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Structural Neuroimaging of Anorexia Nervosa: Future Directions in the Quest for Mechanisms Underlying Dynamic Alterations.
Anorexia nervosa (AN) is a serious eating disorder characterized by self-starvation and extreme weight loss. Pseudoatrophic brain changes are often readily visible in individual brain scans, and AN may be a valuable model disorder to study structural neuroplasticity. Structural magnetic resonance imaging studies have found reduced gray matter volume and cortical thinning in acutely underweight patients to normalize following successful treatment. However, some well-controlled studies have found regionally greater gray matter and persistence of structural alterations following long-term recovery. Findings from diffusion tensor imaging studies of white matter integrity and connectivity are also inconsistent. Furthermore, despite the severity of AN, the number of existing structural neuroimaging studies is still relatively low, and our knowledge of the underlying cellular and molecular mechanisms for macrostructural brain changes is rudimentary. We critically review the current state of structural neuroimaging in AN and discuss the potential neurobiological basis of structural brain alterations in the disorder, highlighting impediments to progress, recent developments, and promising future directions. In particular, we argue for the utility of more standardized data collection, adopting a connectomics approach to understanding brain network architecture, employing advanced magnetic resonance imaging methods that quantify biomarkers of brain tissue microstructure, integrating data from multiple imaging modalities, strategic longitudinal observation during weight restoration, and large-scale data pooling. Our overarching objective is to motivate carefully controlled research of brain structure in eating disorders, which will ultimately help predict therapeutic response and improve treatment
Intensive Pedestrian Survey of Selected Areas Within McAllister Park, San Antonio, Bexar County, Texas
Between September 19 and 22, 2005 the Center for Archaeological Research (CAR) of The University of Texas at San Antonio conducted a 100 percent intensive pedestrian survey within McAllister Park for the Parks and Recreation Department of the City of San Antonio. The survey was followed by an interview with Mr. Marvin Klar, a long-time resident of San Antonio and former owner of much of the land that is now part of McAllister Park. The Parks and Recreation Department is planning a series of improvements to existing facilities and the construction of new facilities within the boundaries of McAllister Park. Eleven separate areas will be impacted by these construction activities.
The goals of the pedestrian survey conducted by CAR were to identify and document all prehistoric and/or historic archaeological sites that may be impacted by the proposed improvements. Eight of the eleven areas were subject to the pedestrian survey. Artifacts constituting isolated finds were not collected unless they were temporally diagnostic. Archaeological investigations of the project area resulted in the location of two isolated finds in Areas 1 and 8 and the inspection of the northern boundary of site 41BX959, present in the southern portion of Area 9.
Additional work is not recommeded in association with the proposed improvements that are planned within McAllister Park. The deposits of site 41BX959 have been disturbed by earth moving activities, and therefore have little to no research potential. The portion of the site located in Area 9 is not recommended for listing to the National Register of Historic Places or for designation as a State Archaeological Landmark
Observations of the Ca II K line in Hel0830A dark points on August 3, 1985
Spectroheliograms taken in the light of He I 10830 A at the National Solar Observatory Vacuum Telescope on Kitt Peak were used to identify coronal holes and bright points (BPs). Target points were identified, coordinates calculated, and spectra recorded. For each spectrum, the difference in wavelength between the Ca II K minimum and the FeI reference line was calculated. It was noteworthy that the overall effect is a blueshift. It should be noted that if material of chromospheric density moves outward at this velocity, it could supply the mass flux of the solar wind if this chromospheric flow was concentrated in a few dozen sources, each of a diameter of a few arc seconds
Latent protein trees
Unbiased, label-free proteomics is becoming a powerful technique for
measuring protein expression in almost any biological sample. The output of
these measurements after preprocessing is a collection of features and their
associated intensities for each sample. Subsets of features within the data are
from the same peptide, subsets of peptides are from the same protein, and
subsets of proteins are in the same biological pathways, therefore, there is
the potential for very complex and informative correlational structure inherent
in these data. Recent attempts to utilize this data often focus on the
identification of single features that are associated with a particular
phenotype that is relevant to the experiment. However, to date, there have been
no published approaches that directly model what we know to be multiple
different levels of correlation structure. Here we present a hierarchical
Bayesian model which is specifically designed to model such correlation
structure in unbiased, label-free proteomics. This model utilizes partial
identification information from peptide sequencing and database lookup as well
as the observed correlation in the data to appropriately compress features into
latent proteins and to estimate their correlation structure. We demonstrate the
effectiveness of the model using artificial/benchmark data and in the context
of a series of proteomics measurements of blood plasma from a collection of
volunteers who were infected with two different strains of viral influenza.Comment: Published in at http://dx.doi.org/10.1214/13-AOAS639 the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
COMPARISON OF DRUG EFFECTS ON FIXEDâRATIO PERFORMANCE AND CHAIN PERFORMANCE MAINTAINED UNDER A SECONDâORDER FIXEDâRATIO SCHEDULE
In one component of a multiple schedule, pigeons were required to complete the same fourâresponse chain each session by responding sequentially on three identically lighted keys in the presence of four successively presented colors (chain performance). Food presentation occurred after five completions of the chain (i.e., after 20 correct responses). Errors, such as responding on the center or right key when the left was designated correct, produced a brief timeout but did not reset the chain. In the other component, responding on a single key (lighted white) was maintained by food presentation under a fixedâratio 20 schedule. In general, phencyclidine and dâamphetamine produced doseâdependent decreases in the overall response rates in both components. With pentobarbital, overall rate in each component generally increased at intermediate doses and decreased at higher doses. All three drugs produced doseâdependent disruptive effects on chainâperformance accuracy. Phencyclidine and pentobarbital increased percent errors at doses that had little or no rateâdecreasing effects, whereas dâamphetamine generally increased percent errors only at doses that substantially decreased overall rate. At high doses, all three drugs produced greater disruption of chain performance than of fixedratio performance, as indicated by a slower return to control responding, although the effects of dâamphetamine were less selective than those of phencyclidine or pentobarbital. 1985 Society for the Experimental Analysis of Behavio
Probing the 5th Dimension with the QCD String
A salient feature of String/Gauge duality is an extra 5th dimension. Here we
study the effect of confining deformations of AdS5 and compute the spectrum of
a string stretched between infinitely massive quarks and compare it with the
quantum states of the QCD flux as determined by Kuti, Juge and Morningstar in
lattice simulations. In the long flux tube limit the AdS string probes the
metric near the IR cutoff of the 5th dimension with a spectrum approximated by
a Nambu-Goto string in 4-d flat space, whereas at short distance the string
moves to the UV region with a discrete spectrum for pure AdS5. We also review
earlier results on glueballs states and the cross-over between hard and soft
diffractive scattering that support this picture.Comment: 12 pages, 4 figures, invited talk by Brower and Tan at the Eighth
Workshop on Non-Perturbative Quantum Chromodynamcis, June (2004
Plans for the International Heliophysical Year (IHY)
The International Heliophysical Year (IHY), an international program of scientific collaboration to understand the external drivers of planetary environments, will be conducted in 2007. This will be a major international event of great interest to the member States. The IHY will involve the deployment of new instrumentation, new observations from the ground and in space, and an education component. The IHY 2007 will coincide with the fiftieth anniversary of the International Geophysical Year (IGY) in 1957. The IGY was organized to study global phenomena of the Earth and Geospace involving about thousands of scientists from many nations, working at thousands of stations, around the world to obtain simultaneous, global observations from the ground and space. Building on results obtained during IGY 1957, the IHY will expand to the study of universal processes in the solar system that affect the interplanetary and terrestrial environments. The study of energetic events in the solar system will pave the way for safe human space travel to the Moon and planets in the future, and it will serve to inspire the next generation of space physicists
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