Role of radionuclide imaging for diagnosis of device and prosthetic valve infections

PubMed Central

Sarrazin, Jean-François; Philippon, François; Trottier, Mikaël; Tessier, Michel

2016-01-01

Cardiovascular implantable electronic device (CIED) infection and prosthetic valve endocarditis (PVE) remain a diagnostic challenge. Cardiac imaging plays an important role in the diagnosis and management of patients with CIED infection or PVE. Over the past few years, cardiac radionuclide imaging has gained a key role in the diagnosis of these patients, and in assessing the need for surgery, mainly in the most difficult cases. Both 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and radiolabelled white blood cell single-photon emission computed tomography/computed tomography (WBC SPECT/CT) have been studied in these situations. In their 2015 guidelines for the management of infective endocarditis, the European Society of Cardiology incorporated cardiac nuclear imaging as part of their diagnostic algorithm for PVE, but not CIED infection since the data were judged insufficient at the moment. This article reviews the actual knowledge and recent studies on the use of 18F-FDG PET/CT and WBC SPECT/CT in the context of CIED infection and PVE, and describes the technical aspects of cardiac radionuclide imaging. It also discusses their accepted and potential indications for the diagnosis and management of CIED infection and PVE, the limitations of these tests, and potential areas of future research. PMID:27721936

Radionuclide bone imaging in the evaluation of osseous allograft systems. Scientific report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelly, J.F.; Cagle, J.D.; Stevenson, J.S.

1975-02-01

Evaluation of the progress of osteogenic activity in mandibular bone grafts in dogs by a noninvasive, nondestructive radionuclide method is feasible. The method provides a meaningful sequential interpretation of osseous repair more sensitive than conventional radiography. It is presumed that accumulating hydroxyapatite is being labelled by the imaging agent technetium diphosphonate. The osseous allograft systems studied were comparable to or exceeded autografts in their repair activity in mandibular discontinuity defects as judged by radionuclide imaging. A lyophilized mandibular allograft segment augmented with autologous cancellous marrow was more active than autograft controls at 3 and 6 weeks and was the mostmore » active system studied. Allograft segments augmented with lyophilized crushed cortical allogeneic bone particles were equal to controls at 3 weeks and more active than controls at 6 weeks. Lyophilized crushed cortical allogeneic bone particles retained in a Millipore filter while not clinically stable at 6 weeks did show osteogenic activity equal to control autografts at this interval. (GRA)« less

CloudSat First Image of a Warm Front Storm Over the Norwegian Sea

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Figure 1

CloudSat's first image, of a warm front storm over the Norwegian Sea, was obtained on May 20, 2006. In this horizontal cross-section of clouds, warm air is seen rising over colder air as the satellite travels from right to left. The red colors are indicative of highly reflective particles such as water droplets (or rain) or larger ice crystals (or snow), while the blue indicates thinner clouds (such as cirrus). The flat green/blue lines across the bottom represent the ground signal. The vertical scale on the CloudSat Cloud Profiling Radar image is approximately 30 kilometers (19 miles). The blue line below the Cloud Profiling Radar image indicates that the data were taken over water. The inset image shows the CloudSat track relative to a Moderate Resolution Imaging Spectroradiometer (MODIS) infrared image taken at nearly the same time.

Warm-Season Flows on Slope in Horowitz Crater Nine-Image Sequence

NASA Image and Video Library

2011-08-04

This image comes from observations of Horowitz crater by the HiRISE camera onboard NASA Mars Reconnaissance Orbiter. The features that extend down the slope during warm seasons are called recurring slope lineae.

A reference skeletal dosimetry model for an adult male radionuclide therapy patient based on three-dimensional imaging and paired-image radiation transport

NASA Astrophysics Data System (ADS)

Shah, Amish P.

The need for improved patient-specificity of skeletal dose estimates is widely recognized in radionuclide therapy. Current clinical models for marrow dose are based on skeletal mass estimates from a variety of sources and linear chord-length distributions that do not account for particle escape into cortical bone. To predict marrow dose, these clinical models use a scheme that requires separate calculations of cumulated activity and radionuclide S values. Selection of an appropriate S value is generally limited to one of only three sources, all of which use as input the trabecular microstructure of an individual measured 25 years ago, and the tissue mass derived from different individuals measured 75 years ago. Our study proposed a new modeling approach to marrow dosimetry---the Paired Image Radiation Transport (PIRT) model---that properly accounts for both the trabecular microstructure and the cortical macrostructure of each skeletal site in a reference male radionuclide patient. The PIRT model, as applied within EGSnrc, requires two sets of input geometry: (1) an infinite voxel array of segmented microimages of the spongiosa acquired via microCT; and (2) a segmented ex-vivo CT image of the bone site macrostructure defining both the spongiosa (marrow, endosteum, and trabeculae) and the cortical bone cortex. Our study also proposed revising reference skeletal dosimetry models for the adult male cancer patient. Skeletal site-specific radionuclide S values were obtained for a 66-year-old male reference patient. The derivation for total skeletal S values were unique in that the necessary skeletal mass and electron dosimetry calculations were formulated from the same source bone site over the entire skeleton. We conclude that paired-image radiation-transport techniques provide an adoptable method by which the intricate, anisotropic trabecular microstructure of the skeletal site; and the physical size and shape of the bone can be handled together, for improved

Radionuclides in Diagnosis.

ERIC Educational Resources Information Center

Williams, E. D.

1989-01-01

Discussed is a radionuclide imaging technique, including the gamma camera, image analysis computer, radiopharmaceuticals, and positron emission tomography. Several pictures showing the use of this technique are presented. (YP)

Radionuclides in haematology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lewis, S.M.; Bayly, R.J.

1986-01-01

This book contains the following chapters: Some prerequisites to the use of radionuclides in haematology; Instrumentation and counting techniques; In vitro techniques; Cell labelling; Protein labelling; Autoradiography; Imaging and quantitative scanning; Whole body counting; Absorption and excretion studies; Blood volume studies; Plasma clearance studies; and Radionuclide blood cell survival studies.

Tumor Immunotargeting Using Innovative Radionuclides

PubMed Central

Kraeber-Bodéré, Françoise; Rousseau, Caroline; Bodet-Milin, Caroline; Mathieu, Cédric; Guérard, François; Frampas, Eric; Carlier, Thomas; Chouin, Nicolas; Haddad, Ferid; Chatal, Jean-François; Faivre-Chauvet, Alain; Chérel, Michel; Barbet, Jacques

2015-01-01

This paper reviews some aspects and recent developments in the use of antibodies to target radionuclides for tumor imaging and therapy. While radiolabeled antibodies have been considered for many years in this context, only a few have reached the level of routine clinical use. However, alternative radionuclides, with more appropriate physical properties, such as lutetium-177 or copper-67, as well as alpha-emitting radionuclides, including astatine-211, bismuth-213, actinium-225, and others are currently reviving hopes in cancer treatments, both in hematological diseases and solid tumors. At the same time, PET imaging, with short-lived radionuclides, such as gallium-68, fluorine-18 or copper-64, or long half-life ones, particularly iodine-124 and zirconium-89 now offers new perspectives in immuno-specific phenotype tumor imaging. New antibody analogues and pretargeting strategies have also considerably improved the performances of tumor immunotargeting and completely renewed the interest in these approaches for imaging and therapy by providing theranostics, companion diagnostics and news tools to make personalized medicine a reality. PMID:25679452

Relationship of brain imaging with radionuclides and with x-ray computed tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuhl, D.E.

1981-03-03

Because of high sensitivity and specificity for altered local cerebral structure, x-ray computed tomography (CT) is the preferred initial diagnostic imaging study under most circumstances when cerebral disease is suspected. CT has no competitor for detecting fresh intracerebral hemorrhage. Radionuclide imaging (RN) scan is preferred when relative perfusion is to be assessed, in patients allergic to contrast media, and when an adequate CT study is not technically possible. (RN) plays an important complementary role to CT, especially for patients suspected of subacute or chronic subdura hematoma, cerebral infarction, arteriovenous malformations, meningitis, encephalitis, normal pressure hydrocephalus, or when CT findings aremore » inconclusive. When CT is not available, RN serves as a good screening study for suspected cerebral tumor, infection, recent infarction, arteriovenous malformation, and chronic subdural hematoma. Future improvement in radionuclide imaging by means of emission composition potential. The compound plating approacl threshold for all the investigated transistors and fast neutron spectra lies within the raal. The value of the potential slightly changes with the coordinate change in this region, i.e. the charge on a collecting electrode is not practically guided up to a certain moment of time during the movement of nonequilibrium carriers.« less

Imaging quality of (44)Sc in comparison with five other PET radionuclides using Derenzo phantoms and preclinical PET.

PubMed

Bunka, Maruta; Müller, Cristina; Vermeulen, Christiaan; Haller, Stephanie; Türler, Andreas; Schibli, Roger; van der Meulen, Nicholas P

2016-04-01

PET is the favored nuclear imaging technique because of the high sensitivity and resolution it provides, as well as the possibility for quantification of accumulated radioactivity. (44)Sc (T1/2=3.97h, Eβ(+)=632keV) was recently proposed as a potentially interesting radionuclide for PET. The aim of this study was to investigate the image quality, which can be obtained with (44)Sc, and compare it with five other, frequently employed PET nuclides using Derenzo phantoms and a small-animal PET scanner. The radionuclides were produced at the medical cyclotron at CRS, ETH Zurich ((11)C, (18)F), at the Injector II research cyclotron at CRS, PSI ((64)Cu, (89)Zr, (44)Sc), as well as via a generator system ((68)Ga). Derenzo phantoms, containing solutions of each of these radionuclides, were scanned using a GE Healthcare eXplore VISTA small-animal PET scanner. The image resolution was determined for each nuclide by analysis of the intensity signal using the reconstructed PET data of a hole diameter of 1.3mm. The image quality of (44)Sc was compared to five frequently-used PET radionuclides. In agreement with the positron range, an increasing relative resolution was determined in the sequence of (68)Ga<(44)Sc<(89)Zr<(11)C<(64)Cu<(18)F. The performance of (44)Sc was in agreement with the theoretical expectations based on the energy of the emitted positrons. Copyright © 2016 Elsevier Ltd. All rights reserved.

Molecular Imaging and Radionuclide Therapy of Melanoma Targeting the Melanocortin 1 Receptor

PubMed Central

Zhang, Chengcheng; Lin, Kuo-Shyan; Bénard, François

2017-01-01

Melanoma is a deadly disease at late metastatic stage, and early diagnosis and accurate staging remain the key aspects for managing melanoma. The melanocortin 1 receptor (MC1 R) is overexpressed in primary and metastatic melanomas, and its endogenous ligand, the α-melanocyte-stimulating hormone (αMSH), has been extensively studied for the development of MC1 R-targeted molecular imaging and therapy of melanoma. Natural αMSH is not well suited for this purpose due to low stability in vivo. Unnatural amino acid substitutions substantially stabilized the peptide, while cyclization via lactam bridge and metal coordination further improved binding affinity and stability. In this study, we summarized the development and the in vitro and in vivo characteristics of the radiolabeled αMSH analogues, including 99mTc-, 111In-, 67 Ga-, or 125I-labeled αMSH analogues for imaging with single-photon emission computed tomography; 68Ga-, 64Cu-, or 18F-labeled αMSH analogues for imaging with positron emission tomography; and 188Re-, 177Lu-, 90Y-, or 212Pb-labeled αMSH analogues for radionuclide therapy. These radiolabeled αMSH analogues showed promising results with high tumor uptake and rapid normal tissue activity clearance in the preclinical model of B16F1 and B16F10 mouse melanomas. These results highlight the potential of using radiolabeled αMSH analogues in clinical applications for molecular imaging and radionuclide therapy of melanoma. PMID:29182034

Multimodal nanoprobes for radionuclide and five-color near-infrared optical lymphatic imaging.

PubMed

Kobayashi, Hisataka; Koyama, Yoshinori; Barrett, Tristan; Hama, Yukihiro; Regino, Celeste A S; Shin, In Soo; Jang, Beom-Su; Le, Nhat; Paik, Chang H; Choyke, Peter L; Urano, Yasuteru

2007-11-01

Current contrast agents generally have one function and can only be imaged in monochrome; therefore, the majority of imaging methods can only impart uniparametric information. A single nanoparticle has the potential to be loaded with multiple payloads. Such multimodality probes have the ability to be imaged by more than one imaging technique, which could compensate for the weakness or even combine the advantages of each individual modality. Furthermore, optical imaging using different optical probes enables us to achieve multicolor in vivo imaging, wherein multiple parameters can be read from a single image. To allow differentiation of multiple optical signals in vivo, each probe should have a close but different near-infrared emission. To this end, we synthesized nanoprobes with multimodal and multicolor potential, which employed a polyamidoamine dendrimer platform linked to both radionuclides and optical probes, permitting dual-modality scintigraphic and five-color near-infrared optical lymphatic imaging using a multiple-excitation spectrally resolved fluorescence imaging technique.

Imaging regional renal function parameters using radionuclide tracers

NASA Astrophysics Data System (ADS)

Qiao, Yi

A compartmental model is given for evaluating kidney function accurately and noninvasively. This model is cast into a parallel multi-compartment structure and each pixel region (picture element) of kidneys is considered as a single kidney compartment. The loss of radionuclide tracers from the blood to the kidney and from the kidney to the bladder are modelled in great detail. Both the uptake function and the excretion function of the kidneys can be evaluated pixel by pixel, and regional diagnostic information on renal function is obtained. Gamma Camera image data are required by this model and a screening test based renal function measurement is provided. The regional blood background is subtracted from the kidney region of interest (ROI) and the kidney regional rate constants are estimated analytically using the Kuhn-Pucker multiplier method in convex programming by considering the input/output behavior of the kidney compartments. The detailed physiological model of the peripheral compartments of the system, which is not available for most radionuclide tracers, is not required in the determination of the kidney regional rate constants and the regional blood background factors within the kidney ROI. Moreover, the statistical significance of measurements is considered to assure the improved statistical properties of the estimated kidney rate constants. The relations between various renal function parameters and the kidney rate constants are established. Multiple renal function measurements can be found from the renal compartmental model. The blood radioactivity curve and the regional (or total) radiorenogram determining the regional (or total) summed behavior of the kidneys are obtained analytically with the consideration of the statistical significance of measurements using convex programming methods for a single peripheral compartment system. In addition, a new technique for the determination of 'initial conditions' in both the blood compartment and the kidney

The rise of global warming skepticism: exploring affective image associations in the United States over time.

PubMed

Smith, Nicholas; Leiserowitz, Anthony

2012-06-01

This article explores how affective image associations to global warming have changed over time. Four nationally representative surveys of the American public were conducted between 2002 and 2010 to assess public global warming risk perceptions, policy preferences, and behavior. Affective images (positive or negative feelings and cognitive representations) were collected and content analyzed. The results demonstrate a large increase in "naysayer" associations, indicating extreme skepticism about the issue of climate change. Multiple regression analyses found that holistic affect and "naysayer" associations were more significant predictors of global warming risk perceptions than cultural worldviews or sociodemographic variables, including political party and ideology. The results demonstrate the important role affective imagery plays in judgment and decision-making processes, how these variables change over time, and how global warming is currently perceived by the American public. © 2012 Society for Risk Analysis.

Flow and Transport of Radionuclides in the Rhizosphere: Imaging and Measurements in a 2D System

NASA Astrophysics Data System (ADS)

Pales, Ashley; Darnault, Christophe; Li, Biting; Clifford, Heather; Montgomery, Dawn; Moysey, Stephen; Powell, Brian; DeVol, Tim; Erdmann, Bryan; Edayilam, Nimisha; Tharayil, Nishanth; Dogan, Mine; Martinez, Nicole

2017-04-01

This research aims to build upon past 2D tank light transmission methods to quantify real-time flow in unsaturated porous media, understand how exudates effect unstable flow patterns, and understand radionuclide mobility and dispersion in the subsurface. A 2D tank light transmission method was created using a transparent flow through tank coupled with a random rainfall simulator; a commercial LED light and a CMOS DSLR Nikon D5500 camera were used to capture the real-time flow images. The images were broken down from RGB into HVI and analyzed in Matlab to produce quantifiable data about finger formation and water saturation distribution. Radionuclide locations were determined via handheld gamma scanner. Water saturation along the vertical and horizontal profile (Matlab) was used to quantify the finger more objectively than by eye assessment alone. The changes in finger formation and speed of propagation between the control rain water (0.01M NaCl) and the solutions containing plant exudates illustrates that the plant exudates increased the wettability (mobility) of water moving through unsaturated porous media. This understanding of plant exudates effect on unsaturated flow is important for works studying how plants, their roots and exudates, may affect the mobility of radionuclides in unsaturated porous media. As there is an increase in exudate concentration, the mobility of the radionuclides due to changing flow pattern and available water content in porous media may be improved causing more dispersion in the porous media and intake into the plant. Changes in plant root exudation impact the distribution and density of radionuclides in the rhizosphere and vadose zone.

THERANOSTICS: From Molecular Imaging Using Ga-68 Labeled Tracers and PET/CT to Personalized Radionuclide Therapy - The Bad Berka Experience.

PubMed

Baum, Richard P; Kulkarni, Harshad R

2012-01-01

The acronym THERANOSTICS epitomizes the inseparability of diagnosis and therapy, the pillars of medicine and takes into account personalized management of disease for a specific patient. Molecular phenotypes of neoplasms can be determined by molecular imaging with specific probes using positron emission tomography (PET), single photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), or optical methods, so that the treatment is specifically targeted against the tumor and its environment. To meet these demands, we need to define the targets, ligands, coupling and labeling chemistry, the most appropriate radionuclides, biodistribution modifiers, and finally select the right patients for the personalized treatment. THERANOSTICS of neuroendocrine tumors (NETs) using Ga-68 labeled tracers for diagnostics with positron emission tomography/ computed tomography (PET/CT), and using Lu-177 or other metallic radionuclides for radionuclide therapy by applying the same peptide proves that personalized radionuclide therapy today is already a fact and not a fiction.

Radionuclide Therapies in Molecular Imaging and Precision Medicine.

PubMed

Kendi, A Tuba; Moncayo, Valeria M; Nye, Jonathon A; Galt, James R; Halkar, Raghuveer; Schuster, David M

2017-01-01

This article reviews recent advances and applications of radionuclide therapy. Individualized precision medicine, new treatments, and the evolving role of radionuclide therapy are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

THERANOSTICS: From Molecular Imaging Using Ga-68 Labeled Tracers and PET/CT to Personalized Radionuclide Therapy - The Bad Berka Experience

PubMed Central

Baum, Richard P.; Kulkarni, Harshad R.

2012-01-01

The acronym THERANOSTICS epitomizes the inseparability of diagnosis and therapy, the pillars of medicine and takes into account personalized management of disease for a specific patient. Molecular phenotypes of neoplasms can be determined by molecular imaging with specific probes using positron emission tomography (PET), single photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), or optical methods, so that the treatment is specifically targeted against the tumor and its environment. To meet these demands, we need to define the targets, ligands, coupling and labeling chemistry, the most appropriate radionuclides, biodistribution modifiers, and finally select the right patients for the personalized treatment. THERANOSTICS of neuroendocrine tumors (NETs) using Ga-68 labeled tracers for diagnostics with positron emission tomography/ computed tomography (PET/CT), and using Lu-177 or other metallic radionuclides for radionuclide therapy by applying the same peptide proves that personalized radionuclide therapy today is already a fact and not a fiction. PMID:22768024

Image guidance, treatment planning and evaluation of cancer interstitial focal therapy using liposomal radionuclides

NASA Astrophysics Data System (ADS)

Ware, Steve William

Focally ablative therapy of cancer has gained significant interest recently. Improvements in diagnostic techniques have created possibilities for treatment which were once clinically unfeasible. Imaging must be capable of allowing accurate diagnosis, staging and planning upon initiation of therapy. Recent improvements in MRI and molecular imaging techniques have made it possible to accurately localize lesions and in so doing, improve the accuracy of proposed focal treatments. Using multimodality imaging it is now possible to target, plan and evaluate interstitial focal treatment using liposome encapsulated beta emitting radionuclides in a variety of cancer types. Since most absorbed dose is deposited early and heterogeneously in beta-radionuclide therapy, investigation of the resultant molecular and cellular events during this time is important for evaluating treatment efficacy. Additionally, investigating a multifocal entity such as prostate cancer is helpful for determining whether MRI is capable of discriminating the proper lesion for therapy. Correlation of MRI findings with histopathology can further improve the accuracy of interstitial focal radionuclide therapy by providing non-invasive surrogates for tissue compartment sizes. In the application of such therapies, compartmental sizes are known to heavily influence the distribution of injected agents. This has clear dosimetric implications with the potential to significantly alter the efficacy of treatment. The hypothesis of this project was that multimodality imaging with magnetic resonance imaging (MRI), autoradiography (AR), and single photon emission computed tomography (SPECT) could be used to target, plan, and evaluate interstitial focal therapy with non-sealed source, liposome-encapsulated 186Re beta emitting radionuclides. The specific aims of this project were to 1) Identify suitable targets for interstitial focal therapy. This was done by retrospectively analyzing MRI data to characterize the tumor

Imaging, Mapping and Monitoring Environmental Radionuclide Transport Using Compton-Geometry Gamma Camera

NASA Astrophysics Data System (ADS)

Bridge, J. W.; Dormand, J.; Cooper, J.; Judson, D.; Boston, A. J.; Bankhead, M.; Onda, Y.

2014-12-01

The legacy to-date of the nuclear disaster at Fukushima Dai-ichi, Japan, has emphasised the fundamental importance of high quality radiation measurements in soils and plant systems. Current-generation radiometers based on coded-aperture collimation are limited in their ability to locate sources of radiation in three dimensions, and require a relatively long measurement time due to the poor efficiency of the collimation system. The quality of data they can provide to support biogeochemical process models in such systems is therefore often compromised. In this work we report proof-of-concept experiments demonstrating the potential of an alternative approach in the measurement of environmentally-important radionuclides (in particular 137Cs) in quartz sand and soils from the Fukushima exclusion zone. Compton-geometry imaging radiometers harness the scattering of incident radiation between two detectors to yield significant improvements in detection efficiency, energy resolution and spatial location of radioactive sources in a 180° field of view. To our knowledge we are reporting its first application to environmentally-relevant systems at low activity, dispersed sources, with significant background radiation and, crucially, movement over time. We are using a simple laboratory column setup to conduct one-dimensional transport experiments for 139Ce and 137Cs in quartz sand and in homogenized repacked Fukushima soils. Polypropylene columns 15 cm length with internal diameter 1.6 cm were filled with sand or soil and saturated slowly with tracer-free aqueous solutions. Radionuclides were introduced as 2mL pulses (step-up step-down) at the column inlet. Data were collected continuously throughout the transport experiment and then binned into sequential time intervals to resolve the total activity in the column and its progressive movement through the sand/soil. The objective of this proof-of-concept work is to establish detection limits, optimise image reconstruction

Techniques for Loading Technetium-99m and Rhenium-186/188 Radionuclides into Preformed Liposomes for Diagnostic Imaging and Radionuclide Therapy.

PubMed

Goins, Beth; Bao, Ande; Phillips, William T

2017-01-01

Liposomes can serve as carriers of radionuclides for diagnostic imaging and therapeutic applications. Herein, procedures are outlined for radiolabeling liposomes with the gamma-emitting radionuclide, technetium-99m ( 99m Tc), for noninvasive detection of disease and for monitoring the pharmacokinetics and biodistribution of liposomal drugs, and/or with therapeutic beta-emitting radionuclides, rhenium-186/188 ( 186/188 Re), for radionuclide therapy. These efficient and practical liposome radiolabeling methods use a post-labeling mechanism to load 99m Tc or 186/188 Re into preformed liposomes prepared in advance of the labeling procedure. For all liposome radiolabeling methods described, a lipophilic chelator is used to transport 99m Tc or 186/188 Re across the lipid bilayer of the preformed liposomes. Once within the liposome interior, the pre-encapsulated glutathione or ammonium sulfate (pH) gradient provides for stable entrapment of the 99m Tc and 186/188 Re within the liposomes. In the first method, 99m Tc is transported across the lipid bilayer by the lipophilic chelator, hexamethylpropyleneamine oxime (HMPAO) and 99m Tc-HMPAO becomes trapped by interaction with the pre-encapsulated glutathione within the liposomes. In the second method, 99m Tc or 186/188 Re is transported across the lipid bilayer by the lipophilic chelator, N,N-bis(2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA), and 99m Tc-BMEDA or 186/188 Re-BMEDA becomes trapped by interaction with pre-encapsulated glutathione within the liposomes. In the third method, an ammonium sulfate (pH) gradient loading technique is employed using liposomes with an extraliposomal pH of 7.4 and an interior pH of 5.1. BMEDA, which is lipophilic at pH 7.4, serves as a lipophilic chelator for 99m Tc or 186/188 Re to transport the radionuclides across the lipid bilayer. Once within the more acidic liposome interior, 99m Tc/ 186/188 Re-BMEDA complex becomes protonated and more hydrophilic, which results in stable

Radionuclide Imaging of Neurohormonal System of the Heart

PubMed Central

Chen, Xinyu; Werner, Rudolf A.; Javadi, Mehrbod S.; Maya, Yoshifumi; Decker, Michael; Lapa, Constantin; Herrmann, Ken; Higuchi, Takahiro

2015-01-01

Heart failure is one of the growing causes of death especially in developed countries due to longer life expectancy. Although many pharmacological and instrumental therapeutic approaches have been introduced for prevention and treatment of heart failure, there are still limitations and challenges. Nuclear cardiology has experienced rapid growth in the last few decades, in particular the application of single photon emission computed tomography (SPECT) and positron emission tomography (PET), which allow non-invasive functional assessment of cardiac condition including neurohormonal systems involved in heart failure; its application has dramatically improved the capacity for fundamental research and clinical diagnosis. In this article, we review the current status of applying radionuclide technology in non-invasive imaging of neurohormonal system in the heart, especially focusing on the tracers that are currently available. A short discussion about disadvantages and perspectives is also included. PMID:25825596

An automated voxelized dosimetry tool for radionuclide therapy based on serial quantitative SPECT/CT imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jackson, Price A.; Kron, Tomas; Beauregard, Jean-Mathieu

2013-11-15

Purpose: To create an accurate map of the distribution of radiation dose deposition in healthy and target tissues during radionuclide therapy.Methods: Serial quantitative SPECT/CT images were acquired at 4, 24, and 72 h for 28 {sup 177}Lu-octreotate peptide receptor radionuclide therapy (PRRT) administrations in 17 patients with advanced neuroendocrine tumors. Deformable image registration was combined with an in-house programming algorithm to interpolate pharmacokinetic uptake and clearance at a voxel level. The resultant cumulated activity image series are comprised of values representing the total number of decays within each voxel's volume. For PRRT, cumulated activity was translated to absorbed dose basedmore » on Monte Carlo-determined voxel S-values at a combination of long and short ranges. These dosimetric image sets were compared for mean radiation absorbed dose to at-risk organs using a conventional MIRD protocol (OLINDA 1.1).Results: Absorbed dose values to solid organs (liver, kidneys, and spleen) were within 10% using both techniques. Dose estimates to marrow were greater using the voxelized protocol, attributed to the software incorporating crossfire effect from nearby tumor volumes.Conclusions: The technique presented offers an efficient, automated tool for PRRT dosimetry based on serial post-therapy imaging. Following retrospective analysis, this method of high-resolution dosimetry may allow physicians to prescribe activity based on required dose to tumor volume or radiation limits to healthy tissue in individual patients.« less

PSMA Ligands for Radionuclide Imaging and Therapy of Prostate Cancer: Clinical Status

PubMed Central

Lütje, Susanne; Heskamp, Sandra; Cornelissen, Alexander S.; Poeppel, Thorsten D.; van den Broek, Sebastiaan A. M. W.; Rosenbaum-Krumme, Sandra; Bockisch, Andreas; Gotthardt, Martin; Rijpkema, Mark; Boerman, Otto C.

2015-01-01

Prostate cancer (PCa) is the most common malignancy in men worldwide, leading to substantial morbidity and mortality. At present, imaging of PCa has become increasingly important for staging, restaging, and treatment selection. Until recently, choline-based positron emission tomography/computed tomography (PET/CT) represented the state-of-the-art radionuclide imaging technique for these purposes. However, its application is limited to patients with high PSA levels and Gleason scores. Prostate-specific membrane antigen (PSMA) is a promising new target for specific imaging of PCa, because it is upregulated in the majority of PCa. Moreover, PSMA can serve as a target for therapeutic applications. Currently, several small-molecule PSMA ligands with excellent in vivo tumor targeting characteristics are being investigated for their potential in theranostic applications in PCa. Here, a review of the recent developments in PSMA-based diagnostic imaging and therapy in patients with PCa with radiolabeled PSMA ligands is provided. PMID:26681984

Multi-Modal Nano-Probes for Radionuclide and 5-color Near Infrared Optical Lymphatic Imaging

PubMed Central

Kobayashi, Hisataka; Koyama, Yoshinori; Barrett, Tristan; Hama, Yukihiro; Regino, Celeste A. S.; Shin, In Soo; Jang, Beom-Su; Le, Nhat; Paik, Chang H.; Choyke, Peter L.; Urano, Yasuteru

2008-01-01

Current contrast agents generally have one function and can only be imaged in monochrome, therefore, the majority of imaging methods can only impart uniparametric information. A single nano-particle has the potential to be loaded with multiple payloads. Such multi-modality probes have the ability to be imaged by more than one imaging technique, which could compensate for the weakness or even combine the advantages of each individual modality. Furthermore, optical imaging using different optical probes enables us to achieve multi-color in vivo imaging, wherein multiple parameters can be read from a single image. To allow differentiation of multiple optical signals in vivo, each probe should have a close but different near infrared emission. To this end, we synthesized nano-probes with multi-modal and multi-color potential, which employed a polyamidoamine dendrimer platform linked to both radionuclides and optical probes, permitting dual-modality scintigraphic and 5-color near infrared optical lymphatic imaging using a multiple excitation spectrally-resolved fluorescence imaging technique. PMID:19079788

Scatter and crosstalk corrections for {sup 99m}Tc/{sup 123}I dual-radionuclide imaging using a CZT SPECT system with pinhole collimators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fan, Peng; Hutton, Brian F.; Holstensson, Maria

2015-12-15

Purpose: The energy spectrum for a cadmium zinc telluride (CZT) detector has a low energy tail due to incomplete charge collection and intercrystal scattering. Due to these solid-state detector effects, scatter would be overestimated if the conventional triple-energy window (TEW) method is used for scatter and crosstalk corrections in CZT-based imaging systems. The objective of this work is to develop a scatter and crosstalk correction method for {sup 99m}Tc/{sup 123}I dual-radionuclide imaging for a CZT-based dedicated cardiac SPECT system with pinhole collimators (GE Discovery NM 530c/570c). Methods: A tailing model was developed to account for the low energy tail effectsmore » of the CZT detector. The parameters of the model were obtained using {sup 99m}Tc and {sup 123}I point source measurements. A scatter model was defined to characterize the relationship between down-scatter and self-scatter projections. The parameters for this model were obtained from Monte Carlo simulation using SIMIND. The tailing and scatter models were further incorporated into a projection count model, and the primary and self-scatter projections of each radionuclide were determined with a maximum likelihood expectation maximization (MLEM) iterative estimation approach. The extracted scatter and crosstalk projections were then incorporated into MLEM image reconstruction as an additive term in forward projection to obtain scatter- and crosstalk-corrected images. The proposed method was validated using Monte Carlo simulation, line source experiment, anthropomorphic torso phantom studies, and patient studies. The performance of the proposed method was also compared to that obtained with the conventional TEW method. Results: Monte Carlo simulations and line source experiment demonstrated that the TEW method overestimated scatter while their proposed method provided more accurate scatter estimation by considering the low energy tail effect. In the phantom study, improved defect contrasts

Techniques for loading technetium-99m and rhenium-186/188 radionuclides into pre-formed liposomes for diagnostic imaging and radionuclide therapy.

PubMed

Goins, Beth; Bao, Ande; Phillips, William T

2010-01-01

Liposomes can serve as carriers of radionuclides for diagnostic imaging and therapeutic applications. Herein, procedures are outlined for radiolabeling liposomes with the gamma-emitting radionuclide, technetium-99m ((99m)Tc), for non-invasive detection of disease and for monitoring the pharmacokinetics and biodistribution of liposomal drugs, and/or with therapeutic beta-emitting radionuclides, rhenium-186/188 ((186/188)Re), for radionuclide therapy. These efficient and practical liposome radiolabeling methods use a post-labeling mechanism to load (99m)Tc or (186/188)Re into pre-formed liposomes prepared in advance of the labeling procedure. For all liposome radiolabeling methods described, a lipophilic chelator is used to transport (99m)Tc or (186/188)Re across the lipid bilayer of the pre-formed liposomes. Once within the liposome interior, the pre-encapsulated glutathione or ammonium sulfate (pH) gradient provides for stable entrapment of the (99m)Tc and (186/188)Re within the liposomes. In the first method, (99m)Tc is transported across the lipid bilayer by the lipophilic chelator, hexamethylpropyleneamine oxime (HMPAO) and (99m)Tc-HMPAO becomes trapped by interaction with the pre-encapsulated glutathione within the liposomes. In the second method, (99m)Tc or (186/188)Re is transported across the lipid bilayer by the lipophilic chelator, N,N-bis(2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA), and (99m)Tc-BMEDA or (186/188)Re-BMEDA becomes trapped by interaction with pre-encapsulated glutathione within the liposomes. In the third method, an ammonium sulfate (pH) gradient loading technique is employed using liposomes with an extraliposomal pH of 7.4 and an interior pH of 5.1. BMEDA, which is lipophilic at pH 7.4, serves as a lipophilic chelator for (99m)Tc or (186/188)Re to transport the radionuclides across the lipid bilayer. Once within the more acidic liposome interior, (99m)Tc/(186/188)Re-BMEDA complex becomes protonated and more hydrophilic, which

Radionuclide imaging in herpes simplex encephalitis. [/sup 99m/Tc tracer techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karlin, C.A.; Robinson, R.G.; Hinthorn, D.R.

1978-01-01

Eight patients with herpes simplex encephalitis among the 10 cases diagnosed at the University of Kansas Medical Center from 1966 to 1976 were studied with /sup 99m/Tc early in their diagnostic work-up. The images were unilaterally positive in the temporal lobe area in all 8 patients. Radionuclide studies can suggest herpes simplex as the specific etiology in cases of encephalitis and can also indicate the best site for brain biopsy to confirm the diagnosis by fluorescent antibody techniques. Appropriate antiviral therapy should be instituted as soon as possible to alter the course of this destructive form of viral encephalitis.

[Preparation, quality control and thyroid molecule imaging of solid-target based radionuclide ioine-124].

PubMed

Zhu, H; Wang, F; Guo, X Y; Li, L Q; Duan, D B; Liu, Z B; Yang, Z

2018-04-18

To provide useful information for the further production and application of this novel radio-nuclide for potential clinical application. 124 Te (p,n) 124 I nuclide reaction was used for the 124 I production. Firstly, the target material, 124 TeO 2 (200 mg) and Al2O3 (30 mg) mixture, were compressed into the round platinum based solid target by tablet device. HM-20 medical cyclotron was applied to irradiate the solid target slice for 6-10 h with helium and water cooling. Then, the radiated solid target was placed for 12 h (overnight) to decay the radioactive impurity; finally, 124 I was be purified by dry distillation using 1 mL/min nitrogen for about 6 hours and radiochemical separation methods. Micro-PET imaging studies were performed to investigate the metabolism properties and thyroid imaging ability of 124 I.After 740 kBq 124 I was injected intravenously into the tail vein of the normal mice, the animals were imaged with micro-PET and infused with CT. The micro-PET/CT infusion imaging revealed actual state 124 I's metabolism in the mice. It was been successfully applied for 200 mg 124 TeO 2 plating by the tablet device on the surface of platinum. It showed smooth, dense surface and without obviously pits and cracks. The enriched 124 Te target was irradiated for 6 to 10 hours at about 12.0 MeV with 20 μA current on HM-20 cyclotron. Then 370-1 110 MBq 124 I could be produced on the solid target after irradiation and 370-740 MBq high specific activity could be collected afterdry distillation separation and radio-chemical purification. 124 I product was finally dissolved in 0.01 mol/L NaOH for the future distribution. The gamma spectrum of the produced 124 I-solution showed that radionuclide purity was over 80.0%. The micro-PET imaging of 124 I in the normal mice exhibited the thyroid and stomach accumulations and kidney metabolism, the bladder could also be clearly visible, which was in accordance with what was previously reported. To the best of our knowledge

A Monte Carlo study on {sup 223}Ra imaging for unsealed radionuclide therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takahashi, Akihiko, E-mail: takahsr@hs.med.kyushu-u.ac.jp; Miwa, Kenta; Sasaki, Masayuki

Purpose: Radium-223 ({sup 223}Ra), an α-emitting radionuclide, is used in unsealed radionuclide therapy for metastatic bone tumors. The demand for qualitative {sup 223}Ra imaging is growing to optimize dosimetry. The authors simulated {sup 223}Ra imaging using an in-house Monte Carlo simulation code and investigated the feasibility and utility of {sup 223}Ra imaging. Methods: The Monte Carlo code comprises two modules, HEXAGON and NAI. The HEXAGON code simulates the photon and electron interactions in the tissues and collimator, and the NAI code simulates the response of the NaI detector system. A 3D numeric phantom created using computed tomography images of amore » chest phantom was installed in the HEXAGON code. {sup 223}Ra accumulated in a part of the spine, and three x-rays and 19 γ rays between 80 and 450 keV were selected as the emitted photons. To evaluate the quality of the {sup 223}Ra imaging, the authors also simulated technetium-99m ({sup 99m}Tc) imaging under the same conditions and compared the results. Results: The sensitivities of the three photopeaks were 147 counts per unit of source activity (cps MBq{sup −1}; photopeak: 84 keV, full width of energy window: 20%), 166 cps MBq{sup −1} (154 keV, 15%), and 158 cps MBq{sup −1} (270 keV, 10%) for a low-energy general-purpose (LEGP) collimator, and those for the medium-energy general-purpose (MEGP) collimator were 33, 13, and 8.0 cps MBq{sup −1}, respectively. In the case of {sup 99m}Tc, the sensitivity was 55 cps MBq{sup −1} (141 keV, 20%) for LEGP and 52 cps MBq{sup −1} for MEGP. The fractions of unscattered photons of the total photons reflecting the image quality were 0.09 (84 keV), 0.03 (154 keV), and 0.02 (270 keV) for the LEGP collimator and 0.41, 0.25, and 0.50 for the MEGP collimator, respectively. Conversely, this fraction was approximately 0.65 for the simulated {sup 99m}Tc imaging. The sensitivity with the LEGP collimator appeared very high. However, almost all of the counts

Radionuclide Methods and Instrumentation for Breast Cancer Detection and Diagnosis

PubMed Central

Surti, Suleman

2013-01-01

Breast cancer mammography is a well-acknowledged technique for patient screening due to its high sensitivity. However, in addition to its low specificity the sensitivity of mammography is limited when imaging patients with dense breasts. Radionuclide imaging techniques, such as coincidence photon-based positron emission tomography and single photon emission computed tomography or scintimammography, can play a role in assisting screening of such patients. Radionuclide techniques can also be useful in assessing treatment response of patients with breast cancer to therapy, and staging of patients to diagnose the disease extent. However, the performance of these imaging modalities is generally limited because of the poor spatial resolution and sensitivity of the commercially available multipurpose imaging systems. Here, we describe some of the dedicated imaging systems (positron emission mammography [PEM] and breast-specific gamma imaging [BSGI]) that have been developed both commercially and in research laboratories for radionuclide imaging of breast cancer. Clinical studies with dedicated PEM scanners show improved sensitivity to detecting cancer in patients when using PEM in conjunction with additional imaging modalities, such as magnetic resonance imaging or mammography or both, as well as improved disease staging that can have an effect on surgical planning. High-resolution BSGI systems are more widely available commercially and several clinical studies have shown very high sensitivity and specificity in detecting cancer in high-risk patients. Further development of dedicated PEM and BSGI systems is ongoing, promising further expansion of radionuclide imaging techniques in the realm of breast cancer detection and treatment. PMID:23725989

Micro–Single-Photon Emission Computed Tomography Image Acquisition and Quantification of Sodium-Iodide Symporter–Mediated Radionuclide Accumulation in Mouse Thyroid and Salivary Glands

PubMed Central

Brandt, Michael P.; Kloos, Richard T.; Shen, Daniel H.; Zhang, Xiaoli; Liu, Yu-Yu

2012-01-01

Background Micro–single-photon emission computed tomography (SPECT) provides a noninvasive way to evaluate the effects of genetic and/or pharmacological modulation on sodium-iodide symporter (NIS)–mediated radionuclide accumulation in mouse thyroid and salivary glands. However, parameters affecting image acquisition and analysis of mouse thyroids and salivary glands have not been thoroughly investigated. In this study, we investigated the effects of region-of-interest (ROI) selection, collimation, scan time, and imaging orbit on image acquisition and quantification of thyroidal and salivary radionuclide accumulation in mice. Methods The effects of data window minima and maxima on thyroidal and salivary ROI selection using a visual boundary method were examined in SPECT images acquired from mice injected with 123I NaI. The effects of collimation, scan time, and imaging orbit on counting linearity and signal intensity were investigated using phantoms filled with various activities of 123I NaI or Tc-99m pertechnetate. Spatial resolution of target organs in whole-animal images was compared between circular orbit with parallel-hole collimation and spiral orbit with five-pinhole collimation. Lastly, the inter-experimental variability of the same mouse scanned multiple times was compared with the intra-experimental variability among different mice scanned at the same time. Results Thyroid ROI was separated from salivary glands by empirically increasing the data window maxima. Counting linearity within the range of 0.5–14.2 μCi was validated by phantom imaging using single- or multiple-pinhole collimators with circular or spiral imaging orbit. Scanning time could be shortened to 15 minutes per mouse without compromising counting linearity despite proportionally decreased signal intensity. Whole-animal imaging using a spiral orbit with five-pinhole collimators achieved a high spatial resolution and counting linearity. Finally, the extent of inter

TU-F-12A-06: BEST IN PHYSICS (IMAGING) - A Novel Catheter-Based Radionuclide Imaging System to Characterize Atherosclerotic Plaque

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zaman, R; Kosuge, H; Carpenter, C

2014-06-15

Purpose: Atherosclerosis underlies coronary artery diseases, the leading cause of death in the United States and worldwide. In this study, we developed a novel catheter-based radionuclide imaging (CRI) system to image 18F-fluorodeoxyglucose (18F-FDG), a radionuclide, a marker of vascular inflammation, in murine carotid arteries and characterized the system for spatial resolution from multiple scintillating materials. Methods: The catheter system includes 35 mm and 8 mm fixed focal length lenses, which are subsequently connected to a CMOS camera and fiber holder. The distal ferrule of an image bundle is terminated with a wide-angle lens. The novelty of this system is amore » scintillating balloon with a crystal tip in the front of the wide angle lens to image light from the decay of 18F-FDG emission signal. The scintillating balloon is fabricated from 1mL of silicone RTV catalyst mixed with 1 mL base and 50 mg/mL calcium fluoride doped with Europium (CaF2:Eu). To identify the optimal scintillating materials with respect to resolution, we calculated modulation transfer function (MTF) of Yttrium Aluminum Garnet doped with Cerium (YAG:Ce), anthracene, and CaF2:Eu phosphors using a thin line optical phantom (Fig. 1a-1b). Macrophage-rich FVB murine atherosclerotic carotid plaque model (n = 4) was used in ex vivo experiments. Confirmatory imaging was also performed by an external optical imaging system (IVIS-200). Results: Analysis of the different phosphors (Fig 1b) showed that CaF2:Eu enabled the best resolution of 1.2μm. The CRI system visualized 18F-FDG in atherosclerotic plaques (Fig. 1d). The ligated left carotid (LR) artery exhibited 4× higher 18F-FDG signal intensity compared to the non-ligated right carotid (negative control) artery (1.65×10{sup 2} ±4.07×10{sup 1} vs. 4.44×10{sup 1}±2.17×10{sup 0}, A.U., p = 0.005) and confirmed with IVIS-200 (Fig. 1d). Conclusion: This CRI system enables high-resolution and sensitive detection of 18F-FDG uptake by

Radionuclide imaging in myocardial sarcoidosis. Demonstration of myocardial uptake of /sup 99m/Tc pyrophosphate and gallium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forman, M.B.; Sandler, M.P.; Sacks, G.A.

1983-03-01

A patient had severe congestive cardiomyopathy secondary to myocardial sarcoidosis. The clinical diagnosis was confirmed by radionuclide ventriculography, /sup 201/Tl, /sup 67/Ga, and /sup 99m/Tc pyrophosphate (TcPYP) scintigraphy. Myocardial TcPYP uptake has not been reported previously in sarcoidosis. In this patient, TcPYP was as useful as gallium scanning and thallium imaging in documenting the myocardial process.

Concentrations of /sup 90/Sr and /sup 137/Cs in region of discharge of warm water from the Kola Atomic Power Station

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayanov, N.I.

1982-01-01

The/sup 90/Sr and /sup 137/Cs concentrations in trout cultivated in warm water from the Kola Atomic Power Station (APS) in the period 1974-1979 were 30-70 pCi/kg. This is one-quarter to one-third of the radionuclide concentrations in wild fish living in this region and one-tenth of that in commerical fishes from other waters on the Kola Peninsula. The low radionuclide concentrations can be attributed to the absence of pollution in the coolant reservoir of the Kola APS during this period of operation, and also to the fact that the main mode of entry of radionuclides into the fish's body is throughmore » food. The investigations lead to the very important conclusion that fish-farming based on the warm effluents of atomic power stations is a feasible proposition.« less

Radionuclide demonstration of urinary extravasation with ureteral obstruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yeh, V.A.; Chiang, L.C.; Meade, R.C.

Two cases of urinary extravasation with ureteral obstruction demonstrated by the radionuclide studies are reported. The value of radionuclide studies in patients with renal transplantation has been reported previously, but studies in patients without transplantation have rarely been described in the literature. Ureteral obstruction may cause urinary extravasation, which may be demonstrated by radionuclide studies even when radiologic studies are inconclusive. In one case, urinary extravasation was detected in the sitting position but not in the supine position. Renal imaging should probably be performed not only with multiple projections but also in different positions.

Temperature Data Shows Warming in 2001

NASA Technical Reports Server (NTRS)

2002-01-01

TThe figure above depicts how much air temperatures near the Earth's surface changed relative to the global mean temperature from 1951 to 1980. NASA researchers used maps of urban areas derived from city lights data to account for the 'heat island' effect of cities. The red and orange colors show that temperatures are warmer in most regions of the world when compared to the 1951 to 1980 'normal' temperatures. Warming around the world has been widespread, but it is not present everywhere. The largest warming is in Northern Canada, Alaska and Siberia, as indicated by the deeper red colors. The lower 48 United States have become warmer recently, but only enough to make the temperatures comparable to what they were in the 1930s. The scale on the bottom of these temperature anomaly images represent degrees in Celsius. The negative numbers represent cooling and the positive numbers depict warming. Overall, the air temperature near the Earth's surface has warmed by 1oF (0.6oC) globally, on average, over the last century. For more information and additional images, read Satellites Shed Light on a Warmer World. Image courtesy Goddard Institute for Space Studies (GISS).

Radionuclide Myocardial Perfusion Imaging for the Evaluation of Patients With Known or Suspected Coronary Artery Disease in the Era of Multimodality Cardiovascular Imaging

PubMed Central

Taqueti, Viviany R.; Di Carli, Marcelo F.

2018-01-01

Over the last several decades, radionuclide myocardial perfusion imaging (MPI) with single photon emission tomography and positron emission tomography has been a mainstay for the evaluation of patients with known or suspected coronary artery disease (CAD). More recently, technical advances in separate and complementary imaging modalities including coronary computed tomography angiography, computed tomography perfusion, cardiac magnetic resonance imaging, and contrast stress echocardiography have expanded the toolbox of diagnostic testing for cardiac patients. While the growth of available technologies has heralded an exciting era of multimodality cardiovascular imaging, coordinated and dispassionate utilization of these techniques is needed to implement the right test for the right patient at the right time, a promise of “precision medicine.” In this article, we review the maturing role of MPI in the current era of multimodality cardiovascular imaging, particularly in the context of recent advances in myocardial blood flow quantitation, and as applied to the evaluation of patients with known or suspected CAD. PMID:25770849

Meeting report from the Prostate Cancer Foundation PSMA-directed radionuclide scientific working group.

PubMed

Miyahira, Andrea K; Pienta, Kenneth J; Morris, Michael J; Bander, Neil H; Baum, Richard P; Fendler, Wolfgang P; Goeckeler, William; Gorin, Michael A; Hennekes, Hartwig; Pomper, Martin G; Sartor, Oliver; Tagawa, Scott T; Williams, Scott; Soule, Howard R

2018-05-01

The Prostate Cancer Foundation (PCF) convened a PSMA-Directed Radionuclide Scientific Working Group on November 14, 2017, at Weill Cornell Medicine, New York, NY. The meeting was attended by 35 global investigators with expertise in prostate cancer biology, radionuclide therapy, molecular imaging, prostate-specific membrane antigen (PSMA)-targeted agents, drug development, and prostate cancer clinical trials. The goal of this meeting was to discuss the potential for using PSMA-targeted radionuclide agents for the treatment of advanced prostate cancer and to define the studies and clinical trials necessary for validating and optimizing the use of these agents. Several major topic areas were discussed including the overview of PSMA biology, lessons and applications of PSMA-targeted PET imaging, the nuances of designing PSMA-targeted radionuclide agents, clinical experiences with PSMA-targeted radionuclides, PCF-funded projects to accelerate PSMA-targeted radionuclide therapy, and barriers to the use of radionuclide treatments in widespread clinical practice. This article reviews the major topics discussed at the meeting with the goal of promoting research that will validate and optimize the use of PSMA-targeted radionuclide therapies for the treatment of advanced prostate cancer. © 2018 Wiley Periodicals, Inc.

Experimental Study of Nasopharyngeal Carcinoma Radionuclide Imaging and Therapy Using Transferred Human Sodium/Iodide Symporter Gene

PubMed Central

Zhong, Xing; Shi, Changzheng; Gong, Jian; Guo, Bin; Li, Mingzhu; Xu, Hao

2015-01-01

Purpose The aim of this study was to design a method of radionuclide for imaging and therapy of nasopharyngeal carcinoma (NPC) using the transferred human sodium/iodide symporter (hNIS) gene. Methods A stable NPC cell line expressing hNIS was established (CNE-2-hNIS). After 131I treatment, we detected proliferation and apoptosis of NPC cells, both in vitro and vivo. In vivo, the radioactivity of different organs of nude mice was counted and 99mTc imaging using SPECT was performed. The apparent diffusion coefficient (ADC) value changes of tumor xenografts were observed by diffusion-weighted magnetic resonance imaging (DW-MRI) within 6–24 days of 131I treatment. The correlation of ADC changes with apoptosis and proliferation was investigated. Post-treatment expression levels of P53, Bax, Bcl-2, Caspase-3, and Survivin proteins were detected by western blotting. Results 131I uptake was higher in CNE-2-hNIS than in CNE-2 cells. The proliferation and apoptosis rate decreased and increased respectively both in vitro and vivo in the experimental group after 131I treatment. The experimental group tumors accumulated 99mTc in vivo, leading to a good visualization by SPECT. DW-MRI showed that ADC values increased in the experimental group 6 days after treatment, while ADC values were positively and negatively correlated with the apoptotic and Ki-67 proliferation indices, respectively. After treatment, CNE-2-hNIS cells up-regulated the expression of P53 and Survivin proteins and activated Caspase-3, and down-regulated the expression of Bcl-2 proteins. Conclusions The radionuclide imaging and therapy technique for NPC hNIS-transfected cell lines can provide a new therapy strategy for monitoring and treatment of NPC. PMID:25615643

Diagnosis of warm dense conditions in foil targets heated by intense femtosecond laser pulses using Kα imaging spectroscopy

DOE PAGES

Bae, L. J.; Zastrau, U.; Chung, H. -K.; ...

2018-03-01

Warm dense conditions in titanium foils irradiated with intense femtosecond laser pulses are diagnosed using an x-ray imaging spectroscopy technique. The line shapes of radially resolved titanium Kα spectra are measured with a toroidally bent GaAs crystal and an x-ray charge-coupled device. Measured spectra are compared with the K-shell emissions modeled using an atomic kinetics – spectroscopy simulation code. Kα line shapes are strongly affected by warm (5-40 eV) bulk electron temperatures and imply multiple temperature distributions in the targets. Finally, the spatial distribution of temperature is dependent on the target thickness, and a thin target shows an advantage tomore » generate uniform warm dense conditions in a large area.« less

Diagnosis of warm dense conditions in foil targets heated by intense femtosecond laser pulses using Kα imaging spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bae, L. J.; Zastrau, U.; Chung, H. -K.

Warm dense conditions in titanium foils irradiated with intense femtosecond laser pulses are diagnosed using an x-ray imaging spectroscopy technique. The line shapes of radially resolved titanium Kα spectra are measured with a toroidally bent GaAs crystal and an x-ray charge-coupled device. Measured spectra are compared with the K-shell emissions modeled using an atomic kinetics – spectroscopy simulation code. Kα line shapes are strongly affected by warm (5-40 eV) bulk electron temperatures and imply multiple temperature distributions in the targets. Finally, the spatial distribution of temperature is dependent on the target thickness, and a thin target shows an advantage tomore » generate uniform warm dense conditions in a large area.« less

Radionuclide Therapy

NASA Astrophysics Data System (ADS)

Zalutsky, M. R.

Radionuclide therapy utilizes unsealed sources of radionuclides as a treatment for cancer or other pathological conditions such as rheumatoid arthritis. Radionuclides that decay by the emission of β and α particles, as well as those that emit Auger electrons, have been used for this purpose. In this chapter, radiochemical aspects of radionuclide therapy, including criteria for radionuclide selection, radionuclide production, radiolabeling chemistry, and radiation dosimetry are discussed.

Space Shuttle Video Images: An Example of Warm Cloud Lightning

NASA Technical Reports Server (NTRS)

Vaughan, Otha H., Jr.; Boeck, William L.

1998-01-01

Warm cloud lightning has been reported in several tropical locations. We have been using the intensified monochrome TV cameras at night during a number of shuttle flights to observe large active thunderstorms and their associated lightning. During a nighttime orbital pass of the STS-70 mission on 17 July 1995 at 07:57:42 GMT, the controllers obtained video imagery of a small cloud that was producing lightning. Data from a GOES infrared image establishes that the cloud top had a temperature of about 271 degrees Kelvin ( -2 degrees Celsius). Since this cloud was electrified to the extent that a lightning discharge did occur, it may be another case of lightning in a cloud that presents little if any evidence of frozen or melting precipitation.

EANM procedural guidelines for radionuclide myocardial perfusion imaging with SPECT and SPECT/CT: 2015 revision.

PubMed

Verberne, Hein J; Acampa, Wanda; Anagnostopoulos, Constantinos; Ballinger, Jim; Bengel, Frank; De Bondt, Pieter; Buechel, Ronny R; Cuocolo, Alberto; van Eck-Smit, Berthe L F; Flotats, Albert; Hacker, Marcus; Hindorf, Cecilia; Kaufmann, Philip A; Lindner, Oliver; Ljungberg, Michael; Lonsdale, Markus; Manrique, Alain; Minarik, David; Scholte, Arthur J H A; Slart, Riemer H J A; Trägårdh, Elin; de Wit, Tim C; Hesse, Birger

2015-11-01

Since the publication of the European Association of Nuclear Medicine (EANM) procedural guidelines for radionuclide myocardial perfusion imaging (MPI) in 2005, many small and some larger steps of progress have been made, improving MPI procedures. In this paper, the major changes from the updated 2015 procedural guidelines are highlighted, focusing on the important changes related to new instrumentation with improved image information and the possibility to reduce radiation exposure, which is further discussed in relation to the recent developments of new International Commission on Radiological Protection (ICRP) models. Introduction of the selective coronary vasodilator regadenoson and the use of coronary CT-contrast agents for hybrid imaging with SPECT/CT angiography are other important areas for nuclear cardiology that were not included in the previous guidelines. A large number of minor changes have been described in more detail in the fully revised version available at the EANM home page: http://eanm.org/publications/guidelines/2015_07_EANM_FINAL_myocardial_perfusion_guideline.pdf .

Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean

NASA Astrophysics Data System (ADS)

Gunn, K. L.; White, N. J.; Larter, R. D.; Caulfield, C. P.

2018-04-01

Seismic reflection images of thermohaline circulation from the Bellingshausen Sea, adjacent to the West Antarctica Peninsula, were acquired during February 2015. This survey shows that bright reflectivity occurs throughout the upper 300 m. By calibrating these seismic images with coeval hydrographic measurements, intrusion of warm water features onto the continental shelf at Marguerite and Belgica Troughs is identified and characterized. These features have distinctive lens-shaped patterns of reflectivity with lengths of 0.75-11.00 km and thicknesses of 100-150 m, suggesting that they are small mesoscale to submesoscale eddies. Abundant eddies are observed along a transect that crosses Belgica Trough. Near Alexander Island Drift, a large, of order (O)102 km3, bowl-like feature, that may represent an anticyclonic Taylor column, is imaged on a pair of orthogonal images. A modified iterative procedure is used to convert seismic imagery into maps of temperature that enable the number and size of eddies being transported onto the shelf to be quantified. Finally, analysis of prestack shot records suggests that these eddies are advecting southward at speeds of O>(0.1>) m s-1, consistent with limited legacy hydrographic measurements. Concentration of observed eddies south of the Southern Antarctic Circumpolar Current Front implies they represent both a dominant, and a long-lived, mechanism of warm-water transport, especially across Belgica Trough. Our observations suggest that previous estimates of eddy frequency may have been underestimated by up to 1 order of magnitude, which has significant implications for calculations of ice mass loss on the shelf of the West Antarctic Peninsula.

Method and apparatus for separating radionuclides from non-radionuclides

DOEpatents

Harp, Richard J.

1990-01-01

In an apparatus for separating radionuclides from non-radionuclides in a mixture of nuclear waste, a vessel is provided wherein the mixture is heated to a temperature greater than the temperature of vaporization for the non-radionuclides but less than the temperature of vaporization for the radionuclides. Consequently the non-radionuclides are vaporized while the non-radionuclides remain the solid or liquid state. The non-radionuclide vapors are withdrawn from the vessel and condensed to produce a flow of condensate. When this flow decreases the heat is reduced to prevent temperature spikes which might otherwise vaporize the radionuclides. The vessel is removed and capped with the radioactive components of the apparatus and multiple batches of the radionuclide residue disposed therein. Thus the vessel ultimately provides a burial vehicle for all of the radioactive components of the process.

Automated cassette-based production of high specific activity [203/212Pb]peptide-based theranostic radiopharmaceuticals for image-guided radionuclide therapy for cancer.

PubMed

Li, Mengshi; Zhang, Xiuli; Quinn, Thomas P; Lee, Dongyoul; Liu, Dijie; Kunkel, Falk; Zimmerman, Brian E; McAlister, Daniel; Olewein, Keith; Menda, Yusuf; Mirzadeh, Saed; Copping, Roy; Johnson, Frances L; Schultz, Michael K

2017-09-01

A method for preparation of Pb-212 and Pb-203 labeled chelator-modified peptide-based radiopharmaceuticals for cancer imaging and radionuclide therapy has been developed and adapted for automated clinical production. Pre-concentration and isolation of radioactive Pb2+ from interfering metals in dilute hydrochloric acid was optimized using a commercially-available Pb-specific chromatography resin packed in disposable plastic columns. The pre-concentrated radioactive Pb2+ is eluted in NaOAc buffer directly to the reaction vessel containing chelator-modified peptides. Radiolabeling was found to proceed efficiently at 85°C (45min; pH 5.5). The specific activity of radiolabeled conjugates was optimized by separation of radiolabeled conjugates from unlabeled peptide via HPLC. Preservation of bioactivity was confirmed by in vivo biodistribution of Pb-203 and Pb-212 labeled peptides in melanoma-tumor-bearing mice. The approach has been found to be robustly adaptable to automation and a cassette-based fluid-handling system (Modular Lab Pharm Tracer) has been customized for clinical radiopharmaceutical production. Our findings demonstrate that the Pb-203/Pb-212 combination is a promising elementally-matched radionuclide pair for image-guided radionuclide therapy for melanoma, neuroendocrine tumors, and potentially other cancers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Overview of Imaging Tests

MedlinePlus

... Overview of Imaging Tests Angiography Computed Tomography (CT) Magnetic Resonance Imaging (MRI) Plain X-Rays Radionuclide Scanning ... and radionuclide scanning Sound waves, as in ultrasonography Magnetic fields, as in magnetic resonance imaging (MRI) Substances ...

ADAPT, a Novel Scaffold Protein-Based Probe for Radionuclide Imaging of Molecular Targets That Are Expressed in Disseminated Cancers.

PubMed

Garousi, Javad; Lindbo, Sarah; Nilvebrant, Johan; Åstrand, Mikael; Buijs, Jos; Sandström, Mattias; Honarvar, Hadis; Orlova, Anna; Tolmachev, Vladimir; Hober, Sophia

2015-10-15

Small engineered scaffold proteins have attracted attention as probes for radionuclide-based molecular imaging. One class of these imaging probes, termed ABD-Derived Affinity Proteins (ADAPT), has been created using the albumin-binding domain (ABD) of streptococcal protein G as a stable protein scaffold. In this study, we report the development of a clinical lead probe termed ADAPT6 that binds HER2, an oncoprotein overexpressed in many breast cancers that serves as a theranostic biomarker for several approved targeting therapies. Surface-exposed amino acids of ABD were randomized to create a combinatorial library enabling selection of high-affinity binders to various proteins. Furthermore, ABD was engineered to enable rapid purification, to eradicate its binding to albumin, and to enable rapid blood clearance. Incorporation of a unique cysteine allowed site-specific conjugation to a maleimido derivative of a DOTA chelator, enabling radionuclide labeling, ¹¹¹In for SPECT imaging and ⁶⁸Ga for PET imaging. Pharmacologic studies in mice demonstrated that the fully engineered molecule (111)In/⁶⁸Ga-DOTA-(HE)3-ADAPT6 was specifically bound and taken up by HER2-expressing tumors, with a high tumor-to-normal tissue ratio in xenograft models of human cancer. Unbound tracer underwent rapid renal clearance followed by high renal reabsorption. HER2-expressing xenografts were visualized by gamma-camera or PET at 1 hour after infusion. PET experiments demonstrated feasibility for discrimination of xenografts with high or low HER2 expression. Our results offer a preclinical proof of concept for the use of ADAPT probes for noninvasive in vivo imaging. ©2015 American Association for Cancer Research.

Cat-scratch disease. Subtle vertebral bone marrow abnormalities demonstrated by MR imaging and radionuclide bone scan.

PubMed

Wilson, J D; Castillo, M

1995-01-01

Cat-scratch disease (CSD) is a benign, self-limited cause of lymphadenitis occurring mainly in children and young adults. Its etiology is a delicate, small gram-negative pleomorphic bacillus. Less common manifestations of CSD are seen in 5% of patients and include Parinaud's oculoglandular syndrome (with enlargement of the preauricular nodes), parotid gland enlargement, encephalitis, radiculopathy, pneumonitis, erythema nodosum, thrombocytopenia, and lytic bone lesions. We describe a patient in whom magnetic resonance imaging initially detected subtle vertebral bone marrow abnormalities that correlated with the site of abnormality on a subsequent radionuclide bone scan.

Isonitrile radionuclide complexes for labelling and imaging agents

DOEpatents

Jones, Alun G.; Davison, Alan; Abrams, Michael J.

1984-06-04

A coordination complex of an isonitrile ligand and radionuclide such as Tc, Ru, Co, Pt, Fe, Os, Ir, W, Re, Cr, Mo, Mn, Ni, Rh, Pd, Nb and Ta, is useful as a diagnostic agent for labelling liposomes or vesicles, and selected living cells containing lipid membranes, such as blood clots, myocardial tissue, gall bladder tissue, etc.

Paving the way to personalized medicine: production of some theragnostic radionuclides at Brookhaven National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Srivastava S. C.

2011-06-06

This paper introduces a relatively novel paradigm that involves specific individual radionuclides or radionuclide pairs that have emissions that allow pre-therapy low-dose imaging plus higher-dose therapy in the same patient. We have made an attempt to sort out and organize a number of such theragnostic radionuclides and radionuclide pairs that may potentially bring us closer to the age-long dream of personalized medicine for performing tailored low-dose molecular imaging (SPECT/CT or PET/CT) to provide the necessary pre-therapy information on biodistribution, dosimetry, the limiting or critical organ or tissue, and the maximum tolerated dose (MTD), etc. If the imaging results then warrantmore » it, it would be possible to perform higher-dose targeted molecular therapy in the same patient with the same radiopharmaceutical. A major problem that remains yet to be fully resolved is the lack of availability, in sufficient quantities, of a majority of the best candidate theragnostic radionuclides in a no-carrier-added (NCA) form. A brief description of the recently developed new or modified methods at BNL for the production of four theragnostic radionuclides, whose nuclear, physical, and chemical characteristics seem to show great promise for personalized cancer therapy are described.« less

Nuclear cardiology. I - Radionuclide angiographic assessment of left ventricular contraction: uses, limitations and future directions. II - The role of myocardial perfusion imaging using thallium-201 in diagnosis of coronary heart disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bodenheimer, M.M.; Banka, V.S.; Helfant, R.H.

1980-01-01

The current status of radionuclide angiography is reviewed. First pass and gated equilibrium methods for determining left ventricular contraction are compared. Some clinical applications of radionuclide angiography are then examined, including the detection of discrete versus diffuse asynergy and the assessment of myocardial infarction. The second part of this work reviews the uses and limitations of thallium-201 perfusion imaging in the diagnosis of the acute and chronic manifestations of coronary heart disease. Theoretical and technical considerations of thallium-201 imaging are reviewed along with the clinical implications of the technique.

Ion binding compounds, radionuclide complexes, methods of making radionuclide complexes, methods of extracting radionuclides, and methods of delivering radionuclides to target locations

DOEpatents

Chen, Xiaoyuan; Wai, Chien M.; Fisher, Darrell R.

2000-01-01

The invention pertains to compounds for binding lanthanide ions and actinide ions. The invention further pertains to compounds for binding radionuclides, and to methods of making radionuclide complexes. Also, the invention pertains to methods of extracting radionuclides. Additionally, the invention pertains to methods of delivering radionuclides to target locations. In one aspect, the invention includes a compound comprising: a) a calix[n]arene group, wherein n is an integer greater than 3, the calix[n]arene group comprising an upper rim and a lower rim; b) at least one ionizable group attached to the lower rim; and c) an ion selected from the group consisting of lanthanide and actinide elements bound to the ionizable group. In another aspect, the invention includes a method of extracting a radionuclide, comprising: a) providing a sample comprising a radionuclide; b) providing a calix[n]arene compound in contact with the sample, wherein n is an integer greater than 3; and c) extracting radionuclide from the sample into the calix[n]arene compound. In yet another aspect, the invention includes a method of delivering a radionuclide to a target location, comprising: a) providing a calix[n]arene compound, wherein n is an integer greater than 3, the calix[n]arene compound comprising at least one ionizable group; b) providing a radionuclide bound to the calix[n]arene compound; and c) providing an antibody attached to the calix[n]arene compound, the antibody being specific for a material found at the target location.

Methods of separating short half-life radionuclides from a mixture of radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bray, L.A.; Ryan, J.L.

1998-09-15

The present invention is a method of obtaining a radionuclide product selected from the group consisting of {sup 223}Ra and {sup 225}Ac, from a radionuclide ``cow`` of {sup 227}Ac or {sup 229}Th respectively. The method comprises the steps of (a) permitting ingrowth of at least one radionuclide daughter from said radionuclide ``cow`` forming an ingrown mixture; (b) insuring that the ingrown mixture is a nitric acid ingrown mixture; (c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the ``cow`` from at least one radionuclide daughter; (d) insuring that the at leastmore » one radionuclide daughter contains the radionuclide product; (e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and (f) recycling the at least one radionuclide daughter by adding it to the ``cow``. In one embodiment the radionuclide ``cow`` is the {sup 227}Ac, the at least one daughter radionuclide is a {sup 227}Th and the product radionuclide is the {sup 223}Ra and the first nitrate form ion exchange column passes the {sup 227}Ac and retains the {sup 227}Th. In another embodiment the radionuclide ``cow`` is the {sup 229}Th, the at least one daughter radionuclide is a {sup 225}Ra and said product radionuclide is the {sup 225}Ac and the {sup 225}Ac and nitrate form ion exchange column retains the {sup 229}Th and passes the {sup 225}Ra/Ac. 8 figs.« less

Methods of separating short half-life radionuclides from a mixture of radionuclides

DOEpatents

Bray, Lane A.; Ryan, Jack L.

1998-01-01

The present invention is a method of obtaining a radionuclide product selected from the group consisting of .sup.223 Ra and .sup.225 Ac, from a radionuclide "cow" of .sup.227 Ac or .sup.229 Th respectively. The method comprises the steps of a) permitting ingrowth of at least one radionuclide daughter from said radionuclide "cow" forming an ingrown mixture; b) insuring that the ingrown mixture is a nitric acid ingrown mixture; c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the "cow" from at least one radionuclide daughter; d) insuring that the at least one radionuclide daughter contains the radionuclide product; e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and f) recycling the at least one radionuclide daughter by adding it to the "cow". In one embodiment the radionuclide "cow" is the .sup.227 Ac, the at least one daughter radionuclide is a .sup.227 Th and the product radionuclide is the .sup.223 Ra and the first nitrate form ion exchange column passes the .sup.227 Ac and retains the .sup.227 Th. In another embodiment the radionuclide "cow"is the .sup.229 Th, the at least one daughter radionuclide is a .sup.225 Ra and said product radionuclide is the .sup.225 Ac and the .sup.225 Ac and nitrate form ion exchange column retains the .sup.229 Th and passes the .sup.225 Ra/Ac.

Methods of separating short half-life radionuclides from a mixture of radionuclides

DOEpatents

Bray, L.A.; Ryan, J.L.

1998-09-15

The present invention is a method of obtaining a radionuclide product selected from the group consisting of {sup 223}Ra and {sup 225}Ac, from a radionuclide ``cow`` of {sup 227}Ac or {sup 229}Th respectively. The method comprises the steps of (a) permitting ingrowth of at least one radionuclide daughter from said radionuclide ``cow`` forming an ingrown mixture; (b) insuring that the ingrown mixture is a nitric acid ingrown mixture; (c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the ``cow`` from at least one radionuclide daughter; (d) insuring that the at least one radionuclide daughter contains the radionuclide product; (e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and (f) recycling the at least one radionuclide daughter by adding it to the ``cow``. In one embodiment the radionuclide ``cow`` is the {sup 227}Ac, the at least one daughter radionuclide is a {sup 227}Th and the product radionuclide is the {sup 223}Ra and the first nitrate form ion exchange column passes the {sup 227}Ac and retains the {sup 227}Th. In another embodiment the radionuclide ``cow`` is the {sup 229}Th, the at least one daughter radionuclide is a {sup 225}Ra and said product radionuclide is the {sup 225}Ac and the {sup 225}Ac and nitrate form ion exchange column retains the {sup 229}Th and passes the {sup 225}Ra/Ac. 8 figs.

Quantitative Modeling of Cerenkov Light Production Efficiency from Medical Radionuclides

PubMed Central

Beattie, Bradley J.; Thorek, Daniel L. J.; Schmidtlein, Charles R.; Pentlow, Keith S.; Humm, John L.; Hielscher, Andreas H.

2012-01-01

There has been recent and growing interest in applying Cerenkov radiation (CR) for biological applications. Knowledge of the production efficiency and other characteristics of the CR produced by various radionuclides would help in accessing the feasibility of proposed applications and guide the choice of radionuclides. To generate this information we developed models of CR production efficiency based on the Frank-Tamm equation and models of CR distribution based on Monte-Carlo simulations of photon and β particle transport. All models were validated against direct measurements using multiple radionuclides and then applied to a number of radionuclides commonly used in biomedical applications. We show that two radionuclides, Ac-225 and In-111, which have been reported to produce CR in water, do not in fact produce CR directly. We also propose a simple means of using this information to calibrate high sensitivity luminescence imaging systems and show evidence suggesting that this calibration may be more accurate than methods in routine current use. PMID:22363636

MIRD Pamphlet No. 23: Quantitative SPECT for Patient-Specific 3-Dimensional Dosimetry in Internal Radionuclide Therapy

PubMed Central

Dewaraja, Yuni K.; Frey, Eric C.; Sgouros, George; Brill, A. Bertrand; Roberson, Peter; Zanzonico, Pat B.; Ljungberg, Michael

2012-01-01

In internal radionuclide therapy, a growing interest in voxel-level estimates of tissue-absorbed dose has been driven by the desire to report radiobiologic quantities that account for the biologic consequences of both spatial and temporal nonuniformities in these dose estimates. This report presents an overview of 3-dimensional SPECT methods and requirements for internal dosimetry at both regional and voxel levels. Combined SPECT/CT image-based methods are emphasized, because the CT-derived anatomic information allows one to address multiple technical factors that affect SPECT quantification while facilitating the patient-specific voxel-level dosimetry calculation itself. SPECT imaging and reconstruction techniques for quantification in radionuclide therapy are not necessarily the same as those designed to optimize diagnostic imaging quality. The current overview is intended as an introduction to an upcoming series of MIRD pamphlets with detailed radionuclide-specific recommendations intended to provide best-practice SPECT quantification–based guidance for radionuclide dosimetry. PMID:22743252

Radionuclide-fluorescence Reporter Gene Imaging to Track Tumor Progression in Rodent Tumor Models

PubMed Central

Volpe, Alessia; Man, Francis; Lim, Lindsay; Khoshnevisan, Alex; Blower, Julia; Blower, Philip J.; Fruhwirth, Gilbert O.

2018-01-01

Metastasis is responsible for most cancer deaths. Despite extensive research, the mechanistic understanding of the complex processes governing metastasis remains incomplete. In vivo models are paramount for metastasis research, but require refinement. Tracking spontaneous metastasis by non-invasive in vivo imaging is now possible, but remains challenging as it requires long-time observation and high sensitivity. We describe a longitudinal combined radionuclide and fluorescence whole-body in vivo imaging approach for tracking tumor progression and spontaneous metastasis. This reporter gene methodology employs the sodium iodide symporter (NIS) fused to a fluorescent protein (FP). Cancer cells are engineered to stably express NIS-FP followed by selection based on fluorescence-activated cell sorting. Corresponding tumor models are established in mice. NIS-FP expressing cancer cells are tracked non-invasively in vivo at the whole-body level by positron emission tomography (PET) using the NIS radiotracer [18F]BF4-. PET is currently the most sensitive in vivo imaging technology available at this scale and enables reliable and absolute quantification. Current methods either rely on large cohorts of animals that are euthanized for metastasis assessment at varying time points, or rely on barely quantifiable 2D imaging. The advantages of the described method are: (i) highly sensitive non-invasive in vivo 3D PET imaging and quantification, (ii) automated PET tracer production, (iii) a significant reduction in required animal numbers due to repeat imaging options, (iv) the acquisition of paired data from subsequent imaging sessions providing better statistical data, and (v) the intrinsic option for ex vivo confirmation of cancer cells in tissues by fluorescence microscopy or cytometry. In this protocol, we describe all steps required for routine NIS-FP-afforded non-invasive in vivo cancer cell tracking using PET/CT and ex vivo confirmation of in vivo results. This protocol has

Dual-modality imaging

NASA Astrophysics Data System (ADS)

Hasegawa, Bruce; Tang, H. Roger; Da Silva, Angela J.; Wong, Kenneth H.; Iwata, Koji; Wu, Max C.

2001-09-01

In comparison to conventional medical imaging techniques, dual-modality imaging offers the advantage of correlating anatomical information from X-ray computed tomography (CT) with functional measurements from single-photon emission computed tomography (SPECT) or with positron emission tomography (PET). The combined X-ray/radionuclide images from dual-modality imaging can help the clinician to differentiate disease from normal uptake of radiopharmaceuticals, and to improve diagnosis and staging of disease. In addition, phantom and animal studies have demonstrated that a priori structural information from CT can be used to improve quantification of tissue uptake and organ function by correcting the radionuclide data for errors due to photon attenuation, partial volume effects, scatter radiation, and other physical effects. Dual-modality imaging therefore is emerging as a method of improving the visual quality and the quantitative accuracy of radionuclide imaging for diagnosis of patients with cancer and heart disease.

Methods of increasing the performance of radionuclide generators used in nuclear medicine: daughter nuclide build-up optimisation, elution-purification-concentration integration, and effective control of radionuclidic purity.

PubMed

Le, Van So; Do, Zoe Phuc-Hien; Le, Minh Khoi; Le, Vicki; Le, Natalie Nha-Truc

2014-06-10

Methods of increasing the performance of radionuclide generators used in nuclear medicine radiotherapy and SPECT/PET imaging were developed and detailed for 99Mo/99mTc and 68Ge/68Ga radionuclide generators as the cases. Optimisation methods of the daughter nuclide build-up versus stand-by time and/or specific activity using mean progress functions were developed for increasing the performance of radionuclide generators. As a result of this optimisation, the separation of the daughter nuclide from its parent one should be performed at a defined optimal time to avoid the deterioration in specific activity of the daughter nuclide and wasting stand-by time of the generator, while the daughter nuclide yield is maintained to a reasonably high extent. A new characteristic parameter of the formation-decay kinetics of parent/daughter nuclide system was found and effectively used in the practice of the generator production and utilisation. A method of "early elution schedule" was also developed for increasing the daughter nuclide production yield and specific radioactivity, thus saving the cost of the generator and improving the quality of the daughter radionuclide solution. These newly developed optimisation methods in combination with an integrated elution-purification-concentration system of radionuclide generators recently developed is the most suitable way to operate the generator effectively on the basis of economic use and improvement of purposely suitable quality and specific activity of the produced daughter radionuclides. All these features benefit the economic use of the generator, the improved quality of labelling/scan, and the lowered cost of nuclear medicine procedure. Besides, a new method of quality control protocol set-up for post-delivery test of radionuclidic purity has been developed based on the relationship between gamma ray spectrometric detection limit, required limit of impure radionuclide activity and its measurement certainty with respect to

Functional Imaging for Prostate Cancer: Therapeutic Implications

PubMed Central

Aparici, Carina Mari; Seo, Youngho

2012-01-01

Functional radionuclide imaging modalities, now commonly combined with anatomical imaging modalities CT or MRI (SPECT/CT, PET/CT, and PET/MRI) are promising tools for the management of prostate cancer particularly for therapeutic implications. Sensitive detection capability of prostate cancer using these imaging modalities is one issue; however, the treatment of prostate cancer using the information that can be obtained from functional radionuclide imaging techniques is another challenging area. There are not many SPECT or PET radiotracers that can cover the full spectrum of the management of prostate cancer from initial detection, to staging, prognosis predictor, and all the way to treatment response assessment. However, when used appropriately, the information from functional radionuclide imaging improves, and sometimes significantly changes, the whole course of the cancer management. The limitations of using SPECT and PET radiotracers with regards to therapeutic implications are not so much different from their limitations solely for the task of detecting prostate cancer; however, the specific imaging target and how this target is reliably imaged by SPECT and PET can potentially make significant impact in the treatment of prostate cancer. Finally, while the localized prostate cancer is considered manageable, there is still significant need for improvement in noninvasive imaging of metastatic prostate cancer, in treatment guidance, and in response assessment from functional imaging including radionuclide-based techniques. In this review article, we present the rationale of using functional radionuclide imaging and the therapeutic implications for each of radionuclide imaging agent that have been studied in human subjects. PMID:22840598

Aligning physics and physiology: Engineering antibodies for radionuclide delivery.

PubMed

Tsai, Wen-Ting K; Wu, Anna M

2018-03-14

The exquisite specificity of antibodies and antibody fragments renders them excellent agents for targeted delivery of radionuclides. Radiolabeled antibodies and fragments have been successfully used for molecular imaging and radioimmunotherapy (RIT) of cell surface targets in oncology and immunology. Protein engineering has been used for antibody humanization essential for clinical applications, as well as optimization of important characteristics including pharmacokinetics, biodistribution, and clearance. Although intact antibodies have high potential as imaging and therapeutic agents, challenges include long circulation time in blood, which leads to later imaging time points post-injection and higher blood absorbed dose that may be disadvantageous for RIT. Using engineered fragments may address these challenges, as size reduction and removal of Fc function decreases serum half-life. Radiolabeled fragments and pretargeting strategies can result in high contrast images within hours to days, and a reduction of RIT toxicity in normal tissues. Additionally, fragments can be engineered to direct hepatic or renal clearance, which may be chosen based on the application and disease setting. This review discusses aligning the physical properties of radionuclides (positron, gamma, beta, alpha, and Auger emitters) with antibodies and fragments and highlights recent advances of engineered antibodies and fragments in preclinical and clinical development for imaging and therapy. Copyright © 2018 John Wiley & Sons, Ltd.

Breast imaging technology: Recent advances in imaging endogenous or transferred gene expression utilizing radionuclide technologies in living subjects - applications to breast cancer

PubMed Central

Berger, Frank; Sam Gambhir, Sanjiv

2001-01-01

A variety of imaging technologies is being investigated as tools for studying gene expression in living subjects. Two technologies that use radiolabeled isotopes are single photon emission computed tomography (SPECT) and positron emission tomography (PET). A relatively high sensitivity, a full quantitative tomographic capability, and the ability to extend small animal imaging assays directly into human applications characterize radionuclide approaches. Various radiolabeled probes (tracers) can be synthesized to target specific molecules present in breast cancer cells. These include antibodies or ligands to target cell surface receptors, substrates for intracellular enzymes, antisense oligodeoxynucleotide probes for targeting mRNA, probes for targeting intracellular receptors, and probes for genes transferred into the cell. We briefly discuss each of these imaging approaches and focus in detail on imaging reporter genes. In a PET reporter gene system for in vivo reporter gene imaging, the protein products of the reporter genes sequester positron emitting reporter probes. PET subsequently measures the PET reporter gene dependent sequestration of the PET reporter probe in living animals. We describe and review reporter gene approaches using the herpes simplex type 1 virus thymidine kinase and the dopamine type 2 receptor genes. Application of the reporter gene approach to animal models for breast cancer is discussed. Prospects for future applications of the transgene imaging technology in human gene therapy are also discussed. Both SPECT and PET provide unique opportunities to study animal models of breast cancer with direct application to human imaging. Continued development of new technology, probes and assays should help in the better understanding of basic breast cancer biology and in the improved management of breast cancer patients. PMID:11250742

Simultaneous dual-radionuclide myocardial perfusion imaging with a solid-state dedicated cardiac camera.

PubMed

Ben-Haim, Simona; Kacperski, Krzysztof; Hain, Sharon; Van Gramberg, Dean; Hutton, Brian F; Erlandsson, Kjell; Sharir, Tali; Roth, Nathaniel; Waddington, Wendy A; Berman, Daniel S; Ell, Peter J

2010-08-01

We compared simultaneous dual-radionuclide (DR) stress and rest myocardial perfusion imaging (MPI) with a novel solid-state cardiac camera and a conventional SPECT camera with separate stress and rest acquisitions. Of 27 consecutive patients recruited, 24 (64.5+/-11.8 years of age, 16 men) were injected with 74 MBq of (201)Tl (rest) and 250 MBq (99m)Tc-MIBI (stress). Conventional MPI acquisition times for stress and rest are 21 min and 16 min, respectively. Rest (201)Tl for 6 min and simultaneous DR 15-min list mode gated scans were performed on a D-SPECT cardiac scanner. In 11 patients DR D-SPECT was performed first and in 13 patients conventional stress (99m)Tc-MIBI SPECT imaging was performed followed by DR D-SPECT. The DR D-SPECT data were processed using a spill-over and scatter correction method. DR D-SPECT images were compared with rest (201)Tl D-SPECT and with conventional SPECT images by visual analysis employing the 17-segment model and a five-point scale (0 normal, 4 absent) to calculate the summed stress and rest scores. Image quality was assessed on a four-point scale (1 poor, 4 very good) and gut activity was assessed on a four-point scale (0 none, 3 high). Conventional MPI studies were abnormal at stress in 17 patients and at rest in 9 patients. In the 17 abnormal stress studies DR D-SPECT MPI showed 113 abnormal segments and conventional MPI showed 93 abnormal segments. In the nine abnormal rest studies DR D-SPECT showed 45 abnormal segments and conventional MPI showed 48 abnormal segments. The summed stress and rest scores on conventional SPECT and DR D-SPECT were highly correlated (r=0.9790 and 0.9694, respectively). The summed scores of rest (201)Tl D-SPECT and DR-DSPECT were also highly correlated (r=0.9968, p<0.0001 for all). In six patients stress perfusion defects were significantly larger on stress DR D-SPECT images, and five of these patients were imaged earlier by D-SPECT than by conventional SPECT. Fast and high-quality simultaneous DR

Identification of hip surface arthroplasty failures with TcSC/TcmDP radionuclide imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, B.J.; Amstutz, H.C.; Mai, L.L.

1982-07-01

The roentgenographic identification of femoral component loosening after hip surface arthroplasty is often impossible because the metallic femoral component obscures the bone-cement interface. The use of combined technetium sulfur colloid and technetium methylene diphosphonate radionuclide imaging has been especially useful in the diagnosis of loosening. In 40 patients, follow-up combined TcSC and TcmDP scans at an average of three, nine, and 27 months postoperation revealed significant differences in the isotope uptakes in patients who had loose prostheses compared with those without complications. Scans were evaluated by first dividing them into eight anatomical regions and then rating the uptake in eachmore » region or 'zone' on a five-point scale. Results were compared using the Student's t-test and differences were noted between normal controls and patients who had femoral component loosening. Combining both TcSC and TcmDP studies increased the statistical significance obtained when comparing patients who had complications to those in the control group.« less

The role of radionuclide imaging in the triage of patients with chest pain in the emergency department.

PubMed

Abbott, B G; Wackers, F J

2000-02-01

The triage of patients presenting to the emergency department with chest pain and a normal or nondiagnostic ECG poses a significant diagnostic challenge to emergency physicians and cardiologists, leading to unnecessary hospital admissions and substantial associated costs. Radionuclide myocardial perfusion imaging can potentially play an important role in this setting, by providing both a safe and efficient means to risk stratify patients with a low-to-moderate likelihood of unstable angina. The proposed algorithm may serve as a strategy to improve utilization of hospital resources while safely identifying the subgroup of patients with acute chest discomfort who do not need to be admitted to the hospital.

Pitfalls and Limitations of Radionuclide Planar and Hybrid Bone Imaging.

PubMed

Agrawal, Kanhaiyalal; Marafi, Fahad; Gnanasegaran, Gopinath; Van der Wall, Hans; Fogelman, Ignac

2015-09-01

The radionuclide (99m)Tc-MDP bone scan is one of the most commonly performed nuclear medicine studies and helps in the diagnosis of different pathologies relating to the musculoskeletal system. With its increasing utility in clinical practice, it becomes more important to be aware of various limitations of this imaging modality to avoid false interpretation. It is necessary to be able to recognize various technical, radiopharmaceutical, and patient-related artifacts that can occur while carrying out a bone scan. Furthermore, several normal variations of tracer uptake may mimic pathology and should be interpreted cautiously. There is an important limitation of a bone scan in metastatic disease evaluation as the inherent mechanism of tracer uptake is not specific for tumor but primarily relies on an osteoblastic response. Thus, it is crucial to keep in mind uptake in benign lesions, which can resemble malignant pathologies. The utility of a planar bone scan in benign orthopedic diseases, especially at sites with complex anatomy, is limited owing to lack of precise anatomical information. SPECT/CT has been significantly helpful in these cases. With wider use of PET/CT and reintroduction of the (18)F-fluoride bone scan, increasing knowledge of potential pitfalls on an (18)F-fluoride bone scan and (18)F-FDG-PET/CT will help in improving the accuracy of clinical reports. Copyright © 2015 Elsevier Inc. All rights reserved.

Radionuclide deposition control

DOEpatents

Brehm, William F.; McGuire, Joseph C.

1980-01-01

The deposition of radionuclides manganese-54, cobalt-58 and cobalt-60 from liquid sodium coolant is controlled by providing surfaces of nickel or high nickel alloys to extract the radionuclides from the liquid sodium, and by providing surfaces of tungsten, molybdenum or tantalum to prevent or retard radionuclide deposition.

Global Warming And Meltwater

NASA Astrophysics Data System (ADS)

Bratu, S.

2012-04-01

In order to find new approaches and new ideas for my students to appreciate the importance of science in their daily life, I proposed a theme for them to debate. They had to search for global warming information and illustrations in the media, and discuss the articles they found in the classroom. This task inspired them to search for new information about this important and timely theme in science. I informed my students that all the best information about global warming and meltwater they found would be used in a poster that would help us to update the knowledge base of the Physics laboratory. I guided them to choose the most eloquent images and significant information. Searching and working to create this poster, the students arrived to better appreciate the importance of science in their daily life and to critically evaluate scientific information transmitted via the media. In the poster we created, one can find images, photos and diagrams and some interesting information: Global warming refers to the rising average temperature of the Earth's atmosphere and oceans and its projected evolution. In the last 100 years, the Earth's average surface temperature increased by about 0.8 °C with about two thirds of the increase occurring over just the last three decades. Warming of the climate system is unequivocal, and scientists are more than 90% certain most of it is caused by increasing concentrations of greenhouse gases produced by human activities such as deforestation and burning fossil fuel. They indicate that during the 21st century the global surface temperature is likely to rise a further 1.1 to 2.9 °C for the lowest emissions scenario and 2.4 to 6.4 °C for the highest predictions. An increase in global temperature will cause sea levels to rise and will change the amount and pattern of precipitation, and potentially result in expansion of subtropical deserts. Warming is expected to be strongest in the Arctic and would be associated with continuing decrease of

Scintillating Balloon-Enabled Fiber-Optic System for Radionuclide Imaging of Atherosclerotic Plaques

PubMed Central

Zaman, Raiyan T.; Kosuge, Hisanori; Carpenter, Colin; Sun, Conroy; McConnell, Michael V.; Xing, Lei

2015-01-01

Atherosclerosis underlies coronary artery disease, the leading cause of death in the United States and worldwide. Detection of coronary plaque inflammation remains challenging. In this study, we developed a scintillating balloon-enabled fiber-optic radio-nuclide imaging (SBRI) system to improve the sensitivity and resolution of plaque imaging using 18F-FDG, a marker of vascular inflammation, and tested it in a murine model. Methods The fiber-optic system uses a Complementary Metal-Oxide Silicon (CMOS) camera with a distal ferrule terminated with a wide-angle lens. The novelty of this system is a scintillating balloon in the front of the wide-angle lens to image light from the decay of 18F-FDG emission signal. To identify the optimal scintillating materials with respect to resolution, we calculated the modulation transfer function of yttrium–aluminum–garnet doped with cerium, anthracene, and calcium fluoride doped with europium (CaF2:Eu) phosphors using an edge pattern and a thin-line optical phantom. The scintillating balloon was then fabricated from 10 mL of silicone RTV catalyst mixed with 1 mL of base and 50 mg of CaF2:Eu per mL. The addition of a lutetium oxyorthosilicate scintillating crystal (500 μm thick) to the balloon was also investigated. The SBRI system was tested in a murine atherosclerosis model: carotid-ligated mice (n = 5) were injected with 18F-FDG, followed by ex vivo imaging of the macrophage-rich carotid plaques and nonligated controls. Confirmatory imaging of carotid plaques and controls was also performed by an external optical imaging system and autoradiography. Results Analyses of the different phosphors showed that CaF2:Eu enabled the best resolution of 1.2 μm. The SBRI system detected almost a 4-fold-higher radioluminescence signal from the ligated left carotid artery than the nonligated right carotid: 1.63 × 102 ± 4.01 × 101 vs. 4.21 × 101 ± 2.09 × 100 (photon counts), P = 0.006. We found no significant benefit to adding a

Relevance of PET for pretherapeutic prediction of doses in peptide receptor radionuclide therapy.

PubMed

Blaickner, Matthias; Baum, Richard P

2014-01-01

Personalized dosimetry in radionuclide therapy has gained much attention in recent years. This attention has also an impact on peptide receptor radionuclide therapy (PRRT). This article reviews the PET-based imaging techniques that can be used for pretherapeutic prediction of doses in PRRT. More specifically the usage of (86)Y, (90)Y, (68)Ga, and (44)Sc are discussed: their characteristics for PET acquisition, the available peptides for labeling, the specifics of the imaging protocols, and the experiences gained from phantom and clinical studies. These techniques are evaluated with regard to their usefulness for dosimetry predictions in PRRT, and future perspectives are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

Ambient noise imaging in warm shallow waters; robust statistical algorithms and range estimation.

PubMed

Chitre, Mandar; Kuselan, Subash; Pallayil, Venugopalan

2012-08-01

The high frequency ambient noise in warm shallow waters is dominated by snapping shrimp. The loud snapping noises they produce are impulsive and broadband. As the noise propagates through the water, it interacts with the seabed, sea surface, and submerged objects. An array of acoustic pressure sensors can produce images of the submerged objects using this noise as the source of acoustic "illumination." This concept is called ambient noise imaging (ANI) and was demonstrated using ADONIS, an ANI camera developed at the Scripps Institution of Oceanography. To overcome some of the limitations of ADONIS, a second generation ANI camera (ROMANIS) was developed at the National University of Singapore. The acoustic time series recordings made by ROMANIS during field experiments in Singapore show that the ambient noise is well modeled by a symmetric α-stable (SαS) distribution. As high-order moments of SαS distributions generally do not converge, ANI algorithms based on low-order moments and fractiles are developed and demonstrated. By localizing nearby snaps and identifying the echoes from an object, the range to the object can be passively estimated. This technique is also demonstrated using the data collected with ROMANIS.

Dosimetric evaluation of radionuclides for VCAM-1-targeted radionuclide therapy of early brain metastases.

PubMed

Falzone, Nadia; Ackerman, Nicole L; Rosales, Liset de la Fuente; Bernal, Mario A; Liu, Xiaoxuan; Peeters, Sarah Gja; Soto, Manuel Sarmiento; Corroyer-Dulmont, Aurélien; Bernaudin, Myriam; Grimoin, Elisa; Touzani, Omar; Sibson, Nicola R; Vallis, Katherine A

2018-01-01

Brain metastases develop frequently in patients with breast cancer, and present a pressing therapeutic challenge. Expression of vascular cell adhesion molecule 1 (VCAM-1) is upregulated on brain endothelial cells during the early stages of metastasis and provides a target for the detection and treatment of early brain metastases. The aim of this study was to use a model of early brain metastasis to evaluate the efficacy of α-emitting radionuclides, 149 Tb, 211 At, 212 Pb, 213 Bi and 225 Ac; β-emitting radionuclides, 90 Y, 161 Tb and 177 Lu; and Auger electron (AE)-emitters 67 Ga, 89 Zr, 111 In and 124 I, for targeted radionuclide therapy (TRT). Histologic sections and two photon microscopy of mouse brain parenchyma were used to inform a cylindrical vessel geometry using the Geant4 general purpose Monte Carlo (MC) toolkit with the Geant4-DNA low energy physics models. Energy deposition was evaluated as a radial function and the resulting phase spaces were superimposed on a DNA model to estimate double-strand break (DSB) yields for representative β- and α-emitters, 177 Lu and 212 Pb. Relative biological effectiveness (RBE) values were determined by only evaluating DNA damage due to physical interactions. 177 Lu produced 2.69 ± 0.08 DSB per GbpGy, without significant variation from the lumen of the vessel to a radius of 100 µm. The DSB yield of 212 Pb included two local maxima produced by the 6.1 MeV and 8.8 MeV α-emissions from decay products, 212 Bi and 212 Po, with yields of 7.64 ± 0.12 and 9.15 ± 0.24 per GbpGy, respectively. Given its higher DSB yield 212 Pb may be more effective for short range targeting of early micrometastatic lesions than 177 Lu. MC simulation of a model of early brain metastases provides invaluable insight into the potential efficacy of α-, β- and AE-emitting radionuclides for TRT. 212 Pb, which has the attributes of a theranostic radionuclide since it can be used for SPECT imaging, showed a favorable dose profile and RBE.

Labeling of DOTA-conjugated HPMA-based polymers with trivalent metallic radionuclides for molecular imaging.

PubMed

Eppard, Elisabeth; de la Fuente, Ana; Mohr, Nicole; Allmeroth, Mareli; Zentel, Rudolf; Miederer, Matthias; Pektor, Stefanie; Rösch, Frank

2018-02-27

In this work, the in vitro and in vivo stabilities and the pharmacology of HPMA-made homopolymers were studied by means of radiometal-labeled derivatives. Aiming to identify the fewer amount and the optimal DOTA-linker structure that provides quantitative labeling yields, diverse DOTA-linker systems were conjugated in different amounts to HPMA homopolymers to coordinate trivalent radiometals Me(III)* = gallium-68, scandium-44, and lutetium-177. Short linkers and as low as 1.6% DOTA were enough to obtain labeling yields > 90%. Alkoxy linkers generally exhibited lower labeling yields than alkane analogues despite of similar chain length and DOTA incorporation rate. High stability of the radiolabel in all examined solutions was observed for all conjugates. Labeling with scandium-44 allowed for in vivo PET imaging and ex vivo measurements of organ distribution for up to 24 h. This study confirms the principle applicability of DOTA-HPMA conjugates for labeling with different trivalent metallic radionuclides allowing for diagnosis and therapy.

Medical Imaging.

ERIC Educational Resources Information Center

Barker, M. C. J.

1996-01-01

Discusses four main types of medical imaging (x-ray, radionuclide, ultrasound, and magnetic resonance) and considers their relative merits. Describes important recent and possible future developments in image processing. (Author/MKR)

Terra Data Confirm Warm, Dry U.S. Winter

NASA Technical Reports Server (NTRS)

2002-01-01

New maps of land surface temperature and snow cover produced by NASA's Terra satellite show this year's winter was warmer than last year's, and the snow line stayed farther north than normal. The observations confirm earlier National Oceanic and Atmospheric Administration reports that the United States was unusually warm and dry this past winter. (Click to read the NASA press release and to access higher-resolution images.) For the last two years, a new sensor aboard Terra has been collecting the most detailed global measurements ever made of our world's land surface temperatures and snow cover. The Moderate-resolution Imaging Spectroradiometer (MODIS) is already giving scientists new insights into our changing planet. Average temperatures during December 2001 through February 2002 for the contiguous United States appear to have been unseasonably warm from the Rockies eastward. In the top image the coldest temperatures appear black, while dark green, blue, red, yellow, and white indicate progressively warmer temperatures. MODIS observes both land surface temperature and emissivity, which indicates how efficiently a surface absorbs and emits thermal radiation. Compared to the winter of 2000-01, temperatures throughout much of the U.S. were warmer in 2001-02. The bottom image depicts the differences on a scale from dark blue (colder this year than last) to red (warmer this year than last). A large region of warm temperatures dominated the northern Great Plains, while the area around the Great Salt Lake was a cold spot. Images courtesy Robert Simmon, NASA GSFC, based upon data courtesy Zhengming Wan, MODIS Land Science Team member at the University of California, Santa Barbara's Institute for Computational Earth System Science

Direct Imaging of Warm Extrasolar Planets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Macintosh, B

2005-04-11

One of the most exciting scientific discoveries in the last decade of the twentieth century was the first detection of planets orbiting a star other than our own. By now more than 130 extrasolar planets have been discovered indirectly, by observing the gravitational effects of the planet on the radial velocity of its parent star. This technique has fundamental limitations: it is most sensitive to planets close to their star, and it determines only a planet's orbital period and a lower limit on the planet's mass. As a result, all the planetary systems found so far are very different frommore » our own--they have giant Jupiter-sized planets orbiting close to their star, where the terrestrial planets are found in our solar system. Such systems have overturned the conventional paradigm of planet formation, but have no room in them for habitable Earth-like planets. A powerful complement to radial velocity detections of extrasolar planets will be direct imaging--seeing photons from the planet itself. Such a detection would allow photometric measurements to determine the temperature and radius of a planet. Also, direct detection is most sensitive to planets in wide orbits, and hence more capable of seeing solar systems resembling our own, since a giant planet in a wide orbit does not preclude the presence of an Earth-like planet closer to the star. Direct detection, however, is extremely challenging. Jupiter is roughly a billion times fainter than our sun. Two techniques allowed us to overcome this formidable contrast and attempt to see giant planets directly. The first is adaptive optics (AO) which allows giant earth-based telescopes, such as the 10 meter W.M. Keck telescope, to partially overcome the blurring effects of atmospheric turbulence. The second is looking for young planets: by searching in the infrared for companions to young stars, we can see thermal emission from planets that are still warm with the heat of their formation. Together with a UCLA team that

Europa Plumes Located near Warm Spot on Europa

NASA Image and Video Library

2017-04-13

These images of the surface of the Jovian moon Europa, taken by NASA's Galileo spacecraft, focus on a "region of interest" on the icy moon. The image at left traces the location of the erupting plumes of material, observed by NASA's Hubble Space Telescope in 2014 and again in 2016. The plumes are located inside the area surrounded by the green oval. The green oval also corresponds to a warm region on Europa's surface, as identified by the temperature map at right. The map is based on observations by the Galileo spacecraft. The warmest area is colored bright red. Researchers speculate these data offer circumstantial evidence for unusual activity that may be related to a subsurface ocean on Europa. The dark circle just below center in both images is a crater and is not thought to be related to the warm spot or the plume activity. https://photojournal.jpl.nasa.gov/catalog/PIA21444

Observation-based estimate of the Fukushima radionuclide in the North Pacific

NASA Astrophysics Data System (ADS)

Yoshida, Sachiko; Jayne, Steven; Macdonald, Alison; Buesseler, Ken; Rypina, Irina

2014-05-01

Contaminated waters from Fukushima nuclear power plant (FNPP) were discharged directly into the North Pacific Ocean in March 2011. Coastal current system in this region and time scale of the water exchange with the open ocean is not well understood, however both observational evidence and numerical model simulation results indicate relatively rapid advection of contaminants eastward into the highly energetic mixed water region in the confluence of the Kuroshio and Oyashio. Surface drifters deployed near the FNPP in early summer 2011 show trajectories crossing the North Pacific generally following the large scale ocean circulation after one year. Previously obtained cesium (Cs) samples from multiple cruises near FNPP and off shore region between 2011 and 2013 are collected and evaluated to diagnose the propagating Cs signal crossing North Pacific Ocean. In this presentation, we use radionuclides of Fukushima origin as a tracer to understand the North Pacific circulation and mixing process after two years of release. Large numbers of the observation are repeatedly took place near shore where Cs shows still relatively higher about 10-30 Bq/m3 in 2013. Temperature-salinity (T-S) properties for the available hydrographic data indicate that the majority of the samples were obtained in the region where the water is highly influenced by the warm-salty Kuroshio origin water. Depth profiles of 35N section in March-May 2013 cruise of the U.S. Climate Variability and Predictability and Carbon (CLIVAR) repeat Hydrography sections are examined to track the radionuclide penetration into the subsurface ocean and the subduction pathways along isopycnal surfaces. Available large drifter datasets that accumulated over decades of field work can guide us in estimating the spread of these radionuclides. By applying an innovative statistical analysis to the drifter data, we investigate the spreading of radionuclides in the Pacific Ocean over 5-year time scales.

Radionuclide removal by apatite

DOE PAGES

Rigali, Mark J.; Brady, Patrick V.; Moore, Robert C.

2016-12-01

In this study, a growing body of research supports widespread future reliance on apatite for radioactive waste cleanup. Apatite is a multi-functional radionuclide sorbent that lowers dissolved radionuclide concentrations by surface sorption, ion exchange, surface precipitation, and by providing phosphate to precipitate low-solubility radionuclide-containing minerals. Natural apatites are rich in trace elements, and apatite’s stability in the geologic record suggest that radionuclides incorporated into apatite, whether in a permeable reactive barrier or a waste form, are likely to remain isolated from the biosphere for long periods of time. Here we outline the mineralogic and surface origins of apatite-radionuclide reactivity andmore » show how apatites might be used to environmental advantage in the future.« less

Single photon emission computed tomography/positron emission tomography imaging and targeted radionuclide therapy of melanoma: new multimodal fluorinated and iodinated radiotracers.

PubMed

Maisonial, Aurélie; Kuhnast, Bertrand; Papon, Janine; Boisgard, Raphaël; Bayle, Martine; Vidal, Aurélien; Auzeloux, Philippe; Rbah, Latifa; Bonnet-Duquennoy, Mathilde; Miot-Noirault, Elisabeth; Galmier, Marie-Josèphe; Borel, Michèle; Askienazy, Serge; Dollé, Frédéric; Tavitian, Bertrand; Madelmont, Jean-Claude; Moins, Nicole; Chezal, Jean-Michel

2011-04-28

This study reports a series of 14 new iodinated and fluorinated compounds offering both early imaging ((123)I, (124)I, (18)F) and systemic treatment ((131)I) of melanoma potentialities. The biodistribution of each (125)I-labeled tracer was evaluated in a model of melanoma B16F0-bearing mice, using in vivo serial γ scintigraphic imaging. Among this series, [(125)I]56 emerged as the most promising compound in terms of specific tumoral uptake and in vivo kinetic profile. To validate our multimodality concept, the radiosynthesis of [(18)F]56 was then optimized and this radiotracer has been successfully investigated for in vivo PET imaging of melanoma in B16F0- and B16F10-bearing mouse model. The therapeutic efficacy of [(131)I]56 was then evaluated in mice bearing subcutaneous B16F0 melanoma, and a significant slow down in tumoral growth was demonstrated. These data support further development of 56 for PET imaging ((18)F, (124)I) and targeted radionuclide therapy ((131)I) of melanoma using a single chemical structure.

Radionuclide diagnosis of splenic rupture in infectious mononucleosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vezina, W.C.; Nicholson, R.L.; Cohen, P.

1984-06-01

Spontaneous splenic rupture is a rare but serious complication of infectious mononucleosis. Although radionuclide spleen imaging is a well accepted method for diagnosis of traumatic rupture, interpretation can be difficult in the setting of mononucleosis, as tears may be ill-defined and diagnosis hampered by inhomogeneous splenic uptake. Four proven cases of spontaneous rupture are presented, three of which illustrate these diagnostic problems.

Radionuclides in radiation-induced bystander effect; may it share in radionuclide therapy?

PubMed

Widel, M

2017-01-01

For many years in radiobiology and radiotherapy predominated the conviction that cellular DNA is the main target for ionizing radiation, however, the view has changed in the past 20 years. Nowadays, it is assumed that not only directed (targeted) radiation effect, but also an indirect (non-targeted) effect may contribute to the result of radiation treatment. Non-targeted effect is relatively well recognized after external beam irradiation in vitro and in vivo, and comprises such phenomena like radiation-induced bystander effect (RIBE), genomic instability, adaptive response and abscopal (out of field) effect. These stress-induced and molecular signaling mediated phenomena appear in non-targeted cells as variety responses resembling that observed in directly hit cells. Bystander effects can be both detrimental and beneficial in dependence on dose, dose-rate, cell type, genetic status and experimental condition. Less is known about radionuclide-induced non-targeted effects in radionuclide therapy, although, based on characteristics of the radionuclide radiation, on experiments in vitro utilizing classical and 3-D cell cultures, and preclinical study on animals it seems obvious that exposure to radionuclide is accompanied by various bystander effects, mostly damaging, less often protective. This review summarizes existing data on radionuclide induced bystander effects comprising radionuclides emitting beta- and alpha-particles and Auger electrons used in tumor radiotherapy and diagnostics. So far, separation of the direct effect of radionuclide decay from crossfire and bystander effects in clinical targeted radionuclide therapy is impossible because of the lack of methods to assess whether, and to what extent bystander effect is involved in human organism. Considerations on this topic are also included.

Innovations in Nuclear Imaging Instrumentation: Cerenkov Imaging.

PubMed

Tamura, Ryo; Pratt, Edwin C; Grimm, Jan

2018-07-01

Cerenkov luminescence (CL) is blue glow light produced by charged subatomic particles travelling faster than the phase velocity of light in a dielectric medium such as water or tissue. CL was first discovered in 1934, but for biomedical research it was recognized only in 2009 after advances in optical camera sensors brought the required high sensitivity. Recently, applications of CL from clinical radionuclides have been rapidly expanding to include not only preclinical and clinical biomedical imaging but also an approach to therapy. Cerenkov Luminescence Imaging (CLI) utilizes CL generated from clinically relevant radionuclides alongside optical imaging instrumentation. CLI is advantageous over traditional nuclear imaging methods in terms of infrastructure cost, resolution, and imaging time. Furthermore, CLI is a truly multimodal imaging method where the same agent can be detected by two independent modalities, with optical (CL) imaging and with positron emission tomography (PET) imaging. CL has been combined with small molecules, biomolecules and nanoparticles to improve diagnosis and therapy in cancer research. Here, we cover the fundamental breakthroughs and recent advances in reagents and instrumentation methods for CLI as well as therapeutic application of CL. Copyright © 2018 Elsevier Inc. All rights reserved.

PSMA PET and radionuclide therapy in prostate cancer

PubMed Central

Bouchelouche, Kirsten; Turkbey, Baris; Choyke, Peter L.

2016-01-01

Prostate cancer (Pca) is the most common malignancy in men and a major cause of cancer death. Accurate imaging plays an important role in diagnosis, staging, restaging, detection of biochemical recurrence, and for therapy of PCa patients. Since no effective treatment is available for advanced PCa, there is an urgent need to develop new and more effective therapeutic strategies. In order to optimize treatment outcome, especially in high risk PCa patients, therapy of PCa is moving rapidly towards personalization. Medical imaging, including positron emission tomography (PET)/computed tomography (CT), plays an important role in personalized medicine in oncology. In the recent years, much focus has been on prostate specific membrane antigen (PSMA) as a promising target for imaging and therapy with radionuclides, since it is upregulated in most PCa. In the prostate, one potential role for PSMA PET imaging is to help guiding focal therapy. Several studies have shown great potential of PSMA PET/CT for initial staging, lymph node staging, and detection of recurrence of PCa, even at very low PSA values after primary therapy. Furthermore, studies have shown that PSMA PET/CT has a higher detection rate than choline PET/CT. Radiolabeled PSMA ligands for therapy show promise in several studies with metastatic PCa, and is an area of active investigation. The “Image and treat” strategy, with radiolabeled PSMA ligands, has the potential to improve the treatment outcome of PCa patients, and is paving the way for precision medicine in PCa. The aim of this review is to give an overview of recent advancement in PSMA PET and radionuclide therapy of PCa. PMID:27825432

Reactor-Produced Medical Radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mirzadeh, Saed; Mausner, Leonard; Garland, Marc A

2011-01-01

The therapeutic use of radionuclides in nuclear medicine, oncology and cardiology is the most rapidly growing use of medical radionuclides. Since most therapeutic radionuclides are neutron rich and decay by beta emission, they are reactor-produced. This chapter deals mainly with production approaches with neutrons. Neutron interactions with matter, neutron transmission and activation rates, and neutron spectra of nuclear reactors are discussed in some detail. Further, a short discussion of the neutron-energy dependence of cross sections, reaction rates in thermal reactors, cross section measurements and flux monitoring, and general equations governing the reactor production of radionuclides are presented. Finally, the chaptermore » is concluded by providing a number of examples encompassing the various possible reaction routes for production of a number of medical radionuclides in a reactor.« less

Imaging, biodistribution, and dosimetry of radionuclide-labeled PD-L1 antibody in an immunocompetent mouse model of breast cancer

PubMed Central

Josefsson, Anders; Nedrow, Jessie R.; Park, Sunju; Banerjee, Sangeeta Ray; Rittenbach, Andrew; Jammes, Fabien; Tsui, Benjamin; Sgouros, George

2015-01-01

The programmed cell death ligand 1 (PD-L1) participates in an immune checkpoint system involved in preventing autoimmunity. PD-L1 is expressed on tumor cells, tumor-associated macrophages, and other cells in the tumor microenvironment. Anti-PD-L1 antibodies are active against a variety of cancers, and combined anti-PD-L1 therapy with external beam radiotherapy has been shown to increase therapeutic efficacy. PD-L1 expression status is an important indicator of prognosis and therapy responsiveness, but methods to precisely capture the dynamics of PD-L1 expression in the tumor microenvironment are still limited. In this study, we developed a murine anti-PD-L1 antibody conjugated to the radioactive isotope Indium-111 (111In) for imaging and biodistribution studies in an immune-intact mouse model of breast cancer. The distribution of 111In-DTPA-anti-PD-L1 in tumors as well as the spleen, liver, thymus, heart, and lungs peaked 72 hours after injection. Co-injection of labeled and 100-fold unlabeled antibody significantly reduced spleen uptake at 24 hours, indicating that an excess of unlabeled antibody effectively blocked PD-L1 sites in the spleen, thus shifting the concentration of 111In-DTPA-anti-PD-L1 into the blood stream and potentially increasing tumor uptake. Clearance of 111In-DTPA-anti-PD-L1 from all organs occurred at 144 hours. Moreover, dosimetry calculations revealed that radionuclide-labeled anti-PD-L1 antibody yielded tolerable projected marrow doses, further supporting its use for radiopharmaceutical therapy. Taken together, these studies demonstrate the feasibility of using anti-PD-L1 antibody for radionuclide imaging and radioimmunotherapy, and highlight a new opportunity to optimize and monitor the efficacy of immune checkpoint inhibition therapy. PMID:26554829

Radionuclide detection devices and associated methods

DOEpatents

Mann, Nicholas R [Rigby, ID; Lister, Tedd E [Idaho Falls, ID; Tranter, Troy J [Idaho Falls, ID

2011-03-08

Radionuclide detection devices comprise a fluid cell comprising a flow channel for a fluid stream. A radionuclide collector is positioned within the flow channel and configured to concentrate one or more radionuclides from the fluid stream onto at least a portion of the radionuclide collector. A scintillator for generating scintillation pulses responsive to an occurrence of a decay event is positioned proximate at least a portion of the radionuclide collector and adjacent to a detection system for detecting the scintillation pulses. Methods of selectively detecting a radionuclide are also provided.

Radionuclide Imaging of Musculoskeletal Injuries in Athletes with Negative Radiographs.

PubMed

Nagle, C E; Freitas, J E

1987-06-01

In brief: Radionuclide bone scans can be useful in the diagnostic evaluation of musculoskeletal injuries in athletes. Bone scans can detect shinsplints, stress fractures, and muscle injuries before they are detectable on radiographs. Prognosis can be accurately assessed, allowing appropriate treatment to proceed without delay. The authors discuss the use of bone scans and identify musculoskeletal injuries that are associated with specific sports, such as stress fracture of the femur (soccer), tibia (running), scapula (gymnastics), and pars interarticularis (football or lacrosse).

Single photon emission computed tomography imaging for temporal dynamics of thyroidal and salivary radionuclide accumulation in 17-allyamino-17-demothoxygeldanamycin-treated thyroid cancer mouse model

PubMed Central

Liu, Yu-Yu; Brandt, Michael P; Shen, Daniel H; Kloos, Richard T; Zhang, Xiaoli; Jhiang, Sissy M

2014-01-01

Selective iodide uptake and prolonged iodine retention in the thyroid is the basis for targeted radioiodine therapy for thyroid cancer patients; however, salivary gland dysfunction is the most frequent nonthyroidal complications. In this study, we have used noninvasive single photon emission computed tomography functional imaging to quantify the temporal dynamics of thyroidal and salivary radioiodine accumulation in mice. At 60 min post radionuclide injection, radionuclide accumulation in the salivary gland was generally higher than that in thyroid due to much larger volume of the salivary gland. However, radionuclide accumulation per anatomic unit in the salivary gland was lower than that in thyroid and was comparable among mice of different age and gender. Differently, radionuclide accumulation per anatomic unit in thyroid varied greatly among mice. The extent of thyroidal radioiodine accumulation stimulated by a single dose of exogenous bovine TSH (bTSH) in triiodothyronine (T3)-supplemented mice was much less than that in mice received neither bTSH nor T3 (nontreated mice), suggesting that the duration of elevated serum TSH level is important to maximize thyroidal radioiodine accumulation. Furthermore, the extent and duration of radioiodine accumulation stimulated by bTSH was less in the thyroids of the thyroid-targeted RET/PTC1 (thyroglobulin (Tg)-PTC1) mice bearing thyroid tumors compared with the thyroids in wild-type (WT) mice. Finally, the effect of 17-allyamino-17-demothoxygeldanamycin on increasing thyroidal, but not salivary, radioiodine accumulation was validated in both WT mice and Tg-PTC1 preclinical thyroid cancer mouse model. PMID:20943721

Optical Imaging of Ionizing Radiation from Clinical Sources.

PubMed

Shaffer, Travis M; Drain, Charles Michael; Grimm, Jan

2016-11-01

Nuclear medicine uses ionizing radiation for both in vivo diagnosis and therapy. Ionizing radiation comes from a variety of sources, including x-rays, beam therapy, brachytherapy, and various injected radionuclides. Although PET and SPECT remain clinical mainstays, optical readouts of ionizing radiation offer numerous benefits and complement these standard techniques. Furthermore, for ionizing radiation sources that cannot be imaged using these standard techniques, optical imaging offers a unique imaging alternative. This article reviews optical imaging of both radionuclide- and beam-based ionizing radiation from high-energy photons and charged particles through mechanisms including radioluminescence, Cerenkov luminescence, and scintillation. Therapeutically, these visible photons have been combined with photodynamic therapeutic agents preclinically for increasing therapeutic response at depths difficult to reach with external light sources. Last, new microscopy methods that allow single-cell optical imaging of radionuclides are reviewed. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Cerenkov imaging - a new modality for molecular imaging

PubMed Central

Thorek, Daniel LJ; Robertson, Robbie; Bacchus, Wassifa A; Hahn, Jaeseung; Rothberg, Julie; Beattie, Bradley J; Grimm, Jan

2012-01-01

Cerenkov luminescence imaging (CLI) is an emerging hybrid modality that utilizes the light emission from many commonly used medical isotopes. Cerenkov radiation (CR) is produced when charged particles travel through a dielectric medium faster than the speed of light in that medium. First described in detail nearly 100 years ago, CR has only recently applied for biomedical imaging purposes. The modality is of considerable interest as it enables the use of widespread luminescence imaging equipment to visualize clinical diagnostic (all PET radioisotopes) and many therapeutic radionuclides. The amount of light detected in CLI applications is significantly lower than other that in other optical imaging techniques such as bioluminescence and fluorescence. However, significant advantages include the use of approved radiotracers and lack of an incident light source, resulting in high signal to background ratios. As well, multiple subjects may be imaged concurrently (up to 5 in common bioluminescent equipment), conferring both cost and time benefits. This review summarizes the field of Cerenkov luminescence imaging to date. Applications of CLI discussed include intraoperative radionuclide-guided surgery, monitoring of therapeutic efficacy, tomographic optical imaging capabilities, and the ability to perform multiplexed imaging using fluorophores excited by the Cerenkov radiation. While technical challenges still exist, Cerenkov imaging has materialized as an important molecular imaging modality. PMID:23133811

Optical Imaging of Ionizing Radiation from Clinical Sources

PubMed Central

Shaffer, Travis M.; Drain, Charles Michael

2016-01-01

Nuclear medicine uses ionizing radiation for both in vivo diagnosis and therapy. Ionizing radiation comes from a variety of sources, including x-rays, beam therapy, brachytherapy, and various injected radionuclides. Although PET and SPECT remain clinical mainstays, optical readouts of ionizing radiation offer numerous benefits and complement these standard techniques. Furthermore, for ionizing radiation sources that cannot be imaged using these standard techniques, optical imaging offers a unique imaging alternative. This article reviews optical imaging of both radionuclide- and beam-based ionizing radiation from high-energy photons and charged particles through mechanisms including radioluminescence, Cerenkov luminescence, and scintillation. Therapeutically, these visible photons have been combined with photodynamic therapeutic agents preclinically for increasing therapeutic response at depths difficult to reach with external light sources. Last, new microscopy methods that allow single-cell optical imaging of radionuclides are reviewed. PMID:27688469

Automated method and system for the alignment and correlation of images from two different modalities

DOEpatents

Giger, Maryellen L.; Chen, Chin-Tu; Armato, Samuel; Doi, Kunio

1999-10-26

A method and system for the computerized registration of radionuclide images with radiographic images, including generating image data from radiographic and radionuclide images of the thorax. Techniques include contouring the lung regions in each type of chest image, scaling and registration of the contours based on location of lung apices, and superimposition after appropriate shifting of the images. Specific applications are given for the automated registration of radionuclide lungs scans with chest radiographs. The method in the example given yields a system that spatially registers and correlates digitized chest radiographs with V/Q scans in order to correlate V/Q functional information with the greater structural detail of chest radiographs. Final output could be the computer-determined contours from each type of image superimposed on any of the original images, or superimposition of the radionuclide image data, which contains high activity, onto the radiographic chest image.

Amplified Arctic warming by phytoplankton under greenhouse warming.

PubMed

Park, Jong-Yeon; Kug, Jong-Seong; Bader, Jürgen; Rolph, Rebecca; Kwon, Minho

2015-05-12

Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical-ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean-atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes.

Amplified Arctic warming by phytoplankton under greenhouse warming

PubMed Central

Park, Jong-Yeon; Kug, Jong-Seong; Bader, Jürgen; Rolph, Rebecca; Kwon, Minho

2015-01-01

Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical–ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean−atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes. PMID:25902494

On-Orbit Solar Dynamics Observatory (SDO) Star Tracker Warm Pixel Analysis

NASA Technical Reports Server (NTRS)

Felikson, Denis; Ekinci, Matthew; Hashmall, Joseph A.; Vess, Melissa

2011-01-01

This paper describes the process of identification and analysis of warm pixels in two autonomous star trackers on the Solar Dynamics Observatory (SDO) mission. A brief description of the mission orbit and attitude regimes is discussed and pertinent star tracker hardware specifications are given. Warm pixels are defined and the Quality Index parameter is introduced, which can be explained qualitatively as a manifestation of a possible warm pixel event. A description of the algorithm used to identify warm pixel candidates is given. Finally, analysis of dumps of on-orbit star tracker charge coupled devices (CCD) images is presented and an operational plan going forward is discussed. SDO, launched on February 11, 2010, is operated from the NASA Goddard Space Flight Center (GSFC). SDO is in a geosynchronous orbit with a 28.5 inclination. The nominal mission attitude points the spacecraft X-axis at the Sun, with the spacecraft Z-axis roughly aligned with the Solar North Pole. The spacecraft Y-axis completes the triad. In attitude, SDO moves approximately 0.04 per hour, mostly about the spacecraft Z-axis. The SDO star trackers, manufactured by Galileo Avionica, project the images of stars in their 16.4deg x 16.4deg fields-of-view onto CCD detectors consisting of 512 x 512 pixels. The trackers autonomously identify the star patterns and provide an attitude estimate. Each unit is able to track up to 9 stars. Additionally, each tracker calculates a parameter called the Quality Index, which is a measure of the quality of the attitude solution. Each pixel in the CCD measures the intensity of light and a warns pixel is defined as having a measurement consistently and significantly higher than the mean background intensity level. A warns pixel should also have lower intensity than a pixel containing a star image and will not move across the field of view as the attitude changes (as would a dim star image). It should be noted that the maximum error introduced in the star tracker

49 CFR 173.433 - Requirements for determining basic radionuclide values, and for the listing of radionuclides on...

Code of Federal Regulations, 2010 CFR

2010-10-01

... radionuclide values, and for the listing of radionuclides on shipping papers and labels. (a) For individual... given in the table in § 173.436. (b) For individual radionuclides which are not listed in the tables in.... (d) Mixtures of radionuclides whose identities and respective activities are known must conform to...

49 CFR 173.433 - Requirements for determining basic radionuclide values, and for the listing of radionuclides on...

Code of Federal Regulations, 2011 CFR

2011-10-01

... radionuclide values, and for the listing of radionuclides on shipping papers and labels. (a) For individual... given in the table in § 173.436. (b) For individual radionuclides which are not listed in the tables in.... (d) Mixtures of radionuclides whose identities and respective activities are known must conform to...

49 CFR 173.433 - Requirements for determining basic radionuclide values, and for the listing of radionuclides on...

Code of Federal Regulations, 2013 CFR

2013-10-01

... radionuclide values, and for the listing of radionuclides on shipping papers and labels. (a) For individual... given in the table in § 173.436. (b) For individual radionuclides which are not listed in the tables in.... (d) Mixtures of radionuclides whose identities and respective activities are known must conform to...

49 CFR 173.433 - Requirements for determining basic radionuclide values, and for the listing of radionuclides on...

Code of Federal Regulations, 2012 CFR

2012-10-01

... radionuclide values, and for the listing of radionuclides on shipping papers and labels. (a) For individual... given in the table in § 173.436. (b) For individual radionuclides which are not listed in the tables in.... (d) Mixtures of radionuclides whose identities and respective activities are known must conform to...

Ventilation and perfusion imaging by electrical impedance tomography: a comparison with radionuclide scanning.

PubMed

Kunst, P W; Vonk Noordegraaf, A; Hoekstra, O S; Postmus, P E; de Vries, P M

1998-11-01

Electrical impedance tomography (EIT) is a technique that makes it possible to measure ventilation and pulmonary perfusion in a volume that approximates to a 2D plane. The possibility of using EIT for measuring the left-right division of ventilation and perfusion was compared with that of radionuclide imaging. Following routine ventilation (81mKr) and perfusion scanning (99mTc-MAA), EIT measurements were performed at the third and the sixth intercostal level in 14 patients with lung cancer. A correlation (r = 0.98, p < 0.005) between the left-right division for the ventilation measured with EIT and that with 81mKr was found. For the left-right division of pulmonary perfusion a correlation of 0.95 (p < 0.005) was found between the two methods. The reliability coefficient (RC) was calculated for estimating the left-right division with EIT. The RC for the ventilation measurements was 94% and 96% for the perfusion measurements. The correlation analysis for reproducibility of the EIT measurements was 0.95 (p < 0.001) for the ventilation and 0.93 (p < 0.001) for the perfusion measurements. In conclusion, EIT can be regarded as a promising technique to estimate the left-right division of pulmonary perfusion and ventilation.

Improving cancer treatment with cyclotron produced radionuclides. Comprehensive progress report, February 1, 1992--July 15, 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Larson, S.M.; Finn, R.D.

1995-07-17

This research continues the long term goals of promoting nuclear medicine applications by improving the scientific basis for tumor diagnosis, treatment and treatment follow-up based on the use of cyclotron produced radiotracers in oncology. This program fits into the nuclear medicine component of DOE`s mission, which is aimed at enhancing the beneficial applications of radiation, radionuclides, and stable isotopes in the diagnosis, study and treatment of human diseases. The grant includes 3 interactive components: Radiochemistry/Cyclotron; Pharmacology/Immunology; and Imaging Physics. An essential strategy is as follows: novel radionuclides and radiotracers developed in the Radiochemistry/Section under the DOE grant during the 1992--1995more » will be employed in the Pharmacology/Immunology component in the period 1996--1999. Imaging Physics resolves relevant imaging related physics issues that arise during the experimentation that results. In addition to the basic research mission, this project also provides a basis for training of research scientists in radiochemistry, immunology, bioengineering and imaging physics.« less

Transfer of fallout radionuclides derived from Fukushima NPP accident: 1 year study on transfer of radionuclides through geomorphic processes

NASA Astrophysics Data System (ADS)

Onda, Y.; Kato, H.; Fukushima, T.; Wakahara, T.; Kita, K.; Takahashi, Y.; Sakaguchi, A.; Tanaka, K.; Yamashiki, Y.; Yoshida, N.

2012-12-01

After the Fukushima Daiichi Nuclear Power Plant acciden, fallout radionuclides on the ground surface will transfer through geomorphic processes. Therefore, in order to estimate future changes in radionuclide deposition, migration process of radionuclides in forests, soils, ground water, rivers, and entrainment from trees and soils should be confirmed. We (FMWSE group) was funded by MEXT, Japanese government, and 1 year following monitoring has been conducted about 1 year. 1 Migration study of radionuclides in natural environment including forests and rivers 1) Study on depth distribution of radiocaesium in soils within forests, fields, and grassland. 2) Confirmation of radionuclide distribution and investigation on migration in forests. 3) Study on radionuclide migration due to soil erosion under different land use. 4) Measurement of radionuclides entrained from natural environment including forests and soils. 2 Migration study of radionuclides through hydrological cycle such as soil water, rivers, lakes and ponds, ground water. 1) Investigation on radionuclide migration through soil water, ground water, stream water, spring water under different land use. 2) Study on paddy-to-river transfer of radionuclides through suspended sediment. 3) Study on river-to-ocean transfer of radionuclides via suspended sediment. 4) Confirmation of radionuclide deposition in ponds and reservoirs. We will present how and where the fallout radionulides transfter through geomorphic processes.

Radioactivity and the environment: technical approaches to understand the role of arbuscular mycorrhizal plants in radionuclide bioaccumulation

PubMed Central

Davies, Helena S.; Cox, Filipa; Robinson, Clare H.; Pittman, Jon K.

2015-01-01

Phytoaccumulation of radionuclides is of significant interest with regards to monitoring radionuclide build-up in food chains, developing methods for environmental bioremediation and for ecological management. There are many gaps in our understanding of the characteristics and mechanisms of plant radionuclide accumulation, including the importance of symbiotically-associated arbuscular mycorrhizal (AM) fungi. We first briefly review the evidence that demonstrates the ability of AM fungi to enhance the translocation of 238U into plant root tissues, and how fungal association may prevent further mobilization into shoot tissues. We then focus on approaches that should further advance our knowledge of AM fungi–plant radionuclide accumulation. Current research has mostly used artificial cultivation methods and we consider how more ecologically-relevant analysis might be performed. The use of synchrotron-based X-ray fluorescence imaging and absorption spectroscopy techniques to understand the mechanisms of radionuclide transfer from soil to plant via AM fungi is evaluated. Without such further knowledge, the behavior and mobilization of radionuclides cannot be accurately modeled and the potential risks cannot be accurately predicted. PMID:26284096

Radioactivity and the environment: technical approaches to understand the role of arbuscular mycorrhizal plants in radionuclide bioaccumulation.

PubMed

Davies, Helena S; Cox, Filipa; Robinson, Clare H; Pittman, Jon K

2015-01-01

Phytoaccumulation of radionuclides is of significant interest with regards to monitoring radionuclide build-up in food chains, developing methods for environmental bioremediation and for ecological management. There are many gaps in our understanding of the characteristics and mechanisms of plant radionuclide accumulation, including the importance of symbiotically-associated arbuscular mycorrhizal (AM) fungi. We first briefly review the evidence that demonstrates the ability of AM fungi to enhance the translocation of (238)U into plant root tissues, and how fungal association may prevent further mobilization into shoot tissues. We then focus on approaches that should further advance our knowledge of AM fungi-plant radionuclide accumulation. Current research has mostly used artificial cultivation methods and we consider how more ecologically-relevant analysis might be performed. The use of synchrotron-based X-ray fluorescence imaging and absorption spectroscopy techniques to understand the mechanisms of radionuclide transfer from soil to plant via AM fungi is evaluated. Without such further knowledge, the behavior and mobilization of radionuclides cannot be accurately modeled and the potential risks cannot be accurately predicted.

Transfer of fallout radionuclides derived from Fukushima NPP accident: 1 year study on transfer of radionuclides through hydrological processes

NASA Astrophysics Data System (ADS)

Onda, Yuichi; Kato, Hiroaki; Patin, Jeremy; Yoshimura, Kazuya; Tsujimura, Maki; Wakahara, Taeko; Fukushima, Takehiko

2013-04-01

Previous experiences such as Chernobyl Nuclear Power Plant accident have confirmed that fallout radionuclides on the ground surface migrate through natural environment including soils and rivers. Therefore, in order to estimate future changes in radionuclide deposition, migration process of radionuclides in forests, soils, ground water, rivers should be monitored. However, such comprehensive studies on migration through forests, soils, ground water and rivers have not been conducted so far. Here, we present the following comprehensive investigation was conducted to confirm migration of radionuclides through natural environment including soils and rivers. 1)Study on depth distribution of radiocaesium in soils within forests, fields, and grassland 2)Confirmation of radionuclide distribution and investigation on migration in forests 3)Study on radionuclide migration due to soil erosion under different land use 4)Measurement of radionuclides entrained from natural environment including forests and soils 5)Investigation on radionuclide migration through soil water, ground water, stream water, spring water under different land use 6)Study on paddy-to-river transfer of radionuclides through suspended sediments 7)Study on river-to-ocean transfer of radionuclides via suspended sediments 8)Confirmation of radionuclide deposition in ponds and reservoirs

Global Warming.

ERIC Educational Resources Information Center

Hileman, Bette

1989-01-01

States the foundations of the theory of global warming. Describes methodologies used to measure the changes in the atmosphere. Discusses steps currently being taken in the United States and the world to slow the warming trend. Recognizes many sources for the warming and the possible effects on the earth. (MVL)

Wolff-Parkinson-White syndrome type B and left bundle-branch block: electrophysiologic and radionuclide study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rakovec, P.; Kranjec, I.; Fettich, J.J.

1985-01-01

Coinciding left bundle-branch block and Wolff-Parkinson-White syndrome type B, a very rare electrocardiographic occurrence, was found in a patient with dilated cardiomyopathy. Electrophysiologic study revealed eccentric retrograde atrial activation during ventricular pacing, suggesting right-sided accessory pathway. At programmed atrial pacing, effective refractory period of the accessory pathway was 310 ms; at shorter pacing coupling intervals, normal atrioventricular conduction with left bundle-branch block was seen. Left bundle-branch block was seen also with His bundle pacing. Radionuclide phase imaging demonstrated right ventricular phase advance and left ventricular phase delay; both right and left ventricular phase images revealed broad phase distribution histograms. Combinedmore » electrophysiologic and radionuclide investigations are useful to disclose complex conduction abnormalities and their mechanical correlates.« less

Quantification of Local Warming Trend: A Remote Sensing-Based Approach

PubMed Central

Rahaman, Khan Rubayet; Hassan, Quazi K.

2017-01-01

Understanding the warming trends at local level is critical; and, the development of relevant adaptation and mitigation policies at those levels are quite challenging. Here, our overall goal was to generate local warming trend map at 1 km spatial resolution by using: (i) Moderate Resolution Imaging Spectroradiometer (MODIS)-based 8-day composite surface temperature data; (ii) weather station-based yearly average air temperature data; and (iii) air temperature normal (i.e., 30 year average) data over the Canadian province of Alberta during the period 1961–2010. Thus, we analysed the station-based air temperature data in generating relationships between air temperature normal and yearly average air temperature in order to facilitate the selection of year-specific MODIS-based surface temperature data. These MODIS data in conjunction with weather station-based air temperature normal data were then used to model local warming trends. We observed that almost 88% areas of the province experienced warming trends (i.e., up to 1.5°C). The study concluded that remote sensing technology could be useful for delineating generic trends associated with local warming. PMID:28072857

Image-guided interventional therapy for cancer with radiotherapeutic nanoparticles✩

PubMed Central

Phillips, William T.; Bao, Ande; Brenner, Andrew J.; Goins, Beth A.

2015-01-01

One of the major limitations of current cancer therapy is the inability to deliver tumoricidal agents throughout the entire tumor mass using traditional intravenous administration. Nanoparticles carrying beta-emitting therapeutic radionuclides that are delivered using advanced image-guidance have significant potential to improve solid tumor therapy. The use of image-guidance in combination with nanoparticle carriers can improve the delivery of localized radiation to tumors. Nanoparticles labeled with certain beta-emitting radionuclides are intrinsically theranostic agents that can provide information regarding distribution and regional dosimetry within the tumor and the body. Image-guided thermal therapy results in increased uptake of intravenous nanoparticles within tumors, improving therapy. In addition, nanoparticles are ideal carriers for direct intratumoral infusion of beta-emitting radionuclides by convection enhanced delivery, permitting the delivery of localized therapeutic radiation without the requirement of the radionuclide exiting from the nanoparticle. With this approach, very high doses of radiation can be delivered to solid tumors while sparing normal organs. Recent technological developments in image-guidance, convection enhanced delivery and newly developed nanoparticles carrying beta-emitting radionuclides will be reviewed. Examples will be shown describing how this new approach has promise for the treatment of brain, head and neck, and other types of solid tumors. PMID:25016083

Efficient Warm-ups: Creating a Warm-up That Works.

ERIC Educational Resources Information Center

Lauffenburger, Sandra Kay

1992-01-01

Proper warm-up is important for any activity, but designing an effective warm-up can be time consuming. An alternative approach is to take a cue from Laban Movement Analysis (LMA) and consider movement design from the perspective of space and planes of motion. Efficient warm-up exercises using LMA are described. (SM)

Relative roles of differential SST warming, uniform SST warming and land surface warming in determining the Walker circulation changes under global warming

NASA Astrophysics Data System (ADS)

Zhang, Lei; Li, Tim

2017-02-01

Most of CMIP5 models projected a weakened Walker circulation in tropical Pacific, but what causes such change is still an open question. By conducting idealized numerical simulations separating the effects of the spatially uniform sea surface temperature (SST) warming, extra land surface warming and differential SST warming, we demonstrate that the weakening of the Walker circulation is attributed to the western North Pacific (WNP) monsoon and South America land effects. The effect of the uniform SST warming is through so-called "richest-get-richer" mechanism. In response to a uniform surface warming, the WNP monsoon is enhanced by competing moisture with other large-scale convective branches. The strengthened WNP monsoon further induces surface westerlies in the equatorial western-central Pacific, weakening the Walker circulation. The increase of the greenhouse gases leads to a larger land surface warming than ocean surface. As a result, a greater thermal contrast occurs between American Continent and equatorial Pacific. The so-induced zonal pressure gradient anomaly forces low-level westerly anomalies over the equatorial eastern Pacific and weakens the Walker circulation. The differential SST warming also plays a role in driving low-level westerly anomalies over tropical Pacific. But such an effect involves a positive air-sea feedback that amplifies the weakening of both east-west SST gradient and Pacific trade winds.

Daytime warming has stronger negative effects on soil nematodes than night-time warming.

PubMed

Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

2017-03-07

Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

Daytime warming has stronger negative effects on soil nematodes than night-time warming.

PubMed

Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

2017-03-20

Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

Daytime warming has stronger negative effects on soil nematodes than night-time warming

PubMed Central

Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

2017-01-01

Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming. PMID:28317914

Daytime warming has stronger negative effects on soil nematodes than night-time warming

NASA Astrophysics Data System (ADS)

Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

2017-03-01

Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

Radionuclide evaluation of complications after metatarsal osteotomy and implant arthroplasty of the foot

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacobs, A.M.; Klein, S.; Oloff, L.

This paper discusses radionuclide imaging as it applies to bone and implant foot surgery. Where necessary, studies and information from published literature have been extrapolated in an attempt to apply them in differentiating between normal and abnormal healing osteotomies and implant prosthetics.

Simultaneous Tc-99m and I-123 dual-radionuclide imaging with a solid-state detector-based brain-SPECT system and energy-based scatter correction.

PubMed

Takeuchi, Wataru; Suzuki, Atsuro; Shiga, Tohru; Kubo, Naoki; Morimoto, Yuichi; Ueno, Yuichiro; Kobashi, Keiji; Umegaki, Kikuo; Tamaki, Nagara

2016-12-01

A brain single-photon emission computed tomography (SPECT) system using cadmium telluride (CdTe) solid-state detectors was previously developed. This CdTe-SPECT system is suitable for simultaneous dual-radionuclide imaging due to its fine energy resolution (6.6 %). However, the problems of down-scatter and low-energy tail due to the spectral characteristics of a pixelated solid-state detector should be addressed. The objective of this work was to develop a system for simultaneous Tc-99m and I-123 brain studies and evaluate its accuracy. A scatter correction method using five energy windows (FiveEWs) was developed. The windows are Tc-lower, Tc-main, shared sub-window of Tc-upper and I-lower, I-main, and I-upper. This FiveEW method uses pre-measured responses for primary gamma rays from each radionuclide to compensate for the overestimation of scatter by the triple-energy window method that is used. Two phantom experiments and a healthy volunteer experiment were conducted using the CdTe-SPECT system. A cylindrical phantom and a six-compartment phantom with five different mixtures of Tc-99m and I-123 and a cold one were scanned. The quantitative accuracy was evaluated using 18 regions of interest for each phantom. In the volunteer study, five healthy volunteers were injected with Tc-99m human serum albumin diethylene triamine pentaacetic acid (HSA-D) and scanned (single acquisition). They were then injected with I-123 N-isopropyl-4-iodoamphetamine hydrochloride (IMP) and scanned again (dual acquisition). The counts of the Tc-99m images for the single and dual acquisitions were compared. In the cylindrical phantom experiments, the percentage difference (PD) between the single and dual acquisitions was 5.7 ± 4.0 % (mean ± standard deviation). In the six-compartment phantom experiment, the PDs between measured and injected activity for Tc-99m and I-123 were 14.4 ± 11.0 and 2.3 ± 1.8 %, respectively. In the volunteer study, the PD between the single

Accelerated increase in the Arctic tropospheric warming events surpassing stratospheric warming events during winter: Accelerated Increase in Arctic Warming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, S. -Y. Simon; Lin, Yen-Heng; Lee, Ming-Ying

In January 2016, a robust reversal of the Arctic Oscillation (AO) took place associated with a rapid tropospheric warming in the Arctic region; this was followed by the occurrence of a classic sudden stratospheric warming in March-April. The succession of these two distinct Arctic warming events provides a stimulating opportunity to examine their characteristics in terms of similarities and differences. Historical cases of these two types of Arctic warming were identified and validated based upon tropical linkages with the Madden-Julian Oscillation and El Niño as well as those documented in previous studies. Our results indicate a recent and accelerated increasemore » in the tropospheric warming type versus a flat trend in stratospheric warming type. Given that tropospheric warming events occur twice as fast than the stratospheric warming type, the noted increase in the former implies further intensification in midlatitude winter weather extremes similar to those experienced in early 2016. Forced simulations with an atmospheric general circulation model suggest that the reduced Arctic sea ice contributes to the observed increase in the tropospheric warming events and associated impact on the anomalously cold Siberia.« less

Radionuclide evaluation of lung trauma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lull, R.J.; Tatum, J.L.; Sugerman, H.J.

1983-07-01

Nuclear medicine imaging procedures can play a significant role in evaluating the pulmonary complications that are seen in trauma patients. A quantitative method for measuring increased pulmonary capillary permeability that uses Tc-99m HSA allows early diagnosis of acute respiratory distress syndrome (ARDS) and accurately differentiates this condition from pneumonia or cardiogenic pulmonary edema. This technique may be of great value in following the response to therapy. The use of 133Xe to diagnose inhalation injury remains an important diagnostic tool, particularly at hospitals with specialized burn units. Regional decreases in ventilation-perfusion images reliably localize aspirated foreign bodies. Radionuclide techniques that aremore » used to demonstrate gastropulmonary aspiration remain controversial and require further clinical evaluation. Pulmonary perfusion imaging, although nonspecific, may provide the earliest clue for correct diagnosis of fat embolism, air embolism, contusion, or laceration. Furthermore, the possibility of perfusion abnormality due to these uncommon conditions must be remembered whenever trauma patients are evaluated for pulmonary thromboembolism with scintigraphy. Occasionally, liver or spleen scintigraphy may be the most appropriate procedure when penetrating chest trauma also involves these subdiaphragmatic organs.« less

TECHNOLOGIES FOR RADON AND RADIONUCLIDE REMOVAL

EPA Science Inventory

This paper provides a summary of the technologies that are currently being used to remove radionuclides from drinking water. The radionuclides that are featured are the radionuclides currently regulated by EPA; radium, radon and uranium. Tehnologies effective for removal of eac...

Cerenkov luminescence imaging of medical isotopes

PubMed Central

Ruggiero, Alessandro; Holland, Jason P.; Lewis, Jason S.; Grimm, Jan

2011-01-01

The development of novel multimodality imaging agents and techniques represents the current frontier of research in the field of medical imaging science. However, the combination of nuclear tomography with optical techniques has yet to be established. Here, we report the use of the inherent optical emissions from the decay of radiopharmaceuticals for Cerenkov luminescence imaging (CLI) of tumors in vivo and correlate the results with those obtained from concordant immuno-PET studies. Methods In vitro phantom studies were used to validate the visible light emission observed from a range of radionuclides including the positron emitters 18F, 64Cu, 89Zr, and 124I; β-emitter 131I; and α-particle emitter 225Ac for potential use in CLI. The novel radiolabeled monoclonal antibody 89Zr-desferrioxamine B-[DFO-J591 for immuno-PET of prostate-specific membrane antigen (PSMA) expression was used to coregister and correlate the CLI signal observed with the immuno-PET images and biodistribution studies. Results Phantom studies confirmed that Cerenkov radiation can be observed from a range of positron-,β-, and α-emitting radionuclides using standard optical imaging devices. The change in light emission intensity versus time was concordant with radionuclide decay and was also found to correlate linearly with both the activity concentration and the measured PET signal (percentage injected dose per gram). In vivo studies conducted in male severe combined immune deficient mice bearing PSMA-positive, subcutaneous LNCaP tumors demonstrated that tumor-specific uptake of 89Zr-DFO-J591 could be visualized by both immuno-PET and CLI. Optical and immuno-PET signal intensities were found to increase over time from 24 to 96 h, and biodistribution studies were found to correlate well with both imaging modalities. Conclusion These studies represent the first, to our knowledge, quantitative assessment of CLI for measuring radiotracer uptake in vivo. Many radionuclides common to both nuclear

Initial Radionuclide Inventories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, H

The purpose of this analysis is to provide an initial radionuclide inventory (in grams per waste package) and associated uncertainty distributions for use in the Total System Performance Assessment for the License Application (TSPA-LA) in support of the license application for the repository at Yucca Mountain, Nevada. This document is intended for use in postclosure analysis only. Bounding waste stream information and data were collected that capture probable limits. For commercially generated waste, this analysis considers alternative waste stream projections to bound the characteristics of wastes likely to be encountered using arrival scenarios that potentially impact the commercial spent nuclearmore » fuel (CSNF) waste stream. For TSPA-LA, this radionuclide inventory analysis considers U.S. Department of Energy (DOE) high-level radioactive waste (DHLW) glass and two types of spent nuclear fuel (SNF): CSNF and DOE-owned (DSNF). These wastes are placed in two groups of waste packages: the CSNF waste package and the codisposal waste package (CDSP), which are designated to contain DHLW glass and DSNF, or DHLW glass only. The radionuclide inventory for naval SNF is provided separately in the classified ''Naval Nuclear Propulsion Program Technical Support Document'' for the License Application. As noted previously, the radionuclide inventory data presented here is intended only for TSPA-LA postclosure calculations. It is not applicable to preclosure safety calculations. Safe storage, transportation, and ultimate disposal of these wastes require safety analyses to support the design and licensing of repository equipment and facilities. These analyses will require radionuclide inventories to represent the radioactive source term that must be accommodated during handling, storage and disposition of these wastes. This analysis uses the best available information to identify the radionuclide inventory that is expected at the last year of last emplacement, currently

The importance of warm season warming to western U.S. streamflow changes

USGS Publications Warehouse

Das, T.; Pierce, D.W.; Cayan, D.R.; Vano, J.A.; Lettenmaier, D.P.

2011-01-01

Warm season climate warming will be a key driver of annual streamflow changes in four major river basins of the western U.S., as shown by hydrological model simulations using fixed precipitation and idealized seasonal temperature changes based on climate projections with SRES A2 forcing. Warm season (April-September) warming reduces streamflow throughout the year; streamflow declines both immediately and in the subsequent cool season. Cool season (October-March) warming, by contrast, increases streamflow immediately, partially compensating for streamflow reductions during the subsequent warm season. A uniform warm season warming of 3C drives a wide range of annual flow declines across the basins: 13.3%, 7.2%, 1.8%, and 3.6% in the Colorado, Columbia, Northern and Southern Sierra basins, respectively. The same warming applied during the cool season gives annual declines of only 3.5%, 1.7%, 2.1%, and 3.1%, respectively. Copyright 2011 by the American Geophysical Union.

Bifunctional Coupling Agents for Radiolabeling of Biomolecules and Target-Specific Delivery of Metallic Radionuclides

PubMed Central

Liu, Shuang

2008-01-01

Receptor-based radiopharmaceuticals are of great current interest in early molecular imaging and radiotherapy of cancers, and provide a unique tool for target-specific delivery of radionuclides to the diseased tissues. In general, a target-specific radiopharmaceutical can be divided into four parts: targeting biomolecule (BM), pharmacokinetic modifying (PKM) linker, bifunctional coupling or chelating agent (BFC), and radionuclide. The targeting biomolecule serves as a “carrier” for specific delivery of the radionuclide. PKM linkers are used to modify radiotracer excretion kinetics. BFC is needed for radiolabeling of biomolecules with a metallic radionuclide. Different radiometals have significant difference in their coordination chemistry, and require BFCs with different donor atoms and chelator frameworks. Since the radiometal chelate can have a significant impact on physical and biological properties of the target-specific radiopharmaceutical, its excretion kinetics can be altered by modifying the coordination environment with various chelators or coligand, if needed. This review will focus on the design of BFCs and their coordination chemistry with technetium, copper, gallium, indium, yttrium and lanthanide radiometals. PMID:18538888

Design and performance of combined infrared canopy and belowground warming in the B4WarmED (Boreal Forest Warming at an Ecotone in Danger) experiment.

PubMed

Rich, Roy L; Stefanski, Artur; Montgomery, Rebecca A; Hobbie, Sarah E; Kimball, Bruce A; Reich, Peter B

2015-06-01

Conducting manipulative climate change experiments in complex vegetation is challenging, given considerable temporal and spatial heterogeneity. One specific challenge involves warming of both plants and soils to depth. We describe the design and performance of an open-air warming experiment called Boreal Forest Warming at an Ecotone in Danger (B4WarmED) that addresses the potential for projected climate warming to alter tree function, species composition, and ecosystem processes at the boreal-temperate ecotone. The experiment includes two forested sites in northern Minnesota, USA, with plots in both open (recently clear-cut) and closed canopy habitats, where seedlings of 11 tree species were planted into native ground vegetation. Treatments include three target levels of plant canopy and soil warming (ambient, +1.7°C, +3.4°C). Warming was achieved by independent feedback control of voltage input to aboveground infrared heaters and belowground buried resistance heating cables in each of 72-7.0 m(2) plots. The treatments emulated patterns of observed diurnal, seasonal, and annual temperatures but with superimposed warming. For the 2009 to 2011 field seasons, we achieved temperature elevations near our targets with growing season overall mean differences (∆Tbelow ) of +1.84°C and +3.66°C at 10 cm soil depth and (∆T(above) ) of +1.82°C and +3.45°C for the plant canopies. We also achieved measured soil warming to at least 1 m depth. Aboveground treatment stability and control were better during nighttime than daytime and in closed vs. open canopy sites in part due to calmer conditions. Heating efficacy in open canopy areas was reduced with increasing canopy complexity and size. Results of this study suggest the warming approach is scalable: it should work well in small-statured vegetation such as grasslands, desert, agricultural crops, and tree saplings (<5 m tall). © 2015 John Wiley & Sons Ltd.

Positron emission reconstruction tomography for the assessment of regional myocardial metabolism by the administration of substrates labeled with cyclotron produced radionuclides

NASA Technical Reports Server (NTRS)

Ter-Pogossian, M. M.; Hoffman, E. J.; Weiss, E. S.; Coleman, R. E.; Phelps, M. E.; Welch, M. J.; Sobel, B. E.

1975-01-01

A positron emission transverse tomograph device was developed which provides transaxial sectional images of the distribution of positron-emitting radionuclides in the heart. The images provide a quantitative three-dimensional map of the distribution of activity unencumbered by the superimposition of activity originating from regions overlying and underlying the plane of interest. PETT is used primarily with the cyclotron-produced radionuclides oxygen-15, nitrogen-13 and carbon-11. Because of the participation of these atoms in metabolism, they can be used to label metabolic substrates and intermediary molecules incorporated in myocardial metabolism.

Radionuclides: Accumulation and Transport in Plants.

PubMed

Gupta, D K; Chatterjee, S; Datta, S; Voronina, A V; Walther, C

Application of radioactive elements or radionuclides for anthropogenic use is a widespread phenomenon nowadays. Radionuclides undergo radioactive decays releasing ionizing radiation like gamma ray(s) and/or alpha or beta particles that can displace electrons in the living matter (like in DNA) and disturb its function. Radionuclides are highly hazardous pollutants of considerable impact on the environment, food chain and human health. Cleaning up of the contaminated environment through plants is a promising technology where the rhizosphere may play an important role. Plants belonging to the families of Brassicaceae, Papilionaceae, Caryophyllaceae, Poaceae, and Asteraceae are most important in this respect and offer the largest potential for heavy metal phytoremediation. Plants like Lactuca sativa L., Silybum marianum Gaertn., Centaurea cyanus L., Carthamus tinctorius L., Helianthus annuus and H. tuberosus are also important plants for heavy metal phytoremediation. However, transfer factors (TF) of radionuclide from soil/water to plant ([Radionuclide]plant/[Radionuclide]soil) vary widely in different plants. Rhizosphere, rhizobacteria and varied metal transporters like NRAMP, ZIP families CDF, ATPases (HMAs) family like P1B-ATPases, are involved in the radio-phytoremediation processes. This review will discuss recent advancements and potential application of plants for radionuclide removal from the environment.

Method of separating short half-life radionuclides from a mixture of radionuclides

DOEpatents

Bray, Lane A.; Ryan, Jack L.

1999-01-01

The present invention is a method of removing an impurity of plutonium, lead or a combination thereof from a mixture of radionuclides that contains the impurity and at least one parent radionuclide. The method has the steps of (a) insuring that the mixture is a hydrochloric acid mixture; (b) oxidizing the acidic mixture and specifically oxidizing the impurity to its highest oxidation state; and (c) passing the oxidized mixture through a chloride form anion exchange column whereupon the oxidized impurity absorbs to the chloride form anion exchange column and the 22.sup.9 Th or 2.sup.27 Ac "cow" radionuclide passes through the chloride form anion exchange column. The plutonium is removed for the purpose of obtaining other alpha emitting radionuclides in a highly purified form suitable for medical therapy. In addition to plutonium; lead, iron, cobalt, copper, uranium, and other metallic cations that form chloride anionic complexes that may be present in the mixture; are removed from the mixture on the chloride form anion exchange column.

Method of separating short half-life radionuclides from a mixture of radionuclides

DOEpatents

Bray, L.A.; Ryan, J.L.

1999-03-23

The present invention is a method of removing an impurity of plutonium, lead or a combination thereof from a mixture of radionuclides that contains the impurity and at least one parent radionuclide. The method has the steps of (a) insuring that the mixture is a hydrochloric acid mixture; (b) oxidizing the acidic mixture and specifically oxidizing the impurity to its highest oxidation state; and (c) passing the oxidized mixture through a chloride form anion exchange column whereupon the oxidized impurity absorbs to the chloride form anion exchange column and the {sup 229}Th or {sup 227}Ac ``cow`` radionuclide passes through the chloride form anion exchange column. The plutonium is removed for the purpose of obtaining other alpha emitting radionuclides in a highly purified form suitable for medical therapy. In addition to plutonium, lead, iron, cobalt, copper, uranium, and other metallic cations that form chloride anionic complexes that may be present in the mixture are removed from the mixture on the chloride form anion exchange column. 8 figs.

EANM guidelines for radionuclide therapy of bone metastases with beta-emitting radionuclides.

PubMed

Handkiewicz-Junak, Daria; Poeppel, Thorsten D; Bodei, Lisa; Aktolun, Cumali; Ezziddin, Samer; Giammarile, Francesco; Delgado-Bolton, Roberto C; Gabriel, Michael

2018-05-01

The skeleton is the most common metastatic site in patients with advanced cancer. Pain is a major healthcare problem in patients with bone metastases. Bone-seeking radionuclides that selectively accumulate in the bone are used to treat cancer-induced bone pain and to prolong survival in selected groups of cancer patients. The goals of these guidelines are to assist nuclear medicine practitioners in: (a) evaluating patients who might be candidates for radionuclide treatment of bone metastases using beta-emitting radionuclides such as strontium-89 ( 89 Sr), samarium-153 ( 153 Sm) lexidronam ( 153 Sm-EDTMP), and phosphorus-32 ( 32 P) sodium phosphate; (b) performing the treatments; and ©) understanding and evaluating the treatment outcome and side effects.

Identification of CSF fistulas by radionuclide counting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamamoto, Y.; Kunishio, K.; Sunami, N.

1990-07-01

A radionuclide counting method, performed with the patient prone and the neck flexed, was used successfully to diagnose CSF rhinorrhea in two patients. A normal radionuclide ratio (radionuclide counts in pledget/radionuclide counts in 1-ml blood sample) was obtained in 11 normal control subjects. Significance was determined to be a ratio greater than 0.37. Use of radionuclide counting method of determining CSF rhinorrhea is recommended when other methods have failed to locate a site of leakage or when posttraumatic meningitis suggests subclinical CSF rhinorrhea.

What Sets the Radial Locations of Warm Debris Disks?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ballering, Nicholas P.; Rieke, George H.; Su, Kate Y. L.

The architectures of debris disks encode the history of planet formation in these systems. Studies of debris disks via their spectral energy distributions (SEDs) have found infrared excesses arising from cold dust, warm dust, or a combination of the two. The cold outer belts of many systems have been imaged, facilitating their study in great detail. Far less is known about the warm components, including the origin of the dust. The regularity of the disk temperatures indicates an underlying structure that may be linked to the water snow line. If the dust is generated from collisions in an exo-asteroid belt,more » the dust will likely trace the location of the water snow line in the primordial protoplanetary disk where planetesimal growth was enhanced. If instead the warm dust arises from the inward transport from a reservoir of icy material farther out in the system, the dust location is expected to be set by the current snow line. We analyze the SEDs of a large sample of debris disks with warm components. We find that warm components in single-component systems (those without detectable cold components) follow the primordial snow line rather than the current snow line, so they likely arise from exo-asteroid belts. While the locations of many warm components in two-component systems are also consistent with the primordial snow line, there is more diversity among these systems, suggesting additional effects play a role.« less

How the public engages with global warming: A social representations approach.

PubMed

Smith, Nicholas; Joffe, Helene

2013-01-01

The present study utilises social representations theory to explore common sense conceptualisations of global warming risk using an in-depth, qualitative methodology. Fifty-six members of a British, London-based 2008 public were initially asked to draw or write four spontaneous "first thoughts or feelings" about global warming. These were then explored via an open-ended, exploratory interview. The analysis revealed that first thoughts, either drawn or written, often mirrored the images used by the British press to depict global warming visually. Thus in terms of media framings, it was their visual rather than their textual content that was spontaneously available for their audiences. Furthermore, an in-depth exploration of interview data revealed that global warming was structured around three themata: self/other, natural/unnatural and certainty/uncertainty, reflecting the complex and often contradictory nature of common sense thinking in relation to risk issues.

Radionuclide Retention in Concrete Wasteforms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wellman, Dawn M.; Jansik, Danielle P.; Golovich, Elizabeth C.

2012-09-24

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate predictionmore » of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of LLW and MLLW, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.« less

Nanoparticle imaging probes for molecular imaging with computed tomography and application to cancer imaging

NASA Astrophysics Data System (ADS)

Roeder, Ryan K.; Curtis, Tyler E.; Nallathamby, Prakash D.; Irimata, Lisa E.; McGinnity, Tracie L.; Cole, Lisa E.; Vargo-Gogola, Tracy; Cowden Dahl, Karen D.

2017-03-01

Precision imaging is needed to realize precision medicine in cancer detection and treatment. Molecular imaging offers the ability to target and identify tumors, associated abnormalities, and specific cell populations with overexpressed receptors. Nuclear imaging and radionuclide probes provide high sensitivity but subject the patient to a high radiation dose and provide limited spatiotemporal information, requiring combined computed tomography (CT) for anatomic imaging. Therefore, nanoparticle contrast agents have been designed to enable molecular imaging and improve detection in CT alone. Core-shell nanoparticles provide a powerful platform for designing tailored imaging probes. The composition of the core is chosen for enabling strong X-ray contrast, multi-agent imaging with photon-counting spectral CT, and multimodal imaging. A silica shell is used for protective, biocompatible encapsulation of the core composition, volume-loading fluorophores or radionuclides for multimodal imaging, and facile surface functionalization with antibodies or small molecules for targeted delivery. Multi-agent (k-edge) imaging and quantitative molecular imaging with spectral CT was demonstrated using current clinical agents (iodine and BaSO4) and a proposed spectral library of contrast agents (Gd2O3, HfO2, and Au). Bisphosphonate-functionalized Au nanoparticles were demonstrated to enhance sensitivity and specificity for the detection of breast microcalcifications by conventional radiography and CT in both normal and dense mammary tissue using murine models. Moreover, photon-counting spectral CT enabled quantitative material decomposition of the Au and calcium signals. Immunoconjugated Au@SiO2 nanoparticles enabled highly-specific targeting of CD133+ ovarian cancer stem cells for contrast-enhanced detection in model tumors.

Modeling Radionuclide Decay Chain Migration Using HYDROGEOCHEM

NASA Astrophysics Data System (ADS)

Lin, T. C.; Tsai, C. H.; Lai, K. H.; Chen, J. S.

2014-12-01

Nuclear technology has been employed for energy production for several decades. Although people receive many benefits from nuclear energy, there are inevitably environmental pollutions as well as human health threats posed by the radioactive materials releases from nuclear waste disposed in geological repositories or accidental releases of radionuclides from nuclear facilities. Theoretical studies have been undertaken to understand the transport of radionuclides in subsurface environments because that the radionuclide transport in groundwater is one of the main pathway in exposure scenarios for the intake of radionuclides. The radionuclide transport in groundwater can be predicted using analytical solution as well as numerical models. In this study, we simulate the transport of the radionuclide decay chain using HYDROGEOCHEM. The simulated results are verified against the analytical solution available in the literature. Excellent agreements between the numerical simulation and the analytical are observed for a wide spectrum of concentration. HYDROGECHEM is a useful tool assessing the ecological and environmental impact of the accidental radionuclide releases such as the Fukushima nuclear disaster where multiple radionuclides leaked through the reactor, subsequently contaminating the local groundwater and ocean seawater in the vicinity of the nuclear plant.

Measurement of radionuclides in waste packages

DOEpatents

Brodzinski, R.L.; Perkins, R.W.; Rieck, H.G.; Wogman, N.A.

1984-09-12

A method is described for non-destructively assaying the radionuclide content of solid waste in a sealed container by analysis of the waste's gamma-ray spectrum and neutron emissions. Some radionuclides are measured by characteristic photopeaks in the gamma-ray spectrum; transuranic nuclides are measured by neutron emission rate; other radionuclides are measured by correlation with those already measured.

Measurement of radionuclides in waste packages

DOEpatents

Brodzinski, Ronald L.; Perkins, Richard W.; Rieck, Henry G.; Wogman, Ned A.

1986-01-01

A method is described for non-destructively assaying the radionuclide content of solid waste in a sealed container by analysis of the waste's gamma-ray spectrum and neutron emissions. Some radionuclides are measured by characteristic photopeaks in the gamma-ray spectrum; transuranic nuclides are measured by neutron emission rate; other radionuclides are measured by correlation with those already measured.

Clinically Approved Nanoparticle Imaging Agents

PubMed Central

Thakor, Avnesh S.; Jokerst, Jesse V.; Ghanouni, Pejman; Campbell, Jos L.; Mittra, Erik

2016-01-01

Nanoparticles are a new class of imaging agent used for both anatomic and molecular imaging. Nanoparticle-based imaging exploits the signal intensity, stability, and biodistribution behavior of submicron-diameter molecular imaging agents. This review focuses on nanoparticles used in human medical imaging, with an emphasis on radionuclide imaging and MRI. Newer nanoparticle platforms are also discussed in relation to theranostic and multimodal uses. PMID:27738007

Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy

NASA Astrophysics Data System (ADS)

Bednarz, Bryan; Besemer, Abigail

2017-09-01

The use of radionuclide therapy in the clinical setting is expected to increase significantly over the next decade. There is an important need to understand the radiation-induced second cancer risk associated with these procedures. In this study the radiation-induced cancer risk in five radionuclide therapy patients was investigated. These patients underwent serial SPECT imaging scans following injection as part of a clinical trial testing the efficacy of a 131Iodine-labeled radiopharmaceutical. Using these datasets the committed absorbed doses to multiple sensitive structures were calculated using RAPID, which is a novel Monte Carlo-based 3D dosimetry platform developed for personalized dosimetry. The excess relative risk (ERR) for radiation-induced cancer in these structures was then derived from these dose estimates following the recommendations set forth in the BEIR VII report. The radiation-induced leukemia ERR was highest among all sites considered reaching a maximum value of approximately 4.5. The radiation-induced cancer risk in the kidneys, liver and spleen ranged between 0.3 and 1.3. The lifetime attributable risks (LARs) were also calculated, which ranged from 30 to 1700 cancers per 100,000 persons and were highest for leukemia and the liver for both males and females followed by radiation-induced spleen and kidney cancer. The risks associated with radionuclide therapy are similar to the risk associated with external beam radiation therapy.

Longitudinal Changes in Tear Evaporation Rates After Eyelid Warming Therapies in Meibomian Gland Dysfunction.

PubMed

Yeo, Sharon; Tan, Jen Hong; Acharya, U Rajendra; Sudarshan, Vidya K; Tong, Louis

2016-04-01

Lid warming is the major treatment for meibomian gland dysfunction (MGD). The purpose of the study was to determine the longitudinal changes of tear evaporation after lid warming in patients with MGD. Ninety patients with MGD were enrolled from a dry eye clinic at Singapore National Eye Center in an interventional trial. Participants were treated with hot towel (n = 22), EyeGiene (n = 22), or Blephasteam (n = 22) twice daily or a single 12-minute session of Lipiflow (n = 24). Ocular surface infrared thermography was performed at baseline and 4 and 12 weeks after the treatment, and image features were extracted from the captured images. The baseline of conjunctival tear evaporation (TE) rate (n = 90) was 66.1 ± 21.1 W/min. The rates were not significantly different between sexes, ages, symptom severities, tear breakup times, Schirmer test, corneal fluorescein staining, or treatment groups. Using a general linear model (repeat measures), the conjunctival TE rate was reduced with time after treatment. A higher baseline evaporation rate (≥ 66 W/min) was associated with greater reduction of evaporation rate after treatment. Seven of 10 thermography features at baseline were predictive of reduction in irritative symptoms after treatment. Conjunctival TE rates can be effectively reduced by lid warming treatment in some MGD patients. Individual baseline thermography image features can be predictive of the response to lid warming therapy. For patients that do not have excessive TE, additional therapy, for example, anti-inflammatory therapy, may be required.

Local warming: daily temperature change influences belief in global warming.

PubMed

Li, Ye; Johnson, Eric J; Zaval, Lisa

2011-04-01

Although people are quite aware of global warming, their beliefs about it may be malleable; specifically, their beliefs may be constructed in response to questions about global warming. Beliefs may reflect irrelevant but salient information, such as the current day's temperature. This replacement of a more complex, less easily accessed judgment with a simple, more accessible one is known as attribute substitution. In three studies, we asked residents of the United States and Australia to report their opinions about global warming and whether the temperature on the day of the study was warmer or cooler than usual. Respondents who thought that day was warmer than usual believed more in and had greater concern about global warming than did respondents who thought that day was colder than usual. They also donated more money to a global-warming charity if they thought that day seemed warmer than usual. We used instrumental variable regression to rule out some alternative explanations.

Targeted Nuclear Imaging Probes for Cardiac Amyloidosis.

PubMed

Bravo, Paco E; Dorbala, Sharmila

2017-07-01

The aim of the present manuscript is to review the latest advancements of radionuclide molecular imaging in the diagnosis and prognosis of individuals with cardiac amyloidosis. 99m Technetium labeled bone tracer scintigraphy had been known to image cardiac amyloidosis, since the 1980s; over the past decade, bone scintigraphy has been revived specifically to diagnose transthyretin cardiac amyloidosis. 18 F labeled and 11 C labeled amyloid binding radiotracers developed for imaging Alzheimer's disease, have been repurposed since 2013, to image light chain and transthyretin cardiac amyloidosis. 99m Technetium bone scintigraphy for transthyretin cardiac amyloidosis, and amyloid binding targeted PET imaging for light chain and transthyretin cardiac amyloidosis, are emerging as highly accurate methods. Targeted radionuclide imaging may soon replace endomyocardial biopsy in the evaluation of patients with suspected cardiac amyloidosis. Further research is warranted on the role of targeted imaging to quantify cardiac amyloidosis and to guide therapy.

The effects of warmed intravenous fluids, combined warming (warmed intravenous fluids with humid-warm oxygen), and pethidine on the severity of shivering in general anesthesia patients in the recovery room

PubMed Central

Nasiri, Ahmad; Akbari, Ayob; Sharifzade, GholamReza; Derakhshan, Pooya

2015-01-01

Background: Shivering is a common complication of general and epidural anesthesia. Warming methods and many drugs are used for control of shivering in the recovery room. The present study is a randomized clinical trial aimed to investigate the effects of two interventions in comparison with pethidine which is the routine treatment on shivering in patients undergoing abdominal surgery with general anesthesia. Materials and Methods: Eighty-seven patients undergoing abdominal surgery by general anesthesia were randomly assigned to three groups (two intervention groups in comparison with pethidine as routine). Patients in warmed intravenous fluids group received pre-warmed Ringer serum (38°C), patients in combined warming group received pre-warmed Ringer serum (38°C) accompanied by humid-warm oxygen, and patients in pethidine group received intravenous pethidine routinely. The elapsed time of shivering and some hemodynamic parameters of the participants were assessed for 20 min postoperatively in the recovery room. Then the collected data were analyzed by software SPSS (v. 16) with the significance level being P < 0.05. Results: The mean of elapsed time in the warmed intravenous serum group, the combined warming group, and the pethidine group were 7 (1.5) min, 6 (1.5) min, and 2.8 (0.7) min, respectively, which was statistically significant (P < 0.05). The body temperatures in both combined warming and pethidine groups were increased significantly (P < 0.05). Conclusions: Combined warming can be effective in controlling postoperative shivering and body temperature increase. PMID:26793258

Direct intratumoral infusion of liposome encapsulated rhenium radionuclides for cancer therapy: Effects of nonuniform intratumoral dose distribution

PubMed Central

Hrycushko, Brian A.; Li, Shihong; Goins, Beth; Otto, Randal A.; Bao, Ande

2011-01-01

Purpose: Focused radiation therapy by direct intratumoral infusion of lipid nanoparticle (liposome)-carried beta-emitting radionuclides has shown promising results in animal model studies; however, little is known about the impact the intratumoral liposomal radionuclide distribution may have on tumor control. The primary objective of this work was to investigate the effects the intratumoral absorbed dose distributions from this cancer therapy modality have on tumor control and treatment planning by combining dosimetric and radiobiological modeling with in vivo imaging data. Methods:99mTc-encapsulated liposomes were intratumorally infused with a single injection location to human head and neck squamous cell carcinoma xenografts in nude rats. High resolution in vivo planar imaging was performed at various time points for quantifying intratumoral retention following infusion. The intratumoral liposomal radioactivity distribution was obtained from 1 mm resolution pinhole collimator SPECT imaging coregistered with CT imaging of excised tumors at 20 h postinfusion. Coregistered images were used for intratumoral dosimetric and radiobiological modeling at a voxel level following extrapolation to the therapeutic analogs, 186Re∕188Re liposomes. Effective uniform dose (EUD) and tumor control probability (TCP) were used to assess therapy effectiveness and possible methods of improving upon tumor control with this radiation therapy modality. Results: Dosimetric analysis showed that average tumor absorbed doses of 8.6 Gy∕MBq (318.2 Gy∕mCi) and 5.7 Gy∕MBq (209.1 Gy∕mCi) could be delivered with this protocol of radiation delivery for 186Re∕188Re liposomes, respectively, and 37–92 MBq (1–2.5 mCi)∕g tumor administered activity; however, large intratumoral absorbed dose heterogeneity, as seen in dose-volume histograms, resulted in insignificant values of EUD and TCP for achieving tumor control. It is indicated that the use of liposomes encapsulating radionuclides

Direct intratumoral infusion of liposome encapsulated rhenium radionuclides for cancer therapy: Effects of nonuniform intratumoral dose distribution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hrycushko, Brian A.; Li Shihong; Goins, Beth

2011-03-15

Purpose: Focused radiation therapy by direct intratumoral infusion of lipid nanoparticle (liposome)-carried beta-emitting radionuclides has shown promising results in animal model studies; however, little is known about the impact the intratumoral liposomal radionuclide distribution may have on tumor control. The primary objective of this work was to investigate the effects the intratumoral absorbed dose distributions from this cancer therapy modality have on tumor control and treatment planning by combining dosimetric and radiobiological modeling with in vivo imaging data. Methods: {sup 99m}Tc-encapsulated liposomes were intratumorally infused with a single injection location to human head and neck squamous cell carcinoma xenografts inmore » nude rats. High resolution in vivo planar imaging was performed at various time points for quantifying intratumoral retention following infusion. The intratumoral liposomal radioactivity distribution was obtained from 1 mm resolution pinhole collimator SPECT imaging coregistered with CT imaging of excised tumors at 20 h postinfusion. Coregistered images were used for intratumoral dosimetric and radiobiological modeling at a voxel level following extrapolation to the therapeutic analogs, {sup 186}Re/{sup 188}Re liposomes. Effective uniform dose (EUD) and tumor control probability (TCP) were used to assess therapy effectiveness and possible methods of improving upon tumor control with this radiation therapy modality. Results: Dosimetric analysis showed that average tumor absorbed doses of 8.6 Gy/MBq (318.2 Gy/mCi) and 5.7 Gy/MBq (209.1 Gy/mCi) could be delivered with this protocol of radiation delivery for {sup 186}Re/{sup 188}Re liposomes, respectively, and 37-92 MBq (1-2.5 mCi)/g tumor administered activity; however, large intratumoral absorbed dose heterogeneity, as seen in dose-volume histograms, resulted in insignificant values of EUD and TCP for achieving tumor control. It is indicated that the use of liposomes

A whole-body dual-modality radionuclide optical strategy for preclinical imaging of metastasis and heterogeneous treatment response in different microenvironments.

PubMed

Fruhwirth, Gilbert O; Diocou, Seckou; Blower, Philip J; Ng, Tony; Mullen, Greg E D

2014-04-01

Imaging spontaneous cancer cell metastasis or heterogeneous tumor responses to drug treatment in vivo is difficult to achieve. The goal was to develop a new highly sensitive and reliable preclinical longitudinal in vivo imaging model for this purpose, thereby facilitating discovery and validation of anticancer therapies or molecular imaging agents. The strategy is based on breast cancer cells stably expressing the human sodium iodide symporter (NIS) fused to a red fluorescent protein, thereby permitting radionuclide and fluorescence imaging. Using whole-body nano-SPECT/CT with (99m)TcO4(-), we followed primary tumor growth and spontaneous metastasis in the presence or absence of etoposide treatment. NIS imaging was used to classify organs as small as individual lymph nodes (LNs) to be positive or negative for metastasis, and results were confirmed by confocal fluorescence microscopy. Etoposide treatment efficacy was proven by ex vivo anticaspase 3 staining and fluorescence microscopy. In this preclinical model, we found that the NIS imaging strategy outperformed state-of-the-art (18)F-FDG imaging in its ability to detect small tumors (18.5-fold-better tumor-to-blood ratio) and metastases (LN, 3.6-fold) because of improved contrast in organs close to metastatic sites (12- and 8.5-fold-lower standardized uptake value in the heart and kidney, respectively). We applied the model to assess the treatment response to the neoadjuvant etoposide and found a consistent and reliable improvement in spontaneous metastasis detection. Importantly, we also found that tumor cells in different microenvironments responded in a heterogeneous manner to etoposide treatment, which could be determined only by the NIS-based strategy and not by (18)F-FDG imaging. We developed a new strategy for preclinical longitudinal in vivo cancer cell tracking with greater sensitivity and reliability than (18)F-FDG PET and applied it to track spontaneous and distant metastasis in the presence or absence

Evaluation of dead-time corrections for post-radionuclide-therapy (177)Lu quantitative imaging with low-energy high-resolution collimators.

PubMed

Celler, Anna; Piwowarska-Bilska, Hanna; Shcherbinin, Sergey; Uribe, Carlos; Mikolajczak, Renata; Birkenfeld, Bozena

2014-01-01

Dead-time (DT) effects rarely cause problems in diagnostic single-photon emission computed tomography (SPECT) studies; however, in post-radionuclide-therapy imaging, DT can be substantial. Therefore, corrections may be necessary if quantitative images are used in image-based dosimetry or for evaluation of therapy outcomes. This task is particularly challenging if low-energy collimators are used. Our goal was to design a simple method to determine the dead-time correction factor (DTCF) without the need for phantom experiments and complex calculations. Planar and SPECT/CT scans of a water phantom containing a 70 ml bottle filled with lutetium-177 (Lu) were acquired over 60 days. Two small Lu markers were used in all scans. The DTCF based on the ratio of observed to true count rates measured over the entire spectrum and using photopeak primary photons only was estimated for phantom (DT present) and marker (no DT) scans. In addition, variations in counts in SPECT projections (potentially caused by varying bremsstrahlung and scatter) were investigated. For count rates that were about two-fold higher than typically seen in post-therapy Lu scans, the maximum DTCF reached a level of about 17%. The DTCF values determined directly from the phantom experiments using the total energy spectrum and photopeak counts only were equal to 13 and 16%, respectively. They were closely matched by those from the proposed marker-based method, which uses only two energy windows and measures photopeak primary photons (15-17%). A simple, marker-based method allowing for determination of the DTCF in high-activity Lu imaging studies has been proposed and validated using phantom experiments.

Gamma-Ray Focusing Optics for Small Animal Imaging

NASA Technical Reports Server (NTRS)

Pivovaroff, M. J.; Barber, W. C.; Craig, W. W.; Hasegawa, B. H.; Ramsey, B. D.; Taylor, C.

2004-01-01

There is a well-established need for high-resolution radionuclide imaging techniques that provide non-invasive measurement of physiological function in small animals. We, therefore, have begun developing a small animal radionuclide imaging system using grazing incidence mirrors to focus low-energy gamma-rays emitted by I-125, and other radionuclides. Our initial prototype optic, fabricated from thermally-formed glass, demonstrated a resolution of 1500 microns, consistent with the performance predicted by detailed simulations. More recently, we have begun constructing mirrors using a replication technique that reduces low spatial frequency errors in the mirror surface, greatly improving the resolution. Each technique offers particular advantages: e.g., multilayer coatings are easily deposited on glass, while superior resolution is possible with replicated optics. Scaling the results from our prototype optics, which only have a few nested shells, to system where the lens has a full complement of several tens of nested shells, a sensitivity of approx. 1 cps/micro Ci is possible, with the exact number dependent on system magnification and radionuclide species. (Higher levels of efficiency can be obtained with multi-optic imaging systems.) The gamma-ray lens will achieve a resolution as good as 100 microns, independent of the final sensitivity. The combination of high spatial resolution and modest sensitivity will enable in vivo single photon emission imaging studies in small animals.

Warm-adapted microbial communities enhance their carbon-use efficiency in warmed soils

NASA Astrophysics Data System (ADS)

Rousk, Johannes; Frey, Serita

2017-04-01

Ecosystem models predict that climate warming will stimulate microbial decomposition of soil carbon (C), resulting in a positive feedback to increasing temperatures. The current generation of models assume that the temperature sensitivities of microbial processes do not respond to warming. However, recent studies have suggested that the ability of microbial communities to adapt to warming can lead both strengthened and weakened feedbacks. A further complication is that the balance between microbial C used for growth to that used for respiration - the microbial carbon-use efficiency (CUE) - also has been shown through both modelling and empirical study to respond to warming. In our study, we set out to assess how chronic warming (+5°C over ambient during 9 years) of a temperate hardwood forest floor (Harvard Forest LTER, USA) affected temperature sensitivities of microbial processes in soil. To do this, we first determined the temperature relationships for bacterial growth, fungal growth, and respiration in plots exposed to warmed or ambient conditions. Secondly, we parametrised the established temperature functions microbial growth and respiration with plot-specific measured soil temperature data at a hourly time-resolution over the course of 3 years to estimate the real-time variation of in situ microbial C production and respiration. To estimate the microbial CUE, we also divided the microbial C production with the sum of microbial C production and respiration as a proxy for substrate use. We found that warm-adapted bacterial and fungal communities both shifted their temperature relationships to grow at higher rates in warm conditions which coincided with reduced rates at cool conditions. As such, their optimal temperature (Topt), minimum temperature (Tmin) and temperature sensitivity (Q10) were all increased. The temperature relationship for temperature, in contrast, was only marginally shifted in the same direction, but at a much smaller effect size, with

Radionuclide labeled lymphocytes for therapeutic use

DOEpatents

Srivastava, Suresh C.; Fawwaz, Rashid A.; Richards, Powell

1985-01-01

Lymphocytes labelled with .beta.-emitting radionuclides are therapeutically useful, particularly for lymphoid ablation. They are prepared by incubation of the lymphocytes with the selected radionuclide-oxine complex.

Radionuclide labeled lymphocytes for therapeutic use

DOEpatents

Srivastava, S.C.; Fawwaz, R.A.; Richards, P.

1983-05-03

Lymphocytes labelled with ..beta..-emitting radionuclides are therapeutically useful, particularly for lymphoid ablation. They are prepared by incubation of the lymphocytes with the selected radionuclide-oxine complex.

Radionuclide Retention in Concrete Wasteforms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bovaird, Chase C.; Jansik, Danielle P.; Wellman, Dawn M.

2011-09-30

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate predictionmore » of radionuclide fate when the wasteforms come in contact with groundwater. The information present in the report provides data that (1) measures the effect of concrete wasteform properties likely to influence radionuclide migration; and (2) quantifies the rate of carbonation of concrete materials in a simulated vadose zone repository.« less

Warm-up Practices in Elite Boxing Athletes: Impact on Power Output.

PubMed

Cunniffe, Brian; Ellison, Mark; Loosemore, Mike; Cardinale, Marco

2017-01-01

Cunniffe, B, Ellison, M, Loosemore, M, and Cardinale, M. Warm-up practices in elite boxing athletes: Iimpact on power output. J Strength Cond Res 31(1): 95-105, 2017-This study evaluated the performance impact of routine warm-up strategies in elite Olympic amateur boxing athletes and physiological implications of the time gap (GAP) between warm-up and boxing activity. Six male boxers were assessed while performing standardized prefight warm-up routines. Core and skin temperature measurements (Tcore and Tskin), heart rate, and upper- and lower-body power output (PO) were assessed before and after warm-up, during a 25-minutes GAP and after 3 × 2 minutes rounds of sparring. Reflected temperature (Tc) was also determined using high-resolution thermal images at fixed time-points to explore avenues for heat loss. Despite individual differences in warm-up duration (range 7.4-18.5 minutes), increases in Tcore and Tskin occurred (p ≤ 0.05). Corresponding increases (4.8%; p ≤ 0.05) in countermovement jump (CMJ) height and upward-rightward shifts in upper-body force-velocity and power-velocity curves were observed. Athletes remained inactive during the 25-minutes GAP with a gradual and significant increase in Tc occurring by the end of GAP suggesting the likelihood of heat loss. Decreases in CMJ height and upper-body PO were observed after 15 minutes and 25 minutes GAP (p ≤ 0.05). By the end of GAP period, all performance variables had returned to pre-warm-up values. Results suggest routine warm-ups undertaken by elite boxers have acute effects on power-generating capacity. Gradual decreases in performance variables are evident with inactivity and seem related to alterations in body temperature. Considering the constraints of major competitions and time spent in air conditioned holding areas before fights, practitioners should be aware of the potential of nullifying the warm-up effects.

Accelerated increase in the Arctic tropospheric warming events surpassing stratospheric warming events during winter

NASA Astrophysics Data System (ADS)

Wang, S.-Y. Simon; Lin, Yen-Heng; Lee, Ming-Ying; Yoon, Jin-Ho; Meyer, Jonathan D. D.; Rasch, Philip J.

2017-04-01

In January 2016, a robust reversal of the Arctic Oscillation took place associated with a rapid tropospheric warming in the Arctic region; this was followed by the occurrence of a classic sudden stratospheric warming in March. The succession of these two distinct Arctic warming events provides a stimulating opportunity to examine their characteristics in terms of similarities and differences. Historical cases of these two types of Arctic warming were identified and validated based upon tropical linkages with the Madden-Julian Oscillation and El Niño as documented in previous studies. The analysis indicates a recent and seemingly accelerated increase in the tropospheric warming type versus a flat trend in stratospheric warming type. The shorter duration and more rapid transition of tropospheric warming events may connect to the documented increase in midlatitude weather extremes, more so than the route of stratospheric warming type. Forced simulations with an atmospheric general circulation model suggest that the reduced Arctic sea ice contributes to the observed increase in the tropospheric warming events and associated remarkable strengthening of the cold Siberian high manifest in 2016.

Radionuclide concentration processes in marine organisms: A comprehensive review.

PubMed

Carvalho, Fernando P

2018-06-01

The first measurements made of artificial radionuclides released into the marine environment did reveal that radionuclides are concentrated by marine biological species. The need to report radionuclide accumulation in biota in different conditions and geographical areas prompted the use of concentration factors as a convenient way to describe the accumulation of radionuclides in biota relative to radionuclide concentrations in seawater. Later, concentration factors became a tool in modelling radionuclide distribution and transfer in aquatic environments and to predicting radioactivity in organisms. Many environmental parameters can modify the biokinetics of accumulation and elimination of radionuclides in marine biota, but concentration factors remained a convenient way to describe concentration processes of radioactive and stable isotopes in aquatic organisms. Revision of CF values is periodically undertaken by international organizations, such as the International Atomic Energy Agency (IAEA), to make updated information available to the international community. A brief commented review of radionuclide concentration processes and concentration factors in marine organisms is presented for key groups of radionuclides such as fission products, activation products, transuranium elements, and naturally-occurring radionuclides. Copyright © 2017 Elsevier Ltd. All rights reserved.

Colloid labelled with radionuclide and method

DOEpatents

Atcher, Robert W.; Hines, John J.

1990-01-01

A ferric hydroxide colloid having an alpha-emitting radionuclide essentially on the outer surfaces and a method of forming same. The method includes oxidizing a ferrous hydroxide to ferric hydroxide in the presence of a preselected radionuclide to form a colloid having the radionuclide on the outer surface thereof, and thereafter washing the colloid, and suspending the washed colloid in a suitable solution. The labelled colloid is useful in cancer therapy and for the treatment of inflamed joints.

Warm up I: potential mechanisms and the effects of passive warm up on exercise performance.

PubMed

Bishop, David

2003-01-01

Despite limited scientific evidence supporting their effectiveness, warm-up routines prior to exercise are a well-accepted practice. The majority of the effects of warm up have been attributed to temperature-related mechanisms (e.g. decreased stiffness, increased nerve-conduction rate, altered force-velocity relationship, increased anaerobic energy provision and increased thermoregulatory strain), although non-temperature-related mechanisms have also been proposed (e.g. effects of acidaemia, elevation of baseline oxygen consumption (.VO(2)) and increased postactivation potentiation). It has also been hypothesised that warm up may have a number of psychological effects (e.g. increased preparedness). Warm-up techniques can be broadly classified into two major categories: passive warm up or active warm up. Passive warm up involves raising muscle or core temperature by some external means, while active warm up utilises exercise. Passive heating allows one to obtain the increase in muscle or core temperature achieved by active warm up without depleting energy substrates. Passive warm up, although not practical for most athletes, also allows one to test the hypothesis that many of the performance changes associated with active warm up can be largely attributed to temperature-related mechanisms.

Detecting low levels of radionuclides in fluids

DOEpatents

Patch, Keith D.; Morgan, Dean T.

2000-01-01

An apparatus and method for detecting low levels of one or more radionuclides in a fluid sample uses a substrate that includes an ion exchange resin or other sorbent material to collect the radionuclides. A collecting apparatus includes a collecting chamber that exposes the substrate to a measured amount of the fluid sample such that radionuclides in the fluid sample are collected by the ion exchange resin. A drying apparatus, which can include a drying chamber, then dries the substrate. A measuring apparatus measures emissions from radionuclides collected on the substrate. The substrate is positioned in a measuring chamber proximate to a detector, which provides a signal in response to emissions from the radionuclides. Other analysis methods can be used to detect non-radioactive analytes, which can be collected with other types of sorbent materials.

Copper Loading of Preformed Nanoparticles for PET-Imaging Applications.

PubMed

Lu, Hoang D; Wang, Leon Z; Wilson, Brian K; McManus, Simon A; Jumai'an, Jenny; Padakanti, Prashanth K; Alavi, Abass; Mach, Robert H; Prud'homme, Robert K

2018-01-31

Nanoparticles (NP) are promising contrast agents for positron emission tomography (PET) radionuclide imaging that can increase signal intensity by localizing clusters of PET radionuclides together. However, methods to load NPs with PET radionuclides suffer from harsh loading conditions or poor loading efficacies or result in NP surface modifications that alter targeting in vivo. We present the formation of water-dispersible, polyethylene glycol coated NPs that encapsulate phthalocyanines into NP cores at greater than 50 wt % loading, using the self-assembly technique Flash NanoPrecipitation. Particles from 70 to 160 nm are produced. Phthalocyanine NPs rapidly and spontaneously chelate metals under mild conditions and can act as sinks for PET radionuclides such as 64-Cu to produce PET-active NPs. NPs chelate copper(II) with characteristic rates of 1845 M -1 h -1 at pH 6 and 37 °C, which produced >90% radionuclide chelation within 1 h. NP physical properties, such as core composition, core fluidity, and size, can be tuned to modulate chelation kinetics. These NPs retain 64 Cu even in the presence of the strong chelator ethylene diamine tetraacetic acid. The development of these constructs for rapid and facile radionuclide labeling expands the applications of NP-based PET imaging.

Radionuclides in Chesapeake Bay sediments

NASA Technical Reports Server (NTRS)

Cressy, P. J., Jr.

1976-01-01

Natural and manmade gamma-ray emitting radionuclides were measured in Chesapeake Bay sediments taken near the Calvert Cliffs Nuclear Power Plant site. Samples represented several water depths, at six locations, for five dates encompassing a complete seasonal cycle. Radionuclide contents of dry sediments ranged as follows: Tl-208, 40 to 400 pCi/kg; Bi-214, 200 to 800 pCi/kg; K, 0.04 to 2.1 percent; Cs-137 5 to 1900 pCi/kg; Ru106, 40 to 1000 pCikg Co60, 1 to 27 pCi/kg. In general, radionuclide contents were positively correlated with each other and negatively correlated with sediment grain size.

Warming shifts 'worming': effects of experimental warming on invasive earthworms in northern North America.

PubMed

Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A; Rice, Karen; Rich, Roy; Reich, Peter B

2014-11-03

Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration.

Accelerated Increase in the Arctic Tropospheric Warming Events Surpassing StratosphericWarming Events During Winter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Simon; Lin, Yen-Heng; Lee, Ming-Ying

2017-04-22

In January 2016, a robust reversal of the Arctic Oscillation (AO) took place associated with a rapid tropospheric warming in the Arctic region; this was followed by the occurrence of a classic sudden stratospheric warming in March-April. The succession of these two distinct Arctic warming events provides a stimulating opportunity to examine their characteristics in terms of similarities and differences. Historical cases of these two types of Arctic warming were identified and validated based upon tropical linkages with the Madden-Julian Oscillation and El Niño as well as those documented in previous studies. Our results indicate a recent and accelerated increasemore » in the tropospheric warming type versus a flat trend in stratospheric warming type. Given that tropospheric warming events occur twice as fast than the stratospheric warming type, the noted increase in the former implies further intensification in midlatitude winter weather extremes similar to those experienced in early 2016. Forced simulations with an atmospheric general circulation model suggest that the reduced Arctic sea ice contributes to the observed increase in the tropospheric warming events and associated impact on the anomalously cold Siberia.« less

Radionuclide injury to the lung.

PubMed Central

Dagle, G E; Sanders, C L

1984-01-01

Radionuclide injury to the lung has been studied in rats, hamsters, dogs, mice and baboons. Exposure of the lung to high dose levels of radionuclides produces a spectrum of progressively more severe functional and morphological changes, ranging from radiation pneumonitis and fibrosis to lung tumors. These changes are somewhat similar for different species. Their severity can be related to the absorbed radiation dose (measured in rads) produced by alpha, beta or gamma radiation emanating from various deposited radionuclides. The chemicophysical forms of radionuclides and spatial-temporal factors are also important variables. As with other forms of injury to the lung, repair attempts are highlighted by fibrosis and proliferation of pulmonary epithelium. Lung tumors are the principal late effect observed in experimental animals following pulmonary deposition of radionuclides at dose levels that do not result in early deaths from radiation pneumonitis or fibrosis. The predominant lung tumors described have been of epithelial origin and have been classified, in decreasing frequency of occurrence, as adenocarcinoma, bronchioloalveolar carcinoma, epidermoid carcinomas and combined epidermoid and adenocarcinoma. Mesothelioma and fibrosarcoma have been observed in rats, but less commonly in other species. Hemangiosarcomas were frequency observed in dogs exposed to beta-gamma emitters, and occasionally in rats exposed to alpha emitters. These morphologic changes in the lungs of experimental animals were reviewed and issues relevant to the prediction of human hazards discussed. PMID:6376095

Colloid labelled with radionuclide and method

DOEpatents

Atcher, R.W.; Hines, J.J.

1990-11-13

A ferric hydroxide colloid having an alpha-emitting radionuclide essentially on the outer surfaces and a method of forming same. The method includes oxidizing a ferrous hydroxide to ferric hydroxide in the presence of a preselected radionuclide to form a colloid having the radionuclide on the outer surface thereof, and thereafter washing the colloid, and suspending the washed colloid in a suitable solution. The labelled colloid is useful in cancer therapy and for the treatment of inflamed joints. No Drawings

Tissue warming and regulatory responses induced by radio frequency energy deposition on a whole-body 3-Tesla magnetic resonance imager.

PubMed

Boss, Andreas; Graf, Hansjörg; Berger, Alexander; Lauer, Ulrike A; Wojtczyk, Hanne; Claussen, Claus D; Schick, Fritz

2007-11-01

To quantify the B1-field induced tissue warming on a 3T-whole-body scanner, to test whether the patient is able to sense the temperature change, and to evaluate whether the imaging procedure constitutes a significant cardiovascular stress. A total of 18 volunteers were divided into three equal groups for 3.0T MRI of the pelvis, the head, or the knee. An imaging protocol operating at first level mode was applied, allowing radio frequency (RF) irradiation up to the legal specific absorption rate (SAR) limits. An identical placebo protocol with active gradient switching but without RF transmission was used. Temperature changes were measured with a fiber-optic thermometer (FO) and an infrared camera (IR). Temperature differences to the placebo were highest for imaging of the pelvis (FO: DeltaT = 0.88 +/- 0.13 degrees C, IR: DeltaT = 1.01 +/- 0.15 degrees C) as compared to the head (FO: DeltaT = 0.46 +/- 0.12 degrees C, IR: DeltaT = 0.47 +/- 0.10 degrees C) and the knee (FO: DeltaT = 0.33 +/- 0.11 degrees C, IR: DeltaT = 0.37 +/- 0.09 degrees C). The volunteers were able to discriminate between imaging and placebo for pelvic (P < 0.0001) and head (P = 0.0005) imaging but not for knee imaging (P = 0.209). No changes in heart rate or blood pressure were detected. The 3.0T MRI in the first operational mode may lead to measurable and perceptible thermal energy deposition. However, it may be regarded as safe concerning the thermoregulatory cardiovascular stress.

Radionuclide cisternogram

MedlinePlus

... please enable JavaScript. A radionuclide cisternogram is a nuclear scan test. It is used to diagnose problems ... damage. The amount of radiation used during the nuclear scan is very small. Almost all of the ...

Radionuclide studies in Hodgkin's disease and lymphomas.

PubMed

Richman, S D; Levenson, S M; Jones, A E; Johnston, G S

1975-01-01

A rational, multidisciplinary approach to Hodgkin's disease and the non-Hodgkin's lymphomas has been responsible for major advances in therapy. Invasive diagnostic procedures and exploratory laparotomy, with their associated complications, make nontraumatic radionuclide imaging most appealing in both the clinical staging of disease and in evaluating therapy. Gallium-67-citrate, the tumor scanning agent of the early 1970's, has demonstrated a marked affinity for Hodgkin's disease and the other lymphomas. False positives are few, with sensitivity greater than 70% throughout the spectrum of Hodgkin's disease and the histiocytic lymphomas. In addition to confirming sites of suspected neoplasm, this agent has proved useful in the detection of occult involvement. Moreover, resolution of abnormal gallium-67 concentrations on follow-up studies functions as a visual ancillary index of therapeutic response. The value of wholebody gallium-67 scintigraphy is further enhanced when used in conjunction with routine technetium brain, bone, liver, and spleen scans. While the diagnostic accuracy of gallium-67 studies has been limited in the abdomen due to bowel activity, our attempts to improve these results with the tumor-seeking radiopharmaceutical indium-111-Bleomycin were unrewarding and subsequently were discontinued. Finally, radionuclide lymphography has also been explored. Its diagnostic usefulness in detecting pelvic and abdominal lymph node involvement warrants further investigation.

Modeling radionuclide migration from underground nuclear explosions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harp, Dylan Robert; Stauffer, Philip H.; Viswanathan, Hari S.

2017-03-06

The travel time of radionuclide gases to the ground surface in fracture rock depends on many complex factors. Numerical simulators are the most complete repositories of knowledge of the complex processes governing radionuclide gas migration to the ground surface allowing us to verify conceptualizations of physical processes against observations and forecast radionuclide gas travel times to the ground surface and isotopic ratios

Selected radionuclides important to low-level radioactive waste management

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-11-01

The purpose of this document is to provide information to state representatives and developers of low level radioactive waste (LLW) management facilities about the radiological, chemical, and physical characteristics of selected radionuclides and their behavior in the environment. Extensive surveys of available literature provided information for this report. Certain radionuclides may contribute significantly to the dose estimated during a radiological performance assessment analysis of an LLW disposal facility. Among these are the radionuclides listed in Title 10 of the Code of Federal Regulations Part 61.55, Tables 1 and 2 (including alpha emitting transuranics with half-lives greater than 5 years). Thismore » report discusses these radionuclides and other radionuclides that may be significant during a radiological performance assessment analysis of an LLW disposal facility. This report not only includes essential information on each radionuclide, but also incorporates waste and disposal information on the radionuclide, and behavior of the radionuclide in the environment and in the human body. Radionuclides addressed in this document include technetium-99, carbon-14, iodine-129, tritium, cesium-137, strontium-90, nickel-59, plutonium-241, nickel-63, niobium-94, cobalt-60, curium -42, americium-241, uranium-238, and neptunium-237.« less

Conditions and processes affecting radionuclide transport

USGS Publications Warehouse

Simmons, Ardyth M.; Neymark, Leonid A.

2012-01-01

Understanding of unsaturated-zone transport is based on laboratory and field-scale experiments. Fractures provide advective transport pathways. Sorption and matrix diffusion may contribute to retardation of radionuclides. Conversely, sorption onto mobile colloids may enhance radionuclide transport.

Global Warming: A Reduced Threat?.

NASA Astrophysics Data System (ADS)

Michaels, Patrick J.; Stooksbury, David E.

1992-10-01

One popular and apocalyptic vision of the world influenced by increasing concentrations of infrared-absorbing trace gases is that of ecological disaster brought about by rapidly rising temperatures, sea level, and evaporation rates. This vision developed from a suite of climate models that have since considerably changed in both their dynamics and their estimates of prospective warming. Observed temperatures indicate that much more warming should already have taken place than predicted by earlier models in the Northern Hemisphere, and that night, rather than day, readings in that hemisphere show a relative warming. A high-latitude polar-night warming or a general night warming could be either benign or beneficial. A large number of plant species show both increased growth and greater water-use efficiency under enhanced carbon dioxide.An extensive body of evidence now indicates that anthropo-generated sulfate emissions are mitigating some of the warming, and that increased cloudiness as a result of these emissions will further enhance night, rather than day, warming. The sulfate emissions, though, are not sufficient to explain all of the night warming. However, the sensitivity of climate to anthropogenerated aerosols, and the general lack of previously predicted warming, could drastically alter the debate on global warming in favor of less expensive policies.

TOPEX/El Nino Watch - El Nino Warm Water Pool Decreasing, Jan, 08, 1998

NASA Technical Reports Server (NTRS)

1998-01-01

This image of the Pacific Ocean was produced using sea surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Jan. 8, 1998, and sea surface height is an indicator of the heat content of the ocean. The volume of the warm water pool related to the El Nino has decreased by about 40 percent since its maximum in early November, but the area of the warm water pool is still about one and a half times the size of the continental United States. The volume measurements are computed as the sum of all the sea surface height changes as compared to normal ocean conditions. In addition, the maximum water temperature in the eastern tropical Pacific, as measured by the National Oceanic and Atmospheric Administration (NOAA), is still higher than normal. Until these high temperatures diminish, the El Nino warm water pool still has great potential to disrupt global weather because the high water temperatures directly influence the atmosphere. Oceanographers believe the recent decrease in the size of the warm water pool is a normal part of El Nino's natural rhythm. TOPEX/Poseidon has been tracking these fluctuations of the El Nino warm pool since it began in early 1997. These sea surface height measurements have provided scientists with their first detailed view of how El Nino's warm pool behaves because the TOPEX/Poseidon satellite measures the changing sea surface height with unprecedented precision. In this image, the white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal; in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level.

The El Nino phenomenon is thought to be triggered when the steady westward blowing trade winds

Implementation and applications of dual-modality imaging

NASA Astrophysics Data System (ADS)

Hasegawa, Bruce H.; Barber, William C.; Funk, Tobias; Hwang, Andrew B.; Taylor, Carmen; Sun, Mingshan; Seo, Youngho

2004-06-01

In medical diagnosis, functional or physiological data can be acquired using radionuclide imaging with positron emission tomography or with single-photon emission computed tomography. However, anatomical or structural data can be acquired using X-ray computed tomography. In dual-modality imaging, both radionuclide and X-ray detectors are incorporated in an imaging system to allow both functional and structural data to be acquired in a single procedure without removing the patient from the imaging system. In a clinical setting, dual-modality imaging systems commonly are used to localize radiopharmaceutical uptake with respect to the patient's anatomy. This helps the clinician to differentiate disease from regions of normal radiopharmaceutical accumulation, to improve diagnosis or cancer staging, or to facilitate planning for radiation therapy or surgery. While initial applications of dual-modality imaging were developed for clinical imaging on humans, it now is recognized that these systems have potentially important applications for imaging small animals involved in experimental studies including basic investigations of mammalian biology and development of new pharmaceuticals for diagnosis or treatment of disease.

Was Early Mars Warmed by CH4?

NASA Astrophysics Data System (ADS)

Justh, H. L.; Kasting, J. F.

2001-12-01

Images from the Mariner, Viking and Mars Global Surveyor missions have shown geologic features on the Martian surface that seem to indicate an earlier period of hydrologic activity. Many researchers have suggested that the early Martian climate was more Earth-like with a Ts of 273 K or higher. The presence of liquid water would require a greenhouse effect much larger than needed at present since S0 is 25% lower 3.8 billion years ago when the channels are thought to have formed. Research into the effects of CO2 clouds upon the climate of early Mars have yielded results that would not effectively warm the surface to the temperature needed to account for the presence of liquid water. Forget and Pierrehumbert (Science, 1997) showed that large crystals of CO2 ice in clouds that form in the upper troposphere would produce a strong warming effect. Obtaining mean surface temperatures above 273 K would require 100% cloud cover, a condition that is unrealistic for early Mars. It has also been shown that any reduction in cloud cover makes it difficult to achieve warm Martian surface temperatures except at high pressures. CO2 clouds could also cool the Martian surface if they were low and optically thick. CO2 ice may be hard to nucleate, leading to the formation of very large particles (Glandorf, private communication). CH4 has been suggested as an important greenhouse gas on the early Earth. This has led us to look at CH4 as a potential solution to the early Mars climate issue. To investigate the possible warming effect of CH4, we utilized a modified, one-dimensional, radiative-convective climate model that has been used in previous studies of the early Martian climate. New calculations of the effects of CH4 upon the early Martian climate will be presented. The use of CH4 to warm the surface of early Mars does not necessarily imply the presence of life on Mars. Abiotic sources of CH4, such as serpentinization of ultramafic rocks, could supply the concentrations needed to warm

Chlorotoxin-Conjugated Multifunctional Dendrimers Labeled with Radionuclide 131I for Single Photon Emission Computed Tomography Imaging and Radiotherapy of Gliomas.

PubMed

Zhao, Lingzhou; Zhu, Jingyi; Cheng, Yongjun; Xiong, Zhijuan; Tang, Yueqin; Guo, Lilei; Shi, Xiangyang; Zhao, Jinhua

2015-09-09

Chlorotoxin-conjugated multifunctional dendrimers labeled with radionuclide 131I were synthesized and utilized for targeted single photon emission computed tomography (SPECT) imaging and radiotherapy of cancer. In this study, generation five amine-terminated poly(amidoamine) dendrimers were used as a platform to be sequentially conjugated with polyethylene glycol (PEG), targeting agent chlorotoxin (CTX), and 3-(4'-hydroxyphenyl)propionic acid-OSu (HPAO). This was followed by acetylation of the remaining dendrimer terminal amines and radiolabeling with 131I to form the targeted theranostic dendrimeric nanoplatform. We show that the dendrimer platform possessing approximately 7.7 CTX and 21.1 HPAO moieties on each dendrimer displays excellent cytocompatibility in a given concentration range (0-20 μM) and can specifically target cancer cells overexpressing matrix metallopeptidase 2 (MMP2) due to the attached CTX. With the attached HPAO moiety having the phenol group, the dendrimer platform can be effectively labeled with radioactive 131I with good stability and high radiochemical purity. Importantly, the 131I labeling renders the dendrimer platform with an ability to be used for targeted SPECT imaging and radiotherapy of an MMP2-overexpressing glioma model in vivo. The developed radiolabeled multifunctional dendrimeric nanoplatform may hold great promise to be used for targeted theranostics of human gliomas.

Why Popper can't resolve the debate over global warming: Problems with the uses of philosophy of science in the media and public framing of the science of global warming.

PubMed

Mercer, David

2018-02-01

A notable feature in the public framing of debates involving the science of Anthropogenic Global Warming are appeals to uncritical 'positivist' images of the ideal scientific method. Versions of Sir Karl Popper's philosophy of falsification appear most frequently, featuring in many Web sites and broader media. This use of pop philosophy of science forms part of strategies used by critics, mainly from conservative political backgrounds, to manufacture doubt, by setting unrealistic standards for sound science, in the veracity of science of Anthropogenic Global Warming. It will be shown, nevertheless, that prominent supporters of Anthropogenic Global Warming science also often use similar references to Popper to support their claims. It will also be suggested that this pattern reflects longer traditions of the use of Popperian philosophy of science in controversial settings, particularly in the United States, where appeals to the authority of science to legitimize policy have been most common. It will be concluded that studies of the science of Anthropogenic Global Warming debate would benefit from taking greater interest in questions raised by un-reflexive and politically expedient public understanding(s) of the philosophy of science of both critics and supporters of the science of Anthropogenic Global Warming.

Warming shifts ‘worming': effects of experimental warming on invasive earthworms in northern North America

PubMed Central

Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A.; Rice, Karen; Rich, Roy; Reich, Peter B.

2014-01-01

Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration. PMID:25363633

The Role of Emotion in Global Warming Policy Support and Opposition

PubMed Central

Smith, Nicholas; Leiserowitz, Anthony

2014-01-01

Prior research has found that affect and affective imagery strongly influence public support for global warming. This article extends this literature by exploring the separate influence of discrete emotions. Utilizing a nationally representative survey in the United States, this study found that discrete emotions were stronger predictors of global warming policy support than cultural worldviews, negative affect, image associations, or sociodemographic variables. In particular, worry, interest, and hope were strongly associated with increased policy support. The results contribute to experiential theories of risk information processing and suggest that discrete emotions play a significant role in public support for climate change policy. Implications for climate change communication are also discussed. PMID:24219420

Active Movement Warm-Up Routines

ERIC Educational Resources Information Center

Walter, Teri; Quint, Ashleigh; Fischer, Kim; Kiger, Joy

2011-01-01

This article presents warm-ups that are designed to physiologically and psychologically prepare students for vigorous physical activity. An active movement warm-up routine is made up of three parts: (1) active warm-up movement exercises, (2) general preparation, and (3) the energy system. These warm-up routines can be used with all grade levels…

Seasonal flows on warm Martian slopes

USGS Publications Warehouse

McEwen, A.S.; Ojha, L.; Dundas, C.M.; Mattson, S.S.; Byrne, S.; Wray, J.J.; Cull, S.C.; Murchie, S.L.; Thomas, N.; Gulick, V.C.

2011-01-01

Water probably flowed across ancient Mars, but whether it ever exists as a liquid on the surface today remains debatable. Recurring slope lineae (RSL) are narrow (0.5 to 5 meters), relatively dark markings on steep (25?? to 40??) slopes; repeat images from the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment show them to appear and incrementally grow during warm seasons and fade in cold seasons. They extend downslope from bedrock outcrops, often associated with small channels, and hundreds of them form in some rare locations. RSL appear and lengthen in the late southern spring and summer from 48??S to 32??S latitudes favoring equator-facing slopes, which are times and places with peak surface temperatures from ???250 to 300 kelvin. Liquid brines near the surface might explain this activity, but the exact mechanism and source of water are not understood.

Therapeutic radionuclides in nuclear medicine: current and future prospects

PubMed Central

Yeong, Chai-Hong; Cheng, Mu-hua; Ng, Kwan-Hoong

2014-01-01

The potential use of radionuclides in therapy has been recognized for many decades. A number of radionuclides, such as iodine-131 (131I), phosphorous-32 (32P), strontium-90 (90Sr), and yttrium-90 (90Y), have been used successfully for the treatment of many benign and malignant disorders. Recently, the rapid growth of this branch of nuclear medicine has been stimulated by the introduction of a number of new radionuclides and radiopharmaceuticals for the treatment of metastatic bone pain and neuroendocrine and other malignant or non-malignant tumours. Today, the field of radionuclide therapy is enjoying an exciting phase and is poised for greater growth and development in the coming years. For example, in Asia, the high prevalence of thyroid and liver diseases has prompted many novel developments and clinical trials using targeted radionuclide therapy. This paper reviews the characteristics and clinical applications of the commonly available therapeutic radionuclides, as well as the problems and issues involved in translating novel radionuclides into clinical therapies. PMID:25294374

The dynamic monitoring of warm-water discharge based on the airborne high-resolution thermal infrared remote sensing data

NASA Astrophysics Data System (ADS)

Shao, Honglan; Xie, Feng; Liu, Chengyu; Liu, Zhihui; Zhang, Changxing; Yang, Gui; Wang, Jianyu

2016-04-01

The cooling water discharged from the coastal plants flow into the sea continuously, whose temperature is higher than original sea surface temperature (SST). The fact will have non-negligible influence on the marine environment in and around where the plants site. Hence, it's significant to monitor the temporal and spatial variation of the warm-water discharge for the assessment of the effect of the plant on its surrounding marine environment. The paper describes an approach for the dynamic monitoring of the warm-water discharge of coastal plants based on the airborne high-resolution thermal infrared remote sensing technology. Firstly, the geometric correction was carried out for the thermal infrared remote sensing images acquired on the aircraft. Secondly, the atmospheric correction method was used to retrieve the sea surface temperature of the images. Thirdly, the temperature-rising districts caused by the warm-water discharge were extracted. Lastly, the temporal and spatial variations of the warm-water discharge were analyzed through the geographic information system (GIS) technology. The approach was applied to Qinshan nuclear power plant (NPP), in Zhejiang Province, China. In considering with the tide states, the diffusion, distribution and temperature-rising values of the warm-water discharged from the plant were calculated and analyzed, which are useful to the marine environment assessment.

Warm Mix Asphalt

DOT National Transportation Integrated Search

2009-04-17

State of Alaska State of Alaska - Warm Mix Project Warm Mix Project: Location - Petersburg, Alaska which is Petersburg, Alaska which is located in the heart of Southeast Alaska located in the heart of Southeast Alaska's Inside Passage at the tip of M...

Analysis of fission and activation radionuclides produced by a uranium-fueled nuclear detonation and identification of the top dose-producing radionuclides.

PubMed

Kraus, Terry; Foster, Kevin

2014-08-01

The radiological assessment of the nuclear fallout (i.e., fission and neutron-activation radionuclides) from a nuclear detonation is complicated by the large number of fallout radionuclides. This paper provides the initial isotopic source term inventory of the fallout from a uranium-fueled nuclear detonation and identifies the significant and insignificant radiological dose producing radionuclides over 11 dose integration time periods (time phases) of interest. A primary goal of this work is to produce a set of consistent, time phase-dependent lists of the top dose-producing radionuclides that can be used to prepare radiological assessment calculations and data products (e.g., maps of areas that exceed protective action guidelines) in support of public and worker protection decisions. The ranked lists of top dose-producing radionuclides enable assessors to perform atmospheric dispersion modeling and radiological dose assessment modeling more quickly by using relatively short lists of radionuclides without significantly compromising the accuracy of the modeling and the dose projections. This paper also provides a superset-list of the top dose-producing fallout radionuclides from a uranium-fueled nuclear detonation that can be used to perform radiological assessments over any desired time phase. Furthermore, this paper provides information that may be useful to monitoring and sampling and laboratory analysis personnel to help understand which radionuclides are of primary concern. Finally, this paper may be useful to public protection decision makers because it shows the importance of quickly initiating public protection actions to minimize the radiological dose from fallout.

Case-study magnetic resonance imaging and acoustic investigation of the effects of vocal warm-up on two voice professionals.

PubMed

Laukkanen, Anne-Maria; Horáček, Jaromir; Havlík, Radan

2012-07-01

Vocal warm-up (WU)-related changes were studied in one male musical singer and one female speech trainer. They sustained vowels before and after WU in a magnetic resonance imaging (MRI) device. Acoustic recordings were made in a studio. The vocal tract area increased after WU, a formant cluster appeared between 2 and 4.5 kHz, and SPL increased. Evidence of larynx lowering was only found for the male. The pharyngeal inlet over the epilaryngeal outlet ratio (A(ph)/A(e)) increased by 10%-28%, being 3-4 for the male and 5-7 for the female. The results seem to represent different voice training traditions. A singer's formant cluster may be achievable without a high A(ph)/A(e) (≥ 6), but limitations of the 2D method should be taken into account.

Method of making colloid labeled with radionuclide

DOEpatents

Atcher, Robert W.; Hines, John J.

1991-01-01

A ferric hydroxide colloid having an alpha-emitting radionuclide essentially on the outer surfaces and a method of forming same. The method includes oxidizing a ferrous hydroxide to ferric hydroxide in the presence of a preselected radionuclide to form a colloid having the radionuclide on the outer surface thereof, and thereafter washing the colloid, and suspending the washed colloid in a suitable solution. The labelled colloid is useful in cancer therapy and for the treatment of inflamed joints.

How warm days increase belief in global warming

NASA Astrophysics Data System (ADS)

Zaval, Lisa; Keenan, Elizabeth A.; Johnson, Eric J.; Weber, Elke U.

2014-02-01

Climate change judgements can depend on whether today seems warmer or colder than usual, termed the local warming effect. Although previous research has demonstrated that this effect occurs, studies have yet to explain why or how temperature abnormalities influence global warming attitudes. A better understanding of the underlying psychology of this effect can help explain the public's reaction to climate change and inform approaches used to communicate the phenomenon. Across five studies, we find evidence of attribute substitution, whereby individuals use less relevant but available information (for example, today's temperature) in place of more diagnostic but less accessible information (for example, global climate change patterns) when making judgements. Moreover, we rule out alternative hypotheses involving climate change labelling and lay mental models. Ultimately, we show that present temperature abnormalities are given undue weight and lead to an overestimation of the frequency of similar past events, thereby increasing belief in and concern for global warming.

Fast analysis of radionuclide decay chain migration

NASA Astrophysics Data System (ADS)

Chen, J. S.; Liang, C. P.; Liu, C. W.; Li, L.

2014-12-01

A novel tool for rapidly predicting the long-term plume behavior of an arbitrary length radionuclide decay chain is presented in this study. This fast tool is achieved based on generalized analytical solutions in compact format derived for a set of two-dimensional advection-dispersion equations coupled with sequential first-order decay reactions in groundwater system. The performance of the developed tool is evaluated by a numerical model using a Laplace transform finite difference scheme. The results of performance evaluation indicate that the developed model is robust and accurate. The developed model is then used to fast understand the transport behavior of a four-member radionuclide decay chain. Results show that the plume extents and concentration levels of any target radionuclide are very sensitive to longitudinal, transverse dispersion, decay rate constant and retardation factor. The developed model are useful tools for rapidly assessing the ecological and environmental impact of the accidental radionuclide releases such as the Fukushima nuclear disaster where multiple radionuclides leaked through the reactor, subsequently contaminating the local groundwater and ocean seawater in the vicinity of the nuclear plant.

Evaluation of NASA GEOS-ADAS Modeled Diurnal Warming Through Comparisons to SEVIRI and AMSR2 SST Observations

NASA Astrophysics Data System (ADS)

Gentemann, C. L.; Akella, S.

2018-02-01

An analysis of the ocean skin Sea Surface Temperature (SST) has been included in the Goddard Earth Observing System (GEOS) - Atmospheric Data Assimilation System (ADAS), Version 5 (GEOS-ADAS). This analysis is based on the GEOS atmospheric general circulation model (AGCM) that simulates near-surface diurnal warming and cool skin effects. Analysis for the skin SST is performed along with the atmospheric state, including Advanced Very High Resolution Radiometer (AVHRR) satellite radiance observations as part of the data assimilation system. One month (September, 2015) of GEOS-ADAS SSTs were compared to collocated satellite Spinning Enhanced Visible and InfraRed Imager (SEVIRI) and Advanced Microwave Scanning Radiometer 2 (AMSR2) SSTs to examine how the GEOS-ADAS diurnal warming compares to the satellite measured warming. The spatial distribution of warming compares well to the satellite observed distributions. Specific diurnal events are analyzed to examine variability within a single day. The dependence of diurnal warming on wind speed, time of day, and daily average insolation is also examined. Overall the magnitude of GEOS-ADAS warming is similar to the warming inferred from satellite retrievals, but several weaknesses in the GEOS-AGCM simulated diurnal warming are identified and directly related back to specific features in the formulation of the diurnal warming model.

Dual-modality imaging of function and physiology

NASA Astrophysics Data System (ADS)

Hasegawa, Bruce H.; Iwata, Koji; Wong, Kenneth H.; Wu, Max C.; Da Silva, Angela; Tang, Hamilton R.; Barber, William C.; Hwang, Andrew B.; Sakdinawat, Anne E.

2002-04-01

Dual-modality imaging is a technique where computed tomography or magnetic resonance imaging is combined with positron emission tomography or single-photon computed tomography to acquire structural and functional images with an integrated system. The data are acquired during a single procedure with the patient on a table viewed by both detectors to facilitate correlation between the structural and function images. The resulting data can be useful for localization for more specific diagnosis of disease. In addition, the anatomical information can be used to compensate the correlated radionuclide data for physical perturbations such as photon attenuation, scatter radiation, and partial volume errors. Thus, dual-modality imaging provides a priori information that can be used to improve both the visual quality and the quantitative accuracy of the radionuclide images. Dual-modality imaging systems also are being developed for biological research that involves small animals. The small-animal dual-modality systems offer advantages for measurements that currently are performed invasively using autoradiography and tissue sampling. By acquiring the required data noninvasively, dual-modality imaging has the potential to allow serial studies in a single animal, to perform measurements with fewer animals, and to improve the statistical quality of the data.

Intrinsically radiolabelled [(59)Fe]-SPIONs for dual MRI/radionuclide detection.

PubMed

Hoffman, David; Sun, Minghao; Yang, Likun; McDonagh, Philip R; Corwin, Frank; Sundaresan, Gobalakrishnan; Wang, Li; Vijayaragavan, Vimalan; Thadigiri, Celina; Lamichhane, Narottam; Zweit, Jamal

2014-01-01

Towards the development of iron oxide nanoparticles with intrinsically incorporated radionuclides for dual Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) and more recently of Single Photon Emission Computed Tomography/Magnetic Resonance Imaging (SPECT/MRI), we have developed intrinsically radiolabeled [(59)Fe]-superparamagnetic iron oxide nanoparticles ([(59)Fe]-SPIONs) as a proof of concept for an intrinsic dual probe strategy. (59)Fe was incorporated into Fe3O4 nanoparticle crystal lattice with 92±3% efficiency in thermal decomposition synthesis. Multidentate poly(acrylic acid)-dopamine-poly(ethylene-glycol-2000) (PAA-DOP-PEG) ligands were designed and synthesized based on facile EDC chemistry and utilized to functionalize the [(59)Fe]-SPIONs. The transverse relaxivity of [(59)Fe]-SPIONs (97±3 s(-1)mM(-1)) was characterized and found to be similar to non-radioactive SPIONs (72±10 s(-1)mM(-1)), indicating that (59)Fe incorporation does not alter the SPIONs' MRI contrast properties. [(59)Fe]-SPIONs were used to evaluate the nanoparticle biodistribution by ex vivo gamma counting and MRI. Nude mice (n=15) were injected with [(59)Fe]-SPIONs and imaged at various time points with 7T small animal MRI scanner. Ex vivo biodistribution was evaluated by tissue-based gamma counting. MRI signal contrast qualitatively correlates with the %ID/g of [(59)Fe]-SPIONs, with high contrast in liver (45±6%), medium contrast in kidneys (21±5%), and low contrast in brain (4±6%) at 24 hours. This work demonstrates the synthesis and in vivo application of intrinsically radiolabeled [(59)Fe]-SPIONs for bimodal detection and provides a proof of concept for incorporation of both gamma- and positron-emitting inorganic radionuclides into the core of metal based MRI contrast agent nanoparticles.

The role of emotion in global warming policy support and opposition.

PubMed

Smith, Nicholas; Leiserowitz, Anthony

2014-05-01

Prior research has found that affect and affective imagery strongly influence public support for global warming. This article extends this literature by exploring the separate influence of discrete emotions. Utilizing a nationally representative survey in the United States, this study found that discrete emotions were stronger predictors of global warming policy support than cultural worldviews, negative affect, image associations, or sociodemographic variables. In particular, worry, interest, and hope were strongly associated with increased policy support. The results contribute to experiential theories of risk information processing and suggest that discrete emotions play a significant role in public support for climate change policy. Implications for climate change communication are also discussed. © 2013 Society for Risk Analysis.

VizieR Online Data Catalog: Spitzer obs. of warm dust in 83 debris disks (Ballering+, 2017)

NASA Astrophysics Data System (ADS)

Ballering, N. P.; Rieke, G. H.; Su, K. Y. L.; Gaspar, A.

2018-04-01

For our sample, we used the systems with a warm component found by Ballering+ (2013, J/ApJ/775/55), where "warm" was defined as warmer than 130K. All of these systems have data available from the Multiband Imaging Photometer for Spitzer (MIPS) at 24 and 70um and from the Spitzer Infrared Spectrograph (IRS). The selected 83 targets used for our analysis are listed in Table 1. (5 data files).

Seasonal flows on warm Martian slopes

USGS Publications Warehouse

McEwen, Alfred S.; Ojha, Lujendra; Dundas, Colin M.; Mattson, Sarah S.; Byrne, Shane; Wray, James J.; Cull, Selby C.; Murchie, Scott L.; Thomas, Nicolas; Gulick, Virginia C.

2011-01-01

Water probably flowed across ancient Mars, but whether it ever exists as a liquid on the surface today remains debatable. Recurring slope lineae (RSL) are narrow (0.5 to 5 meters), relatively dark markings on steep (25° to 40°) slopes; repeat images from the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment show them to appear and incrementally grow during warm seasons and fade in cold seasons. They extend downslope from bedrock outcrops, often associated with small channels, and hundreds of them form in some rare locations. RSL appear and lengthen in the late southern spring and summer from 48°S to 32°S latitudes favoring equator-facing slopes, which are times and places with peak surface temperatures from ~250 to 300 kelvin. Liquid brines near the surface might explain this activity, but the exact mechanism and source of water are not understood.

Seasonal flows on warm Martian slopes.

PubMed

McEwen, Alfred S; Ojha, Lujendra; Dundas, Colin M; Mattson, Sarah S; Byrne, Shane; Wray, James J; Cull, Selby C; Murchie, Scott L; Thomas, Nicolas; Gulick, Virginia C

2011-08-05

Water probably flowed across ancient Mars, but whether it ever exists as a liquid on the surface today remains debatable. Recurring slope lineae (RSL) are narrow (0.5 to 5 meters), relatively dark markings on steep (25° to 40°) slopes; repeat images from the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment show them to appear and incrementally grow during warm seasons and fade in cold seasons. They extend downslope from bedrock outcrops, often associated with small channels, and hundreds of them form in some rare locations. RSL appear and lengthen in the late southern spring and summer from 48°S to 32°S latitudes favoring equator-facing slopes, which are times and places with peak surface temperatures from ~250 to 300 kelvin. Liquid brines near the surface might explain this activity, but the exact mechanism and source of water are not understood.

Adsorption of radionuclides on the monolayer MoS2

NASA Astrophysics Data System (ADS)

Zhao, Qiang; Zhang, Zheng; Ouyang, Xiaoping

2018-04-01

How to remove radionuclides from radioactive wastewater has long been a difficult problem, especially in nuclear accidents. In this paper, the adsorption of radionuclides Cs, Sr, and Ba on the monolayer MoS2 was investigated by using the first principles calculation method. Through the calculation of adsorption energy and Hirshfeld charge of the radionuclides on the monolayer MoS2 at six adsorption sites, the results show that all of the radionuclides chemisorbed on the monolayer MoS2, and the adsorption strength of these three kinds of radionuclides on the monolayer MoS2 is Ba > Sr > Cs. This work might shed some light on the treatment of the radioactive wastewater.

A Coincidence Signature Library for Multicoincidence Radionuclide Analysis Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Leon E.; Ellis, J E.; Valsan, Andrei B.

Pacific Northwest National Laboratory (PNNL) is currently developing multicoincidence systems to perform trace radionuclide analysis at or near the sample collection point, for applications that include emergency response, nuclear forensics, and environmental monitoring. Quantifying radionuclide concentrations with these systems requires a library of accurate emission intensities for each detected signature, for all candidate radionuclides. To meet this need, a Coincidence Lookup Library (CLL) is being developed to calculate the emission intensities of coincident signatures from a user-specified radionuclide, or conversely, to determine the radionuclides that may be responsible for a specific detected coincident signature. The algorithms used to generate absolutemore » emission intensities and various query modes for our developmental CLL are described.« less

Understanding Radionuclide Interactions with Layered Materials

NASA Astrophysics Data System (ADS)

Wang, Y.

2015-12-01

Layered materials play an important role in nuclear waste management and environmental cleanup. Better understanding of radionuclide interactions with those materials is critical for engineering high-performance materials for various applications. This presentation will provide an overview on radionuclide interactions with two general categories of layered materials - cationic clays and anionic clays - from a perspective of nanopore confinement. Nanopores are widely present in layered materials, either as the interlayers or as inter-particle space. Nanopore confinement can significantly modify chemical reactions in those materials. This effect may cause the preferential enrichment of radionuclides in nanopores and therefore directly impact the mobility of the radionuclides. This effect also implies that conventional sorption measurements using disaggregated samples may not represent chemical conditions in actual systems. The control of material structures on ion exchange, surface complexation, and diffusion in layered materials will be systematically examined, and the related modeling approaches will be discussed. This work was performed at Sandia National Laboratories, which is a multiprogram laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the DOE under contract DE-AC04-94AL8500.

Warm Up to a Good Sound

ERIC Educational Resources Information Center

Tovey, David C.

1977-01-01

Most choral directors in schools today have been exposed to a variety of warm-up procedures. Yet, many do not use the warm-up time effectively as possible. Considers the factors appropriate to a warm-up exercise and three basic warm-up categories. (Author/RK)

Gastroesophageal reflux demonstrated by hepatobiliary imaging in scleroderma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sawaf, N.W.; Orzel, J.A.; Weiland, F.L.

1987-03-01

Radionuclide hepatobiliary imaging was performed on a patient with a longstanding history of scleroderma who presented with abdominal pain suggestive of biliary disease. Cystic duct patency was documented after 10 min with tracer accumulation in the second portion of the duodenum which failed to progress consistent with the duodenal hypomotility of scleroderma. The patient was given intravenous Kinevac resulting in gastroesophageal reflux of radionuclide.

Breast Cancer Treatment in the Era of Molecular Imaging

PubMed Central

Edelhauser, Gundula; Funovics, Martin

2008-01-01

Summary Molecular imaging employs molecularly targeted probes to visualize and often quantify distinct disease-specific markers and pathways. Modalities like intravital confocal or multiphoton microscopy, near-infrared fluorescence combined with endoscopy, surface reflectance imaging, or fluorescence-mediated tomography, and radionuclide imaging with positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are increasingly used for small animal high-throughput screening, drug development and testing, and monitoring gene therapy experiments. In the clinical treatment of breast cancer, PET and SPECT as well as magnetic resonance-based molecular imaging are already established for the staging of distant disease and intrathoracic nodal status, for patient selection regarding receptor-directed treatments, and to gain early information about treatment efficacy. In the near future, reporter gene imaging during gene therapy and further spatial and qualitative characterization of the disease can become clinically possible with radionuclide and optical methods. Ultimately, it may be expected that every level of breast cancer treatment will be affected by molecular imaging, including screening. PMID:21048912

Committed warming inferred from observations

NASA Astrophysics Data System (ADS)

Mauritsen, Thorsten; Pincus, Robert

2017-09-01

Due to the lifetime of CO2, the thermal inertia of the oceans, and the temporary impacts of short-lived aerosols and reactive greenhouse gases, the Earth’s climate is not equilibrated with anthropogenic forcing. As a result, even if fossil-fuel emissions were to suddenly cease, some level of committed warming is expected due to past emissions as studied previously using climate models. Here, we provide an observational-based quantification of this committed warming using the instrument record of global-mean warming, recently improved estimates of Earth’s energy imbalance, and estimates of radiative forcing from the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Compared with pre-industrial levels, we find a committed warming of 1.5 K (0.9-3.6, 5th-95th percentile) at equilibrium, and of 1.3 K (0.9-2.3) within this century. However, when assuming that ocean carbon uptake cancels remnant greenhouse gas-induced warming on centennial timescales, committed warming is reduced to 1.1 K (0.7-1.8). In the latter case there is a 13% risk that committed warming already exceeds the 1.5 K target set in Paris. Regular updates of these observationally constrained committed warming estimates, although simplistic, can provide transparent guidance as uncertainty regarding transient climate sensitivity inevitably narrows and the understanding of the limitations of the framework is advanced.

System and method for assaying a radionuclide

DOEpatents

Cadieux, James R; King, III, George S; Fugate, Glenn A

2014-12-23

A system for assaying a radionuclide includes a liquid scintillation detector, an analyzer connected to the liquid scintillation detector, and a delay circuit connected to the analyzer. A gamma detector and a multi-channel analyzer are connected to the delay circuit and the gamma detector. The multi-channel analyzer produces a signal reflective of the radionuclide in the sample. A method for assaying a radionuclide includes selecting a sample, detecting alpha or beta emissions from the sample with a liquid scintillation detector, producing a first signal reflective of the alpha or beta emissions, and delaying the first signal a predetermined time. The method further includes detecting gamma emissions from the sample, producing a second signal reflective of the gamma emissions, and combining the delayed first signal with the second signal to produce a third signal reflective of the radionuclide.

Video instrumentation for radionuclide angiocardiography.

NASA Technical Reports Server (NTRS)

Kriss, J. P.

1973-01-01

Two types of videoscintiscopes for performing radioisotopic angiocardiography with a scintillation camera are described, and use of these instruments in performing clinical studies is illustrated. Radionuclide angiocardiography is a simple, quick and accurate procedure recommended as a screening test for patients with a variety of congenital and acquired cardiovascular lesions. When performed in conjunction with coronary arterial catheterization, dynamic radionuclide angiography may provide useful information about regional myocardial perfusion. Quantitative capabilities greatly enhance the potential of this diagnostic tool.

Evaluation of segmental left ventricular wall motion by equilibrium gated radionuclide ventriculography.

PubMed

Van Nostrand, D; Janowitz, W R; Holmes, D R; Cohen, H A

1979-01-01

The ability of equilibrium gated radionuclide ventriculography to detect segmental left ventricular (LV) wall motion abnormalities was determined in 26 patients undergoing cardiac catheterization. Multiple gated studies obtained in 30 degrees right anterior oblique and 45 degrees left anterior oblique projections, played back in a movie format, were compared to the corresponding LV ventriculograms. The LV wall in the two projections was divided into eight segments. Each segment was graded as normal, hypokinetic, akinetic, dyskinetic, or indeterminate. Thirteen percent of the segments in the gated images were indeterminate; 24 out of 27 of these were proximal or distal inferior wall segments. There was exact agreement in 86% of the remaining segments. The sensitivity of the radionuclide technique for detecting normal versus any abnormal wall motion was 71%, with a specificity of 99%. Equilibrium gated ventriculography is an excellent noninvasive technique for evaluating segmental LV wall motion. It is least reliable in assessing the proximal inferior wall and interventricular septum.

Military Implications of Global Warming.

DTIC Science & Technology

1999-05-20

U.S. environmental issues also have important global implications. This paper analyzes current U.S. Policy as it pertains to global warming and climate...for military involvement to reduce global warming . Global warming and other environmental issues are important to the U.S. military. As the United

The potential of two Salix genotypes for radionuclide/heavy metal accumulation. A case study of Rovinari ash pit (Gorj District, Romania)

NASA Astrophysics Data System (ADS)

Hernea, Cornelia; Neţoiu, Constantin; Corneanu, Gabriel; Crăciun, Constantin; Corneanu, Mihaela; Cojocaru, Luminiţa; Rovena Lăcătuşu, Anca; Popescu, Ion

2014-05-01

Thermo Electric Power Plants (TEPP) produce a high amount of ash, that contains heavy metals and radionuclides. Ash is usually stored in ash-pits, in mixture with water and contains U235, Th 234 and their decay products, that are released from the coal matrix, during combustion, as well as heavy metals. Warm weather dried the ash and it can be spread by the wind in surrounded area. This paper presents the results of an experiment with two Salix genotypes, cultivated on an old closed ash-pit, nearby the Rovinari TEPP, in the middle Jiu valley (Gorj District, Romania), in order to evaluate its tolerance to heavy metals and radionuclides. Ash analysis revealed the presence of natural radionuclides, beloging from ash and coal dust, as well as of Cs 137, of Chernobil provenance. Radionuclides content over the normal limits for Romania were registered for Th 234, Pb210, U235 and Ra226. The heavy metals level in ash was over the normal limits, but under the alerts limits. In order to establish the woody plants tolerance to heavy metals and radionuclides, it is important to study the seedlings behavior. In this respect Salix alba and Salix viminalis whips and cuttings culture have been establish on Rovinari ash-pit. The observations made on survival and growth rate pointed out the superiority of Salix viminalis behaviour. After a period of three years Salix viminalis registered a 96% survival rate, while in Salix alba annual decreases, reaching to 14%. These results are supported by the radionuclides content in leaves and by the electron microscopy studies. In Salix alba the leaves parenchimatic cells present a low sinthesis activity. The exogenous particles are accumulated in parenchima cells vacuola, the chloroplasts are usually agranal, with few starch grains and mitocondria presents slightly dillated crista. The ultrastructural features of the mature leaf cells, evidenced the natural adaptation of Salix viminalins for development in an environment with a big amount of

Considerations for Bioassay Monitoring of Mixtures of Radionuclides

DOE PAGES

Klumpp, John; Waters, Tom; Bertelli, Luiz

2017-10-01

Complying with regulations for bioassay monitoring of radionuclide intakes is significantly more complex for mixtures than it is for pure radionuclides. Different constituents will naturally have different dose coefficients, be detectable at significantly different levels, and may require very different amounts of effort to bioassay. The ability to use certain constituents as surrogates for others will depend on how well characterized the mixture is, as well as whether the employee is also working with other radionuclides. This is further compounded by the fact that the composition of a mixture (or even of a pure radionuclide) is likely to change overmore » time. Internal dosimetrists must decide how best to monitor employees who work with radionuclide mixtures. In particular, they must decide which constituents should be monitored routinely, which constituents only need to be monitored in the case of an intake, and how to estimate doses based on intakes of monitored and unmonitored constituents.« less

Feedback attribution of the land-sea warming contrast in a global warming simulation of the NCAR CCSM4

DOE PAGES

Sejas, Sergio A.; Albert, Oriene S.; Cai, Ming; ...

2014-12-02

One of the salient features in both observations and climate simulations is a stronger land warming than sea. This paper provides a quantitative understanding of the main processes that contribute to the land-sea warming asymmetry in a global warming simulation of the NCAR CCSM4. The CO 2 forcing alone warms the surface nearly the same for both land and sea, suggesting that feedbacks are responsible for the warming contrast. Our analysis on one hand confirms that the principal contributor to the above-unity land-to-sea warming ratio is the evaporation feedback; on the other hand the results indicate that the sensible heatmore » flux feedback has the largest land-sea warming difference that favors a greater ocean than land warming. Furthermore, the results uniquely highlight the importance of other feedbacks in establishing the above-unity land-to-sea warming ratio. Particularly, the SW cloud feedback and the ocean heat storage in the transient response are key contributors to the greater warming over land than sea.« less

Feedback attribution of the land-sea warming contrast in a global warming simulation of the NCAR CCSM4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sejas, Sergio A.; Albert, Oriene S.; Cai, Ming

One of the salient features in both observations and climate simulations is a stronger land warming than sea. This paper provides a quantitative understanding of the main processes that contribute to the land-sea warming asymmetry in a global warming simulation of the NCAR CCSM4. The CO 2 forcing alone warms the surface nearly the same for both land and sea, suggesting that feedbacks are responsible for the warming contrast. Our analysis on one hand confirms that the principal contributor to the above-unity land-to-sea warming ratio is the evaporation feedback; on the other hand the results indicate that the sensible heatmore » flux feedback has the largest land-sea warming difference that favors a greater ocean than land warming. Furthermore, the results uniquely highlight the importance of other feedbacks in establishing the above-unity land-to-sea warming ratio. Particularly, the SW cloud feedback and the ocean heat storage in the transient response are key contributors to the greater warming over land than sea.« less

Seven years of radionuclide laboratory at IMC - important achievements.

PubMed

Hrubý, M; Kučka, J; Pánek, J; Štěpánek, P

2016-10-20

For many important research topics in polymer science the use of radionuclides brings significant benefits concerning nanotechnology, polymer drug delivery systems, tissue engineering etc. This contribution describes important achievements of the radionuclide laboratory at Institute of Macromolecular Chemistry of the Academy of Sciences of the Czech Republic (IMC) in the area of polymers for biomedical applications. Particular emphasis will be given to water-soluble polymer carriers of radionuclides, thermoresponsive polymer radionuclide carriers, thermoresponsive polymers for local brachytherapy, polymer scaffolds modified with (radiolabeled) peptides and polymer copper chelators for the therapy of Wilson´s disease.

Radionuclide Imaging Technologies for Biological Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howell, Calvin R.; Reid, Chantal D.; Weisenberger, Andrew G.

2014-05-14

The main objective of this project is to develop technologies and experimental techniques for studying the dynamics of physiological responses of plants to changes in their interface with the local environment and to educate a new generation of scientists in an interdisciplinary environment of biology, physics and engineering. Also an important goal is to perform measurements to demonstrate the new data that can be produced and made available to the plant-biology community using the imaging technologies and experimental techniques developed in this project. The study of the plant-environment interface includes a wide range of topics in plant physiology, e.g., themore » root-soil interface, resource availability, impact of herbivores, influence of microbes on root surface, and responses to toxins in the air and soil. The initial scientific motivation for our work is to improve understanding of the mechanisms for physiological responses to abrupt changes in the local environment, in particular, the responses that result in short-term adjustments in resource (e.g., sugars, nutrients and water) allocations. Data of time-dependent responses of plants to environmental changes are essential in developing mechanistic models for substance intake and resource allocation. Our approach is to use radioisotope tracing techniques to study whole-plant and plant organ (e.g., leaves, stems, roots) dynamical responses to abrupt changes in environmental conditions such as concentration of CO 2 in the atmosphere, nutrient availability and lighting. To this aim we are collaborating with the Radiation Detector and Imaging Group at the Thomas Jefferson National Laboratory Facility (JLab) to develop gamma-ray and beta particle imaging systems optimized for plant studies. The radioisotope tracing measurements are conducted at the Phytotron facility at Duke University. The Phytotron is a controlled environment plant research facility with a variety of plant growth chambers. One chamber is

21 CFR 892.5730 - Radionuclide brachytherapy source.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide brachytherapy...

Irrigation enhances local warming with greater nocturnal warming effects than daytime cooling effects

NASA Astrophysics Data System (ADS)

Chen, Xing; Jeong, Su-Jong

2018-02-01

To meet the growing demand for food, land is being managed to be more productive using agricultural intensification practices, such as the use of irrigation. Understanding the specific environmental impacts of irrigation is a critical part of using it as a sustainable way to provide food security. However, our knowledge of irrigation effects on climate is still limited to daytime effects. This is a critical issue to define the effects of irrigation on warming related to greenhouse gases (GHGs). This study shows that irrigation led to an increasing temperature (0.002 °C year-1) by enhancing nighttime warming (0.009 °C year-1) more than daytime cooling (-0.007 °C year-1) during the dry season from 1961-2004 over the North China Plain (NCP), which is one of largest irrigated areas in the world. By implementing irrigation processes in regional climate model simulations, the consistent warming effect of irrigation on nighttime temperatures over the NCP was shown to match observations. The intensive nocturnal warming is attributed to energy storage in the wetter soil during the daytime, which contributed to the nighttime surface warming. Our results suggest that irrigation could locally amplify the warming related to GHGs, and this effect should be taken into account in future climate change projections.

Radiolabeled Adenoviral Sub-unit Proteins for Molecular Imaging and Therapeutic Applications in Oncology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Srivastava, S.; Meinken, G.; Springer, K. Awasthi, V.

2004-10-06

The objective of this project was to develop and optimize new ligand systems, based on adenoviral vectors (intact adenovirus, adeno-viral fiber protein, and the knob protein), for delivering suitable radionuclides into tumor cells for molecular imaging and combined gene/radionuclide therapy of cancer.

ECAT: A New Computerized Tomographic Imaging System for Position-Emitting Radiopharmaceuticals

DOE R&D Accomplishments Database

Phelps, M. E.; Hoffman, E. J.; Huang, S. C.; Kuhl, D. E.

1977-01-01

The ECAT was designed and developed as a complete computerized positron radionuclide imaging system capable of providing high contrast, high resolution, quantitative images in 2 dimensional and tomographic formats. Flexibility, in its various image mode options, allows it to be used for a wide variety of imaging problems.

Pediatric radiation dosimetry for positron-emitting radionuclides using anthropomorphic phantoms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, Tianwu; Bolch, Wesley E.; Lee, Choonsik

2013-10-15

Purpose: Positron emission tomography (PET) plays an important role in the diagnosis, staging, treatment, and surveillance of clinically localized diseases. Combined PET/CT imaging exhibits significantly higher sensitivity, specificity, and accuracy than conventional imaging when it comes to detecting malignant tumors in children. However, the radiation dose from positron-emitting radionuclide to the pediatric population is a matter of concern since children are at a particularly high risk when exposed to ionizing radiation.Methods: The authors evaluate the absorbed fractions and specific absorbed fractions (SAFs) of monoenergy photons/electrons as well as S-values of 9 positron-emitting radionuclides (C-11, N-13, O-15, F-18, Cu-64, Ga-68, Rb-82,more » Y-86, and I-124) in 48 source regions for 10 anthropomorphic pediatric hybrid models, including the reference newborn, 1-, 5-, 10-, and 15-yr-old male and female models, using the Monte Carlo N-Particle eXtended general purpose Monte Carlo transport code.Results: The self-absorbed SAFs and S-values for most organs were inversely related to the age and body weight, whereas the cross-dose terms presented less correlation with body weight. For most source/target organ pairs, Rb-82 and Y-86 produce the highest self-absorbed and cross-absorbed S-values, respectively, while Cu-64 produces the lowest S-values because of the low-energy and high-frequency of electron emissions. Most of the total self-absorbed S-values are contributed from nonpenetrating particles (electrons and positrons), which have a linear relationship with body weight. The dependence of self-absorbed S-values of the two annihilation photons varies to the reciprocal of 0.76 power of the mass, whereas the self-absorbed S-values of positrons vary according to the reciprocal mass.Conclusions: The produced S-values for common positron-emitting radionuclides can be exploited for the assessment of radiation dose delivered to the pediatric population from

21 CFR 892.5740 - Radionuclide teletherapy source.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide teletherapy source. 892.5740 Section 892.5740 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5740 Radionuclide teletherapy source...

21 CFR 892.1360 - Radionuclide dose calibrator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide dose calibrator. 892.1360 Section 892.1360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1360 Radionuclide dose calibrator. (a...

Hetero-bivalent Imaging Agents for Simultaneous Targeting Prostate-Specific Membrane Antigen (PSMA) and Hepsin

DTIC Science & Technology

2012-09-01

functions of PSMA for PCa, we have designed and prepared PSMA-based imaging probes to evaluate its biological activity in vivo in a variety of...nucleophilic functional group to be coupled with radionuclides, i.e., 125I or 18F, or optical dyes. C. Accomplishments in Year 2 1...position of the lysine or N-terminus isoleucine with the imaging prosthetic groups such as optical dyes and radionuclides. The alloc group was

TOPEX/El Nino Watch - Warm Water Pool is Thinning, Feb, 5, 1998

NASA Technical Reports Server (NTRS)

1998-01-01

This image of the Pacific Ocean was produced using sea surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Feb. 5, 1998 and sea surface height is an indicator of the heat content of the ocean. The area and volume of the El Nino warm water pool that is affecting global weather patterns remains extremely large, but the pool has thinned along the equator and near the coast of South America. This 'thinning' means that the warm water is not as deep as it was a few months ago. Oceanographers indicate this is a classic pattern, typical of a mature El Nino condition that they would expect to see during the ocean's gradual transition back to normal sea level. In this image, the white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal; in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level. The El Nino phenomenon is thought to be triggered when the steady westward blowing trade winds weaken and even reverse direction. This change in the winds allows a large mass of warm water (the red and white area) that is normally located near Australia to move eastward along the equator until it reaches the coast of South America. The displacement of so much warm water affects evaporation, where rain clouds form and, consequently, alters the typical atmospheric jet stream patterns around the world. Using satellite imagery, buoy and ship data, and a forecasting model of the ocean-atmosphere system, the National Oceanic and Atmospheric Administration, (NOAA), has continued to issue an advisory indicating the so-called El Nino weather conditions that have impacted much of the United States and the world are expected to remain through

Warm-up and performance in competitive swimming.

PubMed

Neiva, Henrique P; Marques, Mário C; Barbosa, Tiago M; Izquierdo, Mikel; Marinho, Daniel A

2014-03-01

Warm-up before physical activity is commonly accepted to be fundamental, and any priming practices are usually thought to optimize performance. However, specifically in swimming, studies on the effects of warm-up are scarce, which may be due to the swimming pool environment, which has a high temperature and humidity, and to the complexity of warm-up procedures. The purpose of this study is to review and summarize the different studies on how warming up affects swimming performance, and to develop recommendations for improving the efficiency of warm-up before competition. Most of the main proposed effects of warm-up, such as elevated core and muscular temperatures, increased blood flow and oxygen delivery to muscle cells and higher efficiency of muscle contractions, support the hypothesis that warm-up enhances performance. However, while many researchers have reported improvements in performance after warm-up, others have found no benefits to warm-up. This lack of consensus emphasizes the need to evaluate the real effects of warm-up and optimize its design. Little is known about the effectiveness of warm-up in competitive swimming, and the variety of warm-up methods and swimming events studied makes it difficult to compare the published conclusions about the role of warm-up in swimming. Recent findings have shown that warm-up has a positive effect on the swimmer's performance, especially for distances greater than 200 m. We recommend that swimmers warm-up for a relatively moderate distance (between 1,000 and 1,500 m) with a proper intensity (a brief approach to race pace velocity) and recovery time sufficient to prevent the early onset of fatigue and to allow the restoration of energy reserves (8-20 min).

Cyclotron Production of Radionuclides for Nuclear Medicine at Academic Centers

NASA Astrophysics Data System (ADS)

Lapi, Suzanne

2016-09-01

The increase in use of radioisotopes for medical imaging has led to the development of new accelerator targetry and separation techniques for isotope production. For example, the development of longer-lived position emitting radionuclides has been explored to allow for nuclear imaging agents based on peptides, antibodies and nanoparticles. These isotopes (64Cu, 89Zr, 86Y) are typically produced via irradiation of solid targets on smaller cyclotrons (10-25 MeV) at academic or hospital based facilities. Recent research has further expanded the toolbox of PET tracers to include additional isotopes such as 52Mn, 55Co, 76Br and others. The smaller scale of these types of facilities can enable the straightforward involvement of students, thus adding to the next generation of nuclear science leaders. Research pertaining to development of robust and larger scale production technologies including solid target systems and remote systems for transport and purification of these isotopes has enabled both preclinical and clinical imaging research for many diseases. In particular, our group has focused on the use of radiolabeled antibodies for imaging of receptor expression in preclinical models and in a clinical trial of metastatic breast cancer patients.

Detection of urinary extravasation by delayed technetium-99m DTPA renal imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taki, J.; Tonami, N.; Aburano, T.

Delayed imaging with Tc-99m DTPA renal scintigraphy demonstrated urinary extravasation in a patient with acute anuria in whom early sequential imaging showed no abnormal extrarenal radionuclide accumulation.

Natural and anthropogenic radionuclide activity concentrations in the New Zealand diet.

PubMed

Pearson, Andrew J; Gaw, Sally; Hermanspahn, Nikolaus; Glover, Chris N

2016-01-01

To support New Zealand's food safety monitoring regime, a survey was undertaken to establish radionuclide activity concentrations across the New Zealand diet. This survey was undertaken to better understand the radioactivity content of the modern diet and also to assess the suitability of the current use of milk as a sentinel for dietary radionuclide trends. Thirteen radionuclides were analysed in 40 common food commodities, including animal products, fruits, vegetables, cereal grains and seafood. Activity was detected for (137)Caesium, (90)Strontium and (131)Iodine. No other anthropogenic radionuclides were detected. Activity concentrations of the three natural radionuclides of Uranium and the daughter radionuclide (210)Polonium were detected in the majority of food sampled, with a large variation in magnitude. The maximum activity concentrations were detected in shellfish for all these radionuclides. Based on the established activity concentrations and ranges, the New Zealand diet contains activity concentrations of anthropogenic radionuclides far below the Codex Alimentarius guideline levels. Activity concentrations obtained for milk support its continued use as a sentinel for monitoring fallout radionuclides in terrestrial agriculture. The significant levels of natural and anthropogenic radionuclide activity concentrations detected in finfish and molluscs support undertaking further research to identify a suitable sentinel for New Zealand seafood monitoring. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Recent Warming of Lake Kivu

PubMed Central

Katsev, Sergei; Aaberg, Arthur A.; Crowe, Sean A.; Hecky, Robert E.

2014-01-01

Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient. PMID:25295730

Recent warming of lake Kivu.

PubMed

Katsev, Sergei; Aaberg, Arthur A; Crowe, Sean A; Hecky, Robert E

2014-01-01

Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient.

49 CFR 173.433 - Requirements for determining basic radionuclide values, and for the listing of radionuclides on...

Code of Federal Regulations, 2014 CFR

2014-10-01

... § 173.435 or § 173.436 or for which no relevant data are available: (1) the radionuclide values in... package must satisfy: ER26JA04.001 Where: B(i) is the activity of radionuclide i in special form; and A1... activity which may be transported in a Type A package must satisfy: ER26JA04.002 Where: C(j) is the...

Monitoring release of disposable radionuclides in the Kara sea: Bioaccumulation of long-lived radionuclides in echinoderms and molluscs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisher, N.S.

1994-01-01

The objective of the present proposal is to continue and extend our research on the trophic transfer of important radionuclides in benthic fauna of the Kara Sea. This project is assessing the extent to which select species of seastars, brittle stars, and clams typical of the Kara Sea concentrate and retain a variety of long-lived radionuclides known to be (or suspected to be) present in the disposed wastes in the Russian Arctic. The rates and routes of uptake and depuration of isotopes in the same or in closely related species are being quantified so that endemic benthic organisms can bemore » assessed as potential bioindicators of released radionuclides in Arctic waters.« less

Colloid-facilitated radionuclide transport: a regulatory perspective

NASA Astrophysics Data System (ADS)

Dam, W. L.; Pickett, D. A.; Codell, R. B.; Nicholson, T. J.

2001-12-01

What hydrogeologic-geochemical-microbial conditions and processes affect migration of radionuclides sorbed onto microparticles or native colloid-sized radionuclide particles? The U.S. Nuclear Regulatory Commission (NRC) is responsible for protecting public health, safety, and the environment at numerous nuclear facilities including a potential high-level nuclear waste disposal site. To fulfill these obligations, NRC needs to understand the mechanisms controlling radionuclide release and transport and their importance to performance. The current focus of NRC staff reviews and technical interactions dealing with colloid-facilitated transport relates to the potential nuclear-waste repository at Yucca Mountain, Nevada. NRC staff performed bounding calculations to quantify radionuclide releases available for ground-water transport to potential receptors from a Yucca Mountain repository. Preliminary analyses suggest insignificant doses of plutonium and americium colloids could be derived from spent nuclear fuel. Using surface complexation models, NRC staff found that colloids can potentially lower actinide retardation factors by up to several orders of magnitude. Performance assessment calculations, in which colloidal transport of plutonium and americium was simulated by assuming no sorption or matrix diffusion, indicated no effect of colloids on human dose within the 10,000 year compliance period due largely to long waste-package lifetimes. NRC staff have identified information gaps and developed technical agreements with the U.S. Department of Energy (DOE) to ensure sufficient information will be presented in any potential future Yucca Mountain license application. DOE has agreed to identify which radionuclides could be transported via colloids, incorporate uncertainties in colloid formation, release and transport parameters, and conceptual models, and address the applicability of field data using synthetic microspheres as colloid analogs. NRC is currently

G-warm inflation

NASA Astrophysics Data System (ADS)

Herrera, Ramón

2017-05-01

A warm inflationary universe in the context of Galileon model or G-model is studied. Under a general formalism we study the inflationary dynamics and the cosmological perturbations considering a coupling of the form G(phi,X)=g(phi) X. As a concrete example, we consider an exponential potential together with the cases in which the dissipation and Galilean coefficients are constants. Also, we study the weak regime given by the condition R<1+3gHdot phi, and the strong regime in which 1warm inflation, assuming the condition for warm inflation in which the temperature T>H, the conditions or the weak and strong regimes, together with the consistency relation r=r(ns) from Planck data.

A joint procedural position statement on imaging in cardiac sarcoidosis: from the Cardiovascular and Inflammation & Infection Committees of the European Association of Nuclear Medicine, the European Association of Cardiovascular Imaging, and the American Society of Nuclear Cardiology.

PubMed

2017-10-01

This joint position paper illustrates the role and the correct use of echocardiography, radionuclide imaging with 18F-fluorodeoxyglucose positron emission tomography, radionuclide myocardial perfusion imaging and cardiovascular magnetic resonance imaging for the evaluation and management of patients with known or suspected cardiac sarcoidosis. This position paper will aid in standardizing imaging for cardiac sarcoidosis and may facilitate clinical trials and pooling of multi-centre data on cardiac sarcoidosis. Proposed flow charts for the work up and management of cardiac sarcoidosis are included. Copyright © 2017 European Association of Nuclear Medicine, the European Association of Cardiovascular Imaging, and the American Society of Nuclear Cardiology.

A Novel Ideal Radionuclide Imaging System for Non-invasively Cell Monitoring built on Baculovirus Backbone by Introducing Sleeping Beauty Transposon

PubMed Central

Lv, Jing; Pan, Yu; Ju, Huijun; Zhou, Jinxin; Cheng, Dengfeng; Shi, Hongcheng; Zhang, Yifan

2017-01-01

Sleeping Beauty (SB) transposon is an attractive tool in stable transgene integration both in vitro and in vivo; and we introduced SB transposon into recombinant sodium-iodide symporter baculovirus system (Bac-NIS system) to facilitate long-term expression of recombinant sodium-iodide symporter. In our study, two hybrid baculovirus systems (Bac-eGFP-SB-NeoR and Bac-NIS-SB-NeoR) were successfully constructed and used to infect U87 glioma cells. After G418 selection screening, the Bac-eGFP-SB-NeoR-U87 cells remained eGFP positive, at the 18th and 196th day post transfection (96.03 ± 0.21% and 97.43 ± 0.81%), while eGFP positive population declined significantly at 18 days in cells transfected with unmodified baculovirus construct. NIS gene expression by Bac-NIS-SB-NeoR-U87 cells was also maintained for 28 weeks as determined by radioiodine uptake assay, reverse transcription-polymerase chain reaction (RT-PCR) and Western Blot (WB) assay. When transplanted in mice, Bac-NIS-SB-NeoR-U87 cells also expressed NIS gene stably as monitored by SPECT imaging for 43 days until the tumor-bearing mice were sacrificed. Herein, we showed that incorporation of SB in Bac-NIS system (hybrid Bac-NIS-SB-NeoR) can achieve a long-term transgene expression and can improve radionuclide imaging in cell tracking and monitoring in vivo. PMID:28262785

A random walk model to simulate the atmospheric dispersion of radionuclide

NASA Astrophysics Data System (ADS)

Zhuo, Jun; Huang, Liuxing; Niu, Shengli; Xie, Honggang; Kuang, Feihong

2018-01-01

To investigate the atmospheric dispersion of radionuclide in large-medium scale, a numerical simulation method based on random walk model for radionuclide atmospheric dispersion was established in the paper. The route of radionuclide migration and concentration distribution of radionuclide can be calculated out by using the method with the real-time or historical meteorological fields. In the simulation, a plume of radionuclide is treated as a lot of particles independent of each other. The particles move randomly by the fluctuations of turbulence, and disperse, so as to enlarge the volume of the plume and dilute the concentration of radionuclide. The dispersion of the plume over time is described by the variance of the particles. Through statistical analysis, the relationships between variance of the particles and radionuclide dispersion characteristics can be derived. The main mechanisms considered in the physical model are: (1) advection of radionuclide by mean air motion, (2) mixing of radionuclide by atmospheric turbulence, (3) dry and wet deposition, (4) disintegration. A code named RADES was developed according the method. And then, the European Tracer Experiment (ETEX) in 1994 is simulated by the RADES and FLEXPART codes, the simulation results of the concentration distribution of tracer are in good agreement with the experimental data.

Attenuation of radionuclide activity by metal-cup arthroplasties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenthall, L.; Rosenthall, S.

1985-04-01

The half-value layers of stainless steel, bone cement, and polyethylene were measured for /sup 99m/Tc, /sup 67/Ga, /sup 111/In, and /sup 201/TI to render some insight into the attenuating effects of the metallic cup and other components used in surface-replacement revision arthroplasty. On theoretic consideration, a twofold increase in /sup 99m/Tc-methylene diphosphonate in bone inside the cup should not be attenuated to the point of escaping detection on the radionuclide images of the hip. /sup 67/Ga, using the 184 and 300 keV peaks, and /sup 111/In have greater half-value layers than /sup 99m/Tc and are subject to less attenuation bymore » the metallic cup.« less

Global warming and obesity: a systematic review.

PubMed

An, R; Ji, M; Zhang, S

2018-02-01

Global warming and the obesity epidemic are two unprecedented challenges mankind faces today. A literature search was conducted in the PubMed, Web of Science, EBSCO and Scopus for articles published until July 2017 that reported findings on the relationship between global warming and the obesity epidemic. Fifty studies were identified. Topic-wise, articles were classified into four relationships - global warming and the obesity epidemic are correlated because of common drivers (n = 21); global warming influences the obesity epidemic (n = 13); the obesity epidemic influences global warming (n = 13); and global warming and the obesity epidemic influence each other (n = 3). We constructed a conceptual model linking global warming and the obesity epidemic - the fossil fuel economy, population growth and industrialization impact land use and urbanization, motorized transportation and agricultural productivity and consequently influences global warming by excess greenhouse gas emission and the obesity epidemic by nutrition transition and physical inactivity; global warming also directly impacts obesity by food supply/price shock and adaptive thermogenesis, and the obesity epidemic impacts global warming by the elevated energy consumption. Policies that endorse deployment of clean and sustainable energy sources, and urban designs that promote active lifestyles, are likely to alleviate the societal burden of global warming and obesity. © 2017 World Obesity Federation.

Pinhole imaging in Legg-Perthes disease: further observations.

PubMed

Danigelis, J A

1976-01-01

Fifty-nine patients with Legg-Perthes disease and 12 others were studied using 99mTc-polyphosphate and the pinhole collimator imaging technique. Radiographs of both hips were correlated with images in each patient. In the Legg-Perthes patients, a radionuclide uptake deficiency of variable size was observed in the proximal femoral epiphysis (EOC), which we believe is related to varying degrees of impaired blood supply. During later disease stages, adjacent zones of increased radionuclide activity of revascularization were observed that would replace the uptake defect eventually. Unless radiographic evidence of new bone formation was observed in the EOC, it was impossible to predict either the presence or extent of revascularization until bone imaging was done. Those patients with revascularization activity in the EOC exhibited a relatively short time interval (average, 3.2 months) before evidence of new bone formation radiographically. Others with increased radionuclide concentration limited to the growth plate and/or metaphysis averaged a much longer 7.8 months. In two patients there was a reversal of the initially increased activity in the growth plate, suggesting another vascular insult. There were no false-negative bone-image findings in the 12 cases that clinically and/or radiologically simulated Legg-Perthes disease. Our image studies correlate well with published histopathologic investigations, indicating to us that assessment of extent of pathologic involvement and of the disease course is facilitated by this technique. Subsequently, this could influence treatment selection and provide a more objective baseline from which to judge treatment results. Continued experience suggests pinhole bone imaging has useful clinical application in Legg-Perthes disease and other childhood hip disorders.

Increasing occurrence of cold and warm extremes during the recent global warming slowdown.

PubMed

Johnson, Nathaniel C; Xie, Shang-Ping; Kosaka, Yu; Li, Xichen

2018-04-30

The recent levelling of global mean temperatures after the late 1990s, the so-called global warming hiatus or slowdown, ignited a surge of scientific interest into natural global mean surface temperature variability, observed temperature biases, and climate communication, but many questions remain about how these findings relate to variations in more societally relevant temperature extremes. Here we show that both summertime warm and wintertime cold extreme occurrences increased over land during the so-called hiatus period, and that these increases occurred for distinct reasons. The increase in cold extremes is associated with an atmospheric circulation pattern resembling the warm Arctic-cold continents pattern, whereas the increase in warm extremes is tied to a pattern of sea surface temperatures resembling the Atlantic Multidecadal Oscillation. These findings indicate that large-scale factors responsible for the most societally relevant temperature variations over continents are distinct from those of global mean surface temperature.

TOPEX/El Nino Watch - Warm Water Pool is Increasing, Nov. 10, 1997

NASA Technical Reports Server (NTRS)

1997-01-01

This image of the Pacific Ocean was produced using sea surface height measurements taken by the U.S./French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Nov. 10, 1997. The volume of extra warm surface water (shown in white) in the core of the El Nino continues to increase, especially in the area between 15 degrees south latitude and 15 degrees north latitude in the eastern Pacific Ocean. The area of low sea level (shown in purple) has decreased somewhat from late October. The white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 centimeters and 32 cm (6 inches to 13 inches) above normal; in the red areas, it is about 10 centimeters (4 inches) above normal. The surface area covered by the warm water mass is about one-and-one-half times the size of the continental United States. The added amount of oceanic warm water near the Americas, with a temperature between 21 to 30 degrees Celsius (70 to 85 degrees Fahrenheit), is about 30 times the volume of water in all the U.S. Great Lakes combined. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level.

The El Nino phenomenon is thought to be triggered when the steady westward blowing trade winds weaken and even reverse direction. This change in the winds allows a large mass of warm water (the red and white areas) that is normally located near Australia to move eastward along the equator until it reaches the coast of South America. The displacement of so much warm water affects evaporation, where rain clouds form and, consequently, alters the typical atmospheric jet stream patterns around the world. Using these global data, limited regional measurements from buoys and ships, and a forecasting model of the ocean-atmospheric system, the National Centers for Environmental Prediction (NCEP) of the National Oceanic and

Radionuclides, radiotracers and radiopharmaceuticals for in vivo diagnosis

NASA Astrophysics Data System (ADS)

Wiebe, Leonard I.

Radioactive tracers for in vivo clinical diagnosis fall within a narrow, strictly-defined set of specifications in respect of their physical properties, chemical and biochemical characteristics, and (approved) medical applications. The type of radioactive decay and physical half-life of the radionuclide are immutable properties which, along with the demands of production and supply, limit the choice of radionuclides used in medicine to only a small fraction of those known to exist. In use, the biochemical and physiological properties of a radiotracer are dictated by the chemical form of the radionuclide. This chemical form may range from elemental, molecular or ionic, to complex compounds formed by coordinate or covalent bonding of the radionuclide to either simple organic or inorganic molecules, or complex macromolecules. Few of the radiotracers which are tested in model systems ever become radiopharmaceuticals in the strictest sense. Radionuclides, radiotracers and radiopharmaceuticals in use are reviewed. Drug legislation and regulations concerning drug manufacture, as well as hospital ethical constraints and legislation concerning unsealed sources of radiation must all be satisfied in order to translate a radiopharmaceutical from the laboratory to clinical use.

Dynamics and transformations of radionuclides in soils and ecosystem health

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fellows, Robert J.; Ainsworth, Calvin C.; Driver, Crystal J.

1998-12-01

The chemical behavior of radionuclides can vary widely in soil and sediment environments. Equally important, for a given radionuclide the physico-chemical properties of the solids and aqueous phase can greatly influence a radionuclides behavior. Radionuclides can conceivably occur in soils as soluble-free, inorganic-soluble-complexed, organic-soluble, complexed, adsorbed, precipitated, coprecipitated, or solid structural species. While it is clear that an assessment of a radionuclide?s soil chemistry and potential shifts in speciation will yield a considerable understanding of its behavior in the natural environment, it does not directly translate to bioavailability or its impact on ecosystems health. The soil chemical factors have tomore » be linked to food chain considerations and other ecological parameters that directly tie to an analysis of ecosystem health. In general, the movement of radionuclides from lower to higher trophic levels diminishes with each trophic level in both aqua tic and terrestrial systems. In some cases, transfer is limited because of low absorption/assimilation by successive trophic organisms (Pu, U); for other radionuclides (Tc, H) assimilation may be high but rapid metabolic turnover and low retention greatly reduce tissue concentrations available to predator species. Still others are chemical analogs of essential elements whose concentrations are maintained under strict metabolic control in tissues (Cs) or are stored in tissues seldom consumed by other organisms (Sr storage in exoskeleton, shells, and bone). Therefore, the organisms that receive the greatest ingestion exposures are those in lower trophic positions or are in higher trophic levels but within simple, short food chains. Food source, behavior, and habitat influence the accumulation of radionuclides in animals.« less

Investigating warming trends and spatial patterns of Land Surface Temperatures over the Greater Los Angeles Area using new MODIS and VIIRS LST products

NASA Astrophysics Data System (ADS)

Malakar, N. K.; Hulley, G. C.

2016-12-01

The Los Angeles (LA) metropolitan area is one of the fastest growing urban centers in the United States, and home to roughly 18 million people. Understanding the trends and impacts of warming temperatures in urban environments is an increasingly important issue in our changing climate. We used thermal infrared data from Moderate Resolution Imaging Spectroradiometer (MODIS), and Visible Infrared Imaging Radiometer Suite (VIIRS) sensors to retrieve Land Surface Temperature using a new Temperature Emissivity Separation algorithm adapted for these sensors. We analyzed day and night LST retrievals to study the warming trends of LST for the greater LA region from 2002-2015. The average warming trend over LA for summer days and nights over this period for MODIS Aqua data was 1.1 °C per decade, while a more rapid warming is observed for the years 2012-2016 for both MODIS and VIIRS observations. We have also found that inland LA regions are warming more rapidly than the other regions. We further investigate the underlying cause of the warming by looking into the physical factors such as changes in net radiation, cloud cover, and evapotranspiration. The results will help to understand how indicators of climate change are evolving in the beginning of the 21st century, and how they compare with global climate model projections. Identification of potential impacts, and underlying causes of warming trends in various LA regions will help decision makers to develop policies to help mitigate the effects of rising temperatures.

Authropogenic Warming in North Alaska?.

NASA Astrophysics Data System (ADS)

Michaels, Patrick J.; Sappington, David E.; Stooksbury, David E.

1988-09-01

Using permafrost boreholes, Lachenbruch and Marshall recently reported evidence for a 2°-4°C warming in North Alaska occurring at some undetermined time during the last century. Popular accounts suggest their findings are evidence for anthropogenic warming caused by trace gases. Analyses of North Alaskan 1000-500 mb thickness onwards back to 1948 indicate that the warming was prior to that date. Relatively sparse thermometric data for the early twentieth century from Jones et al. are too noisy to support any trend since the data record begins in 1910, or to apply to any subperiod of climatic significance. Any warming detected from the permafrost record therefore occurred before the major emissions of thermally active trace gases.

Global warming

NASA Astrophysics Data System (ADS)

Houghton, John

2005-06-01

'Global warming' is a phrase that refers to the effect on the climate of human activities, in particular the burning of fossil fuels (coal, oil and gas) and large-scale deforestation, which cause emissions to the atmosphere of large amounts of 'greenhouse gases', of which the most important is carbon dioxide. Such gases absorb infrared radiation emitted by the Earth's surface and act as blankets over the surface keeping it warmer than it would otherwise be. Associated with this warming are changes of climate. The basic science of the 'greenhouse effect' that leads to the warming is well understood. More detailed understanding relies on numerical models of the climate that integrate the basic dynamical and physical equations describing the complete climate system. Many of the likely characteristics of the resulting changes in climate (such as more frequent heat waves, increases in rainfall, increase in frequency and intensity of many extreme climate events) can be identified. Substantial uncertainties remain in knowledge of some of the feedbacks within the climate system (that affect the overall magnitude of change) and in much of the detail of likely regional change. Because of its negative impacts on human communities (including for instance substantial sea-level rise) and on ecosystems, global warming is the most important environmental problem the world faces. Adaptation to the inevitable impacts and mitigation to reduce their magnitude are both necessary. International action is being taken by the world's scientific and political communities. Because of the need for urgent action, the greatest challenge is to move rapidly to much increased energy efficiency and to non-fossil-fuel energy sources.

Method for preparing radionuclide-labeled chelating agent-ligand complexes

DOEpatents

Meares, Claude F.; Li, Min; DeNardo, Sally J.

1999-01-01

Radionuclide-labeled chelating agent-ligand complexes that are useful in medical diagnosis or therapy are prepared by reacting a radionuclide, such as .sup.90 Y or .sup.111 In, with a polyfunctional chelating agent to form a radionuclide chelate that is electrically neutral; purifying the chelate by anion exchange chromatography; and reacting the purified chelate with a targeting molecule, such as a monoclonal antibody, to form the complex.

New best estimates for radionuclide solid-liquid distribution coefficients in soils. Part 2: naturally occurring radionuclides.

PubMed

Vandenhove, H; Gil-García, C; Rigol, A; Vidal, M

2009-09-01

Predicting the transfer of radionuclides in the environment for normal release, accidental, disposal or remediation scenarios in order to assess exposure requires the availability of an important number of generic parameter values. One of the key parameters in environmental assessment is the solid liquid distribution coefficient, K(d), which is used to predict radionuclide-soil interaction and subsequent radionuclide transport in the soil column. This article presents a review of K(d) values for uranium, radium, lead, polonium and thorium based on an extensive literature survey, including recent publications. The K(d) estimates were presented per soil groups defined by their texture and organic matter content (Sand, Loam, Clay and Organic), although the texture class seemed not to significantly affect K(d). Where relevant, other K(d) classification systems are proposed and correlations with soil parameters are highlighted. The K(d) values obtained in this compilation are compared with earlier review data.

Radionuclide speciation in effluent from La Hague reprocessing plant in France.

PubMed

Salbu, B; Skipperud, L; Germain, P; Guéguéniat, P; Strand, P; Lind, O C; Christensen, G

2003-09-01

Effluent from the La Hague nuclear fuel reprocessing plant was mixed with seawater in order to investigate the fate of the various radionuclides. Thus, a major objective of the present work is to characterize the effluent from La Hague reprocessing plant and to study how the radionuclide speciation changes with time when discharged into the marine environment. Discharges from the La Hague nuclear reprocessing plant represent an important source of artificially produced radionuclides to the North Sea. The transport, distribution, and biological uptake of radionuclides in the marine environment depends, however, on the physicochemical forms of radionuclides in the discharged effluents and on transformation processes that occur after entering the coastal waters. Information of these processes is needed to understand the transport and long-term distribution of the radionuclides. In the present work, a weekly discharged effluent from the nuclear fuel reprocessing plant at Cap La Hague in France was mixed with coastal water and fractionated with respect to particle size and charged species using ultra centrifugation and hollow fiber ultrafiltration with on line ion exchange. The size distribution pattern of gamma-emitting radionuclides was followed during a 62-h period after mixing the effluent with seawater. 54Mn was present as particulate material in the effluent, while other investigated radionuclides were discharged in a more mobile form or were mobilized after mixing with sea water (e.g., 60Co) and can be transported long distances in the sea. Sediments can act as a sink for less mobile discharged radionuclides (Skipperud et al. 2000). A kinetic model experiment was performed to provide information of the time-dependent distribution coefficients, Kd (t). The retention of the effluent radionuclides in sediments was surprisingly low (Kd 20-50), and the sediments acted as a poor sink for the released radionuclides. Due to the presence of non-reacting radionuclide

Multi-species collapses at the warm edge of a warming sea

PubMed Central

Rilov, Gil

2016-01-01

Even during the current biodiversity crisis, reports on population collapses of highly abundant, non-harvested marine species were rare until very recently. This is starting to change, especially at the warm edge of species’ distributions where populations are more vulnerable to stress. The Levant basin is the southeastern edge of distribution of most Mediterranean species. Coastal water conditions are naturally extreme, and are fast warming, making it a potential hotspot for species collapses. Using multiple data sources, I found strong evidence for major, sustained, population collapses of two urchins, one large predatory gastropod and a reef-building gastropod. Furthermore, of 59 molluscan species once-described in the taxonomic literature as common on Levant reefs, 38 were not found in the present-day surveys, and there was a total domination of non-indigenous species in molluscan assemblages. Temperature trends indicate an exceptional warming of the coastal waters in the past three decades. Though speculative at this stage, the fast rise in SST may have helped pushing these invertebrates beyond their physiological tolerance limits leading to population collapses and possible extirpations. If so, these collapses may indicate the initiation of a multi-species range contraction at the Mediterranean southeastern edge that may spread westward with additional warming. PMID:27853237

Mobile detection system to evaluate reactive hyperemia using radionuclide plethysmography.

PubMed

Harel, François; Ngo, Quam; Finnerty, Vincent; Hernandez, Edgar; Khairy, Paul; Dupuis, Jocelyn

2007-08-01

We validated a novel mobile detection system to evaluate reactive hyperemia using the radionuclide plethysmography technique. Twenty-six subjects underwent simultaneously radionuclide plethysmography with strain gauge plethysmography. Strain gauge and radionuclide methods showed excellent reproducibility with intraclass correlation coefficients of 0.96 and 0.89 respectively. There was also a good correlation of flows between the two methods during reactive hyperemia (r = 0.87). We conclude that radionuclide plethysmography using this mobile detection system is a non-invasive alternative to assess forearm blood flow and its dynamic variations during reactive hyperemia.

Mass spectrometry of long-lived radionuclides

NASA Astrophysics Data System (ADS)

Becker, Johanna Sabine

2003-10-01

The capability of determining element concentrations at the trace and ultratrace level and isotope ratios is a main feature of inorganic mass spectrometry. The precise and accurate determination of isotope ratios of long-lived natural and artificial radionuclides is required, e.g. for their environmental monitoring and health control, for studying radionuclide migration, for age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, for quality assurance and determination of the burn-up of fuel material in a nuclear power plant, for reprocessing plants, nuclear material accounting and radioactive waste control. Inorganic mass spectrometry, especially inductively coupled plasma mass spectrometry (ICP-MS) as the most important inorganic mass spectrometric technique today, possesses excellent sensitivity, precision and good accuracy for isotope ratio measurements and practically no restriction with respect to the ionization potential of the element investigated—therefore, thermal ionization mass spectrometry (TIMS), which has been used as the dominant analytical technique for precise isotope ratio measurements of long-lived radionuclides for many decades, is being replaced increasingly by ICP-MS. In the last few years instrumental progress in improving figures of merit for the determination of isotope ratio measurements of long-lived radionuclides in ICP-MS has been achieved by the application of a multiple ion collector device (MC-ICP-MS) and the introduction of the collision cell interface in order to dissociate disturbing argon-based molecular ions, to reduce the kinetic energy of ions and neutralize the disturbing noble gas ions (e.g. of 129Xe + for the determination of 129I). The review describes the state of the art and the progress of different inorganic mass spectrometric techniques such as ICP-MS, laser ablation ICP-MS vs. TIMS, glow discharge mass spectrometry, secondary ion mass spectrometry, resonance ionization mass

G-warm inflation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herrera, Ramón, E-mail: ramon.herrera@pucv.cl

A warm inflationary universe in the context of Galileon model or G-model is studied. Under a general formalism we study the inflationary dynamics and the cosmological perturbations considering a coupling of the form G (φ, X )= g (φ) X . As a concrete example, we consider an exponential potential together with the cases in which the dissipation and Galilean coefficients are constants. Also, we study the weak regime given by the condition R <1+3 gH φ-dot , and the strong regime in which 1< R +3 gH φ-dot . Additionally, we obtain constraints on the parameters during the evolutionmore » of G-warm inflation, assuming the condition for warm inflation in which the temperature T > H , the conditions or the weak and strong regimes, together with the consistency relation r = r ( n {sub s} ) from Planck data.« less

Immuno-SPET/CT and immuno-PET/CT: a step ahead to translational imaging.

PubMed

Pecking, Alain P; Bellet, Dominique; Alberini, Jean Louis

2012-10-01

Malignant tumours have the remarkable property to express cell surface antigens. Pressman was first reporting that radiolabeled antibodies were capable of organ localization. It was a promising challenge but the expected success and the development of this imaging method was limited by a poor imaging resolution despite a rather good specificity of the antibodies used. Identification of key cell surface markers is opening a new era as potential molecular imaging biomarkers in oncologic applications. Antibodies production has been promoted by the development of engineered fragments with preserved immunological properties and pharmacokinetics optimized for molecular imaging. A good compromise has to be obtained between the biological properties of the antibody and the physical half-life of the radionuclide. Several positron emission tomography (PET) radionuclides such as iodine-124, copper-64, yttrium-86 or zirconium-89 have been the focus of recent immuno-PET studies with interesting informative images in preclinical and clinical studies. Thanks to the development of more sensitive new detectors and specific software, molecular imaging methods, particularly PET imaging, allow nowadays the detection of lesions smaller than 5 mm in human. Immuno-PET can potentially be used for tumour detection and identification at diagnosis, staging and restaging, for treatment selection and monitoring, and during follow-up. Moreover the availability of matched imaging or therapeutic radionuclide pairs, such as (124)I/(131)I, (64)Cu/(67)Cu and (86)Y/(90)Y, make easier the quantification of tissue uptake and dosimetry calculation for radioimmunotherapy.

Developments in Bioremediation of Soils and Sediments Pollutedwith Metals and Radionuclides: 2. Field Research on Bioremediation of Metals and Radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hazen, Terry C.; Tabak, Henry H.

2007-03-15

Bioremediation of metals and radionuclides has had manyfield tests, demonstrations, and full-scale implementations in recentyears. Field research in this area has occurred for many different metalsand radionuclides using a wide array of strategies. These strategies canbe generally characterized in six major categories: biotransformation,bioaccumulation/bisorption, biodegradation of chelators, volatilization,treatment trains, and natural attenuation. For all field applicationsthere are a number of critical biogeochemical issues that most beaddressed for the successful field application. Monitoring andcharacterization parameters that are enabling to bioremediation of metalsand radionuclides are presented here. For each of the strategies a casestudy is presented to demonstrate a field application that usesmore » thisstrategy.« less

21 CFR 892.5650 - Manual radionuclide applicator system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... system. (a) Identification. A manual radionuclide applicator system is a manually operated device... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Manual radionuclide applicator system. 892.5650... planning computer programs, and accessories. (b) Classification. Class I (general controls). The device is...

21 CFR 892.5650 - Manual radionuclide applicator system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... system. (a) Identification. A manual radionuclide applicator system is a manually operated device... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Manual radionuclide applicator system. 892.5650... planning computer programs, and accessories. (b) Classification. Class I (general controls). The device is...

21 CFR 892.5650 - Manual radionuclide applicator system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... system. (a) Identification. A manual radionuclide applicator system is a manually operated device... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Manual radionuclide applicator system. 892.5650... planning computer programs, and accessories. (b) Classification. Class I (general controls). The device is...

21 CFR 892.5650 - Manual radionuclide applicator system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... system. (a) Identification. A manual radionuclide applicator system is a manually operated device... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Manual radionuclide applicator system. 892.5650... planning computer programs, and accessories. (b) Classification. Class I (general controls). The device is...

21 CFR 892.5650 - Manual radionuclide applicator system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... system. (a) Identification. A manual radionuclide applicator system is a manually operated device... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Manual radionuclide applicator system. 892.5650... planning computer programs, and accessories. (b) Classification. Class I (general controls). The device is...

The production of radionuclides for nuclear medicine from a compact, low-energy accelerator system.

PubMed

Webster, William D; Parks, Geoffrey T; Titov, Dmitry; Beasley, Paul

2014-05-01

The field of nuclear medicine is reliant on radionuclides for medical imaging procedures and radioimmunotherapy (RIT). The recent shut-downs of key radionuclide producers have highlighted the fragility of the current radionuclide supply network, however. To ensure that nuclear medicine can continue to grow, adding new diagnostic and therapy options to healthcare, novel and reliable production methods are required. Siemens are developing a low-energy, high-current - up to 10 MeV and 1 mA respectively - accelerator. The capability of this low-cost, compact system for radionuclide production, for use in nuclear medicine procedures, has been considered. The production of three medically important radionuclides - (89)Zr, (64)Cu, and (103)Pd - has been considered, via the (89)Y(p,n), (64)Ni(p,n) and (103)Rh(p,n) reactions, respectively. Theoretical cross-sections were generated using TALYS and compared to experimental data available from EXFOR. Stopping power values generated by SRIM have been used, with the TALYS-generated excitation functions, to calculate potential yields and isotopic purity in different irradiation regimes. The TALYS excitation functions were found to have a good agreement with the experimental data available from the EXFOR database. It was found that both (89)Zr and (64)Cu could be produced with high isotopic purity (over 99%), with activity yields suitable for medical diagnostics and therapy, at a proton energy of 10MeV. At 10MeV, the irradiation of (103)Rh produced appreciable quantities of (102)Pd, reducing the isotopic purity. A reduction in beam energy to 9.5MeV increased the radioisotopic purity to 99% with only a small reduction in activity yield. This work demonstrates that the low-energy, compact accelerator system under development by Siemens would be capable of providing sufficient quantities of (89)Zr, (64)Cu, and (103)Pd for use in medical diagnostics and therapy. It is suggested that the system could be used to produce many other

Recently amplified arctic warming has contributed to a continual global warming trend

NASA Astrophysics Data System (ADS)

Huang, Jianbin; Zhang, Xiangdong; Zhang, Qiyi; Lin, Yanluan; Hao, Mingju; Luo, Yong; Zhao, Zongci; Yao, Yao; Chen, Xin; Wang, Lei; Nie, Suping; Yin, Yizhou; Xu, Ying; Zhang, Jiansong

2017-12-01

The existence and magnitude of the recently suggested global warming hiatus, or slowdown, have been strongly debated1-3. Although various physical processes4-8 have been examined to elucidate this phenomenon, the accuracy and completeness of observational data that comprise global average surface air temperature (SAT) datasets is a concern9,10. In particular, these datasets lack either complete geographic coverage or in situ observations over the Arctic, owing to the sparse observational network in this area9. As a consequence, the contribution of Arctic warming to global SAT changes may have been underestimated, leading to an uncertainty in the hiatus debate. Here, we constructed a new Arctic SAT dataset using the most recently updated global SATs2 and a drifting buoys based Arctic SAT dataset11 through employing the `data interpolating empirical orthogonal functions' method12. Our estimate of global SAT rate of increase is around 0.112 °C per decade, instead of 0.05 °C per decade from IPCC AR51, for 1998-2012. Analysis of this dataset shows that the amplified Arctic warming over the past decade has significantly contributed to a continual global warming trend, rather than a hiatus or slowdown.

Fukushima Daiichi Radionuclide Inventories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cardoni, Jeffrey N.; Jankovsky, Zachary Kyle

Radionuclide inventories are generated to permit detailed analyses of the Fukushima Daiichi meltdowns. This is necessary information for severe accident calculations, dose calculations, and source term and consequence analyses. Inventories are calculated using SCALE6 and compared to values predicted by international researchers supporting the OECD/NEA's Benchmark Study on the Accident at Fukushima Daiichi Nuclear Power Station (BSAF). Both sets of inventory information are acceptable for best-estimate analyses of the Fukushima reactors. Consistent nuclear information for severe accident codes, including radionuclide class masses and core decay powers, are also derived from the SCALE6 analyses. Key nuclide activity ratios are calculated asmore » functions of burnup and nuclear data in order to explore the utility for nuclear forensics and support future decommissioning efforts.« less

The Great Warming Brian Fagan

NASA Astrophysics Data System (ADS)

Fagan, B. M.

2010-12-01

The Great Warming is a journey back to the world of a thousand years ago, to the Medieval Warm Period. Five centuries of irregular warming from 800 to 1250 had beneficial effects in Europe and the North Atlantic, but brought prolonged droughts to much of the Americas and lands affected by the South Asian monsoon. The book describes these impacts of warming on medieval European societies, as well as the Norse and the Inuit of the far north, then analyzes the impact of harsh, lengthy droughts on hunting societies in western North America and the Ancestral Pueblo farmers of Chaco Canyon, New Mexico. These peoples reacted to drought by relocating entire communities. The Maya civilization was much more vulnerable that small-scale hunter-gatherer societies and subsistence farmers in North America. Maya rulers created huge water storage facilities, but their civilization partially collapsed under the stress of repeated multiyear droughts, while the Chimu lords of coastal Peru adapted with sophisticated irrigation works. The climatic villain was prolonged, cool La Niñalike conditions in the Pacific, which caused droughts from Venezuela to East Asia, and as far west as East Africa. The Great Warming argues that the warm centuries brought savage drought to much of humanity, from China to Peru. It also argues that drought is one of the most dangerous elements in today’s humanly created global warming, often ignored by preoccupied commentators, but with the potential to cause over a billion people to starve. Finally, I use the book to discuss the issues and problems of communicating multidisciplinary science to the general public.

Climatic warming destabilizes forest ant communities

PubMed Central

Diamond, Sarah E.; Nichols, Lauren M.; Pelini, Shannon L.; Penick, Clint A.; Barber, Grace W.; Cahan, Sara Helms; Dunn, Robert R.; Ellison, Aaron M.; Sanders, Nathan J.; Gotelli, Nicholas J.

2016-01-01

How will ecological communities change in response to climate warming? Direct effects of temperature and indirect cascading effects of species interactions are already altering the structure of local communities, but the dynamics of community change are still poorly understood. We explore the cumulative effects of warming on the dynamics and turnover of forest ant communities that were warmed as part of a 5-year climate manipulation experiment at two sites in eastern North America. At the community level, warming consistently increased occupancy of nests and decreased extinction and nest abandonment. This consistency was largely driven by strong responses of a subset of thermophilic species at each site. As colonies of thermophilic species persisted in nests for longer periods of time under warmer temperatures, turnover was diminished, and species interactions were likely altered. We found that dynamical (Lyapunov) community stability decreased with warming both within and between sites. These results refute null expectations of simple temperature-driven increases in the activity and movement of thermophilic ectotherms. The reduction in stability under warming contrasts with the findings of previous studies that suggest resilience of species interactions to experimental and natural warming. In the face of warmer, no-analog climates, communities of the future may become increasingly fragile and unstable. PMID:27819044

Climatic warming destabilizes forest ant communities.

PubMed

Diamond, Sarah E; Nichols, Lauren M; Pelini, Shannon L; Penick, Clint A; Barber, Grace W; Cahan, Sara Helms; Dunn, Robert R; Ellison, Aaron M; Sanders, Nathan J; Gotelli, Nicholas J

2016-10-01

How will ecological communities change in response to climate warming? Direct effects of temperature and indirect cascading effects of species interactions are already altering the structure of local communities, but the dynamics of community change are still poorly understood. We explore the cumulative effects of warming on the dynamics and turnover of forest ant communities that were warmed as part of a 5-year climate manipulation experiment at two sites in eastern North America. At the community level, warming consistently increased occupancy of nests and decreased extinction and nest abandonment. This consistency was largely driven by strong responses of a subset of thermophilic species at each site. As colonies of thermophilic species persisted in nests for longer periods of time under warmer temperatures, turnover was diminished, and species interactions were likely altered. We found that dynamical (Lyapunov) community stability decreased with warming both within and between sites. These results refute null expectations of simple temperature-driven increases in the activity and movement of thermophilic ectotherms. The reduction in stability under warming contrasts with the findings of previous studies that suggest resilience of species interactions to experimental and natural warming. In the face of warmer, no-analog climates, communities of the future may become increasingly fragile and unstable.

Radionuclide-binding compound, a radionuclide delivery system, a method of making a radium complexing compound, a method of extracting a radionuclide, and a method of delivering a radionuclide

DOEpatents

Fisher, Darrell R.; Wai, Chien M.; Chen, Xiaoyuan

2000-01-01

The invention pertains to compounds which specifically bind radionuclides, and to methods of making radionuclide complexing compounds. In one aspect, the invention includes a radionuclide delivery system comprising: a) a calix[n]arene-crown-[m]-ether compound, wherein n is an integer greater than 3, and wherein m is an integer greater than 3, the calix[n]arene-crown-[m]-ether compound comprising at least two ionizable groups; and b) an antibody attached to the calix[n]arene-crown-[m]-ether compound. In another aspect, the invention includes a method of making a radium complexing compound, comprising: a) providing a calix[n]arene compound, wherein n is an integer greater than 3, the calix[n]arene compound comprising n phenolic hydroxyl groups; b) providing a crown ether precursor, the crown ether precursor comprising a pair of tosylated ends; c) reacting the pair of tosylated ends with a pair of the phenolic hydroxyl groups to convert said pair of phenolic hydroxyl groups to ether linkages, the ether linkages connecting the crown ether precursor to the calix[n]arene to form a calix[n]arene-crown-[m]-ether compound, wherein m is an integer greater than 3; d) converting remaining phenolic hydroxyl groups to esters; e) converting the esters to acids, the acids being proximate a crown-[m]-ether portion of the calix[n]arene-crown-[m]-ether compound; and f) providing a Ra.sup.2+ ion within the crown-[m]-ether portion of the calix[n]arene-crown-[m]-ether compound.

Urban warming reduces aboveground carbon storage.

PubMed

Meineke, Emily; Youngsteadt, Elsa; Dunn, Robert R; Frank, Steven D

2016-10-12

A substantial amount of global carbon is stored in mature trees. However, no experiments to date test how warming affects mature tree carbon storage. Using a unique, citywide, factorial experiment, we investigated how warming and insect herbivory affected physiological function and carbon sequestration (carbon stored per year) of mature trees. Urban warming increased herbivorous arthropod abundance on trees, but these herbivores had negligible effects on tree carbon sequestration. Instead, urban warming was associated with an estimated 12% loss of carbon sequestration, in part because photosynthesis was reduced at hotter sites. Ecosystem service assessments that do not consider urban conditions may overestimate urban tree carbon storage. Because urban and global warming are becoming more intense, our results suggest that urban trees will sequester even less carbon in the future. © 2016 The Author(s).

How Do Radionuclides Accumulate in Marine Organisms? A Case Study of Europium with Aplysina cavernicola

DOE PAGES

Maloubier, Melody; Shuh, David K.; Minasian, Stefan G.; ...

2016-09-15

In the ocean, complex interactions between natural and anthropogenic radionuclides, seawater, and diverse marine biota provide a unique window through which to examine ecosystem and trophic transfer mechanisms in cases of accidental dissemination. The nature of interaction between radionuclides, the marine environment, and marine species is therefore essential for better understanding transfer mechanisms from the hydrosphere to the biosphere. Although data pertaining to the rate of global transfer are often available, little is known regarding the mechanism of environmental transport and uptake of heavy radionuclides by marine species. Among marine species, sponges are immobile active filter feeders and have beenmore » identified as hyperaccumulators of several heavy metals. We have selected the Mediterranean sponge Aplysina cavernicola as a model species for this study. Actinide elements are not the only source of radioactive release in cases of civilian nuclear events; however, their physicochemical transfer mechanisms to marine species remain largely unknown. We have targeted europium(III) as a representative of the trivalent actinides such as americium or curium. To unravel biological uptake mechanisms of europium in A. cavernicola, we have combined radiometric (γ) measurements with spectroscopic (time-resolved laser-induced fluorescence spectroscopy, TRLIFS, and X-ray absorption near-edge structure, XANES) and imaging (transmission electron microscopy, TEM, and scanning transmission X-ray microscopy, STXM) techniques. Here, we have observed that the colloids of NaEu(CO 3) 2 ·nH 2O formed in seawater are taken up by A. cavernicola with no evidence that lethal dose has been reached in our working conditions. Spectroscopic results suggest that there is no change of speciation during uptake. Finally, TEM and STXM images recorded at different locations across a sponge cross section, together with differential cell separation, indicate the presence of europium

How Do Radionuclides Accumulate in Marine Organisms? A Case Study of Europium with Aplysina cavernicola

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maloubier, Melody; Shuh, David K.; Minasian, Stefan G.

In the ocean, complex interactions between natural and anthropogenic radionuclides, seawater, and diverse marine biota provide a unique window through which to examine ecosystem and trophic transfer mechanisms in cases of accidental dissemination. The nature of interaction between radionuclides, the marine environment, and marine species is therefore essential for better understanding transfer mechanisms from the hydrosphere to the biosphere. Although data pertaining to the rate of global transfer are often available, little is known regarding the mechanism of environmental transport and uptake of heavy radionuclides by marine species. Among marine species, sponges are immobile active filter feeders and have beenmore » identified as hyperaccumulators of several heavy metals. We have selected the Mediterranean sponge Aplysina cavernicola as a model species for this study. Actinide elements are not the only source of radioactive release in cases of civilian nuclear events; however, their physicochemical transfer mechanisms to marine species remain largely unknown. We have targeted europium(III) as a representative of the trivalent actinides such as americium or curium. To unravel biological uptake mechanisms of europium in A. cavernicola, we have combined radiometric (γ) measurements with spectroscopic (time-resolved laser-induced fluorescence spectroscopy, TRLIFS, and X-ray absorption near-edge structure, XANES) and imaging (transmission electron microscopy, TEM, and scanning transmission X-ray microscopy, STXM) techniques. Here, we have observed that the colloids of NaEu(CO 3) 2 ·nH 2O formed in seawater are taken up by A. cavernicola with no evidence that lethal dose has been reached in our working conditions. Spectroscopic results suggest that there is no change of speciation during uptake. Finally, TEM and STXM images recorded at different locations across a sponge cross section, together with differential cell separation, indicate the presence of europium

Livermore Accelerator Source for Radionuclide Science (LASRS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Scott; Bleuel, Darren; Johnson, Micah

The Livermore Accelerator Source for Radionuclide Science (LASRS) will generate intense photon and neutron beams to address important gaps in the study of radionuclide science that directly impact Stockpile Stewardship, Nuclear Forensics, and Nuclear Material Detection. The co-location of MeV-scale neutral and photon sources with radiochemical analytics provides a unique facility to meet current and future challenges in nuclear security and nuclear science.

Radionuclide-anesthetic flow study: a new technique for the study of regional anesthesia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bauman, J.M.; Middaugh, R.E.; Cawthon, M.A.

1986-09-01

A new technique to study the dynamics of in vivo distribution of regional anesthetics is described. Five hundred microcuries of technetium-99m diethylenetriaminepentaacetic acid (DTPA) added to the anesthetic in a syringe prior to injection allows both dynamic and static imaging to assess the initial distribution of the injected anesthetic. Superimposed bone scans or transmission scans help delineate anatomy. The radionuclide-anesthetic flow study is a simple, safe technique to investigate both the spread of regional anesthetics and the factors that affect it.

21 CFR 892.1420 - Radionuclide test pattern phantom.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide test pattern phantom. 892.1420 Section 892.1420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1420 Radionuclide test pattern phantom...

Global warming 2007. An update to global warming: the balance of evidence and its policy implications.

PubMed

Keller, Charles F

2007-03-09

In the four years since my original review (Keller[25]; hereafter referred to as CFK03), research has clarified and strengthened our understanding of how humans are warming the planet. So many of the details highlighted in the IPCC's Third Assessment Report[21] and in CFK03 have been resolved that I expect many to be a bit overwhelmed, and I hope that, by treating just the most significant aspects of the research, this update may provide a road map through the expected maze of new information. In particular, while most of CFK03 remains current, there are important items that have changed: Most notable is the resolution of the conundrum that mid-tropospheric warming did not seem to match surface warming. Both satellite and radiosonde (balloon-borne sensors) data reduction showed little warming in the middle troposphere (4-8 km altitude). In the CFK03 I discussed potential solutions to this problem, but at that time there was no clear resolution. This problem has now been solved, and the middle troposphere is seen to be warming apace with the surface. There have also been advances in determinations of temperatures over the past 1,000 years showing a cooler Little Ice Age (LIA) but essentially the same warming during medieval times (not as large as recent warming). The recent uproar over the so-called "hockey stick" temperature determination is much overblown since at least seven other groups have made relatively independent determinations of northern hemisphere temperatures over the same time period and derived essentially the same results. They differ on how cold the LIA was but essentially agree with the Mann's hockey stick result that the Medieval Warm Period was not as warm as the last 25 years. The question of the sun's influence on climate continues to generate controversy. It appears there is a growing consensus that, while the sun was a major factor in earlier temperature variations, it is incapable of having caused observed warming in the past quarter

The Tropical Western Hemisphere Warm Pool

NASA Astrophysics Data System (ADS)

Wang, C.; Enfield, D. B.

2002-12-01

The paper describes and examines variability of the tropical Western Hemisphere warm pool (WHWP) of water warmer than 28.5oC. The WHWP is the second-largest tropical warm pool on Earth. Unlike the Eastern Hemisphere warm pool in the western Pacific, which straddles the equator, the WHWP is entirely north of the equator. At various stages of development the WHWP extends over parts of the eastern North Pacific, the Gulf of Mexico, the Caribbean, and the western tropical North Atlantic. It has a large seasonal cycle and its interannual fluctuations of area and intensity are significant. Surface heat fluxes warm the WHWP through the boreal spring to an annual maximum of SST and WHWP area in the late summer/early fall, associated with eastern North Pacific and Atlantic hurricane activities and rainfall from northern South America to the southern tier of the United States. Observations suggest that a positive ocean-atmosphere feedback operating through longwave radiation and associated cloudiness seems to operate in the WHWP. During winter preceding large warm pool, there is an alteration of the Walker and Hadley circulation cells that serves as a "tropospheric bridge" for transferring Pacific ENSO effects to the Atlantic sector and inducing initial warming of warm pool. Associated with the warm SST anomalies is a decrease in sea level pressure anomalies and an anomalous increase in atmospheric convection and cloudiness. The increase in convective activity and cloudiness results in less net longwave radiation loss from the sea surface, which then reinforces SST anomalies.

Production of novel diagnostic radionuclides in small medical cyclotrons.

PubMed

Synowiecki, Mateusz Adam; Perk, Lars Rutger; Nijsen, J Frank W

2018-01-01

The global network of cyclotrons has expanded rapidly over the last decade. The bulk of its industrial potential is composed of small medical cyclotrons with a proton energy below 20 MeV for radionuclides production. This review focuses on the recent developments of novel medical radionuclides produced by cyclotrons in the energy range of 3 MeV to 20 MeV. The production of the following medical radionuclides will be described based on available literature sources: Tc-99 m, I-123, I-124, Zr-89, Cu-64, Ga-67, Ga-68, In-111, Y-86 and Sc-44. Remarkable developments in the production process have been observed in only some cases. More research is needed to make novel radionuclide cyclotron production available for the medical industry.

Decadal evolution of the surface energy budget during the fast warming and global warming hiatus periods in the ERA-interim

NASA Astrophysics Data System (ADS)

Hu, Xiaoming; Sejas, Sergio A.; Cai, Ming; Taylor, Patrick C.; Deng, Yi; Yang, Song

2018-05-01

The global-mean surface temperature has experienced a rapid warming from the 1980s to early-2000s but a muted warming since, referred to as the global warming hiatus in the literature. Decadal changes in deep ocean heat uptake are thought to primarily account for the rapid warming and subsequent slowdown. Here, we examine the role of ocean heat uptake in establishing the fast warming and warming hiatus periods in the ERA-Interim through a decomposition of the global-mean surface energy budget. We find the increase of carbon dioxide alone yields a nearly steady increase of the downward longwave radiation at the surface from the 1980s to the present, but neither accounts for the fast warming nor warming hiatus periods. During the global warming hiatus period, the transfer of latent heat energy from the ocean to atmosphere increases and the total downward radiative energy flux to the surface decreases due to a reduction of solar absorption caused primarily by an increase of clouds. The reduction of radiative energy into the ocean and the surface latent heat flux increase cause the ocean heat uptake to decrease and thus contribute to the slowdown of the global-mean surface warming. Our analysis also finds that in addition to a reduction of deep ocean heat uptake, the fast warming period is also driven by enhanced solar absorption due predominantly to a decrease of clouds and by enhanced longwave absorption mainly attributed to the air temperature feedback.

Nature of the Warm Excess in eps Eri: Asteroid belt or Dragged-in Grains

NASA Astrophysics Data System (ADS)

Su, Kate

2014-10-01

Eps Eri and its debris disk provide a unique opportunity to probe the outer zones of a planetary system, due to its young age (~1 Gyr) and proximity (3.22 pc, the closest prominent debris disk by more than a factor of two). It is the Rosetta Stone for more distant exoplanetary debris systems and thus critical to understanding the mid-term evolution of our Solar System. From resolved images in the far-infrared and submillimeter along with spectra from 10-35 and 55-95 microns, Backman et al. (2009) found that the eps Eri disk has a complex structure, with multiple zones in both warm (asteroid-like) and cold (KBO-like) components. However, Reidemeister et al. (2011), on the contrary, suggested that the system has only one dominant cold belt and the warm excess originates from small grains in the cold disk, which are transported inward by the combination of P-R and stellar wind drags. Although both models fit the disk SED and marginally resolved far-infrared images relatively well, the resultant disk structures in the 15-50 AU range at mid-infrared wavelengths are expected to be very different. We, therefore, propose to obtain a 35 micron image of the eps Eri system using the FORCAST on SOFIA to test the validity of any models for this zone in eps Eri. No other available facilities can obtain such a 35 micron image, which will provide general constraints on the nature of the warm excess and any potential shepherding planets and their orbits in this iconic debris system. This is a re-submission of our approved cycle 2 program (02_0061), which was scheduled to be executed in Oct 2014. Due to the delay and the uncertain length of the SOFIA aircraft maintenance, it is not clear at the time of the cycle 3 deadline whether the approved observations will be executed in cycle 2. If the observations are carried out in cycle 2, we would withdraw the proposal in cycle 3.

Experimental winter warming modifies thermal performance and primes acorn ants for warm weather.

PubMed

MacLean, Heidi J; Penick, Clint A; Dunn, Robert R; Diamond, Sarah E

2017-07-01

The frequency of warm winter days is increasing under global climate change, but how organisms respond to warmer winters is not well understood. Most studies focus on growing season responses to warming. Locomotor performance is often highly sensitive to temperature, and can determine fitness outcomes through a variety of mechanisms including resource acquisition and predator escape. As a consequence, locomotor performance, and its impacts on fitness, may be strongly affected by winter warming in winter-active species. Here we use the acorn ant, Temnothorax curvispinosus, to explore how thermal performance (temperature-driven plasticity) in running speed is influenced by experimental winter warming of 3-5°C above ambient in a field setting. We used running speed as a measure of performance as it is a common locomotor trait that influences acquisition of nest sites and food in acorn ants. Experimental winter warming significantly altered thermal performance for running speed at high (26 and 36°C) but not low test temperatures (6 and 16°C). Although we saw little differentiation in thermal performance at cooler test temperatures, we saw a marked increase in running speed at the hotter test temperatures for ants that experienced warmer winters compared with those that experienced cooler winters. Our results provide evidence that overwintering temperatures can substantially influence organismal performance, and suggest that we cannot ignore overwintering effects when forecasting organismal responses to environmental changes in temperature. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sustained acceleration of soil carbon decomposition observed in a 6-year warming experiment in a warm-temperate forest in southern Japan.

PubMed

Teramoto, Munemasa; Liang, Naishen; Takagi, Masahiro; Zeng, Jiye; Grace, John

2016-10-17

To examine global warming's effect on soil organic carbon (SOC) decomposition in Asian monsoon forests, we conducted a soil warming experiment with a multichannel automated chamber system in a 55-year-old warm-temperate evergreen broadleaved forest in southern Japan. We established three treatments: control chambers for total soil respiration, trenched chambers for heterotrophic respiration (R h ), and warmed trenched chambers to examine warming effect on R h . The soil was warmed with an infrared heater above each chamber to increase soil temperature at 5 cm depth by about 2.5 °C. The warming treatment lasted from January 2009 to the end of 2014. The annual warming effect on R h (an increase per °C) ranged from 7.1 to17.8% °C -1 . Although the warming effect varied among the years, it averaged 9.4% °C -1 over 6 years, which was close to the value of 10.1 to 10.9% °C -1 that we calculated using the annual temperature-efflux response model of Lloyd and Taylor. The interannual warming effect was positively related to the total precipitation in the summer period, indicating that summer precipitation and the resulting soil moisture level also strongly influenced the soil warming effect in this forest.

Exposure to radionuclides in smoke from vegetation fires.

PubMed

Carvalho, Fernando P; Oliveira, João M; Malta, Margarida

2014-02-15

Naturally occurring radionuclides of uranium, thorium, radium, lead and polonium were determined in bushes and trees and in the smoke from summer forest fires. Activity concentrations of radionuclides in smoke particles were much enriched when compared to original vegetation. Polonium-210 ((210)Po) in smoke was measured in concentrations much higher than all other radionuclides, reaching 7,255 ± 285 Bq kg(-1), mostly associated with the smaller size smoke particles (<1.0 μm). Depending on smoke particle concentration, (210)Po in surface air near forest fires displayed volume concentrations up to 70 m Bq m(-3), while in smoke-free air (210)Po concentration was about 30 μ Bq m(-3). The estimated absorbed radiation dose to an adult member of the public or a firefighter exposed for 24h to inhalation of smoke near forest fires could exceed 5 μSv per day, i.e, more than 2000 times above the radiation dose from background radioactivity in surface air, and also higher than the radiation dose from (210)Po inhalation in a chronic cigarette smoker. It is concluded that prolonged exposure to smoke allows for enhanced inhalation of radionuclides associated with smoke particles. Due to high radiotoxicity of alpha emitting radionuclides, and in particular of (210)Po, the protection of respiratory tract of fire fighters is strongly recommended. Copyright © 2013 Elsevier B.V. All rights reserved.

Metal-isonitrile adducts for preparing radionuclide complexes for labelling and imaging agents

DOEpatents

Jones, Alun G.; Davison, Alan; Abrams, Michael J.

1987-01-01

A method for preparing a coordination complex of an isonitrile ligand and radionuclide such as Tc, Ru, Co, Pt, Fe, Os, Ir, W, Re, Cr, Mo, Mn, Ni, Rh, Pd, Nb and Ta is disclosed. The method comprises preparing a soluble metal adduct of said isonitrile ligand by admixing said ligand with a salt of a displaceable metal having a complete d-electron shell selected from the group consisting of Zn, Ga, Cd, In, Sn, Hg, Tl, Pb and Bi to form a soluble metal-isonitrile salt, and admixing said metal isonitrile salt with a salt comprising said radioactive metal in a suitable solvent to displace said displaceable metal with the radioactive metal thereby forming said coordination. The complex is useful as a diagnostic agent for labelling liposomes or vesicles, and selected living cells containing lipid membranes, such as blood clots, myocardial tissue, gall bladder tissue, etc.

Radionuclides in nephrology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lausanne, A.B.D.

In 47 expert contributions, this volume provides a summary of the latest research on radionuclides in nephro-urology together with current and new clinical applications especially in renovascular hypertension, kidney transplantation, and metabolic and urological diseases. In addition, attention is given to aspects of basic renal physiology and function and possible applications of nuclear magnetic resonance and spectroscopy in nephro-urology. New testing procedures which promise to improve diagnosis, and new radiopharmaceuticals are described. The reports are divided into eight sections, the first of which features studies on the renin-angiotensin system, cisplatin, atrial natriuretic factor and determining plasma oxalate. Four papers describemore » a number of new radiopharmaceuticals which have the potential to replace hippuran. In the third section, radionuclide methods for the measurement of renal function parameters are discussed. The book then focuses on the potential role of captopril in the improved diagnosis of renovascular hypertension. Applications of nuclear magnetic resonance and spectroscopy are demonstrated in the diagnosis of acute pyelonephritis, kidney assessment after lithotripsy, kidney evaluation prior to transplantation, and in monitoring renal ischemia during hypotension.« less

Warm-up: A Psychophysiological Phenomenon.

ERIC Educational Resources Information Center

Lopez, Richard; Dausman, Cindy

1981-01-01

The effectiveness of warm-up as an aid to athletic performance is related to an interaction of both psychological and physiological factors. Benefits of warm-up include an increase in blood and muscle temperatures and an increased muscular endurance. (JN)

Respiratory muscle specific warm-up and elite swimming performance.

PubMed

Wilson, Emma E; McKeever, Tricia M; Lobb, Claire; Sherriff, Tom; Gupta, Luke; Hearson, Glenn; Martin, Neil; Lindley, Martin R; Shaw, Dominick E

2014-05-01

Inspiratory muscle training has been shown to improve performance in elite swimmers, when used as part of routine training, but its use as a respiratory warm-up has yet to be investigated. To determine the influence of inspiratory muscle exercise (IME) as a respiratory muscle warm-up in a randomised controlled cross-over trial. A total of 15 elite swimmers were assigned to four different warm-up protocols and the effects of IME on 100 m freestyle swimming times were assessed.Each swimmer completed four different IME warm-up protocols across four separate study visits: swimming-only warm-up; swimming warm-up plus IME warm-up (2 sets of 30 breaths with a 40% maximum inspiratory mouth pressure load using the Powerbreathe inspiratory muscle trainer); swimming warm-up plus sham IME warm-up (2 sets of 30 breaths with a 15% maximum inspiratory mouth pressure load using the Powerbreathe inspiratory muscle trainer); and IME-only warm-up. Swimmers performed a series of physiological tests and scales of perception (rate of perceived exertion and dyspnoea) at three time points (pre warm-up, post warm-up and post time trial). The combined standard swimming warm-up and IME warm-up were the fastest of the four protocols with a 100 m time of 57.05 s. This was significantly faster than the IME-only warm-up (mean difference=1.18 s, 95% CI 0.44 to 1.92, p<0.01) and the swim-only warm-up (mean difference=0.62 s, 95% CI 0.001 to 1.23, p=0.05). Using IME combined with a standard swimming warm-up significantly improves 100 m freestyle swimming performance in elite swimmers.

Heat Exchnage in the Black Skipjack, and the Blood-Gas Relationship of Warm-Bodied Fishes

PubMed Central

Graham, Jeffrey B.

1973-01-01

The black skipjack, Euthynnus lineatus, uses a centrally located vascular heat exchanger to maintain core body temperatures warmer than ambient sea water. The heat exchanger is composed of the dorsal aorta, the posterior cardinal vein, and a large vertical rete. The dorsal aorta is embedded in the posterior cardinal vein and is completely bathed in venous blood. Skipjack hemoglobin appears similar to that of the bluefin tuna in that oxygen capacity is unaffected by changing temperature. Temperature-insensitive hemoglobin may function in warm-bodied fishes to prevent the premature dissociation of oxygen from hemoglobin as blood is warmed en route to the muscles. Images PMID:16592097

Distribution of radionuclides in Dardanelle Reservoir sediments.

PubMed

Forgy, J R; Epperson, C E; Swindle, D L

1984-02-01

Natural and reactor-discharged gamma-ray emitting radionuclides were measured in Dardanelle Reservoir surface sediments taken near the Arkansas Nuclear One Power Plant site. Samples represented several water depths and particle sizes, at 33 locations, in a field survey conducted in early September 1980. Radionuclide contents of dry sediments ranged as follows: natural radioactivity (40K as well as uranium and thorium decay products) 661-1210 Bq/kg; and reactor discharged radioactivity (137Cs, 134Cs, 60Co,, 58Co, 54Mn), no detectable activity to 237 Bq/kg. In general, radionuclide contents were positively correlated with decreasing sediment particle size. The average external whole-body and skin doses from all measurable reactor-discharged radionuclides were calculated according to the mathematical formula for determining external dose from sediment given by the U.S. Nuclear Regulatory Commission (NRC). Inside the discharge embayment near the reactor discharge canal, the doses were 1.7 X 10(-3) mSv/yr to the whole body and 2.0 X 10(-3) mSv/yr to the skin. Outside this area, the doses were 0.15 X 10(-3) and 0.18 X 10(-3) mSv/yr to the whole body and skin, respectively.

Frequency of Deep Convective Clouds and Global Warming

NASA Technical Reports Server (NTRS)

Aumann, Hartmut H.; Teixeira, Joao

2008-01-01

This slide presentation reviews the effect of global warming on the formation of Deep Convective Clouds (DCC). It concludes that nature responds to global warming with an increase in strong convective activity. The frequency of DCC increases with global warming at the rate of 6%/decade. The increased frequency of DCC with global warming alone increases precipitation by 1.7%/decade. It compares the state of the art climate models' response to global warming, and concludes that the parametrization of climate models need to be tuned to more closely emulate the way nature responds to global warming.

Gravitational waves from warm inflation

NASA Astrophysics Data System (ADS)

Li, Xi-Bin; Wang, He; Zhu, Jian-Yang

2018-03-01

A fundamental prediction of inflation is a nearly scale-invariant spectrum of gravitational wave. The features of such a signal provide extremely important information about the physics of the early universe. In this paper, we focus on several topics about warm inflation. First, we discuss the stability property about warm inflation based on nonequilibrium statistical mechanics, which gives more fundamental physical illustrations to thermal property of such model. Then, we calculate the power spectrum of gravitational waves generated during warm inflation, in which there are three components contributing to such spectrum: thermal term, quantum term, and cross term combining the both. We also discuss some interesting properties about these terms and illustrate them in different panels. As a model different from cold inflation, warm inflation model has its individual properties in observational practice, so we finally give a discussion about the observational effect to distinguish it from cold inflation.

Forced-Air Warming During Pediatric Surgery: A Randomized Comparison of a Compressible with a Noncompressible Warming System.

PubMed

Triffterer, Lydia; Marhofer, Peter; Sulyok, Irene; Keplinger, Maya; Mair, Stefan; Steinberger, Markus; Klug, Wolfgang; Kimberger, Oliver

2016-01-01

Perioperative hypothermia is a common problem, challenging the anesthesiologist and influencing patient outcome. Efficient and safe perioperative active warming is therefore paramount; yet, it can be particularly challenging in pediatric patients. Forced-air warming technology is the most widespread patient-warming option, with most forced-air warming systems consisting of a forced-air blower connected to a compressible, double layer plastic and/or a paper blanket with air holes on the patient side. We compared an alternative, forced-air, noncompressible, under-body patient-warming mattress (Baby/Kleinkinddecke of MoeckWarmingSystems, Moeck und Moeck GmbH; group MM) with a standard, compressible warming mattress system (Pediatric Underbody, Bair Hugger, 3M; group BH). The study included 80 patients aged <2 years, scheduled for elective surgery. After a preoperative core temperature measurement, the patients were placed on the randomized mattress in the operation theater and 4 temperature probes were applied rectally and to the patients' skin. The warming devices were turned on as soon as possible to the level for pediatric patients as recommended by the manufacturer (MM = 40°C, BH = 43°C). There was a distinct difference of temperature slope between the 2 groups: core temperatures of patients in the group MM remained stable and mean of the core temperature of patients in the group BH increased significantly (difference: +1.48°C/h; 95% confidence interval, 0.82-2.15°C/h; P = 0.0001). The need for temperature downregulation occurred more often in the BH group, with 22 vs 7 incidences (RR, 3.14; 95% confidence interval, 1.52-6.52; P = 0.0006). Skin temperatures were all lower in the MM group. Perioperatively, no side effects related to a warming device were observed in any group. Both devices are feasible choices for active pediatric patient warming, with the compressible mattress system being better suited to increase core temperature. The use of lower pediatric

Warm-season severe wind events in Germany

NASA Astrophysics Data System (ADS)

Gatzen, Christoph

2013-04-01

A 15-year data set of wind measurements was analyzed with regard to warm season severe wind gusts in Germany. For April to September of the years 1997 to 2011, 1035 wind measurements of 26 m/s or greater were found. These wind reports were associated with 268 wind events. In total, 252 convective wind events contributed to 837 (81%) of the wind reports, 16 non-convective synoptic-scale wind events contributed to 198 reports (19%). Severe wind events were found with synoptic situations characterized by rather strong mid-level flow and advancing mid-level troughs. Severe convective wind events were analyzed using radar images and classified with respect to the observed radar structure. The most important convective mode was squall lines that were associated with one third of all severe wind gusts, followed by groups, bow echo complexes, and bow echoes. Supercells and cells were not associated with many wind reports. The low contribution of isolated cells indicates that rather large-scale forcing by synoptic-scale features like fronts is important for German severe wind events. Bow echoes were found to be present for 58% of all wind reports. The movement speed of bow echoes indicated a large variation with a maximum speed of 33 m/s. Extreme wind events as well as events with more than 15 wind reports were found to be related to higher movement speeds. Concentrating on the most intense events, derechos seem to be very important to the warm season wind threat in Germany. Convective events with a path length of more than 400 km contributed to 36% of all warm-season wind gusts in this data set. Furthermore, eight of nine extreme gusts exceeding 40 m/s were recorded with derecho events.

Geomorphic control of radionuclide diffusion in desert soils

USGS Publications Warehouse

Pelletier, J.D.; Harrington, C.D.; Whitney, J.W.; Cline, M.; DeLong, S.B.; Keating, G.; Ebert, T.K.

2005-01-01

Diffusion is a standard model for the vertical migration of radionuclides in soil profiles. Here we show that diffusivity values inferred from fallout 137CS profiles in soils on the Fortymile Wash alluvial fan, Nye County, Nevada, have a strong inverse correlation with the age of the geomorphic surface. This result suggests that radionuclide-bound particles are predominantly transported by infiltration rather than by bulk-mixing processes such as wetting/ drying, freeze/thaw, and bioturbation. Our results provide a preliminary basis for using soil-geomorphic mapping, point-based calibration data, and the diffusion model to predict radionuclide trans desert soils within a pedotransfer-function approach. Copyright 2005 by the American Geophysical Union.

Radionuclide imaging of myocardial infarction using Tc-99m TBI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holman, B.L.; Campbell, S.; Kirshenbaum, J.M.

The cationic complex Tc-99m t-butylisonitrile (TBI) concentrates in the myocardial tissue of several animal species. Its myocardial distribution is proportional to blood flow both in zones of ischemia and in normal myocardium at rest. Planar, tomographic, and gated myocardial images have been obtained using Tc-99m TBI in the human. The authors investigated the potential application of Tc-99m TBI imaging to detect and localize myocardial infarction. Four subjects without clinical evidence of cardiovascular disease and five patients with ECG evidence of previous myocardial infarction were studied. Tc-99m TBI (10mCi) was injected intravenously with the patient in a resting state with planarmore » imaging in the anterior, 30 and 70 degree LAO projections beginning one hr after injection. The distribution of the tracer was homogeneous throughout the left ventricular wall in the normal subjects. Regional perfusion defects were present in 4/5 of the patients with myocardial infarction. Location of the defects corresponded to the location of the infarct using ECG criteria (2 inferoposterior and 2 anterior). The patient in whom the Tc-99m TBI image appeared normal had sustained a subendocardial myocardial infarct which could not be localized by ECG; the other 4 pts had transmural infarcts. Anterior and 30 degree LAO images were of excellent quality in all cases; there was overlap of the liver on the inferior wall of the left ventricle on the 70 degree LAO views. The authors conclude that accurate perfusion imaging may be possible using Tc-99m TBI in patients with transmural myocardial infarction.« less

Predator contributions to belowground responses to warming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maran, A. M.; Pelini, S. L.

Identifying the factors that control soil CO 2 emissions will improve our ability to predict the magnitude of climate change–soil ecosystem feedbacks. Despite the integral role of invertebrates in belowground systems, they are excluded from climate change models. Soil invertebrates have consumptive and nonconsumptive effects on microbes, whose respiration accounts for nearly half of soil CO 2 emissions. By altering the behavior and abundance of invertebrates that interact with microbes, invertebrate predators may have indirect effects on soil respiration. We examined the effects of a generalist arthropod predator on belowground respiration under different warming scenarios. Based on research suggesting invertebratesmore » may mediate soil CO 2 emission responses to warming, we predicted that predator presence would result in increased emissions by negatively affecting these invertebrates. We altered the presence of wolf spiders ( Pardosa spp.) in mesocosms containing a forest floor community. To simulate warming, we placed mesocosms of each treatment in ten open-top warming chambers ranging from 1.5° to 5.5°C above ambient at Harvard Forest, Massachusetts, USA. As expected, CO 2 emissions increased under warming and we found an interactive effect of predator presence and warming, although the effect was not consistent through time. The interaction between predator presence and warming was the inverse of our predictions: Mesocosms with predators had lower respiration at higher levels of warming than those without predators. Carbon dioxide emissions were not significantly associated with microbial biomass. Here, we did not find evidence of consumptive effects of predators on the invertebrate community, suggesting that predator presence mediates response of microbial respiration to warming through nonconsumptive means. In our system, we found a significant interaction between warming and predator presence that warrants further research into mechanism and

Predator contributions to belowground responses to warming

DOE PAGES

Maran, A. M.; Pelini, S. L.

2016-09-26

Identifying the factors that control soil CO 2 emissions will improve our ability to predict the magnitude of climate change–soil ecosystem feedbacks. Despite the integral role of invertebrates in belowground systems, they are excluded from climate change models. Soil invertebrates have consumptive and nonconsumptive effects on microbes, whose respiration accounts for nearly half of soil CO 2 emissions. By altering the behavior and abundance of invertebrates that interact with microbes, invertebrate predators may have indirect effects on soil respiration. We examined the effects of a generalist arthropod predator on belowground respiration under different warming scenarios. Based on research suggesting invertebratesmore » may mediate soil CO 2 emission responses to warming, we predicted that predator presence would result in increased emissions by negatively affecting these invertebrates. We altered the presence of wolf spiders ( Pardosa spp.) in mesocosms containing a forest floor community. To simulate warming, we placed mesocosms of each treatment in ten open-top warming chambers ranging from 1.5° to 5.5°C above ambient at Harvard Forest, Massachusetts, USA. As expected, CO 2 emissions increased under warming and we found an interactive effect of predator presence and warming, although the effect was not consistent through time. The interaction between predator presence and warming was the inverse of our predictions: Mesocosms with predators had lower respiration at higher levels of warming than those without predators. Carbon dioxide emissions were not significantly associated with microbial biomass. Here, we did not find evidence of consumptive effects of predators on the invertebrate community, suggesting that predator presence mediates response of microbial respiration to warming through nonconsumptive means. In our system, we found a significant interaction between warming and predator presence that warrants further research into mechanism and

Sustained acceleration of soil carbon decomposition observed in a 6-year warming experiment in a warm-temperate forest in southern Japan

PubMed Central

Teramoto, Munemasa; Liang, Naishen; Takagi, Masahiro; Zeng, Jiye; Grace, John

2016-01-01

To examine global warming’s effect on soil organic carbon (SOC) decomposition in Asian monsoon forests, we conducted a soil warming experiment with a multichannel automated chamber system in a 55-year-old warm-temperate evergreen broadleaved forest in southern Japan. We established three treatments: control chambers for total soil respiration, trenched chambers for heterotrophic respiration (Rh), and warmed trenched chambers to examine warming effect on Rh. The soil was warmed with an infrared heater above each chamber to increase soil temperature at 5 cm depth by about 2.5 °C. The warming treatment lasted from January 2009 to the end of 2014. The annual warming effect on Rh (an increase per °C) ranged from 7.1 to17.8% °C−1. Although the warming effect varied among the years, it averaged 9.4% °C−1 over 6 years, which was close to the value of 10.1 to 10.9% °C−1 that we calculated using the annual temperature–efflux response model of Lloyd and Taylor. The interannual warming effect was positively related to the total precipitation in the summer period, indicating that summer precipitation and the resulting soil moisture level also strongly influenced the soil warming effect in this forest. PMID:27748424

Southern Hemisphere and deep-sea warming led deglacial atmospheric CO2 rise and tropical warming.

PubMed

Stott, Lowell; Timmermann, Axel; Thunell, Robert

2007-10-19

Establishing what caused Earth's largest climatic changes in the past requires a precise knowledge of both the forcing and the regional responses. We determined the chronology of high- and low-latitude climate change at the last glacial termination by radiocarbon dating benthic and planktonic foraminiferal stable isotope and magnesium/calcium records from a marine core collected in the western tropical Pacific. Deep-sea temperatures warmed by approximately 2 degrees C between 19 and 17 thousand years before the present (ky B.P.), leading the rise in atmospheric CO2 and tropical-surface-ocean warming by approximately 1000 years. The cause of this deglacial deep-water warming does not lie within the tropics, nor can its early onset between 19 and 17 ky B.P. be attributed to CO2 forcing. Increasing austral-spring insolation combined with sea-ice albedo feedbacks appear to be the key factors responsible for this warming.

What happens during vocal warm-up?

PubMed

Elliot, N; Sundberg, J; Gramming, P

1995-03-01

Most singers prefer to warm up their voices before performing. Although the subjective effect is often considerable, the underlying physiological effects are largely unknown. Because warm-up tends to increase blood flow in muscles, it seems likely that vocal warm-up might induce decreased viscosity in the vocal folds. According to the theory of vocal-fold vibration, such a decrease should lead to a lower phonation threshold pressure. In this investigation the effect of vocal warm-up on the phonation threshold pressure was examined in a group of male and female singers. The effect varied considerably between subjects, presumably because the vocal-fold viscosity was not a dominating factor for the phonation-threshold pressure.

Reliability of Current Biokinetic and Dosimetric Models for Radionuclides: A Pilot Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leggett, Richard Wayne; Eckerman, Keith F; Meck, Robert A.

2008-10-01

This report describes the results of a pilot study of the reliability of the biokinetic and dosimetric models currently used by the U.S. Nuclear Regulatory Commission (NRC) as predictors of dose per unit internal or external exposure to radionuclides. The study examines the feasibility of critically evaluating the accuracy of these models for a comprehensive set of radionuclides of concern to the NRC. Each critical evaluation would include: identification of discrepancies between the models and current databases; characterization of uncertainties in model predictions of dose per unit intake or unit external exposure; characterization of variability in dose per unit intakemore » or unit external exposure; and evaluation of prospects for development of more accurate models. Uncertainty refers here to the level of knowledge of a central value for a population, and variability refers to quantitative differences between different members of a population. This pilot study provides a critical assessment of models for selected radionuclides representing different levels of knowledge of dose per unit exposure. The main conclusions of this study are as follows: (1) To optimize the use of available NRC resources, the full study should focus on radionuclides most frequently encountered in the workplace or environment. A list of 50 radionuclides is proposed. (2) The reliability of a dose coefficient for inhalation or ingestion of a radionuclide (i.e., an estimate of dose per unit intake) may depend strongly on the specific application. Multiple characterizations of the uncertainty in a dose coefficient for inhalation or ingestion of a radionuclide may be needed for different forms of the radionuclide and different levels of information of that form available to the dose analyst. (3) A meaningful characterization of variability in dose per unit intake of a radionuclide requires detailed information on the biokinetics of the radionuclide and hence is not feasible for many

TOPEX/El Nino Watch - El Nino Warm Water Pool Returns to Near Normal State, Mar, 14, 1998

NASA Technical Reports Server (NTRS)

1998-01-01

This image of the Pacific Ocean was produced using sea surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Mar. 14, 1998 and sea surface height is an indicator of the heat content of the ocean. The image shows that the sea surface height along the central equatorial Pacific has returned to a near normal state. Oceanographers indicate this is a classic pattern, typical of a mature El Nino condition. Remnants of the El Nino warm water pool, shown in red and white, are situated to the north and south of the equator. These sea surface height measurements have provided scientists with a detailed view of how the 1997-98 El Nino's warm pool behaves because the TOPEX/Poseidon satellite measures the changing sea surface height with unprecedented precision. In this image, the white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal; in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level. The El Nino phenomenon is thought to be triggered when the steady westward blowing trade winds weaken and even reverse direction. This change in the winds allows a large mass of warm water (the red and white area) that is normally located near Australia to move eastward along the equator until it reaches the coast of South America. The displacement of so much warm water affects evaporation, where rain clouds form and, consequently, alters the typical atmospheric jet stream patterns around the world. Using satellite imagery, buoy and ship data, and a forecasting model of the ocean-atmosphere system, the National Oceanic and Atmospheric Administration, (NOAA), has continued to issue an advisory indicating the so-called El Nino weather

Added prognostic value of ischaemic threshold in radionuclide myocardial perfusion imaging: a common-sense integration of exercise tolerance and ischaemia severity.

PubMed

Marini, Cecilia; Acampa, Wanda; Bauckneht, Matteo; Daniele, Stefania; Capitanio, Selene; Cantoni, Valeria; Fiz, Francesco; Zampella, Emilia; Dib, Bassam; Assante, Roberta; Bruzzi, Paolo; Sambuceti, Gianmario; Cuocolo, Alberto

2015-04-01

Reversible ischaemia at radionuclide myocardial perfusion imaging (MPI) accurately predicts risk of cardiac death and nonfatal myocardial infarction (major adverse cardiac events, MACE). This prognostic penetrance might be empowered by accounting for exercise tolerance as an indirect index of ischaemia severity. The present study aimed to verify this hypothesis integrating imaging assessment of ischaemia severity with exercise maximal rate pressure product (RPP) in a large cohort of patients with suspected or known coronary artery disease (CAD). We analysed 1,502 consecutive patients (1,014 men aged 59 ± 10 years) submitted to exercise stress/rest MPI. To account for exercise tolerance, the summed difference score (SDS) was divided by RPP at tracer injection providing a clinical prognostic index (CPI). Reversible ischaemia was documented in 357 patients (24 %) and was classified by SDS as mild (SDS 2-4) in 180, moderate (SDS 5-7) in 118 and severe (SDS >7) in 59. CPI values of ischaemic patients were clustered into tertiles with lowest and highest values indicating low and high risk, respectively. CPI modified SDS risk prediction in 119/357 (33 %) patients. During a 60-month follow-up, MACE occurred in 68 patients. Kaplan-Meier analysis revealed that CPI significantly improved predictive power for MACE incidence with respect to SDS alone. Multivariate Cox analysis confirmed the additive independent value of CPI-derived information. Integration of ischaemic threshold and ischaemia extension and severity can improve accuracy of exercise MPI in predicting long-term outcome in a large cohort of patients with suspected or known CAD.

Radionuclide Transport in Fracture-Granite Interface Zones

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Q; Mori, A

In situ radionuclide migration experiments, followed by excavation and sample characterization, were conducted in a water-conducting shear zone at the Grimsel Test Site (GTS) in Switzerland to study diffusion paths of radionuclides in fractured granite. In this work, we employed a micro-scale mapping technique that interfaces laser ablation sampling with inductively coupled plasma-mass spectrometry (LA/ICP-MS) to measure the fine-scale (micron-range) distribution of actinides ({sup 234}U, {sup 235}U, and {sup 237}Np) in the fracture-granite interface zones. Long-lived {sup 234}U, {sup 235}U, and {sup 237}Np were detected in flow channels, as well as in the adjacent rock matrix, using the sensitive, feature-basedmore » mapping of the LA/ICP-MS technique. The injected sorbing actinides are mainly located within the advective flowing fractures and the immediately adjacent regions. The water-conducting fracture studied in this work is bounded on one side by mylonite and the other by granitic matrix regions. These actinides did not penetrate into the mylonite side as much as the relatively higher-porosity granite matrix, most likely due to the low porosity, hydraulic conductivity, and diffusivity of the fracture wall (a thickness of about 0.4 mm separates the mylonite region from the fracture) and the mylonite region itself. Overall, the maximum penetration depth detected with this technique for the more diffusive {sup 237}Np over the field experimental time scale of about 60 days was about 10 mm in the granitic matrix, illustrating the importance of matrix diffusion in retarding radionuclide transport from the advective fractures. Laboratory tests and numerical modeling of radionuclide diffusion into granitic matrix was conducted to complement and help interpret the field results. Measured apparent diffusivity of multiple tracers in granite provided consistent predictions for radionuclide transport in the fractured granitic rock.« less

Arctic Security in a Warming World

DTIC Science & Technology

2010-03-01

2009). 3 Map based on: “Northwest Passage - Map of Arctic Sea Ice: Global Warming is Opening Canada’s Arctic” http://geology.com/articles/northwest...War College, February 17, 2009) 3. 5 Scott G. Borgerson, “Arctic Meltdown: the Economic and Security Implications of Global Warming ”, Foreign Affairs...april/kirkpatrick.pdf (accessed February 10, 2010). 45 Thomas R. McCarthy, Jr., Global Warming Threatens National Interests in the Arctic, Strategy

Natural Radionuclide Activity Concentrations In Spas Of Argentina

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gnoni, G.; Czerniczyniec, M.; Canoba, A.

2008-08-07

Geothermal waters have been used on a large scale for bathing, drinking and medical purposes. These waters can contain natural radionuclides that may increase the exposure to people. In this work the most important natural radionuclide activity concentrations in different thermal spas of Argentina were measured to characterize waters and to evaluate the exposure of workers and members of the public.

Warming Seas and Melting Ice Sheets

NASA Image and Video Library

2017-12-08

Sea level rise is a natural consequence of the warming of our planet. We know this from basic physics. When water heats up, it expands. So when the ocean warms, sea level rises. When ice is exposed to heat, it melts. And when ice on land melts and water runs into the ocean, sea level rises. For thousands of years, sea level has remained relatively stable and human communities have settled along the planet’s coastlines. But now Earth’s seas are rising. Globally, sea level has risen about eight inches since the beginning of the 20th century and more than two inches in the last 20 years alone. All signs suggest that this rise is accelerating. Read more: go.nasa.gov/1heZn29 Caption: An iceberg floats in Disko Bay, near Ilulissat, Greenland, on July 24, 2015. The massive Greenland ice sheet is shedding about 300 gigatons of ice a year into the ocean, making it the single largest source of sea level rise from melting ice. Credits: NASA/Saskia Madlener NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Simulating Radionuclide Migrations of Low-level Wastes in Nearshore Environment

NASA Astrophysics Data System (ADS)

Lu, C. C.; Li, M. H.; Chen, J. S.; Yeh, G. T.

2016-12-01

Tunnel disposal into nearshore mountains was tentatively selected as one of final disposal sites for low-level wastes in Taiwan. Safety assessment on radionuclide migrations in far-filed may involve geosphere processes under coastal environments and into nearshore ocean. In this study the 3-D HYDROFEOCHE5.6 numerical model was used to perform simulations of groundwater flow and radionuclide transport with decay chains. Domain of interest on the surface includes nearby watersheds delineated by digital elevation models and nearshore seabed. As deep as 800 m below the surface and 400 m below sea bed were considered for simulations. The disposal site was located at 200m below the surface. Release rates of radionuclides from near-field was estimated by analytical solutions of radionuclide diffusion with decay out of engineered barriers. Far-field safety assessments were performed starting from the release of radionuclides out of engineered barriers to a time scale of 10,000 years. Sensitivity analyses of geosphere and transport parameters were performed to improve our understanding of safety on final disposal of low-level waste in nearshore environments.

Warm Hands and Feet

NASA Technical Reports Server (NTRS)

1976-01-01

Comfort Products, Inc. was responsible for the cold weather glove and thermal boots, adapted from a spacesuit design that kept astronauts warm or cool in the temperature extremes of the Apollo Moon Mission. Gloves and boots are thermally heated. Batteries are worn inside wrist of glove or sealed in sole of skiboot and are rechargeable hundreds of times. They operate flexible resistance circuit which is turned on periodically when wearer wants to be warm.

Plant inputs, microbial carbon use in soil and decomposition under warming: effects of warming are depth dependent

NASA Astrophysics Data System (ADS)

Pendall, E.; Carrillo, Y.; Dijkstra, F. A.

2017-12-01

Future climate will include warmer conditions but impacts on soil C cycling remain uncertain and so are the potential warming-driven feedbacks. Net impacts will depend on the balance of effects on microbial activity and plant inputs. Soil depth is likely to be a critical factor driving this balance as it integrates gradients in belowground biomass, microbial activity and environmental variables. Most empirical studies focus on one soil layer and soil C forecasting relies on broad assumptions about effects of depth. Our limited understanding of the use of available C by soil microbes under climate change across depths is a critical source of uncertainty. Long-term labelling of plant biomass with C isotopic tracers in intact systems allows us to follow the dynamics of different soil C pools including the net accumulation of newly fixed C and the net loss of native C. These can be combined with concurrent observations of microbial use of C pools to explore the impacts of depth on the relationships between plant inputs and microbial C use. We evaluated belowground biomass, in-situ root decomposition and incorporation of plant-derived C into soil C and microbial C at 0-5 cm and 5-15 cmover 7 years at the Prairie Heating And CO2 Enrichment experiment. PHACE was a factorial manipulation of CO2 and warming in a native mixed grass prairie in Wyoming, USA. We used the continuous fumigation with labelled CO2 in the elevated CO2 treatments to study the C dynamics under unwarmed and warmed conditions. Shallower soils had three times the density of biomass as deeper soils. Warming increased biomass in both depths but this effect was weaker in deeper soils. Root litter mass loss in deeper soil was one third that of the shallow and was not affected by warming. Consistent with biomass distribution, incorporation of plant-derived C into soil and microbial C was lower in deeper soils and higher with warming. However, in contrast to the effect of warming on biomass, the effect of

Warm Absorber Diagnostics of AGN Dynamics

NASA Astrophysics Data System (ADS)

Kallman, Timothy

Warm absorbers and related phenomena are observable manifestations of outflows or winds from active galactic nuclei (AGN) that have great potential value. Understanding AGN outflows is important for explaining the mass budgets of the central accreting black hole, and also for understanding feedback and the apparent co-evolution of black holes and their host galaxies. In the X-ray band warm absorbers are observed as photoelectric absorption and resonance line scattering features in the 0.5-10 keV energy band; the UV band also shows resonance line absorption. Warm absorbers are common in low luminosity AGN and they have been extensively studied observationally. They may play an important role in AGN feedback, regulating the net accretion onto the black hole and providing mechanical energy to the surroundings. However, fundamental properties of the warm absorbers are not known: What is the mechanism which drives the outflow?; what is the gas density in the flow and the geometrical distribution of the outflow?; what is the explanation for the apparent relation between warm absorbers and the surprising quasi-relativistic 'ultrafast outflows' (UFOs)? We propose a focused set of model calculations that are aimed at synthesizing observable properties of warm absorber flows and associated quantities. These will be used to explore various scenarios for warm absorber dynamics in order to answer the questions in the previous paragraph. The guiding principle will be to examine as wide a range as possible of warm absorber driving mechanisms, geometry and other properties, but with as careful consideration as possible to physical consistency. We will build on our previous work, which was a systematic campaign for testing important class of scenarios for driving the outflows. We have developed a set of tools that are unique and well suited for dynamical calculations including radiation in this context. We also have state-of-the-art tools for generating synthetic spectra, which are

Warming trends: Adapting to nonlinear change

DOE PAGES

Jonko, Alexandra K.

2015-01-28

As atmospheric carbon dioxide concentrations rise, some regions are expected to warm more than others. Research suggests that whether warming will intensify or slow down over time also depends on location.

Cerebrospinal fluid leakage in intracranial hypotension syndrome: usefulness of indirect findings in radionuclide cisternography for detection and treatment monitoring.

PubMed

Morioka, Tomoaki; Aoki, Takatoshi; Tomoda, Yoshinori; Takahashi, Hiroyuki; Kakeda, Shingo; Takeshita, Iwao; Ohno, Masato; Korogi, Yukunori

2008-03-01

To evaluate indirect findings of cerebrospinal fluid (CSF) leakage on radionuclide cisternography and their changes after treatment. This study was approved by the hospital's institutional review board and informed consent was obtained before each examination. A total of 67 patients who were clinically suspected of spontaneous intracranial hypotension (SIH) syndrome underwent radionuclide cisternography, and 27 patients who had direct findings of CSF leakage on radionuclide cisternography were selected for this evaluation. They were 16 males and 11 females, aged between 26 and 58 years. Sequential images of radionuclide cisternography were acquired at 1, 3, 5, and 24 hours after injection. We assessed the presence or absence of 4 indirect findings; early visualization of bladder activity, no visualization of activity over the brain convexities, rapid disappearance of spinal activity, and abnormal visualization of the root sleeves. Changes of the direct and indirect findings after treatment were also evaluated in 14 patients who underwent epidural blood patch treatment. Early visualization of bladder activity was found in all 27 patients. Seven of 27 (25.9%) patients showed no activity over the brain convexities. Rapid disappearance of spinal activity and abnormal root sleeve visualization were present in 2 (7.4%) and 5 (18.5%) patients, respectively. After epidural blood patch, both direct CSF leakage findings and indirect findings of early visualization of bladder activity had disappeared or improved in 12 of 14 patients (85.7%). The other indirect findings also disappeared after treatment in all cases. Indirect findings of radionuclide cisternography, especially early visualization of bladder activity, may be useful in the diagnosis and posttreatment follow-up of CSF leakage.

The interference of medical radionuclides with occupational in vivo gamma spectrometry.

PubMed

Kol, R; Pelled, O; Canfi, A; Gilad, Y; German, U; Laichter, Y; Lantsberg, S; Fuksbrauner, R; Gold, B

2003-06-01

Radiation workers undergo routine monitoring for the evaluation of external and internal radiation exposures. The monitoring of internal exposures involves gamma spectrometry of the whole body (whole body counting) and measurements of excreta samples. Medical procedures involving internal administration of radioactive radionuclides are widely and commonly used. Medical radionuclides are typically short-lived, but high activities are generally administered, whereas occupational radionuclides are mostly long-lived and, if present, are found generally in relatively smaller quantities. The aim of the present work was to study the interference of some common medical radionuclides (201Tl, 9mTc, 57Co, and 131I) with the detection of internal occupational exposures to natural uranium and to 137Cs. Workers having undergone a medical procedure with one of the radionuclides mentioned above were asked to give frequent urine samples and to undergo whole body and thyroid counting with phoswich detectors operated at the Nuclear Research Center Negev. Urine and whole body counting monitoring were continued as long as radioactivity was detectable by gamma spectrometry. The results indicate that the activity of medical radionuclides may interfere with interpretation of occupational intakes for months after administration.

Global metabolic impacts of recent climate warming.

PubMed

Dillon, Michael E; Wang, George; Huey, Raymond B

2010-10-07

Documented shifts in geographical ranges, seasonal phenology, community interactions, genetics and extinctions have been attributed to recent global warming. Many such biotic shifts have been detected at mid- to high latitudes in the Northern Hemisphere-a latitudinal pattern that is expected because warming is fastest in these regions. In contrast, shifts in tropical regions are expected to be less marked because warming is less pronounced there. However, biotic impacts of warming are mediated through physiology, and metabolic rate, which is a fundamental measure of physiological activity and ecological impact, increases exponentially rather than linearly with temperature in ectotherms. Therefore, tropical ectotherms (with warm baseline temperatures) should experience larger absolute shifts in metabolic rate than the magnitude of tropical temperature change itself would suggest, but the impact of climate warming on metabolic rate has never been quantified on a global scale. Here we show that estimated changes in terrestrial metabolic rates in the tropics are large, are equivalent in magnitude to those in the north temperate-zone regions, and are in fact far greater than those in the Arctic, even though tropical temperature change has been relatively small. Because of temperature's nonlinear effects on metabolism, tropical organisms, which constitute much of Earth's biodiversity, should be profoundly affected by recent and projected climate warming.

Global warming: Clouds cooled the Earth

NASA Astrophysics Data System (ADS)

Mauritsen, Thorsten

2016-12-01

The slow instrumental-record warming is consistent with lower-end climate sensitivity. Simulations and observations now show that changing sea surface temperature patterns could have affected cloudiness and thereby dampened the warming.

[Startup mechanism of moxibustion warming and dredging function].

PubMed

Huang, Kaiyu; Liang, Shuang; Sun, Zheng; Zhang, Jianbin

2017-09-12

With "moxibustion" and "warm stimulation" as the keywords, the literature on moxibustion mechanism of warming and dredging from June 1st, 1995 to June 1st, 2016 was collected from PubMed, China National Knowledge Infrastructure (CNKI) and Wanfang database. The startup mechanism of moxibustion warming and dredging function was analyzed in terms of moxibustion warming stimulation. The results were found that moxibustion was based on local rising temperature of acupoint. It activated local specific receptors, heat sensitive immune cells, heat shock proteins and so on to start the warming and dredging function and produce various local effects. The warming stimulation signals as well as subsequent effects through nerve and body fluid pathways induced the effects of further specific target organs and body systems.

New radionuclide agents for cardiac imaging: Description and application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kahn, J.K.; Pippin, J.J.; Corbett, J.R.

1989-08-01

The introduction of three new radiopharmaceuticals into clinical research and practice has broadened the potential applications and scope of nuclear cardiology examinations. Technetium-99m labeled isonitrile perfusion agents have excellent imaging characteristics allowing the accurate identification of coronary artery disease. Simultaneous assessments of ventricular function are possible with these agents. Iodine-123 phenylpentadecanoic acid myocardial scintigraphy permits assessments of myocardial perfusion and fatty acid metabolism, and permits investigations of myocardial metabolism with conventional imaging equipment. Iodine-123 meta-iodobenzyl-guanidine serves as an indicator of the functional integrity of the sympathetic nervous system and permits evaluations of the effects of various disease states on catecholaminemore » handling by the heart. 58 references.« less

Why tropical forest lizards are vulnerable to climate warming.

PubMed

Huey, Raymond B; Deutsch, Curtis A; Tewksbury, Joshua J; Vitt, Laurie J; Hertz, Paul E; Alvarez Pérez, Héctor J; Garland, Theodore

2009-06-07

Biological impacts of climate warming are predicted to increase with latitude, paralleling increases in warming. However, the magnitude of impacts depends not only on the degree of warming but also on the number of species at risk, their physiological sensitivity to warming and their options for behavioural and physiological compensation. Lizards are useful for evaluating risks of warming because their thermal biology is well studied. We conducted macrophysiological analyses of diurnal lizards from diverse latitudes plus focal species analyses of Puerto Rican Anolis and Sphaerodactyus. Although tropical lowland lizards live in environments that are warm all year, macrophysiological analyses indicate that some tropical lineages (thermoconformers that live in forests) are active at low body temperature and are intolerant of warm temperatures. Focal species analyses show that some tropical forest lizards were already experiencing stressful body temperatures in summer when studied several decades ago. Simulations suggest that warming will not only further depress their physiological performance in summer, but will also enable warm-adapted, open-habitat competitors and predators to invade forests. Forest lizards are key components of tropical ecosystems, but appear vulnerable to the cascading physiological and ecological effects of climate warming, even though rates of tropical warming may be relatively low.

Why tropical forest lizards are vulnerable to climate warming

PubMed Central

Huey, Raymond B.; Deutsch, Curtis A.; Tewksbury, Joshua J.; Vitt, Laurie J.; Hertz, Paul E.; Álvarez Pérez, Héctor J.; Garland, Theodore

2009-01-01

Biological impacts of climate warming are predicted to increase with latitude, paralleling increases in warming. However, the magnitude of impacts depends not only on the degree of warming but also on the number of species at risk, their physiological sensitivity to warming and their options for behavioural and physiological compensation. Lizards are useful for evaluating risks of warming because their thermal biology is well studied. We conducted macrophysiological analyses of diurnal lizards from diverse latitudes plus focal species analyses of Puerto Rican Anolis and Sphaerodactyus. Although tropical lowland lizards live in environments that are warm all year, macrophysiological analyses indicate that some tropical lineages (thermoconformers that live in forests) are active at low body temperature and are intolerant of warm temperatures. Focal species analyses show that some tropical forest lizards were already experiencing stressful body temperatures in summer when studied several decades ago. Simulations suggest that warming will not only further depress their physiological performance in summer, but will also enable warm-adapted, open-habitat competitors and predators to invade forests. Forest lizards are key components of tropical ecosystems, but appear vulnerable to the cascading physiological and ecological effects of climate warming, even though rates of tropical warming may be relatively low. PMID:19324762

Diffusion of Radionuclides in Concrete and Soil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mattigod, Shas V.; Wellman, Dawn M.; Bovaird, Chase C.

2012-04-25

One of the methods being considered for safely disposing of Category 3 low-level radioactive wastes is to encase the waste in concrete. Such concrete encasement would contain and isolate the waste packages from the hydrologic environment and would act as an intrusion barrier. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages. The mobilized radionuclides may escape from the encased concrete by mass flow and/or diffusion and move into the surrounding subsurface environment. Therefore, it is necessary to assess the performance of the concrete encasement structure and the ability ofmore » the surrounding soil to retard radionuclide migration. The objective of our study was to measure the diffusivity of Re, Tc and I in concrete containment and the surrounding vadose zone soil. Effects of carbonation, presence of metallic iron, and fracturing of concrete and the varying moisture contents in soil on the diffusivities of Tc and I were evaluated.« less

Radionuclides in drinking water: the recent legislative requirements of the European Union.

PubMed

Grande, Sveva; Risica, Serena

2015-03-01

In November 2013, a new EURATOM Directive was issued on the protection of public health from the radionuclide content in drinking water. After introducing the contents of the Directive, the paper analyses the hypotheses about drinking water ingestion adopted in documents of international and national organizations and the data obtained from national/regional surveys. Starting from the Directive's parametric value for the Indicative Dose, some examples of derived activity concentrations of radionuclides in drinking water are reported for some age classes and three exposure situations, namely, (i) artificial radionuclides due to routine water release from nuclear power facilities, (ii) artificial radionuclides from nuclear medicine procedures, and (iii) naturally occurring radionuclides in drinking water or resulting from existing or past NORM industrial activities.

Analysis of data from spacecraft (stratospheric warmings)

NASA Technical Reports Server (NTRS)

1974-01-01

The details of the stratospheric warming processes as to time, area, and intensity were established, and the warmings with other terrestrial and solar phenomena occurring at satellite platform altitudes, or observable from satellite platforms, were correlated. Links were sought between the perturbed upper atmosphere (mesosphere and thermosphere) and the stratosphere that might explain stratospheric warmings.

Radionuclide evaluation of free vascularized bone graft viability. [/sup 99m/Tc-methylene diphosphonate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lisbona, R.; Rennie, W.R.J.; Daniel, R.K.

1980-02-01

Free vascularized bone grafting is a new technique applied to the reconstructive surgery of long bones affected by aggressive benign or malignant processes, as well as traumatic deficiencies. These bone lesions may be treated by en bloc excision and replacement with fibular segments or osteocutaneous flaps from the groin isolated on their vascular pedicle. Microvascular anastomosis of the pedicle at the recipient site is necessary. Radionuclide bone imaging is unique in the assessment of the free vascularized bone graft because postoperative graft uptake of radiopharmaceutical reflects patent anastomoses and segmental bone viability.

A warm Spitzer survey of the LSST/DES 'Deep drilling' fields

NASA Astrophysics Data System (ADS)

Lacy, Mark; Farrah, Duncan; Brandt, Niel; Sako, Masao; Richards, Gordon; Norris, Ray; Ridgway, Susan; Afonso, Jose; Brunner, Robert; Clements, Dave; Cooray, Asantha; Covone, Giovanni; D'Andrea, Chris; Dickinson, Mark; Ferguson, Harry; Frieman, Joshua; Gupta, Ravi; Hatziminaoglou, Evanthia; Jarvis, Matt; Kimball, Amy; Lubin, Lori; Mao, Minnie; Marchetti, Lucia; Mauduit, Jean-Christophe; Mei, Simona; Newman, Jeffrey; Nichol, Robert; Oliver, Seb; Perez-Fournon, Ismael; Pierre, Marguerite; Rottgering, Huub; Seymour, Nick; Smail, Ian; Surace, Jason; Thorman, Paul; Vaccari, Mattia; Verma, Aprajita; Wilson, Gillian; Wood-Vasey, Michael; Cane, Rachel; Wechsler, Risa; Martini, Paul; Evrard, August; McMahon, Richard; Borne, Kirk; Capozzi, Diego; Huang, Jiashang; Lagos, Claudia; Lidman, Chris; Maraston, Claudia; Pforr, Janine; Sajina, Anna; Somerville, Rachel; Strauss, Michael; Jones, Kristen; Barkhouse, Wayne; Cooper, Michael; Ballantyne, David; Jagannathan, Preshanth; Murphy, Eric; Pradoni, Isabella; Suntzeff, Nicholas; Covarrubias, Ricardo; Spitler, Lee

2014-12-01

We propose a warm Spitzer survey to microJy depth of the four predefined Deep Drilling Fields (DDFs) for the Large Synoptic Survey Telescope (LSST) (three of which are also deep drilling fields for the Dark Energy Survey (DES)). Imaging these fields with warm Spitzer is a key component of the overall success of these projects, that address the 'Physics of the Universe' theme of the Astro2010 decadal survey. With deep, accurate, near-infrared photometry from Spitzer in the DDFs, we will generate photometric redshift distributions to apply to the surveys as a whole. The DDFs are also the areas where the supernova searches of DES and LSST are concentrated, and deep Spitzer data is essential to obtain photometric redshifts, stellar masses and constraints on ages and metallicities for the >10000 supernova host galaxies these surveys will find. This 'DEEPDRILL' survey will also address the 'Cosmic Dawn' goal of Astro2010 through being deep enough to find all the >10^11 solar mass galaxies within the survey area out to z~6. DEEPDRILL will complete the final 24.4 square degrees of imaging in the DDFs, which, when added to the 14 square degrees already imaged to this depth, will map a volume of 1-Gpc^3 at z>2. It will find ~100 > 10^11 solar mass galaxies at z~5 and ~40 protoclusters at z>2, providing targets for JWST that can be found in no other way. The Spitzer data, in conjunction with the multiwavelength surveys in these fields, ranging from X-ray through far-infrared and cm-radio, will comprise a unique legacy dataset for studies of galaxy evolution.

Scaling Potential Evapotranspiration with Greenhouse Warming (Invited)

NASA Astrophysics Data System (ADS)

Scheff, J.; Frierson, D. M.

2013-12-01

Potential evapotranspiration (PET) is a supply-independent measure of the evaporative demand of a terrestrial climate, of basic importance in climatology, hydrology, and agriculture. Future increases in PET from greenhouse warming are often cited as key drivers of global trends toward drought and aridity. The present work computes recent and business-as-usual-future Penman-Monteith (i.e. physically-based) PET fields at 3-hourly resolution in 14 modern global climate models. The %-change in local annual-mean PET over the upcoming century is almost always positive, modally low double-digit in magnitude, usually increasing with latitude, yet quite divergent between models. These patterns are understood as follows. In every model, the global field of PET %-change is found to be dominated by the direct, positive effects of constant-relative-humidity warming (via increasing vapor pressure deficit and increasing Clausius-Clapeyron slope.) This direct-warming term very accurately scales as the PET-weighted (warm-season daytime) local warming, times 5-6% per degree (related to the Clausius-Clapeyron equation), times an analytic factor ranging from about 0.25 in warm climates to 0.75 in cold climates, plus a small correction. With warming of several degrees, this product is of low double-digit magnitude, and the strong temperature dependence gives the latitude dependence. Similarly, the inter-model spread in the amount of warming gives most of the spread in this term. Additional spread in the total change comes from strong disagreement on radiation, relative-humidity, and windspeed changes, which make smaller yet substantial contributions to the full PET %-change fields.

Radionuclides from past uranium mining in rivers of Portugal.

PubMed

Carvalho, Fernando P; Oliveira, João M; Lopes, Irene; Batista, Aleluia

2007-01-01

During several decades and until a few years ago, uranium mines were exploited in the Centre of Portugal and wastewaters from uranium ore milling facilities were discharged into river basins. To investigate enhancement of radioactivity in freshwater ecosystems, radionuclides of uranium and thorium series were measured in water, sediments, suspended matter, and fish samples from the rivers Vouga, Dão, Távora and Mondego. The results show that these rivers carry sediments with relatively high naturally occurring radioactivity, and display relatively high concentrations of radon dissolved in water, which is typical of a uranium rich region. Riverbed sediments show enhanced concentrations of radionuclides in the mid-section of the Mondego River, a sign of past wastewater discharges from mining and milling works at Urgeiriça confirmed by the enhanced values of (238)U/(232)Th radionuclide ratios in sediments. Radionuclide concentrations in water, suspended matter and freshwater fish from that section of Mondego are also enhanced in comparison with concentrations measured in other rivers. Based on current radionuclide concentrations in fish, regular consumption of freshwater species by local populations would add 0.032 mSv a(-1) of dose equivalent (1%) to the average background radiation dose. Therefore, it is concluded that current levels of enhanced radioactivity do not pose a significant radiological risk either to aquatic fauna or to freshwater fish consumers.

Ensemble Simulation of the Atmospheric Radionuclides Discharged by the Fukushima Nuclear Accident

NASA Astrophysics Data System (ADS)

Sekiyama, Thomas; Kajino, Mizuo; Kunii, Masaru

2013-04-01

Enormous amounts of radionuclides were discharged into the atmosphere by a nuclear accident at the Fukushima Daiichi nuclear power plant (FDNPP) after the earthquake and tsunami on 11 March 2011. The radionuclides were dispersed from the power plant and deposited mainly over eastern Japan and the North Pacific Ocean. A lot of numerical simulations of the radionuclide dispersion and deposition had been attempted repeatedly since the nuclear accident. However, none of them were able to perfectly simulate the distribution of dose rates observed after the accident over eastern Japan. This was partly due to the error of the wind vectors and precipitations used in the numerical simulations; unfortunately, their deterministic simulations could not deal with the probability distribution of the simulation results and errors. Therefore, an ensemble simulation of the atmospheric radionuclides was performed using the ensemble Kalman filter (EnKF) data assimilation system coupled with the Japan Meteorological Agency (JMA) non-hydrostatic mesoscale model (NHM); this mesoscale model has been used operationally for daily weather forecasts by JMA. Meteorological observations were provided to the EnKF data assimilation system from the JMA operational-weather-forecast dataset. Through this ensemble data assimilation, twenty members of the meteorological analysis over eastern Japan from 11 to 31 March 2011 were successfully obtained. Using these meteorological ensemble analysis members, the radionuclide behavior in the atmosphere such as advection, convection, diffusion, dry deposition, and wet deposition was simulated. This ensemble simulation provided the multiple results of the radionuclide dispersion and distribution. Because a large ensemble deviation indicates the low accuracy of the numerical simulation, the probabilistic information is obtainable from the ensemble simulation results. For example, the uncertainty of precipitation triggered the uncertainty of wet deposition; the

Warming Early Mars With CH4

NASA Astrophysics Data System (ADS)

Justh, H. L.; Kasting, J. F.

2002-12-01

The nature of the ancient climate of Mars remains one of the fundamental unresolved problems in martian research. While the present environment is hostile to life, images from the Mariner, Viking and Mars Global Surveyor missions, have shown geologic features on the martian surface that seem to indicate an earlier period of hydrologic activity. The fact that ancient valley networks and degraded craters have been seen on the martian surface indicates that the early martian climate may have been more Earth-like, with a warmer surface temperature. The presence of liquid water would require a greenhouse effect much larger than needed at present, as the solar constant, S0, was 25% lower 3.8 billion years ago when the channels are thought to have formed (1,2). Previous calculations have shown that gaseous CO2 and H2O alone could not have warmed the martian surface to the temperature needed to account for the presence of liquid water (3). It has been hypothesized that a CO2-H2O atmosphere could keep early Mars warm if it was filled with CO2 ice clouds in the upper martian troposphere (4). Obtaining mean martian surface temperatures above 273 K would require nearly 100% cloud cover, a condition that is unrealistic for condensation clouds on early Mars. Any reduction in cloud cover makes it difficult to achieve warm martian surface temperatures except at high pressures and CO2 clouds could cool the martian surface if they were low and optically thick (5). CO2 and CH4 have been suggested as important greenhouse gases on the early Earth. Our research focuses on the effects of increased concentrations of atmospheric greenhouse gases on the surface temperature of early Mars, with emphasis on the reduced greenhouse gas, CH4. To investigate the possible warming effect of CH4, we modified a one-dimensional, radiative-convective climate model used in previous studies of the early martian climate (5). New cloud-free temperature profiles for various surface pressures and CH4 mixing

Blodgett Forest Warming Experiment 1

DOE Data Explorer

Pries, Caitlin Hicks (ORCID:0000000308132211); Castanha, Cristina; Porras, Rachel; Torn, Margaret

2017-03-24

Carbon stocks and density fractions from soil pits used to characterize soils of the Blodgett warming experiment as well as gas well CO2, 13C, and 14C data from experimental plots. The experiment consisted of 3 control and heated plot pairs. The heated plots are warmed +4°C above the control from 10 to 100 cm.

A new approach to nuclear fuel safeguard enhancement through radionuclide profiling

NASA Astrophysics Data System (ADS)

Peterson, Aaron Dawon

The United States has led the effort to promote peaceful use of nuclear power amongst states actively utilizing it as well as those looking to deploy the technology in the near future. With the attraction being demonstrated by various countries towards nuclear power comes the concern that a nation may have military aspirations for the use of nuclear energy. The International Atomic Energy Agency (IAEA) has established nuclear safeguard protocols and procedures to mitigate nuclear proliferation. The work herein proposed a strategy to further enhance existing safeguard protocols by considering safeguard in nuclear fuel design. The strategy involved the use of radionuclides to profile nuclear fuels. Six radionuclides were selected as identifier materials. The decay and transmutation of these radionuclides were analyzed in reactor operation environment. MCNPX was used to simulate a reactor core. The perturbation in reactivity of the core due to the loading of the radionuclides was insignificant. The maximum positive and negative reactivity change induced was at day 1900 with a value of 0.00185 +/- 0.00256 and at day 2000 with -0.00441 +/- 0.00249, respectively. The mass of the radionuclides were practically unaffected by transmutation in the core; the change in radionuclide inventory was dominated by natural decay. The maximum material lost due to transmutation was 1.17% in Eu154. Extraneous signals from fission products identical to the radionuclide compromised the identifier signals. Eu154 saw a maximum intensity change at EOC and 30 days post-irradiation of 1260% and 4545%, respectively. Cs137 saw a minimum change of 12% and 89%, respectively. Mitigation of the extraneous signals is cardinal to the success of the proposed strategy. The predictability of natural decay provides a basis for the characterization of the signals from the radionuclide.

Mixing processes following the final stratospheric warming

NASA Technical Reports Server (NTRS)

Hess, Peter G.

1991-01-01

An investigation is made of the dynamics responsible for the mixing and dissolution of the polar vortex during the final stratospheric warmings. The dynamics and transport during a Northern Hemisphere final stratospheric warming are simulated via a GCM and an associated offline N2O transport model. The results are compared with those obtained from LIMS data for the final warming of 1979, with emphasis on the potential vorticity evolution in the two datasets, the modeled N2O evolution, and the observed O3 evolution. Following each warming, the remnants of the originally intact vortex are found to gradually homogenize with the atmosphere at large. Two processes leading to this homogenization are identified following the final warmings, namely, the potential vorticity field becomes decorrelated from that of the chemical tracer, and the vortex remnants begin to tilt dramatically in a vertical direction.

Bioremediation: a genuine technology to remediate radionuclides from the environment

PubMed Central

Prakash, Dhan; Gabani, Prashant; Chandel, Anuj K; Ronen, Zeev; Singh, Om V

2013-01-01

Summary Radionuclides in the environment are a major human and environmental health concern. Like the Chernobyl disaster of 1986, the Fukushima Daiichi nuclear disaster in 2011 is once again causing damage to the environment: a large quantity of radioactive waste is being generated and dumped into the environment, and if the general population is exposed to it, may cause serious life-threatening disorders. Bioremediation has been viewed as the ecologically responsible alternative to environmentally destructive physical remediation. Microorganisms carry endogenous genetic, biochemical and physiological properties that make them ideal agents for pollutant remediation in soil and groundwater. Attempts have been made to develop native or genetically engineered (GE) microbes for the remediation of environmental contaminants including radionuclides. Microorganism-mediated bioremediation can affect the solubility, bioavailability and mobility of radionuclides. Therefore, we aim to unveil the microbial-mediated mechanisms for biotransformation of radionuclides under various environmental conditions as developing strategies for waste management of radionuclides. A discussion follows of ‘-omics’-integrated genomics and proteomics technologies, which can be used to trace the genes and proteins of interest in a given microorganism towards a cell-free bioremediation strategy. PMID:23617701

Functional imaging of the brain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ell, P.J.; Jarritt, P.H.; Costa, D.C.

1987-07-01

The radionuclide tracer method is unique among all other imaging methodologies in its ability to trace organ or tissue function and metabolism. Physical processes such as electron or proton density assessment or resonance, edge identification, electrical or ultrasonic impedence, do not pertain to the image generation process in nuclear medicine, and if so, only in a rather secondary manner. The nuclear medicine imaging study is primarily a study of the chemical nature, distribution and interaction of the tracer/radiopharmaceutical utilized with the cellular system which requires investigation: the thyroid cells with sodium iodide, the recticular endothelial cells with colloidal particles, themore » adrenal medulla cells with metaiodobenzylguanidine, and so on. In the two most recent areas of nuclear medicine expansion, oncology (with labelled monoclonal antibodies) and neurology and psychiatry (with a whole new series of lipid soluble radiopharmaceuticals), specific cell systems can also be targeted and hence imaged and investigated. The study of structure as masterly performed by Virchow and all his successors over more than a century, is now definitely the prerogative of such imaging systems which excel with spatial and contrast resolution However the investigation of function and metabolism, has clearly passed from the laboratory animal protocol and experiment to the direct investigation in man, this being the achievement of the radionuclide tracer methodology. In this article, we review present interest and developments in that part of nuclear medicine activity which is aimed at the study of the neurological or psychiatric patient.« less

Promising prospects for 44Sc-/47Sc-based theragnostics: application of 47Sc for radionuclide tumor therapy in mice.

PubMed

Müller, Cristina; Bunka, Maruta; Haller, Stephanie; Köster, Ulli; Groehn, Viola; Bernhardt, Peter; van der Meulen, Nicholas; Türler, Andreas; Schibli, Roger

2014-10-01

In recent years, (47)Sc has attracted attention because of its favorable decay characteristics (half-life, 3.35 d; average energy, 162 keV; Eγ, 159 keV) for therapeutic application and for SPECT imaging. The aim of the present study was to investigate the suitability of (47)Sc for radionuclide therapy in a preclinical setting. For this purpose a novel DOTA-folate conjugate (cm10) with an albumin-binding entity was used. (47)Sc was produced via the (46)Ca(n,γ)(47)Ca[Formula: see text](47)Sc nuclear reaction at the high-flux reactor at the Institut Laue-Langevin. Separation of the (47)Sc from the target material was performed by a semi-automated process using extraction chromatography and cation exchange chromatography. (47)Sc-labeled cm10 was tested on folate receptor-positive KB tumor cells in vitro. Biodistribution and SPECT imaging experiments were performed in KB tumor-bearing mice. Radionuclide therapy was conducted with two groups of mice, which received either (47)Sc-cm10 (10 MBq) or only saline. Tumor growth and survival time were compared between the two groups of mice. Irradiation of (46)Ca resulted in approximately 1.8 GBq of (47)Ca, which subsequently decayed to (47)Sc. Separation of (47)Sc from (47)Ca was obtained with 80% yield in only 10 min. The (47)Sc was then available in a small volume (∼500 μL) of an ammonium acetate/HCl (pH 4.5) solution suitable for direct radiolabeling. (47)Sc-cm10 was prepared with a radiochemical yield of more than 96% at a specific activity of up to 13 MBq/nmol. In vitro (47)Sc-cm10 showed folate receptor-specific binding and uptake into KB tumor cells. In vivo SPECT/CT images allowed the visualization of accumulated radioactivity in KB tumors and in the kidneys. The therapy study showed a significantly delayed tumor growth in mice, which received (47)Sc-cm10 (10 MBq, 10 Gy) resulting in a more than 50% increase in survival time, compared with untreated control mice. With this study, we demonstrated the suitability of

Warm Arctic-cold Siberia: comparing the recent and the early 20th-century Arctic warmings

NASA Astrophysics Data System (ADS)

Wegmann, Martin; Orsolini, Yvan; Zolina, Olga

2018-02-01

The Warm Arctic-cold Siberia surface temperature pattern during recent boreal winter is suggested to be triggered by the ongoing decrease of Arctic autumn sea ice concentration and has been observed together with an increase in mid-latitude extreme events and a meridionalization of tropospheric circulation. However, the exact mechanism behind this dipole temperature pattern is still under debate, since model experiments with reduced sea ice show conflicting results. We use the early twentieth-century Arctic warming (ETCAW) as a case study to investigate the link between September sea ice in the Barents-Kara Sea (BKS) and the Siberian temperature evolution. Analyzing a variety of long-term climate reanalyses, we find that the overall winter temperature and heat flux trend occurs with the reduction of September BKS sea ice. Tropospheric conditions show a strengthened atmospheric blocking over the BKS, strengthening the advection of cold air from the Arctic to central Siberia on its eastern flank, together with a reduction of warm air advection by the westerlies. This setup is valid for both the ETCAW and the current Arctic warming period.

Selection of plants for phytoremediation of soils contaminated with radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Entry J.A.; Vance, N.C.; Watrud, L.S.

1996-12-31

Remediation of soil contaminated with radionuclides typically requires that soil be removed from the site and treated with various dispersing and chelating chemicals. Numerous studies have shown that radionuclides are generally not leached from the top 0.4 meters of soil, where plant roots actively accumulate elements. Restoration of large areas of land contaminated with low levels of radionuclides may be feasible using phytoremediation. Criteria for the selection of plants for phytoremediation, molecular approaches to increase radio nuclide uptake, effects of cultural practices on uptake and assessment of environmental effects of phytoremediation will be discussed.

Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation.

PubMed

McMurtry, G M; Schneider, R C; Colin, P L; Buddemeier, R W; Suchanek, T H

The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. Studies of the burial of fallout radionuclides have been conducted on the islands and in several of the large craters, but studies of their vertical distribution have been limited to about the upper 20 cm of the lagoon sediments. We have found elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

Seagrass ecophysiological performance under ocean warming and acidification.

PubMed

Repolho, Tiago; Duarte, Bernardo; Dionísio, Gisela; Paula, José Ricardo; Lopes, Ana R; Rosa, Inês C; Grilo, Tiago F; Caçador, Isabel; Calado, Ricardo; Rosa, Rui

2017-02-01

Seagrasses play an essential ecological role within coastal habitats and their worldwide population decline has been linked to different types of anthropogenic forces. We investigated, for the first time, the combined effects of future ocean warming and acidification on fundamental biological processes of Zostera noltii, including shoot density, leaf coloration, photophysiology (electron transport rate, ETR; maximum PSII quantum yield, F v /F m ) and photosynthetic pigments. Shoot density was severely affected under warming conditions, with a concomitant increase in the frequency of brownish colored leaves (seagrass die-off). Warming was responsible for a significant decrease in ETR and F v /F m (particularly under control pH conditions), while promoting the highest ETR variability (among experimental treatments). Warming also elicited a significant increase in pheophytin and carotenoid levels, alongside an increase in carotenoid/chlorophyll ratio and De-Epoxidation State (DES). Acidification significantly affected photosynthetic pigments content (antheraxanthin, β-carotene, violaxanthin and zeaxanthin), with a significant decrease being recorded under the warming scenario. No significant interaction between ocean acidification and warming was observed. Our findings suggest that future ocean warming will be a foremost determinant stressor influencing Z. noltii survival and physiological performance. Additionally, acidification conditions to occur in the future will be unable to counteract deleterious effects posed by ocean warming.

Seagrass ecophysiological performance under ocean warming and acidification

PubMed Central

Repolho, Tiago; Duarte, Bernardo; Dionísio, Gisela; Paula, José Ricardo; Lopes, Ana R.; Rosa, Inês C.; Grilo, Tiago F.; Caçador, Isabel; Calado, Ricardo; Rosa, Rui

2017-01-01

Seagrasses play an essential ecological role within coastal habitats and their worldwide population decline has been linked to different types of anthropogenic forces. We investigated, for the first time, the combined effects of future ocean warming and acidification on fundamental biological processes of Zostera noltii, including shoot density, leaf coloration, photophysiology (electron transport rate, ETR; maximum PSII quantum yield, Fv/Fm) and photosynthetic pigments. Shoot density was severely affected under warming conditions, with a concomitant increase in the frequency of brownish colored leaves (seagrass die-off). Warming was responsible for a significant decrease in ETR and Fv/Fm (particularly under control pH conditions), while promoting the highest ETR variability (among experimental treatments). Warming also elicited a significant increase in pheophytin and carotenoid levels, alongside an increase in carotenoid/chlorophyll ratio and De-Epoxidation State (DES). Acidification significantly affected photosynthetic pigments content (antheraxanthin, β-carotene, violaxanthin and zeaxanthin), with a significant decrease being recorded under the warming scenario. No significant interaction between ocean acidification and warming was observed. Our findings suggest that future ocean warming will be a foremost determinant stressor influencing Z. noltii survival and physiological performance. Additionally, acidification conditions to occur in the future will be unable to counteract deleterious effects posed by ocean warming. PMID:28145531

Tc-99m Labeled carrier for imaging

DOEpatents

Henze, Eberhard

1984-01-01

Novel radionuclide imaging agents, having particular application for lymphangiography are provided by non-covalently binding Tc-99m to a pharmaceutically acceptable cross-linked polysaccharide. Upon injection of the Tc-99m labeled polysaccharide into the blood stream, optimum contrast can be obtained within one hour.

The projected demise of Barnes Ice Cap: Evidence of an unusually warm 21st century Arctic

NASA Astrophysics Data System (ADS)

Gilbert, A.; Flowers, G. E.; Miller, G. H.; Refsnider, K. A.; Young, N. E.; Radić, V.

2017-03-01

As a remnant of the Laurentide Ice Sheet, Barnes Ice Cap owes its existence and present form in part to the climate of the last glacial period. The ice cap has been sustained in the present interglacial climate by its own topography through the mass balance-elevation feedback. A coupled mass balance and ice-flow model, forced by Coupled Model Intercomparison Project Phase 5 climate model output, projects that the current ice cap will likely disappear in the next 300 years. For greenhouse gas Representative Concentration Pathways of +2.6 to +8.5 Wm-2, the projected ice-cap survival times range from 150 to 530 years. Measured concentrations of cosmogenic radionuclides 10Be, 26Al, and 14C at sites exposed near the ice-cap margin suggest the pending disappearance of Barnes Ice Cap is very unusual in the last million years. The data and models together point to an exceptionally warm 21st century Arctic climate.

Delayed warming hiatus over the Tibetan Plateau

NASA Astrophysics Data System (ADS)

An, Wenling; Hou, Shugui; Hu, Yongyun; Wu, Shuangye

2017-03-01

A reduction in the warming rate for the global surface temperature since the late 1990s has attracted much attention and caused a great deal of controversy. During the same time period, however, most previous studies have reported enhanced warming over the Tibetan Plateau (TP). In this study we further examined the temperature trend of the TP and surrounding areas based on the homogenized temperature records for the period 1980-2014, we found that for the TP regions lower than 4000 m the warming rate has started to slow down since the late 1990s, a similar pattern consistent with the whole China and the global temperature trend. However, for the TP regions higher than 4000 m, this reduction in warming rate did not occur until the mid-2000s. This delayed warming hiatus could be related to changes in regional radiative, energy, and land surface processes in recent years.

Global Warming: How Much and Why?

ERIC Educational Resources Information Center

Lanouette, William

1990-01-01

Summarizes the history of the study of global warming and includes a discussion of the role of gases, like carbon dioxide, methane, and chlorofluorocarbon (CFC). Discusses modern research on the global warming, including computer modelling and the super-greenhouse effect. (YP)

Cancer radiotheranostics targeting carbonic anhydrase-IX with 111In- and 90Y-labeled ureidosulfonamide scaffold for SPECT imaging and radionuclide-based therapy

PubMed Central

Iikuni, Shimpei; Ono, Masahiro; Watanabe, Hiroyuki; Shimizu, Yoichi; Sano, Kohei; Saji, Hideo

2018-01-01

Hypoxic cells dynamically translocate during tumor growth and after radiotherapy. The most desirable direction for therapy targeting hypoxic cells is combining imaging and therapy (theranostics), which may help realize personalized medicine. Here, we conducted cancer radiotheranostics targeting carbonic anhydrase-IX (CA-IX), which is overexpressed in many kinds of hypoxic cancer cells, using low-molecular-weight 111In and 90Y complexes with a bivalent ureidosulfonamide scaffold as the CA-IX-binding moiety ([111In/90Y]US2). Methods: The targeting ability of [111In]US2 was evaluated by in vivo biodistribution study in CA-IX high-expressing (HT-29) tumor-bearing mice. In vivo imaging of HT-29 tumors was carried out using single photon emission computed tomography (SPECT). [90Y]US2 was administered to HT-29 tumor-bearing mice to evaluate cancer therapeutic effects. Results: [111In]US2 highly and selectively accumulated within HT-29 tumors (4.57% injected dose/g tumor at 1 h postinjection), was rapidly cleared from the blood pool and muscle after 4 h based on a biodistribution study, and visualized HT-29 tumor xenografts in mice at 4 h postinjection with SPECT. Radionuclide-based therapy with [90Y]US2 significantly delayed HT-29 tumor growth compared with that of untreated mice (P = 0.02 on day 28, Student's t-test), without any critical hematological toxicity due to its rapid pharmacokinetics. Conclusion: These results indicate that cancer radiotheranostics with [111In/90Y]US2 provides a novel strategy of theranostics for cancer hypoxia.

Characterization of Discharge Areas of Radionuclides Originating From Nuclear Waste Repositories

NASA Astrophysics Data System (ADS)

Marklund, L.; Xu, S.; Worman, A.

2009-05-01

If leakages in nuclear waste repositories located in crystalline bedrock arise, radionuclides will reach the biosphere and cause a risk of radiological impact. The extent of the radiological impact depends on in which landscape elements the radionuclides emerge. In this study, we investigate if there are certain landscape elements that generally will act as discharge areas for radionuclides leaking from subsurface deposits. We also characterize the typical properties that distinguish these areas from others. In humid regions, landscape topography is the most important driving force for groundwater flow. Because groundwater is the main transporting agent for migrating radionuclides, the topography will determine the flowpaths of leaking radionuclides. How topography and heterogeneities in the subsurface affect the discharge distribution of the radionuclides is therefore an important scope of this study. To address these issues, we developed a 3-D transport model. Our analyses are based on site-specific data from two different areas in Sweden, Forsmark, Uppland, and Oskarshamn, Småland. The Swedish Nuclear Waste Management Company (SKB) has selected these two areas as candidate areas for a deep repository of nuclear waste and the areas are currently subject to site investigations. Our results suggest that there are hot-spots in the landscape i.e. areas with high probability of receiving large amounts of radionuclides from a leaking repository of nuclear waste. The hot-spots concentrate in the sea, streams, lakes and wetlands. All these elements are found at lower elevations in the landscape. This pattern is mostly determined by the landscape topography and the locations of fracture zones. There is a relationship between fracture zones and topography, and therefore the importance of the topography for the discharge area distribution is not contradicted by the heterogeneity in the bedrock. The varieties of landscape elements which have potential for receiving

Global Warming?

ERIC Educational Resources Information Center

Eichman, Julia Christensen; Brown, Jeff A.

1994-01-01

Presents information and data on an experiment designed to test whether different atmosphere compositions are affected by light and temperature during both cooling and heating. Although flawed, the experiment should help students appreciate the difficulties that researchers face when trying to find evidence of global warming. (PR)

21 CFR 864.9205 - Blood and plasma warming device.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

21 CFR 864.9205 - Blood and plasma warming device.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

21 CFR 864.9205 - Blood and plasma warming device.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

21 CFR 864.9205 - Blood and plasma warming device.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

21 CFR 864.9205 - Blood and plasma warming device.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

Bio-inspired digital signal processing for fast radionuclide mixture identification

NASA Astrophysics Data System (ADS)

Thevenin, M.; Bichler, O.; Thiam, C.; Bobin, C.; Lourenço, V.

2015-05-01

Countries are trying to equip their public transportation infrastructure with fixed radiation portals and detectors to detect radiological threat. Current works usually focus on neutron detection, which could be useless in the case of dirty bomb that would not use fissile material. Another approach, such as gamma dose rate variation monitoring is a good indication of the presence of radionuclide. However, some legitimate products emit large quantities of natural gamma rays; environment also emits gamma rays naturally. They can lead to false detections. Moreover, such radio-activity could be used to hide a threat such as material to make a dirty bomb. Consequently, radionuclide identification is a requirement and is traditionally performed by gamma spectrometry using unique spectral signature of each radionuclide. These approaches require high-resolution detectors, sufficient integration time to get enough statistics and large computing capacities for data analysis. High-resolution detectors are fragile and costly, making them bad candidates for large scale homeland security applications. Plastic scintillator and NaI detectors fit with such applications but their resolution makes identification difficult, especially radionuclides mixes. This paper proposes an original signal processing strategy based on artificial spiking neural networks to enable fast radionuclide identification at low count rate and for mixture. It presents results obtained for different challenging mixtures of radionuclides using a NaI scintillator. Results show that a correct identification is performed with less than hundred counts and no false identification is reported, enabling quick identification of a moving threat in a public transportation. Further work will focus on using plastic scintillators.

Observational constraints on monomial warm inflation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Visinelli, Luca, E-mail: Luca.Visinelli@studio.unibo.it

Warm inflation is, as of today, one of the best motivated mechanisms for explaining an early inflationary period. In this paper, we derive and analyze the current bounds on warm inflation with a monomial potential U ∝ φ {sup p} , using the constraints from the PLANCK mission. In particular, we discuss the parameter space of the tensor-to-scalar ratio r and the potential coupling λ of the monomial warm inflation in terms of the number of e-folds. We obtain that the theoretical tensor-to-scalar ratio r ∼ 10{sup −8} is much smaller than the current observational constrain r ∼< 0.12, despitemore » a relatively large value of the field excursion Δ φ ∼ 0.1 M {sub Pl}. Warm inflation thus eludes the Lyth bound set on the tensor-to-scalar ratio by the field excursion.« less

Phosphate-Mediated Remediation of Metals and Radionuclides

DOE PAGES

Martinez, Robert J.; Beazley, Melanie J.; Sobecky, Patricia A.

2014-01-01

Worldwide industrialization activities create vast amounts of organic and inorganic waste streams that frequently result in significant soil and groundwater contamination. Metals and radionuclides are of particular concern due to their mobility and long-term persistence in aquatic and terrestrial environments. As the global population increases, the demand for safe, contaminant-free soil and groundwater will increase as will the need for effective and inexpensive remediation strategies. Remediation strategies that include physical and chemical methods (i.e., abiotic) or biological activities have been shown to impede the migration of radionuclide and metal contaminants within soil and groundwater. However, abiotic remediation methods are oftenmore » too costly owing to the quantities and volumes of soils and/or groundwater requiring treatment. The in situ sequestration of metals and radionuclides mediated by biological activities associated with microbial phosphorus metabolism is a promising and less costly addition to our existing remediation methods. This review highlights the current strategies for abiotic and microbial phosphate-mediated techniques for uranium and metal remediation.« less

Astatine-211 imaging by a Compton camera for targeted radiotherapy.

PubMed

Nagao, Yuto; Yamaguchi, Mitsutaka; Watanabe, Shigeki; Ishioka, Noriko S; Kawachi, Naoki; Watabe, Hiroshi

2018-05-24

Astatine-211 is a promising radionuclide for targeted radiotherapy. It is required to image the distribution of targeted radiotherapeutic agents in a patient's body for optimization of treatment strategies. We proposed to image 211 At with high-energy photons to overcome some problems in conventional planar or single-photon emission computed tomography imaging. We performed an imaging experiment of a point-like 211 At source using a Compton camera, and demonstrated the capability of imaging 211 At with the high-energy photons for the first time. Copyright © 2018 Elsevier Ltd. All rights reserved.

Bioremediation: a genuine technology to remediate radionuclides from the environment.

PubMed

Prakash, Dhan; Gabani, Prashant; Chandel, Anuj K; Ronen, Zeev; Singh, Om V

2013-07-01

Radionuclides in the environment are a major human and environmental health concern. Like the Chernobyl disaster of 1986, the Fukushima Daiichi nuclear disaster in 2011 is once again causing damage to the environment: a large quantity of radioactive waste is being generated and dumped into the environment, and if the general population is exposed to it, may cause serious life-threatening disorders. Bioremediation has been viewed as the ecologically responsible alternative to environmentally destructive physical remediation. Microorganisms carry endogenous genetic, biochemical and physiological properties that make them ideal agents for pollutant remediation in soil and groundwater. Attempts have been made to develop native or genetically engineered (GE) microbes for the remediation of environmental contaminants including radionuclides. Microorganism-mediated bioremediation can affect the solubility, bioavailability and mobility of radionuclides. Therefore, we aim to unveil the microbial-mediated mechanisms for biotransformation of radionuclides under various environmental conditions as developing strategies for waste management of radionuclides. A discussion follows of '-omics'-integrated genomics and proteomics technologies, which can be used to trace the genes and proteins of interest in a given microorganism towards a cell-free bioremediation strategy. © 2013 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Nonlinear regional warming with increasing CO2 concentrations

NASA Astrophysics Data System (ADS)

Good, Peter; Lowe, Jason A.; Andrews, Timothy; Wiltshire, Andrew; Chadwick, Robin; Ridley, Jeff K.; Menary, Matthew B.; Bouttes, Nathaelle; Dufresne, Jean Louis; Gregory, Jonathan M.; Schaller, Nathalie; Shiogama, Hideo

2015-02-01

When considering adaptation measures and global climate mitigation goals, stakeholders need regional-scale climate projections, including the range of plausible warming rates. To assist these stakeholders, it is important to understand whether some locations may see disproportionately high or low warming from additional forcing above targets such as 2 K (ref. ). There is a need to narrow uncertainty in this nonlinear warming, which requires understanding how climate changes as forcings increase from medium to high levels. However, quantifying and understanding regional nonlinear processes is challenging. Here we show that regional-scale warming can be strongly superlinear to successive CO2 doublings, using five different climate models. Ensemble-mean warming is superlinear over most land locations. Further, the inter-model spread tends to be amplified at higher forcing levels, as nonlinearities grow--especially when considering changes per kelvin of global warming. Regional nonlinearities in surface warming arise from nonlinearities in global-mean radiative balance, the Atlantic meridional overturning circulation, surface snow/ice cover and evapotranspiration. For robust adaptation and mitigation advice, therefore, potentially avoidable climate change (the difference between business-as-usual and mitigation scenarios) and unavoidable climate change (change under strong mitigation scenarios) may need different analysis methods.

Pacific bluefin tuna transport Fukushima-derived radionuclides from Japan to California

PubMed Central

Madigan, Daniel J.; Baumann, Zofia; Fisher, Nicholas S.

2012-01-01

The Fukushima Dai-ichi release of radionuclides into ocean waters caused significant local and global concern regarding the spread of radioactive material. We report unequivocal evidence that Pacific bluefin tuna, Thunnus orientalis, transported Fukushima-derived radionuclides across the entire North Pacific Ocean. We measured γ-emitting radionuclides in California-caught tunas and found 134Cs (4.0 ± 1.4 Bq kg−1) and elevated 137Cs (6.3 ± 1.5 Bq kg−1) in 15 Pacific bluefin tuna sampled in August 2011. We found no 134Cs and background concentrations (∼1 Bq kg−1) of 137Cs in pre-Fukushima bluefin and post-Fukushima yellowfin tunas, ruling out elevated radiocesium uptake before 2011 or in California waters post-Fukushima. These findings indicate that Pacific bluefin tuna can rapidly transport radionuclides from a point source in Japan to distant ecoregions and demonstrate the importance of migratory animals as transport vectors of radionuclides. Other large, highly migratory marine animals make extensive use of waters around Japan, and these animals may also be transport vectors of Fukushima-derived radionuclides to distant regions of the North and South Pacific Oceans. These results reveal tools to trace migration origin (using the presence of 134Cs) and potentially migration timing (using 134Cs:137Cs ratios) in highly migratory marine species in the Pacific Ocean. PMID:22645346

Reconciling controversies about the 'global warming hiatus'.

PubMed

Medhaug, Iselin; Stolpe, Martin B; Fischer, Erich M; Knutti, Reto

2017-05-03

Between about 1998 and 2012, a time that coincided with political negotiations for preventing climate change, the surface of Earth seemed hardly to warm. This phenomenon, often termed the 'global warming hiatus', caused doubt in the public mind about how well anthropogenic climate change and natural variability are understood. Here we show that apparently contradictory conclusions stem from different definitions of 'hiatus' and from different datasets. A combination of changes in forcing, uptake of heat by the oceans, natural variability and incomplete observational coverage reconciles models and data. Combined with stronger recent warming trends in newer datasets, we are now more confident than ever that human influence is dominant in long-term warming.

Forced-air warming and ultra-clean ventilation do not mix: an investigation of theatre ventilation, patient warming and joint replacement infection in orthopaedics.

PubMed

McGovern, P D; Albrecht, M; Belani, K G; Nachtsheim, C; Partington, P F; Carluke, I; Reed, M R

2011-11-01

We investigated the capacity of patient warming devices to disrupt the ultra-clean airflow system. We compared the effects of two patient warming technologies, forced-air and conductive fabric, on operating theatre ventilation during simulated hip replacement and lumbar spinal procedures using a mannequin as a patient. Infection data were reviewed to determine whether joint infection rates were associated with the type of patient warming device that was used. Neutral-buoyancy detergent bubbles were released adjacent to the mannequin's head and at floor level to assess the movement of non-sterile air into the clean airflow over the surgical site. During simulated hip replacement, bubble counts over the surgical site were greater for forced-air than for conductive fabric warming when the anaesthesia/surgery drape was laid down (p = 0.010) and at half-height (p < 0.001). For lumbar surgery, forced-air warming generated convection currents that mobilised floor air into the surgical site area. Conductive fabric warming had no such effect. A significant increase in deep joint infection, as demonstrated by an elevated infection odds ratio (3.8, p = 0.024), was identified during a period when forced-air warming was used compared to a period when conductive fabric warming was used. Air-free warming is, therefore, recommended over forced-air warming for orthopaedic procedures.

Light accelerates plant responses to warming.

PubMed

De Frenne, Pieter; Rodríguez-Sánchez, Francisco; De Schrijver, An; Coomes, David A; Hermy, Martin; Vangansbeke, Pieter; Verheyen, Kris

2015-08-17

Competition for light has profound effects on plant performance in virtually all terrestrial ecosystems. Nowhere is this more evident than in forests, where trees create environmental heterogeneity that shapes the dynamics of forest-floor communities(1-3). Observational evidence suggests that biotic responses to both anthropogenic global warming and nitrogen pollution may be attenuated by the shading effects of trees and shrubs(4-9). Here we show experimentally that tree shade is slowing down changes in below-canopy communities due to warming. We manipulated levels of photosynthetically active radiation, temperature and nitrogen, alone and in combination, in a temperate forest understorey over a 3-year period, and monitored the composition of the understorey community. Light addition, but not nitrogen enrichment, accelerated directional plant community responses to warming, increasing the dominance of warmth-preferring taxa over cold-tolerant plants (a process described as thermophilization(6,10-12)). Tall, competitive plants took greatest advantage of the combination of elevated temperature and light. Warming of the forest floor did not result in strong community thermophilization unless light was also increased. Our findings suggest that the maintenance of locally closed canopy conditions could reduce, at least temporarily, warming-induced changes in forest floor plant communities.

Consistency of the tachyon warm inflationary universe models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xiao-Min; Zhu, Jian-Yang, E-mail: zhangxm@mail.bnu.edu.cn, E-mail: zhujy@bnu.edu.cn

2014-02-01

This study concerns the consistency of the tachyon warm inflationary models. A linear stability analysis is performed to find the slow-roll conditions, characterized by the potential slow-roll (PSR) parameters, for the existence of a tachyon warm inflationary attractor in the system. The PSR parameters in the tachyon warm inflationary models are redefined. Two cases, an exponential potential and an inverse power-law potential, are studied, when the dissipative coefficient Γ = Γ{sub 0} and Γ = Γ(φ), respectively. A crucial condition is obtained for a tachyon warm inflationary model characterized by the Hubble slow-roll (HSR) parameter ε{sub H}, and the conditionmore » is extendable to some other inflationary models as well. A proper number of e-folds is obtained in both cases of the tachyon warm inflation, in contrast to existing works. It is also found that a constant dissipative coefficient (Γ = Γ{sub 0}) is usually not a suitable assumption for a warm inflationary model.« less

GHSI Emergency Radionuclide Bioassay Laboratory Network - Summary of the Second Exercise

PubMed Central

Li, Chunsheng; Bartizel, Christine; Battisti, Paolo; Böttger, Axel; Bouvier, Céline; Capote-Cuellar, Antonio; Carr, Zhanat; Hammond, Derek; Hartmann, Martina; Heikkinen, Tarja; Jones, Robert L.; Kim, Eunjoo; Ko, Raymond; Koga, Roberto; Kukhta, Boris; Mitchell, Lorna; Morhard, Ryan; Paquet, Francois; Quayle, Debora; Rulik, Petr; Sadi, Baki; Sergei, Aleksanin; Sierra, Inmaculada; de Oliveira Sousa, Wanderson; Szabó, Gyula

2017-01-01

The Global Health Security Initiative (GHSI) established a laboratory network within the GHSI community to develop collective surge capacity for radionuclide bioassay in response to a radiological or nuclear emergency as a means of enhancing response capability, health outcomes and community resilience. GHSI partners conducted an exercise in collaboration with the WHO REMPAN (Radiation Emergency Medical Preparedness and Assistance Network) and the IAEA RANET (Response and Assistance Network), to test the participating laboratories (18) for their capabilities in in vitro assay of biological samples, using a urine sample spiked with multiple high-risk radionuclides (90Sr, 106Ru, 137Cs, and 239Pu). Laboratories were required to submit their reports within 72 hours following receipt of the sample, using a pre-formatted template, on the procedures, methods and techniques used to identify and quantify the radionuclides in the sample, as well as the bioassay results with a 95% confidence interval. All of the participating laboratories identified and measured all or some of the radionuclides in the sample. However, gaps were identified in both the procedures used to assay multiple radionuclides in one sample, as well as in the methods or techniques used to assay specific radionuclides in urine. Two third of the participating laboratories had difficulties in determining all the radionuclides in the sample. Results from this exercise indicate that challenges remain with respect to ensuring that results are delivered in a timely, consistent and reliable manner to support medical interventions. Laboratories within the networks are encouraged to work together to develop and maintain collective capabilities and capacity for emergency bioassay, which is an important component of radiation emergency response. PMID:27574317

The whole-soil carbon flux in response to warming

NASA Astrophysics Data System (ADS)

Hicks Pries, Caitlin E.; Castanha, C.; Porras, R. C.; Torn, M. S.

2017-03-01

Soil organic carbon harbors three times as much carbon as Earth’s atmosphere, and its decomposition is a potentially large climate change feedback and major source of uncertainty in climate projections. The response of whole-soil profiles to warming has not been tested in situ. In a deep warming experiment in mineral soil, we found that CO2 production from all soil depths increased with 4°C warming; annual soil respiration increased by 34 to 37%. All depths responded to warming with similar temperature sensitivities, driven by decomposition of decadal-aged carbon. Whole-soil warming reveals a larger soil respiration response than many in situ experiments (most of which only warm the surface soil) and models.

Could cirrus clouds have warmed early Mars?

NASA Astrophysics Data System (ADS)

Ramirez, Ramses M.; Kasting, James F.

2017-01-01

The presence of the ancient valley networks on Mars indicates that the climate at 3.8 Ga was warm enough to allow substantial liquid water to flow on the martian surface for extended periods of time. However, the mechanism for producing this warming continues to be debated. One hypothesis is that Mars could have been kept warm by global cirrus cloud decks in a CO2sbnd H2O atmosphere containing at least 0.25 bar of CO2 (Urata and Toon, 2013). Initial warming from some other process, e.g., impacts, would be required to make this model work. Those results were generated using the CAM 3-D global climate model. Here, we use a single-column radioactive-convective climate model to further investigate the cirrus cloud warming hypothesis. Our calculations indicate that cirrus cloud decks could have produced global mean surface temperatures above freezing, but only if cirrus cloud cover approaches ∼75 - 100% and if other cloud properties (e.g., height, optical depth, particle size) are chosen favorably. However, at more realistic cirrus cloud fractions, or if cloud parameters are not optimal, cirrus clouds do not provide the necessary warming, suggesting that other greenhouse mechanisms are needed.

SOLID PHASE MICROEXTRACTION SAMPLING OF HIGH EXPLOSIVE RESIDUES IN THE PRESENCE OF RADIONUCLIDES AND RADIONUCLIDE SURROGATE METALS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duff, M; S Crump, S; Robert02 Ray, R

2007-04-13

The Federal Bureau of Investigation (FBI) Laboratory currently does not have on site facilities for handling radioactive evidentiary materials and there are no established FBI methods or procedures for decontaminating high explosive (HE) evidence while maintaining evidentiary value. One experimental method for the isolation of HE residue involves using solid phase microextraction or SPME fibers to remove residue of interest. Due to their high affinity for organics, SPME fibers should have little affinity for most metals. However, no studies have measured the affinity of radionuclides for SPME fibers. The focus of this research was to examine the affinity of dissolvedmore » radionuclide ({sup 239/240}Pu, {sup 238}U, {sup 237}Np, {sup 85}Sr, {sup 133}Ba, {sup 137}Cs, {sup 60}Co and {sup 226}Ra) and stable radionuclide surrogate metals (Sr, Co, Ir, Re, Ni, Ba, Cs, Nb, Zr, Ru, and Nd) for SPME fibers at the exposure conditions that favor the uptake of HE residues. Our results from radiochemical and mass spectrometric analyses indicate these metals have little measurable affinity for these SPME fibers during conditions that are conducive to HE residue uptake with subsequent analysis by liquid or gas phase chromatography with mass spectrometric detection.« less

Cosmogenic radionuclides

NASA Astrophysics Data System (ADS)

Cosmic rays interact with the earth's atmosphere and surface to produce the “cosmogenic” nuclides. In many instances the radioactive ones are readily distinguished from the anthropogenic and meteoritic backgrounds. Measurements of these cosmogenic radionuclides (RCN) can contribute to the solution of a variety of geophysical problems [Lai and Peters, 1967]. Recent progress in this area was discussed at a symposium entitled Application of Cosmic-Ray-Produced Nuclides in Geophysics held May 30, 1983, at the AGU Spring Meeting in Baltimore (see Eos, May 3, 1983, pp. 282-284, for the abstracts). We summarize here the symposium presentations.

Effects of experimental throughfall reduction and soil warming on fine root biomass and its decomposition in a warm temperate oak forest.

PubMed

Liu, Yanchun; Liu, Shirong; Wan, Shiqiang; Wang, Jingxin; Wang, Hui; Liu, Kuan

2017-01-01

Fine root dynamics play a critical role in regulating carbon (C) cycling in terrestrial ecosystems. Examining responses of fine root biomass and its decomposition to altered precipitation pattern and climate warming is crucial to understand terrestrial C dynamics and its feedback to climate change. Fine root biomass and its decomposition rate were investigated in a warm temperate oak forest through a field manipulation experiment with throughfall reduction and soil warming conducted. Throughfall reduction significantly interacted with soil warming in affecting fine root biomass and its decomposition. Throughfall reduction substantially increased fine root biomass and its decomposition in unheated plots, but negative effects occurred in warmed plots. Soil warming significantly enhanced fine root biomass and its decomposition under ambient precipitation, but the opposite effects exhibited under throughfall reduction. Different responses in fine root biomass among different treatments could be largely attributed to soil total nitrogen (N), while fine root decomposition rate was more depended on microbial biomass C and N. Our observations indicate that decreased precipitation may offset the positive effect of soil warming on fine root biomass and decomposition. Copyright © 2016 Elsevier B.V. All rights reserved.

Change of ENSO characteristics in response to global warming

NASA Astrophysics Data System (ADS)

Sun, X.; Xia, Y.; Yan, Y.; Feng, W.; Huang, F.; Yang, X. Q.

2017-12-01

By using datasets of HadISST monthly SST from 1895 to 2014 and 600-year simulations of two CESM model experiments with/without doubling of CO2 concentration, ENSO characteristics are compared pre- and post- global warming. The main results are as follows. Due to global warming, the maximum climatological SST warming occurs in the tropical western Pacific (La Niña-like background warming) and the tropical eastern Pacific (El Niño-like background warming) for observations and model, respectively, resulting in opposite zonal SST gradient anomalies in the tropical Pacific. The La Niña-like background warming induces intense surface divergence in the tropical central Pacific, which enhances the easterly trade winds in the tropical central-western Pacific and shifts the strongest ocean-atmosphere coupling westward, correspondingly. On the contrary, the El Niño-like background warming causes westerly winds in the whole tropical Pacific and moves the strongest ocean-atmosphere coupling eastward. Under the La Niña-like background warming, ENSO tends to develop and mature in the tropical central Pacific, because the background easterly wind anomaly weakens the ENSO-induced westerly wind anomaly in the tropical western Pacific, leading to the so-called "Central Pacific ENSO (CP ENSO)". However, the so-called "Eastern Pacific ENSO (EP ENSO)" is likely formed due to increased westerly wind anomaly by the El Niño-like background warming. ENSO lifetime is significantly extended under both the El Niño-like and the La Niña-like background warmings, and especially, it can be prolonged by up to 3 months in the situation of El Niño-like background warming. The prolonged El Nino lifetime mainly applies to extreme El Niño events, which is caused by earlier outbreak of the westerly wind bursts, shallower climatological thermocline depth and weaker "discharge" rate of the ENSO warm signal in response to global warming. Results from both observations and the model also show that

Microbial stabilization and mass reduction of wastes containing radionuclides and toxic metals

DOEpatents

Francis, A.J.; Dodge, C.J.; Gillow, J.B.

1991-09-10

A process is provided to treat wastes containing radionuclides and toxic metals with Clostridium sp. BFGl to release a large fraction of the waste solids into solution and convert the radionuclides and toxic metals to a more concentrated and stable form with concurrent volume and mass reduction. The radionuclides and toxic metals being in a more stable form are available for recovery, recycling and disposal. 18 figures.

Microbial stabilization and mass reduction of wastes containing radionuclides and toxic metals

DOEpatents

Francis, Arokiasamy J.; Dodge, Cleveland J.; Gillow, Jeffrey B.

1991-01-01

A process is provided to treat wastes containing radionuclides and toxic metals with Clostridium sp. BFGl to release a large fraction of the waste solids into solutin and convert the radionuclides and toxic metals to a more concentrated and stable form with concurrent volume and mass reduction. The radionuclides and toxic metals being in a more stable form are available for recovery, recycling and disposal.

Abrupt warming of the Red Sea

NASA Astrophysics Data System (ADS)

Raitsos, D. E.; Hoteit, I.; Prihartato, P. K.; Chronis, T.; Triantafyllou, G.; Abualnaja, Y.

2011-07-01

Coral reef ecosystems, often referred to as “marine rainforests,” concentrate the most diverse life in the oceans. Red Sea reef dwellers are adapted in a very warm environment, fact that makes them vulnerable to further and rapid warming. The detection and understanding of abrupt temperature changes is an important task, as ecosystems have more chances to adapt in a slowly rather than in a rapid changing environment. Using satellite derived sea surface and ground based air temperatures, it is shown that the Red Sea is going through an intense warming initiated in the mid-90s, with evidence for an abrupt increase after 1994 (0.7°C difference pre and post the shift). The air temperature is found to be a key parameter that influences the Red Sea marine temperature. The comparisons with Northern Hemisphere temperatures revealed that the observed warming is part of global climate change trends. The hitherto results also raise additional questions regarding other broader climatic impacts over the area.

The use of radiocobalt as a label improves imaging of EGFR using DOTA-conjugated Affibody molecule.

PubMed

Garousi, Javad; Andersson, Ken G; Dam, Johan H; Olsen, Birgitte B; Mitran, Bogdan; Orlova, Anna; Buijs, Jos; Ståhl, Stefan; Löfblom, John; Thisgaard, Helge; Tolmachev, Vladimir

2017-07-20

Several anti-cancer therapies target the epidermal growth factor receptor (EGFR). Radionuclide imaging of EGFR expression in tumours may aid in selection of optimal cancer therapy. The 111 In-labelled DOTA-conjugated Z EGFR:2377 Affibody molecule was successfully used for imaging of EGFR-expressing xenografts in mice. An optimal combination of radionuclide, chelator and targeting protein may further improve the contrast of radionuclide imaging. The aim of this study was to evaluate the targeting properties of radiocobalt-labelled DOTA-Z EGFR:2377 . DOTA-Z EGFR:2377 was labelled with 57 Co (T 1/2  = 271.8 d), 55 Co (T 1/2  = 17.5 h), and, for comparison, with the positron-emitting radionuclide 68 Ga (T 1/2  = 67.6 min) with preserved specificity of binding to EGFR-expressing A431 cells. The long-lived cobalt radioisotope 57 Co was used in animal studies. Both 57 Co-DOTA-Z EGFR:2377 and 68 Ga-DOTA-Z EGFR:2377 demonstrated EGFR-specific accumulation in A431 xenografts and EGFR-expressing tissues in mice. Tumour-to-organ ratios for the radiocobalt-labelled DOTA-Z EGFR:2377 were significantly higher than for the gallium-labelled counterpart already at 3 h after injection. Importantly, 57 Co-DOTA-Z EGFR:2377 demonstrated a tumour-to-liver ratio of 3, which is 7-fold higher than the tumour-to-liver ratio for 68 Ga-DOTA-Z EGFR:2377 . The results of this study suggest that the positron-emitting cobalt isotope 55 Co would be an optimal label for DOTA-Z EGFR:2377 and further development should concentrate on this radionuclide as a label.

Temporal Fourier analysis applied to equilibrium radionuclide cineangiography. Importance in the study of global and regional left ventricular wall motion.

PubMed

Cardot, J C; Berthout, P; Verdenet, J; Bidet, A; Faivre, R; Bassand, J P; Bidet, R; Maurat, J P

1982-01-01

Regional and global left ventricular wall motion was assessed in 120 patients using radionuclide cineangiography (RCA) and contrast angiography. Functional imaging procedures based on a temporal Fourier analysis of dynamic image sequences were applied to the study of cardiac contractility. Two images were constructed by taking the phase and amplitude values of the first harmonic in the Fourier transform for each pixel. These two images aided in determining the perimeter of the left ventricle to calculate the global ejection fraction. Regional left ventricular wall motion was studied by analyzing the phase value and by examining the distribution histogram of these values. The accuracy of global ejection fraction calculation was improved by the Fourier technique. This technique increased the sensitivity of RCA for determining segmental abnormalities especially in the left anterior oblique view (LAO).

NorTropical Warm Pool variability and its effects on the climate of Colombia

NASA Astrophysics Data System (ADS)

Ricaurte Villota, Constanza; Romero-Rodriguez, Deisy; Coca-Domínguez, Oswaldo

2015-04-01

Much has been said about the effects of El Niño Southern Oscillation (ENSO) on oceanographic and climatic conditions in Colombia, but little is known about the influence of the Atlantic Warm Pool (AWP), which includes the gulf of Mexico, the Caribbean and the western tropical North Atlantic. The AWP has been identified by some authors as an area that influences the Earth's climate, associated with anomalous summer rainfall and hurricane activity in the Atlantic. The aim of this study was to understand the variation in the AWP and its effects on the climate of Colombia. An annual average of sea surface temperature (SST) was obtained from the composition of monthly images of the Spectroradiometer Moderate Resolution Imaging Spectroradiometer (MODIS), with resolution of 4 km, for one area that comprises the marine territory of Colombia, Panama, Costa Rica both the Pacific and the Caribbean, and parts of the Caribbean coast of Nicaragua, for the period between 2007 and 2013. The results suggest that warm pool is not restricted to the Caribbean, but it also covers a strip Pacific bordering Central America and the northern part of the Colombian coast, so it should be called the Nor-Tropical Warm pool (NTWP). Within the NTWP higher SST correspond to a marine area extending about 1 degree north and south of Central and out of the Colombian Caribbean coast. The NTWP also showed large interannual variability, with the years 2008 and 2009 with lower SST in average, while 2010, 2011 and 2013 years with warmer conditions, matching with greater precipitation. It was also noted that during warmer conditions (high amplitude NTWP) the cold tongue from the south Pacific has less penetration on Colombian coast. Finally, the results suggest a strong influence of NTWP in climatic conditions in Colombia.

ASTER Images Merapi Continuing Eruption

NASA Image and Video Library

2010-11-18

This thermal infrared image from NASA Terra spacecraft of Merapi continuing eruption has been processed to reveal the dominant presence of volcanic ash in the eruption plume and clouds, displayed in dark red. The warm volcanic flow appears bright.

Population risk perceptions of global warming in Australia.

PubMed

Agho, Kingsley; Stevens, Garry; Taylor, Mel; Barr, Margo; Raphael, Beverley

2010-11-01

According to the World Health Organisation (WHO), global warming has the potential to dramatically disrupt some of life's essential requirements for health, water, air and food. Understanding how Australians perceive the risk of global warming is essential for climate change policy and planning. The aim of this study was to determine the prevalence of, and socio-demographic factors associated with, high levels of perceived likelihood that global warming would worsen, concern for self and family and reported behaviour changes. A module of questions on global warming was incorporated into the New South Wales Population Health Survey in the second quarter of 2007. This Computer Assisted Telephone Interview (CATI) was completed by a representative sample of 2004 adults. The weighted sample was comparable to the Australian population. Bivariate and multivariate statistical analyses were conducted to examine the socio-demographic and general health factors. Overall 62.1% perceived that global warming was likely to worsen; 56.3% were very or extremely concerned that they or their family would be directly affected by global warming; and 77.6% stated that they had made some level of change to the way they lived their lives, because of the possibility of global warming. After controlling for confounding factors, multivariate analyses revealed that those with high levels of psychological distress were 2.17 (Adjusted Odds Ratio (AOR)=2.17; CI: 1.16-4.03; P=0.015) times more likely to be concerned about global warming than those with low psychological distress levels. Those with a University degree or equivalent and those who lived in urban areas were significantly more likely to think that global warming would worsen compared to those without a University degree or equivalent and those who lived in the rural areas. Females were significantly (AOR=1.69; CI: 1.23-2.33; P=0.001) more likely to report they had made changes to the way they lived their lives due to the risk of

Cosmogenic radionuclides as a synchronisation tool - present status

NASA Astrophysics Data System (ADS)

Muscheler, Raimund; Adolphi, Florian; Mekhaldi, Florian; Mellström, Anette; Svensson, Anders; Aldahan, Ala; Possnert, Göran

2014-05-01

Changes in the flux of galactic cosmic rays into Earth's atmosphere produce variations in the production rates of cosmogenic radionuclides. The resulting globally synchronous signal in cosmogenic radionuclide records can be used to compare time scales and synchronise climate records. The most prominent example is the 14C wiggle match dating approach where variations in the atmospheric 14C concentration are used to match climate records and the tree-ring based part of the 14C calibration record. This approach can be extended to other cosmogenic radionuclide records such as 10Be time series provided that the different geochemical behaviour of 10Be and 14C is taken into account. Here we will present some recent results that illustrate the potential of using cosmogenic radionuclide records for comparing and synchronising different time scales. The focus will be on the last 50000 years where we will show examples how geomagnetic field, solar activity and unusual short-term cosmic ray changes can be used for comparing ice core, tree ring and sediment time scales. We will discuss some unexpected offsets between Greenland ice core and 14C time scale and we will examine how far back in time solar induced 10Be and 14C variations presently can be used to reliably synchronise ice core and 14C time scales.

Radiation, radionuclides and bacteria: An in-perspective review.

PubMed

Shukla, Arpit; Parmar, Paritosh; Saraf, Meenu

2017-12-01

There has been a significant surge in consumption of radionuclides for various academic and commercial purposes. Correspondingly, there has been a considerable amount of generation of radioactive waste. Bacteria and archaea, being earliest inhabitants on earth serve as model microorganisms on earth. These microbes have consistently proven their mettle by surviving extreme environments, even extreme ionizing radiations. Their ability to accept and undergo stable genetic mutations have led to development of recombinant mutants that are been exploited for remediation of various pollutants such as; heavy metals, hydrocarbons and even radioactive waste (radwaste). Thus, microbes have repeatedly presented themselves to be prime candidates suitable for remediation of radwaste. It is interesting to study the behind-the-scenes interactions these microbes possess when observed in presence of radionuclides. The emphasis is on the indigenous bacteria isolated from radionuclide containing environments as well as the five fundamental interaction mechanisms that have been studied extensively, namely; bioaccumulation, biotransformation, biosorption, biosolubilisation and bioprecipitation. Application of microbes exhibiting such mechanisms in remediation of radioactive waste depends largely on the individual capability of the species. Challenges pertaining to its potential bioremediation activity is also been briefly discussed. This review provides an insight into the various mechanisms bacteria uses to tolerate, survive and carry out processes that could potentially lead the eco-friendly approach for removal of radionuclides. Copyright © 2017 Elsevier Ltd. All rights reserved.

Radionuclide thyroid imaging in the newborn with suspected hypothyroidism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoosufani, Z.; Karimeddini, M.K.; Spencer, R.P.

1985-05-01

The authors reviewed their experience with thyroid imaging in newborns with suspected congenital hypothyroidism. The infants were selected through a hypothyroidism screening program. There were 19 infants (14 females, 5 males) from 2 to 8 weeks of age with a blood T4 <6 ..mu..g/dl. Thyroid imaging was performed with either IV or IM injection of 0.5 to 1 mCi of Tc 99m pertechnetate using a gamma camera with a pinhole collimator. Salivary glands and stomach were also imaged for assessing the presence of the transport system. In 6 infants (32%) no thyroid tissue was visualized (thyroid hypoplasia). Four infants (21%)more » showed ectopic thyroid tissue in the lingual or sublingual area. Two infants (10%) had evidence of goiter. The remaining 7 infants (37%) had normal appearing glands in size and position. TSH values were markedly elevated (> 100 ..mu mu../ml) in all 10 patients with hypoplastic or ectopic thyroid. Two patients were subsequently found to have normal thyroid function (one with TBG deficiency and one with transient hypothyroidism). Thyroidal as well as salivary gland trapping of the radiotracer in these two infants was clearly less than that of adults suggesting immaturity of the transport/trapping mechanism. All 4 patients with ectopic thyroid had markedly increased uptake of the radiotracer. All other patients with elevated TSH levels had increased uptake of the radiotracer as compared to the normals. They conclude that thyroid scanning is an important tool in delineating the etiology of congenital hypothyroidism.« less

Phantom feet on digital radionuclide images and other scary computer tales

DOE Office of Scientific and Technical Information (OSTI.GOV)

Freitas, J.E.; Dworkin, H.J.; Dees, S.M.

1989-09-01

Malfunction of a computer-assisted digital gamma camera is reported. Despite what appeared to be adequate acceptance testing, an error in the system gave rise to switching of images and identification text. A suggestion is made for using a hot marker, which would avoid the potential error of misinterpretation of patient images.

Soil warming, carbon–nitrogen interactions, and forest carbon budgets

PubMed Central

Melillo, Jerry M.; Butler, Sarah; Johnson, Jennifer; Mohan, Jacqueline; Steudler, Paul; Lux, Heidi; Burrows, Elizabeth; Bowles, Francis; Smith, Rose; Scott, Lindsay; Vario, Chelsea; Hill, Troy; Burton, Andrew; Zhou, Yu-Mei; Tang, Jim

2011-01-01

Soil warming has the potential to alter both soil and plant processes that affect carbon storage in forest ecosystems. We have quantified these effects in a large, long-term (7-y) soil-warming study in a deciduous forest in New England. Soil warming has resulted in carbon losses from the soil and stimulated carbon gains in the woody tissue of trees. The warming-enhanced decay of soil organic matter also released enough additional inorganic nitrogen into the soil solution to support the observed increases in plant carbon storage. Although soil warming has resulted in a cumulative net loss of carbon from a New England forest relative to a control area over the 7-y study, the annual net losses generally decreased over time as plant carbon storage increased. In the seventh year, warming-induced soil carbon losses were almost totally compensated for by plant carbon gains in response to warming. We attribute the plant gains primarily to warming-induced increases in nitrogen availability. This study underscores the importance of incorporating carbon–nitrogen interactions in atmosphere–ocean–land earth system models to accurately simulate land feedbacks to the climate system. PMID:21606374

Estimation of aquifer radionuclide concentrations by postprocessing of conservative tracer model results

NASA Astrophysics Data System (ADS)

Gedeon, M.; Vandersteen, K.; Rogiers, B.

2012-04-01

Radionuclide concentrations in aquifers represent an important indicator in estimating the impact of a planned surface disposal for low and medium level short-lived radioactive waste in Belgium, developed by the Belgian Agency for Radioactive Waste and Enriched Fissile Materials (ONDRAF/NIRAS), who also coordinates and leads the corresponding research. Estimating aquifer concentrations for individual radionuclides represents a computational challenge because (a) different retardation values are applied to different hydrogeologic units and (b) sequential decay reactions with radionuclides of various sorption characteristics cause long computational times until a steady-state is reached. The presented work proposes a methodology reducing substantially the computational effort by postprocessing the results of a prior non-reactive tracer simulation. These advective transport results represent the steady-state concentration - source flux ratio and the break-through time at each modelling cell. These two variables are further used to estimate the individual radionuclide concentrations by (a) scaling the steady-state concentrations to the source fluxes of individual radionuclides; (b) applying the radioactive decay and ingrowth in a decay chain; (c) scaling the travel time by the retardation factor and (d) applying linear sorption. While all steps except (b) require solving simple linear equations, applying ingrowth of individual radionuclides in decay chains requires solving the differential Bateman equation. This equation needs to be solved once for a unit radionuclide activity at all arrival times found in the numerical grid. The ratios between the parent nuclide activity and the progeny activities are then used in the postprocessing. Results are presented for discrete points and examples of radioactive plume maps are given. These results compare well to the results achieved using a full numerical simulation including the respective chemical reaction processes

Methane Cycling in a Warming Wetland

NASA Astrophysics Data System (ADS)

Noyce, G. L.; Megonigal, P.; Rich, R.; Kirwan, M. L.; Herbert, E. R.

2017-12-01

Coastal wetlands are global hotspots of carbon (C) storage, but the future of these systems is uncertain. In June 2016, we initiated an in-situ, active, whole-ecosystem warming experiment in the Smithsonian's Global Change Research Wetland to quantify how warming and elevated CO2 affect the stability of coastal wetland soil C pools and contemporary rates of C sequestration. Transects are located in two plant communities, dominated by C3 sedges or C4 grasses. The experiment has a gradient design with air and soil warming treatments ranging from ambient to +5.1 °C and heated plots consistently maintain their target temperature year-round. In April 2017, an elevated CO2 treatment was crossed with temperature in the C3community. Ongoing measurements include soil elevation, C fluxes, porewater chemistry and redox potential, and above- and below-ground growth and biomass. In both years, warming increased methane (CH4) emissions (measured at 3-4 week intervals) from spring through fall at the C3 site, but had little effect on emissions from the C4 site. Winter (Dec-Mar) emissions showed no treatment effect. Stable isotope analysis of dissolved CH4 and DIC also indicated that warming had differing effects on CH4 pathways in the two vegetation communities. To better understand temperature effects on rates of CH4 production and oxidation, 1 m soil cores were collected from control areas of the marsh in summer 2017 and incubated at temperatures ranging from 4 °C to 35 °C. Warming increased CH4 production and oxidation rates in surface samples and oxidation rates in the rooting zone samples from both sites, but temperature responses in deep (1 m) soil samples were minimal. In the surface and rooting zone samples, production rates were also consistently higher in C3 soils compared to C4 soils, but, contrary to our expectations, the temperature response was stronger in the C4 soils. However, oxidation in C3 rooting zone samples did have a strong temperature response. The

RADIONUCLIDE INVENTORY AND DISTRIBUTION: FOURMILE BRANCH, PEN BRANCH, AND STEEL CREEK IOUS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hiergesell, R.; Phifer, M.

2014-04-29

As a condition to the Department of Energy (DOE) Low Level Waste Disposal Federal Facility Review Group (LFRG) review team approving the Savannah River Site (SRS) Composite Analysis (CA), SRS agreed to follow up on a secondary issue, which consisted of the consolidation of several observations that the team concluded, when evaluated collectively, could potentially impact the integration of the CA results. This report addresses secondary issue observations 4 and 21, which identify the need to improve the CA sensitivity and uncertainty analysis specifically by improving the CA inventory and the estimate of its uncertainty. The purpose of the workmore » described herein was to be responsive to these secondary issue observations by re-examining the radionuclide inventories of the Integrator Operable Units (IOUs), as documented in ERD 2001 and Hiergesell, et. al. 2008. The LFRG concern has been partially addressed already for the Lower Three Runs (LTR) IOU (Hiergesell and Phifer, 2012). The work described in this investigation is a continuation of the effort to address the LFRG concerns by re-examining the radionuclide inventories associated with Fourmile Branch (FMB) IOU, Pen Branch (PB) IOU and Steel Creek (SC) IOU. The overall approach to computing radionuclide inventories for each of the IOUs involved the following components: • Defining contaminated reaches of sediments along the IOU waterways • Identifying separate segments within each IOU waterway to evaluate individually • Computing the volume and mass of contaminated soil associated with each segment, or “compartment” • Obtaining the available and appropriate Sediment and Sediment/Soil analytical results associated with each IOU • Standardizing all radionuclide activity by decay-correcting all sample analytical results from sample date to the current point in time, • Computing representative concentrations for all radionuclides associated with each compartment in each of the IOUs • Computing

Direct Imaging of Radionuclide-Produced Electrons and Positrons with an Ultrathin Phosphor

PubMed Central

Chen, Liying; Gobar, Lisa S.; Knowles, Negar G.; Liu, Zhonglin; Gmitro, Arthur F.; Barrett, Harrison H.

2008-01-01

Current electron detectors are either unable to image in vivo or lack sufficient spatial resolution because of electron scattering in thick detector materials. This study was aimed at developing a sensitive high-resolution system capable of detecting electron-emitting isotopes in vivo. Methods The system uses a lens-coupled charge-coupled-device camera to capture the scintillation light excited by an electron-emitting object near an ultrathin phosphor. The spatial resolution and sensitivity of the system were measured with a 3.7-kBq 90Y/90Sr β-source and a 70-µm resin bead labeled with 99mTc. Finally, we imaged the 99mTc-pertechnetate concentration in the mandibular gland of a mouse in vivo. Results Useful images were obtained with only a few hundred emitted β particles from the 90Y/90Sr source or conversion electrons from the 99mTc bead source. The in vivo image showed a clear profile of the mandibular gland and many fine details with exposures of as low as 30 s. All measurements were consistent with a spatial resolution of about 50 µm, corresponding to 2.5 detector pixels with the current camera. Conclusion Our new electron-imaging system can image electron-emitting isotope distributions at high resolution and sensitivity. The system is useful for in vivo imaging of small animals and small, exposed regions on humans. The ability to image β particles, positrons, and conversion electrons makes the system applicable to most isotopes. PMID:18552136

Precompetition warm-up in elite and subelite rhythmic gymnastics.

PubMed

Guidetti, Laura; Di Cagno, Alessandra; Gallotta, Maria Chiara; Battaglia, Claudia; Piazza, Marina; Baldari, Carlo

2009-09-01

The aim of this study was to investigate which precompetition warm-up methodologies resulted in the best overall performance in rhythmic gymnastics. The coaches of national and international clubs (60 elite and 90 subelite) were interviewed. The relationship between sport performance and precompetition warm-up routines was examined. A total of 49% of the coaches interviewed spent more than 1 hour to prepare their athletes for the competition, including 45 minutes dedicated to warm-up exercises. In spite of previous studies' suggestions, the time between the end of warm-up and the beginning of competition was more than 5 minutes for 68% of those interviewed. A slow run was the activity of choice used to begin the warm-up (96%). Significant differences between elite and subelite gymnasts were found concerning the total duration of warm-up, duration of slow running, utilization of rhythmic steps and leaps during the warm-up, the use of dynamic flexibility exercises, competition performances repetition (p < 0.01), and utilization of imagery (p < 0.05). A precompetition warm-up in rhythmic gymnastics would include static stretching exercises at least 60 minutes prior to the competition starting time and the active stretching exercises alternated with analytic muscle strengthening aimed at increasing muscle temperature. Rhythmic gymnastics coaches at all levels can use this data as a review of precompetition warm-up practices and a possible source of new ideas.

Global warming without global mean precipitation increase?

PubMed Central

Salzmann, Marc

2016-01-01

Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K−1 decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge. PMID:27386558

Global warming without global mean precipitation increase?

PubMed

Salzmann, Marc

2016-06-01

Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K(-1) decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge.

Turkish Students' Ideas about Global Warming

ERIC Educational Resources Information Center

Kilinc, Ahmet; Stanisstreet, Martin; Boyes, Edward

2008-01-01

A questionnaire was used to explore the prevalence of ideas about global warming in Year 10 (age 15-16 years) school students in Turkey. The frequencies of individual scientific ideas and misconceptions about the causes, consequences and "cures" of global warming were identified. In addition, several general findings emerged from this…

GHSI EMERGENCY RADIONUCLIDE BIOASSAY LABORATORY NETWORK - SUMMARY OF THE SECOND EXERCISE.

PubMed

Li, Chunsheng; Bartizel, Christine; Battisti, Paolo; Böttger, Axel; Bouvier, Céline; Capote-Cuellar, Antonio; Carr, Zhanat; Hammond, Derek; Hartmann, Martina; Heikkinen, Tarja; Jones, Robert L; Kim, Eunjoo; Ko, Raymond; Koga, Roberto; Kukhta, Boris; Mitchell, Lorna; Morhard, Ryan; Paquet, Francois; Quayle, Debora; Rulik, Petr; Sadi, Baki; Sergei, Aleksanin; Sierra, Inmaculada; de Oliveira Sousa, Wanderson; Szab, Gyula

2017-05-01

The Global Health Security Initiative (GHSI) established a laboratory network within the GHSI community to develop collective surge capacity for radionuclide bioassay in response to a radiological or nuclear emergency as a means of enhancing response capability, health outcomes and community resilience. GHSI partners conducted an exercise in collaboration with the WHO Radiation Emergency Medical Preparedness and Assistance Network and the IAEA Response and Assistance Network, to test the participating laboratories (18) for their capabilities in in vitro assay of biological samples, using a urine sample spiked with multiple high-risk radionuclides (90Sr, 106Ru, 137Cs, and 239Pu). Laboratories were required to submit their reports within 72 h following receipt of the sample, using a pre-formatted template, on the procedures, methods and techniques used to identify and quantify the radionuclides in the sample, as well as the bioassay results with a 95% confidence interval. All of the participating laboratories identified and measured all or some of the radionuclides in the sample. However, gaps were identified in both the procedures used to assay multiple radionuclides in one sample, as well as in the methods or techniques used to assay specific radionuclides in urine. Two-third of the participating laboratories had difficulties in determining all the radionuclides in the sample. Results from this exercise indicate that challenges remain with respect to ensuring that results are delivered in a timely, consistent and reliable manner to support medical interventions. Laboratories within the networks are encouraged to work together to develop and maintain collective capabilities and capacity for emergency bioassay, which is an important component of radiation emergency response. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Exploration of warm-up period in conceptual hydrological modelling

NASA Astrophysics Data System (ADS)

Kim, Kue Bum; Kwon, Hyun-Han; Han, Dawei

2018-01-01

One of the important issues in hydrological modelling is to specify the initial conditions of the catchment since it has a major impact on the response of the model. Although this issue should be a high priority among modelers, it has remained unaddressed by the community. The typical suggested warm-up period for the hydrological models has ranged from one to several years, which may lead to an underuse of data. The model warm-up is an adjustment process for the model to reach an 'optimal' state, where internal stores (e.g., soil moisture) move from the estimated initial condition to an 'optimal' state. This study explores the warm-up period of two conceptual hydrological models, HYMOD and IHACRES, in a southwestern England catchment. A series of hydrologic simulations were performed for different initial soil moisture conditions and different rainfall amounts to evaluate the sensitivity of the warm-up period. Evaluation of the results indicates that both initial wetness and rainfall amount affect the time required for model warm up, although it depends on the structure of the hydrological model. Approximately one and a half months are required for the model to warm up in HYMOD for our study catchment and climatic conditions. In addition, it requires less time to warm up under wetter initial conditions (i.e., saturated initial conditions). On the other hand, approximately six months is required for warm-up in IHACRES, and the wet or dry initial conditions have little effect on the warm-up period. Instead, the initial values that are close to the optimal value result in less warm-up time. These findings have implications for hydrologic model development, specifically in determining soil moisture initial conditions and warm-up periods to make full use of the available data, which is very important for catchments with short hydrological records.

Warm-Up Strategies for Sport and Exercise: Mechanisms and Applications.

PubMed

McGowan, Courtney J; Pyne, David B; Thompson, Kevin G; Rattray, Ben

2015-11-01

It is widely accepted that warming-up prior to exercise is vital for the attainment of optimum performance. Both passive and active warm-up can evoke temperature, metabolic, neural and psychology-related effects, including increased anaerobic metabolism, elevated oxygen uptake kinetics and post-activation potentiation. Passive warm-up can increase body temperature without depleting energy substrate stores, as occurs during the physical activity associated with active warm-up. While the use of passive warm-up alone is not commonplace, the idea of utilizing passive warming techniques to maintain elevated core and muscle temperature throughout the transition phase (the period between completion of the warm-up and the start of the event) is gaining in popularity. Active warm-up induces greater metabolic changes, leading to increased preparedness for a subsequent exercise task. Until recently, only modest scientific evidence was available supporting the effectiveness of pre-competition warm-ups, with early studies often containing relatively few participants and focusing mostly on physiological rather than performance-related changes. External issues faced by athletes pre-competition, including access to equipment and the length of the transition/marshalling phase, have also frequently been overlooked. Consequently, warm-up strategies have continued to develop largely on a trial-and-error basis, utilizing coach and athlete experiences rather than scientific evidence. However, over the past decade or so, new research has emerged, providing greater insight into how and why warm-up influences subsequent performance. This review identifies potential physiological mechanisms underpinning warm-ups and how they can affect subsequent exercise performance, and provides recommendations for warm-up strategy design for specific individual and team sports.

ITE CHARACTERIZATION TO SUPPORT CONCEPTUAL MODEL DEVELOPMENT FOR SUBSURFACE RADIONUCLIDE TRANSPORT

EPA Science Inventory

Remediation of radionuclide contaminants in ground water often begins with the development of conceptual and analytical models that guide our understanding of the processes controlling radionuclide transport. The reliability of these models is often predicated on the collection o...

Warm-up before laparoscopic surgery is not essential.

PubMed

Weston, Maree K; Stephens, Jacqueline H; Schafer, Amy; Hewett, Peter J

2014-03-01

Several recent studies have suggested that warming up prior to surgery may improve surgical performance. The purpose of this study was to investigate whether warming up prior to laparoscopic surgery improves surgical performance or reduces surgery duration. Between August 2011 and January 2012, a randomized controlled trial was conducted to compare two warm-up modalities to no warm-up. The study was conducted at a single site, with nine surgeons performing 72 laparoscopic cholecystectomies and 37 laparoscopic appendicectomies. Prior to surgery, surgeons were randomized to either laparoscopic trainer box warm-up, PlayStation 2 warm-up or no warm-up. The activity was performed within 30 min of surgery commencing. Patients provided informed consent for the surgery to be digitally recorded. Digital videodiscs (DVDs) were reviewed by an independent and blinded assessor. Data were collected on duration of surgery, level of training and perceived surgical difficulty. Surgical performance was graded using a validated scoring system. From the 109 operations performed, there were 75 usable DVDs. Overall, there were no statistical differences in the demographics of patients and surgeons in the three treatment groups, nor in the subset that had useable DVDs. There were no statistical differences in the duration of surgery or surgeon's perceived surgical difficulty. There was no statistical difference in surgical performance. This study suggests that warm-up prior to laparoscopic cholecystectomy or appendicectomy is not essential, acknowledging that there are several study limitations that preclude definitive conclusion. © 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.

Anthropogenic warming has increased drought risk in California.

PubMed

Diffenbaugh, Noah S; Swain, Daniel L; Touma, Danielle

2015-03-31

California is currently in the midst of a record-setting drought. The drought began in 2012 and now includes the lowest calendar-year and 12-mo precipitation, the highest annual temperature, and the most extreme drought indicators on record. The extremely warm and dry conditions have led to acute water shortages, groundwater overdraft, critically low streamflow, and enhanced wildfire risk. Analyzing historical climate observations from California, we find that precipitation deficits in California were more than twice as likely to yield drought years if they occurred when conditions were warm. We find that although there has not been a substantial change in the probability of either negative or moderately negative precipitation anomalies in recent decades, the occurrence of drought years has been greater in the past two decades than in the preceding century. In addition, the probability that precipitation deficits co-occur with warm conditions and the probability that precipitation deficits produce drought have both increased. Climate model experiments with and without anthropogenic forcings reveal that human activities have increased the probability that dry precipitation years are also warm. Further, a large ensemble of climate model realizations reveals that additional global warming over the next few decades is very likely to create ∼ 100% probability that any annual-scale dry period is also extremely warm. We therefore conclude that anthropogenic warming is increasing the probability of co-occurring warm-dry conditions like those that have created the acute human and ecosystem impacts associated with the "exceptional" 2012-2014 drought in California.

Experimental whole-stream warming alters community size structure.

PubMed

Nelson, Daniel; Benstead, Jonathan P; Huryn, Alexander D; Cross, Wyatt F; Hood, James M; Johnson, Philip W; Junker, James R; Gíslason, Gísli M; Ólafsson, Jón S

2017-07-01

How ecological communities respond to predicted increases in temperature will determine the extent to which Earth's biodiversity and ecosystem functioning can be maintained into a warmer future. Warming is predicted to alter the structure of natural communities, but robust tests of such predictions require appropriate large-scale manipulations of intact, natural habitat that is open to dispersal processes via exchange with regional species pools. Here, we report results of a two-year whole-stream warming experiment that shifted invertebrate assemblage structure via unanticipated mechanisms, while still conforming to community-level metabolic theory. While warming by 3.8 °C decreased invertebrate abundance in the experimental stream by 60% relative to a reference stream, total invertebrate biomass was unchanged. Associated shifts in invertebrate assemblage structure were driven by the arrival of new taxa and a higher proportion of large, warm-adapted species (i.e., snails and predatory dipterans) relative to small-bodied, cold-adapted taxa (e.g., chironomids and oligochaetes). Experimental warming consequently shifted assemblage size spectra in ways that were unexpected, but consistent with thermal optima of taxa in the regional species pool. Higher temperatures increased community-level energy demand, which was presumably satisfied by higher primary production after warming. Our experiment demonstrates how warming reassembles communities within the constraints of energy supply via regional exchange of species that differ in thermal physiological traits. Similar responses will likely mediate impacts of anthropogenic warming on biodiversity and ecosystem function across all ecological communities. © 2016 John Wiley & Sons Ltd.

Nanocarriers for nuclear imaging and radiotherapy of cancer.

PubMed

Mitra, Amitava; Nan, Anjan; Line, Bruce R; Ghandehari, Hamidreza

2006-01-01

Several nanoscale carriers (nanoparticles, liposomes, water-soluble polymers, micelles and dendrimers) have been developed for targeted delivery of cancer diagnostic and therapeutic agents. These carriers can selectively target cancer sites and carry large payloads, thereby improving cancer detection and therapy effectiveness. Further, the combination of newer nuclear imaging techniques providing high sensitivity and spatial resolution such as dual modality imaging with positron emission tomography/computed tomography (PET/CT) and use of nanoscale devices to carry diagnostic and therapeutic radionuclides with high target specificity can enable more accurate detection, staging and therapy planning of cancer. The successful clinical applications of radiolabeled monoclonal antibodies for cancer detection and therapy bode well for the future of nanoscale carrier systems in clinical oncology. Several radiolabeled multifunctional nanocarriers have been effective in detecting and treating cancer in animal models. Nonetheless, further preclinical, clinical and long-term toxicity studies will be required to translate this technology to the care of patients with cancer. The objective of this review is to present a brief but comprehensive overview of the various nuclear imaging techniques and the use of nanocarriers to deliver radionuclides for the diagnosis and therapy of cancer.

Versions of the Waste Reduction Model (WARM)

EPA Pesticide Factsheets

This page provides a brief chronology of changes made to EPA’s Waste Reduction Model (WARM), organized by WARM version number. The page includes brief summaries of changes and updates since the previous version.

Versions of the Waste Reduction Model (WARM)

EPA Pesticide Factsheets

2017-02-14

This page provides a brief chronology of changes made to EPA’s Waste Reduction Model (WARM), organized by WARM version number. The page includes brief summaries of changes and updates since the previous version.

Reactor-released radionuclides in Susquehanna River sediments

USGS Publications Warehouse

Olsen, C.R.; Larsen, I.L.; Cutshall, N.H.; Donoghue, J.F.; Bricker, O.P.; Simpson, H.J.

1981-01-01

Three Mile Island (TMI) and Peach Bottom (PB) reactors have introduced 137Cs, 134Cs, 60Co, 58Co and several other anthropogenic radionuclides into the lower Susquehanna River. Here we present the release history for these nuclides (Table 1) and radionuclide concentration data (Table 2) for sediment samples collected in the river and upper portions of the Chesapeake Bay (Fig. 1) within a few months after the 28 March 1979 loss-of-coolant-water problem at TMI. Although we found no evidence for nuclides characteristic of a ruptured fuel element, we did find nuclides characteristic of routine operations. Despite the TMI incident, more than 95% of the total 134Cs input to the Susquehanna has been a result of controlled low-level releases from the PB site. 134Cs activity released into the river is effectively trapped by sediments with the major zones of reactor-nuclide accumulation behind Conowingo Dam and in the upper portions of Chesapeake Bay. The reported distributions document the fate of reactor-released radionuclides and their extent of environmental contamination in the Susquehanna-Upper Chesapeake Bay System. ?? 1981 Nature Publishing Group.

Radionuclide development at BNL for nuclear medicine therapy.

PubMed

Mausner, L F; Kolsky, K L; Joshi, V; Srivastava, S C

1998-04-01

Radionuclides with medium energy beta emission and a several day half-life have often been viewed as attractive candidates for radioimmunotherapy. Among the most promising in this category are 47Sc, 67Cu, 153Sm, 188Re, and 199Au. The production of 67Cu, 153Sm, 199Au at BNL is summarized and the development of the latest candidate for this application, 47Sc, is described in detail. We also summarize the development of another important therapeutic radionuclide, 117mSn for bone pain palliation.

DETERMINATION OF REPORTABLE RADIONUCLIDES FOR DWPF SLUDGE BATCH 7B (MACROBATCH 9)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crawford, C. L.; Diprete, D. P.

The Waste Acceptance Product Specifications (WAPS) 1.2 require that “The Producer shall report the inventory of radionuclides (in Curies) that have half-lives longer than 10 years and that are, or will be, present in concentrations greater than 0.05 percent of the total inventory for each waste type indexed to the years 2015 and 3115”. As part of the strategy to comply with WAPS 1.2, the Defense Waste Processing Facility (DWPF) will report for each waste type, all radionuclides (with half-lives greater than 10 years) that have concentrations greater than 0.01 percent of the total inventory from time of production throughmore » the 1100 year period from 2015 through 3115. The initial listing of radionuclides to be included is based on the design-basis glass as identified in the Waste Form Compliance Plan (WCP) and Waste Form Qualification Report (WQR). However, it is required that this list be expanded if other radionuclides with half-lives greater than 10 years are identified that may meet the greater than 0.01% criterion for Curie content. Specification 1.6 of the WAPS, International Atomic Energy Agency (IAEA) Safeguards Reporting for High Level Waste (HLW), requires that the ratio by weights of the following uranium and plutonium isotopes be reported: U-233, U-234, U-235, U-236, U-238, Pu-238, Pu-239, Pu-240, Pu-241, and Pu- 242. Therefore, the complete set of reportable radionuclides must also include this set of U and Pu isotopes. The DWPF is receiving radioactive sludge slurry from HLW Tank 40. The radioactive sludge slurry in Tank 40 is a blend of the heel from Sludge Batch 7a (SB7a) and Sludge Batch 7b (SB7b) that was transferred to Tank 40 from Tank 51. The blend of sludge in Tank 40 is also referred to as Macrobatch 9 (MB9). This report develops the list of reportable radionuclides and associated activities as a function of time. The DWPF will use this list and the activities as one of the inputs for the development of the Production Records that

Determination Of Reportable Radionuclides For DWPF Sludge Batch 7B (Macrobatch 9)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crawford, C. L.; DiPrete, D. P.

The Waste Acceptance Product Specifications (WAPS) 1.2 require that “The Producer shall report the inventory of radionuclides (in Curies) that have half-lives longer than 10 years and that are, or will be, present in concentrations greater than 0.05 percent of the total inventory for each waste type indexed to the years 2015 and 3115”. As part of the strategy to comply with WAPS 1.2, the Defense Waste Processing Facility (DWPF) will report for each waste type, all radionuclides (with half-lives greater than 10 years) that have concentrations greater than 0.01 percent of the total inventory from time of production throughmore » the 1100 year period from 2015 through 3115. The initial listing of radionuclides to be included is based on the design-basis glass as identified in the Waste Form Compliance Plan (WCP) and Waste Form Qualification Report (WQR). However, it is required that this list be expanded if other radionuclides with half-lives greater than 10 years are identified that may meet the greater than 0.01% criterion for Curie content. Specification 1.6 of the WAPS, International Atomic Energy Agency (IAEA) Safeguards Reporting for High Level Waste (HLW), requires that the ratio by weights of the following uranium and plutonium isotopes be reported: U-233, U-234, U-235, U-236, U-238, Pu-238, Pu-239, Pu-240, Pu-241, and Pu-242. Therefore, the complete set of reportable radionuclides must also include this set of U and Pu isotopes. The DWPF is receiving radioactive sludge slurry from HLW Tank 40. The radioactive sludge slurry in Tank 40 is a blend of the heel from Sludge Batch 7a (SB7a) and Sludge Batch 7b (SB7b) that was transferred to Tank 40 from Tank 51. The blend of sludge in Tank 40 is also referred to as Macrobatch 9 (MB9). This report develops the list of reportable radionuclides and associated activities as a function of time. The DWPF will use this list and the activities as one of the inputs for the development of the Production Records that

The recent warming of permafrost in Alaska

NASA Astrophysics Data System (ADS)

Osterkamp, T. E.

2005-12-01

This paper reports results of an experiment initiated in 1977 to determine the effects of climate on permafrost in Alaska. Permafrost observatories with boreholes were established along a north-south transect of Alaska in undisturbed permafrost terrain. The analysis and interpretation of annual temperature measurements in the boreholes and daily temperature measurements of the air, ground and permafrost surfaces made with automated temperature loggers are reported. Permafrost temperatures warmed along this transect coincident with a statewide warming of air temperatures that began in 1977. At two sites on the Arctic Coastal Plain, the warming was seasonal, greatest during "winter" months (October through May) and least during "summer" months (June through September). Permafrost temperatures peaked in the early 1980s and then decreased in response to slightly cooler air temperatures and thinner snow covers. Arctic sites began warming again typically about 1986 and Interior Alaska sites about 1988. Gulkana, the southernmost site, has been warming slowly since it was drilled in 1983. Air temperatures were relatively warm and snow covers were thicker-than-normal from the late 1980s into the late 1990s allowing permafrost temperatures to continue to warm. Temperatures at some sites leveled off or cooled slightly at the turn of the century. Two sites (Yukon River Bridge and Livengood) cooled during the period of observations. The magnitude of the total warming at the surface of the permafrost (through 2003) was 3 to 4 °C for the Arctic Coastal Plain, 1 to 2 °C for the Brooks Range including its northern and southern foothills, and 0.3 to 1 °C south of the Yukon River. While the data are sparse, permafrost is warming throughout the region north of the Brooks Range, southward along the transect from the Brooks Range to the Chugach Mountains (except for Yukon River and Livengood), in Interior Alaska throughout the Tanana River region, and in the region south of the

Microbiological Transformations of Radionuclides in the Subsurface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marshall, Matthew J.; Beliaev, Alex S.; Fredrickson, Jim K.

2010-01-04

Microorganisms are ubiquitous in subsurface environments although their populations sizes and metabolic activities can vary considerably depending on energy and nutrient inputs. As a result of their metabolic activities and the chemical properties of their cell surfaces and the exopolymers they produce, microorganisms can directly or indirectly facilitate the biotransformation of radionuclides, thus altering their solubility and overall fate and transport in the environment. Although biosorption to cell surfaces and exopolymers can be an important factor modifying the solubility of some radionuclides under specific conditions, oxidation state is often considered the single most important factor controlling their speciation and, therefore,more » environmental behavior.« less

Characteristics of radionuclide contamination of different zones of Semipalatinsk Nuclear Test Site ``Opytnoe pole''

NASA Astrophysics Data System (ADS)

Kadyrzhanov, K. K.; Khazhekber, S.; Lukashenko, S. N.; Solodukhin, V. P.; Kazachevskiy, I. V.; Poznyak, V. L.; Knyazev, B. B.; Rofer, Ch.

2003-01-01

Data on the spatial distribution of radionuclides (241Am, 239Pu, 137Cs and 152Eu) formed during nuclear explosions of different types near P2 SNTS test site are presented. Radionuclide contamination induced by the explosions varies in the concentrations of individual radionuclides, their proportions and species. Examination of the variations is a crucial task to plan remediation activities as well as those aimed at decrease of radiation risk for population and prevention of repeated contamination. Concentrations of 241Am and 239+240Pu that are the most toxic radionuclides in the area lie in hundred thousands of Bqkg-1. The most contaminated areas are classified by the radionuclide concentration, ratio and form present in soil.

Vertical structure of recent Arctic warming.

PubMed

Graversen, Rune G; Mauritsen, Thorsten; Tjernström, Michael; Källén, Erland; Svensson, Gunilla

2008-01-03

Near-surface warming in the Arctic has been almost twice as large as the global average over recent decades-a phenomenon that is known as the 'Arctic amplification'. The underlying causes of this temperature amplification remain uncertain. The reduction in snow and ice cover that has occurred over recent decades may have played a role. Climate model experiments indicate that when global temperature rises, Arctic snow and ice cover retreats, causing excessive polar warming. Reduction of the snow and ice cover causes albedo changes, and increased refreezing of sea ice during the cold season and decreases in sea-ice thickness both increase heat flux from the ocean to the atmosphere. Changes in oceanic and atmospheric circulation, as well as cloud cover, have also been proposed to cause Arctic temperature amplification. Here we examine the vertical structure of temperature change in the Arctic during the late twentieth century using reanalysis data. We find evidence for temperature amplification well above the surface. Snow and ice feedbacks cannot be the main cause of the warming aloft during the greater part of the year, because these feedbacks are expected to primarily affect temperatures in the lowermost part of the atmosphere, resulting in a pattern of warming that we only observe in spring. A significant proportion of the observed temperature amplification must therefore be explained by mechanisms that induce warming above the lowermost part of the atmosphere. We regress the Arctic temperature field on the atmospheric energy transport into the Arctic and find that, in the summer half-year, a significant proportion of the vertical structure of warming can be explained by changes in this variable. We conclude that changes in atmospheric heat transport may be an important cause of the recent Arctic temperature amplification.

Global Warming: Lessons from Ozone Depletion

ERIC Educational Resources Information Center

Hobson, Art

2010-01-01

My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

Singer and listener perception of vocal warm-up.

PubMed

Moorcroft, Lynda; Kenny, Dianna T

2013-03-01

This study investigated changes perceived by singers and listeners after the singers had vocally warmed up. The study used a repeated measures within-subject design to assess changes in vibrato quality from pre (nonwarmed-up voice) to post (warmed-up voice) test. Intraclass correlation coefficients were calculated to assess singers' self-ratings pre- and posttest and intra- and interlistener rater reliability. Twelve classically trained female singers recorded and self-rated their performance of an eight bar solo before and after 25 minutes of vocal warm-up exercises. Six experienced listeners assessed the vocal samples for pre- to posttest differences in tone quality and for each singer's warm-up condition. Perceptual judgements were also compared with pre- to posttest changes in vibrato. All singers perceived significant changes in tone quality, psychophysiological factors, proprioceptive feedback and technical command. Significant pre- to posttest differences in tone quality and correct appraisal of the singer's warm-up condition from most of the listeners were only observed for singers who moderated extremely fast or extremely slow vibrato after warming up. The findings reveal the divide between listeners' and singers' perceptions of the warmed-up voice and highlight the importance of enhanced vibrato quality to listener perception of an improvement in vocal quality. Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Behaviour and fluxes of natural radionuclides in the production process of a phosphoric acid plant.

PubMed

Bolívar, J P; Martín, J E; García-Tenorio, R; Pérez-Moreno, J P; Mas, J L

2009-02-01

In recent years there has been an increasing awareness of the occupational and public hazards of the radiological impact of non-nuclear industries which process materials containing naturally occurring radionuclides. These include the industries devoted to the production of phosphoric acid by treating sedimentary phosphate rocks enriched in radionuclides from the uranium series. With the aim of evaluating the radiological impact of a phosphoric acid factory located in the south-western Spain, the distribution and levels of radionuclides in the materials involved in its production process have been analysed. In this way, it is possible to asses the flows of radionuclides at each step and to locate those points where a possible radionuclide accumulation could be produced. A set of samples collected along the whole production process were analysed to determine their radionuclide content by both alpha-particle and gamma spectrometry techniques. The radionuclide fractionation steps and enrichment sources have been located, allowing the establishment of their mass (activity) balances per year.

Revisiting CMB constraints on warm inflation

NASA Astrophysics Data System (ADS)

Arya, Richa; Dasgupta, Arnab; Goswami, Gaurav; Prasad, Jayanti; Rangarajan, Raghavan

2018-02-01

We revisit the constraints that Planck 2015 temperature, polarization and lensing data impose on the parameters of warm inflation. To this end, we study warm inflation driven by a single scalar field with a quartic self interaction potential in the weak dissipative regime. We analyse the effect of the parameters of warm inflation, namely, the inflaton self coupling λ and the inflaton dissipation parameter QP on the CMB angular power spectrum. We constrain λ and QP for 50 and 60 number of e-foldings with the full Planck 2015 data (TT, TE, EE + lowP and lensing) by performing a Markov-Chain Monte Carlo analysis using the publicly available code CosmoMC and obtain the joint as well as marginalized distributions of those parameters. We present our results in the form of mean and 68 % confidence limits on the parameters and also highlight the degeneracy between λ and QP in our analysis. From this analysis we show how warm inflation parameters can be well constrained using the Planck 2015 data.

Global warming in the public sphere.

PubMed

Corfee-Morlot, Jan; Maslin, Mark; Burgess, Jacquelin

2007-11-15

Although the science of global warming has been in place for several decades if not more, only in the last decade and a half has the issue moved clearly into the public sphere as a public policy issue and a political priority. To understand how and why this has occurred, it is essential to consider the history of the scientific theory of the greenhouse effect, the evidence that supports it and the mechanisms through which science interacts with lay publics and other elite actors, such as politicians, policymakers and business decision makers. This article reviews why and how climate change has moved from the bottom to the top of the international political agenda. It traces the scientific discovery of global warming, political and institutional developments to manage it as well as other socially mediated pathways for understanding and promoting global warming as an issue in the public sphere. The article also places this historical overview of global warming as a public issue into a conceptual framework for understanding relationships between society and nature with emphasis on the co-construction of knowledge.

Radionuclide transfer to fruit in the IAEA TRS No. 472

NASA Astrophysics Data System (ADS)

Carini, F.; Pellizzoni, M.; Giosuè, S.

2012-04-01

This paper describes the approach taken to present the information on fruits in the IAEA report TRS No. 472, supported by the IAEA-TECDOC-1616, which describes the key transfer processes, concepts and conceptual models regarded as important for dose assessment, as well as relevant parameters for modelling radionuclide transfer in fruits. Information relate to fruit plants grown in agricultural ecosystems of temperate regions. The relative significance of each pathway after release of radionuclides depends upon the radionuclide, the kind of crop, the stage of plant development and the season at time of deposition. Fruit intended as a component of the human diet is borne by plants that are heterogeneous in habits, and morphological and physiological traits. Information on radionuclides in fruit systems has therefore been rationalised by characterising plants in three groups: woody trees, shrubs, and herbaceous plants. Parameter values have been collected from open literature, conference proceedings, institutional reports, books and international databases. Data on root uptake are reported as transfer factor values related to fresh weight, being consumption data for fruits usually given in fresh weight.

Nuclear cardiac imaging: Principles and applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iskandrian, A.S.

1987-01-01

This book is divided into 11 chapters. The first three provide a short description of the instrumentation, radiopharmaceuticals, and imaging techniques used in nuclear cardiology. Chapter 4 discusses exercise testing. Chapter 5 gives the theory, technical aspects, and interpretations of thallium-201 myocardial imaging and radionuclide ventriculography. The remaining chapters discuss the use of these techniques in patients with coronary artery disease, acute myocardial infarction, valvular heart disease, and other forms of cardiac disease. The author intended to emphasize the implications of nuclear cardiology procedures on patient care management and to provide a comprehensive bibliography.

Accumulation of artificial radionuclides in deep sediments of the Mediterranean Sea

NASA Astrophysics Data System (ADS)

Garcia-Orellana, J.; Sanchez-Cabeza, J. A.; Masque, P.; Costa, E.; Bruach, J. M.; Morist, A.; Luna, J. A.

2003-04-01

Concentrations and inventories of artificial radionuclides (90Sr, 137Cs and 239,40Pu) were determined in deep sediment cores (3.000 m) collected in the western and eastern basins of the Mediterranean Sea in the frame of the ADIOS project. Artificial radionuclides enter the Mediterranean Sea mainly though atmospheric deposition after nuclear weapons tests and the Chernobyl accident, but also through the river discharge of effluents of nuclear facilities (e.g. Rhone and Ebro rivers). The aim of this work is to investigate the degree by which pollutants are transferred to the deep environment of the Mediterranean Sea as a basis to elucidate their effects on benthic organisms. The mean inventories of 239+240Pu, 137Cs and 90Sr in the Western basin are 2.77 ± 0.26, 68 ± 12 and < 7 Bq\\cdotm-2 respectively and 3.29 ± 0.60, 115 ± 33 and 249±154 Bq\\cdotm-2 in the Eastern basin. The activity - depth profiles of 210Pb, together with 14C dating, indicate that sediment mixing redistributes the artificial radionuclides within the first 2 cm of the sedimentary column. Artificial radionuclides inventories in the deep-sea sediments were used to calculate the fraction of the total inventory of artificial radionuclides that is accumulated in the deep sea sediments after scavenging from the water column. Indeed, a balance of the radionuclide distributions in the water column allows evaluating the importance of lateral transport of particulate matter from the continental margins on the accumulation of artificial radionuclides in the deep, open Mediterranean Sea. This is achieved in i) comparison with reported data from coastal areas at different locations in the Mediterranean Sea, and ii) balance of the distribution of the natural radionuclide 210Pb in studied areas (vertical profiles of dissolved and particulate activities, fluxes determined by using sediment trap deployed at different depths and inventories in the bottom sediments). The results, taking into account radioactive

40 CFR Appendix D to Part 61 - Methods for Estimating Radionuclide Emissions

Code of Federal Regulations, 2011 CFR

2011-07-01

... Table 1. Table 1—Adjustment to Emission Factors for Effluent Controls Controls Types of radionuclides... applicable to gaseous radionuclides; periodic testing is prudent to ensure high removal efficiency. Fabric...

40 CFR Appendix D to Part 61 - Methods for Estimating Radionuclide Emissions

Code of Federal Regulations, 2013 CFR

2013-07-01

... Table 1. Table 1—Adjustment to Emission Factors for Effluent Controls Controls Types of radionuclides... applicable to gaseous radionuclides; periodic testing is prudent to ensure high removal efficiency. Fabric...

Chemical fractionation of radionuclides and stable elements in aquatic plants of the Yenisei River.

PubMed

Bolsunovsky, Alexander

2011-09-01