To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Apolipoprotein E (APOE) E4 is the main genetic risk factor for Alzheimer’s disease (AD). Due to the consistent association, there is interest as to whether E4 influences the risk of other neurodegenerative diseases. Further, there is a constant search for other genetic biomarkers contributing to these phenotypes, such as microtubule-associated protein tau (MAPT) haplotypes. Here, participants from the Ontario Neurodegenerative Disease Research Initiative were genotyped to investigate whether the APOE E4 allele or MAPT H1 haplotype are associated with five neurodegenerative diseases: (1) AD and mild cognitive impairment (MCI), (2) amyotrophic lateral sclerosis, (3) frontotemporal dementia (FTD), (4) Parkinson’s disease, and (5) vascular cognitive impairment.
Genotypes were defined for their respective APOE allele and MAPT haplotype calls for each participant, and logistic regression analyses were performed to identify the associations with the presentations of neurodegenerative diseases.
Our work confirmed the association of the E4 allele with a dose-dependent increased presentation of AD, and an association between the E4 allele alone and MCI; however, the other four diseases were not associated with E4. Further, the APOE E2 allele was associated with decreased presentation of both AD and MCI. No associations were identified between MAPT haplotype and the neurodegenerative disease cohorts; but following subtyping of the FTD cohort, the H1 haplotype was significantly associated with progressive supranuclear palsy.
This is the first study to concurrently analyze the association of APOE isoforms and MAPT haplotypes with five neurodegenerative diseases using consistent enrollment criteria and broad phenotypic analysis.
Angiostrongylus cantonensis is a pathogenic nematode and the cause of neuroangiostrongyliasis, an eosinophilic meningitis more commonly known as rat lungworm disease. Transmission is thought to be primarily due to ingestion of infective third stage larvae (L3) in gastropods, on produce, or in contaminated water. The gold standard to determine the effects of physical and chemical treatments on the infectivity of A. cantonensis L3 larvae is to infect rodents with treated L3 larvae and monitor for infection, but animal studies are laborious and expensive and also raise ethical concerns. This study demonstrates propidium iodide (PI) to be a reliable marker of parasite death and loss of infective potential without adversely affecting the development and future reproduction of live A. cantonensis larvae. PI staining allows evaluation of the efficacy of test substances in vitro, an improvement upon the use of lack of motility as an indicator of death. Some potential applications of this assay include determining the effectiveness of various anthelmintics, vegetable washes, electromagnetic radiation and other treatments intended to kill larvae in the prevention and treatment of neuroangiostrongyliasis.
Oral anticoagulation (OAC) reduces stroke risk in patients with atrial fibrillation (AF) or atrial flutter (AFL). However, OAC initiation rates in patients discharged directly from the emergency department (ED) are low. We aimed to address this care gap by implementing a quality improvement intervention.
The study was performed in four Canadian urban EDs between 2015 and 2016. Patients were included if they had an electrocardiogram (ECG) documenting AF/AFL in the ED, were directly discharged from the ED, and were alive after 90 days. Baseline rates of OAC initiation were determined prior to the intervention. Between June and December 2016, we implemented our intervention in two EDs (ED-intervention), with the remaining sites acting as controls (ED-control). The intervention included a reminder statement prompting OAC initiation according to guideline recommendations, manually added to ECGs with a preliminary interpretation of AF/AFL, along with a decision-support algorithm that included a referral sheet. The primary outcome was the rate of OAC initiation within 90 days of the ED visit.
Prior to the intervention, 37.2% OAC-naïve patients with ECG-documented AF/AFL were initiated on OAC. Following implementation of the intervention, the rate of OAC initiation increased from 38.6% to 47.5% (absolute increase of 8.5%; 95% CI, 0.3% to 16.7%, p=0.04) among the ED-intervention sites, whereas the rate remained unchanged in ED-control sites (35.3% to 35.9%, p=0.9).
Implementation of a quality improvement intervention consisting of a reminder and decision-support tool increased initiation of OAC in high-risk patients. This support package can be readily implemented in other jurisdictions to improve OAC rates for AF/AFL.
Two radiocarbon (14C) excursions are caused by an increase of incoming cosmic rays on a short time scale found in the Late Holocene (AD 774–775 and AD 993–994), which are widely explained as due to extreme solar proton events (SPE). In addition, a larger event has also been reported at 5480 BC (Miyake et al. 2017a), which is attributed to a special mode of a grand solar minimum, as well as another at 660 BC (Park et al. 2017). Clearly, other events must exist, but could have different causes. In order to detect more such possible events, we have identified periods when the 14C increase rate is rapid and large in the international radiocarbon calibration (IntCal) data (Reimer et al. 2013). In this paper, we follow on from previous studies and identify a possible excursion starting at 814–813 BC, which may be connected to the beginning of a grand solar minimum associated with the beginning of the Hallstatt period, which is characterized by relatively constant 14C ages in the period from 800–400 BC. We compare results of annual 14C measurements from tree rings of sequoia (California) and cedar (Japan), and compare these results to other identified excursions, as well as geomagnetic data. We note that the structure of the increase from 813 BC is similar to the increase at 5480 BC, suggesting a related origin. We also assess whether there are different kinds of events that may be observed and may be consistent with different types of solar phenomena, or other explanations.
We present a phylogenetic revision of the Sticta filix morphodeme in New Zealand. This non-monophyletic group of early diverging clades in the genus Sticta is characterized by a stalked thallus with a green primary photobiont and the frequent formation of a dendriscocauloid cyanomorph. Traditionally, three species have been distinguished in New Zealand: S. filix (Sw.) Nyl., S. lacera (Hook. f. & Taylor) Müll. Arg. and S. latifrons A. Rich., with two cyanomorphs separated under the names Dendriscocaulon dendriothamnodes Dughi ex D. J. Galloway (traditionally associated with S. latifrons) and D. dendroides (Nyl.) R. Sant. ex H. Magn. (traditionally associated with S. filix). Sticta lacera was not included in the present study due to the lack of authentic material (all specimens originally identified under that name and sequenced clustered with S. filix); S. filix was confirmed as a distinct species whereas S. latifrons s. lat. was shown to represent two unrelated species, S. latifrons s. str. and the reinstated S. menziesii Hook. f. & Taylor. The cyanomorphs of S. filix and S. latifrons are not conspecific with the types of the names D. dendriothamnodes and D. dendroides, respectively; the D. dendriothamnodes cyanomorph belongs to the Australian taxon Sticta stipitata C. Knight ex F. Wilson, which is not present in New Zealand, whereas the D. dendroides cyanomorph corresponds to a previously unrecognized species with unknown chloromorph, recombined here as Sticta dendroides (Nyl.) Moncada, Lücking & de Lange. Thus, instead of three species (S. filix, S. lacera, S. latifrons) with their corresponding cyanomorphs, five species are now distinguished in this guild in New Zealand: S. dendroides (cyanomorph only), S. filix (chloro- and cyanomorph), S. lacera (chloromorph only), S. latifrons (chloro- and cyanomorph) and S. menziesii (chloro- and cyanomorph). A key is presented for identification of the chloromorphs and the dendriscocauloid cyanomorphs of all species. Semi-quantitative analysis suggests that species in this guild are good indicators of intact forest ecosystems in New Zealand and that the two newly recognized species, S. dendroides and S. menziesii, appear to perform particularly well in this respect. The use of lichens as bioindicators of environmental health is not yet established in New Zealand and so, based on our results, we make the case to develop this approach more thoroughly.
In recent years there has been an increasing interest in the issue of farm animal welfare. This interest stems from a belief that many modern livestock production systems do not allow animals to perform a natural range of behaviour, leading to a possible decline in welfare. One method of determining the value of natural behaviours is to perform preference tests. In dairy cows, choices relating to various treatments, including feeding, shouting, electric shock, hitting (Pajor et al., 2003) and being milked (Prescott et al., 1998) have been assessed using Y-maze methodology. This is a process that involves training animals to anticipate receiving a treatment if they enter one arm of the Y and an alternative treatment if they enter the other. We used preference tests as a tool to determine how dairy cows perceive aspects of their feeding environment, with specific emphasis on understanding what difficulties low ranking animals face at the feed-face. We hypothesised that subordinate cows would trade-off proximity to a dominant individual at the feed-face with access to food of a high quality.
Although procedural sedation for cardioversion is a common event in emergency departments (EDs), there is limited evidence surrounding medication choices. We sought to evaluate geographic and temporal variation in sedative choice at multiple Canadian sites, and to estimate the risk of adverse events due to sedative choice.
This is a secondary analysis of one health records review, the Recent Onset Atrial Fibrillation or Flutter-0 (RAFF-0 [n=420, 2008]) and one prospective cohort study, the Recent Onset Atrial Fibrillation or Flutter-1 (RAFF-1 [n=565, 2010 – 2012]) at eight and six Canadian EDs, respectively. Sedative choices within and among EDs were quantified, and the risk of adverse events was examined with adjusted and unadjusted comparisons of sedative regimes.
In RAFF-0 and RAFF-1, the combination of propofol and fentanyl was most popular (63.8% and 52.7%) followed by propofol alone (27.9% and 37.3%). There were substantially more adverse events in the RAFF-0 data set (13.5%) versus RAFF-1 (3.3%). In both data sets, the combination of propofol/fentanyl was not associated with increased adverse event risk compared to propofol alone.
There is marked variability in procedural sedation medication choice for a direct current cardioversion in Canadian EDs, with increased use of propofol alone as a sedation agent over time. The risk of adverse events from procedural sedation during cardioversion is low but not insignificant. We did not identify an increased risk of adverse events with the addition of fentanyl as an adjunctive analgesic to propofol.
Two–dimensional hydrodynamic equations for laminar, viscous flow, and admitting a frictional slip-plane lower boundary are applied to the modeling of snow-avalanche impact on rigid wall structures. Predicted maximum pressures and pressures versus time are compared with published experimental results, and general correspondence is established. Impact pressure versus time is found to depend upon the shape of the avalanche leading edge, for which general information is lacking. Computer modeling of more complex structural configurations is feasible using the methodology reported.
Because individuals develop dementia as a manifestation of neurodegenerative or neurovascular disorder, there is a need to develop reliable approaches to their identification. We are undertaking an observational study (Ontario Neurodegenerative Disease Research Initiative [ONDRI]) that includes genomics, neuroimaging, and assessments of cognition as well as language, speech, gait, retinal imaging, and eye tracking. Disorders studied include Alzheimer’s disease, amyotrophic lateral sclerosis, frontotemporal dementia, Parkinson’s disease, and vascular cognitive impairment. Data from ONDRI will be collected into the Brain-CODE database to facilitate correlative analysis. ONDRI will provide a repertoire of endophenotyped individuals that will be a unique, publicly available resource.
We sought to conduct a major objective of the CAEP Academic Section, an environmental scan of the academic emergency medicine programs across the 17 Canadian medical schools.
We developed an 84-question questionnaire, which was distributed to academic heads. The responses were validated by phone by the lead author to ensure that the questions were answered completely and consistently. Details of pediatric emergency medicine units were excluded from the scan.
At eight of 17 universities, emergency medicine has full departmental status and at two it has no official academic status. Canadian academic emergency medicine is practiced at 46 major teaching hospitals and 13 specialized pediatric hospitals. Another 69 Canadian hospital EDs regularly take clinical clerks and emergency medicine residents. There are 31 full professors of emergency medicine in Canada. Teaching programs are strong with clerkships offered at 16/17 universities, CCFP(EM) programs at 17/17, and RCPSC residency programs at 14/17. Fourteen sites have at least one physician with a Master’s degree in education. There are 55 clinical researchers with salary support at 13 universities. Sixteen sites have published peer-reviewed papers in the past five years, ranging from four to 235 per site. Annual budgets range from $200,000 to $5,900,000.
This comprehensive review of academic activities in emergency medicine across Canada identifies areas of strengths as well as opportunities for improvement. CAEP and the Academic Section hope we can ultimately improve ED patient care by sharing best academic practices and becoming better teachers, educators, and researchers.
Very Large Array (VLA) synthesis maps of the total intensity and the circular polarization of three active regions at 6 cm wavelength are presented. The radiation from each active region is dominated by a few intense cores with angular sizes of ~ 0.5′, brightness temperatures of ~ 106 K, and degrees of circular polarization of 30 to 90%. Some of the core sources within a given active region exhibit opposite senses of circular polarization, suggesting the feet of magnetic dipoles, and the high brightness temperatures suggest that these magnetic structures belong to the low solar corona. We also present comparisons between our VLA maps of circular polarization and Zeeman effect magnetograms of the lower lying photosphere. There is an excellent correlation between the magnetic structures inferred by the two methods, indicating that synthesis maps of circular polarization at 6 cm can be used to delineate magnetic structures in the low solar corona.
Teacher-pupil relationships have been found to mediate behavioural,
social and psychological outcomes for children at different ages
according to teacher and child report but most studies have been
To explore later psychiatric disorder among children with problematic
Secondary analysis of a population-based cross-sectional survey of
children aged 5-16 with a 3-year follow-up.
Of the 3799 primary-school pupils assessed, 2.5% of parents reported
problematic teacher-pupil relationships; for secondary-school pupils
(n=3817) this rose to 6.6%. Among secondary-school
pupils, even when children with psychiatric disorder at baseline were
excluded and we adjusted for baseline psychopathology score, problematic
teacher-pupil relationships were statistically significantly related to
higher levels of psychiatric disorder at 3-year follow-up (odds ratio
(OR) = 1.93, 95% CI 1.07-3.51 for any psychiatric disorder, OR=3.00, 95%
CI 1.37-6.58 for conduct disorder). Results for primary-school pupils
were similar but non-significant at this level of adjustment.
This study underlines the need to support teachers and schools to develop
positive relationships with their pupils.
It is believed that when patients present to the emergency department (ED) with recent-onset atrial fibrillation or flutter (RAFF), controlling the ventricular rate before cardioversion improves the success rate. We evaluated the influence of rate control medication and other variables on the success of cardioversion.
This secondary analysis of a medical records review comprised 1,068 patients with RAFF who presented to eight Canadian EDs over 12 months. Univariate analysis was performed to find associations between predictors of conversion to sinus rhythm including use of rate control, rhythm control, and other variables. Predictive variables were incorporated into the multivariate model to calculate adjusted odds ratios (ORs) associated with successful cardioversion.
A total of 634 patients underwent attempted cardioversion: 428 electrical, 354 chemical, and 148 both. Adjusted ORs for factors associated with successful electrical cardioversion were use of rate control medication, 0.39 (95% confidence interval [CI] 0.21-0.74); rhythm control medication, 0.28 (95% CI 0.15-0.53); and CHADS2 score > 0, 0.43 (95% CI 0.15-0.83). ORs for factors associated with successful chemical cardioversion were use of rate control medication, 1.29 (95% CI 0.82-2.03); female sex, 2.37 (95% CI 1.50-3.72); and use of procainamide, 2.32 (95% CI 1.43-3.74).
We demonstrated reduced successful electrical cardioversion of RAFF when patients were pretreated with either rate or rhythm control medication. Although rate control medication was not associated with increased success of chemical cardioversion, use of procainamide was. Slowing the ventricular rate prior to cardioversion should be avoided.
We studied the effect of carbon incorporation on the material and electrical properties of Ta2O5 thin film. We doped the Ta2O5 films with carbon using pulsed-dc reactive and rfmagnetron sputtering of Ta2O5 performed in an Ar/O2/CO2 plasma. In thick (70 nm) films, an optimal amount (0.8 - 1.4 at.%) of carbon doping reduced the leakage current to 10−8 A/cm2 at +3 MV/cm, a four orders of magnitude reduction compared to that in a pure Ta2O5 film grown in similar conditions without CO2 in the plasma. This finding suggests that carbon doping can significantly improve the dielectric leakage property at an optimal concentration. X-ray Photoemission Spectroscopy (XPS) analysis showed the presence of carbonate in these electrically improved carbon-doped films. Analysis by high-resolution transmission electron microscopy (HRTEM) exhibited no morphological or structural changes in these carbon doped films. Carbon doping showed no improvement in the leakage current in thin (10 nm) Ta2O5 films. This phenomenon is explained by a defect compensation mechanism, in which the carbon-related defects remove carriers at low concentrations but form a hopping conduction path at high concentrations.