Presentations

"Fake news" and viral content

In November 2017, I gave a short talk at the AppNexus summit with my colleague Laura Yu about the commonalities between fake news and low quality viral content websites, and how they all try to make money with ads. Sorry it's not the most detailed ever, we have to be mindful of the game theory involved in adversarial data science, but I hope you'll still find it interesting. Our most striking result (which we can only present in generalities) is that the patterns of traffic generation appear similar, regardless of the sort of scheme being used.

Kafka and Spark Streaming

In 2015 I gave a talk about one of the ways we use Spark Streaming at AppNexus to stop non-human traffic. Although the algorithm I describe in this talk is not exactly the most sophisticated, it's simple, quick, and works on all 120 billion daily events we see at AppNexus (or about 300k queries per second!). As of 2018 this figure has reached 300 billion requests per day, and the code is still running!

Publications

Identification of a novel endoplasmic reticulum stress response element regulated by XBP1.

Misiewicz M, Déry MA, Foveau B, Jodoin J, Ruths D, LeBlanc AC.  Journal of Biological Chemistry. 288. July 12 2013.
Understanding when and where certain genes are activated in the life-cycle of a cell, in response to which developmental programs and what external stresses is a very important part of molecular biology and modern medicine. Before this research, we noticed an unusual sequence of DNA in the promoter of the prion gene, and we believed it could be important for regulating prion expression in response to stress. Our previous work showed that the prion gene, outside of its role in famous diseases such as mad cow disease, does something important to protect neurons from Endoplasimc Reticulum stress, which commonly occurs in cancers and other disease states. In this work, we used bioinformatic techniques (BLAST, Regex and Hidden Markov Models) search the entire human genome for this sequence. We found several dozen exact matches. Using a series of _in vitro_ and _in vivo_ assays, we confirmed that the genes we found were in fact regulated by our novel element, meaning the way in which a cell responds to stress is now better understood. These results may possibly explain some of the discoveries in our previous paper.

Loss of Anti-Bax Function in Gerstmann-Sträussler-Scheinker Syndrome-Associated Prion Protein Mutants.

Jodoin J, Misiewicz M, Makhijani P, Giannopoulos PN, Hammond J, Goodyer CG, LeBlanc AC.  PLOS One. August 14 2009.
This study was a systematic analysis of mutations in the prion gene that seem to interfere with its normal function in protecting neurons from stressful situations. Previous work showed that the prion protein is important for protecting neurons and other cells from stressful situations. Here, we figured out which parts of the prion gene are apparently responsible for this protective effect, and when the protective effect is absent in certain prion diseases.

Github Projects

I enjoy Spark, Scala and functional programming. Check out my Github for some small examples of my work in Python and Scala. Also I've got some other projects saved there too.