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4. Protease inhibitors for the treatment of hepatitis C virus infection

Author

de Leuw, Philipp and Stephan, Christoph

Subjects
direct-acting antiviral, hepatitis C, HIV, NS3/4A protease inhibitor, Infectious and parasitic diseases, RC109-216
Abstract

The hepatitis C virus (HCV) has affected an estimate of 80 million individuals worldwide and is a strain of public health. Around 25–30% of patients in Europe and the US infected with HIV are coinfected with HCV. Despite treatment modalities containing a NS3/4A protease it in combination with pegylated interferon and ribavirin prior to 2013 improved SVR rates, the amount of severe side effects was high. Nowadays, oral direct-acting antivirals (DAAs) combination therapy offers excellent treatment efficacy, safety and tolerability. This review focuses on current literature and clinical evidence and their impact regarding NS3/4A protease inhibitors. In addition, pitfalls in treatment from HIV- and HBV-coinfected patients will also be discussed. In the era of DAA treatment, the third-generation pan-genotypic NS3/4A protease inhibitors (mainly grazoprevir, glecaprevir and voxilaprevir) show a high antiviral activity and genetic resistance barrier with cure rates of over 95% when combined with an NS5A inhibitor, irrespectively of baseline resistance associated variants (RASs) being present. These new key components of DAA combination therapy are impressive options to eradicate HCV in the so called difficult-to-treat population (e.g. compensated cirrhosis, end-stage renal disease and patients who failed previous DAA treatment).

Published
2017
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7. Immunogenicity, reactogenicity, and safety of a second booster with BNT162b2 or full-dose mRNA-1273: A randomized VACCELERATE trial in adults aged ≥75 years (EU-COVAT-1-AGED Part B)

Author

Stemler, Jannik, Yeghiazaryan, Lusine, Stephan, Christoph, Mohn, Kristin Greve-Isdahl, Carcas-Sansuan, Antonio-José, Rodriguez, Esperanza Romero, Moltó, José, Mitxeltorena, Itziar Vergara, Welte, Tobias, Zablockienė, Birutė, Akova, Murat, Bethe, Ullrich, Heringer, Sarah, Salmanton-García, Jon, Jeck, Julia, Tischmann, Lea, Zarrouk, Marouan, Cüppers, Arnd, Biehl, Lena M., Grothe, Jan, Mellinghoff, Sibylle C., Nacov, Julia A., Neuhann, Julia M., Sprute, Rosanne, Frías-Iniesta, Jesús, Negi, Riya, Gaillard, Colette, Saini, Gurvin, León, Alejandro García, Mallon, Patrick W.G., Lammens, Christine, Hotterbeekx, An, Loens, Katherine, Malhotra-Kumar, Surbhi, Goossens, Herman, Kumar-Singh, Samir, König, Franz, Posch, Martin, Koehler, Philipp, and Cornely, Oliver A.

Published
2024
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9. Next-generation study databases require FAIR, EHR-integrated, and scalable Electronic Data Capture for medical documentation and decision support

Author

Martin Dugas, Max Blumenstock, Tobias Dittrich, Urs Eisenmann, Stephan Christoph Feder, Fleur Fritz-Kebede, Lucy J. Kessler, Maximilian Klass, Petra Knaup, Christoph U. Lehmann, Angela Merzweiler, Christian Niklas, Thomas M. Pausch, Nelly Zental, and Matthias Ganzinger

Subjects
Computer applications to medicine. Medical informatics, R858-859.7
Abstract

Abstract Structured patient data play a key role in all types of clinical research. They are often collected in study databases for research purposes. In order to describe characteristics of a next-generation study database and assess the feasibility of its implementation a proof-of-concept study in a German university hospital was performed. Key characteristics identified include FAIR access to electronic case report forms (eCRF), regulatory compliant Electronic Data Capture (EDC), an EDC with electronic health record (EHR) integration, scalable EDC for medical documentation, patient generated data, and clinical decision support. In a local case study, we then successfully implemented a next-generation study database for 19 EDC systems (n = 2217 patients) that linked to i.s.h.med (Oracle Cerner) with the local EDC system called OpenEDC. Desiderata of next-generation study databases for patient data were identified from ongoing local clinical study projects in 11 clinical departments at Heidelberg University Hospital, Germany, a major tertiary referral hospital. We compiled and analyzed feature and functionality requests submitted to the OpenEDC team between May 2021 and July 2023. Next-generation study databases are technically and clinically feasible. Further research is needed to evaluate if our approach is feasible in a multi-center setting as well.

Published
2024
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10. Dynamics and durability of HIV-1 neutralization are determined by viral replication

Author

Schommers, Philipp, Kim, Dae Sung, Schlotz, Maike, Kreer, Christoph, Eggeling, Ralf, Hake, Anna, Stecher, Melanie, Park, Juyeon, Radford, Caelan E., Dingens, Adam S., Ercanoglu, Meryem S., Gruell, Henning, Odidika, Stanley, Dahlhaus, Marten, Gieselmann, Lutz, Ahmadov, Elvin, Lawong, Rene Y., Heger, Eva, Knops, Elena, Wyen, Christoph, Kümmerle, Tim, Römer, Katja, Scholten, Stefan, Wolf, Timo, Stephan, Christoph, Suárez, Isabelle, Raju, Nagarajan, Adhikari, Anurag, Esser, Stefan, Streeck, Hendrik, Duerr, Ralf, Nanfack, Aubin J., Zolla-Pazner, Susan, Geldmacher, Christof, Geisenberger, Otto, Kroidl, Arne, William, Wiston, Maganga, Lucas, Ntinginya, Nyanda Elias, Georgiev, Ivelin S., Vehreschild, Jörg J., Hoelscher, Michael, Fätkenheuer, Gerd, Lavinder, Jason J., Bloom, Jesse D., Seaman, Michael S., Lehmann, Clara, Pfeifer, Nico, Georgiou, George, and Klein, Florian

Published
2023
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11. Care interruptions and mortality among adults in Europe and North America

Author

Trickey, Adam, Zhang, Lei, Rentsch, Christopher T., Pantazis, Nikos, Izquierdo, Rebeca, Antinori, Andrea, Leierer, Gisela, Burkholder, Greer, Cavassini, Matthias, Palacio-Vieira, Jorge, Gill, M. John, Teira, Ramon, Stephan, Christoph, Obel, Niels, Vehreschild, Jorg-Janne, Sterling, Timothy R., Van Der Valk, Marc, Bonnet, Fabrice, Crane, Heidi M., Silverberg, Michael J., Ingle, Suzanne M., and Sterne, Jonathan A.C.

Published
2024
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14. Development of a Verification Procedure of Partial Loading on Existing Solid Hydraulic Structures - Probabilistic Assessment for 3D Material Variations

Author

Rüd, Sophie, Müller, Hilmar, Fleischer, Helmut, Stephan, Christoph, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Li, Yun, editor, Hu, Yaan, editor, Rigo, Philippe, editor, Lefler, Francisco Esteban, editor, and Zhao, Gensheng, editor

Published
2023
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15. Monitoring of Hydraulic Structure: Problem and Approach

Author

Kühne, Charly, Stephan, Christoph, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Rizzo, Piervincenzo, editor, and Milazzo, Alberto, editor

Published
2023
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16. Safety and efficacy of doravirine as first-line therapy in adults with HIV-1: week 192 results from the open-label extensions of the DRIVE-FORWARD and DRIVE-AHEAD phase 3 trials

Author

Martins, Marcelo D, Cahn, Pedro E, Lopardo, Gustavo D, Porteiro, Norma, Bloch, Mark Theo, Baker, David Alfred, Roth, Norman, Moore, Richard J, Finlayson, Robert James, McMahon, James, Rieger, Armin, Zoufaly, Alexander, Schmied, Brigitte, Hartl, Sylvia, Zangerle, Robert, Smaill, Fiona, Walmsley, Sharon L, Conway, Brian, Rachlis, Anita, Smith, Graham H R, Perez Cortes, Carlos, Afani, Alejandro, Campos Barker, Maria Isabel E, Chahin Anania, Carolina Eugenia, Reyes, Marcelo J. Wolff, Gerstoft, Jan, Weis, Nina, Laursen, Alex Lund, Molina, Jean-Michel, Yazdanpanah, Yazdan, Cotte, Laurent, Raffi, Francois, Slama, Laurence, Morlat, Philippe, Girard, Pierre-Marie, Katlama, Christine, Rockstroh, Juergen K, Arasteh, Keikawus, Esser, Stefan, Stoehr, Albrecht, Stellbrink, Hans-Juergen, Stoll, Matthias, Schuermann, Dirk, Faetkenheuer, Gerd, Bogner, Johannes Richard, Lutz, Thomas, Baumgarten, Axel, Jaeger, Hans, Wiese, Carmen, Gori, Andrea, Migliorino, Guglielmo Marco, Coltan, Gabriel, Constandis, Felicia, Erscoiu, Simona M, Prisacariu, Liviu-Jany, Rugina, Sorin, Streinu-Cercel, Adrian, Pokrovsky, Vadim V, Zakharova, Natalia, Shuldyakov, Andrey Anatolyevich, Ryamova, Elena Pavlovna, Kulagin, Valeriy Viktorovich, Tsybakova, Olga Aleksandrovna, Orlova-Morozova, Elena, Nagimova, Firaya, Voronin, Evgeniy, Shimonova, Tatiana Evgenyevna, Kozyrev, Oleg Anatolyevich, Orrell, Catherine, Lombaard, Johannes Jurgens, Botes, Margaretha Elizabeth, de Jager, Marleen, Segorb, Joaquin Portilla, Gatell Artigas, Josep Maria, Mallolas Masferrer, Josep, Guillen, Santiago Moreno, Perez Elias, Maria Jesus, Arribas Lopez, Jose R, Puigmal, Eugenia Negredo, Podzamczer Palter, Daniel, Ortega, Frederico Pulido, Garcia, Jesus Troya, de los Santos Gil, Ignacio, Berenguer, Juan, Nelson, Mark Richard, Williams, Ian G, Johnson, Margaret A, Khoo, Saye, Schembri, Gabriel, Clarke, Amanda, Gompels, Mark, Fox, Julie Meriel, Lwanga, Julianne, Taylor, Steven John, Dockrell, David Harold, Kegg, Stephen, Hagins, Debbie P, Osiyemi, Olayemi O, Prelutsky, David James, Ramgopal, Moti N, Scarsella, Anthony J, Dretler, Robin, DeJesus, Edwin, Bettacchi, Christopher J, Sims III, James, Clay, Patrick G, Bellos, Nicholaos C, Thompson, Melanie A, Montero, Jose, McDonald, Cheryl K, Creticos, Catherine, Shamblaw, David, Terrelonge, Antonio E, Valdes, Martin, Tashima, Karen T, Robbins, William J, Elion, Richard A, Goldstein, Deborah, Slim, Jihad, Lalezari, Jacob Paul, Pushkin, Richard, Lalla-Reddy, Sujata N, Win, Sanda S, Ruane, Peter Jerome, Mills, Anthony Martin, Cade, Jerry L, Campo, Rafael, Dietz, Craig A, Hoffman-Terry, Margaret, Blick, Gary, Rubin, David Scott, Mayer, Cynthia, Rondon, Juan Carlos, Cook, Paul P, Daar, Eric, Kumar, Princy N, Swindells, Susan, Castro, Jose Guillermo, Morales-Ramirez, Javier O, Santiago, Lizette, Santana-Bagur, Jorge L, Vandekerckhove, Linos, Florence, Eric, De Wit, Stephane, Derdelinckx, Inge, Vandercam, Bernard, Belkhir, Leila, De Wet, Joseph, Lebouche, Bertrand, Trottier, Benoit, Longpre, Daniele, Szabo, Jason, LeBlanc, Roger P, Jensen, Werner, Gonzalez, Alvaro Rojas, Beltran, Carlos, Sussmann, Otto Alberto, Velez, Juan Diego, Onate, Jose Millan, Nielsen, Henrik, Degen, Olaf, Stephan, Christoph, Arathoon, Eduardo, Lopez, Rudy Manuel, Rojas Alvarado, Evelyn Michelle, Gonzalez Patzan, Luis Demetrio, Meija, Carlos R, Pinzon, Rodolfo, Parchment, Charles, Sthoeger, Zev, Chowers, Michal, Riesenberg, Klaris, Shahar, Eduardo, Levy, Itzchak, Quintero Perez, Nora Patricia, Andrade-Villanueva, Jaime Federico, Crabtree Ramirez, Brenda Eloisa, Rijnders, Bart, den Hollander, Jan G, Handy, Rupert, Morales, Nilo Bonifacio, Hidalgo, Jose Alfredo, Infante, Rosa Mercedes, Matos Prado, Eduardo Demetrio, Campos, Pablo E, Ticona Chaves, Eduardo Romulo, Pinedo, Yvett, Pacheco, Patricia, Maltez, Fernando Manuel, Cunha, Jose, Neves, Isabel, Serrao, Rosario, Melendez-Rivera, Ivan, Mendoza-Rodriguez, Rafael O, Maldonado-Rivera, Sandra, Ortiz-Lasanta, Grisell, Kizhlo, Svetlana, Freud, Hernando Knobel, Moreno, Jose Sanz, Mendez, Francisco Vera, Mohapi, Lerato, Mitha, Essack Aziz, Mahomed, Akbar Anvar, Fouche, Leon Frederik, Kaplan, Richard, Siddique, Naeem, Hoosen, Farzana, Rassool, Mohammed Siddique, Baraldi, Ezio, Calmy, Alexandra, Cavassini, Matthias, Fehr, Jan, Tsai, Hung-Chin, Lin, Hsi-Hsun, Huang, Chun-Kai, Ko, Wen-Chien, Lin, Yu-Hui, Chen, Su-Jung, Hung, Chien-Ching, Avihingsanon, Anchalee, Kiertiburanakul, Sasisopin, Ratanasuwan, Winai, Supparatpinyo, Khuanchai, Chetchotisakd, Ploenchan, Changpradub, Dhitiwat, Orkin, Chloe, Fox, Ashini, Winston, Alan, Ustianowski, Andrew, Yangco, Bienvenido G, Asmuth, David Michael, Vigil, Karen J, Berger, Daniel S, Bhatti, Laveeza, Campbell, Thomas, Casey, Kathleen K, Liu, Edward, Crofoot, Gordon E, Cunningham, Douglas, Feinberg, Judith, Fichtenbaum, Carl, Balamban Felizarta, Franco Antonio, Jefferson, Thomas T, Johnson, Marc Alexander, Lewis, Stanley T, Luque, Amneris E, Novak, Richard M, Sloan, Louis, Sweet, Donna E, Towner, William J, Zane, Ryan, Riedel, David J, Loftus, Richard Anton, Shon, Alyssa So Young, Mogyoros, Miguel, Tebas, Pablo, Scott, Mia Louise, Parenti, David M, Inciarte Portillo, Alexy, Cahn, Pedro, Lombaard, Johannes, Kumar, Sushma, Campbell, Havilland, Wan, Hong, Teal, Valerie, Jin Xu, Zhi, Asante-Appiah, Ernest, Sklar, Peter, Teppler, Hedy, and Lahoulou, Rima

Published
2024
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21. Drug Resistance Spread in 6 Metropolitan Regions, Germany, 2001-20181.

Author

Stecher, Melanie, Chaillon, Antoine, Stephan, Christoph, Knops, Elena, Kohmer, Niko, Lehmann, Clara, Eberle, Josef, Bogner, Johannes, Spinner, Christoph D, Eis-Hübinger, Anna Maria, Wasmuth, Jan-Christian, Schäfer, Guido, Behrens, Georg, Mehta, Sanjay R, Vehreschild, Jörg Janne, and Hoenigl, Martin

Subjects
ART, Germany, HIV transmission, antimicrobial resistance, antiretroviral therapy, mutations, phylogenetic analysis, public health, Microbiology, Clinical Sciences, Medical Microbiology, Public Health and Health Services
Abstract

We analyzed 1,397 HIV-1 pol sequences of antiretroviral therapy-naive patients in a total of 7 university hospitals in Bonn, Cologne, Frankfurt, Hamburg, Hannover, and Munich, Germany. Phylogenetic and network analysis elucidated numerous cases of shared drug resistance mutations among genetically linked patients; K103N was the most frequently shared mutation.

Published
2020

22. Life expectancy after 2015 of adults with HIV on long-term antiretroviral therapy in Europe and North America: a collaborative analysis of cohort studies

Author

Trickey, Adam, Sabin, Caroline A, Burkholder, Greer, Crane, Heidi, d'Arminio Monforte, Antonella, Egger, Matthias, Gill, M John, Grabar, Sophie, Guest, Jodie L, Jarrin, Inma, Lampe, Fiona C, Obel, Niels, Reyes, Juliana M, Stephan, Christoph, Sterling, Timothy R, Teira, Ramon, Touloumi, Giota, Wasmuth, Jan-Christian, Wit, Ferdinand, Wittkop, Linda, Zangerle, Robert, Silverberg, Michael J, Justice, Amy, and Sterne, Jonathan A C

Published
2023
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23. 15 Besondere Patientengruppen

Author

Beutel, Gernot, primary, Lund, Frederike, additional, Weigand, Markus A., additional, Schleenvoigt, Benjamin T., additional, Stephan, Christoph, additional, Schmid, Benedikt, additional, Meybohm, Patrick, additional, and Kranke, Peter, additional

Published
2022
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24. Observational cohort study of rilpivirine (RPV) utilization in Europe

Author

Cozzi-Lepri, Alessandro, Peters, Lars, Pelchen-Matthews, Annegret, Neesgaard, Bastian, De Wit, Stephane, Johansen, Isik Somuncu, Edwards, Simon, Stephan, Christoph, Adamis, Georgios, Staub, Therese, Zagalo, Alexandra, Domingo, Pere, Elbirt, Daniel, Kusejko, Katharina, Brännström, Johanna, Paduta, Dzmitry, Trofimova, Tatyana, Szlavik, Janos, Zilmer, Kai, Losso, Marcello, Van Eygen, Veerle, Pai, Helen, Lundgren, Jens, and Mocroft, Amanda

Published
2022
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26. Effectiveness, safety, and patient‐reported outcomes of emtricitabine/tenofovir alafenamide‐based regimens for the treatment of HIV‐1 infection: Final 24‐month results from the prospective German TAFNES cohort study.

Author

Stephan, Christoph, Spinner, Christoph D., Rieke, Ansgar, Christensen, Stefan, Mauss, Stefan, Schreiber, Sandra, Albuquerque, Boris, Heinzkill, Marion, Ramroth, Heribert, and Stellbrink, Hans‐Jürgen

Subjects
*DRUG side effects, *PATIENT satisfaction, *DISEASE risk factors, *CHRONIC kidney failure, *ANTIRETROVIRAL agents
Abstract

Background Methods Results Conclusion Tenofovir alafenamide (TAF) was introduced in the European Union in 2015 as a novel prodrug of tenofovir showing similar efficacy in clinical trials and a more favorable safety profile than tenofovir disoproxil fumarate (TDF). The German TAFNES cohort study (2016–2019) was conducted to generate real‐world evidence.Treatment‐naïve (TN) and treatment‐experienced (TE) people with HIV (PWH) receiving elvitegravir/cobicistat/emtricitabine/TAF (E/C/F/TAF), rilpivirine/F/TAF (R/F/TAF) or F/TAF + 3rd agent were included. Month (M) 24 outcomes included virologic effectiveness (HIV RNA <50 copies/mL), treatment persistence, adverse drug reactions (ADRs) and patient‐reported outcomes, using the HIV Symptom Index (HIV‐SI), 36‐Item Short Form Health Survey (SF‐36) and HIV Treatment Satisfaction (HIVTSQ) questionnaires.The study included 767 PWH (92% men, median age 46 years; 301 TN, 466 TE; E/C/F/TAF [n = 318], R/F/TAF [n = 192], F/TAF + 3rd agent [n = 257]). Among TN, 35% had late HIV diagnosis (CD4 < 350/μL and/or AIDS). Of TE, 95% were on suppressive antiretroviral therapy (ART) before switching. D:A:D (Data Collection on Adverse Effects of Anti‐HIV Drugs) 5‐year risks for chronic kidney disease were high for about 1 in 10 TN and 4 in 10 TE. Overall treatment persistence at M24 was 81% (E/C/F/TAF: 88%; R/F/TAF: 86%; F/TAF + 3rd agent: 70%, with ART simplification of multiple‐tablet regimens in 13%). M24 viral suppression (missing = excluded) was 96% (479/501). Discontinuations due to virologic failure or ADRs were rare, 2% (12/767) and 4% (30/767), respectively. HIV‐SI and SF‐36 summary scores improved in TN; HIVTSQ change scores showed an improvement in treatment satisfaction in TE.Real‐world data confirmed a favorable safety profile and high virologic effectiveness with high treatment satisfaction on F/TAF‐based ART. [ABSTRACT FROM AUTHOR]

Published
2024
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27. Therapeutic Drug Monitoring of Long-Acting Rilpivirine and Cabotegravir for Treatment of HIV-1 Infection—A Case Series of Five Patients With One Virologic Failure After Development of Two-Class Resistance.

Author

Gerstenberg, Jacob, Klinker, Hartwig, Baier, Michael, Braun, Amrei von, Seybold, Ulrich, Helbig, Carlotta, Däumer, Martin, Korn, Klaus, Stephan, Christoph, and Schleenvoigt, Benjamin T

Subjects
DRUG monitoring, HIV
Abstract

Virologic failure of long-acting rilpivirine/cabotegravir is rare but may result in severely limited treatment options. Known risk factors cannot predict all cases. Therapeutic drug monitoring (TDM) may help identify patients at risk, but reliable thresholds are missing. We report retrospective TDM in a cohort of 5 patients, including 1 virological failure. [ABSTRACT FROM AUTHOR]

Published
2024
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29. Plasma-neutral interactions in the lower thermosphere-ionosphere: The need for in situ measurements to address focused questions

Author

Theodoros Sarris, Minna Palmroth, Anita Aikio, Stephan Christoph Buchert, James Clemmons, Mark Clilverd, Iannis Dandouras, Eelco Doornbos, Lindsay Victoria Goodwin, Maxime Grandin, Roderick Heelis, Nickolay Ivchenko, Therese Moretto-Jørgensen, Guram Kervalishvili, David Knudsen, Han-Li Liu, Gang Lu, David M. Malaspina, Octav Marghitu, Astrid Maute, Wojciech J. Miloch, Nils Olsen, Robert Pfaff, Claudia Stolle, Elsayed Talaat, Jeffrey Thayer, Stelios Tourgaidis, Pekka T. Verronen, and Masatoshi Yamauchi

Subjects
lower thermosphere ionosphere, plasma neutral interactions, in situ measurements, decadal survey, atmosphere space transition region, altitudes below 200 km, Astronomy, QB1-991, Geophysics. Cosmic physics, QC801-809
Abstract

The lower thermosphere-ionosphere (LTI) is a key transition region between Earth’s atmosphere and space. Interactions between ions and neutrals maximize within the LTI and in particular at altitudes from 100 to 200 km, which is the least visited region of the near-Earth environment. The lack of in situ co-temporal and co-spatial measurements of all relevant parameters and their elusiveness to most remote-sensing methods means that the complex interactions between its neutral and charged constituents remain poorly characterized to this date. This lack of measurements, together with the ambiguity in the quantification of key processes in the 100–200 km altitude range affect current modeling efforts to expand atmospheric models upward to include the LTI and limit current space weather prediction capabilities. We present focused questions in the LTI that are related to the complex interactions between its neutral and charged constituents. These questions concern core physical processes that govern the energetics, dynamics, and chemistry of the LTI and need to be addressed as fundamental and long-standing questions in this critically unexplored boundary region. We also outline the range of in situ measurements that are needed to unambiguously quantify key LTI processes within this region, and present elements of an in situ concept based on past proposed mission concepts.

Published
2023
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30. Daedalus MASE (mission assessment through simulation exercise): A toolset for analysis of in situ missions and for processing global circulation model outputs in the lower thermosphere-ionosphere

Author

Theodore E. Sarris, Stelios Tourgaidis, Panagiotis Pirnaris, Dimitris Baloukidis, Konstantinos Papadakis, Christos Psychalas, Stephan Christoph Buchert, Eelco Doornbos, Mark A. Clilverd, Pekka T. Verronen, David Malaspina, Narghes Ahmadi, Iannis Dandouras, Anna Kotova, Wojciech J. Miloch, David Knudsen, Nils Olsen, Octav Marghitu, Tomoko Matsuo, Gang Lu, Aurélie Marchaudon, Alex Hoffmann, Dulce Lajas, Anja Strømme, Matthew Taylor, Anita Aikio, Minna Palmroth, Roderick Heelis, Nickolay Ivchenko, Claudia Stolle, Guram Kervalishvili, Therese Moretto-Jørgensen, Robert Pfaff, Christian Siemes, Pieter Visser, Jose van den Ijssel, Han-Li Liu, Ingmar Sandberg, Constantinos Papadimitriou, Joachim Vogt, Adrian Blagau, and Nele Stachlys

Subjects
lower thermosphere ionosphere, in situ measurements, global circulation model, daedalus mission, daedalus MASE, GCM, Astronomy, QB1-991, Geophysics. Cosmic physics, QC801-809
Abstract

Daedalus MASE (Mission Assessment through Simulation Exercise) is an open-source package of scientific analysis tools aimed at research in the Lower Thermosphere-Ionosphere (LTI). It was created with the purpose to assess the performance and demonstrate closure of the mission objectives of Daedalus, a mission concept targeting to perform in-situ measurements in the LTI. However, through its successful usage as a mission-simulator toolset, Daedalus MASE has evolved to encompass numerous capabilities related to LTI science and modeling. Inputs are geophysical observables in the LTI, which can be obtained either through in-situ measurements from spacecraft and rockets, or through Global Circulation Models (GCM). These include ion, neutral and electron densities, ion and neutral composition, ion, electron and neutral temperatures, ion drifts, neutral winds, electric field, and magnetic field. In the examples presented, these geophysical observables are obtained through NCAR’s Thermosphere-Ionosphere-Electrodynamics General Circulation Model. Capabilities of Daedalus MASE include: 1) Calculations of products that are derived from the above geophysical observables, such as Joule heating, energy transfer rates between species, electrical currents, electrical conductivity, ion-neutral collision frequencies between all combinations of species, as well as height-integrations of derived products. 2) Calculation and cross-comparison of collision frequencies and estimates of the effect of using different models of collision frequencies into derived products. 3) Calculation of the uncertainties of derived products based on the uncertainties of the geophysical observables, due to instrument errors or to uncertainties in measurement techniques. 4) Routines for the along-orbit interpolation within gridded datasets of GCMs. 5) Routines for the calculation of the global coverage of an in situ mission in regions of interest and for various conditions of solar and geomagnetic activity. 6) Calculations of the statistical significance of obtaining the primary and derived products throughout an in situ mission’s lifetime. 7) Routines for the visualization of 3D datasets of GCMs and of measurements along orbit. Daedalus MASE code is accompanied by a set of Jupyter Notebooks, incorporating all required theory, references, codes and plotting in a user-friendly environment. Daedalus MASE is developed and maintained at the Department for Electrical and Computer Engineering of the Democritus University of Thrace, with key contributions from several partner institutions.

Published
2023
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33. Contemporary antiretrovirals and body-mass index: a prospective study of the RESPOND cohort consortium

Author

Bansi-Matharu, Loveleen, Phillips, Andrew, Oprea, Cristiana, Grabmeier-Pfistershammer, Katharina, Günthard, Huldrych F, De Wit, Stephane, Guaraldi, Giovanni, Vehreschild, Jorg J, Wit, Ferdinand, Law, Matthew, Wasmuth, Jan-Christian, Chkhartishvili, Nikoloz, d'Arminio Monforte, Antonella, Fontas, Eric, Vesterbacka, Jan, Miro, Jose M, Castagna, Antonella, Stephan, Christoph, Llibre, Josep M, Neesgaard, Bastian, Greenberg, Lauren, Smith, Colette, Kirk, Ole, Duvivier, Claudine, Dragovic, Gordana, Lundgren, Jens, Dedes, Nikos, Knudsen, Andreas, Gallant, Joel, Vannappagari, Vani, Peters, Lars, Elbirt, Daniel, Sarcletti, Mario, Braun, Dominique L, Necsoi, Coca, Mussini, Cristina, Muccini, Camilla, Bolokadze, Natalie, Hoy, Jennifer, Mocroft, Amanda, and Ryom, Lene

Published
2021
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34. Shotgun metagenomic sequencing analysis of ocular surface microbiome in Singapore residents with mild dry eye

Author

Louis Tong, Florentin Constancias, Aihua Hou, Song Lin Chua, Daniela I. Drautz-Moses, Stephan Christoph Schuster, Liang Yang, Rohan B. H. Williams, and Staffan Kjelleberg

Subjects
human microbiome, inflammation, ocular disease, dry eye, metagenomics, Medicine (General), R5-920
Abstract

The ocular surface microbiome has implications for ocular surface inflammation and immunology. Previous shotgun metagenomics analyses were performed in China, showing results that differed according to environment and age. Patients with Sjogren’s syndrome were reported to have altered conjunctival microbiome, but such studies have not been done in milder dry eye. The aim of this study is to describe the conjunctival microbiome in people with mild dry eye in Singapore. Samples were collected from 14 participants with mild dry eye and 10 age-matched comparison participants recruited from Singapore National Eye Centre (SNEC) clinics. Shotgun metagenomic sequencing analysis was employed to evaluate the conjunctival microbiome composition. Proteobacteria formed the predominant phylum in the conjunctiva. As in a study from a coastal city in China, Achromobacter spp. was numerically most abundant. Compared to age-matched controls, the conjunctival microbial composition in mild dry eye was similar. Several microorganisms, including Streptococcus spp. increased in representation with age, and the abundance of Staphylococcus correlated with Schirmer readings. In addition, when cultured corneal epithelial cells were exposed to three strains of Achromobacter xylosoxidans, cytokines such as TNF-α and IL-6 were upregulated in the cell lysates and supernatants. Ourresults suggest that age is an important factor that affects composition of the conjunctival microbiome, and relative abundance of specific microorganism may vary according to the environment of the human host.

Published
2022
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35. No need for secondary Pneumocystis jirovecii pneumonia prophylaxis in adult people living with HIV from Europe on ART with suppressed viraemia and a CD4 cell count greater than 100 cells/[micro]L

Author

Atkinson, Andrew, Miro, Jose M., Mocroft, Amanda, Reiss, Peter, Kirk, Ole, Morlat, Philippe, Ghosn, Jade, Stephan, Christoph, Mussini, Cristina, Antoniadou, Anastasia, Doerholt, Katja, Girardi, Enrico, Wit, Stephane De, Kraus, David, Zwahlen, Marcel, and Furrer, Hansjakob

Subjects
Antiviral agents -- Patient outcomes, Viremia -- Patient outcomes, Pneumocystis carinii pneumonia -- Prevention -- Risk factors -- Statistics, CD4 lymphocytes -- Health aspects, HIV patients -- Drug therapy -- Statistics, Health
Abstract

Introduction: Since the beginning of the HIV epidemic in resource-rich countries, Pneumocystis jirovecii pneumonia (PjP) is one of the most frequent opportunistic AIDS-defining infections. The Collaboration of ObservationalHIV EpidemiologicalResearch Europe (COHERE) has shown that primary Pneumocystis jirovecii Pneumonia (PjP) prophylaxis can be safely withdrawn in patients with CD4 counts of 100 to 200 cells/[micro]L if plasma HIV-RNA is suppressed on combination antiretroviraltherapy. Whether this holds true for secondary prophylaxis is not known, and this has proved difficult to determine due to the much lower population at risk. Methods: We estimated the incidence of secondary PjP by including patient data collected from 1998 to 2015 from the COHERE cohort collaboration according to time-updated CD4 counts, HIV-RNA and use of PjP prophylaxis in persons >16 years of age. We fitted a Poisson generalized additive modelin which the smoothed effect of CD4 was modelled by a restricted cubic spline, and HIV-RNA was stratified as low (10,000copies/mL). Results: There were 373 recurrences of PjP during 74,295 person-years (py) in 10,476 patients. The PjP incidence in the different plasma HIV-RNA strata differed significantly and was lowest in the low stratum. For patients off prophylaxis with CD4 counts between 100 and 200 cells/[micro]L and HIV-RNA below 400 copies/mL, the incidence of recurrent PjP was 3.9 (95% CI: 2.0 to 5.8) per 1000 py, not significantly different from patients on prophylaxis in the same stratum (1.9, 95% CI: 0.1 to 3.7). Conclusions: HIV viraemia importantly affects the risk of recurrent PjP. In virologically suppressed patients on ART with CD4 counts of 100 to 200/[micro]L, the incidence of PjP off prophylaxis is below 10/1000 py. Secondary PjP prophylaxis may be safely withheld in such patients. While European guidelines recommend discontinuing secondary PjP prophylaxis only if CD4 counts rise above 200 cells/mL, the latest US Guidelines consider secondary prophylaxis discontinuation even in patients with a CD4 count above 100 cells/[micro]L and suppressed viral load. Our results strengthen and support this US recommendation. Keywords: opportunistic infections; Pneumocystis jirovecii pneumonia; prophylaxis, 1 INTRODUCTION Since the beginning of the HIV epidemic in resource-rich countries, Pneumocystis jirovecii pneumonia (PjP) is one of the most frequent opportunistic AIDS-defining infections [1]. PjP occurs predominantly in [...]

Published
2021
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36. Comparison of Kaposi Sarcoma Risk in Human Immunodeficiency Virus-Positive Adults Across 5 Continents: A Multiregional Multicohort Study

Author

Judd, Ali, Zangerle, Robert, Touloumi, Giota, Warszawski, Josiane, Meyer, Laurence, Dabis, François, Krause, Murielle Mary, Ghosn, Jade, Leport, Catherine, Wittkop, Linda, Reiss, Peter, Wit, Ferdinand, Prins, Maria, Bucher, Heiner, Gibb, Diana, Fätkenheuer, Gerd, Julia, Del Amo, Obel, Niels, Thorne, Claire, Mocroft, Amanda, Kirk, Ole, Stephan, Christoph, Pérez-Hoyos, Santiago, Hamouda, Osamah, Bartmeyer, Barbara, Chkhartishvili, Nikoloz, Noguera-Julian, Antoni, Antinori, Andrea, Monforte, Antonella d’Arminio, Brockmeyer, Norbert, Prieto, Luis, Conejo, Pablo Rojo, Soriano-Arandes, Antoni, Battegay, Manuel, Kouyos, Roger, Mussini, Cristina, Tookey, Pat, Casabona, Jordi, Miró, Jose M, Castagna, Antonella, Konopnick, Deborah, Goetghebuer, Tessa, Sönnerborg, Anders, Quiros-Roldan, Eugenia, Sabin, Caroline, Teira, Ramon, Garrido, Myriam, Haerry, David, de Wit, Stéphane, Costagliola, Dominique, d’Arminio-Monforte, Antonella, del Amo, Julia, Raben, Dorthe, Chêne, Geneviève, Rojo, Conejo Pablo, Barger, Diana, Schwimmer, Christine, Termote, Monique, Campbell, Maria, Frederiksen, Casper M, Friis-Møller, Nina, Kjaer, Jesper, Brandt, Rikke Salbøl, Berenguer, Juan, Bohlius, Julia, Bouteloup, Vincent, Cozzi-Lepri, Alessandro, Davies, Mary-Anne, Dorrucci, Maria, Dunn, David, Egger, Matthias, Furrer, Hansjakob, Grabar, Sophie, Guiguet, Marguerite, Lambotte, Olivier, Leroy, Valériane, Lodi, Sara, Matheron, Sophie, Miro, Jose M, Monge, Susana, Nakagawa, Fumiyo, Paredes, Roger, Phillips, Andrew, Puoti, Massimo, Rohner, Eliane, and Schomaker, Michael

Subjects
Biomedical and Clinical Sciences, Clinical Sciences, Sexually Transmitted Infections, Rare Diseases, Emerging Infectious Diseases, Infectious Diseases, HIV/AIDS, Infection, Adolescent, Adult, Anti-Retroviral Agents, CD4 Lymphocyte Count, Cohort Studies, Female, HIV Infections, HIV-1, Humans, Male, Middle Aged, Risk Factors, Sarcoma, Kaposi, Viral Load, Young Adult, AIDS-defining Cancer Project Working Group for IeDEA and COHERE in EuroCoord, HIV, Kaposi sarcoma, antiretroviral therapy, cohort study, Biological Sciences, Medical and Health Sciences, Microbiology, Clinical sciences
Abstract

BackgroundWe compared Kaposi sarcoma (KS) risk in adults who started antiretroviral therapy (ART) across the Asia-Pacific, South Africa, Europe, Latin, and North America.MethodsWe included cohort data of human immunodeficiency virus (HIV)-positive adults who started ART after 1995 within the framework of 2 large collaborations of observational HIV cohorts. We present incidence rates and adjusted hazard ratios (aHRs).ResultsWe included 208140 patients from 57 countries. Over a period of 1066572 person-years, 2046 KS cases were diagnosed. KS incidence rates per 100000 person-years were 52 in the Asia-Pacific and ranged between 180 and 280 in the other regions. KS risk was 5 times higher in South African women (aHR, 4.56; 95% confidence intervals [CI], 2.73-7.62) than in their European counterparts, and 2 times higher in South African men (2.21; 1.34-3.63). In Europe, Latin, and North America KS risk was 6 times higher in men who have sex with men (aHR, 5.95; 95% CI, 5.09-6.96) than in women. Comparing patients with current CD4 cell counts ≥700 cells/µL with those whose counts were

Published
2017

37. Using observational data to emulate a randomized trial of dynamic treatment-switching strategies: an application to antiretroviral therapy

Author

Cain, Lauren E, Saag, Michael S, Petersen, Maya, May, Margaret T, Ingle, Suzanne M, Logan, Roger, Robins, James M, Abgrall, Sophie, Shepherd, Bryan E, Deeks, Steven G, Gill, M John, Touloumi, Giota, Vourli, Georgia, Dabis, François, Vandenhende, Marie-Anne, Reiss, Peter, van Sighem, Ard, Samji, Hasina, Hogg, Robert S, Rybniker, Jan, Sabin, Caroline A, Jose, Sophie, del Amo, Julia, Moreno, Santiago, Rodríguez, Benigno, Cozzi-Lepri, Alessandro, Boswell, Stephen L, Stephan, Christoph, Pérez-Hoyos, Santiago, Jarrin, Inma, Guest, Jodie L, Monforte, Antonella D’Arminio, Antinori, Andrea, Moore, Richard, Campbell, Colin NJ, Casabona, Jordi, Meyer, Laurence, Seng, Rémonie, Phillips, Andrew N, Bucher, Heiner C, Egger, Matthias, Mugavero, Michael J, Haubrich, Richard, Geng, Elvin H, Olson, Ashley, Eron, Joseph J, Napravnik, Sonia, Kitahata, Mari M, Van Rompaey, Stephen E, Teira, Ramón, Justice, Amy C, Tate, Janet P, Costagliola, Dominique, Sterne, Jonathan AC, Hernán, Miguel A, and Systems, and the HIV-CAUSAL Collaboration on behalf of the Antiretroviral Therapy Cohort Collaboration the Centers for AIDS Research Network of Integrated Clinical

Subjects
Epidemiology, Health Sciences, Clinical Trials and Supportive Activities, Infectious Diseases, Sexually Transmitted Infections, HIV/AIDS, Clinical Research, Evaluation of treatments and therapeutic interventions, 6.1 Pharmaceuticals, Infection, Good Health and Well Being, Adult, Anti-HIV Agents, CD4 Lymphocyte Count, Female, HIV Infections, HIV-1, Humans, Male, Middle Aged, Observational Studies as Topic, Randomized Controlled Trials as Topic, Survival Analysis, United Kingdom, Viral Load, HIV, antiretroviral therapy, inverse-probability weighting, observational studies, mortality, dynamic strategies, Antiretroviral Therapy Cohort Collaboration, the Centers for AIDS Research Network of Integrated Clinical Systems, and the HIV-CAUSAL Collaboration, Statistics, Public Health and Health Services, Public health
Abstract

BackgroundWhen a clinical treatment fails or shows suboptimal results, the question of when to switch to another treatment arises. Treatment switching strategies are often dynamic because the time of switching depends on the evolution of an individual's time-varying covariates. Dynamic strategies can be directly compared in randomized trials. For example, HIV-infected individuals receiving antiretroviral therapy could be randomized to switching therapy within 90 days of HIV-1 RNA crossing above a threshold of either 400 copies/ml (tight-control strategy) or 1000 copies/ml (loose-control strategy).MethodsWe review an approach to emulate a randomized trial of dynamic switching strategies using observational data from the Antiretroviral Therapy Cohort Collaboration, the Centers for AIDS Research Network of Integrated Clinical Systems and the HIV-CAUSAL Collaboration. We estimated the comparative effect of tight-control vs. loose-control strategies on death and AIDS or death via inverse-probability weighting.ResultsOf 43 803 individuals who initiated an eligible antiretroviral therapy regimen in 2002 or later, 2001 met the baseline inclusion criteria for the mortality analysis and 1641 for the AIDS or death analysis. There were 21 deaths and 33 AIDS or death events in the tight-control group, and 28 deaths and 41 AIDS or death events in the loose-control group. Compared with tight control, the adjusted hazard ratios (95% confidence interval) for loose control were 1.10 (0.73, 1.66) for death, and 1.04 (0.86, 1.27) for AIDS or death.ConclusionsAlthough our effective sample sizes were small and our estimates imprecise, the described methodological approach can serve as an example for future analyses.

Published
2016

38. Switching to dolutegravir plus rilpivirine versus maintaining current antiretroviral therapy regimen in virologically suppressed people with HIV-1 and the Lys103Asn (K103N) mutation: 48-week results from a randomised, open-label pilot clinical trial

Author

Moyle, Graeme, Assoumou, Lambert, de Castro, Nathalie, Post, Frank A, Curran, Adrian, Rusconi, Stefano, De Wit, Stephane, Stephan, Christoph, Raffi, François, Johnson, Margaret, Masia, Mar, Vera, Jaime, Jones, Bryn, Grove, Richard, Fletcher, Carl, Duffy, Annie, Morris, Kellie, Pozniak, Anton, Moyle, Graeme, de Castro, Nathalie, Post, Frank, Curran, Adrian, Rusconi, Stefano, De Wit, Stephane, Stephan, Christoph, Raffi, François, Johnson, Margaret, Masia, Mar, Vera, Jaime, Winston, Alan, Kegg, Stephen, Waters, Laura, Orkin, Chole, Ustianowski, Andrew, Reeves, Iain, Leen, Clifford, Perry, Meghan, Portilla, Joaquin, Blanco, Jose Luis, Montejaro, Rocio, Domingo, Pere, Molina, Jean Michel, Katlama, Christine, Morlat, Philippe, Kenyon, Christopher, Puoti, Massimo, Rizzardini, Giuliano, Castagna, Antonella, Castelli, Francesco, Giacomelli, Andrea, Rockstroh, Jürgen, Esser, Stefan, Hoffmann, Christian, and Mallon, Patrick

Abstract

The combination of dolutegravir plus rilpivirine has been studied in people with virologically suppressed HIV with no previous history of treatment failure or resistance. We investigated the potential to maintain viral suppression with dolutegravir plus rilpivirine in people with Lys103Asn mutations whose HIV was previously managed with other treatment regimens.

Published
2024
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40. Noncommutative Geometry in the LHC-Era

Author

Stephan, Christoph A.

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Theory
Abstract

Noncommutative geometry allows to unify the basic building blocks of particle physics, Yang-Mills-Higgs theory and General relativity, into a single geometrical framework. The resulting effective theory constrains the couplings of the particle model and reduces the number of degrees of freedom. After briefly introducing the basic ideas of noncommutative geometry, I will present its predictions for the Standard Model and the few known models beyond the Standard Model. Most of these models, including the Standard Model, are now ruled out by LHC data. But interesting extensions of the Standard Model which agree with the presumed Standard Model Scalar mass and predict new particles are still very much alive and await further experimental data., Comment: Submitted to the Proceedings of he XLVIIIth Rencontres de Moriond EW session

Published
2013

41. A Dark Sector Extension of the Almost-Commutative Standard Model

Author

Stephan, Christoph A.

Subjects
High Energy Physics - Theory, High Energy Physics - Phenomenology
Abstract

We consider an extension of the Standard Model within the frame work of Noncommutative Geometry. The model is based on an older model [St09] which extends the Standard Model by new fermions, a new U(1)-gauge group and, crucially, a new scalar field which couples to the Higgs field. This new scalar field allows to lower the mass of the Higgs mass from ~170 GeV, as predicted by the Spectral Action for the Standard Model, to a value of 120-130 GeV. The short-coming of the previous model lay in its inability to meet all the constraints on the gauge couplings implied by the Spectral Action. These shortcomings are cured in the present model which also features a "dark sector" containing fermions and scalar particles.

Published
2013
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42. HIV-Infektion

Author

Haberl, Annette, primary, Lehmann, Clara, additional, Malin, Jakob J., additional, Rößler, Steve, additional, Schleenvoigt, Benjamin T., additional, Spinner, Christoph D., additional, and Stephan, Christoph, additional

Published
2021
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43. Chiral Asymmetry and the Spectral Action

Author

Pfaeffle, Frank and Stephan, Christoph A.

Subjects
Mathematical Physics, General Relativity and Quantum Cosmology
Abstract

We consider orthogonal connections with arbitrary torsion on compact Riemannian manifolds. For the induced Dirac operators, twisted Dirac operators and Dirac operators of Chamseddine-Connes type we compute the spectral action. In addition to the Einstein-Hilbert action and the bosonic part of the Standard Model Lagrangian we find the Holst term from Loop Quantum Gravity, a coupling of the Holst term to the scalar curvature and a prediction for the value of the Barbero-Immirzi parameter.

Published
2012
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44. The Holst Action by the Spectral Action Principle

Author

Pfaeffle, Frank and Stephan, Christoph A.

Subjects
Mathematical Physics, General Relativity and Quantum Cosmology
Abstract

We investigate the Holst action for closed Riemannian 4-manifolds with orthogonal connections. For connections whose torsion has zero Cartan type component we show that the Holst action can be recovered from the heat asymptotics for the natural Dirac operator acting on left-handed spinor fields., Comment: We correct a sign mistake in Proposition 2.3. As a consequence the main result (Theorem 3.4) becomes more natural

Published
2011
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45. On Gravity, Torsion and the Spectral Action Principle

Author

Pfaeffle, Frank and Stephan, Christoph A.

Subjects
Mathematical Physics
Abstract

We consider compact Riemannian spin manifolds without boundary equipped with orthogonal connections. We investigate the induced Dirac operators and the associated commutative spectral triples. In case of dimension four and totally anti-symmetric torsion we compute the Chamseddine-Connes spectral action, deduce the equations of motions and discuss critical points., Comment: minor modifications, some further typos fixed

Published
2011

46. The Spectral Action for Dirac Operators with skew-symmetric Torsion

Author

Hanisch, Florian, Pfaeffle, Frank, and Stephan, Christoph A.

Subjects
High Energy Physics - Theory, Mathematical Physics
Abstract

We derive a formula for the gravitational part of the spectral action for Dirac operators on 4-dimensional manifolds with totally anti-symmetric torsion. We find that the torsion becomes dynamical and couples to the traceless part of the Riemann curvature tensor. Finally we deduce the Lagrangian for the Standard Model of particle physics in presence of torsion from the Chamseddine-Connes Dirac operator., Comment: Longer introduction and conclusion added

Published
2009
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47. Beyond the Standard Model: A Noncommutative Approach

Author

Stephan, Christoph A.

Subjects
High Energy Physics - Phenomenology
Abstract

During the last two decades Alain Connes developed Noncommutative Geometry (NCG), which allows to unify two of the basic theories of modern physics: General Relativity (GR) and the Standard Model (SM) of Particle Physics as classical field theories. In the noncommutative framework the Higgs boson, which had previously to be put in by hand, and many of the ad hoc features of the standard model appear in a natural way. The aim of this presentation is to motivate this unification from basic physical principles and to give a flavour of its derivation. One basic prediction of the noncommutative approach to the SM is that the mass of the Higgs Boson should be of the order of 170 GeV if one assumes the Big Desert. This mass range is with reasonable probability excluded by the Tevatron and therefore it is interesting to investigate models beyond the SM that are compatible with NCG. Going beyond the SM is highly non-trivial within the NCG approach but possible extensions have been found and provide for phenomenologically interesting models. We will present in this article a short introduction into the NCG framework and describe one of these extensions of the SM. This model contains new scalar bosons (and fermions) which constitute a second Higgs-like sector mixing with theordinary Higgs sector and thus considerably modifying the mass eigenvalues., Comment: To be published in the Proceedings of the XLIVth Rencontres de Moriond: Electroweak Interactions and Unified Theories (La Thuile, Italy, 7-14 March 2009)

Published
2009

48. The Inverse Seesaw Mechanism in Noncommutative Geometry

Author

Stephan, Christoph A.

Subjects
High Energy Physics - Theory, High Energy Physics - Phenomenology
Abstract

In this publication we will implement the inverse Seesaw mechanism into the noncommutative framework on the basis of the AC-extension of the Standard Model. The main difference to the classical AC model is the chiral nature of the AC fermions with respect to a U(1) extension of the Standard Model gauge group. It is this extension which allows us to couple the right-handed neutrinos via a gauge invariant mass term to left-handed A-particles. The natural scale of these gauge invariant masses is of the order of 10^17 GeV while the Dirac masses of the neutrino and the AC-particles are generated dynamically and are therefore much smaller (ca. 1 GeV to 10^6 GeV). From this configuration a working inverse Seesaw mechanism for the neutrinos is obtained.

Published
2009
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49. New Scalar Fields in Noncommutative Geometry

Author

Stephan, Christoph A.

Subjects
High Energy Physics - Theory, High Energy Physics - Phenomenology
Abstract

In this publication we present an extension of the Standard Model within the framework of Connes' noncommutative geometry [1]. The model presented here is based on a minimal spectral triple [7] which contains the Standard Model particles, new vectorlike fermions and a new U(1) gauge subgroup. Additionally a new complex scalar field appears that couples to the right-handed neutrino, the new fermions and the standard Higgs particle. The bosonic part of the action is given by the spectral action [1] which also determines relations among the gauge couplings, the quartic scalar couplings and the Yukawa couplings at a cut-off energy of ca. 10^(17) GeV. We investigate the renormalisation group flow of these relations. The low energy behaviour allows to constrain the Higgs mass, the mass of the new scalar and the mixing between these two scalar fields., Comment: Missing left-hand side of eq. (21) added. Some typos and normalisations in section 3 and 5.2 corrected

Published
2009
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50. On a Classification of Irreducible Almost-Commutative Geometries V

Author

Jureit, Jan-Hendrik and Stephan, Christoph A.

Subjects
High Energy Physics - Theory
Abstract

We extend a classification of irreducible, almost-commutative geometries whose spectral action is dynamically non-degenerate, to internal algebras that have six simple summands. We find essentially four particle models: An extension of the standard model by a new species of fermions with vectorlike coupling to the gauge group and gauge invariant masses, two versions of the electro-strong model and a variety of the electro-strong model with Higgs mechanism.

Published
2009
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