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News about Linfield alumn

Feature Tracking Cardiac Magnetic Resonance via Deep Learning and Spline Optimization

Feature tracking Cardiac Magnetic Resonance (CMR) has recently emerged as an area of interest for quantification of regional cardiac function from balanced, steady state free precession (SSFP) cine sequences. However, currently available techniques lack full automation, limiting reproducibility. We propose a fully automated technique whereby a CMR image sequence is first segmented with a deep, fully convolutional neural network (CNN) architecture, and quadratic basis splines are fitted simultaneously across all cardiac frames using least squares optimization. Experiments are performed using data from 42 patients with hypertrophic cardiomyopathy (HCM) and 21 healthy control subjects. In terms of segmentation, we compared state-of-the-art CNN frameworks, U-Net and dilated convolution architectures, with and without temporal context, using cross validation with three folds. Performance relative to expert manual segmentation was similar across all networks: pixel accuracy was ~97%, intersection-over-union (IoU) across all classes was ~87%, and IoU across foreground classes only was ~85%. Endocardial left ventricular circumferential strain calculated from the proposed pipeline was significantly different in control and disease subjects (-25.3% vs -29.1%, p = 0.006), in agreement with the current clinical literature.Comment: Accepted to Functional Imaging and Modeling of the Heart (FIMH) 201

PERCUSSION AND VIBRATION AIRWAY CLEARANCE THERAPY INCREASES INFLAMMATORY FACTORS

Ventilator associated pneumonia is a common problem with the mechanically ventilated population. Mortality, hospital stay, and cost increase with ventilator associated pneumonia. The importance of tackling this problem has spurred an effort within the medical community to prevent the onset of VAP. Upon years of study, a basic bundle of care has been recommended by the IHI for implementation in the hospital so that the incidence of VAP would decrease. This paper will focus on the nurse’s role in implementing the bundle of care. The paper will explore the different interventions and will cover the evidence behind the practice. The paper will also try to mention the avenues in which research can focus due to the lack of development in that area.https://scholarscompass.vcu.edu/uresposters/1011/thumbnail.jp

Nutrition Education in Vermont Public Schools

Introduction. Despite positive changes, childhood obesity and food insecurity remain prevalent across the country. Vermont is not immune to these issues. We set out to: research the level of nutrition education Vermont elementary schools provide their students, understand teacher perceptions of these programs, and recommend ways to fill identified gaps. Methods. Our study is a cross-sectional survey of Vermont educators around nutrition education. The survey consisted of 17 questions, used LimeSurvey, and included demographic and nutrition education questions. The survey was distributed statewide through newsletters and list-servers. Results. 64 responses met inclusion criteria. Vermont elementary school (K-6) teachers report a mean satisfaction score of 2.51 out of 5.0 for their schools\u27 current nutrition education programs. School nurses reported a score of 2.5 out of 5.0. Highest satisfaction scores included school administrators and health and wellness coordinators (3.3 out of 5.0). When comparing teachers to non-classroom educators (administrators and nutrition educators) data showed a significant difference between high satisfaction (3-5) and low satisfaction (1-2); (Fischer p = 0.009). Overall, Vermont elementary school teachers report a high level of knowledge about nutrition, (4.1/5.0), but a lower level of understanding in their students (2.5/5.0). Conclusions. Given teacher perceptions regarding current school nutrition education programs, development and implementation of a state-wide nutrition education curriculum with dedicated teaching time may be warranted. Programs recommended by the CDC include Eat Well & Get Moving and Planet Health, designed by the Harvard School of Public Health. These could be adapted as a framework for Vermont.https://scholarworks.uvm.edu/comphp_gallery/1244/thumbnail.jp

Evidence of boosted 13CO/12CO ratio in early-type galaxies in dense environments

We present observations of $^{13}$CO(1-0) in 17 Combined Array for Research in Millimeter Astronomy (CARMA) Atlas3D early-type galaxies (ETGs), obtained simultaneously with $^{12}$CO(1-0) observations. The $^{13}$CO in six ETGs is sufficiently bright to create images. In these 6 sources, we do not detect any significant radial gradient in the $^{13}$CO/$^{12}$CO ratio between the nucleus and the outlying molecular gas. Using the $^{12}$CO channel maps as 3D masks to stack the $^{13}$CO emission, we are able to detect 15/17 galaxies to $>3\sigma$ (and 12/17 to at least 5$\sigma$) significance in a spatially integrated manner. Overall, ETGs show a wide distribution of $^{13}$CO/$^{12}$CO ratios, but Virgo cluster and group galaxies preferentially show a $^{13}$CO/$^{12}$CO ratio about 2 times larger than field galaxies, although this could also be due to a mass dependence, or the CO spatial extent ($R_{\rm CO}/R_{\rm e}$). ETGs whose gas has a morphologically-settled appearance also show boosted $^{13}$CO/$^{12}$CO ratios. We hypothesize that this variation could be caused by (i) the extra enrichment of gas from molecular reprocessing occurring in low-mass stars (boosting the abundance of $^{13}$C to $^{12}$C in the absence of external gas accretion), (ii) much higher pressure being exerted on the midplane gas (by the intracluster medium) in the cluster environment than in isolated galaxies, or (iii) all but the densest molecular gas clumps being stripped as the galaxies fall into the cluster. Further observations of $^{13}$CO in dense environments, particularly of spirals, as well as studies of other isotopologues, should be able to distinguish between these hypotheses.Comment: 13 pages, 3 tables, 7 figures, accepted by MNRA

AEGIS: Chandra Observation of DEEP2 Galaxy Groups and Clusters

We present a 200 ksec Chandra observation of seven spectroscopically selected, high redshift (0.75 < z < 1.03) galaxy groups and clusters discovered by the DEEP2 Galaxy Redshift Survey in the Extended Groth Strip (EGS). X-ray emission at the locations of these systems is consistent with background. The 3-sigma upper limits on the bolometric X-ray luminosities (L_X) of these systems put a strong constraint on the relation between L_X and the velocity dispersion of member galaxies sigma_gal at z~1; the DEEP2 systems have lower luminosity than would be predicted by the local relation. Our result is consistent with recent findings that at high redshift, optically selected clusters tend to be X-ray underluminous. A comparison with mock catalogs indicates that it is unlikely that this effect is entirely caused by a measurement bias between sigma_gal and the dark matter velocity dispersion. Physically, the DEEP2 systems may still be in the process of forming and hence not fully virialized, or they may be deficient in hot gas compared to local systems. We find only one possibly extended source in this Chandra field, which happens to lie outside the DEEP2 coverage.Comment: 5 pages, 3 figures. Accepted for publication in AEGIS ApJ Letters special editio

Characterisation of the Mycobacterium tuberculosis alternative sigma factor SigG: its operon and regulon.

A major step in the pathogenesis of Mycobacterium tuberculosis is the ability to survive inside macrophages, where it is exposed to a number of DNA damaging agents. The alternative sigma factor SigG has been shown to be upregulated by DNA damaging agents and by macrophage infection, but not to regulate genes of the DNA repair pathway. Here we show that SigG is expressed from at least two promoters, the most dominant of these being the DNA damage inducible RecA_Ndp promoter. This promoter is located within the annotated coding region of SigG and so the correct translational start site was determined experimentally and found to be 114 bp downstream of the annotated start site. Examining the gene expression profile of a SigG over-expression strain found a small number of genes to up-regulated, two of these encoded proteins containing glyoxylase-like domains