By flowing atmospheric pressure air through a direct current powered microhollow cathode discharge, we were able to generate a 2 cm long plasma jet. With increasing flow rate, the flow becomes turbulent and temperatures of the jet are reduced to values close to room temperature. Utilizing the jet, yeast grown on agar can be eradicated with a treatment of only a few seconds. Conversely, animal studies show no skin damage even with exposures ten times longer than needed for pathogen extermination. This cold plasma jet provides an effective mode of treatment for yeast infections of the skin.

The change in the membrane potential of Jurkat cells in response to nanosecond pulsed electric fields was studied for pulses with a duration of 60 ns and maximum field strengths of approximately 100 kV/cm (100 V/cell diameter). Membranes of Jurkat cells were stained with a fast voltage-sensitive dye, ANNINE-6, which has a subnanosecond voltage response time. A temporal resolution of 5 ns was achieved by the excitation of this dye with a tunable laser pulse. The laser pulse was synchronized with the applied electric field to record images at times before, during, and after exposure. When exposing the Jurkat cells to a pulse, the voltage across the membrane at the anodic pole of the cell reached values of 1.6 V after 15 ns, almost twice the voltage level generally required for electroporation. Voltages across the membrane on the side facing the cathode reached values of only 0.6 V in the same time period, indicating a strong asymmetry in conduction mechanisms in the membranes of the two opposite cell hemispheres. This small voltage drop of 0.6-1.6 V across the plasma membrane demonstrates that nearly the entire imposed electric field of 10 V/mum penetrates into the interior of the cell and every organelle.

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Compared with the rest of the population, older people receive inequitable care for faecal incontinence. Good care improves symptoms and minimises the effects of this common problem on quality of life. Faecal incontinence is a symptom rather than a diagnosis and there are a number of options for investigation and treatment depending on the suspected underlying cause. Although there are clear guidelines for assessment and management, there are significant gaps in the evidence base and in service provision. There are many opportunities for improving care and nurses should be encouraging, supporting and leading these improvements.

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Fuel-flexible hydrogen generation methods, such as electrochemical conversion of biomass, offer a route for sustainable production of hydrogen whilst valorising feedstocks that are often overlooked as waste products. This work...

The charging of mammalian cell plasma membranes in response to ultrashort pulsed electric fields of 60 ns and field strengths up to 100 kV/cm was investigated. Membranes of Jurkat cells were stained with a potential-sensitive dye, Annine-6 and placed in a microreactor mounted on an inverted fluorescence microscope. Images of changes in the fluorescence intensity during the exposure were recorded with a high-sensitivity CCD-camera. A temporal resolution of 5 ns was achieved by illuminating the cells with a 5 ns laser pulse from a dye-laser. The laser pulse was synchronized with the high voltage pulse to record images at specific times before, during and after exposure to the electric field. When exposing Jurkat cells to a 60 ns, 100 kV/cm pulse, each hemisphere of the plasma membrane (as oriented with respect to the electrodes) responded uniquely to the applied field. From these observations it is possible to draw conclusions on the charging time of the membrane, maximum transmembrane voltages and the onset of poration.