehicle crashes, and requirement for hospital admission. Conclusion: This will be among the largest international datasets on drug use by injured drivers. Our findings will provide patterns of drug and alcohol impairment in 4 Canadian provinces pre and post cannabis legalization. The significance of these findings and implication for impaired driving policy and prevention programs in Canada will be discussed.
Background: Epileptic encephalopathy (EE) is a severe neurological disorder characterized by treatment-resistant seizures and poor neurodevelopmental outcomes. EE is associated with mutant genes, including those that encode for γ-aminobutyric acid type A (GABAA) receptor subunits. We identified a novel de novo GABRA1 mutation in a patient with EE, characterized its impact on GABAA receptor function, and sought potential therapeutic options. Methods: We described the clinical and electrophysiological features of a patient with a novel de novo GABRA1 (R214C) mutation; performed functional studies; and determined the effect of diazepam and insulin on wild type and mutant GABAA receptors. Results: The patient is a 10-year-old girl with EE, treatment-resistant seizures, intellectual disability and autism. Her GABRA1 (R214C) mutation dramatically decreased whole-cell GABA-evoked currents by reducing GABAA surface receptors, decreasing single channel open time, and altering channel kinetic properties. The combination of diazepam and insulin partially repaired these effects by enhancing channel activity and increasing the number of surface receptors, respectively. Conclusions: Diazepam and insulin partially mitigated a de novo GABRA1 (R214C) mutation’s effects on GABAA receptor number and function. Given the risks of insulin use, pharmacological agents with similar mechanisms of action but fewer side effects, such as IGF-1, should be studied and considered for clinical application.
Introduction: Online medical education resources are widely used in emergency medicine (EM), but strategies to assess quality remain elusive. We previously derived the Medical Education Translational Resources: Impact and Quality (METRIQ) 8 instrument to evaluate quality in medical education blog posts. Methods: As part of a subsequent validation study (The METRIQ Blog Study), a mixed-methods usability analysis was performed to obtain user feedback on the quality assessment instrument in order to improve its clarity and reliability. Participants in the METRIQ Study were first asked to rate five blog posts using the METRIQ-8 Score. They then evaluated the METRIQ-8 instruments ease of use and likelihood of being recommended to others using a 7-point Likert scale and free text comments. Participants were also asked to flag and comment on items within the score that they felt were unclear. Global usability ratings were summarized using median scores or percent rated unclear. We used ANOVA to test associations between ease of use and demographic factors. A thematic analysis was performed on the comments. Results: 309 EM medical students, residents, and attendings completed the survey. Global ratings were generally very favorable (median 2 [IQR 2-3], with 7 being the lowest score) for ease of use and likelihood of recommendation, and did not vary by participants country of origin, frequency of blog use, or learner level. Participants stated that the score was structured, systematic, and straightforward. They found it useful for junior learners and for guiding blog creation. Four questions in the score (questions 2, 4, 5, and 7) were identified by 10% of subjects to be unclear. Thematic analysis of comments identified suggested four main themes for improving the score: adding clearer definitions with marking rubrics; shortening the 7-point scale; adding items evaluating blog post presentation and utility; and, rephrasing the wording of certain questions for clarity. Conclusion: A mixed methods usability analysis of the METRIQ-8 instrument for assessing blog quality was globally well received by EM medical students, residents, and attendings. Qualitative analyses revealed multiple areas to improve the instruments clarity and usability. The METRIQ score is a promising instrument for evaluating the quality of blogs; further development and testing is needed to improve its utility.
The purpose of this study was to investigate whether significant difference exists on radiation dose delivered to organs at risks in megavoltage computed tomography (MVCT) verification using three predefined scanning modes, namely fine (2 mm), normal (4 mm) and coarse (6 mm). This will provide information for the imaging protocol of tomotherapy for the left breast.
Materials and methods
Organ doses were measured using thermoluminescent dosimeters (TLD-100) placed within a female Rando phantom for MVCT imaging. Kruskal–Wallis test was conducted with p<0·05 to evaluate the significant difference between the three MVCT scanning modes.
Statistically significant difference existed in organ absorbed dose between different scan mode selections (p<0·001). Relative to the normal scan selection (4 mm), the absorbed dose to the organs of interests can be scaled down by 0·7 and scaled up by 2·1 for coarse (6 mm) and fine scans (2 mm) respectively.
Optimisation of imaging protocols is of paramount importance to keep the radiation exposure ‘as low as reasonably achievable’. The recommendation of undergoing daily coarse mode for MVCT verification in breast tomotherapy not only mitigates the radiation exposure to normal tissues, but also trims the scan-acquisition time.
Schizotypal traits are considered a phenotypic-indicator of schizotypy, a latent personality organization reflecting a putative liability for psychosis. To date, no previous study has examined the comparability of factorial structures across samples originating from different countries and cultures. The main goal was to evaluate the factorial structure and reliability of the Schizotypal Personality Questionnaire (SPQ) scores by amalgamating data from studies conducted in 12 countries and across 21 sites.
The overall sample consisted of 27 001 participants (37.5% males, n = 4251 drawn from the general population). The mean age was 22.12 years (s.d. = 6.28, range 16–55 years). The SPQ was used. Confirmatory factor analysis (CFA) and Multilevel CFA (ML-CFA) were used to evaluate the factor structure underlying the SPQ scores.
At the SPQ item level, the nine factor and second-order factor models showed adequate goodness-of-fit. At the SPQ subscale level, three- and four-factor models displayed better goodness-of-fit indices than other CFA models. ML-CFA showed that the intraclass correlation coefficients values were lower than 0.106. The three-factor model showed adequate goodness of fit indices in multilevel analysis. The ordinal α coefficients were high, ranging from 0.73 to 0.94 across individual samples, and from 0.84 to 0.91 for the combined sample.
The results are consistent with the conceptual notion that schizotypal personality is a multifaceted construct and support the validity and utility of SPQ in cross-cultural research. We discuss theoretical and clinical implications of our results for diagnostic systems, psychosis models and cross-national mental health strategies.
Using the Mid-Infrared (MIRS) on board the Infrared Telescope in Space (IRTS) we obtained the 4.5 to 11.7 μm spectra of the stellar populations and diffuse interstellar medium in the Galactic bulge (l ≈ 8.7°, b ≈ 2.9, 4.0, 4.7, and 5.7°). Below galactic latitute of 4.0° the mid-infrared background spectra in the bulge are similar to the spectrum of M and K giants. The UIR bands (6.2, 7.7, 8.6, and 11.3 μm) are also detected in these regions and they are likely arising from the diffuse interstellar medium in the bulge. Above galactic latitude of 4.0°, the mid-infrared background spectra are similar to the spectrum of those evolved stars with high mass-loss rate detected by IRAS. One likely interpretation is that this background emission arises predominantly from these stars with very low luminosities that have not been detected by IRAS. The main-sequence life time for such low luminosity evolved stars is at least 10 Gyr, even in the metal poor cases. If these low luminosity evolved stars are metal-rich then the age would be much older. Thus, the existence of a large number (~ 75) of such low luminosity evolved stars in a small region (8′ × 8′) in the bulge would have significant impact on our understanding of the stellar content and the age of the Galactic bulge.
During 1990 we surveyed the southern sky using a multi-beam receiver at frequencies of 4850 and 843 MHz. The half-power beamwidths were 4 and 25 arcmin respectively. The finished surveys cover the declination range between +10 and −90 degrees declination, essentially complete in right ascension, an area of 7.30 steradians. Preliminary analysis of the 4850 MHz data indicates that we will achieve a five sigma flux density limit of about 30 mJy. We estimate that we will find between 80 000 and 90 000 new sources above this limit. This is a revised version of the paper presented at the Regional Meeting by the first four authors; the surveys now have been completed.
We present the KMOS (K-band Multi-Object Spectrograph) Cluster and VIRIAL (VLT IRIFU Absorption Line) Guaranteed Time Observation (GTO) programs. KMOS provides 24 arms each feeding an integral field unit (14×14 spaxels of 0.2″ pixels) for IZ, YJ, H and K band near infrared (NIR) medium resolution spectroscopy (R ∼ 3500). Targets are selected from a 7.2′ diameter patrol field. Ultra-deep spectroscopy of ∼ 80 early-type cluster galaxies (∼ 20hr on source) and ∼ 200 (∼ 10hr on source) early-type field galaxies at 1 < z < 2 will dramatically improve the situation at z > 1 for which measurements of stellar velocity dispersions and absorption indices are limited to a few, often relatively young passively evolving galaxies (e.g. Bezanson 2013). In ESO Periods P92 and P93, 15 nights worth of data has been collected for KMOS-Clusters and 6 nights for VIRIAL: this will be supplemented with more data in upcoming semesters. All galaxies have multiband HST imaging including existing or upcoming WFC3 IR imaging, providing stellar mass maps and sizes. Combined with our dispersion measurements, this will allow us to examine the fundamental plane and the dynamical mass of a large sample of z > 1 galaxies for the first time, for both cluster and field galaxies.
Electron backscatter diffraction (EBSD) has become a common technique for measuring crystallographic orientations at spatial resolutions on the order of tens of nanometers and at angular resolutions <0.1°. In a recent search of EBSD papers using Google Scholar™, 60% were found to address some aspect of deformation. Generally, deformation manifests itself in EBSD measurements by small local misorientations. An increase in the local misorientation is often observed near grain boundaries in deformed microstructures. This may be indicative of dislocation pile-up at the boundaries but could also be due to a loss of orientation precision in the EBSD measurements. When the electron beam is positioned at or near a grain boundary, the diffraction volume contains the crystal lattices from the two grains separated by the boundary. Thus, the resulting pattern will contain contributions from both lattices. Such mixed patterns can pose some challenge to the EBSD pattern band detection and indexing algorithms. Through analysis of experimental local misorientation data and simulated pattern mixing, this work shows that some of the rise in local misorientation is an artifact due to the mixed patterns at the boundary but that the rise due to physical phenomena is also observed.
Quantum dot gate (QDG) field-effect transistors (FET) have shown three-state transfer characteristics. Quantum dot channel (QDC) field-effect transistors (FET) have exhibited fourstate ID-VG characteristics. This project aims at studying the effect of incorporating cladded quantum dot layers in the gate region of QDC-FET. Four-state characteristics are explained by carrier transport in narrow energy mini-bands which are manifested in a quantum dot superlattice (QDSL) channel. QDSL is formed by an array of cladded quantum dots (such as SiOx-Si and GeOx-Ge). Multi-state FETs are needed in multi-valued logic (MVL) that can reduce the number of gates and transistors in digital circuits. The fabricated device showed the four-state characteristic (OFF, ‘I1’, ‘I2’, ON).
The use of plasma immersion ion implantation (PIII) as a novel method for the treatment of polymer surfaces is investigated. The effect of PIII treatment on the coefficient of friction, contact angle modification, and surface energy of silicone and EPDM (ethylene-propylene-diene monomer) rubber are investigated as a function of pulse voltage, treatment time, and gas species. Low energy (0 - 8 keV) and high dose (∼1017 - 1018 ions/cm2) implantation of N2, Ar, and CF4 is performed using an inductively coupled plasma source (ICP) at low pressure (0.2 mTorr). PIII treatment reduces the coefficient of friction (μ) of silicone rubber from μ = 0.464 to the range μ = 0.176 – 0.274, and μ of EPDM rubber decreases from 0.9 to the range μ = 0.27 – 0.416 depending on processing conditions. The contact angle of water and diiodomethylene decreases after implantation and increases at higher doses for both silicone and EPDM rubber.
In this paper we present a set of wave flume experiments for a solitary wave reflecting off a vertical wall. A particle tracking velocimetry (PTV) technique is used to measure free-surface velocity and the velocity field in the vicinity of the moving contact line. We observe that the free surface undergoes the so-called rolling motion as the contact line moves up and down the vertical wall, and fluid particles on the free surface almost always flow toward the wall except at the end of the reflection process. As the contact line descends along the wall, wall boundary layer flows move in a downward direction and therefore the boundary layer acts like a conduit through which the surface-rolling-induced flow escapes from the meniscus. However, during the last phase of the reflection process flow reversal occurs inside the wall boundary layer. An approximate analytical solution is developed to explain the flow reversal feature. Very good agreement between the approximate theory and measured data is obtained. Because of the flow reversal, boundary layer flows collide with the surface-rolling-induced flows. The collision gives rise to a jet ejecting from the meniscus into the water body, which later evolves into a small eddy. It is noticed that the fluid particles in different regions such as the free stream, the free-surface boundary layer and the wall boundary layer, can be transported to other regions by passing through the meniscus.
This article simulates highly overlapped projections of spherical particles that are distributed randomly in space. The size and number of the features in the projections are examined as well as how these features change with particle size and concentration. First, there are discernable features in projection even when particles overlap extensively, and the size of these discernable features is the expected size of an individual particle. Second, the number of features increases with specimen thickness at a rate of t0.543 when the specimen thickness is below a critical value and becomes independent of specimen thickness at higher thicknesses. A criterion is established for the critical thickness based on particle size and particle volume fraction. When the specimen thickness is known and smaller than the critical thickness, a single representative transmission electron microscopy (TEM) (or scanning TEM) image exhibiting extensive particle overlap can be used to determine the size and number density of the spherical particles.
We study the effects of emergent coastal forests on the propagation of long surface waves of small amplitude. The forest is idealized by an array of vertical cylinders. Simple models are employed to represent bed friction and to simulate turbulence generated by flow through the tree trunks. A multi-scale (homogenization) analysis similar to that for seepage flows is carried out to deduce the effective equations on the macro-scale. The effective coefficients are calculated by numerically solving the micro-scale problem in a unit cell surrounding one or several cylinders. Analytical and numerical solutions for wave attenuation on the macro-scale for different bathymetries and coastal forest configurations are presented. For a transient incident wave, analytical results are discussed for the damping of a leading tsunami. For comparison series of laboratory data for periodic and transient incident waves are also presented. Good agreement is found even though some of the measured waves are short or nonlinear.
Limited information is available on the health outcomes of the rural older population in developing countries is affected by disasters. In October 2010, Hainan Province experienced severe flooding following heavy rains. Nearly four million people were affected and many had undergone resettlement. This study investigated the impacts of the flooding on people living in the disaster-affected rural communities. The findings were compared with baseline information collected in 2010 about health issues in rural villages in Hainan. Health outcome comparisons also were made between ethnic groups (Han versus Li).
A two-stage cluster-sampling, cross-sectional post-disaster study was conducted. The entire Hainan Island was categorized into ranks of different severity in rainfall amount and associated damage in October (most severe, intermediate, least severe). The county with the most rainfall and the most severe ranking and the one with least rainfall and the least severe ranking were identified. In each county, one Han and one Li village were chosen by using a computer-generated random number, so four villages were sampled in total. More than 100 individuals ≥ 50 years of age were interviewed by face-to-face survey. Data on disaster-related injuries, socio-demographic information, non-communicable disease, lifestyle, and mental health were collected.
Findings indicated the severity of impact was associated with self-reported health outcomes of older population. Gender and ethnic differences were found in reported health outcomes. Predictors of adverse post-disaster health outcomes in older populations in rural communities were identified.
The results demonstrated significant differences in the impacts of flooding in rural populations. Targeted services and interventions should be planned to address the disparity and meet the physical and mental health needs post-disaster.
Homoepitaxial Si layers were grown on Si(100) at temperatures of 325 - 500 °C by Electron-Cyclotron Resonance Plasma-Enhanced Chemical Vapor Deposition (ECR PECVD) from a gas mixture of SiH4,H2 and Ar. Ar was added in order to realize high growth rates where the breakdown of epitaxy was well observed. Si disorder depth profiles derived from RBS channeling spectra were compared with hydrogen depth distributions measured by Heavy-Ion Elastic Recoil Detection Analysis (HI-ERDA) and Secondary Ion Mass Spectroscopy (SIMS). The results suggest that the transition from epitaxial to amorphous growth proceeds through two stages: (1) a highly defective but still ordered growth with the defect density increasing as the growth proceeds and (2) the formation of conically shaped precipitates of amorphous Si. Both regions act as an increasingly effective sink for excessive hydrogen which diffuses from the growth surface into the bulk of the sample. In perfectly grown epitaxial films, where the overall concentration of excessive hydrogen was low, the hydrogen diffusion tail was found to extend far beyond the interface into the Si substrate.
We present herein recent findings of an investigation of catalyst assembly and activation using metallic nanoparticles encapsulated with organic monolayers. Gold nanocrystals (2∼5 nm) encapsulated with thiolate monolayers assembled on electrode surfaces, were found to be catalytically active towards electrooxidation of CO and MeOH upon activation. The activation involved partial removal of the encapsulating thiolates and the formation of surface oxygenated species. A polymeric film was also used as a substrate for the assembly of the nanoparticle catalysts. When the polymer matrix was doped with small amounts of Pt, a remarkable catalytic activity was observed. These catalysts were characterized utilizing cyclic voltammetry and atomic force microscopy.