208 research outputs found
Contextual Considerations of Green Stormwater Infrastructure Siting
Green infrastructure increasingly is used to ameliorate water quality and quantity problems caused by runoff in cities. Studies show how the spatial distribution of these Green Stormwater Infrastructure (GSI) sites are unevenly distributed relative to socioeconomic and demographic groups. Often this is described as an indicator of perpetuated environment injustice, given the purported social and environmental benefits of GSI. To assess equity, researchers often examine either who gets what with respect to environmental âgoodsâ such as tree canopy and other green infrastructures, or investigate the procedures, decision making processes, and power structures pertaining to planning processes. This paper uses both spatial analyses to examine where GSI is located and who lives nearby in New Haven, CT, and illuminates the processes by which those locations were determined. An environmental injustice pattern was not observed: most GSI were located in low-income communities of color. However, the process that led to the siting had very little to do with who was living where. Instead, GSI siting decisions were determined by funding opportunities and their site selection criteria, flooding, combined sewer infrastructure, and avoiding infrastructure conflicts on a street segment. Future spatial analyses could consider the implicit or explicit baselines for equity in light of the processes and constraints that determine how and where GSI gets installed, and better incorporate the process of green infrastructure allocation in the chosen analytical metrics. By examining the process (ie the âhowâ) and the outcomes (ie the âwhat went whereâ) this study broadens the spatial analyses to include embedded knowledge from those who actually make the decisions that ultimately determine the location of GSI
EpicFlow: Edge-Preserving Interpolation of Correspondences for Optical Flow
We propose a novel approach for optical flow estimation , targeted at large
displacements with significant oc-clusions. It consists of two steps: i) dense
matching by edge-preserving interpolation from a sparse set of matches; ii)
variational energy minimization initialized with the dense matches. The
sparse-to-dense interpolation relies on an appropriate choice of the distance,
namely an edge-aware geodesic distance. This distance is tailored to handle
occlusions and motion boundaries -- two common and difficult issues for optical
flow computation. We also propose an approximation scheme for the geodesic
distance to allow fast computation without loss of performance. Subsequent to
the dense interpolation step, standard one-level variational energy
minimization is carried out on the dense matches to obtain the final flow
estimation. The proposed approach, called Edge-Preserving Interpolation of
Correspondences (EpicFlow) is fast and robust to large displacements. It
significantly outperforms the state of the art on MPI-Sintel and performs on
par on Kitti and Middlebury
Transitivity of visual sameness
The way in which vision represents objects as being the same despite movement and qualitative changes has been extensively investigated in contemporary psychology. However, the formal properties of the visual sameness relation are still unclear, for example, whether it is an identity-like, equivalence relation. The paper concerns one aspect of this problem: the transitivity of visual sameness. Results obtained by using different experimental paradigms are analysed, in particular studies using streaming/bouncing stimuli, multiple object tracking experiments and investigations concerning object-specific preview benefit, and it is argued that the transitive interpretation of visual sameness is the most plausible given the current stage of knowledge. What is more, it is claimed that the way in which visual sameness is represented suggests that in some cases it should be characterized as a âprimitive samenessâ, similarly as in philosophical theories postulating âthisnessâ
Which way do I go? Neural activation in response to feedback and spatial processing in a virtual T-maze
In 2 human event-related brain potential (ERP) experiments, we examined the feedback error-related negativity (fERN), an ERP component associated with reward processing by the midbrain dopamine system, and the N170, an ERP component thought to be generated by the medial temporal lobe (MTL), to investigate the contributions of these neural systems toward learning to find rewards in a "virtual T-maze" environment. We found that feedback indicating the absence versus presence of a reward differentially modulated fERN amplitude, but only when the outcome was not predicted by an earlier stimulus. By contrast, when a cue predicted the reward outcome, then the predictive cue (and not the feedback) differentially modulated fERN amplitude. We further found that the spatial location of the feedback stimuli elicited a large N170 at electrode sites sensitive to right MTL activation and that the latency of this component was sensitive to the spatial location of the reward, occurring slightly earlier for rewards following a right versus left turn in the maze. Taken together, these results confirm a fundamental prediction of a dopamine theory of the fERN and suggest that the dopamine and MTL systems may interact in navigational learning tasks
Investigating microstructural variation in the human hippocampus using non-negative matrix factorization
In this work we use non-negative matrix factorization to identify patterns of microstructural variance in the human hippocampus. We utilize high-resolution structural and diffusion magnetic resonance imaging data from the Human Connectome Project to query hippocampus microstructure on a multivariate, voxelwise basis. Application of non-negative matrix factorization identifies spatial components (clusters of voxels sharing similar covariance patterns), as well as subject weightings (individual variance across hippocampus microstructure). By assessing the stability of spatial components as well as the accuracy of factorization, we identified 4 distinct microstructural components. Furthermore, we quantified the benefit of using multiple microstructural metrics by demonstrating that using three microstructural metrics (T1-weighted/T2-weighted signal, mean diffusivity and fractional anisotropy) produced more stable spatial components than when assessing metrics individually. Finally, we related individual subject weightings to demographic and behavioural measures using a partial least squares analysis. Through this approach we identified interpretable relationships between hippocampus microstructure and demographic and behavioural measures. Taken together, our work suggests non-negative matrix factorization as a spatially specific analytical approach for neuroimaging studies and advocates for the use of multiple metrics for data-driven component analyses
Visual illusions: An interesting tool to investigate developmental dyslexia and autism spectrum disorder
A visual illusion refers to a percept that is different in some aspect from the physical stimulus. Illusions are a powerful non-invasive tool for understanding the neurobiology of vision, telling us, indirectly, how the brain processes visual stimuli. There are some neurodevelopmental disorders characterized by visual deficits. Surprisingly, just a few studies investigated illusory perception in clinical populations. Our aim is to review the literature supporting a possible role for visual illusions in helping us understand the visual deficits in developmental dyslexia and autism spectrum disorder. Future studies could develop new tools â based on visual illusions â to identify an early risk for neurodevelopmental disorders
Recommended from our members
Visual short-term memory through the lifespan: preserved benefits of context and metacognition
Visual short-term memory ability falls throughout the lifespan in healthy adults. Using a continuous report task, in a large, population-based sample, we first confirmed that this decline affects the quality and quantity of reported memories as well as knowledge of which item went where. Visual and sensorimotor precision also worsened with advancing age, but this did not account for the reduced memory performance.
We then considered two strategies that older individuals might be able to adopt, to offset these memory declines: the use of contextual encoding, and metacognitive monitoring of performance. Context and metacognitive awareness were both associated with significantly better performance, however these effects did not interact with age in our sample. This suggests that older adults retain their capacity to boost memory performance through attention to external context and monitoring of their performance. Strategies that focus on taking advantage of these preserved abilities may therefore help to maintain short-term memory performance with advancing age. The paper reports on analysis of the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) data
Talking About Tiny Houses
This piece is a snippet of an interview from a larger research project titled: âThe Social Practice of Living and Travelling in Small Mobile Living Structuresâ. Using a style popularised by Studs Terkel in his book âWorkingâ (1974), I have used the intervieweeâs own words but manipulated the order of the sections to make a cohesive narrative about living in a Tiny House. Erin and Chris talk about life in their tiny house under the framework of Social Practice Theory, informing the reader about the skills, materials and meanings that have contributed to their current living situation
- âŠ