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Inhibition by ammonium at concentrations above 1000 mgN/L is known to harm the methanogenesis phase of anaerobic digestion. We anaerobically digested swine waste and achieved steady state COD-removal efficiency of around 52% with no fatty-acid or H[subscript 2] accumulation. As the anaerobic microbial community adapted to the gradual increase of total ammonia-N (NH[subscript 3]-N) from 890 ± 295 to 2040 ± 30 mg/L, the Bacterial and Archaeal communities became less diverse. Phylotypes most closely related to hydrogenotrophic Methanoculleus (36.4%) and Methanobrevibacter (11.6%), along with acetoclastic Methanosaeta (29.3%), became the most abundant Archaeal sequences during acclimation. This was accompanied by a sharp increase in the relative abundances of phylotypes most closely related to acetogens and fatty-acid producers (Clostridium, Coprococcus, and Sphaerochaeta) and syntrophic fatty-acid Bacteria (Syntrophomonas, Clostridium, Clostridiaceae species, and Cloacamonaceae species) that have metabolic capabilities for butyrate and propionate fermentation, as well as for reverse acetogenesis. Our results provide evidence countering a prevailing theory that acetoclastic methanogens are selectively inhibited when the total ammonia-N concentration is greater than ~1000 mgN/L. Instead, acetoclastic and hydrogenotrophic methanogens coexisted in the presence of total ammonia-N of ~2000 mgN/L by establishing syntrophic relationships with fatty-acid fermenters, as well as homoacetogens able to carry out forward and reverse acetogenesis.
Syngas fermentation, the bioconversion of CO, CO[subscript 2], and H[subscript 2] to biofuels and chemicals, has undergone considerable optimization for industrial applications. Even more, full-scale plants for ethanol production from syngas fermentation by pure cultures are being built worldwide. The composition of syngas depends on the feedstock gasified and the gasification conditions. However, it remains unclear how different syngas mixtures affect the metabolism of carboxidotrophs, including the ethanol/acetate ratios. In addition, the potential application of mixed cultures in syngas fermentation and their advantages over pure cultures have not been deeply explored. In this work, the effects of CO[subscript 2] and H[subscript 2] on the CO metabolism by pure and mixed cultures were studied and compared. For this, a CO-enriched mixed culture and two isolated carboxidotrophs were grown with different combinations of syngas components (CO, CO:H[subscript 2], CO:CO[subscript 2], or CO:CO[subscript 2]:H[subscript 2]).
Results
The CO metabolism of the mixed culture was somehow affected by the addition of CO[subscript 2] and/or H[subscript 2], but the pure cultures were more sensitive to changes in gas composition than the mixed culture. CO[subscript 2] inhibited CO oxidation by the Pleomorphomonas-like isolate and decreased the ethanol/acetate ratio by the Acetobacterium-like isolate. H[subscript 2] did not inhibit ethanol or H[subscript 2] production by the Acetobacterium and Pleomorphomonas isolates, respectively, but decreased their CO consumption rates. As part of the mixed culture, these isolates, together with other microorganisms, consumed H[subscript 2] and CO[subscript 2] (along with CO) for all conditions tested and at similar CO consumption rates (2.6 ± 0.6 mmol CO L[superscript −1] day[superscript −1]), while maintaining overall function (acetate production). Providing a continuous supply of CO by membrane diffusion caused the mixed culture to switch from acetate to ethanol production, presumably due to the increased supply of electron donor. In parallel with this change in metabolic function, the structure of the microbial community became dominated by Geosporobacter phylotypes, instead of Acetobacterium and Pleomorphomonas phylotypes.
Conclusions
These results provide evidence for the potential of mixed-culture syngas fermentation, since the CO-enriched mixed culture showed high functional redundancy, was resilient to changes in syngas composition, and was capable of producing acetate or ethanol as main products of CO metabolism.
The Journal of Surrealism and the Americas: Vol. 1 No. 1 (2007) - Table of Contents
"Introduction to the Journal" by Samantha Kavky, Claudia Mesch, and Amy H. Winter, p. i-iii.
"Anti-Surrealist Cross-Word Puzzles: Breton, Dalí and Print in Wartime America" by Julia Pine, p. 1-29.
"William Carlos Williams’ A Novelette: an American Counterproposal to French Surrealism" by Céline Mansanti, p. 30-43
"The Vernacular as Vanguard: Alfred Barr, Salvador Dalí, and the U.S. Reception of Surrealism in the 1930s" by Sandra Zalman, p. 44-67
"Ben Cobb, Anarchy and Alchemy: The Films of Alejandro Jodorowsky" by David Church, p. 68-71
"Tamayo: A Modern Icon Reinterpreted" by Marta Julia Clapp, p. 72-76
"Robert Desnos, Surrealism, and 'Poetic Politics'" by Terri J. Gordon, p. 77-80
"Dali and the Specter of Cinema" by Frédérique Camille Joseph-Lowery, p. 81-84
"Julia Kelly's Art, Ethnography and the Life of Objects: Paris, c. 1925-1935" by Susan Power, p. 85-90
"The Janus-faced Legacy of Joseph Beuys" by Tatjana Myoko von Prittwitz, p. 91-93
"A.J. Meek, Clarence John Laughlin: Prophet Without Honor" by Jeffrey Ian Ross, p. 94-98
The Journal of Surrealism and the Americas: Vol. 2 No. 1 (2008) - Table of Contents
“Surrealism and Ethnography: Introduction” by Amy H. Winter, p. i-vi.
“Totemic Landscapes and Vanishing Cultures Through the Eyes of Wolfgang Paalen and Kurt Seligmann” by Marie Mauzé, p. 1-24.
“Surrealist Visions of Pre-Columbian Mesoamerica and the Legacy of Colonialism: the Good, the (Revalued) Bad, and the Ugly” by Keith Jordan, p. 25-63.
“Surrealism and Inuit Art: The Fascination of the Far North” by Florence Duchemin-Pelletier, p. 64-94.
“Bound Objects and Blurry Boundaries: Surrealist Display and (Anti)Nationalism” by Susan Power, p. 95-113.
“Man Ray’s Lost and Found Photographs: Arts of the Americas in Context” by Wendy Grossman, p. 114-139.
“T.J. Demos, The Exiles of Marcel Duchamp” by Bradley Bailey, p. 140-144.
“The Dalí Renaissance: New Perspectives on His Life and Art after 1940 and Danser Gala: L’Art Bouffe de Salvador Dalí” by Mary Ann Caws, p. 145-146.
“Review of ‘The Art of Lee Miller’: Victoria and Albert Museum, 2007” by Peter Barberie, p. 147-151.
“Frida Kahlo in Philadelphia: Life and Death” by Samantha Kavky, p. 152-156.
“Thinking the ‘Post-Indian’: Remix: New Modernities in a Post-Indian World” by Claudia Mesch, p. 157-161.
The Journal of Surrealism and the Americas: Vol. 10 No. 1 (2019) - Table of Contents
“Introduction to the Special Issue on Max Ernst” by Samantha Kavky, p. 1-6.
“Napoleon in the Wilderness: The Transmogrification of a Picture by Max Ernst” by Martin Schieder, p. 7-23.
“Seeing Through an (American) Temperament: Max Ernst’s Microbes, 1946-1953” by Danielle M. Johnson, p. 24-45.
“Max Ernst and the Aesthetic of Commercial Tourism: Max Among Some of His Favorite Dolls” by Carolyn Butler Palmer, p, 46-68.
“Arizona Dream: Maxime Rossi Meets Max Ernst” by Julia Drost, p. 69-83.
“Glowing Like Phosphorus: Dorothea Tanning and the Sedona Western” by Catriona McAra, p. 84-105.
“Conference Review: ‘SURREALISMS: the Inaugural Conference of the International Society for the Study of Surrealism’” by Kristen Strange, p. 106-110.
“Exhibition Review of ‘A Home for Surrealism: Fantastic Painting in Midcentury Chicago’” by Jennifer R. Cohen, p. 111-114.
“Exhibition Review: ‘Native American Art at Documenta 14 and the Issue of Democracy’” by Claudia Mesch, p. 115-120.
The Journal of Surrealism and the Americas: Vol. 7 No. 1 (2013) - Table of Contents
“Introduction to the Issue and Special Section on Native American Surrealisms” by Claudia Mesch, p. i-iv.
“George Morrison’s Surrealism” by W. Jackson Rushing III, p. 1-18.
“César Moro’s Transnational Surrealism” by Michele Greet, p. 19-51.
“A Modernist Moment: Native Art and Surrealism at the University of Oklahoma” by Mark A. White, p. 52-70.
“The Opposite of Snake: Surrealism and the Art of Jimmie Durham” by Mary Modeen, p. 71-95.
“‘My World is Surreal,’ or ‘The Northwest Coast’ is Surreal” by Charlotte Townsend-Gault, p. 96-107.
“Complexity and Contradiction in Native American Surrealism” by Robert Silberman, p. 108-130.
“Review of ‘Double Solitaire: The Surreal Worlds of Kay Sage and Yves Tanguy’ & Kay Sage, ‘The Biographical Chronology and Four Surrealist One Act Plays’” by Larry List, p. 131-134.
The Journal of Surrealism and the Americas: Vol. 6 No. 1 (2012) - Table of Contents
“Notes for a Historiography of Surrealism in America, or the Reinterpretation of the Repressed” by Samantha Kavky, p. i-ix.
“What Makes a Collection Surrealist?: Twentieth-Century Cabinets of Curiosities in Paris and Houston” by Katharine Conley, p. 1-23.
“Dalí, Magritte, and Surrealism’s Legacy, New York c. 1965” by Sandra Zalman, p. 24-38.
“‘What Makes Indians Laugh’: Surrealism, Ritual, and Return in Steven Yazzie and Joseph Beuys” by Claudia Mesch, p. 39-60.
“Cracking up an Alligator: Ethnography, Juan Downey’s Videos, and Irony” by Hjorleifur Jonsson, p. 61-86.
“Review of Effie Rentzou, ‘Littérature Malgré Elle: Le Surréalisme et la Transformation du Littéraire’” by Pierre Taminiaux, p. 87-90.
“In Wonderland: the Surrealist Adventures of Women Artists in Mexico and the United States” by Susan L. Aberth, p. 91-94.