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1.
Whose values matter when considering which environment is healthier for a child whose guardianship is contested? The biological mother from a remote Australian Aboriginal community, who voluntarily relinquished her but has now requested her return? The foster mother who has cared for her in a metropolitan centre in another State of Australia, thousands of kilometres away? The welfare professionals who also live in that city? Or the child herself, who left her birth home and community five years earlier at the age of two? Drawing on a case study of a seven-year old Aboriginal girl, the authors argue that non-Indigenous values trumped Indigenous values without the realisation of key players who were empowered to make such determinations. The article uses Manuel DeLanda's neo-assemblage theory to consider the range of processes that exert themselves to shape place-values and social identity in colonised nations. It will also draw on Erik Erikson's and Lev Vygotsky's theories of psychosocial development to consider competing sets of values that raised feelings of dissonance within the child. Beliefs about what makes a place health-giving are revealed to be complex in colonised nations. Despite policy and legislative changes to better support Aboriginal people and their right to difference, non-Indigenous professionals can continue to be driven by an unrecognised systemic racism. While place-values are not, of course, the only (or perhaps even the most significant) consideration in guardianship determinations, this article will argue they can play a significant and covert role.  相似文献   
2.
Morphine (8–100 mg/kg IP) induces place preference conditioning in mice. The effect of two different periods of isolation (15 and 30 days) was examined. Mice isolated for 15 days but not 30 days exhibited place preference conditioning to morphine (8 mg/kg). After 30 days of isolation morphine could not induce place preference conditioning with the following doses (8, 16, 64, 100 mg/kg). Social regrouping of male mice previously isolated for 30 days with naive female mice for 15 or 30 days resulted in a reappearance of the conditioned place preference to morphine (16 mg/kg). The specificity of this associative deficit was examined by testing learning in isolated compared to non-isolated mice in two distinct settings: escape learning in the Morris water maze and passive avoidance acquisition and retention. On the Morris water maze isolated mice did not differ from non-isolated mice regarding place learning, the probe trial or extinction. Isolated mice were unimpaired in passive avoidance acquisition and retention. It was concluded that the deficits in place preference conditioning were not the result of a global learning impairment in isolated mice. Received: 10 April 1996 /Final version: 20 September 1996  相似文献   
3.
Anxiolytic benzodiazepines have been shown to impair place learning in the Morris water maze. However, a clear-cut demonstration of a direct and specific effect on mnemonic processes has not yet been offered. In the present study, the effects of diazepam on place navigation in the Morris water maze were studied in rats. Three conditions were examined: learning, reversal learning and learning after familiarisation of animals with the maze. In view of the anxiolytic and sedative properties of diazepam, appropriate doses of the drug, i.e. those that produced an anxiolytic effect but no major motor impairment, were initially selected in the water-lick conflict and rotarod tests, respectively. Doses of 2.5 and 5 mg/kg PO increased punished drinking in the water-lick conflict test without significantly decreasing rotarod performance. These doses were then used to assess the effects of diazepam on spatial behaviour. Diazepam, at both doses, impaired place learning in behaviourally naive rats. Such an effect appeared to be transient: diazepam-treated rats eventually reached control performance. Moreover, analysis of the probe trial at the end of training revealed adoption of a spatial strategy to locate the submerged platform. Neither reversal learning nor learning after familiarisation was affected. These results do not replicate previous findings in the Morris water maze and provide some evidence that the diazepam-induced place learning deficit may be primarily anxiolytic in nature.  相似文献   
4.
Chronic exposure to mild unpredictable stress has previously been found to depress the consumption of a palatable (1%) sucrose solution, and to attenuate food-induced place preference conditioning. In this study the effects of pramipexole (SND-919), a dopamine D2 agonist, were studied during 7–9 weeks of chronic treatment. Pramipexole (1.0 mg/kg per day) reversed the suppression of sucrose intake in stressed animals, increasing sucrose intakes above the levels seen in untreated nonstressed controls. Pramipexole also increased sucrose intake in nonstressed animals; these effects were accompanied by increases in water intake and tended to correlate with weight loss. Drug-treated stressed animals also lost weight, but in this case water intake was unaffected. A second group of animals received a higher dose of pramipexole (2.0 mg/kg per day). The effects of the two doses were very similar. After three weeks of treatment, these animals were switched to a lower dose of pramipexole (0.1 mg/kg per day). Increases in sucrose intake were maintained over three weeks of treatment at the lower dose, with significant recovery of body weight. Two further groups received the same doses of pramipexole (1.0 mg/kg for 6 weeks or 2.0 mg/kg for 3 weeks followed by 0.1 mg/kg thereafter), but received intermittent (twice-weekly) drug treatment. Intermittent pramipexole treatments also tended to increase sucrose intakes, but the results were less consistent from week to week. Following 6–8 weeks of pramipexole treatment, food-induced place preference conditioning was studied in all animals. Untreated stressed animals showed no evidence of place conditioning. Normal conditioning was seen in both groups of stressed animals treated daily with pramipexole (at 1.0 and 0.1 mg/kg) and in the group treated twice weekly at the higher dose (1.0 mg/kg); intermittent treatment at the lower dose (0.1 mg/kg) was ineffective. The results indicate that pramipexole exerts rapid anti-anhedonic effects in the chronic mild stress model. This conclusion is complicated, but not undermined, by drug-induced weight loss and by the presence of significant drug effects in nonstressed control animals.  相似文献   
5.
Although the reconfiguring of health care within the hospital sector has gained considerable attention by social scientists, the tertiary education sector's response to new health philosophies and practices has proceeded largely unexamined. This paper considers the new School of Population Health at the University of Auckland, accounts for its origins and considers the synergies between its design and workplace organisation. The results of a thematic analysis of narratives offered by 24 employees collected in 2004 are then presented. Findings suggest that the amassing of academics from a range of health-related backgrounds is advancing interdisciplinary dialogue even if the nature and purpose of population health remains unclear to some. A key concern of respondents was the openness of the workplace which encourages a collaborative atmosphere but also generates distraction. The degree to which conduct within the new building is perceived as regulated was also of concern. Place clearly matters in the story of the new School: the form of the building (featuring an architecture of openness) complements its function (generating new collaborations and creative thinking about health). However, the question of how ‘salutogenic’ a setting it is remains contested.  相似文献   
6.
A current topic in neurobiology is the study of the role of various brain structures in processing of spatial information. The present study was aimed at elucidating the role of the rat posterior parietal cortex in performing a place avoidance task. Two variants of the task were used: an arena frame task, in which animals were trained to avoid a sector defined by local cues bound to the surface of a rotating arena, and the room frame task, in which the shock sector was defined with respect to distal room landmarks. The results showed that both control and lesioned rats were able to efficiently solve both tasks, while locomotion was not altered. These results suggest that the posterior parietal cortex is not crucial for the processing of either proximal or distal cues in place avoidance.  相似文献   
7.
The turnover rates of adrenaline in the medial preoptic area and mediobasal hypothalamus, areas which, respectively, include the cell bodies and terminals of luteinizing hormone-releasing hormone neurons, have been measured in female rats on pro-oestrus, the day of the preovulatory surge of luteinizing hormone, and on dioestrus, the preceding day. A rise in the rate of turnover was found in the medial preoptic area coinciding with the surge of luteinizing hormone in the late afternoon of pro-oestrus; the rate of turnover at this time was higher than at the same time on dioestrus. No changes in turnover rate were found in the mediobasal hypothalamus within either of these days.The results indicate that the adrenaline-containing projections to the preoptic area may be actively involved in the production of the spontaneous preovulatory surge of luteinizing hormone in rats.  相似文献   
8.
Ambulatory blood pressure was studied as a function of posture, place, and mood in 131 subjects classified according to race, gender, and hypertensive status. The effect of posture was significant and explained a substantial proportion of within-subject variability. After controlling for posture, significant place and mood effects were observed when subjects were sitting but not when they were standing. Home vs. work differences in both systolic and diastolic blood pressure were significantly greater in Whites than in Blacks. Similar differences in systolic blood pressure were greater in mild hypertensive than in normotensive subjects. The results of this study underscore the need to control for effects of posture when interpreting ambulatory blood pressure readings.  相似文献   
9.
Summary The effects of massive destruction of granule cells of the fascia dentata on the spatial and temporal firing characteristics of pyramidal cells in the CA1 and CA3 subfields of the hippocampus were examined in freely moving rats. Microinjections of the neurotoxin colchicine were made at a number of levels along the septo-temporal axis of the dentate gyri of both hemispheres, resulting in destruction of over 75% of the granule cells. By contrast there was relatively little damage to the pyramidal cell fields. As assessed by three different behavioral tests, the colchicine treatment resulted in severe spatial learning deficits. Single units were recorded from the CA1 and CA3 subfields using the stereotrode recording method while the animals performed a forced choice behavioral task on the radial 8-arm maze. Considering the extent of damage to the dentate gyrus, which has hitherto been considered to be the main source of afferent information to the CA fields, there was remarkably little effect on the spatial selectivity of place cell discharge on the maze, as compared to recordings from control animals. There was, however, a change in the temporal firing characteristics of these cells, which was manifested primarily as an increase in the likelihood of burst discharge. The main conclusion derived from these findings is that most of the spatial information exhibited by hippocampal pyramidal cells is likely to be transmitted from the cortex by routes other than the traditional trisynaptic circuit. These routes may include the direct projections from entorhinal layers II and III to CA3 and CA1, respectively.  相似文献   
10.
One reason the electrophysiological correlates of hippocampal neurons are of interest is the possibility that they reflect their representational properties, presumably spatial/relational ones. Stable spatial representations, based on activity of ensembles of hippocampal place cells, initially develop through a series of short-episodic spatial tunings. Hence these short-episodic spatial tunings are important for understanding the establishment of stable place fields. Studies of age-related changes in place cell activities traditionally focus on place fields. In the present study, we characterized the short-episodic spatial tunings (1-min bins) of hippocampal CA1 place cells of freely moving mice in a familiar cylinder arena, and compared these functions in young and old mice. Spatial tuning was expressed by spatial selectivity, which we found fluctuated across a 16-min recording session in both young and old mice. High spatial selectivity, which is mainly due to the low firing of a place cell out of the place field in young mice, was significantly higher in old mice. The high firing rate out of the place field was the main factor contributing to significantly lower spatial selectivity in old mice. In addition, young mice showed a broad peak in the spatial selectivity between 4 and 10 min. In contrast old mice showed no peak in the spatial selectivity during this time period. The stability of place fields after a 24-h interval was also lower in old mice than in young mice. The low spatial tuning and unstable place fields suggest that a hippocampal-based spatial representation was impaired in the old mice. Furthermore, we speculate that the age-related impairment in hippocampal inhibition system may be involved in the impaired spatial representation of hippocampal CA1 place cells in old mice. Electronic Publication  相似文献   
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