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Publications

* indicates corresponding author, † indicates equal first authors, PPostdoc/research associate, GGraduate student, UUndergraduate student in the Ashkar Lab

  • "The Dynamic Face of Lipid Membranes", PS. Gupta and R. Ashkar*, Soft Matter (2021). Invited Review in the 2021 Soft Matter Emerging Investigators themed collection.
  • "Neutron Spin Echo Spectroscopy: A Unique Probe for Lipid Membrane Dynamics and Membrane-Protein Interactions", GT. Kumarage, UJ. Nguyen and R. Ashkar*, J. Vis. Exp. (2021). Invited Paper 
  • "The Universal Stiffening Effects of Cholesterol on Lipid Membranes", R. Ashkar*, M. Doktorova, F. A. Heberle, H. L. Scott, F. N. Barrera, J. Katsaras, G. Khelashvili, and M. F. Brown*,  Proc. Natl. Acad. Sci. (2021). Invited Letter
  • “Biomembrane Structure and Material Properties Studied with Neutron Scattering", J. Kinnun*, H.L. Scott*, R. Ashkar*, and J. Katsaras*, Front. Chem. (2021). Invited Review
  • “Scaling relationships for the elastic moduli and viscosity of mixed lipid membranes”, E.G. Kelley*, P. Butler, R. Ashkar, R. Bradbury, and M. Nagao, Proc. Natl. Acad. Sci. (2020). Article 
  • “How Cholesterol Stiffens Unsaturated Lipid Membranes”, PS. Chakraborty, M. Doktorova, T.R. Molugu, F.A. Heberle, H.L. Scott, B. Dzikovski, M. Nagao, L.-R. Stingaciu, R.F. Standaert, F. Barrera, J. Katsaras, G. Khelashvili, M.F. Brown*, and R. Ashkar*, Proc. Natl. Acad. Sci. (2020). Article 
  • “Selective dynamics in polymeric materials: Insights from quasi-elastic neutron scattering Spectroscopy”, R. Ashkar*, J. Appl. Phys. (2020). Invited Tutorial & Featured Article 
  • “Profile retrieval of a buried periodic structure using spin echo grazing incidence neutron scattering”, R. Ashkar*, R.M. Dalgliesh, R. Pynn, A.D.F. Dunbar, R.A.L. Jones, and A.J. Parnell*, Appl. Phys. Lett. (2020). Article 
  • “The Influence of Curvature on Domain Distribution in Binary Mixture Membranes”, W. Li, J. M. Carrillo*, J. Katsaras, B. Sumpter, R. Ashkar*, and R. Kumar*, Soft Matter 2019. Article & Back Cover 
  • "Neutron scattering in the biological sciences: progress and prospects", R. Ashkar, H.Z. Bilheux, H. Bordallo, R. Briber, D.J.E. Callaway, X. Cheng, . . . J.C. Smith. Acta Cryst. D74 1129-1168 74, 1129-1168. Lead Article
  • "Quantification of Carbon Nanotube Liquid Crystal Morphology via Neutron Scattering", Francesca Mirri, Rana Ashkar, Vida Jamali, Lucy Liberman, Robert A. Pinnick, Paul van der Schoot, Yeshayahu Talmon, Paul D. Butler, Matteo Pasquali Macromolecules 2018 51 (17), 6892-6900. Article
  • "Conformational Change and Suppression of the Θ-temperature for Solutions of Polymer-grafted Nanoparticles", K. I. S. Mongcopa, R. Poling-Skutvik, R. Ashkar, P. Butler, and R. Krishnamoorti. Soft Matter. 14, 6102-6108. Article
  • "Flexible Approach to Vibrational Sum-Frequency Generation Using Shaped Near-Infrared Light", A. U. Chowdhury, F. Liu, B. R. Watson, R. Ashkar, J. Katsaras, C. Patrick Collier, D. A. Lutterman, Y-Z Ma, T. R. Calhoun, and B. Doughty. Opt. Lett. 43, 2038-2041. Article
  • "Grating-Based Holographic Diffraction Methods for X-Rays and Neutrons: Phase Object Approximation and Dynamical Theory", H. Feng, R. Ashkar, N. Steinke, R. Dalgliesh, N.V. Lavrik, I. I. Kravchenko, and R. Pynn. J. Appl. Cryst. 51, 68-75. Article  
  • “Probing Elastic and Viscous Properties of Phospholipid Bilayers Using Neutron Spin Echo Spectroscopy”, M. Nagao*, E. G. Kelley, R. Ashkar, R. Bradbury, and P. D. Butler, J. Phys. Chem. Lett. 8 (19), 4679-4684. Article
  • “Rapid Large-Scale Assembly and Pattern Transfer of One-Dimensional Gold Nanorod Superstructures”, *R. Ashkar, *M. J. A. Hore, X. Ye, B. Natarajan, N. J. Greybush, T. Lam, C. R. Kagan, C. B. Murray, ACS Appl. Mater. Interfaces. 9 (30), 25513-25521. Article
  • “A Computational Approach to Model Neutron Scattering Data from Lipid Bilayers”, *J. M. Carrillo, J. Katsaras, B. Sumpter, and *R. Ashkar, J. Chem. Theory Comput. 13 (2), 916-925.  Article
  • “Unlocking the secrets of cell membranes”, R. Ashkar, EditorialACM SIGCAS Computers and Society Newsletter. 46 (2),  5-8. Article
  • “Multiscale metrologies for process optimization of carbon nanotube polymer composites”, B. Natarajan, N. Orloff, R. Ashkar, S. Doshi, K. Twedt, A. Krishnamurthy, C. Davis, A. M. Forster, E. Thostenson, J. Obrzut, R. Sharma, and J. A. Liddle*, Carbon. 108, 381- 393. Article
  • “Graphene nanocomposites with high molecular weight poly(ε-caprolactone) grafts: Controlled synthesis and accelerated crystallization”, †Titash Mondal, †R. Ashkar, P. Butler, A. Bhowmick* and Ramanan Krishnamoorti*, ACS Macro Lett. 5 (3), 278-282. Article
  • “Lightweight, flexible, high-performance carbon nanotube cables made by scalable flow coating”, Francesca Mirri, Nathan D. Orloff, R. Ashkar, A. Forster, C. Long, A. Bengio, A. Choi, Y. Luo, A. Hight Walker, P. Butler,  K. Migler, and M. Pasquali*, ACS Appl. Mater. Interfaces. 8 (7), 4903-4910. Article
  • “Kinetic polymer arrest in percolated SWNT networks, R. Ashkar*, M. Abdulbaki, M. Tyagi, A. Faraone, P. Butler and R. Krishnamoorti*, ACS Macro Lett. 3 (12). 1262-1265. Article
  • “A new approach for probing matter in periodic nanoconfinements using neutron scattering”, R. Ashkar*, R. Pynn, R. Dalgliesh, N. Lavrick, and I. Kravchenko. J. Appl. Cryst. 47. 1367-1373. Article
  • “Wetting-dewetting and dispersion-aggregation transitions are distinct for polymer grafted nanoparticles in chemically dissimilar polymer matrix”, †T. B. Martin, † K. I. Mongcopa, R. Ashkar, P. Butler, R. Krishnamoorti*, and Arthi Jayaraman*, J. Am. Chem. Soc. 137 (33), 10624-10631. Article
  • “Tuning membrane thickness fluctuations in model lipid bilayers”, R. Ashkar, Michihiro Nagao*, P. Butler, A. Woodka, M. K. Sen and T. Koga, Biophys. J. 109 (1), 106-112. Article
  • “Thermoresponsive PNIPAM coatings on nanostructured gratings for cell alignment and release”, †M. Zhernenkov*, †R. Ashkar*, H. Feng, O. Akintewe, N. D. Gallant, R. Toomey, J. F. Ankner, and R. Pynn, ACS Appl. Mater. Interfaces. 7 (22). 11857-11862. Article
  • “Dynamical Theory: Application to spin echo resolved grazing incidence scattering from periodic structures”, R. Ashkar*, W.L. Schaich, V. O. de Haan, A.A. van Well, R. Dalgliesh, J. Plomp, R. Pynn*. J. Appl. Phys. 110 (10). Article
  • “Comparison of dynamical theory and phase-object approximation on neutron scattering from periodic structures”, *R. Ashkar, V. O. de Haan, A.A. vanWell, R. Dalgliesh, J. Plomp, W.L. Schaich, and R. Pynn. J. Appl. Cryst. 44. 958-965Article
  • “Dynamical theory calculations of spin echo resolved grazing-incidence scattering from a diffraction grating”, R. Ashkar*, P. Stonaha, A. L.Washington, V. R. Shah, M. R. Fitzsimmons, B. Maranville, C. F. Majkrzak, W. T. Lee, W. L. Schaich, and R. Pynn*, J. Appl. Cryst. 43. 455- 465. Article