Timely diagnosis of movement disorders like Parkinson’s Disease (PD) improves quality of life. However, access to clinical diagnosis is limited in low-income countries. Here, we present PULSAR, a novel method for classifying individuals with or without PD from webcam-recorded videos of the finger-tapping task used in the Movement Disorder Society—Unified Parkinson’s Disease Rating Scale (MDS-UPDRS). PULSAR was trained and evaluated on data from 382 participants, including 183 self-reported PD patients. We used an adaptive graph convolutional neural network to dynamically learn task-specific spatio-temporal edges and enhanced it with a multi-stream convolution model to capture critical features like finger joint locations, tapping velocity, and acceleration of tapping. As video labels are self-reported, some non-PD labels may be undiagnosed cases. To address this, we used Positive Unlabeled (PU) Learning, which outperformed traditional supervised learning. PULSAR achieved 80.95% accuracy on the validation set and 71.29% mean accuracy (2.49% standard deviation) on an independent test set. We hope PULSAR can aid in accessible PD screening and that these techniques may extend to assessing disorders like ataxia and Huntington’s disease.

Localizing macromolecules in crowded cellular cryo-electron tomography (cryo-ET) images or tomograms is crucial for determining their in situ structures. Traditional template matching-based approaches for this task suffer from template-specific biases and have low throughput. Given these problems, learning-based solutions are necessary. However, the paucity of annotated data for training poses substantial challenges for such learning-based methods. Moreover, preparing extensively annotated cellular tomograms for training macromolecule localization methods is extremely time-consuming and burdensome due to the large volume and low signal-to-noise ratio of the tomograms. In this work, we developed TomoPicker, an annotation-efficient macromolecule localization method for tomograms. To achieve such annotation-efficiency, TomoPicker regards macromolecule localization as a voxel classification problem and solves it with two different positive-unlabeled learning approaches. We evaluated TomoPicker on two experimental cryo-ET datasets of crowded eukaryotic cells and one experimental dataset of relatively less crowded prokaryotic cell. We observed that, with only 10 annotated macromolecule locations, TomoPicker with positive unlabeled learning achieved a performance comparable to that of state-of-the-art supervised methods trained with several hundred annotations. In other words, TomoPicker achieved plausible segmentation with up to 98% less data compared with supervised learning-based methods. Furthermore, it demonstrated substantial improvements over existing learning-based macromolecule localization methods under sparse annotation scenarios.

MOTIVATION: With the recent breakthroughs in sequencing technology, phylogeny estimation at a larger scale has become a huge opportunity. For accurate estimation of large-scale phylogeny, substantial endeavor is being devoted in introducing new algorithms or upgrading current approaches. In this work, we endeavor to improve the Quartet Fiduccia and Mattheyses (QFM) algorithm to resolve phylogenetic trees of better quality with better running time. QFM was already being appreciated by researchers for its good tree quality, but fell short in larger phylogenomic studies due to its excessively slow running time. RESULTS: We have re-designed QFM so that it can amalgamate millions of quartets over thousands of taxa into a species tree with a great level of accuracy within a short amount of time. Named "QFM Fast and Improved (QFM-FI)", our version is 20 000× faster than the previous version and 400× faster than the widely used variant of QFM implemented in PAUP* on larger datasets. We have also provided a theoretical analysis of the running time and memory requirements of QFM-FI. We have conducted a comparative study of QFM-FI with other state-of-the-art phylogeny reconstruction methods, such as QFM, QMC, wQMC, wQFM, and ASTRAL, on simulated as well as real biological datasets. Our results show that QFM-FI improves on the running time and tree quality of QFM and produces trees that are comparable with state-of-the-art methods. AVAILABILITY AND IMPLEMENTATION: QFM-FI is open source and available at https://github.com/sharmin-mim/qfm_java.