Watford have sacked manager Marco Silva after a poor run of recent results, the Premier League club announced on Sunday.The 40-year-old Pourtuguese leaves the Premier League side 10th in the table, but after claiming an impressive 21 points before the end of November, the Hornets have added just another five in two months.”This has been a difficult decision and one not taken lightly,” the club said in a statement on its website (www.watfordfc.com).”The Club is convinced the appointment of Silva was the right one and had it not been for the unwarranted approach by a Premier League rival for his services we would have continued to prosper under his leadership.”The catalyst for this decision is that unwarranted approach, something which the Board believes has seen a significant deterioration in both focus and results to the point where the long-term future of Watford FC has been jeopardised.”British media reported that Everton had approached Portugal’s Silva in their quest to replace Dutchman Ronald Koeman earlier this season before they appointed Sam Allardyce in November.(Source: Reuters)
This new device which is a major improvement on the earlier plasma jet devices has been developed by Mounir Laroussi and XinPei Lu at the Old Dominion University in Virginia, could be used to kill bacteria, heal wounds and treat plaque.At atmospheric pressure, most plasmas are so hot (thousands of degrees centigrade) that they would immediately kill any living cells they come into contact with. Moreover, these high-temperature plasmas are also very difficult to control. In recent years, however, researchers have developed techniques for producing low-temperature plasmas and some of these have been used in biomedical applications. However, till now the replacement were not very reliable.A good low-temperature plasma source must be able to work at room temperature and atmospheric pressure. Moreover, it should be hand-held and must not “arc” and heat up while operating. The new device developed by Laroussi and Lu consists of two electrodes, each made of a thin copper ring attached to the surface of a glass disk: the disk is about 2.5 centimetres across and has a small hole at its centre. These electrodes are then inserted into a dielectric tube and are separated by a gap that can be varied between 0.5 and 1 centimeter.When helium gas is injected into the tube and short (less than one microsecond) high-voltage pulses are applied to the electrodes, a discharge is ignited in the gap between the electrodes. This produces a plasma plume that is ejected through the hole in the outer electrode. The plume can be up to 5 centimetres long, with the length depending on the flow rate of the helium and the size of the voltage pulses. The plume remains at room temperature and can be touched by bare hands.The device is an improvement on previous plasma “jet” devices that only generate short plumes that have lengths in the millimetre range and can reach temperatures several tens of degrees above room temperature. And unlike other devices, such as the “plasma needle”, the new apparatus contains no sharp metal objects. And since very short voltage pulses are used, there is no risk of arcing and heating if the device is deployed for long periods.This development of cold plasma can have far reaching effects not only in biomedical sciences, but also in all areas where plasma are used. Its portability has added benefit. This might help the scientists and researchers use plasma in other fields.Dr. Bikram Lamba, an international management consultant, is Chairman & Managing Director of Tormacon Limited- a multi-disciplinary consultancy organization.He can be contacted at 9058484205. Email: [email protected], site: www.torconsult.com .by Dr. Bikram Lamba, Copyright 2005 PhysOrg.com Researchers have developed a new hand-held device that can produce room-temperature plasmas for diverse applications, most important for biomedical applications. Citation: Advent of Cold Plasma (2005, September 22) retrieved 18 August 2019 from https://phys.org/news/2005-09-advent-cold-plasma.html Explore further A next-generation triboelectric nanogenerator (TENG) to realize constant current from electrostatic breakdown This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
Journal information: Nature Astronomy Citation: Closer look at supernova dust suggests there’s more of it than previously assumed (2019, June 18) retrieved 18 August 2019 from https://phys.org/news/2019-06-closer-supernova-previously-assumed.html Scientists have known for some time that dust emitted by stars makes its way to our solar system. They have also known that some of that dust comes from supernovas. In this new effort, the researchers claim that they have found evidence that more of the interstellar dust that makes it to Earth comes from supernovas than previously thought.The researchers suggest that the reason less star dust was attributed to supernovas was because researchers lacked the tools to properly examine the grains of dust. They further report that the development of a Cameca NanoSIMS 50 ion probe allowed them to measure such dust in better detail. Their measurement process also included the use of an ion mass spectrometer capable of measuring isotopes with high spatial resolution. By using the new technology, the researchers determined how much of the dust came from regular stars churning away, and how much came from supernovas (less than 1 percent). The percentage that originated from supernovas was higher than expected—this suggests that more of the star dust that makes it to Earth has a supernova origin. And that suggests that more of the star dust in space originated in supernovae than has been thought.The dust studied by the researchers was obtained from chondrite samples found in Northwest Africa. Close study via the new technology allowed the researchers to measure the amount of magnesium they contained, which they also note predates our own star. They point out that most of the material in our solar system was created from material ejected from stars; thus, a better understanding of stardust could lead to a better understanding of how we got here. Explore further More information: Jan Leitner et al. A new population of dust from stellar explosions among meteoritic stardust, Nature Astronomy (2019). DOI: 10.1038/s41550-019-0788-x This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. A pair of researchers with the Max Planck Institute for Chemistry dust from a supernova have found evidence that suggests it is more abundant than thought. In their paper published in the journal Nature Astronomy, Jan Leitner and Peter Hoppe describe their use of new technology to examine grains of supernova dust and what they found. Cosmic dust forms in supernovae blasts This image shows the remnant of Supernova 1987A seen in light of very different wavelengths. ALMA data (in red) shows newly formed dust in the centre of the remnant. Hubble (in green) and Chandra (in blue) data show the expanding shock wave. Credit: ALMA/NASA © 2019 Science X Network