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- Resource Type:
- Article
- Creator:
- Dorin, Bryce A. and Ye, Winnie N.
- Abstract:
- Mode-division multiplexing (MDM) is an emerging multiple-input multiple-output method, utilizing multimode waveguides to increase channel numbers. In the past, silicon-on-insulator (SOI) devices have been primarily focused on single-mode waveguides. We present the design and fabrication of a two-mode SOI ring resonator for MDM systems. By optimizing the device parameters, we have ensured that each mode is treated equally within the ring. Using adiabatic Bezier curves in the ring bends, our ring demonstrated a signal-to-crosstalk ratio above 18 dB for both modes at the through and drop ports. We conclude that the ring resonator has the potential for filtering and switching for MDM systems on SOI.
- Date Created:
- 2014-02-13
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- Resource Type:
- Article
- Creator:
- DeRosa, Maria C. and Foster, Amanda
- Abstract:
- Aptamers are short, single-stranded nucleic acids that fold into well-defined three dimensional (3D) structures that allow for binding to a target molecule with affinities and specificities that can rival or in some cases exceed those of antibodies. The compatibility of aptamers with nanostructures such as thin films, in combination with their affinity, selectivity, and conformational changes upon target interaction, could set the foundation for the development of novel smart materials. In this study, the development of a biocompatible aptamer-polyelectrolyte film system was investigated using a layer-by-layer approach. Using fluorescence microscopy, we demonstrated the ability of the sulforhodamine B aptamer to bind its cognate target while sequestered in a chitosan-hyaluronan film matrix. Studies using Ultraviolet-visible (UV-Vis) spectrophotometry also suggest that deposition conditions such as rinsing time and volume play a strong role in the internal film interactions and growth mechanisms of chitosan-hyaluronan films. The continued study and development of aptamer-functionalized thin films provides endless new opportunities for novel smart materials and has the potential to revolutionize the field of controlled release.
- Date Created:
- 2014-05-08
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- Resource Type:
- Article
- Creator:
- MacIsaac, D. Gregory
- Abstract:
- I examine the relation between sensation and discursive thought (dianoia) in Plato, Plotinus, and Proclus. In Theaetetus, a soul whose highest faculty was sensation would have no unified experience of the sensible world, lacking universal ideas to give order to the sensible flux. It is implied that such universals are grasped by the soul’s thinking. In Plotinus the soul is not passive when it senses the world, but as the logos of all things it thinks the world through its own forms.Proclus argues against the derivation of universal logoi from the senses, which alone can’t make the sensible world comprehensible. At most they give a record of the original sense-impression in its particularity. The soul’s own projected logoi give the sensible world stability. For Proclus, bare sensation does not depend on thought, but a unified experience of the sense-world depends on its paradigmatic logoi in our souls.
- Date Created:
- 2014-05-14
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- Resource Type:
- Article
- Creator:
- Grover, Trina, Riva, Pat, Andrews, Sue, Cross, Emma, and Oliver, Chris
- Abstract:
- This article describes the progress made toward implementing Resource Description and Access (RDA) in libraries across Canada, as of Fall 2013. Differences in the training experiences in the English-speaking cataloging communities and French-speaking cataloging communities are discussed. Preliminary results of a survey of implementation in English-Canadian libraries are included as well as a summary of the support provided for French-Canadian libraries. Data analysis includes an examination of the rate of adoption in Canada by region and by sector. Challenges in RDA training delivery in a Canadian context are identified, as well as opportunities for improvement and expansion of RDA training in the future.
- Date Created:
- 2014-01-10
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- Resource Type:
- Article
- Creator:
- Sharp, David, Jones, Wayne, and Newton Miller, Laura
- Abstract:
- Within the past decade, academic libraries have seen a shift in purchasing from mostly print to mostly electronic. Although Carleton University Library (Ottawa, Canada) has experienced this shift, it had continued until recently to work within the confines of an organizational structure based on a print purchasing model. This paper will describe in detail the restructuring of the Library's collections and technical services departments to better meet growing electronic demands. Changes included dedicating more staff from print resources to e-resources, changing a librarian position to focus specifically on collections assessment, and shifting budgets to manage growing e-resources more efficiently. The authors will explore accomplishments and hurdles that needed to be overcome, cite lessons learned in making organizational shifts, and make some cautious predictions about future changes.
- Date Created:
- 2014-07-03
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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