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The influence of grapevine cultivar, clone, and rootstock on cold hardiness and dehydrin proteins
Get PDFGrapevine cold hardiness is a critical phenotype that is impacted by genetic and environmental factors. The extent of intra- and inter-cultivar differences within the Vitis vinifera L. specie are not well characterized. The dehydrins are a family of proteins that is upregulated by cold temperatures and have seldom been studied in overwintering grapevines. This thesis contains four research articles on these topics. First, cold hardiness of different cultivars was compared using the Vine Alert database containing data from ten winters from more than twenty vineyards. We report average and maximum mid-winter hardiness for Cabernet franc, Cabernet Sauvignon, Chardonnay, Merlot, Pinot noir, Riesling, Sauvignon blanc and Syrah, showing that cultivar and year have a larger impact than site within a viticultural region. Acclimation and deacclimation rates were weakly influenced by cultivar and site, but significantly influenced by the time of the year and the year itself. Cold hardiness was then studied for different clone and rootstock combinations of Riesling (clones 49 and 239 on Riparia gloire and SO4, and 239 on 3309) and Sauvignon Blanc (clones 242, 297, 376, 530) over three winters (2016 to 2019). We demonstrated that clone and clone x rootstock interaction can influence cold hardiness to a greater extent than rootstock alone. We then studied the presence and relative concentration of dehydrin proteins. We identified six new dehydrin bands (23 kDa, 26 kDa, 35 kDa, 41 kDa, 48 kDa, 90 kDa), showed that their concentration peaked either mid-winter or immediately before deacclimation, and demonstrated that they were all correlated to cold hardiness. For the final chapter, we demonstrated intra- and inter-cultivar differences in the hardiness-dehydrin correlations, particularly for the 23 kDa band which is negatively correlated to the % maximum hardiness in Riesling but not in Sauvignon blanc. Riesling cold hardiness was strongly correlated to temperature before sampling, but dehydrin accumulation was strongly correlated to the temperature before sampling in Sauvignon blanc, a key difference in cold-exposure response. This thesis contains findings that are actionable for the industry and relevant for the ongoing research efforts in the field of cold hardiness
Raising the Bar: Testing Prospective Relationships Between Multidimensional Trait Perfectionism and Undergraduate Academic Achievement
No full textProspective associations between trait perfectionism and academic achievement among undergraduate students were tested via a random intercept cross-lagged panel model. Undergraduate students (N = 316) who were enrolled in the core first- and second-year courses of a social sciences undergraduate program (Mage = 18.01 years, SD = 0.06; 74.86% female) completed surveys on multidimensional perfectionism and authorized the use of institution-verified grades for research. At the between-persons level and in line with previous research, self-oriented perfectionism (SOP) was positively linked with academic achievement whereas socially prescribed perfectionism (SPP) was negatively related with academic achievement. At the within-persons level, an increase in academic achievement at the end of students’ first year of university, compared to their own personal mean, predicted an increase in SPP at the midterm of their second year of university, demonstrating that academic achievement may encourage undergraduate students to “raise the bar” via amplifying their perfectionistic tendencies.This research was undertaken, in part, thanks to funding from the Canada Research Chairs Program awarded to Danielle S. Molnar (CRC-2020-00095)
Teaching Applied Behaviour Analysis to Caregivers of Individuals with Acquired Brain Injury
Get PDFAcquired brain injury is the leading cause of death and disability worldwide, often leading to cognitive, physical, emotional, social, and behavioural difficulties. Challenging behaviours, such as resistance, refusal, and aggression, can prevent successful community reintegration following an acquired brain injury. The behaviour analytic strategy differential reinforcement has been demonstrated to reduce challenging behaviours effectively; however, applied behaviour analysis remains under-utilized in brain injury rehabilitation. This project used a modified nonconcurrent multiple-probe across groups design to evaluate an online training program to provide instruction to frontline workers on implementing differential reinforcement. In two groups, participants were exposed to a probe requiring them to apply differential reinforcement in simulated client interactions, and the percent correct was measured. The intervention provided instruction (i.e., didactic) about behaviour analytic principles and how to implement differential reinforcement (i.e., practical exercises with feedback). Participants' scores significantly increased from baseline, indicating that the online training program facilitated learning of differential reinforcement and increased frontline workers’ ability to implement differential reinforcement during the online simulated exercises
A Comparison of Methods for Teaching Discrimination of Acceptance and Commitment Therapy/Training Processes in Samples of Verbal Behaviour
Get PDFAccurate identification of the six core processes of Acceptance and Commitment Therapy/ Training (ACT) is foundational for practitioners, yet no published research has compared methods for teaching this skill. This exploratory study compared the efficacy and efficiency of two methods (discrimination training, DT and self-paced, mastery-based training, SPMB) for training graduate students to identify ACT processes using speech samples. Two ACT processes were selected as training targets based on a logical analysis conducted with six behaviour analysts trained in ACT. Respondents rated fusion/defusion and lack of present moment awareness (PMA)/PMA to be of relatively equal discrimination difficulty. The training procedures were compared in an adapted alternating treatment design embedded within a delayed concurrent multiple baseline design across three students. In the DT condition modules, participants viewed training videos, completed exercises, whereas in the SPMB condition modules, participants read chapters of an ACT text in the SPMB condition modules. Following modules in either condition, participants completed skill assessments to assess their ability to discriminate the target ACT skills. Participants listened to samples of verbal behaviour then selected which ACT process they observed. Skill assessment results suggest that the most efficacious training method is SPMB. However, when false positives (identifying a sample of verbal behaviour as the target skill when it is the control skill) are included in scoring, DT is the more efficacious training method. Participants did not rate one training method more favorably than the other. Findings have the potential to inform future ACT research and ultimately increase the effectiveness of ACT interventions
Hidden Laplace-Runge-Lenz symmetry groups of transformation in Classical Mechanics and General Relativity
Get PDFFor central force motion, the complete dynamical symmetry transformation group is derived
from the known complete set of conserved integrals:
energy, angular momentum, Laplace-Runge-Lenz (LRL) vector,
all of which are local constants of motion,
and a temporal quantity related to the LRL vector,
which explicitly involves the time coordinate.
The method uses Noether's theorem in reverse to obtain
the infinitesimal symmetry generator associated to each conserved integral.
For energy and angular momentum, the generators consist of
a time-translation and rotations, which are well known.
These generators describe infinitesimal point symmetries,
which have a simple geometrical meaning given by symmetries of Newtonian space-time.
In contrast, the generators for the LRL vector and the related temporal quantity
are not infinitesimal point symmetries but instead describe
infinitesimal dynamical symmetries that are not connected to space-time.
Their physical meaning is discussed for the example of Kepler orbits.
The first main result is a derivation of the explicit form of the finite symmetry transformations generated from the LRL vector and the temporal quantity.
The derivation involves going to an extended space of variables
and using a gauge freedom in the form of infinitesimal symmetry generators
in this space.
For a suitable choice of gauge, the generators take a fairly simple form
which allows finding the finite transformations by an explicit integration of the corresponding flow equations in the extended space.
These finite transformations describe new hidden dynamical symmetry groups.
The second main result consists of applying a similar method to find
the complete symmetry transformation group of the timelike geodesic equations
in Schwarzschild spacetime.
The transformations include a counterpart of the dynamical symmetries
in central force motion arising from the locally conserved LRL vector and the related temporal quantity.
The corresponding dynamical symmetries of the timelike geodesic equations
have not appeared previously in the literature
Strategies for Enhancing Community Science: A Sustainability Science Narrative
Get PDFCollaboration is essential to addressing contemporary environmental challenges. Community
science offers a unique opportunity to unite academics, practitioners, and the public in fostering
environmental stewardship. Currently, environmental practitioners are seeking to maximize
community science outcomes. This research study synthesized existing literature on community
science to heighten awareness about initiatives and offer recommendation strategies towards
enhancing outcomes. Collaboration with the Excellence in Environmental Stewardship Initiative,
a partnership between Brock University and Niagara Parks Commission, helped inform the
research questions and areas of interest that guided this study in community science. These areas
included connections to nature, engagement, environmental education, environmental protection,
and organizational capacity, collectively called the dimensions of community science. A content
analysis revealed 16 strategies to enhance these dimensions. Connecting individuals to nature in
community science was lacking in discussion and should be explored in future research. Overall,
this study provides strong examples of strategies that may enhance community science
outcomes
Investigating the Relationship Between Self-Confidence and Burnout for Professionals Supporting Adults with Developmental and Intellectual Disabilities Engaging in Challenging Behaviour
Get PDFProfessionals supporting adults with developmental and intellectual disabilities who engage in challenging behaviour (CB) are at increased risk for burnout, which contributes to the workforce crisis in the developmental services sector. Research on factors influencing burnout for professionals in this field comprises a growing body of literature, but the relationship between self- confidence and burnout remains unclear. This convergent mixed methods study aimed to explore support professionals’ conceptualization of self-confidence and potential factors associated with it and quantify the relationship between self-confidence and burnout. An online survey containing the Maslach Burnout Inventory and a self-confidence instrument, along with other closed- and open-ended questions, was distributed to 156 types of direct support professionals and 46 leaders in developmental services across Ontario, Canada (N=202). A preliminary model of self- confidence was constructed that contains several person-related, social, knowledge, and situational components. Length of time in the field, level of support from others, and types of CB exposed to were acknowledged factors reported to influence self-confidence. Furthermore, increased self- confidence significantly predicted lower burnout scores characterized by decreased emotional exhaustion, R2 = .048, F(1, 146) = 7.29, p = .008, decreased depersonalization, R2 = .026, F(1, 146) = 3.92, p = .049, and increased personal accomplishment, R2 = .097, F(1, 146) = 15.68, p < .001. Results may increase understanding of burnout and reduce burnout risk, thus enhancing the quality of supports provided. Additionally, the model of self-confidence may inform pertinent staff training targets for organizations in this field
A Preclinical Evaluation of the Separate and Combined Effects of Context Fading and an Extinction Cue on Mitigating ABA Renewal
Get PDFABA renewal as one type of behavioural relapse occurs when a behaviour successfully reduced in one context re-emerges when a previously experienced context is reintroduced. Due to the undesirable effects of renewal, mitigation strategies have been investigated. “Context fading” is one strategy in which the similarity between an intervention context and the context in which an intervention will be transferred is progressively increased. “Extinction cue” is another strategy and refers to the transfer of stimuli associated with an intervention to the context in which the intervention will be transferred to. In this translational investigation, we assessed the separate and combined effects of both mitigation strategies. Forty university students were divided in four groups and completed a computer task. In Phase 1, clicking in a rectangle during a blue background produced points. In Phase 2, the background changed to yellow, clicking on the rectangle was extinguished and dragging a circle into a dotted circle was reinforced. In Phase 3, the contingencies of Phase 2 remained, however, the background colour reverted to blue (as in Phase 1). The “Control Group” did not receive any mitigation strategy. The “Group Context Fading” was exposed to a gradual change in the background color from yellow to blue during Phase 2. The “Group Extinction Cue” was exposed to a red triangle inside the rectangle during Phase 2, which was transferred to Phase 3. The “Group Combined” received both strategies. Results showed a high degree of renewal in Control group. In contrast, Group Extinction cue produced smaller magnitude renewal. Both Context Fading and Combined groups did not show evidence for renewal. Results are discussed in terms of methodological differences in each strategy and practical recommendations for renewal mitigation in applied settings
St. Catharines Standard Subject File Collection - RG 789
No full textIn 2022, the St. Catharines Standard and Niagara Falls Review newspapers, under the ownership of Metroland Media Group, donated their subject file archives to the Archives & Special Collections department of the Brock University Library. It is an extensive collection of clippings, photo prints and negatives, microfilm, files, notes and more, dating as far back as the 1910s, but predominantly covering the 1960s through the 1990s. These files were assembled by newspaper staff over the years as a reference for new stories.The subject file reference archives of the St. Standard Newspaper collection, including newspaper articles, documents and photographs taken from the newspaper and other sources
Effect of red rooibos tea supplementation on body composition and metabolism in ovariectomized Sprague-Dawley rats
Get PDFThrough menopause, increases in visceral adipose tissue (VAT), reductions in lean mass, and decreases in energy expenditure are observed. These changes have been linked to increases in inflammation and oxidative stress that occur alongside the decline in ovarian estrogen production. The objective of this study was to determine if red rooibos (RR), a polyphenol-rich tea, can ameliorate changes to body composition and metabolic outcomes in the ovariectomized (OVX) rat model. 56 female, 6-month-old, Sprague-Dawley rats were randomly assigned to 4 groups (n=14 per group): SHAM-WATER, SHAM-RR, OVX-WATER and OVX-RR. Prior to assigned surgeries, body composition was assessed via dual energy X-ray absorptiometry (DXA) (iNSiGHT, Osteosys) and metabolic measures were recorded via Promethion metabolic caging system. The intervention (2.6 g RR/kg body mass, prepared in distilled water) was provided ad libitum for 12 weeks. As expected, OVX rats accumulated a higher whole-body fat mass %, lower lean mass %, and a higher body mass when compared to SHAM rats (p<0.05). At endpoint, OVX rats had a higher ovarian adipose depot mass (p=0.012) and inguinal adipose depot mass (p<0.001), with a trend for reduced brown adipose depot mass (p=0.072). All measures were standardized to body mass, respectively. OVX rats consumed a greater amount of food over time compared to the SHAM rats (p<0.05). SHAM rats consumed a greater quantity of fluid, regardless of whether they received water or RR (p<0.05). RR intervention did not attenuate the changes to body composition or metabolic outcomes observed in the OVX group. Moreover, this study provided a robust overview of the many physiological and metabolic changes that occur 12-weeks post-OVX