Criterial Noise Effects on Rule-Based Category Learning: The Impact of Delayed Feedback

Variability in the representation of the decision criterion is assumed in many category learning models yet few studies have directly examined its impact. On each trial, criterial noise should result in drift in the criterion and will negatively impact categorization accuracy, particularly in rule-based categorization tasks where learning depends upon the maintenance and manipulation of decision criteria. The results of three experiments test this hypothesis and examine the impact of working memory on slowing the drift rate. Experiment 1 examined the effect of drift by inserting a 5 s delay between the categorization response and the delivery of corrective feedback, and working memory demand was manipulated by varying the number of decision criteria to be learned. Delayed feedback adversely affected performance, but only when working memory demand was high. Experiment 2 built upon a classic finding in the absolute identification literature and demonstrated that distributing the criteria across multiple dimensions decreases the impact of drift during the delay. Experiment 3 confirmed that the effect of drift during the delay is moderated by working memory. These results provide important insights into the interplay between criterial noise and working memory as well as providing important constraints for models of rule-based category learning

Oral diabetes medication monotherapy and short-term mortality in individuals with type 2 diabetes and coronary artery disease

Objective To determine whether sulfonylurea use, compared with non-sulfonylurea oral diabetes medication use, was associated with 2-year mortality in individuals with well-controlled diabetes and coronary artery disease (CAD). Research design and methods We studied 5352 US veterans with type 2 diabetes, obstructive CAD on coronary angiography, hemoglobin A1c ≤7.5% at the time of catheterization, and taking zero or one oral diabetes medication (categorized as no medications, non-sulfonylurea medication, or sulfonylurea). We estimated the association between medication category and 2-year mortality using inverse probability of treatment-weighted (IPW) standardized mortality differences and IPW multivariable Cox proportional hazards regression. Results 49%, 35%, and 16% of the participants were on no diabetes medications, non-sulfonylurea medications, and sulfonylureas, respectively. In individuals on no medications, non-sulfonylurea medications, and sulfonylureas, the unadjusted mortality rates were 6.6%, 5.2%, and 11.9%, respectively, and the IPW-standardized mortality rates were 5.9%, 6.5%, and 9.7%, respectively. The standardized absolute 2-year mortality difference between non-sulfonylurea and sulfonylurea groups was 3.2% (95% CI 0.7 to 5.7) (p=0.01). In Cox proportional hazards models, the point estimate suggested that sulfonylurea use might be associated with greater hazard of mortality than non-sulfonylurea medication use, but this finding was not statistically significant (HR 1.38 (95% CI 1.00 to 1.93), p=0.05). We did not observe significant mortality differences between individuals on no diabetes medications and non-sulfonylurea users. Conclusions Sulfonylurea use was common (nearly one-third of those taking medications) and was associated with increased 2-year mortality in individuals with obstructive CAD. The significance of the association between sulfonylurea use and mortality was attenuated in fully adjusted survival models. Caution with sulfonylurea use may be warranted for patients with well-controlled diabetes and CAD, and metformin or newer diabetes medications with cardiovascular safety data could be considered as alternatives when individualizing therapy

The Effectiveness of Telemedicine for Weight Management in the MOVE! Program

PURPOSE: To examine the effectiveness of videoconferencing technology for delivering comprehensive weight management treatment.METHODS: This retrospective cohort study was conducted by extraction of data from medical records for the years 2008-2010. The treatment included a series of 12 weekly MOVE!® classes delivered using videoconferencing. Data were extracted from the time of baseline weight to 1 year after baseline weight for the MOVE! participants (n = 60) and from a concurrent control group (n = 60) that did not participate in MOVE! treatment.FINDINGS: Results indicated that the MOVE! group lost weight while the control group gained weight, resulting in a mean difference between the groups of -5.5 ± 2.7 kg (95% CI = -8.0 to -3.0; P \u3c .0001).CONCLUSIONS: These results indicate that videoconferencing is an effective method to provide the MOVE! Weight Management Program to veterans. Weight loss was maintained for one year after baseline in the MOVE! group. This is very promising as weight re-gain is a common issue and these results support using videoconferencing for a long-term weight management treatment option

Dynamics of glomerular ultrafiltration: VI. Studies in the primate

Dynamics of glomerular ultrafiltration: VI. Studies in the primate. Pressures and flows were measured in accessible surface glomeruli of the squirrel monkey under conditions of normal hydropenia. Mean glomerular capillary hydrostatic pressure and the mean glomerular transcapillary hydrostatic pressure difference (ΔP) averaged approximately 45 mm Hg and 35 mm Hg, respectively. These findings are in close accord with recent direct estimates in the rat. The net driving force for ultrafiltration was found to decline from a maximum value of about 12 mm Hg at the afferent end of the glomerular capillary network essentially to zero by the efferent end, indicating that, in the monkey as in the rat, filtration pressure equilibrium is achieved under normal hydropenic conditions. The monkey differs from the rat in one important respect, however, in that, as has long been recognized, the monkey tends to have higher systemic total plasma protein concentrations (CA) than the rat. This is of interest since monkey, like man, is found to have lower filtration fractions than the rat. Since ΔP is found to be essentially similar in monkey and rat, and since, at filtration pressure equilibrium, filtration fraction is determined by ΔP and CA, these observed differences in filtration fraction between rodent and primate must therefore be due to these differences in CA

Decibel: the relational dataset branching system

As scientific endeavors and data analysis become increasingly collaborative, there is a need for data management systems that natively support the versioning or branching of datasets to enable concurrent analysis, cleaning, integration, manipulation, or curation of data across teams of individuals. Common practice for sharing and collaborating on datasets involves creating or storing multiple copies of the dataset, one for each stage of analysis, with no provenance information tracking the relationships between these datasets. This results not only in wasted storage, but also makes it challenging to track and integrate modifications made by different users to the same dataset. In this paper, we introduce the Relational Dataset Branching System, Decibel, a new relational storage system with built-in version control designed to address these short-comings. We present our initial design for Decibel and provide a thorough evaluation of three versioned storage engine designs that focus on efficient query processing with minimal storage overhead. We also develop an exhaustive benchmark to enable the rigorous testing of these and future versioned storage engine designs.National Science Foundation (U.S.) (1513972)National Science Foundation (U.S.) (1513407)National Science Foundation (U.S.) (1513443)Intel Science and Technology Center for Big Dat

Projection, Spatial Correlations, and Anisotropies in a Large and Complete Sample of Abell Clusters

An analysis of R >= 1 Abell clusters is presented for samples containing recent redshifts from the MX Northern Abell Cluster Survey. The newly obtained redshifts from the MX Survey as well as those from the ESO Nearby Abell Cluster Survey (ENACS) provide the necessary data for the largest magnitude-limited correlation analysis of rich clusters in the entire sky (excluding the galactic plane) to date. We find 19.4 <= r_0 <= 23.3 h^-1Mpc, -1.92 <= gamma <= -1.83 for four different subsets of Abell/ACO clusters, including a large sample (N=104) of cD clusters. We have used this dataset to look for line-of-sight anisotropies within the Abell/ACO catalogs. We show that the strong anisotropies present in previously studied Abell cluster datasets are not present in our R >= 1 samples. There are, however, indications of residual anisotropies which we show are the result of two elongated superclusters, Ursa Majoris and Corona Borealis, whose axes lie near the line-of-sight. After rotating these superclusters so that their semi-major axes are prependicular to the line-of-sight, we find no anisotropies as indicated by the correlation function. The amplitude and slope of the two-point correlation function remain the same before and after these rotations. We also remove a subset of R = 1 Abell/ACO clusters that show sizable foreground/background galaxy contamination and again find no change in the amplitude or slope of the correlation function. We conclude that the correlation length of R >= 1 Abell clusters is not artificially enhanced by line-of-sight anisotropies.Comment: 37 pages, 8 figures, AASTeX Accepted for publication in Ap

NYU-VAGC: a galaxy catalog based on new public surveys

Here we present the New York University Value-Added Galaxy Catalog (NYU-VAGC), a catalog of local galaxies (mostly below a redshift of about 0.3) based on a set of publicly-released surveys (including the 2dFGRS, 2MASS, PSCz, FIRST, and RC3) matched to the Sloan Digital Sky Survey (SDSS) Data Release 2. Excluding areas masked by bright stars, the photometric sample covers 3514 square degrees and the spectroscopic sample covers 2627 square degrees (with about 85% completeness). Earlier, proprietary versions of this catalog have formed the basis of many SDSS investigations of the power spectrum, correlation function, and luminosity function of galaxies. We calculate and compile derived quantities (for example, K-corrections and structural parameters for galaxies). The SDSS catalog presented here is photometrically recalibrated, reducing systematic calibration errors across the sky from about 2% to about 1%. We include an explicit description of the geometry of the catalog, including all imaging and targeting information as a function of sky position. Finally, we have performed eyeball quality checks on a large number of objects in the catalog in order to flag deblending and other errors. This catalog is complementary to the SDSS Archive Servers, in that NYU-VAGC's calibration, geometrical description, and conveniently small size are specifically designed for studying galaxy properties and large-scale structure statistics using the SDSS spectroscopic catalog.Comment: accepted by AJ; full resolution version available at http://sdss.physics.nyu.edu/vagc/va_paper.ps; data files available at http://sdss.physics.nyu.edu/vagc

Extragalactic Foregrounds of the Cosmic Microwave Background: Prospects for the MAP Mission

(Abridged) While the major contribution to the Cosmic Microwave Background (CMB) anisotropies are the sought-after primordial fluctuations produced at the surface of last scattering, other effects produce secondary fluctuations at lower redshifts. Here, we study the extragalactic foregrounds of the CMB in the context of the upcoming MAP mission. We first survey the major extragalactic foregrounds and show that discrete sources, the Sunyaev-Zel'dovich (SZ) effect, and gravitational lensing are the most dominant ones for MAP. We then show that MAP will detect (>5 sigma) about 46 discrete sources and 10 SZ clusters directly with 94 GHz fluxes above 2 Jy. The mean SZ fluxes of fainter clusters can be probed by cross-correlating MAP with cluster positions extracted from existing catalogs. For instance, a MAP-XBACs cross-correlation will be sensitive to clusters with S(94GHz)>200mJy, and will thus provide a test of their virialization state and a measurement of their gas fraction. Finally, we consider probing the hot gas on supercluster scales by cross-correlating the CMB with galaxy catalogs. Assuming that galaxies trace the gas, we show that a cross-correlation between MAP and the APM catalog should yield a marginal detection, or at least a four-fold improvement on the COBE upper limits for the rms Compton y-parameter.Comment: 27 LaTeX pages, including 5 ps figures and 2 tables. To appear in ApJ. Minor revisions to match accepted version. Color figures and further links available at http://www.astro.princeton.edu/~refreg

Satellite studies of severe convective storms

Co-authors by section, 2.0 Donald W. Hillger, 3.0 Andrew J. Negri, 4.0 Robert A Maddox, 5.0 David W. Reynolds.June 1978.Includes bibliographical references (pages 63-65).Final Report sponsored by NSF, Atmopheric Science Section ATM76-2103