999 resultados para Stokes parameters


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Traffic emissions are an important contributor to ambient air pollution, especially in large cities featuring extensive and high density traffic networks. Bus fleets represent a significant part of inner city traffic causing an increase in exposure to general public, passengers and drivers along bus routes and at bus stations. Limited information is available on quantification of the levels, and governing parameters affecting the air pollution exposure at bus stations. The presented study investigated the bus emissions-dominated ambient air in a large, inner city bus station, with a specific focus on submicrometer particles. The study’s objectives were (i) quantification of the concentration levels; (ii) characterisation of the spatio-temporal variation; (iii) identification of the parameters governing the emissions levels at the bus station and (iv) assessment of the relationship between particle concentrations measured at the street level (background) and within the bus station. The results show that up to 90% of the emissions at the station are ultrafine particles (smaller than 100 nm), with the concentration levels up to 10 times the value of urban ambient air background (annual) and up to 4 times the local ambient air background. The governing parameters affecting particle concentration at the station were bus flow rate and meteorological conditions (wind velocity). Particle concentration followed a diurnal trend, with an increase in the morning and evening, associated with traffic rush hours. Passengers’ exposure could be significant compared to the average outdoor and indoor exposure levels.

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This study aimed to describe wandering using new parameters and to evaluate parameters as a function of cognitive impairment and mobility. Forty-four wanderers in long-term care settings were videotaped 12 times. Rate and duration of wandering episodes were plotted and used to derive parameters from values above and below case medians, proportion of hours wandering, and time of day. Participants wandered during 47% of observations; on average, the hourly rate was 4.3 episodes, the peak hourly rate was 18 episodes, and the peak hourly duration was 19.9 minutes. Mini-Mental State Examination (MMSE) scores was negatively correlated with overall duration and number of observations during which duration exceeded 15 minutes per hour, was positively correlated with number of observations without wandering, and was not significantly correlated with rate-related parameters. Mobility correlated positively with rate and duration parameters. Interaction of MMSE score and mobility was the strongest predictor of wandering duration. Parameters derived from repeated measures provide a new view of daytime wandering and insight into relationships between MMSE score and mobility status with specific parameters of wandering.

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Intimate partner violence (IPV) is not only a problem for heterosexual couples. Although research in the area is beset by methodological and definitional problems, studies generally demonstrate that IPV also affects those who identify as non-heterosexual; that is, those sexualities that are typically categorized as lesbian, gay, bisexual, transgender, or intersex (LGBTI). IPV appears to be at least as prevalent in LGBTI relationships as it is in heterosexual couples, and follows similar patterns (e.g. Australian Research Centre on Sex, Health and Society 2006; Donovan et al. 2006; Chan 2005; Craft and Serovich 2005; Burke et al. 2002; Jeffries and Ball 2008; Kelly and Warshafsky 1987; Letellier 1994; Turrell 2000; Ristock 2003; Vickers 1996). There is, however, little in the way of specific community or social services support available to either victims or perpetrators of violence in same-sex relationships (see Vickers 1996). In addition, there are important differences in the experience of IPV between LGBTI and non-LGBTI victims, and even among LGBTI individuals; for example, among transgender populations (Chan 2005), and those who are HIV sero-positive (Craft and Serovich 2005). These different experiences of IPV include the use of HIV and the threat of “outing” a partner as tools of control, as just two examples (Jeffries and Ball 2008; Salyer 1999; WA Government 2008b). Such differences impact on how LGBTI victims respond to the violence, including whether or not and how they seek help, what services they are able to avail themselves of, and how likely they are to remain with, or return to, their violent partners (Burke et al. 2002). This chapter explores the prevalent heteronormative discourses that surround IPV, both within the academic literature, and in general social and government discourses. It seeks to understand how same-sex IPV remains largely invisible, and suggests that these dominant discourses play a major role in maintaining this invisibility. In many respects, it builds on work by a number of scholars who have begun to interrogate the criminal justice and social discourses surrounding violent crime, primarily sexual violence, and who problematize these discourses (see for example Carmody 2003; Carmody and Carrington 2000; Marcus 1992). It will begin by outlining these dominant discourses, and then problematize these by identifying some of the important differences between LGBTI IPV and IPV in heterosexual relationships. In doing so, this chapter will suggest some possible reasons for the silence regarding IPV in LGBTI relationships, and the effects that this can have on victims. Although an equally important area of research, and another point at which the limitations of dominant social discourses surrounding IPV can be brought to light, this chapter will not examine violence experienced by heterosexual men at the hands of their intimate female partners. Instead, it will restrict itself to IPV perpetrated within same-sex relationships.