University of Missouri

About: University of Missouri is a education organization based out in Columbia, Missouri, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 41427 authors who have published 83598 publications receiving 2911437 citations. The organization is also known as: Mizzou & Missouri-Columbia.

Joint source channel rate-distortion analysis for adaptive mode selection and rate control in wireless video coding

Abstract: We first develop a rate-distortion (R-D) model for DCT-based video coding incorporating the macroblock (MB) intra refreshing rate. For any given bit rate and intra refreshing rate, this model is capable of estimating the corresponding coding distortion even before a video frame is coded. We then present a theoretical analysis of the picture distortion caused by channel errors and the subsequent inter-frame propagation. Based on this analysis, we develop a statistical model to estimate such channel errors induced distortion for different channel conditions and encoder settings. The proposed analytic model mathematically describes the complex behavior of channel errors in a video coding and transmission system. Unlike other experimental approaches for distortion estimation reported in the literature, this analytic model has very low computational complexity and implementation cost, which are highly desirable in wireless video applications. Simulation results show that this model is able to accurately estimate the channel errors induced distortion with a minimum delay in processing. Based on the proposed source coding R-D model and the analytic channel-distortion estimation, we derive an analytic solution for adaptive intra mode selection and joint source-channel rate control under time-varying wireless channel conditions. Extensive experimental results demonstrate that this scheme significantly improves the end-to-end video quality in wireless video coding and transmission.

eLearning: a review of Internet-based continuing medical education.

Abstract: Introduction: The objective was to review the effrct oflnternet-based continuing medical education (CME) interventions on physician pegormance and health care outcomes. Methods: Data sources included searches of MEDLINE (1 966 to January 20041, CINAHL (1982 to December 2003), ACP Journal Club (1991 to JulyIAugust 2003), and the Cochrane Database of Systematic Reviews (third quartel; 2003). Studies were included in the analyses if they were randomized controlled trials of Internet-based education in which participants were practicing health care professionals or health professionals in training. CME interventions were categorized according to the nature of the intervention, sample size, und other information about educational content and form&. Results: Sixteen studies met the eligibility criteria. Six studies generated positive changes in participant knowledge over traditional formats; tvdy three studies showed a positive change in practices. The remainder of the studies showed no difference in knowledge levels between Internet-based interventions and traditional formats for CME. Discussion: The results demonstrate that Internet-based CME programs are just as efective in imparting knowledge as traditional formats of CME. Little is known as to whether these positive changes in knowledge are translated into changes in practice. Subjective reports of change in physician behavior should be confirmed through chart review or other objective measures. Additional studies need to be peqormed to assess how long these new learned behaviors could be sustained. elearning will continue to evolve as new innovations and more interactive modes are incorporated into learning

Hierarchical Bayesian Models for Predicting The Spread of Ecological Processes

Abstract: There is increasing interest in predicting ecological processes. Methods to accomplish such predictions must account for uncertainties in observation, sampling, models, and parameters. Statistical methods for spatiotemporal processes are powerful, yet difficult to implement in complicated high-dimensional settings. However, recent advances in hierarchical formulations for such processes can be utilized for ecological prediction. These formulations are able to account for the various sources of uncertainty and can incorporate scientific judgment in a probabilistically consistent manner. In particular, analytical diffusion models can serve as motivation for the hierarchical model for invasive species. We demonstrate by example that such a framework can be utilized to predict, spatially and temporally, the relative population abundance of House Finches over the eastern United States. Corresponding Editor (ad hoc): J. S. Clark.

Rapid induction of inflammatory lipid mediators by the inflammasome in vivo

Abstract: Detection of microbial products by host inflammasomes is an important mechanism of innate immune surveillance. Inflammasomes activate the caspase-1 (CASP1) protease, which processes the cytokines interleukin (IL)-1β and IL-18, and initiates a lytic host cell death called pyroptosis. To identify novel CASP1 functions in vivo, we devised a strategy for cytosolic delivery of bacterial flagellin, a specific ligand for the NAIP5 (NLR family, apoptosis inhibitory protein 5)/NLRC4 (NLR family, CARD-domain-containing 4) inflammasome. Here we show that systemic inflammasome activation by flagellin leads to a loss of vascular fluid into the intestine and peritoneal cavity, resulting in rapid (less than 30 min) death in mice. This unexpected response depends on the inflammasome components NAIP5, NLRC4 and CASP1, but is independent of the production of IL-1β or IL-18. Instead, inflammasome activation results, within minutes, in an 'eicosanoid storm'--a pathological release of signalling lipids, including prostaglandins and leukotrienes, that rapidly initiate inflammation and vascular fluid loss. Mice deficient in cyclooxygenase-1, a critical enzyme in prostaglandin biosynthesis, are resistant to these rapid pathological effects of systemic inflammasome activation by either flagellin or anthrax lethal toxin. Inflammasome-dependent biosynthesis of eicosanoids is mediated by the activation of cytosolic phospholipase A(2) in resident peritoneal macrophages, which are specifically primed for the production of eicosanoids by high expression of eicosanoid biosynthetic enzymes. Our results therefore identify eicosanoids as a previously unrecognized cell-type-specific signalling output of the inflammasome with marked physiological consequences in vivo.