Measuring the Exposure and Vulnerability of Transit Riders to Cold Temperatures in London, Ontario

Due to the expansion of suburban areas in many cities around the world, accessibility to public transit through walking has become a new challenge for riders. Considering the impacts of climate change in creating more extreme weather, such as extreme cold, heat, or flooding, transit riders may thus be at a higher risk of exposure for various weather-related illnesses (Fraser & Chester, 2016). Using ArcGIS Pro and ArcMap software, and data collected from City of London’s Open Portal, the United States Geological Survey, Open Mobility Data, and Statistics Canada, the exposure and vulnerability of transit riders to cold temperatures in London were calculated and visualized. This was done by measuring the walking distance from the center of postal codes to the three closest bus stops, and thereafter calculating the average land surface temperature along the respective route. The analysis excluded areas where the average distance to the closest stop was beyond 800 meters, since it be would unlikely for an individual to walk longer distances to access public transit (Fraser & Chester, 2016). The information was then amalgamated and averaged to the dissemination area scale in order to standardize the neighbourhoods to match census tracts. The cold exposure index was then calculated by multiplying the average walking time to the closest bus stop with the average absolute value of the land surface temperature of the respective route. A walking speed of 4.7 km/h, consistent with the average human walking speeds, was selected for the analysis. Lastly, the median total income and visible minority population data within private households in each neighborhood in London were collected and visualized using the 2016 national census to discern any equity implications related to the vulnerability of riders

Formalization of the fundamental group in untyped set theory using auto2

We present a new framework for formalizing mathematics in untyped set theory using auto2. Using this framework, we formalize in Isabelle/FOL the entire chain of development from the axioms of set theory to the definition of the fundamental group for an arbitrary topological space. The auto2 prover is used as the sole automation tool, and enables succinct proof scripts throughout the project.Comment: 17 pages, accepted for ITP 201

Customized Versus Noncustomized Sound Therapy for Treatment of Tinnitus: A Randomized Crossover Clinical Trial.

ObjectivesTo determine the effectiveness of a customized sound therapy and compare its effectiveness to that of masking with broadband noise.MethodsSubjects were randomized to receive either customized sound therapy or broadband noise for 2 hours per day for 3 months and then switched to the other treatment after a washout period. The outcome variables were tinnitus loudness (scored 0-10), Tinnitus Handicap Inventory (THI), Beck Anxiety Inventory (BAI), minimum masking levels (MML), and residual inhibition (RI).ResultsEighteen subjects completed the study. Mean age was 53 ± 11 years, and mean tinnitus duration was 118 ± 99 months. With customized sound therapy, mean loudness decreased from 6.4 ± 2.0 to 4.9 ± 1.9 ( P = .001), mean THI decreased from 42.8 ± 21.6 to 31.5 ± 20.3 ( P < .001), mean BAI decreased from 10.6 ± 10.9 to 8.3 ± 9.9 ( P = .01), and MML decreased from 22.3 ± 11.6 dB SL to 17.2 ± 10.6 dB SL ( P = .005). After 3 months of broadband noise therapy, only BAI and, to a lesser degree, MML decreased ( P = .003 and .04, respectively).ConclusionsCustomized sound therapy can decrease the loudness and THI scores of tinnitus patients, and the results may be superior to broadband noise