Over the last two decades, urban researchers have investigated how gender shapes gay and lesbian geographies in major post-industrial cities. These studies demonstrated that while gay men have often produced highly vi...
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Over the last two decades, urban researchers have investigated how gender shapes gay and lesbian geographies in major post-industrial cities. These studies demonstrated that while gay men have often produced highly visible territorial enclaves in inner-city areas, lesbian forms of territoriality at the urban scale have been relatively 'invisible' since their communities are constituted through social networks rather than commercial sites. Contrasting the patterns produced by these two populations in the inner-city areas of post-industrial cities during the 'queer' 1990s has created a gender-polarized and historically specific interpretation of their patterns of territoriality and visibility that may differ significantly from those of earlier periods. This paper, therefore, provides a longrange historical geography of lesbians in a major metropolitan area through a case study of Montreal's lesbian bar cultures since 1950. The focus of the analysis is on the preconditions that led to the establishment of the city's lesbian commercial enclave in the 1980s and the factors that led to its decline in the 1990s. This case study, therefore, outlines the shifting character of lesbian territorial practices at the urban scale in Montreal since 1950. It illustrates that in Montreal lesbian territoriality and visibility have been strongly impacted by local neighbourhood dynamics, internal ideologies, and political and spatial relationships with gay men. Ultimately, these findings suggest that contemporary lesbian visibility at the urban scale may have been undermined by an increased identification with the 'queer' forms of community and their territorialization in Montreal's gay Village.
The physics of shallow gravity currents passing through a rotating channel at subcritical Froude number is investigated here with a series of idealized numerical experiments. It is found that the combined effects of f...
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The physics of shallow gravity currents passing through a rotating channel at subcritical Froude number is investigated here with a series of idealized numerical experiments. It is found that the combined effects of friction and rotation set up a complex transverse circulation that has some crucial implications for the entrainment process. A key component of this secondary circulation is a geostrophically balanced transverse jet in the interface that laterally drains fluid from the interface. This effect is shown to result in a strong cross-channel asymmetry and a spatial separation of the entrainment process: drained interfacial fluid is partly replaced by entrained ambient fluid on the deep side of the gravity current, whereas the downward mixing of buoyant fluid occurs on the shallow side. These results, closely corresponding to recent measurements in a shallow, channelized gravity current in the western Baltic Sea, illustrate that the description of entrainment as a strictly vertical mixing process with the help of local bulk parameters like the Froude number is not generally applicable in rotating gravity currents.
Our objective was to propose a strategy to screen HIV-infected African people for biological immunodeficiency easily. In a cross-sectional study, we analysed the patterns of diseases and of CD4 counts among 266 HIV-in...
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Our objective was to propose a strategy to screen HIV-infected African people for biological immunodeficiency easily. In a cross-sectional study, we analysed the patterns of diseases and of CD4 counts among 266 HIV-infected adults. Peripheral facial paralysis and chronic cutaneo-mucous diseases were the earlier B-stage diseases. Pulmonary tuberculosis was close to B-stage diseases, and chronic diarrhoea was borderline between B and C stages. Cachexia was the most frequent C-stage symptom (47.8%). Ninety per cent of CDC-C stage people had CD4 counts below 350/mu l, whereas only 75% had CD4 counts below 200/mu l. Regression analysis identified the lymphocyte count, clinical stage and platelet count as predictors of CD4 count below 350/mu l. A simple score (lymphocyte count less than or equal to 2500/mu l and clinical stage greater than or equal to B) is proposed to determine this CD4 threshold (positive predictive value: 83%) and to determine those patients needing treatment to prevent wasting and opportunistic infections.
Cooled silicon IMPATT diodes for submillimeter-wave CW operation were investigated. Small-signal diode admittance was calculated, including the temperature effect, and liquid nitrogen cooled operation was tested in th...
Cooled silicon IMPATT diodes for submillimeter-wave CW operation were investigated. Small-signal diode admittance was calculated, including the temperature effect, and liquid nitrogen cooled operation was tested in the submillimeter-wave region. The oscillation frequency increase was observed in low junction temperature and output power characteristics were improved in 300 GHz and 400 GHz bands. At 412 GHz, an output power of 2.2 mW with 0.047% conversion efficiency and at 295 GHz, 4.5 mW with 0.13%, were obtained by ion implanted p+ -n-n+ SDR diodes. The highest oscillation frequency observed was 430 GHz.
In this article we report the seed-assisted growth of epitaxial ZnO nanorod (NR) arrays on (0001) plane sapphire substrates at low temperatures in aqueous solutions. The self-organized periodic ZnO NR rows with a fair...
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In this article we report the seed-assisted growth of epitaxial ZnO nanorod (NR) arrays on (0001) plane sapphire substrates at low temperatures in aqueous solutions. The self-organized periodic ZnO NR rows with a fairly constant separation were directly grown on bare sapphire surfaces, without the need for any complicated lithography or use of pre-patterned catalysts. The spatial ordering of the ZnO NRs was significantly influenced by the seed growth conditions and by the presence of a self-organized step structure on the annealed sapphire surface. In addition, the effect of the conditions employed to prepare the seeds, including growth parameters and post-growth annealing treatment, on the epitaxial relationship between the ZnO NRs and the sapphire substrate was systematically investigated by X-ray diffraction (XRD) measurements and transmission electron microscopy (TEM) observations. Post-growth annealing of the ZnO seeds changed the morphologies and crystallographic alignment of the generated ZnO nanostructures significantly, as a result of the formation of epitaxial spinel ZnAl2O4 interlayers, facilitated by zinc cation diffusion and solid state reactions at high temperature. (C) 2011 Elsevier B.V. All rights reserved.
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