Ventricular myocytes deficient in endothelial nitric oxide synthase (NOS3(-/-)) exhibit prolonged action potential (AP) duration and enhanced spontaneous activity (early and delayed afterdepolarizations) during β-adrenergic (β-AR) stimulation. Studies have shown that nitric oxide is able to regulate various K(+) channels. Our objective was to examine if NOS3(-/-) myocytes had altered K(+) curre...

The effects of the phytoestrogens phloretin and phloridzin on Ca(2+) handling, cell shortening, the action potential, and Ca(2+) and K(+) currents in freshly isolated cardiac myocytes from rat ventricle were examined. Phloretin increased the amplitude and area and decreased the rate of decline of electrically evoked Ca(2+) transients in the myocytes. These effects were accompanied by an increas...

This work proposes a hybrid space vector modulation (HSVM) scheme for multiport converters (MHCs). Moreover, the impact of shifting auxiliary currents from main ones is proposed and investigated in order to enhance converter efficiency. The operational schemes have been implemented three-phase 5 kW MHC prototype. It shown that HSVM can improve efficiency by 0.3% at full load with respect modula...

in the current engineering practices, buildings are commonly designed for an effective lifetime of 50 years. this lifetime can increase the cost of buildings with short lifetimes and can reduce the safety level of buildings with large lifetimes. in this paper, a “service-life factor” has been defined. applying this factor into the nominal values of live, earthquake, wind, and snow loads, the ef...

In this paper the active device for a class E amplifier is modelled as switch in series with a turn on resistance ‘Ron’. Assuming an ideal harmonic load is used the switch equations for the voltage and current waveforms are reviewed and then used to examine how ‘Ron’ affects the efficiency of dc to ac power conversion. This ideal harmonic network is assumed to have optimum input impedance at th...

Geomagnetically Induced Currents (GIC) are supposed to be a threat to power transformers worldwide. Recent surveys show correlation between solar storm activities, the cause of GIC, and transformers failing within a relatively short time period. The scope of this contribution is to create and investigate a laboratory setup emulating GIC effects by injecting DC currents into a three phase power ...

submerged breakwaters are one of the shore protective structures. any discontinuity in these breakwaters causes changes on current parameters including speed and water surface profile. in this paper, discontinuous submerged breakwaters were modelled to investigate the changes in the wave and flow pattern.to investigate the phenomenon, three models including a shore with constant slope, a shore ...

In order to solve parameter fluctuations and disturbances, a novel fractional model reference adaptive speed observer that estimates the rotor position angular velocity from stator currents is proposed for sensorless control of permanent-magnet synchronous motors (PMSM). Firstly, controller (FOMRAC) identification designed achieve fast response high precise load torque in full range when motor ...

The goal of this study was to determine the effects of the L-type calcium channel blockers verapamil and diltiazem on the currents of voltage-gated potassium channel (fKv1.4ΔN), an N-terminal-deleted mutant of the ferret Kv1.4 potassium channel. Measurements were made using a two electrode voltage clamp technique with channels expressed stably in Xenopus oocytes. The fKv1.4ΔN currents displayed...

Hybrid stepper motors (HSMs) are commonly used in many cost-sensitive industrial and consumer applications. With the use of micro-stepping techniques, they could theoretically achieve a very high resolution in positioning of mechanical loads, even without position sensors. However, it is well known that HSMs are affected by a large torque ripple, due to cogging and phase unbalancing. This, in t...