Search results for " frequency"
showing 10 items of 1398 documents
Lexical competition is enhanced in the left hemisphere: Evidence from different types of orthographic neighbors
2007
Two divided visual field lexical decision experiments were conducted to examine the role of the cerebral hemispheres in orthographic neighborhood effects. In Experiment 1, we employed two types of words: words with many substitution neighbors (high-N) and words with few substitution neighbors (low-N). Results showed a facilitative effect of N in the left visual field (i.e., right hemisphere) and an inhibitory effect of N in the right visual field (left hemisphere). In Experiment 2, we examined whether the inhibitory effect of the higher frequency neighbors increases in the left hemisphere as compared to the right hemisphere. To go beyond the usual N-metrics, we selected words with (or witho…
No association of alcohol dependence with HOMER 1 and 2 genetic variants.
2010
Several lines of evidence indicate that alterations of the central cortico-accumbens glutamate pathway are involved in the development and maintenance of alcohol- and substance-use disorders. The HOMER protein family is encoded by 3 genes HOMER (1–3) which are components of the excitatory postsynaptic density complex and function to modulate synaptic activity by the regulation of glutamate signaling. HOMER 1 and 2 have been reported to contribute to chronic alcohol-induced long-term neurochemical changes in the endogenous reward system. Data from animal models suggest a potential role of the Homer protein family in the development of alcohol and substance use. The aim of this study is to as…
Association of Common Variants in NPPA and NPPB with Circulating Natriuretic Peptides and Blood Pressure
2009
We examined the association of common variants at the NPPA-NPPB locus with circulating concentrations of the natriuretic peptides, which have blood pressure-lowering properties. We genotyped SNPs at the NPPA-NPPB locus in 14,743 individuals of European ancestry, and identified associations of plasma atrial natriuretic peptide with rs5068 (P = 8 x 10(-70)), rs198358 (P = 8 x 10(-30)) and rs632793 (P = 2 x 10(-10)), and of plasma B-type natriuretic peptide with rs5068 (P = 3 x 10(-12)), rs198358 (P = 1 x 10(-25)) and rs632793 (P = 2 x 10(-68)). In 29,717 individuals, the alleles of rs5068 and rs198358 that showed association with increased circulating natriuretic peptide concentrations were a…
Accommodative stimulus-response curves to low-pass filtered natural images
2018
To assess how the monocular steady-state accommodative stimulus-response curve is modified when viewing low-pass filtered natural images. Eighteen adult subjects participated in the study. The accommodative stimulus-response curve was objectively assessed by means of a Hartmann-Shack wavefront sensor. Measurements were taken at different accommodative demands. Target images were low-pass filtered versions of a natural image that were obtained applying different digital spatial filters that limited the spatial frequency content of the natural image. Cutoff spatial frequencies were set at 30, 21, and 15 cycles per degree (cy/deg). Mean data obtained for each target were fitted to linear model…
Effect of luminance on photopic visual acuity in the presence of laser speckle
1988
Visual acuity in coherent and incoherent light has been determined by using square-wave gratings of 100% contrast. Luminance was varied from 3 to 400 cd/m2. Coherent illumination resulted in a 40% loss of visual acuity. This is probably due to the masking effect of coherent spatial noise (speckle). However, the most interesting finding is the change in shape of the photopic visual-acuity-luminance function. With coherent illumination, the function is vertically displaced and of a different gradient. An increase in luminance produces a decrease in visual acuity. This indicates that the masking effect of the speckle is dependent on luminance. Two observers were used, and similar results were …
Validation of a short questionnaire to qualitatively assess the intake of total fat, saturated, monounsaturated, polyunsaturated fatty acids, and cho…
2003
Background To validate a self-administered 20-item short questionnaire (SQ) for classifying individuals according to their intake of total fat, saturated (SFA), monounsaturated (MUFA), and polyunsaturated fatty acids (PUFA), as well as cholesterol. Methods The SQ was sent to a randomly selected subsample of 300 participants of the European Prospective Investigation into Cancer and Nutrition (EPIC) in Heidelberg. The SQ was sent back by 244 participants (52.5% women, 47.5% men). Intake of total fat, SFA, MUFA, PUFA, and cholesterol was calculated from a 148-item food frequency questionnaire (FFQ). The intake was compared with the scores computed from the SQ. Results Spearman's correlation…
Analyzing gastrocnemius EMG-activity and sway data from quiet and perturbed standing.
2007
In an experiment, we combined force plate measurements and surface EMG in studying quiet and perturbed standing, involving MS (Multiple sclerosis) and controls. The aim of this paper is to report the results thus obtained on the relation between filtered gastrocnemius (GA) EMG and the anterior-posterior center-of-pressure (A/P COP) coordinate. The main finding is the good correspondence between A/P COP and the filtered GA EMG in the low frequency range. The EMG envelope was calculated using a zero-lag filter. Combining this with time shifts around 250-350 ms produced a high correlation (85.5+/-8.4%) between the GA-EMG envelope and the A/P COP. This EMG-COP relation was closest when using a …
Large-scale association analysis identifies 13 new susceptibility loci for coronary artery disease
2011
1. The CARDIoGRAM Consortium. Large-scale association analysis identifies 13 new susceptibility loci for coronary artery disease. Nature Genetics. 2011;43:333–338. ### Study Hypothesis Recently, genome-wide association studies (GWAS) have identified several common variants that are associated with risk of coronary artery disease (CAD) and myocardial infarction (MI). The authors state that the current loci discovered in CAD and MI GWAS explain only a small fraction of the heritability of this complex disease. The authors hypothesized that a larger study would provide more power to discover common variants with modest effect sizes. Therefore, they formed the Coronary ARtery DIsease Genome-wid…
Lack of association between estrogen receptor 1 gene polymorphisms and multiple sclerosis in southern Italy in humans
2002
Estrogen receptor 1 gene polymorphisms (ESR1) have been found to be associated with multiple sclerosis (MS) in both Japanese and Finnish populations. We investigated the association between ESR1 polymorphisms (PvuII and XbaI) and MS in a study of 132 MS patients and 129 controls from the same geographic background (southern Italy). Allelic and genotypic frequencies were not different between MS patients and population controls for either the PvuII or XbaI polymorphism. This result suggests that the association between a given disease and a genomic characteristic must be confirmed by separate investigations in different populations. © 2002 Elsevier Science Ireland Ltd. All rights reserved.
REEP1 mutation spectrum and genotype/phenotype correlation in hereditary spastic paraplegia type 31.
2008
Contains fulltext : 71291.pdf (Publisher’s version ) (Closed access) Mutations in the receptor expression enhancing protein 1 (REEP1) have recently been reported to cause autosomal dominant hereditary spastic paraplegia (HSP) type SPG31. In a large collaborative effort, we screened a sample of 535 unrelated HSP patients for REEP1 mutations and copy number variations. We identified 13 novel and 2 known REEP1 mutations in 16 familial and sporadic patients by direct sequencing analysis. Twelve out of 16 mutations were small insertions, deletions or splice site mutations. These changes would result in shifts of the open-reading-frame followed by premature termination of translation and haploins…