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Design and Synthesis of Custom Styryl BODIPY Dyes for Bimodal Imaging
Get PDFInnovation towards new agents for combined positron emission tomography/optical imaging is of significance for making advances in patient diagnosis. As of recent, boron-dipyrromethene (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene, BODIPY) dyes have shown promise as bimodal imaging agents serving as a fluorescent tag with capability to act as a fluorine-18 radiotracer. However, due the sensitivity of these molecules their chemical transformations are poorly understood. In this thesis, I address the synthetic challenge of near-infrared, “clickable” BODIPY dyes with complex functionality in order to identify reliable syntheses.
Early investigation was concentrated on understanding the intricacies of BODIPY synthesis; in particular, the low yielding incorporation of boron difluoride. Conventional one-pot procedures were revised, and it was found that isolating the dipyrromethene scaffold followed by boron complexation improved the yield overall. In addition, aqueous work up procedures were modified to avoid the decomplexation of boron difluoride from the BODIPY product by vacuum-assisted removal of excess boron trifluoride. Robust synthetic procedures were established to afford the azido- functionalized BODIPY, which is valuable for tagging novel BODIPY dyes to disease-targeting vectors using “Click Chemistry”.
The latter of the thesis focused on improving the water-solubility of the conjugated BODIPY dyes by addition of ionizable groups which can also partake in hydrogen bonding, making them suitable for biological application. It was found that the BODIPY molecule could not withstand ester hydrolysis conditions needed to produce diacid BODIPY derivatives. Alternatively, a Knoevenagel-like condensation provided two near-infrared BODIPY dyes, one bearing dihydroxy (phenolic) functionality demonstrating partial water-solubility. The dyes were characterized as long wavelength dyes to compliment future Price group studies
DIGITAL TOOLS FOR DELIVERY OF DEMENTIA EDUCATION: INCREASING RURAL ACCESSIBILITY FOR DEMENTIA CARE
Get PDFThis dissertation contributes to knowledge on digital and remote methods of dementia education, which are methods that are accessible for rural residents. Education for informal caregivers (who are typically unpaid family members) may improve caregiver well being, increase self-efficacy in caregiving, and prolong time at home for persons with dementia, and remote methods make this education accessible for rural dwelling families. Similarly, rural primary care professionals face challenges in dementia care related to unique aspects of rural living, such as work isolation and reduced access to specialized services and learning opportunities. Provision of continued education to primary care practitioners plays a vital role in improving patient care by reducing knowledge disparities and diagnostic doubt, thereby assisting patients in receiving a timely diagnosis. Over the course of the first two studies, the dissertation will develop an evidence-based delivery strategy for evaluating digitally-delivered dementia education for informal caregivers and rural primary care providers, which that is feasible and acceptable. This evidence will serve as a foundation for the third study, a pilot study for rural primary care providers.
Study 1 investigates and documents technology-based modes of remote dementia education for informal caregivers via a systematic review and meta-analysis of the impact on caregivers based on the intervention literature. Study 2 investigates and documents technology-based modes of remote dementia education for healthcare providers via a systematic review, which is used to inform the third study. Study 3 explores feasibility and acceptability of dementia education delivered via a smart phone application with selective reminding (research has shown that education can be enhanced with intermittent prompts to boost use of newly acquired concepts in everyday practice). We postulate that this form of remote education will be flexible (i.e., able to be distributed over shorter time intervals), tailored to care provider needs, and highly accessible.
The dissertation findings will determine a model of dementia education best suited to the needs of rural caregivers (informal and formal) and will be used to determine next steps in developing and piloting of an educational program aimed at the understudied population of rural primary care providers
Optimized hardware implementations of cryptography algorithms for resource-constraint IoT devices and high-speed applications
Get PDFThe advent of technologies, including the Internet and smartphones, has made people’s lives easier. Nowadays, people get used to digital applications for e-business, communicating with others, and sending or receiving sensitive messages. Sending secure data across the private network or the Internet is an open concern for every person. Cryptography plays an important role in privacy, security, and confidentiality against adversaries. Public-key cryptography (PKC) is one of the cryptography techniques that provides security over a large network, such as the Internet of Things (IoT).
The classical PKCs, such as Elliptic Curve Cryptography (ECC) and Rivest-Shamir-Adleman (RSA), are based on the hardness of certain number theoretic problems. According to Shor’s algorithm, these algorithms can be solved very efficiently on a quantum computer, and cryptography algorithms will be insecure and weak as quantum computers increase in number. Based on NIST, Lattice-based cryptography (LBC) is one of the accepted quantum-resistant public-key cryptography. Different variants of LBC include Learning With Error (LWE), Ring Learning With Error (Ring-LWE), Binary Ring Learning with Error (Ring-Bin LWE), and etc. AES is also one of the secure cryptography algorithm that has been widely used in different applications and platforms. Also, AES-256 is secure against quantum attack.
It is very important to design a crypto-system based on the need and application. In general, each network has three different layers; cloud, edge, and end-node. The cloud and edge layer require to have a high-speed crypto-system, as it is used in high-traffic application to encrypt and decrypt data. Unfortunately, most of the end-node devices are resource-constraint and do not have enough area for security guard. Providing end-to-end security is vital for every network. To mitigate this issue, designing and implementing a lightweight cryto-system for resource-constraint devices is necessary.
In this thesis, a high-throughput FPGA implementation of AES algorithm for high-traffic edge applications is introduced. To achieve this goal, some part of the algorithm has been modified to balance the latency. Inner and outer pipelining techniques and loop-unrolling have been employed. The proposed high-speed implementation of AES achieves a throughput of 79.7Gbps, FPGA efficiency of 13.3 Mbps/slice, and frequency of 622.4MHz. Compared to the state-of-the-art work, the proposed design has improved data throughput by 8.02% and FPGA-Eff by 22.63%.
Moreover, a lightweight architecture of AES for resource-constraint devices is designed and implemented on FPGA and ASIC. Each module of the architecture is specified in which occupied less area; and some units are shared among different phases. To reduce the power consumption clock gating technique is applied. Application-specific integrated circuit (ASIC) implementation results show a respective improvement in the area over the previous similar works from 35% to 2.4%. Based on the results and NIST report, the proposed design is a suitable crypto-system for tiny devices and can be supplied by low-power devices.
Furthermore, two lightweight crypto-systems based on Binary Ring-LWE are presented for IoT end-node devices. For one of them, a novel column-based multiplication is introduced. To execute the column-based multiplication only one register is employed to store the intermediate results. The multiplication unit for the other Binary Ring-LWE design is optimized in which the multiplication is executed in less clock cycles. Moreover, to increase the security for end-node devices, the fault resiliency architecture has been designed and applied to the architecture of Binary Ring-LWE. Based on the implementation results and NIST report, the proposed Binary Ring-LWE designs is a suitable crypto-system form resource-constraint devices
Social Media Sentiment and Stock Return
Get PDFTechnology advancements increase people’s engagements in social media and make a great framework for analyzing investors’ behavior. Social media sentiment is the overall mood of investors shared on social media platforms and can affect readers’ investment decisions and the stock return. During the literature review, we found inconsistent empirical results for the relationship between social media sentiment and stock return. In addition, this relationship’s moderators must be theoretically and empirically analyzed. Using a panel regression over investors’ sentiment extracted from the two biggest financial and non-financial social media platforms (StockTwits and Twitter), we have checked if social media sentiment can predict S&P500 stock return and if the sentiment effect varies among different firm characteristics and market conditions. The findings suggest that positive (negative) sentiment has a significantly positive (negative) effect on stock return, while negative sentiment has a stronger effect. In addition, the sentiment effect is stronger among the firms that are smaller, high volatile, and has higher attention on social media platforms, specifically during bearish markets. Our findings indicate that social media sentiment is a risk factor separated from other previously studied risk factors
Tobacco in Stó:lō Historical Consciousness. Change and Continuity Through Intersectional Stigmas and Honours
No full textThe abstract of this item is unavailable due to an embargo
Genetic variation and genome-environment association of alfalfa (Medicago sativa L.) populations under long-term grazing
Get PDFAlfalfa (Medicago sativa. L) is the most valuable forage legume for the beef, dairy, and forage industries in Canada with approximately 4 million hectares of alfalfa and alfalfa-grass mixtures in Western Canada. Alfalfa forage production has been limited by low stand persistence due to the negative impacts of environmental factors and continuous grazing. The objectives of this study were: 1) to identify the phenotypic and genetic diversities of alfalfa populations collected from long-term grazing sites across four soil zones of Saskatchewan; 2) to compare genetic structure of the populations from long-term grazing sites to commercial alfalfa cultivars released between 1926 and 1980; 3) to identify the SNP markers linked to morphological traits and nutritive values; and 4) to detect SNP markers associated with environmental factors associated with plant persistence at long-term grazing sites. This study collected alfalfa populations across four soil zones of Saskatchewan representing 14 alfalfa stands with minimum 25 years of grazing history. The seven agro-morphological and three nutritive value traits of the 14 alfalfa populations from long-term grazing were evaluated in a replicated field trial using a nested randomized complete block design (RCBD). The genotyping-by-sequencing (GBS) reads were aligned to the Medicago sativa reference genome and 19,853 high-quality SNPs were generated. The STRUCTURE analysis identified that the alfalfa populations from long-term grazing sites were the hybrid cross from subspecies Medicago sativa subsp. sativa (hereafter M. sativa) and M. falcata. Plants from the Black soil zone produced the highest forage dry matter yield, plant height, and stem number, while the lowest values for these traits were recorded plants from the Brown soil zone. This was because the alfalfa populations from the Black soil zone had maintained more of the M. sativa genome over long-term grazing, while the alfalfa populations from the Brown soil zone maintained more of the M. falcata genome. The genotype-environment association (GEA) identified 70 SNPs for the alfalfa populations with grazing history including summer extreme temperature (22 SNPs), growing season precipitation (15 SNPs), soil nutrient (30 SNPs), and soil pH (3 SNPs). Fifty-three candidate genes were significantly associated with eight environmental factors, which were mainly involved in plant resistances to biotic and abiotic stresses, such as heat, drought, salt and diseases. The genome-wide-association-study (GWAS) analysis identified nine SNPs associated with stem number and nutritive value on the Medicago sativa reference genome. Once validated, these markers and candidate genes identified in the study would be useful for developing markers for marker-assisted selection to improve alfalfa cultivars with enhanced tolerance to long-term grazing and environmental stresses in Western Canada
The Disease of the Civilized: African Insanity and Colonial Psychiatry in Ghana, 1902-1957.
Get PDFThis thesis discusses the understudied and essential contributions of British psychiatrist and anthropologist Margaret Joyce Field to colonial psychiatry in Africa. In the 1930s, colonial psychiatrists believed Africans did not experience mental diseases or insanity before colonial contact. For John Colin Carothers, the most influential colonial psychiatrist, mental diseases only emerged in African communities as their cultures struggled to adapt to the abstract ideas introduced by European colonization. By drawing on the often-overlooked work of Field, and the Ghanaian concept of insanity, this thesis demonstrates how colonial psychiatrists disregarded mental diseases and their traditional therapies in rural Africa by dismissing them as cultural traits and superstition. This thesis shows how Ghanaians conceptualized insanity before British colonization. It uses the works of Field to highlight how Africans conceptualized insanity in Ghana before colonial contact. More importantly, the thesis emphasizes how the understanding of mental diseases or insanity was culturally constructed in a colonial context. It demonstrates how essential knowledge of African cosmology and cultural beliefs like witchcraft and juju are to understanding psychiatry on the continent. Despite Field’s insightful contribution to colonial psychiatry, this thesis indicates how she misinterpreted socio-cultural beliefs like witchcraft and its associated practices as signs of mental diseases in Ghana
X-ray absorption spectroscopy and X-ray diffraction data for molybdenum minerals and compounds
Get PDFCopyright © 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/)This work was supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) CREATE to INSPIRE program and the Canadian Light Source, which is supported by
the Canada Foundation for Innovation, the Natural Sciences and Engineering Research Council of Canada (NSERC), the University of Saskatchewan, the Government of Saskatchewan, Western Economic Diversification Canada, the National Research Council Canada, and the Canadian Institutes of Health Research. This work was also supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) through a Discovery Grant (Grant No. RGPIN-2020-05172) held by MBJL.Peer ReviewedWe report Mo K- and LIII-edge X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) data collected for 15 molybdenum minerals and compounds sourced from museum collections, mineral dealers, and chemical suppliers. The samples were finely ground and analyzed at the Canadian Light Source synchrotron (Saskatoon, Canada). The L III-edge XAS data were collected in fluorescence and total electron yield mode, while the K-edge XAS data were collected in transmission and fluorescence modes. Molybdenum L III-edge spectra cover the X-ray absorption near edge structure (XANES) region and Mo K-edge spectra cover the extended X-ray absorption fine structure (EXAFS) region. Tabulated XAS data are provided to support analysis of XAS data obtained for geological or environmental research. Furthermore, Mo K-edge EXAFS and L III-edge XANES spectra, the k3 weighted oscillatory χ(k) functions, and the Fourier-transforms in χ(R) of these K-edge data are presented graphically. Corresponding XRD data were collected as two-dimensional images against an area detector and integrated to form line scans. The data were collected at a wavelength of 0.68866 Å (18 keV) and is tabulated and presented graphically over a 0-40 °2Q range. This dataset is intended to be used as reference material for a variety of rare and common Mo phases
DEVELOPING A SYSTEMATIC APPROACH TO DESIGNING A DISCRETE EVENT CONTROL SYSTEM
Get PDFThe study reported in this thesis was aimed at laying a foundation for automating the design process of the discrete event control (DEC) system with the PLC (programmable logic controller) platform. The study had three objectives (in brief): (1) developing a model for technical specification of design requirements of DEC, (2) developing a systematic design process model for DEC, and (3) developing a framework for knowledge repository, in which the knowledge of systematic design of a DEC is stored.
The research activity was carried out to achieve the three objectives. First, the current model of the technical specification of design requirements for a functional product called General Design Process Model (GDPM) was revised to the model for a DEC. Second, the general design process model for functional products, such as the open-ended synthesis from a customer’s voice of needs of a DEC to a technical specification of the need, decomposition of functions along with the control functions (both feedback and feedforward), and open-ended synthesis of devices along with their DECs, was combined with the specific design process model for DEC, such as generation of state equation, and generation of the software ladder logic diagram (or generic PLC code). Third, the type of knowledge to support each design step was identified and classified, and the structure of the knowledge was outlined. Last, a case study of designing a DEC for medical ventilator was conducted along with the simulation of the design to validate the efficacy of the design process model and knowledge repository. The research activities lead to the general conclusion that the objectives of this study can be achieved, suggesting that a computer system be feasibly built to conduct design of a DEC in future.
The main contribution of the study lies in the field of design automation, including (1) the finding that the entire design process has two parts: open-ended part (first part) and close-ended part (second part), and (2) the demonstration of the feasibility of automating the design process for a DEC, which will have positive impact to designing a DEC more effectively and efficiently
Use of Dynamic Risk Instruments to Assess Sexual Violence Risk in a Community-Supervised Sample of Men with Sexual Offense Convictions
Get PDFThe present study examined the predictive validity and psychometric properties of several actuarial risk measures developed to estimate likelihood of sexual recidivism, and one protective factor measure developed to assess protective factors related to desistance from sexual offending. Each of Static-99R (Helmus et al., 2012), Violence Risk Scale - Sexual Offense Version (VRS-SO; Wong et al., 2003-2017), STABLE-2007 (Hanson et al., 2007), Sex Offender Treatment Intervention Progress Scale (SOTIPS; McGrath et al., 2012), and Structured Assessment of Protective Factors for Violence Risk- Sexual Offence version (SAPROF-SO; Willis et al., 2017-2020) was rated based on file information of 200 community-supervised men with sexual offense convictions who were court mandated to receive assessments (and often treatment) at an outpatient forensic clinic in Edmonton, Alberta. Recidivism information was available for 172 men; mean follow-up time was 8.6 years. Nine percent of the sample was charged or convicted of a new sexual offense, 18.5% for any new violent (including sexual) charge or conviction, and 33% for any new charge or conviction. Predictive validity for all tools was obtained with respect to sexual, violent (including sexual), and general recidivism. All measures significantly predicted sexual (AUC = .65- .72) recidivism and dynamic measures were sometimes incremental to static measures in the prediction of sexual recidivism, depending on the pairing of predictors. An exploration of the structural properties of the VRS-SO dynamic items revealed a three-factor solution isomorphic to previous research (Olver et al., 2007; Olver & Eher, 2019). Further discrimination and calibration findings will be discussed, including implications for assessment and treatment of men convicted of sexual offenses