Kassin S.A.,Goddard Space Flight Center |
Devriendt J.,University of Oxford |
Fall S.M.,US Space Telescope Science Institute |
de Jong R.S.,Leibniz Institute for Astrophysics Potsdam |
And 3 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2012
In the standard picture of disc galaxy formation, baryons and dark matter receive the same tidal torques, and therefore approximately the same initial specific angular momentum. However, observations indicate that disc galaxies typically have only about half as much specific angular momentum as their dark matter haloes. We argue this does not necessarily imply that baryons lose this much specific angular momentum as they form galaxies. It may instead indicate that galaxies are most directly related to the inner regions of their host haloes, as may be expected in a scenario where baryons in the inner parts of haloes collapse first. A limiting case is examined under the idealized assumption of perfect angular momentum conservation. Namely, we determine the density contrast Δ, with respect to the critical density of the Universe, by which dark matter haloes need to be defined in order to have the same average specific angular momentum as the galaxies they host. Under the assumption that galaxies are related to haloes via their characteristic rotation velocities, the necessary Δ is ∼600. This Δ corresponds to an average halo radius and mass which are ∼60per cent and ∼75per cent, respectively, of the virial values (i.e. for Δ= 200). We refer to this radius as the radius of baryonic collapse R BC, since if specific angular momentum is conserved perfectly, baryons would come from within it. It is not likely a simple step function due to the complex gastrophysics involved; therefore, we regard it as an effective radius. In summary, the difference between the predicted initial and the observed final specific angular momentum of galaxies, which is conventionally attributed solely to angular momentum loss, can more naturally be explained by a preference for collapse of baryons within R BC, with possibly some later angular momentum transfer. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS. Source
Numerate | Date: 2015-05-28
A system, method, and computer program product are provided for identifying a first markup document including first numerical values and first tags reflecting first characteristics of the first numerical values associated with a first unit of measure, and a second markup document including second numerical values and second tags reflecting second characteristics of the second numerical values associated with a second unit of measure. The first characteristics of the first numerical values associated with the first unit of measure are different from the second characteristics of the second numerical values associated with the second unit of measure. At least a portion of the numerical values of at least one of the first markup document or the second markup document are automatically transformed, so that the at least some of the first numerical values of the first markup document and at least some of the second numerical values of the second markup document have a common unit of measure. Further, at least a part of the first markup document and at least a part of the second markup document are processed, resulting in a single markup document, for display.
Numerate | Date: 2012-03-06
Methods and articles of manufacture for modeling molecular properties using data regarding the partial orderings of compound properties, or by considering measurements of compound properties in terms of partial orderings are disclosed. One embodiment provides for constructing such partial orderings from data that is not already in an ordered form by processing training data to produce a partial ordering of the compounds with respect to a property of interest. Another embodiment of the invention may process the modified training data to construct a model that predicts the property of interest for arbitrary compounds.
Agency: Department of Health and Human Services | Branch: | Program: STTR | Phase: Phase I | Award Amount: 203.69K | Year: 2009
DESCRIPTION (provided by applicant): The objective of this project is to design and develop a locally acting, allosteric inhibitor of the enzyme transglutaminase 2 (TG2). TG2 activity is central to the pathogenesis of celiac sprue, a gluten induced autoimmune disease of the small intestine for which no pharmacotherapy exists. Toward this end two specific aims are proposed in this application: 1) Characterize TG2 inhibitors using a non-denaturing polyacrylamide gel electrophoresis (PAGE) assay which distinguishes the closed, inactivated conformation of TG2 from the open, activated form. These studies are designed to distinguish allosteric inhibitors of the inactivated state from active site inhibitors. 2) Design, synthesize and assay new allosteric inhibitors which have been engineered for improved potency. This research is intended to identify one or more lead series for optimization in subsequent work. Initial work will involve testing TG2 inhibitors identified in Preliminary Studies with the non-denaturing PAGE assay. The results of these experiments will be used to refine a predictive in silico model for allosteric TG2 inhibitors. Next, a large and diverse virtual library of potential allosteric TG2 inhibitors will be defined, encompassing approximately 3B compounds. Compounds from this space will be sampled and optimized using a closed-loop engineering process in which the predictive model for TG2 inhibitors will serve as the primary objective function. A small set (6-9) of the most promising engineered inhibitors will be synthesized and characterized in biochemical, cellular and conformational assays of TG2 inhibition. The projected outcome of these experiments is to identify and qualify a lead series for further optimization. PUBLIC HEALTH RELEVANCE: This research involves the design of a medicine to treat celiac sprue, an autoimmune disease of the small intestine. No therapeutic agent is currently available to treat celiac sprue, which afflicts 0.5-1% of the population.
Numerate | Date: 2015-05-28
A system, method, and computer program product are provided for use in connection with at least one computer-readable Extensible Markup Language (XML)-compliant data document capable of including: a plurality of line items with a plurality of data values, and a plurality of computer-readable semantic tags that describe a semantic meaning of the data values.