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Investigating Vitis sp. cold stress tolerance with abscisic acid (ABA) analogs
Get PDFThe sustainability of Vitis sp. grapevine cultivation is threatened by climate change with pressure mounting on low temperature stress adaptations. Abscisic acid (ABA) is hypothesized to act as a central mediator of dormancy status and cold tolerance of grapevine buds. With one or more modifications to the chemical structure of ABA, synthetic analogs can improve its bioactivity in planta. The current research is founded in a comprehensive investigation on dormant grapevine bud cold stress responses following the administration of 8’-acetylene ABA (ABA-1017) and tetralone ABA (ABA-1016). Using V. vinifera (cv. Merlot) and interspecific Vitis hybrid (cv. Marquette) as freeze sensitive models, this thesis set out to determine: (1) the seasonal effect of ABA analogs on the resistance to losing cold tolerance; and (2) the impact of these products on bud dormancy physiology in relation to ABA catabolism. A record of five consecutive seasons (2017-2022) of differential thermal analysis data (DTA) was utilized to perform correlational test on the estimated low temperature exotherm (LTE) to the average minimum field temperature in deacclimation. Water content was measured for untreated, ABA-treated, and ABA analog-treated buds throughout the 2020-2021 and 2021-2022 dormant seasons. Samples were collected in alignment for hormone profiling (LC-MS/MS) to quantify the relative levels of ABA, its metabolites, and the degree of analog uptake/residual following application. Single-node cuttings from treated vines were maintained in a controlled environment (25°C, 16-hour light) to monitor the progression of dormancy against a fixed time-to-event threshold of 50% bud break over a 60-day observation window. Results suggest: (1) ABA analogs can improve deacclimation resistance and delay bud break, but their effect is inconsistent from year-to-year and varies in response to extreme cold stress; and (2) water availability and hormonal status are impacted by the application of ABA analogs unpredictably, and results from dormancy status evaluations are inconclusive to determine the impact of these products on the endo-ecodormancy transition of buds. This research ultimately lays the foundation to continue to explore the hallmarks of Vitis sp. bud dormancy and cold tolerance coordinated by ABA and develop an optimized freeze/frost-mitigation strategy for cool climate grape growers
On the Effectiveness of Video Prompting with Embedded Safety Checks to Teach Correct Child Passenger Safety Restraint Installation and Harnessing
Get PDFIn North America, motor vehicle collisions are the leading cause of unintended injury-related deaths among children under the age of 14. The primary cause of these deaths is the improper use of child passenger safety restraints (CPSR). Correctly installed CPSRs can decrease the risk of fatal injury by 45% to 95%. To date, no studies have used video prompting with embedded safety check to teach correct CPSR installation and harnessing in the absence of researcher implementation. We used a concurrent multiple baseline across participants design to evaluate the effectiveness of a video-prompting procedure with embedded safety checks to teach four prospective parents and caregivers CPSR installation and harnessing skills. All participants learned to perform these skills and these effects maintained for 4 weeks. Further, this training produced an improvement on all participants’ performance of an untrained installation position, vehicle, and harnessing skill, and these effects largely maintained for 4 weeks
Transition Metal-Free Hydrosilylation and Hydroboration of Unsaturated Carbon-Heteroatom Bonds
Get PDFThe hydrosilylation or hydroboration of unsaturated C-O and C-N bonds yields valuable reagents and intermediates for organic synthesis. Traditionally, these reactions have been carried out by transition metal catalysts which are generally expensive and toxic, or stoichiometric reagents which produce a significant amount of waste. As such, transition metal-free catalytic alternatives have steadily gained popularity as a more sustainable alternative. This thesis presents the use of cheap and readily available simple alkali metal bases such as KOtBu and nBuLi as powerful catalysts for the reduction of carbonyls and imines. Notably, aldehydes can be selectively obtained through the reduction of tertiary amides and esters, and amines can be produced from nitriles using a similar method. These conversions have previously been relegated to the domain of late transition metal catalysts. Variation of the silane or borane was found to be highly influential in adjusting the chemoselectivity. For example, in the conversion of amides to aldehydes, use of (EtO)3SiH resulted in overreduction to the amine product, whereas (EtO)2MeSiH allowed for selective reduction to the aldehyde equivalent. In this work, we discuss our investigations into the scope and selectivity of this straightforward yet effective system. Additionally, we introduce a new approach for achieving long-term precise control of reaction conditions at low temperatures
Settlement Workers Supporting Older Immigrant Women in a Smaller Urban Setting
Get PDFCanada relies on immigration to support economic, population and cultural growth. Immigrants face unique challenges related to settlement and integration into Canadian society. Settlement services can offer opportunities to mitigate challenges related to immigration for older immigrant women. However, there is a scarcity of literature exploring the experiences of settlement workers and the needs of older immigrant women in a small urban area. This study addressed gaps in the literature by answering the following question: How do settlement workers support older immigrant women in a smaller urban region setting? A constructivist lens coupled with a qualitative description approach was used. Six semi-structured interviews were conducted with settlement workers. Participants were asked about resources available to them, gaps in the services they provide, utilization of services, barriers to access, and needs of older immigrant women. Data was thematically analyzed. Four major themes emerged from the data: older immigrant women described from the perspective of settlement workers, potential barriers older immigrant women face in accessing services, the know-how of being a settlement worker, and the art of being a settlement worker. In the experiences of settlement workers, older immigrant women have more needs than other immigrant groups, such as younger and male immigrants; they also believe older immigrant women feel comfortable in seeking support from them. In the smaller urban setting, this support becomes crucial as there is usually less informal support available to them. The results of this study improved the understanding of the challenges encountered by settlement workers while working with older adult immigrant women in small urban region areas. Settlement workers identified the need for additional funding to support older immigrant women
How Virtual Tourism Environment Influences Purchase Intention? The Role of Mental Imagery and Affective Forecasting
Get PDFGiven the continuous advancement of information technologies in the presentation of online products, tourism practitioners have already increased the use of technology-mediated preview modes: web-based tours (2D) and virtual reality (VR). These digital technologies have influenced the way through which tourists search, book, plan, and experience travel (Beck & Egger, 2018). The existing body of tourism research has started to recognize the process of predicting future travel (Karl et al., 2021); however, far too little attention has been paid to affective forecasting in the tourism literature
Specifically, drawing on the PAD model, this research proposes a model that examines the effect of mental imagery (in VR vs. 2D) on purchase intention through and affective forecasting, and the moderating role of temporal distance on the association betwwen mental imagery and purchase intention through affective forecasting. An experimental study was conducted and the research model was tested using PROCESS macro with a sample of 526 participants. The finding demonstrated that VR surpasses 2D as a destination marketing tool due to its ability to break the temporal distance, resulting in greater predicted pleasure, predicted arousal and predicted dominance, and purchase intention. This study offers valuable insights for tourism and hotel managers who are considering the use of VR technology compared to 2D
"It's a very straight space": gender-diverse students' narratives about the library
Get PDFPresentation at the Atlantic Provinces Library Association Conference, June 2022How do students with diverse gender identities experience and perceive the academic library? What can we learn from our students to help develop services, spaces and collections that support their safety and well-being? This presentation will highlight results from a qualitative case study at an academic library by exploring themes related to the students’ experiences with library workers, the library’s physical environment and its collections. The study results position the library as both a source of positive, transformational potential and site of harm and oppression. Students reported experiencing great discomfort while using library bathrooms and study spaces and were distressed by encountering library materials containing outdated, inaccurate information about gender identity/sexual diversity. Gender diverse students described affirming experiences with library workers while being confronted with library technology – e.g. computers – which deadnamed them. And they questioned why libraries provide platforms to transphobic speakers in the name of intellectual freedom and highlighted the dangers of espousing neutrality. While themes surfaced by this study reflect the participants’ individual lived experiences, they are broadly reflected in survey results, scholarly literature and other research documenting these concerns. Finally, this presentation will describe students’ suggestions for how academic libraries can bridge the gaps to become safer and more inclusive. Attendees will be invited to reflect on changes they could incorporate in their home libraries
Stereoselective Synthesis of 1,1',2,2'-Tetrasubstituted Ferrocenes by Double Lithiation of a 1,1'-Disubstituted Ferrocenyl Pyrroloimidazolone
Get PDFThis thesis explores the synthesis of 1,1'-ferrocenyl pyrroloimidazolone for the double diastereoselective lithiation-electrophile quench to yield 1,1',2,2'-tetrasubstituted ferrocenyl compounds. The synthesis followed known literature procedures affording 1,1'-ferrocenyl bisacylazide that then underwent Curtius rearrangement followed by condensation with excess L-proline to yield the desired bishydantoin product. One-pot hydrozirconation/hydrosilylation reaction of the bishydantoin was performed affording the desired chiral pyrroloimidazolone auxiliary. Optimization of the lithiationsubstitution procedure with different amounts of t-BuLi followed by quenching with chlorotrimethylsilane (TMSCl) determined that 4 equivalents of base was necessary to yield predominantly 1,1',2,2'-tetrasubstituted ferrocenyl compounds. Other electrophiles were used to expand the scope of the reaction. The stereochemistry of the tetrasubstituted products was elucidated from X-ray crystallography of the stannane adduct, as well as transmetalation, elimination, and deuteration experiments. It was revealed that the tetrasubstituted products have R-planar (Rp) chirality and the reaction proceeded with high diastereoselectivity (>95:5 dr)
Boys–men mean-power-frequency differences in progressive exercise to exhaustion, confounded by variability and adiposity
Get PDFBackground: Only scant research has compared children’s mean power frequency (MPF) to adults’, with a clear overview still lacking. A significant obstacle has been MPF’s high variability, which this study aimed to overcome by elucidating the MPF characteristics distinguishing boys from men in progressive exhaustive exercise.
Methods: Electromyographic (EMG) data of 20 men (23.5 ± 2.5yrs) and 17 boys (10.2 ± 1.0 yrs), who performed progressively exhausting, intermittent isometric knee extensions, were subjected to secondary MPF analysis. Participants’ vastus lateralis MPF data series were transformed to third-order polynomial regressions and expressed as percentages of the peak polynomial MPF values (%MPFpeak). The resulting curves were compared at 5-% time-to-exhaustion (TTE) intervals, using repeated-measures ANOVA. Raw MPFpeak values were adiposity corrected to 0% fat and used to convert the %MPFpeak data back to absolute MPF values (Hz) for estimating muscle-level MPF.
Results: No overall interaction or group effects could be shown between the %MPFpeak plots, but pairwise comparisons revealed significantly higher men’s values at 50–70%TTE and lower at 100%TTE, i.e. boys’ shallower MPF rise and decline. The adiposity-corrected boys’ and men’s composite MPF values peaked at 125.7 ± 2.5 and 166.0 ± 2.4 Hz, respectively (110.7 ± 1.7 and 122.5 ± 2.1 Hz, uncorrected), with a significant group effect (p < 0.05) and pairwise differences at all %TTE points.
Conclusions: The boys were lower than the men in both the observed and, more so, in the adiposity-corrected MPF values that presumably estimate muscle-level MPF. The boys’ shallower MPF rise and decline conform to children’s claimed type-II motor-unit activation and/or compositional deficits and their related known advantage in muscular endurance
R&D, Innovation and The Business Cycle
No full textTechnological Innovation is a major driver of long-run economic development. It increases wealth
generation capacity, productivity, and rewards innovators with temporary monopoly profits. Part of the
innovation effort, investments in R&D are uncertain and long-run oriented, and absent market frictions,
should not be impacted by current economic conditions. This thesis investigates whether firms’ R&D
expenses respond to changes in short-run macroeconomic activity in the G7 countries, while considering
the endogenous relation between innovation and economic growth. Empirical studies attribute the procyclical behavior of R&D, especially in the U.S, to financial constraints that drive firms away from the
optimal allocation of resources. Moreover, substantial evidence indicates that managers manipulate
discretionary expenses to meet their current earnings targets, compromising other dimensions of the
business, such as future growth. We study whether macroeconomic conditions affect firm-level R&D
investments beyond what can be explained by financial factors and growth opportunities. Our results show
that contemporaneous macroeconomic conditions, as well as access to financing, are positively associated
with firm-level R&D intensity, most notably in young and high-tech firms. We find a positive association
with the 1-year lagged economic conditions in the U.S and Canada, but not in the other countries of the
G7. Recessions are especially significant in explaining cuts in R&D investments in all countries. Therefore,
R&D seems to be pro-cyclical regardless of financial constraints, suggesting that the latter relation with
earnings management activity might be complimentary, rather than mutually exclusive. We address the
endogenous nature of innovation and economic growth by estimating R&D and GDP in a panel Vector Auto
Regression (PVAR) and find no evidence that reverse causality impacts our results. Furthermore, although
aggregate level and the weighted average change in R&D of our sample are reasonably correlated, we do
not find a relevant long-run relation between firm-level R&D intensity and economic activity, which calls
for further investigation
Examining the combined effects of Cyberbullying, ethical climate, and dark triad personality on work outcomes: Unravelling the mechanisms of vengeful rumination and knowledge sabotage behaviours
Get PDFThe present study aims to examine the relationship between cyberbullying and knowledge sabotage, an extreme form of counterproductive knowledge sharing behaviour. The study considers vengeful rumination as a bridging mechanism between cyberbullying and knowledge sabotage, whereby victims of cyberbullying engage in retaliatory behaviour in response to a perceived interpersonal transgression. Although workplace bullying has been proposed as a potential antecedent of knowledge sabotage, there is no extant research on the link between cyberbullying and knowledge sabotage in the workplace. The prevalence of knowledge sabotage is alarming, with almost half of employees reporting being victims of sabotaged knowledge. Effective knowledge management is critical for organizational competitiveness, and information sharing barriers can cost firms millions of dollars annually. However, the mechanisms and causes of knowledge sabotage are not well understood.
This study aims to add to the existing research by looking at how cyberbullying, vengeful rumination, and knowledge sabotage are connected and their consequences. Particularly on an individual (psychological strain) and group level (interpersonal harmony and team performance). Furthermore, the study will examine the role of dark triad personality traits and a caring ethical climate in mitigating or exacerbating these relationships. The study will be the first to investigate how cyberbullying victimization impacts knowledge sabotage through vengeful rumination. The study's findings will have practical implications for organizations, allowing them to recognize the negative impact of cyberbullying on their employees and take measures to prevent it