Multi-Pose Fusion for Sparse-View CT Reconstruction Using Consensus Equilibrium

CT imaging works by reconstructing an object of interest from a collection of projections. Traditional methods such as filtered-back projection (FBP) work on projection images acquired around a fixed rotation axis. However, for some CT problems, it is desirable to perform a joint reconstruction from projection data acquired from multiple rotation axes. In this paper, we present Multi-Pose Fusion, a novel algorithm that performs a joint tomographic reconstruction from CT scans acquired from multiple poses of a single object, where each pose has a distinct rotation axis. Our approach uses multi-agent consensus equilibrium (MACE), an extension of plug-and-play, as a framework for integrating projection data from different poses. We apply our method on simulated data and demonstrate that Multi-Pose Fusion can achieve a better reconstruction result than single pose reconstruction.Comment: To appear in 58th Annual Allerton Conference on Communication, Control, and Computin

4D X-Ray CT Reconstruction using Multi-Slice Fusion

There is an increasing need to reconstruct objects in four or more dimensions corresponding to space, time and other independent parameters. The best 4D reconstruction algorithms use regularized iterative reconstruction approaches such as model based iterative reconstruction (MBIR), which depends critically on the quality of the prior modeling. Recently, Plug-and-Play methods have been shown to be an effective way to incorporate advanced prior models using state-of-the-art denoising algorithms designed to remove additive white Gaussian noise (AWGN). However, state-of-the-art denoising algorithms such as BM4D and deep convolutional neural networks (CNNs) are primarily available for 2D and sometimes 3D images. In particular, CNNs are difficult and computationally expensive to implement in four or more dimensions, and training may be impossible if there is no associated high-dimensional training data. In this paper, we present Multi-Slice Fusion, a novel algorithm for 4D and higher-dimensional reconstruction, based on the fusion of multiple low-dimensional denoisers. Our approach uses multi-agent consensus equilibrium (MACE), an extension of Plug-and-Play, as a framework for integrating the multiple lower-dimensional prior models. We apply our method to the problem of 4D cone-beam X-ray CT reconstruction for Non Destructive Evaluation (NDE) of moving parts. This is done by solving the MACE equations using lower-dimensional CNN denoisers implemented in parallel on a heterogeneous cluster. Results on experimental CT data demonstrate that Multi-Slice Fusion can substantially improve the quality of reconstructions relative to traditional 4D priors, while also being practical to implement and train.Comment: 8 pages, 8 figures, IEEE International Conference on Computational Photography 2019, Toky

Tackling Concussion in Professional Rugby Union: A Case-Control Study of Tackle-Based Risk Factors and Recommendations for Primary Prevention

Background/aim Concussion, the most common injury in professional rugby union, occurs most commonly during the tackle. Thus, we investigated the association between tackle characteristics and concussion. Methods 182 video clips of tackles leading to clinically diagnosed concussion and 4619 tackles that did not were coded across three professional rugby union competitions. A variable selection process was undertaken to identify the most important variables for interpretation. A multivariate generalised linear model was used to model the association between retained variables and concussion risk. Magnitude-based inferences provided an interpretation of the real-world relevance of the outcomes. Results The four retained variables were: accelerating player, tackler speed, head contact type and tackle type. Overall, 70% of concussions occurred to the tackler and 30% to the ball carrier. There was a higher risk of concussion if the tackler accelerated into the tackle (OR: 2.49, 95% CI 1.70 to 3.64) or the tackler was moving at high speed (OR: 2.64, 95% CI 1.92 to 3.63). Head contact with the opposing player's head (OR: 39.9, 95% CI 22.2 to 71.1) resulted in a substantially greater risk of concussion compared with all other head contact locations. Conclusions Interventions that reduce the speed and acceleration of the tackler and reduce exposure to head-to-head contact would likely reduce concussion risk in professional rugby union.</p

Sodium bicarbonate ingestion and individual variability in time to peak pH

The aim of this study was to determine the individual variability in time to peak pH after the consumption of a 300mg.kg-1 dose of sodium bicarbonate (NaHCO3). Seventeen active males volunteered to participate in the study (mean ± SD: age 21.38 ± 1.5y; mass 75.8 ± 5.8kg; height 176.8 ± 7.6cm). Participants reported to the laboratory where a resting capillary blood sample was taken aseptically from the fingertip. After this, 300 mg.kg-1 of NaHCO3 in 400ml of water with 50ml of flavoured cordial was ingested. Participants then rested for 90 min during which repeated blood samples were procured at 10 minute intervals for 60 mins and then every 5 min until 90 min. Blood pH concentrations were measured using a blood gas analyser. Results suggested that time to peak pH (64.41±18.78 min) was highly variable with a range of 10-85 min and a coefficient of variation of 29.16%. A bi-modal distribution occurred, at 65 and 75 min. In conclusion, researchers and athletes, when using NaHCO3 as an ergogenic aid, should determine, in advance their time to peak pH to best utilise the added buffering capacity this substance allows

Internet-based medical education: a realist review of what works, for whom and in what circumstances

http://creativecommons.org/licenses/by/2.0

The Suppressor of AAC2 Lethality SAL1 Modulates Sensitivity of Heterologously Expressed Artemia ADP/ATP Carrier to Bongkrekate in Yeast

The ADP/ATP carrier protein (AAC) expressed in Artemia franciscana is refractory to bongkrekate. We generated two strains of Saccharomyces cerevisiae where AAC1 and AAC3 were inactivated and the AAC2 isoform was replaced with Artemia AAC containing a hemagglutinin tag (ArAAC-HA). In one of the strains the suppressor of ΔAAC2 lethality, SAL1, was also inactivated but a plasmid coding for yeast AAC2 was included, because the ArAACΔsal1Δ strain was lethal. In both strains ArAAC-HA was expressed and correctly localized to the mitochondria. Peptide sequencing of ArAAC expressed in Artemia and that expressed in the modified yeasts revealed identical amino acid sequences. The isolated mitochondria from both modified strains developed 85% of the membrane potential attained by mitochondria of control strains, and addition of ADP yielded bongkrekate-sensitive depolarizations implying acquired sensitivity of ArAAC-mediated adenine nucleotide exchange to this poison, independent from SAL1. However, growth of ArAAC-expressing yeasts in glycerol-containing media was arrested by bongkrekate only in the presence of SAL1. We conclude that the mitochondrial environment of yeasts relying on respiratory growth conferred sensitivity of ArAAC to bongkrekate in a SAL1-dependent manner. © 2013 Wysocka-Kapcinska et al

Inverse chemical modeling and radiocarbon dating of palaeogroundwaters: The Tertiairy Ledo-paniselian aquifer in Flanders, Belgium.

Groundwater samples from the Ledo-Paniselian aquifer have been interpreted for chemical reaction patterns

Stability in Bullying and Victimization and its Association with Social Adjustment in Childhood and Adolescence

This study examined the concurrent and longitudinal associations between stability in bullying and victimization, and social adjustment in childhood and adolescence. Participants were 189 girls and 328 boys who were studied in primary school and in secondary school. The mean age of the participants was 11.1 years in primary school and 14.1 years in secondary school. The measures consisted of peer reported social and personal characteristics. Children who bullied in childhood and adolescence were less liked and more disliked in childhood, and more aggressive and disruptive both in childhood and adolescence, than children who bullied only in childhood or adolescence. Children who bullied or who were victimized only in childhood did not differ largely in adolescence from the children that were never bullies or victims. Children who were victimized in adolescence closely resembled those who were victimized in childhood and adolescence in terms of being liked or disliked, being nominated as a friend, and shyness. The study stresses the need to distinguish between stable and transient bullies and victims