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15 results on '"MacLean, C"'

1. A Perfect Storm Averted: Flawed Systems, a Dropped Ball, and Cognitive Biases Delay a Critical Diagnosis

Author

Thomas J. Roberts, Maclean C. Sellars, Jacob M. Sands, and Joseph O. Jacobson

Subjects
Cognition, Oncology, Oncology (nursing), Neoplasms, Health Policy, Teaching Rounds, Humans, Female, Morbidity, Middle Aged, Quality Improvement
Abstract

This is the first case of Cancer Morbidity, Mortality, and Improvement Rounds, a series of articles intended to explore the unique safety risks experienced by oncology patients through the lens of quality improvement, systems and human factors engineering, and cognitive psychology. This case highlights how multiple overlapping factors contributed to a delay in diagnosing disseminated tuberculosis in a patient with lung cancer. The discussion focuses on the ways that cognitive biases contributed to the delayed diagnosis in a patient who, with the benefit of hindsight, exhibited several signs and symptoms suggesting tuberculosis. Cancer Morbidity, Mortality, and Improvement Rounds is a series of articles intended to explore the unique safety risks experienced by oncology patients through the lens of quality improvement, systems and human factors engineering, and cognitive psychology. For purposes of clarity, each case focuses on a single theme, although, as is true for all medical incidents, there are almost always multiple, overlapping, contributing factors. The quality improvement paradigm used here, which focuses on root cause analyses and opportunities to improve care delivery systems, was previously outlined in this journal. 1

Published
2022
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2. Cancer vaccines: Building a bridge over troubled waters

Author

MacLean C. Sellars, Catherine J. Wu, and Edward F. Fritsch

Subjects
Mice, Vaccines, Immune System, Neoplasms, Vaccination, Animals, Humans, Cancer Vaccines, General Biochemistry, Genetics and Molecular Biology, Immunity, Innate
Abstract

Cancer vaccines aim to direct the immune system to eradicate cancer cells. Here we review the essential immunologic concepts underpinning natural immunity and highlight the multiple unique challenges faced by vaccines targeting cancer. Recent technological advances in mass spectrometry, neoantigen prediction, genetically and pharmacologically engineered mouse models, and single-cell omics have revealed new biology, which can help to bridge this divide. We particularly focus on translationally relevant aspects, such as antigen selection and delivery and the monitoring of human post-vaccination responses, and encourage more aggressive exploration of novel approaches.

Published
2022

3. Hydroxycarbamide plus Aspirin vs Aspirin alone in patients with essential Thrombocythaemia aged 40-59 years without high-risk features

Author

Buck, G, Godfrey, A, Campbell, P, MacLean, C, Cook, J, Temple, J, Wilkins, B, Wheatley, K, Nangalia, J, Grinfeld, J, McMullin, M, Forsyth, C, Kiladjian, J, Green, A, and Harrison, C

Subjects
SDG 3 - Good Health and Well-being
Abstract

Purpose: Cytoreductive therapy is beneficial in patients with essential thrombocythemia at high risk of thrombosis. However its value in those lacking high-risk features remains unknown. This open-label, randomized trial compared hydroxycarbamide plus aspirin with aspirin alone in patients with ET aged 40- 59 and without high-risk factors or extreme thrombocytosis. Methods: Patients were aged 40-59 years and lacked a history of ischemia, thrombosis, embolism, hemorrhage, extreme thrombocytosis (≥1500x109 /L), or hypertension or diabetes requiring therapy. 382 patients were randomized 1:1 to hydroxycarbamide plus aspirin or aspirin alone. The composite primary endpoint was time to arterial or venous thrombosis, serious hemorrhage or death from vascular causes. Secondary endpoints were time to first arterial or venous thrombosis, first serious hemorrhage, death, incidence of transformation and patient-reported quality of life. Results: After a median follow-up of 73 months and a total follow-up of 2373 patient years there was no significant difference between the arms in the likelihood of patients reaching the primary endpoint (hazard ratio 0.98, 95% CI 0.42-2.25, P=1.0). The incidence of significant vascular events was low, at 0.93 per 100 patient-years (95% CI 0.61-1.41). There were also no differences in overall 4 survival, in the composite endpoint of transformation to myelofibrosis, acute myeloid leukaemia or myelodysplasia, in adverse events or in patient-reported quality of life. Conclusions: In ET patients aged 40-59 and lacking high-risk factors for thrombosis or extreme thrombocytosis, pre-emptive addition of hydroxycarbamide to aspirin did not reduce vascular events, myelofibrotic or leukemic transformation. Patients aged 40-59 without other clinical indications for treatment (such as previous thrombosis or haemorrhage), who have a platelet count less than 1500x109 /L, should not receive cytoreductive therapy.

Published
2018
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4. 775 Immune Checkpoint Inhibitor Therapy in Patients With Preexisting Inflammatory Bowel Disease

Author

Jiajia Zhang, MacLean C. Sellers, Justine V. Cohen, Ibraheim Hajir, Nick Powell, Lisa Manuzzi, David Faleck, Gal Merkel, Hamzah Abu-Sbeih, David J. Pinato, Christina A. Arnold, Guy Ben-Betzalel, Yinghong Wang, Sai-Ching Yeung, Douglas B. Johnson, Giulia Costanza Leonardi, Aanika Balaji, Sarah A. Weiss, Michael Dougan, Mark F. Lythgoe, Abdul Rafeh Naqash, Jarushka Naidoo, Dwight H. Owen, Robin B. Mendelsohn, Elad Sharon, Mark M. Awad, Giuseppe Lamberti, and Biagio Ricciuti

Subjects
Hepatology, business.industry, Immune checkpoint inhibitors, Immunology, Gastroenterology, medicine, In patient, medicine.disease, business, Inflammatory bowel disease
Published
2019
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6. Computer simulated cost effectiveness of care management strategies on reduction of long-term sequelae in patients with non-insulin dependent diabetes mellitus

Author

Demers D, Clark N, Benedini K, Nagy P, Farnham P, Plant-DeHayes A, MacLean C, and Tolzmann G

Subjects
Blood Glucose, medicine.medical_specialty, Health (social science), Cost Control, Leadership and Management, Cost effectiveness, media_common.quotation_subject, Cost-Benefit Analysis, Disease, Patient Care Planning, MicroWorlds, Diabetes mellitus, Outcome Assessment, Health Care, medicine, Humans, In patient, Computer Simulation, Business case, Intensive care medicine, Care Planning, computer.programming_language, media_common, business.industry, Delivery of Health Care, Integrated, Health Policy, Non insulin dependent diabetes mellitus, Disease Management, medicine.disease, Payment, Diabetes Mellitus, Type 2, Medical emergency, business, computer, Models, Econometric, Vermont
Abstract

Systems dynamics and computer "microworlds" offer a window on the long-term benefit of investing in aggressive care management for patients with non-insulin dependent diabetes mellitus. This article describes how clinicians, planners, payment specialists, and patients collaborated to make the business case for aggressive management of this disease.

Published
1998

7. Hepatitis B and C infection in an institution for the developmentally handicapped

Author

Perry E, Hicks F, Morbey M, Chaudhary Rk, and MacLean C

Subjects
Pediatrics, medicine.medical_specialty, Down syndrome, business.industry, Institutionalization, General Medicine, Hepatitis C, Hepatitis B, medicine.disease, Epidural space, medicine.anatomical_structure, Spinal cord compression, Intellectual Disability, Immunology, medicine, Humans, Down Syndrome, business, Spinal Neoplasms
Published
1992

9. The long poem (epic, romance, etc.) in English, from Spenser to Glover, both included

Author

MacLean, C. M.

Subjects
Annexe Thesis Digitisation Project 2019 Block 22
Abstract

Chapter I. The Long Poem. • II. The Faerie Queene. • III. Translations of the 16th Century. • IV. Historical Poems of the 16th Century. • V. Allegorists of the 17th Century and the Pastoral work of Browne. • VI. Later Allegorists of the 17th Century. • VII. Heroic Romances (mostly Caroline). • VIII. Milton. • IX. Long Poem in the later 17th Century - Cowley - Dryden. • X. The Mock-Heroic - Butler - Garth - Prior - Pope. • XI. Blackmore (early epic of 18th century). • XII. Long Poem in Couplet of 18th. Century - Prior - Gay - Parnell - Pope . . . . Falconer. • XIII. Long Poem of Reactionists. • XIV. Glover and late 18th century epic. • XV. Review of subject.

Published
1913

10. Additional support for schizophrenia linkage on chromosomes 6 and 8: A multicenter study

Author

Levinson, D. F., Wildenauer, D. B., Schwab, S. G., Albus, M., Hallmayer, J., Lerer, B., Maier, W., Blackwood, D., Muir, W., Stclair, D., Morris, S., Moises, H. W., Yang, L., Kristbjarnarson, H., Helgason, T., Wiese, C., Collier, D. A., Holmans, P., Daniels, J., Mark Rees, Asherson, P., Roberts, Q., Cardno, A., Arranz, M. J., Vallada, H., Mcguffin, D., Owen, M. J., Pulver, A. E., Antonarakis, S. E., Babb, R., Blouin, J. L., Demarchi, N., Dombroski, B., Housman, D., Karayiorgou, M., Ott, J., Kasch, L., Kazazian, H., Lasseter, V. K., Loetscher, E., Luebbert, H., Nestadt, G., Ton, C., Wolyniec, P. S., Laurent, C., Dechaldee, M., Thibaut, F., Jay, M., Samolyk, D., Petit, M., Campion, D., Mallet, J., Straub, R. E., Maclean, C. J., Easter, S. M., Oneill, F. A., Walsh, D., Kendler, K. S., Gejman, P. V., Cao, Q. H., Gershon, E., Badner, J., Beshah, E., Zhang, J., Riley, B. P., Rajagopalan, S., Mogudicarter, M., Jenkins, T., Williamson, R., Delisi, L. E., Garner, C., Kelly, M., Leduc, C., Cardon, L., Lichter, J., Harris, T., Loftus, J., Shields, G., Comasi, M., Vita, A., Smith, A., Dann, J., Joslyn, G., Gurling, H., Kalsi, G., Brynjolfsson, J., Curtis, D., Sigmundsson, T., Butler, R., Read, T., Murphy, P., Chen, A. C. H., Petursson, H., Byerley, B., Hoff, M., Holik, J., Coon, H., Nancarrow, D. J., Crowe, R. R., Andreasen, N., Silverman, J. M., Mohs, R. C., Siever, L. J., Endicott, J., Sharpe, L., Walters, M. K., Lennon, D. P., Hayward, N. K., Sandkuijl, L. A., Mowry, B. J., Aschauer, H. N., Meszaros, K., Lenzinger, E., Fuchs, K., Heiden, A. M., Kruglyak, L., Daly, M. J., and Matise, T. C.

11. The HOPE (Heart Outcomes Prevention Evaluation) Study: The design of a large, simple randomized trial of an angiotensin converting enzyme inhibitor (ramipril) and vitamin E in patients at high risk of cardiovascular events

Author

Mindlen, F., Nordaby, R., Ruiz, M., Zavala, A., Guzman, L., Martinez, F., Diaz, Rr, Mackey, C., Marino, M., Romero, G., Zapata, G., Cuneo, C., Kawamura, T., Coelho, O., Massayochi, O., Braga, J., Labrunie, A., Bodanese, L., Manenti, E., Vitola, D., Nicolau, J., Amodeo, C., Armaganijan, D., Bertolami, M., Caramelli, B., Carvalho, A., Cirenza, C., Fichino, M., Franken, R., Ghorayeb, N., Kadri, T., Leao, P., Malheiros, F., Pavanello, R., Ramires, F., Ramires, J., Savioli, F., Sousa, A., Tanajura, L., Topps, D., Korner, L., Martinez, V., Baptie, B., Basinger, M., Baylis, B., Beresford, P., Edwards, A., Giannaccaro, P., Groenewoud, Y., Grose, M., Kellen, J., Lam, S., Lesoway, R., Ma, P., Meldrum, D., Mitchell, D., Mitchell, Lb, Roth, D., Shumak, S., Simon, M., Stone, J., Warnica, W., Wyse, D., Neffgen, C., Neffgen, J., Armstrong, F., Armstrong, W., Bell, N., Black, W., Brass, N., Brenneis, F., Brownoff, R., Chaytors, G., Debanne, D., Derksen, C., Donoff, M., Dzavik, V., Goeres, M., Greenwood, P., Gulamhusein, S., Hui, W., Hutchison, K., Kasian, L., Kasza, L., Krikke, E., Kvill, L., Lakhani, Z., Linklater, D., Mackel, J., Martin, S., Montague, T., Moores, D., Musseau, A., Muzyka, T., Paradis, J., Prosser, A., Ryan, E., Senaratne, M., Stenerson, P., Talibi, T., Teo, K., Young, C., Zuk, V., White, R., Browne, K., Browne, M., Happel, K., Irving, A., Plesko, A., Donnelly, R., Radomsky, N., Felker, P., Larsen, D., Morse, J., Rowntree, C., Thompson, J., Wedel, R., Bloomberg, G., Chomin, G., Dahl, M., Leong, W., Moy, V., Heath, J., Marshall, J., Terwiel, M., Kenefick, G., Kuritzky, R., Stevens, K., Weddings, K., Barban, K., Imrie, J., Woo, K., Ashton, T., Calvert, K., Bishop, W., Sweeney, R., Breakwell, L., Kornder, J., Pearce, S., Polasek, P., Richardson, P., Ghosh, S., Rielly, M., Wagner, K., Bemstein, V., Dawson, K., Lee, P., Lewis, J., Macdonald, K., Mcgee, L., Thompson, C., Hilton, D., Illott, K., Klinke, P., Mcconnell, J., Rabkin, S., Ong, A., Ong, G., Bedard, D., Hoeschen, R., Mehta, P., Mohammad, I., Morris, A., Bessoudo, R., Dobbins, N., Mclellan, L., Milton, J., Davis, R., Okeefe, D., Smith, R., Joyce, C., Parsons, M., Skanes, J., Sussex, B., Tobini, M., Ravalia, M., Sherman, G., Worrall, G., Atkinson, A., Hatheway, R., Johnson, B., Barnhill, S., Bata, I., Cosseet, J., Johnstone, D., Macfarlane, M., Sheridan, W., Crossman, L., Folkins, D., Shirley, M., Machel, T., Morash, J., Gupta, M., Mayich, M., Vakani, T., Baitz, T., Macphee, E., Turton, E., Turton, M., Chan, N., Misterski, J., Raco, D., Curnew, G., Fallen, E., Finkelstein, L., Gerstein, H., Hardman, P., Lawand, S., Lonn, E., Magi, W., Mcqueen, M., Panju, A., Patterson, R., Sullivan, B., Sullivan, H., Sullivan, M., Taylor, K., Worron, I., Yusuf, S., Cameron, W., Noseworthy, C., Houlden, R., Lavalle, T., Fowlis, R., Janzen, I., Arnold, M., Cann, M., Carroll, S., Dumaresq, S., Edmonds, M., Furlong, P., Geddes, C., Graham, E., Harris, K., Hramiak, I., Kennedy, R., Kostuk, W., Krupa, M., Lent, B., Lovell, M., Maclean, C., Massel, D., Mcmanus, R., Mcsherry, J., Munoz, C., Occhipinti, J., Oosterveld, L., Pflugfelder, P., Powers, S., Southern, R., Spence, D., Squires, P., Wetmore, S., Willing, J., Wisenberg, G., Wolfe, B., Kannampuzha, P., Rebane, T., Sluzar, V., Hess, A., Chan, Y., Thomson, D., Baigrie, R., Dubbin, J., Liuni, C., Tan, Kw, Brankston, E., Hewson, P., Hrycyshyn, B., Kapusta, W., Knox, L., Lockner, C., Whitsitt, P., Baird, M., Conroy, D., Davies, Ra, Davies, Rf, Fraser, M., Hagar, S., Hierlihy, P., Keely, E., Khan, S., Lau, Dgw, Marois, L., Nemeth, K., Reeves, E., Turek, M., Vexler, R., Young, D., Kumar, G., Kuruvilla, G., Kuruvilla, P., Lowe, D., Kwok, K., Blakely, J., Styling, S., Bozek, B., Charles, J., Fell, D., Fell, Da, Goode, E., Grossman, Ld, Matthews, E., Nitkin, R., Ricci, J., Selby, A., Singh, N., Swan, J., Emmett, J., Weingert, M., Ganjavi, F., Hill, D., Nawaz, S., Hessian, R., Kwiatkowski, K., Lai, C., Mulaisho, C., Okeefe, H., Smith, H., Weeks, A., Andrews, J., Barnie, A., Drobac, M., Hacker, P., Hanna, A., Iwanochko, M., Kenshole, A., Langer, A., Liu, P., Maclean, S., Moe, G., Sasson, Z., Sternberg, L., Trachuk, C., Walters, J., Zinman, B., Cheung, M., Cina, C., Yao, L., Man, K., Fulop, J., Glanz, A., Sibbick, M., Carter, P., Hickey, J., Mcmillian, E., Dion, D., Sthilaire, R., Coutu, D., Damours, G., Starra, R., Brooks, J., Dechamps, P., Kiwan, G., Kouz, S., Laforest, M., Remillard, C., Bellamy, D., Brossoit, R., Carrier, S., Houde, A., Labonte, I., Belanger, A., Kandalaft, N., Quenneville, L., Sandi, M., Auger, P., Bilodeau, N., Delage, F., Dumont, F., Giroux, R., Loisel, R., Poirier, C., Saulnier, D., Carmichael, P., Lemay, C., Lenis, J., Arisjilwan, N., Bedard, H., Casavant, C., Chiasson, J., Dagenais, D., Fitchett, D., Gossard, D., Halle, H., Hamel, N., Joyal, M., Magnan, O., Methe, M., Pedneault, L., Pilon, C., Poisson, D., Primeau, L., Rondeau, C., Roy, C., Ruel, M., Serpa, A., Sestier, F., Smilovitch, M., Theroux, P., Beaudoin, J., Boudreault, Jr, D Amours, D., Douville, T., Giguere, G., Houde, G., Labbe, R., Lachance, S., Lessard, L., Mercier, G., Noel, Hp, Talbot, P., Tremblay, J., Karabatsos, A., Maclellan, K., Wilson, P., Bogaty, P., Laforge, D., Langlais, M., Leblanc, M., Samson, M., Turcotte, J., Campeau, J., Dupuis, R., Lauzon, C., Ouimet, F., Pruneau, G., Desmaris, C., Frechetto, I., Gervais, P., James Brophy, Leroux, S., Bester, S., Meunier, L., Sayeed, M., Hart, M., Moumne, I., Thomasse, G., Walker, J., Walker, M., Ahmed, S., Habib, Nm, Kuny, P., Lopez, J., Klein, W., Grisold, M., Heyndrickx, L., Fiasse, A., Degaute, Jp, Mockel, J., Duprez, D., Chaudron, Jm, Bodson, A., Krzentowski, G., Boland, J., Kolendorf, K., Winther, B., Juhl, H., Hamalainen, T., Siitonen, O., Gin, H., Rigalleau, V., Hensen, J., Riel, R., Oehmenbritsch, R., Schulzeschleppinghoff, B., Hopf, R., Moller, A., Rosak, C., Wetzel, H., Hasslacher, C., Martin, T., Stein, J., Erdmann, E., Bohm, M., Hartmann, D., Breidert, M., Fritzen, R., Scherbaum, W., Mann, J., Maus, J., Schroeder, C., Henrichs, H., Unger, H., Ickenstein, G., Kromer, E., Riegger, G., Schunkert, H., Basan, B., Hampel, R., Crean, P., Garadah, T., White, U., Marini, N., Paciaroni, E., Saccomano, G., Diluzio, S., Magnani, B., Mantovani, B., Pareschi, P., Stucchi, N., Nanni, D., Rusticali, F., Simoni, C., Brunelli, C., Caponnetto, S., Gatto, E., Mazzantini, A., Molinari, O., Morello, R., Degiorgio, L., Imparato, C., Barbaresi, F., Cotogni, A., Pasqualini, M., Frigeni, G., Landoni, M., Polese, A., Cernigoi, A., Merni, M., Tortul, C., Velussi, M., Aina, F., Cernigliaro, C., Dellavesa, P., Dejoannon, U., Pierfranceschi, G., Zavaroni, D., Emilia, R., Manicardi, E., Minelli, E., Penazzoli, F., Portioli, I., Rossi, E., Giani, P., Roccaforte, R., Casaccia, M., Larovere, R., Miglierina, E., Repetto, S., Centofante, P., Vincenzi, M., Nieuwenhuijzen, Ac, Sels, J., Wolffenbuttel, Bhr, Kip, J., Mantingh, L., Mulder, H., Vandoorn, Lg, Hjerkinn, E., Reikvam, A., Cardona, M., Sanz, G., Karoni, A., Bescos, Ll, Albert, X., Masia, R., Alvarez, A., Saenz, L., Astrom, L., Press, R., Sjostedt, P., Tabrizi, F., Bergbom, I., Hansson, P., Held, C., Kahan, T., Ryden, B., Andersson, O., Wysocki, M., Karlsson, E., Sartor, G., Smith, L., Katzman, P., Ljungdahl, L., Noren, P., Hallberg, A., Olsson, Po, Asbrink, S., Molgaard, J., Nilsson, V., Nystrom, F., Ohman, P., Andersson, C., Ekholm, L., Svensson, Ka, Torebo, E., Fagher, B., Svenstam, I., Thulin, T., Ericsson, Ub, Ahnberg, K., Henning, R., Jacobsson, L., Taghavi, A., Ahlstrom, P., Rosenqvist, U., Ericson, C., Gertow, O., Kristensson, Be, Stahl, L., Bergsten, L., Harden, R., Jagren, C., Leijd, B., Lennerhagen, P., Ostergrens, J., Sandstrom, V., Sundelin, R., Hagg, A., Morlin, C., Pettersson, F., Wanders, A., Bjorkman, H., Karlsson, G., Larsson, H., Lonndahl, Y., Weber, P., Cozzi, R., Gerber, P., Moccetti, T., Safwan, E., Sessa, F., Binder, T., Boman, P., Kiowski, W., Lehman, R., Lull, B., Spinas, G., Jamieson, A., Kennedy, Ja, Kesson, C., Gryczka, R., Parker, P., Sidiki, S., Small, M., Struthers, S., Manns, J., Smithurst, H., Begg, A., Fisher, Bm, Bedford, C., Heller, S., Marlow, S., Munoz, Ec, Garcia, Hh, Ruiz, Ro, Meaney, E., Flores, Mi, Brown, E., Perry, G., Patel, G., Sarma, R., Szlachcic, Y., Dorman, J., Singh, B., Bailey, G., Clegg, L., Horwitz, L., Leahy, J., Rashkow, A., Hudson, M., Miller, A., Umberger, J., Zoble, R., Orander, P., Sridharan, M., Defrancisco, G., Davidson, M., Islam, N., Mathew, J., Rajanahally, R., French, D., Wickemeyer, W., Effron, M., Goldstein, M., Utley, K., Pierpont, G., Weigenant, J., Farkouh, M., Kubly, V., Rich, M., Wisneski, L., Abrams, J., Garcia, D., Bonora, M., Kohn, R., Muffoletto, E., Brink, D., Lader, E., Singler, A., Pande, P., Powers, J., Hoogwerf, B., Moore, J., Yanak, F., Gupta, S., Williams, D., Danisa, K., Kirk, C., Wescott, B., Grover, J., Mackenzie, M., Amidi, M., Bell, M., Farmer, J., Kingry, C., Young, J., Harms, V., Kennedy, Jw, Letterer, R., Heller, C., and Mack, R.

12. Family medicine in 2018,La médecine familiale en 2018

Author

Ogle, K. D., Boulé, R., Boyd, R. J., Brown, G., Cervin, C., Dawes, M., Freeman, T., Marie Giroux, Lehmann, F., Lemelin, J., Lortie, G., Maclean, C., Miller, R., Price, D., Smith, P., Spooner, G. R., Wilson, L., and Woollard, R.

14. Effect of multiple-antibiotic treatments on the evolution of antibiotic resistance in Pseudomonas aeruginosa

Author

Whiteley, R, Griffin, A, Knight, C, Maclean, C, Maiden, M, and McLean, A

Abstract

To combat the ever-growing clinical burden imposed by antibiotic-resistant pathogens, multiple-antibiotic treatments are increasingly being considered as promising treatment options. The impact of multiple-antibiotic treatments on the evolution of resistance is not well understood however, and debate is ongoing about the effectiveness of various multiple-antibiotic treatments. In this thesis, I investigate how aspects of multiple-antibiotic treatments impact the rate of evolution of antibiotic resistance in the opportunistic human pathogen Pseudomonas aeruginosa. In particular, I look at the impact of interactions between antibiotics in combination on the evolution of resistance, and how creating heterogeneity in the antibiotic environment by rotating the antibiotics used may change the rate of evolution of resistance. I characterise the interactions present in 120 combinations of antibiotics and find that the type of interaction can be predicted by the mechanism of action of the antibiotics involved. I investigate the effect of a subset of these combinations on the evolution of antibiotic resistance. My results refute the influential but poorly-evidenced hypothesis that synergistic combinations accelerate the evolution of resistance, even when synergistic combinations have the same inhibitory effect on sensitive bacteria as additive or antagonistic antibiotic combinations. I focus on a combination of the antibiotics ceftriaxone and sulfamethoxazole and test whether it is more effective in preventing the evolution of resistance than predicted by the inhibitory effect of the combination on sensitive bacteria. I do not find the combination to be more effective than predicted. Finally, I create heterogeneous antibiotic environments by rotating the antibiotic present at different rates. For the first time in a laboratory setting, I test how varying the rate of fluctuation in the antibiotics present in a heterogeneous antibiotic environment impacts the rate of evolution of resistance. Unexpectedly, I find the rate of evolution of resistance increases with increasing levels of antibiotic heterogeneity.

Published
2016

15. Convex bodies appearing as Okounkov bodies of divisors

Author

Victor Lozovanu, Alex Küronya, Catriona Maclean, Kuronya, A, Lozovanu, V, and Maclean, C

Subjects
Pure mathematics, Mathematics(all), Divisor, General Mathematics, Algebraic variety, Fano plane, Mathematics - Algebraic Geometry, Mathematics::Algebraic Geometry, Algebraic surface, Line bundle, Mathematics::Quantum Algebra, Linear series, Okounkov body, FOS: Mathematics, Mathematics - Combinatorics, Mathematics::Representation Theory, Algebraic Geometry (math.AG), Projective variety, Mathematics, Mathematics::Combinatorics, Mathematics::Commutative Algebra, Algebra, 14C20, 14J99, Mathematics, algebraic geometry, convex geometry, asymptotic invariant, linear series, divisor, Okounkov body, Newton polygon, Convex body, Combinatorics (math.CO), Variety (universal algebra), MAT/03 - GEOMETRIA, Flag (geometry)
Abstract

Based on the work of Okounkov (\cite{Ok96}, \cite{Ok03}), Lazarsfeld and Musta\c t\u a (\cite{LM08}) and Kaveh and Khovanskii (\cite{KK08}) have independently associated a convex body, called the Okounkov body, to a big divisor on a smooth projective variety with respect to a complete flag. In this paper we consider the following question: what can be said about the set of convex bodies that appear as Okounkov bodies? We show first that the set of convex bodies appearing as Okounkov bodies of big line bundles on smooth projective varieties with respect to admissible flags is countable. We then give a complete characterisation of the set of convex bodies that arise as Okounkov bodies of $\R$-divisors on smooth projective surfaces. Such Okounkov bodies are always polygons, satisfying certain combinatorial criteria. Finally, we construct two examples of non-polyhedral Okounkov bodies. In the first one, the variety we deal with is Fano and the line bundle is ample. In the second one, we find a Mori dream space variety such that under small perturbations of the flag the Okounkov body remains non-polyhedral., Comment: 16 pages

Published
2012
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