The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Juliane Liepe - One of the best experts on this subject based on the ideXlab platform.
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inference of random walk models to describe leukocyte migration
Physical Biology, 2015Co-Authors: Phoebe J M Jones, Harriet B Taylor, Laurence Bugeon, Magaret J Dallman, Bernard Pereira, Michael P H Stumpf, Juliane LiepeAbstract:While the majority of cells in an organism are static and remain relatively immobile in their tissue, migrating cells occur commonly during developmental processes and are crucial for a functioning immune response. The mode of migration has been described in terms of various types of random walks. To understand the details of the migratory behaviour we rely on mathematical models and their calibration to experimental data. Here we propose an approximate Bayesian inference scheme to calibrate a class of random walk models characterized by a specific, parametric particle re-orientation mechanism to Observed Trajectory data. We elaborate the concept of transition matrices (TMs) to detect random walk patterns and determine a statistic to quantify these TM to make them applicable for inference schemes. We apply the developed pipeline to in vivo Trajectory data of macrophages and neutrophils, extracted from zebrafish that had undergone tail transection. We find that macrophage and neutrophils exhibit very distinct biased persistent random walk patterns, where the strengths of the persistence and bias are spatio-temporally regulated. Furthermore, the movement of macrophages is far less persistent than that of neutrophils in response to wounding.
Harriet B Taylor - One of the best experts on this subject based on the ideXlab platform.
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inference of random walk models to describe leukocyte migration
Physical Biology, 2015Co-Authors: Phoebe J M Jones, Harriet B Taylor, Laurence Bugeon, Magaret J Dallman, Bernard Pereira, Michael P H Stumpf, Juliane LiepeAbstract:While the majority of cells in an organism are static and remain relatively immobile in their tissue, migrating cells occur commonly during developmental processes and are crucial for a functioning immune response. The mode of migration has been described in terms of various types of random walks. To understand the details of the migratory behaviour we rely on mathematical models and their calibration to experimental data. Here we propose an approximate Bayesian inference scheme to calibrate a class of random walk models characterized by a specific, parametric particle re-orientation mechanism to Observed Trajectory data. We elaborate the concept of transition matrices (TMs) to detect random walk patterns and determine a statistic to quantify these TM to make them applicable for inference schemes. We apply the developed pipeline to in vivo Trajectory data of macrophages and neutrophils, extracted from zebrafish that had undergone tail transection. We find that macrophage and neutrophils exhibit very distinct biased persistent random walk patterns, where the strengths of the persistence and bias are spatio-temporally regulated. Furthermore, the movement of macrophages is far less persistent than that of neutrophils in response to wounding.
Kento Miyajima - One of the best experts on this subject based on the ideXlab platform.
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measurement of head mounted display s latency in rotation and side effect caused by lag compensation by simultaneous observation an example result using oculus rift dk2
IEEE Virtual Reality Conference, 2016Co-Authors: Ryugo Kijima, Kento MiyajimaAbstract:Latency is an important specification of the Head Mounted Display (HMD). In this paper, the authors proposed the measurement methods to evaluate the average latency as well as the effects/ side effects of the lag compensation. The Oculus Rift DK2 was selected for measurement. The results showed that the average latency of an DK2 without compensation was about 26.3 ms and that with full compensation was 1 ms. The rest part of the dynamic response was Observed and evaluated by subtracting the measured latency from the Observed Trajectory. The side effect of Timewarp was Observed as the spike like angular error.
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VR - Measurement of Head Mounted Display's latency in rotation and side effect caused by lag compensation by simultaneous observation — An example result using Oculus Rift DK2
2016 IEEE Virtual Reality (VR), 2016Co-Authors: Ryugo Kijima, Kento MiyajimaAbstract:Latency is an important specification of the Head Mounted Display (HMD). In this paper, the authors proposed the measurement methods to evaluate the average latency as well as the effects/ side effects of the lag compensation. The Oculus Rift DK2 was selected for measurement. The results showed that the average latency of an DK2 without compensation was about 26.3 ms and that with full compensation was 1 ms. The rest part of the dynamic response was Observed and evaluated by subtracting the measured latency from the Observed Trajectory. The side effect of Timewarp was Observed as the spike like angular error.
David D Meisel - One of the best experts on this subject based on the ideXlab platform.
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statistical and fragmentation properties of the micrometeoroid flux Observed at arecibo
Journal of Geophysical Research, 2009Co-Authors: S J Briczinski, J D Mathews, David D MeiselAbstract:[1] The micrometeor observations performed using the 430 MHz Arecibo Observatory radar have proven to be crucial for the understanding of meteoric effects on the aeronomy of the upper atmosphere. Meteors Observed during the February 2001, 2006, and 2007 campaigns have been analyzed with a fast Fourier transform periodic search algorithm that automatically and uniformly detects meteor events between altitudes of 80 and 142 km. We present a description of the new technique used to detect meteors as well as the meteoroid parameters: altitude profiles, radial speeds, and decelerations. We also note the expected correlation between the radar transmitted power and the Observed meteor event rate. The large number of events has enabled us to statistically estimate the average mass density of the Observed population indicating that our detected events are generally cometary (1 g/cm3) and not asteroidal (3 g/cm3) in origin. Additionally, many meteor events are Observed in which the radar meteor disappears from one radar pulse to the next (i.e., in 1 ms). We interpret this as indicative of the catastrophic destruction of the meteoroid. Until destruction, these events appear to undergo only minor ablation of their volatile components over the Observed Trajectory. As with a major fraction of all events recorded, the meteoroids that disappear in a terminal event show linear decelerations before their abrupt disappearance. This apparently low ablative mass deposition process may play an important role in the composition (aeronomy) of the upper atmosphere, as it likely produces submicron-sized particles rather than the atom level products of ablation. First results on the altitude, speed, and mass distributions of terminal event meteoroids are given yielding some clues on the physics of the terminal event. Finally, the statistics of those events that yield no deceleration are compared statistically with those that exhibit deceleration with the conclusion that both groups are statistically the same. We further conclude that along with low signal-to-noise ratio and short echo duration, fragmentation of this group of particles is a primary cause of the inability to determine deceleration.
Phoebe J M Jones - One of the best experts on this subject based on the ideXlab platform.
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inference of random walk models to describe leukocyte migration
Physical Biology, 2015Co-Authors: Phoebe J M Jones, Harriet B Taylor, Laurence Bugeon, Magaret J Dallman, Bernard Pereira, Michael P H Stumpf, Juliane LiepeAbstract:While the majority of cells in an organism are static and remain relatively immobile in their tissue, migrating cells occur commonly during developmental processes and are crucial for a functioning immune response. The mode of migration has been described in terms of various types of random walks. To understand the details of the migratory behaviour we rely on mathematical models and their calibration to experimental data. Here we propose an approximate Bayesian inference scheme to calibrate a class of random walk models characterized by a specific, parametric particle re-orientation mechanism to Observed Trajectory data. We elaborate the concept of transition matrices (TMs) to detect random walk patterns and determine a statistic to quantify these TM to make them applicable for inference schemes. We apply the developed pipeline to in vivo Trajectory data of macrophages and neutrophils, extracted from zebrafish that had undergone tail transection. We find that macrophage and neutrophils exhibit very distinct biased persistent random walk patterns, where the strengths of the persistence and bias are spatio-temporally regulated. Furthermore, the movement of macrophages is far less persistent than that of neutrophils in response to wounding.
