Targeted environmental monitoring reveals contamination by known chemicals, but may exclude potentially pervasive but unknown compounds. Marine mammals are sentinels of persistent and bioaccumulative contaminants due to their longevity and high trophic position. Using nontargeted analysis, we constructed a mass spectral library of 327 persistent and bioaccumulative compounds identified in blubb...

Previous climate model projections of climate change accounted for external forcing from natural and anthropogenic sources but did not attempt to predict internally generated natural variability. We present a new modeling system that predicts both internal variability and externally forced changes and hence forecasts surface temperature with substantially improved skill throughout a decade, bot...

Background and objectives: Tyrosinase is a copper containing oxidase which is crucial for controlling the production of melanin in creatures such as bacteria, fungi, plants and mammals. It is involved in the first two steps of melanin biosynthesis and leads to pigmentation and different types of cancer such as melanoma. Also, it is responsible for browning of fruits and vegetab...

Trace metals are intrinsic, natural constituents of our environment. Apart from the natural sources, several anthropogenic ones also contribute to metal concentrations in the environment. Some of the anthropogenic sources of the metals in the environment are: mining, smelting, production and use of the compounds and materials containing the metals, burning of fossil fuels, waste dumping and lea...

Elevated levels of mercury in aquatic environments remote from industrial sources have been broadly attributed to longrange atmospheric transport and deposition of anthropogenic Hg. Evidence in support of this prevailing scientific viewsglobal biogeochemical Hg models, sedimentary archives of historic Hg fluxes, and geographic trends in soil Hgshave been challenged as being insufficiently rigor...

the total concentration and percentage of heavy metals content in the sediment of hashilan wetland, kermanshah province, was assessed in summer 2015. the total concentrations of cu, pb, and fe were around 18.57, 6.95 and 379.24 μg g-1, respectively. successive extractions of the samples showed a decreasing trend as follows: residual>organic matter>iron and manganese oxides>exchangeable parts. t...

Soundscapes pose both evolutionarily recent and long-standing sources of selection on acoustic communication. We currently know more about the impact of evolutionarily recent human-generated noise on communication than we do about how natural sounds such as pounding surf have shaped communication signals over evolutionary time. Based on signal detection theory, we hypothesized that acoustic phe...

[1] This study presents a new hypothesis to explain the observed variation of CH4 and dC-CH4 over the last millennium. It was originally proposed that the observed minimum of dC-CH4 prior to the start of industrialization is caused by a large shift in biomass burning emissions between 1400 and 1700 A.D. According to our new hypothesis, however, the dC-CH4 minimum is the first sign of the global...