Methane emissions from abandoned coal and oil and gas developments in New Brunswick and Nova Scotia

Energy reserves have been exploited in the Atlantic Canadian provinces since the early 1600s, and many fossil fuel extraction sites have been abandoned over this long history of energy development. Oil, natural gas, and coal extraction sites are a source of greenhouse gas emissions, particularly for methane (CH₄). In this study, we used multiple sampling methods to measure CH₄ from abandoned coal mine openings in Nova Scotia and a legacy oilfield in New Brunswick. Atmospheric and shallow soil gases were sampled around legacy sites using flux rate chamber measurements (spatial and temporal) and plot-scale atmospheric gas surveys, in addition to regional gas screening surveys over larger populations of sites to confirm whether small-scale observations were reflected regionally. Only one oil and gas site (2.4 ± 3.1⋅ 10² mg m^- 2 day^- 1) and one abandoned coal mine opening (1.0 ± 1.1⋅ 10² mg m^- 2 day^- 1) were affected by soil CH₄ migration, though rates of leakage were minimal and would rank as low severity on industrial scales. Plot-scale atmospheric gas screening showed super-ambient CH₄ concentrations at 5 sites in total (n = 16), 2 coal adits and 3 abandoned oil and gas wells. Regional gas screening surveys suggest that 11% of legacy oil and gas sites have some emission impacts, compared with 1-2% of legacy coal sites. These frequencies are close, albeit lower than the 15% of legacy oil and gas sites and 10% of abandoned coal mine openings flagged from our aggregated small-scale observations. These sites may emit less than other developments studied to date either because more time has elapsed since extraction, or because differences in regional geology reduce the likelihood of sustained emissions. This study provides valuable information to help understand the methane emission risks associated with legacy energy sites.

Embryo transfer under ultrasound guidance improves pregnancy rates after in-vitro fertilization

Between October 1998 and January 1999, we examined the influence of ultrasound guidance in embryo transfer on pregnancy rate in 362 patients from our in-vitro fertilization (IVF)-embryo transfer programme. These patients were prospectively randomized into two groups: 182 had ultrasound-guided embryo replacement, and 180 had clinical touch embryo transfer. There were no statistically significant differences between the two groups with respect to age, cause of infertility and in the characteristics of the IVF cycle. The pregnancy rate was significantly higher among the ultrasound-guided embryo transfer group (50%) compared with the clinical touch group (33.7%) (P < 0.002). Furthermore, there was also a significant increase in the implantation rate: 25.3% in the ultrasound group compared with 18.1% in the clinical touch group (P < 0.05). In conclusion, ultrasound assistance in embryo transfer significantly improved pregnancy and implantation rates in IVF.

Conservation genetics of an endangered Catalonian cattle breed ("Alberes")

We biochemically analyzed and characterized the genetic structure of a population in danger of extinction ,"Alberes", a local cattle breed of the Catalonian Pyrenees (Spain and France). Ninety-two individuals were analyzed for five polymorphic genetic loci (Hb, Alb, Tf, Gc and Ptf2). The animals were grouped according to coat color: Fagina Alberes variety (N = 39) and Black Alberes variety (N = 53). The genetic structures and relationships between these subpopulations and one "outgroup" breed ("Bruna dels Pirineus") were analyzed and compared by using F-statistics. We determined that inbreeding in the Alberes breed is not significant, since negative and nonsignificant FIT and FIS values were obtained. The average genetic differentiation between subpopulations within the Alberes breed was 1.5% (FST = 0.015; P < 0.05), with an effective number of 4.1 individuals exchanged between subpopulations per generation (gene flow). The results obtained in this study corroborate the potential danger of extinction of the breed. The Black Alberes variety is proposed as the principal nucleus of genetic conservation for this breed, as it seems to show a higher degree of genetic isolation from other foreign populations.