DBI Realizations of the Pseudo-Conformal Universe and Galilean Genesis Scenarios

The pseudo-conformal universe is an alternative to inflation in which the early universe is described by a conformal field theory on approximately flat space-time. The fields develop time-dependent expectation values, spontaneously breaking the conformal symmetries to a de Sitter subalgebra, and fields of conformal weight zero acquire a scale invariant spectrum of perturbations. In this paper, we show that the pseudo-conformal scenario can be naturally realized within theories that would ordinarily be of interest for DBI inflation, such as the world-volume theory of a probe brane in an AdS bulk space-time. In this approach, the weight zero spectator field can be associated with a geometric flat direction in the bulk, and its scale invariance is protected by a shift symmetry.Comment: 34 page

Rats on the Rocks: Does Intermittent Stress Exposure During Adolescence Lead to Increases in Alcohol Drinking?

Finalist for Awar

Emotion Knowledge, Loneliness, Negative Social Experiences, and Internalizing Symptoms Among Low‐income Preschoolers

Children with poor emotion knowledge (EK) skills are at risk for externalizing problems; less is known about early internalizing behavior. We examined multiple facets of EK and social‐emotional experiences relevant for internalizing difficulties, including loneliness, victimization, and peer rejection, in Head Start preschoolers (N = 134; M = 60 months). Results based on multiple informants suggest that facets of EK are differentially related to negative social‐emotional experiences and internalizing behavior and that sex plays a moderating role. Behavioral EK was associated with self‐reported loneliness, victimization/rejection, and parent‐reported internalizing symptoms. Emotion recognition and expressive EK were related to self‐reported loneliness, and emotion situation knowledge was related to parent‐reported internalizing symptoms and negative peer nominations. Sex moderated many of these associations, suggesting that EK may operate differently for girls vs. boys in the preschool social context. Results are discussed with regard to the role of EK for social development and intervention implications.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110878/1/sode12083.pd

Can the Desiccation of Great Salt Lake be Stopped?

Great Salt Lake is a terminal lake, with its watershed in the Wasatch and Uinta Mountains of Utah, Wyoming and Idaho. Like all terminal lakes, the water inflows are balanced only by evaporative loss from its surface—when inflows decrease the lake shrinks until evaporation matches that inflow

A Retrospective Study at Two Level One Trauma Centers on the Association of Internal Injuries with Femoral Fractures

Abstract: Injuries capable of fracturing the femur often involve concurrent internal organ damage. However, up to 25% of injuries are initially missed. Prior studies evaluating the association of femur fractures with internal injury included only automobile trauma, were skewed toward more severe injuries, and were broad database studies. To our knowledge, there are no studies of this kind that include bicycle, motorcycle, and motor vehicle-pedestrian trauma, excluding those deceased at the scene, and which included chart reviews. We hypothesized that in the trauma setting, the presence of a femur fracture would correlate with an increase in concomitant internal organ injuries. Data was retrospectively queried from two Level I Trauma Centers. Patients presenting between January 1, 2005 and December 31, 2012 with trauma activation met inclusion criteria. Patients were stratified based on presence of a femur fracture, open/closed fracture status, and shaft versus non-shaft fractures. Internal organ injuries were documented. Logistic regression analysis was used to determine if the presence of a femur fracture, open fractures, or shaft fractures were predictive of internal injuries. Results were reported as odds ratios with 95% confidence intervals (CI). A p-value \u3c 0.05 was statistically significant. Femur fracture and open fracture were associated with additional internal injury. Shaft fractures were not associated with additional injury. Subjects ≤18 years with femur fracture were more likely to sustain additional injury compared to older age groups. The current study reveals that fractures of the femur in this setting may be associated with additional internal injuries. Open fractures may portend more severe organ injury compared to closed fractures. Femoral fracture in age ≥65 may not be as predictive for associated internal injuries. Development of a standardized grading system may aid in alerting the provider to the potential for these life-threatening injuries. Level of evidence: IV

Two Inter-Row Spacing and Staggered Planting on Collard (Brassica oleracea L. var. acephala DC.) Yield in a Wiregrass Tunnel House

There is interest among small vegetable producers to grow collards in Tunnel Houses during the winter months. Consequently, the purpose of this study was to determine if collard yields could be increased by reducing row spacing and increasing plant density. This study had four treatments replicated three times, and “Georgia” and “Hi-Crop Hybrid” collards were transplanted on single, and staggered rows spaced 18” and 24” apart in a split-split-plot design. At 45 days after transplanting 50% of the leaves from all plants in each treatment were harvested, counted, and weighed. The results showed staggered 18 and 24” rows increased yields by 43 and 51%, respectively, over single planted rows for both varieties. Staggered rows incurred higher planting costs, but increased net returns to management. The increase in yield was variety-dependent, thus suggesting that the genetic potential of the varieties needs to be considered when using plant density to increase yields

Targeted Neural Dynamical Modeling

Latent dynamics models have emerged as powerful tools for modeling and interpreting neural population activity. Recently, there has been a focus on incorporating simultaneously measured behaviour into these models to further disentangle sources of neural variability in their latent space. These approaches, however, are limited in their ability to capture the underlying neural dynamics (e.g. linear) and in their ability to relate the learned dynamics back to the observed behaviour (e.g. no time lag). To this end, we introduce Targeted Neural Dynamical Modeling (TNDM), a nonlinear state-space model that jointly models the neural activity and external behavioural variables. TNDM decomposes neural dynamics into behaviourally relevant and behaviourally irrelevant dynamics; the relevant dynamics are used to reconstruct the behaviour through a flexible linear decoder and both sets of dynamics are used to reconstruct the neural activity through a linear decoder with no time lag. We implement TNDM as a sequential variational autoencoder and validate it on simulated recordings and recordings taken from the premotor and motor cortex of a monkey performing a center-out reaching task. We show that TNDM is able to learn low-dimensional latent dynamics that are highly predictive of behaviour without sacrificing its fit to the neural data