3 research outputs found
Music Recommendations in Hyperbolic Space: An Application of Empirical Bayes and Hierarchical Poincar\'e Embeddings
Matrix Factorization (MF) is a common method for generating recommendations,
where the proximity of entities like users or items in the embedded space
indicates their similarity to one another. Though almost all applications
implicitly use a Euclidean embedding space to represent two entity types,
recent work has suggested that a hyperbolic Poincar\'e ball may be more well
suited to representing multiple entity types, and in particular, hierarchies.
We describe a novel method to embed a hierarchy of related music entities in
hyperbolic space. We also describe how a parametric empirical Bayes approach
can be used to estimate link reliability between entities in the hierarchy.
Applying these methods together to build personalized playlists for users in a
digital music service yielded a large and statistically significant increase in
performance during an A/B test, as compared to the Euclidean model
Exercise-induced increases in cell free DNA in human plasma originate predominantly from cells of the haematopoietic lineage
The role of cell free DNA (cfDNA) has been intensively discussed under various pathological conditions and after acute bouts of exercise. To date, there is still no conclusive evidence concerning the cellular origin of cfDNA and the entire mechanism leading to elevated cfDNA concentrations in human plasma and serum. Here, we investigated the cellular origin of cfDNA in sex-mismatched haematopoietic stem cell transplantation (HSCT) and liver transplantation (LT) patients by determining the relative proportion of Y-chromosomal to total nuclear cfDNA. Total nuclear cfDNA and Y-chromosomal cfDNA concentrations were determined in blood plasma before and after an incremental exercise test via quantitative real-time PCR (qPCR). Female HSCT patients showed high proportions of Y-chromosomal cfDNA. Both total nuclear and Y-chromosomal cfDNA increased significantly and in a highly correlated fashion due to exercise. In male HSCT patients with female donors less than 10% of the cfDNA was of Y-chromosomal origin at any point in time and even though the total amount of cfDNA increased during exercise, no increases in Y-chromosomal DNA could be detected. The percentage of Y-chromosomal cfDNA in female LT patients with male donors was very low and levels remained unchanged during exercise. This indicates that cells not derived from the bone marrow, in this case transplanted liver cells, represented only a minor fraction of cfDNA in blood plasma and were not released during acute physical exercise. Even though many physiological conditions may be altered in transplant patients versus healthy people, our results strongly suggest that cells from the haematopoietic lineage are the main source of cfDNA released during acute bouts of exercise
Software Carpentry: Version Control with Git
A half-day introduction to version control with Git and GitHub for researchers, developed and maintained by the Software Carpentry team