Position sensitive radiation detector

An apparatus and method are disclosed for detecting and locating the origin of a gamma ray in a medical diagnostic imaging system. At least one primary fiber, which is a scintillating optical fiber, is positioned to receive radiation from a gamma ray source. At least one secondary fiber intersects the primary fiber at a non-zero angle. Both fibers have a core surrounded by a cladding, with the claddings of the two fibers in optical contact at an intersection point. Both the primary and secondary fibers are provided with means for detecting light propagated in the fibers. The interaction of radiation such as a gamma ray with the primary fiber will result in the propagation of light in both the primary and secondary fibers, thereby permitting the determination of the site of impact of the gamma ray in the detector, and possibly also enabling the determination of the path of incidence of the gamma ray.Board of Regents, University of Texas Syste

Method and apparatus for analyzing material properties using ultrasound

Apparatus is disclosed for investigating the mechanical properties of a solid material such as bone, including means for positioning the apparatus in proximity to a surface of the material, at least one emitting ultrasound transducer, at least one receiving ultrasound transducer positioned to received ultrasound waves that have been emitted and have contacted the surface of the material, means for varying the angle of incidence of the emitted ultrasound wave towards the material, means for determining the alignment of the surface of the material with respect to the emitting and receiving ultrasound transdsucers, and signal analyzer means coupled to the receiving transducer for determining at least one characteristic of the received ultrasound wave which is indicative of a mechanical property of the material. A method is also disclosed of using such apparatus. The present invention permits the quick and efficient evaluation of treatment for osteoporosis, and whether that treatment has in fact reduced the tendency of a patient's bones to fracture.Board of Regents, University of Texas Syste

Nanoparticulate Radiolabelled Quinolines Detect Amyloid Plaques in Mouse Models of Alzheimer's Disease

Detecting aggregated amyloid peptides (Aβ plaques) presents targets for developing biomarkers of Alzheimer's disease (AD). Polymeric n-butyl-2-cyanoacrylate (PBCA) nanoparticles (NPs) were encapsulated with radiolabelled amyloid affinity 125I-clioquinol (CQ, 5-chloro-7-iodo-8-hydroxyquinoline) as in vivo probes. 125I-CQ-PBCA NPs crossed the BBB (2.3 ± 0.9 ID/g) (P < .05) in the WT mouse (N = 210), compared to 125I-CQ (1.0 ± 0.4 ID/g). 125I-CQ-PBCA NP brain uptake increased in AD transgenic mice (APP/PS1) versus WT (N = 38; 2.54 × 105 ± 5.31 × 104 DLU/mm2; versus 1.98 × 105 ± 2.22 × 104 DLU/mm2) and in APP/PS1/Tau. Brain increases were in mice intracranially injected with aggregated Aβ42 peptide (N = 17; 7.19 × 105 ± 1.25 × 105 DLU/mm2), versus WT (6.07 × 105 ± 7.47 × 104 DLU/mm2). Storage phosphor imaging and histopathological staining of the plaques, Fe2+ and Cu2+, validated results. 125I-CQ-PBCA NPs have specificity for Aβ in vitro and in vivo and are promising as in vivo SPECT (123I), or PET (124I) amyloid imaging agents

Altimetry for the future: Building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the ‘‘Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

Altimetry for the future: building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the “Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

19F labelled dextrans and antibodies as NMR imaging and spectroscopy agents

.sup.19 F labelled compounds are disclosed which are useful in methods of NMR imaging and spectroscopy. The compounds comprise a .sup.19 F-containing sensor moiety, and a transport polymer or substrate, and can optionally also comprise a spacer moiety to separate the sensor moiety and the transport polymer.Board of Regents, University of Texas Syste

Validating Bioluminescence Imaging as a High-Throughput, Quantitative Modality for Assessing Tumor Burden

Bioluminescence imaging (BLI) is a highly sensitive tool for visualizing tumors, neoplastic development, metastatic spread, and response to therapy. Although BLI has engendered much excitement due to its apparent simplicity and ease of implementation, few rigorous studies have been presented to validate the measurements. Here, we characterize the nature of bioluminescence output from mice bearing subcutaneous luciferase-expressing tumors over a 4-week period. Following intraperitoneal or direct intratumoral administration of luciferin substrate, there was a highly dynamic kinetic profile of light emission. Although bioluminescence was subject to variability, strong correlations ( r > .8, p < .001) between caliper measured tumor volumes and peak light signal, area under light signal curve and light emission at specific time points were determined. Moreover, the profile of tumor growth, as monitored with bioluminescence, closely resembled that for caliper measurements. The study shows that despite the dynamic and variable nature of bioluminescence, where appropriate experimental precautions are taken, single time point BLI may be useful for noninvasive, high-throughput, quantitative assessment of tumor burden

A Multi-Camera System for Bioluminescence Tomography in Preclinical Oncology Research

Bioluminescent imaging (BLI) of cells expressing luciferase is a valuable noninvasive technique for investigating molecular events and tumor dynamics in the living animal. Current usage is often limited to planar imaging, but tomographic imaging can enhance the usefulness of this technique in quantitative biomedical studies by allowing accurate determination of tumor size and attribution of the emitted light to a specific organ or tissue. Bioluminescence tomography based on a single camera with source rotation or mirrors to provide additional views has previously been reported. We report here in vivo studies using a novel approach with multiple rotating cameras that, when combined with image reconstruction software, provides the desired representation of point source metastases and other small lesions. Comparison with MRI validated the ability to detect lung tumor colonization in mouse lung