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211.
This essay examines the recent controversy surrounding ‘Safe Schools', a federally-funded education program designed to reduce anti-lesbian, gay, bisexual, transgender and intersex (LGBTI) bullying in Australian schools. Although LGBTI students are known to experience homophobic, biphobic and transphobic verbal and physical abuse at school, opponents of Safe Schools have argued that the Program is both unnecessary and potentially harmful. In the essay, we argue that geographers have valuable contributions to make to this debate, particularly by revealing the ways in which sexuality and gender shape young people's experiences of school spaces. 相似文献
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213.
Development of seasonal hypoxia was studied weekly in the western narrows of Long Island Sound (WLIS) during the summers of 1992 and 1993 by measuring hydrographic properties, biological oxygen demand (BOD), biomass, production, and mortality of phytoplankton and bacterioplankton in the water column. Dissolved oxygen in bottom waters was low and variable during stratified periods (19–51% saturation), oscillating in and out of hypoxic conditions (defined as <3 mg O2 l−1 or 94 μM O2). Hypoxia was more prevalent in 1993 than in 1992, corresponding to greater water column stratification in 1993. Microbial BOD in bottom waters appeared to be fueled by delivery of autochthonous carbon from phytoplankton blooms rather than allochthonous carbon input. Phytoplankton production responded to elevated NH4 + concentrations, especially when the mixed layer was shallow. NH4 + concentrations generally varied as a function of the preceding week's rainfall (r2=0.765). Bacterial production did not covary with phytoplankton production, yet was closely correlated with particulate organic carbon, which was chlorophyll-rich. Results indicate that the timing and severity of hypoxia development are strongly coupled to allochthonous input of NH4 + after heavy precipitation. Observations illustrate for the first time that bottom waters in this system oscillate in and out of hypoxia on an almost weekly basis rather than sustain them over the entire stratified period. The frequency of these oscillations depends upon variations in nutrients, planktonic production and export, and bottom water ventilation. 相似文献
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215.
A critical test of a general circulation model is its performance on the regional scale. In this paper we examine the summer climatology of the CSIRO4 (4-layer) climate model over the Australian tropical region. The benchmark for the study is the positioning of the monsoon equatorial trough. We compare the CSIRO4 model climatology with the climatologies from the GFDL and GISS models and we report on the sensitivity of the position of the monsoon shear line and the strength of the monsoon westerly winds to the doubling of carbon dioxide in the atmosphere. The model results show that under the greenhouse scenario the monsoon is strengthened, but the average location of the monsoon shear line is not sensitive to the doubling of CO2.
Offprint requests to: BF Ryan 相似文献
216.
Tropical air-sea interaction in general circulation models 总被引:10,自引:0,他引:10
217.
James P. Howington Gordon A. McFeters James P. Barry James J. Smith 《Marine pollution bulletin》1992,25(9-12):324-327
The spatial distribution and movement of the sewage plume from McMurdo Station, Antarctica, was investigated in the ocean under the early summer ice. Samples of seawater were obtained via holes drilled through the ice and analysed for coliform bacteria. Ocean currents were also examined to determine their effect on the movement of the plume. High densities of coliform bacteria were found along the ca. 1 km shoreline of McMurdo Station and the plume extended 200–300 m seaward. The relocation of the outfall from a surface configuration to the subsurface (11 m deep) had little influence on the distribution of the plume that sometimes reached the seawater intake station, 400 m to the south. Ocean current measurements in the study area confirmed that, while the prevailing advection was to the north and away from the intake area, episodic reversals of flow at some current meter stations coincided with pulses of sewage that moved into the intake. These findings support the use of bacterial indicators as one means to map the distribution and movement of recent sewage contamination in cold (−1.8°C) seawater and provides evidence that the disposal and movement of domestic wastes in coastal polar environments deserves attention. 相似文献
218.
Graham A. Bonwick Philip Vas Peter R. Fielden John D. M. Gordon 《Marine pollution bulletin》1990,21(12):567-570
Liver extracts from three species of shark (Etmopterus spinax, Galeorhinus galeus, Scymnorhinus licha), were analysed using Differential Pulse Polarography. All three extracts gave significant polarographic responses, indicating the presence of cysteine containing proteins. On the basis of previous work, these proteins were considered to be metallothionein-like in nature. These results mark the first data on MT in natural populations of sharks and in mid- to deep-water species. 相似文献
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We evaluate the relationship between the hard X-ray photon spectrum and the flux of iron K emission in a thick-target electron bombardment model. Results are presented for various power-law hard X-ray spectra. We then apply these results to two events observed with the Hard X-Ray Burst Spectrometer and the K channel of the X-Ray Polychromator Bent Crystal Spectrometer on the Solar Maximum Mission satellite. For one of the events, on 29 March, 1980, at 09:18 UT, the K flux predicted for a thick-target non-thermal process is significant compared to the background fluorescent component, and the data are indeed consistent with an enhancement of the predicted amount. For the other event, on 14 October, 1980 at 06:09 UT, the hard X-ray spectrum is so steep that no significant Ka flux is predicted for this process, and no enhancement is seen. We conclude that the agreement between the predicted K flux and the observed magnitude of the K enhancement above the fluorescent background at the time of the large hard X-ray bursts lends support to a thick-target non-thermal interpretation of impulsive hard X-ray emission in solar flares. 相似文献