Imaging active

The results of the RREP, PET, and fMRl studies indicate common areas are activated by multiple respiratory modalities, suggesting convergent neural pathways for respiratory perception that can lead to specific respiratory sensations. The differences in brain activations with the different respiratory sensory modalities are likely due to the afferent systems activated. Each respiratory sensory modality has a unique convergent and divergent afferent input to the central nervous system and a unique temporal pattern of afferent activity. Despite well-known afferent responses to respiratory stimuli, it remains unknown which of the fMRI- and PET-imaged activated central neural structures are essential to produce specific respiratory sensations. 

The olfactory bulb activation data of Leon and Johnson was used as one of the evaluation data sets (Leon and Johnson). We used a subset comprising 2-deoxyglucose (2-DG) imaged activation patterns from 94 different odour stimuli. These spatial activation patterns were clustered in 60 different local spatial clusters. The mean activity within each such cluster was transformed to the range [0,1], whereby 94 patterns with 60 components were obtained (Marco et al. 2006). 

Carpentier AC, Constable RT, Schlosser MJ et al. (2001) Patterns of functional magnetic resonance imaging activation in association with structural lesions in the rolandic region a classification system. J Neurosurg 94 946-954 Carter LP, Gumerlock MK (1995) Steal and cerebral arteriovenous malformations. Stroke 26 2371-2372 Castel JP, Kantor G (2000) Postoperative morbidity and mortality after microsurgical exclusion of cerebral arteriove-... 

Figure 12.19 (a) Scheme of the SG/TC mode for imaging activity of catalyst spots for the HER. (b) Expected behavior of the tip current during a SG/TC long-direction scan over a catalyst spot when imaging the activity for the HER. 

Figure 12.21 (a) Scheme of the TG/SC mode for imaging activity of catalyst spots for the ORR in... 

Figure 12.22 (a) Schematic of the SEiCM feedback mode using the H /Hj couple to image activity... 

Suenaga, K., Wakabayashi, H., Koshino, M., Sato, Y.> Urita, K., lijima, S. (2007). Imaging active topological defects in carbon nanotubes. Nature Nanotechnology, 2, 358-360. 

Wipf used the SECM to initiate and image active corrosion pits on stainless steel and aluminum samples [58]. Chloride ions were produced at a tip through the reduction of trichloroacetic... 

Until a few years ago, the TG/SC mode of SECM operation was the most common way to image an enzyme that catalyzes oxygen reduction. TG/SC mode is well suited for imaging activity of surfaces with morphological features because it is relatively insensitive to changes in the tip-substrate distance [14]. The main difference between this mode and classical FB mode is that the feedback diffusion process is not required for TG/SC mode, which enables a direct measurement of activity in acidic solutions. This mode is the converse of SG/TC mode used for the anode catalysts. TG/SC mode has been applied to the study of the kinetics of oxygen reduction reaction (ORR) [14], evaluation of catalytically active nonprecious metal alloy compositions [57,58], optimization of Cu(II) biomimetics [59], thermodynamics-based design of catalysts [60], and analysis of wired enzyme architectures [61]. 

The other option in GC is SG/TC mode, which has been used successfully for imaging activity of anode catalysts such as GOx. However, in this mode, the analyte (O2) concentration is significantly altered, and large enzyme sample surface and small UME tips are needed. Moreover, the application of potential pulse to the sample in TG/SC mode is limited by capacitive charging currents, resulting in a poorly defined UME potential. To overcome these drawbacks in GC mode for imaging cathode catalyst activity, anew method called redox competition (RC) mode was developed in... 

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