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991.
992.
Richard McClatchey Ashiq Anjum Heinz Stockinger Arshad Ali Ian Willers Michael Thomas 《Journal of Grid Computing》2007,5(1):43-64
In Grids scheduling decisions are often made on the basis of jobs being either data or computation intensive: in data intensive
situations jobs may be pushed to the data and in computation intensive situations data may be pulled to the jobs. This kind
of scheduling, in which there is no consideration of network characteristics, can lead to performance degradation in a Grid
environment and may result in large processing queues and job execution delays due to site overloads. In this paper we describe
a Data Intensive and Network Aware (DIANA) meta-scheduling approach, which takes into account data, processing power and network
characteristics when making scheduling decisions across multiple sites. Through a practical implementation on a Grid testbed,
we demonstrate that queue and execution times of data-intensive jobs can be significantly improved when we introduce our proposed
DIANA scheduler. The basic scheduling decisions are dictated by a weighting factor for each potential target location which
is a calculated function of network characteristics, processing cycles and data location and size. The job scheduler provides
a global ranking of the computing resources and then selects an optimal one on the basis of this overall access and execution
cost. The DIANA approach considers the Grid as a combination of active network elements and takes network characteristics
as a first class criterion in the scheduling decision matrix along with computations and data. The scheduler can then make
informed decisions by taking into account the changing state of the network, locality and size of the data and the pool of
available processing cycles. 相似文献
993.
Dissipation and transport of veterinary sulfonamide antibiotics after manure application to grassland in a small catchment 总被引:2,自引:0,他引:2
Stoob K Singer HP Mueller SR Schwarzenbach RP Stamm CH 《Environmental science & technology》2007,41(21):7349-7355
The heavy use of veterinary antibiotics in modern animal production causes concern about risks of spreading antibiotic resistance after manure applications to agricultural fields. We report on a field study aiming at elucidating the fate of sulfonamide (SA) antibiotics in grassland soils and their transport to surface water. Two controlled manure applications were carried out under different weather conditions. After both applications, the SA concentrations in pore water and the total soil content declined rapidly. This stage of fast decline was followed by a second one during which the SA were rather persistent. More than 15% of the SAs applied were still present in the soil 3 months after application, always exceeding 100 microg/kg topsoil. The apparent SA sorption increased strongly with time. Accordingly, the risk for SA losses to water bodies decreased within 2 weeks to very low values. In contrast to SA concentrations in the soil, losses to the brook were strongly influenced by the weather conditions after the two manure applications. The overall losses were 15 times larger (about 0.5% of applied SA) during the wet conditions of May 2003 compared to the dry conditions following the first application (March 2003). 相似文献
994.
995.
Bulk syntheses of colloids efficiently produce nanoparticles with unique and useful properties. Their integration onto surfaces is a prerequisite for exploiting these properties in practice. Ideally, the integration would be compatible with a variety of surfaces and particles, while also enabling the fabrication of large areas and arbitrarily high-accuracy patterns. Whereas printing routinely meets these demands at larger length scales, we have developed a novel printing process that enables positioning of sub-100-nm particles individually with high placement accuracy. A colloidal suspension is inked directly onto printing plates, whose wetting properties and geometry ensure that the nanoparticles only fill predefined topographical features. The dry particle assembly is subsequently printed from the plate onto plain substrates through tailored adhesion. We demonstrate that the process can create a variety of particle arrangements including lines, arrays and bitmaps, while preserving the catalytic and optical activity of the individual nanoparticles. 相似文献
996.
Julia Matena Svea Petersen Matthias Gieseke Michael Teske Martin Beyerbach Andreas Kampmann Hugo Murua Escobar Nils-Claudius Gellrich Heinz Haferkamp Ingo Nolte 《International journal of molecular sciences》2015,16(6):13287-13301
Degradable implant material for bone remodeling that corresponds to the physiological stability of bone has still not been developed. Promising degradable materials with good mechanical properties are magnesium and magnesium alloys. However, excessive gas production due to corrosion can lower the biocompatibility. In the present study we used the polymer coating polycaprolactone (PCL), intended to lower the corrosion rate of magnesium. Additionally, improvement of implant geometry can increase bone remodeling. Porous structures are known to support vessel ingrowth and thus increase osseointegration. With the selective laser melting (SLM) process, defined open porous structures can be created. Recently, highly reactive magnesium has also been processed by SLM. We performed studies with a flat magnesium layer and with porous magnesium implants coated with polymers. The SLM produced magnesium was compared with the titanium alloy TiAl6V4, as titanium is already established for the SLM-process. For testing the biocompatibility, we used primary murine osteoblasts. Results showed a reduced corrosion rate and good biocompatibility of the SLM produced magnesium with PCL coating. 相似文献
997.
Stefan Bittner Nicole Bobak Majella-Sophie Hofmann Michael K. Schuhmann Tobias Ruck Kerstin G?bel Wolfgang Brück Heinz Wiendl Sven G. Meuth 《International journal of molecular sciences》2015,16(8):16880-16896
Lymphocytes express potassium channels that regulate physiological cell functions, such as activation, proliferation and migration. Expression levels of K2P5.1 (TASK2; KCNK5) channels belonging to the family of two-pore domain potassium channels have previously been correlated to the activity of autoreactive T lymphocytes in patients with multiple sclerosis and rheumatoid arthritis. In humans, K2P5.1 channels are upregulated upon T cell stimulation and influence T cell effector functions. However, a further clinical translation of targeting K2P5.1 is currently hampered by a lack of highly selective inhibitors, making it necessary to evaluate the impact of KCNK5 in established preclinical animal disease models. We here demonstrate that K2P5.1 knockout (K2P5.1−/−) mice display no significant alterations concerning T cell cytokine production, proliferation rates, surface marker molecules or signaling pathways. In an experimental model of autoimmune neuroinflammation, K2P5.1−/− mice show a comparable disease course to wild-type animals and no major changes in the peripheral immune system or CNS compartment. A compensatory upregulation of the potassium channels K2P3.1 and KV1.3 seems to counterbalance the deletion of K2P5.1. As an alternative model mimicking autoimmune neuroinflammation, experimental autoimmune encephalomyelitis in the common marmoset has been proposed, especially for testing the efficacy of new potential drugs. Initial experiments show that K2P5.1 is functionally expressed on marmoset T lymphocytes, opening up the possibility for assessing future K2P5.1-targeting drugs. 相似文献
998.
Christian Martin Koller Rainer Hahn Beno Widrig Jürgen Ramm Szilárd Kolozsvári Jörg Paulitsch Paul Heinz Mayrhofer 《BHM Berg- und Hüttenm?nnische Monatshefte》2016,161(7):325-329
The synthesis of (Al,Cr)2O3 coatings by PVD frequently results in metastable cubic structures next to the thermodynamically stable and mechanically favourable hexagonal corundum phase. By alloying small amounts of Fe to powder-metallurgically produced Al0.7Cr0.3 targets – used to synthesise (Al,Cr)2O3 films by cathodic arc evaporation – a considerable increase of the hexagonal phase fraction is observed. Detailed transmission electron microscopy studies show that the growth of hexagonal crystallites of a solid solution (Al,Cr,Fe)2O3 can be triggered by small Cr- and Fe-enriched spherical particles, so-called droplets. In contrast, larger spherical or flat-shaped Al-rich droplets induce re-nucleation of undesired cubic film growth. Extending these studies to additional (Al,Cr)2O3 coating systems revealed similar mechanisms, albeit by far less frequent than in the case of Fe-alloyed films. Modifications of the chemical composition of the target by small amounts of dopants may reduce droplet generation and contribute to controlled coating nucleation. Therefore, the cathode surface used is compared with particles, intentionally selected from the plasma stream. 相似文献
999.
1000.