65 research outputs found
Research Partnerships: Undertaking and Understanding Collaborative Ethnography in Indianapolis
poster abstractStudents will present a range of collaborative research projects they have undertaken in consultation with neighborhood and community-based organizations in Indianapolis. They will address the benefits, challenges and limitations that collaborative research has posed for them, as ethnographers-in-trainin
Laser Positioning System
System for positioning a laser deflector around the head for maxillofacial surgery
p70S6 Kinase Phosphorylates AMPK on Serine 491 to Mediate Leptin's Effect on Food Intake
SummaryThe PI3K-AKT, mTOR-p70S6 kinase and AMPK pathways play distinct and critical roles in metabolic regulation. Each pathway is necessary for leptin's anorexigenic effects in the hypothalamus. Here we show that these pathways converge in an integrated phosphorylation cascade to mediate leptin action in the hypothalamus. We identify serine491 on α2AMPK as the site of convergence and show that p70S6 kinase forms a complex with α2AMPK, resulting in phosphorylation on serine491. Blocking α2AMPK-serine491 phosphorylation increases hypothalamic AMPK activity, food intake, and body weight. Serine491 phosphorylation is necessary for leptin's effects on hypothalamic α2AMPK activity, neuropeptide expression, food intake, and body weight. These results identify an inhibitory AMPK kinase, p70S6 kinase, and demonstrate that AMPK is a substrate for mTOR-p70S6 kinase. This discovery has broad biologic implications since mTOR-p70S6 kinase and AMPK have multiple, fundamental and generally opposing cellular effects that regulate metabolism, cell growth, and development
Astrophysical Fluid Dynamics via Direct Statistical Simulation
In this paper we introduce the concept of Direct Statistical Simulation (DSS)
for astrophysical flows. This technique may be appropriate for problems in
astrophysical fluids where the instantaneous dynamics of the flows are of
secondary importance to their statistical properties. We give examples of such
problems including mixing and transport in planets, stars and disks. The method
is described for a general set of evolution equations, before we consider the
specific case of a spectral method optimised for problems on a spherical
surface. The method is illustrated for the simplest non-trivial example of
hydrodynamics and MHD on a rotating spherical surface. We then discuss possible
extensions of the method both in terms of computational methods and the range
of astrophysical problems that are of interest.Comment: 26 pages, 11 figures, added clarifying remarks and references, and
corrected typos. This version is accepted for publication in The
Astrophysical Journa
DNA Dynamics Is Likely to Be a Factor in the Genomic Nucleotide Repeats Expansions Related to Diseases
Trinucleotide repeats sequences (TRS) represent a common type of genomic DNA
motif whose expansion is associated with a large number of human diseases. The
driving molecular mechanisms of the TRS ongoing dynamic expansion across
generations and within tissues and its influence on genomic DNA functions are
not well understood. Here we report results for a novel and notable collective
breathing behavior of genomic DNA of tandem TRS, leading to propensity for large
local DNA transient openings at physiological temperature. Our Langevin
molecular dynamics (LMD) and Markov Chain Monte Carlo (MCMC) simulations
demonstrate that the patterns of openings of various TRSs depend specifically on
their length. The collective propensity for DNA strand separation of repeated
sequences serves as a precursor for outsized intermediate bubble states
independently of the G/C-content. We report that repeats have the potential to
interfere with the binding of transcription factors to their consensus sequence
by altered DNA breathing dynamics in proximity of the binding sites. These
observations might influence ongoing attempts to use LMD and MCMC simulations
for TRS–related modeling of genomic DNA functionality in elucidating the
common denominators of the dynamic TRS expansion mutation with potential
therapeutic applications
Porte-outils semi-actif pour la pose de vis transarticulaires
Ce poster décrit le porte-outils développé par le VRAI Group pour l'assistance à la pose de vis transarticulaires dans les vertèbres C1/C2
Recalage rigide sans contact d'une vertèbre
Le but de ce travail est d'évaluer la possibilité d'effectuer le recalage rigide de la vertèbre d'un patient avec son modèle virtuelle en se basant sur des images échographiques 3D
Etablissement du squelette d'un modèle virtuel tridimensionnel
Ce travail s'inscrit dans le cadre d'un projet de recherche consistant à développer une technique rapide de mise à jour de la planification préopératoire de résection hépatique en salle d'opération. Le but de ce travail est d'établir et implémenter un algorithme permettant d'extraire automatiquement le squelette du réseau vasculaire
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