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- Resource Type:
- Poster
- Creator:
- Tudin, Susan
- Abstract:
- Poster presented at the Teaching & Learning Symposium, Carleton University, May 11, 2016
- Date Created:
- 2016-05-11
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- Resource Type:
- Article
- Creator:
- Panchen, Zoe A. and Gorelick, Root
- Abstract:
- In temperate regions, there are clear indications that spring flowering plants are flowering earlier due to rising temperatures of contemporary climate change. Temperatures in temperate regions are rising predominantly in spring. However, Arctic regions are seeing unprecedented temperature increases, predominantly towards the end of the growing season. We might, therefore, expect to see earlier flowering of later-season flowering Arctic plants. Parks Canada has been monitoring purple saxifrage (Saxifraga oppositifolia) and mountain avens (Dryas integrifolia) flowering and fruiting times for 20 years at Tanquary Fiord, Qut- tinirpaaq National Park, Ellesmere Island. Saxifraga oppositifolia flowers in early spring, while D. integrifolia flowers in midsummer. Over the 20-year period, Tanquary Fiord’s annual and late-summer temperatures have risen significantly. During the same timeframe, D. integrifolia showed a trend towards earlier flowering and fruiting, but S. oppositifolia showed no changes in flowering or fruiting time. Flowering time was related to monthly temperatures just prior to flowering. The number of flowers produced was related to the previous autumn’s monthly temperatures. We found no relationship between flowering time and snowmelt date. Our findings suggest that Arctic community level ecological effects from climate change induced phenology changes will differ from those in temperate regions.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Millard, Koreen and Richardson, Murray
- Abstract:
- Random Forest (RF) is a widely used algorithm for classification of remotely sensed data. Through a case study in peatland classification using LiDAR derivatives, we present an analysis of the effects of input data characteristics on RF classifications (including RF out-of-bag error, independent classification accuracy and class proportion error). Training data selection and specific input variables (i.e., image channels) have a large impact on the overall accuracy of the image classification. High-dimension datasets should be reduced so that only uncorrelated important variables are used in classifications. Despite the fact that RF is an ensemble approach, independent error assessments should be used to evaluate RF results, and iterative classifications are recommended to assess the stability of predicted classes. Results are also shown to be highly sensitive to the size of the training data set. In addition to being as large as possible, the training data sets used in RF classification should also be (a) randomly distributed or created in a manner that allows for the class proportions of the training data to be representative of actual class proportions in the landscape; and (b) should have minimal spatial autocorrelation to improve classification results and to mitigate inflated estimates of RF out-of-bag classification accuracy.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Fitzgerald, Saira
- Abstract:
- This article presents the results of the first phase of a research project on perceptions of the International Baccalaureate Diploma Program (IBDP) in Canadian universities. Establishing explicit university recognition policies for IBDP students has been an ongoing task for the International Baccalaureate Organization (IBO), which conducted two studies on university perceptions of the IBDP in the UK (2003) and Australia/New Zealand (2007). The present study replicates these studies in the Canadian context, to discover how admissions officers in Ontario universities perceive the IBDP in relation to other curricula. Preliminary results reveal a high degree of uniformity in responses, consistent with the previous studies. The IBO is indicated as being the primary source of information, suggesting that it plays an important part in forming perceptions of the IBDP.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Smith, Catherine A., Hayley, Shawn, Smith, Jeffrey, and Farmer, Kyle
- Abstract:
- Parkinson’s disease (PD) is a progressive neurodegenerative disease affecting the nigrostriatal pathway, where patients do not manifest motor symptoms until >50% of neurons are lost. Thus, it is of great importance to determine early neuronal changes that may contribute to disease progression. Recent attention has focused on lipids and their role in pro- and anti-apoptotic processes. However, information regarding the lipid alterations in animal models of PD is lacking. In this study, we utilized high performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) and novel HPLC solvent methodology to profile phosphatidylcholines and sphingolipids within the substantia nigra. The ipsilateral substantia nigra pars compacta was collected from rats 21 days after an infusion of 6-hydroxydopamine (6-OHDA), or vehicle into the anterior dorsal striatum. We identified 115 lipid species from their mass/charge ratio using the LMAPS Lipid MS Predict Database. Of these, 19 lipid species (from phosphatidylcholine and lysophosphotidylcholine lipid classes) were significantly altered by 6-OHDA, with most being down-regulated. The two lipid species that were up-regulated were LPC (16:0) and LPC (18:1), which are important for neuroinflammatory signalling. These findings provide a first step in the characterization of lipid changes in early stages of PD-like pathology and could provide novel targets for early interventions in PD.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Capaldi, Colin A., Dopko, Raelyne L., and Zelenski, John M.
- Abstract:
- Research suggests that contact with nature can be beneficial, for example leading to improvements in mood, cognition, and health. A distinct but related idea is the personality construct of subjective nature connectedness, a stable individual difference in cognitive, affective, and experiential connection with the natural environment. Subjective nature connectedness is a strong predictor of pro-environmental attitudes and behaviors that may also be positively associated with subjective well-being. This meta-analysis was conducted to examine the relationship between nature connectedness and happiness. Based on 30 samples (n = 8523), a fixed-effect meta-analysis found a small but significant effect size (r = 0.19). Those who are more connected to nature tended to experience more positive affect, vitality, and life satisfaction compared to those less connected to nature. Publication status, year, average age, and percentage of females in the sample were not significant moderators. Vitality had the strongest relationship with nature connectedness (r = 0.24), followed by positive affect (r = 0.22) and life satisfaction (r = 0.17). In terms of specific nature connectedness measures, associations were the strongest between happiness and inclusion of nature in self (r = 0.27), compared to nature relatedness (r = 0.18) and connectedness to nature (r = 0.18). This research highlights the importance of considering personality when examining the psychological benefits of nature. The results suggest that closer human-nature relationships do not have to come at the expense of happiness. Rather, this meta-analysis shows that being connected to nature and feeling happy are, in fact, connected.
- Date Created:
- 2016-05-17
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- Resource Type:
- Thesis
- Creator:
- Hundlani, Kalpana
- Abstract:
- Many studies reflect that today's younger generation spends a considerable amount of time online whether for doing their homework or playing games. However, the authentication schemes for this user group has received negligible attention. When exploring alternate authentication mechanisms for children, we decided to reduce the password burden and involve parents in the authentication decision. We chose to explore whether a parent-child password manager was a good choice for achieving this goal. We started with our 'Keep A Secret' prototype, a parent-managed password manager for children. On the next iteration, we designed 'KinderSurf', a parental consent mechanism based on the OpenID concept. We conducted two user studies for evaluating the prototypes. These user studies revealed areas for improvements, but overall both parents and children like the idea of using parental consent to log in.
- Thesis Degree:
- Master of Computer Science (M.C.S.)
- Thesis Degree Discipline:
- Computer Science
- Date Created:
- 2016
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- Resource Type:
- Thesis
- Creator:
- Bingham, Michael John Kendal
- Abstract:
- Mobile devices store immense amounts of sensitive data, making them attractive targets for attackers. The first line of defence against attacks is authentication --- verifying the identity of an agent accessing the device. We examine behavioural biometrics as an effective authentication mechanism on mobile devices. Behavioural biometrics model an agent's behaviours to establish their identity. We construct an authentication system based on profiling the device sensors (touch screen, accelerometer and gyroscope) during a swipe, defined as a quick, simple movement across a touch screen. In addition, we explore the relationship between problem setting and evaluation methodology in authentication systems, producing a list of requirements necessary for accurate evaluation. Finally, we perform a user study to ascertain the effectiveness of our behavioural biometric mechanism. We conclude that this system is resistant to attacks which trivially bypass standard mechanisms such as PINs, while also potentially lightening the usability load imposed by authentication.
- Thesis Degree:
- Master of Computer Science (M.C.S.)
- Thesis Degree Discipline:
- Computer Science
- Date Created:
- 2016
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- Resource Type:
- Thesis
- Creator:
- McConnell, Erin Marie
- Abstract:
- Derived by an iterative in vitro selection process termed Systematic Evolution of Ligands by EXponential enrichment (SELEX), aptamers are short single-stranded oligonucleotides that bind to their cognate targets with high affinity and selectivity. Generally, aptamers have been widely used in biological and pre-clinical medical applications. A comprehensive analysis of aptamer selection data maintained in the Aptamer Database identified factors that should be carefully considered upon the design of selection experiments to optimize success. These findings should be applied to selections for nervous system related targets to improve the quality of selected aptamers. Specifically, the nervous system presents an especially interesting field of investigation. For example the aptamer target thrombin is a protein involved in the coagulation cascade and has important relevancy for stroke. The development of an aptamer-based pH-driven DNA nanomachine (pHAST) for the specific catch-and-release of thrombin is described. This work is an important example of how existing aptamers could be incorporated into a nanodevice to add specific functionality for applications within the nervous system. Dopamine is a small molecule neurotransmitter implicated in mental illness and neurodegenerative disease. The ability of dopamine-binding aptamers to attenuate perseveration and locomotor behaviour associated with dopamine over-activity was shown in live rodents. Finally, an aptamer-gold nanoparticle based sensor was developed based on a dopamine binding aptamer, DopaA20min, identified from a novel selection.
- Thesis Degree:
- Doctor of Philosophy (Ph.D.)
- Thesis Degree Discipline:
- Chemistry
- Date Created:
- 2016
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- Resource Type:
- Thesis
- Creator:
- Strickland, Noelle
- Abstract:
- Socially anxious students may be at risk for heavy drinking and alcohol-related problems (e.g., injuries), because they may endorse more maladaptive drinking motives, such as drinking to cope with their anxiety or to conform to peer-pressure (Hingson et al., 2005). This study assessed two conceptual models: 1) whether social anxiety predicts drinking motives, which in turn predict alcohol-outcomes (i.e., a mediation model), and 2) whether social anxiety exacerbates the effect of drinking motives on alcohol-outcomes (i.e., moderation model). Undergraduates (N = 387) completed an online survey, and of these n = 76 completed a follow-up brief survey study. Both surveys assessed social anxiety, drinking motives, and alcohol-outcomes. Results showed that coping and conformity motives explained the associations between social anxiety and alcohol-related problems, and coping motives explained the association between social anxiety and heavy drinking.Keywords:social anxiety; drinking motives; heavy drinking; alcohol-related problems; brief surveys; university students.
- Thesis Degree:
- Master of Arts (M.A.)
- Thesis Degree Discipline:
- Psychology
- Date Created:
- 2016