TY  - JOUR
A1  - Haeussinger, Florian B.
A1  - Heinzel, Sebastian
A1  - Hahn, Tim
A1  - Schecklmann, Martin
A1  - Ehlis, Ann-Christine
A1  - Fallgatter, Andreas J.
T1  - Simulation of Near-Infrared Light Absorption Considering Individual Head and Prefrontal Cortex Anatomy: Implications for Optical Neuroimaging
JF  - PLoS ONE
N2  - Functional near-infrared spectroscopy (fNIRS) is an established optical neuroimaging method for measuring functional hemodynamic responses to infer neural activation. However, the impact of individual anatomy on the sensitivity of fNIRS measuring hemodynamics within cortical gray matter is still unknown. By means of Monte Carlo simulations and structural MRI of 23 healthy subjects (mean age: (25.0 +/- 2.8) years), we characterized the individual distribution of tissue-specific NIR-light absorption underneath 24 prefrontal fNIRS channels. We, thereby, investigated the impact of scalp-cortex distance (SCD), frontal sinus volume as well as sulcal morphology on gray matter volumes (V(gray)) traversed by NIR-light, i.e. anatomy-dependent fNIRS sensitivity. The NIR-light absorption between optodes was distributed describing a rotational ellipsoid with a mean penetration depth of (23.6 +/- 0.7) mm considering the deepest 5% of light. Of the detected photon packages scalp and bone absorbed (96.4 +/- 9: 7)% and V(gray) absorbed (3.1 +/- 1.8)% of the energy. The mean V(gray) volume (1.1 +/- 0.4)cm(3) was negatively correlated (r = - .76) with the SCD and frontal sinus volume (r = - .57) and was reduced by 41.5% in subjects with relatively large compared to small frontal sinus. Head circumference was significantly positively correlated with the mean SCD (r = .46) and the traversed frontal sinus volume (r = .43). Sulcal morphology had no significant impact on V(gray). Our findings suggest to consider individual SCD and frontal sinus volume as anatomical factors impacting fNIRS sensitivity. Head circumference may represent a practical measure to partly control for these sources of error variance.
KW  - Beer-lambert law
KW  - Adult head
KW  - Human brain
KW  - Spectroscopy fnirs
KW  - Photon migration
KW  - Propagation
KW  - Scattering
KW  - Model
KW  - Tissues
KW  - Media
Y1  - 2011
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142311
VL  - 6
IS  - 10
ER  - 
TY  - JOUR
A1  - Amthor, Matthias
A1  - Weißenseel, Sebastian
A1  - Fischer, Julian
A1  - Kamp, Martin
A1  - Schneider, Christian
A1  - Höfling, Sven
T1  - Electro-optical switching between polariton and cavity lasing in an InGaAs quantum well microcavity
N2  - We report on the condensation of microcavity exciton polaritons under optical excitation in a microcavity with four embedded InGaAs quantum wells. The polariton laser is characterized by a distinct nonlinearity in the input-output-characteristics, which is accompanied by a drop of the emission linewidth indicating temporal coherence and a characteristic persisting emission blueshift with increased particle density. The temporal coherence of the device at threshold is underlined by a characteristic drop of the second order coherence function to a value close to 1. Furthermore an external electric field is used to switch between polariton regime, polariton condensate and photon lasing.
KW  - Quantum-well, -wire and -dot devices
KW  - Scattering
KW  - stimulated
KW  - Resonators
KW  - Microcavity devices
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-111130
ER  - 
TY  - JOUR
T1  - Search for electroweak diboson production in association with a high-mass dijet system in semileptonic final states in \(pp\) collisions at √\(s\) =13 TeV with the ATLAS detector
JF  - Physical Review D
N2  - This paper reports on a search for electroweak diboson (WW/WZ/ZZ) production in association with a high-mass dijet system, using data from proton-proton collisions at a center-of-mass energy of N root s = 13 TeV. The data, corresponding to an integrated luminosity of 35.5 fb(-1), were recorded with the ATLAS detector in 2015 and 2016 at the Large Hadron Collider. The search is performed in final states in which one boson decays leptonically, and the other boson decays hadronically. The hadronically decaying W/Z boson is reconstructed as either two small-radius jets or one large-radius jet using jet substructure techniques. The electroweak production of WW/WZ/ZZ in association with two jets is measured with an observed (expected) significance of 2.7 (2.5) standard deviations, and the fiducial cross section is measured to be 45.1 +/- 8.6(stat.)(-14.6)(+15.9)(syst.) fb.
KW  - Proton-Proton Collisions
KW  - 2 Jets
KW  - Parton Distributions
KW  - Weak-Interactions
KW  - Cross-Section
KW  - High-Energies
KW  - Boson
KW  - Constraints
KW  - Scattering
KW  - Couplings
KW  - Particle accelerators
KW  - Hadron colliders
KW  - W & Z bosons
KW  - Gauge bosons
KW  - Quantum electrodynamics
KW  - Electroweak interaction
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-226877
VL  - 100
ER  -