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Microwave spectra of the propiolic acid-formic acid doubly hydrogen bonded complex were measured in the 1 GHz to 21 GHz range using four different Fourier transform spectrometers. Rotational spectra for seven isotopologues were obtained. For the parent isotopologue, a total of 138 a-dipole transitions and 28 b-dipole transitions were measured for which the a-dipole transitions exhibited splittings of a few MHz into pairs of lines and the b-type dipole transitions were split by ∼580 MHz. The transitions assigned to this complex were fit to obtain rotational and distortion constants for both tunneling levels: A0+ = 6005.289(8), B0+ = 930.553(8), C0+ = 803.9948(6) MHz, Δ0+J = 0.075(1), Δ0+JK = 0.71(1), and δ0+j = -0.010(1) kHz and A0- = 6005.275(8), B0- = 930.546(8), C0- = 803.9907(5) MHz, Δ0-J = 0.076(1), Δ0-JK = 0.70(2), and δ0-j = -0.008(1) kHz. Double resonance experiments were used on some transitions to verify assignments and to obtain splittings for cases when the b-dipole transitions were difficult to measure. The experimental difference in energy between the two tunneling states is 291.428(5) MHz for proton-proton exchange and 3.35(2) MHz for the deuterium-deuterium exchange. The vibration-rotation coupling constant between the two levels, Fab, is 120.7(2) MHz for the proton-proton exchange. With one deuterium atom substituted in either of the hydrogen-bonding protons, the tunneling splittings were not observed for a-dipole transitions, supporting the assignment of the splitting to the concerted proton tunneling motion. The spectra were obtained using three Flygare-Balle type spectrometers and one chirped-pulse machine at the University of Virginia. Rotational constants and centrifugal distortion constants were obtained for HCOOH···HOOCCCH, H13COOH···HOOCCCH, HCOOD···HOOCCCH, HCOOH···DOOCCCH, HCOOD···DOOCCCH, DCOOH···HOOCCCH, and DCOOD···HOOCCCH. High-level ab initio calculations provided initial rotational constants for the complex, structural parameters, and some details of the proton tunneling potential energy surface. A least squares fit to the isotopic data reveals a planar structure that is slightly asymmetric in the OH distances. The formic OH···O propiolic hydrogen bond length is 1.8 Å and the propiolic OH···O formic hydrogen bond length is 1.6 Å, for the equilibrium configuration. The magnitude of the dipole moment was experimentally determined to be 1.95(3) × 10-30 C m (0.584(8) D) for the 0+ states and 1.92(5) × 10-30 C m (0.576(14) D) for the 0- states. [ABSTRACT FROM AUTHOR]

In evolving toward the postindustrial society there is increasing need for the development of conceptual models based on system theoretic principles. Identification and measurement of system inputs, the dynamic behavior of identifiable subsystems, the appreciation of stochastic factors and overall system behavior are important not only to our political and professional social system managers, but also more generally to everyone in society. Our implicit aim is to plan for and to control the system so as to perform in a socially good way. However there remain major difficulties caused by the lack of data on which evaluations of societal functions can be based, and the limitations of existing system methodologies to deal with the full range of complexity in societal systems. In this paper the relationship between general systems theory and social systems is explored, including an introduction to the general system characteristics which seem basic to social systems. Emphasis is placed on the discussion of social indicators and social accounts in the system theoretic context, and the adaptibility of system and control concepts to the social environment. [ABSTRACT FROM AUTHOR]

The sound-pressure transformation of the pinna and the ear canal of the guinea pig has been measured in the frequency range 1-15 kHz. Below 1 kHz, the outer ear does not cause any significant modification in sound pressure. Between 3 and 10 kHz, the pinna provides a boost in pressure which can specifically be attributed to resonance in the concha. This boost, however, is dependent on the location of the sound source with respect to the pinna. The largest amplification is obtained when the speaker is pointed directly into the entrance of the ear canal. The acoustic behavior of the ear canal of the guinea pig is similiar to that of a rigid circular cylinder, open at both ends, about 9 mm long and 2.5 mm in diameter. The pressure transformation between the eardrum and the entrance to the ear canal is strongly dependent on the loading effect of the middle ear. Thus, experimentally induced changes in the impedance of the middle ear, and natural changes due to disease alter the sound transmission across the eardrum of this animal. In normal animals, the eardrum pressure is roughly 5 dB higher than the free-field pressure in the frequency range 1-10 kHz. This boost is attributed partly to the effects of the body and partly to the sound-pressure transformation by the outer ear. [ABSTRACT FROM AUTHOR]

A combination of mathematical modeling techniques and computer simulation methods has been used for the interpretation of the behavior of the experimentally observed cochlear potentials. In particular, the models of the mechano-acoustical system and of the electrical potential generating mechanism of the transducer cells have been derived in terms of state variables and of equivalent functional relationships, respectively. These formulations allow economical numerical solution of the complex equations which describe cochlear functions. Using these techniques we have been able to confirm that nonlinearity of the individual haircell output is compatible with the observed apparent linearity of the experimentally observed macroscopic CM (cochlear microphonic) potential and that effective low-pass filtering reduces distortion in the measured potential waveform due to the interaction of the electrical outputs of the haircells along the basilar membrane. This filtering is not influenced to a great extent by the attenuation along the cochlea. Further filtering may also be contributed by the RC networks formed by the various membrane capacitances and resistances. Comparison of the experimental and simulated CM vs SPL functions (frequency as parameter) shows that a simple phase cancellation process is not sufficient, but that an additional mechanism must be postulated to account for the decrease of the CM at very high sound intensities; the IHC (internal haircell) output is assumed to be 20 dB less sensitive than the OHC (outer haircell) output and of opposite sign. A similar comparison for the CM amplitude, CM phase, and SP- amplitude as functions of frequency (SPL as parameter) also provides good agreement. Our results demonstrate that the particular behavior of the basilar membrane and the interference effect between haircell outputs account for the majority of electrical phenomena observed by the classical differential electrode method. [ABSTRACT FROM AUTHOR]

Accurate frequency-response data for the cochlear potentials of the guinea pig were required for the description of the electrical events in the inner ear in terms of a mathematical model. Previously used methods did not ensure constancy of the input stimulus to the ear, and it was, therefore, necessary to monitor the sinusoidal-input amplitude and phase at the eardrum. Simultaneously, the cochlear microphonic potential (CM) amplitude and phase were measured over the frequency range 100-10 000 Hz, with differential electrodes inserted in three turns of the guinea pig's cochlea. The CM-amplitude versus frequency curves showed a 'tuning-curve' shape in general, but the exact shape of these curves was influenced by the location of the electrodes and the sound pressure level (SPL) used. The peak of the CM-amplitude versus frequency plots never appeared at frequencies higher than 2000 Hz owing to the 'low-pass' characteristics of the middle ear. The CM-phase versus frequency plots showed increasing phase lag, but there was relatively slow increase of the measured phase delay in the basal turn. Both these observations and the CM-amplitude measurements indicated that the electrodes picked up the CM from many potential generators that were not excited in phase and that interference between the outputs of the individual hair-cell generators occurred. [ABSTRACT FROM AUTHOR]