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2. Singlet fission spin dynamics from molecular structure: a modular computational pipeline

Author

Jones, Dominic, MacDonald, Thomas, Schmidt, Timothy W., and McCamey, Dane R.

Subjects
Physics - Chemical Physics
Abstract

Singlet fission, which has applications in areas ranging form solar energy to quantum information, relies critically on transitions within a multi-spin manifold. These transitions are driven by fluctuations in the spin-spin exchange interaction, which have been linked to changes in nuclear geometry or exciton migration. Whilst simple calculations have supported this mechanism, to date little effort has been made to model realistic fluctuations which are informed by the actual structure and properties of physical materials. In this paper, we develop a modular computational pipeline for calculating singlet fission spin dynamics by way of electronic structural calculations, molecular dynamics, and numerical models of spin dynamics. The outputs of this pipeline aid in the interpretation of measured spin dynamics and allow us to place constraints on geometric fluctuations which are consistent with these observations., Comment: 23 pages (including SI), 7 Figures

Published
2023

4. Room Temperature Optically and Magnetically Active Edges in Phosphorene Nanoribbons

Author

Ashoka, Arjun, Clancy, Adam J., Panjwani, Naitik A., Popiel, Nicholas J. M., Eaton, Alex, Parton, Thomas G., Picco, Loren, Feldmann, Sascha, Shutt, Rebecca R. C., Carey, Remington, Aw, Eva S. Y., Macdonald, Thomas J., Severijnen, Marion E., Kleuskens, Sandra, de Aguiar, Hilton Barbosa, Friend, Richard H., Behrends, Jan, Christianen, Peter C. M., Howard, Christopher A., Rao, Akshay, and Pandya, Raj

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science
Abstract

Nanoribbons - nanometer wide strips of a two-dimensional material - are a unique system in condensed matter physics. They combine the exotic electronic structures of low-dimensional materials with an enhanced number of exposed edges, where phenomena including ultralong spin coherence times, quantum confinement and topologically protected states can emerge. An exciting prospect for this new material concept is the potential for both a tunable semiconducting electronic structure and magnetism along the nanoribbon edge. This combination of magnetism and semiconducting properties is the first step in unlocking spin-based electronics such as non-volatile transistors, a route to low-energy computing, and has thus far typically only been observed in doped semiconductor systems and/or at low temperatures. Here, we report the magnetic and semiconducting properties of phosphorene nanoribbons (PNRs). Static (SQUID) and dynamic (EPR) magnetization probes demonstrate that at room temperature, films of PNRs exhibit macroscopic magnetic properties, arising from their edge, with internal fields of ~ 250 to 800 mT. In solution, a giant magnetic anisotropy enables the alignment of PNRs at modest sub-1T fields. By leveraging this alignment effect, we discover that upon photoexcitation, energy is rapidly funneled to a dark-exciton state that is localized to the magnetic edge and coupled to a symmetry-forbidden edge phonon mode. Our results establish PNRs as a unique candidate system for studying the interplay of magnetism and semiconducting ground states at room temperature and provide a stepping-stone towards using low-dimensional nanomaterials in quantum electronics., Comment: 18 pages, 4 figures

Published
2022

8. Additive‐Free, Low‐Temperature Crystallization of Stable α‐FAPbI3 Perovskite

Author

Du, Tian, Macdonald, Thomas J, Yang, Ruo Xi, Li, Meng, Jiang, Zhongyao, Mohan, Lokeshwari, Xu, Weidong, Su, Zhenhuang, Gao, Xingyu, Whiteley, Richard, Lin, Chieh‐Ting, Min, Ganghong, Haque, Saif A, Durrant, James R, Persson, Kristin A, McLachlan, Martyn A, and Briscoe, Joe

Subjects
Macromolecular and Materials Chemistry, Chemical Sciences, Physical Chemistry, Engineering, Materials Engineering, additive-free, aerosol-assisted crystallization, formamidinium lead triiodide, stability, strain, Physical Sciences, Nanoscience & Nanotechnology, Chemical sciences, Physical sciences
Abstract

Formamidinium lead triiodide (FAPbI3 ) is attractive for photovoltaic devices due to its optimal bandgap at around 1.45 eV and improved thermal stability compared with methylammonium-based perovskites. Crystallization of phase-pure α-FAPbI3 conventionally requires high-temperature thermal annealing at 150 °C whilst the obtained α-FAPbI3 is metastable at room temperature. Here, aerosol-assisted crystallization (AAC) is reported, which converts yellow δ-FAPbI3 into black α-FAPbI3 at only 100 °C using precursor solutions containing only lead iodide and formamidinium iodide with no chemical additives. The obtained α-FAPbI3 exhibits remarkably enhanced stability compared to the 150 °C annealed counterparts, in combination with improvements in film crystallinity and photoluminescence yield. Using X-ray diffraction, X-ray scattering, and density functional theory simulation, it is identified that relaxation of residual tensile strains, achieved through the lower annealing temperature and post-crystallization crystal growth during AAC, is the key factor that facilitates the formation of phase-stable α-FAPbI3 . This overcomes the strain-induced lattice expansion that is known to cause the metastability of α-FAPbI3 . Accordingly, pure FAPbI3 p-i-n solar cells are reported, facilitated by the low-temperature (≤100 °C) AAC processing, which demonstrates increases of both power conversion efficiency and operational stability compared to devices fabricated using 150 °C annealed films.

Published
2022

10. Holding back the waters

Author

MacDonald, Thomas C.

Subjects
DISASTERS - Protection, DISASTER CONTROL, ENVIRONMENTAL PROTECTION, ARMY CORPS OF ENGINEERS
Abstract

illus

Published
2006

12. ACHIEVED SYSTOLIC BLOOD PRESSURE BELOW 130 MMHG PRESERVES KIDNEY FUNCTION IN DIABETIC AND NON-DIABETIC HYPERTENSIVE PATIENTS WITHOUT CARDIAC HYPERTROPHY

Author

Olsen, Eirik, primary, Soraas, Camilla L., additional, Schmieder, Roland E., additional, Jamerson, Kenneth, additional, Macdonald, Thomas, additional, Mancia, Giuseppe, additional, Heimark, Sondre, additional, Mehlum, Maria H., additional, Mariampillai, Julian, additional, Liestol, Knut, additional, Larstorp, Anne C, additional, Hoieggen, Aud, additional, Kjeldsen, Sverre E., additional, Rostrup, Morten, additional, Mo, Rune, additional, Julius, Stevo, additional, and Weber, Michael A., additional

Published
2024
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13. ACHIEVED SYSTOLIC BLOOD PRESSURE BELOW 130 MMHG PRESERVES KIDNEY FUNCTION IN HIGH-RISK HYPERTENSIVE PATIENTS WITHOUT CARDIAC HYPERTROPHY BUT WITH PROTEINURIA

Author

Olsen, Eirik, primary, Soraas, Camilla, additional, Schmieder, Roland, additional, Jamerson, Kenneth, additional, Macdonald, Thomas, additional, Mancia, Giuseppe, additional, Heimark, Sondre, additional, Mehlum, Maria H., additional, Mariampullai, Julian, additional, Liestol, Knut, additional, Larstorp, Anne C., additional, Hoieggen, Aud, additional, Kjeldsen, Sverre E., additional, Rostrup, Morten, additional, Mo, Rune, additional, Julius, Stevo, additional, and Weber, Michael A., additional

Published
2024
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14. Experimental Demonstration of Multiple Monoenergetic Gamma Radiography for Effective Atomic Number Identification in Cargo Inspection

Author

Henderson, Brian S., Lee, Hin Y., MacDonald, Thomas D., Nelson, Roberts G., and Danagoulian, Areg

Subjects
Physics - Instrumentation and Detectors, Physics - Physics and Society
Abstract

The smuggling of special nuclear materials (SNM) through international borders could enable nuclear terrorism and constitutes a significant threat to global security. This paper presents the experimental demonstration of a novel radiographic technique for quantitatively reconstructing the density and type of material present in commercial cargo containers, as a means of detecting such threats. Unlike traditional techniques which use sources of bremsstrahlung photons with a continuous distribution of energies, multiple monoenergetic gamma radiography (MMGR) utilizes monoenergetic photons from nuclear reactions, specifically the 4.4 and 15.1 MeV photons from the $^{11}$B(d,n$\gamma$)$^{12}$C reaction. By exploiting the $Z$-dependence of the photon interaction cross sections at these two specific energies it is possible to simultaneously determine the areal density and the effective atomic number as a function of location for a 2D projection of a scanned object. The additional information gleaned from using and detecting photons of specific energies for radiography substantially increases the resolving power between different materials. This paper presents results from the imaging of mock cargo materials ranging from $Z\approx5$--$92$, demonstrating accurate reconstruction of the effective atomic number and areal density of the materials over the full range. In particular, the system is capable of distinguishing pure materials with $Z\gtrsim70$, such as lead and uranium --- a critical requirement of a system designed to detect SNM. This methodology could be used to screen commercial cargoes with high material specificity, to distinguish most benign materials from SNM, such as uranium and plutonium., Comment: 15 pages, 12 figures, version 2 includes language/typographical edits and changes (chiefly additions) in response to reviewers

Published
2018
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15. Helicobacter pylori eradication for primary prevention of peptic ulcer bleeding in older patients prescribed aspirin in primary care (HEAT): a randomised, double-blind, placebo-controlled trial

Author

Mant, David CA, Ford, Alexander C, Macdonald, Thomas M, Bradburn, Mike, Klauza, Claire A, Shone, Angela, Logan, Richard FA, Deeks, Jonathan J, McColl, Kenneth E.L., Goddard, Andrew F, Stevens, Richard, Sami, Sarned, Haughney, John, Cupples, Margaret E, Morar, Monique, O'Brien, Wendy, Hawkey, Chris, Avery, Anthony, Coupland, Carol A C, Crooks, Colin, Dumbleton, Jennifer, Hobbs, F D Richard, Kendrick, Denise, Moore, Michael, Morris, Clive, Rubin, Gregory, Smith, Murray, and Stevenson, Diane

Published
2022
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16. Cardiovascular outcomes in adults with hypertension with evening versus morning dosing of usual antihypertensives in the UK (TIME study): a prospective, randomised, open-label, blinded-endpoint clinical trial

Author

Mackenzie, Isla S, Rogers, Amy, Poulter, Neil R, Williams, Bryan, Brown, Morris J, Webb, David J, Ford, Ian, Rorie, David A, Guthrie, Greg, Grieve, J W Kerr, Pigazzani, Filippo, Rothwell, Peter M, Young, Robin, McConnachie, Alex, Struthers, Allan D, Lang, Chim C, and MacDonald, Thomas M

Published
2022
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17. Allopurinol versus usual care in UK patients with ischaemic heart disease (ALL-HEART): a multicentre, prospective, randomised, open-label, blinded-endpoint trial

Author

Ahmed, Husnat, Arthur, Peter, Aziz, Jane, Barnes, Lawrence, Boyle, Sarah, Brighton, Tom, Brown, Morris, Caulfield, Mark, Dawson, Jesse, Denvir, Martin, Doney, Alexander SF, Doshi, Sagar, Dryburgh, Moira, Eddleston, Michael, Finlayson, Jim, Fuat, Ahmet, Furnace, Jacqueline, Grieve, JW Kerr, Guthrie, Greg, Ham, Sharon, Isaard, Emma, Jennings, Claudine, Johnson, Richard, Kerr, Claire, Khan, Sohail, Krishnan, Kailash, Long, Susan, Mackintosh, Anne, Macleod, Mary Joan, McCormack, Terry, McEleny, Paul, Morar, Monique, Nadir, Adnan, Newby, David, Petrie, Colin, Preiss, David, Ralston, Stuart, Randall, Marc, Routledge, Helen, Shakir, Saad, Sharma, Raj, Shepherd, Bridget, Sims, Don, Snedden, Gordon, Trevelyan, Jasper, Weir, Christopher, Weir, Robin, Wetherall, Kirsty, Wilson, Robbie, Wilson, Adam, Zutis, Kris, Mackenzie, Isla S, Hawkey, Christopher J, Ford, Ian, Greenlaw, Nicola, Pigazzani, Filippo, Rogers, Amy, Struthers, Allan D, Begg, Alan G, Wei, Li, Avery, Anthony J, Taggar, Jaspal S, Walker, Andrew, Duce, Suzanne L, Barr, Rebecca J, Dumbleton, Jennifer S, Rooke, Evelien D, Townend, Jonathan N, Ritchie, Lewis D, and MacDonald, Thomas M

Published
2022
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21. Analysis of the impact of sex and age on the variation in the prevalence of antinuclear autoantibodies in Polish population: a nationwide observational, cross-sectional study

Author

Krzemień, Paweł, Kasperczyk, Sławomir, Banach, Maciej, Kasperczyk, Aleksandra, Dobrakowski, Michał, Tomasik, Tomasz, Windak, Adam, Mastej, Mirosław, Catapano, Alberico, Ray, Kausik K., Mikhailidis, Dimitri P., Toth, Peter P., Howard, George, Lip, Gregory Y. H., Tomaszewski, Maciej, Charchar, Fadi J., Sattar, Naveed, Williams, Bryan, MacDonald, Thomas M., Penson, Peter E., and Jóźwiak, Jacek J.

Published
2022
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24. Interleukin-22 regulates neutrophil recruitment in ulcerative colitis and is associated with resistance to ustekinumab therapy

Author

Pavlidis, Polychronis, Tsakmaki, Anastasia, Pantazi, Eirini, Li, Katherine, Cozzetto, Domenico, Digby- Bell, Jonathan, Yang, Feifei, Lo, Jonathan W., Alberts, Elena, Sa, Ana Caroline Costa, Niazi, Umar, Friedman, Joshua, Long, Anna K., Ding, Yuchun, Carey, Christopher D., Lamb, Christopher, Saqi, Mansoor, Madgwick, Matthew, Gul, Leila, Treveil, Agatha, Korcsmaros, Tamas, Macdonald, Thomas T., Lord, Graham M., Bewick, Gavin, and Powell, Nick

Published
2022
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25. UMOD Genotype-Blinded Trial of Ambulatory Blood Pressure Response to Torasemide.

Author

McCallum, Linsay, Lip, Stefanie, McConnachie, Alex, Brooksbank, Katriona, MacIntyre, Iain M., Doney, Alexander, Llano, Andrea, Aman, Alisha, Caparrotta, Thomas M., Ingram, Gareth, Mackenzie, Isla S., Dominiczak, Anna F., MacDonald, Thomas M., Webb, David J., and Padmanabhan, Sandosh

Abstract

BACKGROUND: UMOD (uromodulin) has been linked to hypertension through potential activation of Na+-K+-2Cl- cotransporter (NKCC2), a target of loop diuretics. We posited that hypertensive patients carrying the rs13333226-AA UMOD genotype would demonstrate greater blood pressure responses to loop diuretics, potentially mediated by this UMOD/NKCC2 interaction. METHODS: This prospective, multicenter, genotype-blinded trial evaluated torasemide (torsemide) efficacy on systolic blood pressure (SBP) reduction over 16 weeks in nondiabetic, hypertensive participants uncontrolled on ≥1 nondiuretic antihypertensive for >3 months. The primary end point was the change in 24-hour ambulatory SBP (ABPM SBP) and SBP response trajectories between baseline and 16 weeks by genotype (AA versus AG/GG) due to nonrandomized groups at baseline (ClinicalTrials.gov: NCT03354897). RESULTS: Of 251 enrolled participants, 222 received torasemide and 174 demonstrated satisfactory treatment adherence and had genotype data. The study participants were middle-aged (59±11 years), predominantly male (62%), obese (body mass index, 32±7 kg/m²), with normal eGFR (92±17 mL/min/1.73 m²) and an average baseline ABPM of 138/81 mm Hg. Significant reductions in mean ABPM SBP were observed in both groups after 16 weeks (AA, -6.57 mm Hg [95% CI, -8.44 to -4.69]; P<0.0001; AG/GG, -3.22 [95% CI, -5.93 to -0.51]; P=0.021). The change in mean ABPM SBP (baseline to 16 weeks) showed a difference of -3.35 mm Hg ([95% CI, -6.64 to -0.05]; P=0.048) AA versus AG/GG genotypes. The AG/GG group displayed a rebound in SBP from 8 weeks, differing from the consistent decrease in the AA group (P=0.004 for difference in trajectories). CONCLUSIONS: Our results confirm a plausible interaction between UMOD and NKCC2 and suggest a potential role for genotype-guided use of loop diuretics in hypertension management. [ABSTRACT FROM AUTHOR]

Published
2024
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28. Allopurinol and cardiovascular outcomes in patients with ischaemic heart disease: the ALL-HEART RCT and economic evaluation

Author

Mackenzie, Isla S, primary, Hawkey, Christopher J, additional, Ford, Ian, additional, Greenlaw, Nicola, additional, Pigazzani, Filippo, additional, Rogers, Amy, additional, Struthers, Allan D, additional, Begg, Alan G, additional, Wei, Li, additional, Avery, Anthony J, additional, Taggar, Jaspal S, additional, Walker, Andrew, additional, Duce, Suzanne L, additional, Barr, Rebecca J, additional, Dumbleton, Jennifer S, additional, Rooke, Evelien D, additional, Townend, Jonathan N, additional, Ritchie, Lewis D, additional, and MacDonald, Thomas M, additional

Published
2024
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30. Overcoming Microstructural Defects at the Buried Interface of Formamidinium-Based Perovskite Solar Cells

Author

Lin, Heng-Yi, Jiang, Zhongyao, Liu, Shi-Chun, Du, Zhaoyi, Hsu, Shih-En, Li, Yun-Shan, Qiu, Wei-Jia, Yang, Hongta, Macdonald, Thomas J., McLachlan, Martyn A., and Lin, Chieh-Ting

Abstract

Since the advent of formamidinium (FA)-based perovskite photovoltaics (PVs), significant performance enhancements have been achieved. However, a critical challenge persists: the propensity for void formation in the perovskite film at the buried perovskite–interlayer interface has a deleterious effect on device performance. With most emerging perovskite PVs adopting the p-i-n architecture, the specific challenge lies at the perovskite–hole transport layer (HTL) interface, with previous strategies to overcome this limitation being limited to specific perovskite–HTL combinations; thus, the lack of universal approaches represents a bottleneck. Here, we present a novel strategy that overcomes the formation of such voids (microstructural defects) through a film treatment with methylammonium chloride (MACl). Specifically, our work introduces MACl via a sequential deposition method, having a profound impact on the microstructural defect density at the critical buried interface. Our technique is independent of both the HTL and the perovskite film thickness, highlighting the universal nature of this approach. By employing device photoluminescence measurements and conductive atomic force microscopy, we reveal that when present, such voids impede charge extraction, thereby diminishing device short-circuit current. Through comprehensive steady-state and transient photoluminescence spectroscopy analysis, we demonstrate that by implementing our MACl treatment to remedy these voids, devices with reduced defect states, suppressed nonradiative recombination, and extended carrier lifetimes of up to 2.3 μs can be prepared. Furthermore, our novel treatment reduces the stringent constraints around antisolvent choice and dripping time, significantly extending the processing window for the perovskite absorber layer and offering significantly greater flexibility for device fabrication.

Published
2024
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31. Eleven-year-old boy dies after being struck by puck during hockey practice in Quebec

Author

MacDonald, Thomas

Subjects
Hockey players -- Death of -- Investigations, Junior hockey -- Accidents -- Investigations, Company legal issue, General interest, News, opinion and commentary
Abstract

Byline: THOMAS MacDONALD; THE CANADIAN PRESS ST-EUSTACHE, QUE. -- An 11-year-old boy has died after getting hit in the neck by a puck during a junior hockey league practice near [...]

Published
2023

34. Bedtime dosing of antihypertensive medications: systematic review and consensus statement: International Society of Hypertension position paper endorsed by World Hypertension League and European Society of Hypertension

Author

Stergiou, George, Brunström, Mattias, MacDonald, Thomas, Kyriakoulis, Konstantinos G., Bursztyn, Michael, Khan, Nadia, Bakris, George, Kollias, Anastasios, Menti, Ariadni, Muntner, Paul, Orias, Marcelo, Poulter, Neil, Shimbo, Daichi, Williams, Bryan, Adeoye, Abiodun Moshood, Damasceno, Albertino, Korostovtseva, Lyudmila, Li, Yan, Muxfeldt, Elizabeth, Zhang, Yuqing, Mancia, Giuseppe, Kreutz, Reinhold, and Tomaszewski, Maciej

Published
2022
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37. Highly reproducible self-assembled monolayer based perovskite solar cells via amphiphilic polyelectrolyte

Author

Liu, Shi-Chun, primary, Lin, Heng-Yi, additional, Hsu, Shih-En, additional, Wu, Dong-Tai, additional, Sathasivam, Sanjayan, additional, Daboczi, Matyas, additional, Hsieh, Hsing-Jung, additional, Zeng, Chin-Sian, additional, Hsu, Ting-Ge, additional, Eslava, Salvador, additional, Macdonald, Thomas J., additional, and Lin, Chieh-Ting, additional

Published
2024
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46. The Food Additive Maltodextrin Promotes Endoplasmic Reticulum Stress–Driven Mucus Depletion and Exacerbates Intestinal Inflammation

Author

Laudisi, Federica, Di Fusco, Davide, Dinallo, Vincenzo, Stolfi, Carmine, Di Grazia, Antonio, Marafini, Irene, Colantoni, Alfredo, Ortenzi, Angela, Alteri, Claudia, Guerrieri, Francesca, Mavilio, Maria, Ceccherini-Silberstein, Francesca, Federici, Massimo, MacDonald, Thomas Thornton, Monteleone, Ivan, and Monteleone, Giovanni

Published
2019
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47. Unraveling Triplet Formation Mechanisms in Acenothiophene Chromophores

Author

He, Guiying, primary, Parenti, Kaia R., additional, Budden, Peter J., additional, Niklas, Jens, additional, Macdonald, Thomas, additional, Kumarasamy, Elango, additional, Chen, Xing, additional, Yin, Xiaodong, additional, McCamey, Dane R., additional, Poluektov, Oleg G., additional, Campos, Luis M., additional, and Sfeir, Matthew Y., additional

Published
2023
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48. Professor Gordon T. McInnes

Author

Brady, Adrian J.B., primary, Jardine, Alan, additional, MacDonald, Thomas M., additional, Heagerty, Anthony M., additional, Grassi, Guido, additional, and Mancia, Giuseppe, additional

Published
2023
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50. Production of Magnetic Arsenic–Phosphorus Alloy Nanoribbons with Small Band Gaps and High Hole Conductivities

Author

Zhang, Feng Fei, primary, Aw, Eva, additional, Eaton, Alexander G., additional, Shutt, Rebecca R. C., additional, Lim, Juhwan, additional, Kim, Jung Ho, additional, Macdonald, Thomas J., additional, Reyes, Cesar III D. L., additional, Ashoka, Arjun, additional, Pandya, Raj, additional, Payton, Oliver D., additional, Picco, Loren, additional, Knapp, Caroline E., additional, Corà, Furio, additional, Rao, Akshay, additional, Howard, Christopher A., additional, and Clancy, Adam J., additional

Published
2023
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