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11.
John?F?StinsEmail author G?Caroline?M?van Baal Tinca?JC?Polderman Frank?C?Verhulst Dorret?I?Boomsma 《BMC neuroscience》2004,5(1):49
Background
There is great interest in appropriate phenotypes that serve as indicator of genetically transmitted frontal (dys)function, such as ADHD. Here we investigate the ability to deal with response conflict, and we ask to what extent performance variation on response interference tasks is caused by genetic variation. We tested a large sample of 12-year old monozygotic and dizygotic twins on two well-known and closely related response interference tasks; the color Stroop task and the Eriksen flanker task. Using structural equation modelling we assessed the heritability of several performance indices derived from those tasks. 相似文献12.
13.
DNA sequence of both chromosomes of the cholera pathogen Vibrio cholerae 总被引:23,自引:0,他引:23
Heidelberg JF Eisen JA Nelson WC Clayton RA Gwinn ML Dodson RJ Haft DH Hickey EK Peterson JD Umayam L Gill SR Nelson KE Read TD Tettelin H Richardson D Ermolaeva MD Vamathevan J Bass S Qin H Dragoi I Sellers P McDonald L Utterback T Fleishmann RD Nierman WC White O Salzberg SL Smith HO Colwell RR Mekalanos JJ Venter JC Fraser CM 《Nature》2000,406(6795):477-483
14.
Sakari Leino Patrick JC May Paavo Alku Lassi A Liikkanen Hannu Tiitinen 《BMC neuroscience》2007,8(1):78
Background
In the field of auditory neuroscience, much research has focused on the neural processes underlying human sound localization. A recent magnetoencephalography (MEG) study investigated localization-related brain activity by measuring the N1m event-related response originating in the auditory cortex. It was found that the dynamic range of the right-hemispheric N1m response, defined as the mean difference in response magnitude between contralateral and ipsilateral stimulation, reflects cortical activity related to the discrimination of horizontal sound direction. Interestingly, the results also suggested that the presence of realistic spectral information within horizontally located spatial sounds resulted in a larger right-hemispheric N1m dynamic range. Spectral cues being predominant at high frequencies, the present study further investigated the issue by removing frequencies from the spatial stimuli with low-pass filtering. This resulted in a stepwise elimination of direction-specific spectral information. Interaural time and level differences were kept constant. The original, unfiltered stimuli were broadband noise signals presented from five frontal horizontal directions and binaurally recorded for eight human subjects with miniature microphones placed in each subject's ear canals. Stimuli were presented to the subjects during MEG registration and in a behavioral listening experiment. 相似文献15.
Deep level transient spectroscopy (DLTS) and Laplace-DLTS (L-DLTS) have been used to investigate defects in an n-type GaAs before and after exposure to a dc hydrogen plasma (hydrogenation). DLTS revealed the presence of three prominent electron traps in the material in the temperature range 20-300 K. However, L-DLTS with its higher resolution enabled the splitting of two narrowly spaced emission rates. Consequently four electron traps at, EC—0.33 eV, EC—0.36 eV, EC—0.38 eV and EC—0.56 eV were observed in the control sample. Following hydrogenation, all these traps were passivated with a new complex (presumably the M3), emerging at EC—0.58 eV. Isochronal annealing of the passivated material between 50 and 300 °C, revealed the emergence of a secondary defect, not previously observed, at EC—0.37 eV. Finally, the effect of hydrogen passivation is completely reversed upon annealing at 300 °C, as all the defects originally observed in the reference sample were recovered. 相似文献
16.
K. K. Venter S. P. Korshunov L. I. Vereshchagin R. L. Bol'shedvorskaya D. O. Lolya S. A. Giller 《Chemistry of Heterocyclic Compounds》1966,1(4):415-416
Nitration of methyl furyl-2-propiolate in acetic anhydride at -25° gives methyl 5-nitrofuryl-2-propiolate in good yield. Methods for preparing furyl-2-propiolic acid and its methyl ester are described. 相似文献
17.
Genomics: massively parallel sequencing 总被引:1,自引:0,他引:1
18.
Extractive electrospray ionization for direct analysis of undiluted urine, milk and other complex mixtures without sample preparation 总被引:7,自引:0,他引:7
On-line droplet-droplet extraction occurs when a sample spray intersects a reagent electrospray; this allows continuous analysis of trace amounts of compounds directly in complex matrices including undiluted urine, milk and polluted water over extended periods of time. 相似文献
19.
N. Eassa R. Betz E. Coetsee H.C. Swart A. Venter J.R. Botha 《Current Applied Physics》2013,13(2):366-370
X-ray photoelectron spectroscopy, field emission scanning electron microscopy, Raman and photoluminescence spectroscopy were used to evaluate the surface properties of n-type InAs (111)A etched in a 1% Br–methanol solution. Etching completely removes the native oxides from the surface and enhances the photoluminescence response. The adsorption of bromine onto the InAs surface leads to the formation of In–Brx and As–Brx bonds (x = 1, 2, 3) as inferred from changes in the In 3d3/2;5/2 and As 3d core level binding energies. The etch rate is found to decrease due to strong anisotropic effects and the high volatility of the bromine species. A 1 min Br–methanol etch was found to enhance the photoluminescence intensity by a factor of 3, probably due to a reduction in the surface state density upon de-oxidation of the surface. This is thought to be due to reductions in the surface state density. The presence of native oxides enhances both the surface accumulation layer and the surface state density. 相似文献
20.
The FT-Raman spectrum of cupferron, [PhN2O2]NH4 and the micro-Raman spectra of the new corresponding cobalt(II) cupferronato complexes, CoL2A2, L = PhN2O2, a = H2O, MeOH, o-C6H4(NH2)2, p-C6H4(NH2)2 and CoL2A, a = (-C6H4NH2-p)2 were recorded and discussed. All the complexes show a Raman band at about 1302 cm1 and the characteristic v(N-N) and δ(ONNO) modes of the anionic ligand. the vibrational analysis of the title compounds reveals the electron delocalisation over the N-nitroso-N-hydroxylaminato (ONNO) unit, as well as the bidentate coordination of the cupferronato ligand to the metal center through the oxygen atoms. 相似文献