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University of Technology of Compiègne, France

Zhao J.,Fudan University | Zhang X.,Fudan University | Wang X.,Fudan University | Deng Y.,Tsinghua University | Fu X.,University of Goettingen
Proceedings - IEEE INFOCOM | Year: 2011

As the physical link speeds grow and the size of routing table continues to increase, IP address lookup has been a challenging problem at routers. There have been growing demands in achieving high-performance IP lookup cost-effectively. Existing approaches typically resort to specialized hardwares, such as TCAM. While these approaches can take advantage of hardware parallelism to achieve high-performance IP lookup, they also have the disadvantage of high cost. This paper investigates a new way to build a cost-effective IP lookup scheme using graphics processor units (GPU). Our contribution here is to design a practical architecture for high-performance IP lookup engine with GPU, and to develop efficient algorithms for routing prefix update operations such as deletion, insertion, and modification. Leveraging GPU's many-core parallelism, the proposed schemes addressed the challenges in designing IP lookup at GPU-based software routers. Our experimental results on real-world route traces show promising gains in IP lookup and update operations. © 2011 IEEE. Source


Kilias A.,Aristotle University of Thessaloniki | Frisch W.,University of Tuebingen | Avgerinas A.,Aristotle University of Thessaloniki | Dunkl I.,University of Goettingen | And 2 more authors.
Austrian Journal of Earth Sciences | Year: 2010

Geological mapping and detailed structural investigations combined with geochronological and stratigraphic data, as well as fissiontrack age dating carried out on the northern part of the Pelagonian basement and the adjacent Vardar/Axios sedimentary and metamorphic sequences in the Hellenic Alps (northwestern Greece and Former Yugoslavian Republic of Macedonia) allow us to reconstruct the geometry, kinematics and deformation history of the Pelagonian nappe pile during the Alpine orogeny. We distinguish seven deformational events (D Hp and D 1 to D 6). Deformation started in Middle to Late Jurassic time and was associated with inneroceanic P thrusting, ophiolite obduction, and NW to WNW-directed nappe stacking of the Lower and Upper Pelagonian unit (D 1). The lower unit was metamorphosed under greenschist to amphibolite facies conditions with relatively high pressures (T=450-620°C, P=8-12,5 kb). Blueschist-facies metamorphic assemblages (D HP, T=450-500°C, P>12,5 kb) are restricted to the boundary zone between both Pelagonian units. Transgressive Late Jurassic to Early Cretaceous shallow-water limestones and clastic sediments on top of the obducted ophiolites are probably related to extension and basin formation simultaneously with nappe stacking and metamorphism in the Pelagonian nappes beneath. Contractional tectonics with the same kinematics as during D 1 continued in Aptian-Albian time and was asso-1 ciated with intense retrogression (D 2, T=280-380°C, P=4-5 kb). Low-angle mylonitic extensional shear zones of low-grade metamorphism with top-to-NE sense of movement (D 3) developed simultaneously with basin formation and sedimentation of shallow-water limestones and flysch-like sediments in Late Cretaceous to Paleocene times. Intense imbrication under semi-ductile to brittle conditions of all tectonic units occurred during Paleocene to Eocene time with SW-directed movement towards the foreland (D 4). A large Pelagonian antiformal structure formed during D 4 shortening. In Oligocene to recent time, D 5 and D 6 created brittle low and highangle normal faults, respectively. Source


News Article
Site: http://www.biosciencetechnology.com/rss-feeds/all/rss.xml/all

Scientists have deleted nearly half the genes of a microbe, creating a stripped-down version that still functions, an achievement that might reveal secrets of how life works. It may also help researchers create new bacteria tailored for pumping out medicines and other valuable substances. The newly created bacterium has a smaller genetic code than does any natural free-living counterpart, with 531,000 DNA building blocks containing 473 genes. (Humans have more than 3 billion building blocks and more than 20,000 genes). But even this stripped-down organism is full of mystery. Scientists say they have little to no idea what a third of its genes actually do. "We're showing how complex life is, even in the simplest of organisms," researcher J. Craig Venter told reporters. "These findings are very humbling." Some of the mystery genes may be clues to discovering unknown fundamental processes of life, his colleague Clyde Hutchison III said in an interview. Both researchers, from the J. Craig Venter Institute in La Jolla, California, are among the authors of a paper on the project released Thursday by the journal Science. The DNA code, or genome, is contained in a brand-new bacterium dubbed JCVI-syn3.0. The genome is not some one-and-only minimal set of genes needed for life itself. For one thing, if the researchers had pared DNA from a different bacterium they would probably have ended up with a different set of genes. For another, the minimum genome an organism needs depends on the environment in which it lives. And the new genome includes genes that are not absolutely essential to life, because they help the bacterial populations grow fast enough to be practical for lab work. The genome is "as small as we can get it and still have an organism that is ... useful," Hutchison said. One goal of such work is to understand what each gene in a living cell does, which would lead to a deep understanding of how cells work, he said. With the new bacterium, "we're closer to that than we are for any other cell," he said. Another goal is to use such minimal-DNA microbes as a chassis for adding genes to make the organisms produce medicines, fuels and other substances for uses like nutrition and agriculture, said study co-author Daniel Gibson of Synthetic Genomics in La Jolla. The work began with a manmade version of a microbe that normally lives in sheep, called M. mycoides (my-KOY'-deez). It has about 900 genes. The scientists identified 428 nonessential genes, built their new genome without them, and showed that it was complete enough to let a bacterium survive. Experts not involved with the work were impressed. "I find this paper really ground breaking," said Jorg Stulke of the University of Goettingen in Germany, who is working on a similar project with a different bacterium. In an email, he said the researchers seem to have gotten at least very close to a minimum genome for M. mycoides. Farren Isaacs of Yale University called the work "an impressive tour de force," one that may begin to identify "a universe of minimal genomes."


News Article
Site: http://phys.org/biology-news/

It may also help researchers create new bacteria tailored for making medicines and other valuable substances. The newly created bacterium has a smaller genetic code than does any natural free-living counterpart, with 531,000 DNA building blocks containing 473 genes. (Humans have more than 3 billion building blocks and more than 20,000 genes). But even this stripped-down organism is full of mystery. Scientists say they have little to no idea what a third of its genes actually do. "We're showing how complex life is, even in the simplest of organisms," researcher J. Craig Venter told reporters. "These findings are very humbling." Some of the mystery genes may be clues to discovering unknown fundamental processes of life, his colleague Clyde Hutchison III said in an interview. Both researchers, from the J. Craig Venter Institute, are among the authors of a paper on the project released Thursday by the journal Science. The DNA code, or genome, is contained in a brand-new bacterium dubbed JCVI-syn3.0. The genome is not some one-and-only minimal set of genes needed for life itself. For one thing, if the researchers had pared DNA from a different bacterium they would probably have ended up with a different set of genes. For another, the minimum genome an organism needs depends on the environment in which it lives. And the new genome includes genes that are not absolutely essential to life, because they help the bacterial populations grow fast enough to be practical for lab work. The genome is "as small as we can get it and still have an organism that is ... useful," Hutchison said. One goal of such work is to understand what each gene in a living cell does, which would lead to a deep understanding of how cells work, he said. With the new bacterium, "we're closer to that than we are for any other cell," he said. Another goal is to use such minimal-DNA microbes as a chassis for adding genes to make the organisms produce medicines, fuels and other substances for uses like nutrition and agriculture, said study co-author Daniel Gibson of Synthetic Genomics. The work began with a manmade version of a microbe that normally lives in sheep, called M. mycoides (my-KOY'-deez). It has about 900 genes. The scientists identified 428 nonessential genes, built their new genome without them, and showed that it was complete enough to let a bacterium survive. Experts not involved with the work were impressed. "I find this paper really groundbreaking," said Jorg Stulke of the University of Goettingen in Germany, who is working on a similar project with a different bacterium. In an email, he said the researchers seem to have gotten at least very close to a minimum genome for M. mycoides. Ferren Isaacs of Yale University called the work "an impressive tour de force," one that may begin to identify "a universe of minimal genomes." Explore further: First 'synthetic life': Scientists 'boot up' a bacterial cell with a synthetic genome More information: "Design and synthesis of a minimal bacterial genome," Science, DOI: 10.1126/science.aad6253


Hernandez V.H.,University Medical Center Goettingen | Hernandez V.H.,University of Goettingen | Hernandez V.H.,University of Guanajuato | Gehrt A.,University Medical Center Goettingen | And 7 more authors.
Journal of Visualized Experiments | Year: 2014

Cochlear implants (CIs) enable hearing by direct electrical stimulation of the auditory nerve. However, poor frequency and intensity resolution limits the quality of hearing with CIs. Here we describe optogenetic stimulation of the auditory nerve in mice as an alternative strategy for auditory research and developing future CIs. © JoVE 2006-2014. All Rights Reserved. Source

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