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Sircar, R.

Publications and source records attributed to Sircar, R..

2 recordsLinked to original sources

Doctoral Students as Carbon Accountants: Calculating Carbon Costs of a PhD in Neuroscience

Research is an energy and resource-demanding activity. However, despite increasing awareness and emerging sustainability initiatives, a paucity of data and methodological inconsistency continue to hamper effective and accountable emissions mitigation. With > 250,000 doctoral students graduating annually across all academic disciplines, empowering PhD students to engage in carbon accounting could provide a sizable and robust source of carbon data alongside a powerful generational force for decarbonisation. Here, we demonstrate how doctoral students and other researchers can consistently measure the carbon footprint of their work, using one PhD students research in a neuroscience Drosophila lab as our case study. We present a comprehensive life-cycle assessment of the equivalent carbon dioxide emissions (CO2e) generated by the students research activities, including measurement of scope 1 emissions associated with Drosophila husbandry; calculation of time- and region-specific scope 2 emissions produced by widely used techniques including calcium imaging, electrophysiology, and optogenetics; and estimation of scope 3 emissions associated with procurement and research-related travel. We found that research-related travel and procurement of laboratory supplies were responsible for the majority of annual emissions, up to 1942 kg CO2e and 543 kg CO2e respectively after accounting for aircraft radiative forcing. Using NESOs open-source Carbon Intensity API to account for temporal and geographical variation in the carbon intensity of UK National Grid energy, we found that persistent laboratory energy consumption released 10.99 kg CO2e, with an additional 3.56 kg CO2e scope 2 and 3.6 kg CO2e scope 1 emissions underpinning direct research activities. Finally, we discuss the challenges of accurately carbon foot printing research across disciplines in the UK and beyond, highlighting the value of regionally precise open-source energy mix data and the need for data openness within research supply chains. Overall, we present a common framework for including carbon footprint analyses as Carbon Appendices to PhD theses to generate carbon footprint data across disciplines. Beyond the benefits of such data for informed emissions mitigation, we envision doctoral students carrying insights from carbon appendices forward into academia and industry to catalyse a community-driven decarbonisation of the research sector.

neuroscience↗

Bile Acid Biosynthesis Avoiding Cholesterol

Bile acids are the end products of cholesterol metabolism secreted into bile. They are essential for the absorption of lipids and lipid soluble compounds from the intestine. Here we have investigated the bile acid content of plasma and urine from patients with a defect in cholesterol biosynthesis, i.e. Smith-Lemli-Opitz syndrome (SLOS), resulting in elevated levels of 7-dehydrocholesterol (7-DHC), an immediate precursor of cholesterol. Using liquid chromatography - mass spectrometry (LC-MS) we have identified a novel pathway of bile acid biosynthesis in SLOS avoiding cholesterol starting with 7-DHC. This pathway also proceeds to a minor extent in healthy individuals. Monitoring of the pathway products could provide a rapid diagnostic for SLOS while elevated levels of pathway intermediates could be responsible for some of the features of the disease. Importantly, intermediates in the pathway are modulators of the activity of Smoothened, an oncoprotein that mediates Hedgehog signalling during embryogenesis and regeneration of postembryonic tissue.

biochemistry↗