42,196 research outputs found
Seasonal and Vertical Distributions of Planthoppers (Homoptera: Fulgoroidea) Within a Black Walnut Plantation
Information on the seasonal and vertical distributions of 34 species (eight families) of planthoppers was obtained from window trap collections in a North Carolina black walnut plantation in 15 and 1978. The most commonly collected species were Acanalonia conica (Acanaloniidael. Liburniella ornata (Delphacidae), Oliarus ecologus (Cixiidae), and O. quinquelineatus
Integrating Case-Based Reasoning with Adaptive Process Management
The need for more flexiblity of process-aware information systems (PAIS) has been discussed for several years and different approaches for adaptive process management have emerged. Only few of them provide support for both changes of individual process instances and the propagation of process type changes to a collection of related process instances. The knowledge about changes has not yet been exploited by any of these systems. To overcome this practical limitation, PAIS must capture the whole process life cycle and all kinds of changes in an integrated way. They must allow users to deviate from the predefined process in exceptional situations, and assist them in retrieving and reusing knowledge about previously performed changes. In this report we present a proof-of concept implementation of a learning adaptive PAIS. The prototype combines the ADEPT2 framework for dynamic process changes with concepts and methods provided by case-based reasoning(CBR) technology
Feynman versus Bakamjian-Thomas in Light Front Dynamics
We compare the Bakamjian-Thomas (BT) formulation of relativistic few-body
systems with light front field theories that maintain closer contact with
Feynman diagrams. We find that Feynman diagrams distinguish Melosh rotations
and other kinematical quantities belonging to various composite subsystem
frames that correspond to different loop integrals. The BT formalism knows only
the rest frame of the whole composite system, where everything is evaluated.Comment: 5 page
The interaction between stray electrostatic fields and a charged free-falling test mass
We present an experimental analysis of force noise caused by stray
electrostatic fields acting on a charged test mass inside a conducting
enclosure, a key problem for precise gravitational experiments. Measurement of
the average field that couples to test mass charge, and its fluctuations, is
performed with two independent torsion pendulum techniques, including direct
measurement of the forces caused by a change in electrostatic charge. We
analyze the problem with an improved electrostatic model that, coupled with the
experimental data, also indicates how to correctly measure and null the stray
field that interacts with test mass charge. Our measurements allow a
conservative upper limit on acceleration noise, of 2 fm/s\rthz\ for
frequencies above 0.1 mHz, for the interaction between stray fields and charge
in the LISA gravitational wave mission.Comment: Minor edits in PRL publication proces
Dimensionality effects on non-equilibrium electronic transport in Cu nanobridges
We report on non-equilibrium electronic transport through normal-metal (Cu)
nanobridges coupled to large reservoirs at low temperatures. We observe a
logarithmic temperature dependence of the zero-bias conductance, as well as a
universal scaling behavior of the differential conductance. Our results are
explained by electron-electron interactions in diffusive metals in the
zero-dimensional limit.Comment: RevTex, 4 page
Life\u27s Golden Sunset : Reverie Descriptive
https://digitalcommons.library.umaine.edu/mmb-ps/2624/thumbnail.jp
Actions of D-Ala2-D-Leu5-enkephalin and dynorphin A (1–17) on neocortical neurons in vitro
Intracellular recordings were made from neocortical neurons in vitro. Application of D-Ala2-D-Leu5-enkephalin (DADL) by different methods produced a decrease in EPSP amplitude and in the amplitude of L-glutamate-induced depolarizations without changes in membrane potential or membrane input resistance. The DADL effects were blocked by naloxone and persisted when synaptic transmission was depressed, suggesting DADL acts on postsynaptically located opiate receptors. With dynorphin A (1–17), depolarizations, hyperpolarizations, decreases and increases in EPSP were observed, but never an anti-glutamate effect
Neutron Charge Radius: Relativistic Effects and the Foldy Term
The neutron charge radius is studied within a light-front model with
different spin coupling schemes and wave functions. The cancellation of the
contributions from the Foldy term and Dirac form factor to the neutron charge
form factor is verified for large nucleon sizes and it is independent of the
detailed form of quark spin coupling and wave function. For the physical
nucleon our results for the contribution of the Dirac form factor to the
neutron radius are insensitive to the form of the wave function while they
strongly depend on the quark spin coupling scheme.Comment: 12 pages, 5 figures, Latex, Int. J. Mod. Phys.
The Microscopic Approach to Nuclear Matter and Neutron Star Matter
We review a variety of theoretical and experimental investigations aimed at
improving our knowledge of the nuclear matter equation of state. Of particular
interest are nuclear matter extreme states in terms of density and/or isospin
asymmetry. The equation of state of matter with unequal concentrations of
protons and neutrons has numerous applications. These include heavy-ion
collisions, the physics of rare, short-lived nuclei and, on a dramatically
different scale, the physics of neutron stars. The "common denominator" among
these (seemingly) very different systems is the symmetry energy, which plays a
crucial role in both the formation of the neutron skin in neutron-rich nuclei
and the radius of a neutron star (a system 18 orders of magnitude larger and 55
orders of magnitude heavier). The details of the density dependence of the
symmetry energy are not yet sufficiently constrained. Throughout this article,
our emphasis will be on the importance of adopting a microscopic approach to
the many-body problem, which we believe to be the one with true predictive
power.Comment: 56 pages, review article to appear in the International Journal of
Modern Physics
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