4 research outputs found
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Being held to account: Detainees’ perceptions of police body-worn cameras
Police organisations across the world are embracing body-worn video camera technology. The justification for this is to enhance public trust in police, provide transparency in policing activity, increase police accountability, reduce conflict between police and public, and to provide a police perspective of incidents and events. However, while the corpus of research into the efficacy and operational practicalities of police use of body-worn video cameras is developing, questions on some elements of their impact remain. The majority of scholarship has hitherto been evaluations focused on the impact of the cameras on police use of force and on the numbers of complaints against the police. Alternatively, this article explores body-worn video cameras from the perspective of police detainees, and specifically, detainees’ perceptions of the capacities of body-worn video cameras to deliver promised increased levels of accountability in policing. The article draws on a survey and research interviews with 907 police detainees across four Australian jurisdictions. While respondents largely support the use of body-worn video cameras they also identify a number of caveats. We conclude by suggesting that there are still impediments in body-worn video cameras to achieving the level of accountability promised by advocates and expected by the respondents
Influence of urban pollution on the production of organic particulate matter from isoprene epoxydiols in central Amazonia
The atmospheric chemistry of isoprene contributes to the production of a substantial mass fraction of the particulate matter (PM) over tropical forests. Isoprene epoxydiols (IEPOX) produced in the gas phase by the oxidation of isoprene under HO2-dominant conditions are subsequently taken up by particles, thereby leading to production of secondary organic PM. The present study investigates possible perturbations to this pathway by urban pollution. The measurement site in central Amazonia was located 4 to 6 h downwind of Manaus, Brazil. Measurements took place from February through March 2014 of the wet season, as part of the GoAmazon2014/5 experiment. Mass spectra of organic PM collected with an Aerodyne Aerosol Mass Spectrometer were analyzed by positive-matrix factorization. One resolved statistical factor (IEPOX-SOA factor) was associated with PM production by the IEPOX pathway. The IEPOX-SOA factor loadings correlated with independently measured mass concentrations of tracers of IEPOX-derived PM, namely C5-alkene triols and 2-methyltetrols (R = 0. 96 and 0.78, respectively). The factor loading, as well as the ratio f of the loading to organic PM mass concentration, decreased under polluted compared to background conditions. For an increase in NOy concentration from 0.5 to 2 ppb, the factor loading and f decreased by two to three fold. Overall, sulfate concentration explained 37 % of the variability in the factor loading. After segregation of factor loading into subsets based on NOy concentration, the sulfate concentration explained up to 75 % of the variability. Considering both factors, the data sets show that the suppressing effects of increased NO concentrations dominated over the enhancing effects of higher sulfate concentrations. The pollution from Manaus elevated NOy concentrations more significantly than sulfate concentrations relative to background conditions. In this light, increased emissions of nitrogen oxides, as anticipated for some scenarios of Amazonian economic development, could significantly alter pathways of PM production that presently prevail over the tropical forest, implying changes to air quality and regional climate.</html