Metal-ligand cooperation in bis(phosphinimine)-supported rhodium pincer complexes: from dehydrogenation to value-added products

Expansion of methodology towards the synthesis of pincer ligand (L = κ3-NNN’ = 2,5-[iPr2P=N(4-iPrC6H4)]2-N’(C4H2)-) supported rhodium tetrylene (κ2-L(CO)Rh(ER2); E = Si, Ge; κ2-L = κ2-NN’-Rh, κ1-N-E) and borylene (κ2-L(CO)Rh(BMes); Mes = mesityl) species is described, followed by investigations into the reactivity of these new complexes. A metal-ligand cooperative approach was used to dehydrogenate group 14 starting materials of the form RR’EH2 (E = Si, Ge; R = aryl or alkyl; R’ = H, aryl or alkyl) and MesBH2 (Mes = mesityl), and the resulting complexes were characterized by a variety of instrumentational techniques (NMR, IR, EA). X-ray crystallography was used to unambiguously confirm the solid-state structure within these species, establishing the hemilability of the R3P=NAr “phosphinimine” nitrogen-donor of the pincer ligand as well as its base-stabilization capabilities. Diverse reaction chemistry was demonstrated for these species, starting with dehydrocoupling reactions with pinacol, which provided proof that the activated main group functionalities could be used as {BMes}, {SiRR’}, and {GeRR’} synthons and transferred to organic substrates. Additionally, reaction of a base-stabilized borylene complex with a variety of alkynes and CO gas yielded highly functionalized boron-containing heterocycles ((PhC=CRBMesO)C=NPipp) that would be difficult to synthesize by alternative routes, showcasing the potential these systems have for applications. Finally, the H-substituted silylene complex, κ2-L(CO)Rh(Si(H)Mes), was demonstrated to react with tris(pentafluorophenyl)borane to yield an elusive silylyne complex, the first of its kind with rhodium. Altogether, a cohesive body of work encompassing the development of new methodologies, diverse reaction chemistry, and the presentation of future areas for pursuit are described herein

Song type preferences during the dawn chorus in male Adelaide’s warblers (Setophaga adelaidae)

Songbirds sing a repertoire of song types, some of which are shared with neighbours. Songbirds prefer certain song types, but the reasons for these preferences are not well understood. I analyzed 11,800 dawn chorus songs from 14 male Adelaide's warblers (Setophaga adelaidae) to determine if males exhibit preference for specific song types and if these preferences are consistent across recording days. Each male had an average repertoire of 21.27 ± 3.62 song types. All males had song preferences, with the most preferred song type accounting for 17% of their song output. Song type preferences were consistent across days. I then omitted recordings that were not amenable to acoustic analysis, resulting in a reduced dataset (n = 9395), which I used to test whether males prefer (1) widely shared (locally prevalent) song types, (2) song types with superior transmission properties, or (3) song types with high or low vocal performance. I found strong evidence that males preferred widely shared songs, but the evidence for the second hypothesis was mixed. Males preferred song types with low frequency and low percent sound, supporting two predictions of the efficient sound transmission hypothesis. However, they did not prefer songs with high amplitude or high vocal deviation, negating the other two predictions of that hypothesis. Males preferred song types with low percent sound, as expected by the third hypothesis if they prefer songs with low performance requirement, but amplitude and vocal deviation had little effect on preference. This study supports the Social Dynamics Hypothesis, which states that social factors influence Adelaide's warblers' song type preference during the dawn chorus. Song sharing within the local communication networks influences male song preferences, although acoustic transmission properties and vocal performance may play a role as well

On the evolution of Pyrenophora tritici-repentis

Pyrenophora tritici-repentis (Ptr) is a globally distributed and economically important plant pathogen causing tan spot, a destructive foliar disease of wheat. The relatively recent emergence of Ptr provides a unique opportunity to better understand how necrotrophic pathogens evolve in modern agricultural systems. In this thesis, a variety of genomic and bioinformatic techniques were employed to examine the genomes of a large set of geographically diverse isolates with representatives from all of the established virulence races. These races contain different combinations of Ptrs three primary necrotrophic effectors: ToxA, ToxB, and ToxC. Comparison of total gene content between isolates found that Ptr possesses an open-pangenome, with a high accessory gene content (57%), and significant differences between pathogenic and non-pathogenic races. Putative effectors were found to be primarily accessory in nature, while carbohydrate-active enzymes associated with plant cell wall degradation were conserved. Gene distances and evolutionary rates suggest that the genomic architecture of Ptr is that of a ‘one-compartment’ genome despite having a high proportion of transposable elements (~18 to 25% of the genome). Significant chromosomal rearrangements were observed between isolates including the translocation of ToxA and the presence of ToxB within an accessory region. The translocation of ToxA, along with a 143 kbp region, was facilitated by the Starship transposon Horizon. Within Horizon, was nested the ToxhAT transposon which was responsible for the horizontal transfer of ToxA into Ptr. The accessory region which contains ToxB contained several Starship cargo genes but lacked other defining Starship characteristics, namely the requisite tyrosine recombinase. This region may be an accessory chromosomal arm, an ancient derelict Starship, or the beginning of genome compartmentalization. Detailed examination and extensive manual alignments between ToxB containing isolates revealed the presence of a Helitron-like transposable element, ToxB-HLE, which is replicating the ToxB gene in some isolates. Furthermore, two independent Copia retrotransposon insertions were found to be responsible for the disruption of ToxB thereby creating two of the known inactive toxb haplotypes. Finally, a genome wide association study revealed single-nucleotide polymorphisms significantly associated with the ToxC phenotype (-log(p) = 5.5). The nature of ToxC is unknown, and this analysis provides a number of candidate genes which may be involved in ToxC biosynthesis, secretion, or regulation. This body of work represents one of the most extensive examinations of the Ptr genome and its necrotrophic effectors preformed to-date and has shown that the pathogen exhibits high genome plasticity through not only through rearrangements but gene gains and losses as well. It also shows that transposons play a significant role in the evolution and adaptability of this global plant pathogen by mobilizing, replicating, and disrupting virulence genes

Montane seasonal and elevational precipitation gradients in the southern Rockies of Alberta, Canada

Open access article. Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International license (CC BY-NC-NC 4.0) appliesModelling precipitation inputs in mountainous terrain is challenging for water resource managers given sparse monitoring sites and complex physical hydroclimatic processes. Government of Alberta weather station uncorrected and bias-corrected precipitation datasets were used to examine elevational precipitation gradients (EPGs) and seasonality of EPGs for six South-Saskatchewan River headwater sites (alpine, sub-alpine, valley). January EPG from valley to alpine sites (730 m elevation difference) using uncorrected precipitation was 19 mm/100 m. Corrected EPG was approximately three times greater (61 mm/100 m). The valley received more precipitation than the alpine (inverse EPG) in late spring and summer. A seasonal signal was present whereby all sites demonstrated 50%–70% lower summertime precipitation relative to winter months, with the greatest seasonal variance at the alpine site. Winter watershed-level spatialized precipitation volume was compared to modelled snow water equivalent (SWE) associated with two late-winter airborne lidar surveys. Uncorrected volumes (2020: 64.0 × 106m3, 2021: 63.2 × 106m3) were slightly higher than modelled mean SWE (2020: 51.6 × 106m3, 2021: 44.2 × 106m3) whereas bias-corrected (2020: 120.5 × 106m3, 2021: 119.7 × 106m3) almost doubled the estimate. Corrected precipitation is assumed closer to the true value. Cumulative sublimation, evaporation and snowmelt losses result in ground-level snowpack yield that deviates from total atmospheric precipitation in an increasingly negative manner. The 2020/2021 simulations suggest wintertime atmospheric precipitation exceeds late-winter snowpack accumulation by up to 57% and 63%, respectively. A loss of 16 × 106m3 (7%) watershed SWE from the alpine zone was partially attributed to redistribution downslope to the treeline-ecotone. Physical snowpack losses from sublimation and melt, or modelling uncertainty due to precipitation correction and alpine snow-density uncertainties can also contribute to observed discrepancies between in situ SWE and cumulative precipitation. Ignoring bias-correction in headwater precipitation estimates can greatly impact headwater precipitation volume estimates and ignoring EPG seasonality is likely to result in under-estimated winter and over-estimated summer yields.Ye

No longer "us and them": integrating a recreation-based intervention as an interdisciplinary care approach in residential care settings

Recreation and leisure activities play a pivotal role in enhancing the holistic health for residents in residential care settings. Despite their proven benefits, these activities are often underutilized as an interdisciplinary care approach. The purpose of this study was to evaluate the effectiveness of the Feasible and Sustainable Culture Change Initiative (FASCCI) model on the integration of a recreation-based intervention (Tovertafel gaming console) as a routine interdisciplinary care approach in a residential care setting. Using an exploratory single-case, time series design, we assessed the impact of the FASCCI model training on outcomes across six-sequential time intervals (18-weeks total) by collecting baseline Tovertafel data (before the training) on two care floors and monitored its use post-training. Descriptive statistics and linear modeling were utilized to examine changes in Tovertafel use by interdisciplinary care team members from baseline across post-training intervals. Interviews (n = 7) and a feedback survey were also conducted to ascertain the participants’ perceptions of the process for implementing practice changes using the FASCCI model. Tovertafel use by interdisciplinary team members increased significantly according to a positive linear trend (F(1, 2) = 37.590. p<0.05, R2 = 0.949, r=0.974). Qualitative data indicated the application of the FASCCI model showed promise in breaking down interdisciplinary silos, and resulted in strengthened interdisciplinary relationships, holistic care provision, and shared decision-making. Quantitative and qualitative data demonstrated that it empowered nursing staff to view and utilize recreation as a means to assess resident needs and support daily care routines, leading to positive outcomes for the interdisciplinary team and residents

Exploring gender differences in the relationship between personal and environmental factors with the use of a campus fitness center

Open access. Creative Commons Attribution 4.0 International license (CC BY 4.0) appliesUniversity is a crucial period for developing lasting physical activity (PA) behaviors. The purpose of this study was to (a) explore differences in the strength and direction of the relationship between personal and environmental factors with one's use of a campus recreational facility (CRF) and the seven zones within it, and (b) test whether these relationships were influenced by gender. To test this, 648 university students provided responses to an online survey including CRF use, personal factors, and environmental factors. Eight path analyses were run with use of the CRF and the seven zones assigned as the eight dependent variables (one DV/analysis), gender as the moderator, and personal and environmental factors as the independent variables. An individuals’ task self-efficacy was the strongest factor (β = .16–.43; p < .05) related to use within each corresponding zone. Additionally, gender moderated several relationships between personal and environmental factors with use of the CRF and the distinct zones

Mechanisms of toxicity of the tire-wear compound N-(1,3-dimethylbutyl)-N’-phenyl-p-phenylenediamine-quinone (6PPD-quinone) in fathead minnows (Pimephales promelas)

N-(1,3-dimethylbutyl)-N’-phenyl-p-phenylenediamine-quinone (6PPD-quinone), is an emerging contaminant of concern (ECC) that has been recently identified as the primary cause of an acute lethality event observed in coho salmon (Oncorhynchus kisutch), termed Urban Runoff Mortality Syndrome (URMS). Given the widespread occurrence of 6PPD-quinone, there is a need to identify other species of fishes that experience acute lethality and sublethal toxicity following exposure, and to characterize mechanisms of toxicity. It is not known if fathead minnows (Pimephales promelas), a native species in North America, and a model species in ecotoxicology, are sensitive to 6PPD-quinone. Aqueous exposure to 6PPD-quinone did not cause mortality or embryo malformations in fathead minnows. Fathead minnow adults showed biochemical signatures of oxidative stress in both the livers and gills, including altered glutathione metabolism and an increase in methionine sulfoxide. This result suggested that fathead minnows could be used as a model species to investigate sublethal effects of 6PPD-quinone. However, fathead minnow embryos microinjected with 6PPD-quinone experienced a suit of cardiovascular abnormalities, including abnormal heart morphology, lack of common cardinal vein development, and hemorrhaging. Fathead minnow embryos that were microinjected with 6PPD-quinone showed a strong transcriptomic response, with alterations in pathways such as vascular endothelial growth factor signalling, endothelial cell-cell adhesion, and inflammation, providing a molecular basis for the cardiotoxicities. This supports the hypothesis that toxicokinetics is a critical determinant of 6PPD-quinone toxicity. This is the first study to demonstrate that sensitivity to 6PPD-quinone can be induced under laboratory conditions in insensitive species of fishes. Overall, this study fills critical knowledge gaps underlying mechanisms of toxicity of 6PPD-quinone to fishes

Twelve days in the career of a China missionary: Timothy Richard at the Protestant Conference in Shanghai in 1890

Open access article. Creative Commons Attribution 4.0 International license (CC BY 4.0) appliesThis article proposes to examine an obscure episode in the long career of the well-known Welsh Baptist missionary Timothy Richard, who went to China in 1870 and spent most of the next 45 years there. Richard attended the second general Protestant Missionary Conference in Shanghai in 1890 and served on committees, spoke at meetings, and presented a paper. The information available, though scanty, confirms key components of his approach to mission at this time: his goal was to achieve Chinese ‘salvation’ by promoting the principles and practices of what might be broadly termed ‘Christian civilisation’; his means of propagation was the written word; his preferred point of entry was contact with members of China's ‘ruling’ or ‘governing’ classes. In response to his call for action against anti-Christian, anti-Church propaganda, the conference appointed a permanent committee, with Richard as chair, to present an address on the ‘missionary question’ to the Qing government. It was this project that took him to Beijing in 1895, where he met with court officials and members of the educated elite, and established connections that involved him, rather haphazardly, in court politics in 1898. The sequence of events sheds light on an intriguing aspect of Sino–foreign relations during the late Qing period.Ye

Predictors of detoxification services use in Alberta: a provincial socio-demographic and utilization analysis

Detoxification is the first step in the substance use and addictive behaviours recovery process, serving as the transition between dependency and reduced use or abstinence. Completing detoxification is an important milestone in initiating recovery and remission of withdrawal symptoms, as well as facilitating follow-up treatment. However, high non-completion rates, low transition to residential treatment, and frequent use of detoxification services pose significant challenges to substance use disorder and behavioural addiction treatment and detox programs. This is the first study of the predictors in detoxification programs in Alberta, marking a significant step in understanding the predictors of completion and non-completion rates of detoxification, transfer to residential treatment, and repeated use of detox services based on data from five residential withdrawal management services in Alberta, Canada. The thesis consists of three manuscripts: (1) The first manuscript identifies the factors that predict detoxification service use, estimates program completion and non-completion rates, and the proportion of clients who cycle between completion and non-completion; (2) The second manuscript estimates clients' transition rates from detoxification to residential treatment services and identifies predictors of such transitions; (3) The third manuscript estimates the prevalence of repeated use of residential withdrawal management services in Alberta, Canada and identifies predictors of frequent use