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Sample records for radioisotope intravascular radiation

  1. Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System

    SciTech Connect

    Eigler, N.; Whiting, J.; Chernomorsky, A.; Jackson, J.; Knapp, F.F., Jr.; Litvack, F.

    1998-01-16

    RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Champion{trademark} over-the-wire, and TNT{trademark} rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors.

  2. Emitted radiation characteristics of plutonium dioxide radioisotope thermoelectric generators

    NASA Technical Reports Server (NTRS)

    Gingo, P. J.; Steyn, J. J.

    1971-01-01

    The nuclear and emitted radiation characteristics of the radioisotope elements and impurities in commercial grade plutonium dioxide are presented in detail. The development of the methods of analysis are presented. Radioisotope thermoelectric generators (RTG) of 1575, 3468 and 5679 thermal watts are characterized with respect to neutron and gamma photon source strength as well as spatial and number flux distribution. The results are presented as a function of detector position and light element contamination concentration for fuel age ranging from 'fresh' to 18 years. The data may be used to obtain results for given O-18 and Pu-236 concentrations. The neutron and gamma photon flux and dose calculations compare favorably with reported experimental values for SNAP-27.

  3. Radioisotopic energy conversion system (RECS): A new radioisotopic power cell, based on nuclear, atomic, and radiation transport principles

    NASA Astrophysics Data System (ADS)

    Steinfelds, Eric Victor

    The topic of this thesis is the development of the Radioisotope Energy Conversion System (RECS) in a project which is utilizing analytical computational assisted design and some experimental Research in the investigation of fluorescers and effective transducers with the appropriate energy range choice for the conversion of energy. It is desirable to increase the efficiency in electrical power from the raw kinetic power available from the radioactive material within radioisotope power generators. A major step in this direction is the development and use of Radioisotope Energy Conversion Systems to supplement and ideally replace Radioactive Thermal Generators (RTG). It is possible to achieve electrical conversion efficiencies exceeding 25% for RECS power devices compared to only 9 percent efficiency for RTG's. The theoretical basis with existent materials for the potential achievability of efficiencies above 25% is documented within this thesis. The fundamental RECS consists of a radioisotope radiative source (C1), a mediating fluorescent gas (C2) which readily absorbs energy from the beta particles (or alpha's) and subsequently emits blue or UV photons, photovoltaic cells (C3) to convert the blue and UV photons into electrical energy [2], and electrical circuitry (C4). Solid State inspired component (C3), due to its theoretical (and attainable) high efficiency, is a large step ahead of the RTG design concept. The radioisotope flux source produces the beta(-) particles or alpha particles. Geometrically, presently, we prefer to have the ambient fluorescent gas surround the radioisotope flux source. Our fluorescer shall be a gas such as Krypton. Our specifically wide band-gap photovoltaic cells shall have gap energies which are slightly less than that of UV photons produced by the fluorescing gas. Diamond and Aluminum Nitride sample materials are good potential choices for photovoltaic cells, as is explained here in. Out of the material examples discussed, the highest

  4. Delivery of therapeutic radioisotopes using nanoparticle platforms: potential benefit in systemic radiation therapy

    PubMed Central

    Zhang, Longjiang; Chen, Hongwei; Wang, Liya; Liu, Tian; Yeh, Julie; Lu, Guangming; Yang, Lily; Mao, Hui

    2010-01-01

    Radiation therapy is an effective cancer treatment option in conjunction with chemotherapy and surgery. Emerging individualized internal and systemic radiation treatment promises significant improvement in efficacy and reduction of normal tissue damage; however, it requires cancer cell targeting platforms for efficient delivery of radiation sources. With recent advances in nanoscience and nanotechnology, there is great interest in developing nanomaterials as multifunctional carriers to deliver therapeutic radioisotopes for tumor targeted radiation therapy, to monitor their delivery and tumor response to the treatment. This paper provides an overview on developing nanoparticles for carrying and delivering therapeutic radioisotopes for systemic radiation treatment. Topics discussed in the review include: selecting nanoparticles and radiotherapy isotopes, strategies for targeting nanoparticles to cancers, together with challenges and potential solutions for the in vivo delivery of nanoparticles. Some examples of using nanoparticle platforms for the delivery of therapeutic radioisotopes in preclinical studies of cancer treatment are also presented. PMID:24198480

  5. Intravascular Ultrasound Catheter to Enhance Microbubble-Based Drug Delivery via Acoustic Radiation Force

    PubMed Central

    Kilroy, Joseph P.; Klibanov, Alexander L.; Wamhoff, Brian R.; Hossack, John A.

    2015-01-01

    Previous research has demonstrated that acoustic radiation force enhances intravascular microbubble adhesion to blood vessels in the presence of flow for molecular-targeted ultrasound imaging and drug delivery. A prototype acoustic radiation force intravascular ultrasound (ARFIVUS) catheter was designed and fabricated to displace a microbubble contrast agent in flow representative of conditions encountered in the human carotid artery. The prototype ARFIVUS transducer was designed to match the resonance frequency of 1.4- to 2.6-μm-diameter microbubbles modeled by an experimentally verified 1-D microbubble acoustic radiation force translation model. The transducer element was an elongated Navy Type I (hard) lead zirconate titanate (PZT) ceramic designed to operate at 3 MHz. Fabricated devices operated with center frequencies of 3.3 and 3.6 MHz with −6-dB fractional bandwidths of 55% and 50%, respectively. Microbubble translation velocities as high as 0.86 m/s were measured using a high-speed streak camera when insonating with the ARFIVUS transducer. Finally, the prototype was used to displace microbubbles in a flow phantom while imaging with a commercial 45-MHz imaging IVUS transducer. A sustained increase of 31 dB in average video intensity was measured following insonation with the ARFIVUS, indicating microbubble accumulation resulting from the application of acoustic radiation force. PMID:23143566

  6. Personal reflections on the highlights and changes in radiation and radioisotope measurement applications

    NASA Astrophysics Data System (ADS)

    Gardner, Robin P.; Lee, Kyoung O.

    2015-11-01

    This paper describes the recent changes that the authors have perceived in the use of radiation and radioisotope measurement applications. The first change is that due to the increased use of Monte Carlo simulation which has occurred from a normal evolutionary process. This is due in large part to the increased accuracy that is being obtained by the use of detector response functions (DRFs) and the simultaneous increased computational efficiency that has become available with these DRFs, the availability of a greatly improved weight windows variance reduction method, and the availability of inexpensive computer clusters. This first change is a happy one. The other change that is occurring is in response to recent terrorist activities. That change is the replacement or major change in the use of long-lived radioisotopes in radioisotope measurement and other radioisotope source applications. In general this can be done by improving the security of these radioisotope sources or by replacing them altogether by using machine sources of radiation. In either case one would like to preclude altogether or at least minimize the possibility of terrorists being able to obtain radioisotopes and use them for clandestine purposes.

  7. Deposition of (90)YPO(4) and (144)CePO(4) radioisotopes on polymer surfaces for radiation delivery devices.

    PubMed

    Qu, Xin; Weinberger, Judah

    2002-01-01

    Intravascular irradiation with beta emitters inhibits restenosis in arteries after balloon angioplasty or stent implantation. Yttrium-90 ((90)Y, T(1/2)=64 h) and cerium-144 ((144)Ce, T(1/2)=286 d) emit beta particles (E(max)=2.28--3.50 MeV) having an ideal energy range for brachytherapy delivery system. In this article, a previously reported method for depositing (32)P on poly(ethylene terephtalate) (PET) surfaces is generalized and modifications that allow deposition of other beta-emitting radioisotopes, such as (90)Y and (144)Ce, are demonstrated. PET films were first coated with chitosan hydrogel and then adsorbed different amounts of phosphoric acid (PA) in aqueous solutions. Yttrium was deposited onto the surface as YPO(4) after the films were immersed in YCl(3) solutions. 1 muCi (90)YCl(3) (2 x 10(-9) g) was used in each sample as a tracer for measuring the deposition efficiency, which is defined as the percentage of YCl(3) deposited on the surface compared to the amount of YCl(3) in solutions before the deposition. In order to improve the safety of brachytherapy treatments, polyurethanes were used to seal the deposited radioisotopes on the surface to minimize the leakage of the isotopes into the patients. The generality of this method presented here for a wide variety of particular radioisotopic components allows design of a broad range of versatile radioisotope sources. PMID:11870641

  8. Evidence for Radiation-Induced Disseminated Intravascular Coagulation as a Major Cause of Radiation-Induced Death in Ferrets

    SciTech Connect

    Krigsfeld, Gabriel S.; Savage, Alexandria R.; Billings, Paul C.; Lin, Liyong; Kennedy, Ann R.

    2014-03-15

    Purpose: The studies reported here were performed as part of a program in space radiation biology in which proton radiation like that present in solar particle events, as well as conventional gamma radiation, were being evaluated in terms of the ability to affect hemostasis. Methods and Materials: Ferrets were exposed to 0 to 2 Gy of whole-body proton or gamma radiation and monitored for 30 days. Blood was analyzed for blood cell counts, platelet clumping, thromboelastometry, and fibrin clot formation. Results: The lethal dose of radiation to 50% of the population (LD{sub 50}) of the ferrets was established at ∼1.5 Gy, with 100% mortality at 2 Gy. Hypocoagulability was present as early as day 7 postirradiation, with animals unable to generate a stable clot and exhibiting signs of platelet aggregation, thrombocytopenia, and fibrin clots in blood vessels of organs. Platelet counts were at normal levels during the early time points postirradiation when coagulopathies were present and becoming progressively more severe; platelet counts were greatly reduced at the time of the white blood cell nadir of 13 days. Conclusions: Data presented here provide evidence that death at the LD{sub 50} in ferrets is most likely due to disseminated intravascular coagulation (DIC). These data question the current hypothesis that death at relatively low doses of radiation is due solely to the cell-killing effects of hematopoietic cells. The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation-induced death at relatively low doses in large mammals.

  9. Evidence for Radiation-Induced Disseminated Intravascular Coagulation as a Major Cause of Radiation-Induced Death in Ferrets

    PubMed Central

    Krigsfeld, Gabriel S.; Savage, Alexandria R.; Billings, Paul C.; Lin, Liyong; Kennedy, Ann R.

    2014-01-01

    Purpose/Objectives(s) The studies reported here were performed as part of a program in space radiation biology in which proton radiation like that present in solar particle events (SPEs), as well as conventional gamma radiation, were being evaluated in terms of the ability to affect hemostasis. Methods and Materials Ferrets were exposed to 0 – 2 Gray (Gy) of whole body proton or gamma radiation and monitored for 30 days. Blood was analyzed for blood cell counts, platelet clumping, thromboelastometry, and fibrin clot formation. Results The lethal dose of radiation to 50% of the population, known as the LD50, of ferrets was established at ~ 1.5 Gy, with 100% mortality at 2 Gy. Hypocoagulability was present as early as day 7 post-irradiation, with animals unable to generate a stable clot and exhibiting signs of platelet aggregation, thrombocytopenia, and fibrin clots in blood vessels of organs. Platelet counts were at normal levels during the early times post-irradiation when coagulopathies were present and progressively becoming more severe; platelet counts were greatly reduced at the time of the white blood cell nadir of 13 days. Conclusions The data presented here provide evidence that death at the LD50 in ferrets is most likely due to disseminated intravascular coagulation (DIC). These data question the current hypothesis that death at relatively low doses of radiation is solely due to the cell killing effects of hematopoietic cells. The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation induced death at relatively low doses in large mammals. PMID:24495588

  10. Evidence of disseminated intravascular coagulation in a porcine model following radiation exposure

    NASA Astrophysics Data System (ADS)

    Krigsfeld, G. S.; Shah, J. B.; Sanzari, J. K.; Lin, L.; Kennedy, A. R.

    2014-10-01

    Recent evidence has suggested that disseminated intravascular coagulation (DIC) plays an integral role in death at the LD50 dose of either gamma or solar particle event (SPE)-like proton radiation in ferrets. In these studies, Yucatan minipigs were evaluated to determine whether they were susceptible to the development of radiation induced DIC. Yucatan minipigs were exposed to a dose of 2.5 Gray (Gy) with X-rays and monitored over the course of 30 days. Evidence of DIC was evaluated by way of thromboelastometry parameters, platelet counts, fibrinogen concentration, and the d-dimer assay. Pigs exposed to X-rays developed signs of DIC within 2 days' post-irradiation. The development of DIC was exacerbated over the course of the studies, and one of the pigs died at day 14 and another had to be euthanized on day 16 post-irradiation. For both of these pigs, DIC was evident at the time of death. The following observations were indicated or were suggestive of DIC: whole blood clotting was impaired (as evidenced by thromboelastometry alterations), there were decreased platelet counts, elevated d-dimer concentrations in the blood, and/or hemorrhaging and the presence of fibrin in tissues observed during post-mortem examination. The extrapolation of data from these studies, in combination with other published data, have led to the hypothesis that there could be a correlation between the propensity to develop DIC, as indicated by hemorrhaging at death at relatively low doses of radiation, and the LD50 for a particular species. Our data suggest that the development of DIC may contribute to death at the LD50 dose in large mammals.

  11. Evidence of Disseminated Intravascular Coagulation in a Porcine Model Following Radiation Exposure

    PubMed Central

    Krigsfeld, G.S.; Shah, J.B.; Sanzari, J.K.; Lin, L.; Kennedy, A.R.

    2014-01-01

    Recent evidence has suggested that disseminated intravascular coagulation (DIC) plays an integral role in death at the LD50 dose of either gamma or solar particle event (SPE)-like proton radiation in ferrets. In these studies, Yucatan minipigs were evaluated to determine whether they were susceptible to the development of radiation induced DIC. Yucatan minipigs were exposed to a dose of 2.5 Gray (Gy) with x-rays and monitored over the course of 30 days. Evidence of DIC was evaluated by way of thromboelastometry parameters, platelet counts, fibrinogen concentration, and the d-dimer assay. Pigs exposed to x-rays developed signs of DIC within 2 days post-irradiation. The development of DIC was exacerbated over the course of the studies, and one of the pigs died at day 14 and another had to be euthanized on day 16 post-irradiation. For both of these pigs, DIC was evident at the time of death. The following observations were indicated or were suggestive of DIC: whole blood clotting was impaired (as evidenced by thromboelastometry alterations), there were decreased platelet counts, elevated d-dimer concentrations in the blood, and/or hemorrhaging and the presence of fibrin in tissues observed during post-mortem examination. The extrapolation of data from these studies, in combination with other published data, have led to the hypothesis that there could be a correlation between the propensity to develop DIC, as indicated by hemorrhaging at death at relatively low doses of radiation, and the LD50 for a particular species. Our data suggest that the development of DIC may contribute to death at the LD50 dose in large mammals. PMID:25197627

  12. Organic Materials Ionizing Radiation Susceptibility for the Outer Planet/Solar Probe Radioisotope Power Source

    NASA Technical Reports Server (NTRS)

    Golliher, Eric L.; Pepper, Stephen V.

    2001-01-01

    The Department of Energy is considering the current Stirling Technology Corporation 55 We Stirling Technology Demonstration Convertor as a baseline option for an advanced radioisotope power source for the Outer Planets/Solar Probe project of Jet Propulsion Laboratory and other missions. However, since the Technology Demonstration Convertor contains organic materials chosen without any special consideration of flight readiness, and without any consideration of the extremely high radiation environment of Europa, a preliminary investigation was performed to address the radiation susceptibility of the current organic materials used in the Technology Demonstration Convertor. This report documents the results of the investigation. The results of the investigation show that candidate replacement materials have been identified to be acceptable in the harsh Europa radiation environment.

  13. Sodium VCHP with Carbon-Carbon Radiator for Radioisotope Stirling Systems

    NASA Astrophysics Data System (ADS)

    Tarau, Calin; Anderson, William G.; Miller, William O.; Ramirez, Rogelio

    2010-01-01

    In a Stirling radioisotope system, heat must continually be removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling converter normally provides this cooling. If the Stirling convertor stops in the current system the insulation is designed to spoil, preventing damage to the GPHS at the cost of an earlier termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to allow multiple stops and restarts of the Stirling convertor. A sodium VCHP with a Haynes 230 envelope was designed and fabricated for the Advanced Stirling Radioisotope Generator (ASRG), with a baseline 850° C heater head temperature. When the Stirling convertor is stopped, the heat from the GPHS is rejected to the Cold Side Adapter Flange using a low-mass, carbon-carbon radiator. The VCHP is designed to activate with a AT of 30° C. The 880° C temperature when the Stirling convertor is stopped is high enough to avoid risking standard ASRG operation, but low enough to save most of the heater head life. The VCHP has low mass and low thermal losses for normal operation. The design has been modified from an earlier, stainless steel prototype with a nickel radiator. In addition to replacing the nickel radiator with a low mass carbon-carbon radiator, the radiator location has been moved from the ASRG case to the cold side adapter flange. This flange already removes two-thirds of the heat during normal operation, so it is optimized to transfer heat to the case. The VCHP was successfully tested with a turn-on ΔT of 30° C in three orientations: horizontal, gravity-aided, and against gravity.

  14. Radiation Environments and Exposure Considerations for the Multi-Mission Radioisotope Thermoelectric Generator

    NASA Astrophysics Data System (ADS)

    Kelly, William M.; Low, Nora M.; Zillmer, Andrew; Johnson, Gregory A.; Normand, Eugene

    2006-01-01

    The Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) is the next generation (RTG) being developed by DOE to provide reliable, long-life electric power for NASA's planetary exploration programs. The MMRTG is being developed by Pratt & Whitney Rocketdyne and Teledyne Energy Systems Incorporated (TESI) for use on currently planned and projected flyby, orbital and planet landing missions. This is a significant departure from the design philosophy of the past which was to match specific mission requirements to RTG design capabilities. Undefined mission requirements provide a challenge to system designers by forcing them to put a design envelope around ``all possible missions''. These multi-mission requirements include internal and external radiation sources. Internal sources include the particles ejected by decaying Pu-238 and its daughters plus particles resulting from the interaction of these particles with other MMRTG materials. External sources include the full spectrum of charged particle radiation surrounding planets with magnetic fields and the surfaces of extraterrestrial objects not shielded by magnetic fields. The paper presents the results of investigations into the environments outlined above and the impact of radiation exposure on potential materials to be used on MMRTG and ground support personnel. Mission requirements were also reviewed to evaluate total integrated dose and to project potential shielding requirements for materials. Much of the information on mission shielding requirements was provided by NASA's Jet Propulsion Laboratory. The primary result is an ionizing radiation design curve which indicates the limits to which a particular mission can take the MMRTG in terms of ionizing radiation exposure. Estimates of personnel radiation exposure during ground handling are also provided.

  15. Radiation Environments and Exposure Considerations for the Multi-Mission Radioisotope Thermoelectric Generator

    SciTech Connect

    Kelly, William M.; Low, Nora M.; Zillmer, Andrew; Johnson, Gregory A.; Normand, Eugene

    2006-01-20

    The Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) is the next generation (RTG) being developed by DOE to provide reliable, long-life electric power for NASA's planetary exploration programs. The MMRTG is being developed by Pratt and Whitney Rocketdyne and Teledyne Energy Systems Incorporated (TESI) for use on currently planned and projected flyby, orbital and planet landing missions. This is a significant departure from the design philosophy of the past which was to match specific mission requirements to RTG design capabilities. Undefined mission requirements provide a challenge to system designers by forcing them to put a design envelope around 'all possible missions'. These multi-mission requirements include internal and external radiation sources. Internal sources include the particles ejected by decaying Pu-238 and its daughters plus particles resulting from the interaction of these particles with other MMRTG materials. External sources include the full spectrum of charged particle radiation surrounding planets with magnetic fields and the surfaces of extraterrestrial objects not shielded by magnetic fields. The paper presents the results of investigations into the environments outlined above and the impact of radiation exposure on potential materials to be used on MMRTG and ground support personnel. Mission requirements were also reviewed to evaluate total integrated dose and to project potential shielding requirements for materials. Much of the information on mission shielding requirements was provided by NASA's Jet Propulsion Laboratory. The primary result is an ionizing radiation design curve which indicates the limits to which a particular mission can take the MMRTG in terms of ionizing radiation exposure. Estimates of personnel radiation exposure during ground handling are also provided.

  16. Radioisotopes: Today's Applications.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC. Nuclear Energy Office.

    Radioisotopes are useful because of their three unique characteristics: (1) radiation emission; (2) predictable radioactive lives; and (3) the same chemical properties as the nonradioactive atoms of that element. Researchers are able to "order" a radioisotope with the right radiation, half-life, and chemical property to perform a given task with…

  17. Intravascular ultrasound

    MedlinePlus

    IVUS; Ultrasound - coronary artery; Endovascular ultrasound; Intravascular echocardiography ... A tiny ultrasound wand is attached to the top of a thin tube. This tube is called a catheter. The catheter ...

  18. Intravascular OCT

    NASA Astrophysics Data System (ADS)

    Schmitt, Joseph M.; Adler, Desmond; Xu, Chenyang

    Since the first coronary angioplasty was performed in the late 1970s, imaging has played a central role in percutaneous coronary intervention (PCI). Today more than three million PCI procedures are performed worldwide to expand narrowed arteries and to clear blood clots that can cause debilitating symptoms of myocardial ischemia or fatal heart attacks. Although X-ray angiography is still the workhorse imaging modality in the field of interventional cardiology, intravascular imaging has become an indispensable tool for guiding complex PCI procedures. Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are the two most commonly used catheter-based imaging technologies in coronary procedures. Since the first commercial intravascular OCT systems were introduced in Japan and the European Union in 2004 and in the United States in 2009, the application of intravascular OCT has grown rapidly [3, 15, 16].

  19. Parametric Study of Radiator Concepts for a Stirling Radioisotope Power System Applicable to Deep Space Mission

    NASA Technical Reports Server (NTRS)

    Juhasz, Albert J.; Tew, Roy C.; Thieme, Lanny G.

    2000-01-01

    The Department of Energy (DOE) and the NASA Glenn Research Center are developing a Stirling converter for an advanced radioisotope power system to provide spacecraft onboard electric power for NASA deep space missions. This high-efficiency converter is being evaluated as an alternative to replace the much lower efficiency radioisotope thermoelectric generator (RTG). The current power requirement (six years after beginning of mission (BOM) for a mission to Jupiter) is 210 W(sub e) (watts electric) to be generated by two separate power systems, one on each side of the spacecraft. Both two-converter and four-converter system designs are being considered, depending on the amount of required redundancy.

  20. Evaluating the intensity of the acoustic radiation force impulse (ARFI) in intravascular ultrasound (IVUS) imaging: Preliminary in vitro results.

    PubMed

    Shih, Cho-Chiang; Lai, Ting-Yu; Huang, Chih-Chung

    2016-08-01

    The ability to measure the elastic properties of plaques and vessels is significant in clinical diagnosis, particularly for detecting a vulnerable plaque. A novel concept of combining intravascular ultrasound (IVUS) imaging and acoustic radiation force impulse (ARFI) imaging has recently been proposed. This method has potential in elastography for distinguishing between the stiffness of plaques and arterial vessel walls. However, the intensity of the acoustic radiation force requires calibration as a standard for the further development of an ARFI-IVUS imaging device that could be used in clinical applications. In this study, a dual-frequency transducer with 11MHz and 48MHz was used to measure the association between the biological tissue displacement and the applied acoustic radiation force. The output intensity of the acoustic radiation force generated by the pushing element ranged from 1.8 to 57.9mW/cm(2), as measured using a calibrated hydrophone. The results reveal that all of the acoustic intensities produced by the transducer in the experiments were within the limits specified by FDA regulations and could still displace the biological tissues. Furthermore, blood clots with different hematocrits, which have elastic properties similar to the lipid pool of plaques, with stiffness ranging from 0.5 to 1.9kPa could be displaced from 1 to 4μm, whereas the porcine arteries with stiffness ranging from 120 to 291kPa were displaced from 0.4 to 1.3μm when an acoustic intensity of 57.9mW/cm(2) was used. The in vitro ARFI images of the artery with a blood clot and artificial arteriosclerosis showed a clear distinction of the stiffness distributions of the vessel wall. All the results reveal that ARFI-IVUS imaging has the potential to distinguish the elastic properties of plaques and vessels. Moreover, the acoustic intensity used in ARFI imaging has been experimentally quantified. Although the size of this two-element transducer is unsuitable for IVUS imaging, the

  1. Progress in the Use of Isotopes: The Atomic Triad - Reactors, Radioisotopes and Radiation

    DOE R&D Accomplishments Database

    Libby, W. F.

    1958-08-04

    Recent years have seen a substantial growth in the use of isotopes in medicine, agriculture, and industry: up to the minute information on the production and use of isotopes in the U.S. is presented. The application of radioisotopes to industrial processes and manufacturing operations has expanded more rapidly than any one except its most ardent advocates expected. New uses and new users are numerous. The adoption by industry of low level counting techniques which make possible the use of carbon-14 and tritium in the control of industrial processes and in certain exploratory and research problems is perhaps most promising of current developments. The latest information on savings to industry will be presented. The medical application of isotopes has continued to develop at a rapid pace. The current trend appears to be in the direction of improvements in technique and the substitution of more effective isotopes for those presently in use. Potential and actual benefits accruing from the use of isotopes in agriculture are reviewed. The various methods of production of radioisotopes are discussed. Not only the present methods but also interesting new possibilities are covered. Although isotopes are but one of the many peaceful uses of the atom, it is the first to pay its way. (auth)

  2. Intravascular synovial sarcoma of the pulmonary artery with massive pleural effusion: report of a case with a favorable response to Ifosfamide chemotherapy and palliative radiation therapy.

    PubMed

    Maekura, Toshiya; Shimizu, Shigeki; Kawaguchi, Tomoya; Morimoto, Masahiro; Okuma, Tomohisa; Matsui, Hideo; Atagi, Shinji

    2015-01-01

    Synovial sarcoma (SS) commonly arises in the para-articular soft tissue; however, very few cases of intravascular SS have so far been reported. We herein describe a case of pulmonary artery SS with massive pleural effusion. A biopsy of the pleural lesions showed uniform short spindle cell proliferation, while the SYT-SSX fusion gene, which is preceded by chromosomal translocation t(X;18)(p11;q11), was detected using reverse transcription-polymerase chain reaction. Treatment with ifosfamide chemotherapy and palliative radiation therapy was effective in reducing the growth of the tumor in the pulmonary artery and pleural lesions, indicating that this regimen may be useful for the treatment of unresectable SS in the pulmonary artery. PMID:25948355

  3. Modular Stirling Radioisotope Generator

    NASA Technical Reports Server (NTRS)

    Schmitz, Paul C.; Mason, Lee S.; Schifer, Nicholas A.

    2016-01-01

    High-efficiency radioisotope power generators will play an important role in future NASA space exploration missions. Stirling Radioisotope Generators (SRGs) have been identified as a candidate generator technology capable of providing mission designers with an efficient, high-specific-power electrical generator. SRGs high conversion efficiency has the potential to extend the limited Pu-238 supply when compared with current Radioisotope Thermoelectric Generators (RTGs). Due to budgetary constraints, the Advanced Stirling Radioisotope Generator (ASRG) was canceled in the fall of 2013. Over the past year a joint study by NASA and the Department of Energy (DOE) called the Nuclear Power Assessment Study (NPAS) recommended that Stirling technologies continue to be explored. During the mission studies of the NPAS, spare SRGs were sometimes required to meet mission power system reliability requirements. This led to an additional mass penalty and increased isotope consumption levied on certain SRG-based missions. In an attempt to remove the spare power system, a new generator architecture is considered, which could increase the reliability of a Stirling generator and provide a more fault-tolerant power system. This new generator called the Modular Stirling Radioisotope Generator (MSRG) employs multiple parallel Stirling convertor/controller strings, all of which share the heat from the General Purpose Heat Source (GPHS) modules. For this design, generators utilizing one to eight GPHS modules were analyzed, which provided about 50 to 450 W of direct current (DC) to the spacecraft, respectively. Four Stirling convertors are arranged around each GPHS module resulting in from 4 to 32 Stirling/controller strings. The convertors are balanced either individually or in pairs, and are radiatively coupled to the GPHS modules. Heat is rejected through the housing/radiator, which is similar in construction to the ASRG. Mass and power analysis for these systems indicate that specific

  4. Radiation protection potential of MOX-fuel doped with 231Pa and Cs radioisotopes.

    PubMed

    Kryuchkov, E F; Glebov, V B; Apse, V A; Shmelev, A N

    2005-01-01

    The paper addresses the problem of MOX-fuel self-protection during full cycle of MOX-fuel management. Under conditions of the closed LWR cycle the proliferation-resistance levels were evaluated for fresh and spent MOX-fuel with 231Pa and Cs feed. As it follows from the paper results, combination of these two admixtures being doped into MOX-fuel is able to enhance the inherent radiation barrier and to weaken shortcomings of both proliferation deterrents.

  5. Radiation protection potential of MOX-fuel doped with 231Pa and Cs radioisotopes.

    PubMed

    Kryuchkov, E F; Glebov, V B; Apse, V A; Shmelev, A N

    2005-01-01

    The paper addresses the problem of MOX-fuel self-protection during full cycle of MOX-fuel management. Under conditions of the closed LWR cycle the proliferation-resistance levels were evaluated for fresh and spent MOX-fuel with 231Pa and Cs feed. As it follows from the paper results, combination of these two admixtures being doped into MOX-fuel is able to enhance the inherent radiation barrier and to weaken shortcomings of both proliferation deterrents. PMID:16381734

  6. Radiation safety aspects of production of commercial levels of medical radioisotopes

    NASA Astrophysics Data System (ADS)

    Boothe, T. E.; McLeod, T. F.; Fernandez-Rubio, F.

    1993-06-01

    The first step toward efficient radiation safety in a facility that intends to produce commercial levels of radionuclides is to nticipate the scope of the facility during the design stages of the physical plant and during formulation of operating procedures. The design and operation must include flexibility to accommodate changing needs of production and research and development while providing radiation safety. A recently proposed licensing guide from the Bureau of Radiation Control, Texas Department of Health, while providing for safe operation, would severely limit flexibility and development. For example, engineering controls and procedures should be specified for generic systems as opposed to each specific radionuclide and by-products. Operator training is critical for reduced exposure and should be addressed, but requiring prior training for all operators is not reasonably achievable and would result in loss of proprietary information. Procedures to reduce exposure should include experimentally determined "cooldown" times, "problem indexes" for specific jobs related to particular cyclotrons, and proper management and administrative structures.

  7. Naturally induced secondary radiation in interplanetary space: Preliminary analyses for gamma radiation and radioisotope production from thermal neutron activation

    NASA Technical Reports Server (NTRS)

    Plaza-Rosado, Heriberto

    1991-01-01

    Thermal neutron activation analyses were carried out for various space systems components to determine gamma radiation dose rates and food radiation contamination levels. The space systems components selected were those for which previous radiation studies existed. These include manned space vehicle radiation shielding, liquid hydrogen propellant tanks for a Mars mission, and a food supply used as space vehicle radiation shielding. The computational method used is based on the fast neutron distribution generated by the BRYNTRN and HZETRN transport codes for Galactic Cosmic Rays (GCR) at solar minimum conditions and intense solar flares in space systems components. The gamma dose rates for soft tissue are calculated for water and aluminum space vehicle slab shields considering volumetric source self-attenuation and exponential buildup factors. In the case of the lunar habitat with regolith shielding, a completely exposed spherical habitat was assumed for mathematical convenience and conservative calculations. Activation analysis of the food supply used as radiation shielding is presented for four selected nutrients: potassium, calcium, sodium, and phosphorus. Radioactive isotopes that could represent a health hazard if ingested are identified and their concentrations are identified. For nutrients soluble in water, it was found that all induced radioactivity was below the accepted maximum permissible concentrations.

  8. Modular Stirling Radioisotope Generator

    NASA Technical Reports Server (NTRS)

    Schmitz, Paul C.; Mason, Lee S.; Schifer, Nicholas A.

    2015-01-01

    High efficiency radioisotope power generators will play an important role in future NASA space exploration missions. Stirling Radioisotope Generators (SRG) have been identified as a candidate generator technology capable of providing mission designers with an efficient, high specific power electrical generator. SRGs high conversion efficiency has the potential to extend the limited Pu-238 supply when compared with current Radioisotope Thermoelectric Generators (RTG). Due to budgetary constraints, the Advanced Stirling Radioisotope Generator (ASRG) was canceled in the fall of 2013. Over the past year a joint study by NASA and DOE called the Nuclear Power Assessment Study (NPAS) recommended that Stirling technologies continue to be explored. During the mission studies of the NPAS, spare SRGs were sometimes required to meet mission power system reliability requirements. This led to an additional mass penalty and increased isotope consumption levied on certain SRG-based missions. In an attempt to remove the spare power system, a new generator architecture is considered which could increase the reliability of a Stirling generator and provide a more fault-tolerant power system. This new generator called the Modular Stirling Radioisotope Generator (MSRG) employs multiple parallel Stirling convertor/controller strings, all of which share the heat from the General Purpose Heat Source (GPHS) modules. For this design, generators utilizing one to eight GPHS modules were analyzed, which provide about 50 to 450 watts DC to the spacecraft, respectively. Four Stirling convertors are arranged around each GPHS module resulting in from 4 to 32 Stirling/controller strings. The convertors are balanced either individually or in pairs, and are radiatively coupled to the GPHS modules. Heat is rejected through the housing/radiator which is similar in construction to the ASRG. Mass and power analysis for these systems indicate that specific power may be slightly lower than the ASRG and

  9. Prospects for using implanted systems of assisted circulation and artificial heart with a radioisotope power source (biomedical, thermal, and radiation aspects).

    PubMed

    Kiselev, I M; Dubrovskiĭ, G P; Mosidze, T G; Bazhanov, A Iu

    1983-02-01

    The capacity of dogs to diffuse heat (up to 50 W) from an artificial heart and to tolerate prolonged intracorporeal ionizing radiation from a radioisotope power source (238Pu) was investigated, using electrical models of vascular blood heat exchangers that permit reproduction of elimination and heat transmission in autonomous systems. It was shown that up to 50 W can be discharged at temperatures of the wall-blood interface that do not exceed 43 degrees C. Clotting indexes, concentration of total protein, hemolysis, and serum enzyme activity during 1-1.5 months of heating remained within physiologically normal limits. A specific power load of up to 1.5 W/kg at ambient temperatures of 18-20 degrees C revealed no evidence of changes in heat production. By measuring the distribution of power of the dose absorbed around a 45-W plutonium source it was possible to estimate dose loads on critical organs and to assess overall risk of death from malignant tumors induced by radiation over a 10-year period: 6-12% for males and 8-14% for females. It is not very probable that use of the artificial heart with a radioisotope power source will be limited by thermal and radiational effects. PMID:6838399

  10. Disseminated intravascular coagulation (DIC)

    MedlinePlus

    Levi M. Disseminated intravascular coagulation. In: Hoffman R, Benz EJ Jr, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice . 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap ...

  11. Nuclear medicine practices in the 1950s through the mid-1970s and occupational radiation doses to technologists from diagnostic radioisotope procedures.

    PubMed

    Drozdovitch, Vladimir; Brill, Aaron B; Mettler, Fred A; Beckner, William M; Goldsmith, Stanley J; Gross, Milton D; Hays, Marguerite T; Kirchner, Peter T; Langan, James K; Reba, Richard C; Smith, Gary T; Bouville, André; Linet, Martha S; Melo, Dunstana R; Lee, Choonsik; Simon, Steven L

    2014-10-01

    Data on occupational radiation exposure from nuclear medicine procedures for the time period of the 1950s through the 1970s is important for retrospective health risk studies of medical personnel who conducted those activities. However, limited information is available on occupational exposure received by physicians and technologists who performed nuclear medicine procedures during those years. To better understand and characterize historical radiation exposures to technologists, the authors collected information on nuclear medicine practices in the 1950s, 1960s, and 1970s. To collect historical data needed to reconstruct doses to technologists, a focus group interview was held with experts who began using radioisotopes in medicine in the 1950s and the 1960s. Typical protocols and descriptions of clinical practices of diagnostic radioisotope procedures were defined by the focus group and were used to estimate occupational doses received by personnel, per nuclear medicine procedure, conducted in the 1950s to 1960s using radiopharmaceuticals available at that time. The radionuclide activities in the organs of the reference patient were calculated using the biokinetic models described in ICRP Publication 53. Air kerma rates as a function of distance from a reference patient were calculated by Monte Carlo radiation transport calculations using a hybrid computational phantom. Estimates of occupational doses to nuclear medicine technologists per procedure were found to vary from less than 0.01 μSv (thyroid scan with 1.85 MBq of administered I-iodide) to 0.4 μSv (brain scan with 26 MBq of Hg-chlormerodin). Occupational doses for the same diagnostic procedures starting in the mid-1960s but using Tc were also estimated. The doses estimated in this study show that the introduction of Tc resulted in an increase in occupational doses per procedure.

  12. NUCLEAR MEDICINE PRACTICES IN THE 1950s THROUGH THE mid-1970s AND OCCUPATIONAL RADIATION DOSES TO TECHNOLOGISTS FROM DIAGNOSTIC RADIOISOTOPE PROCEDURES

    PubMed Central

    Drozdovitch, Vladimir; Brill, Aaron B.; Mettler, Fred A.; Beckner, William M.; Goldsmith, Stanley J.; Gross, Milton D.; Hays, Marguerite T.; Kirchner, Peter T.; Langan, James K.; Reba, Richard C.; Smith, Gary T.; Bouville, André; Linet, Martha S.; Melo, Dunstana R.; Lee, Choonsik; Simon, Steven L.

    2014-01-01

    Data on occupational radiation exposure from nuclear medicine procedures for the time period of the 1950s through the 1970s is important for retrospective health risk studies of medical personnel who conducted those activities. However, limited information is available on occupational exposure received by physicians and technologists who performed nuclear medicine procedures during those years. To better understand and characterize historical radiation exposures to technologists, we collected information on nuclear medicine practices in the 1950s, 1960s, and 1970s. To collect historical data needed to reconstruct doses to technologists, a focus group interview was held with experts who began using radioisotopes in medicine in the 1950s and the 1960s. Typical protocols and descriptions of clinical practices of diagnostic radioisotope procedures were defined by the focus group and were used to estimate occupational doses received by personnel, per nuclear medicine procedure, conducted in the 1950s-1960s using radiopharmaceuticals available at that time. The radionuclide activities in the organs of the reference patient were calculated using the biokinetic models described in ICRP Publication 53. Air kerma rates as a function of distance from a reference patient were calculated by Monte Carlo radiation transport calculations using a hybrid computational phantom. Estimates of occupational doses to nuclear medicine technologists per procedure were found to vary from less than 0.01 μSv (thyroid scan with 1.85 MBq of administered 131I-iodide) to 0.4 μSv (brain scan with 26 MBq of 203Hg-chlormerodin). Occupational doses for the same diagnostic procedures starting in the mid-1960s but using 99mTc were also estimated. The doses estimated in this study show that the introduction of 99mTc resulted in an increase in occupational doses per procedure. PMID:25162420

  13. Silicon Carbide Radioisotope Batteries

    NASA Technical Reports Server (NTRS)

    Rybicki, George C.

    2005-01-01

    The substantial radiation resistance and large bandgap of SiC semiconductor materials makes them an attractive candidate for application in a high efficiency, long life radioisotope battery. To evaluate their potential in this application, simulated batteries were constructed using SiC diodes and the alpha particle emitter Americium Am-241 or the beta particle emitter Promethium Pm-147. The Am-241 based battery showed high initial power output and an initial conversion efficiency of approximately 16%, but the power output decayed 52% in 500 hours due to radiation damage. In contrast the Pm-147 based battery showed a similar power output level and an initial conversion efficiency of approximately 0.6%, but no degradation was observed in 500 hours. However, the Pm-147 battery required approximately 1000 times the particle fluence as the Am-242 battery to achieve a similar power output. The advantages and disadvantages of each type of battery and suggestions for future improvements will be discussed.

  14. Infections and intravascular devices.

    PubMed

    Elliott, T S; Faroqui, M H

    Complications associated with intravascular devices include infections mainly caused by Staphylococcus epidermis and S. aureus. The reported incidence of these infections varies. Several factors influence the propensity for catheter infections. We recommend strategies for the prevention and treatment of catheter-related sepsis. PMID:1422561

  15. Intravascular Photoacoustic Imaging

    PubMed Central

    Wang, Bo; Su, Jimmy L.; Karpiouk, Andrei B.; Sokolov, Konstantin V.; Smalling, Richard W.; Emelianov, Stanislav Y.

    2011-01-01

    Intravascular photoacoustic (IVPA) imaging is a catheter-based, minimally invasive, imaging modality capable of providing high-resolution optical absorption map of the arterial wall. Integrated with intravascular ultrasound (IVUS) imaging, combined IVPA and IVUS imaging can be used to detect and characterize atherosclerotic plaques building up in the inner lining of an artery. In this paper, we present and discuss various representative applications of combined IVPA/IVUS imaging of atherosclerosis, including assessment of the composition of atherosclerotic plaques, imaging of macrophages within the plaques, and molecular imaging of biomarkers associated with formation and development of plaques. In addition, imaging of coronary artery stents using IVPA and IVUS imaging is demonstrated. Furthermore, the design of an integrated IVUS/IVPA imaging catheter needed for in vivo clinical applications is discussed. PMID:21359138

  16. How Is Disseminated Intravascular Coagulation Treated?

    MedlinePlus

    ... the NHLBI on Twitter. How Is Disseminated Intravascular Coagulation Treated? Treatment for disseminated intravascular coagulation (DIC) depends ... and treat the underlying cause. Acute Disseminated Intravascular Coagulation People who have acute DIC may have severe ...

  17. Disseminated intravascular coagulation.

    PubMed

    Gando, Satoshi; Levi, Marcel; Toh, Cheng-Hock

    2016-01-01

    Disseminated intravascular coagulation (DIC) is an acquired syndrome characterized by widespread intravascular activation of coagulation that can be caused by infectious insults (such as sepsis) and non-infectious insults (such as trauma). The main pathophysiological mechanisms of DIC are inflammatory cytokine-initiated activation of tissue factor-dependent coagulation, insufficient control of anticoagulant pathways and plasminogen activator inhibitor 1-mediated suppression of fibrinolysis. Together, these changes give rise to endothelial dysfunction and microvascular thrombosis, which can cause organ dysfunction and seriously affect patient prognosis. Recent observations have pointed to an important role for extracellular DNA and DNA-binding proteins, such as histones, in the pathogenesis of DIC. The International Society on Thrombosis and Haemostasis (ISTH) established a DIC diagnostic scoring system consisting of global haemostatic test parameters. This scoring system has now been well validated in diverse clinical settings. The theoretical cornerstone of DIC management is the specific and vigorous treatment of the underlying conditions, and DIC should be simultaneously managed to improve patient outcomes. The ISTH guidance for the treatment of DIC recommends treatment strategies that are based on current evidence. In this Primer, we provide an updated overview of the pathophysiology, diagnosis and management of DIC and discuss the future directions of basic and clinical research in this field. PMID:27250996

  18. Radioisotope powered AMTEC systems

    NASA Astrophysics Data System (ADS)

    Ivanenok, Joseph F., III; Sievers, Robert K.

    1994-11-01

    Alkali metal thermal to electric converter (AMTEC) systems are being developed for high performance spacecraft power systems, including small, general purpose heat source (GPHS) powered systems. Several design concepts have been evaluated for the power range from 75 W to 1 kW. The specific power for these concepts has been found to be as high as 18-20 W/kg and 22 kW/m(exp 3). The projected area, including radiators, has been as low as 0.4 m(exp 2)/kW. AMTEC power systems are extremely attractive, relative to other current and projected power systems, because AMTEC offers high power density, low projected area, and low volume. Two AMTEC cell design types have been identified. A single-tube cell is already under development and a multitube cell design, to provide additional power system gains, has undergone proof-of-principle testing. Solar powered AMTEC (SAMTEC) systems are also being developed, and numerous terrestrial applications have been identified for which the same basic AMTEC cells being developed for radioisotope systems are also suitable.

  19. Radioisotopic heat source

    DOEpatents

    Sayell, E.H.

    1973-10-23

    A radioisotopic heat source is described which includes a core of heat productive, radioisotopic material, an impact resistant layer of graphite surrounding said core, and a shell of iridium metal intermediate the core and the impact layer. The source may also include a compliant mat of iridium between the core and the iridium shell, as well as an outer covering of iridium metal about the entire heat source. (Official Gazette)

  20. Safe radioisotope thermoelectric generators and heat sources for space applications

    NASA Astrophysics Data System (ADS)

    O'Brien, R. C.; Ambrosi, R. M.; Bannister, N. P.; Howe, S. D.; Atkinson, H. V.

    2008-07-01

    Several isotopes are examined as alternatives to 238Pu that is traditionally used in radioisotope thermoelectric generators (RTGs) and heating units (RHUs). The radioisotopes discussed include 241Am, 208Po, 210Po, and 90Sr. The aim of this study is to facilitate the design of an RTG with a minimal radiation dose rate and mass including any required shielding. Applications of interest are primarily space and planetary exploration. In order to evaluate the properties of the alternative radioisotopes a Monte Carlo model was developed to examine the radiation protection aspect of the study. The thermodynamics of the power generation process is examined and possible materials for the housing and encapsulation of the radioisotopes are proposed. In this study we also present a historical review of radioisotope thermoelectric generators (RTGs) and the thermoelectric conversion mechanism in order to provide a direct comparison with the performance of our proposed alternative isotope systems.

  1. BEST medical radioisotope production cyclotrons

    SciTech Connect

    Sabaiduc, Vasile; Milton, Bruce; Suthanthiran, Krishnan; Johnson, Richard R.; Gelbart, W. Z.

    2013-04-19

    Best Cyclotron Systems Inc (BCSI) is currently developing 14 MeV, 25 MeV, 35MeV and 70MeV cyclotrons for radioisotope production and research applications as well as the entire spectrum of targets and nuclear synthesis modules for the production of Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT) and radiation therapy isotopes. The company is a subsidiary of Best Medical International, renowned in the field of medical instrumentation and radiation therapy. All cyclotrons have external negative hydrogen ion sources, four radial sectors with two dees in opposite valleys, cryogenic vacuum system and simultaneous beam extraction on opposite lines. The beam intensity ranges from 400 {mu}A to 1000 {mu}A, depending on the cyclotron energy and application.

  2. Intravascular adenomyomatosis: expanding the morphologic spectrum of intravascular leiomyomatosis.

    PubMed

    Hirschowitz, Lynn; Mayall, Frederick G; Ganesan, Raji; McCluggage, W Glenn

    2013-09-01

    Intravascular leiomyomatosis (IVL) is characterized by the presence of smooth muscle in venous and lymphatic spaces within the myometrium. Although the intravascular component usually consists solely of typical smooth muscle or variants of smooth muscle differentiation, we report 5 cases in which the intravascular component also included endometrioid glandular and stromal elements. We propose the term "intravenous adenomyomatosis" to describe this unusual variant of IVL. The mean age of the patients in this series was 50.2 years, slightly older than that of patients with conventional IVL. In addition to intravenous adenomyomatosis, both adenomyosis and leiomyomas were identified in all of our cases, supporting the hypothesis that the intravascular smooth muscle component in IVL is derived from associated myometrial pathology rather than from vessel walls. In our series, intravenous adenomyomatosis had a similar benign clinical behavior to most cases of IVL with no metastatic or recurrent disease identified at follow-up in 4 cases for which follow-up information was available. The main differential diagnoses are adenomyosis with vascular involvement, low-grade endometrial stromal sarcoma (ESS), including ESS with smooth muscle and glandular differentiation, and adenosarcoma with lymphovascular invasion. The possibility of intravenous adenomyomatosis should be borne in mind when considering these diagnoses, particularly ESS and adenosarcoma, which have different implications for patient management and prognosis.

  3. Cyclotron Production of Medical Radioisotopes

    SciTech Connect

    Avila-Rodriguez, M. A.; Zarate-Morales, A.; Flores-Moreno, A.

    2010-08-04

    The cyclotron production of radioisotopes for medical applications is gaining increased significance in diagnostic molecular imaging techniques such as PET and SPECT. In this regard, radioisotope production has never been easier or more convenient until de introduction of compact medical cyclotrons in the last few decades, which allowed the use of short-lived radioisotopes in in vivo nuclear medicine studies on a routine basis. This review outlines some general considerations about the production of radioisotopes using charged particle accelerators.

  4. Radioisotopic heat source

    DOEpatents

    Jones, G.J.; Selle, J.E.; Teaney, P.E.

    1975-09-30

    Disclosed is a radioisotopic heat source and method for a long life electrical generator. The source includes plutonium dioxide shards and yttrium or hafnium in a container of tantalum-tungsten-hafnium alloy, all being in a nickel alloy outer container, and subjected to heat treatment of from about 1570$sup 0$F to about 1720$sup 0$F for about one h. (auth)

  5. Miniature Radioisotope Power Source

    NASA Technical Reports Server (NTRS)

    Chmielewski, Artur B.

    1995-01-01

    Proposed miniature power source generates electricity for years from heat developed in small radioisotope unit without addition of fuel or dependence on sunlight. Called powerstick, is relatively inexpensive, lightweight, and rugged. Supplies power to small vehicles or scientific instruments in remote locations on Earth or in outer space. Envisioned uses include Mars miniature rovers and monitoring equipment for toxic or nuclear storage sites.

  6. Radioisotopes as Political Instruments, 1946-1953.

    PubMed

    Creager, Angela N H

    2009-01-01

    The development of nuclear "piles," soon called reactors, in the Manhattan Project provided a new technology for manufacturing radioactive isotopes. Radioisotopes, unstable variants of chemical elements that give off detectable radiation upon decay, were available in small amounts for use in research and therapy before World War II. In 1946, the U.S. government began utilizing one of its first reactors, dubbed X-10 at Oak Ridge, as a production facility for radioisotopes available for purchase to civilian institutions. This program of the U.S. Atomic Energy Commission was meant to exemplify the peacetime dividends of atomic energy. The numerous requests from scientists outside the United States, however, sparked a political debate about whether the Commission should or even could export radioisotopes. This controversy manifested the tension in U.S. politics between scientific internationalism as a tool of diplomacy, associated with the aims of the Marshall Plan, and the desire to safeguard the country's atomic monopoly at all costs, linked to American anti-Communism. This essay examines the various ways in which radioisotopes were used as political instruments-both by the U.S. federal government in world affairs, and by critics of the civilian control of atomic energy-in the early Cold War.

  7. Radioisotopes as Political Instruments, 1946-1953.

    PubMed

    Creager, Angela N H

    2009-01-01

    The development of nuclear "piles," soon called reactors, in the Manhattan Project provided a new technology for manufacturing radioactive isotopes. Radioisotopes, unstable variants of chemical elements that give off detectable radiation upon decay, were available in small amounts for use in research and therapy before World War II. In 1946, the U.S. government began utilizing one of its first reactors, dubbed X-10 at Oak Ridge, as a production facility for radioisotopes available for purchase to civilian institutions. This program of the U.S. Atomic Energy Commission was meant to exemplify the peacetime dividends of atomic energy. The numerous requests from scientists outside the United States, however, sparked a political debate about whether the Commission should or even could export radioisotopes. This controversy manifested the tension in U.S. politics between scientific internationalism as a tool of diplomacy, associated with the aims of the Marshall Plan, and the desire to safeguard the country's atomic monopoly at all costs, linked to American anti-Communism. This essay examines the various ways in which radioisotopes were used as political instruments-both by the U.S. federal government in world affairs, and by critics of the civilian control of atomic energy-in the early Cold War. PMID:20725612

  8. Radioisotopes as Political Instruments, 1946–1953

    PubMed Central

    Creager, Angela N. H.

    2009-01-01

    The development of nuclear “piles,” soon called reactors, in the Manhattan Project provided a new technology for manufacturing radioactive isotopes. Radioisotopes, unstable variants of chemical elements that give off detectable radiation upon decay, were available in small amounts for use in research and therapy before World War II. In 1946, the U.S. government began utilizing one of its first reactors, dubbed X-10 at Oak Ridge, as a production facility for radioisotopes available for purchase to civilian institutions. This program of the U.S. Atomic Energy Commission was meant to exemplify the peacetime dividends of atomic energy. The numerous requests from scientists outside the United States, however, sparked a political debate about whether the Commission should or even could export radioisotopes. This controversy manifested the tension in U.S. politics between scientific internationalism as a tool of diplomacy, associated with the aims of the Marshall Plan, and the desire to safeguard the country’s atomic monopoly at all costs, linked to American anti-Communism. This essay examines the various ways in which radioisotopes were used as political instruments—both by the U.S. federal government in world affairs, and by critics of the civilian control of atomic energy—in the early Cold War. PMID:20725612

  9. Improved dosimetry techniques for intravascular brachytherapy

    NASA Astrophysics Data System (ADS)

    Sehgal, Varun

    Coronary artery disease leads to the accumulation of atheromatous plaque leading to coronary stenosis. Coronary intervention techniques such as balloon angioplasty and atherectomy are used to address coronary stenosis and establish a stable lumen thus enhancing blood flow to the myocardium. Restenosis or re-blockage of the arteries is a major limitation of the above mentioned interventional techniques. Neointimal hyperplasia or proliferation of cells in response to the vascular injury as a result of coronary intervention is considered to be one of the major causes of restenosis. Recent studies indicated that irradiation of the coronary lesion site, with radiation doses ranging from 15 to 30 Gy, leads to diminishing neointimal hyperplasia with subsequent reduction in restenosis. The radiation dose is given by catheter-based radiation delivery systems using beta-emitters 90Sr/90Y, 32P and gamma-emitting 192Ir among others. However the dose schema used for dose prescription for these sources are relatively simplistic, and are based on calculations using uniform homogenous water or tissue media and simple cylinder geometry. Stenotic coronary vessels are invariably lined with atheromatous plaque of heterogeneous composition, the radiation dose distribution obtained from such dosimetry data can cause significant variations in the actual dose received by a given patient. Such discrepancies in dose calculation can introduce relatively large uncertainties in the limits of dose window for effective and safe application of intravascular brachytherapy, and consequently in the clinical evaluation of the efficacy of this modality. In this research study we investigated the effect of different geometrical and material heterogeneities, including residual plaque, catheter non-centering, lesion eccentricity and cardiac motion on the radiation dose delivered at the lesion site. Correction factors including dose perturbation factors and dose variation factors have been calculated

  10. Safe use of radioisotopes.

    PubMed

    Meisenhelder, J; Semba, K

    2001-05-01

    The use of radioisotopes to label specific molecules in a defined way has greatly advanced the discovery and dissection of biochemical pathways. The development of methods to inexpensively synthesize such tagged biological compounds on an industrial scale has enabled them to be used routinely in laboratory protocols, including many detailed in this manual. Although most of these protocols involve the use of only microcurie (mCi) amounts of radioactivity, some (particularly those describing the metabolic labeling of proteins or nucleic acids within cells) require amounts on the order of millicuries (mCi). In all cases where radioisotopes are used, depending on the quantity and nature of the isotope, certain precautions must be taken to ensure the safety of the investigator. It is essential to use good safety practices and proper protection to handle radioactive substances. This unit discusses storage, handling, and disposal of 35S, 32P, 33P, and 125I. PMID:18228276

  11. Safe use of radioisotopes.

    PubMed

    Meisenhelder, Jill; Semba, Kentaro

    2006-09-01

    The use of radioisotopes to label specific molecules in a defined way has greatly furthered the discovery and dissection of biochemical pathways. The development of methods to synthesize such tagged biological compounds inexpensively on an industrial scale has enabled them to be used routinely in laboratory protocols, including many detailed in this manual. Although most of these protocols involve the use of only microcurie amounts of radioactivity, some (particularly those describing the metabolic labeling of proteins or nucleic acids within cells) require amounts on the order of millicuries. In all cases where radioisotopes are used, depending on the quantity and nature of the isotope, certain precautions must be taken to ensure the safety of the scientist. It is essential to use good safety practices and proper protection to handle radioactive substances. This unit discusses handling, storage, and disposal of the isotopes most frequently used in biological research. PMID:18432960

  12. Taming Highly Charged Radioisotopes

    NASA Astrophysics Data System (ADS)

    Chowdhury, Usman; Eberhardt, Benjamin; Jang, Fuluni; Schultz, Brad; Simon, Vanessa; Delheij, Paul; Dilling, Jens; Gwinner, Gerald

    2012-10-01

    The precise and accurate mass of short-lived radioisotopes is a very important parameter in physics. Contribution to the improvement of nuclear models, metrological standard fixing and tests of the unitarity of the Caibbibo-Kobayashi-Maskawa (CKM) matrix are a few examples where the mass value plays a major role. TRIUMF's ion trap for atomic and nuclear physics (TITAN) is a unique facility of three online ion traps that enables the mass measurement of short-lived isotopes with high precision (˜10-8). At present TITAN's electron beam ion trap (EBIT) increases the charge state to increase the precision, but there is no facility to significantly reduce the energy spread introduced by the charge breeding process. The precision of the measured mass of radioisotopes is linearly dependent on the charge state while the energy spread of the charged radioisotopes affects the precision adversely. To boost the precision level of mass measurement at TITAN without loosing too many ions, a cooler Penning trap (CPET) is being developed. CPET is designed to use either positively (proton) or negatively (electron) charged particles to reduce the energy spread via sympathetic cooling. Off-line setup of CPET is complete. Details of the working principles and updates are presented

  13. Endosulfan poisoning with intravascular hemolysis.

    PubMed

    Ramaswamy, Shankar; Puri, Goverdhan Dutt; Rajeev, Subramanyam

    2008-04-01

    We describe a 26-year-old female patient, who had attempted suicide with Endosulfan, and who presented to the Emergency Department with status epilepticus. She subsequently developed hypotension refractory to inotropes, intravascular hemolysis, disseminated intravascular coagulation (DIC), metabolic acidosis and, finally, cardiac arrest and death. Endosulfan is a chlorinated insecticide that causes central nervous system hyperstimulation. It is absorbed from the gastrointestinal tract, skin, and respiratory tract, and leads to nausea, vomiting, paraesthesia, giddiness, convulsion, coma, respiratory failure, and congestive cardiac failure. Hepatic, renal and myocardial toxicity, agranulocytosis, aplastic anemia, cerebral edema, DIC, thrombocytopenia, and skin reaction also have been reported. Management includes decontamination of skin and gastrointestinal tract, supportive care including treatment of status epilepticus, dysrhythmias, and mechanical ventilation. Mortality and morbidity rates are very high and there is no specific antidote. Atropine and catecholamines should be avoided.

  14. Image Processing in Intravascular OCT

    NASA Astrophysics Data System (ADS)

    Wang, Zhao; Wilson, David L.; Bezerra, Hiram G.; Rollins, Andrew M.

    Coronary artery disease is the leading cause of death in the world. Intravascular optical coherence tomography (IVOCT) is rapidly becoming a promising imaging modality for characterization of atherosclerotic plaques and evaluation of coronary stenting. OCT has several unique advantages over alternative technologies, such as intravascular ultrasound (IVUS), due to its better resolution and contrast. For example, OCT is currently the only imaging modality that can measure the thickness of the fibrous cap of an atherosclerotic plaque in vivo. OCT also has the ability to accurately assess the coverage of individual stent struts by neointimal tissue over time. However, it is extremely time-consuming to analyze IVOCT images manually to derive quantitative diagnostic metrics. In this chapter, we introduce some computer-aided methods to automate the common IVOCT image analysis tasks.

  15. Advanced Radioisotope Power Conversion Technology Research and Development

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.

    2004-01-01

    NASA's Radioisotope Power Conversion Technology program is developing next generation power conversion technologies that will enable future missions that have requirements that cannot be met by either the ubiquitous photovoltaic systems or by current Radioisotope Power System (RPS) technology. Performance goals of advanced radioisotope power systems include improvement over the state-of-practice General Purpose Heat Source/Radioisotope Thermoelectric Generator by providing significantly higher efficiency to reduce the number of radioisotope fuel modules, and increase specific power (watts/kilogram). Other Advanced RPS goals include safety, long-life, reliability, scalability, multi-mission capability, resistance to radiation, and minimal interference with the scientific payload. NASA has awarded ten contracts in the technology areas of Brayton, Stirling, Thermoelectric, and Thermophotovoltaic power conversion including five development contracts that deal with more mature technologies and five research contracts. The Advanced RPS Systems Assessment Team includes members from NASA GRC, JPL, DOE and Orbital Sciences whose function is to review the technologies being developed under the ten Radioisotope Power Conversion Technology contracts and assess their relevance to NASA's future missions. Presented is an overview of the ten radioisotope power conversion technology contracts and NASA's Advanced RPS Systems Assessment Team.

  16. Plastic Gamma Sensors: An Application in Detection of Radioisotopes

    SciTech Connect

    S. Mukhopadhyay

    2003-06-01

    A brief survey of plastic scintillators for various radiation measurement applications is presented here. The utility of plastic scintillators for practical applications such as gamma radiation monitoring, real-time radioisotope detection and screening is evaluated in laboratory and field measurements. This study also reports results of Monte Carlo-type predictive responses of common plastic scintillators in gamma and neutron radiation fields. Small-size plastic detectors are evaluated for static and dynamic gamma-ray detection sensitivity of selected radiation sources.

  17. Alternative Radioisotopes for Heat and Power Sources

    NASA Astrophysics Data System (ADS)

    Tinsley, T.; Sarsfield, M.; Rice, T.

    Production of 238Pu requires considerable facilities including a nuclear reactor and reprocessing plants that are very expensive to build and operate. Thus, a more economical alternative is very attractive to the industry. There are many alternative radioisotopes that exist but few that satisfy the criteria of performance, availability and cost to produce. Any alternative to 238Pu must exist in a chemical form that is compatible with the materials required to safely encapsulate the heat source at the high temperatures of operation and potential launch failure scenarios. The chemical form must also have suitable thermal properties to ensure maximum energy conversion efficiencies when integrated into radioisotope thermoelectric generators over the required mission durations. In addition, the radiation dose must be low enough for operators during production and not so prohibitive that excessive shielding mass is required on the space craft. This paper will focus on the preferred European alternative of 241Am, and the issues that will need to be addressed.

  18. A facility to remotely assemble radioisotope thermoelectric generators

    SciTech Connect

    Engstrom, J.W.; Goldmann, L.H.; Truitt, R.W.

    1992-07-01

    Radioisotope Thermoelectric Generators (RTGs) are electrical power sources that use heat from decaying radioisotopes to directly generate electrical power. The RTG assembly process is performed in an inert atmosphere inside a large glovebox, which is surrounded by radiation shielding to reduce exposure to neutron and gamma radiation from the radioisotope heat source. In the past, allowable dose rate limits have allowed direct, manual assembly methods; however, current dose rate limits require a thicker radiation shielding that makes direct, manual assembly infeasible. To minimize RTG assembly process modifications, telerobotic systems are being investigated to perform remote assembly tasks. Telerobotic systems duplicate human arm motion and incorporate force feedback sensitivity to handle objects and tools in a human-like manner. A telerobotic system with two arms and a three-dimensional (3-D) vision system can be used to perform remote RTG assembly tasks inside gloveboxes and cells using unmodified, normal hand tools.

  19. Fibrinolysis in disseminated intravascular coagulation.

    PubMed

    Hack, C E

    2001-12-01

    Studies in experimental models for sepsis, the most common cause of disseminated intravascular coagulation (DIC), have put forward the concept of a procoagulant state that is characterized by thrombin generation exceeding that of plasmin. Convincing evidence indicates that this imbalance between coagulation and fibrinolysis is due to increased levels of plasminogen activator inhibitor type 1 (PAI-1). Levels of this fibrinolysis inhibitor indeed correlate with outcome and severity of multiple organ failure in patients with sepsis, as well as in patients with DIC from other causes. Hence we suggest that PAI-1 constitutes an important target for therapy in patients with DIC.

  20. Radioisotope Power System Pool Concept

    NASA Technical Reports Server (NTRS)

    Rusick, Jeffrey J.; Bolotin, Gary S.

    2015-01-01

    Advanced Radioisotope Power Systems (RPS) for NASA deep space science missions have historically used static thermoelectric-based designs because they are highly reliable, and their radioisotope heat sources can be passively cooled throughout the mission life cycle. Recently, a significant effort to develop a dynamic RPS, the Advanced Stirling Radioisotope Generator (ASRG), was conducted by NASA and the Department of Energy, because Stirling based designs offer energy conversion efficiencies four times higher than heritage thermoelectric designs; and the efficiency would proportionately reduce the amount of radioisotope fuel needed for the same power output. However, the long term reliability of a Stirling based design is a concern compared to thermoelectric designs, because for certain Stirling system architectures the radioisotope heat sources must be actively cooled via the dynamic operation of Stirling converters throughout the mission life cycle. To address this reliability concern, a new dynamic Stirling cycle RPS architecture is proposed called the RPS Pool Concept.

  1. Acute Disseminated Intravascular Coagulation in Neuroendocrine Carcinoma

    PubMed Central

    Teh, Ru-Wen; Tsoi, Daphne T.

    2012-01-01

    Malignancy is a common cause of disseminated intravascular coagulation and usually presents as a chronic disorder in solid organ tumours. We present a rare case of recurrent acute disseminated intravascular coagulation in neuroendocrine carcinoma after manipulation, firstly, by core biopsy and, later, by cytotoxic therapy causing a release of procoagulants and cytokines from lysed tumour cells. This is reminiscent of tumour lysis syndrome where massive quantities of intracellular electrolytes and nucleic acid are released, causing acute metabolic imbalance and renal failure. This case highlights the potential complication of acute disseminated intravascular coagulation after trauma to malignant cells. PMID:23139666

  2. Disseminated intravascular coagulation in sepsis.

    PubMed

    Zeerleder, Sacha; Hack, C Erik; Wuillemin, Walter A

    2005-10-01

    Disseminated intravascular coagulation is a frequent complication of sepsis. Coagulation activation, inhibition of fibrinolysis, and consumption of coagulation inhibitors lead to a procoagulant state resulting in inadequate fibrin removal and fibrin deposition in the microvasculature. As a consequence, microvascular thrombosis contributes to promotion of organ dysfunction. Recently, three randomized, double-blind, placebo-controlled trials investigated the efficacy of antithrombin, activated protein C (APC), and tissue factor pathway inhibitor, respectively, in sepsis patients. A significant reduction in mortality was demonstrated in the APC trial. In this article, we first discuss the physiology of coagulation and fibrinolysis activation. Then, the pathophysiology of coagulation activation, consumption of coagulation inhibitors, and the inhibition of fibrinolysis leading to a procoagulant state are described in more detail. Moreover, therapeutic concepts as well as the three randomized, double-blind, placebo-controlled studies are discussed.

  3. Obstetrical disseminated intravascular coagulation score.

    PubMed

    Kobayashi, Takao

    2014-06-01

    Obstetrical disseminated intravascular coagulation (DIC) is usually a very acute, serious complication of pregnancy. The obstetrical DIC score helps with making a prompt diagnosis and starting treatment early. This DIC score, in which higher scores are given for clinical parameters rather than for laboratory parameters, has three components: (i) the underlying diseases; (ii) the clinical symptoms; and (iii) the laboratory findings (coagulation tests). It is justifiably appropriate to initiate therapy for DIC when the obstetrical DIC score reaches 8 points or more before obtaining the results of coagulation tests. Improvement of blood coagulation tests and clinical symptoms are essential to the efficacy evaluation for treatment after a diagnosis of obstetrical DIC. Therefore, the efficacy evaluation criteria for obstetrical DIC are also defined to enable follow-up of the clinical efficacy of DIC therapy.

  4. Treatment of Disseminated Intravascular Coagulation.

    PubMed

    Makruasi, Nisa

    2015-11-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic activation of blood coagulation, generation of thrombin, and leading to disturbance of the microvasculature. In this article, definition and diagnostic criteria of DIC depend on the International Society of Thrombosis and Haemostasis (ISTH). There is no gold standard for diagnosis of DIC, only low quality evidence is used in general practice. Many diagnostic tests and repeated measurement are required. For the treatment of DIC, there is no good quality evidence. The most important treatment for DIC is the specific treatment of the conditions associated DIC. Platelets and/or plasma transfusion may be also necessary if indicated. Nevertheless, there is no gold standard for diagnosis and treatment of DIC, we use only low quality evidence in general practice.

  5. Pulmonary intravascular lipid in neonatal necropsy specimens.

    PubMed

    Puntis, J W; Rushton, D I

    1991-01-01

    The lungs of 482 liveborn infants were examined at necropsy for the presence of intravascular lipid. Forty one patients had received parenteral feeding (including lipid emulsion in 30), and 441 had died before starting feeds or had received enteral feeds alone. Tissue was processed into wax and then stained with Sudan black; intravascular lipid was found in 15 of 30 infants who had received intravenous fat (Intralipid), but in no others. Those patients with positive lipid staining had received significantly more fat during parenteral nutrition than those in whom intravascular lipid was not found but the two groups were otherwise clinically indistinguishable. Using this staining technique intravascular lipid can be shown relatively often, although only in patients who have received intravenous lipid emulsion. The location of fat, predominantly in small pulmonary capillaries, and the absence of lipid emboli in other organs, suggests that lipid coalescence takes place before death and is not a postmortem artefact. The clinical relevance remains uncertain. PMID:1899990

  6. Pulmonary intravascular lipid in neonatal necropsy specimens.

    PubMed

    Puntis, J W; Rushton, D I

    1991-01-01

    The lungs of 482 liveborn infants were examined at necropsy for the presence of intravascular lipid. Forty one patients had received parenteral feeding (including lipid emulsion in 30), and 441 had died before starting feeds or had received enteral feeds alone. Tissue was processed into wax and then stained with Sudan black; intravascular lipid was found in 15 of 30 infants who had received intravenous fat (Intralipid), but in no others. Those patients with positive lipid staining had received significantly more fat during parenteral nutrition than those in whom intravascular lipid was not found but the two groups were otherwise clinically indistinguishable. Using this staining technique intravascular lipid can be shown relatively often, although only in patients who have received intravenous lipid emulsion. The location of fat, predominantly in small pulmonary capillaries, and the absence of lipid emboli in other organs, suggests that lipid coalescence takes place before death and is not a postmortem artefact. The clinical relevance remains uncertain.

  7. Performance tuned radioisotope thermophotovoltaic space power system

    NASA Astrophysics Data System (ADS)

    Horne, W. E.; Morgan, M. D.; Saban, S. B.

    1998-01-01

    The trend in space exploration is to use many small, low-cost, special-purpose satellites instead of the large, high-cost, multipurpose satellites used in the past. As a result of this new trend, there is a need for lightweight, efficient, and compact radioisotope fueled electrical power generators. This paper presents an improved design for a radioisotope thermophotovoltaic (RTPV) space power system in the 10 W to 20 W class which promises up to 37.6 watts at 30.1% efficiency and 25 W/kg specific power. The RTPV power system concept has been studied and compared to radioisotope thermoelectric generators (RTG) radioisotope, Stirling generators and alkali metal thermal electric conversion (AMTEC) generators (Schock, 1995). The studies indicate that RTPV has the potential to be the lightest weight, most efficient and most reliable of the three concepts. However, in spite of the efficiency and light weight, the size of the thermal radiator required to eliminate excess heat from the PV cells and the lack of actual system operational performance data are perceived as obstacles to RTPV acceptance for space applications. Between 1994 and 1997 EDTEK optimized the key converter components for an RTPV generator under Department of Energy (DOE) funding administered via subcontracts to Orbital Sciences Corporation (OSC) and EG&G Mound Applied Technologies Laboratory (Horne, 1995). The optimized components included a resonant micromesh infrared bandpass filter, low-bandgap GaSb PV cells and cell arrays. Parametric data from these components were supplied to OSC who developed and analyzed the performance of 100 W, 20 W, and 10 W RTPV generators. These designs are described in references (Schock 1994, 1995 and 1996). Since the performance of each class of supply was roughly equivalent and simply scaled with size, this paper will consider the OSC 20 W design as a baseline. The baseline 20-W RTPV design was developed by Schock, et al of OSC and has been presented elsewhere. The

  8. High efficiency radioisotope thermophotovoltaic prototype generator

    NASA Technical Reports Server (NTRS)

    Avery, James E.; Samaras, John E.; Fraas, Lewis M.; Ewell, Richard

    1995-01-01

    A radioisotope thermophotovoltaic generator space power system (RTPV) is lightweight, low-cost alternative to the present radioisotope thermoelectric generator system (RTG). The fabrication of such an RTPV generator has recently become feasible as the result of the invention of the GaSb infrared sensitive photovoltaic cell. Herein, we present the results of a parametric study of emitters and optical filters in conjuction with existing data on gallium antimonide cells. We compare a polished tungsten emitter with an Erbia selective emitter for use in combination with a simple dielectric filter and a gallium antimonide cell array. We find that the polished tungsten emitter is by itself a very selective emitter with low emissivity beyond 4 microns. Given a gallium antimonide cell and a tungsten emitter, a simple dielectric filter can be designed to transmit radiant energy below 1.7 microns and to reflect radiant energy between 1.7 and 4 microns back to the emitter. Because of the low long wavelength emissivity associated with the polished tungsten emitter, this simple dielectric filter then yields very respectable system performance. Also as a result of the longer wavelength fall-off in the tungsten emissivity curve, the radiation energy peak for a polished tungsten emitter operating at 1300 K shifts to shorter wavelengths relative to the blackbody spectrum so that the radiated energy peak falls right at the gallium antimonide cell bandedge. The result is that the response of the gallium antimonide cell is well matched to a polished tungsten emitter. We propose, therefore, to fabricate an operating prototype of a near term radioisotope thermophotovoltaic generator design consisting of a polished tungsten emitter, standard gallium antimonide cells, and a near-term dielectric filter. The Jet Propulsion Laboratory will design and build the thermal cavity, and JX Crystals will fabricate the gallium antimonide cells, dielectric filters, and resultant receiver panels. With

  9. High efficiency radioisotope thermophotovoltaic prototype generator

    NASA Astrophysics Data System (ADS)

    Avery, James E.; Samaras, John E.; Fraas, Lewis M.; Ewell, Richard

    1995-10-01

    A radioisotope thermophotovoltaic generator space power system (RTPV) is lightweight, low-cost alternative to the present radioisotope thermoelectric generator system (RTG). The fabrication of such an RTPV generator has recently become feasible as the result of the invention of the GaSb infrared sensitive photovoltaic cell. Herein, we present the results of a parametric study of emitters and optical filters in conjuction with existing data on gallium antimonide cells. We compare a polished tungsten emitter with an Erbia selective emitter for use in combination with a simple dielectric filter and a gallium antimonide cell array. We find that the polished tungsten emitter is by itself a very selective emitter with low emissivity beyond 4 microns. Given a gallium antimonide cell and a tungsten emitter, a simple dielectric filter can be designed to transmit radiant energy below 1.7 microns and to reflect radiant energy between 1.7 and 4 microns back to the emitter. Because of the low long wavelength emissivity associated with the polished tungsten emitter, this simple dielectric filter then yields very respectable system performance. Also as a result of the longer wavelength fall-off in the tungsten emissivity curve, the radiation energy peak for a polished tungsten emitter operating at 1300 K shifts to shorter wavelengths relative to the blackbody spectrum so that the radiated energy peak falls right at the gallium antimonide cell bandedge. The result is that the response of the gallium antimonide cell is well matched to a polished tungsten emitter. We propose, therefore, to fabricate an operating prototype of a near term radioisotope thermophotovoltaic generator design consisting of a polished tungsten emitter, standard gallium antimonide cells, and a near-term dielectric filter. The Jet Propulsion Laboratory will design and build the thermal cavity, and JX Crystals will fabricate the gallium antimonide cells, dielectric filters, and resultant receiver panels. With

  10. Quantitative blood speed imaging with intravascular ultrasound.

    PubMed

    Crowe, J R; O'Donnell, M

    2001-03-01

    Previously, we presented a method of real-time arterial color flow imaging using an intravascular ultrasound (IVUS) imaging system, where real-time RF A-scans were processed with an FIR (finite-impulse response) filter bank to estimate relative blood speed. Although qualitative flow measurements are clinically valuable, realizing the full potential of blood flow imaging requires quantitative flow speed and volume measurements in real time. Unfortunately, the rate of RF echo-to-echo decorrelation is not directly related to scatterer speed in a side-looking IVUS system because the elevational extent of the imaging slice varies with range. Consequently, flow imaging methods using any type of decorrelation processing to estimate blood speed without accounting for spatial variation of the radiation pattern will have estimation errors that prohibit accurate comparison of speed estimates from different depths. The FIR filter bank approach measures the rate of change of the ultrasound signal by estimating the slow-time spectrum of RF echoes. A filter bank of M bandpass filters is applied in parallel to estimate M components of the slow-time DFT (discrete Fourier transform). The relationship between the slow-time spectrum, aperture diffraction pattern, and scatterer speed is derived for a simplified target. Because the ultimate goal of this work is to make quantitative speed measurements, we present a method to map slow time spectral characteristics to a quantitative estimate. Results of the speed estimator are shown for a simulated circumferential catheter array insonifying blood moving uniformly past the array (i.e., plug flow) and blood moving with a parabolic profile (i.e., laminar flow). PMID:11370361

  11. [A method for studying intravascular platelet aggregation in vitro].

    PubMed

    Ikonnikova, E I; Chernousova, L A; Moshkina, I R

    1999-06-01

    A simple available method for evaluating intravascular platelet aggregation is proposed. It consists in graphic recording of disaggregation of platelet-rich citrate plasma, which indicates the degree of intravascular aggregation. Intravascular aggregation is notably increased in coronary patients and negligible in normal subjects. The method may be used for the diagnosis of diseases with a high thrombogenic risk.

  12. How to Handle Radioisotopes Safely.

    ERIC Educational Resources Information Center

    Sulcoski, John W.

    This booklet is one in a series of instructional aids designed for use by elementary and secondary school science teachers. The various units and forms of radioactive materials used by teachers are first considered. Then, the quantities of radioisotopes that a person may possess without a license from the Atomic Energy Commission (AEC) are…

  13. An in-cell alpha detection system for radioisotope component assembly operations

    SciTech Connect

    Carteret, B.A. ); Goles, R.W. )

    1991-09-01

    A remotely operated alpha detection system is being developed for use at the Radioisotope Power Systems Facility at the US Department of Energy's Hanford Site. It will be used in hot cells being constructed to assemble components of Radioisotope Thermoelectric Generators for space power applications. The in-cell detection equipment will survey radiological swipe samples to determine smearable surface contamination levels on radioisotope fuel, fueled components, and hot-cell work areas. This system is potentially adaptable to other hot cell and glovebox applications where radiation dose rates and contamination levels are expected to be low. 2 figs.

  14. Efficient Radioisotope Energy Transfer by Gold Nanoclusters for Molecular Imaging.

    PubMed

    Volotskova, Olga; Sun, Conroy; Stafford, Jason H; Koh, Ai Leen; Ma, Xiaowei; Cheng, Zhen; Cui, Bianxiao; Pratx, Guillem; Xing, Lei

    2015-08-26

    Beta-emitting isotopes Fluorine-18 and Yttrium-90 are tested for their potential to stimulate gold nanoclusters conjugated with blood serum proteins (AuNCs). AuNCs excited by either medical radioisotope are found to be highly effective ionizing radiation energy transfer mediators, suitable for in vivo optical imaging. AuNCs synthesized with protein templates convert beta-decaying radioisotope energy into tissue-penetrating optical signals between 620 and 800 nm. Optical signals are not detected from AuNCs incubated with Technetium-99m, a pure gamma emitter that is used as a control. Optical emission from AuNCs is not proportional to Cerenkov radiation, indicating that the energy transfer between the radionuclide and AuNC is only partially mediated by Cerenkov photons. A direct Coulombic interaction is proposed as a novel and significant mechanism of energy transfer between decaying radionuclides and AuNCs.

  15. Utility of intravascular ultrasound in peripheral interventions.

    PubMed Central

    White, R A; Donayre, C E; Kopchok, G E; Walot, I; Mehringer, C M

    1997-01-01

    Endovascular imaging techniques encompass a variety of methods, including angiography, computed tomography, magnetic resonance imaging, angioscopy, and intravascular ultrasound. Each method provides unique information regarding the continuity of vascular structures and the morphology and distribution of lesions. Although arteriography has been the "gold standard" for imaging arterial anatomy, recent data have confirmed that even sophisticated arteriographic imaging substantially underestimates the degree of residual lesions, and that future observations and end-points for treatment will most likely be determined by data accumulated by computed tomography, magnetic resonance imaging, angioscopy, and intravascular ultrasound. Successful therapeutic applications of endovascular devices have developed because of improved patient selection using computed tomography, spiral computed tomography, magnetic resonance imaging, and computerized high-resolution angiography. Procedural success has been enhanced by improved mobile cinefluoroscopy, angioscopy, intraluminal ultrasound monitoring of angioplasty procedures, and the use of intravascular ultrasound for stent and stent-graft sizing and deployment. Newly developed methods and low-profile delivery systems enabling deployment and fixation of vascular prostheses by an endoluminal approach have heightened the interest of many interventionalists, particularly surgeons, in the use of endovascular surgical techniques. The evolution of this method promises to add a new dimension to the treatment of vascular lesions and relies heavily on the incorporation of miniaturized imaging systems, such as intravascular ultrasound, as a means to provide precise placement of devices. Images PMID:9068136

  16. [Possibilities for cardiac defibrillation using intravascular electrodes].

    PubMed

    Amosov, G G; Tolpekin, V E; Gasanov, E K; Fomichev, D I

    1987-05-01

    The efficiency of electric defibrillation of the heart was assessed in 17 experiments where the position of action electrodes varied. It is suggested that intravascular application of one electrode plus extravascular application of the other gives the optimum effect. The duration of unassisted reversible fibrillation averaged 3 minutes.

  17. Performance tuned radioisotope thermophotovoltaic space power system

    SciTech Connect

    Horne, W.E.; Morgan, M.D.; Saban, S.B.

    1998-01-01

    The trend in space exploration is to use many small, low-cost, special-purpose satellites instead of the large, high-cost, multipurpose satellites used in the past. As a result of this new trend, there is a need for lightweight, efficient, and compact radioisotope fueled electrical power generators. This paper presents an improved design for a radioisotope thermophotovoltaic (RTPV) space power system in the 10 W to 20 W class which promises up to 37.6 watts at 30.1{percent} efficiency and 25 W/kg specific power. The RTPV power system concept has been studied and compared to radioisotope thermoelectric generators (RTG) radioisotope, Stirling generators and alkali metal thermal electric conversion (AMTEC) generators (Schock, 1995). The studies indicate that RTPV has the potential to be the lightest weight, most efficient and most reliable of the three concepts. However, in spite of the efficiency and light weight, the size of the thermal radiator required to eliminate excess heat from the PV cells and the lack of actual system operational performance data are perceived as obstacles to RTPV acceptance for space applications. Between 1994 and 1997 EDTEK optimized the key converter components for an RTPV generator under Department of Energy (DOE) funding administered via subcontracts to Orbital Sciences Corporation (OSC) and EG&G Mound Applied Technologies Laboratory (Horne, 1995). The optimized components included a resonant micromesh infrared bandpass filter, low-bandgap GaSb PV cells and cell arrays. Parametric data from these components were supplied to OSC who developed and analyzed the performance of 100 W, 20 W, and 10 W RTPV generators. These designs are described in references (Schock 1994, 1995 and 1996). Since the performance of each class of supply was roughly equivalent and simply scaled with size, this paper will consider the OSC 20 W design as a baseline. The baseline 20-W RTPV design was developed by Schock, et al of OSC and has been presented elsewhere

  18. HFIR-produced medical radioisotopes

    SciTech Connect

    Mirzadeh, S.; Knapp, F.F. Jr.; Beets, A.L.; Alexander, C.W.

    1997-12-01

    We have experimentally determined the yields of a number of medical radioisotopes produced in the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR) Hydraulic Tube (HT) facility. The HT facility is located in the very high flux region in the flux trap of the reactor, providing on-line access capability while the reactor is operating. The HT facility consists of nine vertically stacked capsules centered just adjacent to the core horizontal midplane. HFIR operates at a nominal power level of 85 MW. The capabilities of the HFIR-HT facilities offer increased efficiency, greater availability, and optimization of radioisotope production, and, as a result, the conservation of rare or expensive target isotopes.

  19. Disposal of plasma heme in normal man and patients with intravascular hemolysis

    PubMed Central

    Sears, David A.

    1970-01-01

    The clearance of plasma protein-bound heme, its sites of removal, and the reutilization of hemeiron were studied by radioisotopic techniques in normal human subjects and in patients with intravascular hemolysis. In normal subjects, injected heme-59Fe was bound immediately by albumin and the β1-globulin, hemopexin. Its clearance from the plasma was descr bed by a single exponential equation, and the half-life in plasma was 7-8 hr. Removal was largely by the liver. Iron reutilization began promptly, and half the injected heme-iron was incorporated into circulating red cells within one cell life-span. In patients with intravascular hemolysis, hemopexin was depleted, and injected heme was bound solely to albumin. Plasma clearance was described by a double exponential equation of the form: y = Ae-k1t + Be-k2t. The half-lives of the two components averaged 3.9 and 22.2 hr, respectively. Removal was by the liver in at least some of the patients, and iron reutilization was variable, depending on the state of body iron stores. When hemopex'n was depleted in a normal subject by repeated heme injection, clearance mimicked that observed in the patients. Images PMID:4188269

  20. Disposal of plasma heme in normal man and patients with intravascular hemolysis.

    PubMed

    Sears, D A

    1970-01-01

    The clearance of plasma protein-bound heme, its sites of removal, and the reutilization of hemeiron were studied by radioisotopic techniques in normal human subjects and in patients with intravascular hemolysis. In normal subjects, injected heme-(59)Fe was bound immediately by albumin and the beta(1)-globulin, hemopexin. Its clearance from the plasma was descr bed by a single exponential equation, and the half-life in plasma was 7-8 hr. Removal was largely by the liver. Iron reutilization began promptly, and half the injected heme-iron was incorporated into circulating red cells within one cell life-span. In patients with intravascular hemolysis, hemopexin was depleted, and injected heme was bound solely to albumin. Plasma clearance was described by a double exponential equation of the form: y = Ae(-k1t) + Be(-k2t). The half-lives of the two components averaged 3.9 and 22.2 hr, respectively. Removal was by the liver in at least some of the patients, and iron reutilization was variable, depending on the state of body iron stores. When hemopex'n was depleted in a normal subject by repeated heme injection, clearance mimicked that observed in the patients.

  1. An Overview and Status of NASA's Radioisotope Power Conversion Technology NRA

    NASA Technical Reports Server (NTRS)

    Anderson, David J.; Wong, Wayne A.; Tuttle, Karen L.

    2005-01-01

    NASA's Advanced Radioisotope Power Systems (RPS) development program is developing next generation radioisotope power conversion technologies that will enable future missions that have requirements that can not be met by either photovoltaic systems or by current Radioisotope Power System (RPS) technology. The Advanced Power Conversion Research and Technology project of the Advanced RPS development program is funding research and technology activities through the NASA Research Announcement (NRA) 02-OSS-01, "Research Opportunities in Space Science 2002" entitled "Radioisotope Power Conversion Technology" (RPCT), August 13, 2002. The objective of the RPCT NRA is to advance the development of radioisotope power conversion technologies to provide significant improvements over the state-of-practice General Purpose Heat Source/Radioisotope Thermoelectric Generator by providing significantly higher efficiency to reduce the number of radioisotope fuel modules, and increase specific power (watts/kilogram). Other Advanced RPS goals include safety, long-life, reliability, scalability, multi-mission capability, resistance to radiation, and minimal interference with the scientific payload. Ten RPCT NRA contracts were awarded in 2003 in the areas of Brayton, Stirling, thermoelectric (TE), and thermophotovoltaic (TPV) power conversion technologies. This paper will provide an overview of the RPCT NRA, and a brief summary of accomplishments over the first 18 months but focusing on advancements made over the last 6 months.

  2. Estimating the actual dose delivered by intravascular coronary brachytherapy using geometrically correct 3D modeling

    NASA Astrophysics Data System (ADS)

    Wahle, Andreas; Lopez, John J.; Pennington, Edward C.; Meeks, Sanford L.; Braddy, Kathleen C.; Fox, James M.; Brennan, Theresa M. H.; Buatti, John M.; Rossen, James D.; Sonka, Milan

    2003-05-01

    Intravascular brachytherapy has shown to reduce re-occurrence of in-stent restenosis in coronary arteries. For beta radiation, application time is determined from source activity and the angiographically estimated vessel diameter. Conventionally used dosing models assume a straight vessel with the catheter centered and a constant-diameter circular cross section. Aim of this study was to compare the actual dose delivered during in-vivo intravascular brachytherapy with the target range determined from the patient's prescribed dose. Furthermore, differences in dose distribution between a simplified tubular model (STM) and a geometrically correct 3-D model (GCM) obtained from fusion between biplane angiography and intravascular ultrasound were quantified. The tissue enclosed by the segmented lumen/plaque and media/adventitia borders was simulated using a structured finite-element mesh. The beta-radiation sources were modeled as 3-D objects in their angiographically determined locations. The accumulated dose was estimated using a fixed distance function based on the patient-specific radiation parameters. For visualization, the data was converted to VRML with the accumulated doses represented by color encoding. The statistical comparison between STM and GCM models in 8 patients showed that the STM significantly underestimates the dose delivered and its variability. The analysis revealed substantial deviations from the target dose range in curved vessels.

  3. Intravascular access in pediatric cardiac arrest.

    PubMed

    Brunette, D D; Fischer, R

    1988-11-01

    All cases of patients aged less than 48 months who presented in cardiac arrest to the Hennepin County Medical Center's emergency department (ED) during the years 1984 to 1986 were reviewed retrospectively. The ED record, initial and subsequent chest radiographs, hospital charts, and autopsy reports were analyzed. A total of 33 cases were reviewed. The average patient age was 5 months. The average time needed to establish intravascular access was 7.9 +/- 4.2 minutes. Success rates were 77% for central venous catheterization, 81% for surgical vein cutdown, 83% for intraosseous infusion, and 17% for percutaneous peripheral catheterization. Percutaneous peripheral catheterization, when successful, and bone marrow needle placement were the fastest methods of obtaining intravascular access. There were no major immediate complications, and delayed complications were minimal. Attempts at peripheral intravenous catheter placement should be brief, with rapid progression to intraosseous infusion if peripheral attempts are not successful. PMID:3178949

  4. [Intravascular lymphoma: Report of one case].

    PubMed

    Young, Pablo; Massa, María; Finn, Bárbara C; Fleire, Gonzalo; Stemmelin, Germán R; Ruades, Amanda; Sutovsky, Daniel; Casas, José G; Dezanzo, Pablo; Vigovich, Félix; Bruetman, Julio E

    2015-08-01

    Intravascular lymphoma is a rare subtype of extranodal diffuse large B-cell lymphoma characterized by clonal proliferation of lymphocytes inside of small and medium caliber vessels. Its incidence is estimated at one case per million. The clinical picture is very variable, but frequently has skin and central nervous system involvement. It is diagnosed by demonstrating pathological blood vessel infiltration by lymphoma cells. We report a 44 years old male presenting with fever, malaise and erythematous lesions in the abdominal wall. An abdominal wall biopsy showed dilated vascular vessels with atypical cells in their lumen, compatible with large B-cell intravascular lymphoma. He was treated with rituximab, cyclophosphamide, adriamycin, vincristine and prednisone and an autologous hematopoietic stem cell transplantation, achieving a complete remission that has lasted two years. PMID:26436939

  5. Techniques for Intravascular Foreign Body Retrieval

    SciTech Connect

    Woodhouse, Joe B.; Uberoi, Raman

    2013-08-01

    As endovascular therapies increase in frequency, the incidence of lost or embolized foreign bodies is increasing. The presence of an intravascular foreign body (IFB) is well recognized to have the potential to cause serious complications. IFB can embolize and impact critical sites such as the heart, with subsequent significant morbidity or mortality. Intravascular foreign bodies most commonly result from embolized central line fragments, but they can originate from many sources, both iatrogenic and noniatrogenic. The percutaneous approach in removing an IFB is widely perceived as the best way to retrieve endovascular foreign bodies. This minimally invasive approach has a high success rate with a low associated morbidity, and it avoids the complications related to open surgical approaches. We examined the characteristics, causes, and incidence of endovascular embolizations and reviewed the various described techniques that have been used to facilitate subsequent explantation of such materials.

  6. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1985

    SciTech Connect

    Baker, D.A.

    1986-08-01

    This document describes radioisotope distribution from DOE facilities to private firms including foreign and other DOE facilities. The information is divided into five sections: (1) isotope suppliers, facility contacts, and isotopes or services supplied; (2) customers, suppliers, and isotopes purchased; (3) isotopes purchased cross-referenced with customer numbers; (4) geographic locations of radioisotope customers; and (5) radioisotope sales and transfer - FY 1985.

  7. [Disseminated intravascular coagulation in solid tumours].

    PubMed

    Ferrand, François Régis; Garcia-Hejl, Carine; Moussaid, Yassine; Schernberg, Antoine; Bidard, François-Clément; Pavic, Michel; Khenifer, Safia; Stoclin, Annabelle

    2014-06-01

    Disseminated intravascular coagulation (DIC) is a complex abnormality of hemostasis with dramatic consequences and long described as associated with tumors. Yet the diagnosis and management of paraneoplastic DIC are poorly defined. The purpose of this paper is to review DIC associated with solid tumors, at the pathophysiological and therapeutic levels in particular. We also report data from a recent retrospective series of patients with DIC in the context of a solid tumor, to illustrate the epidemiological, clinical and prognostic.

  8. Percutaneous Retrieval of Chronic Intravascular Foreign Bodies

    SciTech Connect

    Savage, Clare; Ozkan, Orhan S.; Walser, Eric M.; Wang Dongfang; Zwischenberger, Joseph B.

    2003-09-15

    To evaluate the feasibility of intravascular retrieval of chronic foreign bodies, we retrospectively reviewed an 8 year experience (1993-2001) of percutaneous retrieval of chronically retained intravascular foreign bodies (n = 6). In 6 of 6 cases (4 catheter fragments, 2 guidewires), 5-90 days elapsed before retrieval via the femoral or internal jugular vein. Under fluoroscopy, we determined the foreign body's course, position and size. A guidewire was advanced through a multipurpose catheter to the foreign body. The multipurpose catheter was replaced with a gooseneck snare catheter and the snare advanced to grasp and remove the foreign body. Percutaneous retrieval was successful in all 6 cases. One patient experienced mild hemoptysis, which resolved within 24 hr of observation. No patient experienced long-term sequelae. Given the potential life-threatening complications from intravascular foreign bodies and the low complication rate from percutaneous retrieval, we recommend extraction of the foreign body even if it is asymptomatic in the chronic setting (> 24 hr)

  9. Diagnosis and treatment of disseminated intravascular coagulation.

    PubMed

    Levi, M

    2014-06-01

    Disseminated intravascular coagulation (DIC) is a condition in which systemic activation of coagulation without a specific localization occurs, resulting in extensive formation of intravascular fibrin, particularly in small and midsize vessels. Disseminated intravascular coagulation may lead to several altered coagulation parameters, including a low platelet count, abnormal global clotting assays, low levels of physiological anticoagulant proteases, or increased fibrin degradation products. Also, more complex assays for activation of coagulation factors or pathways may indicate involvement of these molecules in DIC. None of these tests alone, however, can accurately ascertain or rebuff a diagnosis of DIC. Nonetheless, a combination of readily available routine assays may be instrumental in establishing a diagnosis of DIC and can also be useful to point to a subset of patients with DIC that may need definite, often costly, interventions in the hemostatic system. Current insights on relevant etiological pathways that may contribute to the occurrence of DIC have led to innovative therapeutic and adjunctive approaches to patient with DIC. Management options directed at the amelioration of hemostatic activation may tentatively be indicated and were found to be advantageous in experimental and clinical investigations. These treatments encompass elimination of tissue factor-mediated thrombin generation or restitution of normal anticoagulant function.

  10. Accidental radioisotope burns - Management of late sequelae.

    PubMed

    Varghese, Bipin T; Thomas, Shaji; Nair, Balakrishnan; Mathew, P C; Sebastian, Paul

    2010-09-01

    Accidental radioisotope burns are rare. The major components of radiation injury are burns, interstitial pneumonitis, acute bone marrow suppression, acute renal failure and adult respiratory distress syndrome. Radiation burns, though localized in distribution, have systemic effects, and can be extremely difficult to heal, even after multiple surgeries. In a 25 year old male who sustained such trauma by accidental industrial exposure to Iridium192 the early presentation involved recurrent haematemesis, pancytopenia and bone marrow suppression. After three weeks he developed burns in contact areas in the left hand, left side of the chest, abdomen and right inguinal region. All except the inguinal wound healed spontaneously but the former became a non-healing ulcer. Pancytopenia and bone marrow depression followed. He was treated with morphine and NSAIDs, epidural buprinorphine and bupivicaine for pain relief, steroids, antibiotics followed by wound excision and reconstruction with tensor fascia lata(TFL) flap. Patient had breakdown of abdominal scar later and it was excised with 0.5 cm margins up to the underlying muscle and the wound was covered by a latissimis dorsi flap. Further scar break down and recurrent ulcers occurred at different sites including left wrist, left thumb and right heel in the next two years which needed multiple surgical interventions. PMID:21321664

  11. Detectors for medical radioisotope imaging: demands and perspectives

    NASA Astrophysics Data System (ADS)

    Lopes, M. I.; Chepel, V.

    2004-10-01

    Radioisotope imaging is used to obtain information on biochemical processes in living organisms, being a tool of increasing importance for medical diagnosis. The improvement and expansion of these techniques depend on the progress attained in several areas, such as radionuclide production, radiopharmaceuticals, radiation detectors and image reconstruction algorithms. This review paper will be concerned only with the detector technology. We will review in general terms the present status of medical radioisotope imaging instrumentation with the emphasis put on the developments of high-resolution gamma cameras and PET detector systems for scinti-mammography and animal imaging. The present trend to combine two or more modalities in a single machine in order to obtain complementary information will also be considered.

  12. Power from Radioisotopes, Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Corliss, William R.; Mead, Robert L.

    This 1971 revision deals with radioisotopes and their use in power generators. Early developments and applications for the Systems for Nuclear Auxiliary Power (SNAP) and Radioisotope Thermoelectric Generators (RTGs) are reviewed. Present uses in space and on earth are included. Uses in space are as power sources in various satellites and space…

  13. Radioisotope penogram in diagnosis of vasculogenic impotence

    SciTech Connect

    Fanous, H.N.; Jevtich, M.J.; Chen, D.C.; Edson, M.

    1982-11-01

    A radioisotope technique to estimate penile blood flow is described. The radioisotope penogram is noninvasive and gives a dynamic evaluation of the arterial supply, venous drainage, and blood flow in the corporeal bodies. The penogram is a valuable adjunct in evaluation of patients with vasculogenic impotence.

  14. Hypothesis: Disseminated Intravascular Inflammation as the Inflammatory Counterpart to Disseminated Intravascular Coagulation

    NASA Astrophysics Data System (ADS)

    Bull, Brian S.; Bull, Maureen H.

    1994-08-01

    We have identified a leukocyte activation syndrome that is occasionally associated with the transfusion of intraoperatively recovered erythrocytes. This syndrome appears to result from intravascular damage caused by leukocytes activated during the erythrocyte salvage process. We hypothesize that this syndrome is part of a larger disease grouping: disseminated intravascular inflammation (DII). DII is the analog of the coagulation disorder disseminated intravascular coagulation. In disseminated intravascular coagulation, the organ damage results from uncontrolled activation of the clotting pathway; in DII the damage is caused by leukocytes that have become activated by direct contact with bacteria or in rare instances-such as erythrocyte salvage-in the absence of bacteria and bacterial products. Recent studies of the hazards associated with intraoperative blood salvage indicate that activation of leukocytes can be achieved by exposure to activated platelets alone. If such activated leukocytes are reinfused along with the washed erythrocytes, widespread organ damage may result. The lung is the organ most severely affected by activated leukocytes. Adult respiratory distress syndrome is one outcome. It is likely that DII is a presently unrecognized pathophysiological process that complicates a variety of primary disease states and increases their lethality.

  15. Radioisotope Power: A Key Technology for Deep Space Explorations

    NASA Technical Reports Server (NTRS)

    Schmidt, George R.; Sutliff, Thomas J.; Duddzinski, Leonard

    2009-01-01

    A Radioisotope Power System (RPS) generates power by converting the heat released from the nuclear decay of radioactive isotopes, such as Plutonium-238 (Pu-238), into electricity. First used in space by the U.S. in 1961, these devices have enabled some of the most challenging and exciting space missions in history, including the Pioneer and Voyager probes to the outer solar system; the Apollo lunar surface experiments; the Viking landers; the Ulysses polar orbital mission about the Sun; the Galileo mission to Jupiter; the Cassini mission orbiting Saturn; and the recently launched New Horizons mission to Pluto. Radioisotopes have also served as a versatile heat source for moderating equipment thermal environments on these and many other missions, including the Mars exploration rovers, Spirit and Opportunity. The key advantage of RPS is its ability to operate continuously, independent of orientation and distance relative to the Sun. Radioisotope systems are long-lived, rugged, compact, highly reliable, and relatively insensitive to radiation and other environmental effects. As such, they are ideally suited for missions involving long-lived, autonomous operations in the extreme conditions of space and other planetary bodies. This paper reviews the history of RPS for the U.S. space program. It also describes current development of a new Stirling cycle-based generator that will greatly expand the application of nuclear-powered missions in the future.

  16. Radioisotope Power: A Key Technology for Deep Space Exploration

    NASA Technical Reports Server (NTRS)

    Schmidt, George; Sutliff, Tom; Dudzinski, Leonard

    2008-01-01

    A Radioisotope Power System (RPS) generates power by converting the heat released from the nuclear decay of radioactive isotopes, such as Plutonium-238 (Pu-238), into electricity. First used in space by the U.S. in 1961, these devices have enabled some of the most challenging and exciting space missions in history, including the Pioneer and Voyager probes to the outer solar system; the Apollo lunar surface experiments; the Viking landers; the Ulysses polar orbital mission about the Sun; the Galileo mission to Jupiter; the Cassini mission orbiting Saturn; and the recently launched New Horizons mission to Pluto. Radioisotopes have also served as a versatile heat source for moderating equipment thermal environments on these and many other missions, including the Mars exploration rovers, Spirit and Opportunity. The key advantage of RPS is its ability to operate continuously, independent of orientation and distance relative to the Sun. Radioisotope systems are long-lived, rugged, compact, highly reliable, and relatively insensitive to radiation and other environmental effects. As such, they are ideally suited for missions involving long-lived, autonomous operations in the extreme conditions of space and other planetary bodies. This paper reviews the history of RPS for the U.S. space program. It also describes current development of a new Stirling cycle-based generator that will greatly expand the application of nuclear-powered missions in the future.

  17. Multi-Frequency Intravascular Ultrasound (IVUS) Imaging

    PubMed Central

    Ma, Teng; Yu, Mingyue; Chen, Zeyu; Fei, Chunlong; Shung, K. Kirk; Zhou, Qifa

    2015-01-01

    Acute coronary syndrome (ACS) is frequently associated with the sudden rupture of a vulnerable atherosclerotic plaque within the coronary artery. Several unique physiological features, including a thin fibrous cap accompanied by a necrotic lipid core, are the targeted indicators for identifying the vulnerable plaques. Intravascular ultrasound (IVUS), a catheter-based imaging technology, has been routinely performed in clinics for more than 20 years to describe the morphology of the coronary artery and guide percutaneous coronary interventions. However, conventional IVUS cannot facilitate the risk assessment of ACS because of its intrinsic limitations, such as insufficient resolution. Renovation of the IVUS technology is essentially needed to overcome the limitations and enhance the coronary artery characterization. In this paper, a multi-frequency intravascular ultrasound (IVUS) imaging system was developed by incorporating a higher frequency IVUS transducer (80 to 150 MHz) with the conventional IVUS (30–50 MHz) system. The newly developed system maintains the advantage of deeply penetrating imaging with the conventional IVUS, while offering an improved higher resolution image with IVUS at a higher frequency. The prototyped multi-frequency catheter has a clinically compatible size of 0.95 mm and a favorable capability of automated image co-registration. In vitro human coronary artery imaging has demonstrated the feasibility and superiority of the multi-frequency IVUS imaging system to deliver a more comprehensive visualization of the coronary artery. This ultrasonic-only intravascular imaging technique, based on a moderate refinement of the conventional IVUS system, is not only cost-effective from the perspective of manufacturing and clinical practice, but also holds the promise of future translation into clinical benefits. PMID:25585394

  18. Disseminated intravascular coagulation in meningococcal sepsis. Case 7.

    PubMed

    Zeerleder, S; Zürcher Zenklusen, R; Hack, C E; Wuillemin, W A

    2003-08-01

    We report on a man (age: 49 years), who died from severe meningococcal sepsis with disseminated intravascular coagulation (DIC), multiple organ dysfunction syndrome and extended skin necrosis. We discuss in detail the pathophysiology of the activation of coagulation and fibrinolysis during sepsis. The article discusses new therapeutic concepts in the treatment of disseminated intravascular coagulation in meningococcal sepsis, too.

  19. Radioisotope scanning in osseous sarcoidosis

    SciTech Connect

    Rohatgi, P.K.

    1980-01-01

    Technetium-99m (/sup 99m/Tc)-labeled pyrophosphate or diphosphonate compounds and gallium-67 citrate (/sup 67/Ga) are two radionuclide scanning agents that are in widespread use in clinical practice. Technetium-99m pyrophosphate is used extensively for bone scanning to detect metastatic bone disease, benign bone tumors, osteomyelitis, benign hypertrophic osteoarthropathy, and Paget's disease. Only two reports describe abnormal /sup 99m/Tc/ pyrophosphate bone scans in four patients with osseous sarcoidosis. Gallium-67 scans are used primarily to localize neoplastic or inflammatory lesions anywhere in the body. In recent years /sup 67/Ga scans have also been used to detect the presence of both pulmonary and extrapulmonary sarcoidosis, but there are no reports describing abnormal uptake of gallium in patients with osseous sarcoidosis. This report describes experience with radioisotope scanning in two patients with osseous sarcoidosis.

  20. NASA's Radioisotope Power Systems - Plans

    NASA Technical Reports Server (NTRS)

    Hamley, John A.; Mccallum, Peter W.; Sandifer, Carl E., II; Sutliff, Thomas J.; Zakrajsek, June F.

    2015-01-01

    NASA's Radioisotope Power Systems (RPS) Program continues to plan and implement content to enable planetary exploration where such systems could be needed, and to prepare more advanced RPS technology for possible infusion into future power systems. The 2014-2015 period saw significant changes, and strong progress. Achievements of near-term objectives have enabled definition of a clear path forward in which payoffs from research investments and other sustaining efforts can be applied. The future implementation path is expected to yield a higher-performing thermoelectric generator design, a more isotope-fuel efficient system concept design, and a robust RPS infrastructure maintained effectively within both NASA and the Department of Energy. This paper describes recent work with an eye towards the future plans that result from these achievements.

  1. Intravascular imaging with a storage phosphor detector

    NASA Astrophysics Data System (ADS)

    Shikhaliev, Polad M.; Petrek, Peter; Matthews, Kenneth L., II; Fritz, Shannon G.; Bujenovic, L. Steven; Xu, Tong

    2010-05-01

    The aim of this study is to develop and test an intravascular positron imaging system based on a storage phosphor detector for imaging and detecting vulnerable plaques of human coronary arteries. The radiotracer F18-FDG accumulates in vulnerable plaques with inflammation of the overlying cap. The vulnerable plaques can, therefore, be imaged by recording positrons emitted from F18-FDG with a detector inserted into the artery. A prototype intravascular detector was constructed based on storage phosphor. The detector uses a flexible storage phosphor tube with 55 mm length, 2 mm diameter and 0.28 mm wall thickness. The intravascular detector is guided into the vessel using x-ray fluoroscopy and the accumulated x-ray signal must be erased prior to positron imaging. For this purpose, a light diffuser, 0.9 mm in diameter and 55 mm in length, was inserted into the detector tube. The light diffuser was connected to a laser source through a 2 m long optical fiber. The diffuser redirected the 0.38 W laser light to the inner surface of the phosphor detector to erase it. A heart phantom with 300 cm3 volume and three coronary arteries with 3.2 mm diameter and with several plaques was constructed. FDG solution with 0.5 µCi cm-3 activity concentration was filled in the heart and coronary arteries. The detector was inserted in a coronary artery and the signal from the plaques and surrounding background activity was recorded for 2 min. Then the phosphor detector was extracted and read out using a storage phosphor reader. The light diffuser erased the signal resulting from fluoroscopic exposure to level below that encountered during positron imaging. Vulnerable plaques with area activities higher than 1.2 nCi mm-2 were visualized by the detector. This activity is a factor of 10-20 lower than that expected in human vulnerable plaques. The detector was able to image the internal surface of the coronary vessels with 50 mm length and 360° circumference. Spatial resolution was 0

  2. Positron autoradiography for intravascular imaging: feasibility evaluation

    NASA Astrophysics Data System (ADS)

    Shikhaliev, Polad M.; Xu, Tong; Ducote, Justin L.; Easwaramoorthy, Balasubramaniam; Mukherjee, Jogeshwar; Molloi, Sabee

    2006-02-01

    Approximately 70% of acute coronary artery disease is caused by unstable (vulnerable) plaques with an inflammation of the overlying cap and high lipid content. A rupturing of the inflamed cap of the plaque results in propagation of the thrombus into the lumen, blockage of the artery and acute ischaemic syndrome or sudden death. Morphological imaging such as angiography or intravascular ultrasound cannot determine inflammation status of the plaque. A radiotracer such as 18F-FDG is accumulated in vulnerable plaques due to higher metabolic activity of the inflamed cap and could be used to detect a vulnerable plaque. However, positron emission tomography (PET) cannot detect the FDG-labelled plaques because of respiratory and heart motions, small size and low activity of the plaques. Plaques can be detected using a miniature particle (positron) detector inserted into the artery. In this work, a new detector concept is investigated for intravascular imaging of the plaques. The detector consists of a storage phosphor tip bound to the end of an intravascular catheter. It can be inserted into an artery, absorb the 18F-FDG positrons from the plaques, withdrawn from the artery and read out. Length and diameter of the storage phosphor tip can be matched to the length and the diameter of the artery. Monte Carlo simulations and experimental evaluations of coronary plaque imaging with the proposed detector were performed. It was shown that the sensitivity of the storage phosphor detector to the positrons of 18F-FDG is sufficient to detect coronary plaques with 1 mm and 2 mm sizes and 590 Bq and 1180 Bq activities in the arteries with 2 mm and 3 mm diameters, respectively. An experimental study was performed using plastic tubes with 2 mm diameter filled with an FDG solution, which simulates blood. FDG spots simulating plaques were placed over the surface of the tube. A phosphor tip was inserted into the tube and imaged the plaques. Exposure time was 1 min in all simulations and

  3. US Department of Energy radioisotope customers with summary of radioisotope shipments, FY 1988

    SciTech Connect

    Van Houten, N.C.

    1989-06-01

    Pacific Northwest Laboratory (PNL) prepared this edition of the radioisotope customer list at the request of the Office of Health and Environmental Research (ER-73), Office of Energy Research, US Department of Energy (DOE). This is the 25th report in a series dating from 1964. This report covers DOE radioisotope sales and distribution activities by its facilities to domestic, foreign and other DOE facilities for FY 1988. The report is divided into five sections: radioisotope suppliers, facility contacts, and radioisotopes or services supplied; a list of customers, suppliers, and radioisotopes purchased; a list of radioisotopes purchased cross-referenced to customer numbers; geographic locations of radioisotope customers; and radioisotope sales and transfers -- FY 1988. Radioisotopes not previously reported in this series of reports were argon-37, arsenic-72, arsenic-73, bismuth-207, gadolinium-151, rhenium-188, rhodium-101, selenium-72, xenon-123 and zirconium-88. The total value of DOE radioisotope sales for FY 1988 was $11.1 million, an increase of 3% from FY 1987.

  4. Modification of hot cells for general purpose heat source assembly at the Radioisotope Power Systems Facility

    NASA Astrophysics Data System (ADS)

    Carteret, B. A.

    1991-09-01

    Eight existing, unused hot cells currently are being modified for use in the Radioisotope Power Systems Facility (RPSF) to assemble Pu-238 fueled heat sources for radioisotope thermoelectric generators (RTGs). Four air atmosphere cells will be used for storage, decanning, and decontamination of the iridium-clad radioisotope fuel. The remaining four argon atmosphere cells will be used to assemble fuel and graphite components for production and packaging of general purpose heat source (GPHS) assembly modules, which provide heat to drive the thermoelectric conversion process in the generators. The hot cells will be equipped to perform remote and glovebox-type operations. They will provide shielding and contamination control measures to reduce worker radiation exposure to levels within current U.S. Department of Energy (DOE) guidelines. Designs emphasize the Westinghouse Hanford Company (Westinghouse Hanford) as low as reasonably achievable (ALARA) radiation protection policy.

  5. Modification of hot cells for general purpose heat source assembly at the radioisotope power systems facility

    NASA Astrophysics Data System (ADS)

    Carteret, Betty A.

    1992-01-01

    Eight existing, unused hot cells currently are being modified for use in the Radioisotope Power Systems Facility (RPSF) to assemble 238Pu-fueled heat sources for Radioisotope Thermoelectric Generators (RTGs). Four air atmosphere cells will be used for storage, decanning, and decontamination of the iridium-clad radioisotope fuel. The remaining four argon atmosphere cells will be used to assemble fuel and graphite components for production and packaging of general purpose heat source (GPHS) assembly modules, which provide heat to drive the thermoelectric conversion process in the generators. The hot cells will be equipped to perform remote and glovebox-type operations. They will provide shielding and contamination control measures to reduce worker radiation exposure to levels within current U.S. Department of Energy (DOE) guidelines. Designs emphasize the Westinghouse Hanford Company (Westinghouse Hanford) as low as reasonably achievable (ALARA) radiation protection policy.

  6. New intravascular flow sensor using fiber optics

    NASA Astrophysics Data System (ADS)

    Stenow, Erik N. D.

    1994-12-01

    A new sensor using fiber optics is suggested for blood flow measurements in small vessels. The sensor principle and a first evaluation on a flow model are presented. The new sensor uses small CO2 gas bubbles as flow markers for optical detection. When the bubbles pass an optical window, light emitted from one fiber is reflected and scattered into another fiber. The sensor has been proven to work in a 3 mm flow model using two 110 micrometers optical fibers and a 100 micrometers steel capillary inserted into a 1 mm guide wire. The evaluation of a sensor archetype shows that the new sensor provides a promising method for intravascular blood flow measurement in small vessels. The linearity for steady state flow is studied in the flow interval 30 - 130 ml/min. comparison with ultrasound Doppler flowmetry was performed for pulsatile flow in the interval 25 - 125 ml/min. with a pulse length between 0.5 and 2 s. The use of intravascular administered CO2 in small volumes is harmless because the gas is rapidly dissolved in whole blood.

  7. Pulsed liquid microjet for intravascular injection

    NASA Astrophysics Data System (ADS)

    Palanker, Daniel V.; Fletcher, Daniel A.; Miller, Jason; Huie, Philip; Marmor, Michael; Blumenkranz, Mark S.

    2002-06-01

    Occlusions of the retinal veins and arteries are associated with common diseases such as hypertension and arteriosclerosis and usually cause severe and irreversible loss of vision. Treatments for these vascular diseases have been unsatisfactory to date in part because of the difficulty of delivering thrombolytic drugs locally within the eye. In this article we describe a pulsed liquid microjet for minimally invasive intra-vascular drug delivery. The microjet is driven by a vapor bubble following an explosive evaporation of saline, produced by a microsecond-long electric discharge in front of the 25 micrometers electrode inside the micronozzle. Expansion of the transient vapor bubble produces a water jet with a diameter equal to the diameter of the nozzle, and with a velocity and duration that are controlled by the pulse energy. We found that fluid could be injected through the wall of a 60-micrometers -diameter artery in choriallantoic membrane using a 15-micrometers diameter liquid jet traveling at more than 60 m/s. Histological analysis of these arteries showed that the width of the perforation is limited to the diameter of the micronozzle, and the penetration depth of the jet is controlled by the discharge energy. The pulsed liquid microjet offers a promising technique for precise and needle-free intravascular delivery of thrombolytic drugs for localized treatment of retinal vascular occlusions.

  8. Fast integrated intravascular photoacoustic/ultrasound catheter

    NASA Astrophysics Data System (ADS)

    Choi, Changhoon; Cho, Seunghee; Kim, Taehoon; Park, Sungjo; Park, Hyoeun; Kim, Jinmoo; Lee, Seunghoon; Kang, Yeonsu; Jang, Kiyuk; Kim, Chulhong

    2016-03-01

    In cardiology, a vulnerable plaque is considered to be a key subject because it is strongly related to atherosclerosis and acute myocardial infarction. Because conventional intravascular imaging devices exhibit several limitations with regard to vulnerable plaque detection, the need for an effective lipid imaging modality has been continuously suggested. Photoacoustic (PA) imaging is a medical imaging technique with a high level of ultrasound (US) resolution and strong optical contrast. In this study, we successfully developed an integrated intravascular photoacoustic/ultrasound (IV-PAUS) imaging system with a catheter diameter of 1.2 mm for lipid-rich atherosclerosis imaging. An Nd:YAG pulsed laser with an excitation wavelength of 1064 nm was utilized. IV-PAUS offers 5-mm depth penetration and axial and lateral PA imaging resolutions of 94 μm and 203 μm, respectively, as determined by imaging a 6-μm carbon fiber. We initially obtained 3-dimensional (3D) co-registered PA/US images of metal stents. Subsequently, we successfully obtained 3D coregistered PA/US ex vivo images using an iliac artery from a rabbit atherosclerosis model. Accordingly, lipid-rich plaques were sufficiently differentiated from normal tissue in the ex vivo experiment. We validated these findings histologically to confirm the lipid content.

  9. Intravascular behavior of a perfluorochemical emulsion.

    PubMed

    Tsuda, Y; Yamanouchi, K; Okamoto, H; Yokoyama, K; Heldebrant, C

    1990-03-01

    The purpose of this study was to clarify the reason why two similar perfluorochemical (PFC) emulsions, namely a mixed PFC (perfluorodecalin: FDC and perfluorotripropylamine: FTPA) and an FDC emulsion, resulted in a very different survival time for the exchange-transfused rats. Supposing that some difference in the intravascular behavior of both emulsions would account for such a difference in efficacy, experiments on behavior of PFC emulsions were carried out focusing on the particle size. It was reconfirmed that larger PFC particles were eliminated from the blood stream much more rapidly than smaller particles with three FMIQ (perfluoro-N-methyldecahydroisoquinoline) emulsions. After the FDC + FTPA emulsion or the FDC emulsion were injected into rabbits, PFC particles in the blood tended to decrease in size. When each of the collected blood samples was incubated at 37 degrees C for 24 h, the FDC emulsion enlarged in size markedly, but the FDC + FTPA emulsion showed no change. The retention of PFC particles appeared to depend on the emulsion stability rather than simply on the emulsifying agent alone. These data showed that some differences were observed in intravascular persistence of the FDC + FTPA emulsion and the FDC emulsion, and suggested that the efficacy of PFC emulsions would reflect their behavior in the circulation. PMID:2374085

  10. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1983

    SciTech Connect

    Baker, D.A.

    1984-08-01

    This document lists DOE's radioisotope production and distribution activities by its facilities at Argonne National Laboratory; Pacific Northwest Laboratory; Idaho Operations Office; Los Alamos National Laboratory; Oak Ridge National Laboratory; Savannah River Plant; and UNC Nuclear Industries, Inc. The information is divided into five sections: isotope suppliers, facility contacts, and isotopes or services supplied; lists of customers, suppliers and isotopes purchased; list of isotopes purchased cross-referenced to customer codes; geographic locations of radioisotope customers; and radioisotope sales and transfers - FY 1983.

  11. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1987

    SciTech Connect

    Lamar, D.A.; Van Houten, N.C.

    1988-08-01

    This edition of the radioisotope customer list was prepared at the request of the Office of Health and Environmental Research (ER-73), Office of Energy Research, US Department of Energy (DOE). This document describes radioisotope distribution from DOE facilities to private firms, including foreign and other DOE facilities. The information is divided into five sections: 1) isotope suppliers, facility contact, and isotopes or services supplied; 2) customers, suppliers, and isotopes purchased; 3) isotopes purchased cross- referenced with customer numbers; 4) geographic locations of radioisotope customers; and 5) radioisotope sales and transfers for fiscal year 1987.

  12. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1984

    SciTech Connect

    Baker, D.A.

    1985-08-01

    This edition of the radioisotope customer list was prepared at the request of the Office of Health and Environmental Research (ER-73), Office of Energy Research, Department of Energy (DOE). This document describes radioisotope distribution from DOE facilities to private firms including foreign and other DOE facilities. The information is divided into five sections: (1) isotope suppliers, facility contacts, and isotopes or services supplied; (2) customers, suppliers, and isotopes purchased; (3) isotopes purchased cross-referenced with customer numbers; (4) geographic locations of radioisotope customers; and (5) radioisotope sales and transfers - FY 1984.

  13. Advanced Radioisotope Power Systems Segmented Thermoelectric Research

    NASA Technical Reports Server (NTRS)

    Caillat, Thierry

    2004-01-01

    Flight times are long; - Need power systems with >15 years life. Mass is at an absolute premium; - Need power systems with high specific power and scalability. 3 orders of magnitude reduction in solar irradiance from Earth to Pluto. Nuclear power sources preferable. The Overall objective is to develop low mass, high efficiency, low-cost Advanced Radioisotope Power System with double the Specific Power and Efficiency over state-of-the-art Radioisotope Thermoelectric Generators (RTGs).

  14. Utilizing Radioisotope Power System Waste Heat for Spacecraft Thermal Management

    NASA Technical Reports Server (NTRS)

    Pantano, David R.; Dottore, Frank; Geng, Steven M.; Schrieber, Jeffrey G.; Tobery, E. Wayne; Palko, Joseph L.

    2005-01-01

    One of the advantages of using a Radioisotope Power System (RPS) for deep space or planetary surface missions is the readily available waste heat, which can be used to maintain electronic components within a controlled temperature range, to warm propulsion tanks and mobility actuators, and to gasify liquid propellants. Previous missions using Radioisotope Thermoelectric Generators (RTGs) dissipated a very large quantity of waste heat due to the relatively low efficiency of the thermoelectric conversion technology. The next generation RPSs, such as the 110-watt Stirling Radioisotope Generator (SRG110) will have much higher conversion efficiencies than their predecessors and therefore may require alternate approaches to transferring waste heat to the spacecraft. RTGs, with efficiencies of approx. 6 to 7% and 200 C housing surface temperatures, would need to use large and heavy radiator heat exchangers to transfer the waste heat to the internal spacecraft components. At the same time, sensitive spacecraft instruments must be shielded from the thermal radiation by using the heat exchangers or additional shields. The SRG110, with an efficiency around 22% and 50 C nominal housing surface temperature, can use the available waste heat more efficiently by more direct heat transfer methods such as heat pipes, thermal straps, or fluid loops. The lower temperatures allow the SRG110 much more flexibility to the spacecraft designers in configuring the generator without concern of overheating nearby scientific instruments, thereby eliminating the need for thermal shields. This paper will investigate using a high efficiency SRG110 for spacecraft thermal management and outline potential methods in several conceptual missions (Lunar Rover, Mars Rover, and Titan Lander) to illustrate the advantages with regard to ease of assembly, less complex interfaces, and overall mass savings.

  15. Intravascular spill of hyperosmolar urea during induced midtrimester abortion.

    PubMed

    Kovasznay, B M; Burkman, R T; Atienza, M F; King, T M

    1979-01-01

    Intravascular spill of hypertonic sodium chloride and the resultant serious and occasionally fatal consquences have been reported in association with induced midtrimester abortion. This report details 3 cases of intravascular spill of hyperosmolar urea. Although urea may pose less concern, because of its ability to readily cross cell membranes and its action as an osmotic diuretic, inadvertent intravascular spill can produce symptoms that include nausea, headache, sensations of warmth, and intense uterine cramping. In addition, abnormal blood pigments may occasionally be noted in the urine. Treatment includes intravenous hydration, careful monitoring of fluid/electrolyte balance and renal function, and avoiding the use of oxytocic agents.

  16. Quinine-Induced Disseminated Intravascular Coagulation.

    PubMed

    Abed, Firas; Baniya, Ramkaji; Bachuwa, Ghassan

    2016-01-01

    Every drug comes with some side effect. It is the benefit/risk ratio that determines the medical use of the drug. Quinine, a known antimalarial drug, has been used for nocturnal leg cramps since the 1930s; it is associated with severe life-threatening hematological and cardiovascular side effects. Disseminated intravascular coagulation (DIC), albeit rare, is a known coagulopathy associated with Quinine. It is imperative to inquire about the Quinine intake in medication history in patients with coagulopathy, as most patients still consider it a harmless home remedy for nocturnal leg cramps. In this report, we present a case of coagulopathy in a middle-aged woman, who gave a history of taking Quinine for nocturnal leg cramps, as her home remedy. Early identification of the offending agent led to the diagnosis, prompt discontinuation of the medication, and complete recovery and prevented the future possibility of recurrence. PMID:27293443

  17. [Disseminated intravascular coagulation: clinical and biological diagnosis].

    PubMed

    Touaoussa, Aziz; El Youssi, Hind; El Hassani, Imane; Hanouf, Daham; El Bergui, Imane; Zoulati, Ghizlane; Amrani Hassani, Moncef

    2015-01-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by the systemic activation of blood coagulation. Its pathophysiological mechanisms are complex and dependent on the underlying pathology, making the clinical and biological expression of quite variable DIC. Among the various biological parameters disrupted, most are not specific, and none of them allows in itself to make the diagnosis. All this does not facilitate the task of the practitioner for diagnosis of overt DIC, much less that of the non-overt DIC, early stage whose treatment would improve the prognosis. These considerations have led to develop scores, combining several parameters depending on their availability in daily practice, as well as their diagnostic relevance. Of all the scores, the ISTH (International society of thrombosis and hemostasis) remains the most used.

  18. Disseminated intravascular coagulation in burn injury.

    PubMed

    Lippi, Giuseppe; Ippolito, Luigi; Cervellin, Gianfranco

    2010-06-01

    Disseminated intravascular coagulation (DIC) is a complex and multifaceted disorder characterized by the activation of coagulation and fibrinolytic pathways, consumption of coagulation factors, and depletion of coagulation regulatory proteins. The introduction into the circulation of cellular debris characterized by strong thromboplastic activity due to tissue factor exposition or release (in or from burned tissues), which can thereby activate extrinsic pathway of coagulation system and trigger massive thrombin generation when present in sufficient concentration, represents the most plausible biological explanation to support the development of intravascular coagulation in patients with burn injury. Severe burns left untreated might also lead to an immunological and inflammatory response (activation of the complement cascade), which can amplify fibrinolysis and blood clotting. Overall, the real prevalence of DIC in patients with burns is as yet unclear. Postmortem, retrospective, and even longitudinal investigations are in fact biased by several factors, such as the objective difficulty to establish whether DIC might have occurred as a primary complication of burns or rather as a consequence of other superimposed pathologies (e.g., sepsis, multiple organ failure), the different diagnostic criteria for assessing DIC, and the heterogeneity of the patient samples studied. Nevertheless, the current scientific evidence is consistent with the hypothesis that biochemical changes suggestive for DIC (hypercoagulability, hypo- and hyperfibrinolysis) are commonplace in patients with burn trauma, and their severity increases exponentially with the severity of injury. Overt DIC seems to occur especially in critically ill burn patients or in those with severe burns (up to third degree) and large involvement of body surface area, in whom an appropriate therapy might be effective to prevent the otherwise fulminant course. Although early prophylaxis with antithrombin concentrates

  19. An Overview and Status of NASA's Radioisotope Power Conversion Technology NRA

    NASA Technical Reports Server (NTRS)

    Anderson, David J.; Wong, Wayne A.; Tuttle, Karen L.

    2005-01-01

    NASA's Advanced Radioisotope Power Systems (RPS) development program is developing next generation radioisotope power conversion technologies that will enable future missions that have requirements that can not be met by either photovoltaic systems or by current Radioisotope Power System (RPS) technology. The Advanced Power Conversion Research and Technology project of the Advanced RPS development program is funding research and technology activities through the NASA Research Announcement (NRA) 02- OSS-01, "Research Opportunities in Space Science 2002" entitled "Radioisotope Power Conversion Technology" (RPCT), 13 August 2002. The objective of the RPCT NRA is to advance the development of radioisotope power conversion technologies to provide significant improvements over the state-of-practice General Purpose Heat Source/Radioisotope Thermoelectric Generator by providing significantly higher efficiency to reduce the number of radioisotope fuel modules, and increase specific power (watts/kilogram). Other Advanced RPS goals include safety, long-life, reliability, scalability, multi-mission capability, resistance to radiation, and minimal interference with the scientific payload. These advances would enable a factor of 2 to 4 decrease in the amount of fuel required to generate electrical power. The RPCT NRA selected advanced RPS power conversion technology research and development proposals in the following three areas: innovative RPS power conversion research, RPS power conversion technology development in a nominal 100We scale; and, milliwatt/multi-watt RPS (mWRPS) power conversion research. Ten RPCT NRA contracts were awarded in 2003 in the areas of Brayton, Stirling, thermoelectric (TE), and thermophotovoltaic (TPV) power conversion technologies. This paper will provide an overview of the RPCT NRA, and a brief summary of accomplishments over the first 18 months but focusing on advancements made over the last 6 months.

  20. High Temperature Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    NASA Technical Reports Server (NTRS)

    Tarau, Calin; Walker, Kara L.; Anderson, William G.

    2009-01-01

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling convertor provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) is under development to allow multiple stops and restarts of the Stirling convertor. The status of the ongoing effort in developing this technology is presented in this paper. An earlier, preliminary design had a radiator outside the Advanced Stirling Radioisotope Generator (ASRG) casing, used NaK as the working fluid, and had the reservoir located on the cold side adapter flange. The revised design has an internal radiator inside the casing, with the reservoir embedded inside the insulation. A large set of advantages are offered by this new design. In addition to reducing the overall size and mass of the VCHP, simplicity, compactness and easiness in assembling the VCHP with the ASRG are significantly enhanced. Also, the permanently elevated temperatures of the entire VCHP allows the change of the working fluid from a binary compound (NaK) to single compound (Na). The latter, by its properties, allows higher performance and further mass reduction of the system. Preliminary design and analysis shows an acceptable peak temperature of the ASRG case of 140 C while the heat losses caused by the addition of the VCHP are 1.8 W.

  1. Utilizing Radioisotope Power Systems for Human Lunar Exploration

    NASA Technical Reports Server (NTRS)

    Schreiner, Timothy M.

    2005-01-01

    The Vision for Space Exploration has a goal of sending crewed missions to the lunar surface as early as 2015 and no later than 2020. The use of nuclear power sources could aid in assisting crews in exploring the surface and performing In-Situ Resource Utilization (ISRU) activities. Radioisotope Power Systems (RPS) provide constant sources of electrical power and thermal energy for space applications. RPSs were carried on six of the crewed Apollo missions to power surface science packages, five of which still remain on the lunar surface. Future RPS designs may be able to play a more active role in supporting a long-term human presence. Due to its lower thermal and radiation output, the planned Stirling Radioisotope Generator (SRG) appears particularly attractive for manned applications. The MCNPX particle transport code has been used to model the current SRG design to assess its use in proximity with astronauts operating on the surface. Concepts of mobility and ISRU infrastructure were modeled using MCNPX to analyze the impact of RPSs on crewed mobility systems. Strategies for lowering the radiation dose were studied to determine methods of shielding the crew from the RPSs.

  2. Radioisotope Production for Medical and Physics Applications

    NASA Astrophysics Data System (ADS)

    Mausner, Leonard

    2012-10-01

    Radioisotopes are critical to the science and technology base of the US. Discoveries and applications made as a result of the availability of radioisotopes span widely from medicine, biology, physics, chemistry and homeland security. The clinical use of radioisotopes for medical diagnosis is the largest sector of use, with about 16 million procedures a year in the US. The use of ^99Mo/^99mTc generator and ^18F make up the majority, but ^201Tl, ^123I, ^111In, and ^67Ga are also used routinely to perform imaging of organ function. Application of radioisotopes for therapy is dominated by use of ^131I for thyroid malignancies, ^90Y for some solid tumors, and ^89Sr for bone cancer, but production of several more exotic species such as ^225Ac and ^211At are of significant current research interest. In physics ^225Ra is of interest for CP violation studies, and the actinides ^242Am, ^249Bk, and ^254Es are needed as targets for experiments to create superheavy elements. Large amounts of ^252Cf are needed as a fission source for the CARIBU experiment at ANL. The process of radioisotope production is multidisciplinary. Nuclear physics input based on nuclear reaction excitation function data is needed to choose an optimum target/projectile in order to maximize desired isotope production and minimize unwanted byproducts. Mechanical engineering is needed to address issues of target heating, induced mechanical stress and material compatibility of target and claddings. Radiochemists are involved as well since chemical separation to purify the desired final radioisotope product from the bulk target and impurities is also usually necessary. Most neutron rich species are produced at a few government and university reactors. Other radioisotopes are produced in cyclotrons in the commercial sector, university/hospital based facilities, and larger devices at the DOE labs. The landscape of US facilities, the techniques involved, and current supply challenges will be reviewed.

  3. Stirling Radioisotope Power System as an Alternative for NASAs Deep Space Missions

    NASA Astrophysics Data System (ADS)

    Shaltens, R. K.; Mason, L. S.; Schreiber, J. G.

    2001-01-01

    The NASA Glenn Research Center (GRC) and the Department of Energy (DOE) are developing a free-piston Stirling convertor for a Stirling Radioisotope Power System (SRPS) to provide on-board electric power for future NASA deep space missions. The SRPS currently being developed provides about 100 watts and reduces the amount of radioisotope fuel by a factor of four over conventional Radioisotope Thermoelectric Generators (RTG). The present SRPS design has a specific power of approximately 4 W/kg which is comparable to an RTG. GRC estimates for advanced versions of the SRPS with improved heat source integration, lightweight Stirling convertors, composite radiators, and chip-packaged controllers improves the specific mass to about 8 W/kg. Additional information is contained in the original extended abstract.

  4. 21 CFR 882.5150 - Intravascular occluding catheter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... Class III (premarket approval). (c) Date PMA or notice of completion of a PDP is required. A PMA or a... intravascular occluding catheter shall have an approved PMA or a declared completed PDP in effect before...

  5. 21 CFR 882.5150 - Intravascular occluding catheter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... Class III (premarket approval). (c) Date PMA or notice of completion of a PDP is required. A PMA or a... intravascular occluding catheter shall have an approved PMA or a declared completed PDP in effect before...

  6. Intravascular laser therapy in different forms of lung diseases

    NASA Astrophysics Data System (ADS)

    Kirillov, M. N.; Reshetnikov, V. A.; Kazhekin, O. A.; Shepelenko, A. F.

    1993-06-01

    The potentions of laser intravascular therapy in elimination of pyogenic and inflammatory intoxication in cases of acute pneumonia, pyo-destructive diseases (including posttraumatic diseases) of the lungs are studied clinically.

  7. Development of Next Generation Segmented Thermoelectric Radioisotope Power Systems

    NASA Astrophysics Data System (ADS)

    Fleurial, J.; Caillat, T.; Ewell, R. C.

    2005-12-01

    Radioisotope thermoelectric generators have been used for space-based applications since 1961 with a total of 22 space missions that have successfully used RTGs for electrical power production. The key advantages of radioisotope thermoelectric generators (RTGs) are their long life, robustness, compact size, and high reliability. Thermoelectric converters are easily scalable, and possess a linear current-voltage curve, making power generation easy to control via a shunt regulator and shunt radiator. They produce no noise, vibration or torque during operation. These properties have made RTGs ideally suitable for autonomous missions in the extreme environments of outer space and on planetary surfaces. More advanced radioisotope power systems (RPS) with higher specific power (W/kg) and/or power output are desirable for future NASA missions, including the Europa Geophysical Orbiter mission. For the past few years, the Jet Propulsion Laboratory (JPL) has been developing more efficient thermoelectric materials and has demonstrated significant increases in the conversion efficiency of high temperature thermocouples, up to 14% when operated across a 975K to 300K temperature differential. In collaboration with NASA Glenn Research Center, universities (USC and UNM), Ceramic and Metal Composites Corporation and industrial partners, JPL is now planning to lead the research and development of advanced thermoelectric technology for integration into the next generations of RPS. Preliminary studies indicate that this technology has the potential for improving the RPS specific power by more than 50% over the current state-of-the-art multi-mission RTG being built for the Mars Science Laboratory mission. A second generation advanced RPS is projected at more than doubling the specific power.

  8. Development of Advanced Stirling Radioisotope Generator for Space Exploration

    NASA Technical Reports Server (NTRS)

    Chan, Jack; Wood, J. Gary; Schreiber, Jeffrey G.

    2007-01-01

    Under the joint sponsorship of the Department of Energy and NASA, a radioisotope power system utilizing Stirling power conversion technology is being developed for potential future space missions. The higher conversion efficiency of the Stirling cycle compared with that of Radioisotope Thermoelectric Generators (RTGs) used in previous missions (Viking, Pioneer, Voyager, Galileo, Ulysses, Cassini, and New Horizons) offers the advantage of a four-fold reduction in PuO2 fuel, thereby saving cost and reducing radiation exposure to support personnel. With the advancement of state-of-the-art Stirling technology development under the NASA Research Announcement (NRA) project, the Stirling Radioisotope Generator program has evolved to incorporate the advanced Stirling convertor (ASC), provided by Sunpower, into an engineering unit. Due to the reduced envelope and lighter mass of the ASC compared to the previous Stirling convertor, the specific power of the flight generator is projected to increase from 3.5 to 7 We/kg, along with a 25 percent reduction in generator length. Modifications are being made to the ASC design to incorporate features for thermal, mechanical, and electrical integration with the engineering unit. These include the heat collector for hot end interface, cold-side flange for waste heat removal and structural attachment, and piston position sensor for ASC control and power factor correction. A single-fault tolerant, active power factor correction controller is used to synchronize the Stirling convertors, condition the electrical power from AC to DC, and to control the ASCs to maintain operation within temperature and piston stroke limits. Development activities at Sunpower and NASA Glenn Research Center (GRC) are also being conducted on the ASC to demonstrate the capability for long life, high reliability, and flight qualification needed for use in future missions.

  9. Development of Advanced Stirling Radioisotope Generator for Space Exploration

    NASA Astrophysics Data System (ADS)

    Chan, Jack; Wood, J. Gary; Schreiber, Jeffrey G.

    2007-01-01

    Under the joint sponsorship of the Department of Energy and NASA, a radioisotope power system utilizing Stirling power conversion technology is being developed for potential future space missions. The higher conversion efficiency of the Stirling cycle compared with that of Radioisotope Thermoelectric Generators (RTGs) used in previous missions (Viking, Pioneer, Voyager, Galileo, Ulysses, Cassini, and New Horizons) offers the advantage of a four-fold reduction in PuO2 fuel, thereby saving cost and reducing radiation exposure to support personnel. With the advancement of state-of-the-art Stirling technology development under the NASA Research Announcement (NRA) project, the Stirling Radioisotope Generator program has evolved to incorporate the advanced Stirling convertor (ASC), provided by Sunpower, into an engineering unit. Due to the reduced envelope and lighter mass of the ASC compared to the previous Stirling convertor, the specific power of the flight generator is projected to increase from 3.5 We/kg to 7 We/kg, along with a 25% reduction in generator length. Modifications are being made to the ASC design to incorporate features for thermal, mechanical, and electrical integration with the engineering unit. These include the heat collector for hot end interface, cold-side flange for waste heat removal and structural attachment, and piston position sensor for ASC control and power factor correction. A single-fault tolerant, active power factor correction controller is used to synchronize the Stirling convertors, condition the electrical power from AC to DC, and to control the ASCs to maintain operation within temperature and piston stroke limits. Development activities at Sunpower and NASA Glenn Research Center (GRC) are also being conducted on the ASC to demonstrate the capability for long life, high reliability, and flight qualification needed for use in future missions.

  10. NASA's Radioisotope Power Systems Program Status

    NASA Technical Reports Server (NTRS)

    Dudzinski, Leonard A.; Hamley, John A.; McCallum, Peter W.; Sutliff, Thomas J.; Zakrajsek, June F.

    2013-01-01

    NASA's Radioisotope Power Systems (RPS) Program began formal implementation in December 2010. The RPS Program's goal is to make available RPS for the exploration of the solar system in environments where conventional solar or chemical power generation is impractical or impossible to meet mission needs. To meet this goal, the RPS Program manages investments in RPS system development and RPS technologies. The current keystone of the RPS Program is the development of the Advanced Stirling Radioisotope Generator (ASRG). This generator will be about four times more efficient than the more traditional thermoelectric generators, while providing a similar amount of power. This paper provides the status of the RPS Program and its related projects. Opportunities for RPS generator development and targeted research into RPS component performance enhancements, as well as constraints dealing with the supply of radioisotope fuel, are also discussed in the context of the next ten years of planetary science mission plans.

  11. RADIOISOTOPE INVENTORY FOR TSPA-SR

    SciTech Connect

    C. Leigh; R. Rechard

    2001-01-30

    The total system performance assessment for site recommendation (TSPA-SR), on Yucca Mountain, as a site (if suitable) for disposal of radioactive waste, consists of several models. The Waste Form Degradation Model (i.e, source term) of the TSPA-SR, in turn, consists of several components. The Inventory Component, discussed here, defines the inventory of 26 radioisotopes for three representative waste categories: (1) commercial spent nuclear fuel (CSNF), (2) US Department of Energy (DOE) spent nuclear fuel (DSNF), and (3) high-level waste (HLW). These three categories are contained and disposed of in two types of waste packages (WPs)--CSNF WPs and co-disposal WPs, with the latter containing both DSNF and HLW. Three topics are summarized in this paper: first, the transport of radioisotopes evaluated in the past; second, the development of the inventory for the two WP types; and third, the selection of the most important radioisotopes to track in TSPA-SR.

  12. Intravascular probe for detection of vulnerable plaque

    NASA Astrophysics Data System (ADS)

    Patt, Bradley E.; Iwanczyk, Jan S.; MacDonald, Lawrence R.; Yamaguchi, Yuko; Tull, Carolyn R.; Janecek, Martin; Hoffman, Edward J.; Strauss, H. William; Tsugita, Ross; Ghazarossian, Vartan

    2001-12-01

    Coronary angiography is unable to define the status of the atheroma, and only measures the luminal dimensions of the blood vessel, without providing information about plaque content. Up to 70% of heart attacks are caused by minimally obstructive vulnerable plaques, which are too small to be detected adequately by angiography. We have developed an intravascular imaging detector to identify vulnerable coronary artery plaques. The detector works by sensing beta or conversion electron radiotracer emissions from plaque-binding radiotracers. The device overcomes the technical constraints of size, sensitivity and conformance to the intravascular environment. The detector at the distal end of the catheter uses six 7mm long by 0.5mm diameter scintillation fibers coupled to 1.5m long plastic fibers. The fibers are offset from each other longitudinally by 6mm and arranged spirally around a guide wire in the catheter. At the proximal end of the catheter the optical fibers are coupled to an interface box with a snap on connector. The interface box contains a position sensitive photomultiplier tube (PSPMT) to decode the individual fibers. The whole detector assembly fits into an 8-French (2.7 mm in diameter) catheter. The PSPMT image is further decoded with software to give a linear image, the total instantaneous count rate and an audio output whose tone corresponds to the count rate. The device was tested with F-18 and Tl-204 sources. Spectrometric response, spatial resolution, sensitivity and beta to background ratio were measured. System resolution is 6 mm and the sensitivity is >500 cps / micrometers Ci when the source is 1 mm from the detector. The beta to background ratio was 11.2 for F-18 measured on a single fiber. The current device will lead to a system allowing imaging of labeled vulnerable plaque in coronary arteries. This type of signature is expected to enable targeted and cost effective therapies to prevent acute coronary artery diseases such as: unstable angina

  13. Commercial Superconducting Electron Linac for Radioisotope Production

    SciTech Connect

    Grimm, Terry Lee; Boulware, Charles H.; Hollister, Jerry L.; Jecks, Randall W.; Mamtimin, Mayir; Starovoitova, Valeriia

    2015-08-13

    The majority of radioisotopes used in the United States today come from foreign suppliers or are generated parasitically in large government accelerators and nuclear reactors. Both of these restrictions limit the availability of radioisotopes and discourage the development and evaluation of new isotopes and for nuclear medicine, science, and industry. Numerous studies have been recommending development of dedicated accelerators for production of radioisotopes for over 20 years (Institute of Medicine, 1995; Reba, et al, 2000; National Research Council, 2007; NSAC 2009). The 2015 NSAC Long Range Plan for Isotopes again identified electron accelerators as an area for continued research and development. Recommendation 1(c) from the 2015 NSAC Isotope report specifically identifies electron accelerators for continued funding for the purpose of producing medical and industrial radioisotopes. Recognizing the pressing need for new production methods of radioisotopes, the United States Congress passed the American Medical Isotope Production Act of 2012 to develop a domestic production of 99Mo and to eliminate the use of highly enriched uranium (HEU) in the production of 99Mo. One of the advantages of high power electron linear accelerators (linacs) is they can create both proton- and neutron-rich isotopes by generating high energy x-rays that knock out protons or neutrons from stable atoms or by fission of uranium. This allows for production of isotopes not possible in nuclear reactors. Recent advances in superconducting electron linacs have decreased the size and complexity of these systems such that they are economically competitive with nuclear reactors and large, high energy accelerators. Niowave, Inc. has been developing a radioisotope production facility based on a superconducting electron linac with liquid metal converters.

  14. Self-reciprocating radioisotope-powered cantilever

    NASA Astrophysics Data System (ADS)

    Li, Hui; Lal, Amit; Blanchard, James; Henderson, Douglass

    2002-07-01

    A reciprocating cantilever utilizing emitted charges from a millicurie radioisotope thin film is presented. The actuator realizes a direct collected-charge-to-motion conversion. The reciprocation is obtained by self-timed contact between the cantilever and the radioisotope source. A static model balancing the electrostatic and mechanical forces from an equivalent circuit leads to an analytical solution useful for device characterization. Measured reciprocating periods agree with predicted values from the analytical model. A scaling analysis shows that microscale arrays of such cantilevers provide an integrated sensor and actuator platform.

  15. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1982

    SciTech Connect

    Richards, M.P.

    1983-08-01

    The radioisotope production and distribution activities by facilities at Argonne National Laboratory, Pacific Northwest Laboratory, Brookhaven National Laboratory, Hanford Engineering Development Laboratory, Idaho Operations Office, Los Alamos Scientific Laboratory, Oak Ridge National Laboratory, Savannah River Laboratory, and UNC Nuclear Industries, Inc. are listed. The information is divided into five sections: isotope suppliers, facility, contacts, and isotopes or services supplied; alphabetical list of customers, and isotopes purchased; alphabetical list of isotopes cross-referenced to customs numbers; geographical location of radioisotope customers; and radioisotope sales and transfers-FY 1982. (MHR)

  16. Cardiac phase detection in intravascular ultrasound images

    NASA Astrophysics Data System (ADS)

    Matsumoto, Monica M. S.; Lemos, Pedro Alves; Yoneyama, Takashi; Furuie, Sergio Shiguemi

    2008-03-01

    Image gating is related to image modalities that involve quasi-periodic moving organs. Therefore, during intravascular ultrasound (IVUS) examination, there is cardiac movement interference. In this paper, we aim to obtain IVUS gated images based on the images themselves. This would allow the reconstruction of 3D coronaries with temporal accuracy for any cardiac phase, which is an advantage over the ECG-gated acquisition that shows a single one. It is also important for retrospective studies, as in existing IVUS databases there are no additional reference signals (ECG). From the images, we calculated signals based on average intensity (AI), and, from consecutive frames, average intensity difference (AID), cross-correlation coefficient (CC) and mutual information (MI). The process includes a wavelet-based filter step and ascendant zero-cross detection in order to obtain the phase information. Firstly, we tested 90 simulated sequences with 1025 frames each. Our method was able to achieve more than 95.0% of true positives and less than 2.3% of false positives ratio, for all signals. Afterwards, we tested in a real examination, with 897 frames and ECG as gold-standard. We achieved 97.4% of true positives (CC and MI), and 2.5% of false positives. For future works, methodology should be tested in wider range of IVUS examinations.

  17. Immunological characterization of pulmonary intravascular macrophages

    NASA Technical Reports Server (NTRS)

    Chitko-McKown, C. G.; Reddy, D. N.; Chapes, S. K.; McKown, R. D.; Blecha, F.; Spooner, B. S. (Principal Investigator)

    1992-01-01

    Pulmonary intravascular macrophages (PIMs) are lung macrophages found apposed to the endothelium of pulmonary capillaries. In many species, they are responsible for the clearance of blood-borne particulates and pathogens; however, little else is known about their roles as immunologic effector cells. We compared PIMs with pulmonary alveolar macrophages (PAMs) to determine the relative immunological activities of these two cell populations. Our results suggested that both populations possess similar phagocytic and bactericidal activities. In assays measuring cytotoxicity, PIMs were more cytotoxic than PAMs against virally infected target cells; however, differences between these macrophage populations were not as marked when noninfected targets were used. LPS-stimulated PIMs produced more T-cell proliferative cytokines than PAMs, and both populations of nonstimulated macrophages produced similar amounts of the cytokines. In contrast, PAMs produced more TNF alpha and NO2- than PIMs when both populations were stimulated with LPS; however, nonstimulated PAMs and PIMs produced similar amounts of TNF alpha and NO2. These data suggest that bovine PIMs are immunologically active. Differences between the degrees of activity of PIMs and PAMs indicate that these macrophage populations may have different roles in lung surveillance.

  18. [Infection prevention and control in intravascular devices].

    PubMed

    Colombo, D; Russolillo, C

    2003-04-01

    Intravascular devices (IVD) are indispensable in the care of the critical patient; even so, their use can be complicated by infection, which is generally associated with longer hospital stay and ensuing higher hospital costs. It is therefore imperative that guidelines are applied that constitute a basis of information upon which the individual facility can develop its own strategy. The strategy can be outlined under the following points: a) staff training, b) surveillance of IVD-associated infections, c) hand washing, d) barrier measures during catheter introduction and management, e) insertion site management and medication systems for the insertion site, f) choice and replacement of the IVD, g) replacement of intravenous administration devices and liquids, h) antimicrobial prophylaxis. In the management of central venous catheters (CVC), recommendations call for: 1) the use of a single lumen CVC, unless multiple accesses are needed; 2) the peripheral placement of CVCs, both in the use of tunneled catheters and/or implantable vascular devices in patients over 4 years of age in which long-term vascular access (> 30 days) is planned; 3) the use of completely implantable devices in pediatric patients less than 4 years of age requiring long-term vascular access; 4) the use of the subclavian artery as the site of CVC insertion unless clinically contraindicated (e.g. coagulopathy, anatomic alterations); 5) the application of barrier precautions during CVC introduction and in the management of the catheter and the insertion site. PMID:12766724

  19. Laboratory testing in disseminated intravascular coagulation.

    PubMed

    Favaloro, Emmanuel J

    2010-06-01

    The diagnosis of disseminated intravascular coagulation (DIC) relies on clinical signs and symptoms, identification of the underlying disease, the results of laboratory testing, and differentiation from other pathologies. The clinical features mainly depend on the underlying cause of the DIC. The laboratory diagnosis of DIC uses a combination of tests because no single test result alone can firmly establish or rule out the diagnosis. Global tests of hemostasis may initially provide evidence of coagulation activation and later in the process provide evidence of consumption of coagulation factors, but their individual diagnostic efficiency is limited. Fibrinolytic markers, in particular D-dimer, are reflective of activation of both coagulation and fibrinolysis, so that a normal finding can be useful for ruling-out DIC. Decreased levels of the natural anticoagulants (in particular, antithrombin and protein C) are frequently observed in patients with DIC, but their measurement is not normally incorporated into standard diagnostic algorithms. New tests are being explored for utility in DIC, and some additional tests may be useful on a case-by-case basis, depending on the proposed cause of the DIC or their local availability. For example, clot waveform analysis is useful but currently limited to a single instrument. Also, procalcitonin is an inflammatory biomarker that may be useful within the context of septic DIC, and activated factor X clotting time is an emerging test of procoagulant phospholipids that also seems to hold promise in DIC.

  20. Intravascular Neural Interface with Nanowire Electrode

    PubMed Central

    Watanabe, Hirobumi; Takahashi, Hirokazu; Nakao, Masayuki; Walton, Kerry; Llinás, Rodolfo R.

    2010-01-01

    Summary A minimally invasive electrical recording and stimulating technique capable of simultaneously monitoring the activity of a significant number (e.g., 103 to 104) of neurons is an absolute prerequisite in developing an effective brain–machine interface. Although there are many excellent methodologies for recording single or multiple neurons, there has been no methodology for accessing large numbers of cells in a behaving experimental animal or human individual. Brain vascular parenchyma is a promising candidate for addressing this problem. It has been proposed [1, 2] that a multitude of nanowire electrodes introduced into the central nervous system through the vascular system to address any brain area may be a possible solution. In this study we implement a design for such microcatheter for ex vivo experiments. Using Wollaston platinum wire, we design a submicron-scale electrode and develop a fabrication method. We then evaluate the mechanical properties of the electrode in a flow when passing through the intricacies of the capillary bed in ex vivo Xenopus laevis experiments. Furthermore, we demonstrate the feasibility of intravascular recording in the spinal cord of Xenopus laevis. PMID:21572940

  1. Endotoxin Induced Disseminated Intravascular Coagulation in Cattle

    PubMed Central

    Thomson, G. W.; McSherry, B. J.; Valli, V. E. O.

    1974-01-01

    Endotoxin administered intravenously to a group of four calves resulted in disseminated intravascular coagulation. A sublethal dose of piromen, a commercially available Pseudomonas spp endotoxin, was used. Serial measurements of total plasma fibrinogen, soluble fibrin levels, ethanol gelation tests, protamine sulfate tests, fibrinogen-fibrin-related antigen (FR-antigen) and prothrombin and thrombin times were done. Initial depression of plasma fibrinogen with a nadir of about 40% of pre-endotoxin levels at eight to 11 hours post-endotoxin (+8 to +11 hours) followed by an overcompensation to 180% at +60 to +108 hours was shown. Soluble fibrin was demonstrated in plasma from +2 to +22 hours with a peak of 100-114 mg/100 ml at +4 to +9 hours. Positive plasma ethanol gelation and protamine sulfate tests, as well as the presence of serum FR-antigen, occurred consistently following endotoxin administration. Significant increases in prothrombin times (PT) from +4 to +40 hours and in thrombin times (TT) from +4 to +16 hours were demonstrated. The peak increase of PT at +8 to +10 hours was 180%. The peak increase of TT at +6 to +9 hours was 260-290%. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 4. PMID:4279765

  2. The basics of intravascular optical coherence tomography.

    PubMed

    Roleder, Tomasz; Jąkała, Jacek; Kałuża, Grzegorz L; Partyka, Łukasz; Proniewska, Klaudia; Pociask, Elżbieta; Zasada, Wojciech; Wojakowski, Wojciech; Gąsior, Zbigniew; Dudek, Dariusz

    2015-01-01

    Optical coherence tomography (OCT) has opened new horizons for intravascular coronary imaging. It utilizes near-infrared light to provide a microscopic insight into the pathology of coronary arteries in vivo. Optical coherence tomography is also capable of identifying the chemical composition of atherosclerotic plaques and detecting traits of their vulnerability. At present it is the only tool to measure the thickness of the fibrous cap covering the lipid core of the atheroma, and thus it is an exceptional modality to detect plaques that are prone to rupture (thin fibrous cap atheromas). Moreover, it facilitates distinguishing between plaque rupture and plaque erosion as a cause of acute intracoronary thrombosis. Optical coherence tomography is applied to guide angioplasties of coronary lesions and to assess outcomes of percutaneous coronary interventions broadly. It identifies stent malapposition, dissections, and thrombosis with unprecedented precision. Furthermore, OCT helps to monitor vessel healing after stenting. It evaluates the coverage of stent struts by the neointima and detects in-stent neoatherosclerosis. With so much potential, new studies are warranted to determine OCT's clinical impact. The following review presents the technical background, basics of OCT image interpretation, and practical tips for adequate OCT imaging, and outlines its established and potential clinical application.

  3. Sodium Variable Conductance Heat Pipe for Radioisotope Stirling Systems

    NASA Technical Reports Server (NTRS)

    Tarau, Calin; Anderson, William G.; Walker, Kara

    2009-01-01

    In a Stirling radioisotope system, heat must continually be removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. Normally, the Stirling convertor provides this cooling. If the converter stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, and also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) has been designed to allow multiple stops and restarts of the Stirling convertor in an Advanced Stirling Radioisotope Generator (ASRG). When the Stirling convertor is turned off, the VCHP will activate when the temperatures rises 30 C above the setpoint temperature. A prototype VCHP with sodium as the working fluid was fabricated and tested in both gravity aided and against gravity conditions for a nominal heater head temperature of 790 C. The results show very good agreement with the predictions and validate the model. The gas front was located at the exit of the reservoir when heater head temperature was 790 C while cooling was ON, simulating an operating Advanced Stirling Converter (ASC). When cooling stopped, the temperature increased by 30 C, allowing the gas front to move past the radiator, which transferred the heat to the case. After resuming the cooling flow, the front returned at the initial location turning OFF the VCHP. The against gravity working conditions showed a colder reservoir and faster transients.

  4. A multi-functional electronic program for the management of radioisotopes.

    PubMed

    Ritchot, Nathalie; Santary, William

    2008-05-01

    Everyone will agree that specialized computer programs have done away with the many tedious tasks associated with manually keeping track of radioisotopes. Enhanced electronic programs have virtually cut the time of managing radioisotopes. Agriculture and Agri-Food, Canada's (AAFC) program for the management of radioisotopes, is somewhat different from most electronic programs. It is divided into three levels of management that are dependent on the roles that a user might have when applying the application. These roles include the Departmental Radiation Safety Officer (DRSO), Radiation Safety Officer (RSO), and authorized user, which meets the requirements of the Canadian Nuclear Safety Commission. The DRSO and authorized AAFC Radiation Safety Committee members have access to the first level of management. This is the highest level of control, and only the DRSO has permission to add a nuclear substance to the system with the approval of the Canadian Nuclear Safety Commission (CNSC). This level of management is also responsible for adding authorized users, locations, and managing the Internal Use Permits. The second level of management is for site-specific RSOs. They have access to all information regarding their center of activity, but they cannot change Internal Use Permit data. The RSOs can reset passwords, authorize new users, control the maximum activity limit, etc., but are limited to viewing only the information that relates to their internal use permit. However, they retain significant control within the permit. The third and last level of management is for authorized users who can access the radioisotope order-distribution-disposal section, waste or storage containers creation file, and leak/wipe test procedures. As in the case of the DRSO and RSO, they also have access to all reports and inventories for their center of activity but they cannot change Internal Use Permit or inventories data. This program has proven to be a valuable tool for scientific staff

  5. A multi-functional electronic program for the management of radioisotopes.

    PubMed

    Ritchot, Nathalie; Santary, William

    2008-05-01

    Everyone will agree that specialized computer programs have done away with the many tedious tasks associated with manually keeping track of radioisotopes. Enhanced electronic programs have virtually cut the time of managing radioisotopes. Agriculture and Agri-Food, Canada's (AAFC) program for the management of radioisotopes, is somewhat different from most electronic programs. It is divided into three levels of management that are dependent on the roles that a user might have when applying the application. These roles include the Departmental Radiation Safety Officer (DRSO), Radiation Safety Officer (RSO), and authorized user, which meets the requirements of the Canadian Nuclear Safety Commission. The DRSO and authorized AAFC Radiation Safety Committee members have access to the first level of management. This is the highest level of control, and only the DRSO has permission to add a nuclear substance to the system with the approval of the Canadian Nuclear Safety Commission (CNSC). This level of management is also responsible for adding authorized users, locations, and managing the Internal Use Permits. The second level of management is for site-specific RSOs. They have access to all information regarding their center of activity, but they cannot change Internal Use Permit data. The RSOs can reset passwords, authorize new users, control the maximum activity limit, etc., but are limited to viewing only the information that relates to their internal use permit. However, they retain significant control within the permit. The third and last level of management is for authorized users who can access the radioisotope order-distribution-disposal section, waste or storage containers creation file, and leak/wipe test procedures. As in the case of the DRSO and RSO, they also have access to all reports and inventories for their center of activity but they cannot change Internal Use Permit or inventories data. This program has proven to be a valuable tool for scientific staff

  6. Rotational multispectral fluorescence lifetime imaging and intravascular ultrasound: bimodal system for intravascular applications

    PubMed Central

    Ma, Dinglong; Bec, Julien; Yankelevich, Diego R.; Gorpas, Dimitris; Fatakdawala, Hussain; Marcu, Laura

    2014-01-01

    Abstract. We report the development and validation of a hybrid intravascular diagnostic system combining multispectral fluorescence lifetime imaging (FLIm) and intravascular ultrasound (IVUS) for cardiovascular imaging applications. A prototype FLIm system based on fluorescence pulse sampling technique providing information on artery biochemical composition was integrated with a commercial IVUS system providing information on artery morphology. A customized 3-Fr bimodal catheter combining a rotational side-view fiberoptic and a 40-MHz IVUS transducer was constructed for sequential helical scanning (rotation and pullback) of tubular structures. Validation of this bimodal approach was conducted in pig heart coronary arteries. Spatial resolution, fluorescence detection efficiency, pulse broadening effect, and lifetime measurement variability of the FLIm system were systematically evaluated. Current results show that this system is capable of temporarily resolving the fluorescence emission simultaneously in multiple spectral channels in a single pullback sequence. Accurate measurements of fluorescence decay characteristics from arterial segments can be obtained rapidly (e.g., 20 mm in 5 s), and accurate co-registration of fluorescence and ultrasound features can be achieved. The current finding demonstrates the compatibility of FLIm instrumentation with in vivo clinical investigations and its potential to complement conventional IVUS during catheterization procedures. PMID:24898604

  7. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1980

    SciTech Connect

    Burlison, J.S.

    1981-08-01

    The sixteenth edition of the radioisotope customer list was prepared at the request of the Office of Health and Environmental Research, Office of energy Research, Department of Energy (DOE). This document lists DOE's radioisotope production and distribution activities by its facilities at Argonne National Laboratory; Pacific Northwest Laboratory; Brookhaven National Laboraory; Hanford Engineering Development Laboratory; Idaho Operations Office; Los Alamos Scientific Laboratory; Mound Facility; Oak Ridge National Laboratory; Savannah River Laboratory; and UNC Nuclear Industries, Inc. The information is divided into five sections: (1) isotope suppliers, facility, contracts and isotopes or services supplied; (2) alphabetical list of customers, and isotopes purchased; (3) alphabetical list of isotopes cross-referenced to customer numbers; (4) geographical location of radioisotope customers; and (5) radioisotope sales and transfers-FY 1980.

  8. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1981

    SciTech Connect

    Burlison, J.S.

    1982-09-01

    The seventeenth edition of the radioisotope customer list was prepared at the request of the Office of Health and Environmental Research, Office of Energy Research, Department of Energy (DOE). This document lists DOE's radioisotope production and distribution activities by its facilities at Argonne National Laboratory: Pacific Northwest Laboratory; Brookhaven National Laboratory; Hanford Engineering Development Laboratory; Idaho Operations Office; Los Alamos Scientific Laboratory; Mound Facility; Oak Ridge National Laboratory; Savannah River Laboratory; and UNC Nuclear Industries, Inc. The information is divided into five sections: (1) isotope suppliers, facility, contracts and isotopes or services supplied; (2) alphabetical list of customers, and isotopes purchased; (3) alphabetical list of isotopes cross-referenced to customer numbers; (4) geographical location of radioisotope customers; and (5) radioisotope sales and transfers-FY 1980.

  9. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1979

    SciTech Connect

    Burlison, J.S.

    1980-06-01

    The fifteenth edition of the radioisotope customer list was prepared at the request of the Division of Financial Services, Office of the Assistant Secretary for Environment, Department of Energy (DOE). This document lists DOE's radioisotope production and distribution activities by its facilities at Argonne National Laboratory; Pacific Northwest Laboratory; Brookhaven National Laboratory; Hanford Engineering Development Laboratory; Idaho Operations Office; Los Alamos Scientific Laboratory; Mound Facility; Oak Ridge National Laboratory; Rocky Flats Area Office; Savannah River Laboratory; and UNC Nuclear Industries, Inc. The information is divided into five sections: Isotope suppliers, facility, contracts and isotopes or services supplied; alphabetical list of customers, and isotopes purchased; alphabetical list of isotopes cross-referenced to customer numbers; geographical location of radioisotope customers; and radioisotope sales and transfers-FY 1979.

  10. ILLUSTRATIONS OF RADIOISOTOPES--DEFINITIONS AND APPLICATIONS.

    ERIC Educational Resources Information Center

    Atomic Energy Commission, Oak Ridge, TN. Div. of Technical Information.

    THIS PUBLICATION IS COMPOSED OF OVER 150 PAGES OF BLACK AND WHITE ILLUSTRATIONS DEALING WITH RADIOISOTOPES AND THEIR USES. THESE ILLUSTRATIONS CONSIST OF CHARTS, GRAPHS, AND PICTORIAL REPRESENTATIONS WHICH COULD BE PREPARED AS HANDOUTS, TRANSPARENCIES FOR OVERHEAD PROJECTION, OR WHICH COULD BE USED IN A NUMBER OF OTHER WAYS FOR PRESENTING SUCH…

  11. Radioisotope thermal generator (RTG) power conditioner

    NASA Technical Reports Server (NTRS)

    Stacey, W. S.

    1974-01-01

    New regulator: (a) permits operation with high-impedance radioisotope thermal generators at conversion efficiencies typically above 90%; (b) does not require input filtering; (c) eliminates current spiking; and (d) is simple, efficient, and reliable. Converter-charger pair could be adapted for other power levels by changing transistor, diode, capacitor bank, and inductor.

  12. NASA Radioisotope Power Conversion Technology NRA Overview

    NASA Technical Reports Server (NTRS)

    Anderson, David J.

    2005-01-01

    The focus of the National Aeronautics and Space Administration's (NASA) Radioisotope Power Systems (RPS) Development program is aimed at developing nuclear power and technologies that would improve the effectiveness of space science missions. The Radioisotope Power Conversion Technology (RPCT) NASA Research Announcement (NRA) is an important mechanism through which research and technology activities are supported in the Advanced Power Conversion Research and Technology project of the Advanced Radioisotope Power Systems Development program. The purpose of the RPCT NRA is to advance the development of radioisotope power conversion technologies to provide higher efficiencies and specific powers than existing systems. These advances would enable a factor of two to four decrease in the amount of fuel and a reduction of waste heat required to generate electrical power, and thus could result in more cost effective science missions for NASA. The RPCT NRA selected advanced RPS power conversion technology research and development proposals in the following three areas: innovative RPS power conversion research, RPS power conversion technology development in a nominal 100 W(sub e) scale; and, milliwatt/multi-watt RPS (mWRPS) power conversion research. Ten RPCT NRA contracts were awarded in 2003 in the areas of Brayton, Stirling, thermoelectric (TE), and thermophotovoltaic (TPV) power conversion technologies. This paper will provide an overview of the RPCT NRA, a summary of the power conversion technologies approaches being pursued, and a brief digest of first year accomplishments.

  13. NASA Radioisotope Power Conversion Technology NRA Overview

    NASA Technical Reports Server (NTRS)

    Anderson, David J.

    2005-01-01

    The focus of the National Aeronautics and Space Administration s (NASA) Radioisotope Power Systems (RPS) Development program is aimed at developing nuclear power and technologies that would improve the effectiveness of space science missions. The Radioisotope Power Conversion Technology (RPCT) NASA Research Announcement (NRA) is an important mechanism through which research and technology activities are supported in the Advanced Power Conversion Research and Technology project of the Advanced Radioisotope Power Systems Development program. The purpose of the RPCT NRA is to advance the development of radioisotope power conversion technologies to provide higher efficiencies and specific powers than existing systems. These advances would enable a factor of 2 to 4 decrease in the amount of fuel and a reduction of waste heat required to generate electrical power, and thus could result in more cost effective science missions for NASA. The RPCT NRA selected advanced RPS power conversion technology research and development proposals in the following three areas: innovative RPS power conversion research, RPS power conversion technology development in a nominal 100We scale; and, milliwatt/multi-watt RPS (mWRPS) power conversion research. Ten RPCT NRA contracts were awarded in 2003 in the areas of Brayton, Stirling, thermoelectric (TE), and thermophotovoltaic (TPV) power conversion technologies. This paper will provide an overview of the RPCT NRA, a summary of the power conversion technologies approaches being pursued, and a brief digest of first year accomplishments.

  14. An Open System for Intravascular Ultrasound Imaging

    PubMed Central

    Qiu, Weibao; Chen, Yan; Li, Xiang; Yu, Yanyan; Cheng, Wang Fai; Tsang, Fu Keung; Zhou, Qifa; Shung, K. Kirk; Dai, Jiyan; Sun, Lei

    2013-01-01

    Visualization of the blood vessels can provide valuable morphological information for diagnosis and therapy strategies for cardiovascular disease. Intravascular ultrasound (IVUS) is able to delineate internal structures of vessel wall with fine spatial resolution. However, the developed IVUS is insufficient to identify the fibrous cap thickness and tissue composition of atherosclerotic lesions. Novel imaging strategies have been proposed, such as increasing the center frequency of ultrasound or using a modulated excitation technique to improve the accuracy of diagnosis. Dual-mode tomography combining IVUS with optical tomography has also been developed to determine tissue morphology and characteristics. The implementation of these new imaging methods requires an open system that allows users to customize the system for various studies. This paper presents the development of an IVUS system that has open structures to support various imaging strategies. The system design is based on electronic components and printed circuit board, and provides reconfigurable hardware implementation, programmable image processing algorithms, flexible imaging control, and raw RF data acquisition. In addition, the proposed IVUS system utilized a miniaturized ultrasound transducer constructed using PMN-PT single crystal for better piezoelectric constant and electromechanical coupling coefficient than traditional lead zirconate titanate (PZT) ceramics. Testing results showed that the IVUS system could offer a minimum detectable signal of 25 μV, allowing a 51 dB dynamic range at 47 dB gain, with a frequency range from 20 to 80 MHz. Finally, phantom imaging, in vitro IVUS vessel imaging, and multimodality imaging with photoacoustics were conducted to demonstrate the performance of the open system. PMID:23143570

  15. A Review of Intravascular Ultrasound–Based Multimodal Intravascular Imaging: The Synergistic Approach to Characterizing Vulnerable Plaques

    PubMed Central

    Ma, Teng; Zhou, Bill; Hsiai, Tzung K.; Shung, K. Kirk

    2015-01-01

    Catheter-based intravascular imaging modalities are being developed to visualize pathologies in coronary arteries, such as high-risk vulnerable atherosclerotic plaques known as thin-cap fibroatheroma, to guide therapeutic strategy at preventing heart attacks. Mounting evidences have shown three distinctive histopathological features—the presence of a thin fibrous cap, a lipid-rich necrotic core, and numerous infiltrating macrophages—are key markers of increased vulnerability in atherosclerotic plaques. To visualize these changes, the majority of catheter-based imaging modalities used intravascular ultrasound (IVUS) as the technical foundation and integrated emerging intravascular imaging techniques to enhance the characterization of vulnerable plaques. However, no current imaging technology is the unequivocal “gold standard” for the diagnosis of vulnerable atherosclerotic plaques. Each intravascular imaging technology possesses its own unique features that yield valuable information although encumbered by inherent limitations not seen in other modalities. In this context, the aim of this review is to discuss current scientific innovations, technical challenges, and prospective strategies in the development of IVUS-based multi-modality intravascular imaging systems aimed at assessing atherosclerotic plaque vulnerability. PMID:26400676

  16. Radioisotope thermoelectric generator cooling in the Shuttle bay

    NASA Technical Reports Server (NTRS)

    Stimpson, L. D.; Levine, D. I.

    1979-01-01

    The paper describes a Shuttle-integrated radioisotope thermoelectric generator (RTG) that consists primarily of a pump package and plumbing connected directly to the Shuttle payload heat exchanger. The RTG utilizes on-board water evaporative cooling capability, which is normally used for ascent, entry, and for supplementing the radiators. Attention is given to the RTG cooling concepts which include: (1) an active thermal cooling system (ATCS), where two Freon-21 loops operate simultaneously to transport heat from the Orbiter subsystem and payloads through liquid-to-liquid heat exchangers and pin-fin coldplates to four heat sinks, and (2) an atmosphere revitalization system (ARS) which provides for thermal, pressure, and contaminate control of the crew cabin and its equipment. The use of a payload heat exchanger to reduce weight, cost and complexity associated with an independent cooling system was investigated in detail.

  17. Management of cancer-associated disseminated intravascular coagulation.

    PubMed

    Levi, Marcel

    2016-04-01

    Cancer may be complicated by the occurrence of disseminated intravascular coagulation (DIC). DIC is characterized by a widespread and intravascular activation of coagulation (leading to intravascular fibrin deposition) and simultaneous consumption of coagulation factors and platelets (potentially resulting in bleeding). Clinically, DIC in cancer has in general a less fulminant presentation than the types of DIC complicating sepsis and trauma. A more gradual, but also more chronic, systemic activation of coagulation can proceed subclinically. Eventually this process may lead to exhaustion of platelets and coagulation factors and bleeding (for example at the site of the tumor) may be the first clinical symptom indicating the presence of DIC. In some cases, the clinical presentation of DIC in cancer may be reminiscent of thrombotic microangiopathies, which is understandable in view of the role of endothelium in both conditions. The therapeutic cornerstone of DIC is treatment of the underlying disorder but supportive treatment, specifically aimed at the hemostatic system may be required. PMID:27067981

  18. Monte Carol-Based Dosimetry of Beta-Emitters for Intravascular Brachytherapy

    SciTech Connect

    Choi, C.K.

    2002-06-25

    Monte Carlo simulations for radiation dosimetry and the experimental verifications of the simulations have been developed for the treatment geometry of intravascular brachytherapy, a form of radionuclide therapy for occluded coronary disease (restenosis). Monte Carlo code, MCNP4C, has been used to calculate the radiation dose from the encapsulated array of B-emitting seeds (Sr/Y-source train). Solid water phantoms have been fabricated to measure the dose on the radiochromic films that were exposed to the beta source train for both linear and curved coronary vessel geometries. While the dose difference for the 5-degree curved vessel at the prescription point of f+2.0 mm is within the 10% guideline set by the AAPM, however, the difference increased dramatically to 16.85% for the 10-degree case which requires additional adjustment for the acceptable dosimetry planning. The experimental dose measurements agree well with the simulation results

  19. Utilizing Radioisotope Power System Waste Heat for Spacecraft Thermal Management

    NASA Technical Reports Server (NTRS)

    Pantano, David R.; Dottore, Frank; Tobery, E. Wayne; Geng, Steven M.; Schreiber, Jeffrey G.; Palko, Joseph L.

    2005-01-01

    An advantage of using a Radioisotope Power System (RPS) for deep space or planetary surface missions is the readily available waste heat, which can be used for a number of beneficial purposes including: maintaining electronic components within a controlled temperature range, warming propulsion tanks and mobility actuators, and maintaining liquid propellants above their freezing temperature. Previous missions using Radioisotope Thermoelectric Generators (RTGs) dissipated large quantities of waste heat due to the low efficiency of the thermoelectric conversion technology. The next generation RPSs, such as the 110-Watt Stirling Radioisotope Generator (SRG110) will have higher conversion efficiencies, thereby rejecting less waste heat at a lower temperature and may require alternate approaches to transferring waste heat to the spacecraft. RTGs, with efficiencies of 6 to 7 percent, reject their waste heat at the relatively high heat rejection temperature of 200 C. This is an advantage when rejecting heat to space; however, transferring heat to the internal spacecraft components requires a large and heavy radiator heat exchanger. At the same time, sensitive spacecraft instruments must be shielded from the thermal radiation of the RTG. The SRG110, with an efficiency around 22 percent and 50 C nominal housing surface temperature, can readily transfer the available waste heat directly via heat pipes, thermal straps, or fluid loops. The lower temperatures associated with the SRG110 avoid the chances of overheating other scientific components, eliminating the need for thermal shields. This provides the spacecraft designers more flexibility when locating the generator for a specific mission. A common misconception with high-efficiency systems is that there is not enough waste heat for spacecraft thermal management. This paper will dispel this misconception and investigate the use of a high-efficiency SRG110 for spacecraft thermal management and outline potential methods of

  20. High Temperature Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    SciTech Connect

    Tarau, Calin; Walker, Kara L.; Anderson, William G.

    2009-03-16

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling converter provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) is under development to allow multiple stops and restarts of the Stirling engine. The status of the ongoing effort in developing this technology is presented in this paper. An earlier, preliminary design had a radiator outside the Advanced Stirling Radioisotope Generator (ASRG) casing, used NaK as the working fluid, and had the reservoir located on the cold side adapter flange. The revised design has an internal radiator inside the casing, with the reservoir embedded inside the insulation. A large set of advantages are offered by this new design. In addition to reducing the overall size and mass of the VCHP, simplicity, compactness and easiness in assembling the VCHP with the ASRG are significantly enhanced. Also, the permanently elevated temperatures of the entire VCHP allows the change of the working fluid from a binary compound (NaK) to single compound (Na). The latter, by its properties, allows higher performance and further mass reduction of the system. Preliminary design and analysis shows an acceptable peak temperature of the ASRG case of 140 deg. C while the heat losses caused by the addition of the VCHP are 1.8 W.

  1. 21 CFR 880.5970 - Percutaneous, implanted, long-term intravascular catheter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Percutaneous, implanted, long-term intravascular... and Personal Use Therapeutic Devices § 880.5970 Percutaneous, implanted, long-term intravascular catheter. (a) Identification. A percutaneous, implanted, long-term intravascular catheter is a device...

  2. Incidental Intravascular Lipoleiomyomatosis in A Hysterectomy Specimen: How To Manage?

    PubMed Central

    Aslanova, Rakhshanda; Can, Nuray; Okten, Sabri Berkem; Aslan, Mehmet Musa

    2015-01-01

    Leiomyomas are common benign tumors in female gynaecologic surgery. They are originated from smooth muscle cells of the uterus and/or sometimes of the uterine vessels. Intravascular lipoleiomyomatosis is a very rare form of leiomyomas which grow within veins and can extend up to vena cava inferior and right heart chamber with cardiac symptoms and is diagnosed by cardiovascular surgeons. We report a case of incidental intravascular lipoleiomyomatosis which was confined to the uterus being diagnosed after a total abdominal hysterectomy by pathology and its management strategy. PMID:25738043

  3. Current concepts in the management of disseminated intravascular coagulation.

    PubMed

    Thachil, Jecko; Toh, Cheng Hock

    2012-04-01

    Disseminated Intravascular Coagulation is a clinicopathological syndrome where widespread intravascular coagulation occurs in response to an inciting process. The pathophysiology for this disorder is complex with an important role for thrombin, the central regulator of the coagulation process. Since the clinical spectrum of DIC is variable due to its dynamic nature, the laboratory diagnosis should ideally be not based on a single marker or an isolated set of results. The treatment should primary focus on the management of the underlying triggering condition with blood products used as resuscitative measures. Newer therapeutic modalities have been recently tried with success although the management of DIC still remains a major challenge.

  4. Incidence of intravascular penetration in transforaminal cervical epidural steroid injections.

    PubMed

    Furman, Michael B; Giovanniello, Michael T; O'Brien, Erin M

    2003-01-01

    STUDY DESIGN A prospective, observational, human, study was conducted. OBJECTIVES To evaluate the incidence of vascular penetration during fluoroscopically guided, contrast-enhanced transforaminal cervical epidural steroid injections, and to determine whether the observation of blood in the needle hub can be used to predict a vascular injection. SUMMARY OF BACKGROUND DATA Incorrectly placed intravascular cervical spinal injections result in medication flow systemically and not to the desired target. A recently published study demonstrates a high incidence of intravascular injections in transforaminal lumbosacral epidural injections. No studies so far have evaluated the incidence of vascular injections in transforaminal cervical epidural steroid injections, nor have they calculated the ability of observed blood in the needle hub to predict a vascular injection in the cervical spine.METHODS The incidence of fluoroscopically confirmed intravascular uptake of contrast was prospectively observed in 337 patients treated with cervical transforaminal epidural steroid injections. The ability of observed blood in the needle hub to predict intravascular injection was also investigated. For each subject, the injection level was chosen on the basis of the clinical scenario including history, physical examination, and review of imaging studies. Some patients had multilevel injections. Using fluoroscopic guidance, the authors placed a 25-gauge needle into the epidural space using a transforaminal approach according to accepted standard technique. Needle tip location was confirmed with biplanar imaging. The presence or absence of blood in the needle hub spontaneously ("flash") and after attempted aspiration by pulling back on the syringe's plunger was documented. Contrast then was injected under real-time fluoroscopy to determine whether the location of the needle tip was intravascular. The results were recorded in a prospective manner indicating the presence or absence of blood

  5. Advanced Stirling Radioisotope Generator Life Certification Plan

    NASA Technical Reports Server (NTRS)

    Rusick, Jeffrey J.; Zampino, Edward

    2013-01-01

    An Advanced Stirling Radioisotope Generator (ASRG) power supply is being developed by the Department of Energy (DOE) in partnership with NASA for potential future deep space science missions. Unlike previous radioisotope power supplies for space exploration, such as the passive MMRTG used recently on the Mars Curiosity rover, the ASRG is an active dynamic power supply with moving Stirling engine mechanical components. Due to the long life requirement of 17 years and the dynamic nature of the Stirling engine, the ASRG project faced some unique challenges trying to establish full confidence that the power supply will function reliably over the mission life. These unique challenges resulted in the development of an overall life certification plan that emphasizes long-term Stirling engine test and inspection when analysis is not practical. The ASRG life certification plan developed is described.

  6. Reactors are indispensable for radioisotope production.

    PubMed

    Mushtaq, Ahmad

    2010-12-01

    Radioisotopes can be produced by reactors and accelerators. For certain isotopes there could be an advantage to a certain production method. However, nowadays many reports suggest, that useful isotopes needed in medicine, industry and research could be produced efficiently and dependence on reactors using enriched U-235 may be eliminated. In my view reactors and accelerators will continue to play their role side by side in the supply of suitable and economical sources of isotopes.

  7. Light-weight radioisotope heater unit

    SciTech Connect

    Schock, A.

    1981-01-01

    DOE is developing a new generation of radioisotope-fueled 1-watt heaters, for initial use on NASA's Galileo and International Solar-Polar Missions. Each heater must contain passive safety provisions to ensure fuel retention under all credible accident conditions. Initial design reviews raised some concern about the accuracy of the predicted peak reentry temperature, and about the adequacy of the safety margin under certain unlike reentry modes. 5 refs.

  8. NEW DIRECTIONS IN RADIOISOTOPE SPECTRUM IDENTIFICATION

    SciTech Connect

    Salaymeh, S.; Jeffcoat, R.

    2010-06-17

    Recent studies have found the performance of commercial handheld detectors with automatic RIID software to be less than acceptable. Previously, we have explored approaches rooted in speech processing such as cepstral features and information-theoretic measures. Scientific advances are often made when researchers identify mathematical or physical commonalities between different fields and are able to apply mature techniques or algorithms developed in one field to another field which shares some of the same challenges. The authors of this paper have identified similarities between the unsolved problems faced in gamma-spectroscopy for automated radioisotope identification and the challenges of the much larger body of research in speech processing. Our research has led to a probabilistic framework for describing and solving radioisotope identification problems. Many heuristic approaches to classification in current use, including for radioisotope classification, make implicit probabilistic assumptions which are not clear to the users and, if stated explicitly, might not be considered desirable. Our framework leads to a classification approach with demonstrable improvements using standard feature sets on proof-of-concept simulated and field-collected data.

  9. Quantitation of renal function using radioisotopic techniques.

    PubMed

    O'Malley, J P; Ziessman, H A

    1993-03-01

    Radioisotopic methods are practical for clinical use because they do not require continuous intravenous infusion or urine collection. This obviously is of great advantage in infants and small children, in whom accurate urine collection is difficult, but the techniques apply to adults as well. The ability to determine individual kidney function is a major benefit. Accuracies of the radioisotopic techniques vary but generally are within clinically acceptable ranges. The need for accuracy and reproducibility can be balanced with the desire for speed and convenience when choosing among the different techniques. Methods that use plasma sampling provide greater accuracy and are recommended in cases of severe dysfunction, whereas methods such as Gates' camera method, which eliminates plasma samples, can be completed in minutes. Radioisotopic techniques are most useful in the ranges of mild to moderately decreased function, in which serum creatinine concentration is nondiagnostic, and although they are much less accurate at markedly low renal function levels, so is 24-hour creatinine clearance. In conclusion, radiopharmaceutical agents offer a wide array of possible techniques for simple, accurate, and noninvasive measurement of global as well as individual GFR and ERPF. PMID:8462269

  10. Small radioisotope thermophotovoltaic (RTPV) generators

    NASA Astrophysics Data System (ADS)

    Schock, A.; Or, C.; Kumar, V.

    1996-02-01

    The National Aeronautics and Space Administration's recently inaugurated New Millennium program, with its emphasis on miniaturized spacecraft, has generated interest in a low-power (10- to 30-watt), low-mass, high-efficiency RTPV power system. This led to a Department of Energy (DOE)-sponsored design study by OSC (formerly Fairchild) personnel, who had previously conducted very encouraging studies of 75-watt RTPV systems based on two 250-watt General Purpose Heat Source (GPHS) modules. Since these modules were too large for the small RTPVs described in this paper, OSC generated derivative designs for 125-watt and 62.5-watt heat source modules. To minimize the need for new development and safety verification studies, these contained identical fuel pellets, clads, impact shell, and thermal insulation as the previously developed and safety-qualified 250-watt units. OSC also generated a novel heat source support scheme to reduce the heat losses through the structural supports, and a new and much simpler radiator structure, employing no honeycombs or heat pipes. OSC's previous RTPV study had been based on the use of GaSb PV cells and spectrally selective Infra-Red (IR) filters that had been partially developed and characterized by Boeing (now EDTEK) personnel. The present study was based on greatly improved selective filters developed and performance-mapped by EDTEK under an OSC-initiated subcontract. The paper describes illustrative small-RTPV designs and analyzes their mass, size, power output, system efficiency, and specific power, and illustrates their integration with a miniaturized New Millennium spacecraft.

  11. A Prognostic Dilemma of Basal Cell Carcinoma with Intravascular Invasion

    PubMed Central

    Niumsawatt, Vachara; Castley, Andrew

    2016-01-01

    Summary: Basal cell carcinoma is the most common malignancy; however, it very rarely metastasizes. Despite the low mortality caused by this cancer, once it spreads, it has dim prognosis. We report a case of basal cell carcinoma with rare intravascular invasion and review the literature for risk factors and management of metastasis.

  12. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cardiovascular intravascular filter. 870.3375 Section 870.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... side of the heart and the pulmonary circulation. (b) Classification. Class II. The special controls...

  13. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cardiovascular intravascular filter. 870.3375 Section 870.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... side of the heart and the pulmonary circulation. (b) Classification. Class II. The special controls...

  14. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cardiovascular intravascular filter. 870.3375 Section 870.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices §...

  15. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiovascular intravascular filter. 870.3375 Section 870.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices §...

  16. Intravascular Ultrasound and Virtual Histology of Basilar Artery Atherosclerotic Lesion

    PubMed Central

    López-Rueda, A.; González García, A.; Aguilar Pérez, M.; Gutiérrez Jarrín, R.K.; Mayol Deyá, A.

    2011-01-01

    Summary To our knowledge, this paper presents the first intravascular ultrasound and virtual histology (IVUS-VH) study in the basilar artery. IVUS-VH serves to characterize and determine the extension of the plaque and we also to check stent placement. PMID:22192552

  17. Stirling Convertor Technologies Being Developed for a Stirling Radioisotope Generator

    NASA Technical Reports Server (NTRS)

    Thieme, Lanny G.

    2003-01-01

    The Department of Energy, Lockheed Martin, Stirling Technology Company (STC), and the NASA Glenn Research Center are developing a high-efficiency Stirling Radioisotope Generator (SRG) for NASA space science missions. The SRG is being developed for multimission use, including providing electric power for unmanned Mars rovers and deep space missions. On Mars, rovers with SRGs would be used for missions that might not be able to use photovoltaic power systems, such as exploration at high Martian latitudes and missions of long duration. The projected SRG system efficiency of 23 percent will reduce the required amount of radioisotope by a factor of 4 or more in comparison to currently used Radioisotope Thermoelectric Generators. The Department of Energy recently named Lockheed Martin as the system integration contractor. Lockheed Martin has begun to develop the SRG engineering unit under contract to the Department of Energy, and has contract options to develop the qualification unit and the first flight units. The developers expect the SRG to produce about 114 Wdc at the beginning of mission, using two opposed Stirling convertors and two General Purpose Heat Source modules. STC previously developed the Stirling convertor under contract to the Department of Energy and is now providing further development as a subcontractor to Lockheed Martin. Glenn is conducting an in-house technology project to assist in developing the convertor for space qualification and mission implementation. A key milestone was recently reached with the accumulation of 12 000 hr of long-term aging on two types of neodymium-iron boron permanent magnets. These tests are characterizing any possible aging in the strength or demagnetization resistance of the magnets used in the linear alternator. Preparations are underway for a thermal/vacuum system demonstration and unattended operation during endurance testing of the 55-We Technology Demonstration Convertors. In addition, Glenn is developing a

  18. INTRACORPOREAL HEAT DISSIPATION FROM A RADIOISOTOPE-POWERED ARTIFICIAL HEART.

    PubMed

    Huffman, Fred N.; Hagen, Kenneth G.; Whalen, Robert L.; Fuqua, John M.; Norman, John C.

    1974-01-01

    The feasibility of radioisotope-fueled circulatory support systems depends on the ability of the body to dissipate the reject heat from the power source driving the blood pump as well as to tolerate chronic intracorporeal radiation. Our studies have focused on the use of the circulating blood as a heat sink. Initial in vivo heat transfer studies utilized straight tube heat exchangers (electrically and radioisotope energized) to replace a segment of the descending aorta. More recent studies have used a left ventricular assist pump as a blood-cooled heat exchanger. This approach minimizes trauma, does not increase the area of prosthetic interface with the blood, and minimizes system volume. Heat rejected from the thermal engine (vapor or gas cycle) is transported from the nuclear power source in the abdomen to the pump in the thoracic cavity via hydraulic lines. Adjacent tissue is protected from the fuel capsule temperature (900 to 1200 degrees F) by vacuum foil insulation and polyurethane foam. The in vivo thermal management problems have been studied using a simulated thermal system (STS) which approximates the heat rejection and thermal transport mechanisms of the nuclear circulatory support systems under development by NHLI. Electric heaters simulate the reject heat from the thermal engines. These studies have been essential in establishing the location, suspension, surgical procedures, and postoperative care for implanting prototype nuclear heart assist systems in calves. The pump has a thermal impedance of 0.12 degrees C/watt. Analysis of the STS data in terms of an electrical analog model implies a heat transfer coefficient of 4.7 x 10(-3) watt/cm(2) degrees C in the abdomen compared to a value of 14.9 x 10(-3) watt/cm(2) degrees C from the heat exchanger plenum into the diaphragm.

  19. INTRACORPOREAL HEAT DISSIPATION FROM A RADIOISOTOPE-POWERED ARTIFICIAL HEART

    PubMed Central

    Huffman, Fred N.; Hagen, Kenneth G.; Whalen, Robert L.; Fuqua, John M.; Norman, John C.

    1974-01-01

    The feasibility of radioisotope-fueled circulatory support systems depends on the ability of the body to dissipate the reject heat from the power source driving the blood pump as well as to tolerate chronic intracorporeal radiation. Our studies have focused on the use of the circulating blood as a heat sink. Initial in vivo heat transfer studies utilized straight tube heat exchangers (electrically and radioisotope energized) to replace a segment of the descending aorta. More recent studies have used a left ventricular assist pump as a blood-cooled heat exchanger. This approach minimizes trauma, does not increase the area of prosthetic interface with the blood, and minimizes system volume. Heat rejected from the thermal engine (vapor or gas cycle) is transported from the nuclear power source in the abdomen to the pump in the thoracic cavity via hydraulic lines. Adjacent tissue is protected from the fuel capsule temperature (900 to 1200°F) by vacuum foil insulation and polyurethane foam. The in vivo thermal management problems have been studied using a simulated thermal system (STS) which approximates the heat rejection and thermal transport mechanisms of the nuclear circulatory support systems under development by NHLI. Electric heaters simulate the reject heat from the thermal engines. These studies have been essential in establishing the location, suspension, surgical procedures, and postoperative care for implanting prototype nuclear heart assist systems in calves. The pump has a thermal impedance of 0.12°C/watt. Analysis of the STS data in terms of an electrical analog model implies a heat transfer coefficient of 4.7 × 10−3 watt/cm2°C in the abdomen compared to a value of 14.9 × 10−3 watt/cm2°C from the heat exchanger plenum into the diaphragm. Images PMID:15215968

  20. Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    NASA Astrophysics Data System (ADS)

    Anderson, William G.; Tarau, Calin

    2008-01-01

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling convertor provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) was designed to allow multiple stops and restarts of the Stirling engine. A VCHP was designed for the Advanced Stirling Radioisotope Generator, with a 850 °C heater head temperature. The VCHP turns on with a ΔT of 30 °C, which is high enough to not risk standard ASRG operation but low enough to save most heater head life. This VCHP has a low mass, and low thermal losses for normal operation. In addition to the design, a proof-of-concept NaK VCHP was fabricated and tested. While NaK is normally not used in heat pipes, it has an advantage in that it is liquid at the reservoir operating temperature, while Na or K alone would freeze. The VCHP had two condensers, one simulating the heater head, and the other simulating the radiator. The experiments successfully demonstrated operation with the simulated heater head condenser off and on, while allowing the reservoir temperature to vary over 40 to 120 °C, the maximum range expected. In agreement with previous NaK heat pipe tests, the evaporator ΔT was roughly 70 °C, due to distillation of the NaK in the evaporator.

  1. Pathway of radioisotopes from land surface to sewage sludge

    NASA Astrophysics Data System (ADS)

    Fischer, Helmut W.; Yokoo, Yoshiyuki

    2014-05-01

    Radioactive surface contaminations will only partially remain at the original location - a fraction of the inventory will take part in (mainly terrestrial and aquatic) environmental transport processes. The probably best known and most important process comprises the food chain. Besides, the translocation of dissolved and particle-bound radioisotopes with surface waters plays an important role. These processes can have the effect of displacing large radioisotope amounts over considerable distances and of creating new sinks and hot spots, as it is already known for sewage sludge. We are reporting on a combined modeling and experimental project concerning the transport of I-131 and Cs-134/Cs-137 FDNPP 2011 depositions in the Fukushima Prefecture. Well-documented experimental data sets are available for surface deposition and sewage sludge concentrations. The goal is to model the pathway in between, involving surface runoff, transport in the sewer system and processes in the sewage treatment plant. Watershed runoff and sewer transport will be treated with models developed recently by us in other projects. For sewage treatment processes a new model is currently being constructed. For comparison and further validation, historical data from Chernobyl depositions and tracer data from natural and artificial, e.g. medical, isotopes will be used. First results for 2011 data from Fukushima Prefecture will be presented. The benefits of the study are expected to be two-fold: on one hand, the abundant recent and historical data will help to develop and improve environmental transport models; on the other hand, both data and models will help in identifying the most critical points in the envisaged transport pathways in terms of radiation protection and waste management.

  2. Markets for reactor-produced non-fission radioisotopes

    SciTech Connect

    Bennett, R.G.

    1995-01-01

    Current market segments for reactor produced radioisotopes are developed and reported from a review of current literature. Specific radioisotopes studied in is report are the primarily selected from those with major medical or industrial markets, or those expected to have strongly emerging markets. Relative market sizes are indicated. Special emphasis is given to those radioisotopes that are best matched to production in high flux reactors such as the Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory or the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory. A general bibliography of medical and industrial radioisotope applications, trends, and historical notes is included.

  3. Vitrified chemically bonded phosphate ceramics for immobilization of radioisotopes

    DOEpatents

    Wagh, Arun S.

    2016-04-05

    A method of immobilizing a radioisotope and vitrified chemically bonded phosphate ceramic (CBPC) articles formed by the method are described. The method comprises combining a radioisotope-containing material, MgO, a source of phosphate, and optionally, a reducing agent, in water at a temperature of less than 100.degree. C. to form a slurry; curing the slurry to form a solid intermediate CBPC article comprising the radioisotope therefrom; comminuting the intermediate CBPC article, mixing the comminuted material with glass frits, and heating the mixture at a temperature in the range of about 900 to about 1500.degree. C. to form a vitrified CBPC article comprising the radioisotope immobilized therein.

  4. Pharmacokinetics of Intravascularly Administered (65)Zinc in Channel Catfish (Ictalurus punctatus)

    SciTech Connect

    Barron, Mace G.; Schultz, Irvin R. ); Newman, Michael E.

    1999-12-01

    We compared the pharmacokinetics of the radioisotope 65Zinc (65Zn) in blood, plasma, and whole body of adult channel catfish (Ictalurus punctatus) following intravascular (iv) administration. A two compartment model described the pharmacokinetics of 65Zn in plasma and blood during the first 40 days following iv administration, but was unable to describe the long-term disposition of 65Zn. Whole body counting revealed that approximately half of the 65Zn dose was sequestered in a slowly exchangeable pool with a half-life of 1.5 years. Greater than 99% of the circulating 65Zn was bound to plasma proteins, whereas there was less than 1% binding to red blood cells. Synthesis of the results for channel catfish and existing data in other species indicates three phases in the pharmacokinetics of zinc. The first phase consists of initial distribution outside the vascular system to kidney, liver, and other organs (alpha phase in blood and plasma; t1/2 of 4 to 5 hours). The second phase involves distribution from organs to a slowly exchangeable zinc pool, likely consisting of bone (beta phase in blood and plasma; alpha phase in whole body; t1/2 of 4 to 20 days). The third phase appears to involve a slow turnover of sequestered zinc (t1/2 greater than 1 year). Blood sampling or short-term whole body measurements will underestimate the persistence of zinc in fish, thus prolonged sampling and measurement of whole body concentrations are necessary to characterize the pharmacokinetics of zinc.

  5. The Copper Radioisotopes: A Systematic Review with Special Interest to 64Cu

    PubMed Central

    Niccoli Asabella, Artor; Cascini, Giuseppe Lucio; Altini, Corinna; Paparella, Domenico; Notaristefano, Antonio

    2014-01-01

    Copper (Cu) is an important trace element in humans; it plays a role as a cofactor for numerous enzymes and other proteins crucial for respiration, iron transport, metabolism, cell growth, and hemostasis. Natural copper comprises two stable isotopes, 63Cu and 65Cu, and 5 principal radioisotopes for molecular imaging applications (60Cu, 61Cu, 62Cu, and 64Cu) and in vivo targeted radiation therapy (64Cu and 67Cu). The two potential ways to produce Cu radioisotopes concern the use of the cyclotron or the reactor. A noncopper target is used to produce noncarrier-added Cu thanks to a chemical separation from the target material using ion exchange chromatography achieving a high amount of radioactivity with the lowest possible amount of nonradioactive isotopes. In recent years, Cu isotopes have been linked to antibodies, proteins, peptides, and nanoparticles for preclinical and clinical research; pathological conditions that influence Cu metabolism such as Menkes syndrome, Wilson disease, inflammation, tumor growth, metastasis, angiogenesis, and drug resistance have been studied. We aim to discuss all Cu radioisotopes application focusing on 64Cu and in particular its form 64CuCl2 that seems to be the most promising for its half-life, radiation emissions, and stability with chelators, allowing several applications in oncological and nononcological fields. PMID:24895611

  6. The copper radioisotopes: a systematic review with special interest to 64Cu.

    PubMed

    Niccoli Asabella, Artor; Cascini, Giuseppe Lucio; Altini, Corinna; Paparella, Domenico; Notaristefano, Antonio; Rubini, Giuseppe

    2014-01-01

    Copper (Cu) is an important trace element in humans; it plays a role as a cofactor for numerous enzymes and other proteins crucial for respiration, iron transport, metabolism, cell growth, and hemostasis. Natural copper comprises two stable isotopes, (63)Cu and (65)Cu, and 5 principal radioisotopes for molecular imaging applications ((60)Cu, (61)Cu, (62)Cu, and (64)Cu) and in vivo targeted radiation therapy ((64)Cu and (67)Cu). The two potential ways to produce Cu radioisotopes concern the use of the cyclotron or the reactor. A noncopper target is used to produce noncarrier-added Cu thanks to a chemical separation from the target material using ion exchange chromatography achieving a high amount of radioactivity with the lowest possible amount of nonradioactive isotopes. In recent years, Cu isotopes have been linked to antibodies, proteins, peptides, and nanoparticles for preclinical and clinical research; pathological conditions that influence Cu metabolism such as Menkes syndrome, Wilson disease, inflammation, tumor growth, metastasis, angiogenesis, and drug resistance have been studied. We aim to discuss all Cu radioisotopes application focusing on (64)Cu and in particular its form (64)CuCl2 that seems to be the most promising for its half-life, radiation emissions, and stability with chelators, allowing several applications in oncological and nononcological fields.

  7. Miniaturized radioisotope solid state power sources

    NASA Astrophysics Data System (ADS)

    Fleurial, J.-P.; Snyder, G. J.; Patel, J.; Herman, J. A.; Caillat, T.; Nesmith, B.; Kolawa, E. A.

    2000-01-01

    Electrical power requirements for the next generation of deep space missions cover a wide range from the kilowatt to the milliwatt. Several of these missions call for the development of compact, low weight, long life, rugged power sources capable of delivering a few milliwatts up to a couple of watts while operating in harsh environments. Advanced solid state thermoelectric microdevices combined with radioisotope heat sources and energy storage devices such as capacitors are ideally suited for these applications. By making use of macroscopic film technology, microgenrators operating across relatively small temperature differences can be conceptualized for a variety of high heat flux or low heat flux heat source configurations. Moreover, by shrinking the size of the thermoelements and increasing their number to several thousands in a single structure, these devices can generate high voltages even at low power outputs that are more compatible with electronic components. Because the miniaturization of state-of-the-art thermoelectric module technology based on Bi2Te3 alloys is limited due to mechanical and manufacturing constraints, we are developing novel microdevices using integrated-circuit type fabrication processes, electrochemical deposition techniques and high thermal conductivity substrate materials. One power source concept is based on several thermoelectric microgenerator modules that are tightly integrated with a 1.1W Radioisotope Heater Unit. Such a system could deliver up to 50mW of electrical power in a small lightweight package of approximately 50 to 60g and 30cm3. An even higher degree of miniaturization and high specific power values (mW/mm3) can be obtained when considering the potential use of radioisotope materials for an alpha-voltaic or a hybrid thermoelectric/alpha-voltaic power source. Some of the technical challenges associated with these concepts are discussed in this paper. .

  8. Medical Radioisotope Data Survey: 2002 Preliminary Results

    SciTech Connect

    Siciliano, Edward R.

    2004-06-23

    A limited, but accurate amount of detailed information about the radioactive isotopes used in the U.S. for medical procedures was collected from a local hospital and from a recent report on the U.S. Radiopharmaceutical Markets. These data included the total number of procedures, the specific types of procedures, the specific radioisotopes used in these procedures, and the dosage administered per procedure. The information from these sources was compiled, assessed, pruned, and then merged into a single, comprehensive and consistent set of results presented in this report. (PIET-43471-TM-197)

  9. Cooling radioisotope thermoelectric generators in the Shuttle

    NASA Technical Reports Server (NTRS)

    Norman, R. M.

    1978-01-01

    Radioisotope thermoelectric generators (RTG) to be used on future spacecraft and launched by the Shuttle must be cooled from the time they are installed and enclosed until the spacecraft is deployed from the Shuttle. A special Cooling Kit maintains their temperature well below critical by circulating water through the coils soldered to them and through a heat exchanger that boils water and externally discharges the resulting steam. The RTG Cooling Kit, including its support frame, if fully charged with about 64 kg of evaporation water, will increase the Shuttle launch mass by about 200 kg.

  10. Radioisotope thermoelectric generator transport trailer system

    SciTech Connect

    Ard, K.E.; King, D.A.; Leigh, H.; Satoh, J.A.

    1995-01-20

    The Radioisotope Thermoelectric Generator (RTG) Transportation System, designated as System 100, comprises four major systems. The four major systems are designated as the Packaging System (System 120), Trailer System (System 140), Operations and Ancillary Equipment System (System 160), and Shipping and Receiving Facility Transport System (System 180). Packaging System (System 120), including the RTG packaging is licensed (regulatory) hardware; it is certified by the U.S. Department of Energy to be in accordance with Title 10, {ital Code} {ital of} {ital Federal} {ital Regulations}, Part 71 (10 CFR 71). System 140, System 160, and System 180 are nonlicensed (nonregulatory) hardware. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}

  11. Characterization of coronary atherosclerosis by intravascular imaging modalities.

    PubMed

    Honda, Satoshi; Kataoka, Yu; Kanaya, Tomoaki; Noguchi, Teruo; Ogawa, Hisao; Yasuda, Satoshi

    2016-08-01

    Coronary artery disease (CAD) is highly prevalent in Western countries and is associated with morbidity, mortality, and a significant economic burden. Despite the development of anti-atherosclerotic medical therapies, many patients still continue to suffer from coronary events. This residual risk indicates the need for better risk stratification and additional therapies to achieve more reductions in cardiovascular risk. Recent advances in imaging modalities have contributed to visualizing atherosclerotic plaques and defining lesion characteristics in vivo. This innovation has been applied to refining revascularization procedure, assessment of anti-atherosclerotic drug efficacy and the detection of high-risk plaques. As such, intravascular imaging plays an important role in further improvement of cardiovascular outcomes in patients with CAD. The current article reviews available intravascular imaging modalities with regard to its method, advantage and disadvantage. PMID:27500094

  12. Disseminated intravascular coagulation in term and preterm neonates.

    PubMed

    Veldman, Alex; Fischer, Doris; Nold, Marcel F; Wong, Flora Y

    2010-06-01

    Among critically ill patients, the risk of developing disseminated intravascular coagulation (DIC) is probably highest in neonates. Low plasma reserves in pro- and anticoagulant coagulation factors, intravascular volume contraction after birth, and a high incidence of hypoxia and sepsis in critically ill newborns rapidly lead to a decompensation of the coagulation system in this population. Global coagulation tests and single-factor plasma levels have to be interpreted in the context of age-corrected normal ranges. Platelet consumption and reduced protein C plasma levels have diagnostic value; the latter also has prognostic potential in neonates with DIC and sepsis. Therapeutic success relies heavily on reversal of the underlying condition. Some coagulation-specific therapies have been explored in small studies and case series with varying success and sometimes conflicting results. Therefore, larger controlled trials in this common and serious condition are urgently needed.

  13. Intravascular photoacoustic tomography for characterization of atherosclerotic lipid and inflammation

    NASA Astrophysics Data System (ADS)

    Zhang, Jian; Qin, Huan; Shi, Yujiao; Yang, Sihua; Xing, Da

    2014-09-01

    Photoacoustic imaging is a fast growing imaging technology depending on its high optical resolution of optics while taking the advantage of the high penetration depth of ultrasound. In this paper, we demonstrate the new progress in the photoacoustic imaging. Atherosclerosis is characterized by a progressive build-up of lipid in the arterial wall, which is known as plaque. Histological studies demonstrate that the primary cause of acute cardiovascular events is the rupture of atherosclerotic plaques. Lipid and inflammation within the plaque are related to influence the propensity of plaques to disrupt. Photoacoustic intravascular tomography (IVPAT) holds a great advantage in providing comprehensive morphological and functional information of plaques. Lipid relative concentration maps of atherosclerotic aorta were obtained and compared with histology. Furthermore, by selectively targeting the intravascular inflammatory cytokines, IVPAT is also capable of mapping the inflamed area and determining the degree of inflammation.

  14. Integrated intravascular optical coherence tomography ultrasound imaging system

    NASA Astrophysics Data System (ADS)

    Yin, Jiechen; Yang, Hao-Chung; Li, Xiang; Zhang, Jun; Zhou, Qifa; Hu, Changhong; Shung, K. Kirk; Chen, Zhongping

    2010-01-01

    We report on a dual-modality optical coherence tomography (OCT) ultrasound (US) system for intravascular imaging. To the best of our knowledge, we have developed the first integrated OCT-US probe that combines OCT optical components with an US transducer. The OCT optical components mainly consist of a single-mode fiber, a gradient index lens for light-beam focusing, and a right-angled prism for reflecting light into biological tissue. A 40-MHz piezoelectric transducer (PZT-5H) side-viewing US transducer was fabricated to obtain the US image. These components were integrated into a single probe, enabling both OCT and US imaging at the same time. In vitro OCT and ultrasound images of a rabbit aorta were obtained using this dual-modality imaging system. This study demonstrates the feasibility of an OCT-US system for intravascular imaging, which is expected to have a prominent impact on early detection and characterization of atherosclerosis.

  15. Characterization of coronary atherosclerosis by intravascular imaging modalities

    PubMed Central

    Honda, Satoshi; Kanaya, Tomoaki; Noguchi, Teruo; Ogawa, Hisao; Yasuda, Satoshi

    2016-01-01

    Coronary artery disease (CAD) is highly prevalent in Western countries and is associated with morbidity, mortality, and a significant economic burden. Despite the development of anti-atherosclerotic medical therapies, many patients still continue to suffer from coronary events. This residual risk indicates the need for better risk stratification and additional therapies to achieve more reductions in cardiovascular risk. Recent advances in imaging modalities have contributed to visualizing atherosclerotic plaques and defining lesion characteristics in vivo. This innovation has been applied to refining revascularization procedure, assessment of anti-atherosclerotic drug efficacy and the detection of high-risk plaques. As such, intravascular imaging plays an important role in further improvement of cardiovascular outcomes in patients with CAD. The current article reviews available intravascular imaging modalities with regard to its method, advantage and disadvantage. PMID:27500094

  16. NASA Radioisotope Power Systems Program Update

    NASA Astrophysics Data System (ADS)

    Harmon, B. Alan; Lavery, David B.

    2008-01-01

    The use of Radioisotope Power Systems (RPS) represents a critical capability for exploration of the Solar System. RPS have been used for decades to power deep space missions and sometimes for the operation of landers or rovers on Mars. Modest power needs (<~1 KWe) for regions relatively far from the Sun (~>5 AU) make them attractive, and, in most cases, essential for a variety of missions. Even close by, such as on the surface of the Moon or Mars, RPS enhances operational capability. NASA's strategic planning now contemplates more ambitious missions than those of the past, with the likelihood of increasingly severe or more diverse environments in which to contend. We are at a crossroads in the application of radioisotope power, thanks partially to progress made, but also due to the realities of budget constraints and the availability of plutonium-238 fuel. Within a few years, investments in power conversion technologies could yield next generation flight systems with capability for multiple environments, and improved efficiency and specific power. However, for RPS, given the demands on reliability and system longevity (15+years), infusion of any new RPS technology is the challenge. We review progress made during the past year in development of RPS and note applications in NASA's Science Plan (2007).

  17. Reliability Issues in Stirling Radioisotope Power Systems

    NASA Technical Reports Server (NTRS)

    Shah, Ashwin R.; Schreiber, Jeffrey G.

    2004-01-01

    Stirling power conversion is a potential candidate for use in a Radioisotope Power System (RPS) for space science missions because it offers a multifold increase in the conversion efficiency of heat to electric power and reduced requirement of radioactive material. Reliability of an RPS that utilizes Stirling power conversion technology is important in order to ascertain long term successful performance. Owing to long life time requirement (14 years), it is difficult to perform long-term tests that encompass all the uncertainties involved in the design variables of components and subsystems comprising the RPS. The requirement for uninterrupted performance reliability and related issues are discussed, and some of the critical areas of concern are identified. An overview of the current on-going efforts to understand component life, design variables at the component and system levels, and related sources and nature of uncertainties are also discussed. Current status of the 110 watt Stirling Radioisotope Generator (SRG110) reliability efforts is described. Additionally, an approach showing the use of past experience on other successfully used power systems to develop a reliability plan for the SRG110 design is outlined.

  18. Rhenium Radioisotopes for Therapeutic Radiopharmaceutical Development

    SciTech Connect

    Beets, A.L.; Knapp, F.F., Jr.; Kropp, J.; Lin, W.-Y.; Pinkert, J.; Wang, S.-Y.

    1999-01-18

    The availability of therapeutic radioisotopes at reasonable costs is important for applications in nuclear medicine, oncology and interventional cardiology, Rhenium-186 (Re-186) and rhenium-1 88 (Re-188) are two reactor-produced radioisotope which are attractive for a variety of therapeutic applications, Rhenium-186 has a half-life of 90 hours and decays with emission of a &particle with a maximum energy of 1.08 MeV and a 135 keV (9Yo) gamma which permits imaging. In contrast, Re- 188 has a much shorter half-life of 16.9 hours and emits a p-particle with a much higher energy of 2.12 MeV (Em=) and a 155 keV gamma photon (15Yo) for imaging. While Re-186 is unavailable from a generator system and must be directly produced in a nuclear reactor, Re-188 can also be directly produced in a reactor with high specific activity, but is more conveniently and cost-effectively available as carrier-free sodium perrhenate by saline elution of the alumina-based tungsten-188 (W1 88)/Re-l 88 generator system [1-2]. Since a comprehensive overviewofRe-186 and Re-188 therapeutic agents is beyond the scope of this &tended Abstrac4 the goal is to provide key examples of various agents currently in clinical use and those which are being developed for important clinical applications.

  19. Preparing for Harvesting Radioisotopes from FRIB

    SciTech Connect

    Peaslee, Graham F.; Lapi, Suzanne E.

    2015-02-02

    The Facility for Rare Isotope Beams (FRIB) is the next generation accelerator facility under construction at Michigan State University. FRIB will produce a wide variety of rare isotopes by a process called projectile fragmentation for a broad range of new experiments when it comes online in 2020. The accelerated rare isotope beams produced in this facility will be more intense than any current facility in the world - in many cases by more than 1000-fold. These beams will be available to the primary users of FRIB in order to do exciting new fundamental research with accelerated heavy ions. In the standard mode of operation, this will mean one radioisotope will be selected at a time for the user. However, the projectile fragmentation process also yields hundreds of other radioisotopes at these bombarding energies, and many of these rare isotopes are long-lived and could have practical applications in medicine, national security or the environment. This project developed new methods to collect these long-lived rare isotopes that are by-products of the standard FRIB operation. These isotopes are important to many areas of research, thus this project will have a broad impact in several scientific areas including medicine, environment and homeland security.

  20. Cosmogenic radioisotopes in Gebel Kamil meteorite

    NASA Astrophysics Data System (ADS)

    Taricco, C.; Colombetti, P.; Bhandari, N.; Sinha, N.; Di Martino, M.; Vivaldo, G.

    2012-04-01

    Recently a small (45 m in diameter) and very young (< 5,000 years) impact crater was discovered in Egypt (Folco et al., 2010, 2011); it was generated by an iron meteorite named Gebel Kamil (Meteoritical Bulletin No. 98, Weisberg et al. 2010). During systematic searches, many specimens were found in the area surrounding the crater. We present the gamma-activity measurement of a 672 g fragment using a highly selective Ge-NaI spectrometer operating at Monte dei Cappuccini Laboratory (IFSI, INAF) in Torino, Italy. This apparatus allows to reveal the radioisotope activity generated by cosmic rays in the meteoroids as they travel through the interplanetary space before falling on the Earth. From the 26Al activity measurement and its depth production profiles, we infer (i) that the radius of the meteoroid should be about 1 m, constraining to 30-40 ton the range of pre-atmospheric mass previously proposed and (ii) that the fragment should have been located deeply inside the meteoroid, at a depth > 0.7 m. The 44Ti activity is under the detection threshold of the apparatus; using the depth production profiles of this radioisotope and its half-life T1/2 = 59.2 y, we deduce an upper limit to the date of fall.

  1. Actinium radioisotope products of enhanced purity

    DOEpatents

    Meikrantz, David Herbert; Todd, Terry Allen; Tranter, Troy Joseph; Horwitz, E. Philip

    2010-06-15

    A product includes actinium-225 (.sup.225Ac) and less than about 1 microgram (.mu.g) of iron (Fe) per millicurie (mCi) of actinium-225. The product may have a radioisotopic purity of greater than about 99.99 atomic percent (at %) actinium-225 and daughter isotopes of actinium-225, and may be formed by a method that includes providing a radioisotope mixture solution comprising at least one of uranium-233 (.sup.233U) and thorium-229 (.sup.229Th), extracting the at least one of uranium-233 and thorium-229 into an organic phase, substantially continuously contacting the organic phase with an aqueous phase, substantially continuously extracting actinium-225 into the aqueous phase, and purifying the actinium-225 from the aqueous phase. In some embodiments, the product may include less than about 1 nanogram (ng) of iron per millicurie (mCi) of actinium-225, and may include less than about 1 microgram (.mu.g) each of magnesium (Mg), Chromium (Cr), and manganese (Mn) per millicurie (mCi) of actinium-225.

  2. Central Venous Catheter Intravascular Malpositioning: Causes, Prevention, Diagnosis, and Correction

    PubMed Central

    Roldan, Carlos J.; Paniagua, Linda

    2015-01-01

    Despite the level of skill of the operator and the use of ultrasound guidance, central venous catheter (CVC) placement can result in CVC malpositioning, an unintended placement of the catheter tip in an inadequate vessel. CVC malpositioning is not a complication of central line insertion; however, undiagnosed CVC malpositioning can be associated with significant morbidity and mortality. The objectives of this review were to describe factors associated with intravascular malpositioning of CVCs inserted via the neck and chest and to offer ways of preventing, identifying, and correcting such malpositioning. A literature search of PubMed, Cochrane Library, and MD Consult was performed in June 2014. By searching for “Central line malposition” and then for “Central venous catheters intravascular malposition,” we found 178 articles written in English. Of those, we found that 39 were relevant to our objectives and included them in our review. According to those articles, intravascular CVC malpositioning is associated with the presence of congenital and acquired anatomical variants, catheter insertion in left thoracic venous system, inappropriate bevel orientation upon needle insertion, and patient’s body habitus variants. Although plain chest radiography is the standard imaging modality for confirming catheter tip location, signs and symptoms of CVC malpositioning even in presence of normal or inconclusive conventional radiography findings should prompt the use of additional diagnostic methods to confirm or rule out CVC malpositioning. With very few exceptions, the recommendation in cases of intravascular CVC malpositioning is to remove and relocate the catheter. Knowing the mechanisms of CVC malpositioning and how to prevent, identify, and correct CVC malpositioning could decrease harm to patients with this condition. PMID:26587087

  3. Transponder system for non-invasive measurement of intravascular pressure.

    PubMed

    Schnakenberg, U; Krüger, C; Pfeffer, J G; Mokwa, W; von Bögel, G; Günther, R; Schmitz-Rode, Th

    2002-01-01

    Monitoring of blood pressure and pulse rate offers diagnostical and therapeutical opportunities in hypertension disease and arrhythmia, respectively. This paper presents an intravascular pressure monitoring system consisting of an implantable silicone capsule, which can be placed in an arterial system via a catheter. The capsule contains a pressure sensor and signal conditioning circuits for wireless data and energy transfer using 6.78 MHz transponder technology.

  4. Disseminated intravascular coagulation and hepatocellular necrosis due to clove oil.

    PubMed

    Brown, S A; Biggerstaff, J; Savidge, G F

    1992-10-01

    We describe the case of a 2-year-old child who suffered from disseminated intravascular coagulation (DIC) and hepatocellular necrosis, following ingestion of clove oil. The patient was treated with heparin and fresh frozen plasma, and, following specific haemostasis assays, with appropriate coagulation factor and inhibitor concentrates. The case demonstrates how this approach can be successfully used in the management of DIC with coexisting liver failure. PMID:1450336

  5. Silent intravascular lymphoma initially manifesting as a unilateral adrenal incidentaloma.

    PubMed

    Takahashi, Yoshiko; Iida, Keiji; Hino, Yasuhisa; Ohara, Takeshi; Kurahashi, Toshifumi; Tashiro, Takashi; Chihara, Kazuo

    2012-01-01

    Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of malignant lymphoma. Although the involvement of adrenal glands in IVLBCL is often observed, primary adrenal IVLBCL is rare. Most reported cases of adrenal IVLBCL showed bilateral lesions resulting in rapidly progressive adrenal failure and poor prognosis. Here, we report a case of slowly progressive primary adrenal IVLBCL manifesting initially with unilateral adrenal incidentaloma. This case is a silent IVLBCL and shows that the enlargement of both adrenal glands can be followed.

  6. Optical device for intravascular low-power laser illumination

    NASA Astrophysics Data System (ADS)

    Grobelny, Andrzej; Palasz, Zbigniew; Beres-Pawlik, Elzbieta M.; Abramski, Krzysztof M.; Derkacz, Arkadiusz; Bialy, Dariusz; Protasiewicz, Marcin

    2003-04-01

    The treatment method presented in this paper is an adjunct to coronary angioplasty. It consists in irradiating a previously dilated artery with laser light which stimulates endothelium proliferation and reduces local inflammation. The influence of 808 nm laser light on the endothelium was studied in vitro. Because of the location of atherosclerotic plaques, illumination of the endothelium poses a problem. To overcome it, we have designed and built a laser set-up for homogeneous intravascular illumination in vivo.

  7. Central Venous Catheter Intravascular Malpositioning: Causes, Prevention, Diagnosis, and Correction.

    PubMed

    Roldan, Carlos J; Paniagua, Linda

    2015-09-01

    Despite the level of skill of the operator and the use of ultrasound guidance, central venous catheter (CVC) placement can result in CVC malpositioning, an unintended placement of the catheter tip in an inadequate vessel. CVC malpositioning is not a complication of central line insertion; however, undiagnosed CVC malpositioning can be associated with significant morbidity and mortality. The objectives of this review were to describe factors associated with intravascular malpositioning of CVCs inserted via the neck and chest and to offer ways of preventing, identifying, and correcting such malpositioning. A literature search of PubMed, Cochrane Library, and MD Consult was performed in June 2014. By searching for "Central line malposition" and then for "Central venous catheters intravascular malposition," we found 178 articles written in English. Of those, we found that 39 were relevant to our objectives and included them in our review. According to those articles, intravascular CVC malpositioning is associated with the presence of congenital and acquired anatomical variants, catheter insertion in left thoracic venous system, inappropriate bevel orientation upon needle insertion, and patient's body habitus variants. Although plain chest radiography is the standard imaging modality for confirming catheter tip location, signs and symptoms of CVC malpositioning even in presence of normal or inconclusive conventional radiography findings should prompt the use of additional diagnostic methods to confirm or rule out CVC malpositioning. With very few exceptions, the recommendation in cases of intravascular CVC malpositioning is to remove and relocate the catheter. Knowing the mechanisms of CVC malpositioning and how to prevent, identify, and correct CVC malpositioning could decrease harm to patients with this condition.

  8. Vascular wall stress during intravascular optical coherence tomography imaging

    NASA Astrophysics Data System (ADS)

    Sun, Cuiru; Yang, Victor

    2015-03-01

    Biomechanical properties of arterial wall is crucial for understanding the changes in the cardiovascular system. Catheters are used during intravascular optical coherence tomography (IVOCT) imaging. The presence of a catheter alters the flow field, pressure distribution and frictional resistance to flow in an artery. In this paper, we first study the transmural stress distribution of the catheterized vessel. COMSOL (COMSOL 4.4) was used to simulate the blood flow induced deformation in a catheterized vessel. Blood is modeled as an incompressible Newtonian fluid. Stress distribution from an three-layer vascular model with an eccentric catheter are simulated, which provides a general idea about the distribution of the displacement and the stress. Optical coherence elastography techniques were then applied to porcine carotid artery samples to look at the deformation status of the vascular wall during saline or water injection. Preliminary simulation results show nonuniform stress distribution in the circumferential direction of the eccentrically catheterized vascular model. Three strain rate methods were tested for intravascular OCE application. The tissue Doppler method has the potential to be further developed to image the vascular wall biomechnical properties in vivo. Although results in this study are not validated quantitatively, the experiments and methods may be valuable for intravascular OCE studies, which may provide important information for cardiovascular disease prevention, diagnosis and treatment.

  9. Integrated intravascular optical coherence tomography (OCT) - ultrasound (US) imaging system

    NASA Astrophysics Data System (ADS)

    Yin, Jiechen; Yang, Hao-Chung; Li, Xiang; Zhou, Qifa; Hu, Changhong; Zhang, Jun; Shung, K. Kirk; Chen, Zhongping

    2010-02-01

    Optical coherence tomography (OCT) and intravascular ultrasound (IVUS) are considered two complementary imaging techniques in the detection and diagnosis of atherosclerosis. OCT permits visualization of micron-scale features of atherosclerosis plaque, and IVUS offers full imaging depth of vessel wall. Under the guidance of IVUS, minimal amount of flushing agent will be needed to obtain OCT imaging of the interested area. We report on a dual-modality optical coherence tomography (OCT) - ultrasound (US) system for intravascular imaging. To the best of our knowledge, we have developed the first integrated OCT-US probe that combines OCT optical components with an ultrasound transducer. The OCT optical components mainly consist of a single mode fiber, a gradient index (GRIN) lens for light beam focusing, and a right-angled prism for reflecting light into biological tissue. A 40MHz PZT-5H side-viewing ultrasound transducer was fabricated to obtain the ultrasound image. These components were integrated into a single probe, enabling both OCT and ultrasound imaging at the same time. In vitro OCT and ultrasound images of a rabbit aorta were obtained using this dual-modality imaging system. This study demonstrates the feasibility of an OCT-US system for intravascular imaging which is expected to have a prominent impact on early detection and characterization of atherosclerosis.

  10. [Current status of intravascular ultrasound in interventional cardiology].

    PubMed

    Kovárník, Tomáš

    2014-12-01

    Although intravascular ultrasound has been used for decades, its common application in catheterization centres during coronary interventions is very rare and merely reaches few percents. The reason is the lack of randomized trials of its use and often few experiences in evaluation of ultrasound findings. Data based on meta-analysis of observational studies clearly demonstrated the positive effect on the most important parameters for the treatment of patients with ischemic heart disease, such as mortality and incidence of myocardial infarction after coronary interventions. Therefore, according to the latest guidelines for myocardial revascularization of the European Society of Cardiology is level of recommendation in category IIa for the use of intravascular ultrasound. IVUS continues to be an important part of new investigation methods which try to better describe coronary atherosclerosis. Particularly, it is the method NIRS (near-infrared spectroscopy) and other new methods of evaluating the composition and mechanical properties of plaque. These facts suggest that IVUS maintains its contribution in time of optical coherence tomography (OCT) and the emphasis put on the functional assessment of coronary stenoses.Key words: coronary atherosclerosis - intravascular ultrasound - percutaneous coronary intervention. PMID:25692833

  11. Renal denervation by intravascular ultrasound: Preliminary in vivo study

    NASA Astrophysics Data System (ADS)

    Sinelnikov, Yegor; McClain, Steve; Zou, Yong; Smith, David; Warnking, Reinhard

    2012-10-01

    Ultrasound denervation has recently become a subject of intense research in connection with the treatment of complex medical conditions including neurological conditions, development of pain management, reproduction of skin sensation, neuropathic pain and spasticity. The objective of this study is to investigate the use of intravascular ultrasound to produce nerve damage in renal sympathetic nerves without significant injury to the renal artery. This technique may potentially be used to treat various medical conditions, such as hypertension. The study was approved by the Institutional Animal Care and Use Committee. Ultrasound was applied to renal nerves of the swine model for histopathological evaluation. Therapeutic ultrasound energy was delivered circumferentially by an intravascular catheter maneuvered into the renal arteries. Fluoroscopic imaging was conducted pre-and post-ultrasound treatment. Animals were recovered and euthanized up to 30 hours post procedure, followed by necropsy and tissue sample collection. Histopathological examination showed evidence of extensive damage to renal nerves, characterized by nuclear pyknosis, hyalinization of stroma and multifocal hemorrhages, with little or no damage to renal arteries. This study demonstrates the feasibility of intravascular ultrasound as a minimally invasive renal denervation technique. Further studies are necessary to evaluate the long-term safety and efficacy of this technique and its related clinical significance.

  12. Assessment of radioisotope heaters for remote terrestrial applications

    SciTech Connect

    Uherka, K.L.

    1987-05-01

    This paper examines the feasibility of using radioisotope byproducts for special heating applications at remote sites in Alaska and other cold regions. The investigation included assessment of candidate radioisotope materials for heater applications, identification of the most promising cold region applications, evaluation of key technical issues and implementation constraints, and development of conceptual heater designs for candidate applications. Strontium-90 (Sr-90) was selected as the most viable fuel for radioisotopic heaters used in terrestrial applications. Opportunities for the application of radioisotopic heaters were determined through site visits to representative Alaska installations. Candidate heater applications included water storage tanks, sludge digesters, sewage lagoons, water piping systems, well-head pumping stations, emergency shelters, and fuel storage tank deicers. Radioisotopic heaters for water storage tank freeze-up protection and for enhancement of biological waste treatment processes at remote sites were selected as the most promising applications.

  13. Gamma radiation characteristics of plutonium dioxide fuel

    NASA Technical Reports Server (NTRS)

    Gingo, P. J.

    1969-01-01

    Investigation of plutonium dioxide as an isotopic fuel for Radioisotope Thermoelectric Generators yielded the isotopic composition of production-grade plutonium dioxide fuel, sources of gamma radiation produced by plutonium isotopes, and the gamma flux at the surface.

  14. Disseminated intravascular large-cell lymphoma with initial presentation mimicking Guillain-Barré syndrome.

    PubMed

    Jiang, Qin Li; Pytel, Peter; Rowin, Julie

    2010-07-01

    We report a patient with intravascular large B-cell lymphoma who initially presented with acute ascending weakness and sensory changes. Electrodiagnostic testing and cerebral spinal fluid (CSF) studies were initially suggestive of a demyelinating polyneuropathy. Further clinical evaluation and testing were consistent with mononeuropathy multiplex. Autopsy revealed disseminated intravascular large-cell lymphoma. Intravascular large-cell lymphoma should be considered in the differential diagnosis of a rapidly evolving neuropathy associated with other organ involvement.

  15. U.S. Space Radioisotope Power Systems and Applications: Past, Present and Future

    NASA Technical Reports Server (NTRS)

    Cataldo, Robert L.; Bennett, Gary L.

    2011-01-01

    Radioisotope power systems (RPS) have been essential to the U.S. exploration of outer space. RPS have two primary uses: electrical power and thermal power. To provide electrical power, the RPS uses the heat produced by the natural decay of a radioisotope (e.g., plutonium-238 in U.S. RPS) to drive a converter (e.g., thermoelectric elements or Stirling linear alternator). As a thermal power source the heat is conducted to whatever component on the spacecraft needs to be kept warm; this heat can be produced by a radioisotope heater unit (RHU) or by using the excess heat of a radioisotope thermoelectric generator (RTG). As of 2010, the U.S. has launched 41 RTGs on 26 space systems. These space systems have ranged from navigational satellites to challenging outer planet missions such as Pioneer 10/11, Voyager 1/2, Galileo, Ulysses, Cassini and the New Horizons mission to Pluto. In the fall of 2011, NASA plans to launch the Mars Science Laboratory (MSL) that will employ the new Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) as the principal power source. Hundreds of radioisotope heater units (RHUs) have been launched to provide warmth to Apollo 11, used to provide heating of critical components in a seismic experiment package, Pioneer 10/11, Voyager 1/2, Galileo, Cassini, Mars Pathfinder, MER rovers, etc. to provide temperature control to critical spacecraft electronics and other mechanical devices such as propulsion system propellant valves. A radioisotope (electrical) power source or system (RPS) consists of three basic elements: (1) the radioisotope heat source that provides the thermal power, (2) the converter that transforms the thermal power into electrical power and (3) the heat rejection radiator. Figure 1 illustrates the basic features of an RPS. The idea of a radioisotope power source follows closely after the early investigations of radioactivity by researchers such as Henri Becquerel (1852-1908), Marie Curie (1867-1935), Pierre Curie (1859

  16. Voyager electronic parts radiation program, volume 1

    NASA Technical Reports Server (NTRS)

    Stanley, A. G.; Martin, K. E.; Price, W. E.

    1977-01-01

    The Voyager spacecraft is subject to radiation from external natural space, from radioisotope thermoelectric generators and heater units, and from the internal environment where penetrating electrons generate surface ionization effects in semiconductor devices. Methods for radiation hardening and tests for radiation sensitivity are described. Results of characterization testing and sample screening of over 200 semiconductor devices in a radiation environment are summarized.

  17. Design, construction, and validation of a rotary multifunctional intravascular diagnostic catheter combining multispectral fluorescence lifetime imaging and intravascular ultrasound.

    PubMed

    Bec, Julien; Xie, Hongtao; Yankelevich, Diego R; Zhou, Feifei; Sun, Yang; Ghata, Narugopal; Aldredge, Ralph; Marcu, Laura

    2012-10-01

    We report the development and validation of an intravascular rotary catheter for bimodal interrogation of arterial pathologies. This is based on a point-spectroscopy scanning time-resolved fluorescence spectroscopy technique enabling reconstruction of fluorescence lifetime images (FLIm) and providing information on arterial intima composition and intravascular ultrasound (IVUS) providing information on arterial wall morphology. The catheter design allows for independent rotation of the ultrasonic and optical channels within an 8 Fr outer diameter catheter sheath and integrates a low volume flushing channel for blood removal in the optical pathways. In the current configuration, the two channels consist of (a) a standard 3 Fr IVUS catheter with single element transducer (40 MHz) and (b) a side-viewing fiber optic (400 μm core). Experiments conducted in tissue phantoms showed the ability of the catheter to operate in an intraluminal setting and to generate coregistered FLIm and IVUS in one pull-back scan. Current results demonstrate the feasibility of the catheter for simultaneous bimodal interrogation of arterial lumen and for generation of robust fluorescence lifetime data under IVUS guidance. These results facilitate further development of a FLIm-IVUS technique for intravascular diagnosis of atherosclerotic cardiovascular diseases including vulnerable plaques.

  18. Design, construction, and validation of a rotary multifunctional intravascular diagnostic catheter combining multispectral fluorescence lifetime imaging and intravascular ultrasound

    NASA Astrophysics Data System (ADS)

    Bec, Julien; Xie, Hongtao; Yankelevich, Diego R.; Zhou, Feifei; Sun, Yang; Ghata, Narugopal; Aldredge, Ralph; Marcu, Laura

    2012-10-01

    We report the development and validation of an intravascular rotary catheter for bimodal interrogation of arterial pathologies. This is based on a point-spectroscopy scanning time-resolved fluorescence spectroscopy technique enabling reconstruction of fluorescence lifetime images (FLIm) and providing information on arterial intima composition and intravascular ultrasound (IVUS) providing information on arterial wall morphology. The catheter design allows for independent rotation of the ultrasonic and optical channels within an 8 Fr outer diameter catheter sheath and integrates a low volume flushing channel for blood removal in the optical pathways. In the current configuration, the two channels consist of (a) a standard 3 Fr IVUS catheter with single element transducer (40 MHz) and (b) a side-viewing fiber optic (400 μm core). Experiments conducted in tissue phantoms showed the ability of the catheter to operate in an intraluminal setting and to generate coregistered FLIm and IVUS in one pull-back scan. Current results demonstrate the feasibility of the catheter for simultaneous bimodal interrogation of arterial lumen and for generation of robust fluorescence lifetime data under IVUS guidance. These results facilitate further development of a FLIm-IVUS technique for intravascular diagnosis of atherosclerotic cardiovascular diseases including vulnerable plaques.

  19. Rhenium-188 Labeled Tungsten Disulfide Nanoflakes for Self-Sensitized, Near-Infrared Enhanced Radioisotope Therapy.

    PubMed

    Chao, Yu; Wang, Guanglin; Liang, Chao; Yi, Xuan; Zhong, Xiaoyan; Liu, Jingjing; Gao, Min; Yang, Kai; Cheng, Liang; Liu, Zhuang

    2016-08-01

    Radioisotope therapy (RIT), in which radioactive agents are administered or implanted into the body to irradiate tumors from the inside, is a clinically adopted cancer treatment method but still needs improvement to enhance its performances. Herein, it is found that polyethylene glycol (PEG) modified tungsten disulfide (WS2 ) nanoflakes can be easily labeled by (188) Re, a widely used radioisotope for RIT, upon simple mixing. Like other high-Z elements acting as radiosensitizers, tungsten in the obtained (188) Re-WS2 -PEG would be able to absorb ionization radiation generated from (188) Re, enabling ''self-sensitization'' to enhance the efficacy of RIT as demonstrated in carefully designed in vitro experiments of this study. In the meanwhile, the strong NIR absorbance of WS2 -PEG could be utilized for NIR light-induced photothermal therapy (PTT), which if applied on tumors would be able to greatly relieve their hypoxia state and help to overcome hypoxia-associated radioresistance of tumors. Therefore, with (188) Re-WS2 -PEG as a multifunctional agent, which shows efficient passive tumor homing after intravenous injection, in vivo self-sensitized, NIR-enhanced RIT cancer treatment is realized, achieving excellent tumor killing efficacy in a mouse tumor model. This work presents a new concept of applying nanotechnology in RIT, by delivering radioisotopes into tumors, self-sensitizing the irradiation-induced cell damage, and modulating the tumor hypoxia state to further enhance the therapeutic outcomes. PMID:27345460

  20. Specification for strontium-90 500-watt(e) radioisotopic thermoelectric generator. Final report

    SciTech Connect

    Hammel, T.; Himes, J.; Lieberman, A.; McGrew, J.; Owings, D.; Schumann, F.

    1983-04-01

    A conceptual design for a demonstration 500-watt(e) radioisotopic thermoelectric generator has been created for the Department of Energy. The design effort was divided into two tasks, viz., create a design specification for a capsule strength member that utilizes a standard Strontium-90 fluoride-filled WESF inner liner, and create a conceptual design for a 500-watt(e) RTG. Both tasks have been accomplished. The strength-member specification was designed to survive an external pressure of 24,500 psi and meet the requirements of special-form radioisotope heat sources. Therefore the capsule can, if desired, be licensed for domestic and international transport. The design for the RTG features a radioisotopic heat source, an array of nine capsules in a tungsten biological shield, four current-technology series-connected thermoelectric-conversion modules, low-conductivity thermal insulation, and a passive finned-housing radiator for waste-heat dissipation. The preliminary RTG specification formulated previous to contract award has been met or exceeded. The power source will generate the required power for the required service period at 28 volts dc with a conversion efficiency of 8%, provided the existing in-pool capsules at WESF meet the assumed thermal-inventory requirements.

  1. Penetration of an artificial arterial thromboembolism in a live animal using an intravascular therapeutic microrobot system.

    PubMed

    Jeong, Semi; Choi, Hyunchul; Go, Gwangjun; Lee, Cheong; Lim, Kyung Seob; Sim, Doo Sun; Jeong, Myung Ho; Ko, Seong Young; Park, Jong-Oh; Park, Sukho

    2016-04-01

    The biomedical applications of wireless robots are an active area of study. In addition to moving to a target lesion, wireless locomotive robots can deliver a therapeutic drug for a specific disease. Thus, they hold great potential as therapeutic devices in blood vessel diseases, such as thrombi and occlusions, and in other diseases, such as cancer and inflammation. During a percutaneous coronary intervention (PCI), surgeons wear a heavy shielding cloth. However, they cannot escape severe radiation exposure owing to unstable shielding. They may also suffer from joint pains because of the weight of the shielding cloth. In addition, the catheters in PCIs are controlled by the surgeon's hand. Thus, they lack steering ability. A new intravascular therapeutic system is needed to address these problems in conventional PCIs. We developed an intravascular therapeutic microrobot system (ITMS) using an electromagnetic actuation (EMA) system with bi-plane X-ray devices that can remotely control a robot in blood vessels. Using this proposed ITMS, we demonstrated the locomotion of the robot in abdominal and iliac arteries of a live pig by the master-slave method. After producing an arterial thromboembolism in a live pig in a partial iliac artery, the robot moved to the target lesion and penetrated by specific motions (twisting and hammering) of the robot using the proposed ITMS. The results reveal that the proposed ITMS can realize stable locomotion (alignment and propulsion) of a robot in abdominal and iliac arteries of a live pig. This can be considered the first preclinical trial of the treatment of an artificial arterial thromboembolism by penetration of a blood clot.

  2. Penetration of an artificial arterial thromboembolism in a live animal using an intravascular therapeutic microrobot system.

    PubMed

    Jeong, Semi; Choi, Hyunchul; Go, Gwangjun; Lee, Cheong; Lim, Kyung Seob; Sim, Doo Sun; Jeong, Myung Ho; Ko, Seong Young; Park, Jong-Oh; Park, Sukho

    2016-04-01

    The biomedical applications of wireless robots are an active area of study. In addition to moving to a target lesion, wireless locomotive robots can deliver a therapeutic drug for a specific disease. Thus, they hold great potential as therapeutic devices in blood vessel diseases, such as thrombi and occlusions, and in other diseases, such as cancer and inflammation. During a percutaneous coronary intervention (PCI), surgeons wear a heavy shielding cloth. However, they cannot escape severe radiation exposure owing to unstable shielding. They may also suffer from joint pains because of the weight of the shielding cloth. In addition, the catheters in PCIs are controlled by the surgeon's hand. Thus, they lack steering ability. A new intravascular therapeutic system is needed to address these problems in conventional PCIs. We developed an intravascular therapeutic microrobot system (ITMS) using an electromagnetic actuation (EMA) system with bi-plane X-ray devices that can remotely control a robot in blood vessels. Using this proposed ITMS, we demonstrated the locomotion of the robot in abdominal and iliac arteries of a live pig by the master-slave method. After producing an arterial thromboembolism in a live pig in a partial iliac artery, the robot moved to the target lesion and penetrated by specific motions (twisting and hammering) of the robot using the proposed ITMS. The results reveal that the proposed ITMS can realize stable locomotion (alignment and propulsion) of a robot in abdominal and iliac arteries of a live pig. This can be considered the first preclinical trial of the treatment of an artificial arterial thromboembolism by penetration of a blood clot. PMID:26857290

  3. Thermophotovoltaic Converter Design for Radioisotope Power Systems

    NASA Astrophysics Data System (ADS)

    Crowley, Christopher J.; Murray, Susan; Murray, Christopher; Elkouh, Nabil A.

    2004-02-01

    The development of lightweight, efficient power for emerging NASA missions and recent advances in thermophotovoltaic (TPV) conversion technology have renewed interest in combining radioisotope heat sources with photovoltaic energy conversion. Thermophotovoltaic power conversion uses advanced materials able to utilize a broader, spectrally tuned range of wavelengths for more efficient power conversion than solar cells. Spectral control, including selective emitters, TPV module, and filters, are key to high-efficiency operation. This paper outlines the mechanical, thermal, and optical designs for the converter, including the heat source, the selective emitter, filters, photovoltaic (PV) cells, and optical cavity components. Focus is on the emitter type and the band-gap of InGaAs PV cells in developing the design. Any component and converter data available at the time of publication will also be presented.

  4. Radioisotope Power Systems Program: A Program Overview

    NASA Technical Reports Server (NTRS)

    Hamley, John A.

    2016-01-01

    NASA's Radioisotope Power Systems (RPS) Program continues to plan, mature research in energy conversion, and partners with the Department of Energy (DOE) to make RPS ready and available to support the exploration of the solar system in environments where the use of conventional solar or chemical power generation is impractical or impossible to meet potential future mission needs. Recent programs responsibilities include providing investment recommendations to NASA stakeholders on emerging thermoelectric and Stirling energy conversion technologies and insight on NASA investments at DOE in readying a generator for the Mars 2020 mission. This presentation provides an overview of the RPS Program content and status and the approach used to maintain the readiness of RPS to support potential future NASA missions.

  5. Radioisotope Power System Facility shielding analysis

    SciTech Connect

    Lu, A.H.; Morford, R.J.

    1989-01-01

    A series of calculations for the Radioisotope Power System Facility have been performed. These analyses have determined the shielding required for storage, testing, and transport of /sup 238/Pu heat source modules using the Monte Carlo code MCNP3B. The source terms and the assumptions used have been verified by comparison of calculated dose rates with measured ones. This paper describes the methodology used for shielding designs and the utilization of available variance reduction techniques to improve the computational efficiency. The new version of MCNP (MCNP3B) with a repeated structure capability was used. It decreased the chance for computer model errors and greatly decreased the model setup time. 2 refs., 3 figs., 2 tabs.

  6. Induced radioisotopes in a linac treatment hall.

    PubMed

    Vega-Carrillo, Héctor René; de Leon-Martinez, Héctor Asael; Rivera-Perez, Esteban; Luis Benites-Rengifo, Jorge; Gallego, Eduardo; Lorente, Alfredo

    2015-08-01

    When linacs operate above 8MV an undesirable neutron field is produced whose spectrum has three main components: the direct spectrum due to those neutrons leaking out from the linac head, the scattered spectrum due to neutrons produced in the head that collides with the nuclei in the head losing energy and the third spectrum due to room-return effect. The third category of spectrum has mainly epithermal and thermal neutrons being constant at any location in the treatment hall. These neutrons induce activation in the linac components, the concrete walls and in the patient body. Here the induced radioisotopes have been identified in concrete samples located in the hall and in one of the wedges. The identification has been carried out using a gamma-ray spectrometer.

  7. Thermophotovoltaic Converter Design for Radioisotope Power Systems

    SciTech Connect

    Crowley, Christopher J.; Elkouh, Nabil A.; Murray, Susan; Murray, Christopher

    2004-02-04

    The development of lightweight, efficient power for emerging NASA missions and recent advances in thermophotovoltaic (TPV) conversion technology have renewed interest in combining radioisotope heat sources with photovoltaic energy conversion. Thermophotovoltaic power conversion uses advanced materials able to utilize a broader, spectrally tuned range of wavelengths for more efficient power conversion than solar cells. Spectral control, including selective emitters, TPV module, and filters, are key to high-efficiency operation. This paper outlines the mechanical, thermal, and optical designs for the converter, including the heat source, the selective emitter, filters, photovoltaic (PV) cells, and optical cavity components. Focus is on the emitter type and the band-gap of InGaAs PV cells in developing the design. Any component and converter data available at the time of publication will also be presented.

  8. Energy Recovery Linacs for Commercial Radioisotope Production

    SciTech Connect

    Sy, Amy; Krafft, Geoffrey A.; Johnson, Rolland; Roberts, Tom; Boulware, Chase; Hollister, Jerry

    2015-09-01

    Photonuclear reactions with bremsstrahlung photon beams from electron linacs can generate radioisotopes of critical interest. An SRF Energy Recovery Linac (ERL) provides a path to a more diverse and reliable domestic supply of short-lived, high-value, high-demand isotopes in a more compact footprint and at a lower cost than those produced by conventional reactor or ion accelerator methods. Use of an ERL enables increased energy efficiency of the complex through energy recovery of the waste electron beam, high electron currents for high production yields, and reduced neutron production and shielding activation at beam dump components. Simulation studies using G4Beamline/GEANT4 and MCNP6 through MuSim, as well as other simulation codes, will design an ERL-based isotope production facility utilizing bremsstrahlung photon beams from an electron linac. Balancing the isotope production parameters versus energy recovery requirements will inform a choice of isotope production target for future experiments.

  9. Production of medical radioisotopes with linear accelerators.

    PubMed

    Starovoitova, Valeriia N; Tchelidze, Lali; Wells, Douglas P

    2014-02-01

    In this study, we discuss producing radioisotopes using linear electron accelerators and address production and separation issues of photoneutron (γ,n) and photoproton (γ,p) reactions. While (γ,n) reactions typically result in greater yields, separating product nuclides from the target is challenging since the chemical properties of both are the same. Yields of (γ,p) reactions are typically lower than (γ,n) ones, however they have the advantage that target and product nuclides belong to different chemical species so their separation is often not such an intricate problem. In this paper we consider two examples, (100)Mo(γ,n)(99)Mo and (68)Zn(γ,p)(67)Cu, of photonuclear reactions. Monte-Carlo simulations of the yields are benchmarked with experimental data obtained at the Idaho Accelerator Center using a 44MeV linear electron accelerator. We propose using a kinematic recoil method for photoneutron production. This technique requires (100)Mo target material to be in the form of nanoparticles coated with a catcher material. During irradiation, (99)Mo atoms recoil and get trapped in the coating layer. After irradiation, the coating is dissolved and (99)Mo is collected. At the same time, (100)Mo nanoparticles can be reused. For the photoproduction method, (67)Cu can be separated from the target nuclides, (68)Zn, using standard exchange chromatography methods. Monte-Carlo simulations were performed and the (99)Mo activity was predicted to be about 7MBq/(g(⁎)kW(⁎)h) while (67)Cu activity was predicted to be about 1MBq/(g(⁎)kW(⁎)h). Experimental data confirm the predicted activity for both cases which proves that photonuclear reactions can be used to produce radioisotopes. Lists of medical isotopes which might be obtained using photonuclear reactions have been compiled and are included as well. PMID:24374071

  10. Production of medical radioisotopes with linear accelerators.

    PubMed

    Starovoitova, Valeriia N; Tchelidze, Lali; Wells, Douglas P

    2014-02-01

    In this study, we discuss producing radioisotopes using linear electron accelerators and address production and separation issues of photoneutron (γ,n) and photoproton (γ,p) reactions. While (γ,n) reactions typically result in greater yields, separating product nuclides from the target is challenging since the chemical properties of both are the same. Yields of (γ,p) reactions are typically lower than (γ,n) ones, however they have the advantage that target and product nuclides belong to different chemical species so their separation is often not such an intricate problem. In this paper we consider two examples, (100)Mo(γ,n)(99)Mo and (68)Zn(γ,p)(67)Cu, of photonuclear reactions. Monte-Carlo simulations of the yields are benchmarked with experimental data obtained at the Idaho Accelerator Center using a 44MeV linear electron accelerator. We propose using a kinematic recoil method for photoneutron production. This technique requires (100)Mo target material to be in the form of nanoparticles coated with a catcher material. During irradiation, (99)Mo atoms recoil and get trapped in the coating layer. After irradiation, the coating is dissolved and (99)Mo is collected. At the same time, (100)Mo nanoparticles can be reused. For the photoproduction method, (67)Cu can be separated from the target nuclides, (68)Zn, using standard exchange chromatography methods. Monte-Carlo simulations were performed and the (99)Mo activity was predicted to be about 7MBq/(g(⁎)kW(⁎)h) while (67)Cu activity was predicted to be about 1MBq/(g(⁎)kW(⁎)h). Experimental data confirm the predicted activity for both cases which proves that photonuclear reactions can be used to produce radioisotopes. Lists of medical isotopes which might be obtained using photonuclear reactions have been compiled and are included as well.

  11. Status of the NASA Stirling Radioisotope Project

    NASA Technical Reports Server (NTRS)

    Schreiber, Jeffrey G.

    2007-01-01

    Free-piston Stirling power conversion has been considered a candidate for radioisotope power systems for space for more than a decade. Prior to the free-piston Stirling architecture, systems were designed with kinematic Stirling engines that used linkages and rotary alternators to convert heat to electricity. These systems were able to achieve long life by lightly loading the linkages; however, the live was nonetheless limited. When the free-piston configuration was initially proposed, it was thought to be attractive due to the relatively high conversion efficiency, acceptable mass, and the potential for long life and high reliability based on wear-free operation. These features have consistently been recognized by teams that have studied technology options for radioisotope space power systems. Since free-piston Stirling power conversion was first considered for space power applications, there have been major advances in three general areas of development: hardware that has demonstrated long-life and reliability, the success achieved by Stirling cryocoolers in space, and the overall developmental maturity of the technology for both space and terrestrial applications. Based on these advances, free-piston Stirling convertors are currently being developed for space power, and for a number of terrestrial applications. They commonly operate with the power, efficiency, life, and reliability as intended, and much of the development now centers on system integration. This paper will summarize the accomplishments of free-piston Stirling power conversion technology over the past decade, review the status of development with regard to space power, and discuss the challenges that remain.

  12. Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    NASA Technical Reports Server (NTRS)

    Anderson, William G.; Tarau, Calin

    2008-01-01

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling convertor provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) was designed to allow multiple stops and restarts of the Stirling engine. A VCHP turns on with a delta T of 30 C, which is high enough to not risk standard ASRG operation but low enough to save most heater head life. This VCHP has a low mass, and low thermal losses for normal operation. In addition to the design, a proof-of-concept NaK VCHP was fabricated and tested. While NaK is normally not used in heat pipes, it has an advantage in that it is liquid at the reservoir operating temperature, while Na or K alone would freeze. The VCHP had two condensers, one simulating the heater head, and the other simulating the radiator. The experiments successfully demonstrated operation with the simulated heater head condenser off and on, while allowing the reservoir temperature to vary over 40 to 120 C, the maximum range expected. In agreement with previous NaK heat pipe tests, the evaporator delta T was roughly 70 C, due to distillation of the NaK in the evaporator.

  13. Analytical thermal model validation for Cassini radioisotope thermoelectric generator

    SciTech Connect

    Lin, E.I.

    1997-12-31

    The Saturn-bound Cassini spacecraft is designed to rely, without precedent, on the waste heat from its three radioisotope thermoelectric generators (RTGs) to warm the propulsion module subsystem, and the RTG end dome temperature is a key determining factor of the amount of waste heat delivered. A previously validated SINDA thermal model of the RTG was the sole guide to understanding its complex thermal behavior, but displayed large discrepancies against some initial thermal development test data. A careful revalidation effort led to significant modifications and adjustments of the model, which result in a doubling of the radiative heat transfer from the heat source support assemblies to the end domes and bring up the end dome and flange temperature predictions to within 2 C of the pertinent test data. The increased inboard end dome temperature has a considerable impact on thermal control of the spacecraft central body. The validation process offers an example of physically-driven analytical model calibration with test data from not only an electrical simulator but also a nuclear-fueled flight unit, and has established the end dome temperatures of a flight RTG where no in-flight or ground-test data existed before.

  14. Report on audit of funding for advanced radioisotope power systems

    SciTech Connect

    1997-10-17

    The U.S. Department of Energy`s (Department) Advanced Radioisotope Power Systems Program maintains the sole national capability and facilities to produce radioisotope power systems for the National Aeronautics and Space Administration (NASA), the Department of Defense, and other Federal agencies. Projects are conducted with these agencies in accordance with written agreements and are dependent on cost sharing by the user agencies. For the past seven years the program emphasis has been on providing power systems for NASA`s Cassini mission to Saturn, which was launched earlier this month. We initiated this audit to determine whether the Department received proper reimbursement from NASA for the radioisotope power systems produced.

  15. Radioisotope Reduction Using Solar Power for Outer Planetary Missions

    NASA Technical Reports Server (NTRS)

    Fincannon, James

    2008-01-01

    Radioisotope power systems have historically been (and still are) the power system of choice from a mass and size perspective for outer planetary missions. High demand for and limited availability of radioisotope fuel has made it necessary to investigate alternatives to this option. Low mass, high efficiency solar power systems have the potential for use at low outer planetary temperatures and illumination levels. This paper documents the impacts of using solar power systems instead of radioisotope power for all or part of the power needs of outer planetary spacecraft and illustrates the potential fuel savings of such an approach.

  16. Radioisotope tracer studies in the NASA Skylab ethothermic brazing experiment M-552

    NASA Technical Reports Server (NTRS)

    Braski, D. N.; Adair, H. L.; Kobisk, E. H.

    1974-01-01

    The first use of radioisotope tracer for mapping flow patterns during brazing of metal components in a space environment (near-zero gravity) proved successful. A nickel ferrule was brazed to a nickel tube with Lithobraze BT (71.8% Ag, 28% Cu, 0.2% Li) which contained a trace amount of radioactive Ag-110. Mapping of the flow of the braze alloy in the annulus formed between the tube and the concentric ferrule was determined by counting the radiation intensity as a function of position in the braze joint. Significant information concerning the thermal history of the braze was determined.

  17. Environmental assessment of decommissioning radioisotope thermoelectric generators (RTG) in northwest Russia

    SciTech Connect

    Hosseini, A.; Standring, W.J.F.; Brown, J.E.; Dowdall, M.; Amundsen, I.B.

    2007-07-01

    This article presents some results from assessment work conducted as part of a joint Norwegian-Russian project to decommission radioisotope thermoelectric generators (RTG) in Northwest Russia. Potential worst case accident scenarios, based on the decommissioning procedures for RTGs, were assessed to study possible radiation effects to the environment. Close contact with exposed RTG sources will result in detrimental health effects. However, doses to marine biota from ingestion of radioactivity under the worst-case marine scenario studied were lower than threshold limits given in IAEA literature. (authors)

  18. Environmental, health and safety assessment of decommissioning radioisotope thermoelectric generators (RTGs) in northwest Russia.

    PubMed

    Standring, W J F; Dowdall, M; Sneve, M; Selnaes, Ø G; Amundsen, I

    2007-09-01

    This paper presents findings from public health and environmental assessment work that has been conducted as part of a joint Norwegian-Russian project to decommission radioisotope thermoelectric generators (RTG) in northwest Russia. RTGs utilise heat energy from radioactive isotopes, in this case 90Sr and its daughter nuclide 90Y, to generate electricity as a power source. Different accident scenarios based on the decommissioning process for RTGs are assessed in terms of possible radiation effects to humans and the environment. Doses to humans and biota under the worst-case scenario were lower than threshold limits given in ICRP and IAEA literature.

  19. Bothrops jararaca envenomation: Pathogenesis of hemostatic disturbances and intravascular hemolysis

    PubMed Central

    Senise, Luana V; Yamashita, Karine M

    2015-01-01

    To attain fully functional biological activity, vitamin-K dependent coagulation factors (VKDCF) are γ-carboxylated prior to secretion from liver. Warfarin impairs the γ-carboxylation, and consequently their physiological function. Bothrops jararaca snake venom (BjV) contains several activators of blood coagulation, especially procoagulant enzymes (prothrombin and factor X activators) and thrombin-like enzymes. In order to clarify the relative contribution of prothrombin and factor X activators to the hemostatic disturbances occurring during experimental B. jararaca envenomation, warfarin was used to deplete VKDCF, prior to BjV administration. Male Wistar rats were pretreated with saline (Sal) or warfarin (War) and inoculated subsequently with BjV or saline, thus forming four groups: Sal + Sal (negative control), Sal + BjV (positive control), War + Sal (warfarinization control), and War + BjV. Three hours after inoculation, prothrombin and factor X levels fell 40% and 50%, respectively; levels of both factors decreased more than 97% in the War + Sal and War + BjV groups. Platelet counts dropped 93% and 76% in Sal + BjV and War + BjV, respectively, and plasma fibrinogen levels decreased 86% exclusively in Sal + BjV. After 6 and 24 h, platelet counts and fibrinogen levels increased progressively. A dramatic augmentation in plasma hemoglobin levels and the presence of schizocytes and microcytes in the Sal + BjV group indicated the development of intravascular hemolysis, which was prevented by warfarin pretreatment. Our findings show that intravascular thrombin generation has the foremost role in the pathogenesis of coagulopathy and intravascular hemolysis, but not in the development of thrombocytopenia, in B. jararaca envenomation in rats; in addition, fibrinogenases (metalloproteinases) may contribute to coagulopathy more than thrombin-like enzymes. PMID:26080462

  20. 21 CFR 880.5970 - Percutaneous, implanted, long-term intravascular catheter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...: “Guidance on Premarket Notification Submission for Short-Term and Long-Term Intravascular Catheters.” ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Percutaneous, implanted, long-term intravascular... and Personal Use Therapeutic Devices § 880.5970 Percutaneous, implanted, long-term...

  1. 21 CFR 880.5970 - Percutaneous, implanted, long-term intravascular catheter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...: “Guidance on Premarket Notification Submission for Short-Term and Long-Term Intravascular Catheters.” ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Percutaneous, implanted, long-term intravascular... and Personal Use Therapeutic Devices § 880.5970 Percutaneous, implanted, long-term...

  2. 21 CFR 880.5970 - Percutaneous, implanted, long-term intravascular catheter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...: “Guidance on Premarket Notification Submission for Short-Term and Long-Term Intravascular Catheters.” ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Percutaneous, implanted, long-term intravascular... and Personal Use Therapeutic Devices § 880.5970 Percutaneous, implanted, long-term...

  3. [Incidence of biological intravascular coagulation in legal induced abortions].

    PubMed

    Boudaoud, S; Eurin, B; Drouet, L; Alhomme, P; Dreyfus, R; Serfaty, D

    1986-01-01

    A prospective study was designed to evaluate coagulation abnormalities induced by early abortion (before ten weeks of pregnancy). Fifty-two women underwent suction abortion, under diazepam-fentanyl anaesthesia with spontaneous ventilation; they were screened for coagulation parameters before and after surgery. Eight tests were carried out: prothrombin time, activated partial thromboplastin time (APTT), thrombin time platelet count, fibrinogen levels, fibrin split products, fibrin soluble complexes and euglobulin lysis time. Results were consistent with activation. Consequences were limited and one general test (APTT) was not significantly modified. Suction abortion, even performed in early pregnancy, exposed to biological disseminated intravascular coagulation with a general risk of venous thrombosis.

  4. Disseminated Intravascular Coagulation after Surgery for Facial Injury

    PubMed Central

    Tachibana, Hirohiko; Ishikawa, Shigeo; Yusa, Kazuyuki; Kitabatake, Kenichirou; Iino, Mitsuyoshi

    2016-01-01

    A case of disseminated intravascular coagulation (DIC) presenting after surgery for facial trauma associated with multiple facial bone fractures is described. With regard to the oral and maxillofacial region, DIC has been described in the literature following head trauma, infection, and metastatic disease. Until now, only 5 reports have described DIC after surgery for facial injury. DIC secondary to facial injury is thus rare. The patient in this case was young and had no medical history. Preoperative hemorrhage or postoperative septicemia may thus induce DIC. PMID:27313913

  5. Application of tissue characterization in intravascular ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Mullen, William L.; Fitzgerald, Peter J.; Yock, Paul G.

    1994-05-01

    Current intravascular ultrasound imaging technology is able to determine the extent and distribution of pathologic processes within the vessel wall, but is not highly sensitive in discriminating between certain types of tissue. `Tissue characterization' refers to a set of computer-based techniques that utilize features of the ultrasound signal beyond basic amplitude to help define the composition of the tissue of interest. This technique involves quantitative analysis of the ultrasound signals reflected from tissue before these signals pass through the processing steps in the ultrasound instrument.

  6. Venous gas embolism - Time course of residual pulmonary intravascular bubbles

    NASA Technical Reports Server (NTRS)

    Butler, B. D.; Luehr, S.; Katz, J.

    1989-01-01

    A study was carried out to determine the time course of residual pulmonary intravascular bubbles after embolization with known amounts of venous air, using an N2O challenge technique. Attention was also given to the length of time that the venous gas emboli remained as discrete bubbles in the lungs with 100 percent oxygen ventilation. The data indicate that venous gas emboli can remain in the pulmonary vasculature as discrete bubbles for periods lasting up to 43 + or - 10.8 min in dogs ventilated with oxygen and nitrogen. With 100 percent oxygen ventilation, these values are reduced significantly to 19 + or - 2.5 min.

  7. Intravascular filarial parasites elaborate cyclooxygenase-derived eicosanoids

    PubMed Central

    1990-01-01

    The nematode parasites that cause human lymphatic filariasis survive for long periods in their vascular habitats despite continual exposure to host cells. Since prostanoids formed from arachidonic acid can modulate interactions among platelets, leukocytes, and endothelial cells, we examined whether intravascular nematode parasites can elaborate prostanoids. Microfilariae of Brugia malayi utilize exogenous and endogenous arachidonic acid to generate and release two predominant prostanoids, prostacyclin and prostaglandin E2. Filarial metabolism of host fatty acids to form these vasodilatory, antiaggregatory, and immunomodulatory eicosanoids provides a means by which these helminthic parasites may influence host immune and other cellular responses. PMID:2117642

  8. Removal of Chronic Intravascular Blood Clots using Liquid Plasma

    NASA Astrophysics Data System (ADS)

    Jung, Jae-Chul; Choi, Myeong; Koo, Il; Yu, Zengqi; Collins, George

    2011-10-01

    An electrical embolectomy device for removing chronic intravascular blood clots using liquid plasma under saline environment was demonstrated. We employed a proxy experimental blood clot model of deep vein thrombosis (DVT) and actual equine blood clot. Thermal damage to contiguous tissue and the collagen denaturing via the plasma irradiation were investigated by histological analysis using birefringence of the tissue and verified by FT-IR spectroscopic study, respectively, which showed the high removal rate up to 2 mm per minute at room temperature and small thermal damage less than 200 μm.

  9. Determining Molar Combining Ratios Using Radioisotopes--A Student Experiment

    ERIC Educational Resources Information Center

    Sears, Jerry A.

    1976-01-01

    Outlines an experimental procedure in which an iodine radioisotope is used to determine molar combining ratios of lead and silver with the iodine. Tables and graphs show the definitive results that should be attainable. (CP)

  10. A power conditioning system for radioisotope thermoelectric generator energy sources

    NASA Technical Reports Server (NTRS)

    Gillis, J. A., Jr.

    1974-01-01

    The use of radioisotope thermoelectric generators (RTG) as the primary source of energy in unmanned spacecraft is discussed. RTG output control, power conditioning system requirements, the electrical design, and circuit performance are also discussed.

  11. A historical perspective on radioisotopic tracers in metabolism and biochemistry.

    PubMed

    Lappin, Graham

    2015-01-01

    Radioisotopes are used routinely in the modern laboratory to trace and quantify a myriad of biochemical processes. The technique has a captivating history peppered with groundbreaking science and with more than its share of Nobel Prizes. The discovery of radioactivity at the end of the 19th century paved the way to understanding atomic structure and quickly led to the use of radioisotopes to trace the fate of molecules as they flowed through complex organic life. The 1940s saw the first radiotracer studies using homemade instrumentation and analytical techniques such as paper chromatography. This article follows the history of radioisotopic tracers from meager beginnings, through to the most recent applications. The author hopes that those researchers involved in radioisotopic tracer studies today will pause to remember the origins of the technique and those who pioneered this fascinating science.

  12. Thermal Model Predictions of Advanced Stirling Radioisotope Generator Performance

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen J.; Fabanich, William Anthony; Schmitz, Paul C.

    2014-01-01

    This presentation describes the capabilities of three-dimensional thermal power model of advanced stirling radioisotope generator (ASRG). The performance of the ASRG is presented for different scenario, such as Venus flyby with or without the auxiliary cooling system.

  13. Effectiveness Evaluation of Skin Covers against Intravascular Brachytherapy Sources Using VARSKIN3 Code

    PubMed Central

    Baghani, H R; Nazempour, A R; Aghamiri, S M R; Hosseini Daghigh, S M; Mowlavi, A A

    2013-01-01

    Background and Objective: The most common intravascular brachytherapy sources include 32P, 188Re, 106Rh and 90Sr/90Y. In this research, skin absorbed dose for different covering materials in dealing with these sources were evaluated and the best covering material for skin protection and reduction of absorbed dose by radiation staff was recognized and recommended. Method: Four materials including polyethylene, cotton and two different kinds of plastic were proposed as skin covers and skin absorbed dose at different depths for each kind of the materials was calculated separately using the VARSKIN3 code. Results: The results suggested that for all sources, skin absorbed dose was minimized when using polyethylene. Considering this material as skin cover, maximum and minimum doses at skin surface were related to 90Sr/90Y and 106Rh, respectively. Conclusion: polyethylene was found the most effective cover in reducing skin dose and protecting the skin. Furthermore, proper agreement between the results of VARSKIN3 and other experimental measurements indicated that VRASKIN3 is a powerful tool for skin dose calculations when working with beta emitter sources. Therefore, it can be utilized in dealing with the issue of radiation protection. PMID:25505758

  14. Efficiency of Pm-147 direct charge radioisotope battery.

    PubMed

    Kavetskiy, A; Yakubova, G; Yousaf, S M; Bower, K; Robertson, J D; Garnov, A

    2011-05-01

    A theoretical analysis is presented here of the efficiency of direct charge radioisotope batteries based on the efficiency of the radioactive source, the system geometry, electrostatic repulsion of beta particles from the collector, the secondary electron emission, and backscattered beta particles from the collector. Efficiency of various design batteries using Pm-147 sources was experimentally measured and found to be in good agreement with calculations. The present approach can be used for predicting the efficiency for different designs of direct charge radioisotope batteries.

  15. Practical Applications of Radioactivity and Nuclear Radiations

    NASA Astrophysics Data System (ADS)

    Lowenthal, Gerhart; Airey, Peter

    2005-09-01

    1. Atoms, nuclides and radionuclides; 2. Units and standards for radioactivity and radiation dosimetry and rules for radiation protection; 3. Properties of radiations emitted from radionuclides; 4. Nuclear radiations from a user's perspective; 5. Ionising radiation detectors; 6. Radioactivity and countrate measurements and the presentation of results; 7. Industrial applications of radioisotopes and radiation; 8. Application of tracer technology to industry and the environment; 9. Radionuclides to protect the environment.

  16. Practical Applications of Radioactivity and Nuclear Radiations

    NASA Astrophysics Data System (ADS)

    Lowenthal, Gerhart; Airey, Peter

    2001-08-01

    1. Atoms, nuclides and radionuclides; 2. Units and standards for radioactivity and radiation dosimetry and rules for radiation protection; 3. Properties of radiations emitted from radionuclides; 4. Nuclear radiations from a user's perspective; 5. Ionising radiation detectors; 6. Radioactivity and countrate measurements and the presentation of results; 7. Industrial applications of radioisotopes and radiation; 8. Application of tracer technology to industry and the environment; 9. Radionuclides to protect the environment.

  17. Reliability of Radioisotope Stirling Convertor Linear Alternator

    NASA Technical Reports Server (NTRS)

    Shah, Ashwin; Korovaichuk, Igor; Geng, Steven M.; Schreiber, Jeffrey G.

    2006-01-01

    Onboard radioisotope power systems being developed and planned for NASA s deep-space missions would require reliable design lifetimes of up to 14 years. Critical components and materials of Stirling convertors have been undergoing extensive testing and evaluation in support of a reliable performance for the specified life span. Of significant importance to the successful development of the Stirling convertor is the design of a lightweight and highly efficient linear alternator. Alternator performance could vary due to small deviations in the permanent magnet properties, operating temperature, and component geometries. Durability prediction and reliability of the alternator may be affected by these deviations from nominal design conditions. Therefore, it is important to evaluate the effect of these uncertainties in predicting the reliability of the linear alternator performance. This paper presents a study in which a reliability-based methodology is used to assess alternator performance. The response surface characterizing the induced open-circuit voltage performance is constructed using 3-D finite element magnetic analysis. Fast probability integration method is used to determine the probability of the desired performance and its sensitivity to the alternator design parameters.

  18. Implanted artificial heart with radioisotope power source.

    PubMed

    Shumakov, V I; Griaznov, G M; Zhemchuzhnikov, G N; Kiselev, I M; Osipov, A P

    1983-02-01

    An atomic artificial heart for orthotopic implantation was developed with the following characteristics: volume, 1.2 L; weight, 1.5 kg; radioisotope power, 45 W; operating life, up to 5 years; hemodynamics, similar to natural hemodynamics. The artificial heart includes a thermal drive with systems for regulating power, feeding steam into the cylinders, return of the condensate to the steam generator, and delivery of power to the ventricles and heat container. The artificial heart is placed in an artificial pericardium partially filled with physiologic solution. It uses a steam engine with two operating cylinders that separately drive the left and right ventricles. There is no electronic control system in the proposed design. The operation of the heat engine is controlled, with preservation of autoregulation by the vascular system of the body. The separate drives for the ventricles is of primary importance as it provides for operation of the artificial heart through control of cardiac activity by venous return. Experimental testing on a hydromechanical bench demonstrated effective autoregulation.

  19. Some geophysical considerations in radioisotope dating applications

    NASA Astrophysics Data System (ADS)

    Hayes, Robert

    2016-03-01

    Radioisotope dating only assumes radioactive decay laws are taking place allowing closed form solutions to be obtained in generating a sample date estimate. To be discussed in this work is the isotopic distribution expected in geological samples due to mass diffusion superimposed on that from simple radioactive decay. By taking into consideration the isotope effect (differential mass diffusion rates) when measuring isotopic ratios from very old samples, the distribution dependency will cause a bias if isotopic diffusion rates are not identical throughout a material (or at least across the boundaries of all samples measured). The isotope effect being that isotopes having a smaller atomic mass will diffuse faster in a medium than will their heavier counterparts causing concentration gradients of their ratios even when there are no contributions from radioactive decay which will tend to bias all sample ages (slopes of the isochron) to have a more linear distribution. The application to Sr/Rb dating is evaluated and shown to result in expected age overestimates. Suggested methods to test for this effect along with sample preparation techniques to minimize it are discussed. Special thanks the NCSU Nuclear Engineering Department.

  20. Development of Water Target for Radioisotope Production

    NASA Astrophysics Data System (ADS)

    Tripp, Nathan

    2011-10-01

    Ongoing studies of plant physiology at TUNL require a supply of nitrogen-13 for use as a radiotracer. Production of nitrogen-13 using a water target and a proton beam follows the nuclear reaction 16-O(p,a)13-N. Unfortunately the irradiation of trace amounts of oxygen-18 within a natural water target produces fluorine-18 by the reaction 18-O(p, n)18-F. The presence of this second radioisotope reduces the efficacy of nitrogen-13 as a radiotracer. Designing a natural water target for nitrogen-13 production at TUNL required the design of several new systems to address the problems inherent in nitrogen-13 production. A heat exchanger cools the target water after irradiation within the target cell. The resulting improved thermal regulation of the target water prevents the system from overheating and minimizes the effect of the cavitations occurring within the target. Alumina pellets within a scrubbing unit remove the fluorine-18 contamination from the irradiated water. The modular design of the water target apparatus makes the system highly adaptable, allowing for easy reuse and adaptation of the different components into future projects. The newly designed and constructed water target should meet the current and future needs of TUNL researchers in the production of nitrogen-13. This TUNL REU project was funded in part by a grant from the National Science Foundation (NSF) NSF-PHY-08-51813.

  1. Light-weight radioisotope heater impact tests

    SciTech Connect

    Reimus, M.A.H.; Rinehart, G.H.; Herrera, A.

    1998-12-31

    The light-weight radioisotope heater unit (LWRHU) is a {sup 238}PuO{sub 2}-fueled heat source designed to provide one thermal watt in each of various locations on a spacecraft. Los Alamos National Laboratory designed, fabricated, and safety tested the LWRHU. The heat source consists of a hot-pressed {sup 238}PuO{sub 2} fuel pellet, a Pt-30Rh vented capsule, a pyrolytic graphite insulator, and a fineweave-pierced fabric graphite aeroshell assembly. To compare the performance of the LWRHUs fabricated for the Cassini mission with the performance of those fabricated for the Galileo mission, and to determine a failure threshold, two types of impact tests were conducted. A post-reentry impact test was performed on one of 180 flight-quality units produced for the Cassini mission and a series of sequential impact tests using simulant-fueled LWRHU capsules were conducted respectively. The results showed that deformation and fuel containment of the impacted Cassini LWRHU was similar to that of a previously tested Galileo LWRHU. Both units sustained minimal deformation of the aeroshell and fueled capsule; the fuel was entirely contained by the platinum capsule. Sequential impacting, in both end-on and side-on orientations, resulted in increased damage with each subsequent impact. Sequential impacting of the LWRHU appears to result in slightly greater damage than a single impact at the final impact velocity of 50 m/s.

  2. Radioisotopic heater units warm an interplanetary spacecraft

    SciTech Connect

    Franco-Ferreira, E.A.; Rinehart, G.H.

    1998-01-01

    The Cassini orbiter and Huygens probe, which were successfully launched on October 15, 1997, constitute NASA`s last grand-scale interplanetary mission of this century. The mission, which consists of a four-year, close-up study of Saturn and its moons, begins in July 2004 with Cassini`s 60 orbits of Saturn and about 33 fly-bys of the large moon Titan. The Huygens probe will descend and land on Titan. Investigations will include Saturn`s atmosphere, its rings and its magnetosphere. The atmosphere and surface of Titan and other icy moons also will be characterized. Because of the great distance of Saturn from the sun, some of the instruments and equipment on both the orbiter and the probe require external heaters to maintain their temperature within normal operating ranges. These requirements are met by Light Weight Radioisotope Heater Units (LWRHUs) designed, fabricated and safety tested at Los Alamos National Laboratory, New Mexico. An improved gas tungsten arc welding procedure lowered costs and decreased processing time for heat units for the Cassini spacecraft.

  3. Implanted artificial heart with radioisotope power source.

    PubMed

    Shumakov, V I; Griaznov, G M; Zhemchuzhnikov, G N; Kiselev, I M; Osipov, A P

    1983-02-01

    An atomic artificial heart for orthotopic implantation was developed with the following characteristics: volume, 1.2 L; weight, 1.5 kg; radioisotope power, 45 W; operating life, up to 5 years; hemodynamics, similar to natural hemodynamics. The artificial heart includes a thermal drive with systems for regulating power, feeding steam into the cylinders, return of the condensate to the steam generator, and delivery of power to the ventricles and heat container. The artificial heart is placed in an artificial pericardium partially filled with physiologic solution. It uses a steam engine with two operating cylinders that separately drive the left and right ventricles. There is no electronic control system in the proposed design. The operation of the heat engine is controlled, with preservation of autoregulation by the vascular system of the body. The separate drives for the ventricles is of primary importance as it provides for operation of the artificial heart through control of cardiac activity by venous return. Experimental testing on a hydromechanical bench demonstrated effective autoregulation. PMID:6838394

  4. Intravascular photoacoustic imaging at 35 and 80 MHz

    PubMed Central

    Li, Xiang; Wei, Wei; Shung, K. Kirk

    2012-01-01

    Abstract. The catheter-based intravascular photoacoustic (IVPA) imaging for diagnosing atherosclerosis, which can provide optical absorption contrast of the arterial wall besides acoustic scattering contrast from the conventional intravascular ultrasound (IVUS) imaging, has been intensively researched recently. The resolution of IVPA is determined by the frequency bandwidth of an ultrasonic transducer. Higher resolution can be achieved by increasing the transducer’s working frequency and bandwidth. We introduce IVPA imaging at 35 and 80 MHz by using newly designed integrated IVUS/IVPA probes. This is the first time IVPA has been achieved as high as 80 MHz. Six-micrometer tungsten wires were imaged to evaluate the probes’ spatial resolutions and beam patterns. Healthy rabbit aorta was imaged in vitro. Imaging results show that IVPA has superior contrast over IVUS in identifying the arterial wall, and IVPA at 80 MHz demonstrates extraordinary resolution (35 μm) compared to 35 MHz. PMID:23224004

  5. Thyroid Storm Complicated by Bicytopenia and Disseminated Intravascular Coagulation

    PubMed Central

    Tokushima, Yoshinori; Sakanishi, Yuta; Nagae, Kou; Tokushima, Midori; Tago, Masaki; Tomonaga, Motosuke; Yoshioka, Tsuneaki; Hyakutake, Masaki; Sugioka, Takashi; Yamashita, Shu-ichi

    2014-01-01

    Patient: Male, 23 Final Diagnosis: Thyroid storm Symptoms: Delirium • diarrhea • fever • hypertension • hyperventilation • tachycardia • weight loss Medication: — Clinical Procedure: — Specialty: Endocrinology and Metabolic Objective: Unusual clinical course Background: The clinical presentation of thyroid storm includes fever, tachycardia, hypertension, and neurological abnormalities. It is a serious condition with a high mortality rate. Furthermore, some other complications affect the clinical course of thyroid storm. Although it is reported that prognosis is poor when thyroid storm is complicated by disseminated intravascular coagulation syndrome (DIC) and leukopenia, reports of such cases are rare. Case Report: A 23-year-old man presented with delirium, high pyrexia, diarrhea, and weight loss of 18 kg over 2 months. According to the criteria of Burch and Wartofsky, he was diagnosed with thyroid storm on the basis of his symptom-complex and laboratory data that confirmed the presence of hyperthyroidism. Investigations also found leukopenia, thrombocytopenia, and disseminated intravascular coagulation, all of which are very rare complications of thyroid storm. We successfully treated him with combined therapy including anti-thyroid medication, despite leukopenia. Conclusions: Early diagnosis and treatment are essential in ensuring a good outcome for patients with this rare combination of medical problems. PMID:25072662

  6. [Disseminated intravascular coagulation. Case series and literature review].

    PubMed

    Del Carpio-Orantes, Luis; García-Ortiz, Jorge José

    2014-01-01

    INTRODUCCIÓN: la coagulación intravascular diseminada es una entidad caracteriza por activación de la cascada de la coagulación y fibrinólisis endógena, que puede provocar la muerte. Nuestros objetivos fueron identificar la incidencia de coagulación intravascular diseminada, sus agentes etiológicos y la correlación entre la puntuación de la escala Apache II y la propuesta por la Sociedad Internacional de Trombosis y Hemostasia para el diagnóstico de esta entidad. MÉTODOS: estudio retrospectivo, observacional y descriptivo de pacientes atendidos en una unidad de cuidados intensivos en un periodo de 17 meses. Se analizó etiología, edad, sexo, conteo de plaquetas, coagulograma, niveles de fibrinógeno sérico y cuantificación del dímero D. Se calculó la puntuación de la escala propuesta por la Sociedad Internacional de Trombosis y Hemostasia y de la escala APACHE II.

  7. A short contemporary history of disseminated intravascular coagulation.

    PubMed

    Levi, Marcel; van der Poll, Tom

    2014-11-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic intravascular activation of coagulation, leading to a widespread deposition of fibrin in the circulation. There is ample experimental and pathological evidence that the fibrin deposition contributes to multiple organ failure. The massive and ongoing activation of coagulation may result in depletion of platelets and coagulation factors, which may cause bleeding (consumption coagulopathy). The syndrome of DIC is well known in the medical literature for centuries, although a more precise description of the underlying mechanisms had to await the 20th century. Initial ideas on a role of the contact activation system as the primary trigger for the systemic activation of coagulation as well as a presumed hyperfibrinolytic response in DIC have been found to be misconceptions. Experimental and clinical evidence now indicate that the initiation of coagulation in DIC is caused by tissue factor expression, which in combination with downregulated physiological anticoagulant pathways and impaired fibrinolysis leads to widespread fibrin deposition. In addition, an extensive bidirectional interaction between coagulation and inflammation may further contribute to the pathogenesis of DIC.

  8. Fatal Cryocrystalglobulinemia With Intravascular and Renal Tubular Crystalline Deposits.

    PubMed

    DeLyria, Paul A; Avedschmidt, Sarah E; Yamada, Chisa; Farkash, Evan A

    2016-05-01

    Cryocrystalglobulinemia is a rare variant of cryoglobulinemia in which monoclonal immunoglobulins self-assemble into crystalline arrays. We report a case of a 53-year-old man who presented with systemic thrombotic microangiopathy causing multiorgan failure, including decreased kidney, lung, and gastrointestinal function; skin necrosis; and mental status changes. Skin and kidney biopsy specimens showed intravascular thrombi, along with intravascular, intratubular, and periglomerular crystalline deposits. Typical morphologic features of cryoglobulinemia, such as a leukocytoclastic vasculitis and pseudothrombi, were absent. Spindled crystals precipitated in the cryoglobulin assay, and immunofixation showed them to be composed of monoclonal immunoglobulin G κ light chains. Ultrastructural analysis demonstrated deposits to have an array-like substructure. The patient was successfully treated with a combination of plasmapheresis, steroids, and bortezomib, but experienced a relapse and died 12 months after his initial diagnosis. Cryocrystalglobulinemia causes significant morbidity and mortality and should be classified as a monoclonal gammopathy of renal significance when it occurs in patients not meeting diagnostic criteria for multiple myeloma. PMID:26775022

  9. Development of catheters for combined intravascular ultrasound and photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Karpiouk, Andrei B.; Wang, Bo; Emelianov, Stanislav Y.

    2009-02-01

    Coronary atherosclerosis is a complex disease accompanied by the development of plaques in the arterial wall. Since the vulnerability of the plaques depends on their composition, the appropriate treatment of the arteriosclerosis requires a reliable characterization of the plaques' geometry and content. The intravascular ultrasound (IVUS) imaging is capable of providing structural details of the plaques as well as some functional information. In turn, more functional information about the same plaques can be obtained from intravascular photoacoustic (IVPA) images since the optical properties of the plaque's components differ from that of their environment. The combined IVUS/IVPA imaging is capable of simultaneously detecting and differentiating the plaques, thus determining their vulnerability. The potential of combined IVUS/IVPA imaging has already been demonstrated in phantoms and ex-vivo experiments. However, for in-vivo or clinical imaging, an integrated IVUS/IVPA catheter is required. In this paper, we introduce two prototypes of integrated IVUS/IVPA catheters for in-vivo imaging based on a commercially available single-element IVUS imaging catheter. The light delivery systems are developed using multimode optical fibers with custom-designed distal tips. Both prototypes were tested and compared using an arterial mimicking phantom. The advantages and limitations of both designs are discussed. Overall, the results of our studies suggest that both designs of integrated IVUS/IVPA catheter have a potential for in-vivo IVPA/IVUS imaging of atherosclerotic plaques.

  10. High speed intravascular photoacoustic imaging of atherosclerotic arteries (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Piao, Zhonglie; Ma, Teng; Qu, Yueqiao; Li, Jiawen; Yu, Mingyue; He, Youmin; Shung, K. Kirk; Zhou, Qifa; Kim, Chang-Seok; Chen, Zhongping

    2016-02-01

    Cardiovascular disease is the leading cause of death in the industrialized nations. Accurate quantification of both the morphology and composition of lipid-rich vulnerable atherosclerotic plaque are essential for early detection and optimal treatment in clinics. In previous works, intravascular photoacoustic (IVPA) imaging for detection of lipid-rich plaque within coronary artery walls has been demonstrated in ex vivo, but the imaging speed is still limited. In order to increase the imaging speed, a high repetition rate laser is needed. In this work, we present a high speed integrated IVPA/US imaging system with a 500 Hz optical parametric oscillator laser at 1725 nm. A miniature catheter with 1.0 mm outer diameter was designed with a 200 μm multimode fiber and an ultrasound transducer with 45 MHz center frequency. The fiber was polished at 38 degree and enclosed in a glass capillary for total internal reflection. An optical/electrical rotary junction and pull-back mechanism was applied for rotating and linearly scanning the catheter to obtain three-dimensional imaging. Atherosclerotic rabbit abdominal aorta was imaged as two frame/second at 1725 nm. Furthermore, by wide tuning range of the laser wavelength from 1680 nm to 1770 nm, spectroscopic photoacoustic analysis of lipid-mimicking phantom and an human atherosclerotic artery was performed ex vivo. The results demonstrated that the developed IVPA/US imaging system is capable for high speed intravascular imaging for plaque detection.

  11. Dominant neurologic symptomatology in intravascular large B-cell lymphoma.

    PubMed

    Kubisova, K; Martanovic, P; Sisovsky, V; Tomleinova, Z; Steno, A; Janega, P; Rychly, B; Babal, P

    2016-01-01

    Intravascular large B-cell lymphoma (IVLBCL) is a rare variant of extranodal large B-cell lymphoma and it is characterized by selective intravascular proliferation of malignant cells. Typical features of the disease include aggressive behavior, rapid and frequently fatal course. Clinical picture is non-specific and heterogeneous, depending on the affected organ. It is not uncommon that this unique type of lymphoma is diagnosed post mortem. Herein, we report two cases of IVLBCL with neurologic symptomatology. In our clinical study patient 1 was an 80-year-old male with mixed paraparesis of lower extremities and difficulties with sphincter control. Patient 2 (56-year-old male) had vision malfunction, mental status changes and defect in phatic and motor functions. In both cases definite diagnosis was established by histological examination of necroptic material. We propose to include IVLBCL in differential diagnostic considerations in patients presenting with gradually impairing neurological status and spinal cord damage of unknown etiology (Fig. 2, Ref. 9). PMID:27546361

  12. Dual-element needle transducer for intravascular ultrasound imaging

    PubMed Central

    Yoon, Sangpil; Kim, Min Gon; Williams, Jay A.; Yoon, Changhan; Kang, Bong Jin; Cabrera-Munoz, Nestor; Shung, K. Kirk; Kim, Hyung Ham

    2015-01-01

    Abstract. A dual-element needle transducer for intravascular ultrasound imaging has been developed. A low-frequency element and a high-frequency element were integrated into one device to obtain images which conveyed both low- and high-frequency information from a single scan. The low-frequency element with a center frequency of 48 MHz was fabricated from the single crystal form of lead magnesium niobate-lead titanate solid solution with two matching layers (MLs) and the high frequency element with a center frequency of 152 MHz was fabricated from lithium niobate with one ML. The measured axial and lateral resolutions were 27 and 122  μm, respectively, for the low-frequency element, and 14 and 40  μm, respectively, for the high-frequency element. The performance of the dual-element needle transducer was validated by imaging a tissue-mimicking phantom with lesion-mimicking area, and ex vivo rabbit aortas in water and rabbit whole blood. The results suggest that a low-frequency element effectively provides depth resolved images of the whole vessel and its adjacent tissue, and a high-frequency element visualizes detailed structure near the surface of the lumen wall in the presence of blood within the lumen. The advantages of a dual-element approach for intravascular imaging are also discussed. PMID:26158118

  13. Focused intravascular ultrasonic probe using dimpled transducer elements.

    PubMed

    Chen, Y; Qiu, W B; Lam, K H; Liu, B Q; Jiang, X P; Zheng, H R; Luo, H S; Chan, H L W; Dai, J Y

    2015-02-01

    High-frequency focused intravascular ultrasonic probes were fabricated in this study using dimple technique based on PMN-PT single crystal and lead-free KNN-KBT-Mn ceramic. The center frequency, bandwidth, and insertion loss of the PMN-PT transducer were 34 MHz, 75%, and 22.9 dB, respectively. For the lead-free probe, the center frequency, bandwidth, and insertion loss were found to be 40 MHz, 72%, and 28.8 dB, respectively. The ultrasonic images of wire phantom and vessels with good resolution were obtained to evaluate the transducer performance. The -6 dB axial and lateral resolutions of the PMN-PT probe were determined to be 58 μm and 131 μm, respectively. For the lead-free probe, the axial and lateral resolutions were found to be 44 μm and 125 μm, respectively. These results suggest that the mechanical dimpling technique has good potential in preparing focused transducers for intravascular ultrasound applications. PMID:25108608

  14. The syndrome of pneumococcemia, disseminated intravascular coagulation and asplenia.

    PubMed Central

    Kingston, M E; MacKenzie, C R

    1979-01-01

    A 58-year-old man who survived an episode of fulminant pneumococcal septicemia with disseminated intravascular coagulation had undergone splenectomy 23 years previously. In the literature there are 25 reported cases of fulminant septicemia and disseminated intravascular coagulation associated with asplenia in adults (excluding cases in which corticosteroid or immunosuppressive therapy was given). The pneumococcus was responsible for all of these cases as well. The mortality in this series was more than 90%, and death occurred within 24 hours of presentation at hospital in almost 70% of the fatal cases and was associated with high-density bacteremia and adrenal hemorrhage. Gram-staining of the buffy coat of the peripheral blood or the exudate from purpuric skin lesions was carried out in only 6 of the 26 cases but yielded positive results in all but 1. It is concluded that a diagnosis of septicemia in asplenic adults can be established within a short time of presentation on the basis of statistical probability and the results of Gram-staining of the peripheral blood and exudate from the skin lesions. Prevention appears to be the cornerstone of management because of the variable interval from splenectomy to the onset of the syndrome and the high mortality. Images FIG. 1 PMID:38002

  15. Comparative analysis of 11 different radioisotopes for palliative treatment of bone metastases by computational methods

    SciTech Connect

    Guerra Liberal, Francisco D. C. E-mail: adriana-tavares@msn.com; Tavares, Adriana Alexandre S. E-mail: adriana-tavares@msn.com; Tavares, João Manuel R. S.

    2014-11-01

    Purpose: Throughout the years, the palliative treatment of bone metastases using bone seeking radiotracers has been part of the therapeutic resources used in oncology, but the choice of which bone seeking agent to use is not consensual across sites and limited data are available comparing the characteristics of each radioisotope. Computational simulation is a simple and practical method to study and to compare a variety of radioisotopes for different medical applications, including the palliative treatment of bone metastases. This study aims to evaluate and compare 11 different radioisotopes currently in use or under research for the palliative treatment of bone metastases using computational methods. Methods: Computational models were used to estimate the percentage of deoxyribonucleic acid (DNA) damage (fast Monte Carlo damage algorithm), the probability of correct DNA repair (Monte Carlo excision repair algorithm), and the radiation-induced cellular effects (virtual cell radiobiology algorithm) post-irradiation with selected particles emitted by phosphorus-32 ({sup 32}P), strontium-89 ({sup 89}Sr), yttrium-90 ({sup 90}Y ), tin-117 ({sup 117m}Sn), samarium-153 ({sup 153}Sm), holmium-166 ({sup 166}Ho), thulium-170 ({sup 170}Tm), lutetium-177 ({sup 177}Lu), rhenium-186 ({sup 186}Re), rhenium-188 ({sup 188}Re), and radium-223 ({sup 223}Ra). Results: {sup 223}Ra alpha particles, {sup 177}Lu beta minus particles, and {sup 170}Tm beta minus particles induced the highest cell death of all investigated particles and radioisotopes. The cell survival fraction measured post-irradiation with beta minus particles emitted by {sup 89}Sr and {sup 153}Sm, two of the most frequently used radionuclides in the palliative treatment of bone metastases in clinical routine practice, was higher than {sup 177}Lu beta minus particles and {sup 223}Ra alpha particles. Conclusions: {sup 223}Ra and {sup 177}Lu hold the highest potential for palliative treatment of bone metastases of all

  16. [Potential radiation hazard in nuclear medicine].

    PubMed

    Guilabert, Nadine; Ricard, Marcel; Chamoulaud, Karen; Mazelier, Carole; Schlumberger, Martin

    2015-01-01

    Nuclear medicine uses unsealed radioisotopes. The potential radiation hazards depend on the amount of radioactivity administered and the type of radionucleide. Thus, radiation safety instructions will minimize radiation exposure and contamination as low as reasonably achievable. National nuclear safety authority requires rules, regulations and exposure limits for both patients and workers. Good practices and training staff contribute to optimize the radioprotection. PMID:25842441

  17. Use of water-equivalent plastic scintillator for intravascular brachytherapy dosimetry.

    PubMed

    Geso, M; Robinson, N; Schumer, W; Williams, K

    2004-03-01

    Beta irradiation has recently been investigated as a possible technique for the prevention of restenosis in intravascular brachytherapy after balloon dilatation or stent implantation. Present methods of beta radiation dosimetry are primarily conducted using radiochromic film. These film dosimeters exhibit limited sensitivity and their characteristics differ from those of tissue, therefore the dose measurement readings require correction factors to be applied. In this work a novel, mini-size (2 mm diameter by 5 mm long) dosimeter element fabricated from Organic Plastic Scintillator (OPS) material was employed. Scintillation photon detection is accomplished using a precision photodiode and innovative signal amplification and processing techniques, rather than traditional photomultiplier tube methods. A significant improvement in signal to noise ratio, dynamic range and stability is achieved using this set-up. In addition, use of the non-saturating organic plastic scintillator material as the detector enables the dosimeter to measure beta radiation at very close distances to the source. In this work the plastic scintillators have been used to measure beta radiation dose at distances of less than 1 mm from an Sr-90 cardiovascular brachytherapy source having an activity of about 2.1 GBq beta radiation levels for both depth-distance and longitudinal profile of the source pellet chain, both in air and in liquid water, are measured using this system. The data obtained is compared with results from Monte Carlo simulation technique (MCNP 4B). Plastic scintillator dosimeter elements, when used in conjunction with photodiode detectors may prove to be useful dosimeters for cardiovascular brachytherapy beta sources, or other applications where precise near-source field dosimetry is required. The system described is particularly useful where measurement of actual dose rate in real time, a high level of stability and repeatability, portability, and immediate access to results are

  18. Gadolinium neutron capture brachytherapy (GdNCB), a new treatment method for intravascular brachytherapy

    SciTech Connect

    Enger, Shirin A.; Rezaei, Arash; Munck af Rosenschoeld, Per; Lundqvist, Hans

    2006-01-15

    Restenosis is a major problem after balloon angioplasty and stent implantation. The aim of this study is to introduce gadolinium neutron capture brachytherapy (GdNCB) as a suitable modality for treatment of stenosis. The utility of GdNCB in intravascular brachytherapy (IVBT) of stent stenosis is investigated by using the GEANT4 and MCNP4B Monte Carlo radiation transport codes. To study capture rate, Kerma, absorbed dose and absorbed dose rate around a Gd-containing stent activated with neutrons, a 30 mm long, 5 mm diameter gadolinium foil is chosen. The input data is a neutron spectrum used for clinical neutron capture therapy in Studsvik, Sweden. Thermal neutron capture in gadolinium yields a spectrum of high-energy gamma photons, which due to the build-up effect gives an almost flat dose delivery pattern to the first 4 mm around the stent. The absorbed dose rate is 1.33 Gy/min, 0.25 mm from the stent surface while the dose to normal tissue is in order of 0.22 Gy/min, i.e., a factor of 6 lower. To spare normal tissue further fractionation of the dose is also possible. The capture rate is relatively high at both ends of the foil. The dose distribution from gamma and charge particle radiation at the edges and inside the stent contributes to a nonuniform dose distribution. This will lead to higher doses to the surrounding tissue and may prevent stent edge and in-stent restenosis. The position of the stent can be verified and corrected by the treatment plan prior to activation. Activation of the stent by an external neutron field can be performed days after catherization when the target cells start to proliferate and can be expected to be more radiation sensitive. Another advantage of the nonradioactive gadolinium stent is the possibility to avoid radiation hazard to personnel.

  19. Radiation

    NASA Video Gallery

    Outside the protective cocoon of Earth's atmosphere, the universe is full of harmful radiation. Astronauts who live and work in space are exposed not only to ultraviolet rays but also to space radi...

  20. Radiation imaging system

    DOEpatents

    Immel, David M.; Bobbit, III, John T.; Plummer, Jean R.; Folsom, Matthew D.; Serrato, Michael G.

    2016-03-22

    A radiation imaging system includes a casing and a camera disposed inside the casing. A first field of view through the casing exposes the camera to light from outside of the casing. An image plate is disposed inside the casing, and a second field of view through the casing to the image plate exposes the image plate to high-energy particles produced by a radioisotope outside of the casing. An optical reflector that is substantially transparent to the high-energy particles produced by the radioisotope is disposed with respect to the camera and the image plate to reflect light to the camera and to allow the high-energy particles produced by the radioisotope to pass through the optical reflector to the image plate.

  1. Radiation imaging system

    DOEpatents

    Bobbitt, III, John T.; Immel, David M.; Folsom, Matthew D.; Plummer, Jean R.; Serrato, Michael G.

    2016-06-28

    A radiation imaging system includes a casing and a camera disposed inside the casing. A first field of view through the casing exposes the camera to light from outside of the casing. An image plate is disposed inside the casing, and a second field of view through the casing to the image plate exposes the image plate to high-energy particles produced by a radioisotope outside of the casing. An optical reflector that is substantially transparent to the high-energy particles produced by the radioisotope is disposed with respect to the camera and the image plate to reflect light to the camera and to allow the high-energy particles produced by the radioisotope to pass through the optical reflector to the image plate.

  2. Coated particle fuel for radioisotope power systems (RPSs) and radioisotope heater units (RHUs)

    NASA Astrophysics Data System (ADS)

    Sholtis, Joseph A.; Lipinski, Ronald J.; El-Genk, Mohamed S.

    1999-01-01

    Coated particle fuel offers great promise for advanced radioisotope power systems (RPSs) and radioisotope heater units (RHUs) being pursued for future U.S. solar system exploration missions. Potential benefits of this fuel include improved design flexibility and materials compatibility, enhanced safety and performance, and reduced specific mass and volume. This paper describes and discusses coated particle fuel, with emphasis on its applicability, attributes, and potential benefits to future RPSs and RHUs. Additionally, this paper identifies further analyses and verification testing that should be conducted before a commitment is made to fully develop this fuel. Efforts to date indicate there is every reason to believe that the potential benefits of coated particle fuel to future RPSs and RHUs can be demonstrated with a modest, phased analytical and verification test effort. Thus, developmental risk appears minimal, while the potential benefits are substantial. If coated particle fuel is pursued and ultimately developed successfully, it could revolutionize the design and space use of future RPSs and RHUs.

  3. ARAS: an automated radioactivity aliquoting system for dispensing solutions containing positron-emitting radioisotopes

    DOE PAGESBeta

    Dooraghi, Alex A.; Carroll, Lewis; Collins, Jeffrey; van Dam, R. Michael; Chatziioannou, Arion F.

    2016-03-09

    Automated protocols for measuring and dispensing solutions containing radioisotopes are essential not only for providing a safe environment for radiation workers but also to ensure accuracy of dispensed radioactivity and an efficient workflow. For this purpose, we have designed ARAS, an automated radioactivity aliquoting system for dispensing solutions containing positron-emitting radioisotopes with particular focus on fluorine-18 (18F). The key to the system is the combination of a radiation detector measuring radioactivity concentration, in line with a peristaltic pump dispensing known volumes. Results show the combined system demonstrates volume variation to be within 5 % for dispensing volumes of 20 μLmore » or greater. When considering volumes of 20 μL or greater, the delivered radioactivity is in agreement with the requested amount as measured independently with a dose calibrator to within 2 % on average. In conclusion, the integration of the detector and pump in an in-line system leads to a flexible and compact approach that can accurately dispense solutions containing radioactivity concentrations ranging from the high values typical of [18F]fluoride directly produced from a cyclotron (~0.1-1 mCi μL-1) to the low values typical of batches of [18F]fluoride-labeled radiotracers intended for preclinical mouse scans (~1-10 μCi μL-1).« less

  4. A shielded storage and processing facility for radioisotope thermoelectric generator heat source production

    SciTech Connect

    Sherrell, D.L.

    1992-06-01

    This report discusses a shielded storage rack which has been installed as part of the Radioisotope Power Systems Facility (RPSF) at the US Department of Energy`s (DOE) Hanford Site in Washington State. The RPSF is designed to replace an existing facility at DOE`s Mound Site near Dayton, Ohio, where General Purpose Heat Source (GPHS) modules are currently assembled and installed into Radioisotope Thermoelectric Generators (RTG). The overall design goal of the RPSF is to increase annual production throughput, while at the same time reducing annual radiation exposure to personnel. The shield rack design successfully achieved this goal for the Module Reduction and Monitoring Facility (MRMF), which process and stores assembled GPHS modules, prior to their installation into RTGS. The shield rack design is simple and effective, with the result that background radiation levels within Hanford`s MRMF room are calculated at just over three percent of those typically experienced during operation of the existing MRMF at Mound, despite the fact that Hanford`s calculations assume five times the GPHS inventory of that assumed for Mound.

  5. A shielded storage and processing facility for radioisotope thermoelectric generator heat source production

    SciTech Connect

    Sherrell, D.L.

    1992-06-01

    This report discusses a shielded storage rack which has been installed as part of the Radioisotope Power Systems Facility (RPSF) at the US Department of Energy's (DOE) Hanford Site in Washington State. The RPSF is designed to replace an existing facility at DOE's Mound Site near Dayton, Ohio, where General Purpose Heat Source (GPHS) modules are currently assembled and installed into Radioisotope Thermoelectric Generators (RTG). The overall design goal of the RPSF is to increase annual production throughput, while at the same time reducing annual radiation exposure to personnel. The shield rack design successfully achieved this goal for the Module Reduction and Monitoring Facility (MRMF), which process and stores assembled GPHS modules, prior to their installation into RTGS. The shield rack design is simple and effective, with the result that background radiation levels within Hanford's MRMF room are calculated at just over three percent of those typically experienced during operation of the existing MRMF at Mound, despite the fact that Hanford's calculations assume five times the GPHS inventory of that assumed for Mound.

  6. Concept for a radioisotope powered dual mode lunar rover

    NASA Technical Reports Server (NTRS)

    Elliott, John O.; Schriener, Timothy M.; Coste, Keith

    2006-01-01

    Over three decades ago, the Apollo missions manifestly demonstrated the value of a lunar rover to expand the exploration activities of lunar astronauts. The stated plan of the new Vision for Space Exploration to establish a permanent presence on the moon in the next decades gives new impetus to providing long range roving and exploration capability in support of the siting, construction, and maintenance of future human bases. The incorporation of radioisotope power systems and telerobotic capability in the design has the potential to significantly expand the capability of such a rover, allowing continuous operation during the full lunar day/night cycle, as well as enabling exploration in permanently shadowed regions that may be of interest to humans for the resources they may hold. This paper describes a concept that builds on earlier studies originated in the Apollo program for a Dual Mode (crewed and telerobotic) Lunar Roving Vehicle (DMLRV). The goal of this vehicle would be to provide a multipurpose infrastructure element and remote science platform for the exploration of the moon. The DMLRV would be essential for extending the productivity of human exploration crews, and would provide a unique capability for diverse long-range, long-duration science exploration between human visits. With minimal reconfiguration this vehicle could also provide the basic platform to support a range of site survey and preparation activities in anticipation of the establishment of a permanent human presence on the moon. A conceptual design is presented for the DMLRV, including discussion of mission architecture, vehicle performance, representative science payload accommodation, and equipment and crew radiation considerations.

  7. Intravascular ultrasound imaging of peripheral arteries as an adjunct to balloon angioplasty and atherectomy.

    PubMed

    Korogi, Y; Hirai, T; Takahashi, M

    1996-01-01

    This article reviews many of the applications of intravascular ultrasound (US) imaging for peripheral arterial diseases. In vitro studies demonstrate an excellent correlation between ultrasound measurements of lumen and plaque cross-sectional area compared with histologic sections. In vivo clinical studies reveal the enhanced diagnostic capabilities of this technology compared with angiography. Intravascular US imaging can provide valuable information on the degree, eccentricity, and histologic type of stenosis before intervention, and on the morphological changes in the arterial wall and the extent of excision after intervention. Intravascular US may also serve as a superior index for gauging the diameter of balloon, stent, laser probe, and/or atherectomy catheter appropriate for a proposed intervention. Significant new insights into the mechanisms of balloon angioplasty and atherectomy have been established by intravascular US findings. Intravascular US imaging has been shown to be a more accurate method than angiography for determining the cross-sectional area of the arterial lumen, and for assessing severity of stenosis. Quantitative assessment of the luminal cross-sectional area after the balloon dilatation should be more accurate than angiography as intimal tears or dissections produced by the dilatation may not be accurately evaluated with angiography. At the present time, intravascular US is still a controversial imaging technique. Outcome studies are currently being organized to assess the clinical value and cost effectiveness of intravascular ultrasound in the context of these interventional procedures. PMID:8653738

  8. Light-Weight Radioisotope Heater Unit

    SciTech Connect

    Schock, Alfred

    1981-04-01

    DOE is developing a new generation of radioisotope-fueled 1-watt heaters, for initial use on NASA's upcoming Galileo and International Solar-Polar Missions. Each heater must contain passive safety provisions to ensure fuel retention under all credible accident conditions. Initial design reviews raised some concern about the accuracy of the predicted peak reenetry temperature, and about the adequacy of the safety margin under certain unlikely - but not impossible-reentry modes. Of particular concern was the possile release of the accumulated helium inventory from the fuel during the reentry heat pulse, and the potential effect of enhanced heat conduction due to helium buildup in gaps. The latter problem had not been addressed in previous studies. Fairchild carried out a large number of reentry thermal analyses to resolve the analytical uncertainties, and proposed design changes to reduce the thermal coupling between the aeroshell and the fuel capsule. For the computed reentry temperature history of the modified design, the rate of helium buildup in the gaps was analyzed. The analysis accounted for temperature-dependent helium diffusion through the fuel pellet and for leakage to space through the permeable aeroshell. It showed that most of the helium inventory leaves the fuel during reentry, but that it never reaches a continuum pressure in the gaps, and therefore has no significant thermal effect. Under these conditions, the Fairchild-modified design provides ample safety margin against clad failure, even for very unlikely reenty trajectories. The modified design was successfully vibration-tested and was subsequently adopted by the project. Cross Reference CID #8517. There are two copies in the file.

  9. Methods of Fabricating Scintillators with Radioisotopes for Beta Battery Applications

    NASA Technical Reports Server (NTRS)

    Rensing, Noa M.; Squillante, Michael R.; Tieman, Timothy C.; Higgins, William; Shiriwadkar, Urmila

    2013-01-01

    to low-energy photons to electric current). The geometric advantage partially offsets this as well, since the absorption depth of high-energy beta radiation is much larger than the depth of a p-n junction. Thus, in a p-n junction device, much of the radiation is absorbed far away from the junction, and the electron- hole pairs are not all effectively collected. In contrast, with a transparent scintillator the radiation can be converted to light in a larger volume, and all of the light can be collected in the active region of the photodiode. Finally, the new device is more practical because it can be used at much higher power levels without unduly shortening its lifetime. While the crystal structure of scintillators is also subject to radiation damage, their performance is far more tolerant of defects than that of semiconductor junctions. This allows the scintillator- based approach to use both higher energy isotopes and larger quantities of the isotopes. It is projected that this technology has the potential to produce a radioisotope battery with up to twice the efficiency of presently used systems.

  10. Daily intakes of naturally occurring radioisotopes in typical Korean foods.

    PubMed

    Choi, Min-Seok; Lin, Xiu-Jing; Lee, Sun Ah; Kim, Wan; Kang, Hee-Dong; Doh, Sih-Hong; Kim, Do-Sung; Lee, Dong-Myung

    2008-08-01

    The concentrations of naturally occurring radioisotopes ((232)Th, (228)Th, (230)Th, (228)Ra, (226)Ra, and (40)K) in typical Korean foods were evaluated. The daily intakes of these radioisotopes were calculated by comparing concentrations in typical Korean foods and the daily consumption rates of these foods. Daily intakes were as follows: (232)Th, 0.00-0.23; (228)Th, 0.00-2.04; (230)Th, 0.00-0.26; (228)Ra, 0.02-2.73; (226)Ra, 0.01-4.37 mBq/day; and (40)K, 0.01-5.71 Bq/day. The total daily intake of the naturally occurring radioisotopes measured in this study from food was 39.46 Bq/day. The total annual internal dose resulting from ingestion of radioisotopes in food was 109.83 muSv/y, and the radioisotope with the highest daily intake was (40)K. These values were same level compiled in other countries.

  11. Local lymph node assay with non-radioisotope alternative endpoints.

    PubMed

    Suda, Akiko; Yamashita, Masahiro; Tabei, Mitsuyuki; Taguchi, Kazuhiko; Vohr, Hans-Werner; Tsutsui, Naohisa; Suzuki, Ritsuyoshi; Kikuchi, Katsuaki; Sakaguchi, Keisuke; Mochizuki, Kouki; Nakamura, Kazuichi

    2002-08-01

    The local lymph node assay has recently been accepted by regulatory agencies as a stand-alone alternate method for predicting allergic contact dermatitis. To compare the sensitivity of non-radioisotope methods with that of the standard assay, we determined if these modified methods would affect evaluation of sensitization potency. For this reason, we used 2,4-dinitrochlorobenzene (DNCB) and benzocaine for different sensitizing criteria. Female CBA mice were treated for 3 days with a test compound or vehicle applied to each side of both ears. Bilateral auricular lymph node proliferative activity was assessed by the following endpoints with incorporation of 3H-methyl thymidine (3H-TdR), bromodeoxyuridine (BrdU) in vivo, and BrdU ex vivo, IL-2 production, and proliferating cell nuclear antigen (PCNA) expression. Ear thickness was also tested. The strong sensitizer DNCB was detectable by any of the non-radioisotope endpoints as well as by radioisotope-dependent standard assay. On the other hand, when evaluating the weak sensitizer benzocaine, significant changes were evident in BrdU incorporation ex vivo and in vivo, and IL-2 production. We believe that these non-radioisotope methods can assess allergic contact dermatitis caused by chemicals even in the laboratory, where it can be difficult to handle radioisotopes.

  12. NASA's Advanced Radioisotope Power Conversion Technology Development Status

    NASA Technical Reports Server (NTRS)

    Anderson, David J.; Sankovic, John; Wilt, David; Abelson, Robert D.; Fleurial, Jean-Pierre

    2007-01-01

    NASA's Advanced Radioisotope Power Systems (ARPS) project is developing the next generation of radioisotope power conversion technologies that will enable future missions that have requirements that cannot be met by either photovoltaic systems or by current radioisotope power systems (RPSs). Requirements of advanced RPSs include high efficiency and high specific power (watts/kilogram) in order to meet future mission requirements with less radioisotope fuel and lower mass so that these systems can meet requirements for a variety of future space applications, including continual operation surface missions, outer-planetary missions, and solar probe. These advances would enable a factor of 2 to 4 decrease in the amount of fuel required to generate electrical power. Advanced RPS development goals also include long-life, reliability, and scalability. This paper provides an update on the contractual efforts under the Radioisotope Power Conversion Technology (RPCT) NASA Research Announcement (NRA) for research and development of Stirling, thermoelectric, and thermophotovoltaic power conversion technologies. The paper summarizes the current RPCT NRA efforts with a brief description of the effort, a status and/or summary of the contractor's key accomplishments, a discussion of upcoming plans, and a discussion of relevant system-level benefits and implications. The paper also provides a general discussion of the benefits from the development of these advanced power conversion technologies and the eventual payoffs to future missions (discussing system benefits due to overall improvements in efficiency, specific power, etc.).

  13. NASA Radioisotope Power System Program - Technology and Flight Systems

    NASA Technical Reports Server (NTRS)

    Sutliff, Thomas J.; Dudzinski, Leonard A.

    2009-01-01

    NASA sometimes conducts robotic science missions to solar system destinations for which the most appropriate power source is derived from thermal-to-electrical energy conversion of nuclear decay of radioactive isotopes. Typically the use of a radioisotope power system (RPS) has been limited to medium and large-scale missions, with 26 U,S, missions having used radioisotope power since 1961. A research portfolio of ten selected technologies selected in 2003 has progressed to a point of maturity, such that one particular technology may he considered for future mission use: the Advanced Stirling Converter. The Advanced Stirling Radioisotope Generator is a new power system in development based on this Stirling cycle dynamic power conversion technology. This system may be made available for smaller, Discovery-class NASA science missions. To assess possible uses of this new capability, NASA solicited and funded nine study teams to investigate unique opportunities for exploration of potential destinations for small Discovery-class missions. The influence of the results of these studies and the ongoing development of the Advanced Stirling Radioisotope Generator system are discussed in the context of an integrated Radioisotope Power System program. Discussion of other and future technology investments and program opportunities are provided.

  14. Intravascular ultrasound and optical coherence tomography imaging of coronary atherosclerosis.

    PubMed

    Costopoulos, Charis; Brown, Adam J; Teng, Zhongzhao; Hoole, Stephen P; West, Nick E J; Samady, Habib; Bennett, Martin R

    2016-01-01

    Invasive imaging modalities, in particular intravascular ultrasound (IVUS) and optical coherence tomography (OCT), have become established tools for the in vivo study of coronary atherosclerosis. Their use in clinical studies has confirmed histopathological observations that certain important plaque features, such as thin fibrous caps and large lipid cores, are associated with plaque rupture, the precipitating event for the majority of myocardial infarctions. Serial imaging studies have also successfully been used for the evaluation of potential disease modifying pharmacological agents. Recent prospective IVUS studies have confirmed specific baseline imaging features associated with subsequent adverse clinical outcomes, although absolute event rates were too low for clinical utility. Development of hybrid IVUS-OCT imaging or integration of novel techniques, including near-infrared spectroscopy, plaque structural and endothelial shear stress, have great potential to improve our current ability to identify and stratify atheromatous plaques at risk of rupture.

  15. Acute renal failure and intravascular hemolysis following henna ingestion.

    PubMed

    Qurashi, Hala E A; Qumqumji, Abbas A A; Zacharia, Yasir

    2013-05-01

    The powder of henna plant (Lawsonia inermis Linn.) is extensively used as a decorative skin paint for nail coloring and as a hair dye. Most reports of henna toxicity have been attributed to adding a synthetic dye para-phenylenediamine (PPD). PPD is marketed as black henna added to natural henna to accentuate the dark color and shorten the application time. PPD toxicity is well known and extensively reported in medical literature. We report a case of a young Saudi male who presented with characteristic features of acute renal failure and intravascular hemolysis following ingestion of henna mixture. Management of PPD poisoning is only supportive and helpful only if instituted early. Diagnosis requires a high degree of clinical suspicion, as the clinical features are quite distinctive. PMID:23640630

  16. Mathematical Modeling of Intravascular Blood Coagulation under Wall Shear Stress.

    PubMed

    Rukhlenko, Oleksii S; Dudchenko, Olga A; Zlobina, Ksenia E; Guria, Georgy Th

    2015-01-01

    Increased shear stress such as observed at local stenosis may cause drastic changes in the permeability of the vessel wall to procoagulants and thus initiate intravascular blood coagulation. In this paper we suggest a mathematical model to investigate how shear stress-induced permeability influences the thrombogenic potential of atherosclerotic plaques. Numerical analysis of the model reveals the existence of two hydrodynamic thresholds for activation of blood coagulation in the system and unveils typical scenarios of thrombus formation. The dependence of blood coagulation development on the intensity of blood flow, as well as on geometrical parameters of atherosclerotic plaque is described. Relevant parametric diagrams are drawn. The results suggest a previously unrecognized role of relatively small plaques (resulting in less than 50% of the lumen area reduction) in atherothrombosis and have important implications for the existing stenting guidelines.

  17. Basic studies on intravascular low-intensity laser therapy

    NASA Astrophysics Data System (ADS)

    Liu, Timon Cheng-Yi; Duan, Rui; Wang, Shuang-Xi; Liu, Jiang; Cui, Li-Ping; Jin, Hua; Liu, Song-Hao

    2006-09-01

    Intravascular low intensity laser therapy (ILILT) was originally put forward in USA in 1982, but popularized in Russia in 1980s and in China in 1990s, respectively. A randomized placebo-controlled study has shown ILILT clinical efficacy in patients suffering from rheumatoid arthritis. As Chinese therapeutic applications of ILILT were the most widely in the world, its basic research, such as intracellular signal transduction research, blood research in vitro, animal blood research in vivo, human blood research in vivo and traditional Chinese medicine research, was also very progressive in China. Its basic studies will be reviewed in terms of the biological information model of photobiomodulation in this paper. ILILT might work in view of its basic studies, but the further randomized placebo-controlled trial and the further safety research should be done.

  18. [Traumatic abruption of the placenta with disseminated intravascular coagulation].

    PubMed

    Benz, R; Malär, A-U; Benz-Wörner, J; Scherer, M; Hodel, M; Gähler, A; Haberthür, C; Konrad, C

    2012-10-01

    Trauma in pregnancy is infrequent and a systematic primary strategy constitutes a real challenge for the interdisciplinary team. With a high fetal mortality rate and a substantial maternal mortality rate traumatic placental abruption is a severe emergency which every anesthetist should be aware of. After hemodynamic stabilization of the mother and control of the viability of the fetus the therapy of traumatic placental abruption consists mostly of an immediate caesarean section. Coagulopathy by depletion of coagulation factors as well as disseminated intravascular coagulation (DIC) have to be expected and consequently a massive blood loss must be anticipated. Thrombelastography provides assistance for fast differential diagnosis and goal-directed treatment of the disturbed sections of the coagulation cascade.

  19. Thrombocytopenia and thrombosis in disseminated intravascular coagulation (DIC).

    PubMed

    Kitchens, Craig S

    2009-01-01

    Disseminated intravascular coagulation (DIC) is the physiologic result of pathologic overstimulation of the coagulation system. Despite multiple triggers, a myriad of laboratory abnormalities, and a clinical presentation ranging from gross hemostatic failure to life-threatening thrombosis, or even both simultaneously, a simplified clinical approach augmented by a few readily available tests allows prompt identification of the process and elucidation of treatment opportunities. Platelet counts in DIC may be low, especially in acute sepsis-associated DIC, yet increased in malignancy-associated chronic DIC. Thrombotic risk is not a function of the platelet count, and thrombocytopenia does not protect the patient from thrombosis. The stratification of both thrombotic risk and hemorrhagic risk will be addressed.

  20. Disseminated intravascular coagulation in obstetric and gynecologic disorders.

    PubMed

    Montagnana, Martina; Franchi, Massimo; Danese, Elisa; Gotsch, Francesca; Guidi, Gian Cesare

    2010-06-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by a massive, widespread, and ongoing activation of the coagulation system, secondary to a variety of clinical conditions. Many obstetric complications, such as abruptio placentae, amniotic fluid embolism, endotoxin sepsis, retained dead fetus, post-hemorrhagic shock, hydatidiform mole, and gynecologic malignancies, might trigger DIC. In these gynecologic and obstetric settings, DIC is usually associated with high mortality and morbidity rates. No single laboratory test is sensitive or specific enough to diagnose DIC definitively, but it can be diagnosed by using a combination of multiple clinical and laboratory tests that reflect the pathophysiology of the syndrome. At present, the therapeutical approach to pregnancy- and gynecologic-related DIC comprises the specific and aggressive treatment of the underlying disease, eventually followed by a supportive blood product replacement therapy and restoration of physiological anticoagulant pathways. This article reviews the etiopathogenesis, clinical manifestations, laboratory diagnosis, and therapy of pregnancy- and gynecologic-related DIC.

  1. Potential diagnostic markers for disseminated intravascular coagulation of sepsis.

    PubMed

    Iba, Toshiaki; Ito, Takashi; Maruyama, Ikuro; Jilma, Bernd; Brenner, Thorsten; Müller, Marcella C A; Juffermans, Nicole P; Thachil, Jecko

    2016-03-01

    Disseminated intravascular coagulation (DIC) is an acquired thrombo-haemorrhagic disorder which arises in clinical scenarios like sepsis, trauma and malignancies. The clinic-laboratory diagnosis of DIC is made in a patient who develops the combination of laboratory abnormalities in the appropriate clinical scenario. The most common laboratory parameters in this setting have been the clotting profile, platelet count, serum fibrinogen and fibrin degradation markers. These tests had the advantage that they could be performed easily and in most laboratories. However, with the better understanding of the pathophysiology of DIC, in recent years, more specific tests have been suggested to be useful in this setting. The newer tests can also prove to be useful in prognostication in DIC. In addition, they may provide assistance in the selection and monitoring of patients diagnosed with DIC.

  2. Adaptive Estimation of Intravascular Shear Rate Based on Parameter Optimization

    NASA Astrophysics Data System (ADS)

    Nitta, Naotaka; Takeda, Naoto

    2008-05-01

    The relationships between the intravascular wall shear stress, controlled by flow dynamics, and the progress of arteriosclerosis plaque have been clarified by various studies. Since the shear stress is determined by the viscosity coefficient and shear rate, both factors must be estimated accurately. In this paper, an adaptive method for improving the accuracy of quantitative shear rate estimation was investigated. First, the parameter dependence of the estimated shear rate was investigated in terms of the differential window width and the number of averaged velocity profiles based on simulation and experimental data, and then the shear rate calculation was optimized. The optimized result revealed that the proposed adaptive method of shear rate estimation was effective for improving the accuracy of shear rate calculation.

  3. Advanced Congestive Heart Failure Associated With Disseminated Intravascular Coagulopathy.

    PubMed

    Sarcon, Annahita; Liu, Xiaoli; Ton, David; Haywood, James; Hitchcock, Todd

    2015-01-01

    Background. Disseminated intravascular coagulopathy (DIC) is a complication of an underlying disease and not a primary illness. It is most commonly associated with sepsis, trauma, obstetrical complications, and malignancies. There are very few cases in the literature illustrating the association between DIC and congestive heart failure. Findings. In this report, we present a case of severe congestive heart failure, leading to biventricular thrombi and subsequently DIC. Conclusion. We suggest that the association between congestive heart failure and DIC is an underrecognized one. Congestive heart failure continues to remain a major cause of morbidity and mortality despite advances in medical therapies. Thus far, the precise role of coagulation factors in congestive heart failure is unknown. Further investigations are needed to elucidate the pathophysiology of congestive heart failure and coagulation factors.

  4. Analysis of gas composition of intravascular bubbles produced by decompression.

    PubMed

    Ishiyama, A

    1983-06-01

    The gas composition of intravascular bubbles produced by decompression was investigated in rabbits using gas chromatography. The animals were exposed to 8 ATA for 30 min. All samples of bubbles were taken from the animals under 0.2 ATA pressure gradient so that no air could enter the sampling system from the outside. The percentage of carbon dioxide in the bubbles tended to decrease at first and then increased with post-decompression time. On the other hand, the percentage of oxygen tended to change in the opposite manner. Actual analysis of bubbles in the living decompressed animals indicates that carbon dioxide may be an outstanding factor in the initiation and early growth of bubbles. In view of this, Haldane's classical maximum supersaturation limit for avoiding decompression sickness should be examined and possibly modified for gases other than nitrogen.

  5. Intravascular Myopericytoma in the Heel: Case Report and Literature Review

    PubMed Central

    Valero, José; Salcini, José L.; Gordillo, Luis; Gallart, José; González, David; Deus, Javier; Lahoz, Manuel

    2015-01-01

    Abstract Intravascular myopericytoma (IVMP), regarded as a variant of myopericytoma, is a rare tumor. Very few cases have been described, none in the foot. The first case of IVMP located in the heel of the foot is described in this article. A literature review is reported of all cases of IVMP published in the English literature. A 48-year-old man possessed an IVMP on the heel of the right foot. The physical examination and histopathological and ultrasound studies are described. The literature review yielded 5 cases of IVMP, 2 of which were in the thigh and 1 each in the oral mucosa, the periorbital region, and the leg. The possibility that these lesions may be malignant suggests that the histopathological study of vascular tumors should include immunohistochemical tests. PMID:25789958

  6. Mathematical Modeling of Intravascular Blood Coagulation under Wall Shear Stress

    PubMed Central

    Rukhlenko, Oleksii S.; Dudchenko, Olga A.; Zlobina, Ksenia E.; Guria, Georgy Th.

    2015-01-01

    Increased shear stress such as observed at local stenosis may cause drastic changes in the permeability of the vessel wall to procoagulants and thus initiate intravascular blood coagulation. In this paper we suggest a mathematical model to investigate how shear stress-induced permeability influences the thrombogenic potential of atherosclerotic plaques. Numerical analysis of the model reveals the existence of two hydrodynamic thresholds for activation of blood coagulation in the system and unveils typical scenarios of thrombus formation. The dependence of blood coagulation development on the intensity of blood flow, as well as on geometrical parameters of atherosclerotic plaque is described. Relevant parametric diagrams are drawn. The results suggest a previously unrecognized role of relatively small plaques (resulting in less than 50% of the lumen area reduction) in atherothrombosis and have important implications for the existing stenting guidelines. PMID:26222505

  7. Impact of Intravascular Hemolysis in Malaria on Liver Dysfunction

    PubMed Central

    Dey, Sumanta; Bindu, Samik; Goyal, Manish; Pal, Chinmay; Alam, Athar; Iqbal, Mohd. Shameel; Kumar, Rahul; Sarkar, Souvik; Bandyopadhyay, Uday

    2012-01-01

    We have investigated the impact of persistent intravascular hemolysis on liver dysfunction using the mouse malaria model. Intravascular hemolysis showed a positive correlation with liver damage along with the increased accumulation of free heme and reactive oxidants in liver. Hepatocytes overinduced heme oxygenase-1 (HO-1) to catabolize free heme in building up defense against this pro-oxidant milieu. However, in a condition of persistent free heme overload in malaria, the overactivity of HO-1 resulted in continuous transient generation of free iron to favor production of reactive oxidants as evident from 2′,7′-dichlorofluorescein fluorescence studies. Electrophoretic mobility shift assay documented the activation of NF-κB, which in turn up-regulated intercellular adhesion molecule 1 as evident from chromatin immunoprecipitation studies. NF-κB activation also induced vascular cell adhesion molecule 1, keratinocyte chemoattractant, and macrophage inflammatory protein 2, which favored neutrophil extravasation and adhesion in liver. The infiltration of neutrophils correlated positively with the severity of hemolysis, and neutrophil depletion significantly prevented liver damage. The data further documented the elevation of serum TNFα in infected mice, and the treatment of anti-TNFα antibodies also significantly prevented neutrophil infiltration and liver injury. Deferoxamine, which chelates iron, interacts with free heme and bears antioxidant properties that prevented oxidative stress, NF-κB activation, neutrophil infiltration, hepatocyte apoptosis, and liver damage. Furthermore, the administration of N-acetylcysteine also prevented NF-κB activation, neutrophil infiltration, hepatocyte apoptosis, and liver damage. Thus, hepatic free heme accumulation, TNFα release, oxidative stress, and NF-κB activation established a link to favor neutrophil infiltration in inducing liver damage during hemolytic conditions in malaria. PMID:22696214

  8. An intravascular MRI contrast agent based on Gd(DO3A-Lys) for tumor angiography.

    PubMed

    Yang, Chang-Tong; Chandrasekharan, Prashant; He, Tao; Poh, Zihan; Raju, Anandhkumar; Chuang, Kai-Hsiang; Robins, Edward G

    2014-01-01

    An intravascular MRI contrast agent Gd(DO3A-Lys), Gadolinium(III) (2,2',2″-(10-(3-(5-benzamido-6-methoxy-6-oxohexylamino)-3-oxopropyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetate), has been studied for tumor angiography based on its high relaxivity and long blood half-life. The preparation procedures of the contrast agent have been modified in order to achieve higher yield and improve the synthetic reproducibility. High relaxivity of Gd(DO3A-Lys) has been confirmed by measurements at 3 T, 7 T and 9.4 T magnetic fields. The relaxivity-dependent albumin binding study indicated that Gd(DO3A-Lys) partially bound to albumin protein. In vitro cell viability in HK2 cell indicated low cytotoxicity of Gd(DO3A-Lys) up to 1.2 mM [Gd] concentration. In vivo toxicity studies demonstrated no toxicity of Gd(DO3A-Lys) on kidney tissues up to 0.2 mM [Gd]. While the toxicity on liver tissue was not observed at low dosage (1.0 mM [Gd]), Gd(DO3A-Lys) cause certain damage on hepatic tissue at high dosage (2.0 mM [Gd]). The DO3A-Lys has been labeled with (68)Ga radioisotope for biodistribution studies. (68)Ga(DO3A-Lys) has high uptake in both HT1080 and U87MG xenograft tumors, and has high accumulation in blood. Contrast-enhanced MR angiography (CE-MRA) in mice bearing U87MG xenograft tumor demonstrated that Gd(DO3A-Lys) could enhance vascular microenvironment around the tumor, and displays promising characteristics of an MRI contrast agent for tumor angiography.

  9. Intravascular Large B-Cell Lymphoma Coexisting with an Ovarian Carcinoma.

    PubMed

    Uchiyama, Tomoko; Nakamine, Hirokazu; Morita, Kohei; Itami, Hiroe; Nakai, Tokiko; Takano, Masato; Takeda, Maiko; Hatakeyama, Kinta; Takahama, Junko; Tanase, Yasuhito; Kobayashi, Hiroshi; Ohbayashi, Chiho

    2016-01-01

    We report an incidental case of intravascular large B-cell lymphoma (IVLBCL) coexisting with an ovarian carcinoma in a 76-year-old woman. She visited our hospital with difficulty in defecation. Magnetic resonance imaging and computerized tomography scan revealed a solid and cystic mass probably arising from the left ovary. Gross examination of the tumor obtained by an exploratory surgery showed a solid area in a simple cyst. The ovarian tumor was diagnosed as a high-grade serous carcinoma (HGSC). Early in the post-operative course, this patient developed fever of unknown origin with central nervous system manifestations. Magnetic resonance imaging of the brain showed multiple space-occupying lesions. When we reviewed the histological sections, atypical lymphocytes were found in the lumina of small vessels of almost the entire ovary. These cells were positive for CD20 and CD79a by immunohistochemistry. A diagnosis of IVLBCL coexisting with HGSC was finally made. Although radiation therapy for brain lesions was performed and rituximab was administered, she died two months after the operation. To the best of our knowledge, this is the first case of IVLBCL incidentally identified in HGSC through microscopic examination. This case serves to create awareness of the rare event where IVLBCL may involve the ovary of patients who also have carcinoma in the organ. PMID:27334860

  10. Intravascular Ultrasound Guidance for Transjugular Intrahepatic Portosystemic Shunt Procedure in a Swine Model

    SciTech Connect

    Kew, Jacqueline; Davies, Roger P.

    2004-01-15

    A new method is described for guiding hepato-portalvenous puncture using a longitudinal side-view intravascular ultrasound(L-IVUS) transducer to assist in the performance of transjugularintrahepatic portosystemic shunt (TIPS) in three Australian swine.Simultaneous L-IVUS with an AcuNav (registered) 5-10 MHz 10 Fr transducer(Acuson Corporation, Mountain View, CA, USA) and fluoroscopy guidance was used to image and monitor the hepatic to portal venous puncture,dilatation of the tract, and deployment of the TIPS stent. Flow through the shunt could be demonstrated with both L-IVUS and angiography. TIPS was successful in all swine. The time for portal vein puncture once the target portal vein was identified was reduced at each attempt. The number of portal vein puncture attempts was 2, 1, and 1. No post-procedural complication was evident. L-IVUS-guided TIPS is practical and has the potential to improve safety by permitting simultaneous ultrasound and fluoroscopic imaging of the needle and target vascular structures. This technique allows for a more streamlined approach to TIPS, decreasing the fluoroscopic time (hence,decreasing the radiation exposure to the staff and patient) and anesthetic time. In addition, there are improved safety benefits obviating the need for wedged portography, facilitating avoidance of bile duct and hepatic arterial puncture, and minimizing hepatic injury by decreasing liver capsular puncture and the attendant risks.

  11. Image-based dosimetry of an implanted radioactive stent using intravascular ultrasound

    NASA Astrophysics Data System (ADS)

    Peterson, Stephen W.

    Angioplasty has become an increasingly popular and effective treatment for heart disease. Unfortunately, restenosis, a cellular and biological reaction to the procedure, has hindered its effectiveness. Two of the most successful methods of inhibiting restenosis are radiation and stents. The combination of these two components, radioactive stents, is not as common as some of the other methods, yet still has potential of slowing restenosis. Investigation into source characteristics and artery wall radiobiology may illuminate some possible solutions to the problems of restenosis. This work has developed a calculational method to look at in-vivo images of implanted stents and determine the dose to the artery walls in order to test different source characteristics. The images are Intravascular Ultrasound (IVUS) cross-sectional slices of the stent and the artery. From these images, it is possible to determine the implanted stent structure. The pieces of the stent are identified in the images and modeled in a Monte Carlo simulation, using MCNP4c3. The simulation results were combined with the images to give three-dimensional absolute dose contours of the stent. The absolute dose values were verified using radiochromic film and 198Au-plated stents. This work was able to successfully verify the dose results and create a three-dimensional dose map of the implanted stent.

  12. Alveolar rhabdomyosarcoma with massive disseminated intravascular coagulopathy treated with systemic chemotherapy.

    PubMed

    Yoon, Byung Gyu; Baek, Hee Jo; Oh, Burm Seok; Han, Dong Kyun; Choi, Yoo Duk; Kook, Hoon

    2015-12-01

    It is uncommon for pediatric patients with rhabdomyosarcoma to present with clinical and/or laboratory features of disseminated intravascular coagulation (DIC). We report a case of metastatic alveolar rhabdomyosarcoma with severe bleeding because of DIC in a 13-year-old boy. He experienced persistent oozing at the site of a previous operation, gross hematuria, and massive epistaxis. Two weeks after initiating combination chemotherapy consisting of vincristine, doxorubicin, and cyclophosphamide, the patients' laboratory indications of DIC began to resolve. During this period, the patient received massive blood transfusion of a total of 311 units (26 units of red blood cells, 26 units of fresh frozen plasma, 74 units of platelet concentrates, 17 units of single donor platelets, and 168 units of cryoprecipitate), antithrombin-III and a synthetic protease inhibitor. Despite chemotherapy and radiation therapy, he died 1 year later because of disease progression. In children with metastatic rhabdomyosarcoma and massive DIC, prompt chemotherapy and aggressive supportive care is important to decrease malignancy-triggered procoagulant activities.

  13. High Efficiency Thermoelectric Radioisotope Power Systems

    NASA Technical Reports Server (NTRS)

    El-Genk, Mohamed; Saber, Hamed; Caillat, Thierry

    2004-01-01

    The work performed and whose results presented in this report is a joint effort between the University of New Mexico s Institute for Space and Nuclear Power Studies (ISNPS) and the Jet Propulsion Laboratory (JPL), California Institute of Technology. In addition to the development, design, and fabrication of skutterudites and skutterudites-based segmented unicouples this effort included conducting performance tests of these unicouples for hundreds of hours to verify theoretical predictions of the conversion efficiency. The performance predictions of these unicouples are obtained using 1-D and 3-D models developed for that purpose and for estimating the actual performance and side heat losses in the tests conducted at ISNPS. In addition to the performance tests, the development of the 1-D and 3-D models and the development of Advanced Radioisotope Power systems for Beginning-Of-Life (BOM) power of 108 We are carried out at ISNPS. The materials synthesis and fabrication of the unicouples are carried out at JPL. The research conducted at ISNPS is documented in chapters 2-5 and that conducted at JP, in documented in chapter 5. An important consideration in the design and optimization of segmented thermoelectric unicouples (STUs) is determining the relative lengths, cross-section areas, and the interfacial temperatures of the segments of the different materials in the n- and p-legs. These variables are determined using a genetic algorithm (GA) in conjunction with one-dimensional analytical model of STUs that is developed in chapter 2. Results indicated that when optimized for maximum conversion efficiency, the interfacial temperatures between various segments in a STU are close to those at the intersections of the Figure-Of-Merit (FOM), ZT, curves of the thermoelectric materials of the adjacent segments. When optimizing the STUs for maximum electrical power density, however, the interfacial temperatures are different from those at the intersections of the ZT curves, but

  14. Investigation of Miniaturized Radioisotope Thermionic Power Generation for General Use

    NASA Technical Reports Server (NTRS)

    Duzik, Adam J.; Choi, Sang H.

    2016-01-01

    Radioisotope thermoelectric generators (RTGs) running off the radioisotope Pu238 are the current standard in deep space probe power supplies. While reliable, these generators are very inefficient, operating at only approx.7% efficiency. As an alternative, more efficient radioisotope thermionic emission generators (RTIGs) are being explored. Like RTGs, current RTIGs concepts use exotic materials for the emitter, limiting applicability to space and other niche applications. The high demand for long-lasting mobile power sources would be satisfied if RTIGs could be produced inexpensively. This work focuses on exposing several common materials, such as Al, stainless steel, W, Si, and Cu, to elevated temperatures under vacuum to determine the efficiency of each material as inexpensive replacements for thermoelectric materials.

  15. Investigation of miniaturized radioisotope thermionic power generation for general use

    NASA Astrophysics Data System (ADS)

    Duzik, Adam J.; Choi, Sang H.

    2016-04-01

    Radioisotope thermoelectric generators (RTGs) running off the radioisotope Pu238 are the current standard in deep space probe power supplies. While reliable, these generators are very inefficient, operating at only ~7% efficiency. As an alternative, more efficient radioisotope thermionic emission generators (RTIGs) are being explored. Like RTGs, current RTIGs concepts use exotic materials for the emitter, limiting applicability to space and other niche applications. The high demand for long-lasting mobile power sources would be satisfied if RTIGs could be produced inexpensively. This work focuses on exposing several common materials, such as Al, stainless steel, W, Si, and Cu, to elevated temperatures under vacuum to determine the efficiency of each material as inexpensive replacements for thermoelectric materials.

  16. Hair radioactivity as a measure of exposure to radioisotopes

    NASA Technical Reports Server (NTRS)

    Strain, W. H.; Pories, W. J.; Fratianne, R. B.; Flynn, A.

    1972-01-01

    Since many radioisotopes accumulate in hair, this tropism was investigated by comparing the radioactivity of shaved with plucked hair collected from rats at various time intervals up to 24 hrs after intravenous injection of the ecologically important radioisotopes, iodine-131, manganese-54, strontium-85, and zinc-65. The plucked hair includes the hair follicles where biochemical transformations are taking place. The data indicate a slight surge of each radioisotpe into the hair immediately after injection, a variation of content of each radionuclide in the hair, and a greater accumulation of radioactivity in plucked than in shaved hair. These results have application not only to hair as a measure of exposure to radioisotopes, but also to tissue damage and repair at the hair follicle.

  17. Realistic Specific Power Expectations for Advanced Radioisotope Power Systems

    NASA Technical Reports Server (NTRS)

    Mason, Lee S.

    2006-01-01

    Radioisotope Power Systems (RPS) are being considered for a wide range of future NASA space science and exploration missions. Generally, RPS offer the advantages of high reliability, long life, and predictable power production regardless of operating environment. Previous RPS, in the form of Radioisotope Thermoelectric Generators (RTG), have been used successfully on many NASA missions including Apollo, Viking, Voyager, and Galileo. NASA is currently evaluating design options for the next generation of RPS. Of particular interest is the use of advanced, higher efficiency power conversion to replace the previous thermoelectric devices. Higher efficiency reduces the quantity of radioisotope fuel and potentially improves the RPS specific power (watts per kilogram). Power conversion options include Segmented Thermoelectric (STE), Stirling, Brayton, and Thermophotovoltaic (TPV). This paper offers an analysis of the advanced 100 watt-class RPS options and provides credible projections for specific power. Based on the analysis presented, RPS specific power values greater than 10 W/kg appear unlikely.

  18. Intravascular large B-cell lymphoma with hemophagocytic syndrome (Asian variant) in a Caucasian patient.

    PubMed

    Fung, Kar-Ming; Chakrabarty, Jennifer H; Kern, William F; Magharyous, Hany; Gehrs, Bradley C; Li, Shibo

    2012-01-01

    Intravascular lymphoma is an aggressive and extremely rare extranodal lymphoma with neoplastic lymphoid cells confined exclusively within intravascular spaces. The histopathologic findings are subtle due to the rarity of the neoplastic cells in blood vessels. Clinical presentations are non-specific and focal space-occupying lesions or lymphoadenopathy are always lacking. It is a diagnostic challenge. Secondary hemophagocytic syndrome is uncommon and is typically associated with infection, malignancy, and suppressed immune states. Intravascular lymphoma has a strong association with hemophagocytic syndrome in Asian patients, the so-called "Asian variant", but not in Western patients. We report a case of intravascular B-cell lymphoma in a Caucasian patient associated with secondary hemophagocytic syndrome. The patient was diagnosed by core liver biopsy and successfully treated. This case demonstrates the importance of high index of suspicion and astute histopathologic examination in recognition of this unusual clinical and pathologic combination.

  19. [The usefulness of intravascular echography during the percutaneous dilatation of aortic coarctation].

    PubMed

    Goicolea, F J; Macaya, C; Iñíguez, A; Alfonso, F; Hernández Antolín, R; Vila i Costa, I; Zamorano, J; Egocheaga, I; Zarco, P

    1992-01-01

    An intravascular ultrasound study was performed in a patient, to assess the anatomy of aortic coarctation and the results obtained after percutaneous dilation with a balloon catheter. Intravascular ultrasound imaging provides important additional information, not obtainable with other diagnostic procedures, regarding aortic wall structure and thickness. After balloon dilation, aortic disruption was clearly observed, accounting, together with the stretching of the outer layers of the aortic wall, for the increase in aortic luminal area. Intravascular ultrasound permitted also the accurate assessment of the improvement obtained. Intravascular imaging was clearly superior not only to conventional angiography, but also to transesophageal echocardiography in detecting the mechanism of dilation. We conclude that ultravascular ultrasound, with the additional information that it provides, may help in the selection of patients for percutaneous dilation of the coarctation as well as contributing to the identification of the mechanism of dilation.

  20. Radioisotopic methods for biological and medical research

    SciTech Connect

    Knoche, H.W.

    1991-01-01

    This book provides a theoretical basis for the effective and safe use of radioactive materials in research. Particular attention is given to the four major topic areas specified in NRC's license application forms: (1) principles and practices of radiation protection; (2) radioactivity measurement, standardization and monitoring techniques, and instruments; (3) mathematics and calculations basic to the use and measurement of radioactivity; (4) biological effects of radiation. Overview and background information, including a section reviewing nuclear physics, is used where needed throughout the text, and problem sets are included in many of the chapters. Appendices for physical constants and conversion factors and for answers to problems are added.

  1. Procurement of a fully licensed radioisotope thermoelectric generator transportation system

    SciTech Connect

    Adkins, H.E.; Bearden, T.E.

    1990-10-01

    A fully licensed transportation system for Radioisotope Thermoelectric Generators and Light-Weight Radioisotope Heater Units is currently being designed and built. The system will comply with all applicable US Department of Transportation regulations without the use of a DOE Alternative.'' The US Department of Transportation has special double containment'' requirements for plutonium. The system packaging uses a doubly contained bell jar'' concept. A refrigerated trailer is used for cooling the high-heat payloads. The same packaging is used for both high- and low-heat payloads. The system is scheduled to be available for use by mid-1992. 4 refs., 4 figs., 2 tabs.

  2. Procurement of a fully licensed radioisotope thermoelectric generator transportation system

    NASA Astrophysics Data System (ADS)

    Adkins, Harold E.; Bearden, Thomas E.

    1991-01-01

    A fully licensed transportation system for Radioisotope Thermoelectric Generators and Light-Weight Radioisotope Heater Units is currently being designed and built. The system will comply with all applicable U.S. Department of Transportation regulations without the use of a ``DOE Alternative.'' The U.S. Department of Transportation has special ``double containment'' requirements for plutonium. The system packaging uses a doubly contained ``bell jar'' concept. A refrigerated trailer is used for cooling the high-heat payloads. The same packaging is used for both high- and low-heat payloads. The system is scheduled to be available for use by mid-1992.

  3. Ablation response testing of simulated radioisotope power supplies

    NASA Astrophysics Data System (ADS)

    Lutz, Steven A.; Chan, Chris C.

    1994-05-01

    Results of an experimental program to assess the aerothermal ablation response of simulated radioisotope power supplies are presented. Full-scale general purpose heat source, graphite impact shell, and lightweight radioisotope heater unit test articles are all tested without nuclear fuel in simulated reentry environments. Convective stagnation heating, stagnation pressure, stagnation surface temperature, surface recession profile, and weight loss measurements are obtained for diffusion-limited and sublimation ablation conditions. The recession profile and weight loss measurements show an effect of surface features on the stagnation face. The surface features alter the local heating which in turn affects the local ablation.

  4. Synthesis and characterization of radioisotope nanospheres containing two gamma emitters.

    PubMed

    Jung, Jin-Hyuck; Jung, Sung-Hee; Kim, Sang-Ho; Choi, Seong-Ho

    2012-12-01

    Silica-coated gold-silver alloy nanospheres prepared by Stöber's method were irradiated in a nuclear reactor to prepare radioisotope nanospheres for use as radiotracers. The radioisotope nanospheres included two gamma nuclides: (i) Au-198, emitting major photons with 0.412 MeV and (ii) Ag-108, emitting photons with 0.434 and 0.633 MeV. The nanospheres shell and core diameters were 100-112 nm and 20-50 nm, respectively, depending on their preparation. The gamma-emitting nanospheres could be used as tracers in high-temperature petrochemical and refinery processes in which conventional organic radioactive labels will decompose.

  5. New trick for removal of intravascular retained foreign body: a case report and review of literature.

    PubMed

    Mousa, Albeir Y; Gill, Gurpreet; Aburahma, Ali F

    2014-01-01

    A 54-year-old male presented to the vascular service for an urgent inpatient consultation. During an infusaport removal, the catheter was accidentally disconnected and lost intravascularly within the left subclavian vein, with the tip still in the right ventricle. We report on a novel technique for removing such intravascular foreign bodies (FBs), which will add a valuable technical option to our existing armamentarium regarding intracorporeal FB removal.

  6. Effect of Inert Cover Gas on Performance of Radioisotope Stirling Space Power System

    SciTech Connect

    Carpenter, Robert; Kumar, V; Ore, C; Schock, Alfred

    2001-01-01

    This paper describes an updated Orbital design of a radioisotope Stirling power system and its predicted performance at the beginning and end of a six-year mission to the Jovian moon Europa. The design is based on General Purpose Heat Source (GPHS) modules identical to those previously developed and safety-qualified by the Department of Energy (DOE) which were successfully launched to Jupiter and Saturn by the Jet Propulsion Laboratory (JPL). In each generator, the heat produced by the decay of the Pu-238 isotope is converted to electric power by two free-piston Stirling engines and linear alternators developed by Stirling Technology Company (STC), and their rejected waste heat is transported to radiators by heat pipes. The principal difference between the proposed system design and previous Orbital designs (Or et al. 2000) is the thermal insulation between the heat source and the generator's housing. Previous designs had employed multifoil insulation, whereas the design described here employs Min-K-1800 thermal insulation. Such insulation had been successfully used by Teledyne and GE in earlier RTGs (Radioisotope Thermoelectric Generators). Although Min-K is a much poorer insulator than multifoil in vacuum and requires a substantially greater thickness for equivalent performance, it offers compensating advantages. Specifically it makes it possible to adjust the generator's BOM temperatures by filling its interior volume with inert cover gas. This makes it possible to meet the generator's BOM and EOM performance goals without exceeding its allowable temperature at the beginning of the mission.

  7. ULTRASONIC AND RADIOGRAPHIC IMAGING OF NIOBIUM TARGET CAPSULES FOR RADIOISOTOPE PRODUCTION

    SciTech Connect

    Bach, H. T.; Claytor, T. N.; Hunter, J. F.; Dozier, B. E.; Nortier, F. M.; Smith, D. M.; Lenz, J. W.; Moddrell, C.; Smith, P. A.

    2009-03-03

    In the case of proton-irradiated radioisotope production, niobium target capsules containing gallium are exposed to intense radiation, thermally induced stress, for extended periods. The structural integrity of the target capsules is of crucial importance for containing the accelerator-produced radioisotopes and target material. The capsule window should be as thin and transparent to the proton beam as possible, and preferably should not become significantly activated under proton irradiation. In addition, the material for the capsule needs to be as defect-free as possible. Niobium encapsulated gallium targets have a history of unpredictable failure under intense irradiation with 100 MeV protons. This study illustrates the utility of non-destructive testing in order to detect defects that may result in mechanical failure of the capsules during irradiation. Prior to this work, it was not known if the gallium initially wets the niobium capsule that encapsulates it, and if it does, it is not known to what degree. However, the imaging techniques used in this work show that local areas of wetting do occur. We used ultrasonic images from various lots of niobium capsule material to assess the integrity of the capsules. Digital radiography is also used to detect any voids in the gallium that will tend to cause local heating in the capsules.

  8. Effect of inert cover gas on performance of radioisotope Stirling space power system

    NASA Astrophysics Data System (ADS)

    Carpenter, R.; Kumar, V.; Or, C.; Schock, A.

    2001-02-01

    This paper describes an updated Orbital design of a radioisotope Stirling power system and its predicted performance at the beginning and end of a six-year mission to the Jovian moon Europa. The design is based on General Purpose Heat Source (GPHS) modules identical to those previously developed and safety-qualified by the Department of Energy (DOE) which were successfully launched on missions to Jupiter and Saturn by the Jet Propulsion Laboratory (JPL). In each generator, the heat produced by the decay of the Pu-238 isotope is converted to electric power by two free-piston Stirling engines and linear alternators developed by Stirling Technology Company (STC), and their rejected waste heat is transported to radiators by heat pipes. The principal difference between the proposed system design and previous Orbital designs (Or et al., 2000) is the thermal insulation between the heat source and the generator's housing. Previous designs had employed multifoil insulation, whereas the design described here employs Min-K-1800 thermal insulation. Such insulation had been successfully used by Teledyne and GE in earlier RTGs (Radioisotope Thermoelectric Generators). Although Min-K is a much poorer insulator than multifoil in vacuum and requires a substantially greater thickness for equivalent performance, it offers compensating advantages. Specifically it makes it possible to adjust the generator's BOM temperatures by filling its interior volume with inert cover gas. This makes it possible to meet the generator's BOM and EOM performance goals without exceeding its allowable temperature at the beginning of the mission. .

  9. The effects of radioisotopes used in nuclear medicine on diagnostic radioimmunoassay testing. Is there any significant interference

    SciTech Connect

    Riccio, J.A.; Maturani, D.; Wright, J.; Fleetwood, M.K. )

    1990-11-01

    The administration of radioisotopes for diagnostic nuclear medicine scans and therapeutic procedures is quite prevalent today. A period of interference with the counting of a radioimmunoassay (RIA) test may occur with the serum of a patient receiving an in vivo radionuclide that decays by gamma emission. Because the logistics of precounting all specimens may be cumbersome and prohibitive, it is important to determine the degree of this interference. In this study, the authors evaluate the potential interference of the most commonly used radioisotopes with RIA studies. For two months (March and August 1988) 10,650 patient serum specimens were counted for significant background gamma radiation before RIA testing. Forty-three patients, on whom 105 RIA tests were performed, were identified as having preassay gamma radiation in their serum. With the use of selective energy windows for each different interfering radionuclide, proportional determinations were made as to the amount of interfering gamma radiation spilling into the iodine 125 test marker window. It was shown that initial whole serum pretest gamma counts as high as 111,000 counts/minute did not significantly affect the results of the RIA. Because of the meticulous washing and decanting procedures required in modern RIA and the monoclonal nature of most antibodies used currently, it appears the degree of nonspecific binding of this potentially interfering radiation is minuscule. The energy level of cobalt 57, however, and many of the other commonly used radioisotopes, overlaps so closely that it is difficult to window for this interference. It is possible, therefore, that this distinction cannot be made and folate and vitamin B12 test systems using cobalt 57 markers may have to be routinely prescreened.

  10. Intravascular Large B-Cell Lymphoma: A Difficult Diagnostic Challenge.

    PubMed

    Khan, Maria S; McCubbin, Mark; Nand, Sucha

    2014-01-01

    Case Presentation. A 69-year-old Hispanic male, with a past history of diabetes and coronary disease, was admitted for fever, diarrhea, and confusion of 4 weeks duration. Physical examination showed a disoriented patient with multiple ecchymoses, possible ascites, and bilateral scrotal swelling. Hemoglobin was 6.7, prothrombin time (PT) 21.4 seconds with international normalized ratio 2.1, partial thromboplastin time (PTT) 55.6 seconds, fibrin split 10 µg/L, and lactate dehydrogenase (LDH) 1231 IU/L. Except for a positive DNA test for Epstein-Barr virus (EBV) infection, extensive diagnostic workup for infections, malignancy, or a neurological cause was negative. Mixing studies revealed a nonspecific inhibitor of PT and PTT but Factor VIII levels were normal. The patient was empirically treated with antibiotics but developed hypotension and died on day 27 of admission. At autopsy, patient was found to have intravascular diffuse large B-cell lymphoma involving skin, testes, lung, and muscles. The malignant cells were positive for CD20, CD791, Mum-1, and Pax-5 and negative for CD3, CD5, CD10, CD30, and Bcl-6. The malignant cells were 100% positive for Ki-67. Discussion. Intravascular large cell B-cell lymphoma (IVLBCL) is rare form of diffuse large B-cell lymphoma and tends to proliferate within small blood vessels, particularly capillaries and postcapillary venules. The cause of its affinity for vascular bed remains unknown. In many reports, IVLBCL was associated with HIV, HHV8, and EBV infections. The fact that our case showed evidence of EBV infection lends support to the association of this diagnosis to viral illness. The available literature on this subject is scant, and in many cases, the diagnosis was made only at autopsy. The typical presentation of this disorder is with B symptoms, progressive neurologic deficits, and skin findings. Bone marrow, spleen, and liver are involved in a minority of patients. Nearly all patients have elevated LDH, and about 65% are

  11. Intravascular papillary endothelial hyperplasia: histomorphological and immunohistochemical features

    PubMed Central

    2013-01-01

    Background Intravascular papillary endothelial hyperplasia (IPEH) is a benign intravascular process with features mimicking other benign and malignant vascular proliferations. IPEH lesions predominate in the head-neck region and the extremities. The characteristic histomorphological feature of IPEH is a papillary structure covered with hyperplastic endothelial cells within the vascular lumen. It is critical that this clinically benign lesion should not be mistaken for well-differentiated vascular tumors. In addition to the characteristic histological features, other useful diagnostic features included the intra-luminal location of the lesion, an intimate association with the organizing thrombus, the absence of necrosis, cellular pleomorphism, and mitotic activity. In addition, immunohistochemistry may indicate the vascular origin and proliferative index. In this study, we evaluated histomorphological and immunohistochemical findings (CD31, CD34, FVIII, type IV collagen, SMA, MSA, CD105, and Ki-67 staining) of ten IPEH cases. Methods Ten IPEH cases were re-examined for a panel of histomorphological and immunohistochemical features. CD31, CD34, FVIII, Type IV collagen, SMA and MSA antibodies utilized for immunohistochemical analysis. The histomorphological and immunohistochemical findings were evaluated by two independent pathologists using light microscopy. Results All ten cases involved intraluminal lesions with characteristic features of IPEH. All ten cases (100%) were stained positive for CD31 and CD34. The degree of staining with FVIII, type IV collagen, SMA, and MSA was variable. Conclusion In this series of specimens, CD31 and CD34 were the most sensitive markers indicating the vascular origin of the lesion. Staining for the other vascular markers (FVIII, type IV collagen, SMA and MSA) was variable. Different maturation degrees of lesions may account for the variation in immunohistochemical staining. Few previous investigations evaluated a wide range of

  12. Optimization of commercial scale photonuclear production of radioisotopes

    NASA Astrophysics Data System (ADS)

    Bindu, K. C.; Harmon, Frank; Starovoitova, Valeriia N.; Stoner, Jon; Wells, Douglas P.

    2013-04-01

    Photonuclear production of radioisotopes driven by bremsstrahlung photons using a linear electron accelerator in the suitable energy range is a promising method for producing radioisotopes. The photonuclear production method is capable of making radioisotopes more conveniently, cheaply and with much less radioactive waste compared to existing methods. Historically, photo-nuclear reactions have not been exploited for isotope production because of the low specific activity that is generally associated with this production process, although the technique is well-known to be capable of producing large quantities of certain radioisotopes. We describe an optimization technique for a set of parameters to maximize specific activity of the final product. This set includes the electron beam energy and current, the end station design (an integrated converter and target as well as cooling system), the purity of materials used, and the activation time. These parameters are mutually dependent and thus their optimization is not trivial. 67Cu photonuclear production via 68Zn(γp)67Cu reaction was used as an example of such an optimization process.

  13. Anthropogenic radioisotopes to estimate rates of soil redistribution by wind

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Erosion of soil by wind and water is a degrading process that affects millions of hectares worldwide. Atmospheric testing of nuclear weapons and the resulting fallout of anthropogenic radioisotopes, particularly Cesium 137, has made possible the estimation of mean soil redistribution rates. The pe...

  14. Radioisotope production and management at Oak Ridge National Laboratory

    SciTech Connect

    Collins, E.D.; Aaron, W.S.; Alexander, C.W.; Bigelow, J.E.; Parks, J.T.; Tracy, J.G.; Wham, R.M.

    1994-09-01

    The production of radioisotopes has been one of the basic activities at Oak Ridge since the end of World War II. The importance of this work was best described by Alvin Weinberg, former Laboratory Director, when he wrote ``... If God has a golden book and writes down what it is that Oak Ridge National Laboratory did that had the biggest influence on science, I would guess that was the production and distribution of isotopes.`` Radioisotopes production continues to be an important aspect of Oak Ridge programs today and of those planned for the future. Past activities, current projects, and future plans and potentials will be described briefly in this paper. Also, some of the major issues facing the continued production of radioisotopes will be described. The scope of the program has always been primarily that of process development, followed by special batch-type productions, where no other supply exists. The technology developed has been available for adoption by US commercial corporations, and in cases where this has occurred, Oak Ridge has withdrawn as a supplier of the particular isotopes involved. One method of production that will not be described is that of target bombardment with an accelerator. This method was used at Oak Ridge prior to 1978 in the 86-inch Cyclotron. However, this method has not been used at Oak Ridge since then for radioisotope production, except as a research tool.

  15. Production capabilities in US nuclear reactors for medical radioisotopes

    SciTech Connect

    Mirzadeh, S.; Callahan, A.P.; Knapp, F.F. Jr. ); Schenter, R.E. )

    1992-11-01

    The availability of reactor-produced radioisotopes in the United States for use in medical research and nuclear medicine has traditionally depended on facilities which are an integral part of the US national laboratories and a few reactors at universities. One exception is the reactor in Sterling Forest, New York, originally operated as part of the Cintichem (Union Carbide) system, which is currently in the process of permanent shutdown. Since there are no industry-run reactors in the US, the national laboratories and universities thus play a critical role in providing reactor-produced radioisotopes for medical research and clinical use. The goal of this survey is to provide a comprehensive summary of these production capabilities. With the temporary shutdown of the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) in November 1986, the radioisotopes required for DOE-supported radionuclide generators were made available at the Brookhaven National Laboratory (BNL) High Flux Beam Reactor (HFBR). In March 1988, however, the HFBR was temporarily shut down which forced investigators to look at other reactors for production of the radioisotopes. During this period the Missouri University Research Reactor (MURR) played an important role in providing these services. The HFIR resumed routine operation in July 1990 at 85 MW power, and the HFBR resumed operation in June 1991, at 30 MW power. At the time of the HFBR shutdown, there was no available comprehensive overview which could provide information on status of the reactors operating in the US and their capabilities for radioisotope production. The obvious need for a useful overview was thus the impetus for preparing this survey, which would provide an up-to-date summary of those reactors available in the US at both the DOE-funded national laboratories and at US universities where service irradiations are currently or expected to be conducted.

  16. Operations of a Radioisotope-based Propulsion System Enabling CubeSat Exploration of the Outer Planets

    SciTech Connect

    Dr. Steven Howe; Nathan Jerred; Troy Howe; Adarsh Rajguru

    2014-05-01

    Exploration to the outer planets is an ongoing endeavor but in the current economical environment, cost reduction is the forefront of all concern. The success of small satellites such as CubeSats launched to Near-Earth Orbit has lead to examine their potential use to achieve cheaper science for deep space applications. However, to achieve lower cost missions; hardware, launch and operations costs must be minimized. Additionally, as we push towards smaller exploration beds with relative limited power sources, allowing for adequate communication back to Earth is imperative. Researchers at the Center for Space Nuclear Research are developing the potential of utilizing an advanced, radioisotope-based system. This system will be capable of providing both the propulsion power needed to reach the destination and the additional requirements needed to maintain communication while at location. Presented here are a basic trajectory analysis, communication link budget and concept of operations of a dual-mode (thermal and electric) radioisotope-based propulsion system, for a proposed mission to Enceladus (Saturnian icy moon) using a 6U CubeSat payload. The radioisotope system being proposed will be the integration of three sub-systems working together to achieve the overall mission. At the core of the system, stored thermal energy from radioisotope decay is transferred to a passing propellant to achieve high thrust – useful for quick orbital maneuvering. An auxiliary closed-loop Brayton cycle can be operated in parallel to the thrusting mode to provide short bursts of high power for high data-rate communications back to Earth. Additionally, a thermal photovoltaic (TPV) energy conversion system will use radiation heat losses from the core. This in turn can provide the electrical energy needed to utilize the efficiency of ion propulsion to achieve quick interplanetary transit times. The intelligent operation to handle all functions of this system under optimized conditions adds

  17. Monolithic CMUT on CMOS Integration for Intravascular Ultrasound Applications

    PubMed Central

    Zahorian, Jaime; Hochman, Michael; Xu, Toby; Satir, Sarp; Gurun, Gokce; Karaman, Mustafa; Degertekin, F. Levent

    2012-01-01

    One of the most important promises of capacitive micromachined ultrasonic transducer (CMUT) technology is integration with electronics. This approach is required to minimize the parasitic capacitances in the receive mode, especially in catheter based volumetric imaging arrays where the elements need to be small. Furthermore, optimization of the available silicon area and minimized number of connections occurs when the CMUTs are fabricated directly above the associated electronics. Here, we describe successful fabrication and performance evaluation of CMUT arrays for intravascular imaging on custom designed CMOS receiver electronics from a commercial IC foundry. The CMUT on CMOS process starts with surface isolation and mechanical planarization of the CMOS electronics to reduce topography. The rest of the CMUT fabrication is achieved by modifying a low temperature micromachining process through the addition of a single mask and developing a dry etching step to produce sloped sidewalls for simple and reliable CMUT to CMOS interconnection. This CMUT to CMOS interconnect method reduced the parasitic capacitance by a factor of 200 when compared with a standard wire bonding method. Characterization experiments indicate that the CMUT on CMOS elements are uniform in frequency response and are similar to CMUTs simultaneously fabricated on standard silicon wafers without electronics integration. Experiments on a 1.6 mm diameter dual-ring CMUT array with a 15 MHz center frequency show that both the CMUTs and the integrated CMOS electronics are fully functional. The SNR measurements indicate that the performance is adequate for imaging CTOs located 1 cm away from the CMUT array. PMID:23443701

  18. Role of Intravascular Ultrasound in Patients with Acute Myocardial Infarction

    PubMed Central

    Hong, Young Joon; Ahn, Youngkeun

    2015-01-01

    Rupture of a vulnerable plaque and subsequent thrombus formation are important mechanisms leading to the development of an acute myocardial infarction (AMI). Typical intravascular ultrasound (IVUS) features of AMI include plaque rupture, thrombus, positive remodeling, attenuated plaque, spotty calcification, and thin-cap fibroatheroma. No-reflow phenomenon was attributable to the embolization of thrombus and plaque debris that results from mechanical fragmentation of the vulnerable plaque by percutaneous coronary intervention (PCI). Several grayscale IVUS features including plaque rupture, thrombus, positive remodeling, greater plaque burden, decreased post-PCI plaque volume, and tissue prolapse, and virtual histology-IVUS features such as large necrotic corecontaining lesion and thin-cap fibroatheroma were the independent predictors of no-reflow phenomenon in AMI patients. Non-culprit lesions associated with recurrent events were more likely than those not associated with recurrent events to be characterized by a plaque burden of ≥70%, a minimal luminal area of ≤4.0 mm2, or to be classified as thin-cap fibroatheromas. PMID:26240578

  19. Quantitative recovery of pulmonary intravascular macrophages from sheep lungs.

    PubMed

    Rogers, R A; Tasat, D R; Warner, A E; Brain, J D

    1994-12-01

    Pulmonary intravascular macrophages (PIMs) adhere to the endothelium of lung capillaries and sequester circulating particles and pathogens from the blood. Iron oxide (gamma Fe2O3) 5 mg/kg, administered intravenously, specifically labeled PIMs in situ within the living sheep. Attempts to isolate gamma Fe2O3-labeled PIMs using vascular perfusion (VP) procedures yielded few cells. To improve recovery of PIMs, a proteolytic lung digestion (PLD) procedure was developed. Following PLD, gamma Fe2O3-containing PIMs were recovered by magnets and the amount of gamma Fe2O3 present measured by fluxgate magnetometry. Proteolytic lung digestion recovered 34% of the total gamma Fe2O3 in lung samples and yielded 2 x 10(5) PIMs/g lung with 95% viability. In contrast, VP recovered only 3% of the total gamma Fe2O3 in the lung; furthermore, less than 2% of the recovered gamma Fe2O3 was cell associated. Proteolytic lung digestion followed by magnetic separation is an effective way to recover viable sheep PIMs for in vitro study. PMID:7996045

  20. Microbial diversity on intravascular catheters from paediatric patients.

    PubMed

    Zhang, L; Marsh, N; Long, D; Wei, M; Morrison, M; Rickard, C M

    2015-12-01

    Microorganisms play important roles in intravascular catheter (IVC)-related infections, which are the most serious complications in children with IVCs, leading to increased hospitalisation, intensive care admissions, extensive antibiotic treatment and mortality. A greater understanding of bacterial communities is needed in order to improve the management of infections. We describe here the systematic culture-independent evaluation of IVC bacteriology in IVC biofilms. Twenty-four IVC samples (six peripherally inserted central catheters, eight central venous catheters and ten arterial catheters) were collected from 24 paediatric patients aged 0 to 14 years old. Barcoded amplicon libraries produced from genes coding 16S rRNA and roll-plate culture methods were used to determine the microbial composition of these samples. From a total of 1,043,406 high-quality sequence reads, eight microbial phyla and 136 diverse microbial genera were detected, separated into 12,224 operational taxonomic units (OTUs). Three phyla (Actinobacteria, Firmicutes and Proteobacteria) predominate the microorganism on the IVC surfaces, with Firmicutes representing nearly half of the OTUs found. Among the Firmicutes, Staphylococcus (15.0% of 16S rRNA reads), Streptococcus (9.6%) and Bacillus (6.1%) were the most common. Community composition did not appear to be affected by patients' age, gender, antibiotic treatment or IVC type. Differences in IVC microbiota were more likely associated with events arising from catheter dwell time, rather than the type of IVC used. PMID:26515578

  1. Impact of microbial attachment on intravascular catheter-related infections.

    PubMed

    Zhang, Li; Gowardman, John; Rickard, Claire M

    2011-07-01

    Intravascular catheters (IVCs) are the most frequently used medical devices in hospitals. However, they are associated with life-threatening IVC-related bloodstream infection (IVC-BSI), which is one of the main hospital-acquired infections, and continue to be associated with morbidity, mortality and additional medical cost. Most published studies focus on measuring the rate of IVC-BSIs and addressing their importance, but only a few studies have mentioned the possible routes for microbes entering the bloodstream, which would help in developing effective prevention methods, and large trial studies are lacking. Some studies on IVC-BSIs have reported the most frequently isolated microbes, but caution needs to be made since many fastidious microbes are not isolated under current laboratory conditions. Although it is known that microbes colonise IVC surfaces and develop biofilms, leading to IVC-BSI, the relationships of microbial biofilms with patients' symptoms or outcomes remain unclear. Here we discuss the knowledge gained from microbial research in other (non-IVC) medical and non-medical applications that may be helpful in understanding the IVC context. In addition, published theory and data regarding microbial colonisation and biofilm development specifically in IVCs are reviewed. More research is needed to explore mechanisms of IVC-BSI and to provide superior prevention strategies.

  2. Acoustic determination of early stages of intravascular blood coagulation.

    PubMed

    Uzlova, Svetlana G; Guria, Konstantin G; Guria, Georgy Th

    2008-10-13

    The blood coagulation system (BCS) is a complex biological system playing a principal role in the maintenance of haemostasis. Insufficient activity of the BCS may lead to bleeding and blood loss (e.g. in the case of haemophilia). On the other hand, excessive activity may cause intravascular blood coagulation, thromboses and embolization. Most of the methods currently used for BCS monitoring suffer from the major disadvantage of being invasive. The purpose of the present work is to demonstrate the feasibility of using ultrasonic methods for non-invasive registration of the early stages of blood coagulation processes in intensive flows. With this purpose, a special experimental set-up was designed, facilitating the simultaneous detection of optical and acoustic signals during the clotting process. It was shown that (i) as microemboli appear in the flow during the early stage of blood coagulation, the intensity of the Doppler signal increases twofold, and (ii) microemboli formation in the early stages of blood clotting always reveals itself through an acoustic contrast. Both of these effects are well defined, so we hope that they may be used for non-invasive BCS monitoring in clinical practice.

  3. Intravascular Ultrasound for Intracranial and Extracranial Carotid Artery Stent Placement

    PubMed Central

    Hussain, Ahmad S

    2016-01-01

    Intravascular ultrasound (IVUS) can provide valuable information regarding endoluminal morphology. We present the first description of IVUS-guided intracranial and extracranial carotid artery stent placement for arterial dissection. A 41-year-old female with a sudden-onset headache and blurred vision underwent a computed tomography (CT) angiogram imaging that revealed bilateral carotid artery dissections (BCAD) and a left vertebral artery dissection (VAD). Endovascular treatment (EVT) of a long segment right carotid artery dissection (CAD) was performed employing two Carotid WALLSTENT™ Monorails™ (8 x 36 mm, 10 x 31 mm) (Boston Scientific, Marlborough, MA). With the help of the IVUS, the distal stent was placed up to the petrous carotid artery, followed by the placement of the second stent in the immediate proximal location with some overlap that extended down to the carotid artery bulb. Intraoperative angiography and post-stenting IVUS revealed excellent stent placement with good resolution of the dissection and good luminal patency with pseudolumen obliteration. Stent use for intracranial circulation dissections will continue to be a favorable option given the decreased morbidity of endovascular therapy in this location. As endovascular surgeons become more facile with the use of IVUS, using it as a guide for stent placement and post-stenting confirmation will help them to ensure proper positioning and improved patency rates. PMID:27672529

  4. [Progress in diagnosis and treatment for disseminated intravascular coagulation].

    PubMed

    Wada, Hideo; Matsumoto, Takeshi; Aota, Takumi; Yamashita, Yoshiki

    2015-02-01

    As the development of a hypercoagulable state in the setting of disseminated intravascular coagulation (DIC) induces localized infection, therapy for DIC should be evaluated according to the findings of examinations for both severe sepsis and DIC. DIC is classified into the following types: "bleeding type," "organ failure type," "asymptomatic type," and "complication type." The "bleeding type" and "organ failure type" are considered to reflect the "plasmin inhibitor (PI) deficiency type" and "antithrombin (AT) deficiency type," respectively. In order to improve the diagnosis of DIC, in particular limitations in global coagulation tests, the Japanese Society of Thrombosis and Hemostasis recently proposed tentative diagnostic criteria for DIC using hemostatic molecular markers and AT. The recommendations for treatment of DIC, especially the use of AT concentrates, recombinant activated protein C and thrombomodulin, vary among several guidelines for the management of DIC. These agents inhibit the effects of key proteases in activating coagulation and consequently exert an anti-inflammatory effect on DIC. Hence, it is necessary to extensively evaluate these agents in well-conducted clinical trials.

  5. Back to the future: testing in disseminated intravascular coagulation.

    PubMed

    Toh, Cheng-Hock; Downey, Colin

    2005-11-01

    Following on from the first clinical observations on disseminated intravascular coagulation (DIC) in the nineteenth century, the dawn of laboratory testing for DIC began with the availability of assays that characterized the extrinsic and intrinsic pathways of coagulation. Markedly increased clotting times were the hallmark of DIC. As the understanding of the biochemistry of haemostasis and thrombosis improved, new tests were developed based on the molecular players that participate in the process. However, many are non-specific for DIC and/or are unwieldy in performance to keep apace with the demands of the acute clinical setting. The renewed emphasis in DIC for the modern laboratory of the twenty-first century has seen a return to the simple, rapid and practical global tests of coagulation within scoring systems that also capture the pathophysiological continuum by trend analysis. Additionally, new technologies based on these simple tests of coagulation hold promise in also indicating the in vivo interplay between coagulation and inflammation during DIC.

  6. Diagnostic criteria and laboratory tests for disseminated intravascular coagulation.

    PubMed

    Wada, Hideo; Matsumoto, Takeshi; Hatada, Tuyoshi

    2012-12-01

    Three diagnostic criteria for disseminated intravascular coagulation (DIC) have been established by the Japanese Ministry of Health, Labor and Welfare, the International Society on Thrombosis and Hemostasis (ISTH) and the Japanese Association for Acute Medicine. The diagnostic criteria involving global coagulation tests, such as the Japanese Ministry of Health, Labor and Welfare criteria and the ISTH overt diagnostic criteria, are first-generation DIC diagnostic criteria, those involving global coagulation tests and changes in these tests such as the Japanese Association for Acute Medicine criteria, are second-generation DIC diagnostic criteria, and those including non-overt DIC diagnostic criteria involving global coagulation tests, changes in these tests and hemostatic molecular markers will be the future (third-generation) DIC diagnostic criteria. There are no significant differences in the three diagnostic criteria with respect to predicting poor outcomes. Therefore, the third generation of diagnostic criteria including hemostatic molecular markers is expected to be established. Standardization and the determination of adequate cutoff values should be required for each laboratory test.

  7. Optimization of intravascular brachytherapy treatment planning in peripheral arteries.

    PubMed

    Zhou, Zhengdong; Haigron, Pascal; Shu, Huazhong; Yu, Wenxue; Moisan, Cécile; Manens, Jean-Pierre; Lucas, Antoine; Luo, Limin

    2007-09-01

    This work deals with the treatment planning optimization for intravascular brachytherapy (IVB) in peripheral arteries. The objective is both to quantitatively study the validity of different hypotheses required for a reliable application of the treatment with current techniques, and to contribute to the definition and the specification of a new optimized procedure taking into account the actual patient's vessel geometry. The detection of vascular luminal surface was performed by an image analysis process, i.e., virtual active navigation, applied to standard CT data. Dose distribution was calculated according to the formalism proposed and recommended by the AAPM in TG43 and TG60. A method combining simulated annealing and BFGS algorithms was applied to optimize the parameters associated with the dwell points such as their number, positions, and dwell times. Dose-surface histogram (DSH) was used to evaluate the dose distribution results. Four levels of accuracy in target surface description were tested. The application of this optimization method to four different CT data sets including patient data, phantom and animal models showed that the treatment plan can be improved when the actual vessel geometry has been taken into account.

  8. Light intensity matching between different intravascular optical coherence tomography systems

    NASA Astrophysics Data System (ADS)

    Liu, Shengnan; Eggermont, Jeroen; Nakatani, Shimpei; Lelieveldt, Boudewijn P. F.; Dijkstra, Jouke

    2016-02-01

    Currently two commercial intravascular optical coherence tomography (IVOCT) systems are available: Illumien Optis from St. Jude Medical (SJM) and Lunawave from Terumo. Both systems store the light intensity data in a raw vendor specific polar format. However, whereas SJM uses 16-bits per pixel Terumo uses 8-bits meaning the intensity values are in different ranges. This complicates quantitative light intensity based analysis when comparing results based on data from both systems. Therefore, this work aims to find an intensity transformation function from Terumo's 8-bit OFDI data to SJM's 16-bit range. The data consists of 8 pullbacks, 4 acquired with each system in the same arteries of 2 different patents pre- and post-stenting implantation. A total of 133 matching sections without stent struts from the two sets of pullbacks were identified based on landmarks such as side-branches and calcified regions. Since the main region of interest in the image is the tissue region only the pixels within 2mm behind the lumen border are used. In order to match the SJM data range, the Terumo data was rescaled and cumulative distribution functions (CDF) were calculated based on the histogram distributions. Comparing these CDFs, the transformation function can be determined. Application of this transformation function not only improves the visual similarity of matching slices it can also be used for further quantitative analysis.

  9. Disseminated intravascular coagulopathy: manifestations after a routine dental extraction.

    PubMed

    Peters, Kelly A; Triolo, Peter T; Darden, Daryle L

    2005-04-01

    Clinical signs and symptoms of acute disseminated intravascular coagulopathy (DIC) include bleeding from body orifices, such as the nose, mouth, or ear, bleeding from an intravenous (IV) site, areas of ecchymosis, or blood in the urine or stool. The underlying disease triggering DIC usually determines the clinical presentation. However, patients with chronic DIC (compensated DIC) may possess subclinical signs and symptoms, and the bleeding disorder may only be identified through laboratory findings. In this compensated form, the triggering factor is exposed slowly and in small amounts (seen in malignancies and vasculitis), allowing replenishing of the augmented factors by the liver, adequate reticuloendothelial clearance of fibrin degradation products, and increased production of platelets, which prevent secondary fibrinolysis and the signs of bleeding. 1,4 We report a case of an 82-year-old male who presented to the emergency room 24 hours after a routine dental extraction with bleeding from the tooth socket, severe hypotension, and presence of ecchymosis on his chest. Clinical and radiographic exam revealed multiple thoracic and abdominal aortic aneurysms, as well as infrarenal and iliac aneurysms, continuous oral hemorrhage, and a unique presentation rarely documented in the literature: a bleeding tooth socket as the initial clinical sign and presentation of DIC.

  10. Low-artifact intravascular devices: MR imaging evaluation.

    PubMed

    Teitelbaum, G P; Ortega, H V; Vinitski, S; Stern, H; Tsuruda, J S; Mitchell, D G; Rifkin, M D; Bradley, W G

    1988-09-01

    Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. PMID:3406402

  11. Intravascular Ultrasound for Intracranial and Extracranial Carotid Artery Stent Placement

    PubMed Central

    Hussain, Ahmad S

    2016-01-01

    Intravascular ultrasound (IVUS) can provide valuable information regarding endoluminal morphology. We present the first description of IVUS-guided intracranial and extracranial carotid artery stent placement for arterial dissection. A 41-year-old female with a sudden-onset headache and blurred vision underwent a computed tomography (CT) angiogram imaging that revealed bilateral carotid artery dissections (BCAD) and a left vertebral artery dissection (VAD). Endovascular treatment (EVT) of a long segment right carotid artery dissection (CAD) was performed employing two Carotid WALLSTENT™ Monorails™ (8 x 36 mm, 10 x 31 mm) (Boston Scientific, Marlborough, MA). With the help of the IVUS, the distal stent was placed up to the petrous carotid artery, followed by the placement of the second stent in the immediate proximal location with some overlap that extended down to the carotid artery bulb. Intraoperative angiography and post-stenting IVUS revealed excellent stent placement with good resolution of the dissection and good luminal patency with pseudolumen obliteration. Stent use for intracranial circulation dissections will continue to be a favorable option given the decreased morbidity of endovascular therapy in this location. As endovascular surgeons become more facile with the use of IVUS, using it as a guide for stent placement and post-stenting confirmation will help them to ensure proper positioning and improved patency rates.

  12. Intravascular Ultrasound for Intracranial and Extracranial Carotid Artery Stent Placement.

    PubMed

    Hussain, Ahmad S; Hussain, Namath S

    2016-01-01

    Intravascular ultrasound (IVUS) can provide valuable information regarding endoluminal morphology. We present the first description of IVUS-guided intracranial and extracranial carotid artery stent placement for arterial dissection. A 41-year-old female with a sudden-onset headache and blurred vision underwent a computed tomography (CT) angiogram imaging that revealed bilateral carotid artery dissections (BCAD) and a left vertebral artery dissection (VAD). Endovascular treatment (EVT) of a long segment right carotid artery dissection (CAD) was performed employing two Carotid WALLSTENT™ Monorails™ (8 x 36 mm, 10 x 31 mm) (Boston Scientific, Marlborough, MA). With the help of the IVUS, the distal stent was placed up to the petrous carotid artery, followed by the placement of the second stent in the immediate proximal location with some overlap that extended down to the carotid artery bulb. Intraoperative angiography and post-stenting IVUS revealed excellent stent placement with good resolution of the dissection and good luminal patency with pseudolumen obliteration. Stent use for intracranial circulation dissections will continue to be a favorable option given the decreased morbidity of endovascular therapy in this location. As endovascular surgeons become more facile with the use of IVUS, using it as a guide for stent placement and post-stenting confirmation will help them to ensure proper positioning and improved patency rates. PMID:27672529

  13. Effect of intravascular cellular aggregate dissolution in postoperative patients.

    PubMed Central

    Dawidson, I; Barrett, J; Miller, E; Litwin, M S

    1975-01-01

    It was the purpose of this study to confirm whether the increase in packed cell (PC) viscosity that occurs in humans after elective surgery is accompanied by a decrease in total body O2 consumption as previously noted in animals, and further to define the effect of resolution of intravascular cellular aggregates (ICA) on these parameters. Thirty nine patients were studied. Total body O2 consumption was 76% of normal 6 hours postop, 81% of normal 24 hours postop and 87% of normal 48 hours postop. Twenty four hours after operation PC viscosity and increased markedly. Saline infusion had no significant effect on total body O2 consumption or PC viscosity, either pre- or postop, but WB viscosity decreased linearly in proportion in the drop in hematocrit. Resolution of ICA by dextran-40 infusion was associated with return of total body O2 consumption and PC viscosity to normal; a decrease in WB viscosity was disproportionately greater than would have been seen had the decrease been due solely to the drop in hematocrit. It is concluded that in humans surgical trauma causes an increase in PC viscosity and microcirculatory impairment as evidenced by a decrease in total body O2 consumption. Resolution of ICA by dextran-40 infusion reverses that detrimental changes. PMID:1190882

  14. Heartbeat OCT: in vivo intravascular megahertz-optical coherence tomography

    PubMed Central

    Wang, Tianshi; Pfeiffer, Tom; Regar, Evelyn; Wieser, Wolfgang; van Beusekom, Heleen; Lancee, Charles T.; Springeling, Geert; Krabbendam, Ilona; van der Steen, Antonius F.W.; Huber, Robert; van Soest, Gijs

    2015-01-01

    Cardiac motion artifacts, non-uniform rotational distortion and undersampling affect the image quality and the diagnostic impact of intravascular optical coherence tomography (IV-OCT). In this study we demonstrate how these limitations of IV-OCT can be addressed by using an imaging system that we called “Heartbeat OCT”, combining a fast Fourier Domain Mode Locked laser, fast pullback, and a micromotor actuated catheter, designed to examine a coronary vessel in less than one cardiac cycle. We acquired in vivo data sets of two coronary arteries in a porcine heart with both Heartbeat OCT, working at 2.88 MHz A-line rate, 4000 frames/s and 100 mm/s pullback speed, and with a commercial system. The in vivo results show that Heartbeat OCT provides faithfully rendered, motion-artifact free, fully sampled vessel wall architecture, unlike the conventional IV-OCT data. We present the Heartbeat OCT system in full technical detail and discuss the steps needed for clinical translation of the technology. PMID:26713214

  15. Reactor production and processing of radioisotopes for therapeutic applications in nuclear medicine

    SciTech Connect

    Knapp, F.F. Jr.; Mirzadeh, S.; Beets, A.L.

    1995-02-01

    Nuclear reactors continue to play an important role in providing radioisotopes for nuclear medicine. Many reactor-produced radioisotopes are ``neutron rich`` and decay by beta-emission and are thus of interest for therapeutic applications. This talk discusses the production and processing of a variety of reactor-produced radioisotopes of current interest, including those produced by the single neutron capture process, double neutron capture and those available from beta-decay of reactorproduced radioisotopes. Generators prepared from reactorproduced radioisotopes are of particular interest since repeated elution inexpensively provides many patient doses. The development of the alumina-based W-188/Re-188 generator system is discussed in detail.

  16. Handheld CZT radiation detector

    DOEpatents

    Murray, William S.; Butterfield, Kenneth B.; Baird, William

    2004-08-24

    A handheld CZT radiation detector having a CZT gamma-ray sensor, a multichannel analyzer, a fuzzy-logic component, and a display component is disclosed. The CZT gamma-ray sensor may be a coplanar grid CZT gamma-ray sensor, which provides high-quality gamma-ray analysis at a wide range of operating temperatures. The multichannel analyzer categorizes pulses produce by the CZT gamma-ray sensor into channels (discrete energy levels), resulting in pulse height data. The fuzzy-logic component analyzes the pulse height data and produces a ranked listing of radioisotopes. The fuzzy-logic component is flexible and well-suited to in-field analysis of radioisotopes. The display component may be a personal data assistant, which provides a user-friendly method of interacting with the detector. In addition, the radiation detector may be equipped with a neutron sensor to provide an enhanced mechanism of sensing radioactive materials.

  17. SNAP 19 Viking RTG flight configuration and integration testing. [Radioisotope Thermoelectric Generator

    NASA Technical Reports Server (NTRS)

    Brittain, W. M.; Christenbury, S. T.

    1974-01-01

    The Viking-75 mission environments and lander interface requirements which influence the design of the RTG (radioisotope thermoelectric generator), as well as RTG-related constraints are discussed. The baseline RTG design evolved from these considerations is presented with particular emphasis on the design features which make the Viking RTG unique. These features include a gas management system employing a separate gas reservoir to maintain the RTG hot junction and heat source temperatures within a desired range throughout the various mission phases, as well as a specially profiled housing/radiator assembly which facilitates both ground cooling of the RTGs prior to launch and thermal control of the lander after landing. Also presented is the expected RTG electrical performance when subjected to the various mission environments/requirements, such as 'power-up' operations in Mars orbit just prior to the entry, and thermal cycling on the Martian surface after landing.

  18. Determination of Radioisotope Content by Measurement of Waste Package Dose Rates - 13394

    SciTech Connect

    Souza, Daiane Cristini B.; Gimenes Tessaro, Ana Paula; Vicente, Roberto

    2013-07-01

    The objective of this communication is to report the observed correlation between the calculated air kerma rates produced by radioactive waste drums containing untreated ion-exchange resin and activated charcoal slurries with the measured radiation field of each package. Air kerma rates at different distances from the drum surface were calculated with the activity concentrations previously determined by gamma spectrometry of waste samples and the estimated mass, volume and geometry of solid and liquid phases of each waste package. The water content of each waste drum varies widely between different packages. Results will allow determining the total activity of wastes and are intended to complete the previous steps taken to characterize the radioisotope content of wastes packages. (authors)

  19. Radioimmunotherapy: A Specific Treatment Protocol for Cancer by Cytotoxic Radioisotopes Conjugated to Antibodies

    PubMed Central

    Kawashima, Hidekazu

    2014-01-01

    Radioimmunotherapy (RIT) represents a selective internal radiation therapy, that is, the use of radionuclides conjugated to tumor-directed monoclonal antibodies (including those fragments) or peptides. In a clinical field, two successful examples of this treatment protocol are currently extended by 90Y-ibritumomab tiuxetan (Zevalin) and 131I-tositumomab (Bexxar), both of which are anti-CD20 monoclonal antibodies coupled to cytotoxic radioisotopes and are approved for the treatment of non-Hodgkin lymphoma patients. In addition, some beneficial observations are obtained in preclinical studies targeting solid tumors. To date, in order to reduce the unnecessary exposure and to enhance the therapeutic efficacy, various biological, chemical, and treatment procedural improvements have been investigated in RIT. This review outlines the fundamentals of RIT and current knowledge of the preclinical/clinical trials for cancer treatment. PMID:25379535

  20. Radioimmunotherapy: a specific treatment protocol for cancer by cytotoxic radioisotopes conjugated to antibodies.

    PubMed

    Kawashima, Hidekazu

    2014-01-01

    Radioimmunotherapy (RIT) represents a selective internal radiation therapy, that is, the use of radionuclides conjugated to tumor-directed monoclonal antibodies (including those fragments) or peptides. In a clinical field, two successful examples of this treatment protocol are currently extended by (90)Y-ibritumomab tiuxetan (Zevalin) and (131)I-tositumomab (Bexxar), both of which are anti-CD20 monoclonal antibodies coupled to cytotoxic radioisotopes and are approved for the treatment of non-Hodgkin lymphoma patients. In addition, some beneficial observations are obtained in preclinical studies targeting solid tumors. To date, in order to reduce the unnecessary exposure and to enhance the therapeutic efficacy, various biological, chemical, and treatment procedural improvements have been investigated in RIT. This review outlines the fundamentals of RIT and current knowledge of the preclinical/clinical trials for cancer treatment.

  1. The Natural Radiation Environment, Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Kastner, Jacob

    The somatic and genetic effects of naturally occurring radiation are described in this illustrated booklet. Internal sources of radiation from food, water, and air and external sources including radioisotopes in rock, brick, water, and air and cosmic radiation are tabulated. Detection methods are described, and their use in biological and physical…

  2. HHV-8 and EBV-positive intravascular lymphoma: an unusual presentation of extracavitary primary effusion lymphoma

    PubMed Central

    Crane, Genevieve M.; Ambinder, Richard F.; Shirley, Courtney M.; Fishman, Elliot K.; Kasamon, Yvette L.; Taube, Janis M.; Borowitz, Michael J.; Duffield, Amy S.

    2014-01-01

    Intravascular lymphomas are rare and aggressive hematolymphoid tumors. Here we describe a human herpesvirus type-8/Kaposi sarcoma-associated herpesvirus (HHV-8/KSHV) and Epstein-Barr virus (EBV) positive intravascular lymphoma. The patient was a 59 year-old HIV-positive man who presented with diarrhea, abdominal pain, fevers, night sweats, and weight loss. Radiographic studies of the abdomen and pelvis revealed numerous subcentimeter nodules within the subcutaneous fat that lacked connection to the skin. An excisional biopsy demonstrated large atypical cells within vessels in the deep subcutaneous fat, and many of the vessels contained extensive organizing thrombi. The atypical cells lacked strong expression of most B-cell markers but were positive for MUM-1 and showed partial expression of several T-cell markers. An immunohistochemical stain for HHV-8 and an in situ hybridization for EBV were both positive in the neoplastic cells. The disease had a rapidly progressive and fatal course. This lymphoma appears to represent an entirely intravascular form of primary effusion lymphoma, and highlights the propensity for HHV-8 and EBV-positive lymphoid neoplasms to show aberrant expression of T-cell markers, illustrates the utility of skin biopsies for the diagnosis of intravascular lymphoma, and suggests that biopsies to evaluate for intravascular lymphoma should be relatively deep and include subcutaneous fat. PMID:24525514

  3. Percutaneous Retrieval of Misplaced Intravascular Foreign Objects with the Dormia Basket: An Effective Solution

    SciTech Connect

    Sheth, Rahul Someshwar, Vimal; Warawdekar, Gireesh

    2007-02-15

    Purpose. We report our experience of the retrieval of intravascular foreign body objects by the percutaneous use of the Gemini Dormia basket. Methods. Over a period of 2 years we attempted the percutaneous removal of intravascular foreign bodies in 26 patients. Twenty-six foreign bodies were removed: 8 intravascular stents, 4 embolization coils, 9 guidewires, 1 pacemaker lead, and 4 catheter fragments. The percutaneous retrieval was achieved with a combination of guide catheters and the Gemini Dormia basket. Results. Percutaneous retrieval was successful in 25 of 26 patients (96.2%). It was possible to remove all the intravascular foreign bodies with a combination of guide catheters and the Dormia basket. No complication occurred during the procedure, and no long-term complications were registered during the follow-up period, which ranged from 6 months to 32 months (mean 22.4 months overall). Conclusion. Percutaneous retrieval is an effective and safe technique that should be the first choice for removal of an intravascular foreign body.

  4. Imminent Cardiac Risk Assessment via Optical Intravascular Biochemical Analysis

    SciTech Connect

    Wetzel, D.; Wetzel, L; Wetzel, M; Lodder, R

    2009-01-01

    Heart disease is by far the biggest killer in the United States, and type II diabetes, which affects 8% of the U.S. population, is on the rise. In many cases, the acute coronary syndrome and/or sudden cardiac death occurs without warning. Atherosclerosis has known behavioral, genetic and dietary risk factors. However, our laboratory studies with animal models and human post-mortem tissue using FT-IR microspectroscopy reveal the chemical microstructure within arteries and in the arterial walls themselves. These include spectra obtained from the aortas of ApoE-/- knockout mice on sucrose and normal diets showing lipid deposition in the former case. Also pre-aneurysm chemical images of knockout mouse aorta walls, and spectra of plaque excised from a living human patient are shown for comparison. In keeping with the theme of the SPEC 2008 conference Spectroscopic Diagnosis of Disease this paper describes the background and potential value of a new catheter-based system to provide in vivo biochemical analysis of plaque in human coronary arteries. We report the following: (1) results of FT-IR microspectroscopy on animal models of vascular disease to illustrate the localized chemical distinctions between pathological and normal tissue, (2) current diagnostic techniques used for risk assessment of patients with potential unstable coronary syndromes, and (3) the advantages and limitations of each of these techniques illustrated with patent care histories, related in the first person, by the physician coauthors. Note that the physician comments clarify the contribution of each diagnostic technique to imminent cardiac risk assessment in a clinical setting, leading to the appreciation of what localized intravascular chemical analysis can contribute as an add-on diagnostic tool. The quality of medical imaging has improved dramatically since the turn of the century. Among clinical non-invasive diagnostic tools, laboratory tests of body fluids, EKG, and physical examination are

  5. [Relationship between the state of intravascular bubbles and microcirculation system].

    PubMed

    Yuan, J; Pan, L; Wang, Q; Ji, Z; Gao, J

    1996-08-01

    To confirm the hypothesis that air bubbles were unable to block the blood vessels and that the state of the intravascular bubbles was determined by the function of the circulatory system, 35 guinea pigs were pressurized then were decompressed to normal pressure. Microscopic observation was made of the bulbar conjunctival, dorsum auricular and subcutaneous vessels in 33 surviving animals. Air bubbles of different amounts, sizes and shapes were found in the dorsum auricular and subcutaneous vein of all the amimals and in the bulbar conjunctival oriridal artery of 16 animals, and in some cases the vessels were even filled with bubbles. The bubbles ran in the same direction and at the same speed as the blood flow. They could run in a backward, to-and-fro or sluggish flow. The bubbles looked shapeless and tended to break and divided into branch flows where the vessel branches. The bubbles were motionless at the proximal end of the artery occluded due to spasm or when the blood was stagnated. Under the action of the blood pressure the bubbles could expand the vessel and push forward. The bubbles showed a tendency of flowing with ease with the function of the vessel recovered. The results suggest that bubbles of any size in the vessel could easily change their shape under the action of the blood flow and pressure, and pass through vessels of any diameter and circulate with the blood. Only when a vessel was occluded due to spasm or the blood in a vessel was stagnated could the bubbles be motionless, but it was not that the bubbles blocked the vessel.

  6. Protection against high intravascular pressure in giraffe legs.

    PubMed

    Petersen, Karin K; Hørlyck, Arne; Ostergaard, Kristine H; Andresen, Joergen; Broegger, Torbjoern; Skovgaard, Nini; Telinius, Niklas; Laher, Ismael; Bertelsen, Mads F; Grøndahl, Carsten; Smerup, Morten; Secher, Niels H; Brøndum, Emil; Hasenkam, John M; Wang, Tobias; Baandrup, Ulrik; Aalkjaer, Christian

    2013-11-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along the artery. Histology of the isolated median artery confirmed dense sympathetic innervation at the narrowing. Structure and contractility of small arteries from muscular beds in the leg and neck were compared. The arteries from the legs demonstrated an increased media thickness-to-lumen diameter ratio, increased media volume, and increased numbers of smooth muscle cells per segment length and furthermore, they contracted more strongly than arteries from the neck (500 ± 49 vs. 318 ± 43 mmHg; n = 6 legs and neck, respectively). Finally, the transient increase in interstitial fluid pressure following injection of saline was 5.5 ± 1.7 times larger (n = 8) in the leg than in the neck. We conclude that 1) tissue compliance in the legs is low; 2) large arteries of the legs function as resistance arteries; and 3) structural adaptation of small muscle arteries allows them to develop an extraordinary tension. All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure.

  7. Mechanotransductional basis of endothelial cell response to intravascular bubbles.

    PubMed

    Klinger, Alexandra L; Pichette, Benjamin; Sobolewski, Peter; Eckmann, David M

    2011-10-01

    Vascular air embolism resulting from too rapid decompression is a well-known risk in deep-sea diving, aviation and space travel. It is also a common complication during surgery or other medical procedures when air or other endogenously administered gas is entrained in the circulation. Preventive and post-event treatment options are extremely limited for this dangerous condition, and none of them address the poorly understood pathophysiology of endothelial response to intravascular bubble presence. Using a novel apparatus allowing precise manipulation of microbubbles in real time fluorescence microscopy studies, we directly measure human umbilical vein endothelial cell responses to bubble contact. Strong intracellular calcium transients requiring extracellular calcium are observed upon cell-bubble interaction. The transient is eliminated both by the presence of the stretch activated channel inhibitor, gadolinium, and the transient receptor potential vanilliod family inhibitor, ruthenium red. No bubble induced calcium upsurge occurs if the cells are pretreated with an inhibitor of actin polymerization, cytochalasin-D. This study explores the biomechanical mechanisms at play in bubble interfacial interactions with endothelial surface layer (ESL) macromolecules, reassessing cell response after selective digestion of glycocalyx glycosoaminoglycans, hyaluran (HA) and heparin sulfate (HS). HA digestion causes reduction of cell-bubble adherence and a more rapid induction of calcium influx after contact. HS depletion significantly decreases calcium transient amplitudes, as does pharmacologically induced sydencan ectodomain shedding. The surfactant perfluorocarbon Oxycyte abolishes any bubble induced calcium transient, presumably through direct competition with ESL macromolecules for interfacial occupancy, thus attenuating the interactions that trigger potentially deleterious biochemical pathways.

  8. Supportive management strategies for disseminated intravascular coagulation. An international consensus.

    PubMed

    Squizzato, Alessandro; Hunt, Beverley J; Kinasewitz, Gary T; Wada, Hideo; Ten Cate, Hugo; Thachil, Jecko; Levi, Marcel; Vicente, Vicente; D'Angelo, Armando; Di Nisio, Marcello

    2016-05-01

    The cornerstone of the management of disseminated intravascular coagulation (DIC) is the treatment of the underlying condition triggering the coagulopathy. However, a number of uncertainties remain over the optimal supportive treatment. The aim of this study was to provide evidence and expert-based recommendations on the optimal supportive haemostatic and antithrombotic treatment strategies for patients with DIC. A working group defined five relevant clinical scenarios. Published studies were systematically searched in the MEDLINE and EMBASE databases (up to May 2014). Seven internationally recognised experts were asked to independently provide clinical advice. A two-phase blinded data collection technique was used to reach consensus. Only three randomised controlled trials (RCTs) on the supportive management of DIC were identified. The RCTs (overall less than 100 patients) investigated the use of fresh frozen plasma and platelet transfusion and found no differences in survival between the intervention and control groups. The experts' approach was heterogeneous, although there was consensus that supportive management should vary according to the underlying cause, clinical manifestations and severity of blood test abnormalities. Platelet transfusion should be given to maintain platelet count > 50×10⁹/l in case of bleeding while a lower threshold of 20 to 30×10⁹/l may be used in DIC without bleeding. Thromboprophylaxis with low-molecular-weight heparin is advised until bleeding ensues or platelet count drops below 30×10⁹/l. In conclusion, in the absence of solid evidence from RCTs, an individualised supportive management of DIC is advisable based on the type of underlying disease, presence of bleeding or thrombotic complications and laboratory tests results.

  9. Thromboelastometry in patients with severe sepsis and disseminated intravascular coagulation.

    PubMed

    Sivula, Mirka; Pettilä, Ville; Niemi, Tomi T; Varpula, Marjut; Kuitunen, Anne H

    2009-09-01

    Severe sepsis induces coagulopathy, which may lead to disseminated intravascular coagulation (DIC). Thromboelastometry is a point-of-care whole blood coagulation monitor, which has been validated in human endotoxemia model. We assessed thromboelastometry in severe sepsis and overt DIC and investigated its applicability in differentiating sepsis-related coagulation disturbances. Thromboelastometry (EXTEM and FIBTEM tests) and traditional coagulation assays were analyzed in 28 patients with severe sepsis, 12 of who fulfilled the criteria of overt DIC on admission. Ten healthy persons served as controls. Coagulation parameters, clotting time, clot formation time (CFT), alpha angle, maximal clot firmness (MCF) and lysis index at 60 min, were registered. In patients with overt DIC, EXTEM MCF, CFT and alpha angle differed from that in both healthy controls and patients without DIC, indicating hypocoagulation (MCF 52, 63 and 68 mm; CFT 184, 88 and 73 s; and alpha angle 58, 72 and 76 degrees , respectively, P < 0.01 for all). In patients without DIC, the trend was toward hypercoagulation in EXTEM and FIBTEM MCF (68 vs. 63 mm, P = 0.042 and 23 vs. 15 mm, P = 0.034, respectively). Receiver operating characteristic curves showed that MCF, CFT and alpha angle discriminated patients with overt DIC moderately (area under curve 0.891, 0.815 and 0.828, respectively, P < 0.001 for all). Traditional coagulation assays showed progressively worsening coagulopathy from controls to septic patients without DIC and further to those with overt DIC. We conclude that thromboelastometry may be a valuable tool in assessing whole blood coagulation capacity in patients with severe sepsis with and without overt DIC.

  10. Protection against high intravascular pressure in giraffe legs.

    PubMed

    Petersen, Karin K; Hørlyck, Arne; Ostergaard, Kristine H; Andresen, Joergen; Broegger, Torbjoern; Skovgaard, Nini; Telinius, Niklas; Laher, Ismael; Bertelsen, Mads F; Grøndahl, Carsten; Smerup, Morten; Secher, Niels H; Brøndum, Emil; Hasenkam, John M; Wang, Tobias; Baandrup, Ulrik; Aalkjaer, Christian

    2013-11-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along the artery. Histology of the isolated median artery confirmed dense sympathetic innervation at the narrowing. Structure and contractility of small arteries from muscular beds in the leg and neck were compared. The arteries from the legs demonstrated an increased media thickness-to-lumen diameter ratio, increased media volume, and increased numbers of smooth muscle cells per segment length and furthermore, they contracted more strongly than arteries from the neck (500 ± 49 vs. 318 ± 43 mmHg; n = 6 legs and neck, respectively). Finally, the transient increase in interstitial fluid pressure following injection of saline was 5.5 ± 1.7 times larger (n = 8) in the leg than in the neck. We conclude that 1) tissue compliance in the legs is low; 2) large arteries of the legs function as resistance arteries; and 3) structural adaptation of small muscle arteries allows them to develop an extraordinary tension. All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure. PMID:24005251

  11. Environmental assessment for radioisotope heat source fuel processing and fabrication

    SciTech Connect

    Not Available

    1991-07-01

    DOE has prepared an Environmental Assessment (EA) for radioisotope heat source fuel processing and fabrication involving existing facilities at the Savannah River Site (SRS) near Aiken, South Carolina and the Los Alamos National Laboratory (LANL) near Los Alamos, New Mexico. The proposed action is needed to provide Radioisotope Thermoelectric Generators (RTG) to support the National Aeronautics and Space Administration's (NASA) CRAF and Cassini Missions. Based on the analysis in the EA, DOE has determined that the proposed action does not constitute a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, an Environmental Impact Statement is not required. 30 refs., 5 figs.

  12. Process for radioisotope recovery and system for implementing same

    DOEpatents

    Meikrantz, David H.; Todd, Terry A.; Tranter, Troy J.; Horwitz, E. Philip

    2009-10-06

    A method of recovering daughter isotopes from a radioisotope mixture. The method comprises providing a radioisotope mixture solution comprising at least one parent isotope. The at least one parent isotope is extracted into an organic phase, which comprises an extractant and a solvent. The organic phase is substantially continuously contacted with an aqueous phase to extract at least one daughter isotope into the aqueous phase. The aqueous phase is separated from the organic phase, such as by using an annular centrifugal contactor. The at least one daughter isotope is purified from the aqueous phase, such as by ion exchange chromatography or extraction chromatography. The at least one daughter isotope may include actinium-225, radium-225, bismuth-213, or mixtures thereof. A liquid-liquid extraction system for recovering at least one daughter isotope from a source material is also disclosed.

  13. Process for radioisotope recovery and system for implementing same

    DOEpatents

    Meikrantz, David H.; Todd, Terry A.; Tranter, Troy J.; Horwitz, E. Philip

    2007-01-02

    A method of recovering daughter isotopes from a radioisotope mixture. The method comprises providing a radioisotope mixture solution comprising at least one parent isotope. The at least one parent isotope is extracted into an organic phase, which comprises an extractant and a solvent. The organic phase is substantially continuously contacted with an aqueous phase to extract at least one daughter isotope into the aqueous phase. The aqueous phase is separated from the organic phase, such as by using an annular centrifugal contactor. The at least one daughter isotope is purified from the aqueous phase, such as by ion exchange chromatography or extraction chromatography. The at least one daughter isotope may include actinium-225, radium-225, bismuth-213, or mixtures thereof. A liquid-liquid extraction system for recovering at least one daughter isotope from a source material is also disclosed.

  14. Investigation of Insulation Materials for Future Radioisotope Power Systems

    NASA Technical Reports Server (NTRS)

    Cornell, Peggy A.; Hurwitz, Frances I.; Ellis, David L.; Schmitz, Paul C.

    2013-01-01

    NASA's Radioisotope Power Systems (RPS) Technology Advancement Project is developing next generation high-temperature insulation materials that directly benefit thermal management and improve performance of RPS for future science missions. Preliminary studies on the use of multilayer insulation (MLI) for Stirling convertors used on the Advanced Stirling Radioisotope Generator (ASRG) have shown the potential benefits of MLI for space vacuum applications in reducing generator size and increasing specific power (W/kg) as compared to the baseline Microtherm HT (Microtherm, Inc.) insulation. Further studies are currently being conducted at NASA Glenn Research Center on candidate MLI foils and aerogel composite spacers. This paper presents the method of testing of foils and spacers and experimental results to date.

  15. Investigation of Insulation Materials for Future Radioisotope Power Systems (RPS)

    NASA Technical Reports Server (NTRS)

    Cornell, Peggy A.; Hurwitz, Frances I.; Ellis, David L.; Schmitz, Paul C.

    2013-01-01

    NASA's Radioisotope Power System (RPS) Technology Advancement Project is developing next generation high temperature insulation materials that directly benefit thermal management and improve performance of RPS for future science missions. Preliminary studies on the use of multilayer insulation (MLI) for Stirling convertors used on the Advanced Stirling Radioisotope Generator (ASRG) have shown the potential benefits of MLI for space vacuum applications in reducing generator size and increasing specific power (W/kg) as compared to the baseline Microtherm HT (Microtherm, Inc.) insulation. Further studies are currently being conducted at NASA Glenn Research Center (GRC) on candidate MLI foils and aerogel composite spacers. This paper presents the method of testing of foils and spacers and experimental results to date.

  16. Metal matrix composite fuel for space radioisotope energy sources

    NASA Astrophysics Data System (ADS)

    Williams, H. R.; Ning, H.; Reece, M. J.; Ambrosi, R. M.; Bannister, N. P.; Stephenson, K.

    2013-02-01

    Radioisotope fuels produce heat that can be used for spacecraft thermal control or converted to electricity. They must retain integrity in the event of destruction or atmospheric entry of the parent spacecraft. Addition of a metal matrix to the actinide oxide could yield a more robust fuel form. Neodymium (III) oxide (Nd2O3) - niobium metal matrix composites were produced using Spark Plasma Sintering; Nd2O3 is a non-radioactive surrogate for americium (III) oxide (Am2O3). Two compositions, 70 and 50 wt% Nd2O3, were mechanically tested under equibiaxial (ring-on-ring) flexure according to ASTM C1499. The addition of the niobium matrix increased the mean flexural strength by a factor of about 2 compared to typical ceramic nuclear fuels, and significantly increased the Weibull modulus to over 20. These improved mechanical properties could result in reduced fuel dispersion in severe accidents and improved safety of space radioisotope power systems.

  17. Safety status of space radioisotope and reactor power sources

    NASA Technical Reports Server (NTRS)

    Bennett, Gary L.

    1990-01-01

    The current overall safety criterion for both radioisotope and reactor power sources is containment or immobilization in the case of a reentry accident. In addition, reactors are designed to remain subcritical under conditions of land impact or water immersion. A very extensive safety test and analysis program was completed on the radioisotope thermoelectric generators (RTGs) in use on the Galileo spacecraft and planned for use on the Ulysses spacecraft. The results of this work show that the RTGs will pose little or no risk for any credible accident. The SP-100 space nuclear reactor program has begun addressing its safety criteria, and the design is planned to be such as to ensure meeting the various safety criteria. Preliminary mission risk analyses on SP-100 show the expected value population dose from postulated accidents on the reference mission to be very small. It is concluded that the current US nuclear power sources are the safest flown.

  18. Radioisotope Electric Propulsion for Fast Outer Planetary Orbiters

    NASA Technical Reports Server (NTRS)

    Oleson, Steven; Benson, Scott; Gefert, Leon; Patterson, Michael; Schreiber, Jeffrey

    2002-01-01

    Recent interest in outer planetary targets by the Office of Space Science has spurred the search for technology options to enable relatively quick missions to outer planetary targets. Several options are being explored including solar electric propelled stages combined with aerocapture at the target and nuclear electric propulsion. Another option uses radioisotope powered electric thrusters to reach the outer planets. Past work looked at using this technology to provide faster flybys. A better use for this technology is for outer planet orbiters. Combined with medium class launch vehicles and a new direct trajectory these small, sub-kilowatt ion thrusters and Stirling radioisotope generators were found to allow missions as fast as 5 to 12 years for objects from Saturn to Pluto, respectively. Key to the development is light spacecraft and science payload technologies.

  19. Outer Planet Exploration with Advanced Radioisotope Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Oleson, Steven; Gefert, Leon; Patterson, Michael; Schreiber, Jeffrey; Benson, Scott; McAdams, Jim; Ostdiek, Paul

    2002-01-01

    In response to a request by the NASA Deep Space Exploration Technology Program, NASA Glenn Research Center conducted a study to identify advanced technology options to perform a Pluto/Kuiper mission without depending on a 2004 Jupiter Gravity Assist, but still arriving before 2020. A concept using a direct trajectory with small, sub-kilowatt ion thrusters and Stirling radioisotope power systems was shown to allow the same or smaller launch vehicle class as the chemical 2004 baseline and allow a launch slip and still flyby in the 2014 to 2020 timeframe. With this promising result the study was expanded to use a radioisotope power source for small electrically propelled orbiter spacecraft for outer planet targets such as Uranus, Neptune, and Pluto.

  20. Radioisotope powered alkali metal thermoelectric converter design for space systems

    NASA Technical Reports Server (NTRS)

    Sievers, R. K.; Bankston, C. P.

    1988-01-01

    The design concept of an alkali-metal thermoelectric converter (AMTEC) for 15-30-percent-efficient conversion of heat from the General Purpose (radioisotope) Heat Source (GPHS) on spacecraft is presented. The basic physical principles of the conversion cycle are outlined; a theoretical model is derived; a modular design is described and illustrated with drawings; and the overall AMTEC/GPHS system design is characterized. Predicted performance data are presented in extensive tables and graphs and discussed in detail.

  1. Radioisotope Concentration in Lake Sediments of Maracaibo, Venezuela

    SciTech Connect

    Salas, A. Rangel; Viloria, T.; Sajo-Bohus, L.; Barros, H.; Greaves, E. D.; Palacios, D.

    2007-10-26

    Maracaibo Lake is one of the most important water basing and oil producing regions in Venezuela. Changes in the local environment have been monitored for chemical pollution in the past. For this study we selected a set of sediment samples collected in the shore and analyzed for its radioisotope content. Results show the gamma emitting isotopes distribution. Isotopes concentrations have been determined within the natural K, Th and U families.

  2. Radioisotope Concentration in Lake Sediments of Maracaibo, Venezuela

    NASA Astrophysics Data System (ADS)

    Salas, A. Rangel; Viloria, T.; Sajo-Bohus, L.; Barros, H.; Greaves, E. D.; Palacios, D.

    2007-10-01

    Maracaibo Lake is one of the most important water basing and oil producing regions in Venezuela. Changes in the local environment have been monitored for chemical pollution in the past. For this study we selected a set of sediment samples collected in the shore and analyzed for its radioisotope content. Results show the gamma emitting isotopes distribution. Isotopes concentrations have been determined within the natural K, Th and U families.

  3. Procurement of a fully licensed radioisotope thermoelectric generator transportation system

    NASA Astrophysics Data System (ADS)

    Adkins, Harold E.; Bearden, Thomas E.

    The present transportation system for radioisotope thermoelectric generators and heater units is being developed to comply with all applicable U.S. DOT regulations, including a doubly-contained 'bell jar' concept for the required double-containment of plutonium. Modifications in handling equipment and procedures are entailed by this novel packaging design, and will affect high-capacity forklifts, overhead cranes, He-backfilling equipment, etc. Attention is given to the design constraints involved, and to the Federal procurement process.

  4. Radioisotope thermoelectric generator licensed hardware package and certification tests

    NASA Astrophysics Data System (ADS)

    Goldmann, L. H.; Averette, H. S.

    1994-09-01

    This paper presents the Licensed Hardware package and the Certification Test portions of the Radioisotope Thermoelectric Generator Transportation System. This package has been designed to meet those portions of the Code of Federal Regulations (10 CFR 71) relating to 'Type B' shipments of radioactive materials. The detailed information for the anticipated license is presented in the safety analysis report for packaging, which is now in process and undergoing necessary reviews. As part of the licensing process, a full-size Certification Test Article unit, which has modifications slightly different than the Licensed Hardware or production shipping units, is used for testing. Dimensional checks of the Certification Test Article were made at the manufacturing facility. Leak testing and drop testing were done at the 300 Area of the US Department of Energy's Hanford Site near Richland, Washington. The hardware includes independent double containments to prevent the environmental spread of Pu-238, impact limiting devices to protect portions of the package from impacts, and thermal insulation to protect the seal areas from excess heat during accident conditions. The package also features electronic feed-throughs to monitor the Radioisotope Thermoelectric Generator's temperature inside the containment during the shipment cycle. This package is designed to safely dissipate the typical 4500 thermal watts produced in the largest Radioisotope Thermoelectric Generators. The package also contains provisions to ensure leak tightness when radioactive materials, such as a Radioisotope Thermoelectric Generator for the Cassini Mission, planned for 1997 by the National Aeronautics and Space Administration, are being prepared for shipment. These provisions include test ports used in conjunction with helium mass spectrometers to determine seal leakage rates of each containment during the assembly process.

  5. Radioisotope thermoelectric generator transportation system subsystem 143 software development plan

    SciTech Connect

    King, D.A.

    1994-11-10

    This plan describes the activities to be performed and the controls to be applied to the process of specifying, developing, and qualifying the data acquisition software for the Radioisotope Thermoelectric Generator (RTG) Transportation System Subsystem 143 Instrumentation and Data Acquisition System (IDAS). This plan will serve as a software quality assurance plan, a verification and validation (V and V) plan, and a configuration management plan.

  6. High-sensitivity intravascular photoacoustic imaging of lipid–laden plaque with a collinear catheter design

    PubMed Central

    Cao, Yingchun; Hui, Jie; Kole, Ayeeshik; Wang, Pu; Yu, Qianhuan; Chen, Weibiao; Sturek, Michael; Cheng, Ji-Xin

    2016-01-01

    A highly sensitive catheter probe is critical to catheter-based intravascular photoacoustic imaging. Here, we present a photoacoustic catheter probe design on the basis of collinear alignment of the incident optical wave and the photoacoustically generated sound wave within a miniature catheter housing for the first time. Such collinear catheter design with an outer diameter of 1.6 mm provided highly efficient overlap between optical and acoustic waves over an imaging depth of >6 mm in D2O medium. Intravascular photoacoustic imaging of lipid-laden atherosclerotic plaque and perivascular fat was demonstrated, where a lab-built 500 Hz optical parametric oscillator outputting nanosecond optical pulses at a wavelength of 1.7 μm was used for overtone excitation of C-H bonds. In addition to intravascular imaging, the presented catheter design will benefit other photoacoustic applications such as needle-based intramuscular imaging. PMID:27121894

  7. High-sensitivity intravascular photoacoustic imaging of lipid-laden plaque with a collinear catheter design.

    PubMed

    Cao, Yingchun; Hui, Jie; Kole, Ayeeshik; Wang, Pu; Yu, Qianhuan; Chen, Weibiao; Sturek, Michael; Cheng, Ji-Xin

    2016-01-01

    A highly sensitive catheter probe is critical to catheter-based intravascular photoacoustic imaging. Here, we present a photoacoustic catheter probe design on the basis of collinear alignment of the incident optical wave and the photoacoustically generated sound wave within a miniature catheter housing for the first time. Such collinear catheter design with an outer diameter of 1.6 mm provided highly efficient overlap between optical and acoustic waves over an imaging depth of >6 mm in D2O medium. Intravascular photoacoustic imaging of lipid-laden atherosclerotic plaque and perivascular fat was demonstrated, where a lab-built 500 Hz optical parametric oscillator outputting nanosecond optical pulses at a wavelength of 1.7 μm was used for overtone excitation of C-H bonds. In addition to intravascular imaging, the presented catheter design will benefit other photoacoustic applications such as needle-based intramuscular imaging. PMID:27121894

  8. Changes in morphology and permeability of perfused rabbit arteries during acute elevation of the intravascular pressure

    SciTech Connect

    Voino-Yasenetskaya, T.A.; Skuratovskaya, L.N.

    1986-12-01

    This paper presents a study on whether a short-term increase of intravascular pressure causes morphological injuries to the endothelium or accelerates the accumulation of /sup 125/I-labeled low-density lipoproteins (/sup 125/I-LDL) in the wall of perfused arteries of healthy rabbits, and how a raised hydrostatic pressure affects /sup 125/I-LDL transport in denuded areas of perfused arteries. The average number of cells per 1 mm/sup 2/ of luminal surface during perfusion under a pressure of 100-250 mm Hg is shown. Also, the morphology of endothelial lining of rabbit aorta under increased intravascular pressure is presented, as is the incorporation of /sup 125/I-LDL into wall of rabbit aorta under increased intravascular pressure.

  9. Generation of Radioisotopes with Accelerator Neutrons by Deuterons

    NASA Astrophysics Data System (ADS)

    Nagai, Yasuki; Hashimoto, Kazuyuki; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji; Sato, Nozomi; Kawabata, Masako; Harada, Hideo; Kin, Tadahiro; Tsukada, Kazuaki; Sato, Tetsuya K.; Minato, Futoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Seki, Yohji; Yokoyama, Kenji; Shiina, Takehiko; Ohta, Akio; Takeuchi, Nobuhiro; Kawauchi, Yukimasa; Sato, Norihito; Yamabayashi, Hisamichi; Adachi, Yoshitsugu; Kikuchi, Yuji; Mitsumoto, Toshinori; Igarashi, Takashi

    2013-06-01

    A new system proposed for the generation of radioisotopes with accelerator neutrons by deuterons (GRAND) is described by mainly discussing the production of 99Mo used for nuclear medicine diagnosis. A prototype facility of this system consists of a cyclotron to produce intense accelerator neutrons from the \\text{natC(d,n) reaction with 40 MeV 2 mA deuteron beams, and a sublimation system to separate \\text{99mTc from an irradiated 100MoO3 sample. About 8.1 TBq/week of 99Mo is produced by repeating irradiation on an enriched 100Mo sample (251 g) with accelerator neutrons for two days three times. It meets about 10% of the 99Mo demand in Japan. The characteristic feature of the system lies in its capability to reliably produce a wide variety of high-quality, carrier-free, carrier-added radioisotopes with a minimum level of radioactive waste without using uranium. The system is compact in size, and easy to operate; therefore it could be used worldwide to produce radioisotopes for medical, research, and industrial applications.

  10. NASA's Radioisotope Power Systems Planning and Potential Future Systems Overview

    NASA Technical Reports Server (NTRS)

    Zakrajsek, June F.; Woerner, Dave F.; Cairns-Gallimore, Dirk; Johnson, Stephen G.; Qualls, Louis

    2016-01-01

    The goal of NASA's Radioisotope Power Systems (RPS) Program is to make RPS ready and available to support the exploration of the solar system in environments where the use of conventional solar or chemical power generation is impractical or impossible to meet the needs of the missions. To meet this goal, the RPS Program, working closely with the Department of Energy, performs mission and system studies (such as the recently released Nuclear Power Assessment Study), assesses the readiness of promising technologies to infuse in future generators, assesses the sustainment of key RPS capabilities and knowledge, forecasts and tracks the Program's budgetary needs, and disseminates current information about RPS to the community of potential users. This process has been refined and used to determine the current content of the RPS Program's portfolio. This portfolio currently includes an effort to mature advanced thermoelectric technology for possible integration into an enhanced Multi-Mission Radioisotope Generator (eMMRTG), sustainment and production of the currently deployed MMRTG, and technology investments that could lead to a future Stirling Radioisotope Generator (SRG). This paper describes the program planning processes that have been used, the currently available MMRTG, and one of the potential future systems, the eMMRTG.

  11. Advanced radioisotope power source options for Pluto Express

    SciTech Connect

    Underwood, M.L.

    1995-12-31

    In the drive to reduce mass and cost, Pluto Express is investigating using an advanced power conversion technology in a small Radioisotope Power Source (RPS) to deliver the required mission power of 74 W(electric) at end of mission. Until this year the baseline power source under consideration has been a Radioisotope Thermoelectric Generator (RTG). This RTG would be a scaled down GPHS RTG with an inventory of 6 General Purpose Heat Sources (GPHS) and a mass of 17.8 kg. High efficiency, advanced technology conversion options are being examined to lower the power source mass and to reduce the amount of radioisotope needed. Three technologies are being considered as the advanced converter technology: the Alkali Metal Thermal-to-Electric Converter (AMTEC), Thermophotovoltaic (TPV) converters, and Stirling Engines. Conceptual designs for each of these options have been prepared. Each converter would require only 2 GPHSs to provide the mission power and would have a mass of 6.1, 7.2, and 12.4 kg for AMTEC, TPV, and Stirling Engines respectively. This paper reviews the status of each technology and the projected performance of an advanced RPS based on each technology. Based on the projected performance and spacecraft integration issues, Pluto Express would prefer to use the AMTEC based RPS. However, in addition to technical performance, selection of a power technology will be based on many other factors.

  12. Radioisotope Electric Propulsion Centaur Orbiter Spacecraft Design Overview

    NASA Technical Reports Server (NTRS)

    Oleson, Steve; McGuire, Melissa; Sarver-Verhey, Tim; Juergens, Jeff; Parkey, Tom; Dankanich, John; Fiehler, Doug; Gyekenyesi, John; Hemminger, Joseph; Gilland, Jim; Colozza, Tony; Packard, Tom; Nguyen, Thahn; Schmitz, Paul; Ostdiek, Paul; Gold, Rob; Lisse, Carey; Hibbits, Karl

    2009-01-01

    Radioisotope electric propulsion (REP) has been shown in past studies to enable missions to outerplanetary bodies including the orbiting of Centaur asteroids. Key to the feasibility for REP missions are long life, low power electric propulsion (EP) devices, low mass radioisotope power systems (RPS) and light spacecraft (S/C) components. In order to determine what are the key parameters for EP devices to perform these REP missions a design study was completed to design an REP S/C to orbit a Centaur in a New Frontiers cost cap. The design shows that an orbiter using several long lived (approximately 200 kg Xenon throughput), low power (approximately 700 W) Hall thrusters teamed with six (150 W each) Advanced Stirling Radioisotope Generators (ASRG) can deliver 60 kg of science instruments to a Centaur in 10 yr within the New Frontiers cost cap. Optimal specific impulses for the Hall thrusters were found to be around 2000 sec with thruster efficiencies over 40%. Not only can the REP S/C enable orbiting a Centaur (when compared to an all chemical mission only capable of flybys) but the additional power from the REP system can be reused to enhance science and simplify communications.

  13. Stimulus sensitive gel with radioisotope and methods of making

    DOEpatents

    Weller, Richard E.; Lind, Michael A.; Fisher, Darrell R.; Gutowska, Anna; Campbell, Allison A.

    2005-03-22

    The present invention is a thermally reversible stimulus-sensitive gel or gelling copolymer radioisotope carrier that is a linear random copolymer of an [meth-]acrylamide derivative and a hydrophilic comonomer, wherein the linear random copolymer is in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff. Addition of a biodegradable backbone and/or a therapeutic agent imparts further utility. The method of the present invention for making a thermally reversible stimulus-sensitive gelling copolymer radionuclcide carrier has the steps of: (a) mixing a stimulus-sensitive reversible gelling copolymer with an aqueous solvent as a stimulus-sensitive reversible gelling solution; and (b) mixing a radioisotope with said stimulus-sensitive reversible gelling solution as said radioisotope carrier. The gel is enhanced by either combining it with a biodegradable backbone and/or a therapeutic agent in a gelling solution made by mixing the copolymer with an aqueous solvent.

  14. Stimulus sensitive gel with radioisotope and methods of making

    DOEpatents

    Weller, Richard E [Selah, WA; Lind, Michael A [Kent, WA; Fisher, Darrell R [Richland, WA; Gutowska, Anna [Richland, WA; Campbell, Allison A [Kennewick, WA

    2001-10-02

    The present invention is a thermally reversible stimulus-sensitive gel or gelling copolymer radioisotope carrier that is a linear random copolymer of an [meth]acrylamide derivative and a hydrophilic comonomer, wherein the linear random copolymer is in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff. Addition of a biodegradable backbone and/or a therapeutic agent imparts further utility. The method of the present invention for making a thermally reversible stimulus-sensitive gelling copolymer radionuclcide carrier has the steps of: (a) mixing a stimulus-sensitive reversible gelling copolymer with an aqueous solvent as a stimulus-sensitive reversible gelling solution; and (b) mixing a radioisotope with said stimulus-sensitive reversible gelling solution as said radioisotope carrier. The gel is enhanced by either combining it with a biodegradable backbone and/or a therapeutic agent in a gelling solution made by mixing the copolymer with an aqueous solvent.

  15. Chronic biliary obstruction induces pulmonary intravascular phagocytosis and endotoxin sensitivity in rats.

    PubMed Central

    Chang, S W; Ohara, N

    1994-01-01

    Endotoxin sensitivity varies among animal species and appears to correlate with the presence of pulmonary intravascular macrophage (PIM). In rats, which lack PIM, we investigated the hypothesis that chronic cholestatic liver injury leads to induction of PIM and endotoxin sensitivity. Rats were randomized to either common bile duct ligation (BDL) or sham-surgery and studied at 1 wk (acute cholestasis), 2 wk (cholestasis, early cirrhosis), and 4 wk (cholestasis, established cirrhosis) after surgery. Intravascularly injected fluorescent latex microspheres (1 micron diameter) were taken up by large phagocytic cells in lung parenchyma of BDL rats (at 2 and 4 wk), while no uptake was observed in lungs from control rats. Electronmicroscopy revealed accumulation of large, mononuclear, macrophage-like cells containing ingested latex particles within the pulmonary capillaries. Pulmonary intravascular phagocytosis, as reflected in lung uptake of 99mTc microaggregated albumin (Microlite, mean particle diameter = 1 micron), averaged 0.7 +/- 0.1% (mean +/- SEM) of total injected dose in 13 control rats and progressively increased with time after BDL (1 wk, 1.7 +/- 0.2%; 2 wk, 10.0 +/- 3.0%; 4 wk 35.1 +/- 5.9%). Rats with biliary cirrhosis were markedly sensitive to the lethal effects of low dose endotoxin and demonstrated marked lung edema at the time of death. Furthermore, the lung uptake of intravascular 125I-lipopolysaccharide was increased five-fold in cirrhotic rats. We conclude that chronic biliary obstruction leads to the induction of pulmonary intravascular phagocytes and enhances endotoxin sensitivity in rats. Pulmonary intravascular phagocytosis in patients with advanced cirrhosis may account for their increased susceptibility to sepsis-induced adult respiratory distress syndrome. Images PMID:7962547

  16. Real-time monitoring during transportation of a radioisotope thermoelectric generator (RTG) using the radioisotope thermoelectric generator transportation system (RTGTS)

    SciTech Connect

    Pugh, B.K.

    1997-01-01

    The Radioisotopic Thermoelectric Generators (RTGs) that will be used to support the Cassini mission will be transported in the Radioisotope Thermoelectric Generator Transportation System (RTGTS). To ensure that the RTGs will not be affected during transportation, all parameters that could adversely affect RTG{close_quote}s performance must be monitored. The Instrumentation and Data Acquisition System (IDAS) for the RTGTS displays, monitors, and records all critical packaging and trailer system parameters. The IDAS also monitors the package temperature control system, RTG package shock and vibration data, and diesel fuel levels for the diesel fuel tanks. The IDAS alarms if any of these parameters reach an out-of-limit condition. This paper discusses the real-time monitoring during transportation of the Cassini RTGs using the RTGTS IDAS. {copyright} {ital 1997 American Institute of Physics.}

  17. Leiomyosarcoma of the Uterus with Intravascular Tumor Extension and Pulmonary Tumor Embolism

    SciTech Connect

    McDonald, Douglas K.; Kalva, Sanjeeva P. Fan, C.-M.; Vasilyev, Aleksandr

    2007-02-15

    We report the case of a 48-year-old woman presenting with recurrent uterine leiomyosarcoma (LMS) associated with right iliac vein and inferior vena cava (IVC) invasion and left lower lobe pulmonary tumor embolus. Because the prognosis and treatment differ from that of thrombotic pulmonary emboli, the differentiating imaging characteristics of intravascular tumor embolism are reviewed. To our knowledge, only two other cases of intravenous uterine leiomyosarcomatosis have been described in the existing literature, and this is the first reported case of the entity with associated intravascular tumor embolism.

  18. IMPACT OF OBESITY ON ENDOTOXIN-INDUCED DISSEMINATED INTRAVASCULAR COAGULATION.

    PubMed

    Duburcq, Thibault; Tournoys, Antoine; Gnemmi, Viviane; Hubert, Thomas; Gmyr, Valery; Pattou, François; Jourdain, Mercé

    2015-10-01

    An early activation of coagulation and fibrinolysis occurs during sepsis, leading to the syndrome of disseminated intravascular coagulation (DIC). Obesity has been demonstrated to be a hypercoagulable and hypofibrinolytic state, but its impact on DIC has never been studied. In this study, we aimed to determine if obesity impairs DIC in an acute endotoxic shock model using minipigs. This was a prospective, comparative, and experimental ancillary study approved by the Animal Ethics Committee. Pigs were chosen as a clinically relevant species, resembling humans in coagulation reactions. Four groups of five "Yucatan" minipigs were studied: lean and obese control groups, a lean lipopolysaccharide (LPS) group receiving Escherichia coli endotoxin (LPS), and an obese LPS group receiving the same endotoxin dose. We measured standard coagulation parameters (prothrombin time [PT], platelet count, and fibrinogen levels), thrombin-antithrombin complexes, tissue-type plasminogen activator, and plasminogen activator inhibitor-1. All measurements were performed at baseline and 30, 60, 90, 150, and 300 min. Results were given as median with interquartile ranges. At baseline, platelet count (477 [428 - 532] G/L vs. 381 [307 - 442] G/L; P = 0.005) and fibrinogen levels (4.6 [3.8 - 5.2] g/L vs. 2 [1.8 - 2.9] g/L; P < 0.001) were significantly higher, whereas PT (80% [76% - 92%] vs. 96% [89% - 100%]; P = 0.01) was significantly lower in obese pigs compared with lean pigs. In the LPS groups, administration of endotoxin resulted in a typical hypokinetic shock with DIC. The decrease in coagulation parameters (PT, platelet count, and fibrinogen levels) and the increase in thrombin-antithrombin complexes (581 [382 - 1,057] μg/mL vs. 247 [125 - 369] μg/mL at 150 min; P = 0.03) were significantly more important in the obese LPS group compared with those in the lean LPS group. Concerning the fibrinolytic reaction, we found a slightly more elevated increase of plasminogen

  19. Meta-analysis on intravascular low energy laser therapy

    NASA Astrophysics Data System (ADS)

    Zhao, Shu-Dong; Liu, Timon Cheng-Yi; Wang, Yan-Fang; Liu, Song-Hao

    2008-12-01

    Intravascular low energy laser therapy (ILELT) was put forward for cardiocirculatory diseases in USA in 1982, was popular in Russia in 1980s, and then in China in 1990s. The therapeutic effects of ILELT and drugs in comparison with drugs only on Chinese patients and their blood parameters were analyzed with meta-analyses and reported as (OR, 95%CI) for patient improvement and (WMD, 95% CI) for blood parameter improvement, where 95%CI, OR and WMD denoted 95% confidence intervals, odds ratio and weighted mean difference, respectively. It was found that the patients of cerebral infarction (2.39, 2.09~2.74) and cerebrovascular diseases (2.97, 1.69~2.53) were cured, respectively, (P < 0.01), and the symptom improvement of patients of cerebral infarction, cerebrovascular diseases and diabetes were significant (3.13, 2.79~3.51), (4.92, 3.39~7.14) , and (3.80, 2.79~5.18), and mild (3.66, 3.15~4.24), (4.95, 2.77~8.84), and (7.11, 4.54~11.13), respectively, (P < 0.01). It was also found that the blood parameters such as cholesterol (-0.78, -1.32~-0.24), total cholesterol (-1.08, -1.80~-0.36), low density lipoprotein cholesterol (-0.6, -1.01~-0.19), triacylglycerol (0.63, -0.83~-0.42), high density lipoprotein (0.34, 0.10~0.59), erythrocyte aggregation index (-0.24, -0.27~-0.21), erythrocyte Sedimentation Rate (-4.57, -7.26~-1.89), fibrinogen (-0.76, -1.31~-0.21), whole blood contrast viscosity (-0.40, -0.69~-0.12), low cut blood viscosity (-1.2, -1.93~-0.48), high cut blood viscosity (-0.62, -0.92~-0.32), whole blood viscosity(-1.2, -1.85~-0.54) and plasma blood contrast viscosity(-0.07, -0.12~-0.03) were found improved (P < 0.05). It is concluded that the patients of cerebral infarction, cerebrovascular diseases and diabetes might be improved with ILELT, which might be mediated by blood parameter improvement.

  20. Work Began on Contracts for Radioisotope Power Conversion Technology Research and Development

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.

    2005-01-01

    NASA has had a history of successful space flight missions that depended on radioisotope-fueled power systems. These Radioisotope Power Systems (RPSs) converted the heat generated from the decay of radioisotope material into useful electrical power. An RPS is most attractive in applications where photovoltaics are not optimal, such as deep-space applications where the solar flux is too low or extended applications on planets such as Mars where the day/night cycle, settling of dust, and life requirements limit the usefulness of photovoltaics. NASA s Radioisotope Power Conversion Technology (RPCT) Program is developing next-generation power-conversion technologies that will enable future missions that have requirements that cannot be met by the two RPS flight systems currently being developed by the Department of Energy for NASA: the Multi-Mission Radioisotope Thermoelectric Generator and the Stirling Radioisotope Generator (SRG).

  1. 21 CFR 880.5965 - Subcutaneous, implanted, intravascular infusion port and catheter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... port and catheter. 880.5965 Section 880.5965 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... port and catheter. (a) Identification. A subcutaneous, implanted, intravascular infusion port and... catheter is either preattached to the port or attached to the port at the time of device placement....

  2. Microfluidics in the Undergraduate Laboratory: Device Fabrication and an Experiment to Mimic Intravascular Gas Embolism

    ERIC Educational Resources Information Center

    Jablonski, Erin L.; Vogel, Brandon M.; Cavanagh, Daniel P.; Beers, Kathryn L.

    2010-01-01

    A method to fabricate microfluidic devices and an experimental protocol to model intravascular gas embolism for undergraduate laboratories are presented. The fabrication process details how to produce masters on glass slides; these masters serve as molds to pattern channels in an elastomeric polymer that can be adhered to a substrate, resulting in…

  3. Treatment of acute intravascular thrombi with diagnostic ultrasound and intravenous microbubbles.

    PubMed

    Xie, Feng; Lof, John; Everbach, Carr; He, Anming; Bennett, Richard M; Matsunaga, Terry; Johanning, Jason; Porter, Thomas R

    2009-04-01

    The purpose of this study was to determine whether high mechanical index (MI) impulses from diagnostic ultrasound (DUS) could dissolve intravascular thrombi using intravenous microbubbles. Using a canine model, DUS was applied during a continuous intravenous infusion of microbubbles. Completely thrombosed grafts were assigned to 2 treatment regimens: low-MI (<0.5-MI) ultrasound alone; or intermittent high-MI impulses (1.9-MI) guided by low-MI ultrasound (contrast pulse sequencing). A 20-MHz cavitation detector was placed confocal to the ultrasound transducer to make intravascular cavitation measurements in 1 dog. Intravascular cavitational activity was detected when an MI of >0.5 was applied. In grafts treated with intermittent high-MI ultrasound, angiographic success was 71% at 30 min and 79% at 45 min, compared with 20% and 30% at these times in the low-MI ultrasound alone group (p < 0.05). We conclude that a commercially available DUS transducer can successfully recanalize acute intravascular thrombi during a continuous microbubble infusion. PMID:19580735

  4. Research of epidermal cellular vegetal cycle of intravascular low level laser irradiation in treatment of psoriasis

    NASA Astrophysics Data System (ADS)

    Zhu, Jing; Bao, Xiaoqing; Zhang, Mei-Jue

    2005-07-01

    Objective: To research epidermal cellular vegetal cycle and the difference of DNA content between pre and post Intravascular Low Level Laser Irradiation treatment of psoriasis. Method: 15 patients suffered from psoriasis were treated by intravascular low level laser irradiation (output power: 4-5mw, 1 hour per day, a course of treatment is 10 days). We checked the different DNA content of epidermal cell between pre and post treatment of psoriasis and 8 natural human. Then the percentage of each phase among the whole cellular cycle was calculated and the statistical analysis was made. Results: The mean value of G1/S phase is obviously down while G2+M phase increased obviously. T test P<0.05.The related statistical analysis showed significant difference between pre and post treatments. Conclusions: The Intravascular Low Level Laser Irradiation (ILLLI) in treatment of psoriasis is effective according to the research of epidermal cellular vegetal cycle and the difference DNA content of Intravascular Low Level Laser Irradiation between pre and post treatment of psoriasis

  5. [Rhabdomyolysis, disseminated intravascular coagulation and multiple organ failure in a patient with cocaine and heroine poisoning].

    PubMed

    Vreugdenhil, G; Ligthart, J; de Leeuw, P W

    1992-06-20

    A 19-year-old female patient with cocaine and heroin intoxication is described in whom several life threatening complications such as hypovolemic shock, cardiopulmonary insufficiency, rhabdomyolysis, diffuse intravascular coagulation and multiple organ failure occurred. The patient survived the intoxication after quick intensive treatment.

  6. Intravascular Optical-Resolution Photoacoustic Tomography with a 1.1 mm Diameter Catheter

    PubMed Central

    Bai, Xiaosong; Gong, Xiaojing; Hau, William; Lin, Riqiang; Zheng, Jiaxiang; Liu, Chengbo; Zeng, Chengzhi; Zou, Xin; Zheng, Hairong; Song, Liang

    2014-01-01

    Photoacoustic imaging is an emerging technology that can provide anatomic, functional, and molecular information about biological tissue. Intravascular spectroscopic and molecular photoacoustic imaging can potentially improve the identification of atherosclerotic plaque composition, the detection of inflammation, and ultimately the risk stratification of atherosclerosis. In this study, a first-of-its-kind intravascular optical-resolution photoacoustic tomography (OR-PAT) system with a 1.1 mm diameter catheter is developed, offering optical-diffraction limited transverse resolution as fine as 19.6 μm, ∼10-fold finer than that of conventional intravascular photoacoustic and ultrasonic imaging. To offer complementary imaging information and depth, the system also acquires co-registered intravascular ultrasound images in parallel. Imaging of an iliac stent and a lipid phantom shows that the high resolution and contrast of OR-PAT can enable improved stent implantation guidance and lipid identification. In the future, these capabilities may ultimately improve the diagnosis and interventional treatment of vulnerable atherosclerotic plaques, which are prone to cause thrombotic complications such as myocardial infarction and stroke. PMID:24651256

  7. Radiological imaging of florid intravascular papillary endothelial hyperplasia in the mandibule: case report and literature review.

    PubMed

    Xu, Sheng-Sheng; Li, Dan

    2014-01-01

    Intravascular papillary endothelial hyperplasia was a rare benign vascular proliferative process as a result of papillary proliferation of the endothelial cells within the vessels. To our knowledge, we reported the second case occurring in the madibule, and the first reported in 1984 in the literature. We discussed manifestations of multislice computed tomography and panoramic radiography about the lesion and relevant literature was reviewed.

  8. A radioisotope powered cryobot for penetrating the Europan ice shell

    NASA Astrophysics Data System (ADS)

    Zimmerman, Wayne; Bryant, Scott; Zitzelberger, John; Nesmith, Bill

    2001-02-01

    The Cryobot team at JPL has been working on the design of a Cryo-Hydro Integrated Robotic Penetrator System (CHIRPS), which can be used to penetrate the Mars North Polar Cap or the thick sheet ice surrounding Jupiter's moon, Europa. The science for either one of these missions is compelling. For both Mars and Europa the major scientific interest is to reach regions where there is a reservoir of water that may yield signs of past or extant life. Additionally, a Mars polar cap penetration would help us understand both climatic and depositional histories for perhaps as far back as 20 million years. Similarly, penetration of the Europa ice sheet would allow scientists to unravel the mysteries surrounding the thick ice crust, its chemical composition, and subsurface ocean properties. Extreme mass and power constraints make deep drilling/coring impractical. The best way to explore either one of these environments is a cryobot mole penetrator vehicle, which carries a suite of instruments suitable for sampling and analyzing the ice or ocean environments. This paper concentrates on a Europa deep ice (i.e., kilometers thick) application of the CHIRPS, and introduces the reader to the vehicle design with focus on the use of radioisotope thermoelectric generator (RTG) technology as the primary heat (1 kW total) and power source for the robotic vehicle. Radioisotope heater unit (RHU) milli-watt power systems (120 mW total) are also employed to power the mini-radiowave ice transceivers, which are used to relay data through the ice up to the surface lander. The results of modeling and design work for both of these areas are discussed in this paper. Although radioisotope power is baselined for the Europa flight version of the cyrobot, no decision on the final design of the cryobot will be made until the environmental review process is complete. Any use of the cryobot for Mars or Europa will conform to all environmental and planetary protection requirements. .

  9. Joint Radioisotope Electric Propulsion Studies - Neptune System Explorer

    NASA Technical Reports Server (NTRS)

    Khan, M. Omair; Amini, Rashied; Ervin, Joan; Lang, Jared; Landau, Damon; Oleson, Steven; Spilker, Thomas; Strange, Nathan

    2011-01-01

    The Neptune System Explorer (NSE) mission concept study assessed opportunities to conduct Cassini-like science at Neptune with a radioisotope electric propulsion (REP) based spacecraft. REP is based on powering an electric propulsion (EP) engine with a radioisotope power source (RPS). The NSE study was commissioned under the Joint Radioisotope Electric Propulsion Studies (JREPS) project, which sought to determine the technical feasibility of flagship class REP applications. Within JREPS, special emphasis was given toward identifying tall technology tent poles, as well as recommending any new RPS technology developments that would be required for complicated REP missions. Based on the goals of JREPS, multiple RPS (e.g. thermoelectric and Stirling based RPS) and EP (e.g. Hall and ion engines) technology combinations were traded during the NSE study to determine the most favorable REP design architecture. Among the findings from the study was the need for >400We RPS systems, which was driven by EP operating powers and the requirement for a long-lived mission in the deep solar system. Additionally multiple development and implementation risks were identified for the NSE concept, as well as REP missions in general. Among the strengths of the NSE mission would be the benefits associated with RPS and EP use, such as long-term power (approx. 2-3kW) at Neptune and flexible trajectory options for achieving orbit or tours of the Neptune system. Although there are still multiple issues to mitigate, the NSE concept demonstrated distinct advantages associated with using REP for deep space flagship-class missions.

  10. Radioisotope thermoelectric generator licensed hardware package and certification tests

    NASA Astrophysics Data System (ADS)

    Goldmann, Louis H.; Averette, Henry S.

    1995-01-01

    This paper presents the Licensed Hardware package and the Certification Test portions of the Radioisitope Themoelectric Generator Transportation System. This package has been designed to meet those portions of the Code of Federal Regulations (10 CFR 71) relating to ``Type B'' shipments of radioactive materials. The licensed hardware is now in the U. S. Department of Energy licensing process that certifies the packaging's integrity under accident conditions. The detailed information for the anticipated license is presented in the safety analysis report for packaging, which is now in process and undergoing necessary reviews. As part of the licensing process, a full-size Certification Test Article unit, which has modifications slightly different than the Licensed Hardware or production shipping units, is used for testing. Dimensional checks of the Certification Test Article were made at the manufacturing facility. Leak testing and drop testing were done at the 300 Area of the U.S. Department of Energy's Hanford Site near Richland, Washington. The hardware includes independent double containments to prevent the environmental spread of 238Pu, impact limiting devices to protect portions of the package from impacts, and thermal insulation to protect the seal areas from excess heat during accident conditions. The package also features electronic feed-throughs to monitor the Radioisotope Thermoelectric Generator's temperature inside the containment during the shipment cycle. This package is designed to safely dissipate the typical 4,500 thermal watts produced in the largest Radioisotope Thermoelectric Generators. The package also contains provisions to ensure leak tightness when radioactive materials, such as a Radioisotope Thermoelectric Generator for the Cassini Mission, planned for 1997 by the National Aeronautics and Space Administration, are being prepared for shipment. These provisions include test ports used in conjunction with helium mass spectrometers to determine

  11. Milliwatt radioisotope power supply for the PASCAL Mars surface stations

    NASA Astrophysics Data System (ADS)

    Allen, Daniel T.; Murbach, Marcus S.

    2001-02-01

    A milliwatt power supply is being developed based on the 1 watt Light-Weight Radioisotope Heater Unit (RHU), which has already been used to provide heating alone on numerous spacecraft. In the past year the power supply has been integrated into the design of the proposed PASCAL Mars Network Mission, which is intended to place 24 surface climate monitoring stations on Mars. The PASCAL Mars mission calls for the individual surface stations to be transported together in one spacecraft on a trajectory direct from launch to orbit around Mars. From orbit around Mars each surface station will be deployed on a SCRAMP (slotted compression ramp) probe and, after aerodynamic and parachute deceleration, land at a preselected location on the planet. During descent sounding data and still images will be accumulated, and, once on the surface, the station will take measurements of pressure, temperature and overhead atmospheric optical depth for a period of 10 Mars years (18.8 Earth years). Power for periodic data acquisition and transmission to orbital then to Earth relay will come from a bank of ultracapacitors which will be continuously recharged by the radioisotope power supply. This electronic system has been designed and a breadboard built. In the ultimate design the electronics will be arrayed on the exterior surface of the radioisotope power supply in order to take advantage of the reject heat. This assembly in turn is packaged within the SCRAMP, and that assembly comprises the surface station. An electrically heated but otherwise prototypical power supply was operated in combination with the surface station breadboard system, which included the ultracapacitors. Other issues addressed in this work have been the capability of the generator to withstand the mechanical shock of the landing on Mars and the effectiveness of the generator's multi-foil vacuum thermal insulation. .

  12. Radioisotope Stirling Generator Options for Pluto Fast Flyby Mission

    SciTech Connect

    Schock, Alfred

    2012-01-19

    The preceding paper described conceptual designs and analytical results for five Radioisotope Thermoelectric Generator (RTG) options for the Pluto Fast Flyby (PFF) mission, and the present paper describes three Radioisotope Stirling Generator (RSG) options for the same mission. The RSG options are based on essentially the same radioisotope heat source modules used in previously flown RTGs and on designs and analyses of a 75-watt free-piston Stirling engine produced by Mechanical Technology Incorporated (MTI) for NASA's Lewis Research Center. The integrated system design options presented were generated in a Fairchild Space study sponsored by the Department of Energy's Office of Special Applications, in support of ongoing PFF mission and spacecraft studies that the Jet Propulsion Laboratory (JPL) is conducting for the National Aeronautics and Space Administration (NASA). That study's NASA-directed goal is to reduce the spacecraft mass from its baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for a power source able to deliver 69 watts(e) at the end of the 9.2-year mission. In general, the Stirling options were found to be lighter than the thermoelectric options described in the preceding paper. But they are less mature, requiring more development, and entailing greater programmatic risk. The Stirling power system mass ranged from 7.3 kg (well below the 10-kg goal) for a non-redundant system to 11.3 kg for a redundant system able to maintain full power if one of its engines fails. In fact, the latter system could deliver as much as 115 watts(e) if desired by the mission planners. There are 2 copies in the file.

  13. Radioisotope Stirling Generator Options for Pluto Fast Flyby Mission

    SciTech Connect

    Schock, Alfred

    1993-10-01

    The preceding paper described conceptual designs and analytical results for five Radioisotope Thermoelectric Generator (RTG) options for the Pluto Fast Flyby (PFF) mission, and the present paper describes three Radioisotope Stirling Generator (RSG) options for the same mission. The RSG options are based on essentially the same radioisotope heat source modules used in previously flown RTGs and on designs and analyses of a 75-watt free-piston Stirling engine produced by Mechanical Technology Incorporated (MTI) for NASA's Lewis Research Center. The integrated system design options presented were generated in a Fairchild Space study sponsored by the Department of Energy's Office of Special Applications, in support of ongoing PFF mission and spacecraft studies that the Jet Propulsion Laboratory (JPL) is conducting for the National Aeronautics and Space Administration (NASA). That study's NASA-directed goal is to reduce the spacecraft mass from its baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for a power source able to deliver 69 watts(e) at the end of the 9.2-year mission. In general, the Stirling options were found to be lighter than the thermoelectric options described in the preceding paper. But they are less mature, requiring more development, and entailing greater programmatic risk. The Stirling power system mass ranged from 7.3 kg (well below the 10-kg goal) for a non-redundant system to 11.3 kg for a redundant system able to maintain full power if one of its engines fails. In fact, the latter system could deliver as much as 115 watts(e) if desired by the mission planners. There are 5 copies in the file.

  14. The nurse's role in delivery of radioisotope for ictal SPECT scan.

    PubMed

    Huntington, N A

    1999-08-01

    The Medical College of Georgia Hospital and Clinics (MCG) was one of the first centers in the United States (US) to institute a video electroencephalography (EEG) epilepsy monitoring unit and epilepsy surgery program. In order to surgically remove the area in the brain giving rise to seizures, the epileptogenic zone must be identified and localized. One of the newer methods used to identify the epileptogenic seizure focus is the ictal Single Photon Emission Computed Tomography (SPECT) scan, which MCG began performing in 1993. The nurses staffing the six bed Epilepsy Monitoring Unit (EMU) are trained by the Nuclear Radiology Department and Radiation Safety Officer to bandle the radioisotope during mixing, calibration and injection. The bedside nursing protocol developed assures patient and staff radiation safety and efficacious injection. Over 300 patients have been injected by nurses with a high degree of safety to patients and staff. This has resulted in positive scans that aid diagnosis. The success of the ictal SPECT protocol can be attributed to the active collaboration of our multidisciplinary team.

  15. Optical imaging of radioisotopes: a novel multimodal approach to molecular imaging.

    PubMed

    Spinelli, A E; Marengo, M; Calandrino, R; Sbarbati, A; Boschi, F

    2012-06-01

    In this review there will be presented an overview of the literature about the recent developments on radiotracers imaging using optical methods and their applications. We will begin with a short summary regarding the discovery of Cerenkov radiation (CR) and then focus on the early developments and experimental validation of planar Cerenkov luminescence imaging. A significant improvement in Cerenkov luminescence imaging was given by the development of tomographic methods in order to obtain in vivo whole body 3D images of Cerenkov sources. An interesting and original application discussed in this review is the use of CR as the excitation source of quantum dots and fluorophores. We will also present some recent experimental results on in vivo radio luminescence imaging of alpha and gamma emitters. All these results make optical radioisotopes imaging an interesting cost-effective tool for the screening of new probes for both imaging and therapeutic applications. Other interesting aspects are the uses of Cerenkov radiation for radiotherapy and for radiopharmaceuticals synthesis applications. We will conclude by summarising the most important results and the future challenges. PMID:22695338

  16. NASA GRC Technology Development Project for a Stirling Radioisotope Power System

    NASA Technical Reports Server (NTRS)

    Thieme, Lanny G.; Schreiber, Jeffrey G.

    2000-01-01

    NASA Glenn Research Center (GRC), the Department of Energy (DOE), and Stirling Technology Company (STC) are developing a Stirling convertor for an advanced radioisotope power system to provide spacecraft on-board electric power for NASA deep space missions. NASA GRC is conducting an in-house project to provide convertor, component, and materials testing and evaluation in support of the overall power system development. A first characterization of the DOE/STC 55-We Stirling Technology Demonstration Convertor (TDC) under the expected launch random vibration environment was recently completed in the NASA GRC Structural Dynamics Laboratory. Two TDCs also completed an initial electromagnetic interference (EMI) characterization at NASA GRC while being tested in a synchronized, opposed configuration. Materials testing is underway to support a life assessment of the heater head, and magnet characterization and aging tests have been initiated. Test facilities are now being established for an independent convertor performance verification and technology development. A preliminary Failure Mode Effect Analysis (FMEA), initial finite element analysis (FEA) for the linear alternator, ionizing radiation survivability assessment, and radiator parametric study have also been completed. This paper will discuss the status, plans, and results to date for these efforts.

  17. Final Progress Report: Isotope Identification Algorithm for Rapid and Accurate Determination of Radioisotopes Feasibility Study

    SciTech Connect

    Rawool-Sullivan, Mohini; Bounds, John Alan; Brumby, Steven P.; Prasad, Lakshman; Sullivan, John P.

    2012-04-30

    This is the final report of the project titled, 'Isotope Identification Algorithm for Rapid and Accurate Determination of Radioisotopes,' PMIS project number LA10-HUMANID-PD03. The goal of the work was to demonstrate principles of emulating a human analysis approach towards the data collected using radiation isotope identification devices (RIIDs). It summarizes work performed over the FY10 time period. The goal of the work was to demonstrate principles of emulating a human analysis approach towards the data collected using radiation isotope identification devices (RIIDs). Human analysts begin analyzing a spectrum based on features in the spectrum - lines and shapes that are present in a given spectrum. The proposed work was to carry out a feasibility study that will pick out all gamma ray peaks and other features such as Compton edges, bremsstrahlung, presence/absence of shielding and presence of neutrons and escape peaks. Ultimately success of this feasibility study will allow us to collectively explain identified features and form a realistic scenario that produced a given spectrum in the future. We wanted to develop and demonstrate machine learning algorithms that will qualitatively enhance the automated identification capabilities of portable radiological sensors that are currently being used in the field.

  18. In situ 19F MRS measurement of RIF-1 tumor blood volume: corroboration by radioisotope-labeled [125I]-albumin and correlation to tumor size.

    PubMed

    Baldwin, N J; Wang, Y; Ng, T C

    1996-01-01

    Tumor blood volume (TBV) is an important factor in the metabolism of a tumor and in its response to therapy. Until recently, the only methods to determine TBV were highly invasive and many involved radioisotopes. In this study, a perfluorocarbon (PFC) emulsion, Oxypherol, was monitored by 19F magnetic resonance spectroscopy (MRS). TBVs as determined by 19F MRS of in situ and excised radiation-induced fibrosarcoma (RIF-1) tumors (n = 9), were strongly correlated with the TBV measured by a radioisotope labeled albumin method (slopes of 1.1 and 0.8 with R = 0.86 and 0.91, respectively, by linear regression). In general, the TBV as calculated from the in situ MRS measurements (n = 24) decreased from 28 to 5 ml/100 g tumor mass for tumors ranging in mass from 0.15 to 2 g. However, there was an indication of an initial increase of TBV in tumors smaller than 0.5 g.

  19. Radioisotope bone scanning in a case of sarcoidosis

    SciTech Connect

    Cinti, D.C.; Hawkins, H.B.; Slavin, J.D. Jr.

    1985-03-01

    The application of radioisotope scanning to osseous involvement from systemic sarcoidosis has been infrequently described in the scientific literature. Most commonly, the small bones of the hands and feet are affected if sarcoidosis involves the skeleton. Nonetheless, there are also occasional manifestations of sarcoid in the skull, long bones, and vertebral bodies. This paper describes a case of sarcoid involving the lung parenchyma with multiple lesions in the skull and ribs demonstrated by bone scanning with Tc-99m MDP. Following treatment with steroids, the bone scan showed complete resolution of the rib lesions and almost complete resolution of the lesions in the calvarium.

  20. Analytical predictions of RTG power degradation. [Radioisotope Thermoelectric Generator

    NASA Technical Reports Server (NTRS)

    Noon, E. L.; Raag, V.

    1979-01-01

    The DEGRA computer code that is based on a mathematical model which predicts performance and time-temperature dependent degradation of a radioisotope thermoelectric generator is discussed. The computer code has been used to predict performance and generator degradation for the selenide Ground Demonstration Unit (GDS-1) and the generator used in the Galileo Project. Results of parametric studies of load voltage vs generator output are examined as well as the I-V curve and the resulting predicted power vs voltage. The paper also discusses the increased capability features contained in DEGRA2 and future plans for expanding the computer code performance.

  1. Rhenium-188--a generator-derived radioisotope for cancer therapy.

    PubMed

    Knapp, F F

    1998-10-01

    Rhenium-188 (188Re) is an important therapeutic radioisotope which is obtained on demand as carrier-free sodium perrhenate by saline elution of the tungsten-188/rhenium-188 generator system. With a half-life of 16.9 hours and emission of a high energy beta particle (maximal energy of 2.12 MeV) and a gamma photon (155 keV, 15%) for imaging, 188Re can be provided at reasonable costs for routine preparation of radiopharmaceuticals for cancer treatment. PMID:10851424

  2. ADVANCED RADIOISOTOPE HEAT SOURCE AND PROPULSION SYSTEMS FOR PLANETARY EXPLORATION

    SciTech Connect

    R. C. O'Brien; S. D. Howe; J. E. Werner

    2010-09-01

    The exploration of planetary surfaces and atmospheres may be enhanced by increasing the range and mobility of a science platform. Fundamentally, power production and availability of resources are limiting factors that must be considered for all science and exploration missions. A novel power and propulsion system is considered and discussed with reference to a long-range Mars surface exploration mission with in-situ resource utilization. Significance to applications such as sample return missions is also considered. Key material selections for radioisotope encapsulation techniques are presented.

  3. Parametric System Model for a Stirling Radioisotope Generator

    NASA Technical Reports Server (NTRS)

    Schmitz, Paul C.

    2015-01-01

    A Parametric System Model (PSM) was created in order to explore conceptual designs, the impact of component changes and power level on the performance of the Stirling Radioisotope Generator (SRG). Using the General Purpose Heat Source (GPHS approximately 250 Wth) modules as the thermal building block from which a SRG is conceptualized, trade studies are performed to understand the importance of individual component scaling on isotope usage. Mathematical relationships based on heat and power throughput, temperature, mass, and volume were developed for each of the required subsystems. The PSM uses these relationships to perform component- and system-level trades.

  4. Parametric System Model for a Stirling Radioisotope Generator

    NASA Technical Reports Server (NTRS)

    Schmitz, Paul C.

    2014-01-01

    A Parametric System Model (PSM) was created in order to explore conceptual designs, the impact of component changes and power level on the performance of Stirling Radioisotope Generator (SRG). Using the General Purpose Heat Source (GPHS approximately 250 watt thermal) modules as the thermal building block around which a SRG is conceptualized, trade studies are performed to understand the importance of individual component scaling on isotope usage. Mathematical relationships based on heat and power throughput, temperature, mass and volume were developed for each of the required subsystems. The PSM uses these relationships to perform component and system level trades.

  5. Evaluation of Intravascular Hemolysis With Erythrocyte Creatine in Patients With Aortic Stenosis.

    PubMed

    Sugiura, Tetsuro; Okumiya, Toshika; Kubo, Toru; Takeuchi, Hiroaki; Matsumura, Yoshihisa

    2016-07-27

    Chronic intravascular hemolysis has been identified in patients with cardiac valve prostheses, but only a few case reports have evaluated intravascular hemolysis in patients with native valvular heart disease. To detect intravascular hemolysis in patients with aortic stenosis, erythrocyte creatine was evaluated with hemodynamic indices obtained by echocardiography.Erythrocyte creatine, a marker of erythrocyte age, was assayed in 30 patients with aortic stenosis and 10 aged matched healthy volunteers. Peak flow velocity of the aortic valve was determined by continuous-wave Doppler echocardiography. Twenty of 30 patients with aortic stenosis had high erythrocyte creatine levels (> 1.8 µmol/g Hb) and erythrocyte creatine was significantly higher as compared with control subjects (1.98 ± 0.49 versus 1.52 ± 0.19 µmol/g Hb, P = 0.007). Peak transvalvular pressure gradient ranged from 46 to 142 mmHg and peak flow velocity ranged from 3.40 to 5.95 m/second. Patients with aortic stenosis had a significantly lower erythrocyte count (387 ± 40 versus 436 ± 42 × 10(4) µL, P = 0.002) and hemoglobin (119 ± 11 versus 135 ± 11 g/L, P < 0.001) as compared with control subjects. Erythrocyte creatine had a fair correlation with peak flow velocity (r = 0.55, P = 0.002).In conclusion, intravascular hemolysis due to destruction of erythrocytes was detected in patients with moderate to severe aortic stenosis and the severity of intravascular hemolysis was related to valvular flow velocity of the aortic valve.

  6. Asphyxia by Drowning Induces Massive Bleeding Due To Hyperfibrinolytic Disseminated Intravascular Coagulation

    PubMed Central

    Schwameis, Michael; Schober, Andreas; Schörgenhofer, Christian; Sperr, Wolfgang Reinhard; Schöchl, Herbert; Janata-Schwatczek, Karin; Kürkciyan, Erol Istepan; Sterz, Fritz

    2015-01-01

    Objective: To date, no study has systematically investigated the impact of drowning-induced asphyxia on hemostasis. Our objective was to test the hypothesis that asphyxia induces bleeding by hyperfibrinolytic disseminated intravascular coagulation. Design: Observational study. Setting: A 2,100-bed tertiary care facility in Vienna, Austria, Europe. Patients: All cases of drowning-induced asphyxia (n = 49) were compared with other patients with cardiopulmonary resuscitation (n = 116) and to patients with acute promyelocytic leukemia (n = 83). Six drowning victims were investigated prospectively. To study the mechanism, a forearm-ischemia model was used in 20 volunteers to investigate whether hypoxia releases tissue plasminogen activator. Interventions: None. Measurements and Main Results: Eighty percent of patients with drowning-induced asphyxia developed overt disseminated intravascular coagulation within 24 hours. When compared with nondrowning cardiac arrest patients, drowning patients had a 13 times higher prevalence of overt disseminated intravascular coagulation at admission (55% vs 4%; p < 0.001). Despite comparable disseminated intravascular coagulation scores, acute promyelocytic leukemia patients had higher fibrinogen but lower d-dimer levels and platelet counts than drowning patients (p < 0.001). Drowning victims had a three-fold longer activated partial thromboplastin time (124 s; p < 0.001) than both nondrowning cardiac arrest and acute promyelocytic leukemia patients. Hyperfibrinolysis was reflected by up to 1,000-fold increased d-dimer levels, greater than 5-fold elevated plasmin antiplasmin levels, and a complete absence of thrombelastometric clotting patterns, which was reversed by antifibrinolytics and heparinase. Thirty minutes of forearm-ischemia increased tissue plasminogen activator 31-fold (p < 0.001). Conclusions: The vast majority of drowning patients develops overt hyperfibrinolytic disseminated intravascular coagulation, partly caused by

  7. Intravascular pressure augments cerebral arterial constriction by inducing voltage-insensitive Ca2+ waves.

    PubMed

    Mufti, Rania E; Brett, Suzanne E; Tran, Cam Ha T; Abd El-Rahman, Rasha; Anfinogenova, Yana; El-Yazbi, Ahmed; Cole, William C; Jones, Peter P; Chen, S R Wayne; Welsh, Donald G

    2010-10-15

    This study examined whether elevated intravascular pressure stimulates asynchronous Ca(2+) waves in cerebral arterial smooth muscle cells and if their generation contributes to myogenic tone development. The endothelium was removed from rat cerebral arteries, which were then mounted in an arteriograph, pressurized (20-100 mmHg) and examined under a variety of experimental conditions. Diameter and membrane potential (V(M)) were monitored using conventional techniques; Ca(2+) wave generation and myosin light chain (MLC(20))/MYPT1 (myosin phosphatase targeting subunit) phosphorylation were assessed by confocal microscopy and Western blot analysis, respectively. Elevating intravascular pressure increased the proportion of smooth muscle cells firing asynchronous Ca(2+) waves as well as event frequency. Ca(2+) wave augmentation occurred primarily at lower intravascular pressures (<60 mmHg) and ryanodine, a plant alkaloid that depletes the sarcoplasmic reticulum (SR) of Ca(2+), eliminated these events. Ca(2+) wave generation was voltage insensitive as Ca(2+) channel blockade and perturbations in extracellular [K(+)] had little effect on measured parameters. Ryanodine-induced inhibition of Ca(2+) waves attenuated myogenic tone and MLC(20) phosphorylation without altering arterial V(M). Thapsigargin, an SR Ca(2+)-ATPase inhibitor also attenuated Ca(2+) waves, pressure-induced constriction and MLC(20) phosphorylation. The SR-driven component of the myogenic response was proportionally greater at lower intravascular pressures and subsequent MYPT1 phosphorylation measures revealed that SR Ca(2+) waves facilitated pressure-induced MLC(20) phosphorylation through mechanisms that include myosin light chain phosphatase inhibition. Cumulatively, our findings show that mechanical stimuli augment Ca(2+) wave generation in arterial smooth muscle and that these transient events facilitate tone development particularly at lower intravascular pressures by providing a proportion of the Ca

  8. The Monte Carlo-Based Dosimetry of Beta Emitters for Intravascular Brachytherapy

    SciTech Connect

    Choi, C.K.; Son, J.; Ye, S.J.

    2001-06-17

    Intravascular brachytherapy (IVBT) is a new radiotherapy modality to prevent restenosis (re-blockage of the coronary artery) following interventional coronary angioplasty. It is estimated that the restenosis rate may drop from {approx}35 to 40% to well below 10% if radiation is delivered to the obstruction site during or after angioplasty. In traditional brachytherapy, the dose is typically specified at 1 cm from the source, and the effects of low-energy photons and secondary electrons are essentially ignored. In IVBT, however, the entire lesion may be 1 to 3 mm in thickness. A better understanding of dosimetry in the millimetre range will help in the development of optimum clinical devices and their efficacious use in different institutions using different radionuclides and devices. The actual treatment geometry consists of an encapsulated train of seeds, a guide wire, and a stent in a curved vessel. The source is a cylindrical train of 12 source seeds, each having dimensions of 0.64 mm in diameter and 2.5 mm in length, and proximal/distal gold markers. Each seed contains {sup 90}Sr/Y mixed with fired ceramic encapsulated in a 0.04-mm stainless steel wall. The Monte Carlo simulations are carried out for the trained source geometries in the linear and curved vessels with and without a stent. The stent structure is approximately modeled as a set of tori with a rotational radius of 1.92 mm from the source axis and a circular radius of 0.08 mm in cross section. Five tori are equally spaced for each seed. The stent shadows 31% of the total area of the source surface. The total activity of 70 mCi (2.59 x 10{sup 9} Bq) was chosen from manufacturer data. The corresponding mass fraction of {sup 90}Sr/Y in the source ceramic is negligible and was not explicitly included in the MCNP simulations. All tallies were multiplied with 5.83 mCi/seed x 3.7 x 10{sup 7} s/mCi for one active seed, and then the tallies that made contributions to the dose in a voxel of interest were

  9. GRC Supporting Technology for NASA's Advanced Stirling Radioisotope Generator (ASRG)

    NASA Technical Reports Server (NTRS)

    Schreiber, Jeffrey G.; Thieme, Lanny G.

    2008-01-01

    From 1999 to 2006, the NASA Glenn Research Center (GRC) supported a NASA project to develop a high-efficiency, nominal 110-We Stirling Radioisotope Generator (SRG110) for potential use on NASA missions. Lockheed Martin was selected as the System Integration Contractor for the SRG110, under contract to the Department of Energy (DOE). The potential applications included deep space missions, and Mars rovers. The project was redirected in 2006 to make use of the Advanced Stirling Convertor (ASC) that was being developed by Sunpower, Inc. under contract to GRC, which would reduce the mass of the generator and increase the power output. This change would approximately double the specific power and result in the Advanced Stirling Radioisotope Generator (ASRG). The SRG110 supporting technology effort at GRC was replanned to support the integration of the Sunpower convertor and the ASRG. This paper describes the ASRG supporting technology effort at GRC and provides details of the contributions in some of the key areas. The GRC tasks include convertor extended-operation testing in air and in thermal vacuum environments, heater head life assessment, materials studies, permanent magnet characterization and aging tests, structural dynamics testing, electromagnetic interference and electromagnetic compatibility characterization, evaluation of organic materials, reliability studies, and analysis to support controller development.

  10. Retention of Radium-225 and Its Daughter Radioisotopes in Bone

    SciTech Connect

    Mirzadeh, Saed; Garland, Marc A; Kennel, Steve J

    2008-01-01

    The natural bone seeking tendency of Ra+2, similar to the other alkali metal ions, coupled with the short range high LET of -particle emissions are an ideal combination for localized therapy, and recently 11.4 d 223Ra has been studied for therapy of bone tumors in rats and humans [1,2]. Actinium-225 is also an attractive radioisotope for endo-radiotherapy in a single decay chain from 225Ac, over 26 MeV (~70% of total) is carried by four - particles ranging in energy from 5.7 to 8.4 MeV [3,4]. Although Ac+3 does not home naturally to bone (rather to liver) [5,6], its parent, 225Ra ( -, t1/2 = 15 d), can be used as an in vivo source for 225Ac. A pivotal question for the 225Ra/225Ac in vivo generator system is whether translocation of the daughter nuclei occurs prior to or following the uptake of 225Ra by the bone. In order to assess potential collateral damage to soft tissue organs it is essential to quantitate the extent to which 225Ac is retained in organs following the uptake of 225Ra. We have attempted to answer these questions by investigating the extent of translocation of 225Ac and 213Bi, two daughter radioisotopes of 225Ra, following retention of initially pure 225Ra in bone in normal mice.

  11. GRC Supporting Technology for NASA's Advanced Stirling Radioisotope Generator (ASRG)

    NASA Astrophysics Data System (ADS)

    Schreiber, Jeffrey G.; Thieme, Lanny G.

    2008-01-01

    From 1999-2006, the Glenn Research Center (GRC) supported a NASA project to develop a high-efficiency, nominal 110-We Stirling Radioisotope Generator (SRG110) for potential use on NASA missions. Lockheed Martin was selected as the System Integration Contractor for the SRG110, under contract to the Department of Energy (DOE). The potential applications included deep space missions, and Mars rovers. The project was redirected in 2006 to make use of the Advanced Stirling Convertor (ASC) that was being developed by Sunpower, Inc. under contract to GRC, which would reduce the mass of the generator and increase the power output. This change would approximately double the specific power and result in the Advanced Stirling Radioisotope Generator (ASRG). The SRG110 supporting technology effort at GRC was replanned to support the integration of the Sunpower convertor and the ASRG. This paper describes the ASRG supporting technology effort at GRC and provides details of the contributions in some of the key areas. The GRC tasks include convertor extended-operation testing in air and in thermal vacuum environments, heater head life assessment, materials studies, permanent magnet characterization and aging tests, structural dynamics testing, electromagnetic interference and electromagnetic compatibility characterization, evaluation of organic materials, reliability studies, and analysis to support controller development.

  12. Radioisotope Thermoelectric Generator Options for Pluto Fast Flyby Mission

    NASA Astrophysics Data System (ADS)

    Schock, Alfred

    1994-07-01

    A small spacecraft design for the Pluto Fast Flyby (PFF) mission is under study by the Jet Propulsion Laboratory (PL) for the National Aeronautics and Space Administration (NASA), for a possible launch as early as 1998. JPL's 1992 baseline design calls for a power source able to furnish an energy output of 3963 kWh and a power output of 69 Watts(e) at the end of the 9.2-year mission. Satisfying those demands is made difficult because NASA management has set a goal of reducing the spacecraft mass from a baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for the power source. To support the ongoing NASA/JPL studies, the Department of Energy's Office of Special Applications (DOE/OSA) commissioned Fairchild Space to prepare and analyze conceptual designs of radioisotope power systems for the PFF mission. Thus far, a total of eight options employing essentially the same radioisotope heat source modules were designed and subjected to thermal, electrical, structural, and mass analyses by Fairchild. Five of these - employing thermoelectric converters - are described in the present paper, and three - employing free-piston Stirling converters - are described in the companion paper presented next. The system masses of the thermoelectric options ranged from 19.3 kg to 10.2 kg. In general, the options requiring least development are the heaviest, and the lighter options require more development with greater programmatic risk.

  13. Multi-Watt Small Radioisotope Thermoelectric Generator Conceptual Design Study

    NASA Astrophysics Data System (ADS)

    Determan, William R.; Otting, William; Frye, Patrick; Abelson, Robert; Ewell, Richard; Miyake, Bob; Synder, Jeff

    2007-01-01

    A need has been identified for a small, light-weight, reliable power source using a radioisotope heat source, to power the next generation of NASA's small surface rovers and exploration probes. Unit performance, development costs, and technical risk are key criteria to be used to select the best design approach. Because safety can be a major program cost and schedule driver, RTG designs should utilize the DOE radioisotope safety program's data base to the maximum extent possible. Other aspects important to the conceptual design include: 1) a multi-mission capable design for atmospheric and vacuum environments, 2) a module size based on one GPHS Step 2 module, 3) use of flight proven thermoelectric converter technologies, 4) a long service lifetime of up to 14 years, 5) maximize unit specific power consistent with all other requirements, and 6) be ready by 2013. Another critical aspect of the design is the thermal integration of the RTG with the rover or probe's heat rejection subsystem and the descent vehicle's heat rejection subsystem. This paper describes two multi-watt RTG design concepts and their integration with a MER-class rover.

  14. An overview of the Radioisotope Thermoelectric Generator Transporation System Program

    SciTech Connect

    McCoy, J.C.

    1995-10-01

    Radioisotope Thermoelectric Generators (RTG) convert the heat generated by radioactive decay to electricity using thermocouples. RTGs have a long operating life, are reasonably lightweight, and require little or no maintenance once assembled and tested. These factors make RTGs particularly attractive for use in spacecraft However, because RTGs contain significant quantities of radioactive materials, normally plutonium-238 and its decay products, they must be transported in packages built in accordance with Title 10, Code of Federal Regulations, Part 71. The US Department of Energy assigned the Radioisotope Thermoelectric Generator Transportation System (RTGTS) Program to Westinghouse Hanford Company in 1988 to develop a system meeting the regulatory requirements. The program objective was to develop a transportation system that would fully comply with 10 CFR 71 while protecting RTGs from adverse environmental conditions during normal conditions of transport (e.g., shock and heat). The RTGTS is scheduled for completion in December 1996 and will be available to support the National Aeronautics and Space Administrations Cassini mission to Saturn in October 1997. This paper provides an overview of the RTGTS and discusses the hardware being produced. Additionally, various program management innovations mandated by recent ma or changes in the US Department of Energy structure and resources will be outlined.

  15. Technology Development for a Stirling Radioisotope Power System

    NASA Technical Reports Server (NTRS)

    Thieme, Lanny G.; Qiu, Songgang; White, Maurice A.

    2000-01-01

    NASA Glenn Research Center and the Department of Energy are developing a Stirling convertor for an advanced radioisotope power system to provide spacecraft on-board electric power for NASA deep space missions. NASA Glenn is addressing key technology issues through the use of two NASA Phase II SBIRs with Stirling Technology Company (STC) of Kennewick, WA. Under the first SBIR, STC demonstrated a synchronous connection of two thermodynamically independent free-piston Stirling convertors and a 40 to 50 fold reduction in vibrations compared to an unbalanced convertor. The second SBIR is for the development of an Adaptive Vibration Reduction System (AVRS) that will essentially eliminate vibrations over the mission lifetime, even in the unlikely event of a failed convertor. This paper presents the status and results for these two SBIR projects and also discusses a new NASA Glenn in-house project to provide supporting technology for the overall Stirling radioisotope power system development. Tasks for this new effort include convertor performance verification, controls development, heater head structural life assessment, magnet characterization and thermal aging tests, FEA analysis for a lightweight alternator concept, and demonstration of convertor operation under launch and orbit transfer load conditions.

  16. Radioisotope Electric Propulsion for Deep Space Sample Return

    SciTech Connect

    Noble, Robert J.; /SLAC

    2009-07-14

    The need to answer basic questions regarding the origin of the Solar System will motivate robotic sample return missions to destinations like Pluto, its satellite Charon, and objects in the Kuiper belt. To keep the mission duration short enough to be of interest, sample return from objects farther out in the Solar System requires increasingly higher return velocities. A sample return mission involves several complicated steps to reach an object and obtain a sample, but only the interplanetary return phase of the mission is addressed in this paper. Radioisotope electric propulsion is explored in this parametric study as a means to propel small, dedicated return vehicles for transferring kilogram-size samples from deep space to Earth. Return times for both Earth orbital rendezvous and faster, direct atmospheric re-entry trajectories are calculated for objects as far away as 100 AU. Chemical retro-rocket braking at Earth is compared to radioisotope electric propulsion but the limited deceleration capability of chemical rockets forces the return trajectories to be much slower.

  17. Strontium Iodide Instrument Development for Gamma Spectroscopy and Radioisotope Identification

    SciTech Connect

    Beck, P; Cherepy, Nerine; Payne, Stephen A.; Swanberg, E.; Nelson, K.; Thelin, P; Fisher, S E; Hunter, Steve; Wihl, B; Shah, Kanai; Hawrami, Rastgo; Burger, Arnold; Boatner, Lynn A; Momayezi, M; Stevens, K; Randles, M H; Solodovnikov, D

    2014-01-01

    Development of the Europium-doped Strontium Iodide scintillator, SrI2(Eu), has progressed significantly in recent years. SrI2(Eu) has excellent material properties for gamma ray spectroscopy: high light yield (>80,000 ph/MeV), excellent light yield proportionality, and high effective atomic number (Z=49) for high photoelectric cross-section. High quality 1.5 and 2 diameter boules are now available due to rapid advances in SrI2(Eu) crystal growth. In these large SrI2(Eu) crystals, optical self-absorption by Eu2+ degrades the energy resolution as measured by analog electronics, but we mitigate this effect through on-the-fly correction of the scintillation pulses by digital readout electronics. Using this digital correction technique we have demonstrated energy resolution of 2.9% FWHM at 662 keV for a 4 in3 SrI2(Eu) crystal, over 2.6 inches long. Based on this digital readout technology, we have developed a detector prototype with greatly improved radioisotope identification capability compared to Sodium Iodide, NaI(Tl). The higher resolution of SrI2(Eu) yields a factor of 2 to 5 improvement in radioisotope identification (RIID) error rate compared to NaI(Tl).

  18. Technology development for a Stirling radioisotope power system

    NASA Astrophysics Data System (ADS)

    Thieme, Lanny G.; Qiu, Songgang; White, Maurice A.

    2000-01-01

    NASA Glenn Research Center and the Department of Energy are developing a Stirling convertor for an advanced radioisotope power system to provide spacecraft on-board electric power for NASA deep space missions. NASA Glenn is addressing key technology issues through the use of two NASA Phase II SBIRs with Stirling Technology Company (STC) of Kennewick, WA. Under the first SBIR, STC demonstrated a synchronous connection of two thermodynamically independent free-piston Stirling convertors and a 40 to 50 fold reduction in vibrations compared to an unbalanced convertor. The second SBIR is for the development of an Adaptive Vibration Reduction System (AVRS) that will essentially eliminate vibrations over the mission lifetime, even in the unlikely event of a failed convertor. This paper presents the status and results for these two SBIR projects and also discusses a new NASA Glenn in-house project to provide supporting technology for the overall Stirling radioisotope power system development. Tasks for this new effort include convertor performance verification, controls development, heater head structural life assessment, magnet characterization and thermal aging tests, FEA analysis for a lightweight alternator concept, and demonstration of convertor operation under launch and orbit transfer load conditions. .

  19. An overview of the Radioisotope Thermoelectric Generator Transportation System Program

    SciTech Connect

    McCoy, J.C.; Becker, D.L.

    1996-03-01

    Radioisotope Thermoelectric Generators (RTG) convert the heat generated by radioactive decay to electricity using thermocouples. RTGs have a long operating life, are reasonably lightweight, and require little or no maintenance once assembled and tested. These factors make RTGs particularly attractive for use in spacecraft. However, because RTGs contain significant quantities of radioactive materials, normally plutonium-238 and its decay products, they must be transported in packages built in accordance with Title 10, Code of Federal Regulations, Part 71. The U.S. Department of Energy assigned the Radioisotope Thermoelectric Generator Transportation System (RTGTS) Program to Westinghouse Hanford Company in 1988 to develop a system meeting the regulatory requirements. The program objective was to develop a transportation system that would fully comply with 10 CFR 71 while protecting RTGs from adverse environmental conditions during normal conditions of transport (e.g., shock and heat). The RTGTS is scheduled for completion in December 1996 and will be available to support the National Aeronautics and Space Administration{close_quote}s Cassini mission to Saturn in October 1997. This paper provides an overview of the RTGTS and discusses the hardware being produced. Additionally, various program management innovations mandated by recent major changes in the U.S. Department of Energy structure and resources will be outlined. {copyright} {ital 1996 American Institute of Physics.}

  20. Characterization of the Advanced Stirling Radioisotope Generator EU2

    NASA Technical Reports Server (NTRS)

    Lewandowski, Edward J.; Oriti, Salvatore M.; Schifer, Nicholas A.

    2015-01-01

    Significant progress was made developing the Advanced Stirling Radioisotope Generator (ASRG), a 140-watt radioisotope power system. While the ASRG flight development project has ended, the hardware that was designed and built under the project is continuing to be tested to support future Stirling-based power system development. NASA GRC recently completed the assembly of the ASRG Engineering Unit 2 (EU2). The ASRG EU2 consists of the first pair of Sunpower's ASC-E3 Stirling convertors mounted in an aluminum housing, and Lockheed Martin's Engineering Development Unit (EDU) 4 controller (a fourth generation controller). The ASC-E3 convertors and Generator Housing Assembly (GHA) closely match the intended ASRG Qualification Unit flight design. A series of tests were conducted to characterize the EU2, its controller, and the convertors in the flight-like GHA. The GHA contained an argon cover gas for these tests. The tests included: measurement of convertor, controller, and generator performance and efficiency, quantification of control authority of the controller, disturbance force measurement with varying piston phase and piston amplitude, and measurement of the effect of spacecraft DC bus voltage on EU2 performance. The results of these tests are discussed and summarized, providing a basic understanding of EU2 characteristics and the performance and capability of the EDU 4 controller.

  1. Characterization of the Advanced Stirling Radioisotope Generator Engineering Unit 2

    NASA Technical Reports Server (NTRS)

    Lewandowski, Edward J.; Oriti, Salvatore M.; Schifer, Niholas A.

    2016-01-01

    Significant progress was made developing the Advanced Stirling Radioisotope Generator (ASRG) 140-W radioisotope power system. While the ASRG flight development project has ended, the hardware that was designed and built under the project is continuing to be tested to support future Stirling-based power system development. NASA Glenn Research Center recently completed the assembly of the ASRG Engineering Unit 2 (EU2). The ASRG EU2 consists of the first pair of Sunpower's Advanced Stirling Convertor E3 (ASC-E3) Stirling convertors mounted in an aluminum housing, and Lockheed Martin's Engineering Development Unit (EDU) 4 controller (a fourth-generation controller). The ASC-E3 convertors and Generator Housing Assembly (GHA) closely match the intended ASRG Qualification Unit flight design. A series of tests were conducted to characterize the EU2, its controller, and the convertors in the flight-like GHA. The GHA contained an argon cover gas for these tests. The tests included measurement of convertor, controller, and generator performance and efficiency; quantification of control authority of the controller; disturbance force measurement with varying piston phase and piston amplitude; and measurement of the effect of spacecraft direct current (DC) bus voltage on EU2 performance. The results of these tests are discussed and summarized, providing a basic understanding of EU2 characteristics and the performance and capability of the EDU 4 controller.

  2. [The successful prolongation of a twin preterm pregnancy complicated by a dead fetus and disseminated intravascular coagulation].

    PubMed

    Hasbún, J; Muñoz, H; von Mühlenbrock, R; Pommer, R; Fardella, P; Yuri, C

    1992-01-01

    A clinical case of twin pregnancy with one in utero death fetus, at 24 weeks of gestation is presented, accompanied by disseminated intravascular coagulation. The successful treatment with heparin its described.

  3. Optimizing methods for the study of intravascular lipid metabolism in zebrafish.

    PubMed

    Chen, Kan; Wang, Chang-Qian; Fan, Yu-Qi; Xie, Yu-Shui; Yin, Zhao-Fang; Xu, Zuo-Jun; Zhang, Hui-Li; Cao, Jia-Tian; Han, Zhi-Hua; Wang, Yue; Song, Dong-Qiang

    2015-03-01

    The zebrafish (Danio rerio) is a useful vertebrate model for use in cardiovascular drug discovery. The present study aimed to construct optimized methods for the study of intravascular lipid metabolism of zebrafish. The lipophilic dye, Oil Red O, was used to stain fasting zebrafish one to eight days post-fertilization (dpf) and to stain 7-dpf zebrafish incubated in a breeding system containing 0.1% egg yolk as a high-fat diet (HFD) for 48 h. Three-dpf zebrafish were kept in CholEsteryl boron-dipyrromethene (BODIPY) 542/563 C11 water for 24 h which indicated the efficiency of CholEsteryl BODIPY 542/563 C11 intravascular cholesterol staining. Subsequently, 7-dpf zebrafish were incubated in water containing the fluorescent probe CholEsteryl BODIPY 542/563 C11 and fed a high-cholesterol diet (HCD) for 10 d. Two groups of 7-dpf zebrafish were incubated in regular breeding water and fed with a regular or HCD containing CholEsteryl BODIPY 542/563 C11 for 10 d. Finally, blood lipids of adult zebrafish fed with regular or HFD for seven weeks were measured. Oil Red O was not detected in the blood vessels of 7-8-dpf zebrafish. Increased intravascular lipid levels were detected in 7-dpf zebrafish incubated in 0.1% egg yolk, indicated by Oil Red O staining. Intravascular cholesterol was efficiently stained in 3-dpf zebrafish incubated in breeding water containing CholEsteryl BODIPY 542/563 C11; however, this method was inappropriate for the calculation of intravascular fluorescence intensity in zebrafish >7‑dpf. In spite of this, intra-aortic fluorescence intensity of zebrafish fed a HCD containing CholEsteryl BODIPY 542/563 C11 was significantly higher (P<0.05) than that of those fed a regular diet containing CholEsteryl BODIPY 542/563 C11. The serum total cholesterol and triglyceride levels of adult zebrafish fed a HFD were markedly increased compared to those of the control group (P<0.05). In conclusion, the use of Oil Red O staining and CholEsteryl BODIPY 542/563 C11 may

  4. Radio-isotope production scale-up at the University of Wisconsin

    SciTech Connect

    Nickles, Robert Jerome

    2014-06-19

    Our intent has been to scale up our production capacity for a subset of the NSAC-I list of radioisotopes in jeopardy, so as to make a significant impact on the projected national needs for Cu-64, Zr-89, Y-86, Ga-66, Br-76, I-124 and other radioisotopes that offer promise as PET synthons. The work-flow and milestones in this project have been compressed into a single year (Aug 1, 2012- July 31, 2013). The grant budget was virtually dominated by the purchase of a pair of dual-mini-cells that have made the scale-up possible, now permitting the Curie-level processing of Cu-64 and Zr-89 with greatly reduced radiation exposure. Mile stones: 1. We doubled our production of Cu-64 and Zr-89 during the grant period, both for local use and out-bound distribution to ≈ 30 labs nationwide. This involved the dove-tailing of beam schedules of both our PETtrace and legacy RDS cyclotron. 2. Implemented improved chemical separation of Zr-89, Ga-66, Y-86 and Sc-44, with remote, semi-automated dissolution, trap-and-release separation under LabView control in the two dual-mini-cells provided by this DOE grant. A key advance was to fit the chemical stream with miniature radiation detectors to confirm the transfer operations. 3. Implemented improved shipping of radioisotopes (Cu-64, Zr-89, Tc-95m, and Ho-163) with approved DOT 7A boxes, with a much-improved FedEx shipping success compared to our previous steel drums. 4. Implemented broad range quantitative trace metal analysis, employing a new microwave plasma atomic emission spectrometer (Agilent 4200) capable of ppb sensitivity across the periodic table. This new instrument will prove essential in bringing our radiometals into FDA compliance needing CoA’s for translational research in clinical trials. 5. Expanded our capabilities in target fabrication, with the purchase of a programmable 1600 oC inert gas tube furnace for the smelting of binary alloy target materials. A similar effort makes use of our RF induction furnace, allowing

  5. Space radioisotope power source requirements update and technology status

    SciTech Connect

    Mondt, J.F.

    1998-07-01

    The requirements for a space advanced radioisotope power source are based on potential deep space missions being investigated for the NASA Advanced Space Systems Development Program. Since deep space missions have not been approved, updating requirements is a continuos parallel process of designing the spacecraft and the science instruments to accomplish the potential missions and developing the power source technology to meet changing requirements. There are at least two potential missions, Pluto/Kuiper Express and Europa Orbiter, which may require space advanced radioisotope power sources. The Europa Orbiter has been selected as the preferred first potential mission. However the final decision will depend on the technology readiness of all the subsystems and the project must be able to switch to Pluto Kuiper Express as the first mission as late as the beginning of fiscal year 2000. Therefore the requirements for the power source will cover both potential missions. As the deep space spacecraft design evolves to meet the science requirements and the Alkali Metal Thermal to Electric (AMTEC) technology matures the advanced radioisotope power source design requirements are updated The AMTEC technology developed to date uses stainless steel for the sodium containment material. The higher efficiency required for the space power system dictates that the AMTEC technology must operate at a higher temperature than possible with stainless steel. Therefore refractory materials have been selected as the baseline material for the AMTEC cell. These refractory materials are Nb1Zr for the hot side and Nb1Zr or Nb10Hf1Ti for the cold side. These materials were selected so the AMTEC cell can operate at 1150K to 1350K hot side temperature and 600K to 700K cold side temperature and meet the present power and mass requirements using four to six general purpose heat source modules as the heat source. The new containment materials and brazes will be evaluated as to lifetime

  6. [Intravascular biocompatibility of decellularized xenogenic vascular scaffolds/PHBHHx hybrid material for cardiovascular tissue engineering].

    PubMed

    Wu, Song; Liu, Yinglong; Cui, Bin; Tang, Yue; Wang, Qiang; Qu, Xianghua; Chen, Guoqiang

    2008-04-01

    Poly (3-hydroxybutyrate-co-3-hydroxyhexanoate, PHBHHx) has superior mechanical and biocompatibility that may enable it to meet cardiovascular tissue engineering applications. We developed hybrid materials based on decellularized xenogenic vascular scaffolds that were coated with PHBHHx to investigate the intravascular biocompatibility. The hybrid patches were implanted in the rabbit abdominal aorta (hybrid patch, n = 12). Only decellularized xenogenic vascular scaffolds were implanted without coating as control (uncoated patch, n = 12). The patches were explanted and examined histologically, and biochemically at 1, 4 and 12 weeks after the surgery. The hybrid patches maintained original shapes, covered by confluent layer of cells and had less calcification than uncoated control. The results indicated that PHBHHx coating reduced calcification, promoted the repopulation of hybrid patch with recipients cells. In conclusion, PHBHHx showed remarkable intravascular biocompatibility and would benefit endothelization which would be a useful candidate for lumen of cardiovascular tissue engineering. PMID:18616171

  7. An Arthrobacter spp. bacteremia leading to fetal death and maternal disseminated intravascular coagulation.

    PubMed

    Shigeta, Naoya; Ozaki, Kimiaki; Hori, Kensuke; Ito, Kimihiko; Nakayama, Masahiro; Nakahira, Kumiko; Yanagihara, Itaru

    2013-02-01

    A 34-year-old parous woman developed high fever and threatened preterm labor after a 1-day trip, for which she was receiving prenatal care at a hospital. Three days after onset, at 24 4/7 weeks of gestation, she was transferred to our hospital in an emergency. Soon after the woman's arrival at our hospital, the infant was spontaneously stillborn via a transvaginal delivery. Laboratory tests revealed severe maternal disseminated intravascular coagulation with renal and liver insufficiency. Histopathologic examination of the placenta revealed vast fibrin deposition and remarkable neutrophilic infiltration in the intervillous space, suggesting a rare bacterial infection caused by Arthrobacter spp. The bacteria were predominantly detected in the placenta and maternal blood serum by common bacterial 16S rRNA sequencing after polymerase chain reaction amplification. We report the first case, to our knowledge, of bacteremia with Arthrobacter spp., which may lead to maternal disseminated intravascular coagulation and intrauterine fetal death.

  8. Intravascular photoacoustic imaging of exogenously labeled atherosclerotic plaque through luminal blood

    PubMed Central

    Yeager, Doug; Karpiouk, Andrei; Wang, Bo; Amirian, James; Sokolov, Konstantin; Smalling, Richard

    2012-01-01

    Abstract. Combined intravascular ultrasound and intravascular photoacoustic (IVUS/IVPA) imaging has been previously established as a viable means for assessing atherosclerotic plaque morphological and compositional characteristics using both endogenous and exogenous contrast. In this study, IVUS/IVPA imaging of atherosclerotic rabbit aortas following systemic injection of gold nanorods (AUNRs) with peak absorbance within the tissue optical window is performed. Ex vivo imaging results reveal a high photoacoustic signal from localized AUNRs in regions with atherosclerotic plaques. Corresponding histological staining further confirms the preferential extravasation of AUNRs in atherosclerotic regions with compromised luminal endothelium and acute inflammation. The ability to detect AUNRs using combined IVUS and photoacoustic imaging in the presence of luminal saline and luminal blood is evaluated using both spectroscopic and single wavelength IVPA imaging techniques. Results demonstrate that AUNR detection within the arterial wall can be achieved using both methods, even in the case of imaging through luminal blood. PMID:23224013

  9. Enhanced glucose tolerance by intravascularly administered piceatannol in freely moving healthy rats.

    PubMed

    Oritani, Yukihiro; Okitsu, Teru; Nishimura, Eisaku; Sai, Masahiko; Ito, Tatsuhiko; Takeuchi, Shoji

    2016-02-12

    Piceatannol is a phytochemical in the seeds of passion fruit that has a hypoglycemic effect when orally administered. To elucidate the contribution of intact and metabolites of piceatannol after gastro-intestinal absorption to hypoglycemic effect, we examined the influence of piceatannol and isorhapontigenin on blood glucose concentrations during fasting and glucose tolerance tests by administering them intravascularly to freely moving healthy rats. We found that intravascularly administered piceatannol reduced the blood glucose concentrations during both fasting and glucose tolerance tests, but isorhapontigenin did not during either of them. Furthermore, we found that piceatannol increased the insulinogenic index during glucose tolerance tests and that piceatannol had no influence on insulin sensitivity by performing hyperinsulinemic euglycemic clamping tests. These results suggest that piceatannol orally intaken may enhance glucose tolerance by the effect of intact piceatannol through enhanced early-phase secretion of insulin. Therefore, oral intake of piceatannol might contribute to proper control of postprandial glycemic excursions in healthy subjects.

  10. [Intravascular lymphoma treated with anti CD20 monoclonal antibodies. Report of one case].

    PubMed

    Alfaro, Jorge; Espinoza, Arturo; Manŕiquez, María; Moyano, Leonor; González, Néstor; Larrondo, Milton; Figueroa, Gastón

    2004-11-01

    We report a 78 year old male with prostatism, that was subjected to a prostate biopsy. The pathological study showed a microvascular lymphocytic infiltration. Four months later, the patients presented with reduced alertness, cough, dyspnea, fever and elevation of lactic dehydrogenase and erythrocyte sedimentation rate. Chest and abdominal CAT scans, bone marrow aspirate, protein electrophoresis and prostate specific antigen were normal. A re-evaluation of prostate biopsy showed an intravascular lymphoid infiltration, positive for CD45 and CD20, compatible with the diagnosis of intravascular lymphoma. Chemotherapy was started, but it was not tolerated by the patient and the response was partial. Therefore, treatment with monoclonal antibodies anti CD20 (Rituximab) was started. The tumor had a complete and prolonged (24 months) remission after the treatment

  11. Radioisotope thermoelectric generator/thin fragment impact test

    NASA Astrophysics Data System (ADS)

    Reimus, M. A. H.; Hinckley, J. E.

    1998-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of 238Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the converter housing, failure of one fueled clad, and release of a small quantity of fuel.

  12. End-on radioisotope thermoelectric generator impact tests

    NASA Astrophysics Data System (ADS)

    Reimus, M. A. H.; Hinckley, J. E.

    1997-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of 238Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). The modular GPHS design was developed to address both survivability during launch abort and return from orbit. The first two RTG Impact Tests were designed to provide information on the response of a fully loaded RTG to end-on impact against a concrete target. The results of these tests indicated that at impact velocities up to 57 m/s the converter shell and internal components protect the GPHS capsules from excessive deformation. At higher velocities, some of the internal components of the RTG interact with the GPHS capsules to cause excessive localized deformation and failure.

  13. Fabrication of light weight radioisotope heater unit hardware components

    NASA Astrophysics Data System (ADS)

    McNeil, Dennis C.

    1996-03-01

    The Light Weight Radioisotope Heater Unit (LWRHU) is planned to be used on the National Aeronautics and Space Administration (NASA) Cassini Mission, to provide localized thermal energy as strategic locations on the spacecraft. These one watt heater units will support the operation of many on-board instruments that require a specific temperature range to function properly. The system incorporates a fuel pellet encapsulated in a vented metallic clad fabricated from platinum-30% rhodium (Pt-30%Rh) tubing, sheet and foil materials. To complete the package, the clad assemblies are placed inside a combination of graphite components. This report describes the techniques employed by Mound related to the fabrication and sub assembly processes of the LWRHU clad hardware components. Included are details concerning configuration control systems, material procurement and certification, hardware fabrication specifics, and special processes that are utilized.

  14. Radioisotope thermoelectric generator/thin fragment impact test

    SciTech Connect

    Reimus, M.A.H.; Hinckley, J.E.

    1998-12-31

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the convertor housing, failure of one fueled clad, and release of a small quantity of fuel.

  15. End-on radioisotope thermoelectric generator impact tests

    SciTech Connect

    Reimus, M.A.H.; Hhinckley, J.E.

    1997-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of [sup 238]Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). The modular GPHS design was developed to address both survivability during launch abort and return from orbit. The first two RTG Impact Tests were designed to provide information on the response of a fully loaded RTG to end-on impact against a concrete target. The results of these tests indicated that at impact velocities up to 57 m/s the converter shell and internal components protect the GPHS capsules from excessive deformation. At higher velocities, some of the internal components of the RTG interact with the GPHS capsules to cause excessive localized deformation and failure.

  16. Reliability Demonstration Approach for Advanced Stirling Radioisotope Generator

    NASA Technical Reports Server (NTRS)

    Ha, CHuong; Zampino, Edward; Penswick, Barry; Spronz, Michael

    2010-01-01

    Developed for future space missions as a high-efficiency power system, the Advanced Stirling Radioisotope Generator (ASRG) has a design life requirement of 14 yr in space following a potential storage of 3 yr after fueling. In general, the demonstration of long-life dynamic systems remains difficult in part due to the perception that the wearout of moving parts cannot be minimized, and associated failures are unpredictable. This paper shows a combination of systematic analytical methods, extensive experience gained from technology development, and well-planned tests can be used to ensure a high level reliability of ASRG. With this approach, all potential risks from each life phase of the system are evaluated and the mitigation adequately addressed. This paper also provides a summary of important test results obtained to date for ASRG and the planned effort for system-level extended operation.

  17. Forms of vitamin B12 in radioisotope dilution assays.

    PubMed Central

    Begley, J A; Hall, C A

    1981-01-01

    Since the presence of analogues of vitamin B12 (B12, cobalamin, Cbl) has been postulated as the basis for the high values obtained by some radioisotope dilution assays (RIDA) of serum Cbl we examined serum for analogues. None could be demonstrated in the extracts of serum prepared for RIDA as sought by both direct and indirect techniques. The natural forms of serum Cbl were converted to cyanocobalamin (CN Cbl) by this process of extraction which included cyanide (CN). The correctly performed RIDA for Cbl based on R binder gave higher values than a RIDA based on intrinsic factor or than by bioassay. By exclusion, the difference appeared to be due to unidentified factors rather than the presence of analogues. Images PMID:7019262

  18. AMTEC radioisotope power system for the Pluto Express mission

    SciTech Connect

    Ivanenok, J.F. III; Sievers, R.K.

    1995-12-31

    The Alkali Metal Thermal to Electric Converter (AMTEC) technology has made substantial advances in the last 3 years through design improvements and technical innovations. In 1993 programs began to produce an AMTEC cell specifically for the NASA Pluto Express Mission. A set of efficiency goals was established for this series of cells to be developed. According to this plan, cell {number_sign}8 would be 17% efficient but was actually 18% efficient. Achieving this goal, as well as design advances that allow the cell to be compact, has resulted in pushing the cell from an unexciting 2 W/kg and 2% efficiency to very attractive 40 W/kg and 18% measured efficiency. This paper will describe the design and predict the performance of a radioisotope powered AMTEC system for the Pluto Express mission.

  19. RTGs - The powering of Ulysses. [Radio-isotope Thermoelectric Generator

    NASA Technical Reports Server (NTRS)

    Mastal, E. F.; Campbell, R. W.

    1990-01-01

    The radio-isotope thermoelectric generator (RTG) for Ulysses' electronic supply is described noting that lack of sufficient sunlight renders usual solar cell power generation ineffective due to increased distance from sun. The history of the RTG in the U.S.A. is reviewed citing the first RTG launch in 1961 with an electrical output of 2.7 W and the improved Ulysses RTG, which provides 285 W at mission beginning and 250 W at mission end. The RTG concept is discussed including the most recent RTG technology developed by the DOE, the General Purpose Heat Source RTG (GPHS-RTG). The system relies upon heat generated by radioactive decay using radioactive plutonium-238, which is converted directly to energy using the Seebeck method.

  20. Development and Buildup of a Stirling Radioisotope Generator Electrical Simulator

    NASA Technical Reports Server (NTRS)

    Prokop, Norman F.; Krasowski, Michael J.; Greer, Lawrence C.; Flatico, Joseph M.; Spina, Dan C.

    2008-01-01

    This paper describes the development of a Stirling Radioisotope Generator (SRG) Simulator for use in a prototype lunar robotic rover. The SRG developed at NASA Glenn Research Center (GRC) is a promising power source for the robotic exploration of the sunless areas of the moon. The simulator designed provides a power output similar to the SRG output of 5.7 A at 28 Vdc, while using ac wall power as the input power source. The designed electrical simulator provides rover developers the physical and electrical constraints of the SRG supporting parallel development of the SRG and rover. Parallel development allows the rover design team to embrace the SRG s unique constraints while development of the SRG is continued to a flight qualified version.

  1. Radioisotope thermoelectric generator/thin fragment impact test

    SciTech Connect

    Reimus, M. A. H.; Hinckley, J. E.

    1998-01-15

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the converter housing, failure of one fueled clad, and release of a small quantity of fuel.

  2. Radioisotope thermoelectric generator/thin fragment impact test

    SciTech Connect

    Reimus, M.A.; Hinckley, J.E.

    1998-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the converter housing, failure of one fueled clad, and release of a small quantity of fuel. {copyright} {ital 1998 American Institute of Physics.}

  3. End-on radioisotope thermoelectric generator impact tests

    SciTech Connect

    Reimus, M.A.; Hinckley, J.E.

    1997-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). The modular GPHS design was developed to address both survivability during launch abort and return from orbit. The first two RTG Impact Tests were designed to provide information on the response of a fully loaded RTG to end-on impact against a concrete target. The results of these tests indicated that at impact velocities up to 57 m/s the converter shell and internal components protect the GPHS capsules from excessive deformation. At higher velocities, some of the internal components of the RTG interact with the GPHS capsules to cause excessive localized deformation and failure. {copyright} {ital 1997 American Institute of Physics.}

  4. Testing to Characterize the Advanced Stirling Radioisotope Generator Engineering Unit

    NASA Technical Reports Server (NTRS)

    Lewandowski, Edward; Schreiber, Jeffrey

    2010-01-01

    The Advanced Stirling Radioisotope Generator (ASRG), a high efficiency generator, is being considered for space missions. Lockheed Martin designed and fabricated an engineering unit (EU), the ASRG EU, under contract to the Department of Energy. This unit is currently undergoing extended operation testing at the NASA Glenn Research Center to generate performance data and validate life and reliability predictions for the generator and the Stirling convertors. It has also undergone performance tests to characterize generator operation while varying control parameters and system inputs. This paper summarizes and explains test results in the context of designing operating strategies for the generator during a space mission and notes expected differences between the EU performance and future generators.

  5. .sup.82 Sr-.sup.82 Rb Radioisotope generator

    DOEpatents

    Grant, Patrick M.; Erdal, Bruce R.; O'Brien, Harold A.

    1976-01-01

    An improved .sup.82 Sr-.sup.82 Rb radioisotope generator system, based upon the complexing ion exchange resin Chelex-100, has been developed. Columns of this material can be easily and rapidly milked, and the Rb-Sr separation factor for a fresh generator was found to be > 10.sup.7. Approximately 80 percent of the .sup.82 Rb present was delivered in a 15-ml volume of aqueous 0.2 M NH.sub.4 Cl solution. After more than 6 liters of eluant had been put through the generator, the Rb-Sr separation factor was still observed to be > 10.sup.5, and no unusual strontium breakthrough behavior was seen in the system over nearly three .sup.82 Sr half lives.

  6. Multimodality Therapy: Bone-Targeted Radioisotope Therapy of Prostate Cancer

    PubMed Central

    Tu, Shi-Ming; Lin, Sue-Hwa; Podoloff, Donald A.; Logothetis, Christopher J.

    2016-01-01

    Accumulating data suggest that bone-seeking radiopharmaceuticals can be used to treat prostate cancer bone metastasis and improve the clinical outcome of patients with advanced prostate cancer. It remains to be elucidated whether radiopharmaceuticals enhance the disruption of the onco-niche or the eradication of micrometastatic cells in the bone marrow. The purpose of this review is to investigate the role of bone-targeted radioisotope therapy in the setting of multimodality therapy for advanced prostate cancer. We examine available data and evaluate whether dose escalation, newer generations, or repeated dosing of radiopharmaceuticals enhance their antitumor effects and whether their combination with hormone ablative therapy, chemotherapy, or novel targeted therapy can improve clinical efficacy. PMID:20551894

  7. Intravascular ATP and the regulation of blood flow and oxygen delivery in humans.

    PubMed

    Crecelius, Anne R; Kirby, Brett S; Dinenno, Frank A

    2015-01-01

    Regulation of vascular tone is a complex response that integrates multiple signals that allow for blood flow and oxygen supply to match oxygen demand appropriately. Here, we discuss the potential role of intravascular adenosine triphosphate (ATP) as a primary factor in these responses and put forth the hypothesis that deficient ATP release contributes to impairments in vascular control exhibited in aged and diseased populations. PMID:25390296

  8. Study of restenosis in drug eluting stents: new insights from greyscale intravascular ultrasound and virtual histology.

    PubMed

    Garcia-Garcia, Hector M; Shen, Zhujun; Piazza, Nicolo

    2009-05-01

    In current cardiology practice, many patients undergo secondary revascularisation due to reduced long-term vein graft patency or in-stent restenosis. In this report, we describe causes of drug-eluting stent restenosis identifiable by intravascular ultrasound imaging (IVUS) and variables related to restenosis used for reporting greyscale IVUS. In addition, IVUS findings in bypass grafts and the long-term results after stent implantation are provided. Finally, the usefulness of IVUS virtual histology for the study of restenosis is described.

  9. Laparoscopic Manipulation of a Probe-based Confocal Laser Endomicroscope Using a Steerable Intravascular Catheter

    PubMed Central

    Desjardins, Adrien E.; Gurusamy, Kurinchi; Hawkes, David J.; Davidson, Brian R.

    2015-01-01

    Probe-based confocal laser endomicroscopy is an emerging imaging modality that enables visualization of histologic details during endoscopy and surgery. A method of guiding the probe with millimeter accuracy is required to enable imaging in all regions of the abdomen accessed during laparoscopy. On the basis of a porcine model of laparoscopic liver resection, we report our experience of using a steerable intravascular catheter to guide a probe-based confocal laser endomicroscope. PMID:25807277

  10. Surgical management of Wilms tumor with intravascular extension: a single-institution experience.

    PubMed

    Aspiazu, Diego; Fernandez-Pineda, Israel; Cabello, Rosa; Ramirez, Gema; Alvarez-Madrid, Antonio; De Agustin, Juan Carlos

    2012-02-01

    The purpose of this study was to retrospectively analyze the clinical presentation, treatment, and outcomes of children with Wilms tumor (WT) and intravascular extension who were treated at a single institution. A retrospective review was conducted of medical records of all children with Wilms tumor and intravascular extension treated at Virgen del Rocio Children's Hospital between 1992 and 2010. Seven patients (median age 3.4 years, range 2-8.1 years) were identified. At diagnosis, 6 of the 7 patients (85.7%) presented with tumor thrombus that reached the right atrium (RA) and 1 patient with infrahepatic inferior vena cava (IVC) thrombus. All patients received neoadjuvant chemotherapy (SIOP 2001 protocol) with vincristine, doxorubicin, and actinomycin D. Regression of the intravascular extension of the tumor was documented in all patients. Postchemotherapy level of extension was suprahepatic IVC in 1 patient, infrahepatic IVC in 2 patients, renal vein (RV) in 1 patient, and RA in 3 patients. Nephrectomy and thrombectomy were performed in all cases, requiring cardiopulmonary bypass for the 4 patients who presented with suprahepatic IVC and RA thrombus. The other 3 patients with infrahepatic IVC and RV involvement underwent cavotomy and thrombus extraction. Computed tomography, ultrasonography, and echocardiography were used for diagnosis and follow-up. All patients remain disease-free with a median follow-up of 6.3 years (range, 2-19 years). Neoadjuvant chemotherapy for WT with intravascular extension may facilitate the resection by decreasing the extent of the tumor thrombus. Cardiopulmonary bypass is indicated for suprahepatic IVC and RA involvement. Accurate diagnostic imaging is necessary.

  11. Recurrent thrombotic occlusions of arteries and veins caused by intravascular metastatic adenocarcinoma.

    PubMed Central

    Levi, M; Bronkhorst, C; Noorduyn, L A; Vreeken, J

    1994-01-01

    The occurrence of unexplained, rapidly recurring occlusions of arteries and veins in a previously healthy young woman is described. Post mortem examination showed no macroscopic abnormalities but revealed microscopic metastatic adenocarcinoma with remarkable intravascular localisation of the malignant cells. Whereas highly sensitive markers for the existence of systemic activation of blood coagulation remained within the normal range, it is suggested that specific characteristics of the tumour cells may have been responsible for this particular clinical presentation. PMID:7962660

  12. Effect of intravascular irradiation of He-Ne laser on cerebral infarction: Hemorrheology and apoptosis

    NASA Astrophysics Data System (ADS)

    Zhu, Jian; Liang, Min-yi; Cao, Hao-cai; Li, Xiao-Yuan; Li, Shao-ming; Li, Shun-hao; Li, Wen-qi; Zhang, Jin-hong; Liu, Lei; Lai, Jian-hong

    2005-07-01

    Objective: To explore the efficacy of He-Ne laser intravascular irradiation on infarction and hemorrheology. To observe the effects of intravascular low level He-Ne laser irradiation (ILLLI) of blood on cell proliferation, apoptosis and chromosome in lymphocyte from cerebral infarction Methods: Seventy cases with cerebral infarction were randomly divided into groups control group (35 cases) treated only with common drugs and therapeutic group (35 cases) treated besides common drugs also by He-Ne laser intravascular irradiation. Their hemorrheology index and treatment results were observed and compared. The blood lymphocytes of cerebral infarction were cultured before and after treatment. After that, the mitosis index (MI), cell kinetics index (CKI), sister-chromatid exchanges (SCE) frequencies and apoptosis were determined. Results The therapeutic group was better than the control one. The effective rate in the therapeutic group was 88.6%, in the control one was 65.7%. The viscosity and fibrinogen, etc were better than that in the control group with significant difference (P<0.01). The lymphocyte proliferation index was significantly two increased than the control one (P>0.05) in cerebral infarction patients after treatment; The CKI of lymphocytes had no obvious difference among groups (P>0.05) SCE frequencies of lymphocytes had no statistic significance between control group and ILLLI on (P>0.05). It showed the apoptosis rate of lymphocytes in cerebral infarction patients after ILLLI treatment increased significantly compared with the control group, (P<0.001). There was a significant difference of apoptosis rate of lymphocytes in cerebral infarction patients than the control (P<0.001). Conclusions: During the He-Ne laser intravascular irradiation of the cerebral infarction, the low level He-Ne by ILLLI can increase the proliferation of lymphocytes, and can induce lymphocytes to apoptosis, but has no mutagenicity of cells.

  13. [Evaluation of the severity course and prognosis of disseminated intravascular blood coagulation syndrome].

    PubMed

    Kinakh, M V; Chaplyk, V V; Fedchyshyn, N R

    2009-01-01

    Activation of the peroxidal oxidation of lipids (POL) processes with its primary and secondary products levels raising constitutes a favourable sign, according to data of examination of 66 patients, suffering different phases of disseminated intravascular blood coagulation syndrome (DIBCS). The POL products contents reduction (areactive course) characterizes the process severity and constitutes an unfavourable prognostical sign. The areactive course rate is the highest in the patients, suffering DIBCS, phase III.

  14. Isolated Intravascular Large B-cell Lymphoma Presenting with Diffuse Ground Glass Pulmonary Infiltrates.

    PubMed

    Srivali, Narat; Pannu, Bibek S; Iyer, Vivek N

    2016-06-01

    A case of 44-year-old man with dyspnea and CT chest demonstrated bilateral infiltration. Patient was failed to improve with antibiotics and steroid. Finally, video-assisted thoracic surgery-guided lung biopsy was performed and surprisingly revealed intravascular large B cell lymphoma. The patient was subsequently started on chemotherapy with considerable clinical improvement. At the time of last follow-up (4 years from diagnosis); there was no clinical or radiologic evidence of tumor recurrence. PMID:27408440

  15. Advanced Stirling Convertor Development for NASA Radioisotope Power Systems

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.; Wilson, Scott D.; Collins, Josh

    2015-01-01

    Sunpower Inc.'s Advanced Stirling Convertor (ASC) initiated development under contract to the NASA Glenn Research Center and after a series of successful demonstrations, the ASC began transitioning from a technology development project to a flight development project. The ASC has very high power conversion efficiency making it attractive for future Radioisotope Power Systems (RPS) in order to make best use of the low plutonium-238 fuel inventory in the United States. In recent years, the ASC became part of the NASA and Department of Energy (DOE) Advanced Stirling Radioisotope Generator (ASRG) Integrated Project. Sunpower held two parallel contracts to produce ASCs, one with the DOE and Lockheed Martin to produce the ASC-F flight convertors, and one with NASA Glenn for the production of ASC-E3 engineering units, the initial units of which served as production pathfinders. The integrated ASC technical team successfully overcame various technical challenges that led to the completion and delivery of the first two pairs of flightlike ASC-E3 by 2013. However, in late fall 2013, the DOE initiated termination of the Lockheed Martin ASRG flight development contract driven primarily by budget constraints. NASA continues to recognize the importance of high-efficiency ASC power conversion for RPS and continues investment in the technology including the continuation of ASC-E3 production at Sunpower and the assembly of the ASRG Engineering Unit #2. This paper provides a summary of ASC technical accomplishments, overview of tests at Glenn, plans for continued ASC production at Sunpower, and status of Stirling technology development.

  16. Radioisotope synoviorthesis with Holmium-166-chitosan complex in haemophilic arthropathy.

    PubMed

    Cho, Y J; Kim, K I; Chun, Y S; Rhyu, K H; Kwon, B K; Kim, D Y; Yoo, M C

    2010-07-01

    Radiosynoviorthesis is a safe and easy method for synovectomy in haemophilic arthropathy. Various agents have been used in radiosynoviorthesis, especially newly developed agent Holmium-166-chitosan complex has good clinical outcome. This study analysed clinical results and radiologic evaluation of radioisotope synoviorthesis using Holmium-166-chitosan complex in haemophilic arthropathy. From March 2001 to December 2003, 58 radiosynoviorthesis were performed in 53 haemophiliacs. The average age at procedure was 13.8 years. The Arnold and Hilgartner stage of the patients was from I to IV. Holmium-166-chitosan complex was injected in 31 ankle joints, 19 elbow joints and 8 knee joints. Average follow-up was 33 months since primary procedure. The range of motion of each joint, frequency of intra-articular bleeding and factor dose used were analysed for clinical assessment. There was no significant improvement of range of motion in affected joints. After procedure, the average frequency of bleeding of the elbow joint has decreased from 3.76 to 0.47 times per month, the knee joint from 5.87 to 1.12 times per month, and the ankle joint from 3.62 to 0.73 times per month respectively (P < 0.05). After treatment, the average coagulation factor dose injected was significantly decreased to 779.3 units per month from 2814.8 units per month before treatment (P < 0.001). Radioisotope synoviorthesis with Holmium-166-chitosan complex in haemophilic arthropathy is a very safe and simple procedure with the expectation of a satisfactory outcome without serious complication. It has excellent bleeding control effect on target joint and the need for substitution of coagulation factor concentrate can be reduced.

  17. A high power, Coated Particle Fuel Compact Radioisotope Heat Unit

    NASA Astrophysics Data System (ADS)

    King, Jeffrey C.; El-Genk, Mohamed S.

    2001-02-01

    A Coated Particle Fuel Compact, Radioisotope Heater Unit (CPFC-RHU) is proposed, which is capable of generating thermal power in excess of 27 W. This power output is more than four times that of a Hexa-RHU, which generates only six watts of thermal power. The design of the CPFC-RHU is identical to that of the Hexa-RHU, except that the six Pt-30Rh clad fuel pellets and the POCO graphite support in the latter are replaced with single-sized, ZrC coated, 238PuO2 fuel particles ~500 μm in diameter. In addition to fully retaining the helium gas generated by the radioactive decay of the fuel, the CPFC offers promise for enhanced safety. Thermal analyses of the CPFC-RHU show that while the Hexa-RHU is suitable for use in a radioisotope power system (RPS) operating at a converter hot-side temperature of 473 K, the CPFC-RHU could also be used at higher temperatures of 773 K and 973 K with a thermal efficiency >60%. Even at a 473 K converter hot-side temperature, the CPFC-RHU offers higher thermal efficiency (>90%) than the Hexa-RHU (~75%). The CPFC-RHU final design provides constant temperature, with almost uniform radial heat flux to the converter, for enhanced performance, better integration, and higher overall efficiency of the RPS. The present CPFC-RHU fills a gap in the power needs for future space missions requiring electric power of 1-15 W, from a single RPS. .

  18. Phosphorus-32 in the Phage Group: radioisotopes as historical tracers of molecular biology.

    PubMed

    Creager, Angela N H

    2009-03-01

    The recent historiography of molecular biology features key technologies, instruments and materials, which offer a different view of the field and its turning points than preceding intellectual and institutional histories. Radioisotopes, in this vein, became essential tools in postwar life science research, including molecular biology, and are here analyzed through their use in experiments on bacteriophage. Isotopes were especially well suited for studying the dynamics of chemical transformation over time, through metabolic pathways or life cycles. Scientists labeled phage with phosphorus-32 in order to trace the transfer of genetic material between parent and progeny in virus reproduction. Initial studies of this type did not resolve the mechanism of generational transfer but unexpectedly gave rise to a new style of molecular radiobiology based on the inactivation of phage by the radioactive decay of incorporated phosphorus-32. These 'suicide experiments', a preoccupation of phage researchers in the mid-1950s, reveal how molecular biologists interacted with the traditions and practices of radiation geneticists as well as those of biochemists as they were seeking to demarcate a new field. The routine use of radiolabels to visualize nucleic acids emerged as an enduring feature of molecular biological experimentation. PMID:19268872

  19. Analysis of the inadvertent reentry of the Cassini Spacecraft's Radioisotope Thermoelectric Generators

    NASA Astrophysics Data System (ADS)

    Daywitt, James E.; Bhutta, Bilal A.; Vacek, Daniel J.; Letts, William R.; Tobery, E. Wayne

    1999-01-01

    A rigorous multi-discipline approach has been developed to compute the aero/thermal/structural response of the Cassini Spacecraft's G_eneral P_urpose H_eat S_ource (GPHS) modules in the unlikely event of accidental reentry of the spacecraft during its Earth gravity-assist maneuver. A new r_eacting, a_blating, c_hemical e_quilibrium/nonequilibrium with r_adiation (RACER) full Navier-Stokes code is applied, along with an in-depth, transient-heating code, a nonlinear structural analysis code, and a six-degree-of-freedom flight-dynamics code. Attention is focused on the GPHS modules that would breakaway from the R_adioisotope T_hermoelectric G_enerators (RTGs) at high altitude. In addition, detailed analyses are performed to determine the survival/failure of the Graphite Impact Shells that would be released if the GPHS fails. The reentry velocity of the GPHS module (20 km/sec) is higher than any previously analyzed Earth reentry trajectory.

  20. Phosphorus-32 in the Phage Group: radioisotopes as historical tracers of molecular biology

    PubMed Central

    Creager, Angela N.H.

    2009-01-01

    The recent historiography of molecular biology features key technologies, instruments and materials, which offer a different view of the field and its turning points than preceding intellectual and institutional histories. Radioisotopes, in this vein, became essential tools in postwar life science research, including molecular biology, and are here analyzed through their use in experiments on bacteriophage. Isotopes were especially well suited for studying the dynamics of chemical transformation over time, through metabolic pathways or life cycles. Scientists labeled phage with phosphorus-32 in order to trace the transfer of genetic material between parent and progeny in virus reproduction. Initial studies of this type did not resolve the mechanism of generational transfer but unexpectedly gave rise to a new style of molecular radiobiology based on the inactivation of phage by the radioactive decay of incorporated phosphorus-32. These ‘suicide experiments’, a preoccupation of phage researchers in the mid-1950s, reveal how molecular biologists interacted with the traditions and practices of radiation geneticists as well as those of biochemists as they were seeking to demarcate a new field. The routine use of radiolabels to visualize nucleic acids emerged as an enduring feature of molecular biological experimentation. PMID:19268872

  1. Lead-free intravascular ultrasound transducer using BZT-50BCT ceramics.

    PubMed

    Yan, Xingwei; Lam, Kwok Ho; Li, Xiang; Chen, Ruimin; Ren, Wei; Ren, Xiaobing; Zhou, Qifa; Shung, K Kirk

    2013-06-01

    This paper reports the fabrication and evaluation of a high-frequency ultrasonic transducer based on a new lead-free piezoelectric material for intravascular imaging application. Lead-free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO4(BZT-50BCT) ceramic with a high dielectric constant (~2800) was employed to develop a high-frequency (~30 MHz) needle-type ultrasonic transducer. With superior piezoelectric performance (piezoelectric coefficient d33 ~ 600 pC/N), the lead-free transducer was found to exhibit a -6-dB bandwidth of 53% with an insertion loss of 18.7 dB. In vitro intravascular ultrasound (IVUS) imaging of a human cadaver coronary artery was performed to demonstrate the potential of the lead-free transducer for biomedical imaging applications. This is the first time that a lead-free transducer has been used for IVUS imaging application. The experimental results suggest that the BZT-50BCT ceramic is a promising lead-free piezoelectric material for high-frequency intravascular imaging applications.

  2. Lead-Free Intravascular Ultrasound Transducer Using BZT-50BCT Ceramics

    PubMed Central

    Yan, Xingwei; Lam, Kwok Ho; Li, Xiang; Chen, Ruimin; Ren, Wei; Ren, Xiaobing; Zhou, Qifa; Shung, K. Kirk

    2013-01-01

    This paper reports the fabrication and evaluation of a high-frequency ultrasonic transducer based on a new lead-free piezoelectric material for intravascular imaging application. Lead-free 0.5Ba(Zr0.2Ti0.8)O3−0.5(Ba0.7Ca0.3)TiO3 (BZT-50BCT) ceramic with a high dielectric constant (~2800) was employed to develop a high-frequency (~30 MHz) needle-type ultrasonic transducer. With superior piezoelectric performance (piezoelectric coefficient d33 ~ 600 pC/N), the lead-free transducer was found to exhibit a −6-dB bandwidth of 53% with an insertion loss of 18.7 dB. In vitro intravascular ultrasound (IVUS) imaging of a human cadaver coronary artery was performed to demonstrate the potential of the lead-free transducer for biomedical imaging applications. This is the first time that a lead-free transducer has been used for IVUS imaging application. The experimental results suggest that the BZT-50BCT ceramic is a promising lead-free piezoelectric material for high-frequency intravascular imaging applications. PMID:25004492

  3. The intravascular low level laser irradiation (ILLLI) in treatment of psoriasis clinically

    NASA Astrophysics Data System (ADS)

    Zhu, Jing; Nie, Fan; Shi, Hong-Min

    2005-07-01

    Objective: The title is research curative effect of intravascular low level laser irradiation (ILLLI) in treatment of psoriasis. Method: 478 patients with psoriasis from five groups to observe their efficacy. Group1 were treated by He-Ne laser combined with drug. Group 2 were treated by semi-conductor laser combined with drug. Group 3 were treated only by He-He laser. Group 4 were treated by semi-conductor laser. Group 5 were treated only by drug. The Ridit statistical analysis was applied to all of these data. The treatment of intravascular low level laser irradiation is as follow: laser power:4-5mw, 1 hour per day and 10 days as a period combined with vit C 2.0 g iv and inhalation of O2. Results: The clinical results: the near efficient rate was 100%, in group1-4, if combined with drugs it would be better. Ridit statistical analysis showed no significant difference between group1-4, p>0.05. The efficient rate 72.97% in group5.There were showed very significant difference with group1-4, p<0.01. 2.There were no significant differences between He-Ne laser (632.8nm) and semiconductor laser(650nm); 3.The efficacy of ILLLI in psoriasis was positive correlation to the ILLLI times. Conclusions: It can improve curative effect of intravascular low levellaser irradiation (ILLLI) in treatment of psoriasis.

  4. Stochastic bifurcation characteristics of SMA intravascular stent subjected to radial and axial excitations.

    PubMed

    Zhu, Zhiwen; Zhang, Wendi; Xu, Jia

    2014-01-01

    A kind of shape memory alloy (SMA) hysteretic nonlinear model is developed, and the stochastic bifurcation characteristics of SMA intravascular stents subjected to radial and axial excitations are studied in this paper. A new nonlinear differential item is introduced to interpret the hysteretic phenomena of SMA strain-stress curves, and the dynamic model of SMA intravascular stent subjected to radial and axial stochastic excitations is established. The conditions of the system's stochastic stability are determined, and the probability density function of the system response is obtained. Finally, the stochastic Hopf bifurcation characteristics of the system are analyzed. Theoretical analysis and numerical simulation show that the system stability varies with bifurcation parameters, and stochastic Hopf bifurcation occurs in the process; there are two limit cycles in the stationary probability density of the system response in some cases, which means that there are two vibration amplitudes whose probability are both very high; jumping phenomena between the two vibration amplitudes appears with the change of conditions, which may cause stent fracture or loss. The results of this paper are helpful for application of SMA intravascular stent in biomedical engineering fields.

  5. The neuroprotective effects of intravascular low level laser irradiation on cerebral ischemia rats

    NASA Astrophysics Data System (ADS)

    Qiu, Yongming; Lu, Zhaofeng; Wang, Zhongguang; Jiang, Jiyao

    2005-07-01

    The effects of intravascular low level laser irradiation of He-Ne on rat MCAo-induced cerebral injury were studied. The results showed that control rats (subjected to MCAo injury without laser treatment) at 7d exhibited striatal and cortical brain infarction in the right hemisphere from approximately 3 to 11mm from the front pole. the total infarct volume in this group was 34.5+/-8.1mm3. For experimental rats (with laser management), the total infarct volume was 29.0+/-9.0mm3. P was gained less than 0.05. The neurological score of control group was 4.7+/-0.6 and it was 5.2+/-1.0 in experimental group, comparison by statistical analysis showed P less than 0.05. The cerebral pathological damages in the control group were more severe than in experimental group. We concluded that the intravascular low level laser irradiation has no remarked complication and is helpful to reduce ischemic damage. There is clinically potential for the application of intravascular He-Ne low level laser irradiation in ischemia stroke.

  6. Use of an oxygen-carrying blood substitute to improve intravascular optical coherence tomography imaging

    NASA Astrophysics Data System (ADS)

    Hoang, Khiet C.; Edris, Ahmad; Su, Jianping; Mukai, David S.; Mahon, Sari; Petrov, Artiom D.; Kern, Morton; Ashan, Chowdhury; Chen, Zhongping; Tromberg, Bruce J.; Narula, Jagat; Brenner, Matthew

    2009-05-01

    Optical coherence tomography (OCT) is a catheter-based imaging technology with powerful resolution capable of identifying vulnerable plaques and guiding coronary intervention. However, a significant limitation of intravascular OCT imaging is its attenuation by blood. We propose that the use of an oxygen-carrying blood substitute could potentially optimize OCT image quality. Surgical isolation of the descending thoracic aorta of six rabbits is performed, followed by intravascular OCT imaging of the abdominal aorta. Perfluorodecalin (PFD) is oxygenated using a bubble-through technique with 100% oxygen. OCT imaging is performed and compared using three different flushing modalities: PFD; saline; and blood. OCT imaging of the rabbit abdominal aorta is successful in all of the subjects. In each of the six studied subjects, flushing with PFD consistently provides dramatically better imaging of the vessel wall tissue structures. OCT image quality is highly dependent on the ability of the flushing modality to remove blood from the imaging field. From this proof-of-concept study, we demonstrate that endovascular flushing with an oxygen-carrying blood substitute (PFD) is optically superior to saline flushing for intravascular imaging.

  7. A novel dual-frequency imaging method for intravascular ultrasound applications.

    PubMed

    Qiu, Weibao; Chen, Yan; Wong, Chi-Man; Liu, Baoqiang; Dai, Jiyan; Zheng, Hairong

    2015-03-01

    Intravascular ultrasound (IVUS), which is able to delineate internal structures of vessel wall with fine spatial resolution, has greatly enriched the knowledge of coronary atherosclerosis. A novel dual-frequency imaging method is proposed in this paper for intravascular imaging applications. A probe combined two ultrasonic transducer elements with different center frequencies (36 MHz and 78 MHz) is designed and fabricated with PMN-PT single crystal material. It has the ability to balance both imaging depth and resolution, which are important imaging parameters for clinical test. A dual-channel imaging platform is also proposed for real-time imaging, and this platform has been proven to support programmable processing algorithms, flexible imaging control, and raw RF data acquisition for IVUS applications. Testing results show that the -6 dB axial and lateral imaging resolutions of low-frequency ultrasound are 78 and 132 μm, respectively. In terms of high-frequency ultrasound, axial and lateral resolutions are determined to be as high as 34 and 106 μm. In vitro intravascular imaging on healthy swine aorta is conducted to demonstrate the performance of the dual-frequency imaging method for IVUS applications. PMID:25454093

  8. Development of an intravascular pumping oxygenator using a new silicone membrane.

    PubMed

    Sueda, T; Fukunaga, S; Morita, S; Sueshiro, M; Hirai, S; Okada, K; Orihashi, K; Matsuura, Y

    1997-01-01

    A new intravascular pumping oxygenator (IVPO) was developed for intravascular gas exchange and circulatory assistance in critically ill patients with respiratory and circulatory failure. The IVPO utilizes new silicone hollow fibers (diameter, 1 mm; membrane width, 50 microns) and consists of two driving tubes for the oxygenation and pumping of circulating blood. The performance characteristics of the IVPO were studied using an experiment ex vivo model. With a mean hemoglobin concentration of 10.5 +/- 2.3 g/dl, total oxygen transfer was 5.6 +/- 1.5 ml/min at a blood flow of 200 ml/min and 6.3 +/- 2.2 ml/min at a blood flow of 250 ml/min. Total CO2 transfer was 3.8 +/- 1.4 ml/min at a blood flow of 200 ml/min and 4.2 +/- 1.6 ml/min at a blood flow of 250 ml/min. Blood flow increased to a maximum of 250 ml/min during IVPO pumping. This preliminary experiment demonstrated that the IVPO has the capacity to function both as circulatory assist pump and as an intravascular hollow fiber oxygenator.

  9. Integrated intravascular ultrasound and optical-resolution photoacoustic microscopy with a 1-mm-diameter catheter

    NASA Astrophysics Data System (ADS)

    Bai, Xiaosong; Gong, Xiaojing; Lin, Riqiang; Hau, William; Song, Liang

    2014-03-01

    Intravascular ultrasound (IVUS) plays a vital role in assessing the severity of atherosclerosis and has greatly enriched our knowledge on atherosclerotic plaques. However, it mainly reveals the structural information of plaques. In contrast, spectroscopic and molecular photoacoustic imaging can potentially improve plaque composition identification, inflammation detection, and ultimately the stratification of plaque vulnerability and risk. In this work, we developed an integrated intravascular ultrasound and optical-resolution photoacoustic microscopy (IVUS-PAM) system with a single catheter as small as 1 mm in diameter, comparable to that of existing clinical IVUS catheters. In addition, by using a GRIN lens to focus the excitation laser pulse, the system provides an optical-diffraction limited photoacoustic lateral resolution as fine as 19.6 micrometers, ~10-fold finer than that of conventional intravascular photoacoustic imaging and existing IVUS technology. The system employs a custom-made miniaturized single-element ultrasonic transducer with a dimension of ~0.5 mm, a centre frequency of ~40 MHz, and a fractional bandwidth of ~60%. The IVUS-PAM can simultaneously acquire co-registered IVUS images with an axial resolution of ~40 micrometers and a lateral resolution of ~200 micrometers. In the future, IVUS-PAM may open up new opportunities for improved high-resolution vulnerable plaque imaging and image-guided stent deployment.

  10. Intravascular ultrasound characterization of the "black hole" phenomenon after drug-eluting stent implantation.

    PubMed

    Costa, Marco A; Sabate, Manel; Angiolillo, Dominick J; Jimenez-Quevedo, Pilar; Teirstein, Paul; Carter, Andrew; Leon, Martin B; Moses, Jeffrey; Zenni, Martin; Yakubov, Steven; Guzman, Luis A; Gilmore, Paul; Macaya, Carlos; Bass, Theodore A

    2006-01-15

    An intraluminal echolucent tissue, dubbed "black hole," has been identified by intravascular ultrasonography after intracoronary brachytherapy. This study reports the characteristics and incidence of the black hole in patients treated with drug-eluting stent implantation using a sirolimus-eluting stent (SES). We included intravascular ultrasound data from the Compassionate Use of Sirolimus-Eluting Stent (SECURE, n = 61 lesions) registry, a study involving patients in whom previous brachytherapy had failed, and the DIABETES trial (n = 165 lesions), a multicenter, randomized study comparing SES versus bare metal stents in diabetic patients. Intravascular ultrasound follow-up was scheduled at 8 months (SECURE trial, post-brachytherapy population) and 9 months (DIABETES trial). In the SECURE population, a black hole was observed in 10 patients (19.6%). Seven black hole segments had significant intimal hyperplasia (> 10%). A black hole accounted for 27% of total intraluminal tissue. In the DIABETES trial, 2 patients (2.5%) in the SES group and none in the bare metal stent group showed echolucent intimal hyperplasia. In conclusion, a black hole occurred frequently after implantation of a SES in patients in whom intracoronary brachytherapy had previously failed. Black holes were also identified in a nonirradiated population, although the incidence was lower than in the post-brachytherapy patients. Bare metal stents were not associated with this phenomenon.

  11. Lead-free intravascular ultrasound transducer using BZT-50BCT ceramics.

    PubMed

    Yan, Xingwei; Lam, Kwok Ho; Li, Xiang; Chen, Ruimin; Ren, Wei; Ren, Xiaobing; Zhou, Qifa; Shung, K Kirk

    2013-06-01

    This paper reports the fabrication and evaluation of a high-frequency ultrasonic transducer based on a new lead-free piezoelectric material for intravascular imaging application. Lead-free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO4(BZT-50BCT) ceramic with a high dielectric constant (~2800) was employed to develop a high-frequency (~30 MHz) needle-type ultrasonic transducer. With superior piezoelectric performance (piezoelectric coefficient d33 ~ 600 pC/N), the lead-free transducer was found to exhibit a -6-dB bandwidth of 53% with an insertion loss of 18.7 dB. In vitro intravascular ultrasound (IVUS) imaging of a human cadaver coronary artery was performed to demonstrate the potential of the lead-free transducer for biomedical imaging applications. This is the first time that a lead-free transducer has been used for IVUS imaging application. The experimental results suggest that the BZT-50BCT ceramic is a promising lead-free piezoelectric material for high-frequency intravascular imaging applications. PMID:25004492

  12. Radiation Protection in Canada

    PubMed Central

    Bird, P. M.

    1964-01-01

    The current status of radiation protection in Canada is discussed in the second of a three-part series and particular emphasis is placed on the role of the Radiation Protection Division of the Department of National Health and Welfare. Administrative and operational control procedures have been developed, involving prior approval of health safeguards in the radioisotope user's facilities and techniques, and systematic monitoring and inspection. Where necessary, a medical follow-up of accidents and excessive radiation exposures is carried out. In 1963 more than 1600 radioisotope licences were issued. Filmmonitoring service was provided to about 15,500 isotope and x-ray workers. Semiautomatic handling procedures have been developed to meet the increasing demand for film-monitoring services. Monitoring and inspection services have been provided for x-ray workers, and a committee has been formed to develop administrative procedures for health and safety control in x-ray work. Committees have also been set up to review the health and safety aspects of the operation of nuclear reactors and particle accelerators. PMID:14146856

  13. High efficiency direct thermal to electric energy conversion from radioisotope decay using selective emitters and spectrally tuned solar cells

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L.; Flood, Dennis J.; Lowe, Roland A.

    1993-01-01

    Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1200K. Both selective emitter and filter system TPV systems are feasible. However, requirements on the filter system are severe in order to attain high efficiency. A thin-film of a rare-earth oxide is one method for producing an efficient, rugged selective emitter. An efficiency of 0.14 and power density of 9.2 W/KG at 1200K is calculated for a hypothetical thin-film neodymia (Nd2O3) selective emitter TPV system that uses radioisotope decay as the thermal energy source.

  14. Preliminary investigation of parasitic radioisotope production using the LANL IPF secondary neutron flux

    NASA Astrophysics Data System (ADS)

    Engle, J. W.; Kelsey, C. T.; Bach, H.; Ballard, B. D.; Fassbender, M. E.; John, K. D.; Birnbaum, E. R.; Nortier, F. M.

    2012-12-01

    In order to ascertain the potential for radioisotope production and material science studies using the Isotope Production Facility at Los Alamos National Lab, a two-pronged investigation has been initiated. The Monte Carlo for Neutral Particles eXtended (MCNPX) code has been used in conjunction with the CINDER 90 burnup code to predict neutron flux energy distributions as a result of routine irradiations and to estimate yields of radioisotopes of interest for hypothetical irradiation conditions. A threshold foil activation experiment is planned to study the neutron flux using measured yields of radioisotopes, quantified by HPGe gamma spectroscopy, from representative nuclear reactions with known thresholds up to 50 MeV.

  15. Radioisotope electric propulsion of sciencecraft to the outer solar system and near-interstellar space

    SciTech Connect

    Noble, R.J.

    1998-08-01

    Recent results are presented in the study of radioisotope electric propulsion as a near-term technology for sending small robotic sciencecraft to the outer Solar System and near-interstellar space. Radioisotope electric propulsion (REP) systems are low-thrust, ion propulsion units based on radioisotope electric generators and ion thrusters. Powerplant specific masses are expected to be in the range of 100 to 200 kg/kW of thrust power. Planetary rendezvous missions to Pluto, fast missions to the heliopause (100 AU) with the capability to decelerate an orbiter for an extended science program and prestellar missions to the first gravitational lens focus of the Sun (550 AU) are investigated.

  16. Intravascular brachytherapy with radioactive stents produced by ion implantation

    NASA Astrophysics Data System (ADS)

    Golombeck, M.-A.; Heise, S.; Schloesser, K.; Schuessler, B.; Schweickert, H.

    2003-05-01

    About 1 million patients are treated for stenosis of coronary arteries by percutaneous balloon angioplasty annually worldwide. In many cases a so called stent is inserted into the vessel to keep it mechanically open. Restenosis is observed in about 20-30% of these cases, which can be treated by irradiating the stented vessel segment. In our approach, we utilized the stent itself as radiation source by ion implanting 32P. Investigations of the surface properties were performed with special emphasis on activity retention. Clinical data of about 400 patients showed radioactive stents can suppress instent restenosis, but a so called edge effect appeared, which can be avoided by the new "drug eluting stents".

  17. A NEW ALGORITHM FOR RADIOISOTOPE IDENTIFICATION OF SHIELDED AND MASKED SNM/RDD MATERIALS

    SciTech Connect

    Jeffcoat, R.

    2012-06-05

    Detection and identification of shielded and masked nuclear materials is crucial to national security, but vast borders and high volumes of traffic impose stringent requirements for practical detection systems. Such tools must be be mobile, and hence low power, provide a low false alarm rate, and be sufficiently robust to be operable by non-technical personnel. Currently fielded systems have not achieved all of these requirements simultaneously. Transport modeling such as that done in GADRAS is able to predict observed spectra to a high degree of fidelity; our research is focusing on a radionuclide identification algorithm that inverts this modeling within the constraints imposed by a handheld device. Key components of this work include incorporation of uncertainty as a function of both the background radiation estimate and the hypothesized sources, dimensionality reduction, and nonnegative matrix factorization. We have partially evaluated performance of our algorithm on a third-party data collection made with two different sodium iodide detection devices. Initial results indicate, with caveats, that our algorithm performs as good as or better than the on-board identification algorithms. The system developed was based on a probabilistic approach with an improved approach to variance modeling relative to past work. This system was chosen based on technical innovation and system performance over algorithms developed at two competing research institutions. One key outcome of this probabilistic approach was the development of an intuitive measure of confidence which was indeed useful enough that a classification algorithm was developed based around alarming on high confidence targets. This paper will present and discuss results of this novel approach to accurately identifying shielded or masked radioisotopes with radiation detection systems.

  18. Noninvasive in vivo plasma volume and hematocrit in humans: observing long-term baseline behavior to establish homeostasis for intravascular volume and composition

    NASA Astrophysics Data System (ADS)

    Dent, Paul; Deng, Bin; Goodisman, Jerry; Peterson, Charles M.; Narsipur, Sriram; Chaiken, J.

    2016-04-01

    A new device incorporating a new algorithm and measurement process allows simultaneous noninvasive in vivo monitoring of intravascular plasma volume and red blood cell volume. The purely optical technique involves probing fingertip skin with near infrared laser light and collecting the wavelength shifted light, that is, the inelastic emission (IE) which includes the unresolved Raman and fluorescence, and the un-shifted emission, that is, the elastic emission (EE) which includes both the Rayleigh and Mie scattered light. Our excitation and detection geometry is designed so that from these two simultaneous measurements we can calculate two parameters within the single scattering regime using radiation transfer theory, the intravascular plasma volume fraction and the red blood cell volume fraction. Previously calibrated against a gold standard FDA approved device, 2 hour monitoring sessions on three separate occasions over a three week span for a specific, motionless, and mostly sleeping individual produced 3 records containing a total of 5706 paired measurements of hematocrit and plasma volume. The average over the three runs, relative to the initial plasma volume taken as 100%, of the plasma volume±1σ was 97.56+/-0.55 or 0.56%.For the same three runs, the average relative hematocrit (Hct), referenced to an assumed initial value of 28.35 was 29.37+/-0.12 or stable to +/-0.4%.We observe local deterministic circulation effects apparently associated with the pressure applied by the finger probe as well as longer timescale behavior due to normal ebb and flow of internal fluids due to posture changes and tilt table induced gravity gradients.

  19. Modeling of Thermal Perturbations Using Raytracing Method with Preliminary Results for a Test Case Model of the Pioneer 10/11 Radioisotopic Thermal Generators

    NASA Astrophysics Data System (ADS)

    Rievers, Benny; Lämmerzahl, Claus; Dittus, Hansjörg

    2010-03-01

    Electromagnetic radiation emitted from a source carries momentum. Thus, the dissipation of waste thermal energy can produce disturbance forces on spacecraft surfaces if the energy is not dissipated in a symmetric pattern. This force can be computed for a plate element as the quotient of the radiated power in normal direction and the speed of light. Depending on mission and spacecraft design the resulting surface forces have to be included into the disturbance budget. At ZARM an elaborated method for the exact modeling of the disturbances caused by heat radiation was developed which can be used for any satellite mission with high requirements on perturbation knowledge (e.g. LISA, LISA pathfinder, MICROSCOPE). The method which will be presented in this paper is based on raytracing and finite element (FE) thermal analysis. As a demonstration of the potential of the method, preliminary results acquired with a test case model of the Pioneer 10/11 Radioisotopic Thermal Generators (RTGs) will be shown.

  20. Radioisotope Electric Propulsion (REP): A Near-Term Approach to Nuclear Propulsion

    NASA Technical Reports Server (NTRS)

    Schmidt, George R.; Manzella, David H.; Kamhawi, Hani; Kremic, Tibor; Oleson, Steven R.; Dankanich, John W.; Dudzinski, Leonard A.

    2009-01-01

    Studies over the last decade have shown radioisotope-based nuclear electric propulsion to be enhancing and, in some cases, enabling for many potential robotic science missions. Also known as radioisotope electric propulsion (REP), the technology offers the performance advantages of traditional reactor-powered electric propulsion (i.e., high specific impulse propulsion at large distances from the Sun), but with much smaller, affordable spacecraft. Future use of REP requires development of radioisotope power sources with system specific powers well above that of current systems. The US Department of Energy and NASA have developed an advanced Stirling radioisotope generator (ASRG) engineering unit, which was subjected to rigorous flight qualification-level tests in 2008, and began extended lifetime testing later that year. This advancement, along with recent work on small ion thrusters and life extension technology for Hall thrusters, could enable missions using REP sometime during the next decade.