GSE statistics without spin

Energy levels statistics following the Gaussian Symplectic Ensemble (GSE) of Random Matrix Theory have been predicted theoretically and observed numerically in numerous quantum chaotic systems. However in all these systems there has been one unifying feature: the combination of half-integer spin and time-reversal invariance. Here we provide an alternative mechanism for obtaining GSE statistics that is based on geometric symmetries of a quantum system which alleviates the need for spin. As an example, we construct a quantum graph with a particular discrete symmetry given by the quaternion group Q8. GSE statistics is then observed within one of its subspectra.Comment: 5 pages, 6 figure

Chaotic maps and flows: Exact Riemann-Siegel lookalike for spectral fluctuations

To treat the spectral statistics of quantum maps and flows that are fully chaotic classically, we use the rigorous Riemann-Siegel lookalike available for the spectral determinant of unitary time evolution operators $F$. Concentrating on dynamics without time reversal invariance we get the exact two-point correlator of the spectral density for finite dimension $N$ of the matrix representative of $F$, as phenomenologically given by random matrix theory. In the limit $N\to\infty$ the correlator of the Gaussian unitary ensemble is recovered. Previously conjectured cancellations of contributions of pseudo-orbits with periods beyond half the Heisenberg time are shown to be implied by the Riemann-Siegel lookalike

Microwave Realization of the Gaussian Symplectic Ensemble

This work was funded by the Deutsche Forschungsgemeinschaft via the individual Grants No. STO 157/16-1 and No. KU 1525/3-1. C. H. J. acknowledges the Leverhulme Trust (Grant No. ECF-2014-448) for financial support

Semiclassical approach to discrete symmetries in quantum chaos

We use semiclassical methods to evaluate the spectral two-point correlation function of quantum chaotic systems with discrete geometrical symmetries. The energy spectra of these systems can be divided into subspectra that are associated to irreducible representations of the corresponding symmetry group. We show that for (spinless) time reversal invariant systems the statistics inside these subspectra depend on the type of irreducible representation. For real representations the spectral statistics agree with those of the Gaussian Orthogonal Ensemble (GOE) of Random Matrix Theory (RMT), whereas complex representations correspond to the Gaussian Unitary Ensemble (GUE). For systems without time reversal invariance all subspectra show GUE statistics. There are no correlations between non-degenerate subspectra. Our techniques generalize recent developments in the semiclassical approach to quantum chaos allowing one to obtain full agreement with the two-point correlation function predicted by RMT, including oscillatory contributions.Comment: 26 pages, 8 Figure

Finite pseudo orbit expansions for spectral quantities of quantum graphs

We investigate spectral quantities of quantum graphs by expanding them as sums over pseudo orbits, sets of periodic orbits. Only a finite collection of pseudo orbits which are irreducible and where the total number of bonds is less than or equal to the number of bonds of the graph appear, analogous to a cut off at half the Heisenberg time. The calculation simplifies previous approaches to pseudo orbit expansions on graphs. We formulate coefficients of the characteristic polynomial and derive a secular equation in terms of the irreducible pseudo orbits. From the secular equation, whose roots provide the graph spectrum, the zeta function is derived using the argument principle. The spectral zeta function enables quantities, such as the spectral determinant and vacuum energy, to be obtained directly as finite expansions over the set of short irreducible pseudo orbits.Comment: 23 pages, 4 figures, typos corrected, references added, vacuum energy calculation expande

1994 turfgrass research report

Moss control on bentgrass greens evaluation / Jill Taylor -- Preemergent spotted spurge broadleaf weed control evaluation / William Pound and Renee Stewart -- Finale/Roundup herbicide demonstration evaluation / William Pound and Renee Stewart -- Turflon solvent evaluation / William Pound and Renee Stewart -- General turfgrass broadleaf weed control evaluation / William Pound and Renee Stewart -- Postemergence herbicide efficacy on crabgrass / John Street and Renee Stewart -- Preemergence herbicide efficacy on crabgrass / John Street, Jill Taylor and Renee Stewart -- Leaf spot control study / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Dollar spot control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Brown patch control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Anthracnose control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Summer patch control study / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Yellow tuft control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Red thread control study, Columbus / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Red thread control study, Delaware / Joe Rimelspach, Bobby Joyner, Joe Green and Jerry Sullivan -- Susceptibility of bentgrass cultivars to Fore+ Aliette combinations / Karl Danneberger and Jill Taylor -- Suppression of turf diseases with biocontrol agent fortified compost-amended topdressings / Marcella Grebus, Carol Musselman, Joe Rimelspach and Harry Hoitink -- Evaluation of fungicides for resistance to dollar spot (Sclerotinia homoecmpa) on creeping bentgrass / Joe Rimelspach, Jill Taylor and Karl Danneberger -- Application of an insect growth regulator and insecticide on baits for control of ant mounds in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Application of insecticides for control of black turfgrass ataenius larvae in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Evaluation of biorationals and biologicals for control of black cutworm (Agrotis ipsilon Hufnagel) and sod webworm (Pyralidae, Crambinae) larvae in bentgrass, 1994 / David Shetlar, Harry Niemczyk and Kevin Power -- Evaluation of pyrethroids and other insecticides for control of black cutworm (Agrotis ipsilon Hufnagel) and sod webworm (Pyralidae, Crambinae) larvae in bentgrass, 1994 / David Shetlar, Harry Niemczyk and Kevin Power -- Surface and subsurface applied insecticides for control of white grubs in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Influence of application time on the efficacy of insect growth regulators for control of white grubs in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Subsurface placement of controlled release chlorpyrifos granules for extended control of Japanese beetle larvae in turfgrass: third report / Harry Niemczyk and David Shetlar -- Evaluation of Turplex 3 % EC for control of black cutworm larvae on the greens of Shadow Creek Golf Course, N. Las Vegas, Nevada / Harry Niemczyk -- Nitrogen Source and Rate effect on Kentucky bluegrass / John Street and Renee Stewart -- Polymer-coated nitrogen source effect on Kentucky bluegrass / John Street and Renee Stewart -- Evaluation of turfgrass species and cultivars for shade / Jill Taylor -- Regional low input sustainable turf study / Jill Taylor -- 1990 NTEP perennial ryegrass test / Jill Taylor -- 1994 NTEP perennial ryegrass test / Jill Taylor -- 1993 NTEP bentgrass test (fairway/tee) / Jill Taylor -- 1993 NTEP fineleaf fescue test / Jill Taylor -- Bermudagrass management study / John Street and Jill Taylor -- Duration of rolling as measured by ball roll / Karl Danneberger, Jill Taylor and Jobin Morrow -- Golf ball roll as influenced by soft spike and traditional metal spike golf shoes / Karl Danneberger and Jobin Morrow -- Primo/Banner interaction study / Bill Pound, Renee Stewart and Joe Rimelspach -- Primo growth regulator evaluation on creeping bentgrass / William Pound and Renee Stewart -- Restriction of arbitrary amplification fragments of Poa annua L. / Patty Sweeney and Karl Danneberge

Aging in females is associated with changes in respiratory modulation of sympathetic nerve activity and blood pressure

Sympathetic nerve activity (SNA) is tightly coupled with the respiratory cycle. In healthy human males, respiratory modulation of SNA does not change with age. However, it is unclear how this modulation is affected by age in females. We investigated whether respiratory sympathetic modulation is altered in healthy postmenopausal (PMF) versus premenopausal female (YF), and younger male (YM) adults, and determined its relationship to resting blood pressure. Muscle SNA (MSNA; microneurography), respiration (transducer belt), ECG, and continuous blood pressure were measured in 12 YF, 13 PMF, and 12 YM healthy volunteers. Respiratory modulation of MSNA was quantified during two phases of the respiratory cycle: mid-late expiration and inspiration/postinspiration. All groups showed respiratory modulation of MSNA (P < 0.0005). There was an interaction between the respiratory phase and group for MSNA [bursts/100 heartbeats (HB) (P ¼ 0.004) and bursts/min (P ¼ 0.029)], with smaller reductions in MSNA during inspiration observed in PMF versus the other groups. Respiratory modulation of blood pressure was also reduced in PMF versus YF (6 [2] vs. 12 [9] mmHg, P ¼ 0.008) and YM (13 [13] mmHg, P ¼ 0.001, median [interquartile range]). The magnitude of respiratory sympathetic modulation was related to resting blood pressure in PMF only, such that individuals with less modulation had greater resting blood pressure. The data indicate that aging in postmenopausal females is associated with less inspiratory inhibition of MSNA. This correlated with a higher resting blood pressure in PMF only. Thus, the reduced modulation of MSNA could contribute to the age-related rise in blood pressure that occurs in females. NEW & NOTEWORTHY The current study demonstrates that respiratory modulation of sympathetic nerve activity (SNA) is reduced in healthy postmenopausal (PMF) versus premenopausal females (YF). Furthermore, respiratory sympathetic modulation was negatively related to resting blood pressure in postmenopausal females, such that blood pressure was greater in individual with less modulation. Reduced respiratory sympathetic modulation may have implications for the autonomic control of blood pressure in aging postmenopausal females, by contributing to age-related sympathetic activation and reducing acute, respiratory-linked blood pressure variation