1/f  noise in bistable electrocatalytic reactions on mesoscale electrodes.

Faraday Discuss

Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé, UMR 7515 of CNRS-Université de Strasbourg-ECPM, 25 rue Becquerel, 67087 Strasbourg, France.

Published: November 2016

The formation of a self-organized spatial domain during current-controlled CO oxidation, a kinetically bistable reaction, is investigated experimentally and by deterministic simulations as a function of the electrode size and of the supporting electrolyte concentration. Decreasing the microelectrode size leads to the suppression of the spatial instability at the electrode and thus stabilizes the S-NDR branch of the reaction. The critical microelectrode size capable of supporting sustained domain formation is shown to be strongly affected by the sulfuric acid concentration, the characteristic time of the positive feedback loop increasing with the sulfate concentration. Furthermore, we demonstrate that for microelectrode diameters close to the instability threshold, small amplitude electrochemical potential fluctuations appear in the system. These potential fluctuations cannot be captured by deterministic mathematical models and are attributed to a strong enhancement of molecular fluctuations or intrinsic noise in the vicinity of the spatial instability. Analysis of the electrochemical noise revealed a 1/f  frequency dependence and several common features with neuronal shot noise.

Download full-text PDF

Source
http://dx.doi.org/10.1039/c6fd00115gDOI Listing

Publication Analysis

Top Keywords

microelectrode size
8
spatial instability
8
potential fluctuations
8
1/f  noise
4
noise bistable
4
bistable electrocatalytic
4
electrocatalytic reactions
4
reactions mesoscale
4
mesoscale electrodes
4
electrodes formation
4

Similar Publications

Background: Glycolic acid (GA) is an α-hydroxy peeling agent that causes controlled removal of the epidermis, with or without the dermis. Studies have shown the ability of GA to stimulate fibroblast proliferation, induce collagen synthesis, and decrease collagen degradation. The VoluDerm radiofrequency microneedling (RFMN; Pollogen, Tel Aviv, Israel) utilizes an array of microelectrodes to penetrate the epidermis and deliver energy to the skin.

View Article and Find Full Text PDF

Gamma rhythm (30-70 Hz), thought to represent the interactions between excitatory and inhibitory populations, can be induced by presenting achromatic gratings in the primary visual cortex (V1) and is sensitive to stimulus properties such as size and contrast. In addition, gamma occurs in short bursts, and shows a "frequency-falloff" effect where its peak frequency is high after stimulus onset and slowly decreases to a steady state. Recently, these size-contrast properties and temporal characteristics were replicated in a self-oscillating Wilson-Cowan (WC) model operating as an Inhibition stabilized network (ISN), stimulated by Ornstein-Uhlenbeck (OU)-type inputs.

View Article and Find Full Text PDF

Understanding patterns of cortico-cortical connections in both frequently and infrequently studied species advances our knowledge of cortical organization and evolution. The agouti (Dasyprocta aguti, a medium-size South American rodent) offers a unique opportunity, because of its large lissencephalic brain and its natural behaviors, such as gnawing and hiding seeds, that require bimanual interaction while sitting on its hindlimbs and aligning its head to receive images of the horizon on the retinal visual streak. There have been no previous studies of the intrinsic and extrinsic ipsilateral projections of the agouti's primary somatosensory cortical area (S1).

View Article and Find Full Text PDF

Extracellular vesicles (EVs) are small lipid vesicles shed by cells, carrying proteins, nucleic acids, and other molecular fingerprints. EVs have emerged as crucial mediators of cell-to-cell communication and hold great promise as biomarkers for liquid biopsies, enabling disease screening, diagnosis, prognosis, and monitoring. However, conventional EV separation methods are hampered by the presence of lipoproteins (LPs) in plasma samples, which have comparable characteristics and significantly outnumber EVs.

View Article and Find Full Text PDF

Introduction: Glucose Transporter 1-Deficiency Syndrome (GLUT1-DS) is a rare genetic disorder caused by mutations in the gene encoding for GLUT1 and characterized by impaired glucose uptake in the brain. This leads to brain hypometabolism and the development of symptoms that include epilepsy, motor dysfunctions and cognitive impairment. The development of patient-specific models is a valuable tool for understanding the pathophysiology of rare genetic disorders and testing new therapeutic interventions.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!