High-resolution spatial and spatiotemporal modelling of air pollution using fixed site and mobile monitoring in a Canadian city.

The development of high-resolution spatial and spatiotemporal models of air pollutants is essential for exposure science and epidemiological applications. While fixed-site sampling has conventionally provided input data for statistical predictive models, the evolving mobile monitoring method offers improved spatial resolution, ideal for measuring pollutants with high spatial variability such as ultrafine particles (UFP). The Quebec Air Pollution Exposure and Epidemiology (QAPEE) study measured and modelled the spatial and spatiotemporal distributions of understudied pollutants, such as UFPs, black carbon (BC), and brown carbon (BrC), along with fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3) in Quebec City, Canada. We conducted a combined fixed-site (NO2 and O3) and mobile monitoring (PM2.5, BC, BrC, and UFPs) campaign over 10-months. Mobile monitoring routes were monitored on a weekly basis between 8am-10am and designed using location/allocation modelling. Seasonal fixed-site sampling campaigns captured continuous 24-h measurements over two-week periods. Generalized Additive Models (GAMs), which combined data on pollution concentrations with spatial, temporal, and spatiotemporal predictor variables were used to model and predict concentration surfaces. Annual models for PM2.5, NO2, O3 as well as seven of the smallest size fractions in the UFP range, had high out of sample predictive accuracy (range r2: 0.54-0.86). Varying spatial patterns were observed across UFP size ranges measured as Particle Number Counts (PNC). The monthly spatiotemporal models for PM2.5 (r2 = 0.49), BC (r2 = 0.27), BrC (r2 = 0.29), and PNC (r2 = 0.49) had moderate or moderate-low out of sample predictive accuracy. We conducted a sensitivity analysis and found that the minimum number of 'n visits' (mobile monitoring sessions) required to model annually representative air pollution concentrations was between 24 and 32 visits dependent on the pollutant. This study provides a single source of exposure models for a comprehensive set of air pollutants in Quebec City, Canada. These exposure models will feed into epidemiological research on the health impacts of ambient UFPs and other pollutants

Prairie strips improve biodiversity and the delivery of multiple ecosystem services from corn–soybean croplands

Loss of biodiversity and degradation of ecosystem services from agricultural lands remain important challenges in the United States despite decades of spending on natural resource management. To date, conservation investment has emphasized engineering practices or vegetative strategies centered on monocultural plantings of nonnative plants, largely excluding native species from cropland. In a catchment-scale experiment, we quantified the multiple effects of integrating strips of native prairie species amid corn and soybean crops, with prairie strips arranged to arrest run-off on slopes. Replacing 10% of cropland with prairie strips increased biodiversity and ecosystem services with minimal impacts on crop production. Compared with catchments containing only crops, integrating prairie strips into cropland led to greater catchment-level insect taxa richness (2.6-fold), pollinator abundance (3.5-fold), native bird species richness (2.1-fold), and abundance of bird species of greatest conservation need (2.1-fold). Use of prairie strips also reduced total water runoff from catchments by 37%, resulting in retention of 20 times more soil and 4.3 times more phosphorus. Corn and soybean yields for catchments with prairie strips decreased only by the amount of the area taken out of crop production. Social survey results indicated demand among both farming and nonfarming populations for the environmental outcomes produced by prairie strips. If federal and state policies were aligned to promote prairie strips, the practice would be applicable to 3.9 million ha of cropland in Iowa alone

Spatial variations in ambient ultrafine particle concentrations and the risk of incident prostate cancer: A case-control study

Background Diesel exhaust contains large numbers of ultrafine particles (UFPs, <0.1 µm) and is a recognized human carcinogen. However, epidemiological studies have yet to evaluate the relationship between UFPs and cancer incidence. Methods We conducted a case-control study of UFPs and incident prostate cancer in Montreal, Canada. Cases were identified from all main Francophone hospitals in the Montreal area between 2005 and 2009. Population controls were identified from provincial electoral lists of French Montreal residents and frequency-matched to cases using 5-year age gr

The Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort study: Assessment of environmental exposures

The Canadian Healthy Infant Longitudinal Development birth cohort was designed to elucidate interactions between environment and genetics underlying development of asthma and allergy. Over 3600 pregnant mothers were recruited from the general population in four provinces with diverse environments. The child is followed to age 5 years, with prospective characterization of diverse exposures during this critical period. Key exposure domains include indoor and outdoor air pollutants, inhalation, ingestion and dermal uptake of chemicals, mold, dampness, biological allergens, pets and pests, housing structure, and living behavior, together with infections, nutrition, psychosocial environment, and medications. Assessments of early life exposures are focused on those linked to inflammatory responses driven by the acquired and innate immune systems. Mothers complete extensive environmental questionnaires including time-activity behavior at recruitment and when the child is 3, 6, 12, 24, 30, 36, 48, and 60 months old. House dust collected during a thorough home assessment at 3–4 months, and biological specimens obtained for multiple exposure-related measurements, are archived for analyses. Geo-locations of homes and daycares and land-use regression for estimating traffic-related air pollution complement time-activity-behavior data to provide comprehensive individual exposure profiles. Several analytical frameworks are proposed to address the many interacting exposure variables and potential issues of co-linearity in this complex data set

Experiences of lifestyle change among women with gestational diabetes mellitus (GDM): A behavioural diagnosis using the COM-B model in a low-income setting

Lifestyle change can reduce the risk of developing type 2 diabetes among women with prior gestational diabetes mellitus (GDM). While understanding women’s lived experiences and views around GDM is critical to the development of behaviour change interventions to reduce this risk, few studies have addressed this issue in low- and middle- income countries. The aim of the study was to explore women’s lived experiences of GDM and the feasibility of sustained lifestyle modification after GDM in a low-income setting

Policies and clinical practices relating to the management of gestational diabetes mellitus in the public health sector, South Africa – a qualitative study

BACKGROUND: Women with a prior gestational diabetes have an increased lifetime risk of developing type 2 diabetes. Although post-partum follow-up for GDM women is essential to prevent progression to type 2 diabetes, it is poorly attended. The need for health systems interventions to support postpartum follow-up for GDM women is evident, but there is little knowledge of actual current practice. The aim of this study was to explore current policies and clinical practices relating to antenatal and post-natal care for women with GDM in South Africa, as well as health sector stakeholders’ perspectives on the barriers to – and opportunities for – delivering an integrated mother - baby health service that extends beyond the first week post-partum, to the infant’s first year of life. METHODS: Following a document review of policy and clinical practice guidelines, in-depth interviews were conducted with 11 key informants who were key policy makers, health service managers and clinicians working in the public health services in South Africa’s two major cities (Johannesburg and Cape Town). Data were analysed using qualitative content analysis procedures. RESULTS: The document review and interviews established that it is policy that health services adhere to international guidelines for GDM diagnosis and management, in addition to locally developed guidelines and protocols for clinical practice. All key informants confirmed that lack of postpartum follow-up for GDM women is a significant problem. Health systems barriers include fragmentation of care and the absence of standardised postnatal care for post-GDM women. Key informants also raised patient - related challenges including lack of perceived future risk of developing type 2 diabetes and non-attendance for postpartum follow up, as barriers to postnatal care for GDM women. All participants supported integrated primary health services but cautioned against overloading health workers. CONCLUSION: Although there is alignment between international guidelines, local policy and reported clinical practice in the management of GDM, there is a gap in continuation of care in the postpartum period. Health systems interventions that support and facilitate active follow-up for women with prior GDM are needed if high rates of progression to type 2 diabetes are to be avoided

The Effects of Nitrogen Fertilization on Water Use by Crested Wheatgrass

The application of N fertilizer to crested wheatgrass on a dry rangeland site increased yields substantially. In the early part of the growing season when moisture was not limiting, soil moisture was withdrawn from the fertilized site at a higher rate than from the unfertilized plots. At later periods in the growing season the soil water potential curves paralleled each other with the fertilized crop growing under conditions of lower soil water potential. The decreased soil water potential was confirmed when the actual evapotranspiration, as measured by the energy balance method, was examined. The data indicate that for a period following rapid growth in the spring, the evapotranspiration of the fertilized block was less than that of the unfertilized. The soil water potential data indicate that seasonal evapotranspiration was slightly higher on the fertilized plot than on the unfertilized. The water use efficiency, in terms of biomass produced per unit of water used, was much greater for fertilized crested wheatgrass and resulted in increased yields.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Alkaloid Levels in Reed Canarygrass Grown on Wet Meadows in British Columbia

Hordenine, gramine, and 5-methoxy-N-methyltryptamine (5MMT) were identified as the major basic alkaloids in reed canarygrass grown on wet meadows in Interior British Columbia. The concentrations of these anti-quality constituents, determined sequentially at four field locations, were exceptionally low compared with levels found for reed canarygrass grown under growth room conditions. Under field conditions, for example, 5MMT levels did not exceed 250 micrograms/gram (dry wt), whereas a peak level of 4,250 micrograms/gram 5MMT was recorded from the growth room. Depressed alkaloid levels under wet meadow field conditions were observed in all varieties tested including two experimental varieties, one registered variety, and a commercial type. Low alkaloid levels on wet meadows appeared to coincide with fewer types of alkaloids: 5-methoxy-N, N-dimethyltryptamine (5DMT) was not detected under field conditions but it was present in all reed canarygrass samples analyzed from the growth room. Field applications of fertilizer (NPK) appeared to have marginal effects on alkaloid levels. On wet meadows the trends indicated that gramine and 5MMT concentrations increased toward the end of the growing season, but low total alkaloid levels were still maintained. The factor of soil moisture stress is reviewed in relation to alkaloid levels in reed canarygrass. Recently developed thin layer chromatography (TLC) scanning procedures were used to determine concentrations of gramine and 5MMT. New TLC fluorescence methods were devised for the quantitative determination of hordenine and 5DMT in reed canarygrass.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Effects of feeding high molybdenum hay to mature beef steers

A 3X3 latin square design experiment was used to study the effects of feeding high molybdenum (Mo) hay, from Highland Valley Copper, to three cannulated Hereford steers. Supplement treatments were; no supplement, copper oxide needles (CuOn) and copper oxide bolus. Feed intakes, mineral content of feed, dry matter and nutrient digestibilities, supplement disappearance from the rumen and copper (Cu) concentrations in the blood were monitored. Hay from Highland Valley Copper was high Cu (19.09 ppm), high Mo (49.68 ppm) feed. Severe cases of molybdenosis were expected but did not develop in cattle. Feeding harvested sun-cured high Mo forage lessens the hazard of molybdenosis. The Cu supplements had little or no effect on dry matter or nutrient digestibilities nor on rumen metabolism. Cu concentrations in the blood were increased. Research grazing fresh forage is required before making conclusive recommendations for using mine waste dumps and tailings ponds for forage production.Non UBCUnreviewedOthe

Effects of cpap therapy on blood pressure variability (BPV) in people with comorbid obstructive sleep apnoea (OSA) and cardiovascular disease (CVD): save trial

E. Van Ryswyk, W. Quan, R. Meng, Q. Li, C. Anderson, R. Woodman, K. Loffler, D. Zheng, R. D. McEvo