Devang Haresh Liya

Obscuration geometry around AGN

Active Galactic Nucleus (AGN) is a highly luminous compact region at the center of a galaxy. Despite the first AGNs being discovered over 100 years ago, our understanding, till today, of AGN activity and the processes regulating it remains severely incomplete. Detailed studies of the individual sources are extremely useful, providing a magnifying glass to study the circum-nuclear environment around the central supermassive black hole that drives the emission from the AGNs. This project is multi-mission broadband study of x-ray spectrum of one such heavily obscured AGN using robust global sampling algorithms in Bayesian X-ray Analysis (BXA) package. Dr. Aru Beri and Dr. Peter Boorman are supervising this project.

Constrainting galaxy evolution and cosmology using novel clustering statistics

Voronoi tessellations based Voronoi Volume Function (VVF) is a novel unexplored probe for cosmology and galaxy evolution. We (Dr. Shadab Alam, Dr. Aseem Paranjape, and I) use VVF as a clustering statistic and simulated galaxy redshift catalogues to study the power of VVF in constraining parameters governing galaxy formation in dark matter halos as well as the cosmological parameters simultaneously.

Mass Function of Collapsed Halos and the Excursion Set

Observed mass distribution of the dark matter halos in the universe — known as halo mass function — shows significant departures from theoretical predictions. Modelling the halo collapse as a stochastic problem could help us explain the observed departures. This approach is called excursion set approach. In my master's thesis, I reviewed the properties of the dark matter halos, methods to study them, and methods to predict the form of the halo mass function. I also developed a set of programs for simulating the excursion set formalism with arbitrary absorbing barrier and an arbitrary matter power spectrum. Prof. Jasjeet Singh Bagla was my supervisors for this project.

Looking at the radio sky

The sky looks drastically different in different wavelenths of light. Each wavelength requires specialized telescopes and training in using those telescopes. Sky Watch Array Network (SWAN) is a MWA type radio telescope. We used this setup to observe the Sun, developed a pipeline to process the raw data generated from the telescope, performed interferometary and finally produced an image of the Sun at 195 MHz. Snippets of code used in the pipeline can be found in this repository. Feel free to contact me if you need additional resources or have suggestions on improving the pipeline.

Identifying drug targets in SARS-CoV-2

COVID-19 pandemic that made the Zoom an integral part of our lives, was caused by a virus named SARS-CoV-2. We developed CRAM — a tiny piece of code to identify the non-mutating stable sites in the SARS-CoV-2 genome. We then used these sites for drug targeting and studied the interaction between the selected drugs and the protein produced by the stable sites using molecular dynamics simulations. This work was done in collabortation with Ashwin Kumar Jainarayanan of University of Oxford, and Dr. Arpit Kumar Pradhan of Ludwig Maximilian University of Munich. The results are peer reviewed and published in PLOS One.

FearoMone

Nearly 40% of India's foodgrain production is lost during the post-harvest phase. Rats and mice are one of the major causes of this loss. Inspired by the natural prey-predator relationship between rats and cats, we developed a bio-synthetic deterrent by using genetically engineered yeast to produce cat pheromones. We also developed variety of hardwares and softwares to safely deploy the product. We presented this work at the Giant Jamboree held in Boston, USA and were awarded a bronze medal along with a nomination for the best food and nutrition project. Visit the project website to learn more!

Other projects

QPromoters: Your go-to tool for predicting the strength of Saccharomyces cerevisiae promoters! Visit here for the online tool, here for the code repository, and here for accompanying article.

I am also intrigued by the concept of "RNA velocity" which is elegantly explained here by Sten Linnarsson. In this, one tries to reconstruct cell dynamics from single-cell RNA-sequencing data using a likelihood-based dynamical model. We are using tools such as scVelo, velocyto, and Seurat to apply this concept and study the dyanmics in Glioblastoma and COVID-19.

I am interested in using statistical techniques to solve real world problems. Please contact me if you have any new exciting ideas and can use my expertise!

Published articles

Liya, D. H., Anand, N. M., Jainarayanan, A. K., Elanchezhian, M., Seetharaman, M., Balakannan, D., & Pradhan, A. K. (2022). Drug repurposing and sequence analysis in S-glycoprotein variants reveals critical signature patterns and destabilization of receptor-binding domain in omicron variant. Journal of Biomolecular Structure and Dynamics, 1-18. doi:10.1080/07391102.2022.2127902

Anand N.M., Liya D.H., Pradhan A.K., Tayal N., Bansal A., et al. (2021) A comprehensive SARS-CoV-2 genomic analysis identifies potential targets for drug repurposing. PLOS ONE 16(3): e0248553. doi:10.1371/journal.pone.0248553

Liya, D. H., Elanchezhian, M., Pahari, M., Mouroug Anand, N., Suresh, S., Balaji, N., & Kumar Jainarayanan, A. (2023). QPromoters: sequence based prediction of promoter strength in Saccharomyces cerevisiae. All Life, 16(1). doi:10.1080/26895293.2023.2168304

Beal, J., Farny, N.G., Haddock-Angelli, T. ,Selvarajah, V. , Baldwin, G. S., Buckley-Taylor, R., Gershater M., Kiga, D., Marken, J., Sanchania, V., Sison A., Workman C. T. & iGEM Interlab Study Contributors et al. (2020) Robust estimation of bacterial cell count from optical density. Commun Biol 3, 512. doi:10.1038/s42003-020-01127-5

In preparation

Liya, D.H., Alam, S., Paranjape, A.: Impact of Galaxy physics on precision Cosmology from non-linear scales.

Liya, D.H., Boorman, P., Beri, A.: TBD

I strongly believe that everyone must get the opportunity to experience the excitement of doing science irrespective of their background. Therefore, I have always been actively involved in science communication and outreach activities. Following are some highlights from those activities.

I regularly volunteer for outreach activities at the Great North Museum: Hancock. These activities range from communicating my research to adults, to astronomy workshops for visually impaired kids.

One of many volunteers (and the webmaster) that helped in putting together Space Investigators, a 6-months long exhibition in the Great North Museum: Hancock. The exhibition is a multi-sensory journey through the history of astronomy and the present day research in the North East region of England.

Quizmaster at Vigyan Samagam — first mega science exhibition in India — Delhi edition.

Volunteered for Physics demonstrations for school children on IISER-Mohali foundation day celebration. Also designed and maintained the website for the event.

Was the convener of The Astronomy Club at IISER-Mohali from 2018 to 2021. During this time, I organized lectures, weekend astronomy hangouts, sky-watching sessions, quizzes, and other activities for undergraduate and graduate students of the institute.

Planned and organized an astronomy week at IISER-Mohali. This included demonstrations, games, myth-buster events, and hands-on sessions for variety of demographics like school children, undergraduates, graduates from other fields, members of the public, etc.

Trained new members of the SWAN group at IISER-Mohali in radio astronomy.

I also write a blog as a resource for anyone to get their hands dirty by analyzing real astronomical data.

Hosted a reddit AMA to spread awareness about synthetic biology and general scientific thinking in India as part of outreach for our iGEM 2018 project.