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ABSTRACT

Smoke from burning biomass is an important source of fine particulate matter (PM2.5), but the health risks may not be fully captured by the Canadian Air Quality Health Index (AQHI). In May 2018, the province of British Columbia launched an evidence-based amendment (AQHI-Plus) to improve AQHI performance for wildfire smoke, but the AQHI-Plus was not developed or tested on data from the residential woodsmoke season. This study assesses how the AQHI and AQHI-Plus are associated with acute health outcomes during the cooler seasons of 2010–2017 in British Columbia, Canada. Monthly and daily patterns of temperature and PM2.5 concentrations were used to identify Local Health Areas (LHAs) that were impacted by residential woodsmoke. The effects of the AQHI and AQHI-Plus on five acute health outcomes (including non-accidental mortality, outpatient physician visits, and medical dispensations for cardiopulmonary conditions) were estimated using generalized linear mixed effect models with Poisson distributions adjusted for long- and short-term temperature trends. Values of the Akaike information criterion (AIC) were compared to evaluate whether the AQHI or AQHI-Plus was better fitted to each health outcome. Eleven LHAs were categorized as woodsmoke-impacted. In these LHAs, the AQHI and AQHI-Plus associations with acute health outcomes were sensitive to temperature adjustments. After temperature adjustments, the most consistent associations were observed for the two asthma-specific outcomes where the AQHI-Plus was better fitted than the AQHI. The improved performance of the AQHI-Plus for susceptible populations with asthma is consistent between communities impacted by residential woodsmoke and wildfire smoke.

Implications: Canada’s Air Quality Health Index (AQHI) is a three pollutant index used to communicate the short term health impact of degraded air quality. As fine particulate matter (PM2.5) is the lowest weighted pollutant in the AQHI, the index is poorly reflective of woodsmoke impacts. The present analysis found that an AQHI amendment developed for improved sensitivity to PM2.5 during wildfire seasons (AQHI-Plus) is also more predictive of acute asthma-related health outcomes in communities impacted by residential woodsmoke. The BC Ministry of Environment and Climate Change Strategy has piloted the AQHI-Plus year-round. Other jurisdictions should consider whether their air quality indices are reflective of the risks posed by woodsmoke.  相似文献   
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Through interviews and mail surveys, Ohio potato (Solanum tuberosum) growers were surveyed concerning their willingness to adopt three cultural controls being developed for management of the Colorado potato beetle, Leptinotarsa decemlineata (Say), which had become increasingly difficult to control. The principal objective of the research was to obtain a deeper understanding of how farmers make decisions to adopt or not adopt new techniques and how these decisions are related to farmers' educational backgrounds and the way they currently manage their farms. The three cultural management options emphasized ecological approaches to habitat management rather than ecologically disruptive chemical control: (1) using host plants in overwintering sites to slow the spring movement of the beetles to potato fields, (2) using larger potato plants at field borders than in the center of the field as a spring trap crop, and (3) concentrating beetles in relatively small undefoliated areas to be killed with heat in late summer. Most respondents would not adopt these alternative pest management strategies, mainly because they perceived an unsatisfactory trade-off between logistic difficulties and expenses and population suppression they would achieve compared with traditional chemical control measures. Education correlated positively and experience in farming negatively with the willingness to try new pest management techniques. Additionally, growers responding more negatively to questions regarding integrated pest management strategies were more willing to experiment with the alternative techniques, a result attributed to either the survey design or an indication of experience with the more intensive management effort required for integrated pest management. This profile of potential innovators should be used by researchers to establish partnerships with farmers that could assist with both the research and development of new farming techniques and the adoption of successful systems by other farmers.  相似文献   
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We evaluate a proposal to double sockeye salmon production from the Fraser River and conclude that significant changes will be required to current management processes, particularly the way available catch is allocated, if the plan is to be consistent with five major principles embodied in the concept of sustainable development. Doubling sockeye salmon production will not, in itself, increase economic equity either regionally or globally. Developing nations may actually be hindered in their attempts to institute other, nonsalmon fisheries in the North Pacific Ocean as a result of the possible interception of salmon. Further, other users of the Fraser River basin will have to forgo opportunities so that salmon habitat can be conserved. If doubling sockeye salmon production is to meet the goal of doing more with less, it will be necessary to develop more efficient technologies to harvest the fish. If increasing salmon production is to reflect the integration of environmental and economic decision making at the highest level, then a serious attempt must be made to incorporate environmental assets into national economic accounting. Finally, to promote biodiversity and cultural self-sufficiency within the Fraser River basin, it will be important to safeguard the small, less-productive salmon stocks as well as the large ones and to allocate a substantial portion of the increased production to the Native Indian community.  相似文献   
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Epidemiological studies continue to reveal the enduring impact of exposures to environmental chemicals on human physiology, including our reproductive health. Phthalates, a well characterized class of endocrine disrupting chemicals and commonly utilized plasticizers, are among one of the many toxicants ubiquitously present in our environment. Phthalate exposure has been linked to increases in the rate of human aneuploidy, a phenomenon that is detected in 0.3% of livebirths resulting in genetic disorders including trisomy 21, approximately 4% of stillbirths, and over 35% of miscarriages. Here we review recent epidemiological and experimental studies that have examined the role that phthalates play in germline dysfunction, including increases in apoptosis, oxidative stress, DNA damage, and impaired genomic integrity, resulting in aneuploidy. We will further discuss subject variability, as it relates to diet and polymorphisms, and the sexual dimorphic effects of phthalate exposure, as it relates to sex-specific targets. Lastly, we discuss some of the conserved effects of phthalate exposure across humans, mammalian models and nonmammalian model organisms, highlighting the importance of using model organisms to our advantage for chemical risk assessment and unveiling potential mechanisms that underlie phthalate-induced reproductive health issues across species.  相似文献   
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The exceptionally rare transition to quadrupedalism from bipedal ancestors occurred on three independent occasions in ornithischian dinosaurs. The possible driving forces behind these transitions remain elusive, but several hypotheses—including the development of dermal armour and the expansion of head size and cranial ornamentation—have been proposed to account for this major shift in stance. We modelled the position of the centre of mass (CoM) in several exemplar ornithischian taxa and demonstrate that the anterior shifts in CoM position associated with the development of an enlarged skull ornamented with horns and frills for display/defence may have been one of the drivers promoting ceratopsian quadrupedality. A posterior shift in CoM position coincident with the development of extensive dermal armour in thyreophorans demonstrates this cannot have been a primary causative mechanism for quadrupedality in this clade. Quadrupedalism developed in response to different selective pressures in each ornithischian lineage, indicating different evolutionary pathways to convergent quadrupedal morphology.  相似文献   
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Determining the magnitude of homing behaviour within migratory fish species is essential for their conservation and management. We tested for population genetic structuring in the anadromous alosines, Alosa alosa and A. fallax fallax, to establish fidelity of stocks to spawning grounds in the United Kingdom and Ireland. Considerable genetic differences were present among populations of both species, suggesting strong fidelity to breeding grounds and compatible with homing to natal origins. Moreover, the genetic structure of A. fallax fallax showed a clear pattern of isolation-by-distance, consistent with breeding populations exchanging migrants primarily with neighbouring populations. Spatial genetic differences were on average much greater than temporal differences, indicating relatively stable genetic structure. Comparing anadromous A. fallax fallax populations to the landlocked Killarney shad subspecies, A. fallax killarnensis (Ireland), demonstrated a long history of separation. These results demonstrating regional stock structure within the British Isles will inform practical management of stocks and their spawning habitats.  相似文献   
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The oxidation state of chromium in contaminated soils is an important indicator of toxicity and potential mobility. Chromium in the hexavalent state is highly toxic and soluble, whereas the trivalent state is much less toxic and relatively insoluble. A laboratory study investigated the impact of growing plants and supplemental organic matter on chromium transport in soil. Plants alone had no appreciable effect on the chromium oxidation state in soil. Soil columns with higher organic content were associated with lower ratios of chromate:total chromium than the columns with lower organic matter. Analyses of column leachate, plant biomass, and soil indicate that more chromium leaching occurred in the vegetated, low organic columns. Retention of Cr in the soils was correlated to the Cr(III) content. Plant uptake of chromium accounted for less than 1% of the chromium removed from the soil. Overall, the addition of organic matter had the strongest influence on chromium mobility.  相似文献   
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