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We present a personalized, comprehensive eye-tracking solution based on tracking higher-order Purkinje images, suited explicitly for eyeglasses-style AR and VR displays. Existing eye-tracking systems for near-eye applications are typically designed to work for an on-axis configuration and rely on pupil center and corneal reflections (PCCR) to estimate gaze with an accuracy of only about 0.5°to 1°. These are often expensive, bulky in form factor, and fail to estimate monocular accommodation, which is crucial for focus adjustment within the AR glasses. Our system independently measures the binocular vergence and monocular accommodation using higher-order Purkinje reflections from the eye, extending the PCCR based methods. We demonstrate that these reflections are sensitive to both gaze rotation and lens accommodation and model the Purkinje images’ behavior in simulation. We also design and fabricate a user-customized eye tracker using cheap off-the-shelf cameras and LEDs. We use an end-to-end convolutional neural network (CNN) for calibrating the eye tracker for the individual user, allowing for robust and simultaneous estimation of vergence and accommodation. Experimental results show that our solution, specifically catering to individual users, outperforms state-of-the-art methods for vergence and depth estimation, achieving an accuracy of 0.3782°and 1.108 cm respectively. 

Approximately 10% of the world’s population is at risk of schistosomiasis, a disease of poverty caused by theSchistosomaparasite. To facilitate drug discovery for this complex flatworm, we developed an automated high-content screen to quantify the multidimensional responses ofSchistosoma mansonipost-infective larvae (somules) to chemical insult. We describe an integrated platform to process worms at scale, collect time-lapsed, bright-field images, segment highly variable and touching worms, and then store, visualize, and query dynamic phenotypes. To demonstrate the methodology, we treated somules with seven drugs that generated diverse responses and evaluated 45 static and kinetic response descriptors relative to concentration and time. For compound screening, we used the Mahalanobis distance to compare multidimensional phenotypic effects induced by 1323 approved drugs. Overall, we characterize both known anti-schistosomals and identify new bioactives. Apart from facilitating drug discovery, the multidimensional quantification provided by this platform will allow mapping of chemistry to phenotype.

 

For southward interplanetary magnetic field (IMF) during local summer, the hemispherically integrated Poynting flux estimated by FAST‐satellite‐derived empirical models is significantly larger for the northern hemisphere (NH) than for the southern hemisphere (SH). In order to test whether the difference is statistically significant, the model uncertainties have been estimated by dividing the data sets for each hemisphere into two nonintersecting sets, and separately constructing the model using each of the four sets. The model uncertainty appears to be smaller than the estimated asymmetry. The asymmetry is mostly absent when the IMF is northward, except there is some evidence that it may actually reverse during local winter. The phenomena is coupled with what appears to be a more distinct two‐cell convection pattern in the NH, and a possibly greater cusp contribution in the SH. All this suggests an effect of magnetosphere‐ionosphere‐thermosphere coupling, probably related to asymmetries in Earth's geomagnetic field.

 

Drug‐induced liver injury is an important cause of non‐approval in drug development and the withdrawal of already approved drugs from the market. Screening human hepatic cell lines for toxicity has been used extensively to predict drug‐induced liver injury in preclinical drug development. Assessing hepatic‐cell health with more diverse markers will increase the value of in vitro assays and help predict the mechanism of toxicity. We describe three live cell‐based assays using HepG2 cells to measure cell health parameters indicative of hepatotoxicity. The first assay measures cellular ATP levels using luciferase. The second and third assays are multiparametric high‐content screens covering a panel of cell health markers including cell count, mitochondrial membrane potential and structure, nuclear morphology, vacuolar density, and reactive oxygen species and glutathione levels. © 2020 Wiley Periodicals LLC.

Basic Protocol 1: Measurement of cellular ATP content

Basic Protocol 2: High‐content analysis assay to assess cell count, mitochondrial membrane potential and structure, and reactive oxygen species

Basic Protocol 3: High‐content analysis assay to assess nuclear morphology, vacuoles, and glutathione content

Support Protocol 1: Subculturing and maintaining HepG2 cells

Support Protocol 2: Plating HepG2 cell line

Support Protocol 3: Transferring compounds by pin tool

Support Protocol 4: Generating dose‐response curves