Nitrogen oxide and nitrogen dioxide gases in the upper stratosphere climbed to their highest levels in at least two decades in spring 2004, scientists report. The increases led to ozone reductions of up to 60 percent, roughly 40 kilometers [25 miles] above Earth’s high northern latitudes, according to Cora Randall of University of Colorado at Boulder and 10 colleagues in Canada, Norway, Sweden, and the United States. Two natural processes were responsible, they say.
"This decline was completely unexpected," Randall said. "The findings point out a critical need to better understand the processes occurring in the ozone layer." Randall, a researcher at the university’s Laboratory for Atmospheric and Space Physics, is lead author of a paper on the subject scheduled for publication 2 March in Geophysical Research Letters. She and her international team studied data from seven different satellites, concluding that both the Sun and stratospheric weather were responsible for the ozone declines.
Winds in the upper part of a massive winter low-pressure system, which confines air over the Arctic region and is known as the polar stratospheric vortex, sped up in February and March 2004 to become the strongest on record, she said. The spinning vortex allowed the nitrogen gases, thought to have formed at least 30 kilometers [20 miles] above the stratosphere as a result of chemical reactions triggered by energetic particles from the Sun, to descend more easily into the stratosphere.
Harvey Leifert | AGU
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Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
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At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
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Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.
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UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration
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Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.
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16.01.2017 | Power and Electrical Engineering