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101.
Mónica Denham Kerstin Wendt Germán Bianchini Ana Cortés Tomàs Margalef 《Journal of computational science》2012,3(5):398-404
This work represents the first step towards a Dynamic Data-Driven Application System (DDDAS) for wildland fire prediction. Our main efforts are focused on taking advantage of the computing power provided by High Performance Computing systems and to propose computational data-driven steering strategies to overcome input data uncertainty. In doing so, prediction quality can be enhanced significantly. On the other hand, these proposals reduce the execution time of the overall prediction process in order to be of use during real-time crisis. In particular, this work describes a Dynamic Data-Driven Genetic Algorithm (DDDGA) used as steering strategy to automatically adjust highly dynamic input data values of forest fire simulators taking into account the underlying propagation model and real fire behaviour. 相似文献
102.
Charles S. Cockell Kerstin Scherer Gerda Horneck Petra Rettberg Rainer Facius Anton Gugg-Helminger Colin Driscoll Pascal Lee 《Photochemistry and photobiology》2001,74(4):570-578
During July 2000 we used an electronic personal dosimeter (X-2000) and a biological dosimeter (Deutsches Zentrum für Luft- und Raumfahrt: Biofilm) to characterize the UV radiation exposure of arctic field scientists involved in biological and geological fieldwork. These personnel were working at the Haughton impact structure on Devon Island (75 degrees N) in the Canadian High Arctic under a 24 h photoperiod. During a typical day of field activities under a clear sky, the total daily erythemally weighted exposure, as measured by electronic dosimetry, was up to 5.8 standard erythemal dose (SED). Overcast skies (typically 7-8 okta of stratus) reduced exposures by a mean of 54%. We estimate that during a month of field activity in July a typical field scientist at this latitude could potentially receive approximately 80 SED to the face. Because of body movements the upper body was exposed to a UV regimen that often changed on second-to-second time-scales as assessed by electronic dosimetry. Over a typical 10 min period on vehicle traverse, we found that erythemal exposure could vary to up to 87% of the mean exposure. Time-integrated exposures showed that the type of outdoor field activities in the treeless expanse of the polar desert had little effect on the exposure received. Although absolute exposure changed in accordance with the time of day, the exposure ratio (dose received over horizontal dose) did not vary much over the day. Under clear skies the mean exposure ratio was 0.35 +/- 0.12 for individual activities at different times of the day assessed using electronic dosimetry. Biological dosimetry showed that the occupation was important in determining daily exposures. In our study, scientists in the field received an approximately two-fold higher dose than individuals, such as medics and computer scientists, who spent the majority of their time in tents. 相似文献
103.
In the present work we investigate the temporal development of arbitrarily distributed voids in a visco-plastic material under different loading regimes. A mesoscopic continuum model is used in order to take the microstructure of the material into account. In particular, we introduce a mesoscopic space representing an extension of the space-time domain of the continuum mechanical fields. This extended domain requires a reformulation of the classical balance equations as well as the consideration of additional constitutive quantities. Furthermore a mesoscopic distribution function can be introduced which follows an own balance. Assuming a special model of porous composites, the spherical shell model, all required steps are elaborated in order to describe load-induced void-growth in a metal-like matrix. We conclude with some exemplary results which show astonishing similarities with co-called LSW-theories. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
104.
Jacob M. Wurlitzer Aleksa Stanii Sebastian Ziethe Paul M. Jordan Kerstin Günther Oliver Werz Hajo Kries Markus Gressler 《Chemical science》2022,13(31):9091
The realm of natural products of early diverging fungi such as Mortierella species is largely unexplored. Herein, the nonribosomal peptide synthetase (NRPS) MalA catalysing the biosynthesis of the surface-active biosurfactants, malpinins, has been identified and biochemically characterised. The investigation of the substrate specificity of respective adenylation (A) domains indicated a substrate-tolerant enzyme with an unusual, inactive C-terminal NRPS module. Specificity-based precursor-directed biosynthesis yielded 20 new congeners produced by a single enzyme. Moreover, MalA incorporates artificial, click-functionalised amino acids which allowed postbiosynthetic coupling to a fluorophore. The fluorescent malpinin conjugate penetrates mammalian cell membranes via an phagocytosis-mediated mechanism, suggesting Mortierella oligopeptides as carrier peptides for directed cell targeting. The current study demonstrates substrate-specificity testing as a powerful tool to identify flexible NRPS modules and highlights basal fungi as reservoir for chemically tractable compounds in pharmaceutical applications.Specificity profiling of a nonribosomal peptide synthetase of an early diverging fungus revealed high substrate flexibility. Feeding studies with click-functionalised amino acids enabled the production of fluorescent peptides targeting macrophages. 相似文献
105.
Ruud Peters Ingrid Elbers Anna Undas Eelco Sijtsma Sophie Briffa Pauline Carnell-Morris Agnieszka Siupa Tae-Hyun Yoon Loïc Burr David Schmid Jutta Tentschert Yves Hachenberger Harald Jungnickel Andreas Luch Florian Meier Jovana Kocic Jaeseok Kim Byong Chon Park Barry Hardy Colin Johnston Kerstin Jurkschat Jrg Radnik Vasile-Dan Hodoroaba Iseult Lynch Eugenia Valsami-Jones 《Molecules (Basel, Switzerland)》2022,27(15)
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