Explain Variance of Prediction in Variational Time Series Models for Clinical Deterioration Prediction

Missingness and measurement frequency are two sides of the same coin. How frequent should we measure clinical variables and conduct laboratory tests? It depends on many factors such as the stability of patient conditions, diagnostic process, treatment plan and measurement costs. The utility of measurements varies disease by disease, patient by patient. In this study we propose a novel view of clinical variable measurement frequency from a predictive modeling perspective, namely the measurements of clinical variables reduce uncertainty in model predictions. To achieve this goal, we propose variance SHAP with variational time series models, an application of Shapley Additive Expanation(SHAP) algorithm to attribute epistemic prediction uncertainty. The prediction variance is estimated by sampling the conditional hidden space in variational models and can be approximated deterministically by delta's method. This approach works with variational time series models such as variational recurrent neural networks and variational transformers. Since SHAP values are additive, the variance SHAP of binary data imputation masks can be directly interpreted as the contribution to prediction variance by measurements. We tested our ideas on a public ICU dataset with deterioration prediction task and study the relation between variance SHAP and measurement time intervals

Enabling Feedback-Free MIMO Transmission for FD-RAN: A Data-driven Approach

To enhance flexibility and facilitate resource cooperation, a novel fully-decoupled radio access network (FD-RAN) architecture is proposed for 6G. However, the decoupling of uplink (UL) and downlink (DL) in FD-RAN makes the existing feedback mechanism ineffective. To this end, we propose an end-to-end data-driven MIMO solution without the conventional channel feedback procedure. Data-driven MIMO can alleviate the drawbacks of feedback including overheads and delay, and can provide customized precoding design for different BSs based on their historical channel data. It essentially learns a mapping from geolocation to MIMO transmission parameters. We first present a codebook-based approach, which selects transmission parameters from the statistics of discrete channel state information (CSI) values and utilizes integer interpolation for spatial inference. We further present a non-codebook-based approach, which 1) derives the optimal precoder from the singular value decomposition (SVD) of the channel; 2) utilizes variational autoencoder (VAE) to select the representative precoder from the latent Gaussian representations; and 3) exploits Gaussian process regression (GPR) to predict unknown precoders in the space domain. Extensive simulations are performed on a link-level 5G simulator using realistic ray-tracing channel data. The results demonstrate the effectiveness of data-driven MIMO, showcasing its potential for application in FD-RAN and 6G

Text-guided Eyeglasses Manipulation with Spatial Constraints

Virtual try-on of eyeglasses involves placing eyeglasses of different shapes and styles onto a face image without physically trying them on. While existing methods have shown impressive results, the variety of eyeglasses styles is limited and the interactions are not always intuitive or efficient. To address these limitations, we propose a Text-guided Eyeglasses Manipulation method that allows for control of the eyeglasses shape and style based on a binary mask and text, respectively. Specifically, we introduce a mask encoder to extract mask conditions and a modulation module that enables simultaneous injection of text and mask conditions. This design allows for fine-grained control of the eyeglasses' appearance based on both textual descriptions and spatial constraints. Our approach includes a disentangled mapper and a decoupling strategy that preserves irrelevant areas, resulting in better local editing. We employ a two-stage training scheme to handle the different convergence speeds of the various modality conditions, successfully controlling both the shape and style of eyeglasses. Extensive comparison experiments and ablation analyses demonstrate the effectiveness of our approach in achieving diverse eyeglasses styles while preserving irrelevant areas.Comment: Revised version: add some experiment

The Distance Between Exons and Alu Elements Influences RNA Circularization Efficiency

Circular RNA (circRNA) is a category of RNA that is created when the spliceosome back-splices an exon, thereby forming an RNA covalent circle. A few circRNAs have been shown to have regulatory functions, but the functions of most circRNAs are not known. Previous studies have demonstrated that repetitive elements flanking the exon(s), such as Alu elements, facilitate circularization, and have identified the minimal size of repetitive elements needed to drive circularization. We studied how the distance between exon splice donors/acceptors and Alu elements affects the efficiency of RNA circularization. To create the distance gradient, we inserted and/or deleted sequences between the splice donors/acceptor and Alu elements. We engineered the circular RNA so that it would express GFP after circularization. To measure the circularization efficiency, we conducted Western blots and Northern blots on the proteins and RNA harvested from cells. We showed that in HEK293 cells the distance of the repetitive element upstream of the exon has a large effect on circularization, while the distance downstream has little effect. Combining these observations, we created a minimal construct that can be circularized efficiently and expressed much more protein than our original construct. Overall, our study further contributed to the understanding of the cis elements that affect circular RNA formation in vivo, and design of vectors to efficiently express proteins from very stable RNAs.Bachelor of Scienc