bluuebunny/crossref_metadata_2025_split huggingface dataset:
Patterns of home and community care service delivery to culturally and linguistically diverse residents of rural Victoria
Authors: Ward Bernadette M. , Anderson Karen S. , Sheldon Maria S. 
Published: November 2005

AbstractObjective:  To describe and compare patterns of Home and Community Care (HACC) utilisation among culturally and linguistically diverse (CALD) people and Australian‐born residents of rural Victoria. Design:  The HACC Minimum Data Set provides information regarding levels of service provision and coverage in Victoria. Data from January to June 2002 were analysed to provide a profile of client characteristics and service usage in rural Victoria. Patterns of service utilisation were compared with the profile of the CALD population in the 2001 Census. Results:  The proportion of CALD residents who are HACC clients is consistent with demographic profiles. However, their extent of service usage is not consistent with patterns of use by Australian‐born residents. HACC clients born in non‐English‐speaking countries, receive 35% less hours of HACC service than their Australian‐born counterparts. HACC clients born overseas in English‐speaking countries receive nine per cent less hours of HACC service than the Australian‐born group (F = 8.9, P = 0.00). Both groups of overseas‐born clients use a smaller range of HACC services (F = 1.9, P = 0.16).Conclusion:  Planners and service providers need to monitor levels of HACC service delivery among population groups to ensure that CALD population groups receive equitable levels of HACC services. The HACC Minimum Data Set is one source of data that can assist in this process.
Do health and medical workforce shortages explain the lower rate of rural consumers' complaints to Victoria's Health Services Commissioner?
Authors: Jones Judith A. , Humphreys John S. , Wilson Beth 
Published: November 2005

AbstractObjective:  To identify which explanations account for lower rural rates of complaint about health services – (i) fear of consequences where there is little choice of alternative provider; (ii) a higher complaint threshold for rural consumers; (iii) lack of access to complaint mechanisms; or (iv) reduced access to services about which to complain. Design:  Ecological study incorporating consumer complaint, population and workforce distribution data sources. Setting:  All health care providers practising in Victoria. Participants:  De‐identified records of all closed consumer complaints made to the Health Services Commissioner, Victoria, between March 1988 and April 2001 by Victorian residents (13 856 records). Main outcome measures:  Differences in the percentage of under‐representation in complaint rates in total and for each of four categories of health services providers for different size communities. Results:  No consistent relationship was observed between community size and either degree of under‐representation of complaints against any category of provider, or the proportion of serious or substantial complaints. Rural under‐representation was highest (41%) for dentists, the provider category with the lowest proportion working in rural areas (17%), and lowest (18%) for hospitals, with the highest representation in rural areas (28% of beds). More rural complaints were about access issues (10.7% rural and 8.4% metropolitan). Conclusions:  Reduced opportunity to use health services due to rural health and medical workforce shortages was the best‐supported explanation for the lower rural complaint rate. Workforce shortages impact on the quality of rural health services and on residents’ opportunities to improve their health status.
Modelling of fatigue‐corrosion in Ti6246 alloy at 500°c
Authors: SARRAZIN‐BAUDOUX C. 
Published: November 2005

ABSTRACTThis paper deals with a study of the influence of the atmospheric environment on the resistance against fatigue crack propagation of a Ti6246 titanium alloy at 500°C. Tests were performed in the near‐threshold and mid‐rate ranges under controlled gaseous environments, including vacuum and argon, with controlled partial pressures of water vapour and oxygen. A predominant detrimental influence of water vapour is demonstrated even under very low partial pressure, while oxygen gas is shown to moderate the influence of water vapour. A crack‐propagation model relating the growth rate to the effective stress intensity factor range is proposed to account for this competitive influence of water vapour and oxygen with respect to the test frequency.
Strain‐based multiaxial fatigue damage modelling
Authors: LIU Y. , MAHADEVAN S. 
Published: November 2005

ABSTRACTA new multiaxial fatigue damage model named characteristic plane approach is proposed in this paper, in which the strain components are used to correlate with the fatigue damage. The characteristic plane is defined as a material plane on which the complex three‐dimensional (3D) fatigue problem can be approximated using the plane strain components. Compared with most available critical plane‐based models for multiaxial fatigue problem, the physical basis of the characteristic plane does not rely on the observations of the fatigue crack in the proposed model. The cracking information is not required for multiaxial fatigue analysis, and the proposed model can automatically adapt for different failure modes, such as shear or tensile‐dominated failure. Mean stress effect is also included in the proposed model by a correction factor. The life predictions of the proposed fatigue damage model under constant amplitude loading are compared with a wide range of metal fatigue results in the literature.
Slow endogenous activity transients and developmental expression of K+–Cl− cotransporter 2 in the immature human cortex
Authors: Vanhatalo Sampsa , Palva J. Matias , Andersson Sture , Rivera Claudio , Voipio Juha , Kaila Kai 
Published: November 2005

AbstractSpontaneous transients of correlated activity are a characteristic feature of immature brain structures, where they are thought to be crucial for the establishment of precise neuronal connectivity. Studies on experimental animals have shown that this kind of early activity in cortical structures is composed of long‐lasting, intermittent network events, which undergo a developmental decline that is closely paralleled by the maturation of GABAergic inhibition. In order to examine whether similar events occur in the immature human cortex, we performed direct current‐coupled electroencephalography (EEG) recordings from sleeping preterm babies. We show now that much of the preterm EEG activity is confined to spontaneous, slow activity transients. These transients are characterized by a large voltage deflection that nests prominent oscillatory activity in several frequency bands covering the whole frequency spectrum of the preterm EEG (<0.1–30 Hz). The slow voltage deflections had an amplitude of up to 800 µV. Most of these ‘giant’ events originated in the temporo‐occipital areas, with a maximum rate of about 8/min, and their occurrence as well as amplitude showed a decline by the time of normal birth. In age‐matched fetal brain tissue, this decrease in the spontaneous activity transients was associated with a developmental up‐regulation of the neuronal chloride extruder K+–Cl− cotransporter 2, a crucial molecule for the generation of inhibitory GABAergic Cl– currents. Our work indicates that slow endogenous activity transients in the immature human neocortex are mostly confined to the prenatal stage and appear to be terminated in parallel with the maturation of functional GABAergic inhibition.
Statistical properties of information processing in neuronal networks
Authors: Bonifazi Paolo , Ruaro Maria Elisabetta , Torre Vincent 
Published: November 2005

AbstractInformation processing and coding were analysed in dissociated hippocampal cultures, grown on multielectrode arrays. Multisite stimulation was used to activate different neurons and pathways of the network. The neural activity was binned into firing rates and the variability of the firing of individual neurons and of the whole population was analysed. In individual neurons, the timing of the first action potential (AP) was rather precise from trial to trial, whereas the timing of later APs was much more variable. Pooling APs in an ensemble of neurons reduced the variability of the response and allowed stimuli varying in intensity to be distinguished reliably in a single trial. A similar decrease of variability was observed pooling the first evoked APs in an ensemble of neurons. The size of the neuronal pool (∼ 50–100 neurons) and the time bin (∼ 20 ms) necessary to provide reproducible responses are remarkably similar to those obtained in in vivo preparations and in small nervous systems. Blockage of excitatory synaptic pathways mediated by NMDA receptors improved the mutual information between the evoked response and stimulus properties. When inhibitory GABAergic pathways were blocked by bicuculline the opposite effect was obtained. These results show how ensemble averages and an appropriate balance between inhibition and excitation allow neuronal networks to process information in a fast and reliable way.
Neuromagnetic correlates of visual motion coherence
Authors: Aspell J. E. , Tanskanen T. , Hurlbert A. C. 
Published: November 2005

AbstractIn order to characterize cortical responses to coherent motion we use magnetoencephalography (MEG) to measure human brain activity that is modulated by the degree of global coherence in a visual motion stimulus. Five subjects passively viewed two‐phase motion sequences of sparse random dot fields. In the first (incoherent) phase the dots moved in random directions; in the second (coherent) phase a variable percentage of dots moved uniformly in one direction while the others moved randomly. We show that: (i) visual‐motion‐evoked magnetic fields, measured with a whole‐scalp neuromagnetometer, reveal two transient events, within which we identify two significant peaks – the ‘ON‐M220’ peak approximately 220 ms after the onset of incoherent motion and the ‘TR‐M230’ peak, approximately 230 ms after the transition from incoherent to coherent motion; (ii) in lateral occipital channels, the TR‐M230 peak amplitude varies with the percentage of motion coherence; (iii) two main sources are active in response to the transition from incoherent to coherent motion, the human medial temporal area complex/V3 accessory area (hMT+/V3A) and the superior temporal sulcus (STS), and (iv) these distinct areas show a similar, significant dependence of response strength and latency on motion coherence.
Fine tuning of olfactory orientation behaviour by the interaction of oscillatory and single neuronal activity
Authors: Nikitin Evgeny S. , Zakharov Igor S. , Samarova Elena I. , Kemenes György , Balaban Pavel M. 
Published: November 2005

AbstractWe used a simple sensory and motor system to investigate the neuronal mechanisms of olfactory orientation behaviour. The main olfactory organs of terrestrial molluscs, the experimental animals used in this work, are located on the tips of their tentacles, which display complex movements when they explore a new environment. By reconstructing the trajectory of the tentacle tip (‘nose’) movements in three dimensions in freely moving snails, we showed that the protracted tentacles performed continuous scanning, both spontaneously and in response to odours. Odour applications elicited a brief startle‐like quiver of the tentacle in a concentration‐independent manner as well as a concentration‐dependent contraction. Previous work showed that activation of an identified cerebral motoneuron, MtC3, produces tentacle contraction. Here we showed that in semi‐intact preparations, MtC3 responded to odours in a concentration‐dependent manner, similar to the tentacle contraction response to the same odours in intact animals. This observation suggests that MtC3 is involved in the central control of the scanning area by regulating the tentacle length. Using voltage‐sensitive dyes and imaging, we demonstrated that during the hyperpolarizing phases of oscillations in the procerebral lobe, the main olfactory centre of the CNS of terrestrial molluscs, MtC3 spike frequency significantly decreased. We also showed that direct activation of the procerebral lobe resulted in the phasic inhibition of MtC3. This is therefore an example of an olfactory system in which the interaction of oscillatory and single neuronal activity plays an important role in the fine tuning of orientation behaviour to suit the particular odour environment.
A shift of visual spatial attention is selectively associated with human EEG alpha activity
Authors: Sauseng P. , Klimesch W. , Stadler W. , Schabus M. , Doppelmayr M. , Hanslmayr S. , Gruber W. R. , Birbaumer N. 
Published: November 2005

AbstractEvent‐related potentials and ongoing oscillatory electroencephalogram (EEG) activity were measured while subjects performed a cued visual spatial attention task. They were instructed to shift their attention to either the left or right visual hemifield according to a cue, which could be valid or invalid. Thereafter, a peripheral target had to be evaluated. At posterior parietal brain areas early components of the event‐related potential (P1 and N1) were higher when the cue had been valid compared with invalid. An anticipatory attention effect was found in EEG alpha magnitude at parieto‐occipital electrode sites. Starting 200 ms before target onset alpha amplitudes were significantly stronger suppressed at sites contralateral to the attended visual hemifield than ipsilateral to it. In addition, phase coupling between prefrontal and posterior parietal electrode sites was calculated. It was found that prefrontal cortex shows stronger phase coupling with posterior sites that are contralateral to the attended hemifield than ipsilateral sites. The results suggest that a shift of attention selectively modulates excitability of the contralateral posterior parietal cortex and that this posterior modulation of alpha activity is controlled by prefrontal regions.
Long‐term changes in blood–brain barrier permeability and white matter following prolonged systemic inflammation in early development in the rat
Authors: Stolp H. B. , Dziegielewska K. M. , Ek C. J. , Potter A. M. , Saunders N. R. 
Published: November 2005

AbstractEpidemiological evidence in human fetuses links inflammation during development with white matter damage. Breakdown of the blood–brain barrier has been proposed as a possible mechanism. This was investigated in the present study by inducing a prolonged inflammatory response in newborn rats, with intraperitoneal injections of lipopolysaccharide (LPS; 0.2 mg/kg) given at postnatal (P) day 0, P2, P4, P6 and P8. An acute phase response was present over the whole period of injections. Changes in blood–brain barrier permeability were determined for small (sucrose and inulin) and large (protein) molecules. During and immediately after the inflammatory response, plasma proteins were detected in the brain only within white matter tracts, indicating an increased permeability of the blood–brain barrier to protein during this period. The alteration in permeability to protein was transient. In contrast, the permeability of the blood–brain barrier to 14C‐sucrose and 14C‐inulin was significantly higher in adult animals that had received serial LPS injections during development. Adult animals receiving a single 1 mg/kg LPS injection at P0 showed no alteration in blood–brain barrier permeability to either small or larger molecules. A significant decrease in the volume of CNPase immunoreactive presumptive white matter tracts occurred in the external capsule and corpus callosum at P9. These results demonstrate that a prolonged systemic inflammatory response in the early postnatal period in rats causes size selective increases in blood–brain barrier permeability at different stages of brain development and results in changes in white matter volume.
Scene perception: inferior temporal cortex neurons encode the positions of different objects in the scene
Authors: Aggelopoulos Nikolaos C. , Rolls Edmund T. 
Published: November 2005

AbstractInferior temporal cortex (IT) neurons have reduced receptive field sizes in complex natural scenes. This facilitates the read‐out of information about individual objects from IT, but raises the question of whether more than the single object present at the fovea is represented by the firing of IT neurons, as would be important for whole scene perception in which several objects may be located without eye movements. Recordings from IT neurons with five simultaneously presented objects, each subtending 7°, with one object at the fovea and the other four centred 10° eccentrically in the parafovea, showed that although 38 IT neurons had their best response to an effective stimulus at the fovea, eight IT neurons had their best response to an object when it was located in one or more of the parafoveal positions. Moreover, of 54 neurons tested for asymmetric parafoveal receptive fields, 35 (65%) had significantly different responses for different parafoveal positions. The asymmetry was partly related to competition within the receptive fields, as only 21% of the neurons had significant asymmetries when tested with just one object present located at the same parafoveal positions. The findings thus show that some evidence is conveyed by a population of IT neurons about the relative positions of several simultaneously presented objects in a scene extending well into the parafovea during a single fixation, and this is likely to be important in whole scene perception with multiple objects, including specifying the relative positions of different objects in a scene.
Aberrant trajectory of thalamocortical axons associated with abnormal localization of neurocan immunoreactivity in the cerebral neocortex of reeler mutant mice
Authors: Li Hong‐Peng , Oohira Atsuhiko , Ogawa Masaharu , Kawamura Koki , Kawano Hitoshi 
Published: November 2005

AbstractWe examined the molecular mechanisms underlying the formation of the thalamocortical pathway in the cerebral neocortex of normal and reeler mutant mice. During normal development of the mouse neocortex, thalamic axons immunoreactive for the neural cell adhesion molecule L1 rarely invaded the cortical plate and ran centered in the subplate which is immunoreactive for neurocan, a brain‐specific chondroitin sulfate proteoglycan. On the other hand, in homozygous reeler mutant mice, thalamic axons took an aberrant course to run obliquely through the cortical plate. Injection of bromodeoxyuridine at embryonic day 11 specifically labeled subplate neurons in normal mice, whilst in the reeler neocortex it labeled cells scattered in the cortical plate as well as in the superficial layer (superplate). Neurocan immunoreactivity was associated with the bromodeoxyuridine‐positive cells in the superplate, as well as being present in oblique bands within the cortical plate, along which L1‐bearing thalamic axons preferentially ran. The present results support our previous hypothesis proposed for normal rats that a heterophilic molecular interaction between L1 and neurocan is involved in determining the thalamocortical pathway within the neocortical anlage [T. Fukuda et al. (1997)Journal of Comparative Neurology, 382, 141–152].
Dysfunction of the cortico‐basal ganglia‐cortical loop in a rat model of early parkinsonism is reversed by metabotropic glutamate receptor 5 antagonism
Authors: Oueslati Abid , Breysse Nathalie , Amalric Marianne , Kerkerian‐Le Goff Lydia , Salin Pascal 
Published: November 2005

AbstractThis study examined the cellular correlates of the akinetic deficits produced in Wistar rats by discrete bilateral 6‐hydroxydopamine (6‐OHDA) striatal infusions in the dorsolateral striatum, mimicking the preferential denervation of the motor striatal territory in early symptomatic stage of Parkinson's disease (PD). Intraneuronal gene expression of cytochrome oxidase subunit I (COI), a metabolic index of neuronal activity, was increased in the subthalamic nucleus, substantia nigra pars reticulata and decreased in frontal cortical areas, but paradoxically unchanged in the striatum, globus pallidus, entopeduncular nucleus and ventrolateral thalamic nucleus. Neither preproenkephalin A nor preprotachykinin mRNA expression, markers of striatal projection neurons, were modified in the denervated striatal area despite 90% loss of dopamine (DA) terminals. Preproenkephalin A mRNA expression was however, decreased in the nondepleted striatal region, suggesting compensatory increase of dopamine tone from those spared areas. A chronic treatment with the metabotropic glutamate receptor 5 (mGluR5) antagonist 2‐methyl‐6‐(phenylethylnyl)‐pyridine (MPEP), which alleviated the akinetic disorders produced by the lesion, reversed the lesion‐induced variations of COI gene expression, moderately increased this marker in the structures unaffected by the lesion and did not modify the striatal neuropeptides gene expression. These data suggest that the expression of akinetic deficits in early parkinsonism is associated with focused metabolic changes in the cortico‐basal ganglia‐cortical loop downstream of the striatum and pallidal complex.
Cognitive flexibility and decision‐making in a model of conditional visuomotor associations
Authors: Loh Marco , Deco Gustavo 
Published: November 2005

AbstractArbitrary visuomotor associations map a stimulus onto a particular response upon reinforcing rewards. Changes in the associations between stimuli and responses require the neural networks to discard the already learned mappings and build new ones. This is a key aspect of cognitive flexibility. In addition, learning within this experimental paradigm requires a trial‐and‐error exploration strategy of the available stimulus–response associations. A system performing this task must be able to both build up mappings for stimulus–response associations and at the same time perform non‐deterministically to explore the behavioural space until it reaches certainty. We hypothesize an integrate‐and‐fire network model that accounts for the neurophysiological data of a conditional visuomotor association task and is able to show non‐deterministic behaviour. We aim at identifying multistable attractor regimes in the network dynamics, which intrinsically enable the system to make errors and thereby to perform trial‐and‐error exploration. Our model combines cognitive flexibility with multistable attractors in neurodynamical systems, believed to be the basis of decision‐making. If multistable attractors support the exploration of the behavioural space, then our model predicts that the brain should respond stochastically with correct or incorrect activity to visuomotor associations until it has reached certainty. This should be visible not only in the corresponding activity in the premotor area, but also in activity corresponding to other associations or even other stimuli in the prefrontal cortex.
Monitoring cerebral oxygenation in a pediatric patient undergoing surgery for vascular ring
Authors: JOSHI REENA K , MOTTA PABLO , HORIBE MAYUMI , MOSSAD EMAD 
Published: November 2005

SummaryRegional cerebral oxygenation can be monitored using near‐infrared spectroscopy (NIRS). Inadequacy of collateral cerebral circulation and regional cerebral ischemia during cardiac and vascular surgery may be detected by the use of NIRS monitoring. We report a 2‐year‐old child who underwent surgical repair of vascular ring and subclavian reimplantation, where use of NIRS helped in early detection and timely intervention to prevent prolonged cerebral ischemia.