Aims The cardiac ryanodine receptor (RyR) Ca2þ release channel homotetramer harbours 21 potentially redox-sensitive cysteine residues on each subunit and may act as a sensor for reactive oxygen species (ROS), linking ROS homeostasis to the regulation of Ca2þ signalling. In cardiac myocytes, arrayed RyRs or Ca2þ release units are packed in the close proximity of mitochondria, the primary source ...

Calcium sparks in cardiac myocytes are brief, localized calcium releases from the sarcoplasmic reticulum (SR) believed to be caused by locally regenerative calcium-induced calcium release (CICR) via couplons, clusters of ryanodine receptors (RyRs). How such regeneration is terminated is uncertain. We performed numerical simulations of an idealized stochastic model of spark production, assuming ...

The spark advance determines the efficiency of spark-ignited (SI) engines by positioning the combustion in relation to the piston motion. Today’s spark-advance controllers are open-loop systems that measure parameters that effect the sparkadvance setting and compensate for their effects. Several parameters influence the best spark-advance setting but it would be too expensive to measure and acc...

The paper aims to analyze the factors affecting parameters of surge protection devices with a spark gap and assess impact changing these on level overhead line strength. For this purpose, contains results tests that show assessment voltage–time characteristics selected in range negative positive polarity. presents how change component element device, which is gap, may affect selection method. I...

High current intense electron beams were investigated earlier for Flash X-rays and nuclear electromagnetic pulse generation. Starting with moderate parameters of 200 kV, 6 kA, 60 ns pulsed electron beam source from a system named Kilo Ampere Linear Injector (KALI-75) our latest development is KALI-30 GW system rated for 1 MV, 30 kA, 80 ns. First repetitive pulse LINAC without spark gap switchin...

We present the results from a new diagnostic tool for investigating the effects of ignition on the discharge symmetry in gas-fed pulsed plasma thrusters (GFPPTs). Using a fast-framing camera, up to 16 individual pictures of a single GFPPT discharge can be captured at frequencies as high as 20 MHz. This high framing rate capability allows the discharge initiation and current sheet formation to b...

Transitive consistency is an intrinsic property for collections of linear invertible transformations between Euclidean coordinate frames. In practice, when the transformations are estimated from data, this property is lacking. This work addresses the problem of synchronizing transformations that are not transitively consistent. Once the transformations have been synchronized, they satisfy the t...

medicine has come a long way from spark gap generators 1 , electrocautery 2 and electrosurgery 3 . High-frequency radio surgery is one of the most important and Abstract High frequency radiosurgery is one of the most important and versatile tools in dentistry in present age. It can be used in various oral surgical procedures, and also useful in establishing hemostasis. Its main advantage over o...

This paper will highlight the contributions of Heinrich Hertz by his sensational experiments, carried out in Karlsruhe, Germany, in the years 1885 to 1889, to the first radio communication experiments. Heinrich Hertz developed for the first time a complete pulsed radar, an indoor communication link and a material test set, all in one. The basic system components had been the spark gap oscillato...

Excitation of 10-GHz gigawatt-range radiation pulses ~ 1 ns long in relativistic backward-wave oscillators with an elongated periodic slow-wave system has been studied. Accelerators based on a compact pulsed-periodic high-voltage generator type SINUS-160 and a generator employing an inductive energy storage, a semiconductor opening switch and a peaking hydrogen-filled spark gap have been develo...