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5,808 results on '"Weiss, J. A."'

1. A tale of $Z$+jet: SMEFT effects and the Lam-Tung relation

Author

Gauld, R., Haisch, U., and Weiss, J.

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

We derive constraints on dimension-six light-quark dipole operators within the Standard Model (SM) effective field theory, based on measurements of $Z$ production at SLC and LEP, as well as $Z$+jet production at the LHC. Our new constraints exclude the parameter space that could potentially explain the observed discrepancy between theoretical predictions and experimental data for the Lam-Tung relation. With these updated limits, we model-independently determine the maximum possible influence that beyond-SM contributions could have on the angular coefficients $A_0$ and $A_2$, which enter the Lam-Tung relation., Comment: 22 pages, 5 figures

Published
2024

3. Aftershocks as a time independant phenomenon

Author

Mathey, A., Crassous, J., Marsan, D., Weiss, J., and Amon, A.

Subjects
Physics - Geophysics, Condensed Matter - Soft Condensed Matter
Abstract

Sequences of aftershocks following Omori's empirical law are observed after most major earthquakes, as well as in laboratory-scale fault-mimicking experiments. Nevertheless, the origin of this memory effect is still unclear. In this letter, we present an analytical framework for treating labquake and earthquake catalogs on an equal footing. Using this analysis method, we show that when memory is considered to be in deformation and not in time, all data collapse onto a single master curve, showing that the timescale is entirely fixed by the inverse of the strain rate.

Published
2024

4. On the Low-Frequency Dynamics of Turbulent Separation Bubbles

Author

Cura, C., Hanifi, A., Cavalieri, A. V. G., and Weiss, J.

Subjects
Physics - Fluid Dynamics
Abstract

The low-frequency modal and non-modal stability characteristics of an incompressible, pressure-gradient-induced turbulent separation bubble (TSB) are investigated with the objective of studying the mechanism responsible for the low-frequency contraction and expansion (breathing) commonly observed in experimental studies. The configuration of interest is a TSB generated on a flat test surface by a succession of adverse and favourable pressure gradients. The base flow selected for the analysis is the average TSB from the direct numerical simulation of Coleman et al. (J. Fluid Mech., vol. 847, 2018). Global linear stability analysis reveals that the flow is globally stable for wavenumbers. The mode closest to the stability threshold appears to occur at zero frequency and low, non-zero spanwise wavenumber. Resolvent analysis is then employed to examine the forced dynamics of the flow. At low frequency, a region of low, non-zero spanwise wavenumber is also discernible, where the receptivity appears to be driven by the identified weakly damped global mode. The results from resolvent analysis are compared to the unsteady experimental database of Le Floc'h et al. (J. Fluid Mech., vol. 902, 2020) in a similar TSB flow. The alignment between the optimal response and the first spectral proper orthogonal decomposition mode computed from the experiments is shown to exceed 95 %, while the spanwise wavenumber of the optimal response is consistent with that of the low-frequency breathing motion captured experimentally. This indicates that the fluctuations observed experimentally at low frequency closely match the response computed from resolvent analysis. Based on these results, we propose that the forced dynamics of the flow, driven by the weakly damped global mode, serve as a plausible mechanism for the origin of the low-frequency breathing motion commonly observed in experimental studies of TSBs.

Published
2023
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6. Design and characteristics of the prophylactic intra-operative ventricular arrhythmia ablation in high-risk LVAD candidates (PIVATAL) trial.

Author

Huang, David, Gosev, Igor, Wood, Katherine, Vidula, Hima, Stevenson, William, Marchlinski, Frank, Supple, Gregory, Zalawadiya, Sandip, Weiss, J, Tung, Roderick, Tzou, Wendy, Moss, Joshua, Kancharla, Krishna, Chaudhry, Sunit-Preet, Patel, Parin, Khan, Arfaat, Schuger, Claudio, Rozen, Guy, Kiernan, Michael, Couper, Gregory, Leacche, Marzia, Molina, Ezequiel, Shah, Anand, Lloyd, Michael, Sroubek, Jakub, Soltesz, Edward, Shivkumar, Kalyanam, White, Casey, Tankut, Sinan, Johnson, Brent, McNitt, Scott, Kutyifa, Valentina, Zareba, Wojciech, and Goldenberg, Ilan

Subjects
ablation, left ventricular assist device, ventricular tachycardia, Humans, Heart-Assist Devices, Prospective Studies, Quality of Life, Risk Factors, Electrocardiography, Arrhythmias, Cardiac, Tachycardia, Ventricular, Heart Failure, Defibrillators, Implantable, Treatment Outcome
Abstract

BACKGROUND: The use of a Left Ventricular Assist Device (LVAD) in patients with advanced heart failure refractory to optimal medical management has progressed steadily over the past two decades. Data have demonstrated reduced LVAD efficacy, worse clinical outcome, and higher mortality for patients who experience significant ventricular tachyarrhythmia (VTA). We hypothesize that a novel prophylactic intra-operative VTA ablation protocol at the time of LVAD implantation may reduce the recurrent VTA and adverse events postimplant. METHODS: We designed a prospective, multicenter, open-label, randomized-controlled clinical trial enrolling 100 patients who are LVAD candidates with a history of VTA in the previous 5 years. Enrolled patients will be randomized in a 1:1 fashion to intra-operative VTA ablation (n = 50) versus conventional medical management (n = 50) with LVAD implant. Arrhythmia outcomes data will be captured by an implantable cardioverter defibrillator (ICD) to monitor VTA events, with a uniform ICD programming protocol. Patients will be followed prospectively over a mean of 18 months (with a minimum of 9 months) after LVAD implantation to evaluate recurrent VTA, adverse events, and procedural outcomes. Secondary endpoints include right heart function/hemodynamics, healthcare utilization, and quality of life. CONCLUSION: The primary aim of this first-ever randomized trial is to assess the efficacy of intra-operative ablation during LVAD surgery in reducing VTA recurrence and improving clinical outcomes for patients with a history of VTA.

Published
2023

7. Critical Current Measurement of REBCO Cables by Using a Superconducting Transformer

Author

Yu, H., Lu, J., Weiss, J. D., and van der Laan, D. C.

Subjects
Condensed Matter - Superconductivity
Abstract

Development of REBCO cables that carry high electrical current in high magnetic field is crucial for future large-scale magnet applications. This experimental work presents the critical current measurements of two different REBCO cables by a test facility at the National High Magnetic Field Laboratory (NHMFL). The simple-stacked cable is made by the NHMFL by stacking 21 REBCO tapes without soldering. The Conductor-on-Round-Core (CORC) cable provided by Advanced Conductor Technologies has 21 layers of REBCO tapes with 2 tapes/layer. The test facility consists of a 12 T split solenoid magnet with 15 cm bore providing transverse field to the samples, a superconducting transformer (SCT) as a current source providing up to 45 kA current. Special attentions were paid to fabrication of solder joints between REBCO cables and the SCT output. The voltage-current traces were measured as a function of magnetic field at 4.2 K, from which the critical currents are determined. The details of this measurement are discussed.

Published
2023
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10. HRS policy statement on catheter ablation of atrial fibrillation

Author

Liu, Christopher F., Berman, Adam E., Chung, Mina K., Dukes, Jonathan, Ellenbogen, Kenneth A., Greenberg, Scott J., Hadziabdulahovic, Sabina, Kanagasundram, Arvindh N., Larsen, Timothy R., Mainigi, Sumeet K., Sachdev, Molly, Schoenfeld, Mark H., Slotwiner, David J., Thosani, Amit, Weiss, J. Peter, Miller, Lisa, Smith, Anne Marie, and Shanker, Amit J.

Published
2025
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11. An Initial Look at the Magnetic Design of a 150 mm Aperture High-Temperature Superconducting Magnet With a Dipole Field of 8 to 10 T

Author

Wang, X, Arbelaez, D, Brouwer, L, Caspi, S, Ferracin, P, Fajardo, L Garcia, Gourlay, S, Higley, H, Juchno, M, Marchevsky, M, Pong, I, Prestemon, S, Fernandez, JL Rudeiros, Sabbi, G, Shen, T, Teyber, R, Vallone, G, van der Laan, D, and Weiss, J

Subjects
Nuclear and Plasma Physics, Physical Sciences, Arc magnet, muon collider, REBCO, high-temperature superconducting magnet, Condensed Matter Physics, Electrical and Electronic Engineering, Materials Engineering, General Physics, Electrical engineering, Condensed matter physics
Abstract

High-temperature superconducting REBa{2} Cu{3}O{7-x} (rebco) conductors have the potential to generate a high magnetic field over a broad temperature range. The corresponding accelerator magnet technology, still in its infancy, can be attractive for future energy-frontier particle colliders such as a multi-TeV muon collider. To help develop the technology, we explore the requirements and potential characteristics of a rebco magnet, operating at 4.2 or 20 K, with a dipole field of 8-10 T in a clear aperture of 150 mm. We use the canted \cos \theta magnet configuration to reduce the electromagnetic stresses on the conductors. We present the resulting dipole fields, field gradients for combined-function cases, conductor stresses, magnet dimensions and conductor lengths. We also discuss the conductor performance that is required to achieve the target dipole field at 4.2 and 20 K. The information can provide useful input to the development of rebco magnet and conductor technology for collider-ring magnets in a muon collider.

Published
2023

12. Interleukin (IL)-1/IL-6-Inhibitor–Associated Drug Reaction With Eosinophilia and Systemic Symptoms (DReSS) in Systemic Inflammatory Illnesses

Author

Aamir, R., Abulaban, K., Adams, A., Lapsia, C. Aguiar, Akinsete, A., Akoghlanian, S., Al Manaa, M., AlBijadi, A., Allenspach, E., Almutairi, A., Alperin, R., Amarilyo, G., Ambler, W., Amoruso, M., Angeles-Han, S., Ardoin, S., Armendariz, S., Asfaw, L., Aviran Dagan, N., Bacha, C., Balboni, I., Balevic, S., Ballinger, S., Baluta, S., Barillas-Arias, L., Basiaga, M., Baszis, K., Baxter, S., Becker, M., Begezda, A., Behrens, E., Beil, E., Benseler, S., Bermudez-Santiago, L., Bernal, W., Bigley, T., Bingham, C., Binstadt, B., Black, C., Blackmon, B., Blakley, M., Bohnsack, J., Boneparth, A., Bradfield, H., Bridges, J., Brooks, E., Brothers, M., Brunner, H., Buckley, L., Buckley, M., Bukulmez, H., Bullock, D., Canna, S., Cannon, L., Canny, S., Cartwright, V., Cassidy, E., Castro, D., Chalom, E., Chang, J., Chang, M., Chang-Hoftman, A., Chen, A., Chiraseveenuprapund, P., Ciaglia, K., Co, D., Cohen, E., Collinge, J., Conlon, H., Connor, R., Cook, K., Cooper, A., Cooper, J., Corbin, K., Correll, C., Cron, R., Curry, M., Dalrymple, A., Datyner, E., Davis, T., De Ranieri, D., Dean, J., DeCoste, C., Dedeoglu, F., DeGuzman, M., Delnay, N., DeSantis, E., Devine, R., Dhalla, M., Dhanrajani, A., Dissanayake, D., Dizon, B., Drapeau, N., Drew, J., Driest, K., Du, Q., Duncan, E., Dunnock, K., Durkee, D., Dvergsten, J., Eberhard, A., Ede, K., Edelheit, B., Edens, C., El Tal, T., Elder, M., Elzaki, Y., Fadrhonc, S., Failing, C., Fair, D., Favier, L., Feldman, B., Fennell, J., Ferguson, P., Ferguson, I., Figueroa, C., Flanagan, E., Fogel, L., Fox, E., Fox, M., Franklin, L., Fuhlbrigge, R., Fuller, J., Furey, M., Futch-West, T., Gagne, S., Gennaro, V., Gerstbacher, D., Gilbert, M., Gironella, A., Glaser, D., Goh, I., Goldsmith, D., Gorry, S., Goswami, N., Gottlieb, B., Graham, T., Grevich, S., Griffin, T., Grim, A., Grom, A., Guevara, M., Hahn, T., Halyabar, O., Hamda Natur, M., Hammelev, E., Hammond, T., Harel, L., Harris, J., Harry, O., Hausmann, J., Hay, A., Hays, K., Hayward, K., Henderson, L., Henrickson, M., Hersh, A., Hickey, K., Hiraki, L., Hiskey, M., Hobday, P., Hoffart, C., Holland, M., Hollander, M., Hong, S., Horton, D., Horwitz, M., Hsu, J., Huber, A., Huberts, A., Huggins, J., Huie, L., Hui-Yuen, J., Ibarra, M., Imlay, A., Imundo, L., Inman, C., Jackson, A., James, K., Janow, G., Jared, S., Jiang, Y., Johnson, L., Johnson, N., Jones, J., Kafisheh, D., Kahn, P., Kaidar, K., Kasinathan, S., Kaur, R., Kessler, E., Kienzle, B., Kim, S., Kimura, Y., Kingsbury, D., Kitcharoensakkul, M., Klausmeier, T., Klein, K., Klein-Gitelman, M., Knight, A., Kovalick, L., Kramer, S., Kremer, C., Kudas, O., LaFlam, T., Lang, B., Lapidus, S., Lapin, B., Lasky, A., Lawler, C., Lawson, E., Laxer, R., Lee, P., Lee, T., Lee, A., Leisinger, E., Lentini, L., Lerman, M., Levinsky, Y., Levy, D., Li, S., Lieberman, S., Lim, L., Limenis, E., Lin, C., Ling, N., Lionetti, G., Livny, R., Lloyd, M., Lo, M., Long, A., Lopez-Peña, M., Lovell, D., Luca, N., Lvovich, S., Lytch, A., Ma, M., Machado, A., MacMahon, J., Madison, J., Mannion, M., Manos, C., Mansfield, L., Marston, B., Mason, T., Matchett, D., McAllister, L., McBrearty, K., McColl, J., McCurdy, D., McDaniels, K., McDonald, J., Meidan, E., Mellins, E., Mian, Z., Miettunen, P., Miller, M., Milojevic, D., Mitacek, R., Modica, R., Mohan, S., Moore, T., Moore, K., Moorthy, L., Moreno, J., Morgan, E., Moyer, A., Murante, B., Murphy, A., Muscal, E., Mwizerwa, O., Najafi, A., Nanda, K., Nasah, N., Nassi, L., Nativ, S., Natter, M., Nearanz, K., Neely, J., Newhall, L., Nguyen, A., Nigrovic, P., Nocton, J., Nolan, B., Nowicki, K., Oakes, R., Oberle, E., Ogbonnaya-Whittesley, S., Ogbu, E., Oliver, M., Olveda, R., Onel, K., Orandi, A., Padam, J., Paller, A., Pan, N., Pandya, J., Panupattanapong, S., Toledano, A. Pappo, Parsons, A., Patel, J., Patel, P., Patrick, A., Patrizi, S., Paul, S., Perfetto, J., Perron, M., Peskin, M., Ponder, L., Pooni, R., Prahalad, S., Puplava, B., Quinlan-Waters, M., Rabinovich, C., Rafko, J., Rahimi, H., Rampone, K., Ramsey, S., Randell, R., Ray, L., Reed, A., Reid, H., Reiff, D., Richins, S., Riebschleger, M., Rife, E., Riordan, M., Riskalla, M., Robinson, A., Robinson, L., Rodgers, L., Rodriquez, M., Rogers, D., Ronis, T., Rosado, A., Rosenkranz, M., Rosenwasser, N., Rothermel, H., Rothman, D., Rothschild, E., Roth-Wojcicki, E., Rouster-Stevens, K., Rubinstein, T., Rupp, J., Ruth, N., Sabbagh, S., Sadun, R., Santiago, L., Saper, V., Sarkissian, A., Scalzi, L., Schahn, J., Schikler, K., Schlefman, A., Schmeling, H., Schmitt, E., Schneider, R., Schulert, G., Schultz, K., Schutt, C., Seper, C., Sheets, R., Shehab, A., Shenoi, S., Sherman, M., Shirley, J., Shishov, M., Siegel, D., Singer, N., Sivaraman, V., Sloan, E., Smith, C., Smith, J., Smitherman, E., Soep, J., Son, Mary B., Sosna, D., Spencer, C., Spiegel, L., Spitznagle, J., Srinivasalu, H., Stapp, H., Steigerwald, K., Stephens, A., Sterba Rakovchik, Y., Stern, S., Stevens, B., Stevenson, R., Stewart, K., Stewart, W., Stingl, C., Stoll, M., Stringer, E., Sule, S., Sullivan, J., Sundel, R., Sutter, M., Swaffar, C., Swayne, N., Syed, R., Symington, T., Syverson, G., Szymanski, A., Taber, S., Tal, R., Tambralli, A., Taneja, A., Tanner, T., Tarvin, S., Tate, L., Taxter, A., Taylor, J., Tesher, M., Thakurdeen, T., Theisen, A., Thomas, B., Thomas, L., Thomas, N., Ting, T., Todd, C., Toib, D., Torok, K., Tory, H., Toth, M., Tse, S., Tsin, C., Twachtman-Bassett, J., Twilt, M., Valcarcel, T., Valdovinos, R., Vallee, A., Van Mater, H., Vandenbergen, S., Vannoy, L., Varghese, C., Vasquez, N., Vega-Fernandez, P., Velez, J., Verbsky, J., Verstegen, R., von Scheven, E., Vora, S., Wagner-Weiner, L., Wahezi, D., Waite, H., Walker, B., Walters, H., Waterfield, M., Waters, A., Weiser, P., Weiss, P., Weiss, J., Wershba, E., Westheuser, V., White, A., Widrick, K., Williams, C., Wong, S., Woolnough, L., Wright, T., Wu, E., Yalcindag, A., Yasin, S., Yeung, R., Yomogida, K., Zeft, A., Zhang, Y., Zhao, Y., Zhu, A., Saper, Vivian E., Tian, Lu, Verstegen, Ruud H.J., Conrad, Carol K., Cidon, Michal, Hopper, Rachel K., Kuo, Christin S., Osoegawa, Kazutoyo, Baszis, Kevin, Bingham, Catherine A., Ferguson, Ian, Hahn, Timothy, Horne, Annacarin, Isupova, Eugenia A., Jones, Jordan T., Kasapcopur, Özgür, Klein-Gitelman, Marisa S., Kostik, Mikhail M., Ozen, Seza, Phadke, Omkar, Prahalad, Sampath, Randell, Rachel L., Sener, Seher, Stingl, Cory, Abdul-Aziz, Rabheh, Akoghlanian, Shoghik, Al Julandani, Dalila, Alvarez, Marcela B., Bader-Meunier, Brigitte, Balay-Dustrude, Erin E., Balboni, Imelda, Baxter, Sarah K., Berard, Roberta A., Bhattad, Sagar, Bolaria, Roxana, Boneparth, Alexis, Cassidy, Elaine A., Co, Dominic O., Collins, Kathleen P., Dancey, Paul, Dickinson, Aileen M., Edelheit, Barbara S., Espada, Graciela, Flanagan, Elaine R., Imundo, Lisa F., Jindal, Ankur K., Kim, Hyoun-Ah, Klaus, Günter, Lake, Carol, Lapin, W. Blaine, Lawson, Erica F., Marmor, Itay, Mombourquette, Joy, Ogunjimi, Benson, Olveda, Rebecca, Ombrello, Michael J., Onel, Karen, Poholek, Catherine, Ramanan, Athimalaipet V., Ravelli, Angelo, Reinhardt, Adam, Robinson, Amanda D., Rouster-Stevens, Kelly, Saad, Nadine, Schneider, Rayfel, Selmanovic, Velma, Sefic Pasic, Irmina, Shenoi, Susan, Shilo, Natalie R., Soep, Jennifer B., Sura, Angeli, Taber, Sarah F., Tesher, Melissa, Tibaldi, Jessica, Torok, Kathryn S., Tsin, Cathy Mei, Vasquez-Canizares, Natalia, Villacis Nunez, Diana S., Way, Emily E., Whitehead, Benjamin, Zemel, Lawrence S., Sharma, Surbhi, Fernández-Viña, Marcelo A., and Mellins, Elizabeth D.

Published
2024
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16. Capturing the Range of Disease Involvement in Localized Scleroderma: The Localized Scleroderma Total Severity Scale

Author

Li, Suzanne C., Rabinovich, C. Egla, Becker, Mara L., Torok, Kathryn S., Ferguson, Polly J., Dedeoglu, Fatma, Hong, Sandy, Sivaraman, Vidya, Laxer, Ronald M., Stewart, Katie, Ibarra, Maria F., Mason, Thomas, II, Higgins, Gloria, Pope, Elena, Li, Xiaohu, Lozy, Tara, Fuhlbrigge, Robert C., Anderson, E., Benham, H., Feldman, B., Francis, K., Goh, I., Jaquith, J., SchollaertFitch, K., Smith, C., Weiss, J., and Wooton, J.

Published
2024
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17. Developing a Vacuum Pressure Impregnation Procedure for CORC Wires

Author

Stern, J, Swanson, J, Bogdanof, T, Krutulis, M, Weiss, J, van der Laan, D, Wang, X, and Chiesa, L

Subjects
Engineering, Synchrotrons and Accelerators, Physical Sciences, Affordable and Clean Energy, Wires, Degradation, Heating systems, Bending, Superconducting magnets, Curing, Aluminum, High energy physics, high temperature superconductors, nuclear fusion, rare earth barium copper oxide, vacuum pressure impregnation, Condensed Matter Physics, Electrical and Electronic Engineering, Materials Engineering, General Physics, Electrical engineering, Condensed matter physics
Abstract

Superconducting magnets designed for high energy physics and nuclear fusion require mechanical and electrical integrity to perform at high currents and magnetic fields. Vacuum Pressure Impregnation (VPI), a process of curing epoxy in and around the superconducting wires, is often used to support and consolidate a magnet. However, the heat and mechanical stresses associated with the process can degrade the wires, significantly lowering their critical current. This study explores different methods of potting and curing CORC wire with the aim of reducing wire performance degradation to less than 3% measured at 77 K, self-field. The wires were 2.9 mm in diameter consisting of a total of six REBCO tapes (three layers of two tapes). Two bending radii (20 mm and 50 mm) were tested to mimic the winding shape of a magnet. Mix 61 epoxy was used in preliminary tests for potting. For each test, two wires were used, and their critical currents were measured simultaneously in liquid nitrogen at 77 K - in their straight form, then bent, followed by the heat treatment used for Mix 61 but without epoxy and finishing with the full epoxy impregnation test. Later tests were performed using CTD-528 to explore a room temperature cure, limiting possibility of degradation from thermal expansion and prolonged exposure of the REBCO tapes to elevated temperature. Here we report the experimental results with multiple CORC wires and different curing schedules. The results obtained are the first steps toward identifying the VPI process with minimum degradation in critical current to be implemented in high-field magnets using CORC wires.

Published
2022

18. Variety of scaling behaviors in nanocrystalline plasticity

Author

Zhang, P., Salman, O. U., Weiss, J., and Truskinovsky, L.

Subjects
Condensed Matter - Soft Condensed Matter, Condensed Matter - Materials Science, Physics - Computational Physics
Abstract

We address the question of why larger, high symmetry crystals are mostly weak, ductile and statistically sub-critical, while smaller crystals with the same symmetry are strong, brittle and super-critical. We link it to another question of why intermittent elasto-plastic deformation of sub-micron crystals features highly unusual size sensitivity of scaling exponents. We use a minimal integer-valued automaton model of crystal plasticity to show that with growing variance of quenched disorder, which can serve in this case as a proxy for increasing size, sub-micron crystals undergo a crossover from spin-glass marginality to criticality characterizing the second order brittle-to-ductile (BD) transition. We argue that this crossover is behind the non-universality of scaling exponents observed in physical and numerical experiments. The non-universality emerges only if the quenched disorder is elastically incompatible and it disappears if the disorder is compatible.

Published
2020
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22. Effects of Aerobic Exercise Training on Daily Psychological Processes in Family Caregivers: Secondary Analyses of a Randomized Controlled Trial

Author

Caplin, A, Beauchamp, MR, Weiss, J, Schilf, S, Hives, B, DeLongis, A, Johansen, KL, Epel, ES, and Puterman, E

Subjects
Clinical and Health Psychology, Health Services and Systems, Health Sciences, Psychology, Clinical Research, Clinical Trials and Supportive Activities, Brain Disorders, Behavioral and Social Science, 6.6 Psychological and behavioural, Good Health and Well Being, Aerobic exercise, Affective states, Ecological momentary assessments, Perceived control, Randomized controlled trial, Rumination
Abstract

The aim of this study was to examine the effects of a 24-week aerobic exercise training program on daily psychological processes and occurrence of stressors in a group of previously physically underactive family caregivers of patients with dementia. As part of the Fitness, Aging, and STress (FAST) randomized controlled trial, 68 participants (F = 55; M = 13) were randomized to either a staff-supported, 24-week aerobic training (N = 34) program or waitlist control (N = 34) group. Approximately 2 weeks prior to randomization, ecological momentary assessments were completed 6 times per day for 7 days and again in the 24th week of the trial to assess exposure to levels of momentary positive affect, negative affect, rumination, control, and the occurrence of stressors throughout the day. These secondary analyses with data from 56 of the participants revealed that the intervention group showed a significantly larger increase in daily positive affect and perceptions of control compared to control participants over the course of the intervention. A treatment effect was also found for negative affect and rumination, whereby both decreased to a greater extent in the intervention group when compared with participants in the control condition. The 24-week aerobic training program had significant impacts on daily psychological processes in family caregivers, deepening our understanding of the robust effects of exercise on mental health.

Published
2021

23. Group Virtual Mindfulness-Based Intervention for Parents of Autistic Adolescents and Adults

Author

Lunsky, Y., Albaum, C., Baskin, A., Hastings, R. P., Hutton, S., Steel, L., Wang, W., and Weiss, J.

Abstract

Mindfulness-based approaches have been shown to be effective in improving the mental health of parents of youth and adults with autism and other developmental disabilities, but prior work suggests that geography and caregiving demands can make in-person attendance challenging. The purpose of this study was to evaluate the feasibility, acceptability and preliminary outcomes of a mindfulness-based group intervention delivered to parents virtually. It was feasible to deliver this manualized intervention. Twenty-one of 39 parents completed the intervention and completers reported high satisfaction ratings. Parents reported reduced levels of distress, maintained at 3-month follow-up, and increased mindfulness. Changes reported following intervention were similar to changes reported in a prior study of parents competing an in person mindfulness group.

Published
2021
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25. Health Equity Implications of Missing Data Among Youths With Childhood‐Onset Systemic Lupus Erythematosus: A Proof‐of‐Concept Study in the Childhood Arthritis and Rheumatology Research Alliance Registry

Author

Woo, Jennifer M. P., Simmonds, Faith, Dennos, Anne, Son, Mary Beth F., Lewandowski, Laura B., Rubinstein, Tamar B., Abel, N., Abulaban, K., Adams, A., Adams, M., Agbayani, R., Aiello, J., Akoghlanian, S., Alejandro, C., Allenspach, E., Alperin, R., Alpizar, M., Amarilyo, G., Ambler, W., Anderson, E., Ardoin, S., Armendariz, S., Baker, E., Balboni, I., Balevic, S., Ballenger, L., Ballinger, S., Balmuri, N., Barbar‐Smiley, F., Barillas‐Arias, L., Basiaga, M., Baszis, K., Becker, M., Bell‐Brunson, H., Beltz, E., Benham, H., Benseler, S., Bernal, W., Beukelman, T., Bigley, T., Binstadt, B., Black, C., Blakley, M., Bohnsack, J., Boland, J., Boneparth, A., Bowman, S., Bracaglia, C., Brooks, E., Brothers, M., Brown, A., Brunner, H., Buckley, M., Buckley, M., Bukulmez, H., Bullock, D., Cameron, B., Canna, S., Cannon, L., Carper, P., Cartwright, V., Cassidy, E., Cerracchio, L., Chalom, E., Chang, J., Chang‐Hoftman, A., Chauhan, V., Chira, P., Chinn, T., Chundru, K., Clairman, H., Co, D., Confair, A., Conlon, H., Connor, R., Cooper, A., Cooper, J., Cooper, S., Correll, C., Corvalan, R., Costanzo, D., Cron, R., Curiel‐Duran, L., Curington, T., Curry, M., Dalrymple, A., Davis, A., Davis, C., Davis, C., Davis, T., De Benedetti, F., De Ranieri, D., Dean, J., Dedeoglu, F., DeGuzman, M., Delnay, N., Dempsey, V., DeSantis, E., Dickson, T., Dingle, J., Donaldson, B., Dorsey, E., Dover, S., Dowling, J., Drew, J., Driest, K., Du, Q., Duarte, K., Durkee, D., Duverger, E., Dvergsten, J., Eberhard, A., Eckert, M., Ede, K., Edelheit, B., Edens, C., Edens, C., Edgerly, Y., Elder, M., Ervin, B., Fadrhonc, S., Failing, C., Fair, D., Falcon, M., Favier, L., Federici, S., Feldman, B., Fennell, J., Ferguson, I., Ferguson, P., Ferreira, B., Ferrucho, R., Fields, K., Finkel, T., Fitzgerald, M., Fleming, C., Flynn, O., Fogel, L., Fox, E., Fox, M., Franco, L., Freeman, M., Fritz, K., Froese, S., Fuhlbrigge, R., Fuller, J., George, N., Gerhold, K., Gerstbacher, D., Gilbert, M., Gillispie‐Taylor, M., Giverc, E., Godiwala, C., Goh, I., Goheer, H., Goldsmith, D., Gotschlich, E., Gotte, A., Gottlieb, B., Gracia, C., Graham, T., Grevich, S., Griffin, T., Griswold, J., Grom, A., Guevara, M., Guittar, P., Guzman, M., Hager, M., Hahn, T., Halyabar, O., Hammelev, E., Hance, M., Hanson, A., Harel, L., Haro, S., Harris, J., Harry, O., Hartigan, E., Hausmann, J., Hay, A., Hayward, K., Heiart, J., Hekl, K., Henderson, L., Henrickson, M., Hersh, A., Hickey, K., Hill, P., Hillyer, S., Hiraki, L., Hiskey, M., Hobday, P., Hoffart, C., Holland, M., Hollander, M., Hong, S., Horwitz, M., Hsu, J., Huber, A., Huggins, J., Hui‐Yuen, J., Hung, C., Huntington, J., Huttenlocher, A., Ibarra, M., Imundo, L., Inman, C., Insalaco, A., Jackson, A., Jackson, S., James, K., Janow, G., Jaquith, J., Jared, S., Johnson, N., Jones, J., Jones, J., Jones, J., Jones, K., Jones, S., Joshi, S., Jung, L., Justice, C., Justiniano, A., Karan, N., Kaufman, K., Kemp, A., Kessler, E., Khalsa, U., Kienzle, B., Kim, S., Kimura, Y., Kingsbury, D., Kitcharoensakkul, M., Klausmeier, T., Klein, K., Klein‐Gitelman, M., Kompelien, B., Kosikowski, A., Kovalick, L., Kracker, J., Kramer, S., Kremer, C., Lai, J., Lam, J., Lang, B., Lapidus, S., Lapin, B., Lasky, A., Latham, D., Lawson, E., Laxer, R., Lee, P., Lee, P., Lee, T., Lentini, L., Lerman, M., Levy, D., Li, S., Lieberman, S., Lim, L., Lin, C., Ling, N., Lingis, M., Lo, M., Lovell, D., Lowman, D., Luca, N., Lvovich, S., Madison, C., Madison, J., Manzoni, S. Magni, Malla, B., Maller, J., Malloy, M., Mannion, M., Manos, C., Marques, L., Martyniuk, A., Mason, T., Mathus, S., McAllister, L., McCarthy, K., McConnell, K., McCormick, E., McCurdy, D., Stokes, P. McCurdy, McGuire, S., McHale, I., McMonagle, A., McMullen‐Jackson, C., Meidan, E., Mellins, E., Mendoza, E., Mercado, R., Merritt, A., Michalowski, L., Miettunen, P., Miller, M., Milojevic, D., Mirizio, E., Misajon, E., Mitchell, M., Modica, R., Mohan, S., Moore, K., Moorthy, L., Morgan, S., Dewitt, E. Morgan, Moss, C., Moussa, T., Mruk, V., Murphy, A., Muscal, E., Nadler, R., Nahal, B., Nanda, K., Nasah, N., Nassi, L., Nativ, S., Natter, M., Neely, J., Nelson, B., Newhall, L., Ng, L., Nicholas, J., Nicolai, R., Nigrovic, P., Nocton, J., Nolan, B., Oberle, E., Obispo, B., OʼBrien, B., OʼBrien, T., Okeke, O., Oliver, M., Olson, J., OʼNeil, K., Onel, K., Orandi, A., Orlando, M., Osei‐Onomah, S., Oz, R., Pagano, E., Paller, A., Pan, N., Panupattanapong, S., Pardeo, M., Paredes, J., Parsons, A., Patel, J., Pentakota, K., Pepmueller, P., Pfeiffer, T., Phillippi, K., Phillippi, K., Marafon, D. Pires, Ponder, L., Pooni, R., Prahalad, S., Pratt, S., Protopapas, S., Puplava, B., Quach, J., Quinlan‐Waters, M., Rabinovich, C., Radhakrishna, S., Rafko, J., Raisian, J., Rakestraw, A., Ramirez, C., Ramsay, E., Ramsey, S., Randell, R., Reed, A., Reed, A., Reed, A., Reid, H., Remmel, K., Repp, A., Reyes, A., Richmond, A., Riebschleger, M., Ringold, S., Riordan, M., Riskalla, M., Ritter, M., Rivas‐Chacon, R., Robinson, A., Rodela, E., Rodriquez, M., Rojas, K., Ronis, T., Rosenkranz, M., Rosolowski, B., Rothermel, H., Rothman, D., Roth‐Wojcicki, E., Rouster‐Stevens, K., Rubinstein, T., Ruth, N., Saad, N., Sabbagh, S., Sacco, E., Sadun, R., Sandborg, C., Sanni, A., Santiago, L., Sarkissian, A., Savani, S., Scalzi, L., Schanberg, L., Scharnhorst, S., Schikler, K., Schlefman, A., Schmeling, H., Schmidt, K., Schmitt, E., Schneider, R., Schollaert‐Fitch, K., Schulert, G., Seay, T., Seper, C., Shalen, J., Sheets, R., Shelly, A., Shenoi, S., Shergill, K., Shirley, J., Shishov, M., Shivers, C., Silverman, E., Singer, N., Sivaraman, V., Sletten, J., Smith, A., Smith, C., Smith, J., Smith, J., Smitherman, E., Soep, J., Son, M., Spence, S., Spiegel, L., Spitznagle, J., Sran, R., Srinivasalu, H., Stapp, H., Steigerwald, K., Rakovchik, Y. Sterba, Stern, S., Stevens, A., Stevens, B., Stevenson, R., Stewart, K., Stingl, C., Stokes, J., Stoll, M., Stringer, E., Sule, S., Sumner, J., Sundel, R., Sutter, M., Syed, R., Syverson, G., Szymanski, A., Taber, S., Tal, R., Tambralli, A., Taneja, A., Tanner, T., Tapani, S., Tarshish, G., Tarvin, S., Tate, L., Taxter, A., Taylor, J., Terry, M., Tesher, M., Thatayatikom, A., Thomas, B., Tiffany, K., Ting, T., Tipp, A., Toib, D., Torok, K., Toruner, C., Tory, H., Toth, M., Tse, S., Tubwell, V., Twilt, M., Uriguen, S., Valcarcel, T., Van Mater, H., Vannoy, L., Varghese, C., Vasquez, N., Vazzana, K., Vehe, R., Veiga, K., Velez, J., Verbsky, J., Vilar, G., Volpe, N., von Scheven, E., Vora, S., Wagner, J., Wagner‐Weiner, L., Wahezi, D., Waite, H., Walker, J., Walters, H., Muskardin, T. Wampler, Waqar, L., Waterfield, M., Watson, M., Watts, A., Weiser, P., Weiss, J., Weiss, P., Wershba, E., White, A., Williams, C., Wise, A., Woo, J., Woolnough, L., Wright, T., Wu, E., Yalcindag, A., Yee, M., Yen, E., Yeung, R., Yomogida, K., Yu, Q., Zapata, R., Zartoshti, A., Zeft, A., Zeft, R., Zhang, Y., Zhao, Y., Zhu, A., and Zic, C.

Published
2023
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26. Durvalumab with or without tremelimumab versus the EXTREME regimen as first-line treatment for recurrent or metastatic squamous cell carcinoma of the head and neck: KESTREL, a randomized, open-label, phase III study

Author

Psyrri, A., Fayette, J., Harrington, K., Gillison, M., Ahn, M.-J., Takahashi, S., Weiss, J., Machiels, J.-P., Baxi, S., Vasilyev, A., Karpenko, A., Dvorkin, M., Hsieh, C.-Y., Thungappa, S.C., Segura, P.P., Vynnychenko, I., Haddad, R., Kasper, S., Mauz, P.-S., Baker, V., He, P., Evans, B., Wildsmith, S., Olsson, R.F., Yovine, A., Kurland, J.F., Morsli, N., and Seiwert, T.Y.

Published
2023
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28. Experimental 3D Coherent Diffractive Imaging from photon-sparse random projections

Author

Giewekemeyer, K., Aquila, A., Loh, N. D., Chushkin, Y., Shanks, K. S., Weiss, J., Tate, M. W., Philipp, H. T., Stern, S., Vagovic, P., Mehrjoo, M., Teo, C., Barthelmess, M., Zontone, F., Chang, C., Tiberio, R. C., Sakdinawat, A., Williams, G. J., Gruner, S. M., and Mancuso, A. P.

Subjects
Physics - Applied Physics, Physics - Data Analysis, Statistics and Probability, Physics - Instrumentation and Detectors, Physics - Optics
Abstract

The routine atomic-resolution structure determination of single particles is expected to have profound implications for probing the structure-function relationship in systems ranging from energy materials to biological molecules. Extremely-bright, ultrashort-pulse X-ray sources---X-ray Free Electron Lasers (XFELs)---provide X-rays that can be used to probe ensembles of nearly identical nano-scale particles. When combined with coherent diffractive imaging, these objects can be imaged; however, as the resolution of the images approaches the atomic scale, the measured data are increasingly difficult to obtain and, during an X-ray pulse, the number of photons incident on the two-dimensional detector is much smaller than the number of pixels. This latter concern, the signal "sparsity," materially impedes the application of the method. We demonstrate an experimental analog using a synchrotron X-ray source that yields signal levels comparable to those expected from single biomolecules illuminated by focused XFEL pulses. The analog experiment provides an invaluable cross-check on the fidelity of the reconstructed data that is not available during XFEL experiments. We establish---using this experimental data---that a sparsity of order $1.3\times10^{-3}$ photons per pixel per frame can be overcome, lending vital insight to the solution of the atomic-resolution XFEL single particle imaging problem by experimentally demonstrating 3D coherent diffractive imaging from photon-sparse random projections., Comment: 17 pages, 12 figures

Published
2018

31. Childhood‐Onset Lupus Nephritis in the Childhood Arthritis and Rheumatology Research Alliance Registry: Short‐Term Kidney Status and Variation in Care

Author

Smitherman, Emily A., Chahine, Rouba A., Beukelman, Timothy, Lewandowski, Laura B., Rahman, A. K. M. Fazlur, Wenderfer, Scott E., Curtis, Jeffrey R., Hersh, Aimee O., Abel, N., Abulaban, K., Adams, A., Adams, M., Agbayani, R., Aiello, J., Akoghlanian, S., Alejandro, C., Allenspach, E., Alperin, R., Alpizar, M., Amarilyo, G., Ambler, W., Anderson, E., Ardoin, S., Armendariz, S., Baker, E., Balboni, I., Balevic, S., Ballenger, L., Ballinger, S., Balmuri, N., Barbar‐Smiley, F., Barillas‐Arias, L., Basiaga, M., Baszis, K., Becker, M., Bell‐Brunson, H., Beltz, E., Benham, H., Benseler, S., Bernal, W., Beukelman, T., Bigley, T., Binstadt, B., Black, C., Blakley, M., Bohnsack, J., Boland, J., Boneparth, A., Bowman, S., Bracaglia, C., Brooks, E., Brothers, M., Brown, A., Brunner, H., Buckley, M., Buckley, M., Bukulmez, H., Bullock, D., Cameron, B., Canna, S., Cannon, L., Carper, P., Cartwright, V., Cassidy, E., Cerracchio, L., Chalom, E., Chang, J., Chang‐Hoftman, A., Chauhan, V., Chira, P., Chinn, T., Chundru, K., Clairman, H., Co, D., Confair, A., Conlon, H., Connor, R., Cooper, A., Cooper, J., Cooper, S., Correll, C., Corvalan, R., Costanzo, D., Cron, R., Curiel‐Duran, L., Curington, T., Curry, M., Dalrymple, A., Davis, A., Davis, C., Davis, C., Davis, T., De Benedetti, F., De Ranieri, D., Dean, J., Dedeoglu, F., DeGuzman, M., Delnay, N., Dempsey, V., DeSantis, E., Dickson, T., Dingle, J., Donaldson, B., Dorsey, E., Dover, S., Dowling, J., Drew, J., Driest, K., Du, Q., Duarte, K., Durkee, D., Duverger, E., Dvergsten, J., Eberhard, A., Eckert, M., Ede, K., Edelheit, B., Edens, C., Edens, C., Edgerly, Y., Elder, M., Ervin, B., Fadrhonc, S., Failing, C., Fair, D., Falcon, M., Favier, L., Federici, S., Feldman, B., Fennell, J., Ferguson, I., Ferguson, P., Ferreira, B., Ferrucho, R., Fields, K., Finkel, T., Fitzgerald, M., Fleming, C., Flynn, O., Fogel, L., Fox, E., Fox, M., Franco, L., Freeman, M., Fritz, K., Froese, S., Fuhlbrigge, R., Fuller, J., George, N., Gerhold, K., Gerstbacher, D., Gilbert, M., Gillispie‐Taylor, M., Giverc, E., Godiwala, C., Goh, I., Goheer, H., Goldsmith, D., Gotschlich, E., Gotte, A., Gottlieb, B., Gracia, C., Graham, T., Grevich, S., Griffin, T., Griswold, J., Grom, A., Guevara, M., Guittar, P., Guzman, M., Hager, M., Hahn, T., Halyabar, O., Hammelev, E., Hance, M., Hanson, A., Harel, L., Haro, S., Harris, J., Harry, O., Hartigan, E., Hausmann, J., Hay, A., Hayward, K., Heiart, J., Hekl, K., Henderson, L., Henrickson, M., Hersh, A., Hickey, K., Hill, P., Hillyer, S., Hiraki, L., Hiskey, M., Hobday, P., Hoffart, C., Holland, M., Hollander, M., Hong, S., Horwitz, M., Hsu, J., Huber, A., Huggins, J., Hui‐Yuen, J., Hung, C., Huntington, J., Huttenlocher, A., Ibarra, M., Imundo, L., Inman, C., Insalaco, A., Jackson, A., Jackson, S., James, K., Janow, G., Jaquith, J., Jared, S., Johnson, N., Jones, J., Jones, J., Jones, J., Jones, K., Jones, S., Joshi, S., Jung, L., Justice, C., Justiniano, A., Karan, N., Kaufman, K., Kemp, A., Kessler, E., Khalsa, U., Kienzle, B., Kim, S., Kimura, Y., Kingsbury, D., Kitcharoensakkul, M., Klausmeier, T., Klein, K., Klein‐Gitelman, M., Kompelien, B., Kosikowski, A., Kovalick, L., Kracker, J., Kramer, S., Kremer, C., Lai, J., Lam, J., Lang, B., Lapidus, S., Lapin, B., Lasky, A., Latham, D., Lawson, E., Laxer, R., Lee, P., Lee, P., Lee, T., Lentini, L., Lerman, M., Levy, D., Li, S., Lieberman, S., Lim, L., Lin, C., Ling, N., Lingis, M., Lo, M., Lovell, D., Lowman, D., Luca, N., Lvovich, S., Madison, C., Madison, J., Manzoni, S. Magni, Malla, B., Maller, J., Malloy, M., Mannion, M., Manos, C., Marques, L., Martyniuk, A., Mason, T., Mathus, S., McAllister, L., McCarthy, K., McConnell, K., McCormick, E., McCurdy, D., Stokes, P. McCurdy, McGuire, S., McHale, I., McMonagle, A., McMullen‐Jackson, C., Meidan, E., Mellins, E., Mendoza, E., Mercado, R., Merritt, A., Michalowski, L., Miettunen, P., Miller, M., Milojevic, D., Mirizio, E., Misajon, E., Mitchell, M., Modica, R., Mohan, S., Moore, K., Moorthy, L., Morgan, S., Dewitt, E. Morgan, Moss, C., Moussa, T., Mruk, V., Murphy, A., Muscal, E., Nadler, R., Nahal, B., Nanda, K., Nasah, N., Nassi, L., Nativ, S., Natter, M., Neely, J., Nelson, B., Newhall, L., Ng, L., Nicholas, J., Nicolai, R., Nigrovic, P., Nocton, J., Nolan, B., Oberle, E., Obispo, B., OʼBrien, B., OʼBrien, T., Okeke, O., Oliver, M., Olson, J., OʼNeil, K., Onel, K., Orandi, A., Orlando, M., Osei‐Onomah, S., Oz, R., Pagano, E., Paller, A., Pan, N., Panupattanapong, S., Pardeo, M., Paredes, J., Parsons, A., Patel, J., Pentakota, K., Pepmueller, P., Pfeiffer, T., Phillippi, K., Marafon, D. Pires, Phillippi, K., Ponder, L., Pooni, R., Prahalad, S., Pratt, S., Protopapas, S., Puplava, B., Quach, J., Quinlan‐Waters, M., Rabinovich, C., Radhakrishna, S., Rafko, J., Raisian, J., Rakestraw, A., Ramirez, C., Ramsay, E., Ramsey, S., Randell, R., Reed, A., Reed, A., Reed, A., Reid, H., Remmel, K., Repp, A., Reyes, A., Richmond, A., Riebschleger, M., Ringold, S., Riordan, M., Riskalla, M., Ritter, M., Rivas‐Chacon, R., Robinson, A., Rodela, E., Rodriquez, M., Rojas, K., Ronis, T., Rosenkranz, M., Rosolowski, B., Rothermel, H., Rothman, D., Roth‐Wojcicki, E., Rouster – Stevens, K., Rubinstein, T., Ruth, N., Saad, N., Sabbagh, S., Sacco, E., Sadun, R., Sandborg, C., Sanni, A., Santiago, L., Sarkissian, A., Savani, S., Scalzi, L., Schanberg, L., Scharnhorst, S., Schikler, K., Schlefman, A., Schmeling, H., Schmidt, K., Schmitt, E., Schneider, R., Schollaert‐Fitch, K., Schulert, G., Seay, T., Seper, C., Shalen, J., Sheets, R., Shelly, A., Shenoi, S., Shergill, K., Shirley, J., Shishov, M., Shivers, C., Silverman, E., Singer, N., Sivaraman, V., Sletten, J., Smith, A., Smith, C., Smith, J., Smith, J., Smitherman, E., Soep, J., Son, M., Spence, S., Spiegel, L., Spitznagle, J., Sran, R., Srinivasalu, H., Stapp, H., Steigerwald, K., Rakovchik, Y. Sterba, Stern, S., Stevens, A., Stevens, B., Stevenson, R., Stewart, K., Stingl, C., Stokes, J., Stoll, M., Stringer, E., Sule, S., Sumner, J., Sundel, R., Sutter, M., Syed, R., Syverson, G., Szymanski, A., Taber, S., Tal, R., Tambralli, A., Taneja, A., Tanner, T., Tapani, S., Tarshish, G., Tarvin, S., Tate, L., Taxter, A., Taylor, J., Terry, M., Tesher, M., Thatayatikom, A., Thomas, B., Tiffany, K., Ting, T., Tipp, A., Toib, D., Torok, K., Toruner, C., Tory, H., Toth, M., Tse, S., Tubwell, V., Twilt, M., Uriguen, S., Valcarcel, T., Van Mater, H., Vannoy, L., Varghese, C., Vasquez, N., Vazzana, K., Vehe, R., Veiga, K., Velez, J., Verbsky, J., Vilar, G., Volpe, N., von Scheven, E., Vora, S., Wagner, J., Wagner‐Weiner, L., Wahezi, D., Waite, H., Walker, J., Walters, H., Muskardin, T. Wampler, Waqar, L., Waterfield, M., Watson, M., Watts, A., Weiser, P., Weiss, J., Weiss, P., Wershba, E., White, A., Williams, C., Wise, A., Woo, J., Woolnough, L., Wright, T., Wu, E., Yalcindag, A., Yee, M., Yen, E., Yeung, R., Yomogida, K., Yu, Q., Zapata, R., Zartoshti, A., Zeft, A., Zeft, R., Zhang, Y., Zhao, Y., Zhu, A., and Zic, C.

Published
2023
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32. Predictive Score for Identifying Survival and Recurrence Risk Profiles in Patients Undergoing Ventricular Tachycardia Ablation

Author

Vergara, Pasquale, Tzou, Wendy S, Tung, Roderick, Brombin, Chiara, Nonis, Alessandro, Vaseghi, Marmar, Frankel, David S, Di Biase, Luigi, Tedrow, Usha, Mathuria, Nilesh, Nakahara, Shiro, Tholakanahalli, Venkat, Bunch, T Jared, Weiss, J Peter, Dickfeld, Timm, Lakireddy, Dhanunjaya, Burkhardt, J David, Santangeli, Pasquale, Callans, David, Natale, Andrea, Marchlinski, Francis, Stevenson, William G, Shivkumar, Kalyanam, Sauer, William H, and Della Bella, Paolo

Subjects
Biomedical and Clinical Sciences, Clinical Sciences, Clinical Research, Heart Disease, Cardiovascular, Good Health and Well Being, Age Factors, Aged, Aged, 80 and over, Catheter Ablation, Cohort Studies, Databases, Factual, Decision Trees, Electrocardiography, Follow-Up Studies, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Predictive Value of Tests, ROC Curve, Recurrence, Retrospective Studies, Risk Assessment, Severity of Illness Index, Sex Factors, Stroke Volume, Survival Analysis, Tachycardia, Ventricular, Time Factors, Treatment Outcome, cardiomyopathies, catheter ablation, mortality, risk assessment, ventricular tachycardia, Cardiorespiratory Medicine and Haematology, Medical Physiology, Cardiovascular System & Hematology, Cardiovascular medicine and haematology, Clinical sciences, Medical physiology
Abstract

BackgroundSeveral distinct risk factors for arrhythmia recurrence and mortality following ventricular tachycardia (VT) ablation have been described. The effect of concurrent risk factors has not been assessed so far; thus, it is not yet possible to estimate these risks for a patient with several comorbidities. The aim of the study was to identify specific risk groups for mortality and VT recurrence using the Survival Tree (ST) analysis method.MethodsIn 1251 patients 16 demographic, clinical and procedure-related variables were evaluated as potential prognostic factors using ST analysis using a recursive partitioning algorithm that searches for relationships among variables. Survival time and time to VT recurrence in groups derived from ST analysis were compared by a log-rank test. A random forest analysis was then run to extract a variable importance index and internally validate the ST models.ResultsLeft ventricular ejection fraction, implantable cardioverter defibrillator/cardiac resynchronization device, previous ablation were, in hierarchical order, identified by ST analysis as best predictors of VT recurrence, while left ventricular ejection fraction, previous ablation, Electrical storm were identified as best predictors of mortality. Three groups with significantly different survival rates were identified. Among the high-risk group, 65.0% patients were survived and 52.1% patients were free from VT recurrence; within the medium- and low-risk groups, 84.0% and 97.2% patients survived, 72.4% and 88.4% were free from VT recurrence, respectively.ConclusionsOur study is the first to derive and validate a decisional model that provides estimates of VT recurrence and mortality with an effective classification tree. Preprocedure risk stratification could help optimize periprocedural and postprocedural care.

Published
2018

33. Outcomes of Catheter Ablation of Ventricular Tachycardia Based on Etiology in Nonischemic Heart Disease: An International Ventricular Tachycardia Ablation Center Collaborative Study.

Author

Vaseghi, Marmar, Hu, Tiffany Y, Tung, Roderick, Vergara, Pasquale, Frankel, David S, Di Biase, Luigi, Tedrow, Usha B, Gornbein, Jeffrey A, Yu, Ricky, Mathuria, Nilesh, Nakahara, Shiro, Tzou, Wendy S, Sauer, William H, Burkhardt, J David, Tholakanahalli, Venkatakrishna N, Dickfeld, Timm-Michael, Weiss, J Peter, Bunch, T Jared, Reddy, Madhu, Callans, David J, Lakkireddy, Dhanunjaya R, Natale, Andrea, Marchlinski, Francis E, Stevenson, William G, Della Bella, Paolo, and Shivkumar, Kalyanam

Subjects
Humans, Tachycardia, Ventricular, Cardiomyopathies, Catheter Ablation, Treatment Outcome, Retrospective Studies, Adult, Aged, Middle Aged, Female, Male, ablation, arrhythmogenic right ventricular cardiomyopathy, myocarditis, nonischemic, sarcoidosis, valvular, ventricular tachycardia, Rare Diseases, Autoimmune Disease, Cardiovascular, Heart Disease, Clinical Research, Cardiorespiratory Medicine and Haematology, Clinical Sciences
Abstract

ObjectivesThis study sought to characterize ventricular tachycardia (VT) ablation outcomes across nonischemic cardiomyopathy (NICM) etiologies and adjust these outcomes by patient-related comorbidities that could explain differences in arrhythmia recurrence rates.BackgroundOutcomes of catheter ablation of VT in patients with NICM could be related to etiology of NICM.MethodsData from 2,075 patients with structural heart disease referred for catheter ablation of VT from 12 international centers was retrospectively analyzed. Patient characteristics and outcomes were noted for the 6 most common NICM etiologies. Multivariable Cox proportional hazards modeling was used to adjust for potential confounders.ResultsOf 780 NICM patients (57 ± 14 years of age, 18% women, left ventricular ejection fraction 37 ± 13%), underlying prevalence was 66% for dilated idiopathic cardiomyopathy (DICM), 13% for arrhythmogenic right ventricular cardiomyopathy (ARVC), 6% for valvular cardiomyopathy, 6% for myocarditis, 4% for hypertrophic cardiomyopathy, and 3% for sarcoidosis. One-year freedom from VT was 69%, and freedom from VT, heart transplantation, and death was 62%. On unadjusted competing risk analysis, VT ablation in ARVC demonstrated superior VT-free survival (82%) versus DICM (p ≤ 0.01). Valvular cardiomyopathy had the poorest unadjusted VT-free survival, at 47% (p < 0.01). After adjusting for comorbidities, including age, heart failure severity, ejection fraction, prior ablation, and antiarrhythmic medication use, myocarditis, ARVC, and DICM demonstrated similar outcomes, whereas hypertrophic cardiomyopathy, valvular cardiomyopathy, and sarcoidosis had the highest risk of VT recurrence.ConclusionsCatheter ablation of VT in NICM is effective. Etiology of NICM is a significant predictor of outcomes, with ARVC, myocarditis, and DICM having similar but superior outcomes to hypertrophic cardiomyopathy, valvular cardiomyopathy, and sarcoidosis, after adjusting for potential covariates.

Published
2018

34. Transition from Childhood Nocturnal Enuresis to Adult Nocturia: A Systematic Review and Meta-Analysis

Author

Gong S, Khosla L, Gong F, Kasarla N, Everaert K, Weiss J, and Kabarriti A

Subjects
luts, pediatric urology, incontinence, nocturnal polyuria, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Susan Gong,1 Lakshay Khosla,1 Fred Gong,1 Nikhil Kasarla,1 Karel Everaert,2 Jeffrey Weiss,1 Abdo Kabarriti1 1Department of Urology, State University of New York Downstate Health Sciences University, Brooklyn, NY, USA; 2Department of Uro-Gynecology, Ghent University Hospital, Ghent, BelgiumCorrespondence: Susan GongDepartment of Urology, State University of New York Downstate Health Sciences University, 450 Clarkson Ave., Brooklyn, NY, 11203, USATel +1 845-891-6642Email Susan.Gong@downstate.eduPurpose: Current literature has suggested a relationship between nocturnal enuresis (NE) in childhood and the development of nocturia later in life as both disorders have similar underlying etiologies, comorbidities, and treatments. The objective was to synthesize the available evidence on the association between childhood NE and later presentation of nocturia.Methods: PubMed, CINAHL, Scopus, and Google Scholar were searched for peer-reviewed studies published between January 1980 and April 2021. Case–control and cohort studies that reported on childhood NE and current nocturia were included. The PRISMA protocol was followed (PROSPERO ID: CRD42021256255). A random-effects model was applied to calculate the pooled odds ratio (OR) and 95% confidence interval (CI). Risk of bias was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria and with a funnel plot.Results: Of the 278 articles identified, 8 studies met inclusion criteria. The 6 case–control and 2 prospective cohort studies resulted in a total sample size of 26,070 participants. In a random-effect pooled analysis, childhood NE was significantly associated with the development of nocturia (OR: 1.75, 95% CI: 1.11– 2.40). Significant heterogeneity (I2 = 92.7%, p < 0.01) was identified among the included studies, which was reflected in an asymmetrical funnel plot. NE and nocturia have similar underlying etiologies of hormonal abnormalities, sleep disorders, physiological disorders, and psychological disorders.Conclusion: The history of childhood NE is significantly associated with nocturia later in life. The data in this meta-analysis support this transition and identify potential similarities between the two disorders. The sparse number of articles relevant to this topic is a strong indicator of the need for more work on this transition from childhood to maturity. More studies are warranted to further explore the association between NE and nocturia.Keywords: LUTS, pediatric urology, incontinence, nocturnal polyuria

Published
2021

37. An overview of the NIRSPEC upgrade for the Keck II telescope

Author

Martin, EC, Fitzgerald, MP, McLean, IS, Doppmann, G, Kassis, M, Aliado, T, Canfield, J, Johnson, C, Kress, E, Lanclos, K, Magnone, K, Sohn, JM, Wang, E, and Weiss, J

Subjects
Telescopes: Keck, Spectrometers: NIRSPEC, Infrared Instrumentation, Instruments: Upgrades, astro-ph.IM
Abstract

NIRSPEC is a 1-5 um echelle spectrograph in use on the Keck II Telescope since 1999. The spectrograph is capable of both moderate (R=λ/Δλ∼2000) and high (R∼25,000) resolution observations and has been a workhorse instrument across many astronomical fields, from planetary science to extragalactic observations. In the latter half of 2018, we will upgrade NIRSPEC to improve the sensitivity and stability of the instrument and increase its lifetime. The major components of the upgrade include replacing the spectrometer and slit-viewing camera detectors with Teledyne H2RG arrays and replacing all transputer-based electronics. We present detailed design, testing, and analysis of the upgraded instrument, including the finalized optomechanical design of the new 1-5 μm slit-viewing camera, detector characterization of the science and Engineering A grade arrays, electronics systems, and updated software design. The optomechanical design of the slit-viewing camera and replacement detector head assembly have both been assembled and cold-tested in our lab. We also show results from the GigE interface to the SAM/ASIC boards to control the H2RG. The upgrade will continue NIRSPEC's legacy as a powerful near-infrared spectrograph behind one of the world's most scientifically productive telescopes.

Published
2018

38. Racial Disparities and Achievement of the Low Lupus Disease Activity State: A CARRARegistry Study

Author

Soulsby, William Daniel, Olveda, Rebecca, He, Jie, Berbert, Laura, Weller, Edie, Barbour, Kamil E., Greenlund, Kurt J., Schanberg, Laura E., von Scheven, Emily, Hersh, Aimee, Son, Mary Beth F., Chang, Joyce, Knight, Andrea, Aamir, R., Abulaban, K., Adams, A., Aguiar Lapsia, C., Akinsete, A., Akoghlanian, S., Al Manaa, M., AlBijadi, A., Allenspach, E., Almutairi, A., Alperin, R., Amarilyo, G., Ambler, W., Amoruso, M., Angeles‐Han, S., Ardoin, S., Armendariz, S., Asfaw, L., Aviran Dagan, N., Bacha, C., Balboni, I., Balevic, S., Ballinger, S., Baluta, S., Barillas‐Arias, L., Basiaga, M., Baszis, K., Baxter, S., Becker, M., Begezda, A., Behrens, E., Beil, E., Benseler, S., Bermudez‐Santiago, L., Bernal, W., Bigley, T., Bingham, C., Binstadt, B., Black, C., Blackmon, B., Blakley, M., Bohnsack, J., Boneparth, A., Bradfield, H., Bridges, J., Brooks, E., Brothers, M., Brunner, H., Buckley, L., Buckley, M., Buckley, M., Bukulmez, H., Bullock, D., Canna, S., Cannon, L., Canny, S., Cartwright, V., Cassidy, E., Castro, D., Chalom, E., Chang, J., Chang, M., Chang, J., Chang‐Hoftman, A., Chen, A., Chiraseveenuprapund, P., Ciaglia, K., Co, D., Cohen, E., Collinge, J., Conlon, H., Connor, R., Cook, K., Cooper, A., Cooper, J., Corbin, K., Correll, C., Cron, R., Curry, M., Dalrymple, A., Datyner, E., Davis, T., De Ranieri, D., Dean, J., DeCoste, C., Dedeoglu, F., DeGuzman, M., Delnay, N., DeSantis, E., Devine, R., Dhalla, M., Dhanrajani, A., Dissanayake, D., Dizon, B., Drapeau, N., Drew, J., Driest, K., Du, Q., Duncan, E., Dunnock, K., Durkee, D., Dvergsten, J., Eberhard, A., Ede, K., Edelheit, B., Edens, C., El Tal, T., Elder, M., Elzaki, Y., Fadrhonc, S., Failing, C., Fair, D., Favier, L., Feldman, B., Fennell, J., Ferguson, P., Ferguson, I., Figueroa, C., Flanagan, E., Fogel, L., Fox, E., Fox, M., Franklin, L., Fuhlbrigge, R., Fuller, J., Furey, M., Futch‐West, T., Gagne, S., Gennaro, V., Gerstbacher, D., Gilbert, M., Gironella, A., Glaser, D., Goh, I., Goldsmith, D., Gorry, S., Goswami, N., Gottlieb, B., Graham, T., Grevich, S., Griffin, T., Grim, A., Grom, A., Guevara, M., Hahn, T., Halyabar, O., Hamda Natur, M., Hammelev, E., Hammond, T., Harel, L., Harris, J., Harry, O., Hausmann, J., Hay, A., Hays, K., Hayward, K., Henderson, L., Henrickson, M., Hersh, A., Hickey, K., Hiraki, L., Hiskey, M., Hobday, P., Hoffart, C., Holland, M., Hollander, M., Hong, S., Horton, D., Horwitz, M., Hsu, J., Huber, A., Huberts, A., Huggins, J., Huie, L., Hui‐Yuen, J., Ibarra, M., Imlay, A., Imundo, L., Inman, C., Jackson, A., James, K., Janow, G., Jared, S., Jiang, Y., Johnson, L., Johnson, N., Jones, J., Kafisheh, D., Kahn, P., Kaidar, K., Kasinathan, S., Kaur, R., Kessler, E., Kienzle, B., Kim, S., Kimura, Y., Kingsbury, D., Kitcharoensakkul, M., Klausmeier, T., Klein, K., Klein‐Gitelman, M., Knight, A., Kovalick, L., Kramer, S., Kremer, C., Kudas, O., LaFlam, T., Lang, B., Lapidus, S., Lapin, B., Lasky, A., Lawler, C., Lawson, E., Laxer, R., Lee, P., Lee, P., Lee, T., Lee, A., Leisinger, E., Lentini, L., Lerman, M., Levinsky, Y., Levy, D., Li, S., Lieberman, S., Lim, L., Limenis, E., Lin, C., Ling, N., Lionetti, G., Livny, R., Lloyd, M., Lo, M., Long, A., Lopez‐Peña, M., Lovell, D., Luca, N., Lvovich, S., Lytch, A., Ma, M., Machado, A., MacMahon, J., Madison, J., Mannion, M., Manos, C., Mansfield, L., Marston, B., Mason, T., Matchett, D., McAllister, L., McBrearty, K., McColl, J., McCurdy, D., McDaniels, K., McDonald, J., Meidan, E., Mellins, E., Mian, Z., Miettunen, P., Miller, M., Milojevic, D., Mitacek, R., Modica, R., Mohan, S., Moore, T., Moore, K., Moorthy, L., Moreno, J., Morgan, E., Moyer, A., Murante, B., Murphy, A., Muscal, E., Mwizerwa, O., Najafi, A., Nanda, K., Nasah, N., Nassi, L., Nativ, S., Natter, M., Nearanz, K., Neely, J., Newhall, L., Nguyen, A., Nigrovic, P., Nocton, J., Nolan, B., Nowicki, K., Oakes, R., Oberle, E., Ogbonnaya‐Whittesley, S., Ogbu, E., Oliver, M., Olveda, R., Onel, K., Orandi, A., Padam, J., Paller, A., Pan, N., Pandya, J., Panupattanapong, S., Pappo Toledano, A., Parsons, A., Patel, J., Patel, P., Patrick, A., Patrizi, S., Paul, S., Perfetto, J., Perron, M., Peskin, M., Ponder, L., Pooni, R., Prahalad, S., Puplava, B., Quinlan‐Waters, M., Rabinovich, C., Rafko, J., Rahimi, H., Rampone, K., Ramsey, S., Randell, R., Ray, L., Reed, A., Reed, A., Reid, H., Reiff, D., Richins, S., Riebschleger, M., Rife, E., Riordan, M., Riskalla, M., Robinson, A., Robinson, L., Rodgers, L., Rodriquez, M., Rogers, D., Ronis, T., Rosado, A., Rosenkranz, M., Rosenwasser, N., Rothermel, H., Rothman, D., Rothschild, E., Roth‐Wojcicki, E., Rouster‐Stevens, K., Rubinstein, T., Rupp, J., Ruth, N., Sabbagh, S., Sadun, R., Santiago, L., Saper, V., Sarkissian, A., Scalzi, L., Schahn, J., Schikler, K., Schlefman, A., Schmeling, H., Schmitt, E., Schneider, R., Schulert, G., Schultz, K., Schutt, C., Seper, C., Sheets, R., Shehab, A., Shenoi, S., Sherman, M., Shirley, J., Shishov, M., Siegel, D., Singer, N., Sivaraman, V., Sloan, E., Smith, C., Smith, J., Smitherman, E., Soep, J., Son, Mary B., Sosna, D., Spencer, C., Spiegel, L., Spitznagle, J., Srinivasalu, H., Stapp, H., Steigerwald, K., Stephens, A., Sterba Rakovchik, Y., Stern, S., Stevens, B., Stevenson, R., Stewart, K., Stewart, W., Stingl, C., Stoll, M., Stringer, E., Sule, S., Sullivan, J., Sundel, R., Sutter, M., Swaffar, C., Swayne, N., Syed, R., Symington, T., Syverson, G., Szymanski, A., Taber, S., Tal, R., Tambralli, A., Taneja, A., Tanner, T., Tarvin, S., Tate, L., Taxter, A., Taylor, J., Tesher, M., Thakurdeen, T., Theisen, A., Thomas, B., Thomas, L., Thomas, N., Ting, T., Todd, C., Toib, D., Toib, D., Torok, K., Tory, H., Toth, M., Tse, S., Tsin, C., Twachtman‐Bassett, J., Twilt, M., Valcarcel, T., Valdovinos, R., Vallee, A., Van Mater, H., Vandenbergen, S., Vannoy, L., Varghese, C., Vasquez, N., Vega‐Fernandez, P., Velez, J., Verbsky, J., Verstegen, R., Scheven, E., Vora, S., Wagner‐Weiner, L., Wahezi, D., Waite, H., Walker, B., Walters, H., Waterfield, M., Waters, A., Weiser, P., Weiss, P., Weiss, J., Wershba, E., Westheuser, V., White, A., Widrick, K., Williams, C., Wong, S., Woolnough, L., Wright, T., Wu, E., Yalcindag, A., Yasin, S., Yeung, R., Yomogida, K., Zeft, A., Zhang, Y., Zhao, Y., and Zhu, A.

Abstract

Differential disease control may contribute to racial disparities in outcomes of childhood‐onset systemic lupus erythematosus (cSLE). We evaluated associations of race and individual‐ or neighborhood‐level social determinants of health (SDoH) with achievement of low lupus disease activity state (LLDAS), a clinically relevant treatment target. In this cSLE cohort study using the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry, the primary exposure was self‐reported race and ethnicity, and collected SDoH included insurance status and area deprivation index (ADI). Outcomes included LLDAS, disease activity, and time‐averaged prednisone exposure. Associations among race and ethnicity, SDoH, and disease activity were estimated with multivariable regression models, adjusting for disease‐related and demographic factors. Among 540 children with cSLE, 27% identified as Black, 25% identified as White, 23% identified as Latino/a, 11% identified as Asian, 9% identified as more than one race, and 5% identified as other. More Black children (41%) lived in neighborhoods of highest ADI compared to White children (16%). Black race was associated with lower LLDAS achievement (adjusted odds ratio 0.56, 95% confidence interval [CI] 0.38–0.82) and higher disease activity (adjusted β 0.94, 95% CI 0.11–1.78). The highest ADI was not associated with lower LLDAS achievement on adjustment for renal disease and insurance. However, renal disease was found to be a significant mediator (P= 0.04) of the association between ADI and prednisone exposure. Children with cSLE who identified as Black are less likely to achieve LLDAS and have a higher disease activity. Living in areas of higher ADI may relate to renal disease and subsequent prednisone exposure. Strategies to address root causes will be important to design interventions mitigating cSLE racial disparities.

Published
2025
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41. Demonstration of an iron-pnictide bulk superconducting magnet capable of trapping over 1 T

Author

Weiss, J. D., Yamamoto, A., Polyanskii, A. A., Richardson, R. B., Larbalestier, D. C., and Hellstrom, E. E.

Subjects
Condensed Matter - Superconductivity
Abstract

A trapped field of over 1 T at 5 K and 0.5 T at 20 K has been measured between a stack of magnetized cylinders of bulk polycrystalline Ba0.6K0.4Fe2As2 superconductors 10 mm in diameter and 18 mm in combined thickness. The trapped field showed a low magnetic creep rate (~3% after 24 hours at 5 K), while magneto-optical imaging revealed a trapped field distribution corresponding to uniform macroscopic current loops circulating through the sample. The superconductors were manufactured by hot isostatic pressing of pre-reacted powders using the scalable powder-in-tube technique. A high Vickers hardness of ~3.5 GPa and a reasonable fracture toughness of ~2.35 MPa m0.5 were measured. Given the untextured polycrystalline nature of the cylinders and their large irreversibility field (> 90 T), it is expected that larger bulks could trap fields in excess of 10 T., Comment: 11 pages, 5 figures

Published
2015
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43. Rainfall, peak river flow and flow variability drive spatio‐temporal change in the extent of riparian woodland in an African protected area savanna.

Author

Weiss, J. A., Cramer, M. D., and Thompson, D. I.

Subjects
PLANT conservation, STREAMFLOW, VEGETATION dynamics, REMOTE-sensing images, FORESTS & forestry
Abstract

Verbal accounts, supported by limited ground‐based and satellite images, reveal decreasing riparian woodland and a loss of large trees along the rivers of the Kruger National Park (KNP, South Africa) over the last century. A multi‐decadal analysis was conducted to identify trends in extent and possible drivers of riparian woodland change. Aerial and satellite imagery (1936–2018) were used to quantify changes in the extent of riparian woodland at 18 sites on 14 rivers in KNP. These changes were compared in a multivariate time‐series with river flow and local rainfall. Particular attention was paid to cumulative flow effects, as well as the frequency and magnitude of large infrequent disturbances such as droughts and floods. Riparian tree cover fluctuated over the time period, and the trajectory of change varied between sites. Most (11) sites experienced a decrease in overall riparian tree cover over ~80 years, with these declines being significant at six sites. Peak flow and maximum rainfall events were strongly associated with these decreases, indicating that flood events are potentially the biggest driver of tree loss from the system. Indeed, the mega‐flood event of 2000 and subsequent large floods have resulted in substantial declines in riparian woodland extent in recent decades. Alternatively, flow variability and cumulative rainfall significantly influenced woodland expansion in isolated cases. With global change models predicting more erratic rainfall and an increased likelihood of large infrequent disturbances, together with increasing demands to abstract more water, the long‐term future of these dynamic habitats and their associated biota here is uncertain. [ABSTRACT FROM AUTHOR]

Published
2024
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44. On the low-frequency dynamics of turbulent separation bubbles.

Author

Cura, C., Hanifi, A., Cavalieri, A.V.G., and Weiss, J.

Subjects
BOUNDARY layer separation, MOTION capture (Human mechanics), LINEAR operators, SPECTRAL sensitivity, FLOW separation
Abstract

The low-frequency modal and non-modal linear dynamics of an incompressible, pressure-gradient-induced turbulent separation bubble (TSB) are investigated, with the objective of studying the mechanism responsible for the low-frequency contraction and expansion (breathing) commonly observed in experimental studies. The configuration of interest is a TSB generated on a flat test surface by a succession of adverse and favourable pressure gradients. The base flow selected for the analysis is the average TSB from the direct numerical simulation of Coleman et al. (J. Fluid Mech. , vol. 847, 2018, pp. 28–70). Global mode analysis reveals that the eigenmodes of the linear operator are damped for all frequencies and wavenumbers. Furthermore, the least damped eigenmode appears to occur at zero frequency and low, non-zero spanwise wavenumber when scaled with the separation length. Resolvent analysis is then employed to examine the forced dynamics of the flow. At low frequency, a region of low, non-zero spanwise wavenumber is also discernible, where the receptivity appears to be driven by the identified weakly damped global mode. The corresponding optimal energy gain is shown to have the shape of a first-order, low-pass filter with a cut-off frequency consistent with the low-frequency unsteadiness in TSBs. The results from resolvent analysis are compared to the unsteady experimental database of Le Floc'h et al. (J. Fluid Mech. , vol. 902, 2020, A13) in a similar TSB flow. The alignment between the optimal response and the first spectral proper orthogonal decomposition mode computed from the experiments is shown to be close to $95\,\%$ , while the spanwise wavenumber of the optimal response is consistent with that of the low-frequency breathing motion captured experimentally. This indicates that the fluctuations observed experimentally at low frequency closely match the response computed from resolvent analysis. Based on these results, we propose that the forced dynamics of the flow, driven by the weakly damped global mode, serve as a plausible mechanism for the origin of the low-frequency breathing motion commonly observed in experimental studies of TSBs. [ABSTRACT FROM AUTHOR]

Published
2024
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