Normalized Power Prior Bayesian Analysis

The elicitation of power prior distributions is based on the availability of historical data, and is realized by raising the likelihood function of the historical data to a fractional power. However, an arbitrary positive constant before the like- lihood function of the historical data could change the inferential results when one uses the original power prior. This raises a question that which likelihood function should be used, one from raw data, or one from a su±cient-statistics. We propose a normalized power prior that can better utilize the power parameter in quantifying the heterogeneity between current and historical data. Furthermore, when the power parameter is random, the optimality of the normalized power priors is shown in the sense of maximizing Shannon's mutual information. Some comparisons between the original and the normalized power prior approaches are made and a water-quality monitoring data is used to show that the normalized power prior is more sensible.Bayesian analysis, historical data, normalized power prior, power prior, prior elicitation, Shannon's mutual information.

Reversing cooling flows with AGN jets: shock waves, rarefaction waves, and trailing outflows

The cooling flow problem is one of the central problems in galaxy clusters, and active galactic nucleus (AGN) feedback is considered to play a key role in offsetting cooling. However, how AGN jets heat and suppress cooling flows remains highly debated. Using an idealized simulation of a cool-core cluster, we study the development of central cooling catastrophe and how a subsequent powerful AGN jet event averts cooling flows, with a focus on complex gasdynamical processes involved. We find that the jet drives a bow shock, which reverses cooling inflows and overheats inner cool core regions. The shocked gas moves outward in a rarefaction wave, which rarefies the dense core and adiabatically transports a significant fraction of heated energy to outer regions. As the rarefaction wave propagates away, inflows resume in the cluster core, but a trailing outflow is uplifted by the AGN bubble, preventing gas accumulation and catastrophic cooling in central regions. Inflows and trailing outflows constitute meridional circulations in the cluster core. At later times, trailing outflows fall back to the cluster centre, triggering central cooling catastrophe and potentially a new generation of AGN feedback. We thus envisage a picture of cool cluster cores going through cycles of cooling-induced contraction and AGN-induced expansion. This picture naturally predicts an anti-correlation between the gas fraction (or X-ray luminosity) of cool cores and the central gas entropy, which may be tested by X-ray observations.Comment: Slightly revised version, accepted for publication in MNRAS. 14 pages, 10 figure

A Multiresolution PDE-Based Deformable Surface for Medical Imaging Applications

We recently developed a multiresolution PDE-based deformable surface whose deformation behavior is governed by partial differential equations (PDEs) such as the weighted minimal surface flow. Comparing with the level-set approach, our new model has better control of the mesh quality and model resolution, and is much simpler to implement since all the computations are local. The new deformable model is very useful for a variety of medical imaging applications including boundary reconstruction, surface visualization, data segmentation, and topology discovery. In this paper, we demonstrate both the accuracy and robustness of our model on areas such as medical image segmentation through a number of experiments on both real (MRI/CT) and synthetic volumetric datasets

Randomized Kolmogorov and Linear Widths on Generalized Besov Classes with Mixed Smoothness

AbstractIn this paper, we study the Kolmogorov and the linear widths on the generalized Besov sov classes , BpθΩ with mixed smoothness in the Monte Carlo setting. Applying the discretization technique and some properties of pseudo-s-scale, we determine the exact asymptotic orders of the Kolmogorov and the linear widths for some values of the parameters p,q,θ

ITongue : an iPhone app for personal health monitoring based on tongue image

Principle Investigators: Ye Duan and Dong Xu, Department of Computer Science, College of Engineering, University of Missouri.The "iTongue" system is able to let the users get their health status within a few minutes. What the users need to do is use their mobile device to take a picture of his/her tongue and the iTongue system will be able to diagnose his/her health status and send back the information. This system consists of the client side and the server side program. The client side of the system is an ios app that can run on any ios device with cameras.MU Interdisciplinary Innovations Fun

RNA-seq with RNase H-based ribosomal RNA depletion specifically designed for C. elegans

Here we describe a rRNA depletion protocol based on RNase H digestion using antisense oligonucleotides (ASOs) specifically designed for C. elegans cytoplasmic rRNA (Fig. 1A). We suggest that this rRNA depletion protocol is applicable to RNA-seq applications where the yield of mRNA enrichment should be independent of poly(A) status, or any application which benefits from the removal of rRNA sequences, such ribosome profiling, or sequencing of non-coding RNAs other than rRNA