Excitation

1. We demonstrated multisecond increases in the excitability of the rostral-scratch reflex in the turtle by electrically stimulating the shell at sites within the rostral-scratch receptive field. To examine the cellular mechanisms for these multisecond increases in scratch excitability, we recorded from single cutaneous afferents and sensory interneurons that responded to stimulation of the shell within the rostral-scratch receptive field. A single segment of the midbody spinal cord (D4, the 4th postcervical segment) was isolated in situ by transecting the spinal cord at the segment's anterior and posterior borders. The isolated segment was left attached to its peripheral nerve that innervates part of the rostral-scratch receptive field. A microsuction electrode (4-5 microns ID) was used to record extracellularly from the descending axons of cutaneous afferents and interneurons in the spinal white matter at the posterior end of the D4 segment. 2. The turtle shell is innervated b...

▪   We explore the extent to which neocortical circuits generalize, i.e., to what extent can neocortical neurons and the circuits they form be considered as canonical? We find that, as has long been suspected by cortical neuroanatomists, the same basic laminar and tangential organization of the excitatory neurons of the neocortex is evident wherever it has been sought. Similarly, the inhibitory neurons show characteristic morphology and patterns of connections throughout the neocortex. We offer a simple model of cortical processing that is consistent with the major features of cortical circuits: The superficial layer neurons within local patches of cortex, and within areas, cooperate to explore all possible interpretations of different cortical input and cooperatively select an interpretation consistent with their various cortical and subcortical inputs.

New techniques for spectroscopy in supersonic expansions and in the development of specific supersonic sources were developed, including vacuum ultraviolet absorption spectroscopy in supersonic expansions, development of conical nozzles for supersonic jets and pulse extraction mass spectrometer. Research included studies of energetics of rydberg states of jet-cooled molecules, rydberg states of anthracene, intramolecular relaxation of rydberg states and interference effects between extravalence and intravalence molecular excitations. The rotational state dependence of intramolecular dynamics was investigated as well as the coupling between intrastate vibrational energy redistribution and interstate electronic relaxation and the coriolis rotation-vibration coupling and intramolecular dynamics. Mediated intersystem crossing phenomenology, inverse isotope effects and microscopic level shifts were explored. Studies of fluorescence quantum yields for highly-excited states of large molecu...

Quantum Division The notion of quantum mechanics is that variables are expressed as integer values. In quantum fluids, for instance, vortices are quantized in terms of the polarization and phase shifts observed as multiples of 2π, that is, full rotations of each variable around the vortex core. Theoretical work has predicted that in some instances there should be half-quantum vortices, where circumventing the vortex core is characterized by just π rotations of the phase and polarization. By observing exciton-polariton condensates Lagoudakis et al. (p. 974 ) present evidence for the existence of these long-predicted half-quantum vortices.

We report a detection of the excited 220-211 rotational transition of para-H2O in APM 08279+5255 using the IRAM Plateau de Bure interferometer. At z = 3.91, this is the highest-redshift detection of interstellar water to date. From LVG modeling, we conclude that this transition is predominantly radiatively pumped and on its own does not provide a good estimate of the water abundance. However, additional water transitions are predicted to be detectable in this source, which would lead to an improved excitation model. We also present a sensitive upper limit for the HF J = 1 - 0 absorption toward APM 08279+5255. While the face-on geometry of this source is not favorable for absorption studies, the lack of HF absorption is still puzzling and may be indicative of a lower fluorine abundance at z = 3.91 compared with the Galactic ISM.

The modeling of permanent magnet synchronous motors (PMSM) through the use of a per-phase equivalent circuit presents difficulties due to permanent magnet excitation and the machine's magnetic parameter variations at high operating levels of saturation. This paper describes the development of a two-axis circuit model for PMSM by taking machine magnetic parameter variations and core loss into account. The circuit model can be applied to both surface mounted magnet and interior permanent magnet rotor configurations. A method for online parameter identification based on no-load parameters and saturation level, to improve the model, is discussed in detail. Test schemes to measure the equivalent circuit parameters and to calculate saturation constants which govern the parameter variations are also presented.

The theory for radiation emission, absorption, and transfer in a thermochemical nonequilibrium flow is presented. The expressions developed reduce correctly to the limit at equilibrium. To implement the theory in a practical computer code, some approximations are used, particularly the smearing of molecular radiation. Details of these approximations are presented and helpful information is included concerning the use of the computer code. This user's manual should benefit both occasional users of the Langley Optimized Radiative Nonequilibrium (LORAN) code and those who wish to use it to experiment with improved models or properties.