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We have updated the migraine prevention guideline of the Canadian Headache Society from 2012, as there are new therapies available, and additionally, we have provided guidelines for the prevention of chronic migraine, which was not addressed in the previous iteration.
Methods:
We undertook a systematic review to identify new studies since the last guideline. For studies identified, we performed data extraction and subsequent meta-analyses where possible. We composed a summary of the evidence found and undertook a modified Delphi recommendation process. We provide recommendations for treatments identified and additionally expert guidance on the use of the treatments available in important clinical situations.
Results:
We identified 61 studies that were included in this evidence update and identified 16 therapies we focused on. The anti-calcitonin gene-related peptide (CGRP) agents were approved by Health Canada between 2018 and 2024 and provide additional options for episodic and chronic migraine prevention. We also summarize evidence for the use of propranolol, topiramate and onabotulinumtoxinA in addition to anti-CGRP agents as treatments for chronic migraine. We have downgraded topiramate to a weak recommendation for use and gabapentin to a weak recommendation against its use in episodic migraine. We have weakly recommended the use of memantine, levetiracetam, enalapril and melatonin in episodic migraine.
Conclusion:
Based on the evidence synthesis, we provide updated recommendations for the prevention of episodic and chronic migraine utilizing treatments available in Canada. We additionally provided expert guidance on their use in clinical situations.
Starting in the 1960s, the flea beetle Longitarsus jacobaeae (Waterhouse) (Coleoptera: Chrysomelidae) has been imported and relocated to North America for the control of the weed tansy ragwort, Jacobaea vulgaris (Asteraceae). Some Longitarsus species are morphologically almost indistinguishable, leading to questions regarding the taxonomic identity of the beetles released. Here, we present the results of a molecular study that addresses these questions and updates a list of the releases of Longitarsus within Canada. Our findings confirm the suspected release of the cryptic species L. flavicornis concurrent with releases of L. jacobaeae at sites in British Columbia, Canada, in the 1970s. However, we find no evidence for the continued presence of L. flavicornis at historical release sites in British Columbia nor in Nova Scotia, Canada, where it might potentially have been redistributed. We confirm the presence of L. gracilis Kutschera in Nova Scotia and British Columbia, the latter population likely established from a 2005 release of Longitarsus from Nova Scotia. To our knowledge, this study provides the first published confirmation of L. gracilis in Canada. Finally, we provide evidence that what were recognised in earlier work as three separate taxa (L. succineus (Foudras), L. near noricus, and Longitarsus sp.) are likely all L. succineus.
We give a generators-and-relations description of the reduced versions of quiver quantum toroidal algebras, which act on the spaces of BPS states associated to (noncompact) toric Calabi–Yau threefolds X. As an application, we obtain a description of the K-theoretic Hall algebra of (the quiver with potential associated to) X, modulo torsion.
Late-onset sepsis (LOS) in the neonatal intensive care unit (NICU) causes significant morbidity and mortality, yet guidance on empiric management is limited. We surveyed NICUs across Canada and the United States regarding their empiric antimicrobial regimens for LOS, thereby identifying large practice variations and high rates of empiric vancomycin use.
This paper presents the design and analysis of a compact eight-port multiband multiple-input–multiple-output (MIMO) antenna for 5G smartphones. The proposed antenna structure is designed using meandering elements, as radiator, on the FR4 substrate of 150 × 80 × 0.8 mm with loss tangent (tan δ) of 0.02 and relative permittivity (εr) of 4.4. The proposed antenna resonates at 2.4, 3.5, and 5.5 GHz, and it covers the bandwidth of 2%, 6.28%, and 2.53%, respectively. The measured results provide an omnidirectional radiation pattern with 58%–78% of efficiency in all operating bands. The eight-port multiband MIMO design provides a high isolation of 17.5 dB, envelope correlation coefficient < 0.04, diversity gain of 9.98 dB, total active reflection coefficient < −10 dB, and channel capacity loss of <0.25 bits/s/Hz. Also, the hand phantom is designed to analyze the reflection coefficients and efficiency of the proposed antenna.
A growing number of institutions that hold cultural heritage artifacts are now considering voluntary repatriations in which they choose to return an artifact despite unfilled gaps in their knowledge of its ownership history. But how are institutions to judge whether it is more probable that such gaps conceal theft and illicit export or are innocuous? Attempting to answer this question for Nepal, we examine published and archival records to trace the history of the growth in collecting of Nepali cultural heritage in the United States, with special attention to a 1964 exhibition at New York’s Asia Society Gallery, “The Art of Nepal,” and the activity of the New York dealers Nasli and Alice Heeramaneck. We conclude that the majority of Nepali heritage items in America entered after Nepal prohibited their export.
The increasing demand for food and especially proteins leads to the search for alternative protein sources. Meat co-products, which are available but little used in human food, provide a potential solution to this challenge. The present study aimed to evaluate the nutritional quality of two beef protein ingredients (greasy greaves recovered proteins (GGRP) and water recovered proteins (WRP)), both co-products of the fat rendering process. Their true ileal digestibility (TID), digestible indispensable amino acid score (DIAAS) and kinetics of plasma amino acids (AA) were measured in ten growing pigs, each fed the two co-products and a protein-free diet. Titanium dioxide was used as an indigestible marker. Digesta samples were collected for 9 h after meal ingestion, and blood samples were collected at ten time points during the same period. Total nitrogen (N) and AA contents were determined. Data were statistically analysed using linear mixed models. The TID of total N was not different between WRP and GGRP (81–84 %, P > 0·05). The first-limiting AA was Trp for both ingredients, with a DIAAS much higher for GGRP than for WRP (74 and 10 % for adults, respectively; P < 0·001). Postprandial plasma AA concentration peaked earlier for WRP (3 h) than for GGRP (5 h). Plasma concentrations of total and essential AA were higher (P < 0·001) with GGRP diet than WRP diet. Overall, GGRP has a nutritional quality suitable to meet the needs of adults for AA, while WRP needs to be supplemented with other protein sources to fulfil the dietary requirements.
This article addresses whether responses to COVID-19 created opportunities for future policy change. We explore this matter by presenting a framework rooted in political economy and the literature on pandemics. We argue that the opportunities created by emergency responses are context-specific and that narratives, policy tools, and pro-equity state actors are variables that mediate emergency responses and future opportunities. We ground our analytical contribution on the emergency cash transfers deployed during 2020 following the COVID-19 outbreak in two contrasting Central American countries, Costa Rica and Guatemala. The paper promotes further policy discussion on the opportunities for progressive change in unequal contexts.
Medical ethics education is crucial for medical students and trainees, helping to shape attitudes, beliefs, values, and professional identities. Exploration of ethical dilemmas and approaches to resolving them provides a broader understanding of the social and cultural contexts in which medicine is practiced, as well as the ethical implications of medical decisions, fostering critical thinking and self-reflection skills imperative to providing patient-centered care. However, exposure to medical ethics topics and their clinical applications can be limited by curricular constraints and the availability of institutional resources and expertise. Podcasts, among other Free Open Access Medical Education (FOAMed) resources, are a novel educational tool that offers particular advantages for self-directed learning, a process by which learners engage in asynchronous educational opportunities outside of traditional academic or clinical settings. Podcasts can be readily distributed to wide audiences and played at any time, reducing barriers to access and offering a level of flexibility that is not possible with traditional forms of education and is well-suited to busy schedules. Podcasts can also use real voices and storytelling to make the content memorable and eminently human. This paper describes the development, production process, and impact of Core IM’s “At the Bedside,” a podcast focusing on issues in medical ethics and the medical humanities, intending to supplement standard bioethics curricula in an accessible, relevant, and engaging way. The authors advocate for broad incorporation of podcasts into medical ethics education.
Many bioethicists have recently shifted from using “physician-assisted suicide” (PAS) to “medical aid-in-dying” (MAID) to refer to the act of voluntarily hastening one’s death with the assistance of a medical provider. This shift was made to obscure the practice’s connection to “suicide.” However, as the charge of “suicide” is fundamental to arguments against the practice, “MAID” can only be used by its proponents. The result has been the fragmentation of the bioethical debate. By highlighting the role of human agency—as opposed to natural processes—in causing death, the term “PAS” makes it easier both to perceive potential risks to vulnerable populations and to affirm suicide as a potentially autonomous choice. As such, “PAS” thus more transparently expresses the arguments of both supporters and opponents of the “right to die,” while avoiding the unnecessary stigmatization of suicide and suicidal people which is a result of the usage of “MAID.”
In transonic flow conditions, buffeting associated with finite-amplitude lift fluctuations can limit the operational envelope of an aircraft. For both airfoils and wings, these oscillations have been linked to global flow instabilities that arise from a Hopf bifurcation. We employ a combination of numerical simulations and global stability analysis to investigate the near-critical behaviour of the oscillatory buffet-onset instability on airfoils. The flow is governed by the unsteady Reynolds-averaged Navier–Stokes equations, with a basic state provided by a steady-state solution. In the weakly nonlinear formulation, the disturbance amplitude is described by the Landau equation. The linear growth rate can be determined from either the simulations or the stability analysis, and the Landau constant is derived from simulations resulting in finite-amplitude equilibrium states. The results show that the Landau constant is nearly independent of Mach number and angle of attack for a given airfoil. Using the Landau constant derived from a small number of simulations, the stability analysis can be employed to efficiently capture the essential finite-amplitude behaviour needed to estimate the buffet-onset boundary. The stability analysis is shown to capture the envelope of lift oscillations during a continuous pitch of an airfoil, from pre-buffet through post-buffet lift levels.
Do inputs need to be restricted on a language-specific basis? Classic Optimality Theory claims that they do not: the rich base is filtered by constraints that yield full contrast, complementary distributions or positional neutralisation depending on the ranking. The problem arises when positional neutralisation affects a gappy contrast. In Russian, voicing neutralisation works on all obstruents alike, including non-contrastively voiceless ones – but it creates voiced allophones that are otherwise disallowed. In the popular OT account of positional neutralisation, analysing these cases requires handling voicing twice: once for all segments, then again for gaps. I argue that the solution is to relax the rich base assumption by ruling gaps out at the UR level through morpheme structure constraints (Halle 1959 et seq.).