In‐loop flow [11C]CO2 fixation and radiosynthesis of N,N′‐[11C]dibenzylurea

PubMed Central

Downey, Joseph; Bongarzone, Salvatore; Hader, Stefan

2017-01-01

Cyclotron‐produced carbon‐11 is a highly valuable radionuclide for the production of positron emission tomography (PET) radiotracers. It is typically produced as relatively unreactive carbon‐11 carbon dioxide ([11C]CO2), which is most commonly converted into a more reactive precursor for synthesis of PET radiotracers. The development of [11C]CO2 fixation methods has more recently enabled the direct radiolabelling of a diverse array of structures directly from [11C]CO2, and the advantages afforded by the use of a loop‐based system used in 11C‐methylation and 11C‐carboxylation reactions inspired us to apply the [11C]CO2 fixation “in‐loop.” In this work, we developed and investigated a new ethylene tetrafluoroethylene (ETFE) loop‐based [11C]CO2 fixation method, enabling the fast and efficient, direct‐from‐cyclotron, in‐loop trapping of [11C]CO2 using mixed DBU/amine solutions. An optimised protocol was integrated into a proof‐of‐concept in‐loop flow radiosynthesis of N,N′‐[11C]dibenzylurea. This reaction exhibited an average 78% trapping efficiency and a crude radiochemical purity of 83% (determined by radio‐HPLC), giving an overall nonisolated radiochemical yield of 72% (decay‐corrected) within just 3 minutes from end of bombardment. This proof‐of‐concept reaction has demonstrated that efficient [11C]CO2 fixation can be achieved in a low‐volume (150 μL) ETFE loop and that this can be easily integrated into a rapid in‐loop flow radiosynthesis of carbon‐11–labelled products. This new in‐loop methodology will allow fast radiolabelling reactions to be performed using cheap/disposable ETFE tubing setup (ideal for good manufacturing practice production) thereby contributing to the widespread usage of [11C]CO2 trapping/fixation reactions for the production of PET radiotracers. PMID:28977686

In-loop flow [11 C]CO2 fixation and radiosynthesis of N,N'-[11 C]dibenzylurea.

PubMed

Downey, Joseph; Bongarzone, Salvatore; Hader, Stefan; Gee, Antony D

2018-03-01

Cyclotron-produced carbon-11 is a highly valuable radionuclide for the production of positron emission tomography (PET) radiotracers. It is typically produced as relatively unreactive carbon-11 carbon dioxide ([ 11 C]CO 2 ), which is most commonly converted into a more reactive precursor for synthesis of PET radiotracers. The development of [ 11 C]CO 2 fixation methods has more recently enabled the direct radiolabelling of a diverse array of structures directly from [ 11 C]CO 2 , and the advantages afforded by the use of a loop-based system used in 11 C-methylation and 11 C-carboxylation reactions inspired us to apply the [ 11 C]CO 2 fixation "in-loop." In this work, we developed and investigated a new ethylene tetrafluoroethylene (ETFE) loop-based [ 11 C]CO 2 fixation method, enabling the fast and efficient, direct-from-cyclotron, in-loop trapping of [ 11 C]CO 2 using mixed DBU/amine solutions. An optimised protocol was integrated into a proof-of-concept in-loop flow radiosynthesis of N,N'-[ 11 C]dibenzylurea. This reaction exhibited an average 78% trapping efficiency and a crude radiochemical purity of 83% (determined by radio-HPLC), giving an overall nonisolated radiochemical yield of 72% (decay-corrected) within just 3 minutes from end of bombardment. This proof-of-concept reaction has demonstrated that efficient [ 11 C]CO 2 fixation can be achieved in a low-volume (150 μL) ETFE loop and that this can be easily integrated into a rapid in-loop flow radiosynthesis of carbon-11-labelled products. This new in-loop methodology will allow fast radiolabelling reactions to be performed using cheap/disposable ETFE tubing setup (ideal for good manufacturing practice production) thereby contributing to the widespread usage of [ 11 C]CO 2 trapping/fixation reactions for the production of PET radiotracers. © 2017 The Authors. Journal of Labelled Compounds and Radiopharmaceuticals Published by John Wiley & Sons, Ltd.

Safety and Waste Management for SAM Radiochemical Methods

EPA Pesticide Factsheets

The General Safety and Waste Management page offers section-specific safety and waste management details for the radiochemical analytes included in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).

Recovery of 131I from alkaline solution of n-irradiated tellurium target using a tiny Dowex-1 column.

PubMed

Chattopadhyay, Sankha; Saha Das, Sujata

2010-10-01

A simple and inexpensive ion-exchange chromatography method for the separation of medically useful no-carrier-added (nca) iodine radionuclides from bulk amounts of irradiated tellurium dioxide (TeO(2)) target was developed and tested using (131)I. The radiochemical separation was performed using a very small Dowex-1x8 ion-exchange column. The overall radiochemical yield for the complete separation of (131)I was 92+/-1.8 (standard deviation) % (n=8). The separated nca (131)I was of high, approximately 99%, radionuclidic and radiochemical purity and did not contain detectable amounts of the target material. This method may be adopted for the radiochemical separation of other different iodine radionuclides produced from tellurium matrices through cyclotron as well as reactor irradiation. Copyright 2010 Elsevier Ltd. All rights reserved.

Radiochemical Solar Neutrino Experiments - Successful and Otherwise.

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

Hahn,R.L.

2008-05-25

Over the years, several different radiochemical systems have been proposed as solar neutrino detectors. Of these, two achieved operating status and obtained important results that helped to define the current field of neutrino physics: the first solar-neutrino experiment, the Chlorine Detector ({sup 37}Cl) that was developed by chemist Raymond Davis and colleagues at the Homestake Mine, and the subsequent Gallium ({sup 71}Ga) Detectors that were operated by (a) the SAGE collaboration at the Baksan Laboratory and (b) the GALLEX/GNO collaborations at the Gran Sasso National Laboratory. These experiments have been extensively discussed in the literature and in many previous Internationalmore » Neutrino Conferences. In this paper, I present important updates to the results from SAGE and GALLEX/GNO. I also review the principles of the radiochemical detectors and briefly describe several different detectors that have been proposed. In light of the well-known successes that have been subsequently obtained by real-time neutrino detectors such as Kamiokande, Super-Kamiokande, SNO, and KamLAND, I do not anticipate that any new radiochemical neutrino detectors will be built. At present, only SAGE is still operating; the Chlorine and GNO radiochemical detectors have been decommissioned and dismantled.« less

Rapid and Efficient Conversion of (11) CO2 to (11) CO through Silacarboxylic Acids: Applications in Pd-Mediated Carbonylations.

PubMed

Nordeman, Patrik; Friis, Stig D; Andersen, Thomas L; Audrain, Hélène; Larhed, Mats; Skrydstrup, Troels; Antoni, Gunnar

2015-12-01

Herein, we present a new rapid, efficient, and low-cost radiosynthetic protocol for the conversion of (11) CO2 to (11) CO and its subsequent application in Pd-mediated reactions of importance for PET applications. This room-temperature methodology, using readily available chemical reagents, is carried out in simple glass vials, thus eliminating the need for expensive and specialized high-temperature equipment to access (11) CO. With this fast and near-quantitative conversion of (11) CO2 into (11) CO, aryl and heteroaryl iodides were easily converted into a broad selection of biologically active amides in radiochemical yields ranging from 29-84 %. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Preparation of Radiolabeled Compounds for the U.S. Army Drug Development Program.

DTIC Science & Technology

1996-12-01

with borane -THF complex gave an 83% radiochemical yield of [14C]-19 after several recrystallizations from ethanol. In the master synthesis , alcohol...amide [14C]-15 in 88% radiochemical yield and 99% radiochemical purity after chromatography. Reduction of [14C]-15 with borane -THF complex afforded a...163 mCi) and tetrahydrofuran (freshly distilled) (28.6 mL) in a 1 00-mL RBF was cooled to 0 0C by an ice-bath. Borane -tetra- hydrofuran complex (10.8 mL

Radiosynthesis of [18F]Trifluoroalkyl Groups: Scope and Limitations

PubMed Central

Riss, P. J.

2014-01-01

The present paper is concerned with radiochemical methodology to furnish the trifluoromethyl motif labelled with 18F. Literature spanning the last four decades is comprehensively reviewed and radiochemical yields and specific activities are discussed. PMID:25110676

Annual water-resources review, White Sands Missile Range, New Mexico, 1984

USGS Publications Warehouse

Cruz, R.R.

1985-01-01

Hydrologic data were collected at White Sands Missile Range in 1984. The total groundwater withdrawal in 1984 was 685,275,000 gallons. The Post Headquarters well field produced 650,821,000 gallons in 1984. Six new wells were drilled at White Sands Missile Range in 1984. Nineteen water samples were collected for major chemical-constituent, trace-element, or radiochemical analysis in 1984. Depth-to-water measurements in the Post Headquarters supply wells showed seasonal fluctuations as well as continued long-term declines. (USGS)

Preliminary Therapy Evaluation of 225Ac-DOTA-c(RGDyK) Demonstrates that Cerenkov Radiation Derived from 225Ac Daughter Decay Can Be Detected by Optical Imaging for In Vivo Tumor Visualization

PubMed Central

Pandya, Darpan N.; Hantgan, Roy; Budzevich, Mikalai M.; Kock, Nancy D.; Morse, David L.; Batista, Izadora; Mintz, Akiva; Li, King C.; Wadas, Thaddeus J.

2016-01-01

The theranostic potential of 225Ac-based radiopharmaceuticals continues to increase as researchers seek innovative ways to harness the nuclear decay of this radioisotope for therapeutic and imaging applications. This communication describes the evaluation of 225Ac-DOTA-c(RGDyK) in both biodistribution and Cerenkov luminescence imaging (CLI) studies. Initially, La-DOTA-c(RGDyK) was prepared as a non-radioactive surrogate to evaluate methodologies that would contribute to an optimized radiochemical synthetic strategy and estimate the radioactive conjugate's affinity for αvβ3, using surface plasmon resonance spectroscopy. Surface plasmon resonance spectroscopy studies revealed the IC50 and Ki of La-DOTA-c(RGDyK) to be 33 ± 13 nM and 26 ± 11 nM, respectively, and suggest that the complexation of the La3+ ion to the conjugate did not significantly alter integrin binding. Furthermore, use of this surrogate allowed optimization of radiochemical synthesis strategies to prepare 225Ac-DOTA-c(RGDyK) with high radiochemical purity and specific activity similar to other 225Ac-based radiopharmaceuticals. This radiopharmaceutical was highly stable in vitro. In vivo biodistribution studies confirmed the radiotracer's ability to target αvβ3 integrin with specificity; specificity was detected in tumor-bearing animals using Cerenkov luminescence imaging. Furthermore, tumor growth control was achieved using non-toxic doses of the radiopharmaceutical in U87mg tumor-bearing nude mice. To our knowledge, this is the first report to describe the CLI of αvβ3+ tumors in live animals using the daughter products derived from 225Ac decay in situ. This concept holds promise to further enhance development of targeted alpha particle therapy. PMID:27022417

Preliminary Therapy Evaluation of (225)Ac-DOTA-c(RGDyK) Demonstrates that Cerenkov Radiation Derived from (225)Ac Daughter Decay Can Be Detected by Optical Imaging for In Vivo Tumor Visualization.

PubMed

Pandya, Darpan N; Hantgan, Roy; Budzevich, Mikalai M; Kock, Nancy D; Morse, David L; Batista, Izadora; Mintz, Akiva; Li, King C; Wadas, Thaddeus J

2016-01-01

The theranostic potential of (225)Ac-based radiopharmaceuticals continues to increase as researchers seek innovative ways to harness the nuclear decay of this radioisotope for therapeutic and imaging applications. This communication describes the evaluation of (225)Ac-DOTA-c(RGDyK) in both biodistribution and Cerenkov luminescence imaging (CLI) studies. Initially, La-DOTA-c(RGDyK) was prepared as a non-radioactive surrogate to evaluate methodologies that would contribute to an optimized radiochemical synthetic strategy and estimate the radioactive conjugate's affinity for αvβ3, using surface plasmon resonance spectroscopy. Surface plasmon resonance spectroscopy studies revealed the IC50 and Ki of La-DOTA-c(RGDyK) to be 33 ± 13 nM and 26 ± 11 nM, respectively, and suggest that the complexation of the La(3+) ion to the conjugate did not significantly alter integrin binding. Furthermore, use of this surrogate allowed optimization of radiochemical synthesis strategies to prepare (225)Ac-DOTA-c(RGDyK) with high radiochemical purity and specific activity similar to other (225)Ac-based radiopharmaceuticals. This radiopharmaceutical was highly stable in vitro. In vivo biodistribution studies confirmed the radiotracer's ability to target αvβ3 integrin with specificity; specificity was detected in tumor-bearing animals using Cerenkov luminescence imaging. Furthermore, tumor growth control was achieved using non-toxic doses of the radiopharmaceutical in U87mg tumor-bearing nude mice. To our knowledge, this is the first report to describe the CLI of αvβ3 (+) tumors in live animals using the daughter products derived from (225)Ac decay in situ. This concept holds promise to further enhance development of targeted alpha particle therapy.

Simplified NaCl based (68)Ga concentration and labeling procedure for rapid synthesis of (68)Ga radiopharmaceuticals in high radiochemical purity.

PubMed

Mueller, Dirk; Klette, Ingo; Baum, Richard P; Gottschaldt, M; Schultz, Michael K; Breeman, Wouter A P

2012-08-15

A simple sodium chloride (NaCl) based (68)Ga eluate concentration and labeling method that enables rapid, high-efficiency labeling of DOTA conjugated peptides in high radiochemical purity is described. The method utilizes relatively few reagents and comprises minimal procedural steps. It is particularly well-suited for routine automated synthesis of clinical radiopharmaceuticals. For the (68)Ga generator eluate concentration step, commercially available cation-exchange cartridges and (68)Ga generators were used. The (68)Ga generator eluate was collected by use of a strong cation exchange cartridge. 98% of the total activity of (68)Ga was then eluted from the cation exchange cartridge with 0.5 mL of 5 M NaCl solution containing a small amount of 5.5 M HCl. After buffering with ammonium acetate, the eluate was used directly for radiolabeling of DOTATOC and DOTATATE. The (68)Ga-labeled peptides were obtained in higher radiochemical purity compared to other commonly used procedures, with radiochemical yields greater than 80%. The presence of (68)Ge could not be detected in the final product. The new method obviates the need for organic solvents, which eliminates the required quality control of the final product by gas chromatography, thereby reducing postsynthesis analytical effort significantly. The (68)Ga-labeled products were used directly, with no subsequent purification steps, such as solid-phase extraction. The NaCl method was further evaluated using an automated fluid handling system and it routinely facilitates radiochemical yields in excess of 65% in less than 15 min, with radiochemical purity consistently greater than 99% for the preparation of (68)Ga-DOTATOC.

Fast and repetitive in-capillary production of [18F]FDG.

PubMed

Wester, Hans-Jürgen; Schoultz, Bent Wilhelm; Hultsch, Christina; Henriksen, Gjermund

2009-04-01

The increasing demand for radiopharmaceuticals to be provided reproducibly and flexibly with high frequency for clinical application and animal imaging would be better met by improved or even new strategies for automated tracer production. Radiosynthesis in microfluidic systems, i.e. narrow tubing with a diameter of approximately 50-500 microm, holds promise for providing the means for repetitive multidose and multitracer production. In this study, the performance of a conceptually simple microfluidic device integrated into a fully automated synthesis procedure for in-capillary radiosynthesis (ICR) of clinical grade [(18)F]FDG was evaluated. The instrumental set-up consisted of pumps for reagent and solvent delivery into small mixing chambers, micro-fluidic capillaries, in-process radioactivity monitoring, solid-phase extraction and on-column deprotection of the (18)F-labelled intermediate followed by on-line formulation of [(18)F]FDG. In-capillary(18)F-fluorination of 2.1 micromol 1,3,4,6-tetra-O-acetyl-2-O-trifluoromethanesulphonyl-beta-D-mannopyranose (TATM; precursor for [(18)F]FDG) in acetonitrile (MeCN) at a flow rate of 0.3 ml/min within 40 s and subsequent on-line hydrolysis of the intermediate by treatment with 0.3 M NaOH for 1 min at 40 degrees C resulted in a radiochemical yield of 88 +/- 4% within <7 min. Reproducibility, robustness and suitability as a fast and efficient radiopharmaceutical research tool for (18)F-fluorination was demonstrated by eight independent, sequentially performed ICRs which provided identical tracer quality (radiochemical purity >97%, MeCN <5 microg/ml) and similar absolute yields (approximately 1.4 GBq). The described ICR process is a simple and efficient alternative to classic radiotracer production systems and provides a comparatively cheap instrumental methodology for the repetitive production of [(18)F]FDG with remarkably high efficiency and high yield under fully automated conditions. Although the results concerning the levels of activity need to be confirmed after installation of the equipment in a suitable GMP hot-cell environment, we expect the instrumental design to allow up-scaling without major difficulties or fundamental restrictions. Furthermore, we are convinced that similar or nearly identical procedures, and thus instrumentation, will allow ICR of other (18)F-labelled radiopharmaceuticals.

Analytical Chemistry Division. Annual progress report for period ending December 31, 1980

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

Lyon, W.S.

1981-05-01

This report is divided into: analytical methodology; mass and emission spectrometry; technical support; bio/organic analysis; nuclear and radiochemical analysis; quality assurance, safety, and tabulation of analyses; supplementary activities; and presentation of research results. Separate abstracts were prepared for the technical support, bio/organic analysis, and nuclear and radiochemical analysis. (DLC)

A simple and rapid radiochemical choline acetyltransferase (ChAT) assay screening test.

PubMed

Shiba, Kazuhiro; Ogawa, Kazuma; Kinuya, Seigo; Yajima, Kazuyoshi; Mori, Hirofumi

2006-10-15

A simple radiochemical choline acetyltransferase (ChAT) assay screening test was developed by measuring for [(3)H]acetylcholine ([(3)H]ACh) formed from 0.2 mM [(3)H]acetyl-coenzyme A ([(3)H]acetyl-CoA) and 1 mM choline by 0.2 mg of rat brain homogenates containing ChAT into 96-well microplates. A simple and rapid procedure for isolating [(3)H]ACh from the incubation mixture into 96-well microplates was achieved by using a sodium tetraphenylboron (Kalibor) solution (in ethyl acetate, 0.75%, w/v) and a hydrophobic liquid scintillator mixture (1:5, v/v, 0.2 mL) as an extraction solvent. The benefits of this radiochemical method using 96-well microplates are as follows: (1) this method is reliable and reproducible; (2) many samples can be examined at the same time by this method; (3) this method is economical and effective in reducing radioactive waste. The development of a new simple radiochemical ChAT assay screening test is the first stage of development of radiolabeled ChAT mapping agent.

Evaluation of the Possible Utilization of 68Ga-DOTATOC in Diagnosis of Adenocarcinoma Breast Cancer.

PubMed

Zolghadri, Samaneh; Naderi, Mojdeh; Yousefnia, Hassan; Alirezapour, Behrouz; Beiki, Davood

2018-01-01

Studies have indicated advantageous properties of [DOTA-DPhe 1 , Tyr 3 ] octreotide (DOTATOC) in tumor models and labeling with gallium. Breast cancer is the second leading cause of cancer mortality in women, and most of these cancers are often an adenocarcinoma. Due to the importance of target to non-target ratios in the efficacy of diagnosis, the pharmacokinetic of 68 Ga-DOTATOC in an adenocarcinoma breast cancer animal model was studied in this research, and the optimized time for imaging was determined. 68 Ga was obtained from 68 Ge/ 68 Ga generator. The complex was prepared at optimized conditions. Radiochemical purity of the complex was checked using both HPLC and ITLC methods. Biodistribution of the complex was studied in BALB/c mice bearing adenocarcinoma breast cancer. Also, PET/CT imaging was performed up to 120 min post injection. The complex was produced with radiochemical purity of greater than 98% and specific activity of about 40 GBq/mM at optimized conditions. Biodistribution of the complex was studied in BALB/c mice bearing adenocarcinoma breast cancer indicated fast blood clearance and significant uptake in the tumor. Significant tumor: blood and tumor:muscle uptake ratios were observed even at early times post-injection. PET/CT images were also confirmed the considerable accumulation of the tracer in the tumor. Generally, the results proved the possible application of the radiolabelled complex for the detection of the adenocarcinoma breast cancer and according to the pharmacokenitic data, the suitable time for imaging was determined as at least 30 min after injection.

Evaluation of the Possible Utilization of 68Ga-DOTATOC in Diagnosis of Adenocarcinoma Breast Cancer

PubMed Central

Zolghadri, Samaneh; Naderi, Mojdeh; Yousefnia, Hassan; Alirezapour, Behrouz; Beiki, Davood

2018-01-01

Objective(s): Studies have indicated advantageous properties of [DOTA-DPhe1, Tyr3] octreotide (DOTATOC) in tumor models and labeling with gallium. Breast cancer is the second leading cause of cancer mortality in women, and most of these cancers are often an adenocarcinoma. Due to the importance of target to non-target ratios in the efficacy of diagnosis, the pharmacokinetic of 68Ga-DOTATOC in an adenocarcinoma breast cancer animal model was studied in this research, and the optimized time for imaging was determined. Methods: 68Ga was obtained from 68Ge/68Ga generator. The complex was prepared at optimized conditions. Radiochemical purity of the complex was checked using both HPLC and ITLC methods. Biodistribution of the complex was studied in BALB/c mice bearing adenocarcinoma breast cancer. Also, PET/CT imaging was performed up to 120 min post injection. Results: The complex was produced with radiochemical purity of greater than 98% and specific activity of about 40 GBq/mM at optimized conditions. Biodistribution of the complex was studied in BALB/c mice bearing adenocarcinoma breast cancer indicated fast blood clearance and significant uptake in the tumor. Significant tumor: blood and tumor:muscle uptake ratios were observed even at early times post-injection. PET/CT images were also confirmed the considerable accumulation of the tracer in the tumor. Conclusion: Generally, the results proved the possible application of the radiolabelled complex for the detection of the adenocarcinoma breast cancer and according to the pharmacokenitic data, the suitable time for imaging was determined as at least 30 min after injection. PMID:29333466

Strongly Acidic Auxin Indole-3-Methanesulfonic Acid

PubMed Central

Cohen, Jerry D.; Baldi, Bruce G.; Bialek, Krystyna

1985-01-01

A radiochemical synthesis is described for [14C]indole-3-methanesulfonic acid (IMS), a strongly acidic auxin analog. Techniques were developed for fractionation and purification of IMS using normal and reverse phase chromatography. In addition, the utility of both Fourier transform infrared spectrometry and fast atom bombardment mass spectrometry for analysis of IMS has been demonstrated. IMS was shown to be an active auxin, stimulating soybean hypocotyl elongation, bean first internode curvature, and ethylene production. IMS uptake by thin sections of soybean hypocotyl was essentially independent of solution pH and, when applied at a 100 micromolar concentration, IMS exhibited a basipetal polarity in its transport in both corn coleoptile and soybean hypocotyl sections. [14C]IMS should, therefore, be a useful compound to study fundamental processes related to the movement of auxins in plant tissues and organelles. PMID:16664007

Rapid Radiochemical Methods for Asphalt Paving Material ...

EPA Pesticide Factsheets

Technical Brief Validated rapid radiochemical methods for alpha and beta emitters in solid matrices that are commonly encountered in urban environments were previously unavailable for public use by responding laboratories. A lack of tested rapid methods would delay the quick determination of contamination levels and the assessment of acceptable site-specific exposure levels. Of special concern are matrices with rough and porous surfaces, which allow the movement of radioactive material deep into the building material making it difficult to detect. This research focuses on methods that address preparation, radiochemical separation, and analysis of asphalt paving materials and asphalt roofing shingles. These matrices, common to outdoor environments, challenge the capability and capacity of very experienced radiochemistry laboratories. Generally, routine sample preparation and dissolution techniques produce liquid samples (representative of the original sample material) that can be processed using available radiochemical methods. The asphalt materials are especially difficult because they do not readily lend themselves to these routine sample preparation and dissolution techniques. The HSRP and ORIA coordinate radiological reference laboratory priorities and activities in conjunction with HSRP’s Partner Process. As part of the collaboration, the HSRP worked with ORIA to publish rapid radioanalytical methods for selected radionuclides in building material matrice

Drug composition matters: the influence of carrier concentration on the radiochemical purity, hydroxyapatite affinity and in-vivo bone accumulation of the therapeutic radiopharmaceutical 188Rhenium-HEDP.

PubMed

Lange, R; de Klerk, J M H; Bloemendal, H J; Ramakers, R M; Beekman, F J; van der Westerlaken, M M L; Hendrikse, N H; Ter Heine, R

2015-05-01

(188)Rhenium-HEDP is an effective bone-targeting therapeutic radiopharmaceutical, for treatment of osteoblastic bone metastases. It is known that the presence of carrier (non-radioactive rhenium as ammonium perrhenate) in the reaction mixture during labeling is a prerequisite for adequate bone affinity, but little is known about the optimal carrier concentration. We investigated the influence of carrier concentration in the formulation on the radiochemical purity, in-vitro hydroxyapatite affinity and the in-vivo bone accumulation of (188)Rhenium-HEDP in mice. The carrier concentration influenced hydroxyapatite binding in-vitro as well as bone accumulation in-vivo. Variation in hydroxyapatite binding with various carrier concentrations seemed to be mainly driven by variation in radiochemical purity. The in-vivo bone accumulation appeared to be more complex: satisfactory radiochemical purity and hydroxyapatite affinity did not necessarily predict acceptable bio-distribution of (188)Rhenium-HEDP. For development of new bisphosphonate-based radiopharmaceuticals for clinical use, human administration should not be performed without previous animal bio-distribution experiments. Furthermore, our clinical formulation of (188)Rhenium-HEDP, containing 10 μmol carrier, showed excellent bone accumulation that was comparable to other bisphosphonate-based radiopharmaceuticals, with no apparent uptake in other organs. Radiochemical purity and in-vitro hydroxyapatite binding are not necessarily predictive of bone accumulation of (188)Rhenium-HEDP in-vivo. The formulation for (188)Rhenium-HEDP as developed by us for clinical use exhibits excellent bone uptake and variation in carrier concentration during preparation of this radiopharmaceutical should be avoided. Copyright © 2015 Elsevier Inc. All rights reserved.

Radiolabeling and in vitro and in vivo characterization of [18F]FB-[R(8,15,21), L17]-VIP as a PET imaging agent for tumor overexpressed VIP receptors.

PubMed

Cheng, Dengfeng; Yin, Duanzhi; Li, Gucai; Wang, Mingwei; Li, Shiqiang; Zheng, Mingqiang; Cai, Hancheng; Wang, Yongxian

2006-12-01

In an effort to develop a peptide-based radiopharmaceutical for the detection of tumors overexpressed vasoactive intestinal peptide receptors with positron emission tomography, we have prepared a novel [R(8,15,21), L17]-VIP peptide for 18F-labeling. This peptide inhibited 125I-VIP binding to rats lung membranes with high affinity [half-maximal inhibitory concentrations (IC50) of 0.12 nm]. Additionally, [R(8,15,21), L17]-VIP showed higher stability than native vasoactive intestinal peptide in vivo of mice. With N-succinimidyl 4-[18F] fluorobenzoate as labeling prosthetic group, [18F]FB-[R(8,15,21), L17]-VIP was obtained in >99% radiochemical purity within 100 min in decay-for-corrected radiochemical yield of 33.6 +/- 3% (n = 5) and a specific radioactivity 255 GBq/micromol at the end of synthesis. Stability of [18F]FB-[R(8,15,21), L17]-VIP in vitro and in vivo were investigated. Biodistribution of this trace was carried out in mice with induced C26 colorectal tumor. Fast clearance of [18F]FB-[R(8,15,21), L17]-VIP from non-target tissues and specific uptakes by tumors realized higher tumor-to-muscle ratio (3.55) and tumor-to-blood ratio (2.37) 60 min postinjection. Clear difference was observed between the blocking and unblocking experiments in biodistribution and whole body radioautography. [18F]FB-[R(8,15,21), L17]-VIP has demonstrated its potential for diagnosing tumors overexpressed vasoactive intestinal peptide receptors both in vitro and in vivo.

On the degelation of networks – Case of the radiochemical degradation of methyl methacrylate – ethylene glycol dimethacrylate copolymers

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

Richaud, Emmanuel; Gilormini, Pierre; Verdu, Jacques

2016-05-18

Methyl methacrylate networks were synthetized and submitted to radiochemical degradation. Ageing was monitored by means of sol-gel analysis and glass transition temperature measurements. Networks were shown to undergo exclusively chain scission process leading to the degelation of network. The critical conversion degree corresponding to degelation (loss of all elastically active chains) is discussed regarding a statistical theory.

Radiochemical determination of strontium-90 and cesium-137 in waters of the Pacific Ocean and its neighboring seas

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

Borisenko, G.S.; Kandinskii, P.A.; Gedeonov, L.I.

1987-03-01

Depending on the salinity of the water, two versions of strontium-90 and cesium-137 concentration from water samples are presented. Cesium-137 was concentrated by precipitating sparingly soluble mixed hexacyanoferrates (II), and strontium-90 by precipitating carbonates together with calcium. A scheme has been given for radiochemical analysis of the concentrates. Strontium-90 and cesium-137 contents in the waters of the Pacific Ocean and its neighboring seas have been determined by the radiochemical method described. The levels of radionuclide content in the water and atmospheric precipitations have been shown to be inter-related. Strontium-90 and cesium-137 contents in the surface water of the northwestern Pacificmore » were found to be much lower in 1980 than in the early seventies. The area of technogenic radioactive pollution was found to persist in the region of the Columbia mouth into the Pacific Ocean.« less

Synthesis of empagliflozin, a novel and selective sodium-glucose co-transporter-2 inhibitor, labeled with carbon-14 and carbon-13.

PubMed

Hrapchak, Matt; Latli, Bachir; Wang, Xiao-Jun; Lee, Heewon; Campbell, Scot; Song, Jinhua J; Senanayake, Chris H

2014-10-01

Empagliflozin, (2S,3R,4R,5S,6R)-2-[4-chloro-3-[[4-[(3S)-oxolan-3-yl]oxyphenyl]methyl]phenyl]-6-(hydroxymethyl)oxane-3,4,5-triol was recently approved by the FDA for the treatment of chronic type 2 diabetes mellitus. Herein, we report the synthesis of carbon-13 and carbon-14 labeled empagliflozin. Carbon-13 labeled empagliflozin was prepared in five steps and in 34% overall chemical yield starting from the commercially available α-D-glucose-[(13)C6]. For the radiosynthesis, the carbon-14 atom was introduced in three different positions of the molecule. In the first synthesis, Carbon-14 D-(+)-gluconic acid δ-lactone was used to prepare specifically labeled empagliflozin in carbon-1 of the sugar moiety in four steps and in 19% overall radiochemical yield. Carbon-14 labeled empagliflozin with the radioactive atom in the benzylic position was obtained in eight steps and in 7% overall radiochemical yield. In the last synthesis carbon-14 uniformly labeled phenol was used to give [(14)C]empagliflozin in eight steps and in 18% overall radiochemical yield. In all these radiosyntheses, the specific activities of the final compounds were higher than 53 mCi/mmol, and the radiochemical purities were above 98.5%. Copyright © 2014 John Wiley & Sons, Ltd.

Study of holmium (III) and yttrium(III) with DOTA complexes as candidates for radiopharmaceutical use

NASA Astrophysics Data System (ADS)

Ernestová, M.; Jedináková-Křížová, V.

2003-01-01

Reaction conditions for complexation of radionuclides with DOTA were studied using thinlayer chromatography (TLC), paper chromatography (PC) and potentiometry. It was found that all of the studied complexes can reach very high radiochemical yield about 95%. Optimal conditions for obtaining such high radiochemical yields are as follows: pH higher than 4 and the excess of chelating agent must be minimally 3∶1. Potentiometric study showed that the formation of complexes is characterised by very slow kinetics.

Radiochemical ageing of EPDM elastomers.. 2. Identification and quantification of chemical changes in EPDM and EPR films γ-irradiated under oxygen atmosphere

NASA Astrophysics Data System (ADS)

Rivaton, A.; Cambon, S.; Gardette, J.-L.

2005-01-01

This paper is devoted to the identification and quantification of the main chemical changes resulting from the radiochemical ageing under oxygen atmosphere of ethylene-propylene-diene monomer (EPDM) and ethylene-propylene rubber (EPR) films containing the same molar ratio of ethylene/propylene. IR and UV-Vis analysis showed that radiooxidation produces a complex mixture of different products and provokes the consumption of the diene double bond. The radiochemical yields of formation of ketones, carboxylic acids, hydroperoxides and alcohols were determined by combining IR analysis with derivatisation reactions and chemical titration. The contributions of secondary and tertiary structures of these two types of -OH groups were separated. Esters and γ-lactones were formed in low concentration. The oxidation products distribution in irradiated films was determined by micro-FTIR spectroscopy. Crosslinking was evaluated by gel fraction methods. In complement, the gas phase composition was analysed by mass spectrometry.

Preparation of a novel radiotracer targeting the EphB4 receptor via radiofluorination using spiro azetidinium salts as precursor.

PubMed

Wiemer, Jens; Steinbach, Jörg; Pietzsch, Jens; Mamat, Constantin

2017-08-01

The visualization of Eph receptors, which are overexpressed in various tumor entities, using selective small molecule Eph inhibitors by means of positron emission tomography is a promising approach for tumor imaging. N-(Pyrimidinyl)indazolamines represent a class of compounds, which are known to have high affinity especially for the EphB4 receptor. Radiofluorination of these compounds could provide a highly specific imaging agent and was investigated using a classical nucleophilic introduction of [ 18 F]fluoride as well as a less common nucleophilic ring-opening reaction of azetidinium salts. In the past, radiofluorinations using azetidinium precursors were demonstrated to result in high radiochemical yields in short periods. For this purpose, an azetidinium precursor based on the N-(pyrimidinyl)indazolamine lead compound was developed, and radiofluorination was successfully accomplished. The respective [ 18 F]radiotracer was quickly prepared with high radiochemical purity >97% and in a radiochemical yield of 34%. Copyright © 2017 John Wiley & Sons, Ltd.

Radiochemical and Chemical Constituents in Water from Selected Wells and Springs from the Southern Boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman Area, Idaho, 1997

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

R. C. Bartholomay; L. M. Williams; L. J. Campbell

1998-12-01

The U.S. Geological Survey and the Idaho Department of Water Resources, in cooperation with the U.S. Department of Energy, sampled 18 sites as part of the fourth round of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radiochemical and chemical constituents. The samples were collected from seven domestic wells, six irrigation wells, two springs, one dairy well, one observation well, and one stock well. Two quality-assurance samples also were collected andmore » analyzed. None of the radiochemical or chemical constituents exceeded the established maximum contaminant levels for drinking water. Many of the radionuclide- and inorganic-constituent concentrations were greater than their respective reporting levels.« less

Radiochemical and Chemical Constituents in Water from Selected Wells and Springs from the Southern Boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman Area, Idaho, 1998

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

R. C. Bartholomay; B. V. Twining; L. J. Campbell

1999-06-01

The U.S. Geological Survey and the Idaho Department of Water Resources, in cooperation with the U.S. Department of Energy, sampled 18 sites as part of the fourth round of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman area. The samples were analyzed for selected radiochemical and chemical constituents. The samples were collected from 2 domestic wells, 12 irrigation wells, 2 stock wells, 1 spring, and 1 public supply well. Two quality-assurance samples also were collected and analyzed. None of themore » reported radiochemical or chemical constituent concentrations exceeded the established maximum contaminant levels for drinking water. Many of the radionuclide- and inorganic-constituent concentrations were greater than the respective reporting levels. Most of the organic-constituent concentrations were less than the reporting levels.« less

Radiochemical and chemical constituents in water from selected wells and springs from the southern boundary of the Idaho National Laboratory to the Hagerman Area, Idaho, 2003

USGS Publications Warehouse

Rattray, Gordon W.; Wehnke, Amy J.; Hall, L. Flint; Campbell, Linford J.

2005-01-01

The U.S. Geological Survey and the Idaho Department of Water Resources, in cooperation with the U.S. Department of Energy, sampled water from 14 sites as part of an ongoing study to monitor the water quality of the eastern Snake River Plain aquifer between the southern boundary of the Idaho National Laboratory (INL) and the Burley-Twin Falls-Hagerman area. The State of Idaho, Department of Environmental Quality, Division of INL Oversight and Radiation Control cosampled with the U.S. Geological Survey and the Idaho Department of Water Resources and their analytical results are included in this report. The samples were collected from four domestic wells, two dairy wells, two springs, four irrigation wells, one observation well, and one stock well and analyzed for selected radiochemical and chemical constituents. Two quality-assurance samples, sequential replicates, also were collected and analyzed. None of the concentrations of radiochemical or organic-chemical constituents exceeded the maximum contaminant levels for drinking water established by the U.S. Environmental Protection Agency. However, the concentration of one inorganic-chemical constituent, nitrate (as nitrogen), in water from site MV-43 was 20 milligrams per liter which exceeded the maximum contaminant level for that constituent. Of the radiochemical and chemical concentrations analyzed for in the replicate-sample pairs, 267 of the 270 pairs (with 95 percent confidence) were statistically equivalent.

The Perils of Paul: Near Disasters in Airborne Radiochemical Sampling

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

Meade, Roger Allen

Beginning with the Trinity test in July 1945, Laboratory radiochemists have collected debris from nuclear tests by various means. At Trinity, two United States Army Sherman tanks were used. Beginning with Operation Crossroads and continuing throughout atmospheric testing, aircraft were used to fly in and around mushroom clouds to collect debris. Paul Guthals, the LASL project leader for sampling operations, flew on many of the B-57 sampling missions. Two such missions, one flown over the Nevada Test and one in the skies near Johnston Atoll, again proved the dangers involved in collecting airborne test debris. The events of these twomore » missions are briefly recounted.« less

Environmental 90Sr measurements

USGS Publications Warehouse

Paul, M.; Berkovits, D.; Cecil, L.D.; Feldstein, H.; Hershkowitz, A.; Kashiv, Y.; Vogt, S.

1997-01-01

90Sr (T1/2 = 28.5 years) is a long-lived radionuclide produced in nuclear fission. Fast radiochemical detection of 90Sr in environmental samples is not feasible using current analytical methods. Accelerator Mass Spectrometry (AMS) measurements of 90Sr were made with the Rehovot 14UD Pelletron accelerator at a terminal voltage of 11 or 12 MV using our standard detection system. Injection of hydride ions (SrH3-) was chosen owing to high beam intensity and low Coulomb explosion effects. 90Sr ions were identified and discriminated from isobaric 90Zr by measuring time of flight, total energy and three independent energy-loss signals in an ionization chamber. A reference sample and a ground-water sample were successfully measured. The detection limit determined for a laboratory blank by the residual counts in the 90Sr region is 90Sr/Sr = 3 ?? 10-13, corresponding in practice to (2-4) ?? 10790Sr atoms or about 0.5-1 pCi/L in environmental water samples.

Determination of uranium in tap water by ICP-MS.

PubMed

El Himri, M; Pastor, A; de la Guardia, M

2000-05-01

A fast and accurate procedure has been developed for the determination of uranium at microg L(-1) level in tap and mineral water. The method is based on the direct introduction of samples, without any chemical pre-treatment, into an inductively coupled plasma mass spectrometer (ICP-MS). Uranium was determined at the mass number 238 using Rh as internal standard. The method provides a limit of detection of 2 ng L(-1) and a good repeatability with relative standard deviation values (RSD) about 3% for five independent analyses of samples containing 73 microg L(-1) of uranium. Recovery percentage values found for the determination of uranium in spiked natural samples varied between 91% and 106%. Results obtained are comparable with those found by radiochemical methods for natural samples and of the same order for the certified content of a reference material, thus indicating the accuracy of the ICP-MS procedure without the need of using isotope dilution. A series of mineral and tap waters from different parts of Spain and Morocco were analysed.

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

Metz, Lori A.; Friese, Judah I.; Finn, Erin C.

Critical assemblies provide one method of achieving a fast neutron spectrum that is close to a 235U fission-energy neutron spectrum for nuclear data measurements. Previous work has demonstrated the use of a natural boron carbide capsule for spectral-tailoring in a mixed spectrum reactor as an alternate and complementary method for performing fission-energy neutron experiments. Previous fission products measurements showed that the neutron spectrum achievable with natural boron carbide was not as hard as what can be achieved with critical assemblies. New measurements performed with the Washington State University TRIGA reactor using a boron carbide capsule 96% enriched in 10B formore » irradiations resulted in a neutron spectrum very similar to a critical assembly and a pure 235U fission spectrum. The current work describes an experiment involving a highly-enriched uranium target irradiated under the new 10B4C capsule. Fission product yields were measured following radiochemical separations and are presented here. Reactor dosimetry measurements for characterizing neutron spectra and fluence for the enriched boron carbide capsule and critical assemblies are also discussed.« less

Sedimentological and radiochemical characteristics of marsh deposits from Assateague Island and the adjacent vicinity, Maryland and Virginia, following Hurricane Sandy

USGS Publications Warehouse

Smith, Christopher G.; Marot, Marci E.; Ellis, Alisha M.; Wheaton, Cathryn J.; Bernier, Julie C.; Adams, C. Scott

2015-09-15

This report serves as an archive for sedimentological and radiochemical data derived from the surface sediments and marsh cores collected March 26–April 4, 2014. Select surficial data are available for the additional sampling periods October 21–30, 2014. Downloadable data are available as Excel spreadsheets and as JPEG files. Additional files include: Field documentation, x-radiographs, photographs, detailed results of sediment grain size analyses, and formal Federal Geographic Data Committee metadata (data downloads).

Novel 18F-Labeled κ-Opioid Receptor Antagonist as PET Radiotracer: Synthesis and In Vivo Evaluation of 18F-LY2459989 in Nonhuman Primates.

PubMed

Li, Songye; Cai, Zhengxin; Zheng, Ming-Qiang; Holden, Daniel; Naganawa, Mika; Lin, Shu-Fei; Ropchan, Jim; Labaree, David; Kapinos, Michael; Lara-Jaime, Teresa; Navarro, Antonio; Huang, Yiyun

2018-01-01

The κ-opioid receptor (KOR) has been implicated in depression, addictions, and other central nervous system disorders and, thus, is an important target for drug development. We previously developed several 11 C-labeled PET radiotracers for KOR imaging in humans. Here we report the synthesis and evaluation of 18 F-LY2459989 as the first 18 F-labeled KOR antagonist radiotracer in nonhuman primates and its comparison with 11 C-LY2459989. Methods: The novel radioligand 18 F-LY2459989 was synthesized by 18 F displacement of a nitro group or an iodonium ylide. PET scans in rhesus monkeys were obtained on a small-animal scanner to assess the pharmacokinetic and in vivo binding properties of the ligand. Metabolite-corrected arterial activity curves were measured and used as input functions in the analysis of brain time-activity curves and the calculation of binding parameters. Results: With the iodonium ylide precursor, 18 F-LY2459989 was prepared at high radiochemical yield (36% ± 7% [mean ± SD]), radiochemical purity (>99%), and mean molar activity (1,175 GBq/μmol; n = 6). In monkeys, 18 F-LY2459989 was metabolized at a moderate rate, with a parent fraction of approximately 35% at 30 min after injection. Fast and reversible kinetics were observed, with a regional peak uptake time of less than 20 min. Pretreatment with the selective KOR antagonist LY2456302 (0.1 mg/kg) decreased the activity level in regions with high levels of binding to that in the cerebellum, thus demonstrating the binding specificity and selectivity of 18 F-LY2459989 in vivo. Regional time-activity curves were well fitted by the multilinear analysis 1 kinetic model to derive reliable estimates of regional distribution volumes. With the cerebellum as the reference region, regional binding potentials were calculated and ranked as follows: cingulate cortex > insula > caudate/putamen > frontal cortex > temporal cortex > thalamus, consistent with the reported KOR distribution in the monkey brain. Conclusion: The evaluation of 18 F-LY2459989 in nonhuman primates demonstrated many attractive imaging properties: fast tissue kinetics, specific and selective binding to the KOR, and high specific binding signals. A side-by-side comparison of 18 F-LY2459989 and 11 C-LY2459989 indicated similar kinetic and binding profiles for the 2 radiotracers. Taken together, the results indicated that 18 F-LY2459989 appears to be an excellent PET radiotracer for the imaging and quantification of the KOR in vivo. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.

The use of Whatman-31ET paper for an efficient method for radiochemical purity test of 131I-Hippuran

NASA Astrophysics Data System (ADS)

Rezka Putra, Amal; Maskur; Sugiharto, Yono; Chairuman; Hardi Gunawan, Adang; Awaludin, Rohadi

2018-01-01

Current chromatography methods used for radiochemical purity test of 131I-Hippuran is time consuming. Therefore, in this study we explored several static and mobile phases in order to have a chromatography method which is accurate and efficient or less time consuming. In this study, stationary phases (Whatman-1, 31ET, and 3MM papers) and several mobile phases were explored to separate 131I-Hippuran from its impurity (131I iodide ion). The results of this study showed that the most efficient chromatography system for measurement of radiochemical purity of 131I-Hippuran was by using Whatman-31ET paper and n-butanol: acetic acid: water (4:1:1) as a static phase and mobile phase respectively. Developing time for this method was of approximately 75.7 ± 2.7 minutes. The result of radiochemical purity (%RCP) of 131I-Hippuran measured with this chromatography system either using Whatman-1 or Whatman-31ET paper strips was 98.7%. The short size of Whatman-31ET paper strip (1 x 8 cm) was found to have shorter developing time compared to that of long size paper. This system showed a good separation of 131I-Hippuran from its impurities and gave %RCP of 98.1% ± 0.04% with developing time approximately 44.3 ± 9.4 minutes. The short size of Whatman-31ET paper strips was found to be more efficient compared to that of Whatman-1 and Whatman-3MM paper strips in term of developing time.

New spectrophotometric and radiochemical assays for acetyl-CoA: arylamine N-acetyltransferase applicable to a variety of arylamines

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

Andres, H.H.; Klem, A.J.; Szabo, S.M.

1985-03-01

Simple and sensitive spectrophotometric and radiochemical procedures are described for the assay of acetyl-CoA:arylamine N-acetyltransferase (NAT), which catalyzes the reaction acetyl-CoA + arylamine----N-acetylated arylamine + CoASH. The methods are applicable to crude tissue homogenates and blood lysates. The spectrophotometric assay is characterized by two features: (i) NAT activity is measured by quantifying the disappearance of the arylamine substrate as reflected by decreasing Schiff's base formation with dimethylaminobenzaldehyde. (ii) During the enzymatic reaction, the inhibitory product CoASH is recycled by the system acetyl phosphate/phosphotransacetylase to the substrate acetyl-CoA. The radiochemical procedure depends on enzymatic synthesis of (/sup 3/H)acetyl-CoA in the assaymore » using (/sup 3/H)acetate, ATP, CoASH, and acetyl-CoA synthetase. NAT activity is measured by quantifying N-(/sup 3/H)acetylarylamine after separation from (/sup 3/H)acetate by extraction. Product inhibition by CoASH is prevented in this system by the use of acetyl-CoA synthetase.« less

Automated radiosynthesis of no-carrier-added 4-[18F]fluoroiodobenzene: a versatile building block in 18F radiochemistry.

PubMed

Way, Jenilee Dawn; Wuest, Frank

2014-02-01

4-[18F]Fluoroiodobenzene ([18F]FIB) is a versatile building block in 18F radiochemistry used in various transition metal-mediated C-C and C-N cross-coupling reactions and [18F]fluoroarylation reactions. Various synthesis routes have been described for the preparation of [18F]FIB. However, to date, no automated synthesis of [18F]FIB has been reported to allow access to larger amounts of [18F]FIB in high radiochemical and chemical purity. Herein, we describe an automated synthesis of no-carrier-added [18F]FIB on a GE TRACERlab™ FX automated synthesis unit starting from commercially available(4-iodophenyl)diphenylsulfonium triflate as the labelling precursor. [18F]FIB was prepared in high radiochemical yields of 89 ± 10% (decay-corrected, n = 7) within 60 min, including HPLC purification. The radiochemical purity exceeded 95%, and specific activity was greater than 40 GBq/μmol. Typically, from an experiment, 6.4 GBq of [18F]FIB could be obtained starting from 10.4 GBq of [18F]fluoride.

National Biomedical Tracer Facility: Project definition study

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

Heaton, R.; Peterson, E.; Smith, P.

The Los Alamos National Laboratory is an ideal institution and New Mexico is an ideal location for siting the National Biomedical Tracer Facility (NBTF). The essence of the Los Alamos proposal is the development of two complementary irradiation facilities that combined with our existing radiochemical processing hot cell facilities and waste handling and disposal facilities provide a low cost alternative to other proposals that seek to satisfy the objectives of the NBTF. We propose the construction of a 30 MeV cyclotron facility at the site of the radiochemical facilities, and the construction of a 100 MeV target station at LAMPFmore » to satisfy the requirements and objectives of the NBTF. We do not require any modifications to our existing radiochemical processing hot cell facilities or our waste treatment and disposal facilities to accomplish the objectives of the NBTF. The total capital cost for the facility defined by the project definition study is $15.2 M. This cost estimate includes $9.9 M for the cyclotron and associated facility, $2.0 M for the 100 MeV target station at LAMPF, and $3.3 M for design.« less

Radiochemical Applications of Insoluble Sulfate Columns. Analytical Possibilities in the Field of the Fission Product Solutions; APLICACIONES RADIO-QUIMICAS DE LAS COLUMNAS DE PRECIPITADOS DE SULFATOS INSOLUBLES. CONTRIBUCION AL ESTUDIO DE LAS SOLUCIONES ENVEJECIDAS DE PRODUCTOS DE FISION

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

Barrachina, M.; Sauvagnac, R.

1962-01-01

The heterogeneous ion-isotopic exchange column is used to determine the radiochemical composition of raw solutions used in the industrial recuperation of long-lived fission products, The separation of the radioelements is made by small columns, 1--3 cm height, of BaSO/sub 4/ or SrSO/sub 4/, under selected experimental conditions. These columns behave like inorganic exchangers, working by adsorption or ion-isotopic exchange depending on the cases, and they provide selective separation of fission products employing very small volumes of fixing and eluting solutions. By coupling the separative capabilities of these columns and the liquid--liquid extraction with the 2-thenoyltrifluoroacetone and the di-2 ethylexyl orthophosphoricmore » acid, a set of new radiochemical methods, for the determination of Sr/sup 90/, Y/sup 90/, Ce/sup 144/ - Pr/sup 144/, and Pm/sup 147/ in the fission product solutions of Marcoule, were developed. (auth)« less

Assessment of the direct cyclotron production of (99m)Tc: An approach to crisis management of (99m)Tc shortage.

PubMed

Rovais, Mohammad Reza Aboudzadeh; Aardaneh, Khosro; Aslani, Gholamreza; Rahiminejad, Ali; Yousefi, Kamran; Boulouri, Fatemeh

2016-06-01

Nowadays, the cyclotron production of technetium-99m ((99m)Tc) has been increased, due to the worldwide (99m)Tc generator shortage. In the present work, an improved strategy for the production of (99m)Tc, using the proton irradiation of the enriched (100)Mo was developed. The performance of this method in terms of the production yield, chemical purity, radiochemical purity, as well as radionuclide purity was evaluated. The average production yield was measured to be 356MBqμA(-1)h(-1). A good agreement was found between the calculated production yield and the experimental one. The radiochemical separation and total recovery yields of (99m)Tc were 92% and 69%, respectively. The radiochemical and the radionuclide purities of the (99m)Tc were 99% and >99.99% at the end of purification, respectively. The results of quality control tests (QC) support the concept that cyclotron-produced (99m)Tc is suitable for preparation of USP-compliant. Copyright © 2016 Elsevier Ltd. All rights reserved.

Efficient blind search for similar-waveform earthquakes in years of continuous seismic data

NASA Astrophysics Data System (ADS)

Yoon, C. E.; Bergen, K.; Rong, K.; Elezabi, H.; Bailis, P.; Levis, P.; Beroza, G. C.

2017-12-01

Cross-correlating an earthquake waveform template with continuous seismic data has proven to be a sensitive, discriminating detector of small events missing from earthquake catalogs, but a key limitation of this approach is that it requires advance knowledge of the earthquake signals we wish to detect. To overcome this limitation, we can perform a blind search for events with similar waveforms, comparing waveforms from all possible times within the continuous data (Brown et al., 2008). However, the runtime for naive blind search scales quadratically with the duration of continuous data, making it impractical to process years of continuous data. The Fingerprint And Similarity Thresholding (FAST) detection method (Yoon et al., 2015) enables a comprehensive blind search for similar-waveform earthquakes in a fast, scalable manner by adapting data-mining techniques originally developed for audio and image search within massive databases. FAST converts seismic waveforms into compact "fingerprints", which are efficiently organized and searched within a database. In this way, FAST avoids the unnecessary comparison of dissimilar waveforms. To date, the longest duration of continuous data used for event detection with FAST was 3 months at a single station near Guy-Greenbrier, Arkansas, which revealed microearthquakes closely correlated with stages of hydraulic fracturing (Yoon et al., 2017). In this presentation we introduce an optimized, parallel version of the FAST software with improvements to the fingerprinting algorithm and the ability to detect events using continuous data from a network of stations (Bergen et al., 2016). We demonstrate its ability to detect low-magnitude earthquakes within several years of continuous data at locations of interest in California.

Energy and Water Conservation Assessment of the Radiochemical Processing Laboratory (RPL) at Pacific Northwest National Laboratory

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

Johnson, Stephanie R.; Koehler, Theresa M.; Boyd, Brian K.

2014-05-31

This report summarizes the results of an energy and water conservation assessment of the Radiochemical Processing Laboratory (RPL) at Pacific Northwest National Laboratory (PNNL). The assessment was performed in October 2013 by engineers from the PNNL Building Performance Team with the support of the dedicated RPL staff and several Facilities and Operations (F&O) department engineers. The assessment was completed for the Facilities and Operations (F&O) department at PNNL in support of the requirements within Section 432 of the Energy Independence and Security Act (EISA) of 2007.

QUANTITATIVE RADIO-CHEMICAL ANALYSIS-SOLVENT EXTRACTION OF MOLYBDENUM-99

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

Wish, L.

1961-09-12

A method was developed for the rapid quantitative separation of Mo/sup 99/ from fission product mixtures. It is based on the extraction of Mo into a solution of alpha -benzoin oxime in chloroform. The main contaminants are Zr, Nb, and 1. The first two are eliminated by couple with fluoride and the third by volatilization or solvent extraction. About 5% of the Te/sup 99/ daughter is extracted with its parent, and it is necessary to wait 48 hrs for equilibrium of fission product mixtures by this method and a standard radiochemical gravimetric procedure showed agreement within 1 to 2%. (auth)

Focusing light through dynamical samples using fast continuous wavefront optimization.

PubMed

Blochet, B; Bourdieu, L; Gigan, S

2017-12-01

We describe a fast continuous optimization wavefront shaping system able to focus light through dynamic scattering media. A micro-electro-mechanical system-based spatial light modulator, a fast photodetector, and field programmable gate array electronics are combined to implement a continuous optimization of a wavefront with a single-mode optimization rate of 4.1 kHz. The system performances are demonstrated by focusing light through colloidal solutions of TiO 2 particles in glycerol with tunable temporal stability.

A Computer Model of the Evaporator for the Development of an Automatic Control System

NASA Astrophysics Data System (ADS)

Kozin, K. A.; Efremov, E. V.; Kabrysheva, O. P.; Grachev, M. I.

2016-08-01

For the implementation of a closed nuclear fuel cycle it is necessary to carry out a series of experimental studies to justify the choice of technology. In addition, the operation of the radiochemical plant is impossible without high-quality automatic control systems. In the technologies of spent nuclear fuel reprocessing, the method of continuous evaporation is often used for a solution conditioning. Therefore, the effective continuous technological process will depend on the operation of the evaporation equipment. Its essential difference from similar devices is a small size. In this paper the method of mathematic simulation is applied for the investigation of one-effect evaporator with an external heating chamber. Detailed modelling is quite difficult because the phase equilibrium dynamics of the evaporation process is not described. Moreover, there is a relationship with the other process units. The results proved that the study subject is a MIMO plant, nonlinear over separate control channels and not selfbalancing. Adequacy was tested using the experimental data obtained at the laboratory evaporation unit.

Obesity, fast food manufacture, and regulation: revisiting opportunities for reform.

PubMed

Ahmed, Haitham M

2009-01-01

Regulations have historically been able to shape public behavior in various ways. As poor dietary practices and obesity continue to pose major health and economic threats to society, attention will continue to be directed towards the ethical and legal responsibilities of fast food manufacturers as potential contributors to these problems. In light of these considerations, several opportunities emerge that may impact dietary behavior and obesity through regulation of the fast food industry. This article addresses the health consequences of fast food consumption, as well as the historical and legal contexts of fast food regulation in the United States.

SPECTROSCOPIC ONLINE MONITORING FOR PROCESS CONTROL AND SAFEGUARDING OF RADIOCHEMICAL STREAMS

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

Bryan, Samuel A.; Levitskaia, Tatiana G.

2013-09-29

There is a renewed interest worldwide to promote the use of nuclear power and close the nuclear fuel cycle. The long term successful use of nuclear power is critically dependent upon adequate and safe processing and disposition of the used nuclear fuel. Liquid-liquid extraction is a separation technique commonly employed for the processing of the dissolved used nuclear fuel. The instrumentation used to monitor these processes must be robust, require little or no maintenance, and be able to withstand harsh environments such as high radiation fields and aggressive chemical matrices. This paper summarizes application of the absorption and vibrational spectroscopicmore » techniques supplemented by physicochemical measurements for radiochemical process monitoring. In this context, our team experimentally assessed the potential of Raman and spectrophotometric techniques for online real-time monitoring of the U(VI)/nitrate ion/nitric acid and Pu(IV)/Np(V)/Nd(III), respectively, in solutions relevant to spent fuel reprocessing. These techniques demonstrate robust performance in the repetitive batch measurements of each analyte in a wide concentration range using simulant and commercial dissolved spent fuel solutions. Spectroscopic measurements served as training sets for the multivariate data analysis to obtain partial least squares predictive models, which were validated using on-line centrifugal contactor extraction tests. Satisfactory prediction of the analytes concentrations in these preliminary experiments warrants further development of the spectroscopy-based methods for radiochemical process control and safeguarding. Additionally, the ability to identify material intentionally diverted from a liquid-liquid extraction contactor system was successfully tested using on-line process monitoring as a means to detect the amount of material diverted. A chemical diversion and detection from a liquid-liquid extraction scheme was demonstrated using a centrifugal contactor system operating with the simulant PUREX extraction system of Nd(NO3)3/nitric acid aqueous phase and TBP/n-dodecane organic phase. During a continuous extraction experiment, a portion of the feed from a counter-current extraction system was diverted while the spectroscopic on-line process monitoring system was simultaneously measuring the feed, raffinate and organic products streams. The amount observed to be diverted by on-line spectroscopic process monitoring was in excellent agreement with values based from the known mass of sample directly taken (diverted) from system feed solution.« less

Harvesting (67)Cu from the Collection of a Secondary Beam Cocktail at the National Superconducting Cyclotron Laboratory.

PubMed

Mastren, Tara; Pen, Aranh; Loveless, Shaun; Marquez, Bernadette V; Bollinger, Elizabeth; Marois, Boone; Hubley, Nicholas; Brown, Kyle; Morrissey, David J; Peaslee, Graham F; Lapi, Suzanne E

2015-10-20

Isotope harvesting is a promising new method to obtain isotopes for which there is no reliable continuous supply at present. To determine the possibility of obtaining radiochemically pure radioisotopes from an aqueous beam dump at a heavy-ion fragmentation facility, preliminary experiments were performed to chemically extract a copper isotope from a large mixture of projectile fragmentation products in an aqueous medium. In this work a 93 MeV/u secondary beam cocktail was collected in an aqueous beam stop at the National Superconducting Cyclotron Laboratory (NSCL) located on the Michigan State University (MSU) campus. The beam cocktail consisted of ∼2.9% (67)Cu in a large mixture of co-produced isotopes ranging in atomic number from ∼19 to 34. The chemical extraction of (67)Cu was achieved via a two-step process: primary extraction using a divalent metal chelation disk followed by anion-exchange chromatography. A significant fraction (74 ± 4%) of the (67)Cu collected in the aqueous beam stop was recovered with >99% radiochemical purity. To illustrate the utility of this product, the purified (67)Cu material was then used to radiolabel an anti-EGFR antibody, Panitumumab, and injected into mice bearing colon cancer xenografts. The tumor uptake at 5 days postinjection was found to be 12.5 ± 0.7% which was in very good agreement with previously reported studies with this radiolabeled antibody. The present results demonstrate that harvesting isotopes from a heavy-ion fragmentation facility could be a promising new method for obtaining high-quality isotopes that are not currently available by traditional methods.

Design and performance of an automated radionuclide separator: its application on the determination of ⁹⁹Tc in groundwater.

PubMed

Chung, Kun Ho; Choi, Sang Do; Choi, Geun Sik; Kang, Mun Ja

2013-11-01

A modular automated radionuclide separator for (99)Tc (MARS Tc-99) has been developed for the rapid and reproducible separation of technetium in groundwater samples. The control software of MARS Tc-99 was developed in the LabView programming language. An automated radiochemical method for separating (99)Tc was developed and validated by the purification of (99m)Tc tracer solution eluted from a commercial (99)Mo/(99m)Tc generator. The chemical recovery and analytical time for this radiochemical method were found to be 96 ± 2% and 81 min, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

THE EFFECT OF SELF- AND EXTERNAL RADIATIONS ON I$sup 131$-LABELLED 1- THYROXINE AND 3,5,3'-TRIIODO-1-THYRONINE IN SOLUTION

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

Tata, J.R.

1959-05-01

Chemical changes produced in dilute solutions of I/sup 131/labeled l- thyroxine and 3,5,3'-triiodo-l-thyronine by the action of self- and external radiations (high energy x and radiation) have been studied quantitatively. The same major products of radiochemical decomposition, Compounds "1" and "2", were obtained from selfradiation in labeled thyroxine and triiodothyronine of high specific activity and from externally irradiated samples of low specific activity. By a combination of chromatographic, electrophoretic and spot-test analyses, Compound "1" has been tentatively identified as gestion for the formation of a similar derivative of triiodothyronine. The kinetics of radiochemical change induced by self-radiation of the twomore » iodothyronines have been studied over a period of storage of 40 days. Once formed, the lactic acid analogues of the hormones are rapidly deiodinated. The radiochemical reaction is inhibited by storage in the dried or frozen state or by the addition of cysteines glycine and human serum albumin. The possible mechanism of the radiationinduced changes and their implications in biological work are discussed. (auth)« less

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

Pavelka, M.; Gangl, A.

The involvement of microtubules in the transepithelial transport of exogenous lipid in intestinal absorptive cells has been suggested. Using electronmicroscopic, biochemical, and radiochemical methods, researchers have studied the effects of the antimicrotubular agent colchicine on the intestinal mucosa and on the intestinal transport of endogenous lipid of rats in the fasting state. After colchicine treatment, the concentration of triglycerides in intestinal mucosa of rats fasted for 24 h doubled, and electron microscopic studies showed a striking accumulation of lipid particles in absorptive epithelial cells of the tips of jejunal villi. These findings suggest that colchicine interferes with the intestinal transepithelialmore » transport of endogenous lipoproteins. Additional studies, using an intraduodenal pulse injection of (/sup 14/C)linoleic acid, showed that colchicine does not affect the uptake of fatty acids by intestinal mucosa. However, it had divergent effects on fatty acid esterification, enhancing their incorporation into triglycerides relative to phospholipids, and caused a significant accumulation of endogenous diglycerides, triglycerides, and cholesterol esters within the absorptive intestinal epithelium. Detailed ultrastructural and morphometric studies revealed a decrease of visible microtubules, and a displacement of the smooth and rough endoplasmic reticulum and Golgi apparatus. Furthermore, it is shown that after colchicine treatment, microvilli appear at the lateral plasma membrane of intestinal absorptive cells, a change not previously reported to our knowledge. Thus, our study shows that colchicine causes significant changes in enterocyte ultrastructure and colchicine perturbs the reesterification of absorbed endogenous fatty acids and their secretion in the form of triglyceride-rich lipoproteins from the enterocyte.« less

Radiochemical determination of 241Am and Pu(alpha) in environmental materials.

PubMed

Warwick, P E; Croudace, I W; Oh, J S

2001-07-15

Americium-241 and plutonium determinations will become of greater importance over the coming decades as 137Cs and 241Pu decay. The impact of 137Cs on environmental chronology has been great, but its potency is waning as it decays and diffuses. Having 241Am and Pu as unequivocal markers for the 1963 weapon fallout maximum is important for short time scale environmental work, but a fast and reliable procedure is required for their separation. The developed method described here begins by digesting samples using a lithium borate fusion although an aqua regia leachate is also effective in many instances. Isolation of the Am and Pu is then achieved using a combination of extraction chromatography and conventional anion exchange chromatography. The whole procedure has been optimized, validated, and assessed for safety. The straightforwardness of this technique permits the analysis of large numbers of samples and makes 241Am-based techniques for high-resolution sediment accumulation rate studies attractive. In addition, the technique can be employed for the sequential measurement of Pu and Am in environmental surveillance programs, potentially reducing analytical costs and turnround times.

Continuous-Flow Synthesis of N-Succinimidyl 4-[18F]fluorobenzoate Using a Single Microfluidic Chip

PubMed Central

Kimura, Hiroyuki; Tomatsu, Kenji; Saiki, Hidekazu; Arimitsu, Kenji; Ono, Masahiro; Kawashima, Hidekazu; Iwata, Ren; Nakanishi, Hiroaki; Ozeki, Eiichi; Kuge, Yuji; Saji, Hideo

2016-01-01

In the field of positron emission tomography (PET) radiochemistry, compact microreactors provide reliable and reproducible synthesis methods that reduce the use of expensive precursors for radiolabeling and make effective use of the limited space in a hot cell. To develop more compact microreactors for radiosynthesis of 18F-labeled compounds required for the multistep procedure, we attempted radiosynthesis of N-succinimidyl 4-[18F]fluorobenzoate ([18F]SFB) via a three-step procedure using a microreactor. We examined individual steps for [18F]SFB using a batch reactor and microreactor and developed a new continuous-flow synthetic method with a single microfluidic chip to achieve rapid and efficient radiosynthesis of [18F]SFB. In the synthesis of [18F]SFB using this continuous-flow method, the three-step reaction was successfully completed within 6.5 min and the radiochemical yield was 64 ± 2% (n = 5). In addition, it was shown that the quality of [18F]SFB synthesized on this method was equal to that synthesized by conventional methods using a batch reactor in the radiolabeling of bovine serum albumin with [18F]SFB. PMID:27410684

Radiochemical techniques for determining some naturally occurring radionuclides in marine environmental materials

NASA Astrophysics Data System (ADS)

Baker, C. W.

1984-06-01

The determination of some of the naturally-occurring, alpha-emitting radionuclides in marine environmental materials, is of interest for several reasons. Radium and radon nuclides are potentially useful as oceanographic tracers. Lead and thorium nuclides may be used to study sedimentation rates, mixing processes and bioturbation in sediments. Radium and polonium nuclides are incorporated into food chains and the data may provide a perspective against which to assess the significance, for marine organisms, of exposure to radiation in a marine radioactive waste disposal situation. This paper discusses the manner in which samples are taken, and the radiochemical methods which have been employed to measure the nuclides, together with some data produced.

General method for labeling siRNA by click chemistry with fluorine-18 for the purpose of PET imaging.

PubMed

Mercier, Frédéric; Paris, Jérôme; Kaisin, Geoffroy; Thonon, David; Flagothier, Jessica; Teller, Nathalie; Lemaire, Christian; Luxen, André

2011-01-19

The alkyne-azide Cu(I)-catalyzed Huisgen cycloaddition, a click-type reaction, was used to label a double-stranded oligonucleotide (siRNA) with fluorine-18. An alkyne solid support CPG for the preparation of monostranded oligonucleotides functionalized with alkyne has been developed. Two complementary azide labeling agents (1-(azidomethyl)-4-[(18)F]fluorobenzene) and 1-azido-4-(3-[(18)F]fluoropropoxy)benzene have been produced with 41% and 35% radiochemical yields (decay-corrected), respectively. After annealing with the complementary strand, the siRNA was directly labeled by click chemistry with [(18)F]fluoroazide to produce the [(18)F]-radiolabeled siRNA with excellent radiochemical yield and purity.

Fallout from Nuclear Cratering Shot DANNY BOY. I. Radiochemical Analysis and Some Physical Observations on Selected Samples

DTIC Science & Technology

1980-02-01

radiochemical procedures described in Appendix A. All results were reported in terms of the number of u035 thermal- neutron fissions which would have produced...Ca, Mg, Al, Si, and Fe, expressed both as elements and as oxides . The last column shows the sum of the oxides . The deviation of t~pse values from 100...4.4 Cs13 6 12.9 0.0537 0.006 9.71 y 10’ 7.14 y i0ř 5.9 Ba140 12.79 0.0542 6.3 Ce 3.5 0.0213 6.0 6Ce 52 o.OQ h 6 6.1 a. For ther-a!- neutron fission

Radiochemical synthesis of a carbon-supported Pt-SnO2 bicomponent nanostructure exhibiting enhanced catalysis of ethanol oxidation

NASA Astrophysics Data System (ADS)

Okazaki, Tomohisa; Seino, Satoshi; Nakagawa, Takashi; Kugai, Junichiro; Ohkubo, Yuji; Akita, Tomoki; Nitani, Hiroaki; Yamamoto, Takao A.

2015-03-01

Carbon-supported Pt-SnO2 electrocatalysts with various Sn/Pt molar ratios were prepared by an electron beam irradiation method. These catalysts were composed of metallic Pt particles approximately 5 nm in diameter together with low crystalline SnO2. The contact between the Pt and SnO2 in these materials varied with the amount of dissolved oxygen in the precursor solutions and it was determined that intimate contact between the Pt and SnO2 significantly enhanced the catalytic activity of these materials during the ethanol oxidation reaction. The mechanism by which the contact varies is discussed based on the radiochemical reduction process.

Note: Radiochemical measurement of fuel and ablator areal densities in cryogenic implosions at the National Ignition Facility

NASA Astrophysics Data System (ADS)

Hagmann, C.; Shaughnessy, D. A.; Moody, K. J.; Grant, P. M.; Gharibyan, N.; Gostic, J. M.; Wooddy, P. T.; Torretto, P. C.; Bandong, B. B.; Bionta, R.; Cerjan, C. J.; Bernstein, L. A.; Caggiano, J. A.; Herrmann, H. W.; Knauer, J. P.; Sayre, D. B.; Schneider, D. H.; Henry, E. A.; Fortner, R. J.

2015-07-01

A new radiochemical method for determining deuterium-tritium (DT) fuel and plastic ablator (CH) areal densities (ρR) in high-convergence, cryogenic inertial confinement fusion implosions at the National Ignition Facility is described. It is based on measuring the 198Au/196Au activation ratio using the collected post-shot debris of the Au hohlraum. The Au ratio combined with the independently measured neutron down scatter ratio uniquely determines the areal densities ρR(DT) and ρR(CH) during burn in the context of a simple 1-dimensional capsule model. The results show larger than expected ρR(CH) values, hinting at the presence of cold fuel-ablator mix.

Combined radiochemical procedure for determination of plutonium, americium and strontium-90 in the soil samples from SNTS

NASA Astrophysics Data System (ADS)

Kazachevskii, I. V.; Lukashenko, S. N.; Chumikov, G. N.; Chakrova, E. T.; Smirin, L. N.; Solodukhin, V. P.; Khayekber, S.; Berdinova, N. M.; Ryazanova, L. A.; Bannyh, V. I.; Muratova, V. M.

1999-01-01

The results of combined radiochemical procedure for the determination of plutonium, americium and90Sr (via measurement of90Y) in the soil samples from SNTS are presented. The processes of co-precipitation of these nuclides with calcium fluoride in the strong acid solutions have been investigated. The conditions for simultaneous separation of americium and yttrium using extraction chromatography have been studied. It follows from analyses of real soil samples that the procedure developed provides the chemical recovery of plutonium and yttrium in the range of 50-95% and 60-95%, respectively. The execution of the procedure requires 3.5 working days including a sample decomposition study.

Ustur whole body case 0269: demonstrating effectiveness of i.v. CA-DTPA for Pu.

PubMed

James, A C; Sasser, L B; Stuit, D B; Glover, S E; Carbaugh, E H

2007-01-01

This whole body donation case (USTUR Registrant) involved a single acute inhalation of an acidic Pu(NO3)4 solution in the form of an aerosol 'mist'. Chelation treatment with intravenously (i.v.) Ca-EDTA was initiated on the day of the intake, and continued intermittently over 6 months. After 2.5 y with no further treatment, a course of i.v. Ca-DTPA was administered. A total of 400 measurements of 239+240Pu excreted in urine were recorded; starting on the first day (both before and during the initial Ca-EDTA chelation) and continuing for 37 y. This sampling included all intervals of chelation. In addition, 91 measurements of 239+240Pu-in-feces were recorded over this whole period. The Registrant died about 38 y after the intake, at age 79 y, with extensive carcinomatosis secondary to adenocarcinoma of the prostate gland. At autopsy, all major soft tissue organs were harvested for radiochemical analyses of their 238Pu, 239+240Pu and 241Am content. Also, all types of bone (comprising about half the skeleton) were harvested for radiochemical analyses, as well as samples of skin, subcutaneous fat and muscle. This comprehensive data set has been applied to derive 'chelation-enhanced' transfer rates in the ICRP Publication 67 plutonium biokinetic model, representing the behaviour of blood-borne and tissue-incorporated plutonium during intervals of therapy. The resulting model of the separate effects of i.v. Ca-EDTA and Ca-DTPA chelation shows that the therapy administered in this case succeeded in reducing substantially the long-term burden of plutonium in all body organs, except for the lungs. The calculated reductions in organ content at the time of death are approximately 40% for the liver, 60% for other soft tissues (muscle, skin, glands, etc.), 50% for the kidneys and 50% for the skeleton. Essentially, all of the substantial reduction in skeletal burden occurred in trabecular bone. This modelling exercise demonstrated that 3-y-delayed Ca-DTPA therapy was as effective as promptly administered Ca-EDTA.

USTUR WHOLE BODY CASE 0269: DEMONSTRATING EFFECTIVENESS OF I.V. CA-DTPA FOR PU

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

James, Anthony C.; Sasser , Lyle B.; Stuit, Dorothy B.

2008-01-28

This whole body donation case (USTUR Registrant) involved a single acute inhalation of an acidic Pu(NO3)4 solution in the form of an aerosol ‘mist.’ Chelation treatment with i.v. Ca-EDTA was initiated on the day of the intake, and continued intermittently over 6 months. After 2½ years with no further treatment, a course of i.v. Ca-DTPA was administered. A total of 400 measurements of 239+240Pu excreted in urine were recorded; starting on the first day (both before and during the initial Ca-EDTA chelation), and continuing for 37 years. This sampling included all intervals of chelation. In addition, 91 measurements of 239+240Pu-in-fecesmore » were recorded over this whole period. The Registrant died about 38 years after the intake, at age 79 y, with extensive carcinomatosis secondary to adenocarcinoma of the prostate gland. At autopsy, all major soft tissue organs were harvested for radiochemical analyses of their 238Pu, 239+240Pu and 241Am content. Also, all types of bone (comprising about half the skeleton) were harvested for radiochemical analyses, as well as samples of skin, subcutaneous fat and muscle. This comprehensive dataset has been applied to derive ‘chelation-enhanced’ transfer rates in the ICRP Publication 67 plutonium biokinetic model, representing the behaviour of blood-borne and tissue-incorporated plutonium during intervals of therapy. The resulting model of the separate effects of i.v. Ca-EDTA and Ca-DTPA chelation shows that the therapy administered in this case succeeded in reducing substantially the long-term burden of plutonium in all body organs, except for the lungs. The calculated reductions in organ content at the time of death are approximately 40% for the liver, 60% for other soft tissues (muscle, skin, glands, etc.), 50% for the kidneys, and 50% for the skeleton. Essentially all of the substantial reduction in skeletal burden occurred in trabecular bone. This modeling exercise demonstrated that 3-y-delayed Ca-DTPA therapy was as effective as promptly administered Ca-EDTA.« less

Automated synthesis of N-(2-[18 F]Fluoropropionyl)-l-glutamic acid as an amino acid tracer for tumor imaging on a modified [18 F]FDG synthesis module.

PubMed

Liu, Shaoyu; Sun, Aixia; Zhang, Zhanwen; Tang, Xiaolan; Nie, Dahong; Ma, Hui; Jiang, Shende; Tang, Ganghua

2017-06-15

N-(2-[ 18 F]Fluoropropionyl)-l-glutamic acid ([ 18 F]FPGLU) is a potential amino acid tracer for tumor imaging with positron emission tomography. However, due to the complicated multistep synthesis, the routine production of [ 18 F]FPGLU presents many challenging laboratory requirements. To simplify the synthesis process of this interesting radiopharmaceutical, an efficient automated synthesis of [ 18 F]FPGLU was performed on a modified commercial fluorodeoxyglucose synthesizer via a 2-step on-column hydrolysis procedure, including 18 F-fluorination and on-column hydrolysis reaction. [ 18 F]FPGLU was synthesized in 12 ± 2% (n = 10, uncorrected) radiochemical yield based on [ 18 F]fluoride using the tosylated precursor 2. The radiochemical purity was ≥98%, and the overall synthesis time was 35 minutes. To further optimize the radiosynthesis conditions of [ 18 F]FPGLU, a brominated precursor 3 was also used for the preparation of [ 18 F]FPGLU, and the improved radiochemical yield was up to 20 ± 3% (n = 10, uncorrected) in 35 minutes. Moreover, all these results were achieved using the similar on-column hydrolysis procedure on the modified fluorodeoxyglucose synthesis module. Copyright © 2017 John Wiley & Sons, Ltd.

Synthesis of [11C]Am80 via Novel Pd(0)-Mediated Rapid [11C]Carbonylation Using Arylboronate and [11C]Carbon Monoxide

PubMed Central

2012-01-01

11C-labeled methylbenzoates [11C]4a–d were synthesized using Pd(0)-mediated rapid cross-coupling reactions employing [11C]carbon monoxide and arylboronic acid neopentyl glycol esters 3a–d under atmospheric pressure in methanol–dimethylformamide (MeOH–DMF), in radiochemical yields of 12 ± 5–26 ± 13% (decay-corrected based on [11C]O). The reaction conditions were highly favorable for the synthesis of [11C]Am80 ([11C]2) and [11C]methyl 4-((5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)carbamoyl)benzoate ([11C]2-Me) using 4-(5,5-dimethyl-1,3,2-dioxaborinan-2-yl)-N-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)benzamide (5), both of which produced a decay-corrected radiochemical yield (RCY) of 26 ± 13%, with >99% radiochemical purity and an average specific radioactivity of 44 GBq/μmol. The yields of [11C]4a, [11C]2-Me, and [11C]2 were improved by the use of a 2-fold excess of the solvents and reagents under the same conditions to give respective yields of 66 ± 8, 65 ± 7, and 48 ± 2%. PMID:24900383

Synthesis of [(11)C]Am80 via Novel Pd(0)-Mediated Rapid [(11)C]Carbonylation Using Arylboronate and [(11)C]Carbon Monoxide.

PubMed

Takashima-Hirano, Misato; Ishii, Hideki; Suzuki, Masaaki

2012-10-11

(11)C-labeled methylbenzoates [(11)C]4a-d were synthesized using Pd(0)-mediated rapid cross-coupling reactions employing [(11)C]carbon monoxide and arylboronic acid neopentyl glycol esters 3a-d under atmospheric pressure in methanol-dimethylformamide (MeOH-DMF), in radiochemical yields of 12 ± 5-26 ± 13% (decay-corrected based on [(11)C]O). The reaction conditions were highly favorable for the synthesis of [(11)C]Am80 ([(11)C]2) and [(11)C]methyl 4-((5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)carbamoyl)benzoate ([(11)C]2-Me) using 4-(5,5-dimethyl-1,3,2-dioxaborinan-2-yl)-N-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)benzamide (5), both of which produced a decay-corrected radiochemical yield (RCY) of 26 ± 13%, with >99% radiochemical purity and an average specific radioactivity of 44 GBq/μmol. The yields of [(11)C]4a, [(11)C]2-Me, and [(11)C]2 were improved by the use of a 2-fold excess of the solvents and reagents under the same conditions to give respective yields of 66 ± 8, 65 ± 7, and 48 ± 2%.

Radiochemical and Chemical Constituents in Water from Selected Wells and Springs from the Southern Boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman Area, Idaho, 2002

USGS Publications Warehouse

Rattray, Gordon W.; Campbell, Linford J.

2004-01-01

The U.S. Geological Survey, Idaho Department of Water Resources, and the State of Idaho INEEL Oversight Program, in cooperation with the U.S. Department of Energy, sampled water from 17 sites as part of the sixth round of a long-term project to monitor water quality of the eastern Snake River Plain aquifer from the southern boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman area. The samples were collected from eight irrigation wells, three domestic wells, one stock well, one dairy well, one commercial well, one observation well, and two springs and analyzed for selected radiochemical and chemical constituents. One quality-assurance sample, a sequential replicate, also was collected and analyzed. Many of the radionuclide and inorganic-constituent concentrations were greater than the reporting levels and most of the organic-constituent concentrations were less than the reporting levels. However, none of the reported radiochemical- or chemical-constituent concentrations exceeded the maximum contaminant levels for drinking water established by the U.S. Environmental Protection Agency. Statistical evaluation of the replicate sample pair indicated that, with 95 percent confidence, 132 of the 135 constituent concentrations of the replicate pair were equivalent.

Radiochemical analysis of waters and mud of Euganean spas (Padua)

NASA Astrophysics Data System (ADS)

Cantaluppi, C.; Fasson, A.; Ceccotto, F.; Cianchi, A.; Degetto, S.

2012-04-01

The area around the Euganean Hills (North-East Italy) is concerned with thermal phenomena known and used for therapeutic purposes since ancient times. The thermal waters collected in this area have taken up a natural radionuclides content due to the leaching of hot and permeable deep rocks, with which they come into contact, before their rising to the surface. During the "maturation" process of the mud used for treatment purposes, the thermal waters make happen a complex series of biochemical changes and release a series of chemical species to the mud, resulting, in particular, in an enrichment phenomenon for some radionuclides. In this work, the first radiochemical analysis extended to all the Euganean Thermal District is reported. In particular, chemical analyses of mud, as well as radiochemical analyses of both mud and waters were performed; the enrichment of the radioisotopes in mud used for treatments was also documented. The results show that the 226Ra content in mud, during the "maturation" process, presents an enrichment even of one order of magnitude with respect to the value found in the unprocessed mud. Furthermore, in the same thermal waters, high concentrations of "unsupported" 222Rn have been found, which have shown to be not completely negligible both for people under treatment and particularly for spa workers.

A novel radiochemical approach to 1-(2'-deoxy-2'-[(18) F]fluoro-β-d-arabinofuranosyl)cytosine ((18) F-FAC).

PubMed

Meyer, Jan-Philip; Probst, Katrin C; Trist, Iuni M L; McGuigan, Christopher; Westwell, Andrew D

2014-09-01

(18) F-FAC (1-(2'-deoxy-2'-[(18) F]fluoro-β-D-arabinofuranosyl)-cytosine) is an important 2'-fluoro-nucleoside-based positron emission tomography (PET) tracer that has been used for in vivo prediction of response to the widely used cancer chemotherapy drug gemcitabine. Previously reported synthetic routes to (18) F-FAC have relied on early introduction of the (18) F radiolabel prior to attachment to protected cytosine base. Considering the (18) F radiochemical half-life (110 min) and the technical challenges of multi-step syntheses on PET radiochemistry modular systems, late-stage radiofluorination is preferred for reproducible and reliable radiosynthesis with in vivo applications. Herein, we report the first late-stage radiosynthesis of (18) F-FAC. Cytidine derivatives with leaving groups at the 2'-position are particularly prone to undergo anhydro side-product formation upon heating because of their electron density at the 2-carbonyl pyrimidone oxygen. Our rationally developed fluorination precursor showed an improved reactivity-to-stability ratio at elevated temperatures. (18) F-FAC was obtained in radiochemical yields of 4.3-5.5% (n = 8, decay-corrected from end of bombardment), with purities ≥98% and specific activities ≥63 GBq/µmol. The synthesis time was 168 min. Copyright © 2014 John Wiley & Sons, Ltd.

Radiochemical determination of 237NP in soil samples contaminated with weapon grade plutonium

NASA Astrophysics Data System (ADS)

Antón, M. P.; Espinosa, A.; Aragón, A.

2006-01-01

The Palomares terrestrial ecosystem (Spain) constitutes a natural laboratory to study transuranics. This scenario is partially contaminated with weapon-grade plutonium since the burnout and fragmentation of two thermonuclear bombs accidentally dropped in 1966. While performing radiometric measurements in the field, the possible presence of 237Np was observed through its 29 keV gamma emission. To accomplish a detailed characterization of the source term in the contaminated area using the isotopic ratios Pu-Am-Np, the radiochemical isolation and quantification by alpha spectrometry of 237Np was initiated. The selected radiochemical procedure involves separation of Np from Am, U and Pu with ionic resins, given that in soil samples from Palomares 239+240Pu levels are several orders of magnitude higher than 237Np. Then neptunium is isolated using TEVA organic resins. After electrodeposition, quantification is performed by alpha spectrometry. Different tests were done with blank solutions spiked with 236Pu and 237Np, solutions resulting from the total dissolution of radioactive particles and soil samples. Results indicate that the optimal sequential radionuclide separation order is Pu-Np, with decontamination percentages obtained with the ionic resins ranging from 98% to 100%. Also, the addition of NaNO2 has proved to be necessary, acting as a stabilizer of Pu-Np valences.

40 CFR 72.82 - Fast-track modifications.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Fast-track modifications. 72.82... (CONTINUED) PERMITS REGULATION Permit Revisions § 72.82 Fast-track modifications. The following procedures shall apply to all fast-track modifications. (a) If the Administrator is the permitting authority, the...

40 CFR 72.82 - Fast-track modifications.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Fast-track modifications. 72.82... (CONTINUED) PERMITS REGULATION Permit Revisions § 72.82 Fast-track modifications. The following procedures shall apply to all fast-track modifications. (a) If the Administrator is the permitting authority, the...

40 CFR 72.82 - Fast-track modifications.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Fast-track modifications. 72.82... (CONTINUED) PERMITS REGULATION Permit Revisions § 72.82 Fast-track modifications. The following procedures shall apply to all fast-track modifications. (a) If the Administrator is the permitting authority, the...

40 CFR 72.82 - Fast-track modifications.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Fast-track modifications. 72.82... (CONTINUED) PERMITS REGULATION Permit Revisions § 72.82 Fast-track modifications. The following procedures shall apply to all fast-track modifications. (a) If the Administrator is the permitting authority, the...

40 CFR 72.82 - Fast-track modifications.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Fast-track modifications. 72.82... (CONTINUED) PERMITS REGULATION Permit Revisions § 72.82 Fast-track modifications. The following procedures shall apply to all fast-track modifications. (a) If the Administrator is the permitting authority, the...

Rapid determination of 226Ra in environmental samples

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

Maxwell, Sherrod L.; Culligan, Brian K.

A new rapid method for the determination of {sup 228}Ra in natural water samples has been developed at the SRNL/EBL (Savannah River National Lab/ Environmental Bioassay Laboratory) that can be used for emergency response or routine samples. While gamma spectrometry can be employed with sufficient detection limits to determine {sup 228}Ra in solid samples (via {sup 228}Ac) , radiochemical methods that employ gas flow proportional counting techniques typically provide lower MDA (Minimal Detectable Activity) levels for the determination of {sup 228}Ra in water samples. Most radiochemical methods for {sup 228}Ra collect and purify {sup 228}Ra and allow for {sup 228}Acmore » daughter ingrowth for ~36 hours. In this new SRNL/EBL approach, {sup 228}Ac is collected and purified from the water sample without waiting to eliminate this delay. The sample preparation requires only about 4 hours so that {sup 228}Ra assay results on water samples can be achieved in < 6 hours. The method uses a rapid calcium carbonate precipitation enhanced with a small amount of phosphate added to enhance chemical yields (typically >90%), followed by rapid cation exchange removal of calcium. Lead, bismuth, uranium, thorium and protactinium isotopes are also removed by the cation exchange separation. {sup 228}Ac is eluted from the cation resin directly onto a DGA Resin cartridge attached to the bottom of the cation column to purify {sup 228}Ac. DGA Resin also removes lead and bismuth isotopes, along with Sr isotopes and {sup 90}Y. La is used to determine {sup 228}Ac chemical yield via ICP-MS, but {sup 133}Ba can also be used instead if ICP-MS assay is not available. Unlike some older methods, no lead or strontium holdback carriers or continual readjustment of sample pH is required.« less

Novel (188)Re multi-functional bone-seeking compounds: Synthesis, biological and radiotoxic effects in metastatic breast cancer cells.

PubMed

Fernandes, Célia; Monteiro, Sofia; Belchior, Ana; Marques, Fernanda; Gano, Lurdes; Correia, João D G; Santos, Isabel

2016-02-01

Radiolabeled bisphosphonates (BPs) have been used for bone imaging and delivery of β(-) emitting radionuclides for bone pain palliation. As a β(-) emitter, (188)Re has been considered particularly promising for bone metastases therapy. Aimed at finding innovative bone-seeking agents for systemic radiotherapy of bone metastases, we describe herein novel organometallic compounds of the type fac-[(188)Re(CO)3(k(3)-L)], (L=BP-containing chelator), their in vitro and in vivo stability, and their cellular damage in MDAMB231 cells, a metastatic breast cancer cell line. After synthesis and characterization of the novel organometallic compounds of the type fac-[(188)Re(CO)3(k(3)-L)] their radiochemical purity and in vitro stability was assessed by HPLC. In vivo stability and pharmacokinetic profile were evaluated in mice and the radiocytotoxic activity and DNA damage were assessed by MTT assay and by the cytokinesis-block micronucleus (CBMN) assay, respectively. Among all complexes, (188)Re3 was obtained with high radiochemical purity (>95%) and high specific activity and presented high in vitro and in vivo stability. Biodistribution studies of (188)Re3 in Balb/c mice showed fast blood clearance, high bone uptake (16.1 ± 3.3% IA/g organ, 1h p.i.) and high bone-to-blood and bone-to-muscle radioactivity ratios, indicating that it is able to deliver radiation to bone in a very selective way. The radiocytotoxic effect elicited by (188)Re3 in the MDAMB231 cells was dependent on its concentration, and was higher than that induced by identical concentrations of [(188)ReO4](-). Additionally, (188)Re3 elicited morphological changes in the cells and induced DNA damage by the increased number of MN observed. Altogether, our results demonstrate that (188)Re3 could be considered an attractive candidate for further preclinical evaluation for systemic radionuclide therapy of bone metastases considering its ability to deliver radiation to bone in a very selective way and to induce radiation damage. Copyright © 2015 Elsevier Inc. All rights reserved.

Synthesis and evaluation of novel 18 F-labeled quinazoline derivatives with low lipophilicity for tumor PET imaging.

PubMed

Chong, Yan; Chang, Jin; Zhao, Wenwen; He, Yong; Li, Yuqiao; Zhang, Huabei; Qi, Chuanmin

2018-02-01

Four novel 18 F-labeled quinazoline derivatives with low lipophilicity, [ 18 F]4-(2-fluoroethoxy)-6,7-dimethoxyquinazoline ([ 18 F]I), [ 18 F]4-(3-((4-(2-fluoroethoxy)-7-methoxyquinazolin-6-yl)oxy)propyl)morpholine ([ 18 F]II), [ 18 F]4-(2-fluoroethoxy)-7-methoxy-6-(2-methoxyethoxy)quinazoline ([ 18 F]III), and [ 18 F]4-(2-fluoroethoxy)-6,7-bis(2-methoxyethoxy)quinazoline ([ 18 F]IV), were synthesized via a 2-step radiosynthesis procedure with an overall radiochemical yield of 10% to 38% (without decay correction) and radiochemical purities of >98%. The lipophilicity and stability of labeled compounds were tested in vitro. The log P values of the 4 radiotracers ranged from 0.52 to 1.07. We then performed ELISA to measure their affinities to EGFR-TK; ELISA assay results indicated that each inhibitor was specifically bounded to EGFR-TK in a dose-dependent manner. The EGFR-TK autophosphorylation IC 50 values of [ 18 F]I, [ 18 F]II, [ 18 F]III, and [ 18 F]IV were 7.732, 0.4698, 0.1174, and 0.1176 μM, respectively. All labeled compounds were evaluated via cellular uptake and blocking studies in HepG2 cell lines in vitro. Cellular uptake and blocking experiment results indicated that [ 18 F]I and [ 18 F]III had excellent cellular uptake at 120-minute postinjection in HepG2 carcinoma cells (51.80 ± 3.42%ID/mg protein and 27.31 ± 1.94%ID/mg protein, respectively). Additionally, biodistribution experiments in S180 tumor-bearing mice in vivo indicated that [ 18 F]I had a very fast clearance in blood and a relatively high uptake ratio of tumor to blood (4.76) and tumor to muscle (1.82) at 60-minute postinjection. [ 18 F]III had a quick clearance in plasma, and its highest uptake ratio of tumor to muscle was 2.55 at 15-minute postinjection. These experimental results and experiences were valuable for the further exploration of novel radiotracers of quinazoline derivatives. Copyright © 2017 John Wiley & Sons, Ltd.

Glenn T. Seaborg and heavy ion nuclear science

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

Loveland, W.

1992-04-01

Radiochemistry has played a limited but important role in the study of nucleus-nucleus collisions. Many of the important radiochemical studies have taken place in Seaborg's laboratory or in the laboratories of others who have spent time in Berkeley working with Glenn T. Seaborg. I will discuss studies of low energy deep inelastic reactions with special emphasis on charge equilibration, studies of the properties of heavy residues in intermediate energy nuclear collisions and studies of target fragmentation in relativistic and ultrarelativistic reactions. The emphasis will be on the unique information afforded by radiochemistry and the physical insight derived from radiochemical studies.more » Future roles of radiochemistry in heavy ion nuclear science also will be discussed.« less

Glenn T. Seaborg and heavy ion nuclear science

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

Loveland, W.

1992-04-01

Radiochemistry has played a limited but important role in the study of nucleus-nucleus collisions. Many of the important radiochemical studies have taken place in Seaborg`s laboratory or in the laboratories of others who have spent time in Berkeley working with Glenn T. Seaborg. I will discuss studies of low energy deep inelastic reactions with special emphasis on charge equilibration, studies of the properties of heavy residues in intermediate energy nuclear collisions and studies of target fragmentation in relativistic and ultrarelativistic reactions. The emphasis will be on the unique information afforded by radiochemistry and the physical insight derived from radiochemical studies.more » Future roles of radiochemistry in heavy ion nuclear science also will be discussed.« less

Feasibility of Isotope Harvesting at a Projectile Fragmentation Facility: 67Cu

PubMed Central

Mastren, Tara; Pen, Aranh; Peaslee, Graham F.; Wozniak, Nick; Loveless, Shaun; Essenmacher, Scott; Sobotka, Lee G.; Morrissey, David J.; Lapi, Suzanne E.

2014-01-01

The work presented here describes a proof-of-principle experiment for the chemical extraction of 67Cu from an aqueous beam stop at the National Superconducting Cyclotron Laboratory (NSCL). A 76 MeV/A 67Cu beam was stopped in water, successfully isolated from the aqueous solution through a series of chemical separations involving a chelating disk and anion exchange chromatography, then bound to NOTA-conjugated Herceptin antibodies, and the bound activity was validated using instant thin-layer chromatography (ITLC). The chemical extraction efficiency was found to be 88 ± 3% and the radiochemical yield was ≥95%. These results show that extraction of radioisotopes from an aqueous projectile-fragment beam dump is a feasible method for obtaining radiochemically pure isotopes. PMID:25330839

A mild, rapid synthesis of freebase [ 11C]nicotine from [ 11C]methyl triflate

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

Xu, Youwen; Kim, Sung Won; Kim, Dohyun

Here a rapid, mild radiosynthesis of freebase [ 11C]nicotine was developed by the methylation of freebase nornicotine with [ 11C]methyl triflate in acetone (5 min, 45 ºC). A basic (pH 10.5-11.0) HPLC system reproducibly yielded freebase [ 11C]nicotine as a well-defined single peak. The freebase [ 11C]nicotine was concentrated by solid phase extraction and formulated in 50 μL ethanol (370 MBq/50 μL) without evaporative loss suitable for a cigarette spiking study. A radiochemical yield of 60.4 ± 4.7 % (n = 3), radiochemical purity ≥ 99.9 % and specific activity of 648 GBq/μmol at EOB for 5 min beams weremore » achieved.« less

Evaluation of background concentrations of selected chemical and radiochemical constituents in water from the eastern Snake River Plain aquifer at and near the Idaho National Laboratory, Idaho

USGS Publications Warehouse

Bartholomay, Roy C.; L. Flint Hall,

2016-05-05

The upper limit of background concentrations for radiochemical constituents for eastern regional water was 5.43 ±0.574 pCi/L for tritium, 0.0002048 ±0.0000054 pCi/L for chlorine-36, 0.000000865 ±0.000000015 pCi/L for iodine-129, <0.0000054 pCi/L for technetium-99, 0 pCi/L for strontium-90, plutonium-238, plutonium-239, -240 (undivided), and americium-241, 1.32 ±0.77 pCi/L for uranium-234, 0.016 ±0.012 pCi/L for uranium-235, and 0.477 ±0.044 pCi/L for uranium-238.

Analysis of low levels of rare earths by radiochemical neutron activation analysis

USGS Publications Warehouse

Wandless, G.A.; Morgan, J.W.

1985-01-01

A procedure for the radiochemical neutron-activation analysis for the rare earth elements (REE) involves the separation of the REE as a group by rapid ion-exchange methods and determination of yields by reactivation or by energy dispersive X-ray fluorescence (EDXRF) spectrometry. The U. S. Geological Survey (USGS) standard rocks, BCR-1 and AGV-1, were analyzed to determine the precision and accuracy of the method. We found that the precision was ??5-10% on the basis of replicate analysis and that, in general the accuracy was within ??5% of accepted values for most REE. Data for USGS standard rocks BIR-1 (Icelandic basalt) and DNC-1 (North Carolina diabase) are also presented. ?? 1985 Akade??miai Kiado??.

Comparison of different methods for radiochemical purity testing of [99mTc-EDDA-HYNIC-D-Phe1,Tyr3]-octreotide.

PubMed

von Guggenberg, Elisabeth; Penz, Barbara; Kemmler, Georg; Virgolini, Irene; Decristoforo, Clemens

2006-02-01

[99mTc-EDDA-HYNIC-D-Phe1,Tyr3]-octreotide (99mTc-EDDA-HYNIC-TOC) is an alternative radioligand for somatostatin receptor (SSTR) scintigraphy of neuroendocrine tumours. In order to allow a rapid and accurate determination of the quality in the clinical routine the aim of this study was to evaluate different methods of radiochemical purity (RCP) testing. Three different methods of RCP testing were compared: high-performance liquid chromatography (HPLC), thin layer chromatography (TLC) and minicolumn (Sep-Pak purification = SPE). HPLC was shown to be the most effective method for the quality control. The use of TLC and SPE is only recommended after sufficient practical labelling experience.

A mild, rapid synthesis of freebase [ 11C]nicotine from [ 11C]methyl triflate

DOE PAGES

Xu, Youwen; Kim, Sung Won; Kim, Dohyun; ...

2016-08-29

Here a rapid, mild radiosynthesis of freebase [ 11C]nicotine was developed by the methylation of freebase nornicotine with [ 11C]methyl triflate in acetone (5 min, 45 ºC). A basic (pH 10.5-11.0) HPLC system reproducibly yielded freebase [ 11C]nicotine as a well-defined single peak. The freebase [ 11C]nicotine was concentrated by solid phase extraction and formulated in 50 μL ethanol (370 MBq/50 μL) without evaporative loss suitable for a cigarette spiking study. A radiochemical yield of 60.4 ± 4.7 % (n = 3), radiochemical purity ≥ 99.9 % and specific activity of 648 GBq/μmol at EOB for 5 min beams weremore » achieved.« less

Analysis of 161Tb by radiochemical separation and liquid scintillation counting

DOE PAGES

Jiang, J.; Davies, A.; Arrigo, L.; ...

2015-12-05

The determination of 161Tb activity is problematic due to its very low fission yield, short half-life, and the complication of its gamma spectrum. At AWE, radiochemically purified 161Tb solution was measured on a PerkinElmer 1220 Quantulus TM Liquid Scintillation Spectrometer. Since there was no 161Tb certified standard solution available commercially, the counting efficiency was determined by the CIEMAT/NIST Efficiency Tracing method. The method was validated during a recent inter-laboratory comparison exercise involving the analysis of a uranium sample irradiated with thermal neutrons. Lastly, the measured 161Tb result was in excellent agreement with the result using gamma spectrometry and the resultmore » obtained by Pacific Northwest National Laboratory.« less

The radiation chemistry of ionic liquids: A review

DOE PAGES

Mincher, Bruce J.; Wishart, James F.

2014-07-03

Ionic liquids have received increasing attention as media for radiochemical separations. Recent literature includes examinations of the efficiencies and mechanisms of the solvent extraction of lanthanides, actinides and fission products into ionic liquid solutions. For radiochemical applications, including as replacement solvents for nuclear fuel reprocessing, a thorough understanding of the radiation chemistry of ionic liquids will be required. Such an understanding can be achieved based on a combination of steady-state radiolysis experiments coupled with post-irradiation product identification and pulse-radiolysis experiments to acquire kinetic information. These techniques allow for the elucidation of radiolytic mechanisms. This contribution reviews the current ionic liquidmore » radiation chemistry literature as it affects separations, with these considerations in mind.« less

Natural and man-made radioactivity in soils and plants around the research reactor of Inshass.

PubMed

Higgy, R H; Pimpl, M

1998-12-01

The specific radioactivities of the U-series, 232Th, 137Cs and 40K were measured in soil samples around the Inshass reactor in Cairo, using a gamma-ray spectrometer with a HpGe detector. The alpha activity of 238U, 234U and 235U was measured in the same soil samples by surface barrier detectors after radiochemical separation and the obtained results were compared with the specific activities determined by gamma-measurements. The alpha-activity of 238Pu, 239+240Pu, 241Am, 242Cm and 244Cm was measured after radiochemical separation by surface barrier detectors for both soil and plant samples. Then beta-activity of 241Pu was measured using liquid scintillation spectrometry.

Rapid Radiochemical Methods for Selected Radionuclides

EPA Pesticide Factsheets

The rapid methods documents are supplement guidance in a planned series designed to present radioanalytical laboratory personnel, Incident Commanders (and their designees), and other field response personnel.

HYBRID FAST HANKEL TRANSFORM ALGORITHM FOR ELECTROMAGNETIC MODELING

EPA Science Inventory

A hybrid fast Hankel transform algorithm has been developed that uses several complementary features of two existing algorithms: Anderson's digital filtering or fast Hankel transform (FHT) algorithm and Chave's quadrature and continued fraction algorithm. A hybrid FHT subprogram ...

ERLN Water Focus Area

EPA Pesticide Factsheets

The Water Laboratory Alliance (WLA), within Environmental Response Laboratory Network, maintains analytical capability and capacity in the event of intentional and unintentional water contamination with chemical, biological and radiochemical contaminants.

SAM Methods Query

EPA Pesticide Factsheets

Laboratories measuring target chemical, radiochemical, pathogens, and biotoxin analytes in environmental samples can use this online query tool to identify analytical methods included in EPA's Selected Analytical Methods for Environmental Remediation

Radiochemical ageing of EPDM elastomers. 3. Mechanism of radiooxidation

NASA Astrophysics Data System (ADS)

Rivaton, A.; Cambon, S.; Gardette, J.-L.

2005-01-01

The preceding paper of this series was devoted to the identification and quantification of the main chemical changes resulting from the radiochemical ageing of EPDM (77.9% ethylene, 21.4% propylene, 0.7% diene) and EPR (76.6% ethylene, 23.4% propylene) films irradiated under oxygen atmosphere using 60Co gamma rays. The double bond of the diene was observed to be consumed with a high radiochemical yield. The oxidation and reticulation rates were observed to be higher in the case of EPDM than in EPR. Accumulation of the major oxidation products in both polymers was shown to occur in the order of decreasing concentrations: hydroperoxides, ketones, carboxylic acids and alcohols, peroxides. On the basis of the analysis of the oxidation products formed in EPDM and EPR, and taking into account their relative concentrations, the mechanisms accounting for the EPDM γ-degradation under oxygen atmosphere are proposed in the present paper. Two main processes are involved in the EPDM radiooxidation. The random γ-radiolysis of the polymer provides a constant source of macroalkyl radicals mainly formed on ethylene units. The secondary radicals so formed are likely to initiate a selective oxidation of the polymer through free-radicals reactions involving the abstraction of labile hydrogen atoms. In particular, the hydroperoxides decomposition and the consumption of the ENB moieties, this latter being the most oxidisable site and the source of crosslinking, may result from hydrogen abstraction by radical species.

The synthesis of [14 C]4-acetylphenylalanine, effect on cell viability, and assessment of protein incorporation in male rat hepatocytes.

PubMed

Maxwell, Brad D; Ly, Van; Brock, Barry; Dodge, Robert; Tirmenstein, Mark; Calvano, Jacqueline

2017-06-30

PEGylation is a proven approach to prolonging the duration of action and enhancing biophysical solubility and stability of peptides. 4-Acetylphenylalanine is a novel amino acid with a ketone side chain that is uniquely reactive in proteins. The ketone functionality can react with an aminooxy functionalized polyethyleneglycol polymer to form a stable oxime adduct of the protein. One concern with using unnatural amino acids, such as 4-acetylphenylalanine, is the possibility of it being cleaved from the peptide and becoming incorporated into endogenous proteins. To determine whether this occurs, an in vitro experiment to assess the cell viability and amino acid incorporation into endogenous proteins using primary male rat hepatocytes in the presence of [ 14 C]4-acetylphenylalanine, 4 or [ 14 C(U)]L-phenylalanine was conducted. [ 14 C]4-acetylphenylalanine, 4 was prepared in 2 radiochemical steps from [1- 14 C]acetyl chloride in an overall 8% radiochemical yield and in 99.9% radiochemical purity. The results showed that there was no evidence of carbon-14 incorporation into hepatocyte endogenous proteins with [ 14 C]pAcF and there was no difference between it and L-phenylalanine in cell viability assessments at any of the concentrations studied between 0.1 and 1000 μM. Copyright © 2017 John Wiley & Sons, Ltd.

Radiostrontium accumulation in animal bones: development of a radiochemical method by ultra low-level liquid scintillation counting for its quantification.

PubMed

Iammarino, Marco; Dell'Oro, Daniela; Bortone, Nicola; Mangiacotti, Michele; Chiaravalle, Antonio Eugenio

2018-03-31

Strontium-90 (90Sr) is a fission product, resulting from the use of uranium and plutonium in nuclear reactors and weapons. Consequently, it may be found in the environment as a consequence of nuclear fallouts, nuclear weapon testing, and not correct waste management. When present in the environment, strontium-90 may be taken into animal body by drinking water, eating food, or breathing air. The primary health effects are bone tumors and tumors of the blood-cell forming organs, due to beta particles emitted by both 90Sr and yttrium-90 (90Y). Moreover, another health concern is represented by inhibition of calcification and bone deformities in animals. Actually, radiometric methods for the determination of 90Sr in animal bones are lacking. This article describers a radiochemical method for the determination of 90Sr in animal bones, by ultra low-level liquid scintillation counting. The method precision and trueness have been demonstrated through validation tests (CV% = 12.4%; mean recovery = 98.4%). Detection limit and decision threshold corresponding to 8 and 3 mBecquerel (Bq) kg-1, respectively, represent another strong point of this analytical procedure. This new radiochemical method permits the selective extraction of 90Sr, without interferences, and it is suitable for radiocontamination surveillance programs, and it is also an improvement with respect to food safety controls.

Synthesis, Bioconjugation and Stability Studies of [18 F] Ethenesulfonyl Fluoride.

PubMed

Zhang, Bo; Pascali, Giancarlo; Wyatt, Naomi; Matesic, Lidia; Klenner, Mitchell A; Sia, Tiffany R; Guastella, Adam J; Massi, Massimiliano; Robinson, Andrea J; Fraser, Benjamin H

2018-06-20

Fluorine-18 labelled prosthetic groups (PGs) are often necessary for radiolabelling sensitive biological molecules such as peptides and proteins. Several shortcomings, however, often diminish the final yield of radiotracer. In an attempt to provide higher yielding and operationally efficient tools for radiolabelling biological molecules, we describe herein the first radiochemical synthesis of [ 18 F] ethenesulfonylfluoride ([ 18 F] ESF) and its Michael conjugation with amino acids and proteins. The synthesis of [ 18 F] ESF was optimised using a microfluidic reactor under both carrier-added (c.a.) and no-carrier-added (n.c.a.) conditions, affording, in a straightforward procedure, 30-50% radiochemical yield (RCY) for c.a. [ 18 F] ESF and 60-70% RCY for n.c.a. [ 18 F] ESF. The conjugation reactions were performed at room temperature using 10 mg/mL precursor in aqueous/organic solvent mixtures for 15 min. The radiochemical stability of the final conjugates was evaluated in injectable formulation and rat serum, and resulted strongly substrate dependent and generally poor in rat serum. Therefore, in this work we have optimised a straightforward synthesis of [ 18 F] ESF and its Michael conjugation with model compounds, without requiring chromatographic purification. However, given the general low stability of the final products, further studies will be required for improving conjugate stability, before assessing the use of this PG for PET imaging. This article is protected by copyright. All rights reserved.

Fast-slow asymptotics for a Markov chain model of fast sodium current

NASA Astrophysics Data System (ADS)

Starý, Tomáš; Biktashev, Vadim N.

2017-09-01

We explore the feasibility of using fast-slow asymptotics to eliminate the computational stiffness of discrete-state, continuous-time deterministic Markov chain models of ionic channels underlying cardiac excitability. We focus on a Markov chain model of fast sodium current, and investigate its asymptotic behaviour with respect to small parameters identified in different ways.

SAM Chemical Methods Query

EPA Pesticide Factsheets

Laboratories measuring target chemical, radiochemical, pathogens, and biotoxin analytes in environmental samples can use this online query tool to identify analytical methods in EPA's Selected Analytical Methods for Environmental Remediation and Recovery

Quality Control Guidelines for SAM Radiochemical Methods

EPA Pesticide Factsheets

Learn more about quality control guidelines and recommendations for the analysis of samples using the radiochemistry methods listed in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).

Feasibility of Isotope Harvesting at a Projectile Fragmentation Facility: 67Cu

DOE PAGES

Mastren, Tara; Pen, Aranh; Peaslee, Graham F.; ...

2014-10-21

The work presented here describes a proof-of-principle experiment for the chemical extraction of 67Cu from an aqueous beam stop at the National Superconducting Cyclotron Laboratory (NSCL). A 76 MeV/A 67Cu beam was stopped in water, successfully isolated from the aqueous solution through a series of chemical separations involving a chelating disk and anion exchange chromatography, then bound to NOTA-conjugated Herceptin antibodies, and the bound activity was validated using instant thin-layer chromatography (ITLC). The chemical extraction efficiency was found to be 88 ± 3% and the radiochemical yield was ≥95%. These results show that extraction of radioisotopes from an aqueous projectile-fragmentmore » beam dump is a feasible method for obtaining radiochemically pure isotopes.« less

Applying a low energy HPGe detector gamma ray spectrometric technique for the evaluation of Pu/Am ratio in biological samples.

PubMed

Singh, I S; Mishra, Lokpati; Yadav, J R; Nadar, M Y; Rao, D D; Pradeepkumar, K S

2015-10-01

The estimation of Pu/(241)Am ratio in the biological samples is an important input for the assessment of internal dose received by the workers. The radiochemical separation of Pu isotopes and (241)Am in a sample followed by alpha spectrometry is a widely used technique for the determination of Pu/(241)Am ratio. However, this method is time consuming and many times quick estimation is required. In this work, Pu/(241)Am ratio in the biological sample was estimated with HPGe detector based measurements using gamma/X-rays emitted by these radionuclides. These results were compared with those obtained from alpha spectroscopy of sample after radiochemical analysis and found to be in good agreement. Copyright © 2015 Elsevier Ltd. All rights reserved.

Radiochemical Processing Laboratory (RPL) at PNNL

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

Peurrung, Tony; Clark, Sue; Bryan, Sam

2017-03-23

Nuclear research is one of the core components of PNNL's mission. The centerpiece of PNNL's nuclear research is the Radiochemical Processing Laboratory (RPL), a Category 2 nuclear facility with state-of-the-art instrumentation, scientific expertise, and specialized capabilities that enable research with significant quantities of fissionable materials and other radionuclides—from tritium to plutonium. High impact radiological research has been conducted in the RPL since the 1950's, when nuclear weapons and energy production at Hanford were at the forefront of national defense. Since then, significant investments have been made in the RPL to maintain it as a premier nuclear science research facility supportingmore » multiple programs. Most recently, PNNL is developing a world-class analytical electron microscopy facility dedicated to the characterization of radiological materials.« less

Synthesis of [¹¹C]PBR170, a novel imidazopyridine, for imaging the translocator protein with PET.

PubMed

Bourdier, Thomas; Henderson, David; Fookes, Christopher J R; Lam, Peter; Mattner, Filomena; Fulham, Michael; Katsifis, Andrew

2014-08-01

The translocator protein (TSPO) ligand 2-(6,8-dichloro-2-(4-ethoxyphenyl)imidazo[1,2-a]pyridin-3-yl)-N-(2-fluoropyridin-3-yl)-N-methylacetamide (PBR170), is a novel imidazopyridineacetamide with high affinity (2.6 nm) and selectivity for the TSPO. The synthesis of [(11)C]PBR170 was accomplished by N-methylation of the corresponding desmethyl precursor with [(11)C]methyl iodide in the presence of sodium hydroxide in dimethylformamide. [(11)C]PBR170 was produced in 30-45% radiochemical yield (decay-corrected, based on [(11)C]methyl iodide) with a radiochemical purity >98% and a specific activity of 90-190 GBq/μmol after 35 min of synthesis time. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

A LabVIEW®-based software for the control of the AUTORAD platform: a fully automated multisequential flow injection analysis Lab-on-Valve (MSFIA-LOV) system for radiochemical analysis.

PubMed

Barbesi, Donato; Vicente Vilas, Víctor; Millet, Sylvain; Sandow, Miguel; Colle, Jean-Yves; Aldave de Las Heras, Laura

2017-01-01

A LabVIEW ® -based software for the control of the fully automated multi-sequential flow injection analysis Lab-on-Valve (MSFIA-LOV) platform AutoRAD performing radiochemical analysis is described. The analytical platform interfaces an Arduino ® -based device triggering multiple detectors providing a flexible and fit for purpose choice of detection systems. The different analytical devices are interfaced to the PC running LabVIEW ® VI software using USB and RS232 interfaces, both for sending commands and receiving confirmation or error responses. The AUTORAD platform has been successfully applied for the chemical separation and determination of Sr, an important fission product pertinent to nuclear waste.

Radiochemical Reactions Between Tritium Molecule and Carbon Dioxide

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

Shu, W.M.; O'Hira, S.; Suzuki, T.

To have better understanding of radiochemical reactions among oxygen baking products in a fusion reactor, reactions in equimolar tritium molecule (T{sub 2}) and carbon dioxide (CO{sub 2}) were examined by laser Raman spectroscopy and mass spectrometry. After mixing them at room temperature, T{sub 2} and CO{sub 2} decreased rapidly in the first 30 minutes and then the reactions between them became much slower. As the predominant products of the reactions, carbon monoxide (CO) and tritiated water (T{sub 2}O) were found in gaseous phase and condensed phase, respectively. However, there likely existed also some solid products that were thermally decomposed intomore » CO, CO{sub 2}, T{sub 2}, T{sub 2}O, etc. during baking up to 523 K.« less

A novel five-lipoxygenase activity protein inhibitor labeled with carbon-14 and deuterium.

PubMed

Latli, Bachir; Hrapchak, Matt; Gao, Joe J; Busacca, Carl A; Senanayake, Chris H

2015-07-01

2-[4-(3-{(1R)-1-[4-(2-Aminopyrimidin-5-yl)phenyl]-1-cyclopropylethyl}-1,2,4-oxadiazol-5-yl)-1H-pyrazol-1-yl]-N,N-dimethylacetamide (1), is a novel and selective five-lipoxygenase activity protein (FLAP) inhibitor with excellent pharmacokinetics properties. The availability of a key chiral intermediate allowed the synthesis of [(14) C]-(1) in six radiochemical steps and in 47% overall radiochemical yield with a specific activity of 51 mCi/mmol using carbon-14 zinc cyanide. 2-Chloro-N,N-dimethyl-(2)H6-acetamide was prepared and condensed with a penultimate intermediate to give [(2)H6]-(1) in very high yield and in more than 99% isotopic enrichment. Copyright © 2015 John Wiley & Sons, Ltd.

Automated synthesis of 4-[(18)F]fluoroanisole, [(18)F]DAA1106 and 4-[(18)F]FPhe using Cu-mediated radiofluorination under "minimalist" conditions.

PubMed

Zischler, Johannes; Krapf, Philipp; Richarz, Raphael; Zlatopolskiy, Boris D; Neumaier, Bernd

2016-09-01

The application of the "minimalist" approach to Cu-mediated radiofluorination allows the efficient preparation of (18)F-labeled arenes regardless of their electronic properties. The implementation of this methodology on a commercially available synthesis module (hotbox(three), Scintomics, Germany) enabled the automated production of 4-[(18)F]fluoroanisole as well as the clinically relevant PET-tracers, 4-[(18)F]FPhe and [(18)F]DAA1106, in radiochemical yields of 41-61% and radiochemical purities of >95% within 30-60min. These results demonstrated the high efficacy and versatility of the developed method that will open up opportunities for a broad application of Cu-mediated radiofluorination in PET-chemistry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radiochemical monitoring of water after the Cannikin event, Amchitka Island, Alaska, August 1974 and chemical monitoring from July 1972 to June 1974

USGS Publications Warehouse

Ballance, Wilbur C.; Thordarson, William

1976-01-01

Radiochemical data from the Arnchitka Island study area were obtained from water samples collected by the U.S. Geological Survey during August 1974. Tritium determinations were made on 18 samples, and gross alpha and gross beta/ gamma determinations were made on 12 samples. No appreciable differences were found between the data obtained during August 1974 and the data obtained before the Cannikin event. Chemical analyses were made on 4 samples collected in 1971, on 15 samples in 1972, on 11 samples in 1973, and 7 samples in 1974. Comparison of these analyses to analyses of samples collected before the Cannikin event indicates no changes outside of the seasonal range normally found at the sampling locations.

Synthesis, characterization and biological evaluation of a novel "3 + 1" mixed ligand 99mTc complex having an aliphatic thiol as coligand.

PubMed

Rey, A; Papadopoulos, M; Leon, E; Mallo, L; Pirmettis, Y; Manta, E; Raptopoulou, C; Chiotellis, E; Leon, A

2001-03-01

A novel "3 + 1" mixed ligand 99mTc complex with N,N-bis(2-mercaptoethyl)-N'N'-diethyl-ethilenediamine as ligand and 1-octanethiol as coligand was prepared and evaluated as potential brain radiopharmaceutical. Preparation at tracer level was accomplished by substitution, using 99mTc-glucoheptonate as precursor and a coligand/ligand ratio of 5. Under these conditions the labeling yield was over 80% and a major product with radiochemical purity >80% was isolated by HPLC methods and used for biological evaluation. Chemical characterization at carrier level was developed using the corresponding rhenium and 99gTc complexes. Results were consistent with the expected "3 + 1" structure and X-ray diffraction study demonstrated that the complex adopted a distorted trigonal bipyramidal geometry. All sulphur atoms underwent ionization leading to the formation of a neutral compound. Biodistribution in mice demonstrated early brain uptake, fast blood clearance and excretion through hepatobiliary system. Although brain/blood ratio increased significantly with time, this novel 99mTc complex did not exhibit ideal properties as brain perfusion radiopharmaceutical since brain uptake was too low.

Absorbed dose assessment of 177Lu-zoledronate and 177Lu-EDTMP for human based on biodistribution data in rats

PubMed Central

Yousefnia, Hassan; Zolghadri, Samaneh; Jalilian, Amir Reza

2015-01-01

Over the past few decades, several bone-seeking radiopharmaceuticals including various bisphosphonate ligands and β-emitting radionuclides have been developed for bone pain palliation. Recently, 177Lu was successfully labeled with zoledronic acid (177Lu-ZLD) as a new generation potential bisphosphonate and demonstrated significant accumulation in bone tissue. In this work, the absorbed dose to each organ of human for 177Lu-ZLD and 177Lu-ethylenediaminetetramethylene phosphonic acid (177Lu-EDTMP;as the only clinically bone pain palliation agent) was investigated based on biodistribution data in rats by medical internal radiation dosimetry (MIRD) method. 177Lu-ZLD and 177Lu-EDTMP were prepared in high radiochemical purity (>99%, instant thin layer chromatography (ITLC)) at the optimized condition. The biodistribution of the complexes demonstrated fast blood clearance and major accumulation in the bone tissue. The highest absorbed dose for both 177Lu-ZLD and 177Lu-EDTMP is observed in trabecular bone surface with 12.173 and 10.019 mSv/MBq, respectively. The results showed that 177Lu-ZLD has better characteristics compared to 177Lu-EDTMP and can be a good candidate for bone pain palliation. PMID:26170557

Synthesis, characterization and in vivo evaluation of [(62)Zn]-benzo-δ-sultam complex as a possible pet imaging agent.

PubMed

Ghandi, Mehdi; Feizi, Shahzad; Ziaie, Farhood; Fazaeli, Yousef; Notash, Behrooz

2014-11-01

The development of a new tracer based on the cyclic sulfonamides (sultams) was investigated. 3-(Methoxy-phenyl-methyl)-1,6-dimethyl-1H benzo[c][1,2] thiazine 2,2-dioxide (benzo-δ-sultam) was synthesized and characterized by elemental analysis, FT-IR spectroscopy and single crystal X-ray structure determination. The prepared cyclic sulfonamide was labeled with non-commercial (62)Zn radioisotope for fast in vivo targeting and Coincidence imaging purposes (radiochemical purity 97 % ITLC, 96 % HPLC, specific activity 20-23 GBq/mmol). In vivo biodistribution of the final complex was investigated in Sprague Dawley(®) rats bearing fibro sarcoma tumor after 2, 4 and 8 h post injection and compared with free Zn(+2) cation. Using instant paper chromatography method, the physicochemical properties of labeled compounds were found sufficiently stable in organic phases, e.g. a human serum, to be reliably used in bioapplications. The complex exhibited a rapid as well as high tumor uptake (tumor to blood ratio 4.38 and tumor to muscle ratio 9.63) resulting in an efficient tumor targeting agent.

Low level radioactivity measurements with phoswich detectors using coincident techniques and digital pulse processing analysis.

PubMed

de la Fuente, R; de Celis, B; del Canto, V; Lumbreras, J M; de Celis Alonso, B; Martín-Martín, A; Gutierrez-Villanueva, J L

2008-10-01

A new system has been developed for the detection of low radioactivity levels of fission products and actinides using coincidence techniques. The device combines a phoswich detector for alpha/beta/gamma-ray recognition with a fast digital card for electronic pulse analysis. The phoswich can be used in a coincident mode by identifying the composed signal produced by the simultaneous detection of alpha/beta particles and X-rays/gamma particles. The technique of coincidences with phoswich detectors was proposed recently to verify the Nuclear Test Ban Treaty (NTBT) which established the necessity of monitoring low levels of gaseous fission products produced by underground nuclear explosions. With the device proposed here it is possible to identify the coincidence events and determine the energy and type of coincident particles. The sensitivity of the system has been improved by employing liquid scintillators and a high resolution low energy germanium detector. In this case it is possible to identify simultaneously by alpha/gamma coincidence transuranic nuclides present in environmental samples without necessity of performing radiochemical separation. The minimum detectable activity was estimated to be 0.01 Bq kg(-1) for 0.1 kg of soil and 1000 min counting.

18F-Fluorosulfate for PET Imaging of the Sodium-Iodide Symporter: Synthesis and Biologic Evaluation In Vitro and In Vivo.

PubMed

Khoshnevisan, Alex; Chuamsaamarkkee, Krisanat; Boudjemeline, Mehdi; Jackson, Alex; Smith, Gareth E; Gee, Antony D; Fruhwirth, Gilbert O; Blower, Philip J

2017-01-01

Anion transport by the human sodium-iodide symporter (hNIS) is an established target for molecular imaging and radionuclide therapy. Current radiotracers for PET of hNIS expression are limited to 124 I - and 18 F-BF 4 - We sought new 18 F-labeled hNIS substrates offering higher specific activity, higher affinity, and simpler radiochemical synthesis than 18 F-BF 4 - METHODS: The ability of a range of anions, some containing fluorine, to block 99m TcO 4 - uptake in hNIS-expressing cells was measured. SO 3 F - emerged as a promising candidate. 18 F-SO 3 F - was synthesized by reaction of 18 F - with SO 3 -pyridine complex in MeCN and purified using alumina and quaternary methyl ammonium solid-phase extraction cartridges. Chemical and radiochemical purity and serum stability were determined by radiochromatography. Radiotracer uptake and efflux in hNIS-transduced HCT116-C19 cells and the hNIS-negative parent cell line were evaluated in vitro in the presence and absence of a known competitive inhibitor (NaClO 4 ). PET/CT imaging and ex vivo biodistribution measurement were conducted on BALB/c mice, with and without NaClO 4 inhibition. Fluorosulfate was identified as a potent inhibitor of 99m TcO 4 - uptake via hNIS in vitro (half-maximal inhibitory concentration, 0.55-0.56 μM (in comparison with 0.29-4.5 μM for BF 4 - , 0.07 μM for TcO 4 - , and 2.7-4.7 μM for I - ). Radiolabeling to produce 18 F-SO 3 F - was simple and afforded high radiochemical purity suitable for biologic evaluation (radiochemical purity > 95%, decay-corrected radiochemical yield = 31.6%, specific activity ≥ 48.5 GBq/μmol). Specific, blockable hNIS-mediated uptake in HCT116-C19 cells was observed in vitro, and PET/CT imaging of normal mice showed uptake in thyroid, salivary glands (percentage injected dose/g at 30 min, 563 ± 140 and 32 ± 9, respectively), and stomach (percentage injected dose/g at 90 min, 68 ± 21). Fluorosulfate is a high-affinity hNIS substrate. 18 F-SO 3 F - is easily synthesized in high yield and very high specific activity and is a promising candidate for preclinical and clinical PET imaging of hNIS expression and thyroid-related disease; it is the first example of in vivo PET imaging with a tracer containing an S- 18 F bond. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

EBCO Technologies TR Cyclotrons, Dynamics, Equipment, and Applications

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

Johnson, R.R.; Univ British Columbia; Erdman, K. L.

2003-08-26

The Ebco Technologies TR cyclotrons have a common parent in the 500 MeV negative ion cyclotron at TRIUMF in Vancouver. As such, the TR cyclotrons have features that can be adapted for specific application. The cyclotron design is modularized into ion source and injection system, central region and then extraction. The cyclotron ion source is configured for cyclotron beam currents ranging from 50 microAmps to 2 milliAmps. The injection line can be operated in either continuous (CW) or in pulsed mode. The center region of the cyclotron is configured to match the ion source configuration. The extracted beams are directedmore » either to a local target station or to beam lines and thence to target stations. There has been development both in solid, liquid and gas targets. There has been development in radioisotope handling techniques, target material recovery and radiochemical synthesis.« less

Preparation of [(68)Ga]PSMA-11 for PET-CT imaging using a manual synthesis module and organic matrix based (68)Ge/(68)Ga generator.

PubMed

Nanabala, Raviteja; Anees, Muhammed K; Sasikumar, Arun; Joy, Ajith; Pillai, M R A

2016-08-01

[(68)Ga]PSMA-11 is a relatively recently introduced radiopharmaceutical for PET-CT imaging of prostate cancer patients. The availability of (68)Ge/(68)Ga generator and PSMA-11 ligand from commercial sources is facilitating the production of the radiopharmaceutical in-house. This paper describes our experience on the preparation of ~200 batches of [(68)Ga]PSMA-11 for conducting PET-CT imaging in patients suspected/suffering from prostate cancer. The radiosynthesis of [(68)Ga]PSMA-11 was done in a hospital based nuclear medicine department using (68)Ge/(68)Ga generator and a manual synthesis module, both supplied by Isotope Technologies Garching (ITG), Germany. The production involved the reaction of 5μg (5.3nmol) of PSMA-11 ligand in 1 ml of 0.25M sodium acetate buffer with 4ml of (68)GaCl3 in 0.05M HCl for 5min at 105°C; followed by purification in a C18 cartridge and collection through a 0.22μm pore size filter. The radiochemical yields obtained were consistently high, 93.19%±3.76%, and there was hardly any batch failure. The radiochemical purity of the product was >99% and the product was stable for over 2h; however it was used in patients immediately after preparation. About 200 batches of [(68)Ga]PSMA-11 were prepared during the period and more than 300 patients received the tracer during the 14months of study. No adverse reaction was observed in any of the patients and the image qualities were consistent with literature reports. [(68)Ga]PSMA-11 with high radiochemical and radionuclidic purity is conveniently prepared by using a (68)Ge/(68)Ga generator and manual synthesis module. The radiochemical yields are very high; and activity sufficient for 3-4 patients can be prepared in a single batch; multiple batches can be done on the same day and when needed after a gap of 1.5-2h. Copyright © 2016 Elsevier Inc. All rights reserved.

A combined simple bubbling method with high performance liquid chromatography purification strategy, higher radiochemical yield and purity and faster preparation of carbon-11-raclopride.

PubMed

Huang, Huacheng; Ning, Yanli; Zhang, Bucheng; Lou, Cen

2015-01-01

Carbon-11-raclopride (¹¹C-R) is a positron-emitting radiotracer successfully used for the study of cognitive control and widely applied in PET imaging. A simple automated preparation of ¹¹C-R by using the reaction of carbon-(11)-methyl triflate (¹¹C-MeOTF) or ¹¹C-methyl iodide (¹¹C-MeI) with demethylraclopride is described. Specifically we used a simple setup applied an additional "U" reaction vessel for ¹¹C-MeOTf compared with ¹¹C-MeI and assessed the influence of several solvents and of the amount of the percussor for ¹¹C-methylation of demethylraclopride by the bubbling method. The reversal of retention order between product and its precursor has been achieved for ¹¹C-R, enabling collection of the purified ¹¹C-R by using the HPLC column after shorter retention time. By the improved radiosynthesis and purification strategy, ¹¹C-R could be prepared with higher radiochemical yield than that of the previous studies. The yield for ¹¹C-MeOTf was 76% and for ¹¹C-CH3I >26% and with better radiochemical purity (>99% based on both ¹¹C-MeOTf and ¹¹C-MeI) as compared to the previously obtained purity of ¹¹C-R using HPLC method with acetonitrile as a part of mobile phase. Furthermore, by using ethanol as the organic modifier, residual solvent analysis prior to human injection could be avoided and ¹¹C-R could be injected directly following simple dilution and sterile filtration. Improved radiosynthesis and HPLC purification in combination with ethanol containing eluent, extremely shortened the time for preparation of ¹¹C-R, gave a higher radiochemical yield and purity for ¹¹C-R and can be used for multiple and faster synthesis of ¹¹C-R and probably for other ¹¹C-labeled radiopharmaceuticals.

Studying Fast Reactions: Construction and Use of a Low-Cost Continuous-Flow Instrument

ERIC Educational Resources Information Center

Bisson, Patrick J.; Whitten, James E.

2006-01-01

The construction and use of a low-cost continuous-flow instrument for measuring the kinetics of fast reaction which include the use of an light emitting diode light source, a photodiode-on-a-chip detector, and a position sensor is demonstrated. The instrument is suitable for the physical chemistry laboratory and could be used to study the kinetics…

Analytical and Radiochemistry for Nuclear Forensics

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

Steiner, Robert Ernest; Dry, Donald E.; Kinman, William Scott

Information about nonproliferation nuclear forensics, activities in forensics at Los Alamos National Laboratory, radio analytical work at LANL, radiochemical characterization capabilities, bulk chemical and materials analysis capabilities, and future interests in forensics interactions.

Earthquake detection through computationally efficient similarity search

PubMed Central

Yoon, Clara E.; O’Reilly, Ossian; Bergen, Karianne J.; Beroza, Gregory C.

2015-01-01

Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection—identification of seismic events in continuous data—is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact “fingerprints” of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes. PMID:26665176

Left ventricle: fully automated segmentation based on spatiotemporal continuity and myocardium information in cine cardiac magnetic resonance imaging (LV-FAST).

PubMed

Wang, Lijia; Pei, Mengchao; Codella, Noel C F; Kochar, Minisha; Weinsaft, Jonathan W; Li, Jianqi; Prince, Martin R; Wang, Yi

2015-01-01

CMR quantification of LV chamber volumes typically and manually defines the basal-most LV, which adds processing time and user-dependence. This study developed an LV segmentation method that is fully automated based on the spatiotemporal continuity of the LV (LV-FAST). An iteratively decreasing threshold region growing approach was used first from the midventricle to the apex, until the LV area and shape discontinued, and then from midventricle to the base, until less than 50% of the myocardium circumference was observable. Region growth was constrained by LV spatiotemporal continuity to improve robustness of apical and basal segmentations. The LV-FAST method was compared with manual tracing on cardiac cine MRI data of 45 consecutive patients. Of the 45 patients, LV-FAST and manual selection identified the same apical slices at both ED and ES and the same basal slices at both ED and ES in 38, 38, 38, and 41 cases, respectively, and their measurements agreed within -1.6 ± 8.7 mL, -1.4 ± 7.8 mL, and 1.0 ± 5.8% for EDV, ESV, and EF, respectively. LV-FAST allowed LV volume-time course quantitatively measured within 3 seconds on a standard desktop computer, which is fast and accurate for processing the cine volumetric cardiac MRI data, and enables LV filling course quantification over the cardiac cycle.

Environmental Sampling & Analytical Methods (ESAM) Program - Home

EPA Pesticide Factsheets

ESAM is a comprehensive program to facilitate a coordinated response to a chemical, radiochemical, biotoxin or pathogen contamination incident focusing on sample collection, processing, and analysis to provide quality results to the field.

General Safety and Waste Management Related to SAM

EPA Pesticide Factsheets

The General Safety and Waste Management page offers section-specific safety and waste management details for chemicals, radiochemicals, pathogens, and biotoxins included in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).

Quantitative radiochemical method for determination of major sources of natural radioactivity in ores and minerals

USGS Publications Warehouse

Rosholt, J.N.

1954-01-01

When an ore sample contains radioactivity other than that attributable to the uranium series in equilibrium, a quantitative analysis of the other emitters must be made in order to determine the source of this activity. Thorium-232, radon-222, and lead-210 have been determined by isolation and subsequent activity analysis of some of their short-lived daughter products. The sulfides of bismuth and polonium are precipitated out of solutions of thorium or uranium ores, and the ??-particle activity of polonium-214, polonium-212, and polonium-210 is determined by scintillation-counting techniques. Polonium-214 activity is used to determine radon-222, polonium-212 activity for thorium-232, and polonium-210 for lead-210. The development of these methods of radiochemical analysis will facilitate the rapid determination of some of the major sources of natural radioactivity.

Are C1 chondrites chemically fractionated - A trace element study

NASA Technical Reports Server (NTRS)

Ebihara, M.; Wolf, R.; Anders, E.

1982-01-01

Six C1 chondrite samples and a C2 xenolith from the Plainview H5 chondrite were analyzed by radiochemical neutron activation for a large variety of elements, including rare earths. The sample processing is described, including the irradiation, chemical procedure, rare earths separation, counting techniques, radiochemical purity check, and chemical yields. The results of consistency checks on a number of elements are discussed. Abundances for siderophiles, volatiles, and rare earths are presented and discussed. Tests are presented for fractionation of rare earths and other refractories, compositional uniformity of C1's, and interelement correlations. There is no conclusive evidence for nebular fractionation affecting C1's. Three fractionation-prone rare earths have essentially the same relative abundances in C1's and all other chondrite classes, and hence are apparently not fractionated in C1's.

Mortality among workers with chronic radiation sickness

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

Shilnikova, N.S.; Koshurnikova, N.A.; Bolotnikova, M.G.

1996-07-01

This study is based on a registry containing medical and dosimetric data of the employees who began working at different plants of the Mayak nuclear complex between 1948 and 1958 who developed chronic radiation sickness. Mayak is the first nuclear weapons plutonium production enterprise built in Russia and includes nuclear reactors, a radiochemical plant for plutonium separation, and a plutonium production enterprise built in Russia and includes nuclear reactors, a radiochemical plant for plutonium separation, and a plutonium production plant.Workers whose employment began between 1948 and 1958 exhibited a 6-28% incidence of chronic radiation sickness at the different facilities. Theremore » were no cases of chronic radiation sickness among those who began working after 1958. Data on doses of external whole-body gamma-irradiation and mortality in workers with chronic radiation sickness are presented. 6 refs., 5 tabs.« less

Chasing the ghost particle: The long and winding road toward the detection of solar neutrinos

NASA Astrophysics Data System (ADS)

Leone, Matteo; Robotti, Nadia

2015-10-01

One of the great achievements of neutrino physics was the discovery of solar neutrinos in 1968 through the Homestake underground experiment. This experiment exploited a radiochemical method based on the chlorine-argon process of inverse beta decay suggested by Bruno Pontecorvo in 1946 during his work in the classified Canadian nuclear project. In this paper, we study the emergence of the method. We focus on the role played by the problematic status of the neutrino and its antiparticle in its field of application and the influence exerted by the contemporary models of energy production in the sun. We also provide evidence that a first germ of this radiochemical method, in the form of a chlorine-sulfur process, was suggested in a paper published by Richard Crane in late 1930s.

Complementarity in radiochemical and infrared spectroscopic characterization of electrode adsorption

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

Wieckowski, A.

1994-03-01

Radioactive labelling and infrared spectroscopy are frequently used as direct, in situ probes into the structure of the electrochemical solid/liquid interface. These techniques are compared, in a polemical fashion, in the context of a recent publication by Parry et al. (Langmuir 1993, 9, 1878) where the research potential of the former technique was not adequately depicted. It is shown that radiotracers can clearly differentiate between the surface and solution species, both neutrals and anions. In addition to the surface specificity, the radiotracers offer a quantitative determination of adsorbate surface concentrations, a feature not yet demonstrated with surface infrared spectroscopy inmore » electrochemistry. Therefore, these two techniques are complementary. Examples of the combined radiochemical and spectroscopic measurements of adsorption with equivalent (smooth) electrode surfaces are quoted. 11 refs., 2 figs.« less

Carbon-14 radiolabelling and tissue distribution evaluation of a potential anti-TB compound.

PubMed

Sonopo, Molahlehi S; Venter, Kobus; Winks, Susan; Marjanovic-Painter, Biljana; Morgans, Garreth L; Zeevaart, Jan R

2016-06-15

This paper describes a five-step synthesis of a carbon-14-labelled pyrazole compound (11). A total of 2.96 MBq of 11 was obtained with the specific activity of 2242.4 MBq/mmol. The radiochemical purity was >99%, and the overall radiochemical yield was 60% based on the [(14) C6 ] 4-bromoaniline starting material. Biodistribution results showed that the radiotracer (administrated orally) has a high accumulation in the small intestine, large intestine and liver of both non-infected and tuberculosis (TB)-infected mice. Therefore, this suggests that compound 11 undergoes hepatobiliary clearance. The compound under investigation has been found to be slowly released from the liver between 2 and 8 h. The study revealed that 11 has no affinity for TB cells. Copyright © 2016 John Wiley & Sons, Ltd.

Radiochemical analyses of surface water from U.S. Geological Survey hydrologic bench-mark stations

USGS Publications Warehouse

Janzer, V.J.; Saindon, L.G.

1972-01-01

The U.S. Geological Survey's program for collecting and analyzing surface-water samples for radiochemical constituents at hydrologic bench-mark stations is described. Analytical methods used during the study are described briefly and data obtained from 55 of the network stations in the United States during the period from 1967 to 1971 are given in tabular form.Concentration values are reported for dissolved uranium, radium, gross alpha and gross beta radioactivity. Values are also given for suspended gross alpha radioactivity in terms of natural uranium. Suspended gross beta radioactivity is expressed both as the equilibrium mixture of strontium-90/yttrium-90 and as cesium-137.Other physical parameters reported which describe the samples include the concentrations of dissolved and suspended solids, the water temperature and stream discharge at the time of the sample collection.

Inter-laboratory comparison measurements of radiochemical laboratories in Slovakia.

PubMed

Meresová, J; Belanová, A; Vrsková, M

2010-01-01

The first inter-laboratory comparison organized by the radiochemistry laboratory of Water Research Institute (WRI) in Bratislava was carried out in 1993 and since then is it realized on an annual basis and about 10 radiochemical laboratories from all over Slovakia are participating. The gross alpha and gross beta activities, and the activity concentrations of (222)Rn, tritium, and (226)Ra, and U(nat) concentration in synthetic water samples are compared. The distributed samples are covering the concentration range prevailing in potable and surface waters and are prepared by dilution of certified reference materials. Over the course of the years 1993-2008, we observed the improvement in the quality of results for most of the laboratories. However, the success rate of the gross alpha determination activity is not improving as much as the other parameters. Copyright 2009 Elsevier Ltd. All rights reserved.

Determination of radionuclides and radiochemical impurities produced by in-house cyclotron irradiation and subsequent radiosynthesis of PET tracers.

PubMed

Ishiwata, Kiichi; Hayashi, Kunpei; Sakai, Masanari; Kawauchi, Sugio; Hasegawa, Hideaki; Toyohara, Jun

2017-01-01

To elucidate the radionuclides and radiochemical impurities included in radiosynthesis processes of positron emission tomography (PET) tracers. Target materials and PET tracers were produced using a cyclotron/synthesis system from Sumitomo Heavy Industry. Positron and γ-ray emitting radionuclides were quantified by measuring radioactivity decay and using the high-purity Ge detector, respectively. Radiochemical species in gaseous and aqueous target materials were analyzed by gas and ion chromatography, respectively. Target materials had considerable levels of several positron emitters in addition to the positron of interest, and in the case of aqueous target materials extremely low levels of many γ-emitters. Five 11 C-, 15 O-, or 18 F-labeled tracers produced from gaseous materials via chemical reactions had no radionuclidic impurities, whereas 18 F-FDG, 18 F-NaF, and 13 N-NH 3 produced from aqueous materials had several γ-emitters as well as impure positron emitters. 15 O-Labeled CO 2 , O 2 , and CO had a radionuclidic impurity 13 N-N 2 (0.5-0.7 %). Target materials had several positron emitters other than the positron of interest, and extremely low level γ-emitters in the case of aqueous materials. PET tracers produced from gaseous materials except for 15 O-labeled gases had no impure radionuclides, whereas those derived from aqueous materials contained acceptable levels of impure positron emitters and extremely low levels of several γ-emitters.

Radiochemistry and the Study of Fission

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

Rundberg, Robert S.

These are slides from a lecture given at UC Berkeley. Radiochemistry has been used to study fission since its discovery. Radiochemical methods are used to determine cumulative mass yields. These measurements have led to the two-mode fission hypothesis to model the neutron energy dependence of fission product yields. Fission product yields can be used for the nuclear forensics of nuclear explosions. The mass yield curve depends on both the fuel and the neutron spectrum of a device. Recent studies have shown that the nuclear structure of the compound nucleus can affect the mass yield distribution. The following topics are covered:more » In the beginning: the discovery of fission; forensics using fission products: what can be learned from fission products, definitions of R-values and Q-values, fission bases, K-factors and fission chambers, limitations; the neutron energy dependence of the mass yield distribution (the two mode fission hypothesis); the influence of nuclear structure on the mass yield distribution. In summary: Radiochemistry has been used to study fission since its discovery. Radiochemical measurement of fission product yields have provided the highest precision data for developing fission models and for nuclear forensics. The two-mode fission hypothesis provides a description of the neutron energy dependence of the mass yield curve. However, data is still rather sparse and more work is needed near second and third chance fission. Radiochemical measurements have provided evidence for the importance of nuclear states in the compound nucleus in predicting the mass yield curve in the resonance region.« less

Radiolabeled cyclic arginine-glycine-aspartic (RGD)-conjugated iron oxide nanoparticles as single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) dual-modality agents for imaging of breast cancer

NASA Astrophysics Data System (ADS)

Deng, Shengming; Zhang, Wei; Zhang, Bin; Hong, Ruoyu; Chen, Qing; Dong, Jiajia; Chen, Yinyiin; Chen, Zhiqiang; Wu, Yiwei

2015-01-01

Ultrasmall superparamagnetic iron oxide nanoparticles (USPIOs) modified with a novel cyclic arginine-glycine-aspartate (RGD) peptide were made and radiolabeled as single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) dual-modality agents for imaging of breast cancer. The probe was tested both in vitro and in vivo to determine its receptor targeting efficacy and feasibility for SPECT and MRI. The radiochemical syntheses of 125I-cRGD-USPIO were accomplished with a radiochemical purity of 96.05 ± 0.33 %. High radiochemical stability was found in fresh human serum and in phosphate-buffered saline. The average hydrodynamic size of 125I-cRGD-USPIO determined by dynamic light scattering was 51.3 nm. Results of in vitro experiments verified the specificity of the radiolabeled nanoparticles to tumor cells. Preliminary biodistribution studies of 125I-radiolabeled cRGD-USPIO in Bcap37-bearing nude mice showed that it had long circulation half-life, high tumor uptake, and high initial blood retention with moderate liver uptake. In vivo tumor targeting and uptake of the radiolabeled nanoparticles in mice model were visualized by SPECT and MRI collected at different time points. Our results strongly indicated that the 125I-cRGD-USPIO could be used as a promising bifunctional radiotracer for early clinical tumor detection with high sensitivity and high spatial resolution by SPECT and MRI.

An improved radiosynthesis of O-(2-[18 F]fluoroethyl)-O-(p-nitrophenyl)methylphosphonate: A first-in-class cholinesterase PET tracer.

PubMed

Neumann, Kiel D; Thompson, Charles M; Blecha, Joseph E; Gerdes, John M; VanBrocklin, Henry F

2017-06-15

O-(2-Fluoroethyl)-O-(p-nitrophenyl) methylphosphonate 1 is an organophosphate cholinesterase inhibitor that creates a phosphonyl-serine covalent adduct at the enzyme active site blocking cholinesterase activity in vivo. The corresponding radiolabeled O-(2-[ 18 F]fluoroethyl)-O-(p-nitrophenyl) methylphosphonate, [ 18 F]1, has been previously prepared and found to be an excellent positron emission tomography imaging tracer for assessment of cholinesterases in live brain, peripheral tissues, and blood. However, the previously reported [ 18 F]1 tracer synthesis was slow even with microwave acceleration, required high-performance liquid chromatography separation of the tracer from impurities, and gave less optimal radiochemical yields. In this paper, we report a new synthetic approach to circumvent these shortcomings that is reliant on the facile reactivity of bis-(O,O-p-nitrophenyl) methylphosphonate, 2, with 2-fluoroethanol in the presence of DBU. The cold synthesis was successfully translated to provide a more robust radiosynthesis. Using this new strategy, the desired tracer, [ 18 F]1, was obtained in a non-decay-corrected radiochemical yield of 8 ± 2% (n = 7) in >99% radiochemical and >95% chemical purity with a specific activity of 3174 ± 345 Ci/mmol (EOS). This new facile radiosynthesis routinely affords highly pure quantities of [ 18 F]1, which will further enable tracer development of OP cholinesterase inhibitors and their evaluation in vivo. Copyright © 2017 John Wiley & Sons, Ltd.

Radiochemical method of removing flocculant polymers from washery water

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

Gerasimova, G.I.; Malysheva, N.G.; Starchik, L.P.

1977-01-01

Research data are presented on the destruction of flocculant polymers in washery water by irradiation. High-energy radiation destroys various polymers (PAA, POE, Metas, Kometa, etc.) and the treated water can be recycled.

78 FR 33836 - CPSC Safety Academy

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-05

... compliance issues, and the fast track recall program. The Safety Academy is structured such that the morning... continued, including Fast Track and Section 15; and (Panel 3) Flammable Fabrics, Drawstrings, and Sleepwear...

"Chew on This": An Interview with Charles Wilson

ERIC Educational Resources Information Center

Curriculum Review, 2007

2007-01-01

When the award-winning journalist Eric Schlosser's groundbreaking book "Fast Food Nation" was published for adults, many called for his insights and research to be shared with young readers. And, when "Fast Food Nation" gained popularity as a fictional, yet factual motion picture, the buzz continued. Children, after all, are the fast-food…

Conversion of Radio-Frequency Pulses to Continuous-Wave Sinusoids by Fast Switching and Narrowband Filtering

DTIC Science & Technology

2016-09-01

Switching and Narrowband Filtering by Gregory J Mazzaro, Andrew J Sherbondy, Kenneth I Ranney, and Kelly D Sherbondy...Switching and Narrowband Filtering by Gregory J Mazzaro, Andrew J Sherbondy, Kenneth I Ranney, and Kelly D Sherbondy Sensors and Electron Devices...08/2016 4. TITLE AND SUBTITLE Conversion of Radio-Frequency Pulses to Continuous-Wave Sinusoids by Fast Switching and Narrowband Filtering 5a

Digital microfluidic platform for radiochemistry

DOEpatents

Van Dam, Michael R.; Kim, Chang-Jin; Chen, Supin; Ding, Huijiang; Shah, Gaurav Jitendra; Keng, Pei Yuin

2016-11-01

Disclosed herein are methods of performing microchemical reactions and electro-wetting-on-dielectric devices (EWOD devices) for use in performing those reactions. These devices and method are particularly suited for preparing radiochemical compounds, particularly compounds containing .sup.18F.

Digital microfluidic platform for radiochemistry

DOEpatents

Van Dam, R. Michael; Kim, Chang -Jin; Chen, Supin; Ding, Huijiang; Shah, Gaurav Jitendra; Keng, Pei Yuin

2015-11-24

Disclosed herein are methods of performing microchemical reactions and electro-wetting-on-dielectric devices (EWOD devices) for use in performing those reactions. These devices and method are particularly suited for preparing radiochemical compounds, particularly compounds containing .sup.18F.

A convenient route to [68Ga]Ga-MAA for use as a particulate PET perfusion tracer.

PubMed

Mathias, Carla J; Green, Mark A

2008-12-01

A convenient method is described for compounding [(68)Ga]Ga-MAA (MAA=macroaggregated human serum albumin) with the eluate of a commercially available TiO(2)-based (68)Ge/(68)Ga generator. The final [(68)Ga]Ga-MAA product was obtained with an 81.6+/-5.3% decay-corrected radiochemical yield and a radiochemical purity of 99.8+/-0.1% (n=5). Microscopic examination showed the [(68)Ga]Ga-MAA product to remain within the original particle size range. The entire procedure, from generator elution to delivery of the final [(68)Ga]Ga-MAA suspension, could be completed in 25 min. Only 4.4+/-0.9% of the total (68)Ge breakthrough remaining associated with the final [(68)Ga]Ga-MAA product. The procedure allows reasonably convenient preparation of [(68)Ga]Ga-MAA in a fashion that can be readily adapted to sterile product compounding for human use.

New Opportunity for Improved Nuclear Forensics, Radiochemical Diagnostics, and Nuclear Astrophysics: Need for a Total-Cross-Section Apparatus at the LANSCE

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

Koehler, Paul E.; Hayes-Sterbenz, Anna C.; Bredeweg, Todd Allen

Total-cross-section measurements are feasible on a much wider range of radioactive samples than (n,γ) cross-section measurements, and information extracted from the former can be used to set tight constraints on the latter. There are many (n,γ) cross sections of great interest to radiochemical diagnostics, nuclear forensics, and nuclear astrophysics which are beyond the reach of current direct measurement, that could be obtained in this way. Our simulations indicate that measurements can be made at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center for samples as small as 10μg. There are at least 40 high-interestmore » nuclides which should be measurable, including 88Y, 167,168,170,171Tm, 173,174Lu, and 189,190,192Ir.« less

Preparing for Harvesting Radioisotopes from FRIB

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

Lapi, Suzanne

2015-11-30

In the second quarter of this grant, work has progressed smoothly at all three collaborating institutions. We have recently completed our first experiment at the NSCL under this grant successfully, where 79Kr was collected by cryotrapping from our water target apparatus. The three PI’s, one undergraduate (Boone Marois), two graduate students (Stacy Queern and Matt Scott) and one post-doc (Aranh Pen) were assisted by Dave Morrissey at the NSCL to perform this experiment. The experiment also provided the opportunity for a collaboration meeting of the PI’s to discuss future work on this proposal. Significant progress has been made on bothmore » novel radiochemical separations technology at the University of Missouri, and validating a radiochemical separation procedure for 48V at Washington University. The only change in the work-scope of the original proposal is the transition of the Washington University PI to the University of Alabama at Birmingham.« less

Radiolabeling of multimeric neurotensin(8-13) analogs with the short-lived positron emitter fluorine-18.

PubMed

Hultsch, Christina; Berndt, Mathias; Bergmann, Ralf; Wuest, Frank

2007-07-01

Three methods for (18)F-labeling of dimeric and tetrameric neurotensin(8-13) derivatives were evaluated with respect to the labeling yield and the required peptide amounts. Labeling using N-succinimidyl-4-[(18)F]fluorobenzoate ([(18)F]SFB) gave low radiochemical yield for the dimeric peptides. Coupling of the tetramer with [(18)F]SFB was not successful. High yields were obtained for labeling of the aminooxy-functionalized neurotensin(8-13) dimer using 4-[(18)F]fluorobenzaldehyde ([(18)F]FBA) whilst coupling of the corresponding tetramer gave only low yields. Labeling of sulfydryl-functionalized neurotensin(8-13) derivatives using the maleinimide 4-[(18)F]fluorobenzaldehyde-O-[6-(2,5-dioxo-2,5-dihydro-pyrrol-1-yl)-hexyl]-oxime ([(18)F]FBAM) resulted in high radiochemical yields for both, the dimer and the tetramer. Therefore, [(18)F]FBAM seems to be the most suitable (18)F-labeling agent for multivalent neurotensin(8-13) derivatives.

Radiolabelling of isopeptide N epsilon-(gamma-glutamyl)-L-lysine by conjugation with N-succinimidyl-4-[18F]fluorobenzoate.

PubMed

Wüst, F; Hultsch, C; Bergmann, R; Johannsen, B; Henle, T

2003-07-01

The isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine 4 was labelled with 18F via N-succinimidyl-4-[18F]fluorobenzoate ([18F]SFB). A modified approach for the convenient synthesis of [18F]SFB was used, and [18F]SFB could be obtained in decay-corrected radiochemical yields of 44-53% (n = 20) and radiochemical purity >95% within 40 min after EOB. For labelling N(epsilon)-(gamma-glutamyl)-L-lysine with [18F]SFB the effects of isopeptide concentration, temperature, and pH were studied to determine the optimum reaction conditions. The coupling reaction was shown to be temperature and pH independent while being strongly affected by the isopeptide concentration. Using the optimized labelling conditions, in a typical experiment 1.3GBq of [18F]SFB could be converted into 447MBq (46%, decay-corrected) of [18F]fluorobenzoylated isopeptide within 45 min, including HPLC purification.

Carbon-11 choline: synthesis, purification, and brain uptake inhibition by 2-dimethylaminoethanol

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

Rosen, M.A.; Jones, R.M.; Yano, Y.

We report an improved method for the synthesis and purification of (11C)methylcholine from the precursors (11C)methyliodide and 2-dimethylaminoethanol (deanol). Preparation time, including purification, is 35 min postbombardment. Forty millicuries of purified injectable (11C)choline were produced with a measured specific activity of greater than 300 Ci/mmol and a radiochemical purity greater than 98%. The decay corrected radiochemical yield for the synthesis and purification was approximately 50%. Residual precursor deanol, which inhibits brain uptake of choline, is removed by a rapid preparative high performance liquid chromatography (HPLC) method using a reverse phase cyano column with a biologically compatible 100% water eluent. Evaporationmore » alone did not completely remove the deanol precursor. Brain uptake of the (11C)choline product was six times greater after HPLC removal of deanol because doses of less than 1 microgram/kg significantly inhibit (14C)choline brain uptake.« less

Development and Preliminary Evaluation of TFIB, a New Bimodal Prosthetic Group for Bioactive Molecule Labeling.

PubMed

Billaud, Emilie M F; Vidal, Aurélien; Vincenot, Amélie; Besse, Sophie; Bouchon, Bernadette; Debiton, Eric; Miot-Noirault, Elisabeth; Miladi, Imen; Rbah-Vidal, Latifa; Auzeloux, Philippe; Chezal, Jean-Michel

2015-02-12

The new readily available prosthetic group, tetrafluorophenyl 4-fluoro-3-iodobenzoate (TFIB), designed for both molecular imaging and targeted radionuclide therapy purposes was radiolabeled either with fluorine or iodine radionuclides with excellent radiochemical yields and purities. These radiolabeled tags were conjugated to N,N-diethylethylenediamine to give melanin-targeting radiotracers [ (125) I]9 and [ (18) F]9, which were successfully evaluated by PET and gamma scintigraphic imaging in B16F0 pigmented melanoma-bearing C57BL/6J mice. Then, radiolabeled [ (125) I]/[ (18) F]TFIB was used to tag tumor-targeting peptides (i.e., PEG3[c(RGDyK)]2 and NDP-MSH targeting αvβ3 integrin and MC1R receptors, respectively) in mild conditions and with good radiochemical yields (47-83% d.c.) and purities (>99%). The resulting radiolabeled peptides were assessed both in vitro and by PET imaging in animal models.

Development and Preliminary Evaluation of TFIB, a New Bimodal Prosthetic Group for Bioactive Molecule Labeling

PubMed Central

2014-01-01

The new readily available prosthetic group, tetrafluorophenyl 4-fluoro-3-iodobenzoate (TFIB), designed for both molecular imaging and targeted radionuclide therapy purposes was radiolabeled either with fluorine or iodine radionuclides with excellent radiochemical yields and purities. These radiolabeled tags were conjugated to N,N-diethylethylenediamine to give melanin-targeting radiotracers [125I]9 and [18F]9, which were successfully evaluated by PET and gamma scintigraphic imaging in B16F0 pigmented melanoma-bearing C57BL/6J mice. Then, radiolabeled [125I]/[18F]TFIB was used to tag tumor-targeting peptides (i.e., PEG3[c(RGDyK)]2 and NDP-MSH targeting αvβ3 integrin and MC1R receptors, respectively) in mild conditions and with good radiochemical yields (47–83% d.c.) and purities (>99%). The resulting radiolabeled peptides were assessed both in vitro and by PET imaging in animal models. PMID:25699145

Annual Report, Fall 2016: Identifying Cost Effective Tank Waste Characterization Approaches

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

Reboul, S. H.; DiPrete, D. P.

2016-12-12

This report documents the activities that were performed during the second year of a project undertaken to improve the cost effectiveness and timeliness of SRNL’s tank closure characterization practices. The activities performed during the first year of the project were previously reported in SRNL-STI-2015-00144. The scope of the second year activities was divided into the following three primary tasks: 1) develop a technical basis and strategy for improving the cost effectiveness and schedule of SRNL’s tank closure characterization program; 2) initiate the design and assembly of a new waste removal system for improving the throughput and reducing the personnel dosemore » associated with extraction chromatography radiochemical separations; and 3) develop and perform feasibility testing of three alternative radiochemical separation protocols holding promise for improving high resource demand/time consuming tank closure sample analysis methods.« less

Large-scale purification of 90Sr from nuclear waste materials for production of 90Y, a therapeutic medical radioisotope.

PubMed

Wester, Dennis W; Steele, Richard T; Rinehart, Donald E; DesChane, Jaquetta R; Carson, Katharine J; Rapko, Brian M; Tenforde, Thomas S

2003-07-01

A major limitation on the supply of the short-lived medical isotope 90Y (t1/2 = 64 h) is the available quantity of highly purified 90Sr generator material. A radiochemical production campaign was therefore undertaken to purify 1,500 Ci of 90Sr that had been isolated from fission waste materials. A series of alkaline precipitation steps removed all detectable traces of 137Cs, alpha emitters, and uranium and transuranic elements. Technical obstacles such as the buildup of gas pressure generated upon mixing large quantities of acid with solid 90Sr carbonate were overcome through safety features incorporated into the custom-built equipment used for 90Sr purification. Methods are described for analyzing the chemical and radiochemical purity of the final product and for accurately determining by gravimetry the quantities of 90Sr immobilized on stainless steel filters for future use.

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

Not Available

This volume contains the interim change notice for sample preparation methods. Covered are: acid digestion for metals analysis, fusion of Hanford tank waste solids, water leach of sludges/soils/other solids, extraction procedure toxicity (simulate leach in landfill), sample preparation for gamma spectroscopy, acid digestion for radiochemical analysis, leach preparation of solids for free cyanide analysis, aqueous leach of solids for anion analysis, microwave digestion of glasses and slurries for ICP/MS, toxicity characteristic leaching extraction for inorganics, leach/dissolution of activated metal for radiochemical analysis, extraction of single-shell tank (SST) samples for semi-VOC analysis, preparation and cleanup of hydrocarbon- containing samples for VOCmore » and semi-VOC analysis, receiving of waste tank samples in onsite transfer cask, receipt and inspection of SST samples, receipt and extrusion of core samples at 325A shielded facility, cleaning and shipping of waste tank samplers, homogenization of solutions/slurries/sludges, and test sample preparation for bioassay quality control program.« less

Synthesis and biological assessment of folate-accepted developer (99m)Tc-DTPA-folate-polymer.

PubMed

Chen, Fei; Shao, Kejing; Zhu, Bao; Jiang, Mengjun

2016-05-15

A novel cancer-targetable folate-poly(2-hydroxyethyl methacrylate) (PFDH) copolymer containing DTPA segment was prepared by conventional chemical synthesis and labeled with (99m)Tc subsequently. The (99m)Tc-labled PFDH could be produced easily with high radiochemical yield of 91% and radiochemical purity of 95%. The LogP octanol-water value for the (99m)Tc-labled PFDH was -2.19 and the radiotracer was stable in phosphate-buffered saline and human serum for 2h (>95% in PBS or ∼90% in human serum). To investigate (99m)Tc-labled PFDH tumor targeting, the in vitro and in vivo stability, cell uptake, in vivo biodistribution, and SPECT imaging were evaluated, respectively. These preliminary results strongly suggest that the novel folate conjugated dendrimer maybe developed to be potential for delivery of therapeutic radionuclides. Copyright © 2016 Elsevier Ltd. All rights reserved.

Measurements of 55Fe activity in activated steel samples with GEMPix

NASA Astrophysics Data System (ADS)

Curioni, A.; Dinar, N.; La Torre, F. P.; Leidner, J.; Murtas, F.; Puddu, S.; Silari, M.

2017-03-01

In this paper we present a novel method, based on the recently developed GEMPix detector, to measure the 55Fe content in samples of metallic material activated during operation of CERN accelerators and experimental facilities. The GEMPix, a gas detector with highly pixelated read-out, has been obtained by coupling a triple Gas Electron Multiplier (GEM) to a quad Timepix ASIC. Sample preparation, measurements performed on 45 samples and data analysis are described. The calibration factor (counts per second per unit specific activity) has been obtained via measurements of the 55Fe activity determined by radiochemical analysis of the same samples. Detection limit and sensitivity to the current Swiss exemption limit are calculated. Comparison with radiochemical analysis shows inconsistency for the sensitivity for only two samples, most likely due to underestimated uncertainties of the GEMPix analysis. An operative test phase of this technique is already planned at CERN.

Debris characterization diagnostic for the NIF

NASA Astrophysics Data System (ADS)

Miller, M. C.; Celeste, J. R.; Stoyer, M. A.; Suter, L. J.; Tobin, M. T.; Grun, J.; Davis, J. F.; Barnes, C. W.; Wilson, D. C.

2001-01-01

Generation of debris from targets and by x-ray ablation of surrounding materials will be a matter of concern for experimenters and National Ignition Facility (NIF) operations. Target chamber and final optics protection, for example debris shield damage, drive the interest for NIF operations. Experimenters are primarily concerned with diagnostic survivability, separation of mechanical versus radiation induced test object response in the case of effects tests, and radiation transport through the debris field when the net radiation output is used to benchmark computer codes. In addition, radiochemical analysis of activated capsule debris during ignition shots can provide a measure of the ablator <ρr>. Conceptual design of the Debris Monitor and Rad-Chem Station, one of the NIF core diagnostics, is presented. Methods of debris collection, particle size and mass analysis, impulse measurement, and radiochemical analysis are given. A description of recent experiments involving debris collection and impulse measurement on the OMEGA and Pharos lasers is also provided.

Validation of a [Al18F]PSMA-11 preparation for clinical applications.

PubMed

Al-Momani, Ehab; Israel, Ina; Samnick, Samuel

2017-12-01

Imaging prostate-specific membrane antigen (PSMA) using positron emission tomography (PET) has been presented so far as the most sensitive and specific with regard to prostate cancer detection, in particular in high-risk prostate cancer patients. Currently, it mainly features Gallium-68 ( 68 Ga) labeled PSMA ligands, notably [ 68 Ga]Glu-urea-Lys(Ahx)-HBED-CC ([ 68 Ga]-PSMA-11) and [ 68 Ga]DOTAGA-FFK (Sub-KuE termed ([ 68 Ga]PSMA-I&T). However, 68 Ga has several shortcomings as radionuclide including a short half-life and non-ideal energies. This has motivated consideration of 18 F-labeled analogues for PET imaging of prostate cancer. Here, we describe a simple synthesis and validation of a fluorine-18 labeled Glu-urea-Lys(Ahx)-HBED-CC ([Al 18 F]PSMA-11) for nuclear medicine applications. An efficient method for preparation of [Al 18 F]PSMA-11 was developed and validated (according to Pharm Eur) for routinely clinical applications. [Al 18 F]PSMA-11 was reproducibly obtained in radiochemical yields of 84 ± 6% (n = 15) and > 98% radiochemical purity using an improved one-step radiofluorination in aqueous solution. The total (production/preparation) time, including purification, pharmacological formulation of the isolated product and the quality control of the injectable solution was less than 60min. The [Al 18 F]PSMA-11 was stable over 4h in 1% EtOH/saline selected as injection solution. The solution was sterile, non-pyrogenic and ready for clinical applications after sterile filtration through a 0.22µm membrane filter under sterile conditions. In addition, [Al 18 F]PSMA-11 exhibited higher uptake and retention in PMSA-expressing LNCap prostate cells as compared to its clinically established 68 Ga-labeled analogues [ 68 Ga]PSMA-11 and [ 68 Ga]PSMA-I&T as well as to [ 68 Ga]NOTA-Bn-PSMA. The simple and fast preparation of [Al 18 F]PSMA-11 combined with its favorable pharmacological properties warrant its translation to a clinical setting. The facile and high-yielding radiosynthesis of [Al 18 F]PSMA-11as well as its promising in vitro and in-vivo characteristics makes it worthy of clinical development for PET imaging of prostate cancer. Copyright © 2017. Published by Elsevier Ltd.

Development of Meharry Medical College Prostate Cancer Research Program

DTIC Science & Technology

2010-03-01

breakfast until their blood was drawn the next morning before 9:00 a.m. by a certified phlebotomist/registered nurse. 30 ml fasting venous blood was drawn...for each participnats. Participants were asked to return the next day without taking breakfast , and at the second visit 30 ml fasting venous blood...Ogunkua continue to develop their research laboratories with great success. They have independent funding and their laboratory continues to grow to

Automated Synthesis of 18F-Fluoropropoxytryptophan for Amino Acid Transporter System Imaging

PubMed Central

Shih, I-Hong; Duan, Xu-Dong; Kong, Fan-Lin; Williams, Michael D.; Zhang, Yin-Han; Yang, David J.

2014-01-01

Objective. This study was to develop a cGMP grade of [18F]fluoropropoxytryptophan (18F-FTP) to assess tryptophan transporters using an automated synthesizer. Methods. Tosylpropoxytryptophan (Ts-TP) was reacted with K18F/kryptofix complex. After column purification, solvent evaporation, and hydrolysis, the identity and purity of the product were validated by radio-TLC (1M-ammonium acetate : methanol = 4 : 1) and HPLC (C-18 column, methanol : water = 7 : 3) analyses. In vitro cellular uptake of 18F-FTP and 18F-FDG was performed in human prostate cancer cells. PET imaging studies were performed with 18F-FTP and 18F-FDG in prostate and small cell lung tumor-bearing mice (3.7 MBq/mouse, iv). Results. Radio-TLC and HPLC analyses of 18F-FTP showed that the Rf and Rt values were 0.9 and 9 min, respectively. Radiochemical purity was >99%. The radiochemical yield was 37.7% (EOS 90 min, decay corrected). Cellular uptake of 18F-FTP and 18F-FDG showed enhanced uptake as a function of incubation time. PET imaging studies showed that 18F-FTP had less tumor uptake than 18F-FDG in prostate cancer model. However, 18F-FTP had more uptake than 18F-FDG in small cell lung cancer model. Conclusion. 18F-FTP could be synthesized with high radiochemical yield. Assessment of upregulated transporters activity by 18F-FTP may provide potential applications in differential diagnosis and prediction of early treatment response. PMID:25136592

Automated synthesis of 18F-fluoropropoxytryptophan for amino acid transporter system imaging.

PubMed

Shih, I-Hong; Duan, Xu-Dong; Kong, Fan-Lin; Williams, Michael D; Yang, Kevin; Zhang, Yin-Han; Yang, David J

2014-01-01

This study was to develop a cGMP grade of [(18)F]fluoropropoxytryptophan ((18)F-FTP) to assess tryptophan transporters using an automated synthesizer. Tosylpropoxytryptophan (Ts-TP) was reacted with K(18)F/kryptofix complex. After column purification, solvent evaporation, and hydrolysis, the identity and purity of the product were validated by radio-TLC (1M-ammonium acetate : methanol = 4 : 1) and HPLC (C-18 column, methanol : water = 7 : 3) analyses. In vitro cellular uptake of (18)F-FTP and (18)F-FDG was performed in human prostate cancer cells. PET imaging studies were performed with (18)F-FTP and (18)F-FDG in prostate and small cell lung tumor-bearing mice (3.7 MBq/mouse, iv). Radio-TLC and HPLC analyses of (18)F-FTP showed that the Rf and Rt values were 0.9 and 9 min, respectively. Radiochemical purity was >99%. The radiochemical yield was 37.7% (EOS 90 min, decay corrected). Cellular uptake of (18)F-FTP and (18)F-FDG showed enhanced uptake as a function of incubation time. PET imaging studies showed that (18)F-FTP had less tumor uptake than (18)F-FDG in prostate cancer model. However, (18)F-FTP had more uptake than (18)F-FDG in small cell lung cancer model. (18)F-FTP could be synthesized with high radiochemical yield. Assessment of upregulated transporters activity by (18)F-FTP may provide potential applications in differential diagnosis and prediction of early treatment response.

Radiochemical methodology for the determination of the mass balance of suspended particulate materials exchanged at the inlets of the Venice Lagoon

NASA Astrophysics Data System (ADS)

Degetto, S.; Cantaluppi, C.

2004-11-01

The Venice Lagoon is connected to the Adriatic Sea by three inlets, with an average daily water inflow of 345∗10 6 m 3. Due to the diversion of the major rivers out of the lagoon (done in the past centuries), the sediment supply from the drainage basin is now very low when compared to the amount of sediment exchanged at the inlets (<1%). The limited sediment supply and the combined action of natural and anthropic pressures (e.g. waves, ships, fishing activities, dredging for navigation purposes) have caused in the last few decades a significant erosion of mudflats and salt-marshes. In order to investigate the history and the characteristics of the above phenomenon, with particular regard to the most recent years and the future trend, a wide radiochemical survey has been carried out in the whole lagoon, including the characterisation of the suspended particulate matter entering and leaving the lagoon in different tidal and meteorological conditions, with the aim of obtaining an indirect estimate of the sediment mass balance of the lagoon. The proposed radiochemical methodology, which is based on concentration measurements of airborne radionuclides in suspended particulate matter, appears to be an useful alternative to direct methods (e.g. bathymetric campaigns in the lagoon or mass fluxes measurements of the suspended particulate materials exchanged at the inlets). The results obtained, which show a complex sedimentary situation, highlight the erosion acting in some central and southern lagoon areas but recognise also the present accumulation phase coming into view in the northern lagoon.

The strange case of the [13N]NH3: validation of the production process for human use.

PubMed

Statuto, Massimo; Galli, Elisa; Bertagna, Francesco; Migliorati, Elena; Zanella, Isabella; Di Lorenzo, Diego; De Agostini, Antonio; Rodella, Carlo; Apostoli, Pietro; Caimi, Luigi; Giubbini, Raffaele; Biasiotto, Giorgio

2016-04-01

PET radiopharmaceuticals are often injected in patients before all quality controls are performed and before sterility results are available. We propose a process validation to produce very safe and pure [N]NH3 for human use. [N]NH3 was produced in the cyclotron target. Online purification was performed by anionic exchange resin. All the production steps were subjected to a sterility test. Some additional controls were added to those required by the monograph. The radiochemical yield of the syntheses was 26.3 and 61.5% corrected for decay, with a radiochemical purity of 100%. In addition to quality controls requested by the European Pharmacopeia monograph, we carefully analyzed the product for the presence of possible contaminants. Some elements, mainly metals, were found in very low amounts at concentrations in the range of ppb. The radionuclidic purity was verified. The achievement of the parameters of osmolality, by addition of saline solution to the preparation, made the analysis of chemical purity difficult and worsened the measurement of radiochemical purity by high performance liquid chromatography. Only pH control is necessary before administration to patients and therefore a safe production process was set up to prevent microbiological contamination. All phases were carefully standardized, starting from in-target production of [N]NH3, to final splitting in the syringes. Sterility tests showed no bacterial growth, indicating the safety of the production process. All our syntheses followed the monograph indications and were optimal to obtain PET imaging of a patient's myocardium.

SAMPLING AND ANALYSIS OF POTENTIAL GEOTHERMAL SITES

EPA Science Inventory

This document contains general information on the physical, chemical and radiochemical data of geothermal manifestations (wells and springs) in areas with the most probable potential for development. Information contained in this document, together with other existing data, can b...

Routine production of [(18)f]flumazenil from iodonium tosylate using a sample pretreatment method: a 2.5-year production report.

PubMed

Moon, Byung Seok; Park, Jun Hyung; Lee, Hong Jin; Lee, Byung Chul; Kim, Sang Eun

2014-10-01

[(18)F]Flumazenil, which has the advantage of a longer half-life than [(11)C]flumazenil, is well known for determining of the central benzodiazepine receptor concentrations. However, [(18)F]flumazenil has not been widely used because fluctuating and relatively low yields render automatic production insufficient for routine and multicenter clinical trials. Here, we describe the results of a 2.5-year production study of [(18)F]flumazenil using an iodonium tosylate precursor, which allowed us to overcome the limitations of low and fluctuating radiochemical yields. We developed a clinically applicable production system by modifying a commercial synthesizer for the reliable and reproducible production of [(18)F]flumazenil for routine clinical studies. [(18)F]Flumazenil was prepared at 150 °C for 5 min in the presence of 4-methylphenyl-mazenil iodonium tosylate (4 mg), a radical scavenger (TEMPO, 1 mg), and [(18)F]KF/kryptofix 2.2.2 complex in N,N-dimethylformamide (1 ml). In the purification step, the final mixture was pretreated using different cartridges before performing high-performance liquid chromatography (HPLC) separation. Finally, we measured the radiochemical yield and performed quality-control assays on 94 batches. After carrying out additional purification before HPLC separation using a C18 plus Sep-Pak cartridge, the radiochemical yield of [(18)F]flumazenil increased from 34.4 ± 9.7 % (without the pretreatment, n = 24) to 53.4 ± 9.0 % (n = 94), and the lifetime of the semi-preparative column was five times that of the column without the C18 plus Sep-Pak cartridge. The mean-specific activity of [(18)F]flumazenil was 572 ± 116 GBq/μmol at the end of synthesis, and the radiochemical purity was more than 99 %, as determined by analytical HPLC and radio-TLC. [(18)F]Flumazenil prepared using this method satisfied all quality-control test standards and was highly stable for up to 6 h after preparation. The results of the 2.5-year production study using an iodonium tosylate precursor indicate that [(18)F]flumazenil has commercial and routine clinical applicability.

Effects of radiolysis on yttrium-90-labeled Lym-1 antibody preparations.

PubMed

Salako, Q A; O'Donnell, R T; DeNardo, S J

1998-04-01

The physical half-life of 2.6 days and 2.2 MeV beta emissions of 90Y provide excellent properties for radioimmunotherapy applications. However, the clinically useful beta particles may be a source of radiation-induced damage of 90Y-labeled immunoconjugate radiopharmaceuticals during preparation or short-term storage. The stability of 90Y-labeled Lym-1 antibody was studied in standard radiopharmacy conditions to establish a formulation at which radiolysis is not a problem. Lym-1-21T-BAD immunoconjugate intermediate was prepared according to our standard procedure, then labeled with 90Y at 1, 2, 4 and 9.4 mCi/mg Lym-1 using 0.5 M tetramethylammonium acetate, pH 7, labeling buffer. Each mixture was challenged in diethylenetriaminepentaacetic acid to remove nonspecifically bound 90Y. The 90Y-21T-BAD-Lym-1 products were purified by centrifuged molecular sieving column chromatography. The radiochemical purity and immunoreactivity of each preparation was monitored daily by high-performance liquid chromatography (HPLC) and solid-phase radioimmunoassay, respectively, for 3 days. The preparation at 2 mCi/mg was also formulated in 4% (wt/vol) human serum albumin (HSA) overall and at 9.4 mCi/mg in five-fold water, 4 and 10% (wt/vol) HSA overall; all were monitored as above. The monomeric quality and purity profile of products at 1 and 2 mCi/mg were retained (> or = 80%) as was their immunoreactivity (> or = 75%) over 3 days. The radiochemical purity and immunoreactivity of the product at 4 mCi/mg declined to 65% and 28%, respectively, by 3 days after preparation and in just 48 hr, the product at 9.4 mCi/mg had degraded to 21% in radiochemical purity with only 3% immunoreactivity. The current HPLC data and earlier published chromatographic evidence did not support a compromised radiochemical integrity of 90Y-DOTA complexes by loss of 90Y from the DOTA chelate. Radiolysis of 90Y-labeled antibody preparations did not appear to be a problem at 90Y-21T-BAD-Lym-1 products < or = 2 mCi/mg. Human serum albumin proved to be an effective radioprotectant as the initial 100% immunoreactivity of the product at 2 mCi/mg was retained for 72 hr. The results underscore the need for appropriate formulations and dilutions of clinical doses of 90Y immunopharmaceuticals immediately after manufacture.

A scheme for recording a fast process at nanosecond scale by using digital holographic interferometry with continuous wave laser

NASA Astrophysics Data System (ADS)

Wang, Jun; Zhao, Jianlin; Di, Jianglei; Jiang, Biqiang

2015-04-01

A scheme for recording fast process at nanosecond scale by using digital holographic interferometry with continuous wave (CW) laser is described and demonstrated experimentally, which employs delayed-time fibers and angular multiplexing technique and can realize the variable temporal resolution at nanosecond scale and different measured depths of object field at certain temporal resolution. The actual delay-time is controlled by two delayed-time fibers with different lengths. The object field information in two different states can be simultaneously recorded in a composite hologram. This scheme is also suitable for recording fast process at picosecond scale, by using an electro-optic modulator.

Frequency tagging to track the neural processing of contrast in fast, continuous sound sequences.

PubMed

Nozaradan, Sylvie; Mouraux, André; Cousineau, Marion

2017-07-01

The human auditory system presents a remarkable ability to detect rapid changes in fast, continuous acoustic sequences, as best illustrated in speech and music. However, the neural processing of rapid auditory contrast remains largely unclear, probably due to the lack of methods to objectively dissociate the response components specifically related to the contrast from the other components in response to the sequence of fast continuous sounds. To overcome this issue, we tested a novel use of the frequency-tagging approach allowing contrast-specific neural responses to be tracked based on their expected frequencies. The EEG was recorded while participants listened to 40-s sequences of sounds presented at 8Hz. A tone or interaural time contrast was embedded every fifth sound (AAAAB), such that a response observed in the EEG at exactly 8 Hz/5 (1.6 Hz) or harmonics should be the signature of contrast processing by neural populations. Contrast-related responses were successfully identified, even in the case of very fine contrasts. Moreover, analysis of the time course of the responses revealed a stable amplitude over repetitions of the AAAAB patterns in the sequence, except for the response to perceptually salient contrasts that showed a buildup and decay across repetitions of the sounds. Overall, this new combination of frequency-tagging with an oddball design provides a valuable complement to the classic, transient, evoked potentials approach, especially in the context of rapid auditory information. Specifically, we provide objective evidence on the neural processing of contrast embedded in fast, continuous sound sequences. NEW & NOTEWORTHY Recent theories suggest that the basis of neurodevelopmental auditory disorders such as dyslexia might be an impaired processing of fast auditory changes, highlighting how the encoding of rapid acoustic information is critical for auditory communication. Here, we present a novel electrophysiological approach to capture in humans neural markers of contrasts in fast continuous tone sequences. Contrast-specific responses were successfully identified, even for very fine contrasts, providing direct insight on the encoding of rapid auditory information. Copyright © 2017 the American Physiological Society.

Synthesis and evaluation of a 99mTc-labeled tubulin-binding agent for tumor imaging.

PubMed

Erfani, Mostafa; Shamsaei, Mojtaba; Mohammadbaghery, Faiyaz; Shirmardi, Seyed Pezhman

2014-05-30

Cholchicine and its derivatives are very potent tubulin-binding compounds and can be used as a potential tumor targeting agents. In this study, colchicine was labeled with (99m) Tc via hydrazinonicotinic acid (HYNIC) and was investigated further. HYNIC/cholchicine was synthesized and labeling with (99m)Tc was performed at 95 °C for 15 min and radiochemical analysis included HPLC method. The stability of radiconjugate was checked in the presence of human serum at 37 °C up to 24 h. Biodistribution was studied in breast tumor-bearing mice. Labeling yield of 95.8 ± 0.54% was obtained corresponding to a specific activity of 54 MBq/µmol. Radioconjugate showed good stability in the presence of human serum. Biodistribution studies in tumor-bearing mice showed that (99m) Tc/HYNIC/colchicine conjugate accumulated in tumor with good uptake (3.17 ± 0.14% g/g at 1 h post-injection). The radioconjugate was cleared fast from normal organs and showed clearance through urinary and hepatobiliary systems with accumulation of activity in kidneys and intestine. This radioconjugate may be useful to assess the presence of tumor by imaging. Copyright © 2014 John Wiley & Sons, Ltd.

Hydrogen Safety Project: Chemical analysis support task. Window ``E`` analyses

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

Jones, T E; Campbell, J A; Hoppe, E W

1992-09-01

Core samples taken from tank 101-SY at Hanford during ``window E`` were analyzed for organic and radiochemical constituents by staff of the Analytical Chemistry Laboratory at Pacific Northwest Laboratory. Westinghouse Hanford company submitted these samples to the laboratory.

Sample Collection Information Document for Chemical & Radiochemical Analytes – Companion to Selected Analytical Methods for Environmental Remediation and Recovery (SAM) 2012

EPA Pesticide Factsheets

Sample Collection Information Document is intended to provide sampling information to be used during site assessment, remediation and clearance activities following a chemical or radiological contamination incident.

1981 Image II Conference Proceedings.

DTIC Science & Technology

1981-11-01

rapid motion of terrain detail across the display requires fast display processors. Other difficulties are perceptual: the visual displays must convey...has been a continuing effort by Vought in the last decade. Early systems were restricted by the unavailability of video bulk storage with fast random...each photograph. The calculations aided in the proper sequencing of the scanned scenes on the tape recorder and eventually facilitated fast random

Contamination of arctic Fjord sediments by Pb-Zn mining at Maarmorilik in central West Greenland.

PubMed

Perner, K; Leipe, Th; Dellwig, O; Kuijpers, A; Mikkelsen, N; Andersen, T J; Harff, J

2010-07-01

This study focuses on heavy metal contamination of arctic sediments from a small Fjord system adjacent to the Pb-Zn "Black Angel" mine (West Greenland) to investigate the temporal and spatial development of contamination and to provide baseline levels before the mines re-opening in January 2009. For this purpose we collected multi-cores along a transect from Affarlikassaa Fjord, which received high amounts of tailings from 1973 to 1990, to the mouth of Qaumarujuk Fjord. Along with radiochemical dating by (210)Pb and (137)Cs, geochemical analyses of heavy metals (e.g. As, Cd, Hg, Pb, and Zn) were carried out. Maximum contents were found at 12 cm depth in Affarlikassaa. After 17 years the mine last closed, specific local hydrographic conditions continue to disperse heavy metal enriched material derived from the Affarlikassaa into Qaumarujuk. Total Hg profiles from multi-cores along the transect clearly illustrate this transport and spatial distribution pattern of the contaminated material. Copyright 2010 Elsevier Ltd. All rights reserved.

Microfluidic 68Ga-labeling: a proof of principle study.

PubMed

Pfaff, Sarah; Philippe, Cecile; Pichler, Verena; Hacker, Marcus; Mitterhauser, Markus; Wadsak, Wolfgang

2018-05-01

Positron emission tomography (PET) as a tool for molecular imaging of cancer has gained huge interest in the last few years. Gallium-68 is a popular PET nuclide due to its favorable characteristics, like advantageous half-life (68 min) and independency of a cyclotron on-site for its production. Accordingly, several 68Ga-complexes for cancer imaging via PET have been made available during the last few years. In this work, 68Ga-labeled compounds were synthesized applying a commercially available microfluidic device for the first time. Therefore, a proof of principle study using three important radiotracers, [68Ga]Ga-PSMA-11, [68Ga]Ga-NODAGA-RGDyk and [68Ga]Ga-DOTA-NOC, was designed. For all three radioligands, various synthesis parameters were evaluated and the feasibility of using a continuous flow reactor was assessed. All of the precursors were successfully radiolabeled with a radiochemical yield higher than 80%, proving the principle that a microfluidic set-up is a suitable approach for the production of 68Ga-labeled tracers.

Iodination and stability of somatostatin analogues: comparison of iodination techniques. A practical overview.

PubMed

de Blois, Erik; Chan, Ho Sze; Breeman, Wouter A P

2012-01-01

For iodination ((125/127)I) of tyrosine-containing peptides, chloramin-T, Pre-Coated Iodo-Gen(®) tubes and Iodo-Beads(®) (Pierce) are commonly used for in vitro radioligand investigations and there have been reliant vendors hereof for decades. However, commercial availability of these radio-iodinated peptides is decreasing. For continuation of our research in this field we investigated and optimized (radio-)iodination of somatostatin analogues. In literature, radioiodination using here described somatostatin analogues and iodination techniques are described separately. Here we present an overview, including High Performance Liquid Chromatography (HPLC) separation and characterisation by mass spectrometry, to obtain mono- and di-iodinated analogues. Reaction kinetics of (125/127)I iodinated somatostatin analogues were investigated as function of reaction time and concentration of reactants, including somatostatin analogues, iodine and oxidizing agent. To our knowledge, for the here described somatostatin analogues, no (127)I iodination and optimization are described. (Radio-)iodinated somatostatin analogues could be preserved with a >90% radiochemical purity for 1 month after reversed phase HPLC-purification.

SEQUENTIAL RADIOCHEMICAL ANALYSIS FOR RUTHENIUM, STRONTIUM AND CESIUM IN ENVIRONMENTAL AIR

EPA Science Inventory

In routine surveillance operations, the radionuclide measurement of air discharged from an operating nuclear facility involves the entrainment of radionuclides on selective filter or absorptive media, and the determination of their gross beta activity. However, a more sensitive t...

Phosphorus Determination by Derivative Activation Analysis: A Multifaceted Radiochemical Application.

ERIC Educational Resources Information Center

Kleppinger, E. W.; And Others

1984-01-01

Although determination of phosphorus is important in biology, physiology, and environmental science, traditional gravimetric and colorimetric methods are cumbersome and lack the requisite sensitivity. Therefore, a derivative activation analysis method is suggested. Background information, procedures, and results are provided. (JN)

Fluxes of metals to a manganese nodule: Radiochemical, chemical, structural, and mineralogical studies

USGS Publications Warehouse

Moore, W.S.; Ku, T.-L.; Macdougall, J.D.; Burns, V.M.; Burns, R.; Dymond, J.; Lyle, M.W.; Piper, D.Z.

1981-01-01

Fluxes of metals to the top and bottom surfaces of a manganese nodule were determined by combining radiochemical (230Th, 231Pa, 232Th, 238U, 234U) and detailed chemical data. The top of the nodule had been growing in its collected orientation at 4.7 mm Myr-1 for at least 0.5 Myr and accreting Mn at 200 ??g cm-2 kyr-1. The bottom of the nodule had been growing in its collected orientation at about 12 mm Myr-1 for at least 0.3 Myr and accreting Mn at about 700 ??g cm-2 yr-1. Although the top of the nodule was enriched in iron relative to the bottom, the nodule had been accreting Fe 50% faster on the bottom. 232Th was also accumulating more rapidly in the bottom despite a 20-fold enrichment of 230Th on the top. The distribution of alpha-emitting nuclides calculated from detailed radiochemical measurements matched closely the pattern revealed by 109-day exposures of alpha-sensitive film to the nodule. However, the shape and slope of the total alpha profile with depth into the nodule was affected strongly by 226Ra and 222Rn migrations making the alpha-track technique alone an inadequate method of measuring nodule growth rates. Diffusion of radium in the nodule may have been affected by diagenetic reactions which produce barite, phillipsite and todorokite within 1 mm of the nodule surface; however, our sampling interval was too broad to document the effect. We have not been able to resolve the importance of nodule diagenesis on the gross chemistry of the nodule. ?? 1981.

Extra projection data identification method for fast-continuous-rotation industrial cone-beam CT.

PubMed

Yang, Min; Duan, Shengling; Duan, Jinghui; Wang, Xiaolong; Li, Xingdong; Meng, Fanyong; Zhang, Jianhai

2013-01-01

Fast-continuous-rotation is an effective measure to improve the scanning speed and decrease the radiation dose for cone-beam CT. However, because of acceleration and deceleration of the motor, as well as the response lag of the scanning control terminals to the host PC, uneven-distributed and redundant projections are inevitably created, which seriously decrease the quality of the reconstruction images. In this paper, we first analyzed the aspects of the theoretical sequence chart of the fast-continuous-rotation mode. Then, an optimized sequence chart was proposed by extending the rotation angle span to ensure the effective 2π-span projections were situated in the stable rotation stage. In order to match the rotation angle with the projection image accurately, structure similarity (SSIM) index was used as a control parameter for extraction of the effective projection sequence which was exactly the complete projection data for image reconstruction. The experimental results showed that SSIM based method had a high accuracy of projection view locating and was easy to realize.

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

None

The influence of alkaline earth metals on the distribution and excretion of strostium was studied in rats, sheep, and dairy cattle. The effects of dietary phosphorus and high levels of vitamin D on strontium distribution was observed. The influence of diuretics on potussium and cesium excretion was studied in sheep. Conventional and radiochemical procedures were used in studies of mineral metabolism in farm animals. Tracer studies are reported on copper- magnesium interrelationships in sheep; the calcium balance in sheep, swine, and steers as affected by stilbestrol, magnesium, ether extract, and zinc; and the relation of ccrtain blood plasma constituents tomore » milk in the dairy cow. Studies of the effects of radiation on reproduction were continued in cattle, swine, and rats. Standard psychological tests were applied to pre- and post-natally irradiated rats in an effort to assess the effects of radiation on various behavior characteristics. An effort is being made to develop similar techniques applicable to farm animals. Clinical, hematologic, and opthalmologic examinations were continued on burros exposed to fission weapon neutron-gamma irradiation. One burro was exposed to gamma-neutron radiation from a critical assembly in order to provide blood fur sodium activation analysis. Levels were compared wath human vaiues due to accidental exposure. Preliminary studies were initiated to study the role of water in the radiosensitivity of dormant seeds. The program of seed and plant irradiation was continued with the irradiation of 25 samples. (For preceding period see ORO-174.) (C.H.)« less

Analytical Chemistry Division annual progress report for period ending November 30, 1977

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

Lyon, W.S.

1978-03-01

Activities for the year are summarized in sections on analytical methodology, mass and mass emission spectrometry, analytical services, bio-organic analysis, nuclear and radiochemical analysis, and quality assurance and safety. Presentations of research results in publications and reports are tabulated. (JRD)

Development of Semiautomated Module for Preparation of 131I Labeled Lipiodol for Liver Cancer Therapy.

PubMed

Mukherjee, Archana; Subramanian, Suresh; Ambade, Rajwardhan; Avhad, Bhaurao; Dash, Ashutosh; Korde, Aruna

2017-02-01

Intra-arterial injection of 131 I Lipiodol is an effective treatment option for primary hepatocellular carcinoma as it delivers high radiation dose to liver tumor tissue with minimal accumulation in adjacent normal tissue. The present article demonstrates design, fabrication, and utilization of a semiautomated radiosynthesis module for preparation of 131 I labeled Lipiodol. The radiolabeling method was standardized for preparation of patient dose of 131 I labeled Lipiodol radiochemical yield (RCY); radiochemical purity (RCP) and pharmaceutical purity of the product were determined using optimized procedures. Sterile and apyrogenic 131 I labeled Lipiodol in >60% RCY could be prepared with >95% RCP. Preclinical evaluation in animals indicated retention of more than 90% of activity at 24 hours postportal vein injection. This is the first report demonstrating potential application of simple user friendly and safe semiautomated system for routine production of 131 I labeled Lipiodol, which is adaptable at centralized hospital radiopharmacies. The described prototype module can be modified as per demand for preparation of other therapeutic radiopharmaceuticals.

A Convenient Route to [68Ga]Ga-MAA for Use as a Particulate PET Perfusion Tracer

PubMed Central

Mathias, Carla J.; Green, Mark A.

2008-01-01

A convenient method is described for compounding [68Ga]Ga-MAA (MAA = macroaggregated human serum albumin) with the eluate of a commercially available TiO2-based 68Ge/68Ga generator. The final [68Ga]Ga-MAA product was obtained with an 81.6 ± 5.3% decay-corrected radiochemical yield and a radiochemical purity of 99.8 ± 0.1% (n = 5). Microscopic examination showed the [68Ga]Ga-MAA product to remain within the original particle size range. The entire procedure, from generator elution to delivery of the final [68Ga]Ga-MAA suspension, could be completed in 25 minutes. Only 4.4 ± 0.9% of the total 68Ge breakthrough remaining associated with the final [68Ga]Ga-MAA product. The procedure allows reasonably convenient preparation of [68Ga]Ga-MAA in a fashion that can be readily adapted to sterile product compounding for human use. PMID:18640845

Synthesis of [{sup 125}I]iodoDPA-713: A new probe for imaging inflammation

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

Wang, Haofan; Pullambhatla, Mrudula; Guilarte, Tomas R.

2009-11-06

[{sup 125}I]IodoDPA-713 [{sup 125}I]1, which targets the translocator protein (TSPO, 18 kDa), was synthesized in seven steps from methyl-4-methoxybenzoate as a tool for quantification of inflammation in preclinical models. Preliminary in vitro autoradiography and in vivo small animal imaging were performed using [{sup 125}I]1 in a neurotoxicant-treated rat and in a murine model of lung inflammation, respectively. The radiochemical yield of [{sup 125}I]1 was 44 {+-} 6% with a specific radioactivity of 51.8 GBq/{mu}mol (1400 mCi/{mu}mol) and >99% radiochemical purity. Preliminary studies showed that [{sup 125}I]1 demonstrated increased specific binding to TSPO in a neurotoxicant-treated rat and increased radiopharmaceutical uptakemore » in the lungs of an experimental inflammation model of lung inflammation. Compound [{sup 125}I]1 is a new, convenient probe for preclinical studies of TSPO activity.« less

Facile radiosynthesis of fluorine-18 labeled beta-blockers. Synthesis, radiolabeling, and ex vivo biodistribution of [18F]-(2S and 2R)-1-(1-fluoropropan-2-ylamino)-3-(m-tolyloxy)propan-2-ol.

PubMed

Stephenson, Karin A; Wilson, Alan A; Meyer, Jeffrey H; Houle, Sylvain; Vasdev, Neil

2008-08-28

An efficient and general method has been developed for fluorine-18 labeling of beta-blockers that possess the propanolamine moiety. A new synthetically versatile intermediate, 3-(1-(benzyloxy)propan-2-yl)-2-oxooxazolidin-5-yl)methyl 4-methylbenzenesulfonate (13), was prepared and can be conjugated to any phenoxy core. To demonstrate the synthetic methodology, fluorinated derivatives of toliprolol were prepared, namely, [(18)F]-(2S and 2R)-1-(1-fluoropropan-2-ylamino)-3-(m-tolyloxy)propan-2-ol ((2S and 2R)-[(18)F]1). The radiosyntheses were accomplished in <1 h, with 20-24% (uncorrected for decay, n = 7) radiochemical yields, >96% radiochemical and >99% enantiomeric purities, with specific activities of 0.9-1.1 Ci/micromol (EOS). Ex vivo biodistribution studies with the radiotracers demonstrated excessively rapid washout that may limit their use for cerebral PET imaging.

Measurement of curium in marine samples

NASA Astrophysics Data System (ADS)

Schneider, D. L.; Livingston, H. D.

1984-06-01

Measurement of environmentally small but detectable amounts of curium requires reliable, accureate, and sensitive analytical methods. The radiochemical separation developed at Woods Hole is briefly reviewed with specific reference to radiochemical interferences in the alpha spectrometric measurement of curium nuclides and to the relative amounts of interferences expected in different oceanic regimes and sample types. Detection limits for 242 Cm and 244 Cm are ultimately limited by their presence in the 243Am used as curium yield monitor. Environmental standard reference materials are evaluated with regard to curium. The marine literature is reviewed and curium measurements are discussed in relation to their source of introduction to the environment. Sources include ocean dumping of low-level radioactive wastes and discharges from nuclear fuel reporcessing activities, In particular, the question of a detectable presence of 244Cm in global fallout from nuclear weapons testing is addressed and shown to be essentially negligible. Analyses of Scottish coastal sedimantes show traces of 242Cm and 244Cm activity which are believed to originate from transport from sources in the Irish Sea.

Novel molecular imaging ligands targeting matrix metalloproteinases 2 and 9 for imaging of unstable atherosclerotic plaques

PubMed Central

Molenaar, Ger; de Waard, Vivian; Lutgens, Esther; van Eck-Smit, Berthe L. F.; de Bruin, Kora; Piek, Jan J.; Eersels, Jos L. H.; Booij, Jan; Verberne, Hein J.; Windhorst, Albert D.

2017-01-01

Molecular imaging of matrix metalloproteinases (MMPs) may allow detection of atherosclerotic lesions vulnerable to rupture. In this study, we develop a novel radiolabelled compound that can target gelatinase MMP subtypes (MMP2/9) with high selectivity and inhibitory potency. Inhibitory potencies of several halogenated analogues of MMP subtype-selective inhibitors (N-benzenesulfonyliminodiacetyl monohydroxamates and N-halophenoxy-benzenesulfonyl iminodiacetyl monohydroxamates) were in the nanomolar range for MMP2/9. The analogue with highest inhibitory potency and selectivity was radiolabelled with [123I], resulting in moderate radiochemical yield, and high radiochemical purity. Biodistribution studies in mice, revealed stabilization in blood 1 hour after intravenous bolus injection. Intravenous infusion of the radioligand and subsequent autoradiography of excised aortas showed tracer uptake in atheroprone mice. Distribution of the radioligand showed co-localization with MMP2/9 immunohistochemical staining. In conclusion, we have developed a novel selective radiolabeled MMP2/9 inhibitor, suitable for single photon emission computed tomography (SPECT) imaging that effectively targets atherosclerotic lesions in mice. PMID:29190653

Evaluation of [(201)Tl](III) Vancomycin in normal rats.

PubMed

Jalilian, Amir Reza; Hosseini, Mohammad Amin; Majdabadi, Abbas; Saddadi, Fariba

2008-01-01

Tl-201 has potential in the preparation of radiolabelled compounds similar to its homologues, like In-111 and radiogallium. In this paper, recently prepared [(201)Tl](III) vancomycin complex ([(201)Tl](III)VAN) has been evaluated for its biological properties. [(201)Tl](III)VAN was prepared according to the optimized conditions followed by biodistribution studies in normal rats for up to 52 h. The Staphylococcus aurous specific binding was checked in vitro. The complex was finally injected to normal rats. Tracer SPECT images were obtained in normal animals and compared to those of (67)Ga-citrate. Freshly-prepared [(201)Tl](III)VAN batches (radiochemical yield > 99%, radiochemical purity > 98%, specific activity approximately 1.2 Ci/mmol) showed a similar biodistribution to that of unlabeled vancomycin. The microorganism binding ratios were 3 and 9 for tracer (201)Tl(3+) and tracer (201)Tl(III)DTPA, respectively, suggesting the preservation of the tracer bioactivity. As a nonspecific cell penetrating tracer, [(201)Tl](III)DTPA was used.

Synthesis of [(11)C]GSK1482160 as a new PET agent for targeting P2X(7) receptor.

PubMed

Gao, Mingzhang; Wang, Min; Green, Mark A; Hutchins, Gary D; Zheng, Qi-Huang

2015-05-01

The authentic standards GSK1482160 and its isomer, as well as the radiolabeling precursors desmethyl-GSK1482160 and Boc-protected desmethyl-GSK1482160 were synthesized from L-pyroglutamic acid, methyl L-pyroglutamate and 2-chloro-3-(trifluoromethyl)benzylamine with overall chemical yield 27-28% in 3 steps, 58% in 4 steps, 76% in 1 step and 33% in 2 steps, respectively. [(11)C]GSK1482160 was prepared from either desmethyl-GSK1482160 or Boc-protected desmethyl-GSK1482160 with [(11)C]CH3OTf through N-[(11)C]methylation and isolated by HPLC combined with SPE in 40-50% and 30-40% radiochemical yield, respectively, based on [(11)C]CO2 and decay corrected to end of bombardment (EOB). The radiochemical purity was >99%, and the specific activity at EOB was 370-1110 GBq/μmol with a total synthesis time of ∼40-min from EOB. Copyright © 2015 Elsevier Ltd. All rights reserved.

Investigation of the possibility of using hydrogranulation in reprocessing radioactive wastes of radiochemical production facilities

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

Revyakin, V.; Borisov, L.M.

1996-05-01

Radio-chemical production facilities are constantly accumulating liquid radioactive wastes (still residues as the result of evaporation of extraction and adsorption solutions etc.) which are a complex multicomponent mixtures. The wastes are frequently stored for extended periods of time while awaiting disposition and in some cases, and this is much worse, they are released into the environment. In this report, I would like to draw your attention to some results we have obtained from investigations aimed at simplifying handing of such wastes by the precipitation of hard to dissolve metal hydroxides, the flocculation of the above into granules with the helpmore » of surface-active agents (in this case a polyacrylamide - PAA), quickly precipitated and easily filtered. The precipitate may be quickly dried and calcinated, if necessary, and transformed into a dense oxide sinter. In other words it may be transformed into a material convenient for storage or burial.« less

Effectiveness of quenchers to reduce radiolysis of (111)In- or (177)Lu-labelled methionine-containing regulatory peptides. Maintaining radiochemical purity as measured by HPLC.

PubMed

de Blois, Erik; Chan, Ho Sze; Konijnenberg, Mark; de Zanger, Rory; Breeman, Wouter A P

2012-01-01

An overview how to measure and to quantify radiolysis by the addition of quenchers and to maintain Radio-Chemical Purity (RCP) of vulnerable methionine-containing regulatory peptides is presented. High RCP was only achieved with a combination of quenchers. However, quantification of RCP is not standardized, and therefore comparison of radiolabelling and RCP of regulatory peptides between different HPLC-systems and between laboratories is cumbersome. Therefore we suggest a set of standardized requirements to quantify RCP by HPLC for radiolabelled DTPA- or DOTA-peptides. Moreover, a dosimetry model was developed to calculate the doses in the reaction vials during radiolabelling and storage of the radiopeptides, and to predict RCP in the presence and absence of quenchers. RCP was measured by HPLC, and a relation between radiation dose and radiolysis of RCP was established. The here described quenchers are tested individually as ƒ(concentration) to investigate efficacy to reduce radiolysis of radiolabelled methionine-containing regulatory peptides.

Radiochemical microassay for aspartate aminotransferase activity in the nervous system

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

Garrison, D.; Beattie, J.; Namboodiri, M.A.

1988-07-01

A radiochemical procedure for measuring aspartate aminotransferase activity in the nervous system is described. The method is based on the exchange of tritium atoms at positions 2 and 3 of L-2,3-(/sup 3/H)aspartate with water when this amino acid is transaminated in the presence of alpha-ketoglutarate to form oxaloacetate. The tritiated water is separated from the radiolabeled aspartate by passing the reaction mixture over a cation exchange column. Confirmation that the radioactivity in the product is associated with water was obtained by separating it by anion exchange HPLC and by evaporation. The product formation is linear with time up to 120more » min and with tissue in the 0.05- to 10-micrograms range. The apparent Km for aspartate in the rat brain homogenate is found to be 0.83 mM and that for alpha-ketoglutarate to be 0.12 mM. Methods that further improve the sensitivity of the assay are also discussed.« less

A prospective study of low fasting glucose with cardiovascular disease events and all-cause mortality: The Women's Health Initiative.

PubMed

Mongraw-Chaffin, Morgana; LaCroix, Andrea Z; Sears, Dorothy D; Garcia, Lorena; Phillips, Lawrence S; Salmoirago-Blotcher, Elena; Zaslavsky, Oleg; Anderson, Cheryl A M

2017-05-01

While there is increasing recognition of the risks associated with hypoglycemia in patients with diabetes, few studies have investigated incident cause-specific cardiovascular outcomes with regard to low fasting glucose in the general population. We hypothesized that low fasting glucose would be associated with cardiovascular disease risk and all-cause mortality in postmenopausal women. To test our hypothesis, we used both continuous incidence rates and Cox proportional hazards models in 17,287 participants from the Women's Health Initiative with fasting glucose measured at baseline. Participants were separated into groups based on fasting glucose level: low (<80mg/dL), normal/reference (80-99mg/dL), impaired (100-125mg/dL), and diabetic (≥126mg/dL). Participants were free of cardiovascular disease at enrollment, had mean age of 62years, and were 52% Caucasian, 24% African American, 8% Asian, and 12% Hispanic. Median follow-up was 15years. Graphs of continuous incidence rates compared to fasting glucose distribution exhibited evidence of a weak J-shaped association with heart failure and mortality that was predominantly due to participants with treated diabetes. Impaired and diabetic fasting glucose were positively associated with all outcomes. Associations for low fasting glucose differed, with coronary heart disease (HR=0.64 (0.42, 0.98)) significantly inverse; stroke (0.73 (0.48, 1.13)), combined cardiovascular disease (0.91 (0.73, 1.14)), and all-cause mortality (0.97 (0.79, 1.20)) null or inverse and not significant; and heart failure (1.27 (0.80, 2.02)) positive and not significant. Fasting glucose at the upper range, but not the lower range, was significantly associated with incident cardiovascular disease and all-cause mortality. Copyright © 2017 Elsevier Inc. All rights reserved.

Glucose excursions and glycaemic control during Ramadan fasting in diabetic patients: insights from continuous glucose monitoring (CGM).

PubMed

Lessan, N; Hannoun, Z; Hasan, H; Barakat, M T

2015-02-01

Ramadan fasting represents a major shift in meal timing and content for practicing Muslims. This study used continuous glucose monitoring (CGM) to assess changes in markers of glycaemic excursions during Ramadan fasting to investigate the short-term safety of this practice in different groups of patients with diabetes. A total of 63 subjects (56 with diabetes, seven healthy volunteers; 39 male, 24 female) had CGM performed during, before and after Ramadan fasting. Mean CGM curves were constructed for each group for these periods that were then used to calculate indicators of glucose control and excursions. Post hoc data analyses included comparisons of different medication categories (metformin/no medication, gliptin, sulphonylurea and insulin). Medication changes during Ramadan followed American Diabetes Association guidelines. Among patients with diabetes, there was a significant difference in mean CGM curve during Ramadan, with a slow fall during fasting hours followed by a rapid rise in glucose level after the sunset meal (iftar). The magnitude of this excursion was greatest in the insulin-treated group, followed by the sulphonylurea-treated group. Markers of control deteriorated in a small number (n=3) of patients. Overall, whether fasting or non-fasting, subjects showed no statistically significant changes in mean interstitial glucose (IG), mean amplitude of glycaemic excursion (MAGE), high and low blood glucose indices (HBGI/LBGI), and number of glucose excursions and rate of hypoglycaemia. The main change in glycaemic control with Ramadan fasting in patients with diabetes is in the pattern of excursions. Ramadan fasting caused neither overall deterioration nor improvement in the majority of patients with good baseline glucose control. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Impact of Ramadan fasting on glucose levels in women with gestational diabetes mellitus treated with diet alone or diet plus metformin: a continuous glucose monitoring study.

PubMed

Afandi, Bachar O; Hassanein, Mohamed M; Majd, Lina M; Nagelkerke, Nico J D

2017-01-01

Women with gestational diabetes mellitus (GDM) are categorized as at high risk for adverse events during Ramadan fasting. However, this is largely based on clinical opinion. In this study, we shed some light on what happens to glucose levels during Ramadan fasting. This is a prospective observational study. A total of 32 patients with GDM were recruited; 10 patients, treated with diet only (group 1), to observe their glucose levels before fasting and 22 patients who insisted on fasting the month of Ramadan, 13 treated with diet only (group 2) and nine treated with diet plus metformin 500 mg twice daily (group 3), to evaluate their glucose levels during fasting. Interstitial glucose was monitored in all by using the iPro2 Professional continuous glucose monitoring (CGM) system. Mean glucose level was 116±21 mg/dL (6.16±1.16 mmol/L), 106±9 mg/dL (5.88±0.49 mmol/L) and 99±7 mg/dL (5.49±0.34 mmol/L) in groups 1, 2 and 3, respectively. Patients in group 1 had the lowest rate of hypoglycemia (50%), followed by patients in group 2 (60%), whereas patients in group 3 had the highest rate of hypoglycemia (78%). CGM data indicates that Ramadan fasting in women with GDM treated with diet alone or with diet plus metformin was associated with lower mean glucose levels and higher rates of hypoglycemia when compared with non-fasting glucose levels. Women with GDM should be advised against fasting during Ramadan until further data is available.

Nuclear Technology Series. Course 20: Radiation Monitoring Techniques (Radiochemical).

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

MRT 5711 - Scope Radiochemical Analysis Comparison: Joint LANL-LLNL FY17 L-2 Milestone

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

Murray, S. D.; Lee, A. S.

A 2016 Level-1 milestone highlighted surprising differences in fundamental data used by the two US design laboratories. To better understand and ultimately resolve those differences, two Level-2 milestones were developed for execution in FY-17 and FY-18.

Optimal quality (131)I-monoclonal antibodies on high-dose labeling in a large reaction volume and temporarily coating the antibody with IODO-GEN.

PubMed

Visser, G W; Klok, R P; Gebbinck, J W; ter Linden, T; van Dongen, G A; Molthoff, C F

2001-03-01

A novel, facile procedure for efficient coupling of high doses of (131)I to monoclonal antibodies (MAbs) was developed with minimal chemical and radiation damage. To diminish the radiation and chemical burden during labeling, iodination was performed in a large reaction volume and by temporarily coating the MAb with a minimal amount of IODO-GEN. The MAb was coated by injection of IODO-GEN (dissolved in acetonitrile [MeCN]) into the aqueous MAb solution, and the coating was subsequently removed by addition of ascorbic acid. For chemoprotection before, during, and after PD-10 purification of the (131)I-MAbs, ascorbic acid and human serum albumin were used. The effects of autoradiolysis in the starting (131)I solution were countered by treatment with NaOH and ascorbic acid. For this so-called IODO-GEN-coated MAb method, the sensitive chimeric MAb MOv18 (c-MOv18) and the more robust murine MAbs K928 and E48 were used. The high-dose (131)I-labeled MAbs were characterized for radiochemical purity and MAb integrity by thin-layer chromatography, high-performance liquid chromatography, and sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by phosphor imager quantification. The high-dose (131)I-labeled MAbs were also characterized for immunoreactivity. The radiopharmacokinetics and biodistribution of (131)I-c-MOv18 were analyzed in human tumor-bearing nude mice. For comparison, (131)I-c-MOv18 batches were made using the conventional chloramine-T or IODO-GEN-coated vial method. Conventional high-dose labeling of 5 mg c-MOv18 with 4.4 GBq (131)I resulted in a labeling yield of 60%, a radiochemical purity of 90%, an immunoreactive fraction of 25% (72% being the maximum in the assay used), and the presence of aggregation and degradation products. Using similar amounts of (131)I and MAb in the IODO-GEN-coated MAb method, 85%-89% overall radiochemical yield, at least 99.7% radiochemical purity, and full preservation of MAb integrity and immunoreactivity were achieved. For this labeling, 5 mg MAb were coated with 35 microg IODO-GEN during 3 min in a reaction volume of 6 mL. Also, biodistribution was optimal, and tumor accumulation was superior to that of coinjected (125)I-c-MOv18 labeled according to the conventional IODO-GEN-coated vial method. A new, facile, high-dose (131)I-labeling method was developed for production of (131)I-labeled MAbs with optimal quality for use in clinical radioimmunotherapy.

Changes in the Arctic: Background and Issues for Congress

DTIC Science & Technology

2013-07-05

continued) within the population more suited to the changed environment) may not be able to occur fast ...natural migration is unlikely to involve the entire suite of species in an ecosystem (e.g., host plants might not move north (or up) as fast as their moth...herbivores, nor as fast as the birds that depend on the moths). Moreover, the southerners will not find a land of sterile bare dirt—the species that

Changes in the Arctic: Background and Issues for Congress

DTIC Science & Technology

2014-02-14

continued) within the population more suited to the changed environment) may not be able to occur fast ...migration is unlikely to involve the entire suite of species in an ecosystem (e.g., host plants might not move north (or up) as fast as their moth...herbivores, nor as fast as the birds that depend on the moths). Moreover, the southerners will not find a land of sterile bare dirt—the species that

Discrete-state representation of ion permeation coupled to fast gating in a model of ClC chloride channels: comparison to multi-ion continuous space Brownian dynamics simulations.

PubMed

Coalson, Rob D; Cheng, Mary Hongying

2010-01-28

A discrete-state model of chloride ion motion in a ClC chloride channel is constructed, following a previously developed multi-ion continuous space model of the same system (Cheng, M. H.; Mamonov, A. B.; Dukes, J. W.; Coalson, R. D. J. Phys. Chem. B 2007, 111, 5956) that included a simplistic representation of the fast gate in this channel. The reducibility of the many-body continuous space to the eight discrete-state model considered in the present work is examined in detail by performing three-dimensional Brownian dynamics simulations of each allowed state-to-state transition in order to extract the appropriate rate constant for this process, and then inserting the pairwise rate constants thereby obtained into an appropriate set of kinetic master equations. Experimental properties of interest, including the rate of Cl(-) ion permeation through the open channel and the average rate of closing of the fast gate as a function of bulk Cl(-) ion concentrations in the intracellular and extracellular electrolyte reservoirs are computed. Good agreement is found between the results obtained via the eight discrete-state model versus the multi-ion continuous space model, thereby encouraging continued development of the discrete-state model to include more complex behaviors observed experimentally in these channels.

EPA Method: Rapid Radiochemical Method for Americium-241, Radium-226, Plutonium-238/-239, Radiostronium, and Isotopic Uranium in Water for Environmental Restoration Following Homeland Security Events

EPA Pesticide Factsheets

SAM lists this method for the qualitative determination of Americium-241, Radium-226, Plutonium-238, Plutonium-239 and isotopic uranium in drinking water samples using alpha spectrometry and radiostrontium using beta counting.

Nature and Analysis of Chemical Species.

ERIC Educational Resources Information Center

Shuman, Mark S.; Fogleman, Wavell W.

1978-01-01

Presents a literature review of the nature and analysis of chemical species in water, covering publications of 1976-77. This review is concerned with inorganics, and it covers: (1) electrochemical analysis; (2) spectroscopy; (3) neutron activation, radiochemical analysis, and isotope dilution. A list of 262 references is also presented. (HM)

Feeding of Rh and Ag isomers in fast-neutron-induced reactions

DOE PAGES

Fotiades, Nikolaos; Devlin, Matthew James; Nelson, Ronald Owen; ...

2016-10-17

In (n,n') reactions on stable Ir and Au isotopes in the mass A=190 region, the experimentally established feeding of the isomers relative to the feeding of the corresponding ground states increases with increasing neutron energy, up to the neutron energy where the (n,2n) reaction channel opens up, and then decreases. In order to check for similar behavior in the mass A=100 region, the feeding of isomers and ground states in fast-neutron-induced reactions on stable isotopes in this mass region was studied. This is of especial interest for Rh which can be used as a radiochemical detector. Here, excited states weremore » studied using the (n,n'γ), (n,2nγ), and (n,3nγ) reactions on 103Rh and 109Ag. A germanium detector array for γ-ray detection and the broad-spectrum pulsed neutron source of the Los Alamos Neutron Science Center's Weapons Neutron Research facility were used for the measurement. The energy of the incident neutrons was determined using the time-of-flight technique. Absolute partial γ-ray cross sections were measured for 57 transitions feeding isomers and ground states in 101,102,103Rh and 107,108,109Ag. The feeding of the isomers was found to be very similar in the corresponding reaction channels and it is compared to the feeding determined for the ground states. In conclusion, the opening of reaction channels at higher neutron energies removes angular momentum from the residual nucleus and reduces the population of the higher-spin isomers relative to the feeding of the lower-spin ground states. Similar behavior was observed in the mass A=190 region in the feeding of higher-spin isomers, but the reverse behavior was observed in 176Lu with a lower-spin isomer and a higher-spin ground state.« less

Feeding of Rh and Ag isomers in fast-neutron-induced reactions

NASA Astrophysics Data System (ADS)

Fotiades, N.; Devlin, M.; Nelson, R. O.; Kawano, T.; Carroll, J. J.

2016-10-01

Background: In (n ,n' ) reactions on stable Ir and Au isotopes in the mass A =190 region, the experimentally established feeding of the isomers relative to the feeding of the corresponding ground states increases with increasing neutron energy, up to the neutron energy where the (n ,2 n ) reaction channel opens up, and then decreases. Purpose: In order to check for similar behavior in the mass A =100 region, the feeding of isomers and ground states in fast-neutron-induced reactions on stable isotopes in this mass region was studied. This is of especial interest for Rh which can be used as a radiochemical detector. Methods: Excited states were studied using the (n ,n'γ ), (n ,2 n γ ), and (n ,3 n γ ) reactions on 103Rh and 109Ag. A germanium detector array for γ -ray detection and the broad-spectrum pulsed neutron source of the Los Alamos Neutron Science Center's Weapons Neutron Research facility were used for the measurement. The energy of the incident neutrons was determined using the time-of-flight technique. Results: Absolute partial γ -ray cross sections were measured for 57 transitions feeding isomers and ground states in 101,102,103Rh and 107,108,109Ag. The feeding of the isomers was found to be very similar in the corresponding reaction channels and it is compared to the feeding determined for the ground states. Conclusions: The opening of reaction channels at higher neutron energies removes angular momentum from the residual nucleus and reduces the population of the higher-spin isomers relative to the feeding of the lower-spin ground states. Similar behavior was observed in the mass A =190 region in the feeding of higher-spin isomers, but the reverse behavior was observed in 176Lu with a lower-spin isomer and a higher-spin ground state.

Feeding of Rh and Ag isomers in fast-neutron-induced reactions

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

Fotiades, Nikolaos; Devlin, Matthew James; Nelson, Ronald Owen

In (n,n') reactions on stable Ir and Au isotopes in the mass A=190 region, the experimentally established feeding of the isomers relative to the feeding of the corresponding ground states increases with increasing neutron energy, up to the neutron energy where the (n,2n) reaction channel opens up, and then decreases. In order to check for similar behavior in the mass A=100 region, the feeding of isomers and ground states in fast-neutron-induced reactions on stable isotopes in this mass region was studied. This is of especial interest for Rh which can be used as a radiochemical detector. Here, excited states weremore » studied using the (n,n'γ), (n,2nγ), and (n,3nγ) reactions on 103Rh and 109Ag. A germanium detector array for γ-ray detection and the broad-spectrum pulsed neutron source of the Los Alamos Neutron Science Center's Weapons Neutron Research facility were used for the measurement. The energy of the incident neutrons was determined using the time-of-flight technique. Absolute partial γ-ray cross sections were measured for 57 transitions feeding isomers and ground states in 101,102,103Rh and 107,108,109Ag. The feeding of the isomers was found to be very similar in the corresponding reaction channels and it is compared to the feeding determined for the ground states. In conclusion, the opening of reaction channels at higher neutron energies removes angular momentum from the residual nucleus and reduces the population of the higher-spin isomers relative to the feeding of the lower-spin ground states. Similar behavior was observed in the mass A=190 region in the feeding of higher-spin isomers, but the reverse behavior was observed in 176Lu with a lower-spin isomer and a higher-spin ground state.« less

Structure of Bordetella pertussis peptidoglycan

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

Folkening, W.J.; Nogami, W.; Martin, S.A.

1987-09-01

Bordetella pertussis Tohama phases I and III were grown to the late-exponential phase in liquid medium containing (/sup 3/H)diaminopimelic acid and treated by a hot (96/sup 0/C) sodium dodecyl sulfate extraction procedure. Washed sodium dodecyl sulfate-insoluble residue from phases I and III consisted of complexes containing protein (ca. 40%) and peptidoglycan (60/sup 6/). Subsequent treatment with proteinase K yielded purified peptidoglycan which contained N-acetylglucosamine, N-acetylmuramic acid, alanine, glutamic acid, and diaminopimelic acid in molar ratios of 1:1:2:1:1 and <2% protein. Radiochemical analyses indicated that /sup 3/H added in diaminopimelic acid was present in peptidoglycan-protein complexes and purified peptidoglycan as diaminopimelicmore » acid exclusively and that pertussis peptidoglycan was not O acetylated, consistent with it being degraded completely by hen egg white lysozyme. Muramidase-derived disaccharide peptide monomers and peptide-cross-linked dimers and higher oligomers were isolated by molecular-sieve chromatography; from the distribution of these peptidoglycan fragments, the extent of peptide cross-linking of both phase I and III peptidoglycan was calculated to be ca. 48%. Unambiguous determination of the structure of muramidase-derived pepidoglycan fragments by fast atom bombardment-mass spectrometry and tandem mass spectrometry indicated that the pertussis peptidoglycan monomer fraction was surprisingly homogeneous, consisting of >95% N-acetylglucosaminyl-N-acetylmuramyl-alanyl-glutamyl-diaminopimelyl-alanine.« less

Automated Synthesis of 68Ga-DOTA-TOC: Methodological Aspects and Suitable Technical Solutions for a Cationic Purification System.

PubMed

Uccelli, Licia; Boschi, Alessandra; Cittanti, Corrado; Martini, Petra; Lodi, Luca; Zappaterra, Elisa; Romani, Simona; Zaccaria, Samanta; Cecconi, Davide; Rambaldi, Ilaria; Santi, Ivan; Panareo, Stefano; Giganti, Melchiore; Bartolomei, Mirco

2018-05-08

The PET Gallium-68 isotope has the advantage of being produced from a generator, so it is also available in nuclear medicine departments without a cyclotron. The preparation of Ga-68 DOTA-labelled compounds is actually performed by remotely controlled automated systems developed in order to assure production efficiency, reproducibility of the results, guarantee fast reaction time, to facilitate the synthesis and minimize the radiation exposure. Many automatic synthesis systems are available on the radiopharmaceutical market, and each of these requires the realization of some technical adaptations for routine use. We reported the Ga-68 DOTATOC production by automated cassette-based theranostic synthesizer system used in combination with a disposable GMP grade cassette system for cationic purification. The synthesizer is integrated with the 68Ge/68Ga generator systems and it allows to perform elution, eluate purification and radiolabeling in about 38 minutes. We have performed between January 2016 and January 2017 over 100 [68Ga]Ga-DOTA-TOC preparation and of these only three have failed. The average synthesis yield of radiopharmaceutical production was 54.4 ± 2.3 % and the average radiochemical purity was 96.94 ± 0.74 %. The methodology and the technical solutions adopted have allowed to obtain a high quality radiopharmaceutical product as required by the European Pharmacopoeia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Gallium-68-labelled NOTA-oligonucleotides: an optimized method for their preparation.

PubMed

Gijs, Marlies; Dammicco, Sylvestre; Warnier, Corentin; Aerts, An; Impens, Nathalie R E N; D'Huyvetter, Matthias; Léonard, Marc; Baatout, Sarah; Luxen, André

2016-02-01

One of the most essential aspects to the success of radiopharmaceuticals is an easy and reliable radiolabelling protocol to obtain pure and stable products. In this study, we optimized the bioconjugation and gallium-68 ((68) Ga) radiolabelling conditions for a single-stranded 40-mer DNA oligonucleotide, in order to obtain highly pure and stable radiolabelled oligonucleotides. Quantitative bioconjugation was obtained for a disulfide-functionalized oligonucleotide conjugated to the macrocylic bifunctional chelator MMA-NOTA (maleimido-mono-amide (1,4,7-triazanonane-1,4,7-triyl)triacetic acid). Next, this NOTA-oligonucleotide bioconjugate was radiolabelled at room temperature with purified and pre-concentrated (68) Ga with quantitative levels of radioactive incorporation and high radiochemical and chemical purity. In addition, high chelate stability was observed in physiological-like conditions (37 °C, PBS and serum), in the presence of a transchelator (EDTA) and transferrin. A specific activity of 51.1 MBq/nmol was reached using a 1470-fold molar excess bioconjugate over (68) Ga. This study presents a fast, straightforward and reliable protocol for the preparation of (68) Ga-radiolabelled DNA oligonucleotides under mild reaction conditions and without the use of organic solvents. The methodology herein developed will be applied to the preparation of oligonucleotidic sequences (aptamers) targeting the human epidermal growth factor receptor 2 (HER2) for cancer imaging. Copyright © 2015 John Wiley & Sons, Ltd.

Positron Emission Tomography Imaging Using Radiolabeled Inorganic Nanomaterials

PubMed Central

Sun, Xiaolian; Cai, Weibo; Chen, Xiaoyuan

2015-01-01

CONSPECTUS Positron emission tomography (PET) is a radionuclide imaging technology that plays an important role in preclinical and clinical research. With administration of a small amount of radiotracer, PET imaging can provide a noninvasive, highly sensitive, and quantitative readout of its organ/tissue targeting efficiency and pharmacokinetics. Various radiotracers have been designed to target specific molecular events. Compared with antibodies, proteins, peptides, and other biologically relevant molecules, nanoparticles represent a new frontier in molecular imaging probe design, enabling the attachment of different imaging modalities, targeting ligands, and therapeutic payloads in a single vector. We introduce the radiolabeled nanoparticle platforms that we and others have developed. Due to the fundamental differences in the various nanoparticles and radioisotopes, most radiolabeling methods are designed case-by-case. We focus on some general rules about selecting appropriate isotopes for given types of nanoparticles, as well as adjusting the labeling strategies according to specific applications. We classified these radiolabeling methods into four categories: (1) complexation reaction of radiometal ions with chelators via coordination chemistry; (2) direct bombardment of nanoparticles via hadronic projectiles; (3) synthesis of nanoparticles using a mixture of radioactive and nonradioactive precursors; (4) chelator-free postsynthetic radiolabeling. Method 1 is generally applicable to different nanomaterials as long as the surface chemistry is well-designed. However, the addition of chelators brings concerns of possible changes to the physicochemical properties of nanomaterials and detachment of the radiometal. Methods 2 and 3 have improved radiochemical stability. The applications are, however, limited by the possible damage to the nanocomponent caused by the proton beams (method 2) and harsh synthetic conditions (method 3). Method 4 is still in its infancy. Although being fast and specific, only a few combinations of isotopes and nanoparticles have been explored. Since the applications of radiolabeled nanoparticles are based on the premise that the radioisotopes are stably attached to the nanomaterials, stability (colloidal and radiochemical) assessment of radiolabeled nanoparticles is also highlighted. Despite the fact that thousands of nanomaterials have been developed for clinical research, only very few have moved to humans. One major reason is the lack of understanding of the biological behavior of nanomaterials. We discuss specific examples of using PET imaging to monitor the in vivo fate of radiolabeled nanoparticles, emphasizing the importance of labeling strategies and caution in interpreting PET data. Design considerations for radiolabeled nanoplatforms for multimodal molecular imaging are also illustrated, with a focus on strategies to combine the strengths of different imaging modalities and to prolong the circulation time. PMID:25635467

29 CFR 1918.26 - Access to barges and river towboats.

Code of Federal Regulations, 2010 CFR

2010-07-01

....26 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Gangways and Other Means of... made fast to the vessel, wharf, or dolphins. ...

Consumption, health attitudes and perception toward fast food among Arab consumers in Kuwait: gender differences.

PubMed

Musaiger, Abdulrahman O

2014-07-15

This study aimed to investigate gender differences in the fast food intake, health attitudes, and perceptions of fast food among adult Arab consumers aged 19 to 65 years in Kuwait. A total of 499 consumers (252 males, 247 females) were selected at convenience from three shopping malls in Kuwait City. The consumers were interviewed using a specially designed questionnaire. The findings revealed that men were more frequently consumed fast food than women (p < 0.001). Men were significantly more likely to consume "double" burgers (52%) than women (29.9%) (P < 0.001). The great majority of consumers (95%) considered fast food harmful to health. However, the consumers were continued to intake fast food (92%), indicating that health information on fast food not necessarly affects their consumption. Local foods were more likely to be considered fast food if eaten as a sandwich or without a disposal container. It can be concluded that fast food perceptions are influenced by gender, media and socio-cultural factors. Nutrition education programmes should focus on nutritive values of the foods rather than on their "fast food" classification.

Estimating Am-241 activity in the body: comparison of direct measurements and radiochemical analyses

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

Lynch, Timothy P.; Tolmachev, Sergei Y.; James, Anthony C.

2009-06-01

The assessment of dose and ultimately the health risk from intakes of radioactive materials begins with estimating the amount actually taken into the body. An accurate estimate provides the basis to best assess the distribution in the body, the resulting dose, and ultimately the health risk. This study continues the time-honored practice of evaluating the accuracy of results obtained using in vivo measurement methods and techniques. Results from the radiochemical analyses of the 241Am activity content of tissues and organs from four donors to the United States Transuranium and Uranium Registries were compared to the results from direct measurements ofmore » radioactive material in the body performed in vivo and post mortem. Two were whole body donations and two were partial body donations The skeleton was the organ with the highest deposition of 241Am activity in all four cases. The activities ranged from 30 Bq to 300 Bq. The skeletal estimates obtained from measurements over the forehead were within 20% of the radiochemistry results in three cases and differed by 78% in one case. The 241Am lung activity estimates ranged from 1 Bq to 30 Bq in the four cases. The results from the direct measurements were within 40% of the radiochemistry results in 3 cases and within a factor of 3 for the other case. The direct measurement estimates of liver activity ranged from 2 Bq to 60 Bq and were generally lower than the radiochemistry results. The results from this study suggest that the measurement methods and calibration techniques used at the In Vivo Radiobioassay and Research Facility to quantify the activity in the lungs, skeleton and liver are reasonable under the most challenging conditions where there is 241Am activity in multiple organs. These methods and techniques are comparable to those used at other Department of Energy sites. This suggests that the current in vivo methods and calibration techniques provide reasonable estimates of radioactive material in the body. Not unexpectedly, there can be significant uncertainty in the estimates especially when activity is also present in other organs.« less

Apparatus for continuous, fast, and precise measurements of position and velocity of a small spherical particle

NASA Technical Reports Server (NTRS)

Venkataraman, T. S.; Eidson, W. W.; Cohen, L. D.; Farina, J. D.; Acquista, C.

1983-01-01

The position and velocity of optically levitated glass spheres (radii 10-20 microns) movng in a gas are measured accurately, rapidly, and continuously using a high-speed rotating polygon mirror. The experimental technique developed here has repeatable position accuracies better than 20 microns. Each measurement takes less than 1 microsec and can be repeated every 100 microsec. The position of the levitated glass spheres can be manipulated accurately by modulating the laser power with an acoustic optic modulator. The technique provides a fast and accurate method to study general particle dynamics in a fluid.

Fast Optical Photometry of V404 Cyg at the MDM Observatory

NASA Astrophysics Data System (ADS)

Terndrup, D.; Wagner, R. M.; Starrfield, S.

2015-06-01

We obtained continuous fast differential optical photometry of V404 Cyg with the 1.3 m McGraw-Hill Telescope of the MDM Observatory on Kitt Peak on the nights of 2015 June 19.220-19.474, 20.194-20.472, 21.199-21.460, and 22.188-22.421 UT.

Fasting induces a biphasic adaptive metabolic response in murine small intestine

PubMed Central

Sokolović, Milka; Wehkamp, Diederik; Sokolović, Aleksandar; Vermeulen, Jacqueline; Gilhuijs-Pederson, Lisa A; van Haaften, Rachel IM; Nikolsky, Yuri; Evelo, Chris TA; van Kampen, Antoine HC; Hakvoort, Theodorus BM; Lamers, Wouter H

2007-01-01

Background The gut is a major energy consumer, but a comprehensive overview of the adaptive response to fasting is lacking. Gene-expression profiling, pathway analysis, and immunohistochemistry were therefore carried out on mouse small intestine after 0, 12, 24, and 72 hours of fasting. Results Intestinal weight declined to 50% of control, but this loss of tissue mass was distributed proportionally among the gut's structural components, so that the microarrays' tissue base remained unaffected. Unsupervised hierarchical clustering of the microarrays revealed that the successive time points separated into distinct branches. Pathway analysis depicted a pronounced, but transient early response that peaked at 12 hours, and a late response that became progressively more pronounced with continued fasting. Early changes in gene expression were compatible with a cellular deficiency in glutamine, and metabolic adaptations directed at glutamine conservation, inhibition of pyruvate oxidation, stimulation of glutamate catabolism via aspartate and phosphoenolpyruvate to lactate, and enhanced fatty-acid oxidation and ketone-body synthesis. In addition, the expression of key genes involved in cell cycling and apoptosis was suppressed. At 24 hours of fasting, many of the early adaptive changes abated. Major changes upon continued fasting implied the production of glucose rather than lactate from carbohydrate backbones, a downregulation of fatty-acid oxidation and a very strong downregulation of the electron-transport chain. Cell cycling and apoptosis remained suppressed. Conclusion The changes in gene expression indicate that the small intestine rapidly looses mass during fasting to generate lactate or glucose and ketone bodies. Meanwhile, intestinal architecture is maintained by downregulation of cell turnover. PMID:17925015

Fasting induces a biphasic adaptive metabolic response in murine small intestine.

PubMed

Sokolović, Milka; Wehkamp, Diederik; Sokolović, Aleksandar; Vermeulen, Jacqueline; Gilhuijs-Pederson, Lisa A; van Haaften, Rachel I M; Nikolsky, Yuri; Evelo, Chris T A; van Kampen, Antoine H C; Hakvoort, Theodorus B M; Lamers, Wouter H

2007-10-09

The gut is a major energy consumer, but a comprehensive overview of the adaptive response to fasting is lacking. Gene-expression profiling, pathway analysis, and immunohistochemistry were therefore carried out on mouse small intestine after 0, 12, 24, and 72 hours of fasting. Intestinal weight declined to 50% of control, but this loss of tissue mass was distributed proportionally among the gut's structural components, so that the microarrays' tissue base remained unaffected. Unsupervised hierarchical clustering of the microarrays revealed that the successive time points separated into distinct branches. Pathway analysis depicted a pronounced, but transient early response that peaked at 12 hours, and a late response that became progressively more pronounced with continued fasting. Early changes in gene expression were compatible with a cellular deficiency in glutamine, and metabolic adaptations directed at glutamine conservation, inhibition of pyruvate oxidation, stimulation of glutamate catabolism via aspartate and phosphoenolpyruvate to lactate, and enhanced fatty-acid oxidation and ketone-body synthesis. In addition, the expression of key genes involved in cell cycling and apoptosis was suppressed. At 24 hours of fasting, many of the early adaptive changes abated. Major changes upon continued fasting implied the production of glucose rather than lactate from carbohydrate backbones, a downregulation of fatty-acid oxidation and a very strong downregulation of the electron-transport chain. Cell cycling and apoptosis remained suppressed. The changes in gene expression indicate that the small intestine rapidly looses mass during fasting to generate lactate or glucose and ketone bodies. Meanwhile, intestinal architecture is maintained by downregulation of cell turnover.

Development and Reliability Testing of a Fast-Food Restaurant Observation Form.

PubMed

Rimkus, Leah; Ohri-Vachaspati, Punam; Powell, Lisa M; Zenk, Shannon N; Quinn, Christopher M; Barker, Dianne C; Pugach, Oksana; Resnick, Elissa A; Chaloupka, Frank J

2015-01-01

To develop a reliable observational data collection instrument to measure characteristics of the fast-food restaurant environment likely to influence consumer behaviors, including product availability, pricing, and promotion. The study used observational data collection. Restaurants were in the Chicago Metropolitan Statistical Area. A total of 131 chain fast-food restaurant outlets were included. Interrater reliability was measured for product availability, pricing, and promotion measures on a fast-food restaurant observational data collection instrument. Analysis was done with Cohen's κ coefficient and proportion of overall agreement for categorical variables and intraclass correlation coefficient (ICC) for continuous variables. Interrater reliability, as measured by average κ coefficient, was .79 for menu characteristics, .84 for kids' menu characteristics, .92 for food availability and sizes, .85 for beverage availability and sizes, .78 for measures on the availability of nutrition information,.75 for characteristics of exterior advertisements, and .62 and .90 for exterior and interior characteristics measures, respectively. For continuous measures, average ICC was .88 for food pricing measures, .83 for beverage prices, and .65 for counts of exterior advertisements. Over 85% of measures demonstrated substantial or almost perfect agreement. Although some measures required revision or protocol clarification, results from this study suggest that the instrument may be used to reliably measure the fast-food restaurant environment.

Relating Memory To Functional Performance In Normal Aging to Dementia Using Hierarchical Bayesian Cognitive Processing Models

PubMed Central

Shankle, William R.; Pooley, James P.; Steyvers, Mark; Hara, Junko; Mangrola, Tushar; Reisberg, Barry; Lee, Michael D.

2012-01-01

Determining how cognition affects functional abilities is important in Alzheimer’s disease and related disorders (ADRD). 280 patients (normal or ADRD) received a total of 1,514 assessments using the Functional Assessment Staging Test (FAST) procedure and the MCI Screen (MCIS). A hierarchical Bayesian cognitive processing (HBCP) model was created by embedding a signal detection theory (SDT) model of the MCIS delayed recognition memory task into a hierarchical Bayesian framework. The SDT model used latent parameters of discriminability (memory process) and response bias (executive function) to predict, simultaneously, recognition memory performance for each patient and each FAST severity group. The observed recognition memory data did not distinguish the six FAST severity stages, but the latent parameters completely separated them. The latent parameters were also used successfully to transform the ordinal FAST measure into a continuous measure reflecting the underlying continuum of functional severity. HBCP models applied to recognition memory data from clinical practice settings accurately translated a latent measure of cognition to a continuous measure of functional severity for both individuals and FAST groups. Such a translation links two levels of brain information processing, and may enable more accurate correlations with other levels, such as those characterized by biomarkers. PMID:22407225

Relating memory to functional performance in normal aging to dementia using hierarchical Bayesian cognitive processing models.

PubMed

Shankle, William R; Pooley, James P; Steyvers, Mark; Hara, Junko; Mangrola, Tushar; Reisberg, Barry; Lee, Michael D

2013-01-01

Determining how cognition affects functional abilities is important in Alzheimer disease and related disorders. A total of 280 patients (normal or Alzheimer disease and related disorders) received a total of 1514 assessments using the functional assessment staging test (FAST) procedure and the MCI Screen. A hierarchical Bayesian cognitive processing model was created by embedding a signal detection theory model of the MCI Screen-delayed recognition memory task into a hierarchical Bayesian framework. The signal detection theory model used latent parameters of discriminability (memory process) and response bias (executive function) to predict, simultaneously, recognition memory performance for each patient and each FAST severity group. The observed recognition memory data did not distinguish the 6 FAST severity stages, but the latent parameters completely separated them. The latent parameters were also used successfully to transform the ordinal FAST measure into a continuous measure reflecting the underlying continuum of functional severity. Hierarchical Bayesian cognitive processing models applied to recognition memory data from clinical practice settings accurately translated a latent measure of cognition into a continuous measure of functional severity for both individuals and FAST groups. Such a translation links 2 levels of brain information processing and may enable more accurate correlations with other levels, such as those characterized by biomarkers.

U.S. EPA response to the Fukushima Daiichi Nuclear Power Plant accident.

PubMed

Tupin, Edward A; Boyd, Michael A; Mosser, Jennifer E; Wieder, Jessica S

2012-05-01

During the spring of 2011, the U.S. Environmental Protection Agency (EPA) used its national radiation monitoring and sampling system, RadNet, to detect, identify, and inform the public about radioactive material in the United States resulting from Japan's Fukushima Daiichi Nuclear Power Plant release. The RadNet system monitors ambient air, drinking water, precipitation, and pasteurized milk for radionuclides. To supplement its existing stationary (fixed) continuous air monitoring system, EPA deployed additional air monitors to Saipan, Guam, and locations in the western United States. The Agency also accelerated the regular quarterly sampling of milk and drinking water and collected an additional round of samples. For two months, staff located at EPA's Headquarters Emergency Operations Center, west coast regional offices, and National Air and Radiation Environmental Lab worked seven days a week to handle the increased radiochemical sample analysis from air filters, precipitation, drinking water, and milk; provide interagency scientific input; and answer press and public inquiries. EPA's data was consistent with what was expected from the Fukushima Daiichi Nuclear Power Plant release. The levels of radioactivity were so low that the readings from the near-real-time RadNet air monitors stayed within normal background ranges. Detailed sample analyses were needed to identify the radionuclides associated with the release. Starting at the end of April and continuing through May 2011, levels of radioactive material decreased as expected.

Radiochemical study of reactions of alkyl cations with amines. I. Reactions of methyl and sec-butyl cations with diethylamine

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

Ignat`ev, I.S.; Kochina, T.A.; Nefedov, V.D.

1995-08-10

Ion-molecular gas-phase reactions of free methyl and sec-butyl cations with diethylamine were studied. These reactions proceed via two competing pathways involving formation of a condensation complex or a proton-transfer complex, the latter process predominating. 32 refs., 1 tab.

Assessment and Control of the Transoceanic Fallout Threat

DTIC Science & Technology

1974-08-01

15 150 Peach 300 30 90 900 Orange 50 5.0 15 150 27 where m is the muscle mass in grams, f. is the fraction of the nuclide that is assimulated (in...Yearly composites are analyzed for eight radionuclides by a gamma scan, and radiochemical analyses are performed to obtain radium and strontium-90

Development of Rapid Radiochemical Method for Gross Alpha and Gross Beta Activity Concentration in Flowback and Produced Waters from Hydraulic Fracturing Operations

EPA Science Inventory

This report summarizes the development and validation of an improved method for the Determination of Gross Alpha and Gross Beta Activity in Flowback and Produced Waters from Hydraulic Fracturing Operations (FPWHFO). Flowback and produced waters are characterized by high concentra...

Method for the melting of metals

DOEpatents

White, Jack C.; Traut, Davis E.

1992-01-01

A method of quantitatively determining the molten pool configuration in melting of metals. The method includes the steps of introducing hafnium metal seeds into a molten metal pool at intervals to form ingots, neutron activating the ingots and determining the hafnium location by radiometric means. Hafnium possesses exactly the proper metallurgical and radiochemical properties for this use.

An Experiment with Manifold Purposes: The Chemical Reactivity of Crystal Defects upon Crystal Dissolution.

ERIC Educational Resources Information Center

Lazzarini, Annaluisa Fantola; Lazzarini, Ennio

1983-01-01

Background information and procedures are provided for an experiment designed to introduce (1) crystal defects and their reactivity upon crystal dissolution; (2) hydrates electron and its reactivity; (3) application of radiochemical method of analysis; and (4) the technique of competitive kinetics. Suggested readings and additional experiments are…

RADIOACTIVE WASTE PROCESSING AND DISPOSAL: A BIBLIOGRAPHY OF SELECTED REPORT LITERATURE

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

Voress, H.E.; Davis, T.F.; Hubbard, T.N. Jr.

1958-06-01

An annotated bibliography is presented containing 698 references to unclassifled reports on currert and proposed ranioactive waste processing and disposal practices for solutions from radiochemical processing plants and laboratories, decontamination of surfaces, air cleaning, and other related subjects. Author, corporate author, subject, and report nuunber indexes are included. (auth)

High Yield Production and Radiochemical Isolation of Isotopically Pure Arsenic-72 and Novel Radioarsenic Labeling Strategies for the Development of Theranostic Radiopharmaceuticals.

PubMed

Ellison, Paul A; Barnhart, Todd E; Chen, Feng; Hong, Hao; Zhang, Yin; Theuer, Charles P; Cai, Weibo; Nickles, Robert J; DeJesus, Onofre T

2016-01-20

Radioisotopes of arsenic are of considerable interest to the field of nuclear medicine with unique nuclear and chemical properties making them well-suited for use in novel theranostic radiopharmaceuticals. However, progress must still be made in the production of isotopically pure radioarsenic and in its stable conjugation to biological targeting vectors. This work presents the production and irradiation of isotopically enriched (72)Ge(m) discs in an irrigation-cooled target system allowing for the production of isotopically pure (72)As with capability on the order of 10 GBq. A radiochemical separation procedure isolated the reactive trivalent radioarsenic in a small volume buffered aqueous solution, while reclaiming (72)Ge target material. The direct thiol-labeling of a monoclonal antibody resulted in a conjugate exhibiting exceptionally poor in vivo stability in a mouse model. This prompted further investigations to alternative radioarsenic labeling strategies, including the labeling of the dithiol-containing chelator dihydrolipoic acid, and thiol-modified mesoporous silica nanoparticles (MSN-SH). Radioarsenic-labeled MSN-SH showed exceptional in vivo stability toward dearsenylation.

High Yield Production and Radiochemical Isolation of Isotopically Pure Arsenic-72 and Novel Radioarsenic Labeling Strategies for the Development of Theranostic Radiopharmaceuticals

PubMed Central

Ellison, Paul A.; Barnhart, Todd E.; Chen, Feng; Hong, Hao; Zhang, Yin; Theuer, Charles P.; Cai, Weibo; Nickles, Robert J.; DeJesus, Onofre T.

2016-01-01

Radioisotopes of arsenic are of considerable interest to the field of nuclear medicine with unique nuclear and chemical properties making them well-suited for use in novel theranostic radiopharmaceuticals. However, progress must still be made in the production of isotopically pure radioarsenic and in its stable conjugation to biological targeting vectors. This work presents the production and irradiation of isotopically enriched 72Ge(m) discs in an irrigation-cooled target system allowing for the production of isotopically pure 72As with capability on the order of 10 GBq. A radiochemical separation procedure isolated the reactive trivalent radioarsenic in a small volume buffered aqueous solution, while reclaiming 72Ge target material. The direct thiol-labeling of a monoclonal antibody resulted in a conjugate exhibiting exceptionally poor in vivo stability in a mouse model. This prompted further investigations to alternative radioarsenic labeling strategies, including the labeling of the dithiol-containing chelator dihydrolipoic acid, and thiol-modified mesoporous silica nanoparticles (MSN-SH). Radioarsenic-labeled MSN-SH showed exceptional in vivo stability toward dearsenylation. PMID:26646989

Behavior of radioactive iodine and technetium in the spray calcination of high-level waste

NASA Astrophysics Data System (ADS)

Knox, C. A.; Farnsworth, R. K.

1981-08-01

The Remote Laboratory-Scale Waste Treatment Facility (RLSWTF) was designed and built as a part of the High-Level Waste Immobilization Program (now the High-Level Waste Process Development Program) at the Pacific Northwest Laboratory. In facility, installed in a radiochemical cell, is described in which installed in a radiochemical cell is described in which small volumes of radioactive liquid wastes can be solidified, the process off gas can be analyzed, and the methods for decontaminating this off gas can be tested. During the spray calcination of commercial high-level liquid waste spiked with Tc-99 and I-131 and 31 wt% loss of I-131 past the sintered-metal filters. These filters and venturi scrubber were very efficient in removing particulates and Tc-99 from the the off-gas stream. Liquid scrubbers were not efficient in removing I-131 as 25% of the total lost went to the building off-gas system. Therefore, solid adsorbents are needed to remove iodine. For all future operations where iodine is present, a silver zeolite adsorber is to be used.

Final Report 2007: DOE-FG02-87ER60561

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

Kilbourn, Michael R

2007-04-26

This project involved a multi-faceted approach to the improvement of techniques used in Positron Emission Tomography (PET), from radiochemistry to image processing and data analysis. New methods for radiochemical syntheses were examined, new radiochemicals prepared for evaluation and eventual use in human PET studies, and new pre-clinical methods examined for validation of biochemical parameters in animal studies. The value of small animal PET imaging in measuring small changes of in vivo biochemistry was examined and directly compared to traditional tissue sampling techniques. In human imaging studies, the ability to perform single experimental sessions utilizing two overlapping injections of radiopharmaceuticals wasmore » tested, and it was shown that valid biochemical measures for both radiotracers can be obtained through careful pharmacokinetic modeling of the PET emission data. Finally, improvements in reconstruction algorithms for PET data from small animal PET scanners was realized and these have been implemented in commercial releases. Together, the project represented an integrated effort to improve and extend all basic science aspects of PET imaging at both the animal and human level.« less

Development of a beta-spectrometer using PIPS technology

PubMed

Courti; Goutelard; Burger; Blotin

2000-07-01

Various anthropogenic sources contribute to the inventory of long live beta-emitters in the environment. Studies have been carried out to obtain the 90Sr distribution in environment in order to estimate its impact in terms of radiation exposure to humans. The Laboratory routinely measures 90Sr by proportional counter after radiochemistry. An incomplete radiochemical separation leads to a deposit submitted to count polluted by natural beta-emitters. In order to confirm the result, 90Y (daughter of 90Sr), is extracted from the final radiochemical fraction and counted. The 90Y decreasing (T(1/2) = 2.67 days) is checked by successive counts over 64 h. The delay between the end of radiochemistry and the counting is imposed by 15 days to allow radioactive equilibrium between 90Sr and 90Y to be established. In order to remove this delay the purity of the 90Sr fraction source can be verified by beta-spectrometry. Thus, a beta-spectrometer is under development in collaboration with Canberra Semi-Conductor and Canberra Electronic. It consists in a PIPS detector where several silicon layers are combined. Initial results will be presented in this paper.

Novel synthesis and initial preclinical evaluation of (18)F-[FDG] labeled rhodamine: a potential PET myocardial perfusion imaging agent.

PubMed

AlJammaz, Ibrahim; Al-Otaibi, Basim; AlHindas, Hussein; Okarvi, Subhani M

2015-10-01

Myocardial perfusion imaging is one of the most commonly performed investigations in nuclear medicine studies. Due to the clinical importance of [(18)F]-fluoro-2-deoxy-D-glucose ([(18)F]-FDG) and its availability in almost every PET center, a new radiofluorinated [(18)F]-FDG-rhodamine conjugate was synthesized using [(18)F]-FDG as a prosthetic group. In a convenient and simple one-step radiosynthesis, [(18)F]-FDG-rhodamine conjugate was prepared in quantitative radiochemical yields, with total synthesis time of nearly 20 min and radiochemical purity of greater than 98%, without the need for HPLC purification, which make these approaches amenable for automation. Biodistribution studies in normal rats at 60 min post-injection demonstrated a high uptake in the heart (>11% ID/g) and favorable pharmacokinetics. Additionally, [(18)F]-FDG-rhodamine showed an extraction value of 27.63%±5.12% in rat hearts. These results demonstrate that [(18)F]-FDG-rhodamine conjugate may be useful as an imaging agent for the positron emission tomography evaluation of myocardial perfusion. Copyright © 2015 Elsevier Inc. All rights reserved.

Progress on the chemical separation of fission fragments from 236Np produced by proton irradiation of natural uranium target

NASA Astrophysics Data System (ADS)

Larijani, C.; Jerome, S. M.; Lorusso, G.; Ivanov, P.; Russell, B.; Pearce, A. K.; Regan, P. H.

2017-11-01

The aim of the current work is to develop and validate a radiochemical separation scheme capable of separating both 236gNp and 236Pu from a uranium target of natural isotopic composition ( 1 g uranium) and 200 MBq of fission decay products. A target containing 1.2 g of UO2 was irradiated with a beam of 25 MeV protons with a typical beam current of 30 μA for 19 h in December 2013 at the University of Birmingham Cyclotron facility. Using literature values for the production cross-section for fusion of protons with uranium targets, we estimate that an upper limit of approximately 250 Bq of activity from the 236Np ground state was produced in this experiment. Using a radiochemical separation scheme, Np and Pu fractions were separated from the produced fission decay products, with analyses of the target-based final reaction products made using Inductively Couple Plasma Mass Spectrometry (ICP-MS) and high-resolution α particle and γ-ray spectrometry.

Clearance of polonium-210-enriched cigarette smoke from the rat trachea and lung

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

Cohen, B.S.; Harley, N.H.; Tso, T.C.

The distribution and clearance of alpha radioactivity in the lungs of rats were measured after inhalation of smoke from cigarettes highly enriched in /sup 210/Po. Female Fischer rats were exposed daily for 6 months to smoke from cigarettes with 500 times the normal content of /sup 210/Po. Control rats were exposed to standard cigarette smoke. Animals were serially withdrawn and killed. After necropsy the trachea, major bronchi, larynx, and nasopharynx were examined for surface alpha activity by an etched track technique utilizing cellulose nitrate detectors. Areas of accumulated activity were seen on samples of larynx from rats exposed to themore » /sup 210/Po-enriched cigarettes. No other local accumulations were seen on the airways. The lower lungs were analyzed radiochemically for /sup 210/Po. Both radiochemical analysis and track measurements showed highly elevated activity concentrations in rats exposed to the /sup 210/Po-enriched cigarettes. Following withdrawal from smoking, both short- and long-term clearance components were seen. The parameters which fit the postexposure data for clearance of the lung burden cannot fit the buildup during the exposure period.« less

Clearance of polonium-210-enriched cigarette smoke from the rat trachea and lung.

PubMed

Cohen, B S; Harley, N H; Tso, T C

1985-06-30

The distribution and clearance of alpha radioactivity in the lungs of rats were measured after inhalation of smoke from cigarettes highly enriched in 210Po. Female Fischer rats were exposed daily for 6 months to smoke from cigarettes with 500 times the normal content of 210Po. Control rats were exposed to standard cigarette smoke. Animals were serially withdrawn and killed. After necropsy the trachea, major bronchi, larynx, and nasopharynx were examined for surface alpha activity by an etched track technique utilizing cellulose nitrate detectors. Areas of accumulated activity were seen on samples of larynx from rats exposed to the 210Po-enriched cigarettes. No other local accumulations were seen on the airways. The lower lungs were analyzed radiochemically for 210Po. Both radiochemical analysis and track measurements showed highly elevated activity concentrations in rats exposed to the 210Po-enriched cigarettes. Following withdrawal from smoking, both short- and long-term clearance components were seen. The parameters which fit the postexposure data for clearance of the lung burden cannot fit the buildup during the exposure period.

Fully automated synthesis of [(18) F]fluoro-dihydrotestosterone ([(18) F]FDHT) using the FlexLab module.

PubMed

Ackermann, Uwe; Lewis, Jason S; Young, Kenneth; Morris, Michael J; Weickhardt, Andrew; Davis, Ian D; Scott, Andrew M

2016-08-01

Imaging of androgen receptor expression in prostate cancer using F-18 FDHT is becoming increasingly popular. With the radiolabelling precursor now commercially available, developing a fully automated synthesis of [(18) F] FDHT is important. We have fully automated the synthesis of F-18 FDHT using the iPhase FlexLab module using only commercially available components. Total synthesis time was 90 min, radiochemical yields were 25-33% (n = 11). Radiochemical purity of the final formulation was > 99% and specific activity was > 18.5 GBq/µmol for all batches. This method can be up-scaled as desired, thus making it possible to study multiple patients in a day. Furthermore, our procedure uses 4 mg of precursor only and is therefore cost-effective. The synthesis has now been validated at Austin Health and is currently used for [(18) F]FDHT studies in patients. We believe that this method can easily adapted by other modules to further widen the availability of [(18) F]FDHT. Copyright © 2016 John Wiley & Sons, Ltd.

A potent IκB kinase-β inhibitor labeled with carbon-14 and deuterium.

PubMed

Latli, Bachir; Eriksson, Magnus; Hrapchak, Matt; Busacca, Carl A; Senanayake, Chris H

2016-06-30

3-Amino-4-(1,1-difluoro-propyl)-6-(4-methanesulfonyl-piperidin-1-yl)-thieno[2,3-b]pyridine-2-carboxylic acid amide (1) is a potent IκB Kinase-β (IKK-β) inhibitor. The efficient preparations of this compound labeled with carbon-14 and deuterium are described. The carbon-14 synthesis was accomplished in six radiochemical steps in 25% overall yield. The key transformations were the modified Guareschi-Thorpe condensation of 2-cyano-(14) C-acetamide and a keto-ester followed by chlorination to 2,6-dichloropyridine derivative in one pot. The isolated dichloropyridine was then converted in three steps in one pot to [(14) C]-(1). The carbon-14 labeled (1) was isolated with a specific activity of 54.3 mCi/mmol and radiochemical purity of 99.8%. The deuterium labeled (1) was obtained in eight steps and in 57% overall chemical yield using 4-hydroxypiperidine-2,2,3,3,4,5,5,6,6-(2) H9 . The final three steps of this synthesis were run in one pot. Copyright © 2016 John Wiley & Sons, Ltd.

Carbon-14 radiolabeling and tissue distribution evaluation of MMV390048.

PubMed

Sonopo, Molahlehi S; Pillay, Adushan; Chibale, Kelly; Marjanovic-Painter, Biljana; Donini, Cristina; Zeevaart, Jan R

2016-12-01

The antimalarial compound MMV390048 ([ 14 C]-11) was labeled with carbon-14 isotope via a 3-step synthesis. It was obtained in a 15.5% radiochemical overall yield from carbon-14 labeled methyl iodide with a radiochemical purity of >99%. After single oral administration of [ 14 C]-11 to albino and pigmented rats its tissue distribution profile was studied. Tissue distribution results showed high local exposure in the GI tract and excretory organs but low exposure of all other tissues. The radioactivity uptake was higher in the eyes of the pigmented rats than in the eyes of the albino rats at all-time points. The highest accumulation reached in the eyes of the pigmented rats was 0.46% at 6 hours. However, these levels are still very low as compared to the other organs studied. There was very little radioactivity from MMV390048 ([ 14 C]-11) present in the skin of both the albino and pigmented rats. The results obtained are supportive of further development of MMV390048 as a potential antimalarial compound. Copyright © 2016 John Wiley & Sons, Ltd.

Synthesis and analysis of 2-[211At]-L-phenylalanine and 4-[211At]-L-phenylalanine and their uptake in human glioma cell cultures in-vitro.

PubMed

Meyer, Geerd J; Walte, Almut; Sriyapureddy, Siva R; Grote, Michaela; Krull, Doris; Korkmaz, Zekiye; Knapp, Wolfram H

2010-06-01

2-[211At]-L-phenylalanine and 4-[211At]-L-phenylalanine were prepared from the corresponding iodo and bromo derivatives using the Cu(+)-assisted nucleophilic exchange. 4-[211At]-L-phenylalanine was additionally prepared by destannylation of the BOC-derivatized 4-tributylstannyl-L-phenylalanine. Radiochemical yields of 2-[211At]-L-phenylalanine and 4-[211At]-L-phenylalanine by nucleophilic exchange were 52-74% and 65-85%. Radiochemical yield of 4-[211At]-L-phenylalanine by electrophilic destannylation was 35-50%. HPLC sequence analysis showed that 2-[211At]-L-phenylalanine followed the halogen sequence (F

Design of CGMP Production of 18F- and 68Ga-Radiopharmaceuticals

PubMed Central

Chu, Pei-Chun; Chao, Hao-Yu; Shieh, Wei-Chen; Chen, Chuck C.

2014-01-01

Objective. Radiopharmaceutical production process must adhere to current good manufacturing process (CGMP) compliance to ensure the quality of precursor, prodrug (active pharmaceutical ingredient, API), and the final drug product that meet acceptance criteria. We aimed to develop an automated system for production of CGMP grade of PET radiopharmaceuticals. Methods. The hardware and software of the automated synthesizer that fit in the hot cell under cGMP requirement were developed. Examples of production yield and purity for 68Ga-DOTATATE and 18F-FDG at CGMP facility were optimized. Analytical assays and acceptance criteria for cGMP grade of 68Ga-DOTATATE and 18F-FDG were established. Results. CGMP facility for the production of PET radiopharmaceuticals has been established. Radio-TLC and HPLC analyses of 68Ga-DOTATATE and 18F-FDG showed that the radiochemical purity was 92% and 96%, respectively. The products were sterile and pyrogenic-free. Conclusion. CGMP compliance of radiopharmaceuticals has been reviewed. 68Ga-DOTATATE and 18F-FDG were synthesized with high radiochemical yield under CGMP process. PMID:25276810

Lifetime testing UV LEDs for use in the LISA charge management system

NASA Astrophysics Data System (ADS)

Hollington, D.; Baird, J. T.; Sumner, T. J.; Wass, P. J.

2017-10-01

As a future charge management light source, UV light-emitting diodes (UV LEDs) offer far superior performance in a range of metrics compared to the mercury lamps used in the past. As part of a qualification program a number of short wavelength UV LEDs have been subjected to a series of lifetime tests for potential use on the laser interferometer space antenna (LISA) mission. These tests were performed at realistic output levels for both fast and continuous discharging in either a DC or pulsed mode of operation and included a DC fast discharge test spanning 50 days, a temperature dependent pulsed fast discharge test spanning 21 days and a pulsed continuous discharge test spanning 507 days. Two types of UV LED have demonstrated lifetimes equivalent to over 25 years of realistic mission usage with one type providing a baseline for LISA and the other offering a backup solution.

Numerical simulations of electrohydrodynamic evolution of thin polymer films

NASA Astrophysics Data System (ADS)

Borglum, Joshua Christopher

Recently developed needleless electrospinning and electrolithography are two successful techniques that have been utilized extensively for low-cost, scalable, and continuous nano-fabrication. Rational understanding of the electrohydrodynamic principles underneath these nano-manufacturing methods is crucial to fabrication of continuous nanofibers and patterned thin films. This research project is to formulate robust, high-efficiency finite-difference Fourier spectral methods to simulate the electrohydrodynamic evolution of thin polymer films. Two thin-film models were considered and refined. The first was based on reduced lubrication theory; the second further took into account the effect of solvent drying and dewetting of the substrate. Fast Fourier Transform (FFT) based spectral method was integrated into the finite-difference algorithms for fast, accurately solving the governing nonlinear partial differential equations. The present methods have been used to examine the dependencies of the evolving surface features of the thin films upon the model parameters. The present study can be used for fast, controllable nanofabrication.

6-DoF Haptic Rendering Using Continuous Collision Detection between Points and Signed Distance Fields.

PubMed

Hongyi Xu; Barbic, Jernej

2017-01-01

We present an algorithm for fast continuous collision detection between points and signed distance fields, and demonstrate how to robustly use it for 6-DoF haptic rendering of contact between objects with complex geometry. Continuous collision detection is often needed in computer animation, haptics, and virtual reality applications, but has so far only been investigated for polygon (triangular) geometry representations. We demonstrate how to robustly and continuously detect intersections between points and level sets of the signed distance field. We suggest using an octree subdivision of the distance field for fast traversal of distance field cells. We also give a method to resolve continuous collisions between point clouds organized into a tree hierarchy and a signed distance field, enabling rendering of contact between rigid objects with complex geometry. We investigate and compare two 6-DoF haptic rendering methods now applicable to point-versus-distance field contact for the first time: continuous integration of penalty forces, and a constraint-based method. An experimental comparison to discrete collision detection demonstrates that the continuous method is more robust and can correctly resolve collisions even under high velocities and during complex contact.

Short periods of fasting followed by refeeding change the expression of muscle growth-related genes in juvenile Nile tilapia (Oreochromis niloticus).

PubMed

Nebo, Caroline; Portella, Maria Célia; Carani, Fernanda Regina; de Almeida, Fernanda Losi Alves; Padovani, Carlos Roberto; Carvalho, Robson Francisco; Dal-Pai-Silva, Maeli

2013-04-01

Muscle growth mechanisms are controlled by molecular pathways that can be affected by fasting and refeeding. In this study, we hypothesized that short period of fasting followed by refeeding would change the expression of muscle growth-related genes in juvenile Nile tilapia (Oreochromis niloticus). The aim of this study was to analyze the expression of MyoD, myogenin and myostatin and the muscle growth characteristics in the white muscle of juvenile Nile tilapia during short period of fasting followed by refeeding. Juvenile fish were divided into three groups: (FC) control, feeding continuously for 42 days, (F5) 5 days of fasting and 37 days of refeeding, and (F10) 10 days of fasting and 32 days of refeeding. At days 5 (D5), 10 (D10), 20 (D20) and 42 (D42), fish (n=14 per group) were anesthetized and euthanized for morphological, morphometric and gene expression analyses. During the refeeding, fasted fish gained weight continuously and, at the end of the experiment (D42), F5 showed total compensatory mass gain. After 5 and 10 days of fasting, a significant increase in the muscle fiber frequency (class 20) occurred in F5 and F10 compared to FC that showed a high muscle fiber frequency in class 40. At D42, the muscle fiber frequency in class 20 was higher in F5. After 5 days of fasting, MyoD and myogenin gene expressions were lower and myostatin expression levels were higher in F5 and F10 compared to FC; at D42, MyoD, myogenin and myostatin gene expression was similar among all groups. In conclusion, this study showed that short periods of fasting promoted muscle fiber atrophy in the juvenile Nile tilapia and the refeeding caused compensatory mass gain and changed the expression of muscle growth-related genes that promote muscle growth. These fasting and refeeding protocols have proven useful for understanding the effects of alternative warm fish feeding strategies on muscle growth-related genes. Copyright © 2013. Published by Elsevier Inc.

Complementary rare earth element patterns in unique achondrites, such as ALHA 77005 and shergottites, and in the earth

NASA Technical Reports Server (NTRS)

Ma, M.-S.; Schmitt, R. A.; Laul, J. C.

1982-01-01

Abundances of major, minor, and trace elements are determined in the Antarctic achondrite Allan Hills (ALHA) 77005 via sequential instrumental and radiochemical neutron activation analysis. The rare earth element (REE) abundances of ALHA 77005 reveal a unique chondritic normalized pattern; that is, the REEs are nearly unfractionated from La to Pr at approximately 1.0X chondrites, monotonically increased from Pr to Gd at approximately 3.4X with no Eu anomaly, nearly unfractionated from Gd and Ho and monotonically decreased from Ho to Lu at approximately 2.2X. It is noted that this unique REE pattern of ALHA 77005 can be modeled by a melting process involving a continuous melting and progressive partial removal of melt from a light REE enriched source material. In a model of this type, ALHA 77005 could represent either a crystallized cumulate from such a melt or the residual source material. Calculations show that the parent liquids for the shergottites could also be derived from a light REE enriched source material similar to that for ALHA 77005.

Electron beam irradiation of fluoropolymers containing polyethers

NASA Astrophysics Data System (ADS)

Bucio, E.; Burillo, G.; Tapia, F.; Adem, E.; Cedillo, G.; Cassidy, P. E.

2009-02-01

A highly fluorinated monomer, 1,3-bis(1,1,1,3,3,3-hexafluoro-2-pentafluorophenyl methoxy-2-propyl)benzene (12F-FBE) was polymerized with some diphenols by polycondensation and then was electron beam irradiated between 100 and 1000 kGy to determine degradation radiochemistry yield ( Gs) by gel permeation chromatography (GPC). The samples were characterized after irradiation by DSC, FTIR, and nuclear magnetic resonance (NMR). The fluoropolymers show apparent degradation in mechanical properties at 300 kGy, except 12F-FBE polymerized with biphenol and bisphenol A, when they did not show any apparent physical change up to 300 kGy; and continue to be flexible and transparent, with a radiochemical yield scission ( Gs) of 0.75, 0.53, 0.88, and 0.38 for 12F-FBE/SDL aliphatic, 12F-FBE/biphenol, 12F-FBE/bisphenol A, and 12F-FBE/bisphenol O, respectively. The number average molecular weights for three of the polymers decrease upon 1000 kGy irradiation to 10% of their original values; however, the polymer from bisphenol A is much more stable and its Mn decreases to only 24% of original.

Validation of the FAST skating protocol to predict aerobic power in ice hockey players.

PubMed

Petrella, Nicholas J; Montelpare, William J; Nystrom, Murray; Plyley, Michael; Faught, Brent E

2007-08-01

Few studies have reported a sport-specific protocol to measure the aerobic power of ice hockey players using a predictive process. The purpose of our study was to validate an ice hockey aerobic field test on players of varying ages, abilities, and levels. The Faught Aerobic Skating Test (FAST) uses an on-ice continuous skating protocol on a course measuring 160 feet (48.8 m) using a CD to pace the skater with a beep signal to cross the starting line at each end of the course. The FAST incorporates the principle of increasing workload at measured time intervals during a continuous skating exercise. Step-wise multiple regression modelling was used to determine the estimate of aerobic power. Participants completed a maximal aerobic power test using a modified Bruce incremental treadmill protocol, as well as the on-ice FAST. Normative data were collected on 406 ice hockey players (291 males, 115 females) ranging in age from 9 to 25 y. A regression to predict maximum aerobic power was developed using body mass (kg), height (m), age (y), and maximum completed lengths of the FAST as the significant predictors of skating aerobic power (adjusted R2 = 0.387, SEE = 7.25 mL.kg-1.min-1, p < 0.0001). These results support the application of the FAST in estimating aerobic power among male and female competitive ice hockey players between the ages of 9 and 25 years.

Incorporation of organic tritium (3H) by marine organisms and sediment in the severn estuary/Bristol channel (UK).

PubMed

McCubbin, D; Leonard, K S; Bailey, T A; Williams, J; Tossell, P

2001-10-01

Discharges of tritium (3H) into the Severn estuary/Bristol Channel (UK) arise from the authorized release of wastes from nuclear power plants at Hinkley Point and Berkley/Oldbury and from the Nycomed-Amersham radiochemical plant, via the sewer system, at Cardiff. The wastes from the nuclear power plants probably consist almost entirely of 3H2O, whereas those from the radiochemical plant also include uncharacterized 3H labelled organic compounds. The total 3H concentrations in demersal fish and other benthic organisms in the vicinity of the Cardiff Eastern sewer outfall are significantly elevated compared to those observed around other UK nuclear establishments. Concentrations in filtered seawater were approximately 10 Bq kg(-1) whilst levels in surface sediment, seaweed (Fucus vesiculosis) and mussels (Mytilus edulis)/flounder (Platichthys flesus) were in the order of 6 x 10(2), 2 x 10(3), and 10(5) Bq kg(-1) (dry weight), respectively. Almost all the 3H found in sediment and biota were organically bound tritium (OBT). The high concentration in these materials, relative to that in seawater, is due to the presence of bioavailable organic 3H labelled compounds in the radiochemical waste. It is suggested that bioaccumulation of 3H by benthic organisms and demersal fish occurs primarily via a pathway of physico-chemical sorption/bacterial transformation of dissolved 3H labelled organic compounds into particulate organic matter, and subsequent transfer up a web of sediment dwelling microbes and meiofauna. Variations in 3H accumulation between individual organisms have been interpreted in terms of their different feeding behaviour. Relatively low concentrations were observed in the herbivorous winkle (Littorina littorea) and the pelagic Sprat (Spratus spratus) compared with other benthic organisms and demersal fish. The elevated 3H concentrations in seafood, due to bioaccumulation of OBT, have low radiological significance even for the local critical group of seafood consumers.

Periodic Verification of the Scaling Factor for Radwastes in Korean NPPs - 13294

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

Park, Yong Joon; Ahn, Hong Joo; Song, Byoung Chul

2013-07-01

According to the acceptance criteria for a low and intermediate level radioactive waste (LILW) listed in Notice No. 2012-53 of the Nuclear Safety and Security Commission (NSSC), specific concentrations of radionuclides inside a drum has to be identified and quantified. In 5 years of effort, scaling factors were derived through destructive radiochemical analysis, and the dry active waste, spent resin, concentration bottom, spent filter, and sludge drums generated during 2004 ∼ 2008 were evaluated to identify radionuclide inventories. Eventually, only dry active waste among LILWs generated from Korean NPPs were first shipped to a permanent disposal facility on December 2010.more » For the LILWs generated after 2009, the radionuclides are being radiochemically quantified because the Notice clarifies that the certifications of the scaling factors should be verified biennially. During the operation of NPP, the radionuclides designated in the Notice are formed by neutron activation of primary coolant, reactor structural materials, corrosion products, and fission products released into primary coolant through defects or failures in fuel cladding. Eventually, since the radionuclides released into primary coolant are transported into the numerous auxiliary and support systems connected to primary system, the LILWs can be contaminated, and the radionuclides can have various concentration distributions. Thus, radioactive wastes, such as spent resin and dry active waste generated at various Korean NPP sites, were sampled at each site, and the activities of the regulated radionuclides present in the sample were determined using radiochemical methods. The scaling factors were driven on the basis of the activity ratios between a or β-emitting nuclides and γ-emitting nuclides. The resulting concentrations were directly compared with the established scaling factors' data using statistical methods. In conclusions, the established scaling factors were verified with a reliability of within 2σ, and the scaling factors will be applied for newly analyzed LILWs to evaluate the radionuclide inventories. (authors)« less

Imaging of neuroendocrine tumors in 300 patients following injection of I-123 mIBG or 1-131 mIBG prepared from a {open_quotes}cold kit{close_quotes}

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

Karesh, S.M.; Henkin, R.E.

1994-05-01

During the past 6 years, we have performed approximately 300 scans for neuroendocrine tumors in an extremely varied patient base, with 65% of patients receiving I-123 mIBG and 35%, I-131 mIBG. Imaging was performed at 24-72 hr, depending upon the isotope used. The most common clinical indication was for pheochromocytoma (>90%), followed by neuroblastoma, paraganglioma, medullary carcinoma of the thyroid, and carcinoid tumors. Radiolabeling was performed by a modification of Mock`s procedure. The radioiodide was added to a very stable {open_quotes}cold kit{close_quotes} developed in-house. The kit contains 1 ml of water for injection, 2 mg of mIBG hemisulfate, and 12more » mg of ammonium sulfate. After 2 heating cycles, a yield >85% and a radiochemical purity {>=}96% were routinely obtained. Overall preparation time, including determination of radiochemical purity, is approximately 2.5 hr. The only equipment required is a thermostatically controlled block heater. Biodistribution of our I-131 product was indistinguishable from that distributed by the Nuclear Pharmacy at the University of Michigan, as was the radiochemical purity; the diagnostic efficacy matched that reported in the literature. The image quality obtained using I-123 mIBG was definitely superior, due to both the much higher count rate and the ideal imaging energy of I-123. On one occasion, the I-131 scan was equivocal, whereas the I-123 scan in the same patient was clearly positive. Retrospectively, for studies performed with I-123 mIBG using the {open_quotes}cold kit{close_quotes} method, the specificity and sensitivity both exceed 90%, correlating well with multiple studies reported in the literature. The preparation of I-123 mIBG in-house using this technique is recommended.« less

Applying quality by design principles to the small-scale preparation of the bone-targeting therapeutic radiopharmaceutical rhenium-188-HEDP.

PubMed

Lange, Rogier; Ter Heine, Rob; van der Gronde, Toon; Selles, Suzanne; de Klerk, John; Bloemendal, Haiko; Hendrikse, Harry

2016-07-30

Rhenium-188-HEDP ((188)Re-HEDP) is a therapeutic radiopharmaceutical for treatment of osteoblastic bone metastases. No standard procedure for the preparation of this radiopharmaceutical is available. Preparation conditions may influence the quality and in vivo behaviour of this product. In this study we investigate the effect of critical process parameters on product quality and stability of (188)Re-HEDP. A stepwise approach was used, based on the quality by design (QbD) concept of the ICH Q8 (Pharmaceutical Development) guideline. Potential critical process conditions were identified. Variables tested were the elution volume, the freshness of the eluate, the reaction temperature and time, and the stability of the product upon dilution and storage. The impact of each variable on radiochemical purity was investigated. The acceptable ranges were established by boundary testing. With 2ml eluate, adequate radiochemical purity and stability were found. Nine ml eluate yielded a product that was less stable. Using eluate stored for 24h resulted in acceptable radiochemical purity. Complexation for 30min at room temperature, at 60°C and at 100°C generated appropriate and stable products. A complexation time of 10min at 90°C was too short, whereas heating 60min resulted in products that passed quality control and were stable. Diluting the end product and storage at 32.5°C resulted in notable decomposition. Two boundary tests, an elution volume of 9ml and a heating time of 10min, yielded products of inadequate quality or stability. The product was found to be instable after dilution or when stored above room temperature. Our findings show that our previously developed preparation method falls well within the proven acceptable ranges. Applying QbD principles is feasible and worthwhile for the small-scale preparation of radiopharmaceuticals. Copyright © 2016 Elsevier B.V. All rights reserved.

Computing the Power-Density Spectrum for an Engineering Model

NASA Technical Reports Server (NTRS)

Dunn, H. J.

1982-01-01

Computer program for calculating of power-density spectrum (PDS) from data base generated by Advanced Continuous Simulation Language (ACSL) uses algorithm that employs fast Fourier transform (FFT) to calculate PDS of variable. Accomplished by first estimating autocovariance function of variable and then taking FFT of smoothed autocovariance function to obtain PDS. Fast-Fourier-transform technique conserves computer resources.

Comparison of macrocyclic and acyclic chelators for gallium-68 radiolabelling.

PubMed

Tsionou, Maria Iris; Knapp, Caroline E; Foley, Calum A; Munteanu, Catherine R; Cakebread, Andrew; Imberti, Cinzia; Eykyn, Thomas R; Young, Jennifer D; Paterson, Brett M; Blower, Philip J; Ma, Michelle T

2017-10-24

Gallium-68 ( 68 Ga) is a positron-emitting isotope used for clinical PET imaging of peptide receptor expression. 68 Ga radiopharmaceuticals used in molecular PET imaging consist of disease-targeting biomolecules tethered to chelators that complex 68 Ga 3+ . Ideally, the chelator will rapidly, quantitatively and stably coordinate 68 Ga 3+ at room temperature, near neutral pH and low chelator concentration, allowing for simple routine radiopharmaceutical formulation. Identification of chelators that fulfil these requirements will facilitate development of kit-based 68 Ga radiopharmaceuticals. Herein the reaction of a range of widely used macrocyclic and acyclic chelators with 68 Ga 3+ is reported. Radiochemical yields have been measured under conditions of varying chelator concentrations, pH (3.5 and 6.5) and temperature (25 and 90 °C). These chelators are: 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), 1,4,7-triazacyclononane macrocycles substituted with phosphonic (NOTP) and phosphinic (TRAP) groups at the amine, bis(2-hydroxybenzyl)ethylenediaminediacetic acid (HBED), a tris(hydroxypyridinone) containing three 1,6-dimethyl-3-hydroxypyridin-4-one groups (THP) and the hexadentate tris(hydroxamate) siderophore desferrioxamine-B (DFO). Competition studies have also been undertaken to assess relative complexation efficiencies of each chelator for 68 Ga 3+ under different pH and temperature conditions. Performing radiolabelling reactions at pH 6.5, 25 °C and 5-50 μM chelator concentration resulted in near quantitative radiochemical yields for all chelators, except DOTA. Radiochemical yields either decreased or were not substantially improved when the reactions were undertaken at lower pH or at higher temperature, except in the case of DOTA. THP and DFO were the most effective 68 Ga 3+ chelators at near-neutral pH and 25 °C, rapidly providing near-quantitative radiochemical yields at very low chelator concentrations. NOTP and HBED were only slightly less effective under these conditions. In competition studies with all other chelators, THP demonstrated highest reactivity for 68 Ga 3+ complexation under all conditions. These data point to THP possessing ideal properties for rapid, one-step kit-based syntheses of 68 Ga-biomolecules for molecular PET imaging. LC-MS and 1 H, 13 C{ 1 H} and 71 Ga NMR studies of HBED complexes of Ga 3+ showed that under the analytical conditions employed in this study, multiple HBED-bound Ga complexes exist. X-ray diffraction data indicated that crystals isolated from these solutions contained octahedral [Ga(HBED)(H 2 O)], with HBED coordinated in a pentadentate N 2 O 3 mode, with only one phenolic group coordinated to Ga 3+ , and the remaining coordination site occupied by a water molecule.

Consumption, Health Attitudes and Perception Toward Fast Food Among Arab Consumers in Kuwait: Gender Differences

PubMed Central

Musaiger, Abdulrahman O.

2014-01-01

This study aimed to investigate gender differences in the fast food intake, health attitudes, and perceptions of fast food among adult Arab consumers aged 19 to 65 years in Kuwait. A total of 499 consumers (252 males, 247 females) were selected at convenience from three shopping malls in Kuwait City. The consumers were interviewed using a specially designed questionnaire. The findings revealed that men were more frequently consumed fast food than women (p < 0.001). Men were significantly more likely to consume “double” burgers (52%) than women (29.9%) (P < 0.001). The great majority of consumers (95%) considered fast food harmful to health. However, the consumers were continued to intake fast food (92%), indicating that health information on fast food not necessarly affects their consumption. Local foods were more likely to be considered fast food if eaten as a sandwich or without a disposal container. It can be concluded that fast food perceptions are influenced by gender, media and socio-cultural factors. Nutrition education programmes should focus on nutritive values of the foods rather than on their “fast food” classification. PMID:25363129

Do intermittent diets provide physiological benefits over continuous diets for weight loss? A systematic review of clinical trials.

PubMed

Seimon, Radhika V; Roekenes, Jessica A; Zibellini, Jessica; Zhu, Benjamin; Gibson, Alice A; Hills, Andrew P; Wood, Rachel E; King, Neil A; Byrne, Nuala M; Sainsbury, Amanda

2015-12-15

Energy restriction induces physiological effects that hinder further weight loss. Thus, deliberate periods of energy balance during weight loss interventions may attenuate these adaptive responses to energy restriction and thereby increase the efficiency of weight loss (i.e. the amount of weight or fat lost per unit of energy deficit). To address this possibility, we systematically searched MEDLINE, PreMEDLINE, PubMed and Cinahl and reviewed adaptive responses to energy restriction in 40 publications involving humans of any age or body mass index that had undergone a diet involving intermittent energy restriction, 12 with direct comparison to continuous energy restriction. Included publications needed to measure one or more of body weight, body mass index, or body composition before and at the end of energy restriction. 31 of the 40 publications involved 'intermittent fasting' of 1-7-day periods of severe energy restriction. While intermittent fasting appears to produce similar effects to continuous energy restriction to reduce body weight, fat mass, fat-free mass and improve glucose homeostasis, and may reduce appetite, it does not appear to attenuate other adaptive responses to energy restriction or improve weight loss efficiency, albeit most of the reviewed publications were not powered to assess these outcomes. Intermittent fasting thus represents a valid--albeit apparently not superior--option to continuous energy restriction for weight loss. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

On the Effectiveness of Military Institutions: Historical Case Studies from World War I, The Interwar Period and World War II. Volume 1. World War I

DTIC Science & Technology

1986-04-01

fast -growing 3 numbers, for the first time In combat. But until the military and naval staffs had themselves defined what new weaponry was required...Scapa, Cromarty, and Rosyt’j, nor any of the smaller Fast Coast bases like Harwich, were on _ a par witrh Kiel and Wilhelmshaven, simply because history...could continue to complete the recently-ordered fast battleships and battlecruisers even in wartime, and deal with other demands. Over time, 3 however

Determination of rhenium in molybdenite by neutron-activation analysis.

PubMed

Terada, K; Yoshimura, Y; Osaki, S; Kiba, T

1967-01-01

A neutron-activation method is described for the determination of rhenium in molybdenite. Radiochemical separation by a carrier technique was carried out very rapidly by means of successive liquid-liquid extraction processes. The recovery of rhenium, which was determined by a spectrophotometric method, was about 93%. About 10 samples could be analysed within 6 hr in parallel runs.

Preparation of four 1,4-dihydropyridine derivatives (DHPs) labeled with carbon-14.

PubMed

Ahmadi Faghih, Mohammad Amin; Moslemin, Mohammad Hossein; Shirvani, Gholamhossein; Javaheri, Mohsen

2018-05-23

The importance of DHPs compounds and the need for examining the mechanism of their effect, mandated us to synthesize a number of carbon-14 labeled 1,4-dihydropyridine derivatives for pharmacological studies. Simple preparation and suitable radiochemical yield were advantages of this preparation. This article is protected by copyright. All rights reserved.

Rapid Radiochemical Method for Radium-226 in Building ...

EPA Pesticide Factsheets

Technical Fact Sheet Analysis Purpose: Qualitative analysis Technique: Alpha spectrometry Method Developed for: Radium-226 in building materials Method Selected for: SAM lists this method for qualitative analysis of radium-226 in concrete or brick building materials Summary of subject analytical method which will be posted to the SAM website to allow access to the method.

Rapid Radiochemical Method for Americium-241 in Building ...

EPA Pesticide Factsheets

Technical Fact Sheet Analysis Purpose: Qualitative analysis Technique: Alpha spectrometry Method Developed for: Americium-241 in building materials Method Selected for: SAM lists this method for qualitative analysis of americium-241 in concrete or brick building materials. Summary of subject analytical method which will be posted to the SAM website to allow access to the method.

A fast-neutron detection detector based on fission material and large sensitive 4H silicon carbide Schottky diode detector

NASA Astrophysics Data System (ADS)

Liu, Linyue; Liu, Jinliang; Zhang, Jianfu; Chen, Liang; Zhang, Xianpeng; Zhang, Zhongbing; Ruan, Jinlu; Jin, Peng; Bai, Song; Ouyang, Xiaoping

2017-12-01

Silicon carbide radiation detectors are attractive in the measurement of the total numbers of pulsed fast neutrons emitted from nuclear fusion and fission devices because of high neutron-gamma discrimination and good radiation resistance. A fast-neutron detection system was developed based on a large-area 4H-SiC Schottky diode detector and a 235U fission target. Excellent pulse-height spectra of fission fragments induced by mono-energy deuterium-tritium (D-T) fusion neutrons and continuous energy fission neutrons were obtained. The detector is proven to be a good candidate for pulsed fast neutron detection in a complex radiation field.

29 CFR 1918.84 - Bulling cargo.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.84 Bulling cargo. (a) Bulling cargo... from padeyes, straps, or beam clamps. Snatch blocks or straps shall not be made fast to batten cleats...

29 CFR 1915.165 - Ship's deck machinery.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping... claws (also known as chain stoppers) shall be made fast to the anchor chains. (2) The riding pawls shall...

Fluidized bed catalytic pyrolysis of eucalyptus over hzsm-5: effect of acid density and gallium modification on catalyst deactivation

USDA-ARS?s Scientific Manuscript database

Catalytic fast pyrolysis of eucalyptus wood was performed on a continuous laboratory scale fluidized bed fast pyrolysis system. Catalytic activity was monitored from use of fresh catalyst up to a cumulative biomass to catalyst ratio (B/C) of 4/1 over extruded pellets of three different ZSM-5 catalys...

Good, Fast, Cheap: How Centers of Teaching and Learning Can Capitalize in Today's Resource-Constrained Context

ERIC Educational Resources Information Center

Truong, Michael H.; Juillerat, Stephanie; Gin, Deborah H. C.

2016-01-01

This article provides leaders and educational developers of Centers for Teaching and Learning (CTL) with innovative and practical strategies on how to increase their centers' capacity and impact by focusing on quality, efficiency, and cost. This "good, fast, cheap" model represents a promising way that CTL can continue to grow, scale,…

Variations in gastric acid secretion during periods of fasting between two species of shark.

PubMed

Papastamatiou, Yannis P; Lowe, Christopher G

2005-06-01

Vertebrates differ in their regulation of gastric acid secretion during periods of fasting, yet it is unknown why these differences occur. Elasmobranch fishes are the earliest known vertebrates to develop an acid secreting stomach and as such may make a good comparative model for determining the causative factors behind these differences. We measured gastric pH and temperature continuously during periods of fasting in captive free-swimming nurse sharks (Ginglymostoma cirratum) using autonomous pH/temperature data-loggers. All nurse sharks secreted strong gastric acids (minimum pH 0.4) after feeding; however, for most of the sharks, pH increased to 8.2-8.7, 2-3 days after feeding. Half of the sharks also exhibited periodic oscillations in pH when the stomach was empty that ranged from 1.1 to 8.7 (acid secretion ceased for 11.3 +/- 4.3 h day(-1)). This is in contrast to the gastric pH changes observed from leopard sharks (Triakis semifasciata) in a previous study, where the stomach remains acidic during fasting. The leopard shark is a relatively active, more frequently feeding predator, and continuous acid secretion may increase digestive efficiency. In contrast, the nurse shark is less active and is thought to feed less frequently. Periodic cessation of acid secretion may be an energy conserving mechanism used by animals that feed infrequently and experience extended periods of fasting.

Decreased insulin response in dairy cows following a four-day fast to induce hepatic lipidosis.

PubMed

Oikawa, S; Oetzel, G R

2006-08-01

Negative energy balance has been implicated in the development of fatty liver, insulin resistance, and impaired health in dairy cows. A 4-d fasting model previously was reported to increase liver triglycerides more than 2.5-fold. The purpose of the present study was to evaluate insulin response in this fasting model. Nonlactating, nonpregnant Holstein cows were fasted for 4 d (6 cows) or fed continuously as control cows (4 cows). Samples were collected 5 d before fasting, during fasting, and immediately after the 4-d fast, 8 d after the fast, and 16 d after the fast. Fasted cows had greater liver triglyceride content (49.4 vs. 16.2 mg/g, wet-weight basis) at the end of the fasting period compared with control cows. Fasted cows also had increased plasma nonesterified fatty acid (NEFA) concentrations (1.24 vs. 0.21 mmol/L) and increased plasma beta-hydroxybutyrate (BHBA) concentrations at the end of the fasting period. Liver triglyceride, plasma NEFA, and plasma BHBA in fasted cows returned to prefasting concentrations by the end of the experiment. Plasma glucose concentrations were not affected by fasting. Plasma insulin concentrations were decreased (6.3 vs. 14.1 microU/mL) and insulin-stimulated blood glucose reduction was decreased (24.9 vs. 48.6%) in the fasted cows compared with control cows at the end of the fast, indicating reduced insulin response. Insulin response was negatively correlated with plasma NEFA and liver triglycerides. Decreased insulin response may be an important complication of negative energy balance and hepatic lipidosis.

Fasting: The History, Pathophysiology and Complications

PubMed Central

Kerndt, Peter R.; Naughton, James L.; Driscoll, Charles E.; Loxterkamp, David A.

1982-01-01

An appreciation of the physiology of fasting is essential to the understanding of therapeutic dietary interventions and the effect of food deprivation in various diseases. The practice of prolonged fasting for political or religious purposes is increasing, and a physician is likely to encounter such circumstances. Early in fasting weight loss is rapid, averaging 0.9 kg per day during the first week and slowing to 0.3 kg per day by the third week; early rapid weight loss is primarily due to negative sodium balance. Metabolically, early fasting is characterized by a high rate of gluconeogenesis with amino acids as the primary substrates. As fasting continues, progressive ketosis develops due to the mobilization and oxidation of fatty acids. As ketone levels rise they replace glucose as the primary energy source in the central nervous system, thereby decreasing the need for gluconeogenesis and sparing protein catabolism. Several hormonal changes occur during fasting, including a fall in insulin and T3 levels and a rise in glucagon and reverse T3 levels. Most studies of fasting have used obese persons and results may not always apply to lean persons. Medical complications seen in fasting include gout and urate nephrolithiasis, postural hypotension and cardiac arrhythmias. ImagesFigure 4. PMID:6758355

A Novel Approach to Resonant Absorption of the Fast Magnetohydrodynamic Eigenmodes of a Coronal Arcade

NASA Astrophysics Data System (ADS)

Hindman, Bradley W.; Jain, Rekha

2018-05-01

The arched field lines forming coronal arcades are often observed to undulate as magnetohydrodynamic waves propagate both across and along the magnetic field. These waves are most likely a combination of resonantly coupled fast magnetoacoustic waves and Alfvén waves. The coupling results in resonant absorption of the fast waves, converting fast wave energy into Alfvén waves. The fast eigenmodes of the arcade have proven difficult to compute or derive analytically, largely because of the mathematical complexity that the coupling introduces. When a traditional spectral decomposition is employed, the discrete spectrum associated with the fast eigenmodes is often subsumed into the continuous Alfvén spectrum. Thus fast eigenmodes become collective modes or quasi-modes. Here we present a spectral decomposition that treats the eigenmodes as having real frequencies but complex wavenumbers. Using this procedure we derive dispersion relations, spatial damping rates, and eigenfunctions for the resonant, fast eigenmodes of the arcade. We demonstrate that resonant absorption introduces a fast mode that would not exist otherwise. This new mode is heavily damped by resonant absorption, travelling only a few wavelengths before losing most of its energy.

Highly parallel demagnetization field calculation using the fast multipole method on tetrahedral meshes with continuous sources

NASA Astrophysics Data System (ADS)

Palmesi, P.; Exl, L.; Bruckner, F.; Abert, C.; Suess, D.

2017-11-01

The long-range magnetic field is the most time-consuming part in micromagnetic simulations. Computational improvements can relieve problems related to this bottleneck. This work presents an efficient implementation of the Fast Multipole Method [FMM] for the magnetic scalar potential as used in micromagnetics. The novelty lies in extending FMM to linearly magnetized tetrahedral sources making it interesting also for other areas of computational physics. We treat the near field directly and in use (exact) numerical integration on the multipole expansion in the far field. This approach tackles important issues like the vectorial and continuous nature of the magnetic field. By using FMM the calculations scale linearly in time and memory.

The Monitoring Case of Ground-Based Synthetic Aperture Radar with Frequency Modulated Continuous Wave System

NASA Astrophysics Data System (ADS)

Zhang, H. Y.; Zhai, Q. P.; Chen, L.; Liu, Y. J.; Zhou, K. Q.; Wang, Y. S.; Dou, Y. D.

2017-09-01

The features of the landslide geological disaster are wide distribution, variety, high frequency, high intensity, destructive and so on. It has become a natural disaster with harmful and wide range of influence. The technology of ground-based synthetic aperture radar is a novel deformation monitoring technology developed in recent years. The features of the technology are large monitoring area, high accuracy, long distance without contact and so on. In this paper, fast ground-based synthetic aperture radar (Fast-GBSAR) based on frequency modulated continuous wave (FMCW) system is used to collect the data of Ma Liuzui landslide in Chongqing. The device can reduce the atmospheric errors caused by rapidly changing environment. The landslide deformation can be monitored in severe weather conditions (for example, fog) by Fast-GBSAR with acquisition speed up to 5 seconds per time. The data of Ma Liuzui landslide in Chongqing are analyzed in this paper. The result verifies that the device can monitor landslide deformation under severe weather conditions.

Transportable, Low-Dose Active Fast-Neutron Imaging

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

Mihalczo, John T.; Wright, Michael C.; McConchie, Seth M.

2017-08-01

This document contains a description of the method of transportable, low-dose active fast-neutron imaging as developed by ORNL. The discussion begins with the technique and instrumentation and continues with the image reconstruction and analysis. The analysis discussion includes an example of how a gap smaller than the neutron production spot size and detector size can be detected and characterized depending upon the measurement time.

A Multisite Program Evaluation of Families and Schools Together (FAST): Continued Evidence of a Successful Multifamily Community-Based Prevention Program

ERIC Educational Resources Information Center

Crozier, Mary; Rokutani, Laurie; Russett, Jill L.; Godwin, Emilie; Banks, George E.

2010-01-01

Strong school and family ties have long shown success in influencing positive child development and lasting academic success. While a multitude of programs exist to help facilitate the school-family connection, one program in particular, Families and Schools Together, or FAST, stands out as an effective prevention program that is suitable for a…

U.S. Nuclear Cooperation with India: Issues for Congress

DTIC Science & Technology

2008-11-03

separation list: ! 8 indigenous Indian power reactors ! Fast Breeder test Reactor (FTBR) and Prototype Fast Breeder Reactors (PFBR) under construction...facilities like reprocessing and enrichment plants and breeder reactors could be viewed as providing a significant nonproliferation benefit because the... breeder reactors would support the 2002 U.S. National Strategy to Combat Weapons of Mass Destruction, in which the United States pledged to “continue to

Development of ORIGEN Libraries for Mixed Oxide (MOX) Fuel Assembly Designs

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

Mertyurek, Ugur; Gauld, Ian C.

In this research, ORIGEN cross section libraries for reactor-grade mixed oxide (MOX) fuel assembly designs have been developed to provide fast and accurate depletion calculations to predict nuclide inventories, radiation sources and thermal decay heat information needed in safety evaluations and safeguards verification measurements of spent nuclear fuel. These ORIGEN libraries are generated using two-dimensional lattice physics assembly models that include enrichment zoning and cross section data based on ENDF/B-VII.0 evaluations. Using the SCALE depletion sequence, burnup-dependent cross sections are created for selected commercial reactor assembly designs and a representative range of reactor operating conditions, fuel enrichments, and fuel burnup.more » The burnup dependent cross sections are then interpolated to provide problem-dependent cross sections for ORIGEN, avoiding the need for time-consuming lattice physics calculations. The ORIGEN libraries for MOX assembly designs are validated against destructive radiochemical assay measurements of MOX fuel from the MALIBU international experimental program. This program included measurements of MOX fuel from a 15 × 15 pressurized water reactor assembly and a 9 × 9 boiling water reactor assembly. The ORIGEN MOX libraries are also compared against detailed assembly calculations from the Phase IV-B numerical MOX fuel burnup credit benchmark coordinated by the Nuclear Energy Agency within the Organization for Economic Cooperation and Development. Finally, the nuclide compositions calculated by ORIGEN using the MOX libraries are shown to be in good agreement with other physics codes and with experimental data.« less

Gross alpha and beta activity analyses in urine-a routine laboratory method for internal human radioactivity detection.

PubMed

Chen, Xiaowen; Zhao, Luqian; Qin, Hongran; Zhao, Meijia; Zhou, Yirui; Yang, Shuqiang; Su, Xu; Xu, Xiaohua

2014-05-01

The aim of this work was to develop a method to provide rapid results for humans with internal radioactive contamination. The authors hypothesized that valuable information could be obtained from gas proportional counter techniques by screening urine samples from potentially exposed individuals rapidly. Recommended gross alpha and beta activity screening methods generally employ gas proportional counting techniques. Based on International Standards Organization (ISO) methods, improvements were made in the evaporation process to develop a method to provide rapid results, adequate sensitivity, and minimum sample preparation and operator intervention for humans with internal radioactive contamination. The method described by an American National Standards Institute publication was used to calibrate the gas proportional counter, and urine samples from patients with or without radionuclide treatment were measured to validate the method. By improving the evaporation process, the time required to perform the assay was reduced dramatically. Compared with the reference data, the results of the validation samples were very satisfactory with respect to gross-alpha and gross-beta activities. The gas flow proportional counting method described here has the potential for radioactivity monitoring in the body. This method was easy, efficient, and fast, and its application is of great utility in determining whether a sample should be analyzed by a more complicated method, for example radiochemical and/or γ-spectroscopy. In the future, it may be used commonly in medical examination and nuclear emergency treatment.Health Phys. 106(5):000-000; 2014.

Development of ORIGEN Libraries for Mixed Oxide (MOX) Fuel Assembly Designs

DOE PAGES

Mertyurek, Ugur; Gauld, Ian C.

2015-12-24

In this research, ORIGEN cross section libraries for reactor-grade mixed oxide (MOX) fuel assembly designs have been developed to provide fast and accurate depletion calculations to predict nuclide inventories, radiation sources and thermal decay heat information needed in safety evaluations and safeguards verification measurements of spent nuclear fuel. These ORIGEN libraries are generated using two-dimensional lattice physics assembly models that include enrichment zoning and cross section data based on ENDF/B-VII.0 evaluations. Using the SCALE depletion sequence, burnup-dependent cross sections are created for selected commercial reactor assembly designs and a representative range of reactor operating conditions, fuel enrichments, and fuel burnup.more » The burnup dependent cross sections are then interpolated to provide problem-dependent cross sections for ORIGEN, avoiding the need for time-consuming lattice physics calculations. The ORIGEN libraries for MOX assembly designs are validated against destructive radiochemical assay measurements of MOX fuel from the MALIBU international experimental program. This program included measurements of MOX fuel from a 15 × 15 pressurized water reactor assembly and a 9 × 9 boiling water reactor assembly. The ORIGEN MOX libraries are also compared against detailed assembly calculations from the Phase IV-B numerical MOX fuel burnup credit benchmark coordinated by the Nuclear Energy Agency within the Organization for Economic Cooperation and Development. Finally, the nuclide compositions calculated by ORIGEN using the MOX libraries are shown to be in good agreement with other physics codes and with experimental data.« less

Rapid Radiochemical Method for Total Radiostrontium (Sr-90) ...

EPA Pesticide Factsheets

Technical Fact Sheet Analysis Purpose: Qualitative analysis Technique: Beta counting Method Developed for: Strontium-89 and strontium-90 in building materials Method Selected for: SAM lists this method for qualitative analysis of strontium-89 and strontium-90 in concrete or brick building materials Summary of subject analytical method which will be posted to the SAM website to allow access to the method.

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.

Simultaneous fast scanning XRF, dark field, phase-, and absorption contrast tomography

NASA Astrophysics Data System (ADS)

Medjoubi, Kadda; Bonissent, Alain; Leclercq, Nicolas; Langlois, Florent; Mercère, Pascal; Somogyi, Andrea

2013-09-01

Scanning hard X-ray nanoprobe imaging provides a unique tool for probing specimens with high sensitivity and large penetration depth. Moreover, the combination of complementary techniques such as X-ray fluorescence, absorption, phase contrast and dark field imaging gives complete quantitative information on the sample structure, composition and chemistry. The multi-technique "FLYSCAN" data acquisition scheme developed at Synchrotron SOLEIL permits to perform fast continuous scanning imaging and as such makes scanning tomography techniques feasible in a time-frame well-adapted to typical user experiments. Here we present the recent results of simultaneous fast scanning multi-technique tomography performed at Soleil. This fast scanning scheme will be implemented at the Nanoscopium beamline for large field of view 2D and 3D multimodal imaging.

Optimization of 18 F-syntheses using 19 F-reagents at tracer-level concentrations and liquid chromatography/tandem mass spectrometry analysis: Improved synthesis of [18 F]MDL100907.

PubMed

Zhang, Xiang; Dunlow, Ryan; Blackman, Burchelle N; Swenson, Rolf E

2018-05-15

Traditional radiosynthetic optimization faces the challenges of high radiation exposure, cost, and inability to perform serial reactions due to tracer decay. To accelerate tracer development, we have developed a strategy to simulate radioactive 18 F-syntheses by using tracer-level (nanomolar) non-radioactive 19 F-reagents and LC-MS/MS analysis. The methodology was validated with fallypride synthesis under tracer-level 19 F-conditions, which showed reproducible and comparable results with radiosynthesis, and proved the feasibility of this process. Using this approach, the synthesis of [ 18 F]MDL100907 was optimized under 19 F-conditions with greatly improved yield. The best conditions were successfully transferred to radiosynthesis. A radiochemical yield of 19% to 22% was achieved with the radiochemical purity >99% and the molar activity 38.8 to 53.6 GBq/ μmol (n = 3). The tracer-level 19 F-approach provides a high-throughput and cost-effective process to optimize radiosynthesis with reduced radiation exposure. This new method allows medicinal and synthetic chemists to optimize radiolabeling conditions without the need to use radioactivity. Copyright © 2018 John Wiley & Sons, Ltd.

Chromatographic separation of the theranostic radionuclide 111Ag from a proton irradiated thorium matrix

DOE PAGES

Mastren, Tara; Radchenko, Valery; Engle, Jonathan W.; ...

2017-10-30

Column chromatographic methods have been developed to separate no-carrier-added 111Ag from proton irradiated thorium targets and associated fission products as an ancillary process to an existing 225Ac separation design. In this paper, we report the separation of 111Ag both prior and subsequent to 225Ac recovery using CL resin, a solvent impregnated resin (SIR) that carries an organic solution of alkyl phosphine sulfides (R 3P = S) and alkyl phosphine oxides (R 3P = O). The recovery yield of 111Ag was 93 ± 9% with a radiochemical purity of 99.9% (prior) and 87 ± 9% with a radiochemical purity of 99.9%more » (subsequent to) 225Ac recovery. Both processes were successfully performed with insignificant impacts on 225Ac yields or quality. Measured equilibrium distribution coefficients for silver and ruthenium (a residual contaminant) on CL resin in hydrochloric and nitric acid media are reported, to the best of our knowledge, for the first time. Finally and additionally, measured cross sections for the production of 111Ag and 110mAg for the 232Th(p,f) 110m,111Ag reactions are reported within.« less

Synthesis of carbon-11-labeled bivalent β-carbolines as new PET agents for imaging of cholinesterase in Alzheimer's disease.

PubMed

Wang, Min; Zheng, David X; Gao, Mingzhang; Hutchins, Gary D; Zheng, Qi-Huang

2011-04-01

Carbon-11-labeled bivalent β-carbolines, 9,9'-(pentane-1,5-diyl)bis(2-[(11)C]methyl-9H-pyrido[3,4-b]indol-2-ium)iodide ([(11)C]2a), 9,9'-(nonane-1,9-diyl)bis(2-[(11)C]methyl-9H-pyrido[3,4-b]indol-2-ium)iodide ([(11)C]2b), 9,9'-(dodecane-1,12-diyl)bis(2-[(11)C]methyl-9H-pyrido[3,4-b]indol-2-ium)iodide ([(11)C]2c) and 1,9-bis(2-[(11)C]methyl-3,4-dihydro-1H-pyrido[3,4-b]indol-9(2H)-yl)nonane ([(11)C]3), were prepared by N-[(11)C]methylation of their corresponding amine precursors using [(11)C]CH(3)I and isolated by either a simplified solid-phase extraction (SPE) method or HPLC in 40-60% radiochemical yields based on [(11)C]CO(2) and decay corrected to end of bombardment (EOB). The overall synthesis time from EOB was 20-30min, the radiochemical purity was >99%, and the specific activity at end of synthesis (EOS) was 185-370 GBq/μmol. Copyright © 2011 Elsevier Ltd. All rights reserved.

Automated solid-phase radiofluorination using polymer-supported phosphazenes.

PubMed

Mathiessen, Bente; Zhuravlev, Fedor

2013-08-30

The polymer supported phosphazene bases PS-P₂(tBu) and the novel PS-P₂(PEG) allowed for efficient extraction of [¹⁸F]F⁻ from proton irradiated [¹⁸O]H₂O and subsequent radiofluorination of a broad range of substrates directly on the resin. The highest radiochemical yields were obtained with aliphatic sulfonates (69%) and bromides (42%); the total radiosynthesis time was 35-45 min. The multivariate analysis showed that the radiochemical yields and purities were controlled by the resin load, reaction temperature, and column packing effects. The resins could be reused several times with the same or different substrates. The fully automated on-column radiofluorination methodology was applied to the radiosynthesis of the important PET radiotracers [¹⁸F]FLT and [¹⁸F]FDG. The latter was produced with 40% yield on a 120 GBq scale and passed GMP-regulated quality control required for commercial production of [1¹⁸F]FDG. The combination of compact form factor, simplicity of [¹⁸F]F⁻ recovery and processing, and column reusability can make solid phase radiofluorination an attractive radiochemistry platform for the emerging dose-on-demand instruments for bedside production of PET radiotracers.

Application of Microreactor to the Preparation of C-11-Labeled Compounds via O-[11C]Methylation with [11C]CH3I: Rapid Synthesis of [11C]Raclopride.

PubMed

Kawashima, Hidekazu; Kimura, Hiroyuki; Nakaya, Yuta; Tomatsu, Kenji; Arimitsu, Kenji; Nakanishi, Hiroaki; Ozeki, Eiichi; Kuge, Yuji; Saji, Hideo

2015-01-01

A new radiolabeling method using a microreactor was developed for the rapid synthesis of [(11)C]raclopride. A chip bearing a Y-shaped mixing junction with a 200 µm (width)×20 µm (depth)×250 mm (length) flow channel was designed, and the efficiency of O-[11C]methylation was evaluated. Dimethyl sulfoxide solutions containing the O-desmethyl precursor or [11C]CH3I were introduced into separate injection ports by infusion syringes, and the radiochemical yields were measured under various conditions. The decay-corrected radiochemical yield of microreactor-derived [11C]raclopride reached 12% in 20 s at 25 °C, which was observed to increase with increasing temperature. In contrast, batch synthesis at 25 °C produced a yield of 5%: this indicates that this device could effectively achieve O-[11C]methylation in a shorter period of time. The microreactor technique may facilitate simple and efficient routine production of 11C-labeled compounds via O-[11C]methylation with [11C]CH3I.

The Use of Isotope Dilution Alpha Spectrometry and Liquid Scintillation Counting to Determine Radionuclides in Environmental Samples (abstract)

NASA Astrophysics Data System (ADS)

Bylyku, Elida

2009-04-01

In Albania in recent years it has been of increasing interest to determine various pollutants in the environment and their possible effects on human health. The radiochemical procedure used to identify Pu, Am, U, Th, and Sr radioisotopes in soil, sediment, water, coal, and milk samples is described. The analysis is carried out in the presence of respective tracer solutions and combines the procedure for Pu analysis based on anion exchange, the selective method for Sr isolation based on extraction chromatography using Sr-Spec resin, and the application of the TRU-Spec column for separation of Am fraction. An acid digestion method has been applied for the decomposition of samples. The radiochemical procedure involves the separation of Pu from Th, Am, and Sr by anion exchange, followed by the preconcentration of Am and Sr by coprecipitation with calcium oxalate. Am is separated from Sr by extraction chromatography. Uranium is separated from the bulk elements by liquid-liquid extraction using UTEVA® resin. Thin sources for alpha spectrometric measurements are prepared by microprecipitation with NdF3. Two International Atomic Energy Agency reference materials were analyzed in parallel with the samples.

Synthesis and Biological Evaluation of (S)-Amino-2-methyl-4-[(76)Br]bromo-3-(E)-butenoic Acid (BrVAIB) for Brain Tumor Imaging.

PubMed

Burkemper, Jennifer L; Huang, Chaofeng; Li, Aixiao; Yuan, Liya; Rich, Keith; McConathy, Jonathan; Lapi, Suzanne E

2015-11-12

The novel compound, (S)-amino-2-methyl-4-[(76)Br]bromo-3-(E)-butenoic acid (BrVAIB, [(76)Br]5), was characterized against the known system A tracer, IVAIB ([(123)I]8). [(76)Br]5 was prepared in a 51% ± 19% radiochemical yield with high radiochemical purity (≥98%). The biological properties of [(76)Br]5 were compared with those of [(123)I]8. Results showed that [(76)Br]5 undergoes mixed amino acid transport by system A and system L transport, while [(123)I]8 had less uptake by system L. [(76)Br]5 demonstrated higher uptake than [(123)I]8 in DBT tumors 1 h after injection (3.7 ± 0.4% ID/g vs 1.5 ± 0.3% ID/g) and also showed higher uptake vs [(123)I]8 in normal brain. Small animal PET studies with [(76)Br]5 demonstrated good tumor visualization of intracranial DBTs up to 24 h with clearance from normal tissues. These results indicate that [(76)Br]5 is a promising PET tracer for brain tumor imaging and lead compound for a mixed system A and system L transport substrate.

Synthesis and biological studies of positron-emitting radiopharmaceuticals

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

Dischino, D.D.

The development and clinical evaluation of two-positron emitting radiopharmaceuticals designed to image myelin in humans is reported. Carbon-11-labeled benzyl methyl ether was synthesized by the reaction of carbon-11-labeled methanol and benzyl chloride in dimethyl sulfoxide containing powdered potassium hydroxide in a radiochemical yield of 43% and a synthesis and purification time of 40 minutes. Carbon-11-labeled diphenylmethanol was synthesized by the reaction of carbon-11-labeled carbon dioxide and phenyllithium followed by the reduction of the carbon-11-labeled intermediate to diphenylmethanol via lithium aluminum hydride in a radiochemical yield of 71% and a synthesis and purification time of 38 minutes. Carbon-11-labeled benzyl methyl ethermore » and diphenylmethanol were each evaluated as myelin imaging agents in three patients with multiple sclerosis via positron-emission tomography. In two out of three patients studied with carbon-11-labeled benzyl methyl ether, the distribution of activity in the brain was not consistent with local lipid content. A new synthesis of carbon-11-labeled-DL-phenylalanine labeled in the benzylic position and the synthesis of fluorine-18-labeled 1-(2-nitro-1-imidazolyl)-3-fluoro-2-propanol, a potential in vivo marker of hypoxic tissue, are reported.« less

Simplified and robust one-step radiosynthesis of [18 F]DCFPyL via direct radiofluorination and cartridge-based purification.

PubMed

Dornan, Mark H; Simard, José-Mathieu; Leblond, Antoine; Juneau, Daniel; Delouya, Guila; Saad, Fred; Ménard, Cynthia; DaSilva, Jean N

2018-05-02

[ 18 F]DCFPyL is a clinical-stage PET radiotracer used to image prostate cancer. This report details the efficient production of [ 18 F]DCFPyL using single-step direct radiofluorination, without the use of carboxylic acid-protecting groups. Radiolabeling reaction optimization studies revealed an inverse correlation between the amount of precursor used and the radiochemical yield. This simplified approach enabled automated preparation of [ 18 F]DCFPyL within 28 minutes using HPLC purification (26% ± 6%, at EOS, n = 4), which was then scaled up for large-batch production to generate 1.46 ± 0.23 Ci of [ 18 F]DCFPyL at EOS (n = 7) in high molar activity (37 933 ± 4158 mCi/μmol, 1403 ± 153 GBq/μmol, at EOS, n = 7). Further, this work enabled the development of [ 18 F]DCFPyL production in 21 minutes using an easy cartridge-based purification (25% ± 9% radiochemical yield, at EOS, n = 3). Copyright © 2018 John Wiley & Sons, Ltd.

Chromatographic separation of the theranostic radionuclide 111Ag from a proton irradiated thorium matrix

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

Mastren, Tara; Radchenko, Valery; Engle, Jonathan W.

Column chromatographic methods have been developed to separate no-carrier-added 111Ag from proton irradiated thorium targets and associated fission products as an ancillary process to an existing 225Ac separation design. In this paper, we report the separation of 111Ag both prior and subsequent to 225Ac recovery using CL resin, a solvent impregnated resin (SIR) that carries an organic solution of alkyl phosphine sulfides (R 3P = S) and alkyl phosphine oxides (R 3P = O). The recovery yield of 111Ag was 93 ± 9% with a radiochemical purity of 99.9% (prior) and 87 ± 9% with a radiochemical purity of 99.9%more » (subsequent to) 225Ac recovery. Both processes were successfully performed with insignificant impacts on 225Ac yields or quality. Measured equilibrium distribution coefficients for silver and ruthenium (a residual contaminant) on CL resin in hydrochloric and nitric acid media are reported, to the best of our knowledge, for the first time. Finally and additionally, measured cross sections for the production of 111Ag and 110mAg for the 232Th(p,f) 110m,111Ag reactions are reported within.« less

Fast Flux Watch: A mechanism for online detection of fast flux networks.

PubMed

Al-Duwairi, Basheer N; Al-Hammouri, Ahmad T

2014-07-01

Fast flux networks represent a special type of botnets that are used to provide highly available web services to a backend server, which usually hosts malicious content. Detection of fast flux networks continues to be a challenging issue because of the similar behavior between these networks and other legitimate infrastructures, such as CDNs and server farms. This paper proposes Fast Flux Watch (FF-Watch), a mechanism for online detection of fast flux agents. FF-Watch is envisioned to exist as a software agent at leaf routers that connect stub networks to the Internet. The core mechanism of FF-Watch is based on the inherent feature of fast flux networks: flux agents within stub networks take the role of relaying client requests to point-of-sale websites of spam campaigns. The main idea of FF-Watch is to correlate incoming TCP connection requests to flux agents within a stub network with outgoing TCP connection requests from the same agents to the point-of-sale website. Theoretical and traffic trace driven analysis shows that the proposed mechanism can be utilized to efficiently detect fast flux agents within a stub network.

Reading strategies of fast and slow readers.

PubMed

Haberlandt, K F; Graesser, A C; Schneider, N J

1989-09-01

In three subject-paced experiments we evaluated reading patterns at the word, line, and sentence level for fast and slow readers. A moving-window method was used to collect word reading times for natural texts. At the word level, reading times of word N were influenced by features of word N-1 for fast readers but not for slow readers. The lag effect exhibited by fast readers indicates that they continue to process a word when it is no longer in view, thus limiting the notion of immediate processing. Contrary to our initial expectation that fast readers would process only a single new argument from a sentence, whereas slow readers would process several new arguments, we found that both reader groups adopted a many-argument strategy. However, fast and slow readers differed in terms of the text units (lines vs. sentences) defining the new-argument effects: Fast readers exhibited greater new-argument effects relative to lines, whereas slow readers exhibited greater new-argument effects relative to sentences. Specifically, slow readers integrated the new arguments primarily at the end of the sentence, whereas fast readers did so at line boundaries. These results are discussed in terms of a buffer-and-integrate model of reading comprehension.

Patterns and Predictors of Fast Food Consumption After Acute Myocardial Infarction

PubMed Central

Salisbury, Adam C.; Chan, Paul S.; Gosch, Kensey L.; Buchanan, Donna M.; Spertus, John A.

2011-01-01

Although fast food is affordable and convenient, it is also high in calories, saturated fat and sodium. The frequency of fast food intake at the time of, and after, acute myocardial infarction (AMI) is modifiable. However, patterns of fast food intake and characteristics associated with its consumption among AMI patients are unknown. We studied fast food consumption at the time of AMI and 6 months later in 2481 patients from the prospective, 24-center TRIUMPH study of AMI patients. Fast food intake was categorized as frequent (≥ weekly) vs. infrequent (< weekly). Multivariable log-binomial regression was used to identify patient characteristics associated with frequent fast food intake 6 months after AMI. At baseline, 884 patients (36%) reported frequent fast food intake, which decreased to 503 (20%) 6 months after discharge (p-value <0.001). Male sex, white race, lack of college education, current employment and dyslipidemia were independently associated with frequent fast food intake 6 months after AMI. In contrast, older patients and those who had coronary bypass surgery were less likely to eat fast food frequently. Documentation of discharge dietary counseling was not associated with 6-month fast food intake. In conclusion, fast food consumption by AMI patients declined 6 months after the index hospitalization, but certain populations, including younger patients, men, those currently working, and less educated patients were more likely to consume fast food, at least weekly, during follow-up. Novel interventions that go beyond traditional dietary counseling may be needed to address continued fast food consumption after AMI in these patients. PMID:21306695

Fully automated SPE-based synthesis and purification of 2-[18F]fluoroethyl-choline for human use.

PubMed

Schmaljohann, Jörn; Schirrmacher, Esther; Wängler, Björn; Wängler, Carmen; Schirrmacher, Ralf; Guhlke, Stefan

2011-02-01

2-[(18)F]Fluoroethyl-choline ([(18)F]FECH) is a promising tracer for the detection of prostate cancer as well as brain tumors with positron emission tomography (PET). [(18)F]FECH is actively transported into mammalian cells, becomes phosphorylated by choline kinase and gets incorporated into the cell membrane after being metabolized to phosphatidylcholine. So far, its synthesis is a two-step procedure involving at least one HPLC purification step. To allow a wider dissemination of this tracer, finding a purification method avoiding HPLC is highly desirable and would result in easier accessibility and more reliable production of [(18)F]FECH. [(18)F]FECH was synthesized by reaction of 2-bromo-1-[(18)F]fluoroethane ([(18)F]BFE) with dimethylaminoethanol (DMAE) in DMSO. We applied a novel and very reliable work-up procedure for the synthesis of [(18)F]BFE. Based on a combination of three different solid-phase cartridges, the purification of [(18)F]BFE from its precursor 2-bromoethyl-4-nitrobenzenesulfonate (BENos) could be achieved without using HPLC. Following the subsequent reaction of the purified [(18)F]BFE with DMAE, the final product [(18)F]FECH was obtained as a sterile solution by passing the crude reaction mixture through a combination of two CM plus cartridges and a sterile filter. The fully automated synthesis was performed using as well a Raytest SynChrom module (Raytest, Germany) or a Scintomics HotboxIII module (Scintomics, Germany). The radiotracer [(18)F]FECH can be synthesized in reliable radiochemical yields (RCY) of 37±5% (Synchrom module) and 33±5% (Hotbox III unit) in less than 1 h using these two fully automated commercially available synthesis units without HPLC involvement for purification. Detailed quality control of the final injectable [(18)F]FECH solution proved the high radiochemical purity and the absence of Kryptofix2.2.2, DMAE and DMSO used in the course of synthesis. Sterility and bacterial endotoxin testing following standard procedures verified that the described production method for [(18)F]FECH is suitable for human applications. The routine production of [(18)F]FECH with sufficient RCYs was established by reliable and fast solid-phase extraction purifications of both the secondary labeling precursor [(18)F]BFE and the final product [(18)F]FECH, avoiding complex and sensitive HPLC equipment. The purity of the product was >95%, rendering the tracer suitable for human application. The newly developed purification procedure for [(18)F]BFE significantly reduces the complexity of the automated synthesis unit, hence reducing the cost for routine production in a clinical setup and allowing easy transfer to different synthesis modules. Copyright © 2011 Elsevier Inc. All rights reserved.

Continuous glucose profiles in obese and normal-weight pregnant women on a controlled diet: metabolic determinants of fetal growth.

PubMed

Harmon, Kristin A; Gerard, Lori; Jensen, Dalan R; Kealey, Elizabeth H; Hernandez, Teri L; Reece, Melanie S; Barbour, Linda A; Bessesen, Daniel H

2011-10-01

We sought to define 24-h glycemia in normal-weight and obese pregnant women using continuous glucose monitoring (CGM) while they consumed a habitual and controlled diet both early and late in pregnancy. Glycemia was prospectively measured in early (15.7 ± 2.0 weeks' gestation) and late (27.7 ± 1.7 weeks' gestation) pregnancy in normal-weight (n = 22) and obese (n = 16) pregnant women on an ad libitum and controlled diet. Fasting glucose, triglycerides (early pregnancy only), nonesterified fatty acids (FFAs), and insulin also were measured. The 24-h glucose area under the curve was higher in obese women than in normal-weight women both early and late in pregnancy despite controlled diets. Nearly all fasting and postprandial glycemic parameters were higher in the obese women later in pregnancy, as were fasting insulin, triglycerides, and FFAs. Infants born to obese mothers had greater adiposity. Maternal BMI (r = 0.54, P = 0.01), late average daytime glucose (r = 0.48, P < 0.05), and late fasting insulin (r = 0.49, P < 0.05) correlated with infant percentage body fat. However, early fasting triglycerides (r = 0.67, P < 0.001) and late fasting FFAs (r = 0.54, P < 0.01) were even stronger correlates. This is the first study to demonstrate that obese women without diabetes have higher daytime and nocturnal glucose profiles than normal-weight women despite a controlled diet both early and late in gestation. Body fat in infants, not birth weight, was related to maternal BMI, glucose, insulin, and FFAs, but triglycerides were the strongest predictor. These metabolic findings may explain higher rates of infant macrosomia in obese women, which might be targeted in trials to prevent excess fetal growth.

Distinct timing mechanisms produce discrete and continuous movements.

PubMed

Huys, Raoul; Studenka, Breanna E; Rheaume, Nicole L; Zelaznik, Howard N; Jirsa, Viktor K

2008-04-25

The differentiation of discrete and continuous movement is one of the pillars of motor behavior classification. Discrete movements have a definite beginning and end, whereas continuous movements do not have such discriminable end points. In the past decade there has been vigorous debate whether this classification implies different control processes. This debate up until the present has been empirically based. Here, we present an unambiguous non-empirical classification based on theorems in dynamical system theory that sets discrete and continuous movements apart. Through computational simulations of representative modes of each class and topological analysis of the flow in state space, we show that distinct control mechanisms underwrite discrete and fast rhythmic movements. In particular, we demonstrate that discrete movements require a time keeper while fast rhythmic movements do not. We validate our computational findings experimentally using a behavioral paradigm in which human participants performed finger flexion-extension movements at various movement paces and under different instructions. Our results demonstrate that the human motor system employs different timing control mechanisms (presumably via differential recruitment of neural subsystems) to accomplish varying behavioral functions such as speed constraints.

EnvironmentalWaveletTool: Continuous and discrete wavelet analysis and filtering for environmental time series

NASA Astrophysics Data System (ADS)

Galiana-Merino, J. J.; Pla, C.; Fernandez-Cortes, A.; Cuezva, S.; Ortiz, J.; Benavente, D.

2014-10-01

A MATLAB-based computer code has been developed for the simultaneous wavelet analysis and filtering of several environmental time series, particularly focused on the analyses of cave monitoring data. The continuous wavelet transform, the discrete wavelet transform and the discrete wavelet packet transform have been implemented to provide a fast and precise time-period examination of the time series at different period bands. Moreover, statistic methods to examine the relation between two signals have been included. Finally, the entropy of curves and splines based methods have also been developed for segmenting and modeling the analyzed time series. All these methods together provide a user-friendly and fast program for the environmental signal analysis, with useful, practical and understandable results.

Prompt and delayed NAA techniques for the characterization of specimen bank materials.

PubMed

Rossbach, M; Stoeppler, M; Byrne, A R

1993-11-01

The combined application of instrumental-, radiochemical- and prompt gamma neutron activation analysis to two spruce shoot materials from the German Environmental Specimen Bank (ESB) resulted in information on 50 elements, covering more than 50% of the total mass. Comparison of the element concentrations in the 'fingerprint' mode clearly indicated a different status of heavy metal pollution at the two distinct collecting sites.

Modeled Neutron and Charged-Particle Induced Nuclear Reaction Cross Sections for Radiochemistry in the Region of Yttrium, Zirconium, Niobium, and Molybdenum

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

Hoffman, R D; Kelley, K; Dietrich, F S

2006-06-13

We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron, proton, and deuteron induced nuclear reaction cross sections for targets ranging from strontium (Z = 38) to rhodium (Z = 45).

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.

Radiochemical monitoring of water after the Cannikin Event, Amchitka Island, Alaska, May 1974

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

Thordarson, W.; Ballance, W.C.

During May 1974, the U. S. Geological Survey collected water samples from Amchitka Island, Alaska. Tritium determinations were made on 99 water samples, and dissolved gross alpha and gross beta/gamma determinations were made on 34 water samples. No appreciable differences were found between the data obtained in May 1974 and the data obtained before the Cannikin nuclear explosion.

Radiochemical monitoring of water after the Cannikin event, Amchitka Island, Alaska, May 1974

USGS Publications Warehouse

Thordarson, William; Ballance, Wilbur C.

1976-01-01

During May 1974, the U.S. Geological Survey collected water samples from Amchitka Island, Alaska. Tritium determinations were made on 99 water samples, and dissolved gross alpha and gross beta/gamma determinations were made on 34 water samples, No appreciable differences were found between the data obtained in May 1974 and the data obtained before the Cannikin nuclear explosion.

DATATOC: a novel conjugate for kit-type 68Ga labelling of TOC at ambient temperature.

PubMed

Seemann, Johanna; Waldron, Bradley; Parker, David; Roesch, Frank

2017-01-01

The widespread acceptance and application of 68 Ga-PET depends on our ability to develop radiopharmaceuticals that can be prepared in a convenient and suitable manner. A kit-type labelling protocol provides such characteristics and requires chelators that can be radiolabelled under exceptionally mild conditions. Recently the DATA chelators have been introduced that fulfil these requirements. In continuing their development, the synthesis and radiolabelling of the first DATA bifunctional chelator (BFC) and peptide conjugate are described. A BFC derived from the DATA ligand (2,2'-(6-((carboxymethyl)amino)-1,4-diazepane-1,4-diyl)diacetic acid) has been synthesised in five steps from simple building blocks, with an overall yield of 8 %. DATA M5 -3 t Bu (5-[1,4-Bis-tert-butoxycarbonylmethyl-6-(tert-butoxycarbonylmethyl-methyl-amino)-[1, 4]diazepan-6-yl]-pentanoic acid) has been coupled to [DPhe 1 ][Tyr 3 ]-octreotide (TOC) and the resulting peptide conjugate (DATATOC) radiolabelled with purified 68 Ga derived via four different 68 Ge/ 68 Ga generator post-processing (PP) methods. The stability and lipophilicity of the radiotracer have been assessed and a kit-type formulation for radiolabelling evaluated. 68 Ga-DATATOC has been prepared with a > 95 % radiochemical yield (RCY) within 1 (fractionated and acetone-PP) and 10 min (ethanol- and NaCl-PP) at 23 °C (pH 4.2-4.9, 13 nmol). The radiolabelled peptide is stable in the presence of human serum. Lipophilicity of 68 Ga-DATATOC was calculated as logP = -3.2 ± 0.3, with a HPLC retention time ( t R  = 10.4 min) similar to 68 Ga-DOTATOC (logP = -2.9 ± 0.4, t R  = 10.3 min). Kit-type labelling from a lyophilised solid using acetone-PP based labelling achieves > 95 % RCY in 10 min at 23 °C. The favourable labelling properties of the DATA chelators have been retained for DATATOC. High radiochemical purity can be achieved at 23 °C in less than 1 min and from a kit formulation. The speed, reliability, ease, flexibility and simplicity with which 68 Ga-DATATOC can be prepared makes it a very attractive alternative to current standards.

N-(4-[18F]fluorobenzyl)cholylglycine, a novel tracer for PET of enterohepatic circulation of bile acids: Radiosynthesis and proof-of-concept studies in rats.

PubMed

Frisch, Kim; Stimson, Damion H R; Venkatachalam, Taracad; Pierens, Gregory K; Keiding, Susanne; Reutens, David; Bhalla, Rajiv

2018-05-04

Enterohepatic circulation (EHC) of conjugated bile acids is an important physiological process crucial for regulation of intracellular concentrations of bile acids and their function as detergents and signal carriers. Only few bile acid-derived imaging agents have been synthesized and hitherto none have been evaluated for studies of EHC. We hypothesized that N-(4-[ 18 F]fluorobenzyl)cholylglycine ([ 18 F]FBCGly), a novel fluorine-18 labeled derivative of endogenous cholylglycine, would be a suitable tracer for PET of the EHC of conjugated bile acids, and we report here a radiosynthesis of [ 18 F]FBCGly and a proof-of-concept study by PET/MR in rats. A radiosynthesis of [ 18 F]FBCGly was developed based on reductive alkylation of glycine with 4-[ 18 F]fluorobenzaldehyde followed by coupling to cholic acid. [ 18 F]FBCGly was investigated in vivo by dynamic PET/MR in anesthetized rats; untreated or treated with cholyltaurine or rifampicin. Possible in vivo metabolites of [ 18 F]FBCGly were investigated by analysis of blood and bile samples, and the stability of [ 18 F]FBCGly towards enzymatic de-conjugation by Cholylglycine Hydrolase was tested in vitro. [ 18 F]FBCGly was produced with a radiochemical purity of 96% ± 1% and a non-decay corrected radiochemical yield of 1.0% ± 0.3% (mean ± SD; n = 12). PET/MR studies showed that i.v.-administrated [ 18 F]FBCGly underwent EHC within 40-60 min with a rapid transhepatic transport from blood to bile. In untreated rats, the radioactivity concentration of [ 18 F]FBCGly was approximately 15 times higher in bile than in liver tissue. Cholyltaurine and rifampicin inhibited the biliary secretion of [ 18 F]FBCGly. No fluorine-18 metabolites of [ 18 F]FBCGly were observed. We have developed a radiosynthesis of a novel fluorine-18 labeled bile acid derivative, [ 18 F]FBCGly, and shown by PET/MR that [ 18 F]FBCGly undergoes continuous EHC in rats without metabolizing. This novel tracer may prove useful in PET studies on the effect of drugs or diseases on the EHC of conjugated bile acids. Copyright © 2018 Elsevier Inc. All rights reserved.

Down-regulation of adipose tissue lipoprotein lipase during fasting requires that a gene, separate from the lipase gene, is switched on.

PubMed

Bergö, Martin; Wu, Gengshu; Ruge, Toralph; Olivecrona, Thomas

2002-04-05

During short term fasting, lipoprotein lipase (LPL) activity in rat adipose tissue is rapidly down-regulated. This down-regulation occurs on a posttranslational level; it is not accompanied by changes in LPL mRNA or protein levels. The LPL activity can be restored within 4 h by refeeding. Previously, we showed that during fasting there is a shift in the distribution of lipase protein toward an inactive form with low heparin affinity. To study the nature of the regulatory mechanism, we determined the in vivo turnover of LPL activity, protein mass, and mRNA in rat adipose tissue. When protein synthesis was inhibited with cycloheximide, LPL activity and protein mass decreased rapidly and in parallel with half-lives of around 2 h, and the effect of refeeding was blocked. This indicates that maintaining high levels of LPL activity requires continuous synthesis of new enzyme protein. When transcription was inhibited by actinomycin, LPL mRNA decreased with half-lives of 13.3 and 16.8 h in the fed and fasted states, respectively, demonstrating slow turnover of the LPL transcript. Surprisingly, when actinomycin was given to fed rats, LPL activity was not down-regulated during fasting, indicating that actinomycin interferes with the transcription of a gene that blocks the activation of newly synthesized LPL protein. When actinomycin was given to fasted rats, LPL activity increased 4-fold within 6 h, even in the absence of refeeding. The same effect was seen with alpha-amanitin, another inhibitor of transcription. The response to actinomycin was much less pronounced in aging rats, which are obese and insulin-resistant. These data suggest a default state where LPL protein is synthesized on a relatively stable mRNA and is processed into its active form. During fasting, a gene is switched on whose product prevents the enzyme from becoming active even though synthesis of LPL protein continues unabated.

Iridium abundance measurements across bio-event horizons in the geological record

NASA Technical Reports Server (NTRS)

Orth, C. J.; Attrep, M., Jr.

1988-01-01

Geochemical studies have been performed on thousands of rock samples collected across bio-event horizons in the fossil record using INAA for about 40 common and trace elements and radiochemical isolation procedures for Os, Ir, Pt, and Au on selected samples. These studies were begun soon after the Alvarez team announced their discovery of the Cretaceous-Tertiary (K-T) Ir anomaly in marine rock sequences in Europe. With their encouragement the Authors searched for the anomaly in nearby continental (freshwater coal swamp) deposits. In collaboration with scientists from the U.S.G.S. in Denver, the anomaly was located and it was observed that a floral crisis occurred at the same stratigraphic position as the Ir spike. Further work in the Raton Basin has turned up numerous well-preserved K-T boundary sections. Although the Authors have continued to study the K-T boundary and provide geochemical measurements for other groups trying to precisely locate it, the primary effort was turned to examining the other bio-events in the Phanerozoic, especially to those that are older than the terminal Cretaceous. A list of horizons that were examined in collaboration with paleontologists and geologists is given. Results are also given and discussed.

The K{sub a}-band 10-kW continuous wave gyrotron with wide-band fast frequency sweep

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

Glyavin, M.; Luchinin, A.; Morozkin, M.

2012-07-15

The dual-frequency gyrotron with fast 2% frequency sweep at about 28 GHz is designed to power an electron cyclotron resonance ion source (ECRIS). Operation with an output power of up to 10 kW in CW mode and efficiency of 20% was demonstrated at both frequencies. Frequency manipulation has a characteristic time of about 1 ms and is based on magnetic field variation with an additional low-power coil. Fast frequency sweep will supposedly increase the ion current and the average ion charge of ECRIS. The possibility of 100% power modulation is demonstrated using the same control method.

The Use of Continuous Wavelet Transform Based on the Fast Fourier Transform in the Analysis of Multi-channel Electrogastrography Recordings.

PubMed

Komorowski, Dariusz; Pietraszek, Stanislaw

2016-01-01

This paper presents the analysis of multi-channel electrogastrographic (EGG) signals using the continuous wavelet transform based on the fast Fourier transform (CWTFT). The EGG analysis was based on the determination of the several signal parameters such as dominant frequency (DF), dominant power (DP) and index of normogastria (NI). The use of continuous wavelet transform (CWT) allows for better visible localization of the frequency components in the analyzed signals, than commonly used short-time Fourier transform (STFT). Such an analysis is possible by means of a variable width window, which corresponds to the scale time of observation (analysis). Wavelet analysis allows using long time windows when we need more precise low-frequency information, and shorter when we need high frequency information. Since the classic CWT transform requires considerable computing power and time, especially while applying it to the analysis of long signals, the authors used the CWT analysis based on the fast Fourier transform (FFT). The CWT was obtained using properties of the circular convolution to improve the speed of calculation. This method allows to obtain results for relatively long records of EGG in a fairly short time, much faster than using the classical methods based on running spectrum analysis (RSA). In this study authors indicate the possibility of a parametric analysis of EGG signals using continuous wavelet transform which is the completely new solution. The results obtained with the described method are shown in the example of an analysis of four-channel EGG recordings, performed for a non-caloric meal.

Development of an Intervention Programme to Encourage High School Students to Stay in School for Lunch Instead of Eating at Nearby Fast-Food Restaurants

ERIC Educational Resources Information Center

Beaulieu, Dominique; Godin, Gaston

2012-01-01

Many schools have recently adopted food policies and replaced unhealthy products by healthy foods. Consequently, adolescents are more likely to consume a healthy meal if they stay in school for lunch to eat a meal either prepared at home or purchased in school cafeterias. However, many continue to eat in nearby fast-food restaurants. The present…

Intermittent feeding in a migratory omnivore: Digestion and body composition of American Black Duck during autumn

USGS Publications Warehouse

Barboza, P.S.; Jorde, Dennis G.

2001-01-01

Birds fast intermittently during weather disturbances and migration. We tested responses of black duck to lost feeding days during autumn mass gain. Nine adult males were fed a pelleted diet (1.5% fat, 15.8% protein, and 18.3% neutral detergent fiber) and caged indoors during September and October (12 h light; 17? -24? C) to measure balances over 14 d when fed ad lib. each day and fasted intermittently for 2 d wk-1 (short fast) or 4 d wk-1 (long fast). Body mass (1,081 g), body water content, and metabolizable intakes of energy and protein were maintained as daily intakes of dry matter increased to 1.65 (short fast) and 2.35 (long fast) times the unfasted level. Intermittent feeding reduced metabolizability of dry matter, energy, protein, and acid detergent fiber. Concentrations of Mn provided similar estimates of metabolizability to direct measures in unfasted birds but underestimated measures of birds on long fasts. Fasting regimes continued outdoors for 9 wk when temperatures declined to -9? C. Birds on short fasts were heavier (1,373 vs. 1,241 g) and fatter (159 vs. 58 g) than those on long fasts, while body water (894 g) and protein (316 g) were similar between groups after 5 wk. Birds on long fasts subsequently gained mass when fed daily, but those on short fasts lost mass when fed each day. Omnivorous waterfowl combine ingestive and digestive flexibility with plasticity of body lipid to contend with uncertain food availability.

History of fast reactor fuel development

NASA Astrophysics Data System (ADS)

Kittel, J. H.; Frost, B. R. T.; Mustelier, J. P.; Bagley, K. Q.; Crittenden, G. C.; Van Dievoet, J.

1993-09-01

The first fast breeder reactors, constructed in the 1945-1960 time period, used metallic fuels composed of uranium, plutonium, or their alloys. They were chosen because most existing reactor operating experience had been obtained on metallic fuels and because they provided the highest breeding ratios. Difficulties in obtaining adequate dimensional stability in metallic fuel elements under conditions of high fuel burnup led in the 1960s to the virtual worldwide choice of ceramic fuels. Although ceramic fuels provide lower breeding performance, this objective is no longer an important consideration in most national programs. Mixed uranium and plutonium dioxide became the ceramic fuel that has received the widest use. The more advanced ceramic fuels, mixed uranium and plutonium carbides and nitrides, continue under development. More recently, metal fuel elements of improved design have joined ceramic fuels in achieving goal burnups of 15 to 20 percent. Low-swelling fuel cladding alloys have also been continuously developed to deal with the unexpected problem of void formation in stainless steels subjected to fast neutron irradiation, a phenomenon first observed in the 1960s.

Airline business continuity and IT disaster recovery sites.

PubMed

Haji, Jassim

2016-01-01

Business continuity is defined as the capability of the organisation to continue delivery of products or services at acceptable predefined levels following a disruptive incident. Business continuity is fast evolving to become a critical and strategic decision for any organisation. Transportation in general, and airlines in particular, is a unique sector with a specialised set of requirements, challenges and opportunities. Business continuity in the airline sector is a concept that is generally overlooked by the airline managements. This paper reviews different risks related to airline processes and will also propose solutions to these risks based on experiences and good industry practices.

Overuse Injury Assessment Model

DTIC Science & Technology

2007-08-01

and reduce injuries is a continual challenge. Military researchers face challenges to develop better equipment, improve training regimens, and...performed and calculate biomechanical metrics for each activity. Hardware Challenges • Sampling the sensors sufficiently fast • Having adequate bandwidth...second is that the injury rate increases rapidly initially and, third, that the injury rate continues to climb as the cumulative distance increases

A qualitative study into the impact of fasting within a large tertiary hospital in Australia--the patients' perspective.

PubMed

Carey, Sharon K; Conchin, Simone; Bloomfield-Stone, Susan

2015-07-01

This qualitative study aims to explore the physical and emotional impact of fasting from the patients' perspective. Fasting patients in hospital is common practice and generally viewed as necessary for symptom management or for safety of healthcare provision. Negative impacts of repeated or prolonged fasting on nutritional status have been well researched, but little is documented as to how fasting impacts an individual patient's psyche. Qualitative descriptive design within a tertiary hospital in Sydney, Australia. Twelve patients having had prolonged periods of continuous or intermittent fasting were invited to participate in a semi-structured interview between January-September 2012. Questions for interview explored each patient's experience of fasting, including physical and emotional impacts, interpretation of communication regarding fasting and the process of recommencing on fluids or foods. An inductive thematic analysis approach was used. Analyses showed six main themes: physical impacts; emotional impacts; food as structure; nil by mouth as jargon; fear of food re-introduction; and dissatisfaction regarding unnecessary fasting. Overwhelmingly, thirst was reported as the worst physical effect of fasting. In the first few days of fasting, patients became emotionally fixated on food. This quickly dissipated leading to a lack of appetite and fear of starting to eat again. Discomfort experienced by patients coupled with lack of appetite resulting from prolonged fasting and difficulty with food re-introduction strengthens the argument for reducing fasting times in hospital. When patients are fasted, proper hydration and establishing alternate routes of medication administration should be a priority. It is well recognised that fasting for prolonged periods is detrimental to health outcomes, but this study also shows the distress that fasting can cause. Inadequate hospital systems and out-dated practices need to be replaced with evidence-based, patient-centred governance, addressing the physical, emotional and psychosocial impact of fasting. © 2015 John Wiley & Sons Ltd.

On generic obstructions to recovering correct statistics from climate simulations: Homogenization for deterministic maps and multiplicative noise

NASA Astrophysics Data System (ADS)

Gottwald, Georg; Melbourne, Ian

2013-04-01

Whereas diffusion limits of stochastic multi-scale systems have a long and successful history, the case of constructing stochastic parametrizations of chaotic deterministic systems has been much less studied. We present rigorous results of convergence of a chaotic slow-fast system to a stochastic differential equation with multiplicative noise. Furthermore we present rigorous results for chaotic slow-fast maps, occurring as numerical discretizations of continuous time systems. This raises the issue of how to interpret certain stochastic integrals; surprisingly the resulting integrals of the stochastic limit system are generically neither of Stratonovich nor of Ito type in the case of maps. It is shown that the limit system of a numerical discretisation is different to the associated continuous time system. This has important consequences when interpreting the statistics of long time simulations of multi-scale systems - they may be very different to the one of the original continuous time system which we set out to study.

Development and application of a continuous fast microwave pyrolysis system for sewage sludge utilization.

PubMed

Zhou, Junwen; Liu, Shiyu; Zhou, Nan; Fan, Liangliang; Zhang, Yaning; Peng, Peng; Anderson, Erik; Ding, Kuan; Wang, Yunpu; Liu, Yuhuan; Chen, Paul; Ruan, Roger

2018-05-01

A continuous fast microwave-assisted pyrolysis system was designed, fabricated, and tested with sewage sludge. The system is equipped with continuous biomass feeding, mixing of biomass and microwave absorbent, and separated catalyst upgrading. The effect of the sludge pyrolysis temperature (450, 500, 550, and 600 °C) on the products yield, distribution and potentially energy recovery were investigated. The physical, chemical, and energetic properties of the raw sewage sludge and bio-oil, char and gas products obtained were analyzed using elemental analyzer, GC-MS, Micro-GC, SEM and ICP-OES. While the maximum bio-oil yield of 41.39 wt% was obtained at pyrolysis temperature of 550 °C, the optimal pyrolysis temperature for maximum overall energy recovery was 500 °C. The absence of carrier gas in the process may be responsible for the high HHV of gas products. This work could provide technical support for microwave-assisted system scale-up and sewage sludge utilization. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of extended regimens of the contraceptive vaginal ring on carbohydrate metabolism.

PubMed

Guazzelli, Cristina A F; Barreiros, Fernando A; Torloni, Maria R; Barbieri, Marcia

2012-03-01

There are few publications on the metabolic effects of extended regimens of the contraceptive vaginal ring. The aim of this study was to assess changes in fasting plasma glucose levels and insulin concentration of women using the contraceptive vaginal ring continuously over a 1-year period. This prospective cohort enrolled 75 women (ages 18-37 years) who used a contraceptive vaginal ring releasing 120 mcg of etonogestrel and 15 mcg of ethinyl estradiol daily continuously for 84 days, followed by a 7-day ring-free interval, during 1 year. Fasting glucose and insulin levels were measured, and homeostatic model assessment was calculated at baseline and every 3 months during the 1-year study period. The repeated-measures analysis of variance test was used to analyze differences in the results of these exams over time. None of the 75 participants had results outside the normal range in any of the assessments. There were no pregnancies during the 1-year period, and a total of 62 participants completed the study. There were no significant changes in mean fasting glucose levels (79.3 and 78.9 mg/dL at baseline and after 12 months, respectively), mean fasting insulin concentration (9.6 and 10.1 μU/mL) or mean homeostatic model assessment results (1.88% and 1.97%). Fasting plasma glucose concentration, insulin levels and homeostatic model assessment values of women using the vaginal ring on an extended regimen did not change significantly over a 1-year period. Copyright © 2012 Elsevier Inc. All rights reserved.

Effects of fasting, temperature, and photoperiod on preproghrelin mRNA expression in Chinese perch.

PubMed

Song, Yi; Zhao, Cheng; Liang, Xu-Fang; He, Shan; Tian, Changxu; Cheng, Xiaoyan; Yuan, Xiaochen; Lv, Liyuan; Guo, Wenjie; Xue, Min; Tao, Ya-Xiong

2017-06-01

Preproghrelin, a gut/brain peptide, plays an important role in the regulation of food intake and energy homeostasis in teleost and mammals. In the present study, we obtained the full-length preproghrelin cDNA in Chinese perch. The preproghrelin messenger RNA (mRNA) tissue expression showed that level was much higher in stomach and pituitary than in other tissues. The fasting study showed, after gastric emptying (3-6 h), short-term fasting (6-12 h) increased preproghrelin expression in the stomach. While in the pituitary, fasting reduced preproghrelin expression at 1, 3, 12, and 48 h, presenting state fluctuation of self-adjustment. The temperature study showed that the mRNA expression of preproghrelin was the highest in the brain at 26 °C and highest in the stomach at 32 °C, respectively, with different optimum temperature in these two tissues, reflecting spatiotemporal differences of regulation by central nervous system and peripheral organs. The photoperiod study showed that normal light (11 h of lightness and 13 h of darkness) led to highest preproghrelin expression, both in the brain and in the stomach, than continuous light or continuous dark, proving food intake is adapted to natural photoperiod or normal light in this study. These results all indicated that tissue-specific preproghrelin expression of Chinese perch could be significantly affected by environmental factors. Short-term fasting of 6 h after gastric emptying, 26 °C, and normal light led to higher preproghrelin expression, which indicated potential appetite increase in Chinese perch.

Controlling slow and fast light and dynamic pulse-splitting with tunable optical gain in a whispering-gallery-mode microcavity

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

Asano, M.; Ikuta, R.; Imoto, N.

We report controllable manipulation of slow and fast light in a whispering-gallery-mode microtoroid resonator fabricated from Erbium (Er{sup 3+}) doped silica. We observe continuous transition of the coupling between the fiber-taper waveguide and the microresonator from undercoupling to critical coupling and then to overcoupling regimes by increasing the pump power even though the spatial distance between the resonator and the waveguide was kept fixed. This, in turn, enables switching from fast to slow light and vice versa just by increasing the optical gain. An enhancement of delay of two-fold over the passive silica resonator (no optical gain) was observed inmore » the slow light regime. Moreover, we show dynamic pulse splitting and its control in slow/fast light systems using optical gain.« less

Bio-oil production from palm fronds by fast pyrolysis process in fluidized bed reactor

NASA Astrophysics Data System (ADS)

Rinaldi, Nino; Simanungkalit, Sabar P.; Kiky Corneliasari, S.

2017-01-01

Fast pyrolysis process of palm fronds has been conducted in the fluidized bed reactor to yield bio-oil product (pyrolysis oil). The process employed sea sand as the heat transfer medium. The objective of this study is to design of the fluidized bed rector, to conduct fast pyrolysis process to product bio-oil from palm fronds, and to characterize the feed and bio-oil product. The fast pyrolysis process was conducted continuously with the feeding rate around 500 g/hr. It was found that the biomass conversion is about 35.5% to yield bio-oil, however this conversion is still minor. It is suggested due to the heating system inside the reactor was not enough to decompose the palm fronds as a feedstock. Moreover, the acids compounds ware mostly observed on the bio-oil product.

The enzymic preparation of (14)C-kaurene.

PubMed

Graebe, J E

1969-06-01

Endosperm from immature seeds of Cucurbita pepo L. converts 2-(14)C-DL-mevalonate to (14)C-(-)-kaurene with a yield of nearly 40% of the active isomer. Kaurene is the main product and the only diterpene hydrocarbon which is formed from mevalonate in the system and is therefore easily obtained radiochemically pure. The product was identified by thin-layer chromatography and recrystallization with authentic (-)-kaurene to constant specific radioactivity.

ANALYTICAL CHEMISTRY DIVISION ANNUAL PROGRESS REPORT FOR PERIOD ENDING DECEMBER 31, 1961

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

None

1962-02-01

Research and development progress is reported on analytlcal instrumentation, dlssolver-solution analyses, special research problems, reactor projects analyses, x-ray and spectrochemical analyses, mass spectrometry, optical and electron microscopy, radiochemical analyses, nuclear analyses, inorganic preparations, organic preparations, ionic analyses, infrared spectral studies, anodization of sector coils for the Analog II Cyclotron, quality control, process analyses, and the Thermal Breeder Reactor Projects Analytical Chemistry Laboratory. (M.C.G.)

Risk and Safety in Post-Soviet Russia

DTIC Science & Technology

2008-09-01

radiation exposure databases from Chernobyl , radioactive contamination from long-term operation of large radiochemical atomic plants, and the impact of...64 9.4 Single Irradiation of the Population 65 9.5 Chronic Irradiation of the Population and Personnel 66 9.6. Conclusions 67 10.0 Chernobyl ...Related Radiation Risk for the Public 76 10.1 Introduction 76 10.2 Radioactive Contamination of Russian Territories as a Result of the Chernobyl

Rapid Radiochemical Method for Isotopic Uranium in Building ...

EPA Pesticide Factsheets

Technical Fact Sheet Analysis Purpose: Qualitative analysis Technique: Alpha spectrometry Method Developed for: Uranium-234, uranium-235, and uranium-238 in concrete and brick samples Method Selected for: SAM lists this method for qualitative analysis of uranium-234, uranium-235, and uranium-238 in concrete or brick building materials. Summary of subject analytical method which will be posted to the SAM website to allow access to the method.

CPTAC Develops Fit-for-Purpose Multiplex Immuno-MRM Assay for Profiling the DNA Damage Response Pathway | Office of Cancer Clinical Proteomics Research

Cancer.gov

Ionizing radiation (IR) is a commonly employed cancer treatment that kills cancer cells by damaging their DNA. While the DNA damage response (DDR) pathway may be key to determining tumor responses, radiochemical damage due to IR can target the patients’ healthy dividing cells, leading to the formation of secondary hematologic and solid tumors after DNA-damaging therapy.

SCALE TSUNAMI Analysis of Critical Experiments for Validation of 233U Systems

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

Mueller, Don; Rearden, Bradley T

2009-01-01

Oak Ridge National Laboratory (ORNL) staff used the SCALE TSUNAMI tools to provide a demonstration evaluation of critical experiments considered for use in validation of current and anticipated operations involving {sup 233}U at the Radiochemical Development Facility (RDF). This work was reported in ORNL/TM-2008/196 issued in January 2009. This paper presents the analysis of two representative safety analysis models provided by RDF staff.

Overview of the application of nanosecond electron beams for radiochemical sterilization

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

Kotov, Y.A.; Sokovnin, S.Y.

Problems concerning the use of nanosecond electron beams for sterilization of hermetically packed objects, and powdered or granulated materials, are discussed. The advantages and disadvantages of this type of radiation sterilization are demonstrated. The results are of interest to researchers who study the mechanism by which nanosecond electron beams act on microorganisms. It is worth considering repetitively pulsed electron accelerators as highly promising systems for use in commercial sterilization applications. Technologies and setups for the radiochemical sterilization (RCS) of medical glassware for blood products, beer bottles, bone meal used in food industry, medical instruments (surgical needles, systems for human kidneys),more » and of the external packaging for some biological materials used in ophthalmology are discussed. Such applications have been developed based on the use of the URT-0.2 and URT-0.5 repetitively nanosecond-pulsed electron accelerators. The observed sterilization of areas shaded from line-of-site irradiation and of the bottoms of, for example, glassware cannot be attributed to radiation sterilization alone, since the glass thickness was much larger than the range of electrons. Therefore, it can be conjectured that the demonstrated sterilization effect is due both to the electron beam and to the ozone and chemical radicals produced by the beam. Thus, one may introduce the notion of RCS.« less

[18F]FEPPA a TSPO Radioligand: Optimized Radiosynthesis and Evaluation as a PET Radiotracer for Brain Inflammation in a Peripheral LPS-Injected Mouse Model.

PubMed

Vignal, Nicolas; Cisternino, Salvatore; Rizzo-Padoin, Nathalie; San, Carine; Hontonnou, Fortune; Gelé, Thibaut; Declèves, Xavier; Sarda-Mantel, Laure; Hosten, Benoît

2018-06-07

[ 18 F]FEPPA is a specific ligand for the translocator protein of 18 kDa (TSPO) used as a positron emission tomography (PET) biomarker for glial activation and neuroinflammation. [ 18 F]FEPPA radiosynthesis was optimized to assess in a mouse model the cerebral inflammation induced by an intraperitoneal injection of Salmonella enterica serovar Typhimurium lipopolysaccharides (LPS; 5 mg/kg) 24 h before PET imaging. [ 18 F]FEPPA was synthesized by nucleophilic substitution (90 °C, 10 min) with tosylated precursor, followed by improved semi-preparative HPLC purification (retention time 14 min). [ 18 F]FEPPA radiosynthesis were carried out in 55 min (from EOB). The non-decay corrected radiochemical yield were 34 ± 2% ( n = 17), and the radiochemical purity greater than 99%, with a molar activity of 198 ± 125 GBq/µmol at the end of synthesis. Western blot analysis demonstrated a 2.2-fold increase in TSPO brain expression in the LPS treated mice compared to controls. This was consistent with the significant increase of [ 18 F]FEPPA brain total volume of distribution ( V T ) estimated with pharmacokinetic modelling. In conclusion, [ 18 F]FEPPA radiosynthesis was implemented with high yields. The new purification/formulation with only class 3 solvents is more suitable for in vivo studies.

Synthesis of carbon-11-labeled imidazopyridine- and purine-thioacetamide derivatives as new potential PET tracers for imaging of nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1).

PubMed

Gao, Mingzhang; Wang, Min; Zheng, Qi-Huang

2016-03-01

The target tracer carbon-11-labeled imidazopyridine- and purine-thioacetamide derivatives, N-(3-[(11)C]methoxy-4-methoxyphenyl)-2-((5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)thio)acetamide (3-[(11)C]4a) and N-(4-[(11)C]methoxy-3-methoxyphenyl)-2-((5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)thio)acetamide (4-[(11)C]4a); 2-((6-amino-9H-purin-8-yl)thio)-N-(3-[(11)C]methoxy-4-methoxyphenyl)acetamide (3-[(11)C]8a) and 2-((6-amino-9H-purin-8-yl)thio)-N-(4-[(11)C]methoxy-3-methoxyphenyl)acetamide (4-[(11)C]8a), were prepared by O-[(11)C]methylation of their corresponding precursors with [(11)C]CH3OTf under basic condition (2N NaOH) and isolated by a simplified solid-phase extraction (SPE) method in 50-60% radiochemical yields based on [(11)C]CO2 and decay corrected to end of bombardment (EOB). The overall synthesis time from EOB was 23min, the radiochemical purity was >99%, and the specific activity at end of synthesis (EOS) was 185-555GBq/μmol. Copyright © 2016 Elsevier Ltd. All rights reserved.

ALPHA SPECTROMETRIC EVALUATION OF SRM-995 AS A POTENTIAL URANIUM/THORIUM DOUBLE TRACER SYSTEM FOR AGE-DATING URANIUM MATERIALS

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

Beals, D.

2011-12-06

Uranium-233 (t{sub 1/2} {approx} 1.59E5 years) is an artificial, fissile isotope of uranium that has significant importance in nuclear forensics. The isotope provides a unique signature in determining the origin and provenance of uranium-bearing materials and is valuable as a mass spectrometric tracer. Alpha spectrometry was employed in the critical evaluation of a {sup 233}U standard reference material (SRM-995) as a dual tracer system based on the in-growth of {sup 229}Th (t{sub 1/2} {approx} 7.34E3 years) for {approx}35 years following radiochemical purification. Preliminary investigations focused on the isotopic analysis of standards and unmodified fractions of SRM-995; all samples were separatedmore » and purified using a multi-column anion-exchange scheme. The {sup 229}Th/{sup 233}U atom ratio for SRM-995 was found to be 1.598E-4 ({+-} 4.50%) using recovery-corrected radiochemical methods. Using the Bateman equations and relevant half-lives, this ratio reflects a material that was purified {approx} 36.8 years prior to this analysis. The calculated age is discussed in contrast with both the date of certification and the recorded date of last purification.« less

Structural analysis of an HLA-B27 functional variant, B27d detected in American blacks

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

Rojo, S.; Aparicio, P.; Hansen, J.A.

1987-11-15

The structure of a new functional variant B27d has been established by comparative peptide mapping and radiochemical sequencing. This analysis complete the structural characterization of the six know histocompatibility leukocyte antigen (HLA)-B27 subtypes. The only detected amino acid change between the main HLA-B27.1 subtype and B27d is that of Try/sub 59/ to His/sub 59/. Position 59 has not been previously found to vary among class I HLA or H-2 antigens. Such substitution accounts for the reported isoelectric focusing pattern of this variant. HLA-B27d is the only B27 variant found to differ from other subtypes by a single amino acid replacement.more » The nature of the change is compatible with its origin by a point mutation from HLB-B27.1. Because B27d was found only American blacks and in no other ethnic groups, it is suggested that this variant originated as a result of a mutation of the B27.1 gene that occurred within the black population. Structural analysis of B27d was done by comparative mapping. Radiochemical sequencing was carried out with /sup 14/C-labeled and /sup 3/H-labeled amino acids.« less

A new method for the radiochemical purity measurement of ¹¹¹In-pentetreotide.

PubMed

Salgado-Garcia, Carlos; Montoza-Aguado, Manuel; Luna-Alcaide, Ana B; Segovia-Gonzalez, Maria M; de Mora, Elena Sanchez; Lopez-Martin, Juana; Ramos-Font, Carlos; Jimenez-Heffernan, Amelia

2011-12-01

The recommended method for the measurement of radiochemical purity (RCP) of ¹¹¹In-labelled pentetreotide is thin-layer chromatography with a silica gel as the stationary phase and a 0.1 N sodium citrate solution (pH 5) as the mobile phase. According to the supplier's instructions, the mobile phase must be prepared before the test is carried out, and the recommended stationary phase is off-market. We propose a new method for RCP measurement in which the mobile phase is acid citrate dextrose, solution A, which does not need to be prepared beforehand, and thin-layer chromatography is performed with a silica gel-impregnated glass fibre sheet as the stationary phase. We used both methods to measure the percentages of radiopharmaceutical and impurities. The range of RCP values obtained was 98.0-99.9% (mean=99.3%) by the standard method and 98.1-99.9% (mean=99.2%) by the new method. We observed no differences between the RCP values of both methods (P=0.070). The proposed method is suitable for RCP testing because it yields results that are in good agreement with those of the standard method and because it is easier to perform as the mobile-phase solution need not be prepared in advance.

Radiochemical Procedures Used at Iaea-Ilmr Monaco for Measuring Artificial Radionuclides Resulting from the Chernobyl Accident

NASA Astrophysics Data System (ADS)

Ballestra, S.; Gastaud, J.; Lopez, J. J.

The Chernobyl accident which occurred on 26 April 1986 resulted in relatively high levels of radioactive fallout over the major part of Europe. Air filter and precipitation samples enabled us to follow the contamination from the accident. In addition contamination was also monitored in selected environmental samples such as seaweeds, sea water, sediment, soil, suspended matter and biological material from the Mediterranean. All samples were counted on Ge(Li) or Ge(HP) detectors to determine the type and quantity of gamma emitting radionuclides and plutonium, americium and curium isotopes were separated and measured using radiochemical techniques and alpha counting. Increased atmospheric radioactivity from the Chernobyl accident was first detected by observing increased activity levels on air filters taken on April 30, 1986, with maximum activities occurring during 1-3 May. Most of the radionuclides initially measured were short-lived fission products. Cs-137 was one of the predominant isotope in the fallout debris and its deposition at Monaco due to Chernobyl was estimated to be around 1400 Bq m-2, which represents 25-40% of the integrated fallout at this latitude. The deposition of Pu-239+240 was much smaller and was estimated to be around 10 mBq m-2 or only 0.1% of the total deposition from nuclear weapon testing.

Radiosynthesis and radiopharmacological evaluation of [N-methyl-11C]Org 34850 as a glucocorticoid receptor (GR)-binding radiotracer.

PubMed

Wuest, Frank; Kniess, Torsten; Henry, Brian; Peeters, Bernardus W M M; Wiegerinck, Peter H G; Pietzsch, Jens; Bergmann, Ralf

2009-02-01

The radiosynthesis of [N-methyl-(11)C]Org 34850 as a potential brain glucocorticoid receptor (GR)-binding radiotracer is described. The radiosynthesis was accomplished via N-methylation of the corresponding desmethyl precursor with [(11)C]methyl triflate in a remotely controlled synthesis module to give the desired compound in a radiochemical yield of 23+/-5% (decay-corrected, based upon [(11)C]CO(2)) at a specific activity of 47+/-12 GBq/micromol (n=15) at the end-of-synthesis (EOS). The radiochemical purity after semi-preparative HPLC purification exceeded 95%. The total synthesis time was 35-40 min after end-of-bombardment (EOB). The radiotracer is rapidly metabolized in rat plasma leading to the formation of two more hydrophilic metabolites as the major metabolites. Radiopharmacological evaluation involving biodistribution and small animal PET imaging in normal Wistar rats showed that the compound [N-methyl-(11)C]Org 34850 is not able to sufficiently penetrate the blood-brain barrier. Therefore, compound [N-methyl-(11)C]Org 34850 seems not to be a suitable PET radiotracer for imaging rat brain GRs. However, involvement of Pgp or species differences requires further clarification to establish whether the radiotracer [N-methyl-(11)C]Org 34850 may still represent a suitable candidate for imaging GRs in humans.

Synthesis, radiolabeling, and biological evaluation of ( R)- and ( S)-2-amino-5-[ 18F]fluoro-2-methylpentanoic acid (( R)-, ( S)-[ 18F]FAMPe) as potential positron emission tomography tracers for brain tumors

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

Bouhlel, Ahlem; Zhou, Dong; Li, Aixiao

In this paper, a novel 18F-labeled α,α-disubstituted amino acid-based tracer, 2-amino-5-[ 18F]fluoro-2-methylpentanoic acid ([ 18F]FAMPe), has been developed for brain tumor imaging with a longer alkyl side chain than previously reported compounds to increase brain availability via system L amino acid transport. Both enantiomers of [ 18F]FAMPe were obtained in good radiochemical yield (24–52% n = 8) and high radiochemical purity (>99%). In vitro uptake assays in mouse DBT gliomas cells revealed that ( S)-[ 18F]FAMPe enters cells partly via sodium-independent system L transporters and also via other nonsystem A transport systems including transporters that recognize glutamine. Biodistribution and smallmore » animal PET/CT studies in the mouse DBT model of glioblastoma showed that both ( R)- and ( S)-[ 18F]FAMPe have good tumor imaging properties with the ( S)-enantiomer providing higher tumor uptake and tumor to brain ratios. Finally, comparison of the SUVs showed that ( S)-[ 18F]FAMPe had higher tumor to brain ratios compared to ( S)-[ 18F]FET, a well-established system L substrate.« less

Rapid synthesis of maleimide functionalized fluorine-18 labeled prosthetic group using "radio-fluorination on the Sep-Pak" method.

PubMed

Basuli, Falguni; Zhang, Xiang; Jagoda, Elaine M; Choyke, Peter L; Swenson, Rolf E

2018-06-30

Following our recently published fluorine-18 labeling method, "Radio-fluorination on the Sep-Pak", we have successfully synthesized 6-[ 18 F]fluoronicotinaldehyde by passing a solution (1:4 acetonitrile: t-butanol) of its quaternary ammonium salt precursor, 6-(N,N,N-trimethylamino)nicotinaldehyde trifluoromethanesulfonate (2), through a fluorine-18 containing anion exchange cartridge (PS-HCO 3 ). Over 80% radiochemical conversion was observed using 10 mg of precursor within 1 minute. The [ 18 F]fluoronicotinaldehyde ([ 18 F]5) was then conjugated with 1-(6-(aminooxy)hexyl)-1H-pyrrole-2,5-dione to prepare the fluorine-18 labeled maleimide functionalized prosthetic group, 6-[ 18 F]fluoronicotinaldehyde O-(6-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)hexyl) oxime, 6-[ 18 F]FPyMHO ([ 18 F]6). The current Sep-Pak method not only improves the overall radiochemical yield (50 ± 9%, decay-corrected, n = 9) but also significantly reduces the synthesis time (from 60-90 minutes to 30 minutes) when compared with literature methods for the synthesis of similar prosthetic groups. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Synthesis, radiolabeling, and biological evaluation of ( R)- and ( S)-2-amino-5-[ 18F]fluoro-2-methylpentanoic acid (( R)-, ( S)-[ 18F]FAMPe) as potential positron emission tomography tracers for brain tumors

DOE PAGES

Bouhlel, Ahlem; Zhou, Dong; Li, Aixiao; ...

2015-04-06

In this paper, a novel 18F-labeled α,α-disubstituted amino acid-based tracer, 2-amino-5-[ 18F]fluoro-2-methylpentanoic acid ([ 18F]FAMPe), has been developed for brain tumor imaging with a longer alkyl side chain than previously reported compounds to increase brain availability via system L amino acid transport. Both enantiomers of [ 18F]FAMPe were obtained in good radiochemical yield (24–52% n = 8) and high radiochemical purity (>99%). In vitro uptake assays in mouse DBT gliomas cells revealed that ( S)-[ 18F]FAMPe enters cells partly via sodium-independent system L transporters and also via other nonsystem A transport systems including transporters that recognize glutamine. Biodistribution and smallmore » animal PET/CT studies in the mouse DBT model of glioblastoma showed that both ( R)- and ( S)-[ 18F]FAMPe have good tumor imaging properties with the ( S)-enantiomer providing higher tumor uptake and tumor to brain ratios. Finally, comparison of the SUVs showed that ( S)-[ 18F]FAMPe had higher tumor to brain ratios compared to ( S)-[ 18F]FET, a well-established system L substrate.« less

Fast cadence planet-searches with the all-sky, gigapixel-scale Evryscope

NASA Astrophysics Data System (ADS)

Ratzloff, Jeff; Law, Nicholas

2018-01-01

The Evryscope is a 24-camera robotic telescope that continuously images 8,000 square degrees in 2-minute exposures, that has been collecting data continuously since deployment to CTIO in mid-2015. The telescope provides the fast cadence observations necessary for detecting minute to tens-of-minute time-scale exoplanet transits, which would occur around small, compact host stars including White Dwarfs and Hot Subdwarfs. We are conducting target surveys for each of these types of stars searching for potential planet transit signals. Our surveys will be the largest performed to date with several thousand targets in each group and years of observations, and the only surveys with minute-scale cadence. We present the status of the surveys, our estimated detection ability, interesting candidates, and preliminary results.

Integration of Fire Control, Flight Control and Propulsion Control Systems.

DTIC Science & Technology

1983-08-01

process of preparation to a degree imocmpatible with fast moving technology. Undoubtedly something can be done to see that US authors produce papers...PDU provide a true "Up Front" system controller. Fast selection of Air to Air Mode is provided by 2 pushbuttons on the throttle. Pushing one or both...nature of the load snd its effect on the generation system. This calculation will include Load Power, Reactance, Nature - continuous or intermittent

Ultrasound sounding in air by fast-moving receiver

NASA Astrophysics Data System (ADS)

Sukhanov, D.; Erzakova, N.

2018-05-01

A method of ultrasound imaging in the air for a fast receiver. The case, when the speed of movement of the receiver can not be neglected with respect to the speed of sound. In this case, the Doppler effect is significant, making it difficult for matched filtering of the backscattered signal. The proposed method does not use a continuous repetitive noise-sounding signal. generalized approach applies spatial matched filtering in the time domain to recover the ultrasonic tomographic images.

Resolving the Nurse Crisis in San Antonio

DTIC Science & Technology

2007-04-01

health care services will rise dramatically. The reality is that the supply of nurses is not growing as fast as the demand for nurses is. This growing...shortage of nurses threatens the ability of hospitals and other health care providers to continue providing the health care services we all depend on...over the next decade, demand for health care services will rise dramatically. The reality is that the supply of nurses is not growing as fast as the

Fast two-dimensional grid and transmission X-ray microscopy scanning methods for visualizing and characterizing protein crystals

PubMed Central

Wojdyla, Justyna Aleksandra; Panepucci, Ezequiel; Martiel, Isabelle; Ebner, Simon; Huang, Chia-Ying; Caffrey, Martin; Bunk, Oliver; Wang, Meitian

2016-01-01

A fast continuous grid scan protocol has been incorporated into the Swiss Light Source (SLS) data acquisition and analysis software suite on the macromolecular crystallography (MX) beamlines. Its combination with fast readout single-photon counting hybrid pixel array detectors (PILATUS and EIGER) allows for diffraction-based identification of crystal diffraction hotspots and the location and centering of membrane protein microcrystals in the lipid cubic phase (LCP) in in meso in situ serial crystallography plates and silicon nitride supports. Diffraction-based continuous grid scans with both still and oscillation images are supported. Examples that include a grid scan of a large (50 nl) LCP bolus and analysis of the resulting diffraction images are presented. Scanning transmission X-ray microscopy (STXM) complements and benefits from fast grid scanning. STXM has been demonstrated at the SLS beamline X06SA for near-zero-dose detection of protein crystals mounted on different types of sample supports at room and cryogenic temperatures. Flash-cooled crystals in nylon loops were successfully identified in differential and integrated phase images. Crystals of just 10 µm thickness were visible in integrated phase images using data collected with the EIGER detector. STXM offers a truly low-dose method for locating crystals on solid supports prior to diffraction data collection at both synchrotron microfocusing and free-electron laser X-ray facilities. PMID:27275141

Benchmark of multi-phase method for the computation of fast ion distributions in a tokamak plasma in the presence of low-amplitude resonant MHD activity

NASA Astrophysics Data System (ADS)

Bierwage, A.; Todo, Y.

2017-11-01

The transport of fast ions in a beam-driven JT-60U tokamak plasma subject to resonant magnetohydrodynamic (MHD) mode activity is simulated using the so-called multi-phase method, where 4 ms intervals of classical Monte-Carlo simulations (without MHD) are interlaced with 1 ms intervals of hybrid simulations (with MHD). The multi-phase simulation results are compared to results obtained with continuous hybrid simulations, which were recently validated against experimental data (Bierwage et al., 2017). It is shown that the multi-phase method, in spite of causing significant overshoots in the MHD fluctuation amplitudes, accurately reproduces the frequencies and positions of the dominant resonant modes, as well as the spatial profile and velocity distribution of the fast ions, while consuming only a fraction of the computation time required by the continuous hybrid simulation. The present paper is limited to low-amplitude fluctuations consisting of a few long-wavelength modes that interact only weakly with each other. The success of this benchmark study paves the way for applying the multi-phase method to the simulation of Abrupt Large-amplitude Events (ALE), which were seen in the same JT-60U experiments but at larger time intervals. Possible implications for the construction of reduced models for fast ion transport are discussed.

Differences in perceptions and fast food eating behaviours between Indians living in high- and low-income neighbourhoods of Chandigarh, India.

PubMed

Aloia, Christopher Robert; Gasevic, Danijela; Yusuf, Salim; Teo, Koon; Chockalingam, Arun; Patro, Binod Kumar; Kumar, Rajesh; Lear, Scott Alexander

2013-01-07

Increased density of fast food restaurants is associated with increased prevalence of obesity in developed countries. However, less is known about this relationship in developing countries undergoing rapid urbanization and how differences in neighbourhood income affect the patronage of fast food outlets. The purpose of the study is to explore the differences in fast food preferences, perceptions, and patronage between Indians living in high- and low-income neighbourhoods. This cross-sectional study recruited 204 men and women (35 to 65 years in age) from high- and low-income neighbourhoods who completed a questionnaire on fast food consumption. The questionnaire asked participants to define fast food and to provide reasons for and frequency of visits to fast food restaurants. The differences were analyzed using Chi square and t-tests for categorical and continuous variables, respectively. Participants from a high-income neighbourhood were more likely to perceive Western -style fast food as fast food, while people from the low-income neighbourhood were more likely to identify food sold by street vendors as fast food (p <0.001). Furthermore, compared to participants from the high-income neighbourhood, people from the low-income neighbourhood were more likely to report buying food from street vendors while less likely to dine out at both fast food and non-fast food restaurants (p<0.001). Although the high-income neighbourhood group was more likely to report enjoying eating at fast food restaurants than their low-income neighbourhood counterparts, there were no significant differences in the reasons for visiting fast food restaurants (convenience, price, social enjoyment, and quality of meals) between the two groups. Both groups preferred home cooked over restaurant meals, and they recognized that home cooked food was healthier. Overall, consumption of fast food was low. People from a high-income neighbourhood dined out more frequently and were more likely to perceive Western-style food as fast food compared to their counterparts from the low-income neighbourhood.

Lipid Panel

MedlinePlus

... Time and International Normalized Ratio (PT/INR) PSEN1 Quantitative Immunoglobulins Red Blood Cell (RBC) Antibody Identification Red ... typically includes a fasting lipid panel. Beyond that, research continues into the usefulness of other non-traditional ...

Progress toward a unified kJ-machine CANDY

NASA Astrophysics Data System (ADS)

Kitagawa, Yoneyoshi; Mori, Yoshitaka; Komeda, Osamu; Hanayama, Ryohei; Ishii, Katsuhiro; Okihara, Shinichiro; Fujita, Kazuhisa; Nakayama, Suisei; Sekine, Takashi; Sato, Nakahiro; Kurita, Takashi; Kawashima, Toshiyuki; Watari, Takeshi; Kan, Hirofumi; Nakamura, Naoki; Kondo, Takuya; Fujine, Manabu; Azuma, Hirozumi; Motohiro, Tomoyoshi; Hioki, Tatsumi; Kakeno, Mitsutaka; Nishimura, Yasuhiko; Sunahara, Atsushi; Sentoku, Yasuhiko; Miura, Eisuke; Arikawa, Yasunobu; Nagai, Takahiro; Abe, Yuki; Ozaki, Satoshi; Noda, Akira

2016-03-01

To construct a unified experimental machine CANDY using a kJ DPSSL driver in the fast-ignition scheme, the Laser for Fast Ignition Experiment (LFEX) at Osaka is used, showing that the laser-driven ions heat the preimploded core of a deuterated polystyrene (CD) shell target from 0.8 keV to 2 keV, resulting in 5 x 108 DD neutrons best ever obtained in the scheme. 4-J/10-Hz DPSSL laser HAMA is for the first time applied to the CD shell implosion- core heating experiments in the fast ignition scheme to yield neutrons and also to a continuous target injection, which yields neutrons of 3 x 105 n/4πsr n/shot.

Distribution of Natural (U-238, Th-232, Ra-226) and Technogenic (Sr-90, Cs-137) Radionuclides in Soil-Plants Complex Near Issyk-Kul Lake, Kyrgyzstan

NASA Astrophysics Data System (ADS)

Jovanovic, L.; Kaldybaev, B.; Djenbaev, B.; Tilenbaev, A.

2012-04-01

Researches on radionuclides distribution in the soil-plants complex provide essential information in understanding human exposure to natural and technogenic sources of radiation. It is necessary in establishing regulation relating to radiation protection. The aim of this study was the radiochemical analysis of the content natural radionuclides 238U, 232Th,226Ra and technogenic radionuclides content (90Sr, 137Cs) in soils near Issyk-Kul lake (Kyrgyzstan). Results of radiochemical analyses have shown, that the concentrations of thorium-232 are fluctuating in the limits (11.7-84.1)-10-4% in the soils. The greatest concentration of thorium-232 has been found in the light chestnut soils. The content of uranium-238 in the soils near Issyk-Kul lake is fluctuating from 2.8 up to 12.7-10-4%. Radium-226 has more migration ability in comparison with other heavy natural radionuclides. According to our research the concentrations of radium-226 are fluctuating in the limits (9.4-43.0)-10-11%. The greatest concentration of radium-226 (43,0±2,8)-10-11% has been determined in the light chestnut soil. In connection with global migration of contaminating substances, including radioactive, the special attention is given long-lived radionuclides strontium-90 and caesium-137 in food-chains, and agroecosystems. Results of radiochemical analyses have shown, that specific activity of strontium-90 is fluctuating in the range of 2.9 up to 11.1 Bq/kg, and caesium-137 from 3.7 up to 14,3 Bq/kg in the soil of agroecosystems in the region of Issyk-Kul. In soil samples down to 1 meter we have observed vertical migration of these radionuclides, they were found to accumulate on the surface of soil horizon (0-5 cm) and their specific activity sharply decreases with depth. In addition in high-mountain pastures characterized by horizontal migration of cattle in profiles of soil, it was discovered that specific activity of radionuclides are lower on the slope than at the foot of the mountain. The content of natural radionuclides (238U, 232Th, 226Ra ) and technogenic radionuclides (90Sr, 137Cs) in the soils depend on many factors: the type and mechanical composition of soil, capacity of absorption, acidity, concentration of exchange forms of carbonates, organic substances. The radionuclides accumulation process in the plants depend on a specific accumulation ability of plants. During the researches it has been found that radionuclides accumulate in vegetative organs more than in reproductive parts of plants. According to the accumulation degrees of natural radionuclides plants taking place in the following decreasing series: sugar beet > potatoes > lucerne > clover > oats > perennial herbs > wheat > annual grass crops > barley > corn. Radiochemical analysis of the technogenic radionuclides in the plants has been determined that specific activity of strontium-90 is increased in leguminous plants (cobs of corn, lucerne) in comparison with other cultures. Caesium-137 is accumulated in beet roots, cobs of corn and lucerne. Key words: natural radionuclides, technogenic radionuclides, soil-plants complex, Issyk-Kul lake, Kyrgyzstan

An Econometrics Analysis on the Effect of Satisfaction for Foreign Graduate Students' Academic Performance in Taiwan

ERIC Educational Resources Information Center

Shih, Cheng Ping; Tillett, Denroy; Lawrence, Nadine

2012-01-01

Taiwan has proven and continues to prove its economic prowess as a fast and well developed nation. One theory to account for this accomplishment is its continued success in developing its best natural resource--its people--through education. A continuum of this practice is the implementation of Higher Education and then International Higher…

Highly efficient one-pot labeling of new phosphonium cations with fluorine-18 as potential PET agents for myocardial perfusion imaging.

PubMed

Zhao, Zuoquan; Yu, Qian; Mou, Tiantian; Liu, Chang; Yang, Wenjiang; Fang, Wei; Peng, Cheng; Lu, Jie; Liu, Yu; Zhang, Xianzhong

2014-11-03

Lipophilic cations such as phosphonium salts can accumulate in mitochondria of heart in response to the negative inner-transmembrane potentials. Two phosphonium salts [(18)F]FMBTP and [(18)F]mFMBTP were prepared and evaluated as potential myocardial perfusion imaging (MPI) agents in this study. The cations were radiolabeled via a simplified one-pot method starting from [(18)F]fluoride and followed by physicochemical property tests, in vitro cellular uptake assay, ex vivo mouse biodistribution, and in vivo rat microPET imaging. The total radiosynthesis time was less than 60 min including HPLC purification. The [(18)F] labeled compounds were obtained in high radiolabeling yield (∼50%) and good radiochemical purity (>99%). Both compounds were electropositive, and their log P values at pH 7.4 were 1.16 ± 0.003 (n = 3) and 1.05 ± 0.01 (n = 3), respectively. Both [(18)F]FMBTP and [(18)F]mFMBTP had high heart uptake (25.24 ± 2.97% ID/g and 31.02 ± 0.33% ID/g at 5 min postinjection (p.i.)) in mice with good retention (28.99 ± 3.54% ID/g and 26.82 ± 3.46% ID/g at 120 min p.i.). From the PET images in rats, the cations exhibited high myocardium uptake and fast clearance from liver and small intestine to give high-contrast images across all time points. These phosphonium cations were radiosynthesized via a highly efficient one-pot procedure for potential MPI offering high heart accumulation and rapid nontarget clearance.

Identifying factors associated with fast food consumption among adolescents in Beijing China using a theory-based approach.

PubMed

Ma, R; Castellanos, D C; Bachman, J

2016-07-01

China is in the midst of the nutrition transition with increasing rates of obesity and dietary changes. One contributor is the increase in fast food chains within the country. The purpose of this study was to develop a theory-based instrument that explores influencing factors of fast food consumption in adolescents residing in Beijing, China. Cross-sectional study. Value expectancy and theory of planned behaviour were utilised to explore influencing factors of fast food consumption in the target population. There were 201 Chinese adolescents between the ages of 12 and 18. Cronbach's alpha correlation coefficients were used to examine internal reliability of the theory-based questionnaire. Bivariate correlations and a MANOVA were utilised to determine the relationship between theory-based constructs, body mass index (BMI)-for-age and fast food intake frequency as well as to determine differences in theory-based scores among fast food consumption frequency groupings. The theory-based questionnaire showed good reliability. Furthermore, there was a significant difference in the theory-based subcategory scores between fast food frequency groups. A significant positive correlation was observed between times per week fast food was consumed and each theory-based subscale score. Using BMI-for-age of 176 participants, 81% were normal weight and 19% were considered overweight or obese. Results showed consumption of fast food to be on average 1.50 ± 1.33 per week. The relationship between BMI-for-age and times per week fast food was consumed was not significant. As the nutrition transition continues and fast food chains expand, it is important to explore factors effecting fast food consumption in China. Interventions targeting influencing factors can be developed to encourage healthy dietary choice in the midst of this transition. Copyright © 2016. Published by Elsevier Ltd.

Fast continuous tuning of terahertz quantum-cascade lasers by rear-facet illumination

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

Hempel, Martin, E-mail: hempel@pdi-berlin.de; Röben, Benjamin; Schrottke, Lutz

2016-05-09

GaAs-based terahertz quantum-cascade lasers (QCLs) are continuously tuned in their emission frequency by illuminating the rear facet with a near-infrared, high-power diode laser. For QCLs emitting around 3.1 THz, the maximum tuning range amounts to 2.8 GHz for continuous-wave operation at a heat sink temperature of 55 K, while in pulsed mode 9.1 and 8.0 GHz are achieved at 35 and 55 K, respectively.

On forward inferences of fast and slow readers. An eye movement study

PubMed Central

Hawelka, Stefan; Schuster, Sarah; Gagl, Benjamin; Hutzler, Florian

2015-01-01

Unimpaired readers process words incredibly fast and hence it was assumed that top-down processing, such as predicting upcoming words, would be too slow to play an appreciable role in reading. This runs counter the major postulate of the predictive coding framework that our brain continually predicts probable upcoming sensory events. This means, it may generate predictions about the probable upcoming word during reading (dubbed forward inferences). Trying to asses these contradictory assumptions, we evaluated the effect of the predictability of words in sentences on eye movement control during silent reading. Participants were a group of fluent (i.e., fast) and a group of speed-impaired (i.e., slow) readers. The findings indicate that fast readers generate forward inferences, whereas speed-impaired readers do so to a reduced extent - indicating a significant role of predictive coding for fluent reading. PMID:25678030

Intermittent fasting preserves beta-cell mass in obesity-induced diabetes via the autophagy-lysosome pathway.

PubMed

Liu, Haiyan; Javaheri, Ali; Godar, Rebecca J; Murphy, John; Ma, Xiucui; Rohatgi, Nidhi; Mahadevan, Jana; Hyrc, Krzysztof; Saftig, Paul; Marshall, Connie; McDaniel, Michael L; Remedi, Maria S; Razani, Babak; Urano, Fumihiko; Diwan, Abhinav

2017-01-01

Obesity-induced diabetes is characterized by hyperglycemia, insulin resistance, and progressive beta cell failure. In islets of mice with obesity-induced diabetes, we observe increased beta cell death and impaired autophagic flux. We hypothesized that intermittent fasting, a clinically sustainable therapeutic strategy, stimulates autophagic flux to ameliorate obesity-induced diabetes. Our data show that despite continued high-fat intake, intermittent fasting restores autophagic flux in islets and improves glucose tolerance by enhancing glucose-stimulated insulin secretion, beta cell survival, and nuclear expression of NEUROG3, a marker of pancreatic regeneration. In contrast, intermittent fasting does not rescue beta-cell death or induce NEUROG3 expression in obese mice with lysosomal dysfunction secondary to deficiency of the lysosomal membrane protein, LAMP2 or haplo-insufficiency of BECN1/Beclin 1, a protein critical for autophagosome formation. Moreover, intermittent fasting is sufficient to provoke beta cell death in nonobese lamp2 null mice, attesting to a critical role for lysosome function in beta cell homeostasis under fasting conditions. Beta cells in intermittently-fasted LAMP2- or BECN1-deficient mice exhibit markers of autophagic failure with accumulation of damaged mitochondria and upregulation of oxidative stress. Thus, intermittent fasting preserves organelle quality via the autophagy-lysosome pathway to enhance beta cell survival and stimulates markers of regeneration in obesity-induced diabetes.

Diffusion cannot govern the discharge of neurotransmitter in fast synapses.

PubMed Central

Khanin, R; Parnas, H; Segel, L

1994-01-01

In the present work we show that diffusion cannot provide the observed fast discharge of neurotransmitter from a synaptic vesicle during neurotransmitter release, mainly because it is not sufficiently rapid nor is it sufficiently temperature-dependent. Modeling the discharge from the vesicle into the cleft as a continuous point source, we have determined that discharge should occur in 50-75 microseconds, to provide the observed high concentrations of transmitter at the critical zone. Images FIGURE 5 PMID:7811953

New simple and low-cost methods for periodic checks of Cyclone® Plus Storage Phosphor System.

PubMed

Edalucci, Elisabetta; Maffione, Anna Margherita; Fornasier, Maria Rosa; De Denaro, Mario; Scian, Giovanni; Dore, Franca; Rubello, Domenico

2017-01-01

The recent large use of the Cyclone® Plus Storage Phosphor System, especially in European countries, as imaging system for quantification of radiochemical purity of radiopharmaceuticals raised the problem of setting the periodic controls as required by European Legislation. We described simple, low-cost methods for Cyclone® Plus quality controls, which can be useful to evaluate the performance measurement of this imaging system.

MEASUREMENT OF THE RADIOACTIVE CONTAMINATION OF THE FOOD CHAIN (in French)

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

Chevallier, A.; Schneider, R.

ABS>The results obtained at the Laboratoire de Protection of 1'Institut de Physique Biologique, Strasbourg, from 1958 to 1960 on the contamination of food are tabulated. The methods used for the measurement of the total beta activity and for the radiochemical separations and determination of the elements isolated are described for milk and vegetables. The activities found in milk, vegetables, and animal skeletons are given in tabular form. (J.S.R.)

Operation Ivy. Project 8. 4. Report to the Scientific Director. High-resolution spectroscopy at Ivy compared with previous tests

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

Beck, C.A.

1985-04-01

The high-resolution ultraviolet and visible spectra of typical test nuclear detonations up to and including Operation Ivy were analyzed and compared. Topics studied include the types of atomc and molecular material observed (with calculations, in some cases, of the relative quantities involved), the ultraviolet cutoff, and rotational temperatures. Variation of these quantities with the radiochemical yield of the bomb is indicated.

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

Brand, B.; Boos, W.

At high osmolarity, Escherichia coli synthesizes trehalose intracellularly, irrespective of the nature of the carbon source. Synthesis proceeds via the transfer of UDP-glucose to glucose 6-phosphate, yielding trehalose 6-phosphate, followed by its dephosphorylation to trehalose. This reaction was exploited to preparatively synthesize ({sup 14}C)trehalose from exogenous ({sup 14}C)glucose by using intact bacteria of a mutant (DF214) that could not metabolize glucose. The total yield of radiochemically pure trehalose from glucose was routinely more than 50%.

Bikini scientific resurvey. Volume II. Report of the technical director. Technical report

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

Not Available

1947-12-01

Contents: Island and Reef Geology; Submarine Geology; Drilling Operations; Radiobiology Studies; Reef and Lagoon Fishes; Pelagic Fishes; Taxonomy and Teratology of Fishes; Invertebrate Embryology; Vertebrate Embryology; Reef and Lagoon Algae; Chemical Effects of Organisms Upon Sea Water; The Insect Population; Marine Invertebrates; Land Animals; Plankton Studies; Counter-Room Activities; Radiochemical Analyses; Soils Chemistry; Low-Level Radiation Studies; Army Engineering Studies; Aerological Data; Bacteriological Investigations; Radiological Safety; Radiological Health; Technical Director's Summary.

Inorganic Halogen Oxidizer Research

DTIC Science & Technology

1975-02-26

K. 0. Christe and C. J. Schack, Advances Inorg. Chem. Radiochem. 15. "The NF * Radical Cation. Esr Studies of Radiation Effects in NF„+ Salts...and 25°) in a wide variety of polar and nonpolar solvents, such as aqueous solutions, alcohols, ketones , esters, ethers , and aromatic and halogenated... Studies of Radiation Effects in NF, Salts = 4 S. P. Mishra, M. C R. Symons, K. 0. Christe, R. D. Wilson and R. I. Wagner Received. . . August .9

Kinematic principles of primate rotational vestibulo-ocular reflex. I. Spatial organization of fast phase velocity axes

NASA Technical Reports Server (NTRS)

Hess, B. J.; Angelaki, D. E.

1997-01-01

The spatial organization of fast phase velocity vectors of the vestibulo-ocular reflex (VOR) was studied in rhesus monkeys during yaw rotations about an earth-horizontal axis that changed continuously the orientation of the head relative to gravity ("barbecue spit" rotation). In addition to a velocity component parallel to the rotation axis, fast phases also exhibited a velocity component that invariably was oriented along the momentary direction of gravity. As the head rotated through supine and prone positions, torsional components of fast phase velocity axes became prominent. Similarly, as the head rotated through left and right ear-down positions, fast phase velocity axes exhibited prominent vertical components. The larger the speed of head rotation the greater the magnitude of this fast phase component, which was collinear with gravity. The main sequence properties of VOR fast phases were independent of head position. However, peak amplitude as well as peak velocity of fast phases were both modulated as a function of head orientation, exhibiting a minimum in prone position. The results suggest that the fast phases of vestibulo-ocular reflexes not only redirect gaze and reposition the eye in the direction of head motion but also reorient the eye with respect to earth-vertical when the head moves relative to gravity. As further elaborated in the companion paper, the underlying mechanism could be described as a dynamic, gravity-dependent modulation of the coordinates of ocular rotations relative to the head.

High-intensity interval training or continuous training, combined or not with fasting, in obese or overweight women with cardiometabolic risk factors: study protocol for a randomised clinical trial

PubMed Central

Van Bavel, Diogo; de Moraes, Roger; Tibiriça, Eduardo V

2018-01-01

Introduction Physical inactivity and increased caloric intake play important roles in the pathophysiology of obesity. Increasing physical activity and modifying eating behaviours are first-line interventions, frequently hampered by lack of time to exercise and difficulties in coping with different diets. High-intensity interval training (HIIT) may be a time-efficient method compared with moderate-intensity continuous training (CT). Conversely, diets with a fasting component may be more effective than other complex and restrictive diets, as it essentially limits caloric intake to a specified period without major diet composition changes. Therefore, the combination of HIIT and fasting may provide incremental benefits in terms of effectiveness and time efficiency in obese and sedentary populations. The aim of this study is to determine the effect of HIIT versus CT, combined or not with fasting, on microcirculatory function, cardiometabolic parameters, anthropometric indices, cardiorespiratory fitness and quality of life in a population of sedentary overweight or obese women with cardiometabolic risk factors. Methods and analysis Sedentary women aged 30–50 years, with a body mass index ≥25 kg/m2 and cardiometabolic risk factors, will be randomised to HIIT performed in the fasting state, HIIT performed in the fed state, CT in the fasting state or CT in the fed state. Cardiometabolic parameters, anthropometric indices, cardiorespiratory fitness, quality of life and microvascular function (cutaneous capillary density and microvascular reactivity evaluated by laser speckle contrast imaging) will be evaluated before initiation of the interventions and 16 weeks thereafter. Ethics and dissemination The trial complies with the Declaration of Helsinki and has been approved by the local ethics committee (Instituto Nacional de Cardiologia, Rio de Janeiro, Brazil). All patients provide written informed consent before enrolment and randomisation. The study’s results will be disseminated to the healthcare community by publications and presentations at scientific meetings. Trial registration number NCT03236285. PMID:29705753

­­New Finite-Frequency Teleseismic P-wave Tomography of the Anatolian Sub-continent and the Fate of the Subducted Cyprean Slab

NASA Astrophysics Data System (ADS)

Portner, D. E.; Biryol, C. B.; Delph, J. R.; Beck, S. L.; Zandt, G.; Özacar, A.; Sandvol, E. A.; Turkelli, N.

2016-12-01

The eastern Mediterranean region is characterized by active subduction of Tethyan lithosphere beneath the Anatolian sub-continent at the Aegean and Cyprean trenches. The subduction system is historically characterized by slab roll-back, detachment, and slab settling in the mantle transition zone. Prior mantle tomography studies reveal segmentation of the subducted Tethyan lithosphere, which is thought to have a strong control on surface volcanism and uplift across Anatolia. However, tomographic resolution, particularly in central Anatolia, has been limited, thus making detailed delineations of the subducted slab segments difficult. To improve resolution, we combine two years of seismic data from the recent Continental Dynamics - Central Anatolia Tectonics (CD-CAT) seismic deployment and Turkey's national seismic network ( 33,000 residuals) to 33,000 travel time residuals from Biryol et al. (2011, GJI) in a new finite-frequency teleseismic P-wave tomographic inversion. Our new images reveal with detail a complicated geometry of fast velocity anomalies associated with subducted Tethyan lithosphere. At shallow depths, slow velocities separate the fast anomalies connected to the Aegean and Cyprean trenches. The fast anomaly connected to the Cyprean trench has an arcuate shape in map view, following the trace of the Central Taurus Mountains. This anomaly is separated from a high-amplitude block to the north that appears to dip sub-vertically throughout the upper mantle (200-660 km depth). Other blocks of fast material that may represent subducted Tethyan lithosphere appear down-dip of the vertical block. Additionally, our images indicate that some of the fast velocity anomalies previously seen to flatten in the mantle transition zone may continue into the lower mantle. Thus, our new images provide a more detailed picture of the fate of the Cyprean slab and suggest that some of the fast anomalies associated with the slab continue into the lower mantle, bringing to question the traditional view of a slab graveyard in the mantle transition zone in this region.

A robust and fast method of sampling and analysis of delta13C of dissolved inorganic carbon in ground waters.

PubMed

Spötl, Christoph

2005-09-01

The stable carbon isotopic composition of dissolved inorganic carbon (delta13C(DIC)) is traditionally determined using either direct precipitation or gas evolution methods in conjunction with offline gas preparation and measurement in a dual-inlet isotope ratio mass spectrometer. A gas evolution method based on continuous-flow technology is described here, which is easy to use and robust. Water samples (100-1500 microl depending on the carbonate alkalinity) are injected into He-filled autosampler vials in the field and analysed on an automated continuous-flow gas preparation system interfaced to an isotope ratio mass spectrometer. Sample analysis time including online preparation is 10 min and overall precision is 0.1 per thousand. This method is thus fast and can easily be automated for handling large sample batches.

Continuous-variable quantum key distribution in uniform fast-fading channels

NASA Astrophysics Data System (ADS)

Papanastasiou, Panagiotis; Weedbrook, Christian; Pirandola, Stefano

2018-03-01

We investigate the performance of several continuous-variable quantum key distribution protocols in the presence of uniform fading channels. These are lossy channels whose transmissivity changes according to a uniform probability distribution. We assume the worst-case scenario where an eavesdropper induces a fast-fading process, where she chooses the instantaneous transmissivity while the remote parties may only detect the mean statistical effect. We analyze coherent-state protocols in various configurations, including the one-way switching protocol in reverse reconciliation, the measurement-device-independent protocol in the symmetric configuration, and its extension to a three-party network. We show that, regardless of the advantage given to the eavesdropper (control of the fading), these protocols can still achieve high rates under realistic attacks, within reasonable values for the variance of the probability distribution associated with the fading process.

Automatic detection of recoil-proton tracks and background rejection criteria in liquid scintillator-micro-capillary-array fast neutron spectrometer

NASA Astrophysics Data System (ADS)

Mor, Ilan; Vartsky, David; Dangendorf, Volker; Tittelmeier, Kai.; Weierganz, Mathias; Goldberg, Mark Benjamin; Bar, Doron; Brandis, Michal

2018-06-01

We describe an analysis procedure for automatic unambiguous detection of fast-neutron-induced recoil proton tracks in a micro-capillary array filled with organic liquid scintillator. The detector is viewed by an intensified CCD camera. This imaging neutron detector possesses the capability to perform high position-resolution (few tens of μm), energy-dispersive transmission-imaging using ns-pulsed beams. However, when operated with CW or DC beams, it also features medium-quality spectroscopic capabilities for incident neutrons in the energy range 2-20 MeV. In addition to the recoil proton events which display a continuous extended track structure, the raw images exhibit complex ion-tracks from nuclear interactions of fast-neutrons in the scintillator, capillaries quartz-matrix and CCD. Moreover, as expected, one also observes a multitude of isolated scintillation spots of varying intensity (henceforth denoted "blobs") that originate from several different sources, such as: fragmented proton tracks, gamma-rays, heavy-ion reactions as well as events and noise that occur in the image-intensifier and CCD. In order to identify the continuous-track recoil proton events and distinguish them from all these background events, a rapid, computerized and automatic track-recognition-procedure was developed. Based on an appropriately weighted analysis of track parameters such as: length, width, area and overall light intensity, the method is capable of distinguishing a single continuous-track recoil proton from typically surrounding several thousands of background events that are found in each CCD frame.

Intermittent fasting during winter and spring affects body composition and reproduction of a migratory duck

USGS Publications Warehouse

Barboza, P.S.; Jorde, Dennis G.

2002-01-01

We compared food intake, body mass and body composition of male and female black ducks (Anas rubripes) during winter (January-March). Birds were fed the same complete diet ad libitum on consecutive days each week without fasting (control; nine male; nine female) or with either short fasts (2 day.week-1; nine male; nine female), or long fasts (4 day.week-1; eleven male; twelve female). We continued treatments through spring (March-May) to measure the effect of intermittent fasts on body mass and egg production. Daily food intake of fasted birds was up to four times that of unfasted birds. Weekly food intake of males was similar among treatments (364 g.kg-1.week-1) but fasted females consumed more than unfasted females in January (363 g.kg-1.week-1 vs. 225 g.kg-1.week-1). Although both sexes lost 10-14% body mass, fasted females lost less mass and lipid than unfasted females during winter. Total body nitrogen was conserved over winter in both sexes even though the heart and spleen lost mass while the reproductive tract and liver gained mass. Intermittent fasting increased liver, intestinal tissue and digesta mass of females but not of males. Fasting delayed egg production in spring but did not affect size, fertility or hatching of the clutch. Females on long fasts were still heavier than controls after laying eggs. Thus black ducks combine flexibility of food intake with plasticity of digestive tract, liver and adipose tissue when food supply is interrupted during winter. Females modulate body mass for survival and defer reproduction when food supply is interrupted in spring.

Non-Markovian continuous-time quantum walks on lattices with dynamical noise

NASA Astrophysics Data System (ADS)

Benedetti, Claudia; Buscemi, Fabrizio; Bordone, Paolo; Paris, Matteo G. A.

2016-04-01

We address the dynamics of continuous-time quantum walks on one-dimensional disordered lattices inducing dynamical noise in the system. Noise is described as time-dependent fluctuations of the tunneling amplitudes between adjacent sites, and attention is focused on non-Gaussian telegraph noise, going beyond the usual assumption of fast Gaussian noise. We observe the emergence of two different dynamical behaviors for the walker, corresponding to two opposite noise regimes: slow noise (i.e., strong coupling with the environment) confines the walker into few lattice nodes, while fast noise (weak coupling) induces a transition between quantum and classical diffusion over the lattice. A phase transition between the two dynamical regimes may be observed by tuning the ratio between the autocorrelation time of the noise and the coupling between the walker and the external environment generating the noise. We also address the non-Markovianity of the quantum map by assessing its memory effects, as well as evaluating the information backflow to the system. Our results suggest that the non-Markovian character of the evolution is linked to the dynamical behavior in the slow noise regime, and that fast noise induces a Markovian dynamics for the walker.

Continuous fast Fourier transforms cyclic voltammetry as a new approach for investigation of skim milk k-casein proteolysis, a comparative study.

PubMed

Shayeh, Javad Shabani; Sefidbakht, Yahya; Siadat, Seyed Omid Ranaei; Niknam, Kaveh

2017-10-01

Cheese production is relied upon the action of Rennet on the casein micelles of milk. Chymosin assay methods are usually time consuming and offline. Herein, we report a new electrochemical technique for studying the proteolysis of K-casein. The interaction of rennet and its substrate was studied by fast Fourier transform continuous cyclic voltammetry (FFTCCV) based on a determination of k-casein in aqueous solution. FFTCCV technique is a very useful method for studying the enzymatic procedures. Fast response, no need of modified electrodes or complex equipment is some of FFTCCV advantages. Various concentrations of enzyme and substrate were selected and the increase in the appearance of charged species in solution as a result of the addition of rennet was studied. Data obtained using FFTCCV technique were also confirmed by turbidity analysis. The results show that rennet proteolysis activity occurs in much shorter time scales compare with its aggregation. Hence, following the appearance of charged segments as a result of proteolysis could be under consideration as a rapid and online method. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Barton, B.A.; Schreck, C.B.; Fowler, L.G.

Juvenile chinook salmon (Oncorhynchus tshawytscha) reared on low-, medium-, or high-lipid diets for 18 weeks were either kept on their respective diets or fasted for 20 d; then they were subjected to a 30-s handling stress or to handling plus continuous confinement. In fish that were handled but not confined, poststress hyperglycemia was greatest in fed fish that received the high-lipid diet and was generally lower in fasted than in fed fish. Plasma cortisol elevations in response to handling or handling plus confinement stress were not appreciably affected by diet type or fasting. The result indicated that prior feeding regimesmore » and the types of diet fed should be considered when one is interpreting the magnitude of hyperglycemic stress responses in juvenile chinook salmon.« less

The effectiveness of robotic training depends on motor task characteristics.

PubMed

Marchal-Crespo, Laura; Rappo, Nicole; Riener, Robert

2017-12-01

Previous research suggests that the effectiveness of robotic training depends on the motor task to be learned. However, it is still an open question which specific task's characteristics influence the efficacy of error-modulating training strategies. Motor tasks can be classified based on the time characteristics of the task, in particular the task's duration (discrete vs. continuous). Continuous tasks require movements without distinct beginning or end. Discrete tasks require fast movements that include well-defined postures at the beginning and the end. We developed two games, one that requires a continuous movement-a tracking task-and one that requires discrete movements-a fast reaching task. We conducted an experiment with thirty healthy subjects to evaluate the effectiveness of three error-modulating training strategies-no guidance, error amplification (i.e., repulsive forces proportional to errors) and haptic guidance-on self-reported motivation and learning of the continuous and discrete games. Training with error amplification resulted in better motor learning than haptic guidance, besides the fact that error amplification reduced subjects' interest/enjoyment and perceived competence during training. Only subjects trained with error amplification improved their performance after training the discrete game. In fact, subjects trained without guidance improved the performance in the continuous game significantly more than in the discrete game, probably because the continuous task required greater attentional levels. Error-amplifying training strategies have a great potential to provoke better motor learning in continuous and discrete tasks. However, their long-lasting negative effects on motivation might limit their applicability in intense neurorehabilitation programs.

An improved radiosynthesis of [18F]AV-133: a PET imaging agent for vesicular monoamine transporter 2.

PubMed

Zhu, Lin; Liu, Yajing; Plössl, Karl; Lieberman, Brian; Liu, Jingying; Kung, Hank F

2010-02-01

Recently, a PET tracer, 9-[(18)F]fluoropropyl-(+)-dihydrotetrabenazine ([(18)F]AV-133), targeting vesicular monoamine transporter 2 (VMAT2) in the central nervous system has been reported. It is currently under Phase II clinical trials to establish its usefulness in the diagnosis of neurodegenerative diseases including dementia with Lewy bodies and Parkinson's disease. The radiolabeling of [(18)F]AV-133, nucleophilic fluorination reaction and potential effects of pseudo-carrier were evaluated by in vivo biodistribution. The preparation of [(18)F]AV-133 was evaluated under different conditions, specifically by employing different precursors (-OTs or -Br as the leaving group at the 9-propoxy position), reagents (K222/K(2)CO(3) vs. tributylammonium bicarbonate) and solvents (acetonitrile vs. DMSO), reaction temperature and reaction time. With optimized conditions from these experiments, radiosynthesis and purification with solid-phase extraction (SPE) of [(18)F]AV-133 were performed by an automated nucleophilic [(18)F]fluorination module. In vivo biodistribution in mice on [(18)F]AV-133 purified by either HPLC (no-carrier-added) or the SPE method (containing a pseudo-carrier) was performed and the results compared. Under a mild fluorination condition (heating at 115 degrees C for 5 min in dimethyl sulfoxide), [(18)F]AV-133 was obtained in a high yield using either -OTs or -Br as the leaving group. However, the -OTs precursor gave better radiochemical yields (>70%, thin layer chromatography analysis) compared to those of the -Br precursor. The optimized reaction conditions were successfully implemented to an automated nucleophilic fluorination module. Labeling and purification of [(18)F]AV133 were readily achieved via this automatic module in good radiochemical yield of 21-41% (n=10) in 40 min. The radiochemical purity was larger than 95%. Biodistribution of SPE-purified product (containing a pseudo-carrier) in mice showed a high striatum/cerebellum ratio (4.18+/-0.51), which was comparable to that of HPLC-purified [(18)F]AV-133 (4.51+/-0.10). The formation of [(18)F]AV-133 was evaluated under different labeling conditions. These improved labeling conditions and SPE purification were successfully implemented into an automated synthesis module. This offers a short preparation time (about 40 min), simplicity in operation and ready applicability for routine clinical operation. (c) 2010 Elsevier Inc. All rights reserved.

In vitro evaluation of a specific radiochemical compound based on 99mTc-labeled DARPinG3 for radionuclide imaging of tumors overexpressing Her-2/neu

NASA Astrophysics Data System (ADS)

Bragina, O.; Larkina, M.; Stasyuk, E.; Chernov, V.; Zelchan, R.; Medvedeva, A.; Sinilkin, I.; Yusubov, M.; Skuridin, V.; Deyev, S.; Buldakov, M.

2017-09-01

It is still necessary to search for new informative diagnostic methods to detect malignant tumors with overexpression of Her-2/neu, which are characterized by the aggressive course of the disease, rapid rate of tumor growth and low rates of relapse-free and overall survival. In recent years, the radioisotope techniques for detection of specific tumor targets have been developing actively. Purpose: to develop a chemically stable radiochemical compound for the targeted imaging of cells overexpressing Her-2/neu. Material and methods: The study was performed using 2 cell lines. The human breast adenocarcinoma HER2-overexpressing cell line BT-474 was chosen to detect specific binding. As a control, HER2-negative human breast adenocarcinoma MCF-7 was used. The human breast adenocarcinoma BT-474 and MCF-7 cell lines were seeded in chamber-slides at the density of 35,000 cells/ml in trypsin-EDTA (PanEco) medium and grown overnight at 37°C. After that both cell lines were washed with Phosphate buffered saline (PBS) and distributed into test tubes to 1 ml (5 millions cells in each). After adding 100 µl (70 MBq) studied complex of 99mTc-DPAH- DARPinG3 was incubated for 40 min at +4°C. Washing was performed three times with buffer PBS and 5% Bovine Serum Albumin (BSA). The characteristics of the binding specificity of the test set with the HER-2/neu receptor were determined by direct radiometric and planar scintigraphy. Nonparametric Mann-Whitney test was used to assess the differences in the quantitative characteristics between groups. Results: The output of the labeled complex was more than 91%, with a radiochemical purity of more than 94%. When carrying out a visual scintigraphic assessment much greater intensity accumulation of radiotracer was observed in the studied cell culture surface receptor overexpressing Her-2/neu. The results of direct radiometric also showed higher accumulation of the radiopharmaceutical in the adenocarcinoma cell line BT-474 human breast cancer overexpressing Her-2/neu compared to the control group. Conclusion: The preclinical studies demonstrated a high in vitro stability of the study compound, as well as its accumulation in the cell group overexpressing Her-2/neu.

Evaluation of Phosphatidylserine-Binding Peptides Radiolabeled with Fluorine 18 for in vivo Imaging of Apoptosis

NASA Astrophysics Data System (ADS)

Kapty, Janice Sarah

We currently do not have a clinical method to directly assess apoptosis induced by cancer therapies. Phosphatidylserine (PS) is an attractive target for imaging apoptosis since it is on the exterior of the apoptotic cells and PS externalization is an early marker of apoptosis. PS-binding peptides are an attractive option for developing an imaging probe to detect apoptosis using positron emission tomography. In this study we evaluated binding characteristics of PS-binding peptides for ability to bind to PS, radiolabeled PS-binding peptides with fluorine-18, and performed in vitro and in vivo analysis of 18F radiolabeled PS-binding peptides including biodistribution analysis and dynamic PET imaging in a murine tumor model of apoptosis. Four peptides were evaluated for PS binding characteristics using a plate based assay system, a liposome mimic of cell membrane PS presentation, and a cell assay of apoptosis. The results indicate that all four peptides bind to PS and are specific to apoptotic cells. The widely used 18 F prosthetic group N-succinimidyl-4-[18F]fluorobenzoate ([18F]SFB) and the recently developed N-[6-(4-[ 18F]fluorobenzylidene) aminooxyhexyl]maleimide ([18F]FBAM) were investigated for radiolabeling of two representative phosphatidylserine-binding peptides. The prosthetic groups were compared with respect to required reaction conditions for optimum labeling, radiolabeling yield and chemoselectivity. The N-terminus labeled product produced by reaction of [18F]SFB with binding peptide LIKKPF was produced in 18% radiochemical yield while no N-terminus labeled product could be isolated following [18F]SFB reaction with PDGLSR. When the peptides were modified by addition of a cysteine residue at the N-terminus they provided almost quantitative radiochemical yields with [18F]FBAM. Results indicate that for the peptides in this study, [18F]FBAM is a more useful prosthetic group compared to [18F]SFB due to its excellent chemo-selectivity and high radiochemical yield. We report the first experiments where PS-binding peptides were radiolabeled with 18F and evaluated as possible radiotracers for imaging apoptosis. We investigated two radio-peptides ([ 18F]FBAM-CLIKKPF and [18F]FBAM-CPGDLSR) in vitro and in vivo as possible radiotracers able to bind to apoptotic cells and to image chemotherapy induced apoptosis.

Acute regulation of plasma leptin by isoprenaline in lean and obese fasted subjects.

PubMed

Baynes, K C R; Nicholas, M D; Shojaee-Moradie, F; Umpleby, A M; Giannoulis, M G

2006-07-01

In human obesity, there is some evidence for impaired adrenergic sensitivity with respect to catecholamine-induced lipolysis. The beta-adrenoceptor agonist isoprenaline has been shown to suppress plasma leptin levels in lean humans in vivo. We hypothesized that a reduced adrenergic sensitivity in obese humans would result in impaired suppression of leptin secretion. Eight obese [Ob, body mass index (BMI) = 33.3 kg/m2] and seven lean (Ln, BMI = 21.8 kg/m2) men were studied after an overnight fast. Intravenous isoprenaline infusion was initiated at a rate of 8 ng/kg/min, titrated up to 24 ng/kg/min over 30 min and continued at this rate for a further 120 min with continuous electrocardiogram monitoring. Baseline fasting plasma leptin was higher in obese compared with lean subjects (Ob 12.2 +/- 1.8, Ln 2.6 +/- 0.6 ng/ml, p < 0.05 unpaired t-test). Baseline fasting glycerol as a measure of lipolysis was similar in both groups (Ob 62.9 +/- 7.6, Ln 42.4 +/- 8.9 micromol/l) and increased from baseline to 150 min by equivalent amounts (Ob +66.9%, Ln +81.2%, p = NS). Plasma leptin decreased from baseline to 150 min with similar relative changes in both groups (Ob -29.2%, Ln -27.8%). Obese subjects show a similar lipolytic and leptin response to acute isoprenaline infusion compared with lean subjects. Impaired beta-adrenergic-induced inhibition of leptin secretion does not appear to contribute to hyperleptinaemia in obese human subjects.

Detecting Earthquakes over a Seismic Network using Single-Station Similarity Measures

NASA Astrophysics Data System (ADS)

Bergen, Karianne J.; Beroza, Gregory C.

2018-03-01

New blind waveform-similarity-based detection methods, such as Fingerprint and Similarity Thresholding (FAST), have shown promise for detecting weak signals in long-duration, continuous waveform data. While blind detectors are capable of identifying similar or repeating waveforms without templates, they can also be susceptible to false detections due to local correlated noise. In this work, we present a set of three new methods that allow us to extend single-station similarity-based detection over a seismic network; event-pair extraction, pairwise pseudo-association, and event resolution complete a post-processing pipeline that combines single-station similarity measures (e.g. FAST sparse similarity matrix) from each station in a network into a list of candidate events. The core technique, pairwise pseudo-association, leverages the pairwise structure of event detections in its network detection model, which allows it to identify events observed at multiple stations in the network without modeling the expected move-out. Though our approach is general, we apply it to extend FAST over a sparse seismic network. We demonstrate that our network-based extension of FAST is both sensitive and maintains a low false detection rate. As a test case, we apply our approach to two weeks of continuous waveform data from five stations during the foreshock sequence prior to the 2014 Mw 8.2 Iquique earthquake. Our method identifies nearly five times as many events as the local seismicity catalog (including 95% of the catalog events), and less than 1% of these candidate events are false detections.

Positron emission tomography-guided conformal fast neutron therapy for glioblastoma multiforme

PubMed Central

Stelzer, Keith J.; Douglas, James G.; Mankoff, David A.; Silbergeld, Daniel L.; Krohn, Kenneth A.; Laramore, George E.; Spence, Alexander M.

2008-01-01

Glioblastoma multiforme (GBM) continues to be a difficult therapeutic challenge. Our study was conducted to determine whether improved survival and tumor control could be achieved with modern delivery of fast neutron radiation using three-dimensional treatment planning. Ten patients were enrolled. Eligibility criteria included pathologic diagnosis of GBM, age ≥ 18 years, and KPS ≥60. Patients underwent MRI and 18F-fluorodeoxyglucose PET (FDG PET) as part of initial three-dimensional treatment planning. Sequential targets were treated with noncoplanar fields to a total dose of 18 Gy in 16 fractions over 4 weeks. Median and 1-year overall survival were 55 weeks and 60%, respectively. One patient remains alive at last follow-up 255 weeks after diagnosis. Median progression-free survival was 16 weeks, and all patients had tumor progression by 39 weeks. Treatment was clinically well tolerated, but evidence of mild to moderate gliosis and microvascular sclerosis consistent with radiation injury was observed at autopsy in specimens taken from regions of contralateral brain that received approximately 6–10 Gy. Fast neutron radiation using modern imaging, treatment planning, and beam delivery was feasible to a total dose of 18 Gy, but tumor control probability was poor in comparison to that predicted from a dose-response model based on older studies. Steep dose-response curves for both tumor control and neurotoxicity continue to present a challenge to establishing a therapeutic window for fast neutron radiation in GBM, even with modern techniques. PMID:18055860

Hybrid suboptimal control of multi-rate multi-loop sampled-data systems

NASA Technical Reports Server (NTRS)

Shieh, Leang S.; Chen, Gwangchywan; Tsai, Jason S. H.

1992-01-01

A hybrid state-space controller is developed for suboptimal digital control of multirate multiloop multivariable continuous-time systems. First, an LQR is designed for a continuous-time subsystem which has a large bandwidth and is connnected in the inner loop of the overall system. The designed LQR would optimally place the eigenvalues of a closed-loop subsystem in the common region of an open sector bounded by sector angles + or - pi/2k for k = 2 or 3 from the negative real axis and the left-hand side of a vertical line on the negative real axis in the s-plane. Then, the developed continuous-time state-feedback gain is converted into an equivalent fast-rate discrete-time state-feedback gain via a digital redesign technique (Tsai et al. 1989, Shieh et al. 1990) reviewed here. A real state reconstructor is redeveloped utilizing the fast-rate input-output data of the system of interest. The design procedure of multiloop multivariable systems using multirate samplers is shown, and a terminal homing missile system example is used to demonstrate the effectiveness of the proposed method.

Real-time high-resolution heterodyne-based measurements of spectral dynamics in fibre lasers

PubMed Central

Sugavanam, Srikanth; Fabbri, Simon; Le, Son Thai; Lobach, Ivan; Kablukov, Sergey; Khorev, Serge; Churkin, Dmitry

2016-01-01

Conventional tools for measurement of laser spectra (e.g. optical spectrum analysers) capture data averaged over a considerable time period. However, the generation spectrum of many laser types may involve spectral dynamics whose relatively fast time scale is determined by their cavity round trip period, calling for instrumentation featuring both high temporal and spectral resolution. Such real-time spectral characterisation becomes particularly challenging if the laser pulses are long, or they have continuous or quasi-continuous wave radiation components. Here we combine optical heterodyning with a technique of spatio-temporal intensity measurements that allows the characterisation of such complex sources. Fast, round-trip-resolved spectral dynamics of cavity-based systems in real-time are obtained, with temporal resolution of one cavity round trip and frequency resolution defined by its inverse (85 ns and 24 MHz respectively are demonstrated). We also show how under certain conditions for quasi-continuous wave sources, the spectral resolution could be further increased by a factor of 100 by direct extraction of phase information from the heterodyned dynamics or by using double time scales within the spectrogram approach. PMID:26984634

Computational system identification of continuous-time nonlinear systems using approximate Bayesian computation

NASA Astrophysics Data System (ADS)

Krishnanathan, Kirubhakaran; Anderson, Sean R.; Billings, Stephen A.; Kadirkamanathan, Visakan

2016-11-01

In this paper, we derive a system identification framework for continuous-time nonlinear systems, for the first time using a simulation-focused computational Bayesian approach. Simulation approaches to nonlinear system identification have been shown to outperform regression methods under certain conditions, such as non-persistently exciting inputs and fast-sampling. We use the approximate Bayesian computation (ABC) algorithm to perform simulation-based inference of model parameters. The framework has the following main advantages: (1) parameter distributions are intrinsically generated, giving the user a clear description of uncertainty, (2) the simulation approach avoids the difficult problem of estimating signal derivatives as is common with other continuous-time methods, and (3) as noted above, the simulation approach improves identification under conditions of non-persistently exciting inputs and fast-sampling. Term selection is performed by judging parameter significance using parameter distributions that are intrinsically generated as part of the ABC procedure. The results from a numerical example demonstrate that the method performs well in noisy scenarios, especially in comparison to competing techniques that rely on signal derivative estimation.

21 CFR 520.2045 - Pyrantel tartrate powder; pyrantel tartrate pellets.

Code of Federal Regulations, 2014 CFR

2014-04-01

... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS... pounds and over are administered 5 pounds of ration per animal. (iii) Fast pigs over night for optimum...

Molecular imaging of σ receptors: synthesis and evaluation of the potent σ1 selective radioligand [18F]fluspidine.

PubMed

Fischer, Steffen; Wiese, Christian; Maestrup, Eva Grosse; Hiller, Achim; Deuther-Conrad, Winnie; Scheunemann, Matthias; Schepmann, Dirk; Steinbach, Jörg; Wünsch, Bernhard; Brust, Peter

2011-03-01

Neuroimaging of σ(1) receptors in the human brain has been proposed for the investigation of the pathophysiology of neurodegenerative and psychiatric diseases. However, there is a lack of suitable (18)F-labelled PET radioligands for that purpose. The selective σ(1) receptor ligand [(18)F]fluspidine (1'-benzyl-3-(2-[(18)F]fluoroethyl)-3H-spiro[[2]benzofuran-1,4'-piperidine]) was synthesized by nucleophilic (18)F(-) substitution of the tosyl precursor. In vitro receptor binding affinity and selectivity were assessed by radioligand competition in tissue homogenate and autoradiographic approaches. In female CD-1 mice, in vivo properties of [(18)F]fluspidine were evaluated by ex vivo brain section imaging and organ distribution of intravenously administered radiotracer. Target specificity was validated by organ distribution of [(18)F]fluspidine after treatment with 1 mg/kg i.p. of the σ receptor antagonist haloperidol or the emopamil binding protein (EBP) inhibitor tamoxifen. In vitro metabolic stability and in vivo metabolism were investigated by LC-MS(n) and radio-HPLC analysis. [(18)F]Fluspidine was obtained with a radiochemical yield of 35-45%, a radiochemical purity of ≥ 99.6% and a specific activity of 150-350 GBq/μmol (n = 6) within a total synthesis time of 90-120 min. In vitro, fluspidine bound specifically and with high affinity to σ(1) receptors (K (i) = 0.59 nM). In mice, [(18)F]fluspidine rapidly accumulated in brain with uptake values of 3.9 and 4.7%ID/g and brain to blood ratios of 7 and 13 at 5 and 30 min after intravenous application of the radiotracer, respectively. By ex vivo autoradiography of brain slices, resemblance between binding site occupancy of [(18)F]fluspidine and the expression of σ(1) receptors was shown. The radiotracer uptake in the brain as well as in peripheral σ(1) receptor expressing organs was significantly inhibited by haloperidol but not by tamoxifen. Incubation with rat liver microsomes led to a fast biotransformation of fluspidine. After an incubation period of 30 min only 13% of the parent compound was left. Seven metabolites were identified by HPLC-UV and LC-MS(n) techniques. However, [(18)F]fluspidine showed a higher metabolic stability in vivo. In plasma samples ∼ 94% of parent compound remained at 30 min and ∼ 67% at 60 min post-injection. Only one major radiometabolite was detected. None of the radiometabolites crossed the blood-brain barrier. [(18)F]Fluspidine demonstrated favourable target affinity and specificity as well as metabolic stability both in vitro and in animal experiments. The in vivo properties of [(18)F]fluspidine offer a high potential of this radiotracer for neuroimaging and quantitation of σ(1) receptors in vivo.

Synthesis and evaluation of a radiolabeled bis-zinc(II)-cyclen complex as a potential probe for in vivo imaging of cell death.

PubMed

Wang, Hongliang; Wu, Zhifang; Li, Sijin; Hu, Kongzhen; Tang, Ganghua

2017-04-01

The exposition of phosphatidylserine (PS) from the cell membrane is associated with most cell death programs (apoptosis, necrosis, autophagy, mitotic catastrophe, etc.), which makes PS an attractive target for overall cell death imaging. To this end, zinc(II) macrocycle coordination complexes with cyclic polyamine units as low-molecular-weight annexin mimics have a selective affinity for biomembrane surfaces enriched with PS, and are therefore useful for detection of cell death. In the present study, a 11 C-labeled zinc(II)-bis(cyclen) complex ( 11 C-CyclenZn2) was prepared and evaluated as a new positron emission tomography (PET) probe for cell death imaging. 11 C-CyclenZn2 was synthesized by methylation of its precursor, 4-methoxy-2,5-di-[10-methyl-1,4,7,10-tetraazacyclododecane-1,4,7-tricarboxylic acid tri-tert-butyl ester] phenol (Boc-Cyclen2) with 11 C-methyl triflate as a prosthetic group in acetone, deprotection by hydrolysis in aqueous HCl solution, and chelation with zinc nitrate. The cell death imaging capability of 11 C-CyclenZn2 was evaluated using in vitro cell uptake assays with camptothecin-treated PC-3 cells, biodistribution studies, and in vivo PET imaging in Kunming mice bearing S-180 fibrosarcoma. Starting from 11 C-methyl triflate, the total preparation time for 11 C-CyclenZn2 was ~40 min, with an uncorrected radiochemical yield of 12 ± 3% (based on 11 C-CH 3 OTf, n = 10), a radiochemical purity of greater than 95%, and the specific activity of 0.75-1.01 GBq/μmol. The cell death binding specificity of 11 C-CyclenZn2 was demonstrated by significantly different uptake rates in camptothecin-treated and control PC-3 cells in vitro. Inhibition experiments for 18 F-radiofluorinated Annexin V binding to apoptotic/necrotic cells illustrated the necessity of zinc ions for zinc(II)-bis(cyclen) complexation in binding cell death, and zinc(II)-bis(cyclen) complexe and Annexin V had not identical binding pattern with apoptosis/necrosis cells. Biodistribution studies of 11 C-CyclenZn2 revealed a fast clearance from blood, low uptake rates in brain and muscle tissue, and high uptake rates in liver and kidney, which provide the main metabolic route. PET imaging using 11 C-CyclenZn2 revealed that cyclophosphamide-treated mice (CP-treated group) exhibited a significant increase of uptake rate in the tumor at 60 min postinjection, compared with control mice (Control group). The results indicate that the ability of 11 C-CyclenZn2 to detect cell death is comparable to Annexin V, and it has potential as a PET tracer for noninvasive evaluation and monitoring of anti-tumor chemotherapy.

Differences in perceptions and fast food eating behaviours between Indians living in high- and low-income neighbourhoods of Chandigarh, India

PubMed Central

2013-01-01

Background Increased density of fast food restaurants is associated with increased prevalence of obesity in developed countries. However, less is known about this relationship in developing countries undergoing rapid urbanization and how differences in neighbourhood income affect the patronage of fast food outlets. The purpose of the study is to explore the differences in fast food preferences, perceptions, and patronage between Indians living in high- and low-income neighbourhoods. Methods This cross-sectional study recruited 204 men and women (35 to 65 years in age) from high- and low-income neighbourhoods who completed a questionnaire on fast food consumption. The questionnaire asked participants to define fast food and to provide reasons for and frequency of visits to fast food restaurants. The differences were analyzed using Chi square and t-tests for categorical and continuous variables, respectively. Results Participants from a high-income neighbourhood were more likely to perceive Western -style fast food as fast food, while people from the low-income neighbourhood were more likely to identify food sold by street vendors as fast food (p <0.001). Furthermore, compared to participants from the high-income neighbourhood, people from the low-income neighbourhood were more likely to report buying food from street vendors while less likely to dine out at both fast food and non-fast food restaurants (p<0.001). Although the high-income neighbourhood group was more likely to report enjoying eating at fast food restaurants than their low-income neighbourhood counterparts, there were no significant differences in the reasons for visiting fast food restaurants (convenience, price, social enjoyment, and quality of meals) between the two groups. Both groups preferred home cooked over restaurant meals, and they recognized that home cooked food was healthier. Conclusions Overall, consumption of fast food was low. People from a high-income neighbourhood dined out more frequently and were more likely to perceive Western-style food as fast food compared to their counterparts from the low-income neighbourhood. PMID:23289746

Chemical isolation of .sup.82 Sr from proton-irradiated Mo targets

DOEpatents

Grant, Patrick M.; Kahn, Milton; O'Brien, Jr., Harold A.

1976-01-01

Spallation reactions are induced in Mo targets with 200-800 MeV protons to produce microcurie to millicurie amounts of a variety of radionuclides. A six-step radiochemical procedure, incorporating precipitation, solvent extractions, and ion exchange techniques, has been developed for the separation and purification of Sr radioactivities from other spallation products and the bulk target material. Radiostrontium can be quantitatively recovered in a sufficiently decontaminated state for use in biomedical generator development.

[Determination of americium-241 in urine].

PubMed

Shvydko, N S; Mikhaĭlova, O A; Popov, D K

1988-01-01

A technique has been developed for the determination of americium 241 in urine by a radiochemical purification of the nuclide from uranium (upon co-precipitation of americium 241 with calcium and lanthanum), plutonium, thorium, and polonium 210 (upon co-precipitation of these radionuclides with zirconium iodate). alpha-Radioactivity was measured either in a thick layer of the americium 241 precipitate with a nonisotope carrier or in thin-layer preparations after electrolytic precipitation of americium 241 on a cathode.

18F-Labeling of Sensitive Biomolecules for Positron Emission Tomography

PubMed Central

Krishnan, Hema S.; Ma, Longle; Vasdev, Neil; Liang, Steven H.

2017-01-01

Positron emission tomography (PET) imaging study of fluorine-18 labeled biomolecules is an emerging and rapidly growing area for preclinical and clinical research. The present review focuses on recent advances in radiochemical methods for incorporating fluorine-18 into biomolecules via ‘direct’ or ‘indirect’ bioconjugation. Recently developed prosthetic groups and pre-targeting strategies, as well as representative examples in 18F-labeling of biomolecules in PET imaging research studies are highlighted. PMID:28704575

THE DETERMINATION OF URANIUM BURNUP IN MWD/TON

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

Rider, B.F.; Russell, J.L. Jr.; Harris, D.W.

The mass-spectrometric and radiochemical methods for the determination of burn-up in nuclear fuel are compared for reliability in the range of 5000 to 15,000 Mwd/ton. Neither appears to be clearly superior to the other. Each appears to have an uncertainty of approximately 6 to 8%. It is concluded that both methods of analysis should be employed where reliability is of great concern. Agreement between both methods is the best possible indication of reliable results. (auth)

Radiochemical purity, at expiry, and radiochemical stability of iodine-131 labelled meta-iodobenzylguanidine concentrates for intravenous infusion.

PubMed

Wafelman, A R; Hoefnagel, C A; Maes, R A; Beijnen, J H

1996-08-01

The determination of the amount of free [131I]iodide in [131I]metaiodobenzylguanidine ([131I]MIBG) concentrates for intravenous infusion under different storage conditions derived from daily practice. The percentage of free [131I]iodide was determined in [131I]MIBG concentrates (1.6-3.9 GBq in 7.5 ml), kept on dry ice (up to expiry, 3 days after production) or, after thawing, at room temperature (up to 24 h). A validated solid phase extraction (SPE) assay was used. Free [131I]iodide increased from 1.9% +/- 0.34% at production to 4.4% +/- 0.67% (mean +/- SD; n = 5) at expiry in 3.7 GBq per 7.5 ml [131I]MIBG infusion concentrates stored on dry ice (-78 degrees C). At room temperature, formation of free [131I]iodide was found to be dependent on the radioactive concentration of the fluid. [131I]iodide levels increased from 3.1%, immediately after thawing, to 6.6% and 16.6% at t = 5 and 24 h, respectively, for a 3.9 GBq per 7.5 ml concentrate. The investigated formulation of [131I]MIBG concentrates, stored in its original packing containing dry ice, can generally be used up to expiry. After thawing, the undiluted concentrates should be administered to a patient within 3.5 h.

Isolation of 236U and 239,240Pu from seawater samples and its determination by Accelerator Mass Spectrometry.

PubMed

López-Lora, Mercedes; Chamizo, Elena; Villa-Alfageme, María; Hurtado-Bermúdez, Santiago; Casacuberta, Núria; García-León, Manuel

2018-02-01

In this work we present and evaluate a radiochemical procedure optimised for the analysis of 236 U and 239,240 Pu in seawater samples by Accelerator Mass Spectrometry (AMS). The method is based on Fe(OH) 3 co-precipitation of actinides and uses TEVA® and UTEVA® extraction chromatography resins in a simplified way for the final U and Pu purification. In order to improve the performance of the method, the radiochemical yields are analysed in 1 to 10L seawater volumes using alpha spectrometry (AS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Robust 80% plutonium recoveries are obtained; however, it is found that Fe(III) concentration in the precipitation solution and sample volume are the two critical and correlated parameters influencing the initial uranium extraction through Fe(OH) 3 co-precipitation. Therefore, we propose an expression that optimises the sample volume and Fe(III) amounts according to both the 236 U and 239,240 Pu concentrations in the samples and the performance parameters of the AMS facility. The method is validated for the current setup of the 1MV AMS system (CNA, Sevilla, Spain), where He gas is used as a stripper, by analysing a set of intercomparison seawater samples, together with the Laboratory of Ion Beam Physics (ETH, Zürich, Switzerland). Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of solvent extraction and extraction chromatography resin techniques for uranium isotopic characterization in high-level radioactive waste and barrier materials.

PubMed

Hurtado-Bermúdez, Santiago; Villa-Alfageme, María; Mas, José Luis; Alba, María Dolores

2018-07-01

The development of Deep Geological Repositories (DGP) to the storage of high-level radioactive waste (HLRW) is mainly focused in systems of multiple barriers based on the use of clays, and particularly bentonites, as natural and engineered barriers in nuclear waste isolation due to their remarkable properties. Due to the fact that uranium is the major component of HLRW, it is required to go in depth in the analysis of the chemistry of the reaction of this element within bentonites. The determination of uranium under the conditions of HLRW, including the analysis of silicate matrices before and after the uranium-bentonite reaction, was investigated. The performances of a state-of-the-art and widespread radiochemical method based on chromatographic UTEVA resins, and a well-known and traditional method based on solvent extraction with tri-n-butyl phosphate (TBP), for the analysis of uranium and thorium isotopes in solid matrices with high concentrations of uranium were analysed in detail. In the development of this comparison, both radiochemical approaches have an overall excellent performance in order to analyse uranium concentration in HLRW samples. However, due to the high uranium concentration in the samples, the chromatographic resin is not able to avoid completely the uranium contamination in the thorium fraction. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluation of radiochemical neutron activation analysis methods for determination of arsenic in biological materials.

PubMed

Paul, Rick L

2011-01-01

Radiochemical neutron activation analysis (RNAA) with retention on hydrated manganese dioxide (HMD) has played a key role in the certification of As in biological materials at NIST. Although this method provides very high and reproducible yields and detection limits at low microgram/kilogram levels, counting geometry uncertainties may arise from unequal distribution of As in the HMD, and arsenic detection limits may not be optimal due to significant retention of other elements. An alternate RNAA procedure with separation of arsenic by solvent extraction has been investigated. After digestion of samples in nitric and perchloric acids, As(III) is extracted from 2 M sulfuric acid solution into a solution of zinc diethyldithiocarbamate in chloroform. Counting of (76)As allows quantitation of arsenic. Addition of an (77)As tracer solution prior to dissolution allows correction for chemical yield and counting geometries, further improving reproducibility. The HMD and solvent extraction procedures for arsenic were compared through analysis of SRMs 1577c (bovine liver), 1547 (peach leaves), and 1575a (pine needles). Both methods gave As results in agreement with certified values with comparable reproducibility. However, the solvent extraction method yields a factor of 3 improvement in detection limits and is less time-consuming than the HMD method. The new method shows great promise for use in As certification in reference materials.

Production, Labeling and In Vivo Studies with the Theranostic Positron-Emitting Radiometals 44Sc, 55/58m/58gCo, 61/64Cu, 86Y and 69Ge =

NASA Astrophysics Data System (ADS)

Valdovinos, Hector Francisco

In this dissertation, novel radiochemical separation methods for these radiometals that satisfy such requirements are presented, including a detailed characterization of the separated radionuclide in terms of radionuclidic purity, specific activity and spatial resolution in a small animal PET scanner. This dissertation also presents novel targetry and radiochemical separation methods for the production of less conventional radiometals that constitute "theranostic" (therapeutic and diagnostic) pairs, namely the Auger electron emitters 58mCo and 71Ge and their positron emitting complements 55Co and 69Ge. The theranostic potential of each radiometal is demonstrated first by collecting biodistribution data from PET imaging of tumor-bearing mice intravenously injected with radiolabeled agents, followed by internal dosimetry calculations focusing on the therapeutic and radiotoxic implications caused by the agent. Special attention is given to the radionuclides with intrinsic theranostic properties in themselves: 64Cu and the parent-daughter pair 58m/58gCo. The radiolabeled agents that are employed include the radiometal by itself, that is, weakly bound to a simple ligand in solution (all radiometals), as well as strongly bound to a chelator-conjugated tumor-targeting antibody called TRC105 (55Co, 58mCo, 58gCo, 64Cu and 86Y) or incorporated into the structure of a super paramagnetic iron oxide nanoparticle (69Ge).

Preparation and Quality Control of 68Ga-Citrate for PET Applications

PubMed Central

Aghanejad, Ayuob; Jalilian, Amir Reza; Ardaneh, Khosro; Bolourinovin, Fatemeh; Yousefnia, Hassan; Samani, Ali Bahrami

2015-01-01

Objective(s): In nuclear medicine studies, gallium-68 (8Ga) citrate has been recently known as a suitable infection agent in positron emission tomography (PET). In this study, by applying an in-house produced 68Ge/68Ga generator, a simple technique for the synthesis and quality control of 68Ga-citrate was introduced; followed by preliminary animal studies. Methods: 68GaCl3 eluted from the generator was studied in terms of quality control factors including radiochemical purity (assessed by HPLC and RTLC), chemical purity (assessed by ICP-EOS), radionuclide purity (evaluated by HPGe), and breakthrough. 68Ga-citrate was prepared from eluted 68GaCl3 and sodium citrate under various reaction conditions. Stability of the complex was evaluated in human serum for 2 h at 370C, followed by biodistribution studies in rats for 120 min. Results: 68Ga-citrate was prepared with acceptable radiochemical purity (>97 ITLC and >98% HPLC), specific activity (4-6 GBq/mM), chemical purity (Sn, Fe<0.3 ppm and Zn<0.2 ppm) within 15 min at 500C. The biodistribution of 68Ga-citrate was consistent with former reports up to 120 minutes. Conclusion: This study demonstrated the possible in-house preparation and quality control of 68Ga-citrate, using a commercially available 68Ge/68Ga generator for PET imaging throughout the country. PMID:27408889

Radiosynthesis of the anticancer nucleoside analogue Trifluridine using an automated 18F-trifluoromethylation procedure† †Electronic supplementary information (ESI) available: 1H NMR and 13C NMR data for characterised compounds, automation setup, HPLC traces from radiosynthesis, Log D7.4 and radiotracer stability procedures, raw data and HPLC traces from all in vitro and in vivo studies. See DOI: 10.1039/c8ob00432c

PubMed Central

King, Alice; Doepner, Andreas; Turton, David; Ciobota, Daniela M.; Da Pieve, Chiara; Wong Te Fong, Anne-Christine; Kramer-Marek, Gabriela; Chung, Yuen-Li

2018-01-01

Trifluoromethyl groups are widespread in medicinal chemistry, yet there are limited 18F-radiochemistry techniques available for the production of the complementary PET agents. Herein, we report the first radiosynthesis of the anticancer nucleoside analogue trifluridine, using a fully automated, clinically-applicable 18F-trifluoromethylation procedure. [18F]Trifluridine was obtained after two synthetic steps in <2 hours. The isolated radiochemical yield was 3% ± 0.44 (n = 5), with a radiochemical purity >99%, and a molar activity of 0.4 GBq μmol–1 ± 0.05. Biodistribution and PET-imaging data using HCT116 tumour-bearing mice showed a 2.5 %ID g–1 tumour uptake of [18F]trifluridine at 60 minutes post-injection, with bone uptake becoming a prominent feature thereafter. In vivo metabolite analysis of selected tissues revealed the presence of the original radiolabelled nucleoside analogue, together with deglycosylated and phosphorylated [18F]trifluridine as the main metabolites. Our findings suggest a potential role for [18F]trifluridine as a PET radiotracer for elucidation of drug mechanism of action. PMID:29629716

Radiosynthesis and Biodistribution of 99mTc-Metronidazole as an Escherichia coli Infection Imaging Radiopharmaceutical.

PubMed

Iqbal, Anam; Naqvi, Syed Ali Raza; Rasheed, Rashid; Mansha, Asim; Ahmad, Matloob; Zahoor, Ameer Fawad

2018-05-01

Bacterial infection poses life-threatening challenge to humanity and stimulates to the researchers for developing better diagnostic and therapeutic agents complying with existing theranostic techniques. Nuclear medicine technique helps to visualize hard-to-diagnose deep-seated bacterial infections using radionuclide-labeled tracer agents. Metronidazole is an antiprotozoal antibiotic that serves as a preeminent anaerobic chemotherapeutic agent. The aim of this study was to develop technetium-99m-labeled metronidazole radiotracer for the detection of deep-seated bacterial infections. Radiosynthesis of 99m Tc-metronidazole was carried by reacting reduced technetium-99m and metronidazole at neutral pH for 30 min. The stannous chloride dihydrate was used as the reducing agent. At optimum radiolabeling conditions, ~ 94% radiochemical was obtained. Quality control analysis was carried out with a chromatographic paper and instant thin-layer chromatographic analysis. The biodistribution study of radiochemical was performed using Escherichia coli bacterial infection-induced rat model. The scintigraphic study was performed using E. coli bacterial infection-induced rabbit model. The results showed promising accumulation at the site of infection and its rapid clearance from the body. The tracer showed target-to-non-target ratio 5.57 ± 0.04 at 1 h post-injection. The results showed that 99m Tc-MNZ has promising potential to accumulate at E. coli bacterial infection that can be used for E. coli infection imaging.

Comparison Study of Two Differently Clicked 18F-Folates—Lipophilicity Plays a Key Role

PubMed Central

Kettenbach, Kathrin; Reffert, Laura M.; Schieferstein, Hanno; Pektor, Stefanie; Eckert, Raphael; Miederer, Matthias; Rösch, Frank

2018-01-01

Within the last decade, several folate-based radiopharmaceuticals for Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) have been evaluated; however, there is still a lack of suitable 18F-folates for clinical PET imaging. Herein, we report the synthesis and evaluation of two novel 18F-folates employing strain-promoted and copper-catalyzed click chemistry. Furthermore, the influence of both click-methods on lipophilicity and pharmacokinetics of the 18F-folates was investigated. 18F-Ala-folate and 18F-DBCO-folate were both stable in human serum albumin. In vitro studies proved their high affinity to the folate receptor (FR). The lipophilic character of the strain-promoted clicked 18F-DBCO-folate (logD = 0.6) contributed to a higher non-specific binding in cell internalization studies. In the following in vivo PET imaging studies, FR-positive tumors could not be visualized in a maximum intensity projection images. Compared with 18F-DBCO-folate, 18F-Ala-folate (logD = −1.4), synthesized by the copper-catalyzed click reaction, exhibited reduced lipophilicity, and as a result an improved in vivo performance and a clear-cut visualization of FR-positive tumors. In view of high radiochemical yield, radiochemical purity and favorable pharmacokinetics, 18F-Ala-folate is expected to be a promising candidate for FR-PET imaging. PMID:29562610

Total Cross Sections as a Surrogate for Neutron Capture: An Opportunity to Accurately Constrain (n,γ) Cross Sections for Nuclides Beyond the Reach of Direct Measurements

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

Koehler, Paul E.

2014-03-05

There are many (n,γ) cross sections of great interest to radiochemical diagnostics and to nuclear astrophysics which are beyond the reach of current measurement techniques, and likely to remain so for the foreseeable future. In contrast, total neutron cross sections currently are feasible for many of these nuclides and provide almost all the information needed to accurately calculate the (n,γ) cross sections via the nuclear statistical model (NSM). I demonstrate this for the case of 151Sm; NSM calculations constrained using average resonance parameters obtained from total cross section measurements made in 1975, are in excellent agreement with recent 151Sm (n,γ)more » measurements across a wide range of energy. Furthermore, I demonstrate through simulations that total cross section measurements can be made at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center for samples as small as 10μg. Samples of this size should be attainable for many nuclides of interest. Finally, I estimate that over half of the radionuclides identified ~20 years ago as having (n,γ) cross sections of importance to s-process nucleosynthesis studies (24/43) and radiochemical diagnostics (11/19), almost none of which have been measured, can be constrained using this technique.« less

Variation across individuals and items determine learning outcomes from fast mapping.

PubMed

Coutanche, Marc N; Koch, Griffin E

2017-11-01

An approach to learning words known as "fast mapping" has been linked to unique neurobiological and behavioral markers in adult humans, including rapid lexical integration. However, the mechanisms supporting fast mapping are still not known. In this study, we sought to help change this by examining factors that modulate learning outcomes. In 90 subjects, we systematically manipulated the typicality of the items used to support fast mapping (foils), and quantified learners' inclination to employ semantic, episodic, and spatial memory through the Survey of Autobiographical Memory (SAM). We asked how these factors affect lexical competition and recognition performance, and then asked how foil typicality and lexical competition are related in an independent dataset. We find that both the typicality of fast mapping foils, and individual differences in how different memory systems are employed, influence lexical competition effects after fast mapping, but not after other learning approaches. Specifically, learning a word through fast mapping with an atypical foil led to lexical competition, while a typical foil led to lexical facilitation. This effect was particularly evident in individuals with a strong tendency to employ semantic memory. We further replicated the relationship between continuous foil atypicality and lexical competition in an independent dataset. These findings suggest that semantic properties of the foils that support fast mapping can influence the degree and nature of subsequent lexical integration. Further, the effects of foils differ based on an individual's tendency to draw-on the semantic memory system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impaired leptin expression and abnormal response to fasting in corticotropin-releasing hormone-deficient mice.

PubMed

Jeong, Kyeong-Hoon; Sakihara, Satoru; Widmaier, Eric P; Majzoub, Joseph A

2004-07-01

Leptin has been postulated to comprise part of an adipostat, whereby during states of excessive energy storage, elevated levels of the hormone prevent further weight gain by inhibiting appetite. A physiological role for leptin in this regard remains unclear because the presence of excessive food, and therefore the need to restrain overeating under natural conditions, is doubtful. We have previously shown that CRH-deficient (Crh(-/-)) mice have glucocorticoid insufficiency and lack the fasting-induced increase in glucocorticoid, a hormone important in stimulating leptin synthesis and secretion. We hypothesized that these mice might have low circulating leptin. Indeed, Crh(-/-) mice exhibited no diurnal variation of leptin, whereas normal littermates showed a clear rhythm, and their leptin levels were lower than their counterparts. A continuous peripheral CRH infusion to Crh(-/-) mice not only restored corticosterone levels, but it also increased leptin expression to normal. Surprisingly, 36 h of fasting elevated leptin levels in Crh(-/-) mice, rather than falling as in normal mice. This abnormal leptin change during fasting in Crh(-/-) mice was corrected by corticosterone replacement. Furthermore, Crh(-/-) mice lost less body weight during 24 h of fasting and ate less food during refeeding than normal littermates. Taken together, we conclude that glucocorticoid insufficiency in Crh(-/-) mice results in impaired leptin production as well as an abnormal increase in leptin during fasting, and propose that the fast-induced physiological reduction in leptin may play an important role to stimulate food intake during the recovery from fasting.

Neutron activation determination of iridium, gold, platinum, and silver in geologic samples

USGS Publications Warehouse

Millard, H.T.

1987-01-01

Low-level methods for the determination of iridium and other noble metals have become increasingly important in recent years due to interest in locating abundance anomalies associated with the Cretaceous and Tertiary (K-T) boundary. Typical iridium anomalies are in the range of 1 to 100 ??g/kg (ppb). Thus methods with detection limits near 0.1 ??g/kg should be adequate to detect K-T boundary anomalies. Radiochemical neutron activation analysis methods continue to be required although instrumental neutron activation analysis techniques employing elaborate gamma-counters are under development. In the procedure developed in this study samples irradiated in the epithermal neutron facility of the U. S. Geological Survey TRIGA Reactor (Denver, Colorado) are treated with a mini-fire assay technique. The iridium, gold, and silver are collected in a 1-gram metallic lead button. Primary contaminants at this stage are arsenic and antimony. These can be removed by heating the button with a mixture of sodium perioxide and sodium hydroxide. The resulting 0.2-gram lead bead is counted in a Compton suppression spectrometer. Carrier yields are determined by reirradiation of the lead beads. This procedure has been applied to the U.S.G.S. Standard Rock PCC-1 and samples from K-T boundary sites in the Western Interior of North America. ?? 1987 Akade??miai Kiado??.

PATHFINDER ATOMIC POWER PLANT TECHNICAL PROGRESS REPORT FOR JULY 1, 1959- SEPTEMBER 30, 1959

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

None

1960-10-31

ABS>Fuel Element Research and Development. Dynamic and static corrosion tests on 8001 Al were completed. Annealmmmg of 1100 cladding on 5083 and M400 cladding on X2219 were tested at 500 deg C, and investigation continued on producing X8101 Al alloy cladding in tube plates by extrusion. Boiler fuel element capsule irradiation tests and subassembly tests are described Heat transfer loop studies and fuel fabrication for the critical facility are reported. Boiler fuel element mechanical design and testing progress is desc ribed. and the superheater fuel element temperature evaluating routine is discussed. Low- enrichment superheater fuel element development included design studiesmore » and stainless steel powder and UO/sub 2/ powder fabrication studies Reactor Mechanical Studies. Research is reported on vessel and structure design, fabrication, and testing, recirculation system design, steam separator tests, and control rod studies. Nuclear Analysis. Reactor physics studies are reported on nuclear constants, baffle plate analysis, comparison of core representations, delayed neutron fraction. and shielding analysis of the reactor building. Reactor and system dynamics and critical experiments were also studied. Chemistry. Progress is reported on recombiner. radioactive gas removal and storage, ion exchanger and radiochemical processing. (For preceding period see ACNP-5915.) (T.R.H.)« less

An Astrobiological View on Sustainable Life

NASA Astrophysics Data System (ADS)

Naganuma, Takeshi

2009-10-01

Life on a global biosphere basis is substantiated in the form of organics and organisms, and defined as the intermediate forms (briefly expressed as CH2O) hovering between the reduced (CH4, methane) and (CO2, carbon dioxide) ends, different from the classical definition of life as a complex organization maintaining ordered structure and information. Both definitions consider sustenance of life meant as protection of life against chaos through an input of external energy. The CH2O-life connection is maintained as long as the supply of H and O lasts, which is in turn are provided by the splitting of the water molecule H2O. Water is split by electricity, as well-known from school-level experiments, and by solar radiation and geothermal heat on a global scale. In other words, the Sun's radiation and the Earth's heat as well as radioactivity split water to supply H and O for continued existence of life on the Earth. These photochemical, radiochemical and geothermal processes have influences on the evolution and current composition of the Earth's atmosphere, compared with those of Venus and Mars, and influences on the planetary climatology. This view of life may be applicable to the "search-for-life in space" and to sustainability assessment of astrobiological habitats.

Removal of 137-Cs from Dissolved Hanford Tank Saltcake by Treatment with IE-911

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

Rapko, Brian M.; Sinkov, Sergei I.; Levitskaia, Tatiana G.

2003-12-09

The U.S. Department of Energy’s Richland Operations Office plans to accelerate the cleanup of the Hanford Site. Testing new technology for the accelerated cleanup will require dissolved saltcake from single-shell tanks. However, the 137Cs will need to be removed from the saltcake to alleviate radiation hazards. A saltcake composite constructed from archived samples from Hanford Site single-shell tanks 241-S-101, 241-S-109, 241-S-110, 241-S-111, 241-U-106, and 241-U-109 was dissolved in water, adjusted to 5 M Na, and transferred from the 222-S Laboratory to the Radiochemical Processing Laboratory (RPL). At the RPL, the approximately 5.5 liters of solution was passed through a 0.2-micronmore » polyethersulfone filter, collected, and homogenized. The filtered solution then was passed through an ion exchange column containing approximately 150 mL IONSIV® IE-911, an engineered form of crystalline silicotitanate available from UOP, at approximately 200 mL/hour in a continuous operation until all of the feed solution had been run through the column. An analysis of the 137Cs concentrations in the initial feed solution and combined column effluent indicates that > 99.999 percent of the Cs in the feed solution was removed by this operation. PNNR« less

Unraveling the metabolic health benefits of fasting related to religious beliefs: A narrative review.

PubMed

Persynaki, Angeliki; Karras, Spyridon; Pichard, Claude

2017-03-01

Periodic fasting, under a religious aspect, has been adopted by humans for centuries as a crucial pathway of spiritual purification. Caloric restriction, with or without exclusion of certain types of food, is often a key component. Fasting varies significantly among different populations according to cultural habits and local climate conditions. Religious fasting in terms of patterns (continuous versus intermittent) and duration can vary from 1 to 200 d; thus, the positive and negative impact on health can be considerable. Advantages of religious fasting are claimed by many but have been explored mainly by a limited number of studies conducted in Buddhist, Christian, or Muslim populations. These trials indicate that religious fasting has beneficial effects on body weight and glycemia, cardiometabolic risk markers, and oxidative stress parameters. Animals exposed to a diet mimicking fasting have demonstrated weight loss as well as lowered plasma levels of glucose, triacylglycerols, and insulin growth factor-1, although lean body mass remained stable. Diabetic mice on repeated intermittent fasting had less insulin resistance that mice fed ad libitum. The long-term significance of such changes on global health remains to be explored. This review summarizes the data available with regard to benefits of fasting followed for religious reasons on human health, body anthropometry, and cardio-metabolic risk markers; aims to bridge the current knowledge gap on available evidence and suggests considerations for the future research agenda. Future studies should explore every type of religious fasting, as well as their consequences in subpopulations such as children, pregnant women, and the elderly, or patients with chronic metabolic diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

Fast food and obesity: a spatial analysis in a large United Kingdom population of children aged 13-15.

PubMed

Fraser, Lorna K; Clarke, Graham P; Cade, Janet E; Edwards, Kimberly L

2012-05-01

The childhood obesity epidemic is a current public health priority in many countries, and the consumption of fast food has been associated with obesity. This study aims to assess the relationship between fast-food consumption and obesity as well as the relationship between fast-food outlet access and consumption in a cohort of United Kingdom teenagers. A weighted accessibility score of the number of fast-food outlets within a 1-km network buffer of the participant's residence at age 13 years was calculated. Geographically weighted regression was used to assess the relationships between fast-food consumption at age 13 years and weight status at ages 13 and 15 years, and separately between fast-food accessibility and consumption. Data were collected from 2004 to 2008. The consumption of fast food was associated with a higher BMI SD score (β=0.08, 95% CI=0.03, 0.14); higher body fat percentage (β=2.06, 95% CI=1.33, 2.79); and increased odds of being obese (OR=1.23, 95% CI=1.02, 1.49). All these relationships were stationary and did not vary over space in the study area. The relationship between the accessibility of outlets and consumption did vary over space, with some areas (more rural areas) showing that increased accessibility was associated with consumption, whereas in some urban areas increased accessibility was associated with lack of consumption. There is continued need for nutritional education regarding fast food, but public health interventions that place restrictions on the location of fast-food outlets may not uniformly decrease consumption. Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Antibiotic-prescribing patterns for Iraqi patients during Ramadan

PubMed Central

Mikhael, Ehab Mudher; Jasim, Ali Lateef

2014-01-01

Background During Ramadan, Muslims fast throughout daylight hours. There is a direct link between fasting and increasing incidence of infections. Antibiotic usage for treatment of infections should be based on accurate diagnosis, with the correct dose and dosing regimen for the shortest period to avoid bacterial resistance. This study aimed to evaluate the practices of physicians in prescribing suitable antibiotics for fasting patients and the compliance of the patients in using such antibiotics at regular intervals. Materials and methods An observational study was carried out during the middle 10 days of Ramadan 2014 in two pharmacies at Baghdad. A total of 34 prescriptions (Rx) for adults who suffered from infections were examined. For each included Rx, the researchers documented the age and sex of the patient, the diagnosis of the case, and the name of the given antibiotic(s) with dose and frequency of usage. A direct interview with the patient was also done, at which each patient was asked about fasting and if he/she would like to continue fasting during the remaining period of Ramadan. The patient was also asked if the physician asked him/her about fasting before writing the Rx. Results More than two-thirds of participating patients were fasting during Ramadan. Antibiotics were prescribed at a higher percentage by dentists and surgeons, for which a single antibiotic with a twice-daily regimen was the most commonly prescribed by physicians for patients during the Ramadan month. Conclusion Physicians fail to take patient fasting status into consideration when prescribing antibiotics for their fasting patients. Antibiotics with a twice-daily regimen are not suitable and best to be avoided for fasting patients in Iraq during Ramadan – especially if it occurs during summer months – to avoid treatment failure and provoking bacterial resistance. PMID:25473271

Proportion of adults fasting for lipid testing relative to guideline changes in Alberta.

PubMed

Ma, Irene; Viczko, Jeannine; Naugler, Christopher

2017-04-01

Guidelines have historically recommended measuring lipid profile tests in a fasting state. However, in April 2011 and 2014, the Canadian city of Calgary and its province of Alberta, respectively, have changed their lipid guidelines to allow testing for individuals in any fasting state; several years prior to the release of the 2016 Canadian Cardiovascular Society and Hypertension Canada guidelines. The purpose of this study was to document the proportion of individuals in Calgary who fasted for a lipid encounter in relation to the change in various guidelines and policies. Counts were collected each month per gender from January 1, 2010 to June 30, 2016 for community-based adults ≥18years old who fasted (≥8h) or did not fast (<8h) for a lipid encounter. During the study period, 793,719 community-based lipid profiles were performed, 590,174 in a fasting state. The proportion of adults who fasted declined from 98.59%±0.379% (mean±SD) in 2010 to 41.65%±1.295% (mean±SD) in 2016. However, a marked decline in the proportion of adults fasting for a lipid encounter was not observed until February 2015, which coincided with the release of Alberta's Toward Optimized Practice Clinical Practice Guidelines. This documentation of individuals fasting for a lipid encounter may assist other jurisdictions in Canada with the new nonfasting lipid guideline changes. We recommend releasing provincial clinical practice guidelines, in addition to laboratory bulletins and continuing medical education presentations, regarding the new nonfasting lipid recommendations in other jurisdictions to ensure community patients are aware of this change. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Fast and slow myosins as markers of muscle injury.

PubMed

Guerrero, M; Guiu-Comadevall, M; Cadefau, J A; Parra, J; Balius, R; Estruch, A; Rodas, G; Bedini, J L; Cussó, R

2008-07-01

The diagnosis of muscular lesions suffered by athletes is usually made by clinical criteria combined with imaging of the lesion (ultrasonography and/or magnetic resonance) and blood tests to detect the presence of non-specific muscle markers. This study was undertaken to evaluate injury to fast and slow-twitch fibres using specific muscle markers for these fibres. Blood samples were obtained from 51 non-sports people and 38 sportsmen with skeletal muscle injury. Western blood analysis was performed to determine fast and slow myosin and creatine kinase (CK) levels. Skeletal muscle damage was diagnosed by physical examination, ultrasonography and magnetic resonance and biochemical markers. The imaging tests were found to be excellent for detecting and confirming grade II and III lesions. However, grade I lesions were often unconfirmed by these techniques. Grade I lesions have higher levels of fast myosin than slow myosin with a very small increase in CK levels. Grade II and III lesions have high values of both fast and slow myosin. The evaluation of fast and slow myosin in the blood 48 h after the lesion occurs is a useful aid for the detection of type I lesions in particular, since fast myosin is an exclusive skeletal muscle marker. The correct diagnosis of grade I lesions can prevent progression of the injury in athletes undergoing continual training sessions and competitions, thus aiding sports physicians in their decision making.

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

Samarel, A.M.; Parmacek, M.S.; Magid, N.M.

To determine the relative importance of protein degradation in the development of starvation-induced cardiac atrophy, in vivo fractional synthetic rates of total cardiac protein, myosin heavy chain, actin, light chain 1, and light chain 2 were measured in fed and fasted rabbits by continuous infusion of (/sup 3/H) leucine. In addition, the rate of left ventricular protein accumulation and loss were assessed in weight-matched control and fasted rabbits. Rates of total cardiac protein degradation were then estimated as the difference between rates of synthesis and growth. Fasting produced left ventricular atrophy by decreasing the rate of left ventricular protein synthesismore » (34.8 +/- 1.4, 27.3 +/- 3.0, and 19.3 +/- 1.2 mg/day of left ventricular protein synthesized for 0-, 3-, and 7-day fasted rabbits, respectively). Inhibition of contractile protein synthesis was evident by significant reductions in the fractional synthetic rates of all myofibrillar protein subunits. Although fractional rates of protein degradation increased significantly within 7 days of fasting, actual amounts of left ventricular protein degraded per day were unaffected. Thus, prolonged fasting profoundly inhibits the synthesis of new cardiac protein, including the major protein constituents of the myofibril. Both this inhibition in new protein synthesis as well as a smaller but significant reduction in the average half-lives of cardiac proteins are responsible for atrophy of the heart in response to fasting.« less

21 CFR 320.27 - Guidelines on the design of a multiple-dose in vivo bioavailability study.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE... subjects in the fasting or nonfasting state, depending upon the conditions reflected in the proposed...

Fixing Flawed Body Parts: Engineering New Tissues and Organs

MedlinePlus

... 2015 Print this issue Fixing Flawed Body Parts Engineering New Tissues and Organs En español Send us ... ones. This type of research is called tissue engineering. Exciting advances continue to emerge in this fast- ...

Hydrogen-Detection Apparatus

NASA Technical Reports Server (NTRS)

Ross, H. Richard; Bourgeois, Chris M.

1995-01-01

Apparatus continuously monitors concentration of hydrogen, at level ranging from few parts per million to several percent, in mixture of gases. Simple and fast, providing high sensitivity and linear response. Used to alert technicians to potentially explosive concentrations of residual hydrogen.

Terahertz transmission properties of silicon wafers using continuous-wave terahertz spectroscopy

NASA Astrophysics Data System (ADS)

Kim, Chihoon; Ahn, Jae Sung; Ji, Taeksoo; Eom, Joo Beom

2017-04-01

We present the spectral properties of Si wafers using continuous-wave terahertz (CW-THz) spectroscopy. By using a tunable laser source and a fixed distributed-feedback laser diode (DFB-LD), a stably tunable beat source for CW-THz spectroscopy system can be implemented. THz radiation is generated in the frequency range of 100 GHz-800 GHz by photomixing in a photoconductive antenna. We also measured CW-THz waveforms by changing the beat frequency and confirmed repeatability through repeated measurement. We calculated the peaks of the THz frequency by taking fast Fourier transforms (FFTs) of measured THz waveforms. The feasibility of CW-THz spectroscopy is demonstrated by the THz spectra of Si wafers with different resistivities, mobilities, and carrier concentrations. The results show that Si wafers with a lower resistivity absorb more THz waves. Thus, we expect our CW-THz system to have the advantage of being able to perform fast non-destructive analysis.

Design of an ultra low power third order continuous time current mode ΣΔ modulator for WLAN applications.

PubMed

Behzadi, Kobra; Baghelani, Masoud

2014-05-01

This paper presents a third order continuous time current mode ΣΔ modulator for WLAN 802.11b standard applications. The proposed circuit utilized feedback architecture with scaled and optimized DAC coefficients. At circuit level, we propose a modified cascade current mirror integrator with reduced input impedance which results in more bandwidth and linearity and hence improves the dynamic range. Also, a very fast and precise novel dynamic latch based current comparator is introduced with low power consumption. This ultra fast comparator facilitates increasing the sampling rate toward GHz frequencies. The modulator exhibits dynamic range of more than 60 dB for 20 MHz signal bandwidth and OSR of 10 while consuming only 914 μW from 1.8 V power supply. The FoM of the modulator is calculated from two different methods, and excellent performance is achieved for proposed modulator.

Design of an ultra low power third order continuous time current mode ΣΔ modulator for WLAN applications

PubMed Central

Behzadi, Kobra; Baghelani, Masoud

2013-01-01

This paper presents a third order continuous time current mode ΣΔ modulator for WLAN 802.11b standard applications. The proposed circuit utilized feedback architecture with scaled and optimized DAC coefficients. At circuit level, we propose a modified cascade current mirror integrator with reduced input impedance which results in more bandwidth and linearity and hence improves the dynamic range. Also, a very fast and precise novel dynamic latch based current comparator is introduced with low power consumption. This ultra fast comparator facilitates increasing the sampling rate toward GHz frequencies. The modulator exhibits dynamic range of more than 60 dB for 20 MHz signal bandwidth and OSR of 10 while consuming only 914 μW from 1.8 V power supply. The FoM of the modulator is calculated from two different methods, and excellent performance is achieved for proposed modulator. PMID:25685504

Thyroid diseases and Ramadan

PubMed Central

Raza, Syed A.; Ishtiaq, Osama; Unnikrishnan, A. G.; Khan, A. K. Azad; Ahmad, Jamal; Ganie, Mohammed A.; Azad, Kishwar; Baruah, Manash; Pathan, Md Faruque

2012-01-01

In the month of Ramadan, patients with thyroid diseases, most of the time, do not need treatment adjustments and can fast safely without any health hazards. Patients with hypothyroidism taking thyroxine can take their tablets on an empty stomach at bedtime instead of half an hour before Sehr. Patients with hyperthyroidism, on methimazole/carbimazole can continue their dose in once or twice daily regimes, while those on propylthiouracil need to be switched. Hyperthyroid patients with severe symptoms should start treatment immediately and can avoid fast for few days after a consultation with their religious scholar. PMID:22837909

A new detector for sub-millisecond EXAFS spectroscopy at the European Synchrotron Radiation Facility.

PubMed

Kantor, Innokenty; Labiche, Jean-Claude; Collet, Emmanuel; Siron, Laurent; Thevenin, Jean-Jacques; Ponchut, Cyril; Borrel, Jacques; Mairs, Trevor; Marini, Carlo; Strohm, Cornelius; Mathon, Olivier; Pascarelli, Sakura

2014-11-01

A new FReLoN (Fast-Readout Low-Noise) high-frame-rate detector adopted for the fast continuous collection of X-ray absorption spectra is presented. The detector is installed on the energy-dispersive X-ray absorption beamline ID24 at the ESRF and is capable of full time-resolved EXAFS spectra collection with over 4 kHz repetition rate and 0.2 ms exposure time. An example of the in situ kinetic study of the high-temperature oxidation of metallic iron is presented.

Consumer Electronics Testing to Fast-Rise EMP (Electromagnetic Pulse) (VEMPS (Vertical Electromagnetic Pulse Simulator) 2 Development)

DTIC Science & Technology

1989-06-01

Fast-Rise EMP ( VEMPS 11 Development) 12. PERSONAL AUTHOR(S) Vincent J. Ellis 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year Mot.Dy...SUBJECT TERMS (Continue on reverse if necessary andJ identity by block nwitib") 09EL 03U SBGR EMP, VEMPS 11, consumer electronics, FEMPS, EMP simulation... VEMPS 11), Because of the unique petrr! ance characteristics of VEMPS 11 and the technological changes In consumer electronics over the past 10 years

Fast and Exact Continuous Collision Detection with Bernstein Sign Classification

PubMed Central

Tang, Min; Tong, Ruofeng; Wang, Zhendong; Manocha, Dinesh

2014-01-01

We present fast algorithms to perform accurate CCD queries between triangulated models. Our formulation uses properties of the Bernstein basis and Bézier curves and reduces the problem to evaluating signs of polynomials. We present a geometrically exact CCD algorithm based on the exact geometric computation paradigm to perform reliable Boolean collision queries. Our algorithm is more than an order of magnitude faster than prior exact algorithms. We evaluate its performance for cloth and FEM simulations on CPUs and GPUs, and highlight the benefits. PMID:25568589

Laser Cutting of Thin Nickel Bellows

NASA Technical Reports Server (NTRS)

Butler, C. L.

1986-01-01

Laser cutting technique produces narrow, precise, fast, and repeatable cuts in thin nickel-allow bellows material. Laser cutting operation uses intense focused beam to melt material and assisting gas to force melted material through part thickness, creating void. When part rotated or moved longitudinally, melting and material removal continuous and creates narrow, fast, precise, and repeatable cut. Technique used to produce cuts of specified depths less than material thickness. Avoids distortion, dents, and nicks produced in delicate materials during lathe trimming operations, which require high cutting-tool pressure and holding-fixture forces.

Control system of an excitation power supply for fast axial flow CO2 lasersupda

NASA Astrophysics Data System (ADS)

Li, Bo; Jia, Xinting; Yuan, Hao; Gao, Yuhu; Wang, Youqing

2009-08-01

A switching power control system of fast axial flow CO2 lasers based on DSP is presented. The key techniques are described in detail, include the control principle, realization method and program design. The experiment showed that the system make the laser discharge stably and work in multi-mode. The discharge current can be adjusted from 3mA to 85mA continuously. 20-2000Hz frequency, 0-100% duty cycle laser pulse is achieved. The power supply can improve the processing efficiency and quality.

Effect of an acute fast on energy compensation and feeding behaviour in lean men and women.

PubMed

Johnstone, A M; Faber, P; Gibney, E R; Elia, M; Horgan, G; Golden, B E; Stubbs, R J

2002-12-01

Humans appear to defend against energy deficit to a greater extent than energy surplus. Severe dietary energy restriction resulting in 5-30% weight loss often leads to hyperphagia and weight regain in lean subjects. However, the period of time over which fasting is often endured in Western society are far shorter, approximately 1-2 days. This study examined how a 36 h fast effected the subsequent day's energy and nutrient intake in a group of 24 healthy, lean men and women. Subjects underwent two 2 day treatments, termed 'fast' and 'maintenance'. During the 'fast' treatment, subjects were fed a maintenance diet on the day prior to the fast (day -1) to prevent overeating. They then consumed non-energy drinks only, from 20:00 h on day -1 to 08:00 h on day 2 (ad libitum feeding day), thus fasting for 36 h. On the 'maintenance' protocol, subjects received a maintenance diet throughout day 1. Throughout day 2 they had ad libitum access to a range of familiar foods, which were the same for both treatments. Body weight, blood glucose and respiratory quotient were used as compliance checks. Hunger was monitored on day's -1, 1 and 2 for the fast treatment only. On day 2, average energy intake was 10.2 vs 12.2 MJ/day (s.e.d. 1.0) on the post-maintenance and post-fast periods, respectively (P=0.049). Subjects altered feeding behaviour, in response to the fast, only at breakfast time, selecting a higher-fat meal (P<0.005). Compared to day -1, motivation to eat was elevated during the fast (P<0.05). This continued until breakfast was consumed during the re-feeding period (day 2), when values then returned to baseline. These data suggest that a 36 h fast, which generated a negative energy balance of approximately 12 MJ, did not induce a powerful, unconditioned stimulus to compensate on the subsequent day.

Are we Aware of what we are, we are what we Eat- An Epidemiological Survey.

PubMed

Kaur, Manpreet; M Hegde, Amitha

2008-09-01

The lure of convenience in addition to good taste gets people to junk food addiction. With the advent of television even in the remotest areas people have become more aware of the fast food items available. Children watch television where fast food continues to dominate the food advertisements viewed by children. The easily available fast food in and around school campus and with little knowledge of the far reaching effects of these food items consumed, children fall an easy prey to junk food. Children are unaware of the food they eat and the effects it has on their growth and development. This survey reflects the large percentageof children who surrender to the temptation junk food consumption with little knowledge of its far sighted effects on their health.

MR-Guided Freehand Biopsy of Liver Lesions With Fast Continuous Imaging Using a 1.0-T Open MRI Scanner: Experience in 50 Patients

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

Fischbach, Frank, E-mail: frank.fischbach@med.ovgu.de; Bunke, Juergen; Thormann, Markus

2011-02-15

The purpose of this study was to assess a new open system with a field-strength of 1.0 T for the feasibility of liver biopsy using the freehand technique with fast continuous imaging. Fifty patients with focal liver lesions measuring 5 to 30 mm in diameter were included in the study. Guidance and monitoring was performed using a 1.0-T open magnetic resonance (MR) scanner (Panorama HFO; Philips Healthcare, Best, The Netherlands). With fast continuous imaging using a T1-weighted (T1W) gradient echo (GRE) sequence after administration of gadolinium (Gd)-EOB-DTPA, the needle was placed into the lesion. An interface for interactive dynamic viewingmore » in two perpendicular planes prevented needle deviations T2-weighted turbo spin echo (TSE) fat-suppressed sequence was added to rule out postinterventional hematoma or biloma. All lesions were visible on the interventional images. Biopsy was technically successful, and solid specimens were obtained in all cases. Forty-six patients showed a histopathologic pattern other than native liver tissue, thus confirming correct position of the needle. Time between determination of the lesion and performance of the control scan was on average 18 min. No major complications were recorded. MR guidance with the new 1-T open system must be considered an attractive alternative for liver punction. An interface for dynamic imaging of needle guidance and T1W-GRE imaging with administration of Gd-EOB-DTPA for contrast enhancement allows the pinpoint puncture of liver lesions.« less

Fast online Monte Carlo-based IMRT planning for the MRI linear accelerator

NASA Astrophysics Data System (ADS)

Bol, G. H.; Hissoiny, S.; Lagendijk, J. J. W.; Raaymakers, B. W.

2012-03-01

The MRI accelerator, a combination of a 6 MV linear accelerator with a 1.5 T MRI, facilitates continuous patient anatomy updates regarding translations, rotations and deformations of targets and organs at risk. Accounting for these demands high speed, online intensity-modulated radiotherapy (IMRT) re-optimization. In this paper, a fast IMRT optimization system is described which combines a GPU-based Monte Carlo dose calculation engine for online beamlet generation and a fast inverse dose optimization algorithm. Tightly conformal IMRT plans are generated for four phantom cases and two clinical cases (cervix and kidney) in the presence of the magnetic fields of 0 and 1.5 T. We show that for the presented cases the beamlet generation and optimization routines are fast enough for online IMRT planning. Furthermore, there is no influence of the magnetic field on plan quality and complexity, and equal optimization constraints at 0 and 1.5 T lead to almost identical dose distributions.

Reconsidering earthquake scaling

USGS Publications Warehouse

Gomberg, Joan S.; Wech, Aaron G.; Creager, Kenneth; Obara, K.; Agnew, Duncan

2016-01-01

The relationship (scaling) between scalar moment, M0, and duration, T, potentially provides key constraints on the physics governing fault slip. The prevailing interpretation of M0-T observations proposes different scaling for fast (earthquakes) and slow (mostly aseismic) slip populations and thus fundamentally different driving mechanisms. We show that a single model of slip events within bounded slip zones may explain nearly all fast and slow slip M0-T observations, and both slip populations have a change in scaling, where the slip area growth changes from 2-D when too small to sense the boundaries to 1-D when large enough to be bounded. We present new fast and slow slip M0-T observations that sample the change in scaling in each population, which are consistent with our interpretation. We suggest that a continuous but bimodal distribution of slip modes exists and M0-T observations alone may not imply a fundamental difference between fast and slow slip.

Be Smart: Antibiotics Will Not Help a Cold or the Flu

MedlinePlus

... What Everyone Should Know What You Can Do Antibiotic Resistance Q&As Fast Facts Antibiotics Quiz Glossary For ... Pharmacists Continuing Education & Curriculum Opportunities Weighing in on Antibiotic Resistance Improving Prescribing Core Elements of Outpatient Antibiotic Stewardship ...

18 F-Labeling of Sensitive Biomolecules for Positron Emission Tomography.

PubMed

Krishnan, Hema S; Ma, Longle; Vasdev, Neil; Liang, Steven H

2017-11-07

Positron emission tomography (PET) imaging study of fluorine-18 labeled biomolecules is an emerging and rapidly growing area for preclinical and clinical research. The present review focuses on recent advances in radiochemical methods for incorporating fluorine-18 into biomolecules via "direct" or "indirect" bioconjugation. Recently developed prosthetic groups and pre-targeting strategies, as well as representative examples in 18 F-labeling of biomolecules in PET imaging research studies are highlighted. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Determination of selected trace elements in foodstuffs and biological materials by destructive neutron activation analysis.

PubMed

Bayat, I; Etehadiyan, M; Ansar, M

1995-01-01

Concentration of trace elements in Nescafé, Fariman sugar, and Sadaf turmeric and mercury content in cancerous blood were determined by radiochemical, neutron activation analysis. By this separation method levels of 110mAg, 198Au, 203Hg, 76Se, 51Cr, 24Na, 42K, 99Mo, 122Sb, 82Br, 59Fe, 60Co were measured without interference in the gamma spectroscopy. A nondestructive method has also been used for the analysis of sodium, potassium, and bromine.

Radiolabeled Exosomes for the Early Detection of Metastases and to Predict Breast Cancer Premetastatic Niche

DTIC Science & Technology

2014-08-01

purification methods such as ultra-centrifugation at 100,000g for 2-3 hours and/or gel filtration on PD-10 columns. Specific Aim 2.2. Iodine - 131 ...with I- 131 was performed 6 5 using the Iodogen method and PIERCE® pre-coated iodination tubes. Na131I of high radiochemical purity was supplied by...hydroxyphenylpropionic acid that serves as free I- 131 scavenger. Unbound I- 131 was removed by size exclusion chromatography on PD-10 columns pre

Nuclear Forensics and Radiochemistry: Fission

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

Rundberg, Robert S.

Radiochemistry has been used to study fission since it’ discovery. Radiochemical methods are used to determine cumulative mass yields. These measurements have led to the two-mode fission hypothesis to model the neutron energy dependence of fission product yields. Fission product yields can be used for the nuclear forensics of nuclear explosions. The mass yield curve depends on both the fuel and the neutron spectrum of a device. Recent studies have shown that the nuclear structure of the compound nucleus can affect the mass yield distribution.

Major and trace element concentrations in samples from 72275 and 72255. [chemical composition of lunar rocks

NASA Technical Reports Server (NTRS)

Haskin, L. A.; Blanchard, D. P.; Korotev, R.; Jacobs, J. W.; Brannon, J. A.; Herrmann, A. G.

1974-01-01

Analytical data have been obtained for Co, Sc, Hf, Zn, Cr, Ga, Rb, Cs, Ni, major elements, and rare earth elements in eight samples from boulder 1. The data for trace elements were obtained by radiochemical neutron activation analysis. Major elements, except Na and Mn, were obtained by atomic absorption spectral photometry. Values for Na and Mn were obtained by neutron activation analysis of the same powder that was later dissolved to provide the atomic absorption analyses.

Use of accelerated helium-3 ions for determining oxygen and carbon impurities in some pure materials

NASA Technical Reports Server (NTRS)

Aleksandrova, G. I.; Borisov, G. I.; Demidov, A. M.; Zakharov, Y. A.; Sukhov, G. V.; Shmanenkova, G. I.; Shchelkova, V. P.

1978-01-01

Methods are developed for the determination of O impurity in Be and Si carbide and concurrent determination of C and O impurities in Si and W by irradiation with accelerated He-3 ions and subsequent activity measurements of C-11 and F-18 formed from C and O with the aid of a gamma-gamma coincidence spectrometer. Techniques for determining O in Ge and Ga arsenide with radiochemical separation of F-18 are also described.

Consequences of electroplated targets on radiopharmaceutical preparations

NASA Astrophysics Data System (ADS)

Finn, R. D.; Tirelli, S.; Sheh, Y.; Knott, A.; Gelbard, A. S.; Larson, S. M.; Dahl, J. R.

1991-05-01

The staff of the cyclotron facility at Memorial Sloan-Kettering Cancer Center is involved in a comprehensive radionuclide preparation program which culminates with the formulation of numerous requested short-lived, positron-emitting radiopharmaceutical agents for clinical investigation. Both the produced radionuclide as well as the final radiolabeled compound are subjected to stringent quality control standards including assays for radiochemical and chemical purity. The subtle chemical consequences resulting from the irradiation of a nickel-plated target for 13N production serve to emphasize some of these potential technical difficulties.

Proceedings of the first ERDA statistical symposium, Los Alamos, NM, November 3--5, 1975. [Sixteen papers

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

Nicholson, W L; Harris, J L

1976-03-01

The First ERDA Statistical Symposium was organized to provide a means for communication among ERDA statisticians, and the sixteen papers presented at the meeting are given. Topics include techniques of numerical analysis used for accelerators, nuclear reactors, skewness and kurtosis statistics, radiochemical spectral analysis, quality control, and other statistics problems. Nine of the papers were previously announced in Nuclear Science Abstracts (NSA), while the remaining seven were abstracted for ERDA Energy Research Abstracts (ERA) and INIS Atomindex. (PMA)

Test chamber for alpha spectrometry

DOEpatents

Larsen, Robert P.

1977-01-01

Alpha emitters for low-level radiochemical analysis by measurement of alpha spectra are positioned precisely with respect to the location of a surface-barrier detector by means of a chamber having a removable threaded planchet holder. A pedestal on the planchet holder holds a specimen in fixed engagement close to the detector. Insertion of the planchet holder establishes an O-ring seal that permits the chamber to be pumped to a desired vacuum. The detector is protected against accidental contact and resulting damage.

Preparation of Radiochemical-Labeled Compounds for the U.S. Army Drug Development Program

DTIC Science & Technology

1992-04-20

hydrochloric acid , b) extraction with ether, c) basification with potassium carbonate, d extraction with ether. 2. The crude product was isolated by...Chloride Fisher A-575 880667 Nethylene Chloride Fisher D-37 913251 Alumina, basic Act.I Woelm B 1385 Ethylene Natheson 08227 Hydrochloric Acid Fisher A...4-14C]WR-242511) and [!6- 14C]ertelinic acid were coupleted. A total of 31 m~i of (414 ]WR-238605 was prepared with specific activity of 21 mCi

Nuclear medicine and imaging research. Quantitative studies in radiopharmaceutical science. Comprehensive progress report, January 1, 1983-June 30, 1985

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

Beck, R.N.; Cooper, M.D.

1985-09-01

This comprehensive report outlines the progress made during the past three years in the areas described below. In all instances, initial studies have been carried out and the technical feasibility of carrying through each study has been demonstrated. The studies described include development of cesium-130 and bromine-75 radioisotope generators, the feasibility of using rubidium-82 as a myocardial imaging agent, and radiochemical preparation of C-11 deoxyglucose. 28 refs. (DT)

A Radiochemical Biotechnological Approach: Preliminary Study of Lactose Uptake Rate by Kefir Cells, Using 14C-labeled Lactose, in Anaerobic Fermentation

NASA Astrophysics Data System (ADS)

Golfinopoulos, A.; Soupioni, M.; Kanellaki, M.; Koutinas, A. A.

2008-08-01

The effect of initial lactose concentration on lactose uptake rate by kefir free cells, during the lactose fermentation, was studied in this work. For the investigation 14C-labelled lactose was used due to the fact that labeled and unlabeled molecules are fermented in the same way. The results illustrated lactose uptake rates are about up to two fold higher at lower initial ∘Bé densities as compared with higher initial ∘Bé densities.

Virtually Instantaneous, Room-temperature [11C]-Cyanation Using Biaryl Phosphine Pd(0) Complexes

PubMed Central

Lee, Hong Geun; Milner, Phillip J.; Placzek, Michael S.; Buchwald, Stephen L.; Hooker, Jacob M.

2015-01-01

A new radiosynthetic protocol for the preparation of [11C]aryl nitriles has been developed. This process is based on the direct reaction of in situ prepared L•Pd(Ar)X complexes (L=biaryl phosphine) with [11C]HCN. The strategy is operationally simple, exhibits a remarkably wide substrate scope with short reaction times, and demonstrates superior reactivity compared to previously reported systems. With this procedure, a variety of [11C]nitrile-containing pharmaceuticals were prepared with high radiochemical efficiency. PMID:25565277

Characterization Results For The 2013 HTF 3H Evaporator Overhead Samples

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

Washington, A. L. II

2013-12-04

This report tabulates the radiochemical analysis of the 3H evaporator overhead sample for {sup 137}Cs, {sup 90}Sr, and {sup 129}I to meet the requirements in the Effluent Treatment Project (ETP) Waste Acceptance Criteria (WAC) (rev. 6). This report identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. All data was found to be within the ETP WAC (rev. 6) specification for the Waste Water Collection Tanks (WWCT).

Characterization Results for the 2014 HTF 3H & 2H Evaporator Overhead Samples

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

Washington, A.

2015-05-11

This report tabulates the radiochemical analysis of the 3H and 2H evaporator overhead samples for 137Cs, 90Sr, and 129I to meet the requirements in the Effluent Treatment Project (ETP) Waste Acceptance Criteria (WAC) (rev. 6). This report identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. All data was found to be within the ETP WAC (rev. 6) specification for the Waste Water Collection Tanks (WWCT).

Operation IVY, Pacific Proving Grounds, November 1952. Project 11.5. Radiobiological Studies at Eniwetok before and after Mike Shot

DTIC Science & Technology

1953-06-01

by Species 4.3.3 Radiochemical Analysis 4.4 Invertebrates 4.4.1 Pretest . 4.4.2 Posttest . 15 16 16 18 19 19 19 19 20 20...with Highest Activity, Pretest 4.7 Frequencies of Invertebrate Ashed-sample Counts by Magnitudes, Pre- anc" Posttest .......... 4.8...JANET) BOGOMBOGO (BELLE) BOGALLUA (ALICE) 0 1 2 3 4 5 - PRETEST STATION • - POSTTEST STATION AOMON (SALLY) BIIJIRI (TILDA) ROJOA (URSULA

4-fluoroalkyl-3-halophenyl nortropanes

DOEpatents

Goodman, Mark M.; Chen, Ping

2002-06-04

A series of compounds in the 4-fluoroalkyl-3-halophenyl nortropanes family are described as diagnostic and therapeutic agents for diseases associated with serotonin transporter dysfunction. These compounds bind to serotonin transporter protein with high affinity and selectivity. The invention provides methods of synthesis which incorporate radioisotopic halogens at a last step which permit high radiochemical yield and maximum usable product life. The radiolabeled compounds of the invention are useful as imaging agents for visualizing the location and density of serotonin transporter by PET and SPECT imaging.

Synthesis of (125) I-lamivudine and (125) I-lamivudine-ursodeoxycholic acid codrug.

PubMed

Motaleb, M A; Abo-Kul, M; Ibrahim, Samy M; Saad, Shokry M; Arafat, Muhammad

2016-09-01

The preparation of (125) I-lamivudine ((125) I-3TC) and (125) I-lamivudine-ursodeoxycholic acid codrug ((125) I-3TC-UDCA), suitable for comparative biodistribution studies, is described. The synthesis of the unlabeled precursor 3TC-UDCA proceeds in an 11.6% yield, and the radiolabelling yields for (125) I-3TC and (125) I-3TC-UDCA were 89 and 92%, respectively. The final products are radiochemically pure (greater than 98%). Copyright © 2016 John Wiley & Sons, Ltd.

Dose-on-demand production of diverse 18F-radiotracers for preclinical applications using a continuous flow microfluidic system.

PubMed

Matesic, Lidia; Kallinen, Annukka; Greguric, Ivan; Pascali, Giancarlo

2017-09-01

The production of 18 F-radiotracers using continuous flow microfluidics is under-utilized due to perceived equipment limitations. We describe the dose-on-demand principle, whereby the back-to-back production of multiple, diverse 18 F-radiotracers can be prepared on the same day, on the same microfluidic system using the same batch of [ 18 F]fluoride, the same microreactor, the same HPLC column and SPE cartridge to obtain a useful production yield. [ 18 F]MEL050, [ 18 F]Fallypride and [ 18 F]PBR111 were radiolabeled with [ 18 F]fluoride using the Advion NanoTek Microfluidic Synthesis System. The outlet of the microreactor was connected to an automated HPLC injector and following the collection of the product, SPE reformulation produced the 18 F-radiotracer in <10% ethanolic saline. A thorough automated cleaning procedure was implemented to ensure no cross-contamination between radiotracer synthesis. The complete productions for [ 18 F]MEL050 and [ 18 F]Fallypride were performed at total flow rates of 20μL/min, resulting in 40±13% and 25±13% RCY respectively. [ 18 F]PBR111 was performed at 200μL/min to obtain 27±8% RCY. Molar activities for each 18 F-radiotracer were >100GBq/μmol and radiochemical purities were >97%, implying that the cleaning procedure was effective. Using the same initial solution of [ 18 F]fluoride, microreactor, HPLC column and SPE cartridge, three diverse 18 F-radiotracers could be produced in yields sufficient for preclinical studies in a back-to-back fashion using a microfluidic system with no detectable cross-contamination. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Biological half-life and organ distribution of [3H]8-arginine vasopressin following administration of vasopressin receptor antagonist OPC-31260.

PubMed

Molnár, Andor H; Varga, Csaba; Janáky, Tamás; Tóth, Gábor; Tóth, Géza; Farkas, Judit; László, Ferenc; László, Ferenc A

2007-06-07

The effects of the antidiuretic (V(2)) non-peptide receptor antagonist OPC-31260 on the plasma vasopressin level and the biological half-life and organ distribution of radiochemically pure, biologically active [(3)H]8-arginine vasopressin [spec. act.: 15.9 mCi/mmol (588 GBq/mmol)] were studied in Wistar rats. The plasma vasopressin level increased significantly throughout the whole experimental period (24 h). There was no change in the fast phase of the curves of total radioactivity disappearance from the plasma after the administration of [(3)H]arginine vasopressin (control: 1.51+/-0.17 min, OPC-31260-treated: 1.42+/-0.12 min, n=10). The fast phase of the disappearance curves of intact [(3)H]arginine vasopressin did not change either following the administration of OPC-31260 in a dose of 30 mg/kg p.o. (control: 1.06+/-0.19 min, OPC-31260-treated: 1.00+/-0.15 min, n=6). The slow phase of the biological half-life, which is characteristic for the examined compound, proved to be significantly longer (total radioactivity control: 9.29+/-0.61 min, OPC-31260-treated: 12.33+/-0.42 min, P<0.05, n=10; [(3)H]arginine vasopressin radioactivity: control: 5.96+/-0.58 min, OPC-31260-treated: 8.90+/-0.37 min, P<0.05, n=6). In the control rats, the radioactivity was accumulated to the greatest extent in the neurohypophysis, adenohypophysis and kidney. Following OPC-31260 administration, significantly more radioactive compounds accumulated in the kidney (control: 0.30+/-0.052 total radioactivity %/100 mg organ weight, OPC-31260-treated: 0.50+/-0.133 total radioactivity %/100 mg organ weight, P<0.05, n=10) and neurohypophysis (control: 0.37+/-0.053 total radioactivity %/100 mg organ weight, OPC-31260-treated: 0.52+/-0.076 total radioactivity %/100 mg organ weight, P<0.05, n=10). Our results permit the conclusion that the antidiuretic antagonist OPC-31260 not only blocks the V(2) receptors, but also increases the biological half-life of vasopressin. The longer biological half-life of vasopressin following OPC-31260 administration may play a role in the elevation of the plasma vasopressin level.

Inter-individual differences in the initial 80 minutes of motor learning of handrim wheelchair propulsion.

PubMed

Vegter, Riemer J K; Lamoth, Claudine J; de Groot, Sonja; Veeger, Dirkjan H E J; van der Woude, Lucas H V

2014-01-01

Handrim wheelchair propulsion is a cyclic skill that needs to be learned during rehabilitation. Yet it is unclear how inter-individual differences in motor learning impact wheelchair propulsion practice. Therefore we studied how early-identified motor learning styles in novice able-bodied participants impact the outcome of a low-intensity wheelchair-practice intervention. Over a 12-minute pre-test, 39 participants were split in two groups based on a relative 10% increase in mechanical efficiency. Following the pretest the participants continued one of four different low-intensity wheelchair practice interventions, yet all performed in the same trial-setup with a total 80-minute dose at 1.11 m/s at 0.20 W/kg. Instead of focusing on the effect of the different interventions, we focused on differences in motor learning between participants over the intervention. Twenty-six participants started the pretest with a lower mechanical efficiency and a less optimal propulsion technique, but showed a fast improvement during the first 12 minutes and this effect continued over the 80 minutes of practice. Eventually these initially fast improvers benefitted more from the given practice indicated by a better propulsion technique (like reduced frequency and increased stroke angle) and a higher mechanical efficiency. The initially fast improvers also had a higher intra-individual variability in the pre and posttest, which possibly relates to the increased motor learning of the initially fast improvers. Further exploration of the common characteristics of different types of learners will help to better tailor rehabilitation to the needs of wheelchair-dependent persons and improve our understanding of cyclic motor learning processes.

Detecting earthquakes over a seismic network using single-station similarity measures

NASA Astrophysics Data System (ADS)

Bergen, Karianne J.; Beroza, Gregory C.

2018-06-01

New blind waveform-similarity-based detection methods, such as Fingerprint and Similarity Thresholding (FAST), have shown promise for detecting weak signals in long-duration, continuous waveform data. While blind detectors are capable of identifying similar or repeating waveforms without templates, they can also be susceptible to false detections due to local correlated noise. In this work, we present a set of three new methods that allow us to extend single-station similarity-based detection over a seismic network; event-pair extraction, pairwise pseudo-association, and event resolution complete a post-processing pipeline that combines single-station similarity measures (e.g. FAST sparse similarity matrix) from each station in a network into a list of candidate events. The core technique, pairwise pseudo-association, leverages the pairwise structure of event detections in its network detection model, which allows it to identify events observed at multiple stations in the network without modeling the expected moveout. Though our approach is general, we apply it to extend FAST over a sparse seismic network. We demonstrate that our network-based extension of FAST is both sensitive and maintains a low false detection rate. As a test case, we apply our approach to 2 weeks of continuous waveform data from five stations during the foreshock sequence prior to the 2014 Mw 8.2 Iquique earthquake. Our method identifies nearly five times as many events as the local seismicity catalogue (including 95 per cent of the catalogue events), and less than 1 per cent of these candidate events are false detections.

Fast-to-slow transformation and nuclear import/export kinetics of the transcription factor NFATc1 during electrostimulation of rabbit muscle cells in culture

PubMed Central

Kubis, Hans-Peter; Scheibe, Renate J; Meißner, Joachim D; Hornung, Gunther; Gros, Gerolf

2002-01-01

Contractile activity imposed by chronic electrical stimulation of a primary skeletal muscle cell culture grown on microcarriers over several days led to an increase of slow myosin heavy chain I (MHCI) and a decrease of fast MHCII expression at mRNA and protein levels, indicating an ongoing fast-to-slow transformation. Only patterns with periods of continuous stimulation of > 5 min in a 45 min cycle were capable of inducing a fibre type transformation, and this was independent of the applied stimulation frequency over the range 1-10 Hz. We have shown before that the calcineurin-NFATc1 signalling pathway is indispensable in mediating MHCI upregulation during fibre type transformation. Therefore, subcellular localization of NFATc1 was studied immunocytochemically. This revealed that only one stimulation train lasting for > 5 min was sufficient to induce nuclear import of this factor, which was about complete after 20 min of continuous stimulation. For both induction of NFATc1 import and MHCI mRNA upregulation, the minimum stimulation interval of > 5 min was sufficient and stimulation frequency was not crucial between 1 and 10 Hz. Repetition of stimulation cycles, with pauses (< 40 min) shorter than the time required for complete export of NFATc1, led to an accumulation of NFATc1 in the nuclei with each cycle and thus to an amplification of the transformation signal during extended periods of electrostimulation. The temporal behaviour of NFATc import/export appears to determine the effectiveness of various electrostimulation protocols in inducing fast-to-slow fibre transformation. PMID:12068044

Trends in exposure to television food advertisements in South Korea.

PubMed

Han, Euna; Powell, Lisa M; Kim, Tae Hyun

2013-03-01

Given the increased concern about the impact of TV food advertisements (ads) on individual food choices, we provide important evidence on TV food ad exposure between 2004 and 2009 in South Korea. We used monthly targeted ratings data by age group as the number of ads seen daily from Korean Nielsen Media Research. We generated six food groups: beverages (milk, soda, fruit drinks, sports/energy drinks, water, coffee/tea products, and other); snacks/sweets (cookies/chips, candy, and chewing gum); fast food (Domino's pizza, Lotteria, McDonald's, Mr. Pizza, Pizza Hut, local chicken and pizza franchises, and other); instant noodle; full-service restaurants; and other. From 2004 to 2009, overall exposure to television food ads fell by 19.0% (from 6.8 to 5.5 ads daily), although exposure to full-service restaurant ads increased over that time period by 45.7%. While fast-food ad exposure fell overall, exposure to ads for local fried chicken franchises nearly doubled, making them the most commonly seen fast-food ads by 2009. Fast-food and instant noodle ads made up larger proportions of total ad exposure in 2009 than in 2004 in all age groups, with the largest increase among adolescents. Beverage ads continue to be the most prevalent food ads seen in South Korea. Differential trends found in exposure across and within food product categories and differences by age groups highlight the need for continued monitoring to help inform the regulatory policy debate on food advertising, particularly with regards to ads directed at children and adolescents. Copyright © 2012 Elsevier Ltd. All rights reserved.

Sustainable Thorium Nuclear Fuel Cycles: A Comparison of Intermediate and Fast Neutron Spectrum Systems

DOE PAGES

Brown, Nicholas R.; Powers, Jeffrey J.; Feng, B.; ...

2015-05-21

This paper presents analyses of possible reactor representations of a nuclear fuel cycle with continuous recycling of thorium and produced uranium (mostly U-233) with thorium-only feed. The analysis was performed in the context of a U.S. Department of Energy effort to develop a compendium of informative nuclear fuel cycle performance data. The objective of this paper is to determine whether intermediate spectrum systems, having a majority of fission events occurring with incident neutron energies between 1 eV and 10 5 eV, perform as well as fast spectrum systems in this fuel cycle. The intermediate spectrum options analyzed include tight latticemore » heavy or light water-cooled reactors, continuously refueled molten salt reactors, and a sodium-cooled reactor with hydride fuel. All options were modeled in reactor physics codes to calculate their lattice physics, spectrum characteristics, and fuel compositions over time. Based on these results, detailed metrics were calculated to compare the fuel cycle performance. These metrics include waste management and resource utilization, and are binned to accommodate uncertainties. The performance of the intermediate systems for this selfsustaining thorium fuel cycle was similar to a representative fast spectrum system. However, the number of fission neutrons emitted per neutron absorbed limits performance in intermediate spectrum systems.« less

Hot atoms in cosmic chemistry.

PubMed

Rossler, K; Jung, H J; Nebeling, B

1984-01-01

High energy chemical reactions and atom molecule interactions might be important for cosmic chemistry with respect to the accelerated species in solar wind, cosmic rays, colliding gas and dust clouds and secondary knock-on particles in solids. "Hot" atoms with energies ranging from a few eV to some MeV can be generated via nuclear reactions and consequent recoil processes. The chemical fate of the radioactive atoms can be followed by radiochemical methods (radio GC or HPLC). Hot atom chemistry may serve for laboratory simulation of the reactions of energetic species with gaseous or solid interstellar matter. Due to the effective measurement of 10(8)-10(10) atoms only it covers a low to medium dose regime and may add to the studies of ion implantation which due to the optical methods applied are necessarily in the high dose regime. Experimental results are given for the systems: C/H2O (gas), C/H2O (solid, 77 K), N/CH4 (solid, 77K) and C/NH3 (solid, 77 K). Nuclear reactions used for the generation of 2 to 3 MeV atoms are: N(p,alpha) 11C, 16O(p,alpha pn) 11C and 12C(d,n) 13N with 8 to 45 MeV protons or deuterons from a cyclotron. Typical reactions products are: CO, CO2, CH4, CH2O, CH3OH, HCOOH, NH3, CH3NH2, cyanamide, formamidine, guanidine etc. Products of hot reactions in solids are more complex than in corresponding gaseous systems, which underlines the importance of solid state reactions for the build-up of precursors for biomolecules in space. As one of the major mechanisms for product formation, the simultaneous or fast consecutive reactions of a hot carbon with two target molecules (reaction complex) is discussed.

Development of an inflammation imaging tracer, 111In-DOTA-DAPTA, targeting chemokine receptor CCR5 and preliminary evaluation in an ApoE-/- atherosclerosis mouse model.

PubMed

Wei, Lihui; Petryk, Julia; Gaudet, Chantal; Kamkar, Maryam; Gan, Wei; Duan, Yin; Ruddy, Terrence D

2018-02-07

Chemokine receptor 5 (CCR5) plays an important role in atherosclerosis. Our objective was to develop a SPECT tracer targeting CCR5 for imaging plaque inflammation by radiolabeling D-Ala-peptide T-amide (DAPTA), a CCR5 antagonist, with 111 In. 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) conjugated DAPTA (DOTA-DAPTA) was labeled with 111 In. Cell uptake studies were conducted in U87-CD4-CCR5 and U87-MG cells. Biodistribution was determined in C57BL/6 mice. Autoradiography, en face and Oil Red O (ORO) imaging studies were performed in ApoE -/- mice. DOTA-DAPTA was radiolabeled with 111 In with high radiochemical purity (> 98%) and specific activity (70 MBq·nmol). 111 In-DOTA-DAPTA exhibited fast blood and renal clearance and high spleen uptake. The U87-CD4-CCR5 cells had significantly higher uptake in comparison to the U87-MG cells. The cell uptake was reduced by three times with DAPTA, indicating the receptor specificity of the uptake. Autoradiographic images showed significantly higher lesion uptake of 111 In-DOTA-DAPTA in ApoE -/- mice than that in C57BL/6 mice. The tracer uptake in 4 month old ApoE -/- high fat diet (HFD) mice with blocking agent was twofold lower than the same mice without the blocking agent, demonstrating the specificity of the tracer for the CCR5 receptor. 111 In-DOTA-DAPTA, specifically targeting chemokine receptor CCR5, is a potential SPECT agent for imaging inflammation in atherosclerosis.

Biodistribution and catabolism of (18)F-labeled neurotensin(8-13) analogs.

PubMed

Bergmann, Ralf; Scheunemann, Matthias; Heichert, Christoph; Mäding, Peter; Wittrisch, Holm; Kretzschmar, Marion; Rodig, Heike; Tourwé, Dirk; Iterbeke, Koen; Chavatte, Kris; Zips, Daniel; Reubi, Jean Claude; Johannsen, Bernd

2002-01-01

4-([(18)F]fluoro)benzoyl-neurotensin(8-13) ((18)FB-Arg(8)-Arg(9)-Pro(10)-Tyr(11)- Ile(12)-Leu(13)-OH, 1) and two analogs stabilized in one and two positions ((18)FB-Arg(8)psi(CH(2)NH)Arg(9)-Pro(10)-Tyr(11)- Ile(12)-Leu(13)-OH, 2, (18)FB-Arg(8)psi(CH(2)NH)Arg(9)-Pro(10)-Tyr(11)-Tle(12)-Leu(13)-OH, 3) were synthesized in a radiochemical yield of 25-36% and a specific activity of 5-15 GBq/mmol. The peptides were evaluated in vitro and in vivo for their potential to image tumors overexpressing neurotensin receptor 1 (NTR1) by positron emission tomography (PET). All analogs exhibited in vitro binding affinity in the low nanomolar range to NTR1-expressing human tumors, measured by quantitative receptor autoradiography, HT-29 and WiDr cells, and to sections of tumors derived from these cell lines in mice. The radiotracers were internalized in the cells in vitro, and the fluorinated peptides were able to mobilize intracellular Ca(2+) of WiDr cells. In in vivo studies in rats and in mice bearing HT-29 cell tumors, only a moderate uptake of the radioligands into the studied tumors was observed, presumed to be due to degradation in vivo and fast elimination by the kidneys. In comparison with the other analogs, the specific tumor uptake expressed as tumor-to-muscle relation was highest for the radioligand 3. The blood clearance of 3 was reduced by co-injection of peptidase inhibitors. The catabolic pathways of the radiofluorinated peptides were elucidated. The results suggest that the high binding affinity to NTR1 and the stabilization against proteolytic degradation are not yet sufficient for tumor imaging by PET.

Comparison of Insulin Pump Therapy and Multiple Daily Injections Insulin Regimen in Patients with Type 1 Diabetes During Ramadan Fasting.

PubMed

Alamoudi, Reem; Alsubaiee, Maram; Alqarni, Ali; Saleh, Yousef; Aljaser, Saleh; Salam, Abdul; Eledrisi, Mohsen

2017-06-01

Fasting Ramadan carries a high risk for patients with type 1 diabetes (T1DM). Data on the optimum insulin regimen in these patients are limited. To compare glucose profiles in patients with T1DM who use continuous subcutaneous insulin infusion (CSII) compared with those who use multiple daily injections (MDI) insulin regimen during Ramadan fast. The primary outcome was rates of hypoglycemia. Other outcomes included glycemic control, number of days needed to break fasting, and acute glycemic complications. Patients with T1DM who were on CSII or MDI and decided to fast Ramadan were recruited. Glucose data collected using self-monitoring of blood glucose (SMBG) and continuous glucose monitoring (CGM) were compared in the two groups, CSII and MDI, and glucose control was assessed by measuring serum fructosamine levels. A total of 156 patients were recruited, 61 on CSII and 95 on MDI. There was no difference in the rate of mild hypoglycemia <4.4 mmol/L (<80 mg/dL) (8.6% ± 6.1% in the CSII group and 9.85% ± 9.34% in the MDI group, P = 0.96). The mean rate of severe hypoglycemia <2.7 mmol/L (<50 mg/dL) was also not different in both groups (0.99% ± 1.7% in the CSII group compared to 1.7% ± 4.7% in the MDI group, P = 0.23). There was no difference in glycemic control as measured by fructosamine levels or the number of days that patients have to stop fasting. Glucose variability was significantly better in CSII group (SMBG; standard deviation [SD] 66.9 ± 15.3 vs. 76.9 ± 29.9, P = 0.02) (CGM; SD 68.1 ± 19.6 vs. 78.7 ± 24.9, P = 0.04). No diabetic ketoacidosis was reported in either group. In patients with T1DM who fast Ramadan, there was no difference in rates of hypoglycemia or hyperglycemia between CSII and MDI. However, CSII was associated with less glucose variability.

Cardiovascular response to short-term fasting in menstrual phases in young women: an observational study.

PubMed

Ohara, Kumiko; Okita, Yoshimitsu; Kouda, Katsuyasu; Mase, Tomoki; Miyawaki, Chiemi; Nakamura, Harunobu

2015-08-28

Menstrual cycle-related symptoms are an important health issue for many women, and some may affect cardiac autonomic regulation. In the present study, we evaluated the cardiovascular and physiological stress response to 12-h short-term fasting in the menstrual phases of healthy young women. We performed a randomized crossover study. Subjects were seven female university students (age: 22.3 ± 1.0 years). The experiments comprised four sessions: meal intake in the follicular phase, meal intake in the luteal phase, fasting in the follicular phase, and fasting in the luteal phase. All subjects participated in a total of four experimental sessions during two successive phases (follicular and luteal phase in the same menstrual cycle, or luteal phase and follicular phase in the next menstrual cycle) according to a randomized crossover design. R-R intervals were continuously recorded before and after meals, and power spectral analysis of heart rate variability was performed. Other physiological data were obtained before and 20, 40, 60, and 80 min after meal intake or after the corresponding time point of meal intake (fasting in the follicular or luteal phase). Heart rate decreased during fasting in the follicular and luteal phases. High frequency power increased during fasting in the follicular and luteal phases. In addition, salivary cortisol concentrations decreased during fasting in the luteal phase. In the present study, short-term fasting resulted in higher parasympathetic activity and lower cortisol levels in the luteal phase in these young women. These results indicate a possibility to produce an anti-stress effect in the luteal phase, which may reduce menstrual symptoms.

High-intensity interval training or continuous training, combined or not with fasting, in obese or overweight women with cardiometabolic risk factors: study protocol for a randomised clinical trial.

PubMed

De Lorenzo, Andrea; Van Bavel, Diogo; de Moraes, Roger; Tibiriça, Eduardo V

2018-04-28

Physical inactivity and increased caloric intake play important roles in the pathophysiology of obesity. Increasing physical activity and modifying eating behaviours are first-line interventions, frequently hampered by lack of time to exercise and difficulties in coping with different diets. High-intensity interval training (HIIT) may be a time-efficient method compared with moderate-intensity continuous training (CT). Conversely, diets with a fasting component may be more effective than other complex and restrictive diets, as it essentially limits caloric intake to a specified period without major diet composition changes. Therefore, the combination of HIIT and fasting may provide incremental benefits in terms of effectiveness and time efficiency in obese and sedentary populations. The aim of this study is to determine the effect of HIIT versus CT, combined or not with fasting, on microcirculatory function, cardiometabolic parameters, anthropometric indices, cardiorespiratory fitness and quality of life in a population of sedentary overweight or obese women with cardiometabolic risk factors. Sedentary women aged 30-50 years, with a body mass index ≥25 kg/m 2 and cardiometabolic risk factors, will be randomised to HIIT performed in the fasting state, HIIT performed in the fed state, CT in the fasting state or CT in the fed state. Cardiometabolic parameters, anthropometric indices, cardiorespiratory fitness, quality of life and microvascular function (cutaneous capillary density and microvascular reactivity evaluated by laser speckle contrast imaging) will be evaluated before initiation of the interventions and 16 weeks thereafter. The trial complies with the Declaration of Helsinki and has been approved by the local ethics committee (Instituto Nacional de Cardiologia, Rio de Janeiro, Brazil). All patients provide written informed consent before enrolment and randomisation. The study's results will be disseminated to the healthcare community by publications and presentations at scientific meetings. NCT03236285. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Do high fasting glucose levels suggest nocturnal hypoglycaemia? The Somogyi effect-more fiction than fact?

PubMed

Choudhary, P; Davies, C; Emery, C J; Heller, S R

2013-08-01

The Somogyi effect postulates that nocturnal hypoglycaemia causes fasting hyperglycaemia attributable to counter-regulatory hormone release. Although most published evidence has failed to support this hypothesis, this concept remains firmly embedded in clinical practice and often prevents patients and professionals from optimizing overnight insulin. Previous observational data found lower fasting glucose was associated with nocturnal hypoglycaemia, but did not assess the probability of infrequent individual episodes of rebound hypoglycaemia. We analysed continuous glucose monitoring data to explore its prevalence. We analysed data from 89 patients with Type 1 diabetes who participated in the UK Hypoglycaemia study. We compared fasting capillary glucose following nights with and without nocturnal hypoglycaemia (sensor glucose < 3.5 mmol/l). Fasting capillary blood glucose was lower after nights with hypoglycaemia than without [5.5 (3.0) vs. 14.5 (4.5) mmol/l, P < 0.0001], and was lower on nights with more severe nocturnal hypoglycaemia [5.5 (3.0) vs. 8.2 (2.3) mmol/l; P = 0.018 on nights with nadir sensor glucose of < 2.2 mmol/l vs. 3.5 mmol/l]. There were only two instances of fasting capillary blood glucose > 10 mmol/l after nocturnal hypoglycaemia, both after likely treatment of the episode. When fasting capillary blood glucose is < 5 mmol/l, there was evidence of nocturnal hypoglycaemia on 94% of nights. Our data indicate that, in clinical practice, the Somogyi effect is rare. Fasting capillary blood glucose ≤ 5 mmol/l appears an important indicator of preceding silent nocturnal hypoglycaemia. © 2013 The Authors. Diabetic Medicine © 2013 Diabetes UK.

Effect of bacterial sepsis on gluconeogenic capacity in the rat

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

Holman, J.M. Jr.; Saba, T.M.

Since sepsis places increased demands on the host for energy and on other substrates for tissue repair and host defense, hepatic gluconeogenesis is critical for the host's adaptation to sepsis. Substrate-stimulated gluconeogenesis (i.e., gluconeogenic capacity) was assessed by the alanine load method in mannoheptulose-pretreated rats made septic by cecal ligation after laparotomy, as well as by cecal ligation and puncture after laparotomy. Fasted rats subjected to laparotomy only (sham-ligated) and fasted, nonoperated rats (controls) were investigated simultaneously. Following an overnight (-18 to 0 hr) fast, nonoperated animals converted 17.9 +/- 1.5% of (/sup 14/C)alanine to (/sup 14/C)glucose. Continued fasting inmore » nonoperated animals resulted in enhanced (P less than 0.05) gluconeogenic capacity (6 hr = 27.2 +/- 3.0%; 24 hr = 26.2 +/- 1.9%; and 48 hr = 28.5 +/- 2.6%) relative to Time 0. Laparotomy alone (sham ligation) delayed the fasting-induced increase (P less than 0.05) in gluconeogenesis capacity (6 hr = 21.1 +/- 1.2%; 24 hr = 18.5 +/- 1.3%; 48 hr = 27.8 +/- 1.0%) relative to Time 0. In contrast, postoperative sepsis produced a sustained depression (P less than 0.05) of gluconeogenic capacity relative to nonoperated sham-ligated controls at 48 hr (cecal ligation, 18.4 +/- 1.4%; and cecal ligation and puncture, 18.8 +/- 1.2%). Thus, (1) fasting enhances hepatic gluconeogenic capacity; (2) surgical trauma transiently blunts the gluconeogenic response to fasting; and (3) sepsis undermines the gluconeogenic response to fasting.« less

Fast food consumption and gestational diabetes incidence in the SUN project.

PubMed

Dominguez, Ligia J; Martínez-González, Miguel A; Basterra-Gortari, Francisco Javier; Gea, Alfredo; Barbagallo, Mario; Bes-Rastrollo, Maira

2014-01-01

Gestational diabetes prevalence is increasing, mostly because obesity among women of reproductive age is continuously escalating. We aimed to investigate the incidence of gestational diabetes according to the consumption of fast food in a cohort of university graduates. The prospective dynamic "Seguimiento Universidad de Navarra" (SUN) cohort included data of 3,048 women initially free of diabetes or previous gestational diabetes who reported at least one pregnancy between December 1999 and March 2011. Fast food consumption was assessed through a validated 136-item semi-quantitative food frequency questionnaire. Fast food was defined as the consumption of hamburgers, sausages, and pizza. Three categories of fast food were established: low (0-3 servings/month), intermediate (>3 servings/month and ≤2 servings/week) and high (>2 servings/week). Non-conditional logistic regression models were used to adjust for potential confounders. We identified 159 incident cases of gestational diabetes during follow-up. After adjusting for age, baseline body mass index, total energy intake, smoking, physical activity, family history of diabetes, cardiovascular disease/hypertension at baseline, parity, adherence to Mediterranean dietary pattern, alcohol intake, fiber intake, and sugar-sweetened soft drinks consumption, fast food consumption was significantly associated with a higher risk of incident gestational diabetes, with multivariate adjusted OR of 1.31 (95% conficence interval [CI]:0.81-2.13) and 1.86 (95% CI: 1.13-3.06) for the intermediate and high categories, respectively, versus the lowest category of baseline fast food consumption (p for linear trend: 0.007). Our results suggest that pre-pregnancy higher consumption of fast food is an independent risk factor for gestational diabetes.

Glycemic Allostasis during Mental Activities on Fasting in Non-alcohol Users and Alcohol Users with Different Durations of Abstinence.

PubMed

Welcome, Mo; Pereverzev, Va

2014-09-01

Glycemic allostasis is the process by which blood glucose stabilization is achieved through the balancing of glucose consumption rate and release into the blood stream under a variety of stressors. This paper reviews findings on the dynamics of glycemic levels during mental activities on fasting in non-alcohol users and alcohol users with different periods of abstinence. Referred articles for this review were searched in the databases of PubMed, Scopus, DOAJ and AJOL. The search was conducted in 2013 between January 20 and July 31. The following keywords were used in the search: alcohol action on glycemia OR brain glucose OR cognitive functions; dynamics of glycemia, dynamics of glycemia during mental activities; dynamics of glycemia on fasting; dynamics of glycemia in non-alcohol users OR alcohol users; glycemic regulation during sobriety. Analysis of the selected articles showed that glycemic allostasis during mental activities on fasting is poorly regulated in alcohol users even after a long duration of sobriety (1-4 weeks after alcohol consumption), compared to non-alcohol users. The major contributor to the maintenance of euglycemia during mental activities after the night's rest (during continuing fast) is gluconeogenesis.

Glycemic Allostasis during Mental Activities on Fasting in Non-alcohol Users and Alcohol Users with Different Durations of Abstinence

PubMed Central

Welcome, MO; Pereverzev, VA

2014-01-01

Glycemic allostasis is the process by which blood glucose stabilization is achieved through the balancing of glucose consumption rate and release into the blood stream under a variety of stressors. This paper reviews findings on the dynamics of glycemic levels during mental activities on fasting in non-alcohol users and alcohol users with different periods of abstinence. Referred articles for this review were searched in the databases of PubMed, Scopus, DOAJ and AJOL. The search was conducted in 2013 between January 20 and July 31. The following keywords were used in the search: alcohol action on glycemia OR brain glucose OR cognitive functions; dynamics of glycemia, dynamics of glycemia during mental activities; dynamics of glycemia on fasting; dynamics of glycemia in non-alcohol users OR alcohol users; glycemic regulation during sobriety. Analysis of the selected articles showed that glycemic allostasis during mental activities on fasting is poorly regulated in alcohol users even after a long duration of sobriety (1-4 weeks after alcohol consumption), compared to non-alcohol users. The major contributor to the maintenance of euglycemia during mental activities after the night's rest (during continuing fast) is gluconeogenesis. PMID:25364589

Nutritional challenges and health implications of takeaway and fast food.

PubMed

Jaworowska, Agnieszka; Blackham, Toni; Davies, Ian G; Stevenson, Leonard

2013-05-01

Consumption of takeaway and fast food continues to increase in Western societies and is particularly widespread among adolescents. Since food is known to play an important role in both the development and prevention of many diseases, there is no doubt that the observed changes in dietary patterns affect the quality of the diet as well as public health. The present review examines the nutritional characteristics of takeaway and fast food items, including their energy density, total fat, and saturated and trans fatty acid content. It also reports on the association between the consumption of such foods and health outcomes. While the available evidence suggests the nutrient profiles of takeaway and fast foods may contribute to a variety of negative health outcomes, findings on the specific effects of their consumption on health are currently limited and, in recent years, changes have been taking place that are designed to improve them. Therefore, more studies should be directed at gaining a firmer understanding of the nutrition and health consequences of eating takeaway and fast foods and determining the best strategy to reduce any negative impact their consumption may have on public health. © 2013 International Life Sciences Institute.

Thorium Fuel Cycle Option Screening in the United States

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

Taiwo, Temitope A.; Kim, Taek K.; Wigeland, Roald A.

2016-05-01

As part of a nuclear fuel cycle Evaluation and Screening (E&S) study, a wide-range of thorium fuel cycle options were evaluated and their performance characteristics and challenges to implementation were compared to those of other nuclear fuel cycle options based on criteria specified by the Nuclear Energy Office of the U.S. Department of Energy (DOE). The evaluated nuclear fuel cycles included the once-through, limited, and continuous recycle options using critical or externally-driven nuclear energy systems. The E&S study found that the continuous recycle of 233U/Th in fuel cycles using either thermal or fast reactors is an attractive promising fuel cyclemore » option with high effective fuel resource utilization and low waste generation, but did not perform quite as well as the continuous recycle of Pu/U using a fast critical system, which was identified as one of the most promising fuel cycle options in the E&S study. This is because compared to their uranium counterparts the thorium-based systems tended to have higher radioactivity in the short term (about 100 years post irradiation) because of differences in the fission product yield curves, and in the long term (100,000 years post irradiation) because of the decay of 233U and daughters, and because of higher mass flow rates due to lower discharge burnups. Some of the thorium-based systems also require enriched uranium support, which tends to be detrimental to resource utilization and waste generation metrics. Finally, similar to the need for developing recycle fuel fabrication, fuels separations and fast reactors for the most promising options using Pu/U recycle, the future thorium-based fuel cycle options with continuous recycle would also require such capabilities, although their deployment challenges are expected to be higher since such facilities have not been developed in the past to a comparable level of maturity for Th-based systems.« less

21 CFR 320.26 - Guidelines on the design of a single-dose in vivo bioavailability or bioequivalence study.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE... test product and the reference material should be administered to subjects in the fasting state, unless...

Talking about a (business continuity) revolution: Why best practices are wrong and possible solutions for getting them right.

PubMed

Armour, Mark

The business continuity profession has been following a methodology that has barely evolved since its inception. Unfortunately, the stodgy, labour-intensive practices of the past are poorly suited to today's fast-paced and ever-changing work environments. Proposed herein is a new approach to the discipline. Just as agile methodology revolutionised project management, new tactics in preparedness can drastically change how this profession is practised. That is the hope. If there is to be any significant change in business continuity ahead, it may just take a revolution.

Reasoning with Vectors: A Continuous Model for Fast Robust Inference.

PubMed

Widdows, Dominic; Cohen, Trevor

2015-10-01

This paper describes the use of continuous vector space models for reasoning with a formal knowledge base. The practical significance of these models is that they support fast, approximate but robust inference and hypothesis generation, which is complementary to the slow, exact, but sometimes brittle behavior of more traditional deduction engines such as theorem provers. The paper explains the way logical connectives can be used in semantic vector models, and summarizes the development of Predication-based Semantic Indexing, which involves the use of Vector Symbolic Architectures to represent the concepts and relationships from a knowledge base of subject-predicate-object triples. Experiments show that the use of continuous models for formal reasoning is not only possible, but already demonstrably effective for some recognized informatics tasks, and showing promise in other traditional problem areas. Examples described in this paper include: predicting new uses for existing drugs in biomedical informatics; removing unwanted meanings from search results in information retrieval and concept navigation; type-inference from attributes; comparing words based on their orthography; and representing tabular data, including modelling numerical values. The algorithms and techniques described in this paper are all publicly released and freely available in the Semantic Vectors open-source software package.

Reasoning with Vectors: A Continuous Model for Fast Robust Inference

PubMed Central

Widdows, Dominic; Cohen, Trevor

2015-01-01

This paper describes the use of continuous vector space models for reasoning with a formal knowledge base. The practical significance of these models is that they support fast, approximate but robust inference and hypothesis generation, which is complementary to the slow, exact, but sometimes brittle behavior of more traditional deduction engines such as theorem provers. The paper explains the way logical connectives can be used in semantic vector models, and summarizes the development of Predication-based Semantic Indexing, which involves the use of Vector Symbolic Architectures to represent the concepts and relationships from a knowledge base of subject-predicate-object triples. Experiments show that the use of continuous models for formal reasoning is not only possible, but already demonstrably effective for some recognized informatics tasks, and showing promise in other traditional problem areas. Examples described in this paper include: predicting new uses for existing drugs in biomedical informatics; removing unwanted meanings from search results in information retrieval and concept navigation; type-inference from attributes; comparing words based on their orthography; and representing tabular data, including modelling numerical values. The algorithms and techniques described in this paper are all publicly released and freely available in the Semantic Vectors open-source software package.1 PMID:26582967

[Nocturnal continuous subcutaneous insulin infusion--a therapeutic possibility in labile type I diabetes under exceptional conditions].

PubMed

Bruns, W; Steinborn, F; Menzel, R; Staritz, B; Bibergeil, H

1990-03-15

The whole-day continuous subcutaneous insulin infusion (CSII) with portable pumps in daily blood glucose autocontrol guarantees a more stabile and favourable glycaemia than multiple injections in labile type I diabetics. The success is mainly to be traced back to the continuous replacement of the basal secretion, particularly to the nocturnal fasting phase. In this study the effect on the glycaemia is investigated with exclusively nocturnal administration of the CSII under maintenance of multiple insulin injections during this day. In a group of 18 type I diabetics the nocturnal CSII in comparison to intermediate insulin administrations in the evening led to a significant improvement of glycaemia (p less than 0.01), in particular to the decrease of the fasting blood sugars (p less than 0.05). In two casuistic observations in comparison to all the other conventional methods for the compensation of the nocturnal glycaemia (depot insulin, nocturnal injection of normal insulin) the nocturnal CSII proved to be superior. Therefore, the nocturnal CSII is an--though more rarely to be used--alternative, which may be taken into consideration, of a whole-day CSII is temporarily unwished for.

[Diabetes and fasting during Ramadan. A observational study among Turkish immigrants in Belgium].

PubMed

Peeters, B; Mehuys, E; Van Tongelen, I; Van Bever, E; Bultereys, L; Avonts, D; Yildiz, G; Remon, J P; Boussery, K

2013-03-01

To investigate (i) Ramadan participation, (ii) provision of Ramadan related advice by healthcare providers (iii) medication use during Ramadan fasting among Turkish migrants with diabetes in Belgium. This pilot observational study was conducted among a convenience sample of 52 Turkish migrants with diabetes in Belgium. Two questionnaires collected information on socio-demographic characteristics, diabetes related characteristics, current hypoglycaemic medication with dosing regimen, participation in the past Ramadan, reasons for (non)participation, use of hypoglycaemic medication during the past Ramadan, advice from their healthcare providers about fasting during Ramadan and follow up of this advice. Sixteen patients (31%) had fasted during the past Ramadan. Main reason for Ramadan participation was reinforcement of faith (12/15), while the main reason for non participation was having diabetes (34/36). About 56% of the study population had received recommendations from their healthcare provider(s) about fasting and diabetes during Ramadan. The most commonly provided advice was not to participate in Ramadan, followed by modification of drug therapy. Only 3 patients ignored the advice of their healthcare professionals. In addition, only 60% of those who actually fasted received recommendations about intake of diabetes medication during the ramadan. Most fasters continued their medication dose unchanged (87% of OHA users and 80% of the insulin users). This pilot study found a low prevalence of Ramadan fasting among Turkish migrants with diabetes in Belgium. We also found that provision of advice by healthcare providers could be improved. Larger scale studies are warranted to confirm these findings.

Balance and gait in children with dyslexia.

PubMed

Moe-Nilssen, Rolf; Helbostad, Jorunn L; Talcott, Joel B; Toennessen, Finn Egil

2003-05-01

Tests of postural stability have provided some evidence of a link between deficits in gross motor skills and developmental dyslexia. The ordinal-level scales used previously, however, have limited measurement sensitivity, and no studies have investigated motor performance during walking in participants with dyslexia. The purpose of this study was to investigate if continuous-scaled measures of standing balance and gait could discriminate between groups of impaired and normal readers when investigators were blind to group membership during testing. Children with dyslexia ( n=22) and controls ( n=18), aged 10-12 years, performed walking tests at four different speeds (slow-preferred-fast-very fast) on an even and an uneven surface, and tests of unperturbed and perturbed body sway during standing. Body movements were registered by a triaxial accelerometer over the lower trunk, and measures of reaction time, body sway, walking speed, step length and cadence were calculated. Results were controlled for gender differences. Tests of standing balance with eyes closed did not discriminate between groups. All unperturbed standing tests with eyes open showed significant group differences ( P<0.05) and classified correctly 70-77.5% of the subjects into their respective groups. Mean walking speed during very fast walking on both flat and uneven surface was > or =0.2 m/s ( P< or =0.01) faster for controls than for the group with dyslexia. This test classified 77.5% and 85% of the subjects correctly on flat and uneven surface, respectively. Cadence at preferred or very fast speed did not differ statistically between groups, but revealed significant group differences when all subjects were compared at a normalised walking speed ( P< or =0.04). Very fast walking speed as well as cadence at a normalised speed discriminated better between groups when subjects were walking on an uneven surface compared to a flat floor. Continuous-scaled walking tests performed in field settings may be suitable for motor skill assessment as a component of a screening tool for developmental dyslexia.

Design of extraction system in BRing at HIAF

NASA Astrophysics Data System (ADS)

Ruan, Shuang; Yang, Jiancheng; Zhang, Jinquan; Shen, Guodong; Ren, Hang; Liu, Jie; Shangguan, Jingbing; Zhang, Xiaoying; Zhang, Jingjing; Mao, Lijun; Sheng, Lina; Yin, Dayu; Wang, Geng; Wu, Bo; Yao, Liping; Tang, Meitang; Cai, Fucheng; Chen, Xiaoqiang

2018-06-01

The Booster Ring (BRing), which is the key part of HIAF (High Intensity heavy ion Accelerator Facility) complex at IMP (Institute of Modern Physics, Chinese Academy of Sciences), can provide uranium (A / q = 7) beam with a wide extraction energy range of 200-800 MeV/u. To fulfill a flexible beam extraction for multi-purpose experiments, both fast and slow extraction systems will be accommodated in the BRing. The fast extraction system is used for extracting short bunched beam horizontally in single-turn. The slow extraction system is used to provide quasi-continuous beam by the third order resonance and RF-knockout scheme. To achieve a compact structure, the two extraction systems are designed to share the same extraction channel. The general design of the fast and slow extraction systems and simulation results are discussed in this paper.

An Update on Ethanol Production and Utilization in Thailand

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

Bloyd, Cary N.

Thailand has continued to promote domestic biofuel utilization. Production and consumption of biofuel in Thailand have continued to increase at a fast rate due to aggressive policies of the Thai government in reducing foreign oil import and increasing domestic renewable energy utilization. This paper focuses on ethanol production and consumption, and the use of gasohol in Thailand. The paper is an update on the previous paper--Biofuel Infrastructure Development and Utilization in Thailand--in August 2008.

A fast random walk algorithm for computing the pulsed-gradient spin-echo signal in multiscale porous media.

PubMed

Grebenkov, Denis S

2011-02-01

A new method for computing the signal attenuation due to restricted diffusion in a linear magnetic field gradient is proposed. A fast random walk (FRW) algorithm for simulating random trajectories of diffusing spin-bearing particles is combined with gradient encoding. As random moves of a FRW are continuously adapted to local geometrical length scales, the method is efficient for simulating pulsed-gradient spin-echo experiments in hierarchical or multiscale porous media such as concrete, sandstones, sedimentary rocks and, potentially, brain or lungs. Copyright © 2010 Elsevier Inc. All rights reserved.

Hydrodynamic chronoamperometry for probing kinetics of anaerobic microbial metabolism--case study of Faecalibacterium prausnitzii.

PubMed

Prévoteau, Antonin; Geirnaert, Annelies; Arends, Jan B A; Lannebère, Sylvain; Van de Wiele, Tom; Rabaey, Korneel

2015-07-01

Monitoring in vitro the metabolic activity of microorganisms aids bioprocesses and enables better understanding of microbial metabolism. Redox mediators can be used for this purpose via different electrochemical techniques that are either complex or only provide non-continuous data. Hydrodynamic chronoamperometry using a rotating disc electrode (RDE) can alleviate these issues but was seldom used and is poorly characterized. The kinetics of Faecalibacterium prausnitzii A2-165, a beneficial gut microbe, were determined using a RDE with riboflavin as redox probe. This butyrate producer anaerobically ferments glucose and reduces riboflavin whose continuous monitoring on a RDE provided highly accurate kinetic measurements of its metabolism, even at low cell densities. The metabolic reaction rate increased linearly over a broad range of cell concentrations (9 × 10(4) to 5 × 10(7) cells.mL(-1)). Apparent Michaelis-Menten kinetics was observed with respect to riboflavin (KM = 6 μM; kcat = 5.3 × 10(5) s(-1), at 37 °C) and glucose (KM = 6 μM; kcat = 2.4 × 10(5) s(-1)). The short temporal resolution allows continuous monitoring of fast cellular events such as kinetics inhibition with butyrate. Furthermore, we detected for the first time riboflavin reduction by another potential probiotic, Butyricicoccus pullicaecorum. The ability of the RDE for fast, accurate, simple and continuous measurements makes it an ad hoc tool for assessing bioprocesses at high resolution.

Effects of triploidy on growth and protein degradation in skeletal muscle during recovery from feed deprivation in juvenile rainbow trout (Oncorhynchus mykiss).

PubMed

Cleveland, Beth M; Weber, Gregory M

2013-09-01

Identifying physiological differences between diploid and triploid rainbow trout will help define how ploidy affects mechanisms that impact growth and nutrient utilization. Juvenile diploid and triploid female rainbow trout (Oncorhynchus mykiss) were either continually fed or fasted for one week, followed by four weeks of refeeding, and indices of growth and proteolysis-related gene expression in skeletal muscle were measured. Fasting reduced growth, and based on gene expression analysis, increased capacity for protein degradation. Regardless of feeding treatment, triploids displayed slightly greater feed intake and specific growth rates than diploids. Continually fed triploids displayed lower expression of several autophagy-related genes than diploids, suggesting that reduced rates of protein degradation contributed to their faster growth. Reduced expression of ubiquitin ligases fbxo32 and fbxo25 and autophagy-related genes during refeeding implicates reduced proteolysis in recovery growth. At one week of refeeding triploids exhibited greater gains in eviscerated body weight and length, whereas diploids exhibited greater gains in gastrointestinal tract weights. During refeeding two autophagy-related genes, atg4b and lc3b, decreased within one week to continually fed levels in the triploids, but in diploids overshot in expression at one and two weeks of refeeding then rebounding above continually fed levels by week four, suggesting a delayed return to basal levels of proteolysis. Published by Elsevier Inc.

Development of an automated modular system for the synthesis of [11C]acetate.

PubMed

Felicini, Chiara; Någren, Kjell; Berton, Andrea; Pascali, Giancarlo; Salvadori, Piero Alberto

2010-12-01

Carboxylation reactions offer a straightforward method for the synthesis of carbon-11 labelled carboxylic acids. Among these, the preparation of carbon-11 (C)-acetate is receiving increasing attention because of diagnostic applications in oncology in addition to its well-established use as a probe for myocardial oxidative metabolism. Although a number of dedicated modules are commercially available, the development of the synthesis on flexible platforms would be beneficial to widen the number of tracers, in particular for preclinical assessment and testing. In this study, the carboxylation reaction was implemented for the synthesis of sodium 1-[C]acetate after the classic route of carboxylation of methylmagnesium chloride by [C]carbon dioxide, followed by the acidic hydrolysis, purification and sterile filtration. This was performed using a commercially available kit of preassembled hardware units and fully compatible components of radiochemistry automation (VarioSystem). The system proved be to highly versatile and inexpensive and allowed a quick translation of the radiochemistry project into a working system even by less experienced personnel, because of predefined interfaces between electronic parts and operating software (preloaded on a laptop and included in the kit). The automatic module proved to be a simple and reliable system for the production of 1-[C]acetate that was prepared in 24 min (total synthesis time) with stable radiochemical yields (20% nondecay corrected) and high radiochemical purity (>97%). The module is used routinely to produce 1-[C]acetate for preclinical studies and is being implemented for the production of the labelled fatty acids.

Intrinsically Radioactive [64Cu]CuInS/ZnS Quantum Dots for PET and Optical Imaging: Improved Radiochemical Stability and Controllable Cerenkov Luminescence

PubMed Central

2015-01-01

Functionalized quantum dots (QDs) have been widely explored for multimodality bioimaging and proven to be versatile agents. Attaching positron-emitting radioisotopes onto QDs not only endows their positron emission tomography (PET) functionality, but also results in self-illuminating QDs, with no need for an external light source, by Cerenkov resonance energy transfer (CRET). Traditional chelation methods have been used to incorporate the radionuclide, but these methods are compromised by the potential for loss of radionuclide due to cleavage of the linker between particle and chelator, decomplexation of the metal, and possible altered pharmacokinetics of nanomaterials. Herein, we described a straightforward synthesis of intrinsically radioactive [64Cu]CuInS/ZnS QDs by directly incorporating 64Cu into CuInS/ZnS nanostructure with 64CuCl2 as synthesis precursor. The [64Cu]CuInS/ZnS QDs demonstrated excellent radiochemical stability with less than 3% free 64Cu detected even after exposure to serum containing EDTA (5 mM) for 24 h. PEGylation can be achieved in situ during synthesis, and the PEGylated radioactive QDs showed high tumor uptake (10.8% ID/g) in a U87MG mouse xenograft model. CRET efficiency was studied as a function of concentration and 64Cu radioactivity concentration. These [64Cu]CuInS/ZnS QDs were successfully applied as an efficient PET/self-illuminating luminescence in vivo imaging agents. PMID:25549258

Intrinsically radioactive [64Cu]CuInS/ZnS quantum dots for PET and optical imaging: improved radiochemical stability and controllable Cerenkov luminescence.

PubMed

Guo, Weisheng; Sun, Xiaolian; Jacobson, Orit; Yan, Xuefeng; Min, Kyunghyun; Srivatsan, Avinash; Niu, Gang; Kiesewetter, Dale O; Chang, Jin; Chen, Xiaoyuan

2015-01-27

Functionalized quantum dots (QDs) have been widely explored for multimodality bioimaging and proven to be versatile agents. Attaching positron-emitting radioisotopes onto QDs not only endows their positron emission tomography (PET) functionality, but also results in self-illuminating QDs, with no need for an external light source, by Cerenkov resonance energy transfer (CRET). Traditional chelation methods have been used to incorporate the radionuclide, but these methods are compromised by the potential for loss of radionuclide due to cleavage of the linker between particle and chelator, decomplexation of the metal, and possible altered pharmacokinetics of nanomaterials. Herein, we described a straightforward synthesis of intrinsically radioactive [(64)Cu]CuInS/ZnS QDs by directly incorporating (64)Cu into CuInS/ZnS nanostructure with (64)CuCl2 as synthesis precursor. The [(64)Cu]CuInS/ZnS QDs demonstrated excellent radiochemical stability with less than 3% free (64)Cu detected even after exposure to serum containing EDTA (5 mM) for 24 h. PEGylation can be achieved in situ during synthesis, and the PEGylated radioactive QDs showed high tumor uptake (10.8% ID/g) in a U87MG mouse xenograft model. CRET efficiency was studied as a function of concentration and (64)Cu radioactivity concentration. These [(64)Cu]CuInS/ZnS QDs were successfully applied as an efficient PET/self-illuminating luminescence in vivo imaging agents.