VIURRSpace
The Libraries of Royal Roads University and Vancouver Island University collaboratively offer VIURRSpace to digitally preserve and showcase selected scholarly and creative works of the universities, together with special collections that represent the unique character of the region.
Recent Submissions
Item Aqueous naphthenic acids and polycyclic aromatic hydrocarbons in a meso-scale spill tank affected by diluted bitumen analyzed directly by membrane introduction mass spectrometry(Elsevier, 2022-10-15)With the increasing use of unconventional, heavy crude oils there is growing interest in potential impacts of a diluted bitumen (DB) spill in marine and freshwater environments. DB has the potential to release several toxic, trace organic contaminants to the water column. Here, the aqueous concentrations and compositions of two classes of organic contaminants, naphthenic acids (NAs) and polycyclic aromatic hydrocarbons (PAHs), are followed over 8 weeks after a simulated spill of DB (10 L) into a freshwater mesocosm (1200 L) with river sediment (2.4 kg). These complex samples contain biogenic dissolved organic matter, inorganic ions, petroleum contaminants, suspended sediments, and oil droplets. We report the first use of condensed phase membrane introduction mass spectrometry (CP-MIMS) as a direct sampling platform in a complex multi-phase mesocosm spill tank study to measure trace aqueous phase contaminants with little to no sample preparation (dilution and/or pH adjustment). CP-MIMS provides complementary strengths to conventional analytical approaches (e.g., gas- or liquid chromatography mass spectrometry) by allowing the entire sample series to be screened quickly. Trace NAs are measured as carboxylates ([M-H]-) using electrospray ionization and PAHs are detected as radical cations (M+•) using liquid electron ionization coupled to a triple quadrupole mass spectrometer. The DB-affected mesocosm exhibits NA concentrations from 0.3 to 1.2 mg/L, which rise quickly over the first 2 – 5 days , then decrease slowly over the remainder of the study period. The NA profile (measured as the full scan in negative-electrospray ionization at nominal mass resolution) shifts to lower m/z with weathering, a process followed by principal component analysis of the normalized mass spectra. We couple CP-MIMS with high-resolution mass spectrometry to follow changes in molecular speciation over time, which reveals a concomitant shift from classical ‘O2’ naphthenic acids to more oxidized analogues. Concentrations of PAHs and alkylated analogues (C1 – C4) in the DB-affected water range from 0 to 5 μg/L. Changes in PAH concentrations depend on ring number and degree of alkylation, with small and/or lightly alkylated (C0 – C2) PAH concentrations rising to a maximum in the first 4 – 8 days (100 – 200 h) before slowly decaying over the remainder of the study period. Larger and heavily alkylated (C3 – C4) PAH concentrations generally rise slower, with some species remaining below the detection limit throughout the study period (e.g., C20H12 class including benzo[a]pyrene). In contrast, a control mesocosm (without oil) exhibited NA concentrations below 0.05 mg/L and PAHs were below detection limit. Capitalizing on the rapid analytical workflow of CP-MIMS, we also investigate the impacts of sample filtration at the time of sampling (on NA and PAH data) and sample storage time (on NA data only).Item Digital business transformation adoption in SMEs and large firms during COVID-19(Taylor & Francis, 2023-11-11)The COVID-19 pandemic has presented significant challenges for businesses worldwide. Those who recognised the importance of an online presence and transformed their traditional business model into a digital one were better equipped to mitigate the pandemic's negative impacts. However, there is a lack of research on the differences in digital transformation between small and medium-sized enterprises (SMEs) and large firms, as well as the main factors driving this transformation. This paper aims to address this gap by examining the successful digital transformation among these groups (SMEs and large firms) in the province of New Brunswick, Canada, as a case study. The study uses secondary data from the TechImpact survey to explore the primary factors of this shift for both SMEs and large firms. The study confirms the critical factors identified in the literature, while also revealing new factors specific to each group. For SMEs, these include adopting a digital business model, investing in low-budget social media and e-marketing, recruiting young digital experts, and accessing government grants and subsidies. For large firms, the factors include implementing mass customisation through online channels, providing remote work incentives, using a comprehensive content management system, and prioritising electronic customer relationship management and e-loyalty.Item Twisted-Internal Charge Transfer (TICT) state mechanisms may be less common than expected(Royal Society of Chemistry, 2024-02-02)We performed a combined experimental and ab initio study of the excited state dynamics of a carbazole–bromobenzothiadiazole (CBB) fluorophore, a molecule that was designed to exhibit strong solvatochromic shifts due to large charge separation in the minimum of the excited state potential energy surface. While the experimental Stokes shifts – obtained here through Excitation Emission Matrix spectroscopy – showed the expected large solvatochromic shift, we found no evidence that this shift is induced by a twisted-internal charge transfer (TICT) state as had been previously (and reasonably) predicted. Instead, ab initio calculations using TD-DFT and the CAM-B3LYP/6-31G+(d,p) (IEF-PCM) model explained the shift semi-quantitatively using a moderate charge separation in the excited state combined with small contributions of solvent-induced dipole moments in CBB that depend on the solvent polarity. While a TICT state could be identified as a local minimum on the S1 potential energy surface through its large dipole along the donor–acceptor axis and by examination of the natural transition orbitals, the global minimum on the S1 surface is close to the Franck–Condon region of excitation and much more accessible. This study highlights some of the complexities in identifying TICT states from experimental observations and frontier orbitals, alone.Item Integrating citizen science into the classroom to support inquiry-based learning(Science Council of the Alberta Teachers' Association, 2017-11)Public participation in scientific research is often referred to as citizen science. While the scientific benefits of citizen science are becoming more recognized, evidence of its educational value is also mounting. Citizen science has been shown to enhance engagement and interest in science, increase scientific literacy, develop science-related skills and contribute to lifelong science education.Item Paper spray mass spectrometry combined with machine learning as a rapid diagnostic for chronic kidney disease(Royal Society of Chemistry, 2024-03-19)A new analytical method for chronic kidney disease (CKD) detection utilizing paper spray mass spectrometry (PS-MS) combined with machine learning is presented. The analytical protocol is rapid and simple, based on metabolic profile alterations in urine. Anonymized raw urine samples were deposited (10 μL each) onto pointed PS-MS sample strips. Without waiting for the sample to dry, 75 μL of acetonitrile and high voltage were applied to the strips, using high resolution mass spectrometry measurement (15 s per sample) with polarity switching to detect a wide range of metabolites. Random forest machine learning was used to classify the resulting data. The diagnostic performance for the potential diagnosis of CKD was evaluated for accuracy, sensitivity, and specificity, achieving results >96% for the training data and >91% for validation and test data sets. Metabolites selected by the classification model as up- or down-regulated in healthy or CKD samples were tentatively identified and in agreement with previously reported literature. The potential utilization of this approach to discriminate albuminuria categories (normo, micro, and macroalbuminuria) was also demonstrated. This study indicates that PS-MS combined with machine learning has the potential to be used as a rapid and simple diagnostic tool for CKD.
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