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The LEME Corpus Manual has an editorial introduction, indexes of subjects, proper names, and chronology, a primary bibliography of LEME corpus texts, as well as English language texts not included in the Corpus, a description of the XML encoding and of lemmatization and source analysis tools. The appendix includes lists of language abbreviations and of abbreviations for parts of speech.Social Sciences and Humanities Research Council of CanadaCanada Foundation for InnovationUniversity of Toronto LibrariesUniversity of Toronto PressInformation & Instructional Technology, Faculty of Arts and Science, University of Toront
Effect of varying frequency of a synthetic jet on flow separation over an airfoil
An experimental investigation on the effects of the synthetic jet actuator (SJA) was conducted on a NACA (National Advisory Committee for Aeronautics) 0025 airfoil in a low-speed recirculating wind tunnel at a chord Reynolds number of 100,000 and at an angle of attack 12°. Particle image velocimetry was used to visualize the flow separation for the uncontrolled baseline flow, and the flow attachment for the SJA controlled flows. The location of the SJA was at -1.3% from the separation point, and a blowing ratio of 0.8 was chosen for this study. The blowing ratio proved to be effective in suppressing the separation of the flow. The reduced frequency () was varied between 1, 2, 14, and 58. The momentum bursts from the SJA based on the reduced frequency determined the effectiveness of the control method. The Reynolds stresses and turbulence production decreased dramatically with increasing frequency up to the shear layer frequency (= 14), but further excitation (= 58) resulted in a regain of turbulence levels. Proper orthogonal decomposition (POD) was performed which showed that the low frequency operations globally affect the modes in the shear layer while the high frequency operations are confined to the airfoil surface.The authors would like to acknowledge support from the Natural Sciences and Engineering Research Council of Canada and CMC Microsystems. Computations were performed at the SciNet HPC Consortium. SciNet is funded by the Canada Foundation for Innovation under the auspices of Compute Canada, the Government of Ontario, Ontario Research Fund - Research Excellence, and the University of Toronto. SOSCIP is funded by the Federal Economic Development Agency of Southern Ontario, IBM Canada, Ltd., Ontario Centres of Excellence, Mitacs, and academic member institutions. The authors thank Dr. Mark Feero for the data
Focusing Ultrasound to the Vertebral Canal
The blood spinal cord barrier (BSCB) and blood brain barrier (BBB) are semi-permeable barriers separating the spinal cord and brain vasculature from the parenchyma. Focused ultrasound can transiently open the BBB to improve therapeutic agent delivery to the brain. The extension of this technique to the human BSCB may similarly improve targeted therapies to the spinal cord. However, focusing ultrasound to the spinal cord is difficult because it is encased in the spine, which consists of stacked, irregularly shaped vertebrae that distort the intended foci. This thesis aimed to develop a spine-specific ultrasound array and simulation-based aberration correction method to generate a controlled focus in the intact vertebral canal. A spine-specific formulation of a multi-layered ray acoustics model was developed, and its accuracy characterized through comparison with set of 90 field measurements produced with a spherically focused 514kHz transducer. This model predicted maximum pressure locations and weighted focal volume locations with an accuracy of 2.3mm and 1.5mm respectively. The ray acoustics model was then used to optimize a vertebra-specific density (rho) - speed of sound (cL) function to maximize the model accuracy in calculating vertebra-induced time delays. A linear model was optimized in this work, cL(rho) = 0.35(rho - rho_w) + cL_w (w denotes water), which was able to reproduce the vertebra-induced delays with an accuracy of lambda/16, where lambda is the wavelength. The ray acoustics model was used to optimize the design of a spine-specific ultrasound phased array for maximum efficiency in focusing ultrasound through the posterior elements of the spine. The optimized array had four quadrants, two 64-element arrays for focusing ultrasound through the vertebra laminae, and two 64-element arrays for focusing ultrasound through the paravertebral spaces. One array quadrant was built and used to demonstrate transspine beamforming with geometric delays, hydrophone-based delays, and delays calculated with the ray acoustics model. The ray acoustics delays outperformed the geometric delays, but not the hydrophone-based delays. Demonstrating the feasibility of ultrasound array-based focusing through the spine is a critical step to advancing ultrasound treatments of the spinal cord.Ph.D
Common variants in breast cancer risk loci predispose to distinct tumor subtypes
Abstract
Background
Genome-wide association studies (GWAS) have identified multiple common breast cancer susceptibility variants. Many of these variants have differential associations by estrogen receptor (ER) status, but how these variants relate with other tumor features and intrinsic molecular subtypes is unclear.
Methods
Among 106,571 invasive breast cancer cases and 95,762 controls of European ancestry with data on 173 breast cancer variants identified in previous GWAS, we used novel two-stage polytomous logistic regression models to evaluate variants in relation to multiple tumor features (ER, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and grade) adjusting for each other, and to intrinsic-like subtypes.
Results
Eighty-five of 173 variants were associated with at least one tumor feature (false discovery rate < 5%), most commonly ER and grade, followed by PR and HER2. Models for intrinsic-like subtypes found nearly all of these variants (83 of 85) associated at p < 0.05 with risk for at least one luminal-like subtype, and approximately half (41 of 85) of the variants were associated with risk of at least one non-luminal subtype, including 32 variants associated with triple-negative (TN) disease. Ten variants were associated with risk of all subtypes in different magnitude. Five variants were associated with risk of luminal A-like and TN subtypes in opposite directions.
Conclusion
This report demonstrates a high level of complexity in the etiology heterogeneity of breast cancer susceptibility variants and can inform investigations of subtype-specific risk prediction
Intersectional inequalities in younger women’s experiences of physical intimate partner violence across communities in Bangladesh
Abstract
Background
Physical intimate partner violence (IPV) risk looms large for younger women in Bangladesh. We are, however, yet to know the association between their intersectional social locations and IPV across communities. Drawing on intersectionality theory’s tenet that interacting systems of power, oppressions, and privileges work together, we hypothesized that (1) younger, lower educated or poor women’s physical IPV experiences will be exacerbated in disadvantaged communities; and conversely, (2) younger, higher educated or nonpoor women’s physical IPV experiences will be ameliorated in advantaged communities.
Methods
We applied intercategorical intersectionality analyses using multilevel logistic regression models in 15,421 currently married women across 911 communities from a national, cross-sectional survey in 2015. To test the hypotheses, women’s probabilities of currently experiencing physical IPV among intersectional social groups were compared. These comparisons were made, at first, within each type of disadvantaged (e.g., younger or poor) and advantaged (e.g., older or nonpoor) communities; and then, between different types of communities.
Results
While our specific hypotheses were not supported, we found significant within community differences, suggesting that younger, lower educated or poor women were bearing the brunt of IPV in almost every community (probabilities ranged from 34.0–37.1%). Younger, poor compared to older, nonpoor women had significantly higher IPV probabilities (the minimum difference = 12.7, 95% CI, 2.8, 22.6) in all communities. Similar trend was observed between younger, lower educated compared to older, higher educated women in all except communities that were poor. Interestingly, younger women’s advantage of higher education and material resources compared to their lower educated or poor counterparts was observed only in advantaged communities. However, these within community differences did not vary between disadvantaged and advantaged communities (difference-in-differences ranged from − 0.9%, (95% CI, − 8.5, 6.7) to − 8.6%, (95% CI, − 17.6, 0.5).
Conclusions
Using intersectionality theory made visible the IPV precarity of younger, lower educated or poor women across communities. Future research might examine the structures and processes that put them at these precarious locations to ameliorate their socio-economic-educational inequalities and reduce IPV in all communities. For testing hypotheses using intersectionality theory, this study might advance scholarship on physical IPV in Bangladesh and quantitative intersectionality globally
Cardiac Magnetic Resonance Left Ventricle Segmentation and Function Evaluation Using a Trained Deep-Learning Model
Cardiac MRI is the gold standard for evaluating left ventricular myocardial mass (LVMM), end-systolic volume (LVESV), end-diastolic volume (LVEDV), stroke volume (LVSV), and ejection fraction (LVEF). Deep convolutional neural networks (CNNs) can provide automatic segmentation of LV myocardium (LVF) and blood cavity (LVC) and quantification of LV function; however, the performance is typically degraded when applied to new datasets. A 2D U-net with Monte-Carlo dropout was trained on 45 cine MR images and the model was used to segment 10 subjects from the ACDC dataset. The initial segmentations were post-processed using a continuous kernel-cut method. The refined segmentations were employed to update the trained model. This procedure was iterated several times and the final updated U-net model was used to segment the remaining 90 ACDC subjects. Algorithm and manual segmentations were compared using Dice coefficient (DSC) and average surface distance in a symmetric manner (ASSD). The relationships between algorithm and manual LV indices were evaluated using Pearson correlation coefficient (r), Bland-Altman analyses, and paired t-tests. Direct application of the pre-trained model yielded DSC of 0.74 ± 0.12 for LVM and 0.87 ± 0.12 for LVC. After fine-tuning, DSC was 0.81 ± 0.09 for LVM and 0.90 ± 0.09 for LVC. Algorithm LV function measurements were strongly correlated with manual analyses (r = 0.86–0.99, p < 0.0001) with minimal biases of −8.8 g for LVMM, −0.9 mL for LVEDV, −0.2 mL for LVESV, −0.7 mL for LVSV, and −0.6% for LVEF. The procedure required ∼12 min for fine-tuning and approximately 1 s to contour a new image on a Linux (Ubuntu 14.02) desktop (Inter(R) CPU i7-7770, 4.2 GHz, 16 GB RAM) with a GPU (GeForce, GTX TITAN X, 12 GB Memory). This approach provides a way to incorporate a trained CNN to segment and quantify previously unseen cardiac MR datasets without needing manual annotation of the unseen datasets
Docile Minds: Discursive Implications of Mental Health Policies Related to Young People in Ontario
This study investigated how administrative interests impact understandings of youth mental health in Ontario’s public education system. Drawing on Michel Foucault’s model of Administrative Control as a theoretical framework and Norman Fairclough’s five-stage method of Critical Discourse Analysis (CDA) as a research methodology, this report examined seven (7) policy documents released between 2011 and 2015. These documents include the Ontario secondary school Health and Physical Education curriculum document, two provincial policy documents, a report commissioned by an independent charitable organization, an online resource hosted by a children’s mental health centre, a report commissioned by a national non-profit organization, and a public school board implementation plan. Results of the study revealed a powerful underlying interest in Administrative Control that presents systemic barriers to the development of positive student mental health outcomes. Discursive constructions of youth mental health in Ontario were found to associate mental health with a set of adverse clinical outcomes to be monitored and reported. More specifically, existing discourses were found to (a) prioritize clinical approaches to addressing adverse individual outcomes over developmental approaches to promoting psychological resilience, (b) call for sweeping normalization, to promote simplistic notions of risk and protection, (c) discursively appropriate the concept of mental health through collectivization, and to exclude the role of challenge as a developmental tool. Instead, this study suggests that mental health should be reframed within the context of public education policies as an ongoing developmental process of adjustment to a range of environmental factors. Finally, this study recommends the application of psychological resilience, academic resilience, and academic buoyancy as underlying constructs in the development of future school mental health policies. This study contributes to ongoing discussions about the role of discourse in both reflecting and shaping mental health outcomes among young people in Ontario.Ed.D
Conserved Molecular Signatures in the Spike, Nucleocapsid, and Polymerase Proteins Specific for the Genus Betacoronavirus and Its Different Subgenera
The genus Betacoronavirus, consisting of four main subgenera (Embecovirus, Merbecovirus, Nobecovirus, and Sarbecovirus), encompasses all clinically significant coronaviruses (CoVs), including SARS, MERS, and the SARS-CoV-2 virus responsible for current COVID-19 pandemic. Very few molecular characteristics are known that are specific for the genus Betacoronavirus or its different subgenera. In this study, our analyses of the sequences of four essential proteins of CoVs, viz., spike, nucleocapsid, envelope, and RNA-dependent RNA polymerase (RdRp), identified ten novel molecular signatures consisting of conserved signature indels (CSIs) in these proteins which are specific for the genus Betacoronavirus or its subgenera. Of these CSIs, two 14-aa-conserved deletions found within the heptad repeat motifs 1 and 2 of the spike protein are specific for all betacoronaviruses, except for their shared presence in the highly infectious avian coronavirus. Six additional CSIs present in the nucleocapsid protein and one CSI in the RdRp protein are distinctive characteristics of either the Merbecovirus, Nobecovirus, or Sarbecovirus subgenera. In addition, a 4-aa insert is present in the spike protein, which is uniquely shared by all viruses from the subgenera Merbecovirus, Nobecovirus, and Sarbecovirus, but absent in Embecovirus and all other genera of CoVs. This molecular signature provides evidence that viruses from the three subgenera sharing this CSI are more closely related to each other, and they evolved after the divergence of embecoviruses and other CoVs. As all CSIs specific for different groups of CoVs are flanked by conserved regions, their sequences provide novel means for identifying the above groups of CoVs and for developing novel diagnostic tests. Furthermore, our analyses of the structures of the spike and nucleocapsid proteins show that all identified CSIs are localized in the surface-exposed loops of these protein. It is postulated that these surface loops, through their interactions with other cellular proteins/ligands, play important roles in the biology/pathology of these viruses
Impaired Proteostasis in Obese Skeletal Muscle Relates to Altered Immunoproteasome Activity
Obesity-associated inflammation and/or oxidative stress can damage intramuscular proteins and jeopardize muscle integrity. The immunoproteasome (iProt) is vital to remove oxidatively modified proteins, but this function may be compromised with obesity. We sought to elucidate whether diet-induced obesity (DIO) alters intramuscular iProt content and activity in mice to identify a possible mechanism for impaired muscle proteostasis in the obese state. Total proteasome content and activity and estimates of muscle oxidative damage, inflammation, muscle mass and strength were also assessed. Twenty-three male, 5-week-old C57BL/6J mice were fed a high-fat, high-sucrose (HFS, 45% kcal fat, 17% sucrose, n = 12) or low-fat, low-sucrose (LFS, 10% kcal fat, 0% sucrose, n = 11) diet for 12 weeks. Strength was assessed via a weightlifting test. Despite no change in pro-inflammatory cytokines (P > 0.05), oxidative protein damage was elevated within the gastrocnemius (P = 0.036) and tibialis anterior (P = 0.033) muscles of HFS-fed mice. Intramuscular protein damage coincided with reduced iProt and total proteasome activity (PThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
Investigating frontline service provider burnout : working with youth victims and perpetrators of inappropriate sexual behaviours
This research paper was completed and submitted at Nipissing University, and is made freely accessible through the University of Toronto’s TSpace repositoryFrontline service providers (FSP) working with youth victims and perpetrators of inappropriate sexual behaviours (ISB) are working in high stress positions. Researchers have demonstrated FSP experience burnout symptoms related to their work, including emotional and physical exhaustion, depersonalization, and feelings of reduced personal accomplishment. However, very few researchers have compared the experiences of burnout between those working with youth victims and youth perpetrators of ISB. Therefore, this study aims to fill the gap of the existing literature. The proposed study investigates the experiences of burnout within FSP working with youth who are victims and perpetrators of ISB. This detailed literature review includes both qualitative and quantitative research to describe burnout while differentiating burnout from similar work stress conditions, the experiences of burnout of FSP in various occupations including policing, social work and mental health fields, and the challenges associated with researching burnout. Results show confounding definitions of burnout throughout disciplines confusing the research and results. Burnout symptoms have been reported in both FSP working with adult sex offenders and youth perpetrators and victims of ISB. It is seen that the experience of the FSP, age of FSP, environment in which FSP work, and the sex of the FSP have shown to influence particular FSP populations, though it is unclear if this includes those working with youth engaging in ISB. Further investigations are required to identify possible influences of burnout, as well as an overarching and accurate definition of burnout for future study