On the rendering and post-processing of simplified dynamic light fields with depth information

This paper studies the rendering and post-processing of a dynamic image-based representation called the simplified dynamic light fields (SDLF) (or plenoptic videos) with depth information. The user viewpoints are limited to a camera line to simplify the capturing and compression processes. By associating each image pixel with its depth value, methods for improving the rendering quality and detecting occlusions are proposed. Due to the limited sampling at depth discontinuities, adaptive lowpass filtering is applied to the detected occluded regions near object boundaries in order to suppress the aliasing artifacts. Rendering results using computer-generated images show that considerable improvement in rendering quality even for dynamic scenes with large depth variations.published_or_final_versio

An object-based approach to image/video-based synthesis and processing for 3-D and multiview televisions

This paper proposes an object-based approach to a class of dynamic image-based representations called "plenoptic videos," where the plenoptic video sequences are segmented into image-based rendering (IBR) objects each with its image sequence, depth map, and other relevant information such as shape and alpha information. This allows desirable functionalities such as scalability of contents, error resilience, and interactivity with individual IBR objects to be supported. Moreover, the rendering quality in scenes with large depth variations can also be improved considerably. A portable capturing system consisting of two linear camera arrays was developed to verify the proposed approach. An important step in the object-based approach is to segment the objects in video streams into layers or IBR objects. To reduce the time for segmenting plenoptic videos under the semiautomatic technique, a new object tracking method based on the level-set method is proposed. Due to possible segmentation errors around object boundaries, natural matting with Bayesian approach is also incorporated into our system. Furthermore, extensions of conventional image processing algorithms to these IBR objects are studied and illustrated with examples. Experimental results are given to illustrate the efficiency of the tracking, matting, rendering, and processing algorithms under the proposed object-based framework. © 2009 IEEE.published_or_final_versio

The Plenoptic videos: Capturing, Rendering and Compression

This paper presents a system for capturing and rendering a dynamic image-based representation called the plenoptic videos. It is a simplified version of light fields for dynamic environment, where user viewpoints are constrained along the camera plane of a linear array of video cameras. The system consists of a camera array of 8 Sony CCX-Z11 CCD cameras and eight Pentium 41.8 GHz computers connected together through a 100 baseT LAN. Important issues such as multiple camera calibration, real-time compression, decompression and rendering are addressed. Experimental results demonstrated the usefulness of the proposed parallel processing based system in capturing and rendering high quality dynamic image-based representation using off-the-shelf equipment, and its potential applications in visualization and immersive television systems.published_or_final_versio

Rapid and efficient generation of neural progenitors from adult bone marrow stromal cells by hypoxic preconditioning

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Talking Less during Social Interactions Predicts Enjoyment: A Mobile Sensing Pilot Study

Can we predict which conversations are enjoyable without hearing the words that are spoken? A total of 36 participants used a mobile app, My Social Ties, which collected data about 473 conversations that the participants engaged in as they went about their daily lives. We tested whether conversational properties (conversation length, rate of turn taking, proportion of speaking time) and acoustical properties (volume, pitch) could predict enjoyment of a conversation. Surprisingly, people enjoyed their conversations more when they spoke a smaller proportion of the time. This pilot study demonstrates how conversational properties of social interactions can predict psychologically meaningful outcomes, such as how much a person enjoys the conversation. It also illustrates how mobile phones can provide a window into everyday social experiences and well-being

Inter-rater reliability of three standardized functional tests in patients with low back pain

<p>Abstract</p> <p>Background</p> <p>Of all patients with low back pain, 85% are diagnosed as "non-specific lumbar pain". Lumbar instability has been described as one specific diagnosis which several authors have described as delayed muscular responses, impaired postural control as well as impaired muscular coordination among these patients. This has mostly been measured and evaluated in a laboratory setting. There are few standardized and evaluated functional tests, examining functional muscular coordination which are also applicable in the non-laboratory setting. In ordinary clinical work, tests of functional muscular coordination should be easy to apply. The aim of this present study was to therefore standardize and examine the inter-rater reliability of three functional tests of muscular functional coordination of the lumbar spine in patients with low back pain.</p> <p>Methods</p> <p>Nineteen consecutive individuals, ten men and nine women were included. (Mean age 42 years, SD ± 12 yrs). Two independent examiners assessed three tests: "single limb stance", "sitting on a Bobath ball with one leg lifted" and "unilateral pelvic lift" on the same occasion. The standardization procedure took altered positions of the spine or pelvis and compensatory movements of the free extremities into account. The inter-rater reliability was analyzed by Cohen's kappa coefficient (κ) and by percentage agreement.</p> <p>Results</p> <p>The inter-rater reliability for the right and the left leg respectively was: for the single limb stance very good (κ: 0.88–1.0), for sitting on a Bobath ball good (κ: 0.79) and very good (κ: 0.88) and for the unilateral pelvic lift: good (κ: 0.61) and moderate (κ: 0.47).</p> <p>Conclusion</p> <p>The present study showed good to very good inter-rater reliability for two standardized tests, that is, the single-limb stance and sitting on a Bobath-ball with one leg lifted. Inter-rater reliability for the unilateral pelvic lift test was moderate to good. Validation of the tests in their ability to evaluate lumbar stability is required.</p

Placental 11-Beta Hydroxysteroid Dehydrogenase Methylation Is Associated with Newborn Growth and a Measure of Neurobehavioral Outcome

Background: There is growing evidence that the intrauterine environment can impact the neurodevelopment of the fetus through alterations in the functional epigenome of the placenta. In the placenta, the HSD11B2 gene encoding the 11-beta hydroxysteroid dehydrogenase enzyme, which is responsible for the inactivation of maternal cortisol, is regulated by DNA methylation, and has been shown to be susceptible to stressors from the maternal environment. Methodology/Principal Findings: We examined the association between DNA methylation of the HSD11B2 promoter region in the placenta of 185 healthy newborn infants and infant and maternal characteristics, as well as the association between this epigenetic variability and newborn neurobehavioral outcome assessed with the NICU Network Neurobehavioral Scales. Controlling for confounders, HSD11B2 methylation extent is greatest in infants with the lowest birthweights (P = 0.04), and this increasing methylation was associated with reduced scores of quality of movement (P = 0.04). Conclusions/Significance: These results suggest that factors in the intrauterine environment which contribute to birth outcome may be associated with placental methylation of the HSD11B2 gene and that this epigenetic alteration is in turn associated with a prospectively predictive early neurobehavioral outcome, suggesting in some part a mechanism for th

Global Distribution of Outbreaks of Water-Associated Infectious Diseases

Water is essential for maintaining life on Earth but can also serve as a media for many pathogenic organisms, causing a high disease burden globally. However, how the global distribution of water-associated infectious pathogens/diseases looks like and how such distribution is related to possible social and environmental factors remain largely unknown. In this study, we compiled a database on distribution, biology, and epidemiology of water-associated infectious diseases and collected data on population density, annual accumulated temperature, surface water areas, average annual precipitation, and per capita GDP at the global scale. From the database we extracted reported outbreak events from 1991 to 2008 and developed models to explore the association between the distribution of these outbreaks and social and environmental factors. A total of1,428 outbreaks had been reported and this number only reflected ‘the tip of the iceberg’ of the much bigger problem. We found that the outbreaks of water-associated infectious diseases are significantly correlated with social and environmental factors and that all regions are affected disproportionately by different categories of diseases. Relative risk maps are generated to show ‘hotspots’ of risks for different diseases. Despite certain limitations, the findings may be instrumental for future studies and prioritizing health resources