45 research outputs found
Parasitic Effect Compensation Method for IGBT ON-State Voltage Measurement in Traction Inverter Application
Hamiltonian Transformation for Band Structure Calculations
First-principles electronic band structure calculations are essential for
understanding periodic systems in condensed matter physics and materials
science. We propose an accurate and parameter-free method, called Hamiltonian
transformation (HT), to calculate band structures in both density functional
theory (DFT) and post-DFT calculations with plane-wave basis sets. The cost of
HT is independent of the choice of the density functional and scales as
, where and are the number of
electrons and the number of -points. Compared to the widely used
Wannier interpolation (WI), HT adopts an eigenvalue transformation to construct
a spatial localized representation of the spectrally truncated Hamiltonian. HT
also uses a non-iterative algorithm to change the basis sets to circumvent the
construction of the maximally localized Wannier functions. As a result, HT can
significantly outperform WI in terms of the accuracy of the band structure
calculation. We also find that the eigenvalue transformation can be of
independent interest, and can be used to improve the accuracy of the WI for
systems with entangled bands.Comment: 5 pages, 4 figure
Modeling Rett Syndrome Using TALEN-Edited MECP2 Mutant Cynomolgus Monkeys
Gene-editing technologies have made it feasible to create nonhuman primate models for human genetic disorders. Here, we report detailed genotypes and phenotypes of TALEN-edited MECP2 mutant cynomolgus monkeys serving as a model for a neurodevelopmental disorder, Rett syndrome (RTT), which is caused by loss-of-function mutations in the human MECP2 gene. Male mutant monkeys were embryonic lethal, reiterating that RTT is a disease of females. Through a battery of behavioral analyses, including primate-unique eye-tracking tests, in combination with brain imaging via MRI, we found a series of physiological, behavioral, and structural abnormalities resembling clinical manifestations of RTT. Moreover, blood transcriptome profiling revealed that mutant monkeys resembled RTT patients in immune gene dysregulation. Taken together, the stark similarity in phenotype and/or endophenotype between monkeys and patients suggested that gene-edited RTT founder monkeys would be of value for disease mechanistic studies as well as development of potential therapeutic interventions for RTT
Smaller is better: drift in gaze measurements due to pupil dynamics.
Camera-based eye trackers are the mainstay of eye movement research and countless practical applications of eye tracking. Recently, a significant impact of changes in pupil size on gaze position as measured by camera-based eye trackers has been reported. In an attempt to improve the understanding of the magnitude and population-wise distribution of the pupil-size dependent shift in reported gaze position, we present the first collection of binocular pupil drift measurements recorded from 39 subjects. The pupil-size dependent shift varied greatly between subjects (from 0.3 to 5.2 deg of deviation, mean 2.6 deg), but also between the eyes of individual subjects (0.1 to 3.0 deg difference, mean difference 1.0 deg). We observed a wide range of drift direction, mostly downward and nasal. We demonstrate two methods to partially compensate the pupil-based shift using separate calibrations in pupil-constricted and pupil-dilated conditions, and evaluate an improved method of compensation based on individual look-up-tables, achieving up to 74% of compensation
Data from: Smaller is better: drift in gaze measurements due to pupil dynamics
Camera-based eye trackers are the mainstay of eye movement research and countless practical applications of eye tracking. Recently, a significant impact of changes in pupil size on gaze position as measured by camera-based eye trackers has been reported. In an attempt to improve the understanding of the magnitude and population-wise distribution of the pupil-size dependent shift in reported gaze position, we present the first collection of binocular pupil drift measurements recorded from 39 subjects. The pupil-size dependent shift varied greatly between subjects (from 0.3 to 5.2 deg of deviation, mean 2.6 deg), but also between the eyes of individual subjects (0.1 to 3.0 deg difference, mean difference 1.0 deg). We observed a wide range of drift direction, mostly downward and nasal. We demonstrate two methods to partially compensate the pupil-based shift using separate calibrations in pupil-constricted and pupil-dilated conditions, and evaluate an improved method of compensation based on individual look-up-tables, achieving up to 74% of compensation
Eye tracking data from Drewes et al, PlosONE 2014
A tar/zipped matlab datafile (.mat), containing structured dat