Project description:This study explored whether there is a gender difference in letter-sound knowledge when children start at school. 485 children aged 5-6 years completed assessment of letter-sound knowledge, i.e., large letters; sound of large letters; small letters; sound of small letters. The findings indicate a significant difference between girls and boys in all four factors tested in this study in favor of the girls. There are still no clear explanations to the basis of a presumed gender difference in letter-sound knowledge. That the findings have origin in neuro-biological factors cannot be excluded, however, the fact that girls probably have been exposed to more language experience/stimulation compared to boys, lends support to explanations derived from environmental aspects.
Project description:Modulation of gene expression through epigenetic signaling has recently emerged as a novel approach in treating human disease. Specifically, chromatin reader proteins, which mediate protein-protein interactions via binding to modified lysine residues, are gaining traction as potential therapeutic targets. Herein, we review recent efforts to understand and modulate the activity of chromatin reader proteins with small-molecule ligands.
Project description:Reading, an essential life skill in modern society, is typically learned during childhood. Adults who can read show white matter differences compared to adults who never learned to read. Studies have not established whether children who can read show similar white matter differences compared to children who cannot read. We compared 6-year old children who could decode written English words and pseudowords (n = 31; Readers) and 6-year old children who could not decode pseudowords and had a standard score <100 on a task for reading single words (n = 11; Pre-readers). We employed diffusion MRI and tractography to extract fractional anisotropy (FA) along the trajectory of six bilateral intra-hemispheric tracts and two posterior subdivisions of the corpus callosum. Readers demonstrated significantly increased FA within the left anterior segment of the superior longitudinal fasciculus (aSLF-L) and the right uncinate fasciculus (UF-R) compared to Pre-readers. FA in the aSLF-L was significantly correlated with phonological awareness; FA in the UF-R was significantly correlated with language. Correlations in the UF-R but not the aSLF-L remained significant after controlling for reading ability, revealing that UF-R group differences were related to both children's language and reading abilities. Taken together, these findings demonstrate new evidence showing that individual differences in white matter structure relate to whether children have begun to read.
Project description:Reading serves many ends. Some readers report that works of fiction provide an imaginative escape from the rigors of life, others report reading in order to be intellectually challenged. While various characterizations of readers' engagement with prose fiction have been proposed, few have been checked using representative samples of readers. Our research reports on reader self-descriptions observed in a representative sample of 501 adults in the Netherlands. Reader self-descriptions exhibit regularities, with certain self-descriptions predicting others. Contrary to existing theories which posit two types of readers characterized by non-overlapping concerns (identifying readers and distanced readers), we find that while some readers attend to plot structure or read in order to be intellectually challenged, reader self-descriptions overlap more than received theories predict. We hypothesize that some readers have cultivated more reading techniques than others, with educated or experienced readers tending to report deriving additional experiences from reading.
Project description:The eukaryotic sliding clamp, proliferating cell nuclear antigen (PCNA), acts as a central coordinator of DNA transactions by providing a multivalent interaction surface for factors involved in DNA replication, repair, chromatin dynamics and cell cycle regulation. Posttranslational modifications (PTMs), such as mono- and polyubiquitylation, sumoylation, phosphorylation and acetylation, further expand the repertoire of PCNA's binding partners. These modifications affect PCNA's activity in the bypass of lesions during DNA replication, the regulation of alternative damage processing pathways such as homologous recombination and DNA interstrand cross-link repair, or impact on the stability of PCNA itself. In this review, we summarise our current knowledge about how the PTMs are "read" by downstream effector proteins that mediate the appropriate action. Given the variety of interaction partners responding to PCNA's modified forms, the ensemble of PCNA modifications serves as an instructive model for the study of biological signalling through PTMs in general.
Project description:Histone modifications not only play important roles in regulating chromatin structure and nuclear processes but also can be passed to daughter cells as epigenetic marks. Accumulating evidence suggests that the key function of histone modifications is to signal for recruitment or activity of downstream effectors. Here, we discuss the latest discovery of histone-modification readers and how the modification language is interpreted.
Project description:Background?Letters of recommendation (LORs) are an important part of applications for residency and fellowship programs. Despite anecdotal use of a "code" in LORs, research on program director (PD) perceptions of the value of these documents is sparse.Objective?We analyzed PD interpretations of LOR components and discriminated between perceived levels of applicant recommendations.Methods?We conducted a cross-sectional, descriptive study of pediatrics residency and fellowship PDs. We developed a survey asking PDs to rate 3 aspects of LORs: 13 letter features, 10 applicant abilities, and 11 commonly used phrases, using a 5-point Likert scale. The 11 phrases were grouped using principal component analysis. Mean scores of components were analyzed with repeated-measures analysis of variance. Median Likert score differences between groups were analyzed with Mann-Whitney U tests.Results?Our survey had a 43% response rate (468 of 1079). "I give my highest recommendation" was rated the most positive phrase, while "showed improvement" was rated the most negative. Principal component analysis generated 3 groups of phrases with moderate to strong correlation with each other. The mean Likert score for each group from the PD rating was calculated. Positive phrases had a mean (SD) of 4.4 (0.4), neutral phrases 3.4 (0.5), and negative phrases 2.6 (0.6). There was a significant difference among all 3 pairs of mean scores (all P < .001).Conclusions?Commonly used phrases in LORs were interpreted consistently by PDs and influenced their impressions of candidates. Key elements of LORs include distinct phrases depicting different degrees of endorsement.
Project description:The quest for information is one of the most common activity of human beings. Despite the the impressive progress of search engines, not to miss the needed piece of information could be still very tough, as well as to acquire specific competences and knowledge by shaping and following the proper learning paths. Indeed, the need to find sensible paths in information networks is one of the biggest challenges of our societies and, to effectively address it, it is important to investigate the strategies adopted by human users to cope with the cognitive bottleneck of finding their way in a growing sea of information. Here we focus on the case of Wikipedia and investigate a recently released dataset about users' click on the English Wikipedia, namely the English Wikipedia Clickstream. We perform a semantically charged analysis to uncover the general patterns followed by information seekers in the multi-dimensional space of Wikipedia topics/categories. We discover the existence of well defined strategies in which users tend to start from very general, i.e., semantically broad, pages and progressively narrow down the scope of their navigation, while keeping a growing semantic coherence. This is unlike strategies associated to tasks with predefined search goals, namely the case of the Wikispeedia game. In this case users first move from the 'particular' to the 'universal' before focusing down again to the required target. The clear picture offered here represents a very important stepping stone towards a better design of information networks and recommendation strategies, as well as the construction of radically new learning paths.