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  • Ritter Wilkins posted an update 1 day, 9 hours ago

    As a result, the related cumulative environmental and health effects can be more intensive. It can be emphasized that all countries located in the coastal areas of the Persian Gulf and the Gulf of Oman need to modify their solid waste management, plastic waste in particular, policies to conserve sensitive marine ecosystems.False killer whales are long-lived, slow to mature, apex predators, and therefore susceptible to bioaccumulation of persistent organic pollutants (POPs). Hawaiian waters are home to three distinct populations pelagic; Northwestern Hawaiian Islands (NWHI) insular; and main Hawaiian Islands (MHI) insular. Following a precipitous decline over recent decades, the MHI population was listed as “endangered” under the Endangered Species Act in 2012. This study assesses the risk of POP exposure to these populations by examining pollutant concentrations and ratios from blubber samples (n = 56) related to life history characteristics and MHI social clusters. Samples were analyzed for PCBs, DDTs, PBDEs, and some organochlorine pesticides. Skin samples (n = 52) were analyzed for stable isotopes δ13C and δ15N to gain insight into MHI false killer whale foraging ecology. Pollutant levels were similar among populations, although MHI whales had a significantly higher mean ratio of DDTs/PCBs than NWHI whales. The ∑PCB concentrations of 28 MHI individuals (68%) sampled were equal to or greater than suggested thresholds for deleterious health effects in marine mammals. The highest POP values among our samples were found in four stranded MHI animals. Eight of 24 MHI adult females have not been documented to have given birth; whether they have yet to reproduce, are reproductive senescent, or are experiencing reproductive dysfunction related to high POP exposure is unknown. Juvenile/sub-adults had significantly higher concentrations of certain contaminants than those measured in adults, and may be at greater risk of negative health effects during development. Multivariate analyses, POP ratios, and stable isotope ratios indicate varying risk of POP exposure, foraging locations and potentially prey items among MHI social clusters. Our findings provide invaluable insight into the ongoing risk POPs pose to the MHI population’s viability, as well as consideration of risk for the NWHI and pelagic stocks.Background Ambient air pollutants can increase cardiovascular mortality. One possible mechanism is the effect on the autonomic balance of the cardiovascular system. Studies on acute effects of particulate matter (PM) exposure on heart rate variability (HRV), a surrogate marker for autonomic balance, in patients with prior myocardial infarction (MI) revealed inconsistent results. Method We prospectively enrolled participants with acute MI. These participants received a 24-hour Holter electrocardiography examination and echocardiography six months after the index MI. Linear [standard deviation of all normal to normal intervals, standard deviation of NN intervals (SDNN), and a low-frequency to high-frequency ratio (LF/HF)] and non-linear parameters of heart rate variability [multiscale entropy (MSE)] were calculated to show autonomic balance. Data for PM2.5, PM2.5-10, and PM10, were obtained from a fixed-site station in Taiwan. Linear mixed effect models were used to estimate acute effects (within 0-3 days) of PM exposure (per 10 μg/m3) on heart rate variability. Results A total of 90 participants were enrolled in this study with a mean age of 58.7 (13.3) and 83 (92.2%) male participants. Traditional HRV parameters, SDNN and LF/HF, were positively correlated with two-day lagged PM2.5-10 and PM10 [adjusted beta coefficient SDNN 130.3 and 58.5; LH/HF 0.32 and 0.21 (all p less then or = 0.01)]. MSE slopes 1-5 were negatively correlated with same-day PM2.5-10 and PM10 (adjusted beta coefficient -0.011 (p = 0.01) and -0.005 (p = 0.02), respectively). The left ventricular ejection fraction was negatively correlated with one-day lagged PM2.5-10, and PM10 (adjusted beta coefficient -0.49 and -0.4, respectively; both p less then 0.05), after adjusting for MI size. Conclusion Our results suggest that coarse PM may acutely affect cardiac autonomic balance. MSE is a sensitive marker for detecting changes in autonomic imbalance in patients with prior MI following acute PM exposure.Bogs and fens cover 6 and 21%, respectively, of the 140,329 km2 Oil Sands Administrative Area in northern Alberta. Regional background atmospheric N deposition is low ( less then 2 kg N ha-1 yr-1), but oil sands development has led to increasing N deposition (as high as 17 kg N ha-1 yr-1). JIB-04 nmr To examine responses to N deposition, over five years, we experimentally applied N (as NH4NO3) to a poor fen near Mariana Lake, Alberta, unaffected by oil sands activities, at rates of 0, 5, 10, 15, 20, and 25 kg N ha-1 yr-1, plus controls (no water or N addition). At Mariana Lake Poor Fen (MLPF), increasing N addition 1) progressively inhibited N2-fixation; 2) had no effect on net primary production (NPP) of Sphagnum fuscum or S. angustifolium, while stimulating S. magellanicum NPP; 3) led to decreased abundance of S. fuscum and increased abundance of S. angustifolium, S. magellanicum, Andromeda polifolia, Vaccinium oxycoccos, and of vascular plants in general; 4) led to an increase in stem N concentrations in S. angustifolium and S. magellanicum, and an increase in leaf N concentrations in Chamaedaphne calyculata, Andromeda polifolia, and Vaccinium oxycoccos; 5) stimulated root biomass and production; 6) stimulated decomposition of cellulose, but not of Sphagnum or vascular plant litter; and 7) had no or minimal effects on net N mineralization in surface peat, NH4+-N, NO3–N or DON concentrations in surface porewater, or peat microbial composition. Increasing N addition led to a switch from new N inputs being taken up primarily by Sphagnum to being taken up primarily by shrubs. MLPF responses to increasing N addition did not exhibit threshold triggers, but rather began as soon as N additions increased. Considering all responses to N addition, we recommend a critical load for poor fens in Alberta of 3 kg N ha-1 yr-1.

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