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139 results on '"Wahl N"'

1. Ribbon braids and related operads

Author

Wahl, N.

Subjects
510, Algebraic topology
Abstract

This thesis consists of two parts, both being concerned with operads related to the ribbon braid groups. In the first part, we define a notion of semidirect product for operads and use it to study the framed $n$-discs operad (the semidirect product $f\mathcal{D}_n=\mathcal{D}_n\rtimes SO(n)$ of the little $n$-discs operad with the special orthogonal group). This enables us to deduce properties of $f\mathcal{D}_n$ from the corresponding properties for $\mathcal{D}_n$. We prove an equivariant recognition principle saying that algebras over the framed $n$-discs operad are $n$-fold loop spaces on $SO(n)$-spaces. We also study the operations induced on homology, showing that an $H(f\mathcal{D}_n)$-algebra is a higher dimensional Batalin-Vilkovisky algebra with some additional operators when $n$ is even. Contrastingly, for $n$ odd, we show that the Gerstenhaber structure coming from the little $n$-discs does not give rise to a Batalin-Vilkovisky structure. We give a general construction of operads from families of groups. We then show that the operad obtained from the ribbon braid groups is equivalent to the framed 2-discs operad. It follows that the classifying spaces of ribbon braided monoidal categories are double loop spaces on $S^1$-spaces. The second part of this thesis is concerned with infinite loop space structures on the stable mapping class group. Two such structures were discovered by Tillmann. We show that they are equivalent, constructing a map between the spectra of deloops. We first construct an `almost map', i.e a map between simplicial spaces for which one of the simplicial identities is satisfied only up to homotopy. We show that there are higher homotopies and deduce the existence of a rectification. We then show that the rectification gives an equivalence of spectra.

Published
2001

3. Experimental dosimetric validation of an open-source treatment planning system for IMPT dose delivery at a horizontal PBS research beamline

Author

Sepúlveda, C., (0000-0002-3522-7462) Gebauer, B., (0000-0002-5821-3135) Hoffmann, A. L., Lühr, A., Wahl, N., Burigo, L., Sepúlveda, C., (0000-0002-3522-7462) Gebauer, B., (0000-0002-5821-3135) Hoffmann, A. L., Lühr, A., Wahl, N., and Burigo, L.

Abstract

Objectives: This study investigates the ability of the open-source treatment planning system (TPS) matRad to generate accurate intensity-modulated proton therapy (IMPT) plans for a real-world horizontal proton pencil beam scanning (PBS) research beamline. Initial validation for IMPT dose delivery is addressed by comparing simulation data with measurements. Materials and Methods: The PBS delivery was modelled with Monte Carlo (MC) simulations using TOPAS version 3.7. First, base data measurements were performed to develop a proton beam model (BM) for the OncoRay horizontal PBS research beamline. Data include spot sizes in air, depth-dose profiles and a monitor unit (MU) calibration. BM data was then integrated into matRad to build base-data for IMPT treatment planning. For initial validation of dose delivery, simple 3D box plans were generated at three depths (target beam entrance at 10, 15 and 20cm) covering energies from 115 to 195MeV. Absolute and relative doses were measured using a Semiflex 31013 ionization chamber (PTW Dosimetry) and a scintillation detector (Lynx®, IBA Dosimetry), respectively. Results: Simulations and dose measurements showed good agreement of relative dose profiles at depths of 14.75, 18.05 and 24.05cm for field sizes of 5 x 5, 10 x 10 and 15 x 15cm2. The overall absolute difference of measured and planned target doses was ~1% (see Table 1). Conclusions: Accurate MC-based BM was calculated and integrated into the TPS toolkit matRad. Absolute and relative measurements were in agreement with planned IMPT data. Full validation will be completed next months, including absolute and relative dosimetry of patient plans.

Published
2023

5. Long-term (180-day) outcomes in critically ill patients with COVID-19 in the REMAP-CAP randomized clinical trial

Author

Florescu, S, Stanciu, D, Zaharia, M, Kosa, A, Codreanu, D, Kidwai, A, Masood, S, Kaye, C, Coutts, A, MacKay, L, Summers, C, Polgarova, P, Farahi, N, Fox, E, McWilliam, S, Hawcutt, D, Rad, L, O’Malley, L, Whitbread, J, Jones, D, Dore, R, Saunderson, P, Kelsall, O, Cowley, N, Wild, L, Thrush, J, Wood, H, Austin, K, Bélteczki, J, Magyar, I, Fazekas, Á, Kovács, S, Szőke, V, Donnelly, A, Kelly, M, Smyth, N, O’Kane, S, McClintock, D, Warnock, M, Campbell, R, McCallion, E, Azaiz, A, Charron, C, Godement, M, Geri, G, Vieillard-Baron, A, Johnson, P, McKenna, S, Hanley, J, Currie, A, Allen, B, McGoldrick, C, McMaster, M, Mani, A, Mathew, M, Kandeepan, R, Vignesh, C, TV, B, Ramakrishnan, N, James, A, Elvira, E, Jayakumar, D, Pratheema, R, Babu, S, Ebenezer, R, Krishnaoorthy, S, Ranganathan, L, Ganesan, M, Shree, M, Guilder, E, Butler, M, Cowdrey, K-A, Robertson, M, Ali, F, McMahon, E, Duffy, E, Chen, Y, Simmonds, C, McConnochie, R, O’Connor, C, El-Khawas, K, Richardson, A, Hill, D, Commons, R, Abdelkharim, H, Saxena, M, Muteithia, M, Dobell-Brown, K, Jha, R, Kalogirou, M, Ellis, C, Krishnamurthy, V, O’Connor, A, Thurairatnam, S, Mukherjee, D, Kaliappan, A, Vertue, M, Nicholson, A, Riches, J, Maloney, G, Kittridge, L, Solesbury, A, Ramos, A, Collins, D, Brickell, K, Reid, L, Smyth, M, Breen, P, Spain, S, Curley, G, McEvoy, N, Geoghegan, P, Clarke, J, Silversides, J, McGuigan, P, Ward, K, O’Neill, A, Finn, S, Wright, C, Green, J, Collins, É, Knott, C, Smith, J, Boschert, C, Slieker, K, Ewalds, E, Sanders, A, Wittenberg, W, Geurts, H, Poojara, L, Sara, T, Nand, K, Reeve, B, Dechert, W, Phillips, B, Oritz-Ruiz de Gordoa, L, Affleck, J, Shaikh, A, Murray, A, Ramanan, M, Frakking, T, Pinnell, J, Robinson, M, Gledhill, L, Wood, T, Sanghavi, R, Bhonagiri, D, Ford, M, Parikh, HG, Avard, B, Nourse, M, McDonald, B, Edmunds, N, Hoiting, O, Peters, M, Rengers, E, Evers, M, Prinssen, A, Morgan, M, Cole, J, Hill, H, Davies, M, Williams, A, Thomas, E, Davies, R, Wise, M, Grimm, P, Soukup, J, Wetzold, R, Löbel, M, Starke, L, Lellouche, F, Lizotte, P, Declerq, P, Antoine, M, Stephanie, G, Jean-Pierre, E, François, B, Marion, B, Philippe, R, Pourcine, F, Monchi, M, Luis, D, Mercier, R, Sagnier, A, Verrier, N, Caplin, C, Richecoeu, J, Combaux, D, Siami, S, Aparicio, C, Vautier, S, Jeblaoui, A, Lemaire-Brunel, D, D'Aragon, F, Carbonneau, E, Leblond, J, Plantefeve, G, Leparco, C, Contou, D, Fartoukh, M, Courtin, L, Labbe, V, Voiriot, G, Salhi, S, Chassé, M, Carrier, F, Boumahni, D, Benettaib, F, Ghamraoui, A, Sement, A, Gachet, A, Hanisch, A, Haffiane, A, Boivin, A-H, Barreau, A, Guerineau, E, Poupblanc, S, Egreteau, P, Lefevre, M, Bocher, S, Le Loup, G, Le Guen, L, Carn, V, Bertel, M, Antcliffe, D, Templeton, M, Rojo, R, Coghlan, P, Smee, J, Barker, G, Finn, A, Kreb, G, Hoff, U, Hinrichs, C, Nee, J, Mackay, E, Cort, J, Whileman, A, Spencer, T, Spittle, N, Beavis, S, Padmakumar, A, Dale, K, Hawes, J, Moakes, E, Gascoyne, R, Pritchard, K, Stevenson, L, Cooke, J, Nemeth-Roszpopa, K, Gauli, B, Bastola, S, Muller, G, Nay, M-A, Kamel, T, Benzekri, D, Jacquier, S, Runge, I, Mathonnet, A, Barbier, F, Bretagnol, A, Carter, J, Van Der Heyden, K, Mehrtens, J, Morris, A, Morgan, S, Burke, T, Mercier, E, Chartier, D, Salmon, C, Dequin, P-F, Garot, D, Bellemare, D, Cloutier, È, Daher, R, Costerousse, O, Boulanger, M-C, Couillard-Chénard, É, Lauzier, F, Francoeur, C, Francois, B, Gay, A, Anne-Laure, F, Ramali, M, HC, O, Ghosh, A, Osagie, R, Arachchige, M, Hartley, M, Cheung, W, Wong, H, Seigne, P, Eustace, J, O'Callaghan, A-M, O'Brien, F, Bamford, P, Reid, A, Cawley, K, Faulkner, M, Pickering, C, Raj, A, Tsinaslanidis, G, Khade, R, Agha, G, Sekiwala, R, Smith, T, Brewer, C, Gregory, J, Limb, J, Cowton, A, O’Brien, J, Postlethwaite, K, Malakouti, S, Music, E, Ricketts, D, King, A, Clermont, G, Bart, R, Mayr, F, Schoenling, A, Andreae, M, Shetty, V, Brant, E, Malley, B, Donadee, C, Sackrowitz, R, Weissman, A, Yealy, D, Barton, D, Talia, N, Nikitas, N, Wells, C, Lankester, L, McMillan, H, Van den Oever, H, Kruisdijk-Gerritsen, A, Haidar, G, Bain, W, Barbash, I, Fitzpatrick, M, Franz, C, Kitsios, G, Moghbeli, K, Rosborough, B, Shah, F, Suber, T, Pulletz, M, Williams, P, Birch, J, Wiseman, S, Horton, S, Alegria, A, Turki, S, Elsefi, T, Crisp, N, Allen, L, Truman, N, Smith, M, Chukkambotla, S, Goddard, W, Duberley, S, Khan, M, Kazi, A, Simpson, J, Duke, G, Chan, P, Carter, B, Hunter, S, Voigt, I, Schueler, R, Blank, E, Hüning, V, Steffen, M, Goralski, P, Litton, E, Regli, A, Pellicano, S, Palermo, A, Eroglu, E, Bihari, S, Laver, RD, Jin, X, Brown, J, McIntyre, J, French, C, Bates, S, Towns, M, Yang, Y, McGain, F, McCullagh, I, Cairns, T, Hanson, H, Patel, B, Clement, I, Evetts, G, Touma, O, Holland, S, Hodge, C, Taylor, H, Alderman, M, Barnes, N, Da Rocha, J, Smith, C, Brooks, N, Weerasinghe, T, Sinclair, J-A, Abusamra, Y, Doherty, R, Cudlipp, J, Singh, R, Yu, H, Daebis, A, Ng, C, Kendrick, S, Saran, A, Makky, A, Greener, D, Rowe-Leete, L, Edwards, A, Bland, Y, Dolman, R, Foster, T, Laffey, J, McNicholas, B, Scully, M, Casey, S, Kernan, M, Brennan, A, Rangan, R, Tully, R, Corbett, S, McCarthy, A, Duffy, O, Burke, D, Linnett, V, Sanderson, A, Ritzema, J, Wild, H, Lucas, R, Marriott, Y, Andric, Z, Cviljevic, S, Br, R, Zapalac, M, Mirković, G, Khare, D, Pinder, M, Gopinath, A, Kannan, T, Dean, S, Vanmali, P, Depuydt, P, De Waele, J, De Bus, L, Fierens, J, Bracke, S, Vermassen, J, Vermeiren, D, Pugh, R, Lean, R, Qiu, X, Scanlan, J, Evans, A, Davies, G, Lewis, J, Plesnikova, Y, Khoud, A, Coetzee, S, Puxty, K, Cathcart, S, Rimmer, D, Bagot, C, Scott, K, Martin, L, Yusuff, H, Isgro, G, Brightling, C, Bourne, M, Craner, M, Boyles, R, Alexander, B, Roberts, T, Nelli, A, Rosenstein-Sisson, R, Speyer, R, Pech, Y, McCullough, J, Tallott, M, Vazquez-Grande, G, Marten, N, Liu, T, Siddiqui, A, Khanal, S, Amatya, S, Szakmany, T, Cherian, S, Williams, G, James, C, Waters, A, Prout, R, Stedman, R, Davies, L, Pegler, S, Kyeremeh, L, Moorhouse, L, Arbane, G, Marotti, M, Bociek, A, Campos, S, Van Nieuwkoop, K, Ottens, T, Visser, Y, Van den Berg, L, Van der Kraan-Donker, A, Brett, S, Arias, S, Hall, R, Paneru, H, Koirala, S, Paudel, P, Wilson, M, Vaara, S, Pettilä, L, Heinonen, J, Pettilä, V, Jain, S, Gupta, A, Holbrook, C, Antoine, P, Meziani, F, Allam, H, Cattelan, J, Clere-Jehl, R, Helms, J, Kummerlen, C, Merdji, H, Monnier, A, Rahmani, H, Studer, A, Schneider, F, Castelain, V, Morel, G, L’Hotellier, S, Ochin, E, Vanjak, C, Rouge, P, Bendjemar, L, Albert, M, Serri, K, Cavayas, A, Duplaix, M, Williams, V, Catorze, NJTADS, Pereira, TNAL, Ferreira, RMC, Bastos, JMPS, Batista, TMO, Badie, J, Berdaguer, F, Malfroy, S, Mezher, C, Bourgoin, C, Moneger, G, Bouvier, E, Muñoz-Bermúdez, R, Marin-Corral, J, Degracia, A, Gómez, F, López, M, Aceto, R, Aghemo, A, Badalamenti, S, Brunetta, E, Cecconi, M, Ciccarelli, M, Constantini, E, Greco, M, Folci, M, Selmi, C, Voza, A, Henning, J, Bonner, S, Hugill, K, Cirstea, E, Wilkinson, D, Jones, J, Altomy, M, Karlikowski, M, Sutherland, H, Wilhelmsen, E, Woods, J, North, J, Pletz, M, Hagel, S, Ankert, J, Kolanos, S, Bloos, F, Simons, K, Van Zuylen, T, Bouman, A, Kumar, N, Panwar, R, Poulter, A-L, Sunkara, K, Szigligeti, G, Leszkoven, J, Rochwerg, B, Karachi, T, Oczkowski, S, Centofanti, J, Millen, T, Sundaran, D, Hollos, L, Turns, M, Walsh, J, Al Qasim, E, Alswaidan, L, Hegazy, M, Arishi, H, Al Amri, A, AlQahtani, S, Naidu, B, Tlayjeh, H, Hussain, S, Al Enezi, F, Abdukahil, SA, Hopkins, P, Noble, H, O’Reilly, K, Mehta, R, Wong, O, Makanju, E, Rao, D, Sikondari, N, Saha, S, Corcoran, E, Pappa, E, Cockrell, M, Donegan, C, Balaie, M, Nickoleit-Bitzenberger, D, Schaaf, B, Meermeier, W, Prebeg, K, Azzaui, H, Hower, M, Brieger, K-G, Elender, C, Sabelhaus, T, Riepe, A, Akamp, C, Kremling, J, Klein, D, Landsiedel-Mechenbier, E, Laha, S, Verlander, M, Jha, A, Megarbane, B, Voicu, S, Deye, N, Malissin, I, Sutterlin, L, Mrad, A, Lehalleur, A, Naim, G, Nguyen, P, Ekhérian, J-M, Boué, Y, Sidéris, G, Vodovar, D, Guérin, E, Grant, C, Brain, M, Mineall, S, Paramasivam, E, Wilby, E, Ogg, B, Howcroft, C, Aspinwall, A, Charlton, S, Gould, R, Mistry, D, Awan, S, Bedford, C, Carr-Wilkinson, J, Hall, A, Gardiner-Hill, C, Maloney, C, Brunskill, N, Watchorn, O, Hardy, C, Qureshi, H, Flint, N, Nicholson, S, Southin, S, Ghattaoraya, A, Harding, D, O’Halloran, S, Collins, A, Smith, E, Trues, E, Borgatta, B, Turner-Bone, I, Reddy, A, Wilding, L, Wilson, C, Surti, Z, Aneman, A, Miller, J, White, H, Estensen, K, Morrison, L, Sutton, J, Cooper, M, Warnapura, L, Agno, R, Sathianathan, P, Shaw, D, Ijaz, N, Spong, A, Sabaretnam, S, Burns, D, Lang, E, Tate, M, Fischer, R, Biradar, V, Soar, N, Golden, D, Davey, M, Seaman, R, Osborne, A, Bannard-Smith, J, Clark, R, Birchall, K, Henry, J, Pomeroy, F, Quayle, R, Wylie, K, Sukuraman, A, John, M, Sibin, S, Leditschke, A, Finnis, M, Jongebloed, K, Khwaja, K, Campisi, J, Van Vonderen, M, Pietersma, M, Vrolijk, L, Kampschreur, L, Van Gulik, L, Makowski, A, Misztal, B, Haider, S, Liao, A, Squires, R, Oborska, A, Kayani, A, Kalchko-Veyssal, S, Prabakaran, R, Hadebe, B, KalchkoVeyssal, S, Williams, T, Song, R, Morpeth, S, Lai, V, Habraken, H, Stewart, R, Mwaura, E, Mew, L, Wren, L, Willams, F, Sutherland, S-B, Rebello, R, Shehabi, Y, Al-Bassam, W, Hulley, A, Kadam, U, Sathianathan, K, Innes, R, Doble, P, Graham, L, Shovelton, C, Dean, T, Salahuddin, N, Aryal, D, Koirala, K, Rai, N, Luitel, S, Seppelt, I, Whitehead, C, Lowrey, J, Gresham, R, Masters, K, Hamlyn, V, Hawkins, N, Roynon-Reed, A, Cutler, S, Lewis, S, Lazaro, J, Newman, T, Aravindan, L, Asghar, A, Bartholomew, J, Bayne, M, Beddows, S, Birch, C, Brend, M, Byrne, R, Campbell, D, Campbell, H, Chambers, E, Clinton, A, Collins, J, Crawshaw, S, Dawson, LA, Donaldson, K, Drake, C, Dyas, S, Ellis, Y, Gilmour, K, Goodwin, J, Halden, S, Hall, AS, Hanson, J, Harper, H, Harrison, S, Hayes, A, Hodgson, H, Hurford, S-A, Jackson, S, Levett, C, Lock, S, Lockett, T, Logan, M, Lomme, K, Luo, J, Marsh, E, Mguni, N, Monaghan, H, Murphy, S, Muzengi, N, Naz, M, O'Kell, E, Oliver, A, O'Reilly, J, Pearson, K, Porter, D, Potter, A, Rook, C, Rounds, C, Sheffield, J, Shirley, K, Siewersk, C, Skinner, T, Speight, H, Sutu, M, Unsworth, A, Van’t Hoff, W, Walker, S, Williams, H, Williamson, D, Williamson, JD, Duan, E, Tsang, J, Patterson, L, Austin, P, Chapman, S, Cabrelli, L, Fletcher, S, Nortje, J, Fottrell-Gould, D, Randell, G, Stammers, K, Healey, G, Pinto, M, Borrill, Z, Duncan, T, Ustianowski, A, Uriel, A, Eltayeb, A, Alfonso, J, Hey, S, Shaw, J, Fox, C, Lindergard, G, Charles, B, Blackledge, B, Connolly, K, Harris, J, Cuesta, J, Xavier, K, Purohit, D, Elhassan, M, Haldeos, A, Vincent, R, Abdelrazik, M, Jenkins, S, Ganesan, A, Kumar, R, Carter, D, Bakthavatsalam, D, Frater, A, Saleem, M, Everitt, R, Hacking, D, Zaman, M, Elmahi, E, Jones, A, Hall, K, Phillips, M, Terrill, L, Mills, G, Raithatha, A, Bauchmuller, K, Ryalls, K, Harrington, K, Bowler, H, Sall, J, Bourne, R, Gross, J, Massey, N, Adebambo, O, Long, M, Tony, K, Juffermans, N, Koopmans, M, Dujardin, R, Alderink, B, Rowland, M, Hutton, P, Bashyal, A, Davidson, N, Hird, C, Chhablani, M, Phalod, G, Kirkby, A, Archer, S, Netherton, K, Reschreiter, H, Camsooksai, J, Patch, S, Humphrey, C, Flynn, G, Harrington, C, Kruger, P, Walsham, J, Meyer, J, Harward, M, Jones, C, Sathe, S, Roche, L, Davies, E, Skinner, D, Gaylard, J, Newman, J, Pogson, D, Rose, S, Daly, Z, Brimfield, L, Nown, A, Parekh, D, Bergin, C, Bates, M, McGhee, C, Lynch, D, Bhandal, K, Tsakiridou, K, Bamford, A, Cooper, L, Whitehouse, T, Veenith, T, Forster, E, O'Connell, M, Sim, M, Hay, S, Henderson, S, Nygren, M, Valentine, E, Katary, A, Bell, G, Wilcox, L, Mataliotakis, M, Smith, P, Ali, M, Isguzar, A, Phull, M-K, Zaidi, A, Pogreban, T, Rosaroso, L, Harvey, D, Lowe, B, Meredith, M, Ryan, L, Schouten, J, Pickkers, P, Roovers, N, Klop-Riehl, M, Van der Eng, H, Sloots-Cuppen, S, Preijers, L, Van Oosten, N, Moine, P, Heming, N, Maxime, V, Bossard, I, Nicholier, T, Clair, B, Orlikowski, D, Bounab, R, Abdeladim, L, Baker, S, Duroux, M, Ratcliffe, M, Sy, E, Mailman, J, Lee, S, Gupta, C, Kassir, S, López, R, Rodríguez-Gómez, J, Cárcel, S, Carmona, R, De la Fuente, C, Rodriguez, M, Jan Hassing, R, Greven, F, Huijbens, D, Roebers, L, Verheij, H, Miles, H, Attokaran, A, Buehner, U, Williams, E, Chapman, M, O’Connor, S, Glasby, K, Rivett, J, Brown, N, Kutsogiannis, D, Thompson, P, Rooney, K, Rodden, N, Thomson, N, McGlynn, D, Abel, L, Gemmell, L, Sundaram, R, Hornsby, J, Walden, A, Keating, L, Frise, M, Rai, S, Bartley, S, Schuster-Bruce, M, Pitts, S, Miln, R, Purandare, L, Vamplew, L, Dempster, D, Gummadi, M, Dormand, N, Wang, S, Spivey, M, Bean, S, Burt, K, Moore, L, Hammonds, F, Richards, C, Campbell, L, Smyth, K, Day, C, Zitter, L, Benyon, S, Singh, J, Lynch, C, Mikusek, J, Deacon, B, Turner, K, Baker, E, Hickey, J, Champanerkar, S, Aitken, L, LewisProsser, L, Ahmad, N, Wiles, M, Willson, J, Grecu, I, Martin, J, Wrey Brown, C, Arias, A-M, Bevan, E, Westlake, S, Craven, T, Hope, D, Singleton, J, Clark, S, McCulloch, C, Biddie, S, Welters, I, Hamilton, D, Williams, K, Waugh, V, Mulla, S, Waite, A, Roman, J, Martinez, M, Johnston, B, Puthucheary, Z, Martin, T, Santos, F, Uddin, R, Fernandez, M, Seidu, F, Somerville, A, Pakats, M-L, Begum, S, Shahid, T, Presneill, J, Barge, D, Byrne, K, Janin, P, Yarad, E, Bass, F, Hammond, N, Vuylsteke, A, Chan, C, Victor, S, Waterson, S, McNamara, R, Boardman, M, Gattas, D, Buhr, H, Coles, J, Matsa, R, Gellamucho, M, Creagh-Brown, B, Marriot, C, Salberg, A, Zouita, L, Stone, S, Michalak, N, Donlon, S, Mtuwa, S, Mayangao, I, Verula, J, Burda, D, Harris, C, Jones, E, Bradley, P, Tarr, E, Harden, L, Piercy, C, Nolan, J, Kerslake, I, Cook, T, Simpson, T, Dalton, J, Demetriou, C, Mitchard, S, Ramos, L, White, K, Johnson, T, Headdon, W, Spencer, S, White, A, Howie, L, Reay, M, Watts, A, Traverse, E, Jennings, S, Anumakonda, V, Tuckwell, C, Harrow, K, Matthews, J, McGarry, K, Moore, V, Smith, L, Summerfield, A, Dark, P, Harvey, A, Doonan, R, McMorrow, L, Knowles, K, Pendlebury, J, Perez, J, Marsden, T, Taylor, M, Michael, A, Collis, M, Claxton, A, Habeichi, W, Horner, D, Slaughter, M, Thomas, V, Proudfoot, N, Keatley, C, Donnison, P, Casey, R, Irving, B, Matimba-Mupaya, W, Reed, C, Anthony, A, Trim, F, Cambalova, L, Robertson, D, Wilson, A, Hulme, J, Kannan, S, Kinney, F, Senya, H, Ratnam, V, Gill, M, Kirk, J, Shelton, S, Schweikert, S, Wibrow, B, Anstey, M, Rauniyar, R, Khoso, N, Asif, N, Taqdees, H, Frey, C, Scano, R, McKee, M, Murphy, P, Thomas, M, Worner, R, Faulkner, B, Gendall, E, Hayes, K, Blakemore, H, Borislavova, B, Deshpande, K, Van Haren, F, Konecny, P, Inskip, D, Tung, R, Hayes, L, Murphy, L, Neill, A, Reidy, B, O’Dwyer, M, Ryan, D, Ainscough, K, Hamilton-Davies, C, Mfuko, C, Abbass, H, Mandadapu, V, Leaver, S, Patel, K, Farnell-Ward, S, Saluzzio, R, Rawlins, S, Sicat, C, De Keulenaer, B, Ferrier, J, Fysh, E, Davda, A, Mevavala, B, Cook, D, Clarke, F, Banach, D, Fernández de Pinedo Artaraz, Z, Cabreros, L, Latham, V, Kruisselbrink, R, Brochard, L, Burns, K, Sandhu, G, Khalid, I, White, I, Croft, M, Holland, N, Pereira, R, Nair, P, Buscher, H, Reynolds, C, Newman, S, Santamaria, J, Barbazza, L, Homes, J, Smith, R, Zaki, A, Johnson, D, Garrard, H, Juhaz, V, Brown, L, Pemberton, A, Roy, A, Rostron, A, Woods, L, Cornell, S, Fowler, R, Adhikari, N, Kamra, M, Marinoff, N, Garrett, P, Murray, L, Brailsford, J, Fennessy, G, Mulder, J, Morgan, R, Pillai, S, Harford, R, Ivatt, H, Evans, D, Richards, S, Roberts, E, Bowen, J, Ainsworth, J, Kuitunen, A, Karlsson, S, Vahtera, A, Kiiski, H, Ristimäki, S, Albrett, J, Jackson, C, Kirkham, S, Tamme, K, Reinhard, V, Ellervee, A, Põldots, L, Rennit, P, Svitškar, N, Browne, T, Grimwade, K, Goodson, J, Keet, O, Callender, O, Udy, A, McCracken, P, Young, M, Board, J, Martin, E, Kasipandian, V, Patel, A, Allibone, S, Mary-Genetu, R, English, S, Watpool, I, Porteous, R, Miezitis, S, McIntyre, L, Brady, K, Vale, C, Shekar, K, Lavana, J, Parmar, D, Peake, S, Kurenda, C, Hormis, A, Walker, R, Collier, D, Kimpton, S, Oakley, S, Bhagani, S, De Neef, M, Garcia, S, Maharajh, A, Nandani, A, Dobson, J, Fernando, G, Eastgate, C, Gomez, K, Abdi, Z, Tatham, K, Jhanji, S, Black, E, Dela Rosa, A, Howle, R, Baikady, R, Drummond, A, Dearden, J, Philbin, J, Munt, S, Gopal, S, Pooni, J-S, Ganguly, S, Smallwood, A, Metherell, S, Naeem, A, Fagan, L, Ryan, E, Mariappa, V, Foulds, A, Revill, A, Bhattarai, B, De Jonge, E, Wigbers, J, Del Prado, M, Cremer, O, Mulier, J, Peters, A, Romberg, B, Schutgens, R, Troeman, D, Van Opdorp, M, Besten, H, Brakké, K, Barber, R, Hilldrith, A, Kluge, S, Nierhaus, A, Jarczak, D, Roedl, K, Kochanek, M, Rueß-Paterno, G, Mc-Kenzie, J, Eichenauer, D, Shimabukuro-Vornhagen, A, Wilcox, E, Del Sorbo, L, Abdelhady, H, Romagnuolo, T, Simpson, S, Maiden, M, Horton, M, Trickey, J, Krajinovic, V, Kutleša, M, Kotarski, V, Brohi, F, Jagannathan, V, Clark, M, Purvis, S, Wetherill, B, Brajković, A, Babel, J, Sever, H, Dragija, L, Kušan, I, Dushianthan, A, Cusack, R, De Courcy-Golder, K, Salmon, K, Burnish, R, Smith, S, Ruiz, W, Duke, Z, Johns, M, Male, M, Gladas, K, Virdee, S, Swabe, J, Tomlinson, H, Rohde, G, Grünewaldt, A, Bojunga, J, Petros, S, Kunz, K, Schütze, B, Weismann, D, Frey, A, Drayss, M, Goebeler, ME, Flor, T, Fragner, G, Wahl, N, Totzke, J, Sayehli, C, Hakak, S, Altaf, W, O'Sullivan, M, Murphy, A, Walsh, L, Rega La Valle, A, Bewley, J, Sweet, K, Grimmer, L, Johnson, R, Wyatt, R, Morgan, K, Varghese, S, Willis, J, Stratton, E, Kyle, L, Putensen, D, Drury, K, Skorko, A, Bremmer, P, Ward, G, Bassford, C, Sligl, W, Baig, N, Rewa, O, Bagshaw, S, Basile, K, Stavor, D, Burbee, D, McNamara, A, Wunderley, R, Bensen, N, Adams, P, Vita, T, Buhay, M, Scholl, D, Gilliam, M, Winters, J, Doherty, K, Berryman, E, Ghaffari, M, Marroquin, O, Quinn, K, Garrard, W, Kalchthaler, K, Beard, G, Skrtich, A, Bagavathy, K, Drapola, D, Bryan-Morris, K, Arnold, J, Reynolds, B, Hussain, M, Dunsavage, J, Saiyed, S, Hernandez, E, Goldman, J, Brown, C, Comp, S, Raczek, J, Morris, J, Vargas Jr., J, Weiss, D, Hensley, J, Kochert, E, Wnuk, C, Nemeth, C, Mowery, B, Hutchinson, C, Winters, L, McAdams, D, Walker, G, Minnier, T, Wisniewski, M, Mayak, K, McCreary, E, Bariola, R, Viehman, A, Daley, J, Lopus, A, Schmidhofer, M, Ambrosino, R, Keen, S, Toffalo, S, Stambaugh, M, Trimmer, K, Perri, R, Casali, S, Medva, R, Massar, B, Beyerl, A, Burkey, J, Keeler, S, Lowery, M, Oncea, L, Daugherty, J, Sevilla, C, Woelke, A, Dice, J, Weber, L, Roth, J, Ferringer, C, Beer, D, Fesz, J, Carpio, L, Colin, G, Zinzoni, V, Maquigneau, N, Henri-Lagarrigue, M, Pouplet, C, Reill, L, Distler, M, Maselli, A, Martynoga, R, Trask, K, Butler, A, Attwood, B, Parsons, P, Campbell, B, Smith, A, Page, V, Zhao, X, Oza, D, Abrahamson, G, Sheath, B, Young, P, Young, C, Lesona, E, Navarra, L, Cruz, R, Delaney, K, Aguilar-Dano, A, Gojanovic, M, Rhodes, J, Anderson, T, Morris, S, Nayyar, V, Bowen, D, Kong, J, Joy, J, Fuchs, R, Lambert, B, Tai, C, Thomas, A, Keen, A, Tierney, C, Omer, N, Bacon, G, Tridente, A, Shuker, K, Anders, J, Greer, S, Scott, P, Millington, A, Buchanan, P, Binnie, A, Powell, E, McMillan, A, Luk, T, Aref, N, Denmade, C, Sadera, G, Jacob, R, Hughes, D, Sterba, M, Geng, W, Digby, S, Southern, D, Reddy, H, Hulse, S, Campbell, A, Garton, M, Watkins, C, Smuts, S, Quinn, A, Simpson, B, McMillan, C, Finch, C, Hill, C, Cooper, J, Budd, J, Small, C, O’Leary, R, Collins, E, Holland, A, Alexander, P, Felton, T, Ferguson, S, Sellers, K, Ward, L, Yates, D, Birkinshaw, I, Kell, K, Scott, Z, Pearson, H, Hashmi, M, Hassan, N, Panjwani, A, Umrani, Z, Shaikh, M, Ain, Q, Kanwal, D, Van Bree, S, Bouw-Ruiter, M, Osinga, M, Van Zanten, A, McEldrew, R, Rashan, S, Singh, V, Azergui, N, Bari, S, Beltran, M, Brugman, C, Groeneveld, E, Jafarzadeh, M, Keijzer-Timmers, N, Kester, E, Koelink, M, Kwakkenbos-Craanen, M, Okundaye, C, Parker, L, Peters, S, Post, S, Rietveld, I, Scheepstra-Beukers, I, Schreuder, G, Smit, A, Brillinger, N, Markgraf, R, Eichinger, F, Doran, P, Anjum, A, Best-Lane, J, Barton, F, Miller, L, Richards-Belle, A, Saull, M, Sprinckmoller, S, Wiley, D, Darnell, R, Au, C, Lindstrum, K, Cheng, A, Forbes, A, Heritier, S, Trapani, T, Cuthbertson, B, Manoharan, V, Dondrop, A, Tolppa, T, Ehrmann, S, Hullegie, S, Povoa, P, Beasley, R, Daneman, N, McGloughlin, S, Paterson, D, Venkatesh, B, De Jong, M, Uyeki, T, Baillie, K, Netea, M, Orr, K, Patanwala, A, Tong, S, Cooper, N, Galea, J, Leavis, H, Ogungbenro, K, Patawala, A, Rademaker, E, Youngstein, T, Carrier, M, Fergusson, D, Hunt, B, Kumar, A, Laffan, M, Lother, S, Middeldorp, S, Stanworth, S, De Man, A, Masse, M-H, Abraham, J, Arnold, D, Begin, P, Charlewood, R, Chasse, M, Coyne, M, Daly, J, Gosbell, I, Harvala-Simmonds, H, MacLennan, S, McDyer, J, Menon, D, Pridee, N, Roberts, D, Thomas, H, Tinmouth, A, Triulzi, D, Walsh, T, Wood, E, Calfee, C, O’Kane, C, Shyamsundar, M, Sinha, P, Thompson, T, Young, I, Burrell, A, Ferguson, N, Hodgson, C, Orford, N, Phua, J, Baron, R, Epelman, S, Frankfurter, C, Gommans, F, Kim, E, Leaf, D, Vaduganathan, M, Van Kimmenade, R, Sanil, A, Van Beurden, M, Effelaar, E, Schotsman, J, Boyd, C, Harland, C, Shearer, A, Wren, J, Attanayaka, U, Darshana, S, Ishani, P, Udayanga, I, Higgins, AM, Berry, LR, Lorenzi, E, Murthy, S, McQuilten, Z, Mouncey, PR, Al-Beidh, F, Annane, D, Arabi, YM, Beane, A, Van Bentum-Puijk, W, Bhimani, Z, Bonten, MJM, Bradbury, CA, Brunkhorst, FM, Buzgau, A, Buxton, M, Charles, WN, Cove, M, Detry, MA, Estcourt, LJ, Fagbodun, EO, Fitzgerald, M, Girard, TD, Goligher, EC, Goossens, H, Haniffa, R, Hills, T, Horvat, CM, Huang, DT, Ichihara, N, Lamontagne, F, Marshall, JC, McAuley, DF, McGlothlin, A, McGuinness, SP, McVerry, BJ, Neal, MD, Nichol, AD, Parke, RL, Parker, JC, Parry-Billings, K, Peters, SEC, Reyes, LF, Rowan, KM, Saito, H, Santos, MS, Saunders, CT, Serpa-Neto, A, Seymour, CW, Shankar-Hari, M, Stronach, LM, Turgeon, AF, Turner, AM, Van de Veerdonk, FL, Zarychanski, R, Green, C, Lewis, RJ, Angus, DC, McArthur, CJ, Berry, S, Derde, LPG, Gordon, AC, Webb, SA, Lawler, PR, Comm REMAP-CAP Investigators, Apollo - University of Cambridge Repository, Intensive Care Medicine, Université de Versailles Saint-Quentin-en-Yvelines - UFR Sciences de la santé Simone Veil (UVSQ Santé), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Hôpital Raymond Poincaré [Garches], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Pittsburgh Foundation, PF, Amgen, Health Research Board, HRB: CTN 2014-012, Horizon 2020 Framework Programme, H2020: 101003589, Translational Breast Cancer Research Consortium, TBCRC, Canadian Institutes of Health Research, IRSC: 158584, Heart and Stroke Foundation of Canada, HSF, National Institute for Health and Care Research, NIHR, European Commission, EC, National Health and Medical Research Council, NHMRC: 1101719, APP194811, CS-2016-16-011, GNT2008447, RP-2015-06-18, Office of Health and Medical Research, OHMR, Health Research Council of New Zealand, HRC: 16/631, Eisai, Ministère des Affaires Sociales et de la Santé: PHRC-20-0147, Université Pierre et Marie Curie, UPMC, NIHR Imperial Biomedical Research Centre, BRC, Minderoo Foundation, Funding/Support : The Platform for European Preparedness Against (Re-) emerging Epidemics (PREPARE) consortium by the European Union, FP7-HEALTH-2013-INNOVATION-1 (#602525), the Rapid European COVID-19 Emergency Research response (RECOVER) consortium by the European Union’s Horizon 2020 research and innovation programme (#101003589), the Australian National Health and Medical Research Council (#APP1101719), the Australian Medical Research Future Fund (#APP2002132), the Health Research Council of New Zealand (#16/631), the Canadian Institutes of Health Research Strategy for Patient-Oriented Research Innovative Clinical Trials Program Grant (#158584) and the Canadian Institute of Health Research COVID-19 Rapid Research Funding (#447335), the UK National Institute for Health Research (NIHR) and the NIHR Imperial Biomedical Research Centre, the Health Research Board of Ireland (CTN 2014-012), the UPMC Learning While Doing Program, the Translational Breast Cancer Research Consortium, the French Ministry of Health (PHRC-20-0147), the Wellcome Trust Innovations Project (215522), the Minderoo Foundation, the EU Programme Emergency Support Instrument, the NHS Blood and Transplant Research and Development Programme, the Translational Breast Cancer Research Consortium, the NSW Office of Health and Medical Research, Amgen, Eisai, and the Pittsburgh Foundation. Dr Higgins is funded by an NHMRC Emerging Leadership Fellowship (GNT2008447). Dr McQuilten is funded by an NHMRC Emerging Leadership Fellowship (APP194811). Dr Gordon is funded by an NIHR Research Professorship (RP-2015-06-18) and Dr Shankar-Hari by an NIHR Clinician Scientist Fellowship (CS-2016-16-011). Dr Turgeon is the Chairholder of the Canada Research Chair in Critical Care Neurology and Trauma. Dr Lawler is supported by a career award from the Heart and Stroke Foundation of Canada., and European Project: 602525,EC:FP7:HEALTH,FP7-HEALTH-2013-INNOVATION-1,PREPARE(2014)

Subjects
Adult, Male, corticosteroid, [SDV]Life Sciences [q-bio], Critical Illness, lnfectious Diseases and Global Health Radboud Institute for Molecular Life Sciences [Radboudumc 4], antiplatelet, Lopinavir, Adaptive platform trial randomized controlled trial intensive care, pneumonia COVID-19 antiplatelet immunoglobulin antiviral corticosteroid immune modulation anticoagulation, All institutes and research themes of the Radboud University Medical Center, Adrenal Cortex Hormones, Humans, anticoagulation, intensive care, pneumonia, COVID-19 Serotherapy, Original Investigation, Medicine(all), immune modulation, Ritonavir, SARS-CoV-2, COVID-19, Anticoagulants, Bayes Theorem, General Medicine, Middle Aged, antiviral, Receptors, Interleukin-6, Adaptive platform trial, randomized controlled trial, Female, Human medicine, immunoglobulin, Follow-Up Studies, Hydroxychloroquine
Abstract

ImportanceThe longer-term effects of therapies for the treatment of critically ill patients with COVID-19 are unknown.ObjectiveTo determine the effect of multiple interventions for critically ill adults with COVID-19 on longer-term outcomes.Design, Setting, and ParticipantsPrespecified secondary analysis of an ongoing adaptive platform trial (REMAP-CAP) testing interventions within multiple therapeutic domains in which 4869 critically ill adult patients with COVID-19 were enrolled between March 9, 2020, and June 22, 2021, from 197 sites in 14 countries. The final 180-day follow-up was completed on March 2, 2022.InterventionsPatients were randomized to receive 1 or more interventions within 6 treatment domains: immune modulators (n = 2274), convalescent plasma (n = 2011), antiplatelet therapy (n = 1557), anticoagulation (n = 1033), antivirals (n = 726), and corticosteroids (n = 401).Main Outcomes and MeasuresThe main outcome was survival through day 180, analyzed using a bayesian piecewise exponential model. A hazard ratio (HR) less than 1 represented improved survival (superiority), while an HR greater than 1 represented worsened survival (harm); futility was represented by a relative improvement less than 20% in outcome, shown by an HR greater than 0.83.ResultsAmong 4869 randomized patients (mean age, 59.3 years; 1537 [32.1%] women), 4107 (84.3%) had known vital status and 2590 (63.1%) were alive at day 180. IL-6 receptor antagonists had a greater than 99.9% probability of improving 6-month survival (adjusted HR, 0.74 [95% credible interval {CrI}, 0.61-0.90]) and antiplatelet agents had a 95% probability of improving 6-month survival (adjusted HR, 0.85 [95% CrI, 0.71-1.03]) compared with the control, while the probability of trial-defined statistical futility (HR >0.83) was high for therapeutic anticoagulation (99.9%; HR, 1.13 [95% CrI, 0.93-1.42]), convalescent plasma (99.2%; HR, 0.99 [95% CrI, 0.86-1.14]), and lopinavir-ritonavir (96.6%; HR, 1.06 [95% CrI, 0.82-1.38]) and the probabilities of harm from hydroxychloroquine (96.9%; HR, 1.51 [95% CrI, 0.98-2.29]) and the combination of lopinavir-ritonavir and hydroxychloroquine (96.8%; HR, 1.61 [95% CrI, 0.97-2.67]) were high. The corticosteroid domain was stopped early prior to reaching a predefined statistical trigger; there was a 57.1% to 61.6% probability of improving 6-month survival across varying hydrocortisone dosing strategies.Conclusions and RelevanceAmong critically ill patients with COVID-19 randomized to receive 1 or more therapeutic interventions, treatment with an IL-6 receptor antagonist had a greater than 99.9% probability of improved 180-day mortality compared with patients randomized to the control, and treatment with an antiplatelet had a 95.0% probability of improved 180-day mortality compared with patients randomized to the control. Overall, when considered with previously reported short-term results, the findings indicate that initial in-hospital treatment effects were consistent for most therapies through 6 months.

Published
2023
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9. An infinity operad of normalized cacti

Author

Basualdo Bonatto, L, Chettih, S, Linton, A, Raynor, S, Robertson, M, and Wahl, N

Subjects
Mathematics::K-Theory and Homology, Mathematics::Quantum Algebra, Mathematics::Category Theory, FOS: Mathematics, Algebraic Topology (math.AT), Category Theory (math.CT), Mathematics - Category Theory, Geometry and Topology, Mathematics - Algebraic Topology, Mathematics::Algebraic Topology
Abstract

We show that normalized cacti form an $\infty$-operad in the form of a dendroidal space satisfying a weak Segal condition. To do this, we introduce a new topological operad of bracketed trees and an enrichment of the dendroidal category $\Omega$., Comment: 48 pages, many figures, comments welcome!

Published
2020

20. Ribbon braids and related operads

Author

Wahl, N

Abstract

This thesis consists of two parts, both being concerned with operads related to the ribbon braid groups. In the first part, we define a notion of semidirect product for operads and use it to study the framed $n$-discs operad (the semidirect product $f\mathcal{D}_n=\mathcal{D}_n\rtimes SO(n)$ of the little $n$-discs operad with the special orthogonal group). This enables us to deduce properties of $f\mathcal{D}_n$ from the corresponding properties for $\mathcal{D}_n$. We prove an equivariant recognition principle saying that algebras over the framed $n$-discs operad are $n$-fold loop spaces on $SO(n)$-spaces. We also study the operations induced on homology, showing that an $H(f\mathcal{D}_n)$-algebra is a higher dimensional Batalin-Vilkovisky algebra with some additional operators when $n$ is even. Contrastingly, for $n$ odd, we show that the Gerstenhaber structure coming from the little $n$-discs does not give rise to a Batalin-Vilkovisky structure. We give a general construction of operads from families of groups. We then show that the operad obtained from the ribbon braid groups is equivalent to the framed 2-discs operad. It follows that the classifying spaces of ribbon braided monoidal categories are double loop spaces on $S^1$-spaces. The second part of this thesis is concerned with infinite loop space structures on the stable mapping class group. Two such structures were discovered by Tillmann. We show that they are equivalent, constructing a map between the spectra of deloops. We first construct an `almost map', i.e a map between simplicial spaces for which one of the simplicial identities is satisfied only up to homotopy. We show that there are higher homotopies and deduce the existence of a rectification. We then show that the rectification gives an equivalence of spectra.

Published
2016

23. Constructing Conservation Impact: Understanding Monitoring and Evaluation in Conservation NGOs

Author

Wahl??n, Catherine Benson

Subjects
NGOs, organizations, conservation, resource management, Theory, biodiversity
Abstract

"A growing number of scholars critically examine large conservation organisations to explore organisational intentions, practices, and outcomes. In parallel, other scholars have problematised audit cultures, suggesting that these seemingly good practices of evaluation and measurement are not neutral and instead have consequences for governance and power. This article combines literature on conservation NGOs, organisational theory, and audit culture to study the inner workings of conservation and to understand the construction of effectiveness and impact. I draw on semi-structured interviews to examine how a large, international conservation organisation, which I term the World Conservation Organisation (WCO; a pseudonym), coordinates monitoring and evaluation (M&E) processes among its international, national, and local offices. I find individual staff within WCO make varying assumptions about the M&E policies and place different values on M&E, which results in different institutional logics towards M&E and a broader organisational failure to measure progress and reflect upon outcomes. The findings also show difficulties in translating broad organisational goals into specific project activities, underscoring tensions in implementation and limitations in M&E practice. I also find that organisational and managerial pressure to report success is greater than donor pressure, a finding that expands understandings of NGO-donor dynamics."

Published
2014

36. Particle therapy masterclass

Author

Foka Panagiota, Mamaras Aristeidis, Skrjiel Damir, Seco Joao, Graeff Christian, Pulia Marco, Wieser Hans-Peter, and Wahl Niklas

Subjects
Physics, QC1-999
Abstract

The aim of the new Particle Therapy MasterClass (PTMC) was to develop an educational and training environment in which anyone can learn about fundamental and applied research in particle therapy. The PTMC was recently integrated into the International MasterClass 2021 online programme that attracted 1500 students from 37 institutes in 20 countries, worldwide. The PTMC focuses on the topic of cancer treatment, a particularly sensitive and socially relevant topic. The main idea is to (a) provide a basic understanding of cancer radiation therapy, (b) demonstrate that fundamental properties of particle interactions with matter, which are used for detection in physics experiments, are also the basis for treating cancer tumours; and (c) show that the same accelerator technologies are used in both, research laboratories and therapy centres. For the hands-on session, the open-source professional treatment planning software matRad is used, developed for research and training by the German Cancer Research Center – DKFZ. Ultimately, students are shown “what physics has to do with medicine” and what are the various possibilities that physics and STEM studies may open up for job opportunities in fields that are lacking expert personnel.

Published
2022
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41. Orthodontics in 3 millennia. Chapter 2: Entering the modern era

Author

Wahl, N.

Abstract

In the early 1900s, groundbreaking scientists, working without benefit of graduate training and having little precedent, built the orthodontic edifice brick by brick. Kingsley pioneered cleft-palate treatment. Case showed us the importance of facial esthetics. Dewey and Ketcham made the ABO the first certifying board in dentistry. But it was Angle who gave us our first school, journal, society, and practical classification of malocclusion.

Published
2005
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42. Orthodontics in 3 millennia. Chapter 1: Antiquity to the mid-19^t^h century

Author

Wahl, N.

Abstract

Orthodontics had its beginnings in the time of the ancient Egyptians, who used crude metal bands and catgut, but it was not until the late 18th century that the first practical appliances came into use. These were fine-tuned during the early 1900s; today's mechanisms are merely refinements. Major changes occurred when practitioners-originally physicians-began turning their attention from cosmetic ''regulating'' to occlusion and stability, while empiricism gave way to objectivity and the scientific method. The purpose of this article is to review the history of orthodontics from antiquity to the modern era. The article is divided into chapters that will be presented serially in every other issue of the Journal.

Published
2005
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46. Modelling of Landslides with the Material-Point Method

Author

Lars Vabbersgaard Andersen, Søren Andersen, and Wahl, N. A.

Subjects
Hydrogeology, Mechanical equilibrium, Discretization, Slope stability, Material point method, Landslide, Internal friction, Physics::Geophysics, Computer Science Applications, law.invention, Soil dynamics, Computational Mathematics, Computational Theory and Mathematics, law, Cohesion (geology), Geotechnical engineering, Computers in Earth Sciences, Geology
Abstract

A numerical model for studying the dynamic evolution of landslides is presented. The numerical model is based on the Generalized Interpolation Material Point Method. A simplified slope with a house placed on top is analysed. An elasto-plastic material model based on the Mohr-Coulomb yield criterion is employed for the soil. The slide is triggered for the initially stable slope by removing the cohesion of the soil and the slide is followed from the triggering until a state of static equilibrium is again reached. Parameter studies, in which the angle of internal friction of the soil and the degree of discretisation are varied, are presented. A numerical model for studying the dynamic evolution of landslides is presented. The numerical model is based on the Generalized Interpolation Material Point Method. A simplified slope with a house placed on top is analysed. An elasto-plastic material model based on the Mohr-Coulomb yield criterion is employed for the soil. The slide is triggered for the initially stable slope by removing the cohesion of the soil and the slide is followed from the triggering until a state of static equilibrium is again reached. Parameter studies, in which the angle of internal friction of the soil and the degree of discretisation are varied, are presented.

Published
2008
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47. Implementation and validation of a very-high-energy electron model in the matRad treatment planning system.

Author

Sitarz M, Ronga MG, Gesualdi F, Bonfrate A, Wahl N, and De Marzi L

Abstract

Background: While electron beams of up to 20 MeV are commonly used in radiotherapy, the use of very-high-energy electrons (VHEEs) in the range of 100-200 MeV is now becoming a realistic option thanks to the recent advancements in accelerator technology. Indeed, VHEE offers several clinically attractive features and can be delivered using various conformation methods (including scanning, collimation, and focussing) at ultra-high dose rates. To date, there is a lack of research tools for fast simulation of treatment plans using VHEE beams., Purpose: This work aims to implement and validate a simple and fast dose calculation algorithm based on the Fermi-Eyges theory of multiple Coulomb scattering for VHEE radiation therapy, with energies up to 200 MeV. A treatment planning system (TPS) toolkit with VHEE modality would indeed allow for further preclinical investigations, including treatment plan optimization and evaluation, and thus contribute to the gradual introduction of VHEE radiotherapy in clinical practice., Methods: A VHEE pencil beam scanning double Gaussian model was introduced into the open-source TPS matRad environment along with new functions and options dedicated to VHEE dose calculations. Various geometries and field configurations were then calculated in matRad (up to 200 MeV and 15 × 15 cm 2 , with complex bone or lung heterogeneities) and the results were compared to Monte Carlo simulations in the TOPAS/Geant4 toolkit. Two types of beam model (divergent or focused) were also tested. Examples of clinical treatment plans were computed, and the results were compared between the two codes., Results: VHEE modality was fully implemented in matRad with GUI capabilities while preserving all original TPS features. New relevant options such as the importation of specific spot-lists or adjustment of the lateral dose calculation cutoff to optimize the calculation speed were validated. Single spot and square field dose distributions were validated in water alone as well as in clinically relevant inhomogeneities. Dose maps from the VHEE model in matRad were in good agreement with TOPAS (2D gamma index [2%/1 mm] with passing rates superior to 90%, <6% mean dose differences), except for large interface heterogeneities., Conclusions: This work describes the implementation of a simple but efficient VHEE simulation model in matRad. A few configurations were studied in order to validate the model against accurate Monte Carlo simulations, demonstrating its usefulness for carrying out preliminary studies involving VHEE radiotherapy., (© 2024 The Author(s). Medical Physics published by Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine.)

Published
2025
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48. Prompt gamma emission prediction using a long short-term memory network.

Author

Xiao F, Radonic D, Kriechbaum M, Wahl N, Neishabouri A, Delopoulos N, Parodi K, Corradini S, Belka C, Kurz C, Landry G, and Dedes G

Subjects
Humans, Monte Carlo Method, Male, Proton Therapy methods, Prostatic Neoplasms radiotherapy, Prostatic Neoplasms diagnostic imaging, Tomography, X-Ray Computed, Radiotherapy Planning, Computer-Assisted methods, Radiotherapy Dosage, Neural Networks, Computer, Memory, Short-Term, Gamma Rays
Abstract

Objective : To present a long short-term memory (LSTM)-based prompt gamma (PG) emission prediction method for proton therapy. Approach : Computed tomography (CT) scans of 33 patients with a prostate tumor were included in the dataset. A set of 10 7 histories proton pencil beam (PB)s was generated for Monte Carlo (MC) dose and PG simulation. For training (20 patients) and validation (3 patients), over 6000 PBs at 150, 175 and 200 MeV were simulated. 3D relative stopping power (RSP), PG and dose cuboids that included the PB were extracted. Three models were trained, validated and tested based on an LSTM-based network: (1) input RSP and output PG, (2) input RSP with dose and output PG (single-energy), and (3) input RSP/dose and output PG (multi-energy). 540 PBs at each of the four energy levels (150, 175, 200, and 125-210 MeV) were simulated across 10 patients to test the three models. The gamma passing rate (2%/2 mm) and PG range shift were evaluated and compared among the three models. Results : The model with input RSP/dose and output PG (multi-energy) showed the best performance in terms of gamma passing rate and range shift metrics. Its mean gamma passing rate of testing PBs of 125-210 MeV was 98.5% and the worst case was 92.8%. Its mean absolute range shift between predicted and MC PGs was 0.15 mm, where the maximum shift was 1.1 mm. The prediction time of our models was within 130 ms per PB. Significance : We developed a sub-second LSTM-based PG emission prediction method. Its accuracy in prostate patients has been confirmed across an extensive range of proton energies., (Creative Commons Attribution license.)

Published
2024
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49. Proton dose calculation with LSTM networks in presence of a magnetic field.

Author

Radonic D, Xiao F, Wahl N, Voss L, Neishabouri A, Delopoulos N, Marschner S, Corradini S, Belka C, Dedes G, Kurz C, and Landry G

Subjects
Humans, Prostatic Neoplasms radiotherapy, Prostatic Neoplasms diagnostic imaging, Radiation Dosage, Male, Monte Carlo Method, Radiotherapy, Image-Guided methods, Tomography, X-Ray Computed, Magnetic Resonance Imaging, Proton Therapy methods, Magnetic Fields, Radiotherapy Dosage, Radiotherapy Planning, Computer-Assisted methods
Abstract

Objective. To present a long short-term memory (LSTM) network-based dose calculation method for magnetic resonance (MR)-guided proton therapy. Approach. 35 planning computed tomography (CT) images of prostate cancer patients were collected for Monte Carlo (MC) dose calculation under a perpendicular 1.5 T magnetic field. Proton pencil beams (PB) at three energies (150, 175, and 200 MeV) were simulated (7560 PBs at each energy). A 3D relative stopping power cuboid covering the extent of the PB dose was extracted and given as input to the LSTM model, yielding a 3D predicted PB dose. Three single-energy (SE) LSTM models were trained separately on the corresponding 150/175/200 MeV datasets and a multi-energy (ME) LSTM model with an energy embedding layer was trained on either the combined dataset with three energies or a continuous energy (CE) dataset with 1 MeV steps ranging from 125 to 200 MeV. For each model, training and validation involved 25 patients and 10 patients were for testing. Two single field uniform dose prostate treatment plans were optimized and recalculated with MC and the CE model. Results. Test results of all PBs from the three SE models showed a mean gamma passing rate (2%/2 mm, 10% dose cutoff) above 99.9% with an average center-of-mass (COM) discrepancy below 0.4 mm between predicted and simulated trajectories. The ME model showed a mean gamma passing rate exceeding 99.8% and a COM discrepancy of less than 0.5 mm at the three energies. Treatment plan recalculation by the CE model yielded gamma passing rates of 99.6% and 97.9%. The inference time of the models was 9-10 ms per PB. Significance. LSTM models for proton dose calculation in a magnetic field were developed and showed promising accuracy and efficiency for prostate cancer patients., (Creative Commons Attribution license.)

Published
2024
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50. A Novel Inverse Algorithm To Solve the Integrated Optimization of Dose, Dose Rate, and Linear Energy Transfer of Proton FLASH Therapy With Sparse Filters.

Author

Harrison N, Kang M, Liu R, Charyyev S, Wahl N, Liu W, Zhou J, Higgins KA, Simone CB 2nd, Bradley JD, Dynan WS, and Lin L

Subjects
Humans, Animals, Swine, Proton Therapy methods, Linear Energy Transfer, Radiotherapy Planning, Computer-Assisted methods, Radiotherapy Dosage, Algorithms, Lung Neoplasms radiotherapy, Organs at Risk radiation effects, Radiotherapy, Intensity-Modulated methods
Abstract

Purpose: The recently proposed Integrated Physical Optimization Intensity Modulated Proton Therapy (IPO-IMPT) framework allows simultaneous optimization of dose, dose rate, and linear energy transfer (LET) for ultra-high dose rate (FLASH) treatment planning. Finding solutions to IPO-IMPT is difficult because of computational intensiveness. Nevertheless, an inverse solution that simultaneously specifies the geometry of a sparse filter and weights of a proton intensity map is desirable for both clinical and preclinical applications. Such solutions can reduce effective biologic dose to organs at risk in patients with cancer as well as reduce the number of animal irradiations needed to derive extra biologic dose models in preclinical studies., Methods and Materials: Unlike the initial forward heuristic, this inverse IPO-IMPT solution includes simultaneous optimization of sparse range compensation, sparse range modulation, and spot intensity. The daunting computational tasks vital to this endeavor were resolved iteratively with a distributed computing framework to enable Simultaneous Intensity and Energy Modulation and Compensation (SIEMAC). SIEMAC was demonstrated on a human patient with central lung cancer and a minipig., Results: SIEMAC simultaneously improves maps of spot intensities and patient-field-specific sparse range compensators and range modulators. For the patient with lung cancer, at our maximum nozzle current of 300 nA, dose rate coverage above 100 Gy/s increased from 57% to 96% in the lung and from 93% to 100% in the heart, and LET coverage above 4 keV/µm dropped from 68% to 9% in the lung and from 26% to <1% in the heart. For a simple minipig plan, the full-width half-maximum of the dose, dose rate, and LET distributions decreased by 30%, 1.6%, and 57%, respectively, again with similar target dose coverage, thus reducing uncertainty in these quantities for preclinical studies., Conclusions: The inverse solution to IPO-IMPT demonstrated the capability to simultaneously modulate subspot proton energy and intensity distributions for clinical and preclinical studies., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Published
2024
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