The Effects of Prescribed Burning and Microhabitat Type on Ant (Formicidae) Functional Groups and a Survey of Ants in the Dr. Howard Reynolds Nature Area (a Mixed Grass Prairie)

This project sought to understand how prescribed burning and microhabitat type impacts Kansas ant functional groups and also whether prescribed burning in different microhabitat types altered the burn’s impact on those functional groups. The Dr. Howard Reynolds Nature Trail, located in Hays, Kansas, was burned in the spring of 2019. The area consists of 2 distinct habitat types: a dry, mixed-grass dominated uphill area and a moist, densely vegetated downhill area. Pitfall trapping was conducted during the summers of the year prior to the burn (2018) and the year following the burn (2019). 15 pitfall traps were spread across each microhabitat during each year. Ants collected were categorized into functional groups, which allowed a comparison of ants with certain ecologies in response to the treatments. It was found that prescribed burning did not significantly impact the population size or richness of any of the ant functional groups found in this project. What played more of a role in their population dynamics were the conditions of the habitat that ants were collected from, such as the environmental stress factors and the presence of ant competitors in each microhabitat type. The uphill area, which was an open area with less environmental stress in the form of vegetative shade, favored highly competitive functional groups. The downhill area, which had higher environmental stress, favored the stress-tolerant and hypogaeic functional groups

Topology with Dynamical Overlap Fermions

We perform dynamical QCD simulations with $n_f=2$ overlap fermions by hybrid Monte-Carlo method on $6^4$ to $8^3\times 16$ lattices. We study the problem of topological sector changing. A new method is proposed which works without topological sector changes. We use this new method to determine the topological susceptibility at various quark masses.Comment: 15 pages, 3 figure

Mutations in SPG11, encoding spatacsin, are a major cause of spastic paraplegia with thin corpus callosum.

Autosomal recessive hereditary spastic paraplegia (ARHSP) with thin corpus callosum (TCC) is a common and clinically distinct form of familial spastic paraplegia that is linked to the SPG11 locus on chromosome 15 in most affected families. We analyzed 12 ARHSP-TCC families, refined the SPG11 candidate interval and identified ten mutations in a previously unidentified gene expressed ubiquitously in the nervous system but most prominently in the cerebellum, cerebral cortex, hippocampus and pineal gland. The mutations were either nonsense or insertions and deletions leading to a frameshift, suggesting a loss-of-function mechanism. The identification of the function of the gene will provide insight into the mechanisms leading to the degeneration of the corticospinal tract and other brain structures in this frequent form of ARHSP

Time evolution of Matrix Product States

In this work we develop several new simulation algorithms for 1D many-body quantum mechanical systems combining the Matrix Product State variational ansatz with Taylor, Pade and Arnoldi approximations to the evolution operator. By comparing all methods with previous techniques based on Trotter decompositions we demonstrate that the Arnoldi method is the best one, reaching extremely good accuracy with moderate resources. Finally we apply this algorithm to studying the formation of molecules in an optical lattices when crossing a Feschbach resonance with a cloud of two-species hard-core bosons.Comment: More extensive comparison with all nearest-neighbor spin s=1/2 models. The results in this manuscript have been superseded by a more complete work in cond-mat/061021

A Simple n-Dimensional Intrinsically Universal Quantum Cellular Automaton

We describe a simple n-dimensional quantum cellular automaton (QCA) capable of simulating all others, in that the initial configuration and the forward evolution of any n-dimensional QCA can be encoded within the initial configuration of the intrinsically universal QCA. Several steps of the intrinsically universal QCA then correspond to one step of the simulated QCA. The simulation preserves the topology in the sense that each cell of the simulated QCA is encoded as a group of adjacent cells in the universal QCA.Comment: 13 pages, 7 figures. In Proceedings of the 4th International Conference on Language and Automata Theory and Applications (LATA 2010), Lecture Notes in Computer Science (LNCS). Journal version: arXiv:0907.382