Source analysis of bimodal event-related potentials with auditory-visual stimuli

Dipole source analysis is applied to model brain generators of surface-recorded evoked potentials, epileptiform activity, and event-related potentials (ERP). The aim of this study was to explore brain activity of interaction between bimodal sensory cognition. Seven healthy volunteers were recruited in the study and ERP to these stimuli were recorded by 64 electrodes EEG recording system. Subjects were exposed to either the auditory and the visual stimulus alone or the combined auditory-visual (AV) stimuli. The identification of brain areas of the EP was realized using CURRY 6.0 software. A source localization analysis was performed across conditions over initial, early and later temporal stages (i.e. 3 stimuli conditions × 3 temporal stages). The source locations across conditions were contrasted over similar time periods, indicating that source location of the bimodal auditory-visual (AV) stimuli differed from the sum of source locations from the auditory and the visual stimulus alone. These data provide evidence that there exists interplay in the brain in the bimodal auditory-visual stimuli paradigm. © 2013 IEEE.published_or_final_versio

Widely adaptable oil-in-water gel emulsions stabilized by an amphiphilic hydrogelator derived from dehydroabietic acid

A surfactant, R-6-AO, derived from dehydroabietic acid has been synthesized. It behaves as a highly efficient low-molecular-weight hydrogelator with an extremely low critical gelation concentration (CGC) of 0.18 wt % (4 mm). R-6-AO not only stabilizes oil-in-water (O/W) emulsions at concentrations above its critical micelle concentration (cmc) of 0.6 mm, but also forms gel emulsions at concentrations beyond the CGC with the oil volume fraction freely adjustable between 2 % and 95 %. Cryo-TEM images reveal that R-6-AO molecules self-assemble into left-handed helical fibers with cross-sectional diameters of about 10 nm in pure water, which can be turned to very stable hydrogels at concentrations above the CGC. The gel emulsions stabilized by R-6-AO can be prepared with different oils (n-dodecane, n-decane, n-octane, soybean oil, olive oil, tricaprylin) owing to the tricyclic diterpene hydrophobic structure in their molecules that enables them to adopt a unique arrangement in the fibers

Glocal integrity in 420 stainless steel by asynchronous laser processing

Cold working individual layers during additive manufacturing (AM) by mechanical surface treatments, such as peening, effectively “prints” an aggregate surface integrity that is referred to as a glocal (i.e., local with global implications) integrity. Printing a complex, pre-designed glocal integrity throughout the build volume is a feasible approach to improve functional performance while mitigating distortion. However, coupling peening with AM introduces new manufacturing challenges, namely thermal cancellation, whereby heat relaxes favorable residual stresses and work hardening when printing on a peened layer. Thus, this work investigates glocal integrity formation from cyclically coupling LENS® with laser peening on 420 stainless steel

Lignin First: Confirming the Role of the Metal Catalyst in Reductive Fractionation

Rhodium nanoparticles embedded on the interior of hollow porous carbon nanospheres, able to sieve monomers from polymers, were used to confirm the precise role of metal catalysts in the reductive catalytic fractionation of lignin. The study provides clear evidence that the primary function of the metal catalyst is to hydrogenate monomeric lignin fragments into more stable forms following a solvent-based fractionation and fragmentation of lignin

Fabrication of hyperbranched polyamine functionalized graphene for high-efficiency removal of Pb(II) and methylene blue

© 2015 Elsevier B.V. Multifunctional hyperbranched polyamine modified graphene oxide (HPA-GO) was successfully prepared and characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), zeta potential and scanning electron microscope (SEM) analyses. HPA-GO exhibited excellent adsorption performance for the removal of a heavy metal (Pb(II)) and a dye (methylene blue (MB)). The equilibrium adsorption capacity was 819.7 mg g-1 for Pb(II) and 740.7 mg g-1 for MB under the optimal conditions. The pseudo-second order equation and the Langmuir model exhibited good correlation with the adsorption kinetic and isotherm data, respectively, for these two pollutants. The thermodynamic results (ΔG0, ΔS>0) implied that the adsorption process of Pb(II) and MB was feasible, endothermic and spontaneous in nature. A possible adsorption mechanism has been proposed where chelation and electrostatic attraction dominated the adsorption of Pb(II) and π-π stacking interactions and electrostatic attraction dominated the adsorption of MB. In addition, the excellent reproducibility endowed HPA-GO with the potential for application in water treatment

Quantum master equation approach to quantum transport through mesoscopic systems

For quantum transport through mesoscopic system, a quantum master equation approach is developed in terms of compact expressions for the transport current and the reduced density matrix of the system. The present work is an extension of Gurvitz's approach for quantum transport and quantum measurement, namely, to finite temperature and arbitrary bias voltage. Our derivation starts from a second-order cummulant expansion of the tunneling Hamiltonian, then follows conditional average over the electrode reservoir states. As a consequence, in the usual weak tunneling regime, the established formalism is applicable for a wide range of transport problems. The validity of the formalism and its convenience in application are well illustrated by a number of examples.Comment: 8 pages, 1 figure; with considerable extension of the previous version submitted in September 2004; to appear in Phys. Rev.

Enhancement of Quantum Sensing in a Cavity Optomechanical System around Quantum Critical Point

The precision of quantum sensing could be improved by exploiting quantum phase transitions, where the physical quantity tends to diverge when the system is approaching the quantum critical point. This critical enhancement phenomenon has been applied to the quantum Rabi model in a dynamic framework, showing a promising sensing enhancement without the complex initial state preparation. In this work, we find a quantum phase transition in the coupling cavity-mechanical oscillator system when the coupling strength crosses a critical point, determined by the effective detuning of cavity and frequency of mechanical mode. By utilizing this critical phenomenon, we obtain a prominent enhancement of quantum sensing, such as the position and momentum of the mechanical oscillator. This result provides an alternative method to enhance the quantum sensing of some physical quantities, such as mass, charge, and weak force, in a large mass system

Electronic structure of Fe1.04(Te0.66Se0.34)

We report the electronic structure of the iron-chalcogenide superconductor, Fe1.04(Te0.66Se0.34), obtained with high resolution angle-resolved photoemission spectroscopy and density functional calculations. In photoemission measurements, various photon energies and polarizations are exploited to study the Fermi surface topology and symmetry properties of the bands. The measured band structure and their symmetry characters qualitatively agree with our density function theory calculations of Fe(Te0.66Se0.34), although the band structure is renormalized by about a factor of three. We find that the electronic structures of this iron-chalcogenides and the iron-pnictides have many aspects in common, however, significant differences exist near the Gamma-point. For Fe1.04(Te0.66Se0.34), there are clearly separated three bands with distinct even or odd symmetry that cross the Fermi energy (EF) near the zone center, which contribute to three hole-like Fermi surfaces. Especially, both experiments and calculations show a hole-like elliptical Fermi surface at the zone center. Moreover, no sign of spin density wave was observed in the electronic structure and susceptibility measurements of this compound.Comment: 7 pages, 9 figures. submitted to PRB on November 15, 2009, and accepted on January 6, 201

A genome-wide association study identifies FSHR rs2300441 associated with follicle-stimulating hormone levels

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) play critical roles in female reproduction, while the underlying genetic basis is poorly understood. Genome-wide association studies (GWASs) of FSH and LH levels were conducted in 2590 Chinese females including 1882 polycystic ovary syndrome (PCOS) cases and 708 controls. GWAS for FSH level identified multiple variants at FSHR showing genome-wide significance with the top variant (rs2300441) located in the intron of FSHR. The A allele of rs2300441 led to a reduced level of FSH in the PCOS group (β = −.43, P = 6.70 × 10−14) as well as in the control group (β = −.35, P = 6.52 × 10−4). In the combined sample, this association was enhanced after adjusting for the PCOS status (before: β = −.38, P = 1.77 × 10−13; after: β = −.42, P = 3.33 × 10−16), suggesting the genetic effect is independent of the PCOS status. The rs2300441 explained sevenfold higher proportion of the FSH variance than the total variance explained by the two previously reported FSHR missense variants (rs2300441 R2 = 1.40% vs rs6166 R2 = 0.17%, rs6165 R2 = 0.03%). GWAS for LH did not identify any genome-wide significant associations. In conclusion, we identified genome-wide significant association between variants in FSHR and circulating FSH first, with the top associated variant rs2300441 might be a primary contributor at the population level