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In 2004, the authors convened a session entitled ‘Public Anthropology’ at the Australian Anthropology Society's annual conference. The session examined the development of a specific stream of public anthropology in the USA and Britain and its articulation by writers such as Robert Borofsky in the aftermath of the Yanomami controversy and Richard Werbner in the African context. In pursuing this discussion, we identify three key characteristics that distinguish public anthropology: the broader application of ethnography to urgent and political social issues in a way that shows the profoundly relational nature of current crises to historical, political and local events and forces; a focus on this approach as a central aspect of training, particularly at the postgraduate level; and an active and accessible engagement in public discussion and debate. We present a short case study from Skidmore's research on disease, suffering and the health system in Burma to illustrate ways in which a public anthropology approach could represent the current health crisis in Burma in an effective manner. Drawing also on the work of our fellow panellists, we argue for the timeliness of the development of a public anthropology stream in Australia and for the deliberate inclusion of public anthropology in the Australian Anthropology Society's mandate.  相似文献   
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The algal flagellate Euglena grown photoautotrophically in L:D 3:3 displays a circadian rhythm of cell division. Oscillatory models for cell cycle (CDC) control (particularly those of the limit cycle variety) include the property of phase perturbation, or resetting. This prediction has been tested in synchronous cultures in which the free-running rhythm has been scanned by 3-hr light signals. A strong (Type 0) phase response curve (PRC), yielding both advances and delays as great as 15 hr, has been derived. A second prediction of the limit cycle model is that there exists a pulse of a critical intensity, which, if given at one specific phase of the rhythm (the singularity point), should result in a phaseless, motionless state in which the rhythmicity disappears. Such a point has been found in Euglena in the late subjective night for light pulses having an intensity ranging from 40 to 700 Ix. Finally, circadian oscillators typically display temperature-compensated period lengths within the physiological range of steady-state temperatures, although the length of the CDC is commonly thought to be highly temperature dependent. We have found that over a range of at least 10°C, the period of the division rhythm is only slightly affected, exhibiting a Q10 of about 1.05-1.20. These observations, therefore, collectively implicate a circadian oscillator in the control of the CDC.  相似文献   
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A temperature-synchronized, semi-continuous culture and monitoring system is described, with results from use of the system for autotrophically growing Euglena. Outflow from the culture vessel consists of measured samples taken automatically at 2-hour intervals and fixed for later counting. Inflow is by siphon feed, which restores the culture level after each sampling. The interpretation of growth curves obtained from such cultures is discussed from the viewpoint, of division synchrony and cell cycle studies, and some general comparisons are made between batch and continuous cultures for such studies.  相似文献   
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To maximize the effectiveness of conservation interventions, it is crucial to have an understanding of how intraspecific variation determines the relative importance of potential limiting factors. For bird populations, limiting factors include nest‐site availability and foraging resources, with the former often addressed through the provision of artificial nestboxes. However, the effectiveness of artificial nestboxes depends on the relative importance of nest‐site vs. foraging resource limitations. Here, we investigate factors driving variation in breeding density, nestbox occupation and productivity in two contrasting study populations of the European Roller Coracias garrulus, an obligate cavity‐nesting insectivorous bird. Breeding density was more than four times higher at the French study site than at the Latvian site, and there was a positive correlation between breeding density (at the 1‐km2 scale) and nest‐site availability in France, whereas there was a positive correlation between breeding density and foraging resource availability in Latvia. Similarly, the probability of a nestbox being occupied increased with predicted foraging resource availability in Latvia but not in France. We detected no positive effect of foraging resource availability on productivity at either site, with most variation in breeding success driven by temporal effects: a seasonal decline in France and strong interannual fluctuations in Latvia. Our results indicate that the factors limiting local breeding density can vary across a species' range, resulting in different conservation priorities. Nestbox provisioning is a sufficient short‐term conservation solution at our French study site, where foraging resources are typically abundant, but in Latvia the restoration of foraging habitat may be more important.  相似文献   
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This study tested the hypothesis that the response of corals to temperature and pCO 2 is consistent between taxa. Juvenile massive Porites spp. and branches of P. rus from the back reef of Moorea were incubated for 1 month under combinations of temperature (29.3 °C and 25.6 °C) and pCO 2 (41.6 Pa and 81.5 Pa) at an irradiance of 599 μmol quanta m?2 s?1. Using microcosms and CO2 gas mixing technology, treatments were created in a partly nested design (tanks) with two between‐plot factors (temperature and pCO 2), and one within‐plot factor (taxon); calcification was used as a dependent variable. pCO 2 and temperature independently affected calcification, but the response differed between taxa. Massive Porites spp. was largely unaffected by the treatments, but P. rus grew 50% faster at 29.3 °C compared with 25.6 °C, and 28% slower at 81.5 Pa vs. 41.6 Pa CO2. A compilation of studies placed the present results in a broader context and tested the hypothesis that calcification for individual coral genera is independent of pH, [HCO3 ?], and [CO3 2?]. Unlike recent reviews, this analysis was restricted to studies reporting calcification in units that could be converted to nmol CaCO3 cm?2 h?1. The compilation revealed a high degree of variation in calcification as a function of pH, [HCO3 ?], and [CO3 2?], and supported three conclusions: (1) studies of the effects of ocean acidification on corals need to pay closer attention to reducing variance in experimental outcomes to achieve stronger synthetic capacity, (2) coral genera respond in dissimilar ways to pH, [HCO3 ?], and [CO3 2?], and (3) calcification of massive Porites spp. is relatively resistant to short exposures of increased pCO 2, similar to that expected within 100 y.  相似文献   
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