List of Publications

  1. Berman-Frank, I., Zohary, T., Erez, J. and Dubinsky, Z. 1994. CO2 availability, carbonic anhydrase and the annual dinoflagellate bloom in Lake Kinneret. Limnology and Oceanography, 39: 1822-1834.
  2. Zohary, T., Erez, J., Gophen, M., Berman-Frank, I., and Stiller, M. 1994. Seasonality of stable carbon isotopes within Lake Kinneret food web. Limnology and Oceanography, 39: 1030-1043.
  3. Berman-Frank, I., Kaplan, A., Zohary, T. and Dubinsky, Z. 1995. Carbonic anhydrase activity in a natural bloom forming dinoflagellate. Journal of Phycology, 31: 906-913.
  4. Berman-Frank, I. and Erez, J. 1996. Inorganic carbon pools in the bloom forming dinoflagellate Peridinium gatunense. Limnology and Oceanography, 41: 1780-1789.
  5. Berman-Frank, I., Erez J., Zohary, T. and Dubinsky, Z. 1996. Adaptive strategies of phytoplankton to CO2 limitation in nature: The Lake Kinneret case study. Steinberger Y. [Ed.] Preservation of Our World in the Wake of Change. ISEEQS Pubs. 6B: 574 – 576.
  6. Berman-Frank, I., Erez, J. and Kaplan, A. 1998. Changes in inorganic carbon uptake during the progression of a dinoflagellate bloom in a lake ecosystem. Canadian Journal of Botany, 76: 1043-1051.
  7. Vardi, A.†, Berman-Frank, I.†, Rozenberg, T., Hadas, O., Kaplan, A. and Levine, A. 1999. Programmed cell death of the bloom forming dinoflagellate Peridinium gatunense is mediated by CO2 limitation, oxidative stress and a conditioning factor. Current Biology, 9: 1061-1064. (†these authors contributed equally to this work).
  8. Berman-Frank, I. and Dubinsky, Z. 1999. Balanced growth of aquatic plants: myth or reality? BioScience, 49: 29-39.
  9. Dubinsky, Z. and Berman-Frank, I. 2001. Uncoupling primary production from population growth in photosynthesizing organisms in aquatic ecosystems. Aquatic Science, 63: 4-17.
  10. Berman-Frank, I., Cullen, J.T., Shaked, Y., Sherrell, R.M. and Falkowski, P.G. 2001. Iron availability, cellular iron-quotas, and nitrogen fixation in Trichodesmium. Limnology and Oceanography, 46(6): 1249-1260.
  11. Berman-Frank, I., Lundgren, P., Chen, Y., Kupper, H., Kolber, Z., Bergman, B., and Falkowski, P.G. 2001. Segregation of nitrogen fixation and oxygenic photosynthesis in the marine cyanobacterium Trichodesmium. Science, 294: 1534-1537.
  12. Berman-Frank, I., and Falkowski, P.G. 2002. On the evolution of N2 fixation. Science, 295: 799.
  13. Berman-Frank, I., Lundgren P., Falkowski P. 2003. Nitrogen fixation and photosynthetic oxygen evolution in Cyanobacteria. Research Microbiology, 154: 157-164.
  14. Berman-Frank, I., Bidle, K., Haramaty, L. and Falkowski, P. 2004. The demise of the marine cyanobacterium, Trichodesmium spp., via an autocatalyzed cell death pathway. Limnology and Oceanography, 49(4):997-1005.
  15. Küpper, H., Ferimazova, N., Šetlík, I. and Berman-Frank, I. 2004. Traffic lights in Trichodesmium: regulation of photosynthesis for nitrogen fixation studied by chlorophyll fluorescence kinetic microscopy. Plant Physiology, 135: 2120-2133.
  16. Berman-Frank, I. Rosenberg, G., Levitan, O., Haramaty, L., Mari X. 2007. Coupling between autocatalytic cell death and transparent exopolymeric particle production in the marine cyanobacterium Trichodesmium. Environmental Microbiology, 9:1415-1422
  17. Vardi, A., Eisenstadt, D., Murik, O., Berman-Frank, I., Zohary, T., Levine, A. and Kaplan, A. 2007. Synchronization of cell death in a dinoflagellate population is mediated by an excreted thiol protease. Environmental Microbiology, 9: 360–369.
  18. Levitan, O., Rosenberg, G., Setlik, I., Setlikova, E. , Grigel, J., Klepetar, J., Prasil, O. and Berman-Frank, I. 2007. Elevated CO2 enhances nitrogen fixation and growth in the marine cyanobacterium Trichodesmium. Global Change Biology, 13:531-538.
  19. Milligan, A., Berman-Frank, I., Gerchman Y., Dismukes, C., Falkowski P.G. 2007. Light-dependent oxygen consumption in nitrogen-fixing cyanobacteria plays a key role in nitrogenase protection. Journal of Phycology, 43:845-852.
  20. Berman-Frank, I., Quigg, A., Finkel, Z. V., Irwin, A. J., and Haramaty, L. 2007. Nitrogen-fixation strategies and Fe requirements in cyanobacteria. Limnology and Oceanography, 52:2260-2269.
  21. Man-Aharonovich, D., Kress, N., Bar Zeev, E., Berman-Frank, I., and Beja, O. 2007. Molecular ecology of nifH genes and transcripts in the eastern Mediterranean Sea. Environmental Microbiology, 9:2354-2363.
  22. Küpper, H. Seibert, S., Šetlík, I., Prášil, O., Šetlikova, E., Lohscheider, J., Levitan, O., Strittmatter, M., Adamska, I., and Berman-Frank, I. 2008. Iron Limitation in Trichodesmium reveals new insights into regulation of photosynthesis for N-fixation. New Phytologist, 179:784-798.
  23. Bar Zeev, E., Yogev, T., Man-Aharonovich, D., Kress, N., Herut, B., Béjà, O. and Berman-Frank, I. 2008. Seasonal dynamics of the endosymbiotic, nitrogen-fixing cyanobacterium Richelia intracellularis in the Eastern Mediterranean Sea. The ISME Journal, 2: 911-923.
  24. Berman-Frank, I., Chen, Yi-bu, Gao, Y., Fennel, K., Follows, M., Milligan, A., and Falkowski P.G. 2008. Feedbacks Between the Nitrogen, Carbon and Oxygen Cycles. Capone, DG, D Bronk, M Mulholland and EJ Carpenter, Eds. Nitrogen in the Marine Environment, 2nd edition. San Diego, Academic Press/ Elsevier ISBN 9780123725226.
  25. Bar-Zeev, E., Berman-Frank I., Liberman, B., Rahav, E., Passow, U., and Berman,T. 2009. Transparent exopolymer particles: potential agents for organic fouling and biofilm formation in desalination and water treatment plants. Desalination and Water Treatment, 3:136-142.
  26. Berman-Frank, I. and Berman, T. 2009. Introduction to primary production in seagrasses and macroalgae: closing the GAP between concepts and measurements. Aquatic Botany,7: 125-126
  27. Berman-Frank I, Berman T., MacIntyre H. 2009. (Coeditors AME special volume on GAP workshop) Progress and perspectives in aquatic primary productivity: introduction. Aquatic Microbial Ecology, 56: 109–111
  28. Bar-Zeev E., Berman-Frank I, Stambler, N., Vázquez Domínguez, E., Zohary, T., Capuzzo,E., Meeder, E., Suggett, D.J., Iluz, D., Dishon, G., and Berman, T. 2009. Transparent Exopolymer Particles (TEP) link phytoplankton and bacterial production in the Gulf of Aqaba. Aquatic Microbial Ecology, 56:217-225
  29. Suggett, D.J., Stambler, N., Prášil, O., Kolber, Z., Quigg, A., Vázquez-Dominguez,E., Zohary,T., Berman, T., Iluz, D, Levitan, O., Lawson,T., Meeder, E., Bar-Zeev, E., Medova, H., and Berman-Frank, I. 2009. Nitrogen and phosphrous limitation of oceanic microbial growth during spring in the Gulf of Aqaba. Aquatic Microbial Ecology, 56:227-239
  30. Kelman, D., Ben-Amotz, A., and Berman-Frank, I. 2009. Carotenoids provide the major antioxidant defense in the globally significant N2 fixing marine cyanobacterium Trichodesmium . Environmental Microbiology, 11(7): 1897-1908
  31. Tzahor, S., Man-Aharonovich, D., Kirkup, B.C., Yogev, T., Berman-Frank, I., Polz, M.F., Beja, O., and Mandel-Gutfreund, Y. 2009. A supervised learning approach for taxonomic classification of core-photosystem-II genes and transcripts in the marine environment. BMC Genomics, doi:10.1186/1471-2164-10-229. 10:229
  32. Ionescu, D., Oren, A., Levitan, O., Hindiyeh, M., Malkawi H., and Berman-Frank, I. 2009. The cyanobacterial community of the Zerka Ma’in hot springs, Jordan: morphological and molecular diversity and nitrogen fixation. Algological Studies, 130: 109 – 124
  33. Man-Aharonovich, D., Philosof, A., Kirkup, B.C., Le Gall, F., Yogev, T., Berman-Frank, I., Polz, M.F., Vaulot, D., and Béjà, O. 2010 Diversity of active marine picoeukaryotes in the eastern Mediterranean Sea unveiled using photosystem-II psbA transcripts. The ISME Journal, 4(8):1044-52.
  34. Levitan, O., Brown, C.M., Sudhaus, S., Campbell, D., LaRoche, J., and Berman-Frank, I. 2010. Regulation of Nitrogen Metabolism in the Marine Diazotroph Trichodesmium IMS101 under Varying Temperatures and Atmospheric CO2 Concentrations. Environmental Microbiology, 12(7):1899-1912.
  35. Levitan, O., Kranz, S., Spungin, D., Prasil, O., Rost, B., and Berman-Frank, I. 2010. The combined effects of pCO2 and light on the N2 fixing cyan bacterium Trichodesmium IMS101: A mechanistic view. Plant Physiology, 154. 10.1104/pp.110.159285
  36. Kranz, S., Levitan, O., Prasil, O., Richter, K.-U., Berman-Frank, I., and Rost, B. 2010. Combined effects of pCO2 and light on the N2 fixing cyanobacteria Trichodesmium IMS101: Physiological responses. Plant Physiology, 154. 10.1104/pp.110.159145
  37. Rachamim, T., Stambler, N., Zohary, T., Berman-Frank, I., and Gal, G. 2010. Zooplankton contribution to the particulate N and P in Lake Kinneret, Israel, under changing water levels. Hydrobiologia, 655:121–135
  38. Sharon, Y., Levitan, O., Spungin, D., Berman-Frank, I. and Beer, S. 2011 Photoacclimations of the seagrass Halophila stipulacea to the dim irradiance at its 50 m depth limit. Limnology and Oceanography, 56(1): 357–362.
  39. Levitan, O., Sudhaus, S., LaRoche, J., and Berman-Frank I. 2010. The influence of varying pCO2 and temperature on gene expression of carbon and nitrogen pathways in Trichodesmium IMS101. PLoS One, 5(12): e15104. doi:10.1371
  40. Yogev, T., Rahav, E., Bar-Zeev, E., Aharonovich, D., Stambler, N., Kress, N., Beja, O., Mulholland, M., Herut, B., and Berman-Frank, I. 2011. Is dinitrogen fixation significant in the Levantine basin- eastern Mediterranean Sea? Environmental Microbiology, 13(4), 854–871.
  41. Bar-Zeev, E., Berman, T., Rahav, E., Dishon, G., Herut, B., Kress, N., and Berman-Frank, I. 2011. Transparent exopolymer particle (TEP) dynamics in the eastern Mediterranean Sea. Marine Ecology Progress Series, 431:107-118
  42. Rubin, M., Berman-Frank, I., and Shaked, Y. 2011. Dust- and mineral-iron utilization by the marine dinitorgen-fixer Trichodesmium. Nature Geosciences, 4:529–534
  43. Berman-Frank, I. and Rahav, E. 2012 Nitrogen fixation as a source for new production in the Mediterranean Sea: a review. In N. Stambler (Ed.). Life in the Mediterranean Sea. Nova Science Publishers. NY, Ch. 8, 199-226.
  44. Bar-Zeev, E., Belkin, N., Liberman, B., Berman, T., and Berman-Frank, I. 2012. Rapid sand filtration pretreatment for SWRO: Microbial maturation dynamics and filtration efficiency of organic matter. Desalination, 286: 120-130
  45. Belkin, N., Bar-Zeev, E., Berman, T., and Berman-Frank, I. 2012. Two innovative devices for depth sampling in granular filtration systems. Desalination, 286: 115-119.
  46. Bar-Zeev, E., Berman-Frank, I., Girshevitz, O., and Berman, T. 2012. Revised paradigm of aquatic biofilm formation facilitated by microgel transparent exopolymer particles. PNAS, 109: 9119-9124
  47. Moore, C.M., Mills, M.M., Arrigo, K.R., Berman-Frank, I., Bopp, L., Boyd, P.W., Galbraith, E.D., Geider, R.J., Guieu, C., Jaccard, S.L., Jickells, T.D., La Roche, J., Lenton, T.M., Mahowald, N.M., Marañón, E., Marinov, I., Moore, J.K., Nakatsuka, T., Oschlies, A., Saito, M.A., Thingstad, T.F., Tsuda, A., and Ulloa, O. 2013. Processes and patterns of oceanic nutrient limitation. Nature Geoscience, 6: 701-710
  48. Sorek, M., Yacobi, Y.Z., Roopin, M., Berman-Frank, I., and Levi, O. 2013. Photosynthetic circadian rhythmicity patterns of Symbiodium, the coral endosymbiotic algae. Proceedings of the Royal Society B-Biological Sciences, 280:
  49. Bar-Zeev, E., Belkin, N., Liberman, B., Berman-Frank, I., and Berman, T. 2013. Bioflocculation: Chemical free, pre-treatment technology for the desalination industry. Water Research, 47:3093-3102.
  50. Rahav, E., Herut, B., Stambler, N., Bar-Zeev, E., Mulholland, R.M., and Berman-Frank, I. 2013. Uncoupling between dinitrogen fixation and primary productivity in the Eastern Mediterranean Sea. JGR Biogeosciences, 18:195-202
  51. Rahav, E., Herut, B., Levi, A., Mulholland, R.M. and Berman-Frank, I. 2013. Springtime contribution of dinitrogen fixation to primary production across the Mediterranean. Ocean Sciences, 9: 1-10, doi: 10.5194/os-9-1-2013.
  52. Bar-Zeev, E., Avishay I., Bidle K.D., and Berman-Frank I. 2013. Programmed cell death in the marine cyanobacterium Trichodesmium mediates carbon and nitrogen export. The ISME Journal, 7:2340-2348
  53. Rahav, E., Bar-Zeev, E., Ohayon, S., Elifantz, H., Belkin, N., Herut, B., Mulholland, M.R. and Berman-Frank, I. 2013 Dinitrogen fixation in aphotic oxygenated marine environments. Frontiers in Microbiology, 4:227. doi: 10.3389/fmicb.2013.00227
  54. Krom, M., Kress, N., Berman-Frank, I., and Rahav, E. 2013. Past, present and future patterns in the nutrient chemistry of the Eastern Mediterranean. In Goffredo, S. and Dubinsky, Z. (ed.) The Mediterranean Sea: Its history and present challenges.  Springer, New-York. pp. 49-68                                                                                                                                    
  55. Pfreundt, U., Kopf, M., Belkin, N., Berman-Frank, I., Hess, W.R. 2014. The primary transcriptome of the marine diazotroph Trichodesmium erythraeum IMS101. Scientific Reports, 4: 6187                                                                          
  56. Spungin, D., Berman-Frank, I., and Levitan, O. 2014. Trichodesmium‘s strategies to alleviate phosphorus limitation in the future acidified oceans. Environmental Microbiology, 16: 1935-1947                                              
  57. Pfreundt, U., Miller, D., Adudumilli, L., Stambler, N., Berman-Frank, I., and Hess, W.R. 2014. Depth dependent metatranscriptomes of the marine pico-/nanoplanktonic communities in the Gulf of Aqaba/Eilat during seasonal deep mixing. Marine Genomics, 18(B): 93-95
  58. Rahav, E., Herut, B., Mulholland, M.R., Belkin, N., Elifantz, H. and Berman-Frank, I. 2015. Hetrotrophic and autotrophic contribution to dinitrogen fixation in the Gulf of Aqaba. Marine Ecology Progress Series, 522: 67-77
  59. Dutkiewicz, S., Morris, J.J., Follows, M.J., Scott, J., Levitan, O., Dyhrman, S.T., and Berman-Frank, I. 2015. Impact of ocean acidification on the structure of future phytoplankton communities. Nature Climate Change, DOI: 10.1038/NCLIMATE2722
  60. Belkin, N., Rahav, E., Elifantz, H., Kress, N., and Berman-Frank, I. 2015. Enhanced salinities, as a proxy of seawater desalination discharges, impact coastal microbial communities of the eastern Mediterranean Sea. Environmental Microbiology, DOI: 10.1111/1462-2920.12979
  61. Levi, A., Bar-Zeev, E., Elifantz, H., Berman, T., and Berman-Frank, I. 2016. Characterization of microbial communities in water and biofilms along a large scale SWRO desalination facility: Site-specific prerequisite for biofouling treatments. Desalination, 378: 44-52                                                                                                                                          
  62. Bonnet, S., Berthelot, H., Turk-Kubo, K., Fawcett, S., Rahav, E., L’Helguen, S., and Berman-Frank, I. 2016. Dynamics of N-2 fixation and fate of diazotroph-derived nitrogen in a low-nutrient, low-chlorophyll ecosystem: results from the VAHINE mesocosm experiment (New Caledonia). BIOGEOSCIENCES, 13: 2653-2673                                  
  63. Berman-Frank, I., Spungin, D., Rahav, E., Van Wambeke, F., Turk-Kubo, K.,and Moutin, T. 2016. Dynamics of transparent exopolymer particles (TEP) during the VAHINE mesocosm experiment in the New Caledonian lagoon. BIOGEOSCIENCES, 13: 3793-3805                                                                                                                                                            
  64. Benavides, M., Bonnet, S., Hernandez, N., Maria Martinez-Perez, A., Nieto-Cid, M., Anton Alvarez-Salgado, X., Banos, I., Montero, M.F., Mazuecos, I.P., Gasol, J.M., Osterholz, H., Dittmar, T., Berman-Frank, I., and Aristegui, J. 2016. Basin-wide N-2 fixation in the deep waters of the Mediterranean Sea. Global Biogeochemical Cycles, 30: 952-961                       
  65. Spungin, D., Pfreundt, U., Berthelot, H., Bonnet, S., AlRoumi, D., Natale, Frank., Hess, W.R., Bidle, K.D., and Berman-Frank, I. 2016. Mechanisms of Trichodesmium demise within the New Caledonian lagoon during the VAHINE mesocosm experiment. BIOGEOSCIENCES, 13: 4187-4203                                                                                                                  
  66. Pfreundt, U., Spungin, D., Bonnet, S., Berman-Frank, I., and Hess, W.R. 2016. Global analysis of gene expression dynamics within the marine microbial community during the VAHINE mesocosm experiment in the southwest Pacific. BIOGEOSCIENCES, 13: 4135-4149                                                                                                                                                
  67. Bonnet, S., Baklouti, M., Gimenez, A., Berthelot, H., and Berman-Frank, I. 2016. Biogeochemical and biological impacts of diazotroph blooms in a low-nutrient, low-chlorophyll ecosystem: synthesis from the VAHINE mesocosm experiment (New Caledonia). BIOGEOSCIENCES, 13: 4461-4479                                                                                   
  68. Bonnet, S., Berthelot, H., Turk-Kubo, K., Cornet-Barthaux, V., Fawcett, S., Berman-Frank, I., Barani, A., Gregori, G., Dekaezemacker, J., Benavides, M., and Capone, D.G. 2016. Diazotroph derived nitrogen supports diatom growth in the South West Pacific: A quantitative study using nanoSIMS. Limnology and Oceanography, 61: 1549-1562           
  69. Benavides, M., Bonnet, S., Hernandez, N., Maria Martinez-Perez, A., Nieto-Cid, M., Anton Alvarez-Salgado, X., Banos, I., Montero, M.F., Mazuecos, I.P., Gasol, J.M., Osterholz, H., Dittmar, T., Berman-Frank, I., and Aristegui, J. 2016. Basin-wide N-2 fixation in the deep waters of the Mediterranean Sea. Global Biogeochemical Cycles, 30: 952-961
  70. Krom, M.D., Shi, Z., Stockdale, A. , Berman-Frank, I., Giannakourou, A., Herut, B., Lagaria, A., Papageorgiou, N., Pitta, P., Psarra, S., Rahav, E., Scoullos, M.,  Stathopoulou, E., Tsiola A., and Tsagaraki, T.M. 2016. Response of the Eastern Mediterranean Microbial Ecosystem to Dust and Dust Affected by Acid Processing in the Atmosphere. Frontiers in Marine Science doi: 10.3389/fmars.2016.00133                                                                                                                                       
  71. Rahav, E., Shun-Yan,  C.,  Cui, G., Liu, H., Tsagaraki, T. M., Giannakourou, A., Tsiola, A., Psarra, S., Lagaria, A., Mulholland, M. R., Stathopoulou, E., Paraskevi, P., Herut, B., and Berman-Frank I. 2016. Evaluating the Impact of Atmospheric Depositions on Springtime Dinitrogen Fixation in the Cretan Sea (Eastern Mediterranean)—A Mesocosm Approach. Frontiers in Marine Science, 10.3389/fmars.2016.00180                                                                                                                
  72. Guo, C., Xia, X., Pitts, P., Herut, B., Rahave, E., Berman-Frank, I., Giannakourou, A., Tsiola, A., Tsagaraki, T., and Liu, H. 2016. Shifts in microbial community structure and activity in the ultra-oligotrophic Eastern Mediterranean Sea driven by Saharan Dust and European aerosol deposition. Frontiers in Marine Science,                                                                         
  73. Hou, S., Pfreundt, U., Miller, D., Berman-Frank, I., and Hess. W.R. Accepted. mdRNA-Seq analysis of marine microbial communities. Scientific Reports,                                                                                                                     
  74. Herut, B., Rahav, E., Tsagaraki, T.M., Giannakourou, A., Tsiola, A., Psarra, S., Lagaria, A., Papageorgiou, N., Mihalopoulos, N., Theodosi, C.N., Violaki, K., Stathopoulou, E., Scoullos, M., Krom, M.D., Stockdale, A., Shi, Z., Berman-Frank, I., Meador, T.B., Tanaka, T., and Paraskevi, P. 2016. The Potential Impact of Saharan Dust and Polluted Aerosols on Microbial Populations in the East Mediterranean Sea, an Overview of a Mesocosm Experimental Approach. Frontiers in Marine Science, doi: 10.3389/fmars.2016.00226                                                                                                                                         
  75. Natalia Belkin, Eyal Rahav , Hila Elifantz , Nurit Kress , Ilana Berman-Frank. (2017) The effect of coagulants and antiscalants discharged with seawater desalination brines on coastal microbial communities: a laboratory and in situ study from the 3 southeastern Mediterranean. Water Research. 110, pp.321-331.
  76. Miller D., Pfreundt U., Hou S., Lott S. C., Hess W.R., Berman-Frank I. (2017) Microbial metatranscriptomes from the thermally stratified Gulf of Aqaba/Eilat during summer. Marine genomics. 32, pp.23-26.
  77. Ulrike Pfreundt*, Dina Spungin*, Shengwei Hou, Björn Voss, Ilana Berman-Frank,Wolfgang R. Hess. (2017) Genome of a giant bacteriophage from a decaying Trichodesmium Marine Genomics 33:21-25 (*equal contribution).
  78. Tsagaraki TM, Herut B, Rahav E, Berman Frank IR, Tsiola A, Tsapakis M, Giannakourou A, Gogou A, Panagiotopoulos C, Violaki K, Psarra S, Lagaria A, Christou ED, Papageorgiou N, Zervoudaki S, Puelles MLFd, Nikolioudakis N, Meador TB, Tanaka T, Pedrotti ML, Krom MD and Pitta P (2017) Atmospheric Deposition Effects on Plankton Communities in the Eastern Mediterranean: A Mesocosm Experimental Approach.  Mar. Sci.4:210. doi: 10.3389/fmars.2017.00210
  79. Moisander PH, Benavides M, Bonnet S, Berman-Frank I, White AE and Riemann L (2017) Chasing after Non-cyanobacterial Nitrogen Fixation in Marine Pelagic Environments.  Microbiol. 8:1736. doi: 10.3389/fmicb.2017.01736
  80. Miller D., Pfreundt U., Hou S., Lott S. C., Hess W.R., Berman-Frank I. (2017) Winter Mixing Induces Reshuffling and Impacts Gene Expression of Marine Microbial Populations in the Gulf of Aqaba. Aquatic Microbial Ecology. 80:223-242.