Wenhui Wang

In this paper, we present the gated selfmatching networks for reading comprehension style question answering, which aims to answer questions from a given passage. We first match the question and passage with gated attention-based recurrent networks to obtain the question-aware passage representation. Then we propose a self-matching attention mechanism to refine the representation by matching the passage against itself, which effectively encodes information from the whole passage. We finally employ the pointer networks to locate the positions of answers from the passages. We conduct extensive experiments on the SQuAD dataset. The single model achieves 71.3% on the evaluation metrics of exact match on the hidden test set, while the ensemble model further boosts the results to 75.9%. At the time of submission of the paper, our model holds the first place on the SQuAD leaderboard for both single and ensemble model.

As an important embodiment of biomanipulation, injection of foreign materials (e.g., DNA, RNAi, sperm, protein, and drug compounds) into individual cells has significant implications in genetics, transgenics, assisted reproduction, and drug discovery. This paper presents a microrobotic system for fully automated zebrafish embryo injection, which overcomes the problems inherent in manual operation, such as human fatigue and large variations in success rates due to poor reproducibility. Based on computer vision and motion control, the microrobotic system performs injection at a speed of 15 zebrafish embryos (chorion unremoved) per minute, with a survival rate of 98% (n = 350 embryos), a success rate of 99% (n = 350 embryos), and a phenotypic rate of 98.5% (n = 210 embryos). The sample immobilization technique and microrobotic control method are applicable to other biological injection applications such as the injection of mouse oocytes/embryos and Drosophila embryos to enable high-throughput biological and pharmaceutical research.

3D rotation is one of many fundamental manipulations to cells and imperative in a wide range of applications in single cell analysis involving biology, chemistry, physics and medicine. In this article, we report a dielectrophoresis-based, on-chip manipulation method that can load and rotate a single cell for 3D cell imaging and multiple biophysical property measurements. To achieve this, we trapped a single cell in constriction and subsequently released it to a rotation chamber formed by four sidewall electrodes and one transparent bottom electrode. In the rotation chamber, rotating electric fields were generated by applying appropriate AC signals to the electrodes for driving the single cell to rotate in 3D under control. The rotation spectrum for in-plane rotation was used to extract the cellular dielectric properties based on a spherical single-shell model, and the stacked images of out-of-plane cell rotation were used to reconstruct the 3D cell morphology to determine its geometric parameters. We have tested the capabilities of our method by rotating four representative mammalian cells including HeLa, C3H10, B lymphocyte, and HepaRG. Using our device, we quantified the area-specific membrane capacitance and cytoplasm conductivity for the four cells, and revealed the subtle difference of geometric parameters (i.e., surface area, volume, and roughness) by 3D cell imaging of cancer cells and normal leukocytes. Combining microfluidics, dielectrophoresis, and microscopic imaging techniques, our electrorotation-on-chip (EOC) technique is a versatile method for manipulating single cells under investigation and measuring their multiple biophysical properties.