119 research outputs found
Correction: Music listening while you learn: No influence of background music on verbal learning
BACKGROUND: Whether listening to background music enhances verbal learning performance is still disputed. In this study we investigated the influence of listening to background music on verbal learning performance and the associated brain activations.
METHODS: Musical excerpts were composed for this study to ensure that they were unknown to the subjects and designed to vary in tempo (fast vs. slow) and consonance (in-tune vs. out-of-tune). Noise was used as control stimulus. 75 subjects were randomly assigned to one of five groups and learned the presented verbal material (non-words with and without semantic connotation) with and without background music. Each group was exposed to one of five different background stimuli (in-tune fast, in-tune slow, out-of-tune fast, out-of-tune slow, and noise). As dependent variable, the number of learned words was used. In addition, event-related desynchronization (ERD) and event-related synchronization (ERS) of the EEG alpha-band were calculated as a measure for cortical activation.
RESULTS: We did not find any substantial and consistent influence of background music on verbal learning. There was neither an enhancement nor a decrease in verbal learning performance during the background stimulation conditions. We found however a stronger event-related desynchronization around 800 - 1200 ms after word presentation for the group exposed to in-tune fast music while they learned the verbal material. There was also a stronger event-related synchronization for the group exposed to out-of-tune fast music around 1600 - 2000 ms after word presentation.
CONCLUSION: Verbal learning during the exposure to different background music varying in tempo and consonance did not influence learning of verbal material. There was neither an enhancing nor a detrimental effect on verbal learning performance. The EEG data suggest that the different acoustic background conditions evoke different cortical activations. The reason for these different cortical activations is unclear. The most plausible reason is that when background music draws more attention verbal learning performance is kept constant by the recruitment of compensatory mechanisms
Evaluation of evoked potentials to dyadic tones after cochlear implantation
Auditory evoked potentials are tools widely used to assess auditory cortex functions in clinical context. However, in cochlear implant users, electrophysiological measures are challenging due to implant-created artefacts in the EEG. Here, we used independent component analysis to reduce cochlear implant-related artefacts in event-related EEGs of cochlear implant users (n = 12), which allowed detailed spatio-temporal evaluation of auditory evoked potentials by means of dipole source analysis. The present study examined hemispheric asymmetries of auditory evoked potentials to musical sounds in cochlear implant users to evaluate the effect of this type of implantation on neuronal activity. In particular, implant users were presented with two dyadic tonal intervals in an active oddball design and in a passive listening condition. Principally, the results show that independent component analysis is an efficient approach that enables the study of neurophysiological mechanisms of restored auditory function in cochlear implant users. Moreover, our data indicate altered hemispheric asymmetries for dyadic tone processing in implant users compared with listeners with normal hearing (n = 12). We conclude that the evaluation of auditory evoked potentials are of major relevance to understanding auditory cortex function after cochlear implantation and could be of substantial clinical value by indicating the maturation/reorganization of the auditory system after implantatio
Inverse modelling of two-dimensional water infiltration into a soil containing macropores
Two series of axi-symmetric laboratory infiltration experiments were carried out in homogeneous sand and in sand containing artificially made vertical macropores. In the first case the results are compared with numerical solution of the Richards equation. In the second case the results are compared with the double-porosity model obtained by homogenization. The constitutive relations between the capillary pressure, saturation and unsaturated hydraulic conductivity for the sand and macropores are identified via numerical inverse analysis of cumulative infiltration. The applicability of several types of constitutive functions available in the literature is tested. The saturated conductivity and air-entry pressure fitted for the macropores are compared with theoretical predictions. The cumulative infiltration curves fitted by numerical inversion show reasonable agreement with observations for both types of porous media
Visual activation of auditory cortex reflects maladaptive plasticity in cochlear implant users
Cross-modal reorganization in the auditory cortex has been reported in deaf individuals. However, it is not well understood whether this compensatory reorganization induced by auditory deprivation recedes once the sensation of hearing is partially restored through a cochlear implant. The current study used electroencephalography source localization to examine cross-modal reorganization in the auditory cortex of post-lingually deafened cochlear implant users. We analysed visual-evoked potentials to parametrically modulated reversing chequerboard images between cochlear implant users (nâ=â11) and normal-hearing listeners (nâ=â11). The results revealed smaller P100 amplitudes and reduced visual cortex activation in cochlear implant users compared with normal-hearing listeners. At the P100 latency, cochlear implant users also showed activation in the right auditory cortex, which was inversely related to speech recognition ability with the cochlear implant. These results confirm a visual take-over in the auditory cortex of cochlear implant users. Incomplete reversal of this deafness-induced cortical reorganization might limit clinical benefit from a cochlear implant and help explain the high inter-subject variability in auditory speech comprehensio
Safety and Efficacy of Ranibizumab in Diabetic Macular Edema (RESOLVE Study*): A 12-month, randomized, controlled, double-masked, multicenter phase II study
The expression of vascular endothelial growth factor (VEGF) is elevated in diabetic macular edema (DME). Ranibizumab binds to and inhibits multiple VEGF variants. We investigated the safety and efficacy of ranibizumab in DME involving the foveal center
Measuring star formation in high-z massive galaxies: A mid-infrared to submillimeter study of the GOODS NICMOS Survey sample
We present measurements of the mean mid-infrared-to-submillimeter flux
densities of massive (M\ast \approx 2 \times 10^11 Msun) galaxies at redshifts
1.7 < z < 2.9, obtained by stacking positions of known objects taken from the
GOODS NICMOS Survey (GNS) catalog on maps: at 24 {\mu}m (Spitzer/MIPS); 70,
100, and 160{\mu}m (Herschel/PACS); 250, 350, 500{\mu}m (BLAST); and 870{\mu}m
(LABOCA). A modified blackbody spectrum fit to the stacked flux densities
indicates a median [interquartile] star-formation rate of SFR = 63 [48, 81]
Msun yr^-1 . We note that not properly accounting for correlations between
bands when fitting stacked data can significantly bias the result. The galaxies
are divided into two groups, disk-like and spheroid-like, according to their
Sersic indices, n. We find evidence that most of the star formation is
occurring in n \leq 2 (disk-like) galaxies, with median [interquartile] SFR =
122 [100,150] Msun yr^-1, while there are indications that the n > 2
(spheroid-like) population may be forming stars at a median [interquartile] SFR
= 14 [9,20] Msun yr^-1, if at all. Finally, we show that star formation is a
plausible mechanism for size evolution in this population as a whole, but find
only marginal evidence that it is what drives the expansion of the
spheroid-like galaxies.Comment: Accepted by MNRAS. 10 pages, 3 figures, 3 table
Non-invasive Drug Monitoring of ÎČ-Lactam Antibiotics Using Sweat Analysis-A Pilot Study
Background: Antimicrobial resistance is a major challenge in treating infectious diseases. Therapeutic drug monitoring (TDM) can optimize and personalize antibiotic treatment. Previously, antibiotic concentrations in tissues were extrapolated from skin blister studies, but sweat analyses for TDM have not been conducted. Objective: To investigate the potential of sweat analysis as a non-invasive, rapid, and potential bedside TDM method. Methods: We analyzed sweat and blood samples from 13 in-house patients treated with intravenous cefepime, imipenem, or flucloxacillin. For cefepime treatment, full pharmacokinetic sampling was performed (five subsequent sweat samples every 2 h) using ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry. The ClinicalTrials.gov registration number is NCT03678142. Results: In this study, we demonstrated for the first time that flucloxacillin, imipenem, and cefepime are detectable in sweat. Antibiotic concentration changes over time demonstrated comparable (age-adjusted) dynamics in the blood and sweat of patients treated with cefepime. Patients treated with standard flucloxacillin dosage showed the highest mean antibiotic concentration in sweat. Conclusions: Our results provide a proof-of-concept that sweat analysis could potentially serve as a non-invasive, rapid, and reliable method to measure antibiotic concentration and as a surrogate marker for tissue penetration. If combined with smart biosensors, sweat analysis may potentially serve as the first lab-independent, non-invasive antibiotic TDM method
A WellâDefined Anionic Dicopper(I) Monohydride Complex that Reacts like a Cluster**
Low-nuclearity copper hydrides are rare and few well-defined dicopper hydrides have been reported. Herein, we describe the first example of a structurally characterized anionic dicopper hydride complex. This complex does not display typical reactivity associated with low-nuclearity copper hydrides, such as alcoholysis or insertion reactions. Instead, its stoichiometric and catalytic reactivity is akin to that of copper hydride clusters. The distinct reactivity is ascribed to the robust dinuclear core that is bound tightly within the dinucleating ligand scaffold
Young Stellar Objects and Triggered Star Formation in the Vulpecula OB Association
The Vulpecula OB association, VulOB1, is a region of active star formation
located in the Galactic plane at 2.3 kpc from the Sun. Previous studies suggest
that sequential star formation is propagating along this 100 pc long molecular
complex. In this paper, we use Spitzer MIPSGAL and GLIMPSE data to reconstruct
the star formation history of VulOB1, and search for signatures of past
triggering events. We make a census of Young Stellar Objects (YSO) in VulOB1
based on IR color and magnitude criteria, and we rely on the properties and
nature of these YSOs to trace recent episodes of massive star formation. We
find 856 YSO candidates, and show that the evolutionary stage of the YSO
population in VulOB1 is rather homogeneous - ruling out the scenario of
propagating star formation. We estimate the current star formation efficiency
to be ~8 %. We also report the discovery of a dozen pillar-like structures,
which are confirmed to be sites of small scale triggered star formation.Comment: 30 pages, 11 figures, accepted for publication in Ap
Modelling Galaxy and AGN Evolution in the IR: Black Hole Accretion versus Star-Formation Activity
We present a new backward evolution model for galaxies and AGNs in the
infrared (IR). What is new in this model is the separate study of the
evolutionary properties of the different IR populations (i.e. spiral galaxies,
starburst galaxies, low-luminosity AGNs, "unobscured" type 1 AGNs and
"obscured" type 2 AGNs) defined through a detailed analysis of the spectral
energy distributions (SEDs) of large samples of IR selected sources. The
evolutionary parameters have been constrained by means of all the available
observables from surveys in the mid- and far-IR (source counts, redshift and
luminosity distributions, luminosity functions). By decomposing the SEDs
representative of the three AGN classes into three distinct components (a
stellar component emitting most of its power in the optical/near-IR, an AGN
component due to hot dust heated by the central black hole peaking in the
mid-IR, and a starburst component dominating the far-IR spectrum) we have
disentangled the AGN contribution to the monochromatic and total IR luminosity
emitted by the different populations considered in our model from that due to
star-formation activity. We have then obtained an estimate of the total IR
luminosity density (and star-formation density - SFD - produced by IR galaxies)
and the first ever estimate of the black hole mass accretion density (BHAR)
from the IR. The derived evolution of the BHAR is in agreement with estimates
from X-rays, though the BHAR values we derive from IR are slightly higher than
the X-ray ones. Finally, we have simulated source counts, redshift
distributions and SFD and BHAR that we expect to obtain with the future
cosmological Surveys in the mid-/far-IR that will be performed with JWST-MIRI
and SPICA-SAFARI.Comment: 19 pages, 15 figures, 3 tables. Accepted for publication in MNRA
- âŠ