Embedding spheres in knot traces

The trace of the n-framed surgery on a knot in S3 is a 4-manifold homotopy equivalent to the 2-sphere. We characterise when a generator of the second homotopy group of such a manifold can be realised by a locally flat embedded 2-sphere whose complement has abelian fundamental group. Our characterisation is in terms of classical and computable 3-dimensional knot invariants. For each n, this provides conditions that imply a knot is topologically n-shake slice, directly analogous to the result of Freedman and Quinn that a knot with trivial Alexander polynomial is topologically slice

Confronting Standard Models of Proto--Planetary Disks With New Mid--Infrared Sizes from the Keck Interferometer

We present near and mid-infrared interferometric observations made with the Keck Interferometer Nuller and near-contemporaneous spectro-photometry from the IRTF of 11 well known young stellar objects, several observed for the first time in these spectral and spatial resolution regimes. With AU-level spatial resolution, we first establish characteristic sizes of the infrared emission using a simple geometrical model consisting of a hot inner rim and mid-infrared disk emission. We find a high degree of correlation between the stellar luminosity and the mid-infrared disk sizes after using near-infrared data to remove the contribution from the inner rim. We then use a semi-analytical physical model to also find that the very widely used "star + inner dust rim + flared disk" class of models strongly fails to reproduce the SED and spatially-resolved mid-infrared data simultaneously; specifically a more compact source of mid-infrared emission is required than results from the standard flared disk model. We explore the viability of a modification to the model whereby a second dust rim containing smaller dust grains is added, and find that the two-rim model leads to significantly improved fits in most cases. This complexity is largely missed when carrying out SED modelling alone, although detailed silicate feature fitting by McClure et al. 2013 recently came to a similar conclusion. As has been suggested recently by Menu et al. 2015, the difficulty in predicting mid-infrared sizes from the SED alone might hint at "transition disk"-like gaps in the inner AU; however, the relatively high correlation found in our mid-infrared disk size vs. stellar luminosity relation favors layered disk morphologies and points to missing disk model ingredients instead

MINMOD Millennium: A Computer Program to Calculate Glucose Effectiveness and Insulin Sensitivity From the Frequently Sampled Intravenous Glucose Tolerance Test

The Bergman Minimal Model enables estimation of two key indices of glucose/insulin dynamics: glucose effectiveness and insulin sensitivity. In this paper we describe MINMOD Millennium, the latest Windows-based version of minimal model software. Extensive beta testing of MINMOD Millennium has shown that it is user-friendly, fully automatic, fast, accurate, reproducible, repeatable, and highly concordant with past versions of MINMOD. It has a simple interface, a comprehensive help system, an input file editor, a file converter, an intelligent processing kernel, and a file exporter. It provides publication-quality charts of glucose and insulin and a table of all minimal model parameters and their error estimates. In contrast to earlier versions of MINMOD and some other minimal model programs, Millennium provides identified estimates of insulin sensitivity and glucose effectiveness for almost every subject

Transposable element evolution in Heliconius suggests genome diversity within Lepidoptera

Background Transposable elements (TEs) have the potential to impact genome structure, function and evolution in profound ways. In order to understand the contribution of transposable elements (TEs) to Heliconius melpomene, we queried the H. melpomene draft sequence to identify repetitive sequences. Results We determined that TEs comprise ~25% of the genome. The predominant class of TEs (~12% of the genome) was the non-long terminal repeat (non-LTR) retrotransposons, including a novel SINE family. However, this was only slightly higher than content derived from DNA transposons, which are diverse, with several families having mobilized in the recent past. Compared to the only other well-studied lepidopteran genome, Bombyx mori, H. melpomene exhibits a higher DNA transposon content and a distinct repertoire of retrotransposons. We also found that H. melpomene exhibits a high rate of TE turnover with few older elements accumulating in the genome. Conclusions Our analysis represents the first complete, de novo characterization of TE content in a butterfly genome and suggests that, while TEs are able to invade and multiply, TEs have an overall deleterious effect and/or that maintaining a small genome is advantageous. Our results also hint that analysis of additional lepidopteran genomes will reveal substantial TE diversity within the group

The development of emotion regulation: an fMRI study of cognitive reappraisal in children, adolescents and young adults

The ability to use cognitive reappraisal to regulate emotions is an adaptive skill in adulthood, but little is known about its development. Because reappraisal is thought to be supported by linearly developing prefrontal regions, one prediction is that reappraisal ability develops linearly. However, recent investigations into socio-emotional development suggest that there are non-linear patterns that uniquely affect adolescents. We compared older children (10–13), adolescents (14–17) and young adults (18–22) on a task that distinguishes negative emotional reactivity from reappraisal ability. Behaviorally, we observed no age differences in self-reported emotional reactivity, but linear and quadratic relationships between reappraisal ability and age. Neurally, we observed linear age-related increases in activation in the left ventrolateral prefrontal cortex, previously identified in adult reappraisal. We observed a quadratic pattern of activation with age in regions associated with social cognitive processes like mental state attribution (medial prefrontal cortex, posterior cingulate cortex, anterior temporal cortex). In these regions, we observed relatively lower reactivity-related activation in adolescents, but higher reappraisal-related activation. This suggests that (i) engagement of the cognitive control components of reappraisal increases linearly with age and (ii) adolescents may not normally recruit regions associated with mental state attribution, but (iii) this can be reversed with reappraisal instructions.National Science Foundation (U.S.) (Grant BCS-0224342

Amyloid hydrogen bonding polymorphism evaluated by15N{17O}REAPDOR solid-state NMR and ultra-high resolution fourier transform ion cyclotron resonance mass spectrometry

A combined approach, using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and solid-state NMR (Nuclear Magnetic Resonance), shows a high degree of polymorphism exhibited by Aβ species in forming hydrogen-bonded networks. Two Alzheimer’s Aβ peptides, Ac-Aβ16–22-NH2 and Aβ11–25, selectively labeled with 17O and 15N at specific amino acid residues were investigated. The total amount of peptides labeled with 17O as measured by FTICR-MS enabled the interpretation of dephasing observed in 15N{17O}REAPDOR solid-state NMR experiments. Specifically, about one-third of the Aβ peptides were found to be involved in the formation of a specific >C═17O···H–15N hydrogen bond with their neighbor peptide molecules, and we hypothesize that the rest of the molecules undergo ± n off-registry shifts in their hydrogen bonding networks

Confronting standard models of proto-planetary disks with new mid-infrared sizes from the Keck Interferometer

This is the author accepted manuscript. The final version is available from American Astronomical Society/IOP Publishing via the DOI in this record.The published version is in ORE at http://hdl.handle.net/10871/30943We present near and mid–infrared interferometric observations made with the Keck Interferometer Nuller and near–contemporaneous spectro–photometry from the IRTF of 11 well known young stellar objects, several observed for the first time in these spectral and spatial resolution regimes. With AU–level spatial resolution, we first establish characteristic sizes of the infrared emission using a simple geometrical model consisting of a hot inner rim and mid–infrared disk emission. We find a high degree of correlation between the stellar luminosity and the mid–infrared disk sizes after using near–infrared data to remove the contribution from the inner rim. We then use a semi–analytical physical model to also find that the very widely used “star + inner dust rim+ flared disk” class of models strongly fails to reproduce the SED and spatially–resolved mid–infrared data simultaneously; specifically a more compact source of mid–infrared emission is required than results from the standard flared disk model. We explore the viability of a modification to the model whereby a second dust rim containing smaller dust grains is added, and find that the two–rim model leads to significantly improved fits in most cases. This complexity is largely missed when carrying out SED modelling alone, although detailed silicate feature fitting by McClure et al. (2013) recently came to a similar conclusion. As has been suggested recently by Menu et al. (2015), the difficulty in predicting mid–infrared sizes from the SED alone might hint at “transition disk”–like gaps in the inner AU; however, the relatively high correlation found in our mid–infrared disk size vs. stellar luminosity relation favors layered disk morphologies and points to missing disk model ingredients instead.The authors wish to acknowledge fruitful discussions with Nuria Calvet and Melissa McClure. Part of this work was performed while X. C. was a Visiting Graduate Student Research Fellow at the Infrared Processing and Analysis Center (IPAC), California Institute of Technology. The Keck Interferometer was funded by the National Aeronautics and Space Administration as part of its Exoplanet Exploration Program. Data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. Data presented in this paper were obtained at the Infrared Telescope Facility, which is operated by the University of Hawaii under contract NNH14CK55B with the National Aeronautics and Space Administration. We gratefully acknowledge support and participation in the IRTF/BASS observing runs by Daryl Kim, The Aerospace Corporation. This work has made use of services produced by the NASA Exoplanet Science Institute at the California Institute of Technology. M. S. was supported by NASA ADAP grant NNX09AC73G. R. W. R. was supported by the IR&D program of The Aerospace Corporatio