A. Richard Palmer

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The acoustically induced motion of the eardrum of the frog was measured by an incoherent optical technique. When free-field sound stimulation was used, the eardrum vibration had a band-pass characteristic with maximum amplitude at 1-2.5 kHz. However, when the sound was presented in a closed-field acoustic coupler the response was low-pass (cut-off frequency(More)
We present several models concerning the short term consequences of spreading offspring in varying environments. Our goal is to determine what patterns of spatial and temporal variation yield an advantage to increasing scale of dispersal. Of necessity, the models are somewhat artificial but we feel they are a reasonable approximation of and hence(More)
Field observations and experiments revealed that predatory intertidal gastropods of the genus Thais (or Nucella) were able both to recognize the expected food value of encountered prey (expected energy or growth potential gained per unit handling time) and to monitor their average yield over time (average energy or growth potential gained per unit foraging(More)
Data on the distribution of root biomass are critical to understanding the ecophysiology of vegetation communities. This is particularly true when models are applied to describe ecohydrology and vegetation function. However, there is a paucity of such information across continental Australia. We quantified vertical and horizontal root biomass distribution(More)
The responses to single (/a/ and /i/) and double vowel (/a,i/) stimuli of normal guinea pig cochlear nerve fibres are compared with those from animals with a cochlear hearing loss. When the threshold losses are sufficient to exclude the higher harmonics of the /i/, the temporal representation of the second and higher formants is lost. Smaller threshold(More)
The frog ear can be modelled as two coupled eardrums with an additional sound pathway through the mouth cavity. In a previous version of this model, with realistic parameters, we were able to account very well for empirical measurements of the eardrum vibration under free- and closed-field acoustic conditions. This earlier model does not, however,(More)
Solid state 33S NMR spectra of a variety of inorganic sulfides have been obtained at magnetic field strengths of 4.7 and 17.6T. Spectra acquired with magic angle spinning show considerable improvements in sensitivity and resolution when compared with static spectra. Multiple factors are considered when analyzing the spectral line widths, including; magnetic(More)
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