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Incremental Structure-Mapping
Many cognitive tasks involving analogy, such as understanding metaphors, problem-solving, and learning, require the ability to extend mappings as new information is found. This paper describes a new version of SME, called I-SME, that operates incrementally. I-SME is inspired by Keane's lAM model and the use of incremental mapping in Falkenhainer's PHINEAS learning system. W e describe the I-SME algorithm and discuss tradeoffs introduced by incremental mapping, including parallel versus serial pnxessing and pragmatic influences. The utility of 1-SME is illustrated by two examples. First, we show that I-SME can account for the psychological results found by Keane on a serial version of the Holyoak & Thagard attribute mapping task. Second, we describe how I-SME is used in the Minimal Analogical Reasoning System (MARS), which uses analogy to solve engineering thermodynamics problems
Qualitative Spatial Interpretation of Course-of-Action Diagrams
Abstract This paper demonstrates qualitative spatial reasonin g techniques in a real-world diagrammatic reasoning task: Course-of-Action (COA) diagrams . COA diagrams are military planning diagrams that depict unit movements an d tasks in a given region . COA diagrams are a useful test be d for researching diagram understanding due to their composable symbology, their intrinsically spatial task, an d their use across many types of military planning . W e constructed two COA diagram interpreters using ou r qualitative spatial reasoning engine, GeoRep . The firs t system uses GeoRep to interpret individual COA glyphs . The second system, building upon the first, takes preclassified symbol input and then uses GeoRep to describ e geographic relationships implied by the symbol arrangements . This latter system, in a recent DARPA initiative , answered dozens of geographic queries about many different COA diagrams . This research shows that qualitative spatial reasoning, through tools like GeoRep, provides a useful substrate for complex diagrammatic reasoning
The Opacity of Nearby Galaxies from Colors and Counts of Background Galaxies: I. The Synthetic Field Method and its Application to NGC 4536 and NGC 3664
We describe a new, direct method for determining the opacity of foreground
galaxies which does not require any a priori assumptions about the spatial
distribution or the reddening law of the obscuring material. The method is to
measure the colors and counts of background galaxies which can be identified
through the foreground system. The method is calibrated, and the effects of
confusion and obscuration are decoupled by adding various versions of a
suitable deep reference frame containing only field galaxies with known
properties into the image of the foreground galaxy, and analyzing these
``synthetic field'' images in the same way as the real images. We test the
method on HST WFPC2 archived images of two galaxies which are quite different:
NGC 4536 is a large Sc spiral, and NGC 3664 is a small Magellanic irregular.
The reference frames are taken from the Hubble Deep Field.
From the background galaxy counts, NGC 4536 shows an extinction A_I ~ 1 mag
in the northwestern arm region, and lower than 0.5 mag in the corresponding
interarm region (no correction for inclination has been attempted). However,
from the galaxy colors, the same reddening of E(V - I) ~ 0.2 is observed in
both the arm and the interarm regions. In the interarm region, the combination
of extinction and reddening can be explained by a diffuse component with a
Galactic reddening law (R_V ~ 3). In the spiral arm, however, the same diffuse,
low opacity component seems to coexist with regions of much higher opacity.
Since the exposures are shorter the results for NGC 3664 are less clear, but
also appear to be consistent with a two component distribution.Comment: 42 pages, 18 figures; accepted for publication in The Astrophysical
Journal, Vol. 506, October 10, 199
The Empirical Foundations of Telemedicine Interventions for Chronic Disease Management
The telemedicine intervention in chronic disease management promises to involve patients in their own care, provides continuous monitoring by their healthcare providers, identifies early symptoms, and responds promptly to exacerbations in their illnesses. This review set out to establish the evidence from the available literature on the impact of telemedicine for the management of three chronic diseases: congestive heart failure, stroke, and chronic obstructive pulmonary disease. By design, the review focuses on a limited set of representative chronic diseases because of their current and increasing importance relative to their prevalence, associated morbidity, mortality, and cost. Furthermore, these three diseases are amenable to timely interventions and secondary prevention through telemonitoring. The preponderance of evidence from studies using rigorous research methods points to beneficial results from telemonitoring in its various manifestations, albeit with a few exceptions. Generally, the benefits include reductions in use of service: hospital admissions/re-admissions, length of hospital stay, and emergency department visits typically declined. It is important that there often were reductions in mortality. Few studies reported neutral or mixed findings.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140284/1/tmj.2014.9981.pd
The Hubble Deep Field: Observations, Data Reduction, and Galaxy Photometry
The Hubble Deep Field (HDF) is a Director's Discretionary program on HST in
Cycle 5 to image an undistinguished field at high Galactic latitude in four
passbands as deeply as reasonably possible. These images provide the most
detailed view to date of distant field galaxies and are likely to be important
for a wide range of studies in galaxy evolution and cosmology. In order to
optimize observing in the time available, a field in the northern continuous
viewing zone was selected and images were taken for ten consecutive days, or
approximately 150 orbits. Shorter 1-2 orbit images were obtained of the fields
immediately adjacent to the primary HDF in order to facilitate spectroscopic
follow-up by ground-based telescopes. The observations were made from 18 to 30
December 1995, and both raw and reduced data have been put in the public domain
as a community service.
We present a summary of the criteria for selecting the field, the rationale
behind the filter selection and observing times in each band, and the
strategies for planning the observations to maximize the exposure time while
avoiding earth-scattered light. Data reduction procedures are outlined, and
images of the combined frames in each band are presented. Objects detected in
these images are listed in a catalog with their basic photometric parameters.Comment: 37 pages, XX PostScript figures, uses aaspp4.sty astrobib.sty.
(Astrobib is available from http://www.stsci.edu/software/TeX.html .) To
appear the Astronomical Journal. More info on the Hubble deep field can be
found at http://www.stsci.edu/../ftp/observer/hdf/hdf.html . More figures
(images) can be found at
http://www.stsci.edu/../ftp/observer/hdf/references/williams/ and the full
source catalog is available at
http://www.stsci.edu/../ftp/observer/hdf/archive/v2catalog
National Telemedicine Initiatives: Essential to Healthcare Reform
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78116/1/tmj.2009.9960.pd
Evaluation Research and Institutional Pressures: Challenges in Public-Nonprofit Contracting
This article examines the connection between program evaluation research and decision-making by public managers. Drawing on neo-institutional theory, a framework is presented for diagnosing the pressures and conditions that lead alternatively toward or away the rational use of evaluation research. Three cases of public-nonprofit contracting for the delivery of major programs are presented to clarify the way coercive, mimetic, and normative pressures interfere with a sound connection being made between research and implementation. The article concludes by considering how public managers can respond to the isomorphic pressures in their environment that make it hard to act on data relating to program performance.This publication is Hauser Center Working Paper No. 23. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers
The HST/ACS Coma Cluster Survey. II. Data Description and Source Catalogs
The Coma cluster was the target of a HST-ACS Treasury program designed for
deep imaging in the F475W and F814W passbands. Although our survey was
interrupted by the ACS instrument failure in 2007, the partially completed
survey still covers ~50% of the core high-density region in Coma. Observations
were performed for 25 fields that extend over a wide range of cluster-centric
radii (~1.75 Mpc) with a total coverage area of 274 arcmin^2. The majority of
the fields are located near the core region of Coma (19/25 pointings) with six
additional fields in the south-west region of the cluster. In this paper we
present reprocessed images and SExtractor source catalogs for our survey
fields, including a detailed description of the methodology used for object
detection and photometry, the subtraction of bright galaxies to measure faint
underlying objects, and the use of simulations to assess the photometric
accuracy and completeness of our catalogs. We also use simulations to perform
aperture corrections for the SExtractor Kron magnitudes based only on the
measured source flux and half-light radius. We have performed photometry for
~73,000 unique objects; one-half of our detections are brighter than the
10-sigma point-source detection limit at F814W=25.8 mag (AB). The slight
majority of objects (60%) are unresolved or only marginally resolved by ACS. We
estimate that Coma members are 5-10% of all source detections, which consist of
a large population of unresolved objects (primarily GCs but also UCDs) and a
wide variety of extended galaxies from a cD galaxy to dwarf LSB galaxies. The
red sequence of Coma member galaxies has a constant slope and dispersion across
9 magnitudes (-21<M_F814W<-13). The initial data release for the HST-ACS Coma
Treasury program was made available to the public in 2008 August. The images
and catalogs described in this study relate to our second data release.Comment: Accepted for publication in ApJS. A high-resolution version is
available at http://archdev.stsci.edu/pub/hlsp/coma/release2/PaperII.pd
Integrative Analysis of the Mitochondrial Proteome in Yeast
In this study yeast mitochondria were used as a model system to apply, evaluate, and integrate different genomic approaches to define the proteins of an organelle. Liquid chromatography mass spectrometry applied to purified mitochondria identified 546 proteins. By expression analysis and comparison to other proteome studies, we demonstrate that the proteomic approach identifies primarily highly abundant proteins. By expanding our evaluation to other types of genomic approaches, including systematic deletion phenotype screening, expression profiling, subcellular localization studies, protein interaction analyses, and computational predictions, we show that an integration of approaches moves beyond the limitations of any single approach. We report the success of each approach by benchmarking it against a reference set of known mitochondrial proteins, and predict approximately 700 proteins associated with the mitochondrial organelle from the integration of 22 datasets. We show that a combination of complementary approaches like deletion phenotype screening and mass spectrometry can identify over 75% of the known mitochondrial proteome. These findings have implications for choosing optimal genome-wide approaches for the study of other cellular systems, including organelles and pathways in various species. Furthermore, our systematic identification of genes involved in mitochondrial function and biogenesis in yeast expands the candidate genes available for mapping Mendelian and complex mitochondrial disorders in humans
Localized topological changes of the plasma membrane upon exocytosis visualized by polarized TIRFM
Imaging of individual secretory granules reveals how exocytosis curves the membrane
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