Conifer needles bioaccumulate atmospheric pollutants, including trace metals, and may be used to monitor variations in atmospheric concentration. Needles were analyzed to determine whether a correlation exists between...Conifer needles bioaccumulate atmospheric pollutants, including trace metals, and may be used to monitor variations in atmospheric concentration. Needles were analyzed to determine whether a correlation exists between elevations and trace metal concentrations in proximity to roadways and other non-point sources. Composite samples of white spruce (Picea glauca) and balsam fir (Abies balsamea) needles were collected along hillsides in eastern and western Calgary, respectively. A combined total of 11 sites was sampled along two transects of increasing elevation. Qualitative and quantitative analysis of trace metal concentrations was completed using inductively coupled plasma-mass spectrometry (ICP-MS) and synthesized using regression analysis. The concentrations of cobalt, nickel, and calcium in the samples were found to exhibit a significant (P < 0.05) relationship with respect to elevation and proximity to roadways.展开更多
Introduction: Sexual behaviour among gay and other men who have sex with men (GMSM) is influenced by the shared understanding of HIV/STI risk and peer norms regarding sexual behaviour. However, there is little researc...Introduction: Sexual behaviour among gay and other men who have sex with men (GMSM) is influenced by the shared understanding of HIV/STI risk and peer norms regarding sexual behaviour. However, there is little research evidence to support this relationship. The unique geographic spread of Australian communities, the history of Australian HIV epidemic and the different patterns in risky sexual practices and HIV diagnoses across Australia present an opportunity to explore the role of social norms and GMSM behaviours in shaping different patterns of HIV epidemics. We describe the protocol of the study of contemporary norms in networks and communities of GMSM (CONNECT) which investigates gay community behavioural norms and practices. Methods: CONNECT is aimed to 1) identify the patterns of connections between individuals in GMSM communities and assess how they shape HIV-related behaviours;2) describe the relationship between social norms and sexual practices;and 3) compare the norms and patterns of behaviour in geographically and epidemiologically distinct GMSM populations in three Australian states New South Wales, Victoria and Western Australia, in order to identify local community norms and barriers to effective HIV prevention. This quantitative cross-sectional study uses respondent-driven sampling (RDS) for recruitment. Results: Analyses will be carried out on individual and community level and will investigate the relationship between community-level behavioural norms and associated practices of individuals. Conclusion: CONNECT is anticipated to inform HIV prevention services to better target and increase the effectiveness of the current health promotion for GMSM in the context of increasing HIV/STI incidence.展开更多
Recollision physics and attosecond pulse generation meld the precision of optics with collision physics.As a follow-up to our previous work,we reveal a new direction for the study of electronic structure and multielec...Recollision physics and attosecond pulse generation meld the precision of optics with collision physics.As a follow-up to our previous work,we reveal a new direction for the study of electronic structure and multielectron dynamics by exploiting the collision-physics nature of recollision.We show experimentally that,by perturbing recollision trajectories with an infrared field,photorecombination time delays can be measured entirely optically using the Cooper minimum in argon as an example.In doing so,we demonstrate the relationship between recollision trajectories and the transition moment coupling the ground and continuum states.In particular,we show that recollision trajectories are influenced by their parent ion,while it is commonly assumed they are not.Our work paves the way for the entirely optical measurement of ultrafast electron dynamics and photorecombination delays due to electronic structure,multielectron interaction,and strong-field-driven dynamics in complex molecular systems and correlated solid-state systems.展开更多
文摘Conifer needles bioaccumulate atmospheric pollutants, including trace metals, and may be used to monitor variations in atmospheric concentration. Needles were analyzed to determine whether a correlation exists between elevations and trace metal concentrations in proximity to roadways and other non-point sources. Composite samples of white spruce (Picea glauca) and balsam fir (Abies balsamea) needles were collected along hillsides in eastern and western Calgary, respectively. A combined total of 11 sites was sampled along two transects of increasing elevation. Qualitative and quantitative analysis of trace metal concentrations was completed using inductively coupled plasma-mass spectrometry (ICP-MS) and synthesized using regression analysis. The concentrations of cobalt, nickel, and calcium in the samples were found to exhibit a significant (P < 0.05) relationship with respect to elevation and proximity to roadways.
文摘Introduction: Sexual behaviour among gay and other men who have sex with men (GMSM) is influenced by the shared understanding of HIV/STI risk and peer norms regarding sexual behaviour. However, there is little research evidence to support this relationship. The unique geographic spread of Australian communities, the history of Australian HIV epidemic and the different patterns in risky sexual practices and HIV diagnoses across Australia present an opportunity to explore the role of social norms and GMSM behaviours in shaping different patterns of HIV epidemics. We describe the protocol of the study of contemporary norms in networks and communities of GMSM (CONNECT) which investigates gay community behavioural norms and practices. Methods: CONNECT is aimed to 1) identify the patterns of connections between individuals in GMSM communities and assess how they shape HIV-related behaviours;2) describe the relationship between social norms and sexual practices;and 3) compare the norms and patterns of behaviour in geographically and epidemiologically distinct GMSM populations in three Australian states New South Wales, Victoria and Western Australia, in order to identify local community norms and barriers to effective HIV prevention. This quantitative cross-sectional study uses respondent-driven sampling (RDS) for recruitment. Results: Analyses will be carried out on individual and community level and will investigate the relationship between community-level behavioural norms and associated practices of individuals. Conclusion: CONNECT is anticipated to inform HIV prevention services to better target and increase the effectiveness of the current health promotion for GMSM in the context of increasing HIV/STI incidence.
基金United States Air Force Office of Scientific Research(award no.FA9550-16-1-0109)with contributions from the Canada Foundation for Innovation,the Canada Research Chairs Program,Canada's Natural Sciences and Engineering Research Council,and the National Research Council of Canada.
文摘Recollision physics and attosecond pulse generation meld the precision of optics with collision physics.As a follow-up to our previous work,we reveal a new direction for the study of electronic structure and multielectron dynamics by exploiting the collision-physics nature of recollision.We show experimentally that,by perturbing recollision trajectories with an infrared field,photorecombination time delays can be measured entirely optically using the Cooper minimum in argon as an example.In doing so,we demonstrate the relationship between recollision trajectories and the transition moment coupling the ground and continuum states.In particular,we show that recollision trajectories are influenced by their parent ion,while it is commonly assumed they are not.Our work paves the way for the entirely optical measurement of ultrafast electron dynamics and photorecombination delays due to electronic structure,multielectron interaction,and strong-field-driven dynamics in complex molecular systems and correlated solid-state systems.
