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Affortit P, Ahmed MA, Grondin A, Delzon S, Carminati A, Laplaze L. Keep in touch: the soil-root hydraulic continuum and its role in drought resistance in crops. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:584-593. [PMID: 37549338 DOI: 10.1093/jxb/erad312] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 08/04/2023] [Indexed: 08/09/2023]
Abstract
Drought is a major threat to food security worldwide. Recently, the root-soil interface has emerged as a major site of hydraulic resistance during water stress. Here, we review the impact of soil drying on whole-plant hydraulics and discuss mechanisms by which plants can adapt by modifying the properties of the rhizosphere either directly or through interactions with the soil microbiome.
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Affiliation(s)
- Pablo Affortit
- DIADE, IRD, CIRAD, Université de Montpellier, Montpellier, France
| | - Mutez Ali Ahmed
- Root-Soil Interaction, School of Life Science, Technical University of Munich, Freising, Germany
| | | | | | - Andrea Carminati
- Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland
| | - Laurent Laplaze
- DIADE, IRD, CIRAD, Université de Montpellier, Montpellier, France
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2
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Zhang P, Huang J, Ma Y, Wang X, Kang M, Song Y. Crop/Plant Modeling Supports Plant Breeding: II. Guidance of Functional Plant Phenotyping for Trait Discovery. PLANT PHENOMICS (WASHINGTON, D.C.) 2023; 5:0091. [PMID: 37780969 PMCID: PMC10538623 DOI: 10.34133/plantphenomics.0091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 08/26/2023] [Indexed: 10/03/2023]
Abstract
Observable morphological traits are widely employed in plant phenotyping for breeding use, which are often the external phenotypes driven by a chain of functional actions in plants. Identifying and phenotyping inherently functional traits for crop improvement toward high yields or adaptation to harsh environments remains a major challenge. Prediction of whole-plant performance in functional-structural plant models (FSPMs) is driven by plant growth algorithms based on organ scale wrapped up with micro-environments. In particular, the models are flexible for scaling down or up through specific functions at the organ nexus, allowing the prediction of crop system behaviors from the genome to the field. As such, by virtue of FSPMs, model parameters that determine organogenesis, development, biomass production, allocation, and morphogenesis from a molecular to the whole plant level can be profiled systematically and made readily available for phenotyping. FSPMs can provide rich functional traits representing biological regulatory mechanisms at various scales in a dynamic system, e.g., Rubisco carboxylation rate, mesophyll conductance, specific leaf nitrogen, radiation use efficiency, and source-sink ratio apart from morphological traits. High-throughput phenotyping such traits is also discussed, which provides an unprecedented opportunity to evolve FSPMs. This will accelerate the co-evolution of FSPMs and plant phenomics, and thus improving breeding efficiency. To expand the great promise of FSPMs in crop science, FSPMs still need more effort in multiscale, mechanistic, reproductive organ, and root system modeling. In summary, this study demonstrates that FSPMs are invaluable tools in guiding functional trait phenotyping at various scales and can thus provide abundant functional targets for phenotyping toward crop improvement.
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Affiliation(s)
- Pengpeng Zhang
- School of Agronomy, Anhui Agricultural University, Hefei, Anhui Province 230036, China
| | - Jingyao Huang
- School of Agronomy, Anhui Agricultural University, Hefei, Anhui Province 230036, China
| | - Yuntao Ma
- College of Land Science and Technology, China Agricultural University, Beijing 100094, China
| | - Xiujuan Wang
- The State Key Laboratory for Management and Control of Complex Systems, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
| | - Mengzhen Kang
- The State Key Laboratory for Management and Control of Complex Systems, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
| | - Youhong Song
- School of Agronomy, Anhui Agricultural University, Hefei, Anhui Province 230036, China
- Centre for Crop Science, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, QLD 4350, Australia
- Centre for Crop Science, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, QLD 4350, Australia
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3
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Selzner T, Horn J, Landl M, Pohlmeier A, Helmrich D, Huber K, Vanderborght J, Vereecken H, Behnke S, Schnepf A. 3D U-Net Segmentation Improves Root System Reconstruction from 3D MRI Images in Automated and Manual Virtual Reality Work Flows. PLANT PHENOMICS (WASHINGTON, D.C.) 2023; 5:0076. [PMID: 37519934 PMCID: PMC10381537 DOI: 10.34133/plantphenomics.0076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 07/10/2023] [Indexed: 08/01/2023]
Abstract
Magnetic resonance imaging (MRI) is used to image root systems grown in opaque soil. However, reconstruction of root system architecture (RSA) from 3-dimensional (3D) MRI images is challenging. Low resolution and poor contrast-to-noise ratios (CNRs) hinder automated reconstruction. Hence, manual reconstruction is still widely used. Here, we evaluate a novel 2-step work flow for automated RSA reconstruction. In the first step, a 3D U-Net segments MRI images into root and soil in super-resolution. In the second step, an automated tracing algorithm reconstructs the root systems from the segmented images. We evaluated the merits of both steps for an MRI dataset of 8 lupine root systems, by comparing the automated reconstructions to manual reconstructions of unaltered and segmented MRI images derived with a novel virtual reality system. We found that the U-Net segmentation offers profound benefits in manual reconstruction: reconstruction speed was doubled (+97%) for images with low CNR and increased by 27% for images with high CNR. Reconstructed root lengths were increased by 20% and 3%, respectively. Therefore, we propose to use U-Net segmentation as a principal image preprocessing step in manual work flows. The root length derived by the tracing algorithm was lower than in both manual reconstruction methods, but segmentation allowed automated processing of otherwise not readily usable MRI images. Nonetheless, model-based functional root traits revealed similar hydraulic behavior of automated and manual reconstructions. Future studies will aim to establish a hybrid work flow that utilizes automated reconstructions as scaffolds that can be manually corrected.
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Affiliation(s)
- Tobias Selzner
- Forschungszentrum Juelich GmbH, Agrosphere (IBG-3), Juelich, Germany
| | - Jannis Horn
- Autonomous Intelligence Systems Group,
University of Bonn, Bonn, Germany
| | - Magdalena Landl
- Forschungszentrum Juelich GmbH, Agrosphere (IBG-3), Juelich, Germany
| | - Andreas Pohlmeier
- Forschungszentrum Juelich GmbH, Agrosphere (IBG-3), Juelich, Germany
| | - Dirk Helmrich
- Forschungszentrum Juelich GmbH, Juelich Supercomputing Center, Juelich, Germany
| | - Katrin Huber
- Forschungszentrum Juelich GmbH, Agrosphere (IBG-3), Juelich, Germany
| | - Jan Vanderborght
- Forschungszentrum Juelich GmbH, Agrosphere (IBG-3), Juelich, Germany
| | - Harry Vereecken
- Forschungszentrum Juelich GmbH, Agrosphere (IBG-3), Juelich, Germany
| | - Sven Behnke
- Autonomous Intelligence Systems Group,
University of Bonn, Bonn, Germany
| | - Andrea Schnepf
- Forschungszentrum Juelich GmbH, Agrosphere (IBG-3), Juelich, Germany
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4
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Yu Q, Wang J, Tang H, Zhang J, Zhang W, Liu L, Wang N. Application of Improved UNet and EnglightenGAN for Segmentation and Reconstruction of In Situ Roots. PLANT PHENOMICS (WASHINGTON, D.C.) 2023; 5:0066. [PMID: 37426692 PMCID: PMC10325669 DOI: 10.34133/plantphenomics.0066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 06/14/2023] [Indexed: 07/11/2023]
Abstract
The root is an important organ for crops to absorb water and nutrients. Complete and accurate acquisition of root phenotype information is important in root phenomics research. The in situ root research method can obtain root images without destroying the roots. In the image, some of the roots are vulnerable to soil shading, which severely fractures the root system and diminishes its structural integrity. The methods of ensuring the integrity of in situ root identification and establishing in situ root image phenotypic restoration remain to be explored. Therefore, based on the in situ root image of cotton, this study proposes a root segmentation and reconstruction strategy, improves the UNet model, and achieves precise segmentation. It also adjusts the weight parameters of EnlightenGAN to achieve complete reconstruction and employs transfer learning to implement enhanced segmentation using the results of the former two. The research results show that the improved UNet model has an accuracy of 99.2%, mIOU of 87.03%, and F1 of 92.63%. The root reconstructed by EnlightenGAN after direct segmentation has an effective reconstruction ratio of 92.46%. This study enables a transition from supervised to unsupervised training of root system reconstruction by designing a combination strategy of segmentation and reconstruction network. It achieves the integrity restoration of in situ root system pictures and offers a fresh approach to studying the phenotypic of in situ root systems, also realizes the restoration of the integrity of the in situ root image, and provides a new method for in situ root phenotype study.
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Affiliation(s)
- Qiushi Yu
- College of Mechanical and Electrical Engineering,
Hebei Agricultural University, 071000, Baoding, China
| | - Jingqi Wang
- College of Mechanical and Electrical Engineering,
Hebei Agricultural University, 071000, Baoding, China
| | - Hui Tang
- College of Mechanical and Electrical Engineering,
Hebei Agricultural University, 071000, Baoding, China
| | - Jiaxi Zhang
- College of Mechanical and Electrical Engineering,
Hebei Agricultural University, 071000, Baoding, China
| | - Wenjie Zhang
- College of Mechanical and Electrical Engineering,
Hebei Agricultural University, 071000, Baoding, China
| | - Liantao Liu
- College of Agronomy,
Hebei Agricultural University, 071000, Baoding, China
| | - Nan Wang
- College of Mechanical and Electrical Engineering,
Hebei Agricultural University, 071000, Baoding, China
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5
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Meunier F, Couvreur V, Draye X, Lobet G, Huber K, Schroeder N, Jorda H, Koch A, Landl M, Schnepf A, Vanderborght J, Vereecken H, Javaux M. Investigating Soil-Root Interactions with the Numerical Model R-SWMS. Methods Mol Biol 2022; 2395:259-283. [PMID: 34822158 DOI: 10.1007/978-1-0716-1816-5_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
In this chapter, we present the Root and Soil Water Movement and Solute transport model R-SWMS, which can be used to simulate flow and transport in the soil-plant system. The equations describing water flow in soil-root systems are presented and numerical solutions are provided. An application of R-SWMS is then briefly discussed, in which we combine in vivo and in silico experiments in order to decrypt water flow in the soil-root domain. More precisely, light transmission imaging experiments were conducted to generate data that can serve as input for the R-SWMS model. These data include the root system architecture, the soil hydraulic properties and the environmental conditions (initial soil water content and boundary conditions, BC). Root hydraulic properties were not acquired experimentally, but set to theoretical values found in the literature. In order to validate the results obtained by the model, the simulated and experimental water content distributions were compared. The model was then used to estimate variables that were not experimentally accessible, such as the actual root water uptake distribution and xylem water potential.
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Affiliation(s)
- Félicien Meunier
- Earth and Life Institute/Environmental Sciences, Université catholique de Louvain, Louvain, Belgium
| | - Valentin Couvreur
- Earth and Life Institute/Environmental Sciences, Université catholique de Louvain, Louvain, Belgium
| | - Xavier Draye
- Earth and Life Institute/Environmental Sciences, Université catholique de Louvain, Louvain, Belgium
| | - Guillaume Lobet
- Earth and Life Institute/Environmental Sciences, Université catholique de Louvain, Louvain, Belgium
- Agrosphere (IBG-3), Forschungszentrum Juelich GmbH, Jülich, Germany
| | - Katrin Huber
- Agrosphere (IBG-3), Forschungszentrum Juelich GmbH, Jülich, Germany
| | - Nathalie Schroeder
- Earth and Life Institute/Environmental Sciences, Université catholique de Louvain, Louvain, Belgium
- Department of Hydromechanics and Modelling of Hydrosystems, University of Stuttgart, Stuttgart, Germany
| | - Helena Jorda
- Agrosphere (IBG-3), Forschungszentrum Juelich GmbH, Jülich, Germany
| | - Axelle Koch
- Earth and Life Institute/Environmental Sciences, Université catholique de Louvain, Louvain, Belgium
| | - Magdalena Landl
- Agrosphere (IBG-3), Forschungszentrum Juelich GmbH, Jülich, Germany
| | - Andrea Schnepf
- Agrosphere (IBG-3), Forschungszentrum Juelich GmbH, Jülich, Germany
| | - Jan Vanderborght
- Agrosphere (IBG-3), Forschungszentrum Juelich GmbH, Jülich, Germany
| | - Harry Vereecken
- Agrosphere (IBG-3), Forschungszentrum Juelich GmbH, Jülich, Germany
| | - Mathieu Javaux
- Earth and Life Institute/Environmental Sciences, Université catholique de Louvain, Louvain, Belgium.
- Agrosphere (IBG-3), Forschungszentrum Juelich GmbH, Jülich, Germany.
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6
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He F, Steige KA, Kovacova V, Göbel U, Bouzid M, Keightley PD, Beyer A, de Meaux J. Cis-regulatory evolution spotlights species differences in the adaptive potential of gene expression plasticity. Nat Commun 2021; 12:3376. [PMID: 34099660 PMCID: PMC8184852 DOI: 10.1038/s41467-021-23558-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 04/29/2021] [Indexed: 11/09/2022] Open
Abstract
Phenotypic plasticity is the variation in phenotype that a single genotype can produce in different environments and, as such, is an important component of individual fitness. However, whether the effect of new mutations, and hence evolution, depends on the direction of plasticity remains controversial. Here, we identify the cis-acting modifications that have reshaped gene expression in response to dehydration stress in three Arabidopsis species. Our study shows that the direction of effects of most cis-regulatory variants differentiating the response between A. thaliana and the sister species A. lyrata and A. halleri depends on the direction of pre-existing plasticity in gene expression. A comparison of the rate of cis-acting variant accumulation in each lineage indicates that the selective forces driving adaptive evolution in gene expression favors regulatory changes that magnify the stress response in A. lyrata. The evolutionary constraints measured on the amino-acid sequence of these genes support this interpretation. In contrast, regulatory changes that mitigate the plastic response to stress evolved more frequently in A. halleri. Our results demonstrate that pre-existing plasticity may be a stepping stone for adaptation, but its selective remodeling differs between lineages.
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Affiliation(s)
- F He
- CEPLAS, University of Cologne, Cologne, Germany
| | - K A Steige
- CEPLAS, University of Cologne, Cologne, Germany
| | - V Kovacova
- CECAD, University of Cologne, Cologne, Germany
| | - U Göbel
- CEPLAS, University of Cologne, Cologne, Germany
| | - M Bouzid
- CEPLAS, University of Cologne, Cologne, Germany
| | - P D Keightley
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
| | - A Beyer
- CEPLAS, University of Cologne, Cologne, Germany
| | - J de Meaux
- CEPLAS, University of Cologne, Cologne, Germany.
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7
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De Bauw P, Mai TH, Schnepf A, Merckx R, Smolders E, Vanderborght J. A functional-structural model of upland rice root systems reveals the importance of laterals and growing root tips for phosphate uptake from wet and dry soils. ANNALS OF BOTANY 2020; 126:789-806. [PMID: 32597468 PMCID: PMC7489101 DOI: 10.1093/aob/mcaa120] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 06/22/2020] [Indexed: 05/22/2023]
Abstract
BACKGROUND AND AIMS Upland rice is often grown where water and phosphorus (P) are limited. To better understand the interaction between water and P availability, functional-structural models that mechanistically represent small-scale nutrient gradients and water dynamics in the rhizosphere are needed. METHODS Rice was grown in large columns using a P-deficient soil at three P supplies in the topsoil (deficient, sub-optimal and non-limiting) in combination with two water regimes (field capacity vs. drying periods). Root system characteristics, such as nodal root number, lateral types, interbranch distance, root diameters and the distribution of biomass with depth, as well as water and P uptake, were measured. Based on the observed root data, 3-D root systems were reconstructed by calibrating the structural architecure model CRootBox for each scenario. Water flow and P transport in the soil to each of the individual root segments of the generated 3-D root architectures were simulated using a multiscale flow and transport model. Total water and P uptake were then computed by adding up the uptake by all the root segments. KEY RESULTS Measurements showed that root architecture was significantly affected by the treatments. The moist, high P scenario had 2.8 times the root mass, double the number of nodal roots and more S-type laterals than the dry, low P scenario. Likewise, measured plant P uptake increased >3-fold by increasing P and water supply. However, drying periods reduced P uptake at high but not at low P supply. Simulation results adequately predicted P uptake in all scenarios when the Michaelis-Menten constant (Km) was corrected for diffusion limitation. They showed that the key drivers for P uptake are the different types of laterals (i.e. S- and L-type) and growing root tips. The L-type laterals become more important for overall water and P uptake than the S-type laterals in the dry scenarios. This is true across all the P treatments, but the effect is more pronounced as the P availability decreases. CONCLUSIONS This functional-structural model can predict the function of specific rice roots in terms of P and water uptake under different P and water supplies, when the structure of the root system is known. A future challenge is to predict how the structure root systems responds to nutrient and water availability.
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Affiliation(s)
- Pieterjan De Bauw
- Katholieke Universiteit Leuven, Department of of Earth and Environmental Sciences, Leuven, Belgium
| | - Trung Hieu Mai
- Institute of Bio- and Geosciences: Agrosphere (IBG 3), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Andrea Schnepf
- Institute of Bio- and Geosciences: Agrosphere (IBG 3), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Roel Merckx
- Katholieke Universiteit Leuven, Department of of Earth and Environmental Sciences, Leuven, Belgium
| | - Erik Smolders
- Katholieke Universiteit Leuven, Department of of Earth and Environmental Sciences, Leuven, Belgium
| | - Jan Vanderborght
- Institute of Bio- and Geosciences: Agrosphere (IBG 3), Forschungszentrum Jülich GmbH, Jülich, Germany
- Katholieke Universiteit Leuven, Department of of Earth and Environmental Sciences, Leuven, Belgium
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Bagnall GC, Koonjoo N, Altobelli SA, Conradi MS, Fukushima E, Kuethe DO, Mullet JE, Neely H, Rooney WL, Stupic KF, Weers B, Zhu B, Rosen MS, Morgan CL. Low-field magnetic resonance imaging of roots in intact clayey and silty soils. GEODERMA 2020; 370:10.1016/j.geoderma.2020.114356. [PMID: 36452276 PMCID: PMC9706682 DOI: 10.1016/j.geoderma.2020.114356] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The development of a robust method to non-invasively visualize root morphology in natural soils has been hampered by the opaque, physical, and structural properties of soils. In this work we describe a novel technology, low field magnetic resonance imaging (LF-MRI), for imaging energy sorghum (Sorghum bicolor (L.) Moench) root morphology and architecture in intact soils. The use of magnetic fields much weaker than those used with traditional MRI experiments reduces the distortion due to magnetic material naturally present in agricultural soils. A laboratory based LF-MRI operating at 47 mT magnetic field strength was evaluated using two sets of soil cores: 1) soil/root cores of Weswood silt loam (Udifluventic Haplustept) and a Belk clay (Entic Hapluderts) from a conventionally tilled field, and 2) soil/root cores from rhizotrons filled with either a Houston Black (Udic Haplusterts) clay or a sandy loam purchased from a turf company. The maximum soil water nuclear magnetic resonance (NMR) relaxation time T2 (4 ms) and the typical root water relaxation time T2 (100 ms) are far enough apart to provide a unique contrast mechanism such that the soil water signal has decayed to the point of no longer being detectable during the data collection time period. 2-D MRI projection images were produced of roots with a diameter range of 1.5-2.0 mm using an image acquisition time of 15 min with a pixel resolution of 1.74 mm in four soil types. Additionally, we demonstrate the use of a data-driven machine learning reconstruction approach, Automated Transform by Manifold Approximation (AUTOMAP) to reconstruct raw data and improve the quality of the final images. The application of AUTOMAP showed a SNR (Signal to Noise Ratio) improvement of two fold on average. The use of low field MRI presented here demonstrates the possibility of applying low field MRI through intact soils to root phenotyping and agronomy to aid in understanding of root morphology and the spatial arrangement of roots in situ.
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Affiliation(s)
- G. Cody Bagnall
- Department of Biological and Agricultural Engineering, Texas A&M University, College Station, TX, USA
| | - Neha Koonjoo
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA 02129, USA
- Harvard Medical School, Boston, MA 02115, USA
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | | | - Mark S. Conradi
- ABQMR, Inc. 2301 Yale Blvd SE, Suite C2, Albuquerque, NM 87106, USA
| | - Eiichi Fukushima
- ABQMR, Inc. 2301 Yale Blvd SE, Suite C2, Albuquerque, NM 87106, USA
| | - Dean O. Kuethe
- ABQMR, Inc. 2301 Yale Blvd SE, Suite C2, Albuquerque, NM 87106, USA
| | - John E. Mullet
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Haly Neely
- Department of Soil and Crop Science, Texas A&M University, College Station, TX, USA
| | - William L. Rooney
- Department of Soil and Crop Science, Texas A&M University, College Station, TX, USA
| | - Karl F. Stupic
- National Institute of Standards and Technology, Applied Physics Division, 325 Broadway, Boulder, CO 80305, USA
| | - Brock Weers
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Bo Zhu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA 02129, USA
- Harvard Medical School, Boston, MA 02115, USA
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Matthew S. Rosen
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA 02129, USA
- Harvard Medical School, Boston, MA 02115, USA
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
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