The history of the Earth system is a story of change. Some changes are gradual and benign, but others, especially those associated with catastrophic mass extinction, are relatively abrupt and destructive. What sets one group apart from the other? Here, I hypothesize that perturbations of Earth’s carbon cycle lead to mass extinction if they exceed either a critical rate at long time scales or a critical size at short time scales. By analyzing 31 carbon isotopic events during the past 542 million years, I identify the critical rate with a limit imposed by mass conservation.

Chronic electronic (e) cigarette users have increased resting cardiac sympathetic nerve activity and increased susceptibility to oxidative stress. The purpose of the present study is to determine the role of nicotine versus non-nicotine constituents in e-cigarette emissions in causing these pathologies in otherwise healthy humans.

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Climate change is likely to profoundly modulate the burden of infectious diseases. However, attributing health impacts to a changing climate requires being able to associate changes in infectious disease incidence with the potentially complex influences of climate. This aim is further complicated by nonlinear feedbacks inherent in the dynamics of many infections, driven by the processes of immunity and transmission.

Physical forcing of cyclonic phenomenon on water quality often exerts stress on marine and estuarine ecosystems due to their unpredictability. The post-cyclonic changes in phytoplankton biomass have been reported in the Bay of Bengal. In addition, cyclones also intensify physical processes resulting in entrainment of nutrient-rich water from deeper depths into surface leading to regional phytoplankton blooms.

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Tool use has allowed humans to become one of the most successful species. However, tool-assisted foraging has also pushed many of our prey species to extinction or endangerment, a technology-driven process thought to be uniquely human. Here, we demonstrate that tool-assisted foraging on shellfish by long-tailed macaques (Macaca fascicularis) in Khao Sam Roi Yot National Park, Thailand, reduces prey size and prey abundance, with more pronounced effects where the macaque population size is larger.

This study explores the uncertainty introduced in global assessments of coastal flood exposure and risk by not accounting for water level attenuation due to land–surface characteristics. We implement a range of plausible water level attenuation values in the flood module of the Dynamic Interactive Vulnerability Assessment (DIVA) modelling framework and assess the sensitivity of flood exposure and flood risk indicators to differences in attenuation rates. Results show a reduction of up to 47 % in area exposure and even larger reductions in population exposure and expected flood damages.

Climate change is a well-documented driver of both wildlife extinction and disease emergence, but the negative impacts of climate change on parasite diversity are undocumented. We compiled the most comprehensive spatially explicit data set available for parasites, projected range shifts in a changing climate, and estimated extinction rates for eight major parasite clades.

Having successfully negotiated the international space for India to address and overcome technological and systemic gaps so that it can then build the required ecosystem for phasing out HFCs, the Government of

Natural environments, including green spaces, may have beneficial impacts on brain development. However, longitudinal evidence of an association between long-term exposure to green spaces and cognitive development (including attention) in children is limited. The researchers evaluated the association between lifelong residential exposure to green space and attention during preschool and early primary school years.

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This article discusses a novel way of purifying biodiesel without using water in the biodiesel purification process.In this work, waterless purification of biodiesel has been investigated using cow dung ash as an adsorbent.

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