Phenology of Striped Cucumber Beetle, Squash Bug, and Squash Vine Borer on Muskmelon and Butternut Squash

Striped cucumber beetle (Acalymma vittatum), squash bug (Anasa tristis), and squash vine borer (Melittia cucurbitae) cause substantial economic losses on several cucurbit crops

Spin-Boson Hamiltonian and Optical Absorption of Molecular Dimers

An analysis of the eigenstates of a symmetry-broken spin-boson Hamiltonian is performed by computing Bloch and Husimi projections. The eigenstate analysis is combined with the calculation of absorption bands of asymmetric dimer configurations constituted by monomers with nonidentical excitation energies and optical transition matrix elements. Absorption bands with regular and irregular fine structures are obtained and related to the transition from the coexistence to a mixing of adiabatic branches in the spectrum. It is shown that correlations between spin states allow for an interpolation between absorption bands for different optical asymmetries.Comment: 15 pages, revTeX, 8 figures, accepted for publication in Phys. Rev.

Integrability and action operators in quantum Hamiltonian systems

For a (classically) integrable quantum mechanical system with two degrees of freedom, the functional dependence $\hat{H}=H_Q(\hat{J}_1,\hat{J}_2)$ of the Hamiltonian operator on the action operators is analyzed and compared with the corresponding functional relationship $H(p_1,q_1;p_2,q_2) = H_C(J_1,J_2)$ in the classical limit of that system. The former is shown to converge toward the latter in some asymptotic regime associated with the classical limit, but the convergence is, in general, non-uniform. The existence of the function $\hat{H}=H_Q(\hat{J}_1,\hat{J}_2)$ in the integrable regime of a parametric quantum system explains empirical results for the dimensionality of manifolds in parameter space on which at least two levels are degenerate. The comparative analysis is carried out for an integrable one-parameter two-spin model. Additional results presented for the (integrable) circular billiard model illuminate the same conclusions from a different angle.Comment: 9 page

Nosema bombi (Microsporidia: Nosematidae) and trypanosomatid prevalence in spring bumble bee queens (Hymenoptera: Apidae: Bombus) in Kansas

Citation: Tribodi, A., Cibils-Stewart, X., McCornack, B., & Szlanski, A. (2014). Nosema bombi (Microsporidia: Nosematidae) and Trypanosomatid Prevalence in Spring Bumble Bee Queens (Hymenoptera: Apidae: Bombus) in Kansas. Journal of the Entomological Society, 87(2), 225-233. https://doi.org/10.2317/JKES130730.1Several species of bumble bees are declining in the United States; these declining populations often show higher prevalence of Nosema bombi, a microsporidian pathogen. To date, surveys of bumble bee pathogens in the United States have only been conducted on workers and males, yet the health of a population is ultimately dependent on the success of colony-founding queens. We conducted a molecular-diagnostic survey of the prevalence of N. bombi and trypanosomatids, such as Crithidia bombi, in six species of spring queens (n  =  142) collected in 2011 and 2013 at three sites in central Kansas. Nosema bombi was found in 27% of Bombus pensylvanicus and 13% of B. auricomus but was not found in the other species sampled. Trypanosomatids were only found in B. pensylvanicus (9%) during the May 2013 sampling period. The high prevalence of N. bombi in B. pensylvanicus is consistent with other surveys for this pathogen in other castes, but the high prevalence of N. bombi in B. auricomus is a novel finding. Although the conservation status of B. auricomus has not been thoroughly assessed, two recently published surveys showed that B. auricomus were less common in portions of the species' range. Based on those findings and an oft-cited link between N. bombi prevalence and bumble bee species' decline (e.g., B. pensylvanicus) in other studies, our findings suggest B. auricomus populations in Kansas may warrant further scrutiny

Prólogo

Con mucho agrado ponemos a disposición de la comunidad científica, los artículos completos de los trabajos presentados en el VII Congreso de Ecología y Manejo de Ecosistemas Acuáticos Pampeanos (EMEAP 7), que se realizó el 19 y 20 de septiembre de 2013 organizado por las cátedras de Acuicultura y Ecología de la Facultad de Agronomía y Veterinaria de la Universidad Nacional de Río Cuarto (Argentina). En este evento, que contó con la asistencia de unos ciento sesenta investigadores y alumnos, se expusieron ciento dieciséis trabajos representando a veintiséis universidades e institutos de las provincias de Buenos Aires, La Pampa, Córdoba, San Luis, Corrientes, Entre Ríos y Salta.Facultad de Ciencias Naturales y Muse

Prólogo

Con mucho agrado ponemos a disposición de la comunidad científica, los artículos completos de los trabajos presentados en el VII Congreso de Ecología y Manejo de Ecosistemas Acuáticos Pampeanos (EMEAP 7), que se realizó el 19 y 20 de septiembre de 2013 organizado por las cátedras de Acuicultura y Ecología de la Facultad de Agronomía y Veterinaria de la Universidad Nacional de Río Cuarto (Argentina). En este evento, que contó con la asistencia de unos ciento sesenta investigadores y alumnos, se expusieron ciento dieciséis trabajos representando a veintiséis universidades e institutos de las provincias de Buenos Aires, La Pampa, Córdoba, San Luis, Corrientes, Entre Ríos y Salta.Facultad de Ciencias Naturales y Muse

CARBONIZED STARCH MICROCELLULAR FOAM-CELLULOSE FIBER COMPOSITE STRUCTURES

The production of microporous carbon foams from renewable starch microcellular foam-fiber (SMCF-Fiber) composites is described. Carbon foams are used in applications such as thermal insulation, battery electrodes, filters, fuel cells, and medical devices. SMCF-Fiber compos-ites were created from an aquagel. The water in the aquagel was exchanged with ethanol and then dried and carbonized. Higher amylose content starches and fiber contents of up to 4% improved the processability of the foam. The SMCF structure revealed agglomerates of swollen starch granules connected by a web of starch with pores in the 50-200 nanometer range. Heating the SMCF-fiber in a nitrogen atmosphere to temperatures between 350-700˚C produced carbon foams with a three-dimensional closed cell foam structure with cell diameters around 50 microns and pore walls around 1-3 microns. The stress versus strain compression data for carbonized samples displayed a linear elastic region and a plateau indicative of brittle crushing, typical of an elastic-brittle foam. The carbon foam products from these renew-able precursors are promising carbon structures with moderate strength and low density

Flow equations for Hamiltonians: Contrasting different approaches by using a numerically solvable model

To contrast different generators for flow equations for Hamiltonians and to discuss the dependence of physical quantities on unitarily equivalent, but effectively different initial Hamiltonians, a numerically solvable model is considered which is structurally similar to impurity models. By this we discuss the question of optimization for the first time. A general truncation scheme is established that produces good results for the Hamiltonian flow as well as for the operator flow. Nevertheless, it is also pointed out that a systematic and feasible scheme for the operator flow on the operator level is missing. For this, an explicit analysis of the operator flow is given for the first time. We observe that truncation of the series of the observable flow after the linear or bilinear terms does not yield satisfactory results for the entire parameter regime as - especially close to resonances - even high orders of the exact series expansion carry considerable weight.Comment: 25 pages, 10 figure