56 (95% CI: 5 37-5 73) for risk variant carriers (CC+CT) and was

56 (95% CI: 5.37-5.73) for risk variant carriers (CC+CT) and was 5.48 (95% CI: 5.36-5.61) for noncarriers (TT) (p = 0.56). rs2118181 was not associated with TAA or TAAD. rs10519177 was not associated with TAD, TAA, or TAAD in the Yale study. Thus, the Yale study provided further support for the association of the FBN-1 rs2118181SNP with TAD.”
“Following intense overfishing in the 1970s, the western stock of Atlantic bluefin tuna (Thunnus thynnus) experienced

a long period of depressed abundance, which has been attributed to failure of the population to periodically produce large numbers of juveniles, the western stock mixing with the more highly exploited eastern stock (fisheries in the Northeast Atlantic Ocean and Mediterranean Sea), and regime shift in the population’s ecosystem resulting in lower replacement rates. To evaluate the presence this website of relatively strong years of juvenile production, we analyzed age structure from a recent sample of otoliths (ear stones) YH25448 chemical structure collected from the western stock (2011-2013, North Carolina, U.S.A., winter fishery). Mixing levels for the recent sample were analyzed using otolith stable isotopes to test whether age structure might be biased through immigration of eastern stock bluefin tuna. Age structure from historical samples collected from United States and Canadian fisheries (1975-1981) was

compared with more recent samples (1996-2007) to examine

whether demographic changes had occurred to the western stock that might have disrupted juvenile production. Relatively high juvenile production occurred in 2003, 2005, learn more and 2006. Otolith stable isotope analysis showed that these recruitments were mostly of western stock origin. However, these high recruitments were bigger than 2-fold less than historical recruitment. We found substantial age truncation in the sampled fisheries. Half the historical sample was bigger than 20 years old (mean age = 20.1 [SD 3.7]; skewness = -0.3), whereas smaller than 5% of the recent sample was bigger than 20 years old (mean age = 13.4 [SD 3.8]; skewness = 1.3). Loss of age structure is consistent with changes in fishing selectivity and trends in the stock assessment used for management. We propose that fishing, as a forcing variable, brought about a threshold shift in the western stock toward lower biomass and production, a shift that emulates the regime shift hypothesis. An abbreviated reproductive life span compromised resilience by reducing the period over which adults spawn and thereby curtailing the stock’s ability to sample year-to-year variability in conditions that favor offspring survival (i.e., storage effect). Because recruitment dynamics by the western stock exhibit threshold dynamics, returning it to a higher production state will entail greater reductions in exploitation rates.

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