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Faculty Profile

Kevin E. BasslerKevin E. Bassler

Moores Professor of Physics and Mathematics
Department Chair
Department of Physics

Office: SR1-619C
Contact: bassler@uh.edu - (713) 743-3568

Education: Ph.D., Carnegie Mellon University

Complexity Theory and Non-Equilibrium Statistical Mechanics

The focus of my research is to understand and identify the fundamental principles that govern the dynamics of complex systems. I am interested in processes of growth, adaptation, self-organization, self-assembly, and evolution. Often, my approach is to construct simple models that capture the essence of experimental behavior of a class of systems and use them to explore the common features that underlie their dynamics. My work usually involves a combination of analytic calculations and computer simulations.

Much of my current interest is in the dynamics of systems organized as complex networks. The applications include physical, biological, social, and engineered systems. Specifically, projects of mine include developing algorithms and statistical approaches to optimally detect structure in complex networks as it relates to their dynamics and applying the methods to real-world biological and bio-medical networks, understanding adaptive or evolutionary behavior of complex networks, and understanding the role of symmetry and information flow in complex network dynamics. I am also interested in random matrix theory (RMT) and in applying RMT to understand the dynamics of networks.

Other interests of mine involve understanding the nature of anomalous diffusion and the behavior of materials systems, including the self-assembly of nano-structured arrays in semiconductor multilayers and the critical behavior of solids with extended defects.

Refereed Journal Articles

  1. K.E. Bassler, K. Sasaki, and R.B. Griffiths, 鈥淚nterface Interactions in Modulated Phases, and Upsilon Points,鈥 J. Stat. Phys. 62, 45-88 (1991).
  2. K.E. Bassler and M. Olvera de la Cruz, 鈥淢onte Carlo Study of Diblock Copolymers in Dilute Solution,鈥 J. de Physique I 3, 2387-2395 (1993).
  3. K.E. Bassler, B. Schmittmann, and R.K.P. Zia, 鈥淪patial Structures with Nonzero Winding Number in Biased Diffusion of Two Species,鈥 Europhys. Lett. 24, 115-120 (1993).
  4. K.E. Bassler and R.B. Griffiths, 鈥淣umerical Study of the Ground States of a New Type of Nonconvex Frenkel-Kontorova Model,鈥 Phys. Rev. B 49, 904-915 (1994).
  5. B. Schmittmann, K.E. Bassler, K. Hwang, and R.K.P. Zia, 鈥淏iased Diffusion of Two Species,鈥 Physica A 205, 284-291 (1994).
  6. K.E. Bassler and B. Schmittmann, 鈥淩enormalization Group Study of a Hybrid Driven Diffusive System,鈥 Phys. Rev. E 49, 3614-3620 (1994).
  7. K.E. Bassler and R.K.P. Zia, 鈥淧hase Transitions in a Nonequilibrium Potts Model: A Monte Carlo Study of Critical Behavior,鈥 Phys. Rev. E 49, 5871-5874 (1994).
  8. K.E. Bassler and Z. Racz, 鈥淏icritical Point and Crossover in a Two Temperature, Diffusive Kinetic Ising Model,鈥 Phys. Rev. Lett. 73, 1320-1323 (1994).
  9. K.E. Bassler and B. Schmittmann, 鈥淐ritical Dynamics of Nonconserved Ising-Like Systems,鈥 Phys. Rev. Lett. 73, 3343-3346 (1994).
  10. K.E. Bassler and Z. Racz, 鈥淓xistence of Long-Range Order in the Steady State of a Two Dimensional, Two-Temperature XY Model,鈥 Phys. Rev. E 52, R9-R12 (1995).
  11. K.E. Bassler and R.K.P. Zia, 鈥淧hase Transitions in a Driven Lattice Gas at Two Temperatures,鈥 J. Stat. Phys. 80, 499-515 (1995).
  12. B. Schmittmann and K.E. Bassler, 鈥淔rozen Disorder in a Driven System,鈥 Phys. Rev. Lett. 77, 3581-3584 (1996).
  13. K.E. Bassler and D.A. Browne, 鈥淣onequilibrium Critical Dynamics of a Three Species Monomer-Monomer Model,鈥 Phys. Rev. Lett. 77, 4094-4097 (1996).
  14. K.E. Bassler and D.A. Browne, 鈥淭he Three-Species Monomer-Monomer Model: A Mean-field Analysis and Monte Carlo Study,鈥 Phys. Rev. E 55, 5225-5233 (1997).
  15. K.S. Brown, K.E. Bassler and D.A. Browne, 鈥淢ean-field Analysis and Monte Carlo Study of an Interacting Two-Species Monomer-Monomer Model,鈥 Phys. Rev. E 56, 3953-3958 (1997).
  16. K.E. Bassler and D.A. Browne, 鈥淭he Three Species Monomer-Monomer Model in the Reaction-Controlled Limit,鈥 J. Phys. A: Math Gen. 31, 6309-6318 (1998).
  17. J. Trenkler, P.C. Chow, P. Wochner, H. Abe, K.E. Bassler, R. Paniago, H. Reichert, D. Scarfe, T.H. Metzger, J. Peisl, J. Bai, and S.C. Moss, 鈥淭wo Length Scales and Crossover Behavior in the Critical Diffuse Scattering from V2H,鈥 Phys. Rev. Lett. 81, 2276-2279 (1998).
  18. K.E. Bassler and M. Paczuski, 鈥淎 Simple Model of Superconducting Vortex Avalanches,鈥 Phys. Rev. Lett. 81, 3761-3764 (1998).
  19. K.E. Bassler, M. Paczuski, and G.F. Reiter, 鈥淏raided Rivers and Superconducting Vortex Avalanches,鈥 Phys. Rev. Lett. 83, 3956-3959 (1999).
  20. M. Paczuski, K.E. Bassler, and A. Corral, 鈥淪elf-Organized Networks of Competing Boolean Agents,鈥 Phys. Rev. Lett. 84, 3185-3189 (2000).
  21. M. Paczuski, and K.E. Bassler, 鈥淭heoretical Results for Sandpile Models of Self-Organized Criticality with Multiple Topplings,鈥 Phys. Rev. E 62, 5347-5352 (2000).
  22. J.R. Claycomb, K.E. Bassler, J.H. Miller, Jr., M. Nersesyan, and D. Luss, 鈥淎valanche Behavior in the Dynamics of Chemical Reactions,鈥 Phys. Rev. Lett. 87, 178303 (2001).
  23. K.E. Bassler, M. Paczuski, and E. Altshuler, 鈥淎 Simple Model for the Plastic Dynamics of a Disordered Flux Line Lattice,鈥 Phys. Rev. B 64, 224517 (2001).
  24. G.H. Gunarante, C.S. Rajapaksa, K.E. Bassler, K.K. Mohanty, and S.J. Wimalawansa, 鈥淎 Model for Bone Strength and Osteoporotic Fracture,鈥 Phys. Rev. Lett. 88, 068101 (2002).
  25. E. Altshuler, O. Ramos, A.J. Batista-Leyva, A. Rivera, and K.E. Bassler, 鈥淪andpile Formation by Revolving Rivers,鈥 Phys. Rev. Lett. 91, 014501 (2003).
  26. M. Anghel, Z. Toroczkai, K.E. Bassler, and G. Korniss 鈥淐ompetition-Driven Network Dynamics: Emergence of a Scale-free Leadership Structure and Collective Efficiency,鈥 Phys. Rev. Lett. 92, 058701 (2004).
  27. Z. Toroczkai and K.E. Bassler, 鈥淛amming is Limited in Scale-Free Networks,鈥 Nature 428, 716 (2004).
  28. K.E. Bassler, C. Lee, and Y. Lee, 鈥淓volution of Developmental Canalization in Networks of Competing Boolean Nodes,鈥 Phys. Rev. Lett. 93, 038101 (2004).
  29. E. Altshuler, T.H. Johansen, Y. Paltiel, P. Jin, K.E. Bassler, O. Ramos, G.F. Reiter, E. Zeldov, and C.W. Chu, 鈥淓xperiments in Superconducting Vortex Avalanches,鈥 Physica C 408, 501-504 (2004).
  30. E. Altshuler, T.H. Johansen, Y. Paltiel, P. Jin, K.E. Bassler, Q. Chen, O. Ramos, G.F. Reiter, E. Zeldov, and C.W. Chu, 鈥淰ortex Avalanches and Self Organized Criticality in Superconducting Niobium,鈥 Phys. Rev. B 70, Rapid Communications, 140505 (2004).
  31. J.H. Li, D.W. Stokes, O. Caha, S.L. Ammu, J. Bai, K.E. Bassler, and S.C. Moss, 鈥淢orphological Instability in InAs/GaSb Superlattices Due to Interfacial Bonds,鈥 Phys. Rev. Lett. 95, 096104 (2005).
  32. G. Korniss, M.B. Hastings, K.E. Bassler, M.J. Berryman, B. Kozma, and D. Abbott, 鈥淪caling in Small-World Resistor Networks,鈥 Phys. Letts. A 350, 324-330 (2006).
  33. A. Alejandro-Quinones, K.E. Bassler, M. Field, J.L. McCauley, M. Nicol, I. Timofeyev, A. Torok, and G. Gunaratne, 鈥淎 Theory of Fluctuations in Stock Prices,鈥 Physica A 363, 383-392 (2006).
  34. O. Caha, V. Holy, and K.E. Bassler, 鈥淣onlinear Evolution of Surface Morphology in InAs/AlAs Superlattices via Surface Diffusion,鈥 Phys. Rev. Letts. 96, 136102 (2006).
  35. K.E. Bassler, G.H. Gunaratne, and J.L. McCauley, 鈥淢arkov Processes, Hurst Exponents, and Nonlinear Diffusion Equations,鈥 Physica A 369, 343-353 (2006).
  36. B. Danila, Y. Yu, S. Earl, J.A. Marsh, Z. Toroczkai, and K.E. Bassler, 鈥淐ongestion-Gradient Driven Transport on Complex Networks,鈥 Phys. Rev. E 74, 046114 (2006).
  37. M. Liu and K.E. Bassler, 鈥淓mergent Criticality from Coevolution in Random Boolean Networks,鈥 Phys. Rev. E 74, 041910 (2006).
  38. B. Danila, Y. Yu, J.A. Marsh and K.E. Bassler, 鈥淥ptimal Transport on Complex Networks,鈥 Phys. Rev. E 74, 046106 (2006).
  39. J.L. McCauley, G.H. Gunaratne, and K.E. Bassler, 鈥淗urst Exponents, Markov Processes, and Fractal Brownian Motion,鈥 Physica A 379, 1-9 (2007).
  40. C.J. Olsen Reichhardt, and K.E. Bassler, 鈥淐analization and Symmetry in Boolean Models for Genetic Regulatory Networks,鈥 J. Phys. A: Math. Theor. 40, 4339 (2007).
  41. J.L. McCauley, G.H. Gunaratne, and K.E. Bassler, 鈥淢artingale Option Pricing,鈥 Physica A 380, 351-356 (2007).
  42. B. Danila, Y. Yu, J.A. Marsh and K.E. Bassler, 鈥淭ransport Optimization on Complex Networks,鈥 Chaos 17, 026102 (2007).
  43. Y. Yu, B. Danila, J.A. Marsh and K.E. Bassler, 鈥淭ransport Optimization on Wireless Networks,鈥 Europhys. Lett. 79, 48004 (2007).
  44. K.E. Bassler, J.L. McCauley, and G.H. Gunaratne, 鈥淣onstationary Increments, Scaling Distributions, and Variable Diffusion Processes in Financial Markets,鈥 Proc. Nat. Acad. Sci. USA 104, 17287-17290 (2007).
  45. J.L. McCauley, K.E. Bassler, and G.H. Gunaratne, 鈥淢artingales, Detrending Data, and the Efficient Market Hypothesis,鈥 Physica A 387, 202-216 (2008).
  46. K.E. Bassler, G.H. Gunaratne, and J.L. McCauley, 鈥淒ynamics of Real Financial Markets: A Response to Frank鈥檚 Comment,鈥 Physica A 387, 3239-3241 (2008).
  47. J.L. McCauley, K.E. Bassler, and G.H. Gunaratne, 鈥淢artingales, Nonstationary Increments, and the Efficient Market Hypothesis,鈥 Physica A 387, 3916-3920 (2008).
  48. Z. Toroczkai, B. Kozma, K.E. Bassler, N.W. Hengartner, and G. Korniss, 鈥淕radient Networks,鈥 J. Phys. A: Math. Theor. 41, 155103 (2008).
  49. K.E. Bassler, G.H. Gunaratne, and J.L. McCauley, 鈥淓mpirically Based Modeling in Finance and Beyond and Spurious Stylized Facts,鈥 Int. Rev. Fin. Anal. 17, 767-783 (2008).
  50. K.E. Bassler, P.J. Forrester, and N.E. Frankel, 鈥淓igenvalue Separation in Some Random Matrix Models,鈥 J. Math. Phys. 50, 033302 (2009).
  51. J.L. McCauley, G.H. Gunaratne, and K.E. Bassler, 鈥淚s Integration I(d) applicable to observed economics and financial time series,鈥 Int. Rev. Fin. Anal. 18, 101-108 (2009).
  52. Y. Sun, B. Danila, K. Josic, and K.E. Bassler, 鈥淚mproved community structure detection using a modified fine tuning strategy,鈥 EPL 86, 28004 (2009).
  53. C.I. Del Genio, J. Trenkler, K.E. Bassler, P. Wochner, D.R. Haeffner, G.F. Reiter, J. Bai, and S.C. Moss, 鈥淒epth-dependent critical behavior in V2H,鈥 Phys. Rev. B 79, 184113 (2009).
  54. B. Danila, Y. Sun, and K.E. Bassler, 鈥淐ollectively optimal routing for link capacity limited congested traffic,鈥 Phys. Rev. E 80, 066116 (2009).
  55. C.I. Del Genio, K.E. Bassler, A.L. Korzhenevskii, R.I. Barabash, J. Trenkler, G.F. Reiter, and S.C. Moss, 鈥淒epth-dependent ordering, two length-scale phenomena, and crossover behavior in a crystal featuring a skin-layer with defects,鈥 Phys. Rev. B 81, 144111 (2010).
  56. C.I. Del Genio, H. Kim, Z. Toroczkai, and K.E. Bassler, 鈥淓fficient and Exact Sampling of Simple Graphs with Arbitrary Given Degree Sequence,鈥 PLoS ONE 5, e10012 (2010).
  57. J.H. Li, D.W. Stokes, J.C. Wickett, O. Caha, K.E. Bassler, and S.C. Moss, 鈥淓ffect of Strain on the Growth of InAs/GaSb Superlattices: An X-Ray Study,鈥 J. Appl. Phys. 107, 123504 (2010).
  58. C.I. Del Genio and K.E. Bassler, 鈥淎nomalous ordering in inhomogeneously strained materials,鈥 Phys. Rev. E 82, 031115 (2010).
  59. M.D. Reichl, C.I. Del Genio and K.E. Bassler, 鈥淧hase diagram for a two-dimensional, twotemperature, diffusive XY model,鈥 Phys. Rev. E 82, 040102 (2010), Rapid Communication.
  60. K.E. Bassler, P.J. Forrester, and N.E. Frankel, 鈥淓dge effects in some perturbations of the Gaussian unitary ensemble,鈥 J. Math. Phys. 51, 123305 (2010).
  61. M. Liu and K.E. Bassler, 鈥淔inite Size Effects and Symmetry Breaking in the Evolution of Networks of Competing Boolean Nodes,鈥 J. Phys. A: Math. Theor. 44, 045101 (2011).
  62. C.I. Del Genio, T. Gross, and K.E. Bassler, 鈥淎ll scale-free networks are sparse,鈥 Phys. Rev. Lett. 107, 178701 (2011).
  63. M.D. Reichl and K.E. Bassler, 鈥淐analization in the critical states of highly connected networks of competing Boolean nodes,鈥 Phys. Rev. E. 84, 056103 (2011).
  64. H. Kim, C.I. Del Genio, K.E. Bassler, and Z. Toroczkai, 鈥淐onstructing and sampling directed graphs with given degree sequence,鈥 New J. Phys. 14, 023012 (2012).
  65. S. Trevino III, Y. Sun, T.F. Cooper, and K.E. Bassler, 鈥淩obust detection of hierarchical communities from Escherichia coli gene expression data,鈥 PLoS Comput. Biol. 8, e1002391 (2012).
  66. S.K. Bhavnani, G. Bellala, S. Victor, K.E. Bassler, and S. Visweswaran, 鈥淭he role of complementary bipartite visual analytical representation in the analysis of SNPs: A case study in ancestral informative markers,鈥 J. Am. Med. Infom. Assoc. 19, e5 (2012).
  67. 67. B. Li, J. Li, K.E. Bassler, and C.S. Ting, 鈥淢agnetic and superconducting structures near twin boundaries in low doped Fe-pnictides,鈥 New J. Phys. 15, 103018 (2013).
  68. S. Hossein, M.D. Reichl, and K.E. Bassler, 鈥淪ymmetry in Critical Random Boolean Network Dynamics,鈥 Phys. Rev. E 89, 042808 (2014).
  69. S. Trevino, A. Nyberg, C.I. Del Genio, and K.E. Bassler, 鈥淔ast and accurate determination of modularity and its effect size,鈥 J. Stat. Mech.: Theo. and Exper. P02003 (2015).
  70. A. Nyberg, T. Gross, and K.E. Bassler, 鈥淢esoscale structures and the Laplacian spectra of random geometic graphs,鈥 J. Complex Networks 3, 543-551 (2015).
  71. K.E. Bassler, W. Liu, B. Schmittmann, and R.K.P. Zia, 鈥淓xtreme Thouless effect in a minimal model of dynamic social networks,鈥 Phys. Rev. E 91, 042102 (2015).
  72. B. Li, L.H. Pan, Y.Y. Tai, M.J. Graf, J.X. Zhu, K.E. Bassler, and C.S. Ting, 鈥淯nified description of superconducting pairing symmetry in electron-doped Fe-based-122 compounds,鈥 Phys. Rev. B 91, 220509 (2015).
  73. K.E. Bassler, D. Dhar, and R.K.P. Zia, 鈥淣etworks with preferred degree: a mini-review and some new results,鈥 J. Stat. Mech.: Theo. and Exper. P07013 (2015).
  74. K.E. Bassler, C.I. Del Genio, P.L. Erdos, I. Miklos, and Z. Toroczkai, 鈥淓xact sampling of graphs with prescribed degree correlations,鈥 New J. Phys. 17, 083052 (2015).
  75. C. Orsini, M.M. Dankulov, P. Colomer-de-Simon, A. Jamakovic, P. Mahadevan, A. Vahdat, K.E. Bassler, Z. Toroczkai, M. Boguna, G. Caldarelli, S. Fortunato, and D. Krioukov, 鈥淨uantifying randomness in real networks,鈥 Nature Comm. 6, 8627 (2015).
  76. R. Chauhan, J. Ravi, P. Datta, T. Chen, D. Schnappinger, K.E. Bassler, G. Balazsi, and M.L. Gennaro, 鈥淩econstruction and topological characterization of the sigma factor regulatory network of Mycobacterium tuberculosis,鈥 Nature Comm. 7, 11062 (2016).
  77. Y.Y. Zhou, B. Li, W. Li, H.Y. Chen, K.E. Bassler, and C.S. Ting, 鈥淓ffects of single- and multisubstituted Zn ions in doped 122-type iron-based superconductors,鈥 Phys. Rev. B 93, 144510 (2016).
  78. L. Chen, K.E. Bassler, J.L. McCauley, and G.H. Gunaratne, 鈥淎nomalous scaling of stochastic processes and the Moses effect,鈥 Phys. Rev. E 95, 042141 (2017).
  79. K.E. Bassler and R.K.P. Zia, 鈥淓mergence of a spectral gap in a class of random matrices associated with split graphs,鈥 J. Phys. A 51, 014002 (2018).
  80. T. Chen, P. Singh and K.E. Bassler, 鈥淣etwork community detection using modularity density measures,鈥 J. Stat. Mech.: Theo. and Exper. 053406 (2018).
  81. S. Stolarczyk, M. Bhardwaj, K.E. Bassler, W.J. Ma and K. Josic, 鈥淟oss of information in feedforward social networks,鈥 J. Complex Networks 6, 448-469 (2018).
  82. S.K. Bhavnani, B. Dang, S. Visweswaran, K.E. Bassler, T. Chen, M. Raji, R. Divekar, A. Karmarkar, A. Tan, Y.-F. Kuo, and K. Ottenbacher, 鈥淗ow high-risk comorbidites co-occur in readmitted hip fracture patients: Implications for precision medicine and predictive modeling,鈥 preprint.
  83. T. Paixao, K.E. Bassler, and R. Azevedo, 鈥淓mergent speciation by multiple Dobzhansky-Muller incompatibilities,鈥 preprint, .
  84. P. Meyer, V. Adlakha, H. Kantz, and K.E. Bassler, 鈥淎nomalous diffusion and the Moses effect in a model of aging,鈥 preprint, .
  85. K.E. Bassler, E. Frey and R.K.P. Zia, 鈥淐o-evolution of nodes and links: diversity driven co-existence in cyclic competition of three species,鈥 preprint, .
  86. R.K.P. Zia, W. Zhang, M. Ezzatabadipour, and K.E. Bassler, 鈥淓xact results for the extreme Thouless effect in a model of network dynamics,鈥 preprint.

Book Chapters and Conference Proceedings

  1. K.E. Bassler, 鈥淐ritical Properties of Nonequilibrium Ising Systems,鈥 in Computer Simulation Studies in Condensed Matter Physics VII, eds. D.P. Landau, K.K. Mon, and H.-B. Schuttler, (Springer-Verlag, 1994).
  2. K.E. Bassler and M. Paczuski, 鈥淐ellular Model of Superconducting Vortex Dynamics,鈥 in Complexity from Microscopic to Macroscopic Scales: Coherence and Large Deviations, A. Skjeltorp, ed. (Kluwer Academic Publishers, Dordrecht, 2001).
  3. M. Anghel, Z. Toroczkai, G. Korniss, and K.E. Bassler, 鈥淓ffect of Inter-Agent Communication on the Collective,鈥 in Collectives and the Design of Complex Systems, K. Turner and D.H. Wolpert, eds., (Springer, 2003).
  4. T.J. Vadakkan and K.E. Bassler, 鈥淧hase Diagram and Clustering in an Anisotropic 3D Sandpile Model of Vortex Motion,鈥 Proc. SPIE 5845, 72 (2005).
  5. K.E. Bassler and M. Liu, 鈥淓ffects of Stochastic Noise on the Evolution of Canalization,鈥 Invited paper, Proc. SPIE 5845, 104 (2005).
  6. A.L. Alejandro-Quinones, K.E. Bassler, J.L. McCauley, and G. Gunaratne, 鈥淎 Theory of Fluctuations in Stock Prices: Effects of Discreteness,鈥 Proc. SPIE 5848, 27 (2005).
  7. J.L. McCauley, G.H. Gunaratne, and K.E. Bassler, 鈥淲hat Economists Should Learn from Econophysics,鈥 in Dynamics of Complex Interconnected Systems, Networks and Bioprocesses, A. Skjeltorp and A. Belyushkin, eds., (Springer, 2005).
  8. K.E. Bassler and O. Caha, 鈥淣onlinear Evolution of Surface Morphology in Short-Period Superlattices,鈥 in Diffuse Scattering in the 21st Century: Emerging Insights into Materials Structure and Behavior, (Momentum Press, 2009).
  9. D. Dhar, K.E. Bassler, and R.K.P. Zia, 鈥淭he many-agent limit of the Extreme Introvert-Extrovert model,鈥 in Econophysics and Sociophysics: Recent Progress and Future Directions, F. Abergel, H. Aoyama, B.K. Chakrabarti, A. Chakraborti, N. Deo, D. Raina, and I. Vodenska, eds. (Springer, 2017).

Reduced Network Extremal Ensemble Learning (RenEEL)

RenEEL is an algorithmic scheme for finding the network partition with maximum modularity, which is a challenging, NP-hard computational problem. It uses a Machine Learning method we call Extremal Ensemble Learning (EEL). The underlying idea of RenEEL is to first find an ensemble of partitions, then use information within the ensemble to efficiently find a new partition that is used to update the ensemble using extremal criteria. The updating continues until a consensus about what the best partition is is reached. Tests on benchmark networks have shown that RenEEL outperforms all other known methods for maximizing modularity.

RenEEL is a powerful and versatile scheme. It uses a conventional algorithm to find network partitions to create and update the ensemble. The C code in the GitHub respository linked to below uses a fast greedy agglomeration algorithm for this purpose, but any conventional algorithm could be used. RenEEL is presented in Scientific Reports 9, 14234 (2019). Please cite that paper if you use the code, or some version of it.