Variation in Lepidopteran Occurrence in Hemlock-Dominated and Deciduous-Dominated Forests of Central Appalachia

Eastern hemlock, (Tsuga canadensis Carrière, Pinaceae), is threatened with extirpation by an exotic invasive herbivore, the hemlock woolly adelgid, (Adelges tsugae Annand, Homoptera: Adelgidae). Given this threat, a broader and more detailed knowledge of the community associated with eastern hem- lock is merited. As Lepidoptera are important members of forest communities, this study was initiated to determine the relative occurrence of Lepidoptera in hemlock-dominated and deciduous-dominated habitats by evaluating abundance, species richness, temporal variation, and composition overlap. Lepidoptera were surveyed using blacklight traps from May – August 2010 at two collection sites in the Appalachian region of eastern Kentucky. The first collection site was within a forest stand dominated by mixed deciduous species, the second site possessed an overstory of eastern hemlock. Lepidoptera ≥ 20 mm in wingspan were identified and enumerated, yielding a total of 1,020 individuals of ≥ 137 species and 18 families. The total number of Lepidoptera captured in May and June was fewer than in July and August (P ≤ 0.05). The composition of the assemblage varied between collection sites as well as seasonally; 85 species were identified at the deciduous site and 107 species were identified at the hemlock site. While 27 species were recorded only at the deciduous site, 49 species were unique to the hemlock site. Of those unique to the hemlock site, five species were either detritivores or conifer specialists. These data demonstrate the importance of both deciduous and hemlock-dominated forest habitats for many species of Lepidoptera in Appalachia. Our study forms a foundation for understanding species richness patterns of Lepidoptera in hemlock forests in North America and is a useful baseline for comparisons of richness and diversity post invasion by the hemlock woolly adelgid

Numerical Solution of the Two-Dimensional Gross-Pitaevskii Equation for Trapped Interacting Atoms

We present a numerical scheme for solving the time-independent nonlinear Gross-Pitaevskii equation in two dimensions describing the Bose-Einstein condensate of trapped interacting neutral atoms at zero temperature. The trap potential is taken to be of the harmonic-oscillator type and the interaction both attractive and repulsive. The Gross-Pitaevskii equation is numerically integrated consistent with the correct boundary conditions at the origin and in the asymptotic region. Rapid convergence is obtained in all cases studied. In the attractive case there is a limit to the maximum number of atoms in the condensate.Comment: 5 pages LATEX, 3 postscript figure

Nonlinear Band Gap Transmission in Optical Waveguide Arrays

The effect of nonlinear transmission in coupled optical waveguide arrays is theoretically investigated via numerical simulations on the corresponding model equations. The realistic experimental setup is suggested injecting the beam in a single boundary waveguide, linear refractive index of which ($n_0$) is larger than one ($n$) of other identical waveguides in the array. Particularly, the effect holds if $\omega(n_0-n)/c>2Q$, where $Q$ is a linear coupling constant between array waveguides, $\omega$ is a carrier wave frequency and $c$ is a light velocity. Making numerical experiments in case of discrete nonlinear Schr\"odinger equation it is shown that the energy transfers from the boundary waveguide to the waveguide array above certain threshold intensity of the injected beam. This effect is explained by means of the creation and propagation of gap solitons in full analogy with the similar phenomenon of nonlinear supratransmission [F. Geniet, J. Leon, PRL, {\bf 89}, 134102, (2002)] in case of discrete sine-Gordon lattice.Comment: 4 pages, 6 figures. Phys. Rev. Lett. (in press

Collective excitations of atomic Bose-Einstein condensates

We apply linear-response analysis of the Gross-Pitaevskii equation to obtain the excitation frequencies of a Bose-Einstein condensate confined in a time-averaged orbiting potential trap. Our calculated values are in excellent agreement with those observed in a recent experiment.Comment: 11 pages, 2 Postscript figures, uses psbox.tex for automatic figure inclusion. More info at http://amo.phy.gasou.edu/bec.htm

Improving Cable Thinning System Productivity by Modifying Felling Phase Operations

Two methods of felling were tested in a thinning operation to determine if Scandinavian techniques in manual felling could be applied successfully in combination with a cable yarder for thinning in young stands of western hemlock and Douglas-fir. The study results suggest that manual felling productivity was much lower using the Scandinavian techniques, although subsequent yarding productivity was improved by more than 170% when compared with yarding production after conventional felling operations. Cost estimates developed during the study suggest that productivity improvements in the yarding phase reduced the cost of processed logs delivered to roadside by more than $2.50 per ton for the Scandinavian system

Two point correlations of a trapped interacting Bose gas at finite temperature

We develop a computationally tractable method for calculating correlation functions of the finite temperature trapped Bose gas that includes the effects of s-wave interactions. Our approach uses a classical field method to model the low energy modes and treats the high energy modes using a Hartree-Fock description. We present results of first and second order correlation functions, in position and momentum space, for an experimentally realistic system in the temperature range of $0.6T_c$ to $1.0T_c$. We also characterize the spatial coherence length of the system. Our theory should be applicable in the critical region where experiments are now able to measure first and second order correlations.Comment: 9 pages, 4 figure

Effects of Parenting by Lying in Childhood on Adult Lying, Internalizing Behaviors, and Relationship Quality

Parenting by lying is a phenomenon in which parents lie to their children, usually for a positive goal, and has been the subject of new parenting research. This study tested the associations between parenting by lying in childhood, lying to parents in young adulthood, and parent–child relationship quality. Secondly, we examined the mechanisms through which these constructs were all related to internalizing behaviors in young adulthood, specifically—stress, anxiety and depressive symptoms. Young adult participants between the ages of 18 and 24 (N = 206) responded to questions about parenting strategies experienced in childhood, their current adult functioning, lying to parents, and parent–child relationship quality. Results indicate that parenting by lying in childhood was significantly associated with lower quality relationships with parents during young adulthood. Additionally, we found that double mediation models (lying to parents and quality of parent–child relationships) were best fitting the data in explaining the exploratory mechanisms (indirect pathways) through which parenting by lying was associated with internalizing behaviors (stress responses, anxiety, and depressive symptoms) in young adulthood. Based on all the findings, a review of parenting by lying in childhood as a common parenting strategy, and further research is highly encouraged. Other implications are discussed