10,733 research outputs found
Driving usage – what are publishers and librarians doing to evaluate and promote usage?
Although a relatively recent phenomenon, measuring the usage of published research has rapidly become one of the most important ways to evaluate the relative value of different publications. Libraries and publishers are also investigating the impact of interface and technology provision in improving resource discovery and content usage. Demand for such data is increasing throughout the industry, partly in response to greater scrutiny of return on investment. As a result the techniques used by publishers and librarians to promote and evaluate usage are also developing. This paper looks at some of the methods currently adopted and examines the issues faced by the industry in driving forward the application of usage data
Examination of Methylation Sites for Forensic Age Determination from Semen
Methylation Sensitive High-Resolution Melt (MS-HRM) is based on quantitating the melt curve from an experimental sample against a standard of known methylation levels. Whereas most applications of age prediction using methylation markers are based upon pyrosequencing or SNaPshot technologies, these analysis methods are both cost and instrumentation prohibitive. This study sought to use to the varied methylation status of the ELOVL2 and FHL2 alleles, both having known correlation with age (Hamano et. al.), in a labor and time efficient manner to develop an age prediction model. A non-linear regression and standard curve was compiled from the methylation status in a sample (n=7) of extracted semen samples and compared to chronological age. The methylation status of ELVOL2 and FHL2 from each sample was obtained, with the conclusion that no correlation in methylation percentage and biological age existed for this sample of individuals aged 20-33. The principal objective of this study, to expand the application of MS-HRM age prediction from blood to other body fluids, will need further testing using larger sample sizes and broader age ranges prior to application in forensic casework.https://scholarscompass.vcu.edu/uresposters/1281/thumbnail.jp
Predictability of Critical Transitions
Critical transitions in multistable systems have been discussed as models for
a variety of phenomena ranging from the extinctions of species to
socio-economic changes and climate transitions between ice-ages and warm-ages.
From bifurcation theory we can expect certain critical transitions to be
preceded by a decreased recovery from external perturbations. The consequences
of this critical slowing down have been observed as an increase in variance and
autocorrelation prior to the transition. However especially in the presence of
noise it is not clear, whether these changes in observation variables are
statistically relevant such that they could be used as indicators for critical
transitions. In this contribution we investigate the predictability of critical
transitions in conceptual models. We study the quadratic integrate-and-fire
model and the van der Pol model, under the influence of external noise. We
focus especially on the statistical analysis of the success of predictions and
the overall predictability of the system. The performance of different
indicator variables turns out to be dependent on the specific model under study
and the conditions of accessing it. Furthermore, we study the influence of the
magnitude of transitions on the predictive performance
The Media’s Influence in Everyday Life on Women’s Perception of Body Image
Many women are not satisfied with their current body figures and frequently attempt to improve their figure. Body image discrepancies occur when a comparison between “actual” self to either “ought” or “ideal” selves don’t match up. If there is a difference between these two self-guides then a discrepancy exists. According to a national survey, half of women report negative evaluations of their appearance and worry about being or becoming overweight. One of the strongest socio-cultural pressures that women face with their body image is the media, such as magazines and television. Studies have shown that when exposed to thin body images depicted in the media, women often experience body dissatisfaction. Studies on the media and body dissatisfaction have, in general, only been conducted in a laboratory setting, which has limited ecological validity. Additionally, some findings are problematic because self-reported data can be systematically biased if they require participants to recall information over long periods of time. This study uses Ecological Momentary Assessment (EMA) to record daily media usage and body image discrepancies in participants’ natural environment at the moment(s) it occurs. During a two-week period, 63 female college undergraduates carried a Palm Pilot and when an alarm sounded (5 times daily) they reported television and magazine usage and body image discrepancies. On average, women reported having watched television during 28% of the assessments. During these times, they most often watched comedies (37.7% of the time), dramas (23.2%) and reality programs (23%). Individuals read magazines during 3% of the reports, most commonly read beauty (65.2%) and gossip magazines (42.5%). Results show that women reported body image dissatisfaction yet there was no momentary relationship between media exposure and body image discrepancy in these women’s daily lives. Women reporting more self-objectification or disordered eating watched more television and read more magazines, respectively. Discussion addresses future directions relating EMA usage and body image discrepancy and other ways media effects women
Graph Representations for Higher-Order Logic and Theorem Proving
This paper presents the first use of graph neural networks (GNNs) for
higher-order proof search and demonstrates that GNNs can improve upon
state-of-the-art results in this domain. Interactive, higher-order theorem
provers allow for the formalization of most mathematical theories and have been
shown to pose a significant challenge for deep learning. Higher-order logic is
highly expressive and, even though it is well-structured with a clearly defined
grammar and semantics, there still remains no well-established method to
convert formulas into graph-based representations. In this paper, we consider
several graphical representations of higher-order logic and evaluate them
against the HOList benchmark for higher-order theorem proving
Wormholes Immersed in Rotating Matter
We demonstrate that rotating matter sets the throat of an Ellis wormhole into
rotation, allowing for wormholes which possess full reflection symmetry with
respect to the two asymptotically flat spacetime regions. We analyze the
properties of this new type of rotating wormholes and show that the wormhole
geometry can change from a single throat to a double throat configuration. We
further discuss the ergoregions and the lightring structure of these wormholes.Comment: 8 pages, 5 figue
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