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1. Harmonizing tau positron emission tomography in Alzheimer's disease: The CenTauR scale and the joint propagation model

Author

Leuzy, Antoine, Raket, Lars Lau, Villemagne, Victor L, Klein, Gregory, Tonietto, Matteo, Olafson, Emily, Baker, Suzanne, Saad, Ziad S, Bullich, Santiago, Lopresti, Brian, Bohorquez, Sandra Sanabria, Boada, Mercè, Betthauser, Tobey J, Charil, Arnaud, Collins, Emily C, Collins, Jessica A, Cullen, Nicholas, Gunn, Roger N, Higuchi, Makoto, Hostetler, Eric, Hutchison, R Matthew, Iaccarino, Leonardo, Insel, Philip S, Irizarry, Michael C, Jack, Clifford R, Jagust, William J, Johnson, Keith A, Johnson, Sterling C, Karten, Yashmin, Marquié, Marta, Mathotaarachchi, Sulantha, Mintun, Mark A, Ossenkoppele, Rik, Pappas, Ioannis, Petersen, Ronald C, Rabinovici, Gil D, Rosa‐Neto, Pedro, Schwarz, Christopher G, Smith, Ruben, Stephens, Andrew W, Whittington, Alex, Carrillo, Maria C, Pontecorvo, Michael J, Haeberlein, Samantha Budd, Dunn, Billy, Kolb, Hartmuth C, Sivakumaran, Sudhir, Rowe, Christopher C, Hansson, Oskar, and Doré, Vincent

Subjects
Biological Psychology, Psychology, Brain Disorders, Aging, Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD), Neurosciences, Dementia, Bioengineering, Biomedical Imaging, Alzheimer's Disease, Neurodegenerative, Acquired Cognitive Impairment, Neurological, Alzheimer Disease, Humans, Positron-Emission Tomography, tau Proteins, Brain, Male, Female, Aged, Cohort Studies, Radiopharmaceuticals, Models, Statistical, [F-18]Flortaucipir, [F-18]RO948, [F-18]MK-6240, [F-18]GTP1, [F-18]PI-2620, Alzheimer's disease, C-Path, CenTauR, Centiloid, CPAD, head-to-head, Imaging, PET, standardization, tau, C‐Path, [18F]Flortaucipir, [18F]GTP1, [18F]MK‐6240, [18F]PI‐2620, [18F]RO948, head‐to‐head, Clinical Sciences, Geriatrics, Clinical sciences, Biological psychology
Abstract

IntroductionTau-positron emission tomography (PET) outcome data of patients with Alzheimer's disease (AD) cannot currently be meaningfully compared or combined when different tracers are used due to differences in tracer properties, instrumentation, and methods of analysis.MethodsUsing head-to-head data from five cohorts with tau PET radiotracers designed to target tau deposition in AD, we tested a joint propagation model (JPM) to harmonize quantification (units termed "CenTauR" [CTR]). JPM is a statistical model that simultaneously models the relationships between head-to-head and anchor point data. JPM was compared to a linear regression approach analogous to the one used in the amyloid PET Centiloid scale.ResultsA strong linear relationship was observed between CTR values across brain regions. Using the JPM approach, CTR estimates were similar to, but more accurate than, those derived using the linear regression approach.DiscussionPreliminary findings using the JPM support the development and adoption of a universal scale for tau-PET quantification.HighlightsTested a novel joint propagation model (JPM) to harmonize quantification of tau PET. Units of common scale are termed "CenTauRs". Tested a Centiloid-like linear regression approach. Using five cohorts with head-to-head tau PET, JPM outperformed linearregressionbased approach. Strong linear relationship was observed between CenTauRs values across brain regions.

Published
2024

2. Planet Hunters NGTS: New Planet Candidates from a Citizen Science Search of the Next Generation Transit Survey Public Data

Author

O'Brien, Sean M., Schwamb, Megan E., Gill, Samuel, Watson, Christopher A., Burleigh, Matthew R., Kendall, Alicia, Anderson, David R., Vines, José I., Jenkins, James S., Alves, Douglas R., Trouille, Laura, Ulmer-Moll, Solène, Bryant, Edward M., Apergis, Ioannis, Battley, Matthew P., Bayliss, Daniel, Eisner, Nora L., Gillen, Edward, Goad, Michael R., Günther, Maximilian N., Henderson, Beth A., Heo, Jeong-Eun, Jackson, David G., Lintott, Chris, McCormac, James, Moyano, Maximiliano, Nielsen, Louise D., Osborn, Ares, Saha, Suman, Sefako, Ramotholo R., Stephens, Andrew W., Tilbrook, Rosanna H., Udry, Stéphane, West, Richard G., Wheatley, Peter J., Zivave, Tafadzwa, Lim, See Min, and Sainio, Arttu

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We present the results from the first two years of the Planet Hunters NGTS citizen science project, which searches for transiting planet candidates in data from the Next Generation Transit Survey (NGTS) by enlisting the help of members of the general public. Over 8,000 registered volunteers reviewed 138,198 light curves from the NGTS Public Data Releases 1 and 2. We utilize a user weighting scheme to combine the classifications of multiple users to identify the most promising planet candidates not initially discovered by the NGTS team. We highlight the five most interesting planet candidates detected through this search, which are all candidate short-period giant planets. This includes the TIC-165227846 system that, if confirmed, would be the lowest-mass star to host a close-in giant planet. We assess the detection efficiency of the project by determining the number of confirmed planets from the NASA Exoplanet Archive and TESS Objects of Interest (TOIs) successfully recovered by this search and find that 74% of confirmed planets and 63% of TOIs detected by NGTS are recovered by the Planet Hunters NGTS project. The identification of new planet candidates shows that the citizen science approach can provide a complementary method to the detection of exoplanets with ground-based surveys such as NGTS., Comment: 42 pages, 20 figures, 17 tables. To be published in AJ

Published
2024
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5. CTCF is essential for proper mitotic spindle structure and anaphase segregation

Author

Chiu, Katherine, Berrada, Yasmin, Eskndir, Nebiyat, Song, Dasol, Fong, Claire, Naughton, Sarah, Chen, Tina, Moy, Savanna, Gyurmey, Sarah, James, Liam, Ezeiruaku, Chimere, Capistran, Caroline, Lowey, Daniel, Diwanji, Vedang, Peterson, Samantha, Parakh, Harshini, Burgess, Ayanna R., Probert, Cassandra, Zhu, Annie, Anderson, Bryn, Levi, Nehora, Gerlitz, Gabi, Packard, Mary C., Dorfman, Katherine A., Bahiru, Michael Seifu, and Stephens, Andrew D.

Published
2024
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6. Symmetry Enforced Fermi Surface Degeneracies Observed in Time-Reversal Symmetry-Breaking Superconductor LaNiGa$_2$

Author

Staab, Matthew, Prater, Robert, Sreedhar, Sudheer, Byland, Journey, Mann, Eliana, Zackaria, Davis, Shi, Yunshu, Bowman, Henry J., Stephens, Andrew L., Jung, Myung-Chul, Botana, Antia S., Pickett, Warren E., Taufour, Valentin, and Vishik, Inna

Subjects
Condensed Matter - Superconductivity
Abstract

LaNiGa$_2$ is superconductor that breaks time-reversal symmetry in the superconducting state without any known nearby magnetism. Recently, single crystals of LaNiGa$_2$ have been synthesized, revealing a nonsymmorphic Cmcm space group. Here, we report measurements of the electronic structure of LaNiGa$_2$ throughout the three-dimensional Brillouin zone (BZ) using angle-resolved photoemission spectroscopy (ARPES). Our findings show broad consistency with density functional theory (DFT) calculations and provide evidence for degeneracies in the electronic structure that are predicted from the space group. The calculations also predict four Fermi surfaces which cross the purported nodal plane and should therefore form two degenerate pairs. We report evidence for those predicted symmetry enforced degeneracies as well as accidental near degeneracies throughout the BZ. These degeneracies and near-degeneracies may play a role in the pairing mechanism of LaNiGa$_2$. Our results provide insight into the interplay between structure, Fermiology, and superconductivity in unconventional superconductors with nonsymmorphic space group., Comment: Main: 8 pages, 6 figures. SI: 6 pages, 8 figures

Published
2023

7. Qualitative and quantitative analysis of 18F-GP1 positron emission tomography in thrombotic cardiovascular disease

Author

Whittington, Beth, Tzolos, Evangelos, Joshi, Shruti, Bing, Rong, Andrews, Jack, Loganath, Krithika, Craig, Neil, Balmforth, Craig, Clark, Laura, Lucatelli, Christophe, MacAskill, Mark G, Tavares, Adriana A. S., Clark, Tim, Mills, Nicholas L., Nash, Jennifer, Dey, Damini, Slomka, Piotr J., Koglin, Norman, Stephens, Andrew W., Dweck, Marc R., Williams, Michelle C., Whiteley, William, van Beek, Edwin J. R., Wardlaw, Joanna M., and Newby, David E.

Published
2024
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8. Amyloid-PET imaging predicts functional decline in clinically normal individuals

Author

Quenon, Lisa, Collij, Lyduine E., Garcia, David Vállez, Lopes Alves, Isadora, Gérard, Thomas, Malotaux, Vincent, Huyghe, Lara, Gispert, Juan Domingo, Jessen, Frank, Visser, Pieter Jelle, den Braber, Anouk, Ritchie, Craig W., Boada, Mercè, Marquié, Marta, Vandenberghe, Rik, Luckett, Emma S., Schöll, Michael, Frisoni, Giovanni B., Buckley, Christopher, Stephens, Andrew, Altomare, Daniele, Ford, Lisa, Birck, Cindy, Mett, Anja, Gismondi, Rossella, Wolz, Robin, Grootoonk, Sylke, Manber, Richard, Shekari, Mahnaz, Lhommel, Renaud, Dricot, Laurence, Ivanoiu, Adrian, Farrar, Gill, Barkhof, Frederik, and Hanseeuw, Bernard J.

Published
2024
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10. The SN 2023ixf Progenitor in M101: II. Properties

Author

Van Dyk, Schuyler D., Srinivasan, Sundar, Andrews, Jennifer E., Soraisam, Monika, Szalai, Tamas, Howell, Steve B., Isaacson, Howard, Matheson, Thomas, Petigura, Erik, Scicluna, Peter, Stephens, Andrew W., Van Zandt, Judah, Zheng, WeiKang, Chun, Sang-Hyun, and Filippenko, Alexei V.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena
Abstract

We follow our first paper with an analysis of the ensemble of the extensive pre-explosion ground- and space-based infrared observations of the red supergiant (RSG) progenitor candidate for the nearby core-collapse supernova SN 2023ixf in Messier 101, together with optical data prior to explosion obtained with the Hubble Space Telescope (HST). We have confirmed the association of the progenitor candidate with the SN, as well as constrained the metallicity at the SN site, based on SN observations with instruments at Gemini-North. The internal host extinction to the SN has also been confirmed from a high-resolution Keck spectrum. We fit the observed spectral energy distribution (SED) for the star, accounting for its intrinsic variability, with dust radiative-transfer modeling, which assume a silicate-rich dust shell ahead of the underlying stellar photosphere. The star is heavily dust-obscured, likely the dustiest progenitor candidate yet encountered. We found median estimates of the star's effective temperature and luminosity of 2770 K and 9.0e4 L_Sun, with 68% credible intervals of 2340--3150 K and (7.5--10.9)e4 L_sun. The candidate may have a Galactic RSG analog, IRC -10414, with a strikingly similar SED and luminosity. Via comparison with single-star evolutionary models we have constrained the initial mass of the progenitor candidate from 12 M_sun to as high as 14 M_sun. We have had available to us an extraordinary view of the SN 2023ixf progenitor candidate, which should be further followed up in future years with HST and the James Webb Space Telescope., Comment: 40 pages, substantive modifications relative to the previous, although the overall conclusions remain the same; to appear in AAS Journals

Published
2023

11. Tau accumulation is associated with dopamine deficiency in vivo in four-repeat tauopathies

Author

Ferschmann, Christian, Messerschmidt, Konstantin, Gnörich, Johannes, Barthel, Henryk, Marek, Ken, Palleis, Carla, Katzdobler, Sabrina, Stockbauer, Anna, Fietzek, Urban, Finze, Anika, Biechele, Gloria, Rumpf, Jost-Julian, Saur, Dorothee, Schroeter, Matthias L., Rullmann, Michael, Beyer, Leonie, Eckenweber, Florian, Wall, Stephan, Schildan, Andreas, Patt, Marianne, Stephens, Andrew, Classen, Joseph, Bartenstein, Peter, Seibyl, John, Franzmeier, Nicolai, Levin, Johannes, Höglinger, Günter U., Sabri, Osama, Brendel, Matthias, and Scheifele, Maximilian

Published
2024
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14. End-to-end science operations in the era of extremely large telescopes

Author

Hainaut, Olivier R., Lemoine-Busserolle, Marie, Dumas, Christophe, Goodrich, Robert W., Miller, Bryan W., Sterzik, Michael F., Bierwirth, Thomas, Wolff, Sidney, Stephens, Andrew W., Trancho, Gelys, Skidmore, Warren, and Gillies, Kim

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Observatory end-to-end science operations is the overall process starting with a scientific question, represented by a proposal requesting observing time, and ending with the analysis of observation data addressing that question, and including all the intermediate steps needed to plan, schedule, obtain, and process these observations. Increasingly complex observing facilities demand a highly efficient science operations approach and at the same time be user friendly to the astronomical user community and enable the highest possible scientific return. Therefore, this process is supported by a collection of tools. In this paper, we describe the overall end-to-end process and its implementation for the three upcoming extremely large telescopes (ELTs), ESO's ELT, the Thirty Meter Telescope (TMT), and the Giant Magellan Telescope (GMT)., Comment: 38 pages, 20 figures. Revised submission to the SPIE Journal of Astronomical Telescopes, Instruments, and Systems

Published
2022

15. Gemini/GMOS Transmission Spectroscopy of the Grazing Planet Candidate WD 1856+534 b

Author

Xu, Siyi, Diamond-Lowe, Hannah, MacDonald, Ryan J., Vanderburg, Andrew, Blouin, Simon, Dufour, P., Gao, Peter, Kreidberg, Laura, Leggett, S. K., Mann, Andrew W., Morley, Caroline V., Stephens, Andrew W., O'Connor, Christopher E., Thao, Pa Chia, and Lewis, Nikole K.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

WD 1856+534 b is a Jupiter-sized, cool giant planet candidate transiting the white dwarf WD 1856+534. Here, we report an optical transmission spectrum of WD 1856+534 b obtained from ten transits using the Gemini Multi-Object Spectrograph. This system is challenging to observe due to the faintness of the host star and the short transit duration. Nevertheless, our phase-folded white light curve reached a precision of 0.12 %. WD 1856+534 b provides a unique transit configuration compared to other known exoplanets: the planet is $8\times$ larger than its star and occults over half of the stellar disc during mid-transit. Consequently, many standard modeling assumptions do not hold. We introduce the concept of a `limb darkening corrected, time-averaged transmission spectrum' and propose that this is more suitable than $(R_{\mathrm{p}, \lambda} / R_{\mathrm{s}})^2$ for comparisons to atmospheric models for planets with grazing transits. We also present a modified radiative transfer prescription. Though the transmission spectrum shows no prominent absorption features, it is sufficiently precise to constrain the mass of WD 1856+534 b to be > 0.84 M$_\mathrm{J}$ (to $2 \, \sigma$ confidence), assuming a clear atmosphere and a Jovian composition. High-altitude cloud decks can allow lower masses. WD 1856+534 b could have formed either as a result of common envelope evolution or migration under the Kozai-Lidov mechanism. Further studies of WD 1856+534 b, alongside new dedicated searches for substellar objects around white dwarfs, will shed further light on the mysteries of post-main sequence planetary systems., Comment: 21 pages, 10 figures, accepted for publication in AJ

Published
2021
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17. 18F-FSPG PET/CT Imaging of System xC- Transporter Activity in Patients with Primary and Metastatic Brain Tumors.

Author

Wardak, Mirwais, Sonni, Ida, Fan, Audrey P, Minamimoto, Ryogo, Jamali, Mehran, Hatami, Negin, Zaharchuk, Greg, Fischbein, Nancy, Nagpal, Seema, Li, Gordon, Koglin, Norman, Berndt, Mathias, Bullich, Santiago, Stephens, Andrew W, Dinkelborg, Ludger M, Abel, Ty, Manning, H Charles, Rosenberg, Jarrett, Chin, Frederick T, Gambhir, Sanjiv Sam, and Mittra, Erik S

Subjects
Biomedical and Clinical Sciences, Clinical Sciences, Oncology and Carcinogenesis, Rare Diseases, Clinical Trials and Supportive Activities, Biomedical Imaging, Cancer, Brain Cancer, Neurosciences, Clinical Research, Brain Disorders, 4.2 Evaluation of markers and technologies, Detection, screening and diagnosis, Brain Neoplasms, Fluorodeoxyglucose F18, Glutamic Acid, Humans, Male, Middle Aged, Positron Emission Tomography Computed Tomography, Positron-Emission Tomography, Prospective Studies, Radiopharmaceuticals, Medical and Health Sciences, Nuclear Medicine & Medical Imaging, Clinical sciences
Abstract

Background The PET tracer (4S)-4-(3-[18F]fluoropropyl)-l-glutamate (18F-FSPG) targets the system xC- cotransporter, which is overexpressed in various tumors. Purpose To assess the role of 18F-FSPG PET/CT in intracranial malignancies. Materials and Methods Twenty-six patients (mean age, 54 years ± 12; 17 men; 48 total lesions) with primary brain tumors (n = 17) or brain metastases (n = 9) were enrolled in this prospective, single-center study (ClinicalTrials.gov identifier: NCT02370563) between November 2014 and March 2016. A 30-minute dynamic brain 18F-FSPG PET/CT scan and a static whole-body (WB) 18F-FSPG PET/CT scan at 60-75 minutes were acquired. Moreover, all participants underwent MRI, and four participants underwent fluorine 18 (18F) fluorodeoxyglucose (FDG) PET imaging. PET parameters and their relative changes were obtained for all lesions. Kinetic modeling was used to estimate the 18F-FSPG tumor rate constants using the dynamic and dynamic plus WB PET data. Imaging parameters were correlated to lesion outcomes, as determined with follow-up MRI and/or pathologic examination. The Mann-Whitney U test or Student t test was used for group mean comparisons. Receiver operating characteristic curve analysis was used for performance comparison of different decision measures. Results 18F-FSPG PET/CT helped identify all 48 brain lesions. The mean tumor-to-background ratio (TBR) on the whole-brain PET images at the WB time point was 26.6 ± 24.9 (range: 2.6-150.3). When 18F-FDG PET was performed, 18F-FSPG permitted visualization of non-18F-FDG-avid lesions or allowed better lesion differentiation from surrounding tissues. In participants with primary brain tumors, the predictive accuracy of the relative changes in influx rate constant Ki and maximum standardized uptake value to discriminate between poor and good lesion outcomes were 89% and 81%, respectively. There were significant differences in the 18F-FSPG uptake curves of lesions with good versus poor outcomes in the primary brain tumor group (P < .05) but not in the brain metastases group. Conclusion PET/CT imaging with (4S)-4-(3-[18F]fluoropropyl)-l-glutamate (18F-FSPG) helped detect primary brain tumors and brain metastases with a high tumor-to-background ratio. Relative changes in 18F-FSPG uptake with multi-time-point PET appear to be helpful in predicting lesion outcomes. Clinical trial registration no. NCT02370563 © RSNA, 2022 Online supplemental material is available for this article.

Published
2022

18. ECMO PAL: using deep neural networks for survival prediction in venoarterial extracorporeal membrane oxygenation

Author

Stephens, Andrew F., Seman, Michael, Diehl, Arne, Pilcher, David, Barbaro, Ryan P., Brodie, Daniel, and Pellegrino, Vincent

Subjects
Artificial intelligence, Mortality -- Australia, Neural networks, Algorithms, Neural network, Algorithm, Artificial intelligence, Health care industry
Abstract

Purpose Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a complex and high-risk life support modality used in severe cardiorespiratory failure. ECMO survival scores are used clinically for patient prognostication and outcomes risk adjustment. This study aims to create the first artificial intelligence (AI)-driven ECMO survival score to predict in-hospital mortality based on a large international patient cohort. Methods A deep neural network, ECMO Predictive Algorithm (ECMO PAL) was trained on a retrospective cohort of 18,167 patients from the international Extracorporeal Life Support Organisation (ELSO) registry (2017-2020), and performance was measured using fivefold cross-validation. External validation was performed on all adult registry patients from 2021 (N = 5015) and compared against existing prognostication scores: SAVE, Modified SAVE, and ECMO ACCEPTS for predicting in-hospital mortality. Results Mean age was 56.8 ± 15.1 years, with 66.7% of patients being male and 50.2% having a pre-ECMO cardiac arrest. Cross-validation demonstrated an inhospital mortality sensitivity and precision of 82.1 ± 0.2% and 77.6 ± 0.2%, respectively. Validation accuracy was only 2.8% lower than training accuracy, reducing from 75.5% to 72.7% [99% confidence interval (CI) 71.1-74.3%]. ECMO PAL accuracy outperformed the ECMO ACCEPTS (54.7%), SAVE (61.1%), and Modified SAVE (62%) scores. Conclusions ECMO PAL is the first AI-powered ECMO survival score trained and validated on large international patient cohorts. ECMO PAL demonstrated high generalisability across ECMO regions and outperformed existing, widely used scores. Beyond ECMO, this study highlights how large international registry data can be leveraged for AI prognostication for complex critical care therapies., Author(s): Andrew F. Stephens [sup.1] [sup.9], Michael Seman [sup.1] [sup.2] [sup.3], Arne Diehl [sup.2] [sup.4], David Pilcher [sup.2] [sup.4], Ryan P. Barbaro [sup.5], Daniel Brodie [sup.6], Vincent Pellegrino [sup.4], David [...]

Published
2023
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21. Interferon-ε is a tumour suppressor and restricts ovarian cancer

Author

Marks, Zoe R. C., Campbell, Nicole K., Mangan, Niamh E., Vandenberg, Cassandra J., Gearing, Linden J., Matthews, Antony Y., Gould, Jodee A., Tate, Michelle D., Wray-McCann, Georgie, Ying, Le, Rosli, Sarah, Brockwell, Natasha, Parker, Belinda S., Lim, San S., Bilandzic, Maree, Christie, Elizabeth L., Stephens, Andrew N., de Geus, Eveline, Wakefield, Matthew J., Ho, Gwo-Yaw, McNally, Orla, McNeish, Iain A., Bowtell, David D. L., de Weerd, Nicole A., Scott, Clare L., Bourke, Nollaig M., and Hertzog, Paul J.

Published
2023
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22. Tau deposition patterns are associated with functional connectivity in primary tauopathies

Author

Franzmeier, Nicolai, Brendel, Matthias, Beyer, Leonie, Slemann, Luna, Kovacs, Gabor G, Arzberger, Thomas, Kurz, Carolin, Respondek, Gesine, Lukic, Milica J, Biel, Davina, Rubinski, Anna, Frontzkowski, Lukas, Hummel, Selina, Müller, Andre, Finze, Anika, Palleis, Carla, Joseph, Emanuel, Weidinger, Endy, Katzdobler, Sabrina, Song, Mengmeng, Biechele, Gloria, Kern, Maike, Scheifele, Maximilian, Rauchmann, Boris-Stephan, Perneczky, Robert, Rullman, Michael, Patt, Marianne, Schildan, Andreas, Barthel, Henryk, Sabri, Osama, Rumpf, Jost J, Schroeter, Matthias L, Classen, Joseph, Villemagne, Victor, Seibyl, John, Stephens, Andrew W, Lee, Edward B, Coughlin, David G, Giese, Armin, Grossman, Murray, McMillan, Corey T, Gelpi, Ellen, Molina-Porcel, Laura, Compta, Yaroslau, van Swieten, John C, Laat, Laura Donker, Troakes, Claire, Al-Sarraj, Safa, Robinson, John L, Xie, Sharon X, Irwin, David J, Roeber, Sigrun, Herms, Jochen, Simons, Mikael, Bartenstein, Peter, Lee, Virginia M, Trojanowski, John Q, Levin, Johannes, Höglinger, Günter, and Ewers, Michael

Subjects
Biochemistry and Cell Biology, Biological Sciences, Acquired Cognitive Impairment, Rare Diseases, Brain Disorders, Pick's Disease, Alzheimer's Disease, Dementia, Frontotemporal Dementia (FTD), Neurosciences, Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD), Neurodegenerative, Aging, Alzheimer's Disease Related Dementias (ADRD), Biomedical Imaging, Aetiology, 2.1 Biological and endogenous factors, Neurological, Brain, Humans, Magnetic Resonance Imaging, Supranuclear Palsy, Progressive, Tauopathies, tau Proteins
Abstract

Tau pathology is the main driver of neuronal dysfunction in 4-repeat tauopathies, including cortico-basal degeneration and progressive supranuclear palsy. Tau is assumed to spread prion-like across connected neurons, but the mechanisms of tau propagation are largely elusive in 4-repeat tauopathies, characterized not only by neuronal but also by astroglial and oligodendroglial tau accumulation. Here, we assess whether connectivity is associated with 4R-tau deposition patterns by combining resting-state fMRI connectomics with both 2nd generation 18F-PI-2620 tau-PET in 46 patients with clinically diagnosed 4-repeat tauopathies and post-mortem cell-type-specific regional tau assessments from two independent progressive supranuclear palsy patient samples (n = 97 and n = 96). We find that inter-regional connectivity is associated with higher inter-regional correlation of both tau-PET and post-mortem tau levels in 4-repeat tauopathies. In regional cell-type specific post-mortem tau assessments, this association is stronger for neuronal than for astroglial or oligodendroglial tau, suggesting that connectivity is primarily associated with neuronal tau accumulation. Using tau-PET we find further that patient-level tau patterns are associated with the connectivity of subcortical tau epicenters. Together, the current study provides combined in vivo tau-PET and histopathological evidence that brain connectivity is associated with tau deposition patterns in 4-repeat tauopathies.

Published
2022

23. A local baseline of the black hole mass scaling relations for active galaxies. IV. Correlations between $M_{\rm BH}$ and host galaxy $\sigma$, stellar mass, and luminosity

Author

Bennert, Vardha N., Treu, Tommaso, Ding, Xuheng, Stomberg, Isak, Birrer, Simon, Snyder, Tomas, Malkan, Matthew A., Stephens, Andrew W., and Auger, Matthew W.

Subjects
Astrophysics - Astrophysics of Galaxies, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The tight correlations between the mass of supermassive black holes ($M_{\rm BH}$) and their host-galaxy properties have been of great interest to the astrophysical community, but a clear understanding of their origin and fundamental drivers still eludes us. The local relations for active galaxies are interesting in their own right and form the foundation for any evolutionary study over cosmic time. We present Hubble Space Telescope optical imaging of a sample of 66 local active galactic nuclei (AGNs); for 14 objects, we also obtained Gemini near-infrared images. We use state of the art methods to perform surface photometry of the AGN host galaxies, decomposing them in spheroid, disk and bar (when present) and inferring the luminosity and stellar mass of the components. We combine this information with spatially-resolved kinematics obtained at the Keck Telescopes to study the correlations between $M_{\rm BH}$ (determined from single-epoch virial estimators) and host galaxy properties. The correlations are uniformly tight for our AGN sample, with intrinsic scatter 0.2-0.4 dex, smaller than or equal to that of quiescent galaxies. We find no difference between pseudo and classical bulges or barred and non-barred galaxies. We show that all the tight correlations can be simultaneously satisfied by AGN hosts in the 10$^7$-10$^9$ $M_{\odot}$ regime, with data of sufficient quality. The MBH-$\sigma$ relation is also in agreement with that of AGNs with $M_{\rm BH}$ obtained from reverberation mapping, providing an indirect validation of single-epoch virial estimators of $M_{\rm BH}$., Comment: 29 pages, 7 figures, 5 tables, accepted by ApJ

Published
2021
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26. Recruitment of pre-dementia participants: main enrollment barriers in a longitudinal amyloid-PET study

Author

Bader, Ilse, Bader, Ilona, Lopes Alves, Isadora, Vállez García, David, Vellas, Bruno, Dubois, Bruno, Boada, Mercè, Marquié, Marta, Altomare, Daniele, Scheltens, Philip, Vandenberghe, Rik, Hanseeuw, Bernard, Schöll, Michael, Frisoni, Giovanni B., Jessen, Frank, Nordberg, Agneta, Kivipelto, Miia, Ritchie, Craig W., Grau-Rivera, Oriol, Molinuevo, José Luis, Ford, Lisa, Stephens, Andrew, Gismondi, Rossella, Gispert, Juan Domingo, Farrar, Gill, Barkhof, Frederik, Visser, Pieter Jelle, and Collij, Lyduine E.

Published
2023
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27. [18F]F-DED PET imaging of reactive astrogliosis in neurodegenerative diseases: preclinical proof of concept and first-in-human data

Author

Ballweg, Anna, Klaus, Carolin, Vogler, Letizia, Katzdobler, Sabrina, Wind, Karin, Zatcepin, Artem, Ziegler, Sibylle I., Secgin, Birkan, Eckenweber, Florian, Bohr, Bernd, Bernhardt, Alexander, Fietzek, Urban, Rauchmann, Boris-Stephan, Stoecklein, Sophia, Quach, Stefanie, Beyer, Leonie, Scheifele, Maximilian, Simmet, Marcel, Joseph, Emanuel, Lindner, Simon, Berg, Isabella, Koglin, Norman, Mueller, Andre, Stephens, Andrew W., Bartenstein, Peter, Tonn, Joerg C., Albert, Nathalie L., Kümpfel, Tania, Kerschensteiner, Martin, Perneczky, Robert, Levin, Johannes, Paeger, Lars, Herms, Jochen, and Brendel, Matthias

Published
2023
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29. A local baseline of the black hole mass scaling relations for active galaxies. IV. Correlations between $M_{\rm BH}$ and host galaxy $σ$, stellar mass, and luminosity

Author

Bennert, Vardha N, Treu, Tommaso, Ding, Xuheng, Stomberg, Isak, Birrer, Simon, Snyder, Tomas, Malkan, Matthew A, Stephens, Andrew W, and Auger, Matthew W

Subjects
astro-ph.GA, astro-ph.CO
Abstract

The tight correlations between the mass of supermassive black holes ($M_{\rmBH}$) and their host-galaxy properties have been of great interest to theastrophysical community, but a clear understanding of their origin andfundamental drivers still eludes us. The local relations for active galaxiesare interesting in their own right and form the foundation for any evolutionarystudy over cosmic time. We present Hubble Space Telescope optical imaging of asample of 66 local active galactic nuclei (AGNs); for 14 objects, we alsoobtained Gemini near-infrared images. We use state of the art methods toperform surface photometry of the AGN host galaxies, decomposing them inspheroid, disk and bar (when present) and inferring the luminosity and stellarmass of the components. We combine this information with spatially-resolvedkinematics obtained at the Keck Telescopes to study the correlations between$M_{\rm BH}$ (determined from single-epoch virial estimators) and host galaxyproperties. The correlations are uniformly tight for our AGN sample, withintrinsic scatter 0.2-0.4 dex, smaller than or equal to that of quiescentgalaxies. We find no difference between pseudo and classical bulges or barredand non-barred galaxies. We show that all the tight correlations can besimultaneously satisfied by AGN hosts in the 10$^7$-10$^9$ $M_{\odot}$ regime,with data of sufficient quality. The MBH-$\sigma$ relation is also in agreementwith that of AGNs with $M_{\rm BH}$ obtained from reverberation mapping,providing an indirect validation of single-epoch virial estimators of $M_{\rmBH}$.

Published
2021

31. Additive value of [18F]PI-2620 perfusion imaging in progressive supranuclear palsy and corticobasal syndrome

Author

Katzdobler, Sabrina, Nitschmann, Alexander, Barthel, Henryk, Bischof, Gerard, Beyer, Leonie, Marek, Ken, Song, Mengmeng, Wagemann, Olivia, Palleis, Carla, Weidinger, Endy, Nack, Anne, Fietzek, Urban, Kurz, Carolin, Häckert, Jan, Stapf, Theresa, Ferschmann, Christian, Scheifele, Maximilian, Eckenweber, Florian, Biechele, Gloria, Franzmeier, Nicolai, Dewenter, Anna, Schönecker, Sonja, Saur, Dorothee, Schroeter, Matthias L., Rumpf, Jost-Julian, Rullmann, Michael, Schildan, Andreas, Patt, Marianne, Stephens, Andrew W., van Eimeren, Thilo, Neumaier, Bernd, Drzezga, Alexander, Danek, Adrian, Classen, Joseph, Bürger, Katharina, Janowitz, Daniel, Rauchmann, Boris-Stephan, Stöcklein, Sophia, Perneczky, Robert, Schöberl, Florian, Zwergal, Andreas, Höglinger, Günter U., Bartenstein, Peter, Villemagne, Victor, Seibyl, John, Sabri, Osama, Levin, Johannes, and Brendel, Matthias

Published
2023
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34. Size and Shape Constraints of (486958) Arrokoth from Stellar Occultations

Author

Buie, Marc W., Porter, Simon B., Tamblyn, Peter, Terrell, Dirk, Parker, Alex Harrison, Baratoux, David, Kaire, Maram, Leiva, Rodrigo, Verbiscer, Anne J., Zangari, Amanda M., Colas, François, Diop, Baïdy Demba, Samaniego, Joseph I., Wasserman, Lawrence H., Benecchi, Susan D., Caspi, Amir, Gwyn, Stephen, Kavelaars, J. J., Uría, Adriana C. Ocampo, Rabassa, Jorge, Skrutskie, M. F., Soto, Alejandro, Tanga, Paolo, Young, Eliot F., Stern, S. Alan, Andersen, Bridget C., Pérez, Mauricio E. Arango, Arredondo, Anicia, Artola, Rodolfo Alfredo, Bâ, Abdoulaye, Ballet, Romuald, Blank, Ted, Bop, Cheikh Tidiane, Bosh, Amanda S., López, Matías Aarón Camino, Carter, Christian M., Castro-Chacón, J. H., Desprez, Alfonso Caycedo, Guerra, Nicolás Caycedo, Conard, Steven J., Dauvergne, Jean-Luc, Dean, Bryan, Dean, Michelle, Desmars, Josselin, Dieng, Abdou Lahat, Dieng, Mame Diarra Bousso, Diouf, Omar, Dorego, Gualbert Séraphin, Dunham, David W., Dunham, Joan, Luca, Hugo A. Durantini, Edwards, Patrick, Erasmus, Nicolas, Faye, Gayane, Faye, Mactar, Ferrario, Lucas Ezequiel, Ferrell, Chelsea L., Finley, Tiffany J., Fraser, Wesley C., Friedli, Alison J., Serna, Julián Galvez, Garcia-Migani, Esteban A., Genade, Anja, Getrost, Kai, Gil-Hutton, Ricardo A., Gimeno, German N., Golub, Eli Joseph, Murillo, Giovanni Francisco González, Grusin, Michael D., Gurovich, Sebastian, Hanna, William H., Henn, Santiago M., Hinton, P. C., Hughes, Paul J., Josephs Jr, John David, Joya, Raul, Kammer, Joshua A., Keeney, Brian A., Keller, John M., Kramer, Emily A., Levine, Stephen E., Lisse, Carey M., Lovell, Amy J., Mackie, Jason A., Makarchuk, Stanislav, Manzano, Luis E., Mbaye, Salma Sylla, Mbaye, Modou, Melia, Raul Roberto, Moreno, Freddy, Moss, Sean K., Ndaiye, Diene, Ndiaye, Mapathe, Nelson, Matthew J., Olkin, Catherine B., Olsen, Aart M., Moreno, Victor Jonathan Ospina, Pasachoff, Jay M., Pereyra, Mariana Belen, Person, Michael J., Pinzón, Giovanni, Pulver, Eduardo Alejandro, Quintero, Edwin A., Regester, Jeffrey R., Resnick, Aaron Caleb, Reyes-Ruiz, Mauricio, Rolfsmeier, Alex D., Ruhland, Trina R., Salmon, Julien, Santos-Sanz, Pablo, Santucho, Marcos Ariel, Niño, Diana Karina Sepúlveda, Sickafoose, Amanda A., Silva, José S., Singer, Kelsi N., Skipper, Joy N., Slivan, Stephen M., Smith, Rose J. C., Spagnotto, Julio C., Stephens, Andrew W., Strabala, Samuel D., Tamayo, Francisco J., Throop, Henry B., Cañas, Andrés David Torres, Toure, Labaly, Traore, Alassane, Tsang, Constantine C. C., Turner, Jake D., Vanegas, Santiago, Venable, Roger, Wilson, John C., Zuluaga, Carlos A., and Zuluaga, Jorge I.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

We present the results from four stellar occultations by (486958) Arrokoth, the flyby target of the New Horizons extended mission. Three of the four efforts led to positive detections of the body, and all constrained the presence of rings and other debris, finding none. Twenty-five mobile stations were deployed for 2017 June 3 and augmented by fixed telescopes. There were no positive detections from this effort. The event on 2017 July 10 was observed by SOFIA with one very short chord. Twenty-four deployed stations on 2017 July 17 resulted in five chords that clearly showed a complicated shape consistent with a contact binary with rough dimensions of 20 by 30 km for the overall outline. A visible albedo of 10% was derived from these data. Twenty-two systems were deployed for the fourth event on 2018 Aug 4 and resulted in two chords. The combination of the occultation data and the flyby results provides a significant refinement of the rotation period, now estimated to be 15.9380 $\pm$ 0.0005 hours. The occultation data also provided high-precision astrometric constraints on the position of the object that were crucial for supporting the navigation for the New Horizons flyby. This work demonstrates an effective method for obtaining detailed size and shape information and probing for rings and dust on distant Kuiper Belt objects as well as being an important source of positional data that can aid in spacecraft navigation that is particularly useful for small and distant bodies., Comment: Submitted to Astronomical Journal (revised); 40 pages, 13 figures, 9 tables

Published
2019
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35. Noninvasive In Vivo Coronary Artery Thrombus Imaging

Author

Tzolos, Evangelos, Bing, Rong, Andrews, Jack, MacAskill, Mark G., Tavares, Adriana A.S., Macnaught, Gillian, Clark, Tim, Mills, Nicholas L., Fujisawa, Takeshi, Nash, Jennifer, Dey, Damini, Slomka, Piotr J., Koglin, Norman, Stephens, Andrew W., Deutsch, Marcus-Andre, van Beek, Edwin J.R., Williams, Michelle C., Hermann, Sven, Hugenberg, Verena, Dweck, Marc R., and Newby, David E.

Published
2023
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46. Noninvasive In Vivo Thrombus Imaging in Patients With Ischemic Stroke or Transient Ischemic Attack—Brief Report

Author

Whittington, Beth, Tzolos, Evangelos, Bing, Rong, Andrews, Jack, Lucatelli, Christophe, MacAskill, Mark G., Tavares, Adriana A.S., Clark, Tim, Mills, Nicholas L., Nash, Jennifer, Dey, Damini, Slomka, Piotr J., Koglin, Norman, Stephens, Andrew W., van Beek, Edwin J.R., Smith, Colin, Dweck, Marc R., Williams, Michelle C., Whiteley, William, Wardlaw, Joanna M., and Newby, David E.

Published
2023
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48. 18F-GP1 Positron Emission Tomography and Bioprosthetic Aortic Valve Thrombus

Author

Bing, Rong, Deutsch, Marcus-André, Sellers, Stephanie L., Corral, Carlos Alcaide, Andrews, Jack P.M., van Beek, Edwin J.R., Bleiziffer, Sabine, Burchert, Wolfgang, Clark, Tim, Dey, Damini, Friedrichs, Kai, Gummert, Jan F., Koglin, Norman, Leipsic, Jonathon A., Lindner, Oliver, MacAskill, Mark G., Milting, Hendrik, Pessotto, Renzo, Preuss, Rainer, Raftis, Jennifer B., Rudolph, Tanja K., Rudolph, Volker, Slomka, Piotr, Stephens, Andrew W., Tavares, Adriana, Tzolos, Evangelos, Weir, Nick, White, Audrey C., Williams, Michelle C., Zabel, Reinhard, Dweck, Marc R., Hugenberg, Verena, and Newby, David E.

Published
2022
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