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Study of interaction of NO and (NO)2 molecules with silver clusters has been carried out using the hybrid method S2LYP based on density functional theory (DFT). The role of cluster charge and site of adsorption on N–O stretch frequency, adsorption energy and geometry has been investigated. Four cluster models of different size have been used for simulation of (NO)2 adsorption on Ag{111} surface. The pronounced effect of N–N bond shortening in comparison with gaseous (NO)2 has been found due to adsorption of (NO)2 on silver cluster. This phenomenon is important as possible pathway of N–N bond formation in catalytic fragmentation of NO molecule. The calculations showed that the silver octamer is the best candidate for simulation of formation and fragmentation of (NO)2 on Ag{111} surface within the cluster model.

In: Computing Letters

vibration frequency is involved in time dilation. Treisman et al. (1994) simulated oscillator neurons with vibration frequencies that move toward the external stimulus frequency only when the stimulus frequency is close enough to the intrinsic vibration frequency of the oscillators. However, in their

In: Timing & Time Perception

Ab initio calculations were performed to asses the aromatic behavior of mixed tetramer neutral cluster (Be2N2, Be2P2, Mg2N2, Mg2P2). Harmonic vibrational analysis has been performed to ensure the stability of the optimized geometries. The analysis of structure, vibrational frequencies, and molecular orbitals indicates that all these tetramer favor planar atomic configuration as the lowest energy structure and exhibit the characteristics of aromaticity (planarity and two π- electrons in the delocalized molecular orbital). Other than this, the aromatic character of these clusters has been verified based on established criteria of aromaticity such as chemical (extra stability), and magnetic criteria i.e. by calculating Nuclear Independent Chemical Shift (NICS) at the ring centers. The extra electronic stability of these clusters towards donating or accepting of electrons is also reflected in the calculated large ionization potential and low electron affinity

In: Computing Letters

Primary sensory areas previously thought to be devoted to a single modality can exhibit multisensory responses. Some have interpreted these responses as evidence for crossmodal recruitment (i.e., primary sensory processing for inputs in a non-primary modality); however, the direct contribution of this activity to perception is unclear. We tested the specific contributions of visual and auditory cortex to tactile perception in healthy adult volunteers using anodal transcranial direct current stimulation (tDCS). This form of non-invasive neuromodulation can enhance neural excitability and facilitate learning. In a series of psychophysical experiments we characterized participants’ ability to discriminate grating orientation or vibration frequency. We measured perceptual sensitivity before, during, and after tDCS application over either visual cortex or auditory cortex. Each participant received both anodal and sham interventions on separate sessions in counterbalanced order. We found that anodal stimulation over visual cortex selectively improved tactile spatial acuity, but not frequency sensitivity. Conversely, anodal stimulation over auditory cortex selectively improved tactile frequency sensitivity, but not spatial acuity. Furthermore, we found that improvements in tactile perception persisted after cessation of tDCS. These results reveal a clear double-dissociation in the crossmodal contributions of visual and auditory cortex to tactile perception, and support a supramodal brain organization scheme in which visual and auditory cortex comprise distributed networks that support shape and frequency perception, independent of sensory input modality.

In: Seeing and Perceiving
Author: James F. Fish

Noise Measuring Set (overall frequency response 20-20,000 Hz ± 2 db) and Magnecord Model 728-4 magnetic tape recorder (frequency response 50-12,000 Hz ± 2 db) at 19 cm/sec and graphically analyzed on a Kay Vibralyzer vibration frequency analyzer. Analyses of 25 sounds from 6 lobsters (3 males, 3 females

In: Crustaceana

has its benefits and disadvantages. Piezoelectric vibrators provide a large vibration frequency range, but the amplitude is limited to 0.1–0.2 mm (Harrington and Hunter Downs, 2001 ; Harrington et al ., 2000 ; Hashimoto et al ., 1998 ). Consequently, these vibrators are only appropriate for

In: Multisensory Research

was then removed from the tube and its mass recorded. Rattling sounds were analyzed using MacSpeechLab II (GW Instruments, Inc., Somer- ville, MA). The analysis was restricted to the periods in which the snakes seemed to exhibit maximum tail vibration frequency. Fast Fourier transformation allowed for

In: Amphibia-Reptilia

supports volunteer’s right arm by holding it at the wrist to ensure the arm is stationary. A hand-held vibrator purchased in a department store (vibration frequency approx. 90 Hz) is firmly pressed into the biceps tendon of the blindfolded volunteer. The volunteer uses her other arm to indicate the extent

In: Multisensory Research

literature on CMCs in touch is quite large, in part because the sense of touch contains multiple dimensions, including vibrational frequency, size, smoothness, softness, and elasticity. However, the vast majority of research on CMCs involving tactile dimensions has been about solid objects, a summary of

In: Multisensory Research
Authors: Anna Pecio and Jan Rafiński

the fan may play an important role in species recognition and perhaps it is relevant that T. vulgaris and T. montandoni 22 have almost identical tail vibration frequencies. Arnold (1972) claims that chemical signals are of primary importance in species recognition, unfortunately almost nothing is

In: Amphibia-Reptilia