Protein posttranslational modifications (PTMs) play essential roles inthe regulation of almost all biological processes, ranging from DNAreplication and gene expression to metabolism. The dysregulation ofproteins PTMs often leads to human diseases such as cancer andneurodegenerative diseases. Therefore, it is of great importance toreveal the biological significance of protein PTMs and their regulatorymechanisms. Benefiting from the rapid development of massspectrometry technology, the number of known PTMs has increasedrapidly. However, only a handful of protein PTMs have beenextensively studied, while the cellular mechanisms and functions ofmany other PTMs, particularly those newly identified ones, remainspoorly understood. In this talk, I will present the new strategies anddiscoveries on the biological significance and regulation mechanismof several novel protein PTMs.

The immune response is a hallmark of cancer playingcritical roles in both pathogen defense and tumorprogression, operating through intracellular protein-proteininteraction networks organized in space and time. Abnormalprotein-protein interactions and signaling activations lead todysregulated cell-cell interactions and diseases. By usingproximity labeling mediated by engineered ascorbic acidperoxidase (APEX) and genetic mouse models, we uncoveredprotein complexes that are essential for antiviralimmuneactivation,cancer metastasis, immune cell-state transitionand cell-cell interactions in the tumor microenvironment. Inlight of the unsurpassable flexibility and spatiotemporalprecision to manipulate cell physiology, optogenetics hasbeen gaining rapid momentum in both neuronal cells andnon-excitable cells. To modulate immune cell function at ahigh spatiotemporal resolution in vivo, we devised a series ofnano-optogenetic tools for the optical control of effectorfunctions of immune cells and light-inducible tumor killing invivo. To continue my interests in immune-related diseases, lpropose to apply pooled screen, single cell and spatialtechnologies to dissect cell circuits and gene programsgoverning the progression of immune-related diseases.

Building intelligent visual systems is essential for the nextgeneration of artificial intelligence systems. It is a fundamentaltool for many disciplines and beneficial to various potentialapplicationssuch asautonomousdriving,robotics.surveillance,augmented reality, to name a few. An accurateand efficient intelligent visual system has a deep understandingof the scene, objects, and humans. lt can automaticallyunderstand the surrounding scenes. In general, 2D images and3D point clouds are the two most common data representationsin our daily life. Designing powerful image understanding andpoint cloud processing systems are two pillars of visualintelligence,enabling the artificial intelligence systems toand interact with the current status of theunderstandenvironment automatically. In this talk, I will first present ourefforts in designing modern neural systems for 2D imageunderstanding,including high-accuracy and high-efficiencysemantic parsing structures, and unified panoptic parsingarchitecture. Then, we go one step further to design neuralsystems for processing complex 3D scenes, includingsemantic-level and instance-level understanding. Further, weshow our latest works for unified 2D-3D reasoning frameworkswhich are fully based on self-attention mechanisms. In the end.the challenges, up-to-date progress, and promising futuredirections for building advanced intelligent visual systems will bediscussed.

Rail and urban transit systems often serve a large number of passengerson a daily basis and play an important role in supporting economicactivities. This presentation will discuss how to utilize modeling anddata analysis tools to improve our understanding and performanceof rail or urban transit systems. In particular, this presentation will firstdiscus data mining and modeling techniques for quantifying mobilitypatterns and demand prediction in rail/transit systems. Then, givencertain levels of demand information, pricing and service networkdesign problems in rail/transit systems will be presented. A fewexamples on game-theoretical models and network design models forpassenger-freight integrated transit/rail system will be illustrated. Inaddition, several empirical studies that examine the impacts of raildevelopment on accessibility, economy and equity will be discussedwhere the joint effect of rail development and megalopolis policy willalso be covered. In summary, this presentation illustrates with exampleshow modeling and analysis tools can be applied to rail and urban transitsystems for better policy and decision making.

Rapid advances in artificial intelligence (Al) have made itincreasingly applicable to support human work (eg. healthcare)However, the achievement of only accurate predictions of Alsystems is not sufficient for their deployment in practice. lf notcarefully designed with stakeholders, Al systems can exacerbateuser experience, and easily be abandoned. Instead, it is criticalthat these systems are designed to leverage the best of humanability, but also assist to overcome human limitations.In this talk, will introduce my work on creating two interactivesystems that augments a machine learning model with humanfeedback in the context of physical stroke rehabilitation therapy1) human-Al collaborative decision making on rehabilitationassessment for therapists and 2) human-robot collaborativerehabilitation therapy for post-stroke survivors. Then, I will shareinsights from the design, development, and evaluation ofcollaborative systems on rehabilitation with therapists andpost-stroke survivors. Finally, I will discuss emerging and futuredirections for my research, exploring core challenges of creatingeffective human-Al/robot collaborative systems.