Sonia Grego

Education

• M.S. Università di Pisa (Italy), 1995
• Ph.D. University of Copenhagen (Denmark), 1999

Positions

• Associate Research Professor in the Department of Electrical and Computer Engineering

Publications

• Grego S, Cottingham R, Koottatep T, Panuvatvanich A, Mercer S, Hennessy S. Engineering field testing of non-sewered sanitation systems: Compendium of lessons learned. 2025.
• Zhou J, Luo Y, Darcy JW, Lafata KJ, Ruiz JR, Grego S. Long-term, automated stool monitoring using a novel smart toilet: A feasibility study. Neurogastroenterol Motil. 2025 Jan;37(1):e14954.
• Morrison L, Milliken C, Shurgot M, Grego S, Rajamanickam S, Ramalingam S. Womenu2019s toilet use behaviors and water use in a urine diversion squat pan toilet pilot. Journal of Water Sanitation and Hygiene for Development. 2024 Sep 1;14(9):886u201394.
• Rosario P, Seenivasan T, Viswash R, Ramalingam S, Barani V, Welling CM, et al. Impact of heat-treatment on wastewater analytical parameters. Water science and technologyu202f: a journal of the International Association on Water Pollution Research. 2023 Dec;88(11):2931u20139.
• Subramani P, Basil M, Rosario P, Jalaja DR, Choudhary V, Renganathan J, et al. Water recycling public toilets based on onsite electrochemical wastewater treatment. Environmental Science Water Research and Technology. 2023 Nov 13;10(1):157u201367.
• Grego S. The humble toilet is an opportunity for sustainable water reuse. Nature Water. 2023 Nov 1;1(11):900u20131.
• Zhou J, McNabb J, Decapite N, Ruiz JR, Fisher DA, Grego S, et al. Stool Image Analysis for Digital Health Monitoring By Smart Toilets. IEEE Internet of Things Journal. 2023 Mar 1;10(5):3720u201334.
• Kachoria P, Sasidaran S, Welling CM, Rosario P, Zhou J, Chakrabarty K, et al. Sensor-based evaluation of a Urine Trap toilet in a shared bathroom. The Science of the total environment. 2023 Jan;857(Pt 1):159178.
• Welling CM, Singleton DR, Haase SB, Browning CH, Stoner BR, Gunsch CK, et al. Predictive values of time-dense SARS-CoV-2 wastewater analysis in university campus buildings. The Science of the total environment. 2022 Aug;835:155401.
• Grego S, Welling CM, Miller GH, Coggan PF, Sellgren KL, Hawkins BT, et al. A hands-free stool sampling system for monitoring intestinal health and disease. Sci Rep. 2022 Jun 27;12(1):10859.
• Sasidaran S, Kachoria P, Raj A, Ramalingam S, Stoner BR, Sellgren KL, et al. Physical properties of menstrual hygiene waste as feedstock for onsite disposal technologies. Journal of Water Sanitation and Hygiene for Development. 2021 May 1;11(3):474u201382.
• Zhou J, DeCapite N, McNabb J, Ruiz JR, Fisher DA, Grego S, et al. Stool Image Analysis for Precision Health Monitoring by Smart Toilets. In: Proceedings of Machine Learning Research. 2021. p. 709u201329.
• Rosario P, Viswash R, Seenivasan T, Ramalingam S, Sellgren KL, Grego S, et al. Potential Pitfalls in Wastewater Phosphorus Analysis and How to Avoid Them. Environmental health insights. 2021 Jan;15:11786302211019218.
• Varigala S, Krishnaswamy S, Lohia CP, Hegarty-Craver M, Grego S, Luettgen M, et al. Optimal design of an electrochemical reactor for blackwater treatment. Water environment researchu202f: a research publication of the Water Environment Federation. 2021 Jan;93(1):148u201358.
• Russell KN, Preble EA, Hegarty-Craver M, Arrieux JP, Cole WR, Choi YS, et al. Feasibility of Mild Traumatic Brain Injury Assessment Based on Cardiovascular Response to Postural Change. The Journal of head trauma rehabilitation. 2020 Sep;35(5):E422u20138.
• Welling CM, Varigala S, Krishnaswamy S, Raj A, Lynch B, Piascik JR, et al. Resolving the relative contributions of cistern and pour flushing to toilet water usage: Measurements from urban test sites in India. The Science of the total environment. 2020 Aug;730:138957.
• Zhou J, Welling CM, Vasquez MM, Grego S, Chakrabarty K. Sensor-Array Optimization Based on Time-Series Data Analytics for Sanitation-Related Malodor Detection. IEEE transactions on biomedical circuits and systems. 2020 Aug;14(4):705u201314.
• Kawadiya S, Welling C, Grego S, Deshusses MA. Fecal Malodor Detection Using Low-Cost Electrochemical Sensors. Sensors (Basel, Switzerland). 2020 May;20(10):E2888.
• Varigala SK, Hegarty-Craver M, Krishnaswamy S, Madhavan P, Basil M, Rosario P, et al. Field testing of an onsite sanitation system on apartment building blackwater using biological treatment and electrochemical disinfection. Environmental Science Water Research and Technology. 2020 May 1;6(5):1400u201311.
• Welling CM, Sasidaran S, Kachoria P, Hennessy S, Lynch BJ, Teleski S, et al. Field testing of a household-scale onsite blackwater treatment system in Coimbatore, India. The Science of the total environment. 2020 Apr;713:136706.
• Sahondo T, Hennessy S, Sindall RC, Chaudhari H, Teleski S, Lynch BJ, et al. Field testing of a household-scale onsite blackwater treatment system in South Africa. The Science of the total environment. 2020 Feb;703:135469.
• Grego S, Barani V, Hegarty-Craver M, Rosario P, Madhavan P, Perumal P, et al. Characterization of fecal sludge as biomass feedstock for thermal treatment in the southern Indian state of Tamil Nadu. Gates Open Research. 2020 Jan 1;2.
• Zhou J, Welling CM, Kawadiya S, Deshusses MA, Grego S, Chakrabarty K. Sensor-Array optimization based on mutual information for sanitation-related malodor alerts. In: Biocas 2019 Biomedical Circuits and Systems Conference Proceedings. 2019.
• Heathers JAJ, Gilchrist KH, Hegarty-Craver M, Grego S, Goodwin MS. An analysis of stereotypical motor movements and cardiovascular coupling in individuals on the autism spectrum. Biological psychology. 2019 Mar;142:90u20139.
• Gilchrist KH, Hegarty-Craver M, Christian RB, Grego S, Kies AC, Wheeler AC. Automated Detection of Repetitive Motor Behaviors as an Outcome Measurement in Intellectual and Developmental Disabilities. Journal of autism and developmental disorders. 2018 May;48(5):1458u201366.
• Amsden JJ, Herr PJ, Landry DMW, Kim W, Vyas R, Parker CB, et al. Proof of Concept Coded Aperture Miniature Mass Spectrometer Using a Cycloidal Sector Mass Analyzer, a Carbon Nanotube (CNT) Field Emission Electron Ionization Source, and an Array Detector. Journal of the American Society for Mass Spectrometry. 2018 Feb;29(2):360u201372.
• Grego S, Barani V, Hegarty-Craver M, Raj A, Perumal P, Berg AB, et al. Soil-transmitted helminth eggs assessment in wastewater in an urban area in India. Journal of water and health. 2018 Feb;16(1):34u201343.
• Radauscher EJ, Parker CB, Gilchrist KH, Di Dona S, Russell ZE, Hall SD, et al. A miniature electron ionization source fabricated using microelectromechanical systems (MEMS) with integrated carbon nanotube (CNT) field emission cathodes and low-temperature co-fired ceramics (LTCC). International Journal of Mass Spectrometry. 2017 Nov 1;422:162u20139.
• Behrsing H, Hill E, Raabe H, Tice R, Fitzpatrick S, Devlin R, et al. In vitro exposure systems and dosimetry assessment tools for inhaled tobacco products: Workshop proceedings, conclusions and paths forward for in vitro model use. Alternatives to laboratory animalsu202f: ATLA. 2017 Jul;45(3):117u201358.
• Grego S, Dougherty ER, Alexander FJ, Auerbach SS, Berridge BR, Bittner ML, et al. Systems biology for organotypic cell cultures. In: ALTEX. 2017. p. 301u201310.
• Sellgren KL, Hawkins BT, Grego S. An optically transparent membrane supports shear stress studies in a three-dimensional microfluidic neurovascular unit model. Biomicrofluidics. 2015 Nov;9(6):061102.
• Gilchrist KH, Lewis GF, Gay EA, Sellgren KL, Grego S. High-throughput cardiac safety evaluation and multi-parameter arrhythmia profiling of cardiomyocytes using microelectrode arrays. Toxicology and applied pharmacology. 2015 Oct;288(2):249u201357.
• Hawkins BT, Grego S, Sellgren KL. Three-dimensional culture conditions differentially affect astrocyte modulation of brain endothelial barrier function in response to transforming growth factor u03b21. Brain research. 2015 May;1608:167u201376.
• Sellgren KL, Butala EJ, Gilmour BP, Randell SH, Grego S. A biomimetic multicellular model of the airways using primary human cells. Lab on a chip. 2014 Sep;14(17):3349u201358.
• Gregory CW, Sellgren KL, Gilchrist KH, Grego S. Publisher's Note: "High yield fabrication of multilayer polydimethylsiloxane devices with freestanding micropillar arrays" [Biomicrofluidics 7, 056503 (2013)]. Biomicrofluidics. 2013 Nov 1;7(6).
• Scobey T, Yount BL, Sims AC, Donaldson EF, Agnihothram SS, Menachery VD, et al. Reverse genetics with a full-length infectious cDNA of the Middle East respiratory syndrome coronavirus. Proceedings of the National Academy of Sciences of the United States of America. 2013 Oct;110(40):16157u201362.
• Gregory CW, Sellgren KL, Gilchrist KH, Grego S. High yield fabrication of multilayer polydimethylsiloxane devices with freestanding micropillar arrays. Biomicrofluidics. 2013 Sep 6;7(5).
• Kim JY, Kwon MK, Vj L, Grego S, Saif Islam M. Postgrowth in situ chlorine passivation for suppressing surface-dominant transport in silicon nanowire devices. IEEE Transactions on Nanotechnology. 2012 Jul 17;11(4):782u20137.
• Gilchrist KH, Dausch DE, Grego S. Electromechanical performance of piezoelectric scanning mirrors for medical endoscopy. Sensors and Actuators A Physical. 2012 May 1;178:193u2013201.
• Grego S, Gilchrist KH, Carlson JB, Stoner BR. A compact and multichannel optical biosensor based on a wavelength interrogated input grating coupler. Sensors and Actuators B Chemical. 2012 Jan 3;161(1):721u20137.
• Grego S, Gilchrist KH, Kim JY, Kwon MK, Islam MS. Nanowire-based devices combining light guiding and photodetection. Applied Physics A Materials Science and Processing. 2011 Nov 1;105(2):311u20136.
• Grego S, Gilchrist KH, Stoner BR. Tunable wavelength interrogated sensor platform (TWIST) for point-of-care diagnostics of infectious diseases. In: Proceedings of SPIE the International Society for Optical Engineering. 2011.
• Vj L, Oh J, Nayak AP, Katzenmeyer AM, Gilchrist KH, Grego S, et al. A perspective on nanowire photodetectors: Current status, future challenges, and opportunities. IEEE Journal on Selected Topics in Quantum Electronics. 2011 Jul 1;17(4):1002u201332.
• Melvin EM, Moore BR, Gilchrist KH, Grego S, Velev OD. On-chip collection of particles and cells by AC electroosmotic pumping and dielectrophoresis using asymmetric microelectrodes. Biomicrofluidics. 2011 Jan 1;5(3).
• Kim JY, Kwon MK, Logeeswaran VJ, Grego S, Islam MS. In-situ chlorine passivation to suppress surface-dominant transport in silicon nanowire devices. In: Proceedings of SPIE the International Society for Optical Engineering. 2010.
• Grego S, Huffman A, Lueck M, Stoner BR, Lannon J. Nanoimprint lithography fabrication of waveguide-integrated optical gratings with inexpensive stamps. Microelectronic Engineering. 2010 Jan 1;87(10):1846u201351.
• Grego S, Gilchrist KH, Kim JY, Kwon MK, Islam MS. Waveguide-integrated nanowire photoconductors on a non-single crystal surface. In: Proceedings of SPIE the International Society for Optical Engineering. 2009.
• Bandaru PR, Grego S, Kinloch I. Materials Research Society Symposium Proceedings: Preface. In: Materials Research Society Symposium Proceedings. 2009.
• Gilchrist KH, McNabb RP, Izatt JA, Grego S. Piezoelectric scanning mirrors for endoscopic optical coherence tomography. Journal of Micromechanics and Microengineering. 2009 Nov 9;19(9).
• Piascik JR, Swift EJ, Thompson JY, Grego S, Stoner BR. Surface modification for enhanced silanation of zirconia ceramics. Dental materialsu202f: official publication of the Academy of Dental Materials. 2009 Sep;25(9):1116u201321.
• Grego S, Stoner BR. Wavelength interrogation of optical waveguide biosensors in the input grating coupler configuration. In: Proceedings of SPIE the International Society for Optical Engineering. 2009.
• Grego S, McDaniel JR, Stoner BR. Wavelength interrogation of grating-based optical biosensors in the input coupler configuration. Sensors and Actuators B Chemical. 2008 May 14;131(2):347u201355.
• Bhagat SK, Han H, Zoo Y, Lewis J, Grego S, Lee K, et al. Effects of deposition parameters on the electrical and mechanical properties of indium tin oxide films on polyethylene napthalate substrates deposited by radio frequency magnetron sputtering. Thin Solid Films. 2008 Apr 30;516(12):4064u20139.
• Lannon J, Grego S, Solomon S. Multicolor IR emissive pixels. In: Proceedings of SPIE the International Society for Optical Engineering. 2007.
• Grego S, Yang C, Bower CA, Stoner BR, Suleski TJ. Optical waveguide biosensor based on two-dimensional diffractive elements obtained by nano-imprint lithography. In: Proceedings of SPIE the International Society for Optical Engineering. 2007.
• Grego S, Lewis J, Vick E, Temple D. A method to evaluate mechanical performance of thin transparent films for flexible displays. Thin Solid Films. 2007 Apr 9;515(11):4745u201352.
• Bhagat S, Zoo Y, Han H, Lewis J, Grego S, Lee K, et al. Mechanical properties of indium tin oxide on polyethylene napthalate substrate. In: Materials Research Society Symposium Proceedings. 2007. p. 401u20136.
• Grego S, Patel AM, Stoner BR, Cao Y, Suleski TJ. Novel grating-based optical waveguide device for sensor applications. In: Proceedings of SPIE the International Society for Optical Engineering. 2006.
• Grego S, Naskar S, Patel AM, Huffman A, Bower CA, Stoner BR. Novel optical-waveguide sensing platform based on input grating coupler. In: Proceedings of SPIE the International Society for Optical Engineering. 2006.
• Lamvik M, Grego S. A multiaxis stage configured for rapid observations of plane samples at multiple angles. Review of Scientific Instruments. 2005 Dec 1;76(12):1u20133.
• Lamvik M, Grego S. Plano-eucentric photometry system for micro-display metrology. In: Digest of Technical Papers SID International Symposium. 2005. p. 542u20135.
• Lewis JS, Grego S, Vick E, Temple D. Evaluating and improving mechanical performance of thin films for flexible displays. In: Proceedings of SPIE the International Society for Optical Engineering. 2005. p. 249u201360.
• Bhatt KH, Grego S, Velev OD. An AC electrokinetic technique for collection and concentration of particles and cells on patterned electrodes. Langmuir. 2005 Jul 5;21(14):6603u201312.
• Grego S, Lewis J, Vick E, Temple D. Development and evaluation of bend-testing techniques for flexible-display applications. Journal of the Society for Information Display. 2005 Jul 1;13(7):575u201381.
• Grego S, Jarvis TW, Stoner BR, Lewis JS. Template-directed assembly on an ordered microsphere array. Langmuiru202f: the ACS journal of surfaces and colloids. 2005 May;21(11):4971u20135.
• Grego S, Lewis J, Vick E, Chalamala B, Temple D. Mechanical evaluation of permeation barriers for flexible OLED displays. In: Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS. 2004. p. 340u20131.
• Lamvik M, Grego S, Labennett R, Temple D. Polymer light guide arrays for tiling large-scale displays. In: Proceedings of SPIE - The International Society for Optical Engineering. 2004. p. 196u2013204.
• Lewis J, Grego S, Chalamala B, Vick E, Temple D. Highly flexible transparent electrodes for organic light-emitting diode-based displays. Applied Physics Letters. 2004 Oct 18;85(16):3450u20132.
• Grego S, Jarvis T, Stoner B, Lewis J. Investigation of the layer-by-layer assembly of colloid crystals on a templated substrate. In: Materials Research Society Symposium Proceedings. 2004. p. 345u201350.
• Lewis J, Grego S, Vick E, Chalamala B, Temple D. Mechanical performance of thin films in flexible displays. In: Materials Research Society Symposium Proceedings. 2004. p. 189u201398.
• Lamvik M, Grego S, Martin E, Fox D. Methods of automatic seamless tiling for rapid deployment of projection displays. In: Proceedings of SPIE the International Society for Optical Engineering. 2003. p. 272u20139.
• Lamvik M, Grego S, Martin E, Fox D. Rapid automatic alignment of a tiled digital projection system. In: Proceedings of SPIE the International Society for Optical Engineering. 2003. p. 7u201314.
• Foulger SH, Jiang P, Lattam A, Smith DW, Ballato J, Dausch DE, et al. Photonic crystal composites with reversible high-frequency stop band shifts. Advanced Materials. 2003 May 2;15(9):685u20139.
• Oddershede L, Dreyer JK, Grego S, Brown S, Berg-Su00f8rensen K. The motion of a single molecule, the lambda-receptor, in the bacterial outer membrane. Biophysical journal. 2002 Dec;83(6):3152u201361.
• Foulger SH, Lattam AC, Jiang P, Ballato J, Dausch DE, Grego S, et al. Integration of photonic bandgap composites with piezoelectric actuators for rejection wavelength tuning. In: Proceedings of SPIE the International Society for Optical Engineering. 2002. p. 40u201350.
• Tirnauer JS, Grego S, Salmon ED, Mitchison TJ. EB1-microtubule interactions in Xenopus egg extracts: role of EB1 in microtubule stabilization and mechanisms of targeting to microtubules. Molecular biology of the cell. 2002 Oct;13(10):3614u201326.
• Dowek D, Reiser I, Grego S, Andersen N, Dubois A, Houver JC, et al. P-state-to-P-state transitions in optically prepared atomic collisions: III. A complete analysis of Li+ + Na(3p) u2192 Li(2p) + Na+ differential scattering. Journal of Physics B Atomic Molecular and Optical Physics. 2002 May 14;35(9):2051u201368.
• Sidky EY, Grego S, Dowek D, Andersen N. P-state-to-P-state transitions in optically prepared atomic collisions: I. Theory of measurement in terms of Stokes parameters. Journal of Physics B Atomic Molecular and Optical Physics. 2002 May 14;35(9):2005u201333.
• Grego S, Salgado J, Borel P, Nielsen SE, Andersen N. P-state-to-P-state transitions in optically prepared atomic collisions: II. Alignment propensity for Na(3p) u2192 Li(2p) electron transfer. Journal of Physics B: Atomic, Molecular and Optical Physics. 2002 May 14;35(9):2035u201350.
• Oddershede L, Grego S, Nu00f8rrelykke SF, Berg-Su00f8rensen K. Optical tweezers: Probing biological surfaces. Probe Microscopy. 2001 Dec 1;2(2):129u201337.
• Grego S, Cantillana V, Salmon ED. Microtubule treadmilling in vitro investigated by fluorescence speckle and confocal microscopy. Biophysical journal. 2001 Jul;81(1):66u201378.
• Grego S, Salgado J, Thomsen JW, Machholm M, Nielsen SE, Andersen N. Final state alignment for Li+ + Na(3s) u2192 Li (2p) + Na+ electron transfer. Journal of Physics B Atomic Molecular and Optical Physics. 1998 Aug 14;31(15):3419u201328.
• Grego S, Arimondo E, Frediani C. Optical tweezers based on near infrared diode laser. Journal of Biomedical Optics. 1997 Jan 1;2(3):332u20139.
• Grego S, Colla M, Fioretti A, Mu00fcller JH, Verkerk P, Arimondo E. A cesium magneto-optical trap for cold collisions studies. Optics Communications. 1996 Dec 15;132(5u20136):519u201326.
• Frediani C, Grego S, Guidoni L, Arimondo E. Compact microscope-based 850-nm optical tweezers. In: Proceedings of SPIE the International Society for Optical Engineering. 1996. p. 56u201361.

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