We examine the two-dimensional extension of the model of Kessler and Sander of competition between two species identical except for dispersion rates. In this class of models, the spatial inhomogeneity of reproduction rates gives rise to an implicit cost of dispersal, due to the tendency to leave favorable locations. Then, as in the Hamilton-May model with its explicit dispersal cost, the tradeo...

Given a matrix, the Null Space Problem asks for a basis of its null space having the fewest nonzeros. This problem is known to be NP-complete and even hard to approximate. The null space of a forest is the null space of its adjacency matrix. Sander and Sander (2005) and Akbari et al. (2006), independently, proved that the null space of each forest admits a {−1, 0, 1}-basis. We devise an algorit...

We generalize substructuring methods to problems for functions f : Ω → M , where Ω is a domain in R and M is a Riemannian manifold. Examples for such functions include configurations of liquid crystals, ferromagnets, and deformations of Cosserat materials. We show that a substructuring theory can be developed for such problems. While the theory looks very similar to the linear theory on a forma...

The phylotypic stage is the developmental stage at which vertebrates most resemble each other. In this study we test the plausibility of the hypotheses of Sander [1983, Development and Evolution, Cambridge University Press] and Raff [1994, Early Life on Earth, Columbia University Press; 1996, The Shape of Life, University of Chicago Press] that the phylotypic stage is conserved due to the inten...

BACKGROUND Orthopedic functional devices, are used to improve mandibular length in skeletal class II patients. However, the orthopedic functional device with the best effect to increasing the mandibular length, has not been identified before. Thus, the aim of the present investigation was to evaluate Randomized Controlled Trials (RCT), to determine the best functional appliance improving mandib...

We present a time-dependent finite element model of the human knee joint of full 3D geometric complexity together with advanced numerical algorithms needed for its simulation. The model comprises bones, cartilage and the major ligaments, while patella and menisci are still missing. Bones are modeled by linear elastic materials, cartilage by linear viscoelastic materials, and ligaments by onedim...

Modeling the chemical effects of ship exhaust in the cloud-free marine boundary layer R. von Glasow, M. G. Lawrence, R. Sander, and P. J. Crutzen Max-Planck-Institut für Chemie, Atmospheric Chemistry Division, PO Box 3060, 55020 Mainz, Germany 2 Center for Atmospheric Sciences, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093-0221, USA now at Scripp...

Alba Navarro, Guillem Clot, Cristina Royo, Pedro Jares, Anastasia Hadzidimitriou, Andreas Agathangelidis, Vasilis Bikos, Nikos Darzentas, Theodora Papadaki, Itziar Salaverria, Magda Pinyol, Xavier Puig, Jara Palomero, Maria Carmela Vegliante, Virgina Amador, Alejandra Martinez-Trillos, Lenka Stefancikova, Adrian Wiestner, Wyndham Wilson, Christiane Pott, Maria Jose Calasanz, Nicola Trim, Wendy ...