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- Resource Type:
- Article
- Creator:
- Langerman, S., Morin, P., Dujmovic, V., Iacono, J., and Collette, S.
- Abstract:
- A data structure is presented for point location in connected planar subdivisions when the distribution of queries is known in advance. The data structure has an expected query time that is within a constant factor of optimal. More specifically, an algorithm is presented that preprocesses a connected planar subdivision, G, of size n and a query distribution, D, to produce a point location data structure for G. The expected number of point-line comparisons performed by this data structure, when the queries are distributed according to D, is H' + O(H^{1/2}+1) where H'=H'(G,D)$ is a lower bound on the expected number of point-line comparisons performed by any linear decision tree for point location in G under the query distribution D. The preprocessing algorithm runs in O(n log n) time and produces a data structure of size O(n). These results are obtained by creating a Steiner triangulation of G that has near-minimum entropy.
- Date Created:
- 2013-02-25
- Resource Type:
- Report
- Creator:
- Stricker, Ulla de and Jordan, Isla
- Abstract:
- Information management (IM) in the Canadian public sector is a complex area involving many professions such as librarians, archivists, records managers and information technology professionals. This exploratory study looks at the literature and experiential (qualitative) evidence from IM professionals in order to paint a picture of information management principles and practice in the Canadian federal government. Personal interviews were conducted with 20 librarians, information managers, records managers and other information professionals. Responses indicated that although the public sector has made tremendous strides in IM, there is often a gap between IM policy and practice as shown by inconsistencies and confusion in day to day operations compounded by the decimation of federal libraries (which are repositories of external as well as government information). The study also looks at roles of librarians and other IM professionals now and in the future. These professionals are well positioned to help close the gap between information policy and practice, moving forward toward more coordinated and integrated practices in information management as well as making information accessible and usable for their clients. Such functions aid the Canadian public sector in becoming a more effective knowledge organization.
- Date Created:
- 2013-04-02
- Resource Type:
- Report
- Creator:
- Renon, Flavia
- Abstract:
- The purpose of this working paper is to examine the role of Personal Learning Environments (PLEs) in higher education. This information will serve as a framework to inform a study of PLE use at Carleton University.
- Date Created:
- 2013-04-30
- Resource Type:
- Article
- Creator:
- Tudin, Susan and Ballamingie, Patricia
- Abstract:
- This paper offer practical advice on publishing graduate student research within the discipline of geography, addressing the following questions: why, when, where, what, how and with whom? Section 'The paper chase' delineates the importance of publishing, identifies potential material to publish, suggests venues in which to publish and offers pragmatic advice on how to negotiate the publishing process (with regards to peers, supervisors and editors). Section 'In library resources' discusses the effective use of library resources, demystifies the significance of impact factors and elucidates the history of Open Access publishing.
- Date Created:
- 2013-09-18
- Resource Type:
- Report
- Creator:
- McKenna, Julie and Jordan, Isla
- Abstract:
- Accountability and data-informed decision-making are increasingly important for Canadian public institutions such as governments and universities. Canadian university libraries also appear to be placing more emphasis on evaluating and assessing their services and products. To discover more about the current assessment culture in Canadian university libraries, in 2007 Isla Jordan from Carleton University and Julie McKenna from the University of Regina conducted an online survey of services assessment practices in Canadian university libraries. The goals of this project were to gain a sense of assessment practices within the libraries and to provide a baseline for future comparisons and research into services assessment practice. Results showed that survey respondents were at different stages in assessing a variety of services and products. Respondents indicated that their libraries intended to increase their assessment activities in the future, particularly the LibQUAL survey.
- Date Created:
- 2013-09-30
6. Vividness of visual imagery and incidental recall of verbal cues, when phenomenological availability
- Resource Type:
- Article
- Creator:
- Zakizadeh, Jila, Runge, Matthew, Faulkner, Andrew, D'Angiulli, Amedeo, Morcos, Selvana, and Chan, Aldrich
- Abstract:
- The relationship between vivid visual mental images and unexpected recall (incidental recall) was replicated, refined, and extended. In Experiment 1, participants were asked to generate mental images from imagery-evoking verbal cues (controlled on several verbal properties) and then, on a trial-by-trial basis, rate the vividness of their images; 30 min later, participants were surprised with a task requiring free recall of the cues. Higher vividness ratings predicted better incidental recall of the cues than individual differences (whose effect was modest). Distributional analysis of image latencies through ex-Gaussian modeling showed an inverse relation between vividness and latency. However, recall was unrelated to image latency. The follow-up Experiment 2 showed that the processes underlying trial-by-trial vividness ratings are unrelated to the Vividness of Visual Imagery Questionnaire (VVIQ), as further supported by a meta-analysis of a randomly selected sample of relevant literature. The present findings suggest that vividness may act as an index of availability of long-term sensory traces, playing a non-epiphenomenal role in facilitating the access of those memories.
- Date Created:
- 2013-01-02
- Resource Type:
- Article
- Creator:
- Fitzsimmons, Lauren P., Harrison, Sarah J., Thomson, Ian R., and Bertram, Susan
- Abstract:
- Phenotypic plasticity can be adaptive when phenotypes are closely matched to changes in the environment. In crickets, rhythmic fluctuations in the biotic and abiotic environment regularly result in diel rhythms in density of sexually active individuals. Given that density strongly influences the intensity of sexual selection, we asked whether crickets exhibit plasticity in signaling behavior that aligns with these rhythmic fluctuations in the socio-sexual environment. We quantified the acoustic mate signaling behavior of wild-caught males of two cricket species, Gryllus veletis and G. pennsylvanicus. Crickets exhibited phenotypically plastic mate signaling behavior, with most males signaling more often and more attractively during the times of day when mating activity is highest in the wild. Most male G. pennsylvanicus chirped more often and louder, with shorter interpulse durations, pulse periods, chirp durations, and interchirp durations, and at slightly higher carrier frequencies during the time of the day that mating activity is highest in the wild. Similarly, most male G. veletis chirped more often, with more pulses per chirp, longer interpulse durations, pulse periods, and chirp durations, shorter interchirp durations, and at lower carrier frequencies during the time of peak mating activity in the wild. Among-male variation in signaling plasticity was high, with some males signaling in an apparently maladaptive manner. Body size explained some of the among-male variation in G. pennsylvanicus plasticity but not G. veletis plasticity. Overall, our findings suggest that crickets exhibit phenotypically plastic mate attraction signals that closely match the fluctuating socio-sexual context they experience.
- Date Created:
- 2013-07-22
- Resource Type:
- Article
- Creator:
- Katti, Madhusudan and Bertram, Susan
- Abstract:
- Evolutionary biology and ecology have always been collaborative enterprises, benefitting enormously from active communication of ideas among traditional academic networks of peers. The Internet age, with its thriving online social networks, offers new tools that can help our current generation of biologists to collaborate, and communicate with the public, more effectively. Having a dynamic web presence, being part of an active blogging, Facebook, or Google+ community, and being a strategic tweeter can help your research, teaching, and service programs. Below we outline how to be a strategically savvy and active social media scientist, and discuss some of the pitfalls to avoid wasting time. We highlight some ecologists and evolutionary biologists who are active in social media to help you understand the many ways social media can help you in your academic life.
- Date Created:
- 2013-07-07
- Resource Type:
- Article
- Creator:
- Holahan, Matthew, Cahill, Shaina, and Tuplin, Erin
- Abstract:
- Seasonal fluctuations in food availability show a tight association with seasonal variations in body weight and food intake. Seasonal variations in food intake, energy storage and expenditure appear to be a widespread phenomenon suggesting they may have evolved in anticipation for changing environmental demands. These cycles appear to be driven by changes in external daylength acting on neuroendocrine pathways. A number of neuroendocrine pathways, two of which are the endocrine mechanisms underlying feeding and stress, appear to show seasonal changes in both their circulating levels and reactivity. As such, variation in the level or reactivity to these hormones may be crucial factors in the control of seasonal variations in food-seeking behaviours. The present review examines the relationship between feeding behavior and seasonal changes in circulating hormones. We hypothesize that seasonal changes in circulating levels of glucocorticoids and the feeding-related hormones ghrelin and leptin contribute to seasonal fluctuations in feeding-related behaviors. This review will focus on the seasonal circulating levels of these hormones as well as sensitivity to these hormones in the modulation of food-seeking behaviors.
- Date Created:
- 2013-07-23
- Resource Type:
- Article
- Creator:
- D'Angiulli, Amedeo, Aragón-Flores, Mariana, Mukherjee, Partha S., Cross, Janet V., Gómez-Garza, Gilberto, Zhu, Hongtu, Chao, Chih-kai, Mora-Tiscareño, Antonieta, Franco-Lira, Maricela, Engle, Randall, Jewells, Valerie, Solorio, Edelmira, Weili, Lin, Medina-Cortina, Humberto, Torres-Jardón, Ricardo, Calderón-Garcidueñas, Lilian, and Ferreira-Azevedo, Lara
- Abstract:
- Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA) children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children). We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1) and/or inflammatory mediators in MCMA children. Thirty gram of dark cocoa with 680 mg of total flavonols were given daily for 10.11 ± 3.4 days (range 9–24 days) to 18 children (10.55 years, SD = 1.45; 11F/7M). Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p = 0.0002). Fifteen children (83%) showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter (PM) and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer's and Parkinson's diseases.
- Date Created:
- 2013-08-02