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Guanahanolide A, a meroterpenoid with a sesterterpene skeleton from coral-derived streptomyces sp.
No full textA meroterpenoid, guanahanolide A (1), was purified from a fermentation extract of Streptomyces sp. RKBH-B7. The planar structure of guanahanolide A (1) was elucidated by NMR spectroscopy, revealing a meroterpenoid comprised of an unprecedented sesterterpene skeleton. Upon determination of the relative configuration of 1 through X-ray crystallography, its absolute configuration was unambiguously assigned using Mosher ester analysis. Guanahanolide A (1) showed moderate cytotoxicity against human cancer cell lines MCF-7, HTB-26, and HCT-116
Navigating uncharted waters: Considerations for training clinics in the rapid transition to telepsychology and telesupervision during COVID-19.
No full textThe COVID-19 pandemic offers both challenges and opportunities for those who provide and receive psychological services. For training clinics tasked with educating the next generation of health service psychologists, providing vital mental health care to the community, and conducting clinical research, the pandemic offers an opportunity to consider how best to fulfill these crucial missions during a time of global uncertainty. The present paper reviews the recent, rapid move to telepsychology among North American university training clinics in response to the COVID-19 pandemic and offers relevant suggestions for mental health service providers rapidly transitioning to telepsychology moving forward. Data summarizing the response of university training clinics in health service psychology in the United States and Canada to physical distancing guidelines are presented, and considerations regarding best practices in service delivery and supervision via telepsychology are provided. While the present data focus on North American training clinics, the suggestions offered are relevant to any clinic tasked with providing high quality services and training mental health providers via telepsychology, particularly during the COVID-19 pandemic. Given the growing emphasis within health service psychology on increasing access to mental health services via telepsychology prior to the pandemic, as well as the benefits to psychology trainees in gaining competence in this valuable form of service delivery, this paper aims to provide timely guidance around the benefits, risks, and practical considerations regarding the maintenance of effective clinical care in training settings when rapidly implementing telepsychology
Autonomous cell-based LiFePO4 battery management system for solar photovoltaic applications
No full textThis thesis documents the development of a novel lithium iron phosphate (LFP) battery management system (BMS) intended for solar photovoltaic power system applications. While lead-acid battery systems are often implemented without a BMS, lithium-based battery systems require a BMS to provide two critical functions: cell protection and balance. The proposed innovative BMS approach aims to enable lithium batteries to be installed in low-voltage autonomous building blocks and treated much like traditional lead-acid battery banks connected in series and parallel configurations. Particular attention is paid to realizing a lithium-based approach that implements a low-cost, highcurrent protection mechanism and emulates the natural energy-dissipating balancing behaviour of unmanaged lead-acid based cells. Initially, cell characterization results are presented for eight series connected 3.2 V LFP cells with a capacity of 3.7 Ah. Testing investigated imbalance up to 20% of cell capacity within the 24 V string and compared resultant reduced string capacity to charge time, required balance power, and charging effectiveness (time and capacity) under different external setpoints. Practical setpoint limitations for low voltage cut-off, constant current/constant voltage (CC/CV), and power specification for the dissipative element of the BMS are explored. Subsequently, a novel BMS architecture was proposed, simulated, built, verified, and tested. The BMS implements a noncommunicating and heat dissipating cell balance
architecture combined with a low-cost fuse-based cell protection mechanism. Both computer modelling and experimental testing of a 24 V nominal series string of LFP cells with a balance power curve emulating lead-acid battery self-balancing behavior to a maximum power of ~0.5 W per cell shows tolerance for greater than 50% single-cell imbalance (demonstrated to be the most difficult situation to manage on charge), charging at 1.85 A CC per cell, and 27.2 V CV (3.4 V per cell). On-demand cell protection using the cell’s own discharge capability to blow its own high-current fuse and disconnect the battery from the rest of the pack is demonstrated to be effective. However, this protection approach comes at the expense of some battery capacity (60 mAh per parallel cell) that is required to be available to blow the fuse in a low voltage disconnect condition. The novel BMS system concept is ultimately prototyped in the context of a full-scale 6 V nominal, 220 Ah (2S59P layout of 3.8 Ah/12.16 Wh 26650 LFP cells) battery in the GC- 2 form factor providing a functional initial prototype at a commercially viable scale
Missed opportunity in mathematics anxiety
No full textIn our technologically advanced society proficiency in mathematics is paramount to success in the science, technology, engineering, and mathematics (STEM) employment sector. Mathematics anxiety negatively affects an individual’s physiological and cognitive functioning, which results in the individual obtaining lower achievement in mathematics. The consequences of low mathematics achievement can have devastating consequences for the individual’s career in STEM fields which require high level mathematics. This article will provide a review of the prevalence of mathematics anxiety, its historical development, as well as theories from education, psychology, neuroscience and causal factors purporting to provide a comprehensive understanding of mathematics anxiety. We propose a fourth causal factor, missed opportunity, in which the individual is high functioning academically, but exhibiting mathematics anxiety. He or she is not able to perform well in mathematics due to missing the opportunity to learn the foundational mathematics knowledge necessary in STEM fields
Factorial sensitivity analysis of physical schemes and their interactions in RegCM
No full textIt is well known that the choices of physical schemes in Regional Climate Models (RCMs) can cause considerable uncertainties in future climate projections. In this study, a factorial sensitivity analysis method has been proposed to screen out statistically significant schemes and interactions, which assists in selecting the optimized physical scheme combination from a long‐term perspective with affordable computational costs. The Regional Climate Model (RegCM) is used as an example to illustrate how the approach works. In detail, all schemes are fully tested through 120 experimental runs based on a factorial design; the contributions and statistical significance (P value) of individual schemes and their interactions to temperature, precipitation, wind speed, and wind direction are then quantified. The performance of the proposed approach is then demonstrated through a case study of Canada. The results indicate that there exist considerable spatial and temporal simulated variations associated with different scheme combinations. It is also suggested that individual physical schemes have dominant influences on simulated variations, but some effects explained by their interactions are statistically significant and thus cannot be neglected. In particular, the planetary boundary layer (PBL) scheme, moisture scheme, and land surface model are found to be the dominant factors affecting the uncertainties of temperature, precipitation, and wind speed in future climate projections over Canada, respectively. Furthermore, the potential relationships between the vegetation cover conditions and the sensitivity of physical schemes are explored. The proposed approach is an attempt to analyze the sensitivity influenced by not only individual physical schemes and also their multilevel interactions.Natural Sciences and Engineering Research Council of CanadaWestern Economic Diversification CanadaNational Natural Science Foundation of ChinaNational Key Research and Development Program of Chin
Investigating the effectiveness of a causal MBSE software tool in modelling conceptual CubeSat data
No full textThe ongoing societal need for more complex electromechanical products has resulted in a parallel increase in challenges with managing product lifecycle data. Product Lifecycle Management and Systems Engineering are fields that were created to address these issues, but they are constantly needing to adapt to rapidly evolving engineering practices. To address these issues, this research explores the concept of using the SAPPhIRE Model of causality as a potential framework for structuring conceptual design product data. Previous literature had found the Model effective in representing the information of in-service and testing phases of the product lifecycle; however this work was limited to abstract textual descriptions of data with no consideration of the types and nature of the files. To expand on this literature, it was decided to tailor this research towards the conceptual design process, as it offered large cost impact on the product lifecycle, and would serve as a useful benchmark and reference for future work within the product development process. The objective of this research was to evaluate the effectiveness of the SAPPhIRE Model in supporting the conceptual design of CubeSat nanosatellites. The UPEI CubeSat design project offered access to a database that included all the product data, allowing for preliminary SAPPhIRE Models to be created and evaluated for their ability to both represent critical product data, and to maintain the rich depiction of causality. It was found that the models were able to effectively portray the product data without the need for extensive alteration of either SAPPhIRE, or the raw design files. A software tool, OPAL, was then created based on these models to allow for an empirical study to further investigate the utility of the SAPPhIRE Model. It allows users to view and access their design data using a GUI based on SAPPhIRE. To evaluate the research question, engineering students participated in a study where they would carry out typical conceptual design activities using OPAL and provide feedback regarding its effectiveness. The three major activities were the retrieval of design data, the use of subsystem domains and semantics, and the management of iterations. Results showed strong evidence of the effectiveness of OPAL; Students found that the consistent layout of SAPPhIRE for all of the subsystems in tandem with the GUI, streamlined the retrieval and tracking of design data. Qualitative feedback suggested modifying SAPPhIRE elements to aid understanding, and implementing functions such as a search feature. It was concluded that the SAPPhIRE Model has high potential for success in conceptual design, and should be further explored. Future work in this line of SAPPhIRE research should expand on the functionalities of OPAL, perform case studies concurrently with the design process, and explore the rest of the product development process
Different worlds same province: Blended learning design to promote transcultural understanding in teacher education
No full textThe history of Canada’s educational offerings for Indigenous students was based in colonial and assimilative practice. As such culturally responsive pre-service teacher education needs to respond not only by moving away from historical practice but with a moral and social imperative through programming that aids reconciliation. Current literature outlines the challenges that both Indigenous and mainstream teacher candidates have in developing efficacy towards transcultural skills development. In an effort to respond to both types of students, during the design and development of a 16-month community-based Bachelor of Education program, that was offered in parallel to a campus based program, a model of blended-education for cultural understanding was developed. Using the “elementary science methods” course as design case, this paper will outline the development of the blended model which paired campus- and community-based students. The challenges and successes of the design were determined through a thematic analysis of instructor observations of the pilot during the 2014-15 academic year. Four key themes emerged as important in fostering transcultural understandings within blended learning practice: student efficacy, relationship building, recognition of cultural bias, and legitimizing traditional ecological knowledge. Each of these will be discussed in the context of the course as well as transformative post-secondary educational experiences
