Compliance with San Francisco's flavoured tobacco sales prohibition.

BackgroundIn June 2018, San Francisco voters upheld the first comprehensive prohibition on sales of flavoured tobacco products (all products including menthol, everywhere in the city with no exceptions).MethodsThis paper used data collected by the San Francisco Department of Public Health as part of its implementation and enforcement of San Francisco's city-wide ban on the sale of flavoured tobacco products. Every licensed tobacco retailer was visited and inspected. The San Francisco Department of Public Health and volunteers conducted an educational campaign from September 2018 to December 2018, including emailing all licensed tobacco retailers about the law, mailing a fact sheet poster, conducting four listening sessions and visiting permitted tobacco retailers to educate them about the law and solicit questions.ResultsCompliance inspections started in December 2018, which found that compliance was 17%. Compliance increased in January 2019 and averaged 80% between January 2019 and December 2019. After the phase-in period, all retailers were visited as part of routine inspections. This effort resulted in 80% compliance.ConclusionIncluding retailer education prior to enforcement can result in compliance with a comprehensive ban on the sale of menthol and other flavoured tobacco products

Compliance with San Francisco's flavoured tobacco sales prohibition.

BackgroundIn June 2018, San Francisco voters upheld the first comprehensive prohibition on sales of flavoured tobacco products (all products including menthol, everywhere in the city with no exceptions).MethodsThis paper used data collected by the San Francisco Department of Public Health as part of its implementation and enforcement of San Francisco's city-wide ban on the sale of flavoured tobacco products. Every licensed tobacco retailer was visited and inspected. The San Francisco Department of Public Health and volunteers conducted an educational campaign from September 2018 to December 2018, including emailing all licensed tobacco retailers about the law, mailing a fact sheet poster, conducting four listening sessions and visiting permitted tobacco retailers to educate them about the law and solicit questions.ResultsCompliance inspections started in December 2018, which found that compliance was 17%. Compliance increased in January 2019 and averaged 80% between January 2019 and December 2019. After the phase-in period, all retailers were visited as part of routine inspections. This effort resulted in 80% compliance.ConclusionIncluding retailer education prior to enforcement can result in compliance with a comprehensive ban on the sale of menthol and other flavoured tobacco products

Vision-based vehicle tracking (ViVet)

The use of computer vision has started to make its way in the field of Traffic surveillance. Through video image processing, valuable traffic data such as vehicle count and density is generated automatically with minimal human intervention. To date, this technology has been adopted by many countries to break away from the manual surveillance system and the problems encountered by the conventional in-pavement loops. However, here in the Philippines, this technology has not yet been adopted. More so, the performance of vehicle tracking approaches when implemented on Philippine roadways is still questionable due to unforeseen localized conditions. In this regard, ViVeT endeavors the implementation of a multiple vehicle tracking system based on Philippine roadways. The study focuses on implementing a system that can track vehicles under roadways subject to varying levels of occlusion, shadow and luminance taking into consideration the localized factors relating to these identified problems. The system mainly consists of a video acquisition and a tracking module. Prior to tracking, a still digital video camera records a video footage of a roadway and converts it to an image sequence. The actual vehicle tracking then starts off with the processing of the image sequence to hypothesize and verify all possible locations of vehicles. With its successful implementation, the study can serve as a platform for traffic surveillance purposes as well as those applications that provide traffic information to motorist and commuters

SymForce: Symbolic Computation and Code Generation for Robotics

We present SymForce, a library for fast symbolic computation, code generation, and nonlinear optimization for robotics applications like computer vision, motion planning, and controls. SymForce combines the development speed and flexibility of symbolic math with the performance of autogenerated, highly optimized code in C++ or any target runtime language. SymForce provides geometry and camera types, Lie group operations, and branchless singularity handling for creating and analyzing complex symbolic expressions in Python, built on top of SymPy. Generated functions can be integrated as factors into our tangent-space nonlinear optimizer, which is highly optimized for real-time production use. We introduce novel methods to automatically compute tangent-space Jacobians, eliminating the need for bug-prone handwritten derivatives. This workflow enables faster runtime code, faster development time, and fewer lines of handwritten code versus the state-of-the-art. Our experiments demonstrate that our approach can yield order of magnitude speedups on computational tasks core to robotics. Code is available at https://github.com/symforce-org/symforce.Comment: 10 pages, 5 figures. RSS 202

Within-host evolutionary dynamics of seasonal and pandemic human influenza A viruses in young children.

The evolution of influenza viruses is fundamentally shaped by within-host processes. However, the within-host evolutionary dynamics of influenza viruses remain incompletely understood, in part because most studies have focused on infections in healthy adults based on single timepoint data. Here, we analysed the within-host evolution of 82 longitudinally-sampled individuals, mostly young children, infected with A/H1N1pdm09 or A/H3N2 viruses between 2007 and 2009. For A/H1N1pdm09 infections during the 2009 pandemic, nonsynonymous minority variants were more prevalent than synonymous ones. For A/H3N2 viruses in young children, early infection was dominated by purifying selection. As these infections progressed, nonsynonymous variants typically increased in frequency even when within-host virus titres decreased. Unlike the short-lived infections of adults where de novo within-host variants are rare, longer infections in young children allow for the maintenance of virus diversity via mutation-selection balance creating potentially important opportunities for within-host virus evolution

Within-host evolutionary dynamics of seasonal and pandemic human influenza a viruses in young children

The evolution of influenza viruses is fundamentally shaped by within-host processes. However, the within-host evolutionary dynamics of influenza viruses remain incompletely understood, in part because most studies have focused on infections in healthy adults based on single timepoint data. Here, we analysed the within-host evolution of 82 longitudinally-sampled individuals, mostly young children, infected with A/H1N1pdm09 or A/H3N2 viruses between 2007 and 2009. For A/H1N1pdm09 infections during the 2009 pandemic, nonsynonymous minority variants were more prevalent than synonymous ones. For A/H3N2 viruses in young children, early infection was dominated by purifying selection. As these infections progressed, nonsynonymous variants typically increased in frequency even when within-host virus titres decreased. Unlike the short-lived infections of adults where de novo within-host variants are rare, longer infections in young children allow for the maintenance of virus diversity via mutation-selection balance creating potentially important opportunities for within-host virus evolution