@article{Paycha2018, author = {Paycha, Sylvie}, title = {When the market wins over research and higher education}, series = {Sustainable Futures for Higher Education : the Making of Knowledge Makers}, volume = {7}, journal = {Sustainable Futures for Higher Education : the Making of Knowledge Makers}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-96035-7}, issn = {2364-6799}, doi = {10.1007/978-3-319-96035-7_2}, pages = {23 -- 28}, year = {2018}, abstract = {In this chapter, an overview of systematic eradication of basic science foci in European universities in the last two decades is given. This happens under the slogan of optimisation of the university education to the needs and demands of the society. It is pointed out that reliance on "market demands" brings with it long-term deficiencies in the maintenance of basic and advanced knowledge construction in societies necessary for long-term future technological advances. University policies that claim improvement of higher education towards more immediate efficiency may end up with the opposite effect of affecting its quality and long term expected positive impact on society.}, language = {en} } @article{ChangMahmoudiSchulze2018, author = {Chang, Der-Chen and Mahmoudi, Mahdi Hedayat and Schulze, Bert-Wolfgang}, title = {Volterra operators in the edge-calculus}, series = {Analysis and Mathematical Physics}, volume = {8}, journal = {Analysis and Mathematical Physics}, number = {4}, publisher = {Springer}, address = {Basel}, issn = {1664-2368}, doi = {10.1007/s13324-018-0238-4}, pages = {551 -- 570}, year = {2018}, abstract = {We study the Volterra property of a class of anisotropic pseudo-differential operators on R x B for a manifold B with edge Y and time-variable t. This exposition belongs to a program for studying parabolicity in such a situation. In the present consideration we establish non-smoothing elements in a subalgebra with anisotropic operator-valued symbols of Mellin type with holomorphic symbols in the complex Mellin covariable from the cone theory, where the covariable t of t extends to symbolswith respect to t to the lower complex v half-plane. The resulting space ofVolterra operators enlarges an approach of Buchholz (Parabolische Pseudodifferentialoperatoren mit operatorwertigen Symbolen. Ph. D. thesis, Universitat Potsdam, 1996) by necessary elements to a new operator algebra containing Volterra parametrices under an appropriate condition of anisotropic ellipticity. Our approach avoids some difficulty in choosing Volterra quantizations in the edge case by generalizing specific achievements from the isotropic edge-calculus, obtained by Seiler (Pseudodifferential calculus on manifolds with non-compact edges, Ph. D. thesis, University of Potsdam, 1997), see also Gil et al. (in: Demuth et al (eds) Mathematical research, vol 100. Akademic Verlag, Berlin, pp 113-137, 1997; Osaka J Math 37: 221-260, 2000).}, language = {en} } @article{KnoechelKloftHuisinga2018, author = {Kn{\"o}chel, Jane and Kloft, Charlotte and Huisinga, Wilhelm}, title = {Understanding and reducing complex systems pharmacology models based on a novel input-response index}, series = {Journal of pharmacokinetics and pharmacodynamics}, volume = {45}, journal = {Journal of pharmacokinetics and pharmacodynamics}, number = {1}, publisher = {Springer Science + Business Media B.V.}, address = {New York}, issn = {1567-567X}, doi = {10.1007/s10928-017-9561-x}, pages = {139 -- 157}, year = {2018}, abstract = {A growing understanding of complex processes in biology has led to large-scale mechanistic models of pharmacologically relevant processes. These models are increasingly used to study the response of the system to a given input or stimulus, e.g., after drug administration. Understanding the input-response relationship, however, is often a challenging task due to the complexity of the interactions between its constituents as well as the size of the models. An approach that quantifies the importance of the different constituents for a given input-output relationship and allows to reduce the dynamics to its essential features is therefore highly desirable. In this article, we present a novel state- and time-dependent quantity called the input-response index that quantifies the importance of state variables for a given input-response relationship at a particular time. It is based on the concept of time-bounded controllability and observability, and defined with respect to a reference dynamics. In application to the brown snake venom-fibrinogen (Fg) network, the input-response indices give insight into the coordinated action of specific coagulation factors and about those factors that contribute only little to the response. We demonstrate how the indices can be used to reduce large-scale models in a two-step procedure: (i) elimination of states whose dynamics have only minor impact on the input-response relationship, and (ii) proper lumping of the remaining (lower order) model. In application to the brown snake venom-fibrinogen network, this resulted in a reduction from 62 to 8 state variables in the first step, and a further reduction to 5 state variables in the second step. We further illustrate that the sequence, in which a recursive algorithm eliminates and/or lumps state variables, has an impact on the final reduced model. The input-response indices are particularly suited to determine an informed sequence, since they are based on the dynamics of the original system. In summary, the novel measure of importance provides a powerful tool for analysing the complex dynamics of large-scale systems and a means for very efficient model order reduction of nonlinear systems.}, language = {en} } @article{KleinRosenberger2018, author = {Klein, Markus and Rosenberger, Elke}, title = {Tunneling for a class of difference operators}, series = {Annales Henri Poincar{\´e} : a journal of theoretical and mathematical physics}, volume = {19}, journal = {Annales Henri Poincar{\´e} : a journal of theoretical and mathematical physics}, number = {11}, publisher = {Springer International Publishing}, address = {Cham}, issn = {1424-0637}, doi = {10.1007/s00023-018-0732-0}, pages = {3511 -- 3559}, year = {2018}, abstract = {We analyze a general class of difference operators Hε=Tε+Vε on ℓ2((εZ)d), where Vε is a multi-well potential and ε is a small parameter. We derive full asymptotic expansions of the prefactor of the exponentially small eigenvalue splitting due to interactions between two "wells" (minima) of the potential energy, i.e., for the discrete tunneling effect. We treat both the case where there is a single minimal geodesic (with respect to the natural Finsler metric induced by the leading symbol h0(x,ξ) of Hε) connecting the two minima and the case where the minimal geodesics form an ℓ+1 dimensional manifold, ℓ≥1. These results on the tunneling problem are as sharp as the classical results for the Schr{\"o}dinger operator in Helffer and Sj{\"o}strand (Commun PDE 9:337-408, 1984). Technically, our approach is pseudo-differential and we adapt techniques from Helffer and Sj{\"o}strand [Analyse semi-classique pour l'{\´e}quation de Harper (avec application {\`a} l'{\´e}quation de Schr{\"o}dinger avec champ magn{\´e}tique), M{\´e}moires de la S.M.F., 2 series, tome 34, pp 1-113, 1988)] and Helffer and Parisse (Ann Inst Henri Poincar{\´e} 60(2):147-187, 1994) to our discrete setting.}, language = {en} } @article{KongDeuberKittilaeetal.2018, author = {Kong, Xiang-Zhao and Deuber, Claudia A. and Kittil{\"a}, Anniina and Somogyv{\´a}ri, M{\´a}rk and Mikutis, Gediminas and Bayer, Peter and Stark, Wendelin J. and Saar, Martin O.}, title = {Tomographic Reservoir Imaging with DNA-Labeled Silica Nanotracers: The First Field Validation}, series = {Environmental science \& technology}, volume = {52}, journal = {Environmental science \& technology}, number = {23}, publisher = {American Chemical Society}, address = {Washington}, issn = {0013-936X}, doi = {10.1021/acs.est.8b04367}, pages = {13681 -- 13689}, year = {2018}, abstract = {This study presents the first field validation of using DNA-labeled silica nanoparticles as tracers to image subsurface reservoirs by travel time based tomography. During a field campaign in Switzerland, we performed short-pulse tracer tests under a forced hydraulic head gradient to conduct a multisource-multireceiver tracer test and tomographic inversion, determining the two-dimensional hydraulic conductivity field between two vertical wells. Together with three traditional solute dye tracers, we injected spherical silica nanotracers, encoded with synthetic DNA molecules, which are protected by a silica layer against damage due to chemicals, microorganisms, and enzymes. Temporal moment analyses of the recorded tracer concentration breakthrough curves (BTCs) indicate higher mass recovery, less mean residence time, and smaller dispersion of the DNA-labeled nanotracers, compared to solute dye tracers. Importantly, travel time based tomography, using nanotracer BTCs, yields a satisfactory hydraulic conductivity tomogram, validated by the dye tracer results and previous field investigations. These advantages of DNA-labeled nanotracers, in comparison to traditional solute dye tracers, make them well-suited for tomographic reservoir characterizations in fields such as hydrogeology, petroleum engineering, and geothermal energy, particularly with respect to resolving preferential flow paths or the heterogeneity of contact surfaces or by enabling source zone characterizations of dense nonaqueous phase liquids.}, language = {en} } @article{PathirajaAnghileriBurlandoetal.2018, author = {Pathiraja, Sahani Darschika and Anghileri, Daniela and Burlando, Paolo and Sharma, Ashish and Marshall, Lucy and Moradkhani, Hamid}, title = {Time-varying parameter models for catchments with land use change}, series = {Hydrology and earth system sciences : HESS}, volume = {22}, journal = {Hydrology and earth system sciences : HESS}, number = {5}, publisher = {Copernicus}, address = {G{\"o}ttingen}, issn = {1027-5606}, doi = {10.5194/hess-22-2903-2018}, pages = {2903 -- 2919}, year = {2018}, abstract = {Rapid population and economic growth in Southeast Asia has been accompanied by extensive land use change with consequent impacts on catchment hydrology. Modeling methodologies capable of handling changing land use conditions are therefore becoming ever more important and are receiving increasing attention from hydrologists. A recently developed data-assimilation-based framework that allows model parameters to vary through time in response to signals of change in observations is considered for a medium-sized catchment (2880 km(2)) in northern Vietnam experiencing substantial but gradual land cover change. We investigate the efficacy of the method as well as the importance of the chosen model structure in ensuring the success of a time-varying parameter method. The method was used with two lumped daily conceptual models (HBV and HyMOD) that gave good-quality streamflow predictions during pre-change conditions. Although both time-varying parameter models gave improved streamflow predictions under changed conditions compared to the time-invariant parameter model, persistent biases for low flows were apparent in the HyMOD case. It was found that HyMOD was not suited to representing the modified baseflow conditions, resulting in extreme and unrealistic time-varying parameter estimates. This work shows that the chosen model can be critical for ensuring the time-varying parameter framework successfully models streamflow under changing land cover conditions. It can also be used to determine whether land cover changes (and not just meteorological factors) contribute to the observed hydrologic changes in retrospective studies where the lack of a paired control catchment precludes such an assessment.}, language = {en} } @article{SalamatZoellerZareetal.2018, author = {Salamat, Mona and Z{\"o}ller, Gert and Zare, Mehdi and Amini, Mortaza}, title = {The maximum expected earthquake magnitudes in different future time intervals of six seismotectonic zones of Iran and its surroundings}, series = {Journal of seismology}, volume = {22}, journal = {Journal of seismology}, number = {6}, publisher = {Springer}, address = {Dordrecht}, issn = {1383-4649}, doi = {10.1007/s10950-018-9780-7}, pages = {1485 -- 1498}, year = {2018}, abstract = {One of the crucial components in seismic hazard analysis is the estimation of the maximum earthquake magnitude and associated uncertainty. In the present study, the uncertainty related to the maximum expected magnitude mu is determined in terms of confidence intervals for an imposed level of confidence. Previous work by Salamat et al. (Pure Appl Geophys 174:763-777, 2017) shows the divergence of the confidence interval of the maximum possible magnitude m(max) for high levels of confidence in six seismotectonic zones of Iran. In this work, the maximum expected earthquake magnitude mu is calculated in a predefined finite time interval and imposed level of confidence. For this, we use a conceptual model based on a doubly truncated Gutenberg-Richter law for magnitudes with constant b-value and calculate the posterior distribution of mu for the time interval T-f in future. We assume a stationary Poisson process in time and a Gutenberg-Richter relation for magnitudes. The upper bound of the magnitude confidence interval is calculated for different time intervals of 30, 50, and 100 years and imposed levels of confidence alpha = 0.5, 0.1, 0.05, and 0.01. The posterior distribution of waiting times T-f to the next earthquake with a given magnitude equal to 6.5, 7.0, and7.5 are calculated in each zone. In order to find the influence of declustering, we use the original and declustered version of the catalog. The earthquake catalog of the territory of Iran and surroundings are subdivided into six seismotectonic zones Alborz, Azerbaijan, Central Iran, Zagros, Kopet Dagh, and Makran. We assume the maximum possible magnitude m(max) = 8.5 and calculate the upper bound of the confidence interval of mu in each zone. The results indicate that for short time intervals equal to 30 and 50 years and imposed levels of confidence 1 - alpha = 0.95 and 0.90, the probability distribution of mu is around mu = 7.16-8.23 in all seismic zones.}, language = {en} } @article{KellerSchwarz2018, author = {Keller, Matthias and Schwarz, Michael}, title = {The Kazdan-Warner equation on canonically compactifiable graphs}, series = {Calculus of variations and partial differential equations}, volume = {57}, journal = {Calculus of variations and partial differential equations}, number = {2}, publisher = {Springer}, address = {Heidelberg}, issn = {0944-2669}, doi = {10.1007/s00526-018-1329-7}, pages = {18}, year = {2018}, abstract = {We study the Kazdan-Warner equation on canonically compactifiable graphs. These graphs are distinguished as analytic properties of Laplacians on these graphs carry a strong resemblance to Laplacians on open pre-compact manifolds.}, language = {en} } @article{MeraStepanenkoTarkhanov2018, author = {Mera, Azal and Stepanenko, Vitaly A. and Tarkhanov, Nikolai Nikolaevich}, title = {Successive approximation for the inhomogeneous burgers equation}, series = {Journal of Siberian Federal University : Mathematics \& Physics}, volume = {11}, journal = {Journal of Siberian Federal University : Mathematics \& Physics}, number = {4}, publisher = {Siberian Federal University}, address = {Krasnoyarsk}, issn = {1997-1397}, doi = {10.17516/1997-1397-2018-11-4-519-531}, pages = {519 -- 531}, year = {2018}, abstract = {The inhomogeneous Burgers equation is a simple form of the Navier-Stokes equations. From the analytical point of view, the inhomogeneous form is poorly studied, the complete analytical solution depending closely on the form of the nonhomogeneous term.}, language = {en} } @article{GomezHartung2018, author = {Gomez, Christophe and Hartung, Niklas}, title = {Stochastic and deterministic models for the metastatic emission process}, series = {Cancer Systems Biology}, volume = {1711}, journal = {Cancer Systems Biology}, publisher = {Humana Press Inc.}, address = {Totowa}, isbn = {978-1-4939-7493-1}, issn = {1064-3745}, doi = {10.1007/978-1-4939-7493-1_10}, pages = {193 -- 224}, year = {2018}, abstract = {Although the detection of metastases radically changes prognosis of and treatment decisions for a cancer patient, clinically undetectable micrometastases hamper a consistent classification into localized or metastatic disease. This chapter discusses mathematical modeling efforts that could help to estimate the metastatic risk in such a situation. We focus on two approaches: (1) a stochastic framework describing metastatic emission events at random times, formalized via Poisson processes, and (2) a deterministic framework describing the micrometastatic state through a size-structured density function in a partial differential equation model. Three aspects are addressed in this chapter. First, a motivation for the Poisson process framework is presented and modeling hypotheses and mechanisms are introduced. Second, we extend the Poisson model to account for secondary metastatic emission. Third, we highlight an inherent crosslink between the stochastic and deterministic frameworks and discuss its implications. For increased accessibility the chapter is split into an informal presentation of the results using a minimum of mathematical formalism and a rigorous mathematical treatment for more theoretically interested readers.}, language = {en} }