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Interrelationships between surface water and groundwater dynamics ofalpha- and gamma-hexachlorocyclohexane (HCH) were investigated by determining their detection frequency and concentrations in surface water that originated primarily from surface runoff of snow and rain andin surface water that originated from ground water. In the prairie ecozone in Saskatchewan, where lindane (gamma-HCH) is currently used, lindane and alpha-HCH were detected in about 50% of water samples taken from lakes and ponds that are recharged primarily by surface runoff (N = 43 sites). Maximum concentrations for lindane and alpha-HCH were 0.011 and 0.004 5 g/L, respectively. Isomers of HCH were not detected in any of the eight prairie springs that were examined (N = 10 samples). These springs originate from ground water located beneath agricultural lands. In the montane ecozone of Alberta where lindane is not used for agricultural purposes, only alpha-HCH was detected frequently in the Waterton and Athabasca rivers. From 1976 to 1992, alpha-HCH was detected in 81% of water samples from the Waterton River with no significant difference in detection frequency through the year ((2for 12 months = 14.6, d.f. = 11, p = 0.20, N = 163 samples). The site on the Waterton River is located downstream from a series of large lakes with multiyear storage of surface water. In contrast, dischargefor the Athabasca River originates primarily from surface water during summer and ground water during winter. Detection frequency for alpha-HCH during these seasons was 53% and 2%, respectively, with the annual pattern a normal distribution. These results indicate that HCH isomers were not detected frequently in surface waters that originate from ground water. [ABSTRACT FROM AUTHOR]

In Canada, foreign-born older adults (FBOAs) have a higher prevalence of chronic conditions and poorer self-reported physical and mental health than their Canadian-born peers. However, very little research has explored FBOAs' experiences of health care after immigration. This review aims to understand the patient experiences of older immigrants within the Canadian health care system. Employing Arksey and O'Malley's framework for scoping reviews, we searched six databases and identified 12 articles that discussed the patient experience of this population. Although we sought to understand patient experience, the studies largely focused on barriers to care, including: communication difficulties, lack of cultural integration, systematic barriers in health care, financial barriers, and intersecting barriers related to culture and gender.This review provides insight into new areas of research and advocates for strengthened policy and/or programming. Our review also highlights that there is a paucity of literature for an ever-growing segment of the Canadian population.

Mucopolysaccharidosis type IIIC (MPSIIIC) is a severe, rare autosomal recessive disorder caused by variants in the heparan-α-glucosaminide N-acetyltransferase (HGSNAT) gene which result in lysosomal accumulation of heparan sulfate. We analyzed clinical presentation, molecular defects and their haplotype context in 78 (27 novel) MPSIIIC cases from 22 countries, the largest group studied so far. We describe for the first time disease-causing variants in the patients from Brazil, Algeria, Azerbaijan, and Iran, and extend their spectrum within Canada, Colombia, Turkey, and the USA. Six variants are novel: two missense, c.773A>T/p.N258I and c.1267G>T/p.G423W, a nonsense c.164T>A/p.L55*, a splice-site mutation c.494-1G>A/p.[P165_L187delinsQSCYVTQAGVRWHHLGSLQALPPGFTPFSYLSLLSSWNC,P165fs], a deletion c.1348delG/p.(D450fs) and an insertion c.1479dupA/p.(Leu494fs). The missense HGSNAT variants lacked lysosomal targeting, enzymatic activity, and likely the correct folding. The haplotype analysis identified founder mutations, p.N258I, c.525dupT, and p.L55* in the Brazilian state of Paraiba, c.493+1G>A in Eastern Canada/Quebec, p.A489E in the USA, p.R384* in Poland, p.R344C and p.S518F in the Netherlands and suggested that variants c.525dupT, c.372-2G>A, and c.234+1G>A present in cis with c.564-98T>C and c.710C>A rare single-nucleotide polymorphisms, have been introduced by Portuguese settlers in Brazil. Altogether, our results provide insights into the origin, migration roots and founder effects of HGSNAT disease-causing variants, and reveal the evolutionary history of MPSIIIC., (© 2019 Wiley Periodicals, Inc.)

Livestock slurry storages are sources of methane (CH₄), nitrous oxide (NO₂), and ammonia (NH₃) emissions. Total solids (TS) content is an indicator of substrate availability for CH₄ and N₂O production and NH₃ emissions and is related to crust formation, which can affect these gas emissions. The effect of TS on these emissions from pilot-scale slurry storages was quantified from 20 May through 16 Nov. 2010 in Nova Scotia, Canada. Emissions from six dairy slurries with TS ranging from 0.3 to 9.5% were continuously measured using flow-through steady-state chambers. Methane emissions modeled using the USEPA methodology were compared with measured data focusing on emissions when empty storages were filled, and retention times were >30 d with undegraded volatile solids (VS) remaining in the system considered available for CH₄ production (VS carry-over). Surface crusts formed on all the slurries. Only the slurries with TS of 3.2 and 5.8% were covered completely for ∼3 mo. Nitrous oxide contributed <5% of total greenhouse gas emissions for all TS levels. Ammonia and CH₄ emissions increased linearly with TS despite variable crusting, suggesting substrate availability for gas production was more important than crust formation in regulating emissions over long-term storage. Modeled CH₄ emissions were substantially higher than measured data in the first month, and accounting for this could improve overall model performance. Carried-over VS were a CH₄ source in months 2 through 6. The results of this study suggest that substrate availability regulates emissions over long-term storage and that modifying the USEPA model to better describe carbon cycling is warranted., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Background and Aim of the Study: The hemodynamic performance of stentless aortic bioprostheses has been previously well described. Because the potential for prosthesis-patient mismatch is greatest for small valves in the aortic position, the present study sought to compare the hemodynamic performance and degree of left ventricular (LV) mass regression between valve sizes for the Toronto SPV valve, with special interest in measures of relief of LV outflow obstruction afforded by the smallest valves., Methods: This study included 257 patients (178 men, 79 women; mean age 63.5+/-11.4 years; range: 34-93 years) from six investigative centers with complete echocardiography/Doppler data obtained through three years. Valve sizes implanted were 21 mm (n = 11), 23 mm (n = 23), 25 mm (n = 58), 27 mm (n = 83), and 29 mm (n = 82). Echocardiography was performed at discharge, six months, one year, and yearly thereafter, and interpreted in a centralized core laboratory. Mean gradient, effective orifice area (EOA), indexed EOA, and absolute and percent change in LV mass index were used as markers of hemodynamic performance., Results: For all valve sizes, mean and peak gradients fell and EOA increased early after surgery. There were no differences between groups in the degree to which gradients fell, and EOA increased from discharge to one year follow up. At one year, indexed EOA was 0.9 cm2/m2 for valve sizes 21 and 23 mm, and 1.0-1.2 cm2/m2 for sizes 25, 27 and 29 mm. There was statistically significant LV mass regression for all valve sizes (p <0.05), and no differences between valve sizes in the magnitude of absolute or percent change in LV mass index between baseline and three years., Conclusion: The Toronto SPV valve demonstrates excellent parameters of hemodynamic performance for all valve sizes, including the smallest valves used in only a minority of patients. Findings of indexed EOA > or = 0.9 cm2/m2, and equivalent degrees of LV mass regression for all valve sizes, reinforces the excellent hemodynamic performance of stentless aortic bioprostheses, and suggests that prosthesis-patient mismatch should be minimized with these valves.

Objective: The authors estimated the prevalence of psychoses among the Hutterites in Manitoba, Canada, who lived in 102 communal farms or colonies. The study stemmed from an earlier epidemiological survey of North American Hutterite colonies (1950-1953), in which a low prevalence of psychoses was documented., Method: Psychiatrically ill individuals identified during the previous survey were rediagnosed with DSM-IV criteria. A current provincial health insurance claims database was queried anonymously for the period June 1992-May 1997, and the prevalence rate of disease among Hutterites, identified by distinctive surnames and unique postal addresses, was compared with the rate in the entire population of the province of Manitoba and in a comparison group of persons with Hutterite surnames but with addresses outside the Hutterite colonies., Results: The annual prevalence of schizophrenia among the communal Hutterites, estimated from the database search by using ICD-9 criteria, was consistent with the prevalence found in the prior epidemiological survey (annual mean of 1.2/1,000 population, compared with 1.3/1,000 in the prior survey). The database search yielded a significantly lower prevalence for schizophrenia and other functional psychoses among communal Hutterites as well as among the comparison group, compared to the total Manitoba population. There was also lower prevalence for affective psychoses and adjustment reaction disorders among the communal Hutterites, compared to the total Manitoba population. Rates for neurotic disorders were elevated both among the communal Hutterites and the comparison group., Conclusions: The prevalence of specific psychoses was reduced among the Hutterites, although neurotic disorders were more prevalent. These findings suggest some specificity, although possible artifacts such as ascertainment bias must be considered. Further research is needed to examine genetic and environmental factors that may contribute to reduced prevalence of specific psychoses among the Hutterites.