News

New PhD student: Kathie Treen

Kathie Treen

I’m a first year PhD student supervised by Hywel Williams.  My topic is: “Online (mis)information and climate change: Using network analysis and machine learning to understand environmental debate”.  Whilst data science is central to this topic, the research will be interdiscplinary, incorporating relevant research in quantitative social sciences, communications science and environmental politics.

I have an MBA from Exeter and prior to that undertook a BSc Mathematics at Durham and an MSc in Operations Research at Lancaster.  In addition to my academic qualifications I have 15 years of industry experience working primarily in Reporting and Analyis / Operations in a range of organisations including QinetiQ, BAE Systems Detica, Amazon (Audible) and most recently Crowdcube.

My dissertation for my MBA was titled Measuring the Business Benefits of Social Initiatives and was undertaken with Sony Europe and won the Hutton Prize for Excellence at Exeter.

New PhD student: Sarah Menezes

Sarah Menezes

My name is Sarah Menezes and I am a first year PhD student in the Computer Science Department. My research is in the area of Data Science and my topic relates to the climate change debate on social media platforms. My supervisor is Dr. Hywel Williams.

Prior to joining the University of Exeter in 2018, I worked in Software Quality Assurance and Testing for 16 years. After completing my Bachelor’s in Computer Science at the Florida Institute of Technology in 2002, I worked at Texas Instruments for over 3 years and then at General Electric (GE Transportation in Melbourne, FL) for close to 13 years. As a Software QA Engineer and Software QA Manager, I lead the testing, releases and installations of train management systems for US railroads.

My expertise in the software lifecycle and in agile development took me to a different path for the first half of 2018. During that time I worked as an Agile Scrum Master for Satcom Direct. As part of a scrum team I worked closely with the members of the team (Developers, QA and Product Owner) to support and improve agile processes.

Summer school trip: Lake Como School of Complex Networks

Iraklis and I recently attended the Lake Como School of Advanced Studies summer school on Complex Networks: Theory, Methods and Applications.

The school featured a number of talks from prominent scholars in the field of complex networks. These sessions included both theoretical backgrounds and methodologies, as well as a number of experimental examples and real world applications of network science. During the Wednesday afternoon session, many students, including myself, presented on their recent work. This provided a really valuable opportunity to share new insights into the cutting-edge research taking place in universities across the world.

Beyond the academic benefit of a week’s study, we got to spend the week enjoying the weather of a Mediterranean spring whilst exploring the beautiful town of Como, situated in the foothills of the Alps.

Lake view.
The view from the lecture theatre at Lake Como.

Thanks to the speakers to the speakers for their interesting sessions, the other students for their excellent company and our funders for covering the costs. I really enjoyed my time at the school and look forward to putting some of the ideas I picked up to good use in the future.

New paper on Gaia and planetary habitability

New paper out – well done Arwen!

Arwen E Nicholson, David M Wilkinson, Hywel T P Williams, Timothy M Lenton; Gaian bottlenecks and planetary habitability maintained by evolving model biospheres: The ExoGaia model, Monthly Notices of the Royal Astronomical Society, , sty658, https://doi.org/10.1093/mnras/sty658

The search for habitable exoplanets inspires the question – how do habitable planets form? Planet habitability models traditionally focus on abiotic processes and neglect a biotic response to changing conditions on an inhabited planet. The Gaia hypothesis postulates that life influences the Earth’s feedback mechanisms to form a self-regulating system, and hence that life can maintain habitable conditions on its host planet. If life has a strong influence, it will have a role in determining a planet’s habitability over time. We present the ExoGaia model – a model of simple ‘planets’ host to evolving microbial biospheres. Microbes interact with their host planet via consumption and excretion of atmospheric chemicals. Model planets orbit a ‘star’ which provides incoming radiation, and atmospheric chemicals have either an albedo, or a heat-trapping property. Planetary temperatures can therefore be altered by microbes via their metabolisms. We seed multiple model planets with life while their atmospheres are still forming and find that the microbial biospheres are, under suitable conditions, generally able to prevent the host planets from reaching inhospitable temperatures, as would happen on a lifeless planet. We find that the underlying geochemistry plays a strong role in determining long-term habitability prospects of a planet. We find five distinct classes of model planets, including clear examples of ‘Gaian bottlenecks’ – a phenomenon whereby life either rapidly goes extinct leaving an inhospitable planet, or survives indefinitely maintaining planetary habitability. These results suggest that life might play a crucial role in determining the long-term habitability of planets.