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Sample records for extremely short half-life

  1. ESOL facility for the generation and radiochemical separation of short half-life fission products

    International Nuclear Information System (INIS)

    Gehrke, R.J.; Meikrantz, D.H.; Baker, J.D.; Anderl, R.A.; Novick, V.J.; Greenwood, R.C.

    1988-01-01

    A facility has been developed at the Idaho National Engineering Laboratory (INEL) for the generation and rapid radiochemical separation of short half-life mixed fission products. This facility, referred to as the Idaho Elemental Separation On Line (ESOL), consists of electro-plated sources of spontaneously fissioning 252 Cf with a helium jet transport arrangement to continuously deliver short half-life, mixed fission products to the radiochemistry laboratory for rapid, computer controlled, radiochemical separations. 18 refs., 13 figs

  2. Micooprecessor controlled facility for I.N.A.A. using short half life nuclides

    International Nuclear Information System (INIS)

    Bode, P.; Korthoven, P.J.M.; Bruin, M. de

    1986-01-01

    At IRI a new, fully atomated facility for short half life INAA is being developed and installed at the Institute 2 MW reactor. The fast rabbit transfer system is constructed only of plastic and carbonfiber parts, so that rabbit contamination is minimized. This system is automated in such a way that it can operate safely without direct supervision; the sequence of irradiations and measurements is optimized by a computer-program for a given set of samples and analysis procedures. The rabbit system is controlled by an Apple IIe-computer connected to the central PDP 11/44 system of the Radiochemistry department. For a given set of samples and required analysis procedures (irradiation-,decay-, and measurement times) the central computer calculates an optimal sequence of individual actions (transfer from and to the reactor, sample storage of detector) to be carried out by the system. This sequence is loaded into the Apple-computer as a series of commands together with timing information. Actual control of the procedure occurs through the peripheral computer, which makes the system independent of delays or break-downs of the central multi-user computer system. Hardware, software and operating characteristics of the fast rabbit system will be discussed. (author)

  3. The antitumor agent 3-bromopyruvate has a short half-life at physiological conditions.

    Science.gov (United States)

    Glick, Matthew; Biddle, Perry; Jantzi, Josh; Weaver, Samantha; Schirch, Doug

    2014-09-12

    Clinical research is currently exploring the validity of the anti-tumor candidate 3-bromopyruvate (3-BP) as a novel treatment for several types of cancer. However, recent publications have overlooked rarely-cited earlier work about the instability of 3-BP and its decay to 3-hydroxypyruvate (3-HP) which have obvious implications for its mechanism of action against tumors, how it is administered, and for precautions when preparing solutions of 3-BP. This study found the first-order decay rate of 3-BP at physiological temperature and pH has a half-life of only 77 min. Lower buffer pH decreases the decay rate, while choice of buffer and concentration do not affect it. A method for preparing more stable solutions is also reported. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Determination of short half-life elements in biological, foodstuff, and environmental samples qualitatively by neutron activation analysis

    International Nuclear Information System (INIS)

    Syukria Kurniawati; Muhayatun Santoso; Diah Dwiana Lestiani

    2010-01-01

    NAA applications at routine operation power of 15 MW at Multipurpose Reactor GA Siwabessy (MPR-GAS) for sample matrices analysis have been widely applied. However, the results are not optimum for some matrices especially for short half-live elements. Preliminary study of short half-life elements determination in biological, foodstuff, and environmental samples using 1 MW power have been conducted to solve this problem. The samples were irradiated in rabbit system of MPR-GAS for 5 minutes, counted for 200 seconds by HPGe detector, and the spectrum were analyzed further using software Genie 2000 and Bandung NAA Utility. Analysis under 1 MW power on biological and foodstuff samples were capable to detect eight elements: Al, Br, CI, Ca, I, K, Mg, Ti, and Na for biological samples; Al, Br, CI, Ca, I, K, Mg, Mn, and Na for foodstuff samples, while at 15 MW power only three elements (CI, K, Na) were detected. At 1 MW power the counting process is more optimum due to smaller radiation exposure and dead time. For the environmental samples, the number of elements detected by 1 MW and 15 MW powers did not differ significantly. Generally, the results on the three types of samples showed that the elements of short half-life are better detected at 1 MW than that of 15 MW power. Further research needs to be done to obtain the optimum analytical conditions for irradiation and counting time determination. (author)

  5. Innovative methodology for intercomparison of radionuclide calibrators using short half-life in situ prepared radioactive sources

    International Nuclear Information System (INIS)

    Oliveira, P. A.; Santos, J. A. M.

    2014-01-01

    Purpose: An original radionuclide calibrator method for activity determination is presented. The method could be used for intercomparison surveys for short half-life radioactive sources used in Nuclear Medicine, such as 99m Tc or most positron emission tomography radiopharmaceuticals. Methods: By evaluation of the resulting net optical density (netOD) using a standardized scanning method of irradiated Gafchromic XRQA2 film, a comparison of the netOD measurement with a previously determined calibration curve can be made and the difference between the tested radionuclide calibrator and a radionuclide calibrator used as reference device can be calculated. To estimate the total expected measurement uncertainties, a careful analysis of the methodology, for the case of 99m Tc, was performed: reproducibility determination, scanning conditions, and possible fadeout effects. Since every factor of the activity measurement procedure can influence the final result, the method also evaluates correct syringe positioning inside the radionuclide calibrator. Results: As an alternative to using a calibrated source sent to the surveyed site, which requires a relatively long half-life of the nuclide, or sending a portable calibrated radionuclide calibrator, the proposed method uses a source preparedin situ. An indirect activity determination is achieved by the irradiation of a radiochromic film using 99m Tc under strictly controlled conditions, and cumulated activity calculation from the initial activity and total irradiation time. The irradiated Gafchromic film and the irradiator, without the source, can then be sent to a National Metrology Institute for evaluation of the results. Conclusions: The methodology described in this paper showed to have a good potential for accurate (3%) radionuclide calibrators intercomparison studies for 99m Tc between Nuclear Medicine centers without source transfer and can easily be adapted to other short half-life radionuclides

  6. Vitamin E plasma kinetics in swine show low bioavailability and short half-life of -α-tocopheryl acetate.

    Science.gov (United States)

    van Kempen, T A T G; Reijersen, M H; de Bruijn, C; De Smet, S; Michiels, J; Traber, M G; Lauridsen, C

    2016-10-01

    Vitamin E is important for animal production because of its effects on health and product quality, but the amount and form required remains controversial. Our objective was to quantify the absolute bioavailability of oral -α-tocopheryl acetate (α-TAc) in swine (22 ± 1 kg and 8 wk old, fitted with jugular catheters) adapted to a diet supplemented with 75 mg/kg -α-TAc; 75 mg/kg was chosen because this level represents the nonweighted average inclusion level in piglet diets across Western key swine-producing countries. For this, a 350-g test meal (6% fat) was supplied at time 0 containing 75 mg deuterated (D9) -α-TAc to 9 animals, and 8 animals received an intravenous () dose containing deuterated (D6) RRR-α-tocopherol (α-T) at one-eighth the oral dose and a test meal without supplemental vitamin E. Plasma samples (12 to 13 per animal) were obtained at incremental intervals over 75 h for analysis of deuterated α-T using liquid chromatography-tandem mass spectrometry. Surprisingly, the i.v. dose rapidly disappeared from plasma and then reappeared. The half-life for this first peak was only 1.7 ± 0.3 min. The second peak had an appearance rate (Ka) of 0.10 ± 0.06 d and a half-life of 5.9 ± 1.2 h. Oral dosing resulted, after a lag of 56 min, in a Ka of 0.91 ± 0.21 d and a half-life of 2.6 ± 0.8 h. The bioavailability for oral α-TAc was 12.5%, whereas the area under the curve was only 5.4%. This low bioavailability, small area under the curve, and short half-life are likely because of various factors, that is, the use of only 6% fat in the diet, the use of the acetate ester and , and the high dose relative to requirements. In conclusion, i.v. dosed vitamin E shows both a rapid and a very slow pool, whereas orally dosed vitamin E shows a single slow pool. The oral material has a very short half-live (44% of i.v. or 2.6 h), low bioavailability (12.5%), and a very small area under the curve (5.4%), bringing into question the efficacy of typical doses of vitamin

  7. Development of controller of acquisition and sample positioner for activation for use in measurements of short half-life radioisotopes

    International Nuclear Information System (INIS)

    Secco, Marcello

    2016-01-01

    High resolution gamma spectroscopy measurements have several applications. Those involving short half-life radioisotope measurements may present low precision problems when the radioactive source is far from detector end cup and in the very high activity situations also can present accuracy loss due to dead time and pile-up effects. A way to overcome these problems is changing the source detector distance as the activity is decreasing, and thereby maximizing the statistical counting. In the present study, the Controller of Acquisition and Sample Positioner for Activation (CASPA) was developed. It is a low cost and weight device, made with low atomic number materials designed to assist gamma spectroscopy measurements, which is able to control the distance between the source and the detector, even allowing that there is a change of this distance during the measurement process. Because it is automated it optimizes the time of the operator, who has complete freedom to program their routine measurements in the device besides minimizing the radiation dose in the operator. An interface that allow the user control the CASPA system and to program the acquisition system was created. Tests aiming to optimize the operation of CASPA system were carried out and the safety of the CASPA operation was verified, it was not presented any failure during their tests. It was applied the repeatability tests by the acquisition 60 Co standard source and was found that the positioning of automated system has reproduced the results of static system with a 95% of confidence level. (author)

  8. Fast renal trapping of porcine Luteinizing Hormone (pLH shown by 123I-scintigraphic imaging in rats explains its short circulatory half-life

    Directory of Open Access Journals (Sweden)

    Locatelli Alain

    2003-10-01

    Full Text Available Abstract Background Sugar moieties of gonadotropins play no primary role in receptor binding but they strongly affect their circulatory half-life and consequently their in vivo biopotencies. In order to relate more precisely hepatic trapping of these glycoproteic hormones with their circulatory half-life, we undertook a comparative study of the distribution and elimination of porcine LH (pLH and equine CG (eCG which exhibit respectively a short and a long half-life. This was done first by following half-lives of pLH in piglets with hepatic portal circulation shunted or not. It was expected that such a shunt would enhance the short half-life of pLH. Subsequently, scintigraphic imaging of both 123I-pLH and 123I-eCG was performed in intact rats to compare their routes and rates of distribution and elimination. Methods Native pLH or eCG was injected to normal piglets and pLH was tested in liver-shunted anæsthetized piglet. Blood samples were recovered sequentially over one hour time and the hormone concentrations were determined by a specific ELISA method. Scintigraphic imaging of 123I-pLH and 123I-eCG was performed in rats using a OPTI-CGR gamma camera. Results In liver-shunted piglets, the half-life of pLH was found to be as short as in intact piglets (5 min. In the rat, the half-life of pLH was also found to be very short (3–6 min and 123I-pLH was found to accumulate in high quantity in less than 10 min post injection at the level of kidneys but not in the liver. 123I-eCG didn't accumulate in any organ in the rats during the first hour, plasma concentrations of this gonadotropin being still elevated (80% at this time. Conclusion In both the porcine and rat species, the liver is not responsible for the rapid elimination of pLH from the circulation compared to eCG. Our scintigraphic experiments suggest that the very short circulatory half-life of LH is due to rapid renal trapping.

  9. Analytical studies by activation. Part A and B: Counting of short half-life radio-nuclides. Part C: Analytical programs for decay curves

    International Nuclear Information System (INIS)

    Junod, E.

    1966-03-01

    Part A and B: Since a radio-nuclide of short half-life is characterized essentially by the decrease in its activity even while it is being measured, the report begins by recalling the basic relationships linking the half-life the counting time, the counting rate and the number of particles recorded. The second part is devoted to the problem of corrections for counting losses due to the idle period of multichannel analyzers. Exact correction formulae have been drawn up for the case where the short half-life radionuclide is pure or contains only a long half-life radio-nuclide. By comparison, charts have been drawn up showing the approximations given by the so-called 'active time' counting and by the counting involving the real time associated with a measurement of the overall idle period, this latter method proving to be more valid than the former. A method is given for reducing the case of a complex mixture to that of a two-component mixture. Part C: The problems connected with the qualitative and quantitative analysis of the decay curves of a mixture of radioactive sources of which one at least has a short half-life are presented. A mathematical description is given of six basic processes for which some elements of Fortran programs are proposed. Two supplementary programs are drawn up for giving an overall treatment of problems of dosage in activation analysis: one on the basis of a simultaneous irradiation of the sample and of one or several known samples, the other with separate irradiation of the unknown and known samples, a dosimeter (activation, or external) being used for normalizing the irradiation flux conditions. (author) [fr

  10. Propose of a model for dose and hazard calculation due the Rn-222, Rn-220 and its short half-life daugthers inhalation

    International Nuclear Information System (INIS)

    Mauricio, C.L.P.

    1982-01-01

    The compartimental dosimetric model is used to simulate, by computer, the interactions of the inhalated radon atom radiations and its short half-life daugthers with cells. The metabolic trajectory of these radionuclides is described by differential equations of continuous medium dynamics, where the elements transform by radioactive decay. This work permits to determine the individual retenction function, beeing useful in radioprotection routines or emergence situations. The results of internal dosimetry are consistent with the new I.C.R.P. - 32 international recommendations. (L.C.) [pt

  11. Half-life and mass measurement of the short-lived {sup 215}Po isotope (1.78 ms) at the FRS ion catcher

    Energy Technology Data Exchange (ETDEWEB)

    Rink, Ann-Kathrin; Bergmann, Julian; Ebert, Jens; Hornung, Christine; Miskun, Ivan; Reiter, Moritz P. [Justus-Liebig Universitaet Giessen (Germany); Ayet San Andres, Samuel; Dickel, Timo; Plass, Wolfgang R.; Scheidenberger, Christoph [Justus-Liebig Universitaet Giessen (Germany); GSI, Darmstadt (Germany); Geissel, Hans; Purushothaman, Sivaji [GSI, Darmstadt (Germany)

    2016-07-01

    At the Low-Energy Branch (LEB) of the Super-FRS at FAIR, precision experiments with exotic nuclei will be performed using ion traps and lasers. The nuclei will be produced at relativistic energies, slowed down, thermalised in a cryogenic stopping cell (CSC) and made available to various experiments. The thermalisation is a challenging task because of the large energy straggling of the nuclei after production, which requires a stopping cell with large areal densities. Also, the process needs to be performed on a millisecond time scale in order to give access to short-lived nuclides. This method has already been successfully applied at the FRS Ion Catcher at GSI using a prototype CSC. Recently the potential of the method has been demonstrated by the mass and half-life measurement of the {sup 215}Po nuclide with a half-life of 1.78 ms only. The multiple-reflection time-of-flight mass spectrometer at the FRS Ion Catcher has been used to determine the mass to a sub-ppm accuracy and to provide a mass-selected beam for alpha spectroscopy. Furthermore, experiments have been performed with the prototype CSC in order to test novel concepts to be used with the final version of the CSC for the LEB.

  12. The short half-life descendents from radon measured in Sao Jose dos Campos and Cachoeira Paulista, Brazil, and its correlation with meteorological data

    International Nuclear Information System (INIS)

    Andrade Marinho, E.V. de.

    1985-09-01

    The correlations between the activity of the short half-life radon decay products in the low atmosphere and the meterological parameters, measuring the atmospheric polonium 214 are studied. The aerosols were collected on membrane filters and analysed by alpha spectrometry. Measurements have been made in Sao Jose dos Campos and Cachoeira Paulista, in Brazil. At S. Jose dos Campos the influence of the pluviometry on the concentration of atmospheric Po 214 has been analysed, showing that high activity correspond to low pluviometry and inversely, low activities correspond to high pluviometry. At Cachoeira Paulista, the variation in the atmospheric Po 214 activity in corresation with the air stability, measured, showing the accumulation of radioactive aerosols during the greater stability in the the lower atmospheric layers, was studied. (author) [pt

  13. Half-life measurement of 89Rb

    International Nuclear Information System (INIS)

    Guo Xiaoqing; Yuan Daqing; Xu Lijun; Chen Kesheng; Wu Yongle; Zheng Yanming; Yao Shunhe

    2013-01-01

    89 Rb is an important fission product used for monitoring possible release of fission products from fuel element. The half-life is one of important nuclear parameters. The half-life of 89 Rb was determined using reference source method with two sets of HPGe detectors by place-relay way. In reference source method, the ratio of net full- energy peak areas from the measure nuclide and the reference source was used to avoid the count correction caused by dead time and pileup. For the very short half-life of 89 Rb, the half-life iterative method was used in data analysis and the translation method was used in data unification. Finally, the measured half-life of 89 Rb is (14.41±0.04) min. (authors)

  14. Investigation concerning the relative formation rate and half-life time of short-lived nuclides with a fast conveyor tube system

    International Nuclear Information System (INIS)

    Kreiner, H.J.

    1976-01-01

    Since the installation of the 'Ultrafast Rabbit System' at the FRN in end of 1974, some research was started concerning the possibility of neutron activation analysis of short-lived nuclides (0.02 1/2 < 1 s) and measurements of short-lived fission products of U-235 and Pu-239. One of the results of the investigations is a more exact gamma-energy determination of the 0.8 s Cl-38m with 671.33 keV. In NAA it was possible to reach a sensitivity for lead and boron near 2 μg per sample respectively 10 ppm. In measurements of light fission products 0.1 - 8s after a pulse irradiation some differences of the relative formation rate and half-life in the region of A approximately 100 were found in comparison to literature. For example a strong build-up could be seen measuring the gamma-energy of 276.1 keV that belongs to Nb-101. Therefore we suppose the existence of an isomeric state of Nb-101. In comparison to our own results of yield ratio of the Pu- and U-fission products a good agreement with known data was found. Furthermore the measuring method gives the possibility of coordination of unknown gamma-lines to nuclides using the rate of formation, the half-life, the yield ratio between U and Pu and the build-up factor. That could be verified in some cases, e.g. Nb-103 and Sr-96. (author)

  15. Anti-restenotic effect of copper-62 liquid-filled balloon in porcine coronary arteries: novel use of a short half-life positron emitter

    International Nuclear Information System (INIS)

    Chan, Rosanna C.; Lacy, Jeffrey L.; Bhargava, Balram; Collins, Sara D.; Cates, Pamela; Cottin, Yves; Kollum, Marc; Yang, Nathan; Haynes, Neal G.; Martin, Christopher S.; Nayak, Nisha; Vodovotz, Yoram; Kim, Han-Soo; Waksman, Ron

    2000-01-01

    Purpose: To determine the efficacy of the use of copper-62, a positron emitter with a half-life of 9.7 minutes, as an intracoronary brachytherapy (IRBT) source in the prevention of neointima formation (NF) following overstretch balloon injury (BI) in the porcine model. Methods and Materials: Sixteen swine were treated after BI to their left anterior descending (LAD), left circumflex (LCX), and/or right coronary artery (RCA). Twelve of the injured arteries received placebo and 10 received 25 Gy, delivered to 0.5 mm from the surface of the treatment balloon filled with liquid 62 Cu. Dosimetry was based on Monte Carlo calculations. Two weeks after treatment, the animals were sacrificed, and the treated coronaries were perfusion-fixed and stained. Intimal area (IA) and medial fracture length (FL) were analyzed by computer-aided histomorphometry. Results: The ( 62 Zn/ 62 Cu) generator, together with a rapid concentration process, was successful in delivering the short-lived 62 Cu at the high concentration required for intravascular brachytherapy (IVBT). The fracture length in the two groups was similar (2.10 ± 0.57; 2.02 ± 0.77; p = NS). Arteries studied showed significant reduction in NF (IA: 0.23 ± 0.47 mm 2 vs. 1.08 ± 0.57 mm 2 ; p 62 Cu as an IVBT source is safe and feasible. All 16 swine tolerated the treatment well with no radiation-induced side effects or symptoms throughout the 2-week period. The isotope delivered the dose necessary to inhibit NF in the porcine coronary BI model

  16. Half-life determination for 27Mg

    Science.gov (United States)

    Zahn, G. S.; Genezini, F. A.

    2015-07-01

    In this work, the half-life of the short-lived magnesium radionuclide 27Mg was measured by following the activity of samples after they were irradiated in the IEA-R1 reactor. An exponential decay function was then fitted to the results using the counts from a 60Co source as livetime chronometer; the individual half-life values obtained for each irradiation were compiled using both the usual unweighted and σ-2-weighted averages, as well as the robust averages obtained using the Normalized Residuals and the Rajeval techniques. The final halflive values obtained aren't compatible with the ENSDF compilation values, but have a similar uncertainty; analysis of the experimental literature values, all from the 50’s-60’s, show that further measurements should be undertaken in order to achieve a more robust consensus value for this half-life.

  17. Study of niobium isotopes having excess neutrons and a short half-life; Etude des isotopes du niobium excedentaires en neutrons et de courte periode

    Energy Technology Data Exchange (ETDEWEB)

    Huebenthal, K [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1968-02-01

    By irradiating Mo with 14 MeV neutrons isomers have been found for {sup 98}Nb (2.8 s half-life) {sup 99}Nb (9 s) and {sup 100}Nb (2.4 s). No isomer of this type seems to exist for {sup 96}Nb. Rapid separation methods are developed for isolating {sup 98}Zr from fission products, and for separating Zr and Nb. The half-life of {sup 98}Zr is measured (31 s) and the formation of {sup 98}Nb (2.8 s) from {sup 98}Zr (31 s) is shown by milking. Rough {beta} and {gamma} measurements of these nuclei are described. The {gamma} spectrum of {sup 98}Nb (51 mn) is studied with a high-resolution Ge/Li - detector. (authors) [French] Des irradiations des isotopes de molybdene avec des neutrons de 14 MeV ont mis en evidence l'existence des isomeres de {sup 98}Nb (periode 2.8 s) {sup 99}Nb (9 s) et {sup 100}Nb (2.4 s). Pour le {sup 96}Nb un isomere de ce type ne semble pas exister. Des methodes rapides de separation sont mises au point pour isoler le zirconium 98 des produits de fission, et pour separer ensuite le niobium du zirconium. La periode du {sup 98}Zr est de 3l s, et on demontre la formation du {sup 98}Nb (2.8 s) a partir du Zr (31 s). Ces corps sont etudies sommairement en spectroscopie {beta} et {gamma}. Le spectre gamma de {sup 98}Nb (periode 51 mn) est etudie avec un detecteur Ge/Li de haute resolution. (auteurs)

  18. Study of radioactive nuclides of very short half-life produced by fast neutrons; Etude de corps radioactifs a vie tres breve produits par neutrons rapides

    Energy Technology Data Exchange (ETDEWEB)

    Monnand, E [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1965-07-01

    Several radionuclides, already known, with half-lives ranging from 5 10{sup -5} to 1 second were observed by pulsed irradiations of C - Mg - Al - Y - In - Tl - Pb - Bi with 14.3 MeV neutrons. These radionuclides are: {sup 12}B (20 {+-} 0.4 ms) - {sup 24m}Na (20 {+-} 0.6 ms) - {sup 88m1}Y (0.332 {+-} 0.012 ms) - {sup 88m2}Y (14.6 {+-} 0.4 ms) - {sup 114m}In (43.5 {+-} 2 ms) - {sup 202m}Tl (0.570 {+-} 0.010 ms) - {sup 204m}Tl (0.063 {+-} 0.002 ms) - {sup 205m}Pb (5.5 {+-}0.3 ms) - {sup 206m}Pb (0.126 {+-} 0.006 ms) - {sup 207m}Pb (830 {+-} 30 ms) - {sup 208m}Bi (2.56 {+-} 0.1 ms). Their half-life, the {beta} and {gamma} rays energies and the production cross sections were measured. (author) [French] Plusieurs radionucleides deja connus, de periode comprise entre 5 10{sup -5} et 1 seconde ont ete observes par irradiation pulsee avec des neutrons de 14,3 MeV, des elements suivants: C - Mg - Al - Y - In - Tl - Pb - Bi. Ces radionucleides sont: {sup 12}B (20 {+-} 0.4 ms) - {sup 24m}Na (20 {+-} 0.6 ms) - {sup 88m1}Y (0.332 {+-} 0.012 ms) - {sup 88m2}Y (14.6 {+-} 0.4 ms) - {sup 114m}In (43.5 {+-} 2 ms) - {sup 202m}Tl (0.570 {+-} 0.010 ms) - {sup 204m}Tl (0.063 {+-} 0.002 ms) - {sup 205m}Pb (5.5 {+-}0.3 ms) - {sup 206m}Pb (0.126 {+-} 0.006 ms) - {sup 207m}Pb (830 {+-} 30 ms) - {sup 208m}Bi (2.56 {+-} 0.1 ms). Leur periode, l'energie des rayonnements {beta} et {gamma} emis, et la section efficace de production ont ete mesurees. (auteur)

  19. Positive serum specific IgE has a short half-life in patients with penicillin allergy and reversal does not always indicate tolerance.

    Science.gov (United States)

    Hjortlund, Janni; Mortz, Charlotte Gotthard; Stage, Tore Bjerregaard; Skov, Per Stahl; Dahl, Ronald; Bindslev-Jensen, Carsten

    2014-01-01

    The positive and negative predictive values of specific IgE to penicillins are not well established for penicillin hypersensitivity. One reason may be that serum IgE levels to penicillin diminish over time. The objective in this study was to investigate variations in serum half-life (T½) for specific IgE to penicillins (s-IgE) and to evaluate the outcome of penicillin challenges in patients with previous but not present specific IgE to penicillins. Two subgroups were investigated. All included patients had a history of penicillin allergy with reported symptoms such as urticaria/angioedema or unclassified cutaneous rash. T½ of specific IgE to penicillins was calculated based on sera from 29 patients with repeated measurements of s-IgE. Twenty-two patients with a previous positive s-IgE was followed and challenged with penicillin when IgE had become negative. The T½ for s-IgE varied between the 26 patients with decreasing s-IgE from 1.6 months to 76.4 months and 52% had a T½ of less than a year. The three patients with stable and increasing IgE-values showed T½ approaching infinity A total of 29 challenges with β-lactams were performed. Four different patterns were seen when evaluating the clinical reaction to challenge (positive/negative) and post-challenge boost of s-IgE (yes/no). Eight (36.4%) had negative challenge and negative post-challenge s-IgE, eight (36.4%) negative challenge, but positive post-challenge s-IgE levels. 3 (13.6%) had positive challenge and positive post-challenge s-IgE whereas 3 (13.6%) were challenge positive, but had negative post-challenge s-IgE. Specific IgE to penicillins declines over time stressing the importance of a close time relation between diagnostic work-up and clinical reaction. Reversal of previously positive s-IgE may still be associated with positive penicillin challenges and/or re-boostering of s-IgE to positivity.

  20. Fission rates measured using high-energy gamma-rays from short half-life fission products in fresh and spent nuclear fuel

    International Nuclear Information System (INIS)

    Kroehnert, H.

    2011-02-01

    In recent years, higher discharge burn-ups and initial fuel enrichments have led to more and more heterogeneous core configurations in light water reactors (LWRs), especially at the beginning of cycle when fresh fuel assemblies are loaded next to highly burnt ones. As this trend is expected to continue in the future, the Paul Scherrer Institute has, in collaboration with the Swiss Association of Nuclear Utilities, swissnuclear, launched the experimental programme LIFE(at)PROTEUS. The LIFE(at)PROTEUS programme aims to better characterise interfaces between burnt and fresh UO 2 fuel assemblies in modern LWRs. Thereby, a novel experimental database is to be made available for enabling the validation of neutronics calculations of strongly heterogeneous LWR core configurations. During the programme, mixed fresh and highly burnt UO 2 fuel lattices will be investigated in the zero-power research reactor PROTEUS. One of the main types of investigations will be to irradiate the fuel in PROTEUS and measure the resulting fission rate distributions across the interface between fresh and burnt fuel zones. The measurement of fission rates in burnt fuel re-irradiated in a zero-power reactor requires, however, the development of new experimental techniques which are able to discriminate against the high intrinsic activity of the fuel. The principal goal of the present research work has been to develop such a new measurement technique. The selected approach is based on the detection of high-energy gamma-ray lines above the intrinsic background (i.e. above 2200 keV), which are emitted by short-lived fission products freshly created in the fuel. The fission products 88 Kr, 142 La, 138 Cs, 84 Br, 89 Rb, 95 Y, 90m Rb and 90 Rb, with half-lives between 2.6 min and 2.8 h, have been identified as potential candidates. During the present research work, the gamma-ray activity of short-lived fission products has, for the first time, been measured and quantitatively evaluated for re

  1. Fission rates measured using high-energy gamma-rays from short half-life fission products in fresh and spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kroehnert, H.

    2011-02-15

    In recent years, higher discharge burn-ups and initial fuel enrichments have led to more and more heterogeneous core configurations in light water reactors (LWRs), especially at the beginning of cycle when fresh fuel assemblies are loaded next to highly burnt ones. As this trend is expected to continue in the future, the Paul Scherrer Institute has, in collaboration with the Swiss Association of Nuclear Utilities, swissnuclear, launched the experimental programme LIFE(at)PROTEUS. The LIFE(at)PROTEUS programme aims to better characterise interfaces between burnt and fresh UO{sub 2} fuel assemblies in modern LWRs. Thereby, a novel experimental database is to be made available for enabling the validation of neutronics calculations of strongly heterogeneous LWR core configurations. During the programme, mixed fresh and highly burnt UO{sub 2} fuel lattices will be investigated in the zero-power research reactor PROTEUS. One of the main types of investigations will be to irradiate the fuel in PROTEUS and measure the resulting fission rate distributions across the interface between fresh and burnt fuel zones. The measurement of fission rates in burnt fuel re-irradiated in a zero-power reactor requires, however, the development of new experimental techniques which are able to discriminate against the high intrinsic activity of the fuel. The principal goal of the present research work has been to develop such a new measurement technique. The selected approach is based on the detection of high-energy gamma-ray lines above the intrinsic background (i.e. above 2200 keV), which are emitted by short-lived fission products freshly created in the fuel. The fission products {sup 88}Kr, {sup 142}La, {sup 138}Cs, {sup 84}Br, {sup 89}Rb, {sup 95}Y, {sup 90m}Rb and {sup 90}Rb, with half-lives between 2.6 min and 2.8 h, have been identified as potential candidates. During the present research work, the gamma-ray activity of short-lived fission products has, for the first time, been

  2. Methodical Challenges and a Possible Resolution in the Assessment of Receptor Reserve for Adenosine, an Agonist with Short Half-Life

    Directory of Open Access Journals (Sweden)

    Judit Zsuga

    2017-05-01

    Full Text Available The term receptor reserve, first introduced and used in the traditional receptor theory, is an integrative measure of response-inducing ability of the interaction between an agonist and a receptor system (consisting of a receptor and its downstream signaling. The underlying phenomenon, i.e., stimulation of a submaximal fraction of receptors can apparently elicit the maximal effect (in certain cases, provides an opportunity to assess the receptor reserve. However, determining receptor reserve is challenging for agonists with short half-lives, such as adenosine. Although adenosine metabolism can be inhibited several ways (in order to prevent the rapid elimination of adenosine administered to construct concentration–effect (E/c curves for the determination, the consequent accumulation of endogenous adenosine biases the results. To address this problem, we previously proposed a method, by means of which this bias can be mathematically corrected (utilizing a traditional receptor theory-independent approach. In the present investigation, we have offered in silico validation of this method by simulating E/c curves with the use of the operational model of agonism and then by evaluating them using our method. We have found that our method is suitable to reliably assess the receptor reserve for adenosine in our recently published experimental setting, suggesting that it may be capable for a qualitative determination of receptor reserve for rapidly eliminating agonists in general. In addition, we have disclosed a possible interference between FSCPX (8-cyclopentyl-N3-[3-(4-(fluorosulfonylbenzoyloxypropyl]-N1-propylxanthine, an irreversible A1 adenosine receptor antagonist, and NBTI (S-(2-hydroxy-5-nitrobenzyl-6-thioinosine, a nucleoside transport inhibitor, i.e., FSCPX may blunt the effect of NBTI.

  3. Half-life of 230Th

    International Nuclear Information System (INIS)

    Meadows, J.W.; Armani, R.J.; Callis, E.L.; Essling, A.M.

    1980-01-01

    The half-life of 230 Th was measured by the specific activity method. Alpha counting was done in a low geometry counter whose geometry factor was calculated from its dimensions. Sample weights were determined by isotopic dilution. Measurements were made on four isotopic mixtures ranging from 0.383 to 99.52% 230 Th. The half-life is 75381 +- 295 years

  4. Safety objectives and basic design for surface centres for long-term storage of solid radioactive waste with short or medium half-life and low or medium specific activity

    International Nuclear Information System (INIS)

    1984-06-01

    RFS or Regles Fondamentales de Surete (Basic Safety Rules) applicable to certain types of nuclear facilities lay down requirements with which compliance, for the type of facilities and within the scope of application covered by the RFS, is considered to be equivalent to compliance with technical French regulatory practice. The object of the RFS is to take advantage of standardization in the field of safety, while allowing for technical progress in that field. They are designed to enable the operating utility and contractors to know the rules pertaining to various subjects which are considered to be acceptable by the Service Central de Surete des Installations Nucleaires, or the SCSIN (Central Department for the Safety of Nuclear Facilities). These RFS should make safety analysis easier and lead to better understanding between experts and individuals concerned with the problems of nuclear safety. The SCSIN reserves the right to modify, when considered necessary, any RFS and specify, if need be, the terms under which a modification is deemed retroactive. The role of this RFS is to define the safety objectives and the basic design philosophy for surface centres for long-term storage of packages of radioactive waste with short or medium half-life and with low or medium specific activity

  5. Half-life determination of 125I

    International Nuclear Information System (INIS)

    De Felice, P.; Ientile, P.; Zicari, C.

    1990-01-01

    The half-life of 125 I was determined by measuring the activity of an initial 3 kBq source at several times. Over a period of two months, 96 absolute measurements were performed, using the sum-peak method to give a half-life of (59.38±0.03) d. A discussion is presented on the effect of correcting for accidental coincidences on the half-life measurements by comparing the results with and without this correction. (orig.)

  6. Half Life Measurements in 155Gd

    International Nuclear Information System (INIS)

    Malmskog, S.G.

    1966-08-01

    In the literature there exists a definite difference for the half life of the 86.5 keV level in Gd depending on whether 155 Eu or 155 Tb sources have been used. Using a good energy resolution electron-electron coincidence spectrometer and a 155 Eu source, a half life of 6.48 ± 0.26 nsec was obtained for the 86.5 keV level. This is in agreement with the values previously measured with 155 Tb sources. The half life of the 105.4 keV level was measured to be 1.12 ± 0.05 nsec

  7. Half Life Measurements in {sup 155}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G

    1966-08-15

    In the literature there exists a definite difference for the half life of the 86.5 keV level in Gd depending on whether {sup 155}Eu or {sup 155}Tb sources have been used. Using a good energy resolution electron-electron coincidence spectrometer and a {sup 155}Eu source, a half life of 6.48 {+-} 0.26 nsec was obtained for the 86.5 keV level. This is in agreement with the values previously measured with {sup 155}Tb sources. The half life of the 105.4 keV level was measured to be 1.12 {+-} 0.05 nsec.

  8. 243Cm half-life determinaton

    International Nuclear Information System (INIS)

    Timofeev, G.A.; Kalygin, V.V.; Privalova, P.A.

    1986-01-01

    By molar ratios of 243 Cm mixture with 244 Cm and Pu nuclides formed as a result of Cm nuclides α-decay the 243 Cm half-life T α243 is determined. The 244 Cm half-life is measured earlier with high accuracy. The 243 Cm/ 244 Cm ratio measured by means of a mass spectrometer equals 0.989+-0.004. The obtained value T α243 =29.20+-0.14 years

  9. Half-life of 51Mn

    Science.gov (United States)

    Graves, Stephen A.; Ellison, Paul A.; Valdovinos, Hector F.; Barnhart, Todd E.; Nickles, Robert J.; Engle, Jonathan W.

    2017-07-01

    The half-life of 51Mn was measured by serial gamma spectrometry of the 511-keV annihilation photon following decay by β+ emission. Data were collected every 100 seconds for 100,000-230,000 seconds within each measurement (n =4 ). The 511-keV incidence rate was calculated from the 511-keV spectral peak area and count duration, corrected for detector dead time and radioactive decay. Least-squares regression analysis was used to determine the half-life of 51Mn while accounting for the presence of background contaminants, notably 55Co. The result was 45.59 ±0.07 min, which is the highest precision measurement to date and disagrees with the current Nuclear Data Sheets value by over 6 σ .

  10. Half-life of samarium-147

    CERN Document Server

    Kinoshita, N; Nakanishi, T

    2003-01-01

    The alpha-decay half-life of sup 1 sup 4 sup 7 Sm has been reevaluated. Known amounts of natural Sm and an alpha-emitter standard ( sup 2 sup 1 sup 0 Po, sup 2 sup 3 sup 8 U, or sup 2 sup 4 sup 1 Am) were mixed well to prepare thin sources for the simultaneous counting of sup 1 sup 4 sup 7 Sm and the alpha-emitter standard by means of an alpha-spectrometer using a silicon surface barrier detector. The alpha-disintegration rate of known amounts of sup 1 sup 4 sup 7 Sm was determined by reference to the alpha activity of the standard. The source preparation and counting were repeated to establish the reproducibility of the present half-life determination, and supplementary alpha spectrometry was carried out by a liquid-scintillation spectrometer. The arithmetic mean of the experimental half-life values was obtained to be (1.17 +- 0.02) x 10 sup 1 sup 1 y. This value is about 10% longer than the currently adopted value, (1.06 +- 0.02) x 10 sup 1 sup 1 y, and the possible factors for this difference are discussed...

  11. The half-life of 125I

    International Nuclear Information System (INIS)

    Simpson, B.R.S.; Meyer, B.R.

    1989-01-01

    The Bureau International des Poids et Mesures (BIPM) organized an international comparison of activity measurements of a solution of 125 I. The half-life value adopted was 59.5±0.4d. The large uncertainty took account of a recently published value (Schrader, 1986) which is considerably lower than the widely used value of 60.0±0.1d. The present work, which was undertaken at the suggestion of the BIPM, has yielded a value which confirms the lower measurement. (author)

  12. Half-life of Xe120

    Science.gov (United States)

    Phillips, A. A.; Andreoiu, C.; Ball, G. C.; Bandyopadhyay, D.; Behr, J. A.; Chupp, T. E.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hackman, G.; Hayden, M. E.; Hyland, B.; Nuss-Warren, S. R.; Pearson, M. R.; Schumaker, M. A.; Smith, M. B.; Svensson, C. E.; Tardiff, E. R.; Valiente-Dobón, J. J.; Warner, T.

    2006-08-01

    We have measured the half-life of Xe120 using a high-purity germanium (HPGe) detector to monitor the 176, 178, and 762 keV γ rays from Xe120 β+ decay. The result, 46±0.6 min, differs significantly from the value 40±1 min reported by Andersson [Ark. Fys. 28, 37 (1964)]. We have also measured the half-lives of Cs120 and I120 to be 60±0.7 s and 82.1±0.6 min, respectively, both of which are consistent with previous measurements.

  13. Immunological half-life of porcine proinsulin C-peptide

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, H; Horino, M; Matsumura, S [Kawasaki Medical Coll., Kurashiki (Japan). Div. of Endocrinology; Kobayshi, K; Suetsugu, N [Yamaguchi Univ., Ube (Japan). School of Medicine

    1975-11-01

    Immunological half-lifes of injected porcine C-peptide and insulin with RIA were studied and calculated as 9.8 and 8.0 minutes. Higher circulating levels of C-peptide as compared to insulin in normal young swines lead to speculation about a longer half-life of C-peptide. This hypothesis was verified in this study. Immunological half-lifes of porcine proinsulin and insulin in the pig were 20 and 6 minutes, respectively.

  14. Analytical studies by activation. Part A and B: Counting of short half-life radio-nuclides. Part C: Analytical programs for decay curves; Etudes d'analyse par activation. Parties A et B: le comptage des radio-nucleides de periodes courtes. Partie C: programme de depouillement des courbes de decroissance

    Energy Technology Data Exchange (ETDEWEB)

    Junod, E [Commissariat a l' Energie Atomique Grenoble (France). Centre d' Etudes Nucleaires

    1966-03-01

    Part A and B: Since a radio-nuclide of short half-life is characterized essentially by the decrease in its activity even while it is being measured, the report begins by recalling the basic relationships linking the half-life the counting time, the counting rate and the number of particles recorded. The second part is devoted to the problem of corrections for counting losses due to the idle period of multichannel analyzers. Exact correction formulae have been drawn up for the case where the short half-life radionuclide is pure or contains only a long half-life radio-nuclide. By comparison, charts have been drawn up showing the approximations given by the so-called 'active time' counting and by the counting involving the real time associated with a measurement of the overall idle period, this latter method proving to be more valid than the former. A method is given for reducing the case of a complex mixture to that of a two-component mixture. Part C: The problems connected with the qualitative and quantitative analysis of the decay curves of a mixture of radioactive sources of which one at least has a short half-life are presented. A mathematical description is given of six basic processes for which some elements of Fortran programs are proposed. Two supplementary programs are drawn up for giving an overall treatment of problems of dosage in activation analysis: one on the basis of a simultaneous irradiation of the sample and of one or several known samples, the other with separate irradiation of the unknown and known samples, a dosimeter (activation, or external) being used for normalizing the irradiation flux conditions. (author) [French] Parties A et B: Un radionucleide de periode courte etant defini specialement par la decroissance de son activite pendant la duree meme du comptage, on rappelle en premiere partie de ce rapport les relations fondamentales qui lient periode, temps de comptage, taux de comptage et nombre d'impulsions enregistrees. La seconde partie

  15. Experimental study of half-life determinations using 60Co

    International Nuclear Information System (INIS)

    Rutledge, A.R.; Smith, L.V.; Merritt, J.S.

    1983-01-01

    The half-life of 60 Co was determined by two methods, (i) the 4π#betta# ionization chamber method and (ii) the 4π #betta#-#betta# coincidence method. The first is a relative counting method in which the only rate-dependent correction is for background, whereas the second is an 'absolute' counting method which involves several rate-dependent corrections. In addition, various methods of calculation of the results were tested. The half-life values for the two counting systems were in good agreement and the weighted mean value for the half-life of 60 Co was found to be 1925.02+-0.47 d. (orig.)

  16. Tests of a Fast Plastic Scintillator for High-Precision Half-Life Measurements

    Science.gov (United States)

    Laffoley, A. T.; Dunlop, R.; Finlay, P.; Leach, K. G.; Michetti-Wilson, J.; Rand, E. T.; Svensson, C. E.; Grinyer, G. F.; Thomas, J. C.; Ball, G.; Garnsworthy, A. B.; Hackman, G.; Orce, J. N.; Triambak, S.; Williams, S. J.; Andreoiu, C.; Cross, D.

    2013-03-01

    A fast plastic scintillator detector is evaluated for possible use in an ongoing program of high-precision half-life measurements of short lived β emitters. Using data taken at TRI-UMF's Isotope Separator and Accelerator Facility with a radioactive 26Na beam, a detailed investigation of potential systematic effects with this new detector setup is being performed. The technique will then be applied to other β-decay half-life measurements including the superallowed Fermi β emitters 10C, 14O, and T = 1/2 decay of 15O.

  17. A new determination of the 209Po half-life

    International Nuclear Information System (INIS)

    Collé, R; Fitzgerald, R P; Laureano–Perez, L

    2014-01-01

    A substantial 25% error in the then-known and accepted (102 ± 5) year half-life of 209 Po was reported on in 2007. This error was detected from decay data from two separate primary standardizations of a 209 Po solution standard, which were performed approximately 12 years apart. Despite author claims that this observation was not a new half-life determination, it was nevertheless included in subsequent nuclear data evaluations and compilations to obtain a currently tabulated value of (115 ± 13) a, computed from the median and range of the two half-life reports. A third primary standardization on the identical 209 Po solution has since been performed to derive a new half-life value of (125.2 ± 3.3) a. This half-life determination was obtained from 30 distinct data sets over a period of 20.7 years, encompassing over 700 liquid scintillation measurements with nearly 50 counting sources all prepared from the same solution, and as obtained over a very broad range of measurement conditions (composition of cocktails, characteristics of counters, time sequencing) during five periods in 1993, 1994, 2005, and 2013. (paper)

  18. Half-life of 90Sr - measurement and critical review

    International Nuclear Information System (INIS)

    Woods, M.J.; Lucas, S.E.M.

    1996-01-01

    Recent evaluations of the half-life of 90 Sr have demonstrated the variable quality of the available experimental data which has prevented the estimation and adoption of a value that commands confidence. In an attempt to reduce the uncertainty in the half-life to an acceptable level, the decay of a 90 Sr source has been followed for over six years at NPL. The equipment comprised matching, re-entrant, high-pressure ionization chambers and a long-lived reference source to reduce non-random effects. The experimental technique is described together with the statistical procedure used to analyse the measured data. A half-life value was determined together with an estimate of the associated uncertainties. A new evaluation of the 90 Sr half-life has been made, taking account of the new NPL data and other recent measurements. Particular attention has been paid to the experimental techniques used to produce the data and the uncertainties attributed to them. An objective evaluation has been conducted to produce a new recommended half-life value of 10 516 ± 21 days. (orig.)

  19. Development of controller of acquisition and sample positioner for activation for use in measurements of short half-life radioisotopes; Desenvolvimento de dispositivo movimentador automatizado de amostras com vista a aplicacao em medidas de radioisotopos que possuem curto tempo de meia-vida

    Energy Technology Data Exchange (ETDEWEB)

    Secco, Marcello

    2016-08-01

    High resolution gamma spectroscopy measurements have several applications. Those involving short half-life radioisotope measurements may present low precision problems when the radioactive source is far from detector end cup and in the very high activity situations also can present accuracy loss due to dead time and pile-up effects. A way to overcome these problems is changing the source detector distance as the activity is decreasing, and thereby maximizing the statistical counting. In the present study, the Controller of Acquisition and Sample Positioner for Activation (CASPA) was developed. It is a low cost and weight device, made with low atomic number materials designed to assist gamma spectroscopy measurements, which is able to control the distance between the source and the detector, even allowing that there is a change of this distance during the measurement process. Because it is automated it optimizes the time of the operator, who has complete freedom to program their routine measurements in the device besides minimizing the radiation dose in the operator. An interface that allow the user control the CASPA system and to program the acquisition system was created. Tests aiming to optimize the operation of CASPA system were carried out and the safety of the CASPA operation was verified, it was not presented any failure during their tests. It was applied the repeatability tests by the acquisition {sup 60}Co standard source and was found that the positioning of automated system has reproduced the results of static system with a 95% of confidence level. (author)

  20. Determination of the {sup 151}Sm half-life

    Energy Technology Data Exchange (ETDEWEB)

    Be, Marie-Martine; Cassette, Philippe [CEA, LIST, Gif sur Yvette (France). LNE-Laboratoire National Henri Becquerel; Isnard, Helene [CEA-LANIE, Gif sur Yvette (France); and others

    2015-07-01

    New measurements have been undertaken to determine the half-life of {sup 151}Sm. A pure {sup 151}Sm solution was obtained after chemical separation from a samarium solution resulting from the dissolution of an irradiated samarium sample. The concentration of {sup 151}Sm in the solution was measured by mass spectrometry, combined with the isotope dilution technique. The activity of the solution was measured by liquid scintillation counting by six European laboratories as part of an international comparison. These combined results lead to a half-life of T{sub 1/2} = 94.6(6)a.

  1. Calculation of the biological half-life of radioactive isotopes

    International Nuclear Information System (INIS)

    Szabo, S.A.

    1982-01-01

    The biological half-life of 137 Cs and 90 Sr was determined based on K and Ca metabolism and on the considerable chemical similarity of K and Ca, carriers of Cs and Sr, resp. The tsub(1/2)=a/bxln2 formula was used for the calculation, where a is the quantity of the element in question, while b is the daily need of the animal for the given element. The biological half-life for cattle of both 137 Cs and 90 Sr was found to be 30 days, while that for swine 20 days and 35 days respectively. (Sz.J.)

  2. Measurement of the 20F half-life

    Science.gov (United States)

    Hughes, M.; George, E. A.; Naviliat-Cuncic, O.; Voytas, P. A.; Chandavar, S.; Gade, A.; Huyan, X.; Liddick, S. N.; Minamisono, K.; Paulauskas, S. V.; Weisshaar, D.

    2018-05-01

    The half-life of the 20F ground state was measured using a radioactive beam implanted in a plastic scintillator and recording β γ coincidences together with four CsI(Na) detectors. The result, T1 /2=11.0011 (69) stat(30) sys s, is at variance by 17 combined standard deviations with the two most precise results. The present value revives the poor consistency of results for this half-life and calls for a new measurement, with a technique having different sources of systematic effects, to clarify the discrepancy.

  3. On the biological half-life of caesium in pregnant women and infants

    International Nuclear Information System (INIS)

    Rundo, J.; Turner, F.M.

    1992-01-01

    In the 1960s, changes were observed in the levels of 137 Cs in women who were pregnant or who had recently given birth. These were not associated with changes in the rate of fall-out, and were interpreted as the consequences of changes in the biological half-life. It was deduced that the biological half-life of caesium just before parturition averaged 59% of the value (87±33 days) after the birth of the baby; and that there was a step change at parturition. The behaviour of the levels during pregnancy suggested there was a gradual decrease in the biological half-life. Similar measurements were made in very young children. The concentration of the radionuclide in a breast-fed baby was usually a little less than that in the mother, indicating some discrimination in the transfer from plasma to milk; the concentration in a bottle-fed baby increased substantially and rapidly from the level at or shortly after birth. Data for three babies were sufficiently extensive to permit determination of the biological half-life in each. Values of 8.7±0.6 days, 15.4±1.1 days, and 14.9±3.6 days were derived. (author)

  4. Half-life distribution table of radioactive nuclei

    International Nuclear Information System (INIS)

    Gugenberger, P.

    1954-01-01

    This table allows to identify an element if its period is known. Data for this table were taken from the half-life values adopted by Hollander, PERLMAN and SEABORG (Rev. mod. Phys., 1953, 22 number 2). Moreover for each nucleus, the mass number, the charge number and the type of decay are given in the table. (author) [fr

  5. Determination of disintegration half-life of 252Cf

    International Nuclear Information System (INIS)

    Chen Keliang; Liu Guoxing; Wang Sufang; Zheng Jiwen

    1991-01-01

    The follow-up measurements have been made by using a Si(Au) detector with small solid angle geometry for α disintegration of 252 Cf. The measured half-life of disintegration is 2.638 ± 0.009 year. This value is in accordance with other previous results

  6. Experimental half-life determination of 176Lu

    International Nuclear Information System (INIS)

    Kossert, Karsten; Jörg, Gerhard; Gostomski, Christoph Lierse v.

    2013-01-01

    The half-life of the naturally occurring long-lived rare earth isotope 176 Lu was determined by a combination of highly sophisticated experimental procedures in order to further improve the reliability and the precision of literature data. The amount of lutetium in the samples was determined by inductively coupled plasma optical emission spectrometry (ICP-OES) using a NIST reference standard. The isotopic ratio N( 176 Lu)/N(Lu) in the samples was measured by means of inductively coupled plasma high resolution mass spectrometry (ICP-HRMS). The activity divided by the mass of Lu was determined by applying liquid scintillation (LS) counting. The LS counting efficiency of the beta/gamma emitter 176 Lu was determined with the CIEMAT/NIST efficiency tracing technique with low uncertainty. The influences of colour quenching and background effects are discussed in this paper. The half-life was found to be 3.640(35)×10 10 y. The result is in good agreement with other evaluations and the relative standard uncertainty of 0.95% is among the lowest of previously published data. - Highlights: • The half-life of 176 Lu was determined by ICP-OES, ICP-HRMS and LSC. • The LSC efficiency was determined with the CIEMAT/NIST method. • The half-life was found to be 3.640(35)×10 10 y

  7. Beyond effective half-life characterization of radionuclide dynamics

    International Nuclear Information System (INIS)

    Hermanska, J.; Blazek, T.; Karny, M.

    1996-01-01

    A refined model was set up and tested of the effective radionuclide half-life in nuclear medicine, making allowance for the fact that the basic assumption that the observed data can be fitted by a mono-exponential, as well as some other assumptions, is not true. The results are discussed. (P.A.). 1 tab., 32 refs

  8. Half-life of the superallowed β+ emitter Ne18

    Science.gov (United States)

    Grinyer, G. F.; Smith, M. B.; Andreoiu, C.; Andreyev, A. N.; Ball, G. C.; Bricault, P.; Chakrawarthy, R. S.; Daoud, J. J.; Finlay, P.; Garrett, P. E.; Hackman, G.; Hyland, B.; Leslie, J. R.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Schumaker, M. A.; Svensson, C. E.; Valiente-Dobón, J. J.; Williams, S. J.; Zganjar, E. F.

    2007-08-01

    The half-life of Ne18 has been determined by detecting 1042-keV γ rays in the daughter F18 following the superallowed-Fermi β+ decay of samples implanted at the center of the 8πγ-ray spectrometer, a spherical array of 20 HPGe detectors. Radioactive Ne18 beams were produced on-line, mass-separated, and ionized using an electron-cyclotron-resonance ionization source at the ISAC facility at TRIUMF in Vancouver, Canada. This is the first high-precision half-life measurement of a superallowed Fermi β decay to utilize both a large-scale HPGe spectrometer and the isotope separation on-line technique. The half-life of Ne18, 1.6656 ± 0.0019 s, deduced following a 1.4σ correction for detector pulse pile-up, is four times more precise than the previous world average. As part of an investigation into potential systematic effects, the half-life of the heavier isotope Ne23 was determined to be 37.11 ± 0.06 s, a factor of 2 improvement over the previous precision.

  9. Measurement of the 8Li half-life

    International Nuclear Information System (INIS)

    Flechard, X.; Lienard, E.; Naviliat-Cuncic, O.; Ban, G.; Carniol, B.; Etasse, D.; Fontbonne, J. M.; Rodriguez, D.; Lallena, A. M.; Alvarez, M. A. G.; Praena, J.

    2010-01-01

    We report a new measurement of the 8 Li half-life using a plastic scintillator and an ultrafast waveform digitizing module. The result, T 1/2 =(838.40±0.36) ms, improves by a factor of 2.5 the most precise result obtained so far and is furthermore deduced with negligible corrections due to dead time.

  10. Radioactive source simulation for half-life experiment

    International Nuclear Information System (INIS)

    Wanitsuksombut, Warapon; Decthyothin, Chanti

    1999-01-01

    A simulation of radioactivity decay by using programmable light source with a few minutes half-life is suggested. A photodiode with digital meter label in cps is use instead of radiation detector. Both light source and photodiode are installed in a black box to avoid surrounding room light. The simulation set can also demonstrate Inverse Square Law experiment of radiation penetration. (author)

  11. Measurement of the 230U half-life

    International Nuclear Information System (INIS)

    Pommé, S.; Altzitzoglou, T.; Van Ammel, R.; Suliman, G.; Marouli, M.; Jobbágy, V.; Paepen, J.; Stroh, H.; Apostolidis, C.; Abbas, K.; Morgenstern, A.

    2012-01-01

    The 230 U half-life was determined by measuring the decay curve of 230 U sources by various nuclear detection techniques: α-particle counting at a defined small solid angle; 4πα+β counting with a windowless CsI sandwich spectrometer, a liquid scintillation counter and a pressurised proportional counter; gamma-ray spectrometry with a HPGe detector and nearly-2π α-particle counting with an ion-implanted silicon detector. Depending on the technique, the decay was followed for 100–200 d, which is 5–10 times the 230 U half-life. The measurement results of the various techniques were in good mutual agreement. The mean value, T 1/2 ( 230 U)=20.23 (2) d, is lower than the literature value which is based on one measurement in 1948 and resulted in a half-life value of 20.8 d without statement of uncertainty. A correction for the ingrowth of the long-lived 210 Pb and its daughter products may have been overlooked in the past. - Highlights: ► Half-life of 230 U determined by various nuclear detection techniques. ► Result T 1/2 ( 230 U)=20.23 (2) d is lower than the literature value. ► 230 U/ 226 Th decay series has potential use in alpha-immunotherapy.

  12. Measurement of the half-life of 68Ga

    International Nuclear Information System (INIS)

    García-Toraño, Eduardo; Peyrés Medina, Virginia; Romero, Eduardo; Roteta, Miguel

    2014-01-01

    The half-life of the positron-emitter 68 Ga has been measured by following the decay rate with two systems based on ionization chamber and Ge detectors. The decay rate was measured for periods of time up to 10 half-lives. The combination of the 6 results obtained with both systems gives a value of T 1/2 =67.845(18) min, in good agreement with recommended data and with an uncertainty lower than any other previously reported value. - Highlights: • The half-life of the positron-emitter radionuclide 68 Ga was measured. • Two measurement setups (ionization chamber and Ge detector) were used. • Results agree with evaluated data but exhibit lower uncertainty

  13. Superior serum half life of albumin tagged TNF ligands

    International Nuclear Information System (INIS)

    Mueller, Nicole; Schneider, Britta; Pfizenmaier, Klaus; Wajant, Harald

    2010-01-01

    Due to their immune stimulating and apoptosis inducing properties, ligands of the TNF family attract increasing interest as therapeutic proteins. A general limitation of in vivo applications of recombinant soluble TNF ligands is their notoriously rapid clearance from circulation. To improve the serum half life of the TNF family members TNF, TWEAK and TRAIL, we genetically fused soluble variants of these molecules to human serum albumin (HSA). The serum albumin-TNF ligand fusion proteins were found to be of similar bioactivity as the corresponding HSA-less counterparts. Upon intravenous injection (i.v.), serum half life of HSA-TNF ligand fusion proteins, as determined by ELISA, was around 15 h as compared to approximately 1 h for all of the recombinant control TNF ligands without HSA domain. Moreover, serum samples collected 6 or 24 h after i.v. injection still contained high TNF ligand bioactivity, demonstrating that there is only limited degradation/inactivation of circulating HSA-TNF ligand fusion proteins in vivo. In a xenotransplantation model, significantly less of the HSA-TRAIL fusion protein compared to the respective control TRAIL protein was required to achieve inhibition of tumor growth indicating that the increased half life of HSA-TNF ligand fusion proteins translates into better therapeutic action in vivo. In conclusion, our data suggest that genetic fusion to serum albumin is a powerful and generally applicable mean to improve bioavailability and in vivo activity of TNF ligands.

  14. Half-life predictions for decay modes of superheavy nuclei

    International Nuclear Information System (INIS)

    Duarte, S.B.; Tavares, O.A.P.; Goncalves, M.; Rodriguez, O.; Guzman, F.; Barbosa, T.N.; Garcia, F.; Dimarco, A.

    2004-09-01

    We applied the Effective Liquid Drop Model (ELDM) to predict the alpha-decay, cluster emission and cold fission half-life-values of nuclei in the region of Superheavy Elements (SHE). The present calculations have been made in the region of the ZN-plane defined by 155 <=N <=220 and 110<=Z<=135. Shell effects are included via the Q-value of the corresponding decay case. We report the results of a systematic calculation of the half-life for the three nuclear decay modes in a region of the ZN-plane where superheavy elements are expected to be found. Results have shown that, among the decay modes investigated here, the alpha decay is the dominant one. i.e, the decay mode of smallest half-lives. Half-life predictions for alpha decay, cluster emission and cold fission for the isotopic family of the most recent SHE detected of Z=115 and for the isotopic family of the already consolidated SHE of Z=111 are presented. (author)

  15. Beryllium-10: Half-life and AMS-standards

    International Nuclear Information System (INIS)

    Hofmann, H.J.; Beer, J.; Bonani, G.; von Gunten, H.R.; Raman, S.; Suter, M.; Walker, R.L.; Woelfli, W.; Zimmermann, D.

    1987-01-01

    Absolute AMS measurements of 10 Be require reliable standards for calibration. Among the existing standards, rather large differences have been observed. These differences were found partially to be due to the different half-life values which were assumed. Also for comparison of AMS data with activity measurements, it is necessary to know the 10 Be half-life as precisely as possible. Starting with 5 ml of the standardized ORNL-MASTER solution, a working solution with a well-defined 10 Be content was prepared. Its specific activity was determined by liquid scintillation counting. This measurement yielded a new value of (1.52 +- 0.05) My for the 10 Be half-life, which is in agreement with the previously reported values but is about three times more accurate. Two independent dilution series produced new AMS standards with 10 Be/ 9 Be ratios of the order of 10 -10 and 10 -11 . These standards were measured at the ETH/SIN AMS facility with high accuracy and are compared with other available 10 Be standards. 15 refs, 2 figs., 3 tabs

  16. Extremely Short Optical Pulses and Ads/CFT Compliance

    Directory of Open Access Journals (Sweden)

    Konobeeva N.N.

    2015-01-01

    Full Text Available Dynamics of few cycle optical pulses in non-Fermi liquid was considered. Energy spectrum of non-Fermi liquid was taken from the AdS/CFT compliance. Conditions of quasiparticle excitation existence were defined. Non-Fermi liquid parameters impact on the shape of few cycle pulses were estimated. It was shown that extremely short optical pulse propagation in the non-Fermi liquid is a stable pattern. The value of chemical potential has a significant impact on extremely short pulse shape. An increase in initial pulse amplitude does not result in pulse-shape distortions under its propagation in considered medium that is why the non-Fermi liquid can be used in applications inherent in extremely short pulse processing.

  17. Precision half-life measurement of 17F

    Science.gov (United States)

    Brodeur, M.; Nicoloff, C.; Ahn, T.; Allen, J.; Bardayan, D. W.; Becchetti, F. D.; Gupta, Y. K.; Hall, M. R.; Hall, O.; Hu, J.; Kelly, J. M.; Kolata, J. J.; Long, J.; O'Malley, P.; Schultz, B. E.

    2016-02-01

    Background: The precise determination of f t values for superallowed mixed transitions between mirror nuclide are gaining attention as they could provide an avenue to test the theoretical corrections used to extract the Vu d matrix element from superallowed pure Fermi transitions. The 17F decay is particularly interesting as it proceeds completely to the ground state of 17O, removing the need for branching ratio measurements. The dominant uncertainty on the f t value of the 17F mirror transition stems from a number of conflicting half-life measurements. Purpose: A precision half-life measurement of 17F was performed and compared to previous results. Methods: The life-time was determined from the β counting of implanted 17F on a Ta foil that was removed from the beam for counting. The 17F beam was produced by transfers reaction and separated by the TwinSol facility of the Nuclear Science Laboratory of the University of Notre Dame. Results: The measured value of t1/2 new=64.402 (42) s is in agreement with several past measurements and represents one of the most precise measurements to date. In anticipation of future measurements of the correlation parameters for the decay and using the new world average t1/2 world=64.398 (61) s, we present a new estimate of the mixing ratio ρ for the mixed transition as well as the correlation parameters based on assuming Standard Model validity. Conclusions: The relative uncertainty on the new world average for the half-life is dominated by the large χ2=31 of the existing measurements. More precision measurements with different systematics are needed to remedy to the situation.

  18. Dependence of radiocaesium biological half-life in freshwater fish on water potassium concentration and temperature

    International Nuclear Information System (INIS)

    Carreiro, M.C.V.; Corisco, J.A.G.

    1998-01-01

    Short-term experiments (35-49 days) showed that the rate of cesium elimination from fish increases with increasing potassium concentration in water (the biological half-life decreases); this, however, is only true of the potassium concentration range of 0.35 to 3.5 ppm, whereas higher potassium concentrations do not seem to affect the elimination rate. Decrease in water temperature within the 20 degC to 5 degC range slows down the cesium elimination process. (P.A.)

  19. Fenobody: A Ferritin-Displayed Nanobody with High Apparent Affinity and Half-Life Extension.

    Science.gov (United States)

    Fan, Kelong; Jiang, Bing; Guan, Zhe; He, Jiuyang; Yang, Dongling; Xie, Ni; Nie, Guohui; Xie, Can; Yan, Xiyun

    2018-04-10

    Nanobodies consist of a single domain variable fragment of a camelid heavy-chain antibody. Nanobodies have potential applications in biomedical fields because of their simple production procedures and low cost. Occasionally, nanobody clones of interest exhibit low affinities for their target antigens, which, together with their short half-life limit bioanalytical or therapeutic applications. Here, we developed a novel platform we named fenobody, in which a nanobody developed against H5N1 virus is displayed on the surface of ferritin in the form of a 24mer. We constructed a fenobody by substituting the fifth helix of ferritin with the nanobody. TEM analysis showed that nanobodies were displayed on the surface of ferritin in the form of 6 × 4 bundles, and that these clustered nanobodies are flexible for antigen binding in spatial structure. Comparing fenobodies with conventional nanobodies currently used revealed that the antigen binding apparent affinity of anti-H5N1 fenobody was dramatically increased (∼360-fold). Crucially, their half-life extension in a murine model was 10-fold longer than anti-H5N1 nanobody. In addition, we found that our fenobodies are highly expressed in Escherichia coli, and are both soluble and thermo-stable nanocages that self-assemble as 24-polymers. In conclusion, our results demonstrate that fenobodies have unique advantages over currently available systems for apparent affinity enhancement and half-life extension of nanobodies. Our fenobody system presents a suitable platform for various large-scale biotechnological processes and should greatly facilitate the application of nanobody technology in these areas.

  20. Thyroid fractional deposition and half life of radioiodine

    International Nuclear Information System (INIS)

    Fujita, Minoru

    1974-01-01

    In order to measure the absorbed dose of radioiodine in the thyroid gland, which was incorporated by halation or ingestion, iodine intake (fa), 131 I thyroid uptake rate(fw), 131 I thyroid uptake rate compared to the rate in the whole body (f 2 ) and the half life of iodine in the thyroid gland(Teff) were examined. Thyroid fractional deposition of 131 I was compared between Japanese and European. The rate of 131 I which moved from the blood into the thyroid gland in children (f 2 ') and the effect of the iodine in meals on 131 I thyroid uptake (fw) were also studied. In Japanese, f 2 was 0.28 and the mean Teff was 6.9 +- 0.7 days in 11 Japanese adults. There was an individual difference in these biological parameter and the values in adults were different from those in children. A little difference in value between Japanese and European suggested to be caused by the greater amount of stable iodine in meals in Japanese. (Serizawa, K.)

  1. A formula for half-life of proton radioactivity

    Science.gov (United States)

    Zhang, Zhi-Xing; Dong, Jian-Min

    2018-01-01

    We present a formula for proton radioactivity half-lives of spherical proton emitters with the inclusion of the spectroscopic factor. The coefficients in the formula are calibrated with the available experimental data. As an input to calculate the half-life, the spectroscopic factor that characterizes the important information on nuclear structure should be obtained with a nuclear many-body approach. This formula is found to work quite well, and in better agreement with experimental measurements than other theoretical models. Therefore, it can be used as a powerful tool in the investigation of proton emission, in particular for experimentalists. Supported by National Natural Science Foundation of China (11435014, 11405223, 11675265, 11575112), the 973 Program of China (2013CB834401, 2013CB834405), National Key Program for S&T Research and Development (2016YFA0400501), the Knowledge Innovation Project (KJCX2-EW-N01) of Chinese Academy of Sciences, the Funds for Creative Research Groups of China (11321064) and the Youth Innovation Promotion Association of Chinese Academy of Sciences

  2. On the way to high-power linear proton accelerator for the long half-life radionuclides transmutation

    International Nuclear Information System (INIS)

    Batskikh, G.I.; Lupandin, O.S.; Murin, B.P.; Fedotov, A.P.

    1991-01-01

    The concept of continuous mode high-power linear proton accelerator with 1.5 GeV energy, 0.3 A current for the long half-life nuclides transmutation into the short ones (waste of atomic power plants (APP)) is proposed. The accelerator design main principles, scheme and parameters are presented. The accent is made on the accelerator efficiency, reliability and radiation purity. (author)

  3. Accurate γ-ray spectrometry measurements of the half-life of 92Sr

    International Nuclear Information System (INIS)

    Leconte, P.; Hudelot, J.P.; Antony, M.

    2008-01-01

    Studies of the nuclear fuel cycle require an accurate knowledge of the energy release from the decay of radioactive nuclides produced in a reactor, including precise half-life data for the short-lived radionuclides. Moreover, short-lived fission products are crucial for fission rate distribution measurements performed in low-power facilities, such as EOLE and MINERVE of CEA Cadarache [Fougeras, P., 2005. EOLE, MINERVE and MASURCA facilities and their associated neutron experimental programs. In: 13th International Conference on Nuclear Engineering, Beijing, China, 16-20 May 2005], and their nuclear decay data need to be known to high precision. For these reasons, the half-life of 92 Sr has been measured to solve a recently observed inconsistency identified with the quoted value in the main nuclear applications libraries (including JEFF3.1): T 1/2 =2.71±0.01 h [Parsa, B., Ashari, A., Goolvard, L., Nobar, Y.M., 1971. Decay scheme of 2.71 h 92 Sr. Nucl. Phys. A 175, 629-640]. An overestimation of 4.5% has been identified in this work, based on two independent methods. Specific γ-ray spectrometry measurements on activated fissile foils have been carried out, using two HPGe detectors. Influencing factors such as net area measurements of photopeaks, pulse pile-up accuracy and dead time corrections in the presence of decaying activity are discussed. A new value has been obtained by combining eight series of measurements: T 1/2 =2.594±0.006 h. The uncertainty has been reduced by a factor of two with respect to previous evaluations. This measured value also shows good agreement with the most recent studies of T 1/2 =2.627±0.009 h [Nir-El, Y., 2003. Private Communications. Soreq Research Centre, Yavne, Israel

  4. Precise half-life measurement of the superallowed emitter 30S

    Science.gov (United States)

    Iacob, V. E.; Hardy, J. C.; Chen, L.; Horvat, V.; Bencomo, M.; Nica, N.; Park, H. I.; Roeder, B. T.; Saastamoinen, A.

    2018-03-01

    We have measured the half-life of 30S, the parent of a superallowed 0+→0+β transition, to a high precision using very pure sources and a 4 π proportional gas counter to detect the decay positrons. Our result for the half-life is 1.179 92(34) s. As a by-product of this measurement, we determine the half-life of its daughter, 30P, to be 2.501(2) min.

  5. On the 209Po half-life error and its confirmation. A critique

    International Nuclear Information System (INIS)

    Colle, R.; Colle, A.M.

    2016-01-01

    A recent report on 209 Po claimed to have made a determination of the 125-a half-life from measurements made over 0.8 % of one half-life. A careful reanalysis of the original data with a more complete and rigorous consideration of the underlying uncertainties demonstrates that this claim cannot withstand critical scrutiny. More importantly, this critique examines the larger issue as to what constitutes a valid half-life determination, and highlights that a careful and realistic analysis beyond the mere fitting of decay data to an exponential function is required for the measurement and reporting of half-life values. (author)

  6. The ecological half-life of 137Cs in undisturbed silt soil

    International Nuclear Information System (INIS)

    Drosg, M.

    2012-01-01

    The time necessary to safely cultivate agricultural areas after they have been contaminated by radioactivity (e.g. after the Chernobyl accident) is not determined by the physical half-life of the radioactive isotopes in question but by their (usually much shorter) ecological half-life (). This half-life not only depends on the type of soil but also on whether the soil was fertilized or not. Therefore it is not possible to determine an ecological half-life that is universally valid. However, the value for undisturbed, unfertilized soil should provide a general indication for the duration of ecological half-life. In a silt soil in Vienna, Austria, the ecological half-life of 137 Cs was determined to be 0.8 years, which is much shorter than the physical half-life of 30 years. - Highlights: ► Absolute measurements of 137 Cs radioactivity in leaves of perennial plants. ► The natural 40 K radioactivity served as reference. ► The ecological half-life of 137 Cs in loamy soil was determined.

  7. The half-life of 227Th by direct and indirect measurements

    International Nuclear Information System (INIS)

    Collins, S.M.; Pommé, S.; Jerome, S.M.; Ferreira, K.M.; Regan, P.H.; Pearce, A.K.

    2015-01-01

    Utilising a chemically purified solution the radioactive half-life of 227 Th has been determined indirectly by observation of the ingrowth of 223 Ra using an ionisation chamber (IC) and for the first time by direct observation of the change in activity with time using a high-purity germanium (HPGe) γ-ray spectrometer. The radioactive decay was observed for ~104 days (~5.6 half-lives) by γ-ray spectrometry and approximately 63 days and 72 days (~3.4 and ~3.9 half-lives) using an ionisation chamber (IC). The resulting half-life values – 18.695 (4) days (IC) and 18.683 (20) days (HPGe) – are consistent and detailed uncertainty budgets are presented for the two measurement techniques. A weighted mean of our results of 18.695 (4) days is inconsistent with the most precise published half-life value of 18.7176 (52) days (Jordan and Blanke, 1967). A critical evaluation of literature data has been performed, indicating a paucity of reliable and independent measurements. Selected independent published values have been used to determine a recommended half-life of 18.697 (7) days. A method has been introduced in the course of this work so that the recommended half-life of 227 Th as determined by ingrowth can be modified if a different 223 Ra half-life has been determined, evaluated and adopted. - Highlights: • First direct measurement of 227 Th half-life by HPGe γ-ray spectrometry. • Precision half-life measurement by ionisation chamber. • New half-life of 18.695 (4) days determined. • Critical evaluation of published half-lives and recommended value determined

  8. Half-life evaluations for 3H, 90Sr, and 90Y

    International Nuclear Information System (INIS)

    MacMahon, Desmond

    2006-01-01

    A recent paper has reviewed methods for the evaluation of discrepant sets of data and demonstrated the results of applying these methods to the published half-life data of 90 Sr and 137 Cs [MacMahon, T.D., Pearce, A., Harris, P., 2004. Convergence of techniques for the evaluation of discrepant data. Appl. Radiat. Isot. 60, 275-281]. The half-life data for 3 H has been subject to a comprehensive review and critical evaluation by Lucas and Unterweger [2000. Comprehensive review and critical evaluation of the half-life of tritium. J. Res. Natl. Inst. Stand. Technol. 105, 541-549]. The current paper reports the results of applying the various evaluation procedures of MacMahon et al. Convergence of techniques for the evaluation of discrepant data. Appl. Radiat. Isot. 60, 275-281] to the data of Lucas and Unterweger [Comprehensive review and critical evaluation of the half-life of tritium. J. Res. Natl. Inst. Stand. Technol. 105, 541-549], resulting in a recommended half-life of 4497(4) days. MacMahon et al. [Convergence of techniques for the evaluation of discrepant data. Appl. Radiat. Isot. 60, 275-281] highlighted problems in the evaluation of the discrepant half-life data of 90 Sr, in particular the worrying upward trend in the data, where the weighted mean of all the measurements increases, on average, by 35 days each time a new measurement result is added. The current paper reports on further analyses of these data. New measurements of the half-life of 90 Y have been reported by Kossert and Schrader [2004. Standardization by liquid scintillation counting and half-life measurements of 90 Y. Appl. Radiat. Isot. 60, 741]. This has prompted a new evaluation of all available published 90 Y half-life data. The data are fairly consistent, and a value of 64.063(16) h is recommended

  9. Update of NIST half-life results corrected for ionization chamber source-holder instability.

    Science.gov (United States)

    Unterweger, M P; Fitzgerald, R

    2014-05-01

    As reported at the ICRM 2011, it was discovered that the source holder used for calibrations in the NIST 4πγ ionization chamber (IC) was not stable. This has affected a large number of half-life measurement results previously reported and used in compilations of nuclear data. Corrections have been made on all of the half-life data based on the assumption that the changes to the ionization chamber response were gradual. The corrections are energy dependent and therefore radionuclide specific. This presentation will review our results and present the recommended changes in half-life values and/or uncertainties. © 2013 Published by Elsevier Ltd.

  10. Update of NIST half-life results corrected for ionization chamber source-holder instability

    International Nuclear Information System (INIS)

    Unterweger, M.P.; Fitzgerald, R.

    2014-01-01

    As reported at the ICRM 2011, it was discovered that the source holder used for calibrations in the NIST 4πγ ionization chamber (IC) was not stable. This has affected a large number of half-life measurement results previously reported and used in compilations of nuclear data. Corrections have been made on all of the half-life data based on the assumption that the changes to the ionization chamber response were gradual. The corrections are energy dependent and therefore radionuclide specific. This presentation will review our results and present the recommended changes in half-life values and/or uncertainties. - Highlights: • The NIST half-life data is corrected for sample positioning variations and refitted. • These results are reported and increased errors in the reported values are given. • Longer lived radionuclides are discussed

  11. Influence of sex and age on the biological half-life of cadmium in mice

    International Nuclear Information System (INIS)

    Taguchi, T.; Suzuki, S.

    1981-01-01

    The influence of age on the whole-body biological half-life of 109 Cd was studied in male mice following ip injection. The influence of sex on whole-body and organ retention was ascertained after sc injection. The whole-body biological half-life of 109 Cd of the older mice was more than twice that of the younger mice, and that of the female mice was longer than that of the males. These differences demonstrate a biological difference between males and females with respect to whole-body half-life of 109 Cd. The effects of age and sex on the biological half-life of Cd in mice are assessed quantitatively

  12. The HP 9825 A program for the determination of an isotope half-life

    International Nuclear Information System (INIS)

    Jujuratisbela, Uju.

    1980-01-01

    Determination of half life of gold 198, indium 116, manganese 56, copper 64 are presented, using least squares method in HP 9825 A. This method is more accurate and needs less time than graphic method. (author tr.)

  13. Designing of peptides with desired half-life in intestine-like environment

    KAUST Repository

    Sharma, Arun; Singla, Deepak; Rashid, Mamoon; Raghava, Gajendra Pal Singh

    2014-01-01

    hindered mainly because of their high susceptibility towards proteases degradation. We have developed an in silico method to predict the half-life of peptides in intestine-like environment and to design better peptides having optimized physicochemical

  14. Standardization of 40 K by liquid scintillation counting. Determination of the half-life

    International Nuclear Information System (INIS)

    Grau Carles, A.; Grau Malonda, A.

    1997-01-01

    The relative abundance of the natural radioisotope ''40 K in environmental samples frequently generates interferences in low activity measurements. In the present study we propose the determination of ''40 K by the CIEMAT/NIST method. On this context, the verification of ''40 K half-life is required. We present a half-life value obtained by liquid scintillation counting in excellent agreement with those reported in the literature. (Author)

  15. Goiania radiation accident: 30 years - a half-life for a whole life..

    International Nuclear Information System (INIS)

    Reis, R.G.; Lucena, E.A.; Arantes, R.R.; Silva, A.A.; Reis, A.A.

    2017-01-01

    The radiological accident in Goiânia, Brazil, considered the largest urban radiological accident in the world, generated several publications in the technical area that are widely disseminated in the scientific literature, given the importance of the lessons learned. However, in a simple conversation with people who worked on that accident, it is noted that many reports have not been recorded. In this year in which 30 years of the event is completed, it will be of great value to record personal testimonies that are not in technical or scientific books. And what can we tell after a half-life that lasted for a lifetime? The lived stories, the situations, the improvisations, the way to solve, the overcoming, the human side, the emotions, happy or sad, short or long, funny or not. The objective of this work is to preserve, maintain and divulge reports and situations experienced by people who worked on the radiological accident with Cs-137 in Goiânia. Audio or video recordings about experiences lived in Goiânia by people who worked in that emergency situation were carried out. The reports are free and the form of registration is always at the discretion of the narrator. Storing records allows to preserve, maintain, and disclose the accident to other generations

  16. Using gamma distribution to determine half-life of rotenone, applied in freshwater

    Energy Technology Data Exchange (ETDEWEB)

    Rohan, Maheswaran, E-mail: mrohan@aut.ac.nz [Department of Biostatistics and Epidemiology, Auckland University of Technology, Auckland (New Zealand); Fairweather, Alastair; Grainger, Natasha [Science and Capability, Department of Conservation, Hamilton (New Zealand)

    2015-09-15

    Following the use of rotenone to eradicate invasive pest fish, a dynamic first-order kinetic model is usually used to determine the half-life and rate at which rotenone dissipated from the treated waterbody. In this study, we investigate the use of a stochastic gamma model for determining the half-life and rate at which rotenone dissipates from waterbodies. The first-order kinetic and gamma models produced similar values for the half-life (4.45 days and 5.33 days respectively) and days to complete dissipation (51.2 days and 52.48 days respectively). However, the gamma model fitted the data better and was more flexible than the first-order kinetic model, allowing us to use covariates and to predict a possible range for the half-life of rotenone. These benefits are particularly important when examining the influence that different environmental factors have on rotenone dissipation and when trying to predict the rate at which rotenone will dissipate during future operations. We therefore recommend that in future the gamma distribution model is used when calculating the half-life of rotenone in preference to the dynamic first-order kinetics model. - Highlights: • We investigated the use of the gamma model to calculate the half-life of rotenone. • Physical and environmental variables can be incorporated into the model. • A method for calculating the range around a mean half-life is presented. • The model is more flexible than the traditionally used first-order kinetic model.

  17. Variation in absorption and half-life of hydrocortisone influence plasma cortisol concentrations.

    Science.gov (United States)

    Hindmarsh, Peter C; Charmandari, Evangelia

    2015-04-01

    Hydrocortisone therapy should be individualized in congenital adrenal hyperplasia (CAH) patients to avoid over and under replacement. We have assessed how differences in absorption and half-life of cortisol influence glucocorticoid exposure. Forty-eight patients (21 M) aged between 6·1 and 20·3 years with CAH due to CYP21A2 deficiency were studied. Each patient underwent a 24-h plasma cortisol profile with the morning dose used to calculate absorption parameters along with an intravenous (IV) hydrocortisone (15 mg/m(2) body surface area) bolus assessment of half-life. Parameters derived were maximum plasma concentration (Cmax ), time of maximum plasma concentration (tmax ), time to attaining plasma cortisol concentration cortisol. Mean half-life was 76·5 ± 5·2 (range 40-225·3) min, Cmax 780·7 ± 61·6 nmol/l and tmax 66·7 (range 20-118) min. Time taken to a plasma cortisol concentration less than 100 nmol/l was 289 (range 140-540) min. Those with a fast half-life and slow tmax took longest to reach a plasma cortisol concentration less than 100 nmol/l (380 ± 34·6 min), compared to those with a slow half-life and fast tmax (298 ± 34·8 min) and those with a fast half-life and fast tmax (249·5 ± 14·4 min) (One-way anovaF = 4·52; P = 0·009). Both rate of absorption and half-life of cortisol in the circulation play important roles in determining overall exposure to oral glucocorticoid. Dose regimens need to incorporate estimates of these parameters into determining the optimum dosing schedule for individuals. © 2014 John Wiley & Sons Ltd.

  18. Designing of peptides with desired half-life in intestine-like environment

    KAUST Repository

    Sharma, Arun

    2014-08-20

    Background: In past, a number of peptides have been reported to possess highly diverse properties ranging from cell penetrating, tumor homing, anticancer, anti-hypertensive, antiviral to antimicrobials. Owing to their excellent specificity, low-toxicity, rich chemical diversity and availability from natural sources, FDA has successfully approved a number of peptide-based drugs and several are in various stages of drug development. Though peptides are proven good drug candidates, their usage is still hindered mainly because of their high susceptibility towards proteases degradation. We have developed an in silico method to predict the half-life of peptides in intestine-like environment and to design better peptides having optimized physicochemical properties and half-life.Results: In this study, we have used 10mer (HL10) and 16mer (HL16) peptides dataset to develop prediction models for peptide half-life in intestine-like environment. First, SVM based models were developed on HL10 dataset which achieved maximum correlation R/R2 of 0.57/0.32, 0.68/0.46, and 0.69/0.47 using amino acid, dipeptide and tripeptide composition, respectively. Secondly, models developed on HL16 dataset showed maximum R/R2 of 0.91/0.82, 0.90/0.39, and 0.90/0.31 using amino acid, dipeptide and tripeptide composition, respectively. Furthermore, models that were developed on selected features, achieved a correlation (R) of 0.70 and 0.98 on HL10 and HL16 dataset, respectively. Preliminary analysis suggests the role of charged residue and amino acid size in peptide half-life/stability. Based on above models, we have developed a web server named HLP (Half Life Prediction), for predicting and designing peptides with desired half-life. The web server provides three facilities; i) half-life prediction, ii) physicochemical properties calculation and iii) designing mutant peptides.Conclusion: In summary, this study describes a web server \\'HLP\\' that has been developed for assisting scientific

  19. 18F half-life measurement using a high-purity germanium detector

    International Nuclear Information System (INIS)

    Han, Jubong; Lee, K.B.; Park, T.S.; Lee, J.M.; Oh, P.J.; Lee, S.H.; Kang, Y.S.; Ahn, J.K.

    2012-01-01

    The half-life of 18 F has been measured using HPGe detectors with a 137 Cs reference source. The counting ratio of 511 keV γ-rays from 18 F to 622 keV γ-rays from 137 Cs was fitted for the half-life with a weighted least-square method. Uncertainties due to the systematic effects arising from the measurement of a high activity 18 F source were studied in detail. The half-life of 18 F was found to be (109.72±0.19) min. The result is in a good agreement with the recommended value of (109.728±0.019) min evaluated at the Laborotaire National Henri Becquerel (LNHB). - Highlights: ► The 18 F half-life was measured with a reference source and without it using HPGe detectors. ► We found the systematic effect ‘activity dynamic range effect’ by monitoring the counts of the reference source. ► This activity dynamic range effect was corrected by using the reference source method. ► The 18 F half-life using the reference source method was in a good agreement with the recommended value of LNHB.

  20. The half-life of 207Bi and decays of 211At and 211Po

    International Nuclear Information System (INIS)

    Yanokura, M.; Kudo, H.; Nakahara, H.; Miyano, K.; Ohya, S.; Nitoh, O.

    1978-01-01

    The half-life of 207 Bi was obtained from the genetic relation between 207 Po and 207 Bi, and between 211 At and 207 Bi. The half-life was found to be 33.4 +- 0.8 y. The half-life of 207 Po was determined to be 5.81 +- 0.04 h by following the decay of the characteristic γ-rays from 207 Po. The half-life of 211 At was determined to be 7.23 +- 0.02 h by following the decay of γ-rays and α-particles from 211 At and 211 Po. The half-lives determined in the present work for 207 Po and 211 At agree with the literature although the half-life of 207 Bi differs considerably from the currently accepted value of 38 y. The branching ratio of 211 At decaying through EC and α-decay modes was determined together with the branching ratios of the three α-particles emitted from 211 Po. (Auth.)

  1. Re-measurement of the half-life of sup 7 sup 9 Se

    CERN Document Server

    Jiang Song Sheng; Diao Li Jun; Li Chun Shen; GouJingRu; Wu Shao Yon

    2002-01-01

    A new attempt has been made for the re-measurement of the half-life of sup 7 sup 9 Se. We made two major improvements over our earlier sup 7 sup 9 Se half-life determination (Nucl. Instr. and Meth. B 123 (1997) 403). Firstly, the half-life of sup 7 sup 9 Se was measured relative to the precisely known half-life of sup 7 sup 5 Se, rather than an absolute measurement of sup 7 sup 9 Se/Se. Secondly, the Projectile X-ray Detection technique was used for the separation of sup 7 sup 9 Se from its isobar, sup 7 sup 9 Br, rather than measuring sup 8 sup 1 Br for the deduction of sup 7 sup 9 Br interference, and this technique was also used for separation of sup 7 sup 5 Se and its isobar, sup 7 sup 5 As. A detailed description of the sample preparations, experimental setup and measurements are given. The re-measured half-life of sup 7 sup 9 Se was (2.95+-0.38)x10 sup 5 a, about a factor of 3 lower than the previous value, 1.1x10 sup 6 a. The problems in the previous measurement are discussed.

  2. High-precision half-life determination for the superallowed β+ emitter Ga62

    Science.gov (United States)

    Grinyer, G. F.; Finlay, P.; Svensson, C. E.; Ball, G. C.; Leslie, J. R.; Austin, R. A. E.; Bandyopadhyay, D.; Chaffey, A.; Chakrawarthy, R. S.; Garrett, P. E.; Hackman, G.; Hyland, B.; Kanungo, R.; Leach, K. G.; Mattoon, C. M.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Ressler, J. J.; Sarazin, F.; Savajols, H.; Schumaker, M. A.; Wong, J.

    2008-01-01

    The half-life of the superallowed β+ emitter Ga62 has been measured at TRIUMF's Isotope Separator and Accelerator facility using a fast-tape-transport system and 4π continuous-flow gas proportional counter to detect the positrons from the decay of Ga62 to the daughter Zn62. The result, T1/2=116.100±0.025 ms, represents the most precise measurement to date (0.022%) for any superallowed β-decay half-life. When combined with six previous measurements of the Ga62 half-life, a new world average of T1/2=116.121±0.021 ms is obtained. This new half-life measurement results in a 20% improvement in the precision of the Ga62 superallowed ft value while reducing its mean by 0.9σ to ft=3074.3(12) s. The impact of this half-life measurement on precision tests of the CVC hypothesis and isospin symmetry breaking corrections for A⩾62 superallowed decays is discussed.

  3. Determination of plutonium-241 half-life by mass spectrometric measurement

    International Nuclear Information System (INIS)

    Hiyama, Takashi; Wada, Yukio; Onishi, Koichi

    1982-01-01

    Much data for Pu-241 half-life have been reported, but these values range from 13.8 years to 15.1 years depending on investigators. In order to define the half-life of Pu-241, the half-life was calculated by analyzing the mass spectrometry data obtained in the author's laboratory over the past six years on Plutonium Isotopic Standard Reference Materials prepared at the National Bureau of Standards (NBS). The sample used for this work consisted of SRM-947 and SRM-948 prepared at NBS. Before mass spectrometric analysis, the plutonium aliquot was separated from its Am-241 daughter by anion exchange chromatography, since Am-241 is not distinguished from Pu-241 in the mass spectrometer. 241 Pu/ 239 Pu and 241 Pu/ 240 Pu ratios were calculated from the values of mass spectrometric measurement. From the relation of log N to time, the half-life of Pu-241 was determined, based on the slope using a least squares fit. The half-life of Pu-241 was estimated to be 14.29+-0.15 years. (Yoshitake, I.)

  4. An albumin-oligonucleotide assembly for potential combinatorial drug delivery and half-life extension applications

    DEFF Research Database (Denmark)

    Kuhlmann, Matthias; Hamming, Jonas Bohn Refslund; Voldum, Anders

    2017-01-01

    The long blood circulatory property of human serum albumin, due to engagement with the cellular recycling neonatal Fc receptor (FcRn), is an attractive drug half-life extension enabling technology. This work describes a novel site-specific albumin double-stranded (ds) DNA assembly approach, in wh...... technology platform that offers potential combinatorial drug delivery and half-life extension applications.......The long blood circulatory property of human serum albumin, due to engagement with the cellular recycling neonatal Fc receptor (FcRn), is an attractive drug half-life extension enabling technology. This work describes a novel site-specific albumin double-stranded (ds) DNA assembly approach......, in which the 3' or 5' end maleimide-derivatized oligodeoxynucleotides are conjugated to albumin cysteine at position 34 (cys34) and annealed with complementary strands to allow single site-specific protein modification with functionalized ds oligodeoxynucleotides. Electrophoretic gel shift assays...

  5. The elimination half-life of benzodiazepines and fall risk: two prospective observational studies.

    Science.gov (United States)

    de Vries, Oscar J; Peeters, Geeske; Elders, Petra; Sonnenberg, Caroline; Muller, Majon; Deeg, Dorly J H; Lips, Paul

    2013-11-01

    the STOPP criteria advise against the use of long-acting benzodiazepines (LBs). to study whether LBs are associated with a higher fall risk than short-acting benzodiazepines (SBs) (elimination half-life ≤ 10 h). we used base-line data and prospective fall follow-up from the Longitudinal Aging Study Amsterdam, a longitudinal cohort study including 1,509 community-dwelling older persons (Study 1) and from a separate fall prevention study with 564 older persons after a fall (Study 2). Time to the first fall after inclusion and number of falls in the first year after inclusion were the primary endpoints. both in Study 1 and Study 2 the use of SBs was associated with time to the first fall, hazard ratio (HR) 1.62 (95% CI: 1.03-2.56) and HR 1.64 (95% CI: 1.19-2.26),respectively. LBs were not significantly associated with time to first fall, HR 1.40 (0.85-2.31) and HR 1.08 (0.72-1.62). In both studies, the use of SBs was also associated with number of falls, odds ratio (OR) 1.28 (95% CI: 1.01-1.61) and OR 1.37 (95% CI: 1.10-1.70). LBs were not significantly associated with number of falls, OR 1.23 (0.96-1.57) and 1.10 (0.82-1.48). the use of SBs is not associated with a lower fall risk compared with LBs. The use of both SBs and LBs by old persons should be strongly discouraged.

  6. Improving the control of systematic uncertainties in precision measurements of radionuclide half-life

    International Nuclear Information System (INIS)

    Towers, S.

    2013-01-01

    Many experiments designed to precisely determine the half-life of a radionuclide employ a long lived reference source to help determine the impact on the data of any systematic variation in the detector and associated electronics. The half-life of the radionuclide of interest is determined from the ratio of its decay rate data to the decay rate data from the reference source. This correction procedure assumes that any underlying systematic affects the data and reference measurements in exactly the same way. In this paper we show that when some systematic effects affect the two differently, the ratio procedure can leave artifacts in the corrected data that can compromise an unbiased and precise assessment of the radionuclide half-life. We describe two methods that can help overcome this problem. We also describe several statistical tests that help determine which effects may underlie systematic variations in the data. We discuss an illustrative example based on previously published 32 Si and 36 Cl data recorded by an experiment at Brookhaven National Laboratory. We correct the data for systematic variation related to climate variation and estimate the 32 Si half-life to be T 1/2 =171.8±1.8. The reduction in uncertainty in the 32 Si half-life, relative to the previous estimate based upon this data, is equivalent to that which would be achieved through increasing the size of the data set by almost 3.5 times. - Author-Highlights: • Isotope decay data and reference source data can have differing systematics. • Differing systematics can inflate uncertainty of isotope half-life estimate. • We describe two methods to overcome this problem. • We describe statistical tests to determine which variables cause systematics. • We analyze Brookhaven 32Si/36Cl decay data as an illustrative example

  7. Precision half-life measurement of 11C: The most precise mirror transition F t value

    Science.gov (United States)

    Valverde, A. A.; Brodeur, M.; Ahn, T.; Allen, J.; Bardayan, D. W.; Becchetti, F. D.; Blankstein, D.; Brown, G.; Burdette, D. P.; Frentz, B.; Gilardy, G.; Hall, M. R.; King, S.; Kolata, J. J.; Long, J.; Macon, K. T.; Nelson, A.; O'Malley, P. D.; Skulski, M.; Strauss, S. Y.; Vande Kolk, B.

    2018-03-01

    Background: The precise determination of the F t value in T =1 /2 mixed mirror decays is an important avenue for testing the standard model of the electroweak interaction through the determination of Vu d in nuclear β decays. 11C is an interesting case, as its low mass and small QE C value make it particularly sensitive to violations of the conserved vector current hypothesis. The present dominant source of uncertainty in the 11CF t value is the half-life. Purpose: A high-precision measurement of the 11C half-life was performed, and a new world average half-life was calculated. Method: 11C was created by transfer reactions and separated using the TwinSol facility at the Nuclear Science Laboratory at the University of Notre Dame. It was then implanted into a tantalum foil, and β counting was used to determine the half-life. Results: The new half-life, t1 /2=1220.27 (26 ) s, is consistent with the previous values but significantly more precise. A new world average was calculated, t1/2 world=1220.41 (32 ) s, and a new estimate for the Gamow-Teller to Fermi mixing ratio ρ is presented along with standard model correlation parameters. Conclusions: The new 11C world average half-life allows the calculation of a F tmirror value that is now the most precise value for all superallowed mixed mirror transitions. This gives a strong impetus for an experimental determination of ρ , to allow for the determination of Vu d from this decay.

  8. The impact of extended half-life versus conventional factor product on hemophilia caregiver burden.

    Science.gov (United States)

    Schwartz, Carolyn E; Powell, Victoria E; Su, Jun; Zhang, Jie; Eldar-Lissai, Adi

    2018-05-01

    Extended half-life factor products have reduced annualized bleeding rates in hemophilia patients. The impact of extended half-life versus conventional factor products on hemophilia caregiver burden has not been investigated. This study aimed to evaluate caregiver burden in extended half-life versus conventional factor products for hemophilia A and B. This cross-sectional web-based study of caregivers of people with hemophilia A or B was recruited from a panel research company and by word of mouth. Participants completed the Hemophilia Caregiver Impact measure, the PedsQL Family Impact Module (PedsQL), and the Work Productivity and Activity Impairment Questionnaire (WPAI). We also collected demographic, insurance coverage, and medical information related to the hemophilia patient(s). Burden differences were assessed using linear regression and matched cohort analyses. The sample (n = 448) included 49 people who were caring for people on extended half-life factor products. Worse caregiver burden was associated with more infusions per week and more bleeds in the past 6 months. Regression analyses suggested that caring for someone who is on a extended half-life factor product is associated with lower emotional impact (β = - 0.11, p factor product had lower Emotional Impact and Practical Impact scores (t = - 2.95 and - 2.94, respectively, p factor product infusions of extended half-life factor products appears to reduce the emotional distress and practical burden of caregiving. Future work should evaluate the longitudinal impact.

  9. Determination of half life of tellurium isotopes: a proposal for the teaching of nuclear physics

    International Nuclear Information System (INIS)

    Ruivo, Julio C.; Zamboni, Cibele B.; Batista, Wagner F.

    2013-01-01

    This work aimed at the development of courseware for teaching nuclear physics, using experimental data of half-life measurement (T1/2) of Tellurium isotopes (A=127 and 131). The choice of Tellurium was established for providing nuclear data, which are fundamental in related investigations of nuclear structure and its use in various areas such as geochemistry, chemical and pharmaceutical industries, astrophysics etc. For evaluation of the proposal performance, the material was made available, bringing a lot of information about nuclear safety, production and storage of radioactive material and concepts of radioactive decay, subatomic particles, emission of gamma radiation, half-life, etc.

  10. Determination of half life of tellurium isotopes: a proposal for the teaching of nuclear physics

    Energy Technology Data Exchange (ETDEWEB)

    Ruivo, Julio C.; Zamboni, Cibele B.; Batista, Wagner F., E-mail: julio.ruivo.costa@usp.br, E-mail: czamboni@ipen.br, E-mail: fisicawagner@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    This work aimed at the development of courseware for teaching nuclear physics, using experimental data of half-life measurement (T1/2) of Tellurium isotopes (A=127 and 131). The choice of Tellurium was established for providing nuclear data, which are fundamental in related investigations of nuclear structure and its use in various areas such as geochemistry, chemical and pharmaceutical industries, astrophysics etc. For evaluation of the proposal performance, the material was made available, bringing a lot of information about nuclear safety, production and storage of radioactive material and concepts of radioactive decay, subatomic particles, emission of gamma radiation, half-life, etc.

  11. Application of genetic algorithms for determination biological half-life of 137 Cs in milk

    International Nuclear Information System (INIS)

    Pantelic, G.

    1998-01-01

    Genetic algorithm an optimization method involving natural selection mechanisms, was used to determine biological half-life of sup 1 sup 3 sup 7 Cs in the milk, after the Chernobyl accident, based on a two compartment linear system model. Genetic algorithms operate on populations of strings. Reproduction, crossover and mutation are applied to successive string population to create new string population. A model parameter estimation is performed by minimizing square differences between fitting function and experimental data. The calculated biological half-life of sup 1 sup 3 sup 7 Cs in milk is (32(+(-) days (author)

  12. Study of the half-life of 123I and the determination of possible radionuclidic impurities

    International Nuclear Information System (INIS)

    Delgado, Jose Ubiratan; Araujo, Miriam Taina Ferreira de; Silva, Carlos Jose da; Araujo, Camila Cristina Cunha; Candido, Marcos Antonio; Pereira, Wagner do Prado

    2013-01-01

    During the process of production of the radiopharmaceutical nuclear reactor or cyclotron, impurities can be generated from biological, chemical and radionuclidic. The development of the present work was to study the half-life of Na 123 I sample produced in IEN (Institute of Nuclear Engineering) using the technique of gamma-ray spectrometry with germanium detector in order to Identify such impurities. The results Indicate values of half-life consistent with recent publications with a deviation of 0,08% and 0:11% of uncertainty as well as the identification of impurities to radionuclides 95m Tc, 96 Tc and 121 Te. (author)

  13. Dual Constant Domain-Fab: A novel strategy to improve half-life and potency of a Met therapeutic antibody.

    Science.gov (United States)

    Cignetto, Simona; Modica, Chiara; Chiriaco, Cristina; Fontani, Lara; Milla, Paola; Michieli, Paolo; Comoglio, Paolo M; Vigna, Elisa

    2016-06-01

    The kinase receptor encoded by the Met oncogene is a sensible target for cancer therapy. The chimeric monovalent Fab fragment of the DN30 monoclonal antibody (MvDN30) has an odd mechanism of action, based on cell surface removal of Met via activation of specific plasma membrane proteases. However, the short half-life of the Fab, due to its low molecular weight, is a severe limitation for the deployment in therapy. This issue was addressed by increasing the Fab molecular weight above the glomerular filtration threshold through the duplication of the constant domains, in tandem (DCD-1) or reciprocally swapped (DCD-2). The two newly engineered molecules showed biochemical properties comparable to the original MvDN30 in vitro, acting as full Met antagonists, impairing Met phosphorylation and activation of downstream signaling pathways. As a consequence, Met-mediated biological responses were inhibited, including anchorage-dependent and -independent cell growth. In vivo DCD-1 and DCD-2 showed a pharmacokinetic profile significantly improved over the original MvDN30, doubling the circulating half-life and reducing the clearance. In pre-clinical models of cancer, generated by injection of tumor cells or implant of patient-derived samples, systemic administration of the engineered molecules inhibited the growth of Met-addicted tumors. Copyright © 2016 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  14. An improved method for determination of technetium-99m half-life for the quality assurance procedures of radiopharmaceuticals

    International Nuclear Information System (INIS)

    Abd Jalil Abd Hamid; Juhari Mohd Yusof; Zakaria Ibrahim; Wan Mohd Ferdaus Wan Ishak; Mohamad Hafiz Ahmad

    2009-01-01

    An improve method for identity tests of technetium-99m for the quality assurance procedures are presented. Computerized methods based on the least-squares of decay curve fitting for half-life estimation of technetium-99m was tested. Thus, least-squares method was employ as a decay curve fitting procedures in our software. Theoretical calculated half-life of technetium-99m for evaluation was performed for comparison. In Fig. 3 is shown, the decay curve fitting of a sample over one second counting time interval. The R2 value of the curve suggests that the time of the study was too short to obtain acceptable value. A similar measurement for another data set was done for a longer period of time and in Table 1 is shown a representative decay curve fitting. The value was found to be 6.006 hours with a discrepancy of -0.28% from the value taken from the literature. The value is in agreement with the literature for time interval greater than 2 seconds. The results obtained by this method show that the used of least-squares method for decay curve fitting are appropriate for routine identity tests. This confirmed that the least-squares method applied in our decay curve fitting software are remarkably improved and convenient for routine identity tests purposes. (Author)

  15. Glucagon-like Peptide 1 Conjugated to Recombinant Human Serum Albumin Variants with Modified Neonatal Fc Receptor Binding Properties. Impact on Molecular Structure and Half-Life

    DEFF Research Database (Denmark)

    Bukrinski, Jens T.; Sønderby, Pernille; Antunes, Filipa

    2017-01-01

    Glucagon-like peptide 1 (GLP-1) is a small incretin hormone stimulated by food intake, resulting in an amplification of the insulin response. Though interesting as a drug candidate for the treatment of type 2 diabetes mellitus, its short plasma half-life of less than 3 minutes limits its clinical...... use. A strategy to extend the half-life of GLP-1 utilizes the long half-life of human serum albumin (HSA) by combining the two via chemical conjugation or genetic fusion. HSA has a plasma half-life of around 21 days owing to its interaction with the neonatal Fc receptor (FcRn) expressed in endothelial...... with the available structural information on the FcRn and GLP-1 receptor (GLP-1R) obtained from X-ray crystallography, we can explain the observed in-vitro and in-vivo behaviour. We conclude that the conjugation of GLP-1 to rHSA does not affect the interaction between rHSA and FcRn, while the observed decrease...

  16. Focus on the legislative approach to short half life radioactive hospital waste releasing.

    Science.gov (United States)

    Petrucci, Caterina; Traino, Antonio Claudio

    2015-11-01

    We propose to summarize the advancements introduced by the new Directive 2013/59/Euratom concerning the concept of clearance, for which the radioactive medical waste represents a typical candidate. We also intend to spotlight disputable points in the regulatory scheme in force in Italy, as well to make a contribution to evaluate whether the practice of patients' urine storing, stated by it, can be regarded to be proper. With directing our interest to radionuclides used in Nuclear Medicine, we first present an overview of how the clearance concept, and that of exemption closely related to it, have been developed from the previous Directive 96/29 to the new one; then we describe the implementation of these concepts in the Italian legislation. Subsequently we estimate the exposure due both to keeping the effluent on site and to direct discharging it to the environment. In line with a well established international consensus, the Directive 2013/59 drives simple and harmonized regulation of clearance. On the contrary, some complexity and lack of consistency can be found in the framework of the national legislation affecting the radioactive medical waste handling. In addition the practice of excreta storing is disputed not to be really beneficial. The opportunity should be taken to make the whole system of these requirements simpler and more consistent and effective when it is revised to transpose the new Directive. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  17. Endogenous compounds labeled with radionuclides of short half-life-some perspectives

    DEFF Research Database (Denmark)

    Roland Långström, Bengt; Karimi, F; Watanabe, Y

    2013-01-01

    In the article, the strategy and synthesis of some endogenous compounds labeled mainly with (11) C are presented. There are some examples illustrating how endogenous labeled compounds in connection with positron emission tomography have unique properties to describe various biological processes......, and a few examples of the use of tracers labeled with (13) N and (15) O are also discussed. Labeled endogenous compounds may be an important asset to describe the conditions and the status of biological systems and might therefore be a key for the future search of individualized medicine....

  18. Automated spectrometer interface for measurement of short half-life samples for neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lapolli, André L.; Secco, Marcello; Genezini, Frederico A.; Zahn, Guilherme S.; Moreira, Edson G., E-mail: alapolli@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    In this paper a source positioning system was developed, based on a HPGe detector coupled to a Canberra DAS 1000 data acquisition system and Canberra's GENIE2K software and libraries. The system is composed of a step motor coupled to an Arduino Uno microcontroller, which is programmed using C language to allow for a source-detector distance between 0.3 and 20 cm - both components are coupled to a PC computer using the USB interface. In order to allow automated data acquisition, two additional pieces of software were developed. The first one, a Human-Machine Interface (HMI) programmed in Visual Basic 6, allows the programming and monitoring of the data acquisition process, and the other, in REXX language, controls the data acquisition process in the background. The HMI is user-friendly and versatile, so that the even rather complex data acquisition processes may be easily programmed. When the experiment scheme is saved, two files are created and used by the REXX code to control the acquisition process so that the data acquisition is automatically stopped and saved after a user-defined time, then the source is repositioned and data acquisition is cleared and restarted. While in the present stage the system only offers three distinct source positions, finer source-position adjusting is under development. In its present configuration the system has been tested for stability and repeatability in all three positions, with an an excellent performance (author)

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

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

    Science.gov (United States)

    Bray, Lane A.; Ryan, Jack L.

    1998-01-01

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

  1. Automated spectrometer interface for measurement of short half-life samples for neutron activation analysis

    International Nuclear Information System (INIS)

    Lapolli, André L.; Secco, Marcello; Genezini, Frederico A.; Zahn, Guilherme S.; Moreira, Edson G.

    2017-01-01

    In this paper a source positioning system was developed, based on a HPGe detector coupled to a Canberra DAS 1000 data acquisition system and Canberra's GENIE2K software and libraries. The system is composed of a step motor coupled to an Arduino Uno microcontroller, which is programmed using C language to allow for a source-detector distance between 0.3 and 20 cm - both components are coupled to a PC computer using the USB interface. In order to allow automated data acquisition, two additional pieces of software were developed. The first one, a Human-Machine Interface (HMI) programmed in Visual Basic 6, allows the programming and monitoring of the data acquisition process, and the other, in REXX language, controls the data acquisition process in the background. The HMI is user-friendly and versatile, so that the even rather complex data acquisition processes may be easily programmed. When the experiment scheme is saved, two files are created and used by the REXX code to control the acquisition process so that the data acquisition is automatically stopped and saved after a user-defined time, then the source is repositioned and data acquisition is cleared and restarted. While in the present stage the system only offers three distinct source positions, finer source-position adjusting is under development. In its present configuration the system has been tested for stability and repeatability in all three positions, with an an excellent performance (author)

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

    Science.gov (United States)

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

    1999-03-23

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

  3. Intrinsically Disordered Segments Affect Protein Half-Life in the Cell and during Evolution

    Directory of Open Access Journals (Sweden)

    Robin van der Lee

    2014-09-01

    Full Text Available Precise control of protein turnover is essential for cellular homeostasis. The ubiquitin-proteasome system is well established as a major regulator of protein degradation, but an understanding of how inherent structural features influence the lifetimes of proteins is lacking. We report that yeast, mouse, and human proteins with terminal or internal intrinsically disordered segments have significantly shorter half-lives than proteins without these features. The lengths of the disordered segments that affect protein half-life are compatible with the structure of the proteasome. Divergence in terminal and internal disordered segments in yeast proteins originating from gene duplication leads to significantly altered half-life. Many paralogs that are affected by such changes participate in signaling, where altered protein half-life will directly impact cellular processes and function. Thus, natural variation in the length and position of disordered segments may affect protein half-life and could serve as an underappreciated source of genetic variation with important phenotypic consequences.

  4. Radionuclide biological half-life values for terrestrial and aquatic wildlife

    International Nuclear Information System (INIS)

    Beresford, N.A.; Beaugelin-Seiller, K.; Burgos, J.; Cujic, M.; Fesenko, S.; Kryshev, A.; Pachal, N.; Real, A.; Su, B.S.; Tagami, K.; Vives i Batlle, J.; Vives-Lynch, S.; Wells, C.; Wood, M.D.

    2015-01-01

    The equilibrium concentration ratio is typically the parameter used to estimate organism activity concentrations within wildlife dose assessment tools. Whilst this is assumed to be fit for purpose, there are scenarios such as accidental or irregular, fluctuating, releases from licensed facilities when this might not be the case. In such circumstances, the concentration ratio approach may under- or over-estimate radiation exposure depending upon the time since the release. To carrying out assessments for such releases, a dynamic approach is needed. The simplest and most practical option is representing the uptake and turnover processes by first-order kinetics, for which organism- and element-specific biological half-life data are required. In this paper we describe the development of a freely available international database of radionuclide biological half-life values. The database includes 1907 entries for terrestrial, freshwater, riparian and marine organisms. Biological half-life values are reported for 52 elements across a range of wildlife groups (marine = 9, freshwater = 10, terrestrial = 7 and riparian = 3 groups). Potential applications and limitations of the database are discussed. - Highlights: • 1907 biological half-life values have been collated for wildlife species. • Data cover 52 elements. • 27 marine, freshwater, riparian and terrestrial organisms are included.

  5. Intrinsically disordered segments and the evolution of protein half-life

    Science.gov (United States)

    Babu, M.

    2013-03-01

    Precise turnover of proteins is essential for cellular homeostasis and is primarily mediated by the proteasome. Thus, a fundamental question is: What features make a protein an efficient substrate for degradation? Here I will present results that proteins with a long terminal disordered segment or internal disordered segments have a significantly shorter half-life in yeast. This relationship appears to be evolutionarily conserved in mouse and human. Furthermore, upon gene duplication, divergence in the length of terminal disorder or variation in the number of internal disordered segments results in significant alteration of the half-life of yeast paralogs. Many proteins that exhibit such changes participate in signaling, where altered protein half-life will likely influence their activity. We suggest that variation in the length and number of disordered segments could serve as a remarkably simple means to evolve protein half-life and may serve as an underappreciated source of genetic variation with important phenotypic consequences. MMB acknowledges the Medical Research Council for funding his research program.

  6. Safety and Efficacy of BAY 94-9027, a Prolonged-Half-Life Factor VIII

    DEFF Research Database (Denmark)

    Reding, M T; Ng, H J; Poulsen, Lone Hvitfeldt

    2017-01-01

    BACKGROUND: BAY 94-9027 is a B-domain-deleted prolonged-half-life recombinant factor VIII (FVIII) conjugates in a site-specific manner with polyethylene glycol. OBJECTIVE: Assess efficacy and safety of BAY 94-9027 for prophylaxis and treatment of bleeds in patients with severe hemophilia A PATIEN...

  7. Effect of parent and daughter deformation on half-life time in exotic ...

    Indian Academy of Sciences (India)

    Shi and Swiatecki [6] put forward a model for exotic decay studies that uses Coulomb and proximity potential as interacting barrier for post-scission region and uses simple power law for overlap region. These authors [7] studied the effect of deformation of parent, daughter and shell attenuation on half-life time treating ...

  8. Dependence of the half-life of 221Fr on the implantation environment

    DEFF Research Database (Denmark)

    Olaizola, B.; Fraile, L.M.; Riisager, Karsten

    2010-01-01

    The possible dependence of the half-life of 221Fr on the solid-state environment has been investigated by the simultaneous measurement of implanted 221Fr ions in an insulator (Si) and a metallic substrate (Au) at the ISOLDE facility at CERN. Our results indicate that, if existing, the difference ...

  9. Precision half-life measurement of .sup.140 La with Ge-detector

    Czech Academy of Sciences Publication Activity Database

    Adam, Jindřich; Belov, A. G.; Brandt, R.; Chaloun, P.; Honusek, Milan; Kalinnikov, V. G.; Krivopustov, M. I.; Kulakov, B. A.; Langrock, E. J.; Pronskikh, V. S.; Sosnin, A. N.; Stegailov, V. I.; Tsoupko-Sitnikov, V. M.; Wan, J. S.; Westmeier, W.

    2002-01-01

    Roč. 187, - (2002), s. 419-426 ISSN 0168-583X R&D Projects: GA AV ČR KSK1048102 Keywords : radioastive nuclei * Ge-detectors * half-life measurements Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.158, year: 2002

  10. Lithium as an adjunct to radioiodine therapy in Graves' disease for prolonging the intrathyroidal effective half-life of radioiodine. Useful or not?

    Energy Technology Data Exchange (ETDEWEB)

    Dunkelmann, S.; Kuenstner, H.; Nabavi, E.; Eberlein, U.; Groth, P.; Schuemichen, C. [Rostock Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin, Zentrum fuer Radiologie

    2006-07-01

    Aim: Evaluation of intrathyroidal kinetics of radioiodine with and without lithium as adjunct with respect to the increase in radiation dose delivered to the thyroid. Patients, methods: 267 patients in three groups were included in the study. Group I with 227 patients served as control group, Group II with 21 patients and Group III with 19 patients were distinguished by an intrathyroidal half-life of radioiodine below 3.5 days in the diagnostic test. Patients in Group III received 885 mg lithium carbonate a day for 2 weeks as adjunct to radioiodine therapy. Both diagnostic and therapeutic radioiodine kinetics were followed up by at least 10 uptake measurements within a minimum of 48 h. Kinetics of radioiodine were defined mathematically as balance of the thyroidal iodine intake and excretion by a two-compartment model. Results: Under therapy the maximum uptake of radioiodine was reduced by nearly 10% in all groups, in Group I, the effective half-life as well as the product of maximum uptake x effective half-life as an equivalent of radiation dose independent of thyroid volume was lowered in the same magnitude. In Group II, the energy-dose equivalent remained constant under therapy. With adjunct lithium in Group III, the effective half-life was prolonged significantly by factor 1.61{+-}0.49 and the volume-independent energy-dose equivalent by factor 1.39{+-}0.37. No severe side effects of lithium were observed. Conclusion: Using lithium as adjunct to radio-iodine therapy increases the radiation dose delivered to the thyroid by 39% on average and nearly 30% of radioiodine activity can be saved in these patients. Lithium is recommended in patients with very short effective half-life in the diagnostic test in order to reduce the activity required and whole-body radiation dose. (orig.)

  11. On the half-life of luminescence signals in dosimetric applications: A unified presentation

    Science.gov (United States)

    Pagonis, V.; Kitis, G.; Polymeris, G. S.

    2018-06-01

    Luminescence signals from natural and man-made materials are widely used in dosimetric and dating applications. In general, there are two types of half-lives of luminescence signals which are of importance to experimental and modeling work in this research area. The first type of half-life is the time required for the population of the trapped charge in a single trap to decay to half its initial value. The second type of half-life is the time required for the luminescence intensity to drop to half of its initial value. While there a handful of analytical expressions available in the literature for the first type of half-life, there are no corresponding analytical expressions for the second type. In this work new analytical expressions are derived for the half-life of luminescence signals during continuous wave optical stimulation luminescence (CW-OSL) or isothermal luminescence (ITL) experiments. The analytical expressions are derived for several commonly used luminescence models which are based on delocalized transitions involving the conduction band: first and second order kinetics, empirical general order kinetics (GOK), mixed order kinetics (MOK) and the one-trap one-recombination center (OTOR) model. In addition, half-life expressions are derived for a different type of luminescence model, which is based on localized transitions in a random distribution of charges. The new half-life expressions contain two parts. The first part is inversely proportional to the thermal or optical excitation rate, and depends on the experimental conditions and on the cross section of the relevant luminescence process. The second part is characteristic of the optical and/or thermal properties of the material, as expressed by the parameters in the model. A new simple and quick method for analyzing luminescence signals is developed, and examples are given of applying the new method to a variety of dosimetric materials. The new test allows quick determination of whether a set of

  12. Validation of effective half-life of tritium and computation of dose at Madras Atomic Power Station

    International Nuclear Information System (INIS)

    Moolya, L.L.; Kannan, R.K.; Sreekumaran Nair, B.; Mohandas, P.G.; Rajan, R.

    2001-01-01

    In Pressurised Heavy Water Reactors (PHWRs) tritium is produced by the activation of deuterium present in the moderator and coolant system. Hence, the inventory of tritium in PHWR is high and it contributes about 20 percent of the Station Dose. Tritium enters body by inhalation, ingestion and skin absorption. Dose received by an individual depends on its elimination rate from the body and hence the effective half-life. It is found that the effective half-life varies from person to person. The effective half-life also depends on the weather condition. The variation of effective half-life is taken care of in dose estimation by average method. However, in case of dose calculation for single uptake cases, there is a need to take fixed effective half-life. ICRP has taken the effective half-life as 10 days. The effective half-life is taken as 6 days in Indian conditions based on the studies conducted earlier in MAPS and elsewhere. Now with available data for about 16 years a fresh study was conducted to validate the effective half-life. This paper gives the study of effective half-life of tritium and its variation during different seasons of the year in MAPS. This paper also gives methods used for computing dose due to tritium. (author)

  13. A half-life the divided life of Bruno Pontecorvo, physicist or spy

    CERN Document Server

    Close, Frank

    2015-01-01

    Bruno Pontecorvo dedicated his career to hunting for the Higgs boson of his day: the neutrino, a nearly massless particle considered essential to the process of nuclear fission. His work on the Manhattan project under Enrico Fermi confirmed his reputation as a brilliant physicist and helped usher in the nuclear age. He should have won a Nobel Prize, but late in the summer of 1950 he vanished. At the height of the Cold War, Pontecorvo had disappeared behind the Iron Curtain. In Half-Life, physicist and historian Frank Close offers a heretofore untold history of Pontecorvo’s life, based on unprecedented access to his friends, family, and colleagues. With all the elements of a Cold War thriller—classified atomic research, an infamous double agent, a kidnapping by Soviet operatives—Half-Life is a history of particle physics at perhaps its most powerful: when it created the bomb.

  14. Determination of {sup 126}Sn half-life from ICP-MS and gamma spectrometry measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bienvenu, P.; Arnal, N.; Comte, J. [CEA Cadarache DEN/DEC/SA3C/LARC, Paul Lez Durance (France); Ferreux, L.; Lepy, M.C.; Be, M.M. [CEA Saclay LIST LNE/LNHB, Gif sur Yvette (France); Andreoletti, G. [AREVA Cogema SL/UP2-800, Beaumont Hague (France)

    2009-07-01

    A new value of {sup 126}Sn half-life was determined by combination of inductively coupled plasma-mass spectrometry (ICP-MS) and gamma spectrometry measurements on purified sample solutions collected from nuclear fuel reprocessing. {sup 126}Sn was isolated through dissolution of fission product precipitates and liquid-liquid extraction with N-benzoyl-N-phenyl-hydroxylamine (BPHA). The abundance of {sup 126}Sn atoms together with the absence of interfering species in the analysed solutions made it possible to measure both mass concentration and nuclide activity with high precision and accuracy. This led to a {sup 126}Sn half-life value of 1.980 (57) x 10{sup 5} a. (orig.)

  15. High-Precision Half-Life Measurement for the Superallowed β+ Emitter Alm26

    Science.gov (United States)

    Finlay, P.; Ettenauer, S.; Ball, G. C.; Leslie, J. R.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Bandyopadhyay, D.; Cross, D. S.; Demand, G.; Djongolov, M.; Garrett, P. E.; Green, K. L.; Grinyer, G. F.; Hackman, G.; Leach, K. G.; Pearson, C. J.; Phillips, A. A.; Sumithrarachchi, C. S.; Triambak, S.; Williams, S. J.

    2011-01-01

    A high-precision half-life measurement for the superallowed β+ emitter Alm26 was performed at the TRIUMF-ISAC radioactive ion beam facility yielding T1/2=6346.54±0.46stat±0.60systms, consistent with, but 2.5 times more precise than, the previous world average. The Alm26 half-life and ft value, 3037.53(61) s, are now the most precisely determined for any superallowed β decay. Combined with recent theoretical corrections for isospin-symmetry-breaking and radiative effects, the corrected Ft value for Alm26, 3073.0(12) s, sets a new benchmark for the high-precision superallowed Fermi β-decay studies used to test the conserved vector current hypothesis and determine the Vud element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix.

  16. High-Precision Half-life Measurements for the Superallowed β+ Emitter 14O

    Science.gov (United States)

    Laffoley, A. T.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Blank, B.; Bouzomita, H.; Cross, D. S.; Diaz Varela, A.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Giovinazzo, J.; Grinyer, G. F.; Hackman, G.; Hadinia, B.; Jamieson, D. S.; Ketelhut, S.; Leach, K. G.; Leslie, J. R.; Tardiff, E. R.; Thomas, J. C.; Unsworth, C.

    2014-03-01

    The half-life of 14O, a superallowed Fermi β+ emitter, has been determined via simultaneous γ and β counting experiments at TRIUMF's Isotope Separator and Accelerator facility. Following the implantation of 14O samples at the center of the 8π spectrometer, a γ counting measurement was performed by detecting the 2313 keV γ-rays emitted from the first excited state of the daughter 14N using 20 high-purity germanium (HPGe) detectors. A simultaneous β counting experiment was performed using a fast plastic scintillator positioned directly behind the implantation site. The results, T½(γ) = 70:632 ± 0:094 s and T½(β) = 70:610 ± 0:030 s, are consistent with one another and, together with eight previous measurements, establish a new average for the 14O half-life of T½ = 70:619 ± 0:011 s with a reduced χ2 of 0.99.

  17. Half-life and intensities of photons of 103Pd isotope

    International Nuclear Information System (INIS)

    Popov, Yu.S.; Zakharova, L.V.; Kupriyanov, V.N.; Andreev, O.I.; Pakhomov, A.N.; Vakhetov, F.Z.

    2001-01-01

    Half-life and intensities of photons forming during 103 Pd isotope decay are determined by the methods of semiconductor x-ray and γ-spectrometry. 103 Pd is applied in nuclear medicine for preparation of 103m Rh isomer (T 1/2 =56 min) being used in irradiation of prostate neoplasms. Half-life of 103 Pd isotope is 16±0.6 days, relative intensities of x-ray and γ-photons are: K α /Kβ=5.1±0.4; 358 keV - 100 rel.units; 295 keV - 12.3±0.4 rel.units; 497 keV - 17.6±0.6 rel.units. Errors are represented for confidence probability 95 % [ru

  18. A New Method to Determine the Half-Life for Penicillin Using Microcalorimeter

    Science.gov (United States)

    Li, Z. X.; Zhao, W. W.

    2015-01-01

    The dissolution process of penicillin in normal saline and isotonic glucose solution was reported using a microcalorimeter. Both the integral and differential heats of solution were measured. The quantitative relationships between the amount of heat released and the quantity of dissolved penicillin were established. Meanwhile, the kinetics and the half-life of the dissolution processes as well as the enthalpy of solution, the entropy of dissolution, and the free energy of dissolution were determined. The results showed that a change of the solvent from normal saline to isotonic glucose solution had little effect on the half-life of penicillin in the dissolution process, and there was no significant difference between the stabilities of penicillin in isotonic glucose solution and normal saline. Moreover, the dissolution process of penicillin in isotonic glucose solution followed the first-order kinetics. These results could provide a theoretical basis for the clinical applications of penicillin.

  19. Biological half-life of radiophosphorus in desert locust, Schistocerca gregaria Forskal (orthoptera:acrididae)

    International Nuclear Information System (INIS)

    Ulagaraj, S.M.; Singh, K.M.; Sethi, G.R.

    1975-01-01

    Adult desert locust, Schistocerca gregaria Forskal were fed with cabbage leaves, painted with carrier free 32 P 1mCi/ml. Radioactivity of five adults of both sexes and of feces was measured daily for 28 days. The amount of radioactivity appearing in the feces of males was consistently below that found in female locusts. The mean biological half-life of 32 P for males and females were 35.04 and 15.01 days, respectively. (author)

  20. Neutron activation analyses and half-life measurements at the usgs triga reactor

    Science.gov (United States)

    Larson, Robert E.

    Neutron activation of materials followed by gamma spectroscopy using high-purity germanium detectors is an effective method for making measurements of nuclear beta decay half-lives and for detecting trace amounts of elements present in materials. This research explores applications of neutron activation analysis (NAA) in two parts. Part 1. High Precision Methods for Measuring Decay Half-Lives, Chapters 1 through 8 Part one develops research methods and data analysis techniques for making high precision measurements of nuclear beta decay half-lives. The change in the electron capture half-life of 51Cr in pure chromium versus chromium mixed in a gold lattice structure is explored, and the 97Ru electron capture decay half-life are compared for ruthenium in a pure crystal versus ruthenium in a rutile oxide state, RuO2. In addition, the beta-minus decay half-life of 71mZn is measured and compared with new high precision findings. Density Functional Theory is used to explain the measured magnitude of changes in electron capture half-life from changes in the surrounding lattice electron configuration. Part 2. Debris Collection Nuclear Diagnostic at the National Ignition Facility, Chapters 9 through 11 Part two explores the design and development of a solid debris collector for use as a diagnostic tool at the National Ignition Facility (NIF). NAA measurements are performed on NIF post-shot debris collected on witness plates in the NIF chamber. In this application NAA is used to detect and quantify the amount of trace amounts of gold from the hohlraum and germanium from the pellet present in the debris collected after a NIF shot. The design of a solid debris collector based on material x-ray ablation properties is given, and calculations are done to predict performance and results for the collection and measurements of trace amounts of gold and germanium from dissociated hohlraum debris.

  1. Precise half-life measurement of the superallowed β+ emitter 38Km

    International Nuclear Information System (INIS)

    Ball, G. C.; Boisvert, G.; Bricault, P.; Churchman, R.; Dombsky, M.; Lindner, T.; Macdonald, J. A.; Vandervoort, E.; Bishop, S.; D'Auria, J. M.; Hardy, J. C.; Iacob, V. E.; Leslie, J. R.; Mak, H.-B.

    2010-01-01

    The half-life of 38 K m has been measured to be 924.46(14) ms, a result that is a factor of two more precise than any of the five previous measurements of this quantity. The previous results are not consistent with one another, but our result agrees well with the two most recent ones. The derived ft value for 38 K m is now one of the three most precisely known superallowed ft values.

  2. Increased Functional Half-life of Fibroblast Growth Factor-1 by Recovering a Vestigial Disulfide Bond

    Directory of Open Access Journals (Sweden)

    Jihun Lee

    2010-12-01

    Full Text Available The fibroblast growth factor (FGF family of proteins contains an absolutely conserved Cys residue at position 83 that is present as a buried free cysteine. We have previously shown that mutation of the structurally adjacent residue, Ala66, to cysteine results in the formation of a stabilizing disulfide bond in FGF-1. This result suggests that the conserved free cysteine residue at position 83 in the FGF family of proteins represents a vestigial half-cystine. Here, we characterize the functional half-life and mitogenic activity of the oxidized form of the Ala66Cys mutation to identify the effect of the recovered vestigial disulfide bond between Cys83 and Cys66 upon the cellular function of FGF-1. The results show that the mitogenic activity of this mutant is significantly increased and that its functional half-life is greatly extended. These favorable effects are conferred by the formation of a disulfide bond that simultaneously increases thermodynamic stability of the protein and removes a reactive buried thiol at position 83. Recovering this vestigial disulfide by introducing a cysteine at position 66 is a potentially useful protein engineering strategy to improve the functional half-life of other FGF family members.

  3. Measurements of Actual Effective Half - Life in 131I Therapy for Graves' Hyperthyroidism

    International Nuclear Information System (INIS)

    So, Yong Seon; Kim, Myung Seon; Kwon, Ki Hyun; Kim, Seok Whan; Kim, Tae Hyung; Han, Sang Woong; Kim, Eun Sil; Kim, Chong Soon

    1996-01-01

    Radioiodine[131I] has been used for the treatment of Graves' hyperthyroidism since the late 1940's and is now generally regarded as the treatment of choice for Graves' hyperthyroidism who does not remit following a course of antithyroid drugs. But for the dose given, several different protocols have been described by different centers, each attempting to reduce the incidence of long-term hypothyroidism while maintaining an acceptable rate control of Graves' hyperthyroidism. Our goals were to evaluate effective half-life and predict absorbed dose in Graves' hyperthyroidism patients, therefore, to calculate and read minister radioiodine activity needed to achieve aimed radiation dose. Our data showed that the mean effective 131I half-life for Graves' disease is 5.3 days(S.D=0.88) and mean biologic half-life is 21 days, range 9.5-67.2 days. The mean administered activity and the mean values of absorbed doses wet: 532 MBq(S.D.=254), 112 Gy (S.D.=50.9), respectively. The mean activity needed to achieve aimed radiation dose were 51 MBq and marked differences of 131I thyroidal uptake between tracer and therapy occurred in our study. We are sure that the dose calculation method that uses 5 days thyroidal 131I uptake measurements after tracer and therapy dose, provides sufficient data about the effective treatment in Graves' hyperthyroidism.

  4. Measurements of Actual Effective Half - Life in {sup 131}I Therapy for Graves' Hyperthyroidism

    Energy Technology Data Exchange (ETDEWEB)

    So, Yong Seon; Kim, Myung Seon; Kwon, Ki Hyun; Kim, Seok Whan; Kim, Tae Hyung; Han, Sang Woong; Kim, Eun Sil; Kim, Chong Soon [Hanil General Hospital, Seoul (Korea, Republic of)

    1996-03-15

    Radioiodine[131I] has been used for the treatment of Graves' hyperthyroidism since the late 1940's and is now generally regarded as the treatment of choice for Graves' hyperthyroidism who does not remit following a course of antithyroid drugs. But for the dose given, several different protocols have been described by different centers, each attempting to reduce the incidence of long-term hypothyroidism while maintaining an acceptable rate control of Graves' hyperthyroidism. Our goals were to evaluate effective half-life and predict absorbed dose in Graves' hyperthyroidism patients, therefore, to calculate and read minister radioiodine activity needed to achieve aimed radiation dose. Our data showed that the mean effective 131I half-life for Graves' disease is 5.3 days(S.D=0.88) and mean biologic half-life is 21 days, range 9.5-67.2 days. The mean administered activity and the mean values of absorbed doses wet: 532 MBq(S.D.=254), 112 Gy (S.D.=50.9), respectively. The mean activity needed to achieve aimed radiation dose were 51 MBq and marked differences of 131I thyroidal uptake between tracer and therapy occurred in our study. We are sure that the dose calculation method that uses 5 days thyroidal 131I uptake measurements after tracer and therapy dose, provides sufficient data about the effective treatment in Graves' hyperthyroidism.

  5. A novel exendin-4 human serum albumin fusion protein, E2HSA, with an extended half-life and good glucoregulatory effect in healthy rhesus monkeys

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ling; Wang, Lin; Meng, Zhiyun; Gan, Hui; Gu, Ruolan; Wu, Zhuona; Gao, Lei; Zhu, Xiaoxia; Sun, Wenzhong; Li, Jian; Zheng, Ying; Dou, Guifang, E-mail: douguifang@vip.163.com

    2014-03-07

    Highlights: • E2HSA has an extended half-life and good plasma stability. • E2HSA could improve glucose-dependent insulin secretion. • E2HSA has excellent glucoregulatory effects in vivo. • E2HSA could potentially be used as a new long-acting GLP-1 receptor agonist for type 2 diabetes management. - Abstract: Glucagon-like peptide-1 (GLP-1) has attracted considerable research interest in terms of the treatment of type 2 diabetes due to their multiple glucoregulatory functions. However, the short half-life, rapid inactivation by dipeptidyl peptidase-IV (DPP-IV) and excretion, limits the therapeutic potential of the native incretin hormone. Therefore, efforts are being made to develop the long-acting incretin mimetics via modifying its structure. Here we report a novel recombinant exendin-4 human serum albumin fusion protein E2HSA with HSA molecule extends their circulatory half-life in vivo while still retaining exendin-4 biological activity and therapeutic properties. In vitro comparisons of E2HSA and exendin-4 showed similar insulinotropic activity on rat pancreatic islets and GLP-1R-dependent biological activity on RIN-m5F cells, although E2HSA was less potent than exendin-4. E2HSA had a terminal elimation half-life of approximate 54 h in healthy rhesus monkeys. Furthermore, E2HSA could reduce postprandial glucose excursion and control fasting glucose level, dose-dependent suppress food intake. Improvement in glucose-dependent insulin secretion and control serum glucose excursions were observed during hyperglycemic clamp test (18 h) and oral glucose tolerance test (42 h) respectively. Thus the improved physiological characterization of E2HSA make it a new potent anti-diabetic drug for type 2 diabetes therapy.

  6. Measurement of the half-life of sup 1 sup 7 sup 6 Lu

    CERN Document Server

    Nir-El, Y

    1998-01-01

    The half-life of sup 1 sup 7 sup 6 Lu was determined by measuring the disintegration rate of a solution of lutetium oxide, using a calibrated HPGe detector, and found to be (3.69+-0.02)x10 sup 1 sup 0 y. It is recommended that the current adopted value be calculated from the grouping of three published values since 1983, including our value, the weighted mean of which is (3.73+-0.01)x10 sup 1 sup 0 y.

  7. Half-life of the 3/2/sup +/ level of /sup 119/Sn

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, M C; Gil, F B [Faculdade de Ciencias da Universidade de Lisboa, Lisbon (Portugal). Grupo de Espectroscopia Nuclear, Laboratorio de Fisica

    1976-01-01

    The half-life of the 3/2/sup +/, 23.87 keV level of /sup 119/Sn is measured by the delayed coincidence technique. Magnetic spectrometry associated with scintillation techniques and scintillation spectrometry only have been used. The results obtained with these techniques were respectively Tsub(1/2) = 17.87 +- 0.11 ns and Tsub(1/2) = 18.48 +- 0.30 ns. The measured reduced M1 transition probability is compared with the single-particle and Kisslinger and Sorensen model predictions.

  8. The Half Life of the 53 keV Level in {sup 197}Pt

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G

    1967-02-15

    The half life of the recently proposed 53 keV level in {sup 197}Pt has been measured to 18.5 {+-} 1.5 nsec using the delayed coincidence technique. This level, which is identified with the f{sub 5/2} single particle state, decays directly to the p{sub 1/2} ground state in {sup 197}Pt. The reduced E2 transition probability for this 53 keV transition has been deduced and compared with the results obtained for the corresponding transitions in other Pt, Hg, and Pb isotopes and with the theoretical predictions by Sorensen and by Wahlborn and Martinson.

  9. First 0ν half-life limit from the Gotthard xenon time projection chamber

    International Nuclear Information System (INIS)

    Wong, H.T.; Boehm, F.; Fisher, P.

    1991-01-01

    A xenon Time Projection Chamber with an active volume of 207 liters has been built to study 0ν and 2ν double beta decay in 136 Xe. The TPC has been installed in the Gotthard Tunnel Underground Laboratory, and is currently taking data with 5 atm of xenon enriched in 62.5% 136 Xe. The first 166 hours of data are presented. Based on this data set, we deduce a half-life limit of T(0 + → 0 + ) > 6.2 x 10 21 years for the 0ν mode, at a 90% C.L. (author)

  10. Precision half-life determination of a mirror β transition: The decay of 31S

    International Nuclear Information System (INIS)

    Bacquias, A.; Kurtukian-Nieto, T.; Ascher, P.; Audirac, L.; Blank, B.; Giovinazzo, J.; Aeystoe, J.; Elomaa, V.V.; Eronen, T.; Hakala, J.; Jokinen, A.; Kankainen, A.; Karvonen, P.; Kolhinen, V.S.; Moore, I.D.; Rahaman, S.; Reponen, M.; Rissanen, J.; Saastamoinen, A.; Souin, J.

    2012-01-01

    The half-life of the mirror β decay of 31 S has been measured at the IGISOL facility at the University of Jyvaeskylae. The value obtained is T 1/2 ( 31 S)=(2553.4±1.8) ms, in agreement with previous measurements, but with a precision that is better by a factor of ten than the literature value previously adopted. When the new result is combined with the Q EC value measured recently at JYFLTRAP, a precision of better than 10 -3 is obtained for the ft value. (orig.)

  11. Determination of the half-life of sup 1 sup 0 sup 5 sup m Rh

    CERN Document Server

    Kronenberg, A K; Weber, R; Esterlund, R A; Patzelt, P

    1998-01-01

    Following a fast chemical separation of Ru isotopes from a fission-product mixture, sup 1 sup 0 sup 5 sup m Rh was periodically extracted from its precursor (4.44-h sup 1 sup 0 sup 5 Ru) for measurements of its half-life. The new value for the T sub 1 sub / sub 2 of sup 1 sup 0 sup 5 sup m Rh of (43.0+-0.3) s resolves the long-standing conflict in the literature between the two earlier measured values of 45 and 30 s.

  12. Effect of change in half-life of Se-79 on the safety of HLW geological disposal system

    International Nuclear Information System (INIS)

    Ishihara, Yoshinao; Ishiguro, Katsuhiko; Umeki, Hiroyuki

    1999-11-01

    Se-79 is one of key radionuclides in the performance assessment of the geological disposal system. Based on recent measurements, it is possible that the half-life of Se-79 will be changed longer than the present value in most handbooks and tables of isotopes. This study presents performance assessment calculations to investigate the overall effect of change in half-life of Se-79 on the repository system safety. The total system performance analyses for Se-79 were carried out, which focussed on the Reference-Case of the safety assessment in the H12 Project. As results, the maximum release rate in Becquerel unit of Se-79 from the engineered barrier system with new half-life decreases about one order of magnitude than that with half-life used so far. It is, however, that the maximum release rate in Becquerel unit of Se-79 from the natural barrier system is almost same for both half-life because of the channelling effects of groundwater flow. Consequently, the calculated maximum dose rate of Se-79 with new half-life does not change. It can be concluded that the change in half-life of Se-79 does not affect overall safety of the H12 disposal concept. (author)

  13. Interjoint coordination of the lower extremities in short-track speed skating.

    Science.gov (United States)

    Khuyagbaatar, Batbayar; Purevsuren, Tserenchimed; Park, Won Man; Kim, Kyungsoo; Kim, Yoon Hyuk

    2017-10-01

    In short-track speed skating, the three-dimensional kinematics of the lower extremities during the whole skating cycle have not been studied. Kinematic parameters of the lower extremities during skating are presented as joint angles versus time. However, the angle-time presentation is not sufficient to describe the relationship between multi-joint movement patterns. Thus, angle-angle presentations were developed and used to describe interjoint coordination in sport activities. In this study, 15 professional male skaters' full body motion data were recorded using a wearable motion capture system during short-track speed skating. We investigated the three-dimensional kinematics of the lower extremities and then established the interjoint coordination between hip-knee and knee-ankle for both legs during the whole skating cycle. The results demonstrate the relationship between multi-joint movements during different phases of short-track speed skating. This study provides fundamentals of the movement mechanism of the lower extremities that can be integrated with physiotherapy to improve skating posture and prevent injuries from repetitive stress since physiological characteristics play an important role in skating performance.

  14. Isolation of human anti-serum albumin Fab antibodies with an extended serum-half life.

    Science.gov (United States)

    Kang, Hyeon-Ju; Kim, Hye-Jin; Cha, Sang-Hoon

    2016-01-01

    The serum albumin (SA) has been exploited to generate long-acting biotherapeutics by taking advantage of the FcRn-mediated recycling mechanism in a direct or an indirect way. Since Fab fragments have been proven to be clinically safe for human usage, we assumed that human anti-SA Fab antibodies could have a great potential as a carrier molecule to extend the serum half-life of therapeutic proteins. We, herein, had attempted to isolate anti-SA Fab antibodies from HuDVFab-8L antibody library via a phage display technology, and identified eight discrete human Fab antibodies. One of the Fab antibodies, SL335, showed the strongest binding reactivity to human SA with nM range of affinity at both pH 6 and pH 7.4, and cross-reacted to SAs from various species including rat, mouse, canine and monkey. The in vivo pharmacokinetic assay using a rat model indicated that SL335 has approximately 10 fold longer serum half-life and 26 to 44-fold increase in AUC0 → ∞ compared to the negative control Fab molecule in both intravenous and subcutaneous administrations. Knowing that Fabs have proven to be safe in clinics for a long time, SL335 seems to have a great potential in generating long-acting protein drugs by tagging effector molecules with either chemical conjugation or genetic fusion. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Preliminary measurements of the 87Rb half-life by means of the needle counter

    International Nuclear Information System (INIS)

    Zastawny, A.; Rabsztyn, B.

    1989-01-01

    In order to test the detector and to obtain the experience before starting the exact measurements, the measurements of 87 Rb half-life have been made. RbNO 3 produced by Merck was used to prepare the samples. The samples were prepared by evaporation of RbNO 3 water solution on an aluminium foil of 2,9 mg/cm 2 . The water solutions were changed in the range from (3286,4±1,8) x 10 -6 to (480,85±0,3) x 10 -6 . The background of the aluminium foil was equal to (0,117±0,007) cpm. In other measurements the back-scattering effect of 87 Rb beta rays on the aluminium foil amounted to 4%, as the measurements were performed in the 2π geometry. The diameters of samples were about 10 mm. The specific radioactivities of samples were measured versus the surface changed in the range (60-320) μg/cm 2 . The extrapolated value of the half-life, corrected for the chemical purity of the compound (as declared by the manufacterer) is equal to (4,86±0,1) x 10 10 years. This value is in good agreement with commonly accepted value of 4,88 x 10 10 years and with another last measurements. 10 refs., 1 fig., 2 tabs. (author)

  16. High-precision half-life measurements for the superallowed Fermi β+ emitter 14O

    Science.gov (United States)

    Laffoley, A. T.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Blank, B.; Bouzomita, H.; Cross, D. S.; Diaz Varela, A.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Giovinazzo, J.; Grinyer, G. F.; Hackman, G.; Hadinia, B.; Jamieson, D. S.; Ketelhut, S.; Leach, K. G.; Leslie, J. R.; Tardiff, E.; Thomas, J. C.; Unsworth, C.

    2013-07-01

    The half-life of the superallowed Fermi β+ emitter 14O has been determined via simultaneous direct β and γ counting experiments at TRIUMF's Isotope Separator and Accelerator (ISAC) facility. A γ-ray counting measurement was performed by detecting the 2312.6-keV γ rays emitted from an excited state of the daughter 14N following the implantation of samples at the center of the 8π γ-ray spectrometer, a spherical array of 20 high-purity germanium (HPGe) detectors. A simultaneous β counting experiment was performed using a fast plastic scintillator positioned behind the implantation site with a solid angle coverage of ˜20%. The results, T1/2(β)=70.610±0.030s and T1/2(γ)=70.632±0.094s, form a consistent set and, together with eight previous measurements, establish a new average for the 14O half-life of T1/2=70.619±0.011s with a reduced χ2 of 0.99.

  17. A new simplified allometric approach for predicting the biological half-life of radionuclides in reptiles

    International Nuclear Information System (INIS)

    Beresford, N.A.; Wood, M.D.

    2014-01-01

    A major source of uncertainty in the estimation of radiation dose to wildlife is the prediction of internal radionuclide activity concentrations. Allometric (mass-dependent) relationships describing biological half-life (T 1/2b ) of radionuclides in organisms can be used to predict organism activity concentrations. The establishment of allometric expressions requires experimental data which are often lacking. An approach to predict the T 1/2b in homeothermic vertebrates has recently been proposed. In this paper we have adapted this to be applicable to reptiles. For Cs, Ra and Sr, over a mass range of 0.02–1.5 kg, resultant predictions were generally within a factor of 6 of reported values demonstrating that the approach can be used when measured T 1/2b data are lacking. However, the effect of mass on reptilian radionuclide T 1/2b is minimal. If sufficient measured data are available for a given radionuclide then it is likely that these would give a reasonable estimate of T 1/2b in any reptile species. - Highlights: • An allometric approach to predict radionuclide T 1/2b values in reptiles is derived. • Predictions are generally within a factor of six of measured values. • Radionuclide biological half-life is in-effect mass independent

  18. Half-life data--a critical review of TECDOC-619 update

    International Nuclear Information System (INIS)

    Woods, M.J.; Collins, S.M.

    2004-01-01

    An accurate knowledge of selected nuclear decay data is critical to a wide range of processes involving radionuclides. An IAEA publication in 1991 was dedicated to the evaluation of half-lives and specific gamma-ray emission probabilities for 39 selected radionuclides considered to be important for detector efficiency calibrations. A new exercise was initiated in December 1998 to update this previous evaluation and to include a number of new radionuclides of interest; 62 radionuclides were considered along with specific parent-daughter combinations (to give a total of 64 radionuclides). That work is now being completed and a new set of recommended data is being prepared for publication. A critical comparison of the 1991 and 2003 half-life data suggests that there has not been any significant improvement in the accuracy of the recommended data. The possible reasons for this situation are discussed together with the evaluation procedure and the quality of the available data. Proposals are made for concerted actions that could lead to a significant improvement in these recommended half-life data

  19. Estimating the biological half-life for radionuclides in homoeothermic vertebrates: a simplified allometric approach

    Energy Technology Data Exchange (ETDEWEB)

    Beresford, N.A. [Lancaster Environment Centre, NERC Centre for Ecology and Hydrology, Lancaster (United Kingdom); Vives i Batlle, J. [Belgian Nuclear Research Centre, Mol (Belgium)

    2013-11-15

    The application of allometric, or mass-dependent, relationships within radioecology has increased with the evolution of models to predict the exposure of organisms other than man. Allometry presents a method of addressing the lack of empirical data on radionuclide transfer and metabolism for the many radionuclide-species combinations which may need to be considered. However, sufficient data across a range of species with different masses are required to establish allometric relationships and this is not always available. Here, an alternative allometric approach to predict the biological half-life of radionuclides in homoeothermic vertebrates which does not require such data is derived. Biological half-life values are predicted for four radionuclides and compared to available data for a range of species. All predictions were within a factor of five of the observed values when the model was parameterised appropriate to the feeding strategy of each species. This is an encouraging level of agreement given that the allometric models are intended to provide broad approximations rather than exact values. However, reasons why some radionuclides deviate from what would be anticipated from Kleiber's law need to be determined to allow a more complete exploitation of the potential of allometric extrapolation within radioecological models. (orig.)

  20. HALO--a Java framework for precise transcript half-life determination.

    Science.gov (United States)

    Friedel, Caroline C; Kaufmann, Stefanie; Dölken, Lars; Zimmer, Ralf

    2010-05-01

    Recent improvements in experimental technologies now allow measurements of de novo transcription and/or RNA decay at whole transcriptome level and determination of precise transcript half-lives. Such transcript half-lives provide important insights into the regulation of biological processes and the relative contributions of RNA decay and de novo transcription to differential gene expression. In this article, we present HALO (Half-life Organizer), the first software for the precise determination of transcript half-lives from measurements of RNA de novo transcription or decay determined with microarrays or RNA-seq. In addition, methods for quality control, filtering and normalization are supplied. HALO provides a graphical user interface, command-line tools and a well-documented Java application programming interface (API). Thus, it can be used both by biologists to determine transcript half-lives fast and reliably with the provided user interfaces as well as software developers integrating transcript half-life analysis into other gene expression profiling pipelines. Source code, executables and documentation are available at http://www.bio.ifi.lmu.de/software/halo.

  1. Peculiarities of the propagation of multidimensional extremely short optical pulses in germanene

    Energy Technology Data Exchange (ETDEWEB)

    Zhukov, Alexander V., E-mail: alex_zhukov@sutd.edu.sg [Singapore University of Technology and Design, 8 Somapah Road, 487372 Singapore (Singapore); Bouffanais, Roland [Singapore University of Technology and Design, 8 Somapah Road, 487372 Singapore (Singapore); Konobeeva, Natalia N. [Volgograd State University, 400062 Volgograd (Russian Federation); Belonenko, Mikhail B. [Laboratory of Nanotechnology, Volgograd Institute of Business, 400048 Volgograd (Russian Federation); Volgograd State University, 400062 Volgograd (Russian Federation)

    2016-09-07

    Highlights: • Established dynamics of ultra-short pulses in germanene. • Studied balance between dispersive and nonlinear effects in germanene. • Spin–orbit interaction effect onto pulse propagation. - Abstract: In this Letter, we study the propagation characteristics of both two-dimensional and three-dimensional extremely short optical pulses in germanene. A distinguishing feature of germanene—in comparison with other graphene-like structures—is the presence of a significant spin–orbit interaction. The account of this interaction has a significant impact on the evolution of extremely short pulses in such systems. Specifically, extremely short optical pulses, consisting of two electric field oscillations, cause the appearance of a tail associated with the excitation of nonlinear waves. Due to the large spin–orbit interaction in germanene, this tail behind the main pulse is much smaller in germanene-based samples as compared to graphene-based ones, thereby making germanene a preferred material for the stable propagation of pulses along the sample.

  2. High-precision half-life determination for 21Na using a 4 π gas-proportional counter

    Science.gov (United States)

    Finlay, P.; Laffoley, A. T.; Ball, G. C.; Bender, P. C.; Dunlop, M. R.; Dunlop, R.; Hackman, G.; Leslie, J. R.; MacLean, A. D.; Miller, D.; Moukaddam, M.; Olaizola, B.; Severijns, N.; Smith, J. K.; Southall, D.; Svensson, C. E.

    2017-08-01

    A high-precision half-life measurement for the superallowed β+ transition between the isospin T =1 /2 mirror nuclei 21Na and 21Ne has been performed at the TRIUMF-ISAC radioactive ion beam facility yielding T1 /2=22.4506 (33 ) s, a result that is a factor of 4 more precise than the previous world-average half-life for 21Na and represents the single most precisely determined half-life for a transition between mirror nuclei to date. The contribution to the uncertainty in the 21Na F tmirror value due to the half-life is now reduced to the level of the nuclear-structure-dependent theoretical corrections, leaving the branching ratio as the dominant experimental uncertainty.

  3. Study of the Bs meson and measurement of its half-life with the ALEPH detector

    International Nuclear Information System (INIS)

    Duarte, H.

    1994-01-01

    The B s 0 meson is the bound state of a quark anti-quark pair made up of a beauty particle and a strange particle. In the first chapter we review different experimental results leading to the existence of B S 0 meson and we draw the theoretical framework of the concept of beauty particles. The second chapter deals with the probability of the formation of a meson containing a strange quark during the fragmentation. This chapter also contains a re-analysis of the whole data constraining the mixing parameter B s 0 -B s 0 -bar. The relevancy of the analysis relies on the assumption that the B s 0 meson decays only into one D s , one lepton and one neutrino. The ALEPH detector is described in chapter 3, this four-pi, multi-particle detector is installed on the e + e - LEP (Large Electron Positron Collider). The signature selected for the measurement of the half-life is the combination of one D s in the decay modes: φπ, K *0 K with a lepton having opposite charge. This measurement implies the knowledge of the B s 0 momentum and of its flight length. In order to assess the momentum of the neutrino, a technique of measuring missing energy is presented in the chapter 4. The selection of B s 0 events is detailed in the chapter 5. A cutting limit on the energy of B s 0 based on the missing energy is used to deduce the production rate of B s 0 . In the chapter 6 we present the measurement of the half-life of B s 0 , the method used for the reconstruction of decay vertices and of the event main vertex is detailed. The validity of the method has been tested on Monte-Carlo simulations. The final result concerning the measurement of the half-life is: τ(B s )=[1.92(+0.45-0.35)±0.04] ps [fr

  4. Going Beyond the Binary : The body, Sexuality and Identity in Shelley Jackson’s Half Life: a novel

    OpenAIRE

    Liu, Linjing

    2012-01-01

    The thesis focuses on Shelley Jackson’s Half Life: a Novel with efforts directed towards a literary interpretation considering relevant issues within the context of gender and feminist theory. The argument rests upon four basic units: the theoretical framework at the outset, the question of the body next, thirdly an investigation of sexuality, and finally a consideration of identity. In Jackson’s Half Life: a Novel the non-dualist thinking underlies a deliberate play of dualism. To go beyond ...

  5. ORIGEN-S Decay Data Library and Half-Life Uncertainties

    International Nuclear Information System (INIS)

    Hermann, O.W.

    1998-01-01

    The results of an extensive update of the decay data of the ORIGEN-S library are presented in this report. The updated decay data were provided for both the ORIGEN-S and ORIGEN2 libraries in the same project. A complete edit of the decay data plus the available half-life uncertainties are included in Appendix A. A detailed description of the types of data contained in the library, the format of the library, and the data sources are also presented. Approximately 24% of the library nuclides are stable, 66% were updated from ENDF/B-VI, about 8% were updated from ENSDF, and the remaining 2% were not updated. Appendix B presents a listing of percentage changes in decay heat from the old to the updated library for all nuclides containing a difference exceeding 1% in any parameter

  6. Half-life distribution table of radioactive nuclei; Table de distribution des periodes des noyaux radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Gugenberger, P [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires

    1954-07-01

    This table allows to identify an element if its period is known. Data for this table were taken from the half-life values adopted by Hollander, PERLMAN and SEABORG (Rev. mod. Phys., 1953, 22 number 2). Moreover for each nucleus, the mass number, the charge number and the type of decay are given in the table. (author) [French] Cette table permet l'identification d'un element dont la periode est connue. Elle a ete etablie en utilisant les valeurs des periodes donnees par HOLLANDER, PERLMAN et SEABORG dans Rev. mod. Phys., 1953, 25 numero 2. On y trouve en outre, pour chaque nuclide, les caracteristiques suivantes: Z, A, modes de desintegration. (auteur)

  7. Development of CANDLES low background HPGe detector and half-life measurement of 180Tam

    Science.gov (United States)

    Chan, W. M.; Kishimoto, T.; Umehara, S.; Matsuoka, K.; Suzuki, K.; Yoshida, S.; Nakajima, K.; Iida, T.; Fushimi, K.; Nomachi, M.; Ogawa, I.; Tamagawa, Y.; Hazama, R.; Takemoto, Y.; Nakatani, N.; Takihira, Y.; Tozawa, M.; Kakubata, H.; Trang, V. T. T.; Ohata, T.; Tetsuno, K.; Maeda, T.; Khai, B. T.; Li, X. L.; Batpurev, T.

    2018-01-01

    A low background HPGe detector system was developed at CANDLES Experimental Hall for multipurpose use. Various low background techniques were employed, including hermatic shield design, radon gas suppression, and background reduction analysis. A new pulse shape discrimination (PSD) method was specially created for coaxial Ge detector. Using this PSD method, microphonics noise and background event at low energy region less than 200 keV can be rejected effectively. Monte Carlo simulation by GEANT4 was performed to acquire the detection efficiency and study the interaction of gamma-rays with detector system. For rare decay measurement, the detector was utilized to detect the nature's most stable isomer tantalum-180m (180Tam) decay. Two phases of tantalum physics run were completed with total livetime of 358.2 days, which Phase II has upgraded shield configuration. The world most stringent half-life limit of 180Tam has been successfully achieved.

  8. Half-life of each dioxin and PCB congener in the human body

    Energy Technology Data Exchange (ETDEWEB)

    Ogura, Isamura [National Institute of Advanced Industrial Science and Technology, Tsukuba (Japan)

    2004-09-15

    It is well known that dioxin and PCB congeners accumulate in the human body. For assessing their toxicological risk, it is important to know the half-life of each congener in the human body. This study summarizes the overall half-lives of congeners in humans as reported in the literature, and compares them with the half-lives due to fecal and sebum excretions, as estimated by data on the concentrations of congeners in feces and sebum in the literature. In addition, the overall half-lives of congeners for the general Japanese population were estimated from the data on dietary intakes and concentrations in the human body reported by the municipalities.

  9. The beta(+) decay and cosmic-ray half-life of Mn-54

    Science.gov (United States)

    Dacruz, M. T. F.; Norman, E. B.; Chan, Y. D.; Garcia, A.; Larimer, R. M.; Lesko, K. T.; Stokstad, R. G.; Wietfeldt, F. E.

    1993-03-01

    We performed a search for the beta(+) branch of Mn-54 decay. As a cosmic ray, Mn-54, deprived of its atomic electrons, can decay only via beta(+) and beta(-) decay, with a half-life of the order of 106 yr. This turns Mn-54 into a suitable cosmic chronometer for the study of cosmic-ray confinement times. We searched for coincident back-to-back 511-keV gamma-rays using two germanium detectors inside a Nal(Tl) annulus. An upper limit of 2 x 10-8 was found for the beta(+) decay branch, corresponding to a lower limit of 13.7 for the log ft value.

  10. Precision measurement of the half-life of $^{109}$In in large and small lattice environments

    CERN Multimedia

    We propose to undertake high precision measurements of the half-life of $^{109}$In in large and small lattice environments to study the effect of compression on the electron capture nuclear decay rate. Such studies are of general interest having implications in many areas ranging from astrophysics to geophysics. At present, very little data is available on the change of electron capture decay rate under compression and the available data seems to indicate that the observed increase of the electron capture decay rate under compression is much greater than the predictions of the best available density functional calculations as obtained from TB-LMTO or WIEN2K codes. The proposed experiment should generate more data thus clarifying the experimental situation.

  11. Half-life distribution table of radioactive nuclei; Table de distribution des periodes des noyaux radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Gugenberger, P. [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires

    1954-07-01

    This table allows to identify an element if its period is known. Data for this table were taken from the half-life values adopted by Hollander, PERLMAN and SEABORG (Rev. mod. Phys., 1953, 22 number 2). Moreover for each nucleus, the mass number, the charge number and the type of decay are given in the table. (author) [French] Cette table permet l'identification d'un element dont la periode est connue. Elle a ete etablie en utilisant les valeurs des periodes donnees par HOLLANDER, PERLMAN et SEABORG dans Rev. mod. Phys., 1953, 25 numero 2. On y trouve en outre, pour chaque nuclide, les caracteristiques suivantes: Z, A, modes de desintegration. (auteur)

  12. Development of a time-variable nuclear pulser for half life measurements

    International Nuclear Information System (INIS)

    Zahn, Guilherme S.; Domienikan, Claudio; Carvalhaes, Roberto P. M.; Genezini, Frederico A.

    2013-01-01

    In this work a time-variable pulser system with an exponentially-decaying pulse frequency is presented, which was developed using the low-cost, open-source Arduino microcontroler plataform. In this system, the microcontroller produces a TTL signal in the selected rate and a pulse shaper board adjusts it to be entered in an amplifier as a conventional pulser signal; both the decay constant and the initial pulse rate can be adjusted using a user-friendly control software, and the pulse amplitude can be adjusted using a potentiometer in the pulse shaper board. The pulser was tested using several combinations of initial pulse rate and decay constant, and the results show that the system is stable and reliable, and is suitable to be used in half-life measurements.

  13. Development of a time-variable nuclear pulser for half life measurements

    Energy Technology Data Exchange (ETDEWEB)

    Zahn, Guilherme S.; Domienikan, Claudio; Carvalhaes, Roberto P. M.; Genezini, Frederico A. [Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP. P.O. Box 11049, Sao Paulo, 05422-970 (Brazil)

    2013-05-06

    In this work a time-variable pulser system with an exponentially-decaying pulse frequency is presented, which was developed using the low-cost, open-source Arduino microcontroler plataform. In this system, the microcontroller produces a TTL signal in the selected rate and a pulse shaper board adjusts it to be entered in an amplifier as a conventional pulser signal; both the decay constant and the initial pulse rate can be adjusted using a user-friendly control software, and the pulse amplitude can be adjusted using a potentiometer in the pulse shaper board. The pulser was tested using several combinations of initial pulse rate and decay constant, and the results show that the system is stable and reliable, and is suitable to be used in half-life measurements.

  14. Biological half-life of iodine in adults with intact thyroid function and in athyreotic persons

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, G.H.; Hauck, B.M.; Chamberlain, M.J

    2002-07-01

    A joint project between the Human Monitoring Laboratory (HML) and the Ottawa Hospital has measured the retention of {sup 131}I in patients who have received the radioiodine diagnostically. Thirty-nine subjects with intact thyroid glands and nine athyreotic subjects were measured in the HML's whole-body/thyroid counter to determine the retention of {sup 131}I following its medical administration. The average biological half-life of {sup 131}I in 26 euthyroid subjects was found to be 66.1{+-}6.3 days which may be statistically significantly lower than the ICRP recommended value of 80 days. Nine hyperthyroid patients had a mean biological half-life of 38.2{+-}8.6 days and in three hypothyroid patients the corresponding value was 29.3{+-}8.8 days. Thyroid {sup 131}I uptake was measured in a conventional clinical fashion at the Ottawa Hospital Civic campus 24 h after oral administration of the radioiodine using a collimated thick sodium iodide detector placed over the neck arteriorly. Measured values were 0.144{+-}0.009, 0.314{+-}0.035 and 0.045{+-}0.010 of the administered dose in euthyroid, hyperthyroid and hypothyroid patients respectively. The euthyroid range at the hospital is 0.06-0.22. Uptake was significantly lower for the euthyroid group than the ICRP value of 0.3. The radioiodine retention in athyreotic subjects followed a two compartment model with biological half-lives of 1.0{+-}0.2 days and 18.4{+-}1.1. days. (author)

  15. Calculation of chemical elimination half-life from blood with an ongoing exposure source: the example of perfluorooctanoic acid (PFOA).

    Science.gov (United States)

    Russell, Mark H; Waterland, Robert L; Wong, Fiona

    2015-06-01

    Determination of the chemical clearance rate from human blood is a critical component of toxicokinetic exposure assessment. Analysis of temporal biomonitoring data without consideration of ongoing exposure results in calculation of apparent elimination half-life values that are longer than the intrinsic value. The intrinsic elimination half-life is solely a function of the rate of elimination while the apparent elimination half-life reflects the processes of both elimination and ongoing exposure. Confusion between intrinsic and apparent half-life values can lead to misinterpretation of biomonitoring data and can result in exaggerated predictions in subsequent modeling efforts. This work provides a review of the first-order equations that have been developed to calculate intrinsic and apparent half-life values and the potential bias that can result from confusing these two values. Published human biomonitoring data for perfluorooctanoic acid (PFOA) are analyzed using these equations to provide examples of low, medium and high bias in determination of the intrinsic elimination half-life from plasma or serum, the components of blood typically analyzed for PFOA. An approach is also provided to estimate the extent of exposure reduction that is indicated by declining longitudinal or cross-sectional biomonitoring data. Based on the evaluation methodology presented in this work, the intrinsic elimination half-life of PFOA in humans is 2.4years, representing the average of independent estimates of 2.5years (95% CI, 2.4-2.7) and 2.3years (95% CI, 2.1-2.4). The declining concentration of PFOA in blood of the general USA adult population represents an estimated exposure reduction of 20-30% over the period 1999-2008. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Pre-Clinical Intravenous Serum Pharmacokinetics of Albumin Binding and Non-Half-Life Extended Nanobodies®

    Directory of Open Access Journals (Sweden)

    Sven Hoefman

    2015-07-01

    Full Text Available Nanobodies are antigen-binding, single variable domain proteins derived from naturally-occurring, heavy chain only antibodies. They are highly soluble, stable, and can be linked to build multi-specific formats. Several Nanobodies are currently in clinical development in different therapeutic areas, for both chronic and acute applications. For the former, prolonged exposure is achieved by half-life extending moieties that target endogenous albumin, while for the latter, non-half-life extended constructs are preferable. To demonstrate the general pharmacokinetic behavior of both formats, serum levels of seven intravenously administered Nanobodies were analyzed in cynomolgus monkeys, mice or rabbits. In monkeys, the total clearance of a monomeric irrelevant Nanobody was rapid (2.0 mL/(min*kg and approximated the species glomerular filtration rate, indirectly suggesting that the Nanobody was mainly eliminated via the kidneys. When linked to an anti-albumin Nanobody, a 376-fold decrease in clearance was observed, resulting in a terminal half-life of 4.9 days, corresponding to the expected species albumin half-life. Similar conclusions were drawn for (non- half-life extended mono-, bi- and trimeric Nanobodies in mice or rabbits, suggesting that these kinetic principles apply across species. Applying this knowledge to species translation and study design is crucial for successful pre-clinical development of novel therapeutic Nanobody candidates.

  17. Extending the half-life of a fab fragment through generation of a humanized anti-human serum albumin Fv domain: An investigation into the correlation between affinity and serum half-life.

    Science.gov (United States)

    Adams, Ralph; Griffin, Laura; Compson, Joanne E; Jairaj, Mark; Baker, Terry; Ceska, Tom; West, Shauna; Zaccheo, Oliver; Davé, Emma; Lawson, Alastair Dg; Humphreys, David P; Heywood, Sam

    2016-10-01

    We generated an anti-albumin antibody, CA645, to link its Fv domain to an antigen-binding fragment (Fab), thereby extending the serum half-life of the Fab. CA645 was demonstrated to bind human, cynomolgus, and mouse serum albumin with similar affinity (1-7 nM), and to bind human serum albumin (HSA) when it is in complex with common known ligands. Importantly for half-life extension, CA645 binds HSA with similar affinity within the physiologically relevant range of pH 5.0 - pH 7.4, and does not have a deleterious effect on the binding of HSA to neonatal Fc receptor (FcRn). A crystal structure of humanized CA645 Fab in complex with HSA was solved and showed that CA645 Fab binds to domain II of HSA. Superimposition with the crystal structure of FcRn bound to HSA confirmed that CA645 does not block HSA binding to FcRn. In mice, the serum half-life of humanized CA645 Fab is 84.2 h. This is a significant extension in comparison with Fab variant. The Fab-HSA structure was used to design a series of mutants with reduced affinity to investigate the correlation between the affinity for albumin and serum half-life. Reduction in the affinity for MSA by 144-fold from 2.2 nM to 316 nM had no effect on serum half-life. Strikingly, despite a reduction in affinity to 62 µM, an extension in serum half-life of 26.4 h was still obtained. CA645 Fab and the CA645 Fab-HSA complex have been deposited in the Protein Data Bank (PDB) with accession codes, 5FUZ and 5FUO, respectively.

  18. Projected changes to short- and long-duration precipitation extremes over the Canadian Prairie Provinces

    Science.gov (United States)

    Masud, M. B.; Khaliq, M. N.; Wheater, H. S.

    2017-09-01

    The effects of climate change on April-October short- and long-duration precipitation extremes over the Canadian Prairie Provinces were evaluated using a multi-Regional Climate Model (RCM) ensemble available through the North American Regional Climate Change Assessment Program. Simulations considered include those performed with six RCMs driven by the National Centre for Environmental Prediction (NCEP) reanalysis II product for the 1981-2000 period and those driven by four Atmosphere-Ocean General Circulation Models (AOGCMs) for the current 1971-2000 and future 2041-2070 periods (i.e. a total of 11 current-to-future period simulation pairs). A regional frequency analysis approach was used to develop 2-, 5-, 10-, 25-, and 50-year return values of precipitation extremes from NCEP and AOGCM-driven current and future period simulations that respectively were used to study the performance of RCMs and projected changes for selected return values at regional, grid-cell and local scales. Performance errors due to internal dynamics and physics of RCMs studied for the 1981-2000 period reveal considerable variation in the performance of the RCMs. However, the performance errors were found to be much smaller for RCM ensemble averages than for individual RCMs. Projected changes in future climate to selected regional return values of short-duration (e.g. 15- and 30-min) precipitation extremes and for longer return periods (e.g. 50-year) were found to be mostly larger than those to the longer duration (e.g. 24- and 48-h) extremes and short return periods (e.g. 2-year). Overall, projected changes in precipitation extremes were larger for southeastern regions followed by southern and northern regions and smaller for southwestern and western regions of the study area. The changes to return values were also found to be statistically significant for the majority of the RCM-AOGCM simulation pairs. These projections might be useful as a key input for the future planning of urban

  19. Self-reflection of extremely short light pulses in nonlinear optical waveguides

    Science.gov (United States)

    Kurasov, Alexander E.; Kozlov, Sergei A.

    2004-07-01

    An equation describing the generation of reflected radiation during the propagation of high-intensity extremely short pulses in a nonlinear optical waveguide is derived. The phenomena taking place during the strong self-inducted changes of the temporal structure of the forward wave are studied. It is shown that the duration of the backward pulse is much greater than the duration of the forward pulse and that the main part of the energy of the backward wave is carried by lower frequencies than the central frequency of the forward wave.

  20. Extremely short pulses via stark modulation of the atomic transition frequencies.

    Science.gov (United States)

    Radeonychev, Y V; Polovinkin, V A; Kocharovskaya, Olga

    2010-10-29

    We propose a universal method to produce extremely short pulses of electromagnetic radiation in various spectral ranges. The essence of the method is a resonant interaction of radiation with atoms under the conditions of adiabatic periodic modulation of atomic transition frequencies by a far-off-resonant control laser field via dynamic Stark shift of the atomic levels and proper adjustment of the control field intensity and frequency, as well as the optical depth of the medium. The potential of the method is illustrated by an example in a hydrogenlike atomic system.

  1. Ecological half-life of 137Cs in plants associated with a contaminated stream

    International Nuclear Information System (INIS)

    Peles, John D.; Smith, Michael H.; Lehr Brisbin, I.

    2002-01-01

    Ecological half-life (T e ) is a useful measure for studying the long-term decline of contaminants, such as radionuclides, in natural systems. The current investigation determined levels of radiocesium ( 137 Cs) in two aquatic (Polygonum punctatum, Sagittaria latifolia) and three terrestrial (Alnus serrulata, Myrica cerifera, Salix nigra) plant species from a contaminated stream and floodplain on the U.S. Department of Energy's Savannah River Site. Current 137 Cs levels in plants were used in conjunction with historical data to determine T e of 137 Cs in each species. Median concentrations of 137 Cs were highest in S. latifolia (0.84 Bq g -1 ) and lowest in M. cerifera (0.10 Bq g -1 ). T e 's ranged from 4.85 yr in M. cerifera to 8.35 yr in S. nigra, both terrestrial species. T e 's for all aquatic (6.30 yr) and all terrestrial (5.87) species combined were very similar. The T e 's of the two aquatic primary producers (P. punctatum and S. latifolia) in the Steel Creek ecosystem were somewhat longer than T e values previously reported for some consumers from this ecosystem

  2. Prediction of thyroidal 131I effective half-life in patients with Graves' disease.

    Science.gov (United States)

    Zhang, Ruiguo; Zhang, Guizhi; Wang, Renfei; Tan, Jian; He, Yajing; Meng, Zhaowei

    2017-10-06

    Calculation of effective thyroidal half-life (Teff) of iodine-131( 131 I) is cumbersome and tedious. The aim of this study was to investigate factors that could be used to predict Teff and to develop a Teff prediction model in Graves' disease patients. A total of 256 patients with GD were involved in this study. We investigated the influences of age, gender, disease duration, thyroid weight, antithyroid drugs, antithyroid drugs discontinuation period (ADP), thyroid function indexes, thyroid autoantibodies, thyroid-stimulating hormone receptor antibody (TRAb) level and radioactive iodine uptake (RAIU) values before 131 I therapy on Teff, applying univariate and multivariate analyses. Teff correlated negatively with thyroid peroxidase antibody, TRAb and thyroid weight, as well as positively with 24-hour, 48-hour, and 72-hour RAIU. Additionally, a longer ADP (especially≥ 14d) or without antithyroid drugs before 131 I therapy led to a longer Teff. Stepwise multiple linear regression analysis showed that 24-hour and 72-hour RAIU were statistically significant predictors of Teff ( P Graves' disease, with high prediction accuracy.

  3. Kinetic modeling and half life study on bioremediation of crude oil dispersed by Corexit 9500

    International Nuclear Information System (INIS)

    Zahed, Mohammad Ali; Aziz, Hamidi Abdul; Isa, Mohamed Hasnain; Mohajeri, Leila; Mohajeri, Soraya; Kutty, Shamsul Rahman Mohamed

    2011-01-01

    Hydrocarbon pollution in marine ecosystems occurs mainly by accidental oil spills, deliberate discharge of ballast waters from oil tankers and bilge waste discharges; causing site pollution and serious adverse effects on aquatic environments as well as human health. A large number of petroleum hydrocarbons are biodegradable, thus bioremediation has become an important method for the restoration of oil polluted areas. In this research, a series of natural attenuation, crude oil (CO) and dispersed crude oil (DCO) bioremediation experiments of artificially crude oil contaminated seawater was carried out. Bacterial consortiums were identified as Acinetobacter, Alcaligenes, Bacillus, Pseudomonas and Vibrio. First order kinetics described the biodegradation of crude oil. Under abiotic conditions, oil removal was 19.9% while a maximum of 31.8% total petroleum hydrocarbons (TPH) removal was obtained in natural attenuation experiment. All DCO bioreactors demonstrated higher and faster removal than CO bioreactors. Half life times were 28, 32, 38 and 58 days for DCO and 31, 40, 50 and 75 days for CO with oil concentrations of 100, 500, 1000 and 2000 mg/L, respectively. The effectiveness of Corexit 9500 dispersant was monitored in the 45 day study; the results indicated that it improved the crude oil biodegradation rate.

  4. $\\beta$-decay half-life of $^{70}$Kr a bridge nuclide for the rp-process beyond A = 70

    CERN Document Server

    Oinonen, M; Jokinen, A; Baumann, P; Didierjean, François; Huck, A; Knipper, A; Ramdhane, M; Walter, G; Van Duppen, P; Huyse, M; Marguier, G; Novikov, Yu N; Popov, A; Seliverstov, D M; Schatz, H

    2000-01-01

    The $\\beta$-decay half-life of $^{70}$Kr has been measured for the first time at the ISOLDE PSB Facility at CERN. Mass separated $^{70}$Kr ions were produced by 1 GeV proton induced spallation reactions in a Nb foil. The measured half-life is 57(21) ms. This value is consistent with the half-life calculated assuming a pure Fermi decay, but is clearly lower than the value used in a recent rp-process reaction flow calculation. The result shows that the reaction flow via two-proton-capture of $^{68}$Se is 2.5 times faster than previously calculated assuming an astrophysical temperature of 1.5 GK and a density of 10$^{6}$g/cm$^{3}$.

  5. Towards a measurement of the half-life of {sup 60}Fe for stellar and early Solar System models

    Energy Technology Data Exchange (ETDEWEB)

    Ostdiek, K.; Anderson, T. [University of Notre Dame, Notre Dame, IN 46556 (United States); Bauder, W. [University of Notre Dame, Notre Dame, IN 46556 (United States); Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States); Bowers, M.; Collon, P. [University of Notre Dame, Notre Dame, IN 46556 (United States); Dressler, R. [Paul Scherrer Institute – Laboratory for Radiochemistry and Environmental Chemistry, 5232 Villigen (Switzerland); Greene, J. [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States); Kutschera, W. [Vienna Environmental Research Accelerator Laboratory, Waehringer Strasse 17, 1090 Vienna (Austria); Lu, W. [University of Notre Dame, Notre Dame, IN 46556 (United States); Paul, M. [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Robertson, D. [University of Notre Dame, Notre Dame, IN 46556 (United States); Schumann, D. [Paul Scherrer Institute – Laboratory for Radiochemistry and Environmental Chemistry, 5232 Villigen (Switzerland); Skulski, M. [University of Notre Dame, Notre Dame, IN 46556 (United States); Wallner, A. [The Australian National University, Canberra, ACT 0200 (Australia)

    2015-10-15

    Radioisotopes, produced in stars and ejected into the Interstellar Medium, are important for constraining stellar and early Solar System (ESS) models. In particular, the half-life of the radioisotope, {sup 60}Fe, can have an impact on calculations for the timing for ESS events, the distance to nearby Supernovae, and the brightness of individual, non-steady-state {sup 60}Fe gamma ray sources in the Galaxy. A half-life measurement has been undertaken at the University of Notre Dame and measurements of the {sup 60}Fe/{sup 56}Fe concentration of our samples using Accelerator Mass Spectrometry has begun. This result will be coupled with an activity measurement of the isomeric decay in {sup 60}Co, which is the decay product of {sup 60}Fe. Preliminary half-life estimates of (2.53 ± 0.24) × 10{sup 6} years seem to confirm the recent measurement by Rugel et al. (2009).

  6. New evaluation of alpha decay half-life of 190Pt isotope for the Pt-Os dating system

    International Nuclear Information System (INIS)

    Tavares, O.A.P.; Medeiros, E.L.; Terranova, M.L.

    2005-08-01

    A semiempirical model based on the quantum mechanical tunnelling mechanism of alpha emission from nuclei has been used to evaluate the half-life of the Pt isotopes. For the important naturally occurring 190 Pt isotope, the radiogenic parent in the 190 Pt → 186 Os dating system, the model yielded a half-life value of (3.7± 0.3) versus 10 11 y. This is comparable to (3.2±0.1) versus 10 11 y which was obtained in the last direct counting experiment to measure the alpha activity of 190 Pt (Tavares and Terranova, Rad. Measurem. 27 (1997) 19). A literature survey of available alpha decay half-life values for 190 Pt isotope is also reported. The significant discrepancies found between data obtained by direct counting, indirect geological methods and different calculation models are analysed and discussed. (author)

  7. Regional trends in short-duration precipitation extremes: a flexible multivariate monotone quantile regression approach

    Science.gov (United States)

    Cannon, Alex

    2017-04-01

    Estimating historical trends in short-duration rainfall extremes at regional and local scales is challenging due to low signal-to-noise ratios and the limited availability of homogenized observational data. In addition to being of scientific interest, trends in rainfall extremes are of practical importance, as their presence calls into question the stationarity assumptions that underpin traditional engineering and infrastructure design practice. Even with these fundamental challenges, increasingly complex questions are being asked about time series of extremes. For instance, users may not only want to know whether or not rainfall extremes have changed over time, they may also want information on the modulation of trends by large-scale climate modes or on the nonstationarity of trends (e.g., identifying hiatus periods or periods of accelerating positive trends). Efforts have thus been devoted to the development and application of more robust and powerful statistical estimators for regional and local scale trends. While a standard nonparametric method like the regional Mann-Kendall test, which tests for the presence of monotonic trends (i.e., strictly non-decreasing or non-increasing changes), makes fewer assumptions than parametric methods and pools information from stations within a region, it is not designed to visualize detected trends, include information from covariates, or answer questions about the rate of change in trends. As a remedy, monotone quantile regression (MQR) has been developed as a nonparametric alternative that can be used to estimate a common monotonic trend in extremes at multiple stations. Quantile regression makes efficient use of data by directly estimating conditional quantiles based on information from all rainfall data in a region, i.e., without having to precompute the sample quantiles. The MQR method is also flexible and can be used to visualize and analyze the nonlinearity of the detected trend. However, it is fundamentally a

  8. Examination of the biological half-life and organ d;stribution of tritiated lysin-vasopressin in Brattleboro rats

    International Nuclear Information System (INIS)

    Laczi, F.; Laszlo, F.

    1980-01-01

    15 μCi tritiated lysin-vasopressin (spec. act. 3.5 Ci per mmol) was administered to control and Brattleboro rats, suffering from hereditary hypothalamic diabetes insipidus. The biological half-life and the distribution of the labelled compound in the different organs were determined. The biological half-life demonstrated no significant difference, however, the vasopressin content of the small intestine was higher in the Brattleboro rats. In the other organs no significant difference was found. It can be concluded that the hereditary diabetes insipidus is not due to faster elimination of circulating vasopressin. (L.E.)

  9. High-Precision Half-Life Measurements for the Superallowed Fermi β+ Emitters 14O and 18Ne

    Science.gov (United States)

    Laffoley, A. T.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Bender, P. C.; Bidaman, H.; Bildstein, V.; Blank, B.; Bouzomita, H.; Cross, D. S.; Deng, G.; Diaz Varela, A.; Dunlop, M. R.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Garrett, P.; Giovinazzo, J.; Grinyer, G. F.; Grinyer, J.; Hadinia, B.; Jamieson, D. S.; Jigmeddorj, B.; Ketelhut, S.; Kisliuk, D.; Leach, K. G.; Leslie, J. R.; MacLean, A.; Miller, D.; Mills, B.; Moukaddam, M.; Radich, A. J.; Rajabali, M. M.; Rand, E. T.; Svensson, C. E.; Tardiff, E.; Thomas, J. C.; Turko, J.; Voss, P.; Unsworth, C.

    High-precision half-life measurements, at the level of ±0.04%, for the superallowed Fermi emitters 14O and 18Ne have been performed at TRIUMF's Isotope Separator and Accelerator facility. Using 3 independent detector systems, a gas-proportional counter, a fast plastic scintillator, and a high-purity germanium array, a series of direct β and γ counting measurements were performed for each of the isotopes. In the case of 14O, these measurements were made to help resolve an existing discrepancy between detection methods, whereas for 18Ne the half-life precision has been improved in anticipation of forthcoming high-precision branching ratio measurements.

  10. High-precision half-life and branching-ratio measurements for superallowed Fermi β+ emitters at TRIUMF - ISAC

    Science.gov (United States)

    Laffoley, A. T.; Dunlop, R.; Finlay, P.; Grinyer, G. F.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Blank, B.; Bouzomita, H.; Chagnon-Lessard, S.; Chester, A.; Cross, D. S.; Demand, G.; Diaz Varela, A.; Djongolov, M.; Ettenauer, S.; Garnsworthy, A. B.; Garrett, P. E.; Giovinazzo, J.; Glister, J.; Green, K. L.; Hackman, G.; Hadinia, B.; Jamieson, D. S.; Ketelhut, S.; Leach, K. G.; Leslie, J. R.; Pearson, C. J.; Phillips, A. A.; Rand, E. T.; Starosta, K.; Sumithrarachchi, C. S.; Svensson, C. E.; Tardiff, E. R.; Thomas, J. C.; Towner, I. S.; Triambak, S.; Unsworth, C.; Williams, S. J.; Wong, J.; Yates, S. W.; Zganjar, E. F.

    2014-03-01

    A program of high-precision half-life and branching-ratio measurements for superallowed Fermi β emitters is being carried out at TRIUMF's Isotope Separator and Accelerator (ISAC) radioactive ion beam facility. Recent half-life measurements for the superallowed decays of 14O, 18Ne, and 26Alm, as well as branching-ratio measurements for 26Alm and 74Rb are reported. These results provide demanding tests of the Standard Model and the theoretical isospin symmetry breaking (ISB) corrections in superallowed Fermi β decays.

  11. Examination of the biological half-life and organ d; stribution of tritiated lysin-vasopressin in Brattleboro rats

    Energy Technology Data Exchange (ETDEWEB)

    Laczi, F; Laszlo, F [Szegedi Orvostudomanyi Egyetem Szeged (Hungary). 1. Belgyogyaszati Klinika; Keri, Gy; Teplan, I [Semmelweis Orvostudomanyi Egyetem, Budapest (Hungary)

    1980-04-01

    15 ..mu..Ci tritiated lysin-vasopressin (spec. act. 3.5 Ci per mmol) was administered to control and Brattleboro rats, suffering from hereditary hypothalamic diabetes insipidus. The biological half-life and the distribution of the labelled compound in the different organs were determined. The biological half-life demonstrated no significant difference, however, the vasopressin content of the small intestine was higher in the Brattleboro rats. In the other organs no significant difference was found. It can be concluded that the hereditary diabetes insipidus is not due to faster elimination of circulating vasopressin.

  12. Real-World Analysis of Dispensed IUs of Coagulation Factor IX and Resultant Expenditures in Hemophilia B Patients Receiving Standard Half-life Versus Extended Half-life Products and Those Switching from Standard Half-life to Extended Half-life Products.

    Science.gov (United States)

    Tortella, Bartholomew J; Alvir, José; McDonald, Margaret; Spurden, Dean; Fogarty, Patrick F; Chhabra, Amit; Pleil, Andreas M

    2018-01-24

    Hemophilia B requires replacement therapy with factor IX (FIX) coagulation products to treat and prevent bleeding episodes. A recently introduced extended half-life (EHL) recombinant FIX replacement product provided the opportunity to compare the amount of dispensed factor and expenditures for EHL treatment compared with a standard half-life (SHL) product. To determine factor international units (IUs) dispensed and expenditures associated with switching from nonacog alfa, the most commonly used SHL replacement product, to eftrenonacog alfa, an EHL FIX replacement product. Two U.S. claims databases were analyzed. A large national specialty pharmacy dispensation claims database was used to identify the number of IUs dispensed and monthly charges for all patients with hemophilia B from April 2015 to June 2016. Truven Health MarketScan Research Databases (January 2010-July 2016) were used to identify IUs and expenditures for patients with claims data for at least 3 months before and after switching from the SHL to the EHL product. Medians for IUs and expenditures are presented to accommodate for skewness of data distribution. The national specialty pharmacy database analysis included 296 patients with moderate or severe hemophilia B (233 on SHL; 94 on EHL). Median monthly factor dispensed was 11% lower (2,142 IU) in the EHL versus SHL cohort over the study period, while individual monthly reductions ranged from 32% to 47% (9,838 IU to 16,514 IU). Using the wholesale acquisition cost, the median per-patient monthly factor expenditures over the 15-month study period were 94% higher ($23,005) for the EHL than for the SHL product. Individual median monthly expenditure differences ranged from 15% ($6,562) to 49% ($19,624). In the Truven database, 14 patients switched from the SHL to the EHL product. The amount of factor dispensed was variable; in the 1-year period before and after the switch from the SHL to the EHL product, mean IUs dispensed decreased by 3,005 IU, while

  13. Biological Half-Life Measurements of Radioactive Strontium in Hormonal-Resistant Prostate Cancer Patients

    International Nuclear Information System (INIS)

    Haquin, G.; Riemer, T.; Kaniun, N.; Datz, H.; Yungreiss, Z.; Vexler, A.; Ben-Yosef, R.; Pelled, O.; German, U.; Marko, R.; Teshuva, A.; Kol, R.

    2004-01-01

    Therapy for metastatic bone pain in Hormonal-Resistant Prostate Cancer (HRPC) patients is performed by administering systemic radioisotope therapy [1]. The beta radiation emitted by the radioactive strontium 89 Sr [T 1/2 =50.5 d, E β (max)=1.49 MeV], an adequate radionuclide for this therapy procedure, irradiates the metastatic cells in the bone, producing the desired palliative effect. The beta disintegration of 89 Sr is followed by a low abundance (0.00945%) gamma ray with energy of 909 keV. The commercially available 89 Sr is in the form of Sr Cl and contains an impurity of less than 0.5% of 85 Sr [T 1/2 =64.8 d] ,which decays by electron capture, emitting gamma rays at 511 keV (95.71%). The radiation dose to the metastatic cells due to the gamma rays is negligible compared to the dose given by the beta radiation, assuming that the 89 Sr is concentrated at the metastatic bony lesions. Accurate information about retention and excretion of Sr in the patient's body will contribute to better evaluate the effectiveness of the treatment. he effective half-life of 89 Sr can be calculated either from Whole Body Counting (WBC) measurements or by measuring 85 Sr and/or 89 Sr in urine/blood. WBC measurements, using collimated HPGe detectors, allow the follow-up of 89 Sr and 85 Sr at different sites in the skeletal bones of the patient. Biological half-lives of Sr in different body sections measured by WBC and the correlation with excretion-rate-based biological half-lives are presented

  14. Carboxyhemoglobin half-life during hyperbaric oxygen in a patient with lung dysfunction: a case report.

    Science.gov (United States)

    Weaver, Lindell K; Deru, Kayla

    2017-01-01

    The carboxyhemoglobin half-life (COHb t1/2) during hyperbaric oxygen (HBO₂) is often quoted as 23 minutes, derived from the average of two adult male volunteers breathing HBO₂ at 3 atmospheres absolute (ATA). However, the mean COHb t1/2 of 12 male volunteer smokers was 26.3 minutes at 1.58 ATA and in 12 non-intubated carbon monoxide (CO) poisoned patients treated at 3 ATA, was 43 minutes. An 81-year old male, poisoned by an improperly ventilated natural gas heater, was intubated for coma, then treated with HBO₂. His PaO₂/FiO₂ = 283 from aspiration. His initial COHb was 34.4%, and 18 minutes before HBO₂, 5.9%. After a compression interval of 17 minutes, the COHb measured after 22 minutes at 3 ATA was 3.3%. By exponential decay, his COHb t1/2 before HBO₂ was 95 minutes. We estimate the range for COHb t1/2 during compression as 62-81 minutes and for the 3-ATA interval, 58 to 49 minutes, respectively. The mid-point estimate of COHb t1/2 at 3 ATA was 53 minutes. The COHb t1/2 we calculated is greater than previously reported, but longer in our patient possibly because of concomitant respiratory failure, lung dysfunction, and mechanical ventilation. The often-cited COHb t1/2 of 23 minutes, likely underestimates the actual COHb t1/2 in CO-poisoned patients, especially those with cardiopulmonary dysfunction.

  15. Biological half-life of bromide in the rat depends primarily on the magnitude of sodium intake

    Czech Academy of Sciences Publication Activity Database

    Pavelka, Stanislav; Babický, Arnošt; Vobecký, Miloslav

    2005-01-01

    Roč. 54, č. 6 (2005), s. 639-644 ISSN 0862-8408 Institutional research plan: CEZ:AV0Z50110509 Keywords : biological half-life * bromide * sodium Subject RIV: ED - Physiology Impact factor: 1.806, year: 2005

  16. High-precision half-life measurements of the T =1 /2 mirror β decays 17F and 33Cl

    Science.gov (United States)

    Grinyer, J.; Grinyer, G. F.; Babo, M.; Bouzomita, H.; Chauveau, P.; Delahaye, P.; Dubois, M.; Frigot, R.; Jardin, P.; Leboucher, C.; Maunoury, L.; Seiffert, C.; Thomas, J. C.; Traykov, E.

    2015-10-01

    Background: Measurements of the f t values for T =1 /2 mirror β+ decays offer a method to test the conserved vector current hypothesis and to determine Vud, the up-down matrix element of the Cabibbo-Kobayashi-Maskawa matrix. In most mirror decays used for these tests, uncertainties in the f t values are dominated by the uncertainties in the half-lives. Purpose: Two precision half-life measurements were performed for the T =1 /2 β+ emitters, 17F and 33Cl, in order to eliminate the half-life as the leading source of uncertainty in their f t values. Method: Half-lives of 17F and 33Cl were determined using β counting of implanted radioactive ion beam samples on a moving tape transport system at the Système de Production d'Ions Radioactifs Accélérés en Ligne low-energy identification station at the Grand Accélérateur National d'Ions Lourds. Results: The 17F half-life result, 64.347 (35) s, precise to ±0.05 % , is a factor of 5 times more precise than the previous world average. The half-life of 33Cl was determined to be 2.5038 (22) s. The current precision of ±0.09 % is nearly 2 times more precise compared to the previous world average. Conclusions: The precision achieved during the present measurements implies that the half-life no longer dominates the uncertainty of the f t values for both T =1 /2 mirror decays 17F and 33Cl.

  17. Ubiquitin-fusion as a strategy to modulate protein half-life: A3G antiviral activity revisited

    International Nuclear Information System (INIS)

    Cadima-Couto, Iris; Freitas-Vieira, Acilino; Nowarski, Roni; Britan-Rosich, Elena; Kotler, Moshe; Goncalves, Joao

    2009-01-01

    The human APOBEC3G (A3G) is a potent inhibitor of HIV-1 replication and its activity is suppressed by HIV-1 virion infectivity factor (Vif). Vif neutralizes A3G mainly by inducing its degradation in the proteasome and blocking its incorporation into HIV-1 virions. Assessing the time needed for A3G incorporation into virions is, therefore, important to determine how quickly Vif must act to induce its degradation. We show that modelling the intracellular half-life of A3G can induce its Vif-independent targeting to the ubiquitin-proteasome system. By using various amino acids (X) in a cleavable ubiquitin-X-A3G fusion, we demonstrate that the half-life (t1/2) of X-A3G can be manipulated. We show that A3G molecules with a half-life of 13 min are incorporated into virions, whereas those with a half-life shorter than 5 min were not. The amount of X-A3G incorporated into virions increases from 13 min (Phe-A3G) to 85 min (Asn-A3G) and remains constant after this time period. Interestingly, despite the presence of similar levels of Arg-A3G (t1/2 = 28 min) and Asp-A3G (t1/2 = 65 min) into HIV-1 Δvif virions, inhibition of viral infectivity was only evident in the presence of A3G proteins with a longer half-life (t1/2 ≥ 65 min).

  18. Comparison of isotope dilution and excretion methods for determining the half-life of ascorbic acid in the guinea pig

    International Nuclear Information System (INIS)

    Kipp, D.E.; Rivers, J.M.

    1984-01-01

    The half-life of ascorbic acid (AA) in guinea pigs was investigated by the isotope dilution and excretion methods. The dilution method measures [1-14C]AA disappearance from the plasma, whereas the excretion method measures the elimination of [1-14C]AA and the metabolites from the body. Two groups of animals underwent both isotope studies in reverse order. Animals were conditioned to the experimental procedures and fed 2.5 mg AA/100 g body weight orally to maintain a daily intake of the vitamin independent of food consumption. The two isotope procedures imposed similar stress on the animals, as determined by plasma cortisol levels and body weight changes. The AA half-life calculations of the rapidly exchangeable pool by the isotope dilution method yielded values of 1.23 and 0.34 hours for the two groups, respectively. The half-life of the slowly exchangeable pool for the two groups was 60.2 and 65.8 hours, respectively. The half-life of AA in the rapidly exchangeable pool, as measured by the excretion studies, was 4.57-8.75 hours. For the slowly exchangeable pool, it was 146-149 hours. The longer half-life of both pools obtained with the excretion method indicates that the isotope is disappearing from the plasma more rapidly than it is being excreted. This suggests that a portion of the [1-14C]AA leaving the plasma is removed to a body pool that is not sampled by the isotope excretion method

  19. Nonlinear propagation of vector extremely short pulses in a medium of symmetric and asymmetric molecules

    Energy Technology Data Exchange (ETDEWEB)

    Sazonov, S. V., E-mail: sazonov.sergey@gmail.com [National Research Centre “Kurchatov Institute,” (Russian Federation); Ustinov, N. V., E-mail: n-ustinov@mail.ru [Moscow State University of Railways, Kaliningrad Branch (Russian Federation)

    2017-02-15

    The nonlinear propagation of extremely short electromagnetic pulses in a medium of symmetric and asymmetric molecules placed in static magnetic and electric fields is theoretically studied. Asymmetric molecules differ in that they have nonzero permanent dipole moments in stationary quantum states. A system of wave equations is derived for the ordinary and extraordinary components of pulses. It is shown that this system can be reduced in some cases to a system of coupled Ostrovsky equations and to the equation intagrable by the method for an inverse scattering transformation, including the vector version of the Ostrovsky–Vakhnenko equation. Different types of solutions of this system are considered. Only solutions representing the superposition of periodic solutions are single-valued, whereas soliton and breather solutions are multivalued.

  20. Effective Half-Life of Caesium-137 in Various Environmental Media at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M. H.; Jannik, G. T.; Baker, R. A.

    2014-05-01

    During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities into the SRS environment. However, only a relatively small number of pathways, most importantly 137Cs in fish and deer, have contributed significantly to doses and risks to the public. The “effective” half-lives (Te) of 137Cs (which include both physical decay and environmental dispersion) in Savannah River floodplain soil and vegetation and in fish and white-tailed deer from the SRS were estimated using long-term monitoring data. For 1974–2011, the Tes of 137Cs in Savannah River floodplain soil and vegetation were 17.0 years (95% CI = 14.2–19.9) and 13.4 years (95% CI = 10.8–16.0), respectively. These Tes were greater than in a previous study that used data collected only through 2005 as a likely result of changes in the flood regime of the Savannah River. Field analyses of 137Cs concentrations in deer collected during yearly controlled hunts at the SRS indicated an overall Te of 15.9 years (95% CI = 12.3–19.6) for 1965–2011; however, the Te for 1990–2011 was significantly shorter (11.8 years, 95% CI = 4.8–18.8) due to an increase in the rate of 137Cs removal. The shortest Tes were for fish in SRS streams and the Savannah River (3.5–9.0 years), where dilution and dispersal resulted in rapid 137Cs removal. Long-term data show that Tes are significantly shorter than the physical half-life of 137Cs in the SRS environment but that they can change over time. Therefore, it is desirable have a long period of record for calculating Tes and risky to extrapolate Tes beyond this period unless the processes governing 137Cs removal are clearly understood.

  1. Assessing the short-term effects of an extreme storm on Mediterranean forest raptors

    Science.gov (United States)

    Martínez, José E.; Jiménez-Franco, María V.; Zuberogoitia, Iñigo; León-Ortega, Mario; Calvo, José F.

    2013-04-01

    Different species show different responses to natural disturbances, depending on their capacity to exploit the altered environment and occupy new niches. In the case of semi-arid Mediterranean areas, there is no information available on the response of bird communities to disturbance caused by extreme weather events. Here, we evaluate the short-term effects of a heavy snowfall and strong winds on three long-lived species of forest-dwelling raptor in a semi-arid Mediterranean region situated in the south-east of Spain. The loss of nests was significantly higher in the first and second years following the disturbance than in the third year. The three species studied exhibited great tolerance to the short-term effects of the storm since we found no differences in density or reproductive parameters between the nine breeding seasons prior to the disturbance and the three which immediately followed it. We suggest that the tolerance shown by these three species to windstorms in semi-arid Mediterranean zones could be an adaptive response, resulting from the climatic and human pressures which have prevailed from the Bronze Age to the present day.

  2. Physiologically based pharmacokinetics model for estimating urinary excretion of short half-life nuclides in nuclear medicine

    International Nuclear Information System (INIS)

    Akahane, K.; Kai, M.; Konishi, E.; Kusama, T.; Aoki, Y.

    1995-01-01

    The biokinetic model in ICRP 53 is used for calculating absorbed dose to each organ of a patient in nuclear medicine. The ICRP model is a simple compartment model based on human data; however, the model cannot produce the biokinetics of radiopharmaceuticals under various physiological conditions. On the other hand, a physiologically based pharmacokinetics model (PBPK model) can describe the flow of radiopharmaceuticals as a compartment model for any physiological conditions theoretically. The PBPK model was applied especially for the kidney-bladder dynamics, and similar results obtained compared with the ICRP model. This suggests the possibility of the PBPK model for predicting the biokinetics of radiopharmaceuticals under various physiological conditions. (Author)

  3. Estimating return periods of extreme values from relatively short time series of winds

    Science.gov (United States)

    Jonasson, Kristjan; Agustsson, Halfdan; Rognvaldsson, Olafur; Arfeuille, Gilles

    2013-04-01

    An important factor for determining the prospect of individual wind farm sites is the frequency of extreme winds at hub height. Here, extreme winds are defined as the value of the highest 10 minutes averaged wind speed with a 50 year return period, i.e. annual exceeding probability of 2% (Rodrigo, 2010). A frequently applied method to estimate winds in the lowest few hundred meters above ground is to extrapolate observed 10-meter winds logarithmically to higher altitudes. Recent study by Drechsel et al. (2012) showed however that this methodology is not as accurate as interpolating simulated results from the global ECMWF numerical weather prediction (NWP) model to the desired height. Observations of persistent low level jets near Colima in SW-Mexico also show that the logarithmic approach can give highly inaccurate results for some regions (Arfeuille et al., 2012). To address these shortcomings of limited, and/or poorly representative, observations and extrapolations of winds one can use NWP models to dynamically scale down relatively coarse resolution atmospheric analysis. In the case of limited computing resources one has typically to make a compromise between spatial resolution and the duration of the simulated period, both of which can limit the quality of the wind farm siting. A common method to estimate maximum winds is to fit an extreme value distribution (e.g. Gumbel, gev or Pareto) to the maximum values of each year of available data, or the tail of these values. If data are only available for a short period, e.g. 10 or 15 years, then this will give a rather inaccurate estimate. It is possible to deal with this problem by utilizing monthly or weekly maxima, but this introduces new problems: seasonal variation, autocorrelation of neighboring values, and increased discrepancy between data and fitted distribution. We introduce a new method to estimate return periods of extreme values of winds at hub height from relatively short time series of winds, simulated

  4. Study on the biological half-life and organ-distribution of tritiated lysine-vasopressin in Brattleboro rats

    International Nuclear Information System (INIS)

    Laczi, F.; Laszlo, F.A.; Keri, Gy.; Teplan, I.

    1980-01-01

    The biological half-life and organ-distribution of tritiated lysine-vasopressin were determined in R-Amsterdam rats, and in homozygous and heterozygous Brattleboro rats with hereditary central diabetes insipidus. It was found that the biological half-life of the tritiated lysin-vasopressin in the Brattleboro rats did not differ significantly from that found in the R-Amsterdam rats. The highest radioactivities were observed in the neuro- and adenohypophyses and in the kidneys of both the R-Amsterdam and the Brattleboro rats. The accumulation of tritiated LVP was higher in the small intestine of the Brattleboro rats than in that of the R-Amsterdam animals. The results have led to the conclusion that the accelerated elimination of vasopressin and its pathologic organ-accumulation are probably not involved in the water metabolism disturbance of Brattleboro rats with hereditary hypothalamic diabetes insipidus. (author)

  5. Improved half-life determination and β-delayed γ-ray spectroscopy for 18Ne decay

    Science.gov (United States)

    Grinyer, G. F.; Ball, G. C.; Bouzomita, H.; Ettenauer, S.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Green, K. L.; Hackman, G.; Leslie, J. R.; Pearson, C. J.; Rand, E. T.; Sumithrarachchi, C. S.; Svensson, C. E.; Thomas, J. C.; Triambak, S.; Williams, S. J.

    2013-04-01

    The half-life of the superallowed Fermi β+ emitter 18Ne has been determined to ±0.07% precision by counting 1042 keV delayed γ rays that follow approximately 8% of all β decays. The deduced half-life, T1/2=1.6648(11) s, includes a 0.7% correction that accounts for systematic losses associated with rate-dependent detector pulse pileup that was determined using a recently developed γ-ray photopeak-counting technique. This result is a factor of two times more precise than, and in excellent agreement with, a previous lower-statistics measurement that employed the same experimental setup. High-resolution β-delayed γ-ray spectroscopy results for the relative γ-ray intensities and β-decay branching ratios to excited states in the daughter 18F are also presented.

  6. Measurement of the two neutrino double beta decay half-life of Zr-96 with the NEMO-3 detector

    Energy Technology Data Exchange (ETDEWEB)

    Argyriades, J. [LAL, Universite Paris-Sud 11, CNRS/IN2P3, F-91405 Orsay (France); Arnold, R. [IPHC, Universite de Strasbourg, CNRS/IN2P3, F-67037 Strasbourg (France); Augier, C. [LAL, Universite Paris-Sud 11, CNRS/IN2P3, F-91405 Orsay (France); Baker, J. [INL, Idaho National Laboratory, 83415 Idaho Falls (United States); Barabash, A.S. [ITEP, Institute of Theoretical and Experimental Physics, 117259 Moscow (Russian Federation); Basharina-Freshville, A. [University College London, WC1E 6BT London (United Kingdom); Bongrand, M. [LAL, Universite Paris-Sud 11, CNRS/IN2P3, F-91405 Orsay (France); Broudin-Bay, G. [Universite Bordeaux, CENBG, UMR 5797, F-33175 Gradignan (France); CNRS/IN2P3, Centre d' Etudes Nucleaires de Bordeaux Gradignan, UMR5797, F-33175 Gradignan (France); Brudanin, V. [JINR, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Caffrey, A.J. [INL, Idaho National Laboratory, 83415 Idaho Falls (United States); Chapon, A. [LPC, ENSICAEN, Universite de Caen, CNRS/IN2P3, F-14032 Caen (France); Chauveau, E. [Universite Bordeaux, CENBG, UMR 5797, F-33175 Gradignan (France); CNRS/IN2P3, Centre d' Etudes Nucleaires de Bordeaux Gradignan, UMR5797, F-33175 Gradignan (France); Daraktchieva, Z. [University College London, WC1E 6BT London (United Kingdom); Durand, D. [LPC, ENSICAEN, Universite de Caen, CNRS/IN2P3, F-14032 Caen (France); Egorov, V. [JINR, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Fatemi-Ghomi, N. [University of Manchester, M13 9PL Manchester (United Kingdom); Flack, R. [University College London, WC1E 6BT London (United Kingdom); Guillon, B. [LPC, ENSICAEN, Universite de Caen, CNRS/IN2P3, F-14032 Caen (France); Hubert, Ph. [Universite Bordeaux, CENBG, UMR 5797, F-33175 Gradignan (France); CNRS/IN2P3, Centre d' Etudes Nucleaires de Bordeaux Gradignan, UMR5797, F-33175 Gradignan (France); Jullian, S. [LAL, Universite Paris-Sud 11, CNRS/IN2P3, F-91405 Orsay (France)

    2010-12-08

    Using 9.4 g of {sup 96}Zr isotope and 1221 days of data from the NEMO-3 detector corresponding to 0.031 kg y, the obtained 2{nu}{beta}{beta} decay half-life measurement is T{sub 1/2}{sup 2{nu}=}[2.35{+-}0.14(stat){+-}0.16(syst)]x10{sup 19} yr. Different characteristics of the final state electrons have been studied, such as the energy sum, individual electron energy, and angular distribution. The 2{nu} nuclear matrix element is extracted using the measured 2{nu}{beta}{beta} half-life and is M{sup 2{nu}=}0.049{+-}0.002. Constraints on 0{nu}{beta}{beta} decay have also been set.

  7. Near-optimum procedure for half-life measurement by high-resolution gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Parker, J.L.

    1989-01-01

    A near-optimum procedure for using high-resolution γ-ray spectrometry to measure the half-lives of appropriate γ-ray- emitting-nuclides is presented. Among the important points of the procedure are the employment of the reference source method for implicit correction of pileup and deadtime losses; the use of full-energy peak-area ratios as the fundamental measured quantities; and continuous, high-rate data acquisition to obtain good results in a fraction of a half-life if desired. Equations are given for estimating the precision of the computed half-lives in terms of total measurement time, number of spectral acquisitions, and the precision of peak-area ratios. Results of 169 Yb half-life measurements are given as an example of the procedure's application. 3 refs., 2 tabs

  8. Use of 7Be to document soil erosion associated with a short period of extreme rainfall

    International Nuclear Information System (INIS)

    Sepulveda, A.; Schuller, P.; Walling, D.E.; Castillo, A.

    2008-01-01

    Intensification and expansion of agricultural production since the 1970s have increased soil erosion problems in south-central Chile. Quantitative information on soil loss is needed for erosion risk assessment and to establish the effectiveness of improved land management practices. Since information from traditional sources, such as erosion plots, is limited, attention has been directed to the use of environmental radionuclides for documenting erosion rates. Cs-137 has been successfully utilised for this purpose, but only provides information on medium-term erosion rates. There is also a need to document event-related soil erosion. This paper outlines the basis for using 7 Be measurements to document short-term erosion and reports its successful use for quantifying the erosion that occurred within an arable field, as a result of a period of heavy rainfall (400 mm in 27 days) occurring in May 2005. The study field had been under a no-till, no-burning system for 18 years, but immediately prior to the period of heavy rainfall the harvest residues were burnt. The erosion recorded therefore reflected both the extreme nature of the rainfall and the effects of the burning in increasing surface runoff and erosion. The sampled area corresponded to that used previously by the authors to document the medium-term erosion rates associated with both conventional tillage and the subsequent switch to a no-till system. Comparisons between the erosion documented for the period of heavy rainfall in 2005 with these medium-term erosion rates permits some tentative conclusions regarding the importance of extreme events and the impact of burning in increasing the erosion associated with the no-till system

  9. Usefulness of analytical CEA doubling time and half-life time for overlooked synchronous metastases in colorectal carcinoma.

    Science.gov (United States)

    Ito, Katsuki; Hibi, Kenji; Ando, Hideyuki; Hidemura, Kazuhiko; Yamazaki, Taiji; Akiyama, Seiji; Nakao, Akimasa

    2002-02-01

    Measurement of carcinoembryonic antigen (CEA) has been widely applied to detect recurrence, especially of colorectal carcinoma. The validity however, is still controversial. We investigated serial changes in CEA values to calculate whether the CEA doubling time and half-life time could predict metastatic progression or prognosis in colorectal carcinoma. Pre- and post-operative serial serum CEA contents were determined in 22 cases of colorectal cancer with or without metastasis. CEA values were determined by enzyme immunoassay (EIA). Patients were assigned depending upon survival time (within vs. more than 18 months after primary resection) for assessment of CEA doubling time. From the gradient of the semi-logarithmic CEA graph, the preoperative doubling time was calculated and the postoperative half-life time was estimated according to the diagnosis of metastases within 2 years after primary resection [metastasis (+) or (-)]. In spite of the effect of curative re-operation of metastatic lesions or of postoperative adjuvant chemotherapy, the CEA doubling time of the groups showed a relation with prognosis (p = 0.045, Student's t-test) when the patients were divided into >18 and time. The CEA half-life time of the groups without overlooked metastases was statistically longer than those with (mean +/- SD 8.01 +/- 2.07 and 4.33 +/- 1.11, respectively, p Clearance (k) showed a significant difference between the groups (p time appeared to be a less independent prognostic factor, whereas prolongation of the CEA half-life time might potentially suggest the existence of overlooked synchronous metastases from colorectal carcinoma.

  10. Absorption and biological half-life in humans of intrinsic and extrinsic 54Mn tracers from foods of plant origin

    International Nuclear Information System (INIS)

    Johnson, P.E.; Lykken, G.I.; Korynta, E.D.

    1991-01-01

    Absorption and biological half-life of 54 Mn were measured in adult men and women fed foods labeled intrinsically or extrinsically with 54 Mn. Each subject consumed a series of three test meals consisting of a food labeled intrinsically, a food labeled extrinsically or MnCl 2 (control) served in random order. The foods tested were lettuce, spinach, wheat and sunflower seeds. Lettuce meals and their controls contained 9.65 mumol Mn; other meals contained 22.50 mumol Mn. In addition to the test food or MnCl 2 , each meal consisted of vegetable oil (5 g), salt (NaCl, 0.15 g) and crackers (10 g), which provided 0.55 mumol Mn. There were no differences in percentage of Mn absorption or biological half-life of 54 Mn for any of the intrinsically/extrinsically labeled food pairs. Absorption of 54 Mn from MnCl 2 (8.90%) was greater than from lettuce (5.20%), spinach (3.81%), wheat (2.16%) or sunflower seeds (1.71%), but the biological half-life did not vary with the source of Mn. Absorption of 54 Mn from lettuce was significantly (P less than 0.05) greater than from wheat or sunflower seeds. Although the Mn dose in the test meal was less for lettuce than for the other foods, there was no difference in Mn absorption from MnCl 2 between the subjects fed lettuce and subjects fed other foods. There was no correlation of either 54 Mn absorption or biological half-life with whole blood or plasma Mn

  11. On the statistical evaluation of inconsistent measurement results illustrated on the example of the 90Sr half-life

    International Nuclear Information System (INIS)

    Zijp, W.L.

    1985-12-01

    The problem how to make an objective evaluation of inconsistent numerical observations made by different authors or laboratories on the same physical quantity is dealt with. The problem is treated in a practical way in the light of the example on the half-life of 90 Sr, and it is to some extent a response to a document by Gray (1985) on the same topic

  12. The Use of Gene Ontology Term and KEGG Pathway Enrichment for Analysis of Drug Half-Life.

    Directory of Open Access Journals (Sweden)

    Yu-Hang Zhang

    Full Text Available A drug's biological half-life is defined as the time required for the human body to metabolize or eliminate 50% of the initial drug dosage. Correctly measuring the half-life of a given drug is helpful for the safe and accurate usage of the drug. In this study, we investigated which gene ontology (GO terms and biological pathways were highly related to the determination of drug half-life. The investigated drugs, with known half-lives, were analyzed based on their enrichment scores for associated GO terms and KEGG pathways. These scores indicate which GO terms or KEGG pathways the drug targets. The feature selection method, minimum redundancy maximum relevance, was used to analyze these GO terms and KEGG pathways and to identify important GO terms and pathways, such as sodium-independent organic anion transmembrane transporter activity (GO:0015347, monoamine transmembrane transporter activity (GO:0008504, negative regulation of synaptic transmission (GO:0050805, neuroactive ligand-receptor interaction (hsa04080, serotonergic synapse (hsa04726, and linoleic acid metabolism (hsa00591, among others. This analysis confirmed our results and may show evidence for a new method in studying drug half-lives and building effective computational methods for the prediction of drug half-lives.

  13. Influence of antithyroid medication on effective half-life and uptake of 131 I following radioiodine therapy

    International Nuclear Information System (INIS)

    Moka, D.; Voth, E.; Schicha, H.

    1997-01-01

    Aim: A radioiodine therapy (RIT) in thyrotoxic patients receiving antithyroid drugs (ATD) leads in comparison to nonpretreated patients either to higher therapeutic doses or to higher treatment failure rates. Aim of this study was to optimize the effect of RIT in patients pretreated with ATD. Methods: Therefore, the influence of ATD was assessed in 109 patients with shortened effective half-life of 131 I. RIT was performed under stationary conditions. Radioiodine activity of the thyroid gland was stopped three days after RIT. The patients antithyroid medication was stopped three days after RIT. The progress of the first RIT and of a second radioiodine application, which still was necessary in 29 patients, was compared to 32 patients receiving ATD, continuously. Results: Values of effective half-life for 131 I rose significantly from 3.2±0.2 to 5.7±0.2 days (Graves' disease: 3.4 to 5.7 days; toxic goiters' disease: Multifocal autonomy 3.2 to 6.2 days; unifocal autonomy 2.5 auf 5.0 days) 2-3 days after stopping ATD. There was an increase of the 131 I-uptake of a second RIT decreased significantly in patients receiving ATD, continuously. Conclusion: Effective half-life and uptake of 131 I was affected significantly by ATD. The stop taking of ATD after RIT is useful to improve an apparent insufficient RIT in thyrotoxic patients receiving ATD. (orig.) [de

  14. Thirty years after Chernobyl: Long-term determination of 137Cs effective half-life in the lichen Stereocaulon vesuvianum.

    Science.gov (United States)

    Savino, F; Pugliese, M; Quarto, M; Adamo, P; Loffredo, F; De Cicco, F; Roca, V

    2017-06-01

    It has been widely shown that nuclear fallout includes substances, which accumulate in organisms such as crustaceans, fish, mushrooms and lichens, helping to evaluate the activity concentration of contaminants accumulated on a long time. In this context, radiocaesium deposited in soil following the Chernobyl accident on 26 April 1986 is known to have remained persistently available for plant uptake in many areas of Europe. Studies on the lichen Stereocaulon vesuvianum show the plant's high capacity to retain radionuclides from the substrate and the air. After the Chernobyl accident, starting from September 1986, at the Radioactivity Laboratory (LaRa) of the University of Naples Federico II, four monitoring campaigns to evaluate the activity concentration of four isotopes of the two elements caesium and ruthenium ( 134 Cs, 137 Cs, 103 Ru and 106 Ru) were carried out until 1999. This study allowed the effective half-life of 134 Cs and 137 Cs to be estimated. Twenty-eight years after the accident, in December 2014, a further sampling was carried out; only 137 Cs was revealed beyond the detection limits, measuring activity concentrations ranging from 20 to 40 Bq/kg, while the other radionuclides were no longer observed due to their shorter half-life. The last sampling allowed more precise determination of the effective half-life of 137 Cs (6.2 ± 0.1 year), due to the larger dataset on a large time period. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Extremely short relativistic-electron-bunch generation in the laser wakefield via novel bunch injection scheme

    Directory of Open Access Journals (Sweden)

    A. G. Khachatryan

    2004-12-01

    Full Text Available Recently a new electron-bunch injection scheme for the laser wakefield accelerator has been proposed [JETP Lett. 74, 371 (2001JTPLA20021-364010.1134/1.1427124; Phys. Rev. E 65, 046504 (2002PLEEE81063-651X10.1103/PhysRevE.65.046504]. In this scheme, a low energy electron bunch, sent in a plasma channel just before a high-intensity laser pulse, is trapped in the laser wakefield, considerably compressed and accelerated to an ultrarelativistic energy. In this paper we show the possibility of the generation of an extremely short (on the order of 1   μm long or a few femtoseconds in duration relativistic-electron-bunch by this mechanism. The initial electron bunch, which can be generated, for example, by a laser-driven photocathode rf gun, should have an energy of a few hundred keVs to a few MeVs, a duration in the picosecond range or less and a relatively low concentration. The trapping conditions and parameters of an accelerated bunch are investigated. The laser pulse dynamics as well as a possible experimental setup for the demonstration of the injection scheme are also considered.

  16. Extremely short light pulses: generation; diagnostics, and application in attosecond spectroscopy

    International Nuclear Information System (INIS)

    Iakovlev, V.

    2003-06-01

    The scope of the thesis includes the design of chirped mirrors, as well as theoretical investigations in the fields of high-harmonic generation and laser-dressed Auger decay, the unifying aspect being the presence of extremely short light pulses and physical processes taking place on a femtosecond scale. The main results of the research are the following: 1) It was shown that efficient global optimization of chirped mirrors is possible with an adapted version of the memetic algorithm (also known as hybrid genetic algorithm). 2) The analysis of high-harmonic spectra generated by a few-cycle laser pulse can reveal the electric field of the pulse in the vicinity of its envelope peak. The method developed for this purpose can also be regarded as a method to measure the carrier-envelope phase of laser pulses, which is more robust and has a larger range of applicability compared to the simple analysis of the cut-off region of high-harmonic spectra. 3) A quantum theory of time-resolved Auger spectroscopy was developed. Based on the essential states method, closed-form expressions for probability amplitudes were derived. The theory lays the foundation for the interpretation of experiments that probe electronic motion during atomic excitation, deexcitation, and ionization. (author)

  17. Extreme Temperature Exceedances Change more Rapidly Under Future Warming in Regions of non-Gaussian Short Temperature Distribution Tails

    Science.gov (United States)

    Loikith, P. C.; Neelin, J. D.; Meyerson, J.

    2017-12-01

    Regions of shorter-than-Gaussian warm and cold side temperature distribution tails are shown to occur in spatially coherent patterns in the current climate. Under such conditions, warming may be manifested in more complex ways than if the underlying distribution were close to Gaussian. For example, under a uniform warm shift, the simplest prototype for future warming, a location with a short warm side tail would experience a greater increase in extreme warm exceedances compared to if the distribution were Gaussian. Similarly, for a location with a short cold side tail, a uniform warm shift would result in a rapid decrease in extreme cold exceedances. Both scenarios carry major societal and environmental implications including but not limited to negative impacts on human and ecosystem health, agriculture, and the economy. It is therefore important for climate models to be able to realistically reproduce short tails in simulations of historical climate in order to boost confidence in projections of future temperature extremes. Overall, climate models contributing to the fifth phase of the Coupled Model Intercomparison Project capture many of the principal observed regions of short tails. This suggests the underlying dynamics and physics occur on scales resolved by the models, and helps build confidence in model projections of extremes. Furthermore, most GCMs show more rapid changes in exceedances of extreme temperature thresholds in regions of short tails. Results therefore suggest that the shape of the tails of the underlying temperature distribution is an indicator of how rapidly a location will experience changes to extreme temperature occurrence under future warming.

  18. Local short-duration precipitation extremes in Sweden: observations, forecasts and projections

    Science.gov (United States)

    Olsson, Jonas; Berg, Peter; Simonsson, Lennart

    2015-04-01

    Local short-duration precipitation extremes (LSPEs) are a key driver of hydrological hazards, notably in steep catchments with thin soils and in urban environments. The triggered floodings, landslides, etc., have large consequences for society in terms of both economy and health. Accurate estimations of LSPEs on both climatological time-scales (past, present, future) and in real-time is thus of great importance for improved hydrological predictions as well as design of constructions and infrastructure affected by hydrological fluxes. Analysis of LSPEs is, however, associated with various limitations and uncertainties. These are to a large degree associated with the small-scale nature of the meteorological processes behind LSPEs and the associated requirements on observation sensors as well as model descriptions. Some examples of causes for the limitations involved are given in the following. - Observations: High-resolution data sets available for LSPE analyses are often limited to either relatively long series from one or a few stations or relatively short series from larger station networks. Radar data have excellent resolutions in both time and space but the estimated local precipitation intensity is still highly uncertain. New and promising techniques (e.g. microwave links) are still in their infancy. - Weather forecasts (short-range): Although forecasts with the required spatial resolution for potential generation of LSPEs (around 2-4 km) are becoming operationally available, the actual forecast precision of LSPEs is largely unknown. Forecasted LSPEs may be displaced in time or, more critically, in space which strongly affects the possibility to assess hydrological risk. - Climate projections: The spatial resolution of the current RCM generation (around 25 km) is not sufficient for proper description of LSPEs. Statistical post-processing (i.e. downscaling) is required which adds substantial uncertainty to the final result. Ensemble generation of sufficiently

  19. On-line nuclear half life and spectroscopic measurements on mass-separated fission product nuclei

    International Nuclear Information System (INIS)

    McDonald, J.; Fogelberg, B.; Baecklin, A.

    1979-01-01

    A description is given of the methods and equipment employed for nuclear spectroscopy studies of short lived fission product nuclei at the OSIRIS ISOL facility in Studsvik, Sweden. Furthermore a table of new nuclear half-lives measured with this equipment is presented. (author)

  20. The Present Status of the Half-Life Measuring Equipment and Technique at Studsvik

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G

    1967-10-15

    The present article presents the equipment and technique used at Studsvik for measuring half-lives of nuclear excited states using the delayed coincidence method. The experimental set up includes an electron-electron coincidence spectrometer and a fast pneumatic rabbit system attached to the high flux reactor R2 at Studsvik. Special efforts have been made to adapt the system for work with short lived radioactive isotopes with decay times of the order of seconds.

  1. Evolution of extreme temperature events in short term climate projection for Iberian Peninsula.

    Science.gov (United States)

    Rodriguez, Alfredo; Tarquis, Ana M.; Sanchez, Enrique; Dosio, Alessandro; Ruiz-Ramos, Margarita

    2014-05-01

    Extreme events of maximum and minimum temperatures are a main hazard for agricultural production in Iberian Peninsula. For this purpose, in this study we analyze projections of their evolution that could be valid for the next decade, represented in this study by the 30-year period 2004-2034 (target period). For this purpose two kinds of data were used in this study: 1) observations from the station network of AEMET (Spanish National Meteorological Agency) for five Spanish locations, and 2) simulated data at a resolution of 50 ×50 km horizontal grid derived from the outputs of twelve Regional Climate Models (RCMs) taken from project ENSEMBLES (van der Linden and Mitchell, 2009), with a bias correction (Dosio and Paruolo, 2011; Dosio et al., 2012) regarding the observational dataset Spain02 (Herrera et al., 2012). To validate the simulated climate, the available period of observations was compared to a baseline period (1964-1994) of simulated climate for all locations. Then, to analyze the changes for the present/very next future, probability of extreme temperature events for 2004-2034 were compared to that of the baseline period. Although only minor changes are expected, small variations in variability may have a significant impact in crop performance. The objective of the work is to evaluate the utility of these short term projections for potential users, as for instance insurance companies. References Dosio A. and Paruolo P., 2011. Bias correction of the ENSEMBLES high-resolution climate change projections for use by impact models: Evaluation on the present climate. Journal of Geophysical Research, VOL. 116,D16106, doi:10.1029/2011JD015934 Dosio A., Paruolo P. and Rojas R., 2012. Bias correction of the ENSEMBLES high resolution climate change projections for use by impact models: Analysis of the climate change signal. Journal of Geophysical Research,Volume 117, D17, doi: 0.1029/2012JD017968 Herrera et. al. (2012) Development and Analysis of a 50 year high

  2. Phenobarbital administration every eight hours: improvement of seizure management in idiopathic epileptic dogs with decreased phenobarbital elimination half-life.

    Science.gov (United States)

    Stabile, F; Barnett, C R; De Risio, L

    2017-02-18

    Estimated prevalence of canine idiopathic epilepsy is 0.6 per cent in the first-opinion canine population in the UK. Phenobarbital monotherapy has been reported to reduce/eradicate seizure activity in 60-93 per cent of idiopathic epileptic dogs (IEDs). The objective of this study was to evaluate safety and efficacy of the administration of phenobarbital orally every eight hours in IEDs with phenobarbital elimination half-life less than 20 hours. Medical records of 10 IEDs in which steady state trough serum phenobarbital levels were within the reference range and phenobarbital elimination half-life had become less than 20 hours following prolonged administration every 12 hours were reviewed. Side effects and seizure frequency when phenobarbital was administered every 12 hours or 8 hours were compared. In all dogs the side effects of the antiepileptic medication treatment improved. When phenobarbital was administered every eight hours, 9/10 dogs experienced improvement in seizure frequency and 8/10 dogs maintained seizure freedom for a period three times longer than the longest interictal interval period previously recorded. Reduction in the severity and number of clusters of seizures was recorded in one of the remaining two dogs. The administration of phenobarbital orally every eight hours in IEDs with decreased phenobarbital elimination half-life appears safe and can improve seizure management. The results of this study were presented in abstract form (poster) for the 28th symposium of the European Society of Veterinary Neurology - European College of Veterinary Neurology (ESVN), September 18-19, 2015, Amsterdam, Netherlands. British Veterinary Association.

  3. Advances in therapeutic Fc engineering - modulation of IgG associated effector functions and serum half-life

    Directory of Open Access Journals (Sweden)

    Abhishek Saxena

    2016-12-01

    Full Text Available Today monoclonal immunoglobulin gamma (IgG antibodies have become a major option in cancer therapy especially for the patients with advanced or metastatic cancers. Efficacy of monoclonal antibodies (mAbs are achieved through both its antigen binding fragment (Fab and crystallizable fragment (Fc. Fab can specifically recognize tumor associated antigen (TAA and thus modulate TAA-linked downstream signaling pathways that may lead to inhibition of tumor growth, induction of tumor apoptosis and differentiation. The Fc region can further improve mAbs’ efficacy by mediating effector functions such as antibody-dependent cellular cytotoxicity (ADCC, complement-dependent cytotoxicity (CDC and antibody dependent cell-mediated phagocytosis (ADCP. Moreover, Fc is the region interacting with the neonatal Fc receptor (FcRn in a pH-dependent manner that can slow down IgG’s degradation and extend its serum half-life. Loss of the antibody Fc region dramatically shortens its serum half-life and weakens its anti-cancer effects. Given the essential roles that the Fc region plays in the modulation of the efficacy of mAb in cancer treatment, Fc engineering has been extensively studied in the past years. This review focuses on the recent advances in therapeutic Fc engineering that modulates its related effector functions and serum half-life. We also discuss the progress made in aglycosylated mAb development that may substantially reduce cost of manufacture but maintain similar efficacies as conventional glycosylated mAb. Finally, we highlight several Fc engineering based mAbs under clinical trials.

  4. High-precision measurement of the 19Ne half-life and implications for right-handed weak currents.

    Science.gov (United States)

    Triambak, S; Finlay, P; Sumithrarachchi, C S; Hackman, G; Ball, G C; Garrett, P E; Svensson, C E; Cross, D S; Garnsworthy, A B; Kshetri, R; Orce, J N; Pearson, M R; Tardiff, E R; Al-Falou, H; Austin, R A E; Churchman, R; Djongolov, M K; D'Entremont, R; Kierans, C; Milovanovic, L; O'Hagan, S; Reeve, S; Sjue, S K L; Williams, S J

    2012-07-27

    We report a precise determination of the (19)Ne half-life to be T(1/2)=17.262±0.007 s. This result disagrees with the most recent precision measurements and is important for placing bounds on predicted right-handed interactions that are absent in the current standard model. We are able to identify and disentangle two competing systematic effects that influence the accuracy of such measurements. Our findings prompt a reassessment of results from previous high-precision lifetime measurements that used similar equipment and methods.

  5. A Half-Life Measurement of the 343.4 keV Level in {sup 175}Lu

    Energy Technology Data Exchange (ETDEWEB)

    Hoejeberg, M; Malmskog, S G

    1969-05-15

    Great theoretical interest has recently been shown in the asymptotically forbidden 5/2 5/2+ [402] - 7/2 7/2+ [404] M1-transitions in {sup 181}Ta and {sup 175}Lu . Half-lives of the 5/2 5/2+ [402] level in {sup 175}Lu have been reported which differ by more than a factor of 10. Using an electron-electron coincidence spectrometer the half-life of this level has been re-measured and a value of (0.26 {+-} 0.02) nsec has been established.

  6. Biological half-life and distribution of radiocesium in a contaminated population of green treefrogs Hyla cinerea

    International Nuclear Information System (INIS)

    Dapson, R.W.; Kaplan, L.

    1975-01-01

    Radiocesium content of adult male green treefrogs Hyla cinerea from a contaminated habitat is adequately described by a log normal distribution with mean 2.277 log 10 pCi g -1 dry wt (189.2 pCi g -1 ) and variance of 0.031. There was significant negative correlation of body burden with body length and weight (p 2 = 0.10). Biological half-life of radiocesium in unfed, captive frogs held at 20 deg - 30 deg C averaged 30.1 d. (author)

  7. High-Precision Measurement of the Ne19 Half-Life and Implications for Right-Handed Weak Currents

    Science.gov (United States)

    Triambak, S.; Finlay, P.; Sumithrarachchi, C. S.; Hackman, G.; Ball, G. C.; Garrett, P. E.; Svensson, C. E.; Cross, D. S.; Garnsworthy, A. B.; Kshetri, R.; Orce, J. N.; Pearson, M. R.; Tardiff, E. R.; Al-Falou, H.; Austin, R. A. E.; Churchman, R.; Djongolov, M. K.; D'Entremont, R.; Kierans, C.; Milovanovic, L.; O'Hagan, S.; Reeve, S.; Sjue, S. K. L.; Williams, S. J.

    2012-07-01

    We report a precise determination of the Ne19 half-life to be T1/2=17.262±0.007s. This result disagrees with the most recent precision measurements and is important for placing bounds on predicted right-handed interactions that are absent in the current standard model. We are able to identify and disentangle two competing systematic effects that influence the accuracy of such measurements. Our findings prompt a reassessment of results from previous high-precision lifetime measurements that used similar equipment and methods.

  8. The effective and environmental half-life of 137Cs at Coral Islands at the former US nuclear test site

    International Nuclear Information System (INIS)

    Robison, William L.; Conrado, Cynthia L.; Bogen, Kenneth T.; Stoker, A. Carol

    2003-01-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 ( 137 Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of 137 Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of 137 Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of 137 Cs and 90 Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of 137 Cs and 90 Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of 137 Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the 137 Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the 137 Cs/ 90 Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the 137 Cs/ 90 Sr ratios in soil in 1987 relative to the 137 Cs/ 90 Sr ratios at the time of deposition in 1954 is less than 17 years. The magnitude of the decrease below 17 years depends on

  9. The effective and environmental half-life of 137Cs at Coral Islands at the former US nuclear test site.

    Science.gov (United States)

    Robison, William L; Conrado, Cynthia L; Bogen, Kenneth T; Stoker, A Carol

    2003-01-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 (137Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of 137Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of 137Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of 137Cs and 90Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of 137Cs and 90Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of 137Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the 137Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the 137Cs/90Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the 137Cs/90Sr ratios in soil in 1987 relative to the 137Cs/90Sr ratios at the time of deposition in 1954 is less than 17 years. The magnitude of the decrease below 17 years depends on the ELH for 90Sr

  10. The Half-Life of the HSV-1 1.5 kb LAT Intron is similar to the half-Life of the 2.0 kb LAT Intron

    Science.gov (United States)

    Brinkman, Kerry K.; Mishra, Prakhar; Fraser, Nigel W.

    2013-01-01

    Herpes Simplex Virus type 1 (HSV-1) establishes a latent infection in the sensory neurons of the peripheral nervous system of humans. Although about 80 genes are expressed during the lytic cycle of the virus infection, essentially only one gene is expressed during the latent cycle. This gene is known as the latency associated transcript (LAT) and it appears to play a role in the latency cycle through an anti-apoptotic function in the 5’ end of the gene and miRNA encoded along the length of the transcript which down regulate some of the viral immediate early (IE) gene products. The LAT gene is about 8.3 kb long and consists of two exons separated by an unusual intron. The intron between the exons consists of two nested introns. This arrangement of introns has been called a twintron. Furthermore, the larger (2 kb) intron has been shown to be very stable. In this study we measure the stability of the shorter 1.5 kb nested intron and find its half-life is similar to the longer intron. This was achieved by deleting the 0.5 kb overlapping intron from a plasmid construct designed to express the LAT transcript from a tet-inducible promoter, and measuring the half-life of the 1.5 kb intron in tissue culture cells. This finding supports the hypothesis that it is the common branch-point region of these nested introns that is responsible for their stability. PMID:23335177

  11. Fab-dsFv: A bispecific antibody format with extended serum half-life through albumin binding.

    Science.gov (United States)

    Davé, Emma; Adams, Ralph; Zaccheo, Oliver; Carrington, Bruce; Compson, Joanne E; Dugdale, Sarah; Airey, Michael; Malcolm, Sarah; Hailu, Hanna; Wild, Gavin; Turner, Alison; Heads, James; Sarkar, Kaushik; Ventom, Andrew; Marshall, Diane; Jairaj, Mark; Kopotsha, Tim; Christodoulou, Louis; Zamacona, Miren; Lawson, Alastair D; Heywood, Sam; Humphreys, David P

    2016-10-01

    An antibody format, termed Fab-dsFv, has been designed for clinical indications that require monovalent target binding in the absence of direct Fc receptor (FcR) binding while retaining substantial serum presence. The variable fragment (Fv) domain of a humanized albumin-binding antibody was fused to the C-termini of Fab constant domains, such that the VL and VH domains were individually connected to the Cκ and CH1 domains by peptide linkers, respectively. The anti-albumin Fv was selected for properties thought to be desirable to ensure a durable serum half-life mediated via FcRn. The Fv domain was further stabilized by an inter-domain disulfide bond. The bispecific format was shown to be thermodynamically and biophysically stable, and retained good affinity and efficacy to both antigens simultaneously. In in vivo studies, the serum half-life of Fab-dsFv, 2.6 d in mice and 7.9 d in cynomolgus monkeys, was equivalent to Fab'-PEG.

  12. Ultra-High Precision Half-Life Measurement for the Superallowed &+circ; Emitter ^26Al^m

    Science.gov (United States)

    Finlay, P.; Demand, G.; Garrett, P. E.; Leach, K. G.; Phillips, A. A.; Sumithrarachchi, C. S.; Svensson, C. E.; Triambak, S.; Grinyer, G. F.; Leslie, J. R.; Andreoiu, C.; Cross, D.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Djongolov, M.; Ettenauer, S.; Hackman, G.; Pearson, C. J.; Williams, S. J.

    2009-10-01

    The calculated nuclear structure dependent correction for ^26Al^m (δC-δNS= 0.305(27)% [1]) is smaller by nearly a factor of two than the other twelve precision superallowed cases, making it an ideal case to pursue a reduction in the experimental errors contributing to the Ft value. An ultra-high precision half-life measurement for the superallowed &+circ; emitter ^26Al^m has been made at the Isotope Separator and Accelerator (ISAC) facility at TRIUMF in Vancouver, Canada. A beam of ˜10^5 ^26Al^m/s was delivered in October 2007 and its decay was observed using a 4π continuous gas flow proportional counter as part of an ongoing experimental program in superallowed Fermi β decay studies. With a statistical precision of ˜0.008%, the present work represents the single most precise measurement of any superallowed half-life to date. [4pt] [1] I.S. Towner and J.C. Hardy, Phys. Rev. C 79, 055502 (2009).

  13. High-Precision Half-Life and Branching Ratio Measurements for the Superallowed β+ Emitter 26Alm

    Science.gov (United States)

    Finlay, P.; Svensson, C. E.; Demand, G. A.; Garrett, P. E.; Green, K. L.; Leach, K. G.; Phillips, A. A.; Rand, E. T.; Ball, G.; Bandyopadhyay, D.; Djongolov, M.; Ettenauer, S.; Hackman, G.; Pearson, C. J.; Leslie, J. R.; Andreoiu, C.; Cross, D.; Austin, R. A. E.; Grinyer, G. F.; Sumithrarachchi, C. S.; Williams, S. J.; Triambak, S.

    2013-03-01

    High-precision half-life and branching-ratio measurements for the superallowed β+ emitter 26Alm were performed at the TRIUMF-ISAC radioactive ion beam facility. An upper limit of ≤ 15 ppm at 90% C.L. was determined for the sum of all possible non-analogue β+/EC decay branches of 26Alm, yielding a superallowed branching ratio of 100.0000+0-0.0015%. A value of T1/2 = 6:34654(76) s was determined for the 26Alm half-life which is consistent with, but 2.5 times more precise than, the previous world average. Combining these results with world-average measurements yields an ft value of 3037.58(60) s, the most precisely determined for any superallowed emitting nucleus to date. This high-precision ft value for 26Alm provides a new benchmark to refine theoretical models of isospin-symmetry-breaking effects in superallowed β decays.

  14. RBC-/Cr-51/ half-life and albumin turnover in growing Beagle dogs during chronic radial acceleration

    Science.gov (United States)

    Beckman, D. A.; Evans, J. W.; Oyama, J.

    1979-01-01

    The effects of chronic centrifugation on growing Beagle dogs exposed to -2 or -2.6 Gx on albumin and RBC turnover rates, albumin concentration and space, and total blood volume were determined and compared with caged and run control of animals. Albumin-(I-125) and autologous RBC-(Cr-51) preparations were injected into all dogs at day 82 of the centrifugation periods, and the disappearance curves were determined by successive bleedings of the animals over the next 35 d, during which the centrifugation was continued. There were no differences in albumin turnover rates or space. Two populations of RBCs were found in both centrifugated groups, one with a normal half-life of 27 + or - 1 S.E.M. d, and one with a significantly (p less than 0.01) shorter half-life of 15 + or - 2 S.E.M. d. An absolute polycythemia was also observed in both centrifuged groups. The results suggest that chronic centrifugation acts through some as-yet unknown mechanism to affect RBC population kinetics.

  15. Medical and psychosocial implications of adolescent extreme obesity – acceptance and effects of structured care, short: Youth with Extreme Obesity Study (YES)

    Science.gov (United States)

    2013-01-01

    Background Prevalence rates of overweight and obesity have increased in German children and adolescents in the last three decades. Adolescents with extreme obesity represent a distinct risk group. On the basis of data obtained by the German Child and Youth Survey (KiGGS) and the German district military offices we estimate that the group of extremely obese adolescents (BMI ≥ 35 kg/m2) currently encompasses approximately 200.000 adolescents aged 14 to 21 yrs. Conventional approaches focusing on weight reduction have largely proven futile for them. In addition, only a small percentage of adolescents with extreme obesity seek actively treatment for obesity while contributing disproportionately strong to health care costs. Because of somatic and psychiatric co-morbidities and social problems adolescents with extreme obesity require special attention within the medical care system. We have initiated the project “Medical and psychosocial implications of adolescents with extreme obesity - acceptance and effects of structured care, short: ‘Youths with Extreme Obesity Study (YES)’”, which aims at improving the medical care and social support structures for youths with extreme obesity in Germany. Methods/Design We focus on identification of these subjects (baseline examination) and their acceptance of diagnostic and subsequent treatment procedures. In a randomized controlled trial (RCT) we will investigate the effectiveness of a low key group intervention not focusing on weight loss but aimed at the provision of obesity related information, alleviation of social isolation, school and vocational integration and improvement of self-esteem in comparison to a control group treated in a conventional way with focus on weight loss. Interested individuals who fulfill current recommended criteria for weight loss surgery will be provided with a structured preparation and follow-up programs. All subjects will be monitored within a long-term observational study to

  16. Medical and psychosocial implications of adolescent extreme obesity - acceptance and effects of structured care, short: Youth with Extreme Obesity Study (YES).

    Science.gov (United States)

    Wabitsch, Martin; Moss, Anja; Reinehr, Thomas; Wiegand, Susanna; Kiess, Wieland; Scherag, André; Holl, Reinhard; Holle, Rolf; Hebebrand, Johannes

    2013-08-29

    Prevalence rates of overweight and obesity have increased in German children and adolescents in the last three decades. Adolescents with extreme obesity represent a distinct risk group. On the basis of data obtained by the German Child and Youth Survey (KiGGS) and the German district military offices we estimate that the group of extremely obese adolescents (BMI ≥ 35 kg/m2) currently encompasses approximately 200.000 adolescents aged 14 to 21 yrs. Conventional approaches focusing on weight reduction have largely proven futile for them. In addition, only a small percentage of adolescents with extreme obesity seek actively treatment for obesity while contributing disproportionately strong to health care costs. Because of somatic and psychiatric co-morbidities and social problems adolescents with extreme obesity require special attention within the medical care system. We have initiated the project "Medical and psychosocial implications of adolescents with extreme obesity--acceptance and effects of structured care, short: 'Youths with Extreme Obesity Study (YES)'", which aims at improving the medical care and social support structures for youths with extreme obesity in Germany. We focus on identification of these subjects (baseline examination) and their acceptance of diagnostic and subsequent treatment procedures. In a randomized controlled trial (RCT) we will investigate the effectiveness of a low key group intervention not focusing on weight loss but aimed at the provision of obesity related information, alleviation of social isolation, school and vocational integration and improvement of self-esteem in comparison to a control group treated in a conventional way with focus on weight loss. Interested individuals who fulfill current recommended criteria for weight loss surgery will be provided with a structured preparation and follow-up programs. All subjects will be monitored within a long-term observational study to elucidate medical and psychosocial outcomes

  17. Relationship between isotope half-life and prostatic edema for optimal prostate dose coverage in permanent seed implants

    International Nuclear Information System (INIS)

    Villeneuve, Maxime; Leclerc, Ghyslain; Lessard, Etienne; Pouliot, Jean; Beaulieu, Luc

    2008-01-01

    The robustness of treatment planning to prostatic edema for three different isotopes ( 125 I, 103 Pd, and 131 Cs) is explored using dynamical dose calculations on 25 different clinical prostate cases. The treatment plans were made using the inverse planning by simulated annealing (IPSA) algorithm. The prescription was 144, 127, and 125 Gy for 125 I, 131 Cs, and 103 Pd, respectively. For each isotope, three dose distribution schemes were used to impose different protection levels to the urethra: V 120 =0%, V 150 =0%, and V 150 =30%. Eleven initial edema values were considered ranging from 1.0 (no edema) to 2.0 (100%). The edema was assumed to resolve exponentially with time. The prostate volume, seed positions, and seed activity were dynamically tracked to produce the final dose distribution. Edema decay half-lives of 10, 30, and 50 days were used. A total of 675 dynamical calculations were performed for each initial edema value. For the 125 I isotope, limiting the urethra V 120 to 0% leads to a prostate D 90 under 140 Gy for initial edema values above 1.5. Planning with urethra V 150 at 0% provides a good response to the edema; the prostate D 90 remains higher than 140 Gy for edema values up to 1.8 and a half-life of 30 days or less. For 103 Pd, the prostate D 90 is under 97% of the prescription dose for approximately 66%, 40%, and 30% of edema values for urethra V 120 =0%, V 150 =0%, and V 150 =30%, respectively. Similar behavior is seen for 131 Cs and the center of the prostate becomes 'cold' for almost all edema scenarios. The magnitude of the edema following prostate brachytherapy, as well as the half-life of the isotope used and that of the edema resorption, all have important impacts on the dose distribution. The 125 I isotope with its longer half-life is more robust to prostatic edema. Setting up good planning objectives can provide an adequate compromise between organ doses and robustness. This is even more important since seed misplacements will contribute

  18. Direct Deposition Effect on the Distribution of Radiocesium in Persimmon Trees and the Effective Half-life

    Energy Technology Data Exchange (ETDEWEB)

    Tagami, Keiko; Uchida, Shigeo [National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-7444 (Japan)

    2014-07-01

    Radiocesium ({sup 137}Cs) concentrations in persimmon tree tissues collected at Chiba, about 220 km south from Fukushima Daiichi nuclear power plant (FDNPP), were measured to obtain half-life of radiocesium in the trees. Persimmon (Diospyros kaki) is a deciduous tree and bears edible fruits in autumn. There were no leaves when the sampling area was received the radioactive fallout in March 2011 due to the FDNPP accident; the amount of {sup 137}Cs radioactivity in this area was ca. 13 kBq/m{sup 3} Both {sup 137}Cs and {sup 134}Cs were found in the newly emerged shoots of the persimmon trees collected at 26 April 2011 mainly due to foliar uptake. The concentrations were 1.1 kBq/kg-dry for {sup 137}Cs and 1.3 kBq/kg-dry for {sup 134}Cs. After that, continuous sampling of leaves, branches and fruits of the persimmon trees had been carried out for two years. Immediately after the collection, samples were transferred to our laboratory and weighed to obtain fresh weight. Leaf samples were usually separated into two portions; one portion was washed with tap water to remove dust from the surface and the other portion was not treated. For fruit samples, if it is possible, fruit flesh, peal and non-edible part were separated. All the samples were oven-dried at 80 deg. C for three days at least. Each dried sample was chopped into fine pieces, mixed well, and then transferred into plastic vessels separately. Radioactivity concentration was measured by a Ge-detecting system (Seiko EG and G Ortec) using 3000-40000 s counting intervals. By August 14, 2013, about 140 samples were collected from the trees; about 60 samples were leaves (both washed and untreated). Radiocesium concentrations in tree leaves decreased with time, and the effective half-life was about 190 d; the value was similar to those in branches (160 d for new branches, and 250 d for 1-2 y.o. branches) and fruits (250 d for fruit flesh and 230 d for peals). Thus we concluded that the half-life of radiocesium in

  19. Energy dependence of average half-life of delayed neutron precursors in fast neutron induced fission of 235U and 236U

    International Nuclear Information System (INIS)

    Isaev, S.G.; Piksaikin, L.E.; Kazakov, L.E.; Tarasko, M.Z.

    2000-01-01

    The measurements of relative abundances and periods of delayed neutrons from fast neutron induced fission of 235 U and 236 U have been made at the electrostatic accelerator CG-2.5 at IPPE. The preliminary results were obtained and discussed in the frame of the systematics of the average half-life of delayed neutron precursors. It was shown that the average half-life value in both reactions depends on the energy of primary neutrons [ru

  20. Tests of the methods of analysis of picosecond lifetimes and measurement of the half-life of the 569.6 keV level in 207Pb

    International Nuclear Information System (INIS)

    Lima, E. de; Kawakami, H.; Lima, A. de; Hichwa, R.; Ramayya, A.V.; Hamilton, J.H.; Dunn, W.; Kim, H.J.

    1978-01-01

    Customarily one extracts the half-life of the nuclear state from a delayed time spectrum by an analysis of the centroid shift, the slope and lately by the convolution method. Recently there have been two formulas relating the centroid shift to the half-life of the nuclear state. These two procedures can give different results for the half-life when Tsub(1/2) the same order or less than the time width of one channel. An extensive investigation of these two formulas and precedures has been made by measuring the half-life of the first excited state in 207 Pb at 569.6 keV. This analysis confirms Bay's formula relating the centroid shift to the half-life of the state. The half-life of the 569.6 keV level in 207 Pb is measured to be (129+-3) ps in excellent agreement with Weisskopf's single particle estimate of 128 ps for an E2 transition. (Auth.)

  1. Phenytoin shortens the half-life of the hypoxic cell radiosensitizer misonidazole in man: implications for possible reduced toxicity

    International Nuclear Information System (INIS)

    Workman, P.; Bleehen, N.M.; Wiltshire, C.R.; Cambridge Univ.

    1980-01-01

    Results are described of a preliminary study of the effects of phenytoin, (commonly used as an anticonvulsant in the treatment of patients with brain tumours), on the plasma pharmacokinetics of misonidazole (MISO) in man. Previous studies have shown that pretreatment with phenytoin shortens the half-life of MISO in dogs and mice by induction of drug metabolizing enzymes, and also reduces the acute lethal effects of MISO in mice. In this study patients with various types of malignancy and with cerebral metastases were given MISO before and after a course of phenytoin. Others were assessed as controls without phenytoin administration. Plasma concentrations of MISO were determined in blood samples taken before and at various times after administration. A summary of the pharmacokinetic data obtained is given. (author)

  2. KINETIC MODELLING AND HALF LIFE STUDY OF ADSORPTIVE BIOREMEDIATION OF SOIL ARTIFICIALLY CONTAMINATED WITH BONNY LIGHT CRUDE OIL

    Directory of Open Access Journals (Sweden)

    Samuel Enahoro Agarry

    2015-06-01

    Full Text Available In this study, comparative potential effects of commercial activated carbon (CAC and plantain peel-derived biochar (PPBC of different particle sizes and dosage to stimulate petroleum hydrocarbon biodegradation in soil were investigated. Microcosms containing soil were spiked with weathered Bonny light crude oil (WBLCO (10% w/w and amended with different particle sizes (0.02, 0.07 and 0.48 mm and dosage (20, 30 and 40 g of CAC and PPBC, respectively. The bioremediation experiments were carried out for a period of 28 days under laboratory conditions. The results showed that there was a positive relationship between the rate of petroleum hydrocarbons reduction and presence of the CAC and PPBC in crude oil contaminated soil microcosms. The WBLCO biodegradation data fitted well to the first-order kinetic model. The model revealed that WBLCO contaminated-soil microcosms amended with CAC and PPBC had higher biodegradation rate constants (k as well as lower half-life times (t1/2 than unamended soil (natural attenuation remediation system. The rate constants increased while half-life times decreased with decreased particle size and increased dosage of amendment agents. ANOVA statistical analysis revealed that WBLCO biodegradation in soil was significantly (p = 0.05 influenced by the addition of CAC and biochar amendment agents, respectively. However, Tukey’s post hoc test (at p = 0.05 showed that there was no significant difference in the bioremediation efficiency of CAC and PPBC. Thus, amendment of soils with biochar has the potential to be an inexpensive, efficient, environmentally friendly and relatively novel strategy to mitigate organic compound-contaminated soil.

  3. A Hybrid Short-Term Traffic Flow Prediction Model Based on Singular Spectrum Analysis and Kernel Extreme Learning Machine.

    Directory of Open Access Journals (Sweden)

    Qiang Shang

    Full Text Available Short-term traffic flow prediction is one of the most important issues in the field of intelligent transport system (ITS. Because of the uncertainty and nonlinearity, short-term traffic flow prediction is a challenging task. In order to improve the accuracy of short-time traffic flow prediction, a hybrid model (SSA-KELM is proposed based on singular spectrum analysis (SSA and kernel extreme learning machine (KELM. SSA is used to filter out the noise of traffic flow time series. Then, the filtered traffic flow data is used to train KELM model, the optimal input form of the proposed model is determined by phase space reconstruction, and parameters of the model are optimized by gravitational search algorithm (GSA. Finally, case validation is carried out using the measured data of an expressway in Xiamen, China. And the SSA-KELM model is compared with several well-known prediction models, including support vector machine, extreme learning machine, and single KLEM model. The experimental results demonstrate that performance of the proposed model is superior to that of the comparison models. Apart from accuracy improvement, the proposed model is more robust.

  4. Risk models for lower extremity injuries among short- and long distance runners : A prospective cohort study

    NARCIS (Netherlands)

    van Poppel, Dennis; Scholten-Peeters, Gwendolijne G.M.; van Middelkoop, Marienke; Koes, Bart W.; Verhagen, Arianne P.

    2018-01-01

    Background: Running injuries are very common. Risk factors for running injuries are not consistently described across studies and do not differentiate between runners of long- and short distances within one cohort. Objectives: The aim of this study is to determine risk factors for running injuries

  5. Label-free Fab and Fc affinity/avidity profiling of the antibody complex half-life for polyclonal and monoclonal efficacy screening.

    Science.gov (United States)

    Read, Thomas; Olkhov, Rouslan V; Williamson, E Diane; Shaw, Andrew M

    2015-09-01

    A unified approach to affinity screening for Fab and Fc interactions of an antibody for its antigen and FcγR receptor has been developed. An antigen array is used for the Fab affinity and cross-reactivity screening and protein A/G proxy is the FcγR receptor. The affinities are derived using a simple 1:1 binding model with a consistent error analysis. The association and dissociation kinetics are measured over optimised times for accurate determination. The Fab/Fc affinities are derived for ten antibodies: mAb-actin (mouse), pAb-BSA (sheep), pAb-collagen V (rabbit), pAb-CRP (goat), mAb-F1 (mouse), mAbs (mouse) 7.3, 12.3, 29.3, 36.3 and 46.3 raised against LcrV in Yersinia pestis. The rate of the dissociation of antigen-antibody complexes relates directly to their immunological function as does the Fc-FcγR complex and a new half-life plot has been defined with a Fab/Fc half-life range of 17-470 min. The upper half-life value points to surface avidity. Two antibodies that are protective as an immunotherapy define a Fab half-life >250 min and an Fc half-life >50 min as characteristics of ideal interactions which can form the basis of an antibody screen for immunotherapy.

  6. HPLC Analysis to Determine the Half-life and Bioavailability of the Termiticides Bifenthrin and Fipronil in Soil.

    Science.gov (United States)

    Manzoor, F; Pervez, M

    2017-12-05

    The aim of this study was to test the bioavailability and degradation in soil of the termiticides bifenthrin and fipronil, which are used to treat subterranean termites (Heterotermes indicola, Wasmann). Soil collected from different areas of Lahore was categorized as sandy clay loam (SCL) or sandy loam (SL). Laboratory bioassays were conducted to determine the bioavailability ratio of bifenthrin and fipronil in each type of soil after different periods of time. LT50 values were determined posttreatment at different time intervals. Regarding soil type, both termiticides were more effective in SL soil, compared with SCL soil posttreatment. There were significant differences in termite mortality in treated compared with untreated control samples (P bifenthrin (maximum, 1,002 and 1,262 d in SCL soil and SL soil, respectively) indicated that it persisted in both soil types at all concentrations. The maximum calculated half-life values of fipronil were 270 and 555 d in SCL and SL soil, respectively. At lower concentrations and over longer periods of time, fipronil completely degraded in SL soil, while a negligible amount was detected in SCL soil. Termiticide concentration decreased over time, as did the termiticide recovery rate. Overall, bifenthrin was more persistent than fipronil under all treatment conditions tested. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Degradation and half-life of DNA present in biomass from a genetically-modified organism during land application.

    Science.gov (United States)

    Halter, Mathew C; Zahn, James A

    2017-02-01

    White biotechnology has made a positive impact on the chemical industry by providing safer, more efficient chemical manufacturing processes that have reduced the use of toxic chemicals, harsh reaction conditions, and expensive metal catalysts, which has improved alignment with the principles of Green Chemistry. The genetically-modified (GM) biocatalysts that are utilized in these processes are typically separated from high-value products and then recycled, or eliminated. Elimination routes include disposal in sanitary landfills, incineration, use as a fuel, animal feed, or reuse as an agricultural soil amendment or other value-added products. Elimination routes that have the potential to impact the food chain or environment have been more heavily scrutinized for the fate and persistence of biological products. In this study, we developed and optimized a method for monitoring the degradation of strain-specific DNA markers from a genetically-modified organism (GMO) used for the commercial production of 1,3-propanediol. Laboratory and field tests showed that a marker for heterologous DNA in the GM organism was no longer detectable by end-point polymerase chain reaction (PCR) after 14 days. The half-life of heterologous DNA was increased by 17% (from 42.4 to 49.7 h) after sterilization of the soil from a field plot, which indicated that abiotic factors were important in degradation of DNA under field conditions. There was no evidence for horizontal transfer of DNA target sequences from the GMO to viable organisms present in the soil.

  8. Dependence of Rn adsorption rate and effective half-life time on diffusion barrier type and moving air environment

    International Nuclear Information System (INIS)

    Arafa, Wafaa; Badran, Heba

    2005-01-01

    The variation of the adsorbed radon rate during the exposure time using charcoal canister was studied applying moving air environment inside the radon chamber and compared to the static air measurements. The air movement increases the accumulation time leading to more accurate results. Different types of membrane have been tested as diffusion barrier for activated charcoal canisters. The Makrofol and aluminized polycarbonate improve the adsorption/desorption rate more than the polyehylene membrane. The measured effective half-life time showed a remarkable correlation with the previously measured permeability constant for corresponding membranes. Different types of commercially available charcoal were investigated to develop a local version of charcoal canister for radon measurements. Applying static and moving air environments, the break point and radon collection efficiency were determined at different temperatures. Both of the temperature and air movement accelerate the appearance of the break point. Th efficiency of the locally developed charcoal is 87% and 84.5% of that Calgon PCB charcoal used by EPA. (author)

  9. Increased half-life and enhanced potency of Fc-modified human PCSK9 monoclonal antibodies in primates.

    Directory of Open Access Journals (Sweden)

    Yijun Shen

    Full Text Available Blocking proprotein convertase subtilisin kexin type 9 (PCSK9 binding to low-density lipoprotein receptor (LDLR can profoundly lower plasma LDL levels. Two anti-PCKS9 monoclonal antibodies (mAbs, alirocumab and evolocumab, were approved by the FDA in 2015. The recommended dose is 75 mg to 150 mg every two weeks for alirocumab and 140mg every two weeks or 420 mg once a month for evolocumab. This study attempted to improve the pharmacokinetic properties of F0016A, an IgG1 anti-PCKS9 mAb, to generate biologically superior molecules. We engineered several variants with two or three amino acid substitutions in the Fc fragment based on prior knowledge. The Fc-modified mAbs exhibited increased binding to FcRn, resulting in prolonged serum half-life and enhanced efficacy in vivo. These results demonstrate that Fc-modified anti-PCKS9 antibodies may enable less frequent or lower dosing of antibodies by improved recycling into the blood.

  10. Diffusion and release of noble gas and halogen fission products with several days half-life in UO2 particle

    International Nuclear Information System (INIS)

    Fang Chao

    2013-01-01

    The exact solutions of diffusion and release model of noble gas and halogen fission products in UO 2 particle of HTGR were built under the conditions of adsorption effect and other physical processes. The corresponding release fractions (F(t)) and the ratio of release and productive amounts (R(t)/B (t)) of fission products were also derived. Furthermore, the F(t) and R(t)/B(t) of 131 I, 131 IXe m , 133 Xe and 133 Xe m whose half-lifes are several days in UO 2 particle with the exact solutions, approximate solutions and corresponding numerical solutions under different temperature histories of reactor core were investigated. The results show that the F(t) and R(t)/B(t) are different in numerical values unless the time of release is long enough. The properties of conservation of exact solutions are much more reasonable than the ones of approximate solutions. It is also found that the results of exact solutions approach the actual working conditions more than the approximate and numerical solutions. (author)

  11. Developments in human growth hormone preparations: sustained-release, prolonged half-life, novel injection devices, and alternative delivery routes

    Directory of Open Access Journals (Sweden)

    Cai Y

    2014-07-01

    Full Text Available Yunpeng Cai,1,2 Mingxin Xu,2 Minglu Yuan,2 Zhenguo Liu,1 Weien Yuan2 1Department of Neurology, Xinhua Hospital, School of Medicine, 2School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People’s Republic of China Abstract: Since the availability of recombinant human growth hormone (rhGH enabled the application of human growth hormone both in clinical and research use in the 1980s, millions of patients were prescribed a daily injection of rhGH, but noncompliance rates were high. To address the problem of noncompliance, numerous studies have been carried out, involving: sustained-release preparations, prolonged half-life derivatives, new injectors that cause less pain, and other noninvasive delivery methods such as intranasal, pulmonary and transdermal deliveries. Some accomplishments have been made and launched already, such as the Nutropin Depot® microsphere and injectors (Zomajet®, Serojet®, and NordiFlex®. Here, we provide a review of the different technologies and illustrate the key points of these studies to achieve an improved rhGH product. Keywords: intranasal, pulmonary, transdermal, microsphere, microneedle, hydrogel

  12. Extremely short duration high intensity interval training substantially improves insulin action in young healthy males

    DEFF Research Database (Denmark)

    Babraj, John A; Vollaard, Niels B J; Keast, Cameron

    2009-01-01

    BACKGROUND: Traditional high volume aerobic exercise training reduces cardiovascular and metabolic disease risk but involves a substantial time commitment. Extremely low volume high-intensity interval training (HIT) has recently been demonstrated to produce improvements to aerobic function...... cycle sprints per session). Aerobic performance (250-kJ self-paced cycling time trial), and glucose, insulin and NEFA responses to a 75-g oral glucose load (oral glucose tolerance test; OGTT) were determined before and after training. RESULTS: Following 2 weeks of HIT, the area under the plasma glucose......, to substantially improve insulin action in young sedentary subjects is remarkable. This novel time-efficient training paradigm can be used as a strategy to reduce metabolic risk factors in young and middle aged sedentary populations who otherwise would not adhere to time consuming traditional aerobic exercise...

  13. Thermotolerance and Photosystem II Behaviour in Co-occuring Temperate Tree Species Exposed to Short-term Extreme Heat Waves

    Science.gov (United States)

    Guha, A.; Warren, J.; Cummings, C.; Han, J.

    2017-12-01

    Thermal stress can induce irreversible photodamage with longer consequences for plant metabolism. We focused on photosystem II (PSII) behaviour to understand how this complex responds in different co-occuring temperate trees exposed to short-term extreme heat waves. The study was designed for understanding complex heat tolerance mechanisms in trees. During manipulative heat-wave experiments, we monitored instantaneous PSII performance and tracked both transient and chronic PSII damages using chlorophyll a fluorescence characteristics. Fluorescence signals were used to simulate PSII bioenergetic processes. The light (Fv'/Fm') and dark-adapted (Fv/Fm) fluorescence traits including fast induction kinetics (OJIP), electron transport rate, PSII operating efficiency and quenching capacities were significantly affected by the heat treatments. Loss in PSII efficiency was more apparent in species like black cottonwood, yellow poplar, walnuts and conifers, whereas oaks maintained relatively better PSII functions. The post-heat recovery of Fv/Fm varied across the studied species showing differential carry over effects. PSII down-regulation was one of dominant factors for the loss in operational photosynthesis during extreme heat wave events. Both light and dark-adapted fluorescence characteristics showed loss in photo-regulatory functions and photodamage. Some resilient species showed rapid recovery from transient PSII damage, whereas fingerprints of chronic PSII damage were observed in susceptibles. Thresholds for Fv/Fm and non-photochemical quenching were identified for the studied species. PSII malfunctioning was largely associated with the observed photosynthetic down-regulation during heat wave treatments, however, its physiological recovery should be a key factor to determine species resilience to short-term extreme heat wave events.

  14. Half-life, branching-ratio, and Q-value measurement for the superallowed 0+→0+β+ emitter 42Ti

    International Nuclear Information System (INIS)

    Nieto, T. Kurtukian; Souin, J.; Audirac, L.; Blank, B.; Giovinazzo, J.; Eronen, T.; Aeystoe, J.; Elomaa, V.-V.; Hager, U.; Hakala, J.; Jokinen, A.; Kankainen, A.; Karvonen, P.; Kessler, T.; Moore, I. D.; Penttilae, H.; Rahaman, S.; Reponen, M.; Rissanen, J.; Saastamoinen, A.

    2009-01-01

    The half-life, the branching ratio, and the decay Q value of the superallowed β emitter 42 Ti were measured in an experiment performed at the JYFLTRAP facility of the Accelerator Laboratory of the University of Jyvaeskylae. 42 Ti is the heaviest T z =-1 nucleus for which high-precision measurements of these quantities have been tried. The half-life (T 1/2 =208.14±0.45 ms) and the Q value [Q EC =7016.83(25) keV] are close to or reach the required precision of about 0.1%. The branching ratio for the superallowed decay branch [BR=47.7(12)%], a by-product of the half-life measurement, does not reach the necessary precision yet. Nonetheless, these results allow one to determine the experimental ft value and the corrected Ft value to be 3114(79) and 3122(79) s, respectively.

  15. Analysis of existing data and specification of an experiment to determine the 252Cf half-life to the required degree of accuracy

    International Nuclear Information System (INIS)

    Lorenz, A.; Kharitonov, I.A.

    1994-02-01

    The methods used and the results obtained in measurements of the 252 Cf half-life are analyzed. In calculating the weighted mean value, additional error components as well as those given by the authors are taken into account. In order to reduce the error in the weighted mean value to less than 0.1%, the need and the requirements for an exact measurement are specified. A half-life of 2.6473±0.0028 years is recommended. (author). 16 refs, 3 tabs

  16. High-precision half-life measurements of the T=1/2 mirror beta decays F-17 and Cl-33

    OpenAIRE

    Grinyer, J; Grinyer, G. F; Babo, Mathieu; Bouzomita, H; Chauveau, P; Delahaye, P; Dubois, M; Frigot, R; Jardin, P; Leboucher, C; Maunoury, L; Seiffert, C; Thomas, J. C; Traykov, E

    2015-01-01

    Background: Measurements of the ft values for T=1/2 mirror β+ decays offer a method to test the conserved vector current hypothesis and to determine Vud, the up-down matrix element of the Cabibbo-Kobayashi-Maskawa matrix. In most mirror decays used for these tests, uncertainties in the ft values are dominated by the uncertainties in the half-lives. Purpose: Two precision half-life measurements were performed for the T=1/2β+ emitters, 17F and 33Cl, in order to eliminate the half-life as th...

  17. High-precision half-life measurements of the T=1/2 mirror β decays F17 and Cl33

    OpenAIRE

    Grinyer, J; Grinyer, G F; Babo, M; Bouzomita, H; Chauveau, P; Delahaye, P; Dubois, M; Frigot, R; Jardin, P; Leboucher, C; Maunoury, L; Seiffert, C; Thomas, J C; Traykov, E

    2015-01-01

    Background: Measurements of the ft values for T=1/2 mirror β+ decays offer a method to test the conserved vector current hypothesis and to determine Vud, the up-down matrix element of the Cabibbo-Kobayashi-Maskawa matrix. In most mirror decays used for these tests, uncertainties in the ft values are dominated by the uncertainties in the half-lives. Purpose: Two precision half-life measurements were performed for the T=1/2β+ emitters, F17 and Cl33, in order to eliminate the half-life as the le...

  18. A Two-pronged Binding Mechanism of IgG to the Neonatal Fc Receptor Controls Complex Stability and IgG Serum Half-life

    DEFF Research Database (Denmark)

    Jensen, Pernille Foged; Schoch, Angela; Larraillet, Vincent

    2017-01-01

    The success of recombinant monoclonal immunoglobulins (IgG) is rooted in their ability to target distinct antigens with high affinity combined with an extraordinarily long serum half-life, typically around 3 weeks. The pharmacokinetics of IgGs is intimately linked to the recycling mechanism...... half-life of ∼8 days. Here we dissect the molecular origins of excessive FcRn binding in therapeutic IgGs using a combination of hydrogen/deuterium exchange mass spectrometry and FcRn affinity chromatography. We provide experimental evidence for a two-pronged IgG-FcRn binding mechanism involving direct...

  19. Short-term cropland responses to temperature extreme events during late winter

    Science.gov (United States)

    De Simon, G.; Alberti, G.; Delle Vedove, G.; Peressotti, A.; Zaldei, A.; Miglietta, F.

    2013-08-01

    In recent years, several studies have focused on terrestrial ecosystem response to extreme events. Most of this research has been conducted in natural ecosystems, but few have considered agroecosystems. In this study, we investigated the impact of a manipulated warmer or cooler late winter/early spring on the carbon budget and final harvest of a soybean crop (Glycine max (L.) Merr.). Soil temperature was altered by manipulating soil albedo by covering the soil surface with a layer of inert silica gravel. We tested three treatments - cooling (Co), warming (W), mix (M) - and control (C). An automated system continuously measured soil heterotrophic respiration (Rh), soil temperature profiles, and soil water content across the entire year in each plot. Phenological phases were periodically assessed and final harvest was measured in each plot. Results showed that treatments had only a transient effect on daily Rh rates, which did not result in a total annual carbon budget significantly different from control, even though cooling showed a significant reduction in final harvest. We also observed anticipation in emergence in both W and M treatments and a delay in emergence for Co. Moreover, plant density and growth increased in W and M and decreased in Co. In conclusion, from the results of our experiment we can assert that an increase in the frequency of both heat and cold waves is unlikely to have large effects on the overall annual carbon balance of irrigated croplands.

  20. Some models of propagation of extremely short electromagnetic pulses in a nonlinear medium

    International Nuclear Information System (INIS)

    Maimistov, Andrei I

    2000-01-01

    Some cases of model media considered in this paper allow analytical solutions to nonlinear wave equations to be found and the time dependence of the electric field strength to be determined in the explicit form for arbitrarily short electromagnetic pulses. Our analysis does not employ any assumptions concerning a harmonic carrier wave or the variation rate of the field in such pulses. The class of models considered includes two-level resonance and quasi-resonance systems. Nonresonance media are analysed in terms of models of anharmonic oscillators - the Duffing and Lorentz models. In most cases, only particular solutions describing the stationary propagation of a video pulse (a unipolar transient of the electric field or a pulse including a small number of oscillations of the electric field around zero) can be found. These solutions correspond to sufficiently strong electromagnetic fields when the dispersion inherent in the medium is suppressed by nonlinear processes. (invited paper)

  1. Phenological response of an Arizona dryland forest to short-term climatic extremes

    Science.gov (United States)

    Walker, Jessica; de Beurs, Kirsten; Wynne, Randolph

    2015-01-01

    Baseline information about dryland forest phenology is necessary to accurately anticipate future ecosystem shifts. The overarching goal of our study was to investigate the variability of vegetation phenology across a dryland forest landscape in response to climate alterations. We analyzed the influence of site characteristics and climatic conditions on the phenological patterns of an Arizona, USA, ponderosa pine (Pinus ponderosa) forest during a five-year period (2005 to 2009) that encompassed extreme wet and dry precipitation regimes. We assembled 80 synthetic Landsat images by applying the spatial and temporal adaptive reflectance fusion method (STARFM) to 500 m MODIS and 30 m Landsat-5 Thematic Mapper (TM) data. We tested relationships between site characteristics and the timing of peak Normalized Difference Vegetation Index (NDVI) to assess the effect of climatic stress on the green-up of individual pixels during or after the summer monsoon. Our results show that drought-induced stress led to a fragmented phenological response that was highly dependent on microsite parameters, as both the spatial autocorrelation of peak timing and the number of significant site variables increased during the drought year. Pixels at lower elevations and with higher proportions of herbaceous vegetation were more likely to exhibit dynamic responses to changes in precipitation conditions. Our study demonstrates the complexity of responses within dryland forest ecosystems and highlights the need for standardized monitoring of phenology trends in these areas. The spatial and temporal variability of phenological signals may provide a quantitative solution to the problem of how to evaluate dryland land surface trends across time.

  2. Phenological Response of an Arizona Dryland Forest to Short-Term Climatic Extremes

    Directory of Open Access Journals (Sweden)

    Jessica Walker

    2015-08-01

    Full Text Available Baseline information about dryland forest phenology is necessary to accurately anticipate future ecosystem shifts. The overarching goal of our study was to investigate the variability of vegetation phenology across a dryland forest landscape in response to climate alterations. We analyzed the influence of site characteristics and climatic conditions on the phenological patterns of an Arizona, USA, ponderosa pine (Pinus ponderosa forest during a five-year period (2005 to 2009 that encompassed extreme wet and dry precipitation regimes. We assembled 80 synthetic Landsat images by applying the spatial and temporal adaptive reflectance fusion method (STARFM to 500 m MODIS and 30 m Landsat-5 Thematic Mapper (TM data. We tested relationships between site characteristics and the timing of peak Normalized Difference Vegetation Index (NDVI to assess the effect of climatic stress on the green-up of individual pixels during or after the summer monsoon. Our results show that drought-induced stress led to a fragmented phenological response that was highly dependent on microsite parameters, as both the spatial autocorrelation of peak timing and the number of significant site variables increased during the drought year. Pixels at lower elevations and with higher proportions of herbaceous vegetation were more likely to exhibit dynamic responses to changes in precipitation conditions. Our study demonstrates the complexity of responses within dryland forest ecosystems and highlights the need for standardized monitoring of phenology trends in these areas. The spatial and temporal variability of phenological signals may provide a quantitative solution to the problem of how to evaluate dryland land surface trends across time.

  3. Ceramide binding to anandamide increases its half-life and potentiates its cytotoxicity in human neuroblastoma cells.

    Science.gov (United States)

    Di Scala, Coralie; Mazzarino, Morgane; Yahi, Nouara; Varini, Karine; Garmy, Nicolas; Fantini, Jacques; Chahinian, Henri

    2017-06-01

    Anandamide (AEA) is a ubiquitous lipid that exerts neurotransmitter functions but also controls important biological functions such as proliferation, survival, or programmed cell death. The latter effects are also regulated by ceramide, a lipid enzymatically generated from sphingomyelin hydrolysis by sphingomyelinase. Ceramide has been shown to increase the cellular toxicity of AEA, but the mechanisms controlling this potentiating effect remained unclear. Here we have used a panel of in silico, physicochemical, biochemical and cellular approaches to study the crosstalk between AEA and ceramide apoptotic pathways. Molecular dynamics simulations indicated that AEA and ceramide could form a stable complex in phosphatidylcholine membranes. Consistent with these data, we showed that AEA can specifically insert into ceramide monolayers whereas it did not penetrate into sphingomyelin membranes. Then we have studied the effects of ceramide on AEA-induced toxicity of human neuroblastoma cells. In these experiments, the cells have been either naturally enriched in ceramide by neutral sphingomyelinase pre-incubation or treated with C2-ceramide, a biologically active ceramide analog. Both treatments significantly increased the cytotoxicity of AEA as assessed by the MTS mitochondrial toxicity assay. This effect was correlated with the concomitant accumulation of natural ceramide (or its synthetic analog) and AEA in the cells. A kinetic study of AEA hydrolysis showed that ceramide inhibited the fatty acid amino hydrolase (FAAH) activity in cell extracts. Taken together, these data suggested that ceramide binds to AEA, increases its half-life and potentiates its cytotoxicity. Overall, these mechanisms account for a functional cross-talk between AEA and ceramide apoptotic pathways. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Measurement of the half-life of 60Fe using the Argonne FN tandem-superconducting Linac system as an accelerator mass spectrometer

    International Nuclear Information System (INIS)

    Kutschera, W.; Billquist, P.J.; Frekers, D.

    1983-01-01

    An experiment to improve the accuracy in the half-life value of 60 Fe by measuring both the amount of 60 Fe nuclei and the decay-rate of a spallation produced sample using the relation dN/dt = -lambda N is briefly discussed

  5. New limit on the half-life of 78Kr with respect to the 2K(2ν)-capture decay mode

    International Nuclear Information System (INIS)

    Gavriljuk, Ju.M.; Kuzminov, V.V.; Osetrova, N.Ya.; Ratkevich, S.S.

    2000-01-01

    The features of data accumulated for 1817 h in an experimental search for the 2K(2ν)-capture mode of 78 Kr decay are discussed. A new limit on the half-life for this decay is found: T 1sol2 ≥ 2.3 x 10 20 yr (at a 90% C.L.)

  6. Platelet half-life in patients with primary hyperlipoproteinemia type IIa, IIb, and IV according to Fredrickson with and without clinical signs of atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, E; Sinzinger, H; Widhalm, K; Kaliman, J; Hoefer, R [Vienna Univ. (Austria). 2. Medizinische Klinik; Ludwig Boltzmann-Institut fuer Nuklearmedizin, Vienna (Austria); Vienna Univ. (Austria). Kinderklinik; Vienna Univ. (Austria). Kardiologische Klinik)

    1982-09-01

    It is generally accepted that platelet half-life is shortened in atherosclerotic vascular diseases. Concerning changes due to hyperlipoproteinemia (HLP), however, there exist only few data. Therefore, we examined the platelet-half life in 60 patients with recently discovered HLP type IIa, IIb and IV according to Fredrickson before treatment in comparison to 60 controls. 33 of the HLP-patients had no clinical symptoms of angiopathy. 27 patients suffered from peripheral vascular disease or from coronary heart disease as verified by angiography. The labelling of autologous platelets was performed with 100..mu..Ci of /sup 111/Indium-oxine-sulfate at 37/sup 0/C for 5 minutes. The mean labelling efficiency was 90%, the recovery after 2 hours about 70%. Serum lipoproteins were estimated by means of ultracentrifugation and polyanionprecipitation according to Lipid Research Clinic Methods. In the patients with HLP platelet half-life was significantly shortened in comparison to the control group (p < 0.01). These changes were most pronounced in patients with HLP-type IIa and with atherosclerotic lesions, respectively. In patients with HLP-type IIa a very close correlation could be demonstrated between platelet half-life and LDL-cholesterol (r = -0.72; p < 0.001) as well as total cholesterol (r = -0.73; p < 0.001). These data prove that in HLP in-vivo platelet function as measured by platelet survival is significantly influenced even before the occurrence of clinically relevant symptoms of atherosclerosis.

  7. A new value for the half-life of {sup 10}Be by Heavy-Ion Elastic Recoil Detection and liquid scintillation counting

    Energy Technology Data Exchange (ETDEWEB)

    Korschinek, G., E-mail: Gunther.Korschinek@ph.tum.d [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Bergmaier, A. [Universitaet der Bundeswehr Muenchen, Fakultaet fuer Luft- und Raumfahrttechnik, Institut fuer Angewandte Physik und Messtechnik LRT2, Werner-Heisenberg-Weg 39, D-85577 Neubiberg (Germany); Faestermann, T. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Gerstmann, U.C. [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstaedter Landstr. 1, D-85764 Neuherberg (Germany); Knie, K.; Rugel, G. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Wallner, A. [VERA Laboratory, Faculty of Physics, University of Vienna, Waehringer Strasse 17, A-1090 Wien (Austria); Dillmann, I. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Dollinger, G. [Universitaet der Bundeswehr Muenchen, Fakultaet fuer Luft- und Raumfahrttechnik, Institut fuer Angewandte Physik und Messtechnik LRT2, Werner-Heisenberg-Weg 39, D-85577 Neubiberg (Germany); Lierse von Gostomski, Ch. [Lehrstuhl fuer Radiochemie, Technische Universitaet Muenchen, D-85748 Garching (Germany); Kossert, K. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Maiti, M.; Poutivtsev, M. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Remmert, A. [Lehrstuhl fuer Radiochemie, Technische Universitaet Muenchen, D-85748 Garching (Germany)

    2010-01-15

    The importance of {sup 10}Be in different applications of accelerator mass spectrometry (AMS) is well-known. In this context the half-life of {sup 10}Be has a crucial impact, and an accurate and precise determination of the half-life is a prerequisite for many of the applications of {sup 10}Be in cosmic-ray and earth science research. Recently, the value of the {sup 10}Be half-life has been the centre of much debate. In order to overcome uncertainties inherent in previous determinations, we introduced a new method of high accuracy and precision. An aliquot of our highly enriched {sup 10}Be master solution was serially diluted with increasing well-known masses of {sup 9}Be. We then determined the initial {sup 10}Be concentration by least square fit to the series of measurements of the resultant {sup 10}Be/{sup 9}Be ratio. In order to minimize uncertainties because of mass bias which plague other low-energy mass spectrometric methods, we used for the first time Heavy-Ion Elastic Recoil Detection (HI-ERD) for the determination of the {sup 10}Be/{sup 9}Be isotopic ratios, a technique which does not suffer from difficult to control mass fractionation. The specific activity of the master solution was measured by means of accurate liquid scintillation counting (LSC). The resultant combination of the {sup 10}Be concentration and activity yields a {sup 10}Be half-life of T{sub 1/2} = 1.388 +- 0.018 (1 s, 1.30%) Ma. In a parallel but independent study (Chmeleff et al. ), found a value of 1.386 +- 0.016 (1.15%) Ma. Our recommended weighted mean and mean standard error for the new value for {sup 10}Be half-life based on these two independent measurements is 1.387 +- 0.012 (0.87%) Ma.

  8. Effective Half-life of I-131 in Patients with Differentiated Thyroid Cancer Treated by Radioactive I-131

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seok Gun [Dankook University, Cheonan (Korea, Republic of)

    2008-12-15

    Effective half life of I-131 (T{sub eff}) in patients with differentiated thyroid cancer treated by I-131 is must-know value for dose calculation and determination of release time from isolation room. There has been no report about T{sub eff} in Koreans. Thus, author tried to measure dose rate without radiation exposure to faculty members and calculated T{sub eff}. Probe of radiation survey meter was fixed at the wall of isolation room, and body of survey meter was placed outside the room. With this simple arrangement, author could measure radiation frequently without radiation exposure to faculty members in 68 patient (F=55, M=13, age=47{+-}13.7) treated by I-131 (3.7{approx}7.4 GBq) for differentiated thyroid cancer from Jan 2006 to Dec 2006. From this data, T{sub eff}, 48 hr retention rate, and the time necessary to whole body retention of I-131 become less than 1.1 GBq were calculated. Serum creatinine levels were measured before and after thyroid hormone withdrawal. T{sub eff} was 15.4{+-}4.3 hr (9.4{approx}32.5 hr). There was a loose correlation between T{sub eff} and serum creatinine concentration (r=0.45). 48hr retention was 4.9{+-}4.2% (1{approx}23%). Time necessary to whole body retention of I-131 become less than 1.1 GBq was calculated as 47.1{+-}13.2 hr for 9.25 GBq, 42.1{+-}11.9 hr for 7.4 GBq, 35.7{+-}10.0 hr for 5.55 GBq, and 26.7{+-}7.5 hr for 3.7 GBq dose of I-131. Author successfully measured radiation dose rates in isolated patients treated by high dose of I-131 without radiation exposure to the faculty members with simple arrangement of survey meter probe. Using those data, T{sub eff} and some other indices were calculated.

  9. Determining thyroid {sup 131}I effective half-life for the treatment planning of Graves' disease

    Energy Technology Data Exchange (ETDEWEB)

    Willegaignon, Jose; Sapienza, Marcelo T.; Barberio Coura Filho, George; Buchpiguel, Carlos A. [Cancer Institute of Sao Paulo State (ICESP), Clinical Hospital, School of Medicine, University of Sao Paulo, Sao Paulo 01246-000 (Brazil); Nuclear Medicine Service, Department of Radiology, School of Medicine, University of Sao Paulo, Sao Paulo 01246-000 (Brazil); Traino, Antonio C. [Unit of Medical Physics, Azienda Ospedaliero-Universitaria Pisana, Pisa 56126 (Italy)

    2013-02-15

    Purpose: Thyroid {sup 131}I effective half-life (T{sub eff}) is an essential parameter in patient therapy when accurate radiation dose is desirable for producing an intended therapeutic outcome. Multiple {sup 131}I uptake measurements and resources from patients themselves and from nuclear medicine facilities are requisites for determining T{sub eff}, these being limiting factors when implementing the treatment planning of Graves' disease (GD) in radionuclide therapy. With the aim of optimizing this process, this study presents a practical, propitious, and accurate method of determining T{sub eff} for dosimetric purposes. Methods: A total of 50 patients with GD were included in this prospective study. Thyroidal {sup 131}I uptake was measured at 2-h, 6-h, 24-h, 48-h, 96-h, and 220-h postradioiodine administration. T{sub eff} was calculated by considering sets of two measured points (24-48-h, 24-96-h, and 24-220-h), sets of three (24-48-96-h, 24-48-220-h, and 24-96-220-h), and sets of four (24-48-96-220-h). Results: When considering all the measured points, the representative T{sub eff} for all the patients was 6.95 ({+-}0.81) days, whereas when using such sets of points as (24-220-h), (24-96-220-h), and (24-48-220-h), this was 6.85 ({+-}0.81), 6.90 ({+-}0.81), and 6.95 ({+-}0.81) days, respectively. According to the mean deviations 2.2 ({+-}2.4)%, 2.1 ({+-}2.0)%, and 0.04 ({+-}0.09)% found in T{sub eff}, calculated based on all the measured points in time, and with methods using the (24-220-h), (24-48-220-h), and (24-96-220-h) sets, respectively, no meaningful statistical difference was noted among the three methods (p > 0.500, t test). Conclusions: T{sub eff} obtained from only two thyroid {sup 131}I uptakes measured at 24-h and 220-h, besides proving to be sufficient, accurate enough, and easily applicable, attributes additional major cost-benefits for patients, and facilitates the application of the method for dosimetric purposes in the treatment planning of

  10. Role of short-term dispersal on the dynamics of Zika virus in an extreme idealized environment

    Directory of Open Access Journals (Sweden)

    Victor M. Moreno

    2017-02-01

    Full Text Available In November 2015, El Salvador reported their first case of Zika virus (ZIKV infection, an event followed by an explosive outbreak that generated over 6000 suspected cases in a period of two months. National agencies began implementing control measures that included vector control and recommending an increased use of repellents. Further, in response to the alarming and growing number of microcephaly cases in Brazil, the importance of avoiding pregnancies for two years was stressed. In this paper, we explore the role of mobility within communities characterized by extreme poverty, crime and violence. Specifically, the role of short term mobility between two idealized interconnected highly distinct communities is explored in the context of ZIKV outbreaks. We make use of a Lagrangian modeling approach within a two-patch setting in order to highlight the possible effects that short-term mobility, within highly distinct environments, may have on the dynamics of ZIKV outbreak when the overall goal is to reduce the number of cases not just in the most affluent areas but everywhere. Outcomes depend on existing mobility patterns, levels of disease risk, and the ability of federal or state public health services to invest in resource limited areas, particularly in those where violence is systemic. The results of simulations in highly polarized and simplified scenarios are used to assess the role of mobility. It quickly became evident that matching observed patterns of ZIKV outbreaks could not be captured without incorporating increasing levels of heterogeneity. The number of distinct patches and variations on patch connectivity structure required to match ZIKV patterns could not be met within the highly aggregated model that is used in the simulations. Keywords: Vector-borne diseases, Zika virus, Residence times, Multi-patch model

  11. Short-Term Electricity-Load Forecasting Using a TSK-Based Extreme Learning Machine with Knowledge Representation

    Directory of Open Access Journals (Sweden)

    Chan-Uk Yeom

    2017-10-01

    Full Text Available This paper discusses short-term electricity-load forecasting using an extreme learning machine (ELM with automatic knowledge representation from a given input-output data set. For this purpose, we use a Takagi-Sugeno-Kang (TSK-based ELM to develop a systematic approach to generating if-then rules, while the conventional ELM operates without knowledge information. The TSK-ELM design includes a two-phase development. First, we generate an initial random-partition matrix and estimate cluster centers for random clustering. The obtained cluster centers are used to determine the premise parameters of fuzzy if-then rules. Next, the linear weights of the TSK fuzzy type are estimated using the least squares estimate (LSE method. These linear weights are used as the consequent parameters in the TSK-ELM design. The experiments were performed on short-term electricity-load data for forecasting. The electricity-load data were used to forecast hourly day-ahead loads given temperature forecasts; holiday information; and historical loads from the New England ISO. In order to quantify the performance of the forecaster, we use metrics and statistical characteristics such as root mean squared error (RMSE as well as mean absolute error (MAE, mean absolute percent error (MAPE, and R-squared, respectively. The experimental results revealed that the proposed method showed good performance when compared with a conventional ELM with four activation functions such sigmoid, sine, radial basis function, and rectified linear unit (ReLU. It possessed superior prediction performance and knowledge information and a small number of rules.

  12. Measurement of the two-neutrino double-beta decay half-life of {sup 130}Te with the CUORE-0 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Alduino, C.; Avignone, F.T.; Chott, N.; Creswick, R.J.; Rosenfeld, C.; Wilson, J. [University of South Carolina, Department of Physics and Astronomy, Columbia, SC (United States); Alfonso, K.; Hickerson, K.P.; Huang, H.Z.; Liu, X.; Trentalange, S.; Zhu, B.X. [University of California, Department of Physics and Astronomy, Los Angeles, CA (United States); Artusa, D.R. [University of South Carolina, Department of Physics and Astronomy, Columbia, SC (United States); INFN-Laboratori Nazionali del Gran Sasso, Assergi, L' Aquila (Italy); Azzolini, O.; Camacho, A.; Keppel, G.; Palmieri, V.; Pira, C. [INFN-Laboratori Nazionali di Legnaro, Legnaro, Padova (Italy); Banks, T.I.; Drobizhev, A.; Freedman, S.J.; Hennings-Yeomans, R.; O' Donnell, T.; Wagaarachchi, S.L. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Bari, G.; Deninno, M.M. [INFN-Sezione di Bologna, Bologna (Italy); Beeman, J.W. [Lawrence Berkeley National Laboratory, Materials Science Division, Berkeley, CA (United States); Bellini, F.; Cardani, L.; Casali, N.; Cosmelli, C.; Ferroni, F. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN-Sezione di Roma, Rome (Italy); Bersani, A.; Caminata, A. [INFN-Sezione di Genova, Genova (Italy); Biassoni, M.; Carbone, L.; Cremonesi, O.; Ferri, E.; Giachero, A.; Pessina, G.; Previtali, E.; Rusconi, C. [INFN-Sezione di Milano Bicocca, Milan (Italy); Brofferio, C.; Capelli, S.; Carniti, P.; Cassina, L.; Chiesa, D.; Clemenza, M.; Faverzani, M.; Fiorini, E.; Gironi, L.; Gotti, C.; Maino, M.; Nucciotti, A.; Pavan, M.; Pozzi, S.; Sisti, M.; Terranova, F.; Zanotti, L. [Universita di Milano-Bicocca, Dipartimento di Fisica, Milan (Italy); INFN-Sezione di Milano Bicocca, Milan (Italy); Bucci, C.; Cappelli, L.; D' Addabbo, A.; Di Vacri, M.L.; Gorla, P.; Pattavina, L.; Pirro, S. [INFN-Laboratori Nazionali del Gran Sasso, Assergi, L' Aquila (Italy); Canonica, L. [INFN-Laboratori Nazionali del Gran Sasso, Assergi, L' Aquila (Italy); Massachusetts Institute of Technology, Cambridge, MA (United States); Cao, X.G.; Fang, D.Q.; Ma, Y.G.; Wang, H.W.; Zhang, G.Q. [Chinese Academy of Sciences, Shanghai Institute of Applied Physics, Shanghai (China); Copello, S.; Di Domizio, S.; Fernandes, G.; Marini, L.; Pallavicini, M. [INFN-Sezione di Genova, Genova (Italy); Universita di Genova, Dipartimento di Fisica, Genova (Italy); Cushman, J.S.; Davis, C.J.; Heeger, K.M.; Lim, K.E.; Maruyama, R.H. [Yale University, Department of Physics, New Haven, CT (United States); Dafinei, I.; Morganti, S.; Mosteiro, P.J.; Orio, F.; Pettinacci, V.; Tomei, C.; Vignati, M. [INFN-Sezione di Roma, Rome (Italy); Dell' Oro, S. [INFN-Laboratori Nazionali del Gran Sasso, Assergi, L' Aquila (Italy); INFN-Gran Sasso Science Institute, L' Aquila (Italy); Feintzeig, J.; Fujikawa, B.K.; Mei, Y.; Smith, A.R. [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Franceschi, M.A.; Ligi, C.; Napolitano, T.; Piperno, G. [INFN-Laboratori Nazionali di Frascati, Frascati, Rome (Italy); Giuliani, A.; Tenconi, M. [Universite Paris-Saclay, CSNSM, Univ. Paris-Sud, CNRS/IN2P3, Orsay (France); Gladstone, L.; Leder, A.; Winslow, L.A. [Massachusetts Institute of Technology, Cambridge, MA (United States); Gutierrez, T.D. [California Polytechnic State University, Physics Department, San Luis Obispo, CA (United States); Haller, E.E. [Lawrence Berkeley National Laboratory, Materials Science Division, Berkeley, CA (United States); University of California, Department of Materials Science and Engineering, Berkeley, CA (United States); Han, K. [Yale University, Department of Physics, New Haven, CT (United States); Shanghai Jiao Tong University, Department of Physics and Astronomy, Shanghai (China); Hansen, E. [University of California, Department of Physics and Astronomy, Los Angeles, CA (United States); Massachusetts Institute of Technology, Cambridge, MA (United States); Kadel, R. [Lawrence Berkeley National Laboratory, Physics Division, Berkeley, CA (United States); Kolomensky, Yu.G. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Physics Division, Berkeley, CA (United States); Martinez, M. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN-Sezione di Roma, Rome (Italy); Universidad de Zaragoza, Laboratorio de Fisica Nuclear y Astroparticulas, Zaragoza (Spain); Moggi, N. [INFN-Sezione di Bologna, Bologna (Italy); Alma Mater Studiorum-Universita di Bologna, Dipartimento di Scienze per la Qualita della Vita, Bologna (Italy); Nones, C. [Service de Physique des Particules, CEA/Saclay, Gif-sur-Yvette (France); Norman, E.B.; Wang, B.S. [Lawrence Livermore National Laboratory, Livermore, CA (United States); University of California, Department of Nuclear Engineering, Berkeley, CA (United States); Ouellet, J.L. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Massachusetts Institute of Technology, Cambridge, MA (United States); Pagliarone, C.E. [INFN-Laboratori Nazionali del Gran Sasso, Assergi, L' Aquila (Italy); Universita degli Studi di Cassino e del Lazio Meridionale, Dipartimento di Ingegneria Civile e Meccanica, Cassino (Italy); Sangiorgio, S.; Scielzo, N.D. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Santone, D. [INFN-Laboratori Nazionali del Gran Sasso, Assergi, L' Aquila (Italy); Universita dell' Aquila, Dipartimento di Scienze Fisiche e Chimiche, L' Aquila (Italy); Singh, V. [University of California, Department of Physics, Berkeley, CA (US); Taffarello, L. [INFN-Sezione di Padova, Padova (IT); Wise, T. [Yale University, Department of Physics, New Haven, CT (US); University of Wisconsin, Department of Physics, Madison, WI (US); Woodcraft, A. [University of Edinburgh, SUPA, Institute for Astronomy, Edinburgh (GB); Zimmermann, S. [Lawrence Berkeley National Laboratory, Engineering Division, Berkeley, CA (US); Zucchelli, S. [INFN-Sezione di Bologna, Bologna (IT); Alma Mater Studiorum-Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (IT)

    2017-01-15

    We report on the measurement of the two-neutrino double-beta decay half-life of {sup 130}Te with the CUORE-0 detector. From an exposure of 33.4 kg year of TeO{sub 2}, the half-life is determined to be T{sub 1/2}{sup 2ν} = [8.2 ± 0.2 (stat.) ± 0.6 (syst.)] x 10{sup 20} year. This result is obtained after a detailed reconstruction of the sources responsible for the CUORE-0 counting rate, with a specific study of those contributing to the {sup 130}Te neutrinoless double-beta decay region of interest. (orig.)

  13. The interaction between thermodynamic stability and buried free cysteines in regulating the functional half-life of fibroblast growth factor-1.

    Science.gov (United States)

    Lee, Jihun; Blaber, Michael

    2009-10-16

    Protein biopharmaceuticals are an important and growing area of human therapeutics; however, the intrinsic property of proteins to adopt alternative conformations (such as during protein unfolding and aggregation) presents numerous challenges, limiting their effective application as biopharmaceuticals. Using fibroblast growth factor-1 as model system, we describe a cooperative interaction between the intrinsic property of thermostability and the reactivity of buried free-cysteine residues that can substantially modulate protein functional half-life. A mutational strategy that combines elimination of buried free cysteines and secondary mutations that enhance thermostability to achieve a substantial gain in functional half-life is described. Furthermore, the implementation of this design strategy utilizing stabilizing mutations within the core region resulted in a mutant protein that is essentially indistinguishable from wild type as regard protein surface and solvent structure, thus minimizing the immunogenic potential of the mutations. This design strategy should be generally applicable to soluble globular proteins containing buried free-cysteine residues.

  14. Some problems of parametric neutron activation analysis based on the use of radioactive daughters of longer-lived mothers with low mother/daughter half-life ratios

    International Nuclear Information System (INIS)

    Cohen, I.M.

    2012-01-01

    The theoretical and practical aspects of the use of radioactive daughters originated from the decay of longer-lived radioactive mothers in parametric activation analysis, when the ratio: mother half-life to daughter half-life is less than 10, are discussed. The mother-daughter relationships: 47 Ca/ 47 Sc; 95 Zr/ 95 Nb; 140 Ba/ 140 La; 99 Mo/ 99m Tc and 115 Cd/ 115m In are selected as models for the study. The cases when the radionuclide of interest is formed through both direct and indirect routes are also analyzed. As illustrative example, the direct reaction and the reaction chain: 47 Ti(n,p) 47 Sc/ 46 Ca(n,γ) 47 Ca(β - ) 47 Sc are evaluated with respect to the determination of the elements involved and their reciprocal interferences. (author)

  15. Short (

    NARCIS (Netherlands)

    Telleman, Gerdien; den Hartog, Laurens

    2013-01-01

    Aim: This systematic review assessed the implant survival rate of short (<10 mm) dental implants installed in partially edentulous patients. A case report of a short implant in the posterior region have been added. Materials and methods: A search was conducted in the electronic databases of MEDLINE

  16. Entropy method combined with extreme learning machine method for the short-term photovoltaic power generation forecasting

    International Nuclear Information System (INIS)

    Tang, Pingzhou; Chen, Di; Hou, Yushuo

    2016-01-01

    As the world’s energy problem becomes more severe day by day, photovoltaic power generation has opened a new door for us with no doubt. It will provide an effective solution for this severe energy problem and meet human’s needs for energy if we can apply photovoltaic power generation in real life, Similar to wind power generation, photovoltaic power generation is uncertain. Therefore, the forecast of photovoltaic power generation is very crucial. In this paper, entropy method and extreme learning machine (ELM) method were combined to forecast a short-term photovoltaic power generation. First, entropy method is used to process initial data, train the network through the data after unification, and then forecast electricity generation. Finally, the data results obtained through the entropy method with ELM were compared with that generated through generalized regression neural network (GRNN) and radial basis function neural network (RBF) method. We found that entropy method combining with ELM method possesses higher accuracy and the calculation is faster.

  17. Pile-up corrections for high-precision superallowed β decay half-life measurements via γ-ray photopeak counting

    Science.gov (United States)

    Grinyer, G. F.; Svensson, C. E.; Andreoiu, C.; Andreyev, A. N.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Chakrawarthy, R. S.; Finlay, P.; Garrett, P. E.; Hackman, G.; Hyland, B.; Kulp, W. D.; Leach, K. G.; Leslie, J. R.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Sarazin, F.; Schumaker, M. A.; Smith, M. B.; Valiente-Dobón, J. J.; Waddington, J. C.; Williams, S. J.; Wong, J.; Wood, J. L.; Zganjar, E. F.

    2007-09-01

    A general technique that corrects γ-ray gated β decay-curve data for detector pulse pile-up is presented. The method includes corrections for non-zero time-resolution and energy-threshold effects in addition to a special treatment of saturating events due to cosmic rays. This technique is verified through a Monte Carlo simulation and experimental data using radioactive beams of Na26 implanted at the center of the 8π γ-ray spectrometer at the ISAC facility at TRIUMF in Vancouver, Canada. The β-decay half-life of Na26 obtained from counting 1809-keV γ-ray photopeaks emitted by the daughter Mg26 was determined to be T=1.07167±0.00055 s following a 27σ correction for detector pulse pile-up. This result is in excellent agreement with the result of a previous measurement that employed direct β counting and demonstrates the feasibility of high-precision β-decay half-life measurements through the use of high-purity germanium γ-ray detectors. The technique presented here, while motivated by superallowed-Fermi β decay studies, is general and can be used for all half-life determinations (e.g. α-, β-, X-ray, fission) in which a γ-ray photopeak is used to select the decays of a particular isotope.

  18. WRF model sensitivity to land surface model and cumulus parameterization under short-term climate extremes over the southern Great Plains of the United States

    Science.gov (United States)

    Lisi Pei; Nathan Moore; Shiyuan Zhong; Lifeng Luo; David W. Hyndman; Warren E. Heilman; Zhiqiu. Gao

    2014-01-01

    Extreme weather and climate events, especially short-term excessive drought and wet periods over agricultural areas, have received increased attention. The Southern Great Plains (SGP) is one of the largest agricultural regions in North America and features the underlying Ogallala-High Plains Aquifer system worth great economic value in large part due to production...

  19. Importance of neonatal FcR in regulating the serum half-life of therapeutic proteins containing the Fc domain of human IgG1: a comparative study of the affinity of monoclonal antibodies and Fc-fusion proteins to human neonatal FcR.

    Science.gov (United States)

    Suzuki, Takuo; Ishii-Watabe, Akiko; Tada, Minoru; Kobayashi, Tetsu; Kanayasu-Toyoda, Toshie; Kawanishi, Toru; Yamaguchi, Teruhide

    2010-02-15

    The neonatal FcR (FcRn) binds to the Fc domain of IgG at acidic pH in the endosome and protects IgG from degradation, thereby contributing to the long serum half-life of IgG. To date, more than 20 mAb products and 5 Fc-fusion protein products have received marketing authorization approval in the United States, the European Union, or Japan. Many of these therapeutic proteins have the Fc domain of human IgG1; however, the serum half-lives differ in each protein. To elucidate the role of FcRn in the pharmacokinetics of Fc domain-containing therapeutic proteins, we evaluated the affinity of the clinically used human, humanized, chimeric, or mouse mAbs and Fc-fusion proteins to recombinant human FcRn by surface plasmon resonance analysis. The affinities of these therapeutic proteins to FcRn were found to be closely correlated with the serum half-lives reported from clinical studies, suggesting the important role of FcRn in regulating their serum half-lives. The relatively short serum half-life of Fc-fusion proteins was thought to arise from the low affinity to FcRn. The existence of some mAbs having high affinity to FcRn and a short serum half-life, however, suggested the involvement of other critical factor(s) in determining the serum half-life of such Abs. We further investigated the reason for the relatively low affinity of Fc-fusion proteins to FcRn and suggested the possibility that the receptor domain of Fc-fusion protein influences the structural environment of the FcRn binding region but not of the FcgammaRI binding region of the Fc domain.

  20. Retrospective cohort clinical investigation of a dental implant with a narrow diameter and short length for the partial rehabilitation of extremely atrophic jaws.

    Science.gov (United States)

    Maló, Paulo S; de Araújo Nobre, Miguel A; Lopes, Armando V; Ferro, Ana S

    2017-01-01

    We investigated the short-term clinical outcomes of narrow-diameter short-length implants for the fixed-prosthetic partial rehabilitation of extremely resorbed jaws. Twenty-three patients requiring partial rehabilitations with narrow-platform short-length implants in any jaw were included in this study. In total, 30 implants 3.3 mm in diameter and 7 (n = 15 implants) or 8.5 (n = 15 implants) mm in length were inserted. The primary outcome measure was implant cumulative survival rate (CSR); the secondary outcome measures were marginal bone resorption at 1 and 3 years and the incidence of biologic and mechanical complications. Five patients (21.7%) with six implants (20%) were lost to follow-up. Two implants failed in two patients, yielding a CSR at 3 years of follow-up of 93.4%. The average (standard deviation) marginal bone resorption was 1.34 mm (0.95 mm) after the first year and 1.38 mm (0.78 mm) after the third year. Biologic complications occurred in three patients; mechanical complications occurred in three patients. Despite the limitations of the study, our findings show that the use of new narrow-diameter short-length implants for the rehabilitation of extremely atrophic regions is viable in the short-term, and can be considered a treatment alternative in extremely resorbed jaws.

  1. Some Recent Applications of Short Half-Life Radioisotopes in Australia; Quelques Applications Recentes des Radioisotopes a Courte Periode En Australie; НОВЕЙШИЕ СПОСОБЫ ИСПОЛЬЗОВАНИЯ В АВСТРАЛИИ КОРОТКОЯИВУЩИХ РАДИОИЗОТОПОВ; Algunas Recientes Aplicaciones de los Radioisotopos de Periodo Corto en Australia

    Energy Technology Data Exchange (ETDEWEB)

    Watt, J. S. [Australian Atomic Energy Commission Research Establishment, Lucas Heights, NSW (Australia)

    1963-03-15

    This paper describes the use of short-lived radioisotopes in some of the field investigations recently carried out by the Isotope Division of the Australian Atomic Energy Commission. A radioisotope technique is being developed to trace air movements in clouds, principally for use in experiments related to cloud seeding. In a series of ten experiments, various quantities up to 2 c of copper-64 as finely particulate CuO have been released from an aircraft and traced by detecting, with a large crystal scintillometer, the {gamma}-rays emitted by the CuO distributed about the aircraft. A novel feature of the method is that, not only is the amount of radioactivity about the aircraft measured, but also the directional location of the source of radiation. This enables the navigation of the aircraft towards the centre of the radioactivity. A technique is being developed for large-scale ventilation and air pollution studies. Small amounts of copper-64, either as CuO powder or as copper adsorbed on particles, would be released and collected on filter paper using a high-speed air sampler. Experiments show that excellent discrimination against natural airborne radioactivity is obtained by using {gamma}-{gamma} coincidence techniques for detecting the copper-64 positron annihilation pair. The minimum detection level is about 1 x 10{sup -18} c Cu{sup 64}/cm{sup 3} of air. A method for detection of leaks in town gas distribution systems is described. About 500 {mu}c of bromine-82 labelled methyl bromide is used to test for leaks in the individual services between the gas main and meter, and a feature of the method is that most of the radioactive gas is withdrawn after the test and can be used again. Finally, experiments are briefly described in which gold-198 was used to trace silt, effluent and water movement. (author) [French] L'auteur decrit diverses recherches au moyen des radioisotopes a courte periode entreprises recemment par la Division des isotopes de la Commission

  2. Analytical basis for neutron-activation analysis measuring nuclides with a half-life of second order

    International Nuclear Information System (INIS)

    Yonezawa, Chushiro; Ichimura, Shigeju; Matsue, Hideaki; Kurosawa, Tatsuya

    1998-01-01

    An analytical basis for a neutron-activation analysis (NAA) for measuring nuclides of second-order half-lives produced by the (n, γ) reaction has been studied using a neutron-activation analysis facility (PN-3) of JRR-3M. The NAA facility, comprising a fast pneumatic irradiation system and a high count-rate gamma-ray spectrometer, is able to automatically conduct NAA with short-lived nuclides. Basic experimental conditions, such as a high count-rate gamma-ray measurement, the effects of irradiation-capsule material and the stability of the neutron flux, were examined. The analytical sensitivities and detection limits for 20 elements of which activated radionuclide having half-lives from 0.7 to 100 s were obtained. Scandium, In, Dy and Hf were elements having the highest analytical sensitivity, with detection limits down to 4.2 to 14 ng. Fluorine, which is difficult to determine by other methods, can be detected at above 530 ng. Analytical applications of NAA with short-lived nuclides have been carried out for F, Se, Sc, Hf, In and Dy in various materials, including reference materials. The accuracy, precision and detection limits of NAA with short-lived nuclides have been evaluated. (author)

  3. Half-Life of Sulfonylureas in HNF1A and HNF4A Human MODY Patients is not Prolonged as Suggested by the Mouse Hnf1a(-/-) Model.

    Science.gov (United States)

    Urbanova, Jana; Andel, Michal; Potockova, Jana; Klima, Josef; Macek, Jan; Ptacek, Pavel; Mat'oska, Vaclav; Kumstyrova, Tereza; Heneberg, Petr

    2015-01-01

    Sulfonylurea derivatives are widely used for clinical treatment of human subjects with Maturity Onset Diabetes of the Young (MODY) caused by mutations in HNF-1α or HNF-4α despite the mechanism leading to their hypersensitivity is incompletely understood. In Hnf1a(-/-) mice, serum concentrations and half-life of sulfonylurea derivatives are strongly increased. We thus hypothesized that reduced sulfonylurea derivatives clearance stands behind their therapeutic potential in human HNF1A/HNF4A MODY subjects. Single doses of 3 mg glipizide and 5 mg glibenclamide/glyburide were administered sequentially to seven HNF1A/HNF4A MODY subjects and six control individuals matched for their age, BMI and CYP2C9 genotype. Pharmacokinetic (plasma concentration levels, Cmax, tmax, t1/2, AUC) and pharmacodynamic parameters (glycemia, C-peptide and insulin plasma levels) were followed for 24 hours after drug administration. We provide the first evidence on the pharmacokinetics and pharmacodynamics of sulfonylurea derivatives in human MODY subjects. The half-life of glipizide did not change, and reached 3.8±0.7 and 3.7±1.8 h in the MODY and control subjects, respectively. The half-life of glibenclamide was increased only in some MODY subjects (t1/2 9.5±6.7 and 5.0±1.4 h, respectively). Importantly, the intra- individual responses of MODY (but control) subjects to glipizide and glibenclamide treatment were highly correlated. With regards to pharmacodynamics, we observed a differential response of control but not MODY subjects to the doses of glipizide and glibenclamide applied. We rejected the hypothesis that all human MODY-associated mutations in HNF1A / HNF4A induce changes in the pharmacokinetics of sulfonylureas in humans analogically to the Hnf1a(-/-) mouse model.

  4. Hair-to-blood ratio and biological half-life of mercury: experimental study of methylmercury exposure through fish consumption in humans.

    Science.gov (United States)

    Yaginuma-Sakurai, Kozue; Murata, Katsuyuki; Iwai-Shimada, Miyuki; Nakai, Kunihiko; Kurokawa, Naoyuki; Tatsuta, Nozomi; Satoh, Hiroshi

    2012-02-01

    The hair-to-blood ratio and biological half-life of methylmercury in a one-compartment model seem to differ between past and recent studies. To reevaluate them, 27 healthy volunteers were exposed to methylmercury at the provisional tolerable weekly intake (3.4 µg/kg body weight/week) for adults through fish consumption for 14 weeks, followed by a 15-week washout period after the cessation of exposure. Blood was collected every 1 or 2 weeks, and hair was cut every 4 weeks. Total mercury (T-Hg) concentrations were analyzed in blood and hair. The T-Hg levels of blood and hair changed with time (p < 0.001). The mean concentrations increased from 6.7 ng/g at week 0 to 26.9 ng/g at week 14 in blood, and from 2.3 to 8.8 µg/g in hair. The mean hair-to-blood ratio after the adjustment for the time lag from blood to hair was 344 ± 54 (S.D.) for the entire period. The half-lives of T-Hg were calculated from raw data to be 94 ± 23 days for blood and 102 ± 31 days for hair, but the half-lives recalculated after subtracting the background levels from the raw data were 57 ± 18 and 64 ± 22 days, respectively. In conclusion, the hair-to-blood ratio of methylmercury, based on past studies, appears to be underestimated in light of recent studies. The crude half-life may be preferred rather than the recalculated one because of the practicability and uncertainties of the background level, though the latter half-life may approximate the conventional one.

  5. CYP2C8 activity recovers within 96 hours after gemfibrozil dosing: estimation of CYP2C8 half-life using repaglinide as an in vivo probe.

    Science.gov (United States)

    Backman, Janne T; Honkalammi, Johanna; Neuvonen, Mikko; Kurkinen, Kaisa J; Tornio, Aleksi; Niemi, Mikko; Neuvonen, Pertti J

    2009-12-01

    Gemfibrozil 1-O-beta-glucuronide is a mechanism-based inhibitor of cytochrome P450 2C8. We studied the recovery of CYP2C8 activity after discontinuation of gemfibrozil treatment using repaglinide as a probe drug, to estimate the in vivo turnover half-life of CYP2C8. In a randomized five-phase crossover study, nine healthy volunteers ingested 0.25 mg of repaglinide alone or after different time intervals after a 3-day treatment with 600 mg of gemfibrozil twice daily. The area under the plasma concentration-time curve (AUC) from time 0 to infinity of repaglinide was 7.6-, 2.9-, 1.4- and 1.0-fold compared with the control phase when it was administered 1, 24, 48, or 96 h after the last gemfibrozil dose, respectively (P gemfibrozil). Thus, a strong CYP2C8 inhibitory effect persisted even after gemfibrozil and gemfibrozil 1-O-beta-glucuronide concentrations had decreased to less than 1% of their maximum (24-h dosing interval). In addition, the metabolite to repaglinide AUC ratios indicated that significant (P gemfibrozil administration. Based on the recovery of repaglinide oral clearance, the in vivo turnover half-life of CYP2C8 was estimated to average 22 +/- 6 h (mean +/- S.D.). In summary, CYP2C8 activity is recovered gradually during days 1 to 4 after gemfibrozil discontinuation, which should be considered when CYP2C8 substrate dosing is planned. The estimated CYP2C8 half-life will be useful for in vitro-in vivo extrapolations of drug-drug interactions involving induction or mechanism-based inhibition of CYP2C8.

  6. Proposal of a new model for dose calculation due to the inhalation of Ru-222, Ru-220 and their sons with brief half-life

    International Nuclear Information System (INIS)

    Mauricio, C.L.P.

    1982-06-01

    The consequences of the radiation interactions upon the human body are studied. In order to simulate by computer the radiation interaction of the atoms of radon and thoron atoms and their Sons with a brief half life inhaled with the cells, the compartimental dosimetric model is used. The metabolic pathway of those radionuclides is described by continuous medium dynamic differential equation. The energy transfer processes are seen in details. The individual retention function is determined by bio-analysis. The results of internal dosimetry are consistents with the new international recommendations from ICRP-32. (L.F.S.) [pt

  7. Precision measurement of the half-life of {sup 90m}Nb and {sup 99m}Tc

    Energy Technology Data Exchange (ETDEWEB)

    Kikunaga, H.; Fujisawa, H.; Ooe, K. [Osaka Univ., Toyonaka (Japan). Graduate School of Science] [and others

    2011-07-01

    We have produced {sup 90m}Nb and {sup 99m}Tc in the reactions of {sup nat}Zr(p, xn){sup 90m}Nb and {sup 100}Mo({gamma}, n){sup 99}Mo, followed by disintegration to {sup 99m}Tc, respectively, and measured the halflives of these nuclides by using a reference source method. In order to determine the short half-lives of {sup 90m}Nb precisely, an on-line gas-jet system has been employed. As a result, the half-lives of these nuclides were determined with good precision on the order of magnitude of 0.1%. (orig.)

  8. Uncertainties of the 50-year wind from short time series using generalized extreme value distribution and generalized Pareto distribution

    DEFF Research Database (Denmark)

    Larsén, Xiaoli Guo; Mann, Jakob; Rathmann, Ole

    2015-01-01

    This study examines the various sources to the uncertainties in the application of two widely used extreme value distribution functions, the generalized extreme value distribution (GEVD) and the generalized Pareto distribution (GPD). The study is done through the analysis of measurements from...... as a guideline for applying GEVD and GPD to wind time series of limited length. The data analysis shows that, with reasonable choice of relevant parameters, GEVD and GPD give consistent estimates of the return winds. For GEVD, the base period should be chosen in accordance with the occurrence of the extreme wind...

  9. New AMS method to measure the atom ratio {sup 146}Sm/{sup 147}Sm for a half-life determination of {sup 146}Sm

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, N. [Tandem Accelerator Complex, Research Facility Center for Science and Technology, University of Tsukuba (Japan); Paul, M., E-mail: paul@vms.huji.ac.il [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Alcorta, M. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Bowers, M.; Collon, P. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); Deibel, C.M. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 46624 (United States); DiGiovine, B. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Goriely, S. [Universite Libre de Bruxelles, CP-226, Brussels 1050 (Belgium); Greene, J.P.; Henderson, D.J.; Jiang, C.L. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Kashiv, Y. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); Kay, B.P.; Lee, H.Y.; Marley, S.T. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Nakanishi, T. [Faculty of Chemistry, Institute of Science and Engineering, Kanazawa University (Japan); Pardo, R.C.; Patel, N.; Rehm, K.E. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Robertson, D. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); and others

    2013-01-15

    The extinct p-process nuclide {sup 146}Sm (t{sub 1/2} = 103 {+-} 5 Myr) is known to have been present in the Early-Solar System and has been proposed as an astrophysical chronometer. {sup 146}Sm is also intensely used to date meteorite and planetary differentiation processes, enhancing the importance of an accurate knowledge of the {sup 146}Sm half-life. We are engaged in a new determination of the {sup 146}Sm half-life in which the {sup 146}Sm/{sup 147}Sm atom ratio is determined by accelerator mass spectrometry at the ATLAS facility of Argonne National Laboratory. In order to reduce systematic errors in the AMS determination of the {sup 146}Sm/{sup 147}Sm ratios (in the range of 10{sup -7}-10{sup -9}), {sup 146}Sm and {sup 147}Sm ions were alternately counted in the same detector in the focal plane of a gas-filled magnet, respectively in continuous-wave and attenuated mode. Quantitative attenuation is obtained with the 12 MHz pulsed and ns-bunched ATLAS beam by chopping beam pulses with an RF sweeper in a ratio (digitally determined) down to 1:10{sup 6}. The experiments and preliminary results are discussed.

  10. Regional frequency analysis of short duration rainfall extremes using gridded daily rainfall data as co-variate

    DEFF Research Database (Denmark)

    Madsen, H.; Gregersen, Ida Bülow; Rosbjerg, Dan

    2017-01-01

    with daily measurements. The Poisson rate is positively correlated to the mean annual precipitation for all durations considered (1 min to 48 hours). The mean intensity can be assumed constant over Denmark for durations up to 1 hour. For durations larger than 1 hour the mean intensity is significantly...... correlated to the mean extreme daily precipitation. A Generalised Pareto distribution with a regional constant shape parameter is adopted. Compared to previous regional studies in Denmark a general increase in extreme rainfall intensity for durations up to 1 hour is found, whereas for larger durations both...

  11. Increased volume of distribution for recombinant activated factor VII and longer plasma-derived factor VII half-life may explain their long lasting prophylactic effect.

    Science.gov (United States)

    Mathijssen, Natascha C J; Masereeuw, Rosalinde; Holme, Pal Andre; van Kraaij, Marian G J; Laros-van Gorkom, Britta A P; Peyvandi, Flora; van Heerde, Waander L

    2013-08-01

    Prophylaxis with plasma-derived or recombinant activated factor VII is beneficial in severe factor VII deficiency. To understand why prophylactic treatment with both products is efficacious, we conducted a pharmacokinetic study. Ten factor VII deficient patients were treated with either recombinant activated (20 μg/kg) or plasma-derived (25 IU/kg) factor VII in a cross-over design. Pharmacokinetic parameters were analyzed through activated factor VII activity, factor VII clotting activity, and factor VII antigen levels on depicted time points. Factor VII activity half-lifes, determined by non-compartmental and one-compartmental analysis (results in brackets), were shorter for recombinant activated (1.4h; 0.7h) than for plasma-derived factor VII (6.8h; 3.2h); both recombinant activated (5.1h; 2.1h and plasma-derived factor VII (5.8h; 3.2h) resulted in longer half-lives of factor VII antigen. Activated factor VII half-lives (based on activated factor VII activity levels) were significantly higher compared to factor VII clotting activity (1.6h; 0.9h). Volumes of distribution were significantly higher for activated factor VII (236 ml/kg; 175 ml/kg, measured by activated factor VII) as compared to plasma-derived factor VII (206 ml/kg; 64 ml/kg, measured by factor FVII activity), suggesting a plasma- and extracellular fluid distribution for recombinant activated factor VII. Recombinant activated factor VII showed significantly shorter half-lifes than plasma-derived factor VII. Volumes of distribution were significantly higher for treatment with recombinant activated factor VII. The longer half-life for plasma-derived factor VII, compared to recombinant activated factor VII, and the increased volume of distribution for recombinant activated factor VII, compared to plasma-derived factor VII may further elucidate the beneficial effect of prophylactic treatment of both products. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Goiania radiation accident: 30 years - a half-life for a whole life..; Acidente radiológico em Goiânia: 30 - anos - uma meia-vida para uma vida inteira...

    Energy Technology Data Exchange (ETDEWEB)

    Reis, R.G.; Lucena, E.A.; Arantes, R.R.; Silva, A.A.; Reis, A.A., E-mail: rocio@ird.gov.br [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Serviço de Ensino

    2017-07-01

    The radiological accident in Goiânia, Brazil, considered the largest urban radiological accident in the world, generated several publications in the technical area that are widely disseminated in the scientific literature, given the importance of the lessons learned. However, in a simple conversation with people who worked on that accident, it is noted that many reports have not been recorded. In this year in which 30 years of the event is completed, it will be of great value to record personal testimonies that are not in technical or scientific books. And what can we tell after a half-life that lasted for a lifetime? The lived stories, the situations, the improvisations, the way to solve, the overcoming, the human side, the emotions, happy or sad, short or long, funny or not. The objective of this work is to preserve, maintain and divulge reports and situations experienced by people who worked on the radiological accident with Cs-137 in Goiânia. Audio or video recordings about experiences lived in Goiânia by people who worked in that emergency situation were carried out. The reports are free and the form of registration is always at the discretion of the narrator. Storing records allows to preserve, maintain, and disclose the accident to other generations.

  13. Short-term effects of upper extremity circuit resistance training on muscle strength and functional independence in patients with paraplegia.

    Science.gov (United States)

    Yildirim, Adem; Sürücü, Gülseren Dost; Karamercan, Ayşe; Gedik, Dilay Eken; Atci, Nermin; Dülgeroǧlu, Deniz; Özgirgin, Neşe

    2016-11-21

    A number of exercises to strengthen the upper extremities are recommended to increase functional independence and quality of life (QoL) in patients with paraplegia. Circuit resistance training (CRT) is a type of progressive resistive exercise performed repeatedly at fixed mechanical exercise stations. The aim of this study was to investigate the potential benefits of CRT for upper extremity muscle strength, functional independence, and QoL in patients with paraplegia. Twenty-six patients with paraplegia who were participating in a conventional rehabilitation program at a tertiary education and research hospital were enrolled in this study. The participants were randomly assigned to two groups. The exercise group participated in the CRT program, which consisted of repetitive exercises for the upper extremities performed at fixed mechanical stations 5 sessions per week for 6 weeks, in addition to conventional rehabilitation. Participants in the control group received only conventional rehabilitation over the same period. We compared the groups with respect to QoL, as well as isokinetic muscle test outcomes in the upper extremities, using the Functional Independence Measure (FIM) and Borg's scale. We observed significant increases in scores on the physical component of the FIM, Borg's scale, and QoL in both the exercise and control groups. Furthermore, the large majority of isokinetic values were significantly more improved in the exercise group compared to the control group. When post-treatment outcomes were compared between the groups, improvements in scores on the physical component of the FIM and in most isokinetic values were significantly greater in the exercise group. This study showed that CRT has positive effects on muscle strength in the upper extremities and the physical disability components of the FIM when added to conventional rehabilitation programs for paraplegic patients. However, we observed no significant improvement in QoL scores after adding CRT

  14. Purification of a 166mHo solution by successive high-performance liquid chromatography and gravitational chromatography for half-life determination

    International Nuclear Information System (INIS)

    Florence Gueguen; Helene Isnard; Carole Bresson; Celine Caussignac; Guillaume Stadelmann; Anthony Nonell; Sebastien Mialle; Karsten Kossert; Frederic Chartier

    2014-01-01

    A methodology to purify a 166m Ho solution has been developed by a combination of activity and mass concentration measurements in order to further determine the 166m Ho half-life. The isobaric interference at m/q ≃ 166 requires Ho purification from non-natural Er with a high purification degree due to the large amount of Ho as opposed to Er. The Ho/Er separation was achieved using high-performance liquid chromatography on a semi-preparative column followed by purification on gravitational chromatography. The efficiency of the separation was evaluated after precise determination of the Er isotopic composition. The purification methodology enabled to separate Ho from Er. (author)

  15. The analysis of predictability of α-decay half-life formulae and the α partial half-lives of some exotic nuclei

    International Nuclear Information System (INIS)

    Dasgupta-Schubert, N.; Reyes, M.A.; Tamez, V.A.

    2009-01-01

    The predictabilities of the three α-decay half-life formulae, the Royer GLDM, the Viola-Seaborg and the Sobiczewski-Parkhomenko formulae, have been evaluated by developing a method based on the ansatz of standard experimental benchmarking. The coefficients of each formula were re-derived using the reliable data of the α -standards nuclei. The modified formulae that resulted were used to evaluate the accuracies of the formulae towards the prediction of half-lives of a set of nuclides with well-studied α spectroscopic data as well as a set of exotic α emitters. Further, a simple linear optimisation of the modified formulae allowed adjustments for the insufficient statistics of the primary data set without changing the modified formulae. While the three modified formulae showed equivalent results for all the medium heavy nuclei except the odd-odd, the modified GLDM showed relatively the best figures of merit for the odd-odd and superheavy nuclides. (orig.)

  16. Half-life Measurements of {sup 6}He, {sup 16}N, {sup 19}O, {sup 20}F, {sup 28}Al, {sup 77m}Se and {sup 1}

    Energy Technology Data Exchange (ETDEWEB)

    Konijn, J; Malmskog, S

    1962-06-15

    The half-life of different isotopes, activated by neutrons in the reactor R2-0 by means of a pneumatic rabbit, have been measured with a pulse height analyzer working in its multiscale mode of operation. A Nal(Tl)-scintillation spectrometer was used as detector. Least squares analysis calculated by the Mercury computer were performed for each measurement. The following weighted mean values of the half-lives are obtained {sup 6}He: 0.862 {+-} 0.017 sec.; {sup 16}N: 7.31 {+-} 0.04 sec.; {sup 19}O: 29.1 {+-} 0.3 sec.; {sup 20}F: 11.56 {+-} 0.05 sec.; {sup 28}Al: 2.31 {+-} 0.01 min.; {sup 77m}Se: 18.83 - 0.04 sec.; and {sup 110}Ag: 24.42 {+-} 0.14 sec.

  17. The effective and environmental half-life of {sup 137}Cs at Coral Islands at the former US nuclear test site

    Energy Technology Data Exchange (ETDEWEB)

    Robison, William L. E-mail: robison1@llnl.gov; Conrado, Cynthia L.; Bogen, Kenneth T.; Stoker, A. Carol

    2003-07-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 ({sup 137}Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of {sup 137}Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of {sup 137}Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of {sup 137}Cs and {sup 90}Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of {sup 137}Cs and {sup 90}Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of {sup 137}Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the {sup 137}Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the {sup 137}Cs/{sup 90}Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the {sup 137}Cs/{sup 90}Sr ratios in soil in 1987 relative to the{sup 137}Cs/{sup 90}Sr ratios at the time of deposition in 1954 is less

  18. Effect of short-term subaerial exposure on the cauliflower coral, Pocillopora damicornis, during a simulated extreme low-tide event

    KAUST Repository

    Castrilló n-Cifuentes, Ana Lucia; Lozano-Corté s, Diego; Zapata, Fernando A.

    2017-01-01

    There is increased interest in understanding how stress reduces coral resistance to disturbances and how acclimatization increases the ability of corals to resist future stress. Most extreme low tides at Gorgona Island, which expose reef flats to air, do not appear to negatively affect corals because corals usually do not undergo lethal bleaching during such events. However, coral physiology and fitness may be impacted by this phenomenon. The aim of this study was to evaluate whether corals exposed to air have modified biological functions to resist bleaching. To test this, an extreme low-tide event was simulated in the field. Colonies of Pocillopora damicornis were exposed to air for 15 or 40 min over the course of one, two, or three consecutive days. This procedure was repeated for one to three months. Colonies of P. damicornis exposed to air had reduced fecundity, decreased zooxanthellae density, and changed color from darker to lighter. However, the growth rate of exposed corals was similar to that of non-exposed colonies. We conclude that short periods of subaerial exposure during extreme low tides are not lethal to P. damicornis, but negatively affect sexual reproduction, which might have deleterious effects at the population level. The periodic occurrence of extreme low tides in the tropical eastern Pacific may be one factor responsible for the high rate of asexual reproduction (e.g., fragmentation) in pocilloporid corals of this region.

  19. Effect of short-term subaerial exposure on the cauliflower coral, Pocillopora damicornis, during a simulated extreme low-tide event

    KAUST Repository

    Castrillón-Cifuentes, Ana Lucia

    2017-02-06

    There is increased interest in understanding how stress reduces coral resistance to disturbances and how acclimatization increases the ability of corals to resist future stress. Most extreme low tides at Gorgona Island, which expose reef flats to air, do not appear to negatively affect corals because corals usually do not undergo lethal bleaching during such events. However, coral physiology and fitness may be impacted by this phenomenon. The aim of this study was to evaluate whether corals exposed to air have modified biological functions to resist bleaching. To test this, an extreme low-tide event was simulated in the field. Colonies of Pocillopora damicornis were exposed to air for 15 or 40 min over the course of one, two, or three consecutive days. This procedure was repeated for one to three months. Colonies of P. damicornis exposed to air had reduced fecundity, decreased zooxanthellae density, and changed color from darker to lighter. However, the growth rate of exposed corals was similar to that of non-exposed colonies. We conclude that short periods of subaerial exposure during extreme low tides are not lethal to P. damicornis, but negatively affect sexual reproduction, which might have deleterious effects at the population level. The periodic occurrence of extreme low tides in the tropical eastern Pacific may be one factor responsible for the high rate of asexual reproduction (e.g., fragmentation) in pocilloporid corals of this region.

  20. Effect of short-term subaerial exposure on the cauliflower coral, Pocillopora damicornis, during a simulated extreme low-tide event

    Science.gov (United States)

    Castrillón-Cifuentes, Ana Lucia; Lozano-Cortés, Diego F.; Zapata, Fernando A.

    2017-06-01

    There is increased interest in understanding how stress reduces coral resistance to disturbances and how acclimatization increases the ability of corals to resist future stress. Most extreme low tides at Gorgona Island, which expose reef flats to air, do not appear to negatively affect corals because corals usually do not undergo lethal bleaching during such events. However, coral physiology and fitness may be impacted by this phenomenon. The aim of this study was to evaluate whether corals exposed to air have modified biological functions to resist bleaching. To test this, an extreme low-tide event was simulated in the field. Colonies of Pocillopora damicornis were exposed to air for 15 or 40 min over the course of one, two, or three consecutive days. This procedure was repeated for one to three months. Colonies of P. damicornis exposed to air had reduced fecundity, decreased zooxanthellae density, and changed color from darker to lighter. However, the growth rate of exposed corals was similar to that of non-exposed colonies. We conclude that short periods of subaerial exposure during extreme low tides are not lethal to P. damicornis, but negatively affect sexual reproduction, which might have deleterious effects at the population level. The periodic occurrence of extreme low tides in the tropical eastern Pacific may be one factor responsible for the high rate of asexual reproduction (e.g., fragmentation) in pocilloporid corals of this region.

  1. A Novel Hybrid Model Based on Extreme Learning Machine, k-Nearest Neighbor Regression and Wavelet Denoising Applied to Short-Term Electric Load Forecasting

    Directory of Open Access Journals (Sweden)

    Weide Li

    2017-05-01

    Full Text Available Electric load forecasting plays an important role in electricity markets and power systems. Because electric load time series are complicated and nonlinear, it is very difficult to achieve a satisfactory forecasting accuracy. In this paper, a hybrid model, Wavelet Denoising-Extreme Learning Machine optimized by k-Nearest Neighbor Regression (EWKM, which combines k-Nearest Neighbor (KNN and Extreme Learning Machine (ELM based on a wavelet denoising technique is proposed for short-term load forecasting. The proposed hybrid model decomposes the time series into a low frequency-associated main signal and some detailed signals associated with high frequencies at first, then uses KNN to determine the independent and dependent variables from the low-frequency signal. Finally, the ELM is used to get the non-linear relationship between these variables to get the final prediction result for the electric load. Compared with three other models, Extreme Learning Machine optimized by k-Nearest Neighbor Regression (EKM, Wavelet Denoising-Extreme Learning Machine (WKM and Wavelet Denoising-Back Propagation Neural Network optimized by k-Nearest Neighbor Regression (WNNM, the model proposed in this paper can improve the accuracy efficiently. New South Wales is the economic powerhouse of Australia, so we use the proposed model to predict electric demand for that region. The accurate prediction has a significant meaning.

  2. Comparative analysis of methods for modelling the short-term probability distribution of extreme wind turbine loads

    DEFF Research Database (Denmark)

    Dimitrov, Nikolay Krasimirov

    2016-01-01

    We have tested the performance of statistical extrapolation methods in predicting the extreme response of a multi-megawatt wind turbine generator. We have applied the peaks-over-threshold, block maxima and average conditional exceedance rates (ACER) methods for peaks extraction, combined with four...... levels, based on the assumption that the response tail is asymptotically Gumbel distributed. Example analyses were carried out, aimed at comparing the different methods, analysing the statistical uncertainties and identifying the factors, which are critical to the accuracy and reliability...

  3. Determination of half life of the pesticides chlorpyrifos (14C) in an agricultural soil of the VI region by means of the using isotopic techniques

    International Nuclear Information System (INIS)

    Camarda Rojas, Gabriela Paz

    2005-01-01

    Chlorpyrifos is an organophosphorus insecticide widely used in Chilean agriculture in the control of plagues of insects in soil and several crops. From an environmental point of view, to know the behavior and fate of Chlorpyrifos under different moisture regimes in soil is important because it contributes to optimize its use, assuring that collateral effects do not take place inside or outside the application area and in addition it specifies the optimal conditions of application to obtain better results in the treatment with the land insecticide. In this work it was studied the half life of Chlorpyrifos ( 14 C) in an agricultural soil of VI Region, by means of the use of Isotopic techniques, under two moisture regimes of 50 and 75% of the Field Capacity. The ground samples were fortified with doses of 10 mg/Kg and incubated to 20 o C and in absence of light. The dissipation of Chlorpyrifos in soil was determined during 110 days of test, through the quantification of remaining 14 CO 2 by liquid scintillation counting. Results show temporary differences in the half life for different moisture regimes, with T 1/2 of 21 and 28 days for the soil to 75 and 50% of the Field Capacity, respectively. It was studied the factors related to soil and plaguicide that could affect speed of degradation, either accelerating or inhibiting the process of dissipation of Chlorpyrifos, under the described moisture regimes. The results indicated that the fast degradation of the insecticide organophosphorus in the soil to 75% of the CC is product of biotic and abiotic processes. Between the abiotic processes the neutral hydrolysis constituted the principal route of dissipation, mainly due to the moisture content and pH presented in soil (pH 7,2). Nevertheless, factors as the high content of organic matter of the soil, low water solubility, high coefficient of adsorption and bond p=S of the Chlorpyrifos, they suggest the sorption process would inhibit hydrolysis, slowing down the

  4. Environmental Metabolic Footprinting (EMF) vs. half-life: a new and integrative proxy for the discrimination between control and pesticides exposed sediments in order to further characterise pesticides' environmental impact.

    Science.gov (United States)

    Salvia, Marie-Virginie; Ben Jrad, Amani; Raviglione, Delphine; Zhou, Yuxiang; Bertrand, Cédric

    2017-06-28

    Pesticides are regularly used for a variety of applications and are disseminated throughout the environment. These substances may have significant negative impacts. To date, the half-life, t 1/2 , was often used to study the fate of pesticides in environmental matrices (water, soil, sediment). However, this value gives limited information. First, it does not evaluate the formation of by-products, resulting in the need for additional experiments to be performed to evaluate biodegradation and biotransformation products. T 1/2 also fails to consider the chemical's impact on biodiversity. Resilience time, a new and integrative proxy, was recently proposed as an alternative to t 1/2 , with the potential to evaluate all the post-application effects of the chemical on the environment. The 'Environmental Metabolic Footprinting' (EMF) approach, giving an idea of the resilience time, was used to evaluate the impact of botanicals on soil. The goal is to optimise the EMF to study the impact of a microbial insecticide, the Bacillus thuringiensis israelensis (Bti), on sediment. The difficulty of this work lies in the commercial solution of Bti that is really complex, and this complexity yields chromatograms that are extremely difficult to interpret; t 1/2 cannot be used. No methodologies currently exist to monitor the impact of these compounds on the environment. We will test the EMF to determine if it is sensitive enough to tolerate such complex mixtures. A pure chemical insecticide, the α-cypermethrin, will be also studied. The article shows that the EMF is able to distinguish meta-metabolome differences between control and exposed (with Bti) sediments.

  5. Metabolically stable bradykinin B2 receptor agonists enhance transvascular drug delivery into malignant brain tumors by increasing drug half-life

    Directory of Open Access Journals (Sweden)

    Glen Daniel

    2009-05-01

    -lysine-bradykinin and labradimil increased the blood half-life of Gd-DTPA sufficiently enough to increase significantly the tumor tissue Gd-DTPA area under the time-concentration curve. Conclusion Metabolically stable bradykinin B2 receptor agonists, methionine-lysine-bradykinin and labradimil, enhance the transvascular delivery of small chemotherapy drugs across the BBTB of malignant gliomas by increasing the blood half-life of the co-infused drug. The selectivity of the increase in drug delivery into the malignant glioma tissue, but not into normal brain tissue or skeletal muscle tissue, is due to the inherent porous nature of the BBTB of malignant glioma microvasculature.

  6. Targeted identification of short interspersed nuclear element families shows their widespread existence and extreme heterogeneity in plant genomes.

    Science.gov (United States)

    Wenke, Torsten; Döbel, Thomas; Sörensen, Thomas Rosleff; Junghans, Holger; Weisshaar, Bernd; Schmidt, Thomas

    2011-09-01

    Short interspersed nuclear elements (SINEs) are non-long terminal repeat retrotransposons that are highly abundant, heterogeneous, and mostly not annotated in eukaryotic genomes. We developed a tool designated SINE-Finder for the targeted discovery of tRNA-derived SINEs. We analyzed sequence data of 16 plant genomes, including 13 angiosperms and three gymnosperms and identified 17,829 full-length and truncated SINEs falling into 31 families showing the widespread occurrence of SINEs in higher plants. The investigation focused on potato (Solanum tuberosum), resulting in the detection of seven different SolS SINE families consisting of 1489 full-length and 870 5' truncated copies. Consensus sequences of full-length members range in size from 106 to 244 bp depending on the SINE family. SolS SINEs populated related species and evolved separately, which led to some distinct subfamilies. Solanaceae SINEs are dispersed along chromosomes and distributed without clustering but with preferred integration into short A-rich motifs. They emerged more than 23 million years ago and were species specifically amplified during the radiation of potato, tomato (Solanum lycopersicum), and tobacco (Nicotiana tabacum). We show that tobacco TS retrotransposons are composite SINEs consisting of the 3' end of a long interspersed nuclear element integrated downstream of a nonhomologous SINE family followed by successfully colonization of the genome. We propose an evolutionary scenario for the formation of TS as a spontaneous event, which could be typical for the emergence of SINE families.

  7. Targeted Identification of Short Interspersed Nuclear Element Families Shows Their Widespread Existence and Extreme Heterogeneity in Plant Genomes[W

    Science.gov (United States)

    Wenke, Torsten; Döbel, Thomas; Sörensen, Thomas Rosleff; Junghans, Holger; Weisshaar, Bernd; Schmidt, Thomas

    2011-01-01

    Short interspersed nuclear elements (SINEs) are non-long terminal repeat retrotransposons that are highly abundant, heterogeneous, and mostly not annotated in eukaryotic genomes. We developed a tool designated SINE-Finder for the targeted discovery of tRNA-derived SINEs. We analyzed sequence data of 16 plant genomes, including 13 angiosperms and three gymnosperms and identified 17,829 full-length and truncated SINEs falling into 31 families showing the widespread occurrence of SINEs in higher plants. The investigation focused on potato (Solanum tuberosum), resulting in the detection of seven different SolS SINE families consisting of 1489 full-length and 870 5′ truncated copies. Consensus sequences of full-length members range in size from 106 to 244 bp depending on the SINE family. SolS SINEs populated related species and evolved separately, which led to some distinct subfamilies. Solanaceae SINEs are dispersed along chromosomes and distributed without clustering but with preferred integration into short A-rich motifs. They emerged more than 23 million years ago and were species specifically amplified during the radiation of potato, tomato (Solanum lycopersicum), and tobacco (Nicotiana tabacum). We show that tobacco TS retrotransposons are composite SINEs consisting of the 3′ end of a long interspersed nuclear element integrated downstream of a nonhomologous SINE family followed by successfully colonization of the genome. We propose an evolutionary scenario for the formation of TS as a spontaneous event, which could be typical for the emergence of SINE families. PMID:21908723

  8. Precision measurement of the half-life and branching ratio of the T=1/2 mirror $\\beta$-decay of $^{37}$K

    CERN Multimedia

    We propose to study the T=1/2 mirror $\\beta$-decay of $^{37}$K. Nuclear mirror $\\beta$-decay is a competitive means to test the electroweak model by means of the high-precision measurement of V$_{ud}$ element of the CKM quark mixing matrix. One key ingredient to obtain V$_{ud}$ is the force of the transition, Ft, which has to be determined with a relative precision below 10$^{−3}$. This quantity is related to the half-life T$_{1/2}$ of the decaying nucleus, the branching ratio BR for this decay and the mass difference between the mother and daughter nucleus (Q value). Another important feature is the mixing ratio $\\rho$ between the Fermi and the Gamow-Teller character of the transition. In most cases, $\\rho$ is the major contributor to the uncertainty on Ft. Available data concerning T$_{1/2}$ and BR of $^{37}$K suffer from a lack of precision that will be easily reduced by a dedicated experiment.

  9. New limit for the half-life of double beta decay of {sup 94}Zr to the first excited state of {sup 94}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Dokania, N.; Nanal, V.; Gupta, G.; Pillay, R.G.; Ghosh, C. [Tata Institute of Fundamental Research, Department of Nuclear and Atomic Physics, Mumbai (India); Pal, S. [Tata Institute of Fundamental Research, Pelletron Linac Facility, Mumbai (India); Rath, P.K. [University of Lucknow, Department of Physics, Lucknow (India); Tretyak, V.I. [Institute for Nuclear Research, Kyiv (Ukraine); Garai, A.; Krishnamoorthy, H. [Tata Institute of Fundamental Research, India-based Neutrino Observatory, Mumbai (India); Homi Bhabha National Institute, Mumbai (India); Raina, P.K. [Indian Institute of Technology, Department of Physics, Rupnagar (India); Bhushan, K.G. [Bhabha Atomic Research Centre, Technical Physics Division, Mumbai (India)

    2017-04-15

    Neutrinoless double beta decay is a phenomenon of fundamental interest in particle physics. The decay rates of double beta decay transitions to the excited states can provide input for Nuclear Transition Matrix Element calculations for the relevant two neutrino double beta decay process. It can be useful as supplementary information for the calculation of Nuclear Transition Matrix Element for the neutrinoless double beta decay process. In the present work, double beta decay of {sup 94}Zr to the 2{sup +}{sub 1} excited state of {sup 94}Mo at 871.1 keV is studied using a low background ∝ 230 cm{sup 3} HPGe detector. No evidence of this decay was found with a 232 g.y exposure of natural zirconium. The lower half-life limit obtained for the double beta decay of {sup 94}Zr to the 2{sup +}{sub 1} excited state of {sup 94}Mo is T{sub 1/2}(0ν + 2ν) > 3.4 x 10{sup 19} y at 90% C.L., an improvement by a factor of ∝ 4 over the existing experimental limit at 90% C.L. The sensitivity is estimated to be T{sub 1/2} (0ν + 2ν) > 2.0 x 10{sup 19} y at 90% C.L. using the Feldman-Cousins method. (orig.)

  10. Precision measurement of the half-life and the $\\beta$-decay Q value of the superallowed 0$^{+}\\rightarrow$ 0$^{+}\\beta$-decay of $^{38}$Ca

    CERN Multimedia

    2002-01-01

    We propose to study the $\\beta$-decay of $^{38}$Ca. In a first instance, we intend to perform a high-precision study of the half-life of this nucleus as well as a measurement of its $\\beta$-decay Q-value with ISOLTRAP. At a later stage, we propose to study its decay branches to determine the super-allowed branching ratio with high precision. These measurements are essential to improve our understanding of the theoretical corrections (in particular the $\\delta$c correction factor) needed to calculate the universal Ft value from the ft value determined for individual nuclei. For this nucleus, the correction factor is predicted to increase significantly as compared to the nine well-studied nuclei between $^{10}$C and $^{54}$Co and the model calculations used to determine the corrections, in particular the shell-model calculations, are well under control in this mass region. Therefore, the T$_{Z}$= -1 nuclei between A=18 and A=38 are ideal test cases for the correction factors which limit today the precision on t...

  11. Effective half-life of sup 131 I during treatment of autonomous thyroid disease. Untersuchungen zur effektiven Halbwertszeit des sup 131 J bei der Radiojodbehandlung der Schilddruesenautonomie

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, B.; Bares, R.; Buell, U. (Technische Hochschule Aachen (Germany, F.R.). Klinik fuer Nuklearmedizin)

    1991-06-01

    In order to compute effective half-life of {sup 131}I after application of therapeutic doses (T{sub eff}), the time course of whole-body radioactivity was evaluated retrospectively in 115 patients with benign thyroid diseases (multinodular autonomous adenoma, solitary autonomous adenoma or Graves' disease). Because of a large overlap of T{sub eff} in the various diseases analyzed, courses of all patients who did (group Ts, 24 cases) or did not (group kTs, 91 cases) receive antithyroid drugs during therapy were summarized. In group Ts a mean T{sub eff} of 5.0+-0.9 d was found which was significantly (p<0.01) lower than the mean T{sub eff} of 6.3+-0.9 d in group kTs. We believe that the mean T{sub eff} is a practical alternative in radioiodine dosimetry if an exact determination of T{sub eff} cannot be performed because of shortage of time. (orig.).

  12. Fusion to Human Serum Albumin Extends the Circulatory Half-Life and Duration of Antithrombotic Action of the Kunitz Protease Inhibitor Domain of Protease Nexin 2.

    Science.gov (United States)

    Sheffield, William P; Eltringham-Smith, Louise J; Bhakta, Varsha

    2018-01-01

    The Kunitz Protease Inhibitor (KPI) domain of protease nexin 2 (PN2) potently inhibits coagulation factor XIa. Recombinant KPI has been shown to inhibit thrombosis in mouse models, but its clearance from the murine circulation remains uncharacterized. The present study explored the pharmacokinetic and pharmacodynamic effects of fusing KPI to human serum albumin (HSA) in fusion protein KPIHSA. Hexahistidine-tagged KPI (63 amino acids) and KPIHSA (656 amino acids) were expressed in Pichia pastoris yeast and purified by nickel-chelate chromatography. Clearance profiles in mice were determined, as well as the effects of KPI or KPIHSA administration on FeCl3-induced vena cava thrombus size or carotid artery time to occlusion, respectively. Fusion to HSA increased the mean terminal half-life of KPI by 8-fold and eliminated its interaction with the low density lipoprotein receptor-related protein. KPI and KPIHSA similarly reduced thrombus size and occlusion in both venous and arterial thrombosis models when administered at the time of injury, but only KPI was effective when administered one hour before injury. Albumin fusion deflects KPI from rapid in vivo clearance without impairing its antithrombotic properties and widens its potential therapeutic window. © 2018 The Author(s). Published by S. Karger AG, Basel.

  13. Short-Term Distribution System State Forecast Based on Optimal Synchrophasor Sensor Placement and Extreme Learning Machine

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Huaiguang; Zhang, Yingchen

    2016-11-14

    This paper proposes an approach for distribution system state forecasting, which aims to provide an accurate and high speed state forecasting with an optimal synchrophasor sensor placement (OSSP) based state estimator and an extreme learning machine (ELM) based forecaster. Specifically, considering the sensor installation cost and measurement error, an OSSP algorithm is proposed to reduce the number of synchrophasor sensor and keep the whole distribution system numerically and topologically observable. Then, the weighted least square (WLS) based system state estimator is used to produce the training data for the proposed forecaster. Traditionally, the artificial neural network (ANN) and support vector regression (SVR) are widely used in forecasting due to their nonlinear modeling capabilities. However, the ANN contains heavy computation load and the best parameters for SVR are difficult to obtain. In this paper, the ELM, which overcomes these drawbacks, is used to forecast the future system states with the historical system states. The proposed approach is effective and accurate based on the testing results.

  14. Effects of short term and long term Extremely Low Frequency Magnetic Field on depressive disorder in mice: Involvement of nitric oxide pathway.

    Science.gov (United States)

    Madjid Ansari, Alireza; Farzampour, Shahrokh; Sadr, Ali; Shekarchi, Babak; Majidzadeh-A, Keivan

    2016-02-01

    Previous reports on the possible effects of Extremely Low Frequency Magnetic Fields (ELF MF) on mood have been paradoxical in different settings while no study has yet been conducted on animal behavior. In addition, it was shown that ELF MF exposure makes an increase in brain nitric oxide level. Therefore, in the current study, we aimed to assess the possible effect(s) of ELF MF exposure on mice Forced Swimming Test (FST) and evaluate the probable role of the increased level of nitric oxide in the observed behavior. Male adult mice NMRI were recruited to investigate the short term and long term ELF MF exposure (0.5 mT and 50 Hz, single 2h and 2 weeks 2h a day). Locomotor behavior was assessed by using open-field test (OFT) followed by FST to evaluate the immobility time. Accordingly, NΩ-nitro-l-arginine methyl ester 30 mg/kg was used to exert anti-depressant like effect. According to the results, short term exposure did not alter the immobility time, whereas long term exposure significantly reduces immobility time (pmice, whereas short term exposure has no significant effect. Also, reversing the anti-depressant activity of L-NAME indicates a probable increase in the brain nitric oxide. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. A Short-term ESPERTA-based Forecast Tool for Moderate-to-extreme Solar Proton Events

    Science.gov (United States)

    Laurenza, M.; Alberti, T.; Cliver, E. W.

    2018-04-01

    The ESPERTA (Empirical model for Solar Proton Event Real Time Alert) forecast tool has a Probability of Detection (POD) of 63% for all >10 MeV events with proton peak intensity ≥10 pfu (i.e., ≥S1 events, S1 referring to minor storms on the NOAA Solar Radiation Storms scale), from 1995 to 2014 with a false alarm rate (FAR) of 38% and a median (minimum) warning time (WT) of ∼4.8 (0.4) hr. The NOAA space weather scale includes four additional categories: moderate (S2), strong (S3), severe (S4), and extreme (S5). As S1 events have only minor impacts on HF radio propagation in the polar regions, the effective threshold for significant space radiation effects appears to be the S2 level (100 pfu), above which both biological and space operation impacts are observed along with increased effects on HF propagation in the polar regions. We modified the ESPERTA model to predict ≥S2 events and obtained a POD of 75% (41/55) and an FAR of 24% (13/54) for the 1995–2014 interval with a median (minimum) WT of ∼1.7 (0.2) hr based on predictions made at the time of the S1 threshold crossing. The improved performance of ESPERTA for ≥S2 events is a reflection of the big flare syndrome, which postulates that the measures of the various manifestations of eruptive solar flares increase as one considers increasingly larger events.

  16. Short-Term Absenteeism and Health Care Utilization Due to Lower Extremity Injuries Among Novice Runners: A Prospective Cohort Study.

    Science.gov (United States)

    Smits, Dirk-Wouter; Huisstede, Bionka; Verhagen, Evert; van der Worp, Henk; Kluitenberg, Bas; van Middelkoop, Marienke; Hartgens, Fred; Backx, Frank

    2016-11-01

    To describe absenteeism and health care utilization (HCU) within 6 weeks after occurrence of running-related injuries (RRIs) among novice runners and to explore differences relating to injury and personal characteristics. Prospective cohort study. Primary care. One thousand six hundred ninety-six novice runners (18-65 years) participating in a 6-week running program ("Start-to-Run"). Injury characteristics were assessed by weekly training logs and personal characteristics by a baseline questionnaire. Data on absenteeism and HCU were collected using questionnaires at 2 and 6 weeks after the RRI occurred. A total of 185 novice runners (11%) reported an RRI during the 6-week program. Of these injured novice runners, 78% reported absence from sports, whereas only 4% reported absence from work. Fifty-one percent of the injured novice runners visited a health care professional, mostly physical therapists (PTs) rather than physicians. Absenteeism was more common among women than men and was also more common with acute RRIs than gradual-onset RRIs. As regards HCU, both the variety of professionals visited and the number of PT visits were higher among runners with muscle-tendon injuries in the ankle/foot region than among those with other RRIs. Among novice runners sustaining an RRI during a 6-week running program, over three quarters reported short-term absence from sports, whereas absence from work was very limited, and over half used professional health care. Both absence and HCU are associated with injury characteristics. In future running promotion programs (eg in Start-to-Run programs), specific attention should be paid to acute injuries and to muscle-tendon injuries in the ankle/foot region.

  17. Production of well-matured compost from night-soil sludge by an extremely short period of thermophilic composting.

    Science.gov (United States)

    Nakasaki, Kiyohiko; Ohtaki, Akihito; Takemoto, Minoru; Fujiwara, Shunrokuro

    2011-03-01

    The effect of various operational conditions on the decomposition of organic material during the composting of night-soil treatment sludge was quantitatively examined. The optimum composting conditions were found to be a temperature of ca. 60°C and an initial pH value of 8. Rapid decomposition of organic matter ceased by the sixth day of composting under these optimum conditions, and the final value of the cumulative emission of carbon (E(C)), which represents the degree of organic matter decomposition, was less than 40%, indicating that the sludge contained only a small amount of easily degradable organic material. A plant growth assay using Komatsuna (Brassica campestris L. var. rapiferafroug) in a 1/5000a standard cultivation pot was then conducted for the compost at various degrees of organic matter decomposition: the raw composting material, the final compost obtained on day 6, and the 2 intermediate compost products (i.e., E(C)=10% and 20%). It was found that the larger the E(C), the greater the yield of Komatsuna growth. It was also found that 6 days of composting is sufficient to promote Komatsuna growth at the standard loading level, which is equivalent to a 1.5 g N/pot, since the promotion effect was as high as that obtained using chemical fertilizer. It can therefore be concluded that well-matured compost could be obtained in a short period of time (i.e., as early as 6 days), when night-soil sludge is composted under optimum conditions. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Studies on the mechanism of the epileptiform activity induced by U18666A. II. concentration, half-life and distribution of radiolabeled U18666A in the brain

    Energy Technology Data Exchange (ETDEWEB)

    Cenedella, R.J.; Sarkar, C.P.; Towns, L.

    1982-06-01

    The concentration, half-life, and distribution in brain of U18666A, a drug that can drastically alter cerebral lipids and induce a chronic epileptiform state, was determined following both acute and chronic drug administration. U18666A specifically labeled with tritium was prepared by custom synthesis. Brain levels of 1 x 10(-6)M and higher were reached soon after giving an acute 10-mg/kg dose (i.p. or s.c.) of U18666A containing 7-/sup 3/H-U18666A of known specific activity. A steady state concentration of 1 to 2 x 10(-6)M was reached with chronic injection of 10 mg/kg every 4th day, a treatment schedule that results in altered brain lipids and induction of epilepsy if begun soon after birth. The disappearance of U18666A from both brain and serum was described by two similar biexponential processes, a brief rapid clearance (t1/2 . 10 h) and a sustained and much slower one (t1/2 . 65 h). Brain levels of the drug were about 10 times higher than serum at all times examined. Few differences were seen in the regional distribution of radiolabeled drug in brain as determined by both direct analysis and by autoradiographic examination; but the drug did concentrate in lipid-rich subcellular fractions. For example, the synaptosome and myelin fractions each contained about 25-35% of both the total /sup 3/H-labeled drug and total lipid in whole brain. The lipid composition of these fractions was drastically altered in treated animals. In conclusion, the chronic epileptiform state induced by U18666A does not appear to involve localization of the drug in a specific brain region or particular cell type. Rather, the condition could involve localization of the drug in lipid-rich membranes and marked changes in the composition of these membranes.

  19. Distribution of ascorbate-2-sulfate and distribution, half-life and turnover rates of [1-14C]ascorbic acid in rainbow trout

    International Nuclear Information System (INIS)

    Tucker, B.W.; Halver, J.E.

    1984-01-01

    Rainbow trout (250 g) were maintained at 15 degrees C for 3 months on a low ascorbic acid diet, given [1- 14 C]ascorbic acid by gavage, then fed the NAS/NRC requirement 12 times per week. Total urine, fecal water and branchial water were collected daily from five fish placed in metabolism chambers for four successive 5-day periods. Tissue samples were analyzed for 14 C, ascorbic acid (C1) and ascorbate-2-sulfate (C2). Excretion analysis indicated t1/2 . 42 days. After 20 days, the feeding schedule was changed to 3 times per week. Fish fed 14 C were sampled after 1, 2, 3 and 4 months. The half-life in each organ except brain was inversely proportional to the dietary level of ascorbate. Concentrations of C1 and C2 in the various tissues reflected dietary intake of vitamin C. Total C (CT . C1 + C2) levels were maintained in the liver even with the low vitamin C diet. Estimates of body pool for C1 are 27-29 mg/kg. At the higher ascorbate intake CT was 92-114 mg/kg, but decreased by 34% at the lower feeding rate to 51-62 mg/kg. Data indicate that there are two or more body pools that include a store of C2, which is readily interconverted in metabolizing tissues to and from C1. Since air and water stable C2 is antiscorbutic for fish, it is the preferred form of ascorbate for fish feeds

  20. Effect of Truncating AUC at 12, 24 and 48 hr When Evaluating the Bioequivalence of Drugs with a Long Half-Life.

    Science.gov (United States)

    Moreno, Isabel; Ochoa, Dolores; Román, Manuel; Cabaleiro, Teresa; Abad-Santos, Francisco

    2016-01-01

    Bioequivalence studies of drugs with a long half-life require long periods of time for pharmacokinetic sampling. The latest update of the European guideline allows the area under the curve (AUC) truncated at 72 hr to be used as an alternative to AUC0-t as the primary parameter. The objective of this study was to evaluate the effect of truncating the AUC at 48, 24 and 12 hr on the acceptance of the bioequivalence criterion as compared with truncation at 72 hr in bioequivalence trials. The effect of truncated AUC on the within-individual coefficient of variation (CVw) and on the ratio of the formulations was also analysed. Twenty-eight drugs were selected from bioequivalence trials. Pharmacokinetic data were analysed using WinNonLin 2.0 based on the trapezoidal method. Analysis of variance (ANOVA) was performed to obtain the ratios and 90% confidence intervals for AUC at different time-points. The degree of agreement of AUC0-72 in relation to AUC0-48 and AUC0-24, according to the Landis and Koch classification, was 'almost perfect'. Statistically significant differences were observed when the CVw of AUC truncated at 72, 48 and 24 hr was compared with the CVw of AUC0-12. There were no statistically significant differences in the AUC ratio at any time-point. Compared to AUC0-72, Pearson's correlation coefficient for mean AUC, AUC ratio and AUC CVw was worse for AUC0-12 than AUC0-24 or AUC0-48. These preliminary results could suggest that AUC truncation at 24 or 48 hr is adequate to determine whether two formulations are bioequivalent. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  1. Ultrawide spectral broadening and compression of single extremely short pulses in the visible, uv-vuv, and middle infrared by high-order stimulated Raman scattering

    International Nuclear Information System (INIS)

    Kalosha, V. P.; Herrmann, J.

    2003-01-01

    We present the results of a comprehensive analytical and numerical study of ultrawide spectral broadening and compression of isolated extremely short visible, uv-vuv and middle infrared (MIR) pulses by high-order stimulated Raman scattering in hollow waveguides. Spectral and temporal characteristics of the output pulses and the mechanism of pulse compression using dispersion of the gas filling and output glass window are investigated without the slowly varying envelope approximation. Physical limitations due to phase mismatch, velocity walk off, and pump-pulse depletion as well as improvements through the use of pump-pulse sequences and dispersion control are studied. It is shown that phase-locked pulses as short as ∼2 fs in the visible and uv-vuv, and 6.5 fs in the MIR can be generated by coherent scattering in impulsively excited Raman media without the necessity of external phase control. Using pump-pulse sequences, shortest durations in the range of about 1 fs for visible and uv-vuv probe pulses are predicted

  2. Prediction of clearance, volume of distribution and half-life by allometric scaling and by use of plasma concentrations predicted from pharmacokinetic constants: a comparative study.

    Science.gov (United States)

    Mahmood, I

    1999-08-01

    Pharmacokinetic parameters (clearance, CL, volume of distribution in the central compartment, VdC, and elimination half-life, t1/2beta) predicted by an empirical allometric approach have been compared with parameters predicted from plasma concentrations calculated by use of the pharmacokinetic constants A, B, alpha and beta, where A and B are the intercepts on the Y axis of the plot of plasma concentration against time and alpha and beta are the rate constants, both pairs of constants being for the distribution and elimination phases, respectively. The pharmacokinetic parameters of cefpiramide, actisomide, troglitazone, procaterol, moxalactam and ciprofloxacin were scaled from animal data obtained from the literature. Three methods were used to generate plots for the prediction of clearance in man: dependence of clearance on body weight (simple allometric equation); dependence of the product of clearance and maximum life-span potential (MLP) on body weight; and dependence of the product of clearance and brain weight on body weight. Plasma concentrations of the drugs were predicted in man by use of A, B, alpha and beta obtained from animal data. The predicted plasma concentrations were then used to calculate CL, VdC and t1/2beta. The pharmacokinetic parameters predicted by use of both approaches were compared with measured values. The results indicate that simple allometry did not predict clearance satisfactorily for actisomide, troglitazone, procaterol and ciprofloxacin. Use of MLP or the product of clearance and brain weight improved the prediction of clearance for these four drugs. Except for troglitazone, VdC and t1/2beta predicted for man by use of the allometric approach were comparable with measured values for the drugs studied. CL, VdC and t1/2beta predicted by use of pharmacokinetic constants were comparable with values predicted by simple allometry. Thus, if simple allometry failed to predict clearance of a drug, so did the pharmacokinetic constant

  3. Characterization of the liquid argon veto of the GERDA experiment and its application for the measurement of the "7"6Ge half-life

    International Nuclear Information System (INIS)

    Wegmann, Anne Christin

    2017-01-01

    The search for neutrinoless double-beta decay (0νββ) is one of the most active fields in modern particle physics as the observation of this process would prove lepton number violation and imply new physics beyond the Standard Model of particle physics. The GERDA experiment searches for this decay by operating bare Germanium detectors, enriched in the ββ isotope "7"6Ge, in liquid argon. For the first time, a ββ-experiment combines the excellent properties of semiconductor Germanium detectors with an active background suppression technique based on the simultaneous detection of liquid argon scintillation light by photomultiplier tubes and silicon photomultipliers coupled to scintillating fibers (LAr veto). The LAr veto has been successfully operated during the first six months of Phase II of the experiment and yielded - in combination with a Germanium detector pulse shape discrimination technique - a background index of (0.7"+"1"."1_-_0_._5).10"-"3 ((cts)/(kg.keV.yr)). With an ultimate exposure of 100 kg.yr this will allow for a 0νββ-decay half-life sensitivity of the Gerda Phase II experiment of 10"2"6 yr. Double-beta decay under the emission of two neutrinos (2νββ) is a second-order process but which is allowed by the Standard Model. The excellent background reduction of the LAr veto results in an unprecedented signal-to-background ratio of 30:1 in the energy region dominated by 2νββ-decay of "7"6Ge. The remaining background after LAr veto is estimated using the suppression factor from calibration source measurements and results in a measurement of T"2"ν_1_/_2=(1.98±0.02(stat)±0.05(syst)).10"2"1 yr and T_1_/_2"2"ν=(1.92 ±0.02(stat)±0.11(syst)).10"2"1 yr based on two different detector designs and give uncertainties on the detector parameters but both with improved systematic uncertainties in comparison to earlier measurements.

  4. Characterization of the liquid argon veto of the GERDA experiment and its application for the measurement of the {sup 76}Ge half-life

    Energy Technology Data Exchange (ETDEWEB)

    Wegmann, Anne Christin

    2017-01-18

    The search for neutrinoless double-beta decay (0νββ) is one of the most active fields in modern particle physics as the observation of this process would prove lepton number violation and imply new physics beyond the Standard Model of particle physics. The GERDA experiment searches for this decay by operating bare Germanium detectors, enriched in the ββ isotope {sup 76}Ge, in liquid argon. For the first time, a ββ-experiment combines the excellent properties of semiconductor Germanium detectors with an active background suppression technique based on the simultaneous detection of liquid argon scintillation light by photomultiplier tubes and silicon photomultipliers coupled to scintillating fibers (LAr veto). The LAr veto has been successfully operated during the first six months of Phase II of the experiment and yielded - in combination with a Germanium detector pulse shape discrimination technique - a background index of (0.7{sup +1.1}{sub -0.5}).10{sup -3} ((cts)/(kg.keV.yr)). With an ultimate exposure of 100 kg.yr this will allow for a 0νββ-decay half-life sensitivity of the Gerda Phase II experiment of 10{sup 26} yr. Double-beta decay under the emission of two neutrinos (2νββ) is a second-order process but which is allowed by the Standard Model. The excellent background reduction of the LAr veto results in an unprecedented signal-to-background ratio of 30:1 in the energy region dominated by 2νββ-decay of {sup 76}Ge. The remaining background after LAr veto is estimated using the suppression factor from calibration source measurements and results in a measurement of T{sup 2ν}{sub 1/2}=(1.98±0.02(stat)±0.05(syst)).10{sup 21} yr and T{sub 1/2}{sup 2ν}=(1.92 ±0.02(stat)±0.11(syst)).10{sup 21} yr based on two different detector designs and give uncertainties on the detector parameters but both with improved systematic uncertainties in comparison to earlier measurements.

  5. Pulse shape analysis for the GERDA experiment to set a new limit on the half-life of 0νββ decay of {sup 76}Ge

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Victoria Elisabeth

    2017-01-25

    The GERDA experiment searches for neutrinoless double beta (0νββ) decay of {sup 76}Ge using high purity germanium (HPGe) detectors operated in liquid argon (LAr). The aim is to explore half-lives of the order of 10{sup 26} yr. Therefore, GERDA relies on improved active background reduction techniques such as pulse shape discrimination (PSD) in which the time structure of the germanium signals is analyzed to discriminate signal- from background-like events. Two types of HPGe detectors are operated: semi-coaxial detectors previously used in the Heidelberg-Moscow and IGEX experiments and new Broad Energy Germanium (BEGe) detectors which feature an improved energy resolution and enhanced PSD. In Phase I of the experiment, five enriched BEGe detectors were used for the first time in the search for 0νββ decay. A PSD based on a single parameter, the ratio of the maximum current amplitude over the energy A/E is applied. 83% of the background events in a 232 keV region around Q{sub ββ} are rejected with a high signal efficiency of (92.1 ± 1.9) %. The achieved background index (BI) is (5.4{sup +4.1}{sub -3.4}) . 10{sup -3} (counts)/(keV.kg.yr). This is an improvement by a factor of 10 compared to previous germanium based 0νββ experiments. Phase II of the experiment includes a major upgrade: for further background rejection, the LAr cryostat is instrumented to detect argon scintillation light. Additional 25 BEGe detectors are installed. After PSD and LAr veto a BI of (0.7{sup +1.3}{sub -0.5}) . 10{sup -3} (counts)/(keV.kg.yr) is achieved. This is the best BI achieved in 0νββ experiments so far. A frequentist statistical analysis is performed on the combined data collected in GERDA Phase I and the first Phase II release. A new limit on the half-life of 0νββ decay of {sup 76}Ge is set to T{sup 0ν}{sub 1/2}>5.3.10{sup 25} yr at 90% C.L., with a median sensitivity of T{sup 0ν}{sub 1/2}>4.0.10{sup 25} yr at 90% C.L.

  6. Reliability and validity of the Chinese version of the Short Musculoskeletal Function Assessment questionnaire in patients with skeletal muscle injury of the upper or lower extremities.

    Science.gov (United States)

    Wang, Ying; He, Zehui; Lei, Lifang; Lin, Dingkun; Li, Yajie; Wang, Gang; Zhai, Huimin; Xu, Jingli; Zhang, Guangqing; Lin, Meizhen

    2015-07-07

    The Short Musculoskeletal Function Assessment (SMFA) questionnaire is one of the most commonly used scales to evaluate functional status and quality of life (QOL) of patients with a broad range of musculoskeletal disorders. However, a Chinese version of the SMFA questionnaire for the psychometric properties of skeletal muscle injury patients in China is still lacking. The current study translated the SMFA into Chinese and assessed its reliability and validity among Chinese patients with skeletal muscle injury of the upper or lower extremities. The original SMFA was translated from English into Chinese and culturally adapted according to cross-cultural adaptation guidelines. A multicenter cross-sectional study was conducted, comprising 339 skeletal muscle injury patients (aged 20-75 years) from 4 hospitals. The SMFA, the health survey short form (SF-36) along with a region-specific questionnaire (including the disabilities of the arm, shoulder, and hand questionnaire (DASH), the hip disability and osteoarthritis outcome score (HOOS), the knee injury and osteoarthritis outcome score (KOOS), and the foot function index (FFI)) were completed according to the region of injury. Reliability was estimated from the internal consistency using Cronbach's α and validity was assessed via convergent validity, known-groups comparison, and construct validity. Cronbach's α coefficient was over 0.75 for two subscales and four categories of the SMFA, suggesting that the internal consistency reliability of the SMFA was satisfactory. Known-groups comparison showed that the dysfunction index and the bother index of the SMFA discriminated well between patients who differed in age, gender, injury location, and operation status rather than in subgroups based on the body mass index (BMI). The convergent validity of the SMFA was good, as moderate to excellent correlations were found between the subscales of the SMFA and the four subscales of SF-36 (physical function, role-physical, bodily

  7. Uracil phosphoribosyltransferase from the extreme thermoacidophilic archaebacterium Sulfolobus shibatae is an allosteric enzyme, activated by GTP and inhibited by CTP

    DEFF Research Database (Denmark)

    Linde, Lise; Jensen, Kaj Frank

    1996-01-01

    Uracil phosphoribosyltransferase, which catalyses the formation of UMP and pyrophosphate from uracil and 5-phosphoribosyl a-1-pyrophosphate (PRPP), was partly purified from the extreme thermophilic archaebacterium Sulfolobus shibatae. The enzyme required divalent metal ions for activity...... and it showed the highest activity at pH 6.4. The specific activity of the enzyme was 50-times higher at 95°C than at 37°C, but the functional half-life was short at 95°C. The activity of uracil phosphoribosyltransferase was strongly activated by GTP, which increased Vmax of the reaction by approximately 20......-fold without much effect on Km for the substrates. The concentration of GTP required for half-maximal activation was about 80 µM. CTP was a strong inhibitor and acted by raising the concentration of GTP needed for half-maximal activation of the enzyme. We conclude that uracil phosphoribosyltransferase...

  8. Towards a better prediction of peak concentration, volume of distribution and half-life after oral drug administration in man, using allometry.

    Science.gov (United States)

    Sinha, Vikash K; Vaarties, Karin; De Buck, Stefan S; Fenu, Luca A; Nijsen, Marjoleen; Gilissen, Ron A H J; Sanderson, Wendy; Van Uytsel, Kelly; Hoeben, Eva; Van Peer, Achiel; Mackie, Claire E; Smit, Johan W

    2011-05-01

    It is imperative that new drugs demonstrate adequate pharmacokinetic properties, allowing an optimal safety margin and convenient dosing regimens in clinical practice, which then lead to better patient compliance. Such pharmacokinetic properties include suitable peak (maximum) plasma drug concentration (C(max)), area under the plasma concentration-time curve (AUC) and a suitable half-life (t(½)). The C(max) and t(½) following oral drug administration are functions of the oral clearance (CL/F) and apparent volume of distribution during the terminal phase by the oral route (V(z)/F), each of which may be predicted and combined to estimate C(max) and t(½). Allometric scaling is a widely used methodology in the pharmaceutical industry to predict human pharmacokinetic parameters such as clearance and volume of distribution. In our previous published work, we have evaluated the use of allometry for prediction of CL/F and AUC. In this paper we describe the evaluation of different allometric scaling approaches for the prediction of C(max), V(z)/F and t(½) after oral drug administration in man. Twenty-nine compounds developed at Janssen Research and Development (a division of Janssen Pharmaceutica NV), covering a wide range of physicochemical and pharmacokinetic properties, were selected. The C(max) following oral dosing of a compound was predicted using (i) simple allometry alone; (ii) simple allometry along with correction factors such as plasma protein binding (PPB), maximum life-span potential or brain weight (reverse rule of exponents, unbound C(max) approach); and (iii) an indirect approach using allometrically predicted CL/F and V(z)/F and absorption rate constant (k(a)). The k(a) was estimated from (i) in vivo pharmacokinetic experiments in preclinical species; and (ii) predicted effective permeability in man (P(eff)), using a Caco-2 permeability assay. The V(z)/F was predicted using allometric scaling with or without PPB correction. The t(½) was estimated from

  9. Real-time RT-PCR analysis of mRNA decay: half-life of Beta-actin mRNA in human leukemia CCRF-CEM and Nalm-6 cell lines

    Directory of Open Access Journals (Sweden)

    Barredo Julio C

    2002-03-01

    Full Text Available Abstract Background We describe an alternative method to determine mRNA half-life (t1/2 based on the Real-Time RT-PCR procedure. This approach was evaluated by using the β-actin gene as a reference molecule for measuring of mRNA stability. Results Human leukemia Nalm-6 and CCRF-CEM cells were treated with various concentrations of Actinomycin D to block transcription and aliquots were removed periodically. Total RNA was isolated and quantified using the RiboGreen® fluorescent dye with the VersaFluor Fluorometer System. One μg of total RNA was reverse transcribed and used as template for the amplification of a region of the β-actin gene (231 bp. To generate the standard curve, serial ten-fold dilutions of the pBactin-231 vector containing the cDNA amplified fragment were employed, β-actin mRNAs were quantified by Real-Time RT-PCR using the SYBR® Green I fluorogenic dye and data analyzed using the iCycle iQ system software. Using this method, the β-actin mRNA exhibited a half-life of 6.6 h and 13.5 h in Nalm-6 and CCRF-CEM cells, respectively. The t1/2 value obtained for Nalm-6 is comparable to those estimated from Northern blot studies, using normal human leukocytes (5.5 h. Conclusions We have developed a rapid, sensitive, and reliable method based on Real-Time RT-PCR for measuring mRNA half-life. Our results confirm that β-actin mRNA half-life can be affected by the cellular growth rate.

  10. The Half-Life of Happiness: Hedonic Adaptation in the Subjective Well-Being of Poor Slum Dwellers to a Large Improvement in Housing

    OpenAIRE

    Sebastian Galiani; Paul J. Gertler; Raimundo Undurraga

    2015-01-01

    Subjective well-being may not improve in step with increases in material well-being due to hedonic adaptation, a psychological process that attenuates the long-term emotional impact of a favorable or unfavorable change in circumstances, such that people’s happiness eventually returns to a stable reference level. We use a multi-country field experiment to examine the impact of the provision of improved housing to extremely poor populations on subjective measures of well-being to test whether p...

  11. Eddy covariance flux measurements confirm extreme CH4 emissions from a Swiss hydropower reservoir and resolve their short-term variability

    Directory of Open Access Journals (Sweden)

    S. Sobek

    2011-09-01

    Full Text Available Greenhouse gas budgets quantified via land-surface eddy covariance (EC flux sites differ significantly from those obtained via inverse modeling. A possible reason for the discrepancy between methods may be our gap in quantitative knowledge of methane (CH4 fluxes. In this study we carried out EC flux measurements during two intensive campaigns in summer 2008 to quantify methane flux from a hydropower reservoir and link its temporal variability to environmental driving forces: water temperature and pressure changes (atmospheric and due to changes in lake level. Methane fluxes were extremely high and highly variable, but consistently showed gas efflux from the lake when the wind was approaching the EC sensors across the open water, as confirmed by floating chamber flux measurements. The average flux was 3.8 ± 0.4 μg C m−2 s−1 (mean ± SE with a median of 1.4 μg C m−2 s−1, which is quite high even compared to tropical reservoirs. Floating chamber fluxes from four selected days confirmed such high fluxes with 7.4 ± 1.3 μg C m−2 s−1. Fluxes increased exponentially with increasing temperatures, but were decreasing exponentially with increasing atmospheric and/or lake level pressure. A multiple regression using lake surface temperatures (0.1 m depth, temperature at depth (10 m deep in front of the dam, atmospheric pressure, and lake level was able to explain 35.4% of the overall variance. This best fit included each variable averaged over a 9-h moving window, plus the respective short-term residuals thereof. We estimate that an annual average of 3% of the particulate organic matter (POM input via the river is sufficient to sustain these large CH4 fluxes. To compensate the global warming potential associated with the CH4 effluxes from this hydropower reservoir a 1.3 to 3.7 times larger terrestrial area with net carbon dioxide uptake is needed if a European-scale compilation of grasslands, croplands and forests is taken as reference. This

  12. Background-free beta-decay half-life measurements by in-trap decay and high-resolution MR-ToF mass analysis

    Science.gov (United States)

    Wolf, R. N.; Atanasov, D.; Blaum, K.; Kreim, S.; Lunney, D.; Manea, V.; Rosenbusch, M.; Schweikhard, L.; Welker, A.; Wienholtz, F.; Zuber, K.

    2016-06-01

    In-trap decay in ISOLTRAP's radiofrequency quadrupole (RFQ) ion beam cooler and buncher was used to determine the lifetime of short-lived nuclides. After various storage times, the remaining mother nuclides were mass separated from accompanying isobaric contaminations by the multi-reflection time-of-flight mass separator (MR-ToF MS), allowing for a background-free ion counting. A feasibility study with several online measurements shows that the applications of the ISOLTRAP setup can be further extended by exploiting the high resolving power of the MR-ToF MS in combination with in-trap decay and single-ion counting.

  13. Teduglutide for the treatment of short bowel syndrome

    DEFF Research Database (Denmark)

    Jeppesen, P B

    2013-01-01

    Glucagon-like peptide 2 (GLP-2) decreases gastric and intestinal motility, reduces gastric secretions, promotes intestinal growth and improves post-resection structural and functional adaptation in short bowel syndrome (SBS). Teduglutide, an analogue of GLP-2, has a prolonged half-life and provides...

  14. Whole-genome analysis of mRNA decay in Plasmodium falciparum reveals a global lengthening of mRNA half-life during the intra-erythrocytic development cycle.

    Science.gov (United States)

    Shock, Jennifer L; Fischer, Kael F; DeRisi, Joseph L

    2007-01-01

    The rate of mRNA decay is an essential element of post-transcriptional regulation in all organisms. Previously, studies in several organisms found that the specific half-life of each mRNA is precisely related to its physiologic role, and plays an important role in determining levels of gene expression. We used a genome-wide approach to characterize mRNA decay in Plasmodium falciparum. We found that, globally, rates of mRNA decay increase dramatically during the asexual intra-erythrocytic developmental cycle. During the ring stage of the cycle, the average mRNA half-life was 9.5 min, but this was extended to an average of 65 min during the late schizont stage of development. Thus, a major determinant of mRNA decay rate appears to be linked to the stage of intra-erythrocytic development. Furthermore, we found specific variations in decay patterns superimposed upon the dominant trend of progressive half-life lengthening. These variations in decay pattern were frequently enriched for genes with specific cellular functions or processes. Elucidation of Plasmodium mRNA decay rates provides a key element for deciphering mechanisms of genetic control in this parasite, by complementing and extending previous mRNA abundance studies. Our results indicate that progressive stage-dependent decreases in mRNA decay rate function are a major determinant of mRNA accumulation during the schizont stage of intra-erythrocytic development. This type of genome-wide change in mRNA decay rate has not been observed in any other organism to date, and indicates that post-transcriptional regulation may be the dominant mechanism of gene regulation in P. falciparum.

  15. Sub-nanosecond Half-life Measurement of the Yrast I{sup π}=5{sup −} State in the N=78 Nucleus {sup 136}{sub 58}Ce using Fast-timing Coincident Gamma-ray Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Alharbi, T. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Department of Physics, Faculty of Science in Zulfi, Almajmaah University, P.O. Box 1712, 11932 (Saudi Arabia); Regan, P.H., E-mail: p.regan@surrey.ac.uk [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); National Physical Laboratory, Teddington, Middlesex, TW11 0LW (United Kingdom); Mărginean, N. [Horia Hulubei – National Institute for Physics and Nuclear Engineering (IFIN-HH), Bucharest (Romania); Podolyák, Zs.; Bajoga, A.; Britton, R. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Bucurescu, D.; Deleanu, D.; Filipescu, D.; Ghită, D.; Glodariu, T.; Mihai, C. [Horia Hulubei – National Institute for Physics and Nuclear Engineering (IFIN-HH), Bucharest (Romania); Mulholland, K. [School of Engineering, University of the West of Scotland, High Street, Paisley PA1 2BE (United Kingdom); Mărginean, R.; Negret, A.; Nita, C.R. [Horia Hulubei – National Institute for Physics and Nuclear Engineering (IFIN-HH), Bucharest (Romania); Patel, Z. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Roberts, O.J. [School of Computing Engineering and Mathematics, University of Brighton, Brighton, BN2 4GJ (United Kingdom); Stroe, L.; Sava, T. [Horia Hulubei – National Institute for Physics and Nuclear Engineering (IFIN-HH), Bucharest (Romania); and others

    2014-06-15

    We report on the measurement of the half-life of the yrast I{sup π}=5{sup −} state in the transitional nucleus {sup 136}Ce using a combined HPGe-LaBr3(Ce) scintillator gamma-ray detection array. The measured value for the E1 decay is approximately half a nanosecond, which corresponds to an E1 decay strength of approximately 2×10{sup −6} Wu. This value is in line with single-particle type E1 decays in this mass region and suggests no sign of additional K-hindrance associated with axially symmetric quadrupole deformations observed for lighter cerium isotopes.

  16. Very short-term reactive forecasting of the solar ultraviolet index using an extreme learning machine integrated with the solar zenith angle.

    Science.gov (United States)

    Deo, Ravinesh C; Downs, Nathan; Parisi, Alfio V; Adamowski, Jan F; Quilty, John M

    2017-05-01

    Exposure to erythemally-effective solar ultraviolet radiation (UVR) that contributes to malignant keratinocyte cancers and associated health-risk is best mitigated through innovative decision-support systems, with global solar UV index (UVI) forecast necessary to inform real-time sun-protection behaviour recommendations. It follows that the UVI forecasting models are useful tools for such decision-making. In this study, a model for computationally-efficient data-driven forecasting of diffuse and global very short-term reactive (VSTR) (10-min lead-time) UVI, enhanced by drawing on the solar zenith angle (θ s ) data, was developed using an extreme learning machine (ELM) algorithm. An ELM algorithm typically serves to address complex and ill-defined forecasting problems. UV spectroradiometer situated in Toowoomba, Australia measured daily cycles (0500-1700h) of UVI over the austral summer period. After trialling activations functions based on sine, hard limit, logarithmic and tangent sigmoid and triangular and radial basis networks for best results, an optimal ELM architecture utilising logarithmic sigmoid equation in hidden layer, with lagged combinations of θ s as the predictor data was developed. ELM's performance was evaluated using statistical metrics: correlation coefficient (r), Willmott's Index (WI), Nash-Sutcliffe efficiency coefficient (E NS ), root mean square error (RMSE), and mean absolute error (MAE) between observed and forecasted UVI. Using these metrics, the ELM model's performance was compared to that of existing methods: multivariate adaptive regression spline (MARS), M5 Model Tree, and a semi-empirical (Pro6UV) clear sky model. Based on RMSE and MAE values, the ELM model (0.255, 0.346, respectively) outperformed the MARS (0.310, 0.438) and M5 Model Tree (0.346, 0.466) models. Concurring with these metrics, the Willmott's Index for the ELM, MARS and M5 Model Tree models were 0.966, 0.942 and 0.934, respectively. About 57% of the ELM model

  17. Operating characteristics of a partial-block randomized crossover bioequivalence study for dutasteride, a drug with a long half-life: investigation through simulation and comparison with final results.

    Science.gov (United States)

    Cai, Gengqian; Thiessen, Jake J; Baidoo, Charlotte A; Fossler, Michael J

    2010-10-01

    Studies to establish bioequivalence (BE) of a drug are important elements in support of drug applications. A typical BE study is conducted as a single dose, randomized, 2-period crossover design. For drugs with long half lives (≥ 48 hours) and evaluation of multiple BE objectives in 1 trial, this design may not be adequate. A parallel design may then be a more appropriate choice. However, parallel designs require increased sample size, which can become substantial. One option that is a compromise between the complete randomized block design and the parallel design is a partial-block crossover design. This approach came about during the development of a combination of dutasteride and tamsulosin. Previous experience with performing single-dose dutasteride studies suggested that 28 days of washout is needed between treatments because of its half-life of 7-9 days. Simulations were performed to assess the operating characteristics of this design using a previously developed PK model. Four scenarios were developed, and each scenario was simulated 500 times. The results showed that this design demonstrated acceptable consumer and producer risk. Partial-block crossover designs should be considered for studies when the half-life of the drug is long and there are more than 2 periods.

  18. Short-term effects of teriparatide versus placebo on bone biomarkers, structure, and fracture healing in women with lower-extremity stress fractures: A pilot study

    Directory of Open Access Journals (Sweden)

    Ellen A. Almirol

    2016-09-01

    Conclusions: In this randomized, pilot study, brief administration of TPTD showed anabolic effects that TPTD may help hasten fracture healing in premenopausal women with lower-extremity stress fractures. Larger prospective studies are warranted to determine the effects of TPTD treatment on stress fracture healing in premenopausal women.

  19. A short-term extremely low frequency electromagnetic field exposure increases circulating leukocyte numbers and affects HPA-axis signaling in mice

    NARCIS (Netherlands)

    Kleijn, de Stan; Ferwerda, Gerben; Wiese, Michelle; Trentelman, Jos; Cuppen, Jan; Kozicz, Tamas; Jager, de Linda; Hermans, Peter W.M.; Kemenade, van Lidy

    2016-01-01

    There is still uncertainty whether extremely low frequency electromagnetic fields (ELF-EMF) can induce health effects like immunomodulation. Despite evidence obtained in vitro, an unambiguous association has not yet been established in vivo. Here, mice were exposed to ELF-EMF for 1, 4, and 24

  20. Influence of antithyroid medication on effective half-life and uptake of {sup 131}I following radioiodine therapy; Einfluss thyreostatischer Medikation beim Morbus Basedow auf die Kinetik von 131-Iod waehrend einer Radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Moka, D.; Voth, E.; Schicha, H. [Koeln Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    1997-12-01

    Aim of this study was to assess the influence of antithyroid drugs (ADT) on the kinetics of {sup 131}I. Therefore, 56 patients with Graves` disease and with shortened effective half-life of {sup 131}I were examined under stationary conditionary conditions. In 38 patients ATD was stopped three days after radioiodine therapy (RIT). The progress of the first RIT and of a second RIT, which still was necessary in 12 patients, was compared to 18 patients receiving ATD continuously. Values of effective half-life for {sup 131}I rose significantly from 3.4 to 5.7 days 2-3 days after stopping ATD. There was an increase of the {sup 131}I-uptake of a second RIT after stopping ATD from 29.0 to 38.4%. In contrast, {sup 131}I-uptake of a second RIT decreased significantly in patients receiving ATD continuously. Effective half-life and uptake of {sup 131}I were affected significantly by ATD. Interrupting ATD after RIT is useful to improve an apparantly insufficient RIT in thyrotoxic patients receiving ATD. (orig.) [Deutsch] Ziel dieser Studie war es, beim M. Basedow die Kinetik von {sup 131}I unter dem Einfluss thyreostatischer Medikation (tM) zu untersuchen. Dazu wurden die 56 Patienten mit immunogener Hyperthyreose M. Basedow (MB) und mit einem erhoehten `turn over` von {sup 131}I unter tM untersucht. Bei 38 Patienten wurde die tM am 3. Tag nach RITh abgesetzt. Der Verlauf der 1. RITh bzw. einer Nachtherapie wurde mit 18 Patienten unter fortlaufender tM verglichen. 2-3 Tage nach Absetzen der tM stieg die effektive Halbwertzeit (HWZ{sub eff.}) von {sup 131}I signifikant von 3,4 auf 5,7 Tage und der {sup 131}I-Uptake bei der Nachtherapie von 29,0 auf 38,4% an, waehrend er unter fortlaufender tM signifikant abfiel. Beide Effekte zeigen, dass tM die {sup 131}I-Kinetik der Schilddruese sehr schnell beeinflussen kann. Gezieltes Absetzen der tM eignet sich deshalb, um bei ausgewaehlten Patienten eine primaer unzureichende RITh noch waehrend des stationaeren Aufenthaltes zu steuern und

  1. Half-life Measurements of {sup 6}He, {sup 16}N, {sup 19}O, {sup 20}F, {sup 28}Al, {sup 77m}Se and {sup 110}Ag

    Energy Technology Data Exchange (ETDEWEB)

    Konijn, J; Malmskog, S

    1962-06-15

    The half-life of different isotopes, activated by neutrons in the reactor R2-0 by means of a pneumatic rabbit, have been measured with a pulse height analyzer working in its multiscale mode of operation. A Nal(Tl)-scintillation spectrometer was used as detector. Least squares analysis calculated by the Mercury computer were performed for each measurement. The following weighted mean values of the half-lives are obtained {sup 6}He: 0.862 {+-} 0.017 sec.; {sup 16}N: 7.31 {+-} 0.04 sec.; {sup 19}O: 29.1 {+-} 0.3 sec.; {sup 20}F: 11.56 {+-} 0.05 sec.; {sup 28}Al: 2.31 {+-} 0.01 min.; {sup 77m}Se: 18.83 - 0.04 sec.; and {sup 110}Ag: 24.42 {+-} 0.14 sec.

  2. Treatment of short-lived radioactive wastes

    International Nuclear Information System (INIS)

    Yamaguchi, Chiri

    1976-01-01

    Recently short life nuclides have come to be utilized increasingly as diagnostic radioisotopes, and Tc-99m (half-life; 6.05 hours) and Ga-67 (half-life 7.79 hours) are replacing the most nuclides fomerly used in vivo test. Such development of radioactive products inevitably causes the rapid increase of their wastes. At present, the radioactive wastes produced by hospitals and university laboratories in Japan are collected by the Japan Radioisotope Association, and treated by the Japan Atomic Energy Research Institute. These wastes are divided into combustibles and incombustibles to store in the store house in the Japan Atomic Energy Research Institute. The present law in Japan contains the contradiction which treats the matter with one several millionth of radioactivity after decay same as the original radioactive matter. Thus solid must be stored permanently, while gas and liquid can be discharged after dilution. (Kobatake, H.)

  3. Anterior corpectomy via the mini-open, extreme lateral, transpsoas approach combined with short-segment posterior fixation for single-level traumatic lumbar burst fractures: analysis of health-related quality of life outcomes and patient satisfaction.

    Science.gov (United States)

    Theologis, Alexander A; Tabaraee, Ehsan; Toogood, Paul; Kennedy, Abbey; Birk, Harjus; McClellan, R Trigg; Pekmezci, Murat

    2016-01-01

    The authors present clinical outcome data and satisfaction of patients who underwent minimally invasive vertebral body corpectomy and cage placement via a mini-open, extreme lateral, transpsoas approach and posterior short-segment instrumentation for lumbar burst fractures. Patients with unstable lumbar burst fractures who underwent corpectomy and anterior column reconstruction via a mini-open, extreme lateral, transpsoas approach with short-segment posterior fixation were reviewed retrospectively. Demographic information, operative parameters, perioperative radiographic measurements, and complications were analyzed. Patient-reported outcome instruments (Oswestry Disability Index [ODI], 12-Item Short Form Health Survey [SF-12]) and an anterior scar-specific patient satisfaction questionnaire were recorded at the latest follow-up. Twelve patients (7 men, 5 women, average age 42 years, range 22-68 years) met the inclusion criteria. Lumbar corpectomies with anterior column support were performed (L-1, n = 8; L-2, n = 2; L-3, n = 2) and supplemented with short-segment posterior instrumentation (4 open, 8 percutaneous). Four patients had preoperative neurological deficits, all of which improved after surgery. No new neurological complications were noted. The anterior incision on average was 6.4 cm (range 5-8 cm) in length, caused mild pain and disability, and was aesthetically acceptable to the large majority of patients. Three patients required chest tube placement for pleural violation, and 1 patient required reoperation for cage subsidence/hardware failure. Average clinical follow-up was 38 months (range 16-68 months), and average radiographic follow-up was 37 months (range 6-68 months). Preoperative lumbar lordosis and focal lordosis were significantly improved/maintained after surgery. Patients were satisfied with their outcomes, had minimal/moderate disability (average ODI score 20, range 0-52), and had good physical (SF-12 physical component score 41.7% ± 10

  4. Premature Epiphyseal Closure of the Lower Extremities Contributing to Short Stature after cis-Retinoic Acid Therapy in Medulloblastoma: A Case Report.

    Science.gov (United States)

    Noyes, Jessica J; Levine, Michael A; Belasco, Jean B; Mostoufi-Moab, Sogol

    2016-01-01

    Prolonged cis-retinoic acid (RA) exposure contributes to premature epiphyseal closure. cis-RA is administered in various treatment regimens for pediatric cancers, thus increasing the risk for bone deformities and compromised growth. We present a case of premature epiphyseal closure in a 9-year-old female with a history of medulloblastoma and treatment with a multimodal regimen including cis-RA. She was subsequently diagnosed with radiation-induced endocrine late effects including hypothyroidism and growth hormone deficiency (GHD). Seven months after initiation of GH therapy, an increased prominence of the wrists and knees combined with a deceleration in growth velocity prompted further evaluation; radiographs revealed bilateral premature closure of the distal femur and proximal tibia growth plates despite normal left wrist bone age. High doses of vitamin A and its analogs are linked to premature closure of the lower-extremity growth plates in animals and children. Pediatric brain tumor patients are at increased risk of growth failure due to concurrent radiation-induced GHD, damage to the spinal bones, and cis-RA-associated premature closure of the lower-extremity growth plates, with significant reduction in adult stature. A better appreciation of the detrimental effect of cis-RA on the growing skeleton is needed to monitor at-risk patients and to provide timely interventions. © 2015 S. Karger AG, Basel.

  5. Short-term effects of teriparatide versus placebo on bone biomarkers, structure, and fracture healing in women with lower-extremity stress fractures: A pilot study.

    Science.gov (United States)

    Almirol, Ellen A; Chi, Lisa Y; Khurana, Bharti; Hurwitz, Shelley; Bluman, Eric M; Chiodo, Christopher; Matzkin, Elizabeth; Baima, Jennifer; LeBoff, Meryl S

    2016-09-01

    In this pilot, placebo-controlled study, we evaluated whether brief administration of teriparatide (TPTD) in premenopausal women with lower-extremity stress fractures would increase markers of bone formation in advance of bone resorption, improve bone structure, and hasten fracture healing according to magnetic resonance imaging (MRI). Premenopausal women with acute lower-extremity stress fractures were randomized to injection of TPTD 20-µg subcutaneous (s.c.) (n = 6) or placebo s.c. (n = 7) for 8 weeks. Biomarkers for bone formation N-terminal propeptide of type I procollagen (P1NP) and osteocalcin (OC) and resorption collagen type-1 cross-linked C-telopeptide (CTX) and collagen type 1 cross-linked N-telopeptide (NTX) were measured at baseline, 4 and 8 weeks. The area between the percent change of P1NP and CTX over study duration is defined as the anabolic window. To assess structural changes, peripheral quantitative computed topography (pQCT) was measured at baseline, 8 and 12 weeks at the unaffected tibia and distal radius. The MRI of the affected bone assessed stress fracture healing at baseline and 8 weeks. After 8 weeks of treatment, bone biomarkers P1NP and OC increased more in the TPTD- versus placebo-treated group (both p ≤ 0.01), resulting in a marked anabolic window (p ≤ 0.05). Results from pQCT demonstrated that TPTD-treated women showed a larger cortical area and thickness compared to placebo at the weight bearing tibial site, while placebo-treated women had a greater total tibia and cortical density. No changes at the radial sites were observed between groups. According to MRI, 83.3% of the TPTD- and 57.1% of the placebo-treated group had improved or healed stress fractures (p = 0.18). In this randomized, pilot study, brief administration of TPTD showed anabolic effects that TPTD may help hasten fracture healing in premenopausal women with lower-extremity stress fractures. Larger prospective studies are warranted to determine

  6. Mandelbrot's Extremism

    NARCIS (Netherlands)

    Beirlant, J.; Schoutens, W.; Segers, J.J.J.

    2004-01-01

    In the sixties Mandelbrot already showed that extreme price swings are more likely than some of us think or incorporate in our models.A modern toolbox for analyzing such rare events can be found in the field of extreme value theory.At the core of extreme value theory lies the modelling of maxima

  7. Influence of antithyroid medication on effective half-life and uptake of {sup 131} I following radioiodine therapy; Einflussfon thyreostatischer Medikation auf die effektive Halbwertzeit und den Uptake von {sup 131}Iod waehrend einer Radioiodtherapie

    Energy Technology Data Exchange (ETDEWEB)

    Moka, D. [Koeln Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Voth, E. [Koeln Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Schicha, H. [Koeln Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    1997-04-01

    Aim: A radioiodine therapy (RIT) in thyrotoxic patients receiving antithyroid drugs (ATD) leads in comparison to nonpretreated patients either to higher therapeutic doses or to higher treatment failure rates. Aim of this study was to optimize the effect of RIT in patients pretreated with ATD. Methods: Therefore, the influence of ATD was assessed in 109 patients with shortened effective half-life of {sup 131}I. RIT was performed under stationary conditions. Radioiodine activity of the thyroid gland was stopped three days after RIT. The patients antithyroid medication was stopped three days after RIT. The progress of the first RIT and of a second radioiodine application, which still was necessary in 29 patients, was compared to 32 patients receiving ATD, continuously. Results: Values of effective half-life for {sup 131}I rose significantly from 3.2{+-}0.2 to 5.7{+-}0.2 days (Graves` disease: 3.4 to 5.7 days; toxic goiters` disease: Multifocal autonomy 3.2 to 6.2 days; unifocal autonomy 2.5 auf 5.0 days) 2-3 days after stopping ATD. There was an increase of the {sup 131}I-uptake of a second RIT decreased significantly in patients receiving ATD, continuously. Conclusion: Effective half-life and uptake of {sup 131}I was affected significantly by ATD. The stop taking of ATD after RIT is useful to improve an apparent insufficient RIT in thyrotoxic patients receiving ATD. (orig.) [Deutsch] Ziel: Eine Radioiodtherapie (RITh) unter laufender thyreostatischer Medikation bei hyperthyreoten Patienten fuehrt im Vergleich zu unbehandelten Patienten entweder zu hoeheren Therapiedosen oder zu einem hoeheren Prozentsatz von Therapieversagern. Ziel dieser Studie war es, die RITh unter thyreostatischer Medikation zu optimieren. Methoden: Der Einfluss der thyreostatischen Medikation wurde bei 109 Patienten mit verkuerzter thyreoidaler Halbwertzeit von {sup 131}I untersucht. Bei 77 Patienten wurde die thyreostatische Medikation am 3. Tag nach RITh abgesetzt. Der Verlauf der RITh bzw

  8. Decay properties of short-lived mass-separated fission products

    International Nuclear Information System (INIS)

    Lund, E.

    1977-01-01

    The present work describes determinations of total β-decay energies and studies of delayed neutron emission including the identification and half-life determinations of delayed neutron precursors and the measurement of neutron spectra. It also includes a short review of the OSIRIS on-line isotope separator facility. (Auth.)

  9. Development of the k0-based cyclic neutron activation analysis for short-lived radionuclides

    NARCIS (Netherlands)

    Dung, H.M.; Blaauw, M.; Beasley, D.; Freitas, M.D.C.

    2011-01-01

    The k0-based cyclic neutron activation analysis (k0-CNAA) technique has been studied to explore the applicability at the Portuguese research reactor (RPI). In particular, for the determination of elements which form short-lived radionuclides, particularly fluorine (20F, 11.16 s half-life) and

  10. Short-term effects of extremely low-frequency pulsed electromagnetic field and pulsed low-level laser therapy on rabbit model of corneal alkali burn.

    Science.gov (United States)

    Rezaei Kanavi, Mozhgan; Tabeie, Faraj; Sahebjam, Farzin; Poursani, Nima; Jahanbakhsh, Nazanin; Paymanpour, Pouya; AfsarAski, Sasha

    2016-04-01

    This study was conducted to investigate the effect of combining extremely low frequency-pulsed electromagnetic field (ELF-PEMF) and low-level laser therapy (LLLT) on alkali-burned rabbit corneas. Fifty alkali-burned corneas of 50 rabbits were categorized into five groups: ELF-PEMF therapy with 2 mT intensity (ELF 2) for 2 h daily; LLLT for 30 min twice daily; combined ELF-PEMF and LLLT (ELF + LLLT); medical therapy (MT); and control (i.e., no treatment). Clinical examination and digital photography of the corneas were performed on days 0, 2, 7, and 14. After euthanizing the rabbits, the affected eyes were evaluated by histopathology. The clinical and histopathologic results were compared between the groups. On days 7 and 14, no significant difference in the corneal defect area was evident between the ELF, LLLT, ELF + LLLT, and MT groups. Excluding the controls, none of the study groups demonstrated a significant corneal neovascularization in both routine histopathology and immunohistochemistry for CD31. Keratocyte loss was significantly higher in the MT group than in the ELF, LLLT, and ELF + LLLT groups. Moderate to severe stromal inflammation in the LLLT group was comparable with that in the MT group and was significantly lower than that in the other groups. In conclusion, combining LLLT and ELF was not superior to ELF alone or LLLT alone in healing corneal alkali burns. However, given the lower intensity of corneal inflammation and the lower rate of keratocytes loss with LLLT, this treatment may be superior to other proposed treatment modalities for healing alkali-burned corneas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. An overview of the ecological half-life of the 137Cs radioisotope and a determination of radioactivity levels in sediment samples after Chernobyl in the Eastern Black Sea, Turkey

    Science.gov (United States)

    Baltas, Hasan; Sirin, Murat; Dalgic, Goktug; Cevik, Ugur

    2018-01-01

    A study which determined the activity concentration of 137Cs in sediments contaminated by effluents from the Chernobyl accident which had collected along the coast of the Eastern Black Sea region in Turkey was carried out in 1993. Marine sediment samples were collected in 2015 from the same fifteen sampling points, and the activity concentrations of 226Ra, 232Th, 40K and 137Cs were determined for the sediment samples. The activity concentrations ranged from 10.94-25.95, 12.14-33.05, 265.74-459.89 and 2.08-37.45 Bq kg- 1 for 226Ra, 232Th, 40K and 137Cs respectively. The results showed that there was a steep decline in 137Cs within the sediment at most of the sampling sites from the Eastern Black Sea region during the 22-year period, except for two sites at which the measured levels were much higher. This may be the result of the combined effects of radioactive contaminant entry into this area from rivers, environmental changes and nuclear testing between 1993 and 2015. Furthermore, the ecological half-life (EHL) of the 137Cs radionuclide was estimated for the sediment samples, and radiological hazard parameters such as the absorbed dose rate in air (D), the annual effective dose equivalent (AEDE) and the excess lifetime cancer risk (ELCR) were calculated and compared with the international recommended values. It was shown that these sediments do not present any significant health risk for humans in this area.

  12. Investigation of temperature effect on half-life periods of long-lived isomer sup 1 sup 8 sup 0 sup m Hf and sup 8 sup 7 sup m Sr

    CERN Document Server

    Alpatov, V G; Davydov, A V; Isaev, Y N; Kartashov, G R; Korotkov, M M; Samojlov, V M

    2001-01-01

    The experiments on measuring the half-life periods of the sup 1 sup 8 sup 0 sup m Hf and sup 8 sup 7 sup m Sr long-lived isomers at the room temperature and at 77 K with application of the HfO sub 2 , Sr(NO sub 3) sub 2 and SrCO sub 3 massive samples are described. The isomer states of the corresponding nuclei were formed by the samples irradiation through neutrons from the Pu-Be source. According to the Vysotski theory and other authors the surrounding of the gamma-active nuclei by a large number of the same nuclei in the basic state should lead to the T sub 1 sub / sub 2 growth due to distortion of the zero electromagnetic vacuum oscillations near the nuclear energy level value. Decrease in the sample temperature leads to the narrowing of the gamma-lines, especially for the Moessbauer low-energy transitions, which increases the resonance effect on the zero oscillations spectrum. Increase in the T sub 1 sub / sub 2 by 2.99 +- 0.87% was observed by cooling the sup 1 sup 8 sup 0 sup m Hf isomer sample, in the ...

  13. Landscape genetics reveals inbreeding and genetic bottlenecks in the extremely rare short-globose cacti Mammillaria pectinifera (Cactaceae as a result of habitat fragmentation

    Directory of Open Access Journals (Sweden)

    Reyna Maya-García

    2017-02-01

    Full Text Available Mammillaria pectinifera is an endemic, short-globose cactus species, included in the IUCN list as a threatened species with only 18 remaining populations in the Tehuacán-Cuicatlán Valley in central Mexico. We evaluated the population genetic diversity and structure, connectivity, recent bottlenecks and population size, using nuclear microsatellites. M. pectinifera showed high genetic diversity but some evidence of heterozygote deficiency (FIS, recent bottlenecks in some populations and reductions in population size. Also, we found low population genetic differentiation and high values of connectivity for M. pectinifera, as the result of historical events of gene flow through pollen and seed dispersal. M. pectinifera occurs in sites with some degree of disturbance leading to the isolation of its populations and decreasing the levels of gene flow among them. Excessive deforestation also changes the original vegetation damaging the natural habitats. This species will become extinct if it is not properly preserved. Furthermore, this species has some ecological features that make them more vulnerable to disturbance such as a very low growth rates and long life cycles. We suggest in situ conservation to prevent the decrease of population sizes and loss of genetic diversity in the natural protected areas such as the Tehuacán-Cuicatlán Biosphere Reserve. In addition, a long-term ex situ conservation program is need to construct seed banks, and optimize seed germination and plant establishment protocols that restore disturbed habitats. Furthermore, creating a supply of living plants for trade is critical to avoid further extraction of plants from nature.

  14. Activation analysis with neutron generators using short-lived radionuclides

    International Nuclear Information System (INIS)

    Salma, I.

    1993-01-01

    The short half-life involves a number of important differences in production, transportation and measurement of radionuclides, and in counting statistics as compared with those in traditional activation analysis. Experiments were performed to investigate the analytical possibilities and prospective utilization of short-lived radionuclides produced by 14-MeV neutron irradiation. A rapid pneumatic transfer system for use with neutron generators was installed and applied for detecting radionuclides with a half-life from 300 ms to 30 s. The transport time for samples with a total mass of 1-4 g is between 130 and 160 ms for pressurized air of 0.1-0.4 MPa. 11 elements were studied by the conventional activation method using both a typical pneumatic transport system (run time 3 s) and the fast pneumatic transport facility. The effect of the cyclic activation technique on the elemental sensitivities was also investigated. (orig.)

  15. Prediction of drug terminal half-life and terminal volume of distribution after intravenous dosing based on drug clearance, steady-state volume of distribution, and physiological parameters of the body.

    Science.gov (United States)

    Berezhkovskiy, Leonid M

    2013-02-01

    The steady state, V(ss), terminal volume of distribution, V(β), and the terminal half-life, t(1/2), are commonly obtained from the drug plasma concentration-time profile, C(p)(t), following intravenous dosing. Unlike V(ss) that can be calculated based on the physicochemical properties of drugs considering the equilibrium partitioning between plasma and organ tissues, t(1/2) and V(β) cannot be calculated that way because they depend on the rates of drug transfer between blood and tissues. Considering the physiological pharmacokinetic model pertinent to the terminal phase of drug elimination, a novel equation that calculates t(1/2) (and consequently V(β)) was derived. It turns out that V(ss), the total body clearance, Cl, equilibrium blood-plasma concentration ratio, r; and the physiological parameters of the body such as cardiac output, and blood and tissue volumes are sufficient for determination of terminal kinetics. Calculation of t(1/2) by the obtained equation appears to be in good agreement with the experimentally observed vales of this parameter in pharmacokinetic studies in rat, monkey, dog, and human. The equation for the determination of the pre-exponent of the terminal phase of C(p)(t) is also found. The obtained equation allows to predict t(1/2) in human assuming that V(ss) and Cl were either obtained by allometric scaling or, respectively, calculated in silico or based on in vitro drug stability measurements. For compounds that have high clearance, the derived equation may be applied to calculate r just using the routine data on Cl, V(ss), and t(1/2), rather than doing the in vitro assay to measure this parameter. Copyright © 2012 Wiley Periodicals, Inc.

  16. Direct measurement of the half-life of Rb{sup 87}; Mesure directe de la periode du rubidium-87; Pryamoe izmerenie poluraspada rubidiya-87; Medicion directa del periodo del {sup 87}Rb

    Energy Technology Data Exchange (ETDEWEB)

    McNair, A; Wilson, H W [United Kingdom Atomic Energy Authority, Aldermaston, Berks. (United Kingdom)

    1962-01-15

    The half-life of Rb{sup 87} has been measured directly by determining the specific activity by a counting method. The half-lives previously obtained lie in the range 4 - 6 x 10{sup 10} years, a value of 5 x 10{sup 10} years being taken usually. Direct counting is rather difficult because of the presence of a large number of very-low-energy electrons in the Rb{sup 87} spectrum. However, it is clearly very desirable to obtain a precise value by the counting method and this the authors have tried to do. In these measurements special attention must be paid to the reduction of thickness of source and of source backing. To increase the accuracy of the measurements, the following methods were used. The source thickness was reduced by use of (i) a 4-{pi} proportional counter of large source area (up to 100 cm{sup 2}), (ii) anti-coincidence operation to reduce background, and (iii) enriched Rb{sup 87} which permits a four-fold reduction in source thickness for a given activity. By these methods, sources down to 5 {mu}g/cm{sup 2} have been measured. Also the relationship between half-life and source thickness was examined so that correction could be made for the very small absorption which remained. The effect of source backing thickness is not so great and can be calculated from (i) the difference in count-rates on either side of the thin supports used and (ii) a study of dependence of half-life on source support thickness. These experiments give a value of about 5.25 x 10{sup 10} years for the half-life. (author) [French] On a mesure la periode du Tubidium-87 directement, en determinant l'activite specifique par comptage. Les periodes obtenues anterieurement se situent entre 4 et 6 {center_dot} 10{sup 10} ans; la valeur habituellement adoptee est de 5 {center_dot} 10{sup 10} ans. Le comptage direct est d'un emploi assez difficile par suite de la presence d'un grand nombre d'electrons de tres faible energie dans le spectre du rubidium-87. Il n'en serait pas moins tres utile

  17. Extreme cosmos

    CERN Document Server

    Gaensler, Bryan

    2011-01-01

    The universe is all about extremes. Space has a temperature 270°C below freezing. Stars die in catastrophic supernova explosions a billion times brighter than the Sun. A black hole can generate 10 million trillion volts of electricity. And hypergiants are stars 2 billion kilometres across, larger than the orbit of Jupiter. Extreme Cosmos provides a stunning new view of the way the Universe works, seen through the lens of extremes: the fastest, hottest, heaviest, brightest, oldest, densest and even the loudest. This is an astronomy book that not only offers amazing facts and figures but also re

  18. Half-Life Studies of Radiocaesium in Humans; Etudes sur la Periode de Radiocesium chez l'Homme; 0418 0421 0421 041b 0415 0414 ; Estudio sobre el Periodo Biologico del Radiocesio en el Hombre

    Energy Technology Data Exchange (ETDEWEB)

    Naversten, Y.; Liden, K. [Radiation Physics Department, University of Lund (Sweden)

    1964-11-15

    The retention of caesium-137 in humans has been studied in several cases. Two adult men were intravenously administered a small quantity of caesium-137. They were followed about 300 days by frequent whole-body counting and with excreta collection during the initial period. The retention decreased as a sum of two exponentials. The slowest compartment decreased with a half-life of about 75 d. One of them was also given caesium-137 orally 2 years later with the same excretion pattern obtained as after intravenous injection. The excretion rate of caesium-137 has also been studied in a different way for large groups of men, women and children through comparison with diet data. From a group of 10 people, voluntarily changing their diet, the average excretion rate could be calculated from whole-body counting at an interval of six weeks. The excretion also has been obtained from a study on two people after an oral administration of caesium-132. Detailed results on these studies will be given particularly with respect to the elimination rate of caesium, i.e. the biological half-life and its variation with sex and age. On the average, half-lives ranging from 30 to 90 d have been obtained. (author) [French] La retention de cesium 137 chez l'homme a ete etudiee sur plusieurs sujets. Ainsi, on a administre a deux hommes adultes, par voie intraveineuse, une petite quantite de cesium 137. On les a suivis pendant 300 j environ en faisant de frequents dosages de l'activite du corps et en recueillant les excreta au debut de la periode. La fonction qui representait la decroissance de la retention est une somme de deux exponentielles. La fraction qui decroissait le plus lentement avait une periode d'environ 75 j. Deux ans plus tard, on a administre du cesium 137 a un des deux sujets, par voie buccale, et on a obtenu le meme regime d'elimination qu'apres l'injection intraveineuse. On a aussi etudie le taux d'elimination de cesium 137 par une methode differente pour des groupes

  19. Short-lived non-coding transcripts (SLiTs): Clues to regulatory long non-coding RNA.

    Science.gov (United States)

    Tani, Hidenori

    2017-03-22

    Whole transcriptome analyses have revealed a large number of novel long non-coding RNAs (lncRNAs). Although the importance of lncRNAs has been documented in previous reports, the biological and physiological functions of lncRNAs remain largely unknown. The role of lncRNAs seems an elusive problem. Here, I propose a clue to the identification of regulatory lncRNAs. The key point is RNA half-life. RNAs with a long half-life (t 1/2 > 4 h) contain a significant proportion of ncRNAs, as well as mRNAs involved in housekeeping functions, whereas RNAs with a short half-life (t 1/2 regulatory ncRNAs and regulatory mRNAs. This novel class of ncRNAs with a short half-life can be categorized as Short-Lived non-coding Transcripts (SLiTs). I consider that SLiTs are likely to be rich in functionally uncharacterized regulatory RNAs. This review describes recent progress in research into SLiTs.

  20. Global predictability of temperature extremes

    Science.gov (United States)

    Coughlan de Perez, Erin; van Aalst, Maarten; Bischiniotis, Konstantinos; Mason, Simon; Nissan, Hannah; Pappenberger, Florian; Stephens, Elisabeth; Zsoter, Ervin; van den Hurk, Bart

    2018-05-01

    Extreme temperatures are one of the leading causes of death and disease in both developed and developing countries, and heat extremes are projected to rise in many regions. To reduce risk, heatwave plans and cold weather plans have been effectively implemented around the world. However, much of the world’s population is not yet protected by such systems, including many data-scarce but also highly vulnerable regions. In this study, we assess at a global level where such systems have the potential to be effective at reducing risk from temperature extremes, characterizing (1) long-term average occurrence of heatwaves and coldwaves, (2) seasonality of these extremes, and (3) short-term predictability of these extreme events three to ten days in advance. Using both the NOAA and ECMWF weather forecast models, we develop global maps indicating a first approximation of the locations that are likely to benefit from the development of seasonal preparedness plans and/or short-term early warning systems for extreme temperature. The extratropics generally show both short-term skill as well as strong seasonality; in the tropics, most locations do also demonstrate one or both. In fact, almost 5 billion people live in regions that have seasonality and predictability of heatwaves and/or coldwaves. Climate adaptation investments in these regions can take advantage of seasonality and predictability to reduce risks to vulnerable populations.

  1. Be-7 as a tracer for short-term soil surface changes - opportunities and limitations

    Science.gov (United States)

    Baumgart, Philipp

    2013-04-01

    Within the last 20 years the cosmogenic nuclide Beryllium-7 was successfully established as a suitable tracer element to detect soil surface changes with a high accuracy. Particularly soil erosion rates from single precipitation events are in the focus of different studies due to the short radioactive half-life of the Be-7 isotope. High sorption at topmost soil particles and immobility at given pH-values enable fine-scaled erosion modelling down to 2 mm increments. But some important challenging limitations require particular attention, starting from sampling up to the final data evaluation. E.g. these are the realisation of the fine increment soil collection, the limiting amount of measurable samples per campaign due to the short radioactive half-life and the specific requirements for the detector measurements. Both, the high potential and the challenging limitations are presented as well as future perspectives of that tracer method.

  2. Development and application of the generator for the short-living nuclides production

    International Nuclear Information System (INIS)

    Tsejner, A.

    1979-01-01

    The results are stated of investigations by means of radioisotopes on the substance transfer in technological equipment. For these purposes, in most cases, nuclides with high gamma-activity are used and, if possible, having short half-life because the short half-life gives certain advantages in the cases when it is impossible to store radioactive substances in the technological equipment for a long time. It is noted that in connection with short half-life of the nucludes used for labelling and for the economic and radiation safety reasons, activity of these nuclides can not be high. It has been established that the most suitable nuclide for the labelling purpose is lanthanum-140 produced either in a nuclear reactor, or by means of separation from barium=-140 transforming into lanthanum-140 in an isotopic generator. Some methods of lanthanum separation from barium are described, in particular, in the isotopic generator described, barium is adsorbed on the cation-exchanger KPS-200 having high enough stability with respect to the ionozing radiations. As an eluent the 10 -2 M solution of the complexone (Na 2 - EDTA) was used. The complexone solution can be easely obtained and, because of the hydrolysis, it serves as a buffer solution. The data are given for radiation purity and yield of lanthanum-=140 [ru

  3. Extremely Preterm Birth

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Extremely Preterm Birth Home For Patients Search FAQs Extremely Preterm Birth ... Spanish FAQ173, June 2016 PDF Format Extremely Preterm Birth Pregnancy When is a baby considered “preterm” or “ ...

  4. Angiography of the upper extremity

    International Nuclear Information System (INIS)

    Janevski, B.K.

    1982-01-01

    This thesis provides a description of the technical and medical aspects of arteriography of the upper extremity and an extensive analysis of the angiographic anatomy and pathology of 750 selective studies performed in more than 500 patients. A short historical review is provided of angiography as a whole and of arteriography of the hand in particular. The method of percutaneous transfemoral catheterization of the arteries of the upper extremity and particularly the arteries of the hand is considered, discussing the problems the angiographer encounters frequently, describing the angiographic complications which may occur and emphasizing the measures to keep them to a minimum. The use of vasodilators in hand angiography is discussed. A short description of the embryological patterns persisting in the arteries of the arm is included in order to understand the congenital variations of the arteries of the upper extremity. The angiographic patterns and clinical aspects of the most common pathological processes involving the arteries of the upper extremities are presented. Special attention is paid to the correlation between angiography and pathology. (Auth.)

  5. Rapid transfer of short-lived radioisotopes via a 2. 4 km rabbit system

    Energy Technology Data Exchange (ETDEWEB)

    Burgerjon, J J; Gelbart, Z; Lau, V; Lehnart, D; Lenz, J; Pate, B D; Ruth, T J; Sprenger, H P; van Oers, N S.C.

    1984-09-01

    A 2.4 km long pipeline between a cyclotron and a hospital is used for the rapid transfer of short-lived radiopharmaceuticals. The vials containing the pharmaceuticals are placed inside capsules (rabbits) that are blown through a tube by means of compressed air. Travel times as short as 2 min are achieved, which makes the system suitable for the transfer of /sup 15/O, which has a 2 min half-life. The construction and test results of the system are described along with a computer model, developed to explain some properties of the system. 7 references, 15 figures, 2 tables.

  6. Investigations into the transfer of 134+137cesium from Chernobyl fall-out-contaminated grasscobs in the bodies of fallow deer and angora rabbits and on the biological half-life of radio-cesium by means of whole-body gamma spectroscopy

    International Nuclear Information System (INIS)

    Feiden, F.

    1989-01-01

    The present work concerns a feeding experiment to establish the transfer-factors of 134+137 cesium from Chernobyl fall-out-contaminated grasscobs in the bodies of fallow deer (Dama-dama) and angora rabbits (Oryctolagus cuniculus). The transfer factor from the feed-stuff in the fallow deer body amounted to 0.0311 d/kg independent of the proportion of the contaminated grasscobs in the overall daily ration of food. The 137 Cs activity/kg in the flesh of two killed deer averaged about the factor 1.35, in the joint muscles about the factor 1.44 higher. An increase in the transfer factor for the fallow deers flesh to 0.0448 d/kg is assumed. The transfer factor (whole body) for the angora rabbits amounted to 0.285 d/kg. Two animals killed in balanced condition displayed around the factor 1.35 higher cesium values in the muscles. On this base the TF (meat) could be given as at 0.385 d/kg. The biological half-life of the radio-cesium in the body of fallow deer comprised a fast component of 0.3 d and a proportion of about 37% in overall activity and a slower one of 13 d with a 63% proportion. On an average it amounted to 8.3 d for excretion of the first half of the initial burden. At 5.5 d, a fallow deer burdened by only one i.v. injection excreted 50% of the initial activity markedly more quickly. Two proportionally equal phases of 1.2 and 10 days of biological half-time were recognised. As regards the angora rabbits, the biological half-life amounted to 1.2 d for the faster component, and for a slower one about 8 d. The first half of the initial activity was excreted after about 5.5 d. (orig./MG) [de

  7. Short wavelength FELS

    International Nuclear Information System (INIS)

    Sheffield, R.L.

    1991-01-01

    The generation of coherent ultraviolet and shorter wavelength light is presently limited to synchrotron sources. The recent progress in the development of brighter electron beams enables the use of much lower energy electron rf linacs to reach short-wavelengths than previously considered possible. This paper will summarize the present results obtained with synchrotron sources, review proposed short- wavelength FEL designs and then present a new design which is capable of over an order of magnitude higher power to the extreme ultraviolet. 17 refs., 10 figs

  8. Short wavelength FELS

    Energy Technology Data Exchange (ETDEWEB)

    Sheffield, R.L.

    1991-01-01

    The generation of coherent ultraviolet and shorter wavelength light is presently limited to synchrotron sources. The recent progress in the development of brighter electron beams enables the use of much lower energy electron rf linacs to reach short-wavelengths than previously considered possible. This paper will summarize the present results obtained with synchrotron sources, review proposed short- wavelength FEL designs and then present a new design which is capable of over an order of magnitude higher power to the extreme ultraviolet. 17 refs., 10 figs.

  9. Short philtrum

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003302.htm Short philtrum To use the sharing features on this page, please enable JavaScript. A short philtrum is a shorter than normal distance between ...

  10. Half Life - The divided life of Bruno Maximovitch Pontecorvo

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    When Bruno Pontecorvo fled to the USSR at the height of the Cold War in 1950, half way through his life, the British Government, MI5 and FBI tried to portray him as scientifically insignificant, and to imply that his disappearance posed no threat to the West. In reality Pontecorvo was already one of the leading experts in nuclear physics, and recently declassified papers reveal that a prime agenda of FBI and MI5 was to cover up their errors. . During his time in the USSR he made major contributions to physics, and justified the sobriquet: "Mr Neutrino". This talk will reveal the background to his sudden flight, and also evaluate his work in theoretical physics in the aftermath of his arrival in Dubna. Previously secret documents now show that he proposed the concept of associated production before Gell Mann and Pais, and he had an idea to discover the neutrino at a reactor. He may be considered the father of neutrino astronomy with his successful prediction that neutrinos from a supernova could be detected, b...

  11. Determination of half-life of Ks0

    International Nuclear Information System (INIS)

    Urrutia, Z.; Felix, J.

    1999-01-01

    In a K s 0 high statistics sample, created in pp reactions at 27.5 GeV, we determined K s 0 mean life to be (0.893 ± 0.006) x 10 -10 s. This result agrees, inside experimental errors, with the world wide accepted value. In this paper we describe the experimental details and the used technique to measure K s 0 mean life. (Author)

  12. What Is the Half-Life of Basketball Teams?

    Science.gov (United States)

    Hrepic, Zdeslav

    2013-01-01

    What do basketball teams have in common with radioactive nuclei? It turns out, there is more here than first meets the eye. The National Collegiate Athletic Association (NCAA) basketball tournaments feeds fans' craving when NBA competitions are not in swing, and the college tournament time has been referred to as "March Madness" or…

  13. Half-life Measurements of Levels in {sup 75}As

    Energy Technology Data Exchange (ETDEWEB)

    Hoejeberg, M; Malmskog, S G

    1969-04-15

    Half-lives for three levels in {sup 75}As have been determined using an electron-electron coincidence spectrometer. The following results have been obtained. T{sub 1/2} (199 keV) = 0.87 {+-} 0.03 nsec, T{sub 1/2} (280 keV) = 0.28 {+-} 0.02 nsec and T{sub 1/2} (401 keV) = 1. 67 {+-} 0.14 nsec.

  14. Half-Life Measurements in {sup 134}l

    Energy Technology Data Exchange (ETDEWEB)

    Berg, V; Hoeglund, Aa

    1970-07-01

    Properties of levels in I following the decay of {sup 13T}e have been investigated using a Ge(Li) detector and a double lens coincidence spectrometer. 4 new transitions were found. Half-lives of the lowest excited levels were measured with the following results: T{sub 1/2} (79.5 keV) = 1.62 {+-} 10 ns; T{sub 1/2} (181.1 keV) < 100 ps; T{sub 1/2} (210.8 keV) < 150 ps.

  15. Injuries in an Extreme Conditioning Program

    OpenAIRE

    Aune, Kyle T.; Powers, Joseph M.

    2016-01-01

    Background: Extreme conditioning programs (ECPs) are fitness training regimens relying on aerobic, plyometric, and resistance training exercises, often with high levels of intensity for a short duration of time. These programs have grown rapidly in popularity in recent years, but science describing the safety profile of these programs is lacking. Hypothesis: The rate of injury in the extreme conditioning program is greater than the injury rate of weightlifting and the majority of injuries occ...

  16. Extreme environment electronics

    CERN Document Server

    Cressler, John D

    2012-01-01

    Unfriendly to conventional electronic devices, circuits, and systems, extreme environments represent a serious challenge to designers and mission architects. The first truly comprehensive guide to this specialized field, Extreme Environment Electronics explains the essential aspects of designing and using devices, circuits, and electronic systems intended to operate in extreme environments, including across wide temperature ranges and in radiation-intense scenarios such as space. The Definitive Guide to Extreme Environment Electronics Featuring contributions by some of the world's foremost exp

  17. Extreme value distributions

    CERN Document Server

    Ahsanullah, Mohammad

    2016-01-01

    The aim of the book is to give a through account of the basic theory of extreme value distributions. The book cover a wide range of materials available to date. The central ideas and results of extreme value distributions are presented. The book rwill be useful o applied statisticians as well statisticians interrested to work in the area of extreme value distributions.vmonograph presents the central ideas and results of extreme value distributions.The monograph gives self-contained of theory and applications of extreme value distributions.

  18. Neuroimaging results, short-term assessment of psychomotor development and the risk of autism spectrum disorder in extremely premature infants (≤28 GA) - a prospective cohort study (preliminary report).

    Science.gov (United States)

    Rutkowska, Magdalena; Bekiesińska-Figatowska, Monika; Kmita, Grażyna; Terczyńska, Iwona; Polak, Katarzyna; Kalisiak, Marcin; Prażmowska, Dorota; Kiepura, Eliza; Szkudlińska-Pawlak, Sylwia; Seroczyńska, Małgorzata; Helwich, Ewa

    2018-01-01

    cerebellum in this group. In the remaining 5 children (42#37;) psychomotor development was rated as delayed. All of them had cerebellar haemorrhage. An increased risk of ASD was observed in 4 children who developed cerebellar hemorrhage. Conclusions: 1. The use of MRI at a term-equivalent age may contribute to the prognosis of neurodevelopmental outcomes in extremely premature infants, allowing risk stratification and thus enhancing early monitoring of a child's development and functional status 2. There is a clear tendency towards abnormal psychomotor development and positive screening for ASD to co-occur with abnormal MRI findings in the cerebellum.

  19. Applications of short lived nuclides in activation analysis, problems and progress

    Energy Technology Data Exchange (ETDEWEB)

    Grass, F [Atominstitut, Vienna (Austria)

    1976-07-01

    Short lived nuclides or isomeric transitions, respectively would have some advantages over long lived ones. Although we published a paper concerning a germanium-determination in iron meteorites some years ago, only few laboratories use this technique, the main reason being that the high matrix activity disturbs the measurement of energy-spectra. A multichannel analyzer in the time sequence mode enables Li-8 determination by a purely instrumental method which is therefore used more frequently. In the time sequence mode much higher counting rates up to 10 - 50 MHz are processed then by taking energy-spectra. This is the reason why activation analysis with short lived isomeric states is seldom applied when counting rate and pulse height are to be detected simultaneously. Exceptional difficulties are encountered in measurement of samples activated by a reactor pulse. Further difficulties arise from the fact that an optimal expelling time depends on the half life of the nuclide, and is more critical if the half life is short and the full width half maximum of the reactor pulse is small. Commercial Ge-Li-detectors can be used only at low counting rates, so that samples with high matrix activities cannot be measured. Modifying the electronic system enables registration of samples with high matrix activities. For short lived nuclides emitting hard beta-rays, e.g. B-12 or Li-8, a Cerenkov-detector is optimal. These problems are discussed in examples. (author)

  20. Systematic measurement of beta-decay half-lives of short-lived isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, T.; Yamamoto, H.; Kawade, K. [Nagoya Univ. (Japan); Iida, T.; Takahashi, A.; Kasugai, Y.; Ikeda, Y.

    1997-03-01

    We have measured the half-lives of short-lived isotopes for past decade and deduced the half-lives of 6 isotopes further. These results demonstrated that most of the literature values shorter than 10 min systematically deviated from our measurement ones. The cause seems to be that a large number of the previous half-life studies were performed with scintillation counters before 1970 and they had a difficulty in distinguishing the interest {gamma}-ray from the contamination and correcting for pile-up and dead-time losses. Moreover, the deviated data found to be quoted for evaluation. (author)

  1. Short communication

    African Journals Online (AJOL)

    abp

    2017-09-04

    Sep 4, 2017 ... Face-to-face interviews were conducted using a standardized ... Short communication. Open Access ... clinic during the time of the study and were invited to participate in the study. .... consume them. This is another ...

  2. SHORT COMMUNICATION

    African Journals Online (AJOL)

    PROF P.T. KAYE

    . SHORT COMMUNICATION. Formation and Structural Analysis of Novel Dibornyl Ethers. Perry T. Kaye*, Andrew R. Duggan, Joseph M. Matjila, Warner E. Molema, and. Swarnam S. Ravindran. Department of Chemistry, Rhodes University, Grahamstown, ...

  3. How extreme is extreme hourly precipitation?

    Science.gov (United States)

    Papalexiou, Simon Michael; Dialynas, Yannis G.; Pappas, Christoforos

    2016-04-01

    The importance of accurate representation of precipitation at fine time scales (e.g., hourly), directly associated with flash flood events, is crucial in hydrological design and prediction. The upper part of a probability distribution, known as the distribution tail, determines the behavior of extreme events. In general, and loosely speaking, tails can be categorized in two families: the subexponential and the hyperexponential family, with the first generating more intense and more frequent extremes compared to the latter. In past studies, the focus has been mainly on daily precipitation, with the Gamma distribution being the most popular model. Here, we investigate the behaviour of tails of hourly precipitation by comparing the upper part of empirical distributions of thousands of records with three general types of tails corresponding to the Pareto, Lognormal, and Weibull distributions. Specifically, we use thousands of hourly rainfall records from all over the USA. The analysis indicates that heavier-tailed distributions describe better the observed hourly rainfall extremes in comparison to lighter tails. Traditional representations of the marginal distribution of hourly rainfall may significantly deviate from observed behaviours of extremes, with direct implications on hydroclimatic variables modelling and engineering design.

  4. Optimization with Extremal Dynamics

    International Nuclear Information System (INIS)

    Boettcher, Stefan; Percus, Allon G.

    2001-01-01

    We explore a new general-purpose heuristic for finding high-quality solutions to hard discrete optimization problems. The method, called extremal optimization, is inspired by self-organized criticality, a concept introduced to describe emergent complexity in physical systems. Extremal optimization successively updates extremely undesirable variables of a single suboptimal solution, assigning them new, random values. Large fluctuations ensue, efficiently exploring many local optima. We use extremal optimization to elucidate the phase transition in the 3-coloring problem, and we provide independent confirmation of previously reported extrapolations for the ground-state energy of ±J spin glasses in d=3 and 4

  5. Classifying Returns as Extreme

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    2014-01-01

    I consider extreme returns for the stock and bond markets of 14 EU countries using two classification schemes: One, the univariate classification scheme from the previous literature that classifies extreme returns for each market separately, and two, a novel multivariate classification scheme tha...

  6. Short Stature

    DEFF Research Database (Denmark)

    Christesen, Henrik Boye Thybo; Pedersen, Birgitte Tønnes; Pournara, Effie

    2016-01-01

    -scale, non-interventional, multinational study. The patient cohort consisted of 5996 short pediatric patients diagnosed with growth hormone deficiency (GHD), Turner syndrome (TS) or born small for gestational age (SGA). The proportions of children with baseline height standard deviation score (SDS) below......The use of appropriate growth standards/references is of significant clinical importance in assessing the height of children with short stature as it may determine eligibility for appropriate therapy. The aim of this study was to determine the impact of using World Health Organization (WHO) instead...... of national growth standards/references on height assessment in short children. Data were collected from routine clinical practice (1998-2014) from nine European countries that have available national growth references and were enrolled in NordiNet® International Outcome Study (IOS) (NCT00960128), a large...

  7. Short Review

    DEFF Research Database (Denmark)

    Lynnerup, Niels; Rühli, Frank

    2015-01-01

    modality in ancient mummy research. The aim of this short review is to address the advantages and pitfalls of this particular technique for such unique samples. We recommend that when results of X-ray examination of mummies are presented, the specific recording data should be listed, and any given finds...

  8. Short fusion

    CERN Multimedia

    2002-01-01

    French and UK researchers are perfecting a particle accelerator technique that could aid the quest for fusion energy or make X-rays that are safer and produce higher-resolution images. Led by Dr Victor Malka from the Ecole Nationale Superieure des Techniques Avancees in Paris, the team has developed a better way of accelerating electrons over short distances (1 page).

  9. Short communication

    African Journals Online (AJOL)

    UPuser

    Short communication. Polymorphisms of the CAST gene in the Meishan and five other pig populations in China. Q.S. Wang. 1. , Y.C. Pan. 1#. , L.B. Sun. 2 and H. Meng. 1. 1 Department of Animal Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai. 201101, P.R. China. 2 Shanghai Institute of ...

  10. SHORT COMMUNICATION

    African Journals Online (AJOL)

    a

    ______. *Corresponding author. E-mail: vani_chem@yahoo.com. SHORT COMMUNICATION. OXIDATION OF L-CYSTINE BY CHROMIUM(VI) - A KINETIC STUDY. Kalyan Kumar Adari, Annapurna Nowduri and Vani Parvataneni*. Department of Inorganic and Analytical Chemistry, School of Chemistry, Andhra University,.

  11. Short communication

    NARCIS (Netherlands)

    Pantophlet, Andre J.; Gilbert, M.S.; Gerrits, W.J.J.; Vonk, R.J.

    2017-01-01

    Heavy veal calves (4-6 mo old) often develop problems with insulin sensitivity. This could lead to metabolic disorders and impaired animal growth performance. Studies in various animal species have shown that the supplementation of short-chain fructo-oligosaccharides (scFOS) can improve insulin

  12. Extremal surface barriers

    International Nuclear Information System (INIS)

    Engelhardt, Netta; Wall, Aron C.

    2014-01-01

    We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy

  13. Statistics of Extremes

    KAUST Repository

    Davison, Anthony C.; Huser, Raphaë l

    2015-01-01

    Statistics of extremes concerns inference for rare events. Often the events have never yet been observed, and their probabilities must therefore be estimated by extrapolation of tail models fitted to available data. Because data concerning the event

  14. Analysis of extreme events

    CSIR Research Space (South Africa)

    Khuluse, S

    2009-04-01

    Full Text Available ) determination of the distribution of the damage and (iii) preparation of products that enable prediction of future risk events. The methodology provided by extreme value theory can also be a powerful tool in risk analysis...

  15. Acute lower extremity ischaemia

    African Journals Online (AJOL)

    Acute lower extremity ischaemia. Acute lower limb ischaemia is a surgical emergency. ... is ~1.5 cases per 10 000 persons per year. Acute ischaemia ... Table 2. Clinical features discriminating embolic from thrombotic ALEXI. Clinical features.

  16. A robust combination approach for short-term wind speed forecasting and analysis – Combination of the ARIMA (Autoregressive Integrated Moving Average), ELM (Extreme Learning Machine), SVM (Support Vector Machine) and LSSVM (Least Square SVM) forecasts using a GPR (Gaussian Process Regression) model

    International Nuclear Information System (INIS)

    Wang, Jianzhou; Hu, Jianming

    2015-01-01

    With the increasing importance of wind power as a component of power systems, the problems induced by the stochastic and intermittent nature of wind speed have compelled system operators and researchers to search for more reliable techniques to forecast wind speed. This paper proposes a combination model for probabilistic short-term wind speed forecasting. In this proposed hybrid approach, EWT (Empirical Wavelet Transform) is employed to extract meaningful information from a wind speed series by designing an appropriate wavelet filter bank. The GPR (Gaussian Process Regression) model is utilized to combine independent forecasts generated by various forecasting engines (ARIMA (Autoregressive Integrated Moving Average), ELM (Extreme Learning Machine), SVM (Support Vector Machine) and LSSVM (Least Square SVM)) in a nonlinear way rather than the commonly used linear way. The proposed approach provides more probabilistic information for wind speed predictions besides improving the forecasting accuracy for single-value predictions. The effectiveness of the proposed approach is demonstrated with wind speed data from two wind farms in China. The results indicate that the individual forecasting engines do not consistently forecast short-term wind speed for the two sites, and the proposed combination method can generate a more reliable and accurate forecast. - Highlights: • The proposed approach can make probabilistic modeling for wind speed series. • The proposed approach adapts to the time-varying characteristic of the wind speed. • The hybrid approach can extract the meaningful components from the wind speed series. • The proposed method can generate adaptive, reliable and more accurate forecasting results. • The proposed model combines four independent forecasting engines in a nonlinear way.

  17. Short Communication

    African Journals Online (AJOL)

    huis

    Short Communication. QTL analysis of production traits on SSC3 in a Large White×Meishan pig resource family. B. Zuo. 1. , Y.Z. Xiong. 1#. , Y.H. Su. 2. , C.Y. Deng. 1. , M.G. Lei. 1. , F.E. Li. 1. , R. Zheng. 1 and S.W. Jiang. 1. 1 Key Laboratory of Swine Genetics and Breeding, Ministry of Agriculture & Key Lab of Agricultural ...

  18. Short-Selling, Leverage and Systemic Risk

    OpenAIRE

    Pais, Amelia; Stork, Philip A.

    2013-01-01

    During the Global Financial Crisis, regulators imposed short-selling bans to protect financial institutions. The rationale behind the bans was that “bear raids”, driven by short-sellers, would increase the individual and systemic risk of financial institutions, especially for institutions with high leverage. This study uses Extreme Value Theory to estimate the effect of short-selling on financial institutions’ individual and systemic risks in France, Italy and Spain; it also analyses the rela...

  19. Extreme Programming: Maestro Style

    Science.gov (United States)

    Norris, Jeffrey; Fox, Jason; Rabe, Kenneth; Shu, I-Hsiang; Powell, Mark

    2009-01-01

    "Extreme Programming: Maestro Style" is the name of a computer programming methodology that has evolved as a custom version of a methodology, called extreme programming that has been practiced in the software industry since the late 1990s. The name of this version reflects its origin in the work of the Maestro team at NASA's Jet Propulsion Laboratory that develops software for Mars exploration missions. Extreme programming is oriented toward agile development of software resting on values of simplicity, communication, testing, and aggressiveness. Extreme programming involves use of methods of rapidly building and disseminating institutional knowledge among members of a computer-programming team to give all the members a shared view that matches the view of the customers for whom the software system is to be developed. Extreme programming includes frequent planning by programmers in collaboration with customers, continually examining and rewriting code in striving for the simplest workable software designs, a system metaphor (basically, an abstraction of the system that provides easy-to-remember software-naming conventions and insight into the architecture of the system), programmers working in pairs, adherence to a set of coding standards, collaboration of customers and programmers, frequent verbal communication, frequent releases of software in small increments of development, repeated testing of the developmental software by both programmers and customers, and continuous interaction between the team and the customers. The environment in which the Maestro team works requires the team to quickly adapt to changing needs of its customers. In addition, the team cannot afford to accept unnecessary development risk. Extreme programming enables the Maestro team to remain agile and provide high-quality software and service to its customers. However, several factors in the Maestro environment have made it necessary to modify some of the conventional extreme

  20. Extreme meteorological conditions

    International Nuclear Information System (INIS)

    Altinger de Schwarzkopf, M.L.

    1983-01-01

    Different meteorological variables which may reach significant extreme values, such as the windspeed and, in particular, its occurrence through tornadoes and hurricanes that necesarily incide and wich must be taken into account at the time of nuclear power plants' installation, are analyzed. For this kind of study, it is necessary to determine the basic phenomenum of design. Two criteria are applied to define the basic values of design for extreme meteorological variables. The first one determines the expected extreme value: it is obtained from analyzing the recurence of the phenomenum in a convened period of time, wich may be generally of 50 years. The second one determines the extreme value of low probability, taking into account the nuclear power plant's operating life -f.ex. 25 years- and considering, during said lapse, the occurrence probabilities of extreme meteorological phenomena. The values may be determined either by the deterministic method, which is based on the acknowledgement of the fundamental physical characteristics of the phenomena or by the probabilistic method, that aims to the analysis of historical statistical data. Brief comments are made on the subject in relation to the Argentine Republic area. (R.J.S.) [es

  1. Acclimatization to extreme heat

    Science.gov (United States)

    Warner, M. E.; Ganguly, A. R.; Bhatia, U.

    2017-12-01

    Heat extremes throughout the globe, as well as in the United States, are expected to increase. These heat extremes have been shown to impact human health, resulting in some of the highest levels of lives lost as compared with similar natural disasters. But in order to inform decision makers and best understand future mortality and morbidity, adaptation and mitigation must be considered. Defined as the ability for individuals or society to change behavior and/or adapt physiologically, acclimatization encompasses the gradual adaptation that occurs over time. Therefore, this research aims to account for acclimatization to extreme heat by using a hybrid methodology that incorporates future air conditioning use and installation patterns with future temperature-related time series data. While previous studies have not accounted for energy usage patterns and market saturation scenarios, we integrate such factors to compare the impact of air conditioning as a tool for acclimatization, with a particular emphasis on mortality within vulnerable communities.

  2. Extremely deformable structures

    CERN Document Server

    2015-01-01

    Recently, a new research stimulus has derived from the observation that soft structures, such as biological systems, but also rubber and gel, may work in a post critical regime, where elastic elements are subject to extreme deformations, though still exhibiting excellent mechanical performances. This is the realm of ‘extreme mechanics’, to which this book is addressed. The possibility of exploiting highly deformable structures opens new and unexpected technological possibilities. In particular, the challenge is the design of deformable and bi-stable mechanisms which can reach superior mechanical performances and can have a strong impact on several high-tech applications, including stretchable electronics, nanotube serpentines, deployable structures for aerospace engineering, cable deployment in the ocean, but also sensors and flexible actuators and vibration absorbers. Readers are introduced to a variety of interrelated topics involving the mechanics of extremely deformable structures, with emphasis on ...

  3. Statistics of Extremes

    KAUST Repository

    Davison, Anthony C.

    2015-04-10

    Statistics of extremes concerns inference for rare events. Often the events have never yet been observed, and their probabilities must therefore be estimated by extrapolation of tail models fitted to available data. Because data concerning the event of interest may be very limited, efficient methods of inference play an important role. This article reviews this domain, emphasizing current research topics. We first sketch the classical theory of extremes for maxima and threshold exceedances of stationary series. We then review multivariate theory, distinguishing asymptotic independence and dependence models, followed by a description of models for spatial and spatiotemporal extreme events. Finally, we discuss inference and describe two applications. Animations illustrate some of the main ideas. © 2015 by Annual Reviews. All rights reserved.

  4. Meia-vida do ametryn em argissolo vermelho-amarelo e latossolo vermelho-amarelo, com diferentes valores de pH Determination of half-life of ametryn on red-yellow latosol and red-yellow ultisol with different pH values

    Directory of Open Access Journals (Sweden)

    S.R.B. Andrade

    2010-06-01

    Full Text Available Objetivou-se com este trabalho determinar a meia-vida (t½ do herbicida ametryn em Argissolo Vermelho-Amarelo e Latossolo Vermelho-Amarelo, com diferentes valores de pH. Foram utilizados vasos revestidos internamente com filme plástico e preenchidos com 330,0 g de amostras dos solos em estudo (Latossolo Vermelho-Amarelo - LVA com valores de pH corrigidos para 4,4, 4,9 e 5,8, e Argissolo Vermelho-Amarelo - PVA com pH 5,9. As amostras desses solos foram coletadas em pastagens degradadas isentas da aplicação de herbicidas. A essas amostras foi aplicado o ametryn na dose de 2,5 L ha-1. Doze horas após essa aplicação, foram retiradas as primeiras amostras de solo dos vasos, para determinação da concentração no tempo zero, e a cada cinco dias foram retiradas novas amostras de outros vasos, visando à determinação da concentração de ametryn ao longo do tempo. A extração do ametryn da matriz solo foi realizada por Extração Sólido Líquido com Partição em Baixa Temperatura (ESL-PBT, e o herbicida, quantificado por cromatografia líquida de alta eficiência - CLAE. Foi realizado, em paralelo, um teste biológico para determinação indireta da persistência do herbicida. A análise dos dados indicou que a meia-vida (t½ do ametryn nos solos avaliados foi de 26, 19, 12 e 11 dias para os solos LVA pH 4,4; LVA pH 4,9; LVA pH 5,8; e PVA pH 5,9, respectivamente. Ambos os métodos (cromatografia ou bioensaios utilizados para avaliação da persistência do ametryn nos solos evidenciaram que a degradação desse herbicida é muito influenciada pelo pH do solo e pelo teor de matéria orgânica.The objective of this study was to determine the half-life (t½ for the herbicide ametryn in Red-Yellow Latosol (LVA and Red-Yellow Ultisol (PVA with different pH values. Thus, plastic pots coated inside with plastic film were filled with 330 g of samples from the soils under study (LVA with pH values adjusted to 4.4, 4.9 and 5.8, and PVA pH 5

  5. Adventure and Extreme Sports.

    Science.gov (United States)

    Gomez, Andrew Thomas; Rao, Ashwin

    2016-03-01

    Adventure and extreme sports often involve unpredictable and inhospitable environments, high velocities, and stunts. These activities vary widely and include sports like BASE jumping, snowboarding, kayaking, and surfing. Increasing interest and participation in adventure and extreme sports warrants understanding by clinicians to facilitate prevention, identification, and treatment of injuries unique to each sport. This article covers alpine skiing and snowboarding, skateboarding, surfing, bungee jumping, BASE jumping, and whitewater sports with emphasis on epidemiology, demographics, general injury mechanisms, specific injuries, chronic injuries, fatality data, and prevention. Overall, most injuries are related to overuse, trauma, and environmental or microbial exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Extremal graph theory

    CERN Document Server

    Bollobas, Bela

    2004-01-01

    The ever-expanding field of extremal graph theory encompasses a diverse array of problem-solving methods, including applications to economics, computer science, and optimization theory. This volume, based on a series of lectures delivered to graduate students at the University of Cambridge, presents a concise yet comprehensive treatment of extremal graph theory.Unlike most graph theory treatises, this text features complete proofs for almost all of its results. Further insights into theory are provided by the numerous exercises of varying degrees of difficulty that accompany each chapter. A

  7. Studies on the separation of rare earth elements and the nuclear decay properties of short lived rare-earth nuclides in U-235 fission products

    International Nuclear Information System (INIS)

    Ohyoshi, Akira; Ohyoshi, Emiko.

    1980-01-01

    The effect of a complex-forming agent, with which rare earths consecutively form the complexes, on the separation of a pair of adjacent rare earths by electromigration has been investigated. The relation between the separation factor for two complexes and the ligand-ion concentration was examined in the separation of La-Ce and Ce-Pr pairs with nitrilotriacetic acid. Rare earths were able to be isolated rapidly at the optimum ligand-ion concentration in lower one, and this method was applied to study the nuclear decay properties of the short lived isotopes of La, Ce, Pr, Nd and Yt formed in the fission of U-235. This method permits the direct measurement of the decay of La-144 without the interference from the radiation of other fission products. The gamma-ray spectrum of La-144 was measured with a high resolution Ge(Li) detector, and the gamma-transition was observed. From the decay plots of two strong photopeaks, the half-life of La-144 was determined. In the case of Ce fraction, the photopeaks assigned to respective isotopes were observed. In the studies on the decay properties of Pr-148 and Pr-149, the decay plot of the strong photopeak showed good linearity, and the accurate half-life of Pr-148 was determined. Similarly, the half-life of Pr-149 was longer than the previously reported value. (Kako, I.)

  8. Stellar extreme ultraviolet astronomy

    International Nuclear Information System (INIS)

    Cash, W.C. Jr.

    1978-01-01

    The design, calibration, and launch of a rocket-borne imaging telescope for extreme ultraviolet astronomy are described. The telescope, which employed diamond-turned grazing incidence optics and a ranicon detector, was launched November 19, 1976, from the White Sands Missile Range. The telescope performed well and returned data on several potential stellar sources of extreme ultraviolet radiation. Upper limits ten to twenty times more sensitive than previously available were obtained for the extreme ultraviolet flux from the white dwarf Sirius B. These limits fall a factor of seven below the flux predicted for the star and demonstrate that the temperature of Sirius B is not 32,000 K as previously measured, but is below 30,000 K. The new upper limits also rule out the photosphere of the white dwarf as the source of the recently reported soft x-rays from Sirius. Two other white dwarf stars, Feige 24 and G191-B2B, were observed. Upper limits on the flux at 300 A were interpreted as lower limits on the interstellar hydrogen column densities to these stars. The lower limits indicate interstellar hydrogen densitites of greater than .02 cm -3 . Four nearby stars (Sirius, Procyon, Capella, and Mirzam) were observed in a search for intense low temperature coronae or extended chromospheres. No extreme ultraviolet radiation from these stars was detected, and upper limits to their coronal emisson measures are derived

  9. Extremity x-ray

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003461.htm Extremity x-ray To use the sharing features on this page, ... in the body Risks There is low-level radiation exposure. X-rays are monitored and regulated to provide the ...

  10. Extremity perfusion for sarcoma

    NARCIS (Netherlands)

    Hoekstra, Harald Joan

    2008-01-01

    For more than 50 years, the technique of extremity perfusion has been explored in the limb salvage treatment of local, recurrent, and multifocal sarcomas. The "discovery" of tumor necrosis factor-or. in combination with melphalan was a real breakthrough in the treatment of primarily irresectable

  11. Statistics of Local Extremes

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Bierbooms, W.; Hansen, Kurt Schaldemose

    2003-01-01

    . A theoretical expression for the probability density function associated with local extremes of a stochasticprocess is presented. The expression is basically based on the lower four statistical moments and a bandwidth parameter. The theoretical expression is subsequently verified by comparison with simulated...

  12. Use of short-lived radionuclides in the agricultural and environmental sciences

    International Nuclear Information System (INIS)

    Krohn, K.A.

    1985-01-01

    In addition to their well-known uses in physiology, biochemistry, and medicine, short-lived radioisotopes have played an important part in promoting the authors knowledge of the agricultural and environmental sciences. Numerous investigators have found that the scientific rewards justify the additional demands associated with use of short-lived radioisotopes when novel or uniquely precise results can be achieved. This is best exemplified by examining the use of 13 N. Nitrogen-13 is the longest lived radioisotope of this very important element. The 10-min half-life of 13 N has required that the agricultural or environmental test model be brought to the laboratory where the isotope is made, but this has been done successfully in numerous instances. One major incentive for this research has probably been the fact that there is no analog of the very useful 14 C tracer to study nitrogen chemistry and biology

  13. Extremes in nature

    CERN Document Server

    Salvadori, Gianfausto; Kottegoda, Nathabandu T

    2007-01-01

    This book is about the theoretical and practical aspects of the statistics of Extreme Events in Nature. Most importantly, this is the first text in which Copulas are introduced and used in Geophysics. Several topics are fully original, and show how standard models and calculations can be improved by exploiting the opportunities offered by Copulas. In addition, new quantities useful for design and risk assessment are introduced.

  14. Rhabdomyosarcoma of the extremity

    International Nuclear Information System (INIS)

    Rao, Bhaskar N

    1997-01-01

    Rhabdomyosarcoma is the most common soft tissue sarcoma accounting for almost 55%. These tumors arise from unsegmented mesoderm or primitive mesenchyma, which have the capacity to differentiate into muscle. Less than 5% occur in the first year of life. Extremity rhabdomyosarcoma are mainly seen in the adolescent years. The most common histologic subtype is the alveolar variant. Other characteristics of extremity rhabdomyosarcoma include a predilection for lymph node metastasis, a high local failure, and a relatively low survival rate. They often present as slow painless masses; however, lesions in the hand and foot often present as painful masses and imaging studies may show invasion of the bone. Initial diagnostic approaches include needle biopsy or incisional biopsy for larger lesions. Excisional biopsy is indicated preferably for lesions less than 2.5 cm. following this in most instances therapy is initiated with multi agent chemotherapy depending upon response, the next modality may be either surgery with intent to cure or radiation therapy. Amputation of an extremity for local control is not considered in most instances. Prognostic factors that have been determined over the years to be of significance by multi variant analysis have included age, tumor size, invasiveness, presence of either nodal or distant metastasis, and complete excision whenever feasible, with supplemental radiation therapy for local control

  15. Superconducting cyclotron magnet coil short

    International Nuclear Information System (INIS)

    Mallory, M.L.; Blosser, H.G.; Clark, D.J.; Launer, H.; Lawton, D.; Miller, P.; Resmini, F.

    1982-01-01

    In February 1981, a short circuit appeared in the superconducting coil of the K500 cyclotron. The short is resistive in character and therefore has no effect on steady state operation of the magnet. The resistance of the short varies, sometimes being below threshold of detection as a heat load on the cooling system and sometimes being significant. The resistance under certain conditions shows approximately cyclic phenomena with time constants in the range of seconds and other approximately cyclic phenomena which correlate with gross operating parameters of the magnet (shifting current from one coil to another at high field and lowering and raising the liquid helium level). A number of diagnostic studies of the short have been made, using 1) an array of flux sensing loops to sense the magnetic effect of the short, 2) voltage comparisons between upper and lower sections of the coil, 3) comparisons of forces in the nine member coil support system and 4) the effect of the short on the thermal charactersitics of the coil. Insulation failure or a metal chip shorting out turns have been explored in some detail but a convincing determination of the exact cause of the short may never be available, (even the extreme step of unwinding the coil having a significant probability that an imperfection with the observed characteristics would pass unnoticed). Analysis of the characteristics of the short indicated that the most serious consequence would be failure of the coils mechanical support system in the event that the magnet was quickly discharged, as in a dump or quench. To deal with this hazard, the support system has been modified by installing solid supports which prevent the coil from moving by an amount sufficient to damage the support system. We have also reexamined the data and calculations used in the original coil design and have made some additional measurements of the properties of the materials (yield strength, friction coefficient, Young's modulus) used in the

  16. Options with Extreme Strikes

    Directory of Open Access Journals (Sweden)

    Lingjiong Zhu

    2015-07-01

    Full Text Available In this short paper, we study the asymptotics for the price of call options for very large strikes and put options for very small strikes. The stock price is assumed to follow the Black–Scholes models. We analyze European, Asian, American, Parisian and perpetual options and conclude that the tail asymptotics for these option types fall into four scenarios.

  17. Opacity calculations for extreme physical systems: code RACHEL

    Science.gov (United States)

    Drska, Ladislav; Sinor, Milan

    1996-08-01

    Computer simulations of physical systems under extreme conditions (high density, temperature, etc.) require the availability of extensive sets of atomic data. This paper presents basic information on a self-consistent approach to calculations of radiative opacity, one of the key characteristics of such systems. After a short explanation of general concepts of the atomic physics of extreme systems, the structure of the opacity code RACHEL is discussed and some of its applications are presented.

  18. Climate change, climatic variation and extreme biological responses.

    Science.gov (United States)

    Palmer, Georgina; Platts, Philip J; Brereton, Tom; Chapman, Jason W; Dytham, Calvin; Fox, Richard; Pearce-Higgins, James W; Roy, David B; Hill, Jane K; Thomas, Chris D

    2017-06-19

    Extreme climatic events could be major drivers of biodiversity change, but it is unclear whether extreme biological changes are (i) individualistic (species- or group-specific), (ii) commonly associated with unusual climatic events and/or (iii) important determinants of long-term population trends. Using population time series for 238 widespread species (207 Lepidoptera and 31 birds) in England since 1968, we found that population 'crashes' (outliers in terms of species' year-to-year population changes) were 46% more frequent than population 'explosions'. (i) Every year, at least three species experienced extreme changes in population size, and in 41 of the 44 years considered, some species experienced population crashes while others simultaneously experienced population explosions. This suggests that, even within the same broad taxonomic groups, species are exhibiting individualistic dynamics, most probably driven by their responses to different, short-term events associated with climatic variability. (ii) Six out of 44 years showed a significant excess of species experiencing extreme population changes (5 years for Lepidoptera, 1 for birds). These 'consensus years' were associated with climatically extreme years, consistent with a link between extreme population responses and climatic variability, although not all climatically extreme years generated excess numbers of extreme population responses. (iii) Links between extreme population changes and long-term population trends were absent in Lepidoptera and modest (but significant) in birds. We conclude that extreme biological responses are individualistic, in the sense that the extreme population changes of most species are taking place in different years, and that long-term trends of widespread species have not, to date, been dominated by these extreme changes.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'. © 2017 The Authors.

  19. Extreme Programming Pocket Guide

    CERN Document Server

    Chromatic

    2003-01-01

    Extreme Programming (XP) is a radical new approach to software development that has been accepted quickly because its core practices--the need for constant testing, programming in pairs, inviting customer input, and the communal ownership of code--resonate with developers everywhere. Although many developers feel that XP is rooted in commonsense, its vastly different approach can bring challenges, frustrations, and constant demands on your patience. Unless you've got unlimited time (and who does these days?), you can't always stop to thumb through hundreds of pages to find the piece of info

  20. Upper extremity golf injuries.

    Science.gov (United States)

    Cohn, Michael A; Lee, Steven K; Strauss, Eric J

    2013-01-01

    Golf is a global sport enjoyed by an estimated 60 million people around the world. Despite the common misconception that the risk of injury during the play of golf is minimal, golfers are subject to a myriad of potential pathologies. While the majority of injuries in golf are attributable to overuse, acute traumatic injuries can also occur. As the body's direct link to the golf club, the upper extremities are especially prone to injury. A thorough appreciation of the risk factors and patterns of injury will afford accurate diagnosis, treatment, and prevention of further injury.

  1. Comparison of short-lived medical isotopes activation by laser thin target induced protons and conventional cyclotron proton beams

    Science.gov (United States)

    Murray, Joseph; Dudnikova, Galina; Liu, Tung-Chang; Papadopoulos, Dennis; Sagdeev, Roald; Su, J. J.; UMD MicroPET Team

    2014-10-01

    Production diagnostic or therapeutic nuclear medicines are either by nuclear reactors or by ion accelerators. In general, diagnostic nuclear radioisotopes have a very short half-life varying from tens of minutes for PET tracers and few hours for SPECT tracers. Thus supplies of PET and SPECT radiotracers are limited by regional production facilities. For example 18F-fluorodeoxyglucose (FDG) is the most desired tracer for positron emission tomography because its 110 minutes half-life is sufficient long for transport from production facilities to nearby users. From nuclear activation to completing image taking must be done within 4 hours. Decentralized production of diagnostic radioisotopes will be idea to make high specific activity radiotracers available to researches and clinicians. 11 C, 13 N, 15 O and 18 F can be produced in the energy range from 10-20 MeV by protons. Protons of energies up to tens of MeV generated by intense laser interacting with hydrogen containing targets have been demonstrated by many groups in the past decade. We use 2D PIC code for proton acceleration, Geant4 Monte Carlo code for nuclei activation to compare the yields and specific activities of short-lived isotopes produced by cyclotron proton beams and laser driven protons.

  2. Censored rainfall modelling for estimation of fine-scale extremes

    Science.gov (United States)

    Cross, David; Onof, Christian; Winter, Hugo; Bernardara, Pietro

    2018-01-01

    Reliable estimation of rainfall extremes is essential for drainage system design, flood mitigation, and risk quantification. However, traditional techniques lack physical realism and extrapolation can be highly uncertain. In this study, we improve the physical basis for short-duration extreme rainfall estimation by simulating the heavy portion of the rainfall record mechanistically using the Bartlett-Lewis rectangular pulse (BLRP) model. Mechanistic rainfall models have had a tendency to underestimate rainfall extremes at fine temporal scales. Despite this, the simple process representation of rectangular pulse models is appealing in the context of extreme rainfall estimation because it emulates the known phenomenology of rainfall generation. A censored approach to Bartlett-Lewis model calibration is proposed and performed for single-site rainfall from two gauges in the UK and Germany. Extreme rainfall estimation is performed for each gauge at the 5, 15, and 60 min resolutions, and considerations for censor selection discussed.

  3. Estimating the mean and variance of measurements from serial radioactive decay schemes with emphasis on 222Rn and its short-lived progeny

    International Nuclear Information System (INIS)

    Inkret, W.C.; Borak, T.B.; Boes, D.C.

    1990-01-01

    Classically, the mean and variance of radioactivity measurements are estimated from poisson distributions. However, the random distribution of observed events is not poisson when the half-life is short compared with the interval of observation or when more than one event can be associated with a single initial atom. Procedures were developed to estimate the mean and variance of single measurements of serial radioactive processes. Results revealed that observations from the three consecutive alpha emissions beginning with 222 Rn are positively correlated. Since the poisson estimator ignores covariance terms, it underestimates the true variance of the measurement. The reverse is true for mixtures of radon daughters only. (author)

  4. Flooding hazards from sea extremes and subsidence

    DEFF Research Database (Denmark)

    Sørensen, Carlo; Vognsen, Karsten; Broge, Niels

    2015-01-01

    of tide gauge records, statistics that allow also for projections of SLR, meteorological variability, and extremes with a very low probability of occurrence are provided. Land movement is researched with a focus on short term surface height variability in the groundwater-ocean interface that, together...... with longer term processes, may cause substantial subsidence and impact future water management and adaptation strategies in flood prone coastal areas. Field studies’ results from repeated precise levelling, GPS setups, and ocean and groundwater level monitoring in Thyborøn and Aarhus are integrated...

  5. Coherent harmonics generated by a super-short electron pulse

    International Nuclear Information System (INIS)

    Ding Wu

    1996-01-01

    A novel mechanism generating superradiance harmonics is found. In this superradiance harmonics, the temporal width of harmonics is extremely short, the ratio of high harmonic fundamental wave is much higher than the known superradiance harmonics

  6. Investigating NARCCAP Precipitation Extremes via Bivariate Extreme Value Theory (Invited)

    Science.gov (United States)

    Weller, G. B.; Cooley, D. S.; Sain, S. R.; Bukovsky, M. S.; Mearns, L. O.

    2013-12-01

    We introduce methodology from statistical extreme value theory to examine the ability of reanalysis-drive regional climate models to simulate past daily precipitation extremes. Going beyond a comparison of summary statistics such as 20-year return values, we study whether the most extreme precipitation events produced by climate model simulations exhibit correspondence to the most extreme events seen in observational records. The extent of this correspondence is formulated via the statistical concept of tail dependence. We examine several case studies of extreme precipitation events simulated by the six models of the North American Regional Climate Change Assessment Program (NARCCAP) driven by NCEP reanalysis. It is found that the NARCCAP models generally reproduce daily winter precipitation extremes along the Pacific coast quite well; in contrast, simulation of past daily summer precipitation extremes in a central US region is poor. Some differences in the strength of extremal correspondence are seen in the central region between models which employ spectral nudging and those which do not. We demonstrate how these techniques may be used to draw a link between extreme precipitation events and large-scale atmospheric drivers, as well as to downscale extreme precipitation simulated by a future run of a regional climate model. Specifically, we examine potential future changes in the nature of extreme precipitation along the Pacific coast produced by the pineapple express (PE) phenomenon. A link between extreme precipitation events and a "PE Index" derived from North Pacific sea-surface pressure fields is found. This link is used to study PE-influenced extreme precipitation produced by a future-scenario climate model run.

  7. Transient nanobubbles in short-time electrolysis

    NARCIS (Netherlands)

    Svetovoy, Vitaly; Sanders, Remco G.P.; Elwenspoek, Michael Curt

    2013-01-01

    Water electrolysis in a microsystem is observed and analyzed on a short-time scale of ∼10 μs. The very unusual properties of the process are stressed. An extremely high current density is observed because the process is not limited by the diffusion of electroactive species. The high current is

  8. Extreme coal handling

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, S; Homleid, D. [Air Control Science Inc. (United States)

    2004-04-01

    Within the journals 'Focus on O & M' is a short article describing modifications to coal handling systems at Eielson Air Force Base near Fairbanks, Alaska, which is supplied with power and heat from a subbituminous coal-fired central plant. Measures to reduce dust include addition of an enclosed recirculation chamber at each transfer point and new chute designs to reduce coal velocity, turbulence, and induced air. The modifications were developed by Air Control Science (ACS). 7 figs., 1 tab.

  9. Multifractal Conceptualisation of Hydro-Meteorological Extremes

    Science.gov (United States)

    Tchiguirinskaia, I.; Schertzer, D.; Lovejoy, S.

    2009-04-01

    Hydrology and more generally sciences involved in water resources management, technological or operational developments face a fundamental difficulty: the extreme variability of hydro-meteorological fields. It clearly appears today that this variability is a function of the observation scale and yield hydro-meteorological hazards. Throughout the world, the development of multifractal theory offers new techniques for handling such non-classical variability over wide ranges of time and space scales. The resulting stochastic simulations with a very limited number of parameters well reproduce the long range dependencies and the clustering of rainfall extremes often yielding fat tailed (i.e., an algebraic type) probability distributions. The goal of this work was to investigate the ability of using very short or incomplete data records for reliable statistical predictions of the extremes. In particular we discuss how to evaluate the uncertainty in the empirical or semi-analytical multifractal outcomes. We consider three main aspects of the evaluation, such as the scaling adequacy, the multifractal parameter estimation error and the quantile estimation error. We first use the multiplicative cascade model to generate long series of multifractal data. The simulated samples had to cover the range of the universal multifractal parameters widely available in the scientific literature for the rainfall and river discharges. Using these long multifractal series and their sub-samples, we defined a metric for parameter estimation error. Then using the sets of estimated parameters, we obtained the quantile values for a range of excedance probabilities from 5% to 0.01%. Plotting the error bars on a quantile plot enable an approximation of confidence intervals that would be particularly important for the predictions of multifractal extremes. We finally illustrate the efficiency of such concept on its application to a large database (more than 16000 selected stations over USA and

  10. Estimates of extremes in the best of all possible worlds

    NARCIS (Netherlands)

    Van Nooyen, R.R.P.; Kolechkina, A.G.

    2012-01-01

    In applied hydrology the question of the probability of exceeding a certain value occurs regularly. Often it is in a context where extrapolation from a relatively short time series is needed. It is well known that in its simplest form extreme value theory applies to independent identically

  11. Are BALQSOs extreme accretors?

    Science.gov (United States)

    Yuan, M. J.; Wills, B. J.

    2002-12-01

    Broad Absorption Line (BAL) QSOs are QSOs with massive absorbing outflows up to 0.2c. Two hypothesis have been suggested in the past about the nature of BALQSOs: Every QSO might have BAL outflow with some covering factor. BALQSOs are those which happen to have outflow along our line of sight. BALQSOs have intrinsically different physical properties than non-BALQSOs. Based on BALQSO's optical emission properties and a large set of correlations linking many general QSO emission line and continuum properties, it has been suggested that BALQSOs might accrete at near Eddington limit with abundant of fuel supplies. With new BALQSO Hβ region spectroscopic observation conducted at UKIRT and re-analysis of literature data for low and high redshift non-BALQSOs, We confirm that BALQSOs have extreme Fe II and [O III] emission line properties. Using results derived from the latest QSO Hβ region reverberation mapping, we calculated Eddington ratios (˙ {M}/˙ {M}Edd) for our BAL and non-BALQSOs. The Fe II and [O III] strengths are strongly correlated with Eddington ratios. Those correlations link Eddington ratio to a large set of general QSO properties through the Boroson & Green Eigenvector 1. We find that BALQSOs have Eddington ratios close to 1. However, all high redshift, high luminosity QSOs have rather high Eddington ratios. We argue that this is a side effect from selecting the brightest objects. In fact, our high redshift sample might constitute BALQSO's high Eddington ratio orientation parent population.

  12. Extreme winds in Denmark

    DEFF Research Database (Denmark)

    Kristensen, L.; Rathmann, O.; Hansen, S.O.

    2000-01-01

    (Technical Report, Danish Technical press, 1970) and by Abild (Technical Report R-522 (EN), Riso National Laboratory, 1994). A short discussion of the wind storm on the 3rd of December 1999 is included. It is demonstrated how the data can be applied to non-standard situations where the roughness length......Wind-speed data from four sites in Denmark have been analyzed in order to obtain estimates of the basic wind velocity, defined as the 50 yr wind speed (10 min averages) under standard conditions, i.e., 10 m over a homogeneous terrain with the roughness length 0.05 m, The sites are Skjern (15 yr......), Kegnaes (7 yr), Sprogo (20 yr), and Tystofte (16 yr). The measured data are wind speed, wind direction, temperature and pressure. The wind records are cleaned for terrain effects by means of WASP (Mortensew ct al., Technical Report I-666 (EN), Riso National Laboratory, 1993. Vol. 2. User's Guide...

  13. Development of new organometallic species for the labelling of radiotracers with short half-lives radioisotopes

    International Nuclear Information System (INIS)

    Huet-Dales, A.

    2003-11-01

    The reactivity of clean organotins have been studied in the Stille coupling reaction in fast conditions, witch can be used with short half-life radioisotope. In a first part, development of the reaction conditions have been studied for the transfer of a methyl group by the Stille coupling reaction, via the synthesis of the correspond mono-organotin. The reaction time was optimized onto model compounds in 12-carbon and 11-carbon chemistry. In a second part, this methodology was applied to the synthesis of NK3 receptors radioligands, in 12-carbon and 11-carbon chemistry. Biological studies showed that these ligands have a good affinity with NK3 receptors, and are potential positron emission tomography tracers. (author)

  14. Limited BRC rulemaking: Regulatory approach and experience in Texas for short-lived radioactive waste

    International Nuclear Information System (INIS)

    McBurney, Ruth E.; Pollard, Christine G.

    1992-01-01

    In 1987, the Texas Department of Health (TDH) implemented a rule to allow, under certain conditions, wastes containing limited concentrations of short- lived radionuclides (less than 300-day half-life) to be disposed of in Type I sanitary landfills. The rule was based on a technical analysis that demonstrated the degree of safety for approximately 340 m of radioactive waste generated annually in Texas and identified major restrictions and conditions for disposal. TDH's Bureau of Radiation Control staff have been able to maintain an account of licensees utilizing the rule during the past years. Several research and industrial facilities in the state have saved significantly on waste disposal expenses. Public concerns and economic impacts for licensees as well as other regulatory aspects and experiences with the rule are discussed. (author)

  15. High Accuracy mass Measurement of the very Short-Lived Halo Nuclide $^{11}$Li

    CERN Multimedia

    Le scornet, G

    2002-01-01

    The archetypal halo nuclide $^{11}$Li has now attracted a wealth of experimental and theoretical attention. The most outstanding property of this nuclide, its extended radius that makes it as big as $^{48}$Ca, is highly dependent on the binding energy of the two neutrons forming the halo. New generation experiments using radioactive beams with elastic proton scattering, knock-out and transfer reactions, together with $\\textit{ab initio}$ calculations require the tightening of the constraint on the binding energy. Good metrology also requires confirmation of the sole existing precision result to guard against a possible systematic deviation (or mistake). We propose a high accuracy mass determintation of $^{11}$Li, a particularly challenging task due to its very short half-life of 8.6 ms, but one perfectly suiting the MISTRAL spectrometer, now commissioned at ISOLDE. We request 15 shifts of beam time.

  16. Transport of short lived radioactive contaminants with prologed half-lives of daughters through river water

    International Nuclear Information System (INIS)

    Metwally, S.M.; Prohl, G.

    2005-01-01

    One of the main pathways for transporting contaminants to other parts in the environment, are rivers. This work is devoted for deriving and assessment the concentration of soluble radio contaminants along a river at any time after discharge, including the short-lived radionuclides in comparison with the discharge time interval, and prolonged half-life of the produced daughter nuclei. The assumed boundary conditions and deduced formulas can be applied either in case of accidental release or discharge under authority control. The formulas determining the produced daughter nuclei concentration require inequality of the parent and daughter nuclei half-lives. Because of the regional variation of river morphology, the assumed constancy of the flow velocity and dispersion coefficient requires dividing the river path into zones of similar hydrologic characteristics

  17. Natural short sleeper

    Science.gov (United States)

    Sleep - natural short sleeper ... 7 to 9 hours of sleep each night. Short sleepers sleep less than 75% of what is normal for their age. Natural short sleepers are different from people who chronically do ...

  18. Towards short wavelengths FELs workshop

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Winick, H.

    1993-01-01

    This workshop was caged because of the growing perception in the FEL source community that recent advances have made it possible to extend FEL operation to wavelengths about two orders of magnitude shorter than the 240 nm that has been achieved to date. In addition short wavelength FELs offer the possibilities of extremely high peak power (several gigawatts) and very short pulses (of the order of 100 fs). Several groups in the USA are developing plans for such short wavelength FEL facilities. However, reviewers of these plans have pointed out that it would be highly desirable to first carry out proof-of-principle experiments at longer wavelengths to increase confidence that the shorter wavelength devices will indeed perform as calculated. The need for such experiments has now been broadly accepted by the FEL community. Such experiments were the main focus of this workshop as described in the following objectives distributed to attendees: (1) Define measurements needed to gain confidence that short wavelength FELs will perform as calculated. (2) List possible hardware that could be used to carry out these measurements in the near term. (3) Define a prioritized FEL physics experimental program and suggested timetable. (4) Form collaborative teams to carry out this program

  19. Towards short wavelengths FELs workshop

    Science.gov (United States)

    Ben-Zvi, I.; Winick, H.

    1993-11-01

    This workshop was caged because of the growing perception in the FEL source community that recent advances have made it possible to extend FEL operation to wavelengths about two orders of magnitude shorter than the 240 nm that has been achieved to date. In addition short wavelength FEL's offer the possibilities of extremely high peak power (several gigawatts) and very short pulses (of the order of 100 fs). Several groups in the USA are developing plans for such short wavelength FEL facilities. However, reviewers of these plans have pointed out that it would be highly desirable to first carry out proof-of-principle experiments at longer wavelengths to increase confidence that the shorter wavelength devices will indeed perform as calculated. The need for such experiments has now been broadly accepted by the FEL community. Such experiments were the main focus of this workshop as described in the following objectives distributed to attendees: (1) Define measurements needed to gain confidence that short wavelength FEL's will perform as calculated. (2) List possible hardware that could be used to carry out these measurements in the near term. (3) Define a prioritized FEL physics experimental program and suggested timetable. (4) Form collaborative teams to carry out this program.

  20. A note on extreme sets

    Directory of Open Access Journals (Sweden)

    Radosław Cymer

    2017-10-01

    Full Text Available In decomposition theory, extreme sets have been studied extensively due to its connection to perfect matchings in a graph. In this paper, we first define extreme sets with respect to degree-matchings and next investigate some of their properties. In particular, we prove the generalized Decomposition Theorem and give a characterization for the set of all extreme vertices in a graph.

  1. Thyroid Storm with Heart Failure Treated with a Short-acting Beta-adrenoreceptor Blocker, Landiolol Hydrochloride.

    Science.gov (United States)

    Yamashita, Yugo; Iguchi, Moritake; Nakatani, Rieko; Usui, Takeshi; Takagi, Daisuke; Hamatani, Yasuhiro; Unoki, Takashi; Ishii, Mitsuru; Ogawa, Hisashi; Masunaga, Nobutoyo; Abe, Mitsuru; Akao, Masaharu

    2015-01-01

    Beta-adrenoreceptor blockers are essential in controlling the peripheral actions of thyroid hormones and a rapid heart rate in patients with thyroid storm, although they should be used with great caution when there is the potential for heart failure. A 67-year-old woman was diagnosed as having thyroid storm in addition to marked tachycardia with atrial fibrillation and heart failure associated with a reduced left ventricular function. The administration of an oral beta blocker, bisoprolol fumarate, induced hypotension and was not tolerable for the patient, whereas landiolol hydrochloride, a short-acting intravenous beta-adrenoreceptor blocker with high cardioselectivity and a short elimination half-life, was useful for controlling the patient's tachycardia and heart failure without causing hemodynamic deterioration.

  2. Likelihood estimators for multivariate extremes

    KAUST Repository

    Huser, Raphaë l; Davison, Anthony C.; Genton, Marc G.

    2015-01-01

    The main approach to inference for multivariate extremes consists in approximating the joint upper tail of the observations by a parametric family arising in the limit for extreme events. The latter may be expressed in terms of componentwise maxima, high threshold exceedances or point processes, yielding different but related asymptotic characterizations and estimators. The present paper clarifies the connections between the main likelihood estimators, and assesses their practical performance. We investigate their ability to estimate the extremal dependence structure and to predict future extremes, using exact calculations and simulation, in the case of the logistic model.

  3. Likelihood estimators for multivariate extremes

    KAUST Repository

    Huser, Raphaël

    2015-11-17

    The main approach to inference for multivariate extremes consists in approximating the joint upper tail of the observations by a parametric family arising in the limit for extreme events. The latter may be expressed in terms of componentwise maxima, high threshold exceedances or point processes, yielding different but related asymptotic characterizations and estimators. The present paper clarifies the connections between the main likelihood estimators, and assesses their practical performance. We investigate their ability to estimate the extremal dependence structure and to predict future extremes, using exact calculations and simulation, in the case of the logistic model.

  4. Liquid Water Restricts Habitability in Extreme Deserts

    Science.gov (United States)

    Cockell, Charles S.; Brown, Sarah; Landenmark, Hanna; Samuels, Toby; Siddall, Rebecca; Wadsworth, Jennifer

    2017-04-01

    Liquid water is a requirement for biochemistry, yet under some circumstances it is deleterious to life. Here, we show that liquid water reduces the upper temperature survival limit for two extremophilic photosynthetic microorganisms (Gloeocapsa and Chroococcidiopsis spp.) by greater than 40°C under hydrated conditions compared to desiccated conditions. Under hydrated conditions, thermal stress causes protein inactivation as shown by the fluorescein diacetate assay. The presence of water was also found to enhance the deleterious effects of freeze-thaw in Chroococcidiopsis sp. In the presence of water, short-wavelength UV radiation more effectively kills Gloeocapsa sp. colonies, which we hypothesize is caused by factors including the greater penetration of UV radiation into hydrated colonies compared to desiccated colonies. The data predict that deserts where maximum thermal stress or irradiation occurs in conjunction with the presence of liquid water may be less habitable to some organisms than more extreme arid deserts where organisms can dehydrate prior to being exposed to these extremes, thus minimizing thermal and radiation damage. Life in extreme deserts is poised between the deleterious effects of the presence and the lack of liquid water.

  5. Liquid Water Restricts Habitability in Extreme Deserts.

    Science.gov (United States)

    Cockell, Charles S; Brown, Sarah; Landenmark, Hanna; Samuels, Toby; Siddall, Rebecca; Wadsworth, Jennifer

    2017-04-01

    Liquid water is a requirement for biochemistry, yet under some circumstances it is deleterious to life. Here, we show that liquid water reduces the upper temperature survival limit for two extremophilic photosynthetic microorganisms (Gloeocapsa and Chroococcidiopsis spp.) by greater than 40°C under hydrated conditions compared to desiccated conditions. Under hydrated conditions, thermal stress causes protein inactivation as shown by the fluorescein diacetate assay. The presence of water was also found to enhance the deleterious effects of freeze-thaw in Chroococcidiopsis sp. In the presence of water, short-wavelength UV radiation more effectively kills Gloeocapsa sp. colonies, which we hypothesize is caused by factors including the greater penetration of UV radiation into hydrated colonies compared to desiccated colonies. The data predict that deserts where maximum thermal stress or irradiation occurs in conjunction with the presence of liquid water may be less habitable to some organisms than more extreme arid deserts where organisms can dehydrate prior to being exposed to these extremes, thus minimizing thermal and radiation damage. Life in extreme deserts is poised between the deleterious effects of the presence and the lack of liquid water. Key Words: Deserts-Extremophiles-Stress-High temperatures-UV radiation-Desiccation. Astrobiology 17, 309-318.

  6. Further outlooks: extremely uncomfortable; Die weiteren Aussichten: extrem ungemuetlich

    Energy Technology Data Exchange (ETDEWEB)

    Resenhoeft, T.

    2006-07-01

    Climate is changing extremely in the last decades. Scientists dealing with extreme weather, should not only stare at computer simulations. They have also to turn towards psyche, seriously personal experiences, knowing statistics, relativise supposed sensational reports and last not least collecting more data. (GL)

  7. Assessing Climate Variability using Extreme Rainfall and ...

    African Journals Online (AJOL)

    user1

    extreme frequency); the average intensity of rainfall from extreme events ... frequency and extreme intensity indices, suggesting that extreme events are more frequent and intense during years with high rainfall. The proportion of total rainfall from ...

  8. Correlation dimension and phase space contraction via extreme value theory

    Science.gov (United States)

    Faranda, Davide; Vaienti, Sandro

    2018-04-01

    We show how to obtain theoretical and numerical estimates of correlation dimension and phase space contraction by using the extreme value theory. The maxima of suitable observables sampled along the trajectory of a chaotic dynamical system converge asymptotically to classical extreme value laws where: (i) the inverse of the scale parameter gives the correlation dimension and (ii) the extremal index is associated with the rate of phase space contraction for backward iteration, which in dimension 1 and 2, is closely related to the positive Lyapunov exponent and in higher dimensions is related to the metric entropy. We call it the Dynamical Extremal Index. Numerical estimates are straightforward to obtain as they imply just a simple fit to a univariate distribution. Numerical tests range from low dimensional maps, to generalized Henon maps and climate data. The estimates of the indicators are particularly robust even with relatively short time series.

  9. Management of the mangled extremity

    NARCIS (Netherlands)

    Prasarn, Mark L.; Helfet, David L.; Kloen, Peter

    2012-01-01

    The management of a mangled extremity continues to be a matter of debate. With modern advances in trauma resuscitation, microvascular tissue transfer, and fracture fixation, severe traumatic extremity injuries that would historically have been amputated are often salvaged. Even if preserving a

  10. A decade of weather extremes

    NARCIS (Netherlands)

    Coumou, Dim; Rahmstorf, Stefan

    The ostensibly large number of recent extreme weather events has triggered intensive discussions, both in- and outside the scientific community, on whether they are related to global warming. Here, we review the evidence and argue that for some types of extreme - notably heatwaves, but also

  11. Attitude extremity, consensus and diagnosticity

    NARCIS (Netherlands)

    van der Pligt, J.; Ester, P.; van der Linden, J.

    1983-01-01

    Studied the effects of attitude extremity on perceived consensus and willingness to ascribe trait terms to others with either pro- or antinuclear attitudes. 611 Ss rated their attitudes toward nuclear energy on a 5-point scale. Results show that attitude extremity affected consensus estimates. Trait

  12. Photoionization capable, extreme and vacuum ultraviolet emission in developing low temperature plasmas in air

    NARCIS (Netherlands)

    Stephens, J.; Fierro, A.; Beeson, S.; Laity, G.; Trienekens, D.; Joshi, R.P.; Dickens, J.; Neuber, A.

    2016-01-01

    Experimental observation of photoionization capable extreme ultraviolet and vacuum ultraviolet emission from nanosecond timescale, developing low temperature plasmas (i.e. streamer discharges) in atmospheric air is presented. Applying short high voltage pulses enabled the observation of the onset of

  13. Matching the Decay Half-Life with the Biological Half-Life: ImmunoPET Imaging with 44Sc-Labeled Cetuximab Fab Fragment

    Science.gov (United States)

    2015-01-01

    Scandium-44 (t1/2 = 3.9 h) is a relatively new radioisotope of potential interest for use in clinical positron emission tomography (PET). Herein, we report, for the first time, the room-temperature radiolabeling of proteins with 44Sc for in vivo PET imaging. For this purpose, the Fab fragment of Cetuximab, a monoclonal antibody that binds with high affinity to epidermal growth factor receptor (EGFR), was generated and conjugated with N-[(R)-2-amino-3-(para-isothiocyanato-phenyl)propyl]-trans-(S,S)-cyclohexane-1,2-diamine-N,N,N′,N″,N″-pentaacetic acid (CHX-A″-DTPA). The high purity of Cetuximab-Fab was confirmed by SDS-PAGE and mass spectrometry. The potential of the bioconjugate for PET imaging of EGFR expression in human glioblastoma (U87MG) tumor-bearing mice was investigated after 44Sc labeling. PET imaging revealed rapid tumor uptake (maximum uptake of ∼12% ID/g at 4 h postinjection) of 44Sc–CHX-A″-DTPA–Cetuximab-Fab with excellent tumor-to-background ratio, which might allow for same day PET imaging in future clinical studies. Immunofluorescence staining was conducted to correlate tracer uptake in the tumor and normal tissues with EGFR expression. This successful strategy for immunoPET imaging of EGFR expression using 44Sc–CHX-A″-DTPA–Cetuximab-Fab can make clinically translatable advances to select the right population of patients for EGFR-targeted therapy and also to monitor the therapeutic efficacy of anti-EGFR treatments. PMID:25389697

  14. Fast neutron activation analysis using short-lived radionuclides

    International Nuclear Information System (INIS)

    Salma, I.; Zemplen-Papp, E.

    1993-01-01

    Fast neutron activation analysis experiments were performed to investigate the analytical possibilities and prospective utilization of short-lived activation products. A rapid pneumatic transfer system for use with neutron generators has been installed and applied for detecting radionuclides with a half-life from ∼300 ms to 20 s. The transport time for samples of total mass of 1-4 g is between 130 and 160 ms for pressurized air of 0.1-0.4 MPa. The reproducibility of transport times is less than 2%. The employed method of correcting time-dependent counting losses is based on the virtual pulse generator principle. The measuring equipment consists of CAMAC modules and a special gating circuit. Typical time distributions of counting losses are presented. The same 14 elements were studied by the conventional activation method (single irradiation and single counting) by both a typical pneumatic transport system (run time 3 s) and the fast pneumatic transport facility. Furthermore, the influence of the cyclic activation technique on the elemental sensitivities was investigated. (author) 15 refs.; 5 figs.; 3 tabs

  15. Spatial dependence of extreme rainfall

    Science.gov (United States)

    Radi, Noor Fadhilah Ahmad; Zakaria, Roslinazairimah; Satari, Siti Zanariah; Azman, Muhammad Az-zuhri

    2017-05-01

    This study aims to model the spatial extreme daily rainfall process using the max-stable model. The max-stable model is used to capture the dependence structure of spatial properties of extreme rainfall. Three models from max-stable are considered namely Smith, Schlather and Brown-Resnick models. The methods are applied on 12 selected rainfall stations in Kelantan, Malaysia. Most of the extreme rainfall data occur during wet season from October to December of 1971 to 2012. This period is chosen to assure the available data is enough to satisfy the assumption of stationarity. The dependence parameters including the range and smoothness, are estimated using composite likelihood approach. Then, the bootstrap approach is applied to generate synthetic extreme rainfall data for all models using the estimated dependence parameters. The goodness of fit between the observed extreme rainfall and the synthetic data is assessed using the composite likelihood information criterion (CLIC). Results show that Schlather model is the best followed by Brown-Resnick and Smith models based on the smallest CLIC's value. Thus, the max-stable model is suitable to be used to model extreme rainfall in Kelantan. The study on spatial dependence in extreme rainfall modelling is important to reduce the uncertainties of the point estimates for the tail index. If the spatial dependency is estimated individually, the uncertainties will be large. Furthermore, in the case of joint return level is of interest, taking into accounts the spatial dependence properties will improve the estimation process.

  16. Evolution caused by extreme events.

    Science.gov (United States)

    Grant, Peter R; Grant, B Rosemary; Huey, Raymond B; Johnson, Marc T J; Knoll, Andrew H; Schmitt, Johanna

    2017-06-19

    Extreme events can be a major driver of evolutionary change over geological and contemporary timescales. Outstanding examples are evolutionary diversification following mass extinctions caused by extreme volcanism or asteroid impact. The evolution of organisms in contemporary time is typically viewed as a gradual and incremental process that results from genetic change, environmental perturbation or both. However, contemporary environments occasionally experience strong perturbations such as heat waves, floods, hurricanes, droughts and pest outbreaks. These extreme events set up strong selection pressures on organisms, and are small-scale analogues of the dramatic changes documented in the fossil record. Because extreme events are rare, almost by definition, they are difficult to study. So far most attention has been given to their ecological rather than to their evolutionary consequences. We review several case studies of contemporary evolution in response to two types of extreme environmental perturbations, episodic (pulse) or prolonged (press). Evolution is most likely to occur when extreme events alter community composition. We encourage investigators to be prepared for evolutionary change in response to rare events during long-term field studies.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'. © 2017 The Author(s).

  17. Statistical Model of Extreme Shear

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Hansen, Kurt Schaldemose

    2004-01-01

    In order to continue cost-optimisation of modern large wind turbines, it is important to continously increase the knowledge on wind field parameters relevant to design loads. This paper presents a general statistical model that offers site-specific prediction of the probability density function...... by a model that, on a statistically consistent basis, describe the most likely spatial shape of an extreme wind shear event. Predictions from the model have been compared with results from an extreme value data analysis, based on a large number of high-sampled full-scale time series measurements...... are consistent, given the inevitabel uncertainties associated with model as well as with the extreme value data analysis. Keywords: Statistical model, extreme wind conditions, statistical analysis, turbulence, wind loading, statistical analysis, turbulence, wind loading, wind shear, wind turbines....

  18. Racial Extremism in the Army

    National Research Council Canada - National Science Library

    Hudson, Walter M

    1998-01-01

    ... modem phenomenon of "skinheads." I then discuss the history of white supremacist extremism in the Army, culminating in the December, 1995 murders of two black civilians by soldiers assigned to the 82d Airborne Division at Fort Bragg, North Carolina...

  19. Legacies from extreme drought increase ecosystem sensitivity to future extremes

    Science.gov (United States)

    Smith, M. D.; Knapp, A.; Hoover, D. L.; Avolio, M. L.; Felton, A. J.; Wilcox, K. R.

    2016-12-01

    Climate extremes, such as drought, are increasing in frequency and intensity, and the ecological consequences of these extreme events can be substantial and widespread. Although there is still much to be learned about how ecosystems will respond to an intensification of drought, even less is known about the factors that determine post-drought recovery of ecosystem function. Such knowledge is particularly important because post-drought recovery periods can be protracted depending on the extent to which key plant populations, community structure and biogeochemical processes are affected. These drought legacies may alter ecosystem function for many years post-drought and may impact future sensitivity to climate extremes. We experimentally imposed two extreme growing season droughts in a central US grassland to assess the impacts of repeated droughts on ecosystem resistance (response) and resilience (recovery). We found that this grassland was not resistant to the first extreme drought due to reduced productivity and differential sensitivity of the co-dominant C4 grass (Andropogon gerardii) and C3 forb (Solidago canadensis) species. This differential sensitivity led to a reordering of species abundances within the plant community. Yet, despite this large shift in plant community composition, which persisted post-drought, the grassland was highly resilient post-drought, due to increased abundance of the dominant C4 grass. Because of this shift to increased C4 grass dominance, we expected that previously-droughted grassland would be more resistant to a second extreme drought. However, contrary to these expectations, previously droughted grassland was more sensitive to drought than grassland that had not experienced drought. Thus, our result suggest that legacies of drought (shift in community composition) may increase ecosystem sensitivity to future extreme events.

  20. Extreme-Scale De Novo Genome Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Georganas, Evangelos [Intel Corporation, Santa Clara, CA (United States); Hofmeyr, Steven [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint Genome Inst.; Egan, Rob [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Computational Research Division; Buluc, Aydin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint Genome Inst.; Oliker, Leonid [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint Genome Inst.; Rokhsar, Daniel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Computational Research Division; Yelick, Katherine [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint Genome Inst.

    2017-09-26

    De novo whole genome assembly reconstructs genomic sequence from short, overlapping, and potentially erroneous DNA segments and is one of the most important computations in modern genomics. This work presents HipMER, a high-quality end-to-end de novo assembler designed for extreme scale analysis, via efficient parallelization of the Meraculous code. Genome assembly software has many components, each of which stresses different components of a computer system. This chapter explains the computational challenges involved in each step of the HipMer pipeline, the key distributed data structures, and communication costs in detail. We present performance results of assembling the human genome and the large hexaploid wheat genome on large supercomputers up to tens of thousands of cores.

  1. Shortness of Breath

    Science.gov (United States)

    ... filled with air (called pneumotho- rax), it will hinder expansion of the lung, resulting in shortness of ... of Chest Physi- cians. Shortness of Breath: Patient Education. http: / / www. onebreath. org/ document. doc? id= 113. ...

  2. Short-circuit logic

    NARCIS (Netherlands)

    Bergstra, J.A.; Ponse, A.

    2010-01-01

    Short-circuit evaluation denotes the semantics of propositional connectives in which the second argument is only evaluated if the first argument does not suffice to determine the value of the expression. In programming, short-circuit evaluation is widely used. A short-circuit logic is a variant of

  3. Shapeable short circuit resistant capacitor

    Science.gov (United States)

    Taylor, Ralph S.; Myers, John D.; Baney, William J.

    2015-10-06

    A ceramic short circuit resistant capacitor that is bendable and/or shapeable to provide a multiple layer capacitor that is extremely compact and amenable to desirable geometries. The capacitor that exhibits a benign failure mode in which a multitude of discrete failure events result in a gradual loss of capacitance. Each event is a localized event in which localized heating causes an adjacent portion of one or both of the electrodes to vaporize, physically cleaning away electrode material from the failure site. A first metal electrode, a second metal electrode, and a ceramic dielectric layer between the electrodes are thin enough to be formed in a serpentine-arrangement with gaps between the first electrode and the second electrode that allow venting of vaporized electrode material in the event of a benign failure.

  4. The Long and the Short of It

    Science.gov (United States)

    2006-01-01

    Gamma-Ray bursts, the extreme explosions that mark the birth of black holes, come in two flavors, long bursts lasting a few seconds or more, and short bursts lasting for less than a second. The mechanisms giving rise to these two types of bursts were, for a long time, unknown to astronomers. But a series of breakthroughs starting with BeppoSAX, HETE, and Swift gave astronomers some clues and confidence about the nature of long and short bursts. Long bursts mark the collapse of a young, extremely massive star into a black hole; short bursts mark the formation of a black hole by a merger of neutron stars (or perhaps a neutron star with a black hole to form a larger black hole). But a new observation has clouded this clear dichotomy. The picture above is an X-ray image of a gamma-ray burst, GRB 060614, taken by Swift's X-ray Telescope. This burst lasted more than 100 seconds, clearly showing that it's a long burst. But follow-up observations of the burst did not show the tell-tale signatures of a supernova explosion which should be produced by the collapse of a large star. Furthermore this burst occurred in a galaxy which has very few extremely massive stars. Does this hybrid burst represent an entirely new mechanism behind these titanic explosions? The hunt is on.

  5. Ideologies and Discourses: Extreme Narratives in Extreme Metal Music

    Directory of Open Access Journals (Sweden)

    Bojana Radovanović

    2016-10-01

    Full Text Available Historically speaking, metal music has always been about provoking a strong reaction. Depending on the characteristics of different sub-genres, one can focus on the sound, technique, visual appearance, and furthermore, the ideologies and ideas that are the foundation for each of the sub-genres. Although the majority of the metal community rejects accusations of being racially intolerant, some ideologies of extreme sub-genres (such as black metal are in fact formed around the ideas of self-conscious elitism expressed through interest in pagan mythology, racism, Nazism and fascism. There has been much interest in the Nazi era within the extreme metal scene thus influencing other sub-genres and artists. The aim of this paper is to examine various appearances of extreme narratives such as Nazism and racism in  different sub-genres of metal, bearing in mind variations dependent on geographical, political, and other factors.

  6. Near-extreme system condition and near-extreme remaining useful time for a group of products

    International Nuclear Information System (INIS)

    Wang, Hai-Kun; Li, Yan-Feng; Huang, Hong-Zhong; Jin, Tongdan

    2017-01-01

    When a group of identical products is operating in field, the aggregation of failures is a catastrophe to engineers and customers who strive to develop reliable and safe products. In order to avoid a swarm of failures in a short time, it is essential to measure the degree of dispersion from different failure times in a group of products to the first failure time. This phenomenon is relevant to the crowding of system conditions near the worst one among a group of products. The group size in this paper represents a finite number of products, instead of infinite number or a single product. We evaluate the reliability of the product fleet from two aspects. First, we define near-extreme system condition and near-extreme failure time for offline solutions, which means no online observations. Second, we apply them to a continuous degradation system that breaks down when it reaches a soft failure threshold. By using particle filtering in the framework of prognostics and health management for a group of products, we aim to estimate near-extreme system condition and further predict the remaining useful life (RUL) using online solutions. Numerical examples are provided to demonstrate the effectiveness of the proposed method. - Highlights: • The aggregation of failures is measured for a group of identical products. • The crowding of failures is quantitated by the near-extreme evaluations. • Near-extreme system condition are given for offline solutions. • Near-extreme remaining useful time are provided for online solutions.

  7. Nonlinear wave-mixing processes in the extreme ultraviolet

    International Nuclear Information System (INIS)

    Misoguti, L.; Christov, I. P.; Backus, S.; Murnane, M. M.; Kapteyn, H. C.

    2005-01-01

    We present data from two-color high-order harmonic generation in a hollow waveguide, that suggest the presence of a nonlinear-optical frequency conversion process driven by extreme ultraviolet light. By combining the fundamental and second harmonic of an 800 nm laser in a hollow-core fiber, with varying relative polarizations, and by observing the pressure and power scaling of the various harmonic orders, we show that the data are consistent with a picture where we drive the process of high-harmonic generation, which in turn drives four-wave frequency mixing processes in the extreme EUV. This work promises a method for extending nonlinear optics into the extreme ultraviolet region of the spectrum using an approach that has not previously been considered, and has compelling implications for generating tunable light at short wavelengths

  8. Coherence techniques at extreme ultraviolet wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chang [Univ. of California, Berkeley, CA (United States)

    2002-01-01

    The renaissance of Extreme Ultraviolet (EUV) and soft x-ray (SXR) optics in recent years is mainly driven by the desire of printing and observing ever smaller features, as in lithography and microscopy. This attribute is complemented by the unique opportunity for element specific identification presented by the large number of atomic resonances, essentially for all materials in this range of photon energies. Together, these have driven the need for new short-wavelength radiation sources (e.g. third generation synchrotron radiation facilities), and novel optical components, that in turn permit new research in areas that have not yet been fully explored. This dissertation is directed towards advancing this new field by contributing to the characterization of spatial coherence properties of undulator radiation and, for the first time, introducing Fourier optical elements to this short-wavelength spectral region. The first experiment in this dissertation uses the Thompson-Wolf two-pinhole method to characterize the spatial coherence properties of the undulator radiation at Beamline 12 of the Advanced Light Source. High spatial coherence EUV radiation is demonstrated with appropriate spatial filtering. The effects of small vertical source size and beamline apertures are observed. The difference in the measured horizontal and vertical coherence profile evokes further theoretical studies on coherence propagation of an EUV undulator beamline. A numerical simulation based on the Huygens-Fresnel principle is performed.

  9. Precision mass measurements of very short-lived, neutron-rich Na isotopes using a radiofrequency spectrometer

    CERN Document Server

    Lunney, M D; Doubre, H; Henry, S; Monsanglant, C; De Saint-Simon, M; Thibault, C; Toader, C F; Borcea, C; Bollen, G

    2001-01-01

    Mass measurements of high precision have been performed on sodium isotopes out to $^{30}$Na using a new technique of radiofrequency excitation of ion trajectories in a homogeneous magnetic field. This method, especially suited to very short-lived nuclides, has allowed us to significantly reduce the uncertainty in mass of the most exotic Na isotopes: a relative error of 5x10$^{-7}$ was achieved for $^{28}$Na having a half-life of only 30.5 ms and 9x10$^{-7}$ for the weakly produced $^{30}$Na. Verifying and minimizing binding energy uncertainties in this region of the nuclear chart is important for clarification of a long standing problem concerning the strength of the $N$=20 magic shell closure. These results are the fruit of the commissioning of the new experimental program Mistral.

  10. Roentgenoendovascular dilatation and recanalization of vessels of lower extremities

    International Nuclear Information System (INIS)

    Rabkin, I.Kh.; Matevosov, A.L.; Gotman, L.N.

    1987-01-01

    Advantages and disadvantages of using roentgenoendovascular dilatation (RED) of vessels of lower extremities are presented. RED is recommended in treating patients with short segmented stenoses of common and external illiac arteries and also with the similar damages of surficial femoral arteries. Dilatation is a success when there is permeability in at least one of the three central crus arteries. Success of delayed results of vessel dilatation is to a certain degree in inverse proportion to time and length of occlusion

  11. Seasonal temperature extremes in Potsdam

    Science.gov (United States)

    Kundzewicz, Zbigniew; Huang, Shaochun

    2010-12-01

    The awareness of global warming is well established and results from the observations made on thousands of stations. This paper complements the large-scale results by examining a long time-series of high-quality temperature data from the Secular Meteorological Station in Potsdam, where observation records over the last 117 years, i.e., from January 1893 are available. Tendencies of change in seasonal temperature-related climate extremes are demonstrated. "Cold" extremes have become less frequent and less severe than in the past, while "warm" extremes have become more frequent and more severe. Moreover, the interval of the occurrence of frost has been decreasing, while the interval of the occurrence of hot days has been increasing. However, many changes are not statistically significant, since the variability of temperature indices at the Potsdam station has been very strong.

  12. Lymphoscintigraphy of the lower extremity

    International Nuclear Information System (INIS)

    Abbasi, N.Z.

    1990-01-01

    Fifty one lower extremities of 26 normal healthy volunteers and 26 extremities of 13 patients with oedema have been studied. Dynamic quantitative lymphoscintigraphy using 99Tc-m antimony sulphide colloid during passive exercise as well as before and after active exercise was performed. parameters of lymphatic function including percentage of radioactivity cleared from the injection site, the percentage uptake by the inguinal lymph nodes, the time of arrival of activity at the regional lymph nodes and the lymphatic reserve index have been evaluated. The percentage clearance of activity from the injection site was found technically difficult to standardize and proved to be an unreliable parameter of lymphatic function. However, the quantitation of nodal uptake, the lymphatic transit time and the lymphatic reserve capacity accurately depicted the lymphatic functional status of an individual. The physiologic parameters of lymphatic function of the contralateral lower extremities were compared and a physiologic difference in the lymphatic capacity of the two limbs was scintigraphically documented. (author)

  13. Measuring risk of crude oil at extreme quantiles

    Directory of Open Access Journals (Sweden)

    Saša Žiković

    2011-06-01

    Full Text Available The purpose of this paper is to investigate the performance of VaR models at measuring risk for WTI oil one-month futures returns. Risk models, ranging from industry standards such as RiskMetrics and historical simulation to conditional extreme value model, are used to calculate commodity market risk at extreme quantiles: 0.95, 0.99, 0.995 and 0.999 for both long and short trading positions. Our results show that out of the tested fat tailed distributions, generalised Pareto distribution provides the best fit to both tails of oil returns although tails differ significantly, with the right tail having a higher tail index, indicative of more extreme events. The main conclusion is that, in the analysed period, only extreme value theory based models provide a reasonable degree of safety while widespread VaR models do not provide adequate risk coverage and their performance is especially weak for short position in oil.

  14. Statistical Model of Extreme Shear

    DEFF Research Database (Denmark)

    Hansen, Kurt Schaldemose; Larsen, Gunner Chr.

    2005-01-01

    In order to continue cost-optimisation of modern large wind turbines, it is important to continuously increase the knowledge of wind field parameters relevant to design loads. This paper presents a general statistical model that offers site-specific prediction of the probability density function...... by a model that, on a statistically consistent basis, describes the most likely spatial shape of an extreme wind shear event. Predictions from the model have been compared with results from an extreme value data analysis, based on a large number of full-scale measurements recorded with a high sampling rate...

  15. Automation Rover for Extreme Environments

    Science.gov (United States)

    Sauder, Jonathan; Hilgemann, Evan; Johnson, Michael; Parness, Aaron; Hall, Jeffrey; Kawata, Jessie; Stack, Kathryn

    2017-01-01

    Almost 2,300 years ago the ancient Greeks built the Antikythera automaton. This purely mechanical computer accurately predicted past and future astronomical events long before electronics existed1. Automata have been credibly used for hundreds of years as computers, art pieces, and clocks. However, in the past several decades automata have become less popular as the capabilities of electronics increased, leaving them an unexplored solution for robotic spacecraft. The Automaton Rover for Extreme Environments (AREE) proposes an exciting paradigm shift from electronics to a fully mechanical system, enabling longitudinal exploration of the most extreme environments within the solar system.

  16. Hygienic diagnosis in extreme conditions

    International Nuclear Information System (INIS)

    Sofronov, G.A.

    1997-01-01

    Review for book by M.P. Zakharchenko, S.A. Lopatin, G.N. Novozhilov, V.I. Zakharov Hygienic diagnosis in extreme conditions is presented discussing the problem of people health preservation under extreme conditions. Hygienic diagnosis is considered illustrated by cases of hostilities (Afghan War), earthquake response in Armenia (1988) and Chernobyl accident response. Attention is paid to the estimation of radiation doses to people and characteristics of main types of dosimeters. The high scientific level of the book is marked

  17. Extreme Conditions Modeling Workshop Report

    Energy Technology Data Exchange (ETDEWEB)

    Coe, R. G.; Neary, V. S.; Lawson, M. J.; Yu, Y.; Weber, J.

    2014-07-01

    Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) hosted the Wave Energy Converter (WEC) Extreme Conditions Modeling (ECM) Workshop in Albuquerque, NM on May 13th-14th, 2014. The objective of the workshop was to review the current state of knowledge on how to model WECs in extreme conditions (e.g. hurricanes and other large storms) and to suggest how U.S. Department of Energy (DOE) and national laboratory resources could be used to improve ECM methods for the benefit of the wave energy industry.

  18. Moving in extreme environments: what's extreme and who decides?

    Science.gov (United States)

    Cotter, James David; Tipton, Michael J

    2014-01-01

    Humans work, rest and play in immensely varied extreme environments. The term 'extreme' typically refers to insufficiency or excess of one or more stressors, such as thermal energy or gravity. Individuals' behavioural and physiological capacity to endure and enjoy such environments varies immensely. Adverse effects of acute exposure to these environments are readily identifiable (e.g. heat stroke or bone fracture), whereas adverse effects of chronic exposure (e.g. stress fractures or osteoporosis) may be as important but much less discernable. Modern societies have increasingly sought to protect people from such stressors and, in that way, minimise their adverse effects. Regulations are thus established, and advice is provided on what is 'acceptable' exposure. Examples include work/rest cycles in the heat, hydration regimes, rates of ascent to and duration of stay at altitude and diving depth. While usually valuable and well intentioned, it is important to realise the breadth and importance of limitations associated with such guidelines. Regulations and advisories leave less room for self-determination, learning and perhaps adaptation. Regulations based on stress (e.g. work/rest cycles relative to WBGT) are more practical but less direct than those based on strain (e.g. core temperature), but even the latter can be substantively limited (e.g. by lack of criterion validation and allowance for behavioural regulation in the research on which they are based). Extreme Physiology & Medicine is publishing a series of reviews aimed at critically examining the issues involved with self- versus regulation-controlled human movement acutely and chronically in extreme environments. These papers, arising from a research symposium in 2013, are about the impact of people engaging in such environments and the effect of rules and guidelines on their safety, enjoyment, autonomy and productivity. The reviews will cover occupational heat stress, sporting heat stress, hydration, diving

  19. Extreme conditions (p, T, H)

    Energy Technology Data Exchange (ETDEWEB)

    Mesot, J [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    The aim of this paper is to summarize the sample environment which will be accessible at the SINQ. In order to illustrate the type of experiments which will be feasible under extreme conditions of temperature, magnetic field and pressure at the SINQ a few selected examples are also given. (author) 7 figs., 14 refs.

  20. Book review: Extreme ocean waves

    Science.gov (United States)

    Geist, Eric L.

    2011-01-01

    ‘‘Extreme Ocean Waves’’ is a collection of ten papers edited by Efim Pelinovsky and Christian Kharif that followed the April 2007 meeting of the General Assembly of the European Geosciences Union. A note on terminology: extreme waves in this volume broadly encompass different types of waves, includ- ing deep-water and shallow-water rogue waves (alternatively termed freak waves), storm surges from cyclones, and internal waves. Other types of waves such as tsunamis or rissaga (meteotsunamis) are not discussed in this volume. It is generally implied that ‘‘extreme’’ has a statistical connotation relative to the average or significant wave height specific to each type of wave. Throughout the book, in fact, the reader will find a combination of theoretical and statistical/ empirical treatment necessary for the complete examination of this subject. In the introduction, the editors underscore the importance of studying extreme waves, documenting several dramatic instances of damaging extreme waves that occurred in 2007. 

  1. Extreme Energy Events Monitoring report

    CERN Document Server

    Baimukhamedova, Nigina

    2015-01-01

    Following paper reflects the progress I made on Summer Student Program within Extreme Energy Events Monitor project I was working on. During 8 week period I managed to build a simple detector system that is capable of triggering events similar to explosions (sudden change in sound levels) and measuring approximate location of the event. Source codes are available upon request and settings described further.

  2. Astrobiology: Life in Extreme Environments

    Science.gov (United States)

    Kaur, Preeti

    2011-01-01

    Astrobiology is the study of the origin, evolution and distribution of life in the universe. It seeks to answer two important scientific questions: how did we get here and are we alone in the universe? Scientists begin by studying life on Earth and its limits. The discovery of extremophiles on Earth capable of surviving extremes encourages the…

  3. Nutrition security under extreme events

    Science.gov (United States)

    Martinez, A.

    2017-12-01

    Nutrition security under extreme events. Zero hunger being one of the Sustainable Development Goal from the United Nations, food security has become a trending research topic. However extreme events impact on global food security is not yet 100% understood and there is a lack of comprehension of the underlying mechanisms of global food trade and nutrition security to improve countries resilience to extreme events. In a globalized world, food is still a highly regulated commodity and a strategic resource. A drought happening in a net food-exporter will have little to no effect on its own population but the repercussion on net food-importers can be extreme. In this project, we propose a methodology to describe and quantify the impact of a local drought to human health at a global scale. For this purpose, nutrition supply and global trade data from FAOSTAT have been used with domestic food production from national agencies and FAOSTAT, global precipitation from the Climate Research Unit and health data from the World Health Organization. A modified Herfindahl-Hirschman Index (HHI) has been developed to measure the level of resilience of one country to a drought happening in another country. This index describes how a country is dependent of importation and how diverse are its importation. Losses of production and exportation due to extreme events have been calculated using yield data and a simple food balance at country scale. Results show that countries the most affected by global droughts are the one with the highest dependency to one exporting country. Changes induced by droughts also disturbed their domestic proteins, fat and calories supply resulting most of the time in a higher intake of calories or fat over proteins.

  4. "Fate: The short film"

    OpenAIRE

    Maya Quintana, Jennifer

    2014-01-01

    "Fate: The Short Film" is a four minute short film which reflects the idea that nobody can escape from the fate. It has a good picture and sound quality with an understandable message for all public and with the collaboration of actors, filmmaker, stylist, script advisor and media technician.

  5. [Shunt and short circuit].

    Science.gov (United States)

    Rangel-Abundis, Alberto

    2006-01-01

    Shunt and short circuit are antonyms. In French, the term shunt has been adopted to denote the alternative pathway of blood flow. However, in French, as well as in Spanish, the word short circuit (court-circuit and cortocircuito) is synonymous with shunt, giving rise to a linguistic and scientific inconsistency. Scientific because shunt and short circuit made reference to a phenomenon that occurs in the field of the physics. Because shunt and short circuit are antonyms, it is necessary to clarify that shunt is an alternative pathway of flow from a net of high resistance to a net of low resistance, maintaining the stream. Short circuit is the interruption of the flow, because a high resistance impeaches the flood. This concept is applied to electrical and cardiovascular physiology, as well as to the metabolic pathways.

  6. Half-life of 214Po and 212Po measured with CTF at LNGS

    International Nuclear Information System (INIS)

    Bellini, G.; Benziger, J.; Bick, D.

    2013-01-01

    Polonium isotopes 214 Po and 212 Po are part of the 238 U and 232 Th decay chains, respectively. There exist only a few measurements of these two mean lifetimes with precision better than one or two percent. Since we have been studying decay spectra of 214 Bi and 212 Bi with the purpose of experimentally constraining anti-neutrino spectral shape important for geoneutrino studies, we have a large statistics of decays of 214 Po and 212 Po collected with the Counting Test Facility (CTF), which was operational in the underground I.N.F.N. Gran Sasso National Laboratory. The apparatus consisted of an external cylindrical water tank (diameter ∼ 11 m, high ∼ 10 m; ∼ 1000 tons of water) serving as passive shielding for 4.8 m 3 of liquid organic scintillator contained in an inner spherical vessel with a diameter of ∼ 2 m. The inner vessel was realized with a nylon membrane (∼ 500 ?m thick), with excellent optical clarity, which allowed the effective transmission of the scintillation light to the 100 phototubes (PMTs) forming the optical read-out, anchored on a 7 m diameter support structure inside the water tank. The high purity and low background in CTF allows a favourable signal to background ratio for these measurements. More specifically the ratio of signal to background of the present measurements is more than three orders of magnitude larger than the best existing measurements. We have studied the decays of 214 Po into 210 Pb and of 212 Po into 208 Pb tagged by the coincidence with the previously decays from 214 Bi and 212 Bi by using 222 Rn, 232 Th and 220 Rn sources sealed inside quartz vials and inserted in the CTF

  7. Intrinsically Disordered Segments Affect Protein Half-Life in the Cell and during Evolution

    NARCIS (Netherlands)

    Lee, R.T.J.G. van der; Lang, B.; Kruse, K.; Gsponer, J.; Groot, N.; Huynen, M.A.; Matouschek, A.; Fuxreiter, M.; Babu, M.M.

    2014-01-01

    Precise control of protein turnover is essential for cellular homeostasis. The ubiquitin-proteasome system is well established as a major regulator of protein degradation, but an understanding of how inherent structural features influence the lifetimes of proteins is lacking. We report that yeast,

  8. Analysis of a spectrum of a positron annihilation half life through inverse problem studies

    International Nuclear Information System (INIS)

    Monteiro, Roberto Pellacani G.; Viterbo, Vanessa C.; Braga, Joao Pedro; Magalhaes, Wellington F. de; Braga, A.P.

    2002-01-01

    Inversion of positron annihilation lifetime spectroscopy, based on a neural network Hopfield model and singular value decomposition (SVD) associated to Tikhonov regularization is presented in this work. From a previous reported density function for lysozyme in water a simulated spectrum, without spectrometer resolution effects, was generated. The precision of the inverted density function was analyzed taking into account the number of neurons and the learning time of the Hopfield network and the maximum position and areas for the spectral peaks in the SVD method considering noise and noiseless data. A fair agreement was obtained when comparing the inversion results with direct exact results. (author)

  9. Half-life calculation of one-proton emitters with a shell model potential

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, M. M.; Duarte, S. B. [Centro Brasileiro de Pesquisas Fisicas-CBPF/MCT Rua Dr. Xavier Sigaud, 150, 22290-180, Rio de Janeiro-RJ (Brazil); Teruya, N. [Departamento de Fisica, Universidade Federal da Paraiba - UFPB Campus de Joao Pessoa, 58051-970, Joao Pessoa - PB (Brazil)

    2013-03-25

    The accumulated amount of data for half-lives of proton emitters still remains a challenge to the ability of nuclear models to reproduce them consistently. These nuclei are far from beta stability line in a region where the validity of current nuclear models is not guaranteed. A nuclear shell model is introduced to the calculation of the nuclear barrier of less deformed proton emitters. The predictions using the proposed model are in good agreement with the data, with the advantage of have used only a single parameter in the model.

  10. Half-life measurements and photon emission probabilities of frequently applied radioisotopes

    International Nuclear Information System (INIS)

    Schoetzig, U.; Schrader, H.

    1998-09-01

    It belongs to the duties of the PTB department for 'Radioactivity' to determine the radioactivity emitted by radioactive radiation sources and publish their specific decay data, also called ''standards'', so that appliers of such sources may calibrate their equipment accordingly, as e.g. photon detectors. Further data required for proper calibration are those defining the photon emission probability per decay, P(E), at the relevant photon energy E. The emission rate R(E) is derived from the activity A, by the calculus R(E)=A x P(E), and the half-lives of decay, T 1 /2, together with the standards are used for determining the time of measurement. The calibration quality essentially is determined by those two parameters and the incertainties involved. The PTB 'Radioactivity' department therefore publishes for users recommended decay data elaborated and used by the experts at PTB. The tabulated data are either measured at PTB, or critically selected from data compilations of other publication sources. The tabulated decay data presented here are intended to serve as a source of reference for laboratory work and should be used in combination with the comprehensive data collections available (see the bibliography of this document: 86BRFI, 91TECD, 96FI, Nuclear Data Sheets, e.g. 98ND84). (orig./CB) [de

  11. Ecological half-life of radiocesium in reindeer after the Chernobyl accident

    International Nuclear Information System (INIS)

    Aahman, B.

    1992-01-01

    After the Chernobyl accident in April, 1986, a large part of the reindeer herding area of Sweden was contaminated with radioactive cesium. Radiocesium levels in four Saami communities have been studied from 1986-1992. Levels vary throughout the year with low values in summer and high in winter. Long-term half-lives were determined as being in most cases between the range of 2.5 - 4 years which is much shorter than that found after nuclear weapon tests (i.e. 7 years). (AB)

  12. Half Life: The Divided Life of Bruno Pontecorvo, Physicist or Spy

    International Nuclear Information System (INIS)

    Close, Frank

    2016-01-01

    It was at the height of the Cold War, in the summer of 1950, when Bruno Pontecorvo mysteriously vanished behind the Iron Curtain. Who was he, and what caused him to disappear? Was he simply a physicist, or also a spy and communist radical? A protege of Enrico Fermi, Pontecorvo was one of the most promising nuclear physicists in the world. He spent years hunting for the Higgs boson of his day - the neutrino - a nearly massless particle thought to be essential to the process of particle decay. His work on the Manhattan Project helped to usher in the nuclear age, and confirmed his reputation as a brilliant physicist. Why, then, would he disappear as he stood on the cusp of true greatness, perhaps even the Nobel Prize? In this book, physicist and historian Frank Close offers a heretofore untold history of Pontecorvo's life, based on unprecedented access to Pontecorvo's friends and family and the Russian scientists with whom he would later work. Close takes a microscope to Pontecorvo's life, combining a thorough biography of one of the most important scientists of the twentieth century with the drama of Cold War espionage. With all the elements of a Cold War thriller - classified atomic research, an infamous double agent, a possible kidnapping by Soviet operatives - this book is a history of nuclear physics at perhaps its most powerful: when it created the bomb

  13. Half-life. After the Chernobyl accident: How safe is our food?

    International Nuclear Information System (INIS)

    1986-01-01

    The papers and discussions aim at clarifying the question to what extent consumers are actually exposed to radionuclides and what damaging effects of low-level radiation will have to be reckoned with in the future. Special significance was attached to the issue of the relevance of 'transfer factors' for the transition from the environment to food and thus into the human body. Several experts tried to clarify the aspects of body uptake/intake of radionuclides, their residence time and removal, and to make risk assessments, who, however, did not always agree. Specific recommendations by experts from consumer and environmental associations concerning diet and attitudes were discussed in the conference. These recommendations constitute a major result of the conference. The consumer institute intends to communicate the results achieved to a larger circle of multipliers beyond the actual participants. (orig./DG) [de

  14. Β--decay and cosmic-ray half-life of 54Mn

    International Nuclear Information System (INIS)

    Kibedi, T.; Kerr, M.; Dracoulis, G.D.; Byrne, A.P.; Norman, E.B.

    1995-05-01

    A superconducting solenoid electron spectrometer operated in the lens mode was adapted to search for the β - -decay of 54 Mn. The Compton-electron and other instrumental backgrounds have been significantly reduced by special shielding of the absorber system. An improved procedure has been developed to select the events by momenta. A limit of 2.7 x 10 -5 has been established for the β - branch

  15. Ecological half-life of 137Cs in lichens in an alpine region.

    Science.gov (United States)

    Machart, Peter; Hofmann, Werner; Türk, Roman; Steger, Ferdinand

    2007-01-01

    About 17 years after the Chernobyl accident, lichen samples were collected in an alpine region in Austria (Bad Gastein), which was heavily contaminated by the Chernobyl fallout. Measured 137Cs activity concentrations in selected lichens (Cetraria islandica, Cetraria cucullata, and Cladonia arbuscula) ranged from 100 to 1100 Bq kg(-1) dry weight, depending on lichen species and sampling site. Ecological half-lives for 137Cs in different lichen samples, obtained by comparison with earlier measurements of the same lichen species at the same site, ranged from 2 to 6 years, with average values between 3 and 4 years. Comparison with earlier studies indicated that ecological half-lives hardly changed during the last 10 years, suggesting that ecological clearance mechanisms (e.g. washout or soil transfer) did not vary substantially at the selected sampling area.

  16. N-glycosylation increases the circulatory half-life of human growth hormone

    DEFF Research Database (Denmark)

    Flintegaard, Thomas V; Thygesen, Peter; Rahbek-Nielsen, Henrik

    2010-01-01

    Therapeutic use of recombinant GH typically involves daily sc injections. We examined the possibilities for prolonging the in vivo circulation of GH by introducing N-glycans. Human GH variants with a single potential N-glycosylation site (N-X-S/T) introduced by site-directed mutagenesis were expr...

  17. Ecological half-life of 137Cs in lichens in an alpine region

    International Nuclear Information System (INIS)

    Machart, Peter; Hofmann, Werner; Tuerk, Roman; Steger, Ferdinand

    2007-01-01

    About 17 years after the Chernobyl accident, lichen samples were collected in an alpine region in Austria (Bad Gastein), which was heavily contaminated by the Chernobyl fallout. Measured 137 Cs activity concentrations in selected lichens (Cetraria islandica, Cetraria cucullata, and Cladonia arbuscula) ranged from 100 to 1100 Bq kg -1 dry weight, depending on lichen species and sampling site. Ecological half-lives for 137 Cs in different lichen samples, obtained by comparison with earlier measurements of the same lichen species at the same site, ranged from 2 to 6 years, with average values between 3 and 4 years. Comparison with earlier studies indicated that ecological half-lives hardly changed during the last 10 years, suggesting that ecological clearance mechanisms (e.g. washout or soil transfer) did not vary substantially at the selected sampling area

  18. Doubling and half-life times for a combined fission-fusion system

    Energy Technology Data Exchange (ETDEWEB)

    Pantis, G

    1982-01-01

    The long term fuel dynamics for a fission symbiotic system is examined under the assumption of discontinuous loading and offloading conditions. It is found that the breeding capacities of the core and the blankets identify several distinct fuel cycles. By numerical test and a specific comparison it is shown that doubling times and half-lives can differ by as much as 10% from those predicted by conventional methods.

  19. Persistence and Effective Half-Life of Chemical Warfare Agent VX on Grass Foliage

    Science.gov (United States)

    2017-08-01

    the plant leaves, including leaf epicuticular waxes and cuticle (Sanyal et al., 2006; Simini et al., 2016). The extent of persistence, penetration...diameter pots had been lined with two pieces of absorbent paper , then filled with 170 g (77.1 g dry mass) of the potting mix. After 7d post...replicate VX-contaminated leaves and respective negative (no VX) control leaves were removed from plants at specified times for analytical determination of

  20. Identification of radionuclides in γ ray spectrum with half life fitting

    International Nuclear Information System (INIS)

    Sodaye, Suparna; Sudarshan, K.; Tomar, B.S.; Mukhopadhyay, P.K.

    2001-01-01

    The peak shape analysis software PHAST developed by Electronic Division, BARC has been tested for identification of the radio nuclides using the least square fitting of the time correlated peak areas of the γ lines. The half lives fitted by the software were found to be in agreement with the library data within 10%. Thus the software was able to unambiguously identify the radionuclides in the γ ray spectrum. (author)

  1. Idiopathic short stature

    Directory of Open Access Journals (Sweden)

    Vlaški Jovan

    2013-01-01

    Full Text Available Growth is a complex process and the basic characteristic of child- hood growth monitoring provides insight into the physiological and pathological events in the body. Statistically, the short stature means departure from the values of height for age and sex (in a particular environment, which is below -2 standard deviation score, or less than -2 standard deviation, i.e. below the third percentile. Advances in molecular genetics have contributed to the improvement of diagnostics in endocrinology. Analysis of patients’ genotypes should not be performed before taking a classical history, detailed clinical examination and appropriate tests. In patients with idiopathic short stature specific causes are excluded, such as growth hormone deficiency, Turner syndrome, short stature due to low birth weight, intrauterine growth retardation, small for gestational age, dysmorphology syndromes and chronic childhood diseases. The exclusion of abovementioned conditions leaves a large number of children with short stature whose etiology includes patients with genetic short stature or familial short stature and those who are low in relation to genetic potential, and who could also have some unrecognized endocrine defect. Idiopathic short stature represents a short stature of unknown cause of heterogeneous etiology, and is characterized by a normal response of growth hormone during stimulation tests (>10 ng/ml or 20 mJ/l, without other disorders, of normal body mass and length at birth. In idiopathic short stature standard deviation score rates <-2.25 (-2 to -3 or <1.2 percentile. These are also criteria for the initiation of growth hormone therapy. In children with short stature there is also the presence of psychological and social suffering. Goals of treatment with growth hormone involve achieving normal height and normal growth rate during childhood.

  2. High-energy, short-pulse, carbon-dioxide lasers

    International Nuclear Information System (INIS)

    Fenstermacher, C.A.

    1979-01-01

    Lasers for fusion application represent a special class of short-pulse generators; not only must they generate extremely short temporal pulses of high quality, but they must do this at ultra-high powers and satisfy other stringent requirements by this application. This paper presents the status of the research and development of carbon-dioxide laser systems at the Los Alamos Scientific Laboratory, vis-a-vis the fusion requirements

  3. Pediatric lower extremity mower injuries.

    Science.gov (United States)

    Hill, Sean M; Elwood, Eric T

    2011-09-01

    Lawn mower injuries in children represent an unfortunate common problem to the plastic reconstructive surgeon. There are approximately 68,000 per year reported in the United States. Compounding this problem is the fact that a standard treatment algorithm does not exist. This study follows a series of 7 pediatric patients treated for lower extremity mower injuries by a single plastic surgeon. The extent of soft tissue injury varied. All patients were treated with negative pressure wound therapy as a bridge to definitive closure. Of the 7 patients, 4 required skin grafts, 1 required primary closure, 1 underwent a lower extremity amputation secondary to wounds, and 1 was repaired using a cross-leg flap. Function limitations were minimal for all of our patients after reconstruction. Our basic treatment algorithm is presented with initial debridement followed by the simplest method possible for wound closure using negative pressure wound therapy, if necessary.

  4. Extreme Conditions Modeling Workshop Report

    Energy Technology Data Exchange (ETDEWEB)

    Coe, Ryan Geoffrey [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Neary, Vincent Sinclair [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Lawon, Michael J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Yu, Yi-Hsiang [National Renewable Energy Lab. (NREL), Golden, CO (United States); Weber, Jochem [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-07-01

    Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) hosted the Wave Energy Converter (WEC) Extreme Conditions Modeling (ECM) Workshop in Albuquerque, New Mexico on May 13–14, 2014. The objective of the workshop was to review the current state of knowledge on how to numerically and experimentally model WECs in extreme conditions (e.g. large ocean storms) and to suggest how national laboratory resources could be used to improve ECM methods for the benefit of the wave energy industry. More than 30 U.S. and European WEC experts from industry, academia, and national research institutes attended the workshop, which consisted of presentations from W EC developers, invited keynote presentations from subject matter experts, breakout sessions, and a final plenary session .

  5. Extreme project. Progress report 2006

    International Nuclear Information System (INIS)

    Eyrolle, F.; Masson, O.; Charmasson, S.

    2007-01-01

    The E.X.T.R.E.M.E. project introduced in 2005 to the S.E.S.U.R.E. / L.E.R.C.M. has for objectives to acquire data on the consequences of the extreme climatic meteorological episodes on the distribution of the artificial radioisotopes within the various compartments of the geosphere. This report presents the synthesis of the actions developed in 2006 in positioning and in co financing of the project by means of regional or national research programs (C.A.R.M.A., E.X.T.R.E.M.A., E.C.C.O.R.E.V.I.), of data acquisition, valuation and scientific collaboration. (N.C.)

  6. On causality of extreme events

    Directory of Open Access Journals (Sweden)

    Massimiliano Zanin

    2016-06-01

    Full Text Available Multiple metrics have been developed to detect causality relations between data describing the elements constituting complex systems, all of them considering their evolution through time. Here we propose a metric able to detect causality within static data sets, by analysing how extreme events in one element correspond to the appearance of extreme events in a second one. The metric is able to detect non-linear causalities; to analyse both cross-sectional and longitudinal data sets; and to discriminate between real causalities and correlations caused by confounding factors. We validate the metric through synthetic data, dynamical and chaotic systems, and data representing the human brain activity in a cognitive task. We further show how the proposed metric is able to outperform classical causality metrics, provided non-linear relationships are present and large enough data sets are available.

  7. Extreme Nonlinear Optics An Introduction

    CERN Document Server

    Wegener, Martin

    2005-01-01

    Following the birth of the laser in 1960, the field of "nonlinear optics" rapidly emerged. Today, laser intensities and pulse durations are readily available, for which the concepts and approximations of traditional nonlinear optics no longer apply. In this regime of "extreme nonlinear optics," a large variety of novel and unusual effects arise, for example frequency doubling in inversion symmetric materials or high-harmonic generation in gases, which can lead to attosecond electromagnetic pulses or pulse trains. Other examples of "extreme nonlinear optics" cover diverse areas such as solid-state physics, atomic physics, relativistic free electrons in a vacuum and even the vacuum itself. This book starts with an introduction to the field based primarily on extensions of two famous textbook examples, namely the Lorentz oscillator model and the Drude model. Here the level of sophistication should be accessible to any undergraduate physics student. Many graphical illustrations and examples are given. The followi...

  8. Promoting Exit from Violent Extremism

    DEFF Research Database (Denmark)

    Dalgaard-Nielsen, Anja

    2013-01-01

    A number of Western countries are currently adding exit programs targeting militant Islamists to their counterterrorism efforts. Drawing on research into voluntary exit from violent extremism, this article identifies themes and issues that seem to cause doubt, leading to exit. It then provides a ...... the influence attempt as subtle as possible, use narratives and self-affirmatory strategies to reduce resistance to persuasion, and consider the possibility to promote attitudinal change via behavioral change as an alternative to seek to influence beliefs directly....

  9. Racial Extremism in the Army

    Science.gov (United States)

    1998-04-01

    of Deference ...................................................................................................... 46 1. The Separation of Powers Doctrine...to the military. This deference has a two-fold basis. First, the separation of powers in the U.S. Constitution gives authority to the executive (and...Why should there be judicial deference to the Army’s policy on extremism? There are two principal reasons. First, the Constitution’s separation of powers doctrine

  10. Large Extremity Peripheral Nerve Repair

    Science.gov (United States)

    2016-12-01

    LM, de Crombrugghe B. Some recent advances in the chemistry and biology of trans- forming growth factor-beta. J Cell Biol 1987;105:1039e45. 12. Hao Y...SUPPLEMENTARY NOTES 14. ABSTRACT In current war trauma, 20-30% of all extremity injuries and >80% of penetrating injuries being associated with peripheral nerve...through both axonal advance and in revascularization of the graft following placement. We are confident that this technology may allow us to

  11. Critical care at extremes of temperature: effects on patients, staff and equipment.

    Science.gov (United States)

    Hindle, Elise M; Henning, J D

    2014-12-01

    Modern travel and military operations have led to a significant increase in the need to provide medical care in extreme climates. Presently, there are few data on what happens to the doctor, their drugs and equipment when exposed to these extremes. A review was undertaken to find out the effects of 'extreme heat or cold' on anaesthesia and critical care; in addition, subject matter experts were contacted directly. Both extreme heat and extreme cold can cause a marked physiological response in a critically ill patient and the doctor treating these patients may also suffer a decrement in both physical and mental functioning. Equipment can malfunction when exposed to extremes of temperature and should ideally be stored and operated in a climatically controlled environment. Many drugs have a narrow range of temperatures in which they remain useable though some have been shown to remain effective if exposed to extremes of temperature for a short period of time. All personnel embarking on an expedition to an extreme temperature zone should be of sufficient physical robustness and ideally should have a period of acclimatisation which may help mitigate against some of the physiological effects of exposure to extreme heat or extreme cold. Expedition planners should aim to provide climatic control for drugs and equipment and should have logistical plans for replenishment of drugs and medical evacuation of casualties. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  12. Injuries in an Extreme Conditioning Program.

    Science.gov (United States)

    Aune, Kyle T; Powers, Joseph M

    2016-10-19

    Extreme conditioning programs (ECPs) are fitness training regimens relying on aerobic, plyometric, and resistance training exercises, often with high levels of intensity for a short duration of time. These programs have grown rapidly in popularity in recent years, but science describing the safety profile of these programs is lacking. The rate of injury in the extreme conditioning program is greater than the injury rate of weightlifting and the majority of injuries occur to the shoulder and back. Cross-sectional study. Level 4. This is a retrospective survey of injuries reported by athletes participating in an ECP. An injury survey was sent to 1100 members of Iron Tribe Fitness, a gym franchise with 5 locations across Birmingham, Alabama, that employs exercises consistent with an ECP in this study. An injury was defined as a physical condition resulting from ECP participation that caused the athlete to either seek medical treatment, take time off from exercising, or make modifications to his or her technique to continue. A total of 247 athletes (22%) completed the survey. The majority (57%) of athletes were male (n = 139), and 94% of athletes were white (n = 227). The mean age of athletes was 38.9 years (±8.9 years). Athletes reported participation in the ECP for, on average, 3.6 hours per week (± 1.2 hours). Eighty-five athletes (34%) reported that they had sustained an injury while participating in the ECP. A total of 132 injuries were recorded, yielding an estimated incidence of 2.71 per 1000 hours. The shoulder or upper arm was the most commonly injured body site, accounting for 38 injuries (15% of athletes). Athletes with a previous shoulder injury were 8.1 times as likely to injure their shoulder in the ECP compared with athletes with healthy shoulders. The trunk, back, head, or neck (n = 29, 12%) and the leg or knee (n = 29, 12%) were the second most commonly injured sites. The injury incidence rate among athletes with study estimates the incidence of

  13. Technology improves upper extremity rehabilitation.

    Science.gov (United States)

    Kowalczewski, Jan; Prochazka, Arthur

    2011-01-01

    Stroke survivors with hemiparesis and spinal cord injury (SCI) survivors with tetraplegia find it difficult or impossible to perform many activities of daily life. There is growing evidence that intensive exercise therapy, especially when supplemented with functional electrical stimulation (FES), can improve upper extremity function, but delivering the treatment can be costly, particularly after recipients leave rehabilitation facilities. Recently, there has been a growing level of interest among researchers and healthcare policymakers to deliver upper extremity treatments to people in their homes using in-home teletherapy (IHT). The few studies that have been carried out so far have encountered a variety of logistical and technical problems, not least the difficulty of conducting properly controlled and blinded protocols that satisfy the requirements of high-level evidence-based research. In most cases, the equipment and communications technology were not designed for individuals with upper extremity disability. It is clear that exercise therapy combined with interventions such as FES, supervised over the Internet, will soon be adopted worldwide in one form or another. Therefore it is timely that researchers, clinicians, and healthcare planners interested in assessing IHT be aware of the pros and cons of the new technology and the factors involved in designing appropriate studies of it. It is crucial to understand the technical barriers, the role of telesupervisors, the motor improvements that participants can reasonably expect and the process of optimizing IHT-exercise therapy protocols to maximize the benefits of the emerging technology. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Typologies of extreme longevity myths.

    Science.gov (United States)

    Young, Robert D; Desjardins, Bertrand; McLaughlin, Kirsten; Poulain, Michel; Perls, Thomas T

    2010-01-01

    Purpose. Political, national, religious, and other motivations have led the media and even scientists to errantly accept extreme longevity claims prima facie. We describe various causes of false claims of extraordinary longevity. Design and Methods. American Social Security Death Index files for the period 1980-2009 were queried for individuals with birth and death dates yielding ages 110+ years of age. Frequency was compared to a list of age-validated supercentenarians maintained by the Gerontology Research Group who died during the same time period. Age claims of 110+ years and the age validation experiences of the authors facilitated a list of typologies of false age claims. Results. Invalid age claim rates increase with age from 65% at age 110-111 to 98% by age 115 to 100% for 120+ years. Eleven typologies of false claims were: Religious Authority Myth, Village Elder Myth, Fountain of Youth Myth (substance), Shangri-La Myth (geographic), Nationalist Pride, Spiritual Practice, Familial Longevity, Individual and/or Family Notoriety, Military Service, Administrative Entry Error, and Pension-Social Entitlement Fraud. Conclusions. Understanding various causes of false extreme age claims is important for placing current, past, and future extreme longevity claims in context and for providing a necessary level of skepticism.

  15. Moderate and extreme maternal obesity.

    LENUS (Irish Health Repository)

    Abdelmaboud, M O

    2012-05-01

    The aim of this study was to investigate the prevalence of moderate and extreme obesity among an Irish obstetric population over a 10-year period, and to evaluate the obstetric features of such pregnancies. Of 31,869 women delivered during the years 2000-2009, there were 306 women in the study group, including 173 in the moderate or Class 2 obese category (BMI 35-39.9) and 133 in the extreme or Class 3 obese category (BMI > or = 40).The prevalence of obese women with BMI > or = 35 was 9.6 per 1000 (0.96%), with an upward trend observed from 2.1 per 1000 in the year 2000, to 11.8 per 1000 in the year 2009 (P = 0.001). There was an increase in emergency caesarean section (EMCS) risk for primigravida versus multigravid women, within both obese categories (P < 0.001). However, there was no significant difference in EMCS rates observed between Class 2 and Class 3 obese women, when matched for parity. The prevalence of moderate and extreme obesity reported in this population is high, and appears to be increasing. The increased rates of abdominal delivery, and the levels of associated morbidity observed, have serious implications for such women embarking on pregnancy.

  16. Attribution of climate extreme events

    Science.gov (United States)

    Trenberth, Kevin E.; Fasullo, John T.; Shepherd, Theodore G.

    2015-08-01

    There is a tremendous desire to attribute causes to weather and climate events that is often challenging from a physical standpoint. Headlines attributing an event solely to either human-induced climate change or natural variability can be misleading when both are invariably in play. The conventional attribution framework struggles with dynamically driven extremes because of the small signal-to-noise ratios and often uncertain nature of the forced changes. Here, we suggest that a different framing is desirable, which asks why such extremes unfold the way they do. Specifically, we suggest that it is more useful to regard the extreme circulation regime or weather event as being largely unaffected by climate change, and question whether known changes in the climate system's thermodynamic state affected the impact of the particular event. Some examples briefly illustrated include 'snowmaggedon' in February 2010, superstorm Sandy in October 2012 and supertyphoon Haiyan in November 2013, and, in more detail, the Boulder floods of September 2013, all of which were influenced by high sea surface temperatures that had a discernible human component.

  17. Typologies of Extreme Longevity Myths

    Directory of Open Access Journals (Sweden)

    Robert D. Young

    2010-01-01

    Full Text Available Purpose. Political, national, religious, and other motivations have led the media and even scientists to errantly accept extreme longevity claims prima facie. We describe various causes of false claims of extraordinary longevity. Design and Methods. American Social Security Death Index files for the period 1980–2009 were queried for individuals with birth and death dates yielding ages 110+ years of age. Frequency was compared to a list of age-validated supercentenarians maintained by the Gerontology Research Group who died during the same time period. Age claims of 110+ years and the age validation experiences of the authors facilitated a list of typologies of false age claims. Results. Invalid age claim rates increase with age from 65% at age 110-111 to 98% by age 115 to 100% for 120+ years. Eleven typologies of false claims were: Religious Authority Myth, Village Elder Myth, Fountain of Youth Myth (substance, Shangri-La Myth (geographic, Nationalist Pride, Spiritual Practice, Familial Longevity, Individual and/or Family Notoriety, Military Service, Administrative Entry Error, and Pension-Social Entitlement Fraud. Conclusions. Understanding various causes of false extreme age claims is important for placing current, past, and future extreme longevity claims in context and for providing a necessary level of skepticism.

  18. Modelling of spatio-temporal precipitation relevant for urban hydrology with focus on scales, extremes and climate change

    DEFF Research Database (Denmark)

    Sørup, Hjalte Jomo Danielsen

    -correlation lengths for sub-daily extreme precipitation besides having too low intensities. Especially the wrong spatial correlation structure is disturbing from an urban hydrological point of view as short-term extremes will cover too much ground if derived directly from bias corrected regional climate model output...... of precipitation are compared and used to rank climate models with respect to performance metrics. The four different observational data sets themselves are compared at daily temporal scale with respect to climate indices for mean and extreme precipitation. Data density seems to be a crucial parameter for good...... happening in summer and most of the daily extremes in fall. This behaviour is in good accordance with reality where short term extremes originate in convective precipitation cells that occur when it is very warm and longer term extremes originate in frontal systems that dominate the fall and winter seasons...

  19. Prospect for extreme field science

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, T. [Ludwig Maximilian Univ. and Max Planck Institute for Quantum Optics, Garching (Germany); Japan Atomic Energy Agency, Kyoto and KEK, Tsukuba (Japan)

    2009-11-15

    The kind of laser extreme light infrastructure (ELI) provides will usher in a class of experiments we have only dreamed of for years. The characteristics that ELI brings in include: the highest intensity ever, large fluence, and relatively high repetition rate. A personal view of the author on the prospect of harnessing this unprecedented opportunity for advancing science of extreme fields is presented. The first characteristic of ELI, its intensity, will allow us to access, as many have stressed already, extreme fields that hover around the Schwinger field or at the very least the neighboring fields in which vacuum begins to behave as a nonlinear medium. In this sense, we are seriously probing the 'material' property of vacuum and thus the property that theory of relativity itself described and will entail. We will probe both special theory and general theory of relativity in regimes that have been never tested so far. We may see a glimpse into the reach of relativity or even its breakdown in some extreme regimes. We will learn Einstein and may even go beyond Einstein, if our journey is led. Laser-driven acceleration both by the laser field itself and by the wakefield that is triggered in a plasma is huge. Energies, if not luminosity, we can access, may be unprecedented going far beyond TeV. The nice thing about ELI is that it has relatively high repetition rate and average fluence as compared with other extreme lasers. This high fluence can be a key element that leads to applications to high energy physics, such as gamma-gamma collider driver experiment, and some gamma ray experiments that may be relevant in the frontier of photo-nuclear physics, and atomic energy applications. Needless to say, high fluence is one of most important features that industrial and medical applications may need. If we are lucky, we may see a door opens at the frontier of novel physics that may not be available by any other means. (authors)

  20. Imaging in short stature.

    Science.gov (United States)

    Chaudhary, Vikas; Bano, Shahina

    2012-09-01

    Short stature can be a sign of disease, disability, and social stigma causing psychological stress. It is important to have an early diagnosis and treatment. Short stature may result from skeletal dysplasias, endocrine disorders, may be familial, or may be the result of malnutrition and chronic illnesses. A team effort of the healthcare professionals like pediatricians, endocrinologists, radiologists, and pathologists is required to diagnose, treat and monitor various pathological conditions associated with growth abnormality. In this review, we have discussed the role of imaging in diagnosing and characterizing various pathological conditions associated with short stature.