Little is known about how gap junctions are involved in the respiratory-related or other types of physiological neuronal activity since physiologically active gap junction currents (GJCs) have never been characterized from single respiratory-related neurons or from single neurons of any other types. In the present study we hypothesized that GJCs could be selectively revealed from single neurons...

Voltage-gated K+ channels contain a central pore domain and four surrounding voltage-sensing domains. How and where changes in the structure of the voltage-sensing domains couple to the pore domain so as to gate ion conduction is not understood. The crystal structure of KcsA, a bacterial K+ channel homologous to the pore domain of voltage-gated K+ channels, provides a starting point for address...

Voltage-gated ion channels possess charged domains that move in response to changes in transmembrane voltage. How this movement is transduced into gating of the channel pore is largely unknown. Here we show directly that two functionally important regions of the spHCN1 pacemaker channel, the S4-S5 linker and the C-linker, come into close proximity during gating. Cross-linking these regions with...

Voltage-dependent K+ channels consist of a voltage-sensing region and a pore-forming region. Here we have identified the negative residues of the second transmembrane segment in the plant voltage-dependent K+ channel, KAT1, which involves the function of voltage sensing. Point mutations at D95 and D105 but not D89 and D116 failed to complement the K+ uptake deficient properties of the mutant ye...

The measurement, quantitative analysis, theory, and mathematical modeling of transmembrane potential and currents have been an integral part of the field of electrophysiology since its inception. Biophysical modeling of action potential propagation begins with detailed ionic current models for a patch of membrane within a distributed cable model. Voltage-clamp techniques have revolutionized cli...

The present article is the fourth in a series of 6 documents focused on providing current guidelines for the standardization and interpretation of the electrocardiogram (ECG). The project was initiated by the Council on Clinical Cardiology of the American Heart Association. The rationale for this project and the process for its implementation were described earlier.1 Abnormalities in the ST seg...

Accurate determination of the pull-in, or the collapse voltage is critical in the design process. In this paper an analytical method is presented that provides a more accurate determination of the pull-in voltage for MEMS capacitive devices with clamped square diaphragm. The method incorporates both the linearized modle of the electrostatic force and the nonlinear deflection model of a clamped ...

With the development of critical loads, power quality problem has become particularly important and poor power quality will be cause many adverse effects and the cost of many deaths will follow. To improve power quality and protection of sensitive loads against grid disturbances have been used new equipment based on power electronics similar FACTs devices, they are Custom Power. One of the most...

Membrane-embedded voltage-sensor domains in voltage-dependent potassium channels (K(v) channels) contain an impressive number of charged residues. How can such highly charged protein domains be efficiently inserted into biological membranes? In the plant K(v) channel KAT1, the S2, S3, and S4 transmembrane helices insert cooperatively, because the S3, S4, and S3-S4 segments do not have any membr...