Publications by authors named "D J Penman"

Rock metamorphism releases substantial CO over geologic timescales (>1 My), potentially driving long-term planetary climate trends. The nature of carbonate sediments and crustal thermal regimes exert a strong control on the efficiency of metamorphic CO release; thus, it is likely that metamorphic CO degassing has not been constant throughout time. The Proterozoic Earth was characterized by a high proportion of dolomite-bearing mixed carbonate-silicate rocks and hotter crustal regimes, both of which would be expected to enhance metamorphic decarbonation.

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Article Synopsis
  • The late Paleocene and early Eocene periods were marked by long-term global warming and short, abrupt warming events called hyperthermals, largely influenced by greenhouse gases but possibly affected by other factors like tectonics.
  • Researchers analyzed data from planktic foraminifera to reconstruct sea surface temperatures and CO levels, focusing on key events such as the Paleocene-Eocene Thermal Maximum (PETM) and Eocene Thermal Maximum 2 (ETM-2).
  • Findings indicate a strong connection between CO and temperature, with different carbon sources contributing to the CO increases during these periods, and the emissions from these events are comparable to future projections, highlighting their relevance to current climate change discussions.
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Multiple abrupt warming events ("hyperthermals") punctuated the Early Eocene and were associated with deep-sea temperature increases of 2 to 4 °C, seafloor carbonate dissolution, and negative carbon isotope (δC) excursions. Whether hyperthermals were associated with changes in the global ocean overturning circulation is important for understanding their driving mechanisms and feedbacks and for gaining insight into the circulation's sensitivity to climatic warming. Here, we present high-resolution benthic foraminiferal stable isotope records (δC and δO) throughout the Early Eocene Climate Optimum (~53.

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Aim: A treatment strategy for patients with a significant polyp or early colon cancer (SPECC) of the rectum presents a challenge due to the significant rate of covert malignancy and lack of standardized assessment. For this reason, NICE recommends multidisciplinary meetings to improve outcomes. The primary aim of the present study was to report the performance of our specialist early rectal cancer (SERC) multidisciplinary team (MDT) in correctly substratifying the risk of cancer and to discuss the limitations of staging investigations in those patients with "poor outcomes".

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Background: Gastrointestinal (GI) endoscopy is one of healthcare's main contributors to climate change. We aimed to assess healthcare professionals' attitudes and the perceived barriers to implementation of sustainable GI endoscopy.

Methods: The LEAFGREEN web-based survey was a cross-sectional study conducted by the European Society of Gastrointestinal Endoscopy (ESGE) Green Endoscopy Working Group.

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