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A linear spline maximum entropy method for Frobenius-Perron operators of multi-dimensional transformations
No full textA piecewise linear spline maximum entropy optimization method is described for the approximation of fixed densities of the Frobenius-Perron operator associated with higher-dimensional transformations. Convergence in 1-norm is proved and several examples with results are given.NSERC D
The effects of berry polyphenols on the gut microbiota and blood pressure: A systematic review of randomized clinical trials in humans
No full textBerry consumption has beneficial effects on blood pressure. Intestinal microbiota transform berry phytochemicals into more bioactive forms. Thus, we performed a systematic review of randomized clinical trials to determine whether berry polyphenols in foods, extracts or supplements have effects on both the profile of gut microbiota and systolic and diastolic blood pressure in humans. PubMed, Cochrane Library, Scopus, and CAB Abstracts (EBSCOhost) were searched for randomized clinical trials in humans published from 1 January 2011 to 29 October 2021. Search results were imported into Covidence for screening and data extraction by two blinded reviewers, who also performed bias assessment independently. The literature search identified 216 publications; after duplicates were removed, 168 publications were screened with 12 full-text publications assessed for eligibility. Ultimately three randomized clinical trials in humans met the eligibility criteria. One randomized clinical trial showed a low risk of bias while the other two randomized clinical trials included low, high or unclear risk of bias. Together the randomized clinical trials showed that berry consumption (Aronia berry, strawberries, raspberries, cloudberries and bilberries) for 8–12 weeks had no significant effect on both blood pressure and the gut microbiota. More randomized clinical trials are needed to determine the effects of berry consumption on the profile of gut microbiota and blood pressure in humans
Nitrogen Oxide (NOx) emissions as an indicator for sustainability
No full textEnvironmental data and research illustrate that global warming, normally assessed through carbon dioxide (CO2) and greenhouse gas (GHG) emissions, is a critical element in environmental sustainability and that a shift to decarbonized energy sources is necessary to preserve the environment for future generations. The challenge is that overall global sustainability is more complex than solely focusing on global warming or the environment.
As a potential alternative, NOx emissions are explored as a potential surrogate for CO2 and GHG emissions and as an indicator for decarbonization. An added benefit of using NOx is that it has strong correlations with each pillar of sustainability, and therefore can offer a more encompassing view. Global and country specific NOx emissions, between 1990 and 2015, are analyzed in a format paralleling the three pillars. Trends show that, while NOx emissions are increasing, there are improvements in both societal and economic emission intensities. It is also demonstrated that there is no net movement towards decarbonization, and that a paradigm shift will be necessary to achieve the emissions reductions required. As well, human development index appears to be tied to the change in per capita emissions of NOx over the study period. Overall, NOx is demonstrated to be a robust and potentially more effective surrogate for CO2 and GHG emissions in estimating fossil fuel emissions and gauging movement towards decarbonization. The added interconnectedness of NOx with all three pillars makes it an excellent indicator for tracking progress towards overall sustainability
Evaluation of cameras and image distance for CNN-based weed detection in wild blueberry
No full textAgricultural herbicide application efficiency can be improved using smart sprayers which provide site-specific, rather than broadcast, applications of agrochemicals. The YOLOv3-Tiny convolutional neural network (CNN) was trained to detect two weeds, hair fescue and sheep sorrel, in images captured from wild blueberry fields throughout Nova Scotia, Canada. An evaluation was performed in three commercial wild blueberry fields in Nova Scotia to examine the effects of camera selection and target distance on detection accuracy. A Canon T6 DSLR camera, an LG G6 smartphone, and a Logitech c920 webcam were used to capture RGB images at varying distances from target weeds. Mean F1-scores for each combination of camera and image height were analysed in a 3 × 3 factorial arrangement for hair fescue and a 3 × 2 factorial arrangement for sheep sorrel. Images captured from 0.98 m with the LG G6 and Canon T6 produced F1-scores of up to 0.97 for detection of at least one hair fescue tuft. Images captured with the LG G6 and Canon T6 DSLR from 0.57 m achieved F1-scores of 0.94 and 0.93, respectively, for detection of at least one sheep sorrel plant per image. Sheep sorrel was undetectable in images from the Logitech c920 under 19 of 27 parameter combinations. Future work will involve using the CNN to control herbicide applications with a real-time smart sprayer. Additionally, the CNN will be used in a web-based application to detect target weeds and provide site-specific information to aid management decisions. Using a CNN to detect weeds will create improvements in management techniques, resulting in cost-savings and greater sustainability for the wild blueberry industry
The journey to fatherhood following an experience of infertility
No full textFathers who endure infertility are an important part of the family unit and require support. Despite this awareness, there is a limited understanding of fathers’ lived experience during the perinatal period following infertility. The purpose of this descriptive, phenomenological study was to explore fathers’ lived experiences throughout the perinatal period following an experience of infertility. Colaizzi’s (1978) method guided this study. After obtaining ethics approval, a purposive sample of 8 fathers who met the eligibility criteria were recruited. Informed, written consent was obtained from all participants. One-on-one interviews were held in person, by telephone, and via virtual platforms. The audio-taped interviews were transcribed verbatim and analyzed using Colaizzi’s method. Seven themes uncovered the lived experience of fathers. They included a) The Journey: A Long Winding Road, b) Roles and Responsibilities: The Supporter, c) Support: The Often-Forgotten Parent, d) Challenges/Hurdles: Bumps on the Road, e) So Many Feelings: The Rollercoaster, f) Coping: Living on the Road, and g) Reflection: An Unforgotten Journey. Fathers shared their experiences of a long journey and how bumps along the road marked their journeys. Their journeys were essential parts of their lives that they continued to remember years later. They shed light on how important it is to involve them in the perinatal process to facilitate positive experiences and overall family health. They also demonstrated an ongoing need for research that involves fathers and the development of programming to help them through the perinatal period following an experience of infertility
Description of biosecurity practices on shrimp farms in Java, Lampung, and Banyuwangi, Indonesia
No full textThe sustainability of the Indonesian shrimp farming industry is challenged by the presence of bacterial and viral diseases and their associated potential for severe economic losses and environmental impact. In shrimp aquaculture, biosecurity is essential to prevent pathogen introduction, emergence and spread within and between farms. This study was undertaken (1) to design and implement a questionnaire survey addressing key shrimp aquaculture management and biosecurity practices, and (2) to provide an overview and patterns of the current state of biosecurity for grow-out and intensive shrimp farms in Indonesia. A questionnaire was designed to collect information on farm characteristics, farm management, and biosecurity practices. Descriptive statistics, multiple correspondence analyses, and hierarchical clustering were used to summarize and identify patterns of biosecurity practices implemented by farmers and to classify farms into different clusters, based on these practices. Three distinct clusters were identified for 96 grow-out farms in Java and Lampung area, while 7 clusters were identified for 101 intensive farms in Banyuwangi area. For Java and Lampung, 2 clusters were mostly characterized by micro and small-scale farms, with less intense biosecurity practices, including not testing seed quality, not disinfecting people, vehicles, or equipment, not removing dead animals. One cluster was best represented by medium and large-scale farms applying higher intensity biosecurity practices, including greater distance to neighboring farms, disinfection for visitors, vehicles, and staff, testing seed quality, and fallow period greater than 30 days between cycles. In Banyuwangi area, farms could not be distinctly classified into clusters by patterns of biosecurity practices but were defined more by farm management and characteristics of the data structure (e.g., lack of response or missing records). For future sustainable surveillance programs and biosecurity implementation to reduce the risk of disease introduction and spread in these regions, recommendations include: training for improved, transparent, and consistent record-keeping; focusing future data collection on cluster or region-specific priorities and disease-specific biosecurity approaches by farming method (e.g., for intensive vs. grow-out); and increasing evidence-based decisions using epidemiological knowledge developed within industry, government, and shrimp aquaculture farmers.IDH FIT Fund ProjectsJala Tech Pte. Ltd
First report of Angiostrongylus vasorum (French heartworm) in red foxes (Vulpes vulpes) on Prince Edward Island
No full textObjective: To identify first-stage nematode larvae (L1) recovered from a red fox scat sample and adult female worms recovered from 2 red fox lungs at necropsy, using published molecular methods to confirm a morphological diagnosis of Angiostrongylus vasorum (French heartworm).
Animal: Red fox (Vulpes vulpes).
Procedure: Nematode larvae recovered from a Baermann examination survey of wild canid scats (n = 101) conducted from January 2017 to August 2020, were identified by size and morphology and subjected to PCR and DNA sequencing of the small subunit (SSU) rRNA gene, the large subunit (LSU) rRNA gene, or the second internal transcribed spacer (ITS2). In addition, these techniques were applied to adult female worms recovered from the heart/lungs of 2 red foxes (obtained from PEI trappers and stored frozen at -20°C since December of 2018 and 2020).
Results: Size and morphology of L1 recovered by Baermann examination from a wild canid scat sample (presumed to be red fox) collected near Montague, PEI and adult female worms recovered at necropsy from 2 red fox carcasses were identified as A. vasorum. Molecular analysis confirmed the larvae and adult worms were A. vasorum.
Conclusion: These findings indicated that A. vasorum has become endemic in the red fox population on PEI.
Clinical relevance: Angiostrongylus vasorum infection is potentially fatal in dogs. Veterinarians and regional diagnostic laboratories in the Maritime provinces should consider the possibility of A. vasorum infection in dogs with clinical signs of cardiopulmonary and/or central nervous system disease or bleeding disorders.journal article2022 Junimporte
Development of an attitude control system for CubeSat application
No full textGuidance, navigation, and control (GNC) systems are commonly found in vehicles, whether they be spacecraft, aircraft, seacraft or landcraft. These systems are designed to bring the vehicle to its desired position and/or orientation by sensing pose and making the necessary adjustments to onboard devices. With regard to satellites, GNC systems are divided into two segments: orbit control, which is concerned with the spacecraft’s position, and attitude control, which is concerned with the spacecraft’s orientation. The focus of this thesis is to develop the attitude control system of a CubeSat nanosatellite being designed for the University of Prince Edward Island’s SpudNik-1 mission.
The objective of this study was to progress the design of the attitude control system (ACS) from its conceptual design phase to a state where it is ready for assembly, integration, and testing. To accomplish this, the engineering design process was applied. Accordingly, the fundamentals of attitude control were first reviewed in literature. Then, the system-level requirements were evaluated and the current design’s ability to meet them was assessed. After doing so, the necessary alterations were made to the conceptual design, such that it would meet the requirements, and the various methods of requirement verification were defined to verify that this is the case during the assembly, integration, and testing phase. Once the system-level design had been established, this process was repeated for the subsystem- and unit-level designs.
In addition to contributing the detailed design of an attitude control system to the Spudnik-1 team, this work can also serve as a reference for other teams working toward space missions that require the use of an ACS by providing a comprehensive perspective that focuses on the identification, integration, and implementation of the major elements of an attitude control system. It not only offers detailed information on the definition, measurement, modeling, estimation, and control of a spacecraft’s attitude, but also identifies: the connections between these concepts; the hardware used to implement the concepts in a real-world application; and the various considerations that should be taken during this implementation.
Aside from familiarizing the reader with the methodology behind an ACS system, this work also describes the procedure that was used to develop the attitude control subsystem of the SpudNik-1 CubeSat. It details: how the requirements of the attitude control subsystem were identified from the spacecraft’s mission and the corresponding system requirements; how the major components and concepts of the ACS are identified from the subsystem requirements, and integrated through the subsystem architecture; how the unit-level requirements are identified based on the subsystem-level design; and how the implementation of the various components and concepts is dependent on the unit level requirements.
While a good deal of the design is standard with regard to CubeSats and other aerospace projects, the original aspects would relate to the in-house design of the reaction wheels and fine sun sensors. Being as there are a wide selection of ACS components available on the market, it is most common for CubeSat projects to procure their hardware. Although the lack of flight heritage did pose additional risk to the mission in comparison to using commercial equipment, the in-house design allowed the components to be both tailored to the mission and produced at a fraction of the cost. If the designs manage to gain flight heritage on-board of the SpudNik-1 CubeSat, then this work will provide readers with standard frameworks which will allow them to reap the same benefits, but at a lower level of risk
Subtract? That’s a math word! Unpacking teachers’ language choices in preschool and kindergarten classrooms
No full textEven though a substantial body of research suggests that adults’ math talk fosters children’s mathematics development and willingness to learn mathematics, little is known about how teachers make pedagogical decisions to communicate mathematics to young students. Supported by socio-constructivist and semiotic lenses, the study focuses on the close interactions between teachers and their students to better understand the educators’ perspectives and the rationale for their mathematical pedagogies when communicating and mediating number sense to young students. An instrumental case study approach and discourse analysis were utilized to investigate how a cultural tool, mathematics, was communicated and mediated to preschool and kindergarten students. Findings indicated that participants focused on supporting young students’ meaning-making processes before teaching language form. This pedagogical choice resulted in educators creating a particular early year’s mathematical discourse grounded in the avoidance of nouns and in the use of terms that students knew, verbs, and terms that denoted actions.Social Sciences and Humanities Research Council (SSHRC) of Canad
Characteristics of Canadian Veterans reimbursed for cannabis for medical purposes: Life After Service Survey 2016
No full textIntroduction: Cannabis is used to self-treat a wide range of symptoms and conditions. However, there is scarce information describing the characteristics of Canadian Veterans being reimbursed by Veterans Affairs Canada (VAC) for
cannabis used for medical purposes (CMP). The objective of this study was to explore the demographic and military
service characteristics and chronic conditions associated with CMP reimbursement of VAC clients responding to the
2016 Life After Service Survey (LASS). Methods: This study linked the VAC reimbursement information for CMP
and data from the 2016 LASS. In total, 1,480 LASS survey participants were VAC clients and were included in this
study. Both descriptive and bivariate analyses were performed to explore the population characteristics (46 demographic, military, and well-being variables) associated with CMP reimbursement. Results: Of the 1,480 VAC clients in this
study, 72 were reimbursed for CMP. Of the 46 variables, 20 were significant. Several variables from different domains
were associated with CMP reimbursement in the bivariate analysis: anxiety, posttraumatic stress disorder, depression,
bowel ulcer, traumatic brain injury, chronic pain, 12-Item Short Form Survey (SF-12) scores, psychological distress, suicidal ideation, requiring help with tasks, financial status, unemployment, low income, dissatisfaction with finances, and
satisfaction with family members. Discussion: These results provide preliminary information on Canadian Veterans
reimbursed for CMP. Further studies that can identify larger numbers of Veterans reimbursed for CMP are needed to
further explore these characteristics with multivariate approaches