Associate Professor Eric Vanman
Associate Professor
School of Psychology
+61 7 336 56213
Researcher biography
Eric J. Vanman is an Associate Professor in the School of Psychology at the University of Queensland Australia. After receiving his Ph.D. in social psychology from the University of Southern California in 1994, he was a post-doctoral fellow in cognitive and behavioral neuroscience at USC and then spent a year as a research scientist at Texas A&M University. He was then a lecturer at Emory University until his appointment as an Assistant Professor at Georgia State University in 2000. He left Georgia State in 2007 as an Associate Professor to take up his current position. His research interests include the social neuroscience of emotion and intergroup prejudice, and his studies have incorporated several kinds of psychophysiological and neuroimaging methods.
Publications
Book
Blascovich, Jim, Vanman, Eric J., Mendes, Wendy Berry and DIckerson, Sally (2011). Social psychophysiology for social and personality psychology. Los Angeles, CA, United States: Sage Publications.
Book Chapters
Vanman, Eric J. (2023). The intragroup level. The Routledge International Handbook of the Psychology of Morality. (pp. 168-178) London: Routledge. doi: 10.4324/9781003125969-26
McGovern, Hugh T. and Vanman, Eric J. (2022). Gene by environment interactions in intergroup relations. The neuroscience of intergroup relations: global perspectives on the neural underpinnings of intergroup behaviour, ingroup bias and prejudice. (pp. 76-94) edited by Pascal Molenberghs. Abingdon, Oxon, United Kingdom: Routledge. doi: 10.4324/9781003042426-6
Kappas, Arvid, Stower, Rebecca and Vanman, Eric J. (2020). Communicating with robots: what we do wrong and what we do right in artificial social intelligence, and what we need to do better. Social intelligence and nonverbal communication. (pp. 233-254) edited by Robert J. Sternberg and Aleksandra Kostić. Cham, Switzerland: Palgrave Macmillan. doi: 10.1007/978-3-030-34964-6_8
Vanman, Eric J. and Philipp, Michael C. (2019). Physiological Measures. Advanced Research Methods for the Social and Behavioral Sciences. (pp. 147-167) edited by John E Edlund and Austin Lee Nichols. Cambridge, United Kingdom: Cambridge University Press.
Tassinary, Louis G., Cacioppo, John T. and Vanman, Eric J. (2017). The somatic system. Handbook of Psychophysiology. (pp. 151-182) edited by John T. Cacioppo, Louis G. Tassinary and Gary G. Berntson. Cambridge, United Kingdom: Cambridge University Press. doi: 10.1017/9781107415782.008
Owren, Michael J., Philipp, Michael, Vanman, Eric, Trivedi, Niyati, Schulman, Allison and Bachorowski, Jo-Anne (2013). Understanding spontaneous human laughter: the role of voicing in inducing positive emotion. Evolution of emotional communication: from sounds in nonhuman mammals to speech and music in man. (pp. 175-190) edited by Eckart Altenmuller, Sabine Schmidt and Elke Zimmermann. Oxford, United Kingdom: Oxford University Press.
Tassinary, L. G., Cacioppo, J. T. and Vanman, E. J. (2007). The skeletomotor system: Surface electromyography. Handbook of Psychophysiology. (pp. 267-299) edited by J. T. Cacioppo, L. G. Tassinary and G. G. Berntson. New York: Cambridge University Press.
Journal Articles
McComb, Carly A., Vanman, Eric J. and Tobin, Stephanie J. (2023). A meta-analysis of the effects of social media exposure to upward comparison targets on self-evaluations and emotions. Media Psychology, 26 (5), 612-635. doi: 10.1080/15213269.2023.2180647
Gamble, Roger S., Henry, Julie D. and Vanman, Eric J. (2023). Empathy moderates the relationship between cognitive load and prosocial behaviour. Scientific Reports, 13 (1) 824, 1-10. doi: 10.1038/s41598-023-28098-x
Nitschke, Faye T., McKimmie, Blake M. and Vanman, Eric J. (2022). The effect of heuristic cues on jurors' systematic information processing in rape trials. Psychology of Women Quarterly, 46 (4), 484-500. doi: 10.1177/03616843221118018
Nitschke, Faye T., McKimmie, Blake M. and Vanman, Eric J. (2022). The effect of heuristic cues on jurors’ systematic information processing in rape trials. Psychology of Women Quarterly, 46 (4), 1-17. doi: 10.1177/03616843221118018
Nitschinsk, Lewis, Tobin, Stephanie J. and Vanman, Eric J. (2022). The dark triad and online self-presentation styles and beliefs. Personality and Individual Differences, 194 111641, 111641. doi: 10.1016/j.paid.2022.111641
Nitschinsk, Lewis, Tobin, Stephanie J. and Vanman, Eric J. (2022). The disinhibiting effects of anonymity increase online trolling. Cyberpsychology, Behavior, and Social Networking, 25 (6), 377-383. doi: 10.1089/cyber.2022.0005
Nitschke, Faye T., McKimmie, Blake M. and Vanman, Eric J. (2022). The effect of trauma education judicial instructions on decisions about complainant credibility in rape trials. Psychology, Public Policy, and Law, 29 (1), 69-92. doi: 10.1037/law0000353
Sung, Billy, Vanman, Eric J. and Hartley, Nicole (2022). Revisiting (dis)fluency: metacognitive difficulty as a novelty cue that evokes feeling-of-interest. Psychology and Marketing, 39 (8), 1451-1466. doi: 10.1002/mar.21664
Sung, Billy, Hartley, Nicole, Vanman, Eric and Hooshmand, Reyhane (2021). Objective vs subjective design newness. Asia Pacific Journal of Marketing and Logistics, ahead-of-print (ahead-of-print), 1482-1502. doi: 10.1108/apjml-12-2020-0897
Zickfeld, Janis H., van de Ven, Niels, Pich, Olivia, Schubert, Thomas W., Berkessel, Jana B., Pizarro, José J., Bhushan, Braj, Mateo, Nino Jose, Barbosa, Sergio, Sharman, Leah, Kökönyei, Gyöngyi, Schrover, Elke, Kardum, Igor, Aruta, John Jamir Benzon, Lazarevic, Ljiljana B., Escobar, María Josefina, Stadel, Marie, Arriaga, Patrícia, Dodaj, Arta, Shankland, Rebecca, Majeed, Nadyanna M., Li, Yansong, Lekkou, Eleimonitria, Hartanto, Andree, Özdoğru, Asil A., Vaughn, Leigh Ann, del Carmen Espinoza, Maria, Caballero, Amparo, Kolen, Anouk ... Vingerhoets, Ad (2021). Tears evoke the intention to offer social support: a systematic investigation of the interpersonal effects of emotional crying across 41 countries. Journal of Experimental Social Psychology, 95 104137, 104137. doi: 10.1016/j.jesp.2021.104137
Philipp, Michael C., Bernstein, Michael J., Vanman, Eric J. and Johnston, Lucy (2021). Social exclusion enhances affiliative signaling. Journal of Social Psychology, 161 (4), 1-11. doi: 10.1080/00224545.2020.1854648
Grainger, Sarah A., Mead, Jessica K., Vanman, Eric J. and Henry, Julie D. (2021). The relationship between testosterone and social cognition in younger and older adults. Biological Psychology, 161 108072, 1-5. doi: 10.1016/j.biopsycho.2021.108072
Vanman, Eric J., Kappas, Arvid and Ito, Tiffany A. (2021). Social neuroscience is more than the study of the human brain: the legacy of John Cacioppo. Social Neuroscience, 16 (1), 1-5. doi: 10.1080/17470919.2021.1879459
Grainger, Sarah A., Vanman, Eric J. and Henry, Julie D. (2020). Tears of sadness reduce others' gazing toward the eyes. Emotion, 22 (6), 1382-1386. doi: 10.1037/emo0000926
Gallois, Cindy, Vanman, Eric J., Kalokerinos, Elise K. and Greenaway, Katharine H. (2020). Emotion and its management: the lens of language and social psychology. Journal of Language and Social Psychology, 40 (1), 0261927X2096672-59. doi: 10.1177/0261927x20966722
Larwood, Joel L., Vanman, Eric J. and Dingle, Genevieve A. (2020). Negative valence specific deficits in judgements of musical affective quality in alexithymia. Cognition and Emotion, 35 (3), 1-10. doi: 10.1080/02699931.2019.1707514
McGovern, H. T. and Vanman, Eric John (2020). Pathogens and intergroup relations. How evolutionary approaches can inform social neuroscience. Evolutionary Psychological Science, 7 (2), 200-210. doi: 10.1007/s40806-020-00269-3
Sommer, Kristyn, Nielsen, Mark, Draheim, Madeline, Redshaw, Jonathan, Vanman, Eric J. and Wilks, M. (2019). Children's perceptions of the moral worth of live agents, robots, and inanimate objects. Journal of Experimental Child Psychology, 187 104656, 1-22. doi: 10.1016/j.jecp.2019.06.009
Sharman, Leah S., Dingle, Genevieve A., Baker, Marc, Fischer, Agneta, Gračanin, Asmir, Kardum, Igor, Manley, Harry, Manokara, Kunalan, Pattara-Angkoon, Sirirada, Vingerhoets, Ad J. J. M. and Vanman, Eric J. (2019). The relationship of gender roles and beliefs to crying in an international sample. Frontiers in Psychology, 10 2288, 2288. doi: 10.3389/fpsyg.2019.02288
Nitschke, Faye T., McKimmie, Blake M. and Vanman, Eric J. (2019). A Meta-Analysis of the Emotional Victim Effect for Female Adult Rape Complainants: Does Complainant Distress Influence Credibility?. Psychological Bulletin, 145 (10), 953-979. doi: 10.1037/bul0000206
Vanman, Eric J. and Kappas, Arvid (2019). “Danger, Will Robinson!” The challenges of social robots for intergroup relations. Social and Personality Psychology Compass, 13 (8) e12489. doi: 10.1111/spc3.12489
Sharman, Leah S., Dingle, Genevieve A., Vingerhoets, Ad J. J. M. and Vanman, Eric J. (2019). Using crying to cope: physiological responses to stress following tears of sadness. Emotion, 20 (7), 1279-1291. doi: 10.1037/emo0000633
Sung, Billy, Vanman, Eric and Hartley, Nicole (2019). Interest, but not liking, drives consumer preference toward novelty. Australasian Marketing Journal, 27 (4), 242-248. doi: 10.1016/j.ausmj.2019.06.003
Grainger, Sarah A., Vanman, Eric J., Matters, Gabriella and Henry, Julie D. (2019). The influence of tears on older and younger adults' perceptions of sadness. Psychology and Aging, 34 (5), 665-673. doi: 10.1037/pag0000373
Grainger, Sarah A., Henry, Julie D., Steinvik, Henriette R. and Vanman, Eric J. (2018). Intranasal oxytocin does not alter initial perceptions of facial trustworthiness in younger or older adults. Journal of Psychopharmacology , 33 (2), 026988111880630-254. doi: 10.1177/0269881118806303
Sharman, Leah S., Dingle, Genevieve A. and Vanman, Eric J. (2018). Does crying help? Development of the beliefs about crying scale (BACS). Cognition and Emotion, 33 (4), 1-15. doi: 10.1080/02699931.2018.1488243
Vanman, Eric, Baker, Rosemary and Tobin, Stephanie (2018). The burden of online friends: the effects of giving up Facebook on stress and well-being. The Journal of Social Psychology, 158 (4), 496-507. doi: 10.1080/00224545.2018.1453467
Tsankova, Elena, Vanman, Eric J. and Kappas, Arvid (2018). Interaction of stereotypical trustworthiness, facial resemblance, and group membership in the perception of trustworthiness and other traits. Journal of Trust Research, 8 (1), 31-44. doi: 10.1080/21515581.2018.1453824
Grainger, Sarah A., Henry, Julie D., Steinvik, Henriette R., Vanman, Eric J., Rendell, Peter G. and Labuschagne, Izelle (2018). Intranasal oxytocin does not reduce age-related difficulties in social cognition. Hormones and Behavior, 99, 25-34. doi: 10.1016/j.yhbeh.2018.01.009
Cui, Qian, Vanman, Eric J., Long, Zhiliang, Pang, Yajing, Chen, Yuyan, Wang, Yifeng, Duan, Xujun, Chen, Heng, Gong, Qiyong, Zhang, Wei and Chen, Huafu (2017). Social anxiety disorder exhibit impaired networks involved in self and theory of mind processing. Social Cognitive and Affective Neuroscience, 12 (8), 1284-1295. doi: 10.1093/scan/nsx050
Vartanian, Lenny R., Trewartha, Tara, Beames, Joanne R., Azevedo, Suzanna M. and Vanman, Eric J. (2017). Physiological and self-reported disgust reactions to obesity. Cognition and Emotion, 32 (3), 1-14. doi: 10.1080/02699931.2017.1325728
Sung, Billy, Vanman, Eric J., Hartley, Nicole and Phau, Ian (2016). The emotion of interest and its relevance to consumer psychology and behaviour. Australasian Marketing Journal, 24 (4), 337-343. doi: 10.1016/j.ausmj.2016.11.005
Vanman, Eric J. (2016). The role of empathy in intergroup relations. Current Opinion in Psychology, 11, 59-63. doi: 10.1016/j.copsyc.2016.06.007
Sung, Billy, Hartley, Nicole, Vanman, Eric and Phau, Ian (2016). How can the word "NEW" evoke consumers' experiences of novelty and interest?. Journal of Retailing and Consumer Services, 31, 166-173. doi: 10.1016/j.jretconser.2016.02.010
Vartanian, Lenny R., Trewartha, Tara and Vanman, Eric J. (2016). Disgust predicts prejudice and discrimination toward individuals with obesity. Journal of Applied Social Psychology, 46 (6), 369-375. doi: 10.1111/jasp.12370
Loftus, Andrea M, Yalcin, Ozgur, Baughman, Frank D, Vanman, Eric J and Hagger, Martin S (2015). The impact of transcranial direct current stimulation on inhibitory control in young adults. Brain and Behavior, 5 (5) e00332, n/a-n/a. doi: 10.1002/brb3.332
Grainger, Sarah A., Henry, Julie D., Phillips, Louise H., Vanman, Eric J. and Allen, Roy (2015). Age deficits in facial affect recognition: the influence of dynamic cues. Journals of Gerontology Series B: Psychological Sciences and Social Sciences, 72 (4), 622-632. doi: 10.1093/geronb/gbv100
Cowan, David G., Vanman, Eric J. and Nielsen, Mark (2014). Motivated empathy: the mechanics of the empathic gaze. Cognition and Emotion, 28 (8), 1522-1530. doi: 10.1080/02699931.2014.890563
Iyer, Aarti, Webster, Joanna, Hornsey, Matthew J. and Vanman, Eric J. (2014). Understanding the power of the picture: the effect of image content on emotional and political responses to terrorism. Journal of Applied Social Psychology, 44 (7), 511-521. doi: 10.1111/jasp.12243
Iyer, Aarti, Hornsey, Matthew J., Vanman, Eric J., Esposo, Sarah and Ale, Shalini (2014). Fight and flight: evidence of aggressive capitulation in the face of fear messages from terrorists. Political Psychology, 36 (6), 631-648. doi: 10.1111/pops.12182
Tobin, Stephanie J., Vanman, Eric J., Verreynne, Marnize and Saeri, Alexander K. (2014). Threats to belonging on Facebook: lurking and ostracism. Social Influence, 10 (1), 31-42. doi: 10.1080/15534510.2014.893924
Vartanian, Lenny R., Thomas, Margaret A. and Vanman, Eric J. (2013). Disgust, contempt, and anger and the stereotypes of obese people. Eating and Weight Disorders: Studies on Anorexia, Bulimia and Obesity, 18 (4), 377-382. doi: 10.1007/s40519-013-0067-2
Vanman, Eric J., Ryan, John P., Pedersen, Wiliam C. and Ito, Tiffany A. (2013). Probing prejudice with startle eyeblink modification: A marker of attention, emotion, or both?. International Journal of Psychological Research, 6 (Special Issue), 30-41. doi: 10.21500/20112084.717
Cui, Qian, Vanman, Eric J., Wei, Dongtao, Yang, Wenjing, Jia, Lei and Zhang, Qinglin (2013). Detection of deception based on fMRI activation patterns underlying the production of a deceptive response and receiving feedback about the success of the deception after a mock murder crime. Social Cognitive and Affective Neuroscience, Advance Access (10) nst134, 1-9. doi: 10.1093/scan/nst134
Milston, Sashenka I., Vanman, Eric J. and Cunnington, Ross (2013). Cognitive empathy and motor activity during observed actions. Neuropsychologia, 51 (6), 1103-1108. doi: 10.1016/j.neuropsychologia.2013.02.020
Stewart, Tracie L., Amoss, R. Toby, Weiner, Brittany A., Elliott, Lisa A., Parrott, Dominic J., Peacock, Chloe M. and Vanman, Eric J. (2013). The psychophysiology of social action: facial electromyographic responses to stigmatized groups predict antidiscrimination action. Basic and Applied Social Psychology, 35 (5), 418-425. doi: 10.1080/01973533.2013.823618
Wallis, Jennifer, Lipp, Ottmar V. and Vanman, Eric J. (2012). Face age and sex modulate the other-race effect in face recognition. Attention, Perception, & Psychophysics, 74 (8), 1712-1721. doi: 10.3758/s13414-012-0359-z
Philipp, Michael C., Storrs, Katherine R. and Vanman, Eric J. (2012). Sociality of facial expressions in immersive virtual environments: A facial EMG study. Biological Psychology, 91 (1), 17-21. doi: 10.1016/j.biopsycho.2012.05.008
Molenberghs, Pascal, Halasz, Veronika, Mattingley, Jason B., Vanman, Eric J. and Cunnington, Ross (2012). Seeing is believing: Neural mechanisms of action-perception are biased by team membership. Human Brain Mapping, 34 (9), 2055-2068. doi: 10.1002/hbm.22044
Vlahou, Christina H., Vanman, Eric J. and Morris, Mary M. (2011). Emotional reactions while watching graphic medical procedures: Vocational differences in the explicit regulation of emotions. Journal of Applied Social Psychology, 41 (11), 2768-2784. doi: 10.1111/j.1559-1816.2011.00839.x
Fanti, Kostas A., Vanman, Eric, Henrich, Christopher C. and Avraamides, Marios N. (2009). Desensitization to Media Violence Over a Short Period of Time. Aggressive Behavior, 35 (2), 179-187. doi: 10.1002/ab.20295
Rani, Pramila, Liu, Changchun, Sarkar, Nilanjan and Vanman, Eric (2006). An empirical study of machine learning techniques for affect recognition in human–robot interaction. Pattern Analysis and Applications, 9 (1), 58-69. doi: 10.1007/s10044-006-0025-y
Vanman,l Eric J., Saltz, Jessica L., Nathan, Laurie R. and Warren, Jennifer A. (2004). Racial Discrimination by Low-Prejudiced Whites : Facial Movements as Implicit Measures of Attitudes Related to Behavior. Psychological Science, 15 (11), 711-714. doi: 10.1111/j.0956-7976.2004.00746.x
Bassett, Jonathan F., Washburn, David A., Vanman, Eric J. and Dabbs, James M. (2004). Assessing the affective Simon paradigm as a measure of individual differences in implicit social cognition about death. Current Research in Social Psychology, 9 (17), 234-246.
Vanman, Eric J., Mejia, Veronica Y., Dawson, Michael E., Schell, Anne M. and Raine, Adrian (2003). Modification of the Startle Reflex in a Community Sample: Do One or Two Dimensions of Psychopathy Underlie Emotional Processing?. Personality and Individual Differences, 35 (8), 2007-2021. doi: 10.1016/S0191-8869(03)00052-7
Vanman, Eric J. (2003). Developing a Comprehensive Social Psychology with Shared Explanations of Primate Social Behavior. International Journal of Comparative Psychology, 16 (1), 33-43.
Striano, Tricia, Brennan, Patricia A. and Vanman, Eric J. (2002). Maternal Depressive Symptoms and 6-Month-Old Infants' Sensitivity to Facial Expressions. Infancy, 3 (1), 115-126. doi: 10.1207/S15327078IN0301_6
Tobin, RM, Graziano, WG, Vanman, EJ and Tassinary, LG (2000). Personality, emotional experience, and efforts to control emotions. Journal of Personality and Social Psychology, 79 (4), 656-669. doi: 10.1037//0022-3514.79.4.656
Vanman, EJ, Dawson, ME and Brennan, PA (1998). Affective reactions in the blink of an eye: Individual differences in subjective experience and physiological responses to emotional stimuli. Personality and Social Psychology Bulletin, 24 (9), 994-1005. doi: 10.1177/0146167298249007
Vanman, Eric J., Paul, Brenda Y., Ito, Tiffany A. and Miller, Norman (1997). The modern face of prejudice and structural features that moderate the effect of cooperation on affect. Journal of Personality and Social Psychology, 73 (5), 941-959. doi: 10.1037/0022-3514.73.5.941
Read, Stephen J., Vanman, Eric J. and Miller, Lynn C. (1997). Connectionism, parallel constraint satisfaction processes, and Gestalt principles: (Re)introducing cognitive dynamics to social psycholog. Personality and Social Psychology Review, 1 (1), 26-53. doi: 10.1207/s15327957pspr0101_3
Vanman, EJ, Boehmelt, AH, Dawson, ME and Schell, AM (1996). The varying time courses of attentional and affective modulation of the startle eyeblink reflex. Psychophysiology, 33 (6), 691-697. doi: 10.1111/j.1469-8986.1996.tb02365.x
Conference Papers
Bartholow, Bruce D., Berntson, Gary G., Bosch, Jos, Burleson, Mary, Hawkley, Louise C., Ito, Tiffany A., Larsen, Jeff T., Norman, Greg J., Norris, Catherine J., Quigley, Karen S., Tassinary, Louis G. and Vanman, Eric (2018). On giving more light than heat: The life and contributions of John T. Cacioppo (1951-2018). 58th Annual Meeting of the Society for Psychophysiological Research, Quebec City Canada, 3-7 October 2018. Hoboken, NJ United States: Wiley-Blackwell.
Grainger, S., Henry, J., Vanman, E., Scott, J. and Labuschagne, I. (2016). Intranasal Oxytocin and Social Perceptual Processing in Late Adulthood. -, -, -. Cary, NC United States: Oxford University Press.
Vanman, Eric J., Johnstone, Kyah and Vartanian, Lenny R. (2014). Compassion (Or the Lack of It) When It Comes to Weight: a Facial Emg Study. 54h Annual Meeting of the Society-for-Psychophysiological-Research, Atlanta Ga, Sep 10-14, 2014. HOBOKEN: WILEY-BLACKWELL.
Vanman, Eric J., Horiguchi, Mari and Sharman, Leah (2013). The social function of tears in crying: a facial electromyographic investigation. 53rd Annual Meeting of the Society for Psychophysiological Research, Florence Italy, 02 - 06 October 2013. Hoboken, NJ United States: Wiley-Blackwell Publishing, Inc.. doi: 10.1111/psyp.12120
Philipp, Michael C., Bernstein, Michael, Vanman, Eric J. and Johnston, Lucy (2012). Adaptive facial mimicry to social exclusion. 52nd Annual Meeting of the Society for Psychophysiological Research, New Orleans La, 19-23 September 2012. Hoboken, NJ United States: Wiley-Blackwell Publishing. doi: 10.1111/j.1469-8986.2012.01440.x
Vanman, Eric J., Horiguchi, Mari, Philipp, Michael and Johnston, Lucy (2012). What is the role of mimicry in detecting posed and genuine smiles?. 52nd Annual Meeting of the Society for Psychophysiological Research, New Orleans La, 19-23 September 2012. Hoboken, NJ United States: Wiley-Blackwell Publishing. doi: 10.1111/j.1469-8986.2012.01437.x
Vanman, EJ, Iyer, A, Henrion, M, Witowski, P, Berndt, SL, Greenaway, KH and Hornsey, MJ (2010). Images of terrorism: The emotional impact of viewing scenes of the aftermath. 50th Annual Meeting of the Society for Psychophysiological Research, Portland, OR, U.S.A., 29 September-3 October, 2010. Malden, MA, U.S.A.: Blackwell Publishing. doi: 10.1111/j.1469-8986.2010.01111.x
Henrion, M. and Vanman, E.J. (2010). Feeling bad about what "we" have done: the p300 as a marker of collective guilt in an intergroup transgression. 50th Annual Meeting of the Society for Psychophysiological Research, Portland, OR, U.S.A., 29 September-3 October, 2010. Malden, MA, U.S.A.: Blackwell Publishing. doi: 10.1111/j.1469-8986.2010.01111.x
Data Collection
McComb, Carly, Vanman, Eric and Tobin, Stephanie (2022). A meta-analysis of the effects of social media exposure on self-evaluations and emotions.. The University of Queensland. (Dataset) doi: 10.48610/2e4fc9f