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Longitudinal associations between adiposity and change in knee pain : Tasmanian older adult cohort study
No full textObjective: The aim of this study was to describe the longitudinal relationship between adiposity and change in knee pain. Methods: A total of 1099 participants aged 50-79 were randomly selected from the local community in Southern Tasmania, of which 767 were followed up on average 5.1 years later. Knee pain was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at each time point. Consistent knee pain was defined as knee pain at all three time-points. The five pain subscales were grouped into weight-bearing pain and non-weight-bearing pain according to the nature of pain. Body fat and lean mass were assessed using dual energy x-ray absorptiometry (DXA). Results: Baseline body mass index (BMI) and body fat mass were deleteriously associated with consistent knee pain over follow-up. BMI was consistently associated with increases in weight-bearing and non-weight-bearing pain. Fat mass was associated with an increase in non-weight-bearing pain. In mixed-model analyses, WOMAC total pain score was associated with BMI (β = 1.27) and body fat mass (β = 1.17). The association of lean mass was not significant after adjustment for fat mass. Conclusion: BMI is the most consistent correlate of knee pain in older adults. Fat mass is associated with non-weight-bearing knee pain suggesting systemic mechanisms are involved.6 page(s
Objective measures of neural processing of interaural time differences
No full textWe assessed neural sensitivity to interaural time differences (ITDs) conveyed in the temporal fine structure (TFS) of low-frequency sounds and ITDs conveyed in the temporal envelope of amplitude-modulated (AM’ed) high-frequency sounds. Using electroencephalography (EEG), we recorded brain activity to sounds in which the interaural phase difference (IPD) of the TFS (or the modulated temporal envelope) was repeatedly switched between leading in one ear or the other. When the amplitude of the tones is modulated equally in the two ears at 41 Hz, the interaural phase modulation (IPM) evokes an IPM following-response (IPM-FR) in the EEG signal. For low-frequency signals, IPM-FRs were reliably obtained, and largest for an IPM rate of 6.8 Hz and when IPD switches (around 0°) were in the range 45–90°. IPDs conveyed in envelope of high-frequency tones also generated IPM-FRs; response maxima occurred for IPDs switched between 0° and 180° IPD. This is consistent with the interpretation that distinct binaural mechanisms generate the IPM-FR at low and high frequencies, and with the reported physiological responses of medial superior olive (MSO) and lateral superior olive (LSO) neurons in other mammals. Low-frequency binaural neurons in the MSO are considered maximally activated by IPDs in the range 45–90°, consistent with their reception of excitatory inputs from both ears. High-frequency neurons in the LSO receive excitatory and inhibitory input from the two ears receptively—as such maximum activity occurs when the sounds at the two ears are presented out of phase.9 page(s
A Test of the 'one-point method' for estimating maximum carboxylation capacity from field-measured, light-saturated photosynthesis
No full textCorrigendum can be found in 'New Phytologist', Vol. 212, Issue. 3, p. 792. doi: http://dx.doi.org/10.1111/nph.1417215 page(s
Dating the last major eruption of Long Island, Papua New Guinea : the evidence from Dampier's 1700 voyage on the Roebuck
No full textWilliam Dampier, one of England's greatest navigators, named, described, and drew a profile of Long Island, Papua New Guinea in 1700. As this island produced a very large volcanic eruption with a disputed seventeenth- or eighteenth-century date, his observations assist in determining whether the eruption occurred before or after his visit. This contribution uses Dampier's recorded observations to elucidate where the Roebuck was when the Long Island profile was drawn so that an appropriate comparison can be made with a modern profile of the island. This comparison confirms that the most recent major eruption of Long Island occurred before Dampier's observations were made.21 page(s
The Limits of dispersal : fine scale spatial genetic structure in Australian sea lions
No full textDescribing patterns of connectivity throughout a species range is critical to conservation management. In common with other mammals, pinnipeds typically display male-biased dispersal. Earlier studies using mitochondrial DNA showed that the endangered Australian sea lion (Neophoca cinerea) exhibits extreme matrilineal structure throughout its range. If male dispersal were similarly restricted, most breeding colonies may not receive sufficient levels of new genetic variation to buffer against risks associated with inbreeding and environmental change. To address these concerns we used 16 microsatellite loci to obtain a more highly resolving measure of genetic structure among colonies and determine whether dispersal is male-biased. We found that both male and female Australian sea lions are highly philopatric with limited dispersal. Within those constraints, when animals disperse between close colonies (<110 km) there is a tendency for males to move further than females. Our findings are intriguing considering the dispersal potential of Australian sea lions and the unique asynchronous breeding opportunities that might be expected to provide an incentive for male reproductive movements between geographically close colonies.12 page(s
Preliminary results of an array of resonant cavity antennas at 60 GHz
No full textIn this paper, preliminary results of an array of resonant cavity antennas (RCAs) to operate at 60 GHz are presented. Each RCA in the array has a two-layers all-dielectric superstructure with permittivity variation in axial direction. The single RCA element exhibits a peak directivity of 16.6 dBi and its 3dB directivity bandwidth covers the entire unlicensed 60 GHz band from 59 GHz to 67 GHz. The RCA array has a peak directivity of 22.8 dBi with a 3dB directivity bandwidth of 33%. The inter-element spacing between the array elements is optimized to achieve the best performance in terms of peak directivity and radiation bandwidth. The total area of the RCA array is 3.8λ0 × 3.8λ0.2 page(s
Reading and reinterpreting picture books on children’s television : implications for young children’s narrative literacy
No full textBookaboo is a television programme aiming to promote literacy and reading among young children. In each episode, a celebrity reads a book to Bookaboo, a dog who plays the drums in a rock band, in order to help him overcome stage fright. Using the episode featuring the picture book (Cowell and Layton in That Rabbit Belongs to Emily Brown, 2006) as a case study, this article explores how this type of adaptation of picture books transforms the original narrative, with implications for children’s developing narrative literacy. Taking a multimodal social semiotic perspective, this study investigates the changes in meaning which result from the employment of semiotic resources such as animation, sound, and camera movement in the representation of the book on the television show. We argue that the deployment of such resources can subtly reshape the meanings expressed through the modes of language and images in the original picture book, potentially affecting the child viewer’s engagement with the narrative. Examining the use of these resources in the picture book’s televisual representation is thus an important first step towards developing frameworks for evaluating the ability of television programmes that incorporate picture book reading to support children’s literacy.19 page(s
Sensitivity to interaural time differences conveyed in the stimulus envelope : estimating inputs of binaural neurons through the temporal analysis of spike trains
No full textSound-source localization in the horizontal plane relies on detecting small differences in the timing and level of the sound at the two ears, including differences in the timing of the modulated envelopes of high-frequency sounds (envelope interaural time differences (ITDs)). We investigated responses of single neurons in the inferior colliculus (IC) to a wide range of envelope ITDs and stimulus envelope shapes. By a novel means of visualizing neural activity relative to different portions of the periodic stimulus envelope at each ear, we demonstrate the role of neuron-specific excitatory and inhibitory inputs in creating ITD sensitivity (or the lack of it) depending on the specific shape of the stimulus envelope. The underlying binaural brain circuitry and synaptic parameters were modeled individually for each neuron to account for neuron-specific activity patterns. The model explains the effects of envelope shapes on sensitivity to envelope ITDs observed in both normal-hearing listeners and in neural data, and has consequences for understanding how ITD information in stimulus envelopes might be maximized in users of bilateral cochlear implants—for whom ITDs conveyed in the stimulus envelope are the only ITD cues available.18 page(s
West Papua, Indonesia and the Melanesian Spearhead Group : competing logics in regional and international politics
No full textThe idea of a shared Melanesian identity has been consolidated over the last three decades or so through the most important subregional organisation in the South-West Pacific—the Melanesian Spearhead Group (MSG). The solidarity of this group has been strained over various issues from time to time, but none is as fraught as the Indonesian occupation of what is commonly known as West Papua, whose indigenous Papuan people are ethnically Melanesian. In addition to recounting the Indonesian takeover of West Papua in the context of the dynamics of decolonisation, the Cold War and early regional development, the article examines the emergence of Melanesian identity and the MSG, before considering more recent developments. These focus on a recent bid by West Papuans for MSG membership, key aspects of Indonesia's role in the Melanesian subregion, and the extent to which these developments highlight competing logics in regional and international politics.19 page(s
Testing psychological forward induction and the updating of beliefs in the lost wallet game
No full textThis paper studies psychological forward induction and the updating of beliefs in the lost wallet game (Dufwenberg & Gneezy, 2000), which is required to derive a prediction for guilt averse agents. Our experiment tests whether the second movers psychologically induct forward and update their beliefs after observing their paired first mover's decision by eliciting beliefs with different second mover knowledge of first mover decision, depending on treatment. We find that second movers do update their beliefs conditional on receiving information on the first mover's action, supporting psychological forward induction.10 page(s