40,377 research outputs found
Further Observations on the Nesting Behavior of \u3ci\u3eLiris Argentatus\u3c/i\u3e (Hymenoptera: Sphecidae)
A three-celled nest of Liris argentatus was excavated and examined in upstate New York. The nest was constructed from the terminus of an abandoned cicada-killer burrow and the cells contained 1-4 incompletely paralyzed Gryllus pennsylvanicus as prey. Two of the three cells were cleptoparasitized by the satellite fly Senotainia trilineata. The components of the ecology and behavior of L. argentatus we observed are compared with those from previous studies on this species
A New Host Family for \u3ci\u3eLyroda Subita\u3c/i\u3e (Hymenoptera: Sphecidae)
Lyroda subita, a sphecid that ordinarily stocks its cells with Gryllidae, is reported provisioning a two-celled nest in upstate New York with Tridactylidae. The structure of the nest, depth of celis, stages of wasps, and degree of paralysis of the prey are described
Gravitational Correction to Running of Gauge Couplings
We calculate the contribution of graviton exchange to the running of gauge
couplings at lowest non-trivial order in perturbation theory. Including this
contribution in a theory that features coupling constant unification does not
upset this unification, but rather shifts the unification scale. When
extrapolated formally, the gravitational correction renders all gauge couplings
asymptotically free.Comment: 4 pages, 2 figures; v2: Clarified awkward sentences and notations.
Corrected typos. Added references and discussion thereof in introduction.
Minor copy editting changes to agree with version to be published in Physical
Review Letter
Reconstructed warm season temperatures for Nome, Seward Peninsula, Alaska
[1] Understanding of past climate variability in the Bering Strait region and adjacent land areas is limited by a paucity of long instrumental and paleoclimatic records. Here we describe a reconstruction of May - August temperatures for Nome, Seward Peninsula, Alaska based on maximum latewood density data which considerably extends the available climatic information. The reconstruction shows warm conditions in the late 1600s and middle-20th century and cooler conditions in the 1800s. The summer of 1783, coinciding with the Laki, Iceland volcanic event, is among the coldest in the reconstruction. Statistically significant relationships with the North Pacific Index and Bering-Chukchi sea surface temperatures indicate that the Seward tree-ring data are potentially useful as long-term indices of atmosphere-ocean variability in the region.</p
Birman-Schwinger and the number of Andreev states in BCS superconductors
The number of bound states due to inhomogeneities in a BCS superconductor is
usually established either by variational means or via exact solutions of
particularly simple, symmetric perturbations. Here we propose estimating the
number of sub-gap states using the Birman-Schwinger principle. We show how to
obtain upper bounds on the number of sub-gap states for small normal regions
and derive a suitable Cwikel-Lieb-Rozenblum inequality. We also estimate the
number of such states for large normal regions using high dimensional
generalizations of the Szego theorem. The method works equally well for local
inhomogeneities of the order parameter and for external potentials.Comment: Final version to appear in Phys Rev
Electrolytically regenerative hydrogen-oxygen fuel cell Patent
Electrolytically regenerative hydrogen-oxygen fuel cell
Nongassing NiCd battery cell
Method of constructing nickel cadmium batteries prevents excessive gas buildup and allows hermetic sealing of battery for increased service life and reduced maintenance cost
Dynamics after a sweep through a quantum critical point
The coherent quantum evolution of a one-dimensional many-particle system
after sweeping the Hamiltonian through a critical point is studied using a
generalized quantum Ising model containing both integrable and non-integrable
regimes. It is known from previous work that universal power laws appear in
such quantities as the mean number of excitations created by the sweep. Several
other phenomena are found that are not reflected by such averages: there are
two scaling regimes of the entanglement entropy and a relaxation that is
power-law rather than exponential. The final state of evolution after the
quench is not well characterized by any effective temperature, and the
Loschmidt echo converges algebraically to a constant for long times, with
cusplike singularities in the integrable case that are dynamically broadened by
nonintegrable perturbations.Comment: 4 pages, 4 figure
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