IslandScholar
Not a member yet
16367 research outputs found
Sort by
The association between self-esteem and dimensions and classes of cross-platform social media use in a sample of emerging adults – Evidence from regression and latent class analyses
No full textThere is growing interest in the role of social media use in young people's mental health, and self-esteem has been hypothesised as a potential link in this association. However, existing studies have tended to use basic indicators of use in isolation and single-platform data, and further, have not controlled for other key variables. To address these limitations, emerging adults completed online questionnaires on social media engagement and self-esteem. In line with the interpersonal-connection-behaviours framework we explored online behaviours that putatively connect and disconnect users, e.g. meeting new people and engaging in social comparisons, respectively. Data were analysed using two methodologies, facilitating examination of the relationship between self-esteem and individual engagement indicators (regression analysis) as well as patterns of use (Latent Class Analysis). Overall levels of use and upward social comparisons independently predicted variance in self-esteem scores, even after controlling for demographic and socioeconomic covariates. Further, membership to meaningful, empirically-derived classes of social media users was predicted by self-esteem. These findings indicate that the association between social media use, social comparisons and self-esteem is robust, and extends to multi-platform data. We argue that such a move away from studies of single-platform data is critical if findings are to be generalised
Precision irrigation strategies for sustainable water budgeting of potato crop in Prince Edward Island
No full textClimate change induced uneven patterns of rainfall emphasize the use of supplemental irrigation in rainfed agriculture. The Penman–Monteith method was used to calculate supplemental irrigation for water budgeting of a potato crop in Prince Edward Island, Canada. Cumulative gaps between rainfall and crop evapotranspiration (ETc) during August and September of the study years were due to high crop coefficient factor, justifying the need for supplemental irrigation. Pressurized irrigation systems, including sprinklers, fertigation, and drip irrigation were installed, to evaluate the impact of scheduled supplemental irrigation in offsetting deficits in irrigation water requirements in comparison with conventional practice of rainfed cultivation (control). A two-way ANOVA examined the effect of irrigation methods and year on potato tuber yield, water productivity, tuber quality, and payout. Sprinkler and fertigation systems performed better than drip and control treatments. In terms of payout returns and potato tuber quality (percentage of marketable potatoes), the sprinkler treatment performed significantly better than the other treatments. However, for water productivity, fertigation treatment performed significantly better than control and sprinkler treatments during both years. The use of supplemental irrigation is recommended for profitable cultivation of potatoes in soil, agricultural, and environmental conditions resembling to those of Prince Edward Island.Natural Sciences and Engineering Research Council of Canad
Vaccination strategy is an important determinant in immunological outcome and survival in Arctic charr (Salvelinus alpinus) when challenged with atypical Aeromonas salmonicida
No full textEndoparasites in dogs and cats diagnosed at the Veterinary Teaching Hospital (VTH) of the University of Prince Edward Island between 2000 and 2017. A large-scale retrospective study
No full textUniversity of Bologn
Applications of artificial intelligence and deep learning for sustainable water management in Prince Edward Island
No full textPrecision agriculture evaluates and quantifies the input needs of crops for their optimum yield and sustainable production. Growth of potato plants is highly sensitive to drought conditions, which drastically reduce tuber yield if precision supplemental irrigation (SI) is not provided. The hypothesis of this study, that the rainfall in Prince Edward Island is not enough for sustainable potato production in the island, was tested under three specific objectives including i) to model evapotranspiration with artificial intelligence for precision water resource management, ii) to determine the effects of different irrigation systems
(sprinkler, drip, fertigation and control; rainfed) on potato tuber yield, quality, payout returns, and iii) to model the groundwater levels of Prince Edward Island using deep learning methods to ensure sustainability of water balance in Prince Edward Island.
This study used deep learning, artificial neural networks (ANNs) and the standard hydrology models to estimate components of water cycle for their use and impact on potato production in Prince Edward Island. Reference evapotranspiration was estimated with recurrent neural networks (RNNs) namely long short term memory (LSTM) and Bidirectional LSTM. Four representative meteorological sites (North Cape, Summerside, Harrington and Saint Peters) were selected across the island. Crop specific evapotranspiration (ETc) was calculated from reference evapotranspiration (ETO) using Penman Monteith equation, FAO-56 method, ANNs, and RNNs, and LSTMs. Based on subset regression analysis, the highest contributing climatic variables namely maximum air temperature and relative humidity were selected as input variables for RNNs’ training (2011-2015) and testing (2016-2017) runs. The results suggested that the LSTM and idirectional LSTM are suitable methods to accurately (R2 > 0.90) estimate ETO for all sites except for Harrington. No major differences were observed in the accuracy of LSTM and Bidirectional LSTM. The potential gap between ETO and rainfall were highlighted for
assessing agriculture sustainability in Prince Edward Island. Analyses of the data highlighted that the cumulative ETO surpassed the cumulative rainfall potentially affecting yield of major crops in the island. Therefore, agriculture sustainability requires viable options such as SI to replenish the crop water requirements as and when needed. Results suggested that July, August, and September are relatively drier months of the study years and SI may be required to meet the crop water requirements.
In order to evaluate impact of SI, pressurized irrigation systems including sprinkler, fertigation and drip irrigation were installed at small-scale to offset deficit in soil moisture as compared to conventional practice of rainfed conditions, i.e., no irrigation practice (control). Significant differences in potato yield were observed between control and irrigation methods used in this study. A two-way ANOVA was run to examine the effect of irrigation methods and year on potato tuber yield, water productivity, tuber quality, and payout. In term of payout returns the sprinkler treatment performed significantly better than control, drip, and fertigation in 2018. However, in terms of water productivity, the fertigation treatment performed significantly better than the control and sprinkler treatments during both growing seasons. The lower water productivity of sprinkler irrigation was due to higher water consumption in comparison with drip and fertigation systems.
Needs of SI for potato production in Prince Edward Island can be met from groundwater pumping. This necessitates the budgeting of water cycle components for efficient management of water resources. In areas where groundwater pumping is common for SI or for domestic use, the inventory control of groundwater resources could become more convenient with the use of deep learning, ANNs, and RNNs namely a multilayer perceptron (MLP) and LSTM. The analysis of two watersheds namely Baltic and Long creep showed that the deep learning methods used in this study are accurate to simulate groundwater levels. Input variables for this watershed-scale modelling investigation included stream level, streamflow, precipitation, relative humidity, mean temperature, heat degree days, dew point temperature, and ETo. Using a hit and trial approach and various hyperparameters, all ANNs were trained from scratch (2011–2015) and validated (2016–2017). The stream level was the major contributor to GWL fluctuation for the Baltic River and Long Creek watersheds (R2 = 0.508 and 0.491 respectively). The MLP performed better in validation for Baltic River and Long Creek watersheds (RMSE = 0.471 and 1.15,
respectively). The deep learning techniques introduced in this study to estimate GWL fluctuations are convenient and accurate as compared to collection of periodic dips based on the groundwater monitoring wells for groundwater inventory control and management
Strategies for culturally responsive assessment adopted by educators in Inuit Nunangat
No full textThe education systems of Inuit Nunangat (the four regions of the Canadian Arctic that are the traditional homes of Inuit) have undergone significant change and continue to experience transitions in terms of purpose, curriculum, administration, and control. A key part of this transition is ensuring that the assessment of student learning is culturally responsive. Hence, the purpose of this study was to explore Inuit educators’ culturally responsive assessment practices. Five case studies were conducted in four regions of Inuit Nunangat (Nunatsiavut, Nunavik, Nunavut, and Inuvialuit) which resulted in a sample of 180 participants. In-depth interviews and focus groups were held with teachers, students, administrators, and Elders. Data were synthesized and resulted in themes related to the challenges and achievements in developing assessment practices that were grounded in Inuit culture, values, and worldview. We conclude recommending that more support and attention are needed to focus on developing culturally responsive assessment tools and understanding the impact of such tools on student success and engagement
Investor Relations and Corporate Communications (IRSC) and cost of debt and equity capital
No full textIn this study, we examine whether firms’ engagement in Investor Relations and Stakeholder Communication (IRSC) activities reduce the cost of information asymmetry at the time of external financing. We also analyze the intermediary role of financing source (debt vs equity) and the existing level of firm transparency. Measures of IRSC initiatives are frequency of press releases, frequency of events (conferences and meetings, including industry gatherings as well as investment bank seminars), ratio of question and answer portion to the length of events, the average length of answer per question asked during events, and the frequency of slides used in event presentations. Sample includes 1,190 firms listed on S&P1500 index (small, medium, and large-cap firms on NYSE, AMEX, and NASDAQ stock exchanges) from 1999 to 2018. Multiple regression analyses (with robust standard errors) show that press frequency and the portion of question and answer in events have a significant and positive relationship with the cost of financing and event frequency and the average length of answers have a negative association with the cost of financing. Multivariate multiple regression analyses (seemingly unrelated regression models) are used to control for simultaneous effects of debt and equity issue and show that these findings are more pronounced for firms of lower transparency who are going to issue equity compared to firms of higher transparency who are going to issue debt
Development of a 3D bioprinting system using a Co-Flow of calcium chloride mist
No full textThis paper describes a novel 3D bioprinting printhead that enables the fabrication of alginate constructs with strong layer adhesion and excellent shape fidelity. The developed printhead attachment is incorporated onto a commercial 3D bioprinter and enables both the delivery and collection of CaCl2 mist droplets to crosslink the alginate filaments within the printhead. It is shown that delivering and collecting CaCl2 in mist form prevents excess liquid from pooling on the print stage, which can cause over-gelation and disruption of the printed structure. The mist-based system also offers a wide range of adjustment of the size of the printed filament. Additionally, structures printed using this method are shown to be compatible with living cells. Overall, this development enables excellent printability of 3D hydrogel scaffolds for in-vitro tissue generation and drug discovery
Application of next generation sequencing for detection of protozoan pathogens in shellfish
No full textFood and waterborne protozoan pathogens can cause serious disease in people. Three common species Cryptosporidium parvum, Giardia enterica and Toxoplasma gondii can contaminate diverse shellfish species, including commercial oysters. Current methods of protozoan detection in shellfish are not standardized, and few are able to simultaneously identify multiple species. Here, we present a novel metabarcoding assay targeting the 18S rRNA gene followed by next generation sequencing (NGS) for simultaneous detection of Cryptosporidium spp., Giardia spp. and T. gondii spiked into oyster samples. We further developed a bioinformatic pipeline to process and analyze 18S rRNA data for protozoa classification. The ability of the NGS assay to detect protozoa was later compared with conventional PCR. Results demonstrated that background amplification of oyster and other eukaryotic DNA competed with that of protozoa for obtained sequence reads. Sequences of target protozoans were obtained across all spiking levels; however, low numbers of target sequences in negative controls imply that a threshold for true positives must be defined for assay interpretation. While this study focused on three target parasites, the ability of this approach to detect numerous known and potentially unknown protozoan pathogens make it a promising screening tool for monitoring protozoan contamination in food and water.Natural Science and Engineering Research Council of CanadaUniversity of Guelp
When it's at: An examination of when cognitive change occurs during cognitive therapy for compulsive checking in obsessive-compulsive disorder
No full textBackground and objectives
The cognitive theory of compulsive checking in OCD proposes that checking behaviour is maintained by maladaptive beliefs, including those related to inflated responsibility and those related to reduced memory confidence. This study examined whether and when specific interventions (as part of a new cognitive therapy for compulsive checking) addressing these cognitive targets changed feelings of responsibility and memory confidence.
Methods
Participants were nine adults with a primary or secondary diagnosis of OCD who reported significant checking symptoms (at least one hour per day) on the Yale-Brown Obsessive-Compulsive Scale. A single-case multiple baseline design was used, after which participants received 12 sessions of cognitive therapy. From the start of the baseline period through to the 1 month post-treatment follow-up assessment session, participants completed daily monitoring of feelings of responsibility, memory confidence, and their time spent engaging in compulsive checking.
Results
Results revealed that feelings of responsibility significantly reduced and memory confidence significantly increased from baseline to immediately post-treatment, with very high effect sizes. Multilevel modelling revealed significant linear changes in feelings of responsibility (i.e., reductions over time) and memory confidence (i.e., increases over time) occurred following the sessions when these were addressed. Finally, we found that improvements in these over the course of the treatment significantly predicted reduced time spent checking.
Limitations
The small sample size limits our ability to generalize our results.
Conclusions
Results are discussed in terms of a focus on the timing of change in cognitive therapy