@article{DietlSchwinnDietletal.2016, author = {Dietl, Sebastian and Schwinn, Stefanie and Dietl, Susanne and Riedl, Simone and Deinlein, Frank and Rutkowski, Stefan and von Bueren, Andre O. and Krauss, J{\"u}rgen and Schweitzer, Tilmann and Vince, Giles H. and Picard, Daniel and Eyrich, Matthias and Rosenwald, Andreas and Ramaswamy, Vijay and Taylor, Michael D. and Remke, Marc and Monoranu, Camelia M. and Beilhack, Andreas and Schlegel, Paul G. and W{\"o}lfl, Matthias}, title = {MB3W1 is an orthotopic xenograft model for anaplastic medulloblastoma displaying cancer stem cell- and Group 3-properties}, series = {BMC Cancer}, volume = {16}, journal = {BMC Cancer}, number = {115}, doi = {10.1186/s12885-016-2170-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-145877}, year = {2016}, abstract = {Background Medulloblastoma is the most common malignant brain tumor in children and can be divided in different molecular subgroups. Patients whose tumor is classified as a Group 3 tumor have a dismal prognosis. However only very few tumor models are available for this subgroup. Methods We established a robust orthotopic xenograft model with a cell line derived from the malignant pleural effusions of a child suffering from a Group 3 medulloblastoma. Results Besides classical characteristics of this tumor subgroup, the cells display cancer stem cell characteristics including neurosphere formation, multilineage differentiation, CD133/CD15 expression, high ALDH-activity and high tumorigenicity in immunocompromised mice with xenografts exactly recapitulating the original tumor architecture. Conclusions This model using unmanipulated, human medulloblastoma cells will enable translational research, specifically focused on Group 3 medulloblastoma.}, language = {en} } @article{SchindeleBorzi2016, author = {Schindele, Andreas and Borz{\`i}, Alfio}, title = {Proximal Methods for Elliptic Optimal Control Problems with Sparsity Cost Functional}, series = {Applied Mathematics}, volume = {7}, journal = {Applied Mathematics}, number = {9}, doi = {10.4236/am.2016.79086}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-145850}, pages = {967-992}, year = {2016}, abstract = {First-order proximal methods that solve linear and bilinear elliptic optimal control problems with a sparsity cost functional are discussed. In particular, fast convergence of these methods is proved. For benchmarking purposes, inexact proximal schemes are compared to an inexact semismooth Newton method. Results of numerical experiments are presented to demonstrate the computational effectiveness of proximal schemes applied to infinite-dimensional elliptic optimal control problems and to validate the theoretical estimates.}, language = {en} } @article{BaierBaierSaipSchillingetal.2016, author = {Baier, Pablo A. and Baier-Saip, J{\"u}rgen A. and Schilling, Klaus and Oliveira, Jauvane C.}, title = {Simulator for Minimally Invasive Vascular Interventions: Hardware and Software}, series = {Presence}, volume = {25}, journal = {Presence}, number = {2}, issn = {1531-3263}, doi = {10.1162/PRES_a_00250}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140580}, pages = {108-128}, year = {2016}, abstract = {In the present work, a simulation system is proposed that can be used as an educational tool by physicians in training basic skills of minimally invasive vascular interventions. In order to accomplish this objective, initially the physical model of the wire proposed by Konings has been improved. As a result, a simpler and more stable method was obtained to calculate the equilibrium configuration of the wire. In addition, a geometrical method is developed to perform relaxations. It is particularly useful when the wire is hindered in the physical method because of the boundary conditions. Then a recipe is given to merge the physical and the geometrical methods, resulting in efficient relaxations. Moreover, tests have shown that the shape of the virtual wire agrees with the experiment. The proposed algorithm allows real-time executions, and furthermore, the hardware to assemble the simulator has a low cost.}, language = {en} } @article{SchuberthHenselerDijkstra2016, author = {Schuberth, Florian and Henseler, J{\"o}rg and Dijkstra, Theo K.}, title = {Partial least squares path modeling using ordinal categorical indicators}, series = {Quality \& Quantity}, journal = {Quality \& Quantity}, doi = {10.1007/s11135-016-0401-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-144016}, year = {2016}, abstract = {This article introduces a new consistent variance-based estimator called ordinal consistent partial least squares (OrdPLSc). OrdPLSc completes the family of variance-based estimators consisting of PLS, PLSc, and OrdPLS and permits to estimate structural equation models of composites and common factors if some or all indicators are measured on an ordinal categorical scale. A Monte Carlo simulation (N =500) with different population models shows that OrdPLSc provides almost unbiased estimates. If all constructs are modeled as common factors, OrdPLSc yields estimates close to those of its covariance-based counterpart, WLSMV, but is less efficient. If some constructs are modeled as composites, OrdPLSc is virtually without competition.}, language = {en} } @article{BraunschweigConstantinidisDellermannetal.2016, author = {Braunschweig, Holger and Constantinidis, Philipp and Dellermann, Theresa and Ewing, William and Fischer, Ingo and Hess, Merlin and Knight, Fergus and Rempel, Anna and Schneider, Christoph and Ullrich, Stefan and Vargas, Alfredo and Woolins, Derek}, title = {Highly Strained Heterocycles Constructed from Boron-Boron Multiple Bonds and Heavy Chalcogens}, series = {Angewandte Chemie, International Edition}, volume = {55}, journal = {Angewandte Chemie, International Edition}, number = {18}, doi = {10.1002/anie.201601691}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-138237}, pages = {5606 -- 5609}, year = {2016}, abstract = {The reactions of a diborene with elemental selenium or tellurium are shown to afford a diboraselenirane or diboratellurirane, respectively. These reactions are reminiscent of the sequestration of subvalent oxygen and nitrogen in the formation of oxiranes and aziridines; however, such reactivity is not known between alkenes and the heavy chalcogens. Although carbon is too electronegative to affect the reduction of elements with lower relative electronegativity, the highly reducing nature of the B B double bond enables reactions with Se0 and Te0. The capacity of multiple bonds between boron atoms to donate electron density is highlighted in reactions where diborynes behave as nucleophiles, attacking one of the two Te atoms of diaryltellurides, forming salts consisting of diboratellurenium cations and aryltelluride anions.}, subject = {Bor}, language = {en} } @article{BoehmScherzerKroletal.2016, author = {B{\"o}hm, Jennifer and Scherzer, S{\"o}nke and Krol, Elzbieta and Kreuzer, Ines and von Meyer, Katharina and Lorey, Christian and Mueller, Thomas D. and Shabala, Lana and Monte, Isabel and Salano, Roberto and Al-Rasheid, Khaled A. S. and Rennenberg, Heinz and Shabala, Sergey and Neher, Erwin and Hedrich, Rainer}, title = {The Venus Flytrap Dionaea muscipula Counts Prey-Induced Action Potentials to Induce Sodium Uptake}, series = {Current Biology}, volume = {26}, journal = {Current Biology}, number = {3}, doi = {10.1016/j.cub.2015.11.057}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128054}, pages = {286-295}, year = {2016}, abstract = {Carnivorous plants, such as the Venus flytrap (Dionaea muscipula), depend on an animal diet when grown in nutrient-poor soils. When an insect visits the trap and tilts the mechanosensors on the inner surface, action potentials (APs) are fired. After a moving object elicits two APs, the trap snaps shut, encaging the victim. Panicking preys repeatedly touch the trigger hairs over the subsequent hours, leading to a hermetically closed trap, which via the gland-based endocrine system is flooded by a prey-decomposing acidic enzyme cocktail. Here, we asked the question as to how many times trigger hairs have to be stimulated (e.g., now many APs are required) for the flytrap to recognize an encaged object as potential food, thus making it worthwhile activating the glands. By applying a series of trigger-hair stimulations, we found that the touch hormone jasmonic acid (JA) signaling pathway is activated after the second stimulus, while more than three APs are required to trigger an expression of genes encoding prey-degrading hydrolases, and that this expression is proportional to the number of mechanical stimulations. A decomposing animal contains a sodium load, and we have found that these sodium ions enter the capture organ via glands. We identified a flytrap sodium channel DmHKT1 as responsible for this sodium acquisition, with the number of transcripts expressed being dependent on the number of mechano-electric stimulations. Hence, the number of APs a victim triggers while trying to break out of the trap identifies the moving prey as a struggling Na+-rich animal and nutrition for the plant.}, subject = {Venusfliegenfalle}, language = {en} } @article{BrueningWehnerHausneretal.2016, author = {Br{\"u}ning, Christoph and Wehner, Johannes and Hausner, Julian and Wenzel, Michael and Engel, Volker}, title = {Exciton dynamics in perturbed vibronic molecular aggregates}, series = {Structural Dynamics}, volume = {3}, journal = {Structural Dynamics}, doi = {10.1063/1.4936127}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126085}, pages = {043201}, year = {2016}, abstract = {A site specific perturbation of a photo-excited molecular aggregate can lead to a localization of excitonic energy. We investigate this localization dynamics for laser-prepared excited states. Changing the parameters of the electric field significantly influences the exciton localization which offers the possibility for a selective control of this process. This is demonstrated for aggregates possessing a single vibrational degree of freedom per monomer unit. It is shown that the effects identified for the molecular dimer can be generalized to larger aggregates with a high density of vibronic states.}, language = {en} }