Cellular localization of the potassium channel Kir7.1 in guinea pig and human kidney

Cellular localization of the potassium channel Kir7.1 in guinea pig and human kidney.BackgroundK+ channels have important functions in the kidney, such as maintenance of the membrane potential, volume regulation, recirculation, and secretion of potassium ions. The aim of this study was to obtain more information on the localization and possible functional role of the inwardly rectifying K+ channel, Kir7.1.MethodsKir7.1 cDNA (1114 bp) was isolated from guinea pig kidney (gpKir7.1), and its tissue distribution was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR). In addition, a genomic DNA fragment (6153 bp) was isolated from a genomic library. cRNA was expressed in Xenopus laevis oocytes for functional studies. Immunohistochemistry and RT-PCR were used to localize Kir7.1 in guinea pig and human kidney.ResultsThe expression of gpKir7.1 in Xenopus laevis oocytes revealed inwardly rectifying K+ currents. The reversal potential was strongly dependent on the extracellular K+ concentration, shifting from -14 mV at 96 mmol/L K+ to -90 mV at 1 mmol/L K+. gpKir7.1 showed a low affinity for Ba2+. Significant expression of gpKir7.1 was found in brain, kidney, and lung, but not in heart, skeletal muscle, liver, or spleen. Immunocytochemical detection in guinea pig identified the gpKir7.1 protein in the basolateral membrane of epithelial cells of the proximal tubule. RT-PCR analysis identified strong gpKir7.1 expression in the proximal tubule and weak expression in glomeruli and thick ascending limb. In isolated human tubule fragments, RT-PCR showed expression in proximal tubule and thick ascending limb.ConclusionOur results suggest that Kir7.1 may contribute to basolateral K+ recycling in the proximal tubule and in the thick ascending limb

Flamingo: Test zum sinnentnehmenden Lesen

Pilotstudie eines Tests zum sinnentnehmenden Lesen in Integrationskurses mit Alphabetisierungsschwerpunk

Modelling Energy Demand Response Using Long-Short Term Memory Neural Networks

We propose a method for detecting and forecasting events of high energy demand, which are managed at the national level in demand side response programmes, such as the UK Triads. The methodology consists of two stages: load forecasting with long short-term memory neural network and dynamic filtering of the potential highest electricity demand peaks by using the exponential moving average. The methodology is validated on real data of a UK building management system case study. We demonstrate successful forecasts of Triad events with RRMSE ≈ 2.2% and MAPE ≈ 1.6% and general applicability of the methodology for demand side response programme management, with reduction of energy consumption and indirect carbon emissions

Determination of power flow and loss allocation using superposition theory method

This paper discussed a method to determine power flow and loss from individual generator to particular load and line flows for transmission open access. Based on solved load flow, the method uses basic circuit theories including equivalent impedance, equivalent current injection and superposition theory as a foundation of algorithm's development. IEEE 14-bus test system and 4-bus test system were used to illustrate the veracity and effectiveness of the method. Comparison of the results with previous methods is also given

Power flow and loss allocation using superposition theory method for deregulated transmission system

The loss allocation of each line, which is produced by each generator, can also be obtained. Test results show that the proposed method can satisfy the power flow equation, the power balance equation and the basic circuit theories

Entwurf, Bau und Erprobung eines Prototyps zum Absaugen von Oelverschmutzungen im Meer. Phase 2: Detailkonstruktion

Wegen der zunehmenden Oelverschmutzungen der Weltmeere ist die Entwicklung technischer Loesungen zum Abschoepfen des ausgelaufenen Oels dringend geboten. Da die bisher verfuegbaren Geraete in ihrer Leistung sehr begrenzt und fuer den Einsatz im offenen Meer ungeeignet sind, wird das Krupp-Geraet, das sich bereits in vielen Faellen im sogenannten ''Glattwasserbereich'' hervorragend bewaehrt hat, fuer den Offshore-Einsatz weiterentwickelt. Mit Funktionsmodellen wurden umfangreiche Seegangs- und Oelabschoepfversuche im Wellenkanal durchgefuehrt. Dabei konnte die Funktionstuechtigkeit der erarbeiteten Geraetekonzeption unter Beibehaltung der prinzipiellen Wirkungsweise demonstriert werden. Danach konnte mit der Detailkonstruktion des Prototyps begonnen werden. Mit der Detailkonstruktion ist der Nachweis fuer die technische Realisierbarkeit des Krupp-Geraetes fuer den Offshore-Einsatz erbracht. Wegen der im Vergleich zu Spezialschiffen um mehr als eine Groessenordnung geringeren Investitionskosten besteht die Moeglichkeit, viele Standorte mit einer derartigen Oelwehrausruestung zu versehen und damit die Sicherheit der kuestennahen Regionen gegenueber Oelverschmutzungen entscheidend zu erhoehen. (orig./HS)Due to the increasing oil spill of the oceans the development of technical solutions for the absorption of the spilled oil is highly advisable. Since the performance of the equipment has been very limited so far and since they are not suitable for an application in the open sea, the Krupp equipment which proved fully up to the mark in many experiments in the so-called smooth water range, has been further developed for the offshore application. Numerous experiments concerning the oil absorption in a rough sea were carried out with functional models in the wave channel. The operativity of the developed equipment could be proved while maintaining the principal functions. Then the detailed construction of the prototype could begin. This detailed construction proves that the Krupp equipment can be technically realised for the offshore application. Due to the considerably lower investment costs in comparison to special ships such an oil weir equipment can be set up at many locations and hence the protection of coastal waters against oil spills can be considerably increased. (orig./HS)SIGLEAvailable from TIB Hannover: RN 3212(1981,54) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman