Perfusion of the renal medulla plays an important role in salt and water balance. Pericytes are smooth muscle-like cells that impart contractile function to descending vasa recta (DVR), the arteriolar segments that supply the medulla with blood flow. DVR contraction by ANG II is mediated by depolarization resulting from an increase in plasma membrane Cl(-) conductance that secondarily gates vol...

We tested whether chronic ANG II infusion into rats affects descending vasa recta (DVR) contractility, synthesis of superoxide, or synthesis of nitric oxide (NO). Rats were infused with ANG II at 250 ng.kg(-1).min(-1) for 11-13 days. DVR were loaded with dihydroethidium (DHE) to measure superoxide and 3-amino-4-aminomethyl-2',7'-difluorofluorescein (DAFFM) to measure NO. Acute constriction of D...

In this paper the effectiveness of a Dynamic Voltage Restorer controlled by neural network for voltage sags/swells mitigation is shown. A typical configuration of DVR is implemented by using MATLAB Simulink®, which is controlled using backpropagation neural networks. The good performance for voltage sags/swells mitigation of the DVR controlled with neural networks can be observed by means of se...

Several techniques of varying efficiency are investigated, which treat all singularities present in the triatomic vibrational kinetic energy operator given in orthogonal internal coordinates of the two distances-one angle type. The strategies are based on the use of a direct-product basis built from one-dimensional discrete variable representation (DVR) bases corresponding to the two distances ...

This paper proposes the designing of regional compensation type Dynamic Voltage Restorer(DVR), and the topology of main circuit, the detection algorithm for voltage sag, the calculation method of reference voltage and pulse modulation method. Based on the different load types of the target substation and the sensitivity to voltage sags, the selection principle of the location of compensation li...

Power quality has been an issue that is becoming increasingly pivotal in industrial electricity consumers point of view in recent times. Modern industries employ Sensitive power electronic equipments, control devices and non-linear loads as part of automated processes to increase energy efficiency and productivity. Voltage disturbances are the most common power quality problem due to this incre...

A new technique presents to improve the performance of dynamic voltage restorer (DVR) for voltage sag mitigation. This control scheme is based on cuckoo search algorithm with tree fuzzy rule based classifier (CSA-TFRC). CSA is used for optimizing the output of TFRC so the classification output of the network is enhanced. While, the combination of cuckoo search algorithm, fuzzy and decision tree...

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...

The dynamic voltage restorer (DVR) provides a technically advanced and economical solution to voltage-sag problem. As the voltage-restoration process involves real-power injection into the distribution system, the capability of a particular DVR topology, especially for compensating long-duration voltage sags, depends on the energy storage capacity of the DVR. The interline DVR (IDVR) proposed i...

We examined gap junction coupling of descending vasa recta (DVR). DVR endothelial cells or pericytes were depolarized to record the associated capacitance transients. Virtually all endothelia and some pericytes exhibited prolonged transients lasting 10-30 ms. Carbenoxolone (100 microM) and 18beta-glycyrrhetinic acid (18betaGRA; 100 microM) markedly shortened the endothelial transients. Carbenox...