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Sample records for 90nb 93mmo 96tc

  1. High Spin States in Vdd-odd Nucleus 90Nb

    Institute of Scientific and Technical Information of China (English)

    CUIXing-zhu; ZHULi-hua; WUXiao-guang; LIGuang-sheng; WENShu-xian; WANGZhi-min; HEChuang-ye; ZHANGZhen-long; MENGRui; MARui-gang; LUOPeng; ZHENGYong; M.M.Ndontchueng

    2003-01-01

    The high spin states of 90Nb were populated through the fusion-evaporation reaction 76Ge(19F,5n)90Nb. The 80 MeV 19F beams was delivered by the HI-13 tandem accelerator in China Institute of Atomic Energy. The 76Ge target is 2.2 mg/cm2 thick and evaporated on 10 mg/cm2 lead backing. The γ-rays from the reaction residues were recorded using 14 Compton suppressed HPGe-BGO spectrometersin γ-γ coincident mode.

  2. {sup 90}Nb - a potential PET nuclide. Production and labeling of monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Radchenko, V.; Roesch, F. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Hauser, H.; Eisenhut, M. [German Cancer Research Center, Heidelberg (Germany). Radiopharmaceutical Chemistry; Vugts, D.J.; Dongen, G.A.M.S. van [VU University Medical Center, Amsterdam (Netherlands). Dept. of Nuclear Medicine and PET Research; VU University Medical Center, Amsterdam (Netherlands). Dept. of Otolaryngology/Head and Neck Surgery

    2012-07-01

    Fast progressing immuno-PET gives reasons to develop new potential medium-long and long-lived radioisotopes. One of the promising candidates is {sup 90}Nb. It has a half-life of 14.6 h, which allows visualizing and quantifying processes with medium and slow kinetics, such as tumor accumulation of antibodies and antibodies fragments or polymers and other nanoparticles. {sup 90}Nb exhibits a high positron branching of 53% and an optimal energy of {beta}{sup +} emission of E{sub mean} = 0.35 MeV only. Consequently, efficient radionuclide production routes and Nb{sup V} labeling techniques are required. {sup 90}Nb was produced by the {sup 90}Zr(p,n){sup 90}Nb nuclear reaction on natural zirconium targets. No-carrier-added (n.c.a.) {sup 90}Nb was separated from the zirconium target via a multi-step separation procedure including extraction steps and ion-exchange chromatography. Protein labeling was exemplified using the bifunctional chelator desferrioxamine attached to the monoclonal antibody rituximab. Desferrioxamine was coupled to rituximab via two different routes, by the use of N-succinyl-desferrioxamine (N-suc-Df) and by means of the bifunctional derivative p-isothiocyanatobenzyl-desferrioxamine B (Df-Bz-NCS), respectively. Following antibody modification, labeling with {sup 90}Nb was performed in HEPES buffer at pH 7 at room temperature. In vitro stability of the radiolabeled conjugates was tested in saline buffer at room temperature and in fetal calf serum (FCS) at 37 C. The selected production route led to a high yield of 145 {+-} 10 MBq/{mu}A h of {sup 90}Nb with high radioisotopic purity of > 97%. This yield may allow for large scale production of about 10 GBq {sup 90}Nb. The separation procedure resulted in 76-81% yield. The Zr/{sup 90}Nb decontamination factor reaches 10{sup 7}. Subsequent radiolabeling of the two different conjugates with {sup 90}Nb gave high yields; after one hour incubation at room temperature, more than 90% of {sup 90}Nb-Df-mAb was

  3. 90Nb: potential radionuclide for application in immuno-PET. Development of appropriate production strategy and first in vivo evaluation of 90Nb-labeled monoclonal antibody

    International Nuclear Information System (INIS)

    Nuclear medicine is a modern and highly effective tool for the detection and treatment of oncological disease. Molecular imaging based on radiotracers includes single photon emission tomography (SPECT) and positron emission tomography (PET), which provide non-invasive tumor visualization on nano- and picomolar level, respectively. Currently, many novel tracers for more precise discovery of small tumors and metastases have been introduced and are under investigation. Many of them are protein-based biomolecules which nature herself produces as antigens for the eradication of tumor cells. Antibodies and antibody fragments play an important role in tumor diagnostics and treatment. PET imaging with antibodies and antibody fragments is called immuno-PET. The main issue that needs to be addressed is that appropriate radiotracers with half-lives related to the half-lives of biomolecules are needed. The development of novel radiotracers is a multistep, complicated task. This task includes the evaluation of production, separation and labeling strategy for chosen radionuclide. Finally, the biomolecule-radionuclide complex should be stable in time. An equally important factor is the economic suitability of the production strategy, which will lead to a key decision for future application of the developed radionuclide. In recent work, 90Nb has been proposed as a potential candidate for application in immuno-PET. Its half-life of 14.6 hours is suitable for application with antibody fragments and some intact antibodies. 90Nb has a relatively high positron branching of 53% and an optimal energy of β+ emission of 0.35 MeV that can provide high quality of imaging with low dose of used radionuclide. First proof-of-principle studies have shown that 90Nb: (i) can be produced in sufficient amount and purity by proton bombardment of natural zirconium target (ii) can be isolated from target material with appropriate radiochemical purity (iii) may be used for labeling of monoclonal

  4. Separation of {sup 90}Nb from zirconium target for application in immuno-PET

    Energy Technology Data Exchange (ETDEWEB)

    Radchenko, V.; Roesch, F. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Filosofov, D.V.; Bochko, O.K.; Lebedev, N.A.; Rakhimov, A.V. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Hauser, H.; Eisenhut, M. [German Cancer Research Center, Heidelberg (Germany). Radiopharmaceutical Chemistry; Aksenov, N.V.; Bozhikov, G.A. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation). Flerov Laboratory of Nuclear Reactions; Ponsard, B. [Belgian Nuclear Research Centre (SCKCEN), Mol (Belgium). Radioisotopes and NTD Silicon Production

    2014-07-01

    Fast progressing immuno-PET asks to explore new radionuclides. One of the promising candidates is {sup 90}Nb. It has a half-life of 14.6 h that allows visualizing and quantifying biological processes with medium and slow kinetics, such as tumor accumulation of antibodies and antibodies fragments or drug delivery systems and nanoparticles. {sup 90}Nb exhibits a positron branching of 53% and an average kinetic energy of emitted positrons of E{sub mean} = 0.35 MeV. Currently, radionuclide production routes and NbV labeling techniques are explored to turn this radionuclide into a useful imaging probe. However, efficient separation of {sup 90}Nb from irradiated targets remains in challenge. Ion exchange based separation of {sup 90}Nb from zirconium targets was investigated in systems AG 1 x 8 - HCl/H{sub 2}O{sub 2} and UTEVA-HCl. {sup 95}Nb (t{sub 1/2} = 35.0 d), {sup 95}Zr (t{sub 1/2} = 64.0 d) and {sup 92m}Nb (t{sub 1/2} = 10.15 d) were chosen for studies on distribution coefficients. Separation after AG 1 x 8 anion exchange yields 99% of {sup 90/95}Nb. Subsequent use of a solid-phase extraction step on UTEVA resin further decontaminates {sup 90/95}Nb from traces of zirconium with yields 95% of {sup 90/95}Nb. A semi-automated separation takes one hour to obtain an overall recovery of {sup 90/95}Nb of 90%. The amount of Zr was reduced by factor of 10{sup 8}. The selected separation provides rapid preparation (< 1 h) of high purity {sup 90}Nb appropriate for the synthesis of {sup 90}Nb-radiopharmaceuticals, relevant for purposes of immuno-PET. Applying the radioniobium obtained, {sup 90/95}Nb-labeling of a monoclonal antibody (rituximab) modified with desferrioxamine achieved labeling yields of > 90% after 1 h incubation at room temperature. (orig.)

  5. Nuclear data for the cyclotron production of 117Sb and 90Nb

    International Nuclear Information System (INIS)

    This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets, theoretical calculation of production yield, calculation of required thickness of target and suggestion of optimum reaction to produce Antimony-117 and Niobium-90. (authors)

  6. {sup 90}Nb: potential radionuclide for application in immuno-PET. Development of appropriate production strategy and first in vivo evaluation of {sup 90}Nb-labeled monoclonal antibody

    Energy Technology Data Exchange (ETDEWEB)

    Radchenko, Valery

    2013-07-01

    Nuclear medicine is a modern and highly effective tool for the detection and treatment of oncological disease. Molecular imaging based on radiotracers includes single photon emission tomography (SPECT) and positron emission tomography (PET), which provide non-invasive tumor visualization on nano- and picomolar level, respectively. Currently, many novel tracers for more precise discovery of small tumors and metastases have been introduced and are under investigation. Many of them are protein-based biomolecules which nature herself produces as antigens for the eradication of tumor cells. Antibodies and antibody fragments play an important role in tumor diagnostics and treatment. PET imaging with antibodies and antibody fragments is called immuno-PET. The main issue that needs to be addressed is that appropriate radiotracers with half-lives related to the half-lives of biomolecules are needed. The development of novel radiotracers is a multistep, complicated task. This task includes the evaluation of production, separation and labeling strategy for chosen radionuclide. Finally, the biomolecule-radionuclide complex should be stable in time. An equally important factor is the economic suitability of the production strategy, which will lead to a key decision for future application of the developed radionuclide. In recent work, {sup 90}Nb has been proposed as a potential candidate for application in immuno-PET. Its half-life of 14.6 hours is suitable for application with antibody fragments and some intact antibodies. {sup 90}Nb has a relatively high positron branching of 53% and an optimal energy of β{sup +} emission of 0.35 MeV that can provide high quality of imaging with low dose of used radionuclide. First proof-of-principle studies have shown that {sup 90}Nb: (i) can be produced in sufficient amount and purity by proton bombardment of natural zirconium target (ii) can be isolated from target material with appropriate radiochemical purity (iii) may be used for

  7. Desferrioxamine as an appropriate chelator for 90Nb: comparison of its complexation properties for M-Df-Octreotide (M = Nb, Fe, Ga, Zr).

    Science.gov (United States)

    Radchenko, Valery; Busse, Stefan; Roesch, Frank

    2014-10-01

    The niobium-90 radioisotope ((90)Nb) holds considerable promise for use in immuno-PET, due to its decay parameters (t½ = 14.6h, positron yield=53%, Eß(+)(mean) = 0.35 MeV and Eß(+)(max) = 1.5 MeV). In particular, (90)Nb appears well suited to detect in vivo the pharmacokinetics of large targeting vectors (50-150 kDa). In order to be useful for immuno-PET chelators are required to both stabilize the radionuclide in terms of coordination chemistry and to facilitate the covalent attachment to the targeting vector. Different chelators were evaluated for this purpose in terms of radiolabelling efficiency and stability of the radiolabelled Nb(V) complex and in order to determine the most suitable candidate for conjugation to a biologically relevant targeting vector. For the purpose of studying the complexation properties the niobium radioisotope (95)Nb was used as an analogue of (90)Nb, by virtue of its longer half-life (35 days) and lower cost (reactor-based production). Acyclic and cyclic chelators were investigated, with desferroxamine [Df: (N'-{5-[acetyl(hydroxy)amino]pentyl}-N-[5-({4-[(5-aminopentyl) (hydroxy)amino]-4-oxobutanoyl} amino)pentyl]-N-hydroxysuccinamide)] emerging as the best candidate. Greater than 99% radiolabelling was achieved at room temperature over a wide pH range. The (95)Nb-Df complex is sufficiently stable for immuno-PET (kinetics of the unconjugated chelator (Df) were retained for Df-succinyl-(D)Phe(1)-octreotide (Df-OC), with>90% labelling after 1h at room temperature over the pH range 5-7. Stability studies, performed in vitro in serum at physiological temperature (37 °C), revealed that 87 ± 2% of the radiolabelled molecule remained intact after 7 days. Competition studies with relevant metal ions (zirconium((IV)), gallium((III)) and iron((III))) have been performed with Df-OC to gain insight to the relative stability [Nb-Df]-OC complex to transmetallation. At equimolar metal ion concentrations the [Nb-Df]-OC complex showed the greatest

  8. Equilibrium and pre-equilibrium calculations of cross-sections of (, ) reactions on 89Y, 90Zr and 94Mo targets used for the production of 89Zr, 90Nb and 94Tc positron-emitting radionuclides

    Indian Academy of Sciences (India)

    R Baldik; H Aytekin; E Tel

    2013-02-01

    In this study, the pre-equilibrium and equilibrium calculations of cross-sections of 89Y(, ), 90Zr$(p, xn)$ and 94Mo(, ) reactions, which were used for the production of 89Zr, 90Nb and 94Tc positron-emitting radioisotopes, have been investigated. Pre-equilibrium calculations have been performed at different proton incident energies by using the hybrid, geometry-dependent-hybrid and full exciton models. The Weisskopf–Ewing model is used for calculating the equilibrium effects at the same incident energies. The calculated results have been discussed and compared with the experimental results.

  9. New activation cross section data on longer lived radio-nuclei produced in proton induced nuclear reaction on zirconium

    International Nuclear Information System (INIS)

    The excitation functions of 96Nb, 95mNb, 95gNb, 92mNb, 91mNb, 90Nb, 95Zr, 89Zr, 88Zr, 86Zr, 88Y, 87mY, 87gY, 86Y were measured up to 70 MeV proton energy by using the stacked foil technique and the activation method. The new data were compared with the critically analyzed experimental data in the literature and with the TALYS based model results in TENDL-2013 library. The possible role of the investigated reactions in the production of medically relevant 90Nb, 95mNb, 89Zr, and 88Y radionuclides is discussed. - Highlights: • Proton induced reactions on natural zirconium up to 65 MeV. • Stacked foil irradiation technique coupled with gamma-spectrometry. • Comparison of experimental data with the nuclear reaction model results in the TENDL-2013 library. • Calculation and comparison of thick target integral yields. • Comparison of the production routes of 90Nb, 95mNb, 89Zr and 88Y medically relevant radioisotopes

  10. Labeling and preliminary in vivo assessment of niobium-labeled radioactive species: A proof-of-concept study.

    Science.gov (United States)

    Radchenko, Valery; Bouziotis, Penelope; Tsotakos, Theodoros; Paravatou-Petsotas, Mari; la Fuente, Ana de; Loudos, George; Harris, Adrian L; Xanthopoulos, Stavros; Filosofov, Dmitry; Hauser, Harald; Eisenhut, Michael; Ponsard, Bernard; Roesch, Frank

    2016-05-01

    The application of radionuclide-labeled biomolecules such as monoclonal antibodies or antibody fragments for imaging purposes is called immunoscintigraphy. More specifically, when the nuclides used are positron emitters, such as zirconium-89, the technique is referred to as immuno-PET. Currently, there is an urgent need for radionuclides with a half-life which correlates well with the biological kinetics of the biomolecules under question and which can be attached to the proteins by robust labeling chemistry. (90)Nb is a promising candidate for in vivo immuno-PET, due its half-life of 14.6h and low β(+) energy of Emean=0.35MeV per decay. (95)Nb on the other hand, is a convenient alternative for longer-term ex vivo biodistribution studies, due to its longer half-life of (t½=35days) and its convenient, lower-cost production (reactor-based production). In this proof-of-principle work, the monoclonal antibody bevacizumab (Avastin(®)) was labeled with (95/90)Nb and in vitro and in vivo stability was evaluated in normal Swiss mice and in tumor-bearing SCID mice. Initial ex vivo experiments with (95)Nb-bevacizumab showed adequate tumor uptake, however at the same time high uptake in the liver, spleen and kidneys was observed. In order to investigate whether this behavior is due to instability of (⁎)Nb-bevacizumab or to the creation of other (⁎)Nb species in vivo, we performed biodistribution studies of (95)Nb-oxalate, (95)Nb-chloride and (95)Nb-Df. These potential metabolite species did not show any specific uptake, apart from bone accumulation for (95)Nb-oxalate and (95)Nb-chloride, which, interestingly, may serve as an "indicator" for the release of (90)Nb from labeled biomolecules. Concerning the initial uptake of (95)Nb-bevacizumab in non-tumor tissue, biodistribution of a higher specific activity radiolabeled antibody sample did show only negligible uptake in the liver, spleen, kidneys or bones. In-vivo imaging of a tumor-bearing SCID mouse after injection

  11. Labeling and preliminary in vivo assessment of niobium-labeled radioactive species: A proof-of-concept study.

    Science.gov (United States)

    Radchenko, Valery; Bouziotis, Penelope; Tsotakos, Theodoros; Paravatou-Petsotas, Mari; la Fuente, Ana de; Loudos, George; Harris, Adrian L; Xanthopoulos, Stavros; Filosofov, Dmitry; Hauser, Harald; Eisenhut, Michael; Ponsard, Bernard; Roesch, Frank

    2016-05-01

    The application of radionuclide-labeled biomolecules such as monoclonal antibodies or antibody fragments for imaging purposes is called immunoscintigraphy. More specifically, when the nuclides used are positron emitters, such as zirconium-89, the technique is referred to as immuno-PET. Currently, there is an urgent need for radionuclides with a half-life which correlates well with the biological kinetics of the biomolecules under question and which can be attached to the proteins by robust labeling chemistry. (90)Nb is a promising candidate for in vivo immuno-PET, due its half-life of 14.6h and low β(+) energy of Emean=0.35MeV per decay. (95)Nb on the other hand, is a convenient alternative for longer-term ex vivo biodistribution studies, due to its longer half-life of (t½=35days) and its convenient, lower-cost production (reactor-based production). In this proof-of-principle work, the monoclonal antibody bevacizumab (Avastin(®)) was labeled with (95/90)Nb and in vitro and in vivo stability was evaluated in normal Swiss mice and in tumor-bearing SCID mice. Initial ex vivo experiments with (95)Nb-bevacizumab showed adequate tumor uptake, however at the same time high uptake in the liver, spleen and kidneys was observed. In order to investigate whether this behavior is due to instability of (⁎)Nb-bevacizumab or to the creation of other (⁎)Nb species in vivo, we performed biodistribution studies of (95)Nb-oxalate, (95)Nb-chloride and (95)Nb-Df. These potential metabolite species did not show any specific uptake, apart from bone accumulation for (95)Nb-oxalate and (95)Nb-chloride, which, interestingly, may serve as an "indicator" for the release of (90)Nb from labeled biomolecules. Concerning the initial uptake of (95)Nb-bevacizumab in non-tumor tissue, biodistribution of a higher specific activity radiolabeled antibody sample did show only negligible uptake in the liver, spleen, kidneys or bones. In-vivo imaging of a tumor-bearing SCID mouse after injection

  12. Possible enhancement of magnetic dipole transition strength between Gamow-Teller and isobaric analog states

    International Nuclear Information System (INIS)

    The non-energy weighted sum rule of M1 transitions between IAS and GT states is found to be significantly enhanced compared to the sum rule of parent nucleus. Mechanism of this enhancement is explained. Transition strengths between specific states in 48Sc, 90Nb and 208Bi are calculated to investigate whether the enhancement of the sum rule is reflected in these transitions. Measurement of M1 transitions between IAS and GT states is recommended to obtain more information on the spin-isospin response in medium and heavy nuclei. (orig.)

  13. Measurement of activation products generated in the [18F]FDG production by a 9.6 MeV cyclotron

    Science.gov (United States)

    Chaves, J. Carbajo; Vargas, M. Jurado; Sánchez, R. Sánchez

    2016-09-01

    Gamma-ray spectrometry was used for the identification and quantification of the activation products induced during the production of [18F]FDG in a cyclotron with a beam of 9.6 MeV protons, a silver target and Havar entrance window. Samples of the irradiated water collected before and after the 18F separation, and of the final product [18F]FDG were measured in the particular conditions of a beam current of 45 μA and an irradiation time of 25-30 min The radionuclides 52Mn, 55Co, 56Co, 57Co, 58Co, 95Tc, 96Tc, and 109Cd were identified in the irradiated water samples, but not detected in the final [18]FDG product. The requirements for the transport of the recovered enriched water are also discussed.

  14. Country programme review Bangladesh

    International Nuclear Information System (INIS)

    A five-expert mission was organized from 21-26 August 1993 and this document reflects the findings and recommendations of the team. Intensive contacts with heads of institutions, scientists and decision making persons in various sectors in the country were co-ordinated by the Bangladesh Atomic Energy Commission. The terms of reference of the mission were: To assess the on-going TC projects; to assist the Bangladesh nationals to finalize the formulation of the new requests for 1995-96 TC programme and to establish priority areas with regard to the introduction of national projects involving accelerated technological transfer in order to catalyze national development plans in specific areas; to examine institutional framework suitable for the introduction of these priority nuclear techniques

  15. Stress corrosion cracking behavior in gaseous oxygen of a U-7.5 Nb-2.5 Zr alloy

    International Nuclear Information System (INIS)

    Stress corrosion of the alloy U90Nb7.5Zr2.5 in oxygen is studied for temperature between -200C and 1000C under pressure varying from 0.3 x 10-6 MPa to 0.15 MPa. The domain of stress corrosion and cracking kinetics are determined in function of stress intensity, temperature and pressure. Under 0.15 MPa of oxygen embrittlement is observed for the all range of temperature studied and the phenomenon is thermally activated. At room temperature cracks are produced for all tested pressures, influence of pressure on cracking kinetics is low. Auger spectrometry analysis on the surface of cracks shows a surface mechanism to explain alloy embrittlement in gaseous oxygen

  16. Phenomenological model of the clavulanic acid production process utilizing Streptomyces clavuligerus

    Directory of Open Access Journals (Sweden)

    A. Baptista-Neto

    2000-12-01

    Full Text Available The kinetics of clavulanic acid production process by Streptomyces clavuligerus NRRL 3585 was studied. Experiments were carried out in a 4 liters bioreactor, utilizing 2 complex media containing glycerol as the carbon and energy source, and peptone or Samprosoy 90NB (soybean protein as nitrogen source. Temperature was kept at 28°C and the dissolved oxygen was controlled automatically at 40 % saturation value. Samples were withdrawn for determination of cell mass (only peptone medium, glycerol and product concentrations. Gas analyzers allowed on line determination of CO2 and O2 contents in the exit gas. With Samprosoy, cell mass was evaluated by determining glycerol consumption and considering the cell yield, Y X/S, as being the same for both cases. Oxygen uptake and CO2 production rates were strongly related to growth and substrate consumption, allowing determination of stoichiometric constants in relation to growth, substrate, oxygen, product and carbon dioxide.

  17. Studies on stabilities of some human chorionic gonadotropin complexes with {beta}-emitting radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Maiti, Moumita [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Sen, Kamalika [Department of Chemistry, University of Calcutta, 92 APC Road, Kolkata 700009 (India); Sen, Souvik [Malda Town Divisional Railway Hospital, Malda 732102 (India); Lahiri, Susanta, E-mail: susanta.lahiri@saha.ac.i [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)

    2011-02-15

    Human chorionic gonadotropin (hCG) is a peptide hormone, whose one of the structural subunits is identical to that of thyroid-stimulating hormone (TSH). As a consequence, the receptors of TSH also act as receptor for hCG hormone. Keeping in mind this interesting property of hCG we have studied the complex formation ability of various no-carrier-added {beta}-emitting isotopes of {sup 61}Cu (3.3 h), {sup 62}Zn (9.2 h), {sup 90}Nb (14.60 h) and {sup 99}Mo (66.02 h) with hCG molecule. Stability of the hCG-M (M=metal ions) complexes was investigated by dialysis with respect to triple distilled water and ringer lactate solution, which has the same composition as extracellular fluid.

  18. Conversion probabilities of low-energy (ℎω≤3 keV) nuclear transitions in the electron shells of free atoms. Article translated from Journal Yadernye Konstanty (Nuclear Constants). Series: Nuclear Constants, Issue No. 1, 1987

    International Nuclear Information System (INIS)

    Conversion of some low-energy transitions (ℎω≤3 keV) in the nuclei 90Nb, 99Tc, 103Ru, 110Ag, 140Pr, 142Pr, 153Gd, 159Gd, 160Tb, 165Tm, 171Lu, 173W, 188Re, 193Pt, 201Hg, 205Pb, 236Pa and 250Bk are investigated for the case of an isolated atom. The conversion transition probabilities are calculated using the electron wave functions, obtained through numerical integration of the Dirac equations in the atomic field within the framework of the Hartree-Fock-Slater method. The calculation is carried out for the normal configuration of the valence band of the aforementioned atoms. The calculation results are tabulated in this paper. (author)

  19. Excitation function and isomeric ratio of Tc-isotopes from the {sup 93}Nb(α, xn) reaction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, G.N., E-mail: gnkim@knu.ac.kr [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Naik, H. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Rediochemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India); Zaman, M. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Yang, S.-C.; Song, T.-Y. [Nuclear Data Center, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Guin, R.; Das, S.K. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064 (India)

    2015-03-15

    The excitation functions of {sup 94–96}Tc isotopes and independent isomeric ratios of {sup 93m, g}Tc, {sup 94m, g}Tc, and {sup 95m, g}Tc from the {sup 93}Nb(α, xn) reaction within the energy range below 40 MeV have been determined by using a stacked-foil activation and an off-line γ-ray spectrometric technique at the Variable Energy Cyclotron Center, Kolkota, India. The excitation function of {sup 94–96}Tc in the {sup 93}Nb(α, xn) reaction was also calculated by using the computer code TALYS 1.6. The present data are found to be in general agreement with the literature data but have similar trend with some deviation from calculated data of the TALYS 1.6 code. The isomeric ratios of {sup 93m, g}Tc, {sup 94m, g}Tc, and {sup 95m, g}Tc in the {sup 93}Nb(α, xn) reactions from the present work and literature data were compared with similar data in the {sup 93}Nb({sup 3}He, xn) and {sup 96}Mo(p, xn) reactions. In all the three reactions, the isomeric ratios increase with the increasing excitation energy. However, at all excitation energies, the isomeric ratios of {sup 93m, g}Tc, {sup 94m, g}Tc, and {sup 95m, g}Tc in the {sup 93}Nb(α, xn) and {sup 93}Nb({sup 3}He, xn) reactions are higher than those in the {sup 96}Mo(p, xn) reactions, which indicate the role of input angular momentum besides excitation energy. Above the excitation energy of 35–55 MeV, the isomeric ratios of {sup 95m, g}Tc, {sup 94m, g}Tc, and {sup 93m, g}Tc decrease in all the {sup 93}Nb(α, xn), {sup 93}Nb({sup 3}He, xn) and {sup 96}Mo(p, xn) reactions. This decreasing trend at higher excitation energy indicates the starting of pre-equilibrium reaction, which depends on the target, projectile, and type of reaction products.

  20. Fetoplacental transport of various trace elements in pregnant rat using the multitracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Enomoto, Shuichi; Hirunuma, Rieko [Radioisotope Technology Division, Cyclotron Center, Institute of Physical and Chemical Research (RIKEN), Wako, Saitama (Japan)

    2001-05-01

    The placenta functions as the barrier between fetus and mother, providing means of regulation of heat exchange, respiration, nutrition, and excretion for the fetus. In this paper, the multitracer technique was applied to study the maternal transport of trace elements via the placenta to the fetus. In this experiment, the multitracer solution used contained the following nuclides: {sup 7}Be, {sup 22}Na, {sup 46}Sc, {sup 48}V, {sup 52}Mn, {sup 59}Fe, {sup 56}Co, {sup 65}Zn, {sup 67}Ga, {sup 74}As, {sup 75}Se, {sup 84}Rb, {sup 85}Sr, {sup 87}Y, {sup 88}Zr, {sup 96}Tc, {sup 101m}Rh, and {sup 103}Ru. We examined the time dependence of the uptake amounts about various elements. From these results, we observed a large difference in the time dependencies between elements and the elements were classified into three groups. Group I elements, such as Be, Sc, V, As, Y, Zr, Tc, Rh, and Ru, are transported to the placenta from the maternal blood and only accumulates in the placenta. Group II elements, such as Na, Co, Ga, Rb, and Sr, are transported to the placenta from the maternal blood and accumulate in the placenta, fetus, and amniotic fluid. Group III elements, such as Mn, Fe, Zn, and Se, are transported to the placenta from the maternal blood and mainly accumulate in the fetus. From these results, it was considered that the placenta is a highly selective filters because essential elements such as Group III elements are readily transported from the placental membrane to the growing fetus, whereas nonessential metals such as Group I elements have difficulty penetrating the placental barrier that protects the fetus from the toxic effects of these elements. (author)

  1. Antigenicity and diagnostic potential of vaccine candidates in human Chagas disease.

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    Shivali Gupta

    Full Text Available BACKGROUND: Chagas disease, caused by Trypanosoma cruzi, is endemic in Latin America and an emerging infectious disease in the US and Europe. We have shown TcG1, TcG2, and TcG4 antigens elicit protective immunity to T. cruzi in mice and dogs. Herein, we investigated antigenicity of the recombinant proteins in humans to determine their potential utility for the development of next generation diagnostics for screening of T. cruzi infection and Chagas disease. METHODS AND RESULTS: Sera samples from inhabitants of the endemic areas of Argentina-Bolivia and Mexico-Guatemala were analyzed in 1(st-phase for anti-T. cruzi antibody response by traditional serology tests; and in 2(nd-phase for antibody response to the recombinant antigens (individually or mixed by an ELISA. We noted similar antibody response to candidate antigens in sera samples from inhabitants of Argentina and Mexico (n=175. The IgG antibodies to TcG1, TcG2, and TcG4 (individually and TcG(mix were present in 62-71%, 65-78% and 72-82%, and 89-93% of the subjects, respectively, identified to be seropositive by traditional serology. Recombinant TcG1- (93.6%, TcG2- (96%, TcG4- (94.6% and TcG(mix- (98% based ELISA exhibited significantly higher specificity compared to that noted for T. cruzi trypomastigote-based ELISA (77.8% in diagnosing T. cruzi-infection and avoiding cross-reactivity to Leishmania spp. No significant correlation was noted in the sera levels of antibody response and clinical severity of Chagas disease in seropositive subjects. CONCLUSIONS: Three candidate antigens were recognized by antibody response in chagasic patients from two distinct study sites and expressed in diverse strains of the circulating parasites. A multiplex ELISA detecting antibody response to three antigens was highly sensitive and specific in diagnosing T. cruzi infection in humans, suggesting that a diagnostic kit based on TcG1, TcG2 and TcG4 recombinant proteins will be useful in diverse situations.