A modulator for discrete trains of pulses

A circuit is described which provides a means of modulating trains of pulses of duration from 1 msec up to 1.5 sec. This device was especially designed for use with Grass Instruments Co. stimulators so that only one stimulator is needed for generating trains of pulses. In addition, there is a neon multivibrator which controls the repetition rate and also can delay the turn-on of the modulator from the beginning pulse of the multivibrator. The circuits and power supply are contained on the chassis and the controls are mounted on the front panel of the stimulator.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32036/1/0000079.pd

On Bitangential Interpolation in the Time Varying Setting for Hilbert-Schmidt Operators: The Continuous Case

The Hilbert space of lower triangular Hilbert–Schmidt operators on the real line is a natural analogue of the Hardy space of a half-plane, where the complex numbers are now replaced by matrix-valued functions. One can associate with a bounded operator its “values” at a matrix-valued function [see Ballet al.,Oper. Theory Adv. Appl.56(1992), 52–89], and this allows [see Ballet al.,Integral Equations Operator Theory20(1994), 1–43] to define and solve the analogue of the two-sided Nudelman interpolation problem for bounded operators (which form an analogue ofH∞(C+)). In this paper we consider the two-sided interpolation problem with a Hilbert–schmidt norm constraint (rather than the more common operator-norm constraint) on the interpolant

On Bitangential Interpolation in the Time Varying Setting for Hilbert-Schmidt Operators: The Continuous Case

The Hilbert space of lower triangular Hilbert–Schmidt operators on the real line is a natural analogue of the Hardy space of a half-plane, where the complex numbers are now replaced by matrix-valued functions. One can associate with a bounded operator its “values” at a matrix-valued function [see Ballet al.,Oper. Theory Adv. Appl.56(1992), 52–89], and this allows [see Ballet al.,Integral Equations Operator Theory20(1994), 1–43] to define and solve the analogue of the two-sided Nudelman interpolation problem for bounded operators (which form an analogue ofH∞(C+)). In this paper we consider the two-sided interpolation problem with a Hilbert–schmidt norm constraint (rather than the more common operator-norm constraint) on the interpolant

Financial Market Intermediaries and Information Asymmetry in Equity Markets

This dissertation examines the relationship between financial market intermediaries and information asymmetry. Chapters 5, 6, and 7 re-examines issues raised in the literature, but extends this research by using unique datasets not previously available to researchers. Overall, the results show that (i) market intermediaries help reduce information asymmetry in upstairs markets by filtering out information-motivated trades, (ii) market intermediaries produce information which is valuable to clients who are able to trade ahead of the market, and iii) market intermediaries are heterogeneously informed, and are therefore affected differently by a change in market structure

A motivational analyses of the reticular activating system

In 51 rats electrode pairs were chronically implanted with spacing 1 mm. apart from rat to rat to make a grid of the tegmentum. In each case three tests were made: a self-stimulation test for positive reinforcement; an escape test for negative reinforcement; and an EEG test for cortical arousal. The main results were these: all points yielding escape at very low thresholds were clustered in the dorso-medial tegmentum just below the tectum and just lateral to the central grey; all points yielding self-stimulation at high rates were clustered ventrally, usually below and lateral to the medial lemniscus; and points yielding arousal at very low thresholds were clustered in the lateral tegmentum, half-way up from the ventral surface.As for interactions between the three effects, all points yielding escape at low thresholds also yield arousal at low thresholds; al points yielding self-stimulation at high rates yielded arousal at moderately high thresholds; and some points yielded both moderate escape and moderate self-stimulation. Finally, there definitely were points which yielded arousal at low thresholds and which yielded no other motivational effects.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32417/1/0000496.pd

The Bridgwater Infant Welfare Centre, 1922-1939: from an authoritarian concern with 'welfare mothers' to a more inclusive community health project?

The infant welfare movement in Britain has received considerable scholarly attention but continues to generate controversy and debate. Many of the services began with nineteenth-century voluntary initiative but were later developed by local authorities. Critics have drawn attention to the limitations of such provision; arguing that it was predicated on unattractive assumptions about class and gender roles. Under this interpretation working-class mothers were viewed with suspicion and targeted for advice aimed at inculcating middle-class standards of childcare and housekeeping. This paper accepts that there was an authoritarian character to much of the early welfare work but suggests that over time this gave way to more inclusive approaches that sought to provide clients with the services that met their real rather than assumed needs. This paper reviews the recent historiography, develops an overview of national trends, and then takes a detailed look at the Bridgwater Infant Welfare Centre. The case study benefi ts from unusually comprehensive records and, by drawing on evidence from a small Somerset town, adds to our understanding of infant welfare work that has previously been developed from research on major urban centres.Wellcome Trust Fellowshi

Faster decline of pitch memory over time in congenital amusia

Congenital amusia (amusia, hereafter) is a developmental disorder that impacts negatively on the perception of music. Psychophysical testing suggests that individuals with amusia have above average thresholds for detection of pitch change and pitch direction discrimination; however, a low-level auditory perceptual problem cannot completely explain the disorder, since discrimination of melodies is also impaired when the constituent intervals are suprathreshold for perception. The aim of the present study was to test pitch memory as a function of (a) time and (b) tonal interference, in order to determine whether pitch traces are inherently weaker in amusic individuals. Memory for the pitch of single tones was compared using two versions of a paradigm developed by Deutsch (1970a). In both tasks, participants compared the pitch of a standard (S) versus a comparison (C) tone. In the time task, the S and C tones were presented, separated in time by 0, 1, 5, 10, and 15 s (blocked presentation). In the interference task, the S and C tones were presented with a fixed time interval (5 s) but with a variable number of irrelevant tones in between: 0, 2, 4, 6, and 8 tones (blocked presentation). In the time task, control performance remained high for all time in tervals, but amusics showed a performance decrement over time. In the interference task, controls and amusics showed a similar performance decrement with increasing number of irrelevant tones. Overall, the results suggest that the pitch representations of amusic individuals are less stable and more prone to decay than those of matched non-amusic individuals