Hyperspectral Image Target Detection Using Deep Ensembles for Robust Uncertainty Quantification.
Abstract not provided.
Sahay, Rajeev↗
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Simulating Reflected Light Exoplanet Spectra of the Promising Direct Imaging Target, υ Andromedae d, with a New, Fast Sampling Method Using the Planetary Spectrum Generator
Simulations of exoplanet albedo profiles are key to planning and interpreting future direct imaging observations. In this paper we demonstrate the use of the Planetary Spectrum Generator (PSG) to produce simulations of reflected light exoplanet spectra. We use PSG to examine multiple issues relevant to all models of directly imaged exoplanet spectra and to produce sample spectra of the bright, nearby exoplanet υ Andromedae d (υ And d), a potential direct imaging target for next-generation facilities. We introduce a new, fast, and accurate subsampling technique that enables calculations of disk-integrated spectra one order of magnitude faster than Chebyshev–Gauss sampling for moderate- to high-resolution sampling. Using this method and a first-principles-derived atmosphere for υ And d, we simulate phase-dependent spectra for a variety of different potential atmospheric configurations. The simulated spectra for υ And d include versions with different haze and cloud properties. Based on our combined analysis of this planet’s orbital parameters, phase- and illumination-appropriate model spectra, and realistic instrument noise parameters, we find that υ And d is a potentially favorable direct imaging and spectroscopy target for the Coronagraph Instrument (CGI) on the Nancy Grace Roman Space Telescope. When a noise model corresponding to the Roman CGI SPC spectroscopy mode is included, PSG predicts the time required to reach a signal-to-noise ratio of 10 of the simulated spectra in both the central wavelength bin of the Roman CGI SPC spectroscopy mode (R = 50 spectrum) and of the Band 1 HLC imaging mode is approximately 400 and less than 40 hr, respectively. We also discuss potential pathways to extricating information about the planet and its atmosphere with future observations and find that Roman observations may be able to bound the interior temperature of the planet.
74 ATOMIC AND MOLECULAR PHYSICS↗
“Off‐Label Use” of the Siderophore Enterobactin Enables Targeted Imaging of Cancer with Radioactive Ti (IV)
Abstract The development of inert, biocompatible chelation methods is required to harness the emerging positron emitting radionuclide 45 Ti for radiopharmaceutical applications. Herein, we evaluate the Ti (IV) ‐coordination chemistry of four catechol‐based, hexacoordinate chelators using synthetic, structural, computational, and radiochemical approaches. The siderophore enterobactin (Ent) and its synthetic mimic TREN‐CAM readily form mononuclear Ti (IV) species in aqueous solution at neutral pH. Radiolabeling studies reveal that Ent and TREN‐CAM form mononuclear complexes with the short‐lived, positron‐emitting radionuclide 45 Ti (IV) , and do not transchelate to plasma proteins in vitro and exhibit rapid renal clearance in naïve mice. These features guide efforts to target the 45 Ti isotope to prostate cancer tissue through the design, synthesis, and evaluation of Ent‐DUPA, a small molecule conjugate composed of a prostate specific membrane antigen (PSMA) targeting peptide and a monofunctionalized Ent scaffold. The [ 45 Ti][Ti(Ent‐DUPA)] 2− complex forms readily at room temperature. In a tumor xenograft model in mice, selective tumor tissue accumulation (8±5 %, n =5), and low off‐target uptake in other organs is observed. Overall, this work demonstrates targeted imaging with 45 Ti (IV) , provides a foundation for advancing the application of 45 Ti in nuclear medicine, and reveals that Ent can be repurposed as a 45 Ti‐complexing cargo for targeted nuclear imaging applications.
Koller, Angus J.↗
“Off‐Label Use” of the Siderophore Enterobactin Enables Targeted Imaging of Cancer with Radioactive Ti (IV)
The development of inert, biocompatible chelation methods is required to harness the emerging positron emitting radionuclide 45 Ti for radiopharmaceutical applications. Herein, we evaluate the Ti (IV) -coordination chemistry of four catechol-based, hexacoordinate chelators using synthetic, structural, computational, and radiochemical approaches. The siderophore enterobactin (Ent) and its synthetic mimic TREN-CAM readily form mononuclear Ti (IV) species in aqueous solution at neutral pH. Radiolabeling studies reveal that Ent and TREN-CAM form mononuclear complexes with the short-lived, positron-emitting radionuclide 45 Ti (IV) , and do not transchelate to plasma proteins in vitro and exhibit rapid renal clearance in naïve mice. These features guide efforts to target the 45 Ti isotope to prostate cancer tissue through the design, synthesis, and evaluation of Ent-DUPA, a small molecule conjugate composed of a prostate specific membrane antigen (PSMA) targeting peptide and a monofunctionalized Ent scaffold. Additionally, the [ 45 Ti][Ti(Ent-DUPA)] 2− complex forms readily at room temperature. In a tumor xenograft model in mice, selective tumor tissue accumulation (8±5 %, n=5), and low off-target uptake in other organs is observed. Overall, this work demonstrates targeted imaging with 45 Ti (IV) , provides a foundation for advancing the application of 45 Ti in nuclear medicine, and reveals that Ent can be repurposed as a 45 Ti-complexing cargo for targeted nuclear imaging applications.
62 RADIOLOGY AND NUCLEAR MEDICINE↗
Tumor-responsive dynamic nanoassemblies for targeted imaging, therapy and microenvironment manipulation
Not Available
Low, Liang Ee↗
Hyperspectral Image Target Detection Using Deep Ensembles for Robust Uncertainty Quantification.
Abstract not provided.
Sahay, Rajeev↗
Imaging systems and related methods including radar imaging with moving arrays or moving targets
Imaging systems, including radio frequency, microwave and millimeter-wave arrangements, and related methods are described. According to one aspect, an imaging system includes an antenna array, a position capture system configured to generate position information indicative of locations of one of the antenna array and the target at the first and second moments in time, and wherein the one of the antenna array and the target move between the first and second moments in time, a transceiver configured to control the antenna array to emit electromagnetic energy towards the target and to generate an output that is indicative of the received electromagnetic energy, a data acquisition system configured to generate radar data, processing circuitry configured to process the position information and the radar data to generate image data regarding the target, and an interface configured to use the image data to generate visual images regarding the target.
Sheen, David M.↗
Imaging systems and related methods including radar imaging with moving arrays or moving targets
Imaging systems, including radio frequency, microwave and millimeter-wave arrangements, and related methods are described. According to one aspect, an imaging system includes an antenna array, a position capture system configured to generate position information indicative of locations of one of the antenna array and the target at the first and second moments in time, and wherein the one of the antenna array and the target move between the first and second moments in time, a transceiver configured to control the antenna array to emit electromagnetic energy towards the target and to generate an output that is indicative of the received electromagnetic energy, a data acquisition system configured to generate radar data, processing circuitry configured to process the position information and the radar data to generate image data regarding the target, and an interface configured to use the image data to generate visual images regarding the target.
Sheen, David M.↗
Universal image representation based on a multimodal graph
A system for classifying a target image with segments having attributes is provided. The system generates a graph for the target image that includes vertices representing segments of the image and edges representing relationships between the connected vertices. For each vertex, the system generates a subgraph that includes the vertex as a home vertex and neighboring vertices representing segments of the target image within a neighborhood of the segment represented by the home vertex. The system applies an autoencoder to each subgraph to generate latent variables to represent the subgraph. The system applies a machine learning algorithm to a feature vector comprising a universal image representation of the target image that is derived from the generated latent variables of the subgraphs to generate a classification for the target image.
Bremer, Peer-Timo↗
Universal image representation based on a multimodal graph
A system for classifying a target image with segments having attributes is provided. The system generates a graph for the target image that includes vertices representing segments of the image and edges representing relationships between the connected vertices. For each vertex, the system generates a subgraph that includes the vertex as a home vertex and neighboring vertices representing segments of the target image within a neighborhood of the segment represented by the home vertex. The system applies an autoencoder to each subgraph to generate latent variables to represent the subgraph. The system applies a machine learning algorithm to a feature vector comprising a universal image representation of the target image that is derived from the generated latent variables of the subgraphs to generate a classification for the target image.
Bremer, Peer-Timo↗
Compositions for therapeutics, targeted PET imaging and methods of their use
Described herein is a chelator for radiolabels (e.g., 89Zr) for targeted PET imaging that is an alternative to DFO. In certain embodiments, the chelator for 89Zr is the ligand, 3,4,3-(LI-1,2-HOPO) (“HOPO”), which exhibits equal or superior stability compared to DFO in chemical and biological assays across a period of several days in vivo. As shown in FIG. 1, the HOPO is an octadentate chelator that stabilizes chelation of radiolabels (e.g., 89Zr). A bifunctional ligand comprising p-SCN-Bn-HOPO is shown in FIG. 4 and FIG. 5. Such a bifunctional ligand can eliminate (e.g., 89Zr) loss from the chelate in vivo and reduce uptake in bone and non-target tissue. Therefore, the bifunctional HOPO ligand can facilitate safer and improved PET imaging with radiolabeled antibodies.
Lewis, Jason S.↗
Novel theranostic agent for PET imaging and targeted radiopharmaceutical therapy of tumour-infiltrating immune cells in glioma
Background: Malignant gliomas are deadly tumours with few therapeutic options. Although immunotherapy may be a promising therapeutic strategy for treating gliomas, a significant barrier is the CD11b + tumour-associated myeloid cells (TAMCs), a heterogeneous glioma infiltrate comprising up to 40% of a glioma's cellular mass that inhibits anti-tumour T-cell function and promotes tumour progression. A theranostic approach uses a single molecule for targeted radiopharmaceutical therapy (TRT) and diagnostic imaging; however, there are few reports of theranostics targeting the tumour microenvironment. Methods: Utilizing a newly developed bifunctional chelator, Lumi804, an anti-CD11b antibody (αCD11b) was readily labelled with either Zr-89 or Lu-177, yielding functional radiolabelled conjugates for PET, SPECT, and TRT. Findings: 89 Zr/ 177 Lu-labeled Lumi804-αCD11b enabled non-invasive imaging of TAMCs in murine gliomas. Additionally, 177 Lu-Lumi804-αCD11b treatment reduced TAMC populations in the spleen and tumour and improved the efficacy of checkpoint immunotherapy. Interpretation: 89 Zr- and 177 Lu-labeled Lumi804-αCD11b may be a promising theranostic pair for monitoring and reducing TAMCs in gliomas to improve immunotherapy responses.
60 APPLIED LIFE SCIENCES↗
Automated Registration of Vector Data to Overhead Imagery
The availability of open source, remote sensing-derived vector data has increased exponentially in recent years. Unfortunately, these vector data are rarely made available with the corresponding source images from which objects were extracted. As such, these derived datasets are commonly used in combination with target images which differ from the source. Satellite viewing geometry can cause objects, extracted from a source image, to appear shifted when overlaid with a target image. Whether for purely cartographic purposes, reusability of preexisting training labels, or any spatial analysis where spatial correspondence between vector and image are required, the following paragraphs outline a method to address this challenge through the automated registration of vector data to overhead imagery, including existing literature regarding this challenge, followed by a case study of Sioux Falls, South Dakota.
McKee, Jacob↗
Fluorine-18 incorporation and radiometal coordination in macropa ligands for PET imaging and targeted alpha therapy
The development of theranostic agents for radiopharmaceuticals based on therapeutic alpha emitters marks an important clinical need.
Kanagasundaram, Thines↗
Deep learning-based spatio-temporal fusion for high-fidelity ultra-high-speed X-ray radiography
Full-field ultra-high-speed (UHS) X-ray imaging experiments have been well established to characterize various processes and phenomena. However, the potential of UHS experiments through the joint acquisition of X-ray videos with distinct configurations has not been fully exploited. In this paper, we investigate the use of a deep learning-based spatio-temporal fusion (STF) framework to fuse two complementary sequences of X-ray images and reconstruct the target image sequence with high spatial resolution, high frame rate and high fidelity. We applied a transfer learning strategy to train the model and compared the peak signal-to-noise ratio (PSNR), average absolute difference (AAD) and structural similarity (SSIM) of the proposed framework on two independent X-ray data sets with those obtained from a baseline deep learning model, a Bayesian fusion framework and the bicubic interpolation method. The proposed framework outperformed the other methods with various configurations of the input frame separations and image noise levels. With three subsequent images from the low-resolution (LR) sequence of a four times lower spatial resolution and another two images from the high-resolution (HR) sequence of a 20 times lower frame rate, the proposed approach achieved average PSNRs of 37.57 dB and 35.15 dB, respectively. When coupled with the appropriate combination of high-speed cameras, the proposed approach will enhance the performance and therefore the scientific value of UHS X-ray imaging experiments.
deep learning↗
The design of a line velocity interferometer for any reflector for inertial confinement experiments on the Z-machine
A line VISAR (Velocity Interferometer System for Any Reflector) has been designed and commissioned at the Sandia National Laboratory’s Z-machine. The instrument consists of an F/2 collection system, beam transport, and an interferometer table that contains two Mach–Zehnder type interferometers and an eight channel Gated Optical Imaging (GOI) system. The VISAR probe laser operates at the 532 nm wavelength, and the GOI bandpass is 540–600 nm. The output of each interferometer is passed to an optical streak camera with four selectable sweep speeds. The system is designed with three interchangeable optics modules to select a full field of view of 1 mm, 2 mm, or 4 mm. The optical beam transport system connects the target image plane to the interferometers and the gated optical imagers. The target is integrated into a sacrificial final optics assembly that is integral to the transport beamline.
Datte, P.↗
PET Imaging of the Neurotensin Targeting Peptide NOTA-NT-20.3 Using Cobalt-55, Copper-64 and Gallium-68
Introduction: Neurotensin receptor 1 (NTSR1) is an emerging target for imaging and therapy of many types of cancer. Nuclear imaging of NTSR1 allows for noninvasive assessment of the receptor levels of NTSR1 on the primary tumor, as well as potential metastases. This work focuses on a the neurotensin peptide analogue NT-20.3 conjugated to the chelator NOTA for radiolabeling for use in noninvasive positron emission tomography (PET). NOTA-NT-20.3 was radiolabeled with gallium-68, copper-64, and cobalt-55 to determine the effect that modification of the radiometal has on imaging and potential therapeutic properties of NOTA-NT-20.3. Methods: In vitro assays investigating cell uptake and subcellular localization of the radiolabeled peptides were performed using human colorectal adenocarcinoma HT29 cells. In vivo PET/CT imaging was used to determine the distribution and clearance of the peptide in mice bearing NTSR1 expressing HT29 tumors. Results: Cell uptake studies showed that the highest uptake was obtained with [ 55 Co] Co-NOTA-NT-20.3 (18.70 ± 1.30%ID/mg), followed by [ 64 Cu] Cu-NOTA-NT-20.3 (15.46 ± 0.91%ID/mg), and lastly [ 68 Ga] Ga-NOTA-NT-20.3 (10.94 ± 0.46%ID/mg) (p < 0.001). Subcellular distribution was similar across the three constructs, with the membranous fraction containing the highest amount of radioactivity. In vivo PET/CT imaging of the three constructs revealed similar distribution and tumor uptake at the 1 h imaging timepoint. Tumor uptake was receptor-specific and blockable by co-injection of non-radiolabeled NOTA-NT-20.3. SUV ratios of tumor to heart at the 24 h imaging timepoint show that [ 55 Co] Co-NOTA-NT-20.3 (20.28 ± 3.04) outperformed [ 64 Cu] Cu-NOTA-NT-20.3 (6.52 ± 1.97). In conclusion, our studies show that enhanced cell uptake and increasing tumor to blood ratios over time displayed the superiority of [ 55 Co] Co-NOTA-NT-20.3 over [ 68 Ga] Ga-NOTA-NT-20.3 and [ 64 Cu] Cu-NOTA-NT-20.3 for the targeting of NTSR1.
60 APPLIED LIFE SCIENCES↗
Nano-laminography with a transmission X-ray microscope
Nano-laminography combines the penetrating power of hard X-rays with a tilted rotational geometry to deliver high-resolution, three-dimensional images of laterally extended, flat specimens that are otherwise incompatible with, or difficult to image using, conventional nano-tomography. In this work, we demonstrate a full-field, X-ray nano-laminography system implemented with the transmission X-ray microscope at beamline 32-ID of the upgraded Advanced Photon Source at Argonne National Laboratory, USA. By rotating the sample around an axis inclined by 20° to the incident beam, the technique minimizes the long optical path lengths that would otherwise generate excessive artifacts when planar samples are imaged edge-on. The efficiency of the technique is demonstrated with 50 nm spatial resolution and minute-scale temporal resolution 3D imaging of a planar integrated circuit sample and targeted imaging of an individual particle within a powder sample, where mounting procedures are typically challenging in regular nano-tomography. The sample mounting strategy, data acquisition, and reconstruction method will also be discussed.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗