Publications by authors named "Simon Warner"

People with amblyopia show deficits in global motion perception, especially at slow speeds. These observers are also known to have unstable fixation when viewing stationary fixation targets, relative to healthy controls. It is possible that poor fixation stability during motion viewing interferes with the fidelity of the input to motion-sensitive neurons in visual cortex.

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For more than 60 years, efforts to develop mating-based mosquito control technologies have largely failed to produce solutions that are both effective and scalable, keeping them out of reach of most governments and communities in disease-impacted regions globally. High pest suppression levels in trials have yet to fully translate into broad and effective control solutions. Two primary challenges to date-the need for complex sex-sorting to prevent female releases, and cumbersome processes for rearing and releasing male adult mosquitoes-present significant barriers for existing methods.

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Background: The fall armyworm, Spodoptera frugiperda, is a significant and widespread pest of maize, sorghum, rice, and other economically important crops. Successful management of this caterpillar pest has historically relied upon application of synthetic insecticides and through cultivation of genetically engineered crops expressing insecticidal proteins (Bt crops). Fall armyworm has, however, developed resistance to both synthetic insecticides and Bt crops, which risks undermining the benefits delivered by these important crop protection tools.

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Precis: The peripapillary choriocapillaris (CC) was observed to be significantly impaired in normal tension glaucoma (NTG) subjects compared with normal controls using optical coherence tomography angiography (OCTA).

Purpose: The aim was to quantitatively evaluate the peripapillary CC in NTG, primary open-angle glaucoma (POAG), and control eyes using OCTA.

Materials And Methods: Ninety eyes (30 controls, 30 NTG, and 30 POAG) from 73 patients were imaged using the Zeiss Plex Elite 9000.

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Purpose: To evaluate the role of ensemble learning techniques with deep learning in classifying diabetic retinopathy (DR) in optical coherence tomography angiography (OCTA) images and their corresponding co-registered structural images.

Methods: A total of 463 volumes from 380 eyes were acquired using the 3 × 3-mm OCTA protocol on the Zeiss Plex Elite system. Enface images of the superficial and deep capillary plexus were exported from both the optical coherence tomography and OCTA data.

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Objective: To characterize the trends and explore the demographics, ophthalmic manifestations, and outcomes of ocular syphilis cases in British Columbia.

Design: Retrospective chart review.

Participants: Ocular syphilis cases reported to the British Columbia Centre for Disease Control (BCCDC) between January 2013 and December 2016.

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Objective: This study was conducted to analyse data from emergency ophthalmology referrals after-hours from different hospitals to identify the most common pathologies and compare accuracy of diagnoses. The primary objective was to identify common presenting entities and common causes of misdiagnosis in the emergency department to help guide education initiatives.

Design: This was a retrospective chart review that looked at consults occurring between September 1, 2015, and October 21, 2016.

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Objective: This study was conducted to analyze data from emergency ophthalmology referrals after hours from different hospitals to identify the most common pathologies and compare accuracy of diagnoses. Additionally, examination findings, including visual acuity (VA), intraocular pressure (IOP), and pupils from referring service and ophthalmic examination, were compared to assess agreement.

Design: This was a prospective study that reviewed information collected from referring services to the emergency on-call ophthalmology service and compared it with ophthalmic examination between February 2017 and July 2017.

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Objective: To describe the clinical presentation and genotype of subjects with aniridia with a particular focus on foveal hypoplasia.

Design: Prospective cohort study.

Participants: Thirty-three Canadian participants with aniridia and of various ethnic backgrounds residing in British Columbia.

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Bactrocera oleae (Diptera: Tephritidae) remains a major pest of olive fruit production worldwide. Current pest management programs largely depend on chemical insecticides, resulting in high economic and environmental costs. Alternative pest control approaches are therefore highly desirable.

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Purpose: To examine the association between open-angle glaucoma and erectile dysfunction (ED), and investigate the correlation in severity between these 2 conditions.

Methods: Cross-sectional study with patient questionnaire and retrospective chart review. A total of 167 male patients over 40 years of age who attended ophthalmology clinic visits in Vancouver, British Columbia, Canada, participated in the study by providing written consent and responding to the survey.

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A 47-year-old man with recent travel to the Caribbean was admitted with acute febrileillness associated with arthralgia and skin rash followed by sudden onset of bilateral visual field defects. Funduscopy revealed subtle bilateral paracentral dark lesions nasal to the fovea best seen on near infrared imaging as hyporeflective, wedge-shaped, paracentral macular lesions. Spectral-domain optical coherence tomography (SD-OCT) through the lesions revealed hyperreflective bands at the level of the outer plexiform layer and outer nuclear layer (ONL), with concomitant attenuation of the underlying external limiting membrane (ELM), ellipsoid zone (EZ), and interdigitation zone (IZ).

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Background: Aedes aegypti is the primary vector of dengue fever, a viral disease which has an estimated incidence of 390 million infections annually. Conventional vector control methods have been unable to curb the transmission of the disease. We have previously reported a novel method of vector control using a tetracycline repressible self-limiting strain of Ae.

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Background: Development and evaluation of new insect pest management tools is critical for overcoming over-reliance upon, and growing resistance to, synthetic, biological and plant-expressed insecticides. For transgenic crops expressing insecticidal proteins from the bacterium Bacillus thuringiensis ('Bt crops') emergence of resistance is slowed by maintaining a proportion of the crop as non-Bt varieties, which produce pest insects unselected for resistance. While this strategy has been largely successful, multiple cases of Bt resistance have now been reported.

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Purpose: To determine whether pseudoexfoliation (PEX) syndrome is associated with an increased risk of chronic kidney disease (CKD).

Patients And Methods: In this cross-sectional study, 271 consecutive patients were recruited into 3 study groups---PEX syndrome (n=86), primary open-angle glaucoma (POAG) (n=91), and nonglaucoma controls (n=94)---and underwent serum creatinine testing to determine their glomerular filtration rates (eGFR). Repeat eGFR and testing for urine albumin:creatinine ratio were performed a minimum of 3 months later if the initial eGFR was less than 60 mL/min/1.

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Purpose: To determine the frequency of exposure to Helicobacter pylori infection in glaucoma patients.

Design: Prospective case-control study.

Participants: Ninety-seven consecutive patients attending a glaucoma clinic.

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